BRST quantization, IOSp(D,2vertical stroke2) invariance and the PCT theorem. Pt. 2

International Nuclear Information System (INIS)

Gozzi, E.; Reuter, M.

1989-01-01

In this paper we investigate the IOSp(D,2vertical stroke2) extension of the Poincare group in the BRST quantization of the spinning particle. We construct the corresponding field theory and prove its dimensional reduction a la Parisi-Sourlas. As for the scalar particle, we show that the PCT transformation is induced by a certain element of the SO(D,2) subgroup of the IOSp(D,2vertical stroke2). This gives us the tools for a simple interpretation of the PCT theorem for Dirac fields. We then continue by clarifying the role of the 'modular' transformation (i.e. world-line orientation-reversing diffeomorphism) and indicating how the PCT transformation could be regarded as a modular transformation in a 'SO(D,2)-rotated' frame. In this work we also consider BRST field theories leading to D-dimensional chiral theories. In this case, of the full IOSp(D,2vertical stroke2) symmetry, only the subgroup IO(D-1,1)xOSp(1,1vertical stroke2) survives together with the (isolated) SO(D,2) transformation that implements PCT. (orig.)

The Work Softening by Deformation-Induced Disordering and Cold Rolling of 6.5 wt pct Si Steel Thin Sheets

Science.gov (United States)

Wang, Xianglong; Li, Haoze; Zhang, Weina; Liu, Zhenyu; Wang, Guodong; Luo, Zhonghan; Zhang, Fengquan

2016-09-01

As-cast strip of 6.5 wt pct Si steel was fabricated by twin-roll strip casting. After hot rolling at 1323 K (1050 °C), thin sheets with the thickness of 0.35 mm were produced by warm rolling at 373 K (100 °C) with rolling reductions of 15, 25, 35, 45, 55, and 65 pct. Influence of warm rolling reduction on ductility was investigated by room temperature bending test. The measurement of macro-hardness showed that "work softening" could begin when the warm rolling reduction exceeded 35 pct. The room temperature ductility of the thin sheets gradually increased with the increase of warm rolling reductions, and the plastic deformation during bending began to form when the warm rolling reduction was greater than 45 pct, the 65 pct rolled thin sheet exhibited the maximum plastic deformation of about 0.6 pct during bending at room temperature, with a few small dimples having been observed on the fracture surfaces. B2-ordered domains were formed in the 15, 25, 35, 45, and 55 pct rolled specimens, and their average size decreased with the increase of warm rolling reductions. By contrast, no B2-ordered domain could be found in the 65 pct rolled specimen. It had been observed that large-ordered domains could be split into several small parts by the slip of partial super-dislocations during warm rolling, which led to significant decrease of the order degree to cause the phenomenon of deformation-induced disordering. On the basis of these results, cold rolling schedule was developed to successfully fabricate 0.25-mm-thick sheets with good surface qualities and magnetic properties from warm rolled sheets.

Hot Ductility Behavior of an 8 Pct Cr Roller Steel

Science.gov (United States)

Wang, Zhenhua; Sun, Shuhua; Shi, Zhongping; Wang, Bo; Fu, Wantang

2015-04-01

The hot ductility of an 8 pct Cr roller steel was determined between 1173 K and 1473 K (900 °C and 1200 °C) at strain rates of 0.01 to 10 s-1 through tensile testing. The fracture morphology was observed using scanning electron microscopy, and the microstructure was examined through optical microscopy and transmission electron microscopy. The dependence of the hot ductility behavior on the deformation conditions, grain size, and precipitation was analyzed. The relationship between the reduction in area and the natural logarithm of the Zener-Hollomon parameter (ln Z) was found to be a second-order polynomial. When ln Z was greater than 40 s-1, the hot ductility was poor and fracture was mainly caused by incompatible deformation between the grains. When ln Z was between 32 and 40 s-1, the hot ductility was excellent and the main fracture mechanism was void linking. When ln Z was below 32 s-1, the hot ductility was poor and fracture was mainly caused by grain boundary sliding. A fine grain structure is beneficial for homogenous deformation and dynamic recrystallization, which induces better hot ductility. The effect of M7C3 carbide particles dispersed in the matrix on the hot ductility was small. The grain growth kinetics in the 8 pct Cr steel were obtained between 1373 K and 1473 K (1100 °C and 1200 °C). Finally, optimized preheating and forging procedures for 8 pct Cr steel rollers are provided.

Detection of PCT and urinary β2 -MG enhances the accuracy for localization diagnosing pediatric urinary tract infection.

Science.gov (United States)

Fang, Jian; Luan, Jiangwei; Zhu, Gaohong; Qi, Chang; Wang, Dandan

2017-09-01

The purpose of this article was to investigate whether the combination of urinary beta 2 microglobulin (urinary β 2 -MG) and procalcitonin (PCT) diagnosis could enhance the localization diagnostic precision of pediatric urinary tract infection comparing with single diagnosis. A study was conducted in the Nephrology Department of Wuhan women and children's health care centre. This study incorporated 85 participants, including 35 children who were diagnosed as upper urinary tract infection (UUTI) with the symptom of fever and 50 children who conducted lower urinary tract infection (LUTI). Levels of PCT and urinary β 2 -MG in both UUTI and LUTI patients were measured and compared. The level of PCT and β 2 -MG were both significantly higher in UUTI group compared with in LUTI group. AUC of urinary β 2 -MG ROC (sensitivity of 71.4%, specificity of 90.0%) was significantly smaller than that of PCT ROC (sensitivity of 77.1%, specificity of 96.0%) in the single diagnosis. Although in the combined diagnosis, the sensitivity and specificity increased to 88.6% and 98%, respectively. Both PCT and β 2 -MG could be used to localize the UTI. Introducing urinary β 2 -MG into PCT diagnosis could increase the sensitivity and specificity of UTI lesion diagnosis in clinical practice. © 2016 The Authors Journal of Clinical Laboratory Analysis Published by Wiley Periodicals, Inc.

Effects of container material on PCT leach test results for high-level nuclear waste glasses

International Nuclear Information System (INIS)

Xing, S.B.; Pegg, I.L.

1994-01-01

A glass-based waste form used for the immobilization of high-level nuclear wastes should exhibit good resistance to aqueous corrosion since typically this is the primary process by which radionucleides could be released into the environment upon failure of other barriers. In the USA, the Waste Acceptance Product Specifications (WAPS) provides a set of requirements to ensure the consistency of the waste forms produced and specifies the Product Consistency Test (PCT) as a measure of relative chemical durability. While the PCT procedure permits usage of both Teflon and stainless steel vessels for testing of simulated development glasses, Teflon is not permitted for testing of production glasses due to radiative degradation. The results presented in this paper indicate that there are very significant differences between tests conducted in the two types of vessels due to the well-known permeability of Teflon to atmospheric carbon dioxide which results in lowering of the solution pH and a consequent reduction in the leach rate of silicate glasses. A wide range of nuclear waste glass compositions was subjected to the PCT procedure using both Teflon and stainless steel vessels. The magnitude of the effect (up to a factor of four for B, Na, Li concentrations) depends strongly on glass composition, therefore the isolated checks performed previously were inconclusive. The permeability to CO, of two types of Teflon vessels specified in the PCT procedure was directly measured using buffer solutions: ingress of CO, is linear in time, strongly pH-dependent, and was as high as 100 ppm after 7 days. In actual PCT tests in Teflon vessels, the total CO, content was 560 ppm after 87 days and 1930 ppm after one year

Assessment of the Effects on PCT Evaluation of Enhanced Fuel Model Facilitated by Coupling the MARS Code with the FRAPTRAN Code

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyong Chol; Lee, Young Jin; Han, Sam Hee [NSE Technology Inc., Daejeon (Korea, Republic of)

2016-10-15

The principal objectives of the two safety criteria, peak cladding temperature (PCT) and total oxidation limits, are to ensure that the fuel rod claddings remain sufficiently ductile so that they do not crack and fragment during a LOCA. Another important purpose of the PCT limit is to ensure that the fuel cladding does not enter the regime of runaway oxidation and uncontrollable heat-up. However, even when the PCT limit is satisfied, it is known that cladding failures may still occur in a certain percentage of the fuel rods during a LOCA. This is largely because a 100% fuel failure is assumed for the radiological consequence analysis in the US regulatory practices. In this study, we analyze the effects of cladding failure and other fuel model features on PCT during a LOCA using the MARS-FRAPTRAN coupled code. MARS code has been coupled with FRAPTRAN code to extend fuel modeling capability. The coupling allows feedback of FRAPTRAN results in real time. Because of the significant impact of fuel models on key safety parameters such as PCT, detailed and accurate fuel models should be employed when evaluating PCT in LOCA analysis. It is noteworthy that the ECCS evaluation models laid out in the Appendix K to 10CFR50 require a provision for predicting cladding swelling and rupture and require to assume that the inside of the cladding react with steam after the rupture. The metal-water reaction energy can have significantly large effect on the reflood PCT, especially when fuel failure occurs. Effects of applying an advanced fuel model on the PCT evaluation can be clearly seen when comparing the MARS and the FRAPTRAN results in both the one-way calculation and the feedback calculation. As long as MARS and FRAPTRAN are used respectively in the ranges where they have been validated, the coupled calculation results are expected to be valid and to reveal various aspects of phenomena which have not been discovered in previous uncoupled calculations by MARS or FRAPTRAN.

Heat treatment for improvement in lower temperature mechanical properties of 0.40 pct C-Cr-Mo ultrahigh strength steel

Science.gov (United States)

Tomita, Yoshiyuki; Okabayashi, Kunio

1983-11-01

In the previous paper, it was reported that isothermal heat treatment of a commercial Japanese 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel (AISI 4340 type) at 593 K for a short time followed by water quenching, in which a mixed structure of 25 vol pct lower bainite and 75 vol pct martensite is produced, results in the improvement of low temperature mechanical properties (287 to 123 K). The purpose of this paper is to study whether above new heat treatment will still be effective in commercial practice for improving low temperature mechanical properties of the ultrahigh strength steel when applied to a commercial Japanese 0.40 pct C-Cr-Mo ultrahigh strength steel which is economical because it lacks the expensive nickel component (AISI 4140 type). At and above 203 K this new heat treatment, as compared with the conventional 1133 K direct water quenching treatment, significantly improved the strength, tensile ductility, and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel. At and above 203 K the new heat treatment also produced superior fracture ductility and notch toughness results at similar strength levels as compared to those obtained by using γ α' repetitive heat treatment for the same steel. However, the new heat treatment remarkably decreased fracture ductility and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel below 203 K, and thus no significant improvement in the mechanical properties was noticeable as compared with the properties produced by the conventional 1133 K direct water quenching treatment and the γ α' repetitive heat treatment. This contrasts with the fact that the new heat treatment, as compared with the conventional 1133 K direct water quenching treatment and the γ α' repetitive heat treatment, dramatically improved the notch toughness of the 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel, providing a better combination of strength and ductility throughout the 287 to 123 K temperature range. The difference

Risk-informed analysis of the large break loss of coolant accident and PCT margin evaluation with the RISMC methodology

International Nuclear Information System (INIS)

Liang, T.H.; Liang, K.S.; Cheng, C.K.; Pei, B.S.; Patelli, E.

2016-01-01

Highlights: • With RISMC methodology, both aleatory and epistemic uncertainties have been considered. • 14 probabilistically significant sequences have been identified and quantified. • A load spectrum for LBLOCA has been conducted with CPCT and SP of each dominant sequence. • Comparing to deterministic methodologies, the risk-informed PCT margin can be greater by 44–62 K. • The SP of the referred sequence to cover 99% in the load spectrum is only 5.07 * 10 −3 . • The occurrence probability of the deterministic licensing sequence is 5.46 * 10 −5 . - Abstract: For general design basis accidents, such as SBLOCA and LBLOCA, the traditional deterministic safety analysis methodologies are always applied to analyze events based on a so called surrogate or licensing sequence, without considering how low this sequence occurrence probability is. In the to-be-issued 10 CFR 50.46a, the LBLOCA will be categorized as accidents beyond design basis and the PCT margin shall be evaluated in a risk-informed manner. According to the risk-informed safety margin characterization (RISMC) methodology, a process has been suggested to evaluate the risk-informed PCT margin. Following the RISMC methodology, a load spectrum of PCT for LBLOCA has been generated for the Taiwan’s Maanshan Nuclear Power plant and 14 probabilistic significant sequences have been identified. It was observed in the load spectrum that the conditional PCT generally ascends with the descending sequence occurrence probability. With the load spectrum covering both aleatory and epistemic uncertainties, the risk-informed PCT margin can be evaluated by either expecting value estimation method or sequence probability coverage method. It was found that by comparing with the traditional deterministic methodology, the PCT margin evaluated by the RISMC methodology can be greater by 44–62 K. Besides, to have a cumulated occurrence probability over 99% in the load spectrum, the occurrence probability of the

Risk-informed analysis of the large break loss of coolant accident and PCT margin evaluation with the RISMC methodology

Energy Technology Data Exchange (ETDEWEB)

Liang, T.H. [Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Liang, K.S., E-mail: ksliang@alum.mit.edu [Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Cheng, C.K.; Pei, B.S. [Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Patelli, E. [Institute of Risk and Uncertainty, University of Liverpool, Room 610, Brodie Tower, L69 3GQ (United Kingdom)

2016-11-15

Highlights: • With RISMC methodology, both aleatory and epistemic uncertainties have been considered. • 14 probabilistically significant sequences have been identified and quantified. • A load spectrum for LBLOCA has been conducted with CPCT and SP of each dominant sequence. • Comparing to deterministic methodologies, the risk-informed PCT margin can be greater by 44–62 K. • The SP of the referred sequence to cover 99% in the load spectrum is only 5.07 * 10{sup −3}. • The occurrence probability of the deterministic licensing sequence is 5.46 * 10{sup −5}. - Abstract: For general design basis accidents, such as SBLOCA and LBLOCA, the traditional deterministic safety analysis methodologies are always applied to analyze events based on a so called surrogate or licensing sequence, without considering how low this sequence occurrence probability is. In the to-be-issued 10 CFR 50.46a, the LBLOCA will be categorized as accidents beyond design basis and the PCT margin shall be evaluated in a risk-informed manner. According to the risk-informed safety margin characterization (RISMC) methodology, a process has been suggested to evaluate the risk-informed PCT margin. Following the RISMC methodology, a load spectrum of PCT for LBLOCA has been generated for the Taiwan’s Maanshan Nuclear Power plant and 14 probabilistic significant sequences have been identified. It was observed in the load spectrum that the conditional PCT generally ascends with the descending sequence occurrence probability. With the load spectrum covering both aleatory and epistemic uncertainties, the risk-informed PCT margin can be evaluated by either expecting value estimation method or sequence probability coverage method. It was found that by comparing with the traditional deterministic methodology, the PCT margin evaluated by the RISMC methodology can be greater by 44–62 K. Besides, to have a cumulated occurrence probability over 99% in the load spectrum, the occurrence probability

Kinetics of Z-Phase Precipitation in 9 to 12 pct Cr Steels

DEFF Research Database (Denmark)

Danielsen, Hilmar Kjartansson; Nunzio, Paolo Emilio di; Hald, John

2013-01-01

precipitated Z-phase 20 to 50 times faster than the 9 pct Cr steel. Transmission electron microscopy (TEM) was applied to follow the Z-phase precipitation, using energy-dispersive X-ray spectroscopy (EDS) line scans and atomic resolution imaging. © The Minerals, Metals & Materials Society and ASM International...

PCT theorem for fields with arbitrary high-energy behavior

International Nuclear Information System (INIS)

Luecke, W.

1986-01-01

A neutral scalar field A(x) is considered that has to be smeared by Fourier transforms of C/sup infinity/ functions with compact support but otherwise fulfills all the Wightman axioms, except strict local commutativity. It is shown to fulfill the PCT symmetry condition (where Ω denotes the vacuum state vector) 1 ) xxx A(x/sub n/)Ω> = 1 )Ω> if and only if 1 ) xxx A(x/sub n/)Ω> - 1 )Ω> can be represented, in a sense, as an infinite sum of derivatives of measures with supports containing no Jost points

Expression of MMP-2 and TIMP-1 in cerebrospinal fluid and the correlation with dynamic changes of serum PCT in neonatal purulent meningitis

Science.gov (United States)

Chen, Huilan; Wu, Fei; Fu, Rong; Feng, Xiangchun

2018-01-01

Matrix metalloproteinase 2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels in cerebrospinal fluid of pediatric patients with neonatal purulent meningitis were observed to analyze changes in serum procalcitonin (PCT) and the correlation among the three factors (MMP-2, TIMP-1 and PCT). Sixty pediatric patients with neonatal purulent meningitis from April 2015 to December 2016 were enrolled as the purulent meningitis group and 60 pediatric patients with viral encephalitis treated during the same period were enrolled as the viral encephalitis group. Additionally, 60 healthy newborns who underwent physical examinations in our hospital during the same period were enrolled as the control group. The levels of MMP-2 were 136.73±25.42 ng/ml in the purulent meningitis group, 45.32±6.57 ng/ml in the viral encephalitis group and 1.32±0.51 ng/ml in the control group and the differences between the three groups were statistically significant (F=15.052, pfluid were 374.55±36.04 ng/ml in the purulent meningitis group, 176.61±21.06 ng/ml in the viral encephalitis group and 7.72±2.44 ng/ml in the control group. The serum levels of PCT were 14.56±2.21 ng/ml in the purulent meningitis group, 9.04±1.17 ng/ml in the viral encephalitis group and 0.38±0.14 ng/ml in the control group. The level of MMP-2 in cerebrospinal fluid of pediatric patients in the purulent meningitis group was positively correlated with the level of serum PCT (r=0.582, pfluid of pediatric patients in the viral encephalitis group was positively correlated with the level of serum PCT (r=0.635, p<0.05). In conclusion, MMP-2 and TIMP-1 were positively correlated with the levels of serum PCT, suggesting that MMP-2, TIMP-1 and PCT were involved in the occurrence and development of neonatal purulent meningitis. PMID:29399119

The use of a standardized PCT-algorithm reduces costs in intensive care in septic patients - a DRG-based simulation model

Directory of Open Access Journals (Sweden)

Wilke MH

2011-12-01

Full Text Available Abstract Introduction The management of bloodstream infections especially sepsis is a difficult task. An optimal antibiotic therapy (ABX is paramount for success. Procalcitonin (PCT is a well investigated biomarker that allows close monitoring of the infection and management of ABX. It has proven to be a cost-efficient diagnostic tool. In Diagnoses Related Groups (DRG based reimbursement systems, hospitals get only a fixed amount of money for certain treatments. Thus it's very important to obtain an optimal balance of clinical treatment and resource consumption namely the length of stay in hospital and especially in the Intensive Care Unit (ICU. We investigated which economic effects an optimized PCT-based algorithm for antibiotic management could have. Materials and methods We collected inpatient episode data from 16 hospitals. These data contain administrative and clinical information such as length of stay, days in the ICU or diagnoses and procedures. From various RCTs and reviews there are different algorithms for the use of PCT to manage ABX published. Moreover RCTs and meta-analyses have proven possible savings in days of ABX (ABD and length of stay in ICU (ICUD. As the meta-analyses use studies on different patient populations (pneumonia, sepsis, other bacterial infections, we undertook a short meta-analyses of 6 relevant studies investigating in sepsis or ventilator associated pneumonia (VAP. From this analyses we obtained savings in ABD and ICUD by calculating the weighted mean differences. Then we designed a new PCT-based algorithm using results from two very recent reviews. The algorithm contains evidence from several studies. From the patient data we calculated cost estimates using German National standard costing information for the German G-DRG system. We developed a simulation model where the possible savings and the extra costs for (in average 8 PCT tests due to our algorithm were brought into equation. Results We calculated ABD

Quantum fields on manifolds: PCT and gravitationally induced thermal states

International Nuclear Information System (INIS)

Sewell, G.L.

1982-01-01

We formulate an axiomatic scheme, designed to provide a framework for a general, rigorous theory of relativistic quantum fields on a class of manifolds, that includes Kruskal's extension of Schwarzchild space-time, as well as Minkowski space-time. The scheme is an adaptation of Wightman's to this class of manifolds. We infer from it that, given an arbitrary field (in general, interacting) on a manifold X, the restriction of the field to a certain open submanifold X/sup( + ), whose boundaries are event horizons, satisfies the Kubo--Martin--Schwinger (KMS) thermal equilibrium conditions. This amounts to a rigorous, model-independent proof of a generalized Hawking--Unruh effect. Further, in cases where the field enjoys a certain PCT symmetry, the conjugation governing the KMS condition is just the PCT operator. The key to these results is an analogue, that we prove, of the Bisognano--Wichmann theorem [J. Math. Phys. 17, (1976), Theorem 1]. We also construct an alternative scheme by replacing a regularity condition at an event horizon by the assumption that the field in X/sup( + ) is in a ground, rather then a thermal, state. We show that, in this case, the observables in X/sup( + ) are uncorrelated to those in its causal complement, X/sup( - ), and thus that the event horizons act as physical barriers. Finally, we argue that the choice between the two schemes must be dictated by the prevailing conditions governing the state of the field

Should the post-coital test (PCT) be part of the routine fertility work-up?

NARCIS (Netherlands)

van der Steeg, Jan W.; Steures, Pieternel; Eijkemans, Marinus J. C.; Habbema, J. Dik; van der Veen, Fulco; Bossuyt, Patrick M. M.; Hompes, Peter G. A.; Mol, Ben W. J.

2004-01-01

BACKGROUND: This study aimed to determine whether medical history and semen analysis can predict the result of the post-coital test (PCT). METHODS: A previously reported data set of Dutch patients collected between 1985 and 1993 was used. Our study was limited to just patients with an ovulatory

Unusual morphology of the omega phase in a Zr-1.75 At. pct Ni alloy

International Nuclear Information System (INIS)

Srivastava, D.; Mukhopadhyay, P.; Ramadasan, E.; Banerjee, S.

1993-01-01

The observations reported in the present communication were made in the course of a microstructural investigation on dilute Zr-Ni alloys. The alloys were prepared from nuclear-grade sponge zirconium and high-purity nickel by nonconsumable arc melting. Repeated melting was carried out to enhance homogeneity. A master alloy was used in the preparation of very dilute alloys. The observations reported here clearly indicate that the formation of the ω phase on β quenching, can occur in the binary Zr-Ni system at very low solute concentrations, suggesting that nickel is a strong ω stabilizer. Such a situation is known to obtain in the binary Zr-Mo system also. However, the unusual ω morphology observed in the present work has not been reported in the context of dilute Zr-Mo alloys. The appearance of sharp ω reflections and the absence of streaking and diffuse distributions in the selected area electron diffraction (SAD) patterns suggest that the Zr-1.75 at. pct Ni composition lies toward the solute lean end of the composition range associated with the formation of the athermal ω phase in the binary Zr-Ni system. In a more dilute Zr-Ni alloy (Zr-1.30 at. pct Ni), no athermal ω could be observed in β quenched specimens. The absence of streaking is also consistent with the fact that the ω phase in the β quenched Zr-1.75 at. pct Ni alloy did not occur in the form of very fine precipitates. The unusual ω morphology encountered in this work merits further investigation

Dilatometric and dielectric behaviour of Sm modified PCT ceramics

International Nuclear Information System (INIS)

Singh, Sarabjit; Thakur, O.P.; Prakash, Chandra; Raina, K.K.

2005-01-01

Samarium modified PCT ceramics with composition (Pb 0.76-x Sm x Ca 0.24 )(Ti 0.98 Mn 0.02 )O 3 ; x=0-0.08 in steps of 0.02 were prepared by conventional mixed-oxide method. Detailed dilatometric studies were carried out for green specimens in order to study sintering behaviour. Change in the dilatometric behaviour is correlated with the XRD results of powders calcined at different temperatures. Dielectric constant was observed to increase with increasing Sm concentration, which has been attributed to reduced tetragonality and better densification on Sm substitution. SEM micrographs have revealed the grain size of the samples. Ferroelectric hysteresis behaviour was studied for all the compositions

Perfusion of prostate cancer: correlation between p-CT and whole-mount pathology - case report

International Nuclear Information System (INIS)

Luczynska, E.; Aniol, J.; Szczudlo, J.; Stelmach, A.; Jaszczynski, J.; Hartel, M.; Konopka, M.

2006-01-01

Prostate cancer is the second most common form of cancer among malignant neoplasm for men in Poland, next to lung cancer, as far as frequency is concerned. Incidence of this kind of neoplasm increases by about 3 % annually. In the last decade a growing number of this type of diseases has been observed and its detections are closely related to the development of biochemical (PSA - prostate-specific antigen) and diagnostic imaging technologies. A 60-year-old patient was diagnosed in the Oncology Institute because of an increasing level of PSA in his blood. The PSA level in March 2005 was 10,4 ng/ml. There was a slight increase of PSA during the year, up to 1,5 ng/ml (this is less than 25% / year). The patient came for the following check up to repeat the core-needle sextant biopsy, to exclude neoplasmatic process. Before operation the patient's prostate was tested by p-CT. The parametric maps revealed some disturbances of blood flow parameters. Blood flow - BF, blood volume - BV, mean transit time - MTT and permeability surface - PS were noted in the form of their asymmetry within peripheral zone in the right lobe. A pathological focus with increased BF, BV, PS and decreased MTT was revealed on the right side. This examination suggested that neoplasmatic process might be localized in this area. Core needle biopsy taken from the suspicious region revealed prostate cancer. That was also confirmed in histopathology examination after radical prostatectomy. P-CT examination can be performed during classical CT exam and it leads to obtaining morphological and functional data at the same time. P-CT examination allowed us to localize pathological process and helped to continue its verification by other diagnostic methods. (author)

Utility of Procalcitonin (PCT and Mid regional pro-Adrenomedullin (MR-proADM in risk stratification of critically ill febrile patients in Emergency Department (ED. A comparison with APACHE II score

Directory of Open Access Journals (Sweden)

Travaglino Francesco

2012-08-01

Full Text Available Abstract Background The aim of our study was to evaluate the prognostic value of MR-proADM and PCT levels in febrile patients in the ED in comparison with a disease severity index score, the APACHE II score. We also evaluated the ability of MR-proADM and PCT to predict hospitalization. Methods This was an observational, multicentric study. We enrolled 128 patients referred to the ED with high fever and a suspicion of severe infection such as sepsis, lower respiratory tract infections, urinary tract infections, gastrointestinal infections, soft tissue infections, central nervous system infections, or osteomyelitis. The APACHE II score was calculated for each patient. Results MR-proADM median values in controls were 0.5 nmol/l as compared with 0.85 nmol/l in patients (P P . MR-proADM and PCT levels were significantly increased in accordance with the Apache II quartiles (P  respectively. In the respiratory infections, urinary infections, and sepsis-septic shock groups we found a correlation between the Apache II and MR-proADM respectively and MR-proADM and PCT respectively. We evaluated the ability of MR-proADM and PCT to predict hospitalization in patients admitted to our emergency departments complaining of fever. MR-proADM alone had an AUC of 0.694, while PCT alone had an AUC of 0.763. The combined use of PCT and MR-proADM instead showed an AUC of 0.79. Conclusions The present study highlights the way in which MR-proADM and PCT may be helpful to the febrile patient’s care in the ED. Our data support the prognostic role of MR-proADM and PCT in that setting, as demonstrated by the correlation with the APACHE II score. The combined use of the two biomarkers can predict a subsequent hospitalization of febrile patients. The rational use of these two molecules could lead to several advantages, such as faster diagnosis, more accurate risk stratification, and optimization of the treatment, with consequent benefit to the patient and

Nonlinear relationship between the Product Consistency Test (PCT) response and the Al/B ratio in a soda-lime aluminoborosilicate glass

Energy Technology Data Exchange (ETDEWEB)

Farooqi, Rahmat Ullah, E-mail: rufarooqi@postech.ac.kr [Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784 (Korea, Republic of); Hrma, Pavel [Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784 (Korea, Republic of); Pacific Northwest National Laboratory, Richland, WA (United States)

2016-06-15

We have investigated the effect of Al/B ratio on the Product Consistency Test (PCT) response. In an aluminoborosilicate soda-lime glass based on a modified International Simple Glass, ISG-3, the Al/B ratio varied from 0 to 0.55 (in mole fractions). In agreement with various models of the PCT response as a function of glass composition, we observed a monotonic increase of B and Na releases with decreasing Al/B mole ratio, but only when the ratio was higher than 0.05. Below this value (Al/B < 0.05), we observed a sharp decrease that we attribute to B in tetrahedral coordination.

Microanalysis on the Hydrogen Ion Irradiated 50 wt pct TiC-C Films

Institute of Scientific and Technical Information of China (English)

Hui JIANG; Yaoguang LIU; Ningkang HUANG

2007-01-01

The 50 wt pct TiC-C films were prepared on stainless steel substrates by using a technique of ion beam mixing.These films were irradiated by hydrogen ion beam with a dose of 1×1018 ions/cm2 and an energy of 5 keV.Microanalysis of X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) were used to analyze the films before and after hydrogen ion irradiation and to study the mechanism of hydrogen resistance.

Hvornår har 1.000 landbrug 90 pct. af landbrugsjorden?

DEFF Research Database (Denmark)

Hansen, Henning Otte

2017-01-01

relativt lige i forhold til resten af EU. De 1.000 største landbrug driver ca. 22 pct. af landbrugsjorden, og andelen er stigende. Selv om strukturudviklingen ser ud til at fortsætte upåvirket af de økonomiske og markedsmæssige forhold, kan man identificere en række forhold, som er drivkræfter bag...... strukturudviklingen. De senere års liberalisering af landbrugsloven har sandsynligvis været med til fremme strukturudviklingen yderligere, og også fjernelsen af EU‘s mælkekvoter ser ud til at have genskabt den hidtidige udvikling. Om strukturudviklingen er en fordel eller en ulempe kan ikke afgøres entydigt, idet...

Application of the methodology of surface of answer in the determination of the PCT in the simulation of a LOFT; Aplicacion de la metodologia de superficies de respuesta en la determinacion del PCT en la simulacion de un LOFT

Energy Technology Data Exchange (ETDEWEB)

Alva N, J. [IPN, Escuela Superior de Fisica y Matematicas, Departamento de Ingenieria Nuclear, Av. IPN s/n, Col. Lindavista, Mexico 07738 D.F. (Mexico); Ortiz V, J.; Amador G, R. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: neriaesfm@gmail.com

2008-07-01

This article summarizes the main typical of the methodology of surfaces and answer (MSA) and its connections with the lineal regression analysis. Also, an example of the application of MSA in the prediction of the principle cladding temperature (PCT) of a combustible assembly of a nuclear reactor, whose used data were taken from the simulation of a LOFT (Loss Of Fluid Test) during a course of experts. The made prediction will be used like one first approach to predict the behavior of the PCT, this is made in order to diminish the time of calculation when realizing the executions of codes thermal hydraulics of better estimation. The present work comprises of the theoretical base of the project in charge to delineate a methodology of uncertainty analysis for codes of better estimation, employees in the thermal hydraulics analysis and safety of plants and nuclear reactors. The institutions that participate in such project are: ININ, CFE, IPN and CNSNS, is possible to mention that this project is sponsored by the IAEA. (Author)

Portable Computer Technology (PCT) Research and Development Program Phase 2

Science.gov (United States)

Castillo, Michael; McGuire, Kenyon; Sorgi, Alan

1995-01-01

The subject of this project report, focused on: (1) Design and development of two Advanced Portable Workstation 2 (APW 2) units. These units incorporate advanced technology features such as a low power Pentium processor, a high resolution color display, National Television Standards Committee (NTSC) video handling capabilities, a Personal Computer Memory Card International Association (PCMCIA) interface, and Small Computer System Interface (SCSI) and ethernet interfaces. (2) Use these units to integrate and demonstrate advanced wireless network and portable video capabilities. (3) Qualification of the APW 2 systems for use in specific experiments aboard the Mir Space Station. A major objective of the PCT Phase 2 program was to help guide future choices in computing platforms and techniques for meeting National Aeronautics and Space Administration (NASA) mission objectives. The focus being on the development of optimal configurations of computing hardware, software applications, and network technologies for use on NASA missions.

Microstructures and Surface Stabilities of {Ni-0.4C-6Ta- xCr, 0 ≤ x ≤ 50 Wt Pct} Cast Alloys at High Temperature

Science.gov (United States)

Berthod, Patrice

2018-06-01

Nickel-based cast alloys rich in chromium and reinforced by TaC carbides are potentially very interesting alloys for applications at elevated temperatures. Unfortunately, unlike cobalt-chromium and iron-chromium alloys, it is difficult to obtain exclusively TaC as primary carbides in Ni-Cr alloys. In alloys containing 30 wt pct Cr tantalum, carbides coexist with chromium carbides. The latter tend to weaken the alloy at elevated temperatures because they become rapidly spherical and then quickly lose their reinforcing effect. In this work, we attempted to stabilize TaC as a single carbide phase by testing different chromium contents in the [0, 50 wt pct] range. Six alloys containing 0.4C and 6Ta, weight contents corresponding to equivalent molar contents, were elaborated by foundry, and their as-cast microstructures were characterized. Samples of all alloys were exposed to 1127 °C and 1237 °C for 24 hours to characterize their stabilized microstructures. The surface fractions of chromium carbides and tantalum carbides were measured by image analysis, and their evolutions vs the chromium content were studied. For the chosen C and Ta contents, it appears that obtaining TaC only is possible by decreasing the chromium content to 10 wt pct. At the same time, TaC fractions are unfortunately too low because a large portion of tantalum integrates into the solid solution in the matrix. A second consequence is a critical decrease in oxidation resistance. Other possible methods to stabilize TaC as a single carbide are evocated, such as the simultaneous increase in Ta and decrease in chromium from 30 wt pct Cr.

Development of an ASTM standard glass durability test, the Product Consistency Test (PCT), for high level radioactive waste glass

International Nuclear Information System (INIS)

Jantzen, C.M.; Bibler, N.E.; Beam, D.C.; Ramsey, W.G.

1994-01-01

The nation's first, and the world's largest, facility to immobilize high-level nuclear waste in durable borosilicate glass has started operation at the Savannah River Site (SRS) in Aiken, South Carolina. The product specifications on the glass wasteform produced in the Defense Waste Processing Facility (DWPF) required extensive characterization of the glass product before actual production began and for continued characterization during production. To aid in this characterization, a glass durability (leach) test was needed that was easily reproducible, could be performed remotely on highly radioactive samples, and could yield results rapidly. Several standard leach tests were examined with a variety of test configurations. Using existing tests as a starting point, the DWPF Product Consistency Test (PCT was developed in which crushed glass samples are exposed to 90 ± 2 degree C deionized water for seven days. Based on extensive testing, including a seven-laboratory round robin and confirmatory testing with radioactive samples, the PCT is very reproducible, yields reliable results rapidly, and can be performed in shielded cell facilities with radioactive samples

Resting functional imaging tools (MRS, SPECT, PET and PCT).

Science.gov (United States)

Van Der Naalt, J

2015-01-01

Functional imaging includes imaging techniques that provide information about the metabolic and hemodynamic status of the brain. Most commonly applied functional imaging techniques in patients with traumatic brain injury (TBI) include magnetic resonance spectroscopy (MRS), single photon emission computed tomography (SPECT), positron emission tomography (PET) and perfusion CT (PCT). These imaging modalities are used to determine the extent of injury, to provide information for the prediction of outcome, and to assess evidence of cerebral ischemia. In TBI, secondary brain damage mainly comprises ischemia and is present in more than 80% of fatal cases with traumatic brain injury (Graham et al., 1989; Bouma et al., 1991; Coles et al., 2004). In particular, while SPECT measures cerebral perfusion and MRS determines metabolism, PET is able to assess both perfusion and cerebral metabolism. This chapter will describe the application of these techniques in traumatic brain injury separately for the major groups of severity comprising the mild and moderate to severe group. The application in TBI and potential difficulties of each technique is described. The use of imaging techniques in children will be separately outlined. © 2015 Elsevier B.V. All rights reserved.

Application of the methodology of surface of answer in the determination of the PCT in the simulation of a LOFT

International Nuclear Information System (INIS)

Alva N, J.; Ortiz V, J.; Amador G, R.

2008-01-01

This article summarizes the main typical of the methodology of surfaces and answer (MSA) and its connections with the lineal regression analysis. Also, an example of the application of MSA in the prediction of the principle cladding temperature (PCT) of a combustible assembly of a nuclear reactor, whose used data were taken from the simulation of a LOFT (Loss Of Fluid Test) during a course of experts. The made prediction will be used like one first approach to predict the behavior of the PCT, this is made in order to diminish the time of calculation when realizing the executions of codes thermal hydraulics of better estimation. The present work comprises of the theoretical base of the project in charge to delineate a methodology of uncertainty analysis for codes of better estimation, employees in the thermal hydraulics analysis and safety of plants and nuclear reactors. The institutions that participate in such project are: ININ, CFE, IPN and CNSNS, is possible to mention that this project is sponsored by the IAEA. (Author)

An examination of the interparticle contact area during sintering of W-0.3 wt pct Co

International Nuclear Information System (INIS)

Mitlin, D.; German, R.M.

1998-01-01

As a powder compact sinters, its microstructure evolves. One way to quantify the scale of the microstructure is to consider the interparticle contact area. This study examines two known models for calculating the interparticle contact area: the classic two-sphere model and the Voronoi cell model. Both models have particular assumptions about the microstructure that make them not applicable for treating densification to near full density with concurrent grain growth. The classic two-sphere model assumes a regular packing of particles and a perfectly spherical particle geometry and neglects an increasing particle coordination number with sintering. The Voronoi cell model assumes that the scale of the microstructure remains constant; i.e., as long as the compact is densifying, grain growth does not occur. The authors propose a modified Voronoi cell that accounts for an increasing grain size, making it applicable to a general case where grain growth occurs during sintering. The three models are compared to the interparticle contact area data, obtained by stereology techniques, for W-0.3 wt pct Co sintered from green state to near full density. The original Voronoi cell model fits the data only at low temperatures, before the onset of grain growth. Below approximately 90 pct relative density, the two-sphere model with an assumed coordination number of six (coordination number in a green compact) and the modified Voronoi cell model provide a good fit to the data. At higher densities, both models overestimate the interparticle contact area

A PCT algorithm for discontinuation of antibiotic therapy is a cost-effective way to reduce antibiotic exposure in adult intensive care patients with sepsis

NARCIS (Netherlands)

Kip, Michelle Maria Aleida; Kusters, Ron; IJzerman, Maarten Joost; Steuten, Lotte Maria Gertruda

2015-01-01

Objective: Procalcitonin (PCT) is a specific marker for differentiating bacterial from non-infective causes of inflammation. It can be used to guide initiation and duration of antibiotic therapy in intensive care unit (ICU) patients with suspected sepsis, and might reduce the duration of hospital

Effect of Boron Addition on Microstructural Evolution and Room-Temperature Mechanical Properties of Novel Fe66- x CrNiB x Si ( x = 0, 0.25, 0.50 and 0.75 Wt Pct) Advanced High-Strength Steels

Science.gov (United States)

Askari-Paykani, Mohsen; Shahverdi, Hamid Reza; Miresmaeili, Reza

2016-11-01

In this study, the Vickers hardnesses and room-temperature uniaxial tensile behaviors of four Fe66- x CrNiB x Si ( x = 0 (0B), 0.25 (25B), 0.50 (50B), and 0.75 (75B) wt pct) advanced high-strength steels (AHSSs) in the as-hot-rolled and heat-treated (1373 K (1100 °C)/2 h + 973 K (700 °C)/20 min) conditions were investigated. Microstructural evolution after solidification, hot rolling, heat treatment, and uniaxial tensile tests of 0B, 25B, 50B, and 75B AHSSs was also characterized using field emission gun scanning electron microscopy and X-ray diffraction. The tensile behaviors of the 0B, 25B, 50B, and 75B AHSSs were manifested by an excellent combination of strength and ductility over 34.7 and 47.1 GPa pct, 36.9 and 42.3 GPa pct, 45.9 and 46.4 GPa pct, and 11.9 and 47.8 GPa pct, respectively, arising from microband-induced plasticity in the 0B, 50B, and 75B AHSSs and transformation-induced plasticity in the 25B specimens. All specimens in the as-hot-rolled and heat-treated states showed an austenitic matrix grain. Adding boron to the base alloy (0B) resulted in grain refinement, M2B dispersion, precipitation hardening, and solid solution strengthening, which led to an increase in strength. The results of the present work show promise for automotive applications that require excellent properties and reduced specific weight.

The diagnostic value of CRP, IL-8, PCT, and sTREM-1 in the detection of bacterial infections in pediatric oncology patients with febrile neutropenia

NARCIS (Netherlands)

Miedema, Karin G. E.; de Bont, Eveline S. J. M.; Elferink, Rob F. M. Oude; van Vliet, Michel J.; Nijhuis, Claudi S. M. Oude; Kamps, Willem A.; Tissing, Wim J. E.

2011-01-01

In this study, we evaluated C-reactive protein (CRP), interleukin (IL)-8, procalcitonin (PCT), and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) as predictors for bacterial infection in febrile neutropenia, plus their usefulness in febrile neutropenia during chemotherapy-induced

Corrosion Resistance Behavior of Single-Layer Cathodic Arc PVD Nitride-Base Coatings in 1M HCl and 3.5 pct NaCl Solutions

Science.gov (United States)

Adesina, Akeem Yusuf; Gasem, Zuhair M.; Madhan Kumar, Arumugam

2017-04-01

The electrochemical behavior of single-layer TiN, CrN, CrAlN, and TiAlN coatings on 304 stainless steel substrate, deposited using state-of-the-art and industrial size cathodic arc PVD machine, were evaluated in 1M HCl and 3.5 pct NaCl solutions. The corrosion behavior of the blank and coated substrates was analyzed by electrochemical impedance spectroscopy (EIS), linear polarization resistance, and potentiodynamic polarization. Bond-coat layers of pure-Ti, pure-Cr, alloyed-CrAl, and alloyed-TiAl for TiN, CrN, CrAlN, and TiAlN coatings were, respectively, first deposited for improved coating adhesion before the actual coating. The average coating thickness was about 1.80 µm. Results showed that the corrosion potentials ( E corr) of the coated substrates were shifted to more noble values which indicated improvement of the coated substrate resistance to corrosion susceptibility. The corrosion current densities were lower for all coated substrates as compared to the blank substrate. Similarly, EIS parameters showed that these coatings possessed improved resistance to defects and pores in similar solution compared to the same nitride coatings developed by magnetron sputtering. The charge transfer resistance ( R ct) can be ranked in the following order: TiAlN > CrN > TiN > CrAlN in both media except in NaCl solution where R ct of TiN is lowest. While the pore resistance ( R po) followed the order: CrAlN > CrN > TiAlN > TiN in HCl solution and TiAlN > CrN > CrAlN > TiN in NaCl solution. It is found that TiAlN coating has the highest protective efficiencies of 79 and 99 pct in 1M HCl and 3.5 pct NaCl, respectively. SEM analysis of the corroded substrates in both media was also presented.

Atom-Probe Tomographic Investigation of Austenite Stability and Carbide Precipitation in a TRIP-Assisted 10 Wt Pct Ni Steel and Its Weld Heat-Affected Zones

Science.gov (United States)

Jain, Divya; Seidman, David N.; Barrick, Erin J.; DuPont, John N.

2018-04-01

Newly developed low-carbon 10 wt pct Ni-Mo-Cr-V martensitic steels rely on the Ni-enriched, thermally stable austenite [formed via multistep intercritical Quench-Lamellarization-Tempering ( QLT)-treatment] for their superior mechanical properties, specifically ballistic resistance. Critical to the thermal stability of austenite is its composition, which can be severely affected in the weld heat-affected zones (HAZs) and thus needs investigations. This article represents the first study of the nanoscale redistributions of C, Ni, and Mn in single-pass HAZ microstructures of QLT-treated 10 wt pct Ni steels. Local compositions of Ni-rich regions (representative of austenite compositions) in the HAZs are determined using site-specific 3-D atom-probe tomography (APT). Martensite-start temperatures are then calculated for these compositions, employing the Ghosh-Olson thermodynamic and kinetics approach. These calculations predict that austenite (present at high temperatures) in the HAZs is susceptible to a martensitic transformation upon cooling to room temperature, unlike the austenite in the QLT-treated base-metal. While C in the QLT-treated base-metal is consumed primarily in MC and M2C-type carbide precipitates (M is Mo, Cr, V), its higher concentration in the Ni-rich regions in the HAZs indicates the dissolution of carbide precipitates, particularly M2C carbide precipitates. The role of M2C carbide precipitates and austenite stability is discussed in relation to the increase in microhardness values observed in the HAZs, relative to the QLT-treated base-metal. Insights gained from this research on austenite stability and carbide precipitation in the single-pass HAZ microstructures will assist in designing multiple weld cycles for these novel 10 wt pct Ni steels.

Effect of Aluminum Coating on the Surface Properties of Ti-(~49 at. pct) Ni Alloy

Science.gov (United States)

Sinha, Arijit; Khan, Gobinda Gopal; Mondal, Bholanath; Majumdar, Jyotsna Dutta; Chattopadhyay, Partha Protim

2015-08-01

Stable porous layer of mixed Al2O3 and TiO2 has been formed on the Ti-(~49 at. pct) Ni alloy surface with an aim to suppress leaching of Ni from the alloy surface in contact with bio-fluid and to enhance the process of osseointegration. Aluminum coating on the Ni-Ti alloy surface prior to the anodization treatment has resulted in enhancement of depth and uniformity of pores. Thermal oxidation of the anodized aluminum-coated Ni-Ti samples has exhibited the formation of Al2O3 and TiO2 phases with dense porous structure. The nanoindentation and nanoscratch measurements have indicated a remarkable improvement in the hardness, wear resistance, and adhesiveness of the porous aluminum-coated Ni-Ti sample after thermal oxidation.

How TEM Projection Artifacts Distort Microstructure Measurements: A Case Study in a 9 pct Cr-Mo-V Steel

Science.gov (United States)

Monsegue, Niven; Reynolds, William T.; Hawk, Jeffrey A.; Murayama, Mitsuhiro

2014-08-01

Morphological data obtained from two-dimensional (2D) and three-dimensional (3D) transmission electron microscopy (TEM) observations were compared to assess the effects of TEM projection errors for submicron-size precipitates. The microstructure consisted of M23C6 carbides in a 9 pct Cr-Mo-V heat resistant steel before and after exposure to creep conditions. Measurements obtained from about 800 carbides demonstrate that particle size and spacing estimates made from 2D observations overestimate the more accurate values obtained from 3D reconstructions. The 3D analysis also revealed the M23C6 precipitates lengthen anisotropically along lath boundary planes, suggesting that coarsening during the early stage of creep in this alloy system is governed by grain boundary diffusion.

Effects of aging temperature on electrical conductivity and hardness of Cu-3 at. pct Ti alloy aged in a hydrogen atmosphere

KAUST Repository

Semboshi, S.

2011-08-01

To improve the balance of the electrical conductivity and mechanical strength for dilute Cu-Ti alloys by aging in a hydrogen atmosphere, the influence of aging temperature ranging from 673 K to 773 K (400 °C to 500 °C) on the properties of Cu-3 at. pct Ti alloy was studied. The Vickers hardness increases steadily with aging time and starts to fall at 3 hours at 773 K (500 °C), 10 hours at 723 K (450 °C), or over 620 hours at 673 K (400 °C), which is the same as the case of conventional aging in vacuum. The maximum hardness increases from 220 to 236 with the decrease of aging temperature, which is slightly lower than aging at the same temperature in vacuum. The electrical conductivity at the maximum hardness also increases from 18 to 32 pct of pure copper with the decrease of the temperature, which is enhanced by a factor of 1.3 to 1.5 in comparison to aging in vacuum. Thus, aging at 673 K (400 °C) in a hydrogen atmosphere renders fairly good balance of strength and conductivity, although it takes nearly a month to achieve. The microstructural changes during aging were examined by transmission electron microscopy (TEM) and atom-probe tomography (APT), it was confirmed that precipitation of the Cu4Ti phase occurs first and then particles of TiH2 form as the third phase, thereby efficiently removing the Ti solutes in the matrix.

Metabolic borderzone in acutely ischemic canine myocardium demonstrated by positron-CT (PCT)

International Nuclear Information System (INIS)

Schwaiger, M.; Hansen, H.; Selin, C.; Wittmer, S.; Barrio, J.; Schelbert, H.R.

1984-01-01

Acute coronary ligation in dogs results in an area of myocardial dysfunction that exceeds the area of subsequent necrosis suggesting the existence of an ischemic ''borderzone'' of reversibly injured myocardium. The authors tested this hypothesis in 9 closed chest dogs with C-11 plamitate (CPA) and serial PCT imaging after an LAD occlusion. Using a blood flow (MBF) image obtained with iv N-13 ammonia prior to CPA, regions of interest were assigned on the serial CPA cross-sectional images to the center (IC) and border (IB) of the ischemic segment and to control myocardium (CO). CPA uptake was closely related to MBF (r=0.88) implicating flow as a major determinant of CPA uptake. Clearance helftimes (T 1/2) and relative sizes (RS) of the early rapid phase on the C-11 tissue time activity curves were determined for IC, IB and CO. In IC, MBF, RS and T 1/2 were markedly depressed indicating impaired CPA utilization and oxidation. In IB, MBF was less than in CO though only insignificantly, while RS and T 1/2 were highly abnormal. The authors conclude that FFA metabolism in areas adjacent to ischemic segments but without significant MBF decreases in abnormal, presenting evidence for a metabolic borderzone which now can be identified noninvasively with positron emission tomography

Contraction Twinning Dominated Tensile Deformation and Subsequent Fracture in Extruded Mg-1Mn (Wt Pct) at Ambient Temperature

Science.gov (United States)

Chakkedath, A.; Maiti, T.; Bohlen, J.; Yi, S.; Letzig, D.; Eisenlohr, P.; Boehlert, C. J.

2018-03-01

Due to their excellent strength-to-weight ratio, Mg alloys are attractive for applications where weight savings are critical. However, the limited cold formability of wrought Mg alloys severely restricts their widespread usage. In order to study the role that deformation twinning might play in limiting the elongation-to-failure ({ɛ} f ), in-situ tensile tests along the extrusion axis of Mg-1Mn (wt pct) were performed at 323 K, 423 K, and 523 K. The alloy exhibited a strong basal texture such that most of the grains experienced compression along their -axis during deformation. At 323 K, fracture occurred at about 10 pct strain. Although basal, prismatic, and pyramidal slip activity was observed along with extension twinning, contraction twinning significantly influenced the deformation, and such twins evolved into {10{\\bar{1}} 1}-{10{\\bar{1}} 2} double twins. Crystal plasticity simulation showed localized shear deformation within the contraction twins and double twins due to the enhanced activity of basal slip in the reoriented twin volume. Due to this, the twin-matrix interface was identified to be a potential crack initiation site. Thus, contraction twins were considered to have led to the failure of the material at a relatively low strain, suggesting that this deformation mode is detrimental to the cold formability of Mg and its alloys. With increasing temperature, there was a significant decrease in the activity of contraction twinning as well as extension twinning, along with a decrease in the tensile strength and an increase in the {ɛ} f value. A combination of basal, prismatic, and pyramidal slips accounted for a large percentage of the observed deformation activity at 423 K and 523 K. The lack of contraction twinning was explained by the expected decrease in the critical resolved shear stress values for pyramidal slip, and the improved {ɛ} f values at elevated temperatures were attributed to the vanishing activity of contraction twinning.

Contraction Twinning Dominated Tensile Deformation and Subsequent Fracture in Extruded Mg-1Mn (Wt Pct) at Ambient Temperature

Science.gov (United States)

Chakkedath, A.; Maiti, T.; Bohlen, J.; Yi, S.; Letzig, D.; Eisenlohr, P.; Boehlert, C. J.

2018-06-01

Due to their excellent strength-to-weight ratio, Mg alloys are attractive for applications where weight savings are critical. However, the limited cold formability of wrought Mg alloys severely restricts their widespread usage. In order to study the role that deformation twinning might play in limiting the elongation-to-failure ({ɛ} _{ {f}}), in-situ tensile tests along the extrusion axis of Mg-1Mn (wt pct) were performed at 323 K, 423 K, and 523 K. The alloy exhibited a strong basal texture such that most of the grains experienced compression along their -axis during deformation. At 323 K, fracture occurred at about 10 pct strain. Although basal, prismatic, and pyramidal slip activity was observed along with extension twinning, contraction twinning significantly influenced the deformation, and such twins evolved into {10{\\bar{1}}1}-{10{\\bar{1}}2} double twins. Crystal plasticity simulation showed localized shear deformation within the contraction twins and double twins due to the enhanced activity of basal slip in the reoriented twin volume. Due to this, the twin-matrix interface was identified to be a potential crack initiation site. Thus, contraction twins were considered to have led to the failure of the material at a relatively low strain, suggesting that this deformation mode is detrimental to the cold formability of Mg and its alloys. With increasing temperature, there was a significant decrease in the activity of contraction twinning as well as extension twinning, along with a decrease in the tensile strength and an increase in the {ɛ} _{ {f}} value. A combination of basal, prismatic, and pyramidal slips accounted for a large percentage of the observed deformation activity at 423 K and 523 K. The lack of contraction twinning was explained by the expected decrease in the critical resolved shear stress values for pyramidal slip, and the improved {ɛ} _{ {f}} values at elevated temperatures were attributed to the vanishing activity of contraction twinning.

A PCT-wide collaborative clinical audit selecting recall intervals for patients according to risk.

Science.gov (United States)

Cannell, P J

2011-03-26

This audit was carried out to assess the level to which recall intervals were individually and appropriately selected for patients attending dental practices across a primary care trust (PCT) area in Essex. A retrospective audit was carried out by reference to patient records to assess various criteria, including whether patients were categorised according to risk of oral disease, whether an appropriate recall had been selected and whether a discussion regarding a recall interval had been undertaken. An educational event highlighting the issue of recall intervals was held. Subsequent to this a prospective audit was undertaken to assess relevant criteria. Prospective audit data showed a marked increase in the use of patient risk assessments for caries, periodontal disease, oral cancer and non-carious tooth surface loss (NCTSL). Recall intervals were also more often selected based on a patient's risk status and discussed with the patient compared to that observed in the retrospective audit data. This audit was successful as a tool to bring about change in the behaviour of dentists regarding their determination of appropriate recall intervals for patients. Whether that change in behaviour is long-term or transient requires further investigation.

Final Report - IHLW PCT, Spinel T1%, Electrical Conductivity, and Viscosity Model Development, VSL-07R1240-4

Energy Technology Data Exchange (ETDEWEB)

Kruger, Albert A.; Piepel, Gregory F.; Landmesser, S. M.; Pegg, I. L.; Heredia-Langner, Alejandro; Cooley, Scott K.; Gan, H.; Kot, W. K.

2013-11-13

This report is the last in a series of currently scheduled reports that presents the results from the High Level Waste (HLW) glass formulation development and testing work performed at the Vitreous State Laboratory (VSL) of the Catholic University of America (CUA) and the development of IHLW property-composition models performed jointly by Pacific Northwest National Laboratory (PNNL) and VSL for the River Protection Project-Waste Treatment and Immobilization Plant (RPP-WTP). Specifically, this report presents results of glass testing at VSL and model development at PNNL for Product Consistency Test (PCT), one-percent crystal fraction temperature (T1%), electrical conductivity (EC), and viscosity of HLW glasses. The models presented in this report may be augmented and additional validation work performed during any future immobilized HLW (IHLW) model development work. Completion of the test objectives is addressed.

Corrosion and Mechanical Properties of Al-5 At. Pct Cr Produced by Cryomilling and Subsequent Consolidation at Various Temperatures

Science.gov (United States)

Esquivel, J.; Darling, K. A.; Murdoch, H. A.; Gupta, R. K.

2018-04-01

An Al-5 at. pct Cr alloy was produced by high-energy ball milling at liquid nitrogen temperature followed by consolidation using equal-channel axial extrusion at 200 °C, 300 °C and 450 °C. The microstructure and corrosion response were compared with a cast alloy of the same composition. Rather than the intermetallics expected by the phase diagram and seen in the cast alloy, consolidated HEBM alloys exhibited extended solid solubility of Cr in the aluminum matrix in addition to a finely dispersed Cr-rich phase. This led to improvement in the corrosion behavior as investigated via potentiodynamic polarization and constant immersion tests in NaCl solution. Hardness and tensile tests were performed to evaluate the mechanical properties. The highest consolidation temperature (450 °C) contributed to significant grain growth and Cr diffusion, lessening the beneficial effects of processing with HEBM.

The Value of PCT, WBC and hs-CRP Tests in the Diagnosis and Prognosis of Children with Pneumonia%小儿肺炎中PCT、WBC、hs-CRP检测对疾病诊断及预后判断价值分析

Institute of Scientific and Technical Information of China (English)

夏兰兰; 李敬

2017-01-01

目的 分析小儿肺炎中PCT、WBC、hs-CRP检测对疾病诊断及预后的判断价值.方法 选取2015年5月至2016年4月在本院住院治疗的肺炎患儿120例作为观察组,健康儿童65例作为对照组.检测治疗前后患儿及健康儿童血清PCT、WBC、hs-CRP的变化.结果 治疗前,细菌感染组WBC数量(15.5±3.4)×109/L、hs-CRP水平(19.8±2.6) mg/L和PCT水平(21.9±2.1)ng/mL均明显高于非细菌感染组(6.8 ±2.3)×109/L、(4.5±2.3)mg/L、(4.7±1.8) ng/mL和健康对照组(8.1 ±1.4)×109/L、(3.5±1.2) mg/L、(1.8±0.5) ng/mL,且差异具有统计学意义(P＜0.05).而非细菌感染组和健康对照组的WBC、hs-CRP和PCT结果差异无统计学意义(P＞0.05);治疗后,细菌感染组WBC数量(7.3±1.4)×109/L、hs-CRP水平(5.1 ± 1.2) mg/L和PCT水平(2.3 ± 1.2) ng/mL均明显低于治疗前,差异具有统计学意义(P＜0.05);WBC、hs-CRP、PCT联合检测的灵敏性95.2％、特异性93.0％、准确度93.3％显著高于WBC、hs-CRP、PCT单独检测,差异具有统计学意义(P＜0.05).结论 在小儿肺炎治疗过程中,动态监测患儿血清的WBC、hs-CRP、PCT的变化,并结合临床,有助于诊疗和判断患儿疾病愈后的情况,具有显著的临床意义,值得推广应用.%Objective To estimate the value of PCT,WBC and hs-CRP tests in the diagnosis and prognosis of children with pneumonia.Methods 120 cases with pneumonia in children were selected from May 2015 to April 2016 in our hospital as the observation group,65 cases of healthy children as the control group.Changes of serum PCT,WBC and hs-CRP tests in children and healthy children before and after treatment were mearued.Results Before treatment,bacterial infection group have WBC count (15.5 ± 3.4) × 109/L,hs-CRP levels (19.8±2.6) mg/L and PCT level (21.9 ±2.1) ng/mL,which were significantly higher than those in non bacterial infection group (6.8 ±2.3) × 109/L,(4.5 ±2.3) mg/L,(4.7 ± 1.8) ng/mL and healthy control group (+ 8.1 �

Microstructure and Interfacial Reactions During Vacuum Brazing of Stainless Steel to Titanium Using Ag-28 pct Cu Alloy

Science.gov (United States)

Laik, A.; Shirzadi, A. A.; Sharma, G.; Tewari, R.; Jayakumar, T.; Dey, G. K.

2015-02-01

Microstructural evolution and interfacial reactions during vacuum brazing of grade-2 Ti and 304L-type stainless steel (SS) using eutectic alloy Ag-28 wt pct Cu were investigated. A thin Ni-depleted zone of -Fe(Cr, Ni) solid solution formed on the SS-side of the braze zone (BZ). Cu from the braze alloy, in combination with the dissolved Fe and Ti from the base materials, formed a layer of ternary compound , adjacent to Ti in the BZ. In addition, four binary intermetallic compounds, CuTi, CuTi, CuTi and CuTi formed as parallel contiguous layers in the BZ. The unreacted Ag solidified as islands within the layers of CuTi and CuTi. Formation of an amorphous phase at certain locations in the BZ could be revealed. The -Ti(Cu) layer, formed due to diffusion of Cu into Ti-based material, transformed to an -Ti + CuTi eutectoid with lamellar morphology. Tensile test showed that the brazed joints had strength of 112 MPa and failed at the BZ. The possible sequence of events that led to the final microstructure and the mode of failure of these joints were delineated.

PCT Uncertainty Analysis Using Unscented Transform with Random Orthogonal Matrix

Energy Technology Data Exchange (ETDEWEB)

Fynana, Douglas A.; Ahn, Kwang-Il [KAERI, Daejeon (Korea, Republic of); Lee, John C. [Univ. of Michigan, Michigan (United States)

2015-05-15

Most Best Estimate Plus Uncertainty (BEPU) methods employ nonparametric order statistics through Wilks' formula to quantify uncertainties of best estimate simulations of nuclear power plant (NPP) transients. 95%/95% limits, the 95''t{sup h} percentile at a 95% confidence level, are obtained by randomly sampling all uncertainty contributors through conventional Monte Carlo (MC). Advantages are simple implementation of MC sampling of input probability density functions (pdfs) and limited computational expense of 1''s{sup t}, 2''n{sup d}, and 3''r{sup d} order Wilks' formula requiring only 59, 93, or 124 simulations, respectively. A disadvantage of small sample size is large sample to sample variation of statistical estimators. This paper presents a new efficient sampling based algorithm for accurate estimation of mean and variance of the output parameter pdf. The algorithm combines a deterministic sampling method, the unscented transform (UT), with random sampling through the generation of a random orthogonal matrix (ROM). The UT guarantees the mean, covariance, and 3''r{sup d} order moments of the multivariate input parameter distributions are exactly preserved by the sampled input points and the orthogonal transformation of the points by a ROM guarantees the sample error of all 4''t{sup h} order and higher moments are unbiased. The UT with ROM algorithm is applied to the uncertainty quantification of the peak clad temperature (PCT) during a large break loss-of-coolant accident (LBLOCA) in an OPR1000 NPP to demonstrate the applicability of the new algorithm to BEPU. This paper presented a new algorithm combining the UT with ROM for efficient multivariate parameter sampling that ensures sample input covariance and 3''r{sup d} order moments are exactly preserved and 4''th moment errors are small and unbiased. The advantageous sample properties guarantee higher order accuracy and

Effect of Repair Welding on Electrochemical Corrosion and Stress Corrosion Cracking Behavior of TIG Welded AA2219 Aluminum Alloy in 3.5 Wt Pct NaCl Solution

Science.gov (United States)

Venugopal, A.; Sreekumar, K.; Raja, V. S.

2010-12-01

The stress corrosion cracking (SCC) behavior of AA2219 aluminum alloy in the as-welded (AW) and repair-welded (RW) conditions was examined and compared with that of the base metal (BM) in 3.5 wt pct NaCl solution using the slow strain rate technique (SSRT). The reduction in ductility was used as a parameter to evaluate the SCC susceptibility of both BM and welded joints. The results show that the ductility ratio ( ɛ NaCl/( ɛ air)) of the BM was close to one (0.97) and reduced to 0.9 for the AW joint. This value further reduced to 0.77 after carrying out one repair welding operation. However, the RW specimen exhibited higher ductility than the single-weld specimens even in 3.5 wt pct NaCl solution. SSRT results obtained using pre-exposed samples followed by post-test metallographic observations clearly showed localized pitting corrosion along the partially melted zone (PMZ), signifying that the reduction in ductility ratio of both the AW and RW joints was more due to mechanical overload failure, caused by the localized corrosion and a consequent reduction in specimen thickness, than due to SCC. Also, the RW joint exhibited higher ductility than the AW joint both in air and the environment, although SCC index (SI) for the former is lower than that of the latter. Fractographic examination of the failed samples, in general, revealed a typical ductile cracking morphology for all the base and welded joints, indicating the good environmental cracking resistance of this alloy. Microstructural examination and polarization tests further demonstrate grain boundary melting along the PMZ, and that provided the necessary electrochemical condition for the preferential cracking on that zone of the weldment.

Comparison of PCT, CRP, D-Dimer, Lactate, TNF-α, IL-1β, IL-6 and lL-10 in Development of Systemic Inflammatory Response Syndrome and Sepsis on Patients with Isolated Head Trauma and Polytrauma

Directory of Open Access Journals (Sweden)

Emine Dağlı

2012-12-01

Full Text Available Objective: In this study, it was aimed to compare the relationship between Glasgow Coma Scale (GKS, ISS values, PCT, CRP, D-Dimer, laktat, TNF-α, IL-1β, IL-6, IL-10 in patients with polytrauma and isolated head trauma in conjunction with SIRS and sepsis. Material and Method: Total of 68 patients (32 polytrauma, 36 isolated head trauma aged between 18-65 years were enrolled in the study. For 7 days of follow up, the biochemical parameters were analysed on the days 0, 1, 3, 5, 7 and the ISS, GCS score and growth rates of SIRS and sepsis were recorded. Results: It was demonstrated that for patients with isolated head trauma, SIRS (80.6%, sepsis (38.9% and mortality values (71.4% were higher and there is a statistically important linear and inverse relationship between ISS and GCS values (p<0.05. During sepsis and SIRS phases, CRP elevated in both groups, whereas PCT only in the polytrauma group. D-Dimer values were investigated high in both groups, but atypically decreased on day 3 in isolated head trauma group. Lactate, TNF-α and, IL-1β were within reference values, IL-6 and IL-10 values were elevated in both groups but were higher in the polytrauma group. Conclusion: Although multiple variations were detected in serum markers of pro-inflamatory and acute phase proteins, we thought that these are inadequate in predicting mortality and complications such as SIRS and sepsis.

Interpretations of referral appropriateness by senior health managers in five PCT areas in England: a qualitative investigation.

Science.gov (United States)

Blundell, N; Clarke, Aileen; Mays, N

2010-06-01

To explore interpretations of "appropriate" and "inappropriate" elective referral from primary to secondary surgical care among senior clinical and non-clinical managers in five purposively sampled primary care trusts (PCTs) and their main associated acute hospitals in the English National Health Service (NHS). Semi-structured face-to-face interviews were undertaken with senior managerial staff from clinical and non-clinical backgrounds. Interviews were tape-recorded, transcribed and analysed according to the Framework approach developed at the National Centre for Social Research using N6 (NUD*IST6) qualitative data analysis software. Twenty-two people of 23 approached were interviewed (between three and five respondents per PCT and associated acute hospital). Three attributes relating to appropriateness of referral were identified: necessity: whether a patient with given characteristics was believed suitable for referral; destination or level: where or to whom a patient should be referred; and quality (or process): how a referral was carried out, including (eg, investigations undertaken before referral, information contained in the referral and extent of patient involvement in the referral decision. Attributes were hierarchical. "Necessity" was viewed as the most fundamental attribute, followed by "destination" and, finally, "quality". In general, but not always, all three attributes were perceived as necessary for a referral to be defined as appropriate. For senior clinical and non-clinical managers at the local level in the English NHS, three hierarchical attributes (necessity, appropriateness of destination and quality of referral process) contributed to the overall concept of appropriateness of referral from primary to secondary surgical care.

76 FR 76951 - Submission for OMB Review; Comment Request

Science.gov (United States)

2011-12-09

... Office (USPTO). Title: Patent Prosecution Highway (PPH) Program. Form Number(s): PTO/SB/20AT/AU/BR/CA/CN/DE/DK, PTO/SB/20EP/ES/FI/ HU/IL/IS/JP/KR/MX/NO/RU/SG/TW/UK, and PTO/SB/20PCT-AT/PCT-AU/PCT-CA/ PCT-CN/PCT-EP/PCT-ES/PCT-FI/PCT-JP/PCT-KR/PCT-NPI/PCT-RU/PCT-SE/PCT-US. Agency Approval Number: 0651-0058...

Role of Procalcitonin in Differentiating between Infectious and Noninfectious Fevers among Patients with Lymphoma.

Science.gov (United States)

Wang, Xiao Jun; Tan, Thuan Tong; Lim, Soon Thye; Farid, Mohamad; Tao, Miriam; Quek, Richard; Chan, Alexandre; Tang, Tiffany

2017-08-01

The primary objective of this study is to prospectively evaluate the role of procalcitonin (PCT) in distinguishing infectious fever from noninfectious fever (NIF) among febrile lymphoma patients. The secondary objective is to evaluate the usefulness of PCT in distinguishing among bloodstream infections (BSI), local infections and unidentified infections (LIUI), and NIF. Patients with lymphoma and fever were prospectively recruited between August 2014 and November 2015. PCT was measured within 24 hours of fever onset (PCT1) and 24-72 hours thereafter (PCT2). The higher PCT value between PCT1 and PCT2 was also documented (PCT max ). PCT levels (PCT1, PCT2, and PCT max ) were compared for BSI, LIUI, and NIF. In addition, the difference between PCT1 and PCT2 was evaluated in patients with complete data on both PCT1 and PCT2. Of 108 eligible patients, 12 were diagnosed with BSI, 83 with LIUI, and 13 with NIF. PCT max was statistically different between the infectious fever (BSI and LIUI combined) and NIF groups (median PCT max : 0.44 ng/ml vs 0.19 ng/ml; p=0.026). PCT1 was not statistically different for patients with BSI, LIUI, and NIF (p=0.217). However, PCT2 and PCT max were significantly higher in patients with BSI compared to those with NIF (p=0.026 and 0.002, respectively). Meanwhile, patients with BSI have significantly higher PCT max values than those with LIUI (p=0.034). Among 90 cases with complete data on both PCT1 and PCT2, PCT2 was significantly higher than PCT1 in patients with BSI (median PCT: 0.98 ng/ml vs 0.47 ng/ml; p=0.045) and patients with LIUI (median PCT: 0.43 ng/ml vs 0.24 ng/ml; p=0.004), while not significant in patients with NIF (p=0.374). Two separate PCT measurements can differentiate between infectious fever and NIF and predict for BSI in lymphoma patients with fever. © 2017 Pharmacotherapy Publications, Inc.

Removal of radon by aeration testing of various aeration techniques for small water works. For European Commission under Contract No FI4PCT960054 TENAWA project

CERN Document Server

Salonen, L; Mehtonen, J; Mjoenes, L; Raff, O; Turunen, H

2002-01-01

Capability of various aeration techniques to remove radon from water in small waterworks was studied as a part of project (Treatment Techniques for Removing Natural Radionuclides from Drinking Water), which was carried out during 1997-1999 on a cost-shared basis (contract No. F14PCT960054) with The European Commission (CEC) under the supervision of the Directorate-General XII Radiation Protection Research Unit. In TENAWA project both laboratory and field experiments were performed in order to find reliable methods and equipment for removing natural radionuclides from ground water originating either from private wells or small waterworks. Because such techniques are more often needed in private households than at waterworks, the main emphasis of the research was aimed to solve the water treatment problems related to the private water supplies, especially bedrock wells. Radon was the most important radionuclide to be removed from water at waterworks whereas the removal of other radionuclides ( sup 2 sup 3 sup 4...

Effect of Continuous Galvanizing Heat Treatments on the Microstructure and Mechanical Properties of High Al-Low Si Transformation Induced Plasticity Steels

Science.gov (United States)

Bellhouse, E. M.; McDermid, J. R.

2010-02-01

Heat treatments were performed using an isothermal bainitic transformation (IBT) temperature compatible with continuous hot-dip galvanizing on two high Al-low Si transformation induced plasticity (TRIP)-assisted steels. Both steels had 0.2 wt pct C and 1.5 wt pct Mn; one had 1.5 wt pct Al and the other had 1 wt pct Al and 0.5 wt pct Si. Two different intercritical annealing (IA) temperatures were used, resulting in intercritical microstructures of 50 pct ferrite (α)-50 pct austenite (γ) and 65 pct α-35 pct γ. Using the IBT temperature of 465 °C, five IBT times were tested: 4, 30, 60, 90, and 120 seconds. Increasing the IBT time resulted in a decrease in the ultimate tensile strength (UTS) and an increase in the uniform elongation, yield strength, and yield point elongation. The uniform elongation was higher when using the 50 pct α-50 pct γ IA temperature when compared to the 65 pct α-35 pct γ IA temperature. The best combinations of strength and ductility and their corresponding heat treatments were as follows: a tensile strength of 895 MPa and uniform elongation of 0.26 for the 1.5 pct Al TRIP steel at the 50 pct γ IA temperature and 90-second IBT time; a tensile strength of 880 MPa and uniform elongation of 0.27 for the 1.5 pct Al TRIP steel at the 50 pct γ IA temperature and 120-second IBT time; and a tensile strength of 1009 MPa and uniform elongation of 0.22 for the 1 pct Al-0.5 pct Si TRIP steel at the 50 pct γ IA temperature and 120-second IBT time.

Thermally Stable Ni-rich Austenite Formed Utilizing Multistep Intercritical Heat Treatment in a Low-Carbon 10 Wt Pct Ni Martensitic Steel

Science.gov (United States)

Jain, Divya; Isheim, Dieter; Zhang, Xian J.; Ghosh, Gautam; Seidman, David N.

2017-08-01

Austenite reversion and its thermal stability attained during the transformation is key to enhanced toughness and blast resistance in transformation-induced-plasticity martensitic steels. We demonstrate that the thermal stability of Ni-stabilized austenite and kinetics of the transformation can be controlled by forming Ni-rich regions in proximity of pre-existing (retained) austenite. Atom probe tomography (APT) in conjunction with thermodynamic and kinetic modeling elucidates the role of Ni-rich regions in enhancing growth kinetics of thermally stable austenite, formed utilizing a multistep intercritical ( Quench- Lamellarization- Tempering (QLT)-type) heat treatment for a low-carbon 10 wt pct Ni steel. Direct evidence of austenite formation is provided by dilatometry, and the volume fraction is quantified by synchrotron X-ray diffraction. The results indicate the growth of nm-thick austenite layers during the second intercritical tempering treatment (T-step) at 863 K (590 °C), with austenite retained from first intercritical treatment (L-step) at 923 K (650 °C) acting as a nucleation template. For the first time, the thermal stability of austenite is quantified with respect to its compositional evolution during the multistep intercritical treatment of these steels. Austenite compositions measured by APT are used in combination with the thermodynamic and kinetic approach formulated by Ghosh and Olson to assess thermal stability and predict the martensite-start temperature. This approach is particularly useful as empirical relations cannot be extrapolated for the highly Ni-enriched austenite investigated in the present study.

CTA-enhanced perfusion CT: an original method to perform ultra-low-dose CTA-enhanced perfusion CT

Energy Technology Data Exchange (ETDEWEB)

Tong, Elizabeth; Wintermark, Max [University of Virginia, Department of Radiology, Neuroradiology Division, Charlottesville, VA (United States)

2014-11-15

Utilizing CT angiography enhances image quality in PCT, thereby permitting acquisition at ultra-low dose. Dynamic CT acquisitions were obtained at 80 kVp with decreasing tube current-time product [milliamperes x seconds (mAs)] in patients suspected of ischemic stroke, with concurrent CTA of the cervical and intracranial arteries. By utilizing fast Fourier transformation, high spatial frequencies of CTA were combined with low spatial frequencies of PCT to create a virtual PCT dataset. The real and virtual PCT datasets with decreasing mAs were compared by assessing contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and noise and PCT values and by visual inspection of PCT parametric maps. Virtual PCT attained CNR and SNR three- to sevenfold superior to real PCT and noise reduction by a factor of 4-6 (p < 0.05). At 20 mAs, virtual PCT achieved diagnostic parametric maps, while the quality of real PCT maps was inadequate. At 10 mAs, both real and virtual PCT maps were nondiagnostic. Virtual PCT (but not real PCT) maps regained diagnostic quality at 10 mAs by applying 40 % adaptive statistical iterative reconstruction (ASIR) and improved further with 80 % ASIR. Our new method of creating virtual PCT by combining ultra-low-dose PCT with CTA information yields diagnostic perfusion parametric maps from PCT acquired at 20 or 10 mAs with 80 % ASIR. Effective dose is approximately 0.20 mSv, equivalent to two chest radiographs. (orig.)

Risbjerg: SF vandt valgkampen, NA og R tabte

DEFF Research Database (Denmark)

Thomsen, Søren Risbjerg

2007-01-01

ANALYSE: Endnu engang flyttede en valgkamp for alvor stemmer. SF gik undervejs 27 pct. frem, mens NA gik 34 pct. tilbage og R 26 pct. Udgivelsesdato: 25. november......ANALYSE: Endnu engang flyttede en valgkamp for alvor stemmer. SF gik undervejs 27 pct. frem, mens NA gik 34 pct. tilbage og R 26 pct. Udgivelsesdato: 25. november...

Colon-targeted delivery of piceatannol enhances anti-colitic effects of the natural product: potential molecular mechanisms for therapeutic enhancement

Directory of Open Access Journals (Sweden)

Yum S

2015-08-01

Full Text Available Soohwan Yum, Seongkeun Jeong, Sunyoung Lee, Joon Nam, Wooseong Kim, Jin-Wook Yoo, Min-Soo Kim, Bok Luel Lee, Yunjin Jung College of Pharmacy, Pusan National University, Busan, Republic of Korea Abstract: Piceatannol (PCT, an anti-colitic natural product, undergoes extensive Phase II hepatic metabolism, resulting in very low bioavailability. We investigated whether colon-targeted delivery of PCT could enhance anti-colitic effects and how therapeutic enhancement occurred at the molecular level. Molecular effects of PCT were examined in human colon carcinoma cells and inflamed colons. The anti-colitic effects of PCT in a colon-targeted capsule (colon-targeted PCT were compared with PCT in a gelatin capsule (conventional PCT in a trinitrobenzene sulfonic acid-induced rat colitis model. Colon-targeted PCT elicited greatly enhanced recovery of the colonic inflammation. In HCT116 cells, PCT inhibited nuclear factor kappaB while activating anti-colitic transcription factors, nuclear factor-erythroid 2 (NF-E2 p45-related factor 2, and hypoxia-inducible factor-1. Colon-targeted PCT, but not conventional PCT, modulated production of the target gene products of the transcription factors in the inflamed colonic tissues. Rectal administration of PCT, which simulates the therapeutic action of colon-targeted PCT, also ameliorated rat colitis and reproduced the molecular effects in the inflamed colonic tissues. Colon-targeted delivery increased therapeutic efficacy of PCT against colitis, likely resulting from multitargeted effects exerted by colon-targeted PCT. The drug delivery technique may be useful for therapeutic optimization of anti-colitic lead compounds including natural products. Keywords: piceatannol, colitis, colon-targeted delivery, multitarget, polypharmacology

United States Air Force Statistical Digest, Fiscal Year 1975. 13th Edition

Science.gov (United States)

1976-04-15

Rubber . 1,290...INDIt.N NBR PCT OF IE tlTAl NBR FeT TOTAL KIN Na~ PCl WOH~N (,.(A(,E, TCT p~O"I •. _. NBto’ PCT t.. wo... MI’~ F 181 8.5" T U1 10.38 35 1.70 ’H 3.25 (,5-;:1...NEGRO SP~~-SUR’IA"’E I "OIA~ ORIENTAL TOTAL HIN 1I0HEN ~RAOE, TOT p~ O~:/:’ C ’ GUlj)E LE~EL Nd~ FeT NS~ PCT NBR PCT NeR PCT NBR PCT NBR PCT l WO,~ 𔃻

Carboxymethyl inulin

NARCIS (Netherlands)

Van Brussel, D.L.; Batelaan, J.G,; Peters, A.; Van Bekkum, H.

1995-01-01

Abstract of corresponding document: US 5777090 (A) PCT No. PCT/EP94/04097 Sec. 371 Date Jun. 6, 1996 Sec. 102(e) Date Jun. 6, 1996 PCT Filed Dec. 9, 1994 PCT Pub. No. WO95/15984 PCT Pub. Date Jun. 15, 1995Disclosed is carboxymethyl inulin having a degree of substitution (DS) ranging from 0,15 to

Antibiotic treatment interruption of suspected lower respiratory tract infections based on a single procalcitonin measurement at hospital admission--a randomized trial

DEFF Research Database (Denmark)

Kristoffersen, K B; Søgaard, O S; Wejse, C

2009-01-01

Recent studies have suggested that procalcitonin (PCT) is a safe marker for the discrimination between bacterial and viral infection, and that PCT-guided treatment may lead to substantial reductions in antibiotic use. The present objective was to evaluate the effect of a single PCT measurement...... to either PCT-guided treatment or standard treatment. Antibiotic treatment duration in the PCT group was based on the serum PCT value at admission. The cut-off point for recommending antibiotic treatment was PCT > or =0.25 microg/L. Physicians could overrule treatment guidelines. The mean duration...... of hospital stay was 5.9 days in the PCT group vs. 6.7 days in the control group (p 0.22). The mean duration of antibiotic treatment during hospitalization in the PCT group was 5.1 days on average, as compared to 6.8 days in the control group (p 0.007). In a subgroup analysis of chronic obstructive pulmonary...

Elevated Temperature Effects on the Plastic Anisotropy of an Extruded Mg-4 Wt Pct Li Alloy: Experiments and Polycrystal Modeling

Science.gov (United States)

Risse, Marcel; Lentz, Martin; Fahrenson, Christoph; Reimers, Walter; Knezevic, Marko; Beyerlein, Irene J.

2017-01-01

In this work, we study the deformation behavior of Mg-4 wt pct Li in uniaxial tension as a function of temperature and loading direction. Standard tensile tests were performed at temperatures in the range of 293 K (20 °C) ≤ T ≤ 473 K (200 °C) and in two in-plane directions: the extrusion and the transverse. We find that while the in-plane plastic anisotropy (PA) decreases with temperature, the anisotropy in failure strain and texture development increases. To uncover the temperature dependence in the critical stresses for slip and in the amounts of slip and twinning systems mediating deformation, we employ the elastic-plastic self-consistent polycrystal plasticity model with a thermally activated dislocation density based hardening law for activating slip with individual crystals. We demonstrate that the model, with a single set of intrinsic material parameters, achieves good agreement with the stress-strain curves, deformation textures, and intragranular misorientation axis analysis for all test directions and temperatures. With the model, we show that at all temperatures the in-plane tensile behavior is driven primarily by analysis explains that the in-plane PA decreases and failure strains increase with temperature as a result of a significant reduction in the activation stress for pyramidal multiple types of < a rangle and < {c + a} rangle slip. The results also show that because of the strong initial texture, in-plane texture development is anisotropic since prismatic slip dominates the deformation in one test, although it is not the easiest slip mode, and basal slip in the other. These findings reveal the relationship between the temperature-sensitive thresholds needed to activate crystallographic slip and the development of texture and macroscopic PA.

Stress Corrosion Cracking Behavior of Multipass TIG-Welded AA2219 Aluminum Alloy in 3.5 wt pct NaCl Solution

Science.gov (United States)

Venugopal, A.; Sreekumar, K.; Raja, V. S.

2012-09-01

The stress corrosion cracking (SCC) behavior of the AA2219 aluminum alloy in the single-pass (SP) and multipass (MP) welded conditions was examined and compared with that of the base metal (BM) in 3.5 wt pct NaCl solution using a slow-strain-rate technique (SSRT). The reduction in ductility was used as a parameter to evaluate the SCC susceptibility of both the BM and welded joints. The results showed that the ductility ratio ( ɛ NaCl/( ɛ air) was 0.97 and 0.96, respectively, for the BM and MP welded joint, and the same was marginally reduced to 0.9 for the SP welded joint. The fractographic examination of the failed samples revealed a typical ductile cracking morphology for all the base and welded joints, indicating the good environmental cracking resistance of this alloy under all welded conditions. To understand the decrease in the ductility of the SP welded joint, preexposure SSRT followed by microstructural observations were made, which showed that the decrease in ductility ratio of the SP welded joint was caused by the electrochemical pitting that assisted the nucleation of cracks in the form of corrosion induced mechanical cracking rather than true SCC failure of the alloy. The microstructural examination and polarization tests demonstrated a clear grain boundary (GB) sensitization of the PMZ, resulting in severe galvanic corrosion of the SP weld joint, which initiated the necessary conditions for the localized corrosion and cracking along the PMZ. The absence of PMZ and a refined fusion zone (FZ) structure because of the lesser heat input and postweld heating effect improved the galvanic corrosion resistance of the MP welded joint greatly, and thus, failure occurred along the FZ.

Procalcitonin and albumin as prognostic biomarkers in elderly patients with a risk of bacterial infection.

Science.gov (United States)

Higashikawa, Toshihiro; Okuro, Masashi; Ishigami, Keiichirou; Mae, Kunihiro; Sangen, Ryusho; Mizuno, Takurou; Usuda, Daisuke; Saito, Atushi; Kasamaki, Yuji; Fukuda, Akihiro; Saito, Hitoshi; Morimoto, Shigeto; Kanda, Tsugiyasu

2018-01-01

Aim This study was performed to investigate serum procalcitonin (PCT) and albumin (Alb) as prognostic biomarkers in elderly patients at risk of bacterial infection. Methods Serum PCT was measured in 270 hospitalized patients (mean age, 77.4 years) with suspected bacterial infection. The PCT-negative (2.5 g/dL), no significant difference in survival was observed between the PCT-positive and -negative groups. However, within the Alb-negative group (≤2.5 g/dL), the survival rate was significantly lower in the PCT-positive than -negative group. PCT was strongly associated with CRP and Alb, and having both PCT positivity and Alb negativity was a prognostic factor for elderly people at risk of bacterial infection. Conclusions Combined measurement of PCT with Alb is expected to be a valuable tool to assess prognosis in elderly people at risk of bacterial infection.

Strength of initially virgin martensites at - 196 °C after aging and tempering

Science.gov (United States)

Eldis, George T.; Cohen, Morris

1983-06-01

The compressive strength at -196°C of martensites in Fe-0.26 pct C-24 pct Ni, Fe-0.4 pct C-21 pct Ni, and Fe-0.4 pct C-18 pct Ni-3 pct Mo alloys, all with subzero M temperatures, has been determined in the virgin condition and after one hour at temperatures from -80 to +400 °C. The effects of ausforming (20 pct reduction in area of the austenite by swaging at room temperature prior to the martensitic transformation) were also investigated. For the unausformed martensites, aging at temperatures up to 0 °C results in relatively small increases in strength. Above 0 °C, the age hardening increment increases rapidly, reaching a maximum at 100 °C. Above 100 °C, the strength decreases continuously with increasing tempering temperature except for the molybdenum-containing alloy, which exhibits secondary hardening on tempering at 400 °C. For the ausformed martensites, the response to aging at subzero temperatures is greater than for unausformed material. Strength again passes through a maximum on aging at 100 °C. However, on tempering just above 100 °C, the ausformed materials show a slower rate of softening than the unausformed martensites. The strengthening produced by the ausforming treatment is largest for the Fe-0.4 pct C-18 pct Ni-3 pct Mo alloy, but there is no evidence of carbide precipitation in the deformed austenite to a°Count for this effect of molybdenum.

The role of elevated serum procalcitonin in neuroendocrine neoplasms of digestive system.

Science.gov (United States)

Chen, Luohai; Zhang, Yu; Lin, Yuan; Deng, Langhui; Feng, Shiting; Chen, Minhu; Chen, Jie

2017-12-01

Elevated serum procalcitonin (PCT) was reported in patients with certain type of neuroendocrine neoplasms (NENs). The aim of this study was to assess the role of elevated serum PCT in NENs from digestive system. Serum PCT and serum CgA level were measured in 155 patients with NENs from digestive system. Elevated serum PCT was found in 63 patients (40.6%). Grade 3 disease was a significant factor associated with elevated serum PCT (OR, 9.24; 95%CI, 3.04-28.08; Pdigestive system, especially in patients with grade 3 disease. Serum PCT level can help evaluate treatment response and its elevation indicates poor prognosis. Combination of serum PCT and CgA can improve outcome prediction. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Effect of Heat Treatment on Morphology of Fe-Rich Intermetallics in Hypereutectic Al-Si-Cu-Ni Alloy with 1.26 pct Fe

Science.gov (United States)

Sha, Meng; Wu, Shusen; Wan, Li; Lü, Shulin

2013-12-01

Cobalt is generally considered as the element that can neutralize the negative effects of iron in Al alloys, such as inducing fracture and failure for stress concentration. Nevertheless, Fe-rich intermetallics would be inclined to form coarse plate-like δ-Al4(Fe, Co, Ni)Si2 particles when the content of Fe was high, which could also cause inferior mechanical properties. The dissolution and transformation of δ-Al4(Fe, Co, Ni)Si2 phase in solution heat-treated samples of Al-20Si-1.85Cu-1.05Ni-1.26Fe-1.35Co alloy were studied using optical microscopy, image analysis, and scanning electron microscopy. The effects of solution heat treatment time ranging from 0 to 9 hours at 783.15 K (510 °C) on mechanical properties were also investigated. The coarse plate-like δ-Al4(Fe, Co, Ni)Si2 particles varied slowly through concurrent dissolution along widths and at the plate tips as solution treatment time increased, which could be explained from diffusion-induced grain boundary migration. Solution heat treatment also has an important influence on mechanical properties. The maximum ultimate tensile strength and yield strength after T6 treatment were 258 and 132 MPa, respectively, while the maximum hardness was 131 HB. Compared with those of the samples in the as-cast state, they increased by 53, 42, and 28 pct, respectively. Moreover, δ-Al4(Fe, Co, Ni)Si2 phase, which appears as a coarse plate-like particle in two dimensions, is actually a cuboid in three dimensions. The length of this cuboid is close to the width, while the height is much smaller.

Innervation of the renal proximal convoluted tubule of the rat

International Nuclear Information System (INIS)

Barajas, L.; Powers, K.

1989-01-01

Experimental data suggest the proximal tubule as a major site of neurogenic influence on tubular function. The functional and anatomical axial heterogeneity of the proximal tubule prompted this study of the distribution of innervation sites along the early, mid, and late proximal convoluted tubule (PCT) of the rat. Serial section autoradiograms, with tritiated norepinephrine serving as a marker for monoaminergic nerves, were used in this study. Freehand clay models and graphic reconstructions of proximal tubules permitted a rough estimation of the location of the innervation sites along the PCT. In the subcapsular nephrons, the early PCT (first third) was devoid of innervation sites with most of the innervation occurring in the mid (middle third) and in the late (last third) PCT. Innervation sites were found in the early PCT in nephrons located deeper in the cortex. In juxtamedullary nephrons, innervation sites could be observed on the PCT as it left the glomerulus. This gradient of PCT innervation can be explained by the different tubulovascular relationships of nephrons at different levels of the cortex. The absence of innervation sites in the early PCT of subcapsular nephrons suggests that any influence of the renal nerves on the early PCT might be due to an effect of neurotransmitter released from renal nerves reaching the early PCT via the interstitium and/or capillaries

Effects of the Cr2O3 Content on the Viscosity of CaO-SiO2-10 Pct Al2O3-Cr2O3 Quaternary Slag

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Wu, Tuo; Zhang, Yanling; Yuan, Fang; An, Zhuoqing

2018-04-01

The present study experimentally investigates the effect of Cr2O3 on the viscosity of molten slags. The viscosities of CaO-SiO2-10 pct Al2O3-Cr2O3 quaternary slags with two different binary basicities (R, basic slag with R = 1.2 and acidic slag with R = 0.8) were measured by the rotating cylindrical method from 1813 K to 1953 K (1540 °C to 1680 °C). The results showed that the viscosity of both types of slag decreased as the Cr2O3 content increased, but the viscosity of acidic slags exhibited a greater decrease. The slags showed good Newtonian behavior at such high temperatures. Cr2O3 could act as a network modifier to simplify the Si-O-Si tetrahedral structure, as verified by the Raman spectral analysis, which was consistent with the decreasing trend of viscosity. The activation energy of viscous flow decreased slightly with increasing Cr2O3, but increasing the basicity seemed to be more effective in decreasing the viscosity than adding Cr2O3.

Accuracy of the detection of infratentorial stroke lesions using perfusion CT: an experimenter-blinded study

International Nuclear Information System (INIS)

Lee, In Hyouk; Kim, Myung Soon; Kim, Young Ju; Lee, Myeong Sub; You, Joshua H.; Lee, Ji Yong; Whang, Kum

2010-01-01

Although perfusion CT (PCT) for the detection of supratentorial stroke is well established, there is a dearth of evidence of its effectiveness in the detection of infratentorial stroke. Hence, this study compared sensitivity, specificity, and accuracy of PCT maps between infratentorial and supratentorial stroke lesions. One hundred patients with acute stroke who had successfully undergone near whole-brain PCT with the toggling table technique and follow-up MRI were included. Wilcoxon Mann-Whitney test was performed at P 0.01 in all PCT maps) between supratentorial and infratentorial stroke. Also, there was no remarkable difference in both sensitivity and specificity of PCT maps. This was the first study to investigate the accuracy of PCT with the toggling table technique in detection of infratentorial stroke lesions. Clinically, PCT is highly reliable and accurate in detecting infratentorial stroke lesions. (orig.)

Wear Behavior of Plasma Spray Deposited and Post Heat-Treated Hydroxyapatite (HA)-Based Composite Coating on Titanium Alloy (Ti-6Al-4V) Substrate

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Kumari, Renu; Majumdar, Jyotsna Dutta

2018-04-01

The present study concerns a detailed evaluation of wear resistance property of plasma spray deposited composite hydroxyapatite (HA)-based (HA-50 wt pct TiO2 and HA-10 wt pct ZrO2) bioactive coatings developed on Ti-6Al-4V substrate and studying the effect of heat treatment on it. Heat treatment of plasma spray deposited samples has been carried out at 650 °C for 2 hours (for HA-50 wt pct TiO2 coating) and at 750 °C for 2 hours (for HA-10 wt pct ZrO2 coating). There is significant deterioration in wear resistance for HA-50 wt pctTiO2 coating and a marginal deterioration in wear resistance for HA-10 wt pct ZrO2 coating in as-sprayed state (as compared to as-received Ti-6Al-4V) which is, however, improved after heat treatment. The coefficient of friction is marginally increased for both HA-50 wt pct TiO2 and HA-10 wt pct ZrO2 coatings in as-sprayed condition as compared to Ti-6Al-4V substrate. However, coefficient of friction is decreased for both HA-50 wt pct TiO2 and HA-10 wt pct ZrO2 coatings after heat-treated condition as compared to Ti-6Al-4V substrate. The maximum improvement in wear resistance property is, however, observed for HA-10 wt pct ZrO2 sample after heat treatment. The mechanism of wear has been investigated.

PROCALCITONIN TESTING IN RHEUMATOLOGY

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D. V. Bukhanova

2017-01-01

Full Text Available Currently, differential diagnosis of systemic bacterial infection and active rheumatic process remains a challenging problem in rheumatology. In the review, current data on the role of procalcitonin biomarker in diagnosis and differential diagnosis of rheumatic diseases (RD and infectious pathology are presented. In particular, some authors recommend procalcitonin (PCT test as a marker of bacterial infection in bones and joints at levels above 0.5 ng/ml; at PCT level below 0.3 ng/ml, infection can be ruled out. In patients with microcrystalline arthritis, data on the significance of PCT for differential diagnosis are contradictory. PCT level doesn’t correlate with systemic lupus erythematosus activity and is elevated only during bacterial infection proportionally to its systematicity. In some studies, elevated PCT level was observed in ANCA-associated vasculitis with high activity without bacterial infection. It was shown that in 80 % of adults with Still’s disease, PCT level was higher than the threshold value even without infection. For patients with RD hospitalized in intensive care units, PCT clearance is a more informative predictive characteristic than its level, regardless of the cause of PCT elevation (infection, injury, severe organ damage, etc.; slowdown of its decrease is a factor of poor prognosis and is associated with higher mortality. At the same time, PCT level positively correlates with the SOFA score in presence of bacterial infection. For some rheumatic diseases, the threshold PCT value at which the test has optimal sensitivity and specificity is yet to be established. Nonetheless, PCT should be evaluated in relation to the clinical picture and data of additional examinations. The effect of various therapy methods used in rheumatology on PCT level requires further research.

Perfusion CT compared to H{sub 2}{sup 15}O/O{sup 15}O PET in patients with chronic cervical carotid artery occlusion

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Kamath, Amita; Chien, Jeffrey D.; Dillon, William P.; Wintermark, Max [University of California, San Francisco, Department of Radiology, Neuroradiology Section, San Francisco, CA (United States); Smith, Wade S. [University of California, Department of Neurology, San Francisco, CA (United States); Powers, William J. [University of North Carolina, Department of Neurology, Chapel Hill, NC (United States); Cianfoni, Alessandro [Catholic University of Sacred Heart, Department of Bioimages and Radiological Sciences, Rome (Italy); Videen, Tom [Washington University School of Medicine, Departments of Neurology and Radiology, St. Louis, MO (United States); Lawton, Michael T. [University of California, San Francisco, CA (United States). Department of Neurosurgery; Finley, Bruce [Northern California PET Imaging Center, Sacramento, CA (United States)

2008-09-15

The purpose of this study was to compare the results of perfusion computed tomography (PCT) with those of {sup 15}O{sub 2}/H{sub 2}{sup 15}O positron emission tomography (PET) in a subset of Carotid Occlusion Surgery Study (COSS) patients. Six patients enrolled in the COSS underwent a standard-of-care PCT in addition to the {sup 15}O{sub 2}/H{sub 2}{sup 15}O PET study used for selection for extracranial-intracranial bypass surgery. PCT and PET studies were coregistered and then processed separately by different radiologists. Relative measurement of cerebral blood flow (CBF) and oxygen extraction fraction (OEF) were calculated from PET. PCT datasets were processed using different arterial input functions (AIF). Relative PCT and PET CBF values from matching regions of interest were compared using linear regression model to determine the most appropriate arterial input function for PCT. Also, PCT measurements using the most accurate AIF were evaluated for linear regression with respect to relative PET OEF values. The most accurate PCT relative CBF maps with respect to the gold standard PET CBF were obtained when CBF values for each arterial territory are calculated using a dedicated AIF for each territory (R{sup 2}=0.796, p<0.001). PCT mean transit time (MTT) is the parameter that showed the best correlation with the count-based PET OEF ratios (R{sup 2}=0.590, p<0.001). PCT relative CBF compares favorably to PET relative CBF in patients with chronic carotid occlusion when processed using a dedicated AIF for each territory. The PCT MTT parameter correlated best with PET relative OEF. (orig.)

The efficacy of procalcitonin as a biomarker in the management of sepsis: slaying dragons or tilting at windmills?

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Sridharan, Prasanna; Chamberlain, Ronald S

2013-12-01

Sepsis is defined as systemic inflammatory response syndrome (SIRS) in the context of an underlying infectious process, and is associated with high rates of morbidity and mortality, particularly when initial therapy is delayed. Numerous biomarkers, including but not limited to cytokines (interleukins-2 and -6 [IL-2, IL-6] and tumor necrosis factor-α [TNF-α]), leukotrienes, acute-phase proteins (C-reactive protein [CRP]), and adhesion molecules, have been evaluated and rejected as unsuitable for the diagnosis of sepsis, predicting its severity, and guiding its treatment. Most recently, procalcitonin (PCT) has been suggested as a novel biomarker that may be useful in guiding therapeutic decision making in the management of sepsis. This article assesses critically the published literature on the clinical utility of PCT concentrations for guiding the treatment of sepsis in adult patients. A comprehensive search of all published studies of the use of serum concentrations of PCT to guide the treatment of sepsis in adult patients (1996 to 2011) was conducted with PubMed and Google Scholar. The search focused on the value of PCT concentrations to guide the diagnosis, prognosis, monitoring, and escalation and de-escalation of antbiotic therapy in these patients. Keywords searched included "procalcitonin," "sepsis," "sepsis biomarker," "sepsis diagnosis," "sepsis prognosis," "sepsis mortality," "antibiotic escalation," "antibiotic de-escalation," "antibiotic duration," and "antimicrobial stewardship." Forty-six trials evaluating the efficacy of PCT concentrations in diagnosing sepsis have been published, with 39 of these trials yielding positive results and 7 yielding negative results. Wanner et al. published the largest study (n=405) demonstrating that peak PCT concentrations occur early after injury in both patients with sepsis and those with multiple organ dysfunction syndrome (MODS). Among 17 trials assessing the prognostic value of PCT concentrations with regard to

Procalcitonin, MR-Proadrenomedullin, and Cytokines Measurement in Sepsis Diagnosis: Advantages from Test Combination

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Silvia Angeletti

2015-01-01

Full Text Available Background. Elevated cytokines levels correlate with sepsis severity and mortality but their role in the diagnosis is controversial, whereas Procalcitonin (PCT has been largely used. Recently, the mid-regional proadrenomedullin (MR-proADM has been combined with PCT for diagnosis optimization. In this study the combined measurement of PCT, MR-proADM, and cytokines in patients with sepsis was evaluated. Methods. One hundred and four septic patients and 101 controls were enrolled. Receiver operating characteristic (ROC analysis and multiple logistic regression were used to evaluate applicant markers for sepsis diagnosis. Markers with best Odds Ratio (OR were combined, and the posttest probability and a composite score were computed. Results. Based upon ROC curves analysis, PCT, MR-proADM, IL-6, IL-10, TNF-α, and MCP-1 were considered applicant for sepsis diagnosis. Among these PCT, MR-proADM , IL-6, and TNF-α showed the best OR. A better posttest probability was found with the combination of PCT with MR-proADM and PCT with IL-6 or TNF-α compared to the single marker. A composite score of PCT, MR-proADM, and TNF-α showed the best ROC curve in the early diagnosis of sepsis. Conclusion. The combination of PCT with other markers should expedite diagnosis and treatment of sepsis optimizing clinical management.

Procalcitonin as an adjunctive biomarker in sepsis

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Mahua Sinha

2011-01-01

Full Text Available Sepsis can sometimes be difficult to substantiate, and its distinction from non-infectious conditions in critically ill patients is often a challenge. Serum procalcitonin (PCT assay is one of the biomarkers of sepsis. The present study was aimed to assess the usefulness of PCT assay in critically ill patients with suspected sepsis. The study included 40 patients from the intensive care unit with suspected sepsis. Sepsis was confirmed clinically and/or by positive blood culture. Serum PCT was assayed semi-quantitatively by rapid immunochromatographic technique (within 2 hours of sample receipt. Among 40 critically ill patients, 21 had clinically confirmed sepsis. There were 12 patients with serum PCT ≥10 ng/ml (8, blood culture positive; 1, rickettsia; 2, post-antibiotic blood culture sterile; and 1, non-sepsis; 7 patients with PCT 2-10 ng/ml (4, blood culture positive; 1, falciparum malaria; 2, post-antibiotic blood culture sterile; 3 patients with PCT of 0.5 to 2 ng/ml (sepsis in 1 patient; and 18 patients with PCT < 0.5 ng/ml (sepsis in 2 patients. Patients with PCT ≥ 2 ng/ml had statistically significant correlation with the presence of sepsis (P<0.0001. The PCT assay revealed moderate sensitivity (86% and high specificity (95% at a cut-off ≥ 2 ng/ml. The PCT assay was found to be a useful biomarker of sepsis in this study. The assay could be performed and reported rapidly and provided valuable information before availability of culture results. This might assist in avoiding unwarranted antibiotic usage.

Plasma procalcitonin concentrations are increased in dogs with sepsis

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Goggs, Robert; Milloway, Matthew; Troia, Roberta; Giunti, Massimo

2018-01-01

Sepsis, the life-threatening organ dysfunction caused by a dysregulated host response to infection, is difficult to identify and to prognosticate for. In people with sepsis, procalcitonin (PCT) measurement aids diagnosis, enables therapeutic monitoring and improves prognostic accuracy. This study used a commercial canine PCT assay to measure plasma PCT concentrations in dogs with gastric dilatation volvulus (GDV) syndrome and in dogs with sepsis. It was hypothesised that dogs with GDV syndrome and with sepsis have greater plasma PCT concentrations than healthy dogs and that dogs with sepsis have greater PCT concentrations than dogs with GDV syndrome. Before analysing canine plasma samples, the ability of the assay to identify canine PCT, in addition to assay imprecision and the lower limit of detection were established. The assay had low imprecision with coefficients of variation ≤4.5 per cent. The lower limit of detection was 3.4 pg/ml. Plasma PCT concentrations were measured in 20 dogs with sepsis, in 32 dogs with GDV syndrome and in 52 healthy dogs. Median (IQR) PCT concentration in dogs with sepsis 78.7 pg/ml (39.1–164.7) was significantly greater than in healthy dogs 49.8 pg/ml (36.2–63.7) (P=0.019), but there were no significant differences between PCT concentrations in dogs with GDV syndrome and controls (P=0.072) or between dogs with sepsis and GDV syndrome (P=1.000). Dogs with sepsis have significantly increased plasma PCT concentrations compared with healthy dogs, although considerable overlap between these populations was identified. Future investigations should confirm this finding in other populations and evaluate the diagnostic and prognostic value of PCT in dogs with sepsis. PMID:29682292

An assessment of uncertainty on a LOFT L2-5 LBLOCA PCT based on the ACE-RSM approach: complementary work for the OECD BEMUSE PHASE-III program

International Nuclear Information System (INIS)

Ahn, Kwang Il; Chung, Bub Dong; Lee, John C.

2010-01-01

As pointed out in the OECD BEMUSE Program, when a high computation time is taken to obtain the relevant output values of a complex physical model (or code), the number of statistical samples that must be evaluated through it is a critical factor for the sampling-based uncertainty analysis. Two alternative methods have been utilized to avoid the problem associated with the size of these statistical samples: one is based on Wilks' formula, which is based on simple random sampling, and the other is based on the conventional nonlinear regression approach. While both approaches provide a useful means for drawing conclusions on the resultant uncertainty with a limited number of code runs, there are also some unique corresponding limitations. For example, a conclusion based on the Wilks' formula can be highly affected by the sampled values themselves, while the conventional regression approach requires an a priori estimate on the functional forms of a regression model. The main objective of this paper is to assess the feasibility of the ACE-RSM approach as a complementary method to the Wilks' formula and the conventional regression-based uncertainty analysis. This feasibility was assessed through a practical application of the ACE-RSM approach to the LOFT L2-5 LBLOCA PCT uncertainty analysis, which was implemented as a part of the OECD BEMUSE Phase III program

Corrosion Behavior of Alloy 625 in PbSO4-Pb3O4-PbCl2-ZnO-10 Wt Pct CdO Molten Salt Medium

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Mohammadi Zahrani, E.; Alfantazi, A. M.

2012-08-01

Corrosion behavior and degradation mechanisms of alloy 625 under a 47.288 PbSO4-12.776 Pb3O4-6.844PbCl2-23.108ZnO-10CdO (wt pct) molten salt mixture under air atmosphere were studied at 873 K, 973 K, and 1073 K (600 °C, 700 °C, and 800 °C). Electrochemical impedance spectroscopy (EIS), open circuit potential (OCP) measurements, and potentiodynamic polarization techniques were used to evaluate the degradation mechanisms and characterize the corrosion behavior of the alloy. Morphology, chemical composition, and phase structure of the corrosion products and surface layers of the corroded specimens were studied by scanning electron microscopy/energy-dispersive X-ray (SEM/EDX) and X-ray map analyses. Results confirmed that during the exposure of alloy 625 to the molten salt, chromium was mainly dissolved through an active oxidation process as CrO3, Cr2O3, and CrNbO4, while nickel dissolved only as NiO in the system. Formation of a porous and nonprotective oxide layer with low resistance is responsible for the weak protective properties of the barrier layer at high temperatures of 973 K and 1073 K (700 °C and 800 °C). There were two kinds of attack for INCONEL 625, including general surface corrosion and pitting. Pitting corrosion occurred due to the breakdown of the initial oxide layer by molten salt dissolution of the oxide or oxide cracking.

Web GIS in practice: an interactive geographical interface to English Primary Care Trust performance ratings for 2003 and 2004

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Kamel Boulos Maged N

2004-07-01

Full Text Available Abstract Background On 21 July 2004, the Healthcare Commission http://www.healthcarecommission.org.uk/ released its annual star ratings of the performance of NHS Primary Care Trusts (PCTs in England for the year ending March 2004. The Healthcare Commission started work on 1 April 2004, taking over all the functions of the former Commission for Health Improvement http://www.chi.nhs.uk/, which had released the corresponding PCT ratings for 2002/2003 in July 2003. Results We produced two Web-based interactive maps of PCT star ratings, one for 2003 and the other for 2004 http://healthcybermap.org/PCT/ratings/, with handy functions like map search (by PCT name or part of it. The maps feature a colour-blind friendly quadri-colour scheme to represent PCT star ratings. Clicking a PCT on any of the maps will display the detailed performance report of that PCT for the corresponding year. Conclusion Using our Web-based interactive maps, users can visually appreciate at a glance the distribution of PCT performance across England. They can visually compare the performance of different PCTs in the same year and also between 2003 and 2004 (by switching between the synchronised 'PCT Ratings 2003' and 'PCT Ratings 2004' themes. The performance of many PCTs has improved in 2004, whereas some PCTs achieved lower ratings in 2004 compared to 2003. Web-based interactive geographical interfaces offer an intuitive way of indexing, accessing, mining, and understanding large healthcare information sets describing geographically differentiated phenomena. By acting as an enhanced alternative or supplement to purely textual online interfaces, interactive Web maps can further empower organisations and decision makers.

Procalcitonin and C-reactive protein in urinary tract infection diagnosis.

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Xu, Rui-Ying; Liu, Hua-Wei; Liu, Ji-Ling; Dong, Jun-Hua

2014-05-30

Urinary infections are a common type of pediatric disease, and their treatment and prognosis are closely correlated with infection location. Common clinical manifestations and laboratory tests are insufficient to differentiate between acute pyelonephritis and lower urinary tract infection. This study was conducted to explore a diagnostic method for upper and lower urinary tract infection differentiation. The diagnostic values of procalcitonin (PCT) and C-reactive protein (CRP) were analyzed using the receiver operating characteristic curve method for upper and lower urinary tract infection differentiation. PCT was determined using chemiluminescent immunoassay. The PCT and CRP values in children with acute pyelonephritis were significantly higher than those in children with lower urinary tract infection (3.90 ± 3.51 ng/ml and 68.17 ± 39.42 mg/l vs. 0.48 ± 0.39 ng/ml and 21.39 ± 14.92 mg/l). The PCT values were correlated with the degree of renal involvement, whereas the CRP values failed to show such a significant correlation. PCT had a sensitivity of 90.47% and a specificity of 88% in predicting nephropathia, whereas CRP had sensitivity of 85.71% and a specificity of 48%. Both PCT and CRP can be used for upper and lower urinary tract infection differentiation, but PCT has higher sensitivity and specificity in predicting pyelonephritis than CRP. PCT showed better results than CRP. PCT values were also correlated with the degree of renal involvement.

Procalcitonin levels in patients with positive blood culture, positive body fluid culture, sepsis, and severe sepsis: a cross-sectional study.

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Yu, Ying; Li, Xia-Xi; Jiang, Ling-Xiao; Du, Meng; Liu, Zhan-Guo; Cen, Zhong-Ran; Wang, Hua; Guo, Zhen-Hui; Chang, Ping

2016-01-01

Numerous investigations on procalcitonin (PCT) have been carried out, although few with large sample size. To deal with the complexity of sepsis, an understanding of PCT in heterogeneous clinical conditions is required. Hospitalized patients aged 10-79 years were included in this retrospective and cross-sectional study. PCT tests were assayed within 2 days of blood culture. A total of 2952 cases (from 2538 patients) were enrolled in this study, including 440 cases in the 'positive BC' group, 123 cases in the 'positive body fluid culture' group, and 2389 cases in the 'negative all culture' group. Median PCT values were 4.53 ng/ml, 2.95 ng/ml, and 0.49 ng/ml, respectively. Median PCT values in the gram-negative BC group and gram-positive BC group, respectively, were 6.99 ng/ml and 2.96 ng/ml. Median PCT values in the 'positive hydrothorax culture' group, 'positive ascites culture' group, 'positive bile culture' group, and 'positive cerebrospinal fluid culture' group, respectively, were 1.39 ng/ml, 8.32 ng/ml, 5.98 ng/ml, and 0.46 ng/ml. In all, 357 cases were classified into the 'sepsis' group, 150 of them were classified into the 'severe sepsis' group. Median PCT values were 5.63 ng/ml and 11.06 ng/ml, respectively. PCT could be used in clinical algorithms to diagnose positive infections and sepsis. Different PCT levels could be related to different kinds of microbemia, different infection sites, and differing severity of sepsis.

A new ELISA for the quantification of equine procalcitonin in plasma as potential inflammation biomarker in horses.

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Rieger, Martin; Kochleus, Christian; Teschner, Dana; Rascher, Daniela; Barton, Ann Kristin; Geerlof, Arie; Kremmer, Elisabeth; Schmid, Michael; Hartmann, Anton; Gehlen, Heidrun

2014-09-01

In human medicine, procalcitonin (PCT) is a very common and well-established biomarker for sepsis. Even though sepsis is also a leading cause of death in foals and adult horses, up to now, no data about the role of equine PCT in septic horses has been available. Based on monoclonal antibodies targeted against human PCT, we report here the development of a sandwich ELISA for the quantification of equine PCT in equine plasma samples. The ELISA was characterized for intra- and interassay variance and a working range from 25 to 1,000 ng mL(-1) was defined as within this range; both intra- and interassay variances were below 15 %. The target recovery ranged between 73 and 106 %. The ELISA was used to determine the equine PCT concentration in 24 healthy and 5 septic horses to show the potential for clinical evaluation of equine PCT. Significantly different (P = 0.0006) mean equine PCT concentrations were found for the healthy control group and the sepsis group (47 and 8,450 ng mL(-1)).

Personal carbon trading: A policy ahead of its time?

International Nuclear Information System (INIS)

Fawcett, Tina

2010-01-01

In 2008, the UK government undertook a review of personal carbon trading (PCT) and declared that it was 'an idea currently ahead of its time'. PCT is a radical policy proposal which would entail all adults receiving an equal, tradable carbon allowance to cover emissions from household energy and/or personal travel. The allowance would reduce over time, in line with national emissions reduction goals. The government's key concerns about PCT were its social unacceptability and high cost. This paper reviews the literature and identifies knowledge gaps, and then discusses whether these concerns are justified. Contrary to the government's conclusions, most research shows PCT to be at least as socially acceptable as an alternative taxation policy. People think it could be both fair and effective. Set-up and running costs for PCT will undoubtedly be higher than for alternative taxation policies. However, PCT could deliver benefits from individual and social change motivated by non-economic aspects of the policy. These potential benefits are outlined here. The conclusion is that PCT is a promising and timely policy idea.

Mechanical properties of particulate composites based on a body-centered-cubic Mg-Li alloy containing boron

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Whalen, R. T.; Gonzalez-Doncel, G.; Robinson, S. L.; Sherby, O. D.

1989-01-01

The effect of substituting the Mg metal in Mg-B composites by a Mg-14 wt pct Li solid solution on the ductility of the resulting composite was investigated using elastic modulus measurements on the P/M composite material prepared with a dispersion of B particles (in a vol pct range of 0-30) in a matrix of Mg-14 wt pct Li-1.5 wt pct Al. It was found that the elastic modulus of the composites increased rapidly with increasing boron, with specific stiffness values reaching about two times that of most structural materials. The values of the compression and tensile strengths increased significantly with boron additions. Good tensile ductility was achieved at the level of 10 vol pct B. However, at 20 vol pct B, the Mg-Li composite exhibited only limited tensile ductility (about 2 percent total elongation).

Effect of Temperature and Fluid Flow on Dendrite Growth During Solidification of Al-3 Wt Pct Cu Alloy by the Two-Dimensional Cellular Automaton Method

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Gu, Cheng; Wei, Yanhong; Liu, Renpei; Yu, Fengyi

2017-12-01

A two-dimensional cellular automaton-finite volume model was developed to simulate dendrite growth of Al-3 wt pct Cu alloy during solidification to investigate the effect of temperature and fluid flow on dendrite morphology, solute concentration distribution, and dendrite growth velocity. Different calculation conditions that may influence the results of the simulation, including temperature and flow, were considered. The model was also employed to study the effect of different undercoolings, applied temperature fields, and forced flow velocities on solute segregation and dendrite growth. The initial temperature and fluid flow have a significant impact on the dendrite morphologies and solute profiles during solidification. The release of energy is operated with solidification and results in the increase of temperature. A larger undercooling leads to larger solute concentration near the solid/liquid interface and solute concentration gradient at the same time-step. Solute concentration in the solid region tends to increase with the increase of undercooling. Four vortexes appear under the condition when natural flow exists: the two on the right of the dendrite rotate clockwise, and those on the left of the dendrite rotate counterclockwise. With the increase of forced flow velocity, the rejected solute in the upstream region becomes easier to be washed away and enriched in the downstream region, resulting in acceleration of the growth of the dendrite in the upstream and inhibiting the downstream dendrite growth. The dendrite perpendicular to fluid flow shows a coarser morphology in the upstream region than that of the downstream. Almost no secondary dendrite appears during the calculation process.

Diagnosis of pheochromocytoma using (123I)-compared with (131I)-metaiodobenzylguanidine scintigraphy

International Nuclear Information System (INIS)

Furuta, Nozomu; Kiyota, Hiroshi; Yoshigoe, Fukuo; Hasegawa, Norio; Ohishi, Yukihiko

1999-01-01

Patient with pheochromocytoma (PCT) cannot be cured without operation, therefore, preoperative determination of the localization of PCT should be performed accurately. ( 131 I)-Metaiodobenzylguanidine (MIBG) scintigraphy is a gold standard for the diagnosis of PCT. However, ( 123 I)-MIBG is also found to accumulate in PCT. In order to clarify the usefulness of ( 123 I)-MIBG scintigraphy for the local detection of PCT, we compared the distribution of ( 123 I)- and ( 131 I)-MIBG in patients with or without PCT. ( 131 I)- and ( 123 I)-MIBG scintigraphy was performed in 29 and 16 patients, respectively. In the former group, 14 patients had PCT, 12 had hypertension without any adrenal disorder and three had other diseases. In the latter group, eight patients had PCT, two had hypertension without any adrenal disorder and six had other diseases. The sensitivity, specificity and accuracy of ( 123 I)- with ( 131 I)-MIBG scintigraphy were compared. The sensitivity of ( 131 I)- and ( 123 I)-MIBG scintigraphy was 85.7 and 90%, respectively. The specificity of each test was 100%. The accuracy of ( 131 I)- and ( 123 I)-MIBG scintigraphy was 93.1 and 95%, respectively. The quality of images obtained using ( 123 I)-MIBG was better than with ( 131 I)-MIBG, because ( 123 I)-MIBG generated a higher dose of γ-rays with a higher specificity than ( 131 I)-MIBG. In addition, normal adrenal grands were visualized in 50% of patients tested with ( 123 I)-MIBG scintigraphy. These results indicate that ( 123 I)-MIBG scintigraphy is a valuable tool for the local detection of PCT, as is ( 131 I)-MIBG scintigraphy. Furthermore, it is possible that ( 123 I)-MIBG can be used as an alternative to ( 131 I)-MIBG for the detection of PCT. Our study was not a prospective study and the background of the patients was not matched. Further prospective studies are needed in order to determine the efficacy of ( 123 I)-MIBG scintigraphy for the diagnosis of PCT. (author)

Pupil cycle time and contrast sensitivity in type II diabetes mellitus patients: A pilot study

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Hoyoung Lee

2011-01-01

Full Text Available Context: Pupil cycle time (PCT has been widely used for examination of ocular diabetic autonomic neuropathy (DAN. Aims: The primary aim of this study was to evaluate the difference of contrast sensitivity according to PCT results, and the secondary aim was to determine the factors associated with PCT difference for type II diabetes patients. Settings and Design: A clinical pilot study that included a total of 60 eyes of 60 type II diabetes patients. Materials and Methods: We divided all patients into three groups according to PCT results. Group A and Group C were composed of patients who had upper one third PCT and lower one third PCT, respectively. We analyzed difference of age, diabetes duration, hypertension duration, mean best corrected visual acuity (BCVA, mean spherical equivalent (SE, HbA1C, glomerular filtration rate (GFR, stage of diabetic retinopathy, and Cardiac Autonomic Function Score (CAFS. Contrast sensitivity and decrease of visual acuity by glare were also estimated and analyzed for 28 eyes of 28 non-proliferative diabetic retinopathy (NPDR patients. Group [NPDR] A and Group [NPDR] C were defined as those who had lower one third PCT and upper one third PCT, respectively. Statistical Analysis: Statistical analysis was done using SPSS 17.0 software. Results and Conclusions: Each group contained 20 eyes. Significant differences between Group A and Group C were observed in duration of diabetes and CAFS (P ≤ 0.001 and P < 0.001, respectively. Contrast sensitivity in Group [NPDR] A was significantly more than in Group [NPDR] C at all cpds (all P ≤ 0.001. We found that PCT can influence contrast sensitivity or glare in diabetes patients and also confirmed a significant correlation of PCT with CAFS and duration of diabetes.

Procalcitonin Identifies Cell Injury, Not Bacterial Infection, in Acute Liver Failure.

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Jody A Rule

Full Text Available Because acute liver failure (ALF patients share many clinical features with severe sepsis and septic shock, identifying bacterial infection clinically in ALF patients is challenging. Procalcitonin (PCT has proven to be a useful marker in detecting bacterial infection. We sought to determine whether PCT discriminated between presence and absence of infection in patients with ALF.Retrospective analysis of data and samples of 115 ALF patients from the United States Acute Liver Failure Study Group randomly selected from 1863 patients were classified for disease severity and ALF etiology. Twenty uninfected chronic liver disease (CLD subjects served as controls.Procalcitonin concentrations in most samples were elevated, with median values for all ALF groups near or above a 2.0 ng/mL cut-off that generally indicates severe sepsis. While PCT concentrations increased somewhat with apparent liver injury severity, there were no differences in PCT levels between the pre-defined severity groups-non-SIRS and SIRS groups with no documented infections and Severe Sepsis and Septic Shock groups with documented infections, (p = 0.169. PCT values from CLD patients differed from all ALF groups (median CLD PCT value 0.104 ng/mL, (p ≤0.001. Subjects with acetaminophen (APAP toxicity, many without evidence of infection, demonstrated median PCT >2.0 ng/mL, regardless of SIRS features, while some culture positive subjects had PCT values <2.0 ng/mL.While PCT appears to be a robust assay for detecting bacterial infection in the general population, there was poor discrimination between ALF patients with or without bacterial infection presumably because of the massive inflammation observed. Severe hepatocyte necrosis with inflammation results in elevated PCT levels, rendering this biomarker unreliable in the ALF setting.

Analytical evaluation of the novel Lumipulse G BRAHMS procalcitonin immunoassay.

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Ruzzenente, Orazio; Salvagno, Gian Luca; Gelati, Matteo; Lippi, Giuseppe

2016-12-01

This study was designed to evaluate the analytical performance of the novel Lumipulse G1200 BRAHMS procalcitonin (PCT) immunoassay. This analytical evaluation encompassed the calculation of the limit of blank (LOB), limit of detection (LOD), functional sensitivity, intra- and inter-assay imprecision, confirmation of linearity and a comparison with the Vidas BRAHMS PCT assay. The LOB, LOD and functional sensitivity were 0.0010 ng/mL, 0.0016 ng/mL and 0.008 ng/mL, respectively. The total analytical imprecision was found to be 2.1% and the linearity was excellent (r=1.00) in the range of concentrations between 0.006-75.5 ng/mL. The correlation coefficient with Vidas BRAHMS PCT was 0.995 and the equation of the Passing and Bablok regression analysis was [Lumipulse G BRAHMS PCT]=0.76×[Vidas BRAHMS PCT]+0.04. The mean overall bias of Lumipulse G BRAHMS PCT versus Vidas BRAHMS PCT was -3.03 ng/mL (95% confidence interval [CI]: -4.32 to -1.74 ng/mL), whereas the mean bias in samples with PCT concentration between 0-10 ng/mL was -0.49 ng/mL (95% CI: -0.77 to -0.24 ng/mL). The diagnostic agreement was 100% at 0.5 ng/mL, 97% at 2.0 ng/mL and 95% at 10 ng/mL, respectively. These results attest that Lumipulse G BRAHMS PCT exhibits excellent analytical performance, among the best of the methods currently available on the diagnostic market. However, the significant bias compared to the Vidas BRAHMS PCT suggests that the methods cannot be used interchangeably.

Thermodynamics Calculation and Experimental Study on Separation of Bismuth from a Bismuth Glance Concentrate Through a Low-Temperature Molten Salt Smelting Process

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Yang, Jian-Guang; He, De-Wen; Tang, Chao-Bo; Chen, Yong-Ming; Sun, Ya-Hui; Tang, Mo-Tang

2011-08-01

The main purpose of this study is to characterize and separate bismuth from a bismuth glance concentrate through a low-temperature, sulfur-fixing smelting process. This article reports on a study conducted on the optimization of process parameters, such as Na2CO3 and zinc oxide wt pct in charging, smelting temperature, smelting duration on the bismuth yield, resultant crude bismuth grade, and sulfur-fixing rate. A maximum bismuth recovery of 97.31 pct, crude bismuth grade of 96.93 pct, and 98.23 pct sulfur-fixing rate are obtained when a charge (containing 63.50 wt pct of Na2CO3 and 22.50 wt pct of bismuth glance, as well as 5 pct in excess of the stoichiometric requirement of zinc oxide dosage) is smelted at 1000 K (727 °C) for 150 minutes. This smelting operation is free from atmospheric pollution because zinc oxide is used as the sulfur-fixing agent, which can capture sulfur from bismuth sulfide and form the more thermodynamic-stable compound, zinc sulfide. The solid residue is subjected to a mineral dressing operation to obtain suspension, which is filtered to produce a cake, representing the solid particles of zinc sulfide. Based on the results of the chemical content analysis of the as-resultant zinc sulfide, more than 93 pct zinc sulfide can be recovered, and the recovered zinc sulfide grade can reach 60.20 pct. This material can be sold as zinc sulfide concentrate or roasted to be regenerated as zinc oxide.

RELAP 5 Simulations of a hypothetical LOCA in Ringhals 2

International Nuclear Information System (INIS)

Caraher, D.

1987-01-01

RELAP5 simulations of a hypothetical LOCA in Ringhals 2 were conducted in order to determine the sensitivity of the calculated peak cladding temperature (PCT) to Appendix K requirements. The PCT was most sensitive to the assumed model decay heat: Changing from the 1979 ANS Standard to 1.2 times the 1973 Standard increased the PCT by 70 to 100K. After decay heat, the two parameters which affected the PCT the most were steam generator heat transfer and heat transfer lockout. The PCT was not sensitive to the assumed pump rotor condition (locked vs coasting); nor was it sensitive to a modest amount (5 to 10%) of steam generator tube plugging. (author)

Procalcitonin, C-reactive protein and serum lactate dehydrogenase in the diagnosis of bacterial sepsis, SIRS and systemic candidiasis.

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Miglietta, Fabio; Faneschi, Maria Letizia; Lobreglio, Giambattista; Palumbo, Claudio; Rizzo, Adriana; Cucurachi, Marco; Portaccio, Gerolamo; Guerra, Francesco; Pizzolante, Maria

2015-09-01

The aim of this study was to evaluate procalcitonin (PCT), C-reactive protein (CRP), platelet count (PLT) and serum lactate dehydrogenase (LDH) as early markers for diagnosis of SIRS, bacterial sepsis and systemic candidiasis in intensive care unit (ICU) patients. Based on blood culture results, the patients were divided into a sepsis group (70 patients), a SIRS group (42 patients) and a systemic candidiasis group (33 patients). PCT, CRP, LDH and PLT levels were measured on day 0 and on day 2 from the sepsis symptom onset. PCT levels were higher in Gram negative sepsis than those in Gram positive sepsis, although the P value between the two subgroups is not significant (P=0.095). Bacterial sepsis group had higher PCT and CRP levels compared with the systemic candidiasis group, whereas PLT and LDH levels showed similar levels in these two subgroups. The AUC for PCT (AUC: 0.892, P candidiasis groups (P=0.093 N.S.). In conclusion, PCT can be used as a preliminary marker in the event of clinical suspicion of systemic candidiasis; however, low PCT levels (candidiasis and SIRS groups.

Accuracy of the detection of infratentorial stroke lesions using perfusion CT: an experimenter-blinded study

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Lee, In Hyouk; Kim, Myung Soon; Kim, Young Ju; Lee, Myeong Sub [Yonsei University, Department of Radiology, Wonju College of Medicine, Wonju (Korea, Republic of); You, Joshua H. [Center for Health, Wellness, Fitness, Prevention, and Healing Across the Life Span, Department of Physical Therapy, Graduate School of Rehabilitation Science, Yonsei University, Center for Movement Impairment Solutions, Wonju City (Korea, Republic of); Lee, Ji Yong [Yonsei University, Department of Neurology, Wonju College of Medicine, Wonju (Korea, Republic of); Whang, Kum [Yonsei University, Department of Neurosurgery, Wonju College of Medicine, Wonju (Korea, Republic of)

2010-12-15

Although perfusion CT (PCT) for the detection of supratentorial stroke is well established, there is a dearth of evidence of its effectiveness in the detection of infratentorial stroke. Hence, this study compared sensitivity, specificity, and accuracy of PCT maps between infratentorial and supratentorial stroke lesions. One hundred patients with acute stroke who had successfully undergone near whole-brain PCT with the toggling table technique and follow-up MRI were included. Wilcoxon Mann-Whitney test was performed at P < 0.01. There was no significant statistical difference in the accuracy (91.79% vs. 93.23% in regional cerebral blood volume; 92.26% vs. 95.31% in regional cerebral blood flow; 89.17% vs. 92.71% in mean transit time; 89.76% vs. 92.19% in time to peak; P > 0.01 in all PCT maps) between supratentorial and infratentorial stroke. Also, there was no remarkable difference in both sensitivity and specificity of PCT maps. This was the first study to investigate the accuracy of PCT with the toggling table technique in detection of infratentorial stroke lesions. Clinically, PCT is highly reliable and accurate in detecting infratentorial stroke lesions. (orig.)

A procalcitonin-based algorithm to guide antibiotic therapy in secondary peritonitis following emergency surgery: a prospective study with propensity score matching analysis.

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Huang, Ting-Shuo; Huang, Shie-Shian; Shyu, Yu-Chiau; Lee, Chun-Hui; Jwo, Shyh-Chuan; Chen, Pei-Jer; Chen, Huang-Yang

2014-01-01

Procalcitonin (PCT)-based algorithms have been used to guide antibiotic therapy in several clinical settings. However, evidence supporting PCT-based algorithms for secondary peritonitis after emergency surgery is scanty. In this study, we aimed to investigate whether a PCT-based algorithm could safely reduce antibiotic exposure in this population. From April 2012 to March 2013, patients that had secondary peritonitis diagnosed at the emergency department and underwent emergency surgery were screened for eligibility. PCT levels were obtained pre-operatively, on post-operative days 1, 3, 5, and 7, and on subsequent days if needed. Antibiotics were discontinued if PCT was Advanced age, coexisting pulmonary diseases, and higher severity of illness were significantly associated with longer durations of antibiotic use. The PCT-based algorithm safely reduces antibiotic exposure in this study. Further randomized trials are needed to confirm our findings and incorporate cost-effectiveness analysis. Australian New Zealand Clinical Trials Registry ACTRN12612000601831.

Differentiation between malignant and benign solitary pulmonary nodules: Use of volume first-pass perfusion and combined with routine computed tomography

International Nuclear Information System (INIS)

Shan, Fei; Zhang, Zhiyong; Xing, Wei; Qiu, Jianguo; Yang, Shan; Wang, Jian; Jiang, Yaping; Chen, Gang

2012-01-01

Purpose: To evaluate the capability of first-pass volume perfusion computed tomography (PCT) for differentiation of solitary pulmonary nodules (SPNs) and to compare that of combination of PCT and routine CT with CT alone for the differentiation. Materials and methods: Our institutional review board approved this study and informed consent was obtained. With nine excluded, 65 consecutive patients having a SPN with histopathologic proof or follow-up underwent a 30 s PCT using the deconvolution model were evaluated. Kruskal–Wallis tests and receiver operating characteristics (ROC) analysis were underwent. Four radiologists assessed nodules independently and retrospectively. Diagnostic capability was compared for CT alone and PCT plus CT. ROC analysis, McNemar test, and weighted kappa statistics were performed. Results: Significant differences were found in parameters between malignant and benign nodules (p < 0.0001 for blood flow, blood volume, and permeability surface area product), SPNs were more likely to be malignant by using threshold values of more than 55 ml/100 g/min, 2.5 ml/100 g, and 10 ml/100 g/min, respectively. PCT plus CT was significantly better in overall sensitivity (93%, p = 0.004) and accuracy (94%, p = 0.003) compared to CT alone, not specificity (96%). Area under the curve for ROC analyses of PCT plus CT was significantly larger than that of CT alone (p = 0.018). Mean weighted kappa for PCT plus CT was 0.715, that for CT alone was 0.447. Conclusion: Volume first-pass PCT can distinguish SPNs. Using PCT plus routine CT may be more sensitive and accurate for differentiating malignant from benign nodules than CT alone and allows more confidence and constancy.

Differentiation between malignant and benign solitary pulmonary nodules: Use of volume first-pass perfusion and combined with routine computed tomography

Energy Technology Data Exchange (ETDEWEB)

Shan, Fei, E-mail: shanfeiqz@gmail.com [Department of Radiology, Third Affiliated Hospital of Suzhou University, 185, Juqian Road, Changzhou, Zip Code: 213003 (China); Zhang, Zhiyong, E-mail: zhangzy@fudan.edu.cn [Department of Radiology, Zhongshan Hospital Fudan University, 180, Fenglin Road, Shanghai, Zip Code: 200032 (China); Xing, Wei, E-mail: suzhxingwei@126.com [Department of Radiology, Third Affiliated Hospital of Suzhou University, 185, Juqian Road, Changzhou, Zip Code: 213003 (China); Qiu, Jianguo, E-mail: step9999@sina.com [Department of Radiology, Third Affiliated Hospital of Suzhou University, 185, Juqian Road, Changzhou, Zip Code: 213003 (China); Yang, Shan, E-mail: yang.shan@zs-hospital.sh.cn [Department of Radiology, Zhongshan Hospital Fudan University, 180, Fenglin Road, Shanghai, Zip Code: 200032 (China); Wang, Jian, E-mail: wang.jian@zs-hospital.sh.cn [Department of Radiology, Zhongshan Hospital Fudan University, 180, Fenglin Road, Shanghai, Zip Code: 200032 (China); Jiang, Yaping, E-mail: jiang.yaping@zs-hospital.sh.cn [Department of Radiology, Zhongshan Hospital Fudan University, 180, Fenglin Road, Shanghai, Zip Code: 200032 (China); Chen, Gang, E-mail: chen.gang@zs-hospital.sh.cn [Department of Radiology, Zhongshan Hospital Fudan University, 180, Fenglin Road, Shanghai, Zip Code: 200032 (China)

2012-11-15

Purpose: To evaluate the capability of first-pass volume perfusion computed tomography (PCT) for differentiation of solitary pulmonary nodules (SPNs) and to compare that of combination of PCT and routine CT with CT alone for the differentiation. Materials and methods: Our institutional review board approved this study and informed consent was obtained. With nine excluded, 65 consecutive patients having a SPN with histopathologic proof or follow-up underwent a 30 s PCT using the deconvolution model were evaluated. Kruskal-Wallis tests and receiver operating characteristics (ROC) analysis were underwent. Four radiologists assessed nodules independently and retrospectively. Diagnostic capability was compared for CT alone and PCT plus CT. ROC analysis, McNemar test, and weighted kappa statistics were performed. Results: Significant differences were found in parameters between malignant and benign nodules (p < 0.0001 for blood flow, blood volume, and permeability surface area product), SPNs were more likely to be malignant by using threshold values of more than 55 ml/100 g/min, 2.5 ml/100 g, and 10 ml/100 g/min, respectively. PCT plus CT was significantly better in overall sensitivity (93%, p = 0.004) and accuracy (94%, p = 0.003) compared to CT alone, not specificity (96%). Area under the curve for ROC analyses of PCT plus CT was significantly larger than that of CT alone (p = 0.018). Mean weighted kappa for PCT plus CT was 0.715, that for CT alone was 0.447. Conclusion: Volume first-pass PCT can distinguish SPNs. Using PCT plus routine CT may be more sensitive and accurate for differentiating malignant from benign nodules than CT alone and allows more confidence and constancy.

Porfiria cutánea tardía: Reporte de 5 casos Porphyria cutanea tarda: Five cases report

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J L Iribas

2008-03-01

Full Text Available La PCT es la más común de las porfirias. Es una fotodermatosis que resulta de la deficiencia de la UPD, enzima perteneciente a la vía de síntesis del hemo. Presentamos la evolución de cinco casos de PCT; cuatro de PCT familiar y uno de PCT esporádica. En dos de los pacientes pertenecientes al grupo de PCT tipo II, encontramos como factor de riesgo, el consumo de alcohol, y en la paciente con PCT tipo I se detectó serología positiva para VHC. Todos los pacientes fueron tratados con cloroquina y flebotomías repetidas. Rápidamente se detectó mejoría clínica y bioquímica. Se observó que la porfirinuria continuó en descenso aún luego de suspendida la terapéutica. Tres de los pacientes con PCT familiar persisten en remisión clínica y con ausenciade recaídas tras más de 10 años de seguimiento. Aconsejamos en pacientes que padecen PCT la búsqueda de factores asociados (VHC, HIV, genes de HH y desencadenantes exógenos (consumo excesivo de alcohol, hierro en la dieta e ingesta de estrógenos que de ser controlados o evitados, junto con el tratamiento oportuno, contribuyen a un satisfactorio control de la enfermedad.The porphyria cutanea tarda is the most frequent porphyria, it is a photodermatosis secondary to uroporphyrinogen decarboxylase deficiency; this enzyme belongs to the haem synthesis pathway. We present on this paper the evolution of five cases of PCT, four of them with familiar type and one of them sporadic type. In two patients belonging to PCT type II, we found alcohol addiction as a serious risk, while on the other patients PCT type I we found HCV positive serology. All patients were treated with chloroquine and phlebotomies. We could observe a good response not only clinical but biochemical. We could also see that the porphyrins urinary level continued descending once the drug was withdrew. Three of the patients with familiar PCT remains in clinical remission without any relapses in ten years of control. We advice

HOME COST Pct Mortgaged Units by Costs as Pct 1999 HH Income NMSD 2000

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Earth Data Analysis Center, University of New Mexico — The 2006 Second Edition TIGER/Line files are an extract of selected geographic and cartographic information from the Census TIGER database. The geographic coverage...

Procalcitonin-guided antibiotic treatment in critically ill patients.

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Hohn, Andreas; Heising, Bernhard; Schütte, Jan-Karl; Schroeder, Olaf; Schröder, Stefan

2017-02-01

In critically ill patients, length of antibiotic treatment can be effectively guided by procalcitonin (PCT) protocols. International sepsis guidelines and guidelines on antibiotic stewardship strategies recommend PCT as helpful laboratory marker for a rational use of antibiotics. A number of studies and meta-analyses have confirmed the effectiveness of PCT-protocols for shortening antibiotic treatment without compromising clinical outcome in critically ill patients. But in clinical practice, there is still uncertainty how to interpret PCT levels and how to adjust antibiotic treatment in various infectious situations, especially in the perioperative period. This narrative review gives an overview on the application of PCT-protocols in critically ill patients with severe bacterial infections on the basis of 5 case reports and the available literature. Beside strengths and limitations of this biomarker, also varying kinetics and different maximum values with regard to the infectious focus and pathogens are discussed. PCT-guided antibiotic treatment appears to be safe and effective. Most of the studies revealed a shorter antibiotic treatment without negative clinical outcomes. Cost effectiveness is still a matter of debate and effects on bacterial resistance due to shorter treatments, possible lower rates of drug-related adverse events, or decreased rates of Clostridium difficile infections are not yet evaluated. Guidance of antibiotic treatment can effectively be supported by PCT-protocols. However, it is important to consider the limitations of this biomarker and to use PCT protocols along with antibiotic stewardship programmes and regular clinical rounds together with infectious diseases specialists.

The value of serum procalcitonin content for assessing the inflammation and organ injury in neonatal septicemia

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Shao-Fang Li1

2017-04-01

Full Text Available Objective: To study the value of serum procalcitonin content for assessing the inflammation and organ injury in neonatal septicemia. Methods: 48 children with neonatal septicemia who were treated in our hospital between April 2014 and May 2016 were selected as the observation group, 50 healthy newborns who were delivered in our hospital during the same period were selected as the normal control group, and the observation group were further divided into high PCT group and low PCT group (n=24 according to the median of serum PCT content. Enzyme-linked immunosorbent assay (ELISA was used to detect the serum contents of inflammatory mediators, and color Doppler diasonograph was used to measure heart injury index levels. Results: Peripheral blood PCT content of observation group was significantly higher than that of control group (P<0.05; serum inflammatory mediators IL-1β, IL-6, IL-8 and TNF-α contents of high PCT group and low PCT group were significantly higher than those of normal control group, and as the PCT content increased, serum inflammatory mediators interleukin-1β (IL-1β, interleukin-6 (IL-6, interleukin-8 (IL-8 and tumor necrosis factor-α (TNF-α contents increased (P<0.05; routine ultrasound parameters cardiac output (CO and left ventricular ejection fraction (LVEF levels as well as the absolute value of twodimensional speckle tracking imaging parameters left ventricular global longitudinal strain rate (GLSr and left ventricular global circumferential strain rate (GCSr of high PCT group and low PCT group were lower than those of normal control group while serum myocardial injury indexes cardiac troponin I (cTnI, heart-type fatty acid-binding protein (H-FABP and α-hydroxybutyric dehydrogenase (HBDH contents were higher than those of normal control group, and as the PCT content increased, CO and LVEF levels as well as the absolute value of GLSr and GCSr decreased while the indexes cTnI, H-FABP and HBDH contents increased (P<0

Effects of Non-metallic Inclusions on Hot Ductility of High Manganese TWIP Steels Containing Different Aluminum Contents

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Wang, Yu-Nan; Yang, Jian; Wang, Rui-Zhi; Xin, Xiu-Ling; Xu, Long-Yun

2016-06-01

The characteristics of inclusions in Fe-16Mn- xAl-0.6C ( x = 0.002, 0.033, 0.54, 2.10 mass pct) steels have been investigated and their effects on hot ductility of the high manganese TWIP steels have been discussed. Ductility is very poor in the steel containing 0.54 mass pct aluminum, which is lower than 20 pct in the temperature range of 873 K to 1473 K (600 °C to 1200 °C). For the steels containing 0.002 and 2.10 mass pct aluminum, ductility is higher than 40 pct in the same temperature range. The hot ductility of steel containing 0.033 mass pct aluminum is higher than 30 pct throughout the temperature range under examination. With increasing aluminum content, the main inclusions in the steels change along the route of MnO/(MnO + MnS) → MnS/(Al2O3 + MnS) → AlN/(Al2O3 + MnS)/(MgAl2O4 + MnS) → AlN. The thermodynamic results of inclusion types calculated with FactSage software are in agreement with the experimental observation results. The inclusions in the steels containing 0.002 mass pct aluminum do not deteriorate the hot ductility. MnS inclusions whose average size, number density, and volume ratio are 1.12 μm, 15.62 mm-2, and 2.51 × 10-6 in the steel containing 0.033 mass pct aluminum reduce the ductility. In the steel containing 0.54 mass pct aluminum, AlN inclusions whose average size, number density, and volume ratio are 0.878 μm, 16.28 mm-2 and 2.82 × 10-6 can precipitate at the austenite grain boundaries, prevent dynamic recrystallization and deteriorate the hot ductility. On the contrary, in the steel containing 2.10 mass pct aluminum, the average size, number density and volume ratio of AlN inclusions change to 2.418 μm, 35.95 mm-2, and 2.55 × 10-5. They precipitate in the matrix, which do not inhibit dynamic recrystallization and thereby do not lead to poor hot ductility.

Mercury embrittlement of Cu-Al alloys under cyclic loading

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Regan, T. M.; Stoloff, N. S.

1977-01-01

The effect of mercury on the room temperature, high cycle fatigue properties of three alloys: Cu-5.5 pct Al, Cu-7.3 pct Al, and Cu-6.3 pct Al-2.5 pct Fe has been determined. Severe embrittlement under cyclic loading in mercury is associated with rapid crack propagation in the presence of the liquid metal. A pronounced grain size effect is noted under mercury, while fatigue properties in air are insensitive to grain size. The fatigue results are discussed in relation to theories of adsorption-induced liquid metal embrittlement.

Improved ductility of Ni3Si by microalloying with boron or carbon

International Nuclear Information System (INIS)

Taub, A.I.; Briant, C.L.

1989-01-01

The effects of boron and carbon additions on the tendency for intergranular fracture in trinickel silicide intermetallics are reported. Melt spinning of Ni 77 Si 23 alloyed with 0.1 at. pct boron results in full bend ductility and complete transgranular fracture compared with brittle intergranular fracture for the unmodified compound. Alloying with 0.1 at. pct carbon also produced full bend ductility but a mixed mode failure (30 pct transgranular). For both carbon and boron additions, reducing the Ni concentration of the base compound results in a greater percentage of intergranular fracture. For Ni 77 Si 23 , the solubility limit is between 0.1 and 0.2 t. pct boron. For compounds with silicon concentrations of 23.5 and 24.0 at. pct, the solubility limit is less than 0.1 at. pct boron. Boron additions above the solubility limit result in Ni 3 B precipitates which degrade the bend ductility and increase the percentage of intergranular fracture. Alloying with carbon above the solubility limit ( 77 Si 23 , increasing the carbon concentration from 0.1 to 1.0 at. pct resulted in no change in the ductility. Auger examination of the grain boundary composition showed strong segregation of both boron and carbon. Enrichment in silicon concentration was also observed

Dual-Quantum-Dots-Labeled Lateral Flow Strip Rapidly Quantifies Procalcitonin and C-reactive Protein

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Qi, XiaoPing; Huang, YunYe; Lin, ZhongShi; Xu, Liang; Yu, Hao

2016-03-01

In the article, a dual-quantum-dots-labeled (dual-QDs-labeled) lateral flow strip (LFS) method was developed for the simultaneous and rapid quantitative detection of procalcitonin (PCT) and C-reactive protein (CRP) in the blood. Two QD-antibody conjugates with different fluorescence emission spectra were produced and sprayed on the LFS to capture PCT and CRP in the blood. Furthermore, a double antibody sandwich method for PCT and, meanwhile, a competitive inhibition method for CRP were employed in the LFS. For PCT and CRP in serum assayed by the dual-QDs-labeled LFS, their detection sensitivities reached 0.1 and 1 ng/mL, respectively, and their linear quantitative detection ranges were from 0.3 to 200 ng/mL and from 50 to 250 μg/mL, respectively. There was little evidence that the PCT and CRP assays would be interfered with each other. The correlations for testing CRP and PCT in clinical samples were 99.75 and 97.02 %, respectively, between the dual-QDs-labeled LFS we developed and commercial methods. The rapid quantification of PCT and CRP on dual-QDs-labeled LFS is of great clinical value to distinguish inflammation, bacterial infection, or viral infection and to provide guidance for the use of antibiotics or other medicines.

Cerebral blood volume imaging by flat detector computed tomography in comparison to conventional multislice perfusion CT

International Nuclear Information System (INIS)

Struffert, Tobias; Kloska, Stephan; Engelhorn, Tobias; Doerfler, Arnd; Deuerling-Zheng, Yu; Boese, Jan; Zellerhoff, Michael; Schwab, Stefan

2011-01-01

We tested the hypothesis that Flat Detector computed tomography (FD-CT) with intravenous contrast medium would allow the calculation of whole brain cerebral blood volume (CBV) mapping (FD-CBV) and would correlate with multislice Perfusion CT (PCT). Twenty five patients were investigated with FD-CBV and PCT. Correlation of the CBV maps of both techniques was carried out with measurements from six anatomical regions from both sides of the brain. Mean values of each region and the correlation coefficient were calculated. Bland-Altman analysis was performed to compare the two different imaging techniques. The image and data quality of both PCT and FD-CBV were suitable for evaluation in all patients. The mean CBV values of FD-CBV and PCT showed only minimal differences with overlapping standard deviation. The correlation coefficient was 0.79 (p < 0.01). Bland-Altman analysis showed a mean difference of -0.077 ± 0.48 ml/100 g between FD-CBV and PCT CBV measurements, indicating that FD-CBV values were only slightly lower than those of PCT. CBV mapping with intravenous contrast medium using Flat Detector CT compared favourably with multislice PCT. The ability to assess cerebral perfusion within the angiographic suite may improve the management of ischaemic stroke and evaluation of the efficacy of dedicated therapies. (orig.)

Motion estimation using point cluster method and Kalman filter.

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Senesh, M; Wolf, A

2009-05-01

The most frequently used method in a three dimensional human gait analysis involves placing markers on the skin of the analyzed segment. This introduces a significant artifact, which strongly influences the bone position and orientation and joint kinematic estimates. In this study, we tested and evaluated the effect of adding a Kalman filter procedure to the previously reported point cluster technique (PCT) in the estimation of a rigid body motion. We demonstrated the procedures by motion analysis of a compound planar pendulum from indirect opto-electronic measurements of markers attached to an elastic appendage that is restrained to slide along the rigid body long axis. The elastic frequency is close to the pendulum frequency, as in the biomechanical problem, where the soft tissue frequency content is similar to the actual movement of the bones. Comparison of the real pendulum angle to that obtained by several estimation procedures--PCT, Kalman filter followed by PCT, and low pass filter followed by PCT--enables evaluation of the accuracy of the procedures. When comparing the maximal amplitude, no effect was noted by adding the Kalman filter; however, a closer look at the signal revealed that the estimated angle based only on the PCT method was very noisy with fluctuation, while the estimated angle based on the Kalman filter followed by the PCT was a smooth signal. It was also noted that the instantaneous frequencies obtained from the estimated angle based on the PCT method is more dispersed than those obtained from the estimated angle based on Kalman filter followed by the PCT method. Addition of a Kalman filter to the PCT method in the estimation procedure of rigid body motion results in a smoother signal that better represents the real motion, with less signal distortion than when using a digital low pass filter. Furthermore, it can be concluded that adding a Kalman filter to the PCT procedure substantially reduces the dispersion of the maximal and minimal

Increased FDG bone marrow uptake after intracoronary progenitor cell therapy

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Doebert, N.; Menzel, C.; Diehl, M.; Hamscho, N.; Zaplatnikov, K.; Gruenwald, F. [Dept. of Nuclear Medicine, Univ. of Frankfurt (Germany)

2005-02-01

Patients with coronary artery disease who undergo FDG PET for therapy monitoring after intracoronary progenitor cell infusion (PCT) show an increased bone marrow uptake in some cases. Aim of the study was to evaluate the systemic bone marrow glucose metabolism in this patient group after PCT. Patients, methods: FDG bone marrow uptake (BMU), measured as standardized uptake value (SUVmax) in the thoracic spine, was retrospectively evaluated in 23 control patients who did not receive PCT and in 75 patients who received PCT 3{+-}2.2 days before PET scanning. Five out of them were pretreated with granulocyte colony-stimulating factor (G-CSF) 5 days prior to PCT and 10{+-}1.2 days before PET scanning. In 39 patients who received only PCT without G-CSF and underwent PET therapy monitoring 4 months later, baseline and follow up bone marrow uptake were measured. Leucocytes, C-reactive protein (CRP) levels and the influence of nicotine consumption were compared with the BMU. Results: In patients (n=70) who received PCT without G-CSF, BMU media (1.3) was slightly, but significantly higher than in the controls (1.0) (p=0.02) regardless nicotine consumption. BMU did not change significantly 4 months later (1.2) (p=0.41, n.s.). After G-CSF pretreatment, patients showed a significantly higher bone marrow uptake (3.7) compared to patients only treated with PCT (1.3) (p=0.023). Leucocyte blood levels were significantly higher in patients with a BMU {>=}2.5 compared to patients with a bone marrow SUVmax<2.5 (p<0.001). CRP values did not correlate with the BMU (rho -0.02, p=0.38). Conclusion: Monitoring PCT patients, a slightly increased FDG BMU may be observed which remains unchanged for several months. Unspecific bone marrow reactions after PCT may be associated with increased leucocyte blood levels and play a role in the changed systemic glucose BMU. In addition, pretreatment with G-CSF shows an intense amplitifcation of BMU. (orig.)

Analytical evaluation of the novel Lumipulse G BRAHMS procalcitonin immunoassay

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Orazio Ruzzenente

2016-12-01

Full Text Available Objectives: This study was designed to evaluate the analytical performance of the novel Lumipulse G1200 BRAHMS procalcitonin (PCT immunoassay. Design and methods: This analytical evaluation encompassed the calculation of the limit of blank (LOB, limit of detection (LOD, functional sensitivity, intra- and inter-assay imprecision, confirmation of linearity and a comparison with the Vidas BRAHMS PCT assay. Results: The LOB, LOD and functional sensitivity were 0.0010 ng/mL, 0.0016 ng/mL and 0.008 ng/mL, respectively. The total analytical imprecision was found to be 2.1% and the linearity was excellent (r=1.00 in the range of concentrations between 0.006–75.5 ng/mL. The correlation coefficient with Vidas BRAHMS PCT was 0.995 and the equation of the Passing and Bablok regression analysis was [Lumipulse G BRAHMS PCT]=0.76×[Vidas BRAHMS PCT]+0.04. The mean overall bias of Lumipulse G BRAHMS PCT versus Vidas BRAHMS PCT was −3.03 ng/mL (95% confidence interval [CI]: −4.32 to −1.74 ng/mL, whereas the mean bias in samples with PCT concentration between 0–10 ng/mL was −0.49 ng/mL (95% CI: −0.77 to −0.24 ng/mL. The diagnostic agreement was 100% at 0.5 ng/mL, 97% at 2.0 ng/mL and 95% at 10 ng/mL, respectively. Conclusions: These results attest that Lumipulse G BRAHMS PCT exhibits excellent analytical performance, among the best of the methods currently available on the diagnostic market. However, the significant bias compared to the Vidas BRAHMS PCT suggests that the methods cannot be used interchangeably. Keywords: Sepsis, Infection, Procalcitonin, Immunoassay

Porfiria cutánea tarda: asociación con mutaciones HFE, hepatitis virales, alcohol y otros factores de riesgo en Guipúzcoa, País Vasco Porphyria cutanea tarda: An analysis of HFE gene mutations, hepatitis viruses, alcohol intake, and other risk factors in 54 patients from Guipúzcoa, Basque Country, Spain

Directory of Open Access Journals (Sweden)

A. Castiella

2008-12-01

Full Text Available Objetivo: estudiar la frecuencia de las mutaciones en el gen HFE (C282Y, H63D, S65C en un grupo de 54 pacientes con porfiria cutánea tarda (PCT y en un grupo de controles sanos (donantes de sangre en Guipúzcoa. También analizar su relación con los virus de la hepatitis B y C (VHB, VHC, alcohol y otros factores de riesgo reconocidos. Métodos: el análisis de las mutaciones se hizo mediante PCR. Se compararon las frecuencias alélicas y genotípicas. Se determinaron la probabilidad y el test de Chi cuadrado. Resultados: no encontramos asociación entre C282Y y PCT (5,76 vs. 5% controles. Se observó una alta frecuencia alélica en la mutación H63D en PCT (34,25%, pero sin ser estadísticamente significativa (controles 29,31%, debido a la alta prevalencia de esta mutación en la población vasca. La mutación S65C fue menor en PCT que en controles. Encontramos una idéntica presencia de H63D en heterocigosis en ambos grupos (38,8 vs. 38,8%. La asociación con el VHC se objetivó en el 35,18% de los pacientes y la infección por VHB en el 7,4%. Un 55,55% de los pacientes tenía un hábito alcohólico de más de 60 g etanol día. Todos eran negativos para el virus de la inmunodeficiencia humana (VIH y 1 de las 5 mujeres con PCT tomaba estrógenos. Conclusión: las mutaciones C282Y y H63D no tienen un papel relevante en los pacientes con PCT en Guipúzcoa. Los factores externos (consumo importante de alcohol y VHC parecen jugar un papel fundamental en el desarrollo de la PCT en nuestra población.Aim: to study the frequency of HFE gene mutations (C282Y, H63D, S65C in a group of 54 sporadic PCT patients and in a group of healthy controls (blood donors from Guipúzcoa, Spain. We studied the association of PCT with HCV, HBV, alcohol abuse, and other established risk factors. Methods: the analysis of mutations was made by PCR. Allelic and genotypic frequencies were compared. Probability was determined and a Chi-squared test was performed. Results

Optimization of Proton CT Detector System and Image Reconstruction Algorithm for On-Line Proton Therapy.

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Chae Young Lee

Full Text Available The purposes of this study were to optimize a proton computed tomography system (pCT for proton range verification and to confirm the pCT image reconstruction algorithm based on projection images generated with optimized parameters. For this purpose, we developed a new pCT scanner using the Geometry and Tracking (GEANT 4.9.6 simulation toolkit. GEANT4 simulations were performed to optimize the geometric parameters representing the detector thickness and the distance between the detectors for pCT. The system consisted of four silicon strip detectors for particle tracking and a calorimeter to measure the residual energies of the individual protons. The optimized pCT system design was then adjusted to ensure that the solution to a CS-based convex optimization problem would converge to yield the desired pCT images after a reasonable number of iterative corrections. In particular, we used a total variation-based formulation that has been useful in exploiting prior knowledge about the minimal variations of proton attenuation characteristics in the human body. Examinations performed using our CS algorithm showed that high-quality pCT images could be reconstructed using sets of 72 projections within 20 iterations and without any streaks or noise, which can be caused by under-sampling and proton starvation. Moreover, the images yielded by this CS algorithm were found to be of higher quality than those obtained using other reconstruction algorithms. The optimized pCT scanner system demonstrated the potential to perform high-quality pCT during on-line image-guided proton therapy, without increasing the imaging dose, by applying our CS based proton CT reconstruction algorithm. Further, we make our optimized detector system and CS-based proton CT reconstruction algorithm potentially useful in on-line proton therapy.

High-permeability region size on perfusion CT predicts hemorrhagic transformation after intravenous thrombolysis in stroke.

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Josep Puig

Full Text Available Blood-brain barrier (BBB permeability has been proposed as a predictor of hemorrhagic transformation (HT after tissue plasminogen activator (tPA administration; however, the reliability of perfusion computed tomography (PCT permeability imaging for predicting HT is uncertain. We aimed to determine the performance of high-permeability region size on PCT (HPrs-PCT in predicting HT after intravenous tPA administration in patients with acute stroke.We performed a multimodal CT protocol (non-contrast CT, PCT, CT angiography to prospectively study patients with middle cerebral artery occlusion treated with tPA within 4.5 hours of symptom onset. HT was graded at 24 hours using the European-Australasian Acute Stroke Study II criteria. ROC curves selected optimal volume threshold, and multivariate logistic regression analysis identified predictors of HT.The study included 156 patients (50% male, median age 75.5 years. Thirty-seven (23,7% developed HT [12 (7,7%, parenchymal hematoma type 2 (PH-2]. At admission, patients with HT had lower platelet values, higher NIHSS scores, increased ischemic lesion volumes, larger HPrs-PCT, and poorer collateral status. The negative predictive value of HPrs-PCT at a threshold of 7mL/100g/min was 0.84 for HT and 0.93 for PH-2. The multiple regression analysis selected HPrs-PCT at 7mL/100g/min combined with platelets and baseline NIHSS score as the best model for predicting HT (AUC 0.77. HPrs-PCT at 7mL/100g/min was the only independent predictor of PH-2 (OR 1, AUC 0.68, p = 0.045.HPrs-PCT can help predict HT after tPA, and is particularly useful in identifying patients at low risk of developing HT.

High-permeability region size on perfusion CT predicts hemorrhagic transformation after intravenous thrombolysis in stroke

Science.gov (United States)

Puig, Josep; Blasco, Gerard; Daunis-i-Estadella, Pepus; van Eendendburg, Cecile; Carrillo-García, María; Aboud, Carlos; Hernández-Pérez, María; Serena, Joaquín; Biarnés, Carles; Nael, Kambiz; Liebeskind, David S.; Thomalla, Götz; Menon, Bijoy K.; Demchuk, Andrew; Wintermark, Max; Pedraza, Salvador

2017-01-01

Objective Blood-brain barrier (BBB) permeability has been proposed as a predictor of hemorrhagic transformation (HT) after tissue plasminogen activator (tPA) administration; however, the reliability of perfusion computed tomography (PCT) permeability imaging for predicting HT is uncertain. We aimed to determine the performance of high-permeability region size on PCT (HPrs-PCT) in predicting HT after intravenous tPA administration in patients with acute stroke. Methods We performed a multimodal CT protocol (non-contrast CT, PCT, CT angiography) to prospectively study patients with middle cerebral artery occlusion treated with tPA within 4.5 hours of symptom onset. HT was graded at 24 hours using the European-Australasian Acute Stroke Study II criteria. ROC curves selected optimal volume threshold, and multivariate logistic regression analysis identified predictors of HT. Results The study included 156 patients (50% male, median age 75.5 years). Thirty-seven (23,7%) developed HT [12 (7,7%), parenchymal hematoma type 2 (PH-2)]. At admission, patients with HT had lower platelet values, higher NIHSS scores, increased ischemic lesion volumes, larger HPrs-PCT, and poorer collateral status. The negative predictive value of HPrs-PCT at a threshold of 7mL/100g/min was 0.84 for HT and 0.93 for PH-2. The multiple regression analysis selected HPrs-PCT at 7mL/100g/min combined with platelets and baseline NIHSS score as the best model for predicting HT (AUC 0.77). HPrs-PCT at 7mL/100g/min was the only independent predictor of PH-2 (OR 1, AUC 0.68, p = 0.045). Conclusions HPrs-PCT can help predict HT after tPA, and is particularly useful in identifying patients at low risk of developing HT. PMID:29182658

Product consistency leach tests of Savannah River Site radioactive waste glasses

International Nuclear Information System (INIS)

Bibler, N.E.; Bates, J.K.

1989-01-01

The Product Consistency Test (PCT) is a glass leach test that was developed at the Savannah River Site (SRS) to routinely confirm the durability of nuclear waste glasses that will be produced in the Defense Waste Processing Facility. The PCT is a 7 day, crushed glass leach test in deionized water at 90 degree C. Final leachates are filtered and acidified prior to analysis. To demonstrate the reproducibility of the PCT when performed remotely, SRS and Argonne National Laboratory have performed the PCT on samples of two radioactive glasses. The tests were also performed to compare the releases of the radionuclides with the major nonradioactive glass components and to determine if radiation from the glass was affecting the results of the PCT. The test was performed in triplicate at each laboratory. For the major soluble elements, B, Li, Na, and Si, in the glass, each investigator obtained relative precisions in the range 2--5% in the triplicate tests. This range indicates good precision for the PCT when performed remotely with master slave manipulators in a shielded cell environment

Platelet Count and Plateletcrit

African Journals Online (AJOL)

strated that neonates with late onset sepsis (bacteremia after 3 days of age) had a dramatic increase in MPV and. PDW18. We hypothesize that as the MPV and PDW increase and platelet count and PCT decrease in sick children, intui- tively, the ratio of MPV to PCT; MPV to Platelet count,. PDW to PCT, PDW to platelet ...

Can procalcitonin reduce unnecessary voiding cystoureterography in children with first febrile urinary tract infection?

Science.gov (United States)

Halimi-Asl, Aliasghar; Hosseini, Amir Hossein; Nabavizadeh, Pooneh

2014-08-01

Recently, new predictors of vesicoureteral reflux (VUR) in children with a first febrile UTI such as Procalcitonin (PCT) were introduced as selective approaches for cystography. This study wants to show the capability of PCT in predicting presence of VUR at the first febrile UTI in children. Patients between 1 month and 15 years of age with febrile UTI were included in this prospective study. PCT values were measured through a semi-quantitative method in four grades comprising values less than 0.5, 0.5-2.0, 2.0-10.0 and above 10.0 ng/ml. The independence of PCT levels in predicting VUR were assessed after adjustment for all potential confounders using a logistic-regression model. A total of 68 patients, 54 (79.4%) girls and 14 (20.6%) boys were evaluated. PCT level demonstrated a significant difference between patients with positive VUR and those with negative VUR (P=0.012). To calculate the independent factors that may predict the presence of VUR, all included variables were adjusted for age and sex. Results of logistic regression showed that a PCT level between 2.0 and 10.0 ng/mL could independently predict presence of VUR (Odds ratio=6.11, CI 95%= 1.22-30.77, P=0.03). Our finding in this study showed that readily available semi-quantitative measures for PCT are feasible for detecting patients with VUR. We suggest that in semi-quantitative measurements of PCT, levels between 2.0 and 10.0 ng/ml could be an independent predictor of positive VUR.

3F og alle de andre

DEFF Research Database (Denmark)

Due, Jesper Jørgen; Madsen, Jørgen Steen

Spørgsmålene stiller sig i kø, når man skal prøve at forklare den helt ekstraordinære forskel, der er på stemmeafgivningen om mæglingsforslaget i 3F sammenlignet med alle de øvrige omfattede LO-forbund. Det kan være svært at forstå, at 62 pct. af 3F's medlemmer, der deltog i afstemningen, vendte...... tommelfingeren ned, mens eksempelvis 66 pct. af Metals medlemmer, 65 pct. af TIB's medlemmer og 78 pct. af HK's medlemmer stemte ja til det samlede resultat af OK 2007....

Grain refining of Al-4.5Cu alloy by adding an Al-30TiC master alloy

Energy Technology Data Exchange (ETDEWEB)

Sato, Kazuaki [Toyota Motor Corp., Shizuoka (Japan). Materials Engineering Div. III; Flemings, M.C. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science and Engineering

1998-06-01

A particulate Al-30 wt pct TiC composite was employed as a grain refiner for the Al-4.5 wt pct Cu alloy. The composite contains submicron TiC particles. The addition of the TiC grain refiner to the metal alloy in the amount of 0.1 Ti wt pct effected a remarkable reduction in the average grain size in Al-4.5 wt pct Cu alloy castings. With the content of over 0.2 Ti wt pct, the grain refiner maintained its refining effectiveness even after a 3,600-second holding time at 973 K. The TiC particles in the resulting castings were free of interfacial phases. It is concluded that the TiC are the nucleating agents and that they are resistant to the fading effect encountered with most grain refiners.

Mutaciones del gen de la Hemocromatosis en donantes de sangre voluntarios y en pacientes con Porfiria cutánea tarda en Chile Mutations of hemochromatosis gene in volunteer blood donors and Chilean porphyria cutanea tarda patients

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Carlos Wolff F

2006-10-01

Full Text Available La acumulación de hierro hepático asociada a mutaciones en el gen HFE de la hemocromatosis hereditaria (HH en los pacientes con porfiria cutánea tarda (PCT podría tener un papel en la etiología y en la expresión clínica de esta enfermedad. Se estudió la frecuencia de las mutaciones H63D y C282Y en un grupo de pacientes con PCT y se la comparó con la observada en un grupo de donantes voluntarios de sangre. Los pacientes con PCT fueron catalogados como portadores de la forma hereditaria o adquirida de la enfermedad, según presentaran o no mutaciones en el gen uroporfirinógeno decarboxilasa (UROD. El 50% de los pacientes con PCT eran portadores de la forma genética de la enfermedad, porcentaje significativamente mayor que lo informado en otras series. El 23% de los donantes voluntarios de sangre eran portadores de la mutación H63D y 2.4% lo era de la mutación C282Y. Frecuencias similares a lo encontrado por otros autores en población chilena de etnia blanca, en población argentina y española, pero significativamente más alta que lo encontrado en estudios en población aborigen araucana. Esto tiene, probablemente, relación con el predominio de ascendencia española en la población blanca chilena. La frecuencia de mutación en el gen HFE en pacientes con PCT no fue significativamente diferente que la observada en donantes voluntarios de sangre. Tampoco hubo diferencias significativas en la frecuencia de estas mutaciones entre los casos con PCT adquirida respecto de aquellos en que ésta era de origen genético. Los resultados obtenidos no permiten afirmar que exista asociación entre la PCT y la condición de portador de mutaciones del gen HFE de la hemocromatosis hereditaria.In patients with porphyria cutanea tarda (PCT, hepatic iron accumulation associated to hereditary hemochromatosis (HH could play a role in the etiology and in the clinical expression of the disease. The H63D and C282Y mutations of the HFE gene frequency were

Modified heat treatment for lower temperature improvement of the mechanical properties of two ultrahigh strength low alloy steels

Science.gov (United States)

Tomita, Yoshiyuki; Okabayashi, Kunio

1985-01-01

In the previous papers, a new heat treatment for improving the lower temperature mechanical propertise of the ultrahigh strength low alloy steels was suggested by the authors which produces a mixed structure of 25 vol pct lower bainite and 75 vol pct martensite through isothermal transformation at 593 K for a short time followed by water quenching (after austenitization at 1133 K). In this paper, two commercial Japanese ultrahigh strength steels, 0.40 pct C-Ni-Cr-Mo (AISI 4340 type) and 0.40 pct C-Cr-Mo (AISI 4140 type), have been studied to determine the effect of the modified heat treatment, coupled above new heat treatment with γ ⇆ α' repctitive heat treatment, on the mechanical properties from ambient temperature (287 K) to 123 K. The results obtained for various test temperatures have been compared with those for the new heat treatment reported previously and the conventional 1133 K direct water quenching treatment. The incorporation of intermediate four cyclic γ ⇆ α' repctitive heat treatment steps (after the initial austenitization at 1133 K and oil quenching) into the new heat treatment reported previously, as compared with the conventional 1133 K direct water quenching treatment, significantly improved 0.2 pct proof stress as well as notch toughness of the 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel at similar fracture ductility levels from 287 to 123 K. Also, this heat treatment, as compared with the conventional 1133 K direct water quenching treatment, significantly improved both 0.2 pct proof stress and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel with increased fracture ductility at 203 K and above. The microstructure consists of mixed areas of ultrafine grained martensite, within which is the refined blocky, highly dislocated structure, and the second phase lower bainite (about 15 vol pct), which appears in acicular form and partitions prior austenite grains. This newly developed heat treatment makes it possible to modify

PROCALCITONIN AND INTERLEUKIN-6 AS MARKERS OF SEVERE INFECTION IN CHILDREN WITH FEBRILE NEUTROPENIA

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Lidija Kitanovski

2004-12-01

Full Text Available Background. The results of the study conducted to determine whether procalcitonin (PCT and interleukin-6 (IL-6 are more sensitive and specific markers of severe infection in children with febrile neutropenia (FN than routinelly used C-reactive protein (CRP are presented in the article. 68 episodes of FN experienced by 32 patients were divided into three groups according to the site of infection. Group 1: episodes of bacteraemia and/or clinical sepsis (n = 16, group 2: episodes of focal infection (n = 16 and group 3: episodes of fever of unknown origin (FUO (n = 36. Blood samples for further PCT and IL-6 determination were collected on three consecutive days. CRP concentrations were measured daily in each patient until the resolution of fever. PCT, IL-6 and CRP concentrations were measured on one occassion in each of the 18 afebrile patients with malignant disase forming the reference group. Serum PCT and IL-6 concentrations were measured by immunochemiluminometric and immunoenzymatic assay. Receiver Operating Characteristic (ROC curves were used to determine optimum sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of the studied parameters.Conclusions. PCT and IL-6 were found to be earlier and more sensitive markers of severe infection in neutropenic patients than CRP. The erliest one was IL-6, followed by PCT and CRP. Sequential determination of PCT up to 72 hours improved its diagnostic value, which was not the case for IL-6.In patients with gramnegative bacteraemias PCT concentracions were 3–5 times higher comparing to grampositive, whereas IL-6 concentrations were comparable in both groups.

Role of procalcitonin in infected diabetic foot ulcer.

Science.gov (United States)

Park, Jung Ho; Suh, Dong Hun; Kim, Hak Jun; Lee, Yong In; Kwak, Il Hoon; Choi, Gi Won

2017-06-01

Procalcitonin (PCT) has been recently accepted as a marker for diagnosing infection. The aim of the present study was to determine whether PCT levels are associated with infection severity of diabetic foot ulcers and whether PCT levels would be helpful to differentiate infected diabetic foot ulcer (IDFU) from IDFU associated with other infectious diseases (IDFU+O). We prospectively included 123 diabetic patients hospitalized for IDFU. Infection severity of diabetic foot ulcers was graded according to the Infectious Diseases Society of America-International Working Group on the Diabetic Foot clinical classification of diabetic foot infection. Chest radiograph, urinalysis, urine microscopy, urine culture, and blood cultures (if fever was present) were performed for all patients to diagnose other infectious diseases. Laboratory parameters were measured from blood venous samples. PCT (Spearman's ρ=0.338, Pdiabetic foot ulcers. However, only PCT levels could differentiate patients with associated infectious diseases from patients with no concomitant infection (area under the receiver-operator characteristic curve 0.869, Pdiabetic foot ulcers and PCT levels>0.59ng/mL in patients with IDFU may be associated with other systemic bacterial infection. Copyright © 2017 Elsevier B.V. All rights reserved.

Role of procalcitonin in predicting dilating vesicoureteral reflux in young children hospitalized with a first febrile urinary tract infection.

Science.gov (United States)

Sun, Hai-Lun; Wu, Kang-Hsi; Chen, Shan-Ming; Chao, Yu-Hua; Ku, Min-Sho; Hung, Tong-Wei; Liao, Pen-Fen; Lue, Ko-Huang; Sheu, Ji-Nan

2013-09-01

The aim of this article was to assess the usefulness of procalcitonin (PCT) as a marker for predicting dilating (grades III-V) vesicoureteral reflux (VUR) in young children with a first febrile urinary tract infection. Children ≤2 years of age with a first febrile urinary tract infection were prospectively evaluated. Serum samples were tested for PCT at the time of admission to a tertiary hospital. All children underwent renal ultrasonography (US), Tc-dimercaptosuccinic acid renal scan, and voiding cystourethrography. The diagnostic characteristics of PCT test for acute pyelonephritis and dilating VUR were calculated. Of 272 children analyzed (168 boys and 104 girls; median age, 5 months), 169 (62.1%) had acute pyelonephritis. There was VUR demonstrated in 97 (35.7%), including 70 (25.7%) with dilating VUR. The median PCT value was significantly higher in children with VUR than in those without (P predictors of dilating VUR. PCT is useful for diagnosing acute pyelonephritis and predicting dilating VUR in young children with a first febrile urinary tract infection. A voiding cystourethrography is indicated only in children with high PCT values (≥1.0 ng/mL) and/or abnormalities found on a US.

Porphyria Cutanea Tarda Presenting with Scleroderma, Ichthyosis, Alopecia, and Vitiligo

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Megan E. MacGillivray

2018-05-01

Full Text Available Porphyria cutanea tarda (PCT is a cutaneous porphyria that presents later in life with cutaneous findings in sun-exposed sites. We report a complex case of PCT in a 67-year-old woman with an unusual constellation of cutaneous findings: scleroderma, acquired ichthyosis, and nonscarring alopecia. Possible triggers for her PCT include tamoxifen treatment for breast cancer and carrier status of the hemochromatosis gene. High-dose chloroquine was used to successfully achieve clinical remission and normalize her uroporphyrins. While on chloroquine she developed extensive classic vitiligo. It is not clear if this is another feature of her complex and unusual PCT, or a consequence of her antimalarial therapy.

HOME COST Pct Units by Rent as Pct of HH Income in 1999 NMSD 2000

Data.gov (United States)

Earth Data Analysis Center, University of New Mexico — The 2006 Second Edition TIGER/Line files are an extract of selected geographic and cartographic information from the Census TIGER database. The geographic coverage...

HOME COST Pct All OwnerOcc Units Costs as Pct 1999 HH Income NMHD 2000

Data.gov (United States)

Earth Data Analysis Center, University of New Mexico — The 2006 Second Edition TIGER/Line files are an extract of selected geographic and cartographic information from the Census TIGER database. The geographic coverage...

Recovery and Precipitate Analysis of 9 Pct Cr-1 Pct MoVNb Steel during Creep

NARCIS (Netherlands)

Kabadwal, A.; Tamura, M.; Shinozuka, K.; Esaka, H.

The effect of tempering temperature and creep exposure on the microstructure of a modified 9Cr steel was investigated. Creep-interrupted specimens, including the grip portion, were investigated precisely using mainly X-ray and inductively coupled plasma (ICP) spectroscopy. After saturation of

Microstructural and Texture Development in Two Austenitic Steels with High-Manganese Content

DEFF Research Database (Denmark)

Bhattacharya, Basudev; Ray, Ranjit Kumar; Leffers, Torben

2015-01-01

Two austenitic steels, Fe-21.3Mn-3.44Si-3.74Al-0.5C and Fe-29.8Mn-2.96Si-2.73Al-0.52C, were subjected to cold rolling with 30 to 80 pct reduction with an increment of 10 pct and subsequently the development of their microstructures and textures were studied. The overall texture after 80 pct cold ...

Intraocular pressure change over a habitual 24-hour period after changing posture or drinking water and related factors in normal tension glaucoma.

Science.gov (United States)

Sakata, Rei; Aihara, Makoto; Murata, Hiroshi; Saito, Hitomi; Iwase, Aiko; Yasuda, Noriko; Araie, Makoto

2013-08-07

We investigated the correlation between 24-hour IOP in the habitual (sitting during day and supine during night) position (H24h-IOP) and IOP after a postural-change test (PCT-IOP) and a water-drinking test (WDT-IOP). We also investigated ocular and systemic factors related with them in patients with normal tension glaucoma (NTG). Japanese NTG patients underwent H24h-IOP, PCT-IOP, and WDT-IOP measurements during a 24-hour period. Correlations among H24h-IOP, PCT-IOP, and WDT-IOP, and contributing ocular/systemic factors were investigated using regression analysis. There were 33 patients included. Peak H24h-IOP correlated positively with peak PCT-IOP and peak WDT-IOP (estimate = 0.422 and 0.419, P ≤ 0.010), and peak PCT-IOP with WDT-IOP (0.44, P = 0.002). Peak H24h-IOP correlated with refraction (0.36, P = 0.048) and negatively with the mean deviation (MD, -0.066, P = 0.031). MD and baseline IOP (the mean of H24h-IOP) correlated negatively with the H24h-IOP fluctuation (-0.058 and -0.58, P ≤ 0.050). Refraction, baseline IOP, mean blood pressure (mBP), and body mass index (BMI) correlated with peak PCT-IOP (0.23, 0.52, 0.097, and 0.32, respectively, P ≤ 0.038). PCT-IOP difference correlated with refraction and mBP (0.31 and 0.093, P ≤ 0.016) and negatively with age (-0.069, P = 0.003). Central corneal thickness, baseline IOP, age, and BMI correlated with peak WDT-IOP (0.030, 0.40, 0.088, and 0.26, P ≤ 0.050). Age and BMI correlated with WDT-IOP difference (0.086 and 0.20, P < 0.032). Positive correlation was found among the peaks of H24h-, PCT-, and WDT-IOP. A worse visual field was associated with higher peak and greater fluctuation of H24h-IOP in NTG. Several ocular/systemic factors were important in interpreting H24h-, PCT-, and WDT-IOP.

SU-D-BRD-03: Improving Plan Quality with Automation of Treatment Plan Checks

International Nuclear Information System (INIS)

Covington, E; Younge, K; Chen, X; Lee, C; Matuszak, M; Kessler, M; Acosta, E; Orow, A; Filpansick, S; Moran, J; Keranen, W

2015-01-01

Purpose: To evaluate the effectiveness of an automated plan check tool to improve first-time plan quality as well as standardize and document performance of physics plan checks. Methods: The Plan Checker Tool (PCT) uses the Eclipse Scripting API to check and compare data from the treatment planning system (TPS) and treatment management system (TMS). PCT was created to improve first-time plan quality, reduce patient delays, increase efficiency of our electronic workflow, and to standardize and partially automate plan checks in the TPS. A framework was developed which can be configured with different reference values and types of checks. One example is the prescribed dose check where PCT flags the user when the planned dose and the prescribed dose disagree. PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user. A PDF report is created and automatically uploaded into the TMS. Prior to and during PCT development, errors caught during plan checks and also patient delays were tracked in order to prioritize which checks should be automated. The most common and significant errors were determined. Results: Nineteen of 33 checklist items were automated with data extracted with the PCT. These include checks for prescription, reference point and machine scheduling errors which are three of the top six causes of patient delays related to physics and dosimetry. Since the clinical roll-out, no delays have been due to errors that are automatically flagged by the PCT. Development continues to automate the remaining checks. Conclusion: With PCT, 57% of the physics plan checklist has been partially or fully automated. Treatment delays have declined since release of the PCT for clinical use. By tracking delays and errors, we have been able to measure the effectiveness of automating checks and are using this information to prioritize future development. This project was supported in part by P01CA059827

The feasibility of utilizing pseudo CT-data for online MRI based treatment plan adaptation for a stereotactic radiotherapy treatment of spinal bone metastases

International Nuclear Information System (INIS)

Hoogcarspel, Stan J; Van der Velden, Joanne M; Lagendijk, Jan J W; Van Vulpen, Marco; Raaymakers, Bas W

2014-01-01

The purpose of this study was to investigate what pseudo-CT (pCT) strategy is sufficient for online MRI based treatment plan adaptation of a stereotactic treatment for spinal bone metastases. For this purpose, the dosimetric accuracy of five increasingly complex pCT strategies was evaluated using the planning CT data of 20 patients suffering from spinal metastases. For each pCT, a treatment plan was developed and simulated on both the pCT and the original CT data of the patient. The two resulting dose distributions were compared using gamma analysis of 2%/2 mm. In this paper, a Gamma Pass Rate (GPR) of ⩾95% within the Target Volume (TV) was considered clinically acceptable. We additionally demonstrated in this paper the automatic generation of each investigated pCT strategy with the use of dedicated MRI data complemented with pre-treatment CT data of a patient in treatment position. The dosimetric accuracy of a pCT increases when additional bulk densities are utilized for a pCT. However, the dosimetric accuracy of even the most complex ‘bulk density’ pCT strategy used in this study had an average GPR of only 78% within the TV. However, if information on the heterogeneous electron density distribution within the affected vertebral body was available, a clinically acceptable 99% mean GPR was observed. All pCTs could successfully be generated using the MRI data in combination with the CT data of a patient in treatment position. The results presented in this study show that a simple ‘bulk density’ pseudo-CT strategy is not feasible for online MRI based treatment plan adaptation for spinal bone metastases. However, a clinically acceptable result is generated if the information on the heterogeneous electron density (ED) distribution within the affected vertebral bone is available. Therefore, any pCT strategy for this tumor site should include a method which can estimate the heterogeneous ED of the affected vertebral bone. (paper)

SU-D-BRD-03: Improving Plan Quality with Automation of Treatment Plan Checks

Energy Technology Data Exchange (ETDEWEB)

Covington, E; Younge, K; Chen, X; Lee, C; Matuszak, M; Kessler, M; Acosta, E; Orow, A; Filpansick, S; Moran, J [University of Michigan Hospital and Health System, Ann Arbor, MI (United States); Keranen, W [Varian Medical Systems, Palo Alto, CA (United States)

2015-06-15

Purpose: To evaluate the effectiveness of an automated plan check tool to improve first-time plan quality as well as standardize and document performance of physics plan checks. Methods: The Plan Checker Tool (PCT) uses the Eclipse Scripting API to check and compare data from the treatment planning system (TPS) and treatment management system (TMS). PCT was created to improve first-time plan quality, reduce patient delays, increase efficiency of our electronic workflow, and to standardize and partially automate plan checks in the TPS. A framework was developed which can be configured with different reference values and types of checks. One example is the prescribed dose check where PCT flags the user when the planned dose and the prescribed dose disagree. PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user. A PDF report is created and automatically uploaded into the TMS. Prior to and during PCT development, errors caught during plan checks and also patient delays were tracked in order to prioritize which checks should be automated. The most common and significant errors were determined. Results: Nineteen of 33 checklist items were automated with data extracted with the PCT. These include checks for prescription, reference point and machine scheduling errors which are three of the top six causes of patient delays related to physics and dosimetry. Since the clinical roll-out, no delays have been due to errors that are automatically flagged by the PCT. Development continues to automate the remaining checks. Conclusion: With PCT, 57% of the physics plan checklist has been partially or fully automated. Treatment delays have declined since release of the PCT for clinical use. By tracking delays and errors, we have been able to measure the effectiveness of automating checks and are using this information to prioritize future development. This project was supported in part by P01CA059827.

Improving treatment plan evaluation with automation

Science.gov (United States)

Covington, Elizabeth L.; Chen, Xiaoping; Younge, Kelly C.; Lee, Choonik; Matuszak, Martha M.; Kessler, Marc L.; Keranen, Wayne; Acosta, Eduardo; Dougherty, Ashley M.; Filpansick, Stephanie E.

2016-01-01

The goal of this work is to evaluate the effectiveness of Plan‐Checker Tool (PCT) which was created to improve first‐time plan quality, reduce patient delays, increase the efficiency of our electronic workflow, and standardize and automate the physics plan review in the treatment planning system (TPS). PCT uses an application programming interface to check and compare data from the TPS and treatment management system (TMS). PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user as part of a plan readiness check for treatment. Prior to and during PCT development, errors identified during the physics review and causes of patient treatment start delays were tracked to prioritize which checks should be automated. Nineteen of 33 checklist items were automated, with data extracted with PCT. There was a 60% reduction in the number of patient delays in the six months after PCT release. PCT was successfully implemented for use on all external beam treatment plans in our clinic. While the number of errors found during the physics check did not decrease, automation of checks increased visibility of errors during the physics check, which led to decreased patient delays. The methods used here can be applied to any TMS and TPS that allows queries of the database. PACS number(s): 87.55.‐x, 87.55.N‐, 87.55.Qr, 87.55.tm, 89.20.Bb PMID:27929478

Procalcitonin as a biomarker for severe Plasmodium falciparum disease: a critical appraisal of a semi-quantitative point-of-care test in a cohort of travellers with imported malaria.

Science.gov (United States)

Hesselink, Dennis A; Burgerhart, Jan-Steven; Bosmans-Timmerarends, Hanna; Petit, Pieter; van Genderen, Perry J J

2009-09-01

Imported malaria occurs as a relatively rare event in developed countries. As a consequence, most clinicians have little experience in making clinical assessments of disease severity and decisions regarding the need for parenteral therapy or high-level monitoring. In this study, the diagnostic accuracy of procalcitonin (PCT) for severe Plasmodium falciparum disease was assessed in a cohort of 100 consecutive travellers with various species of imported malaria. In all patients, PCT was measured on admission with a semi-quantitative 'point-of-care' test. Patients with severe P. falciparum malaria had significantly higher median PCT levels on admission as compared with patients with uncomplicated P. falciparum disease. In addition, PCT levels in patients with non-falciparum malaria were also higher compared with patients with non-severe falciparum malaria but lower compared with severe P. falciparum malaria. At a cut-off point of 10 ng/mL, PCT had a sensitivity of 0,67 and a specificity of 0,94 for severe falciparum disease. However, at lower cut-off points the specificity and positive predictive value were rather poor although the sensitivity and negative predictive value remained high. Potential drawbacks in the interpretation of elevated PCT levels on admission may be caused by infections with non-falciparum species and by concomitant bacterial infections. Semi-quantitative determination of PCT on admission is of limited use in the initial clinical assessment of disease severity in travellers with imported malaria, especially in settings with limited experience with the treatment of malaria.

Procalcitonin levels in bloodstream infections caused by different sources and species of bacteria.

Science.gov (United States)

Yan, Sheng Tao; Sun, Li Chao; Jia, Hong Bing; Gao, Wen; Yang, Jian Ping; Zhang, Guo Qiang

2017-04-01

The aim of this study was to evaluate procalcitonin (PCT) diagnostic accuracy in discriminating gram-negative (GN) from gram-positive (GP) bloodstream infections and determining the relationship between PCT levels, infection sites, and pathogen types. Clinical and laboratory data were collected from patients with blood culture (BC)-positive sepsis between January 2014 and December 2015. PCT levels at different infection sites were compared, as was the presence of GN and GP bloodstream infection. A receiver operating characteristic (ROC) curve was generated to assess diagnostic accuracy. Of the 486 monomicrobial BCs, 254 (52.26%) were positive for GN bacteria (GNB), and 202 (42.18%) for GP bacteria (GPB). Median PCT levels were higher in BCs positive for GN (2.42ng/ml, IQR: 0.38-15.52) than in those positive for GPB (0.49ng/ml, IQR: 0.13-5.89) (PAcinetobacter baumanni/Burkholderia cepacia, Klebsiella pneumonia and Acinetobacter baumanni. PCT levels caused by GPB differed between Staphylococcus epidermidis/Staphylococcus aureus and Staphylococcus hominis/Staphylococcus haemolyticus, Enterococcus faecium and Enterococcus faecalis/S.hominis/S. haemolyticus. Among patients with known infection sites, there were statistical differences in PCT levels between abdominal infection and pneumonia/infective endocarditis, urinary tract infection and pneumonia/catheter-related infection/infective endocarditis. PCT can distinguish between GNB and GPB infection, as well as between different bacterial species and infection sites. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Streamlining antibiotic therapy with procalcitonin protocols: consensus and controversies.

Science.gov (United States)

Haubitz, Sebastian; Mueller, Beat; Schuetz, Philipp

2013-04-01

Accumulating evidence supports procalcitonin (PCT) as an accurate surrogate biomarker for likelihood and severity of bacterial infections. In community-acquired pneumonia and other respiratory infections, PCT-guided antibiotic therapy algorithms resulted in reduced antibiotic exposure while maintaining a similar or even better level of safety compared with standard care. Reductions in antibiotic use translate into lower treatment costs, decreased risk of side effects and decreased bacterial multiresistance. This is especially important, as acute respiratory infections represent the most frequent reason for antibiotic prescriptions worldwide. Still, there is some controversy about the benefits of PCT measurement in sepsis patients in the intensive care unit and for nonrespiratory infections. Highly sensitive PCT assays are readily available in many hospitals today, and point-of-care assays with high enough sensitivity for antibiotic guidance are expected to be available soon. Herein, the authors provide an overview of recent studies evaluating PCT in different clinical situations and an outlook of currently enrolling or upcoming interventional trials.

Illness Perception and Psychological Distress in Persons with Porphyria Cutanea Tarda.

Science.gov (United States)

Andersen, Janice; Nordin, Karin; Sandberg, Sverre

2016-06-15

Porphyria cutanea tarda (PCT) requires long-term treatment and follow-up, although many patients experience life-long remission. The aim of this cross-sectional postal survey was to describe and investigate the association between illness perception, health complaints, self-reported symptoms and distress in persons with PCT. The participants perceived PCT as a chronic condition with high levels of personal and treatment control. Persons who reported active symptoms scored higher on perceived illness threat, total health complaints and psychological distress compared with those in remission or latent phases. However, a higher perception of illness threat and the total burden of health complaints were more closely associated with psychological distress than were perceived PCT symptoms activity. This has implications for clinical consultation; dermatologists should be attentive to symptoms activity, but also recognize that patients in remission with a high perceived illness threat and multiple health complaints might be especially vulnerable to psychological distress with regards to PCT.

The Take Control Course: Conceptual rationale for the development of a transdiagnostic group for common mental health problems

Directory of Open Access Journals (Sweden)

Lydia eMorris

2016-02-01

Full Text Available Background: Increasingly, research supports the utility of a transdiagnostic understanding of psychopathology. However, there is no consensus regarding the theoretical approach that best explains this. Transdiagnostic interventions can offer service delivery advantages; this is explored in the current review, focusing on group modalities and primary care settings. Objective: This review seeks to explore whether a Perceptual Control Theory (PCT explanation of psychopathology across disorders is a valid one. Further, this review illustrates the process of developing a novel transdiagnostic intervention (Take Control Course; TCC from a PCT theory of functioning.Method: Narrative review.Results and Conclusions: Considerable evidence supports key tenets of PCT. Further, PCT offers a novel perspective regarding the mechanisms by which a number of familiar techniques, such as exposure and awareness, are effective. However, additional research is required to directly test the relative contribution of some PCT mechanisms predicted to underlie psychopathology. Directions for future research are considered.

Hemochromatosis (HFE) gene mutations and response to chloroquine in porphyria cutanea tarda.

Science.gov (United States)

Stölzel, Ulrich; Köstler, Erich; Schuppan, Detlef; Richter, Matthias; Wollina, Uwe; Doss, Manfred O; Wittekind, Christian; Tannapfel, Andrea

2003-03-01

To examine the role of hemochromatosis (HFE) gene mutations, which are associated with porphyria cutanea tarda (PCT), in the therapeutic response to chloroquine. We retrospectively analyzed a database (Excel version 2001 [Microsoft Excel, Redmond, Wash]; date range of search, 1985-1999) of chloroquine-treated patients with PCT on whether HFE mutations (C282Y and H63D) might have influenced the clinical response, urinary porphyrin excretion, liver enzyme activities, and serum iron markers. Serum samples and corresponding complete sets of data before and after therapy were available in 62 of 207 patients with PCT who were treated exclusively with chloroquine. Academic teaching hospital. For treatment, low-dose chloroquine diphosphate, 125 to 250 mg twice weekly, was used during a median time of 16 months (range, 12-26 months). Of the 62 German patients with PCT, 37 (60%) carries HFE mutations. Chloroquine therapy was accompanied by clinical remission and reduced urinary porphyrin excretion (P<.001) in the 24 patients (39%) with HFE wild type as well as in 35 HFE heterozygous patients with PCT (56%). Decreases of serum iron markers following chloroquine therapy were limited to patients with PCT and HFE wild type. All patients homozygous for the C282Y mutation (3 [5%] of 62) had high serum iron, ferritin, and transferrin saturation and failed to respond to chloroquine treatment. The therapeutic response to chloroquine was not compromised by C282Y heterozygosity and compound heterozygosity of HFE mutations. Because HFE C282Y homozygotes (+/+) did not respond to chloroquine and a decrease in serum iron concentration was limited to patients with PCT and HFE wild type, phlebotomy should be first-line therapy in patients with PCT and HFE mutations.

Monitoring procalcitonin in febrile neutropenia: what is its utility for initial diagnosis of infection and reassessment in persistent fever?

Directory of Open Access Journals (Sweden)

James Owen Robinson

Full Text Available BACKGROUND: Management of febrile neutropenic episodes (FE is challenged by lacking microbiological and clinical documentation of infection. We aimed at evaluating the utility of monitoring blood procalcitonin (PCT in FE for initial diagnosis of infection and reassessment in persistent fever. METHODS: PCT kinetics was prospectively monitored in 194 consecutive FE (1771 blood samples: 65 microbiologically documented infections (MDI, 33.5%; 49 due to non-coagulase-negative staphylococci, non-CNS, 68 clinically documented infections (CDI, 35%; 39 deep-seated, and 61 fever of unexplained origin (FUO, 31.5%. RESULTS: At fever onset median PCT was 190 pg/mL (range 30-26'800, without significant difference among MDI, CDI and FUO. PCT peak occurred on day 2 after onset of fever: non-CNS-MDI/deep-seated-CDI (656, 80-86350 vs. FUO (205, 33-771; p500 pg/mL distinguished non-CNS-MDI/deep-seated-CDI from FUO with 56% sensitivity and 90% specificity. PCT was >500 pg/ml in only 10% of FUO (688, 570-771. A PCT peak >500 pg/mL (1196, 524-11950 occurred beyond 3 days of persistent fever in 17/21 (81% invasive fungal diseases (IFD. This late PCT peak identified IFD with 81% sensitivity and 57% specificity and preceded diagnosis according to EORTC-MSG criteria in 41% of cases. In IFD responding to therapy, median days to PCT <500 pg/mL and defervescence were 5 (1-23 vs. 10 (3-22; p = 0.026, respectively. CONCLUSION: While procalcitonin is not useful for diagnosis of infection at onset of neutropenic fever, it may help to distinguish a minority of potentially severe infections among FUOs on day 2 after onset of fever. In persistent fever monitoring procalcitonin contributes to early diagnosis and follow-up of invasive mycoses.

Product consistency leach tests of Savannah River Site radioactive waste glasses

International Nuclear Information System (INIS)

Bibler, N.E.; Bates, J.K.

1990-01-01

The product consistency test (PCT) is a glass leach test developed at the Savannah River Site (SRS) to confirm the durability of radioactive nuclear waste glasses that will be produced in the Defense Waste Processing Facility. The PCT is a seven day, crushed glass leach test in deionized water at 90C. Final leachates are filtered and acidified prior to analysis. To demonstrate the reproducibility of the PCT when performed remotely, SRS and Argonne National Laboratory have performed the PCT on samples of two radioactive glasses. The tests were also performed to compare the releases of the radionuclides with the major nonradioactive glass components and to determine if radiation from the glass was affecting the results of the PCT. The test was performed in triplicate at each laboratory. For the major soluble elements, B, Li, Na, and Si, in the glass, each investigator obtained relative precisions in the range 2-5% in the triplicate tests. This range indicates good precision for the PCT when performed remotely with master slave manipulators in a shielded cell environment. When the results of the two laboratories were compared to each other, the agreement was within 20%. Normalized concentrations for the nonradioactive and radioactive elements in the PCT leachates measured at both facilities indicated that the radionuclides were released from the glass slower than the major soluble elements in the glass. For both laboratories, the normalized releases for both glasses were in the general order Li ∼ B ∼ Na > Si > Cs - 137 > Sb - 125 < Sr - 90. The normalized releases for the major soluble elements and the final pH values in the tests with radioactive glass are consistent with those for nonradioactive glasses with similar compositions. This indicates that there was no significant effect of radiation on the results of the PCT

The Effects of Antimony Addition on the Microstructural, Mechanical, and Thermal Properties of Sn-3.0Ag-0.5Cu Solder Alloy

Science.gov (United States)

Sungkhaphaitoon, Phairote; Plookphol, Thawatchai

2018-02-01

In this study, we investigated the effects produced by the addition of antimony (Sb) to Sn-3.0Ag-0.5Cu-based solder alloys. Our focus was the alloys' microstructural, mechanical, and thermal properties. We evaluated the effects by means of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), differential scanning calorimetry (DSC), and a universal testing machine (UTM). The results showed that a part of the Sb was dissolved in the Sn matrix phase, and the remaining one participated in the formation of intermetallic compounds (IMCs) of Ag3(Sn,Sb) and Cu6(Sn,Sb)5. In the alloy containing the highest wt pct Sb, the added component resulted in the formation of SnSb compound and small particle pinning of Ag3(Sn,Sb) along the grain boundary of the IMCs. Our tests of the Sn-3.0Ag-0.5Cu solder alloys' mechanical properties showed that the effects produced by the addition of Sb varied as a function of the wt pct Sb content. The ultimate tensile strength (UTS) increased from 29.21 to a maximum value of 40.44 MPa, but the pct elongation (pct EL) decreased from 48.0 to a minimum 25.43 pct. Principally, the alloys containing Sb had higher UTS and lower pct EL than Sb-free solder alloys due to the strengthening effects of solid solution and second-phase dispersion. Thermal analysis showed that the alloys containing Sb had a slightly higher melting point and that the addition amount ranging from 0.5 to 3.0 wt pct Sb did not significantly change the solidus and liquidus temperatures compared with the Sb-free solder alloys. Thus, the optimal concentration of Sb in the alloys was 3.0 wt pct because the microstructure and the ultimate tensile strength of the SAC305 solder alloys were improved.

SU-E-J-122: The CBCT Dose Calculation Using a Patient Specific CBCT Number to Mass Density Conversion Curve Based On a Novel Image Registration and Organ Mapping Method in Head-And-Neck Radiation Therapy

International Nuclear Information System (INIS)

Zhou, J; Lasio, G; Chen, S; Zhang, B; Langen, K; Prado, K; D’Souza, W; Yi, B; Huang, J

2015-01-01

Purpose: To develop a CBCT HU correction method using a patient specific HU to mass density conversion curve based on a novel image registration and organ mapping method for head-and-neck radiation therapy. Methods: There are three steps to generate a patient specific CBCT HU to mass density conversion curve. First, we developed a novel robust image registration method based on sparseness analysis to register the planning CT (PCT) and the CBCT. Second, a novel organ mapping method was developed to transfer the organs at risk (OAR) contours from the PCT to the CBCT and corresponding mean HU values of each OAR were measured in both the PCT and CBCT volumes. Third, a set of PCT and CBCT HU to mass density conversion curves were created based on the mean HU values of OARs and the corresponding mass density of the OAR in the PCT. Then, we compared our proposed conversion curve with the traditional Catphan phantom based CBCT HU to mass density calibration curve. Both curves were input into the treatment planning system (TPS) for dose calculation. Last, the PTV and OAR doses, DVH and dose distributions of CBCT plans are compared to the original treatment plan. Results: One head-and-neck cases which contained a pair of PCT and CBCT was used. The dose differences between the PCT and CBCT plans using the proposed method are −1.33% for the mean PTV, 0.06% for PTV D95%, and −0.56% for the left neck. The dose differences between plans of PCT and CBCT corrected using the CATPhan based method are −4.39% for mean PTV, 4.07% for PTV D95%, and −2.01% for the left neck. Conclusion: The proposed CBCT HU correction method achieves better agreement with the original treatment plan compared to the traditional CATPhan based calibration method

SU-C-207A-03: Development of Proton CT Imaging System Using Thick Scintillator and CCD Camera

Energy Technology Data Exchange (ETDEWEB)

Tanaka, S; Uesaka, M [The University of Tokyo, Tokyo (Japan); Nishio, T; Tsuneda, M [Hiroshima University, Hiroshima (Japan); Matsushita, K [Rikkyo University, Tokyo (Japan); Kabuki, S [Tokai University, Isehara (Japan)

2016-06-15

Purpose: In the treatment planning of proton therapy, Water Equivalent Length (WEL), which is the parameter for the calculation of dose and the range of proton, is derived by X-ray CT (xCT) image and xCT-WEL conversion. However, about a few percent error in the accuracy of proton range calculation through this conversion has been reported. The purpose of this study is to construct a proton CT (pCT) imaging system for an evaluation of the error. Methods: The pCT imaging system was constructed with a thick scintillator and a cooled CCD camera, which acquires the two-dimensional image of integrated value of the scintillation light toward the beam direction. The pCT image is reconstructed by FBP method using a correction between the light intensity and residual range of proton beam. An experiment for the demonstration of this system was performed with 70-MeV proton beam provided by NIRS cyclotron. The pCT image of several objects reconstructed from the experimental data was evaluated quantitatively. Results: Three-dimensional pCT images of several objects were reconstructed experimentally. A finestructure of approximately 1 mm was clearly observed. The position resolution of pCT image was almost the same as that of xCT image. And the error of proton CT pixel value was up to 4%. The deterioration of image quality was caused mainly by the effect of multiple Coulomb scattering. Conclusion: We designed and constructed the pCT imaging system using a thick scintillator and a CCD camera. And the system was evaluated with the experiment by use of 70-MeV proton beam. Three-dimensional pCT images of several objects were acquired by the system. This work was supported by JST SENTAN Grant Number 13A1101 and JSPS KAKENHI Grant Number 15H04912.

SU-E-J-122: The CBCT Dose Calculation Using a Patient Specific CBCT Number to Mass Density Conversion Curve Based On a Novel Image Registration and Organ Mapping Method in Head-And-Neck Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Zhou, J [University of Maryland School of Medicine, Bel Air, MD (United States); Lasio, G; Chen, S; Zhang, B; Langen, K; Prado, K; D’Souza, W [University of Maryland School of Medicine, Baltimore, MD (United States); Yi, B [Univ. of Maryland School Of Medicine, Baltimore, MD (United States); Huang, J [University of Texas at Arlington, Arlington, TX (United States)

2015-06-15

Purpose: To develop a CBCT HU correction method using a patient specific HU to mass density conversion curve based on a novel image registration and organ mapping method for head-and-neck radiation therapy. Methods: There are three steps to generate a patient specific CBCT HU to mass density conversion curve. First, we developed a novel robust image registration method based on sparseness analysis to register the planning CT (PCT) and the CBCT. Second, a novel organ mapping method was developed to transfer the organs at risk (OAR) contours from the PCT to the CBCT and corresponding mean HU values of each OAR were measured in both the PCT and CBCT volumes. Third, a set of PCT and CBCT HU to mass density conversion curves were created based on the mean HU values of OARs and the corresponding mass density of the OAR in the PCT. Then, we compared our proposed conversion curve with the traditional Catphan phantom based CBCT HU to mass density calibration curve. Both curves were input into the treatment planning system (TPS) for dose calculation. Last, the PTV and OAR doses, DVH and dose distributions of CBCT plans are compared to the original treatment plan. Results: One head-and-neck cases which contained a pair of PCT and CBCT was used. The dose differences between the PCT and CBCT plans using the proposed method are −1.33% for the mean PTV, 0.06% for PTV D95%, and −0.56% for the left neck. The dose differences between plans of PCT and CBCT corrected using the CATPhan based method are −4.39% for mean PTV, 4.07% for PTV D95%, and −2.01% for the left neck. Conclusion: The proposed CBCT HU correction method achieves better agreement with the original treatment plan compared to the traditional CATPhan based calibration method.

Clinical pulmonary infection score and a spot serum procalcitonin level to guide discontinuation of antibiotics in ventilator-associated pneumonia: a study in a single institution with high prevalence of nonfermentative gram-negative bacilli infection.

Science.gov (United States)

Wongsurakiat, Phunsup; Tulatamakit, Sirapat

2018-01-01

Background We wanted to determine the impact of combined Clinical Pulmonary Infection Score (CPIS) and a spot serum procalcitonin (PCT)-guided protocol to shorten the duration of antibiotic treatment in patients with ventilator-associated pneumonia (VAP), mainly caused by nonfermentative gram-negative bacilli (NF-GNB). Methods Patients with VAP who received appropriate antibiotics for 7 days, temperature ⩽ 37.8°C, without shock, and CPIS ⩽ 6 were allocated to the PCT group or conventional group according to the treating physicians' decisions. In the PCT group, antibiotics were stopped if the PCT level on day 8 level appeared effective and safe to guide discontinuation of antibiotic treatment in patients with VAP caused by NF-GNB. TCTR20160726002.

Microstructure and Ductility-Dip Cracking Susceptibility of Circumferential Multipass Dissimilar Weld Between 20MND5 and Z2CND18-12NS with Ni-Base Filler Metal 52

Science.gov (United States)

Qin, Renyao; Duan, Zhaoling; He, Guo

2013-10-01

The large circumferential multipass dissimilar weld between 20MND5 steel and Z2CND18-12NS stainless steel welded with FM52 filler material was investigated in terms of the diluted composition, the grain boundary precipitation, and the ductility-dip cracking (DDC) susceptibility of the weld. The diluted composition of the weld is composed of 37 to 47 pct Ni, 21 to 24 pct Cr, and 28 to 40 pct Fe, which are inhomogeneous along the depth and over the width of the deep weld. The carbon content has a distribution in the region of the surface weld from a high level (~0.20 pct) in the zone near 20MND5 steel to a normal level (~0.03 pct) in the zone near Z2CND18-12NS stainless steel. The carbon distribution is corresponding to the grain boundary carbides. The minimum threshold strains for DDC occur in the temperature range of 1223 K to 1323 K (950 °C to 1050 °C), which are 0.5, 0.35, and 0.4 pct for the root weld, middle region, and the surface weld, respectively. The dissimilar weld has the largest susceptibility to the DDC compared to the filler metal 52 and the Inconel 690.

Influence of dihydroxybenzenes on paracetamol and ciprofloxacin degradation and iron(III) reduction in Fenton processes.

Science.gov (United States)

Costa E Silva, Beatriz; de Lima Perini, João Angelo; Nogueira, Raquel F Pupo

2017-03-01

The degradation of paracetamol (PCT) and ciprofloxacin (CIP) was compared in relation to the generation of dihydroxylated products, Fe(III) reduction and reaction rate in the presence of dihydroxybenzene (DHB) compounds, or under irradiation with free iron (Fe 3+ ) or citrate complex (Fecit) in Fenton or photo-Fenton process. The formation of hydroquinone (HQ) was observed only during PCT degradation in the dark, which increased drastically the rate of PCT degradation, since HQ formed was able to reduce Fe 3+ and contributed to PCT degradation efficiency. When HQ was initially added, PCT and CIP degradation rate in the dark was much higher in comparison to the absence of HQ, due to the higher and faster formation of Fe 2+ at the beginning of reaction. In the absence of HQ, no CIP degradation was observed; however, when HQ was added after 30 min, the degradation rate increased drastically. Ten PCT hydroxylated intermediates were identified in the absence of HQ, which could contribute for Fe(III) reduction and consequently to the degradation in a similar way as HQ. During CIP degradation, only one product of hydroxyl radical attack on benzene ring and substitution of the fluorine atom was identified when HQ was added to the reaction medium.

Usefulness of a semi-quantitative procalcitonin test and the A-DROP Japanese prognostic scale for predicting mortality among adults hospitalized with community-acquired pneumonia.

Science.gov (United States)

Kasamatsu, Yu; Yamaguchi, Toshimasa; Kawaguchi, Takashi; Tanaka, Nagaaki; Oka, Hiroko; Nakamura, Tomoyuki; Yamagami, Keiko; Yoshioka, Katsunobu; Imanishi, Masahito

2012-02-01

The solid-phase immunoassay, semi-quantitative procalcitonin (PCT) test (B R A H M S PCT-Q) can be used to rapidly categorize PCT levels into four grades. However, the usefulness of this kit for determining the prognosis of adult patients with community-acquired pneumonia (CAP) is unclear. A prospective study was conducted in two Japanese hospitals to evaluate the usefulness of this PCT test in determining the prognosis of adult patients with CAP. The accuracy of the age, dehydration, respiratory failure, orientation disturbance, pressure (A-DROP) scale proposed by the Japanese Respiratory Society for prediction of mortality due to CAP was also investigated. Hospitalized CAP patients (n = 226) were enrolled in the study. Comprehensive examinations were performed to determine PCT and CRP concentrations, disease severity based on the A-DROP, pneumonia severity index (PSI) and confusion, urea, respiratory rate, blood pressure, age ≥65 (CURB-65) scales and the causative pathogens. The usefulness of the biomarkers and prognostic scales for predicting each outcome were then examined. Twenty of the 170 eligible patients died. PCT levels were strongly positively correlated with PSI (ρ = 0.56, P scale were found to be useful for predicting mortality in adult patients with CAP. © 2011 The Authors. Respirology © 2011 Asian Pacific Society of Respirology.

The thermodynamic activity of ZnO in silicate melts

Science.gov (United States)

Reyes, R. A.; Gaskell, D. R.

1983-12-01

The activity of ZnO in ZnO-SiO2 and CaO-ZnO-SiO2 melts has been measured at 1560 °C using a transpiration technique with CO-CO2 mixtures as the carrier gas. The activities of ZnO in dilute solution in 42 wt pct SiO2-38 wt pct CaO-20 wt pct A12O3 in the range 1400° to 1550 °C and in 62 wt pct SiO2-23.3 wt pct CaO-14.7 wt pct A12O3 at 1550 °C have also been measured. The measured free energies of formation of ZnO-SiO2 melts are significantly more negative than published estimated values and this, together with the behavior observed in the system CaO-Al2O3-SiO2, indicate that ZnO is a relatively basic oxide. The results are discussed in terms of the polymerization model of binary silicate melts and ideal silicate mixing in ternary silicate melts. The behavior of ZnO in dilute solution in CaO-Al2O3-SiO2 melts is discussed in terms of the possibility of the fluxing of ZnO by iron blast furnace slags.

Comparison of Procalcitonin Guidance-Administered Antibiotics with Standard Guidelines on Antibiotic Therapy in Children with Lower Respiratory Tract Infections: A Retrospective Study in China.

Science.gov (United States)

Wu, Guo; Wu, Gao; Wu, Shuxie; Wu, Hanbin

2017-01-01

To establish the efficacy of an algorithm based on the biomarker procalcitonin (PCT) to reduce antibiotic exposure in pediatric patients with lower respiratory tract infection (LRTI). The clinical data of 357 patients (standard group (n = 174) using SAS 9.1.3 software. The overall adverse effect rates were similar in both the PCT and standard groups: 42 (22.95%) and 51 (29.31%), respectively. The length of hospital stay was not significantly different between the PCT (9.96 ± 5.81 days) and standard groups (10.58 ± 4.24 days) (difference: -0.62%; 95% CI: -1.68 to 0.43). Antibiotic prescribing rates were significantly different in the PCT group compared to the standard group: 54.64% versus 83.91% (difference: -29.26%; 95% CI: -38.31, -20.22; p = 0.23). Mean duration of antibiotic exposure in the PCT group (3.98 ± 2.17 days) was lower than the standard groups (6.66 ± 5.59 days) (difference: -2.68%; 95% CI: -3.21 to -2.16). This study showed that PCT guidance of antibiotic treatment in children and adolescents with LRTI reduced the duration of antibiotic exposure and antibiotic prescribing rates, but did not affect the adverse effect rate and length of hospital stay. © 2017 S. Karger AG, Basel.

Application of serum procalcitonin in differential diagnosis between child acute bacterial meningitis and viral meningitis%血清PCT检测在小儿急性细菌性脑膜炎及病毒性脑炎鉴别诊断中的应用

Institute of Scientific and Technical Information of China (English)

黄小明; 张春荣

2016-01-01

Objective To observe and analyze the application ,sensitivity and specificity of serum procalcitonin (PCT ) in the dif‐ferential diagnosis of child acute bacterial meningitis and viral meningitis .Methods One hundred and sixty‐four children patients with bacterial meningitis ,98 children patients with viral meningitis and 60 healthy children were selected as the research subjects . The serum PCT ,white blood cell (WBC) count ,erythrocyte sedimentation rate (ESR) and C‐reactive protein (CRP) levels were detected by using electrochemical luminescence immunity assay .The laboratory detection results ,PCT detection results distribu‐tion ,sensitivity and specificity in the two groups were analyzed .Results The PCT ,CRP and WBC detection results in children pa‐tients with bacterial meningitis were higher than those in children patients with viral meningitis .The positive rates of PCT and WBC in the bacterial meningitis group were higher than those in the viral meningitis group ,while the constituent ratio of PCT detection distribution had statistically significant difference between the two groups(χ2 = 16 .151 ,P< 0 .01) .The sensitivity of PCT detection in differentially diagnosing viral meningitis was 97 .6% (160/164) ,the specificity was 95 .0% (57/60) and the misdiagnosis rate was 3 .1% (7/224) .The sensitivity of PCT detection in differentially diagnosing bacterial meningitis was 98 .0% (96/98) ,the specificity was 96 .7% (58/60) and the misdiagnosis rate was 2 .5% (4/158) .Conclusion The serum PCT as a differential diagnosis index of child acute bacterial meningitis and viral meningitis has good accuracy ,its combination with CRP ,WBC ,ESR in combined differenti‐al diagnosis can rapidly give accurate pathogenic diagnosis in the early stage ,thus increases the pertinence of clinical treatment ,re‐duces the occurrence of antibiotics abuse and is ,worthy of clinical popularization and application .%目的：观察分析血清降钙素原（PCT �

The anterior cerebral artery is an appropriate arterial input function for perfusion-CT processing in patients with acute stroke

International Nuclear Information System (INIS)

Wintermark, Max; Lau, Benison C.; Chien, Jeffrey; Arora, Sandeep

2008-01-01

Dynamic perfusion-CT (PCT) with deconvolution requires an arterial input function (AIF) for postprocessing. In clinical settings, the anterior cerebral artery (ACA) is often chosen for simplicity. The goals of this study were to determine how the AIF selection influences PCT results in acute stroke patients and whether the ACA is an appropriate default AIF. We retrospectively identified consecutive patients suspected of hemispheric stroke of less than 48 h duration who were evaluated on admission by PCT. PCT datasets were postprocessed using multiple AIF, and cerebral blood volume (CBV) and flow (CBF), and mean transit time (MTT) values were measured in the corresponding territories. Results from corresponding territories in the same patients were compared using paired t-tests. The volumes of infarct core and tissue at risk obtained with different AIFs were compared to the final infarct volume. Of 113 patients who met the inclusion criteria, 55 with stroke were considered for analysis. The MTT values obtained with an ''ischemic'' AIF tended to be shorter (P=0.055) and the CBF values higher (P=0.108) than those obtained using a ''nonischemic'' AIF. CBV values were not influenced by the selection of the AIF. No statistically significant difference was observed between the size of the PCT infarct core (P=0.121) and tissue at risk (P=0.178), regardless of AIF selection. In acute stroke patients, the selection of the AIF has no statistically significant impact of the PCT results; standardization of the PCT postprocessing using the ACA as the default AIF is adequate. (orig.)

Procalcitonin as a biomarker for severe Plasmodium falciparum disease: a critical appraisal of a semi-quantitative point-of-care test in a cohort of travellers with imported malaria

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Petit Pieter

2009-09-01

Full Text Available Abstract Background Imported malaria occurs as a relatively rare event in developed countries. As a consequence, most clinicians have little experience in making clinical assessments of disease severity and decisions regarding the need for parenteral therapy or high-level monitoring. In this study, the diagnostic accuracy of procalcitonin (PCT for severe Plasmodium falciparum disease was assessed in a cohort of 100 consecutive travellers with various species of imported malaria. Methods and results In all patients, PCT was measured on admission with a semi-quantitative 'point-of-care' test. Patients with severe P. falciparum malaria had significantly higher median PCT levels on admission as compared with patients with uncomplicated P. falciparum disease. In addition, PCT levels in patients with non-falciparum malaria were also higher compared with patients with non-severe falciparum malaria but lower compared with severe P. falciparum malaria. At a cut-off point of 10 ng/mL, PCT had a sensitivity of 0,67 and a specificity of 0,94 for severe falciparum disease. However, at lower cut-off points the specificity and positive predictive value were rather poor although the sensitivity and negative predictive value remained high. Discussion Potential drawbacks in the interpretation of elevated PCT levels on admission may be caused by infections with non-falciparum species and by concomitant bacterial infections. Conclusion Semi-quantitative determination of PCT on admission is of limited use in the initial clinical assessment of disease severity in travellers with imported malaria, especially in settings with limited experience with the treatment of malaria.

Diagnostic performance of procalcitonin for hospitalised children with acute pyelonephritis presenting to the paediatric emergency department.

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Chen, Shan-Ming; Chang, Hung-Ming; Hung, Tung-Wei; Chao, Yu-Hua; Tsai, Jeng-Dau; Lue, Ko-Huang; Sheu, Ji-Nan

2013-05-01

Urinary tract infection (UTI) is a common bacterial infection in children that can result in permanent renal damage. This study prospectively assessed the diagnostic performance of procalcitonin (PCT) for predicting acute pyelonephritis (APN) among children with febrile UTI presenting to the paediatric emergency department (ED). Children aged ≤10 years with febrile UTI admitted to hospital from the paediatric ED were prospectively studied. Blood PCT, C reactive protein (CRP) and white blood cell (WBC) count were measured in the ED. Sensitivity, specificity, predictive values, multilevel likelihood ratios, receiver operating characteristic (ROC) curve analysis and multivariate logistic regression were used to assess quantitative variables for diagnosing APN. The 136 enrolled patients (56 boys and 80 girls; age range 1 month to 10 years) were divided into APN (n=87) and lower UTI (n=49) groups according to (99m)Tc-dimercaptosuccinic acid scan results. The cut-off value for maximum diagnostic performance of PCT was 1.3 ng/ml (sensitivity 86.2%, specificity 89.8%). By multivariate regression analysis, only PCT and CRP were retained as significant predictors of APN. Comparing ROC curves, PCT had a significantly greater area under the curve than CRP, WBC count and fever for differentiating between APN and lower UTI. PCT has better sensitivity and specificity than CRP and WBC count for distinguishing between APN and lower UTI. PCT is a valuable marker for predicting APN in children with febrile UTI. It may be considered in the initial investigation and therapeutic strategies for children presenting to the ED.

[Acceptance of lot sampling: its applicability to the evaluation of the primary care services portfolio].

Science.gov (United States)

López-Picazo Ferrer, J

2001-05-15

To determine the applicability of the acceptance of lot quality assurance sampling (LQAS) in the primary care service portfolio, comparing its results with those given by classic evaluation. Compliance with the minimum technical norms (MTN) of the service of diabetic care was evaluated through the classic methodology (confidence 95%, accuracy 5%, representativeness of area, sample of 376 histories) and by LQAS (confidence 95%, power 80%, representativeness of primary care team (PCT), defining a lot by MTN and PCT, sample of 13 histories/PCT). Effort, information obtained and its operative nature were assessed. 44 PCTs from Murcia Primary Care Region. Classic methodology: compliance with MTN ranged between 91.1% (diagnosis, 95% CI, 84.2-94.0) and 30% (repercussion in viscera, 95% CI, 25.4-34.6). Objectives in three MTN were reached (diagnosis, history and EKG). LQAS: no MTN was accepted in all the PCTs, being the most accepted (42 PCT, 95.6%) and the least accepted (24 PCT, 55.6%). In 9 PCT all were accepted (20.4%), and in 2 none were accepted (4.5%). Data were analysed through Pareto charts. Classic methodology offered accurate results, but did not identify which centres were those that did not comply (general focus). LQAS was preferable for evaluating MTN and probably coverage because: 1) it uses small samples, which foment internal quality-improvement initiatives; 2) it is easy and rapid to execute; 3) it identifies the PCT and criteria where there is an opportunity for improvement (specific focus), and 4) it can be used operatively for monitoring.

suPAR remains uninfluenced by surgery in septic patients with bloodstream infection

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Rabensteiner, Jasmin

2016-07-01

Full Text Available Surgical trauma induces activation of the immune system and may cause an increase of inflammatory biomarkers tested postoperatively in septic patients treated for bloodstream infection. The aim of this study was to determine the impact of surgical interventions on the novel sepsis biomarker soluble urokinase plasminogen activator receptor (suPAR and to compare results with those of routine laboratory parameters CRP, PCT, and IL-6 in patients with culture-proven bloodstream infection. Forty-six adult patients with positive blood culture undergoing minor or major surgical intervention were investigated, 12 blood culture positive patients served as control group. Blood was collected 24 hours before and after surgical intervention for determination of the sepsis biomarkers suPAR, CRP, PCT, and IL-6. Within the surgical study cohort, a non-significant increase of suPAR, CRP, and PCT was observed postoperatively ( 0.642; 0.773; 0.087. In contrast, a slight decrease of IL-6 ( 0.599 was observed. A significant correlation was calculated for the pre- and postoperative difference of CRP ( 0.028 and PCT and type of surgical intervention received: after minor surgical intervention only PCT decreased significantly (<0.001, while after major surgical interventions no significant differences were observed for all biomarkers evaluated. In the control group, a significant decrease of CRP ( 0.005 and PCT ( 0.005 was observed. In patients treated adequately for bloodstream infections, postoperative suPAR levels remained uninfluenced of the surgical trauma and might therefore be a reliable parameter for postoperative infectious monitoring. After minor surgical intervention, PCT seems to be the most reliable parameter.

N-13 ammonia positron tomography at rest and during exercise for evaluation of coronary artery disease

International Nuclear Information System (INIS)

Tamaki, N.; Yonekura, Y.; Senda, M.

1985-01-01

To assess the value of positron computed tomography (PCT) for evaluation of coronary artery disease (CAD), N-13 ammonia myocardial PCT was performed at rest and during exercise in 23 cases. PCT imaging was taken with a wholebody multislice PCT device 3 minutes after intravenous injection of 20-20 mCi of N-13 ammonia. The tracer distribution was homogenous in the left ventricular myocardium at rest and during exercise in all 4 normal cases. Among 19 cases with CAD, regional hypoperfusion was observed in 24 cases (74%) at rest and 18 cases (95%) during exercise. Furthermore, 12 cases had regional perfusion abnormalities in stress images not present at rest. Segmental analysis of myocardial perfusion identified 30 of the 34 stenosed vessels (88%) with only one false positive finding (specificity: 97%). In 11 patients who underwent both thallium-201 and N-13 ammonia imaging, PCT detected stenosed vessels more (87%) than the thallium-201 imaging (63%: p<0.05), especially in those with multivessel disease (87% vs 63%: p 0.05). For quantitative analysis of myocardial perfusion by PCT, % change in tracer concentration from resting to stress state was calculated. It was mildly increased (14.4+- 5.8%: p<0.001) in normal segments, whereas in CAD, it was significantly decreased (-18.0+- 18.3%: p<0.02) in segments with stenosed vessels. The authors conclude that N-13 ammonia PCT during exercise is a sensitive and effective method for detecting CAD and identifying stenosed vessels, and it permits quantitative assessment of coronary reserve function

Immature platelet fraction in bacterial sepsis severity assessment

Science.gov (United States)

Djuang, M. H.; Ginting, F.; Hariman, H.

2018-03-01

Sepsis is an infection-induced syndrome, mostly caused by bacteria, of organ dysfunctions that caused by host response dysregulations. One of the simplest sepsis-indicator is platelet and its indexes. A new platelet parameter called immature platelet count (IPF) became theinterest in this study. The study aims to see whether IPF could assess sepsis severity by procalcitonin (PCT).Sixty-four of seventy-one patients with increased PCT were included in this cross-sectional study and separated into three groups based on their PCT levels. IPF showed no significance among the three groups (p-value>0.05) while platelet count was significant (p-valuesepsis severity based on PCT showed larger platelet count, as the result of platelet destructions caused by pro-inflammatory cytokines and endotoxins.

A Prospective Study to Compare the Diagnostic Value of Serum Procalcitonin and Crp in Early Onset Sepsis

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Suresh Kumar Verma

2017-10-01

Full Text Available Introduction: Neonatal sepsis is the most common cause of death in newborns in developing countries. Prompt diagnosis is the critical determinant in its outcome. As manifestations are often vague, clinically it is difficult to differentiate sepsis from non-infective conditions. Timely diagnosis is important as delay in initiation of antimicrobials can prove fatal. On the other hand empirical use of antibiotics not only increases the risk of antibiotic resistance but also delays the diagnosis of true condition. Procalcitonin (PCT has been well evaluated in late onset sepsis but data pertaining to Early Onset Sepsis (EOS are still lacking. We compared the diagnostic value of PCT and CRP (C-Reactive Protein in EOS. Aim: To compare the diagnostic value of serum PCT and CRP in early onset sepsis. Materials and Methods: It was a prospective observational study conducted in Neonatal Intensive Care Unit of the Department of Paediatrics, Dr.S.N. Medical College, Jodhpur, India. All neonates delivered in hospitals attached to this medical college or referred here within 7 days of life and having ≥2 perinatal risk factors for sepsis or displaying clinical sepsis were included in the study. All enrolled neonates were subjected to sepsis screen, PCT levels and blood culture at birth or admission which ever was the earliest. PCT levels ≥ 0.5 ng/ml and CRP levels above 8mg/l were considered positive for EOS. Results: Sensitivity and negative predictive value of PCT were higher than CRP (90.12% vs. 50.62% and 93.33% vs. 79.06% respectively. Also it had a higher positive predictive value of 40.56% than CRP where it was 37.61%. CRP was more specific (68.95% vs. 51.4% with overall higher diagnostic accuracy (0.64 vs. 0.61 in comparison to PCT. Conclusion: PCT is more sensitive and has a higher negative predictive value than CRP in early onset sepsis. Higher positive predictive value and specificity of CRP suggest that, PCT should not be used alone rather

Contouring variability of human- and deformable-generated contours in radiotherapy for prostate cancer

International Nuclear Information System (INIS)

Gardner, Stephen J; Wen, Ning; Kim, Jinkoo; Liu, Chang; Pradhan, Deepak; Aref, Ibrahim; Cattaneo, Richard II; Vance, Sean; Movsas, Benjamin; Chetty, Indrin J; Elshaikh, Mohamed A

2015-01-01

This study was designed to evaluate contouring variability of human-and deformable-generated contours on planning CT (PCT) and CBCT for ten patients with low-or intermediate-risk prostate cancer. For each patient in this study, five radiation oncologists contoured the prostate, bladder, and rectum, on one PCT dataset and five CBCT datasets. Consensus contours were generated using the STAPLE method in the CERR software package. Observer contours were compared to consensus contour, and contour metrics (Dice coefficient, Hausdorff distance, Contour Distance, Center-of-Mass [COM] Deviation) were calculated. In addition, the first day CBCT was registered to subsequent CBCT fractions (CBCTn: CBCT2–CBCT5) via B-spline Deformable Image Registration (DIR). Contours were transferred from CBCT1 to CBCTn via the deformation field, and contour metrics were calculated through comparison with consensus contours generated from human contour set. The average contour metrics for prostate contours on PCT and CBCT were as follows: Dice coefficient—0.892 (PCT), 0.872 (CBCT-Human), 0.824 (CBCT-Deformed); Hausdorff distance—4.75 mm (PCT), 5.22 mm (CBCT-Human), 5.94 mm (CBCT-Deformed); Contour Distance (overall contour)—1.41 mm (PCT), 1.66 mm (CBCT-Human), 2.30 mm (CBCT-Deformed); COM Deviation—2.01 mm (PCT), 2.78 mm (CBCT-Human), 3.45 mm (CBCT-Deformed). For human contours on PCT and CBCT, the difference in average Dice coefficient between PCT and CBCT (approx. 2%) and Hausdorff distance (approx. 0.5 mm) was small compared to the variation between observers for each patient (standard deviation in Dice coefficient of 5% and Hausdorff distance of 2.0 mm). However, additional contouring variation was found for the deformable-generated contours (approximately 5.0% decrease in Dice coefficient and 0.7 mm increase in Hausdorff distance relative to human-generated contours on CBCT). Though deformable contours provide a reasonable starting point for contouring

Diagnostic value of soluble CD163 serum levels in patients suspected of meningitis: comparison with CRP and procalcitonin

DEFF Research Database (Denmark)

Knudsen, Troels Bygum; Larsen, Klaus; Kristiansen, Thomas Birk

2007-01-01

The aim of the study was to evaluate and compare the diagnostic value of sCD163 serum levels with CRP and PCT in meningitis and bacterial infection. An observational cohort study was conducted between February 2001 and February 2005. The study population comprised 55 patients suspected of meningi......The aim of the study was to evaluate and compare the diagnostic value of sCD163 serum levels with CRP and PCT in meningitis and bacterial infection. An observational cohort study was conducted between February 2001 and February 2005. The study population comprised 55 patients suspected...... marker for distinguishing bacterial infection from non-bacterial disease (specificity 0.91; sensitivity 0.47). However, the overall diagnostic accuracy of CRP (AUC =0.91) and PCT (AUC =0.87) were superior (p... infection, the AUC of sCD163 (0.83) did not differ significantly from those of CRP or PCT. All markers had AUCs CRP and PCT had high diagnostic value and were superior as markers of bacterial infection compared to s...

The influence of cobalt, tantalum, and tungsten on the elevated temperature mechanical properties of single crystal nickel-base superalloys

Science.gov (United States)

Nathal, M. V.; Ebert, L. J.

1985-01-01

The influence of composition on the tensile and creep strength of 001-line oriented nickel-base superalloy single crystals at temperatures near 1000 C was investigated. Cobalt, tantalum, and tungsten concentrations were varied according to a matrix of compositions based on the single crystal version of MAR-M247. For alloys with the baseline refractory metal level of 3 wt pct Ta and 10 wt pct W, decreases in Co level from 10 to 0 wt pct resulted in increased tensile and creep strength. Substitution of 2 wt pct W for 3 wt pct Ta resulted in decreased creep life at high stresses, but improved life at low stresses. Substitution of Ni for Ta caused large reductions in tensile strength and creep resistance, and corresponding increases in ductility. For these alloys with low Ta-plus-W totals, strength was independent of Co level. The effects of composition on properties were related to the microstructural features of the alloys. In general, high creep strength was associated with high levels of gamma-prime volume fraction, gamma-gamma-prime lattice mismatch, and solid solution hardening.

Psychic centrality: reflections on two psychohistoriographic cultural therapy workshops in Montreal.

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Hickling, Frederick W; Guzder, Jaswant; Robertson-Hickling, Hilary; Snow, Stephen; Kirmayer, Laurence J

2010-02-01

The use of psychohistoriographic cultural therapy (PCT) developed in Jamaica is described in the context of two workshops in Montreal. PCT is a form of group intervention that seeks to elicit and clarify the "psychic centrality" of a group. Psychic centrality refers to a sense of psychological containment or organization of diverse individual points of view through creating a historical map of collective experience. In PCT, this collective map is constructed and techniques borrowed from creative arts therapies are used to develop a performance. This performance provides additional containment and fosters a group process that can contain collective conflicts. The performance can also be used to engage an audience, working to contain conflict while representing diverse perspectives within the group. Factors that may contribute to the effectiveness of PCT and those that may derail the process are identified through the systematic comparison of the two workshops. PCT was demonstrated to cross successfully from a Third to a First World culture, and established potential as a method to facilitate group conflict resolution and for the promotion of pluralistic civil societies.

Regional myocardial perfusion assessed by N-13 labeled ammonia and positron emission computerized axial tomography

International Nuclear Information System (INIS)

Schelbert, H.R.; Phelps, M.E.; Hoffman, E.J.; Huang, S.C.; Selin, C.E.; Kuhl, D.E.

1978-01-01

The usefulness of 13 NH 3 as an indicator of regional myocardial perfusion suitable for positron emission computerized axial tomography (PCT) has been suggested. However, the relationship between myocardial blood flow and uptake of 13 NH 3 has not been examined quantitatively. It was therefore the purpose of the current investigation to quantitate the relationship of myocardial 13 NH 3 tissue concentration to myocardial blood flow and to examine its suitability for PCT imaging. Twelve open chest dogs were studied. In 8 of the dogs 25 imaging procedures with 13 NH 3 and PCT were performed. In the remaining four dogs the relationship between flow and myocardial 13 NH 3 tissue concentration was assessed by in vitro techniques. The PCT technique provided high quality cross-sectional images of the distribution of 13 NH 3 in left ventricular myocardium. No significant redistribution of 13 NH 3 in myocardium occurred with time. Alterations in regional myocardial blood flow resulted in changes of the regional distribution of 13 NH 3 that were readily appreciated on the PCT images

Early changes of procalcitonin may advise about prognosis and appropriateness of antimicrobial therapy in sepsis.

Science.gov (United States)

Georgopoulou, Antonia-Panagiota; Savva, Athina; Giamarellos-Bourboulis, Evangelos J; Georgitsi, Marianna; Raftogiannis, Maria; Antonakos, Nicolaos; Apostolidou, Efterpi; Carrer, Dionyssia-Pinelopi; Dimopoulos, George; Economou, Aggelos; Efthymiou, George; Galanakis, Nearchos; Galani, Labrini; Gargalianos, Panagiotis; Karaiskos, Ilias; Katsenos, Chrisostomos; Kavatha, Dimitra; Koratzanis, Evangelos; Labropoulos, Panagiotis; Lada, Malvina; Nakos, George; Paggalou, Evgenia; Panoutsopoulos, George; Paraschos, Michael; Pavleas, Ioannis; Pontikis, Konstantinos; Poulakou, Garyfallia; Prekates, Athanassios; Sybardi, Styliani; Theodorakopoulou, Maria; Trakatelli, Christina; Tsiaoussis, Panagiotis; Gogos, Charalambos; Giamarellou, Helen; Armaganidis, Apostolos; Meisner, Michael

2011-06-01

The objective of this study is to define if early changes of procalcitonin (PCT) may inform about prognosis and appropriateness of administered therapy in sepsis. A prospective multicenter observational study was conducted in 289 patients. Blood samples were drawn on day 1, that is, within less than 24 hours from advent of signs of sepsis, and on days 3, 7, and 10. Procalcitonin was estimated in serum by the ultrasensitive Kryptor assay (BRAHMS GmbH, Hennigsdorf, Germany). Patients were divided into the following 2 groups according to the type of change of PCT: group 1, where PCT on day 3 was decreased by more than 30% or was below 0.25 ng/mL, and group 2, where PCT on day 3 was either increased above 0.25 ng/mL or decreased less than 30%. Death occurred in 12.3% of patients of group 1 and in 29.9% of those of group 2 (P < .0001). Odds ratio for death of patients of group 1 was 0.328. Odds ratio for the administration of inappropriate antimicrobials of patients of group 2 was 2.519 (P = .003). Changes of serum PCT within the first 48 hours reflect the benefit or not of the administered antimicrobial therapy. Serial PCT measurements should be used in clinical practice to guide administration of appropriate antimicrobials. Copyright © 2011 Elsevier Inc. All rights reserved.

Microbial Beneficiation of Salem Iron Ore Using Penicillium purpurogenum

Science.gov (United States)

Mishra, M.; Pradhan, M.; Sukla, L. B.; Mishra, B. K.

2011-02-01

High alumina and silica content in the iron ore affects coke rate, reducibility, and productivity in a blast furnace. Iron ore is being beneficiated all around the world to meet the quality requirement of iron and steel industries. Choosing a beneficiation treatment depends on the nature of the gangue present and its association with the ore structure. The advanced physicochemical methods used for the beneficiation of iron ore are generally unfriendly to the environment. Biobeneficiation is considered to be ecofriendly, promising, and revolutionary solutions to these problems. A characterization study of Salem iron ore indicates that the major iron-bearing minerals are hematite, magnetite, and goethite. Samples on average contains (pct) Fe2O3-84.40, Fe (total)-59.02, Al2O3-7.18, and SiO2-7.53. Penicillium purpurogenum (MTCC 7356) was used for the experiment . It removed 35.22 pct alumina and 39.41 pct silica in 30 days in a shake flask at 10 pct pulp density, 308 K (35 °C), and 150 rpm. In a bioreactor experiment at 2 kg scale using the same organism, it removed 23.33 pct alumina and 30.54 pct silica in 30 days at 300 rpm agitation and 2 to 3 l/min aeration. Alumina and silica dissolution follow the shrinking core model for both shake flask and bioreactor experiments.

Procalcitonin - Assisted Antibiotic Strategy in Sepsis.

Science.gov (United States)

Trásy, Domonkos; Molnár, Zsolt

2017-05-01

Sepsis is one of the biggest challenges in critical care nowadays. Defining sepsis is a difficult task on its own and its diagnosis and treatment requires well trained, devoted personnel with interdisciplinary collaboration in order to provide the patients the best chance for survival. Immediate resuscitation, early adequate antimicrobial therapy, source control and highly sophisticated organ support on the intensive care units are all inevitable necessities for successful recovery. To help fast and accurate diagnosis biomarkers have been measured for decades. Procalcitonin (PCT) is one of the most studied, but the results are conflicting. Sepsis means a very loose cohort of a large heterogeneous patient population, hence defining certain cut off values for PCT to differentiate between different severities of the disease is almost impossible. Clinicians first have to understand the pathophysiological background of sepsis to be able to interpret correctly the PCT results. Nevertheless, PCT has been shown to have the best sensitivity and specificity to indicate infection, antibiotic appropriateness and stopping therapy. In this article we will focus on some important aspects of pathophysiology and advice on how to implement that in the everyday clinical practice. We believe that this multimodal evaluation of the clinical picture together with PCT results can be a useful tool to make the most out of the PCT results, and do the best for patients on the ICU.

End-of-life palliative chemotherapy: Where do we stand?

International Nuclear Information System (INIS)

Mohammed, A.A.; Al-Zahrani, A.S.; Ghanem, H.M.; El Saify, A.M.; EL-Khatib, H.M.; Mohammed, A.A.; Farooq, M.U.

2015-01-01

Background: This study evaluates the use of palliative chemotherapy (PCT) and possible associated factors at the end of life. Method: The study includes all advanced non hematological cancer patients who died in the King Abdullah Medical City during the period from January 2011 to April 2014. Demographic and disease features were registered. Results: 420 patients were included in the study, median age 62 years (range 17-108); 52% female and 48% male. 87.4% of patients were Saudis and 12.6% non Saudis. 124 (29.5%) patients received PCT at the last month before death (LM-PCT): 21.8%, 22.6% and 55.6% within one, two and four weeks of death, respectively. Place of death (critical care vs. regular ward) and mode of admission (ER vs. OPD vs. Transferred) had a strong association with LM-PCT (p< 0.0001, / = 0.35) and (p< 0.0001, V = 0.43), respectively. There was a gradual increase in the number of patients receiving LM-PCT from January 2011 to April 2014; 15.3%, 28.2%, 37.1% and 19.4%, respectively. Conclusion: In our center; at the end of life, there is a gradual increase in the number of patients receiving chemotherapy which significantly increased cancer patients’ odds without clear predictive factors associated with its use, which calls into question the benefits of PCT in terminally ill cancer patients.

Selective Oxidation and Reactive Wetting during Galvanizing of a CMnAl TRIP-Assisted Steel

Science.gov (United States)

Bellhouse, E. M.; McDermid, J. R.

2011-09-01

A transformation induced plasticity (TRIP)-assisted steel with 0.2 pct C, 1.5 pct Mn, and 1.5 pct Al was successfully galvanized using a thermal cycle previously shown to produce an excellent combination of strength and ductility. The steel surface chemistry and oxide morphology were determined as a function of process atmosphere oxygen partial pressure. For the 220 K (-53 °C) dew point (dp) + 20 pct H2 atmosphere, the oxide morphology was a mixture of films and nodules. For the 243 K (-30 °C) dp + 5 pct H2 atmosphere, nodules of MnO were found primarily at grain boundaries. For the 278 K (+5 °C) dp + 5 pct H2 atmosphere, nodules of metallic Fe were found on the surface as a result of alloy element internal oxidation. The steel surface chemistry and oxide morphology were then related to the reactive wetting behavior during continuous hot dip galvanizing. Good wetting was obtained using the two lower oxygen partial pressure process atmospheres [220 K dp and 243 K dp (-53 °C dp and -30 °C dp)]. An increase in the number of bare spots was observed when using the higher oxygen partial pressure process atmosphere (+5 °C dp) due to the increased thickness of localized oxide films.

Procalcitonin for the early prediction of renal parenchymal involvement in children with UTI: preliminary results.

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Kotoula, Aggeliki; Gardikis, Stefanos; Tsalkidis, Aggelos; Mantadakis, Elpis; Zissimopoulos, Athanassios; Kambouri, Katerina; Deftereos, Savvas; Tripsianis, Gregorios; Manolas, Konstantinos; Chatzimichael, Athanassios; Vaos, George

2009-01-01

In order to establish the most reliable marker for distinguishing urinary tract infections (UTI) with and without renal parenchymal involvement (RPI), we recorded the clinical features and admission leukocyte count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum procalcitonin (PCT) in 57 children (including 43 girls) aged 2-108 months admitted with a first episode of UTI. RPI was evaluated by Tc-99m dimercaptosuccinic acid (DMSA) scintigraphy within 7 days of admission. To establish cut-off points for ESR, CRP, and PCT, we used receiver operating characteristics curves and compared the area under the curve for ESR, CRP, and PCT. Twenty-seven children were diagnosed as having RPI based on positive renal scintigraphy. A body temperature of >38 degrees C, a history of diarrhea, and poor oral intake were more common in patients with RPI. ESR, CRP, and PCT, but not leukocyte count, were significantly higher in patients with RPI (P UTI than ESR and CRP. Using a cut-off value of 0.85 ng/ml, PCT had the best performance, with sensitivity, specificity, and positive and negative predictive values of 89%, 97%, 96%, and 91% respectively. Serum PCT is a better marker than ESR, CRP, and leukocyte count for the early prediction of RPI in children with a first episode of UTI.

C-reactive protein and procalcitonin for the early detection of anastomotic leakage after elective colorectal surgery: pilot study in 100 patients.

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Lagoutte, N; Facy, O; Ravoire, A; Chalumeau, C; Jonval, L; Rat, P; Ortega-Deballon, P

2012-10-01

Anastomotic leakage is the most important complication after colorectal surgery. Its prognosis depends on its early diagnosis. C-reactive protein (CRP) has already shown its usefulness for the early detection of anastomotic leaks. Procalcitonin (PCT) is widely used in intensive care units and is more expensive, but its usefulness in the postoperative period of digestive surgery is not well established. Between May 2010 and June 2011, 100 patients undergoing elective colorectal surgery were prospectively included in a database. CRP and PCT were measured before surgery and daily until postoperative day 4. All intraabdominal infections were considered as anastomotic leaks, regardless of their clinical impact and their management. The kinetics of PCT and CRP were recorded, as well as their accuracy for the detection of anastomotic fistula. The incidence of fistula was 13% and the overall mortality rate was 2%. Both CRP and PCT were significantly higher in patients with leakage. Areas under the receiver-operating characteristics (ROC) for CRP were higher than those for PCT each day. The best accuracy was obtained for CRP on postoperative day 4 (areas under the ROC curve were 0.869 for CRP and 0.750 for PCT). Procalcitonin is neither earlier nor more accurate than CRP for the detection of anastomotic leakage after elective colorectal surgery. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Role of inflammatory markers as predictors of laparotomy in patients presenting with acute abdomen.

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Dias, Brendan H; Rozario, Anthony P; Olakkengil, Santosh A

2015-10-01

There is a need for an ideal indicator of surgery in patients presenting with acute abdomen. Several markers have been analysed, but the search still continues as none have proven effective. This study aimed to analyse and compare the predictive value of plasma procalcitonin (PCT) strip test in patients presenting with acute abdomen and identify a useful cut-off value to differentiate patients that would benefit with surgery from those that require conservative management. A prospective study was conducted in the department of general surgery from June 2012 to June 2013. Plasma PCT was estimated by the semi-quantitative strip test. The levels of plasma PCT and other routinely used markers of inflammation were analysed and compared. Of the total of 58 patients, 44 patients (76%) were men with a mean age of 45 years. Forty patients required emergency surgical intervention. A plasma PCT value of >0.5 ng/mL at admission was 80% sensitive and 100% specific for predicting need for antibiotics in patients with acute abdomen that were managed conservatively. The mean plasma PCT value in the patients undergoing surgery (5.0-10.0 ng/mL) was significantly more than in those managed conservatively (0.5-2.0 ng/mL). Using receiver operating characteristic (ROC) curves a cut-off for plasma PCT of >5.0 ng/mL was 75% sensitive and 100% specific for considering surgical intervention in patients presenting with acute abdomen. Plasma PCT (value >5 ng/mL) could be used as an adjunct to clinical examination to predict requirement of surgery in patients presenting with acute abdomen. © 2015 Royal Australasian College of Surgeons.

Slags in a Large Variation Range of Oxygen Potential Based on the Ion and Molecule Coexistence Theory

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Yang, Xue-Min; Li, Jin-Yan; Zhang, Meng; Chai, Guo-Min; Zhang, Jian

2014-12-01

A thermodynamic model for predicting sulfide capacity of CaO-FeO-Fe2O3-Al2O3-P2O5 slags in a large variation range of oxygen potential corresponding to mass percentage of FetO from 1.88 to 55.50 pct, i.e., IMCT- model, has been developed by coupling with the deduced desulfurization mechanism of the slags based on the ion and molecule coexistence theory (IMCT). The developed IMCT- model has been verified through comparing the determined sulfide capacity after Ban-ya et al.[20] with the calculated by the developed IMCT- model and the calculated by the reported sulfide capacity models such as the KTH model. Mass percentage of FetO as 6.75 pct corresponding to the mass action concentration of FetO as 0.0637 or oxygen partial as 2.27 × 10-6 Pa is the criterion for distinguishing reducing and oxidizing zones for the slags. Sulfide capacity of the slags in reducing zone is controlled by reaction ability of CaO regardless of slag oxidization ability. However, sulfide capacity of the slags in oxidizing zone shows an obvious increase tendency with the increasing of slag oxidization ability. Sulfide capacity of the slags in reducing zone keeps almost constant with variation of the simplified complex basicity (pct CaO)/((pct Al2O3) + (pct P2O5)), or optical basicity, or the mass action concentration ratios of N FeO/ N CaO, , , and . Sulfide capacity of the slags in oxidizing zone shows an obvious increase with the increasing of the simplified complex basicity (pct CaO)/((pct Al2O3) + (pct P2O5)) or optical basicity, or the aforementioned mass action concentration ratios. Thus, the aforementioned mass action concentration ratios and the corresponding mass percentage ratios of various iron oxides to basic oxide CaO are recommended to represent the comprehensive effect of various iron oxides and basic oxide CaO on sulfide capacity of the slags.

Nickel Ore Dispersion Evaluation and Consequences in Flotation Process

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de São José, Fábio; Imbelloni, Alaine Moreira; Nogueira, Francielle Câmara; Pereira, Carlos Alberto

2016-04-01

Nickel ore dispersion before flotation using different reagents was investigated on a bench scale to improve metallurgical recovery and selectivity. The nickel ore had a content of 0.8 pct nickel and 14.5 pct MgO. A positive linear correlation between MgO and Ni was found. Carboxy methyl cellulose, both pure and combined with Na2CO3, was the best dispersant used. The most efficient collector was potassium amyl xanthate combined with mercaptobenzothiazole, and the addition of xanthate was decisive for this good result because it is normally more stable in the pH range used in the tests. A pH change from 7 to 9 resulted in a metal recovery increase of 49.3 pct, together with an increase of 6.25 pct of MgO in the concentrate.

Pumpkin Fruit Influence on Calves’ Growth

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A. SHIMKUS

2014-07-01

Full Text Available Pumpkin provides a valuable source of carotenoids and ascorbic acid which have major roles in nutrition as provitamin A and as an antioxidant respectively. Carotenoids are a source of vitamin A, and β-carotene present in pumpkin is converted to vitamin A in the body. Pumpkins’ biomass is distinguished for having antioxidant and phytobiotic characteristics.The aim of our research is to analyse pumpkin fruit (Cucurbita maxima D. flours’ influence upon calves growth, intestinal microflora, digestibility of rations’ nutrients and health. In pursuance of this aim two groups of 1-month-old Lithuanian Black and White breeds’ heifers were constituted, 10 animals per group: control and experimental. The heifers were fed by the same feeding plan and grown in equal conditions. Except for experimental groups’ animals, each of them was additionally given 120g of pumpkin fruits’ flour with their days’ ration.The results of this research showed that calves which were additionally given pumpkin fruits‘ flour had grown more rapidly. After six months of the research the weight of experimental groups‘ heifers was 9,2 kg or 5,34 pct. bigger than the weight of control groups‘ heifers. Pumpkin fruits‘ flour distinguished for phytobiotic activity in calves‘ intestine, it stimulated the increase of lacto- and bifidobacteria. After four months of the research there were 63,6 pct. (P<0,001 more lactobacteria and 19,3 pct. (P<0,01 more bifidobacteria in the faeces of heifers that were additionally given pumpkin fruits‘ flour comparing to heifers that were not given it. After 6 months of the research respectively there were 10,7 pct. and 34,0 pct. more of lacto- and bifidobacteria. Besides that, pumpkin fruits‘ flour improved digestibility of rations‘ nutrients. Digestibility of dry matter increased by 1,9 pct., organic matter – 2,3 pct., fat – 1,6 pct., proteins – 3,07 pct. (P>0,05. Morphological blood indexes of both calves groups

Fast shading correction for cone beam CT in radiation therapy via sparse sampling on planning CT.

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Shi, Linxi; Tsui, Tiffany; Wei, Jikun; Zhu, Lei

2017-05-01

The image quality of cone beam computed tomography (CBCT) is limited by severe shading artifacts, hindering its quantitative applications in radiation therapy. In this work, we propose an image-domain shading correction method using planning CT (pCT) as prior information which is highly adaptive to clinical environment. We propose to perform shading correction via sparse sampling on pCT. The method starts with a coarse mapping between the first-pass CBCT images obtained from the Varian TrueBeam system and the pCT. The scatter correction method embedded in the Varian commercial software removes some image errors but the CBCT images still contain severe shading artifacts. The difference images between the mapped pCT and the CBCT are considered as shading errors, but only sparse shading samples are selected for correction using empirical constraints to avoid carrying over false information from pCT. A Fourier-Transform-based technique, referred to as local filtration, is proposed to efficiently process the sparse data for effective shading correction. The performance of the proposed method is evaluated on one anthropomorphic pelvis phantom and 17 patients, who were scheduled for radiation therapy. (The codes of the proposed method and sample data can be downloaded from https://sites.google.com/view/linxicbct) RESULTS: The proposed shading correction substantially improves the CBCT image quality on both the phantom and the patients to a level close to that of the pCT images. On the phantom, the spatial nonuniformity (SNU) difference between CBCT and pCT is reduced from 74 to 1 HU. The root of mean square difference of SNU between CBCT and pCT is reduced from 83 to 10 HU on the pelvis patients, and from 101 to 12 HU on the thorax patients. The robustness of the proposed shading correction is fully investigated with simulated registration errors between CBCT and pCT on the phantom and mis-registration on patients. The sparse sampling scheme of our method successfully

The potential biomarkers in predicting pathologic response of breast cancer to three different chemotherapy regimens: a case control study

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Xu Chaoyang

2009-07-01

Full Text Available Abstract Background Preoperative chemotherapy (PCT has become the standard of care in locally advanced breast cancer. The identification of patient-specific tumor characteristics that can improve the ability to predict response to therapy would help optimize treatment, improve treatment outcomes, and avoid unnecessary exposure to potential toxicities. This study is to determine whether selected biomarkers could predict pathologic response (PR of breast tumors to three different PCT regimens, and to identify a subset of patients who would benefit from a given type of treatment. Methods 118 patients with primary breast tumor were identified and three PCT regimens including DEC (docetaxel+epirubicin+cyclophosphamide, VFC (vinorelbine/vincristine+5-fluorouracil+cyclophosphamide and EFC (epirubicin+5-fluorouracil+cyclophosphamide were investigated. Expression of steroid receptors, HER2, P-gp, MRP, GST-pi and Topo-II was evaluated by immunohistochemical scoring on tumor tissues obtained before and after PCT. The PR of breast carcinoma was graded according to Sataloff's classification. Chi square test, logistic regression and Cochran-Mantel-Haenszel assay were performed to determine the association between biomarkers and PR, as well as the effectiveness of each regimen on induction of PR. Results There was a clear-cut correlation between the expression of ER and decreased PR to PCT in all three different regimens (p p Conclusion ER is an independent predictive factor for PR to PCT regimens including DEC, VFC and EFC in primary breast tumors, while HER2 is only predictive for DEC regimen. Expression of PgR, Topo-II, P-gp, MRP and GST-pi are not predictive for PR to any PCT regimens investigated. Results obtained in this clinical study may be helpful for the selection of appropriate treatments for breast cancer patients.

Preparation, mechanical strengths, and thermal

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Inoue, A.; Furukawa, S.; Hagiwara, M.; Masumoto, T.

1987-05-01

Ni-based amorphous wires with good bending ductility have been prepared for Ni75Si8B17 and Ni78P12B10 alloys containing 1 to 2 at. pct Al or Zr by melt spinning in rotating water. The enhancement of the wire-formation tendency by the addition of Al has been clarified to be due to the increase in the stability of the melt jet through the formation of a thin A12O3 film on the outer surface. The maximum wire diameter is about 190 to 200 μm for the Ni-Si (or P)-B-Al alloys and increases to about 250 μm for the Ni-Si-B-Al-Cr alloys containing 4 to 6 at. pct Cr. The tensile fracture strength and fracture elongation are 2730 MPa and 2.9 pct for (Ni0.75Si0.08B0.17 99Al1) wire and 2170 MPa and 2.4 pct for (Ni0.78P0.12B0.1)99Al1 wire. These wires exhibit a fatigue limit under dynamic bending strain in air with a relative humidity of 65 pct; this limit is 0.50 pct for a Ni-Si-B-Al wire, which is higher by 0.15 pct than that of a Fe75Si10B15 amorphous wire. Furthermore, the Ni-base wires do not fracture during a 180-deg bending even for a sample annealed at temperatures just below the crystallization temperature, in sharp contrast to high embrittlement tendency for Fe-base amorphous alloys. Thus, the Ni-based amorphous wires have been shown to be an attractive material similar to Fe- and Co-based amorphous wires because of its high static and dynamic strength, high ductility, high stability to thermal embrittlement, and good corrosion resistance.

TU-A-9A-10: Verification of Photoacoustic Computed Tomography Perfusion Imaging Using DCE-CT

International Nuclear Information System (INIS)

Roth, A; Krutulis, M; Verleker, A; Stantz, K

2014-01-01

Purpose: We propose to verify quantifiable perfusion information generated by a Photoacoustic Computed Tomography (PCT) scanner using Dynamic Contrast-Enhanced CT (DCE-CT), and to investigate physicsbased models of acoustic properties of tissue and photon transport to improve quantification. These corrections first necessitate a skin identifying algorithms to reduce speed-of-sound blurring and empirical photon correction methods. Methods: Xenograft mice (n=5) of breast cancer was imaged using DCE-CT which was followed by DCE-PCT. To obtain CT perfusion data, each mouse was i.v. injected (0.2mL Isovue @0.5mL/min) and subsequent radio-opaque time curves fit to a 2-compartmental model on a voxel-wise basis. For DCE-PCT, different concentrations of ICG (250, 125, and 62.5 micro-Molar) were injected at the same rate, but also acquired at different sampling rates (3, 6, and 12 seconds). The time intensity curves from PCT were fit to a 1-compartmental model on a voxel by voxel basis. The images were coregistered (Oncentra) based on the structural similarities of the tumor vasculature after which we compared both the contrastenhanced dynamics and the vascular physiology. Results: Moderate to high doses of ICG impact the washin phase of the PCT contrast due to photon losses as a function of depth. A semi-automatic algorithm has been developed to identify the skin margin, and subsequent MC and empirical models of photon transport and variations in speed-of-sound are being evaluated. Conclusion: From our results we find that there is a need to apply photon and speed-of-sound corrections to our PCT data to improve the quantifiable image data at depth in the tumor for PCT. The dose and injection rate may help in reducing large systematic effects. Our project is partially funded by a NIH SBIR grant

Procalcitonin and C-reactive protein as early markers of anastomotic leak after laparoscopic colorectal surgery within an enhanced recovery after surgery (ERAS) program.

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Muñoz, José Luis; Alvarez, María Oliva; Cuquerella, Vicent; Miranda, Elena; Picó, Carlos; Flores, Raquel; Resalt-Pereira, Marta; Moya, Pedro; Pérez, Ana; Arroyo, Antonio

2018-03-08

C-reactive protein (CRP) and procalcitonin (PCT) have been described as good predictors of anastomotic leak after colorectal surgery, obtaining the highest diagnostic accuracy on the 5th postoperative day. However, if an enhanced recovery after surgery (ERAS) program is performed, early predictors are needed in order to ensure a safe and early discharge. The aim of this study was to investigate the efficacy of CRP, PCT, and white blood cell (WBC) count determined on first postoperative days, in predicting septic complications, especially anastomotic leak, after laparoscopic colorectal surgery performed within an ERAS program. We conducted a prospective study including 134 patients who underwent laparoscopic colorectal surgery within an ERAS program between 2015 and 2017. The primary endpoint investigated was anastomotic leak. CRP, PCT, and WBC count were determined in the blood sample extracted on postoperative day 1 (POD 1), POD 2 and POD 3. Anastomotic leak (AL) was detected in 6 patients (4.5%). Serum levels of CRP and PCT, but not WBC, determined on POD 1, POD 2, and POD 3 were significantly higher in patients who had AL in the postoperative course. Using ROC analysis, the best AUC of the CRP and PCT levels was on POD 3 (0.837 and 0.947, respectively). A CRP cutoff level at 163 mg/l yielded 85% sensitivity, 80% specificity, and 99% negative predictive value (NPV). A PCT cutoff level at 2.5 ng/ml achieved 85% sensitivity, 95% specificity, 44% positive predictive value, and 99% NPV. CRP and PCT are relevant markers for detecting postoperative AL after laparoscopic colorectal surgery. Furthermore, they can ensure an early discharge with a low probability of AL when an ERAS program is performed.

Cell-Free DNA, High-Mobility Group Box-1, and Procalcitonin Concentrations in Dogs With Gastric Dilatation–Volvulus Syndrome

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Roberta Troia

2018-04-01

Full Text Available Canine gastric dilatation–volvulus (GDV is a life-threatening disease characterized by extensive tissue ischemia, tissue hypoperfusion, and systemic inflammation. Biomarkers that better reflect the severity of gastric necrosis and systemic inflammation would aid clinicians in the management of these patients. This study aimed to investigate the prognostic significance of cell-free DNA (cfDNA, high-mobility group box-1 (HMGB1, and procalcitonin (PCT in dogs with GDV. Concentrations of cfDNA, HMGB1, and PCT were measured in citrated plasma samples collected from 29 dogs with GDV at hospital admission. Additional data collected included baseline lactate concentrations, APPLEfast score, evidence of gastric necrosis, occurrence of postoperative complications, and outcome. Twenty-four healthy dogs were sampled as controls. Continuous variables between groups were compared with the Mann–Whitney U and correlations between continuous variables were assessed by calculation of Spearman’s correlation coefficient. Alpha was set at 0.05. Dogs with GDV had significantly greater concentrations of cfDNA, HMGB1, and PCT compared to controls (P = 0.0009, P = 0.004, and P = 0.009, respectively. PCT concentrations were significantly higher in non-survivors compared to survivors (P = 0.008. Dogs with gastric necrosis had significantly greater lactate concentrations compared to dogs without gastric necrosis (P = 0.0005. The APPLEfast score was not prognostic. Lactate and PCT concentrations were moderately, positively correlated (rs 0.51, P = 0.0005. Concentrations of the inflammatory biomarkers cfDNA, HMGB1, and PCT are increased in canine GDV. Only lactate and PCT concentrations were prognostic in this population of GDV dogs and were predictive of the presence of gastric necrosis and of non-survival to hospital discharge, respectively.

Cell-Free DNA, High-Mobility Group Box-1, and Procalcitonin Concentrations in Dogs With Gastric Dilatation-Volvulus Syndrome.

Science.gov (United States)

Troia, Roberta; Giunti, Massimo; Calipa, Stefano; Goggs, Robert

2018-01-01

Canine gastric dilatation-volvulus (GDV) is a life-threatening disease characterized by extensive tissue ischemia, tissue hypoperfusion, and systemic inflammation. Biomarkers that better reflect the severity of gastric necrosis and systemic inflammation would aid clinicians in the management of these patients. This study aimed to investigate the prognostic significance of cell-free DNA (cfDNA), high-mobility group box-1 (HMGB1), and procalcitonin (PCT) in dogs with GDV. Concentrations of cfDNA, HMGB1, and PCT were measured in citrated plasma samples collected from 29 dogs with GDV at hospital admission. Additional data collected included baseline lactate concentrations, APPLE fast score, evidence of gastric necrosis, occurrence of postoperative complications, and outcome. Twenty-four healthy dogs were sampled as controls. Continuous variables between groups were compared with the Mann-Whitney U and correlations between continuous variables were assessed by calculation of Spearman's correlation coefficient. Alpha was set at 0.05. Dogs with GDV had significantly greater concentrations of cfDNA, HMGB1, and PCT compared to controls ( P  = 0.0009, P  = 0.004, and P  = 0.009, respectively). PCT concentrations were significantly higher in non-survivors compared to survivors ( P  = 0.008). Dogs with gastric necrosis had significantly greater lactate concentrations compared to dogs without gastric necrosis ( P  = 0.0005). The APPLE fast score was not prognostic. Lactate and PCT concentrations were moderately, positively correlated ( r s 0.51, P  = 0.0005). Concentrations of the inflammatory biomarkers cfDNA, HMGB1, and PCT are increased in canine GDV. Only lactate and PCT concentrations were prognostic in this population of GDV dogs and were predictive of the presence of gastric necrosis and of non-survival to hospital discharge, respectively.

Cell-Free DNA, High-Mobility Group Box-1, and Procalcitonin Concentrations in Dogs With Gastric Dilatation–Volvulus Syndrome

Science.gov (United States)

Troia, Roberta; Giunti, Massimo; Calipa, Stefano; Goggs, Robert

2018-01-01

Canine gastric dilatation–volvulus (GDV) is a life-threatening disease characterized by extensive tissue ischemia, tissue hypoperfusion, and systemic inflammation. Biomarkers that better reflect the severity of gastric necrosis and systemic inflammation would aid clinicians in the management of these patients. This study aimed to investigate the prognostic significance of cell-free DNA (cfDNA), high-mobility group box-1 (HMGB1), and procalcitonin (PCT) in dogs with GDV. Concentrations of cfDNA, HMGB1, and PCT were measured in citrated plasma samples collected from 29 dogs with GDV at hospital admission. Additional data collected included baseline lactate concentrations, APPLEfast score, evidence of gastric necrosis, occurrence of postoperative complications, and outcome. Twenty-four healthy dogs were sampled as controls. Continuous variables between groups were compared with the Mann–Whitney U and correlations between continuous variables were assessed by calculation of Spearman’s correlation coefficient. Alpha was set at 0.05. Dogs with GDV had significantly greater concentrations of cfDNA, HMGB1, and PCT compared to controls (P = 0.0009, P = 0.004, and P = 0.009, respectively). PCT concentrations were significantly higher in non-survivors compared to survivors (P = 0.008). Dogs with gastric necrosis had significantly greater lactate concentrations compared to dogs without gastric necrosis (P = 0.0005). The APPLEfast score was not prognostic. Lactate and PCT concentrations were moderately, positively correlated (rs 0.51, P = 0.0005). Concentrations of the inflammatory biomarkers cfDNA, HMGB1, and PCT are increased in canine GDV. Only lactate and PCT concentrations were prognostic in this population of GDV dogs and were predictive of the presence of gastric necrosis and of non-survival to hospital discharge, respectively. PMID:29686994

Peripapillary Pachychoroid in Nonarteritic Anterior Ischemic Optic Neuropathy

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Nagia, Lina; Huisingh, Carrie; Johnstone, John; Kline, Lanning B.; Clark, Mark; Girard, Michael J. A.; Mari, Jean Martial; Girkin, Christopher A.

2016-01-01

Purpose This study examined the peripapillary choroidal thickness (PCT) in nonarteritic ischemic optic neuropathy (NAION) in comparison to contralateral eyes and normal eyes. Methods We used enhanced depth imaging spectral-domain optical coherence tomography to image the optic nerve head of 20 NAION, 10 contralateral eyes, and 102 normal eyes. Following compensation, the scans were manually delineated to identify relevant surfaces including Bruch's membrane opening (BMO), Bruch's membrane, and anterior sclera. The PCT was defined as the measurement between Bruch's membrane and the anterior sclera and was measured at increasing distance from BMO. Models adjusted for age, BMO area, and axial length were used to compare the mean PCT between NAION and normal eyes, and contralateral eyes and normal eyes. Paired t-tests were used to compare the PCT between NAION and contralateral eyes. Results The mean PCT was thicker in NAION and contralateral eyes when compared with normal eyes at all distances from BMO (P < 0.001). The PCT was not significantly thicker in contralateral eyes when compared with affected NAION eyes. Choroidal thickness was thinnest in the inferior quadrant in all eyes regardless of the group. Conclusions Increased peripapillary choroidal thickness was noted in both NAION and contralateral eyes. The thicker choroid may be an associated feature or a result of the disorder. Although further longitudinal study is required to determine causation, these findings may suggest that a thickened peripapillary choroid may be a component of the disk-at-risk clinical phenotype. PMID:27583829

Diagnosis and prediction of periodontally compromised teeth using a deep learning-based convolutional neural network algorithm.

Science.gov (United States)

Lee, Jae-Hong; Kim, Do-Hyung; Jeong, Seong-Nyum; Choi, Seong-Ho

2018-04-01

The aim of the current study was to develop a computer-assisted detection system based on a deep convolutional neural network (CNN) algorithm and to evaluate the potential usefulness and accuracy of this system for the diagnosis and prediction of periodontally compromised teeth (PCT). Combining pretrained deep CNN architecture and a self-trained network, periapical radiographic images were used to determine the optimal CNN algorithm and weights. The diagnostic and predictive accuracy, sensitivity, specificity, positive predictive value, negative predictive value, receiver operating characteristic (ROC) curve, area under the ROC curve, confusion matrix, and 95% confidence intervals (CIs) were calculated using our deep CNN algorithm, based on a Keras framework in Python. The periapical radiographic dataset was split into training (n=1,044), validation (n=348), and test (n=348) datasets. With the deep learning algorithm, the diagnostic accuracy for PCT was 81.0% for premolars and 76.7% for molars. Using 64 premolars and 64 molars that were clinically diagnosed as severe PCT, the accuracy of predicting extraction was 82.8% (95% CI, 70.1%-91.2%) for premolars and 73.4% (95% CI, 59.9%-84.0%) for molars. We demonstrated that the deep CNN algorithm was useful for assessing the diagnosis and predictability of PCT. Therefore, with further optimization of the PCT dataset and improvements in the algorithm, a computer-aided detection system can be expected to become an effective and efficient method of diagnosing and predicting PCT.

Possible ecological risk of two pharmaceuticals diclofenac and paracetamol demonstrated on a model plant Lemna minor.

Science.gov (United States)

Kummerová, Marie; Zezulka, Štěpán; Babula, Petr; Tříska, Jan

2016-01-25

Lemna minor is often used in environmental risk assessment and it can be supposed that usually evaluated parameters will be reliable even for assessing the risk of pharmaceuticals. Subtle changes in duckweed plant number, biomass production, and leaf area size induced by 10-day-exposure to diclofenac (DCF) and paracetamol (PCT) (0.1, 10, and 100 μg/L), excepting 100 μg/L DCF, are in contrast with considerable changes on biochemical and histochemical level. Both drugs caused a decrease in content of photosynthetic pigments (by up to 50%), an increase in non-photochemical quenching (by 65%) and decrease in relative chlorophyll fluorescence decay values (by up to 90% with DCF). Both DCF and especially PCT increased amount of reactive nitrogen and oxygen species in roots. DCF-induced effects included mainly increased lipid peroxidation (by 78%), disturbation in membrane integrity and lowering both oxidoreductase and dehydrogenase activities (by 30%). PCT increased the content of soluble proteins and phenolics. Higher concentrations of both DCF and PCT increased the levels of oxidised ascorbate (by 30%) and oxidised thiols (by up to 84% with DCF). Glutathion-reductase activity was elevated by both pharmaceuticals (nearly by 90%), glutathion-S-transferase activity increased mainly with PCT (by 22%). The early and sensitive indicators of DCF and PCT phytotoxicity stress in duckweed are mainly the changes in biochemical processes, connected with activation of defense mechanisms against oxidative stress. Copyright © 2015 Elsevier B.V. All rights reserved.

Monitor hemoglobin concentration and oxygen saturation in living mouse tail using photoacoustic CT scanner

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Liu, Bo; Kruger, Robert; Reinecke, Daniel; Stantz, Keith M.

2010-02-01

Purpose: The purpose of this study is to use PCT spectroscopy scanner to monitor the hemoglobin concentration and oxygen saturation change of living mouse by imaging the artery and veins in a mouse tail. Materials and Methods: One mouse tail was scanned using the PCT small animal scanner at the isosbestic wavelength (796nm) to obtain its hemoglobin concentration. Immediately after the scan, the mouse was euthanized and its blood was extracted from the heart. The true hemoglobin concentration was measured using a co-oximeter. Reconstruction correction algorithm to compensate the acoustic signal loss due to the existence of bone structure in the mouse tail was developed. After the correction, the hemoglobin concentration was calculated from the PCT images and compared with co-oximeter result. Next, one mouse were immobilized in the PCT scanner. Gas with different concentrations of oxygen was given to mouse to change the oxygen saturation. PCT tail vessel spectroscopy scans were performed 15 minutes after the introduction of gas. The oxygen saturation values were then calculated to monitor the oxygen saturation change of mouse. Results: The systematic error for hemoglobin concentration measurement was less than 5% based on preliminary analysis. Same correction technique was used for oxygen saturation calculation. After correction, the oxygen saturation level change matches the oxygen volume ratio change of the introduced gas. Conclusion: This living mouse tail experiment has shown that NIR PCT-spectroscopy can be used to monitor the oxygen saturation status in living small animals.

Relationship of neutrophil gelatinase-associated lipocalin (NGAL) and procalcitonin levels with the presence and severity of the preeclampsia.

Science.gov (United States)

Artunc-Ulkumen, Burcu; Guvenc, Yesim; Goker, Asli; Gozukara, Ceyhun

2015-11-01

The aim of the present study was to evaluate changes in maternal serum neutrophil gelatinase-associated lipocalin (NGAL) and procalcitonin (PCT) concentrations in preeclampsia. This case-control study consisted of 40 preeclamptic and 40 healthy singleton pregnancies matched for age and body mass index. Serum NGAL and PCT levels were compared between the groups. Diagnostic performance and clinical association of these markers were evaluated. NGAL and PCT concentrations were significantly higher in preeclamptic group (p preeclampsia. There were significant positive correlation between these markers and mean arterial pressure (MAP) and spot urine protein excretion. There was negative correlation between NGAL and apgar scores and fetal birth weight. Pregnancies with higher NGAL (OR: 4.89; 95% CI: 1.81-13.21) and higher PCT (OR: 6.67; 95% CI: 2.44-18.21) concentrations had higher risk for preeclampsia. NGAL and PCT may be potential biomarkers for preeclampsia. Their levels increase significantly in preeclampsia and they are related to the severity of the disease. These results are in agreement with the generalized endothelial damage and persistant inflammatory status in preeclampsia. NGAL may also be an indicator for adverse neonatal outcomes with decreased placental hypoperfusion.

Effects of Poly(cyclohexanedimethylene terephthalate on Microstructures, Crystallization Behavior and Properties of the Poly(ester ether Elastomers

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Yi-Cheng Feng

2017-06-01

Full Text Available To understand the role of molecular structure on the crystallization behavior of copolyester in thermoplastic poly(ether ester elastomers (TPEEs, series of poly(butylene-co-1,4-cyclohexanedimethylene terephthalate (P(BT-co-CT-b-poly(tetramethylene glycol (PTMG are synthesized through molten polycondensation process. The effects of poly(cyclohexanedimethylene terephthalate (PCT content on the copolymer are investigated by Fourier transform infrared spectroscopy (FT-IR, 1H and 13C nuclear magnetic resonance (NMR, gel permeation chromatographs (GPC, wide-angle X-ray diffraction (WAXD, differential scanning calorimetry (DSC, thermogravimetric analysis (TGA, mechanical, and visible light transmittance tests. FT-IR and NMR results confirm the incorporation of PCT onto the copolymer. WAXD and DSC indicate that the crystalline structure of the copolymers changed from α-PBT lattice to trans-PCT lattice when the molar fraction of PCT (MPCT is above 30%, while both crystallization and melting temperatures reach the minima. An increase in MPCT led to an increase in the number sequence length of PCT, the thermal stability and the visible light transmittance of the copolymer, but to a slight decrease in tensile strength and elastic modulus.

Point-of-care procalcitonin test to reduce antibiotic exposure in patients hospitalized with acute exacerbation of COPD

DEFF Research Database (Denmark)

Corti, Caspar; Fally, Markus; Fabricius-Bjerre, Andreas

2016-01-01

BACKGROUND: This study was conducted to investigate whether point-of-care (POC) procalcitonin (PCT) measurement can reduce redundant antibiotic treatment in patients hospitalized with acute exacerbation of COPD (AECOPD). METHODS: One-hundred and twenty adult patients admitted with AECOPD were...... in the PCT-arm vs 8.5 (IQR 1-11) days in the control arm (P=0.0169, Wilcoxon) for the intention-to-treat population. The proportion of patients using antibiotics for ≥5 days within the 28-day follow-up was 41.9% (PCT-arm) vs 67.2% (P=0.006, Fisher's exact) in the intention-to-treat population. For the per...... no apparent difference. CONCLUSION: Our study shows that the implementation of a POC PCT-guided algorithm can be used to substantially reduce antibiotic exposure in patients hospitalized with AECOPD, with no apparent harm....

Waste management technology development and demonstration programs at Brookhaven National Laboratory

Science.gov (United States)

Kalb, Paul D.; Colombo, Peter

1991-01-01

Two thermoplastic processes for improved treatment of radioactive, hazardous, and mixed wastes were developed from bench scale through technology demonstration: polyethylene encapsulation and modified sulfur cement encapsulation. The steps required to bring technologies from the research and development stage through full scale implementation are described. Both systems result in durable waste forms that meet current Nuclear Regulatory Commission and Environmental Protection Agency regulatory criteria and provide significant improvements over conventional solidification systems such as hydraulic cement. For example, the polyethylene process can encapsulate up to 70 wt pct. nitrate salt, compared with a maximum of about 20 wt pct. for the best hydraulic cement formulation. Modified sulfur cement waste forms containing as much as 43 wt pct. incinerator fly ash were formulated, whereas the maximum quantity of this waste in hydraulic cement is 16 wt pct.

A comparison of high-mobility group-box 1 protein, lipopolysaccharide-binding protein and procalcitonin in severe community-acquired infections and bacteraemia: a prospective study

DEFF Research Database (Denmark)

Gaïni, Shahin; Koldkjaer, Ole G; Møller, Holger J

2008-01-01

manner. Demographic data, comorbidity, routine biochemistry, microbiological data, infection focus, severity score and mortality on day 28 were recorded. Plasma and serum were sampled within 24 hours after admission. Levels of all studied markers (HMGB1, LBP, PCT, IL-6, C-reactive protein, white blood...... patients compared with nonbacteraemic patients (P white blood cell count and neutrophils (P ... (HMGB1, LBP, PCT, IL-6) and infection markers (C-reactive protein, white blood cell count, neutrophils) were elevated among bacteraemic patients. PCT performed best as a diagnostic test marker for bacteraemia. Udgivelsesdato: 2007-null...

Effects of Electromagnetic Stirring on the Microstructure and High-Temperature Mechanical Properties of a Hyper-eutectic Al-Si-Cu-Ni Alloy

Science.gov (United States)

Jang, Youngsoo; Choi, Byounghee; Kang, Byungkeun; Hong, Chun Pyo

2015-02-01

A liquid treatment method by electromagnetic stirring was applied to a hyper-eutectic Al-15wt pctSi-4wt pctCu-3wt pctNi alloy for the piston manufacturing with diecasting process in order to improve high-temperature mechanical properties of the piston heads. The mechanical properties, such as hardness, high-temperature tensile stress, thermal expansion, and high-temperature relative wear resistance, were estimated using the specimens taken from the liquid-treated diecast products, and the results were compared with those of a conventional metal-mold-cast piston.

Procalcitonin is not sufficiently reliable to be the sole marker of neonatal sepsis of nosocomial origin

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Moro Serrano Manuel

2006-05-01

Full Text Available Abstract Background It has recently been suggested that serum procalcitonin (PCT is of value in the diagnosis of neonatal sepsis, with varying results. The aim of this prospective multicenter study was to assess the usefulness of PCT as a marker of neonatal sepsis of nosocomial origin. Methods One hundred infants aged between 4 and 28 days of life admitted to the Neonatology Services of 13 acute-care teaching hospitals in Spain over 1-year with clinical suspicion of neonatal sepsis of nosocomial origin were included in the study. Serum PCT concentrations were determined by a specific immunoluminometric assay. The reliability of PCT for the diagnosis of nosocomial neonatal sepsis at the time of suspicion of infection and at 12–24 h and 36–48 h after the onset of symptoms was calculated by receiver-operating characteristics (ROC curves. The Youden's index (sensitivity + specificity - 1 was used for determination of optimal cutoff values of the diagnostic tests in the different postnatal periods. Sensitivity, specificity, and the likelihood ratio of a positive and negative result with the 95% confidence interval (CI were calculated. Results The diagnosis of nosocomial sepsis was confirmed in 61 neonates. Serum PCT concentrations were significantly higher at initial suspicion and at 12–24 h and 36–48 h after the onset of symptoms in neonates with confirmed sepsis than in neonates with clinically suspected but not confirmed sepsis. Optimal PCT thresholds according to ROC curves were 0.59 ng/mL at the time of suspicion of sepsis (sensitivity 81.4%, specificity 80.6%; 1.34 ng/mL within 12–24 h of birth (sensitivity 73.7%, specificity 80.6%, and 0.69 ng/mL within 36–48 h of birth (sensitivity 86.5%, specificity 72.7%. Conclusion Serum PCT concentrations showed a moderate diagnostic reliability for the detection of nosocomial neonatal sepsis from the time of suspicion of infection. PCT is not sufficiently reliable to be the sole marker of

Experimental Study on GFRP Surface Cracks Detection Using Truncated-Correlation Photothermal Coherence Tomography

Science.gov (United States)

Wang, Fei; Liu, Junyan; Mohummad, Oliullah; Wang, Yang

2018-04-01

In this paper, truncated-correlation photothermal coherence tomography (TC-PCT) was used as a nondestructive inspection technique to evaluate glass-fiber reinforced polymer (GFRP) composite surface cracks. Chirped-pulsed signal that combines linear frequency modulation and pulse excitation was proposed as an excitation signal to detect GFRP composite surface cracks. The basic principle of TC-PCT and extraction algorithm of the thermal wave signal feature was described. The comparison experiments between lock-in thermography, thermal wave radar imaging and chirped-pulsed photothermal radar for detecting GFRP artificial surface cracks were carried out. Experimental results illustrated that chirped-pulsed photothermal radar has the merits of high signal-to-noise ratio in detecting GFRP composite surface cracks. TC-PCT as a depth-resolved photothermal imaging modality was employed to enable three-dimensional visualization of GFRP composite surface cracks. The results showed that TC-PCT can effectively evaluate the cracks depth of GFRP composite.

Procalcitonin and C-reactive protein as markers of bacterial infection in patients with solid tumours

DEFF Research Database (Denmark)

Diness, Laura V; Maraldo, Maja V; Mortensen, Christiane E

2014-01-01

INTRODUCTION: The diagnosis of bacterial infections in patients with solid tumours can be difficult as both the tumour and its treatment can cause symptoms and signs similar to those of infections. Many patients with solid tumours therefore receive antibiotic treatment without having a bacterial......, but with no signs of infection. RESULTS: Of the 41 admitted patients, 25 were classified as having an infection (either microbiologically or radioo-gically verified). Among the 25 cases with infection, PCT was within the normal range in 11 cases and only elevated in 14. As nearly half of the patients with infection...... had PCT within the normal range, PCT is not suited to exclude an infection. CRP was elevated in 20 patients out of the 25. CONCLUSION: PCT within the normal range cannot exclude an infection and does not appear to be superior to CRP to exclude an infection in patients with solid tumours. FUNDING...

Diagnostic Value of Procalcitonin Levels in Acute Mesenteric Ischemia

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Yunus Karaca

2015-09-01

Full Text Available Background: Acute mesenteric ischemia (AMI is a potentially fatal disease. Difficulties in diagnosis make it essential to find early biomarkers. Aims: This study investigated the diagnostic value of procalcitonin (PCT levels in AMI. Study Design: Animal experimentation. Methods: Rats were divided into six groups of six animals each. In the experimental group, an experimental ischemia model was established by clamping the superior mesenteric artery from the aortic outflow tract. Blood and tissue specimens were collected from rats in the experimental mesenteric ischemia model at 30 min and 2 and 6 h, and these were compared with specimens from the respective control groups. PCT levels were compared at 30 min and 2 and 6 h. Results: PCT levels were 185.3 pg/mL in the control group and 219.3 pg/mL in the study group, 199.6 pg/mL in the control group and 243.9 pg/mL in the study group, and 201.9 pg/mL in the control group and 286.9 pg/mL in the study group, respectively, at 30 minute, 2 and 6 hours. Significant differences were determined between 6-h control group and ischemia group PCT levels (p=0.005. Conclusion: The absence of a significant increase in PCT levels in the early period, while a significant difference was detected in the later period (6 h, shows that PCT levels rise late in mesenteric ischemia and can be a marker in the late period.

Inflammation biomarkers and mortality prediction in patients with type 2 diabetes (ZODIAC-27)

NARCIS (Netherlands)

Landman, Gijs W. D.; Kleefstra, Nanne; Groenier, Klaas H.; Bakker, Stephan J. L.; Groeneveld, Geert H.; Bilo, Henk J. G.; van Hateren, Kornelis J. J.

Background: C-reactive protein (CRP), procalcitonin (PCT) and pro-adrenomedullin (MR-proADM) are inflammation markers associated with long-term mortality risk. We compared the associations and predictive capacities of CRP, PCT and MR-proADM with cardiovascular and all-cause mortality in patients

Value of Perfusion CT, Transcranial Doppler Sonography, and Neurological Examination to Detect Delayed Vasospasm after Aneurysmal Subarachnoid Hemorrhage

International Nuclear Information System (INIS)

Kunze, E.; Raslan, F.; Stetter, Ch.; Lee, J.Y.; Solymosi, L.; Ernestus, R.I.; Vince, G.H.; Westermaier, Th.; Pham, M.; Solymosi, L.

2012-01-01

Background. If detected in time, delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) may be treated by balloon angioplasty or chemical vasospasmolysis in order to enhance cerebral blood flow (CBF) and protect the brain from ischemic damage. This study was conceived to compare the diagnostic accuracy of detailed neurological examination, Transcranial Doppler Sonography (TCD), and Perfusion-CT (PCT) to detect angiographic vasospasm. Methods. The sensitivity, specificity, positive and negative predictive values of delayed ischemic neurological deterioration (DIND), pathological findings on PCT-maps, and accelerations of the mean flow velocity (MVF) were calculated. Results. The accuracy of DIND to predict angiographic vasospasm was 0.88. An acceleration of MFV in TCD (>140 cm/s) had an accuracy of 0.64, positive PCT-findings of 0.69 with a higher sensitivity, and negative predictive value than TCD. Interpretation. Neurological assessment at close intervals is the most sensitive and specific parameter for cerebral vasospasm. PCT has a higher accuracy, sensitivity and negative predictive value than TCD. If detailed neurological evaluation is possible, it should be the leading parameter in the management and treatment decisions. If patients are not amenable to detailed neurological examination, PCT at regular intervals is a helpful tool to diagnose secondary vasospasm after aneurysmal SAH

The diagnostic value of procalcitonin, adenosine deaminase for tuberculous pleural effusions

International Nuclear Information System (INIS)

Sun Jia; Jing Xiufeng; Hui Fuxin

2010-01-01

Objective: To explore differential diagnostic value of procalcitonin (PCT), adenosine deaminase (ADA) in pleural fluid and serum for tuberculous pleural effusions. Methods: The concentrations of PCT and ADA both in serum and pleural fluid in one hundred and twenty-eight patients with pleural effusion were detected. These patients were divided into three groups. Fifty-two patients with tuberculous plueral effusion were composed of the tuberculous group. Twenty-two patients with parapneumonic effusion composed the pneumonic group and forty patients with malignant pleural effusion and fourteen patients with heart faliure composed of the control group. Results: There were no statistically significant differences in serum PCT among the three groups (P > 0.05). PCT of pleural fluid was significantly increased in tuberculous and parapneumonic groups compared to the control group (P < 0.05). ADA activities in tuberculous serum and pleural fluid were both higher than those in the parapneumonic and the control groups (P < 0.01). The ratio of ADA in pleural fluid and serum (P /S) was calculated. The diagnostic sensitivity and specificity of P /S (cut-off value 1.27) were 92.3% and 100% respectively for tuberculous pleural effusions calcuted by receiver operating curve. Conclusion: Combined measurements of PCT and ADA in pleural fluid are useful in diagnosing tuberculous pleural effusions. (authors)

BWR 1 % main recirculation line break LOCA tests, RUNs 917 and 918, without HPCS at ROSA-III program

International Nuclear Information System (INIS)

Suzuki, Mitsuhiro; Okazaki, Motoaki; Anoda, Yoshinari; Kumamaru, Hiroshige; Nakamura, Hideo; Yonomoto, Taisuke; Koizumi, Yasuo; Tasaka, Kanji

1988-07-01

In a case of small break loss-of-coolant accident (LOCA) at a boiling water reactor (BWR) system, it is important to lower the system pressure to cool down the reactor system by using either the high pressure core spray (HPCS) or the automatic depressurization system (ADS). The report presents characteristic test results of RUNs 918 and 917, which were performed at the rig-of-safety assessment (ROSA)-III program simulating a 1 % break BWR LOCA with an assumption of HPCS failure, and clarifies effects of the ADS delay time on a small break LOCA. The ROSA-III test facility simulates principal components of a BWR/6 system with volumetric scaling factor of 1/424. It is experimentally concluded that the ADS delay time shorter than 4 minutes results in a similar PCT as that in a standard case, in which the PCT is observed after actuation of the low pressure core spray (LPCS). And the ADS delay time longer than 4 minutes results in higher PCT than in the standard case. In the latter, the PCT depends on the ADS time, a 220 K higher PCT, for example, in a case of 10 minutes ADS delay compared with the standard case. (author) 52 refs. 299 figs

Impact of Oral Commensal Bacteria on Degradation of Periodontal Connective Tissue in Mice.

Science.gov (United States)

Irie, Koichiro; Tomofuji, Takaaki; Ekuni, Daisuke; Morita, Manabu; Shimazaki, Yoshihiro; Darveau, Richard P

2015-07-01

Innate and adaptive immunosurveillance mechanisms in response to the normal commensal bacteria can affect periodontal innate defense status. However, it is still unclear how commensal bacteria contribute to the inflammatory responses of junctional epithelium (JE) and periodontal connective tissue (PCT). The aim of the present study is to investigate the contribution of commensal bacteria on inflammatory responses in JE and PCT in mice. The periodontal tissue of germ-free (GF) and specific-pathogen-free (SPF) mice were compared at age 11 to 12 weeks (n = 6 per group). In this study, the number of neutrophils and expression of intercellular adhesion molecule (ICAM)-1, fibroblast growth factor receptor (FGFR)-1, matrix metalloproteinase (MMP)-1, and MMP-8 within the JE and the PCT are evaluated. The collagen density was also determined in PCT stained with picrosirius red (PSR). PSR staining combined with or without polarized light microscopy has been used to assess the organization and maturation of collagen matrix. In the present findings, the area of JE in SPF mice was significantly greater than that in GF mice (P bacteria induced a low-grade inflammatory state in JE and that such conditions may contribute to degradation of collagen in PCT in mice.

Application of Precipitate Free Zone Growth Kinetics to the β-Phase Depletion Behavior in a CoNiCrAlY Coating Alloy: An Analytical Approach

Science.gov (United States)

Chen, H.

2018-06-01

This paper concerns the β-phase depletion kinetics of a thermally sprayed free-standing CoNiCrAlY (Co-31.7 pct Ni-20.8 pct Cr-8.1 pct Al-0.5 pct Y, all in wt pct) coating alloy. An analytical β-phase depletion model based on the precipitate free zone growth kinetics was developed to calculate the β-phase depletion kinetics during isothermal oxidation. This approach, which accounts for the molar volume of the alloy, the interfacial energy of the γ/ β interface, and the Al concentration at γ/ γ + β boundary, requires the Al concentrations in the β-phase depletion zone as the input rather than the oxidation kinetics at the oxide/coating interface. The calculated β-phase depletion zones derived from the current model were compared with experimental results. It is shown that the calculated β-phase depletion zones using the current model are in reasonable agreement with those obtained experimentally. The constant compositional terms used in the model are likely to cause the discrepancies between the model predictions and experimental results. This analytical approach, which shows a reasonable correlation with experimental results, demonstrates a good reliability in the fast evaluation on lifetime prediction of MCrAlY coatings.

Evaluation of brain perfusion in Alzheimer disease with perfusion computed tomography and comparison to elderly patient without dementia.

Science.gov (United States)

Yildirim, Tülin; Karakurum Göksel, Başak; Demir, Şenay; Tokmak, Naime; Tan, Meliha

2016-04-19

The aim of this study was to evaluate perfusion computed tomography (PCT) findings in patients with Alzheimer disease and to compare them with those of patients without dementia. PCT was performed in 35 patients: 20 with Alzheimer disease (mean age, 69.7 ± 5.5 years) and 15 control subjects (mean age, 67.5 ± 3.5 years). Control subjects were elderly individuals with no cognitive problems who were admitted with headaches. All PCT examinations were performed on a 4-slice CT unit. The PCT analysis software program was used to calculate regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), regional time-to-peak (rTTP) values in the bilateral frontal, temporal, and occipital cortices, and bilateral lentiform nucleus. rCBF values in the bilateral frontal and temporal cortices and bilateral lentiform nucleus were significantly lower in the patients with Alzheimer disease than in the control subjects. There were no significant differences in rCBV values between Alzheimer disease and the control group. rTTP values in all cortical areas and bilateral lentiform nucleus were significantly higher in the patients with Alzheimer disease than in the control subjects. PCT is a rapid and reliable imaging modality for evaluating brain perfusion in Alzheimer disease.

Application of Precipitate Free Zone Growth Kinetics to the β-Phase Depletion Behavior in a CoNiCrAlY Coating Alloy: An Analytical Approach

Science.gov (United States)

Chen, H.

2018-03-01

This paper concerns the β-phase depletion kinetics of a thermally sprayed free-standing CoNiCrAlY (Co-31.7 pct Ni-20.8 pct Cr-8.1 pct Al-0.5 pct Y, all in wt pct) coating alloy. An analytical β-phase depletion model based on the precipitate free zone growth kinetics was developed to calculate the β-phase depletion kinetics during isothermal oxidation. This approach, which accounts for the molar volume of the alloy, the interfacial energy of the γ/β interface, and the Al concentration at γ/γ + β boundary, requires the Al concentrations in the β-phase depletion zone as the input rather than the oxidation kinetics at the oxide/coating interface. The calculated β-phase depletion zones derived from the current model were compared with experimental results. It is shown that the calculated β-phase depletion zones using the current model are in reasonable agreement with those obtained experimentally. The constant compositional terms used in the model are likely to cause the discrepancies between the model predictions and experimental results. This analytical approach, which shows a reasonable correlation with experimental results, demonstrates a good reliability in the fast evaluation on lifetime prediction of MCrAlY coatings.

Effect of Microstructure on Electrical Conductivity of Nickel-Base Superalloys

Science.gov (United States)

Nagarajan, Balasubramanian; Castagne, Sylvie; Annamalai, Swaminathan; Fan, Zheng; Chan, Wai Luen

2017-08-01

Eddy current spectroscopy is one of the promising non-destructive methods for residual stress evaluation along the depth of subsurface-treated nickel-base superalloys, but it is limited by its sensitivity to microstructure. This paper studies the influence of microstructure on the electrical conductivity of two nickel-base alloys, RR1000 and IN100. Different microstructures were attained using heat treatment cycles ranging from solution annealing to aging, with varying aging time and temperature. Eddy current conductivity was measured using conductivity probes of frequencies ranging between 1 and 5 MHz. Qualitative and quantitative characterization of the microstructure was performed using optical and scanning electron microscopes. For the heat treatment conditions between the solution annealing and the peak aging, the electrical conductivity of RR1000 increased by 6.5 pct, which is duly substantiated by the corresponding increase in hardness (12 pct) and the volume fraction of γ' precipitates (41 pct). A similar conductivity rise of 2.6 pct for IN100 is in agreement with the increased volume fraction of γ' precipitates (12.5 pct) despite an insignificant hardening between the heat treatment conditions. The observed results with RR1000 and IN100 highlight the sensitivity of electrical conductivity to the minor microstructure variations, especially the volume fraction of γ' precipitates, within the materials.

Procalcitonin for prediction of chorioamnionitis in preterm premature rupture of membranes.

Science.gov (United States)

Thornburg, Loralei L; Queenan, Ruthanne; Brandt-Griffith, Brianne; Pressman, Eva K

2016-01-01

To assess serum procalcitonin (PCT), a marker of monocyte activity, in predicting chorioamnionitis in preterm premature rupture of membranes (PPROM). Prospective cohort study in singleton gestation patients with PPROM between 2 2 + 0 to 3 3 + 6 weeks gestation. Two blood samples were taken - admission and delivery or diagnosis of clinical chorioamnionitis. Maternal serum PCT > 0.1 ng/mL was considered positive. Patients were divided into four groups: clinical evidence of chorioamnionitis confirmed by placental pathology (group C + P); pathological evidence of chorioamnionitis without clinical signs (group P); clinical signs only (group C); and patients without clinical or pathological findings (group N). Groups were compared to gestational age matched controls. Forty eight patients recruited, with 28 eligible for analysis: 10 in C + P group, 10 P group, 3 C group, and 5 N group. None of the control or PPROM patients had positive PCT on admission. At delivery, 3 of 10 group C + P and 4 of 10 group P had positive PCT. Maternal serum PCT sensitivity was 50% and specificity 55.6% for diagnosis of pathological chorioamnionitis. Maternal serum PCT is not detectable in PPROM patients at admission or in uncomplicated pregnant controls and is a poor predictor for clinical or pathological chorioamnionitis.

THE ROLE OF PROCALCITONIN IN BACTERIAL INFECTION RECOGNITION

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Lucija Gabršek

2001-12-01

Full Text Available Background. Early recognition of bacterial infection and antibiotic treatment are very important in critically ill patients. Procalcitonin (PCT is a marker of bacterial infections accompanied by systemic inflammatory response. Higher values were also noticed with parasitical and fungal infections, but PCT is normal in viral and systemic diseases. The aim of this study was to assess whether PCT is better marker for bacterial infections than C-reactive protein (CRP and if they have a prognostic value.Methods. 34 patients were included into our retrospective study. All of them had clinical or laboratory signs of infection at the first PCT determination. We measured PCT, CRP, erythrocyte sedimentation rate (SR and leukocyte count. On the base of microbiological results we divided patients into three groups. Group A had patients with sterile cultures, group B included the ones with negative blood cultures, but from other cultures causative agents were identified. The patients in group C had positive blood cultures. Retrospectively we studied PCT and CRP values among groups and among survivors and non survivors.Results. An average median value of PCT in group A was 8.9 ± 13.3 ng/ml, in group B 5.3 ± 9.3 ng/ml and in group C 21.0 ± 25.0 ng/ml. In group B, the average median value of PCT was significantly higher than in group C (p = 0.019, but that was not the case in group A (p = 0.23. The average median values of CRP were 129.9 ± 67.4 mg/l in group A, 104.3 ± 60.1 mg/l in group B and 117.4 ± 46.1 mg/l in group C. Between groups, differences of CRP values were not statistically significant. The average initial value of PCT in group of non survivors (8.9 ± 49 was not significantly higher then in group of survivors (3.14 ± 55.4 (p = 0.48. The average final value was significantly higher (p = 0.0013 in group of non survivors (13.1 ± 23.9 ng/l than in group of survivors (0.55 ± 7.3 ng/ml. In both groups the average initial values of CRP did not

76 FR 55807 - Novaluron; Pesticide Tolerances

Science.gov (United States)

2011-09-09

... observed at the same dose. Reproductive toxicity (decreases in epididymal sperm counts and increase age at... dose; additionally, reproductive effects (decreases in epididymal sperm counts and increased age at... most recent 6-7 years. EPA uses an average PCT for chronic dietary risk analysis. The average PCT...

Enduring effects of Preventive Cognitive Therapy in adults remitted from recurrent depression : A 10 year follow-up of a randomized controlled trial

NARCIS (Netherlands)

Bockting, C. L. H.; Smid, N. H.; Koeter, M. W. J.; Spinhoven, P.; Beck, A. T.; Schene, Aart H.

2015-01-01

Background: Prevention of recurrence is a challenge in the management of major depressive disorder (MDD). The long-term effects of Preventive Cognitive Therapy (PCT) in preventing recurrence in MDD are not known. Methods: A RCT comparing the addition of PCT to Treatment As Usual (TAU), versus TAU

78 FR 16505 - Prospective Grant of Exclusive License: Chimeric West Nile/Dengue Viruses

Science.gov (United States)

2013-03-15

... Grant of Exclusive License: Chimeric West Nile/Dengue Viruses AGENCY: Centers for Disease Control and.... Provisional Application 61/049,342, filed 4/30/2008, entitled ``Engineered, Chimeric West Nile/Dengue Viruses;'' PCT Application PCT/US2009/041824, filed 4/27/2009, entitled ``Engineered, Chimeric WN/Flavivirus as...

77 FR 68783 - Prospective Grant of Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus

Science.gov (United States)

2012-11-16

... Grant of Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus AGENCY: Centers for Disease..., filed 12/21/2007, entitled ``Development of Rift Valley Fever Virus Utilizing Reverse Genetics,'' US... (RVF) Viruses and Method of Use,'' PCT Application PCT/US2008/ 087023, filed 12/16/2008, entitled...

77 FR 68783 - Prospective Grant of Co-Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus

Science.gov (United States)

2012-11-16

... Grant of Co-Exclusive License: Veterinary Vaccines for Rift Valley Fever Virus AGENCY: Centers for... Valley Fever Virus Utilizing Reverse Genetics,'' US Provisional Application 61/042,987, filed 4/7/2008, entitled ``Recombinant Rift Valley Fever (RVF) Viruses and Method of Use,'' PCT Application PCT/US2008...

The Development and Application of the RAND Program Classification Tool. The RAND Toolkit, Volume 1

Science.gov (United States)

2014-01-01

service, reference DoD programs related to psycho - logical health and TBI, but the R-PCT can be applied to other content areas or organizations. Table...and provides a high-level description, comparison, or classification of programs. Furthermore, given its simple architecture , the R-PCT can be

Geometrical optimization of a particle tracking system for proton computed tomography

International Nuclear Information System (INIS)

Penfold, S.N.; Rosenfeld, A.B.; Schulte, R.W.; Sadrozinksi, H.-F.W.

2011-01-01

Proton computed tomography (pCT) is currently being developed as an imaging modality for improving the accuracy of treatment planning in proton therapy. A tracking telescope comprising eight planes of single-sided silicon strip detectors (SSDs) forms an integral part of our present pCT design. Due to the currently maximum available Si wafer size, the sensitive area of 9 cm × 18 cm of the pCT tracker requires each tracking plane to be composed of two individual SSDs, which creates potential reconstruction problems due to overlap or gaps of the sensitive SSD areas. Furthermore, the spacing of the tracking planes creates competing design requirements between compactness and spatial resolution. Two Monte Carlo simulations were performed to study the effect of tracking detector location on pCT image quality. It was found that a “shingled” detector design suppressed reconstruction artefacts and, for the spatial resolution of the current detector hardware, reconstructed spatial resolution was not improved with a tracking separation of greater than 8 cm.

Proton range shift analysis on brain pseudo-CT generated from T1 and T2 MR.

Science.gov (United States)

Pileggi, Giampaolo; Speier, Christoph; Sharp, Gregory C; Izquierdo Garcia, David; Catana, Ciprian; Pursley, Jennifer; Amato, Francesco; Seco, Joao; Spadea, Maria Francesca

2018-05-29

In radiotherapy, MR imaging is only used because it has significantly better soft tissue contrast than CT, but it lacks electron density information needed for dose calculation. This work assesses the feasibility of using pseudo-CT (pCT) generated from T1w/T2w MR for proton treatment planning, where proton range comparisons are performed between standard CT and pCT. MR and CT data from 14 glioblastoma patients were used in this study. The pCT was generated by using conversion libraries obtained from tissue segmentation and anatomical regioning of the T1w/T2w MR. For each patient, a plan consisting of three 18 Gy beams was designed on the pCT, for a total of 42 analyzed beams. The plan was then transferred onto the CT that represented the ground truth. Range shift (RS) between pCT and CT was computed at R 80 over 10 slices. The acceptance threshold for RS was according to clinical guidelines of two institutions. A γ-index test was also performed on the total dose for each patient. Mean absolute error and bias for the pCT were 124 ± 10 and -16 ± 26 Hounsfield Units (HU), respectively. The median and interquartile range of RS was 0.5 and 1.4 mm, with highest absolute value being 4.4 mm. Of the 42 beams, 40 showed RS less than the clinical range margin. The two beams with larger RS were both in the cranio-caudal direction and had segmentation errors due to the partial volume effect, leading to misassignment of the HU. This study showed the feasibility of using T1w and T2w MRI to generate a pCT for proton therapy treatment, thus avoiding the use of a planning CT and allowing better target definition and possibilities for online adaptive therapies. Further improvements of the methodology are still required to improve the conversion from MRI intensities to HUs.

Preparation, mechanical strengths, and thermal stability of Ni-Si-B and Ni-P-B amorphous wires

International Nuclear Information System (INIS)

Inoue, A.; Furukawa, S.; Hagiwara, M.; Masumoto, T.

1987-01-01

Ni-based amorphous wires with good bending ductility have been prepared for Ni/sub 75/Si/sub 8/B/sub 17/ and Ni/sub 78/P/sub 12/B/sub 10/ alloys containing 1 to 2 at. pct Al or Zr by melt spinning in rotating water. The enhancement of the wire-formation tendency by the addition of Al has been clarified to be due to the increase in the stability of the melt jet through the formation of a thin Al/sub 2/O/sub 3/ film on the outer surface. The maximum wire diameter is about 190 to 200 μm for the Ni-Si (or P)-B-Al alloys and increases to about 250 μm for the Ni-Si-B-Al-Cr alloys containing 4 to 6 at. pct Cr. The tensile fracture strength and fracture elongation are 2730 MPa and 2.9 pct for (N/sub 0.75/Si/sub 0.08/B/sub 0.17/)/sub 99/Al/sub 1/ wire and 2170 MPa and 2.4 pct for (Ni/sub 0.78/P/sub 0.12/B/sub 0.1/)/sub 99/Al/sub 1/ wire. These wires exhibit a fatigue limit under dynamic bending strain in air with a relative humidity of 65 pct; this limit is 0.50 pct for a NiSi-B-Al wire, which is higher by 0.15 pct than that of a Fe/sub 75/Si/sub 10/B/sub 15/ amorphous wire. Furthermore, the Ni-base wires do not fracture during a 180-deg bending even for a sample annealed at temperatures just below the crystallization temperature, in sharp contrast to high embrittlement tendency for Fe-base amorphous alloys. Thus, the Ni-based amorphous wires have been shown to be an attractive material similar to Fe- and Co-based amorphous wires because of its high static and dynamic strength, high ductility, high stability to thermal embrittlement, and good corrosion resistance

Long-term decomposition of sugarcane harvest residues in Sao Paulo state, Brazil

International Nuclear Information System (INIS)

Fortes, Caio; Trivelin, Paulo Cesar Ocheuze; Vitti, Andre Cesar

2012-01-01

Crop residues returned to the soil are important to preserve fertility and sustainability. This research addressed the long-term decomposition of sugarcane post-harvest residues (trash) under reduced tillage, therefore field renewal was performed with herbicide followed by subsoiling and ratoons were deprived of interrow scarification. The trial was conducted in the northern Sao Paulo State, Brazil during four consecutive crops (2005–2008) where litter bags containing 15 N-labeled trash were disposed in the field attempting to simulate two distinct situations: the previous crop trash (PCT) or residues incorporated in the field after tillage, and post-harvest trash (PHT) or the remains of plant-cane harvest. Decomposition rates regarding dry matter (DM), carbon (C), root growth, plant nutrients (N, P, K, Ca, Mg and S), lignin (LIG) cellulose (CEL) and hemicellulose (HCEL) contents were assessed for PCT (2005 ndash;2008) and for PHT (2006–2008). There were significant reductions on DM and C:N ratio due to C losses and root growth within the litter bags over time. The DM from PCT and PHT decreased 96% and 73% after four and three crops, respectively, and the higher nutrients release were found for K, Ca and N. The LIG, CEL and HCEL concentrations in PCT decreased 60%, 29%, 70% after four crops and 47%, 35%, 70% from PHT after three crops, respectively. Trash decomposition was driven mainly by residues biochemical composition, root growth within the trash blanket and the climatic conditions during the crop cycles. -- Highlights: ► Degradation of sugarcane previous or post-harvest trash (PCT or PHT) was evaluated. ► Dry matter and C decreased due to microbial and root growth within trash blankets. ► C:N ratio of PCT linearly decreased 23% per year during four consecutive crops. ► Lignin, cellulose and hemicellulose concentration averagely declined 54, 41 and 70%. ► PCT and PHT are long-term sources of C, K, Ca and N to the soil-plant system.

Whole-brain perfusion CT using a toggling table technique to predict final infarct volume in acute ischemic stroke.

Science.gov (United States)

Schrader, I; Wilk, D; Jansen, O; Riedel, C

2013-09-01

To evaluate how accurately final infarct volume in acute ischemic stroke can be predicted with perfusion CT (PCT) using a 64-MDCT unit and the toggling table technique. Retrospective analysis of 89 patients with acute ischemic stroke who underwent CCT, CT angiography (CTA) and PCT using the "toggling table" technique within the first three hours after symptom onset. In patients with successful thrombolytic therapy (n = 48) and in those without effective thrombolytic therapy (n = 41), the infarct volume and the volume of the penumbra on PCT were compared to the infarct size on follow-up images (CT or MRI) performed within 8 days. The feasibility of complete infarct volume prediction by 8 cm cranio-caudal coverage was evaluated. The correlation between the volume of hypoperfusion on PCT defined by cerebral blood volume reduction and final infarct volume was strongest in patients with successful thrombolytic therapy with underestimation of the definite infarct volume by 8.5 ml on average. The CBV map had the greatest prognostic value. In patients without successful thrombolytic therapy, the final infarct volume was overestimated by 12.1 ml compared to the MTT map on PCT. All infarcts were detected completely. There were no false-positive or false-negative results. Using PCT and the "toggling table" technique in acute stroke patients is helpful for the rapid and accurate quantification of the minimal final infarct and is therefore a prognostic parameter which has to be evaluated in further studies to assess its impact on therapeutic decision. ▶ Using PCT and the “toggling table technique” allows accurate quantification of the infarct core and penumbra. ▶ It is possible to record dynamic perfusion parameters quickly and easily of almost the entire supratentorial brain volume on a 64-slice MDCT unit. ▶ The technique allows identification of those patients who could profit from thrombolytic therapy outside the established time intervals. © Georg Thieme Verlag

46 CFR 148.01-7 - Permitted cargoes.

Science.gov (United States)

2010-10-01

... (mixture), containing 6 to 12 pct moisture and no more than 18 pct fat by weight ......do Do. Lead nitrate... cause self heating and the evolution of flammable gas. Aluminum nitrate Oxidizing materials If involved in a fire will greatly intensify the burning of combustible materials. Ammonium nitrate containing...

Serum procalcitonin as an early marker of neonatal sepsis | Ballot ...

African Journals Online (AJOL)

Background. It has recently been suggested that procalcitonin (PCT) is of value in the diagnosis of neonatal sepsis, with varying results. This study was to evaluate the role of PCT as a single early marker of neonatal sepsis. Setting. Neonatal Unit, Johannesburg Hospital, and Microbiology Laboratory, National Health ...

Usefulness of analytical parameters in the management of paediatric patients with suspicion of acute pyelonephritis. Is procalcitonin reliable?

Science.gov (United States)

Bañuelos-Andrío, L; Espino-Hernández, M; Ruperez-Lucas, M; Villar-Del Campo, M C; Romero-Carrasco, C I; Rodríguez-Caravaca, G

To investigate the usefulness of procalcitonin (PCT) and other analytical parameters (white blood cell count [WBC], C-reactive protein [CRP]) as markers of acute renal damage in children after a first febrile or afebrile urinary tract infection (UTI). A retrospective study was conducted on children with a first episode of UTI admitted between January 2009 to December 2011, and in whom serum PCT, CRP and white blood cell count were measured, as well as assessing the acute renal damage with renal scintigraphy with 99m Tc-DMSA (DMSA) within the first 72h after referral. A descriptive study was performed and ROC curves were plotted, with optimal cut-off points calculated for each parameter. The 101 enrolled patients were divided into two groups according to DMSA scintigraphy results, with 64 patients being classified with acute pyelonephritis (APN), and 37 with UTI. The mean WBC, CRP and PCT values were significantly higher in patients with APN with respect to normal acute DMSA. The area under the ROC curve was 0.862 for PCR, 0.774 for WBC, and 0.731 for PCT. The optimum statistical cut-off value for PCT was 0.285ng/ml (sensitivity 71.4% and specificity 75%). Although the mean levels of fever, WBC, CRP, and PCT were significantly increased in patients with APN than in those who had UTI, the sensitivity and specificity of these analytical parameters are unable to predict the existence of acute renal damage, making the contribution by renal DMSA scintigraphy essential. Copyright © 2016 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

Relative cerebral blood volume as a marker of durable tissue-at-risk viability in hyperacute ischemic stroke.

Science.gov (United States)

Cortijo, Elisa; Calleja, Ana Isabel; García-Bermejo, Pablo; Mulero, Patricia; Pérez-Fernández, Santiago; Reyes, Javier; Muñoz, Ma Fe; Martínez-Galdámez, Mario; Arenillas, Juan Francisco

2014-01-01

Selection of best responders to reperfusion therapies could be aided by predicting the duration of tissue-at-risk viability, which may be dependant on collateral circulation status. We aimed to identify the best predictor of good collateral circulation among perfusion computed tomography (PCT) parameters in middle cerebral artery (MCA) ischemic stroke and to analyze how early MCA response to intravenous thrombolysis and PCT-derived markers of good collaterals interact to determine stroke outcome. We prospectively studied patients with acute MCA ischemic stroke treated with intravenous thrombolysis who underwent PCT before treatment showing a target mismatch profile. Collateral status was assessed using a PCT source image-based score. PCT maps were quantitatively analyzed. Cerebral blood volume (CBV), cerebral blood flow, and Tmax were calculated within the hypoperfused volume and in the equivalent region of unaffected hemisphere. Occluded MCAs were monitored by transcranial Duplex to assess early recanalization. Main outcome variables were brain hypodensity volume and modified Rankin scale score at day 90. One hundred patients with MCA ischemic stroke imaged by PCT received intravenous thrombolysis, and 68 met all inclusion criteria. A relative CBV (rCBV) >0.93 emerged as the only predictor of good collaterals (odds ratio, 12.6; 95% confidence interval, 2.9-55.9; P=0.001). Early MCA recanalization was associated with better long-term outcome and lower infarct volume in patients with rCBV<0.93, but not in patients with high rCBV. None of the patients with rCBV<0.93 achieved good outcome in absence of early recanalization. High rCBV was the strongest marker of good collaterals and may characterize durable tissue-at-risk viability in hyperacute MCA ischemic stroke.

[Clinical data that are essential for the primary care clinical records: an experience of evaluation and improvement].

Science.gov (United States)

López-Picazo Ferrer, J J; Agulló Roca, F; Villaescusa Pedemonte, M; Cerezo Corbalán, J M

2002-06-30

To evaluate and improve the presence of essential clinical data in the clinical records of a primary care management area (PCMA) by means of an intervention programme. Intervention study without a control, using evaluation and improvement-of-quality methods. We chose 4 criteria from the minimum technical standards: personal history (PH), family background (FB), allergies to medicines (AM) and list of problems (LP). We evaluated overall compliance and compliance per primary care team (PCT) through batch quality acceptance of samples (LQAS), designed an intervention to improve the situation, and then re-evaluated. PCMA of Murcia (45 PCTs). Participants. 42 PCTs (3 were excluded because they had poor coverage in their records). These lasted 12 months (October 1999-October 2000) and involved the following: graphic report per PCT; session with the PCT; discussion on results and strategies in the Area Management Council; and inclusion of an explicit objective, with incentives, in the management contracts. Significant improvement of the four criteria of the PCMA (improvements: FB, 48.1%; PH, 51.1%; AM, 55.4%; LP, 50.9%). LQAS analysis: we rejected 24 batches (14.3%) at the 1st evaluation and 15 (9.0%) at the second, with FB being the criterion most rejected in both instances. Defects appeared in 14 PCT (33.3%; 3 PCT accounted for 41.7%) at the 1st evaluation, and 7 PCT at the re-evaluation (16.7%; 2 reaching 46.7%). The presence of essential clinical data in clinical records has improved. LQAS proved to be a rapid and simple method for evaluating, improving and monitoring quality in primary care.

Procalcitonin as a diagnostic biomarker for septic shock and bloodstream infection in burn patients from the Formosa Fun Coast dust explosion.

Science.gov (United States)

Wu, Rui-Xin; Chiu, Chih-Chien; Lin, Tzu-Chao; Yang, Ya-Sung; Lee, Yi; Lin, Jung-Chung; Chang, Feng-Yee

2017-12-01

Infection is the most common cause of death following burn injury. The study was conducted to compare the diagnostic value of serum procalcitonin (PCT) with the other current benchmarks as early predictors of septic shock and bloodstream infection in burn patients. We included 24 patients admitted to the Burn Unit of a medical center from June 2015 to December 2015 from the Formosa Fun Coast dust explosion. We categorized all patients at initial admission into either sepsis or septic shock groups. Laboratory tests including the worst PCT and C-reactive protein (CRP) levels, platelet (PLT), and white blood cell (WBC) count were performed at <48 h after admission. Patients were also classified in two groups with subsequent bacteremia and non-bacteremia groups during hospitalization. Significantly higher PCT levels were observed among participants with septic shock compared to those with sepsis (47.19 vs. 1.18 ng/mL, respectively; p < 0.001). Patients with bacteremia had significantly elevated PCT levels compared to patients without bacteremia (29.54 versus 1.81 ng/mL, respectively, p < 0.05). No significant differences were found in CRP levels, PLT, and WBC count between the two groups. PCT levels showed reasonable discriminative power (cut-off: 5.12 ng/mL; p = 0.01) in predicting of bloodstream infection in burn patients and the area under receiver operating curves was 0.92. PCT levels can be helpful in determining the septic shock and bloodstream infection in burn patients but CRP levels, PLT, and WBC count were of little diagnostic value. Copyright © 2017. Published by Elsevier B.V.

Procalcitonin Levels in Gram-Positive, Gram-Negative, and Fungal Bloodstream Infections

Directory of Open Access Journals (Sweden)

Christian Leli

2015-01-01

Full Text Available Procalcitonin (PCT can discriminate bacterial from viral systemic infections and true bacteremia from contaminated blood cultures. The aim of this study was to evaluate PCT diagnostic accuracy in discriminating Gram-positive, Gram-negative, and fungal bloodstream infections. A total of 1,949 samples from patients with suspected bloodstream infections were included in the study. Median PCT value in Gram-negative (13.8 ng/mL, interquartile range (IQR 3.4–44.1 bacteremias was significantly higher than in Gram-positive (2.1 ng/mL, IQR 0.6–7.6 or fungal (0.5 ng/mL, IQR 0.4–1 infections (P<0.0001. Receiver operating characteristic analysis showed an area under the curve (AUC for PCT of 0.765 (95% CI 0.725–0.805, P<0.0001 in discriminating Gram-negatives from Gram-positives at the best cut-off value of 10.8 ng/mL and an AUC of 0.944 (95% CI 0.919–0.969, P<0.0001 in discriminating Gram-negatives from fungi at the best cut-off of 1.6 ng/mL. Additional results showed a significant difference in median PCT values between Enterobacteriaceae and nonfermentative Gram-negative bacteria (17.1 ng/mL, IQR 5.9–48.5 versus 3.5 ng/mL, IQR 0.8–21.5; P<0.0001. This study suggests that PCT may be of value to distinguish Gram-negative from Gram-positive and fungal bloodstream infections. Nevertheless, its utility to predict different microorganisms needs to be assessed in further studies.

Open source deformable image registration system for treatment planning and recurrence CT scans. Validation in the head and neck region

International Nuclear Information System (INIS)

Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Roenn; Bertelsen, Anders; Johansen, Joergen; Eriksen, Jesper Grau; Grau, Cai

2016-01-01

Clinical application of deformable registration (DIR) of medical images remains limited due to sparse validation of DIR methods in specific situations, e. g. in case of cancer recurrences. In this study the accuracy of DIR for registration of planning CT (pCT) and recurrence CT (rCT) images of head and neck squamous cell carcinoma (HNSCC) patients was evaluated. Twenty patients treated with definitive IMRT for HNSCC in 2010-2012 were included. For each patient, a pCT and an rCT scan were used. Median interval between the scans was 8.5 months. One observer manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. pCT and rCT images were deformably registered using the open source software elastix. Mean surface distance (MSD) and Dice similarity coefficient (DSC) between contours were used for validation of DIR. A measure for delineation uncertainty was estimated by assessing MSD from the re-delineations of the same ROI on pCT. DIR and manual contouring uncertainties were correlated with tissue volume and rigidity. MSD varied 1-3 mm for different ROIs for DIR and 1-1.5 mm for re-delineated ROIs performed on pCT. DSC for DIR varied between 0.58 and 0.79 for soft tissues and was 0.79 or higher for bony structures, and correlated with the volumes of ROIs (r = 0.5, p < 0.001) and tissue rigidity (r = 0.54, p < 0.001). DIR using elastix in HNSCC on planning and recurrence CT scans is feasible; an uncertainty of the method is close to the voxel size length of the planning CT images. (orig.) [de

78 FR 52854 - Use of Differential Income Stream as an Application of the Income Method and as a Consideration...

Science.gov (United States)

2013-08-27

... some cases, the present value of an arm's length PCT Payment may be determined as the present value... present value of the differential income stream is consistent with reliable direct evidence of the... appropriate present value of the PCT Payment is $146 million. (ii) Based on the best method analysis described...

Open source deformable image registration system for treatment planning and recurrence CT scans

DEFF Research Database (Denmark)

Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Rønn

2016-01-01

manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. METHODS: pCT and rCT images were deformably registered using the open source software elastix. Mean surface distance (MSD) and Dice similarity coefficient (DSC) between contours were used for validation of DIR...

降钙素原、C 反应蛋白、前清蛋白及白细胞计数在儿童手足口病诊断中的应用价值%Application value of procalcitonin,C-reactive protein,prealbumi and white blood cell in children with hand-foot-and-mouth disease

Institute of Scientific and Technical Information of China (English)

叶贵诚; 彭建明; 官燕飞; 袁斌

2016-01-01

Objective To investigate the application value of procalcitonin (PCT ) ,C-reactive protein (CRP) ,prealbumi (PA ) and white blood cell count (WBC))in children with hand-foot-and-mouth disease (HFMD) .Methods A total of 209 children with HFMD were classified into ordinary group (171 patients) and severe group (38 patients) according to the condition of disease ,an-other 30 healthy children were selected as the control group .The levels of PCT ,CRP ,PA and WBC in the three groups were meas-ured and compared .Results The levels of PCT ,CRP ,PA and WBC of ordinary group were 0 .16(0 .08 - 0 .34)μg/L ,11 .7(5 .0 -19 .0)mg/L ,(142 .6 ± 38 .4)mg /L and (11 .3 ± 4 .6) × 129 /L respectively ,and those of severe group were 0 .26(0 .14 - 0 .92)μg /L , 18 .4(5 .3 - 41 .4) mg /L ,(125 .5 ± 32 .9)mg/L and (13 .0 ± 5 .6) × 129 /L respectively .The PCT ,CRP ,PA and WBC in ordinary group and severe group were significantly different with those in the control group (P < 0 .05) .The PCT ,CRP and PA in severe group had statistical differences compared with those in the ordinary group (P< 0 .05) .Conclusion PCT ,CRP ,PA and WBC could be used as reference indexes of inflammation in HFMD ,and could be used in the diagnosis of HFMD in children ,PCT and PA could be used to evaluate the severity of disease .%目的：探讨降钙素原（PCT）、C 反应蛋白（CRP）、前清蛋白（PA ）、白细胞（WBC）计数在儿童手足口病（HFMD）诊断中的应用价值。方法将209例 HFMD 患儿按病情分为普通病例组（171例）及重症病例组（38例），另外选择同期30例健康体检儿童纳入对照组，测定3组儿童 PCT 、CRP 、PA 及 WBC 水平，并进行比较。结果普通病例组的 PCT 、CRP 、PA 、WBC 水平分别为0．16（0．08～0．34）μg ／L 、11．7（5．0～19．0）mg／L 、（142．6±38．4）mg／L 、（11．3±4．6）×129／L ，重症病例组分别为0．26（0．14～0．92）μg／L 、18．4（5．3～41．4

Bridge deck surface temperature monitoring by infrared thermography and inner structure identification using PPT and PCT analysis methods

Science.gov (United States)

Dumoulin, Jean

2013-04-01

One of the objectives of ISTIMES project was to evaluate the potentialities offered by the integration of different electromagnetic techniques able to perform non-invasive diagnostics for surveillance and monitoring of transport infrastructures. Among the EM methods investigated, we focused our research and development efforts on uncooled infrared camera techniques due to their promising potential level of dissemination linked to their relative low cost on the market. On the other hand, works were also carried out to identify well adapted implementation protocols and key limits of Pulse Phase Thermography (PPT) and Principal Component Thermography (PCT) processing methods to analyse thermal image sequence and retrieve information about the inner structure. So the first part of this research works addresses infrared thermography measurement when it is used in quantitative mode (not in laboratory conditions) and not in qualitative mode (vision applied to survey). In such context, it requires to process in real time thermal radiative corrections on raw data acquired to take into account influences of natural environment evolution with time, thanks to additional measurements. But, camera sensor has to be enough smart to apply in real time calibration law and radiometric corrections in a varying atmosphere. So, a complete measurement system was studied and developed [1] with low cost infrared cameras available on the market. In the system developed, infrared camera is coupled with other sensors to feed simplified radiative models running, in real time, on GPU available on small PC. The whole measurement system was implemented on the "Musmeci" bridge located in Potenza (Italy). No traffic interruption was required during the mounting of our measurement system. The infrared camera was fixed on top of a mast at 6 m elevation from the surface of the bridge deck. A small weather station was added on the same mast at 1 m under the camera. A GPS antenna was also fixed at the

Manufacture of a UO2-Based Nuclear Fuel with Improved Thermal Conductivity with the Addition of BeO

Science.gov (United States)

Garcia, Chad B.; Brito, Ryan A.; Ortega, Luis H.; Malone, James P.; McDeavitt, Sean M.

2017-12-01

The low thermal conductivity of oxide nuclear fuels is a performance-limiting parameter. Enhancing this property may provide a contribution toward establishing accident-tolerant fuel forms. In this study, the thermal conductivity of UO2 was increased through the fabrication of ceramic-ceramic composite forms with UO2 containing a continuous BeO matrix. Fuel with a higher thermal conductivity will have reduced thermal gradients and lower centerline temperatures in the fuel pin. Lower operational temperatures will reduce fission gas release and reduce fuel restructuring. Additions of BeO were made to UO2 fuel pellets in 2.5, 5, 7.5, and 10 vol pct concentrations with the goals of establishing reliable lab-scale processing procedures, minimizing porosity, and maximizing thermal conductivity. The microstructure was characterized with electron probe microanalysis, and the thermal properties were assessed by light flash analysis and differential scanning calorimetry. Reliable, high-density samples were prepared using compaction pressure between 200 and 225 MPa and sintering times between 4 and 6 hours. It was found that the thermal conductivity of UO2 improved approximately 10 pct for each 1 vol pct BeO added over the measured temperature range 298.15 K to 523.15 K (25 °C to 250 °C) with the maximum observed improvement being ˜ 100 pct, or doubled, at 10 vol pct BeO.

Paraequilibrium Carburization of Duplex and Ferritic Stainless Steels

Science.gov (United States)

Michal, G. M.; Gu, X.; Jennings, W. D.; Kahn, H.; Ernst, F.; Heuer, A. H.

2009-08-01

AISI 301 and E-BRITE stainless steels were subjected to low-temperature (743 K) carburization experiments using a commercial technology developed for carburization of 316 austenitic stainless steels. The AISI 301 steel contained ~40 vol pct ferrite before carburization but had a fully austenitic hardened case, ~20- μm thick, and a surface carbon concentration of ~8 at. pct after treatment; this “colossal” paraequilibrium carbon supersaturation caused an increase in lattice parameter of ~3 pct. The E-BRITE also developed a hardened case, 12- to 18- μm thick, but underwent a more modest (~0.3 pct) increase in lattice parameter; the surface carbon concentration was ~10 at. pct. While the hardened case on the AISI 301 stainless steel appeared to be single-phase austenite, evidence for carbide formation was apparent in X-ray diffractometer (XRD) scans of the E-BRITE. Paraequilibrium phase diagrams were calculated for both AISI 301 and E-BRITE stainless steels using a CALPHAD compound energy-based interstitial solid solution model. In the low-temperature regime of interest, and based upon measured paraequilibrium carbon solubilities, more negative Cr-carbon interaction parameters for austenite than those in the current CALPHAD data base may be appropriate. A sensitivity analysis involving Cr-carbon interaction parameters for ferrite found a strong dependence of carbon solubility on relatively small changes in the magnitude of these parameters.

Efficacy of Tectonic Corneal Patch Graft for Progressive Peripheral Corneal Thinning

Directory of Open Access Journals (Sweden)

Cafer Tanrıverdio

2014-12-01

Full Text Available Objectives: To report the results of tectonic corneal patch graft (TCPG in patients with progressive peripheral corneal thinning (PCT. Materials and Methods: In this study, we included 8 patients who underwent TCPG for PCT or perforated corneal ulceration at Ankara Training and Research Hospital. Results: We performed TCPG in 7 patients for PCT and in 1 patient for perforated corneal ulceration. Mean age was 57.2±16.7 (38- 82 years. Postoperative follow-up time ranged from 6 to 24 months (mean 13.9±6.7. Possible etiologies leading to progressive PCT were trachoma, infectious corneal ulcer, and rheumatoid arthritis-severe dry eye in 2 patients each. Other 2 patients had a progressive PCT following ocular surgery. One of the patients with infectious corneal ulcer also had a trauma caused by a scissor. Amnion membrane transplantation was performed in 3 patients prior to TCPG. While the anatomic success was achieved in all 8 patients, best-corrected visual acuity (BCVA was 0.1 or better in 4 patients (50%. Postoperative BCVA was better than preoperative BCVA in 6 patients (75%. Local peripheral anterior synechiae developed in two eyes. Conclusion: TCPG is a useful therapeutic option in selected cases of corneal thinning and perforations because it effectively restores the integrity of the globe and allows acceptable visual results. (Turk J Ophthalmol 2014; 44: 440-4

Large Break LOCA Analysis with New downcomer Nodalizaion and Multi-Dimensional Model and Effect of Cross flow option in MARS code

Energy Technology Data Exchange (ETDEWEB)

Jang, Hyung-wook; Lee, Sang-yong; Oh, Seung-jong; Kim, Woong-bae [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2016-10-15

The phenomena of LOCA have been investigated for long time. The most extensive research project for LOCA was the 2D/3D program experiments. The results of the 2D/3D experiments show flow conditions in the downcomer during end-of-blowdown were highly multi-dimensional at full-scale. In this paper, the authors modified the nodalization of MARS code LBLOCA input deck and performed LBLOCA analysis with new input deck. An LBLOCA analysis for APR1400 with new downcomer input deck was conducted using KREM with MARS-KS 1.4 Version code. Analysis was processed under LBCOCA of 100% break size of cold leg case. The authors developed input deck with new downcomer nodalizaion and Multi-Dimensional downcomer model, then implemented LOCA analysis with new input decks and compared with existing analysis results. PCT from new input and multi-dimensional input deck shows similar PCT trend from original input deck. There occurred more rapid drop of PCT from new and multidimensional input deck than original input deck. PCT from new and multidimensional input deck are satisfied with PCT design limit. It can be concluded that there occurs no acceptance criteria issue even though new and multidimensional input deck are applied to LBLOCA analysis. In future study, comparative analysis with experiment results will be implemented.

Diagnostic accuracy of presepsin (sCD14-ST) as a biomarker of infection and sepsis in the emergency department.

Science.gov (United States)

de Guadiana Romualdo, Luis García; Torrella, Patricia Esteban; Acebes, Sergio Rebollo; Otón, María Dolores Albaladejo; Sánchez, Roberto Jiménez; Holgado, Ana Hernando; Santos, Enrique Jiménez; Freire, Alejandro Ortín

2017-01-01

Presepsin is a promising biomarker for the diagnosis and prognosis of sepsis. However, results reported about its value to diagnose sepsis in an emergency department (ED) are controversial, probably due to differences in the design of the studies. We have evaluated the diagnostic accuracy of presepsin for infection and sepsis, compared with procalcitonin (PCT) and C-reactive protein (CRP), in patients presenting to the emergency department (ED) with suspected infection. 223 patients with suspected infection were enrolled for the study. Blood samples were collected on admission for measurement of biomarkers. Definitive diagnosis was obtained afterwards by analysis of digital medical records. Receiver operating characteristic (ROC) curve analysis was conducted to determine the diagnostic accuracy. Infection was confirmed in 200 patients, including 130 with non-complicated infection and 70 with sepsis. Median CRP, PCT and presepsin levels were significantly higher in patients with infection and sepsis. PCT was the biomarker with the highest performance for infection (ROC AUC: 0.910); for sepsis, PCT (ROC AUC: 0.815) and presepsin (ROC AUC: 0.775) shown a similar performance. Although presepsin is a valuable biomarker for diagnosis of infection and sepsis, its diagnostic accuracy in our study does not improve that of PCT. Its introduction in clinical practice is not justified. Copyright © 2016 Elsevier B.V. All rights reserved.

Fostering clinical engagement and medical leadership and aligning cultural values: an evaluation of a general practice specialty trainee integrated training placement in a primary care trust.

Science.gov (United States)

Ruston, Annmarie; Tavabie, Abdol

2010-01-01

To report on the extent to which a general practice specialty trainee integrated training placement (ITP) developed the leadership skills and knowledge of general practice specialty trainees (GPSTRs) and on the potential of the ITP to improve clinical engagement. A case study method was used in a Kent primary care trust (PCT). Sources of data included face-to-face and telephone interviews (three GPSTRs, three PCT clinical supervisors, three general practitioner (GP) clinical supervisors and three Deanery/PCT managers), reflective diaries, documentary sources and observation. Interview data were transcribed and analysed using the constant comparative method. All respondents were positive about the value and success of the ITP in developing the leadership skills of the GPSTRs covering three dimensions: leadership of self, leadership of teams and leadership of organisations within systems. The ITP had enabled GP trainees to understand the context for change, to develop skills to set the direction for change and to collect and apply evidence to decision making. The ITP was described as an effective means of breaking down cultural barriers between general practice and the PCT and as having the potential for improving clinical engagement. The ITP provided a model to enable the effective exchange of knowledge and understanding of differing cultures between GPSTRs, general practice and the PCT. It provided a sound basis for effective, dispersed clinical engagement and leadership.

Person-Centered Therapy: A Philosophy to Support Early Childhood Education

Science.gov (United States)

Boyer, Wanda

2016-01-01

Person-centered therapy (PCT) comes from the experiential and relationship-oriented therapy tradition. It is considered to be a third force in therapeutic engagement, along with the psychoanalytic and behavioral approaches. PCT is based on faith in and empowerment of human beings to be joyful, creative, self-fulfilled and willing and able to…

Sensitivity Study of the Peak Cladding Temperature for the Pipe Break Accidents of the 3-Pin Fuel Test Loop

International Nuclear Information System (INIS)

Park, S. K.; Chi, D. Y.; Sim, B. S.; Park, K. N.; Ahn, S. H.; Lee, J. M.; Lee, C. Y.; Kim, H. R.

2005-12-01

The effect of the thermal hydraulic operation parameters, the stroke times of safety-related valves, the node number of test fuel for MARS modeling, and the axial power distribution on the peak cladding temperature (PCT) has been investigated for the loss of coolant accident of the 3-pin fuel test loop. The thermal hydraulic operation parameters investigated are the thermal power of the fuel test loop and the flow rate, temperature, and pressure of the main cooling water. The effect of the thermal power and the coolant temperature on the peak cladding temperature is dominant as compared with that of the coolant flow rate and pressure. The maximum PCT increases up to about 34.3K for the room 1 LOCA when the thermal power increase by 5% of the normal operation power and decreases up to about 38.9K for the room 1 LOCA when the coolant temperature decrease by 2% of the normal operation temperature. The effect of the stroke time of the loop isolation valves on the PCT is also dominant. However the effect of the stroke time of the safety injection valves and depressurization vent valves are negligible. Especially the maximum PCT increases up to 25.7K with the increase of the design stroke time of the cold leg loop isolation valve by 13% and decreases up to 25.1K with the decrease of the design stroke time by 13%. The maximum PCT increases by 3.3K as the number of nodes increases from 7 to 14 for the MARS model of test fuel. Three different axial power distributions are also investigated. The maximum PCT occurs for the room 1 LOCA in case the peak power is shifted to the downstream by 20cm

Procalcitonin as a diagnostic biomarker for septic shock and bloodstream infection in burn patients from the Formosa Fun Coast dust explosion

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Rui-Xin Wu

2017-12-01

Full Text Available Background/Purpose: Infection is the most common cause of death following burn injury. The study was conducted to compare the diagnostic value of serum procalcitonin (PCT with the other current benchmarks as early predictors of septic shock and bloodstream infection in burn patients. Methods: We included 24 patients admitted to the Burn Unit of a medical center from June 2015 to December 2015 from the Formosa Fun Coast dust explosion. We categorized all patients at initial admission into either sepsis or septic shock groups. Laboratory tests including the worst PCT and C-reactive protein (CRP levels, platelet (PLT, and white blood cell (WBC count were performed at <48 h after admission. Patients were also classified in two groups with subsequent bacteremia and non-bacteremia groups during hospitalization. Results: Significantly higher PCT levels were observed among participants with septic shock compared to those with sepsis (47.19 vs. 1.18 ng/mL, respectively; p < 0.001. Patients with bacteremia had significantly elevated PCT levels compared to patients without bacteremia (29.54 versus 1.81 ng/mL, respectively, p < 0.05. No significant differences were found in CRP levels, PLT, and WBC count between the two groups. PCT levels showed reasonable discriminative power (cut-off: 5.12 ng/mL; p = 0.01 in predicting of bloodstream infection in burn patients and the area under receiver operating curves was 0.92. Conclusions: PCT levels can be helpful in determining the septic shock and bloodstream infection in burn patients but CRP levels, PLT, and WBC count were of little diagnostic value. Keywords: Procalcitonin, Septic shock, Bloodstream infection, Burn patient, Formosa fun coast dust explosion

The template-assisted electrodeposition of platinum nanowires for catalytic applications

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Soha Mohajeri

2018-05-01

Full Text Available Template-assisted electrodeposition technique was applied to synthesize platinum nanowires (Pt NWs on polycarbonate templates (PCT with pore diameters of 15, 50, and 100 nm for catalytic applications. Influences of sulfuric acid added to the electrolyte, different potential scanning rates and different pore diameters of templates on the electrodeposition process of Pt NWs were investigated by electrochemical techniques, including voltammetry and chronoamperometry methods. It was confirmed that at lower scan rates and in acidic solutions, electrodeposition of platinum on templates with larger pores is controlled by diffusion. The potential range for deposition of Pt NWs was determined and the potentiostatic technique was utilized by applying various potentials of different durations to fabricate the NWs. The morphological characteristics of Pt NWs were examined using the scanning electron microscopy (SEM. It was shown that the growth of Pt NWs on PCT 50 nm followed a pine-tree pattern, while the Pt NWs grew spherically on PCT 100 nm. The uniform and compact shape of Pt NWs was verified by the transmission electron microscopy (TEM. The catalytic activities of the prepared Pt NWs with the same exchanged charge density for hydrogen adsorption/desorption and methanol oxidation reactions were determined by the cyclic voltammetry (CV testing, and the superior electrocatalytic performance was detected for Pt NWs prepared on PCT 50 nm. This enhanced catalytic activity was attributed to the higher surface-to-volume ratio, larger electrochemical active surface area and higher density of exposed active sites accessible on the pine-tree morphology of these Pt NWs compared to the spherical structure of Pt NWs fabricated on PCT 100 nm. This makes Pt NWs prepared on PCT 50 nm to be a promising catalyst for direct methanol fuel cells (DMFCs.

Diagnostic accuracy of soluble urokinase plasminogen activator receptor (suPAR) for prediction of bacteremia in patients with systemic inflammatory response syndrome.

Science.gov (United States)

Hoenigl, Martin; Raggam, Reinhard B; Wagner, Jasmin; Valentin, Thomas; Leitner, Eva; Seeber, Katharina; Zollner-Schwetz, Ines; Krammer, Werner; Prüller, Florian; Grisold, Andrea J; Krause, Robert

2013-02-01

Soluble urokinase plasminogen activator receptor (suPAR) serum concentrations have recently been described to reflect the severity status of systemic inflammation. In this study, the diagnostic accuracy of suPAR, C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6) to predict bacteremia in patients with systemic inflammatory response syndrome (SIRS) was compared. A total of 132 patients with SIRS were included. In 55 patients blood cultures had resulted positive (study group 1, Gram positive bacteria: Staphylococcus aureus and Streptococcus spp., n=15; study group 2, Gram-negative bacteria, n=40) and 77 patients had negative blood culture results (control group, n=77). Simultaneously with blood cultures suPAR, CRP, PCT, IL-6 and white blood count (WBC) were determined. SuPAR values were significantly higher in study group 1 (median 8.11; IQR 5.78-15.53; p=0.006) and study group 2 (median 9.62; IQR 6.52-11.74; p<0.001) when compared with the control group (median 5.65; IQR 4.30-7.83). ROC curve analysis revealed an AUC of 0.726 for suPAR in differentiating SIRS patients with bacteremia from those without. The biomarkers PCT and IL-6 showed comparable results. Regarding combinations of biomarkers multiplying suPAR, PCT and IL-6 was most promising and resulted in an AUC value of 0.804. Initial suPAR serum concentrations were significantly higher (p=0.028) in patients who died within 28 days than in those who survived. No significant difference was seen for PCT, IL-6 and CRP. In conclusion, suPAR, IL-6 and PCT may contribute to predicting bacteremia in SIRS patients. Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Comparison of procalcitonin and high-sensitivity C-reactive protein for the diagnosis of sepsis and septic shock in the oldest old patients.

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Zhang, Hongmin; Wang, Xiaoting; Zhang, Qing; Xia, Ying; Liu, Dawei

2017-08-01

Although the role of serum procalcitonin (PCT) and high-sensitivity C-reactive protein (hs-CRP) in the diagnosis of sepsis and septic shock is well studied, it has not been investigated among oldest old patients. The aim of our study is to determine the role of PCT and hs-CRP in the assessment of sepsis and septic shock in this specific group of patients in the ICU. This is a prospective observational study. Patients >85 years of age admitted to the ICU from May 1st, 2016 to February 1st, 2017 were evaluated. Patients were divided into a sepsis and septic shock group(sepsis/SS) and a non-sepsis group. Serum levels of PCT, hs-CRP and the WBC were measured within 12 h of admission. A total of 70 patients aged 85 years and older were enrolled in this study. Fifty patients were labelled as sepsis/SS and the other 20 were labelled non-sepsis. A ROC analysis showed that the area under the curves (AUC) of hs-CRP and PCT for the discrimination of sepsis/SS patients were 0.825 (95% confidence interval[CI]: 0.73-0.92; P sepsis/SS group, 27 patients had sepsis, while the other 23 patients had septic shock. The ROC analysis showed that the AUCs of hs-CRP and PCT for the discrimination of septic shock patients from sepsis patients were 0.751 (95% CI: 0.62-0.88; P = 0.002) and 0.719 (95% CI:0.57-0.86; p = 0.007), respectively. For the oldest old patients, hs-CRP is not inferior to PCT in the diagnosis of sepsis and septic shock.

37 CFR 1.437 - The drawings.

Science.gov (United States)

2010-07-01

... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false The drawings. 1.437 Section 1... Application § 1.437 The drawings. (a) Drawings are required when they are necessary for the understanding of the invention (PCT Art. 7). (b) The physical requirements for drawings are set forth in PCT Rule 11...

78 FR 78731 - Indoxacarb; Pesticide Tolerances

Science.gov (United States)

2013-12-27

...)phenyl]amino]carbonyl]indeno[1,2- e][1,3,4][oxadiazine-4a(3H)-carboxylate, in or on bean, dry, seed at 0... (PCT) data, and 100 PCT estimates were assumed for the remaining uses. Available processing data for...), and other commodities where translation was applicable. DEEM-FCID TM (ver. 7.81) default processing...

Perioperative chemotherapy vs. neoadjuvant chemoradiation in gastroesophageal junction adenocarcinoma. A population-based evaluation of the Munich Cancer Registry

Energy Technology Data Exchange (ETDEWEB)

Muench, Stefan [Technical University Munich, Department of Radiation Oncology, Klinikum rechts der Isar, Munich (Germany); Habermehl, Daniel; Combs, Stephanie E. [Technical University Munich, Department of Radiation Oncology, Klinikum rechts der Isar, Munich (Germany); Helmholtz Zentrum Muenchen, Institute of Innovative Radiotherapy (iRT), Oberschleissheim (Germany); Agha, Ayman [Staedtisches Klinikum Muenchen, Department of Surgery, Klinikum Bogenhausen, Munich (Germany); Belka, Claus [Ludwig-Maximilians-University (LMU), Department of Radiation Oncology, Klinikum Grosshadern, Munich (Germany); Eckel, Renate; Schubert-Fritschle, Gabriele; Engel, Jutta [Munich Cancer Registry (MCR), Munich Tumour Centre (TZM), Department of Medical Informatics, Biometry and Epidemiology, Klinikum Grosshadern, Ludwig Maximilians University, Munich (Germany); Friess, Helmut [Technische Universitaet Muenchen, Department of Surgery, Klinikum rechts der Isar, Munich (Germany); Gerbes, Alexander [Ludwig Maximilians University (LMU), Department of Gastroenterology and Endocrinology, Klinikum Grosshadern, Munich (Germany); Nuessler, Natascha C. [Staedtisches Klinikum Muenchen, Department of Surgery, Klinikum Neuperlach, Munich (Germany); Schepp, Wolfgang [Staedtisches Klinikum Muenchen, Department of Gastroenterology, Klinikum Bogenhausen, Munich (Germany); Schmid, Roland M. [Technische Universitaet Muenchen, Department of Internal Medicine II, Klinikum rechts der Isar, Munich (Germany); Schmitt, Wolfgang [Staedtisches Klinikum Muenchen, Department of Gastroenterology, Klinikum Neuperlach, Munich (Germany); Weber, Bernhard [Klinik Bad Trissl, Department of Internal Medicine, Oberaudorf (Germany); Werner, Jens [Ludwig Maximilians University (LMU), Department of Surgery, Klinikum Grosshadern, Munich (Germany)

2018-02-15

To date, it remains unclear whether locally advanced adenocarcinoma of the gastroesophageal junction (AEG) should be treated with neoadjuvant chemoradiation (nCRT), analogous to esophageal cancer, or with perioperative chemotherapy (pCT), analogous to gastric cancer. The purpose of this study was to analyze the data of the Munich Cancer Registry (MCR) and to compare pCT and nCRT in AEG patients. A total of 2,992 AEG patients, treated between 1998 and 2014, were included in the study. Baseline and tumor parameters as well as overall survival (OS) and tumor recurrence were compared between 56 patients undergoing nCRT and 64 patients undergoing pCT with UICC stage II/III cancer. In addition, uni- and multivariate analyses using Cox regression models were performed to evaluate the effect of tumor characteristics and treatment regimens on OS. In patients with UICC stage II/III AEG treated with either nCRT or pCT, no significant differences were seen for baseline and tumor characteristics. While there was a significantly higher cumulative incidence of locoregional treatment failure after pCT (32.8%; 95% CI: 18.0-48.4%) compared with nCRT (7.4%; 95% CI: 2.3-16.5%; p = 0.007), there was no significant difference for distant treatment failure (52.9%; 95% CI: 35.4-67.7% and 38.4%; 95% CI: 23.7-52.9%; p = 0.347). When analyzing the whole cohort, patients who received pCT were younger (58.3 years vs. 63.0 years; p = 0.016), had a higher chance of complete tumor resection (81% vs. 67%; p = 0.033), more resected lymph nodes (p = 0.036), and fewer lymph node metastases (p = 0.038) compared with patients who received nCRT. Nevertheless, there was still a strong trend toward a higher incidence of local treatment failure after pCT (25.8%; 95% CI: 14.7-38.3% vs. 12.6%; 95% CI: 5.5-22.8%; p = 0.053). Comparable to the results for patients with UICC stage II/III, no difference was seen for the incidence of distant treatment failure. When excluding patients with UICC stage IV cancer, no

Treatment of real paracetamol wastewater by fenton process

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Dalgic Gamze

2017-01-01

Full Text Available The study investigated the pretreatment of real paracetamol (PCT wastewater of a pharmaceutical industry by Fenton process. At the best experimental conditions (COD/H2O2 = 1/1, Fe+2/H2O2 = 1/70, settling method:centrifuging, pH 6 at settling step, 92.7, 92.7, 95.5, 99.1, 99.9 and 99.4% of chemical oxygen demand (COD, total organic carbon (TOC, 5-day biological oxygen demand (BOD5, PCT, para-amino phenol (PAP and aniline were removed, respectively. Changes in the concentrations of these parameters were also investigated for both oxidation and settling steps of Fenton process. It was found that COD and TOC were removed at the settling step (precipitation whereas PCT, PAP and aniline were removed at the oxidation step. Mass balance calculations were also studied to show the mass distributions of COD in different phases (gas + foam, effluent and sludge. Fenton process was found as an effective method for the pretreatment of real PCT wastewater for discharging in a determined collective treatment plant.

The effect of trace additions of Zn on the precipitation behavior of alloy 8090 during artificial aging

Science.gov (United States)

Kilmer, R. J.; Stoner, G. E.

1991-01-01

The effect(s) of trace additions of Zn to the artificial aging behavior of alloy 8090 (Al-Li-Cu-Mg-Zr) was investigated in the approximate composition range 0-1 wt-pct Zn. Trace Zn additions were found to delay aging and under equivalent aging treatments (100 hrs at 160 C) the alloy without Zn and the 1.07 wt-pct Zn alloy developed delta-prime-free zones along subgrain boundaries, while the alloys of 0.21 and 0.58 wt-pct Zn did not. DSC analysis indicated that Zn was being incorporated into the delta-prime, shifting it's exotherm to higher temperatures, while having little if any effect on its associated endotherm making it unlikely that it is an artifact of a solvus shift. In the 8090 + 1.07 wt-pct Zn alloy, coarse precipitates were found to reside on subgrain boundaries and EDS indicated that they were rich in Cu and Zn. It was also noted that in the Zn containing 8090 varients, the S prime precipitates were more coarse in size than the baseline 8090.

Role of the RS1 sequence of the cholera vibrio in amplification of the segment of plasmid DNA carrying the gene of resistance to tetracycline and the genes of cholera toxin

International Nuclear Information System (INIS)

Fil'kova, S.L.; Il'ina, T.S.; Gintsburg, A.L.; Yanishevskii, N.V.; Smirnov, G.B.

1988-01-01

The hybrid plasmid pCO107, representing cointegrate 14(2)-5(2) of two plasmids, an F-derivative (pOX38) and a PBR322-derivative (pCT105) with an RS1 sequence of the cholera vibrio cloned in its makeup, contains two copes of RS1 at the sites of union of the two plasmids. Using a tetracycline resistance marker (Tc R ) of the plasmid pCT105, clones were isolated which have an elevated level of resistance to tetracycline (an increase of from 4- to 30-fold). Using restriction analysis and the Southern blot method of hybridization it was shown that the increase in the level of resistance of tetracycline is associated with the amplification of pCT105 portion of the cointegrate, and that the process of amplification is governed by the presence of direct repeats of the RS1 sequence at its ends. The increase in the number of copies of the pCT105 segment, which contains in its composition the genes of cholera toxin (vct), is accompanied by an increase in toxin production

Preparing rare earth-silicon-iron-aluminum alloys

International Nuclear Information System (INIS)

Marchant, J.D.; Morrice, E.; Herve, B.P.; Wong, M.M.

1980-01-01

As part of its mission to assure the maximum recovery and use of the Nation's mineral resources, the Bureau of Mines, investigated an improved procedure for producing rare earth-silicon alloys. For example, a charge consisting of 681 grams of mixed rare-earth oxides, 309 grams of ferrosilicon (75 wt-pct Si), and 182 grams of aluminum metal along with a flux consisting of 681 grams of CaO and 45 grams of MgO was reacted at 1500 0 C in an induction furnace. Good slag-metal separation was achieved. The alloy product contained, in weight-percent, 53 RE, 28 Si, 11 Fe, and 4 Al with a rare earth recovery of 80 pct. In current industrial practice rare earth recoveries are usually about 60 pct in alloy products that contain approximately 30 wt-pct each of rare earths and silicon. Metallurgical evaluations showed the alloys prepared in this investigation to be as effective in controlling the detrimental effect of sulfur in steel and cast iron as the commercial rare earth-silicon-iron alloys presently used in the steel industry

The Solubility of Aluminum in Cryolite-Based Electrolyte-Containing KF

Science.gov (United States)

Zhang, Yu; Yu, Jiangyu; Gao, Bingliang; Liu, Yibai; Hu, Xianwei; Shi, Zhongning; Wang, Zhaowen

2016-04-01

The solubility of aluminum in NaF-AlF3-CaF2-KF-A12O3 electrolyte system at 1253 K (980 °C) has been measured by the analysis of quenched samples saturated with aluminum. The content of the dissolved metal in the quenched melt was determined by collecting the volume of hydrogen gas when a finely crushed sample is treated with HCl. Addition of 0 to 5 pct KF has no obvious effect on the solubility of aluminum in cryolite-based melts with molar ratio of NaF/AlF3 (cryolite ratio) ranging from 2.2 to 3.0. The solubility of aluminum increases from 0.015 to 0.026 wt pct with cryolite ratio increases from 2.2 to 4.0 in the NaF-AlF3-5 wt pct CaF2-3 wt pct A12O3 electrolyte at 1253 K (980 °C). Aluminum solubility was affected by both chemical replacement reaction of Al + 3NaF = AlF3 + 3Na and physical dissolution.

The Study of Two Psychotherapy Approaches (Rogers Self Theory and Ellis Rational Theory) in Improvement of Bowen Self-differentiation and Intimacy.

Science.gov (United States)

Yousefi, Naser; Kiani, Mohammad Ali

2014-01-01

To compare the effectiveness of rational, behavioral and emotive therapy (REBT) and person-centered therapy (PCT) on self-differentiation and intimacy among divorce clients. In quasi-experimental study, 42 divorce clients (both males and females) who presented to the Counsling Center of Sanandaj, Iran were sampled. They were categorized into three groups of PCT, REBT, and control group (each group contained 14 subjects). The recovery indices (dependent variables) employed were the subject of self-differentiation and intimacy, which were measured twice before and after intervention of Differentiation of Self Inventory-2 (DSI-2) and intimacy. The therapy involved 8 one-hour sessions. It was held twice a week and therapeutic effects were traced after 8 months. The results showed that REBT and PCT were effective on self-differentiation scale and intimacy. Also they were influential in recovery self-differentiation scale and intimacy follow up stage. REBT and PCT were effective on self-differentiation and its subscales (Emotional reactivity, "I" position, Emotional cut off and Fusion with other) and general intimacy. None.

Design and Construction of Detector and Data Acquisition Elements for Proton Computed Tomography

International Nuclear Information System (INIS)

Fermi Research Alliance; Northern Illinois University

2015-01-01

Proton computed tomography (pCT) offers an alternative to x-ray imaging with potential for three-dimensional imaging, reduced radiation exposure, and in-situ imaging. Northern Illinois University (NIU) is developing a second-generation proton computed tomography system with a goal of demonstrating the feasibility of three-dimensional imaging within clinically realistic imaging times. The second-generation pCT system is comprised of a tracking system, a calorimeter, data acquisition, a computing farm, and software algorithms. The proton beam encounters the upstream tracking detectors, the patient or phantom, the downstream tracking detectors, and a calorimeter. The schematic layout of the PCT system is shown. The data acquisition sends the proton scattering information to an offline computing farm. Major innovations of the second generation pCT project involve an increased data acquisition rate ( MHz range) and development of three-dimensional imaging algorithms. The Fermilab Particle Physics Division and Northern Illinois Center for Accelerator and Detector Development at Northern Illinois University worked together to design and construct the tracking detectors, calorimeter, readout electronics and detector mounting system.

Produktion og afsætning af nicheprodukter

DEFF Research Database (Denmark)

Jensen, Jonas Baungaard; Hansen, Henning Otte

2016-01-01

. Egnsmærker opnår generelt en merpris på 20-30 pct. Det er dog bemærkelsesværdigt, at landmanden “kun” har omkring 13 pct. af forbrugerkronen på Lammefjords-kartofler. Her er der tale om unikke produkter, hvor det i praksis udelukkende er landmanden og landmandens placering og produktion, som skaber de unikke...

Remedial treatment of lodgepole pine infested with mountain pine beetle: efficacy of three insecticides

Science.gov (United States)

Paul E. Tilden

1985-01-01

Lindane is registered for remedial control of bark beetles; however, forestry uses are controversial and alternative chemicals are needed. Chlorpyrifos (Dursban 4E), carbaryl (Sevimol 4), and fenitrothion (Sumithion 8E) at 1, 2, and 4 pct active ingredient, and lindane at the registered dosage of 0.6 pct were sprayed on lodgepole pine (Pinus contorta...

Diagnostic and prognostic value of presepsin in the management of sepsis in the emergency department: a multicenter prospective study.

Science.gov (United States)

Ulla, Marco; Pizzolato, Elisa; Lucchiari, Manuela; Loiacono, Maria; Soardo, Flavia; Forno, Daniela; Morello, Fulvio; Lupia, Enrico; Moiraghi, Corrado; Mengozzi, Giulio; Battista, Stefania

2013-07-30

Sepsis, severe sepsis and septic shock are common conditions with high mortality. Their early diagnosis in the Emergency Department (ED) is one of the keys to improving survival. Procalcitonin (PCT) has been used as a biomarker in septic patients but has limited specificity and can be elevated in other scenarios of systemic inflammatory response syndrome (SIRS). Soluble CD14 (sCD14) or presepsin is the free fragment of a glycoprotein expressed on monocytes and macrophages. Preliminary reports suggest that levels of presepsin are significantly higher in septic patients than in healthy individuals. The aim of this study is to investigate the diagnostic and prognostic value of presepsin compared to PCT in people presenting at the ED with SIRS and suspected sepsis or septic shock. This study was conducted in two major hospitals in Turin, Italy. One hundred six patients presenting to the EDs with suspected sepsis or septic shock were included, and another eighty-three patients affected by SIRS, but with no clinical evidence of infection, were recruited as controls. Blood samples were collected at first medical evaluation and for some patients after 24 and 72 h. The samples were analyzed using the PATHFAST Presepsin assay for sCD14, and commercial kits were used for other determinations (for example, PCT). Definitive diagnosis and survival rates were obtained afterward by analysis of digital medical records. Elevated concentrations of presepsin at presentation were observed in septic patients compared to control patients. The same trend was observed for mean values of PCT. Higher values of presepsin were observed in septic patients at presentation (time 0). The diagnostic accuracy of PCT was generally higher, and areas under the curve (AUCs) were 0.875 for PCT and 0.701 for presepsin. Mean presepsin values were significantly higher in nonsurvivor septic patients (60-day mortality) than in survivors. No significant correlation was noted between PCT and survival. In our

In honour of N. Yngve Öhrn: surveying proton cancer therapy reactions with Öhrn's electron nuclear dynamics method. Aqueous clusters radiolysis and DNA-base damage by proton collisions

Science.gov (United States)

Mclaurin, Patrick M.; Privett, Austin J.; Stopera, Christopher; Grimes, Thomas V.; Perera, Ajith; Morales, Jorge A.

2015-02-01

Proton cancer therapy (PCT) utilises high-energy H+ projectiles to cure cancer. PCT healing arises from its DNA damage in cancerous cells, which is mostly inflicted by the products from PCT water radiolysis reactions. While clinically established, a complete microscopic understanding of PCT remains elusive. To help in the microscopic elucidation of PCT, Professor Öhrn's simplest-level electron nuclear dynamics (SLEND) method is herein applied to H+ + (H2O)3-4 and H+ + DNA-bases at ELab = 1.0 keV. These are two types of computationally feasible prototypes to study water radiolysis reactions and H+-induced DNA damage, respectively. SLEND is a time-dependent, variational, non-adiabatic and direct-dynamics method that adopts a nuclear classical-mechanics description and an electronic single-determinantal wavefunction. Additionally, our SLEND + effective-core-potential method is herein employed to simulate some computationally demanding PCT reactions. Due to these attributes, SLEND proves appropriate for the simulation of various types of PCT reactions accurately and feasibly. H+ + (H2O)3-4 simulations reveal two main processes: H+ projectile scattering and the simultaneous formation of H and OH fragments; the latter process is quantified through total integrals cross sections. H+ + DNA-base simulations reveal atoms and groups displacements, ring openings and base-to-proton electron transfers as predominant damage processes. The authors warmly dedicate this SLEND investigation in honour of Professor N. Yngve Öhrn on the occasion of his 80th birthday celebration during the 54th Sanibel Symposium in St. Simons' Island, Georgia, on February 16-21, 2014. Associate Professor Jorge A. Morales was a former chemistry PhD student under the mentorship of Professor Öhrn and Dr Ajith Perera took various quantum chemistry courses taught by Professor Öhrn during his chemistry PhD studies. Both Jorge and Ajith look back to those great times of their scientific formation under

Serum Procalcitonin and Peripheral Venous Lactate for Predicting Dengue Shock and/or Organ Failure: A Prospective Observational Study.

Directory of Open Access Journals (Sweden)

Vipa Thanachartwet

2016-08-01

Full Text Available Currently, there are no biomarkers that can predict the incidence of dengue shock and/or organ failure, although the early identification of risk factors is important in determining appropriate management to reduce mortality. Therefore, we sought to determine the factors associated with dengue shock and/or organ failure and to evaluate the prognostic value of serum procalcitonin (PCT and peripheral venous lactate (PVL levels as biomarkers of dengue shock and/or organ failure.A prospective observational study was conducted among adults hospitalized for confirmed viral dengue infection at the Hospital for Tropical Diseases in Bangkok, Thailand between October 2013 and July 2015. Data, including baseline characteristics, clinical parameters, laboratory findings, serum PCT and PVL levels, management, and outcomes, were recorded on pre-defined case report forms. Of 160 patients with dengue, 128 (80.0% patients had dengue without shock or organ failure, whereas 32 (20.0% patients developed dengue with shock and/or organ failure. Using a stepwise multivariate logistic regression analysis, PCT ≥0.7 ng/mL (odds ratio [OR]: 4.80; 95% confidence interval [CI]: 1.60-14.45; p = 0.005 and PVL ≥2.5 mmol/L (OR: 27.99, 95% CI: 8.47-92.53; p <0.001 were independently associated with dengue shock and/or organ failure. A combination of PCT ≥0.7 ng/mL and PVL ≥2.5 mmol/L provided good prognostic value for predicting dengue shock and/or organ failure, with an area under the receiver operating characteristics curve of 0.83 (95% CI: 0.74-0.92, a sensitivity of 81.2% (95% CI: 63.6-92.8%, and a specificity of 84.4% (95% CI: 76.9-90.2%. Dengue shock patients with non-clearance of PCT and PVL expired during hospitalization.PCT ≥0.7 ng/mL and PVL ≥2.5 mmol/L were independently associated with dengue shock and/or organ failure. The combination of PCT and PVL levels could be used as prognostic biomarkers for the prediction of dengue shock and/or organ failure.

A highly stable and sensitive GO-XDA-Mn2O3 electrochemical sensor for simultaneous electrooxidation of paracetamol and ascorbic acid

International Nuclear Information System (INIS)

Ejaz, Ammara; Jeon, Seungwon

2017-01-01

Highlights: •π–π interaction of graphene oxide (GO) with 1,4-xylenediamine (XDA) was studied. •The synergistic effect of the Mn 2 O 3 nanospheres with GO-XDA was electrochemically studied in the detection of Paracetamol (PCT) and ascorbic acid (AA). •The GO-XDA-Mn 2 O 3 accurately detected PCT and AA with LOD of 5.6 × 10 −8 M and 6.0 × 10 −7 M respectively. •The GO-XDA-Mn 2 O 3 selectively detected PCT and AA simultaneously in the presence of DA, 5-HT and Glu with peak separation of 240 mV. -- Abstract: Highly stable electrochemical sensor based on strong π- π interactions between GO and XDA was fabricated for simultaneous as well as for individual detection of paracetamol (PCT) and ascorbic acid (AA). The oxidation potential of PCT and AA was greatly resolved with the decoration of Mn 2 O 3 nanospheres. We believe that, presence of metal oxide on the surface of GO-XDA will offer higher electrochemical performance with its large surface area and fast electron transfer ability. Therefore, a comparative study was executed in the presence and absence of Mn 2 O 3 nanospheres on the surface of GO-XDA. The GO-XDA-Mn 2 O 3 modified electrode showed electrocatalytic oxidation of PCT in a very wide linear range of 1 × 10 −6 –1 × 10 −3 M with limit of detection (LOD) and sensitivity of 5.6 × 10 −8 M, 527.04 μAmM −1 cm −2 respectively and AA with 1 × 10 −5 –8 × 10 −3 M linear range, LOD and sensitivity of 6.0 × 10 −7 M, 655.74 μAmM −1 cm −2 respectively. Furthermore, astonishing stability was found when GO-XDA-Mn 2 O 3 nanocomposite was stored for over a week. The proposed sensor displayed incredible selectivity, sensitivity and excellent recovery results for real samples with appreciable consistency and precision suggesting practical utility of the GO-XDA-Mn 2 O 3 as an effective and reliable electrochemical sensor for simultaneous as well as individual determination of PCT and AA.

Application of fluence field modulation to proton computed tomography for proton therapy imaging.

Science.gov (United States)

Dedes, G; De Angelis, L; Rit, S; Hansen, D; Belka, C; Bashkirov, V; Johnson, R P; Coutrakon, G; Schubert, K E; Schulte, R W; Parodi, K; Landry, G

2017-07-12

This simulation study presents the application of fluence field modulated computed tomography, initially developed for x-ray CT, to proton computed tomography (pCT). By using pencil beam (PB) scanning, fluence modulated pCT (FMpCT) may achieve variable image quality in a pCT image and imaging dose reduction. Three virtual phantoms, a uniform cylinder and two patients, were studied using Monte Carlo simulations of an ideal list-mode pCT scanner. Regions of interest (ROI) were selected for high image quality and only PBs intercepting them preserved full fluence (FF). Image quality was investigated in terms of accuracy (mean) and noise (standard deviation) of the reconstructed proton relative stopping power compared to reference values. Dose calculation accuracy on FMpCT images was evaluated in terms of dose volume histograms (DVH), range difference (RD) for beam-eye-view (BEV) dose profiles and gamma evaluation. Pseudo FMpCT scans were created from broad beam experimental data acquired with a list-mode pCT prototype. FMpCT noise in ROIs was equivalent to FF images and accuracy better than  -1.3%(-0.7%) by using 1% of FF for the cylinder (patients). Integral imaging dose reduction of 37% and 56% was achieved for the two patients for that level of modulation. Corresponding DVHs from proton dose calculation on FMpCT images agreed to those from reference images and 96% of BEV profiles had RD below 2 mm, compared to only 1% for uniform 1% of FF. Gamma pass rates (2%, 2 mm) were 98% for FMpCT while for uniform 1% of FF they were as low as 59%. Applying FMpCT to preliminary experimental data showed that low noise levels and accuracy could be preserved in a ROI, down to 30% modulation. We have shown, using both virtual and experimental pCT scans, that FMpCT is potentially feasible and may allow a means of imaging dose reduction for a pCT scanner operating in PB scanning mode. This may be of particular importance to proton therapy given the low integral dose found

Positron computed tomography. Present and future design alternatives

International Nuclear Information System (INIS)

Phelps, M.E.; Hoffman, E.J.; Sung-Cheng Huang; Kuhl, D.E.

1981-01-01

There are six commercial companies in the United States of America, Canada, Europe and Asia that have or are developing PCT programs. Although positron computed tomography (PCT) system designs are still evolving and all the complex issues of system optimization are still not completely defined, some design concepts have achieved general acceptance. Circumferential designs employing hexagonal, octagonal or circular geometries are preferred since they maximize the tomographic plane efficiency. Bismuth germanate has become the detector of choice because of its high efficiency (intrinsic photopeak and geometric through high packing densities) when the small detectors required for high spatial resolution are used. Caesium fluoride detectors are also being investigated because of their short coincidence time resolution and potential for time of flight measurements. Multiplane systems, consisting of stacked single plane geometries, have been developed to provide higher overall organ efficiency, with some compromise in image quality compared with a single plane system. The most poorly characterized aspect of multiplane systems is the slit and septa shielding design that has a large impact on random and scatter coincidences, count-rate capability, efficiency and uniformity of spatial resolution. Present PCT systems have spatial resolutions in the tomographic plane of about 8 to 17 mm and axial resolution of about 12 to 18 mm. PCT systems that have been or are now being developed are providing the means to demonstrate the unique capability of PCT to provide quantitative measurements of local biochemical and functional processes in man

Evaluation of cumulative effects of MR imaging on pacemaker systems at 1.5 Tesla.

Science.gov (United States)

Naehle, Claas P; Zeijlemaker, Volkert; Thomas, Daniel; Meyer, Carsten; Strach, Katharina; Fimmers, Rolf; Schild, Hans; Sommer, Torsten

2009-12-01

The purpose of this study was to evaluate possible cumulative effects of repeated magnetic resonance imaging (MRI) examinations on pacemaker systems in patients with cardiac pacemakers. The records of pacemaker patients who underwent repetitive MRI examinations in our institution were reviewed to identify patients who underwent two or more MRI examinations at 1.5T of any anatomical region. Using these criteria, a total of 47 patients who underwent a total 171 MRI examinations were identified and included in this study. Institutional Review Board approval for all pacemaker investigations was obtained. Written informed consent was obtained from all patients. Pacemakers were interrogated immediately before and after MR imaging, and after 3 months, including measurement of pacing capture threshold (PCT), lead impedance (LI), and battery voltage (BV). PCT, LI, and BV were analyzed for changes dependant on the number of MRI exams performed. Mean changes over time and changes between first and last pacemaker interrogation of PCT, LI, and BV were calculated. A statistically significant (P < 0.05), but clinically irrelevant trend for decrease in PCT and BV was found. No significant or clinically relevant changes in LI were observed. In this first study, no clinically relevant, cumulative changes in PCT, LI, or BV could be detected in PM patients who underwent two or more MRI examinations. However, a careful benefit/risk evaluation, among other MRI- and pacemaker-related safety precautions, remains mandatory, as clinically relevant alterations to the PM system cannot be excluded by all means.

Reduction kinetics of Wüstite scale on pure iron and steel sheets in Ar and H

NARCIS (Netherlands)

Mao, W.; Sloof, W.G.

2017-01-01

A dense and closed Wüstite scale is formed on pure iron and Mn alloyed steel after oxidation in Ar + 33 vol pct CO₂ + 17 vol pct CO gas mixture. Reducing the Wüstite scale in Ar + H₂ gas mixture forms a dense and uniform iron layer on top of the remaining Wüstite scale,

Comparative Study of Plasma Endotoxin with Procalcitonin Levels in Diagnosis of Bacteremia in Intensive Care Unit Patients

Directory of Open Access Journals (Sweden)

Tao Wang

2016-01-01

Conclusions: Plasma endotoxin was more related to GN than to Gram-positive bacteremia, and that endotoxin level was species dependent, but PCT level remained relatively more stable within the GN bacteria caused bacteremia. Both GN and positive bacteria caused bacteremia in the ICU patients in different regions of China. And PCT is a more valuable biomarker than endotoxin in the diagnosis of bacteremia.

Risbjerg: Historisk stemmeskred med NA

DEFF Research Database (Denmark)

Thomsen, Søren Risbjerg

2007-01-01

ANALYSE: NA flytter 12,3 pct. af stemmerne i majs meningsmålinger - historisk mange vælgere på en måned, skriver professor Risbjerg. Udgivelsesdato: 3. juni 2007......ANALYSE: NA flytter 12,3 pct. af stemmerne i majs meningsmålinger - historisk mange vælgere på en måned, skriver professor Risbjerg. Udgivelsesdato: 3. juni 2007...

Use of Industrial Waste (Al-Dross, Red Mud, Mill Scale) as Fluxing Agents in the Sulfurization of Fe-Ni-Cu-Co Alloy by Carbothermic Reduction of Calcium Sulfate

Science.gov (United States)

Heo, Jung Ho; Jeong, Eui Hyuk; Nam, Chul Woo; Park, Kyung Ho; Park, Joo Hyun

2018-03-01

The use of industrial waste [mill scale (MS), red mud (RM), Al-dross (AD)] as fluxing agents in the sulfurization of Fe-Ni-Cu-Co alloy to matte (Fe-Ni-Cu-Co-S) by carbothermic reduction of CaSO4 was investigated at 1673 K (1400 °C). The sulfurization efficiency (SE) was 76 (± 2) pct at RM or AD single fluxing. However, SE drastically increased to approximately 89 pct at a `5AD + 5MS' combination, which was equivalent to reagent-grade chemical `5Al2O3 + 5Fe2O3' fluxing (SE = 88 pct). The present results can be used to improve the cost-effective recovery of rare metals (Ni and Co) from deep sea manganese nodules.

Influence of molybdenum on the creep properties of nickel-base superalloy single crystals

Science.gov (United States)

Mackay, R. A.; Nathal, M. V.; Pearson, D. D.

1990-01-01

The Mo content of an alloy series based on Ni-6 wt pct Al-6 wt pct Ta was systematically varied from 9.8 to 14.6 wt pct, in order to ascertain the influence of Mo on the creep properties of single crystals. The optimum initial gamma-gamma prime microstructure for raft development and creep strength was established in each alloy before testing. It was found that, as the Mo content increased from 9.8 to 14.0 percent, the magnitude of the lattice mismatch increased; upon reaching 14.6 percent, a degradation of mechanical properties occurred due to the precipitation of a third phase. These results suggest that small refractory metal content and initial gamma-prime variations can profoundly affect mechanical properties.

Studies on the influence of metallurgical variables on the stress corrosion behavior of AISI 304 stainless steel in sodium chloride solution using the fracture mechanics approach

International Nuclear Information System (INIS)

Khatak, H.S.; Gnanamoorthy, J.B.; Rodriguez, P.

1996-01-01

Stress corrosion data on a nuclear grade AISI type 304 stainless steel in a boiling solution of 5M NaCl + 0.15M Na 2 SO 4 + 3 mL/L HCl (bp 381 K) for various metallurgical conditions of the steel are presented in this article. The metallurgical conditions used are solution annealing, sensitization, 10 pct cold work, 20 pct cold work, solution annealing + sensitization, 10 pct cold work + sensitization, and 20 pct cold work + sensitization. The fracture mechanics approach has been used to obtain quantitative data on the stress corrosion crack growth rates. The stress intensity factor, K I , and J integral, J I , have been used as evaluation parameters. The crack growth rates have been measured using compact tension type samples under both increasing and decreasing stress intensity factors. A crack growth rate of 5 x 10 -11 m/s was chosen for the determination of threshold parameters. Results of the optical microscopic and fractographic examinations are presented. Acoustic signals were recorded during crack growth. Data generated from acoustic emissions, activation energy measurements, and fractographic features indicate hydrogen embrittlement as the possible mechanism of cracking

[Accesibility and use of spirometry in primary care centers in Catalonia].

Science.gov (United States)

Llauger, M Antònia; Rosas, Alba; Burgos, Felip; Torrente, Elena; Tresserras, Ricard; Escarrabill, Joan

2014-01-01

Examine the accessibility and use of forced spirometry (FS) in public primary care facilities centers in Catalonia. Cross-sectional study using a survey. Three hundred sixty-six Primary Care Teams (PCT) in Catalonia. Third quarter of 2010. Survey with information on spirometers, training, interpretation and quality control, and the priority that the quality of spirometry had for the team. Indicators FS/100 inhabitants/year, FS/month/PCT; FS/month/10,000 inhabitants. Response rate: 75%. 97.5% of PCT had spirometer and made an average of 2.01 spirometries/100 inhabitants (34.68 spirometry/PCT/month). 83% have trained professionals.>50% centers perform formal training but no information is available on the quality. 70% performed some sort of calibration. Interpretation was made by the family physician in 87.3% of cases. In 68% of cases not performed any quality control of exploration. 2/3 typed data manually into the computerized medical record.>50% recognized a high priority strategies for improving the quality. Despite the accessibility of EF efforts should be made to standardize training, increasing the number of scans test and promote systematic quality control. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Simultaneous spectrophotometric determination of overlapping spectra of paracetamol and caffeine in laboratory prepared mixtures and pharmaceutical preparations using continuous wavelet and derivative transform

Directory of Open Access Journals (Sweden)

Ahmed Ashour

2015-03-01

Full Text Available In the present paper, two spectrophotometric methods were used for the simultaneous analysis of paracetamol (PCT and caffeine (CAF in their laboratory prepared mixtures and pharmaceutical preparations. Simple spectrophotometric analysis of PCT and CAF is not possible due to their complete spectral overlap. The proposed methods are based on the application of continuous wavelet transform (CWT and derivative transform (using Savitsky–Golay filters on the ratio spectra to predict each of CAF and PCT. Several wavelet families were tested. Coif1 and Sym2 were found to give best results under optimum conditions. The transformed signals of ratio spectra were used to plot the calibration curves for both components. The predictability of the built calibrations was validated through their application on several synthetic mixtures of both drugs. The proposed methods were used for the prediction of CAF and PCT in pharmaceutical preparation. The obtained results were statistically compared to a reference HPLC method. No significant differences were found between the obtained results and those from the reference method. Being simple, rapid, cheap and sensitive, the proposed methods are recommended for the routine daily analysis of these two drugs in their mixtures in quality control laboratories.

Peak cladding temperature in a spent fuel storage or transportation cask

International Nuclear Information System (INIS)

Li, J.; Murakami, H.; Liu, Y.; Gomez, P.E.A.; Gudipati, M.; Greiner, M.

2007-01-01

From reactor discharge to eventual disposition, spent nuclear fuel assemblies from a commercial light water reactor are typically exposed to a variety of environments under which the peak cladding temperature (PCT) is an important parameter that can affect the characteristics and behavior of the cladding and, thus, the functions of the spent fuel during storage, transportation, and disposal. Three models have been identified to calculate the peak cladding temperature of spent fuel assemblies in a storage or transportation cask: a coupled effective thermal conductivity and edge conductance model developed by Manteufel and Todreas, an effective thermal conductivity model developed by Bahney and Lotz, and a computational fluid dynamics model. These models were used to estimate the PCT for spent fuel assemblies for light water reactors under helium, nitrogen, and vacuum environments with varying decay heat loads and temperature boundary conditions. The results show that the vacuum environment is more challening than the other gas environments in that the PCT limit is exceeded at a lower boundary temperature for a given decay heat load of the spent fuel assembly. This paper will highlight the PCT calculations, including a comparison of the PCTs obtained by different models.

Influence of Prior Fatigue Cycling on Creep Behavior of Reduced Activation Ferritic-Martensitic Steel

Science.gov (United States)

Sarkar, Aritra; Vijayanand, V. D.; Parameswaran, P.; Shankar, Vani; Sandhya, R.; Laha, K.; Mathew, M. D.; Jayakumar, T.; Rajendra Kumar, E.

2014-06-01

Creep tests were carried out at 823 K (550 °C) and 210 MPa on Reduced Activation Ferritic-Martensitic (RAFM) steel which was subjected to different extents of prior fatigue exposure at 823 K at a strain amplitude of ±0.6 pct to assess the effect of prior fatigue exposure on creep behavior. Extensive cyclic softening that characterized the fatigue damage was found to be immensely deleterious for creep strength of the tempered martensitic steel. Creep rupture life was reduced to 60 pct of that of the virgin steel when the steel was exposed to as low as 1 pct of fatigue life. However, creep life saturated after fatigue exposure of 40 pct. Increase in minimum creep rate and decrease in creep rupture ductility with a saturating trend were observed with prior fatigue exposures. To substantiate these findings, detailed transmission electron microscopy studies were carried out on the steel. With fatigue exposures, extensive recovery of martensitic-lath structure was distinctly observed which supported the cyclic softening behavior that was introduced due to prior fatigue. Consequently, prior fatigue exposures were considered responsible for decrease in creep ductility and associated reduction in the creep rupture strength.

Phase Equilibria of Sn-Co-Cu Ternary System

Science.gov (United States)

Chen, Yu-Kai; Hsu, Chia-Ming; Chen, Sinn-Wen; Chen, Chih-Ming; Huang, Yu-Chih

2012-10-01

Sn-Co-Cu ternary alloys are promising lead-free solders, and isothermal sections of Sn-Co-Cu phase equilibria are fundamentally important for the alloys' development and applications. Sn-Co-Cu ternary alloys were prepared and equilibrated at 523 K, 1073 K, and 1273 K (250 °C, 800 °C, and 1000 °C), and the equilibrium phases were experimentally determined. In addition to the terminal solid solutions and binary intermetallic compounds, a new ternary compound, Sn3Co2Cu8, was found. The solubilities of Cu in the α-CoSn3 and CoSn2 phases at 523 K (250 °C) are 4.2 and 1.6 at. pct, respectively, while the Cu solubility in the α-Co3Sn2 phase is as high as 20.0 at. pct. The Cu solubility increases with temperature and is around 30.0 at. pct in the β-Co3Sn2 at 1073 K (800 °C). The Co solubility in the η-Cu6Sn5 phase is also significant and is 15.5 at. pct at 523 K (250 °C).

Comparison of plasma/serum levels of procalcitonin between infection and febrile disease flare in patients with systemic lupus erythematosus: a meta-analysis.

Science.gov (United States)

Liu, Li-Na; Wang, Peng; Guan, Shi-Yang; Li, Xiao-Mei; Li, Bao-Zhu; Leng, Rui-Xue; Pan, Hai-Feng

2017-12-01

Currently published data regarding the potential role of procalcitonin (PCT) for the discrimination between systemic lupus erythematosus (SLE) flare and infection are contradictory. To derive a more precise evaluation, a meta-analysis was performed. Published literatures from PubMed, Embase, and the Cochrane Library were obtained. The Newcastle-Ottawa Scale was used to assess the study quality. Pooled standard mean difference (SMD) with 95% confidence interval (CI) was calculated by random-effect model analysis. Heterogeneity test was performed by the Q statistic and quantified using I 2 . Eight studies including 205 SLE flare patients and 198 SLE patients with infection were finally incorporated in the meta-analysis after examining title, type, abstracts, and full text. No significant differences in plasma/serum PCT levels were found between SLE patients with flare and SLE patients with infection when all studies were pooled into the meta-analysis (pooled SMD = - 0.45, 95% CI = - 0.96 to 0.06). However, subgroup analysis showed that Asian SLE patients with infection had higher plasma/serum PCT levels when compared with SLE patients with flare (p infection. However, plasma/serum PCT levels are significantly higher in Asian SLE patients with infection.

Dynamic CT perfusion imaging of intra-axial brain tumours: differentiation of high-grade gliomas from primary CNS lymphomas

International Nuclear Information System (INIS)

Schramm, Peter; Xyda, Argyro; Knauth, Michael; Klotz, Ernst; Tronnier, Volker; Hartmann, Marius

2010-01-01

Perfusion computed tomography (PCT) allows to quantitatively assess haemodynamic characteristics of brain tissue. We investigated if different brain tumor types can be distinguished from each other using Patlak analysis of PCT data. PCT data from 43 patients with brain tumours were analysed with a commercial implementation of the Patlak method. Four patients had low-grade glioma (WHO II), 31 patients had glioblastoma (WHO IV) and eight patients had intracerebral lymphoma. Tumour regions of interest (ROIs) were drawn in a morphological image and automatically transferred to maps of cerebral blood flow (CBF), cerebral blood volume (CBV) and permeability (K Trans ). Mean values were calculated, group differences were tested using Wilcoxon and Mann Whitney U-tests. In comparison with normal parenchyma, low-grade gliomas showed no significant difference of perfusion parameters (p > 0.05), whereas high-grade gliomas demonstrated significantly higher values (p Trans , p Trans values compared with unaffected cerebral parenchyma (p = 0.0078) but no elevation of CBV. High-grade gliomas show significant higher CBV values than lymphomas (p = 0.0078). PCT allows to reliably classify gliomas and lymphomas based on quantitative measurements of CBV and K Trans . (orig.)

Effect of oxygen on the strength and ductility of polycrystalline vanadium in the range of 4.2 to 400 K

International Nuclear Information System (INIS)

Carlson, O.N.; Alexander, D.G.; Elssner, G.

1977-01-01

The effect of oxygen on the yield stress and ductility of polycrystalline vanadium was investigated for concentrations of 0.004 to 1.25 at pct oxygen over the temperature range of 4.2 to 400 K. The dependence of the resolved shear stress on temperature and composition was tested against the different interstitial solute strengthening theories. A parabolic dependence of tau on concentration was found to hold in the low solute concentration range and a linear dependence was observed at high oxygen concentrations. A statistical model proposed by Labusch gives a good description of the concentration dependence of the shear stress for the entire temperature-composition range investigated. This correlation suggests that a spectrum of defects may be contributing to the strengthening of vanadium-oxygen alloys. The combined effects of oxygen content and temperature on the strain hardening exponent and reduction in area was investigated. Alloys containing 0.83 at. pct or less do not exhibit a brittle-ductile transition down to 4.2 K but a 1 at. pct alloy is brittle at 77 K and a 1.25 at. pct alloy has a BDTT between 135 and 195 K

Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

International Nuclear Information System (INIS)

Tutcu, Semra; Serter, Selim; Kaya, Yavuz; Kara, Eray; Nese, Nalan; Pekindil, Goekhan; Coskun, Teoman

2010-01-01

Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

Application of rotatable central composite design in the preparation and optimization of poly(lactic-co-glycolic acid) nanoparticles for controlled delivery of paclitaxel.

Science.gov (United States)

Kollipara, Sivacharan; Bende, Girish; Movva, Snehalatha; Saha, Ranendra

2010-11-01

Polymeric carrier systems of paclitaxel (PCT) offer advantages over only available formulation Taxol® in terms of enhancing therapeutic efficacy and eliminating adverse effects. The objective of the present study was to prepare poly (lactic-co-glycolic acid) nanoparticles containing PCT using emulsion solvent evaporation technique. Critical factors involved in the processing method were identified and optimized by scientific, efficient rotatable central composite design aiming at low mean particle size and high entrapment efficiency. Twenty different experiments were designed and each formulation was evaluated for mean particle size and entrapment efficiency. The optimized formulation was evaluated for in vitro drug release, and absorption characteristics were studied using in situ rat intestinal permeability study. Amount of polymer and duration of ultrasonication were found to have significant effect on mean particle size and entrapment efficiency. First-order interactions of amount of miglyol with amount of polymer were significant in case of mean particle size, whereas second-order interactions of polymer were significant in mean particle size and entrapment efficiency. The developed quadratic model showed high correlation (R(2) > 0.85) between predicted response and studied factors. The optimized formulation had low mean particle size (231.68 nm) and high entrapment efficiency (95.18%) with 4.88% drug content. The optimized formulation showed controlled release of PCT for more than 72 hours. In situ absorption study showed faster and enhanced extent of absorption of PCT from nanoparticles compared to pure drug. The poly (lactic-co-glycolic acid) nanoparticles containing PCT may be of clinical importance in enhancing its oral bioavailability.

Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

Energy Technology Data Exchange (ETDEWEB)

Tutcu, Semra [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Serter, Selim, E-mail: serterselim@gmail.co [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Kaya, Yavuz; Kara, Eray [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Nese, Nalan [Department of Pathology, Celal Bayar University, School of Medicine, Manisa (Turkey); Pekindil, Goekhan [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Coskun, Teoman [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey)

2010-08-15

Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

Soluble membrane receptors, interleukin 6, procalcitonin and C reactive protein as prognostic markers in patients with severe sepsis and septic shock.

Directory of Open Access Journals (Sweden)

Juan-Jesús Ríos-Toro

Full Text Available The objective of this study was to explore the diagnostic and prognostic value of soluble triggering receptor expressed on myeloid cell 1 (sTREM-1, soluble cluster of differentiation 14 (sCD14, soluble cluster of differentiation 163 (sCD163, interleukin-6 (IL-6, procalcitonin (PCT, and C-reactive protein (CRP serum levels for patients with severe sepsis and septic shock in an intensive care unit (ICU.Fifty patients admitted at the ICU with the diagnosis of severe sepsis or septic shock were studied. SOFA and APACHE II scores as well as serum biomarkers were measured at days 0, 2 and 5. The influence of these variables on 28-day mortality was analyzed. Twenty healthy individuals served as controls.Baseline serum concentrations of sTREM-1, sCD163, IL-6 and PCT correlated with SOFA score. Only sTREM-1 levels correlated with APACHE II score. The 28-day mortality rate for all patients was 42%. The absence of risk factors for infection, presence of septic shock, baseline values of sCD14 and decrease of PCT and IL-6 from baseline to day 5 were variables associated to mortality in the univariate analysis. The unique independent factor associated to mortality in the multivariate analysis was a decrease of PCT higher than 50% from days 0 to 5.Serum levels of sTREM-1 are correlated with the severity of sepsis. A 50% decrease of PCT was the unique variable associated with survival in the multivariate analysis.

Inter-fractional Target Displacement in the Prostate Image-Guided Radiotherapy using Cone Beam Computed Tomography

International Nuclear Information System (INIS)

Dong, Kap Sang; Back, Chang Wook; Jeong, Yun Jeong; Bae, Jae Beom; Choi, Young Eun; Sung, Ki Hoon

2016-01-01

To quantify the inter-fractional variation in prostate displacement and their dosimetric effects for prostate cancer treatment. A total of 176 daily cone-beam CT (CBCT) sets acquired for 6 prostate cancer patients treated with volumetric-modulated arc therapy (VMAT) were retrospectively reviewed. For each patient, the planning CT (pCT) was registered to each daily CBCT by aligning the bony anatomy. The prostate, rectum, and bladder were delineated on daily CBCT, and the contours of these organs in the pCT were copied to the daily CBCT. The concordance of prostate displacement, deformation, and size variation between pCT and daily CBCT was evaluated using the Dice similarity coefficient (DSC). The mean volume of prostate was 37.2 cm3 in the initial pCT, and the variation was around ±5% during the entire course of treatment for all patients. The mean DSC was 89.9%, ranging from 70% to 100% for prostate displacement. Although the volume change of bladder and rectum per treatment fraction did not show any correlation with the value of DSC (r=-0.084, p=0.268 and r=-0.162, p=0.032, respectively), a decrease in the DSC value was observed with increasing volume change of the bladder and rectum (r=-0.230,p=0.049 and r=-0.240,p=0.020, respectively). Consistency of the volume of the bladder and rectum cannot guarantee the accuracy of the treatment. Our results suggest that patient setup with the registration between the pCT and daily CBCT should be considered aligning soft tissue

Bragg peak prediction from quantitative proton computed tomography using different path estimates

International Nuclear Information System (INIS)

Wang Dongxu; Mackie, T Rockwell; Tome, Wolfgang A

2011-01-01

This paper characterizes the performance of the straight-line path (SLP) and cubic spline path (CSP) as path estimates used in reconstruction of proton computed tomography (pCT). The GEANT4 Monte Carlo simulation toolkit is employed to simulate the imaging phantom and proton projections. SLP, CSP and the most-probable path (MPP) are constructed based on the entrance and exit information of each proton. The physical deviations of SLP, CSP and MPP from the real path are calculated. Using a conditional proton path probability map, the relative probability of SLP, CSP and MPP are calculated and compared. The depth dose and Bragg peak are predicted on the pCT images reconstructed using SLP, CSP, and MPP and compared with the simulation result. The root-mean-square physical deviations and the cumulative distribution of the physical deviations show that the performance of CSP is comparable to MPP while SLP is slightly inferior. About 90% of the SLP pixels and 99% of the CSP pixels lie in the 99% relative probability envelope of the MPP. Even at an imaging dose of ∼0.1 mGy the proton Bragg peak for a given incoming energy can be predicted on the pCT image reconstructed using SLP, CSP, or MPP with 1 mm accuracy. This study shows that SLP and CSP, like MPP, are adequate path estimates for pCT reconstruction, and therefore can be chosen as the path estimation method for pCT reconstruction, which can aid the treatment planning and range prediction of proton radiation therapy.

Bragg peak prediction from quantitative proton computed tomography using different path estimates

Energy Technology Data Exchange (ETDEWEB)

Wang Dongxu; Mackie, T Rockwell; Tome, Wolfgang A, E-mail: tome@humonc.wisc.edu [Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705 (United States)

2011-02-07

This paper characterizes the performance of the straight-line path (SLP) and cubic spline path (CSP) as path estimates used in reconstruction of proton computed tomography (pCT). The GEANT4 Monte Carlo simulation toolkit is employed to simulate the imaging phantom and proton projections. SLP, CSP and the most-probable path (MPP) are constructed based on the entrance and exit information of each proton. The physical deviations of SLP, CSP and MPP from the real path are calculated. Using a conditional proton path probability map, the relative probability of SLP, CSP and MPP are calculated and compared. The depth dose and Bragg peak are predicted on the pCT images reconstructed using SLP, CSP, and MPP and compared with the simulation result. The root-mean-square physical deviations and the cumulative distribution of the physical deviations show that the performance of CSP is comparable to MPP while SLP is slightly inferior. About 90% of the SLP pixels and 99% of the CSP pixels lie in the 99% relative probability envelope of the MPP. Even at an imaging dose of {approx}0.1 mGy the proton Bragg peak for a given incoming energy can be predicted on the pCT image reconstructed using SLP, CSP, or MPP with 1 mm accuracy. This study shows that SLP and CSP, like MPP, are adequate path estimates for pCT reconstruction, and therefore can be chosen as the path estimation method for pCT reconstruction, which can aid the treatment planning and range prediction of proton radiation therapy.

Bragg peak prediction from quantitative proton computed tomography using different path estimates

Science.gov (United States)

Wang, Dongxu; Mackie, T Rockwell

2015-01-01

This paper characterizes the performance of the straight-line path (SLP) and cubic spline path (CSP) as path estimates used in reconstruction of proton computed tomography (pCT). The GEANT4 Monte Carlo simulation toolkit is employed to simulate the imaging phantom and proton projections. SLP, CSP and the most-probable path (MPP) are constructed based on the entrance and exit information of each proton. The physical deviations of SLP, CSP and MPP from the real path are calculated. Using a conditional proton path probability map, the relative probability of SLP, CSP and MPP are calculated and compared. The depth dose and Bragg peak are predicted on the pCT images reconstructed using SLP, CSP, and MPP and compared with the simulation result. The root-mean-square physical deviations and the cumulative distribution of the physical deviations show that the performance of CSP is comparable to MPP while SLP is slightly inferior. About 90% of the SLP pixels and 99% of the CSP pixels lie in the 99% relative probability envelope of the MPP. Even at an imaging dose of ~0.1 mGy the proton Bragg peak for a given incoming energy can be predicted on the pCT image reconstructed using SLP, CSP, or MPP with 1 mm accuracy. This study shows that SLP and CSP, like MPP, are adequate path estimates for pCT reconstruction, and therefore can be chosen as the path estimation method for pCT reconstruction, which can aid the treatment planning and range prediction of proton radiation therapy. PMID:21212472

Inter-fractional Target Displacement in the Prostate Image-Guided Radiotherapy using Cone Beam Computed Tomography

Energy Technology Data Exchange (ETDEWEB)

Dong, Kap Sang; Back, Chang Wook; Jeong, Yun Jeong; Bae, Jae Beom; Choi, Young Eun; Sung, Ki Hoon [Dept. of Radiation Oncology, Gachon University Gil Medical Center, Incheon (Korea, Republic of)

2016-12-15

To quantify the inter-fractional variation in prostate displacement and their dosimetric effects for prostate cancer treatment. A total of 176 daily cone-beam CT (CBCT) sets acquired for 6 prostate cancer patients treated with volumetric-modulated arc therapy (VMAT) were retrospectively reviewed. For each patient, the planning CT (pCT) was registered to each daily CBCT by aligning the bony anatomy. The prostate, rectum, and bladder were delineated on daily CBCT, and the contours of these organs in the pCT were copied to the daily CBCT. The concordance of prostate displacement, deformation, and size variation between pCT and daily CBCT was evaluated using the Dice similarity coefficient (DSC). The mean volume of prostate was 37.2 cm3 in the initial pCT, and the variation was around ±5% during the entire course of treatment for all patients. The mean DSC was 89.9%, ranging from 70% to 100% for prostate displacement. Although the volume change of bladder and rectum per treatment fraction did not show any correlation with the value of DSC (r=-0.084, p=0.268 and r=-0.162, p=0.032, respectively), a decrease in the DSC value was observed with increasing volume change of the bladder and rectum (r=-0.230,p=0.049 and r=-0.240,p=0.020, respectively). Consistency of the volume of the bladder and rectum cannot guarantee the accuracy of the treatment. Our results suggest that patient setup with the registration between the pCT and daily CBCT should be considered aligning soft tissue.

Plasma neutrophil gelatinase-associated lipocalin: a marker of acute pyelonephritis in children.

Science.gov (United States)

Kim, Byung Kwan; Yim, Hyung Eun; Yoo, Kee Hwan

2017-03-01

This study was designed to compare the diagnostic accuracy of plasma neutrophil gelatinase-associated lipocalin (NGAL) with procalcitonin (PCT), C-reactive protein (CRP), and white blood cells (WBCs) for predicting acute pyelonephritis (APN) in children with febrile urinary tract infections (UTIs). In total, 138 children with febrile UTIs (APN 59, lower UTI 79) were reviewed retrospectively. Levels of NGAL, PCT, CRP, and WBCs in blood were measured on admission. The diagnostic accuracy of the biomarkers was investigated. Independent predictors of APN were identified by multivariate logistic regression analysis. Receiver operating curve (ROC) analyses showed good diagnostic profiles of NGAL, PCT, CRP, and WBCs for identifying APN [area under the curve (AUC) 0.893, 0.855, 0.879, and 0.654, respectively]. However, multivariate analysis revealed only plasma NGAL level was an independent predictor of APN (P = 0.006). At the best cutoff values of all examined biomarkers for identifying APN, sensitivity (86 %), specificity (85 %), positive predictive value (81 %), and negative predictive value (89 %) of plasma NGAL levels were the highest. The optimal NGAL cutoff value was 117 ng/ml. The positive likelihood ratio [odds ratio (OR) 5.69, 95 % confidence interval (CI) 3.56-8.78], and negative likelihood ratio (OR 0.16, 95 % CI 0.08-0.29) of plasma NGAL for APN diagnosis also showed it seemed to be more accurate than serum PCT, CRP, and WBCs. Plasma NGAL can be more useful than serum PCT, CRP, and WBC levels for identifying APN in children with febrile UTIs.

Evaluation of diagnostic value of procalcitonin in pediatric acute pyelonephritis

Directory of Open Access Journals (Sweden)

Simin Sadeghi-bojd

2012-05-01

Full Text Available Background and Aim: Urinary tract infection (UTI in children is among the prevalent infections of childhood, which occurs due to growth of bacteria in the urinary tract. The aim of this study was to evaluate the usefulness of procalcitonin (PCT as a reliable marker for distinguishing urinary tract infection (UTI with or without renal parenchyma (cystitis. Materials and Methods: Eighty children, who were suspicious of having UTI and had been referred to Ali Ibne Abitaleb hospital (in Zahedan or pediatric clinics (June 2007- Oct 2009 were included in the study after their urine culture revealed their infection. Besides, their clinical and lab symptoms including erythrocyte sedimentation rate (ESR, C– reactive protein (CRP, serum WBC, and serum procalcitonin (PCT were recorded. The patients were divided into two groups based on their lab clinical symptoms and radio-isotope scans, namely acute pyelonephritis and acute cystitis (lower UTI. Serum procalcitonin was measured in these cases in a semi-quantitative manner. Results: Fifty children with mean age of 4.89±3.50 years were compared with 30 children with mean age of 5.20±3.07 years. ESR, WBC, and PCT were significantly higher in patients with upper UTI (P<0.001 , but CRP was not significantly different in the two groups. PCT, which was semi-quantitatively measured, when lower than 0.5 had a relationship with sensitivity, specificity, positive predictive value, and negative value of 72%, 83.3%, 87.8%, and 64.1% respectively. When PCT was more than 2, the relationship with the mentioned features was 50%, 96.6%, 96.2%, and 53.7%, respectively. The relationships in these two domains can both be assistant in differentiating pyelonephritis from cystitis. Conclusion: PCT was more sensitive and specific for the diagnosis of upper versus lower UTI compared with CRP, and it can be a better marker than CRP for early prediction of febrile pyelonephritis in children.

Does psychosocial competency training for junior physicians working in pediatric medicine improve individual skills and perceived job stress.

Science.gov (United States)

Bernburg, Monika; Baresi, Lisa; Groneberg, David; Mache, Stefanie

2016-12-01

Pediatricians' job performance, work engagement, and job satisfaction are essential for both the individual physician and quality of care for their little patients and parents. Therefore, it is important to maintain or possibly augment pediatricians' individual and professional competencies. In this study, we developed and implemented a psychosocial competency training (PCT) teaching different psychosocial competencies and stress coping techniques. We investigated (1) the influence of the PCT on work-related characteristics: stress perception, work engagement, job satisfaction and (2) explored pediatricians' outcomes and satisfaction with PCT. Fifty-four junior physicians working in pediatric hospital departments participated in the training and were randomized in an intervention (n = 26) or a control group (n = 28). In the beginning, at follow-up 1 and 2, both groups answered a self-rated questionnaire on perceived training outcomes and work-related factors. The intervention group showed that their job satisfaction significantly increased while perceived stress scores decreased after taking part in the PCT. No substantial changes were observed with regard to pediatricians' work engagement. Participating physicians evaluated PCT with high scores for training design, content, received outcome, and overall satisfaction with the training. Professional psychosocial competency training could improve junior pediatricians' professional skills, reduce stress perception, increase their job satisfaction, and psychosocial skills. In addition, this study indicates that the PCT is beneficial to be implemented as a group training program for junior pediatricians at work. What is Known: • Junior pediatricians often report experiencing high levels of job strain and little supervisory support. • High levels of job demands make pediatricians vulnerable for mental health problems and decreased work ability. What is New: • Development, implementation, and evaluation of a

SU-E-J-106: The Use of Deformable Image Registration with Cone-Beam CT for a Better Evaluation of Cumulative Dose to Organs

Energy Technology Data Exchange (ETDEWEB)

Fillion, O; Gingras, L; Archambault, L [Universite Laval, Quebec, Quebec (Canada); Centre de recherche du CHU de Quebec, Quebec, Quebec (Canada); Centre de recherche sur le cancer, Quebec, Quebec (Canada)

2015-06-15

Purpose: The knowledge of dose accumulation in the patient tissues in radiotherapy helps in determining the treatment outcomes. This project aims at providing a workflow to map cumulative doses that takes into account interfraction organ motion without the need for manual re-contouring. Methods: Five prostate cancer patients were studied. Each patient had a planning CT (pCT) and 5 to 13 CBCT scans. On each series, a physician contoured the prostate, rectum, bladder, seminal vesicles and the intestine. First, a deformable image registration (DIR) of the pCTs onto the daily CBCTs yielded registered CTs (rCT) . This rCT combined the accurate CT numbers of the pCT with the daily anatomy of the CBCT. Second, the original plans (220 cGy per fraction for 25 fractions) were copied on the rCT for dose re-calculation. Third, the DIR software Elastix was used to find the inverse transform from the rCT to the pCT. This transformation was then applied to the rCT dose grid to map the dose voxels back to their pCT location. Finally, the sum of these deformed dose grids for each patient was applied on the pCT to calculate the actual dose delivered to organs. Results: The discrepancy between the planned D98 and D2 and these indices re-calculated on the rCT, are, on average, of −1 ± 1 cGy and 1 ± 2 cGy per fraction, respectively. For fractions with large anatomical motion, the D98 discrepancy on the re-calculated dose grid mapped onto the pCT can raise to −17 ± 4 cGy. The obtained cumulative dose distributions illustrate the same behavior. Conclusion: This approach allowed the evaluation of cumulative doses to organs with the help of uncontoured daily CBCT scans. With this workflow, the easy evaluation of doses delivered for EBRT treatments could ultimately lead to a better follow-up of prostate cancer patients.

SU-E-J-106: The Use of Deformable Image Registration with Cone-Beam CT for a Better Evaluation of Cumulative Dose to Organs

International Nuclear Information System (INIS)

Fillion, O; Gingras, L; Archambault, L

2015-01-01

Purpose: The knowledge of dose accumulation in the patient tissues in radiotherapy helps in determining the treatment outcomes. This project aims at providing a workflow to map cumulative doses that takes into account interfraction organ motion without the need for manual re-contouring. Methods: Five prostate cancer patients were studied. Each patient had a planning CT (pCT) and 5 to 13 CBCT scans. On each series, a physician contoured the prostate, rectum, bladder, seminal vesicles and the intestine. First, a deformable image registration (DIR) of the pCTs onto the daily CBCTs yielded registered CTs (rCT) . This rCT combined the accurate CT numbers of the pCT with the daily anatomy of the CBCT. Second, the original plans (220 cGy per fraction for 25 fractions) were copied on the rCT for dose re-calculation. Third, the DIR software Elastix was used to find the inverse transform from the rCT to the pCT. This transformation was then applied to the rCT dose grid to map the dose voxels back to their pCT location. Finally, the sum of these deformed dose grids for each patient was applied on the pCT to calculate the actual dose delivered to organs. Results: The discrepancy between the planned D98 and D2 and these indices re-calculated on the rCT, are, on average, of −1 ± 1 cGy and 1 ± 2 cGy per fraction, respectively. For fractions with large anatomical motion, the D98 discrepancy on the re-calculated dose grid mapped onto the pCT can raise to −17 ± 4 cGy. The obtained cumulative dose distributions illustrate the same behavior. Conclusion: This approach allowed the evaluation of cumulative doses to organs with the help of uncontoured daily CBCT scans. With this workflow, the easy evaluation of doses delivered for EBRT treatments could ultimately lead to a better follow-up of prostate cancer patients

Calorimetric Investigation of Thermal Stability of 304H Cu (Fe-17.7Cr-9.3Ni-2.95Cu-0.91Mn-0.58Nb-0.24Si-0.1C-0.12N-Wt Pct) Austenitic Stainless Steel

Science.gov (United States)

Tripathy, Haraprasanna; Subramanian, Raju; Hajra, Raj Narayan; Rai, Arun Kumar; Rengachari, Mythili; Saibaba, Saroja; Jayakumar, Tammana

2016-12-01

The sequence of phase instabilities that take place in a Fe-17.7Cr-9.3Ni-0.58Nb-2.95Cu-0.12N (wt pct) austenitic stainless steel (304H Cu grade) as a function of temperature has been investigated using dynamic calorimetry. The results obtained from this investigation are supplemented by Thermocalc-based equilibrium and Scheil-Gulliver nonequilibrium solidification simulation. The following phase transformation sequence is found upon slow cooling from liquid: L → L + γ → L + γ + MX → γ + MX + δ → γ +MX + M23C6 → γ + MX + M23C6 + Cu. Under slow cooling, the solidification follows austenite + ferrite (AF) mode, which is in accordance with Thermocalc prediction and Scheil-Gulliver simulation. However, higher cooling rates result in skeletal δ-ferrite formation, due to increased segregation tendency of Nb and Cr to segregate to interdendritic liquid. The solidification mode is found to depend on combined Nb + Cu content. Experimental estimates of enthalpy change associated with melting and secondary phase precipitation are also obtained. In addition a semi-quantitative study on the dissolution kinetics of M23C6 type carbides has also been investigated. The standard solution treatment at 1413 K (1140 °C) is found to be adequate to dissolve both Cu and M23C6 into γ-austenite; but the complete dissolution of MX type carbonitrides occurs near the melting region.

Assessment of Intervention by a Palliative Care Team Working in a Japanese General Hospital: A Retrospective Study.

Science.gov (United States)

Amano, Koji; Morita, Tatsuya; Tatara, Ryohei; Katayama, Hirofumi; Aiki, Sayo; Kitada, Namiki; Fumimoto, Hiromi; Sato, Emi

2015-09-01

Our objective was to explore the effectiveness of a palliative care team (PCT) by investigating potential differences in opioid prescription between patients who had had PCT involvement before admission to an inpatient hospice and those who had not. A total of 221 patients met the criteria; they were divided into an intervention group (n = 140) and a control group (n = 81). The daily dose of opioid before admission to the hospice was significantly higher in the intervention group (P < .001). The difference between the maximum opioid dose and the initial dose, the rate of increase in opioids until death, and the length of stay in the hospice were not significantly different between the groups. A PCT contributes to more appropriate use of opioids before admission to a hospice. © The Author(s) 2014.

PUMA: An Operating System for Massively Parallel Systems

Directory of Open Access Journals (Sweden)

Stephen R. Wheat

1994-01-01

Full Text Available This article presents an overview of PUMA (Performance-oriented, User-managed Messaging Architecture, a message-passing kernel for massively parallel systems. Message passing in PUMA is based on portals – an opening in the address space of an application process. Once an application process has established a portal, other processes can write values into the portal using a simple send operation. Because messages are written directly into the address space of the receiving process, there is no need to buffer messages in the PUMA kernel and later copy them into the applications address space. PUMA consists of two components: the quintessential kernel (Q-Kernel and the process control thread (PCT. Although the PCT provides management decisions, the Q-Kernel controls access and implements the policies specified by the PCT.

Recrystallization in Commercially Pure Aluminum

DEFF Research Database (Denmark)

Bay, Bent; Hansen, Niels

1984-01-01

Recrystallization behavior in commercial aluminum with a purity of 99.4 pct was studied by techniques such as high voltage electron microscopy, 100 kV transmission electron microscopy, and light microscopy. Sample parameters were the initial grain size (290 and 24 microns) and the degree of defor......Recrystallization behavior in commercial aluminum with a purity of 99.4 pct was studied by techniques such as high voltage electron microscopy, 100 kV transmission electron microscopy, and light microscopy. Sample parameters were the initial grain size (290 and 24 microns) and the degree...... are discussed and compared with results from an earlier study1 covering the recrystallization behavior of commercial aluminum of the same purity deformed at higher degrees of deformation (50 to 90 pct reduction in thickness by cold-rolling)....

Aspectos da proteção cerebral em pacientes submetidos a tromboendarterectomia pulmonar com hipotermia profunda e parada circulatória intermitente

Directory of Open Access Journals (Sweden)

HUEB Alexandre C.

2000-01-01

Full Text Available INTRODUÇÃO: A tromboendarterectomia pulmonar é utilizada como método bem estabelecido para aliviar a hipertensão pulmonar nos casos de tromboembolismo pulmonar crônico. A dificuldade que se apresenta é conciliar o tempo relativamente exíguo de parada circulatória total (PCT hipotérmica com a completa desobstrução das artérias pulmonares, sob pena de danos neurológicos. CASUÍSTICA E MÉTODOS: No período de março de 1998 a abril de 1999 (13 meses, 8 pacientes, 5 do sexo masculino, 1 de cor negra, com idade variando entre 25 a 56 anos (média 46,2 anos e com diagnóstico angiográfico de tromboembolismo pulmonar, foram submetidos a tromboendarterectomia pulmonar uni ou bilateral por tromboembolismo pulmonar crônico (TEP. Instalado o circuito extracorpóreo e incisada a artéria pulmonar, procede-se à PCT e, aproximadamente a cada 20 minutos de procedimento, intermitentemente, o fluxo da circulação extracorpórea (CEC é restabelecido a 14º C por um período de 15 minutos objetivando-se a reperfusão cerebral e corpórea. Sucessivas paradas circulatórias total são realizadas e tantas quanto forem necessárias até a remoção de todos os trombos da artéria pulmonar. RESULTADOS: Não foram registrados óbitos no transoperatório. Um paciente faleceu no 30º dia de pós-operatório (PO devido a broncopneumonia que evoluiu para sepse. Os 8 pacientes foram submetidos a CEC e PCT hipotérmica, sendo que em 5 (62,5% foram necessárias 4 PCT e em 3 (37,5% apenas 3 PCT, com média de 3,6 PCT. O tempo total de CEC variou de 210 a 255 minutos, com média de 225 minutos. O tempo de PCT hipotérmica variou de 58 a 88 minutos, com média de 76,7 minutos e o período de PCT por paciente variou de 18 a 24 minutos, com média de 20,5 minutos. Em todos os pacientes foram realizadas tomografias de crânio, que não revelaram nenhuma alteração anatômica, assim como o exame físico não revelou déficit motor ou rebaixamento do sens

Assessment of Open-Angle Glaucoma Peripapillary and Macular Choroidal Thickness Using Swept-Source Optical Coherence Tomography (SS-OCT.

Directory of Open Access Journals (Sweden)

Yong Ju Song

Full Text Available To compare peripapillary and macular choroidal thickness (PCT and MCT between open-angle glaucoma (OAG and normal controls using swept-source optical coherence tomography (SS-OCT, and to evaluate global and localized relationships between choroidal thickness and various factors in OAG, also using SS-OCT.In this cross-sectional comparative study, 134 OAG patients and 73 normal controls were examined. PCT (global, 12 clock-hour sectors, MCT (global, six sectors were measured by SS-OCT. The difference in choroidal thickness between the OAG patients and the normal controls was analyzed. The relationships between choroidal thickness and various factors including age, sex, spherical equivalent (SE, axial length (AXL, central corneal thickness (CCT, intraocular pressure (IOP, peripapillary retinal nerve fiber layer thickness (pRNFLT, visual field mean deviation (MD, ganglion cell-inner plexiform layer thickness (GCIPLT, and disc area were analyzed by univariate and multivariate linear regression. Global and regional analyses were performed in 12 segments of the peripapillary circle and in six sectors of the macula.There were significant differences in global PCT and MCT between the OAG patients and the normal controls (115.22±41.17 vs. 138.89±44.70, P<0.001, (184.36±57.15 vs. 209.25±61.11, P = 0.004. The difference in global PCT remained, both after adjusting for age, AXL (117.08±3.45 vs. 135.47±4.70, P = 0.002 and also after adjusting for age, AXL, disc area (117.46±3.46 vs. 135.67±4.67, P = 0.002. But the difference in global MCT did not remain after adjusting for age, AXL, SE (188.18±4.46 vs. 202.25±6.08, P = 0.066. PCT showed significant differences between the groups in all of the 12 clock-hour sectors. These differences remained after adjusting for age, AXL and for age, AXL, disc area, with the exception of the 10 o'clock (o/c sector. MCT in six sectors showed differences between the two groups, but they did not remain after adjusting

Towards a meaningful metric for the quantification of GHG emissions of electric vehicles (EVs)

International Nuclear Information System (INIS)

Manjunath, Archana; Gross, George

2017-01-01

A key motivator for wider deployment of electric vehicles (EVs) – vehicles that are fully powered by battery charged from grid electricity – is to bring about environmental cleanliness. This goal is based on the fact that EVs produce zero tailpipe emissioon the associated carbon emissins. However, the generation and transmission of the charge electricity produce emissions that are not explicitly accounted by current measurement metrics for EV greenhouse gas (GHG) emissions and as such, the notion of environmental cleanliness of EVs becomes questionable. In this paper, we propose a comprehensive metric to quantify the actual environmental impacts of EVs. The new metric that we call the electric vehicle emissions index (EVEI) captures CO_2 emissions in the electricity production to consumption stages. Our metric is the first that provides transparency in the comparison of total emissions among various EV models, as well as in the side-by-side comparison of an EV with a gasoline vehicle (GV). Illustrative results indicate that the actual environmental impacts of an EV may show wide spatial variations and in some case, these impacts may be even greater than that of GV. Such insights that the EVEI provides may be useful in a wide range of applications, particularly in policy and incentive formulation. - Highlights: • We propose the Electric Vehicle Emission Index (EVEI) metric. • EVEI indicates the EV environmental impacts w.r.t gasoline vehicles (GVs). • Fuel economy and resource mix are the major contributors to emissions. • Results indicate EVs may prove to be dirtier than GVs in certain areas of usage. • Insights may prove to be valuable to policy and incentive formulation.

Hvorfor går Liberal Alliance frem?

DEFF Research Database (Denmark)

Kurrild-Klitgaard, Peter

2010-01-01

Liberal Alliance lå for kun lidt over et år siden ofte til 0 pct. i meningsmålingerne, men har siden haft et bemærkelsesværdigt comeback uden lige i nyere dansk politisk historie. Først fik man trukket sig over den symbolske »spærregrænse« på 2,0 pct., og i den seneste meningsmåling (fra You...

Hvorfor går Liberal Alliance frem?

DEFF Research Database (Denmark)

Kurrild-Klitgaard, Peter

2010-01-01

Liberal Alliance lå for kun lidt over et år siden ofte til 0 pct. i meningsmålingerne, men har siden haft et bemærkelsesværdigt comeback uden lige i nyere dansk politisk historie. Først fik man trukket sig over den symbolske »spærregrænse« på 2,0 pct., og i den seneste meningsmåling ( fra You...

A scattering-based over-land rainfall retrieval algorithm for South Korea using GCOM-W1/AMSR-2 data

Science.gov (United States)

Kwon, Young-Joo; Shin, Hayan; Ban, Hyunju; Lee, Yang-Won; Park, Kyung-Ae; Cho, Jaeil; Park, No-Wook; Hong, Sungwook

2017-08-01

Heavy summer rainfall is a primary natural disaster affecting lives and properties in the Korean Peninsula. This study presents a satellite-based rainfall rate retrieval algorithm for the South Korea combining polarization-corrected temperature ( PCT) and scattering index ( SI) data from the 36.5 and 89.0 GHz channels of the Advanced microwave Scanning Radiometer 2 (AMSR-2) onboard the Global Change Observation Mission (GCOM)-W1 satellite. The coefficients for the algorithm were obtained from spatial and temporal collocation data from the AMSR-2 and groundbased automatic weather station rain gauges from 1 July - 30 August during the years, 2012-2015. There were time delays of about 25 minutes between the AMSR-2 observations and the ground raingauge measurements. A new linearly-combined rainfall retrieval algorithm focused on heavy rain for the PCT and SI was validated using ground-based rainfall observations for the South Korea from 1 July - 30 August, 2016. The validation presented PCT and SI methods showed slightly improved results for rainfall > 5 mm h-1 compared to the current ASMR-2 level 2 data. The best bias and root mean square error (RMSE) for the PCT method at AMSR-2 36.5 GHz were 2.09 mm h-1 and 7.29 mm h-1, respectively, while the current official AMSR-2 rainfall rates show a larger bias and RMSE (4.80 mm h-1 and 9.35 mm h-1, respectively). This study provides a scatteringbased over-land rainfall retrieval algorithm for South Korea affected by stationary front rain and typhoons with the advantages of the previous PCT and SI methods to be applied to a variety of spaceborne passive microwave radiometers.

Comparison between perfusion computed tomography and dynamic contrast-enhanced magnetic resonance imaging in assessing glioblastoma microvasculature

Energy Technology Data Exchange (ETDEWEB)

Jia, Zhong Zheng, E-mail: jzz2397@163.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China); Shi, Wei, E-mail: sw740104@hotmail.com [Department of Neurosurgery, Affiliated Hospital of Nantong University, 20 Xisi Road, Nantong 226001, Jiangsu (China); Shi, Jin Long, E-mail: shij_ns@163.com [Department of Neurosurgery, Affiliated Hospital of Nantong University, 20 Xisi Road, Nantong 226001, Jiangsu (China); Shen, Dan Dan, E-mail: 1021121084@qq.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China); Gu, Hong Mei, E-mail: guhongmei71@163.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China); Zhou, Xue Jun, E-mail: 56516400@qq.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China)

2017-02-15

Purpose: Perfusion computed tomography (PCT) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) provide independent measurements of biomarkers related to tumor perfusion. The aim of this study was to compare the two techniques in assessing glioblastoma microvasculature. Materials and methods: Twenty-five patients diagnosed with glioblastoma (14 males and 11 females; 51 ± 11 years old, ranging from 33 to 70 years) were includede in this prospective study. All patients underwent both PCT and DCE-MRI. Imaging was performed on a 256-slice CT scanner and a 3-T MRI system. PCT yielded permeability surface-area product (PS) using deconvolution physiological models; meanwhile, DCE-MRI determined volume transfer constant (K{sup trans}) using the Tofts-Kermode compartment model. All cases were submitted to surgical intervention, and CD105-microvascular density (CD105-MVD) was measured in each glioblastoma specimen. Then, Spearman’s correlation coefficients and Bland-Altman plots were obtained for PS, K{sup trans} and CD105-MVD. P < 0.05 was considered statistically significant. Results: Tumor PS and K{sup trans} values were correlated with CD105-MVD (r = 0.644, P < 0.001; r = 0.683, P < 0.001). In addition, PS was correlated with K{sup trans} in glioblastoma (r = 0.931, P < 0.001). Finally, Bland-Altman plots showed no significant differences between PS and K{sup trans} (P = 0.063). Conclusion: PCT and DCE-MRI measurements of glioblastoma perfusion biomarkers have similar results, suggesting that both techniques may have comparable utility. Therefore, PCT may serve as an alternative modality to DCE-MRI for the in vivo evaluation of glioblastoma microvasculature.

Diagnostic accuracy of procalcitonin in critically ill immunocompromised patients

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Legriel Stéphane

2011-08-01

Full Text Available Abstract Background Recognizing infection is crucial in immunocompromised patients with organ dysfunction. Our objective was to assess the diagnostic accuracy of procalcitonin (PCT in critically ill immunocompromised patients. Methods This prospective, observational study included patients with suspected sepsis. Patients were classified into one of three diagnostic groups: no infection, bacterial sepsis, and nonbacterial sepsis. Results We included 119 patients with a median age of 54 years (interquartile range [IQR], 42-68 years. The general severity (SAPSII and organ dysfunction (LOD scores on day 1 were 45 (35-62.7 and 4 (2-6, respectively, and overall hospital mortality was 32.8%. Causes of immunodepression were hematological disorders (64 patients, 53.8%, HIV infection (31 patients, 26%, and solid cancers (26 patients, 21.8%. Bacterial sepsis was diagnosed in 58 patients and nonbacterial infections in nine patients (7.6%; 52 patients (43.7% had no infection. PCT concentrations on the first ICU day were higher in the group with bacterial sepsis (4.42 [1.60-22.14] vs. 0.26 [0.09-1.26] ng/ml in patients without bacterial infection, P 0.5 ng/ml had 100% sensitivity but only 63% specificity for diagnosing bacterial sepsis. The area under the receiver operating characteristic (ROC curve was 0.851 (0.78-0.92. In multivariate analyses, PCT concentrations > 0.5 ng/ml on day 1 independently predicted bacterial sepsis (odds ratio, 8.6; 95% confidence interval, 2.53-29.3; P = 0.0006. PCT concentrations were not significantly correlated with hospital mortality. Conclusion Despite limited specificity in critically ill immunocompromised patients, PCT concentrations may help to rule out bacterial infection.

Diagnostic accuracy of procalcitonin in critically ill immunocompromised patients.

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Bele, Nicolas; Darmon, Michael; Coquet, Isaline; Feugeas, Jean-Paul; Legriel, Stéphane; Adaoui, Nadir; Schlemmer, Benoît; Azoulay, Elie

2011-08-24

Recognizing infection is crucial in immunocompromised patients with organ dysfunction. Our objective was to assess the diagnostic accuracy of procalcitonin (PCT) in critically ill immunocompromised patients. This prospective, observational study included patients with suspected sepsis. Patients were classified into one of three diagnostic groups: no infection, bacterial sepsis, and nonbacterial sepsis. We included 119 patients with a median age of 54 years (interquartile range [IQR], 42-68 years). The general severity (SAPSII) and organ dysfunction (LOD) scores on day 1 were 45 (35-62.7) and 4 (2-6), respectively, and overall hospital mortality was 32.8%. Causes of immunodepression were hematological disorders (64 patients, 53.8%), HIV infection (31 patients, 26%), and solid cancers (26 patients, 21.8%). Bacterial sepsis was diagnosed in 58 patients and nonbacterial infections in nine patients (7.6%); 52 patients (43.7%) had no infection. PCT concentrations on the first ICU day were higher in the group with bacterial sepsis (4.42 [1.60-22.14] vs. 0.26 [0.09-1.26] ng/ml in patients without bacterial infection, P 0.5 ng/ml had 100% sensitivity but only 63% specificity for diagnosing bacterial sepsis. The area under the receiver operating characteristic (ROC) curve was 0.851 (0.78-0.92). In multivariate analyses, PCT concentrations > 0.5 ng/ml on day 1 independently predicted bacterial sepsis (odds ratio, 8.6; 95% confidence interval, 2.53-29.3; P = 0.0006). PCT concentrations were not significantly correlated with hospital mortality. Despite limited specificity in critically ill immunocompromised patients, PCT concentrations may help to rule out bacterial infection.

Open source deformable image registration system for treatment planning and recurrence CT scans : Validation in the head and neck region.

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Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Rønn; Bertelsen, Anders; Johansen, Jørgen; Grau, Cai; Eriksen, Jesper Grau

2016-08-01

Clinical application of deformable registration (DIR) of medical images remains limited due to sparse validation of DIR methods in specific situations, e. g. in case of cancer recurrences. In this study the accuracy of DIR for registration of planning CT (pCT) and recurrence CT (rCT) images of head and neck squamous cell carcinoma (HNSCC) patients was evaluated. Twenty patients treated with definitive IMRT for HNSCC in 2010-2012 were included. For each patient, a pCT and an rCT scan were used. Median interval between the scans was 8.5 months. One observer manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. pCT and rCT images were deformably registered using the open source software elastix. Mean surface distance (MSD) and Dice similarity coefficient (DSC) between contours were used for validation of DIR. A measure for delineation uncertainty was estimated by assessing MSD from the re-delineations of the same ROI on pCT. DIR and manual contouring uncertainties were correlated with tissue volume and rigidity. MSD varied 1-3 mm for different ROIs for DIR and 1-1.5 mm for re-delineated ROIs performed on pCT. DSC for DIR varied between 0.58 and 0.79 for soft tissues and was 0.79 or higher for bony structures, and correlated with the volumes of ROIs (r = 0.5, p elastix in HNSCC on planning and recurrence CT scans is feasible; an uncertainty of the method is close to the voxel size length of the planning CT images.

Migrainous aura as stroke-mimic: The role of perfusion-computed tomography.

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Ridolfi, Mariana; Granato, Antonio; Polverino, Paola; Furlanis, Giovanni; Ukmar, Maja; Zorzenon, Irene; Manganotti, Paolo

2018-03-01

The acute-onset of migrainuos aura (MA) can be erroneously diagnosed in Emergency Department (ED) as acute stroke (AS) and it can be classified as "stroke mimic" (SM). Perfusion computer tomography (PCT) may be useful to improve detection of infarcts. The aim of the study was to investigate the role in ED of PCT in improving diagnosis of migrainous aura. Data were compared with the well-defined perfusion patterns in patients with acute ischemic stroke. A standardized Stroke Protocol was planned. The protocol consisted in centralizing in ED all the patients with acute-onset of neurological symptoms compatible with cerebrovascular disease and in performing a general and neurological examination, hematological tests, brain non-contrast computed tomography (NCCT), CT angiography (CTA) of the supra-aortic and intracranial arteries and cerebral PCT. Patients with diagnosis of definite or probable acute stroke were hospitalized in Stroke Unit (SU). A six-months retrospective analysis of all the patients included in the Stroke Protocol and discharged from ED or from SU with a diagnosis of migraine with aura was performed. 172 patients were included in the Stroke Protocol and 6 patients were enrolled. NCCT, CTA and PCT were performed after 60-90 min from symptoms onset and revealed normal perfusion. Intravenous thrombolysis was performed only in one patient. Patients with acute-onset of neurological symptoms, who have rapid progressive improvement of symptoms, normal neuroimaging, in particular PCT, and preceding episodes of migraine with aura, may be considered as suffering from MA. In these cases, even if thrombolysis is safe, clinicians may defer a prompt aggressive treatment. Copyright © 2018 Elsevier B.V. All rights reserved.

Porphyria Cutanea Tarda in a Patient with End-Stage Renal Disease: A Case of Successful Treatment with Deferoxamine and Ferric Carboxymaltose

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Natacha Rodrigues

2017-01-01

Full Text Available Porphyria cutanea tarda (PCT is a rare disease, with a strong association with hepatitis C virus. PCT is particularly problematic in end-stage renal disease patients as they have no renal excretion of porphyrins and these are poorly dialyzed. Also, conventional treatment of PCT is compromised in these patients as hydroxychloroquine is contraindicated, phlebotomies with the stipulated frequency are poorly tolerated in already anaemia-prone patients, and iron-chelating agents are less efficient in removing iron and contribute to worsening anaemia. The authors report a patient on haemodialysis, with hepatitis C infection, that is diagnosed with PCT. Despite the good clinical results with deferoxamine, she became dependent on blood transfusions because of her ferropenic state. Every time oxide iron was started, the patient developed clinical features of the disease, resolving after the suspension of the drug. A decision was made to start the patient on ferric carboxymaltose, which was well tolerated without disease symptoms and need of further blood transfusions. This case suggests that deferoxamine is efficient in treatment of porphyria cutanea tarda. Also, ferric carboxymaltose may be a valuable option for refractory anaemia in patients with this disease and end-stage renal disease, as it seems to provide iron without clinical relapse of the disease.

The mechanisms of dispersion strengthening and fracture in Al-based XD(tm) alloys, part 1

Science.gov (United States)

Aikin, R. M., Jr.

1990-01-01

The influence of reinforcement size, volume fraction, and matrix deformation behavior on room and elevated temperature strength; the fracture toughness; and the fatigue crack growth rate of metal matrix composites of Al-4(pct)Cu-1.5(pct)Mg with TiB2 were examined. The influence of reinforcement volume fraction was also examined for pure aluminum with TiB2. Higher TiB2 volume fractions increased the tensile yield strength at both room and elevated temperatures, and reduced the elongation to fracture. Tensile tests also indicate that small particles provided a greater increase in strength for a given volume fraction than larger particles, whereas elongation to fracture appeared to be insensitive to reinforcement size. Interparticle spacing appears to be the factor that controls the strength of these alloys, with the exact nature of the dependence relying on the nature of dislocation slip in the matrix (planar vs. diffuse). The isothermal aging response of the precipitation strengthened Al-4(pct)Cu-1.5(pct)Mg alloys was not accelerated by the presence of TiB2. Cold work prior to artificial aging created additional geometrically necessary dislocations which serve as heterogeneous nucleation sites leading to accelerated aging, a finer precipitate size, and an increase in the strength of the alloy.

Effect of decreased hot-rolling reduction treatment on fracture toughness of low-alloy structural steels

Science.gov (United States)

Tomita, Yoshiyuki

1990-09-01

Commercial low-alloy structural steels, 0.45 pct C (AISI 1045 grade), 0.40 pct C-Cr-Mo (AISI 4140 grade), and 0.40 pct C-Ni-Cr-Mo (AISI 4340 grade), have been studied to determine the effect of the decreased hot-rolling reduction treatment (DHRRT) from 98 to 80 pct on fracture toughness of quenched and highly tempered low-alloy structural steels. The significant conclusions are as follows: (1) the sulfide inclusions were modified through the DHRRT from a stringer (mean aspect ratio: 16.5 to 17.6) to an ellipse (mean aspect ratio: 3.8 to 4.5), independent of the steels studied; (2) the DHRRT significantly improved J Ic in the long-transverse and shorttransverse orientations, independent of the steels studied; and (3) the shelf energy in the Charpy V-notch impact test is also greatly improved by the DHRRT, independent of testing orientation and steels studied; however, (4) the ductile-to-brittle transition temperature was only slightly affected by the DHRRT. The beneficial effect on the J Ic is briefly discussed in terms of a crack extension model involving the formation of voids at the inclusion sites and their growth and eventual linking up through the rupture of the intervening ligaments by local shear.

Copper-Sulfate Pentahydrate as a Product of the Waste Sulfuric Acid Solution Treatment

Science.gov (United States)

Marković, Radmila; Stevanović, Jasmina; Avramović, Ljiljana; Nedeljković, Dragutin; Jugović, Branimir; Stajić-Trošić, Jasna; Gvozdenović, Milica

2012-12-01

The aim of this study is synthesis of copper-sulfate pentahydrate from the waste sulfuric acid solution-mother liquor generated during the regeneration process of copper bleed solution. Copper is removed from the mother liquor solution in the process of the electrolytic treatment using the insoluble lead anodes alloyed with 6 mass pct of antimony on the industrial-scale equipment. As the result of the decopperization process, copper is removed in the form of the cathode sludge and is precipitated at the bottom of the electrolytic cell. By this procedure, the content of copper could be reduced to the 20 mass pct of the initial value. Chemical characterization of the sludge has shown that it contains about 90 mass pct of copper. During the decopperization process, the very strong poison, arsine, can be formed, and the process is in that case terminated. The copper leaching degree of 82 mass pct is obtained using H2SO4 aqueous solution with the oxygen addition during the cathode sludge chemical treatment at 80 °C ± 5 °C. Obtained copper salt satisfies the requirements of the Serbian Standard for Pesticide, SRPS H.P1. 058. Therefore, the treatment of waste sulfuric acid solutions is of great economic and environmental interest.

Differences of serum procalcitonin levels between bacterial infection and flare in systemic lupus erythematosus patients

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Patrick, J.; Marpaung, B.; Ginting, Y.

2018-03-01

Differentiate bacterial infections from flare in SLE patients is difficult to do because clinical symptoms of infection is similar to flare. SLE patients with infection require antibiotic therapy with decreased doses of immunosuppressant while in flare diseases require increased immunosuppressant. Procalcitonin (PCT), a biological marker, increased in serum patients with bacterial infections and expected to be a solution of problem. The aim of this study was to examine the function of PCT serum as marker to differentiate bacterial infection and flare in SLE patients. This cross-sectional study was conducted in Adam Malik Hospital from January-July 2017. We examined 80 patients SLE flare (MEX-SLEDAI>5), screen PCT and culture according to focal infection. Data were statistically analyzed. 80 SLE patients divided into 2 groups: bacterial infection group (31 patients) and non-infection/flare group (49 patients). Median PCT levels of bacterial infection group was 1.66 (0.04-8.45)ng/ml while flare group was 0.12 (0.02-0.81)ng/ml. There was significant difference of serum Procalcitonin level between bacterial infection and flare group in SLE patients (p=0.001). Procalcitonin serum levels can be used as a biomarker to differentiate bacterial infections and flare in SLE patients.

Retinal Nerve Fiber Layer and Peripapillary Choroidal Thicknesses in Non-Glaucomatous Unilateral Optic Atrophy Compared with Unilateral Advanced Pseudoexfoliative Glaucoma.

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Kucukevcilioglu, Murat; Ayyildiz, Onder; Aykas, Seckin; Gokce, Gokcen; Koylu, Mehmet Talay; Ozgonul, Cem; Ozge, Gokhan; Mumcuoglu, Tarkan; Yumusak, Erhan

2017-02-01

To investigate retinal nerve fiber layer thickness (RNFL-T) and peripapillary choroidal thickness (PC-T) in non-glaucomatous optic atrophy (OA) patients in comparison with unaffected and control eyes, furthermore, to compare thickness profiles with unilateral pseudoexfoliative advanced glaucoma. Thirty-three eyes with OA (Group A), 33 unaffected fellow eyes (Group B), 25 right eyes of 25 control subjects (Group C), and 15 eyes with advanced glaucoma (Group D) were enrolled. RNFL-T was measured in six regions by spectral-domain optical coherence tomography. Enhanced depth imaging optical coherence tomography was obtained to evaluate PC-T in corresponding regions. RNFL-T was significantly lower in Group A than in Groups B and C globally and at all peripapillary regions (all p temporal > nasal > inferior) profiles were almost identical to that in unaffected fellow eyes and control eyes. However, Group D showed different patterns with less regional differences in RNFL-T, and the greatest value of PC-T in nasal quadrant. Besides retinal nerve fiber layer thinning, non-glaucomatous OA is associated with choroidal thinning. The RNFL-T and PC-T profiles in advanced glaucoma eyes differed from the common patterns seen among OA eyes, unaffected fellow eyes, and control eyes.

Urinary metabolic profiling of asymptomatic acute intermittent porphyria using a rule-mining-based algorithm.

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Luck, Margaux; Schmitt, Caroline; Talbi, Neila; Gouya, Laurent; Caradeuc, Cédric; Puy, Hervé; Bertho, Gildas; Pallet, Nicolas

2018-01-01

Metabolomic profiling combines Nuclear Magnetic Resonance spectroscopy with supervised statistical analysis that might allow to better understanding the mechanisms of a disease. In this study, the urinary metabolic profiling of individuals with porphyrias was performed to predict different types of disease, and to propose new pathophysiological hypotheses. Urine 1 H-NMR spectra of 73 patients with asymptomatic acute intermittent porphyria (aAIP) and familial or sporadic porphyria cutanea tarda (f/sPCT) were compared using a supervised rule-mining algorithm. NMR spectrum buckets bins, corresponding to rules, were extracted and a logistic regression was trained. Our rule-mining algorithm generated results were consistent with those obtained using partial least square discriminant analysis (PLS-DA) and the predictive performance of the model was significant. Buckets that were identified by the algorithm corresponded to metabolites involved in glycolysis and energy-conversion pathways, notably acetate, citrate, and pyruvate, which were found in higher concentrations in the urines of aAIP compared with PCT patients. Metabolic profiling did not discriminate sPCT from fPCT patients. These results suggest that metabolic reprogramming occurs in aAIP individuals, even in the absence of overt symptoms, and supports the relationship that occur between heme synthesis and mitochondrial energetic metabolism.

The Effect of Nb Addition on the Microstructure and the High-Temperature Strength of Fe3Al Aluminide

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Kratochvíl, Petr; Švec, Martin; Král, Robert; Veselý, Jozef; Lukáč, Pavel; Vlasák, Tomáš

2018-02-01

The microstructural and high-temperature mechanical properties of Fe-26Al-xNb (x = 3 and 5 at. pct) are compared. The alloys were investigated "as cast" and after hot rolling at 1473 K (1200 °C). Scanning electron microscopes equipped with EDS and EBSD were used for the microstructure and phase identification. The addition of 3 at. pct of Nb into the Fe3Al matrix leads to the formation of C14 λ—Laves phase (Fe,Al)2Nb (LP) particles spread in the Fe3Al matrix, while an eutectic with thin lamellae of LP C14 λ—Laves phase (Fe,Al)2Nb and matrix is also formed in the iron aluminide with 5 at. pct of Nb. The presence of incoherent precipitates is connected with the enhancement of the high-temperature strength and creep resistance.

Hydrogen isotope effect on storage behavior of U{sub 2}Ti and UZr{sub 2.3}

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Jat, Ram Avtar; Sawant, S.G.; Rajan, M.B.; Dhanuskar, J.R. [Product Development Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Kaity, Santu [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Parida, S.C., E-mail: sureshp@barc.gov.in [Product Development Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

2013-11-15

U{sub 2}Ti and UZr{sub 2.3} alloys were prepared by arc melting method, vacuum annealed and characterized by XRD, SEM and EDX methods. Hydrogen isotope effect on the storage behavior of these alloys were studied by measuring the hydrogen/deuterium desorption pressure–composition–temperature (PCT) profiles in the temperature range of 573–678 K using a Sievert’s type volumetric apparatus. It was observed that, in the temperature and pressure range of investigation, all the isotherms show a single desorption plateau. The PCT data reveals that both U{sub 2}Ti and UZr{sub 2.3} alloys had normal isotope effects on hydrogen/deuterium desorption at all experimental temperatures. Thermodynamic parameters for dehydrogenation and dedeuteration reactions of the corresponding hydrides and deuterides of the above alloys were deduced from the PCT data.

Deoxyglucose method for the estimation of local myocardial glucose metabolism with positron computed tomography

International Nuclear Information System (INIS)

Ratib, O.; Phelps, M.E.; Huang, S.C.; Henze, E.; Selin, C.E.; Schelbert, H.R.

1981-01-01

The deoxyglucose method originally developed for measurements of the local cerebral metabolic rate for glucose has been investigated in terms of its application to studies of the heart with positron computed tomography (PCT) and FDG. Studies were performed in dogs to measure the tissue kinetics of FDG with PCT and by direct arterial-venous sampling. The operational equation developed in our laboratory as an extension of the Sokoloff model was used to analyze the data. The FDG method accurately predicted the true MMRGlc even when the glucose metabolic rate was normal but myocardial blood flow (MBF) was elevated 5 times the control value or when metabolism was reduced to 10% of normal and MBF increased 5 times normal. Improvements in PCT resolution are required to improve the accuracy of the estimates of the rate constants and the MMRGlc

Procalcitonin as a diagnostic and prognostic marker in diabetic foot infection. A current literature review.

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Velissaris, Dimitrios; Pantzaris, Nikolaos-Dimitrios; Platanaki, Christina; Antonopoulou, Nikolina; Gogos, Charalampos

2018-03-01

Diabetic foot ulcers (DFUs) are a very common cause of mortality and morbidity. The distinction between infected and non-infected DFU remains a very challenging task for clinicians in everyday practice. Even when infection is documented, the spectrum of diabetic foot infection is wide, ranging from cellulitis and soft tissue infection to osteomyelitis. Procalcitonin (PCT), a well-established sepsis biomarker, has been used in the diagnosis of several infections including osteomyelitis in patients with diabetes mellitus. This review gathers and presents all the relevant data, up until now, regarding the use of PCT as an assessment tool in diabetic patients with foot infection. Current evidence suggests that PCT levels could aid clinicians in distinguishing infected from non-infected DFUs as well as in the distinction between soft tissue infection and bone involvement, but further and larger studies are warranted to confirm these findings.

Effect of grain-boundary crystallization on the high-temperature strength of silicon nitride

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Pierce, L. A.; Mieskowski, D. M.; Sanders, W. A.

1986-01-01

Si3N4 specimens having the composition 88.7 wt pct Si3N4-4.9 wt pct SiO2-6.4 wt pct Y2O3 were sintered at 2140 C under 25 atm N2 for 1 h and then subjected to a 5 h anneal at 1500 C. Crystallization of an amorphous grain-boundary phase resulted in the formation of Y2Si2O7. The short-time 1370 C strength of this material was compared with that of material of the same composition having no annealing treatment. No change in strength was noted. This is attributed to the refractory nature of the yttrium-rich grain-boundary phase (apparently identical in both glassy and crystalline phases) and the subsequent domination of the failure process by common processing flaws.

The Role of Control in Entrepreneurial Growth: An alternative explanation

DEFF Research Database (Denmark)

Neergaard, Helle; Jones, Sally; Ottsen, Christina Lundsgaard

their implications for concrete behaviour. Methodology: We apply a critical realist ontology to develop a research framework for understanding the role of risk, control and self-efficacy in determining entrepreneurial growth. We will collect data through an online questionnaire, including both men and women from...... and boys are socialized in the family. Contribution: We develop a research framework for testing propositions concerning the role of power-control in the family and the spillover effects that PCT has on entrepreneurial growth. We extend PCT into the entrepreneurship domain and offer new insights...... as they are viewed as more vulnerable than boys. Given that PCT deals with how risk-taking/adverse behaviour originates, it may have an application value in entrepreneurship. The gender gap in risk-taking has been addressed from various perspectives in the past 30 years, however, little effort has been made...

Phase Identification and Dielectric Properties of Pb0.94 Ca0.06 TiO3 Ceramics

International Nuclear Information System (INIS)

Khin Thida; Tin Tin Aye; Aye Aye Phyu; Moe Moe Myint; Ko Ko Kyaw Soe

2008-03-01

The ferroelectric materials of Ca (6 mol %) doped PbTiO3 (abbreviated to PCT6) ceamics were prepared by using conventional solid solution method. Phase assignment is identified by XRD technique. The change in capacitance, the variation of dielectric constant and dielectric loss as a function of applied frequency modes (1 kHz-10 kHz)at zero bias voltage of PCT6 ceramics by using Cu and Ag electrodes were investigated.

Height-Error Analysis for the FAA-Air Force Replacement Radar Program (FARR)

Science.gov (United States)

1991-08-01

7719 Figure 1-7 CLIMATOLOGY ERRORS BY MONWTH PERCENT FREQUENCY TABLE OF ERROR BY MONTH ERROR MONTH Col Pc IJAl IFEB )MA IA R IAY JJ’N IJUL JAUG (SEP...MONTH Col Pct IJAN IFEB IMPJ JAPR 1 MM IJUN IJUL JAUG ISEP J--T IN~ IDEC I Total ----- -- - - --------------------------.. . -.. 4...MONTH ERROR MONTH Col Pct IJAN IFEB IM4AR IAPR IMAY jJum IJU JAUG ISEP JOCT IN JDEC I Total . .- 4

Summary of Synoptic Meteorological Observations. North American Coastal Marine Areas - Revised. Atlantic and Gulf Coasts. Volume I. Revised. Area 1 - Belle Isle Strait. Area 2 - Osv Bravo. Area 3 - NE Newfoundland Coast. Area 4 - SE Newfoundland Coast. Area 5 - Placentia Bay South. Area 6 - Cabot Strait. Area 7 - Anticosti Island

Science.gov (United States)

1975-05-01

H71 JUNE T4BU 1? IKEA 0006 CABPT STKAIT »6.7N 58.in PCT FKfO Of AID TEMPERATURE (DE6 Fl ANn THE OCCURRENCE OF FOB IWITHGUT PRECIPITATION...OVE»-iLL) m7*-1970 JULY T«»LE IT IKEA 0006 CilOT STIUIT 46.6N Sa.lW PCT f»P0 0» Mi TEMPE»»TU»E (D6G Fl »MB THE

On the application of positron computed tomography to neuro-psychiatric diseases

International Nuclear Information System (INIS)

Kodama, Kazuhiro; Tateno, Yukio; Shishido, Fumio.

1983-01-01

Reports on the application of positron CT (PCT) to neuropsychiatric diseases were introduced, and this method was compared with conventional methods for the measurement of cerebral circulation/metabolism and with XCT. Currently, PCT is used in physiological study, the study of the intracranial distribution of chlorpromazine and measurements of the cerebral flow rate, glucose consumption and oxygen consumption in patients with Hungtinton's chorea, dimentia, epilepsy and schizophrenia. Their new data are available. (Chiba, N.)

Development of emission computed tomography in Japan

International Nuclear Information System (INIS)

Tanaka, E.

1984-01-01

Two positron emission computed tomography (PCT) devices developed in Japan are described. One is for head and the other for wholebody. The devices show fairly quantitative images with slight modifications of the existing algorithms because they were developed based on filtered back-projection. The PCT device seems to be better than the single photon emission computed tomography (SPECT) since it provides adequade compensation for photon attenuation in patients. (M.A.C.) [pt

Avaliação do programa de controle da tuberculose em cenário Amazônico: desafios em Coari Evaluation of a tuberculosis control program in an Amazonian scenario: challenges in Coari

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Nicolás Esteban Castro Heufemann

2013-03-01

Full Text Available Pesquisa avaliativa, tipo estudo de caso, do contexto e grau de implantação do Programa de Controle da Tuberculose (PCT no município de Coari, Amazonas, 2001-2008. As técnicas de pesquisa conjugaram abordagens quantitativa e qualitativa, com uso de modelo lógico e matriz de julgamento. O componente quantitativo utilizou dados do Sistema de Informação de Agravos de Notificação e dados populacionais do Departamento de Informática do Sistema Único de Saúde. As variáveis foram, idade, sexo, forma clínica, procedência, tipo de entrada, meios diagnósticos e situação de encerramento. Para a população foram feitos cálculos de interpolação geométrica, por faixa etária, sexo e procedência (urbana e rural. O componente qualitativo combinou técnicas e fontes: pesquisa documental; observação e entrevista. O modelo lógico propiciou o entendimento da estrutura, processo e resultado do PCT; e a matriz de julgamento permitiu identificar o grau de implantação. A taxa média de incidência da tuberculose na área urbana foi 27 casos por 100.000 habitantes e de 9,4 por 100.000 habitantes na área rural, com razão masculino/feminino de 1,6. A avaliação do contexto externo, vigilância epidemiológica e operacionalização do PCT mostrou grau de implantação intermediário. No contexto organizacional, estrutura física das Unidades Saúde, recursos humanos e efetividade, o resultado foi incipiente. No geral, o grau de implantação foi intermediário. A flutuação nas notificações e taxas anuais de incidência, associada ao não cumprimento das metas do PCT, à desarticulação entre o PCT e o restante da atenção básica e à não interiorização da assistência indicam sérias dificuldades na operacionalização das ações de controle da tuberculose.This is an evaluative research, a type of study case of the context and degree of implementation of the Tuberculosis Control Program (PCT in the city of Coari, State of Amazonas

PROFESSIONAL SPECIFICITY OF CONCEPTUAL THINKING

Directory of Open Access Journals (Sweden)

S. A. Gilmanov

2017-01-01

Full Text Available Introduction. Most studies of psychologists and teachers in the phenomenon of conceptual thinking and ways of its formation are considered to be rather controversial and questionable. However, the research results were limited to the phenomenon of conceptual thinking and are therefore not representative for its implementation during the process of vocational training at the higher school. There is still considerable uncertainty with regard to the approaches to the problem of conceptual thinking in the humanities, including pedagogics and psychology. Furthermore, previous studies have not dealt with the objectives of conceptual thinking formation.The aims of the article are: to justify the use of the term “professional conceptualization of thinking” (PCT in theory and practice; to describe the prospects of the development of PCT in the training process.Methodology and research methods. The methodological base of the research involves the Russian psychological and pedagogical science approaches to the consideration of conceptual thinking as a higher mental function, a systematized and summarized form of cognitive reflection of notions and relations of reality. The experimental work was carried out using the method of observation, interviews, and tests. Quantitative and qualitative analysis of the data was conducted. The process of formation of PCT is described through the theory of stage-by-stage systematic development of mental acts.Results and scientific novelty. The concept “professional conceptualization of thinking” (PCT, a new one for psychological-pedagogical science, is suggested. The PCT levels are identified: ordinary, formal, substantial, system, and holistic. The objectives proposed for the development of the PCT levels in the process of professional education consist in the organization of consecutive transition from conscious mastering of a terminological framework to its use in the performance of educational tasks; from

Efficacy and Safety of Procalcitonin-Guided Antibiotic Therapy in Lower Respiratory Tract Infections

Directory of Open Access Journals (Sweden)

Werner C. Albrich

2013-01-01

Full Text Available Background: In 14 randomized controlled studies to date, a procalcitonin (PCT-based algorithm has been proven to markedly reduce the use of antibiotics along with an unimpaired high safety and low complication rates in patients with lower respiratory tract infections (LRTIs. However, compliance with the algorithm and safety out of controlled study conditions has not yet been sufficiently investigated. Methods: We performed a prospective international multicenter observational post-study surveillance of consecutive adults with community-acquired LRTI in 14 centers (Switzerland (n = 10, France (n = 3 and the United States (n = 1. Results: Between September 2009 and November 2010, 1,759 patients were enrolled (median age 71; female sex 44.4%. 1,520 (86.4% patients had a final diagnosis of LRTI (community-acquired pneumonia (CAP, 53.7%; acute exacerbation of chronic obstructive pulmonary disease (AECOPD, 17.1%; and acute bronchitis, 14.4%. Compliance with the PCT-guided therapy (overall 68.2% was highest in patients with bronchitis (81.0% vs. AECOPD, 70.1%; CAP, 63.7%; p < 0.001, outpatients (86.1% vs. inpatients, 65.9%; p < 0.001 and algorithm-experienced centers (82.5% vs. algorithm-naive, 60.1%; p < 0.001 and showed significant geographical differences. The initial decision about the antibiotic therapy was based on PCT value in 72.4%. In another 8.6% of patients, antibiotics were administered despite low PCT values but according to predefined criteria. Thus, the algorithm was followed in 81.0% of patients. In a multivariable Cox hazard ratio model, longer antibiotic therapy duration was associated with algorithm-non-compliance, country, hospitalization, CAP vs. bronchitis, renal failure and algorithm-naïvety of the study center. In a multivariable logistic regression complications (death, empyema, ICU treatment, mechanical ventilation, relapse, and antibiotic-associated side effects were significantly associated with increasing CURB65-Score, CAP

TH-AB-209-05: Validating Hemoglobin Saturation and Dissolved Oxygen in Tumors Using Photoacoustic Computed Tomographic Spectroscopic Imaging

Energy Technology Data Exchange (ETDEWEB)

Burnett, J; Sick, J; Liu, B [Purdue University, West Lafayette, IN (United States); Cao, N [University of Washington Medical Center, Seattle, WA (United States); Nakshatri, H; Mendonca, M [Indiana University - Purdue University Indianapolis, Indianapolis, IN (United States); Stantz, K [Purdue University, West Lafayette, IN (United States); Indiana University - Purdue University Indianapolis, Indianapolis, IN (United States)

2016-06-15

Purpose: Photoacoustic computed tomographic spectroscopy (PCT-S) provides intra-tumor measurements of oxygenation with high spatial resolution (0.2mm) and temporal fidelity (1–2 minutes) without the need for exogenous agents or ionizing radiation, thus providing a unique in vivo assay to measure SaO{sub 2} and investigate acute and chronic forms of hypoxia. The goal of this study is to validate in vivo SaO{sub 2} levels within tail artery of mice and the relationship between SaO{sub 2} and pO{sub 2} within subcutaneous breast tumors using PCT-S imaging, pulse oximetry and an OxyLite probe. Methods: A closed circuit phantom was fabricated to control blood oxygenation levels, where SaO{sub 2} was measured using a co-oximeter and pO{sub 2} using an Oxylite probe. Next, SaO{sub 2} levels within the tail arteries of mice (n=3) were measured using PCT-S and pulse oximetry while breathing high-to-low oxygen levels (6-cycles). Finally, PCT-S was used to measure SaO{sub 2} levels in MCF-7, MCF-7-VEGF165, and MDA-MB-231 xenograft breast tumors and compared to Oxylite pO{sub 2} levels values. Results: SaO{sub 2} and pO{sub 2} data obtained from the calibration phantom was fit to Hill’s equation: aO{sub 2} levels between 88 and 52% demonstrated a linear relationship (r2=0.96) and a 3.2% uncertainty between PCT-S values relative to pulse oximetry. Scatter plots of localized PCT-S measured SaO2 and Oxylite pO{sub 2} levels in MCF-7/MCF-7-VEGF165 and MDA-MD-231 breast tumors were fit to Hill’s equation: P50=17.2 and 20.7mmHg, and n=1.76 and 1.63. These results are consistent with sigmoidal form of Hill’s equation, where the lower P{sub 50} value is indicative of an acidic tumor microenvironment. Conclusion: The results demonstrate photoacoustic imaging can be used to measure SaO{sub 2} cycling and intra-tumor oxygenation, and provides a powerful in vivo assay to investigate the role of hypoxia in radiation, anti-angiogenic, and immunotherapies.

SU-C-18A-05: Registration Accuracy of MR-Based Images to On-Board Megavoltage Cone-Beam CT for Brain Patient Setup

International Nuclear Information System (INIS)

Pinnaduwage, D S; Chen, J; Descovich, M; Pouliot, J; Hwang, Ken-Ping

2014-01-01

Purpose: To quantify the difference in isocenter shifts when co-registering MR and MR-based pseudo CTs (pCT) with on-board megavoltage conebeam CT (CBCT) images. Methods: Fast Spoiled Gradient Echo MRs were used to generate pCTs (research version of Advantage Sim MD™, GE Healthcare) for ten patients who had prior brain radiotherapy. The planning CT (rCT) for each was co-registered with the MR, and the plan isocenter and two other reference points were transferred to the MR and pCT. CBCT images (with the machine isocenter) from a single treatment day were coregistered with the 3 test images (MR, pCT and rCT), by two observers and by an automated registration algorithm. The reference points were used to calculate patient shifts and rotations from the registrations. The shifts calculated from the test image registrations were compared to each other and to the shifts performed by the therapists who treated the patients on that day. Results: The average difference in absolute value between the isocenter shifts from the MR-, pCT- and rCT-CBCT registrations, and the therapist shifts, were 2.02, 3.01 and 0.89 mm (craniocaudal), 1.14, 1.34 and 0.46 mm (lateral), and 1.37, 3.43 and 1.43 mm (vertical), respectively. The MR- and pCT-CBCT registrations differed by 1.99, and 2.53 mm (craniocaudal), 1.36, and 1.37 mm (lateral), and 0.74 and 2.34 mm (vertical), respectively, from the average rCT-CBCT shifts. On average, differences of 2.39 (craniocaudal), 1.28 (lateral) and 2.84 mm (vertical) were seen between the MR and pCT shifts. Rotations relative to the CBCT coordinate system were on average <2° for the MR and rCT, and <6° for the pCT. Conclusion: In this study, FSPGR MR-CBCT registrations were more precise compared to the pCT-CBCT registrations. For improved accuracy, MR sequences that are optimal for bony anatomy visualization are necessary. GE healthcare has provided a research version of Advantage Sim MD to UCSF. No financial support was provided

Application of phase coherent transform to cloud clutter suppression

Energy Technology Data Exchange (ETDEWEB)

Ng, L.C. [Lawrence Livermore National Lab., CA (United States)

1994-11-15

This paper describes a tracking algorithm using frame-to-frame correlation with frequency domain clutter suppression. Clutter suppression was mechanized via a `Phase Coherent Transform` (PCT) approach. This approach was applied to explore the feasibility of tracking a post-boost rocket from a low earth orbit satellite with real cloud background data. Simulation results show that the PCT/correlation tracking algorithm can perform satisfactorily at signal-to-clutter ratio (SCR) as low as 5 or 7 dB.

Research on Diamantane and other High Density Hydrocarbon Fuels.

Science.gov (United States)

1979-10-01

CH2 C 2 solvent ,= : 5.21 6.87 exo- OCPD . 18.61 Isomers of THTriCPD endo ,exo ,endo-THTri CPD tI 156 238 I.. 5,939R NO METHOD RT AREA AREA % 5.21 761680...0743122-1 HEATED OCPD 5300 E.JANOSKI 773417Cut Atmos. TFJUP.. 11T. G1S. VOL- MLS. SP.GR.GO/60 F WT.PCT VOL.PCT. h:)q n n-n n n 473 900 17.0 18.7

Positron emission tomography of the heart

International Nuclear Information System (INIS)

Schelbert, H.R.; Phelps, M.E.; Kuhl, D.E.

1979-01-01

Positron emission computed tomography (PCT) represents an important new tool for the noninvasive evaluation and, more importantly, quantification of myocardial performance. Most currently available techniques permit assessment of only one aspect of cardiac function, i.e., myocardial perfusion by gamma scintillation camera imaging with Thallium-201 or left ventricular function by echocardiography or radionuclide angiocardiography. With PCT it may become possible to study all three major segments of myocardial performance, i.e., regional blood flow, mechanical function and, most importantly, myocardial metabolism. Each of these segments can either be evaluated separately or in combination. This report briefly describes the principles and technological advantages of the imaging device, reviews currently available radioactive tracers and how they can be employed for the assessment of flow, function and metabolism; and, lastly, discusses possible applications of PCT for the study of cardiac physiology or its potential role in the diagnosis of cardiac disease

Positron emission tomography of the heart

Energy Technology Data Exchange (ETDEWEB)

Schelbert, H.R.; Phelps, M.E.; Kuhl, D.E.

1979-01-01

Positron emission computed tomography (PCT) represents an important new tool for the noninvasive evaluation and, more importantly, quantification of myocardial performance. Most currently available techniques permit assessment of only one aspect of cardiac function, i.e., myocardial perfusion by gamma scintillation camera imaging with Thallium-201 or left ventricular function by echocardiography or radionuclide angiocardiography. With PCT it may become possible to study all three major segments of myocardial performance, i.e., regional blood flow, mechanical function and, most importantly, myocardial metabolism. Each of these segments can either be evaluated separately or in combination. This report briefly describes the principles and technological advantages of the imaging device, reviews currently available radioactive tracers and how they can be employed for the assessment of flow, function and metabolism; and, lastly, discusses possible applications of PCT for the study of cardiac physiology or its potential role in the diagnosis of cardiac disease.

A patch-based pseudo-CT approach for MRI-only radiotherapy in the pelvis

DEFF Research Database (Denmark)

Andreasen, Daniel; Van Leemput, Koen; Edmund, Jens M.

2016-01-01

. The authors benchmark the method against a baseline pCT strategy where all voxels inside the body contour are assigned a water-equivalent bulk density. Furthermore, the authors implement a parallelized approximate patch search strategy to speed up the pCT generation time to a more clinically relevant level....... The data consisted of CT and T 1-weighted MRI scans of 10 prostate patients. pCTs were generated using an approximate patch search algorithm in a leave-one-out fashion and compared with the CT using frequently described metrics such as the voxel-wise mean absolute error (MAEvox) and the deviation in water...... showed that a patch-based method based on affine registrations and T 1-weighted MRI could generate accurate pCTs of the pelvis. The main source of differences between pCT and CT was positional changes of air pockets and body outline....

Effect of W Contents on Martensitic Transformation and Shape Memory Effect in Co-Al-W Alloys

Science.gov (United States)

Yang, X.; Qian, B. N.; Peng, H. B.; Wu, B. J.; Wen, Y. H.

2018-04-01

To clarify the effect of W contents on the shape memory effect (SME) in the Co-Al alloys and its influencing mechanism, the SME, martensitic transformation, and deformation behavior were studied in the Co-7Al-xW ( x = 0, 4, 6, 9 wt pct) alloys. The results showed that the additions of W all deteriorated the SME in Co-7Al alloy when deformed at room temperature. However, when deformed in liquid nitrogen, the SME in Co-7Al alloy could be remarkably improved from 43 to 78 pct after the addition of 4 pct W, above which the SME decreased rapidly with the increase of W content although the yield strength of the parent phase rose due to the solution strengthening of W. The deterioration in SME induced by the excessive addition of W could be ascribed to its resulting significant drop of the start temperature of martensitic transformation.

Chemical Reactions in the Processing of Mosi2 + Carbon Compacts

Science.gov (United States)

Jacobson, Nathan S.; Lee, Kang N.; Maloy, Stuart A.; Heuer, Arthur H.

1993-01-01

Hot-pressing of MoSi2 powders with carbon at high temperatures reduces the siliceous grain boundary phase in the resultant compact. The chemical reactions in this process were examined using the Knudsen cell technique. A 2.3 wt pct oxygen MoSi2 powder and a 0.59 wt pct oxygen MoSi2 powder, both with additions of 2 wt pct carbon, were examined. The reduction of the siliceous grain boundary phase was examined at 1350 K and the resultant P(SiO)/P(CO) ratios interpreted in terms of the SiO(g) and CO(g) isobars on the Si-C-O predominance diagram. The MoSi2 + carbon mixtures were then heated at the hot-pressing temperature of 2100 K. Large weight losses were observed and could be correlated with the formation of a low-melting eutectic and the formation and vaporization of SiC.

Superplastic forming of rapid solidification processed Al-4Li-0.2Zr

International Nuclear Information System (INIS)

Meschter, P.J.; Lederich, R.J.; Sastry, S.M.L.

1987-01-01

Aluminum-4 wt pct lithium alloys are attractive as structural materials because they are 13 to 14 pct less dense and have 25 pct larger elastic moduli than high-strength 2XXX-and 7XXX-series aluminum alloys. These low-density alloys can be produced only by rapid solidification processing (RSP). Successful RSP of Al-4Li-0.2Zr, Al-4Li-1Mg-0.2Zr, and Al-4Li-1Cu-0.2Zr alloys with strengths similar to that of 7075-T76 has recently been demonstrated. Net-shaped processing techniques such as superplastic forming are capable of producing complex structural elements while minimizing usage of expensive material; thus, these techniques are particularly applicable to Al-Li alloys. The purpose of this study was to determine the conditions of strain rate and temperature under which RSP Al-4Li alloys could be superplastically formed

Reproducibility of Dynamic Computed Tomography Brain Perfusion Measurements in Patients with Significant Carotid Artery Stenosis

International Nuclear Information System (INIS)

Serafin, Z.; Kotarski, M.; Karolkiewicz, M.; Mindykowski, R.; Lasek, W.; Molski, S.; Gajdzinska, M.; Nowak-Nowacka, A.

2009-01-01

Background: Perfusion computed tomography (PCT) determination is a minimally invasive and widely available technique for brain blood flow assessment, but its application may be restricted by large variation of results. Purpose: To determine the intraobserver, interobserver, and inter examination variability of brain PCT absolute measurements in patients with significant carotid artery stenosis (CAS), and to evaluate the effect of the use of relative perfusion values on PCT reproducibility. Material and Methods: PCT imaging was completed in 61 patients before endarterectomy, and in 38 of these within 4 weeks after treatment. Cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), and peak enhancement intensity (PEI) were calculated with the maximum slope method. Inter examination variability was evaluated based on perfusion of hemisphere contralateral to the treated CAS, from repeated examinations. Interobserver and intraobserver variability were established for the untreated side, based on pretreatment examination. Results: Interobserver and intraobserver variability were highest for CBF measurement (28.8% and 32.5%, respectively), and inter examination variability was the highest for CBV (24.1%). Intraobserver and interobserver variability were higher for absolute perfusion values compared with their respective ratios for CBF and TTP. The only statistically significant difference between perfusion values measured by two observers was for CBF (mean 78.3 vs. 67.5 ml/100 g/min). The inter examination variability of TTP (12.1%) was significantly lower than the variability of other absolute perfusion measures, and the inter examination variability of ratios was significantly lower than absolute values for all the parameters. Conclusion: In longitudinal studies of patients with chronic cerebral ischemia, PCT ratios and either TTP or CBV are more suitable measures than absolute CBF values, because of their considerably lower inter- and intraobserver

Collateral circulation on perfusion-computed tomography-source images predicts the response to stroke intravenous thrombolysis.

Science.gov (United States)

Calleja, A I; Cortijo, E; García-Bermejo, P; Gómez, R D; Pérez-Fernández, S; Del Monte, J M; Muñoz, M F; Fernández-Herranz, R; Arenillas, J F

2013-05-01

Perfusion-computed tomography-source images (PCT-SI) may allow a dynamic assessment of leptomeningeal collateral arteries (LMC) filling and emptying in middle cerebral artery (MCA) ischaemic stroke. We described a regional LMC scale on PCT-SI and hypothesized that a higher collateral score would predict a better response to intravenous (iv) thrombolysis. We studied consecutive ischaemic stroke patients with an acute MCA occlusion documented by transcranial Doppler/transcranial color-coded duplex, treated with iv thrombolysis who underwent PCT prior to treatment. Readers evaluated PCT-SI in a blinded fashion to assess LMC within the hypoperfused MCA territory. LMC scored as follows: 0, absence of vessels; 1, collateral supply filling ≤ 50%; 2, between> 50% and < 100%; 3, equal or more prominent when compared with the unaffected hemisphere. The scale was divided into good (scores 2-3) vs. poor (scores 0-1) collaterals. The predetermined primary end-point was a good 3-month functional outcome, while early neurological recovery, transcranial duplex-assessed 24-h MCA recanalization, 24-h hypodensity volume and hemorrhagic transformation were considered secondary end-points. Fifty-four patients were included (55.5% women, median NIHSS 10), and 4-13-23-14 patients had LMC score (LMCs) of 0-1-2-3, respectively. The probability of a good long-term outcome augmented gradually with increasing LMCs: (0) 0%; (1) 15.4%; (2) 65.2%; (3) 64.3%, P = 0.004. Good-LMCs was independently associated with a good outcome [OR 21.02 (95% CI 2.23-197.75), P = 0.008]. Patients with good LMCs had better early neurological recovery (P = 0.001), smaller hypodensity volumes (P < 0.001) and a clear trend towards a higher recanalization rate. A higher degree of LMC assessed by PCT-SI predicts good response to iv thrombolysis in MCA ischaemic stroke patients. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

Numerical Simulation and Industrial Experimental Research on the Coherent Jet with "CH4 + N2" Mixed Fuel Gas

Science.gov (United States)

Hu, Shaoyan; Zhu, Rong; Dong, Kai; Liu, Runzao

2018-06-01

Coherent jet technology is widely used in the electric arc furnace (EAF) steelmaking process to deliver more energy and momentum into the molten steel bath. Meanwhile, the characteristics of a coherent jet using pure CH4 as the fuel gas have been well investigated in previous studies. To reduce the consumption of CH4, coherent jet technology using "CH4 + N2" mixed fuel gas instead of pure CH4 was proposed and studied in detail by numerical simulation in the present work. The Eddy Dissipation Concept model, which has detailed chemical kinetic mechanisms, was adopted to model the fuel gas combustion reactions. Experimental measurements were carried out to validate the accuracy of the computational model. The present study shows that the jet characteristics of the main oxygen improve along with the increase of the CH4 ratio in fuel gas and with the increase of the flow rate of fuel gas. When the CH4 ratio in the fuel gas is 25 pct, the fuel gas flow rate only has a limited influence on the jet characteristics, unlike the rest of the fuel gas compositions, because a high N2 proportion deteriorates the combustion performance and leads to severe incomplete combustion. Moreover, a false potential core phenomenon was observed and explained in the present study. Based on the average values, the jet length of a coherent jet with 75 pct CH4 can achieve 89.8 pct of that with 100 pct CH4. Finally, an industrial experiment was carried out on a commercial 100t EAF using coherent jet with 75 pct CH4, showing that the average CH4 consumption was reduced from 3.84 to 3.05 Nm3 t-1 under the premise of no obvious changes in the other production indexes.

SU-G-BRA-10: Marker Free Lung Tumor Motion Tracking by An Active Contour Model On Cone Beam CT Projections for Stereotactic Body Radiation Therapy of Lung Cancer

International Nuclear Information System (INIS)

Chao, M; Yuan, Y; Lo, Y; Wei, J

2016-01-01

Purpose: To develop a novel strategy to extract the lung tumor motion from cone beam CT (CBCT) projections by an active contour model with interpolated respiration learned from diaphragm motion. Methods: Tumor tracking on CBCT projections was accomplished with the templates derived from planning CT (pCT). There are three major steps in the proposed algorithm: 1) The pCT was modified to form two CT sets: a tumor removed pCT and a tumor only pCT, the respective digitally reconstructed radiographs DRRtr and DRRto following the same geometry of the CBCT projections were generated correspondingly. 2) The DRRtr was rigidly registered with the CBCT projections on the frame-by-frame basis. Difference images between CBCT projections and the registered DRRtr were generated where the tumor visibility was appreciably enhanced. 3) An active contour method was applied to track the tumor motion on the tumor enhanced projections with DRRto as templates to initialize the tumor tracking while the respiratory motion was compensated for by interpolating the diaphragm motion estimated by our novel constrained linear regression approach. CBCT and pCT from five patients undergoing stereotactic body radiotherapy were included in addition to scans from a Quasar phantom programmed with known motion. Manual tumor tracking was performed on CBCT projections and was compared to the automatic tracking to evaluate the algorithm accuracy. Results: The phantom study showed that the error between the automatic tracking and the ground truth was within 0.2mm. For the patients the discrepancy between the calculation and the manual tracking was between 1.4 and 2.2 mm depending on the location and shape of the lung tumor. Similar patterns were observed in the frequency domain. Conclusion: The new algorithm demonstrated the feasibility to track the lung tumor from noisy CBCT projections, providing a potential solution to better motion management for lung radiation therapy.

SU-G-BRA-10: Marker Free Lung Tumor Motion Tracking by An Active Contour Model On Cone Beam CT Projections for Stereotactic Body Radiation Therapy of Lung Cancer

Energy Technology Data Exchange (ETDEWEB)

Chao, M; Yuan, Y; Lo, Y [The Mount Sinai Medical Center, New York, NY (United States); Wei, J [City College of New York, New York, NY (United States)

2016-06-15

Purpose: To develop a novel strategy to extract the lung tumor motion from cone beam CT (CBCT) projections by an active contour model with interpolated respiration learned from diaphragm motion. Methods: Tumor tracking on CBCT projections was accomplished with the templates derived from planning CT (pCT). There are three major steps in the proposed algorithm: 1) The pCT was modified to form two CT sets: a tumor removed pCT and a tumor only pCT, the respective digitally reconstructed radiographs DRRtr and DRRto following the same geometry of the CBCT projections were generated correspondingly. 2) The DRRtr was rigidly registered with the CBCT projections on the frame-by-frame basis. Difference images between CBCT projections and the registered DRRtr were generated where the tumor visibility was appreciably enhanced. 3) An active contour method was applied to track the tumor motion on the tumor enhanced projections with DRRto as templates to initialize the tumor tracking while the respiratory motion was compensated for by interpolating the diaphragm motion estimated by our novel constrained linear regression approach. CBCT and pCT from five patients undergoing stereotactic body radiotherapy were included in addition to scans from a Quasar phantom programmed with known motion. Manual tumor tracking was performed on CBCT projections and was compared to the automatic tracking to evaluate the algorithm accuracy. Results: The phantom study showed that the error between the automatic tracking and the ground truth was within 0.2mm. For the patients the discrepancy between the calculation and the manual tracking was between 1.4 and 2.2 mm depending on the location and shape of the lung tumor. Similar patterns were observed in the frequency domain. Conclusion: The new algorithm demonstrated the feasibility to track the lung tumor from noisy CBCT projections, providing a potential solution to better motion management for lung radiation therapy.

SU-D-BRD-01: An Automated Physics Weekly Chart Checking System Supporting ARIA

Energy Technology Data Exchange (ETDEWEB)

Chang, X; Yang, D [Washington University in St Louis, St Louis, MO (United States)

2015-06-15

Purpose: A software tool was developed in this study to perform automatic weekly physics chart check on the patient data in ARIA. The tool accesses the electronic patient data directly from ARIA server and checks the accuracy of treatment deliveries, and generates reports which summarize the delivery history and highlight the errors. Methods: The tool has four modules. 1) The database interface is designed to directly access treatment delivery data from the ARIA database before reorganizing the data into the patient chart tree (PCT). 2) PCT is a core data structure designed to store and organize the data in logical hierarchies, and to be passed among functions. 3) The treatment data check module analyzes the organized data in PCT and stores the checking results into PCT. 4) Report generation module generates reports containing the treatment delivery summary, chart checking results and plots of daily treatment setup parameters (couch table positions, shifts of image guidance). The errors that are found by the tool are highlighted with colors. Results: The weekly check tool has been implemented in MATLAB and clinically tested at two major cancer centers. Javascript, cascading style sheets (CSS) and dynamic HTML were employed to create the user-interactive reports. It takes 0.06 second to search the delivery records of one beam with PCT and compare the delivery records with beam plan. The reports, saved in the HTML files on shared network folder, can be accessed by web browser on computers and mobile devices. Conclusion: The presented weekly check tool is useful to check the electronic patient treatment data in Varian ARIA system. It could be more efficient and reliable than the manually check by physicists. The work was partially supported by a research grant from Varian Medical System.

SU-D-BRD-01: An Automated Physics Weekly Chart Checking System Supporting ARIA

International Nuclear Information System (INIS)

Chang, X; Yang, D

2015-01-01

Purpose: A software tool was developed in this study to perform automatic weekly physics chart check on the patient data in ARIA. The tool accesses the electronic patient data directly from ARIA server and checks the accuracy of treatment deliveries, and generates reports which summarize the delivery history and highlight the errors. Methods: The tool has four modules. 1) The database interface is designed to directly access treatment delivery data from the ARIA database before reorganizing the data into the patient chart tree (PCT). 2) PCT is a core data structure designed to store and organize the data in logical hierarchies, and to be passed among functions. 3) The treatment data check module analyzes the organized data in PCT and stores the checking results into PCT. 4) Report generation module generates reports containing the treatment delivery summary, chart checking results and plots of daily treatment setup parameters (couch table positions, shifts of image guidance). The errors that are found by the tool are highlighted with colors. Results: The weekly check tool has been implemented in MATLAB and clinically tested at two major cancer centers. Javascript, cascading style sheets (CSS) and dynamic HTML were employed to create the user-interactive reports. It takes 0.06 second to search the delivery records of one beam with PCT and compare the delivery records with beam plan. The reports, saved in the HTML files on shared network folder, can be accessed by web browser on computers and mobile devices. Conclusion: The presented weekly check tool is useful to check the electronic patient treatment data in Varian ARIA system. It could be more efficient and reliable than the manually check by physicists. The work was partially supported by a research grant from Varian Medical System

Reproducibility of Dynamic Computed Tomography Brain Perfusion Measurements in Patients with Significant Carotid Artery Stenosis

Energy Technology Data Exchange (ETDEWEB)

Serafin, Z.; Kotarski, M.; Karolkiewicz, M.; Mindykowski, R.; Lasek, W.; Molski, S.; Gajdzinska, M.; Nowak-Nowacka, A. (Dept. of Radiology and Diagnostic Imaging, and Dept. of General and Vascular Surgery, Nicolaus Copernicus Univ., Collegium Medicum, Bydgoszcz (Poland))

2009-02-15

Background: Perfusion computed tomography (PCT) determination is a minimally invasive and widely available technique for brain blood flow assessment, but its application may be restricted by large variation of results. Purpose: To determine the intraobserver, interobserver, and inter examination variability of brain PCT absolute measurements in patients with significant carotid artery stenosis (CAS), and to evaluate the effect of the use of relative perfusion values on PCT reproducibility. Material and Methods: PCT imaging was completed in 61 patients before endarterectomy, and in 38 of these within 4 weeks after treatment. Cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), and peak enhancement intensity (PEI) were calculated with the maximum slope method. Inter examination variability was evaluated based on perfusion of hemisphere contralateral to the treated CAS, from repeated examinations. Interobserver and intraobserver variability were established for the untreated side, based on pretreatment examination. Results: Interobserver and intraobserver variability were highest for CBF measurement (28.8% and 32.5%, respectively), and inter examination variability was the highest for CBV (24.1%). Intraobserver and interobserver variability were higher for absolute perfusion values compared with their respective ratios for CBF and TTP. The only statistically significant difference between perfusion values measured by two observers was for CBF (mean 78.3 vs. 67.5 ml/100 g/min). The inter examination variability of TTP (12.1%) was significantly lower than the variability of other absolute perfusion measures, and the inter examination variability of ratios was significantly lower than absolute values for all the parameters. Conclusion: In longitudinal studies of patients with chronic cerebral ischemia, PCT ratios and either TTP or CBV are more suitable measures than absolute CBF values, because of their considerably lower inter- and intraobserver

Filtered backprojection proton CT reconstruction along most likely paths

Energy Technology Data Exchange (ETDEWEB)

Rit, Simon; Dedes, George; Freud, Nicolas; Sarrut, David; Letang, Jean Michel [Universite de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Universite Lyon 1, Centre Leon Berard, 69008 Lyon (France)

2013-03-15

Purpose: Proton CT (pCT) has the potential to accurately measure the electron density map of tissues at low doses but the spatial resolution is prohibitive if the curved paths of protons in matter is not accounted for. The authors propose to account for an estimate of the most likely path of protons in a filtered backprojection (FBP) reconstruction algorithm. Methods: The energy loss of protons is first binned in several proton radiographs at different distances to the proton source to exploit the depth-dependency of the estimate of the most likely path. This process is named the distance-driven binning. A voxel-specific backprojection is then used to select the adequate radiograph in the distance-driven binning in order to propagate in the pCT image the best achievable spatial resolution in proton radiographs. The improvement in spatial resolution is demonstrated using Monte Carlo simulations of resolution phantoms. Results: The spatial resolution in the distance-driven binning depended on the distance of the objects from the source and was optimal in the binned radiograph corresponding to that distance. The spatial resolution in the reconstructed pCT images decreased with the depth in the scanned object but it was always better than previous FBP algorithms assuming straight line paths. In a water cylinder with 20 cm diameter, the observed range of spatial resolutions was 0.7 - 1.6 mm compared to 1.0 - 2.4 mm at best with a straight line path assumption. The improvement was strongly enhanced in shorter 200 Degree-Sign scans. Conclusions: Improved spatial resolution was obtained in pCT images with filtered backprojection reconstruction using most likely path estimates of protons. The improvement in spatial resolution combined with the practicality of FBP algorithms compared to iterative reconstruction algorithms makes this new algorithm a candidate of choice for clinical pCT.

Cerebral perfusion computed tomography deconvolution via structure tensor total variation regularization

Energy Technology Data Exchange (ETDEWEB)

Zeng, Dong; Zhang, Xinyu; Bian, Zhaoying, E-mail: zybian@smu.edu.cn, E-mail: jhma@smu.edu.cn; Huang, Jing; Zhang, Hua; Lu, Lijun; Lyu, Wenbing; Feng, Qianjin; Chen, Wufan; Ma, Jianhua, E-mail: zybian@smu.edu.cn, E-mail: jhma@smu.edu.cn [Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515, China and Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, Guangdong 510515 (China); Zhang, Jing [Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052 (China)

2016-05-15

Purpose: Cerebral perfusion computed tomography (PCT) imaging as an accurate and fast acute ischemic stroke examination has been widely used in clinic. Meanwhile, a major drawback of PCT imaging is the high radiation dose due to its dynamic scan protocol. The purpose of this work is to develop a robust perfusion deconvolution approach via structure tensor total variation (STV) regularization (PD-STV) for estimating an accurate residue function in PCT imaging with the low-milliampere-seconds (low-mAs) data acquisition. Methods: Besides modeling the spatio-temporal structure information of PCT data, the STV regularization of the present PD-STV approach can utilize the higher order derivatives of the residue function to enhance denoising performance. To minimize the objective function, the authors propose an effective iterative algorithm with a shrinkage/thresholding scheme. A simulation study on a digital brain perfusion phantom and a clinical study on an old infarction patient were conducted to validate and evaluate the performance of the present PD-STV approach. Results: In the digital phantom study, visual inspection and quantitative metrics (i.e., the normalized mean square error, the peak signal-to-noise ratio, and the universal quality index) assessments demonstrated that the PD-STV approach outperformed other existing approaches in terms of the performance of noise-induced artifacts reduction and accurate perfusion hemodynamic maps (PHM) estimation. In the patient data study, the present PD-STV approach could yield accurate PHM estimation with several noticeable gains over other existing approaches in terms of visual inspection and correlation analysis. Conclusions: This study demonstrated the feasibility and efficacy of the present PD-STV approach in utilizing STV regularization to improve the accuracy of residue function estimation of cerebral PCT imaging in the case of low-mAs.

Comparison of procalcitonin and different guidelines for first febrile urinary tract infection in children by imaging.

Science.gov (United States)

Liao, Pei-Fen; Ku, Min-Sho; Tsai, Jeng-Dau; Choa, Yu-Hua; Hung, Tung-Wei; Lue, Ko-Huang; Sheu, Ji-Nan

2014-09-01

We examined the ability of a procalcitonin (PCT) protocol to detect vesicoureteral reflux (VUR) and renal scarring (RS), evaluated procedural costs and radiation burden, and compared four representative guidelines for children with their first febrile urinary tract infection (UTI). Children aged ≤2 years with their first febrile UTI who underwent renal ultrasonography (US), acute and late technetium-99m ((99m)Tc)-dimercaptosuccinic acid scan, and voiding cystourethrography were prospectively studied. The representative guidelines applied in a retrospective simulation included the American Academy of Pediatrics (AAP), National Institute of Clinical Excellence, top-down approach (TDA), and Italian Society of Pediatric Nephrology (ISPN). These were compared in terms of ability to detect abnormalities, procedural costs and radiation. Of 278 children analyzed, 172 (61.9%) had acute pyelonephritis. There was VUR in 101 (36.3%) children, including 73 (26.3%) with grades III-V VUR. RS was identified in 75 (27.0%) children. To detect VUR, TDA and PCT had the highest sensitivity for grades I-V VUR (80.2%) and III-V VUR (94.5%), respectively, whereas AAP had the highest specificity for I-V VUR (77.4%) and III-V VUR (78.0%), respectively. TDA and PCT had the highest sensitivity (100%) for detecting RS. The highest cost and radiation dose was associated with TDA, whereas AAP had the least expenditure and radiation exposure. By multivariate analysis, PCT and VUR, especially grades III-V, were independent predictors of RS. There is no perfect guideline for first febrile UTI children. The PCT protocol has good ability for detecting high-grade VUR and RS. If based on available imaging modalities and reducing cost and radiation burden, clinical suggestions in the AAP guidelines represent a considerable protocol.

Interleukin-6 and procalcitonin as biomarkers in mortality prediction of hospitalized patients with community acquired pneumonia

Directory of Open Access Journals (Sweden)

Ilija Andrijevic

2014-01-01

Full Text Available Introduction: Community acquired pneumonia (CAP may present as life-threatening infection with uncertain progression and outcome of treatment. Primary aim of the trial was determination of the cut-off value of serum interleukin-6 (IL-6 and procalcitonin (PCT above which, 30-day mortality in hospitalized patients with CAP, could be predicted with high sensitivity and specificity. We investigated correlation between serum levels of IL-6 and PCT at admission and available scoring systems of CAP (pneumonia severity index-PSI, modified early warning score-MEWS and (Confusion, Urea nitrogen, respiratory rate, Blood pressure, ≥65 years of age-CURB65. Methods: This was prospective, non-randomized trial which included 101 patients with diagnosed CAP. PSI, MEWS and CURB65 were assessed on first day of hospitalization. IL-6 and PCT were also sampled on the first day of hospitalization. Results: Based on ROC curve analysis (AUC ± SE = 0.934 ± 0.035; 95%CI(0.864-1.0; P = 0.000 hospitalized CAP patients with elevated IL-6 level have 93.4% higher risk level for lethal outcome. Cut-off value of 20.2 pg/ml IL-6 shows sensitivity of 84% and specificity of 87% in mortality prediction. ROC curve analysis confirmed significant role of procalcitonin as a mortality predictor in CAP patients (AUC ± SE = 0.667 ± 0.062; 95%CI(0.546-0.789; P = 0.012. Patients with elevated PCT level have 66.7% higher risk level for lethal outcome. As a predictor of mortality at the cut-off value of 2.56 ng/ml PCT shows sensitivity of 76% and specificity of 61.8%. Conclusions: Both IL-6 and PCI are significant for prediction of 30-day mortality in hospitalized patients with CAP. Serum levels of IL6 correlate with major CAP scoring systems.

The risk stratification and prognostic evaluation of soluble programmed death-1 on patients with sepsis in emergency department.

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Zhao, Yongzhen; Jia, Yumei; Li, Chunsheng; Fang, Yingying; Shao, Rui

2018-01-01

To evaluate the efficacy of soluble programmed death-1 (sPD-1) for risk stratification and prediction of 28-day mortality in patients with sepsis, we compared serum sPD-1 with procalcitonin (PCT), C-reactive protein (CRP), and the Mortality in Emergency Department Sepsis (MEDS) score. A total of 60 healthy volunteers and 595 emergency department (ED) patients were recruited for this prospective cohort study. According to the severity of their condition on ED arrival, the patients were allocated to the systemic inflammatory response syndrome group (130 cases), sepsis group (276 cases), severe sepsis group (121 cases), and septic shock group (68 cases). In addition, all patients with sepsis were also divided into the survivor group (349 cases) and nonsurvivor group (116 cases) according to the 28-day outcomes. When the severity of sepsis increased, the levels of sPD-1 gradually increased. The levels of sPD-1, PCT, CRP and the MEDS score were also higher in the nonsurvivor group compared to the survivor group. Logistic regression suggested that sPD-1, PCT, and the MEDS score were independent risk factors for 28-day mortality of patients with sepsis. Area under the curve (AUC) of sPD-1, PCT and the MEDS score for 28-day mortality was 0.725, 0.693, and 0.767, respectively, and the AUC was improved when all 3 factors were combined (0.843). Serum sPD-1 is positively correlated with the severity of sepsis, and it is valuable for risk stratification of patients and prediction of 28-day mortality. Combining sPD-1 with PCT and the MEDS score improves the prognostic evaluation. Copyright © 2017 Elsevier Inc. All rights reserved.

Adjunctive role of preoperative liver magnetic resonance imaging for potentially resectable pancreatic cancer.

Science.gov (United States)

Kim, Hyoung Woo; Lee, Jong-Chan; Paik, Kyu-Hyun; Kang, Jingu; Kim, Young Hoon; Yoon, Yoo-Seok; Han, Ho-Seong; Kim, Jaihwan; Hwang, Jin-Hyeok

2017-06-01

The adjunctive role of magnetic resonance imaging of the liver before pancreatic ductal adenocarcinoma has been unclear. We evaluated whether the combination of hepatic magnetic resonance imaging with multidetector computed tomography using a pancreatic protocol (pCT) could help surgeons select appropriate candidates and decrease the risk of early recurrence. We retrospectively enrolled 167 patients in whom complete resection was achieved without grossly visible residual tumor; 102 patients underwent pCT alone (CT group) and 65 underwent both hepatic magnetic resonance imaging and pCT (magnetic resonance imaging group). By adding hepatic magnetic resonance imaging during preoperative evaluation, hepatic metastases were newly discovered in 3 of 58 patients (5%) without hepatic lesions on pCT and 17 of 53 patients (32%) with indeterminate hepatic lesions on pCT. Patients with borderline resectability, a tumor size >3 cm, or preoperative carbohydrate antigen 19-9 level >1,000 U/mL had a greater rate of hepatic metastasis on subsequent hepatic magnetic resonance imaging. Among 167 patients in whom R0/R1 resection was achieved, the median overall survival was 18.2 vs 24.7 months (P = .020) and the disease-free survival was 8.5 vs 10.0 months (P = .016) in the CT and magnetic resonance imaging groups, respectively (median follow-up, 18.3 months). Recurrence developed in 82 (80%) and 43 (66%) patients in the CT and magnetic resonance imaging groups, respectively. The cumulative hepatic recurrence rate was greater in the CT group than in the magnetic resonance imaging group (P magnetic resonance imaging should be considered in patients with potentially resectable pancreatic ductal adenocarcinoma, especially those with high tumor burden. Copyright © 2017 Elsevier Inc. All rights reserved.

Palliative Radiotherapy in the Presence of Well-Controlled Metastatic Disease after Initial Chemotherapy May Prolong Survival in Patients with Metastatic Esophageal and Gastric Cancer.

Science.gov (United States)

Hingorani, Mohan; Dixit, Sanjay; Johnson, Miriam; Plested, Victoria; Alty, Kevin; Colley, Peter; Beavis, Andrew W; Roy, Rajarshi; Maraveyas, Anthony

2015-10-01

We report the outcomes of patients treated with palliative radiotherapy (pRT) to the primary tumour in the context of well-controlled metastatic disease after initial chemotherapy. Clinical records of 132 patients with metastatic esophago-gastric (OG) cancer treated with palliative chemotherapy (pCT) between January 2009 and June 2013 were reviewed. Ninetyseven patients had responding or stable disease after 3 months of chemotherapy, of whom 53 patients received pRT to the primary tumour after initial chemotherapy in the presence of well-controlled metastatic disease (group A, pCT-RT). The remaining 44 patients were treated with pCT alone (group B, pCT). Treatment-related outcomes were assessed in above groups including time to local progression (TTLP), progression-free and overall survival. The median overall survival for patients treated with pRT after initial chemotherapy (group A) was 23.3 months (95% confidence interval [CI], 17.70 to 28.89 months) and significantly higher than the 14 months (95% CI, 10.91 to 17.08 months) in patients treated with pCT alone (group B) (p < 0.001). The use of pCT-RT was an independent predictor of OS in multivariate analysis. Local recurrence was observed in 12/53 of patients (23%) in group A compared to 16/44 (36%) in group B. The median TTLP was significantly higher in patients after pCT-RT at 17.3 months (5.23 months to 44.50 months) compared to 8.3 months (range, 4.10 to 25.23 months) in patients treated with pCT alone (p=0.006). The possibility of pRT influencing systemic disease in advanced OG cancer has not been reported, and results from the present study present strong arguments for investigation of this therapeutic strategy in a randomized trial.

Microstructure of Precipitation Hardenable Powder Metallurgical Ni Alloys Containing 35 to 45 pct Cr and 3.5 to 6 pct Nb

DEFF Research Database (Denmark)

Bihlet, Uffe Ditlev; Dahl, Kristian Vinter; Somers, Marcel A. J.

2014-01-01

the additional presence of metastable γ'' (Ni3Nb). A co-dependent growth morphology was found, where the preferred growth direction of γ'', the {001} planes of γ-Ni, caused precipitates of both α-Cr and d to appear in the form of mutually perpendicular oriented disks or plates. Solution heat treatment at 1373 K...

Diagnostic and prognostic accuracy of clinical and laboratory parameters in community-acquired pneumonia

Directory of Open Access Journals (Sweden)

Nusbaumer Charly

2007-03-01

Full Text Available Abstract Background Community-acquired pneumonia (CAP is the most frequent infection-related cause of death. The reference standard to diagnose CAP is a new infiltrate on chest radiograph in the presence of recently acquired respiratory signs and symptoms. This study aims to evaluate the diagnostic and prognostic accuracy of clinical signs and symptoms and laboratory biomarkers for CAP. Methods 545 patients with suspected lower respiratory tract infection, admitted to the emergency department of a university hospital were included in a pre-planned post-hoc analysis of two controlled intervention trials. Baseline assessment included history, clinical examination, radiography and measurements of procalcitonin (PCT, highly sensitive C-reactive protein (hsCRP and leukocyte count. Results Of the 545 patients, 373 had CAP, 132 other respiratory tract infections, and 40 other final diagnoses. The AUC of a clinical model including standard clinical signs and symptoms (i.e. fever, cough, sputum production, abnormal chest auscultation and dyspnea to diagnose CAP was 0.79 [95% CI, 0.75–0.83]. This AUC was significantly improved by including PCT and hsCRP (0.92 [0.89–0.94]; p Conclusion PCT, and to a lesser degree hsCRP, improve the accuracy of currently recommended approaches for the diagnosis of CAP, thereby complementing clinical signs and symptoms. PCT is useful in the severity assessment of CAP.

Reduced Calibration Curve for Proton Computed Tomography

International Nuclear Information System (INIS)

Yevseyeva, Olga; Assis, Joaquim de; Evseev, Ivan; Schelin, Hugo; Paschuk, Sergei; Milhoretto, Edney; Setti, Joao; Diaz, Katherin; Hormaza, Joel; Lopes, Ricardo

2010-01-01

The pCT deals with relatively thick targets like the human head or trunk. Thus, the fidelity of pCT as a tool for proton therapy planning depends on the accuracy of physical formulas used for proton interaction with thick absorbers. Although the actual overall accuracy of the proton stopping power in the Bethe-Bloch domain is about 1%, the analytical calculations and the Monte Carlo simulations with codes like TRIM/SRIM, MCNPX and GEANT4 do not agreed with each other. A tentative to validate the codes against experimental data for thick absorbers bring some difficulties: only a few data is available and the existing data sets have been acquired at different initial proton energies, and for different absorber materials. In this work we compare the results of our Monte Carlo simulations with existing experimental data in terms of reduced calibration curve, i.e. the range - energy dependence normalized on the range scale by the full projected CSDA range for given initial proton energy in a given material, taken from the NIST PSTAR database, and on the final proton energy scale - by the given initial energy of protons. This approach is almost energy and material independent. The results of our analysis are important for pCT development because the contradictions observed at arbitrary low initial proton energies could be easily scaled now to typical pCT energies.

Effect of Smaller Left Ventricular Capture Threshold Safety Margins to Improve Device Longevity in Recipients of Cardiac Resynchronization-Defibrillation Therapy.

Science.gov (United States)

Steinhaus, Daniel A; Waks, Jonathan W; Collins, Robert; Kleckner, Karen; Kramer, Daniel B; Zimetbaum, Peter J

2015-07-01

Device longevity in cardiac resynchronization therapy (CRT) is affected by the pacing capture threshold (PCT) and programmed pacing amplitude of the left ventricular (LV) pacing lead. The aims of this study were to evaluate the stability of LV pacing thresholds in a nationwide sample of CRT defibrillator recipients and to determine potential longevity improvements associated with a decrease in the LV safety margin while maintaining effective delivery of CRT. CRT defibrillator patients in the Medtronic CareLink database were eligible for inclusion. LV PCT stability was evaluated using ≥2 measurements over a 14-day period. Separately, a random sample of 7,250 patients with programmed right atrial and right ventricular amplitudes ≤2.5 V, LV thresholds ≤ 2.5 V, and LV pacing ≥90% were evaluated to estimate theoretical battery longevity improvement using LV safety margins of 0.5 and 1.5 V. Threshold stability analysis in 43,256 patients demonstrated LV PCT stability of 1 V had the greatest increases in battery life (mean increase 0.86 years, 95% confidence interval 0.85 to 0.87). In conclusion, nearly all CRT defibrillator patients had LV PCT stability <1.0 V. Decreasing the LV safety margin from 1.5 to 0.5 V provided consistent delivery of CRT for most patients and significantly improved battery longevity. Copyright © 2015 Elsevier Inc. All rights reserved.

Adaptive radiotherapy with an average anatomy model: Evaluation and quantification of residual deformations in head and neck cancer patients

International Nuclear Information System (INIS)

Kranen, Simon van; Mencarelli, Angelo; Beek, Suzanne van; Rasch, Coen; Herk, Marcel van; Sonke, Jan-Jakob

2013-01-01

Background and purpose: To develop and validate an adaptive intervention strategy for radiotherapy of head-and-neck cancer that accounts for systematic deformations by modifying the planning-CT (pCT) to the average misalignments in daily cone beam CT (CBCT) measured with deformable registration (DR). Methods and materials: Daily CBCT scans (808 scans) for 25 patients were retrospectively registered to the pCT with B-spline DR. The average deformation vector field ( ) was used to deform the pCT for adaptive intervention. Two strategies were simulated: single intervention after 10 fractions and weekly intervention with an from the previous week. The model was geometrically validated with the residual misalignment of anatomical landmarks both on bony-anatomy (BA; automatically generated) and soft-tissue (ST; manually identified). Results: Systematic deformations were 2.5/3.4 mm vector length (BA/ST). Single intervention reduced deformations to 1.5/2.7 mm (BA/ST). Weekly intervention resulted in 1.0/2.2 mm (BA/ST) and accounted better for progressive changes. 15 patients had average systematic deformations >2 mm (BA): reductions were 1.1/1.9 mm (single/weekly BA). ST improvements were underestimated due to observer and registration variability. Conclusions: Adaptive intervention with a pCT modified to the average anatomy during treatment successfully reduces systematic deformations. The improved accuracy could possibly be exploited in margin reduction and/or dose escalation

Necrotizing Pseudomonas aeruginosa Community-Acquired Pneumonia: A Case Report and Review of the Literature

Directory of Open Access Journals (Sweden)

Satish Maharaj

2017-01-01

Full Text Available Lung cavities are not typically associated with community-acquired pneumonia (CAP. CAP due to P. aeruginosa is rare and even less commonly causes necrotizing pneumonia. We report a case of P. aeruginosa CAP that progressed to necrotizing pneumonia and was eventually fatal. Procalcitonin (PCT has been well investigated in guiding antibiotic therapy (especially CAP in adults. In this case, PCT at presentation and sequentially was negative. We discuss this caveat and present hypotheses as to the sensitivity and specificity of PCT and C-reactive protein (CRP in these patients. To better characterize P. aeruginosa CAP, we undertook a review of cases indexed in PubMed from 2001 to 2016 (n=9. The data reveal that risk factors for P. aeruginosa CAP include smoking, alcohol use, obstructive lung disease, sinusitis, and hot tub use. The route of infection for P. aeruginosa CAP remains unknown. One of the most interesting findings on reviewing cases was that P. aeruginosa CAP involves the right upper lobe in the vast majority. We suggest that when physicians in the community see patients with distinctly upper lobe necrotizing or cavitary pneumonia, they should consider P. aeruginosa in their differential diagnosis. Further studies are needed to clarify route of infection, role of PCT and CRP, and optimal therapy including drug and duration.

Procalcitonin levels in gram-positive, gram-negative, and fungal bloodstream infections.

Science.gov (United States)

Leli, Christian; Ferranti, Marta; Moretti, Amedeo; Al Dhahab, Zainab Salim; Cenci, Elio; Mencacci, Antonella

2015-01-01

Procalcitonin (PCT) can discriminate bacterial from viral systemic infections and true bacteremia from contaminated blood cultures. The aim of this study was to evaluate PCT diagnostic accuracy in discriminating Gram-positive, Gram-negative, and fungal bloodstream infections. A total of 1,949 samples from patients with suspected bloodstream infections were included in the study. Median PCT value in Gram-negative (13.8 ng/mL, interquartile range (IQR) 3.4-44.1) bacteremias was significantly higher than in Gram-positive (2.1 ng/mL, IQR 0.6-7.6) or fungal (0.5 ng/mL, IQR 0.4-1) infections (P Gram-negatives from Gram-positives at the best cut-off value of 10.8 ng/mL and an AUC of 0.944 (95% CI 0.919-0.969, P Gram-negatives from fungi at the best cut-off of 1.6 ng/mL. Additional results showed a significant difference in median PCT values between Enterobacteriaceae and nonfermentative Gram-negative bacteria (17.1 ng/mL, IQR 5.9-48.5 versus 3.5 ng/mL, IQR 0.8-21.5; P Gram-negative from Gram-positive and fungal bloodstream infections. Nevertheless, its utility to predict different microorganisms needs to be assessed in further studies.

Renal versus splenic maximum slope based perfusion CT modelling in patients with portal-hypertension

Energy Technology Data Exchange (ETDEWEB)

Fischer, Michael A. [University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Zurich (Switzerland); Karolinska Institutet, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm (Sweden); Brehmer, Katharina [Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden); Svensson, Anders; Aspelin, Peter; Brismar, Torkel B. [Karolinska Institutet, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm (Sweden); Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden)

2016-11-15

To assess liver perfusion-CT (P-CT) parameters derived from peak-splenic (PSE) versus peak-renal enhancement (PRE) maximum slope-based modelling in different levels of portal-venous hypertension (PVH). Twenty-four patients (16 men; mean age 68 ± 10 years) who underwent dynamic P-CT for detection of hepatocellular carcinoma (HCC) were retrospectively divided into three groups: (1) without PVH (n = 8), (2) with PVH (n = 8), (3) with PVH and thrombosis (n = 8). Time to PSE and PRE and arterial liver perfusion (ALP), portal-venous liver perfusion (PLP) and hepatic perfusion-index (HPI) of the liver and HCC derived from PSE- versus PRE-based modelling were compared between the groups. Time to PSE was significantly longer in PVH groups 2 and 3 (P = 0.02), whereas PRE was similar in groups 1, 2 and 3 (P > 0.05). In group 1, liver and HCC perfusion parameters were similar for PSE- and PRE-based modelling (all P > 0.05), whereas significant differences were seen for PLP and HPI (liver only) in group 2 and ALP in group 3 (all P < 0.05). PSE is delayed in patients with PVH, resulting in a miscalculation of PSE-based P-CT parameters. Maximum slope-based P-CT might be improved by replacing PSE with PRE-modelling, whereas the difference between PSE and PRE might serve as a non-invasive biomarker of PVH. (orig.)

Corrosion of a Pu-doped zirconolite-rich ceramic

International Nuclear Information System (INIS)

Bakel, A.J.; Buck, E.C.; Wolf, S.F.; Chamberlain, D.B.; Bates, J.K.; Ebbinghaus, B.B.

1997-01-01

As part of a large Pu disposition program, a zirconolite-rich titanate ceramic is being developed at Lawrence Livermore National Laboratory (LLNL) as a possible immobilization material. This same material is being tested at Argonne National Laboratory (ANL). The goal of this study is to describe the corrosion behavior of this ceramic, particularly the release of Pu and Gd, using results from several static corrosion tests (MCC-1, PCT-A, and PCT-B). The release of relatively large amounts of Al, Ba, and Ca in short-term tests (3 day MCC-1 and 7 day PCT-A) indicates that these elements are released from grain boundaries or from highly soluble phases. Results from long-term (28, 98, and 182 day) PCT-B show that the releases of Al, Ba, and Ca decrease with time, the releases of U and Zr increase with time, and that the releases of Cs, Gd, Mo, and Pu remain fairly constant. Formation of alteration phases may lead to the decrease of Ba and Ca in leachate solutions. Due to the heterogeneous nature of the material, the formation of alteration phases, and the inherently low solubility of several elements, no element(s) could be recommended as good markers for the overall corrosion of this ceramic. Data show that, due to the complex nature of this material, the release of each element should be considered separately

Usefulness of procalcitonin and C-reactive protein for predicting bacteremia in urinary tract infections in the emergency department.

Science.gov (United States)

Julián-Jiménez, A; Gutiérrez-Martín, P; Lizcano-Lizcano, A; López-Guerrero, M A; Barroso-Manso, Á; Heredero-Gálvez, E

2015-10-01

The aim of this study was to analyze and compare the capacity of procalcitonin (PCT), C-reactive protein (CRP), lactate and leukocytes to predict the presence of bacteremia in patients with urinary tract infections (UTIs). Observational, retro-prospective analytical study of adult patients (≥15 years) diagnosed with UTI in an emergency department from August 2012 to January 2013. The study included 328 patients diagnosed with UTI, with a mean age of 52±22 years, 74% of whom were women. Of these, 43 (13.1%) had bacteremia. For predicting bacteremia, PCT achieved the largest area under the receiver operating characteristic curve (ROC-AUC) at .993 (95% CI .987-1; P<.001). A cutoff≥1.16ng/mL achieves a sensitivity of 100%, a specificity of 97%, a positive predictive value of 84% and a negative predictive value of 100%. Lactate achieved an ROC-AUC of .844, and CRP achieved only .534. The mean values when comparing PCT levels in patients with UTIs with and without bacteremia were 8.08±16.37 and .34±.37ng/mL, respectively (P<.001). For patients with UTIs in the emergency department, PCT achieves considerable diagnostic performance for suspecting bacteremia, a performance greater than that of lactate, CRP and leukocytes. Copyright © 2015 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Analytical evaluation of the novel Lumipulse G BRAHMS procalcitonin immunoassay

OpenAIRE

Ruzzenente, Orazio; Salvagno, Gian Luca; Gelati, Matteo; Lippi, Giuseppe

2016-01-01

Objectives: This study was designed to evaluate the analytical performance of the novel Lumipulse G1200 BRAHMS procalcitonin (PCT) immunoassay. Design and methods: This analytical evaluation encompassed the calculation of the limit of blank (LOB), limit of detection (LOD), functional sensitivity, intra- and inter-assay imprecision, confirmation of linearity and a comparison with the Vidas BRAHMS PCT assay. Results: The LOB, LOD and functional sensitivity were 0.0010 ng/mL, 0.0016 ng/mL and ...

Implementation of physical coordination training and cognitive behavioural training interventions at cleaning workplaces - secondary analyses of a randomised controlled trial

DEFF Research Database (Denmark)

Jørgensen, Marie B; Faber, Anne; Jespersen, Tobias

2012-01-01

intervention effects, more research on implementation is needed. Trial registration: ISRCTN96241850. Practitioner summary: Both physical coordination training and cognitive behavioural training are potential effective workplace interventions among low educated job groups with high physical work demands......This study evaluates the implementation of physical coordination training (PCT) and cognitive behavioural training (CBTr) interventions in a randomised controlled trial at nine cleaners' workplaces. Female cleaners (n = 294) were randomised into a PCT, a CBTr or a reference (REF) group. Both 12...

Experimental Investigation of the 1073 K (800 °C) Isothermal Section of the Al-V-Zr Ternary System

Science.gov (United States)

Zhu, Yude; Ouyang, Xuemei; Yin, Fucheng; Zhao, Manxiu; Lou, Jia

2018-03-01

This work is focused on an experimental investigation of the phase equilibria of the Al-V-Zr system at 1073 K (800 °C). The phase equilibria were analyzed using scanning electron microscopy (SEM) coupled with energy-dispersive spectrometry and X-ray diffraction. The results confirmed the presence of twelve three-phase regions and one ternary compound, Τ, which contains 10.0 to 16.5 at. pct Zr, 52.8 to 55.2 at. pct Al, and 29.3 to 36.3 at. pct V. The T phase can be in equilibrium with Al8V5, Al3Zr, Al2Zr, and α-V. The T phase belongs to the tetragonal crystal system with confirmed lattice parameters of a = 0.658531 nm and c = 0.517334 nm. The Al2Zr phase region is extraordinarily large and can be in equilibrium with all the compounds in the Al-Zr and V-Zr systems, with the exception of the AlZr phase.

Patch-based generation of a pseudo CT from conventional MRI sequences for MRI-only radiotherapy of the brain

DEFF Research Database (Denmark)

Andreasen, Daniel; Van Leemput, Koen; Hansen, Rasmus H.

2015-01-01

scans. In this study, we investigate the potential of a patch-based method for creating a pCT based on conventional T1-weighted MRI scans without using deformable registrations. We compare this method against two state-of-the-art methods within the voxel-based and atlas-based categories. Methods...... based on water equivalent path lengths was carried out, comparing the upper hemisphere of the head in the pCT and the real CT. Finally, the dosimetric accuracy was tested and compared for a photon treatment plan. Results:The pCTs produced with the patch-based method had the best voxel-wise, geometric......Purpose: In radiotherapy (RT) based on magnetic resonance imaging (MRI) as the only modality, the information on electron density must be derived from the MRI scan by creating a so-called pseudo computed tomography (pCT). This is a nontrivial task, since the voxel-intensities in an MRI scan...

Effect of modified mold shell on the microstructure and tensile fracture morphology of single-crystal nickel-base superalloy

Science.gov (United States)

Xu, Weitai; Zhao, Yutao; Sun, Shaochun; Liu, Manping; Ma, Dexin; Liang, Xiangfeng; Wang, Cunlong; Tao, Ran

2018-04-01

The mold shell used for single-crystal turbine blades preparation was modified from conventional process to fiber reinforcement technology. The wall thickness was decreased by 32.3 percent (pct) than the conventional process. Then these two mold shells were used to produce single crystal samples of nickel-base superalloy in a Bridgman furnace. The local temperature curves were recorded in the process. The results show that the modified mold shell can increase the temperature gradient in the mushy zone than the conventional mold shell. The primary and secondary dendrite arm space were reduced by 8 pct and 12 pct, respectively. Moreover, both the area fraction and mean size of the γ‧/γ eutectic were declined, as well as the dendritic segregation tendency. Therefore it contributed to the lower residual eutectic and micro-porosity in the heat-treated microstructure. Further, fracture surface of the samples made by modified mold shell exhibited smaller facets and more uniform dimples in the size and shape.

Visualization of muscles involved in unilateral tremor using 13N-ammonia and positron emission tomography

International Nuclear Information System (INIS)

Schelstraete, K.; Simons, M.; Deman, J.; Vermeulen, F.L.; Ghent Rijksuniversiteit; Goethals, P.; Bratzlavsky, M.

1982-01-01

Using positron emission computerized tomography (PCT), a high uptake of IV injected 13 N-ammonia was observed in the muscles of the right forearm and leg of a patient with a rightsided static tremor. In some mucles the concentration of 13 NH 3 was 8.5 times higher than in the symmetrical normal limb. Confrontation of the clinical, neurological, and electroyographic findings with the results of the PCT proved that the muscles with the high uptake corresponded to the muscles responsible for the tremulous movements. There is strong evidence that the high uptake of 13 NH 3 was related to the increased blood flow produced by the continuous rhythmic exercise of the muscles involved in the tremor. To our knowledge a similar observation has not been described before. It is suggested that the combined use of suitable positron emitters and PCT might provide a valuable tool for the noninvasive study of perfusion of individual skeletal muscles. (orig.)

The development of English primary care group governance. A scenario analysis.

Science.gov (United States)

Sheaff, R

1999-01-01

At present there is a policy vacuum about what English Primary Care Groups' (PCGs) governance will be when they develop into Primary Care Trusts (PCTs). Draft legislation leaves many options open, so PCT governance is likely to 'emerge' as PCTs are created. It also remains uncertain how general practitioners (GPs) will react to the formation of PCTs and how the UK government will then respond in turn. A scenario analysis suggests three possible lines of development. The base (likeliest) scenario predicts a mainly networked form of PCT governance. An alternative scenario is of PCT governance resembling the former National Health Service internal market. A third scenario predicts 'franchise model' PCTs employing some GPs and subcontracting others. To different degrees all three scenarios predict that PCTs will retain elements of networked governance. If it fails to make GPs as accountable to NHS management as the UK government wishes, networked governance may prove only a transitional stage before English PCTs adopt either quasi-market or hierarchical governance.

Open Tracheostomy after Aborted Percutaneous Approach due to Tracheoscopy Revealing Occult Tracheal Wall Ulcer

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John Schweiger

2013-01-01

Full Text Available Tracheostomy is a common procedure for intensive care patients requiring prolonged mechanical ventilation. In this case report, we describe a 78-year-old female patient admitted for an aneurysm of the cerebral anterior communicating artery. Following immediate endovascular coiling, she remained ventilated and was transferred to the neurological intensive care unit. On postoperative day ten, a percutaneous tracheostomy (PCT was requested; however, a large ulcer or possible tracheoesophageal fistula was identified on the posterior tracheal wall following bronchoscopic assessment of the trachea. Therefore, the requested PCT procedure was aborted. An open tracheostomy in the operating room was completed; however, due to the position and depth of the ulcer, a reinforced endotracheal tube (ETT was placed via the tracheostomy. Four days later, the reinforced ETT was replaced with a Shiley distal extended tracheostomy tube to bypass the ulceration. Careful inspection and evaluation of the tracheostomy site before PCT prevented a potentially life-threatening issue in our patient.

Value of procalcitonin, C-reactive protein, and neopterin in exacerbations of chronic obstructive pulmonary disease

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Alicia Lacoma

2011-02-01

Full Text Available Alicia Lacoma1,4, Cristina Prat1,4, Felipe Andreo2,4, Luis Lores3, Juan Ruiz-Manzano2,4, Vicente Ausina1,4, Jose Domínguez1,41Servei de Microbiologia, 2Servei de Pneumologia, Hospital Universitari Germans Trias i Pujol, Fundació Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Spain; 3Servei de Pneumologia, Hospital de Sant Boi, Sant Boi de Llobregat, Spain; 4CIBER Enfermedades Respiratorias (CIBERES, Instituto de Salud Carlos III, Madrid, SpainObjective: The identification of biological markers in order to assess different aspects of COPD is an area of growing interest. The objective of this study was to investigate whether levels of procalcitonin (PCT, C-reactive protein (CRP, and neopterin in COPD patients could be useful in identifying the etiological origin of the exacerbation and assessing its prognosis.Methods: We included 318 consecutive COPD patients: 46 in a stable phase, 217 undergoing an exacerbation, and 55 with pneumonia. A serum sample was collected from each patient at the time of being included in the study. A second sample was also collected 1 month later from 23 patients in the exacerbation group. We compared the characteristics, biomarker levels, microbiological findings, and prognosis in each patient group. PCT and CRP were measured using an immunofluorescence assay. Neopterin levels were measured using a competitive immunoassay.Results: PCT and CRP showed significant differences among the three patient groups, being higher in patients with pneumonia, followed by patients with exacerbation (P < 0.0001. For the 23 patients with paired samples, PCT and CRP levels decreased 1 month after the exacerbation episode, while neopterin increased. Neopterin showed significantly lower levels in exacerbations with isolation of pathogenic bacteria, but no differences were found for PCT and CRP. No significant differences were found when comparing biomarker levels

肝癌合并肝硬化患者血小板参数的变化及影响因素

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DING Shengnan

2014-06-01

Full Text Available ObjectiveTo analyze the changes in platelet parameters and their influential factors in cirrhotic patients with hepatocellular carcinoma (HCC. MethodsThe clinical data of 602 cirrhotic patients with HCC who were admitted to the First Hospital of Jilin University from January 2011 to December 2012, as well as 200 cirrhotic patients hospitalized during the same period, were collected. Statistical analysis was performed using SPSS 19.0. Normally distributed continuous data were expressed as mean ± standard deviation; comparison between two groups was made by t test, and comparison between multiple groups was made by analysis of variance. Non-normally distributed data were expressed as median and interquartile range (P25-P75; comparison between groups was made by rank sum test. ResultsCompared with the cirrhotic group, the HCC group had significantly higher platelet count (PLT and plateletcrit (PCT (t=5.019, P=0000; t=5.017, P=0.000 and a significantly lower mean platelet volume (MPV/PLT (t=5.877, P=0.000; there were no significant differences in MPV and platelet distribution width between the two groups (t=-0.942, P=0.347; t=-1.040, P=0.298. The receiver operating characteristic (ROC analysis showed that the area under the ROC curve was 0.636 for PLT, 0.633 for PCT, and 0.639 for MPV/PLT in the diagnosis of HCC in cirrhotic patients. Decreases in PLT and PCT were closely related to hepatitis C virus (HCV infection. Patients with Child-Pugh class A cirrhosis had significantly higher PLT and PCT than those with Child-Pugh class B and C cirrhosis (P＜0.01; patients with a maximum tumor diameter of ≥5 cm had significantly higher PLT and PCT than those with maximum tumor diameters of 2-5 cm and ≤2 cm (P＜0.01. Patients with Child-Pugh class A cirrhosis had a significantly lower MPV/PLT than those with Child-Pugh class B and C cirrhosis (P＜0.01; patients with a maximum tumor diameter of ≥5 cm had a significantly lower MPV/PLT than those

Detection and diagnositic value of serum procalciton in and C-reacti protein in children with nervous system infection%降钙素原、C-反应蛋白诊断小儿中枢神经系统感染的价值

Institute of Scientific and Technical Information of China (English)

郑秀霞

2012-01-01

Objective To investigate the clinical value of serum procalcitonin(PCT) and C-reactive protein (CRP) piagnosis of in children with acute bacterial meningitis and virus meningitis.Methods The serum PCT and CRP levels in 30 children with acute bacterial meningitis and 30 children with virus meningitis were measured by electrochemiluminescence immune assay(ECLIA) and compared with 30 healthy children(control group).Results The level of serum PCT in bacterial meningitis group was significantly higher than that in control group and viral meningitis group(t =7.67,5.67,P ＜ 0.01 ).The level of CRP in bacterial meningitis group and viral meningitis group was higher than that in control group ( t =2.52,2.47,P ＜ 0.05 ),but no significant difference between bacterial meningitis group and viral meningitis group (t =1.87,P ＞ 0.05 ).Conclusion PCT and CRP had clinical application value in the differential diagnosis of bacterial and viral meningitis.%目的 探讨血清降钙素原(PCT)、C-反应蛋白(CRP)对小儿急性细菌性及病毒性脑膜炎的诊断价值.方法 选择急性细菌性脑膜炎、病毒性脑膜炎患儿各30例,应用电化学发光免疫分析对其血清PCT 和CRP水平进行测定,并与30例健康儿童(对照组)进行比较.结果 细菌性脑膜炎组血清PCT显著高于对照组和病毒性脑膜炎组(t =7.67、5.67,均P＜0.01)；细菌性脑膜炎组、病毒性脑膜炎组血清CRP均高于对照组(t =2.52、2.47,均P＜0.05),但两组间差异无统计学意义(t=1.87,P＞0.05).结论 降钙素原、CRP对急性细菌性脑膜炎及病毒性脑膜炎的鉴别诊断具有临床应用价值.

Advanced characterization techniques in understanding the roles of nickel in enhancing strength and toughness of submerged arc welding high strength low alloy steel multiple pass welds in the as-welded condition

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Sham, Kin-Ling

Striving for higher strength along with higher toughness is a constant goal in material properties. Even though nickel is known as an effective alloying element in improving the resistance of a steel to impact fracture, it is not fully understood how nickel enhances toughness. It was the goal of this work to assist and further the understanding of how nickel enhanced toughness and maintained strength in particular for high strength low alloy (HSLA) steel submerged arc welding multiple pass welds in the as-welded condition. Using advanced analytical techniques such as electron backscatter diffraction, x-ray diffraction, electron microprobe, differential scanning calorimetry, and thermodynamic modeling software, the effect of nickel was studied with nickel varying from one to five wt. pct. in increments of one wt. pct. in a specific HSLA steel submerged arc welding multiple pass weldment. The test matrix of five different nickel compositions in the as-welded and stress-relieved condition was to meet the targeted mechanical properties with a yield strength greater than or equal to 85 ksi, a ultimate tensile strength greater than or equal to 105 ksi, and a nil ductility temperature less than or equal to -140 degrees F. Mechanical testing demonstrated that nickel content of three wt. pct and greater in the as-welded condition fulfilled the targeted mechanical properties. Therefore, one, three, and five wt. pct. nickel in the as-welded condition was further studied to determine the effect of nickel on primary solidification mode, nickel solute segregation, dendrite thickness, phase transformation temperatures, effective ferrite grain size, dislocation density and strain, grain misorientation distribution, and precipitates. From one to five wt. pct nickel content in the as-welded condition, the primary solidification was shown to change from primary delta-ferrite to primary austenite. The nickel partitioning coefficient increased and dendrite/cellular thickness was

Insulin resistance in porphyria cutanea tarda.

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Calcinaro, F; Basta, G; Lisi, P; Cruciani, C; Pietropaolo, M; Santeusanio, F; Falorni, A; Calafiore, R

1989-06-01

It has been reported that patients with porphyria cutanea tarda (PCT) develop carbohydrate (CHO) intolerance and manifest diabetes melitus (DM) more frequently than the normal population. In order to verify whether this is due to insulin resistance we studied 5 patients with PCT and 5 normal subjects matched for age, sex and weight. In all the patients an evaluation consisted of the glycemic curve and insulin response to an iv glucose tolerance test (IVGTT: 0.33 g/kg) as well as of an evaluation of the circulating monocyte insulin receptors. Blood samples were drawn in the basal state to measure plasma levels of NEFA, glycerol, and intermediate metabolites. The patients with PCT showed normal glucose tolerance which was obtained, however, at the expense of the elevated insulin levels: therefore a condition of insulin resistance was demonstrated in these subjects. An involvement of the lipid metabolism, observed by the raised levels of plasma NEFA and glycerol, was also evident. The insulin binding to circulating monocytes was reduced but not enough to justify the degree of insulin resistance observed. Therefore, it could be hypothesized, in agreement with similar studies, that a postreceptor defect is responsible for the insulin-resistance observed in patients with PCT and that the reduction of insulin receptors is determined by the down regulation in response to elevated insulinemic levels. An alteration of the porphyrin metabolism might be responsible for this disorder.

Mechanical and Thermal Properties of Pulsed Electric Current Sintered (PECS) Cu-Diamond Compacts

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Ritasalo, Riina; Kanerva, Ulla; Ge, Yanling; Hannula, Simo-Pekka

2014-04-01

In this work, dispersion strengthening of copper by diamonds is explored. In particular, the influence of 50- and 250-nm diamonds at contents of 3 and 6 vol. pct on the mechanical and thermal properties of pulsed electric current sintered (PECS) Cu composites is studied. The composite powders were prepared by mechanical alloying in argon atmosphere using a high-energy vibratory ball mill. The PECS compacts prepared had high density (>97 pct of T.D.) with quite evenly distributed diamonds. The effectiveness of dispersoids in increasing the microhardness was more pronounced at a smaller particle size and larger volume fraction, explained by Hall-Petch and Orowan strengthening models. The microhardness of Cu with 6 and 3 vol. pct nanodiamonds and pure sm-Cu (submicron-sized Cu) was 1.77, 1.46, and 1.02 GPa, respectively. In annealing experiments at 623 K to 873 K (350 °C to 600 °C), the composites with 6 vol. pct dispersoids retained their hardness better than those with less dispersoids or sm-Cu. The coefficient of thermal expansion was lowered when diamonds were added, being the lowest at about 14 × 10-6 K-1 between 473 K and 573 K (200 °C and 300 °C). Good bonding between the copper and diamond was qualitatively demonstrated by nanoindentation. In conclusion, high-quality Cu-diamond composites can be produced by PECS with improved strength and better thermal stability than for sm-Cu.

Chemistry and Mechanism of Interaction Between Molybdenite Concentrate and Sodium Chloride When Heated in the Presence of Oxygen

Science.gov (United States)

Aleksandrov, P. V.; Medvedev, A. S.; Imideev, V. A.; Moskovskikh, D. O.

2017-04-01

Roasting of molybdenum concentrates with sodium chloride has high potential and can be an alternative to oxidizing roasting and autoclave leaching; however, the chemistry and mechanism are poorly known. The chemical mechanism of the roasting process between molybdenite concentrate and sodium chloride in the presence of atmospheric oxygen is proposed. It is demonstrated that the process occurs through molybdenite oxidation, up to molybdenum trioxide, with subsequent formation of sodium polymolybdates and molybdenum dioxydichloride from molybdenum trioxide. It is found that the formation of water-soluble sodium polymolybdates from molybdenum trioxide stops over time due to passivation of sodium chloride surface by polymolybdates. It is proved experimentally that preliminary grinding of the mixture in a furnace charge leads to an increase in the polymolybdate fraction of the roasting products, which constitutes approximately 65 pct of molybdenum initially in the roasted mixture against 20 to 22 pct in a nonground mixture (or 75 to 77 pct against 30 to 33 pct of molybdenum in calcine). For the first time, the presence of the Na2S2O7 phase in the calcine was confirmed experimentally. The suggested mechanism gives possible explanations for the sharp increase of MoO2Cl2 formation within the temperature range of 673 K to 723 K (400 °C to 450 °C) that is based on the catalytic reaction of molybdenum dioxydichloride from the Na2S2O7 liquid phase as it runs in a melt.

A comparative study of perfusion CT and 99mTc-Hmpao spect measurement to assess cerebrovascular reserve capacity in patients with internal carotid artery occlusion

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Eicker S

2011-11-01

Full Text Available Abstract Background and purpose Patients with internal carotid artery (ICA occlusion can demonstrate impaired cerebral vascular reserve (CVR. The detection of CVR using single photon emission CT (SPECT is nowadays widely accepted as a predictor in the diagnostic pathway in patients considered for cerebral revascularization. Recently perfusion CT (PCT gained widely acceptance in stroke imaging The present study was aimed at comparing the results of perfusion CT (PCT and 99mTc-HMPAO SPECT with acetazolamide challenge in patients with ICA occlusion. Methods 13 patients were included in the prospective evaluation. Both PCT and 99mTc-HMPAO SPECT were performed before and after the administration of acetazolamide. In detail, regional cerebral blood flow (rCBF, regional cerebral blood volume (rCBV, adapted time to peak (Tmax and mean transit times (MTT were compared with SPECT data. Results 99mTc-HMPAO SPECT demonstrated an impairment of CVR in six patients. A preserved CVR was present in seven patients. All patients with impaired CVR proven by SPECT had a delayed MTT (mean +2.98 s and a delayed Tmax (mean + 5.9 s, (both p Conclusion The prospective study demonstrated a highly significant correlation of perfusion parameters as' detected by 99mTc-HMPAO SPECT and the Tmax as detected by PCT in patients with ICA occlusion. Therefore this easy-to-perform technique seems to be an adequate method for the evaluation of cerebral perfusion in patients with ICA occlusion.

Long-term impact of perfusion CT data after subarachnoid hemorrhage

Energy Technology Data Exchange (ETDEWEB)

Mathys, Christian; Martens, Daniel; Reichelt, Dorothea C.; Caspers, Julian; Aissa, Joel; May, Rebecca; Antoch, Gerald; Turowski, Bernd [University Duesseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Duesseldorf (Germany); Haenggi, Daniel [University Duesseldorf, Medical Faculty, Department of Neurosurgery, Duesseldorf (Germany)

2013-11-15

Dynamic perfusion computed tomography (PCT) has been established as a diagnostic instrument for the detection of vasospasm after subarachnoid hemorrhage (SAH). The purpose of this study was to assess the prognostic impact of PCT parameters after SAH on the long-term outcome of patients. Three hundred twelve patients were retrospectively interrogated with a questionnaire 23.06 {+-} 14.33 months after spontaneous subarachnoid hemorrhage. The modified Rankin scale (mRS) was determined, respectively. Scheduled PCT data sets from the first days after ictus were available for all patients. The maximum mean transit time over several examinations per hemisphere (MTT{sub PEAK}) values were significantly correlated (p {<=} 0.001, r = 0.422) with the clinical long-term outcome (mRS). Corresponding to our linear regression analysis, MTT{sub PEAK} is the second most important regressor (behind clinical severity of the initial hemorrhage) for the prediction of long-term mRS. An MTT{sub PEAK} threshold of 3.98 s (identified by receiver operating characteristic analysis, area under the curve = 0.75) predicted an unfavorable long-term outcome (mRS {>=} 2) with a sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of 67.3, 74.3, 84.5, 52.1, and 69.6 %, respectively. The presented data corroborate the relevance of PCT data for the clinical long-term outcome of SAH patients. By identification of patients who are at risk for a bad outcome and may need escalation of therapy, risk-benefit analysis is supported. (orig.)

Sol-gel synthesis of magnesium oxide-silicon dioxide glass compositions

Science.gov (United States)

Bansal, Narottam P.

1988-01-01

MgO-SiO2 glasses containing up to 15 mol pct MgO, which could not have been prepared by the conventional glass melting method due to the presence of stable liquid-liquid immiscibility, were synthesized by the sol-gel technique. Clear and transparent gels were obtained from the hydrolysis and polycondensation of silicon tetraethoxide (TEOS) and magnesium nitrate hexahydrate when the water/TEOS mole ratio was four or more. The gelling time decreased with increase in magnesium content, water/TEOS ratio, and reaction temperature. Magnesium nitrate hexahydrate crystallized out of the gels containing 15 and 20 mol pct MgO on slow drying. This problem was partially alleviated by drying the gels quickly at higher temperatures. Monolithic gel samples were prepared using glycerol as the drying control additive. The gels were subjected to various thermal treatments and characterized by several methods. No organic groups could be detected in the glasses after heat treatments to approx. 800 C, but trace amounts of hydroxyl groups were still present. No crystalline phase was found from X-ray diffraction in the gel samples to approx. 890 C. At higher temperatures, alpha quartz precipitated out as the crystalline phase in gels containing up to 10 mol pct MgO. The overall activation energy for gel formation in 10MgO-90SiO2 (mol pct) system for water/TEOS mole ratio of 7.5 was calculated to be 58.7 kJ/mol.

Effects of Heat Treatment on the Microstructure and Mechanical Properties of Low-Carbon Steel with Magnesium-Based Inclusions

Science.gov (United States)

Zhang, Jian; Feng, Pei-Hsien; Pan, Yan-Chi; Hwang, Weng-Sing; Su, Yen-Hao; Lu, Muh-Jung

2016-10-01

The effects of heat treatment on the microstructure and mechanical properties of Mg-containing (7 ppm), low-carbon commercial steel (SS400) were investigated. Twenty different heat treatment paths were performed using a Gleeble 1500 thermomechanical simulator. It was observed by using an optical microscope that as the cooling rate increased and holding temperature decreased, the volume fractions of pearlite, Widmanstätten ferrite, and grain boundary allotriomorphs ferrite fell, whereas that of acicular ferrite (AF) increased. Quantifying the fractions of AF and other phases by using electron backscatter diffraction shows that the heat treatment path with a cooling rate of 20 K/s and holding temperature of 723 K (450 °C) induced the highest volume fraction (44 pct) of AF. As such, the toughness of the sample was increased 12.4 times compared with that observed in the sample containing 4 pct AF. Typical inclusions were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy. The results showed that the magnesium-based complex inclusions could act as nucleation sites of AF. Inclusions with a size of about 5 μm can serve as heterogeneous nucleation sites for AF. Mg-containing SS400 steel also has excellent hot-ductility in the temperature range of 973 K to 1273 K (700 °C to 1000 °C), and the minimum percentage reduction in area (R.A pct) value of around 63 pct at 1073 K (800 °C).

Polychlorinated terphenyl patterns and levels in selected marine mammals and a river fish from different continents.

Science.gov (United States)

Rosenfelder, Natalie; Vetter, Walter

2014-01-01

Polychlorinated terphenyls (PCTs) are a class of persistent organic pollutants which have been used from the 1920s to the 1980s for similar purposes as polychlorinated biphenyls (PCBs). Comparably little data was available on the PCT distribution in the environment mainly due to analytical difficulties in their determination. By means of a calculation algorithm recently developed we now studied the PCT pattern in individual marine mammal samples and one fish sample from different continents. Altogether, 97 PCTs were detected in eight samples and twelve to 66 tetra- to nonachloroterphenyl (tetra- to nonaCT) congeners were detected in individual samples. PCTs were present in all marine mammal samples which originated from four continents, but the PCT pattern was varied. TetraCTs were dominant in the sample from Africa, Australia, Spitsbergen (European Arctic) and in a sample from the Baltic Sea, heptaCTs in samples from the North Sea and octaCTs in a sample from Iceland. The abundance of sumPCTs relative to PCB 153, estimated from the GC/ECNI-MS response corrected for the degree of chlorination, ranged from 0.9 to 8.8%, corresponding with ~0.22-2.2% of the total PCB content. The highest PCT level detected was 980 mg/kg lipid in a harbour seal from the North Sea, Germany. The results from this study indicated that samples from certain areas, e.g. the North Sea may still be polluted with PCTs. © 2013.

Acute Effects of Two Different Resistance Circuit Training Protocols on Performance and Perceived Exertion in Semiprofessional Basketball Players.

Science.gov (United States)

Freitas, Tomás T; Calleja-González, Julio; Alarcón, Francisco; Alcaraz, Pedro E

2016-02-01

This study aimed to investigate the acute effects of two different resistance circuit training protocols on basketball players' physical and technical performance and rating of perceived exertion (RPE). In a repeated-measures, crossover experimental design, 9 semiprofessional basketball players performed a Power Circuit Training (PCT; 45% 1RM) and a High-Resistance Circuit Training (HRC; 6RM), on consecutive weeks. Vertical and horizontal jump performance, 3-points shooting accuracy, repeated-sprint ability (RSA), agility, and upper body power output were measured before and after training. The RPE was assessed 20 minutes after resistance training. One-way repeated-measures analysis of variance showed performance decrements in vertical jump height and peak power, horizontal jump distance, 3-points percentage, bench-press power output, RSA total and ideal time, and agility T-Test at total time following HRC, but not PCT (p ≤ 0.05). The RPE was higher in HRC compared with PCT. The results of this study indicated that HRC was perceived as being harder and produced higher fatigue levels, which in turn lowered acute performance. However, low-to-moderate intensity loads did not negatively affect performance. Thus, completing a PCT session may be the most appropriate option before a practice or game as it avoids acute-resistance-training-induced performance decrements. However, if the objective of the basketball session is to develop or perfect technical skills during fatiguing conditions, HRC may be the more suitable option.

Adaptive statistical iterative reconstruction improves image quality without affecting perfusion CT quantitation in primary colorectal cancer

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D. Prezzi

Full Text Available Objectives: To determine the effect of Adaptive Statistical Iterative Reconstruction (ASIR on perfusion CT (pCT parameter quantitation and image quality in primary colorectal cancer. Methods: Prospective observational study. Following institutional review board approval and informed consent, 32 patients with colorectal adenocarcinoma underwent pCT (100 kV, 150 mA, 120 s acquisition, axial mode. Tumour regional blood flow (BF, blood volume (BV, mean transit time (MTT and permeability surface area product (PS were determined using identical regions-of-interests for ASIR percentages of 0%, 20%, 40%, 60%, 80% and 100%. Image noise, contrast-to-noise ratio (CNR and pCT parameters were assessed across ASIR percentages. Coefficients of variation (CV, repeated measures analysis of variance (rANOVA and Spearman’ rank order correlation were performed with statistical significance at 5%. Results: With increasing ASIR percentages, image noise decreased by 33% while CNR increased by 61%; peak tumour CNR was greater than 1.5 with 60% ASIR and above. Mean BF, BV, MTT and PS differed by less than 1.8%, 2.9%, 2.5% and 2.6% across ASIR percentages. CV were 4.9%, 4.2%, 3.3% and 7.9%; rANOVA P values: 0.85, 0.62, 0.02 and 0.81 respectively. Conclusions: ASIR improves image noise and CNR without altering pCT parameters substantially. Keywords: Perfusion imaging, Multidetector computed tomography, Colorectal neoplasms, Computer-assisted image processing, Radiation dosage

Predicting CT Image From MRI Data Through Feature Matching With Learned Nonlinear Local Descriptors.

Science.gov (United States)

Yang, Wei; Zhong, Liming; Chen, Yang; Lin, Liyan; Lu, Zhentai; Liu, Shupeng; Wu, Yao; Feng, Qianjin; Chen, Wufan

2018-04-01

Attenuation correction for positron-emission tomography (PET)/magnetic resonance (MR) hybrid imaging systems and dose planning for MR-based radiation therapy remain challenging due to insufficient high-energy photon attenuation information. We present a novel approach that uses the learned nonlinear local descriptors and feature matching to predict pseudo computed tomography (pCT) images from T1-weighted and T2-weighted magnetic resonance imaging (MRI) data. The nonlinear local descriptors are obtained by projecting the linear descriptors into the nonlinear high-dimensional space using an explicit feature map and low-rank approximation with supervised manifold regularization. The nearest neighbors of each local descriptor in the input MR images are searched in a constrained spatial range of the MR images among the training dataset. Then the pCT patches are estimated through k-nearest neighbor regression. The proposed method for pCT prediction is quantitatively analyzed on a dataset consisting of paired brain MRI and CT images from 13 subjects. Our method generates pCT images with a mean absolute error (MAE) of 75.25 ± 18.05 Hounsfield units, a peak signal-to-noise ratio of 30.87 ± 1.15 dB, a relative MAE of 1.56 ± 0.5% in PET attenuation correction, and a dose relative structure volume difference of 0.055 ± 0.107% in , as compared with true CT. The experimental results also show that our method outperforms four state-of-the-art methods.

Clinical evaluation of C-reactive protein and procalcitonin for the early detection of postoperative complications after laparoscopic sleeve gastrectomy.

Science.gov (United States)

Frask, Agata; Orłowski, Michał; Dowgiałło-Wnukiewicz, Natalia; Lech, Paweł; Gajewski, Krzysztof; Michalik, Maciej

2017-06-01

Among the most common early complications after bariatric surgery are anastomosis leak and bleeding. In order to react quickly and perform accurate treatment before the clinical signs appear, early predictors should be found. In the study C-reactive protein (CRP) and procalcitonin (PCT) levels were investigated. Characterized by a relatively short half-life, they can predict surgical complications. To develop and implement certain standards for early detection of complications. The study involved 319 adults who underwent laparoscopic sleeve gastrectomy (LSG) as a surgical intervention for morbid obesity at the Department of General Surgery of Ceynowa Hospital in Wejherowo. Every patient had CRP and PCT levels measured before the surgery and on the 1 st and 2 nd postoperative day (POD). Early postoperative complications occurred in 19 (5.96%) patients. Septic and non-septic complications occurred in 3 and 16 patients respectively. Among the patients with septic postoperative complications CRP level increased significantly on the 2 nd POD compared to the remainder (p = 0.0221). Among the patients with non-septic postoperative complications CRP level increased significantly on the 1 st and 2 nd POD compared to the remainder. Among the patients with septic and non-septic postoperative complications PCT level increased significantly on the 2 nd POD compared to the remainder. The CRP and PCT level are supposed to be relevant diagnostic markers to predict non-septic and septic complications after LSG.

Mechanical Behavior of Three-Dimensional Braided Nickel-Based Superalloys Synthesized via Pack Cementation

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Lippitz, Nicolas; Erdeniz, Dinc; Sharp, Keith W.; Dunand, David C.

2018-03-01

Braided tubes of Ni-based superalloys are fabricated via three-dimensional (3-D) braiding of ductile Ni-20Cr (wt pct) wires followed by post-textile gas-phase alloying with Al and Ti to create, after homogenization and aging, γ/ γ' strengthened lightweight, porous structures. Tensile tests reveal an increase in strength by 100 MPa compared to as-braided Ni-20Cr (wt pct). An interrupted tensile test, combined with X-ray tomographic scans between each step, sheds light on the failure behavior of the braided superalloy tubes.

Syntactic error modeling and scoring normalization in speech recognition: Error modeling and scoring normalization in the speech recognition task for adult literacy training

Science.gov (United States)

Olorenshaw, Lex; Trawick, David

1991-01-01

The purpose was to develop a speech recognition system to be able to detect speech which is pronounced incorrectly, given that the text of the spoken speech is known to the recognizer. Better mechanisms are provided for using speech recognition in a literacy tutor application. Using a combination of scoring normalization techniques and cheater-mode decoding, a reasonable acceptance/rejection threshold was provided. In continuous speech, the system was tested to be able to provide above 80 pct. correct acceptance of words, while correctly rejecting over 80 pct. of incorrectly pronounced words.

Initial Stages of Recrystallization in Aluminum of Commercial Purity

DEFF Research Database (Denmark)

Hansen, Niels; Bay, Bent

1979-01-01

In commercial aluminum with a purity of 99.4 pct, the formation and growth of recrystallization nuclei were studied by techniques such asin-situ annealing in a high voltage electron microscope, transmission electron microscopy and light microscopy. Sample parameters were the initial grain size (370...... by the FeAl3 particles present in the commercial aluminum as impurities. The nucleation temperatures determined by high voltage electron microscopy and transmission electron microscopy decrease markedly when the initial grain size is decreased both after 50 and 90 pct cold rolling; a less pronounced...

Volumetric evaluation of dual-energy perfusion CT by the presence of intrapulmonary clots using a 64-slice dual-source CT

Energy Technology Data Exchange (ETDEWEB)

Okada, Munemasa; Nakashima, Yoshiteru; Kunihiro, Yoshie; Nakao, Sei; Matsunaga, Naofumi [Dept. of Radiology, Yamaguchi Univ. Graduate School of Medicine, Yamaguchi (Japan)], e-mail: radokada@yamaguchi-u.ac.jp; Morikage, Noriyasu [Medical Bioregulation Dept. of Organ Regulatory Surgery, Yamaguchi Univ. Graduate School of Medicine, Yamaguchi (Japan); Sano, Yuichi [Dept. of Radiology, Yamaguchi Univ. Hospital, Yamaguchi (Japan); Suga, Kazuyoshi [Dept. of Radiology, St Hills Hospital, Yamaguchi (Japan)

2013-07-15

Background: Dual-energy perfusion CT (DE{sub p}CT) directly represents the iodine distribution in lung parenchyma and low perfusion areas caused by intrapulmonary clots (IPCs) are visualized as low attenuation areas. Purpose: To evaluate if volumetric evaluation of DE{sub p}CT can be used as a predictor of right heart strain by the presence of IPCs. Material and Methods: One hundred and ninety-six patients suspected of having acute pulmonary embolism (PE) underwent DE{sub p}CT using a 64-slice dual-source CT. DE{sub p}CT images were three-dimensionally reconstructed with four threshold ranges: 1-120 HU (V{sub 120}), 1-15 HU (V{sub 15}), 1-10 HU (V{sub 10}), and 1-5 HU (V{sub 5}). Each relative ratio per V{sub 120} was expressed as the %V{sub 15}, %V{sub 10}, and %V{sub 5}. Volumetric data-sets were compared with D-dimer, pulmonary arterial (PA) pressure, right ventricular (RV) diameter, RV/left ventricular (RV/LV) diameter ratio, PA diameter, and PA/aorta (PA/Ao) diameter ratio. The areas under the ROC curves (AUCs) were examined for their relationship to the presence of IPCs. This study was approved by the local ethics committee. Results: PA pressure and D-dimer were significantly higher in the patients who had IPCs. In the patients with IPCs, V{sub 15}, V{sub 10}, V{sub 5}, %V{sub 15}, %V{sub 10}, and %V{sub 5} were also significantly higher than those without IPC (P = 0.001). %V{sub 5} had a better correlation with D-dimer (r = 0.30, P < 0.001) and RV/LV diameter ratio (r = 0.27, P < 0.001), and showed a higher AUC (0.73) than the other CT measurements. Conclusion: The volumetric evaluation by DE{sub p}CT had a correlation with D-dimer and RV/LV diameter ratio, and the relative ratio of volumetric CT measurements with a lower attenuation threshold might be recommended for the analysis of acute PE.

Geomorphometric analysis of selected Martian craters using polar coordinate transformation

Science.gov (United States)

Magyar, Zoltán; Koma, Zsófia; Székely, Balázs

2016-04-01

Centrally symmetric landform elements are very common features on the surface of the planet Mars. The most conspicuous ones of them are the impact craters of various size. However, a closer look on these features reveals that they show often asymmetric patterns as well. These are partially related to the geometry of the trajectory of the impacting body, but sometimes it is a result of surface processes (e.g., freeze/thaw cycles, mass movements). Geomorphometric studies have already been carried out to reveal these pecularities. Our approach, the application of polar coordinate transformation (PCT) very sensitively enhances the non-radial and non-circular shapes. We used digital terrain models (DTMs) derived from the ESA Mars Express HRSC imagery. The original DTM or its derivatives (e.g. slope angle or aspect) are PCT transformed. We analyzed the craters inter alia with scattergrams in polar coordinates. The resulting point cloud can be used directly for the analysis, but in some cases an interpolation should be applied to enhance certain non-circular features (especially in case of smaller craters). Visual inspection of the crater slopes, coloured by the aspect, reveals smaller features. Some of them are processing artefacts, but many of them are related to local undulations in the topography or indications of mass movements. In many cases the undulations of the crater rim are due to erosional processes. The drawbacks of the technology are related to the uneven resolution of the projected image: features in the crater centre should be left out from the analysis because PCT has a low resolution around the projection center. Furthermore, the success of the PCT depends on the correct definition of the projection centre: erroneously centered images are not suitable for analysis. The PCT transformed images are also suitable for radial averaging and calculation of standard deviations, resulting in typical, comparable craters shapes. These studies may lead to a deeper

[Ability of procalcitonin to predict bacteremia in patients with community acquired pneumonia].

Science.gov (United States)

Julián-Jiménez, Agustín; Timón Zapata, Jesús; Laserna Mendieta, Emilio José; Parejo Miguez, Raquel; Flores Chacartegui, Manuel; Gallardo Schall, Pablo

2014-04-07

To analyze the usefulness and ability of procalcitonin (PCT) to predict the presence of bacteremia in patients with community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae (S. pneumoniae) or other bacteria. This is an observational, prospective and descriptive study involving patients who were diagnosed with CAP in our Emergency Department. Data collected included socio-demographic and comorbidity variables, Charlson index, stage in the Pneumonia Severity Index and criteria of severe NAC, microbiologic studies and biomarker determinations (PCT and C reactive protein). The follow-up was carried out during 30 days to calculate the predictive power and the diagnostic performance for bacteremia caused or not by S. pneumoniae. Four hundred and seventy-four patients were finally included in the study. Blood cultures were positive in 85 individuals (17.9%) and S. pneumoniae was identified as the responsible pathogen in 75 of them (88.4%) (in 5 cases together with another agent). The area under the Receiver Operating Characteristic curve for PCT to predict bacteremia (caused by S. pneumoniae or not) was 0.988 (95% confidence interval 0.908-0.995; P98% and>10, respectively. The most frequently isolated serotypes of S. pneumoniae were 19A, 7F, 1 and 3. The highest mean levels of PCT were found in serotypes 7F, 19A, 3 and 1, which showed statistically significant differences with regard to the others serotypes considered (P=.008). Serotypes associated with the highest percentage of severe sepsis-septic shock, 30-days mortality and multi-lobe or bilateral affection were 3, 1 and 19A; 1, 3 and 19A; and 3, 19A and 6A, respectively. PCT had a remarkable diagnostic ability to discard or suspect bacteremia and to guide the etiology of CAP caused by S. pneumoniae. Serotypes 1, 3, 19A and 7F showed greater frequency, systemic inflammatory response and clinical severity. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Investigating CT to CBCT image registration for head and neck proton therapy as a tool for daily dose recalculation

Energy Technology Data Exchange (ETDEWEB)

Landry, Guillaume, E-mail: g.landry@lmu.de [Department of Medical Physics, Ludwig-Maximilians-University, Munich D85748, Germany and Department of Radiation Oncology, Ludwig-Maximilians-University, Munich D81377 (Germany); Nijhuis, Reinoud; Thieke, Christian; Reiner, Michael; Ganswindt, Ute; Belka, Claus [Department of Radiation Oncology, Ludwig-Maximilians-University, Munich D81377 (Germany); Dedes, George; Handrack, Josefine; Parodi, Katia [Department of Medical Physics, Ludwig-Maximilians-University, Munich D85748 (Germany); Janssens, Guillaume; Orban de Xivry, Jonathan [ICTEAM, Université Catholique de Louvain, Louvain-La-Neuve B1348 (Belgium); Kamp, Florian; Wilkens, Jan J. [Department of Radiation Oncology, Technische Universität München, Klinikum rechts der Isar, Munich D81675, Germany and Physik-Department, Technische Universität München, Garching D85748 (Germany); Paganelli, Chiara; Riboldi, Marco; Baroni, Guido [Dipartimento di Elettronica Informazione e Bioingegneria, Politecnico di Milano, Milan 20133 (Italy)

2015-03-15

Purpose: Intensity modulated proton therapy (IMPT) of head and neck (H and N) cancer patients may be improved by plan adaptation. The decision to adapt the treatment plan based on a dose recalculation on the current anatomy requires a diagnostic quality computed tomography (CT) scan of the patient. As gantry-mounted cone beam CT (CBCT) scanners are currently being offered by vendors, they may offer daily or weekly updates of patient anatomy. CBCT image quality may not be sufficient for accurate proton dose calculation and it is likely necessary to perform CBCT CT number correction. In this work, the authors investigated deformable image registration (DIR) of the planning CT (pCT) to the CBCT to generate a virtual CT (vCT) to be used for proton dose recalculation. Methods: Datasets of six H and N cancer patients undergoing photon intensity modulated radiation therapy were used in this study to validate the vCT approach. Each dataset contained a CBCT acquired within 3 days of a replanning CT (rpCT), in addition to a pCT. The pCT and rpCT were delineated by a physician. A Morphons algorithm was employed in this work to perform DIR of the pCT to CBCT following a rigid registration of the two images. The contours from the pCT were deformed using the vector field resulting from DIR to yield a contoured vCT. The DIR accuracy was evaluated with a scale invariant feature transform (SIFT) algorithm comparing automatically identified matching features between vCT and CBCT. The rpCT was used as reference for evaluation of the vCT. The vCT and rpCT CT numbers were converted to stopping power ratio and the water equivalent thickness (WET) was calculated. IMPT dose distributions from treatment plans optimized on the pCT were recalculated with a Monte Carlo algorithm on the rpCT and vCT for comparison in terms of gamma index, dose volume histogram (DVH) statistics as well as proton range. The DIR generated contours on the vCT were compared to physician-drawn contours on the rp

The effect of TiB2 reinforcement on the mechanical properties of an Al-Cu-Li alloy-based metal-matrix composite

Science.gov (United States)

1991-01-01

The addition of ceramic particles to aluminum based alloys can substantially improve mechanical properties, especially Young's modulus and room and elevated temperature strengths. However, these improvements typically occur at the expense of tensile ductility. The mechanical properties are evaluated to a metal matrix composite (MMC) consisting of an ultrahigh strength aluminum lithium alloy, Weldalite (tm) 049, reinforced with TiB2 particles produced by an in situ precipitation technique called the XD (tm) process. The results are compared to the behavior of a nonreinforced Weldalite 049 variant. It is shown that both 049 and 049-TiB2 show very attractive warm temperature properties e.g., 625 MPa yield strength at 150 C after 100 h at temperature. Weldalite 049 reinforced with a nominal 4 v pct. TiB2 shows an approx. 8 pct. increase in modulus and a good combination of strength (529 MPa UTS) and ductility (6.5 pct.) in the T3 temper. And the high ductility of Weldalite 049 in the naturally aged and underaged tempers makes the alloy a good, high strength matrix for ceramic reinforcement.

Circulating cytokines and procalcitonin in acute Q fever granulomatous hepatitis with poor response to antibiotic and short-course steroid therapy: a case report

Directory of Open Access Journals (Sweden)

Chang Lin-Li

2010-07-01

Full Text Available Abstract Background Q fever is a zoonosis distributed worldwide that is caused by Coxiella burnetii infection and the defervescence usually occurs within few days of appropriate antibiotic therapy. Whether the changes of cytokine levels are associated with acute Q fever with persistent fever despite antibiotic therapy had not been investigated before. Case Presentation We report a rare case of acute Q fever granulomatous hepatitis remained pyrexia despite several antibiotic therapy and 6-day course of oral prednisolone. During the 18-month follow-up, the investigation of the serum cytokines profile and procalcitonin (PCT revealed that initially elevated levels of interleukin-2 (IL-2, IL-8, IL-10, and PCT decreased gradually, but the IL-6 remained in low titer. No evidence of chronic Q fever was identified by examinations of serum antibodies against C. burnetii and echocardiography. Conclusions The changes of cytokine levels may be associated with acute Q fever with poor response to treatment and PCT may be an indicator for monitoring the response to treatment.

Microstructure and Properties of Fe3Al-Fe3AlC x Composite Prepared by Reactive Liquid Processing

Science.gov (United States)

Verona, Maria Nalu; Setti, Dalmarino; Paredes, Ramón Sigifredo Cortés

2018-04-01

A Fe3Al-Fe3AlC x composite was prepared using reactive liquid processing (RLP) through controlled mixture of carbon steel and aluminum in the liquid state. The microstructure and phases of the composite were assessed using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, optical microscopy, and differential scanning calorimetry. In addition, the density, hardness, microhardness, and elastic modulus were evaluated. The Fe3Al-Fe3AlC x composite consisted of 65 vol pct Fe3Al and 35 vol pct Fe3AlC x ( κ). The κ phase contained 10.62 at. pct C, resulting in the stoichiometry Fe3AlC0.475. The elastic modulus of the Fe3Al-Fe3AlC0.475 composite followed the rule of mixtures. The RLP technique was shown to be capable of producing Fe3Al-Fe3AlC0.475 with a microstructure and properties similar to those achieved using other processing techniques reported in the literature.

Diagnostic Accuracy of Platelet Count and Platelet Indices in Noninvasive Assessment of Fibrosis in Nonalcoholic Fatty Liver Disease Patients

Directory of Open Access Journals (Sweden)

Tamara Milovanovic Alempijevic

2017-01-01

Full Text Available Objective. Keeping in mind the rising prevalence of nonalcoholic fatty liver disease (NAFLD and the need to establish noninvasive tests for its detection, the aim of our study was to investigate whether platelet count (PC, mean platelet volume (MPV, and platelet distribution width (PDW can predict the presence of liver fibrosis in this group of patients. Methods. In 98 patients with NAFLD and 60 healthy volunteers, complete blood counts with automated differential counts were performed and values of PC, PDW, MPV, and PCT were analyzed. Results. Patients with NAFLD had lower PC and higher MPV, PCT, and PDW compared to the controls (P < 0.05. When NAFLD group was stratified according to severity of liver fibrosis, there was a statistically significant difference in the average values of PDW and PC between the groups (P < 0.05. Conclusion. Patients with NAFLD have significantly higher values of PCT, PDW, and MPV when compared to the healthy controls. Further studies are needed to establish their potential use for prediction of the degree of liver steatosis and fibrosis in NAFLD patients.

Hot Corrosion Behavior of Ti-48Al and Ti-48Al-2Cr Intermetallic Alloys Produced by Electric Current Activated Sintering

Science.gov (United States)

Garip, Y.; Ozdemir, O.

2018-06-01

In this study, Ti-48Al and Ti-48Al-2Cr (at. pct) intermetallic alloys were produced by electric current activated sintering (ECAS). In order to characterize the phase formation and microstructures of these alloys, scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD) analysis were used. The XRD result shows that the intermetallic alloys are composed of γ-TiAl and α 2-Ti3Al phases. The microstructure is dense with a low amount of porosity. The hot corrosion behavior of intermetallic alloys was carried out in a salt mixture of 25 wt pct K2SO4 and 75 wt pct Na2SO4 at 700 °C for 180 hours. The morphology of corroded surfaces was observed by SEM-EDS and XRD. Corrosion phases were identified as TiO2 and Al2O3. Well-adhering oxide scale was detected on the corroded sample surface at the end of 180 hours, and no spallation was observed. In addition, a parabolic curve was obtained at the weight change rate vs time.

Effect of oxygen incorporation on the vibrational properties of Al0.2Ga0.3In0.5P:Be films

International Nuclear Information System (INIS)

Soubervielle-Montalvo, C.; Vital-Ochoa, O.; Anda, F. de; Vazquez-Cortes, D.; Rodriguez, A.G.; Melendez-Lira, M.; Mendez-Garcia, V.H.

2011-01-01

The vibrational properties of Al 0.2 Ga 0.3 In 0.5 P:Be films grown on (100) GaAs substrates by solid source molecular beam epitaxy varying the phosphorous cracking-zone temperature (PCT) were studied by Raman spectroscopy. The Raman-intensity ratio between the allowed longitudinal optical and the forbidden transverse optical (TO) phonons, and the full width at half maximum of their Lorentzian fits were used to characterize the crystalline quality of the films. The Raman spectra from the samples show changes in the shape and intensity of phonon resonances depending on the PCT variation, indicating that the disorder in the lattice increases with PCT. The increasing disorder is related to the inclusion of oxygen, which act as a non-intentional perturbing impurity in the lattice. In addition, a vibrational mode located at 598 cm -1 related to a forbidden InP-like TO phonon resonance was correlated with oxygen-induced disorder. Photoluminescence at room temperature shows that the high inclusion of oxygen also deteriorates the optical properties of the samples, by introducing non-radiative recombination centers.

Oxidative Pressure Leaching of Silver from Flotation Concentrates with Ammonium Thiocyanate Solution

Science.gov (United States)

Yang, Sheng-Hai; Yang, Jian-Guang; Liu, Wei; Chen, Geng-Tao; Tang, Mo-Tang; Qiu, Guan-Zhou

2010-02-01

The thermodynamics and technologies of the selective pressure leaching of silver from flotation concentrates were investigated in an ammonium thiocyanate medium. Thermodynamic analyses, which include silver solubility in NH4SCN solution and Eh-pH diagrams of the Me-MeS-NH4SCN-H2O system at 25 °C, were discussed. The effects of several factors, such as temperature, leaching time, oxidant, pH value, flotation concentrates concentration, surfactant concentration, and so on, on the extraction percentages of silver and zinc were investigated. The following optimal leaching conditions were obtained: NH4SCN concentration 1.5 M, lignin concentration 0.5 g/L, Fe3+ concentration 2 g/L, flotation concentrates addition 200 g/L, and oxygen pressure 1.2 MPa at 130 °C for 3 hours. Under these optimum conditions, the average extraction percentage of silver exceeded 94 pct, whereas the average extraction percentage of zinc was less than 3 pct. Only 7 pct of ammonium thiocyanate was consumed after 4 cycles, which indicated that ammonium thiocyanate hardly was oxidized under these oxidative pressure leaching conditions.

High Accuracy Beam Current Monitor System for CEBAF'S Experimental Hall A

International Nuclear Information System (INIS)

J. Denard; A. Saha; G. Lavessiere

2001-01-01

CEBAF accelerator delivers continuous wave (CW) electron beams to three experimental Halls. In Hall A, all experiments require continuous, non-invasive current measurements and a few experiments require an absolute accuracy of 0.2 % in the current range from 1 to 180 (micro)A. A Parametric Current Transformer (PCT), manufactured by Bergoz, has an accurate and stable sensitivity of 4 (micro)A/V but its offset drifts at the muA level over time preclude its direct use for continuous measurements. Two cavity monitors are calibrated against the PCT with at least 50 (micro)A of beam current. The calibration procedure suppresses the error due to PCT's offset drifts by turning the beam on and off, which is invasive to the experiment. One of the goals of the system is to minimize the calibration time without compromising the measurement's accuracy. The linearity of the cavity monitors is a critical parameter for transferring the accurate calibration done at high currents over the whole dynamic range. The method for measuring accurately the linearity is described

Hot Corrosion Behavior of Ti-48Al and Ti-48Al-2Cr Intermetallic Alloys Produced by Electric Current Activated Sintering

Science.gov (United States)

Garip, Y.; Ozdemir, O.

2018-03-01

In this study, Ti-48Al and Ti-48Al-2Cr (at. pct) intermetallic alloys were produced by electric current activated sintering (ECAS). In order to characterize the phase formation and microstructures of these alloys, scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD) analysis were used. The XRD result shows that the intermetallic alloys are composed of γ-TiAl and α 2-Ti3Al phases. The microstructure is dense with a low amount of porosity. The hot corrosion behavior of intermetallic alloys was carried out in a salt mixture of 25 wt pct K2SO4 and 75 wt pct Na2SO4 at 700 °C for 180 hours. The morphology of corroded surfaces was observed by SEM-EDS and XRD. Corrosion phases were identified as TiO2 and Al2O3. Well-adhering oxide scale was detected on the corroded sample surface at the end of 180 hours, and no spallation was observed. In addition, a parabolic curve was obtained at the weight change rate vs time.

Effect of Particle Size on Thermal Conductivity of Nanofluid

Science.gov (United States)

Chopkar, M.; Sudarshan, S.; Das, P. K.; Manna, I.

2008-07-01

Nanofluids, containing nanometric metallic or oxide particles, exhibit extraordinarily high thermal conductivity. It is reported that the identity (composition), amount (volume percent), size, and shape of nanoparticles largely determine the extent of this enhancement. In the present study, we have experimentally investigated the impact of Al2Cu and Ag2Al nanoparticle size and volume fraction on the effective thermal conductivity of water and ethylene glycol based nanofluid prepared by a two-stage process comprising mechanical alloying of appropriate Al-Cu and Al-Ag elemental powder blend followed by dispersing these nanoparticles (1 to 2 vol pct) in water and ethylene glycol with different particle sizes. The thermal conductivity ratio of nanofluid, measured using an indigenously developed thermal comparator device, shows a significant increase of up to 100 pct with only 1.5 vol pct nanoparticles of 30- to 40-nm average diameter. Furthermore, an analytical model shows that the interfacial layer significantly influences the effective thermal conductivity ratio of nanofluid for the comparable amount of nanoparticles.

Survey research report by the hydrogen occluding alloy utilization development committee; Suiso kyuzo gokin riyo kaihatsu iinkai chosa kenkyu hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1985-03-01

This report summarizes the FY 1984 survey research results, issued by the hydrogen occluding alloy utilization development committee. The basic property subcommittee is responsible for collecting published data related to the basic properties of metal halides as much as possible, and pigeonholing them to have the data which can contribute to development of the new alloys for basic researches and engineering applications of hydrogen occluding alloys. The subcommittee members have collected these data. The common theme subcommittee has planned to collect the P-C-T diagrams of the hydrogen occluding alloys and new alloys as much as possible, for the designs, development, production and system designs of the hydrogen occluding alloys. The P-C-T diagrams have been collected for a total of 340 types of alloys, which fall into the broad categories of Mg-based, TiFe-based, TiMn-based, other Ti-based, rare-earth-based, Zr-based, Ca-based and others. The analytical methods have been also investigated while collecting P-C-T diagrams. (NEDO)

Analysis on Experimental Investigation and Mathematical Modeling of Incompressible Flow Through Ceramic Foam Filters

Science.gov (United States)

Akbarnejad, Shahin; Jonsson, Lage Tord Ingemar; Kennedy, Mark William; Aune, Ragnhild Elizabeth; Jönsson, Pӓr Göran

2016-08-01

This paper presents experimental results of pressure drop measurements on 30, 50, and 80 pores per inch (PPI) commercial alumina ceramic foam filters (CFF) and compares the obtained pressure drop profiles to numerically modeled values. In addition, it is aimed at investigating the adequacy of the mathematical correlations used in the analytical and the computational fluid dynamics (CFD) simulations. It is shown that the widely used correlations for predicting pressure drop in porous media continuously under-predict the experimentally obtained pressure drop profiles. For analytical predictions, the negative deviations from the experimentally obtained pressure drop using the unmodified Ergun and Dietrich equations could be as high as 95 and 74 pct, respectively. For the CFD predictions, the deviation to experimental results is in the range of 84.3 to 88.5 pct depending on filter PPI. Better results can be achieved by applying the Forchheimer second-order drag term instead of the Brinkman-Forchheimer drag term. Thus, the final deviation of the CFD model estimates lie in the range of 0.3 to 5.5 pct compared to the measured values.

Use of Hot Rolling for Generating Low Deviation Twins and a Disconnected Random Boundary Network in Inconel 600 Alloy

Science.gov (United States)

Sahu, Sandeep; Yadav, Prabhat Chand; Shekhar, Shashank

2018-02-01

In this investigation, Inconel 600 alloy was thermomechanically processed to different strains via hot rolling followed by a short-time annealing treatment to determine an appropriate thermomechanical process to achieve a high fraction of low-Σ CSL boundaries. Experimental results demonstrate that a certain level of deformation is necessary to obtain effective "grain boundary engineering"; i.e., the deformation must be sufficiently high to provide the required driving force for postdeformation static recrystallization, yet it should be low enough to retain a large fraction of original twin boundaries. Samples processed in such a fashion exhibited 77 pct length fraction of low-Σ CSL boundaries, a dominant fraction of which was from Σ3 ( 64 pct), the latter with very low deviation from its theoretical misorientation. The application of hot rolling also resulted in a very low fraction of Σ1 ( 1 pct) boundaries, as desired. The process also leads to so-called "triple junction engineering" with the generation of special triple junctions, which are very effective in disrupting the connectivity of the random grain boundary network.

Analytical evaluation of the signal and noise propagation in x-ray differential phase-contrast computed tomography

International Nuclear Information System (INIS)

Raupach, Rainer; Flohr, Thomas G

2011-01-01

We analyze the signal and noise propagation of differential phase-contrast computed tomography (PCT) compared with conventional attenuation-based computed tomography (CT) from a theoretical point of view. This work focuses on grating-based differential phase-contrast imaging. A mathematical framework is derived that is able to analytically predict the relative performance of both imaging techniques in the sense of the relative contrast-to-noise ratio for the contrast of any two materials. Two fundamentally different properties of PCT compared with CT are identified. First, the noise power spectra show qualitatively different characteristics implying a resolution-dependent performance ratio. The break-even point is derived analytically as a function of system parameters such as geometry and visibility. A superior performance of PCT compared with CT can only be achieved at a sufficiently high spatial resolution. Second, due to periodicity of phase information which is non-ambiguous only in a bounded interval statistical phase wrapping can occur. This effect causes a collapse of information propagation for low signals which limits the applicability of phase-contrast imaging at low dose.

Feasibility of MR-only proton dose calculations for prostate cancer radiotherapy using a commercial pseudo-CT generation method

Science.gov (United States)

Maspero, Matteo; van den Berg, Cornelis A. T.; Landry, Guillaume; Belka, Claus; Parodi, Katia; Seevinck, Peter R.; Raaymakers, Bas W.; Kurz, Christopher

2017-12-01

A magnetic resonance (MR)-only radiotherapy workflow can reduce cost, radiation exposure and uncertainties introduced by CT-MRI registration. A crucial prerequisite is generating the so called pseudo-CT (pCT) images for accurate dose calculation and planning. Many pCT generation methods have been proposed in the scope of photon radiotherapy. This work aims at verifying for the first time whether a commercially available photon-oriented pCT generation method can be employed for accurate intensity-modulated proton therapy (IMPT) dose calculation. A retrospective study was conducted on ten prostate cancer patients. For pCT generation from MR images, a commercial solution for creating bulk-assigned pCTs, called MR for Attenuation Correction (MRCAT), was employed. The assigned pseudo-Hounsfield Unit (HU) values were adapted to yield an increased agreement to the reference CT in terms of proton range. Internal air cavities were copied from the CT to minimise inter-scan differences. CT- and MRCAT-based dose calculations for opposing beam IMPT plans were compared by gamma analysis and evaluation of clinically relevant target and organ at risk dose volume histogram (DVH) parameters. The proton range in beam’s eye view (BEV) was compared using single field uniform dose (SFUD) plans. On average, a (2%, 2 mm) gamma pass rate of 98.4% was obtained using a 10% dose threshold after adaptation of the pseudo-HU values. Mean differences between CT- and MRCAT-based dose in the DVH parameters were below 1 Gy (radiotherapy, is feasible following adaptation of the assigned pseudo-HU values.

Crystal Structure of an L-Carnitine Complex with Pyrogallol[4]arene

International Nuclear Information System (INIS)

Fujisawa, I; Takeuchi, D; Kitamura, Y; Okamoto, R; Aoki, K

2012-01-01

L-Carnitine is essential for the transport of long-chain fatty acids from cytosol into mitochondria for generating metabolic energy. The survey of crystal structures of carnitine-containing proteins in the Protein Data Bank reveals that carnitine can take several conformations with the quarternary trimethylammonium terminal being always bound to aromatic residues through cation-π interactions in acyltransferases or carnitine-binding proteins. In order to demonstrate the importance of cation-π interaction as a carnitine recognition mechanism in the artificial receptor-ligand system that mimics the carnitine-binding sites, we have determined the crystal structure of a complex formed between L-carnitine and pyrogallol[4]arene (pyrogallol cyclic tetramer: PCT) as a carnitine receptor, 2PCT·2(L-carnitine)·4EtOH. There form two crystallographically independent monomeric [PCT·L-carnitine] substructures, which further form an obliquely arranged capsule-like dimeric [PCT·L-carnitine] 2 structure through a pair of O-H (PCT)···O (L-carnitine) hydrogen bonds. This is the first report of PCT complex with chiral molecules. In each of the two monomeric [PCT·L-carnitine] substructures, the L-carnitine molecule takes the elongated form with an intramolecular hydrogen bond between the hydroxyl group and the carboxylate oxygen, and the cationic trimethylammonium moiety is incorporated into the cavity of the bowl-shaped PCT molecule through cation-π interactions. These features are similar to those at the D-carnitine-binding site in the crystal structure of the glycine betaine/carnitine/choline-binding protein complex.

Mussel byssus-inspired engineering of synergistic nanointerfacial interactions as sacrificial bonds into carbon nanotube-reinforced soy protein/nanofibrillated cellulose nanocomposites: Versatile mechanical enhancement

Science.gov (United States)

Wang, Zhong; Zhao, Shujun; Kang, Haijiao; Zhang, Wei; Zhang, Shifeng; Li, Jianzhang

2018-03-01

Achieving flexible and stretchable biobased nanocomposites combining high strength and toughness is still a very challenging endeavor. Herein, we described a novel and versatile biomimetic design for tough and high-performance TEMPO-oxidized nanofibrillated cellulose (TONFC)/soy protein isolate (SPI) nanocomposites, which are triggered by catechol-mimetic carbon nanotubes (PCT) and iron ions (Fe(III)) to yield a strong yet sacrificial metal-ligand motifs into a chemically cross-linked architecture network. Taking advantage of self-polymerization of catechol-inspired natural tannic acid, PCT nanohybrid was prepared through adhering reactive poly-(tannic acid) (PTA) layer onto surfaces of carbon nanotubes via a simple dip-coating process. The high-functionality PCT induced the formation of the metal-ligand bonds through the ionic coordinates between the catechol groups in PCT and -COOH groups of TONFC skeleton with Fe(III) mediation that mimicked mussel byssus. Upon stretching, this tailored TONFC-Fe(III)-catechol coordination bonds served as sacrificial bonds that preferentially detach prior to the covalent network, which gave rise to efficient energy dissipation that the nanocomposites integrity was survived. As a result of these kind of synergistic interfacial interactions (sacrificial and covalent bonding), the optimal nanocomposite films processed high tensile strength (ca. 11.5 MPa), large elongation (ca. 79.3%), remarkable toughness (ca. 6.9 MJ m-3), and favorable water resistance as well as electrical conductivity. The proposed bioinspired strategy for designing plant protein-based materials enables control over their mechanical performance through the synergistic engineering of sacrificial bonds into the composite interface.

Efficient Separation and Extraction of Vanadium and Chromium in High Chromium Vanadium Slag by Selective Two-Stage Roasting-Leaching

Science.gov (United States)

Wen, Jing; Jiang, Tao; Xu, Yingzhe; Liu, Jiayi; Xue, Xiangxin

2018-04-01

Vanadium and chromium are important rare metals, leading to a focus on high chromium vanadium slag (HCVS) as a potential raw material to extract vanadium and chromium in China. In this work, a novel method based on selective two-stage roasting-leaching was proposed to separate and extract vanadium and chromium efficiently in HCVS. XRD, FT-IR, and SEM were utilized to analyze the phase evolutions and microstructure during the whole process. Calcification roasting, which can calcify vanadium selectively using thermodynamics, was carried out in the first roasting stage to transfer vanadium into acid-soluble vanadate and leave chromium in the leaching residue as (Fe0.6Cr0.4)2O3 after H2SO4 leaching. When HCVS and CaO were mixed in the molar ratio CaO/V2O3 (n(CaO)/n(V2O3)) of 0.5 to 1.25, around 90 pct vanadium and less than 1 pct chromium were extracted in the first leaching liquid, thus achieving the separation of vanadium and chromium. In the second roasting stage, sodium salt, which combines with chromium easily, was added to the first leaching residue to extract chromium and 95.16 pct chromium was extracted under the optimal conditions. The total vanadium and chromium leaching rates were above 95 pct, achieving the efficient separation and extraction of vanadium and chromium. The established method provides a new technique to separate vanadium and chromium during roasting rather than in the liquid form, which is useful for the comprehensive application of HCVS.

Efficient Separation and Extraction of Vanadium and Chromium in High Chromium Vanadium Slag by Selective Two-Stage Roasting-Leaching

Science.gov (United States)

Wen, Jing; Jiang, Tao; Xu, Yingzhe; Liu, Jiayi; Xue, Xiangxin

2018-06-01

Vanadium and chromium are important rare metals, leading to a focus on high chromium vanadium slag (HCVS) as a potential raw material to extract vanadium and chromium in China. In this work, a novel method based on selective two-stage roasting-leaching was proposed to separate and extract vanadium and chromium efficiently in HCVS. XRD, FT-IR, and SEM were utilized to analyze the phase evolutions and microstructure during the whole process. Calcification roasting, which can calcify vanadium selectively using thermodynamics, was carried out in the first roasting stage to transfer vanadium into acid-soluble vanadate and leave chromium in the leaching residue as (Fe0.6Cr0.4)2O3 after H2SO4 leaching. When HCVS and CaO were mixed in the molar ratio CaO/V2O3 (n(CaO)/n(V2O3)) of 0.5 to 1.25, around 90 pct vanadium and less than 1 pct chromium were extracted in the first leaching liquid, thus achieving the separation of vanadium and chromium. In the second roasting stage, sodium salt, which combines with chromium easily, was added to the first leaching residue to extract chromium and 95.16 pct chromium was extracted under the optimal conditions. The total vanadium and chromium leaching rates were above 95 pct, achieving the efficient separation and extraction of vanadium and chromium. The established method provides a new technique to separate vanadium and chromium during roasting rather than in the liquid form, which is useful for the comprehensive application of HCVS.

Post-Operative Infection Is an Independent Risk Factor for Worse Long-Term Survival after Colorectal Cancer Surgery.

Science.gov (United States)

Kerin Povšič, Milena; Ihan, Alojz; Beovič, Bojana

2016-12-01

Colorectal cancer surgery is associated with a high incidence of post-operative infections, the outcome of which may be improved if diagnosed and treated early enough. We compared white blood cell (WBC) count, C-reactive protein (CRP), and procalcitonin (PCT) as predictors of post-operative infections and analyzed their impact on long-term survival. This retrospective study included 186 patients undergoing colorectal surgery. Post-operative values of WBC, CRP, and PCT were analyzed by the receiver operating characteristic (ROC) analysis. We followed infections 30 d after the surgery. A five-year survival was analyzed by Kaplan-Meier method and prognostic factors by Cox regression model. Fifty-five patients (29.5%) developed post-operative infection, the most frequent of which was surgical site infection (SSI). C-reactive protein on post-operative day three and PCT on post-operative day two demonstrated the highest diagnostic accuracy for infection (area under the curve [AUC] 0.739 and 0.735). C-reactive protein on post-operative day three was an independent predictor of infection. Five-year survival was higher in the non-infected group (70.8%), compared with the infected group (52.1%). The worst survival (40.9%) was identified in patients with organ/space SSI. Post-operative infection and tumor stage III-IV were independent predictors of a worse five-year survival. C-reactive protein on post-operative day three and PCT on post-operative day two may be early predictors of infection after colorectal cancer surgery. Post-operative infections in particular organ/space SSI have a negative impact on long-term survival.

Cerebral perfusion computerized tomography: influence of reference vessels, regions of interest and interobserver variability

International Nuclear Information System (INIS)

Soustiel, Jean F.; Mor, Nadav; Zaaroor, Menashe; Goldsher, Dorith

2006-01-01

There are still no standardized guidelines for perfusion computerized tomography (PCT) analysis. A total of 61 PCT studies were analyzed using either the anterior cerebral artery (ACA) or the middle cerebral artery (MCA) as the arterial reference, and the superior sagittal sinus (SSS) or the vein of Galen (VG) as the venous reference. The sizes of regions of interest (ROI) were investigated comparing PCT results obtained using a hemispheric ROI combined with vascular pixel elimination with those obtained using five smaller ROIs located over the cortex and basal ganglia. In addition, interobserver variations were explored using a standardized protocol. MCA-based measurements of cerebral blood flow (CBF) and blood volume (CBV) were in accordance with those obtained with the ACA except in 16 patients with ischemic stroke, in whom CBF was overestimated by the ipsilateral MCA. Venous maximal intensity was significantly lower with the VG when compared with the SSS, resulting in overestimation of CBF and CBV. However, in 13.3% of patients the VG ROI yielded higher maximal intensities than the SSS ROI. There was no difference in PCT results between hemispheric ROI and averaged separate ROI when vascular pixel elimination was used. Finally, interobserver variations were as high as 11% for CBF and 12% for CBV. The present results suggest that pathological rather than anatomical considerations should dictate the choice of the arterial ROI. For venous ROI, although SSS seems to be adequate in most instances, deep cerebral veins may occasionally generate higher maximal intensities and should therefore be selected. Importantly, significant user-dependency should be taken into account. (orig.)

Copeptin, procalcitonin and routine inflammatory markers-predictors of infection after stroke.

Directory of Open Access Journals (Sweden)

Felix Fluri

Full Text Available Early predictors for the development of stroke-associated infection may identify patients at high risk and reduce post-stroke infection and mortality.In 383 prospectively enrolled acute stroke patients we assessed time point and type of post-stroke infections (i.e. pneumonia, urinary tract infection (UTI other infection (OI. Blood samples were collected on admission, and days 1, and 3 to assess white blood cells (WBC, monocytes, C-reactive protein (CRP, procalcitonin (PCT, and copeptin. To determine the magnitude of association with the development of infections, odds ratios (OR were calculated for each prognostic blood marker. The discriminatory ability of different predictors was assessed, by calculating area under the receiver operating characteristic curves (AUC. Prognostic models including the three parameters with the best performance were identified.Of 383 patients, 66 (17.2% developed an infection after onset of stroke. WBC, CRP, copeptin and PCT were all independent predictors of any infection, pneumonia and UTI developed at least 24 hours after measurements. The combination of the biomarkers WBC, CRP and copeptin (AUC: 0.92 and WBC, CRP and PCT (AUC: 0.90 showed a better predictive accuracy concerning the development of pneumonia during hospitalization compared to each marker by itself (p-Wald <0.0001.Among ischemic stroke patients, copeptin, PCT, WBC and CRP measured on admission were predictors of infection in general, and specifically for pneumonia and UTI within 5 days after stroke. The combination of these biomarkers improved the prediction of patients who developed an infection.

Preliminary 2D design study for A ampersand PCT

International Nuclear Information System (INIS)

Keto, E.; Azevedo, S.; Roberson, P.

1995-03-01

Lawrence Livermore National Laboratory is currently designing and constructing a tomographic scanner to obtain the most accurate possible assays of radioactivity in barrels of nuclear waste in a limited amount of time. This study demonstrates a method to explore different designs using laboratory experiments and numerical simulations. In particular, we examine the trade-off between spatial resolution and signal-to-noise. The simulations are conducted in two dimensions as a preliminary study for three dimensional imaging. We find that the optimal design is entirely dependent on the expected source sizes and activities. For nuclear waste barrels, preliminary results indicate that collimators with widths of 1 to 3 inch and aspect ratios of 5:1 to 10:1 should perform well. This type of study will be repeated in 3D in more detail to optimize the final design

Dissolution rates of DWPF glasses from long-term PCT

International Nuclear Information System (INIS)

Ebert, W.L.; Tam, S.W.

1996-01-01

We have characterized the corrosion behavior of several Defense Waste Processing Facility (DWPF) reference waste glasses by conducting static dissolution tests with crushed glasses. Glass dissolution rates were calculated from measured B concentrations in tests conducted for up to five years. The dissolution rates of all glasses increased significantly after certain alteration phases precipitated. Calculation of the dissolution rates was complicated by the decrease in the available surface area as the glass dissolves. We took the loss of surface area into account by modeling the particles to be spheres, then extracting from the short-term test results the dissolution rate corresponding to a linear decrease in the radius of spherical particles. The measured extent of dissolution in tests conducted for longer times was less than predicted with this linear dissolution model. This indicates that advanced stages of corrosion are affected by another process besides dissolution, which we believe to be associated with a decrease in the precipitation rate of the alteration phases. These results show that the dissolution rate measured soon after the formation of certain alteration phases provides an upper limit for the long-term dissolution rate, and can be used to determine a bounding value for the source term for radionuclide release from waste glasses. The long-term dissolution rates measured in tests at 20,000 per m at 90 degrees C in tuff groundwater at pH values near 12 for the Environmental Assessment glass and glasses made with SRL 131 and SRL 202 frits, respectively

Resting functional imaging tools (MRS, SPECT, PET and PCT)

NARCIS (Netherlands)

van der Naalt, Joukje; Grafman, Jordan; Salazar, Andres M

2015-01-01

Functional imaging includes imaging techniques that provide information about the metabolic and hemodynamic status of the brain. Most commonly applied functional imaging techniques in patients with traumatic brain injury (TBI) include magnetic resonance spectroscopy (MRS), single photon emission

Viscosity of Heterogeneous Silicate Melts: A Non-Newtonian Model

Science.gov (United States)

Liu, Zhuangzhuang; Blanpain, Bart; Guo, Muxing

2017-12-01

The recently published viscosity data of heterogeneous silicate melts with well-documented structure and experimental conditions are critically re-analyzed and tabulated. By using these data, a non-Newtonian viscosity model incorporating solid fraction, solid shape, and shear rate is proposed on the basis of the power-law equation. This model allows calculating the viscosity of the heterogeneous silicate melts with solid fraction up to 34 vol pct. The error between the calculated and measured data is evaluated to be 32 pct, which is acceptable considering the large error in viscosity measurement of the completely liquid silicate melt.

Computed tomography synthesis from magnetic resonance images in the pelvis using multiple random forests and auto-context features

DEFF Research Database (Denmark)

Andreasen, Daniel; Morgenthaler Edmund, Jens; Zografos, Vasileios

2016-01-01

In radiotherapy treatment planning that is only based on magnetic resonance imaging (MRI), the electron density information usually obtained from computed tomography (CT) must be derived from the MRI by synthesizing a so-called pseudo CT (pCT). This is a non-trivial task since MRI intensities...... as measured by water-equivalent path lengths. We compare the performance of our method against two baseline pCT strategies, which either set all MRI voxels in the subject equal to the CT value of water, or in addition transfer the bone volume from the real CT. We show an improved performance compared to both...

Investigation on effect of iron and corundum content on corrosion resistance of the NiFe-Al2O3 coatings

International Nuclear Information System (INIS)

Starosta, R.; Zielinski, A.

1999-01-01

The alloy NiFe and composite NiFe-Al 2 O 3 coatings, obtained by electrodeposition on the base of cast iron, were investigated. The iron content in alloy coatings was dependent on iron content in galvanic bath, and was estimated by means of X-ray microanalysis at 18.5 wt. pct. and 41.2 wt. pct. No existence of ordered Ni 3 Fe phase was found by diffraction technique. Both potentiodynamic and impedance measurements disclosed that a presence of Al 2 O 3 or increasing iron content in the layer caused the decrease in corrosion resistance. (author)

Investigation of Sludge Batch 3 (Macrobatch 4) Glass Sample Anomalous Behavior

International Nuclear Information System (INIS)

Bannochie, C. J.; Bibler, N. E.; Peeler, D. K.

2005-01-01

Two Defense Waste Processing Facility (DWPF) glass samples from Sludge Batch 3 (SB3) (Macrobatch 4) were received by the Savannah River National Laboratory (SRNL) on February 23, 2005. One sample, S02244, was designated for the Product Consistency Test (PCT) and elemental and radionuclide analyses. The second sample, S02247, was designated for archival storage. The samples were pulled from the melter pour stream during the feeding of Melter Feed Tank (MFT) Batch 308 and therefore roughly correspond to feed from Slurry Mix Evaporator (SME) Batches 306-308. During the course of preparing sample S02244 for PCT and other analyses two observations were made which were characterized as ''unusual'' or anomalous behavior relative to historical observations of glasses prepared for the PCT. These observations ultimately led to a series of scoping tests in order to determine more about the nature of the behavior and possible mechanisms. The first observation was the behavior of the ground glass fraction (-100 +200 mesh) for PCT analysis when contacted with deionized water during the washing phase of the PCT procedure. The behavior was analogous to that of an organic compound in the presence of water: clumping, floating on the water surface, and crawling up the beaker walls. In other words, the glass sample did not ''wet'' normally, displaying a hydrophobic behavior in water. This had never been seen before in 18 years SRNL PCT tests on either radioactive or non-radioactive glasses. Typical glass behavior is largely to settle to the bottom of the water filled beaker, though there may be suspended fines which result in some cloudiness to the wash water. The typical appearance is analogous to wetting sand. The second observation was the presence of faint black rings at the initial and final solution levels in the Teflon vessels used for the mixed acid digestion of S02244 glass conducted for compositional analysis. The digestion is composed of two stages, and at both the

Correlação entre o índice de massa corporal e a prega cutânea tricipital em crianças da cidade de Paulínia, São Paulo, SP Body mass index and triceps skinfold correlation in children from Paulínia city, São Paulo, SP

Directory of Open Access Journals (Sweden)

Mariana Porto Zambon

2003-06-01

Full Text Available O índice de massa corporal (IMC tem sido indicado como método de escolha para o diagnóstico da obesidade em adultos e crianças. OBJETIVO: Estudar a correlação existente entre o IMC e a prega cutânea tricipital (PCT. MÉTODOS: Foram avaliadas 4.236 crianças de 3,1 a 10,9 anos, 48,3% do sexo masculino e 51,6% feminino, de quatro estudos realizados em Paulínia, SP, Brasil. Mediu-se o peso e a estatura, com os quais calculou-se o IMC. A PCT foi medida com paquímetro Holtain. Os dados foram transformados em escores Z e comparados à curva norte-americana (Frisancho, 1993. A população foi dividida em grupos de acordo com os escores Z do IMC: grupo A escore Z 1. Realizou-se uma análise de regressão linear múltipla (método stepwise. Os dados foram processados no SPSS. RESULTADOS: O grupo A apresentou menor variabilidade na PCT (média 7,8; DP = 2,3 quando comparado aos demais (B: média 10,1; DP=4 e C: média 17,8; DP=4,4. Na análise da regressão linear, considerando todos os casos, a PCT apresentou R²=0,478. Nos grupos B e C a PCT teve R²=0,364 e 0,368, respectivamente enquanto no grupo A foi apenas 0,032. CONCLUSÃO: A correlação entre o IMC e a PCT é elevada no grupo de crianças com risco de obesidade (grupo C, o que justifica a substituição do uso da PCT pelo IMC em estudos populacionais de obesidade em escolares brasileiros.Body mass index (BMI has been considered a criterion to define and analyse obesity in adults and children. BACKGROUND: the purpose of this study was to evaluate the correlation between BMI and triceps skinfold (TSF. METHODS: there were studied 4,236 children (3.1-10.9y; 48.3%M:51.6%F, from four studies made in Paulínia, SP-Brazil. Height, weight and TSF (Holtain caliper were measured. For each children BMI was calculated and transformed in SDS, according to North American data (Frisancho, 1993. Multiple linear regression analysis (stepwise was used for the whole population and in three groups according

Method for screening prevention and control measures and technologies based on groundwater pollution intensity assessment

Energy Technology Data Exchange (ETDEWEB)

Li, Juan, E-mail: lijuan@craes.org.cn [College of Water Sciences, Beijing Normal University, Beijing 100875 (China); Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012 (China); Yang, Yang [College of Environment, Beijing Normal University, Beijing 100875 (China); Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012 (China); Huan, Huan; Li, Mingxiao [Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012 (China); Xi, Beidou, E-mail: xibd413@yeah.net [Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012 (China); Lanzhou Jiaotong University, Lanzhou 730070 (China); Lv, Ningqing [Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012 (China); Wu, Yi [Guizhou Academy of Environmental Science and Designing, Guizhou 550000 (China); Xie, Yiwen, E-mail: qin3201@126.com [School of Chemical and Environmental Engineering, Dongguan University of Technology, Dongguan, 523808 (China); Li, Xiang; Yang, Jinjin [Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012 (China)

2016-05-01

This paper presents a system for determining the evaluation and gradation indices of groundwater pollution intensity (GPI). Considering the characteristics of the vadose zone and pollution sources, the system decides which anti-seepage measures should be implemented at the contaminated site. The pollution sources hazards (PSH) and groundwater intrinsic vulnerability (GIV) are graded by the revised Nemerow Pollution Index and an improved DRTAS model, respectively. GPI is evaluated and graded by a double-sided multi-factor coupling model, which is constructed by the matrix method. The contaminated sites are categorized as prior, ordinary, or common sites. From the GPI results, we develop guiding principles for preventing and removing pollution sources, procedural interruption and remediation, and end treatment and monitoring. Thus, we can select appropriate prevention and control technologies (PCT). To screen the technological schemes and optimize the traditional analytical hierarchy process (AHP), we adopt the technique for order preference by the similarity to ideal solution (TOPSIS) method. Our GPI approach and PCT screening are applied to three types of pollution sites: the refuse dump of a rare earth mine development project (a potential pollution source), a chromium slag dump, and a landfill (existing pollution sources). These three sites are identified as ordinary, prior, and ordinary sites, respectively. The anti-seepage materials at the refuse dump should perform as effectively as a 1.5-m-thick clay bed. The chromium slag dump should be preferentially treated by soil flushing and in situ chemical remediation. The landfill should be treated by natural attenuation technology. The proposed PCT screening approach was compared with conventional screening methods results at the three sites and proved feasible and effective. The proposed method can provide technical support for the monitoring and management of groundwater pollution in China. - Highlights: • An

The effect of sheet processing on the microstructure, tensile, and creep behavior of INCONEL alloy 718

Science.gov (United States)

Boehlert, C. J.; Dickmann, D. S.; Eisinger, Ny. N. C.

2006-01-01

The grain size, grain boundary character distribution (GBCD), creep, and tensile behavior of INCONEL alloy 718 (IN 718) were characterized to identify processing-microstructure-property relationships. The alloy was sequentially cold rolled (CR) to 0, 10, 20, 30, 40, 60, and 80 pct followed by annealing at temperatures between 954 °C and 1050 °C and the traditional aging schedule used for this alloy. In addition, this alloy can be superplastically formed (IN 718SPF) to a significantly finer grain size and the corresponding microstructure and mechanical behavior were evaluated. The creep behavior was evaluated in the applied stress (σ a ) range of 300 to 758 MPa and the temperature range of 638 °C to 670 °C. Constant-load tensile creep experiments were used to measure the values of the steady-state creep rate and the consecutive load reduction method was used to determine the values of backstress (σ0). The values for the effective stress exponent and activation energy suggested that the transition between the rate-controlling creep mechanisms was dependent on effective stresses (σ e =σ a σ0) and the transition occurred at σ e ≅ 135 MPa. The 10 to 40 pct CR samples exhibited the greatest 650 °C strength, while IN 718SPF exhibited the greatest room-temperature (RT) tensile strength (>1550 MPa) and ductility (ɛ f >16 pct). After the 954 °C annealing treatment, the 20 pct CR and 30 pct CR microstructures exhibited the most attractive combination of elevated-temperature tensile and creep strength, while the most severely cold-rolled materials exhibited the poorest elevated-temperature properties. After the 1050 °C annealing treatment, the IN 718SPF material exhibited the greatest backstress and best creep resistance. Electron backscattered diffraction was performed to identify the GBCD as a function of CR and annealing. The data indicated that annealing above 1010 °C increased the grain size and resulted in a greater fraction of twin boundaries, which in

Method for screening prevention and control measures and technologies based on groundwater pollution intensity assessment

International Nuclear Information System (INIS)

Li, Juan; Yang, Yang; Huan, Huan; Li, Mingxiao; Xi, Beidou; Lv, Ningqing; Wu, Yi; Xie, Yiwen; Li, Xiang; Yang, Jinjin

2016-01-01

This paper presents a system for determining the evaluation and gradation indices of groundwater pollution intensity (GPI). Considering the characteristics of the vadose zone and pollution sources, the system decides which anti-seepage measures should be implemented at the contaminated site. The pollution sources hazards (PSH) and groundwater intrinsic vulnerability (GIV) are graded by the revised Nemerow Pollution Index and an improved DRTAS model, respectively. GPI is evaluated and graded by a double-sided multi-factor coupling model, which is constructed by the matrix method. The contaminated sites are categorized as prior, ordinary, or common sites. From the GPI results, we develop guiding principles for preventing and removing pollution sources, procedural interruption and remediation, and end treatment and monitoring. Thus, we can select appropriate prevention and control technologies (PCT). To screen the technological schemes and optimize the traditional analytical hierarchy process (AHP), we adopt the technique for order preference by the similarity to ideal solution (TOPSIS) method. Our GPI approach and PCT screening are applied to three types of pollution sites: the refuse dump of a rare earth mine development project (a potential pollution source), a chromium slag dump, and a landfill (existing pollution sources). These three sites are identified as ordinary, prior, and ordinary sites, respectively. The anti-seepage materials at the refuse dump should perform as effectively as a 1.5-m-thick clay bed. The chromium slag dump should be preferentially treated by soil flushing and in situ chemical remediation. The landfill should be treated by natural attenuation technology. The proposed PCT screening approach was compared with conventional screening methods results at the three sites and proved feasible and effective. The proposed method can provide technical support for the monitoring and management of groundwater pollution in China. - Highlights: • An

Correlation of iodine uptake and perfusion parameters between dual-energy CT imaging and first-pass dual-input perfusion CT in lung cancer.

Science.gov (United States)

Chen, Xiaoliang; Xu, Yanyan; Duan, Jianghui; Li, Chuandong; Sun, Hongliang; Wang, Wu

2017-07-01

To investigate the potential relationship between perfusion parameters from first-pass dual-input perfusion computed tomography (DI-PCT) and iodine uptake levels estimated from dual-energy CT (DE-CT).The pre-experimental part of this study included a dynamic DE-CT protocol in 15 patients to evaluate peak arterial enhancement of lung cancer based on time-attenuation curves, and the scan time of DE-CT was determined. In the prospective part of the study, 28 lung cancer patients underwent whole-volume perfusion CT and single-source DE-CT using 320-row CT. Pulmonary flow (PF, mL/min/100 mL), aortic flow (AF, mL/min/100 mL), and a perfusion index (PI = PF/[PF + AF]) were automatically generated by in-house commercial software using the dual-input maximum slope method for DI-PCT. For the dual-energy CT data, iodine uptake was estimated by the difference (λ) and the slope (λHU). λ was defined as the difference of CT values between 40 and 70 KeV monochromatic images in lung lesions. λHU was calculated by the following equation: λHU = |λ/(70 - 40)|. The DI-PCT and DE-CT parameters were analyzed by Pearson/Spearman correlation analysis, respectively.All subjects were pathologically proved as lung cancer patients (including 16 squamous cell carcinoma, 8 adenocarcinoma, and 4 small cell lung cancer) by surgery or CT-guided biopsy. Interobserver reproducibility in DI-PCT (PF, AF, PI) and DE-CT (λ, λHU) were relatively good to excellent (intraclass correlation coefficient [ICC]Inter = 0.8726-0.9255, ICCInter = 0.8179-0.8842; ICCInter = 0.8881-0.9177, ICCInter = 0.9820-0.9970, ICCInter = 0.9780-0.9971, respectively). Correlation coefficient between λ and AF, and PF were as follows: 0.589 (P input CT perfusion analysis method can be applied to assess blood supply of lung cancer patients. Preliminary results demonstrated that the iodine uptake relevant parameters derived from DE-CT significantly correlated with perfusion

[Personalized cell therapy for early postoperative bullous keratopathy (experimental proof and clinical results)].

Science.gov (United States)

Kasparov, A A; Kasparova, Evg A; Fadeeva, L L; Subbot, A M; Borodina, N V; Kasparova, E A; Kobzova, M V; Musaeva, G M; Pavliuk, A S

2013-01-01

The article presents the results of a long-term research on development and clinical application of personalized cell therapy (PCT) for treatment of early postoperative (manifesting within the first 3 months after surgery) bullous keratopathy (BK). The method of intracameral PCT implies in vitro incubation of the patient's blood sample with poly(A:U) stimulator, separation of the serum with activated leukocytes, and injection of the final cell preparation into the anterior chamber. The fundamental part of the research was aimed at a detailed description of the cell preparation and investigation of its possible mechanisms of action. Cytokine and growth factor level in the cell preparation suggested that its high clinical efficacy might be due to its ability to improve regeneration of damaged corneal endothelium. The clinical study was conducted on a group of 52 patients with early BK. A significant effect (smoothing of the Descement's membrane folds, complete resorption of corneal edema, improvement of corneal transparency, reduction of corneal thickness and increase of visual acuity by 0.49 +/- 0.27) was achieved in 44.2% of patients, while partial effect was seen in 21.1% of patients. There was no clinical effect in 34.6% of patients. In those patients who developed significant or partial clinical effect after the PCT, many endotheliocytes appeared to have multiple nuclei (2 and more). In some patients polyploid nuclei persisted for 3-5 years after the treatment. Polyploidy results from incomplete mitosis which might be due to regenerative processes in the endothelium stimulated by the PCT. Obviously, high efficacy and relative simplicity of the method should promote its further clinical introduction.

Alumina-Forming Austenitic Stainless Steels Strengthened by Laves Phase and MC Carbide Precipitates

Science.gov (United States)

Yamamoto, Y.; Brady, M. P.; Lu, Z. P.; Liu, C. T.; Takeyama, M.; Maziasz, P. J.; Pint, B. A.

2007-11-01

Creep strengthening of Al-modified austenitic stainless steels by MC carbides or Fe2Nb Laves phase was explored. Fe-20Cr-15Ni-(0-8)Al and Fe-15Cr-20Ni-5Al base alloys (at. pct) with small additions of Nb, Mo, W, Ti, V, C, and B were cast, thermally-processed, and aged. On exposure from 650 °C to 800 °C in air and in air with 10 pct water vapor, the alloys exhibited continuous protective Al2O3 scale formation at an Al level of only 5 at. pct (2.4 wt pct). Matrices of the Fe-20Cr-15Ni-5Al base alloys consisted of γ (fcc) + α (bcc) dual phase due to the strong α-Fe stabilizing effect of the Al addition and exhibited poor creep resistance. However, adjustment of composition to the Fe-15Cr-20Ni-5Al base resulted in alloys that were single-phase γ-Fe and still capable of alumina scale formation. Alloys that relied solely on Fe2Nb Laves phase precipitates for strengthening exhibited relatively low creep resistance, while alloys that also contained MC carbide precipitates exhibited creep resistance comparable to that of commercially available heat-resistant austenitic stainless steels. Phase equilibria studies indicated that NbC precipitates in combination with Fe2Nb were of limited benefit to creep resistance due to the solution limit of NbC within the γ-Fe matrix of the alloys studied. However, when combined with other MC-type strengtheners, such as V4C3 or TiC, higher levels of creep resistance were obtained.

Effect of Cold Deformation and Annealing on the Microstructure and Tensile Properties of a HfNbTaTiZr Refractory High Entropy Alloy

Science.gov (United States)

Senkov, O. N.; Pilchak, A. L.; Semiatin, S. L.

2018-05-01

The microstructure and tensile properties of HfNbTaTiZr after cold working and annealing were investigated. Cold work was introduced by axial compression followed by rolling resulting in a total thickness reduction of 89 pct without any evidence of cracking. The cold-worked material retained a single-phase microstructure and had a room temperature tensile yield stress σ 0.2 = 1438 MPa, peak true stress σ p = 1495 MPa, and true fracture strain ɛ f = 5 pct. Annealing at 800 °C for up to 256 hours resulted in the precipitation of Nb and Ta rich particles with a BCC crystal structure inside a Hf-and-Zr-enriched BCC matrix. The second phase particles nucleated heterogeneously inside deformation bands and slip lines and coarsened during annealing. Analysis of the coarsening behavior suggested that kinetics were controlled by the diffusion of Nb and Ta. In the two-phase material, σ 0.2 and σ p decreased from 1159 to 1071 MPa and from 1174 to 1074 MPa, respectively, with an increase in particle diameter from 0.18 to 0.72 μm, while ɛ f remained between 5 and 8 pct. Full recrystallization and normal grain growth, with the activation energy of 238 kJ/mol and activation volume of 5.3 to 9.6 m3/mol, occurred during annealing above 1000 °C. After heat treatment at this temperature, the alloy was characterized by a single-phase BCC structure with σ 0.2 = 1110 to 1115 MPa, σ p = 1160 to 1195 MPa, and ɛ f = 12 to 19 pct with the maximum values attained after annealing for 1 hour.

Diagnostic value of serum procalcitonin levels in children with meningitis: a comparison with blood leukocyte count and C-reactive protein

International Nuclear Information System (INIS)

Ibrahim, K.A.; Wahab, A.A.A.; Ibrahim, A.S.

2011-01-01

Objectives: To determine the level of serum procalcitonin, blood leukocyte count (TLC) and C-reactive protein (CRP) in children with bacterial and non bacterial meningitis and document their efficacy in differential diagnosis. Also described are procalcitonin levels variation during treatment. Methods: From March 2005 to February 2008, we evaluated 38 clinically suspected meningitis patients in the paediatric departments, Al-Jedaany Hospital, Jeddah, KSA, for Serum procalcitonin, CRP, TLC and Lumbar punctures and CSF analysis. Patients were classified into bacterial meningitis group I (18) and non bacterial meningitis group II (20). Results: Serum PCT levels were significantly higher in bacterial meningitis (BM) 9 mean 4.8 +- 3.85 ng/ml (2.9-11.6)) compared with non bacterial meningitis (NBM) (mean 0.38 +- 0.25 ng/ml(0.31-0.61)) P< 0.001). Mean of all CSF parameters, TLC (15,000 +- 2,900 cell/ml(BM) and 9,500 +-1,105 cell/ml(NBM))and CRP (20 +- 6.8 mg/l (BM) and 12.5 +-12.0 mg/l(NBM))showed a zone of overlapping between the two groups. There is a positive correlation between serum PCT, TLC and CRP in bacterial and non bacterial meningitis cases but this relation becomes highly significant with bacterial meningitis positive group. Day 3 and day 6 treatment serum PCT was less than on admission levels (P<0.001). Conclusion: PCT can be used in the early diagnosis of bacterial meningitis and may be a useful adjunct in differentiating bacterial and non bacterial meningitis than CRP or TLC and diminishing the value of lumbar puncture performed 48-72 hours after admission to assess treatment efficacy. (author)

An Adaptive Off-Line Procedure for Radiotherapy of Prostate Cancer

International Nuclear Information System (INIS)

Nuver, Tonnis T.; Hoogeman, Mischa S.; Remeijer, Peter; Herk, Marcel van; Lebesque, Joos V.

2007-01-01

Purpose: To determine the planning target volume (PTV) margin for an adaptive radiotherapy procedure that uses five computed tomography (CT) scans to calculate an average prostate position and rectum shape. To evaluate alternative methods to determine an average rectum based on a single delineation. Methods and Materials: Repeat CT scans (8-13) of 19 patients were used. The contoured prostates of the first four scans were matched on the planning CT (pCT) prostate contours. With the resulting translations and rotations the average prostate position was determined. An average rectum was obtained by either averaging the coordinates of corresponding points on the rectal walls or by selecting the 'best' rectum or transforming the pCT rectum. Dose distributions were calculated for various expanded average prostates. The remaining CT scans were used to determine the dose received by prostate and rectum during treatment. Results: For the prostate of the pCT scan and a 10-mm margin, all patients received more than 95% of the prescribed dose to 95% of the prostate. For the average prostate, a margin of 7 mm was needed to obtain a similar result (average PTV reduction 30%). The average rectum overestimated the mean dose to the rectum by 0.4 ± 1.6 Gy, which was better than the pCT rectum (2.1 ± 3.0 Gy) and the alternative average rectums (1.0 ± 2.6 Gy and 1.4 ± 3.2 Gy). Conclusions: Our adaptive procedure allows for reduction of the PTV margin to 7 mm without decreasing prostate coverage during treatment. For accurate estimation of the rectum dose, rectums need to be delineated and averaged over multiple scans

Laboratory testing of glasses for Lockheed Idaho Technology Company: Final report

International Nuclear Information System (INIS)

Ellison, A.J.G.; Buck, E.C.; Dietz, N.L.; Ebert, W.L.; Luo, J.S.; Wolf, S.F.; Bates, J.K.

1997-06-01

Tests have been conducted at Argonne National Laboratory (ANL) in support of the efforts of Lockheed Idaho Technology Company (LITCO) to vitrify high-level waste calcines. Tests were conducted with three classes of LITCO glass formulations: Formula 127 (fluorine-bearing), Formula 532 (fluorine-free), and 630 series (both single- and mixed-alkali) glasses. The test matrices included, as appropriate, the Product Consistency Test Method B (PCT-B), the Materials Characterization Center Test 1 (MCC-1), and the Argonne vapor hydration test (VHT). Test durations ranged from 7 to 183 d. In 7-d PCT-Bs, normalized mass losses of major glass-forming elements for the LITCO glasses are similar to, or lower than, normalized mass losses obtained for other domestic candidate waste glasses. Formula 532 glasses form zeolite alteration phases relatively early in their reaction with water. The formation of those phases increased the dissolution rate. In contrast, the Formula 127 glass is highly durable and forms alteration phases only after prolonged exposure to water in tests with very high surface area to volume ratios; these alteration phases have a relatively small effect on the rate of glass corrosion. No alteration phases formed within the maximum test duration of 183 d in PCT-Bs with the 630 series glasses. The corrosion behavior of the mixed-alkali 630 series glasses is similar to that of 630 series glasses containing sodium alone. In VHTs, both single- and mixed-alkali glasses form zeolite phases that increase the rate of glass reaction. The original 630 series glasses and those based on a revised surrogate calcine formulation react at the same rate in PCT-Bs and form the same major alteration phases in VHTs

GEANT4 simulations for Proton computed tomography applications

International Nuclear Information System (INIS)

Yevseyeva, Olga; Assis, Joaquim T. de; Evseev, Ivan; Schelin, Hugo R.; Shtejer Diaz, Katherin; Lopes, Ricardo T.

2011-01-01

Proton radiation therapy is a highly precise form of cancer treatment. In existing proton treatment centers, dose calculations are performed based on X-ray computed tomography (CT). Alternatively, one could image the tumor directly with proton CT (pCT). Proton beams in medical applications deal with relatively thick targets like the human head or trunk. Thus, the fidelity of proton computed tomography (pCT) simulations as a tool for proton therapy planning depends in the general case on the accuracy of results obtained for the proton interaction with thick absorbers. GEANT4 simulations of proton energy spectra after passing thick absorbers do not agree well with existing experimental data, as showed previously. The spectra simulated for the Bethe-Bloch domain showed an unexpected sensitivity to the choice of low-energy electromagnetic models during the code execution. These observations were done with the GEANT4 version 8.2 during our simulations for pCT. This work describes in more details the simulations of the proton passage through gold absorbers with varied thickness. The simulations were done by modifying only the geometry in the Hadron therapy Example, and for all available choices of the Electromagnetic Physics Models. As the most probable reasons for these effects is some specific feature in the code or some specific implicit parameters in the GEANT4 manual, we continued our study with version 9.2 of the code. Some improvements in comparison with our previous results were obtained. The simulations were performed considering further applications for pCT development. The authors want to thank CNPq, CAPES and 'Fundacao Araucaria' for financial support of this work. (Author)

Evaluation of central and peripheral corneal thicknesses in patients with rheumatoid arthritis

Directory of Open Access Journals (Sweden)

Alime Gunes

2015-08-01

Full Text Available ABSTRACTPurpose:To evaluate central corneal thickness (CCT and peripheral corneal thickness (PCT in patients with rheumatoid arthritis (RA and to assess the relationships among the corneal parameters, dry eye disease, and clinical variables of RA.Methods:A total of 58 RA patients and 58 control subjects participated in this study. A detailed ophthalmological examination was performed on each subject. Dry eye evaluation was performed using Schirmer’s test, tear break-up time (TBUT, corneal fluorescein staining, and Ocular Surface Disease Index (OSDI. Corneal thickness at the apex point, the center of the pupil, the thinnest point, and PCT (3 mm from the apex to the superior, inferior, nasal, and temporal locations were evaluated using Scheimpflug imaging (Pentacam®. Additionally, the relative peripheral index (RPI was calculated by dividing the PCT by the CCT. The disease severity and quality of life were evaluated with DAS28 and HAQ, respectively. The laboratory evaluation comprised ESR and CRP.Results:The mean corneal thicknesses at the apex point, the center of the pupil, the thinnest point, and the superior, inferior, nasal, and temporal points were significantly thinner in RA patients than controls. Schirmer’s test scores and TBUT were significantly lower, and corneal staining and OSDI scores were significantly higher in RA patients. There were no significant correlations between the corneal parameters and the clinical variables of RA or dry eye tests.Conclusion:The CCT and PCT were thinner in RA patients compared to those in control subjects. However, there were no significant correlations between the corneal parameters and the clinical variables of RA or dry eye tests.

Living with a carbon allowance: The experiences of Carbon Rationing Action Groups and implications for policy

International Nuclear Information System (INIS)

Howell, Rachel A.

2012-01-01

Carbon Rationing Action Groups (CRAGs) are grassroots voluntary groups of citizens concerned about climate change, who set themselves a carbon allowance each year and provide support to members seeking to reduce their direct carbon emissions from household energy use and personal transport. Some groups have a financial penalty for carbon emitted in excess of the ration, and systems whereby under-emitters are rewarded using the monies collected from over-emitters. CRAGs therefore operate the nearest scheme in existence to the proposed policy of Personal Carbon Trading (PCT). This paper reports the findings of a study of the opinions and experiences of individuals involved in CRAGs (‘CRAGgers’). In general, interviewees have made significant behavioural changes and emissions reductions, but many would be unwilling to sell spare carbon allowances within a national PCT system. The choices made by CRAGgers with respect to the design and operation of their ‘carbon accounting’, their experiences of reducing fossil fuel energy use, and their views on personal carbon trading at CRAG and national level are discussed. Some possible implications for PCT and other policies are considered, as well as the limitations of CRAGs in informing an understanding of the potential impacts and operation of PCT. - Highlights: ► Reports opinions and experiences of members of Carbon Rationing Action Groups (CRAGs). ► Many interviewees have made significant reductions to their carbon footprint. ► CRAGs offer insights into individuals' experiences of living with a carbon allowance. ► Most CRAGs involve highly motivated individuals and avoid trading. ► They nonetheless offer some insights into Personal Carbon Trading and other policies.

Hot Ductility Behavior of Boron Containing Microalloyed Steels with Varying Manganese Contents

Science.gov (United States)

Brune, Tobias; Senk, Dieter; Walpot, Raphael; Steenken, Bernhard

2015-02-01

The hot ductility is measured for six different steel grades with different microalloying elements and with varying manganese contents using the hot tensile test machine with melting/solidification unit at the Department of Ferrous Metallurgy RWTH Aachen University. To identify the influence of manganese on hot ductility, tests are performed with varying the manganese content from 0.7 to 18.2 wt pct, a high manganese steel. Additionally, the effect of different cooling and strain rates is analyzed by changing the particular rate for selected samples in the minima. To investigate and detect the cause of cracking during testing, the fracture surfaces in the ductility minima are considered with scanning electron microscope-energy dispersive X-ray spectroscopy. Thermodynamic modeling is conducted on basis of the commercial software ThermoCalc©. A sharp decrease of the hot ductility is recognizable at 1398 K (1125 °C), at only 0.7 wt pct manganese because of the low manganese to sulfur ratio. The grades with a Mn content up to 1.9 wt pct show a good ductility with minimal ductility loss. In comparison, the steel grade with 18.2 wt pct has a poor hot ductility. Because of the formation of complex precipitates, where several alloying elements are involved, the influence of boron on hot ductility is not fully clarified. By increasing the cooling rate, the reduction of area values are shifted to smaller values. For high test temperatures, these measured values are decreased for lower strain rates. Thereby, an early drop of the ductility is noticeable for the high temperatures around 1373 K (1100 °C).

[Results of thrombolyses procedures in acute ischemic cerebral stroke realized in Kraków 2004-2007--Grant Ministry of Science and Information].

Science.gov (United States)

Popiela, Tadeusz J; Urbanik, Andrzej; Słowik, Agnieszka

2010-01-01

To lower the number of complications of acute cerebral ischemic stroke and to reduce the time of rehabilitation in these patients it is necessary to induce treatment within the first 3 hours of the onset of the stroke. Early intervention however, is possible only in cases with the confirm localized ischemic focus visualized in one of the diagnostic imaging methods. The most widespread is CT, hovewer the first symptoms of ischemic stroke can be seen not beforel2 hours of the onset. The study evaluated the effectiveness of early diagnostics of ischemic stroke using perfusion CT (pCT) with subsequent intravenous or intra-arterial thrombolysis. The patients with ischemic stroke confirmed by pCT and qualified to thrombolysis in the first 3 hours of the onset of the stroke were randomly selected to intravenous or intra-arterial thrmobolysis. Those, who were 3 to 6 hours of the onset of the stroke were qualified to intra-arterial thrombolysis. A study group consisted of 377 patients hospitalized due to ischemic stroke. Of these pCT was performed in 76 cases, intravenous thrombolysis in 4 and intra-arterial thrombolysis in 2. Clinical condition substantially improved in 3 patients. Obtained results indicate the necessity to introduce pCT to the routine diagnostics of the acute ischemic stroke. A small number of patients eligible for thrombolysis does not allow to compare the effectiveness of intra-arterial and intravenous thrombolysis, however the project allowed to work out the efficient system of diagnostics and treatment of the acute ischemic stroke in the area of Krakow based on the standards used in the European countries.

Photothermal coherence tomography for 3-D visualization and structural non-destructive imaging of a wood inlay

Science.gov (United States)

Tavakolian, Pantea; Sfarra, Stefano; Gargiulo, Gianfranco; Sivagurunathan, Koneshwaran; Mandelis, Andreas

2018-06-01

The aim of this research is to investigate the suitability of truncated correlation photothermal coherence tomography (TC-PCT) for the non-destructive imaging of a replica of a real inlay to identify subsurface features that often are invisible areas of vulnerability and damage. Defects of inlays involve glue-rich areas, glue-starved areas, termite attack, insect damage, and laminar splitting. These defects have the potential to result in extensive damage to the art design layers of inlays. Therefore, there is a need for an imaging technique to visualize and determine the location of defects within the sample. The recently introduced TC-PCT modality proved capable of providing 3-D images of specimens with high axial resolution, deep subsurface depth profiling capability, and high signal-to-noise ratio (SNR). Therefore, in this study the authors used TC-PCT to image a fabricated inlay sample with various natural and artificial defects in the middle and top layers. The inlay in question reproduces to scale a piece of art preserved in the "Mirror room" of the Castle Laffitte in France. It was built by a professional restorer following the ancient procedure named element by element. Planar TC-PCT images of the inlay were stacked coherently to provide 3-D visualization of areas with known defects in the sample. The experimental results demonstrated the identification of defects such as empty holes, a hole filled with stucco, subsurface delaminations and natural features such as a wood knot and wood grain in different layers of the sample. For this wooden sample that has a very low thermal diffusivity, a depth range of 2 mm was achieved.

Photonic efficiency of the photodegradation of paracetamol in water by the photo-Fenton process.

Science.gov (United States)

Yamal-Turbay, E; Ortega, E; Conte, L O; Graells, M; Mansilla, H D; Alfano, O M; Pérez-Moya, M

2015-01-01

An experimental study of the homogeneous Fenton and photo-Fenton degradation of 4-amidophenol (paracetamol, PCT) is presented. For all the operation conditions evaluated, PCT degradation is efficiently attained by both Fenton and photo-Fenton processes. Also, photonic efficiencies of PCT degradation and mineralization are determined under different experimental conditions, characterizing the influence of hydrogen peroxide (H2O2) and Fe(II) on both contaminant degradation and sample mineralization. The maximum photonic degradation efficiencies for 5 and 10 mg L(-1) Fe(II) were 3.9 (H2O2 = 189 mg L(-1)) and 5 (H2O2 = 378 mg L(-1)), respectively. For higher concentrations of oxidant, H2O2 acts as a "scavenger" radical, competing in pollutant degradation and reducing the reaction rate. Moreover, in order to quantify the consumption of the oxidizing agent, the specific consumption of the hydrogen peroxide was also evaluated. For all operating conditions of both hydrogen peroxide and Fe(II) concentration, the consumption values obtained for Fenton process were always higher than the corresponding values observed for photo-Fenton. This implies a less efficient use of the oxidizing agent for dark conditions.

Effect of oxygen incorporation on the vibrational properties of Al{sub 0.2}Ga{sub 0.3}In{sub 0.5}P:Be films

Energy Technology Data Exchange (ETDEWEB)

Soubervielle-Montalvo, C., E-mail: csober22@gmail.com [Area de Computacion e Informatica, Facultad de Ingenieria, Universidad Autonoma de San Luis Potosi, Av. Dr. Manuel Nava 8, Zona Universitaria, C.P. 78290, San Luis Potosi, S.L.P (Mexico); Vital-Ochoa, O. [Area de Computacion e Informatica, Facultad de Ingenieria, Universidad Autonoma de San Luis Potosi, Av. Dr. Manuel Nava 8, Zona Universitaria, C.P. 78290, San Luis Potosi, S.L.P (Mexico); Anda, F. de [Instituto de Investigacion en Comunicacion Optica, Universidad Autonoma de San Luis Potosi, Av. Karakorum 1470, Lomas 4a Secc., C.P. 78210, San Luis Potosi, S.L.P. (Mexico); Vazquez-Cortes, D.; Rodriguez, A.G. [Coordinacion para la Innovacion y Aplicacion de la Ciencia y Tecnologia, Universidad Autonoma de San Luis Potosi, Av. Karakorum 1470, Lomas 4a Secc., C.P. 78210, San Luis Potosi, S.L.P. (Mexico); Melendez-Lira, M. [Physics Department, Centro de Investigacion y de Estudios Avanzados del IPN, Av. Instituto Politecnico Nacional 2508, San Pedro Zacatenco, C.P. 07360, Mexico, D.F. (Mexico); Mendez-Garcia, V.H. [Coordinacion para la Innovacion y Aplicacion de la Ciencia y Tecnologia, Universidad Autonoma de San Luis Potosi, Av. Karakorum 1470, Lomas 4a Secc., C.P. 78210, San Luis Potosi, S.L.P. (Mexico)

2011-10-31

The vibrational properties of Al{sub 0.2}Ga{sub 0.3}In{sub 0.5}P:Be films grown on (100) GaAs substrates by solid source molecular beam epitaxy varying the phosphorous cracking-zone temperature (PCT) were studied by Raman spectroscopy. The Raman-intensity ratio between the allowed longitudinal optical and the forbidden transverse optical (TO) phonons, and the full width at half maximum of their Lorentzian fits were used to characterize the crystalline quality of the films. The Raman spectra from the samples show changes in the shape and intensity of phonon resonances depending on the PCT variation, indicating that the disorder in the lattice increases with PCT. The increasing disorder is related to the inclusion of oxygen, which act as a non-intentional perturbing impurity in the lattice. In addition, a vibrational mode located at 598 cm{sup -1} related to a forbidden InP-like TO phonon resonance was correlated with oxygen-induced disorder. Photoluminescence at room temperature shows that the high inclusion of oxygen also deteriorates the optical properties of the samples, by introducing non-radiative recombination centers.

Suppression of Boride Formation in Transient Liquid Phase Bonding of Pairings of Parent Superalloy Materials with Different Compositions and Grain Structures and Resulting Mechanical Properties

Science.gov (United States)

Steuer, Susanne; Singer, Robert F.

2014-07-01

Two Ni-based superalloys, columnar grained Alloy 247 and single-crystal PWA1483, are joined by transient liquid phase bonding using an amorphous brazing foil containing boron as a melting point depressant. At lower brazing temperatures, two different morphologies of borides develop in both base materials: plate-like and globular ones. Their ratio to each other is temperature dependent. With very high brazing temperatures, the deleterious boride formation in Alloy 247 can be totally avoided, probably because the three-phase-field moves to higher alloying element contents. For the superalloy PWA1483, the formation of borides cannot be completely avoided at high brazing temperatures as incipient melting occurs. During subsequent solidification of these areas, Chinese-script-like borides precipitate. The mechanical properties (tensile tests at room and elevated temperatures and short-term creep rupture tests at elevated temperatures) for brazed samples without boride precipitation are very promising. Tensile strengths and creep times to 1 pct strain are comparable, respectively, higher than the ones of the weaker parent material for all tested temperatures and creep conditions (from 90 to 100 pct rsp. 175 to 250 pct).

Exxon Nuclear Company WREM-based generic PWR ECCS evaluation model. Appendix C to Volume II. Yankee Rowe example problem

International Nuclear Information System (INIS)

1975-01-01

Core 12, of the Yankee Rowe (YR), plant is to be licensed with the Exxon Nuclear Co. PWR Evaluation Model. This appendix presents methodology and results of an example calculation for the YR plant using the ENC Evaluation Model. This example problem is for the double-ended guillotine cold leg break with a discharge coefficient of 0.6 assuming loss of one emergency diesel. The NSSS supplier has determined this case to give the highest peak cladding temperature (PCT) for Core 11. The YR example problem was performed to determine the maximum acceptable local peak heating rate (Kw/ft). The blowdown was performed with beginning-of-cycle (BOC) ENC fuel at full power with the hot assembly power corresponding to the design peak rod heating rate of 12.9 Kw/ft. The HOT CHANNEL, TOODEE2, and RELAP4-FLOOD runs were made at several reduced hot assembly radial peaks, holding axial peaking constant, until an acceptable PCT was achieved. This procedure results in a PCT of 1834 0 F at a reduced peak linear heating rate of 10.5 Kw/ft for the ENC fuel at BOC. (auth)

The mineralogical characterization of tellurium in copper anodes

Science.gov (United States)

Chen, T. T.; Dutrizac, J. E.

1993-12-01

A mineralogical study of a «normal» commercial copper anode and six tellurium-rich copper anodes from the CCR Refinery of the Noranda Copper Smelting and Refining Company was carried out to identify the tellurium carriers and their relative abundances. In all the anodes, the major tellurium carrier is the Cu2Se-Cu2Te phase which occurs as a constituent of complex inclusions at the copper grain boundaries. In tellurium-rich anodes, the molar tellurium content of the Cu2Se-Cu2Te phase can exceed that of selenium. Although >85 pct of the tellurium occurs as the Cu2Se-Cu2Te phase, minor amounts are present in Cu-Pb-As-Bi-Sb oxide, Cu-Bi-As oxide, and Cu-Te-As oxide phases which form part of the grain-boundary inclusions. About 1 pct of the tellurium content of silver-rich anodes occurs in various silver alloys, but gold tellurides were never detected. Surprising is the fact that 2 to 8 pct of the total tellurium content of the anodes occurs in solid solution in the copper-metal matrix, and presumably, this form of tellurium dissolves at the anode interface during electrorefining.

The Effect of Aging on the Microstructure of Selective Laser Melted Cu-Ni-Si

Science.gov (United States)

Ventura, Anthony P.; Marvel, Christopher J.; Pawlikowski, Gregory; Bayes, Martin; Watanabe, Masashi; Vinci, Richard P.; Misiolek, Wojciech Z.

2017-12-01

Precipitation hardening copper alloy C70250 was selectively laser melted to successfully produce components around 98 pct dense with high mechanical strength and electrical conductivity. Aging heat treatments were carried out at 723 K (450 °C) directly on as-printed samples up to 128 hours. Mechanical testing found that peak yield strength of around 590 MPa could be attained with an electrical conductivity of 34.2 pct IACS after 8 hours of aging. Conductivity continues to increase with further aging while the peak strength appears to be less sensitive to aging time exhibiting a broad range of time where near-peak properties exist. After aging for 128 hours, there is a drop in yield strength to 546 MPa with an increase in conductivity to 43.2 pct IACS. Electron microscopy analysis revealed nanometer-scale silicon-rich oxide particles throughout the material that persist during aging. Deformation twinning is observed in the peak-age condition after tensile testing and several strengthening mechanisms appear to be active to varying degrees throughout aging which account for the broad range of aging time where nearly the peak mechanical properties exist.

Mechanism of Na2SO4 Promoting Nickel Extraction from Sulfide Concentrates by Sulfation Roasting-Water Leaching

Science.gov (United States)

Li, Guangshi; Cheng, Hongwei; Chen, Sha; Lu, Xionggang; Xu, Qian; Lu, Changyuan

2018-06-01

As a more environmentally friendly and energy-efficient route, the sulfation roasting-water leaching technique has been developed for highly effective extraction of non-ferrous metals from nickel sulfide concentrate in the presence of a Na2SO4 additive. The effects of several important roasting parameters—the roasting temperature, the addition of Na2SO4, the holding time, and the heating rate in particular—have been investigated. The results suggest that about 90 pct Ni, 92 pct Co, 95 pct Cu, and leached from the calcine roasted under the optimum conditions. Furthermore, the behavior and mechanism of the Na2SO4 additive in the roasting process have been well addressed by detailed characterization of the roasted product and leaching residue using quantitative phase analysis (QPA) and energy dispersive spectroscopy (EDS) mapping. The Na2SO4 additive was observed to play a noticeable role in promoting the sulfation degree of valuable metals by forming liquid phases [Na2Me(SO4)2] at the outermost layer, which can create a suitable dynamic environment for sulfation. Thus, addition of Na2SO4 might be conducive to an alternative metallurgical process involving complex sulfide ores.

Thermoelastic martensite and shape memory effect in ductile Cu-Al-Mn alloys

Science.gov (United States)

Kainuma, R.; Takahashi, S.; Ishida, K.

1996-08-01

Ductile shape memory (SM) alloys of the Cu-AI-Mn system have been developed by controlling the degree of order in the β phase. Additions of Mn to the binary Cu-Al alloy stabilize the β phase and widen the single-phase region to lower temperature and lower Al contents. It is shown that Cu-Al-Mn alloys with low Al contents have either the disordered A2 structure or the ordered L21 structure with a lower degree of order and that they exhibit excellent ductility. The disordered A2 phase martensitically transforms to the disordered Al phase with a high density of twins. The martensite phase formed from the ordered L21 phase has the 18R structure. The SM effect accompanies both the A2 → Al and L21 → 18R martensitic transformations. These alloys exhibit 15 pct strain to failure, 60 to 90 pct rolling reduction without cracking, and 80 to 90 pct recovery from bend test in the martensitic condition. Experimental results on the microstructure, crystal structure, mechanical properties, and shape memory behavior in the ductile Cu-AI-Mn alloys are presented and discussed.

Computed tomography in the treatment of cervical spinal cord tumors

International Nuclear Information System (INIS)

Shin, Hideo

1984-01-01

Computed tomography (CT) of the cervical and thoracic spinal column was carried out in 12 patients of spinal cord tumor. There were 6 schwannomas, 2 metastatic tumors and other 4 cases of different tumors, which were studied by either a General Electric CT/T or a Toshiba TCT 60 Type A scanner. In all patients, CT-examination followed conventional spinal X-ray studies. The usefulness of the plain spinal CT (PCT: CT without any contrast enhancement neither intravenously nor intrathecally) was to detect subtle bony changes as well as paraspinal soft tissue abnormalities, although it was hard to distinguish the spinal cord by PCT. Metrizamide CT myelography (CTM: CT with intrathecal instillation of metrizamide) was indispensable to identify the intracanalicular architecture. It provided the clue to determine the site and the size of tumor, and it was also useful after surgical procedure. CTM with intravenous contrast enhancement (CTM-CE) together with CTM distinguished the spinal tumor from the spinal cord very well, particularly in the cases of schwannoma. The author supports significant reliability of PCT, CTM and CTM-CE in identifying the presence, the extension and the bony involvement of spinal cord tumors. (author)

X-ray photoelectron spectroscopy, depth profiling, and elemental imaging of metal/polyimide interfaces of high density interconnect packages subjected to temperature and humidity

International Nuclear Information System (INIS)

Jung, David R.; Ibidunni, Bola; Ashraf, Muhammad

1998-01-01

X-ray photoelectron spectroscopy (XPS) was used to analyze surfaces and buried interfaces of a tape ball grid array (TBGA) interconnect package that was exposed to temperature and humidity testing (the pressure cooker test or PCT). Two metallization structures, employing 3.5 and 7.5 nm Cr adhesion layers, respectively, showed dramatically different results in the PCT. For the metallization with 3.5 nm Cr, spontaneous failure occurred on the polymer side of the metal/polyimide interface. Copper and other metals were detected by XPS on and below this polymer surface. For the metallization with 7.5 nm Cr, which did not delaminate in the PCT, the metallization was manually peeled away and also showed failure at the polymer side of the interface. Conventional XPS taken from a 1 mm diameter area showed the presence of metals on and below this polymer surface. Detailed spatially-resolved analysis using small area XPS (0.1 mm diameter area) and imaging XPS (7 μm resolution) showed that this metal did not migrate through and below the metal/polymer interface, but around and outside of the metallized area

CMOS Active Pixel Sensors as energy-range detectors for proton Computed Tomography

International Nuclear Information System (INIS)

Esposito, M.; Waltham, C.; Allinson, N.M.; Anaxagoras, T.; Evans, P.M.; Poludniowski, G.; Green, S.; Parker, D.J.; Price, T.; Manolopoulos, S.; Nieto-Camero, J.

2015-01-01

Since the first proof of concept in the early 70s, a number of technologies has been proposed to perform proton CT (pCT), as a means of mapping tissue stopping power for accurate treatment planning in proton therapy. Previous prototypes of energy-range detectors for pCT have been mainly based on the use of scintillator-based calorimeters, to measure proton residual energy after passing through the patient. However, such an approach is limited by the need for only a single proton passing through the energy-range detector in a read-out cycle. A novel approach to this problem could be the use of pixelated detectors, where the independent read-out of each pixel allows to measure simultaneously the residual energy of a number of protons in the same read-out cycle, facilitating a faster and more efficient pCT scan. This paper investigates the suitability of CMOS Active Pixel Sensors (APSs) to track individual protons as they go through a number of CMOS layers, forming an energy-range telescope. Measurements performed at the iThemba Laboratories will be presented and analysed in terms of correlation, to confirm capability of proton tracking for CMOS APSs

CMOS Active Pixel Sensors as energy-range detectors for proton Computed Tomography.

Science.gov (United States)

Esposito, M; Anaxagoras, T; Evans, P M; Green, S; Manolopoulos, S; Nieto-Camero, J; Parker, D J; Poludniowski, G; Price, T; Waltham, C; Allinson, N M

2015-06-03

Since the first proof of concept in the early 70s, a number of technologies has been proposed to perform proton CT (pCT), as a means of mapping tissue stopping power for accurate treatment planning in proton therapy. Previous prototypes of energy-range detectors for pCT have been mainly based on the use of scintillator-based calorimeters, to measure proton residual energy after passing through the patient. However, such an approach is limited by the need for only a single proton passing through the energy-range detector in a read-out cycle. A novel approach to this problem could be the use of pixelated detectors, where the independent read-out of each pixel allows to measure simultaneously the residual energy of a number of protons in the same read-out cycle, facilitating a faster and more efficient pCT scan. This paper investigates the suitability of CMOS Active Pixel Sensors (APSs) to track individual protons as they go through a number of CMOS layers, forming an energy-range telescope. Measurements performed at the iThemba Laboratories will be presented and analysed in terms of correlation, to confirm capability of proton tracking for CMOS APSs.

Glass formation and properties in the gallia-calcia system

Science.gov (United States)

Whichard, G.; Day, D. E.

1984-01-01

The critical cooling rate for glass formation was measured for five compositions in the Ga2O3-CaO system and varied from a low of (315 + or - 85) C/s for a eutectic melt containing 37.5 mol pct Ga2O3 to a high of (840 + or - 60) C/s for a melt containing 52 mol pct Ga2O3. The density and refractive index both increased with increasing Ga2O3 content, but the crystallization temperature and microhardness varied only slightly. The IR spectra of these glasses suggest that both GaO4 tetrahedra and GaO6 octahedra are present.

Diagnostic utility of procalcitonin versus C-reactive protein as markers for early-onset neonatal sepsis at Korle-Bu Teaching Hospital

DEFF Research Database (Denmark)

Amponsah, Seth Kwabena; Adjei, George Obeng; Sulley, Abdul Malik

2017-01-01

'' group compared to 31.6% (6/19) in the ''probable group'' (p5 mg/L was 54.4% (12/22) in the ''highly probable'' group compared to 26.3% (5/19) in the ''probable group'' (p = 0.07). The receiver operator characteristics for PCT and CRP were; sensitivity (87.5% vrs 50......%), specificity (63.0% vrs 72.2%), positive predictive value (44.1% vrs 37.5%) and negative predictive value (93.8% vrs 81.3%), respectively. Conclusion: PCT was a better predictive marker for neonatal sepsis within the first 12 hours of life than CRP in this setting, however, its low specificity relative to CRP...

Removal of radon by aeration: testing of various aeration techniques for small water works. For European Commission under Contract No FI4PCT960054 TENAWA project

International Nuclear Information System (INIS)

Salonen, L.; Mehtonen, J.; Turunen, H.; Mjoenes, L.; Hagberg, N.; Raff, O.

2002-12-01

Capability of various aeration techniques to remove radon from water in small waterworks was studied as a part of project (Treatment Techniques for Removing Natural Radionuclides from Drinking Water), which was carried out during 1997-1999 on a cost-shared basis (contract No. F14PCT960054) with The European Commission (CEC) under the supervision of the Directorate-General XII Radiation Protection Research Unit. In TENAWA project both laboratory and field experiments were performed in order to find reliable methods and equipment for removing natural radionuclides from ground water originating either from private wells or small waterworks. Because such techniques are more often needed in private households than at waterworks, the main emphasis of the research was aimed to solve the water treatment problems related to the private water supplies, especially bedrock wells. Radon was the most important radionuclide to be removed from water at waterworks whereas the removal of other radionuclides ( 234,238 U, 226,228 Ra, 210 Pb and 210 Po) was oft required from radonrich bedrock waters. The currently available methods and equipment were mainly tested during the field and laboratory experiments but the project was also aimed to find new materials, absorbents and membranes applicable for radionuclide removal from various types of ground waters (e.g. soft, hard, acidic). Because iron, manganese or organic occur in waters with radionuclides, their simultaneous removal was also studied. The project was divided into 13 work packages. In this report the results of the work package 2.2 are described. Elevated levels of radon and other natural radionuclides in European ground waters have been observed mainly in wide areas of the crystalline Scandinavian bedrock, especially in the granite rock areas of Finland and Sweden but also in more limited crystalline rock areas of Central and Southern Europe, Ukraine and Scotland. The radon removal efficiencies of different aeration methods

Usefulness of estimation of blood procalcitonin concentration versus C-reactive protein concentration and white blood cell count for therapeutic monitoring of sepsis in neonates

Directory of Open Access Journals (Sweden)

Agnieszka Kordek

2014-12-01

Full Text Available Aim: This study was intended to assess the clinical usefulness of blood procalcitonin (PCT concentrations for the diagnosis and therapeutic monitoring of nosocomial neonatal sepsis.Material/Methods: The enrolment criterion was sepsis clinically manifesting after three days of life. PCT concentrations were measured in venous blood from 52 infected and 88 uninfected neonates. The results were interpreted against C-reactive protein (CRP concentrations and white blood cell counts (WBC.Results: Differences between the two groups in PCT and CRP concentrations were highly significant. No significant differences between the groups were noted for WBC. The threshold value on the receiver operator characteristic curve was 2.06 ng/mL for PCT (SE 75%; SP 80.68%; PPV 62.22%; NPV 88.75%; AUC 0.805, 5.0 mg/L for CRP (SE 67.44%; SP 73.68%; PPV 42.02%; NPV 88.89%; AUC 0.801, and 11.9 x109/L for WBC (SE 51.16%; SP 50.68%; PPV 23.16%; NPV 78.13%; AUC 0.484. Procalcitonin concentrations decreased 24 hours after initiation of antibiotic therapy and reverted to the control level after 5-7 days. C-reactive protein concentrations began to decline after two days of antibiotic therapy but were still higher than in the control group after 5-7 days of treatment. No significant changes in WBC during the treatment were observed.Conclusions: Procalcitonin concentrations in blood appear to be of use for the diagnosis and therapeutic monitoring of nosocomial infections in neonates as this parameter demonstrates greater sensitivity and specificity than C-reactive protein. White blood cell counts appear to be of little diagnostic value in the early phase of infection or for therapeutic monitoring.

Mechanism and Influencing Factors of Iron Nuggets Forming in Rotary Hearth Furnace Process at Lower Temperature

Science.gov (United States)

Han, Hongliang; Duan, Dongping; Chen, Siming; Yuan, Peng

2015-10-01

In order to improve the efficiency of slag and iron separation, a new idea of "the separation of slag (solid state) and iron (molten state) in rotary hearth furnace process at lower temperature" is put forward. In this paper, the forming process of iron nuggets has been investigated. Based on those results, the forming mechanisms and influencing factors of iron nugget at low temperature are discussed experimentally using an electric resistance furnace simulating a rotary hearth furnace process. Results show that the reduction of iron ore, carburization of reduced iron, and the composition and quantity of slag are very important for producing iron nuggets at lower temperature. Reduction reaction of carbon-containing pellets is mainly at 1273 K and 1473 K (1000 °C and 1200 °C). When the temperature is above 1473 K (1200 °C), the metallization rate of carbon-containing pellets exceeds 93 pct, and the reduction reaction is substantially complete. Direct carburization is the main method for carburization of reduced iron. This reaction occurs above 1273 K (1000 °C), with carburization degree increasing greatly at 1473 K and 1573 K (1200 °C and 1300 °C) after particular holding times. Besides, to achieve the "slag (solid state) and iron (molten state) separation," the melting point of the slag phase should be increased. Slag (solid state) and iron (molten state) separation can be achieved below 1573 K (1300 °C), and when the holding time is 20 minutes, C/O is 0.7, basicity is less than 0.5 and a Na2CO3 level of 3 pct, the recovery rate of iron can reach 90 pct, with a proportion of iron nuggets more than 3.15 mm of nearly 90 pct. This study can provide theoretical and technical basis for iron nugget production.

Relationships between central and peripheral corneal thickness in different degrees of myopia.

Science.gov (United States)

Ortiz, Sara; Mena, Laura; Rio-San Cristobal, Ana; Martin, Raul

2014-01-01

To analyze the relationship between the central corneal thickness (CCT) and mid-peripheral corneal thickness (PCT) with the degree of myopia [axial length (AL) and spherical equivalent refractive error (SE)]. 175 right myopic eyes from 175 patients were divided according to the degree of SE: group #1 (n=76, 12.00 D). The CCT and PCT (3mm from the apex to the superior, inferior, nasal and temporal locations) were measured with the Orbscan-II. Relative peripheral index (RPI) was calculated by dividing the PCT by the CCT. The AL was measured with the IOL Master, and the SE was obtained with subjective refraction. AL was 25.18±1.16 mm, 26.59±1.26 mm and 29.45±2.58 mm and SE was -3.31±1.40 D, -8.32±1.64 D and -16.44±4.48 D for groups #1, #2 and #3, respectively. Non-statistically significant differences in central and peripheral corneal thickness were found between groups (P>0.05 ANOVA). Non-significant relationship was found between central and peripheral corneal thickness with the AL and SE in the three study groups and in the total sample (r0.05). The RPI values were similar between groups without significant difference between groups (P>0.05 ANOVA). Linear relationship was found between RPI superior location in group #2 (r=-0.23; P=0.04) and RPI nasal location in group #3 with the EE (r=0.41; P=0.03). There are no significant differences among low, moderate and extremely myopic eyes related to the CCT and PCT. Corneal thickness is very similar in myopic eyes with small differences that are not clinically relevant to myopic patient management. Copyright © 2012 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

Perfusion-CT guided intravenous thrombolysis in patients with unknown-onset stroke: a randomized, double-blind, placebo-controlled, pilot feasibility trial.

Science.gov (United States)

Michel, Patrik; Ntaios, George; Reichhart, Marc; Schindler, Christian; Bogousslavsky, Julien; Maeder, Philip; Meuli, Reto; Wintermark, Max

2012-06-01

Patients with unknown stroke onset are generally excluded from acute recanalisation treatments. We designed a pilot study to assess feasibility of a trial of perfusion computed tomography (PCT)-guided thrombolysis in patients with ischemic tissue at risk of infarction and unknown stroke onset. Patients with a supratentorial stroke of unknown onset in the middle cerebral artery territory and significant volume of at-risk tissue on PCT were randomized to intravenous thrombolysis with alteplase (0.9 mg/kg) or placebo. Feasibility endpoints were randomization and blinded treatment of patients within 2 h after hospital arrival, and the correct application (estimation) of the perfusion imaging criteria. At baseline, there was a trend towards older age [69.5 (57-78) vs. 49 (44-78) years] in the thrombolysis group (n = 6) compared to placebo (n = 6). Regarding feasibility, hospital arrival to treatment delay was above the allowed 2 h in three patients (25%). There were two protocol violations (17%) regarding PCT, both underestimating the predicted infarct in patients randomized in the placebo group. No symptomatic hemorrhage or death occurred during the first 7 days. Three of the four (75%) and one of the five (20%) patients were recanalized in the thrombolysis and placebo group respectively. The volume of non-infarcted at-risk tissue was 84 (44-206) cm(3) in the treatment arm and 29 (8-105) cm(3) in the placebo arm. This pilot study shows that a randomized PCT-guided thrombolysis trial in patients with stroke of unknown onset may be feasible if issues such as treatment delays and reliable identification of tissue at risk of infarction tissue are resolved. Safety and efficiency of such an approach need to be established.

Retention of differentiated characteristics by cultures of defined rabbit kidney epithelia.

Science.gov (United States)

Wilson, P D; Anderson, R J; Breckon, R D; Nathrath, W; Schrier, R W

1987-02-01

Rabbit nephron segments of proximal convoluted tubules (PCT); proximal straight tubules (PST); cortical and medullary thick ascending limbs of Henle's loop (CAL, MAL); and cortical, outer medullary, and inner medullary collecting tubules (CCT, OMCT, IMCT) were individually microdissected and grown in monolayer culture in hormone supplemented, defined media. Factors favoring a rapid onset of proliferation included young donor age, distal tubule origin, and the addition of 3% fetal calf serum to the medium. All primary cultures had polarized morphology with apical microvilli facing the medium and basement membrane-like material adjacent to the dish. Differentiated properties characteristic of the tubular epithelium of origin retained in cultures included ultrastructural characteristics and cytochemically demonstrable marker enzyme proportions. PCT and PST were rich in alkaline phosphatase; CAL stained strongly for NaK-ATPase; CCT contained two cell populations with regard to cytochrome oxidase reaction. A CCT-specific anti-keratin antibody (aLEA) was immunolocalized in CCT cultures, and a PST cytokeratin antibody stained PST cultures. The biochemical response of adenylate cyclase to putative stimulating agents was the same in primary cultures as in freshly isolated tubules. In PCT and PST adenylate cyclase activity was stimulated by parathyroid hormone (PTH) but not by arginine vasopressin (AVP); CAL and MAL adenylate cyclase was stimulated by neither PTH nor AVP; CCT, OMCT, and IMCT adenylate cyclase was stimulated by AVP but not by PTH. NaF stimulated adenylate cyclase activity in every cultured segment. It is concluded that primary cultures of individually microdissected rabbit PCT, PST, CAL, MAL, CCT, OMCT, and IMCT retain differentiated characteristics with regard to ultrastructure, marker enzymes, cytoskeletal proteins, and hormone response of adenylate cyclase and provide a new system for studying normal and abnormal functions of the heterogeneous tubular

Impact of Martensite Spatial Distribution on Quasi-Static and Dynamic Deformation Behavior of Dual-Phase Steel

Science.gov (United States)

Singh, Manpreet; Das, Anindya; Venugopalan, T.; Mukherjee, Krishnendu; Walunj, Mahesh; Nanda, Tarun; Kumar, B. Ravi

2018-02-01

The effects of microstructure parameters of dual-phase steels on tensile high strain dynamic deformation characteristic were examined in this study. Cold-rolled steel sheets were annealed using three different annealing process parameters to obtain three different dual-phase microstructures of varied ferrite and martensite phase fraction. The volume fraction of martensite obtained in two of the steels was near identical ( 19 pct) with a subtle difference in its spatial distribution. In the first microstructure variant, martensite was mostly found to be situated at ferrite grain boundaries and in the second variant, in addition to at grain boundaries, in-grain martensite was also observed. The third microstructure was very different from the above two with respect to martensite volume fraction ( 67 pct) and its morphology. In this case, martensite packets were surrounded by a three-dimensional ferrite network giving an appearance of core and shell type microstructure. All the three steels were tensile deformed at strain rates ranging from 2.7 × 10-4 (quasi-static) to 650 s-1 (dynamic range). Field-emission scanning electron microscope was used to characterize the starting as well as post-tensile deformed microstructures. Dual-phase steel consisting of small martensite volume fraction ( 19 pct), irrespective of its spatial distribution, demonstrated high strain rate sensitivity and on the other hand, steel with large martensite volume fraction ( 67 pct) displayed a very little strain rate sensitivity. Interestingly, total elongation was found to increase with increasing strain rate in the dynamic regime for steel with core-shell type of microstructure containing large martensite volume fraction. The observed enhancement in plasticity in dynamic regime was attributed to adiabatic heating of specimen. To understand the evolving damage mechanism, the fracture surface and the vicinity of fracture ends were studied in all the three dual-phase steels.

Noise texture and signal detectability in propagation-based x-ray phase-contrast tomography

International Nuclear Information System (INIS)

Chou, Cheng-Ying; Anastasio, Mark A.

2010-01-01

Purpose: X-ray phase-contrast tomography (PCT) is a rapidly emerging imaging modality for reconstructing estimates of an object's three-dimensional x-ray refractive index distribution. Unlike conventional x-ray computed tomography methods, the statistical properties of the reconstructed images in PCT remain unexplored. The purpose of this work is to quantitatively investigate noise propagation in PCT image reconstruction. Methods: The authors derived explicit expressions for the autocovariance of the reconstructed absorption and refractive index images to characterize noise texture and understand how the noise properties are influenced by the imaging geometry. Concepts from statistical detection theory were employed to understand how the imaging geometry-dependent statistical properties affect the signal detection performance in a signal-known-exactly/background-known-exactly task. Results: The analytical formulas for the phase and absorption autocovariance functions were implemented numerically and compared to the corresponding empirical values, and excellent agreement was found. They observed that the reconstructed refractive images are highly spatially correlated, while the absorption images are not. The numerical results confirm that the strength of the covariance is scaled by the detector spacing. Signal detection studies were conducted, employing a numerical observer. The detection performance was found to monotonically increase as the detector-plane spacing was increased. Conclusions: The authors have conducted the first quantitative investigation of noise propagation in PCT image reconstruction. The reconstructed refractive images were found to be highly spatially correlated, while absorption images were not. This is due to the presence of a Fourier space singularity in the reconstruction formula for the refraction images. The statistical analysis may facilitate the use of task-based image quality measures to further develop and optimize this emerging

Noise texture and signal detectability in propagation-based x-ray phase-contrast tomography

Energy Technology Data Exchange (ETDEWEB)

Chou, Cheng-Ying; Anastasio, Mark A. [Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei, Taiwan 106, Taiwan (China); Department of Biomedical Engineering, Medical Imaging Research Center, Illinois Institute of Technology, 3440 S. Dearborn Street, E1-116, Chicago, Illinois 60616 (United States)

2010-01-15

Purpose: X-ray phase-contrast tomography (PCT) is a rapidly emerging imaging modality for reconstructing estimates of an object's three-dimensional x-ray refractive index distribution. Unlike conventional x-ray computed tomography methods, the statistical properties of the reconstructed images in PCT remain unexplored. The purpose of this work is to quantitatively investigate noise propagation in PCT image reconstruction. Methods: The authors derived explicit expressions for the autocovariance of the reconstructed absorption and refractive index images to characterize noise texture and understand how the noise properties are influenced by the imaging geometry. Concepts from statistical detection theory were employed to understand how the imaging geometry-dependent statistical properties affect the signal detection performance in a signal-known-exactly/background-known-exactly task. Results: The analytical formulas for the phase and absorption autocovariance functions were implemented numerically and compared to the corresponding empirical values, and excellent agreement was found. They observed that the reconstructed refractive images are highly spatially correlated, while the absorption images are not. The numerical results confirm that the strength of the covariance is scaled by the detector spacing. Signal detection studies were conducted, employing a numerical observer. The detection performance was found to monotonically increase as the detector-plane spacing was increased. Conclusions: The authors have conducted the first quantitative investigation of noise propagation in PCT image reconstruction. The reconstructed refractive images were found to be highly spatially correlated, while absorption images were not. This is due to the presence of a Fourier space singularity in the reconstruction formula for the refraction images. The statistical analysis may facilitate the use of task-based image quality measures to further develop and optimize this emerging

Artesunate Suppositories versus Intramuscular Artemether for Treatment of Severe Malaria in Children in Papua New Guinea

Science.gov (United States)

Karunajeewa, Harin A.; Reeder, John; Lorry, Kerry; Dabod, Elizah; Hamzah, Juliana; Page-Sharp, Madhu; Chiswell, Gregory M.; Ilett, Kenneth F.; Davis, Timothy M. E.

2006-01-01

Drug treatment of severe malaria must be rapidly effective. Suppositories may be valuable for childhood malaria when circumstances prevent oral or parenteral therapy. We compared artesunate suppositories (n = 41; 8 to 16 mg/kg of body weight at 0 and 12 h and then daily) with intramuscular (i.m.) artemether (n = 38; 3.2 mg/kg at 0 h and then 1.6 mg/kg daily) in an open-label, randomized trial with children with severe Plasmodium falciparum malaria in Papua New Guinea (PNG). Parasite density and temperature were measured every 6 h for ≥72 h. Primary endpoints included times to 50% and 90% parasite clearance (PCT50 and PCT90) and the time to per os status. In a subset of 29 patients, plasma levels of artemether, artesunate, and their common active metabolite dihydroartemisinin were measured during the first 12 h. One suppository-treated patient with multiple complications died within 2 h of admission, but the remaining 78 recovered uneventfully. Compared to the artemether-treated children, those receiving artesunate suppositories had a significantly earlier mean PCT50 (9.1 versus 13.8 h; P = 0.008) and PCT90 (15.6 versus 20.4 h; P = 0.011). Mean time to per os status was similar for each group. Plasma concentrations of primary drug plus active metabolite were significantly higher in the artesunate suppository group at 2 h postdose. The earlier initial fall in parasitemia with artesunate is clinically advantageous and mirrors higher initial plasma concentrations of active drug/metabolite. In severely ill children with malaria in PNG, artesunate suppositories were at least as effective as i.m. artemether and may, therefore, be useful in settings where parenteral therapy cannot be given. PMID:16495259

Artesunate suppositories versus intramuscular artemether for treatment of severe malaria in children in Papua New Guinea.

Science.gov (United States)

Karunajeewa, Harin A; Reeder, John; Lorry, Kerry; Dabod, Elizah; Hamzah, Juliana; Page-Sharp, Madhu; Chiswell, Gregory M; Ilett, Kenneth F; Davis, Timothy M E

2006-03-01

Drug treatment of severe malaria must be rapidly effective. Suppositories may be valuable for childhood malaria when circumstances prevent oral or parenteral therapy. We compared artesunate suppositories (n = 41; 8 to 16 mg/kg of body weight at 0 and 12 h and then daily) with intramuscular (i.m.) artemether (n = 38; 3.2 mg/kg at 0 h and then 1.6 mg/kg daily) in an open-label, randomized trial with children with severe Plasmodium falciparum malaria in Papua New Guinea (PNG). Parasite density and temperature were measured every 6 h for > or = 72 h. Primary endpoints included times to 50% and 90% parasite clearance (PCT50 and PCT90) and the time to per os status. In a subset of 29 patients, plasma levels of artemether, artesunate, and their common active metabolite dihydroartemisinin were measured during the first 12 h. One suppository-treated patient with multiple complications died within 2 h of admission, but the remaining 78 recovered uneventfully. Compared to the artemether-treated children, those receiving artesunate suppositories had a significantly earlier mean PCT50 (9.1 versus 13.8 h; P = 0.008) and PCT90 (15.6 versus 20.4 h; P = 0.011). Mean time to per os status was similar for each group. Plasma concentrations of primary drug plus active metabolite were significantly higher in the artesunate suppository group at 2 h postdose. The earlier initial fall in parasitemia with artesunate is clinically advantageous and mirrors higher initial plasma concentrations of active drug/metabolite. In severely ill children with malaria in PNG, artesunate suppositories were at least as effective as i.m. artemether and may, therefore, be useful in settings where parenteral therapy cannot be given.

Infection biomarkers in primary care patients with acute respiratory tract infections-comparison of Procalcitonin and C-reactive protein.

Science.gov (United States)

Meili, Marc; Kutz, Alexander; Briel, Matthias; Christ-Crain, Mirjam; Bucher, Heiner C; Mueller, Beat; Schuetz, Philipp

2016-03-24

There is a lack of studies comparing the utility of C-reactive protein (CRP) with Procalcitonin (PCT) for the management of patients with acute respiratory tract infections (ARI) in primary care. Our aim was to study the correlation between these markers and to compare their predictive accuracy in regard to clinical outcome prediction. This is a secondary analysis using clinical and biomarker data of 458 primary care patients with pneumonic and non-pneumonic ARI. We used correlation statistics (spearman's rank test) and multivariable regression models to assess association of markers with adverse outcome, namely days with restricted activities and persistence of discomfort from infection at day 14. At baseline, CRP and PCT did not correlate well in the overall population (r(2) = 0.16) and particularly in the subgroup of patients with non-pneumonic ARI (r(2) = 0.08). Low correlation of biomarkers were also found when comparing cut-off ranges, day seven levels or changes from baseline to day seven. High baseline levels of CRP (>100 mg/dL, regression coefficient 1.6, 95 % CI 0.5 to 2.6, sociodemographic-adjusted model) as well as PCT (>0.5ug/L regression coefficient 2.0, 95 % CI 0.0 to 4.0, sociodemographic-adjusted model) were significantly associated with larger number of days with restricted activities. There were no associations of either biomarker with persistence of discomfort at day 14. CRP and PCT levels do not well correlate, but both have moderate prognostic accuracy in primary care patients with ARI to predict clinical outcomes. The low correlation between the two biomarkers calls for interventional research comparing these markers head to head in regard to their ability to guide antibiotic decisions. Current Controlled Trials, ISRCTN73182671.

Perfusion-CT guided intravenous thrombolysis in patients with unknown-onset stroke: a randomized, double-blind, placebo-controlled, pilot feasibility trial

International Nuclear Information System (INIS)

Michel, Patrik; Ntaios, George; Reichhart, Marc; Schindler, Christian; Bogousslavsky, Julien; Maeder, Philip; Meuli, Reto; Wintermark, Max

2012-01-01

Patients with unknown stroke onset are generally excluded from acute recanalisation treatments. We designed a pilot study to assess feasibility of a trial of perfusion computed tomography (PCT)-guided thrombolysis in patients with ischemic tissue at risk of infarction and unknown stroke onset. Patients with a supratentorial stroke of unknown onset in the middle cerebral artery territory and significant volume of at-risk tissue on PCT were randomized to intravenous thrombolysis with alteplase (0.9 mg/kg) or placebo. Feasibility endpoints were randomization and blinded treatment of patients within 2 h after hospital arrival, and the correct application (estimation) of the perfusion imaging criteria. At baseline, there was a trend towards older age [69.5 (57-78) vs. 49 (44-78) years] in the thrombolysis group (n = 6) compared to placebo (n = 6). Regarding feasibility, hospital arrival to treatment delay was above the allowed 2 h in three patients (25%). There were two protocol violations (17%) regarding PCT, both underestimating the predicted infarct in patients randomized in the placebo group. No symptomatic hemorrhage or death occurred during the first 7 days. Three of the four (75%) and one of the five (20%) patients were recanalized in the thrombolysis and placebo group respectively. The volume of non-infarcted at-risk tissue was 84 (44-206) cm 3 in the treatment arm and 29 (8-105) cm 3 in the placebo arm. This pilot study shows that a randomized PCT-guided thrombolysis trial in patients with stroke of unknown onset may be feasible if issues such as treatment delays and reliable identification of tissue at risk of infarction tissue are resolved. Safety and efficiency of such an approach need to be established. (orig.)

Systematic review of studies generating individual participant data on the efficacy of drugs for treating soil-transmitted helminthiases and the case for data-sharing.

Science.gov (United States)

Halder, Julia B; Benton, Joanne; Julé, Amélie M; Guérin, Phillipe J; Olliaro, Piero L; Basáñez, María-Gloria; Walker, Martin

2017-10-01

Preventive chemotherapy and transmission control (PCT) by mass drug administration is the cornerstone of the World Health Organization (WHO)'s policy to control soil-transmitted helminthiases (STHs) caused by Ascaris lumbricoides (roundworm), Trichuris trichiura (whipworm) and hookworm species (Necator americanus and Ancylostama duodenale) which affect over 1 billion people globally. Despite consensus that drug efficacies should be monitored for signs of decline that could jeopardise the effectiveness of PCT, systematic monitoring and evaluation is seldom implemented. Drug trials mostly report aggregate efficacies in groups of participants, but heterogeneities in design complicate classical meta-analyses of these data. Individual participant data (IPD) permit more detailed analysis of drug efficacies, offering increased sensitivity to identify atypical responses potentially caused by emerging drug resistance. We performed a systematic literature review to identify studies concluding after 2000 that collected IPD suitable for estimating drug efficacy against STH. We included studies that administered a variety of anthelmintics with follow ups less than 60 days after treatment. We estimated the number of IPD and extracted cohort- and study-level meta-data. We estimate that there exist individual data on approximately 35,000 participants from 129 studies conducted in 39 countries, including 34 out of 103 countries where PCT is recommended. We find significant heterogeneity in diagnostic methods, times of outcome assessment, and the reported measure of efficacy. We also quantify cohorts comprising pre-school age children, pregnant women, and co-infected participants, including with HIV. We argue that establishing a global IPD repository would improve the capacity to monitor and evaluate the efficacy of anthelmintic drugs, respond to changes and safeguard the ongoing effectiveness of PCT. Establishing a fair, transparent data governance policy will be key for the

Systematic review of studies generating individual participant data on the efficacy of drugs for treating soil-transmitted helminthiases and the case for data-sharing.

Directory of Open Access Journals (Sweden)

Julia B Halder

2017-10-01

Full Text Available Preventive chemotherapy and transmission control (PCT by mass drug administration is the cornerstone of the World Health Organization (WHO's policy to control soil-transmitted helminthiases (STHs caused by Ascaris lumbricoides (roundworm, Trichuris trichiura (whipworm and hookworm species (Necator americanus and Ancylostama duodenale which affect over 1 billion people globally. Despite consensus that drug efficacies should be monitored for signs of decline that could jeopardise the effectiveness of PCT, systematic monitoring and evaluation is seldom implemented. Drug trials mostly report aggregate efficacies in groups of participants, but heterogeneities in design complicate classical meta-analyses of these data. Individual participant data (IPD permit more detailed analysis of drug efficacies, offering increased sensitivity to identify atypical responses potentially caused by emerging drug resistance.We performed a systematic literature review to identify studies concluding after 2000 that collected IPD suitable for estimating drug efficacy against STH. We included studies that administered a variety of anthelmintics with follow ups less than 60 days after treatment. We estimated the number of IPD and extracted cohort- and study-level meta-data.We estimate that there exist individual data on approximately 35,000 participants from 129 studies conducted in 39 countries, including 34 out of 103 countries where PCT is recommended. We find significant heterogeneity in diagnostic methods, times of outcome assessment, and the reported measure of efficacy. We also quantify cohorts comprising pre-school age children, pregnant women, and co-infected participants, including with HIV.We argue that establishing a global IPD repository would improve the capacity to monitor and evaluate the efficacy of anthelmintic drugs, respond to changes and safeguard the ongoing effectiveness of PCT. Establishing a fair, transparent data governance policy will be key for

Integrated clinical and quality improvement coaching in Son La Province, Vietnam: a model of building public sector capacity for sustainable HIV care delivery.

Science.gov (United States)

Cosimi, Lisa A; Dam, Huong V; Nguyen, Thai Q; Ho, Huyen T; Do, Phuong T; Duc, Duat N; Nguyen, Huong T; Gardner, Bridget; Libman, Howard; Pollack, Todd; Hirschhorn, Lisa R

2015-07-17

The global scale-up of antiretroviral therapy included extensive training and onsite support to build the capacity of HIV health care workers. However, traditional efforts aimed at strengthening knowledge and skills often are not successful at improving gaps in the key health systems required for sustaining high quality care. We trained and mentored existing staff of the Son La provincial health department and provincial HIV clinic to work as a provincial coaching team (PCT) to provide integrated coaching in clinical HIV skills and quality improvement (QI) to the HIV clinics in the province. Nine core indicators were measured through chart extraction by clinic and provincial staff at baseline and at 6 month intervals thereafter. Coaching from the team to each of the clinics, in both QI and clinical skills, was guided by results of performance measurements, gap analyses, and resulting QI plans. After 18 months, the PCT had successfully spread QI activities, and was independently providing regular coaching to the provincial general hospital clinic and six of the eight district clinics in the province. The frequency and type of coaching was determined by performance measurement results. Clinics completed a mean of five QI projects. Quality of HIV care was improved throughout all clinics with significant increases in seven of the indicators. Overall both the PCT activities and clinic performance were sustained after integration of the model into the Vietnam National QI Program. We successfully built capacity of a team of public sector health care workers to provide integrated coaching in both clinical skills and QI across a province. The PCT is a feasible and effective model to spread and sustain quality activities and improve HIV care services in a decentralized rural setting.

In Situ Study of Microstructure Evolution in Solidification of Hypereutectic Al-Si Alloys with Application of Thermal Analysis and Neutron Diffraction

Science.gov (United States)

Sediako, Dimitry G.; Kasprzak, Wojciech

2015-09-01

Understanding of the kinetics of solid-phase evolution in solidification of hypereutectic aluminum alloys is a key to control their as-cast microstructure and resultant mechanical properties, and in turn, to enhance the service characteristics of actual components. This study was performed to evaluate the solidification kinetics for three P-modified hypereutectic Al-19 pct Si alloys: namely, Al-Si binary alloy and with the subsequent addition of 2.8 pct Cu and 2.8 pct Cu + 0.7 pct Mg. Metallurgical evaluation included thermodynamic calculations of the solidification process using the FactSage™ 6.2 software package, as well as experimental thermal analysis, and in situ neutron diffraction. The study revealed kinetics of solid α-Al, solid Si, Al2Cu, and Mg2Si evolution, as well as the individual effects of Cu and Mg alloying additions on the solidification path of the Al-Si system. Various techniques applied in this study resulted in some discrepancies in the results. For example, the FactSage computations, in general, resulted in 281 K to 286 K (8 °C to 13 °C) higher Al-Si eutectic temperatures than the ones recorded in the thermal analysis, which are also ~278 K (~5 °C) higher than those observed in the in situ neutron diffraction. None of the techniques can provide a definite value for the solidus temperature, as this is affected by the chosen calculation path [283 K to 303 K (10 °C to 30 °C) higher for equilibrium solidification vs non-equilibrium] for the FactSage analysis; and further complicated by evolution of secondary Al-Cu and Mg-Si phases that commenced at the end of solidification. An explanation of the discrepancies observed and complications associated with every technique applied is offered in the paper.

Detection of serum procalcitonin levels in children with bacterial or viral meningitis%儿童细菌性或病毒性脑膜炎患者血清降钙素原的检测

Institute of Scientific and Technical Information of China (English)

卢勤红; 王家学

2016-01-01

目的 通过检测疑似儿童细菌性或病毒性脑膜炎患者血清降钙素原(procalcitonin,PCT),并与血清C-反应蛋白(C-reactive protein,CRP)比较,以确定降钙素原在脑膜炎鉴别诊断中的作用.方法 95例疑似细菌性或病毒性脑膜炎患儿,分成细菌性脑膜炎组(56例)和病毒性脑膜炎组(39例),分别检测2组患者刚入院和治疗3d后血清PCT和CRP,并对结果进行统计学分析.结果 刚入院患儿血清PCT和CRP,细菌性脑膜炎组均明显高于病毒性脑膜炎组,差异有统计学意义(P＜0.01).治疗3d后细菌性脑膜炎组血清PCT明显降低,差异有统计学意义(P＜0.01),而病毒性脑膜炎组血清PCT与刚人院相比,差异无统计学意义(P＞0.05).研究血清PCT和CRP不同界值时对细菌性脑膜炎诊断结果,发现随设置界值的增高,诊断的敏感度降低、特异度增高.结论 血清PCT可作为儿童细菌性脑膜炎和病毒性脑膜炎鉴别诊断的重要指标.%Objective By detecting serum proealcitonin(PCT) levels from the suspected children with bacterial or viral meningitis,and compared to serum C-reactive protein(CRP),to study the role of pr6cálcitonin in the diagnosis and identification of meningitis.Methods 95 children with suspected meningitis were classified into two groups:the bacterial meningitis group(56 cases) and the viral meningitis group(39 cases).PCT and CRP of the two groups were measured at the time of admission and after 3 days,and the results were statistically analyzed.Results The serum PCT and CRP at admission in the bacterial menin gitis group were significantly higher than that in the viral meningitis group,and the difference was statistically significant(P ＜0.01).PCT levels in bacterial meningitis group obviously decreased after 3 days of treatment,and the difference was statistically significant(P ＜0.01).However,there was no statistical significance on the difference in the serum PCT of viral meningitis group,compared with

Densification kinetics and structure formation during the high-pressure sintering of Al2O3-TiN powder systems

Energy Technology Data Exchange (ETDEWEB)

Neshpor, V.S.; Barashkov, G.A.; Nikitiuk, A.F.

1986-04-01

Specimens of alumina of varying specific surface and a composite material containing 80 pct alpha-Al2O3 and 20 pct TiN were sintered at 5 GPa for 30-480 s in the temperature range 1650-1750 K. It is found that the densification process is particularly intensive during the first 30-60 s. Under the conditions investigated, alpha-Al2O3 powder exhibits higher densification rates and final density (100 percent) than the ultradisperse TiN powder, whose final density is 96 percent. The results of the study suggest that densification is achieved through particle fragmentation and slip. Noticeable grain growth is observed for alumina only when the sintering time exceeds 2 min. 7 references.

Path connectivity based spectral defragmentation in flexible bandwidth networks.

Science.gov (United States)

Wang, Ying; Zhang, Jie; Zhao, Yongli; Zhang, Jiawei; Zhao, Jie; Wang, Xinbo; Gu, Wanyi

2013-01-28

Optical networks with flexible bandwidth provisioning have become a very promising networking architecture. It enables efficient resource utilization and supports heterogeneous bandwidth demands. In this paper, two novel spectrum defragmentation approaches, i.e. Maximum Path Connectivity (MPC) algorithm and Path Connectivity Triggering (PCT) algorithm, are proposed based on the notion of Path Connectivity, which is defined to represent the maximum variation of node switching ability along the path in flexible bandwidth networks. A cost-performance-ratio based profitability model is given to denote the prons and cons of spectrum defragmentation. We compare these two proposed algorithms with non-defragmentation algorithm in terms of blocking probability. Then we analyze the differences of defragmentation profitability between MPC and PCT algorithms.

Crystallization and characterization of Y2O3-SiO2 glasses

Science.gov (United States)

Drummond, Charles H., III; Lee, William E.; Sanders, W. A.; Kiser, J. D.

1991-01-01

Glasses in the yttria-silica system with 20 to 40 mol pct Y2O3 were subjected to recrystallization studies after melting at 1900 to 2100 C in W crucibles in 1 and 50 atm N2. The TEM and XRD results obtained indicate the presence of the delta, gamma, gamma prime, and beta-Y2Si2O7 crystalline phases, depending on melting and quenching conditions. Heat treatment in air at 1100 to 1600 C increased the amount of crystallization, and led to the formation of Y2SiO5, cristabalite, and polymorphs of Y2Si2O7. Also investigated were the effects of 5 and 10 wt pct zirconia additions.

Development of Duplex Stainless Steels by Field-Assisted Hot Pressing: Influence of the Particle Size and Morphology of the Powders on the Final Mechanical Properties

Science.gov (United States)

García-Junceda, A.; Rincón, M.; Torralba, J. M.

2018-01-01

The feasibility of processing duplex stainless steels with promising properties using a powder metallurgical route, including the consolidation by field-assisted hot pressing, is assessed in this investigation. The influence of the particle size and morphology of the raw austenitic and ferritic powders on the final microstructure and properties is also evaluated for an austenitic content of 60 wt pct. In addition, the properties of a new microconstituent generated between the initial constituents are analyzed. The maximum sintered density (98.9 pct) and the best mechanical behavior, in terms of elastic modulus, nanohardness, yield strength, ultimate tensile strength, and ductility, are reached by the duplex stainless steel processed with austenitic and ferritic gas atomized stainless steel powders.

Delamination of Pearlitic Steel Wires: The Defining Role of Prior-Drawing Microstructure

Science.gov (United States)

Durgaprasad, A.; Giri, S.; Lenka, S.; Sarkar, Sudip Kumar; Biswas, Aniruddha; Kundu, S.; Mishra, S.; Chandra, S.; Doherty, R. D.; Samajdar, I.

2018-03-01

This article reports the occasional (alignment of the pearlite: 22 ± 5 pct vs 34 ± 4 pct in the nondelaminated wires. Although all wires had similar through-thickness texture and stress gradients, delaminated wires had stronger gradients in composition and higher hardness across the ferrite-cementite interface. Carbide dissolution and formation of supersaturated ferrite were clearly correlated with delamination, which could be effectively mitigated by controlled laboratory annealing at 673 K. Direct observations on samples subjected to simple shear revealed significant differences in shear localizations. These were controlled by pearlite morphology and interlamellar spacing. Prior-drawing microstructure of coarse misaligned pearlite thus emerged as a critical factor in the wire drawing-induced delamination of the pearlitic wires.

An Introduction to the IP/PCT Model Implementation in IPME

Science.gov (United States)

2011-03-01

of rudder pedals and toe brakes is a compatible combination that would be added to the exception list. Table 4. Task interference coefficients...visual angle ; • those problems associated with operating spatially separated controls with the same hand or limb; and • the inability to speak two...certain angle (say 30˚) of visual arc, will not be detected — or will be detected with a certain probability (see Table 7) — and therefore may not be

Mechanical Behavior of Additively Manufactured Uranium-6 wt. pct. Niobium

Energy Technology Data Exchange (ETDEWEB)

Wu, A. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wraith, M. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Burke, S. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hamza, A. V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brown, D. W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Clausen, B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hsiung, L. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McKeown, J. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lindvall, R. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sedillo, E. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Teslich, N. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Torres, S. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Urabe, D. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Freeman, D. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alexander, P. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Iniguez, M. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ryerson, F. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ancheta, D. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lotscher, J. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Young, E. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Evans, C. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Florando, J. N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gallegos, G. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Margraff, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hrousis, C. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Campbell, G. H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-09-15

This report describes an effort to process uranium-6 weight% niobium using laser powder bed fusion. The chemistry, crystallography, microstructure and mechanical response resulting from this process are discussed with particular emphasis on the effect of the laser powder bed fusion process on impurities. In an effort to achieve homogenization and uniform mechanical behavior from different builds, as well as to induce a more conventional loading response, we explore post-processing heat treatments on this complex alloy. Elevated temperature heat treatment for recrystallization is evaluated and the effect of recrystallization on mechanical behavior in laser powder bed fusion processed U-6Nb is discussed. Wrought-like mechanical behavior and grain sizes are achieved through post-processing and are reported herein.

The distribution of dark matter, galaxies, and the intergalactic medium in a cold dark matter dominated universe

Science.gov (United States)

Ryu, Dongsu; Vishniac, Ethan T.; Chiang, Wei-Hwan

1988-01-01

The evolution and distribution of galaxies and the intergalactic medium (IGM) have been studied, along with collisionless dark matter in a Universe dominated by cold dark matter. The Einstein-deSitter universe with omega sub 0 = 1 and h = 0.5 was considered (here h = H sub 0 bar 100/kms/Mpc and H sub 0 is the present value of the Hubble constant). It is assumed that initially dark matter composes 90 pct and baryonic matter composes 10 pct of total mass, and that the primordial baryonic matter is comprised of H and He, with the abundance of He equal to 10 pct of H by number. Galaxies are allowed to form out of the IGM, if the total density and baryonic density satisfy an overdensity criterion. Subsequently, the newly formed galaxies release 10 to the 60th ergs of energy into the IGM over a period of 10 to the 8th years. Calculations have been performed with 32 to the 3rd dark matter particles and 32 to the 3rd cells in a cube with comoving side length L = 9.6/h Mpc. Dark matter particles and galaxies have been followed with an N-body code, while the IGM has been followed with a fluid code.

Enhanced Densification of PM Steels by Liquid Phase Sintering with Boron-Containing Master Alloy

Science.gov (United States)

Vattur Sundaram, Maheswaran; Surreddi, Kumar Babu; Hryha, Eduard; Veiga, Angela; Berg, Sigurd; Castro, Fransisco; Nyborg, Lars

2018-01-01

Reaching high density in PM steels is important for high-performance applications. In this study, liquid phase sintering of PM steels by adding gas-atomized Ni-Mn-B master alloy was investigated for enhancing the density levels of Fe- and Mo- prealloyed steel powder compacts. The results indicated that liquid formation occurs in two stages, beginning with the master alloy melting (LP-1) below and eutectic phase formation (LP-2) above 1373 K (1100 °C). Mo and C addition revealed a significant influence on the LP-2 temperatures and hence on the final densification behavior and mechanical properties. Microstructural embrittlement occurs with the formation of continuous boride networks along the grain boundaries, and its severity increases with carbon addition, especially for 2.5 wt pct of master alloy content. Sintering behavior, along with liquid generation, microstructural characteristics, and mechanical testing revealed that the reduced master alloy content from 2.5 to 1.5 wt pct (reaching overall boron content from 0.2 to 0.12 wt pct) was necessary for obtaining good ductility with better mechanical properties. Sintering with Ni-Mn-B master alloy enables the sintering activation by liquid phase formation in two stages to attain high density in PM steels suitable for high-performance applications.

Short-term consistency testing vs. long-term behavior

International Nuclear Information System (INIS)

Ebert, W.L.; Bakel, A.J.; Wolf, S.F.; Strachan, D.M.

1997-01-01

The authors conducted Product Consistency Tests (PCTs) with a surrogate low-activity waste (LAW) glass to (1) evaluate the possible use of various test conditions in a specification test for LAW waste forms, (2) measure the reproducibility of the test at low temperatures, and (3) determine if the rates calculated from 7-day PCTs bound the rates measured in PCT conducted for longer durations, which represent more advanced corrosion. The effects of temperature and pH on the dissolution rate in PCTs are much less than the effects observed in dilute solutions due to the buildup of dissolved glass components in the PCTs. The precision of replicate 7-day tests at 20 and 40 degrees C was limited by the analytical uncertainty. The dissolution rates at all temperatures decreased with the test duration initially. However, the dissolution rates in tests at 70 and 90 degrees C increased when certain alteration phases formed after about 100 and 500 days, respectively; the rates in some tests exceeded that measured in a 7-day PCT. While the 7-day PCT does not provide a bounding rate for this glass at 70 or 90 degrees C, tests for longer durations are needed to determine if a 7-day test provides a bounding rate at lower temperatures