The unfolding effects on the protein hydration shell and partial molar volume: a computational study.

Science.gov (United States)

Del Galdo, Sara; Amadei, Andrea

2016-10-12

In this paper we apply the computational analysis recently proposed by our group to characterize the solvation properties of a native protein in aqueous solution, and to four model aqueous solutions of globular proteins in their unfolded states thus characterizing the protein unfolded state hydration shell and quantitatively evaluating the protein unfolded state partial molar volumes. Moreover, by using both the native and unfolded protein partial molar volumes, we obtain the corresponding variations (unfolding partial molar volumes) to be compared with the available experimental estimates. We also reconstruct the temperature and pressure dependence of the unfolding partial molar volume of Myoglobin dissecting the structural and hydration effects involved in the process.

Partial molar volumes of hydrogen and deuterium in niobium, vanadium, and tantalum

International Nuclear Information System (INIS)

Peterson, D.T.; Herro, H.M.

1983-01-01

The partial molar volumes of hydrogen and deuterium were measured in vanadium, niobium, and tantalum by a differential pressure technique. One-half of an electrolytically charged sample plat was compressed between hardened steel blocks in a hydraulic press. The activity of hydrogen in the hig pressure region was raised and caused hydrogen to diffuse into the low pressure region. The partia molar volume was calculated from the ratio of the hydrogen concentrations in the high and low pressure regions of the sample. Small isotope effects were found in the partial molar volume. Hydrogen had the larger volume in niobium and tantalum, but the reverse was true in vanadium

Excess molar volumes and partial molar volumes for (propionitrile + an alkanol) at T = 298.15 K and p = 0.1 MPa

International Nuclear Information System (INIS)

Deenadayalu, N.; Bhujrajh, P.

2006-01-01

The excess molar volumes and the partial molar volumes for (propionitrile + an alkanol) at T = 298.15 K and at atmospheric pressure are reported. The hydrogen bonding between the OH133;NC groups are discussed in terms of the chain length of the alkanol. The alkanols studied are (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 1-pentanol). The excess molar volume data was fitted to the Redlich-Kister equation The partial molar volumes were calculated from the Redlich-Kister coefficients

Partial drift volume due to a self-propelled swimmer

Science.gov (United States)

Chisholm, Nicholas G.; Khair, Aditya S.

2018-01-01

We assess the ability of a self-propelled swimmer to displace a volume of fluid that is large compared to its own volume via the mechanism of partial drift. The swimmer performs rectilinear locomotion in an incompressible, unbounded Newtonian fluid. The partial drift volume D is the volume of fluid enclosed between the initial and final profiles of an initially flat circular disk of marked fluid elements; the disk is initially aligned perpendicular to the direction of locomotion and subsequently distorted due to the passage of the swimmer, which travels a finite distance. To focus on the possibility of large-scale drift, we model the swimmer simply as a force dipole aligned with the swimming direction. At zero Reynolds number (Re =0 ), we demonstrate that D grows without limit as the radius of the marked fluid disk h is made large, indicating that a swimmer at Re =0 can generate a partial drift volume much larger than its own volume. Next, we consider a steady swimmer at small Re , which is modeled as the force-dipole solution to Oseen's equation. Here, we find that D no longer diverges with h , which is due to inertial screening of viscous forces, and is effectively proportional to the magnitude of the force dipole exerted by the swimmer. The validity of this result is extended to Re ≥O (1 ) —the realm of intermediate-Re swimmers such as copepods—by taking advantage of the fact that, in this case, the flow is also described by Oseen's equations at distances much larger than the characteristic linear dimension of the swimmer. Next, we utilize an integral momentum balance to demonstrate that our analysis for a steady inertial swimmer also holds, in a time-averaged sense, for an unsteady swimmer that does not experience a net acceleration over a stroke cycle. Finally, we use experimental data to estimate D for a few real swimmers. Interestingly, we find that D depends heavily on the kinematics of swimming, and, in certain cases, D can be significantly greater

Anatomically guided voxel-based partial volume effect correction in brain PET : Impact of MRI segmentation

NARCIS (Netherlands)

Gutierrez, Daniel; Montandon, Marie-Louise; Assal, Frederic; Allaoua, Mohamed; Ratib, Osman; Loevblad, Karl-Olof; Zaidi, Habib

2012-01-01

Partial volume effect is still considered one of the main limitations in brain PET imaging given the limited spatial resolution of current generation PET scanners. The accuracy of anatomically guided partial volume effect correction (PVC) algorithms in brain PET is largely dependent on the

Different partial volume correction methods lead to different conclusions

DEFF Research Database (Denmark)

Greve, Douglas N; Salat, David H; Bowen, Spencer L

2016-01-01

A cross-sectional group study of the effects of aging on brain metabolism as measured with (18)F-FDG-PET was performed using several different partial volume correction (PVC) methods: no correction (NoPVC), Meltzer (MZ), Müller-Gärtner (MG), and the symmetric geometric transfer matrix (SGTM) usin...

FMDP Reactor Alternative Summary Report: Volume 3 - partially complete LWR alternative

International Nuclear Information System (INIS)

Greene, S.R.; Fisher, S.E.; Bevard, B.B.

1996-09-01

The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 3 of a four volume report summarizes the results of these analyses for the partially complete LWR (PCLWR) reactor based plutonium disposition alternative

FMDP Reactor Alternative Summary Report: Volume 3 - partially complete LWR alternative

Energy Technology Data Exchange (ETDEWEB)

Greene, S.R.; Fisher, S.E.; Bevard, B.B. [and others

1996-09-01

The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 3 of a four volume report summarizes the results of these analyses for the partially complete LWR (PCLWR) reactor based plutonium disposition alternative.

Study of the seroma volume changes in the patients who underwent Accelerated Partial Breast Irradiation

International Nuclear Information System (INIS)

Kim, Dae Ho; Son, Sang Jun; Mun, Jun Ki; Seo, Seok Jin; Lee, Je Hee

2016-01-01

By analyzing seroma volume changes in the patients who underwent Partial breast radiation therapy after breast conserving surgery, we try to contribute to the improvement of radiotherapy effect. Enrolled 20 patients who underwent partial breast radiation therapy by ViewRay MRIdian System were subject. After seeking for the size of the removed sample in the patients during surgery and obtained seroma volume changes on a weekly basis. On the Basis of acquired volume, it was compared with age, term from start of the first treatment after surgery, BMI (body mass index) and the extracted sample size during surgery. And using the ViewRay MRIdian RTP System, the figure was analyzed by PTV(=seroma volume + margin) to obtain a specific volume of the Partial breast radiation therapy. The changes of seroma volume from MR simulation to the first treatment (a week) is 0~5% in 8, 5~10% in 3, 10 to 15% in 2, and 20% or more in 5 people. Two patients(A, B patient) among subjects showed the biggest change. The A patient's 100% of the prescribed dose volume is 213.08 cc, PTV is 181.93 cc, seroma volume is 15.3 cc in initial plan. However, while seroma volume decreased 65.36% to 5.3 cc, 100% of the prescribed dose volume was reduced to 3.4% to 102.43 cc and PTV also did 43.6% to 102.54 cc. In the case of the B patient, seroma volume decreased 42.57% from 20.2 cc to 11.6 cc. Because of that, 100% of the prescribed dose volume decreased 8.1% and PTV also did to 40%. As the period between the first therapy and surgery is shorter, the patient is elder and the size of sample is smaller than 100 cc, the change grow bigger. It is desirable to establish an adaptive plan according to each patient's changes of seroma volume through continuous observation. Because partial breast patients is more sensitive than WBRT patients about dose conformity in accordance with the volume change

Partial and apparent molar volumes of aqueous solutions of the 1:1 type electrolytes

International Nuclear Information System (INIS)

Klugman, I.Yu.

2002-01-01

Formulas for calculating partial and apparent molar volumes of MX (M=Li-Cs; X = Cl-I) electrolyte aqueous solutions in a wide range of concentrations from 0 to 4 mol/kg with error not in excess of 0.05% are suggested. It is shown that the previously employed formulas for calculating partial molar volumes of electrolytes give false indications of mutual effect of ions and actually they are fit solely for very small concentrations [ru

Whole object surface area and volume of partial-view 3D models

International Nuclear Information System (INIS)

Mulukutla, Gopal K; Proussevitch, Alexander A; Genareau, Kimberly D; Durant, Adam J

2017-01-01

Micro-scale 3D models, important components of many studies in science and engineering, are often used to determine morphological characteristics such as shape, surface area and volume. The application of techniques such as stereoscopic scanning electron microscopy on whole objects often results in ‘partial-view’ models with a portion of object not within the field of view thus not captured in the 3D model. The nature and extent of the surface not captured is dependent on the complex interaction of imaging system attributes (e.g. working distance, viewing angle) with object size, shape and morphology. As a result, any simplistic assumptions in estimating whole object surface area or volume can lead to significant errors. In this study, we report on a novel technique to estimate the physical fraction of an object captured in a partial-view 3D model of an otherwise whole object. This allows a more accurate estimate of surface area and volume. Using 3D models, we demonstrate the robustness of this method and the accuracy of surface area and volume estimates relative to true values. (paper)

Partial molar volume of n-alcohols at infinite dilution in water calculated by means of scaled particle theory.

Science.gov (United States)

Graziano, Giuseppe

2006-04-07

The partial molar volume of n-alcohols at infinite dilution in water is smaller than the molar volume in the neat liquid phase. It is shown that the formula for the partial molar volume at infinite dilution obtained from the scaled particle theory equation of state for binary hard sphere mixtures is able to reproduce in a satisfactory manner the experimental data over a large temperature range. This finding implies that the packing effects play the fundamental role in determining the partial molar volume at infinite dilution in water also for solutes, such as n-alcohols, forming H bonds with water molecules. Since the packing effects in water are largely related to the small size of its molecules, the latter feature is the ultimate cause of the decrease in partial molar volume associated with the hydrophobic effect.

Study of the seroma volume changes in the patients who underwent Accelerated Partial Breast Irradiation

Energy Technology Data Exchange (ETDEWEB)

Kim, Dae Ho; Son, Sang Jun; Mun, Jun Ki; Seo, Seok Jin; Lee, Je Hee [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

2016-06-15

By analyzing seroma volume changes in the patients who underwent Partial breast radiation therapy after breast conserving surgery, we try to contribute to the improvement of radiotherapy effect. Enrolled 20 patients who underwent partial breast radiation therapy by ViewRay MRIdian System were subject. After seeking for the size of the removed sample in the patients during surgery and obtained seroma volume changes on a weekly basis. On the Basis of acquired volume, it was compared with age, term from start of the first treatment after surgery, BMI (body mass index) and the extracted sample size during surgery. And using the ViewRay MRIdian RTP System, the figure was analyzed by PTV(=seroma volume + margin) to obtain a specific volume of the Partial breast radiation therapy. The changes of seroma volume from MR simulation to the first treatment (a week) is 0~5% in 8, 5~10% in 3, 10 to 15% in 2, and 20% or more in 5 people. Two patients(A, B patient) among subjects showed the biggest change. The A patient's 100% of the prescribed dose volume is 213.08 cc, PTV is 181.93 cc, seroma volume is 15.3 cc in initial plan. However, while seroma volume decreased 65.36% to 5.3 cc, 100% of the prescribed dose volume was reduced to 3.4% to 102.43 cc and PTV also did 43.6% to 102.54 cc. In the case of the B patient, seroma volume decreased 42.57% from 20.2 cc to 11.6 cc. Because of that, 100% of the prescribed dose volume decreased 8.1% and PTV also did to 40%. As the period between the first therapy and surgery is shorter, the patient is elder and the size of sample is smaller than 100 cc, the change grow bigger. It is desirable to establish an adaptive plan according to each patient's changes of seroma volume through continuous observation. Because partial breast patients is more sensitive than WBRT patients about dose conformity in accordance with the volume change.

Partial molar volume of proteins studied by the three-dimensional reference interaction site model theory.

Science.gov (United States)

Imai, Takashi; Kovalenko, Andriy; Hirata, Fumio

2005-04-14

The three-dimensional reference interaction site model (3D-RISM) theory is applied to the analysis of hydration effects on the partial molar volume of proteins. For the native structure of some proteins, the partial molar volume is decomposed into geometric and hydration contributions using the 3D-RISM theory combined with the geometric volume calculation. The hydration contributions are correlated with the surface properties of the protein. The thermal volume, which is the volume of voids around the protein induced by the thermal fluctuation of water molecules, is directly proportional to the accessible surface area of the protein. The interaction volume, which is the contribution of electrostatic interactions between the protein and water molecules, is apparently governed by the charged atomic groups on the protein surface. The polar atomic groups do not make any contribution to the interaction volume. The volume differences between low- and high-pressure structures of lysozyme are also analyzed by the present method.

Partial Molar Volume of Methanol in Water: Effect of Polarizability

Czech Academy of Sciences Publication Activity Database

Moučka, F.; Nezbeda, Ivo

2009-01-01

Roč. 74, č. 4 (2009), s. 559-563 ISSN 0010-0765 R&D Projects: GA AV ČR IAA400720802 Institutional research plan: CEZ:AV0Z40720504 Keywords : water–methanol mixtures * partial molar volume * polarizability Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.856, year: 2009

Note: Nonpolar solute partial molar volume response to attractive interactions with water

Energy Technology Data Exchange (ETDEWEB)

Williams, Steven M.; Ashbaugh, Henry S., E-mail: hanka@tulane.edu [Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118 (United States)

2014-01-07

The impact of attractive interactions on the partial molar volumes of methane-like solutes in water is characterized using molecular simulations. Attractions account for a significant 20% volume drop between a repulsive Weeks-Chandler-Andersen and full Lennard-Jones description of methane interactions. The response of the volume to interaction perturbations is characterized by linear fits to our simulations and a rigorous statistical thermodynamic expression for the derivative of the volume to increasing attractions. While a weak non-linear response is observed, an average effective slope accurately captures the volume decrease. This response, however, is anticipated to become more non-linear with increasing solute size.

Note: Nonpolar solute partial molar volume response to attractive interactions with water.

Science.gov (United States)

Williams, Steven M; Ashbaugh, Henry S

2014-01-07

The impact of attractive interactions on the partial molar volumes of methane-like solutes in water is characterized using molecular simulations. Attractions account for a significant 20% volume drop between a repulsive Weeks-Chandler-Andersen and full Lennard-Jones description of methane interactions. The response of the volume to interaction perturbations is characterized by linear fits to our simulations and a rigorous statistical thermodynamic expression for the derivative of the volume to increasing attractions. While a weak non-linear response is observed, an average effective slope accurately captures the volume decrease. This response, however, is anticipated to become more non-linear with increasing solute size.

Standard partial molar volumes of some electrolytes in ethylene carbonate based mixtures

International Nuclear Information System (INIS)

Zhao, Yang; Wang, Jianji.; Lu, Hui; Lin, Ruisen

2004-01-01

Apparent molar volumes V 2,phi and standard partial molar volumes V 2,phi 0 of LiClO 4 , LiBr and three symmetrical tetraalkylammonium bromides R 4 NBr (R=ethyl, propyl, butyl) have been determined at 298.15 K from precise density measurements in solvent mixtures of ethylene carbonate with tetrahydrofuran (THF), acetonitrile (AN), ethyl acetate (EA) and dimethoxyethane (DME). It is shown that the V 2,phi 0 values of LiClO 4 and LiBr are dependent strongly on the nature of the solvents, whereas the contribution of CH 2 group to the partial molar volume of the tetraalkylammonium salts has nothing to do with the nature of the solvents and the composition of the solvent mixtures. This provided a helpful evidence for the unsolvation of large tetraalkylammonium cations in organic solvents. The results have been discussed from ion-solvent interactions and the dielectric effect of the solvents

Effect of Molecular Size of Solutes on Their Partial Molar Volumes in Supercritical n-Pentane

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

The densities of n-pentane, methane-n-pentane, propane-n-pentane, n-heptane-n-pentane, and n-decane-n-pentane binary mixtures were determined at 476.5K in the pressure range from 2 to 5 MPa. The partial molar volumes of the solutes in n-pentane were calculated using the density data. It was found that the partial molar volumes of methane and propane are positive , while those of n-heptane and n-decane are negative.

Apparent CBF decrease with normal aging due to partial volume effects: MR-based partial volume correction on CBF SPECT.

Science.gov (United States)

Inoue, Kentaro; Ito, Hiroshi; Goto, Ryoi; Nakagawa, Manabu; Kinomura, Shigeo; Sato, Tachio; Sato, Kazunori; Fukuda, Hiroshi

2005-06-01

Several studies using single photon emission tomography (SPECT) have shown changes in cerebral blood flow (CBF) with age, which were associated with partial volume effects by some authors. Some studies have also demonstrated gender-related differences in CBF. The present study aimed to examine age and gender effects on CBF SPECT images obtained using the 99mTc-ethyl cysteinate dimer and a SPECT scanner, before and after partial volume correction (PVC) using magnetic resonance (MR) imaging. Forty-four healthy subjects (29 males and 15 females; age range, 27-64 y; mean age, 50.0 +/- 9.8 y) participated. Each MR image was segmented to yield grey and white matter images and coregistered to a corresponding SPECT image, followed by convolution to approximate the SPECT spatial resolution. PVC-SPECT images were produced using the convoluted grey matter MR (GM-MR) and white matter MR images. The age and gender effects were assessed using SPM99. Decreases with age were detected in the anterolateral prefrontal cortex and in areas along the lateral sulcus and the lateral ventricle, bilaterally, in the GM-MR images and the SPECT images. In the PVC-SPECT images, decreases in CBF in the lateral prefrontal cortex lost their statistical significance. Decreases in CBF with age found along the lateral sulcus and the lateral ventricle, on the other hand, remained statistically significant, but observation of the spatially normalized MR images suggests that these findings are associated with the dilatation of the lateral sulcus and lateral ventricle, which was not completely compensated for by the spatial normalization procedure. Our present study demonstrated that age effects on CBF in healthy subjects could reflect morphological differences with age in grey matter.

Determination of Partial Molar Volumes of EPA and DHA Ethyl Esters in Supercritical Carbon Dioxide

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

The use of supercritical-fluid chromatography for determining partial molar volumes of ethyl esters of cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and cis -4,7,10,13,16,19- docosa-hexaenoic acid (DHA) in supercritical carbon dioxide is presented and discussed. Partial molar volumes of EPA and DHA esters are obtained from the variation of the retention properties with the density of mobile phase at 313.15 K, 323.15 K, 333.15 K and in the pressure range from 9 MPa to 21 MPa.

Deptermination of Partial Molar Volumes of EPA and DHA Ethyl Esters in Supercritical Carbon Dioxide

Institute of Scientific and Technical Information of China (English)

MeiHUANG; XianDaWANG; 等

2002-01-01

The use of supercritical-fluid shromatogrphy for determining partial molar volumes of ethyl esters of cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and cis-4,7,10,13,16,19-docosa-hexaenoic acid(DHA) in supercritical carbon dioxide is presented and discussed. Partial molar volumes of EPA and DHA esters are obtained from the variation of the retention properties with the density of mobile phase at 313.15K,323.15K,333.15K and in the pressure range from 9 MPa to 21 MPa.

Analysis of Partial Volume Effects on Arterial Input Functions Using Gradient Echo: A Simulation Study

DEFF Research Database (Denmark)

Kjølby, Birgitte Fuglsang; Mikkelsen, Irene Klærke; Pedersen, Michael

2009-01-01

of an AIF voxel including the relaxation properties of blood and tissue. Artery orientations parallel and perpendicular to the main magnetic field were investigated and AIF voxels were modeled to either include or be situated close to a large artery. The impact of partial volume effects on quantitative...... perfusion metrics was investigated for the gradient echo pulse sequence at 1.5 T and 3.0 T. It is shown that the tissue contribution broadens and introduces fluctuations in the AIF. Furthermore, partial volume effects bias perfusion metrics in a nonlinear fashion, compromising quantitative perfusion...

Gastric residual volume (GRV) and gastric contents measurement by refractometry.

Science.gov (United States)

Chang, Wei-Kuo; McClave, Stephen A; Hsieh, Chung-Bao; Chao, You-Chen

2007-01-01

Traditional use of gastric residual volumes (GRVs), obtained by aspiration from a nasogastric tube, is inaccurate and cannot differentiate components of the gastric contents (gastric secretion vs delivered formula). The use of refractometry and 3 mathematical equations has been proposed as a method to calculate the formula concentration, GRV, and formula volume. In this paper, we have validated these mathematical equations so that they can be implemented in clinical practice. Each of 16 patients receiving a nasogastric tube had 50 mL of water followed by 100 mL of dietary formula (Osmolite HN, Abbott Laboratories, Columbus, OH) infused into the stomach. After mixing, gastric content was aspirated for the first Brix value (BV) measurement by refractometry. Then, 50 mL of water was infused into the stomach and a second BV was measured. The procedure of infusion of dietary formula (100 mL) and then water (50 mL) was repeated and followed by subsequent BV measurement. The same procedure was performed in an in vitro experiment. Formula concentration, GRV, and formula volume were calculated from the derived mathematical equations. The formula concentrations, GRVs, and formula volumes calculated by using refractometry and the mathematical equations were close to the true values obtained from both in vivo and in vitro validation experiments. Using this method, measurement of the BV of gastric contents is simple, reproducible, and inexpensive. Refractometry and the derived mathematical equations may be used to measure formula concentration, GRV, and formula volume, and also to serve as a tool for monitoring the gastric contents of patients receiving nasogastric feeding.

Partial molar volumes of some drug and pro-drug substances in 1-octanol at T = 298.15 K

International Nuclear Information System (INIS)

Manin, Alex N.; Shmukler, Liudmila E.; Safonova, Liubov P.; Perlovich, German L.

2010-01-01

The article deals with measuring the densities of phenol, acetanilide, benzamide, benzoic acid, phenacetin, i-(acetylamino)-benzoic acid, i-hydroxy-benzamide, and i-acetaminophen (where i = 1, 2, 3) in 1-octanol in the wide concentration interval at T = 298.15 K. It also concerns the evaluation of apparent molar volumes and partial molar volumes at infinite dilution, V 2 0 -bar as well as comparative analysis of the free volumes per molecule in the octanolic solutions, V 2 free , and in the crystal lattices, V 2 free (cr), from the nature and position of the substitutes. Also described is the evaluation of the increments of V 2 0 -bar andV 2 free for the unsubstituted molecules and isomers and the methods to obtain partial molar volumes for various functional groups at infinite dilution in 1-octanol at T = 298.15 K. Also considered is the limiting partial molar volume of the solutes in terms of the scaled particle theory.

Thermodynamic study of (heptane + amine) mixtures. II. Excess and partial molar volumes at 298.15 K

International Nuclear Information System (INIS)

Lepori, Luciano; Gianni, Paolo; Spanedda, Andrea; Matteoli, Enrico

2011-01-01

Research highlights: → Excess and partial molar volumes of primary (amines + heptane) mixtures. → Excess volumes are positive for small size amines and decrease as the size increases. → Group contributions to predict the partial molar volumes of amines in heptane. → The void volume is larger for branched than for linear amines in heptane. - Abstract: Excess molar volumes V E at 298.15 K were determined by means of a vibrating tube densimeter for binary mixtures of heptane + primary n-alkyl (C 3 to C 10 ) and branched amines (iso-propyl-, iso-, sec-, and tert-butyl-, iso-, tert-pentyl-, and pentan-3-amine) in the whole composition range. The apparent molar volumes of solid dodecyl- and tetradecylamine in heptane dilute solution were also determined. The V E values were found positive for mixtures involving C 3 to C 8 linear amines, with V E decreasing with chain lengthening. Heptane + nonyl and decylamine showed s-shaped, markedly asymmetric, curves. Mixtures with branched C 3 to C 5 amines displayed positive V E 's larger than those observed in the mixtures of the corresponding linear isomers. Partial molar volumes V o at infinite dilution in heptane were evaluated for the examined amines and compared with those of alkanes and alkanols taken from the literature. An additivity scheme, based on the intrinsic volume approach, was applied to estimate group (CH 3 , CH 2 , CH, C, NH 2 , and OH) contributions to V o . The effect of branching on V o and the limiting slope of the apparent excess molar volumes were evaluated and discussed in terms of solute-solvent and solute-solute interactions.

Genetic control of protein, oil and fatty acids content under partial ...

African Journals Online (AJOL)

The purpose of the present study was to map quantitative trait locus (QTLs) associated with percentage of seed protein, oil and fatty acids content under different conditions in a population of recombinant inbred lines (RILs) of sunflower. Three independent field experiments were conducted with well-, partial-irrigated and ...

Partial molar volume of anionic polyelectrolytes in aqueous solution.

Science.gov (United States)

Salamanca, Constain; Contreras, Martín; Gamboa, Consuelo

2007-05-15

In this work the partial molar volumes (V) of different anionic polyelectrolytes and hydrophobically modified polyelectrolytes (PHM) were measured. Polymers like polymaleic acid-co-styrene, polymaleic acid-co-1-olefin, polymaleic acid-co-vinyl-2-pyrrolidone, and polyacrylic acid (abbreviated as MAS-n, PA-n-K2, AMVP, and PAA, respectively) were employed. These materials were investigated by density measurements in highly dilute aqueous solutions. The molar volume results allow us to discuss the effect of the carboxylic groups and the contributions from the comonomeric principal chain. The PAA presents the smaller V, while the largest V value was for AMVP. The V of PHM shows a linear relationship with the number of methylene groups in the lateral chain. It is found that the magnitude of the contribution per methylene group decreases as the hydrophobic character of the environment increases.

On a relationship between molecular polarizability and partial molar volume in water.

Science.gov (United States)

Ratkova, Ekaterina L; Fedorov, Maxim V

2011-12-28

We reveal a universal relationship between molecular polarizability (a single-molecule property) and partial molar volume in water that is an ensemble property characterizing solute-solvent systems. Since both of these quantities are of the key importance to describe solvation behavior of dissolved molecular species in aqueous solutions, the obtained relationship should have a high impact in chemistry, pharmaceutical, and life sciences as well as in environments. We demonstrated that the obtained relationship between the partial molar volume in water and the molecular polarizability has in general a non-homogeneous character. We performed a detailed analysis of this relationship on a set of ~200 organic molecules from various chemical classes and revealed its fine well-organized structure. We found that this structure strongly depends on the chemical nature of the solutes and can be rationalized in terms of specific solute-solvent interactions. Efficiency and universality of the proposed approach was demonstrated on an external test set containing several dozens of polyfunctional and druglike molecules.

Partial molar volumes of some drug and pro-drug substances in 1-octanol at T = 298.15 K

Energy Technology Data Exchange (ETDEWEB)

Manin, Alex N.; Shmukler, Liudmila E.; Safonova, Liubov P. [Institute of Solution Chemistry, Russian Academy of Sciences, 153045 Ivanovo (Russian Federation); Perlovich, German L., E-mail: glp@isc-ras.r [Institute of Solution Chemistry, Russian Academy of Sciences, 153045 Ivanovo (Russian Federation)

2010-03-15

The article deals with measuring the densities of phenol, acetanilide, benzamide, benzoic acid, phenacetin, i-(acetylamino)-benzoic acid, i-hydroxy-benzamide, and i-acetaminophen (where i = 1, 2, 3) in 1-octanol in the wide concentration interval at T = 298.15 K. It also concerns the evaluation of apparent molar volumes and partial molar volumes at infinite dilution, V{sub 2}{sup 0}-bar as well as comparative analysis of the free volumes per molecule in the octanolic solutions, V{sub 2}{sup free}, and in the crystal lattices, V{sub 2}{sup free} (cr), from the nature and position of the substitutes. Also described is the evaluation of the increments of V{sub 2}{sup 0}-bar andV{sub 2}{sup free} for the unsubstituted molecules and isomers and the methods to obtain partial molar volumes for various functional groups at infinite dilution in 1-octanol at T = 298.15 K. Also considered is the limiting partial molar volume of the solutes in terms of the scaled particle theory.

Characterization of Volume F Trash from Four Recent STS Missions: Weights, Categorization, Water Content

Science.gov (United States)

Strayer, Richard F.; Hummerick, Mary E.; Richards, Jeffrey T.; McCoy, LaShelle E.; Roberts, Michael S.; Wheeler, Raymond M.

2011-01-01

The fate of space-generated solid wastes, including trash, for future missions is under consideration by NASA. Several potential treatment options are under consideration and active technology development. Potential fates for space-generated solid wastes are: Storage without treatment; storage after treatment(s) including volume reduction, water recovery, sterilization, and recovery plus recycling of waste materials. Recycling might be important for partial or full closure scenarios because of the prohibitive costs associated with resupply of consumable materials. For this study, we determined the composition of trash returned from four recent STS missions. The trash material was 'Volume F' trash and other trash, in large zip-lock bags, that accompanied the Volume F trash. This is the first of two submitted papers on these wastes. This one will cover trash content, weight and water content. The other will report on the microbial Characterization of this trash. STS trash was usually made available within 2 days of landing at KSC. The Volume F bag was weighed, opened and the contents were catalogued and placed into one of the following categories: food waste (and containers), drink containers, personal hygiene items - including EVA maximum absorbent garments (MAGs)and Elbow packs (daily toilet wipes, etc), paper, and packaging materials - plastic firm and duct tape. Trash generation rates for the four STS missions: Total wet trash was 0.602 plus or minus 0.089 kg(sub wet) crew(sup -1) d(sup -1) containing about 25% water at 0.154 plus or minus 0.030 kg(sub water) crew(sup -1) d(sup -1) (avg plus or minus stdev). Cataloguing by category: personal hygiene wastes accounted for 50% of the total trash and 69% of the total water for the four missions; drink items were 16% of total weight and 16% water; food wastes were 22% of total weight and 15% of the water; office waste and plastic film were 2% and 11% of the total waste and did not contain any water. The results can be

Quantitative analysis of CT brain images: a statistical model incorporating partial volume and beam hardening effects

International Nuclear Information System (INIS)

McLoughlin, R.F.; Ryan, M.V.; Heuston, P.M.; McCoy, C.T.; Masterson, J.B.

1992-01-01

The purpose of this study was to construct and evaluate a statistical model for the quantitative analysis of computed tomographic brain images. Data were derived from standard sections in 34 normal studies. A model representing the intercranial pure tissue and partial volume areas, with allowance for beam hardening, was developed. The average percentage error in estimation of areas, derived from phantom tests using the model, was 28.47%. We conclude that our model is not sufficiently accurate to be of clinical use, even though allowance was made for partial volume and beam hardening effects. (author)

Infinite dilution partial molar volumes of platinum(II) 2,4-pentanedionate in supercritical carbon dioxide.

Science.gov (United States)

Kong, Chang Yi; Siratori, Tomoya; Funazukuri, Toshitaka; Wang, Guosheng

2014-10-03

The effects of temperature and density on retention of platinum(II) 2,4-pentanedionate in supercritical fluid chromatography were investigated at temperatures of 308.15-343.15K and pressure range from 8 to 40MPa by the chromatographic impulse response method with curve fitting. The retention factors were utilized to derive the infinite dilution partial molar volumes of platinum(II) 2,4-pentanedionate in supercritical carbon dioxide. The determined partial molar volumes were small and positive at high pressures but exhibited very large and negative values in the highly compressible near critical region of carbon dioxide. Copyright © 2014 Elsevier B.V. All rights reserved.

Partial volume correction in SPECT reconstruction with OSEM

Energy Technology Data Exchange (ETDEWEB)

Erlandsson, Kjell, E-mail: k.erlandsson@ucl.ac.uk [Institute of Nuclear Medicine, University College London and University College London Hospital, London NW1 2BU (United Kingdom); Thomas, Ben; Dickson, John; Hutton, Brian F. [Institute of Nuclear Medicine, University College London and University College London Hospital, London NW1 2BU (United Kingdom)

2011-08-21

SPECT images suffer from poor spatial resolution, which leads to partial volume effects due to cross-talk between different anatomical regions. By utilising high-resolution structural images (CT or MRI) it is possible to compensate for these effects. Traditional partial volume correction (PVC) methods suffer from various limitations, such as correcting a single region only, returning only regional mean values, or assuming a stationary point spread function (PSF). We recently presented a novel method in which PVC was combined with the reconstruction process in order to take into account the distance dependent PSF in SPECT, which was based on filtered backprojection (FBP) reconstruction. We now present a new method based on the iterative OSEM algorithm, which has advantageous noise properties compared to FBP. We have applied this method to a series of 10 brain SPECT studies performed on healthy volunteers using the DATSCAN tracer. T1-weighted MRI images were co-registered to the SPECT data and segmented into 33 anatomical regions. The SPECT data were reconstructed using OSEM, and PVC was applied in the projection domain at each iteration. The correction factors were calculated by forward projection of a piece-wise constant image, generated from the segmented MRI. Images were also reconstructed using FBP and standard OSEM with and without resolution recovery (RR) for comparison. The images were evaluated in terms of striatal contrast and regional variability (CoV). The mean striatal contrast obtained with OSEM, OSEM-RR and OSEM-PVC relative to FBP were 1.04, 1.42 and 1.53, respectively, and the mean striatal CoV values are 1.05, 1.53, 1.07. Both OSEM-RR and OSEM-PVC results in images with significantly higher contrast as compared to FBP or OSEM, but OSEM-PVC avoids the increased regional variability of OSEM-RR due to improved structural definition.

A study of partial molar volumes of citric acid and tartaric acid

Indian Academy of Sciences (India)

Partial molar volumes of citric acid and tartaric acid have been determined in water and binary aqueous mixtures of ethanol (5, 10, 15, 20 and 25% by weight of ethanol) at different temperatures and acid concentrations from the solution density measurements. The data have been evaluated by using Masson equation and ...

Finite volume for three-flavour Partially Quenched Chiral Perturbation Theory through NNLO in the meson sector

International Nuclear Information System (INIS)

Bijnens, Johan; Rössler, Thomas

2015-01-01

We present a calculation of the finite volume corrections to meson masses and decay constants in three flavour Partially Quenched Chiral Perturbation Theory (PQChPT) through two-loop order in the chiral expansion for the flavour-charged (or off-diagonal) pseudoscalar mesons. The analytical results are obtained for three sea quark flavours with one, two or three different masses. We reproduce the known infinite volume results and the finite volume results in the unquenched case. The calculation has been performed using the supersymmetric formulation of PQChPT as well as with a quark flow technique. Partial analytical results can be found in the appendices. Some examples of cases relevant to lattice QCD are studied numerically. Numerical programs for all results are available as part of the CHIRON package.

Finite volume for three-flavour Partially Quenched Chiral Perturbation Theory through NNLO in the meson sector

Energy Technology Data Exchange (ETDEWEB)

Bijnens, Johan; Rössler, Thomas [Department of Astronomy and Theoretical Physics, Lund University,Sölvegatan 14A, SE 223-62 Lund (Sweden)

2015-11-16

We present a calculation of the finite volume corrections to meson masses and decay constants in three flavour Partially Quenched Chiral Perturbation Theory (PQChPT) through two-loop order in the chiral expansion for the flavour-charged (or off-diagonal) pseudoscalar mesons. The analytical results are obtained for three sea quark flavours with one, two or three different masses. We reproduce the known infinite volume results and the finite volume results in the unquenched case. The calculation has been performed using the supersymmetric formulation of PQChPT as well as with a quark flow technique. Partial analytical results can be found in the appendices. Some examples of cases relevant to lattice QCD are studied numerically. Numerical programs for all results are available as part of the CHIRON package.

Theoretical study of the partial molar volume change associated with the pressure-induced structural transition of ubiquitin.

Science.gov (United States)

Imai, Takashi; Ohyama, Shusaku; Kovalenko, Andriy; Hirata, Fumio

2007-09-01

The partial molar volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the volume of structural voids in the protein, which is partially canceled by the volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.

Finite-volume and partial quenching effects in the magnetic polarizability of the neutron

Science.gov (United States)

Hall, J. M. M.; Leinweber, D. B.; Young, R. D.

2014-03-01

There has been much progress in the experimental measurement of the electric and magnetic polarizabilities of the nucleon. Similarly, lattice QCD simulations have recently produced dynamical QCD results for the magnetic polarizability of the neutron approaching the chiral regime. In order to compare the lattice simulations with experiment, calculation of partial quenching and finite-volume effects is required prior to an extrapolation in quark mass to the physical point. These dependencies are described using chiral effective field theory. Corrections to the partial quenching effects associated with the sea-quark-loop electric charges are estimated by modeling corrections to the pion cloud. These are compared to the uncorrected lattice results. In addition, the behavior of the finite-volume corrections as a function of pion mass is explored. Box sizes of approximately 7 fm are required to achieve a result within 5% of the infinite-volume result at the physical pion mass. A variety of extrapolations are shown at different box sizes, providing a benchmark to guide future lattice QCD calculations of the magnetic polarizabilities. A relatively precise value for the physical magnetic polarizability of the neutron is presented, βn=1.93(11)stat(11)sys×10-4 fm3, which is in agreement with current experimental results.

Twisted finite-volume corrections to K{sub l3} decays with partially-quenched and rooted-staggered quarks

Energy Technology Data Exchange (ETDEWEB)

Bernard, Claude [Department of Physics, Washington University,One Brookings Drive, Saint Louis (United States); Bijnens, Johan [Department of Astronomy and Theoretical Physics, Lund University,Sölvegatan 14A, SE 223-62 Lund (Sweden); Gámiz, Elvira [CAFPE and Departamento de Física Teórica y del Cosmos, Universidad de Granada,Campus de Fuente Nueva, E-18002 Granada (Spain); Relefors, Johan [Department of Astronomy and Theoretical Physics, Lund University,Sölvegatan 14A, SE 223-62 Lund (Sweden)

2017-03-23

The determination of |V{sub us}| from kaon semileptonic decays requires the value of the form factor f{sub +}(q{sup 2}=0) which can be calculated precisely on the lattice. We provide the one-loop partially quenched chiral perturbation theory expressions both with and without including the effects of staggered quarks for all form factors at finite volume and with partially twisted boundary conditions for both the vector current and scalar density matrix elements at all q{sup 2}. We point out that at finite volume there are more form factors than just f{sub +} and f{sub −} for the vector current matrix element but that the Ward identity is fully satisfied. The size of the finite-volume corrections at present lattice sizes is small. This will help improve the lattice determination of f{sub +}(q{sup 2}=0) since the finite-volume error is the dominant error source for some calculations. The size of the finite-volume corrections may be estimated on a single lattice ensemble by comparing results for various twist choices.

White matter atlas of the human spinal cord with estimation of partial volume effect.

Science.gov (United States)

Lévy, S; Benhamou, M; Naaman, C; Rainville, P; Callot, V; Cohen-Adad, J

2015-10-01

Template-based analysis has proven to be an efficient, objective and reproducible way of extracting relevant information from multi-parametric MRI data. Using common atlases, it is possible to quantify MRI metrics within specific regions without the need for manual segmentation. This method is therefore free from user-bias and amenable to group studies. While template-based analysis is common procedure for the brain, there is currently no atlas of the white matter (WM) spinal pathways. The goals of this study were: (i) to create an atlas of the white matter tracts compatible with the MNI-Poly-AMU template and (ii) to propose methods to quantify metrics within the atlas that account for partial volume effect. The WM atlas was generated by: (i) digitalizing an existing WM atlas from a well-known source (Gray's Anatomy), (ii) registering this atlas to the MNI-Poly-AMU template at the corresponding slice (C4 vertebral level), (iii) propagating the atlas throughout all slices of the template (C1 to T6) using regularized diffeomorphic transformations and (iv) computing partial volume values for each voxel and each tract. Several approaches were implemented and validated to quantify metrics within the atlas, including weighted-average and Gaussian mixture models. Proof-of-concept application was done in five subjects for quantifying magnetization transfer ratio (MTR) in each tract of the atlas. The resulting WM atlas showed consistent topological organization and smooth transitions along the rostro-caudal axis. The median MTR across tracts was 26.2. Significant differences were detected across tracts, vertebral levels and subjects, but not across laterality (right-left). Among the different tested approaches to extract metrics, the maximum a posteriori showed highest performance with respect to noise, inter-tract variability, tract size and partial volume effect. This new WM atlas of the human spinal cord overcomes the biases associated with manual delineation and partial

Calculation of partial molar volume of components in supercritical ammonia synthesis system

Institute of Scientific and Technical Information of China (English)

Cunwen WANG; Chuanbo YU; Wen CHEN; Weiguo WANG; Yuanxin WU; Junfeng ZHANG

2008-01-01

The partial molar volumes of components in supercritical ammonia synthesis system are calculated in detail by the calculation formula of partial molar volume derived from the R-K equation of state under different conditions. The objectives are to comprehend phase beha-vior of components and to provide the theoretic explana-tion and guidance for probing novel processes of ammonia synthesis under supercritical conditions. The conditions of calculation are H2/N2= 3, at a concentra-tion of NH3 in synthesis gas ranging from 2% to 15%, Concentration of medium in supercritical ammonia syn-thesis system ranging from 20% to 50%, temperature ran-ging from 243 K to 699 K and pressure ranging from 0.1 MPa to 187 MPa. The results show that the ammonia synthesis system can reach supercritical state by adding a suitable supercritical medium and then controlling the reaction conditions. It is helpful for the supercritical ammonia synthesis that medium reaches supercritical state under the conditions of the corresponding total pres-sure and components near the normal temperature or near the critical temperature of medium or in the range of tem-perature of industrialized ammonia synthesis.

Hydrophobic hydration and the anomalous partial molar volumes in ethanol-water mixtures

International Nuclear Information System (INIS)

Tan, Ming-Liang; Te, Jerez; Cendagorta, Joseph R.; Miller, Benjamin T.; Brooks, Bernard R.; Ichiye, Toshiko

2015-01-01

The anomalous behavior in the partial molar volumes of ethanol-water mixtures at low concentrations of ethanol is studied using molecular dynamics simulations. Previous work indicates that the striking minimum in the partial molar volume of ethanol V E as a function of ethanol mole fraction X E is determined mainly by water-water interactions. These results were based on simulations that used one water model for the solute-water interactions but two different water models for the water-water interactions. This is confirmed here by using two more water models for the water-water interactions. Furthermore, the previous work indicates that the initial decrease is caused by association of the hydration shells of the hydrocarbon tails, and the minimum occurs at the concentration where all of the hydration shells are touching each other. Thus, the characteristics of the hydration of the tail that cause the decrease and the features of the water models that reproduce this type of hydration are also examined here. The results show that a single-site multipole water model with a charge distribution that mimics the large quadrupole and the p-orbital type electron density out of the molecular plane has “brittle” hydration with hydrogen bonds that break as the tails touch, which reproduces the deep minimum. However, water models with more typical site representations with partial charges lead to flexible hydration that tends to stay intact, which produces a shallow minimum. Thus, brittle hydration may play an essential role in hydrophobic association in water

Partial molar volume of mefenamic acid in alcohol at temperatures between T=293.15 and T=313.15 K

OpenAIRE

Iqbal, Muhammad J.; Siddiquah, Mahrukh

2006-01-01

Apparent molar volume (Vphi), partial molar volume (V), solute-solute interaction parameter (Sv), partial molar expansivity (E(0)2) and isobaric thermal expansion coefficient (alpha2) of mefenamic acid in six different organic solvents namely, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 2-butanol, have been calculated from the measured solution densities over a temperature range of T=293.15 and T=313.15±0.1K. The solution densities were measured by an automated vibrating tube de...

Multi-tissue partial volume quantification in multi-contrast MRI using an optimised spectral unmixing approach.

Science.gov (United States)

Collewet, Guylaine; Moussaoui, Saïd; Deligny, Cécile; Lucas, Tiphaine; Idier, Jérôme

2018-06-01

Multi-tissue partial volume estimation in MRI images is investigated with a viewpoint related to spectral unmixing as used in hyperspectral imaging. The main contribution of this paper is twofold. It firstly proposes a theoretical analysis of the statistical optimality conditions of the proportion estimation problem, which in the context of multi-contrast MRI data acquisition allows to appropriately set the imaging sequence parameters. Secondly, an efficient proportion quantification algorithm based on the minimisation of a penalised least-square criterion incorporating a regularity constraint on the spatial distribution of the proportions is proposed. Furthermore, the resulting developments are discussed using empirical simulations. The practical usefulness of the spectral unmixing approach for partial volume quantification in MRI is illustrated through an application to food analysis on the proving of a Danish pastry. Copyright © 2018 Elsevier Inc. All rights reserved.

Partial molar volumes of (acetonitrile + water) mixtures over the temperature range (273.15 to 318.15) K

International Nuclear Information System (INIS)

Yeow, Y. Leong; Leong, Yee-Kwong

2007-01-01

Isothermal molar volume data of (acetonitrile + water) mixtures, between T = 273.15 K and T = 318.15 K, extracted from different sources are combined and treated as a single set to even out minor differences between sources and to increase the number of data points for each temperature. Tikhonov regularization is applied to compute the isothermal first and second derivatives of these data with respect to molar composition. For the reference temperature of 298.15 K, this computation is extended to the third derivative. Generalized Cross Validation is used to guide the selection of the regularization parameter that keeps noise amplification under control. The resulting first derivatives are used to construct the partial molar volume curves which are then checked against published results. Properties of the partial molar volumes are analysed by examining their derivatives. Finally the general shape of the second derivative curve of molar volume is explained qualitatively in terms of tripartite segmentation of the molar composition interval but quantitative comparisons are required to confirm this explanation

Densities and volume properties of (water + tert-butanol) over the temperature range of (274.15 to 348.15) K at pressure of 0.1 MPa

International Nuclear Information System (INIS)

Egorov, Gennadiy I.; Makarov, Dmitriy M.

2011-01-01

The densities of {water (1) + tert-butanol (2)} binary mixture were measured over the temperature range (274.15 to 348.15) K at atmospheric pressure using 'Anton Paar' digital vibrating-tube densimeter. Density measurements were carried out over the whole concentration range at (308.15 to 348.15) K. The following volume parameters were calculated: excess molar volumes and thermal isobaric expansivities of the mixture, partial molar volumes and partial molar thermal isobaric expansivities of the components. Concentration dependences of excess molar volumes were fitted with Redlich-Kister equation. The results of partial molar volume calculations using four equations were compared. It was established that for low alcohol concentrations at T ≤ 208 K the inflection points at x 2 ∼ 0.02 were observed at concentration dependences of specific volume. The concentration dependences of partial molar volumes of both water and tert-butanol had extremes at low alcohol content. The temperature dependence of partial molar volumes of water had some inversion at x 2 ∼ 0.65. The temperature dependence of partial molar volumes of tert-butanol at infinite dilution had minimum at ∼288 K. It was discovered that concentration dependences of thermal isobaric expansivities of the mixture at small alcohol content and low temperatures passed through minimum.

Finite volume for three-flavour Partially Quenched Chiral Perturbation Theory through NNLO in the meson sector

Science.gov (United States)

Bijnens, Johan; Rössler, Thomas

2015-11-01

We present a calculation of the finite volume corrections to meson masses and decay constants in three flavour Partially Quenched Chiral Perturbation Theory (PQChPT) through two-loop order in the chiral expansion for the flavour-charged (or off-diagonal) pseudoscalar mesons. The analytical results are obtained for three sea quark flavours with one, two or three different masses. We reproduce the known infinite volume results and the finite volume results in the unquenched case. The calculation has been performed using the supersymmetric formulation of PQChPT as well as with a quark flow technique.

Combining MRI with PET for partial volume correction improves image-derived input functions in mice

Energy Technology Data Exchange (ETDEWEB)

Evans, Eleanor; Buonincontri, Guido [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Izquierdo, David [Athinoula A Martinos Centre, Harvard University, Cambridge, MA (United States); Methner, Carmen [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Hawkes, Rob C [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Ansorge, Richard E [Department of Physics, University of Cambridge, Cambridge (United Kingdom); Kreig, Thomas [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Carpenter, T Adrian [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Sawiak, Stephen J [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge (United Kingdom)

2014-07-29

Kinetic modelling in PET requires the arterial input function (AIF), defined as the time-activity curve (TAC) in plasma. This measure is challenging to obtain in mice due to low blood volumes, resulting in a reliance on image-based methods for AIF derivation. We present a comparison of PET- and MR-based region-of-interest (ROI) analysis to obtain image-derived AIFs from the left ventricle (LV) of a mouse model. ROI-based partial volume correction (PVC) was performed to improve quantification.

Combining MRI with PET for partial volume correction improves image-derived input functions in mice

International Nuclear Information System (INIS)

Evans, Eleanor; Buonincontri, Guido; Izquierdo, David; Methner, Carmen; Hawkes, Rob C; Ansorge, Richard E; Kreig, Thomas; Carpenter, T Adrian; Sawiak, Stephen J

2014-01-01

Kinetic modelling in PET requires the arterial input function (AIF), defined as the time-activity curve (TAC) in plasma. This measure is challenging to obtain in mice due to low blood volumes, resulting in a reliance on image-based methods for AIF derivation. We present a comparison of PET- and MR-based region-of-interest (ROI) analysis to obtain image-derived AIFs from the left ventricle (LV) of a mouse model. ROI-based partial volume correction (PVC) was performed to improve quantification.

The (water + acetonitrile) mixture revisited: A new approach for calculating partial molar volumes

International Nuclear Information System (INIS)

Carmen Grande, Maria del; Julia, Jorge Alvarez; Barrero, Carmen R.; Marschoff, Carlos M.; Bianchi, Hugo L.

2006-01-01

Density and viscosity of (water + acetonitrile) mixtures were measured over the whole composition range at the temperatures: (298.15, 303.15, 308.15, 313.15, and 318.15) K. A new mathematical approach was developed which allows the calculation of the derivatives of density with respect to composition avoiding the appearance of local discontinuities. Thus, reliable partial molar volumes and thermal expansion coefficients were obtained

Target volume delineation in external beam partial breast irradiation: less inter-observer variation with preoperative- compared to postoperative delineation

NARCIS (Netherlands)

Leij, F. van der; Elkhuizen, P.H.M.; Janssen, T.M.; Poortmans, P.M.P.; Sangen, M. van der; Scholten, A.N.; Vliet-Vroegindeweij, C. van; Boersma, L.J.

2014-01-01

The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of

The partial volume effect in the quantification of 1H magnetic resonance spectroscopy in Alzheimer's disease and aging.

Science.gov (United States)

Mato Abad, Virginia; Quirós, Alicia; García-Álvarez, Roberto; Loureiro, Javier Pereira; Alvarez-Linera, Juan; Frank, Ana; Hernández-Tamames, Juan Antonio

2014-01-01

1H-MRS variability increases due to normal aging and also as a result of atrophy in grey and white matter caused by neurodegeneration. In this work, an automatic process was developed to integrate data from spectra and high-resolution anatomical images to quantify metabolites, taking into account tissue partial volumes within the voxel of interest avoiding additional spectra acquisitions required for partial volume correction. To evaluate this method, we use a cohort of 135 subjects (47 male and 88 female, aged between 57 and 99 years) classified into 4 groups: 38 healthy participants, 20 amnesic mild cognitive impairment patients, 22 multi-domain mild cognitive impairment patients, and 55 Alzheimer's disease patients. Our findings suggest that knowing the voxel composition of white and grey matter and cerebrospinal fluid is necessary to avoid partial volume variations in a single-voxel study and to decrease part of the variability found in metabolites quantification, particularly in those studies involving elder patients and neurodegenerative diseases. The proposed method facilitates the use of 1H-MRS techniques in statistical studies in Alzheimer's disease, because it provides more accurate quantitative measurements, reduces the inter-subject variability, and improves statistical results when performing group comparisons.

Brain extraction in partial volumes T2*@7T by using a quasi-anatomic segmentation with bias field correction.

Science.gov (United States)

Valente, João; Vieira, Pedro M; Couto, Carlos; Lima, Carlos S

2018-02-01

Poor brain extraction in Magnetic Resonance Imaging (MRI) has negative consequences in several types of brain post-extraction such as tissue segmentation and related statistical measures or pattern recognition algorithms. Current state of the art algorithms for brain extraction work on weighted T1 and T2, being not adequate for non-whole brain images such as the case of T2*FLASH@7T partial volumes. This paper proposes two new methods that work directly in T2*FLASH@7T partial volumes. The first is an improvement of the semi-automatic threshold-with-morphology approach adapted to incomplete volumes. The second method uses an improved version of a current implementation of the fuzzy c-means algorithm with bias correction for brain segmentation. Under high inhomogeneity conditions the performance of the first method degrades, requiring user intervention which is unacceptable. The second method performed well for all volumes, being entirely automatic. State of the art algorithms for brain extraction are mainly semi-automatic, requiring a correct initialization by the user and knowledge of the software. These methods can't deal with partial volumes and/or need information from atlas which is not available in T2*FLASH@7T. Also, combined volumes suffer from manipulations such as re-sampling which deteriorates significantly voxel intensity structures making segmentation tasks difficult. The proposed method can overcome all these difficulties, reaching good results for brain extraction using only T2*FLASH@7T volumes. The development of this work will lead to an improvement of automatic brain lesions segmentation in T2*FLASH@7T volumes, becoming more important when lesions such as cortical Multiple-Sclerosis need to be detected. Copyright © 2017 Elsevier B.V. All rights reserved.

New finite volume methods for approximating partial differential equations on arbitrary meshes

International Nuclear Information System (INIS)

Hermeline, F.

2008-12-01

This dissertation presents some new methods of finite volume type for approximating partial differential equations on arbitrary meshes. The main idea lies in solving twice the problem to be dealt with. One addresses the elliptic equations with variable (anisotropic, antisymmetric, discontinuous) coefficients, the parabolic linear or non linear equations (heat equation, radiative diffusion, magnetic diffusion with Hall effect), the wave type equations (Maxwell, acoustics), the elasticity and Stokes'equations. Numerous numerical experiments show the good behaviour of this type of method. (author)

Impact of partial-volume correction in oncological PET studies. A systematic review and meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Cysouw, Matthijs C.F.; Kramer, Gerbrand M.; Hoekstra, Otto S. [VU University Medical Centre, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); Schoonmade, Linda J. [VU University Medical Centre, Department of Medical Library, Amsterdam (Netherlands); Boellaard, Ronald [VU University Medical Centre, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); University Medical Centre Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); Vet, Henrica C.W. de [VU University Medical Centre, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands)

2017-11-15

Positron-emission tomography can be useful in oncology for diagnosis, (re)staging, determining prognosis, and response assessment. However, partial-volume effects hamper accurate quantification of lesions <2-3 x the PET system's spatial resolution, and the clinical impact of this is not evident. This systematic review provides an up-to-date overview of studies investigating the impact of partial-volume correction (PVC) in oncological PET studies. We searched in PubMed and Embase databases according to the PRISMA statement, including studies from inception till May 9, 2016. Two reviewers independently screened all abstracts and eligible full-text articles and performed quality assessment according to QUADAS-2 and QUIPS criteria. For a set of similar diagnostic studies, we statistically pooled the results using bivariate meta-regression. Thirty-one studies were eligible for inclusion. Overall, study quality was good. For diagnosis and nodal staging, PVC yielded a strong trend of increased sensitivity at expense of specificity. Meta-analysis of six studies investigating diagnosis of pulmonary nodules (679 lesions) showed no significant change in diagnostic accuracy after PVC (p = 0.222). Prognostication was not improved for non-small cell lung cancer and esophageal cancer, whereas it did improve for head and neck cancer. Response assessment was not improved by PVC for (locally advanced) breast cancer or rectal cancer, and it worsened in metastatic colorectal cancer. The accumulated evidence to date does not support routine application of PVC in standard clinical PET practice. Consensus on the preferred PVC methodology in oncological PET should be reached. Partial-volume-corrected data should be used as adjuncts to, but not yet replacement for, uncorrected data. (orig.)

Adaptive partial volume classification of MRI data

International Nuclear Information System (INIS)

Chiverton, John P; Wells, Kevin

2008-01-01

Tomographic biomedical images are commonly affected by an imaging artefact known as the partial volume (PV) effect. The PV effect produces voxels composed of a mixture of tissues in anatomical magnetic resonance imaging (MRI) data resulting in a continuity of these tissue classes. Anatomical MRI data typically consist of a number of contiguous regions of tissues or even contiguous regions of PV voxels. Furthermore discontinuities exist between the boundaries of these contiguous image regions. The work presented here probabilistically models the PV effect using spatial regularization in the form of continuous Markov random fields (MRFs) to classify anatomical MRI brain data, simulated and real. A unique approach is used to adaptively control the amount of spatial regularization imposed by the MRF. Spatially derived image gradient magnitude is used to identify the discontinuities between image regions of contiguous tissue voxels and PV voxels, imposing variable amounts of regularization determined by simulation. Markov chain Monte Carlo (MCMC) is used to simulate the posterior distribution of the probabilistic image model. Promising quantitative results are presented for PV classification of simulated and real MRI data of the human brain.

Effect of partial volume correction on muscarinic cholinergic receptor imaging with single-photon emission tomography in patients with temporal lobe epilepsy

International Nuclear Information System (INIS)

Weckesser, M.; Ziemons, K.; Griessmeier, M.; Sonnenberg, F.; Langen, K.J.; Mueller-Gaertner, H.W.; Hufnagel, A.; Elger, C.E.; Hacklaender, T.; Holschbach, M.

1997-01-01

Animal experiments and preliminary results in humans have indicated alterations of hippocampal muscarinic acetylcholine receptors (mAChR) in temporal lobe epilepsy. Patients with temporal lobe epilepsy often present with a reduction in hippocampal volume. The aim of this study was to investigate the influence of hippocampal atrophy on the quantification of mAChR with single photon emission tomography (SPET) in patients with temporal lobe epilepsy. Cerebral uptake of the muscarinic cholinergic antagonist [ 123 I]4-iododexetimide (IDex) was investigated by SPET in patients suffering from temporal lobe epilepsy of unilateral (n=6) or predominantly unilateral (n=1) onset. Regions of interest were drawn on co-registered magnetic resonance images. Hippocampal volume was determined in these regions and was used to correct the SPET results for partial volume effects. A ratio of hippocampal IDex binding on the affected side to that on the unaffected side was used to detect changes in muscarinic cholinergic receptor density. Before partial volume correction a decrease in hippocampal IDex binding on the focus side was found in each patient. After partial volume no convincing differences remained. Our results indicate that the reduction in hippocampal IDex binding in patients with epilepsy is due to a decrease in hippocampal volume rather than to a decrease in receptor concentration. (orig.). With 2 figs., 2 tabs

Target volume delineation in external beam partial breast irradiation: Less inter-observer variation with preoperative- compared to postoperative delineation

International Nuclear Information System (INIS)

Leij, Femke van der; Elkhuizen, Paula H.M.; Janssen, Tomas M.; Poortmans, Philip; Sangen, Maurice van der; Scholten, Astrid N.; Vliet-Vroegindeweij, Corine van; Boersma, Liesbeth J.

2014-01-01

The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of twenty-four breast cancer patients

Intrinsic alterations in the partial molar volume on the protein denaturation: surficial Kirkwood-Buff approach.

Science.gov (United States)

Yu, Isseki; Takayanagi, Masayoshi; Nagaoka, Masataka

2009-03-19

The partial molar volume (PMV) of the protein chymotrypsin inhibitor 2 (CI2) was calculated by all-atom MD simulation. Denatured CI2 showed almost the same average PMV value as that of native CI2. This is consistent with the phenomenological question of the protein volume paradox. Furthermore, using the surficial Kirkwood-Buff approach, spatial distributions of PMV were analyzed as a function of the distance from the CI2 surface. The profiles of the new R-dependent PMV indicate that, in denatured CI2, the reduction in the solvent electrostatic interaction volume is canceled out mainly by an increment in thermal volume in the vicinity of its surface. In addition, the PMV of the denatured CI2 was found to increase in the region in which the number density of water atoms is minimum. These results provide a direct and detailed picture of the mechanism of the protein volume paradox suggested by Chalikian et al.

Hydration of alcohol clusters in 1-propanol-water mixture studied by quasielastic neutron scattering and an interpretation of anomalous excess partial molar volume.

Science.gov (United States)

Misawa, M; Inamura, Y; Hosaka, D; Yamamuro, O

2006-08-21

Quasielastic neutron scattering measurements have been made for 1-propanol-water mixtures in a range of alcohol concentration from 0.0 to 0.167 in mole fraction at 25 degrees C. Fraction alpha of water molecules hydrated to fractal surface of alcohol clusters in 1-propanol-water mixture was obtained as a function of alcohol concentration. Average hydration number N(ws) of 1-propanol molecule is derived from the value of alpha as a function of alcohol concentration. By extrapolating N(ws) to infinite dilution, we obtain values of 12-13 as hydration number of isolated 1-propanol molecule. A simple interpretation of structural origin of anomalous excess partial molar volume of water is proposed and as a result a simple equation for the excess partial molar volume is deduced in terms of alpha. Calculated values of the excess partial molar volumes of water and 1-propanol and the excess molar volume of the mixture are in good agreement with experimental values.

Study on optimal fat content in total parenteral nutrition in partially hepatectomized rats.

Science.gov (United States)

Abe, S; Sakabe, S; Hirata, M; Kamuro, H; Asahara, N; Watanabe, M

1997-04-01

In order to investigate the optimal fat content for total parenteral nutrition (TPN) solutions, male Wistar rats were subjected to 70% hepatectomy and then placed, for five days, on one of five TPN regimens in which fat represented 0%, 10%, 20%, 30% and 40%, respectively, of the total calorie content. As serum triglyceride levels in the fat-treated groups were lower than those in the non-treated normal rats, it was concluded that the administered fat was sufficiently hydrolyzed. The greater the fat content, the higher the regeneration rate of the remnant liver. Significant differences were found between the 0%-fat group and 20%-plus fat groups. Hepatic triglyceride level was significantly lower in the 20%-fat group. Hepatic protein level was significantly elevated in all fat-treated groups. Serum phospholipids and total cholesterol due to the lecithin contained in fat emulsion were significantly elevated in the 30 and 40%-fat groups, indicating that fat content of 30 and 40% was excessive. The results suggest that TPN containing fat is superior to fat-free TPN for liver regeneration after partial hepatectomy, and that optimal fat content is estimated to be about 20% of total calorie content in the case of this fat emulsion.

Partial molar volumes of L-alanine, DL-serine, DL-threonine, L-histidine, glycine, and glycylglycine in water, NaCl, and DMSO aqueous solutions at T 298.15 K

International Nuclear Information System (INIS)

Yuan Quan; Li Zhifen; Wang Baohuai

2006-01-01

The apparent molar volumes of L-alanine, DL-serine, DL-threonine, L-histidine, glycine, and glycylglycine in water and in the aqueous solutions of NaCl and DMSO with various concentrations at T = 298.15 K have been measured by the precise vibrating-tube digital densimeter. The calculated partial molar volumes at infinite dilution have been used to obtain corresponding transfer volumes from water to various solutions. The experimental results show that the standard partial molar volumes of the above amino acids and peptide at the dilute DMSO aqueous solutions are very close to those in water. However, the volumes show several types of variations with the increase of the concentrations of DMSO due to different types of side chain of amino acids, which should be discussed specifically. The NaCl changes considerably the infinite dilution standard partial molar volumes of the above amino acids and peptide in the aqueous solutions. The infinite dilution standard partial molar volumes of the each amino acids and peptide increase with the concentrations of NaCl. The experimental results have been rationalized by a cosphere overlap model

Fast Computation of Solvation Free Energies with Molecular Density Functional Theory: Thermodynamic-Ensemble Partial Molar Volume Corrections.

Science.gov (United States)

Sergiievskyi, Volodymyr P; Jeanmairet, Guillaume; Levesque, Maximilien; Borgis, Daniel

2014-06-05

Molecular density functional theory (MDFT) offers an efficient implicit-solvent method to estimate molecule solvation free-energies, whereas conserving a fully molecular representation of the solvent. Even within a second-order approximation for the free-energy functional, the so-called homogeneous reference fluid approximation, we show that the hydration free-energies computed for a data set of 500 organic compounds are of similar quality as those obtained from molecular dynamics free-energy perturbation simulations, with a computer cost reduced by 2-3 orders of magnitude. This requires to introduce the proper partial volume correction to transform the results from the grand canonical to the isobaric-isotherm ensemble that is pertinent to experiments. We show that this correction can be extended to 3D-RISM calculations, giving a sound theoretical justification to empirical partial molar volume corrections that have been proposed recently.

Prognostic value of partial genetic instability in Neuroblastoma with ? 50% neuroblastic cell content.

OpenAIRE

2011-01-01

Abstract Aims. Better understanding of neuroblastoma genetics will improve with genome-wide techniques. However it is not adequated to perform these analyses in samples with less than 60% neuroblastic cell content. We evaluated the utility of FISH on tissue microarrays (TMA) in detecting partial genetic instability (PGI), focussing on samples with ? 50% neuroblastic cells. Methods and results. Alterations of 11q and 17q were detected by FISH on 369 neuroblastic samples included...

Influence of Nanosilica Filler Content in LDPE Composites on Partial Discharge Characteristics

Institute of Scientific and Technical Information of China (English)

Z. Abdul-Malek; A.M. Azzin; Y.Z. Ariel; Aulia; K.Y. Lau; M. Jaafar

2011-01-01

Partial discharges （PDs） due to artificial void in samples of LDPE nanocomposite sheet have been investiga- ted in this work. PDs may cause the degradation of insulating materials and may affect the lifetime of high-voltage ap- paratus. An experimental work using sphere ball-plane electrode system （CIGRE Method II） and a 1.0 mm LDPE composite sheet was carried out. Different weight percentages of nanosilica （0%, 2%, 4%, 6% and 8%） were used. PD experimental results, such as PD magnitude and PD number （both PD pulse polarities）, as functions of the ap- plied stress duration at a specified applied voltage were compared. The surface morphology of specimens was also presented and this conforms to the PD findings. The experimental results show that the PD characteristics of the LDPE generally improve with the introduction of nanosilica, the composite with the highest content of filler, namely the 8% （wt） nanosilica sample has the least partial discharge activities.

Measurement of thyroid volume, iodine concentration and total iodine content by CT and its clinical significance

International Nuclear Information System (INIS)

Nakaji, Shunsuke; Imanishi, Yoshimasa; Okamoto, Kyouko; Shinagawa, Toshihito

2007-01-01

Recently, Imanishi et al have developed new CT software for quantitative in vivo measurement of thyroid iodine. Using a CT system with the software, we measured volume, iodine concentration and total iodine content of thyroids in 63 controls and 435 patients with various diffuse thyroid diseases and thyroid nodules. In controls, all of them showed no difference between the sexes. Although the iodine concentration of the thyroid showed no difference among children, adults and seniles, the volume and total iodine content of the thyroid appeared smaller in children and seniles than in adults. In addition, although the volume and iodine concentration of the thyroid had two peaks in distribution, the total iodine content had almost normal distribution. Normal range of volume, iodine concentration and total iodine content in adults were 5.2-15.5 cm 3 , 0.28831-0.85919 mg/cm 3 and 2.35-11.69 mg, respectively. In thyroid nodule, there is no significant difference in volume, iodine concentration and total iodine content between benign and malignant nodules. All nodules with iodine concentration of less than 0.00007 mg/cm 3 were benign. No thyroid was higher in iodine concentration than the normal range although the thyroid was lower in 78.7% of patients with diffuse thyroid diseases. In all thyroids with increasing iodine concentration and total iodine content in medication course, thyroidal symptoms and signs were uncontrollable by the medication. In 43.8% of patients with long-period systemic diseases, the thyroid showed abnormality in any of the three. We concluded that quantitative in vivo measurement of thyroid iodine by CT could assist the diagnosis of thyroid diseases and decision of therapeutic methods. (author)

Super-resolution reconstruction in frequency, image, and wavelet domains to reduce through-plane partial voluming in MRI

International Nuclear Information System (INIS)

Gholipour, Ali; Afacan, Onur; Scherrer, Benoit; Prabhu, Sanjay P.; Warfield, Simon K.; Aganj, Iman; Sahin, Mustafa

2015-01-01

Purpose: To compare and evaluate the use of super-resolution reconstruction (SRR), in frequency, image, and wavelet domains, to reduce through-plane partial voluming effects in magnetic resonance imaging. Methods: The reconstruction of an isotropic high-resolution image from multiple thick-slice scans has been investigated through techniques in frequency, image, and wavelet domains. Experiments were carried out with thick-slice T2-weighted fast spin echo sequence on the Academic College of Radiology MRI phantom, where the reconstructed images were compared to a reference high-resolution scan using peak signal-to-noise ratio (PSNR), structural similarity image metric (SSIM), mutual information (MI), and the mean absolute error (MAE) of image intensity profiles. The application of super-resolution reconstruction was then examined in retrospective processing of clinical neuroimages of ten pediatric patients with tuberous sclerosis complex (TSC) to reduce through-plane partial voluming for improved 3D delineation and visualization of thin radial bands of white matter abnormalities. Results: Quantitative evaluation results show improvements in all evaluation metrics through super-resolution reconstruction in the frequency, image, and wavelet domains, with the highest values obtained from SRR in the image domain. The metric values for image-domain SRR versus the original axial, coronal, and sagittal images were PSNR = 32.26 vs 32.22, 32.16, 30.65; SSIM = 0.931 vs 0.922, 0.924, 0.918; MI = 0.871 vs 0.842, 0.844, 0.831; and MAE = 5.38 vs 7.34, 7.06, 6.19. All similarity metrics showed high correlations with expert ranking of image resolution with MI showing the highest correlation at 0.943. Qualitative assessment of the neuroimages of ten TSC patients through in-plane and out-of-plane visualization of structures showed the extent of partial voluming effect in a real clinical scenario and its reduction using SRR. Blinded expert evaluation of image resolution in

Super-resolution reconstruction in frequency, image, and wavelet domains to reduce through-plane partial voluming in MRI

Energy Technology Data Exchange (ETDEWEB)

Gholipour, Ali, E-mail: ali.gholipour@childrens.harvard.edu; Afacan, Onur; Scherrer, Benoit; Prabhu, Sanjay P.; Warfield, Simon K. [Department of Radiology, Boston Children’s Hospital, Boston, Massachusetts 02115 and Harvard Medical School, Boston, Massachusetts 02115 (United States); Aganj, Iman [Radiology Department, Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, Massachusetts 02129 and Harvard Medical School, Boston, Massachusetts 02115 (United States); Sahin, Mustafa [Department of Neurology, Boston Children’s Hospital, Boston, Massachusetts 02115 and Harvard Medical School, Boston, Massachusetts 02115 (United States)

2015-12-15

Purpose: To compare and evaluate the use of super-resolution reconstruction (SRR), in frequency, image, and wavelet domains, to reduce through-plane partial voluming effects in magnetic resonance imaging. Methods: The reconstruction of an isotropic high-resolution image from multiple thick-slice scans has been investigated through techniques in frequency, image, and wavelet domains. Experiments were carried out with thick-slice T2-weighted fast spin echo sequence on the Academic College of Radiology MRI phantom, where the reconstructed images were compared to a reference high-resolution scan using peak signal-to-noise ratio (PSNR), structural similarity image metric (SSIM), mutual information (MI), and the mean absolute error (MAE) of image intensity profiles. The application of super-resolution reconstruction was then examined in retrospective processing of clinical neuroimages of ten pediatric patients with tuberous sclerosis complex (TSC) to reduce through-plane partial voluming for improved 3D delineation and visualization of thin radial bands of white matter abnormalities. Results: Quantitative evaluation results show improvements in all evaluation metrics through super-resolution reconstruction in the frequency, image, and wavelet domains, with the highest values obtained from SRR in the image domain. The metric values for image-domain SRR versus the original axial, coronal, and sagittal images were PSNR = 32.26 vs 32.22, 32.16, 30.65; SSIM = 0.931 vs 0.922, 0.924, 0.918; MI = 0.871 vs 0.842, 0.844, 0.831; and MAE = 5.38 vs 7.34, 7.06, 6.19. All similarity metrics showed high correlations with expert ranking of image resolution with MI showing the highest correlation at 0.943. Qualitative assessment of the neuroimages of ten TSC patients through in-plane and out-of-plane visualization of structures showed the extent of partial voluming effect in a real clinical scenario and its reduction using SRR. Blinded expert evaluation of image resolution in

A spreadsheet to determine the volume ratio for target and breast in partial breast irradiation

International Nuclear Information System (INIS)

Kron, T.; Willis, D.; Miller, J.; Hubbard, P.; Oliver, M.; Chua, B.

2009-01-01

Full text: The technical feasibility of Partial Breast Irradiation (PBI) using external beam radiotherapy depends on the ratio between the evaluation planning target volume (PTV e val) and the whole breast volume (PBI volume ratio = PVR). We aimed to develop a simple method to determine PVR using measurements performed at the time of the planning CT scan. A PVR calculation tool was developed using a Microsoft Excel spreadsheet to determine the PTV from three orthogonal dimensions of the seroma cavity and a given margin on the CT scans. The breast volume is estimated from the separation and breast height in five equally spaced CT slices. The PTV e val and whole breast volume were determined for 29 patients from two centres using the spreadsheet calculation tool and compared to volumes delineated on computerised treatment planning systems. Both the PTV e val and whole breast volumes were underestimated by approximately 25% using the spreadsheet. The resulting PVRs were 1.05 +/- 0.35 (mean +/- 1 S D) times larger than the ones determined from planning. Estimations of the PVR using the calculation tool were achievable in around 5 minutes at the time of CT scanning and allow a prompt decision on the suitability of the patients for PBI.

When structure affects function--the need for partial volume effect correction in functional and resting state magnetic resonance imaging studies.

Science.gov (United States)

Dukart, Juergen; Bertolino, Alessandro

2014-01-01

Both functional and also more recently resting state magnetic resonance imaging have become established tools to investigate functional brain networks. Most studies use these tools to compare different populations without controlling for potential differences in underlying brain structure which might affect the functional measurements of interest. Here, we adapt a simulation approach combined with evaluation of real resting state magnetic resonance imaging data to investigate the potential impact of partial volume effects on established functional and resting state magnetic resonance imaging analyses. We demonstrate that differences in the underlying structure lead to a significant increase in detected functional differences in both types of analyses. Largest increases in functional differences are observed for highest signal-to-noise ratios and when signal with the lowest amount of partial volume effects is compared to any other partial volume effect constellation. In real data, structural information explains about 25% of within-subject variance observed in degree centrality--an established resting state connectivity measurement. Controlling this measurement for structural information can substantially alter correlational maps obtained in group analyses. Our results question current approaches of evaluating these measurements in diseased population with known structural changes without controlling for potential differences in these measurements.

An Examination of Exposure Control and Content Balancing Restrictions on Item Selection in CATs Using the Partial Credit Model.

Science.gov (United States)

Davis, Laurie Laughlin; Pastor, Dena A.; Dodd, Barbara G.; Chiang, Claire; Fitzpatrick, Steven J.

2003-01-01

Examined the effectiveness of the Sympson-Hetter technique and rotated content balancing relative to no exposure control and no content rotation conditions in a computerized adaptive testing system based on the partial credit model. Simulation results show the Sympson-Hetter technique can be used with minimal impact on measurement precision,…

VOLUME ESTIMATION, DRY WEIGHT, OIL CONTENT AND QUANTITY OF FENCEPOSTS OF CANDEIA (Eremanthus erythropappus (DC MacLeish

Directory of Open Access Journals (Sweden)

José Roberto Soares Scolforo

2004-06-01

Full Text Available This research aimed at studying the behavior of volume, dry weight, oil content and fence post quantity per diametric class of candeia; to define its stack factor, with and without diametric class control; and to determine equations for estimating the main stem and branches volume, dry weight and oil content of the hole tree, trunk, branches and leaves and fencepost quantity. Data were obtained from a forest inventory carried out in a native candeia forest located in Aiuruoca county, Minas Gerais state - Brazil. Tree volume was calculated through the Huber formula and oil extraction methods employed were “the solvent method” and “vapor hauling method”. For estimation volume, dry weight, oil content and fencepost number the traditional double entry models were used. The oil weight in 1 cubic meter of wood of small dimensions, trees between 5 and 10cm, is around 6 kilos, while the oil content of the largest trees, between 40 and 45cm, is around 11 kilos. The same tendency is observed for the wood volume, without bark, and in the volume of piled up wood, although in these last situations the magnitude of quantities are different. The oil content of candeia trees present the following behavior: in the stem and branches up to 3cm of diameter with bark, it varies from 1,02% to 1,37%, respectively to plants with diameter between 5 and 10cm and between 40 and 45cm; in the branches with less than 3cm of diameter with bark, it varies from 0,33% to 0,65%,respectively, to plants between 5 and 10cm and between 40 and 45cm of diameter; in the leaves it varies from 0,28% to 0,77%, respectively, for plants between 5-10cm and between 40-45cm of diameter. The average stack factor is 1.9087 and diminishes as diameter classes increases. The best model for estimating oil content, dry weight, fence post quantity and volume is the logarithmic form of Schumacher-Hall model.

Estimating the two-particle $K$-matrix for multiple partial waves and decay channels from finite-volume energies

DEFF Research Database (Denmark)

Morningstar, Colin; Bulava, John; Singha, Bijit

2017-01-01

An implementation of estimating the two-to-two $K$-matrix from finite-volume energies based on the L\\"uscher formalism and involving a Hermitian matrix known as the "box matrix" is described. The method includes higher partial waves and multiple decay channels. Two fitting procedures for estimating...

Clinical application of calculated split renal volume using computed tomography-based renal volumetry after partial nephrectomy: Correlation with technetium-99m dimercaptosuccinic acid renal scan data.

Science.gov (United States)

Lee, Chan Ho; Park, Young Joo; Ku, Ja Yoon; Ha, Hong Koo

2017-06-01

To evaluate the clinical application of computed tomography-based measurement of renal cortical volume and split renal volume as a single tool to assess the anatomy and renal function in patients with renal tumors before and after partial nephrectomy, and to compare the findings with technetium-99m dimercaptosuccinic acid renal scan. The data of 51 patients with a unilateral renal tumor managed by partial nephrectomy were retrospectively analyzed. The renal cortical volume of tumor-bearing and contralateral kidneys was measured using ImageJ software. Split estimated glomerular filtration rate and split renal volume calculated using this renal cortical volume were compared with the split renal function measured with technetium-99m dimercaptosuccinic acid renal scan. A strong correlation between split renal function and split renal volume of the tumor-bearing kidney was observed before and after surgery (r = 0.89, P volumetry had a strong correlation with the split renal function measured using technetium-99m dimercaptosuccinic acid renal scan. Computed tomography-based split renal volume measurement before and after partial nephrectomy can be used as a single modality for anatomical and functional assessment of the tumor-bearing kidney. © 2017 The Japanese Urological Association.

Noise suppressed partial volume correction for cardiac SPECT/CT

Energy Technology Data Exchange (ETDEWEB)

Chan, Chung; Liu, Chi, E-mail: chi.liu@yale.edu [Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut 06520 (United States); Liu, Hui [Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut 06520 and Key Laboratory of Particle and Radiation Imaging (Tsinghua University), Ministry of Education, Beijing 100084 (China); Grobshtein, Yariv [GE Healthcare, Haifa 3910101 (Israel); Stacy, Mitchel R. [Department of Internal Medicine, Yale University, New Haven, Connecticut 06520 (United States); Sinusas, Albert J. [Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut 06520 and Department of Internal Medicine, Yale University, New Haven, Connecticut 06520 (United States)

2016-09-15

Purpose: Partial volume correction (PVC) methods typically improve quantification at the expense of increased image noise and reduced reproducibility. In this study, the authors developed a novel voxel-based PVC method that incorporates anatomical knowledge to improve quantification while suppressing noise for cardiac SPECT/CT imaging. Methods: In the proposed method, the SPECT images were first reconstructed using anatomical-based maximum a posteriori (AMAP) with Bowsher’s prior to penalize noise while preserving boundaries. A sequential voxel-by-voxel PVC approach (Yang’s method) was then applied on the AMAP reconstruction using a template response. This template response was obtained by forward projecting a template derived from a contrast-enhanced CT image, and then reconstructed using AMAP to model the partial volume effects (PVEs) introduced by both the system resolution and the smoothing applied during reconstruction. To evaluate the proposed noise suppressed PVC (NS-PVC), the authors first simulated two types of cardiac SPECT studies: a {sup 99m}Tc-tetrofosmin myocardial perfusion scan and a {sup 99m}Tc-labeled red blood cell (RBC) scan on a dedicated cardiac multiple pinhole SPECT/CT at both high and low count levels. The authors then applied the proposed method on a canine equilibrium blood pool study following injection with {sup 99m}Tc-RBCs at different count levels by rebinning the list-mode data into shorter acquisitions. The proposed method was compared to MLEM reconstruction without PVC, two conventional PVC methods, including Yang’s method and multitarget correction (MTC) applied on the MLEM reconstruction, and AMAP reconstruction without PVC. Results: The results showed that the Yang’s method improved quantification, however, yielded increased noise and reduced reproducibility in the regions with higher activity. MTC corrected for PVE on high count data with amplified noise, although yielded the worst performance among all the methods

A New Approach for Deep Gray Matter Analysis Using Partial-Volume Estimation.

Science.gov (United States)

Bonnier, Guillaume; Kober, Tobias; Schluep, Myriam; Du Pasquier, Renaud; Krueger, Gunnar; Meuli, Reto; Granziera, Cristina; Roche, Alexis

2016-01-01

The existence of partial volume effects in brain MR images makes it challenging to understand physio-pathological alterations underlying signal changes due to pathology across groups of healthy subjects and patients. In this study, we implement a new approach to disentangle gray and white matter alterations in the thalamus and the basal ganglia. The proposed method was applied to a cohort of early multiple sclerosis (MS) patients and healthy subjects to evaluate tissue-specific alterations related to diffuse inflammatory or neurodegenerative processes. Forty-three relapsing-remitting MS patients and nineteen healthy controls underwent 3T MRI including: (i) fluid-attenuated inversion recovery, double inversion recovery, magnetization-prepared gradient echo for lesion count, and (ii) T1 relaxometry. We applied a partial volume estimation algorithm to T1 relaxometry maps to gray and white matter local concentrations as well as T1 values characteristic of gray and white matter in the thalamus and the basal ganglia. Statistical tests were performed to compare groups in terms of both global T1 values, tissue characteristic T1 values, and tissue concentrations. Significant increases in global T1 values were observed in the thalamus (p = 0.038) and the putamen (p = 0.026) in RRMS patients compared to HC. In the Thalamus, the T1 increase was associated with a significant increase in gray matter characteristic T1 (p = 0.0016) with no significant effect in white matter. The presented methodology provides additional information to standard MR signal averaging approaches that holds promise to identify the presence and nature of diffuse pathology in neuro-inflammatory and neurodegenerative diseases.

A method for partial volume correction of PET-imaged tumor heterogeneity using expectation maximization with a spatially varying point spread function

International Nuclear Information System (INIS)

Barbee, David L; Holden, James E; Nickles, Robert J; Jeraj, Robert; Flynn, Ryan T

2010-01-01

Tumor heterogeneities observed in positron emission tomography (PET) imaging are frequently compromised by partial volume effects which may affect treatment prognosis, assessment or future implementations such as biologically optimized treatment planning (dose painting). This paper presents a method for partial volume correction of PET-imaged heterogeneous tumors. A point source was scanned on a GE Discovery LS at positions of increasing radii from the scanner's center to obtain the spatially varying point spread function (PSF). PSF images were fit in three dimensions to Gaussian distributions using least squares optimization. Continuous expressions were devised for each Gaussian width as a function of radial distance, allowing for generation of the system PSF at any position in space. A spatially varying partial volume correction (SV-PVC) technique was developed using expectation maximization (EM) and a stopping criterion based on the method's correction matrix generated for each iteration. The SV-PVC was validated using a standard tumor phantom and a tumor heterogeneity phantom and was applied to a heterogeneous patient tumor. SV-PVC results were compared to results obtained from spatially invariant partial volume correction (SINV-PVC), which used directionally uniform three-dimensional kernels. SV-PVC of the standard tumor phantom increased the maximum observed sphere activity by 55 and 40% for 10 and 13 mm diameter spheres, respectively. Tumor heterogeneity phantom results demonstrated that as net changes in the EM correction matrix decreased below 35%, further iterations improved overall quantitative accuracy by less than 1%. SV-PVC of clinically observed tumors frequently exhibited changes of ±30% in regions of heterogeneity. The SV-PVC method implemented spatially varying kernel widths and automatically determined the number of iterations for optimal restoration, parameters which are arbitrarily chosen in SINV-PVC. Comparing SV-PVC to SINV-PVC demonstrated

Partial Molar Volumes of 15-Crown-5 Ether in Mixtures of N,N-Dimethylformamide with Water.

Science.gov (United States)

Tyczyńska, Magdalena; Jóźwiak, Małgorzata

2014-01-01

The density of 15-crown-5 ether (15C5) solutions in the mixtures of N,N -dimethylformamide (DMF) and water (H 2 O) was measured within the temperature range 293.15-308.15 K using an Anton Paar oscillatory U-tube densimeter. The results were used to calculate the apparent molar volumes ( V Φ ) of 15C5 in the mixtures of DMF + H 2 O over the whole concentration range. Using the apparent molar volumes and Redlich and Mayer equation, the standard partial molar volumes of 15-crown-5 were calculated at infinite dilution ([Formula: see text]). The limiting apparent molar expansibilities ( α ) were also calculated. The data are discussed from the point of view of the effect of concentration changes on interactions in solution.

Partial Molar Volumes of Air-Component Gases in Several Liquid n-Alkanes and 1-Alkanols at 313.15 K

Czech Academy of Sciences Publication Activity Database

Izák, Pavel; Cibulka, I.; Heintz, A.

1995-01-01

Roč. 109, č. 2 (1995), s. 227-234 ISSN 0378-3812 Keywords : data density * partial molar volume * gas -liquid mixture Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.024, year: 1995

High insoluble fibre content increases in vitro starch digestibility in partially baked breads.

Science.gov (United States)

Ronda, Felicidad; Rivero, Pablo; Caballero, Pedro A; Quilez, Joan

2012-12-01

Wheat breads prepared from frozen partially baked breads were characterized by their content of rapidly digestible starch (RDS) and slowly digestible starch (SDS) by the in vitro starch digestibility method developed by Englyst. Breads with different contents and types of fibre and breads prepared with different fermentation processes were studied. Bread with inulin and with a double fermentation had the lowest RDS content of 58.8 ± 1.7 and 60.0 ± 1.9 (% dry matter), respectively. Wheat bran bread, seeded bread, triple fermentation white bread and baguette-type bread showed values of RDS between 63.1 ± 1.7 and 65.7 ± 1.7 with no significant differences between them (p breads than in breads with added fibre. The highest values of the starch digestive rate index (SDRI) were obtained by the three types of breads with added fibre, which ranged from 91.8 ± 3.5 to 95.8 ± 3.5 versus 80.2 ± 3.5 to 87.5 ± 3.5 for white wheat breads. A significant (p bread crumbs corroborated this statement.

The Multivariate Regression Statistics Strategy to Investigate Content-Effect Correlation of Multiple Components in Traditional Chinese Medicine Based on a Partial Least Squares Method.

Science.gov (United States)

Peng, Ying; Li, Su-Ning; Pei, Xuexue; Hao, Kun

2018-03-01

Amultivariate regression statisticstrategy was developed to clarify multi-components content-effect correlation ofpanaxginseng saponins extract and predict the pharmacological effect by components content. In example 1, firstly, we compared pharmacological effects between panax ginseng saponins extract and individual saponin combinations. Secondly, we examined the anti-platelet aggregation effect in seven different saponin combinations of ginsenoside Rb1, Rg1, Rh, Rd, Ra3 and notoginsenoside R1. Finally, the correlation between anti-platelet aggregation and the content of multiple components was analyzed by a partial least squares algorithm. In example 2, firstly, 18 common peaks were identified in ten different batches of panax ginseng saponins extracts from different origins. Then, we investigated the anti-myocardial ischemia reperfusion injury effects of the ten different panax ginseng saponins extracts. Finally, the correlation between the fingerprints and the cardioprotective effects was analyzed by a partial least squares algorithm. Both in example 1 and 2, the relationship between the components content and pharmacological effect was modeled well by the partial least squares regression equations. Importantly, the predicted effect curve was close to the observed data of dot marked on the partial least squares regression model. This study has given evidences that themulti-component content is a promising information for predicting the pharmacological effects of traditional Chinese medicine.

SCC with high volume of fly ash content

Directory of Open Access Journals (Sweden)

Bakhrakh Anton

2017-01-01

Full Text Available Self-compacting concrete is a very perspective building material. It provides great benefits during the construction of heavily reinforced buildings. SCC has outstanding properties such as high flowability, dense structure and high strength due to specific quality of aggregates, fillers, their proportion in mix, use of polycarboxylate-based superplasticizers. Main disadvantages of SCC are high price and the difficulty of obtaining a proper mix. Use of fillers, such as fly ash type F, is a way to make SCC cheaper by replacing part of cement. Fly ash also provides some technological and operating advantages. In this paper the influence of high volume (60% from cement fly ash type F on the properties of concrete mixture and hardened concrete is investigated. The result of the work shows the possibility of reduction the cost of SCC using ordinary fillers and high amount of fly ash. The investigated SCC has low speed of hardening (7-day compressive strength at the range of 41.8 MPa and high volume of entrained air content (3.5%.

PETPVC: a toolbox for performing partial volume correction techniques in positron emission tomography

Science.gov (United States)

Thomas, Benjamin A.; Cuplov, Vesna; Bousse, Alexandre; Mendes, Adriana; Thielemans, Kris; Hutton, Brian F.; Erlandsson, Kjell

2016-11-01

Positron emission tomography (PET) images are degraded by a phenomenon known as the partial volume effect (PVE). Approaches have been developed to reduce PVEs, typically through the utilisation of structural information provided by other imaging modalities such as MRI or CT. These methods, known as partial volume correction (PVC) techniques, reduce PVEs by compensating for the effects of the scanner resolution, thereby improving the quantitative accuracy. The PETPVC toolbox described in this paper comprises a suite of methods, both classic and more recent approaches, for the purposes of applying PVC to PET data. Eight core PVC techniques are available. These core methods can be combined to create a total of 22 different PVC techniques. Simulated brain PET data are used to demonstrate the utility of toolbox in idealised conditions, the effects of applying PVC with mismatched point-spread function (PSF) estimates and the potential of novel hybrid PVC methods to improve the quantification of lesions. All anatomy-based PVC techniques achieve complete recovery of the PET signal in cortical grey matter (GM) when performed in idealised conditions. Applying deconvolution-based approaches results in incomplete recovery due to premature termination of the iterative process. PVC techniques are sensitive to PSF mismatch, causing a bias of up to 16.7% in GM recovery when over-estimating the PSF by 3 mm. The recovery of both GM and a simulated lesion was improved by combining two PVC techniques together. The PETPVC toolbox has been written in C++, supports Windows, Mac and Linux operating systems, is open-source and publicly available.

Towards a Video Passive Content Fingerprinting Method for Partial-Copy Detection Robust against Non-Simulated Attacks.

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Zobeida Jezabel Guzman-Zavaleta

Full Text Available Passive content fingerprinting is widely used for video content identification and monitoring. However, many challenges remain unsolved especially for partial-copies detection. The main challenge is to find the right balance between the computational cost of fingerprint extraction and fingerprint dimension, without compromising detection performance against various attacks (robustness. Fast video detection performance is desirable in several modern applications, for instance, in those where video detection involves the use of large video databases or in applications requiring real-time video detection of partial copies, a process whose difficulty increases when videos suffer severe transformations. In this context, conventional fingerprinting methods are not fully suitable to cope with the attacks and transformations mentioned before, either because the robustness of these methods is not enough or because their execution time is very high, where the time bottleneck is commonly found in the fingerprint extraction and matching operations. Motivated by these issues, in this work we propose a content fingerprinting method based on the extraction of a set of independent binary global and local fingerprints. Although these features are robust against common video transformations, their combination is more discriminant against severe video transformations such as signal processing attacks, geometric transformations and temporal and spatial desynchronization. Additionally, we use an efficient multilevel filtering system accelerating the processes of fingerprint extraction and matching. This multilevel filtering system helps to rapidly identify potential similar video copies upon which the fingerprint process is carried out only, thus saving computational time. We tested with datasets of real copied videos, and the results show how our method outperforms state-of-the-art methods regarding detection scores. Furthermore, the granularity of our method makes

Lowering the alcohol content of red wine does not alter its cardioprotective properties

OpenAIRE

Lamont, Kim; Blackhurst, Dee; Albertyn, Zulfah; Marais, David; Lecour, Sandrine

2012-01-01

BACKGROUND: Many epidemiological, clinical and laboratory studies suggest that chronic and moderate consumption of red wine benefits cardiovascular health, because of the alcoholic content or the polyphenols/flavonoids. Aims. The antioxidant and cardioprotective properties of a French red wine (cabernet sauvignon, 12% alcohol by volume) were compared with those of the same wine subjected to reverse osmosis for partial removal of alcohol (6% alcohol by volume). METHODS: Antioxidant capacity wa...

An improved approach to reduce partial volume errors in brain SPET

International Nuclear Information System (INIS)

Hatton, R.L.; Hatton, B.F.; Michael, G.; Barnden, L.; QUT, Brisbane, QLD; The Queen Elizabeth Hospital, Adelaide, SA

1999-01-01

Full text: Limitations in SPET resolution give rise to significant partial volume error (PVE) in small brain structures We have investigated a previously published method (Muller-Gartner et al., J Cereb Blood Flow Metab 1992;16: 650-658) to correct PVE in grey matter using MRI. An MRI is registered and segmented to obtain a grey matter tissue volume which is then smoothed to obtain resolution matched to the corresponding SPET. By dividing the original SPET with this correction map, structures can be corrected for PVE on a pixel-by-pixel basis. Since this approach is limited by space-invariant filtering, modification was made by estimating projections for the segmented MRI and reconstructing these using identical parameters to SPET. The methods were tested on simulated brain scans, reconstructed with the ordered subsets EM algorithm (8,16, 32, 64 equivalent EM iterations) The new method provided better recovery visually. For 32 EM iterations, recovery coefficients were calculated for grey matter regions. The effects of potential errors in the method were examined. Mean recovery was unchanged with one pixel registration error, the maximum error found in most registration programs. Errors in segmentation > 2 pixels results in loss of accuracy for small structures. The method promises to be useful for reducing PVE in brain SPET

The Multivariate Regression Statistics Strategy to Investigate Content-Effect Correlation of Multiple Components in Traditional Chinese Medicine Based on a Partial Least Squares Method

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Ying Peng

2018-03-01

Full Text Available Amultivariate regression statisticstrategy was developed to clarify multi-components content-effect correlation ofpanaxginseng saponins extract and predict the pharmacological effect by components content. In example 1, firstly, we compared pharmacological effects between panax ginseng saponins extract and individual saponin combinations. Secondly, we examined the anti-platelet aggregation effect in seven different saponin combinations of ginsenoside Rb1, Rg1, Rh, Rd, Ra3 and notoginsenoside R1. Finally, the correlation between anti-platelet aggregation and the content of multiple components was analyzed by a partial least squares algorithm. In example 2, firstly, 18 common peaks were identified in ten different batches of panax ginseng saponins extracts from different origins. Then, we investigated the anti-myocardial ischemia reperfusion injury effects of the ten different panax ginseng saponins extracts. Finally, the correlation between the fingerprints and the cardioprotective effects was analyzed by a partial least squares algorithm. Both in example 1 and 2, the relationship between the components content and pharmacological effect was modeled well by the partial least squares regression equations. Importantly, the predicted effect curve was close to the observed data of dot marked on the partial least squares regression model. This study has given evidences that themulti-component content is a promising information for predicting the pharmacological effects of traditional Chinese medicine.

Towards a universal method for calculating hydration free energies: a 3D reference interaction site model with partial molar volume correction

International Nuclear Information System (INIS)

Palmer, David S; Frolov, Andrey I; Ratkova, Ekaterina L; Fedorov, Maxim V

2010-01-01

We report a simple universal method to systematically improve the accuracy of hydration free energies calculated using an integral equation theory of molecular liquids, the 3D reference interaction site model. A strong linear correlation is observed between the difference of the experimental and (uncorrected) calculated hydration free energies and the calculated partial molar volume for a data set of 185 neutral organic molecules from different chemical classes. By using the partial molar volume as a linear empirical correction to the calculated hydration free energy, we obtain predictions of hydration free energies in excellent agreement with experiment (R = 0.94, σ = 0.99 kcal mol -1 for a test set of 120 organic molecules). (fast track communication)

Towards a universal method for calculating hydration free energies: a 3D reference interaction site model with partial molar volume correction.

Science.gov (United States)

Palmer, David S; Frolov, Andrey I; Ratkova, Ekaterina L; Fedorov, Maxim V

2010-12-15

We report a simple universal method to systematically improve the accuracy of hydration free energies calculated using an integral equation theory of molecular liquids, the 3D reference interaction site model. A strong linear correlation is observed between the difference of the experimental and (uncorrected) calculated hydration free energies and the calculated partial molar volume for a data set of 185 neutral organic molecules from different chemical classes. By using the partial molar volume as a linear empirical correction to the calculated hydration free energy, we obtain predictions of hydration free energies in excellent agreement with experiment (R = 0.94, σ = 0.99 kcal mol (- 1) for a test set of 120 organic molecules).

Target volume definition for external beam partial breast radiotherapy: Clinical, pathological and technical studies informing current approaches

International Nuclear Information System (INIS)

Kirby, Anna M.; Coles, Charlotte E.; Yarnold, John R.

2010-01-01

Partial breast irradiation (PBI) is currently under investigation in several phase III trials and, following a recent consensus statement, its use off-study may increase despite ongoing uncertainty regarding optimal target volume definition. We review the clinical, pathological and technical evidence for target volume definition in external beam partial breast irradiation (EB-PBI). The optimal method of tumour bed (TB) delineation requires X-ray CT imaging of implanted excision cavity wall markers. The definition of clinical target volume (CTV) as TB plus concentric 15 mm margins is based on the anatomical distribution of multifocal and multicentric disease around the primary tumour in mastectomy specimens, and the clinical locations of local tumour relapse (LR) after breast conservation surgery. If the majority of LR originate from foci of residual invasive and/or intraduct disease in the vicinity of the TB after complete microscopic resection, CTV margin logically takes account of the position of primary tumour within the surgical resection specimen. The uncertain significance of independent primary tumours as sources of preventable LR, and of wound healing responses in stimulating LR, increases the difficulties in defining optimal CTV. These uncertainties may resolve after long-term follow-up of current PBI trials. By contrast, a commonly used 10 mm clinical to planning target volume (PTV) margin has a stronger evidence base, although departmental set-up errors need to be confirmed locally. A CTV-PTV margin >10 mm may be required in women with larger breasts and/or large seromas, whilst the role of image-guided radiotherapy with or without TB markers in reducing CTV-PTV margins needs to be explored.

Volume I. Environmental effects on contents of Cs-137 and Sr-90 in milk. Volume II. Appendices

International Nuclear Information System (INIS)

1981-01-01

Milk, animal fodders, soils, humans, livestock, and wildlife on or near 55 dairy farms in Utah were assayed for radionuclide content. Effects of soil chemistry, water supply, plant type, farming practices, geographic location, altitude, rainfall, and other ecological differences were sought by intensive analysis. Although many analyses have not been completed, several cause-effect relationships have been defined. Wet-lands yield more 137 Cs, 131 I, or 90 Sr to milk under like conditions of fallout intensity than dry-lands. In most cases, the station with the highest yield is also practicing wet grazing. 90 Sr and 137 Cs content of milk is enhanced by sandy soils. Increased altitude and higher rainfall lead to higher yields of 90 Sr and 137 Cs in milk. Levels of 137 Cs in milk increase from south to north, and Utah can be divided into several regions, each having a characteristic level of 90 Sr and 137 Cs in milk, meat, and fodders. Poor pastures (over-grazed to the extent that stem bases are eaten and much soil is exposed) yield more 137 Cs and 90 Sr than improved pastures. Feeding green chop alfalfa or putting the animals on the meadows causes marked but temporary increases in the 90 Sr and 137 Cs content of the milk. However, the annual yield for two stations of similar ecology in the same geographic area is essentially the same. Experimental details are presented in Volume I. The appendices in Volume II are made up primarily of the data compiled at the 78 stations

Partial molar volumes and viscosities of aqueous hippuric acid solutions containing LiCl and MnCl2 · 4H2O at 303.15 K

Science.gov (United States)

Deosarkar, S. D.; Tawde, P. D.; Zinjade, A. B.; Shaikh, A. I.

2015-09-01

Density (ρ) and viscosity (η) of aqueous hippuric acid (HA) solutions containing LiCl and MnCl2 · 4H2O have been studied at 303.15 K in order to understand volumetric and viscometric behavior of these systems. Apparent molar volume (φv) of salts were calculated from density data and fitted to Massons relation and partial molar volumes (φ{v/0}) at infinite dilution were determined. Relative viscosity data has been used to determine viscosity A and B coefficients using Jones-Dole relation. Partial molar volume and viscosity coefficients have been discussed in terms of ion-solvent interactions and overall structural fittings in solution.

Water-vapor pressure control in a volume

Science.gov (United States)

Scialdone, J. J.

1978-01-01

The variation with time of the partial pressure of water in a volume that has openings to the outside environment and includes vapor sources was evaluated as a function of the purging flow and its vapor content. Experimental tests to estimate the diffusion of ambient humidity through openings and to validate calculated results were included. The purging flows required to produce and maintain a certain humidity in shipping containers, storage rooms, and clean rooms can be estimated with the relationship developed here. These purging flows are necessary to prevent the contamination, degradation, and other effects of water vapor on the systems inside these volumes.

Estimating the two-particle K-matrix for multiple partial waves and decay channels from finite-volume energies

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Colin Morningstar

2017-11-01

Full Text Available An implementation of estimating the two-to-two K-matrix from finite-volume energies based on the Lüscher formalism and involving a Hermitian matrix known as the “box matrix” is described. The method includes higher partial waves and multiple decay channels. Two fitting procedures for estimating the K-matrix parameters, which properly incorporate all statistical covariances, are discussed. Formulas and software for handling total spins up to S=2 and orbital angular momenta up to L=6 are obtained for total momenta in several directions. First tests involving ρ-meson decay to two pions include the L=3 and L=5 partial waves, and the contributions from these higher waves are found to be negligible in the elastic energy range.

Quadrupole terms in the Maxwell equations: Born energy, partial molar volume, and entropy of ions.

Science.gov (United States)

Slavchov, Radomir I; Ivanov, Tzanko I

2014-02-21

A new equation of state relating the macroscopic quadrupole moment density Q to the gradient of the field ∇E in an isotropic fluid is derived: Q = αQ(∇E - U∇·E/3), where the quadrupolarizability αQ is proportional to the squared molecular quadrupole moment. Using this equation of state, a generalized expression for the Born energy of an ion dissolved in quadrupolar solvent is obtained. It turns out that the potential and the energy of a point charge in a quadrupolar medium are finite. From the obtained Born energy, the partial molar volume and the partial molar entropy of a dissolved ion follow. Both are compared to experimental data for a large number of simple ions in aqueous solutions. From the comparison the value of the quadrupolar length LQ is determined, LQ = (αQ/3ɛ)(1/2) = 1-4 Å. Data for ion transfer from aqueous to polar oil solution are analyzed, which allowed for the determination of the quadrupolarizability of nitrobenzene.

Concentration dependence of the partial volume, viscosity, and electric conductivity of solutions of lithium salts in aliphatic alcohols

International Nuclear Information System (INIS)

Eliseeva, O.V.; Golubev, V.V.

2003-01-01

Concentration dependence of partial volumes, electric conductivity and viscosity of lithium nitrate and chloride solutions in methanol, propanol, isopropanol, butanol, isobutanol, pentanol and isopentanol at 298.15 K were studied by the methods of densimetry, conductometry and viscosimetry. Structural specific features of the solutions studied are discussed on the basis of the calculated volumetric characteristics of the substance dissolved and solvent [ru

Gastric volume rather than nutrient content inhibits food intake.

Science.gov (United States)

Phillips, R J; Powley, T L

1996-09-01

To evaluate the separate contributions of distension and nutrient stimulation of the stomach to the inhibition of short-term food intake and, particularly, to reassess previous analyses based on the inflatable gastrointestinal cuff, four experiments were performed. Rats equipped with pyloric cuffs and indwelling gastric catheters consumed a liquid diet ad libitum. Their consumption during short-term (30 min) feeding bout was measured after gastric infusions on cuff-open and cuff-closed trials. Animals taking meals (approximately 5 ml) with cuffs closed immediately after receiving intragastric infusions of 2.5, 5, 7.5, or 10 ml of normal saline exhibited both suppression at the smallest infusion and a dose-dependent reduction across the other volumes (experiment 1). Additionally, when the test diet concentration was varied, animals with their cuffs closed consumed a constant volume, not a constant number of calories (experiment 2). Furthermore, cuff-closed animals exhibited no more suppression to 5-ml intragastric infusions of nutrients (including, on different trials, 50 and 100% Isocal diet; 10, 20, and 40% glucose; and 40% sucrose and 40% fructose) than to the same volume of saline (experiments 3 and 4). In contrast, on cuff-open trials in which gastric contents could empty into the duodenum, these same nutrient loads were more effective (except fructose) than saline in producing suppression of food intake. In summary, although both limited gastric distension with the pylorus occluded and intestinal nutrient stimulation with the cuff open effectively reduced intake, cuff-closed gastric loads of mixed macronutrients or carbohydrate solutions of 2-8 kcal, pH from 5.8 to 6.7, and osmolarities between 117 and 2,294 mosM/kg produced only the distension-based suppression generated by the same volume of saline.

Feasibility and performance of novel software to quantify metabolically active volumes and 3D partial volume corrected SUV and metabolic volumetric products of spinal bone marrow metastases on 18F-FDG-PET/CT.

Science.gov (United States)

Torigian, Drew A; Lopez, Rosa Fernandez; Alapati, Sridevi; Bodapati, Geetha; Hofheinz, Frank; van den Hoff, Joerg; Saboury, Babak; Alavi, Abass

2011-01-01

Our aim was to assess feasibility and performance of novel semi-automated image analysis software called ROVER to quantify metabolically active volume (MAV), maximum standardized uptake value-maximum (SUV(max)), 3D partial volume corrected mean SUV (cSUV(mean)), and 3D partial volume corrected mean MVP (cMVP(mean)) of spinal bone marrow metastases on fluorine-18 fluorodeoxyglucose-positron emission tomography/computerized tomography ((18)F-FDG-PET/CT). We retrospectively studied 16 subjects with 31 spinal metastases on FDG-PET/CT and MRI. Manual and ROVER determinations of lesional MAV and SUV(max), and repeated ROVER measurements of MAV, SUV(max), cSUV(mean) and cMVP(mean) were made. Bland-Altman and correlation analyses were performed to assess reproducibility and agreement. Our results showed that analyses of repeated ROVER measurements revealed MAV mean difference (D)=-0.03±0.53cc (95% CI(-0.22, 0.16)), lower limit of agreement (LLOA)=-1.07cc, and upper limit of agreement (ULOA)=1.01cc; SUV(max) D=0.00±0.00 with LOAs=0.00; cSUV(mean) D=-0.01±0.39 (95% CI(-0.15, 0.13)), LLOA=-0.76, and ULOA=0.75; cMVP(mean) D=-0.52±4.78cc (95% CI(-2.23, 1.23)), LLOA=-9.89cc, and ULOA=8.86cc. Comparisons between ROVER and manual measurements revealed volume D= -0.39±1.37cc (95% CI (-0.89, 0.11)), LLOA=-3.08cc, and ULOA=2.30cc; SUV(max) D=0.00±0.00 with LOAs=0.00. Mean percent increase in lesional SUV(mean) and MVP(mean) following partial volume correction using ROVER was 84.25±36.00% and 84.45±35.94% , respectively. In conclusion, it is feasible to estimate MAV, SUV(max), cSUV(mean), and cMVP(mean) of spinal bone marrow metastases from (18)F-FDG-PET/CT quickly and easily with good reproducibility via ROVER software. Partial volume correction is imperative, as uncorrected SUV(mean) and MVP(mean) are significantly underestimated, even for large lesions. This novel approach has great potential for practical, accurate, and precise combined structural-functional PET

The Partial Molar Volume and Thermal Expansivity of Fe2O3 in Alkali Silicate Liquids: Evidence for the Average Coordination of Fe3+

Science.gov (United States)

Liu, Q.; Lange, R.

2003-12-01

was obtained in a fit to a linear volume equation in which the other oxide components have the following fitted partial molar volumes (cm3/mol) at 1100° C: SiO2 = 26.85+/-0.04, Na2O = 26.57+/-0.07, K2O = 42.34+/-0.10, and FeO = 12.84+/-0.28, and the following fitted fitted partial molar thermal expansivities (10-3 cm3/mol-K): Na2O = 7.73+/-0.12, K2O = 11.99+/-0.24, and FeO = 2.88+/-1.22. For the three sodic liquids not included in this regression, the most iron-rich (18.2 mol% Fe2O3) has a value for VFe2O3 of 44.1 cm3/mole, whereas the most iron-poor (4.4 mol% Fe2O3) has a value for VFe2O3 of 37.0 cm3/mole. This trend may reflect a greater proportion of four-fold ferric iron in iron-rich liquids, which mirrors the trend of increasing ferric-ferrous ratios in sodic liquids as a function of total iron content (Lange and Carmichael, 1989). The most polymerized liquid in our data set was a sodic liquid that has a value for VFe2O3 of 45.0 cm3/mole. It thus appears that most (13 of 16) of our experimental liquids, which span a wide compositional range, lead to a VFe2O3 (41.6 cm3/mol) which is constant with composition and temperature. However, there are three important outliers that may have implications for the appropriate value to apply to magmatic liquids.

Isotropic non-white matter partial volume effects in constrained spherical deconvolution

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Timo eRoine

2014-03-01

Full Text Available Diffusion-weighted (DW magnetic resonance imaging (MRI is a noninvasive imaging method, which can be used to investigate neural tracts in the white matter (WM of the brain. Significant partial volume effects (PVE are present in the DW signal due to relatively large voxel sizes. These PVEs can be caused by both non-WM tissue, such as gray matter (GM and cerebrospinal fluid (CSF, and by multiple nonparallel WM fiber populations. High angular resolution diffusion imaging (HARDI methods have been developed to correctly characterize complex WM fiber configurations, but to date, many of the HARDI methods do not account for non-WM PVEs. In this work, we investigated the isotropic PVEs caused by non-WM tissue in WM voxels on fiber orientations extracted with constrained spherical deconvolution (CSD. Experiments were performed on simulated and real DW-MRI data. In particular, simulations were performed to demonstrate the effects of varying the diffusion weightings, signal-to-noise ratios (SNR, fiber configurations, and tissue fractions.Our results show that the presence of non-WM tissue signal causes a decrease in the precision of the detected fiber orientations and an increase in the detection of false peaks in CSD. We estimated 35-50 % of WM voxels to be affected by non-WM PVEs. For HARDI sequences, which typically have a relatively high degree of diffusion weighting, these adverse effects are most pronounced in voxels with GM PVEs. The non-WM PVEs become severe with 50 % GM volume for maximum spherical harmonics orders of 8 and below, and already with 25 % GM volume for higher orders. In addition, a low diffusion weighting or SNR increases the effects. The non-WM PVEs may cause problems in connectomics, where reliable fiber tracking at the WM-GM interface is especially important. We suggest acquiring data with high diffusion-weighting 2500-3000 s/mm2, reasonable SNR (~30 and using lower SH orders in GM contaminated regions to minimize the non-WM PVEs

Isotropic non-white matter partial volume effects in constrained spherical deconvolution.

Science.gov (United States)

Roine, Timo; Jeurissen, Ben; Perrone, Daniele; Aelterman, Jan; Leemans, Alexander; Philips, Wilfried; Sijbers, Jan

2014-01-01

Diffusion-weighted (DW) magnetic resonance imaging (MRI) is a non-invasive imaging method, which can be used to investigate neural tracts in the white matter (WM) of the brain. Significant partial volume effects (PVEs) are present in the DW signal due to relatively large voxel sizes. These PVEs can be caused by both non-WM tissue, such as gray matter (GM) and cerebrospinal fluid (CSF), and by multiple non-parallel WM fiber populations. High angular resolution diffusion imaging (HARDI) methods have been developed to correctly characterize complex WM fiber configurations, but to date, many of the HARDI methods do not account for non-WM PVEs. In this work, we investigated the isotropic PVEs caused by non-WM tissue in WM voxels on fiber orientations extracted with constrained spherical deconvolution (CSD). Experiments were performed on simulated and real DW-MRI data. In particular, simulations were performed to demonstrate the effects of varying the diffusion weightings, signal-to-noise ratios (SNRs), fiber configurations, and tissue fractions. Our results show that the presence of non-WM tissue signal causes a decrease in the precision of the detected fiber orientations and an increase in the detection of false peaks in CSD. We estimated 35-50% of WM voxels to be affected by non-WM PVEs. For HARDI sequences, which typically have a relatively high degree of diffusion weighting, these adverse effects are most pronounced in voxels with GM PVEs. The non-WM PVEs become severe with 50% GM volume for maximum spherical harmonics orders of 8 and below, and already with 25% GM volume for higher orders. In addition, a low diffusion weighting or SNR increases the effects. The non-WM PVEs may cause problems in connectomics, where reliable fiber tracking at the WM-GM interface is especially important. We suggest acquiring data with high diffusion-weighting 2500-3000 s/mm(2), reasonable SNR (~30) and using lower SH orders in GM contaminated regions to minimize the non-WM PVEs in CSD.

Minimization of the volume and Pu content of the waste generated at a plutonium fuel fabrication plant

International Nuclear Information System (INIS)

Pauwels, H.

1992-01-01

The amounts of waste generated during 1987, 1989 and a past reference period have been reported in great detail. The main conclusions which can be drawn from these figures are: (i) for all kinds of waste, the waste-to-product ratio has decreased very substantially during the past few years. This reduction results partly from a scale effect, i.e. the better load factor of the plant, and partly from Belgonucleare's continuous effort to minimize the radioactive waste arisings; (ii) the ratio of the Pu content of the waste to the total Pu throughput of the plant has also decreased substantially; (iii) the mean Pu content of the solid Pu contaminated waste equals 1.39 g Pu per unit volume of 25 l. Only for a small fraction of this waste (<5% by volume) does the Pu content exceed 5 g per unit volume of 25 l; (iv) even after the implementation of waste reducing measures, some 45% of the solid Pu contaminated waste is generated by operations which involve the handling and transfer of powders. Finally, some 63% of the total amount of Pu in the waste can be imputed to these operations

Partial molar volume and isentropic compressibility of symmetrical and asymmetrical quaternary ammonium bromides in aqueous solution

International Nuclear Information System (INIS)

Moreno, Nicolás; Buchner, Richard; Vargas, Edgar F.

2015-01-01

Highlights: • Structural effects of the cations on surrounding water molecules are discussed. • Alkyl-chain geometry determines the hydration of Bu 4 N + isomers. • The “compactness” in the hydration shells varies significantly among the isomers. - Abstract: Values of apparent molar volume and isentropic compressibility of symmetric and asymmetric isomers of tetrabutylammonium bromide, namely tetra-n-butylammonium bromide, tetra-iso-butylammonium bromide, tetra-sec-butylammonium bromide, di-n-butyl-di-iso-butylammonium bromide and di-n-butyl-di-sec-butylammonium bromide, in aqueous solution were determined from density and speed of sound measurements. These properties were obtained as a function of molal concentration within the range of 0.01 < m/mol · kg −1 < 0.1 covering temperatures from 278.15 ⩽ T/K ⩽ 293.15. The partial molar volumes and the apparent isentropic molar compressibility at infinite dilution were calculated and their dependence on temperature examined. The results show that cations with sec-butyl chains have larger structural volumes compared to those with iso-butyl chains. In addition, cations with sec-butyl chains induce smaller structural changes in their hydration shell than the others

Thermodynamic study of (heptane + amine) mixtures. III: Excess and partial molar volumes in mixtures with secondary, tertiary, and cyclic amines at 298.15 K

International Nuclear Information System (INIS)

Lepori, Luciano; Gianni, Paolo; Spanedda, Andrea; Matteoli, Enrico

2011-01-01

Graphical abstract: Highlights: → Excess volumes of (sec., tert., or cyclic amines + heptane) mixtures. → Excess volumes are positive for small size amines and decrease as the size increases. → Group contributions to predict the partial molar volumes of amines in heptane. → The void volume is larger for sec. and tert. than for linear amines in heptane. → The void volume is much smaller for cyclic than for linear amines in heptane. - Abstract: Excess molar volumes V E at 298.15 K were determined by means of a vibrating tube densimeter for binary mixtures of {heptane + open chain secondary (diethyl to dibutyl) and tertiary (triethyl to tripentyl) amines} as well as for cyclic imines (C 2 , C 3 , C 4 , C 6 , and C 7 ) and primary cycloalkylamines (C 5 , C 6 , C 7 , and C 12 ). The V E values were found positive for mixtures involving small size amines, with V E decreasing as the size increases. Negative V E 's were found for tributyl- and tripentylamine, heptamethylenimine, and cyclododecylamine. Mixtures of heptane with cycloheptylamine showed an s-shaped curve. Partial molar volumes V 0 of amines at infinite dilution in heptane were obtained from V E and compared with V 0 of hydrocarbons and other classes of organic compounds taken from literature. An additivity scheme, based on the intrinsic volume approach, was applied to estimate group (CH 3 , CH 2 , CH, C, NH 2 , NH, N, OH, O, CO, and COO) contributions to V 0 . These contributions, the effect of cyclization on V 0 , and the limiting slope of the apparent excess molar volumes were discussed in terms of solute-solvent and solute-solute interactions.

Interobserver variations of target volume delineation and its impact on irradiated volume in accelerated partial breast irradiation with intraoperative interstitial breast implant

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Ritu Raj Upreti

2017-02-01

Full Text Available Purpose: To investigate the interobserver variations in delineation of lumpectomy cavity (LC and clinical target volume (CTV, and its impact on irradiated volume in accelerated partial breast irradiation using intraoperative multicatheter brachytherapy. Material and methods : Delineation of LC and CTV was done by five radiation oncologists on planning computed tomography (CT scans of 20 patients with intraoperative interstitial breast implant. Cavity visualization index (CVI, four-point index ranging from (0 = poor to (3 = excellent was created and assigned by observers for each patient. In total, 200 contours for all observers and 100 treatment plans were evaluated. Spatial concordance (conformity index, CI common , and CIgen, average shift in the center of mass (COM, and ratio of maximum and minimum volumes (V max /V min of LC and CTV were quantified among all observers and statistically analyzed. Variation in active dwell positions (0.5 cm step for each catheter, total reference air kerma (TRAK, volume enclosed by prescription isodose (V100% among observers and its spatial concordance were analyzed. Results : The mean ± SD CI common of LC and CTV was 0.54 ± 0.09, and 0.58 ± 0.08, respectively. Conformity index tends to increase, shift in COM and V max /V min decrease significantly (p < 0.05, as CVI increased. Out of total 309 catheters, 29.8% catheters had no change, 29.8% and 17.5% catheters had variations of 1 and 2 dwell positions (0.5 cm and 1 cm, respectively. 9.3% catheters shown variations ≥ 10 dwell positions (5 cm. The mean ± SD CI common of V100% was 0.75 ± 0.11. The mean observed V max /V min of prescription isodose and TRAK was 1.18 (range, 1.03 to 1.56 and 1.11 (range, 1.03 to 1.35, respectively. Conclusions : Interobserver variability in delineation of target volume was found to be significantly related to CVI. Smaller variability was observed with excellent visualization of LC. Interobserver variations showed dosimetric

Quantification of Arabinose content and batter volume in elite black gram mutants induced by gamma rays and electron beam

International Nuclear Information System (INIS)

Vanniarajan, C.; Sri Subalakhshmi, V.K.I.; Se Shamyugtha; Rajeswaran, G.; Monica, R.; Veni, K.

2017-01-01

Black gram (Vignamungo (L) Hepper) is one among the mostly preferred sources of protein, especially in vegetarian diet. One of the most notable biochemical attributes of black gram is Arabinose. As it plays a vital role in the yeast metabolism, it has a direct correlation with the battering quality of Black gram. MDU 1 variety has the highest Arabinose content of 7.5 per cent and VBN(Bg)4yields higher. Both the varieties have indeterminate growth habit. Hence, these two varieties were chosen and treated with Gamma rays and Electron beam of 100–500 Gy and 200–600 Gy respectively. Twenty desirable mutants were selected in M6 generation based on determinate growth habit and high yield with short duration. These mutants were tested for the Arabinose content along with MDU 1 and VBN (Bg)4, using Bial (1902) method. The results of the selected M6 generation mutants revealed that only three mutants excelled in Arabinose content than MDU 1. Two mutants were found to retain the same Arabinose content as that of MDU 1.Three mutants containing higher Arabinose content, one with lower Arabinose content and the parents were further analysed for batter quantity. The unveiled fact is that the increase in Arabinose content increases the batter volume to a certain extent (Arabinose = 10 %). Eventually, with a due course of increase in Arabinose content, the batter volume decreases. The results were tested for significance and were found to be significant. In this present investigation, it was found that the optimum Arabinose content is 10 per cent, which showed an increased batter volume. It has to be further confirmed by using advanced biochemical and molecular methods. (author)

Quantifying [{sup 18}F]fluorodeoxyglucose uptake in the arterial wall: the effects of dual time-point imaging and partial volume effect correction

Energy Technology Data Exchange (ETDEWEB)

Blomberg, Bjoern A. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark); Bashyam, Arjun; Ramachandran, Abhinay; Gholami, Saeid; Houshmand, Sina; Salavati, Ali; Werner, Tom; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva (Switzerland); University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands)

2015-08-15

The human arterial wall is smaller than the spatial resolution of current positron emission tomographs. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake. We evaluated the impact of a novel method for partial volume effect (PVE) correction with contrast-enhanced CT (CECT) assistance on quantification of arterial wall {sup 18}F-FDG uptake at different imaging time-points. Ten subjects were assessed by CECT imaging and dual time-point PET/CT imaging at approximately 60 and 180 min after {sup 18}F-FDG administration. For both time-points, uptake of {sup 18}F-FDG was determined in the aortic wall by calculating the blood pool-corrected maximum standardized uptake value (cSUV{sub MAX}) and cSUV{sub MEAN}. The PVE-corrected SUV{sub MEAN} (pvcSUV{sub MEAN}) was also calculated using {sup 18}F-FDG PET/CT and CECT images. Finally, corresponding target-to-background ratios (TBR) were calculated. At 60 min, pvcSUV{sub MEAN} was on average 3.1 times greater than cSUV{sub MAX} (P <.0001) and 8.5 times greater than cSUV{sub MEAN} (P <.0001). At 180 min, pvcSUV{sub MEAN} was on average 2.6 times greater than cSUV{sub MAX} (P <.0001) and 6.6 times greater than cSUV{sub MEAN} (P <.0001). This study demonstrated that CECT-assisted PVE correction significantly influences quantification of arterial wall {sup 18}F-FDG uptake. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake with PET. (orig.)

Partial volume effect correction in nuclear medicine: assessment with a mathematical phantom

International Nuclear Information System (INIS)

Silva, Murilo Collete da; Pozzo, Lorena

2009-01-01

Objective: assessment of Van Cittert partial volume effect correction method in nuclear medicine images, with a mathematical phantom. Material and method: we simulated an image of four circular sources of different diameters and intensity of 255 per pixel. The iterative algorithm was applied with 20 iterations and α = 1. We obtained the maximum and average counts on the entire image and in regions of interest placed on each of the sources. We also extracted count profiles plotted along the diameter of each of the sources. Results: the local convergence depends on the size of the source studied: the smaller the source, the greater the number of iterations required. It also depends on the information extracted: the use of average counts provides more homogeneous results than the maximum count. There is a significant improvement in image contrast. Conclusion: this study showed the possibility of qualitative and quantitative improvement in applying the bidimensional iterative Van Cittert method to images of simple geometry. (author)

Reductions in Corpus Callosum Volume Partially Mediate Effects of Prenatal Alcohol Exposure on IQ

Directory of Open Access Journals (Sweden)

Stevie C. Biffen

2018-01-01

Full Text Available Disproportionate volume reductions in the basal ganglia, corpus callosum (CC and hippocampus have been reported in children with prenatal alcohol exposure (PAE. However, few studies have investigated these reductions in high prevalence communities, such as the Western Cape Province of South Africa, and only one study made use of manual tracing, the gold standard of volumetric analysis. The present study examined the effects of PAE on subcortical neuroanatomy using manual tracing and the relation of volumetric reductions in these regions to IQ and performance on the California Verbal Learning Test-Children's Version (CVLT-C, a list learning task sensitive to PAE. High-resolution T1-weighted images were acquired, using a sequence optimized for morphometric neuroanatomical analysis, on a Siemens 3T Allegra MRI scanner from 71 right-handed, 9- to 11-year-old children [9 fetal alcohol syndrome (FAS, 19 partial FAS (PFAS, 24 non-syndromal heavily exposed (HE and 19 non-exposed controls]. Frequency of maternal drinking was ascertained prospectively during pregnancy using timeline follow-back interviews. PAE was examined in relation to volumes of the CC and left and right caudate nuclei, nucleus accumbens and hippocampi. All structures were manually traced using Multitracer. Higher levels of PAE were associated with reductions in CC volume after adjustment for TIV. Although the effect of PAE on CC was confounded with smoking and lead exposure, additional analyses showed that it was not accounted for by these exposures. Amongst dysmorphic children, smaller CC was associated with poorer IQ and CVLT-C scores and statistically mediated the effect of PAE on IQ. In addition, higher levels of PAE were associated with bilateral volume reductions in caudate nuclei and hippocampi, effects that remained significant after control for TIV, child sex and age, socioeconomic status, maternal smoking during pregnancy, and childhood lead exposure. These data confirm

Method to Estimate the Dissolved Air Content in Hydraulic Fluid

Science.gov (United States)

Hauser, Daniel M.

2011-01-01

In order to verify the air content in hydraulic fluid, an instrument was needed to measure the dissolved air content before the fluid was loaded into the system. The instrument also needed to measure the dissolved air content in situ and in real time during the de-aeration process. The current methods used to measure the dissolved air content require the fluid to be drawn from the hydraulic system, and additional offline laboratory processing time is involved. During laboratory processing, there is a potential for contamination to occur, especially when subsaturated fluid is to be analyzed. A new method measures the amount of dissolved air in hydraulic fluid through the use of a dissolved oxygen meter. The device measures the dissolved air content through an in situ, real-time process that requires no additional offline laboratory processing time. The method utilizes an instrument that measures the partial pressure of oxygen in the hydraulic fluid. By using a standardized calculation procedure that relates the oxygen partial pressure to the volume of dissolved air in solution, the dissolved air content is estimated. The technique employs luminescent quenching technology to determine the partial pressure of oxygen in the hydraulic fluid. An estimated Henry s law coefficient for oxygen and nitrogen in hydraulic fluid is calculated using a standard method to estimate the solubility of gases in lubricants. The amount of dissolved oxygen in the hydraulic fluid is estimated using the Henry s solubility coefficient and the measured partial pressure of oxygen in solution. The amount of dissolved nitrogen that is in solution is estimated by assuming that the ratio of dissolved nitrogen to dissolved oxygen is equal to the ratio of the gas solubility of nitrogen to oxygen at atmospheric pressure and temperature. The technique was performed at atmospheric pressure and room temperature. The technique could be theoretically carried out at higher pressures and elevated

Partial Volume Effects correction in emission tomography

International Nuclear Information System (INIS)

Le Pogam, Adrien

2010-01-01

Partial Volume Effects (PVE) designates the blur commonly found in nuclear medicine images and this PhD work is dedicated to their correction with the objectives of qualitative and quantitative improvement of such images. PVE arise from the limited spatial resolution of functional imaging with either Positron Emission Tomography (PET) or Single Photon Emission Computed Tomography (SPECT). They can be defined as a signal loss in tissues of size similar to the Full Width at Half Maximum (FWHM) of the PSF of the imaging device. In addition, PVE induce activity cross contamination between adjacent structures with different tracer uptakes. This can lead to under or over estimation of the real activity of such analyzed regions. Various methodologies currently exist to compensate or even correct for PVE and they may be classified depending on their place in the processing chain: either before, during or after the image reconstruction process, as well as their dependency on co-registered anatomical images with higher spatial resolution, for instance Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). The voxel-based and post-reconstruction approach was chosen for this work to avoid regions of interest definition and dependency on proprietary reconstruction developed by each manufacturer, in order to improve the PVE correction. Two different contributions were carried out in this work: the first one is based on a multi-resolution methodology in the wavelet domain using the higher resolution details of a co-registered anatomical image associated to the functional dataset to correct. The second one is the improvement of iterative deconvolution based methodologies by using tools such as directional wavelets and curvelets extensions. These various developed approaches were applied and validated using synthetic, simulated and clinical images, for instance with neurology and oncology applications in mind. Finally, as currently available PET/CT scanners incorporate more

Effects of replacement of binder content on bond strength of mortars

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E. B. C. Costa

Full Text Available The reduction of binder content in cementitious systems is an effective way to mitigate environmental impacts without increasing costs. The main purpose of this study is to evaluate the effect of content binder on bond strength of mortar-brick interface. For thus, it was studied mortars produced with two limestone fines with different particle size distribution. The limestone fines were added at rates of 0% to 60% at increments of 15% as partial volume replacement of binder. Mortars were prepared in proportion of 1:3 (binder + limestone: sand in volume. The water content was kept constant and equal to 18% in relation to total weight of solids. The mechanical property of mortars was evaluated by tensile strength and the performance of interface by bond strength tests at 14 days. Results indicate that is possible make mortars with 45% less than binder without reducing bond strength. Thus, the use of appropriate particles of limestone can produce more environmentally friendly concrete and rendering mortars by reducing its binder factor without affecting its performance.

Partial twisting for scalar mesons

International Nuclear Information System (INIS)

Agadjanov, Dimitri; Meißner, Ulf-G.; Rusetsky, Akaki

2014-01-01

The possibility of imposing partially twisted boundary conditions is investigated for the scalar sector of lattice QCD. According to the commonly shared belief, the presence of quark-antiquark annihilation diagrams in the intermediate state generally hinders the use of the partial twisting. Using effective field theory techniques in a finite volume, and studying the scalar sector of QCD with total isospin I=1, we however demonstrate that partial twisting can still be performed, despite the fact that annihilation diagrams are present. The reason for this are delicate cancellations, which emerge due to the graded symmetry in partially quenched QCD with valence, sea and ghost quarks. The modified Lüscher equation in case of partial twisting is given

Evaluation of the reconstruction method and effect of partial volume in brain scintiscanning

International Nuclear Information System (INIS)

Pinheiro, Monica Araujo

2016-01-01

Alzheimer's disease is a neurodegenerative disorder, on which occurs a progressive and irreversible destruction of neurons. According to the World Health Organization (WHO) 35.6 million people are living with dementia, being recommended that governments prioritize early diagnosis techniques. Laboratory and psychological tests for cognitive assessment are conducted and further complemented by neurological imaging from nuclear medicine exams in order to establish an accurate diagnosis. The image quality evaluation and reconstruction process effects are important tools in clinical routine. In the present work, these quality parameters were studied, and the effects of partial volume (PVE) for lesions of different sizes and geometries that are attributed to the limited resolution of the equipment. In dementia diagnosis, this effect can be confused with intake losses due to cerebral cortex atrophy. The evaluation was conducted by two phantoms of different shapes as suggested by (a) American College of Radiology (ACR) and (b) National Electrical Manufacturers Association (NEMA) for Contrast, Contrast-to-Noise Ratio (CNR) and Recovery Coefficient (RC) calculation versus lesions shape and size. Technetium-99m radionuclide was used in a local brain scintigraphy protocol, for proportions lesion to background of 2:1, 4:1, 6:1, 8:1 and 10:1. Fourteen reconstruction methods were used for each concentration applying different filters and algorithms. Before the analysis of all image properties, the conclusion is that the predominant effect is the partial volume, leading to errors of measurement of more than 80%. Furthermore, it was demonstrate that the most effective method of reconstruction is FBP with Metz filter, providing better contrast and contrast to noise ratio results. In addition, this method shows the best Recovery Coefficients correction for each lesion. The ACR phantom showed the best results assigned to a more precise reconstruction of a cylinder, which does not

Turbulent piloted partially-premixed flames with varying levels of O2/N2: stability limits and PDF calculations

Science.gov (United States)

Juddoo, Mrinal; Masri, Assaad R.; Pope, Stephen B.

2011-12-01

This paper reports measured stability limits and PDF calculations of piloted, turbulent flames of compressed natural gas (CNG) partially-premixed with either pure oxygen, or with varying levels of O2/N2. Stability limits are presented for flames of CNG fuel premixed with up to 20% oxygen as well as CNG-O2-N2 fuel where the O2 content is varied from 8 to 22% by volume. Calculations are presented for (i) Sydney flame B [Masri et al. 1988] which uses pure CNG as well as flames B15 to B25 where the CNG is partially-premixed with 15-25% oxygen by volume, respectively and (ii) Sandia methane-air (1:3 by volume) flame E [Barlow et al. 2005] as well as new flames E15 and E25 that are partially-premixed with 'reconstituted air' where the O2 content in nitrogen is 15 and 25% by volume, respectively. The calculations solve a transported PDF of composition using a particle-based Monte Carlo method and employ the EMST mixing model as well as detailed chemical kinetics. The addition of oxygen to the fuel increases stability, shortens the flames, broadens the reaction zone, and shifts the stoichiometric mixture fraction towards the inner side of the jet. It is found that for pure CNG flames where the reaction zone is narrow (∼0.1 in mixture fraction space), the PDF calculations fail to reproduce the correct level of local extinction on approach to blow-off. A broadening in the reaction zone up to about 0.25 in mixture fraction space is needed for the PDF/EMST approach to be able to capture these finite-rate chemistry effects. It is also found that for the same level of partial premixing, increasing the O2/N2 ratio increases the maximum levels of CO and NO but shifts the peak to richer mixture fractions. Over the range of oxygenation investigated here, stability limits have shown to improve almost linearly with increasing oxygen levels in the fuel and with increasing the contribution of release rate from the pilot.

Cerebral blood flow in temporal lobe epilepsy: a partial volume correction study

International Nuclear Information System (INIS)

Giovacchini, Giampiero; Bonwetsch, Robert; Theodore, William H.; Herscovitch, Peter; Carson, Richard E.

2007-01-01

Previous studies in temporal lobe epilepsy (TLE) have shown that, owing to brain atrophy, positron emission tomography (PET) can overestimate deficits in measures of cerebral function such as glucose metabolism (CMR glu ) and neuroreceptor binding. The magnitude of this effect on cerebral blood flow (CBF) is unexplored. The aim of this study was to assess CBF deficits in TLE before and after magnetic resonance imaging-based partial volume correction (PVC). Absolute values of CBF for 21 TLE patients and nine controls were computed before and after PVC. In TLE patients, quantitative CMR glu measurements also were obtained. Before PVC, regional values of CBF were significantly (p glu in middle and inferior temporal cortex, fusiform gyrus and hippocampus both before and after PVC. A significant positive relationship between disease duration and AIs for CMR glu , but not CBF, was detected in hippocampus and amygdala, before but not after PVC. PVC should be used for PET CBF measurements in patients with TLE. Reduced blood flow, in contrast to glucose metabolism, is mainly due to structural changes. (orig.)

Correction for Partial Volume Effect Is a Must, Not a Luxury, to Fully Exploit the Potential of Quantitative PET Imaging in Clinical Oncology

DEFF Research Database (Denmark)

Alavi, Abass; Werner, Thomas J; Høilund-Carlsen, Poul Flemming

2018-01-01

The partial volume effect (PVE) is considered as one of the major degrading factors impacting image quality and hampering the accuracy of quantitative PET imaging in clinical oncology. This effect is the consequence of the limited spatial resolution of whole-body PET scanners, which results in bl...

Optimized statistical parametric mapping for partial-volume-corrected amyloid positron emission tomography in patients with Alzheimer's disease and Lewy body dementia

Science.gov (United States)

Oh, Jungsu S.; Kim, Jae Seung; Chae, Sun Young; Oh, Minyoung; Oh, Seung Jun; Cha, Seung Nam; Chang, Ho-Jong; Lee, Chong Sik; Lee, Jae Hong

2017-03-01

We present an optimized voxelwise statistical parametric mapping (SPM) of partial-volume (PV)-corrected positron emission tomography (PET) of 11C Pittsburgh Compound B (PiB), incorporating the anatomical precision of magnetic resonance image (MRI) and amyloid β (A β) burden-specificity of PiB PET. First, we applied region-based partial-volume correction (PVC), termed the geometric transfer matrix (GTM) method, to PiB PET, creating MRI-based lobar parcels filled with mean PiB uptakes. Then, we conducted a voxelwise PVC by multiplying the original PET by the ratio of a GTM-based PV-corrected PET to a 6-mm-smoothed PV-corrected PET. Finally, we conducted spatial normalizations of the PV-corrected PETs onto the study-specific template. As such, we increased the accuracy of the SPM normalization and the tissue specificity of SPM results. Moreover, lobar smoothing (instead of whole-brain smoothing) was applied to increase the signal-to-noise ratio in the image without degrading the tissue specificity. Thereby, we could optimize a voxelwise group comparison between subjects with high and normal A β burdens (from 10 patients with Alzheimer's disease, 30 patients with Lewy body dementia, and 9 normal controls). Our SPM framework outperformed than the conventional one in terms of the accuracy of the spatial normalization (85% of maximum likelihood tissue classification volume) and the tissue specificity (larger gray matter, and smaller cerebrospinal fluid volume fraction from the SPM results). Our SPM framework optimized the SPM of a PV-corrected A β PET in terms of anatomical precision, normalization accuracy, and tissue specificity, resulting in better detection and localization of A β burdens in patients with Alzheimer's disease and Lewy body dementia.

Generalized solutions of nonlinear partial differential equations

CERN Document Server

Rosinger, EE

1987-01-01

During the last few years, several fairly systematic nonlinear theories of generalized solutions of rather arbitrary nonlinear partial differential equations have emerged. The aim of this volume is to offer the reader a sufficiently detailed introduction to two of these recent nonlinear theories which have so far contributed most to the study of generalized solutions of nonlinear partial differential equations, bringing the reader to the level of ongoing research.The essence of the two nonlinear theories presented in this volume is the observation that much of the mathematics concernin

Evaluation of the partial volume effect in the activity quantification in PET/CT images; Avaliacao do efeito de volume parcial na quantificacao de atividade em imagens de PET/CT

Energy Technology Data Exchange (ETDEWEB)

Krempser, Alexandre R., E-mail: krempser@peb.ufrj.br [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Instituto Alberto Luiz Coimbra. Programa de Engenharia Biomedica; Oliveira, Silvia M. Velasques de [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Almeida, Sergio A. de [Hospital Samaritano, Rio de Janeiro, RJ (Brazil). Centro de Imagens PET/CT

2012-08-15

The aim of this work was to evaluate the influence of partial volume effect (PVE) in the quantification of activity in images of a PET-CT scanner and its ability to identify lesions. Recovery coefficients were calculated using a phantom containing 12 cylinders with diameters between 4 and 30 mm and a National Electrical Manufactures Association scattering phantom, both fillable with known concentrations of {sup 18}F. The images were acquired for acquisition time of 3 and 5 minutes, and cylinder to background ratio of n=8:1 and n=4:1. The recovery coefficients were calculated between 0.01 and 0.91 depending on the diameter. Significant variations were not found in function of image acquisition parameters. Errors in the activity quantification above 70% were found for cylinders with diameters smaller than 10 mm. The cylinders with diameters smaller than 8 mm were not identified in the images. The phantoms were adequate for PVE evaluation in the PET/CT images. The PVE had the greatest impact on the cylinders with diameters of 6 and 4 mm. It's necessary to use partial volume correction techniques in the images in order to increase the quantitative accuracy of the studied equipment. (author)

Thermodynamic properties of peptide solutions 20. Partial molar volumes and isothermal compressions for some tripeptides of sequence gly-X-gly (X = gly, ala, leu, asn, thr, and tyr) in aqueous solution at T = 298.15 K and p = (10–120) MPa

International Nuclear Information System (INIS)

Hedwig, Gavin R.; Høiland, Harald

2016-01-01

Highlights: • Sound speeds were measured for aqueous solutions of some tripeptides at high pressures. • Partial molar volumes and isothermal compressions were derived for T = 298.15 K and p = (10–120) MPa. • The partial molar volumes for non-polar amino acid side-chains decrease with increasing pressure. • The partial molar volumes for polar side-chains do not change significantly with increasing pressure. - Abstract: Sound speeds have been measured for aqueous solutions of six tripeptides of sequence glycyl-X-glycine, where X is one of the amino acids glycine, alanine, leucine, asparagine, threonine, and tyrosine at T = 298.15 K and at the pressures p = (10, 20, 40, 60, 80, 100, and 120) MPa. Using methods described in previous work, these sound speeds were used to derive the partial molar volumes at infinite dilution, V_2"o, the partial molar isentropic compressions at infinite dilution, K_S_,_2"o, and the partial molar isothermal compressions at infinite dilution, K"o_T_,_2 {K"o_T_,_2 = −(∂V_2"o/∂p)_T}, for the tripeptides in aqueous solution at the elevated pressures. The results were used to calculate the partial molar volumes and partial molar isothermal compressions for the various amino acid side-chains over the pressure range p = (10–120) MPa.

A simple algorithm for subregional striatal uptake analysis with partial volume correction in dopaminergic PET imaging

International Nuclear Information System (INIS)

Lue Kunhan; Lin Hsinhon; Chuang Kehshih; Kao Chihhao, K.; Hsieh Hungjen; Liu Shuhsin

2014-01-01

In positron emission tomography (PET) of the dopaminergic system, quantitative measurements of nigrostriatal dopamine function are useful for differential diagnosis. A subregional analysis of striatal uptake enables the diagnostic performance to be more powerful. However, the partial volume effect (PVE) induces an underestimation of the true radioactivity concentration in small structures. This work proposes a simple algorithm for subregional analysis of striatal uptake with partial volume correction (PVC) in dopaminergic PET imaging. The PVC algorithm analyzes the separate striatal subregions and takes into account the PVE based on the recovery coefficient (RC). The RC is defined as the ratio of the PVE-uncorrected to PVE-corrected radioactivity concentration, and is derived from a combination of the traditional volume of interest (VOI) analysis and the large VOI technique. The clinical studies, comprising 11 patients with Parkinson's disease (PD) and 6 healthy subjects, were used to assess the impact of PVC on the quantitative measurements. Simulations on a numerical phantom that mimicked realistic healthy and neurodegenerative situations were used to evaluate the performance of the proposed PVC algorithm. In both the clinical and the simulation studies, the striatal-to-occipital ratio (SOR) values for the entire striatum and its subregions were calculated with and without PVC. In the clinical studies, the SOR values in each structure (caudate, anterior putamen, posterior putamen, putamen, and striatum) were significantly higher by using PVC in contrast to those without. Among the PD patients, the SOR values in each structure and quantitative disease severity ratings were shown to be significantly related only when PVC was used. For the simulation studies, the average absolute percentage error of the SOR estimates before and after PVC were 22.74% and 1.54% in the healthy situation, respectively; those in the neurodegenerative situation were 20.69% and 2

Partial volume effect (PVE) on the arterial input function (AIF) in T1-weighted perfusion imaging and limitations of the multiplicative rescaling approach

DEFF Research Database (Denmark)

Hansen, Adam Espe; Pedersen, Henrik; Rostrup, Egill

2009-01-01

The partial volume effect (PVE) on the arterial input function (AIF) remains a major obstacle to absolute quantification of cerebral blood flow (CBF) using MRI. This study evaluates the validity and performance of a commonly used multiplicative rescaling of the AIF to correct for the PVE. In a gr...

Influence of Nitrogen Partial Pressure on Microstructure and Tribological Properties of Mo-Cu-V-N Composite Coatings with High Cu Content

Directory of Open Access Journals (Sweden)

Haijuan Mei

2018-01-01

Full Text Available In this study, Mo-Cu-V-N composite coatings with high Cu content of ~18 at.% were deposited on 316L stainless steel and YT14 cemented carbide substrates by high power impulse magnetron sputtering in Ar–N2 gas mixtures. The influence of N2 partial pressure was investigated with respect to the microstructure and tribological properties of the coatings. The results indicated that the Mo-Cu-V-N composite coatings exhibited FCC B1-MoN phase with a strong (200 preferred orientation, and Cu phase was found to exist as metallic species. As the N2 partial pressure increased from 0.11 to 0.35 Pa, the peak intensity of (200 plane decreased gradually and simultaneous peak broadening was observed, which was typical for grain refinement. With increasing the N2 partial pressure, the columnar microstructure became much coarser, which led to the decrease of residual stress and hardness. The Mo-Cu-V-N composite coatings with high Cu content exhibited a relatively low wear rate of 10−8 mm3/N·m at 25 °C, which was believed to be attributed to the mixed lubricious oxides of MoO2, CuO and V2O5 formed during tribo-oxidation, which cannot be formed in the coatings with low Cu content. When the wear temperature was increased up to 400 °C, the wear rate increased sharply up to 10−6 mm3/N·m despite the formation of lubricious oxides of MoO3/CuMoO4 and V2O5. This could be due to the loss of nitrogen and pronounced oxidation at high temperatures, which led the wear mechanism to be transformed from mild oxidation wear to severe oxidation wear.

Isolation and partial characterization of mutants with elevated lipid content in Chlorella sorokiniana and Scenedesmus obliquus.

Science.gov (United States)

Vigeolas, Hélène; Duby, Francéline; Kaymak, Esra; Niessen, Guillaume; Motte, Patrick; Franck, Fabrice; Remacle, Claire

2012-11-30

This paper describes the isolation and partial biomass characterization of high triacylglycerol (TAG) mutants of Chlorella sorokiniana and Scenedesmus obliquus, two algal species considered as potential source of biodiesel. Following UV mutagenesis, 2000 Chlorella and 2800 Scenedesmus colonies were screened with a method based on Nile Red fluorescence. Several mutants with high Nile Red fluorescence were selected by this high-throughput method in both species. Growth and biomass parameters of the strongest mutants were analyzed in detail. All of the four Chlorella mutants showed no significant changes in growth rate, cell weight, cell size, protein and chlorophyll contents on a per cell basis. Whereas all contained elevated total lipid and TAG content per unit of dry weight, two of them were also affected for starch metabolism, suggesting a change in biomass/storage carbohydrate composition. Two Scenedesmus mutants showed a 1.5 and 2-fold increased cell weight and larger cells compared to the wild type, which led to a general increase of biomass including total lipid and TAG content on a per cell basis. Such mutants could subsequently be used as commercial oleaginous algae and serve as an alternative to conventional petrol. Copyright © 2012 Elsevier B.V. All rights reserved.

Estimation of active pharmaceutical ingredients content using locally weighted partial least squares and statistical wavelength selection.

Science.gov (United States)

Kim, Sanghong; Kano, Manabu; Nakagawa, Hiroshi; Hasebe, Shinji

2011-12-15

Development of quality estimation models using near infrared spectroscopy (NIRS) and multivariate analysis has been accelerated as a process analytical technology (PAT) tool in the pharmaceutical industry. Although linear regression methods such as partial least squares (PLS) are widely used, they cannot always achieve high estimation accuracy because physical and chemical properties of a measuring object have a complex effect on NIR spectra. In this research, locally weighted PLS (LW-PLS) which utilizes a newly defined similarity between samples is proposed to estimate active pharmaceutical ingredient (API) content in granules for tableting. In addition, a statistical wavelength selection method which quantifies the effect of API content and other factors on NIR spectra is proposed. LW-PLS and the proposed wavelength selection method were applied to real process data provided by Daiichi Sankyo Co., Ltd., and the estimation accuracy was improved by 38.6% in root mean square error of prediction (RMSEP) compared to the conventional PLS using wavelengths selected on the basis of variable importance on the projection (VIP). The results clearly show that the proposed calibration modeling technique is useful for API content estimation and is superior to the conventional one. Copyright © 2011 Elsevier B.V. All rights reserved.

Relating oxygen partial pressure, saturation and content: the haemoglobin-oxygen dissociation curve.

Science.gov (United States)

Collins, Julie-Ann; Rudenski, Aram; Gibson, John; Howard, Luke; O'Driscoll, Ronan

2015-09-01

The delivery of oxygen by arterial blood to the tissues of the body has a number of critical determinants including blood oxygen concentration (content), saturation (S O2 ) and partial pressure, haemoglobin concentration and cardiac output, including its distribution. The haemoglobin-oxygen dissociation curve, a graphical representation of the relationship between oxygen satur-ation and oxygen partial pressure helps us to understand some of the principles underpinning this process. Historically this curve was derived from very limited data based on blood samples from small numbers of healthy subjects which were manipulated in vitro and ultimately determined by equations such as those described by Severinghaus in 1979. In a study of 3524 clinical specimens, we found that this equation estimated the S O2 in blood from patients with normal pH and S O2 >70% with remarkable accuracy and, to our knowledge, this is the first large-scale validation of this equation using clinical samples. Oxygen saturation by pulse oximetry (S pO2 ) is nowadays the standard clinical method for assessing arterial oxygen saturation, providing a convenient, pain-free means of continuously assessing oxygenation, provided the interpreting clinician is aware of important limitations. The use of pulse oximetry reduces the need for arterial blood gas analysis (S aO2 ) as many patients who are not at risk of hypercapnic respiratory failure or metabolic acidosis and have acceptable S pO2 do not necessarily require blood gas analysis. While arterial sampling remains the gold-standard method of assessing ventilation and oxygenation, in those patients in whom blood gas analysis is indicated, arterialised capillary samples also have a valuable role in patient care. The clinical role of venous blood gases however remains less well defined.

Relating oxygen partial pressure, saturation and content: the haemoglobin–oxygen dissociation curve

Directory of Open Access Journals (Sweden)

Julie-Ann Collins

2015-09-01

The delivery of oxygen by arterial blood to the tissues of the body has a number of critical determinants including blood oxygen concentration (content, saturation (SO2 and partial pressure, haemoglobin concentration and cardiac output, including its distribution. The haemoglobin–oxygen dissociation curve, a graphical representation of the relationship between oxygen satur­ation and oxygen partial pressure helps us to understand some of the principles underpinning this process. Historically this curve was derived from very limited data based on blood samples from small numbers of healthy subjects which were manipulated in vitro and ultimately determined by equations such as those described by Severinghaus in 1979. In a study of 3524 clinical specimens, we found that this equation estimated the SO2 in blood from patients with normal pH and SO2 >70% with remarkable accuracy and, to our knowledge, this is the first large-scale validation of this equation using clinical samples. Oxygen saturation by pulse oximetry (SpO2 is nowadays the standard clinical method for assessing arterial oxygen saturation, providing a convenient, pain-free means of continuously assessing oxygenation, provided the interpreting clinician is aware of important limitations. The use of pulse oximetry reduces the need for arterial blood gas analysis (SaO2 as many patients who are not at risk of hypercapnic respiratory failure or metabolic acidosis and have acceptable SpO2 do not necessarily require blood gas analysis. While arterial sampling remains the gold-standard method of assessing ventilation and oxygenation, in those patients in whom blood gas analysis is indicated, arterialised capillary samples also have a valuable role in patient care. The clinical role of venous blood gases however remains less well defined.

What is the manner of gastric emptying after ingestion of liquids with differences in the volume under uniform glucose-based energy content?

Science.gov (United States)

Okabe, Tadashi; Terashima, Hideo; Sakamoto, Atsuhiro

2017-10-01

We previously demonstrated that the gastric emptying rate of liquids chiefly depended on the total amount of calories (energy content) in a uniform volume. The aim of the present study was to examine the effects of different volumes of liquids with a uniform energy content on gastric emptying. Three types of test solutions were prepared with a uniform amount of calories (200 kcal provided by glucose) and step-wise increments in volume (200 ml, 400 ml, and 600 ml). The gastric volume of each solution was determined by ultrasound measurements of the gastric antral cross-sectional area after their ingestion by 8 healthy volunteers. The mean gastric volume decreased exponentially to nearly 0 ml 70 min after ingestion in the 200 ml group, 90 min in the 400 ml group, and 100 min in the 600 ml group. Each gastric emptying curve converged with identical slopes on the graph when the points at which the gastric emptying curves of the 200 ml and 400 ml groups reached the zero point on the Y-axis (mean gastric volume) were shifted toward 110 min on the X-axis (time scale). The volume of liquid ingested with a uniform glucose-based energy content is a critical determinant of liquid gastric emptying. The gastric emptying time may be predicted following the ingestion of an isocaloric liquid with any volume over a predefined range once a gastric emptying curve following the ingestion of a liquid has been plotted on a graph. UMIN000014930. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

A novel method for the angiographic estimation of the percentage of spleen volume embolized during partial splenic embolization

International Nuclear Information System (INIS)

Ou, Ming-Ching; Chuang, Ming-Tsung; Lin, Xi-Zhang; Tsai, Hong-Ming; Chen, Shu-Yuan; Liu, Yi-Sheng

2013-01-01

Purpose: To evaluate the efficacy of estimating the volume of spleen embolized in partial splenic embolization (PSE) by measuring the diameters of the splenic artery and its branches. Materials and methods: A total of 43 liver cirrhosis patients (mean age, 62.19 ± 9.65 years) with thrombocytopenia were included. Among these, 24 patients underwent a follow-up CT scan which showed a correlation between angiographic estimation and measured embolized splenic volume. Estimated splenic embolization volume was calculated by a method based on diameters of the splenic artery and its branches. The diameters of each of the splenic arteries and branches were measured via 2D angiographic images. Embolization was performed with gelatin sponges. Patients underwent follow-up with serial measurement of blood counts and liver function tests. The actual volume of embolized spleen was determined by computed tomography (CT) measuring the volumes of embolized and non-embolized spleen two months after PSE. Results: PSE was performed without immediate major complications. The mean WBC count significantly increased from 3.81 ± 1.69 × 10 3 /mm 3 before PSE to 8.56 ± 3.14 × 10 3 /mm 3 at 1 week after PSE (P < 0.001). Mean platelet count significantly increased from 62.00 ± 22.62 × 10 3 /mm 3 before PSE to 95.40 ± 46.29 × 10 3 /mm 3 1 week after PSE (P < 0.001). The measured embolization ratio was positively correlated with estimated embolization ratio (Spearman's rho [ρ] = 0.687, P < 0.001). The mean difference between the actual embolization ratio and the estimated embolization ratio was 16.16 ± 8.96%. Conclusions: The method provides a simple method to quantitatively estimate embolized splenic volume with a correlation of measured embolization ratio to estimated embolization ratio of Spearman's ρ = 0.687

Kalisphera: an analytical tool to reproduce the partial volume effect of spheres imaged in 3D

International Nuclear Information System (INIS)

Tengattini, Alessandro; Andò, Edward

2015-01-01

In experimental mechanics, where 3D imaging is having a profound effect, spheres are commonly adopted for their simplicity and for the ease of their modeling. In this contribution we develop an analytical tool, ‘kalisphera’, to produce 3D raster images of spheres including their partial volume effect. This allows us to evaluate the metrological performance of existing image-based measurement techniques (knowing a priori the ground truth). An advanced application of ‘kalisphera’ is developed here to identify and accurately characterize spheres in real 3D x-ray tomography images with the objective of improving trinarization and contact detection. The effect of the common experimental imperfections is assessed and the overall performance of the tool tested on real images. (paper)

Partial molar volumes of organic solutes in water. XXIII. Cyclic ketones at T = (298 to 573) K and pressures up to 30 MPa

International Nuclear Information System (INIS)

Cibulka, Ivan; Simurka, Lukas; Hnedkovsky, Lubomir; Bolotov, Alexander

2011-01-01

Research highlights: → In this study we examine standard molar volumes of aqueous cyclic ketones. → State parameters of measurements were (298 to 573) K and pressures up to 30 MPa. → Differences in behavior of monoketones and cyclohexane-1,4-dione were observed. → Group contribution method was designed and examined. - Abstract: Density data for dilute aqueous solutions of four cyclic ketones (cyclopentanone, cyclohexanone, cycloheptanone, and cyclohexane-1,4-dione) are presented together with standard molar volumes (partial molar volumes at infinite dilution) calculated from the experimental data. The measurements were performed at temperatures from T = 298 K up to T = 573 K. Experimental pressures were close to the saturated vapor pressure of water, and (15 and 30) MPa. The data were obtained using a high-temperature high-pressure flow vibrating-tube densimeter. Experimental standard molar volumes were correlated as a function of temperature and pressure using an empirical polynomial function. Contributions of the molecular structural segments (methylene and carbonyl groups) to the standard molar volume were also evaluated and analyzed.

Dissociation of the effects of preload volume and energy content on subjective appetite and food intake.

Science.gov (United States)

Gray, Richard; French, Stephen; Robinson, Tristan; Yeomans, Martin

2002-05-01

Previous research suggests that enhancing the volume of a food preload without altering energy content can result in reduced appetite, although the limited evidence means that the conditions under which this effect will occur are not yet clear. In the present study, we used a Universal Eating Monitor (UEM) to record test meal intake constantly, in parallel with appetite ratings, following soup-based preloads that varied both in volume (150 vs. 450 ml) and energy density (1.4 vs. 4.2 kJ/ml). Healthy young men (n=20) received four different preload conditions (repeated measures) followed by unlimited hot pasta test meals (interval 30 min). They completed appetite ratings during and after each laboratory session, and food diaries for the afternoon and evening following each session. Subjective appetite after the preloads was reduced by the high-volume preloads relative to low-volume preloads, with no difference between the two at each volume level. This indicates an effect of volume, but no effect of energy. Test meal intake in the high-volume, high-energy-density condition was reduced relative to the other conditions, which did not differ from one another. This indicates an effect of total energy, but no effect of volume. The dissociation between these different measures of appetite might be explained in terms of largely cognitive influences on subjective appetite between preload and test meal, contrasted with stronger physiological influences on actual intake during the test meal. With regard to previous studies, it is argued that food volume is more influential under circumstances where gastric volume is closer to its normal limits.

Aqueous partial molar heat capacities and volumes for NaReO4 and NaTcO4

International Nuclear Information System (INIS)

Lemire, R.J.; Saluja, P.P.S.; Campbell, A.B.

1989-01-01

As part of the Canadian Nuclear Fuel Waste Management Program, data are required to model the equilibrium thermodynamic behavior of key radionuclides at temperatures above 25 degree C. A flow microcalorimeter/densimeter system has been commissioned to measure heat capacities and densities of solutions containing radioactive species. Measurements for solutions of aqueous NaReO 4 (a common analogue for NaTcO 4 ) were made at seven temperatures (15 to 100 degree C) over the concentration range 0.05 to 0.2 mol·kg -1 . Subsequently, measurements were made for NaTcO 4 solutions under similar conditions. The heat capacity and density data are analyzed using Pitzer's ion-interaction model, and values of the NaReO 4 partial molar heat capacities are compared to literature values based on integral heats of solution. The agreement between the two sets of NaReO 4 data is good below 75 degree C, but only fair at the higher temperatures. Values of the partial molar volumes have also been derived. The uncertainties introduced by using thermodynamic data for ReO 4 - , in the absence of data for TcO 4 - , are discussed

Different partial volume correction methods lead to different conclusions: An (18)F-FDG-PET study of aging.

Science.gov (United States)

Greve, Douglas N; Salat, David H; Bowen, Spencer L; Izquierdo-Garcia, David; Schultz, Aaron P; Catana, Ciprian; Becker, J Alex; Svarer, Claus; Knudsen, Gitte M; Sperling, Reisa A; Johnson, Keith A

2016-05-15

A cross-sectional group study of the effects of aging on brain metabolism as measured with (18)F-FDG-PET was performed using several different partial volume correction (PVC) methods: no correction (NoPVC), Meltzer (MZ), Müller-Gärtner (MG), and the symmetric geometric transfer matrix (SGTM) using 99 subjects aged 65-87years from the Harvard Aging Brain study. Sensitivity to parameter selection was tested for MZ and MG. The various methods and parameter settings resulted in an extremely wide range of conclusions as to the effects of age on metabolism, from almost no changes to virtually all of cortical regions showing a decrease with age. Simulations showed that NoPVC had significant bias that made the age effect on metabolism appear to be much larger and more significant than it is. MZ was found to be the same as NoPVC for liberal brain masks; for conservative brain masks, MZ showed few areas correlated with age. MG and SGTM were found to be similar; however, MG was sensitive to a thresholding parameter that can result in data loss. CSF uptake was surprisingly high at about 15% of that in gray matter. The exclusion of CSF from SGTM and MG models, which is almost universally done, caused a substantial loss in the power to detect age-related changes. This diversity of results reflects the literature on the metabolism of aging and suggests that extreme care should be taken when applying PVC or interpreting results that have been corrected for partial volume effects. Using the SGTM, significant age-related changes of about 7% per decade were found in frontal and cingulate cortices as well as primary visual and insular cortices. Copyright © 2016 Elsevier Inc. All rights reserved.

Different Partial Volume Correction Methods Lead to Different Conclusions: an 18F-FDG PET Study of Aging

Science.gov (United States)

Greve, Douglas N.; Salat, David H.; Bowen, Spencer L.; Izquierdo-Garcia, David; Schultz, Aaron P.; Catana, Ciprian; Becker, J. Alex; Svarer, Claus; Knudsen, Gitte; Sperling, Reisa A.; Johnson, Keith A.

2016-01-01

A cross-sectional group study of the effects of aging on brain metabolism as measured with 18F-FDG PET was performed using several different partial volume correction (PVC) methods: no correction (NoPVC), Meltzer (MZ), Müller-Gärtner (MG), and the symmetric geometric transfer matrix (SGTM) using 99 subjects aged 65-87 from the Harvard Aging Brain study. Sensitivity to parameter selection was tested for MZ and MG. The various methods and parameter settings resulted in an extremely wide range of conclusions as to the effects of age on metabolism, from almost no changes to virtually all of cortical regions showing a decrease with age. Simulations showed that NoPVC had significant bias that made the age effect on metabolism appear to be much larger and more significant than it is. MZ was found to be the same as NoPVC for liberal brain masks; for conservative brain masks, MZ showed few areas correlated with age. MG and SGTM were found to be similar; however, MG was sensitive to a thresholding parameter that can result in data loss. CSF uptake was surprisingly high at about 15% of that in gray matter. Exclusion of CSF from SGTM and MG models, which is almost universally done, caused a substantial loss in the power to detect age-related changes. This diversity of results reflects the literature on the metabolism of aging and suggests that extreme care should be taken when applying PVC or interpreting results that have been corrected for partial volume effects. Using the SGTM, significant age-related changes of about 7% per decade were found in frontal and cingulate cortices as well as primary visual and insular cortices. PMID:26915497

Experimental study of the density and derived volumetric (excess, apparent, and partial molar volumes) properties of aqueous 1-propanol mixtures at temperatures from 298 K to 582 K and pressures up to 40 MPa

International Nuclear Information System (INIS)

Abdulagatov, I.M.; Azizov, N.D.

2014-01-01

Highlights: • Density of (water + 1-propanol) mixtures. • Excess molar volumes of (water + 1-propanol) mixtures. • Apparent molar volumes of (water + 1-propanol) mixtures. -- Abstract: Densities of (water + 1-propanol) mixtures have been measured over the temperature range from 298 K to 582 K and at pressures up to 40 MPa using the constant-volume piezometer immersed in a precision liquid thermostat. The measurements were made for six compositions of (0.869, 2.465, 2.531, 7.407, 14.377, and 56.348) mol · kg −1 of 1-propanol. The expanded uncertainty of the density, pressure, temperature, and concentration measurements at the 95% confidence level with a coverage factor of k = 2 is estimated to be 0.06%, 0.05%, 15 mK, and 0.015%, respectively. The derived volumetric properties such as excess (V m E ), apparent (V Φ ), and partial (V ¯ 2 ∞ ) molar volumes were calculated using the measured values of density for the mixture and for pure components (water and 1-propanol). The concentration dependences of the apparent molar volumes were extrapolated to zero concentration to yield the partial molar volumes of 1-propanol at infinite dilution (V ¯ 2 ∞ ). The temperature, pressure, and concentration dependence of density and derived properties of the mixture were studied. All experimental and derived properties (excess, apparent, and partial molar volumes) were compared with the reported data by other authors. The small and negative values of excess molar volume for the mixtures were found at all experimental temperatures, pressures, and over the entire concentration range. The excess molar volume minimum is found at concentration about 0.4 mole fraction of 1-propanol. The concentration minimum of the derived apparent molar volumes V Φ near the 2.5 mol · kg −1 (dilute mixture) was observed

The component content of active particles in a plasma-chemical reactor based on volume barrier discharge

Science.gov (United States)

Soloshenko, I. A.; Tsiolko, V. V.; Pogulay, S. S.; Terent'yeva, A. G.; Bazhenov, V. Yu; Shchedrin, A. I.; Ryabtsev, A. V.; Kuzmichev, A. I.

2007-02-01

In this paper the results of theoretical and experimental studies of the component content of active particles formed in a plasma-chemical reactor composed of a multiple-cell generator of active particles, based on volume barrier discharge, and a working chamber are presented. For calculation of the content of uncharged plasma components an approach is proposed which is based on averaging of the power introduced over the entire volume. Advantages of such an approach lie in an absence of fitting parameters, such as the dimensions of microdischarges, their surface density and rate of breakdown. The calculation and the experiment were accomplished with the use of dry air (20% relative humidity) as the plasma generating medium. Concentrations of O3, HNO3, HNO2, N2 O5 and NO3 were measured experimentally in the discharge volume and working chamber for the residence time of particles on a discharge of 0.3 s and more and discharge specific power of 1.5 W cm-3. It has been determined that the best agreement between the calculation and the experiment occurs at calculated gas medium temperatures in the discharge plasma of about 400-425 K, which correspond to the experimentally measured rotational temperature of nitrogen. In most cases the calculated concentrations of O3, HNO3, HNO2, N2O5 and NO3 for the barrier discharge and the working chamber are in fairly good agreement with the respective measured values.

The component content of active particles in a plasma-chemical reactor based on volume barrier discharge

International Nuclear Information System (INIS)

Soloshenko, I A; Tsiolko, V V; Pogulay, S S; Terent'yeva, A G; Bazhenov, V Yu; Shchedrin, A I; Ryabtsev, A V; Kuzmichev, A I

2007-01-01

In this paper the results of theoretical and experimental studies of the component content of active particles formed in a plasma-chemical reactor composed of a multiple-cell generator of active particles, based on volume barrier discharge, and a working chamber are presented. For calculation of the content of uncharged plasma components an approach is proposed which is based on averaging of the power introduced over the entire volume. Advantages of such an approach lie in an absence of fitting parameters, such as the dimensions of microdischarges, their surface density and rate of breakdown. The calculation and the experiment were accomplished with the use of dry air (20% relative humidity) as the plasma generating medium. Concentrations of O 3 , HNO 3 , HNO 2 , N 2 O 5 and NO 3 were measured experimentally in the discharge volume and working chamber for the residence time of particles on a discharge of 0.3 s and more and discharge specific power of 1.5 W cm -3 . It has been determined that the best agreement between the calculation and the experiment occurs at calculated gas medium temperatures in the discharge plasma of about 400-425 K, which correspond to the experimentally measured rotational temperature of nitrogen. In most cases the calculated concentrations of O 3 , HNO 3 , HNO 2 , N 2 O 5 and NO 3 for the barrier discharge and the working chamber are in fairly good agreement with the respective measured values

Effect of temperature on the partial molar volume, isentropic compressibility and viscosity of DL-2-aminobutyric acid in water and in aqueous sodium chloride solutions

International Nuclear Information System (INIS)

Romero, Carmen M.; Rodríguez, Diana M.; Ribeiro, Ana C.F.; Esteso, Miguel A.

2017-01-01

Highlights: • Apparent volumes, apparent compressibilities, viscosities of DL-2-aminobutyric acid. • Effect of temperature on the values for these properties. • Hydrophobic and hydrophilic interactions and the effect of sodium chloride. - Abstract: Density, sound velocity and viscosity of DL-2-aminobutyric acid in water and in aqueous sodium chloride solutions have been measured at temperatures of (293.15, 298.15, 303.15, 308.15 and 313.15) K. The experimental results were used to determine the apparent molar volume and the apparent molar compressibility as a function of composition at these temperatures. The limiting values of both the partial molar volume and the partial molar adiabatic compressibility at infinite dilution of DL-2-aminobutyric acid in water and in aqueous sodium chloride solutions were determined at each temperature. The experimental viscosity values were adjusted by a least-squares method to a second order equation as proposed by Tsangaris-Martin to obtain the viscosity B coefficient which depends on the size, shape and charge of the solute molecule. The influence of the temperature on the behaviour of the selected properties is discussed in terms of both the solute hydration and the balance between hydrophobic and hydrophilic interactions between the acids and water, and the effect of the sodium chloride concentration.

Elements of partial differential equations

CERN Document Server

Sneddon, Ian Naismith

1957-01-01

Geared toward students of applied rather than pure mathematics, this volume introduces elements of partial differential equations. Its focus is primarily upon finding solutions to particular equations rather than general theory.Topics include ordinary differential equations in more than two variables, partial differential equations of the first and second orders, Laplace's equation, the wave equation, and the diffusion equation. A helpful Appendix offers information on systems of surfaces, and solutions to the odd-numbered problems appear at the end of the book. Readers pursuing independent st

Effect of water content on partial ternary phase diagram water-in-diesel microemulsion fuel

Science.gov (United States)

Mukayat, Hastinatun; Badri, Khairiah Haji; Raman, Ismail Ab.; Ramli, Suria

2014-09-01

Introduction of water in the fuel gave a significant effect to the reduction of pollutant such as NOx emission. In this work, water/diesel microemulsion fuels were prepared using compositional method by mixing water and diesel in the presence of non-ionic surfactant and co-surfactant. The effects of water composition on the partial ternary phase diagram were studied at 5%, 10%, 15% and 20% (w/w). The physical stability of the microemulsion was investigated at 45°C over a period of one month. The optimum formulae obtained were diesel/T80/1-penthanol/water 60:20:15:5 wt% (System 1), 55:20:15:10 wt% (System 2), 50:20:15:15 wt% (System 3) and 45:20:15:20 wt% (System 4). Physicochemical characterizations of optimum formulae were studied. The results showed that water content has a significant effect to the formation of microemulsion, its stability, droplet size and viscosity.

First-order partial differential equations

CERN Document Server

Rhee, Hyun-Ku; Amundson, Neal R

2001-01-01

This first volume of a highly regarded two-volume text is fully usable on its own. After going over some of the preliminaries, the authors discuss mathematical models that yield first-order partial differential equations; motivations, classifications, and some methods of solution; linear and semilinear equations; chromatographic equations with finite rate expressions; homogeneous and nonhomogeneous quasilinear equations; formation and propagation of shocks; conservation equations, weak solutions, and shock layers; nonlinear equations; and variational problems. Exercises appear at the end of mo

Chiral and continuum extrapolation of partially quenched lattice results

Energy Technology Data Exchange (ETDEWEB)

C.R. Allton; W. Armour; D.B. Leinweber; A.W. Thomas; R.D. Young

2005-04-01

The vector meson mass is extracted from a large sample of partially quenched, two-flavor lattice QCD simulations. For the first time, discretization, finite-volume and partial quenching artifacts are treated in a unified chiral effective field theory analysis of the lattice simulation results.

Hydrophobic hydration and anomalous excess partial molar volume of tert-butyl alcohol-water mixture studied by quasielastic neutron scattering

International Nuclear Information System (INIS)

Nakada, Masaru; Maruyama, Kenji; Misawa, Masakatsu; Yamamuro, Osamu

2007-01-01

Quasielastic neutron scattering has been used to investigate the hydration of alcohol clusters in tert-butyl alcohol-water mixture. The measurements were made in a range of alcohol concentration, x TBA , from 0.0 to 0.17 in mole fraction at 25degC. Fraction, α, of water molecules hydrated to fractal-surface of alcohol clusters in tert-butyl alcohol-water mixture was obtained as a function of alcohol concentration. Average hydration number N WS of tert-butyl alcohol molecule was derived from the value of α as a function of alcohol concentration. The value of N WS for an isolated alcohol molecule in water was 19-21. The anomalous excess partial molar volume of tert-butyl alcohol-water mixture was interpreted successfully by applying the same model with the same values of volume parameter as used for 1-propanol-water mixture, δ 1 (=-0.36 cm 3 ·mol -1 ) and δ 2 (=0.60 cm 3 ·mol -1 ). (author)

Effects of respiratory rate and tidal volume on gas exchange in total liquid ventilation.

Science.gov (United States)

Bull, Joseph L; Tredici, Stefano; Fujioka, Hideki; Komori, Eisaku; Grotberg, James B; Hirschl, Ronald B

2009-01-01

Using a rabbit model of total liquid ventilation (TLV), and in a corresponding theoretical model, we compared nine tidal volume-respiratory rate combinations to identify a ventilator strategy to maximize gas exchange, while avoiding choked flow, during TLV. Nine different ventilation strategies were tested in each animal (n = 12): low [LR = 2.5 breath/min (bpm)], medium (MR = 5 bpm), or high (HR = 7.5 bpm) respiratory rates were combined with a low (LV = 10 ml/kg), medium (MV = 15 ml/kg), or high (HV = 20 ml/kg) tidal volumes. Blood gases and partial pressures, perfluorocarbon gas content, and airway pressures were measured for each combination. Choked flow occurred in all high respiratory rate-high volume animals, 71% of high respiratory rate-medium volume (HRMV) animals, and 50% of medium respiratory rate-high volume (MRHV) animals but in no other combinations. Medium respiratory rate-medium volume (MRMV) resulted in the highest gas exchange of the combinations that did not induce choke. The HRMV and MRHV animals that did not choke had similar or higher gas exchange than MRMV. The theory predicted this behavior, along with spatial and temporal variations in alveolar gas partial pressures. Of the combinations that did not induce choked flow, MRMV provided the highest gas exchange. Alveolar gas transport is diffusion dominated and rapid during gas ventilation but is convection dominated and slow during TLV. Consequently, the usual alveolar gas equation is not applicable for TLV.

Plasma volume changes during hypoglycaemia

DEFF Research Database (Denmark)

Hilsted, J; Bendtsen, F; Christensen, N J

1990-01-01

To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

Effects of retained austenite volume fraction, morphology, and carbon content on strength and ductility of nanostructured TRIP-assisted steels

Energy Technology Data Exchange (ETDEWEB)

Shen, Y.F., E-mail: shenyf@smm.neu.edu.cn [Key Laboratory for Anisotropy and Texture of Materials (MOE), Northeastern University, 3 Wenhua Road, Shenyang 110004 (China); Qiu, L.N. [Key Laboratory for Anisotropy and Texture of Materials (MOE), Northeastern University, 3 Wenhua Road, Shenyang 110004 (China); Sun, X. [Pacific Northwest National Laboratory, PO Box 999, Richland, WA 99352 (United States); Zuo, L. [Key Laboratory for Anisotropy and Texture of Materials (MOE), Northeastern University, 3 Wenhua Road, Shenyang 110004 (China); Liaw, P.K. [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN 37996 (United States); Raabe, D. [Max-Planck-Institut fuer Eisenforschung, Max-Planck-Str. 1, 8, 40237 Düsseldorf (Germany)

2015-06-11

With a suite of multi-modal and multi-scale characterization techniques, the present study unambiguously proves that a substantially-improved combination of ultrahigh strength and good ductility can be achieved by tailoring the volume fraction, morphology, and carbon content of the retained austenite (RA) in a transformation-induced-plasticity (TRIP) steel with the nominal chemical composition of 0.19C–0.30Si–1.76Mn–1.52Al (weight percent, wt%). After intercritical annealing and bainitic holding, a combination of ultimate tensile strength (UTS) of 1100 MPa and true strain of 50% has been obtained, as a result of the ultrafine RA lamellae, which are alternately arranged in the bainitic ferrite around junction regions of ferrite grains. For reference, specimens with a blocky RA, prepared without the bainitic holding, yield a low ductility (35%) and a low UTS (800 MPa). The volume fraction, morphology, and carbon content of RA have been characterized using various techniques, including the magnetic probing, scanning electron microscopy (SEM), electron-backscatter-diffraction (EBSD), and transmission electron microscopy (TEM). Interrupted tensile tests, mapped using EBSD in conjunction with the kernel average misorientation (KAM) analysis, reveal that the lamellar RA is the governing microstructure component responsible for the higher mechanical stability, compared to the blocky one. By coupling these various techniques, we quantitatively demonstrate that in addition to the RA volume fraction, its morphology and carbon content are equally important in optimizing the strength and ductility of TRIP-assisted steels.

Solubilities and partial molar volumes of N,N′-dibutyl-oxalamide, N,N′-dihexyl-oxalamide, N,N′-dioctyl-oxalamide in supercritical carbon dioxide

International Nuclear Information System (INIS)

Luo, Jie; Yang, Hai-Jian; Jin, Jing; Chang, Fei

2012-01-01

Highlights: ► Three new “CO 2 -philic” compounds were designed and synthesized. ► The tested solubility data were calculated and correlated with two models. ► Satisfactory agreements were obtained between the tested and calculated data. ► AARD was lower than 13% for Chrastil model correlation. ► The partial molar volumes V ¯ 2 for each compound were estimated. - Abstract: Three new potent CO 2 -philic compounds were synthesized and their structures were characterized by FT-IR, NMR, and elemental analysis. The solubility of the three compounds in supercritical CO 2 was determined at T = (313 to 353) K from 9.1 MPa to 15.0 MPa. The experimental data were correlated with two density-based models proposed by Bartle and Chrastil, and the calculated results showed good agreement with the tested data. The calculated data by Bartle model differed from the measured values by (6.76 to 9.60)%, and the average value of absolute relative deviations (AARD) with Chrastil model were observed to be between (7.42 to 12.27)%. Furthermore, solubility data were also utilized to estimate the partial molar volume V ¯ 2 for each compound in the supercritical phase using the theory developed by Kumar and Johnston.

The Investigation on Flexural Toughness of Partially Steel Fiber Reinforced Concrete Immersed by Simulated Sea-Water

Directory of Open Access Journals (Sweden)

Feng GAO

2017-11-01

Full Text Available In order to investigate the corrosive resistance of partially steel fiber reinforced concrete (PSFRC, the flexural toughness experiment of nine specimens subjected to corrosion by alternating wet and dry cycles in a simulated marine environment were conducted, which aims at investigating the effect of corrosion time, steel fiber volume fraction and SFRC thickness on PSFRC toughness. The experimental results showed that both the mechanical and ductile characteristics of PSFRC got worse due to corrosion even if increasing the steel fiber volume. Additionally, the effect of steel fiber content on the toughness and ultimate load are greater than PSFRC thickness (t. The increase of 56.6% and 171% could be obtained in the mean ultimate load and I10 if the increase of steel fiber volume is from 0.5 % to 2.0%, respectively. This paper could offer a reference to the application of PSFRC in sea-water environment.DOI: http://dx.doi.org/10.5755/j01.ms.23.4.17049

A novel method for the angiographic estimation of the percentage of spleen volume embolized during partial splenic embolization

Energy Technology Data Exchange (ETDEWEB)

Ou, Ming-Ching; Chuang, Ming-Tsung [Department of Diagnostic Radiology, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China); Lin, Xi-Zhang [Department of Internal Medicine, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China); Tsai, Hong-Ming; Chen, Shu-Yuan [Department of Diagnostic Radiology, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China); Liu, Yi-Sheng, E-mail: taicheng100704@yahoo.com.tw [Department of Diagnostic Radiology, National Cheng-Kung University Hospital, No. 138 Sheng Li Road, Tainan 704, Taiwan, ROC (China)

2013-08-15

Purpose: To evaluate the efficacy of estimating the volume of spleen embolized in partial splenic embolization (PSE) by measuring the diameters of the splenic artery and its branches. Materials and methods: A total of 43 liver cirrhosis patients (mean age, 62.19 ± 9.65 years) with thrombocytopenia were included. Among these, 24 patients underwent a follow-up CT scan which showed a correlation between angiographic estimation and measured embolized splenic volume. Estimated splenic embolization volume was calculated by a method based on diameters of the splenic artery and its branches. The diameters of each of the splenic arteries and branches were measured via 2D angiographic images. Embolization was performed with gelatin sponges. Patients underwent follow-up with serial measurement of blood counts and liver function tests. The actual volume of embolized spleen was determined by computed tomography (CT) measuring the volumes of embolized and non-embolized spleen two months after PSE. Results: PSE was performed without immediate major complications. The mean WBC count significantly increased from 3.81 ± 1.69 × 10{sup 3}/mm{sup 3} before PSE to 8.56 ± 3.14 × 10{sup 3}/mm{sup 3} at 1 week after PSE (P < 0.001). Mean platelet count significantly increased from 62.00 ± 22.62 × 10{sup 3}/mm{sup 3} before PSE to 95.40 ± 46.29 × 10{sup 3}/mm{sup 3} 1 week after PSE (P < 0.001). The measured embolization ratio was positively correlated with estimated embolization ratio (Spearman's rho [ρ] = 0.687, P < 0.001). The mean difference between the actual embolization ratio and the estimated embolization ratio was 16.16 ± 8.96%. Conclusions: The method provides a simple method to quantitatively estimate embolized splenic volume with a correlation of measured embolization ratio to estimated embolization ratio of Spearman's ρ = 0.687.

Anatomic partial nephrectomy: technique evolution.

Science.gov (United States)

Azhar, Raed A; Metcalfe, Charles; Gill, Inderbir S

2015-03-01

Partial nephrectomy provides equivalent long-term oncologic and superior functional outcomes as radical nephrectomy for T1a renal masses. Herein, we review the various vascular clamping techniques employed during minimally invasive partial nephrectomy, describe the evolution of our partial nephrectomy technique and provide an update on contemporary thinking about the impact of ischemia on renal function. Recently, partial nephrectomy surgical technique has shifted away from main artery clamping and towards minimizing/eliminating global renal ischemia during partial nephrectomy. Supported by high-fidelity three-dimensional imaging, novel anatomic-based partial nephrectomy techniques have recently been developed, wherein partial nephrectomy can now be performed with segmental, minimal or zero global ischemia to the renal remnant. Sequential innovations have included early unclamping, segmental clamping, super-selective clamping and now culminating in anatomic zero-ischemia surgery. By eliminating 'under-the-gun' time pressure of ischemia for the surgeon, these techniques allow an unhurried, tightly contoured tumour excision with point-specific sutured haemostasis. Recent data indicate that zero-ischemia partial nephrectomy may provide better functional outcomes by minimizing/eliminating global ischemia and preserving greater vascularized kidney volume. Contemporary partial nephrectomy includes a spectrum of surgical techniques ranging from conventional-clamped to novel zero-ischemia approaches. Technique selection should be tailored to each individual case on the basis of tumour characteristics, surgical feasibility, surgeon experience, patient demographics and baseline renal function.

Function spaces and partial differential equations 2 volume set

CERN Document Server

Taheri, Ali

2015-01-01

This is a book written primarily for graduate students and early researchers in the fields of Analysis and Partial Differential Equations (PDEs). Coverage of the material is essentially self-contained, extensive and novel with great attention to details and rigour.

The Partial Molar Volume and Compressibility of FeO in CaO-SiO2 Liquids: Systematic Variation with Fe2+ Coordination Change

Science.gov (United States)

Guo, X.; Lange, R. A.; Ai, Y.

2009-12-01

Iron is an important element in magmatic liquid, since its concentration can range up to 18% in some basaltic liquids, and it has two oxidation states. In order to model magmatic processes, thermodynamic descriptions of silicate melts must include precise information for both the FeO and Fe2O3 components. Currently, the partial molar volume of FeO is not as well known as that for Fe2O3 because of the difficulty of performing double-bob density measurements under reducing conditions. Yet these data are required in order to convert sound speed measurements on FeO-bearing liquids into compressibility data, which in turn are needed extend density models for magmatic liquids to elevated pressures. Moreover, there is growing evidence from the spectroscopic literature that Fe2+ occurs in 4, 5, and 6-fold coordination in silicate melts, and thus it is possible that the partial molar volume and compressibility of FeO may vary with Fe2+ coordination, and thus with melt composition. To explore these issues, we have conducted both density and relaxed sound speed measurements on liquids in the CaO-FeO-SiO2 system, where the CaO/SiO2 ratio was systematically varied at constant FeO concentration (40 mol%). Density was measured between 1594 and 1813K with the double-bob Archimedean method using molybdenum bobs and crucible in a reducing gas (1%CO-99%Ar) environment. The sounds speeds were measured under similar conditions with a frequency-sweep acoustic interferometer. The derived partial molar volume of FeO increases systematically from 13.7 to 15.2 cm3/mol at 1673 K as the CaO/SiO2 ratio increases and the Fe2+ coordination number decreases. From a comparison with the crystalline volume of FeO (halite structure; 12.06 cm3/mol), which serves as a lower limit for VFeO in silicate liquids when Fe2+ is in 6-fold coordination, we estimate that the average Fe2+ coordination in our experimental melts extends up to values between 5 and 4, consistent with the spectroscopic literature. The

Partial volume effect-corrected FDG PET and grey matter volume loss in patients with mild Alzheimer's disease

International Nuclear Information System (INIS)

Samuraki, Miharu; Yanase, Daisuke; Yamada, Masahito; Matsunari, Ichiro; Chen, Wei-Ping; Yajima, Kazuyoshi; Fujikawa, Akihiko; Takeda, Nozomi; Nishimura, Shintaro; Matsuda, Hiroshi

2007-01-01

Although 18 F-fluorodeoxyglucose (FDG) PET is an established imaging technique to assess brain glucose utilisation, accurate measurement of tracer concentration is confounded by the presence of partial volume effect (PVE) due to the limited spatial resolution of PET, which is particularly true in atrophic brains such as those encountered in patients with Alzheimer's disease (AD). Our aim was to investigate the effects of PVE correction on FDG PET in conjunction with voxel-based morphometry (VBM) in patients with mild AD. Thirty-nine AD patients and 73 controls underwent FDG PET and MRI. The PVE-corrected grey matter PET images were obtained using an MRI-based three-compartment method. Additionally, the results of PET were compared with grey matter loss detected by VBM. Before PVE correction, reduced FDG uptake was observed in posterior cingulate gyri (PCG) and parieto-temporal lobes (PTL) in AD patients, which persisted after PVE correction. Notably, PVE correction revealed relatively preserved FDG uptake in hippocampal areas, despite the grey matter loss in medial temporal lobe (MTL) revealed by VBM. FDG uptake in PCG and PTL is reduced in AD regardless of whether or not PVE correction is applied, supporting the notion that the reduced FDG uptake in these areas is not the result of atrophy. Furthermore, FDG uptake by grey matter tissue in the MTL, including hippocampal areas, is relatively preserved, suggesting that compensatory mechanisms may play a role in patients with mild AD. (orig.)

Degradation of self-compacting concrete (SCC) due to sulfuric acid attack: Experiment investigation on the effect of high volume fly ash content

Science.gov (United States)

Kristiawan, S. A.; Sunarmasto; Tyas, G. P.

2016-02-01

Concrete is susceptible to a variety of chemical attacks. In the sulfuric acid environment, concrete is subjected to a combination of sulfuric and acid attack. This research is aimed to investigate the degradation of self-compacting concrete (SCC) due to sulfuric acid attack based on measurement of compressive strength loss and diameter change. Since the proportion of SCC contains higher cement than that of normal concrete, the vulnerability of this concrete to sulfuric acid attack could be reduced by partial replacement of cement with fly ash at high volume level. The effect of high volume fly ash at 50-70% cement replacement levels on the extent of degradation owing to sulfuric acid will be assessed in this study. It can be shown that an increase in the utilization of fly ash to partially replace cement tends to reduce the degradation as confirmed by less compressive strength loss and diameter change. The effect of fly ash to reduce the degradation of SCC is more pronounced at a later age.

Water Resources Data for California, Water Year 1985. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

Science.gov (United States)

Bowers, J.C.; McConaughy, C.E.; Polinoski, K.G.; Smith, G.B.

1987-01-01

Water resources data for the 1985 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 150 gaging stations; stage and contents for 17 lakes and reservoirs; water quality for 23 streams. Also included are 10 crest-stage partial-record stations, three miscellaneous measurement sites, and one waterquality partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

Water Resources Data for California, Water Year 1986. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

Science.gov (United States)

Bowers, J.C.; McConaughy, C.E.; Polinoski, K.G.; Smith, G.B.

1988-01-01

Water resources data for the 1986 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 144 gaging stations; stage and contents for 15 lakes and reservoirs; watet quality for 21 streams. Also included are crest-stage partial-record stations, 3 miscellaneous measurement sites, and 5 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

Brain size and white matter content of cerebrospinal tracts determine the upper cervical cord area: evidence from structural brain MRI

Energy Technology Data Exchange (ETDEWEB)

Engl, Christina; Arsic, Milan; Boucard, Christine C.; Biberacher, Viola; Nunnemann, Sabine; Muehlau, Mark [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Technische Universitaet Muenchen, TUM-Neuroimaging Center, Klinikum rechts der Isar, Munich (Germany); Schmidt, Paul [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Ludwig-Maximilians-University Muenchen, Department of Statistics, Munich (Germany); Roettinger, Michael [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Muenchner Institut fuer Neuroradiologie, Munich (Germany); Etgen, Thorleif [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Klinikum Traunstein, Department of Neurology, Traunstein (Germany); Koutsouleris, Nikolaos; Meisenzahl, Eva M. [Ludwig-Maximilians-Universitaet Muenchen, Department of Psychiatry and Psychotherapy, Munich (Germany); Reiser, Maximilian [Ludwig-Maximilians-Universitaet, Department of Radiology, Munich (Germany)

2013-08-15

Measurement of the upper cervical cord area (UCCA) from brain MRI may be an effective way to quantify spinal cord involvement in neurological disorders such as multiple sclerosis. However, knowledge on the determinants of UCCA in healthy controls (HCs) is limited. In two cohorts of 133 and 285 HCs, we studied the influence of different demographic, body-related, and brain-related parameters on UCCA by simple and partial correlation analyses as well as by voxel-based morphometry (VBM) across both cerebral gray matter (GM) and white matter (WM). First, we confirmed the known but moderate effect of age on UCCA in the older cohort. Second, we studied the correlation of UCCA with sex, body height, and total intracranial volume (TIV). TIV was the only variable that correlated significantly with UCCA after correction for the other variables. Third, we studied the correlation of UCCA with brain-related parameters. Brain volume correlated stronger with UCCA than TIV. Both volumes of the brain tissue compartments GM and WM correlated with UCCA significantly. WM volume explained variance of UCCA after correction for GM volume, whilst the opposite was not observed. Correspondingly, VBM did not yield any brain region, whose GM content correlated significantly with UCCA, whilst cerebral WM content of cerebrospinal tracts strongly correlated with UCCA. This latter effect increased along a craniocaudal gradient. UCCA is mainly determined by brain volume as well as by WM content of cerebrospinal tracts. (orig.)

Thermodynamic interrelation between excess limiting partial molar characteristics of a liquid nonelectrolyte

International Nuclear Information System (INIS)

Ivanov, Evgeniy V.

2012-01-01

Highlights: ► Excess limiting molar volume may be regarded as a solvation-related characteristic. ► Volumetric and enthalpic effects of dissolution are interrelated thermodynamically. ► Possibility to estimate the partial change in solute compressibility is described. - Abstract: On the basis of thermodynamic analysis, it is concluded that the excess limiting partial molar volume, like the excess limiting partial molar enthalpy, can be considered as a solvation-related characteristic of a liquid nonelectrolyte. A thermodynamically grounded interrelation between standard volumetric and enthalpic effects of solution of a liquid nonelectrolyte (or series of nonelectrolytes) is suggested.

Apparent and partial molar volumes of long-chain alkyldimethylbenzylammonium chlorides and bromides in aqueous solutions at T=15 deg. C and T=25 deg. C

International Nuclear Information System (INIS)

Gonzalez-Perez, A.; Ruso, J.M.; Nimo, J.; Rodriguez, J.R.

2003-01-01

Density measurements of dodecyl- (C 12 DBACl), tetradecyl- (C 14 DBACl), hexadecyldimethylbenzylammonium chloride (C 16 DBACl) and of decyl- (C 10 DBABr) and dodecyldimethylbenzylammonium bromide (C 12 DBABr) in aqueous solutions at T=15 deg. C and T=25 deg. C have been carried out. From these results, apparent and partial molar volumes were calculated. Positive deviations from the Debye-Hueckel limiting law provide evidence for limited association at concentrations below the critical micelle concentration. The change of the apparent molar volume upon micellization was calculated. The relevant parameters have been presented in function of the alkyl chain length. Apparent molar volumes of the present compounds in the micellar phase, V phi m , and the change upon micellization, ΔV phi m , have been discussed in terms of temperature and type of counterion

Partial drying accelerates bacterial growth recovery to rewetting

DEFF Research Database (Denmark)

Meisner, Annelein; Leizeaga, Ainara; Rousk, Johannes

2017-01-01

, bacterial growth rates increase immediately in a linear fashion. In the Type 2 pattern, bacterial growth rates increase exponentially after a lag period. However, soils are often only partially dried. Partial drying (higher remaining moisture content before rewetting) may be considered a less harsh...

Buoyancy Effect of Ionic Vacancy on the Change of the Partial Molar Volume in Ferricyanide-Ferrocyanide Redox Reaction under a Vertical Gravity Field

Directory of Open Access Journals (Sweden)

Yoshinobu Oshikiri

2013-01-01

Full Text Available With a gravity electrode (GE in a vertical gravity field, the buoyancy effect of ionic vacancy on the change of the partial molar volume in the redox reaction between ferricyanide (FERRI and ferrocyanide (FERRO ions was examined. The buoyancy force of ionic vacancy takes a positive or negative value, depending on whether the rate-determining step is the production or extinction of the vacancy. Though the upward convection over an upward electrode in the FERRO ion oxidation suggests the contribution of the positive buoyancy force arising from the vacancy production, the partial molar volume of the vacancy was not measured. On the other hand, for the downward convection under a downward electrode in the FERRI ion reduction, it was not completely but partly measured by the contribution of the negative buoyancy force from the vacancy extinction. Since the lifetime of the vacancy is decreased by the collision between ionic vacancies during the convection, the former result was ascribed to the shortened lifetime due to the increasing collision efficiency in the enhanced upward convection over an upward electrode, whereas the latter was thought to arise from the elongated lifetime due to the decreasing collision efficiency by the stagnation under the downward electrode.

Establishment of an open database of realistic simulated data for evaluation of partial volume correction techniques in brain PET/MR

Energy Technology Data Exchange (ETDEWEB)

Mota, Ana [Instituto de Biofísica e Engenharia Biomédica, FC-UL, Lisboa (Portugal); Institute of Nuclear Medicine, UCL, London (United Kingdom); Cuplov, Vesna [Instituto de Biofísica e Engenharia Biomédica, FC-UL, Lisboa (Portugal); Schott, Jonathan; Hutton, Brian; Thielemans, Kris [Institute of Nuclear Medicine, UCL, London (United Kingdom); Drobnjak, Ivana [Centre of Medical Image Computing, UCL, London (United Kingdom); Dickson, John [Institute of Nuclear Medicine, UCL, London (United Kingdom); Bert, Julien [INSERM UMR1101, LaTIM, CHRU de Brest, Brest (France); Burgos, Ninon; Cardoso, Jorge; Modat, Marc; Ourselin, Sebastien [Centre of Medical Image Computing, UCL, London (United Kingdom); Erlandsson, Kjell [Institute of Nuclear Medicine, UCL, London (United Kingdom)

2015-05-18

The Partial Volume (PV) effect in Positron Emission Tomography (PET) imaging leads to loss in quantification accuracy, which manifests in PV effects (small objects occupy partially the sensitive volume of the imaging instrument, resulting in blurred images). Simultaneous acquisition of PET and Magnetic Resonance Imaging (MRI) produces concurrent metabolic and anatomical information. The latter has proved to be very helpful for the correction of PV effects. Currently, there are several techniques used for PV correction. They can be applied directly during the reconstruction process or as a post-processing step after image reconstruction. In order to evaluate the efficacy of the different PV correction techniques in brain- PET, we are constructing a database of simulated data. Here we present the framework and steps involved in constructing this database. Static 18F-FDG epilepsy and 18F-Florbetapir amyloid dementia PET/MR were selected because of their very different characteristics. The methodology followed was based on four main steps: Image pre-processing, Ground Truth (GT) generation, MRI and PET data simulation and reconstruction. All steps used Open Source software and can therefore be repeated at any centre. The framework as well as the database will be freely accessible. Tools used included GIF, FSL, POSSUM, GATE and STIR. The final data obtained after simulation, involving raw or reconstructed PET data together with corresponding MRI datasets, were close to the original patient data. Besides, there is the advantage that data can be compared with the GT. We indicate several parameters that can be improved and optimized.

Establishment of an open database of realistic simulated data for evaluation of partial volume correction techniques in brain PET/MR

International Nuclear Information System (INIS)

Mota, Ana; Cuplov, Vesna; Schott, Jonathan; Hutton, Brian; Thielemans, Kris; Drobnjak, Ivana; Dickson, John; Bert, Julien; Burgos, Ninon; Cardoso, Jorge; Modat, Marc; Ourselin, Sebastien; Erlandsson, Kjell

2015-01-01

The Partial Volume (PV) effect in Positron Emission Tomography (PET) imaging leads to loss in quantification accuracy, which manifests in PV effects (small objects occupy partially the sensitive volume of the imaging instrument, resulting in blurred images). Simultaneous acquisition of PET and Magnetic Resonance Imaging (MRI) produces concurrent metabolic and anatomical information. The latter has proved to be very helpful for the correction of PV effects. Currently, there are several techniques used for PV correction. They can be applied directly during the reconstruction process or as a post-processing step after image reconstruction. In order to evaluate the efficacy of the different PV correction techniques in brain- PET, we are constructing a database of simulated data. Here we present the framework and steps involved in constructing this database. Static 18F-FDG epilepsy and 18F-Florbetapir amyloid dementia PET/MR were selected because of their very different characteristics. The methodology followed was based on four main steps: Image pre-processing, Ground Truth (GT) generation, MRI and PET data simulation and reconstruction. All steps used Open Source software and can therefore be repeated at any centre. The framework as well as the database will be freely accessible. Tools used included GIF, FSL, POSSUM, GATE and STIR. The final data obtained after simulation, involving raw or reconstructed PET data together with corresponding MRI datasets, were close to the original patient data. Besides, there is the advantage that data can be compared with the GT. We indicate several parameters that can be improved and optimized.

Atomic disintegrations for partially hyperbolic diffeomorphisms

NARCIS (Netherlands)

Homburg, Ale Jan

2017-01-01

Shub and Wilkinson and Ruelle and Wilkinson studied a class of volume preserving diffeomorphisms on the three dimensional torus that are stably ergodic. The diffeomorphisms are partially hyperbolic and admit an invariant central foliation of circles. The foliation is not absolutely continuous; in

The theory and measurement of partial discharge transients

DEFF Research Database (Denmark)

Pedersen, Aage; Crichton, George C; McAllister, Iain Wilson

1991-01-01

A theoretical approach to partial discharge transients is presented. This approach is based on the relationship between the charge induced on the measurement electrode by those created in the interelectrode volume during partial discharge activity. The primary sources for these induced charges ar...... electrode systems of practical interest is illustrated. A discussion of the salient features and practical aspects of the theory is included...

Estimation of vapour pressure and partial pressure of subliming ...

Indian Academy of Sciences (India)

Administrator

conditions of (total) pressure by using thermogravimetry under those conditions. Further, from the partial pressure P, it is possible to determine the number of moles of material in the vapour phase using the ideal gas equation, PV = nRT, where P is the partial pressure, V the volume, n number of moles (of the vapour), R the ...

Partial molar volume of paracetamol in water, 0.1 M HCl and 0.154 M NaCl at T = (298.15, 303.15, 308.15 and 310.65) K and at 101.325 kPa

Energy Technology Data Exchange (ETDEWEB)

Iqbal, Muhammad Javed [Department of Chemistry, Quaid-i-Azam University, Islamabad, Capital 54320 (Pakistan)]. E-mail: mjiqauchem@yahoo.com; Malik, Qaisar Mahmood [Department of Chemistry, Quaid-i-Azam University, Islamabad, Capital 54320 (Pakistan)]. E-mail: qaisar_@hotmail.com

2005-12-15

The apparent molar volume of paracetamol (4-acetamidophenol) in water, 0.1 M HCl and 0.154 M NaCl as solvents at (298.15, 303.15, 308.15 and 310.65) K temperatures and at a pressure of 101.325 kPa were determined from the density data obtained with the help of a vibrating-tube Anton Paar DMA-48 densimeter. The partial molar volume, V {sub m}, of paracetamol in these solvents at different temperatures was evaluated by extrapolating the apparent molar volume versus molality plots to m = 0. In addition, the partial molar expansivity, E {sup .}, the isobaric coefficient of thermal expansion, {alpha} {sub p}, and the interaction coefficient, S {sub v}, have also been computed. The expansivity data show dependence of E {sup .} values on the structure of the solute molecules.

Partial molar volume of paracetamol in water, 0.1 M HCl and 0.154 M NaCl at T = (298.15, 303.15, 308.15 and 310.65) K and at 101.325 kPa

International Nuclear Information System (INIS)

Iqbal, Muhammad Javed; Malik, Qaisar Mahmood

2005-01-01

The apparent molar volume of paracetamol (4-acetamidophenol) in water, 0.1 M HCl and 0.154 M NaCl as solvents at (298.15, 303.15, 308.15 and 310.65) K temperatures and at a pressure of 101.325 kPa were determined from the density data obtained with the help of a vibrating-tube Anton Paar DMA-48 densimeter. The partial molar volume, V m , of paracetamol in these solvents at different temperatures was evaluated by extrapolating the apparent molar volume versus molality plots to m = 0. In addition, the partial molar expansivity, E . , the isobaric coefficient of thermal expansion, α p , and the interaction coefficient, S v , have also been computed. The expansivity data show dependence of E . values on the structure of the solute molecules

Water Resources Data--California, Water Year 2002, Volume 1, Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

Science.gov (United States)

Rockwell, G.L.; Pope, G.L.; Agajanian, J.; Caldwell, L.A.

2003-01-01

Water-resources data for the 2002 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 188 gaging stations and 10 crest-stage partial-record stations, stage and contents for 19 lakes and reservoirs, gage-height records for 2 stations, water quality for 39 streamflow-gaging stations and 11 partial-record stations, and precipitation data for 1 station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

Water Resources Data -- California, Water Year 2003, Volume 1, Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

Science.gov (United States)

Pope, G.L.; Agajanian, J.; Caldwell, L.A.; Rockwell, G.L.

2004-01-01

Water-resources data for the 2003 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 193 gaging stations and 11 crest-stage partial-record stations, stage and contents for 22 lakes and reservoirs, gage-height records for 2 stations, water quality for 47 streamflow-gaging stations and 12 partial-record stations, and precipitation data for 1 station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

Water resources data, California, water year 2004, volume 1: Southern Great Basin from Mexican border to Mono Lake Basin, and Pacific Slope basins from Tijuana River to Santa Maria River

Science.gov (United States)

Agajanian, J.; Caldwell, L.A.; Rockwell, G.L.; Pope, G.L.

2005-01-01

Water-resources data for the 2004 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 195 gaging stations and 10 crest-stage partial-record stations, stage and contents for 25 lakes and reservoirs, gage-height records for 2 stations, water quality for 47 streamflow-gaging stations and 7 partial-record stations, and precipitation data for 5 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

Non-destructive and rapid prediction of moisture content in red pepper (Capsicum annuum L.) powder using near-infrared spectroscopy and a partial least squares regression model

Science.gov (United States)

Purpose: The aim of this study was to develop a technique for the non-destructive and rapid prediction of the moisture content in red pepper powder using near-infrared (NIR) spectroscopy and a partial least squares regression (PLSR) model. Methods: Three red pepper powder products were separated in...

Differences in the behaviour of HTO and H2O in soil after condensation from the atmosphere and conversion of HT to HTO and OBT in soil relative to moisture content and pore volume

International Nuclear Information System (INIS)

Bunnenberg, C.; Feinhals, J.; Wiener, B.

1986-01-01

Theoretical considerations and field and soil column experiments have identified the condensation of atmospheric water vapour as an additional process in the HTO contamination of soils. In contrast to wash-out, where tritium concentrations of the deposited water are the same as in the falling drops, the specific activity of the condensed water is increased compared with that of the atmospheric humidity, when the partial vapour pressure gradient of HTO between atmosphere and soil is higher than the H 2 O pressure gradient. With respect to HTO deposition, condensation may therefore be more effective per unit precipitation than wash-out. Experiments on the conversion rates of HT to HTO and OBT in soils have exhibited a pronounced dependence on moisture content and free pore volume. With rising moisture content, conversion increases due to enhanced bacterial action; while close to field capacity a decrease occurs as a result of restricted HT diffusion through the soil pores. In short-term experiments about 0.1% of the converted HT was found in the OBT form. (author)

Effect of tidal volume on extravascular lung water content during one-lung ventilation for video-assisted thoracoscopic surgery: a randomised, controlled trial.

Science.gov (United States)

Qutub, Hatem; El-Tahan, Mohamed R; Mowafi, Hany A; El Ghoneimy, Yasser F; Regal, Mohamed A; Al Saflan, AbdulHadi A

2014-09-01

The use of low tidal volume during one-lung ventilation (OLV) has been shown to attenuate the incidence of acute lung injury after thoracic surgery. To test the effect of tidal volume during OLV for video-assisted thoracoscopic surgery on the extravascular lung water content index (EVLWI). A randomised, double-blind, controlled study. Single university hospital. Thirty-nine patients scheduled for elective video-assisted thoracoscopic surgery. Patients were randomly assigned to one of three groups (n = 13 per group) to ventilate the dependent lung with a tidal volume of 4, 6 or 8 ml  kg(-1) predicted body weight with I:E ratio of 1:2.5 and PEEP of 5 cm H2O. The primary outcomes were perioperative changes in EVLWI and EVLWI to intrathoracic blood volume index (ITBVI) ratio. Secondary outcomes included haemodynamics, oxygenation indices, incidences of postoperative acute lung injury, atelectasis, pneumonia, morbidity and 30-day mortality. A tidal volume of 4 compared with 6 and 8 ml  kg(-1) after 45 min of OLV resulted in an EVLWI of 4.1 [95% confidence interval (CI) 3.5 to 4.7] compared with 7.7 (95% CI 6.7 to 8.6) and 8.6 (95% CI 7.5 to 9.7) ml  kg(-1), respectively (P tidal volume of 4 ml kg during OLV was associated with less lung water content than with larger tidal volumes of 6 to 8 ml kg(-1), although no patient developed acute lung injury. Further studies are required to address the usefulness of EVLWI as a marker for the development of postoperative acute lung injury after the use of a low tidal volume during OLV in patients undergoing pulmonary resection. Clinicaltrials.gov identifier: NCT01762709.

Coupling model of aerobic waste degradation considering temperature, initial moisture content and air injection volume.

Science.gov (United States)

Ma, Jun; Liu, Lei; Ge, Sai; Xue, Qiang; Li, Jiangshan; Wan, Yong; Hui, Xinminnan

2018-03-01

A quantitative description of aerobic waste degradation is important in evaluating landfill waste stability and economic management. This research aimed to develop a coupling model to predict the degree of aerobic waste degradation. On the basis of the first-order kinetic equation and the law of conservation of mass, we first developed the coupling model of aerobic waste degradation that considered temperature, initial moisture content and air injection volume to simulate and predict the chemical oxygen demand in the leachate. Three different laboratory experiments on aerobic waste degradation were simulated to test the model applicability. Parameter sensitivity analyses were conducted to evaluate the reliability of parameters. The coupling model can simulate aerobic waste degradation, and the obtained simulation agreed with the corresponding results of the experiment. Comparison of the experiment and simulation demonstrated that the coupling model is a new approach to predict aerobic waste degradation and can be considered as the basis for selecting the economic air injection volume and appropriate management in the future.

Stochastic partial differential equations an introduction

CERN Document Server

Liu, Wei

2015-01-01

This book provides an introduction to the theory of stochastic partial differential equations (SPDEs) of evolutionary type. SPDEs are one of the main research directions in probability theory with several wide ranging applications. Many types of dynamics with stochastic influence in nature or man-made complex systems can be modelled by such equations. The theory of SPDEs is based both on the theory of deterministic partial differential equations, as well as on modern stochastic analysis. Whilst this volume mainly follows the ‘variational approach’, it also contains a short account on the ‘semigroup (or mild solution) approach’. In particular, the volume contains a complete presentation of the main existence and uniqueness results in the case of locally monotone coefficients. Various types of generalized coercivity conditions are shown to guarantee non-explosion, but also a systematic approach to treat SPDEs with explosion in finite time is developed. It is, so far, the only book where the latter and t...

How broadcast volume and emotional content affect youth recall of anti-tobacco advertising.

Science.gov (United States)

Biener, Lois; Wakefield, Melanie; Shiner, Cecilia M; Siegel, Michael

2008-07-01

Televised anti-tobacco advertising has been shown to be effective for discouraging smoking initiation; however, purchasing broadcasting time is very costly. This study investigated the relative impact of the broadcast volume (media weight) and the emotional content of an ad as predictors of advertising recall. The data come from a random-digit-dialed survey conducted in 2001 and 2002 of 3863 youth aged 12-17. Media weight was based on commercial TV ratings data. The emotional intensity of advertisements was derived from the ratings made by independent youth judges. Data analyses were conducted between 2005 and 2007. Results indicated that media weight was a significant predictor of recall, but the emotional content of the ad was an even stronger predictor. Also, ads low in emotional intensity required more media weight than those high in emotional intensity to achieve the same amount of increase in recall. This study extends prior research that highlights the importance of emotional intensity for effective anti-tobacco advertising. It also indicates that, relative to unemotional advertisements, emotionally arousing advertisements require fewer broadcasts to achieve the same level of recall, and hence are likely to be less costly to a public health campaign.

Water Resources Data for California, Water Year 1988. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

Science.gov (United States)

Polinoski, K.G.; Hoffman, E.B.; Smith, G.B.; Bowers, J.C.

1989-01-01

Water resources data for the 1988 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 134 gaging stations; stage and contents for 17 lakes and reservoirs; and water quality for 24 streams. Also included are 10 crest-stage partial-record stations, 5 miscellaneous measurement sites, and 16 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

Water Resources Data for California, Water Year 1987. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

Science.gov (United States)

Bowers, J.C.; McConaughy, C.E.; Polinoski, K.G.; Smith, G.B.

1988-01-01

Water resources data for the 1987 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 134 gaging stations; stage and contents for 16 lakes and reservoirs; and water quality for 16 streams. Also included are 10 crest-stage partial-record stations, 3 miscellaneous measurement sites, and 10 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET

DEFF Research Database (Denmark)

IIda, H.; Law, I.; Pakkenberg, B.

2000-01-01

Limited spatial resolution of positron emission tomography (PET) can cause significant underestimation in the observed regional radioactivity concentration (so-called partial volume effect or PVE) resulting in systematic errors in estimating quantitative physiologic parameters. The authors have...... formulated four mathematical models that describe the dynamic behavior of a freely diffusible tracer (H215O) in a region of interest (ROI) incorporating estimates of regional tissue flow that are independent of PVE. The current study was intended to evaluate the feasibility of these models and to establish...... a methodology to accurately quantify regional cerebral blood flow (CBF) corrected for PVE in cortical gray matter regions. Five monkeys were studied with PET after IV H2(15)O two times (n = 3) or three times (n = 2) in a row. Two ROIs were drawn on structural magnetic resonance imaging (MRI) scans and projected...

Topics in numerical partial differential equations and scientific computing

CERN Document Server

2016-01-01

Numerical partial differential equations (PDEs) are an important part of numerical simulation, the third component of the modern methodology for science and engineering, besides the traditional theory and experiment. This volume contains papers that originated with the collaborative research of the teams that participated in the IMA Workshop for Women in Applied Mathematics: Numerical Partial Differential Equations and Scientific Computing in August 2014.

A comparison of five partial volume correction methods for Tau and Amyloid PET imaging with [18F]THK5351 and [11C]PIB.

Science.gov (United States)

Shidahara, Miho; Thomas, Benjamin A; Okamura, Nobuyuki; Ibaraki, Masanobu; Matsubara, Keisuke; Oyama, Senri; Ishikawa, Yoichi; Watanuki, Shoichi; Iwata, Ren; Furumoto, Shozo; Tashiro, Manabu; Yanai, Kazuhiko; Gonda, Kohsuke; Watabe, Hiroshi

2017-08-01

To suppress partial volume effect (PVE) in brain PET, there have been many algorithms proposed. However, each methodology has different property due to its assumption and algorithms. Our aim of this study was to investigate the difference among partial volume correction (PVC) method for tau and amyloid PET study. We investigated two of the most commonly used PVC methods, Müller-Gärtner (MG) and geometric transfer matrix (GTM) and also other three methods for clinical tau and amyloid PET imaging. One healthy control (HC) and one Alzheimer's disease (AD) PET studies of both [ 18 F]THK5351 and [ 11 C]PIB were performed using a Eminence STARGATE scanner (Shimadzu Inc., Kyoto, Japan). All PET images were corrected for PVE by MG, GTM, Labbé (LABBE), Regional voxel-based (RBV), and Iterative Yang (IY) methods, with segmented or parcellated anatomical information processed by FreeSurfer, derived from individual MR images. PVC results of 5 algorithms were compared with the uncorrected data. In regions of high uptake of [ 18 F]THK5351 and [ 11 C]PIB, different PVCs demonstrated different SUVRs. The degree of difference between PVE uncorrected and corrected depends on not only PVC algorithm but also type of tracer and subject condition. Presented PVC methods are straight-forward to implement but the corrected images require careful interpretation as different methods result in different levels of recovery.

Function spaces and partial differential equations volume 2 : contemporary analysis

CERN Document Server

Taheri, Ali

2015-01-01

This is a book written primarily for graduate students and early researchers in the fields of Analysis and Partial Differential Equations (PDEs). Coverage of the material is essentially self-contained, extensive and novel with great attention to details and rigour.

8th International Conference on Partial Least Squares and Related Methods

CERN Document Server

Vinzi, Vincenzo; Russolillo, Giorgio; Saporta, Gilbert; Trinchera, Laura

2016-01-01

This volume presents state of the art theories, new developments, and important applications of Partial Least Square (PLS) methods. The text begins with the invited communications of current leaders in the field who cover the history of PLS, an overview of methodological issues, and recent advances in regression and multi-block approaches. The rest of the volume comprises selected, reviewed contributions from the 8th International Conference on Partial Least Squares and Related Methods held in Paris, France, on 26-28 May, 2014. They are organized in four coherent sections: 1) new developments in genomics and brain imaging, 2) new and alternative methods for multi-table and path analysis, 3) advances in partial least square regression (PLSR), and 4) partial least square path modeling (PLS-PM) breakthroughs and applications. PLS methods are very versatile methods that are now used in areas as diverse as engineering, life science, sociology, psychology, brain imaging, genomics, and business among both academics ...

Lowering the alcohol content of red wine does not alter its cardioprotective properties.

Science.gov (United States)

Lamont, Kim; Blackhurst, Dee; Albertyn, Zulfah; Marais, David; Lecour, Sandrine

2012-05-23

Many epidemiological, clinical and laboratory studies suggest that chronic and moderate consumption of red wine benefits cardiovascular health, because of the alcoholic content or the polyphenols/flavonoids. The antioxidant and cardioprotective properties of a French red wine (cabernet sauvignon, 12% alcohol by volume) were compared with those of the same wine subjected to reverse osmosis for partial removal of alcohol (6% alcohol by volume). Antioxidant capacity was assessed in vitro using the oxygen radical absorbance capacity (ORAC) assay. To test the cardioprotective effect of 12% v. 6% wine, the drinking water of rats used for controls was supplemented with red wine (12% or 6%). After 10 days, hearts were isolated on a Langendorff system and subjected to 30 minutes of global ischaemia plus 30 minutes of reperfusion (I/R). No differences in antioxidant capacity were observed between wine of 12% and 6% alcohol content (n=8 per group). Control hearts subjected to I/R presented a rate pressure product (heart rate x left ventricular developed pressure, expressed as a percentage of baseline value) of 16±4% (mean±standard error). Pretreatment with wine 12% or 6% improved the rate pressure product to 40±6% and 43±6%, respectively (pwine did not alter its antioxidant and cardioprotective properties. Moderate and regular consumption of lower alcohol content wines may confer beneficial effects without the risks associated with traditional wines of higher alcohol content.

Apparent and standard partial molar heat capacities and volumes of aqueous tartaric acid and its sodium salts at elevated temperature and pressure

International Nuclear Information System (INIS)

Xie Wei; Trevani, Liliana; Tremaine, Peter R.

2004-01-01

Apparent molar heat capacities and volumes have been determined for aqueous solutions of tartaric acid (H 2 Tar, Tar=C 4 H 4 O 6 ), two buffer solutions of (H 2 Tar/NaHTar) and (NaHTar/Na 2 Tar), and solutions of disodium tartrate (Na 2 Tar) at four temperatures in the range 283.15≤T/K≤328.15 at p=1 MPa. Apparent molar volumes for H 2 Tar(aq) and Na 2 Tar(aq) have been measured at temperatures 377.15≤T/K≤529.15 and p=10.4 MPa. The experimental results have been represented with a model to describe the molality and temperature dependence. Extrapolations to infinite dilution yielded standard partial molar heat capacities C p 0 and volumes V 0 for the species H 2 Tar(aq), HTar - (aq) and Tar 2- (aq) over the range of experimental measurements. The temperature dependence of V 0 for Na 2 Tar(aq) is consistent with other aqueous electrolytes, while that of H 2 Tar(aq) may be anomalous, in that it does not show divergence towards increasingly positive values with increasing temperature

An analysis of the nucleon spectrum from lattice partially-quenched QCD

Energy Technology Data Exchange (ETDEWEB)

Armour, W. [Swansea University, Swansea, SA2 8PP, Wales, U.K.; Allton, C. R. [Swansea University, Swansea, SA2 8PP, Wales, U.K.; Leinweber, Derek B. [Univ. of Adelaide, SA (Australia); Thomas, Anthony W. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); College of William and Mary, Williamsburg, VA (United States); Young, Ross D. [Argonne National Lab. (ANL), Argonne, IL (United States)

2010-09-01

The chiral extrapolation of the nucleon mass, Mn, is investigated using data coming from 2-flavour partially-quenched lattice simulations. The leading one-loop corrections to the nucleon mass are derived for partially-quenched QCD. A large sample of lattice results from the CP-PACS Collaboration is analysed, with explicit corrections for finite lattice spacing artifacts. The extrapolation is studied using finite range regularised chiral perturbation theory. The analysis also provides a quantitative estimate of the leading finite volume corrections. It is found that the discretisation, finite-volume and partial quenching effects can all be very well described in this framework, producing an extrapolated value of Mn in agreement with experiment. This procedure is also compared with extrapolations based on polynomial forms, where the results are less encouraging.

Maintenance Personnel Performance Simulation (MAPPS) model: description of model content, structure, and sensitivity testing. Volume 2

International Nuclear Information System (INIS)

Siegel, A.I.; Bartter, W.D.; Wolf, J.J.; Knee, H.E.

1984-12-01

This volume of NUREG/CR-3626 presents details of the content, structure, and sensitivity testing of the Maintenance Personnel Performance Simulation (MAPPS) model that was described in summary in volume one of this report. The MAPPS model is a generalized stochastic computer simulation model developed to simulate the performance of maintenance personnel in nuclear power plants. The MAPPS model considers workplace, maintenance technician, motivation, human factors, and task oriented variables to yield predictive information about the effects of these variables on successful maintenance task performance. All major model variables are discussed in detail and their implementation and interactive effects are outlined. The model was examined for disqualifying defects from a number of viewpoints, including sensitivity testing. This examination led to the identification of some minor recalibration efforts which were carried out. These positive results indicate that MAPPS is ready for initial and controlled applications which are in conformity with its purposes

Partial volume effect correction in PET using regularized iterative deconvolution with variance control based on local topology

International Nuclear Information System (INIS)

Kirov, A S; Schmidtlein, C R; Piao, J Z

2008-01-01

Correcting positron emission tomography (PET) images for the partial volume effect (PVE) due to the limited resolution of PET has been a long-standing challenge. Various approaches including incorporation of the system response function in the reconstruction have been previously tested. We present a post-reconstruction PVE correction based on iterative deconvolution using a 3D maximum likelihood expectation-maximization (MLEM) algorithm. To achieve convergence we used a one step late (OSL) regularization procedure based on the assumption of local monotonic behavior of the PET signal following Alenius et al. This technique was further modified to selectively control variance depending on the local topology of the PET image. No prior 'anatomic' information is needed in this approach. An estimate of the noise properties of the image is used instead. The procedure was tested for symmetric and isotropic deconvolution functions with Gaussian shape and full width at half-maximum (FWHM) ranging from 6.31 mm to infinity. The method was applied to simulated and experimental scans of the NEMA NU 2 image quality phantom with the GE Discovery LS PET/CT scanner. The phantom contained uniform activity spheres with diameters ranging from 1 cm to 3.7 cm within uniform background. The optimal sphere activity to variance ratio was obtained when the deconvolution function was replaced by a step function few voxels wide. In this case, the deconvolution method converged in ∼3-5 iterations for most points on both the simulated and experimental images. For the 1 cm diameter sphere, the contrast recovery improved from 12% to 36% in the simulated and from 21% to 55% in the experimental data. Recovery coefficients between 80% and 120% were obtained for all larger spheres, except for the 13 mm diameter sphere in the simulated scan (68%). No increase in variance was observed except for a few voxels neighboring strong activity gradients and inside the largest spheres. Testing the method for

Numerical Investigation on Absorption Enhancement of Black Carbon Aerosols Partially Coated With Nonabsorbing Organics

Science.gov (United States)

Zhang, Xiaolin; Mao, Mao; Yin, Yan; Wang, Bin

2018-01-01

This study numerically evaluates the effects of aerosol microphysics, including coated volume fraction of black carbon (BC), shell/core ratio, and size distribution, on the absorption enhancement (Eab) of polydisperse BC aggregates partially coated by organics, which is calculated by the exact multiple-sphere T-matrix method. The coated volume fraction of BC plays a substantial role in determining the absorption enhancement of partially coated BC aggregates, which typically have an Eab in the range of 1.0-2.0 with a larger value for larger coated volume fraction of BC as the shell/core ratio, BC geometry, and size distribution are fixed. The shell/core ratio, BC geometry, and size distribution have little impact on the Eab of coated BC with small coated volume fraction of BC, while they become significant for large coated volume fraction of BC. The Eab of partially coated BC particles can be slightly less than 1.0 for the large BC in the accumulation mode exhibiting large shell/core ratio and small coated volume fraction of BC, indicating that the absorption shows even slight decrease relative to uncoated BC particles. For partially coated BC aggregates in the accumulation and coarse modes, the refractive index uncertainties of BC result in the Eab differences of less than 9% and 2%, respectively, while those of organics can induce larger variations with the maximum differences up to 22% and 18%, respectively. Our study indicates that accounting for particle coating microphysics, particularly the coated volume fraction of BC, can potentially help to understand the differences in observations of largely variable absorption enhancements over various regions.

Scintigraphic determination of the spleen volume in case of partial splenectomy for a Minkowski-Chauffard disease. About 15 cases; Determination scintigraphique du volume splenique en cas de splenectomie partielle pour une maladie de Minkowski-Chauffard. A propos de 15 cas

Energy Technology Data Exchange (ETDEWEB)

Berehou, F.; Ben Rais, N. [CHU Ibn Sina, Rabat, Service de medecine nucleaire (Morocco); Calzada, M.; Keller, I.; Devaux, J. [Hopital Saint-Antoine, service de medecine nucleaire, 75 - Paris (France)

2010-07-01

Splenic scintigraphy with labeled and fragile red blood cells is a simple, reliable, noninvasive and low radiating method to assess at long-term residual splenic volume after partial splenectomy, it is the only treatment for a good quality of life with fewer infections, fewer transfusions and without use of lifelong vaccinations for a chronic illness. (N.C.)

Liver regeneration and restoration of liver function after partial hepatectomy in patients with liver tumors

International Nuclear Information System (INIS)

Jansen, P.L.M.; Chamuleau, R.A.F.; Leeuwen, D.J. van; Schippor, H.G.; Busemann-Sokole, E.; Heyde, M.N. van der

1990-01-01

Liver regeneration and restoration of liver function were studied in six patients who underwent partial hepatectomy with removal of 30-70% of the liver. Liver volume and liver regeneration were studied by single photon computed tomography (SPECT), using 99m Tc-colloid as tracer. The method was assessed in 11 patients by comparing the pre- and post-operative volume measurement with the volume of the resected liver mass. Liver function was determined by measuring the galactose elimination capacity and the caffeine clearance. After a postoperative follow-up period of 50 days, the liver had regenerated maximally to a volume of 75 ± 2% of the preoperative liver mass. Maximal restoration of liver function was achieved 120 days after operation and amounted to 75 ± 10% for the caffeine clearance and to 100 ± 25% for the galactose elimination capacity. This study shows that SPECT is a useful method for assessing liver regeneration in patients after partial hepatectomy. The study furthermore shows that caffeine clearance correlates well with total liver volume, whereas the galactose elimination capacity overestimates total liver volume after partial hepatectomy. 22 refs

Switching field of partially exchange-coupled particles

International Nuclear Information System (INIS)

Oliva, M.I.; Bertorello, H.R.; Bercoff, P.G.

2004-01-01

The magnetization reversal of partially exchange-coupled particles is studied in detail. The starting point is the observation of a complicated phenomenology in the irreversible susceptibility and FORC distribution functions of Ba hexaferrite samples obtained by means of different sintering conditions. Several peaks in the first-order reversal curve (FORC) distribution functions were identified and associated with clusters with different number of particles. The switching fields of these clusters were related to an effective anisotropy constant Keff that depends on the number of particles in the cluster. Keff is linked to the exchange-coupled volume between two neighboring particles and as a weighted mean between the anisotropy constants of the coupled and uncoupled volumes. By using the modified Brown's equation αex=0.322 is obtained.In order to interpret these results, the switching field of a two-particle system with partial exchange coupling is studied. It is assumed that the spins reorientation across the contact plane between the particles is like a Bloch wall. The energy of the system is written in terms of the fraction of volume affected by exchange coupling and the switching fields for both particles are calculated. At small interaction volume fraction each particle inverts its magnetization independently from the other. As the fraction of exchange-coupled volume increases, cooperative effects appear and the two particles invert their magnetization in a cooperative way.The proposed model allows to interpret for the first time the empirical factor αex in terms of physical arguments and also explain the details observed in the FORC distribution function

Defining the Role of Free Flaps in Partial Breast Reconstruction.

Science.gov (United States)

Smith, Mark L; Molina, Bianca J; Dayan, Erez; Jablonka, Eric M; Okwali, Michelle; Kim, Julie N; Dayan, Joseph H

2018-03-01

 Free flaps have a well-established role in breast reconstruction after mastectomy; however, their role in partial breast reconstruction remains poorly defined. We reviewed our experience with partial breast reconstruction to better understand indications for free tissue transfer.  A retrospective review was performed of all patients undergoing partial breast reconstruction at our center between February 2009 and October 2015. We evaluated the characteristics of patients who underwent volume displacement procedures versus volume replacement procedures and free versus pedicled flap reconstruction.  There were 78 partial breast reconstructions, with 52 reductions/tissue rearrangements (displacement group) and 26 flaps (replacement group). Bra cup size and body mass index (BMI) were significantly smaller in the replacement group. Fifteen pedicled and 11 free flaps were performed. Most pedicled flaps (80.0%) were used for lateral or upper pole defects. Most free flaps (72.7%) were used for medial and inferior defects or when there was inadequate donor tissue for a pedicled flap. Complications included hematoma, cellulitis, and one aborted pedicled flap.  Free and pedicled flaps are useful for partial breast reconstruction, particularly in breast cancer patients with small breasts undergoing breast-conserving treatment (BCT). Flap selection depends on defect size, location, and donor tissue availability. Medial defects are difficult to reconstruct using pedicled flaps due to arc of rotation and intervening breast tissue. Free tissue transfer can overcome these obstacles. Confirming negative margins before flap reconstruction ensures harvest of adequate volume and avoids later re-operation. Judicious use of free flaps for oncoplastic reconstruction expands the possibility for breast conservation. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Cerebral blood flow in temporal lobe epilepsy: a partial volume correction study

Energy Technology Data Exchange (ETDEWEB)

Giovacchini, Giampiero [University Milano-Bicocca, Milan (Italy); Bonwetsch, Robert; Theodore, William H. [National Institute of Neurological Diseases and Strokes, Clinical Epilepsy Section, Bethesda, MD (United States); Herscovitch, Peter [National Institutes of Health, PET Department, Clinical Center, Bethesda, MD (United States); Carson, Richard E. [Yale PET Center, New Haven, CT (United States)

2007-12-15

Previous studies in temporal lobe epilepsy (TLE) have shown that, owing to brain atrophy, positron emission tomography (PET) can overestimate deficits in measures of cerebral function such as glucose metabolism (CMR{sub glu}) and neuroreceptor binding. The magnitude of this effect on cerebral blood flow (CBF) is unexplored. The aim of this study was to assess CBF deficits in TLE before and after magnetic resonance imaging-based partial volume correction (PVC). Absolute values of CBF for 21 TLE patients and nine controls were computed before and after PVC. In TLE patients, quantitative CMR{sub glu} measurements also were obtained. Before PVC, regional values of CBF were significantly (p<0.05) lower in TLE patients than in controls in all regions, except the fusiform gyrus contralateral to the epileptic focus. After PVC, statistical significance was maintained in only four regions: ipsilateral inferior temporal cortex, bilateral insula and contralateral amygdala. There was no significant difference between patients and controls in CBF asymmetry indices (AIs) in any region before or after PVC. In TLE patients, AIs for CBF were significantly smaller than for CMR{sub glu} in middle and inferior temporal cortex, fusiform gyrus and hippocampus both before and after PVC. A significant positive relationship between disease duration and AIs for CMR{sub glu}, but not CBF, was detected in hippocampus and amygdala, before but not after PVC. PVC should be used for PET CBF measurements in patients with TLE. Reduced blood flow, in contrast to glucose metabolism, is mainly due to structural changes. (orig.)

Correlation between the 2-Dimensional Extent of Orbital Defects and the 3-Dimensional Volume of Herniated Orbital Content in Patients with Isolated Orbital Wall Fractures

Directory of Open Access Journals (Sweden)

Jong Hyun Cha

2017-01-01

Full Text Available BackgroundThe purpose of this study was to assess the correlation between the 2-dimensional (2D extent of orbital defects and the 3-dimensional (3D volume of herniated orbital content in patients with an orbital wall fracture.MethodsThis retrospective study was based on the medical records and radiologic data of 60 patients from January 2014 to June 2016 for a unilateral isolated orbital wall fracture. They were classified into 2 groups depending on whether the fracture involved the inferior wall (group I, n=30 or the medial wall (group M, n=30. The 2D area of the orbital defect was calculated using the conventional formula. The 2D extent of the orbital defect and the 3D volume of herniated orbital content were measured with 3D image processing software. Statistical analysis was performed to evaluate the correlations between the 2D and 3D parameters.ResultsVarying degrees of positive correlation were found between the 2D extent of the orbital defects and the 3D herniated orbital volume in both groups (Pearson correlation coefficient, 0.568−0.788; R2=32.2%−62.1%.ConclusionsBoth the calculated and measured 2D extent of the orbital defects showed a positive correlation with the 3D herniated orbital volume in orbital wall fractures. However, a relatively large volume of herniation (>0.9 cm3 occurred not infrequently despite the presence of a small orbital defect (<1.9 cm2. Therefore, estimating the 3D volume of the herniated content in addition to the 2D orbital defect would be helpful for determining whether surgery is indicated and ensuring adequate surgical outcomes.

Partial thyroid arterial embolization for the treatment of hyperthyroidism

International Nuclear Information System (INIS)

Brzozowski, Krzysztof; Piasecki, Piotr; Zięcina, Piotr; Frankowska, Emilia; Jaroszuk, Andrzej; Kamiński, Grzegorz; Bogusławska-Walecka, Romana

2012-01-01

Background: Hyperactive thyroid gland in patients that are unable to tolerate or accept standard therapy is a common clinical problem. Aim of the study was to evaluate effectiveness of partial thyroid arterial embolization in patients with hyperthyroidism. Material/methods: From May 2004 to November 2005 partial thyroid gland embolization was performed in 15 patients. Mean thyroid gland volume was 162 ml. Embolization of one to three thyriod arteries was performed with the mixture of Histoacryl and Lipiodol. Selective angiography was performed after embolization to ensure that the targeted arteries were completely occluded. Follow-up study covered 12 patients. Results: The embolization procedure was well tolerated by all patients. Three days after embolization fT3 and fT4 levels were higher than before the procedure. Further laboratory tests showed quick reversal to near-normal or normal levels of thyroid hormones. 12 weeks follow-up showed: normal serum levels of fT3, fT4 and TSH in 9 of 12 patients (75%), hyperthyroidism in 3 of 12 patients (25%), goiter volume reduction of approximately 32% of its original volume (from 13 to 76.3%), mean thyroid gland volume of 94 ml. One year after embolization 7 of 12 patients required thyreostatic drugs. At two and four years follow-up thyreostatics doses were significantly lower and thyroid tissue was fibrotic. Conclusions: Based on our results the treatment of the thyroid gland goiters using arterial thyroid gland partial embolization may be offered as an effective alternative for patients who will not or cannot accept standard therapy.

Partial gravity - Human impacts on facility design

Science.gov (United States)

Capps, Stephen; Moore, Nathan

1990-01-01

Partial gravity affects the body differently than earth gravity and microgravity environments. The main difference from earth gravity is human locomotion; while the main dfference from microgravity is the specific updown orientation and reach envelopes which increase volume requirements. Much data are available on earth gravity and microgravity design; however, very little information is available on human reactions to reduced gravity levels in IVA situations (without pressure suits). Therefore, if humans commit to permanent lunar habitation, much research should be conducted in the area of partial gravity effects on habitat design.

Partial differential equations

CERN Document Server

Sloan, D; Süli, E

2001-01-01

/homepage/sac/cam/na2000/index.html7-Volume Set now available at special set price ! Over the second half of the 20th century the subject area loosely referred to as numerical analysis of partial differential equations (PDEs) has undergone unprecedented development. At its practical end, the vigorous growth and steady diversification of the field were stimulated by the demand for accurate and reliable tools for computational modelling in physical sciences and engineering, and by the rapid development of computer hardware and architecture. At the more theoretical end, the analytical insight in

Water Resources Data. Ohio - Water Year 1992. Volume 1. Ohio River Basin excluding project data

Energy Technology Data Exchange (ETDEWEB)

H.L. Shindel; J.H. Klingler; J.P. Mangus; L.E. Trimble

1993-03-01

Water-resources data for the 1992 water year for Ohio consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, in two volumes, contains records for water discharge at 121 gaging stations, 336 wells, and 72 partial-record sites; and water levels at 312 observation wells. Also included are data from miscellaneous sites. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System collected by the US Geological Survey and cooperating State and Federal agencies in Ohio. Volume 1 covers the central and southern parts of Ohio, emphasizing the Ohio River Basin. (See Order Number DE95010451 for Volume 2 covering the northern part of Ohio.)

Evaluation of the reconstruction method and effect of partial volume in brain scintiscanning; Avaliacao do metodo de reconstrucao e efeito do volume parcial em cintilografia cerebral

Energy Technology Data Exchange (ETDEWEB)

Pinheiro, Monica Araujo

2016-10-01

Alzheimer's disease is a neurodegenerative disorder, on which occurs a progressive and irreversible destruction of neurons. According to the World Health Organization (WHO) 35.6 million people are living with dementia, being recommended that governments prioritize early diagnosis techniques. Laboratory and psychological tests for cognitive assessment are conducted and further complemented by neurological imaging from nuclear medicine exams in order to establish an accurate diagnosis. The image quality evaluation and reconstruction process effects are important tools in clinical routine. In the present work, these quality parameters were studied, and the effects of partial volume (PVE) for lesions of different sizes and geometries that are attributed to the limited resolution of the equipment. In dementia diagnosis, this effect can be confused with intake losses due to cerebral cortex atrophy. The evaluation was conducted by two phantoms of different shapes as suggested by (a) American College of Radiology (ACR) and (b) National Electrical Manufacturers Association (NEMA) for Contrast, Contrast-to-Noise Ratio (CNR) and Recovery Coefficient (RC) calculation versus lesions shape and size. Technetium-99m radionuclide was used in a local brain scintigraphy protocol, for proportions lesion to background of 2:1, 4:1, 6:1, 8:1 and 10:1. Fourteen reconstruction methods were used for each concentration applying different filters and algorithms. Before the analysis of all image properties, the conclusion is that the predominant effect is the partial volume, leading to errors of measurement of more than 80%. Furthermore, it was demonstrate that the most effective method of reconstruction is FBP with Metz filter, providing better contrast and contrast to noise ratio results. In addition, this method shows the best Recovery Coefficients correction for each lesion. The ACR phantom showed the best results assigned to a more precise reconstruction of a cylinder, which does not

Morphological image processing operators. Reduction of partial volume effects to improve 3D visualization based on CT data

International Nuclear Information System (INIS)

Beier, J.; Bittner, R.C.; Hosten, N.; Troeger, J.; Felix, R.

1998-01-01

Aim: The quality of segmentation and three-dimensional reconstruction of anatomical structures in tomographic slices is often impaired by disturbances due to partial volume effects (PVE). The potential for artefact reduction by use of the morphological image processing operators (MO) erosion and dilation is investigated. Results: For all patients under review, the artefacts caused by PVE were significantly reduced by erosion (lung: Mean SBR pre =1.67, SBR post =4.83; brain: SBR pre =1.06, SBR post =1.29) even with only a small number of iterations. Region dilation was applied to integrate further structures (e.g. at tumor borders) into a configurable neighbourhood for segmentation and quantitative analysis. Conclusions: The MO represent an efficient approach for the reduction of PVE artefacts in 3D-CT reconstructions and allow optimised visualization of individual objects. (orig./AJ) [de

Steam content of the two-phase flow in the Vk-50 boiling water cooled reactor draught section

International Nuclear Information System (INIS)

Fedulin, V.N.; Shmelev, V.E.; Solodkij, V.A.; Bartolomej, G.G.

1983-01-01

Results are presented of experimental investigation of the two-phase steam-water coolant flow hydrodynamics within the VK-50 reactor draught section. On the basis of the analysis of the obtained data a two-phase coolant flow model in a large diameter channel is proposed. It is shown that the steam-content distribution in the volume of the draught section has a pronounced non-equilibrium character manifested in the steam migration from the periphery to the central region. A minimum value of the steam content at the periphery is attained at the 0.7-1.0 m height; it is followed by a partial steam content levelling over the section. However the total steam content levelling over the cross section of the draught section does not take place. The steam distribution in the water layer over the draught section (overflow zone) is also nonuniform over the reactor section. The non-uniform steam distribution enchances with reduction nn pressure

Impact of motion compensation and partial volume correction for 18F-NaF PET/CT imaging of coronary plaque

Science.gov (United States)

Cal-González, J.; Tsoumpas, C.; Lassen, M. L.; Rasul, S.; Koller, L.; Hacker, M.; Schäfers, K.; Beyer, T.

2018-01-01

Recent studies have suggested that 18F-NaF-PET enables visualization and quantification of plaque micro-calcification in the coronary tree. However, PET imaging of plaque calcification in the coronary arteries is challenging because of the respiratory and cardiac motion as well as partial volume effects. The objective of this work is to implement an image reconstruction framework, which incorporates compensation for respiratory as well as cardiac motion (MoCo) and partial volume correction (PVC), for cardiac 18F-NaF PET imaging in PET/CT. We evaluated the effect of MoCo and PVC on the quantification of vulnerable plaques in the coronary arteries. Realistic simulations (Biograph TPTV, Biograph mCT) and phantom acquisitions (Biograph mCT) were used for these evaluations. Different uptake values in the calcified plaques were evaluated in the simulations, while three ‘plaque-type’ lesions of 36, 31 and 18 mm3 were included in the phantom experiments. After validation, the MoCo and PVC methods were applied in four pilot NaF-PET patient studies. In all cases, the MoCo-based image reconstruction was performed using the STIR software. The PVC was obtained from a local projection (LP) method, previously evaluated in preclinical and clinical PET. The results obtained show a significant increase of the measured lesion-to-background ratios (LBR) in the MoCo  +  PVC images. These ratios were further enhanced when using directly the tissue-activities from the LP method, making this approach more suitable for the quantitative evaluation of coronary plaques. When using the LP method on the MoCo images, LBR increased between 200% and 1119% in the simulated data, between 212% and 614% in the phantom experiments and between 46% and 373% in the plaques with positive uptake observed in the pilot patients. In conclusion, we have built and validated a STIR framework incorporating MoCo and PVC for 18F-NaF PET imaging of coronary plaques. First results indicate an improved

A multiresolution image based approach for correction of partial volume effects in emission tomography

International Nuclear Information System (INIS)

Boussion, N; Hatt, M; Lamare, F; Bizais, Y; Turzo, A; Rest, C Cheze-Le; Visvikis, D

2006-01-01

Partial volume effects (PVEs) are consequences of the limited spatial resolution in emission tomography. They lead to a loss of signal in tissues of size similar to the point spread function and induce activity spillover between regions. Although PVE can be corrected for by using algorithms that provide the correct radioactivity concentration in a series of regions of interest (ROIs), so far little attention has been given to the possibility of creating improved images as a result of PVE correction. Potential advantages of PVE-corrected images include the ability to accurately delineate functional volumes as well as improving tumour-to-background ratio, resulting in an associated improvement in the analysis of response to therapy studies and diagnostic examinations, respectively. The objective of our study was therefore to develop a methodology for PVE correction not only to enable the accurate recuperation of activity concentrations, but also to generate PVE-corrected images. In the multiresolution analysis that we define here, details of a high-resolution image H (MRI or CT) are extracted, transformed and integrated in a low-resolution image L (PET or SPECT). A discrete wavelet transform of both H and L images is performed by using the 'a trous' algorithm, which allows the spatial frequencies (details, edges, textures) to be obtained easily at a level of resolution common to H and L. A model is then inferred to build the lacking details of L from the high-frequency details in H. The process was successfully tested on synthetic and simulated data, proving the ability to obtain accurately corrected images. Quantitative PVE correction was found to be comparable with a method considered as a reference but limited to ROI analyses. Visual improvement and quantitative correction were also obtained in two examples of clinical images, the first using a combined PET/CT scanner with a lymphoma patient and the second using a FDG brain PET and corresponding T1-weighted MRI in

Two-nucleon higher partial-wave scattering from lattice QCD

Directory of Open Access Journals (Sweden)

Evan Berkowitz

2017-02-01

Full Text Available We present a determination of nucleon-nucleon scattering phase shifts for ℓ≥0. The S, P, D and F phase shifts for both the spin-triplet and spin-singlet channels are computed with lattice Quantum ChromoDynamics. For ℓ>0, this is the first lattice QCD calculation using the Lüscher finite-volume formalism. This required the design and implementation of novel lattice methods involving displaced sources and momentum-space cubic sinks. To demonstrate the utility of our approach, the calculations were performed in the SU(3-flavor limit where the light quark masses have been tuned to the physical strange quark mass, corresponding to mπ=mK≈800 MeV. In this work, we have assumed that only the lowest partial waves contribute to each channel, ignoring the unphysical partial wave mixing that arises within the finite-volume formalism. This assumption is only valid for sufficiently low energies; we present evidence that it holds for our study using two different channels. Two spatial volumes of V≈(3.5 fm3 and V≈(4.6 fm3 were used. The finite-volume spectrum is extracted from the exponential falloff of the correlation functions. Said spectrum is mapped onto the infinite volume phase shifts using the generalization of the Lüscher formalism for two-nucleon systems.

Partial molar volumes of organic solutes in water. XXIV. Selected alkane-α,ω-diols at temperatures T = 298 K to 573 K and pressures up to 30 MPa

International Nuclear Information System (INIS)

Cibulka, Ivan; Hnědkovský, Lubomír

2013-01-01

Highlights: • Standard molar volumes of three alkane-α,ω-diols (C 5 , C 8 , C 9 ) in water are presented. • Data were obtained in the range T from (298 to 573) K and p up to 30 MPa. • Dependences on carbon atom number, temperature, and pressure are analysed. -- Abstract: Density data for dilute aqueous solutions of three alkane-α,ω-diols (pentane-1,5-diol, octane-1,8-diol, nonane-1,9-diol) are presented together with standard molar volumes (partial molar volumes at infinite dilution) calculated from the experimental data. The measurements were performed at temperatures from T = 298 K up to T = 573 K. Experimental pressures were slightly above the saturation vapour pressure of water, and (15 and 30) MPa. The data were obtained using a high-temperature high-pressure flow vibrating-tube densimeter. Measured standard molar volumes were combined with data previously published for other members of the homologous series and discussed. Experimental standard molar volumes were correlated as a function of temperature and pressure using an empirical polynomial function. Dependences of standard molar volumes on temperature and pressure were analysed. Contributions of the methylene group to the standard molar volume were also evaluated and discussed

Changes of pituitary gland volume in Kennedy disease.

Science.gov (United States)

Pieper, C C; Teismann, I K; Konrad, C; Heindel, W L; Schiffbauer, H

2013-12-01

Kennedy disease is a rare X-linked neurodegenerative disorder caused by a CAG repeat expansion in the first exon of the androgen-receptor gene. Apart from neurologic signs, this mutation can cause a partial androgen insensitivity syndrome with typical alterations of gonadotropic hormones produced by the pituitary gland. The aim of the present study was therefore to evaluate the impact of Kennedy disease on pituitary gland volume under the hypothesis that endocrinologic changes caused by partial androgen insensitivity may lead to morphologic changes (ie, hypertrophy) of the pituitary gland. Pituitary gland volume was measured in sagittal sections of 3D T1-weighted 3T-MR imaging data of 8 patients with genetically proven Kennedy disease and compared with 16 healthy age-matched control subjects by use of Multitracer by a blinded, experienced radiologist. The results were analyzed by a univariant ANOVA with total brain volume as a covariant. Furthermore, correlation and linear regression analyses were performed for pituitary volume, patient age, disease duration, and CAG repeat expansion length. Intraobserver reliability was evaluated by means of the Pearson correlation coefficient. Pituitary volume was significantly larger in patients with Kennedy disease (636 [±90] mm(3)) than in healthy control subjects (534 [±91] mm(3)) (P = .041). There was no significant difference in total brain volume (P = .379). Control subjects showed a significant decrease in volume with age (r = -0.712, P = .002), whereas there was a trend to increasing gland volume in patients with Kennedy disease (r = 0.443, P = .272). Gland volume correlated with CAG repeat expansion length in patients (r = 0.630, P = .047). The correlation coefficient for intraobserver reliability was 0.94 (P pituitary volume that correlated with the CAG repeat expansion length. This could reflect hypertrophy as the result of elevated gonadotropic hormone secretion caused by the androgen receptor mutation with partial

Comparison of the effect of a single dose of erythromycin with pantoprazole on gastric content volume and acidity in elective general surgery patients

Science.gov (United States)

Bhatia, Nidhi; Palta, Sanjeev; Arora, Kanika

2011-01-01

Introduction: Pulmonary aspiration of gastric contents remains one of the most feared complications of anesthesia. A gastric pH of 2.5 or less and a volume of 25 ml (0.4 ml/kg body weight) or more in average adult patients are considered critical factors for the development of pulmonary damage in adults. Materials and Methods: This study compared the efficacy of a single oral dose of erythromycin (a macrolide antibiotic) with oral pantoprazole (a proton pump inhibitor) on pre-operative gastric fluid volume and pH in a prospective, randomized, double-blind controlled fashion in 80 adult patients (of ASA physical status I and II) planned for elective surgery under general anesthesia. Patients were divided into two groups of 40 patients each. The pantoprazole group (Group I) received oral pantoprazole 40 mg and the erythromycin group (Group II) received oral erythromycin 250 mg at least 1 h prior to the induction of anesthesia. After tracheal intubation, gastric fluid was aspirated via a Salem Sump tube and its volume and pH were measured. Results: Although both erythromycin and pantoprazole decreased the gastric fluid volume to a similar extent, the decrease in gastric fluid acidity by pantoprazole was significantly greater than that by erythromycin. The proportion of patients at risk of pulmonary aspiration according to traditional criteria, i.e. pH ≤2.5 and volume ≥25ml, was lower in the pantoprazole group. Conclusion: Administration of pantoprazole was found to be more useful than a sub-therapeutic dose of erythromycin in decreasing both volume and acidity of gastric content. PMID:21772679

Comparison of the effect of a single dose of erythromycin with pantoprazole on gastric content volume and acidity in elective general surgery patients

Directory of Open Access Journals (Sweden)

Nidhi Bhatia

2011-01-01

Full Text Available Introduction: Pulmonary aspiration of gastric contents remains one of the most feared complications of anesthesia. A gastric pH of 2.5 or less and a volume of 25 ml (0.4 ml/kg body weight or more in average adult patients are considered critical factors for the development of pulmonary damage in adults. Materials and Methods: This study compared the efficacy of a single oral dose of erythromycin (a macrolide antibiotic with oral pantoprazole (a proton pump inhibitor on pre-operative gastric fluid volume and pH in a prospective, randomized, double-blind controlled fashion in 80 adult patients (of ASA physical status I and II planned for elective surgery under general anesthesia. Patients were divided into two groups of 40 patients each. The pantoprazole group (Group I received oral pantoprazole 40 mg and the erythromycin group (Group II received oral erythromycin 250 mg at least 1 h prior to the induction of anesthesia. After tracheal intubation, gastric fluid was aspirated via a Salem Sump tube and its volume and pH were measured. Results: Although both erythromycin and pantoprazole decreased the gastric fluid volume to a similar extent, the decrease in gastric fluid acidity by pantoprazole was significantly greater than that by erythromycin. The proportion of patients at risk of pulmonary aspiration according to traditional criteria, i.e. pH ≤2.5 and volume ≥25ml, was lower in the pantoprazole group. Conclusion: Administration of pantoprazole was found to be more useful than a sub-therapeutic dose of erythromycin in decreasing both volume and acidity of gastric content.

Organic tank safety project: Effect of water partial pressure on the equilibrium water contents of waste samples from Hanford Tank 241-BY-108

International Nuclear Information System (INIS)

Scheele, R.D.; Bredt, P.R.; Sell, R.L.

1997-02-01

Water content plays a crucial role in the strategy developed by Webb et al. to prevent propagating or sustainable chemical reactions in the organic-bearing wastes stored in the 20 Organic Tank Watch List tanks at the US Department of Energy's Hanford Site. Because of water's importance in ensuring that the organic-bearing wastes continue to be stored safely, Duke Engineering and Services Hanford commissioned the Pacific Northwest National Laboratory (PNNL) to investigate the effect of water partial pressure (P H2O ) on the water content of organic-bearing or representative wastes. Of the various interrelated controlling factors affecting the water content in wastes, P H2O is the most susceptible to being controlled by the and Hanford Site's environmental conditions and, if necessary, could be managed to maintain the water content at an acceptable level or could be used to adjust the water content back to an acceptable level. Of the various waste types resulting from weapons production and waste-management operations at the Hanford Site, Webb et al. determined that saltcake wastes are the most likely to require active management to maintain the wastes in a Conditionally Safe condition. A Conditionally Safe waste is one that satisfies the waste classification criteria based on water content alone or a combination of water content and either total organic carbon (TOC) content or waste energetics. To provide information on the behavior of saltcake wastes, two waste samples taken from Tank 241-BY-108 (BY-108) were selected for study, even though BY-108 is not on the Organic Tanks Watch List because of their ready availability and their similarity to some of the organic-bearing saltcakes

A method for volume determination of the orbit and its contents by high resolution axial tomography and quantitative digital image analysis.

Science.gov (United States)

Cooper, W C

1985-01-01

The various congenital and acquired conditions which alter orbital volume are reviewed. Previous investigative work to determine orbital capacity is summarized. Since these studies were confined to postmortem evaluations, the need for a technique to measure orbital volume in the living state is presented. A method for volume determination of the orbit and its contents by high-resolution axial tomography and quantitative digital image analysis is reported. This procedure has proven to be accurate (the discrepancy between direct and computed measurements ranged from 0.2% to 4%) and reproducible (greater than 98%). The application of this method to representative clinical problems is presented and discussed. The establishment of a diagnostic system versatile enough to expand the usefulness of computerized axial tomography and polytomography should add a new dimension to ophthalmic investigation and treatment.

Partial muscle carnitine palmitoyltransferase-A deficiency

Energy Technology Data Exchange (ETDEWEB)

Ross, N.S.; Hoppel, C.L.

1987-01-02

After initiation of ibuprofen therapy, a 45-year-old woman developed muscle weakness and tenderness with rhabdomyolysis, culminating in respiratory failure. A muscle biopsy specimen showed a vacuolar myopathy, and markedly decreased muscle carnitine content and carnitine palmitoyltransferase activity. Following recovery, muscle carnitine content was normal but carnitine palmitoyltransferase activity was still abnormally low. The ratio of palmitoyl-coenzyme A plus carnitine to palmitoylcarnitine oxidation by muscle mitochondria isolated from the patient was markedly decreased. The authors conclude that transiently decreased muscle carnitine content interacted with partial deficiency of carnitine palmitoyltransferase-A to produce rhabdomyolysis and respiratory failure and that ibuprofen may have precipitated the clinical event.

Partial muscle carnitine palmitoyltransferase-A deficiency

International Nuclear Information System (INIS)

Ross, N.S.; Hoppel, C.L.

1987-01-01

After initiation of ibuprofen therapy, a 45-year-old woman developed muscle weakness and tenderness with rhabdomyolysis, culminating in respiratory failure. A muscle biopsy specimen showed a vacuolar myopathy, and markedly decreased muscle carnitine content and carnitine palmitoyltransferase activity. Following recovery, muscle carnitine content was normal but carnitine palmitoyltransferase activity was still abnormally low. The ratio of palmitoyl-coenzyme A plus carnitine to palmitoylcarnitine oxidation by muscle mitochondria isolated from the patient was markedly decreased. The authors conclude that transiently decreased muscle carnitine content interacted with partial deficiency of carnitine palmitoyltransferase-A to produce rhabdomyolysis and respiratory failure and that ibuprofen may have precipitated the clinical event

PET imaging of thin objects: measuring the effects of positron range and partial-volume averaging in the leaf of Nicotiana tabacum

Energy Technology Data Exchange (ETDEWEB)

Alexoff, David L., E-mail: alexoff@bnl.gov; Dewey, Stephen L.; Vaska, Paul; Krishnamoorthy, Srilalan; Ferrieri, Richard; Schueller, Michael; Schlyer, David J.; Fowler, Joanna S.

2011-02-15

Introduction: PET imaging in plants is receiving increased interest as a new strategy to measure plant responses to environmental stimuli and as a tool for phenotyping genetically engineered plants. PET imaging in plants, however, poses new challenges. In particular, the leaves of most plants are so thin that a large fraction of positrons emitted from PET isotopes ({sup 18}F, {sup 11}C, {sup 13}N) escape while even state-of-the-art PET cameras have significant partial-volume errors for such thin objects. Although these limitations are acknowledged by researchers, little data have been published on them. Methods: Here we measured the magnitude and distribution of escaping positrons from the leaf of Nicotiana tabacum for the radionuclides {sup 18}F, {sup 11}C and {sup 13}N using a commercial small-animal PET scanner. Imaging results were compared to radionuclide concentrations measured from dissection and counting and to a Monte Carlo simulation using GATE (Geant4 Application for Tomographic Emission). Results: Simulated and experimentally determined escape fractions were consistent. The fractions of positrons (mean{+-}S.D.) escaping the leaf parenchyma were measured to be 59{+-}1.1%, 64{+-}4.4% and 67{+-}1.9% for {sup 18}F, {sup 11}C and {sup 13}N, respectively. Escape fractions were lower in thicker leaf areas like the midrib. Partial-volume averaging underestimated activity concentrations in the leaf blade by a factor of 10 to 15. Conclusions: The foregoing effects combine to yield PET images whose contrast does not reflect the actual activity concentrations. These errors can be largely corrected by integrating activity along the PET axis perpendicular to the leaf surface, including detection of escaped positrons, and calculating concentration using a measured leaf thickness.

The Effects of Design Strength, Fly Ash Content and Curing Method on Compressive Strength of High Volume Fly Ash Concrete: A Design of Experimental

OpenAIRE

Solikin Mochamad; Setiawan Budi

2017-01-01

High volume fly ash concrete becomes one of alternatives to produce green concrete as it uses waste material and significantly reduces the utilization of Portland cement in concrete production. Although using less cement, its compressive strength is comparable to ordinary Portland cement (hereafter OPC) and the its durability increases significantly. This paper reports investigation on the effect of design strength, fly ash content and curing method on compressive strength of High Volume Fly ...

Solubility comparison and partial molar volumes of 1,2-hexanediol before and after end-group modification by methyl oxalyl chloride and ethyl oxalyl monochloride in supercritical CO2

International Nuclear Information System (INIS)

Zhao, Lu; Yang, Hai-Jian; Cai, Zhuofu

2013-01-01

Highlights: ► Two new “CO 2 -philic” compounds were designed and synthesized. ► The tested solubility data were calculated and correlated with two models. ► Satisfactory agreements were obtained between the tested and calculated data. ► The partial molar volumes V ¯ 2 for three compounds were estimated. - Abstract: Bis(methoxy oxalic)-1,2-haxenediester and bis(ethoxy oxalic)-1,2-haxenediester were synthesized by modifying the end groups of 1,2-hexanediol with methyl oxalyl chloride and ethyl oxalyl monochloride. The solubilities of all three compounds in supercritical carbon dioxide were determined at different conditions of pressures (8.8 to 18.8) MPa and temperatures (313, 333, and 353) K. Then, the solubility data were correlated with the Bartle model and the Chrastil model. The average absolute relative deviation (AARD) for the Bartle model was in the range of (3.89 to 25.46)% which is within a good approximation. The Chrastil model also showed satisfactory agreement and the AARD was in the range of (3.70 to 16.92)%. Furthermore, the partial molar volumes of those compounds were estimated following the theory developed by Kumar and Johnston.

South-Tibetan partially molten batholiths: geophysical characterization and petrological assessment of their origin

Science.gov (United States)

Hetényi, G.; Pistone, M.; Nabelek, P. I.; Baumgartner, L. P.

2017-12-01

Zones of partial melt in the middle crust of Lhasa Block, Southern Tibet, have been geophysically observed as seismically reflective "bright spots" in the past 20 years. These batholiths bear important relevance for geodynamics as they serve as the principal observation at depth supporting channel-flow models in the Himalaya-Tibet orogen. Here we assess the spatial abundance of and partial melt volume fraction within these crustal batholiths, and establish lower and upper estimate bounds using a joint geophysical-petrological approach.Geophysical imaging constrains the abundance of partial melt zones to 5.6 km3 per surface-km2 on average (minimum: 3.1 km3/km2, maximum: 7.6 km3/km2 over the mapped area). Physical properties detected by field geophysics and interpreted by laboratory measurements constrain the amount of partial melt to be between 5 and 26 percent.We evaluate the compatibility of these estimates with petrological modeling based on geotherms, crustal bulk rock compositions and water contents consistent with the Lhasa Block. These simulations determine: (a) the physico-chemical conditions of melt generation at the base of the Tibetan crust and its transport and emplacement in the middle crust; (b) the melt percentage produced at the source, transported and emplaced to form the observed "bright spots". Two main mechanisms are considered: (1) melting induced by fluids produced during mineral dehydration reactions in the underthrusting Indian lower crust; (2) dehydration-melting reactions caused by heating within the Tibetan crust. We find that both mechanisms demonstrate first-order match in explaining the formation of the partially molten "bright spots". Thermal modelling shows that the Lhasa Block batholiths have only small amounts of melt and only for geologically short times (features of the geodynamic evolution. Their transience excludes both long-distance and long-lasting channel flow transport in Tibet.

Association between partial-volume corrected SUVmax and Oncotype DX recurrence score in early-stage, ER-positive/HER2-negative invasive breast cancer.

Science.gov (United States)

Lee, Su Hyun; Ha, Seunggyun; An, Hyun Joon; Lee, Jae Sung; Han, Wonshik; Im, Seock-Ah; Ryu, Han Suk; Kim, Won Hwa; Chang, Jung Min; Cho, Nariya; Moon, Woo Kyung; Cheon, Gi Jeong

2016-08-01

Oncotype DX, a 21-gene expression assay, provides a recurrence score (RS) which predicts prognosis and the benefit from adjuvant chemotherapy in patients with early-stage, estrogen receptor-positive (ER-positive), and human epidermal growth factor receptor 2-negative (HER2-negative) invasive breast cancer. However, Oncotype DX tests are expensive and not readily available in all institutions. The purpose of this study was to investigate whether metabolic parameters on (18)F-FDG PET/CT are associated with the Oncotype DX RS and whether (18)F-FDG PET/CT can be used to predict the Oncotype DX RS. The study group comprised 38 women with stage I/II, ER-positive/HER2-negative invasive breast cancer who underwent pretreatment (18)F-FDG PET/CT and Oncotype DX testing. On PET/CT, maximum (SUVmax) and average standardized uptake values, metabolic tumor volume, and total lesion glycolysis were measured. Partial volume-corrected SUVmax (PVC-SUVmax) determined using the recovery coefficient method was also evaluated. Oncotype DX RS (0 - 100) was categorized as low (negative breast cancer.

Anatomy-based reconstruction of FDG-PET images with implicit partial volume correction improves detection of hypometabolic regions in patients with epilepsy due to focal cortical dysplasia diagnosed on MRI

Energy Technology Data Exchange (ETDEWEB)

Goffin, Karolien; Baete, Kristof; Nuyts, Johan; Laere, Koen van [University Hospital Leuven, Division of Nuclear Medicine and Medical Imaging Center, Leuven (Belgium); Van Paesschen, Wim [University Hospital Leuven, Neurology Department, Leuven (Belgium); Dupont, Patrick [University Hospital Leuven, Division of Nuclear Medicine and Medical Imaging Center, Leuven (Belgium); University Hospital Leuven, Laboratory of Cognitive Neurology, Leuven (Belgium); Palmini, Andre [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre Epilepsy Surgery Program, Hospital Sao Lucas, Porto Alegre (Brazil)

2010-06-15

Detection of hypometabolic areas on interictal FDG-PET images for assessing the epileptogenic zone is hampered by partial volume effects. We evaluated the performance of an anatomy-based maximum a-posteriori (A-MAP) reconstruction algorithm which combined noise suppression with correction for the partial volume effect in the detection of hypometabolic areas in patients with focal cortical dysplasia (FCD). FDG-PET images from 14 patients with refractory partial epilepsy were reconstructed using A-MAP and maximum likelihood (ML) reconstruction. In all patients, presurgical evaluation showed that FCD represented the epileptic lesion. Correspondence between the FCD location and regional metabolism on a predefined atlas was evaluated. An asymmetry index of FCD to normal cortex was calculated. Hypometabolism at the FCD location was detected in 9/14 patients (64%) using ML and in 10/14 patients (71%) using A-MAP reconstruction. Hypometabolic areas outside the FCD location were detected in 12/14 patients (86%) using ML and in 11/14 patients (79%) using A-MAP reconstruction. The asymmetry index was higher using A-MAP reconstruction (0.61, ML 0.49, p=0.03). The A-MAP reconstruction algorithm improved visual detection of epileptic FCD on brain FDG-PET images compared to ML reconstruction, due to higher contrast and better delineation of the lesion. This improvement failed to reach significance in our small sample. Hypometabolism outside the lesion is often present, consistent with the observation that the functional deficit zone tends to be larger than the epileptogenic zone. (orig.)

Anatomy-based reconstruction of FDG-PET images with implicit partial volume correction improves detection of hypometabolic regions in patients with epilepsy due to focal cortical dysplasia diagnosed on MRI

International Nuclear Information System (INIS)

Goffin, Karolien; Baete, Kristof; Nuyts, Johan; Laere, Koen van; Van Paesschen, Wim; Dupont, Patrick; Palmini, Andre

2010-01-01

Detection of hypometabolic areas on interictal FDG-PET images for assessing the epileptogenic zone is hampered by partial volume effects. We evaluated the performance of an anatomy-based maximum a-posteriori (A-MAP) reconstruction algorithm which combined noise suppression with correction for the partial volume effect in the detection of hypometabolic areas in patients with focal cortical dysplasia (FCD). FDG-PET images from 14 patients with refractory partial epilepsy were reconstructed using A-MAP and maximum likelihood (ML) reconstruction. In all patients, presurgical evaluation showed that FCD represented the epileptic lesion. Correspondence between the FCD location and regional metabolism on a predefined atlas was evaluated. An asymmetry index of FCD to normal cortex was calculated. Hypometabolism at the FCD location was detected in 9/14 patients (64%) using ML and in 10/14 patients (71%) using A-MAP reconstruction. Hypometabolic areas outside the FCD location were detected in 12/14 patients (86%) using ML and in 11/14 patients (79%) using A-MAP reconstruction. The asymmetry index was higher using A-MAP reconstruction (0.61, ML 0.49, p=0.03). The A-MAP reconstruction algorithm improved visual detection of epileptic FCD on brain FDG-PET images compared to ML reconstruction, due to higher contrast and better delineation of the lesion. This improvement failed to reach significance in our small sample. Hypometabolism outside the lesion is often present, consistent with the observation that the functional deficit zone tends to be larger than the epileptogenic zone. (orig.)

Estimating alcohol content of traditional brew in Western Kenya using culturally relevant methods: the case for cost over volume.

Science.gov (United States)

Papas, Rebecca K; Sidle, John E; Wamalwa, Emmanuel S; Okumu, Thomas O; Bryant, Kendall L; Goulet, Joseph L; Maisto, Stephen A; Braithwaite, R Scott; Justice, Amy C

2010-08-01

Traditional homemade brew is believed to represent the highest proportion of alcohol use in sub-Saharan Africa. In Eldoret, Kenya, two types of brew are common: chang'aa, spirits, and busaa, maize beer. Local residents refer to the amount of brew consumed by the amount of money spent, suggesting a culturally relevant estimation method. The purposes of this study were to analyze ethanol content of chang'aa and busaa; and to compare two methods of alcohol estimation: use by cost, and use by volume, the latter the current international standard. Laboratory results showed mean ethanol content was 34% (SD = 14%) for chang'aa and 4% (SD = 1%) for busaa. Standard drink unit equivalents for chang'aa and busaa, respectively, were 2 and 1.3 (US) and 3.5 and 2.3 (Great Britain). Using a computational approach, both methods demonstrated comparable results. We conclude that cost estimation of alcohol content is more culturally relevant and does not differ in accuracy from the international standard.

What is the fundamental ion-specific series for anions and cations? Ion specificity in standard partial molar volumes of electrolytes and electrostriction in water and non-aqueous solvents.

Science.gov (United States)

Mazzini, Virginia; Craig, Vincent S J

2017-10-01

The importance of electrolyte solutions cannot be overstated. Beyond the ionic strength of electrolyte solutions the specific nature of the ions present is vital in controlling a host of properties. Therefore ion specificity is fundamentally important in physical chemistry, engineering and biology. The observation that the strengths of the effect of ions often follows well established series suggests that a single predictive and quantitative description of specific-ion effects covering a wide range of systems is possible. Such a theory would revolutionise applications of physical chemistry from polymer precipitation to drug design. Current approaches to understanding specific-ion effects involve consideration of the ions themselves, the solvent and relevant interfaces and the interactions between them. Here we investigate the specific-ion effects trends of standard partial molar volumes and electrostrictive volumes of electrolytes in water and eleven non-aqueous solvents. We choose these measures as they relate to bulk properties at infinite dilution, therefore they are the simplest electrolyte systems. This is done to test the hypothesis that the ions alone exhibit a specific-ion effect series that is independent of the solvent and unrelated to surface properties. The specific-ion effects trends of standard partial molar volumes and normalised electrostrictive volumes examined in this work show a fundamental ion-specific series that is reproduced across the solvents, which is the Hofmeister series for anions and the reverse lyotropic series for cations, supporting the hypothesis. This outcome is important in demonstrating that ion specificity is observed at infinite dilution and demonstrates that the complexity observed in the manifestation of specific-ion effects in a very wide range of systems is due to perturbations of solvent, surfaces and concentration on the underlying fundamental series. This knowledge will guide a general understanding of specific

Landsliding in partially saturated materials

Science.gov (United States)

Godt, J.W.; Baum, R.L.; Lu, N.

2009-01-01

[1] Rainfall-induced landslides are pervasive in hillslope environments around the world and among the most costly and deadly natural hazards. However, capturing their occurrence with scientific instrumentation in a natural setting is extremely rare. The prevailing thinking on landslide initiation, particularly for those landslides that occur under intense precipitation, is that the failure surface is saturated and has positive pore-water pressures acting on it. Most analytic methods used for landslide hazard assessment are based on the above perception and assume that the failure surface is located beneath a water table. By monitoring the pore water and soil suction response to rainfall, we observed shallow landslide occurrence under partially saturated conditions for the first time in a natural setting. We show that the partially saturated shallow landslide at this site is predictable using measured soil suction and water content and a novel unified effective stress concept for partially saturated earth materials. Copyright 2009 by the American Geophysical Union.

二氧化碳与2-丁醇二元体系在高压下的亨利系数和偏摩尔体积性质计算%Calculation of Henry's coefficient and partial molar volume of carbon dioxide in 2-butanol at elevated pressures

Institute of Scientific and Technical Information of China (English)

田爱琴; 孙洪博; 陈文涛; 王琳

2012-01-01

Based on vapor-liquid phase equilibria data for CO2+2-butanol binary system from 323K to 353K by constant-volume visual high-pressure cell, the solubility model of CO2 in 2-butanol was established with Krichevsky-Kasarnovsky equation. Henry's coefficients and partial molar volumes of CO2 at infinite dilution were calculated. Meanwhile, Partial molar volumes of CO2 and 2-butanol at equilibrium were calculated from partial molar volumes properties together with Peng-Robinson equation of state and Van der Waals-2 mixed rule. The results showed that Henry's coefficients and partial molar volumes of CO2 at infinite dilution were both the function of temperature, and Henry's coefficients decreased with temperature. The partial molar volumes of CO2 at infinite dilution were negative and the magnitudes decreased with temperature. The calculated effects of partial molar volumes of vapor and liquid phase at equilibrium showed that the partial molar volumes of CO2 and 2-butanol in liquid phase were positive, but in vapor the partial molar volumes of CO2 were negative and the partial molar volumes of 2-butanol were positive. The research provided theoretical basis for deciding supercritical extraction conditions and instructing industrial production.%利用固定体积可视高压釜测量出的在323 K～353 K温度范围内的CO2与2-丁醇二元体系在高压下的汽液相平衡数据,根据Krichevsky-Kasarnovsky方程建立了CO2在液相中的溶解度模型,得到了该二元体系在高压下的亨利系数和CO2在无限稀释溶液中的偏摩尔体积等性质.同时根据偏摩尔体积性质和Peng-Robinson状态方程及Van der Waals-2混合规则来计算该体系在平衡状态下的气、液相的偏摩尔体积.结果表明CO2在2-丁醇中的亨利系数和CO2在无限稀释溶液中的偏摩尔体积均为温度的函数,CO2在2-丁醇中的亨利系数随温度的升高而降低.CO2在无限稀释溶液中的偏摩尔体积(V)1�

Simulation-based partial volume correction for dopaminergic PET imaging. Impact of segmentation accuracy

Energy Technology Data Exchange (ETDEWEB)

Rong, Ye; Winz, Oliver H. [University Hospital Aachen (Germany). Dept. of Nuclear Medicine; Vernaleken, Ingo [University Hospital Aachen (Germany). Dept. of Psychiatry, Psychotherapy and Psychosomatics; Goedicke, Andreas [University Hospital Aachen (Germany). Dept. of Nuclear Medicine; High Tech Campus, Philips Research Lab., Eindhoven (Netherlands); Mottaghy, Felix M. [University Hospital Aachen (Germany). Dept. of Nuclear Medicine; Maastricht University Medical Center (Netherlands). Dept. of Nuclear Medicine; Rota Kops, Elena [Forschungszentrum Juelich (Germany). Inst. of Neuroscience and Medicine-4

2015-07-01

Partial volume correction (PVC) is an essential step for quantitative positron emission tomography (PET). In the present study, PVELab, a freely available software, is evaluated for PVC in {sup 18}F-FDOPA brain-PET, with a special focus on the accuracy degradation introduced by various MR-based segmentation approaches. Methods Four PVC algorithms (M-PVC; MG-PVC; mMG-PVC; and R-PVC) were analyzed on simulated {sup 18}F-FDOPA brain-PET images. MR image segmentation was carried out using FSL (FMRIB Software Library) and SPM (Statistical Parametric Mapping) packages, including additional adaptation for subcortical regions (SPM{sub L}). Different PVC and segmentation combinations were compared with respect to deviations in regional activity values and time-activity curves (TACs) of the occipital cortex (OCC), caudate nucleus (CN), and putamen (PUT). Additionally, the PVC impact on the determination of the influx constant (K{sub i}) was assessed. Results Main differences between tissue-maps returned by three segmentation algorithms were found in the subcortical region, especially at PUT. Average misclassification errors in combination with volume reduction was found to be lowest for SPM{sub L} (PUT < 30%) and highest for FSL (PUT > 70%). Accurate recovery of activity data at OCC is achieved by M-PVC (apparent recovery coefficient varies between 0.99 and 1.10). The other three evaluated PVC algorithms have demonstrated to be more suitable for subcortical regions with MG-PVC and mMG-PVC being less prone to the largest tissue misclassification error simulated in this study. Except for M-PVC, quantification accuracy of K{sub i} for CN and PUT was clearly improved by PVC. Conclusions The regional activity value of PUT was appreciably overcorrected by most of the PVC approaches employing FSL or SPM segmentation, revealing the importance of accurate MR image segmentation for the presented PVC framework. The selection of a PVC approach should be adapted to the anatomical

Monitoring Heavy Metal Contents with Sphagnum Junghuhnianum Moss Bags in Relation to Traffic Volume in Wuxi, China

Directory of Open Access Journals (Sweden)

Rong Hu

2018-02-01

Full Text Available Despite its small size, a moss bag can reveal the different temporal and spatial deposition patterns of pollutants at a particular site; therefore, researchers can use moss bags to determine pollution sources and to put forward strategies for pollution control. Although the use of moss bags to monitor atmospheric pollution has been widely reported in Europe, there are few such empirical studies in China. Thus, in this study, bags containing the moss Sphagnum junghuhnianum were used to assess the concentrations of heavy metals (chromium (Cr, copper (Cu, lead (Pb, vanadium (V, and zinc (Zn at five sampling sites (four roads and a forest park during the summer and winter of 2012. According to the relative accumulation factor (RAF and contamination factor (CF results, pollution in winter was heavier than that in summer, and Cr was found to be the most contaminating, having the highest mean CF. There was a significant positive correlation (p < 0.05 between traffic volume and concentration for three heavy metals (Cr, Cu, and V in winter, whereas a significant positive correlation (p < 0.05 was observed between traffic volume and concentrations for four heavy metal elements (Cr, Pb, V, and Zn in summer, indicating a close relationship between heavy metal contents and traffic volume. Although there was substantial variation in the concentrations of the five heavy metals in the moss bags, significant correlations between heavy metals suggested that the contaminants originated from a common source, namely vehicle emissions. The results demonstrated that the four roads were subject to different degrees of pollution depending on the volume of traffic using each road. Therefore, the results of this study suggest that traffic volume is a major reason for heavy metal pollution.

Handbook of differential equations stationary partial differential equations

CERN Document Server

Chipot, Michel

2006-01-01

This handbook is volume III in a series devoted to stationary partial differential quations. Similarly as volumes I and II, it is a collection of self contained state-of-the-art surveys written by well known experts in the field. The topics covered by this handbook include singular and higher order equations, problems near critically, problems with anisotropic nonlinearities, dam problem, T-convergence and Schauder-type estimates. These surveys will be useful for both beginners and experts and speed up the progress of corresponding (rapidly developing and fascinating) areas of mathematics. Ke

Investigation of partial volume effect in different PET/CT systems: a comparison of results using the madeira phantom and the NEMA NU-2 2001 phantom

International Nuclear Information System (INIS)

Chipiga, L.; Sydoff, M.; Zvonova, I.; Bernhardsson, C.

2016-01-01

Positron emission tomography combined with computed tomography (PET/CT) is a quantitative technique used for diagnosing various diseases and for monitoring treatment response for different types of tumours. However, the accuracy of the data is limited by the spatial resolution of the system. In addition, the so-called partial volume effect (PVE) causes a blurring of image structures, which in turn may cause an underestimation of activity of a structure with high-activity content. In this study, a new phantom, MADEIRA (Minimising Activity and Dose with Enhanced Image quality by Radiopharmaceutical Administrations) for activity quantification in PET and single photon emission computed tomography (SPECT) was used to investigate the influence on the PVE by lesion size and tumour-to-background activity concentration ratio (TBR) in four different PET/CT systems. These measurements were compared with data from measurements with the NEMA NU-2 2001 phantom. The results with the MADEIRA phantom showed that the activity concentration (AC) values were closest to the true values at low ratios of TBR (<10) and reduced to 50 % of the actual AC values at high TBR (30-35). For all scanners, recovery of true values became closer to 1 with an increasing diameter of the lesion. The MADEIRA phantom showed good agreement with the results obtained from measurements with the NEMA NU-2 2001 phantom but allows for a wider range of possibilities in measuring image quality parameters. (authors)

GABA content within the ventromedial prefrontal cortex is related to trait anxiety.

Science.gov (United States)

Delli Pizzi, Stefano; Padulo, Caterina; Brancucci, Alfredo; Bubbico, Giovanna; Edden, Richard A; Ferretti, Antonio; Franciotti, Raffaella; Manippa, Valerio; Marzoli, Daniele; Onofrj, Marco; Sepede, Gianna; Tartaro, Armando; Tommasi, Luca; Puglisi-Allegra, Stefano; Bonanni, Laura

2016-05-01

The ventromedial prefrontal cortex (vmPFC) plays a key role in emotion processing and regulation. vmPFC dysfunction may lead to disinhibition of amygdala causing high anxiety levels. γ-Aminobutyric acid (GABA) inter-neurons within vmPFC shape the information flow to amygdala. Thus, we hypothesize that GABA content within vmPFC could be relevant to trait anxiety. Forty-three healthy volunteers aged between 20 and 88 years were assessed for trait anxiety with the Subscale-2 of the State-Trait-Anxiety Inventory (STAI-Y2) and were studied with proton magnetic resonance spectroscopy to investigate GABA and Glx (glutamate+glutamine) contents within vmPFC. Total creatine (tCr) was used as internal reference. Partial correlations assessed the association between metabolite levels and STAI-Y2 scores, removing the effect of possible nuisance factors including age, educational level, volumes of gray matter and white matter within magnetic resonance spectroscopy voxel. We observed a positive relationship between GABA/tCr and STAI-Y2 scores. No significant relationships were found between Glx/tCr and STAI-Y2 and between tCr/water and STAI-Y2. No differences were found between males and females as regards to age, STAI-Y2, GABA/tCr, Glx/tCr, tCr/water, gray matter and white matter volumes. We suggest a close relationship between GABA content within vmPFC and trait anxiety providing new insights in the physiology of emotional brain. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Water resources data, Idaho, 2004; Volume 1. Surface water records for Great Basin and Snake River basin above King Hill

Science.gov (United States)

Brennan, T.S.; Lehmann, A.K.; O'Dell, I.

2005-01-01

Water resources data for the 2004 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 209 stream-gaging stations and 8 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 39 stream-gaging stations and partial record sites, 3 lakes sites, and 395 groundwater wells; and water levels for 425 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Water resources data, Idaho, 2003; Volume 1. Surface water records for Great Basin and Snake River basin above King Hill

Science.gov (United States)

Brennan, T.S.; Lehmann, A.K.; O'Dell, I.

2004-01-01

Water resources data for the 2003 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 208 stream-gaging stations and 14 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 50 stream-gaging stations and partial record sites, 3 lakes sites, and 398 groundwater wells; and water levels for 427 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Hamiltonian partial differential equations and applications

CERN Document Server

Nicholls, David; Sulem, Catherine

2015-01-01

This book is a unique selection of work by world-class experts exploring the latest developments in Hamiltonian partial differential equations and their applications. Topics covered within are representative of the field’s wide scope, including KAM and normal form theories, perturbation and variational methods, integrable systems, stability of nonlinear solutions as well as applications to cosmology, fluid mechanics and water waves. The volume contains both surveys and original research papers and gives a concise overview of the above topics, with results ranging from mathematical modeling to rigorous analysis and numerical simulation. It will be of particular interest to graduate students as well as researchers in mathematics and physics, who wish to learn more about the powerful and elegant analytical techniques for Hamiltonian partial differential equations.

The Effects of Design Strength, Fly Ash Content and Curing Method on Compressive Strength of High Volume Fly Ash Concrete: A Design of Experimental

Directory of Open Access Journals (Sweden)

Solikin Mochamad

2017-01-01

Full Text Available High volume fly ash concrete becomes one of alternatives to produce green concrete as it uses waste material and significantly reduces the utilization of Portland cement in concrete production. Although using less cement, its compressive strength is comparable to ordinary Portland cement (hereafter OPC and the its durability increases significantly. This paper reports investigation on the effect of design strength, fly ash content and curing method on compressive strength of High Volume Fly Ash Concrete. The experiment and data analysis were prepared using minitab, a statistic software for design of experimental. The specimens were concrete cylinder with diameter of 15 cm and height of 30 cm, tested for its compressive strength at 56 days. The result of the research demonstrates that high volume fly ash concrete can produce comparable compressive strength which meets the strength of OPC design strength especially for high strength concrete. In addition, the best mix proportion to achieve the design strength is the combination of high strength concrete and 50% content of fly ash. Moreover, the use of spraying method for curing method of concrete on site is still recommended as it would not significantly reduce the compressive strength result.

Improving the developability profile of pyrrolidine progesterone receptor partial agonists

Energy Technology Data Exchange (ETDEWEB)

Kallander, Lara S.; Washburn, David G.; Hoang, Tram H.; Frazee, James S.; Stoy, Patrick; Johnson, Latisha; Lu, Qing; Hammond, Marlys; Barton, Linda S.; Patterson, Jaclyn R.; Azzarano, Leonard M.; Nagilla, Rakesh; Madauss, Kevin P.; Williams, Shawn P.; Stewart, Eugene L.; Duraiswami, Chaya; Grygielko, Eugene T.; Xu, Xiaoping; Laping, Nicholas J.; Bray, Jeffrey D.; Thompson, Scott K. (GSKPA)

2010-09-17

The previously reported pyrrolidine class of progesterone receptor partial agonists demonstrated excellent potency but suffered from serious liabilities including hERG blockade and high volume of distribution in the rat. The basic pyrrolidine amine was intentionally converted to a sulfonamide, carbamate, or amide to address these liabilities. The evaluation of the degree of partial agonism for these non-basic pyrrolidine derivatives and demonstration of their efficacy in an in vivo model of endometriosis is disclosed herein.

Optimal partial-arcs in VMAT treatment planning

International Nuclear Information System (INIS)

Wala, Jeremiah; Salari, Ehsan; Chen Wei; Craft, David

2012-01-01

We present a method for improving the delivery efficiency of VMAT by extending the recently published VMAT treatment planning algorithm vmerge to automatically generate optimal partial-arc plans. A high-quality initial plan is created by solving a convex multicriteria optimization problem using 180 equi-spaced beams. This initial plan is used to form a set of dose constraints, and a set of partial-arc plans is created by searching the space of all possible partial-arc plans that satisfy these constraints. For each partial-arc, an iterative fluence map merging and sequencing algorithm (vmerge) is used to improve the delivery efficiency. Merging continues as long as the dose quality is maintained above a user-defined threshold. The final plan is selected as the partial-arc with the lowest treatment time. The complete algorithm is called pmerge. Partial-arc plans are created using pmerge for a lung, liver and prostate case, with final treatment times of 127, 245 and 147 s. Treatment times using full arcs with vmerge are 211, 357 and 178 s. The mean doses to the critical structures for the vmerge and pmerge plans are kept within 5% of those in the initial plan, and the target volume covered by the prescription isodose is maintained above 98% for the pmerge and vmerge plans. Additionally, we find that the angular distribution of fluence in the initial plans is predictive of the start and end angles of the optimal partial-arc. We conclude that VMAT delivery efficiency can be improved by employing partial-arcs without compromising dose quality, and that partial-arcs are most applicable to cases with non-centralized targets. (paper)

Plasma volume changes during hypoglycaemia

DEFF Research Database (Denmark)

Hilsted, J; Frandsen, Henrik Lund; Christensen, N J

1991-01-01

-induced hypoglycaemia with total autonomic blockade (alpha-adrenoceptor blockade combined with beta-adrenoceptor blockade and atropine); and insulin-induced hypoglycaemia without any autonomic blockade. In the experiments without autonomic blockade the peripheral venous hematocrit increased, plasma volume decreased......, intravascular albumin content decreased and the transcapillary escape rate of albumin increased. In both experiments with autonomic blockade the increase in venous haematocrit was abolished, yet plasma volume decreased, intravascular albumin content decreased and the transcapillary escape rate of albumin...... increased in these experiments. Thus, the changes in plasma volume and composition in response to hypoglycaemia are due to the combined actions of adrenaline and of insulin....

Organic Tank Safety Project: Effect of water partial pressure on the equilibrium water content of waste samples from Hanford Tank 241-U-105

International Nuclear Information System (INIS)

Scheele, R.D.; Bredt, P.R.; Sell, R.L.

1997-09-01

Water content plays a crucial role in the strategy developed by Webb et al. to prevent propagating or sustainable chemical reactions in the organic-bearing wastes stored in the 20 Organic Tank Watch List tanks at the U.S. Department of Energy''s Hanford Site. Because of water''s importance in ensuring that the organic-bearing wastes continue to be stored safely, Duke Engineering and Services Hanford commissioned the Pacific Northwest National Laboratory to investigate the effect of water partial pressure (P H2O ) on the water content of organic-bearing or representative wastes. Of the various interrelated controlling factors affecting the water content in wastes, P H2O is the most susceptible to being controlled by the and Hanford Site''s environmental conditions and, if necessary, could be managed to maintain the water content at an acceptable level or could be used to adjust the water content back to an acceptable level. Of the various waste types resulting from weapons production and waste-management operations at the Hanford Site, determined that saltcake wastes are the most likely to require active management to maintain the wastes in a Conditionally Safe condition. Webb et al. identified Tank U-105 as a Conditionally Safe saltcake tank. A Conditionally Safe waste is one that is currently safe based on waste classification criteria but could, if dried, be classified as open-quotes Unsafe.close quotes To provide information on the behavior of organic-bearing wastes, the Westinghouse Hanford Company provided us with four waste samples taken from Tank 241-U-105 (U-105) to determine the effect of P H2O on their equilibrium water content

Two-fold sustainability – Adobe with sawdust as partial sand replacement

Science.gov (United States)

Jokhio, Gul A.; Syed Mohsin, Sharifah M.; Gul, Yasmeen

2018-04-01

Adobe is a material that is economic, environment friendly, and provides better indoor air quality. The material required for the preparation of adobe include clay, sand, and sometimes straw or other organic materials. These materials do not require industrial processing or transportation, however, sand mining has been recently posing a threat to the environment. Therefore, to enhance the existing sustainability of adobe, sand can be partially or fully replaced by other waste materials. This approach will not only solve the problem of excessive sand mining, it will also address the issue of waste management. Sawdust is one such waste material that can be used to partially replace sand in Adobe. This paper presents the results of compressive and flexural test carried out on Adobe samples with partial sand replacement by sawdust. The results show that about 4% sand replacement by volume produces higher compressive strength, whereas the flexural strength reduces with the use of sawdust. However, since flexural strength is not a critical property for adobe, it is concluded that replacing sand with sawdust by about 4% of volume will be beneficial.

Assessment of partial coalescence in whippable oil-in-water food emulsions.

Science.gov (United States)

Petrut, Raul Flaviu; Danthine, Sabine; Blecker, Christophe

2016-03-01

Partial coalescence influences to a great extent the properties of final food products such as ice cream and whipped toppings. In return, the partial coalescence occurrence and development are conditioned, in such systems, by the emulsion's intrinsic properties (e.g. solid fat content, fat crystal shape and size), formulation (e.g. protein content, surfactants presence) and extrinsic factors (e.g. cooling rate, shearing). A set of methods is available for partial coalescence investigation and quantification. These methods are critically reviewed in this paper, balancing the weaknesses of the methods in terms of structure alteration (for turbidity, dye dilution, etc.) and assumptions made for mathematical models (for particle size determination) with their advantages (good repeatability, high sensitivity, etc.). With the methods proposed in literature, the partial coalescence investigations can be conducted quantitatively and/or qualitatively. Good correlation were observed between some of the quantitative methods such as dye dilution, calorimetry, fat particle size; while a poor correlation was found in the case of solvent extraction method with other quantitative methods. The most suitable way for partial coalescence quantification was implied to be the fat particle size method, which would give results with a high degree of confidence if used in combination with a microscopic technique for the confirmation of partial coalescence as the main destabilization mechanism. Copyright © 2015 Elsevier B.V. All rights reserved.

Dynamics of partial differential equations

CERN Document Server

Wayne, C Eugene

2015-01-01

This book contains two review articles on the dynamics of partial differential equations that deal with closely related topics but can be read independently. Wayne reviews recent results on the global dynamics of the two-dimensional Navier-Stokes equations. This system exhibits stable vortex solutions: the topic of Wayne's contribution is how solutions that start from arbitrary initial conditions evolve towards stable vortices. Weinstein considers the dynamics of localized states in nonlinear Schrodinger and Gross-Pitaevskii equations that describe many optical and quantum systems. In this contribution, Weinstein reviews recent bifurcations results of solitary waves, their linear and nonlinear stability properties, and results about radiation damping where waves lose energy through radiation.   The articles, written independently, are combined into one volume to showcase the tools of dynamical systems theory at work in explaining qualitative phenomena associated with two classes of partial differential equ...

Radioisotopic neutron transmission spectrometry: Quantitative analysis by using partial least-squares method

International Nuclear Information System (INIS)

Kim, Jong-Yun; Choi, Yong Suk; Park, Yong Joon; Jung, Sung-Hee

2009-01-01

Neutron spectrometry, based on the scattering of high energy fast neutrons from a radioisotope and slowing-down by the light hydrogen atoms, is a useful technique for non-destructive, quantitative measurement of hydrogen content because it has a large measuring volume, and is not affected by temperature, pressure, pH value and color. The most common choice for radioisotope neutron source is 252 Cf or 241 Am-Be. In this study, 252 Cf with a neutron flux of 6.3x10 6 n/s has been used as an attractive neutron source because of its high flux neutron and weak radioactivity. Pulse-height neutron spectra have been obtained by using in-house built radioisotopic neutron spectrometric system equipped with 3 He detector and multi-channel analyzer, including a neutron shield. As a preliminary study, polyethylene block (density of ∼0.947 g/cc and area of 40 cmx25 cm) was used for the determination of hydrogen content by using multivariate calibration models, depending on the thickness of the block. Compared with the results obtained from a simple linear calibration model, partial least-squares regression (PLSR) method offered a better performance in a quantitative data analysis. It also revealed that the PLSR method in a neutron spectrometric system can be promising in the real-time, online monitoring of the powder process to determine the content of any type of molecules containing hydrogen nuclei.

The Effect of Dose-Volume Parameters and Interfraction Interval on Cosmetic Outcome and Toxicity After 3-Dimensional Conformal Accelerated Partial Breast Irradiation

International Nuclear Information System (INIS)

Leonard, Kara Lynne; Hepel, Jaroslaw T.; Hiatt, Jessica R.; Dipetrillo, Thomas A.; Price, Lori Lyn; Wazer, David E.

2013-01-01

Purpose: To evaluate dose-volume parameters and the interfraction interval (IFI) as they relate to cosmetic outcome and normal tissue effects of 3-dimensional conformal radiation therapy (3D-CRT) for accelerated partial breast irradiation (APBI). Methods and Materials: Eighty patients were treated by the use of 3D-CRT to deliver APBI at our institutions from 2003-2010 in strict accordance with the specified dose-volume constraints outlined in the National Surgical Adjuvant Breast and Bowel Project B39/Radiation Therapy Oncology Group 0413 (NSABP-B39/RTOG 0413) protocol. The prescribed dose was 38.5 Gy in 10 fractions delivered twice daily. Patients underwent follow-up with assessment for recurrence, late toxicity, and overall cosmetic outcome. Tests for association between toxicity endpoints and dosimetric parameters were performed with the chi-square test. Univariate logistic regression was used to evaluate the association of interfraction interval (IFI) with these outcomes. Results: At a median follow-up time of 32 months, grade 2-4 and grade 3-4 subcutaneous fibrosis occurred in 31% and 7.5% of patients, respectively. Subcutaneous fibrosis improved in 5 patients (6%) with extended follow-up. Fat necrosis developed in 11% of women, and cosmetic outcome was fair/poor in 19%. The relative volume of breast tissue receiving 5%, 20%, 50%, 80%, and 100% (V5-V100) of the prescribed dose was associated with risk of subcutaneous fibrosis, and the volume receiving 50%, 80%, and 100% (V50-V100) was associated with fair/poor cosmesis. The mean IFI was 6.9 hours, and the minimum IFI was 6.2 hours. The mean and minimum IFI values were not significantly associated with late toxicity. Conclusions: The incidence of moderate to severe late toxicity, particularly subcutaneous fibrosis and fat necrosis and resulting fair/poor cosmesis, remains high with continued follow-up. These toxicity endpoints are associated with several dose-volume parameters. Minimum and mean IFI values were

Relationship between partial and average atomic volumes of components in Au-Ni alloys%Au-Ni合金中组元的平均原子体积和偏摩尔体积的关系

Institute of Scientific and Technical Information of China (English)

谢佑卿

2011-01-01

在系统合金科学框架中建立有关无序合金的平均摩尔性质(体积和势能)的函数.通过对这些函数进行推导,可以得到平均摩尔体积函数、偏摩尔体积函数及派生出与成分相关的函数.在组元的偏摩尔性质和平均摩尔性质之间的普适方程、差分方程、在偏摩尔性质和平均摩尔性质之间不同参数的约束方程和普适的Gibbs-Duhem公式.可以证明从合金平均摩尔性质的不同函数计算的偏摩尔性质是相等的,但总体来说偏摩尔性质不等于给定组元的平均摩尔性质,即偏摩尔性质不能代表相应组元的摩尔性质.通过计算Au-Ni系中组元的偏摩尔体积和平均原子体积以及合金的平均原子体积,证明所建立的公式和函数的正确性.%In the framework of systematic science of alloys,the average molar property (volume and potential energy) functions of disordered alloys were established.From these functions,the average molar property functions,partial molar property functions,derivative functions with respect to composition,general equation of relationship between partial and average molar properties of components,difference equation and constraining equation of different values between partial and average molar properties,as well as general Gibbs-Duhem formula were derived.It was proved that the partial molar properties calculated from various combinative functions of average molar properties of alloys are equal,but in general,the partial molar properties are not equal to the average molar properties of a given component.This means that the partial molar properties cannot represent the corresponding properties of the component.All the equations and functions established in this work were proved to be correct by calculating the results of partial and average atomic volumes of components as well as average atomic volumes of alloys in the Au-Ni system.

Oxygen partial pressure sensor for gases

International Nuclear Information System (INIS)

Barbero, J.A.; Azcona, M.A.; Orce, A.

1997-01-01

Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10 -6 -1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs

Ultrasonographic gastric antral area and gastric contents volume in children.

Science.gov (United States)

Schmitz, Achim; Thomas, Schraner; Melanie, Fruehauf; Rabia, Liamlahi; Klaghofer, Richard; Weiss, Markus; Kellenberger, Christian

2012-02-01

Cross-sectional gastric antral area (GAA) measurements by ultrasonography (US) have been proposed for preoperative assessment of gastric volume in adults but not been validated in children. This study investigates whether in children gastric volumes can be predicted by US performed in different patient positions. Gastric fluid and air volumes were examined by magnetic resonance imaging before or up to 120 min after ingestion of 7 ml·kg(-1) diluted raspberry syrup in healthy volunteers who had fasted overnight. GAA was measured with US three times each in supine (SUP), elevated 45° degree supine (E45) and right decubital (RDC) position using imaging planes defined by vascular landmarks. Correlation coefficients (Pearson) between GAA and gastric volumes were calculated and Bland-Altman analysis performed. Sixteen children aged from 6.4 to 12.8 (9.2) years were included in 23 examinations: 6 after overnight fasting, 3 directly after, and 14 with a delay of 74 ± 35 min after fluid intake. GAA was 221 ± 116, 218 ± 112, and 347 ± 188 mm(2) for SUP, E45, and RDC position, respectively. The best correlation between body weight corrected total gastric/gastric fluid volume (TGV(w)/GFV(w)) with GAA was found for RDC position (R = 0.79; P < 0.01/R = 0.78; P < 0.01). Bias and precision of calculated and measured GFV(w) was 0 ± 2.8 ml·kg(-1). Correlations between GAA and TGV(w) or GFV(w) in children are best in the RDC position, but not sufficient to predict GFV(w) with a given GAA. Interpretation of isolated GAA values may be misleading. © 2011 Blackwell Publishing Ltd.

Finding related functional neuroimaging volumes

DEFF Research Database (Denmark)

Nielsen, Finn Årup; Hansen, Lars Kai

2004-01-01

We describe a content-based image retrieval technique for finding related functional neuroimaging experiments by voxelization of sets of stereotactic coordinates in Talairach space, comparing the volumes and reporting related volumes in a sorted list. Voxelization is accomplished by convolving ea...

Three-dimensional reconstruction volume: a novel method for volume measurement in kidney cancer.

Science.gov (United States)

Durso, Timothy A; Carnell, Jonathan; Turk, Thomas T; Gupta, Gopal N

2014-06-01

The role of volumetric estimation is becoming increasingly important in the staging, management, and prognostication of benign and cancerous conditions of the kidney. We evaluated the use of three-dimensional reconstruction volume (3DV) in determining renal parenchymal volumes (RPV) and renal tumor volumes (RTV). We compared 3DV with the currently available methods of volume assessment and determined its interuser reliability. RPV and RTV were assessed in 28 patients who underwent robot-assisted laparoscopic partial nephrectomy for kidney cancer. Patients with a preoperative creatinine level of kidney pre- and postsurgery overestimated 3D reconstruction volumes by 15% to 102% and 12% to 101%, respectively. In addition, volumes obtained from 3DV displayed high interuser reliability regardless of experience. 3DV provides a highly reliable way of assessing kidney volumes. Given that 3DV takes into account visible anatomy, the differences observed using previously published methods can be attributed to the failure of geometry to accurately approximate kidney or tumor shape. 3DV provides a more accurate, reproducible, and clinically useful tool for urologists looking to improve patient care using analysis related to volume.

Partial volume effect estimation and correction in the aortic vascular wall in PET imaging

International Nuclear Information System (INIS)

Burg, S; Le Guludec, D; Dupas, A; Stute, S; Dieudonné, A; Huet, P; Buvat, I

2013-01-01

We evaluated the impact of partial volume effect (PVE) in the assessment of arterial diseases with 18 FDG PET. An anthropomorphic digital phantom enabling the modeling of aorta related diseases like atherosclerosis and arteritis was used. Based on this phantom, we performed GATE Monte Carlo simulations to produce realistic PET images with a known organ segmentation and ground truth activity values. Images corresponding to 15 different activity-concentration ratios between the aortic wall and the blood and to 7 different wall thicknesses were generated. Using the PET images, we compared the theoretical wall-to-blood activity-concentration ratios (WBRs) with the measured WBRs obtained with five measurement methods: (1) measurement made by a physician (Expert), (2) automated measurement supposed to mimic the physician measurements (Max), (3) simple correction based on a recovery coefficient (Max-RC), (4) measurement based on an ideal VOI segmentation (Mean-VOI) and (5) measurement corrected for PVE using an ideal geometric transfer matrix (GTM) method. We found that Mean-VOI WBRs values were strongly affected by PVE. WBRs obtained by the physician measurement, by the Max method and by the Max-RC method were more accurate than WBRs obtained with the Mean-VOI approach. However Expert, Max and Max-RC WBRs strongly depended on the wall thickness. Only the GTM corrected WBRs did not depend on the wall thickness. Using the GTM method, we obtained more reproducible ratio values that could be compared across wall thickness. Yet, the feasibility of the implementation of a GTM-like method on real data remains to be studied. (paper)

Considerations and code for partial volume correcting [18F]-AV-1451 tau PET data

Directory of Open Access Journals (Sweden)

Suzanne L. Baker

2017-12-01

Full Text Available [18F]-AV-1451 is a leading tracer used with positron emission tomography (PET to quantify tau pathology. However, [18F]-AV-1451 shows “off target” or non-specific binding, which we define as binding of the tracer in unexpected areas unlikely to harbor aggregated tau based on autopsy literature [1]. Along with caudate, putamen, pallidum and thalamus non-specific binding [2,3], we have found binding in the superior portion of the cerebellar gray matter, leading us to use inferior cerebellar gray as the reference region. We also addressed binding in the posterior portion of the choroid plexus. PET signal unlikely to be associated with tau also occurs in skull, meninges and soft tissue (see e.g. [4]. We refer to [18F]-AV-1451 binding in the skull and meninges as extra-cortical hotspots (ECH and find them near lateral and medial orbitofrontal, lateral occipital, inferior and middle temporal, superior and inferior parietal, and inferior cerebellar gray matter. Lastly, the choroid plexus also shows non-specific binding that bleeds into hippocampus. We are providing the code (http://www.runmycode.org/companion/view/2798 used to create different regions of interest (ROIs that we then used to perform Partial Volume Correction (PVC using the Rousset geometric transfer matrix method (GTM, [5]. This method was used in the companion article, “Comparison of multiple tau-PET measures as biomarkers in aging and Alzheimer's Disease” ([6], DOI 10.1016/j.neuroimage.2017.05.058.

Extended Excluded Volume: Its Origin and Consequences

Czech Academy of Sciences Publication Activity Database

Nezbeda, Ivo; Rouha, M.

2013-01-01

Roč. 85, č. 1 (2013), s. 201-210 ISSN 0033-4545. [International Conference on Solution Chemistry (ICSC-32) /32./. La Grande Motte, 28.08.2011-02.09.2011] R&D Projects: GA AV ČR IAA400720802 Institutional support: RVO:67985858 Keywords : excluded volume * partial molar volume * primitive models Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.112, year: 2013

Physiological and biochemical principles underlying volume-targeted therapy--the "Lund concept".

Science.gov (United States)

Nordström, Carl-Henrik

2005-01-01

The optimal therapy of sustained increase in intracranial pressure (ICP) remains controversial. The volume-targeted therapy ("Lund concept") discussed in this article focuses on the physiological volume regulation of the intracranial compartments. The balance between effective transcapillary hydrostatic and osmotic pressures constitutes the driving force for transcapillary fluid exchange. The low permeability for sodium and chloride combined with the high crystalloid osmotic pressure (approximately 5700 mmHg) on both sides of the blood-brain barrier (BBB) counteracts fluid exchange across the intact BBB. Additionally, variations in systemic blood pressure generally are not transmitted to these capillaries because cerebral intracapillary hydrostatic pressure (and blood flow) is physio-logically tightly autoregulated. Under pathophysiological conditions, the BBB may be partially disrupted. Transcapillary water exchange is then determined by the differences in hydrostatic and colloid osmotic pressure between the intra- and extracapillary compartments. Pressure autoregulation of cerebral blood flow is likely to be impaired in these conditions. A high cerebral perfusion pressure accordingly increases intracapillary hydrostatic pressure and leads to increased intracerebral water content and an increase in ICP. The volume-targeted "Lund concept" has been evaluated in experimental and clinical studies to examine the physiological and biochemical (utilizing intracerebral microdialysis) effects, and the clinical experiences have been favorable.

Influence of hydrostatic pressure on dynamics and spatial distribution of protein partial molar volume: time-resolved surficial Kirkwood-Buff approach.

Science.gov (United States)

Yu, Isseki; Tasaki, Tomohiro; Nakada, Kyoko; Nagaoka, Masataka

2010-09-30

The influence of hydrostatic pressure on the partial molar volume (PMV) of the protein apomyoglobin (AMb) was investigated by all-atom molecular dynamics (MD) simulations. Using the time-resolved Kirkwood-Buff (KB) approach, the dynamic behavior of the PMV was identified. The simulated time average value of the PMV and its reduction by 3000 bar pressurization correlated with experimental data. In addition, with the aid of the surficial KB integral method, we obtained the spatial distributions of the components of PMV to elucidate the detailed mechanism of the PMV reduction. New R-dependent PMV profiles identified the regions that increase or decrease the PMV under the high pressure condition. The results indicate that besides the hydration in the vicinity of the protein surface, the outer space of the first hydration layer also significantly influences the total PMV change. These results provide a direct and detailed picture of pressure induced PMV reduction.

Factors influencing liver and spleen volume changes after donor hepatectomy for living donor liver transplantation

Energy Technology Data Exchange (ETDEWEB)

Bae, Ji Hee; Ryeom, Hunku; Song, Jung Hup [Kyungpook National University Hospital, Daegu (Korea, Republic of)

2013-11-15

To define the changes in liver and spleen volumes in the early postoperative period after partial liver donation for living-donor liver transplantation (LDLT) and to determine factors that influence liver and spleen volume changes. 27 donors who underwent partial hepatectomy for LDLT were included in this study. The rates of liver and spleen volume change, measured with CT volumetry, were correlated with several factors. The analyzed factors included the indocyanine green (ICG) retention rate at 15 minutes after ICG administration, preoperative platelet count, preoperative liver and splenic volumes, resected liver volume, resected-to-whole liver volume ratio (LV{sub R}/LV{sub W}), resected liver volume to the sum of whole liver and spleen volume ratio [LV{sub R}/(LV{sub W} + SV{sub 0})], and pre and post hepatectomy portal venous pressures. In all hepatectomy donors, the volumes of the remnant liver and spleen were increased (increased rates, 59.5 ± 50.5%, 47.9 ± 22.6%). The increment rate of the remnant liver volume revealed a positive correlation with LV{sub R}/LV{sub W} (r = 0.759, p < 0.01). The other analyzed factors showed no correlation with changes in liver and spleen volumes. The spleen and remnant liver volumes were increased at CT volumetry performed 2 weeks after partial liver donation. Among the various analyzed factors, LV{sub R}/LV{sub W} influences the increment rate of the remnant liver volume.

Two-phase anaerobic digestion of partially acidified sewage sludge: a pilot plant study for safe sludge disposal in developing countries.

Science.gov (United States)

Passio, Luca; Rizzoa, Luigi; Fuchs, Stephan

2012-09-01

The unsafe disposal of wastewater and sludge in different areas of developing countries results in significant environmental pollution, particularly for groundwater, thus increasing the risk of waterborne diseases spreading. In this work, a two-phase anaerobic digestion process for post-treatment of partially acidified sewage sludge was investigated to evaluate its feasibility as a safe sludge disposal system. Pilot tests showed that an effective sludge stabilization can be achieved (total volatile solids content <65%, organic acid concentration <200 mg/L at flow rate = 50 L/d and hydraulic residence time = 18 d) as well as a relative low faecal coliform density (<1000 most probable number per g total solids), showing that land application of the sludge without restrictions is possible according to US Environmental Protection Agency criteria for safe sludge disposal. A biogas production as high as 390 L/d with a 60% methane content by volume was achieved, showing that energy production from biogas may be achieved as well.

The Partial Molar Volume and Compressibility of the FeO Component in Model Basalts (Mixed CaAl2Si2O8-CaMgSi2O6-CaFeSi2O6 Liquids) at 0 GPa: evidence of Fe2+ in 6-fold coordination

Science.gov (United States)

Guo, X.; Lange, R. A.; Ai, Y.

2010-12-01

FeO is an important component in magmatic liquids and yet its partial molar volume at one bar is not as well known as that for Fe2O3 because of the difficulty of performing double-bob density measurements under reducing conditions. Moreover, there is growing evidence from spectroscopic studies that Fe2+ occurs in 4, 5, and 6-fold coordination in silicate melts, and it is expected that the partial molar volume and compressibility of the FeO component will vary accordingly. We have conducted both density and relaxed sound speed measurements on four liquids in the An-Di-Hd (CaAl2Si2O8-CaMgSi2O6-CaFeSi2O6) system: (1) Di-Hd (50:50), (2) An-Hd (50:50), (3) An-Di-Hd (33:33:33) and (4) Hd (100). Densities were measured between 1573 and 1838 K at one bar with the double-bob Archimedean method using molybdenum bobs and crucibles in a reducing gas (1%CO-99%Ar) environment. The sound speeds were measured under similar conditions with a frequency-sweep acoustic interferometer, and used to calculate isothermal compressibility. All the density data for the three multi-component (model basalt) liquids were combined with density data on SiO2-Al2O3-CaO-MgO-K2O-Na2O liquids (Lange, 1997) in a fit to a linear volume equation; the results lead to a partial molar volume (±1σ) for FeO =11.7 ± 0.3(±1σ) cm3/mol at 1723 K. This value is similar to that for crystalline FeO at 298 K (halite structure; 12.06 cm3/mol), which suggests an average Fe2+ coordination of ~6 in these model basalt compositions. In contrast, the fitted partial molar volume of FeO in pure hedenbergite liquid is 14.6 ± 0.3 at 1723 K, which is consistent with an average Fe2+ coordination of 4.3 derived from EXAFS spectroscopy (Rossano, 2000). Similarly, all the compressibility data for the three multi-component liquids were combined with compressibility data on SiO2-Al2O3-CaO-MgO liquids (Ai and Lange, 2008) in a fit to an ideal mixing model for melt compressibility; the results lead to a partial molar

DEVICE FOR CONTROL OF OXYGEN PARTIAL PRESSURE

Science.gov (United States)

Bradner, H.; Gordon, H.S.

1957-12-24

A device is described that can sense changes in oxygen partial pressure and cause a corresponding mechanical displacement sufficient to actuate meters, valves and similar devices. A piston and cylinder arrangement contains a charge of crystalline metal chelate pellets which have the peculiar property of responding to variations in the oxygen content of the ambient atmosphere by undergoing a change in dimension. A lever system amplifies the relative displacement of the piston in the cylinder, and actuates the controlled valving device. This partial pressure oxygen sensing device is useful in controlled chemical reactions or in respiratory devices such as the oxygen demand meters for high altitude aircraft.

How does knowledge of three-dimensional excision margins following breast conservation surgery impact upon clinical target volume definition for partial-breast radiotherapy?

International Nuclear Information System (INIS)

Kirby, Anna M.; Evans, Philip M.; Nerurkar, Ashutosh Y.; Desai, Saral S.; Krupa, Jaroslaw; Devalia, Haresh; Rovere, Guidubaldo Querci della; Harris, Emma J.; Kyriakidou, Julia; Yarnold, John R.

2010-01-01

Background and purpose: To compare partial-breast clinical target volumes generated using a standard 15 mm margin (CTV standard ) with those generated using three-dimensional surgical excision margins (CTV tailored30 ) in women who have undergone wide local excision (WLE) for breast cancer. Material and methods: Thirty-five women underwent WLE with placement of clips in the anterior, deep and coronal excision cavity walls. Distances from tumour to each of six margins were measured microscopically. Tumour bed was defined on kV-CT images using clips. CTV standard was generated by adding a uniform three-dimensional 15 mm margin, and CTV tailored30 was generated by adding 30 mm minus the excision margin in three-dimensions. Concordance between CTV standard and CTV tailored30 was quantified using conformity (CoI), geographical-miss (GMI) and normal-tissue (NTI) indices. An external-beam partial-breast irradiation (PBI) plan was generated to cover 95% of CTV standard with the 95% isodose. Percentage-volume coverage of CTV tailored30 by the 95% isodose was measured. Results: Median (range) coronal, superficial and deep excision margins were 15.0 (0.5-76.0) mm, 4.0 (0.0-60.0) mm and 4.0 (0.5-35.0) mm, respectively. Median CoI, GMI and NTI were 0.62, 0.16 and 0.20, respectively. Median coverage of CTV tailored30 by the PBI-plan was 97.7% (range 84.9-100.0%). CTV tailored30 was inadequately covered by the 95% isodose in 4/29 cases. In three cases, the excision margin in the direction of inadequate coverage was ≤2 mm. Conclusions: CTVs based on 3D excision margin data are discordant with those defined using a standard uniform 15 mm TB-CTV margin. In women with narrow excision margins, the standard TB-CTV margin could result in a geographical miss. Therefore, wider TB-CTV margins should be considered where re-excision does not occur.

18F-fluorocholine PET-guided target volume delineation techniques for partial prostate re-irradiation in local recurrent prostate cancer

International Nuclear Information System (INIS)

Wang Hui; Vees, Hansjoerg; Miralbell, Raymond; Wissmeyer, Michael; Steiner, Charles; Ratib, Osman; Senthamizhchelvan, Srinivasan; Zaidi, Habib

2009-01-01

Background and purpose: We evaluate the contribution of 18 F-choline PET/CT in the delineation of gross tumour volume (GTV) in local recurrent prostate cancer after initial irradiation using various PET image segmentation techniques. Materials and methods: Seventeen patients with local-only recurrent prostate cancer (median = 5.7 years) after initial irradiation were included in the study. Rebiopsies were performed in 10 patients that confirmed the local recurrence. Following injection of 300 MBq of 18 F-fluorocholine, dynamic PET frames (3 min each) were reconstructed from the list-mode acquisition. Five PET image segmentation techniques were used to delineate the 18 F-choline-based GTVs. These included manual delineation of contours (GTV man ) by two teams consisting of a radiation oncologist and a nuclear medicine physician each, a fixed threshold of 40% and 50% of the maximum signal intensity (GTV 40% and GTV 50% ), signal-to-background ratio-based adaptive thresholding (GTV SBR ), and a region growing (GTV RG ) algorithm. Geographic mismatches between the GTVs were also assessed using overlap analysis. Results: Inter-observer variability for manual delineation of GTVs was high but not statistically significant (p = 0.459). In addition, the volumes and shapes of GTVs delineated using semi-automated techniques were significantly higher than those of GTVs defined manually. Conclusions: Semi-automated segmentation techniques for 18 F-choline PET-guided GTV delineation resulted in substantially higher GTVs compared to manual delineation and might replace the latter for determination of recurrent prostate cancer for partial prostate re-irradiation. The selection of the most appropriate segmentation algorithm still needs to be determined.

18F-fluorocholine PET-guided target volume delineation techniques for partial prostate re-irradiation in local recurrent prostate cancer.

Science.gov (United States)

Wang, Hui; Vees, Hansjörg; Miralbell, Raymond; Wissmeyer, Michael; Steiner, Charles; Ratib, Osman; Senthamizhchelvan, Srinivasan; Zaidi, Habib

2009-11-01

We evaluate the contribution of (18)F-choline PET/CT in the delineation of gross tumour volume (GTV) in local recurrent prostate cancer after initial irradiation using various PET image segmentation techniques. Seventeen patients with local-only recurrent prostate cancer (median=5.7 years) after initial irradiation were included in the study. Rebiopsies were performed in 10 patients that confirmed the local recurrence. Following injection of 300 MBq of (18)F-fluorocholine, dynamic PET frames (3 min each) were reconstructed from the list-mode acquisition. Five PET image segmentation techniques were used to delineate the (18)F-choline-based GTVs. These included manual delineation of contours (GTV(man)) by two teams consisting of a radiation oncologist and a nuclear medicine physician each, a fixed threshold of 40% and 50% of the maximum signal intensity (GTV(40%) and GTV(50%)), signal-to-background ratio-based adaptive thresholding (GTV(SBR)), and a region growing (GTV(RG)) algorithm. Geographic mismatches between the GTVs were also assessed using overlap analysis. Inter-observer variability for manual delineation of GTVs was high but not statistically significant (p=0.459). In addition, the volumes and shapes of GTVs delineated using semi-automated techniques were significantly higher than those of GTVs defined manually. Semi-automated segmentation techniques for (18)F-choline PET-guided GTV delineation resulted in substantially higher GTVs compared to manual delineation and might replace the latter for determination of recurrent prostate cancer for partial prostate re-irradiation. The selection of the most appropriate segmentation algorithm still needs to be determined.

Oxygen partial pressure sensor for gases

Energy Technology Data Exchange (ETDEWEB)

Barbero, J.A.; Azcona, M.A.; Orce, A. [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

1997-10-01

Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10{sup -6}-1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs.

Partial microwave-assisted wet digestion of animal tissue using a baby-bottle sterilizer for analyte determination by inductively coupled plasma optical emission spectrometry

International Nuclear Information System (INIS)

Matos, Wladiana O.; Menezes, Eveline A.; Gonzalez, Mario H.; Costa, Leticia M.; Trevizan, Lilian C.; Nogueira, Ana Rita A.

2009-01-01

A procedure for partial digestion of bovine tissue is proposed using polytetrafluoroethylene (PTFE) micro-vessels inside a baby-bottle sterilizer under microwave radiation for multi-element determination by inductively coupled plasma optical emission spectrometry (ICP OES). Samples were directly weighed in laboratory-made polytetrafluoroethylene vessels. Nitric acid and hydrogen peroxide were added to the uncovered vessels, which were positioned inside the baby-bottle sterilizer, containing 500 mL of water. The hydrogen peroxide volume was fixed at 100 μL. The system was placed in a domestic microwave oven and partial digestion was carried out for the determination of Ca, Cu, Fe, Mg, Mn and Zn by inductively coupled plasma optical emission spectrometry. The single-vessel approach was used in the entire procedure, to minimize contamination in trace analysis. Better recoveries and lower residual carbon content (RCC) levels were obtained under the conditions established through a 2 4-1 fractional factorial design: 650 W microwave power, 7 min digestion time, 50 μL nitric acid and 50 mg sample mass. The digestion efficiency was ascertained according to the residual carbon content determined by inductively coupled plasma optical emission spectrometry. The accuracy of the proposed procedure was checked against two certified reference materials.

Regulated phosphorylation of the K-Cl cotransporter KCC3 is a molecular switch of intracellular potassium content and cell volume homeostasis.

Science.gov (United States)

Adragna, Norma C; Ravilla, Nagendra B; Lauf, Peter K; Begum, Gulnaz; Khanna, Arjun R; Sun, Dandan; Kahle, Kristopher T

2015-01-01

The defense of cell volume against excessive shrinkage or swelling is a requirement for cell function and organismal survival. Cell swelling triggers a coordinated homeostatic response termed regulatory volume decrease (RVD), resulting in K(+) and Cl(-) efflux via activation of K(+) channels, volume-regulated anion channels (VRACs), and the K(+)-Cl(-) cotransporters, including KCC3. Here, we show genetic alanine (Ala) substitution at threonines (Thr) 991 and 1048 in the KCC3a isoform carboxyl-terminus, preventing inhibitory phosphorylation at these sites, not only significantly up-regulates KCC3a activity up to 25-fold in normally inhibitory isotonic conditions, but is also accompanied by reversal of activity of the related bumetanide-sensitive Na(+)-K(+)-2Cl(-) cotransporter isoform 1 (NKCC1). This results in a rapid (90%) reduction in intracellular K(+) content (Ki) via both Cl-dependent (KCC3a + NKCC1) and Cl-independent [DCPIB (VRAC inhibitor)-sensitive] pathways, which collectively renders cells less prone to acute swelling in hypotonic osmotic stress. Together, these data demonstrate the phosphorylation state of Thr991/Thr1048 in KCC3a encodes a potent switch of transporter activity, Ki homeostasis, and cell volume regulation, and reveal novel observations into the functional interaction among ion transport molecules involved in RVD.

Quantification accuracy and partial volume effect in dependence of the attenuation correction of a state-of-the-art small animal PET scanner

International Nuclear Information System (INIS)

Mannheim, Julia G; Judenhofer, Martin S; Schmid, Andreas; Pichler, Bernd J; Tillmanns, Julia; Stiller, Detlef; Sossi, Vesna

2012-01-01

Quantification accuracy and partial volume effect (PVE) of the Siemens Inveon PET scanner were evaluated. The influence of transmission source activities (40 and 160 MBq) on the quantification accuracy and the PVE were determined. Dynamic range, object size and PVE for different sphere sizes, contrast ratios and positions in the field of view (FOV) were evaluated. The acquired data were reconstructed using different algorithms and correction methods. The activity level of the transmission source and the total emission activity in the FOV strongly influenced the attenuation maps. Reconstruction algorithms, correction methods, object size and location within the FOV had a strong influence on the PVE in all configurations. All evaluated parameters potentially influence the quantification accuracy. Hence, all protocols should be kept constant during a study to allow a comparison between different scans. (paper)

Abstraction of complex concepts with a refined partial-area taxonomy of SNOMED

Science.gov (United States)

Wang, Yue; Halper, Michael; Wei, Duo; Perl, Yehoshua; Geller, James

2012-01-01

An algorithmically-derived abstraction network, called the partial-area taxonomy, for a SNOMED hierarchy has led to the identification of concepts considered complex. The designation “complex” is arrived at automatically on the basis of structural analyses of overlap among the constituent concept groups of the partial-area taxonomy. Such complex concepts, called overlapping concepts, constitute a tangled portion of a hierarchy and can be obstacles to users trying to gain an understanding of the hierarchy’s content. A new methodology for partitioning the entire collection of overlapping concepts into singly-rooted groups, that are more manageable to work with and comprehend, is presented. Different kinds of overlapping concepts with varying degrees of complexity are identified. This leads to an abstract model of the overlapping concepts called the disjoint partial-area taxonomy, which serves as a vehicle for enhanced, high-level display. The methodology is demonstrated with an application to SNOMED’s Specimen hierarchy. Overall, the resulting disjoint partial-area taxonomy offers a refined view of the hierarchy’s structural organization and conceptual content that can aid users, such as maintenance personnel, working with SNOMED. The utility of the disjoint partial-area taxonomy as the basis for a SNOMED auditing regimen is presented in a companion paper. PMID:21878396

Monitoring Heavy Metal Contents with Sphagnum Junghuhnianum Moss Bags in Relation to Traffic Volume in Wuxi, China.

Science.gov (United States)

Hu, Rong; Yan, Yun; Zhou, Xiaoli; Wang, Yanan; Fang, Yanming

2018-02-22

Despite its small size, a moss bag can reveal the different temporal and spatial deposition patterns of pollutants at a particular site; therefore, researchers can use moss bags to determine pollution sources and to put forward strategies for pollution control. Although the use of moss bags to monitor atmospheric pollution has been widely reported in Europe, there are few such empirical studies in China. Thus, in this study, bags containing the moss Sphagnum junghuhnianum were used to assess the concentrations of heavy metals (chromium (Cr), copper (Cu), lead (Pb), vanadium (V), and zinc (Zn)) at five sampling sites (four roads and a forest park) during the summer and winter of 2012. According to the relative accumulation factor (RAF) and contamination factor (CF) results, pollution in winter was heavier than that in summer, and Cr was found to be the most contaminating, having the highest mean CF. There was a significant positive correlation ( p heavy metals (Cr, Cu, and V) in winter, whereas a significant positive correlation ( p heavy metal elements (Cr, Pb, V, and Zn) in summer, indicating a close relationship between heavy metal contents and traffic volume. Although there was substantial variation in the concentrations of the five heavy metals in the moss bags, significant correlations between heavy metals suggested that the contaminants originated from a common source, namely vehicle emissions. The results demonstrated that the four roads were subject to different degrees of pollution depending on the volume of traffic using each road. Therefore, the results of this study suggest that traffic volume is a major reason for heavy metal pollution.

Standard Test Methods for Constituent Content of Composite Materials

CERN Document Server

American Society for Testing and Materials. Philadelphia

2009-01-01

1.1 These test methods determine the constituent content of composite materials by one of two approaches. Method I physically removes the matrix by digestion or ignition by one of seven procedures, leaving the reinforcement essentially unaffected and thus allowing calculation of reinforcement or matrix content (by weight or volume) as well as percent void volume. Method II, applicable only to laminate materials of known fiber areal weight, calculates reinforcement or matrix content (by weight or volume), and the cured ply thickness, based on the measured thickness of the laminate. Method II is not applicable to the measurement of void volume. 1.1.1 These test methods are primarily intended for two-part composite material systems. However, special provisions can be made to extend these test methods to filled material systems with more than two constituents, though not all test results can be determined in every case. 1.1.2 The procedures contained within have been designed to be particularly effective for ce...

An analysis of the nucleon spectrum from lattice partially-quenched QCD.

Energy Technology Data Exchange (ETDEWEB)

Armour, W.; Allton, C. R.; Leinweber, D. B.; Thomas, A. W.; Young, R. D.; Physics; Swansea Univ.; Univ. of Adelaide; Coll. of William and Mary

2010-09-01

The chiral extrapolation of the nucleon mass, M{sub n}, is investigated using data coming from 2-flavour partially-quenched lattice simulations. A large sample of lattice results from the CP-PACS Collaboration is analysed using the leading one-loop corrections, with explicit corrections for finite lattice spacing artifacts. The extrapolation is studied using finite-range regularised chiral perturbation theory. The analysis also provides a quantitative estimate of the leading finite volume corrections. It is found that the discretisation, finite volume and partial quenching effects can all be very well described in this framework, producing an extrapolated value of Mn in agreement with experiment. Furthermore, determinations of the low energy constants of the nucleon mass's chiral expansion are in agreement with previous methods, but with significantly reduced errors. This procedure is also compared with extrapolations based on polynomial forms, where the results are less encouraging.

An analysis of the nucleon spectrum from lattice partially-quenched QCD

Energy Technology Data Exchange (ETDEWEB)

Armour, W. [Department of Physics, Swansea University, Swansea SA2 8PP, Wales (United Kingdom); Allton, C.R., E-mail: c.allton@swan.ac.u [Department of Physics, Swansea University, Swansea SA2 8PP, Wales (United Kingdom); Leinweber, D.B. [Special Research Centre for the Subatomic Structure of Matter (CSSM), School of Chemistry and Physics, University of Adelaide, 5005 (Australia); Thomas, A.W. [Jefferson Lab, 12000 Jefferson Ave., Newport News, VA 23606 (United States); College of William and Mary, Williamsburg, VA 23187 (United States); Young, R.D. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2010-09-01

The chiral extrapolation of the nucleon mass, M{sub n}, is investigated using data coming from 2-flavour partially-quenched lattice simulations. A large sample of lattice results from the CP-PACS Collaboration is analysed using the leading one-loop corrections, with explicit corrections for finite lattice spacing artifacts. The extrapolation is studied using finite-range regularised chiral perturbation theory. The analysis also provides a quantitative estimate of the leading finite volume corrections. It is found that the discretisation, finite volume and partial quenching effects can all be very well described in this framework, producing an extrapolated value of M{sub n} in agreement with experiment. Furthermore, determinations of the low energy constants of the nucleon mass's chiral expansion are in agreement with previous methods, but with significantly reduced errors. This procedure is also compared with extrapolations based on polynomial forms, where the results are less encouraging.

293.15 K到333.15 K温度下一些氨基酸及其相应基团水溶液中的偏摩尔体积研究%Studies on Partial Molar Volumes of Some Amino Acids and Their Groups in Aqueous Solutions from 293.15 K to 333.15 K

Institute of Scientific and Technical Information of China (English)

赵长伟; 马沛生; 夏淑倩

2004-01-01

Densities of aqueous solutions of eight amino acids, glycine, L-alanine, L-valine, L-isoleucine, L-serine,L-threonine, L-arginine and L-phenylalanine, are measured as a function of amino acid concentration from 293.15 K to 333.15K. These data are used to calculate the apparent molar volume V and infinite dilution apparent molar volume V0 (partial molar volume). Data of five amino acids are used to correlate partial molar volume V0 using group contribution method to estimate the contributions of the zwitterionic end groups (NH3+,COO-) and CH2group, OH group, CNHNHNH2 group and C6H5(phenyl) group of amino acids. The results show that V0 values for all kinds of groups of amino acids studied increase with increase of temperature except those for CH2 group,which are almost constant within the studied temperature range. Data of other amino acids, L-valine, L-isoleucine and L-threonine, are chosen for comparison with the predicted partial molar volume V0 using the group additivity parameters obtained. The results confirm that this group additivity method has excellent predictive utility.

Plasma volume changes during hypoglycaemia: the effect of arterial blood sampling

DEFF Research Database (Denmark)

Hilsted, J; Bendtsen, Flemming; Christensen, N J

1990-01-01

To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... hypoglycaemia. The magnitude of the changes in arterial and venous blood were not significantly different. These results indicate that the above changes in blood volume and composition are whole-body phenomena: furthermore, the major part of the changes are likely to occur in tissues other than upper extremity...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

Flow rate measurement in a volume

Energy Technology Data Exchange (ETDEWEB)

Galvez, Cristhian

2018-04-17

A system for measuring flow rate within a volume includes one or more transmission devices that transmit one or more signals through fluid contained within the volume. The volume may be bounded, at least in part, by an outer structure and by an object at least partially contained within the outer structure. A transmission device located at a first location of the outer structure transmits a first signal to a second location of the outer structure. A second signal is transmitted through the fluid from the second location to a third location of the outer structure. The flow rate of the fluid within the volume may be determined based, at least in part, on the time of flight of both the first signal and the second signal.

Finite Volumes for Complex Applications VII

CERN Document Server

Ohlberger, Mario; Rohde, Christian

2014-01-01

The methods considered in the 7th conference on "Finite Volumes for Complex Applications" (Berlin, June 2014) have properties which offer distinct advantages for a number of applications. The second volume of the proceedings covers reviewed contributions reporting successful applications in the fields of fluid dynamics, magnetohydrodynamics, structural analysis, nuclear physics, semiconductor theory and other topics. The finite volume method in its various forms is a space discretization technique for partial differential equations based on the fundamental physical principle of conservation. Recent decades have brought significant success in the theoretical understanding of the method. Many finite volume methods preserve further qualitative or asymptotic properties, including maximum principles, dissipativity, monotone decay of free energy, and asymptotic stability. Due to these properties, finite volume methods belong to the wider class of compatible discretization methods, which preserve qualitative propert...

Effect of copolymer latexes on physicomechanical properties of mortar containing high volume fly ash as a replacement material of cement.

Science.gov (United States)

Negim, El-Sayed; Kozhamzharova, Latipa; Gulzhakhan, Yeligbayeva; Khatib, Jamal; Bekbayeva, Lyazzat; Williams, Craig

2014-01-01

This paper investigates the physicomechanical properties of mortar containing high volume of fly ash (FA) as partial replacement of cement in presence of copolymer latexes. Portland cement (PC) was partially replaced with 0, 10, 20, 30 50, and 60% FA. Copolymer latexes were used based on 2-hydroxyethyl acrylate (2-HEA) and 2-hydroxymethylacrylate (2-HEMA). Testing included workability, setting time, absorption, chemically combined water content, compressive strength, and scanning electron microscopy (SEM). The addition of FA to mortar as replacement of PC affected the physicomechanical properties of mortar. As the content of FA in the concrete increased, the setting times (initial and final) were elongated. The results obtained at 28 days of curing indicate that the maximum properties of mortar occur at around 30% FA. Beyond 30% FA the properties of mortar reduce and at 60% FA the properties of mortar are lower than those of the reference mortar without FA. However, the addition of polymer latexes into mortar containing FA improved most of the physicomechanical properties of mortar at all curing times. Compressive strength, combined water, and workability of mortar containing FA premixed with latexes are higher than those of mortar containing FA without latexes.

Crowdfunding Through a Partial Organization Lens

DEFF Research Database (Denmark)

Nielsen, Kristian Roed

2018-01-01

Crowdfunding has become a rapidly growing source of alternative financing for a wide range of products and service ideas. The crowdfunding process itself necessitates the successful interaction between a number of actors including the central organizing platform, a number of content providing...... campaigns, and a large diverse group of funders. By utilizing the literature on complete and partial organizations and rejecting the commonly applied organizational molds to describe the process, this paper proposes that crowdfunding is organized and enabled as a fluid and co-dependent interaction between...... the various actors. The concept of partial organizations and its emphasis on key organizational decisions reveal that crowdfunding may be conceived of as a “co-dependent organization” in which the relationship of the involved actors is so interdependent that the crowdfunding process can neither be maintained...

Hunger and thirst numeric rating scales are not valid estimates for gastric content volumes: a prospective investigation in healthy children.

Science.gov (United States)

Buehrer, Sabin; Hanke, Ursula; Klaghofer, Richard; Fruehauf, Melanie; Weiss, Markus; Schmitz, Achim

2014-03-01

A rating scale for thirst and hunger was evaluated as a noninvasive, simple and commonly available tool to estimate preanesthetic gastric volume, a surrogate parameter for the risk of perioperative pulmonary aspiration, in healthy volunteer school age children. Numeric scales with scores from 0 to 10 combined with smileys to rate thirst and hunger were analyzed and compared with residual gastric volumes as measured by magnetic resonance imaging and fasting times in three settings: before and for 2 h after drinking clear fluid (group A, 7 ml/kg), before and for 4 vs 6 h after a light breakfast followed by clear fluid (7 ml/kg) after 2 vs 4 h (crossover, group B), and before and for 1 h after drinking clear fluid (crossover, group C, 7 vs 3 ml/kg). In 30 children aged 6.4-12.8 (median 9.8) years, participating on 1-5 (median two) study days, 496 sets of scores and gastric volumes were determined. Large inter- and intra-individual variations were seen at baseline and in response to fluid and food intake. Significant correlations were found between hunger and thirst ratings in all groups, with children generally being more hungry than thirsty. Correlations between scores and duration of fasting or gastric residual volumes were poor to moderate. Receiver operating characteristic (ROC) analysis revealed that thirst and hunger rating scales cannot predict gastric content. Hunger and thirst scores vary considerably inter- and intra-individually and cannot predict gastric volume, nor do they correlate with fasting times in school age children. © 2013 John Wiley & Sons Ltd.

A Virtual Reality System for PTCD Simulation Using Direct Visuo-Haptic Rendering of Partially Segmented Image Data.

Science.gov (United States)

Fortmeier, Dirk; Mastmeyer, Andre; Schröder, Julian; Handels, Heinz

2016-01-01

This study presents a new visuo-haptic virtual reality (VR) training and planning system for percutaneous transhepatic cholangio-drainage (PTCD) based on partially segmented virtual patient models. We only use partially segmented image data instead of a full segmentation and circumvent the necessity of surface or volume mesh models. Haptic interaction with the virtual patient during virtual palpation, ultrasound probing and needle insertion is provided. Furthermore, the VR simulator includes X-ray and ultrasound simulation for image-guided training. The visualization techniques are GPU-accelerated by implementation in Cuda and include real-time volume deformations computed on the grid of the image data. Computation on the image grid enables straightforward integration of the deformed image data into the visualization components. To provide shorter rendering times, the performance of the volume deformation algorithm is improved by a multigrid approach. To evaluate the VR training system, a user evaluation has been performed and deformation algorithms are analyzed in terms of convergence speed with respect to a fully converged solution. The user evaluation shows positive results with increased user confidence after a training session. It is shown that using partially segmented patient data and direct volume rendering is suitable for the simulation of needle insertion procedures such as PTCD.

Hyperbolic partial differential equations populations, reactors, tides and waves theory and applications

CERN Document Server

Witten, Matthew

1983-01-01

Hyperbolic Partial Differential Equations, Volume 1: Population, Reactors, Tides and Waves: Theory and Applications covers three general areas of hyperbolic partial differential equation applications. These areas include problems related to the McKendrick/Von Foerster population equations, other hyperbolic form equations, and the numerical solution.This text is composed of 15 chapters and begins with surveys of age specific population interactions, populations models of diffusion, nonlinear age dependent population growth with harvesting, local and global stability for the nonlinear renewal eq

APPLICATION OF ESSENTIAL OILS EXTRACTED FROM PEELS OF ORANGES AS A PARTIAL SUBSTITUTE OF FLOCCULANT

Directory of Open Access Journals (Sweden)

Anna Kowalczyk

2016-05-01

Full Text Available The study attempts to determine the optimum conditions of the process of mechanical dewatering of municipal sewage sludge and reduction of odours emitted during this process. The process of dewatering of municipal sewage sludge was carried out using laboratory sedimentation centrifuge of MPW-350 type. Municipal sewage sludge stabilized during anaerobic digestion, taken from Wastewater Treatment Plant Jamno. The dewatering process was aided by cationic flocculant Praestol 855BS of real solution concentration 0.3% and essential oil from orange, which was extracted from orange peels in the process of steam distillation. Constant parameters of dewatering process were: pH, temperature, colour, texture, smell, water content and dry matter content. Independent variables of dewatering process were: centrifugation time (in the range 1–10 min, centrifugation speed (in the range 1000–3000 rotations/min and dose of mixture of flocculant Praestol 855BS (79% + essential oil of orange (21% in the range 0–48 ml/dm3. Water content in the sludge after the process, dry matter content in the effluent and the duration of the smell of oil in the sediment were determined. Studies showed that the essential oil from orange may be used as a partial substitute of flocculant Praestol 855BS in the process of centrifugal sedimentation. Essential oil of orange significantly reduces unpleasant odours which are emitted from sludge during mechanical dewatering. Simultaneous application of both reagents, ie. flocculant Praestol 855BS 79%, and essential oil of orange 21% of volume is recommended.

Numerical Methods for Partial Differential Equations

CERN Document Server

Guo, Ben-yu

1987-01-01

These Proceedings of the first Chinese Conference on Numerical Methods for Partial Differential Equations covers topics such as difference methods, finite element methods, spectral methods, splitting methods, parallel algorithm etc., their theoretical foundation and applications to engineering. Numerical methods both for boundary value problems of elliptic equations and for initial-boundary value problems of evolution equations, such as hyperbolic systems and parabolic equations, are involved. The 16 papers of this volume present recent or new unpublished results and provide a good overview of current research being done in this field in China.

Pozzolanic Activity Assessment of LUSI (LUmpur SIdoarjo) Mud in Semi High Volume Pozzolanic Mortar

Science.gov (United States)

Hardjito, Djwantoro; Antoni; Wibowo, Gunadi M.; Christianto, Danny

2012-01-01

LUSI mud obtained from the mud volcano in Sidoarjo, Indonesia, is a viable aluminosilicate material to be utilized as pozzolanic material. LUSI is an abbreviation of the local name of the mud, i.e., Lumpur Sidoarjo, meaning Sidoarjo mud. This paper reports the results of an investigation to assess the pozzolanic activity of LUSI mud, especially in semi high volume pozzolanic mortar. In this case, the amount of mud incorporated is between 30% to 40% of total cementitious material, by mass. The content of SiO2 in the mud is about 30%, whilst the total content of SiO2, Fe2O3 and Al2O3 is more than 70%. Particle size and degree of partial cement replacement by treated LUSI mud affect the compressive strength, the strength activity index (SAI), the rate of pozzolanic activity development, and the workability of mortar incorporating LUSI mud. Manufacturing semi high volume LUSI mud mortar, up to at least 40% cement replacement, is a possibility, especially with a smaller particle size of LUSI mud, less than 63 μm. The use of a larger percentage of cement replacement by LUSI mud does not show any adverse effect on the water demand, as the flow of the fresh mortar increased with the increase of percentage of LUSI mud usage.

Water resources data for California, water year 1980; Volume 1, Colorado River basin, Southern Great Basin from Mexican border to Mono Lake basin, and Pacific slope basins from Tijuana River to Santa Maria River

Science.gov (United States)

,

1981-01-01

Volume 1 of water resources data for the 1980 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lake and reservoirs; and water levels in wells. This report contains discharge records for 174 gaging stations; stage and contents for 18 lakes and reservoirs; water quality for 51 stations; water levels for 165 observation wells. Also included are 9 crest-stage partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

[Prediction of total nitrogen and alkali hydrolysable nitrogen content in loess using hyperspectral data based on correlation analysis and partial least squares regression].

Science.gov (United States)

Liu, Xiu-ying; Wang, Li; Chang, Qing-rui; Wang, Xiao-xing; Shang, Yan

2015-07-01

Wuqi County of Shaanxi Province, where the vegetation recovering measures have been carried out for years, was taken as the study area. A total of 100 loess samples from 24 different profiles were collected. Total nitrogen (TN) and alkali hydrolysable nitrogen (AHN) contents of the soil samples were analyzed, and the soil samples were scanned in the visible/near-infrared (VNIR) region of 350-2500 nm in the laboratory. The calibration models were developed between TN and AHN contents and VNIR values based on correlation analysis (CA) and partial least squares regression (PLS). Independent samples validated the calibration models. The results indicated that the optimum model for predicting TN of loess was established by using first derivative of reflectance. The best model for predicting AHN of loess was established by using normal derivative spectra. The optimum TN model could effectively predict TN in loess from 0 to 40 cm, but the optimum AHN model could only roughly predict AHN at the same depth. This study provided a good method for rapidly predicting TN of loess where vegetation recovering measures have been adopted, but prediction of AHN needs to be further studied.

Apparent molar volumes and compressibilities of lanthanum, gadolinium and lutetium trifluoromethanesulfonates in dimethylsulfoxide

International Nuclear Information System (INIS)

Warmińska, Dorota; Wawer, Jarosław

2012-01-01

Highlights: ► Sequence of volumes and compressibilities of Ln 3+ ions in DMSO is: La 3+ > Gd 3+ 3+ . ► Sequence of the partial molar volumes do not change with temperature. ► These results are the consequence of nature of the ion–solvent bonding. - Abstract: Temperature dependencies of the densities of dimethylsulfoxide solutions of lanthanum, gadolinium and lutetium trifluoromethanesulfonates have been determined over a wide range of concentrations. The apparent molar volumes and partial molar volumes of the salts at infinite dilution, as well as the expansibilities of the salts, have been calculated from density data. Additionally, the apparent molar isentropic compressibilities of lanthanum, gadolinium and lutetium trifluoromethanesulfonates have been calculated from sound velocity data at 298.15 K. The data obtained have been interpreted in terms of ion−solvent interactions.

The optimum content of rubber ash in concrete: flexural strength

Science.gov (United States)

Senin, M. S.; Shahidan, S.; Shamsuddin, S. M.; Ariffin, S. F. A.; Othman, N. H.; Rahman, R.; Khalid, F. S.; Nazri, F. M.

2017-11-01

Discarded scrap tyres have become one of the major environmental problems nowadays. Several studies have been carried out to reuse waste tires as an additive or sand replacement in concrete with appropriate percentages of tire rubber, called as rubberized concrete to solve this problem. The main objectives of this study are to investigate the flexural strength performance of concrete when adding the rubber ash and also to analyse the optimum content of rubber ash in concrete prisms. The performance total of 30 number of concrete prisms in size of 100mm x 100mm x 500 mm were investigated, by partially replacement of rubber ash with percentage of 0%, 3%, 5%, 7% and 9% from the volume of the sand. The flexural strength is increased when percentage of rubber ash is added 3% from control concrete prism, RA 0 for both concrete prism age, 7 days and 28 days with value 1.21% and 0.976% respectively. However, for RA 5, RA 7 and RA 9, the flexural strength was decreased compared to the control for both age, 7 days and 28 days. In conclusion, 3% is the optimum content of rubber ash in concrete prism for both concrete age

Report on ISS Oxygen Production, Resupply, and Partial Pressure Management

Science.gov (United States)

Schaezler, Ryan; Ghariani, Ahmed; Leonard, Daniel; Lehman, Daniel

2011-01-01

The majority of oxygen used on International Space Station (ISS) is for metabolic support and denitrogenation procedures prior to Extra-Vehicular Activities. Oxygen is supplied by various visiting vehicles such as the Progress and Shuttle in addition to oxygen production capability on both the United States On-Orbit Segment (USOS) and Russian Segment (RS). To maintain a habitable atmosphere the oxygen partial pressure is controlled between upper and lower bounds. The full range of the allowable oxygen partial pressure along with the increased ISS cabin volume is utilized as a buffer allowing days to pass between oxygen production or direct addition of oxygen to the atmosphere from reserves. This paper summarizes amount of oxygen supplied and produced from all of the sources and describes past experience of managing oxygen partial pressure along with the range of management options available to the ISS.

Toxicity and cosmetic outcome of three-dimensional conformal radiotherapy for accelerated partial breast irradiation

International Nuclear Information System (INIS)

Gatti, M.; Bresciani, S.; Ponzone, R.; Panaia, R.; Salatino, A.; Stasi, M.; Gabriele, P.

2011-01-01

Full text of publication follows: Purpose.- To analyse the incidence and severity of acute and late normal tissue toxicity and cosmetic outcome using three - dimensional conformal radiotherapy to deliver accelerated partial breast irradiation. Patients and Methods.- 70 patients with stage I disease were treated with three-dimensional conformal radiotherapy for accelerated partial breast irradiation, in an approved protocol. The prescribed dose was 34 Gy in all patients delivered in 10 fractions over 5 consecutive days. On all CT scans gross tumor volume (GTV ) was defined around surgical clips. A 1.5 cm margin was added in order to account for clinical target volume (CTV) . A margin of 1 cm was added to CTI to define the planning target volume (PTV). The dose-volume constraints were followed in accordance with the specifications as dictated in the NSABP/RTOG protocol. After treatment, patients underwent a clinical and cosmetic evaluation every 3 months. Late toxicity was evaluated according to the RTOG grading schema. The cosmetic assessment was performed by the physicians using the controlateral untreated breast as the reference (Harvard scale). Results.- Median patient age was 66 years (range 51-80). Median follow-up was 15 months (range 6-46). Tumor size was 2 cm in 4(6%). The mean value of the ratio between the PTV and the whole ipsilateral breast volume was 38 % and the median percentage whole breast volume that received 95 % of prescribed dose was 34% (range 16%-55%). The rate of G1 and G2 acute skin toxicity was 28% and 2% respectively and the late toxicity was 17% (G1). G2 or greater toxicities were not observed. The most pronounced G1 late toxicity was subcutaneous fibrosis, developed in 3 patients. The cosmetic outcome was excellent in 83% and good in 17%. Conclusion.- Accelerated partial breast irradiation using three-dimensional conformal radiotherapy is technically feasible with very low acute and late toxicity. Long-term results are needed to assess

Water resources data, Idaho, 2002; Volume 1. Great Basin and Snake River basin above King Hill

Science.gov (United States)

Brennan, T.S.; Lehmann, A.K.; Campbell, A.M.; O'Dell, I.; Beattie, S.E.

2003-01-01

Water resources data for the 2002 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The two volumes of this report contain discharge records for 196 stream-gaging stations and 15 irrigation diversions; stage only records for 5 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 78 stream-gaging stations and partial record sites, 3 lakes sites, and 383 groundwater wells; and water levels for 425 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Factors influencing liver and spleen volume changes after donor hepatectomy for living donor liver transplantation

International Nuclear Information System (INIS)

Bae, Ji Hee; Ryeom, Hunku; Song, Jung Hup

2013-01-01

To define the changes in liver and spleen volumes in the early postoperative period after partial liver donation for living-donor liver transplantation (LDLT) and to determine factors that influence liver and spleen volume changes. 27 donors who underwent partial hepatectomy for LDLT were included in this study. The rates of liver and spleen volume change, measured with CT volumetry, were correlated with several factors. The analyzed factors included the indocyanine green (ICG) retention rate at 15 minutes after ICG administration, preoperative platelet count, preoperative liver and splenic volumes, resected liver volume, resected-to-whole liver volume ratio (LV R /LV W ), resected liver volume to the sum of whole liver and spleen volume ratio [LV R /(LV W + SV 0 )], and pre and post hepatectomy portal venous pressures. In all hepatectomy donors, the volumes of the remnant liver and spleen were increased (increased rates, 59.5 ± 50.5%, 47.9 ± 22.6%). The increment rate of the remnant liver volume revealed a positive correlation with LV R /LV W (r = 0.759, p R /LV W influences the increment rate of the remnant liver volume.

Effect of total cementitious content on shear strength of high-volume fly ash concrete beams

International Nuclear Information System (INIS)

Arezoumandi, Mahdi; Volz, Jeffery S.; Ortega, Carlos A.; Myers, John J.

2013-01-01

Highlights: ► Existing design standards conservatively predicted the capacity of the HVFAC beams. ► In general, the HVFAC beams exceeded the code predicted shear strengths. ► The cementitious content did not have effect on the shear behavior of the HVFAC beams. - Abstract: The production of portland cement – the key ingredient in concrete – generates a significant amount of carbon dioxide. However, due to its incredible versatility, availability, and relatively low cost, concrete is the most consumed manmade material on the planet. One method of reducing concrete’s contribution to greenhouse gas emissions is the use of fly ash to replace a significant amount of the cement. This paper compares two experimental studies that were conducted to investigate the shear strength of full-scale beams constructed with high-volume fly ash concrete (HVFAC) – concrete with at least 50% of the cement replaced with fly ash. The primary difference between the two studies involved the amount of cementitious material, with one mix having a relatively high total cementitious content (502 kg/m 3 ) and the other mix having a relatively low total cementitious content (337 kg/m 3 ). Both mixes utilized a 70% replacement of portland cement with a Class C fly ash. Each of these experimental programs consisted of eight beams (six without shear reinforcing and two with shear reinforcing in the form of stirrups) with three different longitudinal reinforcement ratios. The beams were tested under a simply supported four-point loading condition. The experimental shear strengths of the beams were compared with both the shear provisions of selected standards (US, Australia, Canada, Europe, and Japan) and a shear database of conventional concrete (CC) specimens. Furthermore, statistical data analyses (both parametric and nonparametric) were performed to evaluate whether or not there is any statistically significant difference between the shear strength of both mixes. Results of these

Abscisic acid and pyrabactin improve vitamin C contents in raspberries.

Science.gov (United States)

Miret, Javier A; Munné-Bosch, Sergi

2016-07-15

Abscisic acid (ABA) is a plant growth regulator with roles in senescence, fruit ripening and environmental stress responses. ABA and pyrabactin (a non-photosensitive ABA agonist) effects on red raspberry (Rubus idaeus L.) fruit development (including ripening) were studied, with a focus on vitamin and antioxidant composition. Application of ABA and/or pyrabactin just after fruit set did not affect the temporal pattern of fruit development and ripening; neither provitamin A (carotenoids) nor vitamin E contents were modified. In contrast, ABA and pyrabactin altered the vitamin C redox state at early stages of fruit development and more than doubled vitamin C contents at the end of fruit ripening. These were partially explained by changes in ascorbate oxidation and recycling. Therefore, ABA and pyrabactin applications may be used to increase vitamin C content of ripe fruits, increasing fruit quality and value. However, treatments containing pyrabactin-combined with ABA or alone-diminished protein content, thus partially limiting its potential applicability. Copyright © 2016 Elsevier Ltd. All rights reserved.

Water resources data, Ohio: Water year 1991. Volume 1, Ohio River Basin excluding project data

Energy Technology Data Exchange (ETDEWEB)

Shindel, H.L.; Klingler, J.H.; Mangus, J.P.; Trimble, L.E.

1992-03-01

Water-resources data for the 1991 water year for Ohio consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, in two volumes, contains records for water discharge at 131 gaging stations, 378 wells, and 74 partial-record sites; and water levels at 431 observation wells. Also included are data from miscellaneous sites. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System collected by the US Geological Survey and cooperating State and Federal agencies in Ohio.

The effect of pre-anaesthetic fasting time and type of food on gastric content volume and acidity in dogs.

Science.gov (United States)

Savvas, Ioannis; Rallis, Timoleon; Raptopoulos, Dimitris

2009-11-01

To investigate the effect of pre-anaesthetic fasting time and variety of food on gastric content (GC) volume and pH in dogs. Randomized, cross-over, prospective experimental study. Fifteen mongrel dogs (nine females and six males 1-4 years old, weighing 10-24.5 kg). Each dog received the same seven treatments in random order: dry food 3 hours before anaesthesia (BA) (treatment 3D), canned food (half daily rate) 3 hours BA (treatment 3C), 0% fat cow milk 3 hours BA (treatment 3M), dry food 10 hours BA (treatment 10D), canned food 10 hours BA (treatment 10C), low fat canned food 10 hours BA (treatment 10F) and low protein canned food 10 hours BA (treatment 10P). All animals were pre-medicated with propionyl promazine and anaesthesia was induced with thiopental sodium and maintained with halothane. GC was aspirated using an orogastric catheter and its volume and pH were measured. Treatment 10F had significantly lower GC pH than all the 3-hour treatments. Treatments 10D and 10P had significantly lower pH than treatments 3D and 3C. Treatment 3M had significantly lower pH than the other 3-hour treatments. Treatment 3D had significantly greater gastric volume than treatments 3M, 10C, 10F and 10P. Canned food at half the daily rate administered 3 hours before anaesthesia did not increase significantly the GC volume compared to the other types of food used. The GC pH was also high. This type of food fed 3 hours before induction of anaesthesia may be of benefit in reduction of the incidence of gastro-oesophageal reflux during anaesthesia in dogs.

Functional analytic methods in complex analysis and applications to partial differential equations

International Nuclear Information System (INIS)

Mshimba, A.S.A.; Tutschke, W.

1990-01-01

The volume contains 24 lectures given at the Workshop on Functional Analytic Methods in Complex Analysis and Applications to Partial Differential Equations held in Trieste, Italy, between 8-19 February 1988, at the ICTP. A separate abstract was prepared for each of these lectures. Refs and figs

Entropy and convexity for nonlinear partial differential equations.

Science.gov (United States)

Ball, John M; Chen, Gui-Qiang G

2013-12-28

Partial differential equations are ubiquitous in almost all applications of mathematics, where they provide a natural mathematical description of many phenomena involving change in physical, chemical, biological and social processes. The concept of entropy originated in thermodynamics and statistical physics during the nineteenth century to describe the heat exchanges that occur in the thermal processes in a thermodynamic system, while the original notion of convexity is for sets and functions in mathematics. Since then, entropy and convexity have become two of the most important concepts in mathematics. In particular, nonlinear methods via entropy and convexity have been playing an increasingly important role in the analysis of nonlinear partial differential equations in recent decades. This opening article of the Theme Issue is intended to provide an introduction to entropy, convexity and related nonlinear methods for the analysis of nonlinear partial differential equations. We also provide a brief discussion about the content and contributions of the papers that make up this Theme Issue.

Coke from partially briquetted preheated coal mixtures

Energy Technology Data Exchange (ETDEWEB)

Belitskii, A.N.; Sklyar, M.G.; Toryanik, Eh.I.; Bronshtein, A.P.

1988-07-01

Analyzes effects of partial coal charge briquetting on coking and on quality of coke for metallurgy. Effects of mixing hot coal briquets on temperature and moisture of coal were investigated on an experimental scale in a coking plant. Coal with a moisture content of 12% was used. Coking mixture consisted of 30% briquets and 70% crushed coal. Fifteen minutes after briquet mixing with coal, the mean coal charge temperature increased to 100-105 C and moisture content was lower than 2-5%. Results of laboratory investigations were verified by tests on a commercial scale. Experiments showed briquetting of weakly caking or non-caking coal charge components to be an efficient way of preventing coke quality decline. Adding 15-20% briquets consisting of weakly caking coal did not influence coke quality. Mixing hot coal briquets reduced moisture content in crushed coal, increased its temperature and reduced coking time.

Radioimmunoassay of glandular kallikrein in human plasma after partial purification by immunoaffinity column

International Nuclear Information System (INIS)

Nishimura, Kazutaka; Inoue, Yoshikazu; Kokubu, Tatsuo

1987-01-01

Glandular kallikrein in human plasma was partially purified by immunoaffinity column and was measured by a radioimmunoassay (RIA). Plasma was diluted with an equal volume of 10 mmol/l sodium phosphate buffer, pH 7.4, containing 0.9% NaCl (PBS) and was applied to an immunoaffinity column from which glandular kallikrein was eluted with 3 mol/l NaSCN (20 ml). The enzymic fraction was concentrated with an Amicon PM 10 filter and dialyzed against PBS. The final recovery of the enzyme was 51.6 ± 1.6%, determined by using [ 125 I]kallikrein. The usable range of the standard curve covered 2.5-100 ng/tube. The coefficient of variation within the series was 5.9%, and the coefficient of variation between the series was 7.6%. In healthy controls, the plasma content of glandular kallikrein was 1.36 ± 0.39 ng/ml. In patients with acute pancreatitis, the plasma concentration was 8.02 ± 6.15 ng/ml, significantly different from the control group. (Auth.)

Qualitative and quantitative ultrasound assessment of gastric content

Directory of Open Access Journals (Sweden)

Flora Margarida Barra Bisinotto

Full Text Available Summary Objective: Pulmonary aspiration of the gastric contents is one of the most feared complications in anesthesia. Its prevention depends on preoperative fasting as well as identification of risky patients. A reliable diagnostic tool to assess gastric volume is currently lacking. The aim of this study performed on volunteers was to evaluate the feasibility of ultrasonography to identify qualitative and quantitative gastric content. Method: A standardized gastric scanning protocol was applied on 67 healthy volunteers to assess the gastric antrum in four different situations: fasting, after ingesting clear fluid, milk and a solid meal. A qualitative and quantitative assessment of the gastric content in the antrum was performed by a blinded sonographer. The antrum was considered either as empty, or containing clear or thick fluid, or solids. Total gastric volume was predicted based on a cross-sectional area of the antrum. A p-value less than 0.05 was considered statistically significant. Results: For each type of gastric content, the sonographic characteristics of the antrum and its content were described and illustrated. Sonographic qualitative assessment allowed to distinguish between an empty stomach and one with different kinds of meal. The predicted gastric volume was significantly larger after the consumption of any food source compared to fasting. Conclusion: Bedside sonography can determine the nature of gastric content. It is also possible to estimate the difference between an empty gastric antrum and one that has some food in it. Such information may be useful to estimate the risk of aspiration, particularly in situations when prandial status is unknown or uncertain.

Qualitative and quantitative ultrasound assessment of gastric content.

Science.gov (United States)

Bisinotto, Flora Margarida Barra; Pansani, Patrícia Luísa; Silveira, Luciano Alves Matias da; Naves, Aline de Araújo; Peixoto, Ana Cristina Abdu; Lima, Hellen Moreira de; Martins, Laura Bisinotto

2017-02-01

Pulmonary aspiration of the gastric contents is one of the most feared complications in anesthesia. Its prevention depends on preoperative fasting as well as identification of risky patients. A reliable diagnostic tool to assess gastric volume is currently lacking. The aim of this study performed on volunteers was to evaluate the feasibility of ultrasonography to identify qualitative and quantitative gastric content. A standardized gastric scanning protocol was applied on 67 healthy volunteers to assess the gastric antrum in four different situations: fasting, after ingesting clear fluid, milk and a solid meal. A qualitative and quantitative assessment of the gastric content in the antrum was performed by a blinded sonographer. The antrum was considered either as empty, or containing clear or thick fluid, or solids. Total gastric volume was predicted based on a cross-sectional area of the antrum. A p-value less than 0.05 was considered statistically significant. For each type of gastric content, the sonographic characteristics of the antrum and its content were described and illustrated. Sonographic qualitative assessment allowed to distinguish between an empty stomach and one with different kinds of meal. The predicted gastric volume was significantly larger after the consumption of any food source compared to fasting. Bedside sonography can determine the nature of gastric content. It is also possible to estimate the difference between an empty gastric antrum and one that has some food in it. Such information may be useful to estimate the risk of aspiration, particularly in situations when prandial status is unknown or uncertain.

Metabolic impact of partial volume correction of [18F]FDG PET-CT oncological studies on the assessment of tumor response to treatment.

Science.gov (United States)

Stefano, A; Gallivanone, F; Messa, C; Gilardi, M C; Gastiglioni, I

2014-12-01

The aim of this work is to evaluate the metabolic impact of Partial Volume Correction (PVC) on the measurement of the Standard Uptake Value (SUV) from [18F]FDG PET-CT oncological studies for treatment monitoring purpose. Twenty-nine breast cancer patients with bone lesions (42 lesions in total) underwent [18F]FDG PET-CT studies after surgical resection of breast cancer primitives, and before (PET-II) chemotherapy and hormone treatment. PVC of bone lesion uptake was performed on the two [18F]FDG PET-CT studies, using a method based on Recovery Coefficients (RC) and on an automatic measurement of lesion metabolic volume. Body-weight average SUV was calculated for each lesion, with and without PVC. The accuracy, reproducibility, clinical feasibility and the metabolic impact on treatment response of the considered PVC method was evaluated. The PVC method was found clinically feasible in bone lesions, with an accuracy of 93% for lesion sphere-equivalent diameter >1 cm. Applying PVC, average SUV values increased, from 7% up to 154% considering both PET-I and PET-II studies, proving the need of the correction. As main finding, PVC modified the therapy response classification in 6 cases according to EORTC 1999 classification and in 5 cases according to PERCIST 1.0 classification. PVC has an important metabolic impact on the assessment of tumor response to treatment by [18F]FDG PET-CT oncological studies.

Effects of moisture barrier and initial moisture content on the storage ...

African Journals Online (AJOL)

The two factors examined were moisture barrier at three levels namely: thick lining, thin lining and non-lining. The other factor included initial moisture content of the produce, namely, turgid and partially wilted. Partial wilting of the produce was achieved by exposing freshly harvested materials at ambient temperature to dry ...

Solid waste leach characteristics and contaminant-sediment interactions Volume 2: Contaminant transport under unsaturated moisture contents

International Nuclear Information System (INIS)

Lindenmeier, C.W.; Serne, R.J.; Conca, J.L.

1995-09-01

The objectives of this report and subsequent volumes include describing progress on (1) development and optimization of experimental methods to quantify the release of contaminants from solid wastes and their subsequent interactions with unsaturated sediments and (2) the creation of empirical data that become input parameters to performance assessment (PA) analyses for future Hanford Site disposal units and baseline risk assessments for inactive and existing solid waste disposal units. For this report, efforts focused on developing methodologies to evaluate contaminant transport in Trench 8 (W-5 Burial Ground) sediments under unsaturated (vadose zone) conditions. To accomplish this task, a series of flow-through column tests were run using standard saturated column systems, Wierenga unsaturated column systems (both commercial and modified), and the Unsaturated Flow Apparatus (UFA). The reactants investigated were 85 Sr, 236 U, and 238 U as reactive tracers, and tritium as a non-reactive tracer. Results indicate that for moderately unsaturated conditions (volumetric water contents >50 % of saturation), the Wierenga system performed reasonably well such that long water residence times (50-147 h) were achieved, and reasonably good steady-state flow conditions were maintained. The major drawbacks in using this system for reactive tracer work included (1) the inability to achieve reproducible and constant moisture content below 50% of saturation, (2) the four to six month time required to complete a single test, and (3) the propensity for mechanical failure resulting from laboratory power outages during the prolonged testing period

A Technique to Speedup Access to Web Contents

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 7; Issue 7. Web Caching - A Technique to Speedup Access to Web Contents. Harsha Srinath Shiva Shankar Ramanna. General Article Volume 7 Issue 7 July 2002 pp 54-62 ... Keywords. World wide web; data caching; internet traffic; web page access.

Effect of Copolymer Latexes on Physicomechanical Properties of Mortar Containing High Volume Fly Ash as a Replacement Material of Cement

Directory of Open Access Journals (Sweden)

El-Sayed Negim

2014-01-01

Full Text Available This paper investigates the physicomechanical properties of mortar containing high volume of fly ash (FA as partial replacement of cement in presence of copolymer latexes. Portland cement (PC was partially replaced with 0, 10, 20, 30 50, and 60% FA. Copolymer latexes were used based on 2-hydroxyethyl acrylate (2-HEA and 2-hydroxymethylacrylate (2-HEMA. Testing included workability, setting time, absorption, chemically combined water content, compressive strength, and scanning electron microscopy (SEM. The addition of FA to mortar as replacement of PC affected the physicomechanical properties of mortar. As the content of FA in the concrete increased, the setting times (initial and final were elongated. The results obtained at 28 days of curing indicate that the maximum properties of mortar occur at around 30% FA. Beyond 30% FA the properties of mortar reduce and at 60% FA the properties of mortar are lower than those of the reference mortar without FA. However, the addition of polymer latexes into mortar containing FA improved most of the physicomechanical properties of mortar at all curing times. Compressive strength, combined water, and workability of mortar containing FA premixed with latexes are higher than those of mortar containing FA without latexes.

The implementation of Open Text Content Server and its role in ...

African Journals Online (AJOL)

The increasing volume of content created in various media, makes it more and more challenging to manage it throughout its lifecycle. The Enterprise Content Management (ECM) tools available, can address the full scope of content management needs. Nevertheless, the key to a successful management of content ...

Higher Adolescent Body Mass Index is Associated with Lower Regional Gray and White Matter Volumes and Lower Levels of Positive Emotionality

Directory of Open Access Journals (Sweden)

James T Kennedy

2016-09-01

Full Text Available Adolescent obesity is associated with an increased chance of developing serious health risks later in life. Identifying the neurobiological and personality factors related to increases in adiposity is important to understanding what drives maladaptive consummatory and exercise behaviors that result in obesity. Previous research has largely focused on adults with few findings published on interactions among adiposity, brain structure, and personality. In this study, Voxel Based Morphometry (VBM was used to identify associations between gray and white matter volumes and increasing adiposity, as measured by Body Mass Index percentile (BMI%, in 137 adolescents (age range: 9-20 years, Body Mass Index percentile range: 5.16-99.56. Variations in gray and white matter volume and BMI% were then linked to individual differences in personality measures from the Multidimensional Personality Questionnaire (MPQ. After controlling for age and other covariates, BMI% correlated negatively with gray matter volume in the bilateral caudate (right: partial r = -0.338, left: r -0.404, medial prefrontal cortex (partial r = -0.339, anterior cingulate (partial r = -0.312, bilateral frontal pole (right: partial r = -0.368, left: r= -0.316, and uncus (partial r = -0.475 as well as white matter volume bilaterally in the anterior limb of the internal capsule (right: partial r = -0.34, left: r = -0.386, extending to the left middle frontal subgyral white matter. Agentic Positive Emotionality (PEM-AG was correlated negatively with BMI% (partial r = -0.384. PEM-AG was correlated positively with gray matter volume in the right uncus (partial r = 0.329. These results suggest that higher levels of adiposity in adolescents are associated with lower trait levels in reward-related personality domains, as well as structural variations in brain regions associated with reward processing, control, and sensory integration.

Methods for improving mechanical properties of partially stabilized zirconia and the resulting product

International Nuclear Information System (INIS)

Aronov, V.A.

1987-01-01

A method for improving mechanical surface properties of a rigid body comprising partially stabilized zirconia as a constituent is described comprising the following steps: (i) providing a rigid body having an exposed surface and an interior volume; (ii) subjecting the exposed surface region of partially stabilized zirconia to external heating to heat the exposed surface region to 1100 0 C-1600 0 C without heating the interior volume above 500 0 C-800 0 C; and (iii) cooling the rigid body to a temperature of less than 500 0 C to cause a portion of the exposed surface region to transform from the tetragonal lattice modification to the monoclinic lattice modification, thereby creating a compressive stress field in the exposed surface region and improving the mechanical surface properties of the exposed surface region. In a ceramic body comprising a first exposed region of a partially stabilized zirconia, and a second region of a partially stabilized zirconia at an interior portion of the ceramic body, the improvement is described comprising the ceramic body having in the first, exposed region a greater percentage of the monoclinic lattice modification than in the second region; having in the first, exposed region 5 percent to 100 percent in the monoclinic lattice modification; and having a molded surface finish in the first, exposed region; the first, exposed region being subjected to a compressive field resulting from the greater percentage of the monoclinic lattice modification

Toxicity and cosmetic outcome of three-dimensional conformal radiotherapy for accelerated partial breast irradiation

Energy Technology Data Exchange (ETDEWEB)

Gatti, M.; Bresciani, S.; Ponzone, R.; Panaia, R.; Salatino, A.; Stasi, M.; Gabriele, P. [IRCC, Candiolo (Italy)

2011-10-15

Full text of publication follows: Purpose.- To analyse the incidence and severity of acute and late normal tissue toxicity and cosmetic outcome using three - dimensional conformal radiotherapy to deliver accelerated partial breast irradiation. Patients and Methods.- 70 patients with stage I disease were treated with three-dimensional conformal radiotherapy for accelerated partial breast irradiation, in an approved protocol. The prescribed dose was 34 Gy in all patients delivered in 10 fractions over 5 consecutive days. On all CT scans gross tumor volume (GTV ) was defined around surgical clips. A 1.5 cm margin was added in order to account for clinical target volume (CTV) . A margin of 1 cm was added to CTI to define the planning target volume (PTV). The dose-volume constraints were followed in accordance with the specifications as dictated in the NSABP/RTOG protocol. After treatment, patients underwent a clinical and cosmetic evaluation every 3 months. Late toxicity was evaluated according to the RTOG grading schema. The cosmetic assessment was performed by the physicians using the controlateral untreated breast as the reference (Harvard scale). Results.- Median patient age was 66 years (range 51-80). Median follow-up was 15 months (range 6-46). Tumor size was < 10 mm in 33 patients (53%) and > 2 cm in 4(6%). The mean value of the ratio between the PTV and the whole ipsilateral breast volume was 38 % and the median percentage whole breast volume that received 95 % of prescribed dose was 34% (range 16%-55%). The rate of G1 and G2 acute skin toxicity was 28% and 2% respectively and the late toxicity was 17% (G1). G2 or greater toxicities were not observed. The most pronounced G1 late toxicity was subcutaneous fibrosis, developed in 3 patients. The cosmetic outcome was excellent in 83% and good in 17%. Conclusion.- Accelerated partial breast irradiation using three-dimensional conformal radiotherapy is technically feasible with very low acute and late toxicity. Long

Water resources data, Idaho, 2002; Volume 2. Upper Columbia River basin and Snake River basin below King Hill

Science.gov (United States)

Brennan, T.S.; Lehmann, A.K.; Campbell, A.M.; O'Dell, I.; Beattie, S.E.

2003-01-01

Water resources data for the 2002 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The two volumes of this report contain discharge records for 196 stream-gaging stations and 15 irrigation diversions; stage only records for 5 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 78 stream-gaging stations and partial record sites, 3 lakes sites, and 383 groundwater wells; and water levels for 425 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Densities, molar volumes, and isobaric expansivities of (d-xylose+hydrochloric acid+water) systems

International Nuclear Information System (INIS)

Zhang Qiufen; Yan Zhenning; Wang Jianji; Zhang Hucheng

2006-01-01

Densities of (d-xylose+HCl+water) have been measured at temperature in the range (278.15 to 318.15) K as a function of concentration of both d-xylose and hydrochloric acid. The densities have been used to estimate the molar volumes and isobaric expansivity of the ternary solutions. The molar volumes of the ternary solutions vary linearly with mole fraction of d-xylose. The standard partial molar volumes V 2,φ - bar for d-xylose in aqueous solutions of molality (0.2, 0.4, 0.7, 1.1, 1.6, and 2.1) mol.kg -1 HCl have been determined. In the investigated temperature range, the relation: V 2,φ - bar =c 1 +c 2 {(T/K)-273.15} 1/2 , can be used to describe the temperature dependence of the standard partial molar volumes. These results have, in conjunction with the results obtained in water, been used to deduce the standard volumes of transfer, Δ t V - bar , of d-xylose from water to aqueous HCl solutions. An increase in the transfer volume of d-xylose with increasing HCl concentrations has been explained by the stronger interactions of H + with the hydrophilic groups of d-xylose

Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET: I. Theory, error analysis, and stereologic comparison

DEFF Research Database (Denmark)

Lida, H; Law, I; Pakkenberg, B

2000-01-01

Limited spatial resolution of positron emission tomography (PET) can cause significant underestimation in the observed regional radioactivity concentration (so-called partial volume effect or PVE) resulting in systematic errors in estimating quantitative physiologic parameters. The authors have...... formulated four mathematical models that describe the dynamic behavior of a freely diffusible tracer (H215O) in a region of interest (ROI) incorporating estimates of regional tissue flow that are independent of PVE. The current study was intended to evaluate the feasibility of these models and to establish...... a methodology to accurately quantify regional cerebral blood flow (CBF) corrected for PVE in cortical gray matter regions. Five monkeys were studied with PET after IV H2(15)O two times (n = 3) or three times (n = 2) in a row. Two ROIs were drawn on structural magnetic resonance imaging (MRI) scans and projected...

PENGARUH JUMLAH ANGGOTA, VOLUME USAHA DAN LIKUIDITAS KOPERASI TERHADAP PERMINTAAN JASA AUDIT

Directory of Open Access Journals (Sweden)

Nanik Sri Utaminingsih

2012-03-01

Full Text Available Kebutuhan akan laporan keuangan yang bisa dipercaya sangatlah penting untuk mengambil keputusan. Permasalahan dari penelitian ini adalah apakah jumlah anggota, volume bisnis dan likuiditas secara parsial dan simultan mempengaruhi permintaan jasa audit. Populasi dalam penelitian ini adalah 765 koperasi dan sampelnya berjumlah 89 koperasi. Data yang digunakan adalah laporan keuangan koperasi pada tahun fiscal 2008. Data analisis yang digunakan adalah analisis deskriptif, multikolnearitas and logistic regression. Kesimpulan dari penelitian ini adalah variabel jumlah anggota dan likuiditas mempengaruhi permintaan jasa audit secara parsial sedangkan volume bisnis tidak mempengaruhi permintaan jasa audit. Secara simultan 3 variabel mempengaruhi permintaan jasa audit. The need for reliable financial statements, and can be trusted is necessary in making a decision. The problem in this study is whether which the number of members, the business volume and liquidity partially and simultaneously affect the demand for audit services. The population in this study were 765 cooperatives and the research sample is 89 cooperatives. The dependent variables in this study are demand audit services. While the independent variables are the number of members, the business vo-lume and liquidity of cooperatives. The data used in the form of cooperative financial reports, fiscal year 2008  with using descriptive analysis, multicolonearitas and logistic regression. The conclusion of this research is variable number of members, and liquidity, the partial affect on demand for audit services, while business volume is partially not influence the audit services. Simultaneously, the three indepen-dent variables influenced the demand for audit services.

Multi-channel 1-to-2 transition amplitudes in a finite volume

Energy Technology Data Exchange (ETDEWEB)

Briceno, Raul [JLAB; Hansen, Maxwell [Helmholtz Institute Mainz; Walker-Loud, Andre P [W& M. JLAB

2015-04-01

We derive a model-independent expression for finite-volume matrix elements. Specifically, we present a relativistic, non-perturbative analysis of the matrix element of an external current between a one-scalar in-state and a two-scalar out-state. Our result, which is valid for energies below higher-particle inelastic thresholds, generalizes the Lellouch-Luscher formula in two ways: we allow the external current to inject arbitrary momentum into the system and we allow for the final state to be composed an arbitrary number of strongly coupled two-particle states with arbitrary partial waves (including partial-wave mixing induced by the volume). We also illustrate how our general result can be applied to some key examples, such as heavy meson decays and meson photo production. Finally, we point out complications that arise involving unstable resonance states, such as B to K*+l+l when staggered or mixed-action/partially-quenched calculations are performed.

The Chiral and Angular Momentum Content of the ρ-Meson

Science.gov (United States)

Glozman, L. Ya.; Lang, C. B.; Limmer, M.

2010-01-01

It is possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark Fock component of a meson in the infrared, where mass is generated. Using the variational method and a set of interpolators that span a complete chiral basis we extract in a lattice QCD Monte Carlo simulation with n f = 2 dynamical light quarks the orbital angular momentum and spin content of the ρ-meson. We obtain in the infrared a simple 3 S 1 component as a leading component of the ρ-meson with a small admixture of the 3 D 1 partial wave, in agreement with the SU(6) flavor-spin symmetry.

Measurement and correlation of excess molar volumes for mixtures of 1-propanol and aromatic hydrocarbons

International Nuclear Information System (INIS)

Gahlyan, Suman; Rani, Manju; Maken, Sanjeev Kumar; Lee, Inkyu; Moon, Il

2015-01-01

Excess molar volumes (V m E ) have been measured at 303.15 K for 1-propanol+benzene or toluene or o- or m- or p-xylene mixtures using V-shape dilatometer. The V m E values, for an equimolar composition, vary in the order: benzene>toluene-m-xylene>o-xylene>p-xylene. The V m E data have been used to calculate partial molar volumes, excess partial molar volumes, and apparent molar volumes of 1-propanol and aromatic hydrocarbons over the entire range of composition. The excess volume data have also been interpreted in terms of graph-theoretical approach and Prigogine-Flory-Patterson theory (PFP). While PFP theory fails to predict the V m E values for systems with s-shaped V m E versus x 1 graph, the V m E values calculated by graph theory compare reasonably well with the corresponding experimental values. This graph theory analysis has further yielded information about the state of aggregation of pure components as well as of the mixtures

Harmonic analysis, partial differential equations and applications in honor of Richard L. Wheeden

CERN Document Server

Franchi, Bruno; Lu, Guozhen; Perez, Carlos; Sawyer, Eric

2017-01-01

This is a collection of contributed papers by many eminent Harmonic Analysts and specialists of Partial Differential equations. The papers focus on weighted norm equalities for singular integrals, focusing wave equations, degenerate elliptic equations, Navier-Stokes flow in two dimensions and Poincare-Sobolev inequalities in the setting of metric spaces equipped with measures among others. Many topics considered in this volume stem from the interests of Richard L. Wheeden whose contributions to Potential Theory, singular integral theory and degenerate elliptic PDE theory this volume honors. Luis Caffarelli, Sagun Chanillo, Bruno Franchi, Cristian Guttierez, Xiaojun Huang, Carlos Kenig, Ermanno Lanconelli, Eric Sawyer and Alexander Volberg, are some of the many contributors to this volume. .

Effects of partial desulfation on antioxidant and inhibition of DLD cancer cell of Ulva fasciata polysaccharide.

Science.gov (United States)

Shao, Ping; Pei, Yaping; Fang, Zhongxian; Sun, Peilong

2014-04-01

Ulva fasciata belonging to the family Ulvaceae, commonly known as 'sea lettuce', is an abundantly growing green seaweed in coastal seashore of South China. Three different molecular weight sulfated polysaccharides (UFP1, UFP2 and UFP3) were extracted and separated from U. fasciata by hot water extraction and ultrafiltration. The three native UFP fractions had partial desulfurization by solvolytic desulfation respectively and the effect of sulfate content on the exhibition of the antioxidant and anti-tumor capacities had been evaluated and compared. The results showed that each native polysaccharide (UFP1, UFP2, UFP3) with high sulfate content exhibited better antioxidant activities compared with the partial desulfated polysaccharides (DS-UFP1, DS-UFP2, DS-UFP3). Specifically, UFP2 with relatively high sulfate content, molecular weight and uronic acid content had consistently excellent antioxidant performances. However, UFP2 demonstrated the minimal inhibitory effects on growth of DLD intestinal cancer cells. Instead, DS-UFP3 with the lowest sulfate content but highest uronic acid content and molecular weight exhibited the best antitumor activity. Copyright © 2014 Elsevier B.V. All rights reserved.

Partial differential equations methods, applications and theories

CERN Document Server

Hattori, Harumi

2013-01-01

This volume is an introductory level textbook for partial differential equations (PDE's) and suitable for a one-semester undergraduate level or two-semester graduate level course in PDE's or applied mathematics. Chapters One to Five are organized according to the equations and the basic PDE's are introduced in an easy to understand manner. They include the first-order equations and the three fundamental second-order equations, i.e. the heat, wave and Laplace equations. Through these equations we learn the types of problems, how we pose the problems, and the methods of solutions such as the separation of variables and the method of characteristics. The modeling aspects are explained as well. The methods introduced in earlier chapters are developed further in Chapters Six to Twelve. They include the Fourier series, the Fourier and the Laplace transforms, and the Green's functions. The equations in higher dimensions are also discussed in detail. This volume is application-oriented and rich in examples. Going thr...

Partial lower axillary dissection for patients with clinically node-negative breast cancer.

Science.gov (United States)

Kodama, H; Mise, K; Kan, N

2012-01-01

To evaluate retrospectively the outcomes of partial lower axillary lymph node dissection caudal to the intercostobrachial nerve in patients with clinically node-negative (N(0)) breast cancer. Numbers of dissected and metastatic nodes, overall and disease-free survival rates, postoperative complication rates, and axillary recurrence were compared between patients who underwent breast cancer surgery with partial axillary node dissection (n = 1043) and historical controls who underwent conventional dissection (n = 1084). The 5-year overall and disease-free survival rates were 95.6% and 89.7%, and 94.9% and 88.4%, respectively, in the partial dissection and conventional dissection groups; the differences were not significant. Mean duration of surgery (41.6 min versus 60.9 min), intraoperative blood loss (28.0 ml versus 51.3 ml), volume of lymphatic drainage at 2 weeks postoperatively (488 ml versus 836 ml), and persistent arm lymphoedema (0.0% versus 11.8%) were significantly different between the partial and conventional dissection groups, respectively. Partial axillary lymph node dissection was associated with similar survival rates (but lower postoperative complication rates) compared with conventional axillary dissection and is recommended in patients with N(0) breast cancer.

Technical Note: Deformable image registration on partially matched images for radiotherapy applications

International Nuclear Information System (INIS)

Yang Deshan; Goddu, S. Murty; Lu Wei; Pechenaya, Olga L.; Wu Yu; Deasy, Joseph O.; El Naqa, Issam; Low, Daniel A.

2010-01-01

In radiation therapy applications, deformable image registrations (DIRs) are often carried out between two images that only partially match. Image mismatching could present as superior-inferior coverage differences, field-of-view (FOV) cutoffs, or motion crossing the image boundaries. In this study, the authors propose a method to improve the existing DIR algorithms so that DIR can be carried out in such situations. The basic idea is to extend the image volumes and define the extension voxels (outside the FOV or outside the original image volume) as NaN (not-a-number) values that are transparent to all floating-point computations in the DIR algorithms. Registrations are then carried out with one additional rule that NaN voxels can match any voxels. In this way, the matched sections of the images are registered properly, and the mismatched sections of the images are registered to NaN voxels. This method makes it possible to perform DIR on partially matched images that otherwise are difficult to register. It may also improve DIR accuracy, especially near or in the mismatched image regions.

Plasma volume changes during hypoglycaemia: the effect of arterial blood sampling

DEFF Research Database (Denmark)

Hilsted, J; Bendtsen, F; Christensen, N J

1990-01-01

To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... hypoglycaemia. The magnitude of the changes in arterial and venous blood were not significantly different. These results indicate that the above changes in blood volume and composition are whole-body phenomena: furthermore, the major part of the changes are likely to occur in tissues other than upper extremity...

Four Decades of JDE Interviews: a Historical Content Analysis

Science.gov (United States)

Stahl, Norman A.; Theriault, Jennifer C.; Armstrong, Sonya L.

2016-01-01

This content analysis examines the topics, trends, and issues impacting developmental education and its professionals as evaluated by interviews that have appeared in the "Journal of Developmental Education" ("JDE") between the issuance of Volume 1 through Volume 39. A total of 76 interviews were analyzed with attention to…

Nonlinear partial differential equations and their applications

CERN Document Server

Lions, Jacques Louis

2002-01-01

This book contains the written versions of lectures delivered since 1997 in the well-known weekly seminar on Applied Mathematics at the Collège de France in Paris, directed by Jacques-Louis Lions. It is the 14th and last of the series, due to the recent and untimely death of Professor Lions. The texts in this volume deal mostly with various aspects of the theory of nonlinear partial differential equations. They present both theoretical and applied results in many fields of growing importance such as Calculus of variations and optimal control, optimization, system theory and control, op

Volumetric gain of the human pancreas after left partial pancreatic resection: A CT-scan based retrospective study.

Science.gov (United States)

Phillip, Veit; Zahel, Tina; Danninger, Assiye; Erkan, Mert; Dobritz, Martin; Steiner, Jörg M; Kleeff, Jörg; Schmid, Roland M; Algül, Hana

2015-01-01

Regeneration of the pancreas has been well characterized in animal models. However, there are conflicting data on the regenerative capacity of the human pancreas. The aim of the present study was to assess the regenerative capacity of the human pancreas. In a retrospective study, data from patients undergoing left partial pancreatic resection at a single center were eligible for inclusion (n = 185). Volumetry was performed based on 5 mm CT-scans acquired through a 256-slice CT-scanner using a semi-automated software. Data from 24 patients (15 males/9 females) were included. Mean ± SD age was 68 ± 11 years (range, 40-85 years). Median time between surgery and the 1st postoperative CT was 9 days (range, 0-27 days; IQR, 7-13), 55 days (range, 21-141 days; IQR, 34-105) until the 2nd CT, and 191 days (range, 62-1902; IQR, 156-347) until the 3rd CT. The pancreatic volumes differed significantly between the first and the second postoperative CT scans (median volume 25.6 mL and 30.6 mL, respectively; p = 0.008) and had significantly increased further by the 3rd CT scan (median volume 37.9 mL; p = 0.001 for comparison with 1st CT scan and p = 0.003 for comparison with 2nd CT scan). The human pancreas shows a measurable and considerable potential of volumetric gain after partial resection. Multidetector-CT based semi-automated volume analysis is a feasible method for follow-up of the volume of the remaining pancreatic parenchyma after partial pancreatectomy. Effects on exocrine and endocrine pancreatic function have to be evaluated in a prospective manner. Copyright © 2015 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Cast Partial Denture versus Acrylic Partial Denture for Replacement of Missing Teeth in Partially Edentulous Patients

Directory of Open Access Journals (Sweden)

Pramita Suwal

2017-03-01

Full Text Available Aim: To compare the effects of cast partial denture with conventional all acrylic denture in respect to retention, stability, masticatory efficiency, comfort and periodontal health of abutments. Methods: 50 adult partially edentulous patient seeking for replacement of missing teeth having Kennedy class I and II arches with or without modification areas were selected for the study. Group-A was treated with cast partial denture and Group-B with acrylic partial denture. Data collected during follow-up visit of 3 months, 6 months, and 1 year by evaluating retention, stability, masticatory efficiency, comfort, periodontal health of abutment. Results: Chi-square test was applied to find out differences between the groups at 95% confidence interval where p = 0.05. One year comparison shows that cast partial denture maintained retention and stability better than acrylic partial denture (p< 0.05. The masticatory efficiency was significantly compromising from 3rd month to 1 year in all acrylic partial denture groups (p< 0.05. The comfort of patient with cast partial denture was maintained better during the observation period (p< 0.05. Periodontal health of abutment was gradually deteriorated in all acrylic denture group (p

Application of ERAS-model and Prigogine-Flory-Patterson theory to excess molar volumes for ternary mixtures of (2-chlorobutane + butylacetate + isobutanol) at T = 298.15 K

International Nuclear Information System (INIS)

Khanlarzadeh, K.; Iloukhani, H.

2011-01-01

Highlights: → Density of ternary and three binary mixtures of (2-chlorobutane + butylacetate + isobutanol) determined. → Excess molar volume, partial molar volume and apparent molar volume were calculated. → Excess molar volume was correlated as a function of mole fraction by using the Redlich-Kister and Cibulka equation for all mixtures. → The experimental results have been used to test the applicability of the ERAS-model and PFP theory. - Abstract: Densities of the ternary mixture consisting of {2-chlorobutane (1) + butylacetate (2) + isobutanol (3)} and related binary mixtures were measured over the whole range of composition at T = 298.15 K and ambient pressure. Excess molar volumes V m E for the mixtures were derived and correlated as a function of mole fraction by using the Redlich-Kister and the Cibulka equations for binary and ternary mixtures, respectively. From the experimental data, partial molar volumes, V-bar m,i excess partial molar volumes, V-bar i E partial molar volumes at infinite dilution V-bar m,i 0 and apparent molar volumes V-bar φ,i were also calculated. For all binary mixtures over the entire range of mole fractions V m E data are positive. The experimental results of the constituted binary mixtures have been used to test the applicability of the extended real associated solution (ERAS-model) and Prigogine-Flory-Paterson (PFP) theory.

Studies on the partial specific volume of a poly(ethylene glycol) derivative in different solvent systems

NARCIS (Netherlands)

Tziatzios, C.; Precup, A.A.; Weidl, C.H.; Schubert, U.S.; Schuck, P.; Durchschlag, H.; Mächtle, W.; Broek, van den J.A.; Schubert, D.

2002-01-01

The specific volume of charged supramolecular compounds dissolved in organic solvents varies considerably with the solvent system applied; in addition, it is influenced by the presence of salt. In this study we determined the specific volume of an uncharged molecule from the same molar mass range in

Free-volume study of ethylene - vinyl alcohol copolymer evaluated through positronium lifetime measurement

International Nuclear Information System (INIS)

Ito, K.; Hong-ling Li; Ujihira, Y.; Nomura, K.; Saito, Y.; Yamamoto, T.; Nishihara, Y.

2003-01-01

The free-volume, of size ranging from 0.2 to 0.4 nm in radius, in an ethylene-vinyl alcohol copolymer was estimated using positronium lifetime measurement to elucidate the dependence of oxygen permeability on the free-volume size and fraction, on the ethylene content and on the crystallinity. The permeability and the free-volume fraction with varying the ethylene content were well related and the relation was interpreted based on the free-volume theory near below and above the glass transition temperature. On the other hand, the crystallinity significantly influenced the fraction of the amorphous region, where the free-volume hole exists, along with a slight change of the free-volume size. The variation of the permeability with the crystalline degree cannot be explained from the averaged free-volume fraction estimated by the whole volume of the polymer, but the permeability correlated with the free-volume size apparently. (author)

Variations in pore characteristics in high volatile bituminous coals: Implications for coal bed gas content

Science.gov (United States)

Mastalerz, Maria; Drobniak, A.; Strapoc, D.; Solano-Acosta, W.; Rupp, J.

2008-01-01

The Seelyville Coal Member of the Linton Formation (Pennsylvanian) in Indiana was studied to: 1) understand variations in pore characteristics within a coal seam at a single location and compare these variations with changes occurring between the same coal at different locations, 2) elaborate on the influence of mineral-matter and maceral composition on mesopore and micropore characteristics, and 3) discuss implications of these variations for coal bed gas content. The coal is high volatile bituminous rank with R0 ranging from 0.57% to 0.60%. BET specific surface areas (determined by nitrogen adsorption) of the coals samples studied range from 1.8 to 22.9??m2/g, BJH adsorption mesopore volumes from 0.0041 to 0.0339??cm3/g, and micropore volumes (determined by carbon dioxide adsorption) from 0.0315 to 0.0540??cm3/g. The coals that had the largest specific surface areas and largest mesopore volumes occur at the shallowest depths, whereas the smallest values for these two parameters occur in the deepest coals. Micropore volumes, in contrast, are not depth-dependent. In the coal samples examined for this study, mineral-matter content influenced both specific surface area as well as mesopore and micropore volumes. It is especially clear in the case of micropores, where an increase in mineral-matter content parallels the decrease of micropore volume of the coal. No obvious relationships were observed between the total vitrinite content and pore characteristics but, after splitting vitrinite into individual macerals, we see that collotelinite influences both meso- and micropore volume positively, whereas collodetrinite contributes to the reduction of mesopore and micropore volumes. There are large variations in gas content within a single coal at a single location. Because of this variability, the entire thickness of the coal must be desorbed in order to determine gas content reliably and to accurately calculate the level of gas saturation. ?? 2008 Elsevier B.V. All

Octanol-Water Partition Coefficient from 3D-RISM-KH Molecular Theory of Solvation with Partial Molar Volume Correction.

Science.gov (United States)

Huang, WenJuan; Blinov, Nikolay; Kovalenko, Andriy

2015-04-30

The octanol-water partition coefficient is an important physical-chemical characteristic widely used to describe hydrophobic/hydrophilic properties of chemical compounds. The partition coefficient is related to the transfer free energy of a compound from water to octanol. Here, we introduce a new protocol for prediction of the partition coefficient based on the statistical-mechanical, 3D-RISM-KH molecular theory of solvation. It was shown recently that with the compound-solvent correlation functions obtained from the 3D-RISM-KH molecular theory of solvation, the free energy functional supplemented with the correction linearly related to the partial molar volume obtained from the Kirkwood-Buff/3D-RISM theory, also called the "universal correction" (UC), provides accurate prediction of the hydration free energy of small compounds, compared to explicit solvent molecular dynamics [ Palmer , D. S. ; J. Phys.: Condens. Matter 2010 , 22 , 492101 ]. Here we report that with the UC reparametrized accordingly this theory also provides an excellent agreement with the experimental data for the solvation free energy in nonpolar solvent (1-octanol) and so accurately predicts the octanol-water partition coefficient. The performance of the Kovalenko-Hirata (KH) and Gaussian fluctuation (GF) functionals of the solvation free energy, with and without UC, is tested on a large library of small compounds with diverse functional groups. The best agreement with the experimental data for octanol-water partition coefficients is obtained with the KH-UC solvation free energy functional.

Normative values for volume and fat content of the hip abductor muscles and their dependence on side, age and gender in a healthy population.

Science.gov (United States)

Marcon, Magda; Berger, Nicole; Manoliu, Andrei; Fischer, Michael A; Nanz, Daniel; Andreisek, Gustav; Ulbrich, Erika J

2016-04-01

To determine normative values for volume and fat content of the gluteus medius (GMed) and minimus (GMin) muscle in healthy volunteers and to evaluate their dependence on age, gender and leg dominance. The IRB approval was obtained for this study. 80 healthy volunteers (females, 40; males, 40; age range 20-62 years), divided into four age groups, were included. Fat- and water-signal-separated MR images of the pelvis were acquired on a 3.0 T MR with a 3-point mDIXON sequence. Normalized volume and fat-signal fraction (FSF) of the GMed (ViGMed, FSFGMed) and GMin (ViGMin, FSFGMin) muscles were determined. The overall mean volumes (normalized) and FSF ± SD: ViGMed 105.13 ± 16.30 cm(3); ViGMin 30.24 ± 5.15 cm(3); FSFGMed 8.13 ± 1.70 % and FSFGMin 9.89 ± 2.72 %. Comparing different age subgroups within each gender no significant differences were found concerning the volumes and FSFs (except FSFGMin in male subgroup aged 20-29 versus 50-62 years, P = 0.014). Comparing FSFs differences between the two genders, only in 20-29 years subgroup, FSFGMed (P =0.003) and FSFGMin (P =0.002) were greater in female. Volume differences between the two legs were not significant (P > 0.077); FSFGMed and FSFGMin (P =0.005 for both) were significantly lower in the dominant leg in female but not in male group (P = 0.454 for FSFGMed and P = 0.643 for FSFMin). No age dependency was evident for volume normative data for GMed and GMin and normative data for FSF values showed no age- or gender dependency.

A Prospective Pathologic Study to Define the Clinical Target Volume for Partial Breast Radiation Therapy in Women With Early Breast Cancer

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Brandon T., E-mail: Brandon.Nguyen@act.gov.au [Department of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Canberra Hospital, Radiation Oncology Department, Garran, ACT (Australia); Deb, Siddhartha [Department of Anatomical Pathology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Victorian Cancer Biobank, Cancer Council of Victoria, Carlton, Victoria (Australia); Fox, Stephen [Department of Anatomical Pathology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Hill, Prudence [Department of Anatomical Pathology, St. Vincent' s Hospital Melbourne, Fitzroy, Victoria (Australia); Collins, Marnie [Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Chua, Boon H. [Department of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); University of Melbourne, Parkville, Victoria (Australia)

2012-12-01

Purpose: To determine an appropriate clinical target volume for partial breast radiation therapy (PBRT) based on the spatial distribution of residual invasive and in situ carcinoma after wide local excision (WLE) for early breast cancer or ductal carcinoma in situ (DCIS). Methods and Materials: We performed a prospective pathologic study of women potentially eligible for PBRT who had re-excision and/or completion mastectomy after WLE for early breast cancer or DCIS. A pathologic assessment protocol was used to determine the maximum radial extension (MRE) of residual carcinoma from the margin of the initial surgical cavity. Women were stratified by the closest initial radial margin width: negative (>1 mm), close (>0 mm and {<=}1 mm), or involved. Results: The study population was composed of 133 women with a median age of 59 years (range, 27-82 years) and the following stage groups: 0 (13.5%), I (40.6%), II (38.3%), and III (7.5%). The histologic subtypes of the primary tumor were invasive ductal carcinoma (74.4%), invasive lobular carcinoma (12.0%), and DCIS alone (13.5%). Residual carcinoma was present in the re-excision and completion mastectomy specimens in 55.4%, 14.3%, and 7.2% of women with an involved, close, and negative margin, respectively. In the 77 women with a noninvolved radial margin, the MRE of residual disease, if present, was {<=}10 mm in 97.4% (95% confidence interval 91.6-99.5) of cases. Larger MRE measurements were significantly associated with an involved margin (P<.001), tumor size >30 mm (P=.03), premenopausal status (P=.03), and negative progesterone receptor status (P=.05). Conclusions: A clinical target volume margin of 10 mm would encompass microscopic residual disease in >90% of women potentially eligible for PBRT after WLE with noninvolved resection margins.

A Prospective Pathologic Study to Define the Clinical Target Volume for Partial Breast Radiation Therapy in Women With Early Breast Cancer

International Nuclear Information System (INIS)

Nguyen, Brandon T.; Deb, Siddhartha; Fox, Stephen; Hill, Prudence; Collins, Marnie; Chua, Boon H.

2012-01-01

Purpose: To determine an appropriate clinical target volume for partial breast radiation therapy (PBRT) based on the spatial distribution of residual invasive and in situ carcinoma after wide local excision (WLE) for early breast cancer or ductal carcinoma in situ (DCIS). Methods and Materials: We performed a prospective pathologic study of women potentially eligible for PBRT who had re-excision and/or completion mastectomy after WLE for early breast cancer or DCIS. A pathologic assessment protocol was used to determine the maximum radial extension (MRE) of residual carcinoma from the margin of the initial surgical cavity. Women were stratified by the closest initial radial margin width: negative (>1 mm), close (>0 mm and ≤1 mm), or involved. Results: The study population was composed of 133 women with a median age of 59 years (range, 27-82 years) and the following stage groups: 0 (13.5%), I (40.6%), II (38.3%), and III (7.5%). The histologic subtypes of the primary tumor were invasive ductal carcinoma (74.4%), invasive lobular carcinoma (12.0%), and DCIS alone (13.5%). Residual carcinoma was present in the re-excision and completion mastectomy specimens in 55.4%, 14.3%, and 7.2% of women with an involved, close, and negative margin, respectively. In the 77 women with a noninvolved radial margin, the MRE of residual disease, if present, was ≤10 mm in 97.4% (95% confidence interval 91.6-99.5) of cases. Larger MRE measurements were significantly associated with an involved margin (P 30 mm (P=.03), premenopausal status (P=.03), and negative progesterone receptor status (P=.05). Conclusions: A clinical target volume margin of 10 mm would encompass microscopic residual disease in >90% of women potentially eligible for PBRT after WLE with noninvolved resection margins.

Phase equilibria and excess molar volumes of tetrahydrofuran (1) + deuterium oxide (2)

International Nuclear Information System (INIS)

Lejcek, P.; Matous, J.; Novak, J.P.; Pick, J.

1975-01-01

Vapour + liquid equilibrium at 313.15 and 333.15K, liquid + liquid equilibrium throughout the whole region of limited miscibility, and excess molar volumes at 298.15K have been studied for tetrahydrofuran + deuterium oxide. The mixtures show large positive deviations from Raoult's law and a closed loop of limited miscibility. The modified Redlich-Kister equation has been used for the correlation of the vapour + liquid equilibrium. The computation has been carried out according to a recently proposed procedure which makes it possible to obtain such constants of the correlation relation which are not inconsistent with physical reality, i.e. with the complete miscibility (partial delta 2 G/deltax 1 2 >0) under experimental conditions. Thermodynamic consistency was checked by the classical Redlich-Kister test and the one proposed by Ulrichson and Stevenson. Excess molar volumes are negative at all compositions with a point of inflexion in the water-rich region which indicates the extremes in partial molar volumes. (author)

MODEL PERUBAHAN VOLUME KERIPIK BUAH SELAMA PROSES PENGGORENGAN SECARA VAKUM [Model for Volume Changes in Fruit Chips during Vacuum Frying

Directory of Open Access Journals (Sweden)

Jamaluddin1*

2011-06-01

Full Text Available Expansion and puffing are specific characteristics of fried products critical for consumer preferences. To obtain expanded and puffed dried products that fit well with consumer acceptance criteria, it is necessary to pay attention to the process conditions which change the raw material characteristics during frying. The important changes include volume and density ratio of the products during frying. Hypothetically, these changes are due to water vaporization and the decrease dry matter in the products. The objective of this research is to develop a mathematical model of volume and density ratio changes for jack fruit during vacuum frying as a function of water and starch content reductions. Samples were vacuum fried at 70–100OC and pressure of 80-90 kPa for 15–60 min. The parameters observed were volume and density as well as water and starch contents of samples before and after vacuum frying. The results showed that the developed model can be used to predict changes in volume and density ratio of jack fruit during vacuum frying.

Symmetric geometric transfer matrix partial volume correction for PET imaging: principle, validation and robustness

Science.gov (United States)

Sattarivand, Mike; Kusano, Maggie; Poon, Ian; Caldwell, Curtis

2012-11-01

Limited spatial resolution of positron emission tomography (PET) often requires partial volume correction (PVC) to improve the accuracy of quantitative PET studies. Conventional region-based PVC methods use co-registered high resolution anatomical images (e.g. computed tomography (CT) or magnetic resonance images) to identify regions of interest. Spill-over between regions is accounted for by calculating regional spread functions (RSFs) in a geometric transfer matrix (GTM) framework. This paper describes a new analytically derived symmetric GTM (sGTM) method that relies on spill-over between RSFs rather than between regions. It is shown that the sGTM is mathematically equivalent to Labbe's method; however it is a region-based method rather than a voxel-based method and it avoids handling large matrices. The sGTM method was validated using two three-dimensional (3D) digital phantoms and one physical phantom. A 3D digital sphere phantom with sphere diameters ranging from 5 to 30 mm and a sphere-to-background uptake ratio of 3-to-1 was used. A 3D digital brain phantom was used with four different anatomical regions and a background region with different activities assigned to each region. A physical sphere phantom with the same geometry and uptake as the digital sphere phantom was manufactured and PET-CT images were acquired. Using these three phantoms, the performance of the sGTM method was assessed against that of the GTM method in terms of accuracy, precision, noise propagation and robustness. The robustness was assessed by applying mis-registration errors and errors in estimates of PET point spread function (PSF). In all three phantoms, the results showed that the sGTM method has accuracy similar to that of the GTM method and within 5%. However, the sGTM method showed better precision and noise propagation than the GTM method, especially for spheres smaller than 13 mm. Moreover, the sGTM method was more robust than the GTM method when mis-registration errors or

Symmetric geometric transfer matrix partial volume correction for PET imaging: principle, validation and robustness

International Nuclear Information System (INIS)

Sattarivand, Mike; Caldwell, Curtis; Kusano, Maggie; Poon, Ian

2012-01-01

Limited spatial resolution of positron emission tomography (PET) often requires partial volume correction (PVC) to improve the accuracy of quantitative PET studies. Conventional region-based PVC methods use co-registered high resolution anatomical images (e.g. computed tomography (CT) or magnetic resonance images) to identify regions of interest. Spill-over between regions is accounted for by calculating regional spread functions (RSFs) in a geometric transfer matrix (GTM) framework. This paper describes a new analytically derived symmetric GTM (sGTM) method that relies on spill-over between RSFs rather than between regions. It is shown that the sGTM is mathematically equivalent to Labbe's method; however it is a region-based method rather than a voxel-based method and it avoids handling large matrices. The sGTM method was validated using two three-dimensional (3D) digital phantoms and one physical phantom. A 3D digital sphere phantom with sphere diameters ranging from 5 to 30 mm and a sphere-to-background uptake ratio of 3-to-1 was used. A 3D digital brain phantom was used with four different anatomical regions and a background region with different activities assigned to each region. A physical sphere phantom with the same geometry and uptake as the digital sphere phantom was manufactured and PET-CT images were acquired. Using these three phantoms, the performance of the sGTM method was assessed against that of the GTM method in terms of accuracy, precision, noise propagation and robustness. The robustness was assessed by applying mis-registration errors and errors in estimates of PET point spread function (PSF). In all three phantoms, the results showed that the sGTM method has accuracy similar to that of the GTM method and within 5%. However, the sGTM method showed better precision and noise propagation than the GTM method, especially for spheres smaller than 13 mm. Moreover, the sGTM method was more robust than the GTM method when mis-registration errors or

Measurement and correlation of excess molar volumes for mixtures of 1-propanol and aromatic hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Gahlyan, Suman; Rani, Manju; Maken, Sanjeev Kumar [Deenbandhu Chhotu Ram University of Science and Technology, Murthal (India); Lee, Inkyu; Moon, Il [Yonsei University, Seoul (Korea, Republic of)

2015-01-15

Excess molar volumes (V{sub m}{sup E} ) have been measured at 303.15 K for 1-propanol+benzene or toluene or o- or m- or p-xylene mixtures using V-shape dilatometer. The V{sub m}{sup E} values, for an equimolar composition, vary in the order: benzene>toluene-m-xylene>o-xylene>p-xylene. The V{sub m}{sup E} data have been used to calculate partial molar volumes, excess partial molar volumes, and apparent molar volumes of 1-propanol and aromatic hydrocarbons over the entire range of composition. The excess volume data have also been interpreted in terms of graph-theoretical approach and Prigogine-Flory-Patterson theory (PFP). While PFP theory fails to predict the V{sub m}{sup E} values for systems with s-shaped V{sub m}{sup E} versus x{sub 1} graph, the V{sub m}{sup E} values calculated by graph theory compare reasonably well with the corresponding experimental values. This graph theory analysis has further yielded information about the state of aggregation of pure components as well as of the mixtures.

Increased putamen volume in adults with autism spectrum disorder

Directory of Open Access Journals (Sweden)

Wataru eSato

2014-11-01

Full Text Available Basal ganglia (BG abnormalities are implicated in the pathophysiology of autism spectrum disorder (ASD. However, studies measuring the volume of the entire BG in individuals with ASD have reported discrepant findings, and no study conducted volume measurement of the entire substructures of the BG (the caudate, putamen, nucleus accumbens, and globus pallidus in individuals with ASD. We delineated the BG substructures and measured their volumes in 29 adults with ASD without intellectual disabilities and 29 age- and gender-matched typically developed adult controls. We acquired T1-weighted anatomical images and performed semi-automated delineation and volume measurements of the above-mentioned subregions. Total cerebral volumes, sex, and ages were partialed out. Compared with controls, the putamen was significantly larger in the ASD group. The increased volume of the putamen found in high-functioning adults with ASD suggests that structural or histological abnormalities of the putamen may underlie the pathologies of ASD such as repetitive and stereotyped behaviors and impaired social interactions.

Content validity and its estimation

Directory of Open Access Journals (Sweden)

Yaghmale F

2003-04-01

Full Text Available Background: Measuring content validity of instruments are important. This type of validity can help to ensure construct validity and give confidence to the readers and researchers about instruments. content validity refers to the degree that the instrument covers the content that it is supposed to measure. For content validity two judgments are necessary: the measurable extent of each item for defining the traits and the set of items that represents all aspects of the traits. Purpose: To develop a content valid scale for assessing experience with computer usage. Methods: First a review of 2 volumes of International Journal of Nursing Studies, was conducted with onlyI article out of 13 which documented content validity did so by a 4-point content validity index (CV! and the judgment of 3 experts. Then a scale with 38 items was developed. The experts were asked to rate each item based on relevance, clarity, simplicity and ambiguity on the four-point scale. Content Validity Index (CVI for each item was determined. Result: Of 38 items, those with CVIover 0.75 remained and the rest were discarded reSulting to 25-item scale. Conclusion: Although documenting content validity of an instrument may seem expensive in terms of time and human resources, its importance warrants greater attention when a valid assessment instrument is to be developed. Keywords: Content Validity, Measuring Content Validity

Credibility Perceptions of User Generated Content

OpenAIRE

Murugan, S.; Nagarajan, Dr. P.S.

2017-01-01

Social media users generate a large volume of user generated content in various social media platforms to share their experiences in using a brand or a service. In the travel industry, the user generated content reviews are used by the prospective travellers to decide their travel plans. In the 1950’s credibility research of the media was started when television was introduced as a new media in the world dominated by newspapers. In the Social Media platforms, the credibility assessment is muc...

Wear and related evaluations of partially stabilized ZrO2

International Nuclear Information System (INIS)

Rice, R.W.; Wu, C.C.

1985-01-01

Pin-On-Disk (POD) tests show partially stabilized ZrO 2 (PSZ) crystals to have about the same wear as fully stabilized ZrO 2 crystals unit stabilizer contents are low enough (e.g., 4-5 wt % Y 2 O 3 ) so that some monoclinc ZrO 2 is present. Then wear increases substantially as stabilizer content is further reduced, and monoclinic content increases. Tests of PSZ-crystal cutting tools have not proved particularly successful, and rolling-contact fatigue tests of various PSZ materials showed them to be poor candidates for rolling-element bearings, with the later results indicating a petch-type dependence. Possible reasons for such limited or poor performance of PSZ, despite its good toughness, are discussed. Poor performance with concentrated loads is noted in particular, indicating limitations due to plastic flow

Apparent molar volumes and compressibilities of electrolytes and ions in γ-butyrolactone

International Nuclear Information System (INIS)

Krakowiak, Joanna; Wawer, Jarosław; Farmas, Aleksander

2012-01-01

Highlights: ► Density and speed of sound for salts solutions in γ-butyrolactone were measured. ► The apparent molar volumes and compressibilities have been determined. ► The limiting molar quantities are split into independent ionic contributions. ► These data are used to describe ion–solvent interactions. - Abstract: The densities of tetraphenylphosphonium bromide, sodium tetraphenylborate, lithium perchlorate, sodium perchlorate and lithium bromide in γ-butyrolactone at (288.15, 293.15, 298.15, 303.15, 308.15 and 313.15) K and speed of sound at 298.15 K have been measured. From these data apparent molar volumes V Φ at (288.15, 293.15, 298.15, 303.15, 308.15 and 313.15) K and the apparent molar isentropic compressibility K S,Φ , at T = 298.15 K of the salts have been determined. The apparent molar volumes and the apparent molar isentropic compressibilities were fitted to the Redlich, Rosenfeld and Mayer equation as well as to the Pitzer and Masson equations yielding infinite dilution data. The obtained limiting values have been used to estimate the ionic data of the standard partial molar volume and the standard partial isentropic compressibility in γ-butyrolactone solutions.

Effect of alloy content on microstructure and microchemistry of ...

Indian Academy of Sciences (India)

Administrator

malizing and tempering processes as well as during sub- sequent thermal exposure or service is sensitive to the alloying content in addition to .... K showing the retention of lath structure and (c) 1033 K showing a partial recovery of martensite.

Phenolic content, physical and sensory properties of breads made with different types of barley wort.

Science.gov (United States)

Baiano, Antonietta; Viggiani, Ilaria; Terracone, Carmela; Romaniello, Roberto; Del Nobile, Matteo Alessandro

2015-10-01

Barley wort, an intermediate product of beer brewing, is rich in phenolic compounds. The aim of this work was to evaluate the possibility of increasing the antioxidant content of bread by replacing water with three types of wort: two of them withdrawn at the end of the mashing operation during the production of a Pilsner and a Double Malt Pilsner beer respectively; the other collected at an intermediate stage of mashing of the Pilsner beer. The chemical, physical and sensory properties of the wort-added breads were compared with those of a control bread. All three worts led to increased phenolic content, volume and specific volume of the breads and induced significant changes in 11 of 23 sensory descriptors. The highest phenolic contents were detected in breads made either with the Pilsner wort withdrawn at an intermediate stage of mashing or with the Double Malt Pilsner wort. The former also gave the highest increase in volume and specific volume but significantly reduced the scores for crunchiness, firmness and cohesiveness. The latter led to lower increases in volume and specific volume, but less significant changes in the sensory properties were associated with its use. Worts can be conveniently used to increase the antioxidant content of bread. However, different types of wort can modify to different extents the physical and sensory properties of the product. © 2014 Society of Chemical Industry.

Ultrasound gel minimizes third body debris with partial hardware removal in joint arthroplasty

Directory of Open Access Journals (Sweden)

Aidan C. McGrory

2017-03-01

Full Text Available Hundreds of thousands of revision surgeries for hip, knee, and shoulder joint arthroplasties are now performed worldwide annually. Partial removal of hardware during some types of revision surgeries may create significant amounts of third body metal, polymer, or bone cement debris. Retained debris may lead to a variety of negative health effects including damage to the joint replacement. We describe a novel technique for the better containment and easier removal of third body debris during partial hardware removal. We demonstrate hardware removal on a hip joint model in the presence and absence of water-soluble gel to depict the reduction in metal debris volume and area of spread.

Regulated phosphorylation of the K-Cl cotransporter KCC3 at dual C-terminal threonines is a potent switch of intracellular potassium content and cell volume homeostasis

Directory of Open Access Journals (Sweden)

Norma C. Adragna

2015-07-01

Full Text Available The defense of cell volume against excessive shrinkage or swelling is a requirement for cell function and organismal survival. Cell swelling triggers a coordinated homeostatic response termed regulatory volume decrease (RVD, resulting in K+ and Cl– efflux via the activation of K+ channels, volume-regulated anion channels (VRACs, and the K+-Cl– cotransporters, including KCC3. Here, we show genetic alanine (Ala substitution at threonines (Thr 991 and 1048 in the KCC3a isoform carboxyl-terminus, preventing inhibitory phosphorylation at these sites, not only significantly up-regulates KCC3a activity up to 25-fold in normally inhibitory isotonic conditions, but is also accompanied by reversal of activity of the related bumetanide-sensitive Na+-K+-2Cl– cotransporter isoform 1 (NKCC1. This results in a rapid (90 % reduction in intracellular K+ content (Ki via both Cl-dependent (KCC3a + NKCC1 and Cl-independent (DCPIB [VRAC inhibitor]-sensitive pathways, which collectively renders cells less prone to acute swelling in hypotonic osmotic stress. Together, these data demonstrate the phosphorylation state of Thr991/Thr1048 in the KCC3a encodes a potent switch of transporter activity, Ki homeostasis, and cell volume regulation, and reveal novel observations into the functional interaction among ion transport molecules involved in RVD.

Long-term results of preventive embolization of renal angiomyolipomas: evaluation of predictive factors of volume decrease

Energy Technology Data Exchange (ETDEWEB)

Hocquelet, A.; Cornelis, F.; Le Bras, Y.; Meyer, M.; Tricaud, E.; Lasserre, A.S.; Grenier, N. [Centre Hospitalier Universitaire Pellegrin, Diagnostic and Therapeutic Urology and Vascular Imaging, Bordeaux (France); Ferriere, J.M.; Robert, G. [Centre Hospitalier Universitaire Pellegrin, Urology Service, Bordeaux (France)

2014-08-15

To evaluate the efficacy of selective arterial embolization (SAE) of angiomyolipomas based on the percentage volume reduction after embolization and to identify predictive factors of volume decrease. Patients receiving prophylactic SAE of renal angiomyolipomas were included retrospectively over 3 years. The volume change after SAE and haemorrhagic or surgical events were recorded. Initial tumour volume, percentage tumour fat content, mean tumour density, embolic agent used, number of angiomyolipomas and tuberous sclerosis disease were evaluated as predictive factors of volume decrease. A total of 19 patients with 39 angiomyolipomas were included with median follow-up of 28 months (interquartile range 21-37 months). All treatments were technically successful (92 % primary and 8 % secondary). No distal bleeding or any increase in size or surgical nephrectomy after SAE was recorded. Mean volume reduction was 72 % (±24 %). Volumes before SAE (R{sup 2} = 0.276; p = 0.001), percentage fat content (R{sup 2} = 0.612; p < 0.0001) and mean angiomyolipoma density (R{sup 2} = 0.536; p < 0.0001) were identified as predictive factors of volume decrease. In multivariate regression, only percentage fat content influenced volume decreases. SAE is an efficient treatment for angiomyolipoma devascularisation and volume reduction. A significant reduction of volume is modulated by the initial volume and tissue composition of the tumour. (orig.)

8th conference on Finite Volumes for Complex Applications

CERN Document Server

Omnes, Pascal

2017-01-01

This first volume of the proceedings of the 8th conference on "Finite Volumes for Complex Applications" (Lille, June 2017) covers various topics including convergence and stability analysis, as well as investigations of these methods from the point of view of compatibility with physical principles. It collects together the focused invited papers comparing advanced numerical methods for Stokes and Navier–Stokes equations on a benchmark, as well as reviewed contributions from internationally leading researchers in the field of analysis of finite volume and related methods, offering a comprehensive overview of the state of the art in the field. The finite volume method in its various forms is a space discretization technique for partial differential equations based on the fundamental physical principle of conservation, and recent decades have brought significant advances in the theoretical understanding of the method. Many finite volume methods preserve further qualitative or asymptotic properties, including m...

Liver regeneration and restoration of liver function after partial hepatectomy in patients with liver tumors

NARCIS (Netherlands)

Jansen, P. L.; Chamuleau, R. A.; van Leeuwen, D. J.; Schipper, H. G.; Busemann-Sokole, E.; van der Heyde, M. N.

1990-01-01

Liver regeneration and restoration of liver function were studied in six patients who underwent partial hepatectomy with removal of 30-70% of the liver. Liver volume and liver regeneration were studied by single-photon computed tomography (SPECT), using 99mTc-colloid as tracer. The method was

How rich is consciousness? The partial awareness hypothesis.

Science.gov (United States)

Kouider, Sid; de Gardelle, Vincent; Sackur, Jérôme; Dupoux, Emmanuel

2010-07-01

Current theories of consciousness posit a dissociation between 'phenomenal' consciousness (rich) and 'access' consciousness (limited). Here, we argue that the empirical evidence for phenomenal consciousness without access is equivocal, resulting either from a confusion between phenomenal and unconscious contents, or from an impression of phenomenally rich experiences arising from illusory contents. We propose a refined account of access that relies on a hierarchy of representational levels and on the notion of partial awareness, whereby lower and higher levels are accessed independently. Reframing of the issue of dissociable forms of consciousness into dissociable levels of access provides a more parsimonious account of the existing evidence. In addition, the rich phenomenology illusion can be studied and described in terms of testable cognitive mechanisms. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Summarizing Audiovisual Contents of a Video Program

Science.gov (United States)

Gong, Yihong

2003-12-01

In this paper, we focus on video programs that are intended to disseminate information and knowledge such as news, documentaries, seminars, etc, and present an audiovisual summarization system that summarizes the audio and visual contents of the given video separately, and then integrating the two summaries with a partial alignment. The audio summary is created by selecting spoken sentences that best present the main content of the audio speech while the visual summary is created by eliminating duplicates/redundancies and preserving visually rich contents in the image stream. The alignment operation aims to synchronize each spoken sentence in the audio summary with its corresponding speaker's face and to preserve the rich content in the visual summary. A Bipartite Graph-based audiovisual alignment algorithm is developed to efficiently find the best alignment solution that satisfies these alignment requirements. With the proposed system, we strive to produce a video summary that: (1) provides a natural visual and audio content overview, and (2) maximizes the coverage for both audio and visual contents of the original video without having to sacrifice either of them.

Impact of MLC leaf width on the quality of the dose distribution in partial breast irradiation

International Nuclear Information System (INIS)

Height, Felicity J.; Kron, Tomas; Willis, David; Chua, Boon H.

2012-01-01

Partial-breast irradiation (PBI) aims to limit the target volume for radiotherapy in women with early breast cancer after partial mastectomy to the region at highest risk of local recurrence, the tumor bed. Multileaf collimators are used to achieve conformal radiation beam portals required for PBI. Narrower leaf widths are generally assumed to allow more conformal shaping of beam portals around irregularly shaped target volumes. The aim was to compare 5-mm and 10-mm leaf widths for patients previously treated using PBI and assess subsequent planning target volume (PTV) coverage and organ at risk (OAR) doses for 16 patients. Several plans (5-mm leaf width or 10-mm leaf width) were generated for each patient using the original treated plan as the basis for attempts at further optimization. Alternating between different leaf widths found no significant difference in terms of overall PTV coverage and OAR doses between treatment plans. Optimization of the original treated plan allowed a small decrease in ipsilateral breast dose, which was offset by a lower PTV minimum. No significant dosimetric difference was found to support an advantage of 5-mm over 10-mm leaf width in this setting.

Recurrent Partial Words

Directory of Open Access Journals (Sweden)

Francine Blanchet-Sadri

2011-08-01

Full Text Available Partial words are sequences over a finite alphabet that may contain wildcard symbols, called holes, which match or are compatible with all letters; partial words without holes are said to be full words (or simply words. Given an infinite partial word w, the number of distinct full words over the alphabet that are compatible with factors of w of length n, called subwords of w, refers to a measure of complexity of infinite partial words so-called subword complexity. This measure is of particular interest because we can construct partial words with subword complexities not achievable by full words. In this paper, we consider the notion of recurrence over infinite partial words, that is, we study whether all of the finite subwords of a given infinite partial word appear infinitely often, and we establish connections between subword complexity and recurrence in this more general framework.

Size and Carbon Content of Sub-seafloor Microbial Cells at Landsort Deep, Baltic Sea

DEFF Research Database (Denmark)

Braun, Stefan; Morono, Yuki; Littmann, Sten

2016-01-01

determined the volume and the carbon content of microbial cells from a marine sediment drill core retrieved by the Integrated Ocean Drilling Program (IODP), Expedition 347, at Landsort Deep, Baltic Sea. To determine their shape and volume, cells were separated from the sediment matrix by multi-layer density......-specific carbon content was 19–31 fg C cell−1, which is at the lower end of previous estimates that were used for global estimates of microbial biomass. The cell-specific carbon density increased with sediment depth from about 200 to 1000 fg C μm−3, suggesting that cells decrease their water content and grow...... small cell sizes as adaptation to the long-term subsistence at very low energy availability in the deep biosphere. We present for the first time depth-related data on the cell volume and carbon content of sedimentary microbial cells buried down to 60 m below the seafloor. Our data enable estimates...

Constrained Optimization and Optimal Control for Partial Differential Equations

CERN Document Server

Leugering, Günter; Griewank, Andreas

2012-01-01

This special volume focuses on optimization and control of processes governed by partial differential equations. The contributors are mostly participants of the DFG-priority program 1253: Optimization with PDE-constraints which is active since 2006. The book is organized in sections which cover almost the entire spectrum of modern research in this emerging field. Indeed, even though the field of optimal control and optimization for PDE-constrained problems has undergone a dramatic increase of interest during the last four decades, a full theory for nonlinear problems is still lacking. The cont

Effects of partial volume correction on discrimination between very early Alzheimer's dementia and controls using brain perfusion SPECT

International Nuclear Information System (INIS)

Kanetaka, Hidekazu; Matsuda, Hiroshi; Ohnishi, Takashi; Imabayashi, Etsuko; Tanaka, Fumiko; Asada, Takashi; Yamashita, Fumio; Nakano, Seigo; Takasaki, Masaru

2004-01-01

We assessed the accuracy of brain perfusion single-photon emission computed tomography (SPECT) in discriminating between patients with probable Alzheimer's disease (AD) at the very early stage and age-matched controls before and after partial volume correction (PVC). Three-dimensional MRI was used for PVC. We randomly divided the subjects into two groups. The first group, comprising 30 patients and 30 healthy volunteers, was used to identify the brain area with the most significant decrease in regional cerebral blood flow (rCBF) in patients compared with normal controls based on the voxel-based analysis of a group comparison. The second group, comprising 31 patients and 31 healthy volunteers, was used to study the improvement in diagnostic accuracy provided by PVC. A Z score map for a SPECT image of a subject was obtained by comparison with mean and standard deviation SPECT images of the healthy volunteers for each voxel after anatomical standardization and voxel normalization to global mean or cerebellar values using the following equation: Z score = ([control mean]-[individual value])/(control SD). Analysis of receiver operating characteristics curves for a Z score discriminating AD and controls in the posterior cingulate gyrus, where a significant decrease in rCBF was identified in the first group, showed that the PVC significantly enhanced the accuracy of the SPECT diagnosis of very early AD from 73.9% to 83.7% with global mean normalization. The PVC mildly enhanced the accuracy from 73.1% to 76.3% with cerebellar normalization. This result suggests that early diagnosis of AD requires PVC in a SPECT study. (orig.)

The chiral and angular momentum content of the ρ-meson

International Nuclear Information System (INIS)

Glozman, L.Y.; Lang, C.B.; Limmer, M.

2010-01-01

It is possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark Fock component of a meson in the infrared, where mass is generated. Using the variational method and a set of interpolators that span a complete chiral basis we extract in a lattice QCD Monte Carlo ρ-meson with a small admixture of the 3 D 1 partial wave, in agreement with the SU (6) flavor-spin symmetry. (author)

Aperiodic Volume Optics

Science.gov (United States)

Gerke, Tim D.

Presented in this thesis is an investigation into aperiodic volume optical devices. The three main topics of research and discussion are the aperiodic volume optical devices that we call computer-generated volume holograms (CGVH), defects within periodic 3D photonic crystals, and non-periodic, but ordered 3D quasicrystals. The first of these devices, CGVHs, are designed and investigated numerically and experimentally. We study the performance of multi-layered amplitude computer-generated volume holograms in terms of efficiency and angular/frequency selectivity. Simulation results show that such aperiodic devices can increase diffraction efficiency relative to periodic amplitude volume holograms while maintaining angular and wavelength selectivity. CGVHs are also designed as voxelated volumes using a new projection optimization algorithm. They are investigated using a volumetric diffraction simulation and a standard 3D beam propagation technique as well as experimentally. Both simulation and experiment verify that the structures function according to their design. These represent the first diffractive structures that have the capacity for generating arbitrary transmission and reflection wave fronts and that provide the ability for multiplexing arbitrary functionality given different illumination conditions. Also investigated and discussed in this thesis are 3D photonic crystals and quasicrystals. We demonstrate that these devices can be fabricated using a femtosecond laser direct writing system that is particularly appropriate for fabrication of such arbitrary 3D structures. We also show that these devices can provide 3D partial bandgaps which could become complete bandgaps if fabricated using high index materials or by coating lower index materials with high index metals. Our fabrication method is particularly suited to the fabrication of engineered defects within the periodic or quasi-periodic systems. We demonstrate the potential for fabricating defects within

Assessment of bone mineral content in the internal bone volume

International Nuclear Information System (INIS)

Hoeiseth, A.; Alho, A.; Husby, T.; Ullevaal Sykehus, Oslo

1991-01-01

A method for assessing values related to bone density and mass is described. Mean attenuation and pixel area are measured in pixels selected on the basis of CT units. The method is to a large extent computerized and not dependent on manual positioning or outlining of a region of interest. Because it is not dependent on a comparatively large volume of homogeneous bone it can be used to make assessments even in very heterogeneous bones including cortical bone. The method is adaptable for measurement in all parts of the skeleton and values related to both bone density (DRV) and bone mass (MRV) are derived. The measurements in the femoral condyles were shown to have a precision of approximately 0.25 to 0.30 Z-score units (standard deviation of the measurements expressed in Z-score units). The agreement between chemically analyzed calcium density (weight of calcium per volume) and DRV was little less than 0.50 Z-scores and 0.30 Z-scores for the chemically determined calcium mass and the MRV. The agreement with mechanical bone strength was 0.78 Z-scores for DRV and 0.64 for the MRV. Altering scan parameters or measuring approaches gave systematic differences in the measurements. There were, however, good linear correlations between the measurements which show that these different measuring approaches essentially gave identical measurements. (orig.)

Estimation of free volumes of polystyrene by positron annihilation life-time technique

International Nuclear Information System (INIS)

Li, Hong-Ling; Ujihira, Yusuke; Nanasawa, Atsushi.

1996-01-01

Differences of size, content, and size distribution of free volumes in linear and three-armed polystyrenes, synthesized by radical, and anionic processes, were observed by positron annihilation lifetime measurements. For the polystyrene samples of different architectures and molecular weight distributions, the temperature dependence of an average free volume radius was quite similar to each other. The radius increased with increasing temperature (T), from 0.27 nm (60 K) to 0.30 nm (glass transition temperature: T g = 363 K), then to 0.35 nm (423 K), showing αβ transition temperature about 300 K. With increasing T, the free volume content decreased from 35% (60 K) to 25% (260 K) for radically polymerized linear polystyrene and to 22% (320 K) for anionically polymerized three-armed polystyrene, and then turned to increase to 35% at 350 K and 400 K, respectively. In contrast, the content for anionically polymerized linear polystyrene decreased from 45% (60 K) to 33% (300 K) and turned to increase to 35% at 350-400 K. The free volume content decreased reciprocally with an increase in the molecular weight at 333 K, suggesting differences in molecular motion between the edge and middle portions of the chain molecule. (author)

Healthy brain ageing assessed with 18F-FDG PET and age-dependent recovery factors after partial volume effect correction

Energy Technology Data Exchange (ETDEWEB)

Bonte, Stijn [IBiTech, Ghent, (Belgium); Ghent University, iMinds - Medical Image and Signal Processing (MEDISIP), Department of Electronics and Information Systems, Ghent (Belgium); University Hospital, Department of Radiology and Nuclear Medicine, Ghent (Belgium); Vandemaele, Pieter; Deblaere, Karel; Goethals, Ingeborg [University Hospital, Department of Radiology and Nuclear Medicine, Ghent (Belgium); Verleden, Stijn; Audenaert, Kurt [University Hospital, Department of Psychiatry, Ghent (Belgium); Holen, Roel van [Ghent University, iMinds - Medical Image and Signal Processing (MEDISIP), Department of Electronics and Information Systems, Ghent (Belgium)

2017-05-15

The mechanisms of ageing of the healthy brain are not entirely clarified to date. In recent years several authors have tried to elucidate this topic by using {sup 18}F-FDG positron emission tomography. However, when correcting for partial volume effects (PVE), divergent results were reported. Therefore, it is necessary to evaluate these methods in the presence of atrophy due to ageing. In this paper we first evaluate the performance of two PVE correction techniques with a phantom study: the Rousset method and iterative deconvolution. We show that the ability of the latter method to recover the true activity in a small region decreases with increasing age due to brain atrophy. Next, we have calculated age-dependent recovery factors to correct for this incomplete recovery. These factors were applied to PVE-corrected {sup 18}F-FDG PET scans of healthy subjects for mapping the agedependent metabolism in the brain. Many regions in the brain show a reduced metabolism with ageing, especially in grey matter in the frontal and temporal lobe. An increased metabolism is found in grey matter of the cerebellum and thalamus. Our study resulted in age-dependent recovery factors which can be applied following standard PVE correction methods. Cancelling the effect of atrophy, we found regional changes in {sup 18}F-FDG metabolism with ageing. A decreasing trend is found in the frontal and temporal lobe, whereas an increasing metabolism with ageing is observed in the thalamus and cerebellum.

Tooele Army Depot Revised Final Site-Wide Ecological Risk Assessment. Volume IV

National Research Council Canada - National Science Library

1998-01-01

Partial Contents: Soil samples, Biota Samples, Risk Assessment, Historic, Hazard, Herbicides, Metals, Pesticides, Dioxins, Furans, Invertebrate Data, Toxicity, Detection, Exposure, Bioaccumulation Models...

Volume loss as a tool to assess kiln drying of eucalyptus wood

OpenAIRE

Batista,Djeison Cesar; Klitzke,Ricardo Jorge; Rocha,Márcio Pereira da; Muñiz,Graciela Inez Bolzon de; Batista,Tharcia Ribeiro

2013-01-01

In this study, we aimed to analyze the kiln drying quality of Eucalyptus grandis, Eucalyptus saligna and Eucalyptus dunnii woods with respect to volume loss. Wood from the three species was kiln dried together with the same drying schedule and conditions in a conventional-temperature pilot kiln. Three kinds of volume loss were evaluated: total - from saturated (initial) to machined (final) condition; shrinkage - from saturated to 10% moisture content; and machining - from 10% moisture content...

Partial differential equations II elements of the modern theory equations with constant coefficients

CERN Document Server

Shubin, M

1994-01-01

This book, the first printing of which was published as Volume 31 of the Encyclopaedia of Mathematical Sciences, contains a survey of the modern theory of general linear partial differential equations and a detailed review of equations with constant coefficients. Readers will be interested in an introduction to microlocal analysis and its applications including singular integral operators, pseudodifferential operators, Fourier integral operators and wavefronts, a survey of the most important results about the mixed problem for hyperbolic equations, a review of asymptotic methods including short wave asymptotics, the Maslov canonical operator and spectral asymptotics, a detailed description of the applications of distribution theory to partial differential equations with constant coefficients including numerous interesting special topics.

Dosimetric investigation depending on tumor location in patient breast in partial breast irradiation

International Nuclear Information System (INIS)

Kim, Min Joo; Park, So Hyun; Jung, Joo Young; Woong, Cho; Suh, Tae Suk

2012-01-01

The Partial Breast Irradiation (PBI) technique, which involves radiation beam delivery techniques that use a limited range of treatment volumes, has been a challenging approach that is worthy of consideration compared to whole-breast radiation therapy (WBRT). Because of a small target volumes used in the PBI technique, the radiation dose can be safely delivered to the targeted tissue without the unwanted delivery of radiation to normal breast tissues and organ at risk (OAR), such as contralateral breast, lung and heart.Through PBI technique, better cosmetic outcomes and minimizing damages to OARs could be expected and also the daily dose can be increased with smaller number of fractionation in radiation therapy. The purpose of this study was to evaluate the dosimetric effects according to tumor locations in patient's breast for Partial Breast Irradiation (PBI) technique using three Dimensional Conformal Radiation Therapy (3DCRT), Electron Beam Radiation therapy (EBRT) and Helical-tomotherapy (H-TOMO). Dosimetric comparisons of PBI technique for 3DCRT, EBRT, and H-TOMO depending on the classified tumor locations were performed. H-TOMO delivered the low dose to lager volume to surrounding normal tissue, such as the heart and lungs compared to 3DCRT and EBRT although it had the same degree of target coverage as the other methods (3DCRT, EBRT). EBRT had a curative effect for early-stage breast cancers located in the lower and inner sections (LIQ-S, LIQ-D)

Blood Volume: Importance and Adaptations to Exercise Training, Environmental Stresses and Trauma Sickness

Science.gov (United States)

2000-02-01

because of limb atrophy, weight loss, and inactivity) because erythro- cyte levels of 2,3- diphosphoglycerate (2,3-DPG) were in- creased. However...blood volume expansion during exercise training may partially be explained by factors such as initial fitness level , training intensity, exercise mode...335 and their hydration level when measurements are made (131). Plasma volume expansion seems to be greatest when performing upright exercise on about

Dependence of mitochondrial and cytosolic adenine nucleotides on oxygen partial pressure in isolated hepatocytes. Application of a new rapid high pressure filtration technique for fractionation.

OpenAIRE

Hummerich, H; de Groot, H; Noll, T; Soboll, S

1988-01-01

By using a new rapid high pressure filtration technique, mitochondrial and cytosolic ATP and ADP contents were determined in isolated hepatocytes at different oxygen partial pressures. At 670 mmHg, subcellular adenine nucleotide contents and ATP/ADP ratios were comparable with values obtained with the digitonin fractionation technique. However at lower oxygen partial pressure ADP appears to be rephosphorylated during digitonin fractionation whereas with high pressure filtration fractionation ...

Simulation of consolidation in partially saturated soil materials

International Nuclear Information System (INIS)

Narasimhan, T.N.

1982-03-01

Partially saturated soil materials undergo consolidation, heave, collapse and failure due to changes in pore fluid pressure. The precise nature of the mechanics of such deformations is only poorly understood at present. Experimental evidence has shown that the volume change behavior of unsaturated soils cannot be adequately explained through changes in effective stress, even when a saturation dependent parameter is incorporated into the definition of effective stress. Two independent stress-state variables, involving combinations of total stress, pore air pressure and pore water pressure, are required to characterize volume changes and saturation changes in the partially saturated state. In general, two coupled conservation equations, one for the water-phase and the other for the air-phase need to be solved in order to predict the deformation behavior of unsaturated soils. If directional displacements and changes in the stress-field are required, then the conservation equations are to be integrated with an additional set of multi-dimensional force balance equations. For lack of a sufficient understanding of elastic constants such as Poisson's Ratio and Lame's constants as applied to unsaturated soils, little has been achieved so far in integrating the conservation equations and the force balance equations. For the long-term modeling of consolidation with respect to uranium mill tailings, it may be acceptable and economical to solve a single conservation equation for water, assuming that the air-phase is continuous and is at atmospheric pressure everywhere in the soil. The greatest challenge to modeling consolidation in the unsaturated zone at the presnt time is to develop enough experimental data defining the variation of void ratio and saturation with reference to the two chosen stress-state variables

Real options and volume uncertainty by field development projects

International Nuclear Information System (INIS)

Ekern, S.; Stensland, G.

1993-12-01

The report concerns a study on the use of option methodology in field development projects. The report shows how the value of flexibility in the different decision processes is to be found by means of real option methodology. Particular attention is laid on the uncertainty concerning the volume of reserves and production capacity. The results from the study were based on the research project dubbed ''Use of real options in field development projects''. The project is partially connected to another project dubbed ''Decisive behaviour and alternative action under uncertainty in the petroleum sector''. Main topics cover as follow: Example with volume uncertainty; real options and volume uncertainty; gradual disclosure of uncertainty in the production; value of flexible production equipment. 33 refs., 19 figs., 17 tabs

Astronomical Content in Rongorongo Tablet Keiti

DEFF Research Database (Denmark)

Wieczorek, Rafal

2011-01-01

Th e fi eld of rongorongo research: the study of Easter Island’s native script is in a peculiar state at the moment. While relative progress has been made in structural and statistical analysis in the last decades, at the level of both single glyphs as well as entire texts, little to no advanceme...... has been achieved in the actual decipherment. To shed new light on rongorongo research, a hypothesis regarding the contents of tablet Keiti, one of the 25 obtained artifacts, is proposed. Th e content, as well as the meaning, of all but one of these 25 rongorongo texts is still unknown....... In this publication, an interpretation for the recto side of tablet Keiti is presented. It is argued that the tablet contains astronomical observations or instructions regarding the Rapa Nui lunar calendar, and is similar in content to the only other rongorongo text whose function has been partially ascertained......: tablet Mamari. If the calendrical contents of this artifact were confi rmed, this would be a major boost to our understanding of Oceania’s only native script....

NATO Advanced Research Workshop on Approximation by Solutions of Partial Differential Equations, Quadrature Formulae, and Related Topics

CERN Document Server

Goldstein, M; Haussmann, W; Hayman, W; Rogge, L

1992-01-01

This volume consists of the proceedings of the NATO Advanced Research Workshop on Approximation by Solutions of Partial Differential Equations, Quadrature Formulae, and Related Topics, which was held at Hanstholm, Denmark. These proceedings include the main invited talks and contributed papers given during the workshop. The aim of these lectures was to present a selection of results of the latest research in the field. In addition to covering topics in approximation by solutions of partial differential equations and quadrature formulae, this volume is also concerned with related areas, such as Gaussian quadratures, the Pompelu problem, rational approximation to the Fresnel integral, boundary correspondence of univalent harmonic mappings, the application of the Hilbert transform in two dimensional aerodynamics, finely open sets in the limit set of a finitely generated Kleinian group, scattering theory, harmonic and maximal measures for rational functions and the solution of the classical Dirichlet problem. In ...

Bone mineral content (BMC) and serum vitamin D concentrations of infants fed partially hydrolyzed infant formulas

Science.gov (United States)

The purpose of the study was to compare the bone status of healthy, term infants fed partially hydrolyzed whey formulas during the first 3 mo of life. Between 0 and 8 d of age, 89 infants were randomized to Good Start Supreme (GSS) or an experimental whey-based formula (EF) to 84 d of age. BMC was a...

AdS Branes from Partial Breaking of Superconformal Symmetries

International Nuclear Information System (INIS)

Ivanov, E.A.

2005-01-01

It is shown how the static-gauge world-volume superfield actions of diverse superbranes on the AdS d+1 superbackgrounds can be systematically derived from nonlinear realizations of the appropriate AdS supersymmetries. The latter are treated as superconformal symmetries of flat Minkowski superspaces of the bosonic dimension d. Examples include the N = 1 AdS 4 supermembrane, which is associated with the 1/2 partial breaking of the OSp(1|4) supersymmetry down to the N = 1, d = 3 Poincare supersymmetry, and the T-duality related L3-brane on AdS 5 and scalar 3-brane on AdS 5 x S 1 , which are associated with two different patterns of 1/2 breaking of the SU(2, 2|1) supersymmetry. Another (closely related) topic is the AdS/CFT equivalence transformation. It maps the world-volume actions of the codimension-one AdS d+1 (super)branes onto the actions of the appropriate Minkowski (super)conformal field theories in the dimension d

SU-F-BRA-14: Optimization of Dosimetric Guidelines for Accelerated Partial Breast Irradiation (APBI) Using the Strut-Adjusted Volume Implant (SAVI)

International Nuclear Information System (INIS)

Mooney, K; Altman, M; Garcia-Ramirez, J; Thomas, M; Zoberi, I; Mullen, D; DeWees, T; Esthappan, J

2015-01-01

Purpose: Treatment planning guidelines for accelerated partial breast irradiation (ABPI) using the strut-adjusted volume implant (SAVI) are inconsistent between the manufacturer and NSABP B-39/RTOG 0413 protocol. Furthermore neither set of guidelines accounts for different applicator sizes. The purpose of this work is to establish guidelines specific to the SAVI that are based on clinically achievable dose distributions. Methods: Sixty-two consecutive patients were implanted with a SAVI and prescribed to receive 34 Gy in 10 fractions twice daily using high dose-rate (HDR) Ir-192 brachytherapy. The target (PTV-EVAL) was defined per NSABP. The treatments were planned and evaluated using a combination of dosimetric planning goals provided by the NSABP, the manufacturer, and our prior clinical experience. Parameters evaluated included maximum doses to skin and ribs, and volumes of PTV-EVAL receiving 90%, 95%, 100%, 150%, and 200% of the prescription (V90, etc). All target parameters were evaluated for correlation with device size using the Pearson correlation coefficient. Revised dosimetric guidelines for target coverage and heterogeneity were determined from this population. Results: Revised guidelines for minimum target coverage (ideal in parentheses): V90≥95%(97%), V95≥90%(95%), V100≥88%(91%). The only dosimetric parameters that were significantly correlated (p<0.05) with device size were V150 and V200. Heterogeneity criteria were revised for the 6–1 Mini/6-1 applicators to V150≤30cc and V200≤15cc, and unchanged for the other sizes. Re-evaluation of patient plans showed 90% (56/62) met the revised minimum guidelines and 76% (47/62) met the ideal guidelines. All and 56/62 patients met our institutional guidelines for maximum skin and rib dose, respectively. Conclusions: We have optimized dosimetric guidelines for the SAVI applicators, and found that implementation of these revised guidelines for SAVI treatment planning yielded target coverage exceeding

WE-EF-BRA-11: Precision Partial-Tumor Irradiation of Dorsal Rodent Mammary Tumors

Energy Technology Data Exchange (ETDEWEB)

Malcolm, J [Duke Medical Physics Graduate Program, Durham, NC (United States); Boss, K [Department of Comparative Biomedical Sciences, North Carolina State University (United States); Dewhirst, M [Dpt of Radiation and Cancer Biology, Duke University, Durham, North Carolina (United States); Oldham, M [Dpt of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

2015-06-15

Purpose: To introduce a pre-clinical treatment technique on a micro-irradiator to treat specific volumes of dorsal mammary tumors in BALB/c mice while sparing lungs and spine. This technique facilitates pre-clinical investigation of tumor response to sub-optimal radiation treatments in which a portion of the tumor is unirradiated, known as a “marginal miss”. In-vitro data suggests that partial tumor radiations trigger a more aggressive phenotype in non-irradiated, regional tumor cells via bystander effects. As the lung tissue is spared, the impact of marginal miss on the development of pulmonary metastasis may be assessed. Methods: End to end test was performed on three BALB/c mice as proof of concept for larger studies. 1Gy was delivered on the micro-irradiator employing previously unexplored lateral parallel-opposed diamond and/or triangle-shaped beams. The margins of the treatment beam were defined using a combination of tumor palpation, barium fiducial markers, and real-time fluoroscopic images. The dose distribution was independently verified with kilovoltage beam Monte Carlo dose calculations with 7% statistical uncertainty and double exposure images. As a final step, the technique was used in a larger pre-clinical study (15Gy, 36 BALB/c mice) and lung metastasis in response to tumor irradiation of 100%, 50% and 0% was quantified. Results: For the Monte-Carlo dose calculations, the dose volume histograms established a maximum dose within the un-irradiated and radiated portions of the mammary tumor of 0.3Gy and 1.5Gy respectively, with a sharp gradient at the boundary. 100% of the lung volume received less than 0.5Gy. This technique proved suitable for a pre-clinical marginal miss study with 50% more lung metastases in partially-radiated mouse models compared to completely. Conclusion: We have developed a novel treatment technique for partial or full irradiation of dorsal mammary tumors incorporating lung sparing.The technique will be useful for exploring

Angular Momentum Content of the ρ Meson in Lattice QCD

International Nuclear Information System (INIS)

Glozman, Leonid Ya.; Lang, C. B.; Limmer, Markus

2009-01-01

The variational method allows one to study the mixing of interpolators with different chiral transformation properties in the nonperturbatively determined physical state. It is then possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark component of a meson in the infrared, where mass is generated. Using a unitary transformation from the chiral basis to the 2S+1 L J basis one may extract a partial wave content of a meson. We present results for the ground state of the ρ meson using quenched simulations as well as simulations with n f =2 dynamical quarks, all for lattice spacings close to 0.15 fm. We point out that these results indicate a simple 3 S 1 -wave composition of the ρ meson in the infrared, like in the SU(6) flavor-spin quark model.

Angular Momentum Content of the ρ Meson in Lattice QCD

Science.gov (United States)

Glozman, Leonid Ya.; Lang, C. B.; Limmer, Markus

2009-09-01

The variational method allows one to study the mixing of interpolators with different chiral transformation properties in the nonperturbatively determined physical state. It is then possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark component of a meson in the infrared, where mass is generated. Using a unitary transformation from the chiral basis to the LJ2S+1 basis one may extract a partial wave content of a meson. We present results for the ground state of the ρ meson using quenched simulations as well as simulations with nf=2 dynamical quarks, all for lattice spacings close to 0.15 fm. We point out that these results indicate a simple S13-wave composition of the ρ meson in the infrared, like in the SU(6) flavor-spin quark model.

Comparison of Statistically Modeled Contaminated Soil Volume Estimates and Actual Excavation Volumes at the Maywood FUSRAP Site - 13555

Energy Technology Data Exchange (ETDEWEB)

Moore, James [U.S. Army Corps of Engineers - New York District 26 Federal Plaza, New York, New York 10278 (United States); Hays, David [U.S. Army Corps of Engineers - Kansas City District 601 E. 12th Street, Kansas City, Missouri 64106 (United States); Quinn, John; Johnson, Robert; Durham, Lisa [Argonne National Laboratory, Environmental Science Division 9700 S. Cass Ave., Argonne, Illinois 60439 (United States)

2013-07-01

As part of the ongoing remediation process at the Maywood Formerly Utilized Sites Remedial Action Program (FUSRAP) properties, Argonne National Laboratory (Argonne) assisted the U.S. Army Corps of Engineers (USACE) New York District by providing contaminated soil volume estimates for the main site area, much of which is fully or partially remediated. As part of the volume estimation process, an initial conceptual site model (ICSM) was prepared for the entire site that captured existing information (with the exception of soil sampling results) pertinent to the possible location of surface and subsurface contamination above cleanup requirements. This ICSM was based on historical anecdotal information, aerial photographs, and the logs from several hundred soil cores that identified the depth of fill material and the depth to bedrock under the site. Specialized geostatistical software developed by Argonne was used to update the ICSM with historical sampling results and down-hole gamma survey information for hundreds of soil core locations. The updating process yielded both a best guess estimate of contamination volumes and a conservative upper bound on the volume estimate that reflected the estimate's uncertainty. Comparison of model results to actual removed soil volumes was conducted on a parcel-by-parcel basis. Where sampling data density was adequate, the actual volume matched the model's average or best guess results. Where contamination was un-characterized and unknown to the model, the actual volume exceeded the model's conservative estimate. Factors affecting volume estimation were identified to assist in planning further excavations. (authors)

Dosimetric comparison of proton and photon three-dimensional, conformal, external beam accelerated partial breast irradiation techniques

International Nuclear Information System (INIS)

Kozak, Kevin R.; Katz, Angela; Adams, Judith C.; Crowley, Elizabeth M.; Nyamwanda, Jacqueline A.C.; Feng, Jennifer K.C.; Doppke, Karen P.; DeLaney, Thomas F.; Taghian, Alphonse G.

2006-01-01

Purpose: To compare the dosimetry of proton and photon-electron three-dimensional, conformal, external beam accelerated partial breast irradiation (3D-CPBI). Methods and Materials: Twenty-four patients with fully excised, Stage I breast cancer treated with adjuvant proton 3D-CPBI had treatment plans generated using the mixed-modality, photon-electron 3D-CPBI technique. To facilitate dosimetric comparisons, planning target volumes (PTVs; lumpectomy site plus 1.5-2.0 cm margin) and prescribed dose (32 Gy) were held constant. Plans were optimized for PTV coverage and normal tissue sparing. Results: Proton and mixed-modality plans both provided acceptable PTV coverage with 95% of the PTV receiving 90% of the prescribed dose in all cases. Both techniques also provided excellent dose homogeneity with a dose maximum exceeding 110% of the prescribed dose in only one case. Proton 3D-CPBI reduced the volume of nontarget breast tissue receiving 50% of the prescribed dose by an average of 36%. Statistically significant reductions in the volume of total ipsilateral breast receiving 100%, 75%, 50%, and 25% of the prescribed dose were also observed. The use of protons resulted in small, but statistically significant, reductions in the radiation dose delivered to 5%, 10%, and 20% of ipsilateral and contralateral lung and heart. The nontarget breast tissue dosimetric advantages of proton 3D-CPBI were not dependent on tumor location, breast size, PTV size, or the ratio of PTV to breast volume. Conclusions: Compared to photon-electron 3D-CPBI, proton 3D-CPBI significantly reduces the volume of irradiated nontarget breast tissue. Both approaches to accelerated partial breast irradiation offer exceptional lung and heart sparing

Partial tooth gear bearings

Science.gov (United States)

Vranish, John M. (Inventor)

2010-01-01

A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

Effect of bread gluten content on gastrointestinal function: a crossover MRI study on healthy humans.

Science.gov (United States)

Coletta, Marina; Gates, Fred K; Marciani, Luca; Shiwani, Henna; Major, Giles; Hoad, Caroline L; Chaddock, Gemma; Gowland, Penny A; Spiller, Robin C

2016-01-14

Gluten is a crucial functional component of bread, but the effect of increasing gluten content on gastrointestinal (GI) function remains uncertain. Our aim was to investigate the effect of increasing gluten content on GI function and symptoms in healthy participants using the unique capabilities of MRI. A total of twelve healthy participants completed this randomised, mechanistic, open-label, three-way crossover study. On days 1 and 2 they consumed either gluten-free bread (GFB), or normal gluten content bread (NGCB) or added gluten content bread (AGCB). The same bread was consumed on day 3, and MRI scans were performed every 60 min from fasting baseline up to 360 min after eating. The appearance of the gastric chime in the images was assessed using a visual heterogeneity score. Gastric volumes, the small bowel water content (SBWC), colonic volumes and colonic gas content and GI symptoms were measured. Fasting transverse colonic volume after the 2-d preload was significantly higher after GFB compared with NGCB and AGCB with a dose-dependent response (289 (SEM 96) v. 212 (SEM 74) v. 179 (SEM 87) ml, respectively; P=0·02). The intragastric chyme heterogeneity score was higher for the bread with increased gluten (AGCB 6 (interquartile range (IQR) 0·5) compared with GFB 3 (IQR 0·5); P=0·003). However, gastric half-emptying time was not different between breads nor were study day GI symptoms, postprandial SBWC, colonic volume and gas content. This MRI study showed novel mechanistic insights in the GI responses to different breads, which are poorly understood notwithstanding the importance of this staple food.

Cyclic PaO2 oscillations assessed in the renal microcirculation: correlation with tidal volume in a porcine model of lung lavage.

Science.gov (United States)

Thomas, Rainer; Möllmann, Christian; Ziebart, Alexander; Liu, Tanghua; David, Matthias; Hartmann, Erik K

2017-07-11

Oscillations of the arterial partial pressure of oxygen induced by varying shunt fractions occur during cyclic alveolar recruitment within the injured lung. Recently, these were proposed as a pathomechanism that may be relevant for remote organ injury following acute respiratory distress syndrome. This study examines the transmission of oxygen oscillations to the renal tissue and their tidal volume dependency. Lung injury was induced by repetitive bronchoalveolar lavage in eight anaesthetized pigs. Cyclic alveolar recruitment was provoked by high tidal volume ventilation. Oscillations of the arterial partial pressure of oxygen were measured in real-time in the macrocirculation by multi-frequency phase fluorimetry and in the renal microcirculation by combined white-light spectrometry and laser-Doppler flowmetry during tidal volume down-titration. Significant respiratory-dependent oxygen oscillations were detected in the macrocirculation and transmitted to the renal microcirculation in a substantial extent. The amplitudes of these oscillations significantly correlate to the applied tidal volume and are minimized during down-titration. In a porcine model oscillations of the arterial partial pressure of oxygen are induced by cyclic alveolar recruitment and transmitted to the renal microcirculation in a tidal volume-dependent fashion. They might play a role in organ crosstalk and remote organ damage following lung injury.

Table of content translations of Soviet reports received by the INDC Secretariat

International Nuclear Information System (INIS)

1982-07-01

The INDC Secretariat receives a number of Soviet reports in Russian as part of the INDC document distribution system. Because of their large number and size most of them cannot be translated by the IAEA. The ''Nuclear Physics Research in the USSR - Collected Abstracts'' report series and occasional reports of interest to the nuclear data community are translated by the IAEA on a regular basis, and are normally given a ''U'' distribution. The ''Table of Content Translations'' contain the translation of the table of contents (and abstracts when available) of those Soviet reports which the IAEA does not translate in full. The originals of these reports are normally available in limited quantities only and are given an INDC ''G'' distribution. This issue contains the table of content translation of the following reports: Nuclear Constants, volume 3(42), original distributed as INDC(CCP)-173/G; Nuclear Constants, volume 4(43), original distributed as INDC(CCP)-175/G; Nuclear Constants, volume 5(44); original distributed as INDC(CCP)-176/G

Water resources data, Ohio: Water year 1991. Volume 2, St. Lawrence River Basin: Statewide project data

Energy Technology Data Exchange (ETDEWEB)

Shindel, H.L.; Klingler, J.H.; Mangus, J.P.; Trimble, L.E.

1992-03-01

The Water Resources Division of the US Geological Survey (USGS), in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Ohio each water year. These data, accumulated during many years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the USGS, the data are published annually in this report series entitled ``Water Resources Data--Ohio.`` This report (in two volumes) includes records on surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 131 streamflow-gaging stations, 95 miscellaneous sites; (2) stage and content records for 5 streams, lakes, and reservoirs; (3) water-quality for 40 streamflow-gaging stations, 378 wells, and 74 partial-record sites; and (4) water levels for 431 observation wells.

Effective constants for wave propagation through partially saturated porous media

International Nuclear Information System (INIS)

Berryman, J.G.; Thigpen, L.

1985-01-01

The multipole scattering coefficients for elastic wave scattering from a spherical inhomogeneity in a fluid-saturated porous medium have been calculated. These coefficients may be used to obtain estimates of the effective macroscopic constants for long-wavelength propagation of elastic waves through partially saturated media. If the volume average of the single scattering from spherical bubbles of gas and liquid is required to vanish, the resulting equations determine the effective bulk modulus, density, and viscosity of the multiphase fluid filling the pores. The formula for the effective viscosity during compressional wave excitation is apparently new

Bound states on the lattice with partially twisted boundary conditions

International Nuclear Information System (INIS)

Agadjanov, D.; Guo, F.-K.; Ríos, G.; Rusetsky, A.

2015-01-01

We propose a method to study the nature of exotic hadrons by determining the wave function renormalization constant Z from lattice simulations. It is shown that, instead of studying the volume-dependence of the spectrum, one may investigate the dependence of the spectrum on the twisting angle, imposing twisted boundary conditions on the fermion fields on the lattice. In certain cases, e.g., the case of the DK bound state which is addressed in detail, it is demonstrated that the partial twisting is equivalent to the full twisting up to exponentially small corrections.

Partial dehydration and cryopreservation of Citrus seeds.

Science.gov (United States)

Graiver, Natalia; Califano, Alicia; Zaritzky, Noemí

2011-11-01

Three categories of seed storage behavior are generally recognized among plant species: orthodox, intermediate and recalcitrant. Intermediate seeds cannot be stored in liquid nitrogen (LN) without a previous partial dehydration process. The water content (WC) of the seeds at the moment of immersion in LN must be regarded as the most critical factor in cryopreservation. The purpose of this study was to investigate the basis of the optimal hydration status for cryopreservation of Citrus seeds: C. sinensis (sweet orange), C. paradisi (grapefruit), C. reticulata (mandarin) in LN. To study the tolerance to dehydration and LN exposure, seeds were desiccated by equilibration at relative humidities between 11 and 95%. Sorption isotherms were determined and modeled; lipid content of the seeds was measured. Seed desiccation sensitivity was quantified by the quantal response model. Differential scanning calorimetry (DSC) thermograms were determined on cotyledon tissue at different moisture contents to measure ice melting enthalpies and unfrozen WC. Samples of total seed lipid extract were also analyzed by DSC to identify lipid transitions in the thermograms. The limit of hydration for LN Citrus seeds treatment corresponded to the unfrozen WC in the tissue, confirming that seed survival strictly depended on avoidance of intracellular ice formation. Copyright © 2011 Society of Chemical Industry.

Hydrogeology of the 200 Areas low-level burial grounds: An interim report: Volume 2, Appendixes

Energy Technology Data Exchange (ETDEWEB)

Last, G.V.; Bjornstad, B.N.; Bergeron, M.P.; Wallace, D.W.; Newcomer, D.R.; Schramke, J.A.; Chamness, M.A.; Cline, C.S.; Airhart, S.P.; Wilbur, J.S.

1989-01-01

This report presents information derived form the installation of 35 ground-water monitoring wells around six low-level radioactive/hazardous waste burial grounds located in the 200 Areas of the Hanford Site in southeastern Washington State. This information was collected between May 20, 1987 and August 1, 1988. The contents of this report have been divided into two volumes. Volume 1 contains the main text. This Volume contains the appendixes, including data and supporting information that verify content and results found in the main text.

Finite volume at two-loops in chiral perturbation theory

International Nuclear Information System (INIS)

Bijnens, Johan; Rössler, Thomas

2015-01-01

We calculate the finite volume corrections to meson masses and decay constants in two and three flavour Chiral Perturbation Theory to two-loop order. The analytical results are compared with the existing result for the pion mass in two-flavour ChPT and the partial results for the other quantities. We present numerical results for all quantities.

The electric strength of high-voltage transformers insulation at effect of partial dischargers

International Nuclear Information System (INIS)

Khoshravan, E.; Zeraatparvar, A.; Gashimov, A.M.; Mehdizadeh, R.N.

2001-01-01

Full text : In paper the change of electric strength of high-voltage transformers insulation at the effect of partial discharges with space charge accumulation was investigated. It is revealed that the effect of partial discharges of insulation materials results the reduction of their pulsing electric strength which can restore the own initial value at releasing of saved charge the volume of a material under condition of absence the ineversible structural changes in it. Researches of high-voltage transformers insulation's non-failure operation conditions show, that at increasing of insulation work time in a strong electrical field the reduction of average breakdown voltages with simultaneous increasing of spread in discharge voltage values takes place. It authentically testifies to reduction of short-time discharge voltage of insulation materials during their electrical aging. As the basic reason of insulation electrical aging the partial discharges occurring in gas cavities inside insulation were considered. It is known that the space charges will be formed in insulation elements of high-voltage devices which effects in dielectrical property of these elements including the electric strength and the space charge formation can occur also at partial discharges in an alternating voltage while the service of high-voltage transformers. In the given work the experiments in revealing separate influence partial discharges in pulsing electric strength of insulation materials at presence and at absence inside them the space charge were spent

Influence of Barley Sourdough and Vacuum Cooling on Shelf Life Quality of Partially Baked Bread

Science.gov (United States)

2017-01-01

Summary Driven by the bakery industry urge to satisfy consumer demand for fresh, diverse and high quality bakery products, we investigated the influence of barley sourdough and vacuum cooling on shelf life quality of partially baked bread stored in modified atmosphere packaging at ambient conditions. Barley sourdough was fermented with Lactobacillus reuteri (DSM 20016, F275). Partially baked bread with sourdough was microbiologically acceptable during 30 days of storage, while bread without sourdough had detectable mould on the 30th day. Stored bread samples were rebaked after 1, 8, 15, 22 and 30 days to determine moisture content, physical and sensorial properties. Moisture loss (5%) was detected on the 15th day, after which it remained stable until the end of investigated storage period. Nevertheless, textural quality of stored bread continuously declined due to crumb firming. Bread flavour did not change during mould-free storage time. The principal component analysis identified major differences in the flavour of sour and control bread, also in crumb firmness and moisture content of samples. This study indicates the positive role of barley sourdough fermented with L. reuteri in improving crumb texture for at least 15 days, and ensuring mould- and bacteria-free partially baked bread for 30 days. Vacuum cooling combined with sourdough improved bread shape, porosity, and reduced sour taste, crust colouring and crumbliness. Hence, it can successfully extend shelf life quality of partially baked bread in modified atmosphere packaging. PMID:29540981

English language teaching textbooks content, consumption, production

CERN Document Server

Harwood, N

2013-01-01

English language teaching textbooks (or coursebooks) play a central role in the life of a classroom. This edited volume contains research-informed chapters focusing on: analysis of textbook content; how textbooks are used in the classroom; and textbook writers' accounts of the materials writing, design, and publishing process.

Recent trends in operator theory and partial differential equations the Roland Duduchava anniversary volume

CERN Document Server

Natroshvili, David; Shargorodsky, Eugene; Wendland, Wolfgang

2017-01-01

This volume is dedicated to the eminent Georgian mathematician Roland Duduchava on the occasion of his 70th birthday. It presents recent results on Toeplitz, Wiener-Hopf, and pseudodifferential operators, boundary value problems, operator theory, approximation theory, and reflects the broad spectrum of Roland Duduchava's research. The book is addressed to a wide audience of pure and applied mathematicians.

Theoretical study for volume changes associated with the helix-coil transition of peptides.

Science.gov (United States)

Imai, T; Harano, Y; Kovalenko, A; Hirata, F

2001-12-01

We calculate the partial molar volumes and their changes associated with the coil(extended)-to-helix transition of two types of peptide, glycine-oligomer and glutamic acid-oligomer, in aqueous solutions by using the Kirkwood-Buff solution theory coupled with the three-dimensional reference interaction site model (3D-RISM) theory. The volume changes associated with the transition are small and positive. The volume is analyzed by decomposing it into five contributions following the procedure proposed by Chalikian and Breslauer: the ideal volume, the van der Waals volume, the void volume, the thermal volume, and the interaction volume. The ideal volumes and the van der Waals volumes do not change appreciably upon the transition. In the both cases of glycine-peptide and glutamic acid-peptide, the changes in the void volumes are positive, while those in the thermal volumes are negative, and tend to balance those in the void volumes. The change in the interaction volume of glycine-peptide does not significantly contribute, while that of glutamic acid-peptide makes a negative contribution. Copyright 2001 John Wiley & Sons, Inc. Biopolymers 59: 512-519, 2001

Activated carbon oxygen content influence on water and surfactant adsorption.

Science.gov (United States)

Pendleton, Phillip; Wu, Sophie Hua; Badalyan, Alexander

2002-02-15

This research investigates the adsorption properties of three activated carbons (AC) derived from coconut, coal, and wood origin. Each carbon demonstrates different levels of resistance to 2 M NaOH treatment. The coconut AC offers the greatest and wood AC the least resistance. The influence of base treatment is mapped in terms of its effects on specific surface area, micropore volume, water adsorption, and dodecanoic acid adsorption from both water and 2 M NaOH solution. A linear relationship exists between the number of water molecules adsorbed at the B-point of the water adsorption isotherm and the oxygen content determined from elemental analysis. Surfactant adsorption isotherms from water and 2 M NaOH indicate that the AC oxygen content effects a greater dependence on affinity for surfactant than specific surface area and micropore volume. We show a linear relationship between the plateau amount of surfactant adsorbed and the AC oxygen content in both water and NaOH phases. The higher the AC oxygen content, the lower the amount of surfactant adsorbed. In contrast, no obvious relationship could be drawn between the surfactant amount adsorbed and the surface area.

Influence of moisture condition on chloride diffusion in partially saturated ordinary Portland cement mortar

NARCIS (Netherlands)

Zhang, Y.; Zhang, M.; Ye, G.

2018-01-01

Experiments have been carried out to study the influence of moisture condition, including moisture content and its distribution, on the chloride diffusion in partially saturated ordinary Portland cement mortar. The mortar samples with water-to-cement (w/c) ratios of 0.4, 0.5 and 0.6, cured for 1

Ascorbic Acid Contents in Chili Peppers (Capsicum L.

Directory of Open Access Journals (Sweden)

Owk ANIEL KUMAR

2009-12-01

Full Text Available The genus Capsicum commonly known as chili pepper is a major spice crop and is almost cosmopolitan in distribution. The nutritive value of chili pepper is largely determined by ascorbic acid content. The fruits at five ripening stages viz., (M1, M2, M3, M4 and M5 from seventeen cultivars of Capsicum annuum L and one cultivar of Capsicum frutescens L were analyzed for ascorbic acid content. Among eighteen genotypes the C. annuum var. IC: 119262(CA2 showed higher ascorbic acid content (mg/100g FW i.e., 208.00.68 (M1, 231.00.66 (M2, 280.00.31 (M3, 253.00.34 (M4 and 173.70.27 (M5. The study revealed that the gradual increase in ascorbic acid content from green to red and subsequently declined in the lateral stages (red partially dried and red fully dried fruits. The variability of ascorbic acid content in the genotypes suggests that these selected genotypes may be use full as parents in hybridization programs to produce fruits with good nutritional values.

Clinical Experience With Image-Guided Radiotherapy in an Accelerated Partial Breast Intensity-Modulated Radiotherapy Protocol

International Nuclear Information System (INIS)

Leonard, Charles E.; Tallhamer, Michael M.S.; Johnson, Tim; Hunter, Kari C.M.D.; Howell, Kathryn; Kercher, Jane; Widener, Jodi; Kaske, Terese; Paul, Devchand; Sedlacek, Scot; Carter, Dennis L.

2010-01-01

Purpose: To explore the feasibility of fiducial markers for the use of image-guided radiotherapy (IGRT) in an accelerated partial breast intensity modulated radiotherapy protocol. Methods and Materials: Nineteen patients consented to an institutional review board approved protocol of accelerated partial breast intensity-modulated radiotherapy with fiducial marker placement and treatment with IGRT. Patients (1 patient with bilateral breast cancer; 20 total breasts) underwent ultrasound guided implantation of three 1.2- x 3-mm gold markers placed around the surgical cavity. For each patient, table shifts (inferior/superior, right/left lateral, and anterior/posterior) and minimum, maximum, mean error with standard deviation were recorded for each of the 10 BID treatments. The dose contribution of daily orthogonal films was also examined. Results: All IGRT patients underwent successful marker placement. In all, 200 IGRT treatment sessions were performed. The average vector displacement was 4 mm (range, 2-7 mm). The average superior/inferior shift was 2 mm (range, 0-5 mm), the average lateral shift was 2 mm (range, 1-4 mm), and the average anterior/posterior shift was 3 mm (range, 1 5 mm). Conclusions: This study shows that the use of IGRT can be successfully used in an accelerated partial breast intensity-modulated radiotherapy protocol. The authors believe that this technique has increased daily treatment accuracy and permitted reduction in the margin added to the clinical target volume to form the planning target volume.

Robust model of fresh jujube soluble solids content with near ...

African Journals Online (AJOL)

A robust partial least square (PLS) calibration model with high accuracy and stability was established for the measurement of soluble solids content (SSC) of fresh jujube using near-infrared (NIR) spectroscopy technique. Fresh jujube samples were collected in different areas of Taigu and Taiyuan cities, central China in ...

Experts' understanding of partial derivatives using the Partial Derivative Machine

OpenAIRE

Roundy, David; Dorko, Allison; Dray, Tevian; Manogue, Corinne A.; Weber, Eric

2014-01-01

Partial derivatives are used in a variety of different ways within physics. Most notably, thermodynamics uses partial derivatives in ways that students often find confusing. As part of a collaboration with mathematics faculty, we are at the beginning of a study of the teaching of partial derivatives, a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. As a part of this project, we have performed a pilot study of expert understanding...

Coupling of albumin flux to volume flow in skin and muscles of anesthetized rats

International Nuclear Information System (INIS)

Renkin, E.M.; Gustafson-Sgro, M.; Sibley, L.

1988-01-01

Bovine serum albumin (BSA) labeled with 131 I or 125 I was injected intravenously in pentobarbital sodium-anesthetized rats, and tracer clearances into leg skin and muscles were measured over 30, 60, and 120 min. BSA labeled with the alternate tracer was used as vascular volume reference. Two minutes before injection of the tracer, a ligature was tied around one femoral vein to occlude outflow partially and raise capillary pressure in that leg. The unoccluded leg served as control. Skin and muscles of the occluded leg had variably and substantially higher water contents (delta W) than paired control tissues and slightly but consistently increased albumin clearances (CA). The delta CA/delta W, equivalent to the albumin concentration of capillary filtrate relative to plasma determined by linear regression, were as follows: leg skin 0.004 (95% confidence limits -0.001 to +0.009), muscle biceps femoris 0.005 (0.001-0.010), muscle gastrocnemius 0.011 (0.004-0.019), muscle tibialis anterior 0.016 (0.012-0.021). All these values are significantly less than 0.10, which corresponds to a reflection coefficient for serum albumin (sigma A) of 0.90. Convective coupling of albumin flux to volume flux in skin and muscles of intact, anesthetized rats is low, with sigma AS in the range 0.98 to greater than 0.99

A graphical method to evaluate spectral preprocessing in multivariate regression calibrations: example with Savitzky-Golay filters and partial least squares regression.

Science.gov (United States)

Delwiche, Stephen R; Reeves, James B

2010-01-01

In multivariate regression analysis of spectroscopy data, spectral preprocessing is often performed to reduce unwanted background information (offsets, sloped baselines) or accentuate absorption features in intrinsically overlapping bands. These procedures, also known as pretreatments, are commonly smoothing operations or derivatives. While such operations are often useful in reducing the number of latent variables of the actual decomposition and lowering residual error, they also run the risk of misleading the practitioner into accepting calibration equations that are poorly adapted to samples outside of the calibration. The current study developed a graphical method to examine this effect on partial least squares (PLS) regression calibrations of near-infrared (NIR) reflection spectra of ground wheat meal with two analytes, protein content and sodium dodecyl sulfate sedimentation (SDS) volume (an indicator of the quantity of the gluten proteins that contribute to strong doughs). These two properties were chosen because of their differing abilities to be modeled by NIR spectroscopy: excellent for protein content, fair for SDS sedimentation volume. To further demonstrate the potential pitfalls of preprocessing, an artificial component, a randomly generated value, was included in PLS regression trials. Savitzky-Golay (digital filter) smoothing, first-derivative, and second-derivative preprocess functions (5 to 25 centrally symmetric convolution points, derived from quadratic polynomials) were applied to PLS calibrations of 1 to 15 factors. The results demonstrated the danger of an over reliance on preprocessing when (1) the number of samples used in a multivariate calibration is low (<50), (2) the spectral response of the analyte is weak, and (3) the goodness of the calibration is based on the coefficient of determination (R(2)) rather than a term based on residual error. The graphical method has application to the evaluation of other preprocess functions and various

Influence of free water content on the compressive mechanical ...

Indian Academy of Sciences (India)

tars with different water content, the upward section of the stress–strain curve ..... Recent work by Zhou & Hao (2008) also provide computational confirmation ... these volume change may be closely related to micro-capillarity action in the ...

High Volume Manufacturing and Field Stability of MEMS Products

Science.gov (United States)

Martin, Jack

Low volume MEMS/NEMS production is practical when an attractive concept is implemented with business, manufacturing, packaging, and test support. Moving beyond this to high volume production adds requirements on design, process control, quality, product stability, market size, market maturity, capital investment, and business systems. In a broad sense, this chapter uses a case study approach: It describes and compares the silicon-based MEMS accelerometers, pressure sensors, image projection systems, and gyroscopes that are in high volume production. Although they serve several markets, these businesses have common characteristics. For example, the manufacturing lines use automated semiconductor equipment and standard material sets to make consistent products in large quantities. Standard, well controlled processes are sometimes modified for a MEMS product. However, novel processes that cannot run with standard equipment and material sets are avoided when possible. This reliance on semiconductor tools, as well as the organizational practices required to manufacture clean, particle-free products partially explains why the MEMS market leaders are integrated circuit manufacturers. There are other factors. MEMS and NEMS are enabling technologies, so it can take several years for high volume applications to develop. Indeed, market size is usually a strong function of price. This becomes a vicious circle, because low price requires low cost - a result that is normally achieved only after a product is in high volume production. During the early years, IC companies reduced cost and financial risk by using existing facilities for low volume MEMS production. As a result, product architectures are partially determined by capabilities developed for previous products. This chapter includes a discussion of MEMS product architecture with particular attention to the impact of electronic integration, packaging, and surfaces. Packaging and testing are critical, because they are

Quantifying Rock Weakening Due to Decreasing Calcite Mineral Content by Numerical Simulations.

Science.gov (United States)

Wetzel, Maria; Kempka, Thomas; Kühn, Michael

2018-04-01

The quantification of changes in geomechanical properties due to chemical reactions is of paramount importance for geological subsurface utilisation, since mineral dissolution generally reduces rock stiffness. In the present study, the effective elastic moduli of two digital rock samples, the Fontainebleau and Bentheim sandstones, are numerically determined based on micro-CT images. Reduction in rock stiffness due to the dissolution of 10% calcite cement by volume out of the pore network is quantified for three synthetic spatial calcite distributions (coating, partial filling and random) using representative sub-cubes derived from the digital rock samples. Due to the reduced calcite content, bulk and shear moduli decrease by 34% and 38% in maximum, respectively. Total porosity is clearly the dominant parameter, while spatial calcite distribution has a minor impact, except for a randomly chosen cement distribution within the pore network. Moreover, applying an initial stiffness reduced by 47% for the calcite cement results only in a slightly weaker mechanical behaviour. Using the quantitative approach introduced here substantially improves the accuracy of predictions in elastic rock properties compared to general analytical methods, and further enables quantification of uncertainties related to spatial variations in porosity and mineral distribution.

Estimation of active pharmaceutical ingredients content using locally weighted partial least squares and statistical wavelength selection.

OpenAIRE

Kim, Sanghong; Kano, Manabu; Nakagawa, Hiroshi; Hasebe, Shinji

2011-01-01

Development of quality estimation models using near infrared spectroscopy (NIRS) and multivariate analysis has been accelerated as a process analytical technology (PAT) tool in the pharmaceutical industry. Although linear regression methods such as partial least squares (PLS) are widely used, they cannot always achieve high estimation accuracy because physical and chemical properties of a measuring object have a complex effect on NIR spectra. In this research, locally weighted PLS (LW-PLS) wh...

Statistical representative elementary volumes of porous media determined using greyscale analysis of 3D tomograms

Science.gov (United States)

Bruns, S.; Stipp, S. L. S.; Sørensen, H. O.

2017-09-01

Digital rock physics carries the dogmatic concept of having to segment volume images for quantitative analysis but segmentation rejects huge amounts of signal information. Information that is essential for the analysis of difficult and marginally resolved samples, such as materials with very small features, is lost during segmentation. In X-ray nanotomography reconstructions of Hod chalk we observed partial volume voxels with an abundance that limits segmentation based analysis. Therefore, we investigated the suitability of greyscale analysis for establishing statistical representative elementary volumes (sREV) for the important petrophysical parameters of this type of chalk, namely porosity, specific surface area and diffusive tortuosity, by using volume images without segmenting the datasets. Instead, grey level intensities were transformed to a voxel level porosity estimate using a Gaussian mixture model. A simple model assumption was made that allowed formulating a two point correlation function for surface area estimates using Bayes' theory. The same assumption enables random walk simulations in the presence of severe partial volume effects. The established sREVs illustrate that in compacted chalk, these simulations cannot be performed in binary representations without increasing the resolution of the imaging system to a point where the spatial restrictions of the represented sample volume render the precision of the measurement unacceptable. We illustrate this by analyzing the origins of variance in the quantitative analysis of volume images, i.e. resolution dependence and intersample and intrasample variance. Although we cannot make any claims on the accuracy of the approach, eliminating the segmentation step from the analysis enables comparative studies with higher precision and repeatability.

Preoperative Single Fraction Partial Breast Radiotherapy for Early-Stage Breast Cancer

Energy Technology Data Exchange (ETDEWEB)

Palta, Manisha; Yoo, Sua; Adamson, Justus D.; Prosnitz, Leonard R. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Horton, Janet K., E-mail: janet.horton@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

2012-01-01

Purpose: Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. Methods and Materials: A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A 'virtual plan' was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. Results: The median breast volume was 1,713 cm{sup 3} (range: 1,014-2,140), and the median clinical target volume was 44 cm{sup 3} (range: 26-73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70-1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2-6.9) and 13.3% (range: 7.5-20.8) compared with 18% (range: 3-42) and 53% (range: 24-65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm{sup 3} of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Conclusion: Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing.

Preoperative single fraction partial breast radiotherapy for early-stage breast cancer.

Science.gov (United States)

Palta, Manisha; Yoo, Sua; Adamson, Justus D; Prosnitz, Leonard R; Horton, Janet K

2012-01-01

Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A "virtual plan" was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. The median breast volume was 1,713 cm(3) (range: 1,014-2,140), and the median clinical target volume was 44 cm(3) (range: 26-73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70-1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2-6.9) and 13.3% (range: 7.5-20.8) compared with 18% (range: 3-42) and 53% (range: 24-65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm(3) of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing. Copyright © 2012 Elsevier Inc. All rights reserved.

Preoperative Single Fraction Partial Breast Radiotherapy for Early-Stage Breast Cancer

International Nuclear Information System (INIS)

Palta, Manisha; Yoo, Sua; Adamson, Justus D.; Prosnitz, Leonard R.; Horton, Janet K.

2012-01-01

Purpose: Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. Methods and Materials: A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A “virtual plan” was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. Results: The median breast volume was 1,713 cm 3 (range: 1,014–2,140), and the median clinical target volume was 44 cm 3 (range: 26–73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70–1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2–6.9) and 13.3% (range: 7.5–20.8) compared with 18% (range: 3–42) and 53% (range: 24–65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm 3 of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Conclusion: Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing.

Kinetics of hydrothermally induced transformation of yttria partially stabilized zirconia

International Nuclear Information System (INIS)

Payyapilly, J.J.; Butt, D.P.

2007-01-01

Yttria-stabilized zirconia undergoes tetragonal to monoclinic phase transformation under hydrothermal conditions in the temperature range of 150-350 deg. C. Phase transformation accompanied by volume change in bulk yttria partially stabilized zirconia (YPSZ) leads to micro-cracking, loss of mechanical integrity and ultimately disintegration. The mechanical properties of the bulk YPSZ material deteriorate with the amount of the phase transformation and in some cases catastrophic failure are observed. The phase transformation is analyzed using macroscopic and microscopic techniques. X-ray diffraction data is used to quantify the phase transformation in bulk material. Kinetics of the phase transformation is studied at various temperatures

2013 CIME Course Vector-valued Partial Differential Equations and Applications

CERN Document Server

Marcellini, Paolo

2017-01-01

Collating different aspects of Vector-valued Partial Differential Equations and Applications, this volume is based on the 2013 CIME Course with the same name which took place at Cetraro, Italy, under the scientific direction of John Ball and Paolo Marcellini. It contains the following contributions: The pullback equation (Bernard Dacorogna), The stability of the isoperimetric inequality (Nicola Fusco), Mathematical problems in thin elastic sheets: scaling limits, packing, crumpling and singularities (Stefan Müller), and Aspects of PDEs related to fluid flows (Vladimir Sverák). These lectures are addressed to graduate students and researchers in the field.

Some physico-chemical properties and mineral contents of sweet ...

African Journals Online (AJOL)

STORAGESEVER

2009-06-17

Jun 17, 2009 ... contents of sweet cherry (Prunus avium L.) type grown in Konya .... Working conditions of ICP-AES. Instrument: ICP-AES ... The volume of fruit (V) and fruit density (Pt), were determined using the liquid ... These differences can.

Direct liquid content measurement applicable for He II space cryostats

International Nuclear Information System (INIS)

Wanner, M.

1988-01-01

A direct calorimetric method for content measurement in the He II cryostat ISO was assessed. A well defined heat pulse into the He II bath causes a small temperature increase which can be measured and directly correlated to the liquid mass through the He II specific heat. To study this method under the potential zero gravity constraints of disconnected liquid volumes a setup was established for investigating heat transfer between separated liquid volumes. The results for different fluid configurations confirm that even for completely disconnected volumes the heat is almost immediately distributed throughout the whole liquid by evaporation and recondensation

An Improved Method for Determination of Cyanide Content in Bitter Almond Oil.

Science.gov (United States)

Chen, Jia; Liu, Lei; Li, Mengjun; Yu, Xiuzhu; Zhang, Rui

2018-01-01

An improved colorimetric method for determination of cyanide content in bitter almond oil was developed. The optimal determination parameters were as follows: volume ratio of hydrochloric acid to bitter almond oil (v/v), 1.5:1; holding time for hydrolysis, 120 min; and volume ratio of distillation solution to bitter almond oil (v/v), 8:1. Analytical results showed that the relative standard deviations (SDs) of determinations were less than 10%, which satisfies the test requirements. The results of high-performance liquid chromatography and measurements exhibited a significant correlation (R = 0.9888, SD = 0.2015). Therefore, the improved colorimetric method can be used to determine cyanide content in bitter almond oil.

TechTrends 2010-2015: A Content Analysis

Science.gov (United States)

Stauffer, Eric

2017-01-01

This study is a content analysis of articles published within the journal "TechTrends" from 2000 to 2015. The study reveals that the publication "TechTrends" has increased the overall number of peer reviewed original papers over the last 6 years. The author describes the proportion of these original papers per volume and…

Repaired tetralogy of Fallot with coexisting unrepaired partial anomalous pulmonary venous connection is associated with diminished right ventricular ejection fraction and more severe right ventricular dilation

International Nuclear Information System (INIS)

Chan, Sherwin S.; Whitehead, Kevin K.; Kim, Timothy S.; Fu, Gregory L.; Fogel, Mark A.; Harris, Matthew A.; Keller, Marc S.

2015-01-01

There is an established association between tetralogy of Fallot and partial anomalous pulmonary venous connections. This association is important because surgically repaired tetralogy patients have increased risk of right heart failure. We hypothesize that partial anomalous venous connections increase right ventricular volumes and worsen right ventricular failure. We reviewed cardiac MRI exams performed at a tertiary pediatric hospital from January 2005 to January 2014. We identified patients with repaired tetralogy and unrepaired partial anomalous pulmonary venous connection. We used age- and gender-matched repaired tetralogy patients without partial anomalous pulmonary venous connection as controls. We analyzed the MRI results and surgical course and performed comparative statistics to identify group differences. There were eight patients with repaired tetralogy and unrepaired partial anomalous pulmonary venous connection and 16 controls. In all cases, the partial anomalous pulmonary venous connection was not detected on preoperative echocardiography. There were no significant differences in surgical course and body surface area between the two groups. Repaired tetralogy patients with unrepaired partial anomalous pulmonary venous connection showed significantly higher indexed right ventricular end diastolic volume (149 ± 33 mL/m 2 vs. 118 ± 30 mL/m 2 ), right ventricle to left ventricle size ratios (3.1 ± 1.3 vs. 1.9 ± 0.5) and a higher incidence of reduced right ventricular ejection fraction compared to controls (3/8 vs. 0/16). Repaired tetralogy of Fallot with unrepaired partial anomalous pulmonary venous connection is associated with reduced right ventricular ejection fraction and more significant right ventricular dilation. (orig.)

Repaired tetralogy of Fallot with coexisting unrepaired partial anomalous pulmonary venous connection is associated with diminished right ventricular ejection fraction and more severe right ventricular dilation

Energy Technology Data Exchange (ETDEWEB)

Chan, Sherwin S. [Children' s Mercy Hospital and Clinics, Department of Radiology, Kansas City, MO (United States); Whitehead, Kevin K.; Kim, Timothy S.; Fu, Gregory L.; Fogel, Mark A.; Harris, Matthew A. [Children' s Hospital of Philadelphia, Department of Cardiology, Philadelphia, PA (United States); Keller, Marc S. [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

2015-09-15

There is an established association between tetralogy of Fallot and partial anomalous pulmonary venous connections. This association is important because surgically repaired tetralogy patients have increased risk of right heart failure. We hypothesize that partial anomalous venous connections increase right ventricular volumes and worsen right ventricular failure. We reviewed cardiac MRI exams performed at a tertiary pediatric hospital from January 2005 to January 2014. We identified patients with repaired tetralogy and unrepaired partial anomalous pulmonary venous connection. We used age- and gender-matched repaired tetralogy patients without partial anomalous pulmonary venous connection as controls. We analyzed the MRI results and surgical course and performed comparative statistics to identify group differences. There were eight patients with repaired tetralogy and unrepaired partial anomalous pulmonary venous connection and 16 controls. In all cases, the partial anomalous pulmonary venous connection was not detected on preoperative echocardiography. There were no significant differences in surgical course and body surface area between the two groups. Repaired tetralogy patients with unrepaired partial anomalous pulmonary venous connection showed significantly higher indexed right ventricular end diastolic volume (149 ± 33 mL/m{sup 2} vs. 118 ± 30 mL/m{sup 2}), right ventricle to left ventricle size ratios (3.1 ± 1.3 vs. 1.9 ± 0.5) and a higher incidence of reduced right ventricular ejection fraction compared to controls (3/8 vs. 0/16). Repaired tetralogy of Fallot with unrepaired partial anomalous pulmonary venous connection is associated with reduced right ventricular ejection fraction and more significant right ventricular dilation. (orig.)

Supplementation with partially hydrogenated oil in grazing dairy cows in early lactation.

Science.gov (United States)

Schroeder, G F; Gagliostro, G A; Becu-Villalobos, D; Lacau-Mengido, I

2002-03-01

Effects of partially hydrogenated oil on performance, loss of body weight and body condition score, and blood metabolite and hormone concentrations were evaluated in 37 multiparous Holstein cows in grazing conditions during the first 100 d of lactation. Six additional Holstein cows, each fitted with a ruminal cannula, were allocated to a replicated 3 x 3 Latin square to evaluate effects of supplemental fat on rumen environment and pasture digestion. All cows grazed mixed pastures based on alfalfa (Medicago sativa) and orchardgrass (Dactylis glomerata L.) and received 5.4 kg/d of a basal concentrate to which 0, 0.5, or 1 kg/cow per day of partially hydrogenated oil (melting point 58 to 60 degrees C) containing 30.3, 34.9, 21.8, and 3.3% of C16:0, C18:0, C18:1, and C182, respectively, was added. Feeding 1 kg/d of supplemental fat increased fat-corrected milk from 23.4 to 26.3 kg/d, milk fat content from 3.44 to 3.78%, and milk fat yield from 0.87 to 1.03 kg/d compared to control. Milk protein percentage and yield were not affected. Cows fed 1 kg/d of fat increased the content and yield of C16:0 and C18:0 in milk compared with cows fed no added oil. Dry matter intake (DMI) from pasture decreased from 17.8 kg/d for control cows to 13.6 kg/d for cows fed 1 kg of oil, whereas DMI from concentrate was higher for cows fed 1 kg/d of fat (6.0 kg/d) than for controls (5.2 kg/d). Supplemental fat did not affect total dry matter or estimated energy intake and did not change losses of body weight or body condition scores. Plasma concentrations of nonesterified fatty acids, insulin, somatotrophin, and insulin-like growth factor-I did not differ among treatments. Concentration of plasma triglycerides was lowered from 318.5 to 271.2 mg/dl, whereas plasma cholesterol was elevated from 185.0 to 235.8 mg/dl in cows receiving 1 kg/d of supplemental fat compared with controls. Responses to lipolytic or insulin challenges were not affected by feeding oil. Supplemental fat did not affect

Content Analysis of the "Professional School Counseling" Journal: The First Ten Years

Science.gov (United States)

Falco, Lia D.; Bauman, Sheri; Sumnicht, Zachary; Engelstad, Alicia

2011-01-01

The authors conducted a content analysis of the articles published in the first 10 volumes of the "Professional School Counseling" (PSC) journal, beginning in October 1997 when "The School Counselor" merged with "Elementary School Counseling and Guidance". The analysis coded a total of 571 articles into 20 content categories. Findings address the…

Workshop on Recent Trends in Complex Methods for Partial Differential Equations

CERN Document Server

Celebi, A; Tutschke, Wolfgang

1999-01-01

This volume is a collection of manscripts mainly originating from talks and lectures given at the Workshop on Recent Trends in Complex Methods for Par­ tial Differential Equations held from July 6 to 10, 1998 at the Middle East Technical University in Ankara, Turkey, sponsored by The Scientific and Tech­ nical Research Council of Turkey and the Middle East Technical University. This workshop is a continuation oftwo workshops from 1988 and 1993 at the In­ ternational Centre for Theoretical Physics in Trieste, Italy entitled Functional analytic Methods in Complex Analysis and Applications to Partial Differential Equations. Since classical complex analysis of one and several variables has a long tra­ dition it is of high level. But most of its basic problems are solved nowadays so that within the last few decades it has lost more and more attention. The area of complex and functional analytic methods in partial differential equations, however, is still a growing and flourishing field, in particular as these ...

Volume loss as a tool to assess kiln drying of eucalyptus wood

Directory of Open Access Journals (Sweden)

Djeison Cesar Batista

Full Text Available In this study, we aimed to analyze the kiln drying quality of Eucalyptus grandis, Eucalyptus saligna and Eucalyptus dunnii woods with respect to volume loss. Wood from the three species was kiln dried together with the same drying schedule and conditions in a conventional-temperature pilot kiln. Three kinds of volume loss were evaluated: total - from saturated (initial to machined (final condition; shrinkage - from saturated to 10% moisture content; and machining - from 10% moisture content to machined condition. Eucalyptus grandis wood was the most dimensionally stable and presented the smallest volume loss due to shrinkage. Although they had different shrinkage behaviors, Eucalyptus grandis and Eucalyptus saligna woods presented the same drying quality regarding machining and total volume losses. These species can be considered the same for kiln drying. Eucalyptus dunnii wood presented the worst quality in drying, and should not be kiln dried in the same batch with the other species.

Type-Directed Partial Evaluation

DEFF Research Database (Denmark)

Danvy, Olivier

1998-01-01

Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML...

Type-Directed Partial Evaluation