Defining optimal tracer activities in pediatric oncologic whole-body "1"8F-FDG-PET/MRI

International Nuclear Information System (INIS)

Gatidis, Sergios; Schmidt, Holger; Nikolaou, Konstantin; Schwenzer, Nina F.; Schaefer, Juergen F.; La Fougere, Christian

2016-01-01

To explore the feasibility of reducing administered tracer activities and to assess optimal activities for combined "1"8F-FDG-PET/MRI in pediatric oncology. 30 "1"8F-FDG-PET/MRI examinations were performed on 24 patients with known or suspected solid tumors (10 girls, 14 boys, age 12 ± 5.6 [1-18] years; PET scan duration: 4 min per bed position). Low-activity PET images were retrospectively simulated from the originally acquired data sets using randomized undersampling of list mode data. PET data of different simulated administered activities (0.25-2.5 MBq/kg body weight) were reconstructed with or without point spread function (PSF) modeling. Mean and maximum standardized uptake values (SUV_m_e_a_n and SUV_m_a_x) as well as SUV variation (SUV_v_a_r) were measured in physiologic organs and focal FDG-avid lesions. Detectability of organ structures and of focal "1"8F-FDG-avid lesions as well as the occurrence of false-positive PET lesions were assessed at different simulated tracer activities. Subjective image quality steadily declined with decreasing tracer activities. Compared to the originally acquired data sets, mean relative deviations of SUV_m_e_a_n and SUV_m_a_x were below 5 % at "1"8F-FDG activities of 1.5 MBq/kg or higher. Over 95 % of anatomic structures and all pathologic focal lesions were detectable at 1.5 MBq/kg "1"8F-FDG. Detectability of anatomic structures and focal lesions was significantly improved using PSF. No false-positive focal lesions were observed at tracer activities of 1 MBq/kg "1"8F-FDG or higher. Administration of "1"8F-FDG activities of 1.5 MBq/kg is, thus, feasible without obvious diagnostic shortcomings, which is equivalent to a dose reduction of more than 50 % compared to current recommendations. Significant reduction in administered "1"8F-FDG tracer activities is feasible in pediatric oncologic PET/MRI. Appropriate activities of "1"8F-FDG or other tracers for specific clinical questions have to be further established in selected

[Protein losing enteropathy (PLE) detected by Tc99m-labelled human serum albumin abdominal scintigraphy--case report].

Science.gov (United States)

Hubalewska-Hoła, Alicja; Sowa-Staszczak, Anna; Szczerbiński, Tomasz; Lis, Grzegorz; Huszno, Bohdan; Szybiński, Zbigniew

2003-01-01

Protein losing enteropathy (PLE) is a gastrointestinal disorder that is associated with excessive loss of plasma protein into the gut resulting from abnormal mucosal permeability. The disease is usually caused by inflammation. The loss of protein in PLE is a nonselective process affecting albumin, globulin and transferrin. Abdominal scintigraphy with human serum albumin marked by Tc99m seems to be an easy and sensitive method for diagnosing PLE. An 4-year-old girl was presented to an outside Pediatric Department due to hypoproteinemia and recurrent pneumonia which had caused several prior hospitalizations. The laboratory tests revealed hypoproteinemia, hypoalbuminemia, low level of IgG, sideropenia, and a decreased level of T lymphocytes. The loss of protein into the gut was confirmed by fecal clearance of alfa-1 antitrypsin. Only nonspecific inflammation was detected by biopsy of the small intestine. These clinical and laboratory findings, quickly decreasing IgG and albumin levels in spite of i.v. supplementation and the lack of proteinuria permitted PLE diagnosis. The abdominal scintigraphy was planned to assess and localise protein losing through GIT and for strategy of possible surgical treatment. Abdominal dynamic scintigraphy was performed immediately after the injection of 300 MBq Tc99m human albumin. 90 images were taken within 180 minutes. Delayed abdominal images were obtained 6 and 24 hours after the tracer injection. Anterior abdominal scintigraphy showed pathological activity of Tc99m-albumin in small bowel in the upper left segment of the abdomen in the 40th minute after injection. Extensive accumulation of albumin was seen in the 160th minute. Delayed images, after 3 and 6 hours, revealed translocation of the tracer into the lower right abdominal segment. The further passage and tracer concentration was detected in ascendant and transverse colon. Based on the laboratory tests and scintigraphic images the girl was suspected to have segmental

The effects of surface condition on abdominal muscle activity during single-legged hold exercise.

Science.gov (United States)

Ha, Sung-min; Oh, Jae-seop; Jeon, In-cheol; Kwon, Oh-yun

2015-02-01

To treat low-back pain, various spinal stability exercises are commonly used to improve trunk muscle function and strength. Because human movement for normal daily activity occurs in multi-dimensions, the importance of exercise in multi-dimensions or on unstable surfaces has been emphasized. Recently, a motorized rotating platform (MRP) for facilitating multi-dimensions dynamic movement was introduced for clinical use. However, the abdominal muscle activity with this device has not been reported. The purpose of this study was to compare the abdominal muscle activity (rectus abdominis, external and internal oblique muscles) during an active single-leg-hold (SLH) exercise on a floor (stable surface), foam roll, and motorized rotating platform (MRP). Thirteen healthy male subjects participated in this study. Using electromyography, the abdominal muscle activity was measured while the subjects performed SLH exercises on floor (stable surface), foam roll, and MRP. There were significant differences in the abdominal muscle activities among conditions (P.05) (Fig. 2). After the Bonferroni correction, however, no significant differences among conditions remained, except for differences in both side IO muscle activity between the floor and foam roll conditions (padjexercises on a foam roll and MRP is more effective increased activities of both side of RA and IO, and Rt. EO compared to floor condition. However, there were no significant differences in abdominal muscles activity in the multiple comparison between conditions (mean difference were smaller than the standard deviation in the abdominal muscle activities) (padj>0.017), except for differences in both side IO muscle activity between the floor (stable surface) and foam roll (padj<0.017) (effect size: 0.79/0.62 (non-supporting/supporting leg) for foam-roll versus floor). Copyright © 2014 Elsevier Ltd. All rights reserved.

FIBRINOLYTIC-ACTIVITY IN THE ABDOMINAL-CAVITY OF RATS WITH FECAL PERITONITIS

NARCIS (Netherlands)

van Goor, Harry; de Graaf, JS; Sluiter, WJ; van der Meer, J; Bom, VJJ; Bleichrodt, RP

Generalized peritonitis causes a reduction in abdominal fibrinolytic activity, resulting in persistence of intraabdominal fibrin with subsequent adhesion and abscess formation. The activities of tissue plasminogen activator (tPA) and plasminogen activator inhibitor (PAI) were measured in the

Simultaneous 3D tracking of passive tracers and microtubule bundles in an active gel

Science.gov (United States)

Fan, Yi; Breuer, Kenneth S.; Fluids Team

Kinesin-driven microtubule bundles generate a spontaneous flow in unconfined geometries. They exhibit properties of active matter, including the emergence of collective motion, reduction of apparent viscosity and consumption of local energy. Here we present results from 3D tracking of passive tracers (using Airy rings and 3D scanning) synchronized with 3D measurement of the microtubule bundles motion. This technique is applied to measure viscosity variation and collective flow in a confined geometry with particular attention paid to the self-pumping system recently reported by Wu et al. (2016). Results show that the viscosity in an equilibrium microtubule network is around half that of the isotropic unbundled microtubule solution. Cross-correlations of the active microtubule network and passive tracers define a neighborhood around microtubule bundles in which passive tracers are effectively transported. MRSEC NSF.

Development of radioisotope tracer technology

International Nuclear Information System (INIS)

Jin, Joon Ha; Lee, Myun Joo; Jung, Sung Hee; Park, Soon Chul; Lim, Dong Soon; Kim, Jae Ho; Lee, Jae Choon; Lee, Doo Sung; Cho, Yong Suk; Shin, Sung Kuan

2000-04-01

The purpose of this study is to develop the radioisotope tracer technology, which can be used in solving industrial and environmental problems and to build a strong tracer group to support the local industries. In relation to the tracer technology in 1999, experiments to estimate the efficiencies of a sludge digester of a waste water treatment plant and a submerged biological reactor of a dye industry were conducted. As a result, the tracer technology for optimization of facilities related to wastewater treatment has been developed and is believed to contribute to improve their operation efficiency. The quantification of the experimental result was attempted to improve the confidence of tracer technology by ECRIN program which basically uses the MCNP simulation principle. Using thin layer activation technique, wear of tappet shim was estimated. Thin layer surface of a tappet shim was irradiated by proton beam and the correlation between the measured activity loss and the amount of wear was established. The equipment was developed to adjust the energy of proton which collides with the surface of tappet. The tracer project team has participated into the tracer test for estimating the efficiency of RFCC system in SK cooperation. From the experiment the tracer team has obtained the primary elements to be considered for judging the efficiency of RFCC unit. By developing the tracer techniques to test huge industrial units like RFCC, the tracer team will be able to support the local industries that require technical services to solve any urgent trouble. (author)

Statistically Based Morphodynamic Modeling of Tracer Slowdown

Science.gov (United States)

Borhani, S.; Ghasemi, A.; Hill, K. M.; Viparelli, E.

2017-12-01

Tracer particles are used to study bedload transport in gravel-bed rivers. One of the advantages associated with using of tracer particles is that they allow for direct measures of the entrainment rates and their size distributions. The main issue in large scale studies with tracer particles is the difference between tracer stone short term and long term behavior. This difference is due to the fact that particles undergo vertical mixing or move to less active locations such as bars or even floodplains. For these reasons the average virtual velocity of tracer particle decreases in time, i.e. the tracer slowdown. In summary, tracer slowdown can have a significant impact on the estimation of bedload transport rate or long term dispersal of contaminated sediment. The vast majority of the morphodynamic models that account for the non-uniformity of the bed material (tracer and not tracer, in this case) are based on a discrete description of the alluvial deposit. The deposit is divided in two different regions; the active layer and the substrate. The active layer is a thin layer in the topmost part of the deposit whose particles can interact with the bed material transport. The substrate is the part of the deposit below the active layer. Due to the discrete representation of the alluvial deposit, active layer models are not able to reproduce tracer slowdown. In this study we try to model the slowdown of tracer particles with the continuous Parker-Paola-Leclair morphodynamic framework. This continuous, i.e. not layer-based, framework is based on a stochastic description of the temporal variation of bed surface elevation, and of the elevation specific particle entrainment and deposition. Particle entrainment rates are computed as a function of the flow and sediment characteristics, while particle deposition is estimated with a step length formulation. Here we present one of the first implementation of the continuum framework at laboratory scale, its validation against

Abdominal muscle activity during a standing long jump.

Science.gov (United States)

Okubo, Yu; Kaneoka, Koji; Shiina, Itsuo; Tatsumura, Masaki; Miyakawa, Shumpei

2013-08-01

Experimental laboratory study. To measure the activation patterns (onset and magnitude) of the abdominal muscles during a standing long jump using wire and surface electromyography. Activation patterns of the abdominal muscles, especially the deep muscles such as the transversus abdominis (TrA), have yet to be examined during full-body movements such as jumping. Thirteen healthy men participated. Wire electrodes were inserted into the TrA with the guidance of ultrasonography, and surface electrodes were attached to the skin overlying the rectus abdominis (RA) and external oblique (EO). Electromyographic signals and video images were recorded while each subject performed a standing long jump. The jump task was divided into 3 phases: preparation, push-off, and float. For each muscle, activation onset relative to the onset of the RA and normalized muscle activation levels (percent maximum voluntary contraction) were analyzed during each phase. Comparisons between muscles and phases were assessed using 2-way analyses of variance. The onset times of the TrA and EO relative to the onset of the RA were -0.13 ? 0.17 seconds and -0.02 ? 0.07 seconds, respectively. Onset of TrA activation was earlier than that of the EO. The activation levels of all 3 muscles were significantly greater during the push-off phase than during the preparation and float phases. Consistent with previously published trunk-perturbation studies in healthy persons, the TrA was activated prior to the RA and EO. Additionally, the highest muscle activation levels were observed during the push-off phase.

Development of positron tracer for in vivo estimation of brain MAO-B activity

International Nuclear Information System (INIS)

Inoue, Osamu; Tominaga, Toshiyoshi; Fukuda, Nobuo; Suzuki, Kazutoshi; Yamasaki, Toshio

1984-01-01

Both the specificity and the measurable range of enzyme activity of this method were found to be much dependent upon the enzymatic properties of substrate-tracer. The measurable range of brain enzyme activity was found to be from zero to the maximum value which was dependent upon two factors; the elimination rate of substratetracer from the brain (Ksub(el)) and the Vsub(max)/Ksub(m) value of substrate. The detectable range of changes in enzyme activity can be made wider by using another substrate as a tracer which has a lower Vsub(max)/Ksub(m) value or larger Ksub(el) value. The specificity can be also favorably designed by selection of substrate with various enzymatic or physico-chemical properties as a tracer. N, N-dimethyl phenylethylamine (DMPEA) was selected as a substrate-tracer for the estimation of brain MAO-B activity. Very high accumulation of radioactivity into mouse brain at 1 min after intravenous injection of 11 C-DMPEA, and a long-term retention of radioactivity in the brain were observed. 11 C-DMPEA seemed to be metabolized to 11 C-dimethylamine by brain MAO, and be trapped by the blood-brain barrier. When various dosage of 1-deprenyl (a specific MAO-B inhibitor) were pretreated, brain radioactivity at 1 hr after injection of 11 C-DMPEA significantly decreased in a dosage (1-deprenyl)-dependent way, while pretreatment with clorgyline (a specific MAO-A inhibitor) had no effect. This decrease in radioactivity might be due to the decrease of the production rate of labeled metabolite ( 11 C-dimethylamine) in the brain. The relationship between the radioactivity remaining at 1 hr after injection and MAO-B activity remaining in the brain was quite paralle. 11 C-DMPEA seems to be a specific radiotracer for the external detection of alterations in MAO-B activity in the brain with a fair sensitivity. (J.P.N.)

Leisure-time physical activity and intra-abdominal fat in young adulthood: A monozygotic co-twin control study.

Science.gov (United States)

Rottensteiner, Mirva; Leskinen, Tuija; Järvelä-Reijonen, Elina; Väisänen, Karoliina; Aaltonen, Sari; Kaprio, Jaakko; Kujala, Urho M

2016-05-01

To investigate differences in abdominal fat compartments between young adult monozygotic twin pairs discordant for leisure-time physical activity. Ten young adult male monozygotic twin pairs (age range 32-36 years) discordant for leisure-time physical activity during the past 3 years were systematically selected from a population-based Finnish twin cohort. Magnetic resonance image at the level of the L2-L3 intervertebral disc was used to predict intra-abdominal and subcutaneous abdominal fat masses. Dietary intake was assessed with a 4-day food diary. Inactive twins had 31% more intra-abdominal fat than their active co-twins (mean difference 0.52 kg, 95% CI 0.12 to 0.91, P = 0.016), whereas the difference in subcutaneous abdominal fat was only 13% (P = 0.21) and 3% in body mass index (P = 0.28). Intraperitoneal fat mass was 41% higher among inactive twins compared to their active co-twins (mean difference 0.41 kg, 95% CI 0.11 to 0.70, P = 0.012). Dietary intake did not differ between co-twins. A lower level of physical activity is related to greater accumulation of intra-abdominal fat among healthy adult males in their mid-30s. The findings highlight the importance of leisure-time physical activity independent of genes and diet in the prevention of intra-abdominal fat accumulation from early adulthood onward. © 2016 The Obesity Society.

Tracers and Tracer Testing: Design, Implementation, Tracer Selection, and Interpretation Methods

Energy Technology Data Exchange (ETDEWEB)

G. Michael Shook; Shannon L.; Allan Wylie

2004-01-01

Conducting a successful tracer test requires adhering to a set of steps. The steps include identifying appropriate and achievable test goals, identifying tracers with the appropriate properties, and implementing the test as designed. When these steps are taken correctly, a host of tracer test analysis methods are available to the practitioner. This report discusses the individual steps required for a successful tracer test and presents methods for analysis. The report is an overview of tracer technology; the Suggested Reading section offers references to the specifics of test design and interpretation.

Physical activity in adolescence and abdominal obesity in adulthood: a case-control study among women shift workers.

Science.gov (United States)

Garcez, Anderson da Silva; Olinto, Maria Teresa Anselmo; Canuto, Raquel; Olinto, Beatriz Anselmo; Pattussi, Marcos Pascoal; Paniz, Vera Maria Vieira

2015-01-01

Physical activity may have a protective effect against abdominal obesity, an important risk factor for cardiometabolic diseases. Thus, the aim of this study was to examine the association between the practice of physical activities in adolescence and abdominal obesity in adulthood among women shift workers in Southern Brazil in 2011. This case-control study included 215 cases (waist circumference greater than or equal to 88 cm) and 326 controls. For both the case and control groups, participation in leisure-time physical activities was most frequent in adolescence and was significantly less in adulthood. After adjusting for potential confounding factors, women who participated in five or more physical activities in adolescence were 50 percent less likely to have abdominal obesity than women who participated in one activity or no physical activities (Odds Ratio = 0.50; 95% confidential interval: 0.27-0.93, p value = .029). Participation in various types of leisure-time physical activities in adolescence may protect against abdominal obesity in adulthood, even if the number of physical activities decreases over time. This finding demonstrated the importance of physical activity as well as the period of life in which these should be encouraged for the prevention of health disorders, such as abdominal obesity.

Tracer studies with aortic infusion result in improper tracer distribution

International Nuclear Information System (INIS)

Wisneski, J.A.; Brooks, G.A.; Neese, R.A.; Stanley, W.C.; Morris, D.L.; Gertz, E.W.

1986-01-01

It has been suggested that lactate turnover can be accurately assessed by infusing radioactive lactate tracer into the aorta and sampling blood in the vena cava. However, there may be streaming of newly infused tracer in the aorta, resulting in a nonuniform arterial specific activity (SA). Furthermore vena caval blood may not be representative of mixed venous blood. The authors examined this problem in 7 anesthetized dogs with sampling catheters in the pulmonary (PA), carotid (CA), and femoral (FA) arteries, and the superior (SVC) and inferior (IVC) vena cavi. [1- 14 C]lactate was continuously infused into the left ventricle through a catheter introduced through the femoral artery. The same SA (dpm/μmol) was found in the CA and FA, indicating adequate mixing of newly infused tracer with trace. Three dogs showed differences between SVC, IVC and PA, suggesting a mixed venous sample can not be obtained from the VC. When the catheter was moved into the aorta, wide differences in SA appeared between the CA and FA, clearly reflecting streaming of tracer. These differences also appeared in the SVC and IVC. In conclusion, adequate mixing does not occur between tracer and trace in arterial blood with aortic infusion. Further, VC sampling will not give a consistent mixed venous SA. Therefore, for practical reasons, aortic tracer infusion with vena caval sampling will lead to erroneous turnover values

Effects of non-paretic arm exercises using a tubing band on abdominal muscle activity in stroke patients.

Science.gov (United States)

Lee, Dong-Kyu; Kang, Min-Hyeok; Kim, Ji-Won; Kim, Yang-Gon; Park, Ji-Hyuk; Oh, Jae-Seop

2013-01-01

Abdominal strengthening exercises are important for stroke patients; however, there is a lack of research on therapeutic exercises for increasing abdominal muscle activity in stroke patients. We investigated the effects of non-paretic arm exercises using a tubing band on abdominal muscle activity in stroke patients. In total, 18 hemiplegic subjects (13 males, 5 females) were recruited. All subjects performed non-paretic arm exercises involving three different shoulder movements (extension, flexion, and horizontal abduction) using an elastic tubing band. Surface electromyography (EMG) signals were recorded from the rectus abdominis (RA), external oblique (EO), and internal oblique (IO) muscles bilaterally during non-paretic arm exercises. EMG activities of abdominal muscles during non-paretic arm extension and horizontal abduction were increased significantly versus shoulder flexion when subjects performed the arm exercise in a seated position. Muscle activity of the EO was significantly greater in the paretic than the non-paretic side during non-paretic arm extension and horizontal abduction. We suggest that non-paretic arm extension and horizontal abduction exercises using an elastic tubing band may be effective in increasing abdominal muscle activity.

Obesity, abdominal obesity, physical activity, and caloric intake in US adults: 1988 to 2010.

Science.gov (United States)

Ladabaum, Uri; Mannalithara, Ajitha; Myer, Parvathi A; Singh, Gurkirpal

2014-08-01

Obesity and abdominal obesity are associated independently with morbidity and mortality. Physical activity attenuates these risks. We examined trends in obesity, abdominal obesity, physical activity, and caloric intake in US adults from 1988 to 2010. Univariate and multivariate analyses were performed using National Health and Nutrition Examination Survey data. Average body mass index (BMI) increased by 0.37% (95% confidence interval [CI], 0.30-0.44) per year in both women and men. Average waist circumference increased by 0.37% (95% CI, 0.30-0.43) and 0.27% (95% CI, 0.22-0.32) per year in women and men, respectively. The prevalence of obesity and abdominal obesity increased substantially, as did the prevalence of abdominal obesity among overweight adults. Younger women experienced the greatest increases. The proportion of adults who reported no leisure-time physical activity increased from 19.1% (95% CI, 17.3-21.0) to 51.7% (95% CI, 48.9-54.5) in women, and from 11.4% (95% CI, 10.0-12.8) to 43.5% (95% CI, 40.7-46.3) in men. Average daily caloric intake did not change significantly. BMI and waist circumference trends were associated with physical activity level but not caloric intake. The associated changes in adjusted BMIs were 8.3% (95% CI, 6.9-9.6) higher among women and 1.7% (95% CI, 0.68-2.8) higher among men with no leisure-time physical activity compared with those with an ideal level of leisure-time physical activity. Our analyses highlight important dimensions of the public health problem of obesity, including trends in younger women and in abdominal obesity, and lend support to the emphasis placed on physical activity by the Institute of Medicine. Copyright © 2014 Elsevier Inc. All rights reserved.

Obesity, Abdominal Obesity, Physical Activity, and Caloric Intake in U.S. Adults: 1988-2010

Science.gov (United States)

Ladabaum, Uri; Mannalithara, Ajitha; Myer, Parvathi A.; Singh, Gurkirpal

2014-01-01

Background Obesity and abdominal obesity are independently associated with morbidity and mortality. Physical activity attenuates these risks. We examined trends in obesity, abdominal obesity, physical activity, and caloric intake in U.S. adults from 1988 to 2010. Methods Univariate and multivariate analyses were performed using National Health and Nutrition Examination Survey (NHANES) data. Results Average body-mass index (BMI) increased by 0.37% (95% CI, 0.30-0.44%) per year in both women and men. Average waist circumference increased by 0.37% (95% CI, 0.30-0.43%) and 0.27% (95% CI, 0.22-0.32%) per year in women and men, respectively. The prevalence of obesity and abdominal obesity increased substantially, as did the prevalence of abdominal obesity among overweight adults. Younger women experienced the greatest increases. The proportion of adults who reported no leisure-time physical activity increased from 19.1% (95% CI, 17.3-21.0%) to 51.7% (95% CI, 48.9-54.5%) in women, and from 11.4% (95% CI, 10.0-12.8%) to 43.5% (95% CI, 40.7-46.3%) in men. Average daily caloric intake did not change significantly. BMI and waist circumference trends were associated with physical activity level, but not caloric intake. The associated changes in adjusted BMIs were 8.3% (95% CI, 6.9-9.6%) higher among women and 1.7% (95% CI, 0.68-2.8%) higher among men with no leisure-time physical activity compared to those with an ideal level of leisure-time physical activity. Conclusions Our analyses highlight important dimensions of the public health problem of obesity, including trends in younger women and in abdominal obesity, and lend support to the emphasis placed on physical activity by the Institute of Medicine. PMID:24631411

Preclinical Evaluation of RYM1, a Matrix Metalloproteinase-Targeted Tracer for Imaging Aneurysm.

Science.gov (United States)

Toczek, Jakub; Ye, Yunpeng; Gona, Kiran; Kim, Hye-Yeong; Han, Jinah; Razavian, Mahmoud; Golestani, Reza; Zhang, Jiasheng; Wu, Terence L; Jung, Jae-Joon; Sadeghi, Mehran M

2017-08-01

Matrix metalloproteinases (MMPs) play a key role in abdominal aortic aneurysm (AAA) development. Accordingly, MMP-targeted imaging provides important information regarding vessel wall biology in the course of aneurysm development. Given the small size of the vessel wall and its proximity with blood, molecular imaging of aneurysm optimally requires highly sensitive tracers with rapid blood clearance. To this end, we developed a novel hydrosoluble zwitterionic MMP inhibitor, RYM, on the basis of which a pan-MMP tracer, RYM1, was designed. Here, we describe the development and preclinical evaluation of RYM1 in comparison with RP805, a commonly used pan-MMP tracer in murine models of aneurysm. Methods: The macrocyclic hydroxamate-based pan-MMP inhibitor coupled with 6-hydrazinonicotinamide, RYM1, was synthesized and labeled with 99m Tc. Radiochemical stability of 99m Tc-RYM1 was evaluated by radio-high-performance liquid chromatography analysis. Tracer blood kinetics and biodistribution were compared with 99m Tc-RP805 in C57BL/6J mice ( n = 10). 99m Tc-RYM1 binding to aneurysm and specificity were evaluated by quantitative autoradiography in apolipoprotein E-deficient (apoE -/- ) mice with CaCl 2 -induced carotid aneurysm ( n = 11). Angiotensin II-infused apoE -/- ( n = 16) mice were used for small-animal SPECT/CT imaging. Aortic tissue MMP activity and macrophage marker CD68 expression were assessed by zymography and reverse-transcription polymerase chain reaction. Results: RYM1 showed nanomolar range inhibition constants for several MMPs. 99m Tc-RYM1 was radiochemically stable in mouse blood for 5 h and demonstrated rapid renal clearance and lower blood levels in vivo compared with 99m Tc-RP805. 99m Tc-RYM1 binding to aneurysm and its specificity were shown by autoradiography in carotid aneurysm. Angiotensin II infusion in apoE -/- mice for 4 wk resulted in AAA formation in 36% (4/11) of surviving animals. In vivo 99m Tc-RYM1 small-animal SPECT/CT images showed

The effects of therapeutic hip exercise with abdominal core activation on recruitment of the hip muscles.

Science.gov (United States)

Chan, Mandy Ky; Chow, Ka Wai; Lai, Alfred Ys; Mak, Noble Kc; Sze, Jason Ch; Tsang, Sharon Mh

2017-07-21

Core stabilization has been utilized for rehabilitation and prevention of lower limb musculoskeletal injuries. Previous studies showed that activation of the abdominal core muscles enhanced the hip muscle activity in hip extension and abduction exercises. However, the lack of the direct measurement and quantification of the activation level of the abdominal core muscles during the execution of the hip exercises affect the level of evidence to substantiate the proposed application of core exercises to promote training and rehabilitation outcome of the hip region. The aim of the present study was to examine the effects of abdominal core activation, which is monitored directly by surface electromyography (EMG), on hip muscle activation while performing different hip exercises, and to explore whether participant characteristics such as gender, physical activity level and contractile properties of muscles, which is assessed by tensiomyography (TMG), have confounding effect to the activation of hip muscles in enhanced core condition. Surface EMG of bilateral internal obliques (IO), upper gluteus maximus (UGMax), lower gluteus maximus (LGMax), gluteus medius (GMed) and biceps femoris (BF) of dominant leg was recorded in 20 young healthy subjects while performing 3 hip exercises: Clam, side-lying hip abduction (HABD), and prone hip extension (PHE) in 2 conditions: natural core activation (NC) and enhanced core activation (CO). EMG signals normalized to percentage of maximal voluntary isometric contraction (%MVIC) were compared between two core conditions with the threshold of the enhanced abdominal core condition defined as >20%MVIC of IO. Enhanced abdominal core activation has significantly promoted the activation level of GMed in all phases of clam exercise (P recruitment in Clam, HABD and PHE exercises, and this enhancement is correlated with higher physical activity and stiffer hip muscle. Our results suggest the potential application of abdominal core activation for

The difference between standing and sitting in 3 different seat inclinations on abdominal muscle activity and chest and abdominal expansion in woodwind and brass musicians

Directory of Open Access Journals (Sweden)

Bronwen Jane Ackermann

2014-08-01

Full Text Available Wind instrumentalists require a sophisticated functioning of their respiratory system to control their air stream, which provides the power for optimal musical performance. The air supply must be delivered into the instrument in a steady and controlled manner and with enough power by the action of the expiratory musculature to produce the desired level of sound at the correct pitch. It is suggested that playing posture may have an impact on the abdominal muscle activity controlling this expired air, but there is no research on musicians to support this theory. This study evaluated chest and abdominal expansion, via respiratory inductive plethysmography, as well as activation patterns of lower and upper abdominal musculature, using surface electromyography, during performance of a range of typical orchestral repertoire by 113 woodwind and brass players. Each of the five orchestral excerpts was played in one of four randomly allocated postures: standing; sitting flat; sitting inclined forwards; and sitting inclined backwards.Musicians showed a clear preference for playing in standing rather than sitting. In standing, the chest expansion range and maximum values were greater (p<0.01, while the abdominal expansion was less than in all sitting postures (p<0.01. Chest expansion patterns did not vary between the three sitting postures, while abdominal expansion was reduced in the forward inclined posture compared to the other sitting postures (p<0.05. There was no significant variation in abdominal muscle activation between the sitting postures, but the level of activation in sitting was only 2/3 of the significantly higher level observed in standing (p<0.01.This study has demonstrated significant differences in respiratory mechanics between sitting and standing postures in wind musicians during playing of typical orchestral repertoire. Further research is needed to clarify the complex respiratory mechanisms supporting musical performance.

Asian Tracer Experiment and Atmospheric Modeling (TEAM) Project: Draft Field Work Plan for the Asian Long-Range Tracer Experiment

Energy Technology Data Exchange (ETDEWEB)

Allwine, K Jerry; Flaherty, Julia E.

2007-08-01

This report provides an experimental plan for a proposed Asian long-range tracer study as part of the international Tracer Experiment and Atmospheric Modeling (TEAM) Project. The TEAM partners are China, Japan, South Korea and the United States. Optimal times of year to conduct the study, meteorological measurements needed, proposed tracer release locations, proposed tracer sampling locations and the proposed durations of tracer releases and subsequent sampling are given. Also given are the activities necessary to prepare for the study and the schedule for completing the preparation activities leading to conducting the actual field operations. This report is intended to provide the TEAM members with the information necessary for planning and conducting the Asian long-range tracer study. The experimental plan is proposed, at this time, to describe the efforts necessary to conduct the Asian long-range tracer study, and the plan will undoubtedly be revised and refined as the planning goes forward over the next year.

Dynamic dual-tracer PET reconstruction.

Science.gov (United States)

Gao, Fei; Liu, Huafeng; Jian, Yiqiang; Shi, Pengcheng

2009-01-01

Although of important medical implications, simultaneous dual-tracer positron emission tomography reconstruction remains a challenging problem, primarily because the photon measurements from dual tracers are overlapped. In this paper, we propose a simultaneous dynamic dual-tracer reconstruction of tissue activity maps based on guidance from tracer kinetics. The dual-tracer reconstruction problem is formulated in a state-space representation, where parallel compartment models serve as continuous-time system equation describing the tracer kinetic processes of dual tracers, and the imaging data is expressed as discrete sampling of the system states in measurement equation. The image reconstruction problem has therefore become a state estimation problem in a continuous-discrete hybrid paradigm, and H infinity filtering is adopted as the estimation strategy. As H infinity filtering makes no assumptions on the system and measurement statistics, robust reconstruction results can be obtained for the dual-tracer PET imaging system where the statistical properties of measurement data and system uncertainty are not available a priori, even when there are disturbances in the kinetic parameters. Experimental results on digital phantoms, Monte Carlo simulations and physical phantoms have demonstrated the superior performance.

Dual Tracer PET Imaging with FDG and FLT Differentiates Tuberculous Lymphadenopathy from Metastases in a Case of Carcinoma Cervix

Energy Technology Data Exchange (ETDEWEB)

Joshi, Prathamesh; Lele, Vikram; Aland, Parag; Gemawat, Shilpa [Jaslok Hospital and Research Centre, Woril (India)

2013-09-15

A forty-year-old woman with a known case of carcinoma cervix underwent 18-fluorodeoxyglucose positron emission tomography.computed tomography (18-FDG PET/CT) for evaluation of abdominal lymphadenopathy. Her treatment history included radical hysterectomy and radiotherapy 6 months ago. She complained of weight loss of 7 kg over last 5 months. The maximum intensity projection (MIP) image (Fig. 1a, arrows) revealed multiple areas of intense FDG uptake, which on CT and fused PET/CT images were localized to multiple lymph nodes in bilateral cervical region, right axilla, mediastinum and abdomen. The SUVmax of right axillary lymph nodes (most FDG avid of all lymph node groups) was 15.3. There was no evidence of metabolically active disease or CT demonstrable abnormality in rest of the body. Presence of metabolically active disease in extensive supradiaphramatic lymphadenopathy was unusual for a case of carcinoma cervix. This finding, along with history of significant weight loss and absence of extranodal disease, was suspicious for unrelated pathology like lymphoproliferative disorder or granulomatous disease. Mixed malignant and benign lymphadenopathy was also considered a possibility. To solve the conundrum, 18-fluoro-L-thymidine (FLT) PET/CT was performed on the next day. This scan was performed to assess the proliferation rate in various above-mentioned lymph nodes, and to plan the optimum site of biopsy. The FLT PET scan (Fig. 1b) showed physiological distribution of the tracer in bone marrow, liver, gall bladder and urinary bladder. There was minimal FLT uptake in the enlarged, FDG avid lymph nodes (Fig. 1c and d). SUVmax of FLT uptake in right axillary lymph nodes was 1.4 (SUVmax of FDG uptake = 15.8). The SUVmax of FLT uptake in cervical, mediastinal and abdominal lymph nodes were 1.3, 1.4 and 1.0 respectively. (SUVmax of FDG uptake 12.1, 12.7 and 11.9, respectively). Considering avidity for FDG and non-avidity of proliferation marker tracer (FLT), possibility of

Tracer techniques in microelectronics

International Nuclear Information System (INIS)

Flachowsky, J.; Freyer, K.

1981-01-01

Tracer technique and neutron activation analysis are capable of measuring impurities in semiconductor material or on the semiconductor surface in a very low concentration range. The methods, combined with autoradiography, are also suitable to determine dopant distributions in silicon. However, both techniques suffer from certain inherent experimental difficulties and/or limitations which are discussed. Methods of tracer technique practicable in the semiconductor field are described. (author)

Journal: Efficient Hydrologic Tracer-Test Design for Tracer ...

Science.gov (United States)

Hydrological tracer testing is the most reliable diagnostic technique available for the determination of basic hydraulic and geometric parameters necessary for establishing operative solute-transport processes. Tracer-test design can be difficult because of a lack of prior knowledge of the basic hydraulic and geometric parameters desired and the appropriate tracer mass to release. A new efficient hydrologic tracer-test design (EHTD) methodology has been developed to facilitate the design of tracer tests by root determination of the one-dimensional advection-dispersion equation (ADE) using a preset average tracer concentration which provides a theoretical basis for an estimate of necessary tracer mass. The method uses basic measured field parameters (e.g., discharge, distance, cross-sectional area) that are combined in functional relatipnships that descrive solute-transport processes related to flow velocity and time of travel. These initial estimates for time of travel and velocity are then applied to a hypothetical continuous stirred tank reactor (CSTR) as an analog for the hydrological-flow system to develop initial estimates for tracer concentration, tracer mass, and axial dispersion. Application of the predicted tracer mass with the hydraulic and geometric parameters in the ADE allows for an approximation of initial sample-collection time and subsequent sample-collection frequency where a maximum of 65 samples were determined to be necessary for descri

Abdominal obesity, TV-viewing time and prospective declines in physical activity

NARCIS (Netherlands)

Lakerveld, J.; Dunstan, D.W.; Bot, S.D.M.; Salmon, J.; Dekker, J.M.; Nijpels, G.; Owen, N.

2011-01-01

Objective: To examine the prospective associations of baseline abdominal obesity and TV-viewing time with five-year reductions in leisure-time physical activity level. Methods: We used data from the Australian Diabetes, Obesity and Lifestyle Study (AusDiab), a nationally representative

Tumoral tracers

International Nuclear Information System (INIS)

Camargo, E.E.

1979-01-01

Direct tumor tracers are subdivided in the following categories:metabolite tracers, antitumoral tracers, radioactive proteins and cations. Use of 67 Ga-citrate as a clinically important tumoral tracer is emphasized and gallium-67 whole-body scintigraphy is discussed in detail. (M.A.) [pt

Treatment of abdominal cellulite and circumference reduction with radiofrequency and dynamic muscle activation.

Science.gov (United States)

Wanitphakdeedecha, Rungsima; Iamphonrat, Thanawan; Thanomkitti, Kanchalit; Lektrakul, Nittaya; Manuskiatti, Woraphong

2015-01-01

Cellulite is a frequent skin condition for which treatment remains a challenge. A wide variety of treatments are available but most procedures offer suboptimal clinical effect and/or delayed therapeutic outcome. Only few therapeutic options have proven efficacy in the treatment of cellulite. To determine the efficacy and the safety profiles of radiofrequency and dynamic muscle activation technology in treatment of abdominal cellulite and circumference reduction. Twenty-five females with abdominal cellulite received 6 weekly radiofrequency and dynamic muscle activation treatments. Treatment areas included the abdomen and both sides of flanks. Subjects were evaluated using standardized photographs, and measurements of body weight and abdominal circumference at baseline, before every treatment visit, and 1 week and four weeks after the final treatment. Subcutaneous tissue thickness was recorded by ultrasound at baseline and 4 weeks after completion of treatment protocol. Physicians' evaluation and patient's satisfaction of clinical improvement were also measured. All subjects completed the treatment protocol and attended every follow-up visits. There was significant abdominal circumference reduction of 2.96 and 2.52 cm at 1-, and 4-week follow-up visits (p last treatment, the average circumferential reduction was sustained. Most of the patients were rated to have 25-49% improvement at 5th treatment, and 1- and 4-week follow-up visits. Ninety-two percent of the patients were satisfied with the treatment outcome. Radiofrequency provided beneficial effects on the reduction of abdomen and cellulite appearance. The benefit of muscle activation is yet to be determined.

Comparison of oral iodine-131-cellulose and indium-111-DTPA as tracers for colon transit scintigraphy: Analysis by colon activity profiles

International Nuclear Information System (INIS)

Smart, R.C.; McLean, R.G.; Gaston-Parry, D.; Barbagallo, S.; Bruck, C.E.; King, D.W.; Lubowski, D.Z.; Talley, N.A.

1991-01-01

In 11 normal subjects and 11 patients with a clinical diagnosis of constipation, oral 131I-cellulose and 111In-DTPA were compared simultaneously as tracers for radionuclide colon transit scintigraphy. Visual assessment of the images revealed no differences between tracers. Quantitation was performed using total and segmental percent retention and the derived value of clearance half-time. In addition, profiles of the activity distribution along the length of the colon were generated and the mean position of the activity in the colon calculated. For all indices, the results were similar in both normal subjects and constipated patients when comparing tracers, although marked differences were present between normal subjects and constipated patients for each tracer. Indium-111-DTPA was easy to administer and dosimetry was more acceptable than for 131I-cellulose, especially in constipated patients. It is concluded that 111In-DTPA is the preferred tracer for oral colon transit scintigraphy

Use of indium and rare-earths activable tracers for the evaluation of the hydraulic performance of wastewater treatment units

International Nuclear Information System (INIS)

Alvarenga, Gilmara Lucia Souza; Barreto, Alberto Avelar; Pinto, Amenonia Maria Ferreira; Moreira, Rubens Martins; Silva, Lauris Lucia da

2013-01-01

Efforts aimed at going deeper into the understanding of the purification processes of contaminated waters and at the optimization of both the technological and economic performance of such processes have been developed following the introduction of innovative wastewater treatment processes. Among the several wastewater depuration processes, this study focuses physical aspects of systems known as artificial wetlands and a special version of the anaerobic biological reactor. This biological reactor is of the upflow anaerobic sludge blanket (UASB) type, which is increasingly being utilized for the processing of urban wastewater. However, its effluent eventually needs some polishing to be performed at an artificial wetland stage. The hydrodynamic performances of both a special version of the UASB and a vegetated wetland have been studied using the tracer methodology, based on the impulse response of these systems. Both radioactive and activable tracers have been employed and had their information analyzed by appropriate software. Comments are presented on the advantages of the activable tracers. The results thus obtained have demonstrated the potential of the application of activable tracers in the experimental research of either natural or artificial hydraulic systems. (author)

Use of indium and rare-earths activable tracers for the evaluation of the hydraulic performance of wastewater treatment units

Energy Technology Data Exchange (ETDEWEB)

Alvarenga, Gilmara Lucia Souza; Barreto, Alberto Avelar; Pinto, Amenonia Maria Ferreira; Moreira, Rubens Martins, E-mail: gil_lsa@yahoo.com.br, E-mail: aab@cdtn.br, E-mail: amfp@cdtn.br, E-mail: rubens@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Silva, Lauris Lucia da, E-mail: laurislsilva@yahoo.com.br [Universidade Federal de Minas Gerais (DQ/UFMG), Minas Gerais, MG (Brazil). Dept. de Quimica

2013-07-01

Efforts aimed at going deeper into the understanding of the purification processes of contaminated waters and at the optimization of both the technological and economic performance of such processes have been developed following the introduction of innovative wastewater treatment processes. Among the several wastewater depuration processes, this study focuses physical aspects of systems known as artificial wetlands and a special version of the anaerobic biological reactor. This biological reactor is of the upflow anaerobic sludge blanket (UASB) type, which is increasingly being utilized for the processing of urban wastewater. However, its effluent eventually needs some polishing to be performed at an artificial wetland stage. The hydrodynamic performances of both a special version of the UASB and a vegetated wetland have been studied using the tracer methodology, based on the impulse response of these systems. Both radioactive and activable tracers have been employed and had their information analyzed by appropriate software. Comments are presented on the advantages of the activable tracers. The results thus obtained have demonstrated the potential of the application of activable tracers in the experimental research of either natural or artificial hydraulic systems. (author)

Predictive value of tracer studies for 131I treatment in hyperthyroid cats

International Nuclear Information System (INIS)

Broome, M.R.; Turrel, J.M.; Hays, M.T.

1988-01-01

In 76 cats with hyperthyroidism, peak thyroidal radioiodine ( 131 I) uptakes and effective half-lives were determined after administration of tracer and therapeutic activities of 131 I. In 6 additional hyperthyroid cats, only peak thyroidal uptakes after administration of tracer and therapeutic activities of 131 I were determined. Good correlation was found between peak thyroidal uptakes of tracer and therapeutic 131 I; however, only fair correlation was observed between effective half-lives. In 79% of the cats, the effective half-life for therapeutic 131 I was longer than that for tracer 131 I. After administration of therapeutic activity of 131 I, monoexponential and biphasic decay curves were observed in 51 and 16 cats, respectively. Using therapeutic kinetic data, radiation doses to the thyroid gland were calculated retrospectively on the basis of 2 methods for determining the activity of 131 I administered: (1) actual administration of tracer-compensated activity and (2) hypothetic administration of uniform activity (3 mCi). Because of the good predictive ability of tracer kinetic data for the therapeutic kinetic data, the tracer-compensated radiation doses came significantly (P = 0.008) closer to the therapeutic goal than did the uniform-activity doses. In addition, the use of tracer kinetic information reduced the extent of the tendency for consistently high uniform-activity doses. A manual method for acquiring tracer kinetic data was developed and was an acceptable alternative to computerized techniques. Adoption of this method gives individuals and institutions with limited finances the opportunity to characterize the iodine kinetics in cats before proceeding with administration of therapeutic activities of 131 I

Bromide as a tracer for studying water movement and nitrate displacement in soils: comparison with stable isotope tracers

International Nuclear Information System (INIS)

Russow, R.; Knappe, S.

1999-01-01

Tracers are an ideal means of studying water movement and associated nitrate displacement. Often bromide is preferred as a tracer because it is considered a representative tracer for water and because, being a conservative tracer (i.e. not involved in chemical and biological soil processes), it can be used for studying anion transport in soils. Moreover, it is less expensive and easier to measure than the stable isotopes deuterium and 15 N. Its great advantage over radioactive tracers (e.g. tritium), which outweighs their extreme sensitivity and ease of measurement and which it has in common with stable isotopes, is that it does not require radiation protection measures. However, there are also constraints on the use of bromide as a tracer in soil/water/plant systems. Our own studies on different soils using D 2 O, bromide and [ 15 N]-nitrate in lysimeters suggest that the above assumptions on bromide tracers need not always be valid under conditions as they prevail in biologically active soils. As the present paper shows, these studies permit a good assessment of the possibilities and limits to these tracers [de

Study on bioavailability of zinc for children's diet by using activable isotopic tracer 70Zn and neutron activation analysis techniques

International Nuclear Information System (INIS)

Zhang Yangmei; Ni Bangfa; Wang Pingsheng; Tian Weizhi; Cao Lei

2001-01-01

Bioavailability of zinc for three groups (low amount of diet zinc, balance amount of diet zinc and high amount of diet zinc) of children's diet is studied by using activable isotopic tracer 70 Zn and neutron activation analysis techniques. The results indicate that the fractional absorption of zinc from balance diet zinc group is the highest, up to 33.9%. A procedure of pre-irradiation concentration zinc for fecal samples using anion exchanger is developed, and the enriched 70 Zn with isotopic abundance of 18.3% is used for tracer. The mass ratios between 70 Zn and 68 Zn or 64 Zn and their contents between natural zinc and enriched zinc are used to calculate the bioavailability of zinc. Instrumental neutron activation analysis of 64 Zn of each original fecal samples and pre-irradiation concentrated zinc samples are used to normalize the chemical yield in order to reduce the uncertainty during the chemical separation procedure

Interaction of 1-iodochlordecone, as radioactive tracer, with the carboxylate group on activated carbon

International Nuclear Information System (INIS)

Gamboa-Carballo, Juan José; Melchor-Rodríguez, Kenia; Hernández-Valdés, Daniel; Jáuregui-Haza, Ulises Javier

2016-01-01

Chlordecone is a synthetic organo chlorinated compound that has been used as pesticide. It has been identified and listed as persistent organic pollutant by the Stockholm Convention. The use of activated carbon filters is one of the most widely popular solutions for water decontamination. The chlordecone labeled with radioactive iodine (1-iodochordecone) is a potential radioactive tracer for studying adsorption, environmental availability and bio-distribution of chlordecone. The selection of the best suited activation carbon for this type of contaminants is mainly an empiric process, increasing the costs of research. A simplified activation carbon model, consisting of a seven ring graphene sheet with a functional group (carboxylate) was used to assess the interaction of chlordecone and 1-iodochlordecone with this surface group under neutral pH conditions over the adsorption process. The Multiple Minima Hypersurface methodology with the semiempirical Hamiltonian PM7 was used. The results indicate that for carboxylate, in neutral conditions, significant associations appear which suggest chemisorption in activated carbon. No significant differences were observed for the interactions of chlordecone and 1 iodochlordecone with carboxylate, making 1-iodochlordecone a good candidate as a radioactive tracer in medical research. (author)

Tracer gas diffusion sampling test plan

International Nuclear Information System (INIS)

Rohay, V.J.

1993-01-01

Efforts are under way to employ active and passive vapor extraction to remove carbon tetrachloride from the soil in the 200 West Area an the Hanford Site as part of the 200 West Area Carbon Tetrachloride Expedited Response Action. In the active approach, a vacuum is applied to a well, which causes soil gas surrounding the well to be drawn up to the surface. The contaminated air is cleaned by passage through a granular activated carbon bed. There are questions concerning the radius of influence associated with application of the vacuum system and related uncertainties about the soil-gas diffusion rates with and without the vacuum system present. To address these questions, a series of tracer gas diffusion sampling tests is proposed in which an inert, nontoxic tracer gas, sulfur hexafluoride (SF 6 ), will be injected into a well, and the rates of SF 6 diffusion through the surrounding soil horizon will be measured by sampling in nearby wells. Tracer gas tests will be conducted at sites very near the active vacuum extraction system and also at sites beyond the radius of influence of the active vacuum system. In the passive vapor extraction approach, barometric pressure fluctuations cause soil gas to be drawn to the surface through the well. At the passive sites, the effects of barometric ''pumping'' due to changes in atmospheric pressure will be investigated. Application of tracer gas testing to both the active and passive vapor extraction methods is described in the wellfield enhancement work plan (Rohay and Cameron 1993)

Tracer-tracer relations as a tool for research on polar ozone loss

Energy Technology Data Exchange (ETDEWEB)

Mueller, Rolf

2010-07-01

The report includes the following chapters: (1) Introduction: ozone in the atmosphere, anthropogenic influence on the ozone layer, polar stratospheric ozone loss; (2) Tracer-tracer relations in the stratosphere: tracer-tracer relations as a tool in atmospheric research; impact of cosmic-ray-induced heterogeneous chemistry on polar ozone; (3) quantifying polar ozone loss from ozone-tracer relations: principles of tracer-tracer correlation techniques; reference ozone-tracer relations in the early polar vortex; impact of mixing on ozone-tracer relations in the polar vortex; impact of mesospheric intrusions on ozone-tracer relations in the stratospheric polar vortex calculation of chemical ozone loss in the arctic in March 2003 based on ILAS-II measurements; (4) epilogue.

Radioactive tracers in the sea

International Nuclear Information System (INIS)

Jenkins, W.J.; Livingston, H.D.

1980-01-01

Artificial radionuclides introduced to the oceans during the last four decades have proved invaluable tools for study of many processes in marine water columns and sediments. Both global and close-in fallout of radioactivity from atmospheric nuclear weapons testing have distributed these radionuclides widely, and in amounts sufficient to be useful as tracers. An additional source of considerable significance and tracer potential comes from coastal discharges of European nuclear fuel reprocessing wastes. The nature of these sources, types and amounts of radionuclides introduced and the time histories of their introduction generate a variety of tracer distributions which illuminate a broad spectrum of physical and chemical processes active over a wide range of timescales. Depending on their respective chemistries, artificial radionuclides have been demonstrated to exhibit both conservative and non-conservative properties in the oceans. Some examples are given of the uses made of soluble, conservative tracers for the study of oceanic transport processes and of non-conservative tracers for studies of processes which move them to, and mix them within, marine sediments. Sampling and measurement techniques which have been used in these studies are described

Systematic screening of imaging biomarkers for the Islets of Langerhans, among clinically available positron emission tomography tracers

International Nuclear Information System (INIS)

Karlsson, Filip; Antonodimitrakis, Pantelis Clewemar; Eriksson, Olof

2015-01-01

Introduction: Functional imaging could be utilized for visualizing pancreatic islets of Langerhans. Therefore, we present a stepwise algorithm for screening of clinically available positron emission tomography (PET) tracers for their use in imaging of the neuroendocrine pancreas in the context of diabetes. Methods: A stepwise procedure was developed for screening potential islet imaging agents. Suitable PET-tracer candidates were identified by their molecular mechanism of targeting. Clinical abdominal examinations were retrospectively analyzed for pancreatic uptake and retention. The target protein localization in the pancreas was assessed in silico by –omics approaches and the in vitro by binding assays to human pancreatic tissue. Results: Six putative candidates were identified and screened by using the stepwise procedure. Among the tested PET tracers, only [ 11 C]5-Hydroxy-tryptophan passed all steps. The remaining identified candidates were falsified as candidates and discarded following in silico and in vitro screening. Conclusions: Of the six clinically available PET tracers identified, [ 11 C]5-HTP was found to be a promising candidate for beta cell imaging, based on intensity of in vivo pancreatic uptake in humans, and islet specificity as assessed on human pancreatic cell preparations. The flow scheme described herein constitutes a methodology for evaluating putative islet imaging biomarkers among clinically available PET tracers

Field measurement of mixing degree in coal mixer by later activable tracer method

International Nuclear Information System (INIS)

Yokooji, Makoto; Uemura, Katsumi; Adachi, Syoichi

1975-01-01

Mixing effectiveness in a rotary drum mixer for coke production was examined. Though the method to use the dispersion of characteristic values such as ash content or volatile components is common for measuring the mixing effectiveness, here the later activable tracer method with radioisotopes was employed, because the former method includes the dispersion of the characteristic values for raw materials themselves, and is poor in detectability. In a preliminary test, the expression for mixing degree was determined, and the tracer nuclide was selected. Coal mixture was irradiated in the TRIGA II reactor of St. Paul University for 4 hours at 100 kW. then further preliminary test was performed for La and Mn which were selected among the typical usable elements listed up by reviewing their γ-spectra. Finally, Mn was adopted by comparing both elements regarding their time required for activation analysis and economy. Manganese concentration originally contained in the coal mixture was 38 ppm. Mixing degree after passing through the coal mixer was 99.8%. The results of the regular test are shown in a table, and indicate that the mixer fully attained its aim. (Wakatsuki, Y.)

Tracer theory

International Nuclear Information System (INIS)

Margrita, R.

1988-09-01

Tracers are used in many fields of science to investigate mass transfer. The scope of tracers applications in Service of Applications Radioisotopes (S.A.R.-France) is large and concerns natural and industrial systems such as Sciences of earth: hydrology - civil engineering - Sedimentology - environmental studies. Industrial field: chemical engineering - mechanical engineering. A general tracer methodology has been developed in our laboratories from these different applications fields and this paper shows these different points of view in using tracers; our wish is that the methods used in an experimental field can be employed in an another one

Associations of objectively measured physical activity and abdominal fat distribution

DEFF Research Database (Denmark)

Philipsen, Annelotte; Hansen, Anne-Louise Smidt; Jørgensen, Marit Eika

2015-01-01

Introduction/Purpose: Visceral adipose tissue (VAT) and physical activity are both independent predictors of Type 2 diabetes. Physical activity and overall obesity are inversely associated with each other. Yet the nature of the association between objectively measured dimensions of physical...... activity and abdominal fat distribution has not been well characterized. We aimed to do so in a middle-age to elderly population at high risk of diabetes. Methods: A cross-sectional analysis of 1134 participants of the ADDITION-PRO study. VAT and subcutaneous adipose tissue (SAT) were assessed one......-dimensionally by ultrasonography and physical activity with combined accelerometry and HR monitoring. Linear regression of physical activity energy expenditure (PAEE) and time spent in different physical activity intensity levels on VAT and SAT was performed. Results: Median body mass index (BMI) was 26.6 kg.m(-2) and PAEE was 28...

Significance of residual abdominal masses in children with abdominal Burkitt's lymphoma

International Nuclear Information System (INIS)

Karmazyn, B.; Horev, G.; Kornreich, L.; Ash, S.; Goshen, Y.; Yaniv, I.

2001-01-01

Purpose: To evaluate the natural history of children with abdominal Burkitt's lymphoma who had complete clinical remission and residual abdominal mass after treatment. Material and methods: The charts and imaging findings of all children with abdominal Burkitt's lymphoma treated and followed at our medical center between 1988 and 1999 were reviewed for the presence, management, clinical course, and prognosis of residual mass. Results: Only children who achieved complete clinical remission were included. The study group consisted of 33 children (20 boys and 13 girls) aged 2.6-17.6 years (mean 7.2 years). Of these, seven (20.6 %) were found to have a residual abdominal mass. Two underwent second-look operation with no evidence of viable tumor on histology. The remaining five were followed by imaging studies for 2.2-9.1 years (mean 6.1 years); none relapsed. Conclusion: Residual mass is not uncommon in children with abdominal Burkitt's lymphoma. The presence of residual mass in a child with complete clinical remission does not alter the long-term prognosis. Therefore, in children with Burkitt's lymphoma and residual mass with no other signs of disease activity, expectant watching may be appropriate. (orig.)

A comparative analysis of the electrical activity of the abdominal muscles during traditional and Pilates-based exercises under two conditions

Directory of Open Access Journals (Sweden)

Mariana Felipe Silva

2013-04-01

Full Text Available The use of Pilates-based exercises for trunk strengthening has been reported in the literature. The objective of this study was to analyze and compare the electrical activity of the rectus abdominis and external oblique muscles during a traditional abdominal exercise program and an exercise program based on the Pilates method using a ball and an elastic band. The sample was composed of 10 healthy women, non-practitioners of Pilates, who performed the traditional abdominal exercise and roll-up with the ball and elastic band. The sign was normalized by the electromyographic peak of the dynamics activity and was adjusted for 2000 samples/s; the filter was set in a frequency band from 20 to 450 Hz. In the comparison between exercises, the external oblique muscle in the concentric phase had a higher recruitment in the roll-up with the ball (P =0.042. In the comparison between muscles in each exercise, the rectus abdominis showed a higher activation in the concentric phase (P = 0.009 and in the eccentric phase (P = 0.05 of the traditional abdominal exercise. Activation percentages ranged from 15% to 22%. The traditional abdominal exercise had the largest activation percentage.

Tracer techniques in food industry

International Nuclear Information System (INIS)

Pertsovskij, E.S.; Sakharov, Eh.V.; Dolinin, V.A.

1980-01-01

The appicability of radioactive tracer techniques to process control in food industry are considered. Investigations in the field of food industry carried out using the above method are classified. The 1 class included investigations with preliminary preparation of a radioactive indicator and its following introduction in the system studied. The 2 class includes investigations based on the introduction in the system studied of a non-active indicator which is activated in a neutron flux being in samples selected in or after the process investigated. The 3 class includes studies based on investigations of natural radioactivity of certain nuclides in food stuff. The application of tracer techniques to the above classes of investigations in various fields of food industry and the equipment applied are considered in detail [ru

Active tracer analysis of iron in anemia children's diet

International Nuclear Information System (INIS)

Zhang Yunhui; Xiao Lun

1994-01-01

With stable 58 Fe as tracer the absorption rate of iron in anemia children's diet is determined by INAA. Children are four to five years old. FeCl 2 solution of enriched 58 Fe is taken orally. The feces five days ever since are collected, dried and irradiated in the reactor and activity of 59 Fe is measured. This method is accurate, reliable, applicable and harmless. It may be applied to determine Zn, Ca and other elements. The experimental results show that: (1) Soybean protein makes no contribution to, or may even inhibit, the absorption of iron from the diet. (2) With vitamin C added to soybean protein, the absorption rate of iron is increased. (3) Specifically treated soybean sprouts powder or fermented soybean powder enhances the biological utilization of iron

Relationships between activators and inhibitors of plasminogen, and the progression of small abdominal aortic aneurysms

DEFF Research Database (Denmark)

Lindholt, Jes Sanddal; Jørgensen, B; Shi, G-P

2003-01-01

plasmin is a common activator of the known proteolytic systems involved in the aneurysmal degradation, and is reported to be associated with the expansion of abdominal aortic aneurysms (AAA). The aim of this study was to study the activating pathways of plasminogen as predictors of the progression...

Tuberculosis abdominal Abdominal tuberculosis

OpenAIRE

T. Rubio; M. T. Gaztelu; A. Calvo; M. Repiso; H. Sarasíbar; F. Jiménez Bermejo; A. Martínez Echeverría

2005-01-01

La tuberculosis abdominal cursa con un cuadro inespecífico, con difícil diagnóstico diferencial respecto a otras entidades de similar semiología. Presentamos el caso de un varón que ingresa por presentar dolor abdominal, pérdida progresiva y notoria de peso corporal y fiebre de dos meses de evolución. El cultivo de la biopsia de colon mostró presencia de bacilo de Koch.Abdominal tuberculosis develops according to a non-specific clinical picture, with a difficult differential diagnosis with re...

Randomized trial of amino acid mixture combined with physical activity promotion for abdominal fat reduction in overweight adults.

Science.gov (United States)

Ueda, Keisuke; Sasai, Hiroyuki; Tsujimoto, Takehiko; Sanbongi, Chiaki; Ikegami, Shuji; Kobayashi, Hiroyuki; Shioya, Nobuhiko; Suzuki, Satoru; Nakata, Yoshio

2018-01-01

The purpose of this study was to test the efficacy of arginine, alanine, and phenylalanine mixture (A-mix) ingestion at 1,500 mg/day in combination with the promotion of physical activity for abdominal fat reduction in overweight adults. A placebo-controlled, double-blind, parallel-group, randomized trial for 12 weeks combined with a 4-week follow-up period was conducted at a single center in Minato-ku, Tokyo, Japan, between December 2016 and May 2017. Data were analyzed between June and August 2017. The study participants were 200 overweight adults within the age range of 20-64 years. The participants were randomly assigned to the A-mix group (n=100) or a placebo group (n=100) and were administered 500 mL of test beverage containing 1,500 or 0 mg of A-mix, respectively, for 12 weeks. All participants maintained a physically active lifestyle between week 0 and week 12 through monthly sessions of physical activity. The primary outcomes were the 12-week changes in the abdominal total, subcutaneous, and visceral fat areas, as assessed by computed tomography. Of the 200 enrolled participants, 199 (99%) accomplished the 12-week intervention and 4-week follow-up period. The per-protocol-based analysis for 194 participants demonstrated that the abdominal total fat area decreased significantly in the A-mix group compared with that in the placebo group (difference, 10.0 cm 2 ; 95% confidence interval [CI]: 0.4-19.6 cm 2 ; P =0.041). Comparable outcomes were obtained for the abdominal subcutaneous fat area (difference, 7.4 cm 2 ; 95% CI: 0.1-14.7 cm 2 ; P =0.047). No study-related unfavorable events occurred. A-mix supplementation in combination with physical activity promotion facilitated abdominal fat reduction in overweight adults.

Active thermal tracer testing in a shallow aquifer of the Thur valley, Switzerland

Science.gov (United States)

Schweingruber, Mischa; Somogyvári, Márk; Bayer, Peter

2015-04-01

Tracer tests are one of the standard methods for investigating groundwater processes. Among the range of different test variants, using heat as a tracer has gained substantial interest during the last decade. Temperature measurements have become essential ingredients for example for characterization of river-aquifer interactions and in the field of geothermics. Much less attention than on natural temperature signals has been devoted to induced synthetic temperature signals, even though it is well known that temperature is an easy to measure, invisible but sensitive system property. Design, application and inversion of such active thermal tracer tests represent one focus of our work. We build up on the experience from related field experiments, where heated water was injected and the propagation of the generated thermal anomaly was monitored. In this presentation, we show the results from first field-testing in an alluvial aquifer at the Widen site in the Thur valley in Switzerland. The thermal evolution of groundwater was monitored in summer 2014 during and after several days of heated water injection. By this test, we want to derive insights into the prevailing hydraulic heterogeneity of the shallow aquifer at the site. The results are used for calibration of a two dimensional hydrogeological numerical model. With the calibrated hydraulic conductivity field, the experiment is simulated and the transient evolution of the heat plume is visualized. Hydraulic heterogeneity is identified as one main factor for lateral spreading of the heat plume. The most important result of the experiment is that the significance of the ambient flow field is very high and even with high pumping rates to establish forced gradient conditions its effect cannot be overridden. During the test, precious technical experience was gained, which will be beneficial for subsequent heat tracer applications. For example, the challenge of maintaining a constant injection rate and temperature could

Synthesis of tracers using automated radiochemistry and robotics

International Nuclear Information System (INIS)

Dannals, R.F.

1992-07-01

Synthesis of high specific activity radiotracers labeled with short-lived positron-emitting radionuclides for positron emission tomography (PET) often requires handling large initial quantities of radioactivity. High specific activities are required when preparing tracers for use in PET studies of neuroreceptors. A fully automated approach for tracer synthesis is highly desirable. This proposal involves the development of a system for the Synthesis of Tracers using Automated Radiochemistry and Robotics (STARR) for this purpose. While the long range objective of the proposed research is the development of a totally automated radiochemistry system for the production of major high specific activity 11 C-radiotracers for use in PET, the specific short range objectives are the automation of 11 C-methyl iodide ( 11 CH 3 I) production via an integrated approach using both radiochemistry modular labstations and robotics, and the extension of this automated capability to the production of several radiotracers for PET (initially, 11 C-methionine, 3-N-[ 11 C-methyl]spiperone, and [ 11 C]-carfentanil)

Staged abdominal re-operation for abdominal trauma.

Science.gov (United States)

Taviloglu, Korhan

2003-07-01

To review the current developments in staged abdominal re-operation for abdominal trauma. To overview the steps of damage control laparotomy. The ever increasing importance of the resuscitation phase with current intensive care unit (ICU) support techniques should be emphasized. General surgeons should be familiar to staged abdominal re-operation for abdominal trauma and collaborate with ICU teams, interventional radiologists and several other specialties to overcome this entity.

Activity of Lower Limb Muscles During Squat With and Without Abdominal Drawing-in and Pilates Breathing.

Science.gov (United States)

Barbosa, Alexandre C; Martins, Fábio M; Silva, Angélica F; Coelho, Ana C; Intelangelo, Leonardo; Vieira, Edgar R

2017-11-01

Barbosa, AC, Martins, FM, Silva, AF, Coelho, AC, Intelangelo, L, and Vieira, ER. Activity of lower limb muscles during squat with and without abdominal drawing-in and Pilates breathing. J Strength Cond Res 31(11): 3018-3023, 2017-The purpose of this study was to assess the effects of abdominal drawing-in and Pilates breathing on the activity of lower limb muscles during squats. Adults (n = 13, 22 ± 3 years old) with some Pilates experience performed three 60° squats under each of the following conditions in a random order: (I) normal breathing, (II) drawing-in maneuver with normal breathing, and (III) drawing-in maneuver with Pilates breathing. Peak-normalized surface electromyography of the rectus femoris, biceps femoris, gastrocnemius medialis, and tibialis anterior during the knee flexion and extension phases of squat exercises was analyzed. There were significant differences among the conditions during the knee flexion phase for the rectus femoris (p = 0.001), biceps femoris (p = 0.038), and tibialis anterior (p = 0.001), with increasing activation from conditions I to III. For the gastrocnemius medialis, there were significant differences among the conditions during the knee extension phase (p = 0.023), with increased activity under condition I. The rectus and biceps femoris activity was higher during the extension vs. flexion phase under conditions I and II. The tibialis anterior activity was higher during the flexion compared with the extension phase under all conditions, and the medial gastrocnemius activity was higher during the extension phase under condition I. Doing squats with abdominal drawing-in and Pilates breathing resulted in increased rectus, biceps femoris, and tibialis anterior activity during the flexion phase, increasing movement stability during squat exercises.

Kinetic and Related Determinants of Plasma Triglyceride Concentration in Abdominal Obesity: Multicenter Tracer Kinetic Study.

Science.gov (United States)

Borén, Jan; Watts, Gerald F; Adiels, Martin; Söderlund, Sanni; Chan, Dick C; Hakkarainen, Antti; Lundbom, Nina; Matikainen, Niina; Kahri, Juhani; Vergès, Bruno; Barrett, P Hugh R; Taskinen, Marja-Riitta

2015-10-01

Patients with obesity and diabetes mellitus have increased risk of cardiovascular disease. A major cause is an atherogenic dyslipidemia related primarily to elevated plasma concentrations of triglyceride-rich lipoproteins. The aim of this study was to clarify determinants of plasma triglyceride concentration. We focused on factors that predict the kinetics of very-low density lipoprotein 1 (VLDL1) triglycerides. A multicenter study using dual stable isotopes (deuterated leucine and glycerol) and multicompartmental modeling was performed to elucidate the kinetics of triglycerides and apoB in VLDL1 in 46 subjects with abdominal obesity and additional cardiometabolic risk factors. Results showed that plasma triglyceride concentrations were dependent on both the secretion rate (r=0.44, Ptriglycerides and VLDL1-apoB. Liver fat mass was independently and directly associated with secretion rates of VLDL1-triglycerides (r=0.56, Ptriglycerides (r=0.48, Ptriglyceride concentrations in abdominal obesity are determined by the kinetics of VLDL1 subspecies, catabolism being mainly dependent on apoC-III concentration and secretion on liver fat content. Reduction in liver fat and targeting apoC-III may be an effective approach for correcting triglyceride metabolism atherogenic dyslipidemia in obesity. © 2015 American Heart Association, Inc.

Abdominal Tuberculosis Mimicking Intra-abdominal Malignancy: A ...

African Journals Online (AJOL)

TNHJOURNALPH

BACKGROUND. Abdominal TB usually presents with nonspecific findings and may thus m.,mw a multitude of gastrointestinal disorders. Abdominal tuberculosis may therefore present as large and palpable intra-abdominal masses usually arising from lymphadenopathy which may mimic lymphomas and other malignancies.

Abdominal tuberculosis mimicking intra-abdominal malignancy: A ...

African Journals Online (AJOL)

Background: Abdominal TB usually presents with nonspecific findings and may thus mimic a multitude of gastrointestinal disorders. Abdominal tuberculosis may therefore present as large and palpable intra-abdominal masses usually arising from lymphadenopathy which may mimic lymphomas and other malignancies.

[{sup 11}C]FMAU and [{sup 18}F]FHPG as PET tracers for herpes simplex virus thymidine kinase enzyme activity and human cytomegalovirus infections

Energy Technology Data Exchange (ETDEWEB)

Vries, Erik F.J. de E-mail: e.f.j.de.vries@pet.azg.nl; Waarde, Aren van; Harmsen, Marco C.; Mulder, Nanno H.; Vaalburg, Willem; Hospers, Geke A.P

2000-02-01

[{sup 11}C]-2'-Fluoro-5-methyl-1-{beta}-D-arabinofuranosyluracil ([{sup 11}C]FMAU) and [{sup 18}F]-9-[(3-fluoro-1-hydroxy-2-propoxy)methyl]guanine ([{sup 18}F]FHPG), radiolabeled representatives of two classes of antiviral agents, were evaluated as tracers for measuring herpes simplex virus thymidine kinase (HSV-tk) enzyme activity after gene transfer and as tracers for localization of active human cytomegalovirus (HCMV) infections. In vitro accumulation experiments revealed that both [{sup 11}C]FMAU and [{sup 18}F]FHPG accumulated significantly more in HSV-tk expressing cells than they did in control cells. [{sup 18}F]FHPG uptake in HSV-tk expressing cells, however, was found to depend strongly on the cell line used, which might be due to cell type dependent membrane transport or cell type dependent substrate specific susceptibility of the enzyme. In vitro, both tracers exhibited a good selectivity for accumulation in HCMV-infected human umbilical vein endothelial cells over uninfected cells. In contrast to [{sup 18}F]FHPG, [{sup 11}C]FMAU uptake in control cells was relatively high due to phosphorylation of the tracer by host kinases. Therefore, [{sup 18}F]FHPG appears to be the more selective tracer not only to predict HSV-tk gene therapy outcome, but also to localize active HCMV infections with PET.

Nontraumatic abdominal emergencies: acute abdominal pain: diagnostic strategies

International Nuclear Information System (INIS)

Marincek, B.

2002-01-01

Common causes of acute abdominal pain include appendicitis, cholecystitis, bowel obstruction, urinary colic, perforated peptic ulcer, pancreatitis, diverticulitis, and nonspecific, nonsurgical abdominal pain. The topographic classification of acute abdominal pain (pain in one of the four abdominal quadrants, diffuse abdominal pain, flank or epigastric pain) facilitates the choice of the imaging technique. The initial radiological evaluation often consists of plain abdominal radiography, despite significant diagnostic limitations. The traditional indications for plain films - bowel obstruction, pneumoperitoneum, and the search of ureteral calculi - are questioned by helical computed tomography (CT). Although ultrasonography (US) is in many centers the modality of choice for imaging the gallbladder and the pelvis in children and women of reproductive age, CT is considered to be one of the most valued tools for triaging patients with acute abdominal pain. CT is particularly beneficial in patients with marked obesity, unclear US findings, bowel obstruction, and multiple lesions. The introduction of multidetector row CT (MDCT) has further enhanced the utility of CT in imaging patients with acute abdominal pain. (orig.)

Nontraumatic abdominal emergencies: acute abdominal pain: diagnostic strategies

Energy Technology Data Exchange (ETDEWEB)

Marincek, B. [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland)

2002-09-01

Common causes of acute abdominal pain include appendicitis, cholecystitis, bowel obstruction, urinary colic, perforated peptic ulcer, pancreatitis, diverticulitis, and nonspecific, nonsurgical abdominal pain. The topographic classification of acute abdominal pain (pain in one of the four abdominal quadrants, diffuse abdominal pain, flank or epigastric pain) facilitates the choice of the imaging technique. The initial radiological evaluation often consists of plain abdominal radiography, despite significant diagnostic limitations. The traditional indications for plain films - bowel obstruction, pneumoperitoneum, and the search of ureteral calculi - are questioned by helical computed tomography (CT). Although ultrasonography (US) is in many centers the modality of choice for imaging the gallbladder and the pelvis in children and women of reproductive age, CT is considered to be one of the most valued tools for triaging patients with acute abdominal pain. CT is particularly beneficial in patients with marked obesity, unclear US findings, bowel obstruction, and multiple lesions. The introduction of multidetector row CT (MDCT) has further enhanced the utility of CT in imaging patients with acute abdominal pain. (orig.)

Environmental Tracers

Directory of Open Access Journals (Sweden)

Trevor Elliot

2014-10-01

Full Text Available Environmental tracers continue to provide an important tool for understanding the source, flow and mixing dynamics of water resource systems through their imprint on the system or their sensitivity to alteration within it. However, 60 years or so after the first isotopic tracer studies were applied to hydrology, the use of isotopes and other environmental tracers are still not routinely necessarily applied in hydrogeological and water resources investigations where appropriate. There is therefore a continuing need to promote their use for developing sustainable management policies for the protection of water resources and the aquatic environment. This Special Issue focuses on the robustness or fitness-for-purpose of the application and use of environmental tracers in addressing problems and opportunities scientifically, to promote their wider use and to address substantive issues of vulnerability, sustainability, and uncertainty in (groundwater resources systems and their management.

Obesidade abdominal em adolescentes: prevalência e associação com atividade física e hábitos alimentares Abdominal obesity in adolescents: prevalence and association with physical activity and eating habits

Directory of Open Access Journals (Sweden)

Cláudio Barnabé dos Santos Cavalcanti

2010-03-01

cardiovascular and metabolic diseases, but its prevalence and the factors associated with its occurrence are unknown. OBJECTIVES: To determine the prevalence of abdominal obesity in adolescents, and to evaluate whether the indicators of physical activity and dietary habits are associated with the occurrence of abdominal obesity in adolescents. METHODS: The sample included 4138 high school students (14-19 years, selected by cluster sampling in two stages. We obtained data using the Global School-based Health Survey, and anthropometric measurements were taken for determination of overweight and abdominal obesity. Logistic regression was used for analysis of behavioral factors associated with the occurrence of abdominal obesity. The identification of cases of abdominal obesity was performed by waist circumference analysis, using age- and gender-related cutoff points as reference. RESULTS: The mean age was 16.8 years (s = 1.4, and 59.8% of subjects were female. The prevalence of abdominal obesity was 6% (95%CI: 5.3-6.7, and it was significantly higher among girls (6.7%, 95%CI: 5.8-7.8 than among boys (4.9%, 95%CI: 3, 9-6, 0. In the crude analysis, gender and overweight were associated with the occurrence of abdominal obesity. The analysis adjustment by logisic regression allowed us to observe that physical activity was significantly associated with the occurrence of obesity in this group (OR = 0.7; 95% CI: 0.49-0.99, regardless of the presence of overweight. CONCLUSIONS: The prevalence of abdominal obesity was low compared to that observed in international studies, and physical activity was a factor associated with the occurrence of this event in adolescents.

Enhancing the activation of silicon carbide tracer particles for PEPT applications using gas-phase deposition of alumina at room temperature and atmospheric pressure

Energy Technology Data Exchange (ETDEWEB)

Valdesueiro, D. [Delft University of Technology, Department of Chemical Engineering, 2628 BL Delft (Netherlands); Garcia-Triñanes, P., E-mail: p.garcia@surrey.ac.uk [Department of Chemical and Process Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Meesters, G.M.H.; Kreutzer, M.T. [Delft University of Technology, Department of Chemical Engineering, 2628 BL Delft (Netherlands); Gargiuli, J.; Leadbeater, T.W.; Parker, D.J. [Positron Imaging Centre, School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Seville, J.P.K. [Department of Chemical and Process Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Ommen, J.R. van, E-mail: j.r.vanommen@tudelft.nl [Delft University of Technology, Department of Chemical Engineering, 2628 BL Delft (Netherlands)

2016-01-21

We have enhanced the radio-activation efficiency of SiC (silicon carbide) particles, which by nature have a poor affinity towards {sup 18}F ions, to be employed as tracers in studies using PEPT (Positron Emission Particle Tracking). The resulting SiC–Al{sub 2}O{sub 3} core–shell structure shows a good labelling efficiency, comparable to γ-Al{sub 2}O{sub 3} tracer particles, which are commonly used in PEPT. The coating of the SiC particles was carried at 27±3 °C and 1 bar in a fluidized bed reactor, using trimethylaluminium and water as precursors, by a gas phase technique similar to atomic layer deposition. The thickness of the alumina films, which ranged from 5 to 500 nm, was measured by elemental analysis and confirmed with FIB-TEM (focused ion beam – transmission electron microscope), obtaining consistent results from both techniques. By depositing such a thin film of alumina, properties that influence the hydrodynamic behaviour of the SiC particles, such as size, shape and density, are hardly altered, ensuring that the tracer particle shows the same flow behaviour as the other particles. The paper describes a general method to improve the activation efficiency of materials, which can be applied for the production of tracer particles for many other applications too. - Highlights: • We deposited Al{sub 2}O{sub 3} films on SiC particles at ambient conditions in a fluidized bed. • The affinity of {sup 18}F ions towards Al{sub 2}O{sub 3}–SiC particle was improved compared to SiC. • We used the Al{sub 2}O{sub 3}–SiC activated particle as tracer in a PEPT experiment. • Tracer particles have suitable activity for accurate tracking. • The Al{sub 2}O{sub 3} film is thin enough not to alter the particle size, shape and density.

Bromide as a tracer for studying water movement and nitrate displacement in soils: comparison with stable isotope tracers; Bromid als Tracer zur Untersuchung der Wasserbewegung und der Nitratverlagerung in Boeden: Vergleich mit stabilisotopen Tracern

Energy Technology Data Exchange (ETDEWEB)

Russow, R.; Knappe, S. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Bad Lauchstaedt (Germany). Sektion Bodenforschung

1999-02-01

Tracers are an ideal means of studying water movement and associated nitrate displacement. Often bromide is preferred as a tracer because it is considered a representative tracer for water and because, being a conservative tracer (i.e. not involved in chemical and biological soil processes), it can be used for studying anion transport in soils. Moreover, it is less expensive and easier to measure than the stable isotopes deuterium and {sup 15}N. Its great advantage over radioactive tracers (e.g. tritium), which outweighs their extreme sensitivity and ease of measurement and which it has in common with stable isotopes, is that it does not require radiation protection measures. However, there are also constraints on the use of bromide as a tracer in soil/water/plant systems. Our own studies on different soils using D{sub 2}O, bromide and [{sup 15}N]-nitrate in lysimeters suggest that the above assumptions on bromide tracers need not always be valid under conditions as they prevail in biologically active soils. As the present paper shows, these studies permit a good assessment of the possibilities and limits to these tracers. [Deutsch] Fuer die Untersuchung der Wasserbewegung sowie der daran gekoppelten Nitrat-Verlagerung ist der Einsatz von Tracern das Mittel der Wahl. Dabei wird Bromid als Tracer haeufig bevorzugt, da es allgemein als ein repraesentativer Tracer fuer Wasser und als konservativer Tracer (nicht involviert in chemische und biologische Bodenprozesse) zur Untersuchung des Anionentransportes in Boeden angesehen wird und es gegenueber den stabilen Isotopen Deuterium und {sup 15}N billiger und einfacher zu bestimmen ist. Gegenueber den radioaktiven Tracern (z.B. Tritium), die zwar sehr empfindlich und einfach messbar sind, besteht der grosse Vorteil, dass, wie bei den stabilen Isotopen, keine Strahlenschutzmassnahmen ergriffen werden muessen. Es gibt jedoch auch einschraenkende Hinweise fuer die Verwendung von Bromid als Tracer im System Boden

Suitable activated carbon-13 tracer techniques

International Nuclear Information System (INIS)

Zhang Weicheng; Peng Xiuru; Wang Yuhua

1995-12-01

Feasibility and applicability studies of the proton induced gamma ray emission (PIGE) have been performed. The graphite was firstly bombarded at various proton energies to determine gamma ray yield (and, thus, sensitivities) for the reaction of interest. The accuracy for the determination of 13 C abundance was checked, and the precision with which this value and ratios 13 C/ 12 C may be obtained was established by repetitive analysis samples. The performance of different standards in this determination was assessed. The mathematical treatment was developed for the determination of 13 C abundance in tracer studies, and to derive the equations that govern this method of analysis from first principles, to arrive finally at a simple expression by virtue of the observed regularities. The system was calibrated by measuring the gamma ray yield form the 12 C (p, γ) 13 N and 13 C(p,γ) 14 N reaction as a function of known 13 C enrichment. Using this experimentally determined calibration curve, unknown materials can be assayed. This technique is applicable to the analysis of samples with 13 C enrichments between 0.1% and 90%. The samples of human breath natural samples were analyzed against graphite and Cylinder CO 2 standards. Relative standard deviations were 13 C abundance, an increase in 13 C per cent isotopic abundance from the natural 1.11% (average) to only 1.39% may be ascertained. Finally, PIGE is compared with more classical techniques for analysis of 13 C tracer experiments. Ease and speed are important advantages of this technique over mass spectrometry, and its error is compatible with the natural variation of biological results. (9 refs., 11 figs., 9 tabs.)

Study on adsorption of activated carbon fiber to background-level xenon in air by the method of 133Xe tracer

International Nuclear Information System (INIS)

Zhang Haitao; Wang Yalong; Zhang Lixing; Wang Xuhui; Zhang Xiaolin

2001-01-01

The adsorption behaviors of the different activated carbon fibers to ultra-trace xenon in air are studied using the method of 133 Xe as tracer. The efficiency equation of adsorption columns are determined. The comparison of adsorptive capacity between activated carbon fibers and activated carbon indicates that activated carbon fibers are better than activated carbon under low temperature

Intricate but tight coupling of spiracular activity and abdominal ventilation during locust discontinuous gas exchange cycles.

Science.gov (United States)

Talal, Stav; Gefen, Eran; Ayali, Amir

2018-03-15

Discontinuous gas exchange (DGE) is the best studied among insect gas exchange patterns. DGE cycles comprise three phases, which are defined by their spiracular state: closed, flutter and open. However, spiracle status has rarely been monitored directly; rather, it is often assumed based on CO 2 emission traces. In this study, we directly recorded electromyogram (EMG) signals from the closer muscle of the second thoracic spiracle and from abdominal ventilation muscles in a fully intact locust during DGE. Muscular activity was monitored simultaneously with CO 2 emission, under normoxia and under various experimental oxic conditions. Our findings indicate that locust DGE does not correspond well with the commonly described three-phase cycle. We describe unique DGE-related ventilation motor patterns, coupled to spiracular activity. During the open phase, when CO 2 emission rate is highest, the thoracic spiracles do not remain open; rather, they open and close rapidly. This fast spiracle activity coincides with in-phase abdominal ventilation, while alternating with the abdominal spiracle and thus facilitating a unidirectional air flow along the main trachea. A change in the frequency of rhythmic ventilation during the open phase suggests modulation by intra-tracheal CO 2 levels. A second, slow ventilatory movement pattern probably serves to facilitate gas diffusion during spiracle closure. Two flutter-like patterns are described in association with the different types of ventilatory activity. We offer a modified mechanistic model for DGE in actively ventilating insects, incorporating ventilatory behavior and changes in spiracle state. © 2018. Published by The Company of Biologists Ltd.

Mechanisms and management of functional abdominal pain

OpenAIRE

Farmer, Adam D; Aziz, Qasim

2014-01-01

Functional abdominal pain syndrome is characterised by frequent or continuous abdominal pain associated with a degree of loss of daily activity. It has a reported population prevalence of between 0.5% and 1.7%, with a female preponderance. The pathophysiology of functional abdominal pain is incompletely understood although it has been postulated that peripheral sensitisation of visceral afferents, central sensitisation of the spinal dorsal horn and aberrancies within descending modulatory sys...

Uptake and transport of positron-emitting tracer in plants

Energy Technology Data Exchange (ETDEWEB)

Kume, Tamikazu; Matsuhashi, Shinpei; Shimazu, Masamitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; and others

1997-03-01

The transport of a positron-emitting isotope introduced into a plant was dynamically followed by a special observation apparatus called `Positron-Emitting Tracer Imaging System`. In the system, annihilation {gamma}-rays from the positron emitter are detected with two planer detectors (5 x 6 cm square). The water containing ca. 5 MBq/ml of {sup 18}F was fed to the cut stem of soybean for 2 min and then the images of tracer activity were recorded for 30 - 50 min. When the midrib of a leaf near the petiole was cut just before measurement, the activity in the injured leaf was decreased but detected even at the apex. This result suggests that the damaged leaf recovered the uptake of water through the lamina. Maximum tracer activities in leaves of unirradiated plant were observed within 10 min, whereas those of irradiated plant at 100 Gy were observed after over 25 min. The final activity of irradiated plant after 30 min was lower than that of unirradiated plant. In case of beans, there was a difference in the absorption behavior of the {sup 18}F-labeled water between unirradiated and irradiated samples. These results show that the system is effective to observe the uptake and transportation of water containing positron emitting tracer for the study of damage and recovery functions of plants. (author)

Using isoelectric focussing and neutron activation analysis to study protein-bound tracer elements

International Nuclear Information System (INIS)

Schmelzer, W.

1976-01-01

A method to determine protein-bound tracer elements was determined by combining a protein separation method with neutron activation analysis. Gel filtration, disk electrophoresis, and isoelectric focussing were studied with regard to their suitability as separation methods. Using isoelectric focussing, human serum protein could be separated with good resolution on a preparative scale. The Se, Cr, Ag, Sc, Fe, Zn, Co, Br, Na, Rb, and Cs contents of the various protein fractions were determined by instrumental neutron activation analysis and by gamma-spectroscopic identification of their long-lived nuclides. Particular attention was paid to the main source of error with this method, i.e. contamination of the proteins in the course of the separation process. Information on the binding of the elements to protein was obtained by comparing the contents in the serum and in the protein separated by gel chromatography. For example, 75% of the Se and 30% of the Cs are bound to protein. Contamination of the protein fractions was studied by means of tracer elements with the element Se, errors due to contamination could be ruled out. The method was modified for the special imvestigation of Se-protein complexes in the serum. The Se content was determined by activation analysis via the short-lived radionuclide sup(77m)Se, this considerably reducing the duration of analysis. With regard to focussing, discrimination was improved in the pH region in which specific Se complexes were found. The activity distribution in fractionated serum protein labelled in vitro with 75 Se in the presence of erythrocytes showed that specific labelling is possible in this way. It is thus possible to study the distribution of Se carrier proteins with the aid of a radiotracer technique. (orig./RB) [de

Chemical Tracer Methods: Chapter 7

Science.gov (United States)

Healy, Richard W.

2017-01-01

Tracers have a wide variety of uses in hydrologic studies: providing quantitative or qualitative estimates of recharge, identifying sources of recharge, providing information on velocities and travel times of water movement, assessing the importance of preferential flow paths, providing information on hydrodynamic dispersion, and providing data for calibration of water flow and solute-transport models (Walker, 1998; Cook and Herczeg, 2000; Scanlon et al., 2002b). Tracers generally are ions, isotopes, or gases that move with water and that can be detected in the atmosphere, in surface waters, and in the subsurface. Heat also is transported by water; therefore, temperatures can be used to trace water movement. This chapter focuses on the use of chemical and isotopic tracers in the subsurface to estimate recharge. Tracer use in surface-water studies to determine groundwater discharge to streams is addressed in Chapter 4; the use of temperature as a tracer is described in Chapter 8.Following the nomenclature of Scanlon et al. (2002b), tracers are grouped into three categories: natural environmental tracers, historical tracers, and applied tracers. Natural environmental tracers are those that are transported to or created within the atmosphere under natural processes; these tracers are carried to the Earth’s surface as wet or dry atmospheric deposition. The most commonly used natural environmental tracer is chloride (Cl) (Allison and Hughes, 1978). Ocean water, through the process of evaporation, is the primary source of atmospheric Cl. Other tracers in this category include chlorine-36 (36Cl) and tritium (3H); these two isotopes are produced naturally in the Earth’s atmosphere; however, there are additional anthropogenic sources of them.

Oblique abdominal muscle activity in response to external perturbations when pushing a cart.

Science.gov (United States)

Lee, Yun-Ju; Hoozemans, Marco J M; van Dieën, Jaap H

2010-05-07

Cyclic activation of the external and internal oblique muscles contributes to twisting moments during normal gait. During pushing while walking, it is not well understood how these muscles respond to presence of predictable (cyclic push-off forces) and unpredictable (external) perturbations that occur in pushing tasks. We hypothesized that the predictable perturbations due to the cyclic push-off forces would be associated with cyclic muscle activity, while external perturbations would be counteracted by cocontraction of the oblique abdominal muscles. Eight healthy male subjects pushed at two target forces and two handle heights in a static condition and while walking without and with external perturbations. For all pushing tasks, the median, the static (10th percentile) and the peak levels (90th percentile) of the electromyographic amplitudes were determined. Linear models with oblique abdominal EMGs and trunk angles as input were fit to the twisting moments, to estimate trunk stiffness. There was no significant difference between the static EMG levels in pushing while walking compared to the peak levels in pushing while standing. When pushing while walking, the additional dynamic activity was associated with the twisting moments, which were actively modulated by the pairs of oblique muscles as in normal gait. The median and static levels of trunk muscle activity and estimated trunk stiffness were significantly higher when perturbations occurred than without perturbations. The increase baseline of muscle activity indicated cocontraction of the antagonistic muscle pairs. Furthermore, this cocontraction resulted in an increased trunk stiffness around the longitudinal axis. Copyright 2010 Elsevier Ltd. All rights reserved.

Holdup time measurement by radioactive tracers in pulp production

International Nuclear Information System (INIS)

Roetzer, H.; Donhoffer, D.

1988-12-01

A batch of pulp was to be labelled before passing two bleaching towers of a pulp plant. Activated glass fibres were used as a tracer, which contained 24-Na with a half-life of 15 hours. It was shown in laboratory tests, that the glass fibres were suitable for transport studies of wood pulp. For use in the tests the fibres were activated and suspended in water. Due to the small diameter of the fibres (2-5 micrometers) this suspension shows physical properties very similar to the pulp. For detection six scintillation probes were mounted at different positions outside the bleaching tower. Radiation protection during the test was very easy due to the low total activity of the tracer material. Residence time distributions for both towers were measured. The successful tracer experiments show, that the method of labelling is suited for investigations of material transport in the pulp and paper industry. 3 figs., 11 refs., 2 tabs. (Author)

In vitro pressure manifolding distribution evaluation of ABThera™ Active Abdominal Therapy System, V.A.C.® Abdominal Dressing System, and Barker’s vacuum packing technique conducted under dynamic conditions

Directory of Open Access Journals (Sweden)

Angel Delgado

2016-01-01

Full Text Available Objectives: Temporary abdominal closure methods allow for management of open abdomens where immediate primary closure is not possible and/or where repeat abdominal entries are necessary. We assessed pressure mapping and fluid extraction efficiency of three open abdomen dressing systems: ABThera™ Active Abdominal Therapy System, V.A.C.® Abdominal Dressing System, and Barker’s vacuum packing technique. Methods: An in vitro test model was designed to simulate physical conditions present in an open abdomen. The model consisted of a rigid rest platform with elevated central region and a flexible outer layer with centrally located incision. Constant −125 mmHg negative pressure was applied according to the type of system, under simulated dynamic conditions, using albumin-based solution with a viscosity of 14 cP. Data were collected by pressure sensors located circumferentially into three concentric zones: Zone 1 (closest to negative pressure source, Zone 2 (immediately outside of manifolding material edge, and Zone 3 (area most distal from negative pressure source. Each value was the result of approximately 100 pressure readings/zone/experiment with a total of three experiments for each system. Results: Pressure distribution of ABThera Therapy was significantly (p < 0.05 superior to Barker’s vacuum packing technique in all three evaluated zones. Similarly, V.A.C. Abdominal Dressing System pressure distribution was significantly (p < 0.05 improved compared to Barker’s vacuum packing technique in all zones. There were no pressure distribution differences in Zone 1 between ABThera Therapy and V.A.C. Abdominal Dressing System; however, in Zones 2 and 3, ABThera Therapy was significantly (p < 0.05 superior to V.A.C. Abdominal Dressing System. Conclusions: These data suggest that all approaches to negative pressure therapy for open abdomen treatment are not equal. Additional research should be conducted to elucidate clinical

Innovative use of a microbial tracer for measuring groundwater through a fractured matrix

International Nuclear Information System (INIS)

Strong-Gunderson, J.M.

1995-01-01

Site characterization for ground water remediation activities is limited by the one's ability to visualize the complexity of the subsurface environment. Currently, a variety of dyes, colloids, gases, etc., are used to monitor and estimate ground water flow and contaminant transport. The author has recently identified a new, innovative colloidal tracer that is a non-hazardous bacterium that is detectable at very low concentrations (ng/kg), and can provide real-time analysis (3--5 min) for measuring colloid transport. The tracer is the ice nucleating active (INA) bacterium Pseudomonas syringae. The assay conditions require measuring the freezing point of the sample (e.g., ground water and soil slurries). Typically, 10--100 microL drops of water will not freeze until -15 to -20 C. However, if the tracer is present the water will freeze at -3 to -7 C. This increase in the freezing point can only be due to the presence of the tracer and this phenomenon is well documented in the plant pathology and low-temperature biology literature but has only now been applied to site characterization and remediation activities. Laboratory experiments have identified the stability of the tracer in the presence of a variety of ground water contaminants (> 100 ppm) and it is stable over a pH range of 2.3--10.0. The tracer has been demonstrated in conjunction with other commonly used tracers at a variety of field sites: (1) a drilling tracer to identify potential cross contamination, and as a colloid/bacterial tracer in (2) a hydrofracturing demonstration, (3) a horizontal recirculation well system, (4) a fractured karst matrix, and (5) a radioactive contaminated site. The data from these demonstrations have provided additional information about site characteristics including faster ground water flow rates than previously identified and due to its low sensitivities better distribution into a clay matrix than estimated by the bromide tracer

Field measurements of tracer gas transport by barometric pumping

International Nuclear Information System (INIS)

Lagus, P.L.; McKinnis, W.B.; Hearst, J.R.; Burkhard, N.R.; Smith, C.F.

1994-01-01

Vertical gas motions induced by barometric pressure variations can carry radioactive gases out of the rubblized region produced by an underground nuclear explosion, through overburden rock, into the atmosphere. To better quantify transit time and amount of transport, field experiments were conducted at two sites on Pahute Mesa, Kapelli and Tierra, where radioactive gases had been earlier detected in surface cracks. At each site, two tracer gases were injected into the rubblized chimney 300-400 m beneath the surface and their arrival was monitored by concentration measurements in gas samples extracted from shallow collection holes. The first ''active'' tracer was driven by a large quantity of injected air; the second ''passive'' tracer was introduced with minimal gas drive to observe the natural transport by barometric pumping. Kapelli was injected in the fall of 1990, followed by Tierra in the fall of 1991. Data was collected at both sites through the summer of 1993. At both sites, no surface arrival of tracer was observed during the active phase of the experiment despite the injection of several million cubic feet of air, suggesting that cavity pressurization is likely to induce horizontal transport along high permeability layers rather than vertical transport to the surface. In contrast, the vertical pressure gradients associated with barometric pumping brought both tracers to the surface in comparable concentrations within three months at Kapelli, whereas 15 months elapsed before surface arrival at Tierra. At Kapelli, a quasisteady pumping regime was established, with tracer concentrations in effluent gases 1000 times smaller than concentrations thought to exist in the chimney. Tracer concentrations observed at Tierra were typically an order of magnitude smaller. Comparisons with theoretical calculations suggest that the gases are traveling through ∼1 millimeter vertical fractures spaced 2 to 4 meters apart. 6 refs., 18 figs., 3 tabs

Randomized trial of amino acid mixture combined with physical activity promotion for abdominal fat reduction in overweight adults

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Ueda K

2018-02-01

Full Text Available Keisuke Ueda,1,2 Hiroyuki Sasai,3 Takehiko Tsujimoto,4 Chiaki Sanbongi,1 Shuji Ikegami,1 Hiroyuki Kobayashi,5 Nobuhiko Shioya,6 Satoru Suzuki,7 Yoshio Nakata5 1Food Science and Technology Research Laboratories, Meiji Co., Ltd, Hachiouji, 2Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, 3Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, 4Faculty of Human Sciences, Shimane University, Matsue, 5Faculty of Medicine, University of Tsukuba, Tsukuba, 6KSO Corporation, Tokyo, 7Shinagawa Season Terrace Health Care Clinic, Tokyo, Japan Purpose: The purpose of this study was to test the efficacy of arginine, alanine, and phenylalanine mixture (A-mix ingestion at 1,500 mg/day in combination with the promotion of physical activity for abdominal fat reduction in overweight adults.Methods: A placebo-controlled, double-blind, parallel-group, randomized trial for 12 weeks combined with a 4-week follow-up period was conducted at a single center in Minato-ku, Tokyo, Japan, between December 2016 and May 2017. Data were analyzed between June and August 2017. The study participants were 200 overweight adults within the age range of 20–64 years. The participants were randomly assigned to the A-mix group (n=100 or a placebo group (n=100 and were administered 500 mL of test beverage containing 1,500 or 0 mg of A-mix, respectively, for 12 weeks. All participants maintained a physically active lifestyle between week 0 and week 12 through monthly sessions of physical activity. The primary outcomes were the 12-week changes in the abdominal total, subcutaneous, and visceral fat areas, as assessed by computed tomography.Results: Of the 200 enrolled participants, 199 (99% accomplished the 12-week intervention and 4-week follow-up period. The per-protocol-based analysis for 194 participants demonstrated that the abdominal total fat area decreased significantly in the A-mix group compared with

Chronic abdominal wall pain misdiagnosed as functional abdominal pain.

Science.gov (United States)

van Assen, Tijmen; de Jager-Kievit, Jenneke W A J; Scheltinga, Marc R; Roumen, Rudi M H

2013-01-01

The abdominal wall is often neglected as a cause of chronic abdominal pain. The aim of this study was to identify chronic abdominal wall pain syndromes, such as anterior cutaneous nerve entrapment syndrome (ACNES), in a patient population diagnosed with functional abdominal pain, including irritable bowel syndrome, using a validated 18-item questionnaire as an identification tool. In this cross-sectional analysis, 4 Dutch primary care practices employing physicians who were unaware of the existence of ACNES were selected. A total of 535 patients ≥18 years old who were registered with a functional abdominal pain diagnosis were approached when they were symptomatic to complete the questionnaire (maximum 18 points). Responders who scored at least the 10-point cutoff value (sensitivity, 0.94; specificity, 0.92) underwent a diagnostic evaluation to establish their final diagnosis. The main outcome was the presence and prevalence of ACNES in a group of symptomatic patients diagnosed with functional abdominal pain. Of 535 patients, 304 (57%) responded; 167 subjects (31%) recently reporting symptoms completed the questionnaire. Of 23 patients who scored above the 10-point cutoff value, 18 were available for a diagnostic evaluation. In half of these subjects (n = 9) functional abdominal pain (including IBS) was confirmed. However, the other 9 patients were suffering from abdominal wall pain syndrome, 6 of whom were diagnosed with ACNES (3.6% prevalence rate of symptomatic subjects; 95% confidence interval, 1.7-7.6), whereas the remaining 3 harbored a painful lipoma, an abdominal herniation, and a painful scar. A clinically relevant portion of patients previously diagnosed with functional abdominal pain syndrome in a primary care environment suffers from an abdominal wall pain syndrome such as ACNES.

Preconcentration method using an activatable yield tracer for neutron activation analysis

International Nuclear Information System (INIS)

Tsukada, Masamichi; Yamamoto, Daijiro; Endo, Kazutoyo; Nakahara, Hiromichi

1991-01-01

Previously, the use of an enriched stable isotope as an activatable yield tracer in preconcentration steps has been tested by use of commercially available enriched 116 Cd and 156 Dy for biological standard reference materials. In the present work, this method has been further applied to the determination of lanthanoid contents in various kinds of samples: one coal fly-ash, three Japanese standard rocks, and eight standard soils. Samples were decomposed by alkali fusion in the preconcentration step. Thirteen elements were determined for coal fly-ash and soil samples, and 14 elements for rocks. The data obtained for coal fly-ash and standard rocks are compared with the data reported in literature. The data for soil samples have been newly determined in the present work. The ordinary instrumental neutron activation analysis and radiochemical neutron activation analysis were also performed to confirm the accuracy and usefulness of the present method. (author) 10 refs.; 4 tabs

The relationship between abdominal muscle activity and pain, disability and fear of movement during standing postural tasks in females with chronic nonspecific low back pain

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Fatemeh Ehsani

2016-10-01

Full Text Available Introduction: It appears that the level of fear of movement changes deep trunk muscle activity in the patients with low back pain (LBP. There is no study to investigate the relationship between deep trunk muscle activity and fear of movement in the patients with LBP. Thus, the purpose of this study was to assess the relationship between abdominal muscle activity and pain, disability and fear of movement during standing postural tasks in females with chronic nonspecific LBP. Materials and Methods: Forty four females participated were asked to maintain their balance during standing on the platform stability levels of Biodex Balance System (BBS. Concurrently, ultrasonography (US data about abdominal muscles thickness measurement were transferred and saved to process offline. The pain intensity, disability and fear of movement were assessed by valid scales and questionnaire. Results: There was not significant correlation between abdominal muscle thickness changes and pain and disability intensity (P>0.05, while significant and inverse correlation between deep abdominal muscle thickness changes and fear of movement was observed in the patients (P<0.05, although this correlation is weak (r= -0.36- -0.32. Conclusion: It seems that increases in fear of movement decrease significantly deep abdominal muscles activity in the patients with LBP. This relationship demonstrates the importance of cognitive behavioral therapy and controlling fear of movement on improvement of deep abdominal muscle activity in the patients with LBP

Uptake of vaporized molybdenum and cesium tracers by molten oxide mixtures as function of free oxygen ion activity

International Nuclear Information System (INIS)

Carmon, B.

1975-11-01

Molten mixtures of oxides containing Ca, Fe, Al, Na and Si were exposed to vaporized Mo-99 and Cs-137 tracers at 1100 and 1300 deg C. Uptake values at 1300 deg C were extrapolated to short heating times. The obtained ''attachment coefficients'' for that temperature are shown to have the relationship (Mo) approximately equal to (Cs)sup(-1/2). The chemical composition of the melts and their oxygen to metal ratio found to affect the uptake of both tracers. This is associated with the cationic field strengths and the free oxygen ion activities in the mixtures. Molybdenum and cesium apparently behave like glass-network forming and glass-network modifying species, respectively. (author)

VACUUM THERAPY VERSUS ABDOMINAL EXERCISES ON ABDOMINAL OBESITY

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Nevein Mohammed Mohammed Gharib

2016-06-01

Full Text Available Background: Obesity is a medical condition that may adversely affect wellbeing and leading to increased incidence of many health problems. Abdominal obesity tends to be associated with weight gain and obesity and it is significantly connected with different disorders like coronary heart disease and type II diabetes mellitus.This study was conducted to investigate the efficacy of vacuum therapy as compared to abdominal exercises on abdominal obesity in overweight and obese women. Methods: Thirtyoverweight and obese women participated in this study with body mass index > 25 kg/m2andwaist circumference ≥ 85 cm. Their ages ranged from 28 - 40 years old.The subjects were excluded if they have diabetes, abdominal infection diseases or any physical limitation restricting exercise ability. They were randomly allocated into two equal groups; group I and group II. Group I received vacuum therapy sessions (by the use of LPG device in addition to aerobic exercise training. Group II received abdominal exercises in addition to the same aerobic exercisesgiven to group I. This study was extended for successive 8 weeks (3 sessions/ week. All subjects were assessed for thickness ofnthe abdominal skin fold, waist circumference and body mass index. Results: The results of this study showeda significant difference between group I and group II post-interventionas regarding to the mean values of waist circumference and abdominal skin fold thickness (p<0.05. Conclusion: It can be concluded that aerobic exercises combined with vacuum therapy (for three sessions/week for successive 8 weeks have a positive effect on women with abdominal obesity in terms of reducing waist circumference and abdominal skin fold thickness.

Tracer applications in oil reservoirs in Brazil

International Nuclear Information System (INIS)

Moreira, R.M.; Ferreira Pinto, A.M.

2004-01-01

Radiotracer applications in oil reservoirs in Brazil started in 1997 at the request of the State Oil Company (Petrobras) at the Carmoplois oilfield. 1 Ci of HTO was injected in a regular five-spot plot and the results obtained were quite satisfactory. Shortly after this test one other request asked for distinguishing the contribution of different injection wells to a production well. It was then realized that other tracers should be available. As a first choice 35 SCN - has been selected since it could be produced at CDTN. An alternative synthesis path was defined which shortened post-irradiation manipulations. The tracer was tested in core samples and a field injection, simultaneously with HTO, was carried out at the Buracica field; again the HTO performed well but 35 SCN - showed up well ahead. Presently the HTO applications are being done on a routine basis. All in all, four tests were performed (some are still ongoing), and the detection limits for both 3 H and 35 S were optimized by refining the sample preparation stage. Lanthanide complexes used as activable tracers are also an appealing option, however core tests performed so far with La-, Ce- and Eu-EDTA indicated some delay of the tracer, so other complexants such as DOTA are to be tried in further laboratory tests and in a field application. Thus, a deeper understanding of their complexation chemistry and carefully conducted tests must be performed before lanthanide complexes can be qualified as reliable oil reservoir tracers. More recently, Petrobras has been asking for partitioning tracers intended for SOR measurement

VISCERAL ABDOMINAL PAIN AND OPPORTUNITIES OF SPASMOLYTIC TREATMENT

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E.A. Kornienko

2008-01-01

Full Text Available Results of treatment of 30 children with visceral abdominal pain caused by different etiological factors with neurotropic selective m9cholinergic antagonist hyoscine butilbromide (buscopan are presented in this article. Two groups of children were treated with hyoscine butilbromide and drotaverine accordingly. Administration of hyoscine butilbromide allows to stop pain in 93% of patients; mean duration of abdominal pain was 3,4 ± 1,2 days (4,2 ± 1,4 days in children treated with drotaverine, р < 0,05. Activity of dyspeptic disorders was decreased at the time of treatment. a tolerance to hyoscine butilbromide was satisfactory, and no adverse events were registered. hyoscine butilbromide is effective in treatment of visceral abdominal pain in children, allowing shortening its duration more actively then drotaverine.Key words: children, visceral abdominal pain, hyoscine butilbromide.

Heterogeneous distribution of a diffusional tracer in the aortic wall of normal and atherosclerotic rabbits

International Nuclear Information System (INIS)

Tsutsui, H.; Tomoike, H.; Nakamura, M.

1990-01-01

Tracer distribution as an index of nutritional support across the thoracic and abdominal aortas in rabbits in the presence or absence of atherosclerotic lesions was evaluated using [ 14 C]antipyrine, a metabolically inert, diffusible indicator. Intimal plaques were produced by endothelial balloon denudation of the thoracic aorta and a 1% cholesterol diet. After a steady intravenous infusion of 200 microCi of [ 14 C]antipyrine for 60 seconds, thoracic and abdominal aortas and the heart were excised, and autoradiograms of 20-microns-thick sections were quantified, using microcomputer-aided densitometry. Regional radioactivity and regional diffusional support, as an index of nutritional flow estimated from the timed collections of arterial blood, was 367 and 421 nCi.g-1 (82 and 106 ml.min-1.100 g-1) in thoracic aortic media of the normal and atherosclerotic rabbits, respectively. Radioactivity at the thickened intima was 179 nCi.g-1 (p less than 0.01 versus media). The gruel was noted at a deeper site within the thickened intima, and diffusional support here was 110 nCi.g-1 (p less than 0.01 versus an average radioactivity at the thickened intima). After ligating the intercostal arteries, regional tracer distribution in the media beneath the fibrofatty lesion, but not the plaque-free intima, was reduced to 46%. Thus, in the presence of advanced intimal thickening, the heterogeneous distribution of diffusional flow is prominent across the vessel wall, and abluminal routes are crucial to meet the increased demands of nutritional requirements

Radio-isotopic tracers

International Nuclear Information System (INIS)

Wolfangel, R.G.

1976-01-01

The invention concerns the dispersions that may be used for preparing radio-isotopic tracers, technetium labelled dispersions, processes for preparing these dispersions and their use as tracers. Technetium 99m sulphur colloids are utilized as scintillation tracers to give a picture of the reticulo-endothelial system, particularly the liver and spleen. A dispersion is provided which only requires the addition of a radioactive nuclide to form a radioactively labelled dispersion that can be injected as a tracer. It is formed of a colloid of tin sulphur dispersed in an aqueous buffer solution. Such a reagent has the advantage of being safe and reliable and is easier to use. The colloid can be prepared more quickly since additions of several different reagents are avoided. There is no need to heat up and no sulphuretted hydrogen, which is a toxic gas, is used [fr

Quantitative measurement of maritime sediment movement using radioactive tracers

International Nuclear Information System (INIS)

Makovski, E.; Grissener, G.

1967-01-01

The quantitative method described in the paper involves burying appropriate detectors over a given area of the sea bottom, the detectors being connected to recording equipment which is itself buried in the sediment or situated on the shore. Detectors arranged in this way are covered by a certain layer of radioactive sediment whose activity is proportional to its mass. Before the labelled sediments are removed, their initial activity is measured, and then, as the covering is removed, measurements are made of the gradual decrease in activity corresponding to loss of the surface layer of the bottom deposit area under investigation, expressed in g/cm 2 . The tracers used in the investigations discussed were natural ones such as sea with 31 Si and artificial ones such as activated fragments of sodium glass (with a 6.5% admixture of Fe 2 O 3 ) with 24 Na . The proportional dependence of activity on mass has been confirmed for both tracers; this is an essential point for a tracer intended for quantitative measurements. This proportionality is very well maintained if a sample of highly active sediment is introduced into a large mass of inactive sediments (10 -2 - 10 -3 ). The concluding section describes the advantages of this method as a possible way of using radioisotopes with a short half-life and a low total activity of the order of a few millicuries. (author)

Activation energy of tracer-diffusion of manganese ions (Mn2+) in alkali metal chloride solutions

International Nuclear Information System (INIS)

Borhade, A.V.

2000-01-01

The activation energy of the tracer diffusion of Mn 2+ ions in alkali chloride solutions (0.1M) has been determined in agar gel medium (1-2.5%) over the temperature range of 25 - 45 deg C. The decrease in the value of the Arrhenius parameters, E and D 0 , with gel percentage is explained on the basis of the transition state theory. Further, the activation energy as a function of electrolyte concentration is also investigated using 1% agar gel in the temperature range of 25 - 45 deg C. In both the cases, the activation energies are determined by the least square fitting of the diffusion coefficient data obtained at various temperatures through the Arrhenius plots. (author)

Quadratic tracer dynamical models tobacco growth

International Nuclear Information System (INIS)

Qiang Jiyi; Hua Cuncai; Wang Shaohua

2011-01-01

In order to study the non-uniformly transferring process of some tracer dosages, we assume that the absorption of some tracer by tobacco is a quadratic function of the tracer quantity of the tracer in the case of fast absorption, whereas the exclusion of the tracer from tobacco is a linear function of the tracer quantity in the case of slow exclusion, after the tracer is introduced into tobacco once at zero time. A single-compartment quadratic dynamical model of Logistic type is established for the leaves of tobacco. Then, a two-compartment quadratic dynamical model is established for leaves and calms of the tobacco. Qualitative analysis of the models shows that the tracer applied to the leaves of the tobacco is excluded finally; however, the tracer stays at the tobacco for finite time. Two methods are also given for computing the parameters in the models. Finally, the results of the models are verified by the 32 P experiment for the absorption of tobacco. (authors)

Tracers and tracing methods

International Nuclear Information System (INIS)

Leclerc, J.P.

2001-01-01

The first international congress on 'Tracers and tracing methods' took place in Nancy in May 2001. The objective of this second congress was to present the current status and trends on tracing methods and their applications. It has given the opportunity to people from different fields to exchange scientific information and knowledge about tracer methodologies and applications. The target participants were the researchers, engineers and technologists of various industrial and research sectors: chemical engineering, environment, food engineering, bio-engineering, geology, hydrology, civil engineering, iron and steel production... Two sessions have been planned to cover both fundamental and industrial aspects: 1)fundamental development (tomography, tracer camera visualization and particles tracking; validation of computational fluid dynamics simulations by tracer experiments and numerical residence time distribution; new tracers and detectors or improvement and development of existing tracing methods; data treatments and modeling; reactive tracer experiments and interpretation) 2)industrial applications (geology, hydrogeology and oil field applications; civil engineering, mineral engineering and metallurgy applications; chemical engineering; environment; food engineering and bio-engineering). The program included 5 plenary lectures, 23 oral communications and around 50 posters. Only 9 presentations are interested for the INIS database

Tracer dating and ocean ventilation

International Nuclear Information System (INIS)

Thiele, G.; Sarmiento, J.L.

1990-01-01

The interpretation of transient tracer observations depends on difficult to obtain information on the evolution in time of the tracer boundary conditions and interior distributions. Recent studies have attempted to circumvent this problem by making use of a derived quantity, age, based on the simultaneous distribution of two complementary tracers, such as tritium and its daughter, helium 3. The age is defined with reference to the surface such that the boundary condition takes on a constant value of zero. The authors use a two-dimensional model to explore the circumstances under which such a combination of conservation equations for two complementary tracers can lead to a cancellation of the time derivative terms. An interesting aspect of this approach is that mixing can serve as a source or sink of tracer based age. The authors define an idealized ventilation age tracer that is conservative with respect to mixing, and they explore how its behavior compares with that of the tracer-based ages over a range of advective and diffusive parameters

Evaluation of Forty-Nine Patients with Abdominal Tuberculosis

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Murat Kilic

2014-12-01

Full Text Available Aim: Abdominal tuberculosis is an uncommon form of extrapulmonary infection. In this study, we aimed to highlight the nonspecific clinical presentations and diagnostic difficulties of abdominal tuberculosis. Material and Method: Clinical features, diagnostic methods, and the therapeutic outcomes of 49 patients diagnosed as abdominal tuberculosis between 2003 and 2014 were retrospectively analyzed. Results: The patients were classified into four subgroups including peritoneal (28, nodal (14, intestinal (5, and solid organ tuberculosis (2. The most frequent symptoms were abdominal pain, abdominal distention and fatique. Ascites appeared to be the most frequent clinical finding. Ascites and enlarged abdominal lymph nodes were the most frequent findings on ultrasonography and tomography. Diagnosis of abdominal tuberculosis was mainly depended on histopathology of ascitic fluid and biopsies from peritoneum, abdominal lymph nodes or colonoscopic materials. Forty patients healed with standart 6-month therapy while extended treatment for 9-12 months was needed in 8 whom had discontinued drug therapy and had persistent symptoms and signs. One patient died within the treatment period due to disseminated infection. Discussion: The diagnosis of abdominal tuberculosis is often difficult due to diverse clinical presentations. The presence of ascites, personal/familial/contact history of tuberculosis, and coexisting active extraabdominal tuberculosis are the most significant marks in diagnosis. Diagnostic laparoscopy and tissue sampling seem to be the best diagnostic approach for abdominal tuberculosis.

Movement of iodine and rain water from the atmosphere to the plant - soil - water system by the activable tracer techniques

International Nuclear Information System (INIS)

Yuita, Kouichi

1996-01-01

Iodine is one of the important elements in the environmental and agricultural sciences. It is requested to elucidate the long-term behavior of iodine in the atmosphere - soil·plant - soil water system. We developed the new tracer method, in which iodine released into the atmosphere from the stack of iodine manufacturing plant in Chiba prefecture was used as the activable tracer. Using this method, we traced the direct deposition of iodine in atmosphere onto the plant tops and the penetration of fallout iodine into soil in an open air over a long period. A quantitative evaluation of recharge function of water resources in agricultural and forest lands of Japan was eagerly requested from the nation. For it, we developed the new Br - tracer method combined with the soil water sampling system with the alumina porous ceramic cup. This tracer method was successfully applied to the agricultural and forest land in the catchment area of Sakawa river in Kanagawa prefecture. And the infiltration rate of the rain water and irrigation water, from the soil surface to the dept of 3m of the soil horizon in the forest land, tea garden and paddy field was quantitatively measured during two years. (J.P.N.)

In Situ Tracer method for establishing the presence and predicting the activity of heavy metal-reducing microbes in the subsurface. Final Report

Energy Technology Data Exchange (ETDEWEB)

Hatfield, K.

2003-07-01

Tracer method to establish presence and distribution of chromium reducing microbes. The primary objective of this research was to establish an in situ tracer method for detecting the presence. distribution. and activity of subsurface heavy metal-reducing microorganisms. Research focused on microbial systems responsible for the reduction of chromium and a suite of biotracers coupled to the reduction process. The tracer method developed may be used to characterize sites contaminated with chromium or expedite bioremediation: and although research focused on chromium. the method can be easily extended to other metals, organics, and radionuclides. This brief final report contains three major sections. The first identifies specific products of the research effort such as students supported and publications. The second section briefly presents major research findings, while the last section summarizes the overall research effort.

Study on bioavailability of dietary iron of women by using activable isotopic tracer and neutron activation analysis techniques

International Nuclear Information System (INIS)

Zhang Yangmei; Ni Bangfa; Tian Weizhi; Wang Pingsheng; Cao Lei

2002-01-01

The bioavailability of diet iron of 10 healthy young women in Beijing area is studied by using two enriched isotopes 54 Fe and 58 Fe, and neutron activation analysis techniques. The abundance of 54 Fe and 58 Fe is 61.4% and 23.4%, respectively. In additional, the atomic absorption spectrometry is employed to measure total iron in fecal samples. Dysprosium, rarely absorbed by human body, is used to monitor the residence time of tracer isotopes in order to collect the fecal samples completely. The results show that the bioavailability of dietary iron in young women is (14.9 +- 3.9)%

Activation amplitude and temporal synchrony among back extensor and abdominal muscles during a controlled transfer task: comparison of men and women.

Science.gov (United States)

Hubley-Kozey, Cheryl L; Butler, Heather L; Kozey, John W

2012-08-01

Muscle synergies are important for spinal stability, but few studies examine temporal responses of spinal muscles to dynamic perturbations. This study examined activation amplitudes and temporal synergies among compartments of the back extensor and among abdominal wall muscles in response to dynamic bidirectional moments of force. We further examined whether responses were different between men and women. 19 women and 18 men performed a controlled transfer task. Surface electromyograms from bilateral sites over 6 back extensor compartments and 6 abdominal wall muscle sites were analyzed using principal component analysis. Key features were extracted from the measured electromyographic waveforms capturing amplitude and temporal variations among muscle sites. Three features explained 97% of the variance. Scores for each feature were computed for each measured waveform and analysis of variance found significant (pWomen had more differences among muscle sites than men for the lateral flexion moment feature. For the abdominal wall muscles the oblique muscles responded with synergies related to fiber orientation, with women having higher amplitudes and more responsiveness to the lateral flexion moment than men. Synergies between the abdominal and back extensor sites as the moment demands change are discussed. These findings illustrate differential activation among erector spinae compartments and abdominal wall muscle sites supporting a highly organized pattern of response to bidirectional external moments with asynchronies more apparent in women. Copyright © 2012 Elsevier B.V. All rights reserved.

Abdominal emergencies

International Nuclear Information System (INIS)

Raissaki, M.

2012-01-01

children and young individuals with abdominal pain. Sensitivity and specificity for US in diagnosing intussusception, midgut volvulus, urinary tract abnormalities and appendicitis is over 90%. US, occasionally with x-rays, usually suffice for an accurate diagnosis. Upper GI contrast studies are indicated in suspected malrotation, volvulus and atypical high obstruction cases. Lower GI contrast studies are indicated in low/colonic obstruction. CT and/or MRI should be reserved for atypical, complex cases when US and conventional radiography are equivocal or inconclusive. The radiologist should engage oneself to act immediately, consider and actively exclude those diagnoses that could be a threat to the child's health or life. The appropriate modality should be chosen and proper technique should be applied. Radiologists should function as clinicians, take initiative and discuss options and alternative diagnoses. Lack of experience should not delay performance of tests. Our job is finished when a diagnostic test has a written report provided that we make sure the child is managed properly.

An abdominal tuberculosis case mimicking an abdominal mass

African Journals Online (AJOL)

An abdominal tuberculosis case mimicking an abdominal mass. Derya Erdog˘ an a. , Yasemin Ta ¸scı Yıldız b. , Esin Cengiz Bodurog˘lu c and Naciye Go¨nu¨l Tanır d. Abdominal tuberculosis is rare in childhood. It may be difficult to diagnose as it mimics various disorders. We present a 12-year-old child with an unusual ...

Patterns of Brain Activation and Meal Reduction Induced by Abdominal Surgery in Mice and Modulation by Rikkunshito.

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Lixin Wang

Full Text Available Abdominal surgery inhibits food intake and induces c-Fos expression in the hypothalamic and medullary nuclei in rats. Rikkunshito (RKT, a Kampo medicine improves anorexia. We assessed the alterations in meal microstructure and c-Fos expression in brain nuclei induced by abdominal surgery and the modulation by RKT in mice. RKT or vehicle was gavaged daily for 1 week. On day 8 mice had no access to food for 6-7 h and were treated twice with RKT or vehicle. Abdominal surgery (laparotomy-cecum palpation was performed 1-2 h before the dark phase. The food intake and meal structures were monitored using an automated monitoring system for mice. Brain sections were processed for c-Fos immunoreactivity (ir 2-h after abdominal surgery. Abdominal surgery significantly reduced bouts, meal frequency, size and duration, and time spent on meals, and increased inter-meal interval and satiety ratio resulting in 92-86% suppression of food intake at 2-24 h post-surgery compared with control group (no surgery. RKT significantly increased bouts, meal duration and the cumulative 12-h food intake by 11%. Abdominal surgery increased c-Fos in the prelimbic, cingulate and insular cortexes, and autonomic nuclei, such as the bed nucleus of the stria terminalis, central amygdala, hypothalamic supraoptic (SON, paraventricular and arcuate nuclei, Edinger-Westphal nucleus (E-W, lateral periaqueduct gray (PAG, lateral parabrachial nucleus, locus coeruleus, ventrolateral medulla and nucleus tractus solitarius (NTS. RKT induced a small increase in c-Fos-ir neurons in the SON and E-W of control mice, and in mice with surgery there was an increase in the lateral PAG and a decrease in the NTS. These findings indicate that abdominal surgery inhibits food intake by increasing both satiation (meal duration and satiety (meal interval and activates brain circuits involved in pain, feeding behavior and stress that may underlie the alterations of meal pattern and food intake inhibition

Suitability of tracers

International Nuclear Information System (INIS)

Klotz, D.

1999-01-01

Hydrological tracer techniques are a means of making statements on the direction and speed of underground water. One of the simpler tasks is to find out whether there is hydrological communication between two given points. This requires a determination of the direction of flow, which places less exacting demands on the properties of the tracer than does the task of determining the flow velocity of underground water. Tracer methods can serve to infer from flow velocity the distance (flow) velocity, which is defined as the ratio between the distance between two points located in flow direction and the actual time it takes water to flow from one to the other [de

Application of separable parameter space techniques to multi-tracer PET compartment modeling

International Nuclear Information System (INIS)

Zhang, Jeff L; Michael Morey, A; Kadrmas, Dan J

2016-01-01

Multi-tracer positron emission tomography (PET) can image two or more tracers in a single scan, characterizing multiple aspects of biological functions to provide new insights into many diseases. The technique uses dynamic imaging, resulting in time-activity curves that contain contributions from each tracer present. The process of separating and recovering separate images and/or imaging measures for each tracer requires the application of kinetic constraints, which are most commonly applied by fitting parallel compartment models for all tracers. Such multi-tracer compartment modeling presents challenging nonlinear fits in multiple dimensions. This work extends separable parameter space kinetic modeling techniques, previously developed for fitting single-tracer compartment models, to fitting multi-tracer compartment models. The multi-tracer compartment model solution equations were reformulated to maximally separate the linear and nonlinear aspects of the fitting problem, and separable least-squares techniques were applied to effectively reduce the dimensionality of the nonlinear fit. The benefits of the approach are then explored through a number of illustrative examples, including characterization of separable parameter space multi-tracer objective functions and demonstration of exhaustive search fits which guarantee the true global minimum to within arbitrary search precision. Iterative gradient-descent algorithms using Levenberg–Marquardt were also tested, demonstrating improved fitting speed and robustness as compared to corresponding fits using conventional model formulations. The proposed technique overcomes many of the challenges in fitting simultaneous multi-tracer PET compartment models. (paper)

Noninvasive experimental determination of the individual kidney filtration fraction by means of a dual-tracer technique. [/sup 131/I and /sup 99m/Tc tracer techniques

Energy Technology Data Exchange (ETDEWEB)

Assailly, J.; Pavel, D.G.; Bader, C.; Chanard, J.; Ryerson, T.W.; Cotard, J.P.; Funck-Brentano, J.L.

1977-07-01

A noninvasive method for measurement of the individual kidney filtration fraction (FF) is presented, based on an analysis of the early rise of the kidneys' time-activity curves obtained after simultaneous injection of tubular (/sup 131/I) ortho-iodohippurate and glomerular (Tc-99m DTPA) tracers. The analysis is based on the assumption that an insignificant amount of tracer leaves the kidney during the first few moments following injection. Therefore the kidney activity during this period is directly proportional to the integral of the blood (heart) activity. The dual-tracer technique allows the direct calculation of the ratio of glomerular to tubular clearances, i.e., the FF. In vivo studies were performed on 12 dogs, including normals as well as others with acute ureteral ligation or Benemid-induced tubular blockade. The calculated FF correlated well with the FF obtained from single-shot clearances performed simultaneously. We conclude that the FF can be calculated directly for each kidney, noninvasively, from the early part of the tubular and glomerular time-activity curves by noninvasive external detection.

Is abdominal wall contraction important for normal voiding in the female rat?

Directory of Open Access Journals (Sweden)

Boone Timothy B

2007-03-01

Full Text Available Abstract Background Normal voiding behavior in urethane-anesthetized rats includes contraction of the abdominal wall striated muscle, similar to the visceromotor response (VMR to noxious bladder distension. Normal rat voiding requires pulsatile release of urine from a pressurized bladder. The abdominal wall contraction accompanying urine flow may provide a necessary pressure increment for normal efficient pulsatile voiding. This study aimed to evaluate the occurrence and necessity of the voiding-associated abdominal wall activity in urethane-anesthetized female rats Methods A free-voiding model was designed to allow assessment of abdominal wall activity during voiding resulting from physiologic bladder filling, in the absence of bladder or urethral instrumentation. Physiologic diuresis was promoted by rapid intravascular hydration. Intercontraction interval (ICI, voided volumes and EMG activity of the rectus abdominis were quantified. The contribution of abdominal wall contraction to voiding was eliminated in a second group of rats by injecting botulinum-A (BTX, 5 U into each rectus abdominis to induce local paralysis. Uroflow parameters were compared between intact free-voiding and BTX-prepared animals. Results Abdominal wall response is present in free voiding. BTX preparation eliminated the voiding-associated EMG activity. Average per-void volume decreased from 1.8 ml to 1.1 ml (p Conclusion The voiding-associated abdominal wall response is a necessary component of normal voiding in urethane anesthetized female rats. As the proximal urethra may be the origin of the afferent signaling which results in the abdominal wall response, the importance of the bladder pressure increment due to this response may be in maintaining a normal duration intermittent pulsatile high frequency oscillatory (IPHFO/flow phase and thus efficient voiding. We propose the term Voiding-associated Abdominal Response (VAR for the physiologic voiding-associated EMG/abdominal

Uptake and transport of positron-emitting tracer (18F) in plants

International Nuclear Information System (INIS)

Kume, Tamikazu; Matsuhashi, Shinpei; Shimazu, Masamitsu

1997-01-01

The transport of a positron-emitting isotope introduced into a plant was dynamically followed by a special observation apparatus called Positron-Emitting Tracer Imaging System' to observe the damage and recovery functions of plants in vivo. In the system, annihilation γ-rays from the positron emitter are detected with two planar detectors (5 x 6 cm 2 ). The water containing ca. 5 MBq/ml of 18 F was fed to the cut stem of soybean for 2 min and then the images of tracer activity were recorded for 30-50 min. When the midrib of a leaf near the petiole was cut just before measurement, the activity in the injured leaf was decreased but detected even at the apex. This result suggests that the damaged leaf recovered the uptake of water through the lamina. Maximum tracer activities in leaves of unirradiated plant were observed within 10 min, whereas those of irradiated plant at 100 Gy were observed after over 25 min. The final activity of irradiated plant after 30 min was lower than that of unirradiated plant. In case of beans, there was a difference in the absorption behavior of the 18 F-labeled water between unirradiated and irradiated samples. These results show that the system is effective to observe the uptake and transportation of water containing positron emitting tracer for the study of damage and recovery functions of plants. (Author)

Use of radioactive tracers in dynamic sedimentology

International Nuclear Information System (INIS)

Tola, Francois.

1982-01-01

In the first part, developments in the use of radioactive tracers in sedimentology are recalled together with the corresponding fields of application and the identities of the main users. The state-of-the-art in France is also discussed; The main characteristics of the method are then described and compared with those of more classical methods. The results that can be obtained with tracer methods are then outlined. The criteria employed to establish the granulometry characteristics of the tracer, the particular radioisotope to be used, and the masses and activities involved, are treated. A list is then given of the main isotopes available in France and their characteristics. The various different labelling techniques employed are studied together with their respective advantages and disadvantages. The special case of pelitic sediments is mentioned. The use of reduced model isotope generators, double labelling and applications to studies of the mud plug in the Gironde Estuary are also discussed. The methods and materials used for injecting and detecting tracers are described, emphasis being given to the economic factors associated with the use of radioactive tracers in sedimentology. The second part of the report contains two chapters: - studies of transport by driftage: presentation and analysis of results and the application of the Count Rate Balance method to obtain quantitative information on transport; - studies of in-suspension transport of fine sediments in the sea: the procedures adopted from the moment when the tracer is introduced up to the time when the results are analyzed and interpreted, enables the trajectories and mean velocities of the transported sediments to be determined together with their degree of dilution and their settling speeds and rates; it is also possible to investigate the evolution and horizontal dispersion of the sediments in this way. Results from recent experiments are presented in both parts of the report

School-based study found that physical activity and aerobic fitness predicted increases in total body fat and abdominal fat at a mean age of 9.8 years.

Science.gov (United States)

Danielson, Anton; Thorsson, Ola; Karlsson, Magnus K; Wollmer, Per; Andersen, Lars B; Dencker, Magnus

2018-02-22

We assessed whether baseline measurements of physical activity, aerobic fitness, body fat and abdominal fat were predictors of changes in body fat measurements over a two-year period. The study comprised of 204 children aged 9.8 ± 0.6 years with a normal body mass distribution, who recruited from four schools in middle-class areas of Malmö, Sweden, from 2001 to 2004. Peak oxygen uptake and physical activity were measured at baseline. Body fat was measured by dual-energy X-ray absorptiometry at baseline and two years later. Physical activity, aerobic fitness and total body fat or abdominal fat were predictors of change in total body fat or abdominal fat over a period of two years. Changes in the percentage of body fat were not related to any of the baseline measurements. Our two-year follow-up of children with a mean age of 9.8 years at baseline showed that physical activity, aerobic fitness and body fat or abdominal fat predicted changes in total body fat or abdominal fat, but not the percentage of body fat. ©2018 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Packet Tracer network simulator

CERN Document Server

Jesin, A

2014-01-01

A practical, fast-paced guide that gives you all the information you need to successfully create networks and simulate them using Packet Tracer.Packet Tracer Network Simulator is aimed at students, instructors, and network administrators who wish to use this simulator to learn how to perform networking instead of investing in expensive, specialized hardware. This book assumes that you have a good amount of Cisco networking knowledge, and it will focus more on Packet Tracer rather than networking.

Proceedings of the atmospheric tracers and tracer application workshop

International Nuclear Information System (INIS)

Barr, S.; Gedayloo, T.

1979-12-01

In addition to presentations by participating members a general discussion was held in order to summarize and outline the goals and objectives of the workshop. A number of new low level background tracers such as heavy methanes, perfluorocarbons, multiply labeled isotopes such as 13 C 18 O 2 , helium 3, in addition to sample collection techniques and analytical methods for various tracers were discussed. This report is a summary of discussions and papers presented at this workshop

An improved method for analysis of In-EDTA, I- and Br- used as active tracers in hydrological studies

International Nuclear Information System (INIS)

Stanescu, S.P.; Spiridon, S.

1992-01-01

Neutron activation analysis combined with chemical preconcentration of the elements in water samples can give a high sensitivity in the determination of concentrations for In-EDTA, I - and Br - used as active tracers in hydrological studies. The authors have developed an improved method of analysis which is sensitive, selective and applicable to a wide range of underground and surface water samples including those having a high concentration of manganese ions. (author) 6 refs.; 2 figs.; 1 tab

Fifty years of radiochemical tracers

International Nuclear Information System (INIS)

Evans, E.A.

1992-01-01

During the past 50 years radiochemical tracers, usually in the form of isotopically labelled organic compounds, have been essential tools to further advance our knowledge at the frontiers of a great variety of scientific developments in the life sciences. This plenary lecture reviews necessarily selected highlights in the synthesis and applications of such radiochemical tracers. Included are examples where important advances, made possible by using radiochemicals, have contributed to improving the quality of life on this planet. The principal radioisotopes involved, 14 C, 3 H, 35 S, 32 P, 125 I, are all relatively safe to handle and are commercially available at maximum theoretical specific activity (carrier free). The compounds labeled with these radioisotopes are used in many fields of research which include biosynthesis and biotechnology studies, cell biology, drug metabolism, clinical research and environmental applications, and are briefly reviewed. (author). 55 refs

Intra-abdominal hypertension and abdominal compartment syndrome in association with ruptured abdominal aortic aneurysm in the endovascular era: vigilance remains critical.

Science.gov (United States)

Bozeman, Matthew C; Ross, Charles B

2012-01-01

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are common complications of ruptured abdominal aortoiliac aneurysms (rAAAs) and other abdominal vascular catastrophes even in the age of endovascular therapy. Morbidity and mortality due to systemic inflammatory response syndrome (SIRS) and multiple organ failure (MOF) are significant. Recognition and management of IAH are key critical care measures which may decrease morbidity and improve survival in these vascular patients. Two strategies have been utilized: expectant management with prompt decompressive laparotomy upon diagnosis of threshold levels of IAH versus prophylactic, delayed abdominal closure based upon clinical parameters at the time of initial repair. Competent management of the abdominal wound with preservation of abdominal domain is also an important component of the care of these patients. In this review, we describe published experience with IAH and ACS complicating abdominal vascular catastrophes, experience with ACS complicating endovascular repair of rAAAs, and techniques for management of the abdominal wound. Vigilance and appropriate management of IAH and ACS remains critically important in decreasing morbidity and optimizing survival following catastrophic intra-abdominal vascular events.

Needle Type Solid State Detectors for In-Vivo Measurement of Tracer Activity

Energy Technology Data Exchange (ETDEWEB)

Lauber, A [AB Atomenergi, Nykoeping (Sweden); Wolgast, W [Univ. of Uppsala (Sweden). Inst. of Physiology and Medical Biophysics

1970-07-15

A set of miniature detector probes for in-vivo-measurement of beta and gamma tracer activity is described. The probes use a lithium-compensated p-i-n silicon detector as sensing element. The standard 'needle probe' contains a cylindrical detector 0.9 mm in diameter and 3 mm long, enclosed in a stainless steel tube 1.1 mm in outer diameter and with walls 0. 05 mm thick. For particular applications several modified types have been developed: probes with larger sensing elements, probes with extra thin walls for low-energy beta detection, probes with two or three sensing elements in the same needle and probes containing a movable sensing element. This report describes the construction and the properties of the different needle probes.

Needle Type Solid State Detectors for In-Vivo Measurement of Tracer Activity

International Nuclear Information System (INIS)

Lauber, A.; Wolgast, W.

1970-07-01

A set of miniature detector probes for in-vivo-measurement of beta and gamma tracer activity is described. The probes use a lithium-compensated p-i-n silicon detector as sensing element. The standard 'needle probe' contains a cylindrical detector 0.9 mm in diameter and 3 mm long, enclosed in a stainless steel tube 1.1 mm in outer diameter and with walls 0. 05 mm thick. For particular applications several modified types have been developed: probes with larger sensing elements, probes with extra thin walls for low-energy beta detection, probes with two or three sensing elements in the same needle and probes containing a movable sensing element. This report describes the construction and the properties of the different needle probes

Use of artificial tracers in hydrology

International Nuclear Information System (INIS)

1991-05-01

The IAEA has convened an Advisory Group Meeting with the following objectives: To define the role of artificial radioactive tracers for water tracing in comparison with other non-radioactive tracers. To evaluate the real needs of artificial radioactive tracers in hydrology. To identify the fields for which artificial radioactive tracers are useful as well as those in which they can be substituted by other tracers. To discuss the strategy to be adopted to overcome the difficulties derived from the restrictions on the use of radioactive tracers in hydrology. The meeting was held at IAEA Headquarters from 19 to 22 March 1990, and was attended by 30 participants from 15 Member States. The conclusions and recommendations are that the use of artificial radioactive tracers should be restricted to cases where other tracers cannot be used or do not provide the same quality of information. Tritium, iodine-131, bromine-82, chromium-51 in the form of Cr-EDTA, technetium-99m obtained from 99 Mo-generators and gold-198 as an adsorbable tracer are, practically, the only radionuclides used for water tracing. The use of other radionuclides for this purpose does not appear to be necessary, possible and/or convenient. Refs, figs and tabs

Abdominal trauma

International Nuclear Information System (INIS)

Giordany, B.R.

1985-01-01

Abdominal injury is an important cause of morbidity and mortality in childhood. Ten percent of trauma-related deaths are due to abdominal injury. Thousands of children are involved in auto accidents annually; many suffer severe internal injury. Child abuse is a second less frequent but equally serious cause of internal abdominal injury. The descriptions of McCort and Eisenstein and their associates in the 1960s first brought to attention the frequency and severity of visceral injury as important manifestations of the child abuse syndrome. Blunt abdominal trauma often causes multiple injuries; in the past, many children have been subjected to exploratory surgery to evaluate the extent of possible hidden injury. Since the advent of noninvasive radiologic imaging techniques including radionuclide scans and ultrasound and, especially, computed tomography (CT), the radiologist has been better able to assess (accurately) the extent of abdominal injury and thus allow conservative therapy in many cases. Penetrating abdominal trauma occurs following gunshot wounds, stabbing, and other similar injury. This is fortunately, a relatively uncommon occurrence in most pediatric centers and will not be discussed specifically here, although many principles of blunt trauma diagnosis are valid for evaluation of penetrating abdominal trauma. If there is any question that a wound has extended intraperitonelly, a sinogram with water-soluble contrast material allows quick, accurate diagnosis. The presence of large amounts of free intraperitoneal gas suggests penetrating injury to the colon or other gas-containing viscus and is generally considered an indication for surgery

Process Analysis in Chemical Plant by Means of Radioactive Tracers

Energy Technology Data Exchange (ETDEWEB)

Hirayama, T.; Hamada, K.; Osada, K. [Showa Denko K.K., Tokyo (Japan)

1967-06-15

Following the movement of solids and fluids is important in chemical processes to determine mixing efficiency and residence time. Since it is necessary to follow many complex substances such as raw materials, intermediates and reactants in plant investigations, it is often necessary to ascertain whether the behaviour of the radioisotope tracer and the substance to be traced are identical. The most difficult problem is to determine the best method of labelling, a factor which is a substantial key to the success of an experiment. Usually, there are three labelling techniques: radioisotope labelling, pre-.activation of the material and post-activation of the material. This paper deals with practical examples of the double-tracer technique, a combination of conventional radioisotope labelling and post-activation methods by means of activation analysis. In process analysis by means of tracers, a practical measurement method should also be devised and developed for each experiment. Phosphorus-32 and gold (non-radioactive) were used to measure retention time in a carbon-black plant. The radioisotope was pumped into a feed-stock pipe positioned before the reactor and samples were taken from each process of the plant, including the bag filter, mixer and product tank. After sampling from each step of the process, {sup 32}P in a semi-infinite powder sample was measured in situ by beta counting, and the gold was measured by gamma counting after activating the sample in a reactor. The experiment showed that both tracers had the same residence time, which was shorter than expected. Useful data were also obtained from the dispersion pattern of the material flow for future operation controls, including the time required to change from one grade of product to another. Practical tracer techniques to measure mixing characteristics in high-speed gas flows using {sup 85}Kr have been developed. A study of the measurement method was conducted by calculating the differential values of

Relative distance between tracers as a measure of diffusivity within moving aggregates

Science.gov (United States)

Pönisch, Wolfram; Zaburdaev, Vasily

2018-02-01

Tracking of particles, be it a passive tracer or an actively moving bacterium in the growing bacterial colony, is a powerful technique to probe the physical properties of the environment of the particles. One of the most common measures of particle motion driven by fluctuations and random forces is its diffusivity, which is routinely obtained by measuring the mean squared displacement of the particles. However, often the tracer particles may be moving in a domain or an aggregate which itself experiences some regular or random motion and thus masks the diffusivity of tracers. Here we provide a method for assessing the diffusivity of tracer particles within mobile aggregates by measuring the so-called mean squared relative distance (MSRD) between two tracers. We provide analytical expressions for both the ensemble and time averaged MSRD allowing for direct identification of diffusivities from experimental data.

Tracer measured substrate turnover requires arterial sampling downstream of infusion site

International Nuclear Information System (INIS)

Stanley, W.C.; Neese, R.A.; Gertz, E.W.; Wisneski, J.A.; Morris, D.L.; Brooks, G.A.

1986-01-01

Measurement of metabolite turnover (Rt) with radioactive tracers is done by either infusing tracer venously and sampling specific activity (SA) arterially (V-A modes), or by infusing into the aorta and sampling venous blood (A-V mode). Using the Fick principle, the necessity for using the V-A mode can be demonstrated. If tracer is infused into the left ventricle, in a steady state the Rt is the product of arterial trace concentration, the cardiac output, and the tracer extraction ratio for the whole body. This is expressed as: Rt = Ca x Qx ((*Ca - *Cv)/*Ca) (Eq1) where C=trace concentration (μmol/ml), *C=tracer conc. (dpm/ml), a=arterial, v-=mixed venous, and Q=cardiac output (ml/min). Rearranging the equation: Rt = Qx(*Ca - *Cv)/SAa = F/SAa (Eq2) where SAa is *Ca/Ca, and Qx (*Ca-*Cv) equals the infusion rate (F). The authors compared Eqs1 and 2 (Rt = F/SAa) in 3 anesthetized dogs in which [1- 14 C] lactate was infused into the left ventricle, and blood was sampled arterially downstream from the infusion site and in the pulmonary artery. Eqs 1 and 2 gave similar results for Rt (45.9 vs. 43.9 μmol/kg min), while substituting SAv for SAa (A-V mode) into Eq 2 gave a higher Rt (53.6). When SAv (A-V mode) is used, the specific activity seen by the tissues (SAa) is not considered in the calculation of Rt. Therefore, only the V-A mode meets the requirements for tracer measured metabolite turnover

The ATLAS DDM Tracer monitoring framework

International Nuclear Information System (INIS)

Zang Dongsong; Garonne, Vincent; Barisits, Martin; Lassnig, Mario; Andrew Stewart, Graeme; Molfetas, Angelos; Beermann, Thomas

2012-01-01

The DDM Tracer monitoring framework is aimed to trace and monitor the ATLAS file operations on the Worldwide LHC Computing Grid. The volume of traces has increased significantly since the framework was put in production in 2009. Now there are about 5 million trace messages every day and peaks can be near 250Hz, with peak rates continuing to climb, which gives the current structure a big challenge. Analysis of large datasets based on on-demand queries to the relational database management system (RDBMS), i.e. Oracle, can be problematic, and have a significant effect on the database's performance. Consequently, We have investigated some new high availability technologies like messaging infrastructure, specifically ActiveMQ, and key-value stores. The advantages of key value store technology are that they are distributed and have high scalability; also their write performances are usually much better than RDBMS, all of which are very useful for the Tracer monitoring framework. Indexes and distributed counters have been also tested to improve query performance and provided almost real time results. In this paper, the design principles, architecture and main characteristics of Tracer monitoring framework will be described and examples of its usage will be presented.

Simulation and interpretation of inter-well tracer tests

Directory of Open Access Journals (Sweden)

Dugstad Øyvind

2013-05-01

Full Text Available In inter-well tracer tests (IWTT, chemical compounds or radioactive isotopes are used to label injection water and gas to establish well connections and fluid patterns in petroleum reservoirs. Tracer simulation is an invaluable tool to ease the interpretation of IWTT results and is also required for assisted history matching application of tracer data. In this paper we present a new simulation technique to analyse and interpret tracer results. Laboratory results are used to establish and test formulations of the tracer conservation equations, and the technique is used to provide simulated tracer responses that are compared with observed tracer data from an extensive tracer program. The implemented tracer simulation methodology use a fast post-processing of previously simulated reservoir simulation runs. This provides a fast, flexible and powerful method for analysing gas tracer behaviour in reservoirs. We show that simulation time for tracers can be reduced by factor 100 compared to solving the tracer flow equations simultaneously with the reservoir fluid flow equations. The post-processing technique, combined with a flexible built-in local tracer-grid refinement is exploited to reduce numerical smearing, particularly severe for narrow tracer pulses.

Clinical significance of abnormal nonosseous soft tissue uptake of bone tracer

International Nuclear Information System (INIS)

Zhu Bao; Shang Yukun; Li Jiannan; Bai Jing; Cai Liang

2006-01-01

Objective: To evaluate the clinical significance of abnormal soft tissue uptake of bone tracer. Methods: Thirty patients with abnormal soft tissue uptake of bone tracer on 99 Tc m -methylene diphosphonic acid (MDP) skeletal imaging were analyzed. Radioactivity of soft tissue accumulated equal to or greater than the ribs were considered as abnormal. The result was compared with pathology, MRI, CT, X-ray, ultrasound, findings for evaluating its clinical significance. Results: In 7 patients with diffuse liver uptake of 99 Tc m -MDP, 6 were massive and 1 nodular liver cancer. In 2 patients with local liver uptake, one was metastatic and the other primary liver cancer. In 5 local lung uptake cases 4 were primary lung cancer and one metastatic. In 5 cases with colonic uptake 1 was schistosomiasis while the other 4 unexplainable. Subcutaneous tissue uptake was observed in 4 patients, symmetrical uptake in 2 patients with metastatic calcification microfoci in multiple myeloma, unsymmetrical uptake in 2 patients with hemangioma and abscess. Pleural uptake in 3 patients all was metastatic cancer. Abdominal uptake in 3 patients was omentum, paravertebral soft tissue metastasis and unknown cause. Breast uptake in one patient was due to breast cancer. Conclusions: There are many causes resulting in abnormal nonosseous soft tissue uptake of 99 Tc m -MDP. The final diagnosis should correlate with clinical data and other examinations. (authors)

Use of a variable tracer infusion method to determine glucose turnover in humans

International Nuclear Information System (INIS)

Molina, J.M.; Baron, A.D.; Edelman, S.V.; Brechtel, G.; Wallace, P.; Olefsky, J.M.

1990-01-01

The single-compartment pool fraction model, when used with the hyperinsulinemic glucose clamp technique to measure rates of glucose turnover, sometimes underestimates true rates of glucose appearance (Ra) resulting in negative values for hepatic glucose output (HGO). We focused our attention on isotope discrimination and model error as possible explanations for this underestimation. We found no difference in [3-3H] glucose specific activity in samples obtained simultaneously from the femoral artery and vein (2,400 +/- 455 vs. 2,454 +/- 522 dpm/mg) in 6 men during a hyperinsulinemic euglycemic clamp study where insulin was infused at 40 mU.m-2.min-1 for 3 h; therefore, isotope discrimination did not occur. We compared the ability of a constant (0.6 microCi/min) vs. variable tracer infusion method (tracer added to the glucose infusate) to measure non-steady-state Ra during hyperinsulinemic clamp studies. Plasma specific activity fell during the constant tracer infusion studies but did not change from base line during the variable tracer infusion studies. By maintaining a constant plasma specific activity the variable tracer infusion method eliminates uncertainty about changes in glucose pool size. This overcame modeling error and more accurately measures non-steady-state Ra (P less than 0.001 by analysis of variance vs. constant infusion method). In conclusion, underestimation of Ra determined isotopically during hyperinsulinemic clamp studies is largely due to modeling error that can be overcome by use of the variable tracer infusion method. This method allows more accurate determination of Ra and HGO under non-steady-state conditions

Cobalt and tantalum tracers measured by activation analysis in sediment transport studies

Energy Technology Data Exchange (ETDEWEB)

Groot, A.J. de [Institute for Soil Fertility, Haren (Netherlands); Allersma, E [Delft Hydraulics Laboratory, Delft (Netherlands); Bruin, M de; Houtman, J P.W. [Reactor Institute, Delft (Netherlands)

1970-09-15

The paper proposes certain principles of research to be used in investigating the origin and transport of fine-grained sediments in rivers and sea arms in connection with siltation problems of harbours and navigation channels. An element, which either does not occur in the sediment or only occurs in minute quantities, is fixed to the mud from the river or sea arm. After the material is marked it is returned to the water course where it mixes with the solids moving naturally. At specified points throughout the water course sediment samples are taken to determine the marking element by activation analysis. This gives an insight into the flow path of the suspended matter. The selection and successful application of tracers that can be measured by activation analysis depends on the sensitivity of detection, the natural occurrence of the relevant elements in the sediments under investigation and the fixation capacity of the tracer to the various grain size fractions. Further, the influence of the added element on the sedimentation behaviour of the mud in suspension and on the desorption properties must be considered. The irradiation of Co and Ta with thermal neutrons gives rise to a very sensitive evaluation of the original elements present. The fixation process of Co is restricted to sediments with special characteristics; Ta, however, can adhere tightly to any sediment. Tantalum also has the advantage that its natural content in sediments is very low. Large quantities (several per cent by weight) can adhere to the sediment without changing the sedimentation properties to an appreciable extent. Hardly any losses occur during leaching experiments simulating natural conditions. A detailed treatment is given of the chemical aspects of the method, including the behaviour of the elements used in the light of the general environmental processes of sediment constituents in deltaic systems. Finally, the scope and limits of the method are discussed. (author)

Cobalt and Tantalum Tracers Measured by Activation Analysis in Sediment Transport Studies

Energy Technology Data Exchange (ETDEWEB)

Groot, A.J. de [Institute for Soil Fertility, Haren (Netherlands); Allersma, E. [Delft Hydraulics Laboratory, Delft (Netherlands); Bruin, M. de; Houtman, J. P.W. [Reactor Institute, Delft (Netherlands)

1970-09-15

The paper proposes certain principles of research to be used in investigating the origin and transport of fine-grained sediments in rivers and sea arms in connection with siltation problems of harbours and navigation channels. An element, which either does not occur in the sediment or only occurs in minute quantities, is fixed to the mud from the river or sea arm. After the material is marked it is returned to the water course where it mixes with the solids moving naturally. At specified points throughout the water course sediment samples are taken to determine the marking element by activation analysis. This gives an insight into the flow path of the suspended matter. The selection and successful application of tracers that can be measured by activation analysis depends on the sensitivity of detection, the natural occurrence of the relevant elements in the sediments under investigation and the fixation capacity of the tracer to the various grain size fractions. Further, the influence of the added element on the sedimentation behaviour of the mud in suspension and on the desorption properties must be considered. The irradiation of Co and Ta with thermal neutrons gives rise to a very sensitive evaluation of the original elements present. The fixation process of Co is restricted to sediments with special characteristics; Ta, however, can adhere tightly to any sediment. Tantalum also has the advantage that its natural content in sediments is very low. Large quantities (several per cent by weight) can adhere to the sediment without changing the sedimentation properties to an appreciable extent. Hardly any losses occur during leaching experiments simulating natural conditions. A detailed treatment is given of the chemical aspects of the method, including the behaviour of the elements used in the light of the general environmental processes of sediment constituents in deltaic systems. Finally, the scope and limits of the method are discussed. (author)

Xanthine tracers and their preparation

International Nuclear Information System (INIS)

Groman, E.V.; Cabelli, M.D.

1980-01-01

Compounds useful as tracers in the radioimmunoassay of xanthine derivatives such as theophylline and pharmacologically related drugs are described. They are substituted xanthines in which at least one substituted radical contains radioiodine. The tracers are made by linking radioiodinatable or preradioiodinated radicals to the xanthine derivative which is to be assayed. The tracers may be employed in known radioimmunoassay techniques. (author)

Mechanisms and management of functional abdominal pain.

Science.gov (United States)

Farmer, Adam D; Aziz, Qasim

2014-09-01

Functional abdominal pain syndrome is characterised by frequent or continuous abdominal pain associated with a degree of loss of daily activity. It has a reported population prevalence of between 0.5% and 1.7%, with a female preponderance. The pathophysiology of functional abdominal pain is incompletely understood although it has been postulated that peripheral sensitisation of visceral afferents, central sensitisation of the spinal dorsal horn and aberrancies within descending modulatory systems may have an important role. The management of patients with functional abdominal pain requires a tailored multidisciplinary approach in a supportive and empathetic environment in order to develop an effective therapeutic relationship. Patient education directed towards an explanation of the pathophysiology of functional abdominal pain is in our opinion a prerequisite step and provides the rationale for the introduction of interventions. Interventions can usefully be categorised into general measures, pharmacotherapy, psychological interventions and 'step-up' treatments. Pharmacotherapeutic/step-up options include tricyclic antidepressants, serotonin noradrenergic reuptake inhibitors and the gabapentinoids. Psychological treatments include cognitive behavioural therapy and hypnotherapy. However, the objective evidence base for these interventions is largely derived from other chronic pain syndrome, and further research is warranted in adult patients with functional abdominal pain. © The Royal Society of Medicine.

Pneumatic antishock garment inflation activates the human sympathetic nervous system by abdominal compression.

Science.gov (United States)

Garvin, Nathan M; Levine, Benjamin D; Raven, Peter B; Pawelczyk, James A

2014-01-01

Pneumatic antishock garments (PASG) have been proposed to exert their blood pressure-raising effect mechanically, i.e. by increasing venous return and vascular resistance of the lower body. We tested whether, alternatively, PASG inflation activates the sympathetic nervous system. Five men and four women wore PASG while mean arterial pressure (MAP), muscle sympathetic nerve activity (MSNA), heart rate and stroke volume were measured. One leg bladder (LEG) and the abdominal bladder (ABD) of the trousers were inflated individually and in combination (ABD+LEG), at 60 or 90 mmHg for 3 min. By the end of 3 min of inflation, conditions that included the ABD region caused significant increases in MAP in a dose-dependent fashion (7 ± 2, 8 ± 3, 14 ± 4 and 13 ± 5 mmHg for ABD60, ABD+LEG60, ABD90 and ABD+LEG90, respectively, P < 0.05). Likewise, inflation that included ABD caused significant increases in total MSNA compared with control values [306 ± 70, 426 ± 98 and 247 ± 79 units for ABD60, ABD90 and ABD+LEG90, respectively, P < 0.05 (units = burst frequency × burst amplitude]. There were no changes in MAP or MSNA in the LEG-alone conditions. The ABD inflation also caused a significant decrease in stroke volume (-11 ± 3 and -10 ± 3 ml per beat in ABD90 and ABD+LEG90, respectively, P < 0.05) with no change in cardiac output. Neither cardiopulmonary receptor deactivation nor mechanical effects can account for a slowly developing rise in both sympathetic activity and blood pressure during ABD inflation. Rather, these data provide direct evidence that PASG inflation activates the sympathetic nervous system secondarily to abdominal, but not leg, compression.

Abdominal ultrasonography in the diagnostic work-up in children with recurrent abdominal pain

DEFF Research Database (Denmark)

Wewer, Anne Vibeke; Strandberg, C; Pærregaard, Anders

1997-01-01

We report on our experience with routine abdominal ultrasonography in 120 children (aged 3-15 years) with recurrent abdominal pain, in order to determine the diagnostic value of this investigation. Eight children (7%) revealed sonographic abnormalities: gallbladder stone (n = 2), splenomegaly (n...... = 1) and urogenital abnormalities (n = 5). The recurrent abdominal pain could be explained by these findings in only two (may be three) cases. CONCLUSION: The diagnostic value of abdominal ultrasonography in unselected children with recurrent abdominal pain is low. However, the direct visualization...... of the abdominal structures as being normal may be helpful to the parents and the child in their understanding and acceptance of the benign nature of recurrent abdominal pain....

Emission quantification using the tracer gas dispersion method: The influence of instrument, tracer gas species and source simulation

DEFF Research Database (Denmark)

Delre, Antonio; Mønster, Jacob; Samuelsson, Jerker

2018-01-01

The tracer gas dispersion method (TDM) is a remote sensing method used for quantifying fugitive emissions by relying on the controlled release of a tracer gas at the source, combined with concentration measurements of the tracer and target gas plumes. The TDM was tested at a wastewater treatment...... plant for plant-integrated methane emission quantification, using four analytical instruments simultaneously and four different tracer gases. Measurements performed using a combination of an analytical instrument and a tracer gas, with a high ratio between the tracer gas release rate and instrument...... precision (a high release-precision ratio), resulted in well-defined plumes with a high signal-to-noise ratio and a high methane-to-tracer gas correlation factor. Measured methane emission rates differed by up to 18% from the mean value when measurements were performed using seven different instrument...

Abdominal Muscle Activity during Mechanical Ventilation Increases Lung Injury in Severe Acute Respiratory Distress Syndrome.

Directory of Open Access Journals (Sweden)

Xianming Zhang

Full Text Available It has proved that muscle paralysis was more protective for injured lung in severe acute respiratory distress syndrome (ARDS, but the precise mechanism is not clear. The purpose of this study was to test the hypothesis that abdominal muscle activity during mechanically ventilation increases lung injury in severe ARDS.Eighteen male Beagles were studied under mechanical ventilation with anesthesia. Severe ARDS was induced by repetitive oleic acid infusion. After lung injury, Beagles were randomly assigned into spontaneous breathing group (BIPAPSB and abdominal muscle paralysis group (BIPAPAP. All groups were ventilated with BIPAP model for 8h, and the high pressure titrated to reached a tidal volume of 6ml/kg, the low pressure was set at 10 cmH2O, with I:E ratio 1:1, and respiratory rate adjusted to a PaCO2 of 35-60 mmHg. Six Beagles without ventilator support comprised the control group. Respiratory variables, end-expiratory volume (EELV and gas exchange were assessed during mechanical ventilation. The levels of Interleukin (IL-6, IL-8 in lung tissue and plasma were measured by qRT-PCR and ELISA respectively. Lung injury scores were determined at end of the experiment.For the comparable ventilator setting, as compared with BIPAPSB group, the BIPAPAP group presented higher EELV (427±47 vs. 366±38 ml and oxygenation index (293±36 vs. 226±31 mmHg, lower levels of IL-6(216.6±48.0 vs. 297.5±71.2 pg/ml and IL-8(246.8±78.2 vs. 357.5±69.3 pg/ml in plasma, and lower express levels of IL-6 mRNA (15.0±3.8 vs. 21.2±3.7 and IL-8 mRNA (18.9±6.8 vs. 29.5±7.9 in lung tissues. In addition, less lung histopathology injury were revealed in the BIPAPAP group (22.5±2.0 vs. 25.2±2.1.Abdominal muscle activity during mechanically ventilation is one of the injurious factors in severe ARDS, so abdominal muscle paralysis might be an effective strategy to minimize ventilator-induce lung injury.

Abdominal Muscle Activity during Mechanical Ventilation Increases Lung Injury in Severe Acute Respiratory Distress Syndrome.

Science.gov (United States)

Zhang, Xianming; Wu, Weiliang; Zhu, Yongcheng; Jiang, Ying; Du, Juan; Chen, Rongchang

2016-01-01

It has proved that muscle paralysis was more protective for injured lung in severe acute respiratory distress syndrome (ARDS), but the precise mechanism is not clear. The purpose of this study was to test the hypothesis that abdominal muscle activity during mechanically ventilation increases lung injury in severe ARDS. Eighteen male Beagles were studied under mechanical ventilation with anesthesia. Severe ARDS was induced by repetitive oleic acid infusion. After lung injury, Beagles were randomly assigned into spontaneous breathing group (BIPAPSB) and abdominal muscle paralysis group (BIPAPAP). All groups were ventilated with BIPAP model for 8h, and the high pressure titrated to reached a tidal volume of 6ml/kg, the low pressure was set at 10 cmH2O, with I:E ratio 1:1, and respiratory rate adjusted to a PaCO2 of 35-60 mmHg. Six Beagles without ventilator support comprised the control group. Respiratory variables, end-expiratory volume (EELV) and gas exchange were assessed during mechanical ventilation. The levels of Interleukin (IL)-6, IL-8 in lung tissue and plasma were measured by qRT-PCR and ELISA respectively. Lung injury scores were determined at end of the experiment. For the comparable ventilator setting, as compared with BIPAPSB group, the BIPAPAP group presented higher EELV (427±47 vs. 366±38 ml) and oxygenation index (293±36 vs. 226±31 mmHg), lower levels of IL-6(216.6±48.0 vs. 297.5±71.2 pg/ml) and IL-8(246.8±78.2 vs. 357.5±69.3 pg/ml) in plasma, and lower express levels of IL-6 mRNA (15.0±3.8 vs. 21.2±3.7) and IL-8 mRNA (18.9±6.8 vs. 29.5±7.9) in lung tissues. In addition, less lung histopathology injury were revealed in the BIPAPAP group (22.5±2.0 vs. 25.2±2.1). Abdominal muscle activity during mechanically ventilation is one of the injurious factors in severe ARDS, so abdominal muscle paralysis might be an effective strategy to minimize ventilator-induce lung injury.

Longitudinal changes in abdominal fat distribution with menopause.

Science.gov (United States)

Franklin, Ruth M; Ploutz-Snyder, Lori; Kanaley, Jill A

2009-03-01

Increases in abdominal fat have been reported with menopause, but the impact of menopause on abdominal fat distribution (visceral vs subcutaneous) is still unclear. The objective of the study was to determine if abdominal fat content (volume) or distribution is altered with menopause. Magnetic resonance imaging was used to quantify total abdominal, subcutaneous, and visceral fat in 8 healthy women, both in the premenopausal state and 8 years later in the postmenopausal state. Physical activity (PA) and blood lipids were also measured. Body weight and waist circumference did not change with menopause (pre- vs postmenopause: body weight, 63.2 +/- 3.1 vs 63.9 +/- 2.5 kg; waist circumference, 92.1 +/- 4.6 vs 93.4 +/- 3.7 cm); however, total abdominal fat, subcutaneous fat, and visceral fat all significantly (P fat distribution was not significantly different after menopause (pre- vs postmenopause: subcutaneous, 73% +/- 3% vs 71% +/- 3%; visceral, 26% +/- 3% vs 28% +/- 3%). Lean mass, fat mass, and PA, along with total cholesterol and triglyceride levels, did not change with menopause. High-density lipoprotein and low-density lipoprotein both increased (P abdominal fat content increased with menopause despite no change in PA, body weight, or waist circumference; however, menopause did not affect the relative abdominal fat distribution in these women.

Abdominal fat sub-depots and energy expenditure: Magnetic resonance imaging study.

Science.gov (United States)

Serfaty, Dana; Rein, Michal; Schwarzfuchs, Dan; Shelef, Ilan; Gepner, Yftach; Bril, Nitzan; Cohen, Noa; Shemesh, Elad; Sarusi, Benjamin; Kovsan, Julia; Kenigsbuch, Shira; Chassidim, Yoash; Golan, Rachel; Witkow, Shula; Henkin, Yaakov; Stampfer, Meir J; Rudich, Assaf; Shai, Iris

2017-06-01

We aimed to assess the association between the distinct abdominal sub-depots and resting energy expenditure (REE). We performed magnetic resonance imaging (MRI) to quantify abdominal visceral-adipose-tissue (VAT), deep-subcutaneous-adipose-tissue (deep-SAT), and superficial-subcutaneous-adipose-tissue (superficial-SAT). We measured REE by indirect-calorimetry. Non-exercise activity thermogenesis (NEAT) [1-3 metabolic equivalents (METs)] and exercise thermogenesis (activities of 4+MET S ) were estimated based on 6-days of accelerometry to assess total physical activity energy expenditure (PAEE). We studied 282 participants: 249 men [mean age = 47.4 years, body-mass-index (BMI) = 31 kg/m 2 , mean VAT proportion from total abdominal fat = 34.5%, mean superficial-SAT proportion from total abdominal fat = 24.3%] and 33 women (mean age = 51.2 years, BMI = 30.1 kg/m 2 , mean VAT proportion from total abdominal fat = 22.8%, mean superficial-SAT proportion from total abdominal fat = 37.8%). As expected, women had lower REE [by 32.4% (1488 ± 234 kcal/day vs. 1971 ± 257 kcal/day; p abdominal VAT was the dominant proportional depot, had higher REE (1964 ± 297 kcal/day vs. 1654 ± 352 kcal/day; p Abdominal fat distribution patterns are associated with varying levels of resting energy expenditure, potentially reflecting different metabolic rates of adipose sub-depots and providing an anatomic/anthropometric link to physiological obese sub-phenotypes. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Diurnal and seasonal variation in air exchange rates and interzonal flows measured by active tracer gas in five Danish homes

DEFF Research Database (Denmark)

Clausen, Geo; Bekö, Gabriel; Toftum, Jørn

2016-01-01

We measured the air exchange rates (AER) in up to six rooms in five naturally ventilated dwellings across four seasons using active tracer gas. Night time AER was also estimated in all bedrooms based on occupant-generated CO2. Additionally, we studied the pollutant distribution across the dwellin...

The value of plain abdominal radiographs in management of abdominal emergencies in Luth.

Science.gov (United States)

Ashindoitiang, J A; Atoyebi, A O; Arogundade, R A

2008-01-01

The plain abdominal x-ray is still the first imaging modality in diagnosis of acute abdomen. The aim of this study was to find the value of plain abdominal x-ray in the management of abdominal emergencies seen in Lagos university teaching hospital. The accurate diagnosis of the cause of acute abdominal pain is one of the most challenging undertakings in emergency medicine. This is due to overlapping of clinical presentation and non-specific findings of physical and even laboratory data of the multifarious causes. Plain abdominal radiography is one investigation that can be obtained readily and within a short period of time to help the physician arrive at a correct diagnosis The relevance of plain abdominal radiography was therefore evaluated in the management of abdominal emergencies seen in Lagos over a 12 month period (April 2002 to March 2003). A prospective study of 100 consecutively presenting patients with acute abdominal conditions treated by the general surgical unit of Lagos University Teaching Hospital was undertaken. All patients had supine and erect abdominal x-ray before any therapeutic intervention was undertaken. The diagnostic features of the plain films were compared with final diagnosis to determine the usefulness of the plain x-ray There were 54 males and 46 females (M:F 1.2:1). Twenty-four percent of the patients had intestinal obstruction, 20% perforated typhoid enteritis; gunshot injuries and generalized peritonitis each occurred in 13%, blunt abdominal trauma in 12%, while 8% and 10% had acute appendicitis and perforated peptic ulcer disease respectively. Of 100 patients studied, 54% had plain abdominal radiographs that showed positive diagnostic features. Plain abdominal radiograph showed high sensitivity in patients with intestinal obstruction 100% and perforated peptic ulcer 90% but was less sensitive in patients with perforated typhoid, acute appendicitis, and blunt abdominal trauma and generalized peritonitis. In conclusion, this study

Evaluation of the levels of metalloproteinsase-2 in patients with abdominal aneurysm and abdominal hernias.

Science.gov (United States)

Antoszewska, Magdalena

2013-05-01

Abdominal aortic aneurysms and abdominal hernias become an important health problems of our times. Abdominal aortic aneurysm and its rupture is one of the most dangerous fact in vascular surgery. There are some theories pointing to a multifactoral genesis of these kinds of diseases, all of them assume the attenuation of abdominal fascia and abdominal aortic wall. The density and continuity of these structures depend on collagen and elastic fibers structure. Reducing the strength of the fibers may be due to changes in the extracellular matrix (ECM) by the proteolytic enzymes-matrix metalloproteinases (MMPs) that degrade extracellular matrix proteins. These enzymes play an important role in the development of many disease: malignant tumors (colon, breast, lung, pancreas), cardiovascular disease (myocardial infarction, ischemia-reperfusion injury), connective tissue diseases (Ehler-Danlos Syndrome, Marfan's Syndrome), complications of diabetes (retinopathy, nephropathy). One of the most important is matrix metalloproteinase-2 (MMP-2). The aim of the study was an estimation of the MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia, and in patients with only abdominal aortic aneurysm. The study involved 88 patients aged 42 to 89 years, including 75 men and 13 women. Patients were divided into two groups: patients with abdominal aortic aneurysm and primary abdominal hernia (45 persons, representing 51.1% of all group) and patients with only abdominal aortic aneurysm (43 persons, representing 48,9% of all group). It was a statistically significant increase in MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia compared to patients with only abdominal aortic aneurysm. It was a statistically significant increase in the prevalence of POCHP in patients with only abdominal aortic aneurysm compared to patients with abdominal aortic aneurysm and primary abdominal hernia. Statistically significant

Isotopic marking and tracers

International Nuclear Information System (INIS)

Morel, F.

1997-01-01

The use of radioactive isotopes as tracers in biology has been developed thanks to the economic generation of the required isotopes in accelerators and nuclear reactors, and to the multiple applications of tracers in the life domain; the most usual isotopes employed in biology are carbon, hydrogen, phosphorus and sulfur isotopes, because these elements are present in most of organic molecules. Most of the life science knowledge appears to be dependent to the extensive use of nuclear tools and radioactive tracers; the example of the utilization of radioactive phosphorus marked ATP to study the multiple reactions with proteins, nucleic acids, etc., is given

Radiation dose estimates for carbon-11-labelled PET tracers

International Nuclear Information System (INIS)

Aart, Jasper van der; Hallett, William A.; Rabiner, Eugenii A.; Passchier, Jan; Comley, Robert A.

2012-01-01

Introduction: Carbon-11-labelled positron emission tomography (PET) tracers commonly used in biomedical research expose subjects to ionising radiation. Dosimetry is the measurement of radiation dose, but also commonly refers to the estimation of health risk associated with ionising radiation. This review describes radiation dosimetry of carbon-11-labelled molecules in the context of current PET research and the most widely used regulatory guidelines. Methods: A MEDLINE literature search returned 42 articles; 32 of these were based on human PET data dealing with radiation dosimetry of carbon-11 molecules. Radiation burden expressed as effective dose and maximum absorbed organ dose was compared between tracers. Results: All but one of the carbon-11-labelled PET tracers have an effective dose under 9 μSv/MBq, with a mean of 5.9 μSv/MBq. Data show that serial PET scans in a single subject are feasible for the majority of radiotracers. Conclusion: Although differing in approach, the two most widely used regulatory frameworks (those in the USA and the EU) do not differ substantially with regard to the maximum allowable injected activity per PET study. The predictive validity of animal dosimetry models is critically discussed in relation to human dosimetry. Finally, empirical PET data are related to human dose estimates based on homogenous distribution, generic models and maximum cumulated activities. Despite the contribution of these models to general risk estimation, human dosimetry studies are recommended where continued use of a new PET tracer is foreseen.

Measurement of open streams by using tracers

International Nuclear Information System (INIS)

Ramos, German F.; Tarquino, W.; Curcuy, H.; Orozco, C.

1999-01-01

This paper presents an intercomparison study to be carried out between flux measurements by using tracers and moulinet. This intercomparison is scheduled to be performed at the measurement station belonging to the National Service of Meteorology and Hydrology (SENAMHI). Two techniques of tracer dilution are outstanded: total evaluation with tracer punctual injection and punctual evaluation with tracer continuous injection. Total evaluation with tracer punctual injection has been used since this technique is considered to be more suitable for hydrology purposes

Guidebook on radioisotope tracers in industry

International Nuclear Information System (INIS)

1990-01-01

The idea of using tracers (chemical, dyes, etc.) in the investigation of complex physical phenomena has always attracted the attention of scientists and engineers. When radioactive isotopes became available it was immediately recognized that they offered an almost ideal solution to tracer selection. This book is devoted to reviewing the present status of the tracer method as such and to its applications to those branches of industry which have derived large benefits from the use of this modern technology. The main objectives of the IAEA's Industrial Applications and Chemistry Section is to help Member States in introducing to their own industries the different isotope and radiation techniques which have become available as a result of developments in the nuclear sciences. This section proposed the preparation of this guidebook, putting together various radiotracer methods and the experience obtained so far in their industrial use. Chapters 2 to 4 cover the general concept of tracers, technology and safety aspects, as well as data evaluation and interpretation. In chapter 5, therefore, general applications are discussed. In chapter 6, specialists in selected fields discuss their experience in radiotracer applications in various types of industrial activity. Most case studies are illustrated by at least one detailed example of an experiment carried out at an industrial installation. Current trends in the development of radiotracer methods are discussed in chapter 7, from both a theoretical and a practical viewpoint. Some possible new RTT applications in the future are also discussed here. Sealed radioactive sources are used almost as often as radioisotope tracers in industrial measurements. Annex I gives a short review of these techniques. Readers who are interested in the basic principles of radioisotope production will find the necessary information in Annex II. Annexes III, V and VI provide a demonstration of fundamental relations and properties; useful

Tracer attenuation in groundwater

Science.gov (United States)

Cvetkovic, Vladimir

2011-12-01

The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

Focused abdominal sonography for trauma (FAST) in blunt paediatric abdominal trauma

International Nuclear Information System (INIS)

Faruque, A. V.; Qazi, S. H.; Khan, M. A. M.

2013-01-01

Objective: To evaluate the role of focussed abdominal sonography for trauma in blunt paediatric abdominal trauma patients, and to see if the role of computed tomography scan could be limited to only those cases in which sonography was positive. Methods: The retrospective study covered 10 years, from January 1, 2000 to December 31, 2009, and was conducted at the Department of Radiology and Department of Emergency Medicine, Aga Khan University Hospital, Karachi. It comprised cases of 174 children from birth to 14 years who had presented with blunt abdominal trauma and had focussed abdominal sonography for trauma done at the hospital. The findings were correlated with computed tomography scan of the abdomen and clinical follow-up. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of focussed abdominal sonography for trauma were calculated for blunt abdominal trauma. SPSS 17 was used for statistical analysis. Results: Of the total 174 cases, 31 (17.81%) were later confirmed by abdominal scan. Of these 31 children, sonography had been positive in 29 (93.54%) children. In 21 (67.74%) of the 31 children, sonography had been true positive; 8 (25%) (8/31) were false positive; and 2 (6%) (2/31) were false negative. There were 6 (19.3%) children in which sonography was positive and converted to laparotomy. There was no significant difference on account of gender (p>0.356). Focussed abdominal sonography for trauma in the study had sensitivity of 91%, specificity of 95%, positive predictive value of 73%, and negative predictive value of 73% with accuracy of 94%. All patients who had negative sonography were discharged later, and had no complication on clinical follow-up. Conclusions: Focussed abdominal sonography for trauma is a fairly reliable mode to assess blunt abdominal trauma in children. It is a useful tool to pick high-grade solid and hollow viscous injury. The results suggest that the role of computed tomography scan can be

Focused abdominal sonography for trauma (FAST) in blunt paediatric abdominal trauma.

Science.gov (United States)

Faruque, Ahmad Vaqas; Qazi, Saqib Hamid; Khan, Muhammad Arif Mateen; Akhtar, Wassem; Majeed, Amina

2013-03-01

To evaluate the role of focussed abdominal sonography for trauma in blunt paediatric abdominal trauma patients, and to see if the role of computed tomography scan could be limited to only those cases in which sonography was positive. The retrospective study covered 10 years, from January 1,2000 to December 31,2009, and was conducted at the Department of Radiology and Department of Emergency Medicine, Aga Khan University Hospital, Karachi. It comprised cases of 174 children from birth to 14 years who had presented with blunt abdominal trauma and had focussed abdominal sonography for trauma done at the hospital. The findings were correlated with computed tomography scan of the abdomen and clinical follow-up. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of focussed abdominal sonography for trauma were calculated for blunt abdominal trauma. SPSS 17 was used for statistical analysis. Of the total 174 cases, 31 (17.81%) were later confirmed by abdominal scan. Of these 31 children, sonography had been positive in 29 (93.54%) children. In 21 (67.74%) of the 31 children, sonograpy had been true positive; 8 (25%) (8/31) were false positive; and 2 (6%) (2/31) were false negative. There were 6 (19.3%) children in which sonography was positive and converted to laparotomy. There was no significant difference on account of gender (p>0.356). Focussed abdominal sonography for trauma in the study had sensitivity of 91%, specificity of 95%, positive predictive value of 73%, and negative predictive value of 73% with accuracy of 94%. All patients who had negative sonography were discharged later, and had no complication on clinical follow-up. Focussed abdominal sonography for trauma is a fairly reliable mode to assess blunt abdominal trauma in children. It is a useful tool to pick high-grade solid and hollow viscous injury. The results suggest that the role of computed tomography scan can be limited to those cases in which focussed

Obesity-Associated Abdominal Elephantiasis

Directory of Open Access Journals (Sweden)

Ritesh Kohli

2013-01-01

Full Text Available Abdominal elephantiasis is a rare entity. Abdominal elephantiasis is an uncommon, but deformative and progressive cutaneous disease caused by chronic lymphedema and recurrent streptococcal or Staphylococcus infections of the abdominal wall. We present 3 cases of patients with morbid obesity who presented to our hospital with abdominal wall swelling, thickening, erythema, and pain. The abdominal wall and legs were edematous, with cobblestone-like, thickened, hyperpigmented, and fissured plaques on the abdomen. Two patients had localised areas of skin erythema, tenderness, and increased warmth. There was purulent drainage from the abdominal wall in one patient. They were managed with antibiotics with some initial improvement. Meticulous skin care and local keratolytic treatment for the lesions were initiated with limited success due to their late presentation. All three patients refused surgical therapy. Conclusion. Early diagnosis is important for the treatment of abdominal elephantiasis and prevention of complications.

Coefficients of tracer transfer through membranes. Pt. 7

Energy Technology Data Exchange (ETDEWEB)

Dorabialska, A; Hawlicka, E; Plonka, A [Politechnika Lodzka (Poland)

1974-01-01

The doubled value of the tracer transfer coefficient in the self-diffusion process is equal to the sum of tracer transfer coefficients in the diffusion and interfusion processes. The fundamental phenomenological relation can be deduced for the coefficients of tracer transfer between two phases of electrolyte solutions spearated by a virtual boundary. Indeed, the doubled value of the tracer mobility in the self-diffusion experiment (no concentration gradient of the traced substance) is equal to the sum of the tracer mobilities in the diffusion (tracer movement along with the concentration gradient of the traced substance) and interfusion experiments (tracer movement against the concentration gradient of the traced substance). Thus the doubled value of the tracer transfer coefficient in the self-diffusion process should be equal to the sum of tracer transfer coefficients in the diffusion and interfusion processes. The experimental verification of that fundamental relation is presented.

Child with Abdominal Pain.

Science.gov (United States)

Iyer, Rajalakshmi; Nallasamy, Karthi

2018-01-01

Abdominal pain is one of the common symptoms reported by children in urgent care clinics. While most children tend to have self-limiting conditions, the treating pediatrician should watch out for underlying serious causes like intestinal obstruction and perforation peritonitis, which require immediate referral to an emergency department (ED). Abdominal pain may be secondary to surgical or non-surgical causes, and will differ as per the age of the child. The common etiologies for abdominal pain presenting to an urgent care clinic are acute gastro-enteritis, constipation and functional abdominal pain; however, a variety of extra-abdominal conditions may also present as abdominal pain. Meticulous history taking and physical examination are the best tools for diagnosis, while investigations have a limited role in treating benign etiologies.

Long residence times - bad tracer tests?

Science.gov (United States)

Ghergut, Julia; Behrens, Horst; Sauter, Martin

2015-04-01

Tracer tests conducted at geothermal well doublets or triplets in the Upper Rhine Rift Valley [1] all face, with very few exceptions so far, one common issue: lack of conclusive tracer test results, or tracer signals still undetectable for longer than one or two years after tracer injection. While the reasons for this surely differ from site to site (Riehen, Landau, Insheim, Bruchsal, ...), its effects on how the usefulness of tracer tests is perceived by the non-tracer community are pretty much the same. The 'poor-signal' frustration keeps nourishing two major 'alternative' endeavours : (I) design and execute tracer tests in single-well injection-withdrawal (push-pull), 'instead of' inter-well flow-path tracing configurations; (II) use 'novel' tracer substances instead of the 'old' ones which have 'obviously failed'. Frustration experienced with most inter-well tracer tests in the Upper Rhine Rift Valley has also made them be regarded as 'maybe useful for EGS' ('enhanced', or 'engineered' geothermal systems, whose fluid RTD typically include a major share of values below one year), but 'no longer worthwhile a follow-up sampling' in natural, large-scale hydrothermal reservoirs. We illustrate some of these arguments with the ongoing Bruchsal case [2]. The inter-well tracer test conducted at Bruchsal was (and still is!) aimed at assessing inter-well connectivity, fluid residence times, and characterizing the reservoir structure [3]. Fluid samples taken at the geothermal production well after reaching a fluid turnover of about 700,000 m3 showed tracer concentrations in the range of 10-8 Minj per m3, in the liquid phase of each sample (Minj being the total quantity of tracer injected as a short pulse at the geothermal re-injection well). Tracer signals might actually be higher, owing to tracer amounts co-precipitated and/or adsorbed onto the solid phase whose accumulation in the samples was unavoidable (due to pressure relief and degassing during the very sampling

Wairakei tracer tests 1983

International Nuclear Information System (INIS)

McCabe, W.J.; Barry, B.J.

1984-05-01

Tracer tests, with and without, hot water reinjection into WK213 showed returns of tracer iodine-131; in wells in both the Waiora Valley and the eastern end of the field. The effect of reinjection at a rate of 200 cu. m/h was to reduce the arrived time from 15 to 7 days. Increasing the rate of reinjection into WK62 from 30 cu. m/h to 200 cu. m/h seemed to increase the initial velocity of the tracer wave and the distance it moved. However, returns were recorded only in the adjacent wells WK61 and WK63 with a very small, and three days delayed, response in WK43

[Project to improve abdominal obesity in day care ward psychiatric patients].

Science.gov (United States)

Liu, Yu-Chieh; Wang, Hui-Yu; Huang, Hui-Ling; Chen, Min-Li

2011-06-01

Over half (57.14%) of patients in our ward suffer from abdominal obesity. This rate is on a continuing upward trend. Reasons for such obesity include lack of physical activity classes, inadequate physical activity, high calorie diets and unhealthy eating habits, chronic diseases and drug side effects, poor motivation to reduce weight, and lack of crisis awareness of abdominal obesity. This project was designed to lessen the problem of abdominal obesity among psychiatric day care inpatients. Resolution measures implemented included: (1) arranging aerobic exercise classes; (2) scheduling classes to teach patients healthy diet habits and knowledge regarding diseases and drugs; (3) holding a waistline reduction competition; (4) displaying health education bulletin boards; (5) holding a quiz contest with prizes for correct answers. The eight abdominally obese patients in the ward achieved an average waist circumference reduction of 2.9 cm and the overall abdominal obesity rate in the ward fell to 35.7%. BMI, eating habits, and awareness of weight loss importance and motivation all improved. The outcome achieved targeted project objectives. We recommend the integration of obesity prevention into routine ward activities and quality control indicators. Nurses should provide patients with weight loss concepts, regularly monitor risk factors, and encourage patient family cooperation to maintain medical care quality.

Investigation by tracer method of water balance in filling the gob with slurries

International Nuclear Information System (INIS)

Jureczko, J.; Skowronek, E.

1977-01-01

Results of investigations on the establishment of conditions of water flow in filling old workings with mud, in order to determine the degree of water hazard for mine workings in one of mines are given. For the inspection of flow, the stable tracer method and the neutron activation analysis were used. Chromium as a complex compound with EDTA was used as tracer. Geological and mining conditions in the area of investigations by tracers are given and the disposal of diluted stowing slurry is characterized. The method of interpretation of results is discussed in order to determine the water flow rate in the gob and to draw up the water balance on the basis of the curve of tracer travel. (author)

Abdominal Compartment Syndrome

Directory of Open Access Journals (Sweden)

Pınar Zeyneloğlu

2015-04-01

Full Text Available Intraabdominal hypertension and Abdominal compartment syndrome are causes of morbidity and mortality in critical care patients. Timely diagnosis and treatment may improve organ functions. Intra-abdominal pressure monitoring is vital during evaluation of the patients and in the management algorithms. The incidence, definition and risk factors, clinical presentation, diagnosis and management of intraabdominal hypertension and Abdominal compartment syndrome were reviewed here.

Abdominal wall fat pad biopsy

Science.gov (United States)

Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... is the most common method of taking an abdominal wall fat pad biopsy . The health care provider cleans the ...

Effects of hippotherapy on the thickness of deep abdominal muscles and activity of daily living in children with intellectual disabilities.

Science.gov (United States)

Lee, JiHyun; Yun, Chang-Kyo

2017-04-01

[Purpose] The purpose of this study is to investigate the effect of hippotherapy exercise on the thickness of deep abdominal muscles and daily activities of children with intellectual disabilities. [Subjects and Methods] Seven children with intellectual disabilities were treated with hippotherapy for 30 minutes twice a week for 6 weeks. The thickness of deep abdominal muscles and Functional Independence Measure (FIM) of the subjects were measured by ultrasonography before and after the experiment. [Results] There was no significant change in the thickness of the External Oblique and Internal Oblique muscles, but there was a statistically significant change in Transverse Adbominis thickness and FIM score after treatment compared to before treatment. [Conclusion] Hippotherapy exercise has a positive effect on the improvement of Transverse Abdominis (TrA) and activity of daily livings of children with intellectual disabilities.

Natural tracer profiles across argillaceous formations

International Nuclear Information System (INIS)

Mazurek, Martin; Alt-Epping, Peter; Bath, Adrian; Gimmi, Thomas; Niklaus Waber, H.; Buschaert, Stephane; Canniere, Pierre De; Craen, Mieke De; Gautschi, Andreas; Savoye, Sebastien; Vinsot, Agnes; Wemaere, Isabelle; Wouters, Laurent

2011-01-01

shapes of the profiles can be explained by diffusion acting as the dominant transport process over periods of several thousands to several millions of years and at the length scales of the profiles. Transport by advection has a negligible influence on the observed profiles at most sites, as can be shown by estimating the maximum advection velocities that still give acceptable fits of the model with the data. The advantages and disadvantages of different conservative tracers are also assessed. The anion Cl - is well suited as a natural tracer in aquitards, because its concentration varies considerably in environmental waters. It can easily be measured, although the uncertainty regarding the fraction of the pore space that is accessible to anions in clays remains an issue. The stable water isotopes are also well suited, but they are more difficult to measure and their values generally exhibit a smaller relative range of variation. Chlorine isotopes (δ 37 Cl) and He are more difficult to interpret because initial and boundary conditions cannot easily be constrained by independent evidence. It is also shown that the existence of perturbing events such as the activation of aquifers due to uplift and erosion, leading to relatively sharp changes of boundary conditions, can be considered as a pre-requisite to obtain well-interpretable tracer signatures. On the other hand, gradual changes of boundary conditions are more difficult to parameterise and so may preclude a clear interpretation.

Tracer research in process engineering

International Nuclear Information System (INIS)

Iller, E.

1992-01-01

The book is a review of modern applications of tracer techniques in chemical and process engineering studies. The next topics have been extensively presented: 1) media flow through apparatus; 2) the tracers in the study of media flow dynamics through apparatus; 3) mathematical interpretation of experimental data from impulse-response method; 4) the models of media flow through chemical reactors and apparatus; 5) radiotracers in mass transport study; 6) examples of practical applications of tracer methods in industrial objects. 84 refs, 96 figs, 31 tabs

Meteorological tracers in regional planning

International Nuclear Information System (INIS)

Mueller, K.H.

1974-11-01

Atmospheric tracers can be used as indicators to study both the ventilation of an urban region and its dispersion meteorology for air pollutants. A correlation analysis applied to the space-time dependent tracer concentrations is able to give transfer functions, the structure and characteristic parameters of which describe the meteorological and topographical situation of the urban region and its surroundings in an integral manner. To reduce the number of persons usually involved in a tracer experiment an automatic air sampling system had to be developed

Accuracy of the abdominal examination for identifying children with blunt intra-abdominal injuries.

Science.gov (United States)

Adelgais, Kathleen M; Kuppermann, Nathan; Kooistra, Joshua; Garcia, Madelyn; Monroe, David J; Mahajan, Prashant; Menaker, Jay; Ehrlich, Peter; Atabaki, Shireen; Page, Kent; Kwok, Maria; Holmes, James F

2014-12-01

To determine the accuracy of complaints of abdominal pain and findings of abdominal tenderness for identifying children with intra-abdominal injury (IAI) stratified by Glasgow Coma Scale (GCS) score. This was a prospective, multicenter observational study of children with blunt torso trauma and a GCS score ≥13. We calculated the sensitivity of abdominal findings for IAI with 95% CI stratified by GCS score. We examined the association of isolated abdominal pain or tenderness with IAI and that undergoing acute intervention (therapeutic laparotomy, angiographic embolization, blood transfusion, or ≥2 nights of intravenous fluid therapy). Among the 12 044 patients evaluated, 11 277 (94%) had a GCS score of ≥13 and were included in this analysis. Sensitivity of abdominal pain for IAI was 79% (95% CI, 76%-83%) for patients with a GCS score of 15, 51% (95% CI, 37%-65%) for patients with a GCS score of 14, and 32% (95% CI, 14%-55%) for patients with a GCS score of 13. Sensitivity of abdominal tenderness for IAI also decreased with decreasing GCS score: 79% (95% CI, 75%-82%) for a GCS score of 15, 57% (95% CI, 42%-70%) for a GCS score of 14, and 37% (95% CI, 19%-58%) for a GCS score of 13. Among patients with isolated abdominal pain and/or tenderness, the rate of IAI was 8% (95% CI, 6%-9%) and the rate of IAI undergoing acute intervention was 1% (95% CI, 1%-2%). The sensitivity of abdominal findings for IAI decreases as GCS score decreases. Although abdominal computed tomography is not mandatory, the risk of IAI is sufficiently high that diagnostic evaluation is warranted in children with isolated abdominal pain or tenderness. Copyright © 2014 Elsevier Inc. All rights reserved.

New SPECT tracers: Example of tracers of proteoglycans and melanin

International Nuclear Information System (INIS)

Cachin, F.; Mestas, D.; Kelly, A.; Merlin, C.; Veyre, A.; Maublant, J.; Cachin, F.; Chezal, J.M.; Miot-Noirault, E.; Moins, N.; Auzeloux, P.; Vidal, A.; Bonnet-Duquennoy, M.; Boisgard, S.; D'Incan, M.; Madelmont, J.C.; Maublant, J.; Boisgard, S.; D'Incan, M.; Redini, F.; Filaire, M.

2009-01-01

The majority of research program on new radiopharmaceuticals turn to tracers used for positron emission tomography (PET). Only a few teams work on new non fluorine labeled tracers. However, the coming of SPECT/CT gamma cameras, the arrival of semi-conductors gamma cameras should boost the development of non-PET tracers. We exhibit in this article the experience acquired by our laboratory in the conception and design of two new non fluorine labelled compounds. The 99m Tc-N.T.P. 15-5 (N.T.P. 15-5 for N-[tri-ethyl-ammonium]-3-propyl-[15]ane-N5) which binds to proteoglycans could be used for the diagnosis and staging of osteoarthritis and chondrosarcoma. The iodo benzamides, specific to the melanin, are nowadays compared to 18 F-fluorodeoxyglucose in a phase III clinical trial for the diagnosis and detection of melanoma metastasis. Our last development focus on N-[2-(diethyl-amino)ethyl]-4 and 2-iodo benzamides respectively B.Z.A. and B.Z.A.2 hetero-aromatic analogues usable for melanoma treatment. (authors)

Internal Mammary Vessels’ Impact on Abdominal Skin Perfusion in Free Abdominal Flap Breast Reconstruction

Directory of Open Access Journals (Sweden)

Solveig Nergård, MD

2017-12-01

Conclusions:. Using the IMV in free abdominal flap breast reconstruction had a significant effect on abdominal skin perfusion and may contribute to abdominal wound healing problems. The reperfusion of the abdominal skin was a dynamic process showing an increase in perfusion in the affected areas during the postoperative days.

Tc-99m sulfur colloid scanning in blunt trauma: detection of abdominal bleeding

International Nuclear Information System (INIS)

Bronfman, H.J.; Kunkel, B.K.; Rabin, H.S.

1981-01-01

Tc-99m sulfur colloid scintigraphy can detect and locate active lower gastrointestinal bleeding. The same principles apply to the detection and location of active intra-abdominal or pelvic hemorrhage following blunt abdominal trauma. We report two patients with abdominal bleeding who were correctly diagnosed by this method. As part of the routine examination of all patients having Tc-99m sulfur colloid liver-spleen scans for trauma, 500,000-count images should be made of the rest of the abdomen and pelvis

Compilation and analyses of results from cross-hole tracer tests with conservative tracers

Energy Technology Data Exchange (ETDEWEB)

Hjerne, Calle; Nordqvist, Rune; Harrstroem, Johan (Geosigma AB (Sweden))

2010-09-15

Radionuclide transport in hydrogeological formations is one of the key factors for the safety analysis of a future repository of nuclear waste. Tracer tests have therefore been an important field method within the SKB investigation programmes at several sites since the late 1970's. This report presents a compilation and analyses of results from cross-hole tracer tests with conservative tracers performed within various SKB investigations. The objectives of the study are to facilitate, improve and reduce uncertainties in predictive tracer modelling and to provide supporting information for SKB's safety assessment of a final repository of nuclear waste. More specifically, the focus of the report is the relationship between the tracer mean residence time and fracture hydraulic parameters, i.e. the relationship between mass balance aperture and fracture transmissivity, hydraulic diffusivity and apparent storativity. For 74 different combinations of pumping and injection section at six different test sites (Studsvik, Stripa, Finnsjoen, Aespoe, Forsmark, Laxemar), estimates of mass balance aperture from cross-hole tracer tests as well as transmissivity were extracted from reports or in the SKB database Sicada. For 28 of these combinations of pumping and injection section, estimates of hydraulic diffusivity and apparent storativity from hydraulic interference tests were also found. An empirical relationship between mass balance aperture and transmissivity was estimated, although some uncertainties for individual data exist. The empirical relationship between mass balance aperture and transmissivity presented in this study deviates considerably from other previously suggested relationships, such as the cubic law and transport aperture as suggested by /Dershowitz and Klise 2002/, /Dershowitz et al. 2002/ and /Dershowitz et al. 2003/, which also is discussed in this report. No clear and direct empirical relationship between mass balance aperture and hydraulic

Tracer filamentation at an unstable ocean front

Science.gov (United States)

Feng, Yen Chia; Mahadevan, Amala; Thiffeault, Jean-Luc; Yecko, Philip

2017-11-01

A front, where two bodies of ocean water with different physical properties meet, can become unstable and lead to a flow with high strain rate and vorticity. Phytoplankton and other oceanic tracers are stirred into filaments by such flow fields, as can often be seen in satellite imagery. The stretching and folding of a tracer by a two-dimensional flow field has been well studied. In the ocean, however, the vertical shear of horizontal velocity is typically two orders of magnitude larger than the horizontal velocity gradient. Theoretical calculations show that vertical shear alters the way in which horizontal strain affects the tracer, resulting in thin, sloping structures in the tracer field. Using a non-hydrostatic ocean model of an unstable ocean front, we simulate tracer filamentation to identify the effect of vertical shear on the deformation of the tracer. In a complementary laboratory experiment, we generate a simple, vertically sheared strain flow and use dye and particle image velocimetry to quantify the filamentary structures in terms of the strain and shear. We identify how vertical shear alters the tracer filaments and infer how the evolution of tracers in the ocean will differ from the idealized two-dimensional paradigm. Support of NSF DMS-1418956 is acknowledged.

Tracer dispersion - experiment and CFD

International Nuclear Information System (INIS)

Zitny, R.

2004-01-01

Description of tracer distribution by means of dispersion models is a method successfully used in process engineering for fifty years. Application of dispersion models in reactor engineering for characterization of flows in column apparatus, heat exchangers, etc. is summarized and experimental tracer techniques as well as CFD methods for dispersion coefficients evaluation are discussed. Possible extensions of thermal axial dispersion model (ADM) and a core-wall ADM model suitable for description of tracer dispersion in laminar flows are suggested as well as CFD implementation as 1D finite elements. (author)

Selection of tracers for oil and gas evaluation

International Nuclear Information System (INIS)

Bjoernstad, T.

1991-08-01

The importance of tracer tests in reservoir descriptions is increasingly acknowledged by reservoir engineers as a method to obtain valuable dynamic information from the reservoir. The report describes the ''state-of-the art'' on tracer technology for interwell investigations. Experiences gained from a number of reported field tracer tests are reviewed, and results from detailed laboratory investigations on the static and dynamic behavior of various tracer molecules are discussed. A critical evaluation of the applicability of the various identified tracers is provided. Present and future trends in the development of tracer technology for reservoir description are sketched. 64 refs., 12 figs., 2 tabs

Using rare earth element tracers and neutron activation analysis to study rill erosion process

International Nuclear Information System (INIS)

Li Mian; Li Zhanbin; Ding Wengfeng; Liu Puling; Yao Wenyi

2006-01-01

Spatially averaged soil erosion data provide little information on the process of rill erosion. The dynamically varied data on the temporal and spatial distributions in the rill erosion process are needed to better understand the erosion process and reveal its innate characteristics. The objectives of this study were to examine the feasibility and effectiveness of rare earth element (REE) tracers and the neutron activation analysis (NAA) method on the study of the rill erosion process and to reveal quantitatively the relationships and characteristics of temporal and spatial distributions of sediment yield in rill erosion. Four REEs were used to study the changeable process of rill erosion at 4 slope positions. Four water inflow rates were applied to a 0.3x5 m soil bed at 3 slopes of 10.5%, 15.8% and 21.2% in scouring experiments. All of the runoff was collected in the experiment. Each sample was air-dried and well mixed. Then 20 g of each sample was sieved through 100-mesh and about a 50 mg sample was weighed for analysis of the four elemental compositions by NAA. Results indicate that the REE tracers and NAA method can be used to not only quantitatively determine soil erosion amounts on different slope segments, but also to reveal the changeable process of rill erosion amount. All of the relative errors of the experimental results were less than 25%, which is considered satisfactory on the study of rill erosion process

Using rare earth element tracers and neutron activation analysis to study rill erosion process

Energy Technology Data Exchange (ETDEWEB)

Li Mian [Yellow River Institute of Hydraulic Research, Yellow River Conservancy Commission, Key Laboratory of Yellow River Sediment Research of Ministry of Water Resources, Shunhelu 45, Zhengzhou, Henan 450003 (China)]. E-mail: hnli-mian@163.com; Li Zhanbin [Xi' an University of Technology, Xi' an, Shaanxi 710048 (China); Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100 (China); Ding Wengfeng [Institute of Soil and Water Conservation, Yangtse River' s Scientific Research Institute, Wuhan, Hubei 430010 (China); Liu Puling [Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100 (China); Yao Wenyi [Yellow River Institute of Hydraulic Research, Yellow River Conservancy Commission, Key Laboratory of Yellow River Sediment Research of Ministry of Water Resources, Shunhelu 45, Zhengzhou, Henan 450003 (China)

2006-03-15

Spatially averaged soil erosion data provide little information on the process of rill erosion. The dynamically varied data on the temporal and spatial distributions in the rill erosion process are needed to better understand the erosion process and reveal its innate characteristics. The objectives of this study were to examine the feasibility and effectiveness of rare earth element (REE) tracers and the neutron activation analysis (NAA) method on the study of the rill erosion process and to reveal quantitatively the relationships and characteristics of temporal and spatial distributions of sediment yield in rill erosion. Four REEs were used to study the changeable process of rill erosion at 4 slope positions. Four water inflow rates were applied to a 0.3x5 m soil bed at 3 slopes of 10.5%, 15.8% and 21.2% in scouring experiments. All of the runoff was collected in the experiment. Each sample was air-dried and well mixed. Then 20 g of each sample was sieved through 100-mesh and about a 50 mg sample was weighed for analysis of the four elemental compositions by NAA. Results indicate that the REE tracers and NAA method can be used to not only quantitatively determine soil erosion amounts on different slope segments, but also to reveal the changeable process of rill erosion amount. All of the relative errors of the experimental results were less than 25%, which is considered satisfactory on the study of rill erosion process.

Abdominal wall reconstruction for large incisional hernia restores expiratory lung function

DEFF Research Database (Denmark)

Jensen, Kristian K; Backer, Vibeke; Jorgensen, Lars N

2017-01-01

BACKGROUND: Respiratory complications secondary to intermittent intra-abdominal hypertension and/or atelectasis are common after abdominal wall reconstruction for large incisional hernias. It is unknown if the respiratory function of this patient group is affected long term or impairs activities...... of daily living. We hypothesized that abdominal wall reconstruction for large incisional hernia would not lead to improved, long-term pulmonary function or respiratory quality of life. METHODS: Eighteen patients undergoing open abdominal wall reconstruction with mesh for a large incisional hernia...... (horizontal fascial defect width >10 cm) were compared with 18 patients with an intact abdominal wall who underwent colorectal resection. Patients were examined pre- and 1-year postoperatively. Examined measures included forced vital capacity, forced expiratory volume in first second, peak expiratory flow...

Don't Forget the Abdominal Wall: Imaging Spectrum of Abdominal Wall Injuries after Nonpenetrating Trauma.

Science.gov (United States)

Matalon, Shanna A; Askari, Reza; Gates, Jonathan D; Patel, Ketan; Sodickson, Aaron D; Khurana, Bharti

2017-01-01

Abdominal wall injuries occur in nearly one of 10 patients coming to the emergency department after nonpenetrating trauma. Injuries range from minor, such as abdominal wall contusion, to severe, such as abdominal wall rupture with evisceration of abdominal contents. Examples of specific injuries that can be detected at cross-sectional imaging include abdominal muscle strain, tear, or hematoma, including rectus sheath hematoma (RSH); traumatic abdominal wall hernia (TAWH); and Morel-Lavallée lesion (MLL) (closed degloving injury). These injuries are often overlooked clinically because of (a) a lack of findings at physical examination or (b) distraction by more-severe associated injuries. However, these injuries are important to detect because they are highly associated with potentially grave visceral and vascular injuries, such as aortic injury, and because their detection can lead to the diagnosis of these more clinically important grave traumatic injuries. Failure to make a timely diagnosis can result in delayed complications, such as bowel hernia with potential for obstruction or strangulation, or misdiagnosis of an abdominal wall neoplasm. Groin injuries, such as athletic pubalgia, and inferior costochondral injuries should also be considered in patients with abdominal pain after nonpenetrating trauma, because these conditions may manifest with referred abdominal pain and are often included within the field of view at cross-sectional abdominal imaging. Radiologists must recognize and report acute abdominal wall injuries and their associated intra-abdominal pathologic conditions to allow appropriate and timely treatment. © RSNA, 2017.

Correlation between intra-abdominal pressure and pulmonary volumes after superior and inferior abdominal surgery

Directory of Open Access Journals (Sweden)

Roberto de Cleva

2014-07-01

Full Text Available OBJECTIVE:Patients undergoing abdominal surgery are at risk for pulmonary complications. The principal cause of postoperative pulmonary complications is a significant reduction in pulmonary volumes (FEV1 and FVC to approximately 65-70% of the predicted value. Another frequent occurrence after abdominal surgery is increased intra-abdominal pressure. The aim of this study was to correlate changes in pulmonary volumes with the values of intra-abdominal pressure after abdominal surgery, according to the surgical incision in the abdomen (superior or inferior.METHODS:We prospectively evaluated 60 patients who underwent elective open abdominal surgery with a surgical time greater than 240 minutes. Patients were evaluated before surgery and on the 3rd postoperative day. Spirometry was assessed by maximal respiratory maneuvers and flow-volume curves. Intra-abdominal pressure was measured in the postoperative period using the bladder technique.RESULTS:The mean age of the patients was 56±13 years, and 41.6% 25 were female; 50 patients (83.3% had malignant disease. The patients were divided into two groups according to the surgical incision (superior or inferior. The lung volumes in the preoperative period showed no abnormalities. After surgery, there was a significant reduction in both FEV1 (1.6±0.6 L and FVC (2.0±0.7 L with maintenance of FEV1/FVC of 0.8±0.2 in both groups. The maximum intra-abdominal pressure values were similar (p= 0.59 for the two groups. There was no association between pulmonary volumes and intra-abdominal pressure measured in any of the groups analyzed.CONCLUSIONS:Our results show that superior and inferior abdominal surgery determines hypoventilation, unrelated to increased intra-abdominal pressure. Patients at high risk of pulmonary complications should receive respiratory care even if undergoing inferior abdominal surgery.

Correlation between intra-abdominal pressure and pulmonary volumes after superior and inferior abdominal surgery.

Science.gov (United States)

Cleva, Roberto de; Assumpção, Marianna Siqueira de; Sasaya, Flavia; Chaves, Natalia Zuniaga; Santo, Marco Aurelio; Fló, Claudia; Lunardi, Adriana C; Jacob Filho, Wilson

2014-07-01

Patients undergoing abdominal surgery are at risk for pulmonary complications. The principal cause of postoperative pulmonary complications is a significant reduction in pulmonary volumes (FEV1 and FVC) to approximately 65-70% of the predicted value. Another frequent occurrence after abdominal surgery is increased intra-abdominal pressure. The aim of this study was to correlate changes in pulmonary volumes with the values of intra-abdominal pressure after abdominal surgery, according to the surgical incision in the abdomen (superior or inferior). We prospectively evaluated 60 patients who underwent elective open abdominal surgery with a surgical time greater than 240 minutes. Patients were evaluated before surgery and on the 3rd postoperative day. Spirometry was assessed by maximal respiratory maneuvers and flow-volume curves. Intra-abdominal pressure was measured in the postoperative period using the bladder technique. The mean age of the patients was 56 ± 13 years, and 41.6% 25 were female; 50 patients (83.3%) had malignant disease. The patients were divided into two groups according to the surgical incision (superior or inferior). The lung volumes in the preoperative period showed no abnormalities. After surgery, there was a significant reduction in both FEV1 (1.6 ± 0.6 L) and FVC (2.0 ± 0.7 L) with maintenance of FEV1/FVC of 0.8 ± 0.2 in both groups. The maximum intra-abdominal pressure values were similar (p=0.59) for the two groups. There was no association between pulmonary volumes and intra-abdominal pressure measured in any of the groups analyzed. Our results show that superior and inferior abdominal surgery determines hypoventilation, unrelated to increased intra-abdominal pressure. Patients at high risk of pulmonary complications should receive respiratory care even if undergoing inferior abdominal surgery.

Lateral abdominal wall hematoma as a rare complication after carotid artery stenting: a case report

Directory of Open Access Journals (Sweden)

Satomi Jyunichiro

2009-11-01

Full Text Available Abstract Abdominal wall hematoma is a rare and life-threatening complication after carotid artery stenting (CAS, but it can occur when activated clotting time is prolonged. We report a right lateral abdominal wall hematoma caused by rupture of the superficial circumflex iliac artery after CAS in a 72-year-old man with severe stenosis of the origin of the right internal carotid artery. We performed CAS for the targeted lesion while activated clotting time exceeded 300 seconds. After 2 hours, he complained of right lateral abdominal pain. Abdominal computed tomography revealed an extensive hematoma in the right lateral abdominal wall. Activated clotting time was 180 seconds at this point. Seven hours later, he developed hypotension and hemoglobin level dropped to 11.3 g/dl. Subsequent computed tomography showed enlargement of the hematoma. Emergent selective angiography of the external iliac artery revealed active bleeding from the right superficial circumflex iliac artery. Transcatheter arterial embolization with Gelfoam and microcoils was performed successfully. With more CAS procedures being performed, it is important for endovascular surgeons and radiologists to consider the possibility of abdominal wall hematoma in this situation.

Physicians' Abdominal Auscultation

DEFF Research Database (Denmark)

John, Gade; Peter, Kruse; Andersen, Ole Trier

1998-01-01

Background: Abdominal auscultation has an important position in the physical examination of the abdomen. Little is known about rater agreement. The aim of this study was to describe rater agreement and thus, indirectly, the value of the examination. Methods: In a semi-virtual setup 12 recordings...... subjects and in patients with intestinal obstruction was acceptable for a clinical examination. Abdominal auscultation is a helpful clinical examination in patients with acute abdominal pain....

Associations of objectively measured physical activity and abdominal fat distribution.

Science.gov (United States)

Philipsen, Annelotte; Hansen, Anne-Louise Smidt; Jørgensen, Marit Eika; Brage, Søren; Carstensen, Bendix; Sandbaek, Annelli; Almdal, Thomas Peter; Gram, Jeppe; Pedersen, Erling Bjerregaard; Lauritzen, Torsten; Witte, Daniel Rinse

2015-05-01

Visceral adipose tissue (VAT) and physical activity are both independent predictors of Type 2 diabetes. Physical activity and overall obesity are inversely associated with each other. Yet the nature of the association between objectively measured dimensions of physical activity and abdominal fat distribution has not been well characterized. We aimed to do so in a middle-age to elderly population at high risk of diabetes. A cross-sectional analysis of 1134 participants of the ADDITION-PRO study. VAT and subcutaneous adipose tissue (SAT) were assessed one-dimensionally by ultrasonography and physical activity with combined accelerometry and HR monitoring. Linear regression of physical activity energy expenditure (PAEE) and time spent in different physical activity intensity levels on VAT and SAT was performed. Median body mass index (BMI) was 26.6 kg·m and PAEE was 28.1 kJ·kg·d, with 18.9 h·d spent sedentary, 4.5 h·d in light-intensity physical activity, and 0.4 h·d in moderate-intensity physical activity. PAEE was significantly negatively associated with VAT, and in women, PAEE was also significantly negatively associated with SAT. The difference in VAT was -1.1 mm (95% confidence interval [CI] = -1.8 to -0.3) per 10-kJ·kg·d increment, and the corresponding difference in SAT for women was -0.6 mm (95% CI = -1.2 to -0.04) in models adjusted for age, sex, and waist circumference. Exchanging 1 h of light physical activity with moderate physical activity was significantly associated with VAT (-4.5 mm, 95% CI = -7.6 to -1.5). Exchanging one sedentary hour with light physical activity was significantly associated with both VAT (-0.9 mm, 95% CI = -0.1 to -1.8) and SAT (-0.4 mm, 95% CI = -0.0 to -0.7). In this population with low physical activity levels, cross-sectional findings indicate that increasing overall physical activity and decreasing time spent sedentary is important to avoid the accumulation of metabolically deleterious VAT.

The therapeutic impact of abdominal ultrasound in patients with acute abdominal symptoms

International Nuclear Information System (INIS)

Dhillon, S.; Halligan, S.; Goh, V.; Matravers, P.; Chambers, A.; Remedios, D.

2002-01-01

AIM: The technical performance of abdominal ultrasound in the investigation of acute abdominal pain has been thoroughly investigated but its therapeutic effects are less well understood. We aimed to determine the therapeutic effect of abdominal ultrasound in the investigation of acute abdominal pain. MATERIAL AND METHODS: A pre- and post-intervention observational study design was used to determine the diagnostic and therapeutic effects of abdominal ultrasound for acute abdominal pain. Referring clinicians completed a pre-ultrasound questionnaire that detailed their leading diagnosis, confidence in this and intended management in 100 consecutive adult patients. Following ultrasound a second questionnaire was completed. This again detailed the leading diagnosis, confidence in this and their intended management. Clinicians quantified the management contribution of ultrasound both for the individual case in question and in their clinical experience generally. RESULTS: The leading diagnosis was either confirmed or rejected in 72 patients and a new diagnosis provided where no prior differential diagnosis existed in 10. Diagnostic confidence increased significantly following ultrasound (mean score 6·5 pre-ultrasound vs 7·6 post-ultrasound, P < 0·001). Intended management changed following ultrasound in 22 patients; 15 intended laparotomies were halted and a further seven patients underwent surgery where this was not originally intended. Ultrasound was rated either 'very' or 'moderately' helpful in 87% of patients, with 99% of clinicians finding it either 'very' or 'moderately' helpful generally. CONCLUSION: Abdominal ultrasound has considerable diagnostic and therapeutic effect in the setting of acute abdominal pain. Dhillon, S. et al. (2002)

A description of the atmospheric tracer technology used at the J.R.C.-Ispra

International Nuclear Information System (INIS)

Gaglione, P.

1988-01-01

Atmospheric tracers are a versatile tool that can be used in conjunction with basic meteorological investigations and models to gain a better understanding of the dynamical behaviour of atmospheric pollutants on both the local and regional scales. The tracer activity was initiated at Ispra about ten years ago, with the aim of providing an experimental support to the research activity carried out in the field of air pollution modeling. At the time the area of interest was mainly related to the atmospheric dispersion on a local scale of pollutants released from stacks of power stations, therefore a technique using SF 6 as a tracer was implemented. In the last few years some efforts have been devoted also to the determination of the atmospheric dispersion parameters in the mesoscale and in the regional scale. Due to the limitations in the use of SF 6 over these distances, a new technique utilizing perfluorocarbons (C 7 F 14 and C 8 F 16 ) as tracers has been implemented and positively tested in the field, even though limited until now to a few short range experiments. The purpose of this presentation is to describe the tracer technology developments at the J.R.C.-Ispra including the main results obtained in different field studies

Tracer transport in fractured rocks

International Nuclear Information System (INIS)

Tsang, C.F.; Tsang, Y.W.; Hale, F.V.

1988-07-01

Recent interest in the safety of toxic waste underground disposal and nuclear waste geologic repositories has motivated many studies of tracer transport in fractured media. Fractures occur in most geologic formations and introduce a high degree of heterogeneity. Within each fracture, the aperture is not constant in value but strongly varying. Thus for such media, tracer tends to flow through preferred flowpaths or channels within the fractures. Along each of these channels, the aperture is also strongly varying. A detailed analysis is carried out on a 2D single fracture with variable apertures and the flow through channels is demonstrated. The channels defined this way are not rigidly set pathways for tracer transport, but are the preferred flow paths in the sense of stream-tubes in the potential theory. It is shown that such variable-aperture channels can be characterized by an aperture probability distribution function, and not by the exact deterministic geometric locations. We also demonstrate that the 2D tracer transport in a fracture can be calculated by a model of a system of 1D channels characterized by this distribution function only. Due to the channeling character of tracer transport in fractured rock, random point measurements of tracer breakthrough curves may give results with a wide spread in value due to statistical fluctuations. The present paper suggests that such a wide spread can probably be greatly reduced by making line/areal (or multiple) measurements covering a few spatial correlation lengths. 13 refs., 11 figs., 1 tab

Tracers of air-sea gas exchange

International Nuclear Information System (INIS)

Liss, P.S.

1988-01-01

The flux of gas across the air-sea interface is determined by the product of the interfacial concentration difference driving the exchange and a rate constant, often termed the transfer velocity. The concentration-difference term is generally obtained by direct measurement, whereas more indirect approaches are required to estimate the transfer velocity and its variation as a function of controlling parameters such as wind and sea state. Radioactive tracers have proved particularly useful in the estimation of air-sea transfer velocities and, recently, stable purposeful tracers have also started to be used. In this paper the use of the following tracers to determine transfer velocities at the sea surface is discussed: natural and bomb-produced 14 C, dissolved oxygen, 222 Rn and sulphur hexafluoride. Other topics covered include the relation between transfer velocity and wind speed as deduced from tracer and wind-tunnel studies, and the discrepancy between transfer velocities determined by using tracers and from eddy correlation measurements in the atmosphere. (author)

[Implementationof a low FODMAP dietforfunctional abdominal pain].

Science.gov (United States)

Baranguán Castro, María Luisa; Ros Arnal, Ignacio; García Romero, Ruth; Rodríguez Martínez, Gerardo; Ubalde Sainz, Eduardo

2018-04-20

The low FODMAP diet (fermentable oligosaccharides, monosaccharides, disaccharides, and polyols) has shown to be effective in adult patients with irritable bowel syndrome, but there are few studies on paediatric patients. The aim of this study is to assess the implementation and the outcomes of a low FODMAP diet in the treatment of functional abdominal pain in children from a Mediterranean area. A table was designed in which foods were classified according to their FODMAP content, as well as a 'Symptoms and Stools Diary'. A prospective study was conducted on children with functional abdominal pain in our Paediatric Gastroenterology Unit. A total of 22 patients were enrolled in the trial, and 20 completed it. Data were collected of the abdominal pain features over a period of 3 days, and then patients followed a two-week low FODMAP diet. Afterwards, information about abdominal pain features was collected again. After the diet, they showed fewer daily abdominal pain episodes compared to baseline (1.16 [IQR: 0.41-3.33] versus 2 [IQR: 1.33-6.33] daily episodes, P=.024), less pain severity compared to baseline (1.41cm [IQR: 0.32-5.23] versus 4.63cm [IQR: 2.51-6.39] measured by 10-cm Visual Analogue Scale, P=.035), less interference with daily activities, and less gastrointestinal symptoms. Only 15% of patients found it difficult to follow the diet. The implementation of a low FODMAP diet for 2 weeks in a Mediterranean paediatric population diagnosed with functional abdominal pain is possible with adapted diets. It was highly valued by patients, and they showed an improvement in abdominal pain symptoms assessed by objective methods. Copyright © 2018. Publicado por Elsevier España, S.L.U.

Chronic Abdominal Wall Pain.

Science.gov (United States)

Koop, Herbert; Koprdova, Simona; Schürmann, Christine

2016-01-29

Chronic abdominal wall pain is a poorly recognized clinical problem despite being an important element in the differential diagnosis of abdominal pain. This review is based on pertinent articles that were retrieved by a selective search in PubMed and EMBASE employing the terms "abdominal wall pain" and "cutaneous nerve entrapment syndrome," as well as on the authors' clinical experience. In 2% to 3% of patients with chronic abdominal pain, the pain arises from the abdominal wall; in patients with previously diagnosed chronic abdominal pain who have no demonstrable pathological abnormality, this likelihood can rise as high as 30% . There have only been a small number of clinical trials of treatment for this condition. The diagnosis is made on clinical grounds, with the aid of Carnett's test. The characteristic clinical feature is strictly localized pain in the anterior abdominal wall, which is often mischaracterized as a "functional" complaint. In one study, injection of local anesthesia combined with steroids into the painful area was found to relieve pain for 4 weeks in 95% of patients. The injection of lidocaine alone brought about improvement in 83-91% of patients. Long-term pain relief ensued after a single lidocaine injection in 20-30% of patients, after repeated injections in 40-50% , and after combined lidocaine and steroid injections in up to 80% . Pain that persists despite these treatments can be treated with surgery (neurectomy). Chronic abdominal wall pain is easily diagnosed on physical examination and can often be rapidly treated. Any physician treating patients with abdominal pain should be aware of this condition. Further comparative treatment trials will be needed before a validated treatment algorithm can be established.

The ATLAS DDM Tracer monitoring framework

CERN Document Server

ZANG, D; The ATLAS collaboration; BARISITS, M; LASSNIG, M; Andrew STEWART, G; MOLFETAS, A; BEERMANN, T

2012-01-01

The DDM Tracer Service is aimed to trace and monitor the atlas file operations on the Worldwide LHC Computing Grid. The volume of traces has increased significantly since the service started in 2009. Now there are about ~5 million trace messages every day and peaks of greater than 250Hz, with peak rates continuing to climb, which gives the current service structure a big challenge. Analysis of large datasets based on on-demand queries to the relational database management system (RDBMS), i.e. Oracle, can be problematic, and have a significant effect on the database's performance. Consequently, We have investigated some new high availability technologies like messaging infrastructure, specifically ActiveMQ, and key-value stores. The advantages of key value store technology are that they are distributed and have high scalability; also their write performances are usually much better than RDBMS, all of which are very useful for the Tracer service. Indexes and distributed counters have been also tested to improve...

Intra-Abdominal Hypertension and Abdominal Compartment Syndrome in Association with Ruptured Abdominal Aortic Aneurysm in the Endovascular Era: Vigilance Remains Critical

Directory of Open Access Journals (Sweden)

Matthew C. Bozeman

2012-01-01

In this review, we describe published experience with IAH and ACS complicating abdominal vascular catastrophes, experience with ACS complicating endovascular repair of rAAAs, and techniques for management of the abdominal wound. Vigilance and appropriate management of IAH and ACS remains critically important in decreasing morbidity and optimizing survival following catastrophic intra-abdominal vascular events.

Torsion of abdominal appendages presenting with acute abdominal pain

International Nuclear Information System (INIS)

Al-Jaberi, Tareq M.; Gharabeih, Kamal I.; Yaghan, Rami J.

2000-01-01

Diseases of abnormal appendages are rare causes of abdominal pain in all age groups. Nine patients with torsion and infraction of abdominal appendages were retrospectively reviewed. Four patients had torsion and infarction of the appendices epiploicae, four patients had torsion and infarction of the falciform ligament. The patient with falciform ligament disease represents the first reported case of primary torsion and infarction of the falciform ligament, and the patient with the transverse colon epiplocia represents the first reported case of vibration-induced appendix epiplocia torsion and infarction. The patient with the falciform ligament disease presented with a tender upper abdominal mass and the remaining patients were operated upon with the preoperative diagnosis of acute appendicitis. The presence of normal appendix with free serosanguinous fluid in the peritoneal cavity should raise the possibility of a disease and calls for further evaluation of the intra-abdominal organs. If the diagnosis is suspected preoperatively, CT scan and ultrasound may lead to a correct diagnosis and possibly conservative management. Laparoscopy is playing an increasing diagnostic and therapeutic role in such situations. (author)

TracerLPM (Version 1): An Excel® workbook for interpreting groundwater age distributions from environmental tracer data

Science.gov (United States)

Jurgens, Bryant C.; Böhlke, J.K.; Eberts, Sandra M.

2012-01-01

TracerLPM is an interactive Excel® (2007 or later) workbook program for evaluating groundwater age distributions from environmental tracer data by using lumped parameter models (LPMs). Lumped parameter models are mathematical models of transport based on simplified aquifer geometry and flow configurations that account for effects of hydrodynamic dispersion or mixing within the aquifer, well bore, or discharge area. Five primary LPMs are included in the workbook: piston-flow model (PFM), exponential mixing model (EMM), exponential piston-flow model (EPM), partial exponential model (PEM), and dispersion model (DM). Binary mixing models (BMM) can be created by combining primary LPMs in various combinations. Travel time through the unsaturated zone can be included as an additional parameter. TracerLPM also allows users to enter age distributions determined from other methods, such as particle tracking results from numerical groundwater-flow models or from other LPMs not included in this program. Tracers of both young groundwater (anthropogenic atmospheric gases and isotopic substances indicating post-1940s recharge) and much older groundwater (carbon-14 and helium-4) can be interpreted simultaneously so that estimates of the groundwater age distribution for samples with a wide range of ages can be constrained. TracerLPM is organized to permit a comprehensive interpretive approach consisting of hydrogeologic conceptualization, visual examination of data and models, and best-fit parameter estimation. Groundwater age distributions can be evaluated by comparing measured and modeled tracer concentrations in two ways: (1) multiple tracers analyzed simultaneously can be evaluated against each other for concordance with modeled concentrations (tracer-tracer application) or (2) tracer time-series data can be evaluated for concordance with modeled trends (tracer-time application). Groundwater-age estimates can also be obtained for samples with a single tracer measurement at one

Intra-abdominal pressure and abdominal compartment syndrome in acute general surgery.

LENUS (Irish Health Repository)

Sugrue, Michael

2012-01-31

BACKGROUND: Intra-abdominal pressure (IAP) is a harbinger of intra-abdominal mischief, and its measurement is cheap, simple to perform, and reproducible. Intra-abdominal hypertension (IAH), especially grades 3 and 4 (IAP > 18 mmHg), occurs in over a third of patients and is associated with an increase in intra-abdominal sepsis, bleeding, renal failure, and death. PATIENTS AND METHODS: Increased IAP reading may provide an objective bedside stimulus for surgeons to expedite diagnostic and therapeutic work-up of critically ill patients. One of the greatest challenges surgeons and intensivists face worldwide is lack of recognition of the known association between IAH, ACS, and intra-abdominal sepsis. This lack of awareness of IAH and its progression to ACS may delay timely intervention and contribute to excessive patient resuscitation. CONCLUSIONS: All patients entering the intensive care unit (ICU) after emergency general surgery or massive fluid resuscitation should have an IAP measurement performed every 6 h. Each ICU should have guidelines relating to techniques of IAP measurement and an algorithm for management of IAH.

Live controls for radioisotope tracer food chain experiments using meiofauna

International Nuclear Information System (INIS)

Montagna, P.A.

1983-01-01

Formalin poisoned samples are inadequate for measuring the amount of label to be subtracted as control values for certain food chain studies that employ radioactive tracers. In some studies, tracer is added just before incubation to label ''food'' during the feeding study. Commonly, parallel, poisoned incubations are used to distinguish between biotic and abiotic label incorporation. But, a poisoned control does not account for label that could enter a consumer via active transport, epicuticular microfloral uptake, or grazing on labeled, non-food particles. Experiments were performed to test if label uptake is greater in live non-grazing than dead organisms. Marine benthic meiofauna incoporate from 3 to 133 times more tracer when they are alive and not grazing than when they are formalin killed. These results suggest that control experiments with live animals be performed to measure all processes by which label can enter consumers in food chain experiments. (orig.)

Doublet Tracer Testing in Klamath Falls, Oregon

Energy Technology Data Exchange (ETDEWEB)

Gudmundsson, J S; Johnson, S E; Horne, R N; Jackson, P B [Pet. Eng. Dept., Stanford University; Culver, G G [Geo-Heat Center, Oregon Institute of Technology, Klamath Falls, OR

0000-12-30

A tracer test was carried out in a geothermal doublet system to study the injection behavior of a developed reservoir known to be fractured. The doublet produces about 320 gpm of 160 degrees Fahrenheit water that is used for space heating and then injected; the wells are spaced 250 ft apart. Tracer breakthrough was observed in 2 hours and 45 minutes in the production well, indicating fracture flow. However, the tracer concentrations were low and indicated porous media flow; the tracers mixed with a reservoir volume much larger than a fracture.

Tracer a application in marine outfall studies

International Nuclear Information System (INIS)

Genders, S.

1979-01-01

The applicability of radioactive and fluorescent tracers for field studies to predict or investigate waste water transport and dispersion from marine outfalls is evaluated. The application of either instantaneous or continuous tracer release, 'in situ' detection of tracers and data processing are considered. The necessity of a combined use of tracer techniques and conventional hydrographic methods for a statistical prediction of transport and dillution of waste water are pointed out. A procedure to determine an outlet distance from the coast, which satisfy bathing water criteria is outlined. (M.A.) [pt

Doublet Tracer Testing in Klamath Falls, Oregon

Energy Technology Data Exchange (ETDEWEB)

Gudmundsson, J.S.; Johnson, S.E.; Horne, R.N.; Jackson, P. B. [Pet. Eng. Dept., Stanford University; Culver, G.G. [Geo-Heat Center, Oregon Institute of Technology, Klamath Falls, OR

0001-01-01

A tracer test was carried out in a geothermal doublet system to study the injection behavior of a developed reservoir known to be fractured. The doublet produces about 320 gpm of 160 degrees Fahrenheit water that is used for space heating and then injected; the wells are spaced 250 ft apart. Tracer breakthrough was observed in 2 hours and 45 minutes in the production well, indicating fracture flow. However, the tracer concentrations were low and indicated porous media flow; the tracers mixed with a reservoir volume much larger than a fracture.

Development of some new Aza and Thia complex as alternative tracers for oil reservoirs

International Nuclear Information System (INIS)

Silva, Lauris L.; Donnici, Claudio L.; Ayala, Jose D.

2009-01-01

A promising group of non-sorbing tracers are lanthanide ions complexed to organic anions, which yield a negatively charged complex. Besides, this lanthanide ion could be chosen which, in its non-complexed form, is very insoluble in groundwater and thus no severe background concentrations problem would arise. The lanthanide elements may be used as tracers since they present good solubility in water, when complexed, and the nuclides have high neutron cross sections, they may be used as activable tracers under neutron irradiation in order to evaluate the efficiency of the petroleum production processes. For this purpose, tracers must be soluble in the aqueous phase and be insoluble in the organic phase, they also must not be adsorbed on the internal microporous rock formations and be easily detectable. Lanthanide complexes with DTPA and thiodicarboxylic acid ligands are an alternative to the development of these novel tracers since their properties may be chemically adjusted. (author)

Retrospective comparison of abdominal ultrasonography and radiography in the investigation of feline abdominal disease

Science.gov (United States)

Won, Wylen Wade; Sharma, Ajay; Wu, Wenbo

2015-01-01

Abdominal radiography and ultrasonography are commonly used as part of the initial diagnostic plan for cats with nonspecific signs of abdominal disease. This retrospective study compared the clinical usefulness of abdominal radiography and ultrasonography in 105 feline patients with signs of abdominal disease. The final diagnosis was determined more commonly with ultrasonography (59%) compared to radiography (25.7%). Ultrasonography was also able to provide additional clinically relevant information in 76% of cases, and changed or refined the diagnosis in 47% of cases. Based on these findings, ultrasonography may be sufficient as an initial diagnostic test for the investigation of feline abdominal disease. PMID:26483582

Tracers vs. trajectories in a coastal region

Science.gov (United States)

Engqvist, A.; Döös, K.

2008-12-01

Two different methods of estimating the water exchange through a Baltic coastal region have been used, consisting of particle trajectories and passive tracers. Water is traced from and to a small discharge region near the coast. The discharge material in this region is treated as zero dimensional particles or tracers with neutral buoyancy. The real discharge material could be a leakage of radio-nuclides through the sea floor from an underground repository of nuclear waste. Water exchange rates between the discharge region and the model domain are estimated using both forward and backward trajectories as well as passive tracers. The Lagrangian trajectories can account for the time evolution of the water exchange while the tracers give one average age per model grid box. Water exchange times such as residence time, age and transient times have been calculated with trajectories but only the average age (AvA) for tracers. The trajectory calculations provide a more detailed time evolution than the tracers. On the other hand the tracers are integrated "on-line" simultaneously in the sea circulation model with the same time step while the Lagrangian trajectories are integrated "off-line" from the stored model velocities with its inherent temporal resolution, presently one hour. The sub-grid turbulence is parameterised as a Laplacian diffusion for the passive tracers and with an extra stochastic velocity for trajectories. The importance of the parameterised sub-grid turbulence for the trajectories is estimated to give an extra diffusion of the same order as the Laplacian diffusion by comparing the Lagrangian dispersions with and without parameterisation. The results of the different methods are similar but depend on the chosen diffusivity coefficient with a slightly higher correlation between trajectories and tracers when integrated with a lower diffusivity coefficient.

[Differential diagnosis of abdominal pain].

Science.gov (United States)

Frei, Pascal

2015-09-02

Despite the frequency of functional abdominal pain, potentially dangerous causes of abdominal pain need to be excluded. Medical history and clinical examination must focus on red flags and signs for imflammatory or malignant diseases. See the patient twice in the case of severe and acute abdominal pain if lab parameters or radiological examinations are normal. Avoid repeated and useless X-ray exposure whenever possible. In the case of subacute or chronic abdominal pain, lab tests such as fecal calprotectin, helicobacter stool antigen and serological tests for celiac disease are very useful. Elderly patients may show atypical or missing clinical signs. Take care of red herrings and be skeptical whether your initial diagnosis is really correct. Abdominal pain can frequently be an abdominal wall pain.

Circulation of cerebrospinal fluid. Comparative study of various tracers

International Nuclear Information System (INIS)

Bok, B.; Thebault, B.; Cavailloles, F.; Aboulker, J.

1977-01-01

The dynamics of cerebrospinal fluid in the spinal subarachnoid space is studied by gammamyelography. There are still controversies about the ideal properties of the tracer to be used. The influence of the tracer's molecular weight on the kinetic of ascent in the medullar cerebrospinal fluid with a view to rating the criterias for choice of an available radiopharmaceutical was evaluated. Three compounds injected simultaneously through a lombar puncture were compared: indium 111 labelled transferrin, iodine 131 labelled human serum albumin and technetium 99m labelled diethylenetriaminepentaacetic acid. The individual stability of the compounds and a possible interference between them was investigated especially by electrophoretic technics. A spectrometric study showed that it is possible to simultaneously identify and count each of the isotopes included in the mixture on the detector device: an hybrid scanner. The comparison of linear activity profils collected on phantoms and on ten patients showed a similar fate of the three compounds during the first hours of the investigation studying the ascent of tracers into basal cisterns either in normal or pathological patients. It is therefore concluded that molecular weight does not influence in a detectable manner the spinal C.S.F. kinetics of the radiopharmaceuticals. This allows the use of the most convenient and best tolerated tracer from the dosimetric and toxicological stand point [fr

Prevalência e fatores associados à obesidade abdominal em adolescentes Prevalencia y factores asociados a la obesidad abdominal en adolescentes Prevalence of abdominal obesity and associated factors in adolescents

Directory of Open Access Journals (Sweden)

Marcelo Romanzini

2011-12-01

razones de odds (OR brutas y ajustadas con intervalo de confianza de 95%. RESULTADOS: La prevalencia de obesidad abdominal fue de 7,5%. Adolescentes del sexo masculino (OR 2,34; IC95% 1,27-4,32, de nivel económico intermediario (OR 2,89; IC95% 1,35-6,59 y alto (OR 2,98; IC95% 1,31-6,77 y que consumían bebidas alcohólicas de modo abusivo (OR 2,12; IC95% 1,10-4,09 presentaron mayores posibilidades de tener obesidad abdominal. CONCLUSIONES: La prevalencia de obesidad abdominal fue baja en comparación a los estudios internacionales. Además, se encontró que el sexo, el nivel económico y el consumo abusivo de alcohol se asociaron a la obesidad abdominal.OBJECTIVE: To determine the prevalence of abdominal obesity in adolescents and its association with demographic, economic and lifestyle variables in adolescents. METHODS: This cross-sectional study enrolled 644 adolescents (397 girls and 247 boys from 15 to 19 years old. Demographic (gender and age, economic (economic status, and lifestyle data (physical activity, diet, smoking, and alcohol consumption were collected. Abdominal obesity (primary outcome was evaluated based on the cut-off values for gender- and age-specific waist circumference. Data were analyzed using multivariate logistic regression, estimating the unadjusted and adjusted Odds Ratios (OR with a 95% confidence interval. RESULTS: The prevalence of abdominal obesity was 7.5%. Boys (OR 2.34; 95%CI 1.27-4.32 of intermediate (OR 2.89; 95%CI 1.35-6.59 and high socioeconomic status (OR 2.98; 95%CI 1.31-6.77 who had an excessive consumption of alcohol (OR 2.12; 95%CI 1.10-4.09 presented the highest chance of abdominal obesity. CONCLUSIONS: The prevalence of abdominal obesity was low in the studied population compared to rates reported in international studies. Gender, economic status and excessive alcohol consumption were associated with abdominal obesity.

Increased auditory startle reflex in children with functional abdominal pain.

Science.gov (United States)

Bakker, Mirte J; Boer, Frits; Benninga, Marc A; Koelman, Johannes H T M; Tijssen, Marina A J

2010-02-01

To test the hypothesis that children with abdominal pain-related functional gastrointestinal disorders have a general hypersensitivity for sensory stimuli. Auditory startle reflexes were assessed in 20 children classified according to Rome III classifications of abdominal pain-related functional gastrointestinal disorders (13 irritable bowel syndrome [IBS], 7 functional abdominal pain syndrome; mean age, 12.4 years; 15 girls) and 23 control subjects (14 girls; mean age, 12.3 years) using a case-control design. The activity of 6 left-sided muscles and the sympathetic skin response were obtained by an electromyogram. We presented sudden loud noises to the subjects through headphones. Both the combined response of 6 muscles and the blink response proved to be significantly increased in patients with abdominal pain compared with control subjects. A significant increase of the sympathetic skin response was not found. Comorbid anxiety disorders (8 patients with abdominal pain) or Rome III subclassification did not significantly affect these results. This study demonstrates an objective hyperresponsivity to nongastrointestinal stimuli. Children with abdominal pain-related functional gastrointestinal disorders may have a generalized hypersensitivity of the central nervous system. Copyright 2010 Mosby, Inc. All rights reserved.

Abdominal wall blocks in adults

DEFF Research Database (Denmark)

Børglum, Jens; Gögenür, Ismail; Bendtsen, Thomas F

2016-01-01

been introduced with success. Future research should also investigate the effect of specific abdominal wall blocks on neuroendocrine and inflammatory stress response after surgery.  Summary USG abdominal wall blocks in adults are commonplace techniques today. Most abdominal wall blocks are assigned......Purpose of review Abdominal wall blocks in adults have evolved much during the last decade; that is, particularly with the introduction of ultrasound-guided (USG) blocks. This review highlights recent advances of block techniques within this field and proposes directions for future research.......  Recent findings Ultrasound guidance is now considered the golden standard for abdominal wall blocks in adults, even though some landmark-based blocks are still being investigated. The efficiency of USG transversus abdominis plane blocks in relation to many surgical procedures involving the abdominal wall...

Pharmaceuticals as Groundwater Tracers - Applications and Limitations

Science.gov (United States)

Scheytt, T. J.; Mersmann, P.; Heberer, T.

2003-12-01

Pharmaceutically active substances and metabolites are found at concentrations up to the microgram/L-level in groundwater samples from the Berlin (Germany) area and from several other places world wide. Among the compounds detected in groundwater are clofibric acid, propyphenazone, diclofenac, ibuprofen, and carbamazepine. Clofibric acid, the active metabolite of clofibrate and etofibrate (blood lipid regulators) is detected in groundwater at maximum concentrations of 7300 ng/L. Among the most important input paths of drugs are excretion and disposal into the sewage system. Groundwater contamination is likely to be due to leaky sewage systems, influent streams, bank filtration, and irrigation with effluent water from sewage treatment plants. There are no known natural sources of the above mentioned pharmaceuticals. The use of pharmaceuticals as tracers may include: (a) Quantification of infiltration from underground septic tanks (b) Detection of leaky sewage systems / leaky sewage pipes (c) Estimation of the effectiveness of sewage treatment plants (d) Identification of transport pathways of other organic compounds (e) Quantification of surface water / groundwater interaction (f) Characterization of the biodegradation potential. The use of pharmaceuticals as tracers is limited by variations in input. These variations depend on the amount of drugs prescribed and used in the study area, the social structure of the community, the amount of hospital discharge, and temporal concentration variations. Furthermore, the analysis of trace amounts of pharmaceuticals is sophisticated and expensive and may therefore limit the applicability of pharmaceuticals as tracers. Finally, the transport and degradation behavior of pharmaceuticals is not fully understood. Preliminary experiments in the laboratory were conducted using sediment material and groundwater from the Berlin area to evaluate the transport and sorption behavior of selected drugs. Results of the column experiments

Using Tracer Technology to Characterize Contaminated Pipelines

Energy Technology Data Exchange (ETDEWEB)

Maresca, Joseph, W., Jr., Ph.D.; Bratton, Wesley, L., Ph.D., P.E.; Dickerson, Wilhelmina; Hales, Rochelle

2005-12-30

The Pipeline Characterization Using Tracers (PCUT) technique uses conservative and partitioning, reactive or other interactive tracers to remotely determine the amount of contaminant within a run of piping or ductwork. The PCUT system was motivated by a method that has been successfully used to characterize subsurface soil contaminants and is similar in operation to that of a gas chromatography column. By injecting a ?slug? of both conservative and partitioning tracers at one end (or section) of the piping and measuring the time history of the concentration of the tracers at the other end (or another section) of the pipe, the presence, location, and amount of contaminant within the pipe or duct can be determined. The tracers are transported along the pipe or duct by a gas flow field, typically air or nitrogen, which has a velocity that is slow enough so that the partitioning tracer has time to interact with the contaminant before the tracer slug completely passes over the contaminate region. PCUT not only identifies the presence of contamination, it also can locate the contamination along the pipeline and quantify the amount of residual. PCUT can be used in support of deactivation and decommissioning (D&D) of piping and ducts that may have been contaminated with hazardous chemicals such as chlorinated solvents, petroleum products, radioactive materials, or heavy metals, such as mercury.

A comparison of resting images from two myocardial perfusion tracers

International Nuclear Information System (INIS)

Anagnostopoulos, C.; Laney, R.; Pennell, D.; Proukakis, H.; Underwood, R.

1995-01-01

We have compared stress-redistribution and delayed rest thallium-201 with rest technetium-99m methoxyisobutylisonitrile (MIBI) tomograms in order to compare the tracers for the assessment of myocardial viability and to validate a rapid protocol combining the two tracers. We studied 30 consecutive patients with known or suspected coronary artery disease [group 1: 16 with normal left ventricular function, mean left ventricular ejection fraction (LVEF) 55%, SD 6%; group 2: 14 with abnormal function, mean LVEF 28%, SD 8%]. 201 Tl was injected during infusion of adenosine followed by acquisition of conventional stress and redistribution tomograms. On a separate day, 201 Tl was injected at rest with imaging 4 h later. 99m Tc-MIBI was then given at rest and imaging was performed. Three images were compared: redistribution 201 Tl, rest 201 Tl, and rest 99m Tc-MIBI. Tracer activity was classified visually and quantitatively in nine segments and segments with>50% activity were defined as containing clinically significant viable myocardium. Mean global tracer uptake as a percentage of maximum was similar in group 1 (rest 201 Tl 69%±12%, redistribution 201 Tl 69%±15%, rest 99m Tc-MIBI 70%±13%), but in group 2 mean tracer uptake was significantly greater in the rest 201 Tl images (59%±16%) than in redistribution 201 Tl images (53%±17%) or rest 99m Tc-MIBI images (53%±19%). Overall agreement for regional uptake score was excellent (κ from 0.79 to 0.84), although there were a significant number of segments with less uptake shown by redistribution 201 Tl and by rest 99m Tc-MIBI than by rest 201 Tl in group 2. The number of segments with significant viable myocardium in group 1 was very similar between the three images but in group 2 rest 201 Tl identified significantly more segments as viable than the other images. (orig./MG) (orig.). With 1 fig., 7 tabs

Dynamic CT in the abdominal organ, 2. Dynamics in the abdominal malignancies

Energy Technology Data Exchange (ETDEWEB)

Fukuda, K [Jikei Univ., Tokyo (Japan). School of Medicine

1980-03-01

The potential role of the abdominal dynamic CT in malignant tumors was evaluated. Among total of 112 cases dynamically studied included were, 22 cases of abdominal malignancies, renal cell carcinoma in 7, hepatocellular carcinoma in 7, metastatic liver tumor in 5, renal pelvic carcinoma in 2, and pancreatic cystadenocarcinoma in one. The results led to the following advantages of the abdominal dynamic CT over conventional CT. (1) The tumor thrombus and the lymphnode involvement could be better demonstrated. (2) The tumor vessels and the tumor stain could be depicted. (3) The extent of the tumor in the parenchyma could be better appreciated. The more invasive catheter angiography would likely to be replaced by the abdominal dynamic CT in the selected case.

Deaths from abdominal trauma: analysis of 1888 forensic autopsies

Directory of Open Access Journals (Sweden)

POLYANNA HELENA COELHO BORDONI

Full Text Available ABSTRACT Objective: to evaluate the epidemiological profile of deaths due to abdominal trauma at the Forensic Medicine Institute of Belo Horizonte, MG - Brazil. Methods: we conducted a retrospective study of the reports of deaths due to abdominal trauma autopsied from 2006 to 2011. Results: we analyzed 1.888 necropsy reports related to abdominal trauma. Penetrating trauma was more common than blunt one and gunshot wounds were more prevalent than stab wounds. Most of the individuals were male, brown-skinned, single and occupationally active. The median age was 34 years. The abdominal organs most injured in the penetrating trauma were the liver and the intestines, and in blunt trauma, the liver and the spleen. Homicide was the most prevalent circumstance of death, followed by traffic accidents, and almost half of the cases were referred to the Forensic Medicine Institute by a health unit. The blood alcohol test was positive in a third of the necropsies where it was performed. Cocaine and marijuana were the most commonly found substances in toxicology studies. Conclusion: in this sample. there was a predominance of penetrating abdominal trauma in young, brown and single men, the liver being the most injured organ.

Abdominal elephantiasis: a case report.

Science.gov (United States)

Hanna, Dominique; Cloutier, Richard; Lapointe, Roch; Desgagné, Antoine

2004-01-01

Elephantiasis is a well-known condition in dermatology usually affecting the legs and external genitalia. It is characterized by chronic inflammation and obstruction of the lymphatic channels and by hypertrophy of the skin and subcutaneous tissues. The etiology is either idiopathic or caused by a variety of conditions such as chronic filarial disease, leprosy, leishmaniasis, and chronic recurrent cellulites. Elephantiasis of the abdominal wall is very rare. A complete review of the English and French literature showed only two cases reported in 1966 and 1973, respectively. We report a third case of abdominal elephantiasis and we briefly review this entity. We present the case of a 51-year-old woman who had progressively developed an enormous pediculated abdominal mass hanging down her knees. The skin was thickened, hyperpigmented, and fissured. She had a history of multiple abdominal cellulites. She underwent an abdominal lipectomy. Histopathology of the specimen confirmed the diagnosis of abdominal elephantiasis. Abdominal elephantiasis is a rare disease that represents end-stage failure of lymph drainage. Lipectomy should be considered in the management of this condition.

Rapid dual-tracer PTSM+ATSM PET imaging of tumour blood flow and hypoxia: a simulation study

International Nuclear Information System (INIS)

Rust, T C; Kadrmas, D J

2006-01-01

Blood flow and hypoxia are interrelated aspects of physiology that affect cancer treatment and response. Cu-PTSM and Cu-ATSM are related PET tracers for blood flow and hypoxia, and the ability to rapidly image both tracers in a single scan would bring several advantages over conventional single-tracer techniques. Using dynamic imaging with staggered injections, overlapping signals for multiple PET tracers may be recovered utilizing information from kinetics and radioactive decay. In this work, rapid dual-tracer PTSM+ATSM PET was simulated and tested as a function of injection delay, order and relative dose for several copper isotopes, and the results were compared relative to separate single-tracer data. Time-activity curves representing a broad range of tumour blood flow and hypoxia levels were simulated, and parallel dual-tracer compartment modelling was used to recover the signals for each tracer. The main results were tested further using a torso phantom simulation of PET tumour imaging. Using scans as short as 30 minutes, the dual-tracer method provided measures of blood flow and hypoxia similar to single-tracer imaging. The best performance was obtained by injecting PTSM first and using a somewhat higher dose for ATSM. Comparable results for different copper isotopes suggest that tracer kinetics with staggered injections play a more important role than radioactive decay in the signal separation process. Rapid PTSM+ATSM PET has excellent potential for characterizing both tumour blood flow and hypoxia in a single, fast scan, provided that technological hurdles related to algorithm development and routine use can be overcome

Heat tracer test in an alluvial aquifer: Field experiment and inverse modelling

Science.gov (United States)

Klepikova, Maria; Wildemeersch, Samuel; Hermans, Thomas; Jamin, Pierre; Orban, Philippe; Nguyen, Frédéric; Brouyère, Serge; Dassargues, Alain

2016-09-01

Using heat as an active tracer for aquifer characterization is a topic of increasing interest. In this study, we investigate the potential of using heat tracer tests for characterization of a shallow alluvial aquifer. A thermal tracer test was conducted in the alluvial aquifer of the Meuse River, Belgium. The tracing experiment consisted in simultaneously injecting heated water and a dye tracer in an injection well and monitoring the evolution of groundwater temperature and tracer concentration in the pumping well and in measurement intervals. To get insights in the 3D characteristics of the heat transport mechanisms, temperature data from a large number of observation wells closely spaced along three transects were used. Temperature breakthrough curves in observation wells are contrasted with what would be expected in an ideal layered aquifer. They reveal strongly unequal lateral and vertical components of the transport mechanisms. The observed complex behavior of the heat plume is explained by the groundwater flow gradient on the site and heterogeneities in the hydraulic conductivity field. Moreover, due to high injection temperatures during the field experiment a temperature-induced fluid density effect on heat transport occurred. By using a flow and heat transport numerical model with variable density coupled with a pilot point approach for inversion of the hydraulic conductivity field, the main preferential flow paths were delineated. The successful application of a field heat tracer test at this site suggests that heat tracer tests is a promising approach to image hydraulic conductivity field. This methodology could be applied in aquifer thermal energy storage (ATES) projects for assessing future efficiency that is strongly linked to the hydraulic conductivity variability in the considered aquifer.

Principles and techniques of gamma ray tracers

International Nuclear Information System (INIS)

Claxton, K.T.

1978-01-01

Radioactive tracer techniques provide a very sensitive means of studying physical and chemical processes in a whole variety of different media. Some of the techniques and principles of radioactive tracers and their application to practical engineering systems are discussed. Information which has been found useful in the design of high temperature liquid sodium facilities employing radio-tracers, is presented. The report deals solely with the use of gamma-emitting species as the tracer. These find particular application for in-situ studies on engineering systems where the highly penetrating properties of gamma rays are needed for detection through strongly absorbent media such as stainless steel pepe walls. (author)

Abdominal migraine in childhood: a review

Directory of Open Access Journals (Sweden)

Scicchitano B

2014-08-01

Full Text Available Beatrice Scicchitano,1 Gareth Humphreys,1 Sally G Mitton,2 Thiagarajan Jaiganesh1 1Children's Emergency Department, 2Department of Paediatric Gastroenterology, St Georges Hospital, St Georges Healthcare NHS Trust, Tooting, London, United Kingdom Abstract: The childhood condition of abdominal migraine has been described under many different synonyms, including "abdominal epilepsy", "recurrent abdominal pain", "cyclical vomiting syndrome", and "functional gastrointestinal disorder". In the early literature, abdominal migraine is included in the "childhood periodic syndrome", first described by Wyllie and Schlesinger in 1933. Abdominal migraine has emerged over the last century as a diagnostic entity in its own right thanks to the development of well defined diagnostic criteria and its recent inclusion in the International Headache Society's Classification of Headache disorders. Despite this progress, little is known about the pathophysiology of the condition, and the treatment options are poorly defined. Here we summarize the recent literature, with particular focus on establishing the diagnosis of abdominal migraine and its pathophysiology, and suggest an approach to management. Keywords: abdominal migraine, recurrent abdominal pain, abdominal epilepsy, cyclical vomiting

Abdominal crunch exercise analysis performed with maximum and submaximum loads: An electromyographic study

Directory of Open Access Journals (Sweden)

M.L. Moura

2011-01-01

Full Text Available The purpose of this study was to verify the electromyographic activity of the rectus abdominis and obliquus externus abdominis during abdominal crunch exercise performed with maximum and submaximum loads. Thirteen male and female university students participated in this investigation (18-23 years old. The subjects completed abdominal crunch exercise until exhaustion with 20, 40, 60 and 80% of the maximum load. The root-mean-square (RMS from electromyography activity of the rectus abdominis and obliquus externus muscles from the first and last three repetitions from each workload performed was analyzed. RMS for the last repetitions increased in relation to the first repetitions for the 20% workload, first two repetitions on 40% workload and first repetition on the 80% workload. There was no difference for the 60% workload. Results showed that external load on abdominal crunch exercise might be an alternative to increase intensity while performing abdominal crunch exercise, which on its turn can be a practical tool for subjects that aim to increase abdominal strength level.

Intra-abdominal tuberculous peritonitis

International Nuclear Information System (INIS)

Schneider, G.; Ahlhelm, F.; Altmeyer, K.; Kramann, B.; Hennes, P.; Pueschel, W.; Karadiakos, N.

2001-01-01

We report the case of a 15-year-old boy suffering from progressive dyspnea on exertion and painful abdominal protrusion. Final diagnosis of intra-abdominal tuberculosis (TB), including lymphadenopathy and abdominal abscess formation, was made following elective laparotomy. This type of disease is a rare manifestation of extrapulmonary tuberculosis. The imaging findings in unenhanced and contrast-enhanced MRI and laparoscopic images are presented. Differential diagnosis of abdominal abscess formation and other fungal or bacteriological infections, as well as the imaging findings of this type of lesion, are discussed. This case demonstrates that atypical manifestation of TB may remain unrecognized; thus, awareness of this kind of manifestation of tuberculosis may prevent patients from being subjected to inappropriate therapies. (orig.)

Intra-abdominal tuberculous peritonitis

Energy Technology Data Exchange (ETDEWEB)

Schneider, G.; Ahlhelm, F.; Altmeyer, K.; Kramann, B. [Dept. of Diagnostic Radiology, University Hospital, Homburg (Germany); Hennes, P. [Dept. of Pediatrics, University Hospital, Homburg (Germany); Pueschel, W. [Dept. of Pathology, University Hospital, Homburg (Germany); Karadiakos, N. [Dept. of Pediatric Surgery, University Hospital, Homburg (Germany)

2001-07-01

We report the case of a 15-year-old boy suffering from progressive dyspnea on exertion and painful abdominal protrusion. Final diagnosis of intra-abdominal tuberculosis (TB), including lymphadenopathy and abdominal abscess formation, was made following elective laparotomy. This type of disease is a rare manifestation of extrapulmonary tuberculosis. The imaging findings in unenhanced and contrast-enhanced MRI and laparoscopic images are presented. Differential diagnosis of abdominal abscess formation and other fungal or bacteriological infections, as well as the imaging findings of this type of lesion, are discussed. This case demonstrates that atypical manifestation of TB may remain unrecognized; thus, awareness of this kind of manifestation of tuberculosis may prevent patients from being subjected to inappropriate therapies. (orig.)

Abdominal Compartment Syndrome Secondary to Chronic Constipation

Directory of Open Access Journals (Sweden)

Helene Flageole

2011-01-01

Full Text Available Abdominal compartment syndrome (ACS is defined as an elevated intraabdominal pressure with evidence of organ dysfunction. The majority of published reports of ACS are in neonates with abdominal wall defects and in adults following trauma or burns, but it is poorly described in children. We describe the unusual presentation of an 11-year-old boy with a long history of chronic constipation who developed acute ACS requiring resuscitative measures and emergent disimpaction. He presented with a 2-week history of increasing abdominal pain, nausea, diminished appetite and longstanding encopresis. On exam, he was emaciated with a massively distended abdomen with a palpable fecaloma. Abdominal XR confirmed these findings. Within 24 hours of presentation, he became tachycardic and oliguric with orthostatic hypotension. Following two enemas, he acutely deteriorated with severe hypotension, marked tachycardia, acute respiratory distress, and a declining mental status. Endotracheal intubation, fluid boluses, and vasopressors were commenced, followed by emergent surgical fecal disimpaction. This resulted in rapid improvement in vital signs. He has been thoroughly investigated and no other condition apart from functional constipation has been identified. Although ACS secondary to constipation is extremely unusual, this case illustrates the need to actively treat constipation and what can happen if it is not.

Toxicity of fluorescent tracers and their degradation byproducts

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Philippe Gombert

2017-01-01

Full Text Available Tracer tests are frequently used to delineate catchment area of water supply springs in karstic zones. In the karstic chalk of Normandy, the main tracers used are fluorescent: uranine, sulforhodamine B, naphtionate, and Tinopal®. In this area, a statistical analysis shows that less than half of the injected tracers joins the monitored restitution points and enters the drinking water system where they undergo chlorination. Most of the injected tracers is absorbed in the rock matrix or is thrown out of the aquifer via karstic springs: then it can join superficial waters where it is degraded due to the sun and air action. The paper presents firstly the laboratory degradation of a first batch of fluorescent tracers in contact with chlorine, in order to simulate their passage through a water treatment system for human consumption. A second batch of the same tracers is subjected to agents of natural degradation: ultraviolet illumination, sunlight and air sparging. Most tracers is degraded, and toxicity and ecotoxicity tests (on rats, daphniae and algae are performed on degradation byproducts. These tests do not show any acute toxicity but a low to moderate ecotoxicity. In conclusion, the most used fluorescent tracers of the Normandy karstic chalk and their artificial and natural degradation byproducts do not exhibit significant toxicity to humans and the aquatic environment, at the concentrations generally noted at the restitution points.

Asymmetry of activation of lateral abdominal muscles during the neurodevelopmental traction technique.

Science.gov (United States)

Gogola, Anna; Gnat, Rafał; Zaborowska, Małgorzata; Dziub, Dorota; Gwóźdź, Michalina

2018-01-01

The aim of the study was to evaluate the symmetry and pattern of activation of lateral abdominal muscles (LAM) in response to neurodevelopmental traction technique. Measurements of LAM thickness were performed in four experimental conditions: during traction with the force of 5% body weight (5% traction): 1) in neutral position, 2) in 20° posterior trunk inclination; during traction with the force of 15% body weight (15% traction): 3) in neutral position, 4) in 20° posterior trunk inclination. Thirty-seven healthy children participated in the study. Not applicable. To evaluate LAM activation level ultrasound technology was employed (two Mindray DP660 devices (Mindray, Shenzhen, China) with 75L38EA linear probes). An experiment with repeated measurements of the dependent variables was conducted. Side-to-side LAM activation asymmetry showed relatively high magnitude, however, significant difference was found only in case of the obliquus externus (OE) during stronger traction (P muscle differences were most pronounced between the OE and TrA (P muscles showing less intense activation. In statistical terms, the only signs of side-to-side asymmetry of LAM activation are visible in case of the OE, however, the magnitude of asymmetry is relatively high. The results allow to identify patterns of activation of LAM in children showing typical development that will serve as a reference in future studies in children with neurological disorder. Copyright © 2017 Elsevier Ltd. All rights reserved.

The European Tracer Experiment - experimental results and database

International Nuclear Information System (INIS)

Nodop, K.; Connolly, R.; Girardi, F.

1997-01-01

As part of the European Tracer Experiment (ETEX) two successful atmospheric experiments were carried out in October and November, 1994. Perfluorocarbon (PFC) tracers were released into the atmosphere in Monterfil, Brittany, and air samples were taken at 168 stations in 17 European countries for 72 hours after the release. Upper air tracer measurements were made from three aircraft. During the first experiment a westerly air flow transported the tracer plume north-eastwards across Europe. During the second release the flow was eastwards. The results from the ground sampling network allowed the determination of the cloud evolution as far as Sweden, Poland and Bulgaria. Typical background concentrations of the tracer used are around 5 to 7 fl/l in ambient air. Concentrations in the plume ranged from 10 to above 200 fl/l. The tracer release characteristics, the tracer concentrations at the ground and in upper air, the routine and additional meteorological observations at the ground level and in upper air, trajectories derived from constant-level balloons and the meteorological input fields for long-range transport (LRT) models are assembled in the ETEX database. The ETEX database is accessible via the Internet

Evaluation of abdominal CT in the initial treatment of abdominal trauma

International Nuclear Information System (INIS)

Watanabe, Shinsuke; Ishii, Takashi; Kuwata, Katsuya; Yoneyama, Chihiro; Kitamura, Kazuya; Sasaki, Yoshifumi; Kamachi, Masahiro; Nishiguchi, Hiroyasu.

1986-01-01

During the last four years 102 patients with abdominal trauma were examined by CT for preoperative evaluation in our hospital. In 35 patients (34 %), the CT scans revealed no abnormal findings. They were all managed conservatively except for one case of perforated small bowel. In 67 patients (66 %) CT revealed evidences of substantial abdominal or retroperitoneal trauma. In 30 of them CT findings were confirmed by surgery. Hepatic injury is usually easily recognized by CT. CT is also useful for the detection of renal or splenic injuries. The majority of those parenchymatous organ injuries were successfully managed with conservative therapy, despite apparent traumatic lesions revealed by CT. Repeat CT scans is proved to be very useful to follow the changes of these traumatic lesions. In conclusion, application of abdominal CT is extremely useful for the initial decision making in treatment of patients with abdominal trauma and for the follow-up observation of injured lesions. (author)

Exploring Hydrofluorocarbons as Groundwater Age Tracers (Invited)

Science.gov (United States)

Haase, K. B.; Busenberg, E.; Plummer, L. N.; Casile, G.; Sanford, W. E.

2013-12-01

Groundwater dating tracers are an essential tool for analyzing hydrologic conditions in groundwater systems. Commonly used tracers for dating post-1940's groundwater include sulfur hexafluoride (SF6), chlorofluorocarbons (CFCs), 3H-3He, and other isotopic tracers (85Kr, δ2H and δ18O isotopes, etc.). Each tracer carries a corresponding set of advantages and limitations imposed by field, analytical, and interpretive methods. Increasing the number available tracers is appealing, particularly if they possess inert chemical properties and unique temporal emission histories from other tracers. Atmospherically derived halogenated trace gases continue to hold untapped potential for new tracers, as they are generally inert and their emission histories are well documented. SF5CF3, and CFC-13 were previously shown to have application as dating tracers, though their low mixing ratios and low solubility require large amounts of water to be degassed for their quantification. Two related groups of compounds, hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) are hypothesized to be potential age tracers, having similar mixing ratios to the CFCs and relatively high solubility. However, these compounds yield gas chromatography electron capture detector (GC-ECD) responses that are 10-2 -10-5 less than CFC-12, making purge and trap or field stripping GC-ECD approaches impractical. Therefore, in order to use dissolved HCFCs and HFCs as age tracers, different approaches are needed. To solve this problem, we developed an analytical method that uses an atomic emission detector (GC-AED) in place of an ECD to detect fluorinated compounds. In contrast to the ECD, the AED is a universally sensitive, highly linear, elementally specific detector. The new GC-AED system is being used to measure chlorodifluoromethane (HCFC-22), 1,1,1,2-tetrafluoroethane (HFC-134a), and other fluorinated compounds in one liter water samples to study their potential as age dating tracers. HCFC-22 is a

Abdominal epilepsy

International Nuclear Information System (INIS)

Hasan, N.; Razzaq, A.

2004-01-01

Abdominal epilepsy (AE) is a rather uncommon clinical entity in children that might create diagnostic confusion especially when it lacks the typical manifestations of an epileptic seizure. We report the case of a young boy having apparently unexplained episodes of paroxysmal abdominal symptoms with no other suggestion of an underlying epileptic disorder. The case also explains how the clinical presentation can be misleading unless a high index of suspicion is maintained to reach the ultimate diagnosis. (author)

Abdominal Sepsis.

Science.gov (United States)

De Waele, Jan J

2016-08-01

Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy.

Improving Marine Ecosystem Models with Biochemical Tracers

Science.gov (United States)

Pethybridge, Heidi R.; Choy, C. Anela; Polovina, Jeffrey J.; Fulton, Elizabeth A.

2018-01-01

Empirical data on food web dynamics and predator-prey interactions underpin ecosystem models, which are increasingly used to support strategic management of marine resources. These data have traditionally derived from stomach content analysis, but new and complementary forms of ecological data are increasingly available from biochemical tracer techniques. Extensive opportunities exist to improve the empirical robustness of ecosystem models through the incorporation of biochemical tracer data and derived indices, an area that is rapidly expanding because of advances in analytical developments and sophisticated statistical techniques. Here, we explore the trophic information required by ecosystem model frameworks (species, individual, and size based) and match them to the most commonly used biochemical tracers (bulk tissue and compound-specific stable isotopes, fatty acids, and trace elements). Key quantitative parameters derived from biochemical tracers include estimates of diet composition, niche width, and trophic position. Biochemical tracers also provide powerful insight into the spatial and temporal variability of food web structure and the characterization of dominant basal and microbial food web groups. A major challenge in incorporating biochemical tracer data into ecosystem models is scale and data type mismatches, which can be overcome with greater knowledge exchange and numerical approaches that transform, integrate, and visualize data.

Tracer monitoring of enhanced oil recovery projects

Directory of Open Access Journals (Sweden)

Kleven R.

2013-05-01

Full Text Available In enhanced oil recovery (EOR, chemicals are injected into the oil reservoir, either to increase macroscopic sweep efficiency, or to reduce remaining oil saturation in swept zones. Tracers can be used to identify reservoirs that are specifically suited for EOR operations. Injection of a selection of partitioning tracers, combined with frequent sample analysis of produced fluids, provides information suited for estimation of residual oil saturation. Tracers can also be used to evaluate and optimize the application of EOR chemicals in the reservoir. Suitable tracers will follow the EOR chemicals and assist in evaluation of retention, degradation or trapping. In addition to field applications, tracers also have a large potential as a tool to perform mechanistic studies of EOR chemicals in laboratory experiments. By labelling EOR chemicals with radioactive isotopes of elements such as H, C and S, detailed studies of transport mechanisms can be carried out. Co-injection of labelled compounds in dynamic flooding experiments in porous media will give information about retention or separation of the unique compounds constituting the chemical formulation. Separation of such compounds may be detrimental to obtaining the EOR effect expected. The paper gives new information of specific methods, and discusses current status for use of tracers in EOR operations.

Heat tracer methods

Science.gov (United States)

Healy, Richard W.; Scanlon, Bridget R.

2010-01-01

The flow of heat in the subsurface is closely linked to the movement of water (Ingebritsen et al., 2006). As such, heat has been used as a tracer in groundwater studies for more than 100 years (Anderson, 2005). As with chemical and isotopic tracers (Chapter 7), spatial or temporal trends in surface and subsurface temperatures can be used to infer rates of water movement. Temperature can be measured accurately, economically, at high frequencies, and without the need to obtain water samples, facts that make heat an attractive tracer. Temperature measurements made over space and time can be used to infer rates of recharge from a stream or other surface water body (Lapham, 1989; Stonestrom and Constantz, 2003); measurements can also be used to estimate rates of steady drainage through depth intervals within thick unsaturated zones (Constantz et al., 2003; Shan and Bodvarsson, 2004). Several thorough reviews of heat as a tracer in hydrologic studies have recently been published (Constantz et al., 2003; Stonestrom and Constantz, 2003; Anderson, 2005; Blasch et al., 2007; Constantz et al., 2008). This chapter summarizes heat-tracer approaches that have been used to estimate recharge.Some clarification in terminology is presented here to avoid confusion in descriptions of the various approaches that follow. Diffuse recharge is that which occurs more or less uniformly across large areas in response to precipitation, infiltration, and drainage through the unsaturated zone. Estimates of diffuse recharge determined using measured temperatures in the unsaturated zone are referred to as potential recharge because it is possible that not all of the water moving through the unsaturated zone will recharge the aquifer; some may be lost to the atmosphere by evaporation or plant transpiration. Estimated fluxes across confining units in the saturated zone are referred to as interaquifer flow (Chapter 1). Focused recharge is that which occurs directly from a point or line source, such

Left ventricular function impairment in patients with normal-weight obesity: contribution of abdominal fat deposition, profibrotic state, reduced insulin sensitivity, and proinflammatory activation.

Science.gov (United States)

Kosmala, Wojciech; Jedrzejuk, Diana; Derzhko, Roksolana; Przewlocka-Kosmala, Monika; Mysiak, Andrzej; Bednarek-Tupikowska, Grazyna

2012-05-01

Obesity predisposes to left ventricular (LV) dysfunction and heart failure; however, the risk of these complications has not been assessed in patients with a normal body mass index (BMI) but increased body fat content (normal-weight obesity, NWO). We hypothesized that LV performance in NWO may be impaired and sought to investigate potential contributors to cardiac functional abnormalities. One hundred sixty-eight subjects (age, 38±7 years) with BMI affecting the myocardium were classified on the basis of body fat content into 2 groups: with NWO and without NWO. Echocardiographic indices of LV systolic and diastolic function, including myocardial velocities and deformation, serological fibrosis markers, indicators of proinflammatory activation, and metabolic control, were evaluated. Subjects with NWO demonstrated impaired LV systolic and diastolic function, increased fibrosis intensity (assessed by procollagen type I carboxy-terminal propeptide [PICP]), impaired insulin sensitivity, and increased proinflammatory activation as compared with individuals with normal body fat. The independent correlates of LV systolic and diastolic function variables were as follows: for strain, IL-18 (β=-0.17, P<0.006), C-reactive protein (β=-0.20, P<0.002) and abdominal fat deposit (β=-0.20, P<0.003); for tissue S velocity, PICP (β=-0.21, P<0.002) and abdominal fat deposit (β=-0.43, P<0.0001); for tissue E velocity, abdominal fat deposit (β=-0.30, P<0.0001), PICP (β=-0.31, P<0.0001) and homeostasis model assessment of insulin resistance index (HOMA IR; β=-0.20, P<0.002); and for E/e'-PICP, IL-18 (both β=0.18, P<0.01) and HOMA IR (β=0.16, P<0.04). In patients with NWO, subclinical disturbances of LV function are independently associated with the extent of abdominal fat deposit, profibrotic state (as reflected by circulating PICP), reduced insulin sensitivity, and proinflammatory activation.

Abdominal wall hernias: computed tomography findings

International Nuclear Information System (INIS)

D'Ippolito, Giuseppe; Rosas, George de Queiroz; Mota, Marcos Alexandre; Akisue, Sandra R. Tsukada; Galvao Filho, Mario de Melo.

2005-01-01

Abdominal hernias are a common clinical problem Clinical diagnosis of abdominal hernias can sometimes be challenging, particularly in obese patients or patients with previous abdominal surgery. CT scan of the abdomen allows visualization of hernias and their contents and the differentiation from other masses of the abdominal wall such as tumors, hematomas and abscesses. Moreover, CT may identify complications such as incarceration, bowel obstruction, volvulus and strangulation. This study illustrates the CT scan findings observed in different types of abdominal wall hernias. (author)

Da Vinci-assisted abdominal cerclage.

Science.gov (United States)

Barmat, Larry; Glaser, Gretchen; Davis, George; Craparo, Frank

2007-11-01

To report the first placement of an abdominal cervicoisthmic cerclage using the da Vinci robot. Case report. Tertiary-care hospital. A 39-year-old female with a history of cervical insufficiency who required a cerclage and was not a candidate for transvaginal cerclage placement. Abdominal cervicoisthmic cerclage placement using the da Vinci robot. Ability to safely and successfully place an abdominal cerclage using the da Vinci robot. Abdominal cerclage was successfully placed using the da Vinci robot. The patient had minimal blood loss and was discharged to home on the same day as surgery. Da Vinci robot-assisted abdominal cerclage placement is an innovative application of robotic surgery and may alter the standard of care for women who require this surgery.

Radiochemical tracers in marine biology

International Nuclear Information System (INIS)

Petrocelli, S.R.; Anderson, J.W.; Neff, J.M.

1977-01-01

Tracers have been used in a great variety of experimentation. More recently, labeled materials have been applied in marine biological research. Some of the existing tracer techniques have been utilized directly, while others have been modified to suit the specific needs of marine biologists. This chapter describes some of the uses of tracers in marine biological research. It also mentions the problems encountered as well as offering possible solutions and discusses further applications of these techniques. Only pertinent references are cited and additional information may be obtained by consulting these references. Due to their relative ease of maintenance, freshwater species are also utilized in studies which involve radiotracer techniques. Since most of these techniques e directly applicable to marine species, some of these studies will also be included

Plutonium and tracer particle resuspension: an overview of selected Battelle-Northwest experiments

International Nuclear Information System (INIS)

Sehmel, G.A.

1977-01-01

Plutonium resuspension at Rocky Flats was determined in July 1973, by measuring airborne plutonium as a function of sampling height and of wind speed. The maximum airborne plutonium-239 concentration was 3700 aCi/m 3 . The maximum plutonium-239 activity per gram of collected airborne soil was 50 pCi/g. Airborne plutonium concentrations were shown to increase as the sixth power of wind speed, but the data were very imprecise. In measurement of fallout resuspension caused by burning vegetation, the 137 Cs concentration in a forest fire smoke plume was 22 times the concentration in ambient air. Resuspension rates for a man walking across a tracer area on an asphalt surface ranged from 1 x 10 -5 to 7 x 10 -4 fraction of tracer resuspended/pass. For vehicular traffic driven on a tracer lane, resuspension rates from the asphalt surface ranged from 10 -4 to 10 -2 fraction resuspended/pass. When the vehicle was driven on the lane adjacent to the tracer lane, resuspension rates were smaller, ranging from 10 -5 to 10 -3 fraction resuspended/pass. Resuspension rates decreased when the tracer had been on the ground for several days. In comparison to the asphalt surface, vehicle-caused tracer resuspension rates from a cheat grass area were lower, ranging from 10 -5 to 10 -4 fraction resuspended/pass. Wind caused tracer resuspension rates were on the order of 10 -11 fraction resuspended/sec for nonrespirable particles. Resuspension rates for respirable particles increased as the 4.8th power of wind speed, ranging from 10 -11 to 10 -7 fraction resuspended/sec. In another study, airborne respirable soil concentrations measured as a function of wind speed increased as the 0.6 to 3.2 power of wind speed

Instantaneous axial velocity of a radioactive tracer determined with radioactive particle tracking

Energy Technology Data Exchange (ETDEWEB)

Fraguio, Maria Sol; Cassanello, Miryan C., E-mail: miryan@di.fcen.uba.a [Universidad de Buenos Aires (Argentina). Facultad de Ciencias Exactas y Naturales. Programa de Investigacion y Desarrollo de Fuentes Alternativas de Materias Primas y Energia (PINMATE); Cardona, Maria Angelica; Hojman, Daniel, E-mail: cardona@tandar.cnea.gov.a [CONICET, Buenos Aires (Argentina); Somacal, Hector [Comision Nacional de Energia Atomica (CNEA), Buenos Aires (Argentina). Centro Atomico Constituyentes. Dept. de Fisica

2009-07-01

Radioactive Particle Tracking (RPT) is a technique that has been successfully used to get features of the liquid and/or the solid motion in multiphase contactors. It is one of the rare techniques able to provide experimental data in dense and strongly turbulent multiphase media. Validation of the technique has always been based on comparing the estimated mean velocity to an imposed mean velocity although the extracted features are frequently related to the instantaneous velocities. The present work pursues the analysis, through calibration experiments, of the ability of RPT to get the actual tracer instantaneous velocities. With this purpose, the motion of a radioactive tracer attached to a moving rod driven by a pneumatic system is reconstructed from the combined response of an array of 10 NaI(Tl) scintillation detectors. Simultaneously, the tracer motion is registered through an encoder able to establish the axial tracer coordinate with high precision and high time resolution. The tracer is a gold particle, activated by neutron bombardment. The rod is moved at different velocities and it travels upwards and downwards close to the column centre. A mini-pilot scale bubble column is used as the test facility. The model liquid is tap water in batch mode and the gas is air, flowing at different gas velocities, spanning the homogeneous and the heterogeneous flow regimes. Time series of the entirety response of all the detectors, while the rod is moving at different imposed velocities within the two phase emulsion, are measured with a sampling period of 0.03 s during about 2 minutes. The instantaneous tracer positions and velocities reconstructed from RPT and the one obtained from the encoder response are compared under different operating conditions and for different tracer velocities. (author)

Functional abdominal pain.

Science.gov (United States)

Grover, Madhusudan; Drossman, Douglas A

2010-10-01

Functional abdominal pain syndrome (FAPS) is a relatively less common functional gastrointestinal (GI) disorder defined by the presence of constant or frequently recurring abdominal pain that is not associated with eating, change in bowel habits, or menstrual periods (Drossman Gastroenterology 130:1377-1390, 2006), which points to a more centrally targeted (spinal and supraspinal) basis for the symptoms. However, FAPS is frequently confused with irritable bowel syndrome and other functional GI disorders in which abdominal pain is associated with eating and bowel movements. FAPS also differs from chronic abdominal pain associated with entities such as chronic pancreatitis or chronic inflammatory bowel disease, in which the pain is associated with peripherally acting factors (eg, gut inflammation or injury). Given the central contribution to the pain experience, concomitant psychosocial disturbances are common and strongly influence the clinical expression of FAPS, which also by definition is associated with loss of daily functioning. These factors make it critical to use a biopsychosocial construct to understand and manage FAPS, because gut-directed treatments are usually not successful in managing this condition.

A survey of HC₃N in extragalactic sources - is HC₃N a tracer of activity in ULIRGs?

DEFF Research Database (Denmark)

Lindberg, Johan; Aalto, S.; Costagliola, F.

2011-01-01

, and to compare HC3N with other molecular tracers (HCN, HNC), as well as other properties (silicate absorption strength, IR flux density ratios, C II flux, and megamaser activity). Methods. We present mm IRAM 30 m, OSO 20 m, and SEST observations of HC3N rotational lines (mainly the J = 10-9 transition...

Rate equations for tracer studies in recirculating reactors

Energy Technology Data Exchange (ETDEWEB)

Happel, J [Columbia Univ., New York (USA). Dept. of Chemical Engineering

1974-10-01

The employment of isotopic tracers is a useful technique for gaining insight into the rate controlling steps of a complex chemical reaction such as is frequently encountered in heterogeneous catalysis. An effective procedure has been to superpose tracer transfer on a reaction which is occurring under steady state conditions. If tracer transfer is employed in this fashion it is often possible to assess the individual step velocities in an assumed reaction mechanism. If transient transfer of tracer is now introduced it is possible in addition to estimate surface concentrations of chemisorbed species. The purpose of the present paper is to present the mathematical relationships involved when transfer of the tracer is not differential in the investigation. For this purpose a simple example is chosen to illustrate the various possibilities involved.

Rate equations for tracer studies in recirculatinng reactors

International Nuclear Information System (INIS)

Happel, J.

1974-01-01

The employment of isotopic tracers is a useful technique for gaining insight into the rate controlling steps of a complex chemical reaction such as is frequently encountered in heterogeneous catalysis. An effective procedure has been to superpose tracer transfer on a reaction which is occurring under steady state conditions. If tracer transfer is employed in this fashion it is often possible to assess the individual step velocities in an assumed reaction mechanism. If transient transfer of tracer is now introduced it is possible in addition to estimate surface concentrations of chemisorbed species. The purpose of the present paper is to present the mathematical relationships involved when transfer of the tracer is not differential in the investigation. For this purpose a simple example is chosen to illustrate the various possibilities involved. (auth.)

Childhood abdominal cystic lymphangioma

International Nuclear Information System (INIS)

Konen, Osnat; Rathaus, Valeria; Shapiro, Myra; Dlugy, Elena; Freud, Enrique; Kessler, Ada; Horev, Gadi

2002-01-01

Background: Abdominal lymphangioma is a rare benign congenital malformation of the mesenteric and/or retroperitoneal lymphatics. Clinical presentation is variable and may be misleading; therefore, complex imaging studies are necessary in the evaluation of this condition. US and CT have a major role in the correct preoperative diagnosis and provide important information regarding location, size, adjacent organ involvement, and expected complications. Objective: To evaluate the clinical and imaging findings of seven children with proven abdominal cystic lymphangioma. Materials and methods: Clinical and imaging files of seven children with pathologically proven abdominal lymphangioma, from three university hospitals, were retrospectively evaluated. Patient's ages ranged from 1 day to 6 years (mean, 2.2 years). Symptoms and signs included evidence of inflammation, abnormal prenatal US findings, chronic abdominal pain, haemorrhage following trauma, clinical signs of intestinal obstruction, and abdominal distension with lower extremities lymphoedema. Plain films of five patients, US of six patients and CT of five patients were reviewed. Sequential imaging examinations were available in two cases. Results: Abdominal plain films showed displacement of bowel loops by a soft tissue mass in five of six patients, two of them with dilatation of small bowel loops. US revealed an abdominal multiloculated septated cystic mass in five of six cases and a single pelvic cyst in one which changed in appearance over 2 months. Ascites was present in three cases. CT demonstrated a septated cystic mass of variable sizes in all available five cases. Sequential US and CT examinations in two patients showed progressive enlargement of the masses, increase of fluid echogenicity, and thickening of walls or septa in both cases, with multiplication of septa in one case. At surgery, mesenteric lymphangioma was found in five patients and retroperitoneal lymphangioma in the other two. Conclusions: US

Childhood abdominal cystic lymphangioma

Energy Technology Data Exchange (ETDEWEB)

Konen, Osnat; Rathaus, Valeria; Shapiro, Myra [Department of Diagnostic Imaging, Meir General Hospital, Sapir Medical Centre, Kfar Saba (Israel); Dlugy, Elena [Department of Paediatric Surgery, Schneider Medical Centre, Sackler School of Medicine, Tel-Aviv University (Israel); Freud, Enrique [Department of Paediatric Surgery, Sapir Medical Centre, Sackler School of Medicine, Tel-Aviv University (Israel); Kessler, Ada [Department of Diagnostic Imaging, Sourasky Medical Centre, Tel-Aviv (Israel); Horev, Gadi [Department of Diagnostic Imaging, Schneider Medical Centre, Tel-Aviv (Israel)

2002-02-01

Background: Abdominal lymphangioma is a rare benign congenital malformation of the mesenteric and/or retroperitoneal lymphatics. Clinical presentation is variable and may be misleading; therefore, complex imaging studies are necessary in the evaluation of this condition. US and CT have a major role in the correct preoperative diagnosis and provide important information regarding location, size, adjacent organ involvement, and expected complications. Objective: To evaluate the clinical and imaging findings of seven children with proven abdominal cystic lymphangioma. Materials and methods: Clinical and imaging files of seven children with pathologically proven abdominal lymphangioma, from three university hospitals, were retrospectively evaluated. Patient's ages ranged from 1 day to 6 years (mean, 2.2 years). Symptoms and signs included evidence of inflammation, abnormal prenatal US findings, chronic abdominal pain, haemorrhage following trauma, clinical signs of intestinal obstruction, and abdominal distension with lower extremities lymphoedema. Plain films of five patients, US of six patients and CT of five patients were reviewed. Sequential imaging examinations were available in two cases. Results: Abdominal plain films showed displacement of bowel loops by a soft tissue mass in five of six patients, two of them with dilatation of small bowel loops. US revealed an abdominal multiloculated septated cystic mass in five of six cases and a single pelvic cyst in one which changed in appearance over 2 months. Ascites was present in three cases. CT demonstrated a septated cystic mass of variable sizes in all available five cases. Sequential US and CT examinations in two patients showed progressive enlargement of the masses, increase of fluid echogenicity, and thickening of walls or septa in both cases, with multiplication of septa in one case. At surgery, mesenteric lymphangioma was found in five patients and retroperitoneal lymphangioma in the other two

Tracer Testing for Estimating Heat Transfer Area in Fractured Reservoirs

Energy Technology Data Exchange (ETDEWEB)

Pruess, Karsten; van Heel, Ton; Shan, Chao

2004-05-12

A key parameter governing the performance and life-time of a Hot Fractured Rock (HFR) reservoir is the effective heat transfer area between the fracture network and the matrix rock. We report on numerical modeling studies into the feasibility of using tracer tests for estimating heat transfer area. More specifically, we discuss simulation results of a new HFR characterization method which uses surface-sorbing tracers for which the adsorbed tracer mass is proportional to the fracture surface area per unit volume. Sorption in the rock matrix is treated with the conventional formulation in which tracer adsorption is volume-based. A slug of solute tracer migrating along a fracture is subject to diffusion across the fracture walls into the adjacent rock matrix. Such diffusion removes some of the tracer from the fluid in the fractures, reducing and retarding the peak in the breakthrough curve (BTC) of the tracer. After the slug has passed the concentration gradient reverses, causing back-diffusion from the rock matrix into the fracture, and giving rise to a long tail in the BTC of the solute. These effects become stronger for larger fracture-matrix interface area, potentially providing a means for estimating this area. Previous field tests and modeling studies have demonstrated characteristic tailing in BTCs for volatile tracers in vapor-dominated reservoirs. Simulated BTCs for solute tracers in single-phase liquid systems show much weaker tails, as would be expected because diffusivities are much smaller in the aqueous than in the gas phase, by a factor of order 1000. A much stronger signal of fracture-matrix interaction can be obtained when sorbing tracers are used. We have performed simulation studies of surface-sorbing tracers by implementing a model in which the adsorbed tracer mass is assumed proportional to the fracture-matrix surface area per unit volume. The results show that sorbing tracers generate stronger tails in BTCs, corresponding to an effective

An investigation of the reproducibility of ultrasound measures of abdominal muscle activation in patients with chronic non-specific low back pain

Science.gov (United States)

Maher, Chris G.; Latimer, Jane; Hodges, Paul W.; Shirley, Debra

2009-01-01

Ultrasound (US) measures are used by clinicians and researchers to evaluate improvements in activity of the abdominal muscles in patients with low back pain. Studies evaluating the reproducibility of these US measures provide some information; however, little is known about the reproducibility of these US measures over time in patients with low back pain. The objectives of this study were to estimate the reproducibility of ultrasound measurements of automatic activation of the lateral abdominal wall muscles using a leg force task in patients with chronic low back pain. Thirty-five participants from an existing randomised, blinded, placebo-controlled trial participated in the study. A reproducibility analysis was undertaken from all patients using data collected at baseline and after treatment. The reproducibility of measurements of thickness, muscle activation (thickness changes) and muscle improvement/deterioration after intervention (differences in thickness changes from single images made before and after treatment) was analysed. The reproducibility of static images (thickness) was excellent (ICC2,1 = 0.97, 95% CI = 0.96–0.97, standard error of the measurement (SEM) = 0.04 cm, smallest detectable change (SDC) = 0.11 cm), the reproducibility of thickness changes was moderate (ICC2,1 = 0.72, 95% CI 0.65–0.76, SEM = 15%, SDC 41%), while the reproducibility of differences in thickness changes from single images with statistical adjustment for duplicate measures was poor (ICC2,1 = 0.44, 95% CI 0.33–0.58, SEM = 21%, SDC = 66.5%). Improvements in the testing protocol must be performed in order to enhance reproducibility of US as an outcome measure for abdominal muscle activation. PMID:19415347

Inter-observer agreement for abdominal CT in unselected patients with acute abdominal pain

International Nuclear Information System (INIS)

Randen, Adrienne van; Lameris, Wytze; Nio, C.Y.; Spijkerboer, Anje M.; Meier, Mark A.; Tutein Nolthenius, Charlotte; Smithuis, Frank; Stoker, Jaap; Bossuyt, Patrick M.; Boermeester, Marja A.

2009-01-01

The level of inter-observer agreement of abdominal computed tomography (CT) in unselected patients presenting with acute abdominal pain at the Emergency Department (ED) was evaluated. Two hundred consecutive patients with acute abdominal pain were prospectively included. Multi-slice CT was performed in all patients with intravenous contrast medium only. Three radiologists independently read all CT examinations. They recorded specific radiological features and a final diagnosis on a case record form. We calculated the proportion of agreement and kappa values, for overall, urgent and frequently occurring diagnoses. The mean age of the evaluated patients was 46 years (range 19-94), of which 54% were women. Overall agreement on diagnoses was good, with a median kappa of 0.66. Kappa values for specific urgent diagnoses were excellent, with median kappa values of 0.84, 0.90 and 0.81, for appendicitis, diverticulitis and bowel obstruction, respectively. Abdominal CT has good inter-observer agreement in unselected patients with acute abdominal pain at the ED, with excellent agreement for specific urgent diagnoses as diverticulitis and appendicitis. (orig.)

Inter-observer agreement for abdominal CT in unselected patients with acute abdominal pain

Energy Technology Data Exchange (ETDEWEB)

Randen, Adrienne van [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); Academic Medical Center, Amsterdam (Netherlands); Lameris, Wytze [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); Nio, C.Y.; Spijkerboer, Anje M.; Meier, Mark A.; Tutein Nolthenius, Charlotte; Smithuis, Frank; Stoker, Jaap [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Bossuyt, Patrick M. [University of Amsterdam, Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Center, Amsterdam (Netherlands); Boermeester, Marja A. [University of Amsterdam, Department of Surgery, Academic Medical Center, Amsterdam (Netherlands)

2009-06-15

The level of inter-observer agreement of abdominal computed tomography (CT) in unselected patients presenting with acute abdominal pain at the Emergency Department (ED) was evaluated. Two hundred consecutive patients with acute abdominal pain were prospectively included. Multi-slice CT was performed in all patients with intravenous contrast medium only. Three radiologists independently read all CT examinations. They recorded specific radiological features and a final diagnosis on a case record form. We calculated the proportion of agreement and kappa values, for overall, urgent and frequently occurring diagnoses. The mean age of the evaluated patients was 46 years (range 19-94), of which 54% were women. Overall agreement on diagnoses was good, with a median kappa of 0.66. Kappa values for specific urgent diagnoses were excellent, with median kappa values of 0.84, 0.90 and 0.81, for appendicitis, diverticulitis and bowel obstruction, respectively. Abdominal CT has good inter-observer agreement in unselected patients with acute abdominal pain at the ED, with excellent agreement for specific urgent diagnoses as diverticulitis and appendicitis. (orig.)

Lanthanide-based fluorescent tracers in complex media

International Nuclear Information System (INIS)

Brichart, Thomas

2014-01-01

Tracers are objects allowing the determination of the position or the distribution of a product; tracers are currently used in a great variety of domains. Despite the fact that each field has it's own specifications, it is possible to find tracers in medicine (contrast agents), anti-counterfeiting or geological exploration. We have developed lanthanide complex tracers for oil field injection waters. Those tracers, derived from the DOTA, have been detected at concentration lower than 1 ppb, thanks to a simple and compact apparatus. This detection has been made possible by the use of time-resolved fluorescence spectroscopy, this technique allows us to get rid of the background noise created by the intrinsic fluorescence of oil residues that are present in production waters. We also demonstrated how we can, through a reverse microemulsion synthesis, encapsulate several different dyes inside a single nanoparticle composed of a gold core and a silica shell. We showed as well, how those particles can be used as smart tracers to gather data, such as temperature, pH, solvents, etc. inside the well. Finally the use of lanthanides and scale inhibitors properties allowed us to create a simple and fast dosing protocol of such scale inhibitors in injection waters. This dosage will then allow the quick adjustment of their concentration inside each well. (author) [fr

Dose-ranging pilot randomized trial of amino acid mixture combined with physical activity promotion for reducing abdominal fat in overweight adults

Directory of Open Access Journals (Sweden)

Sasai H

2017-07-01

Full Text Available Hiroyuki Sasai,1–3,* Keisuke Ueda,4,5,* Takehiko Tsujimoto,6,7 Hiroyuki Kobayashi,1 Chiaki Sanbongi,4 Shuji Ikegami,4 Yoshio Nakata1 1Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 2Japan Society for the Promotion of Science, Chiyoda, Tokyo, 3Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro, Tokyo, 4Food Science Research Laboratories, Meiji Co., Ltd., Odawara, Kanagawa, 5Graduate School of Comprehensive Human Sciences, 6Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Ibaraki, 7Faculty of Human Sciences, Shimane University, Matsue, Shimane, Japan *These authors contributed equally to this work Objective: The objective of this study was to determine the effective dose of an amino acid mixture comprising arginine, alanine, and phenylalanine combined with physical activity promotion in reducing abdominal fat among overweight adults.Methods: A 12-week randomized, double-blind, placebo-controlled, dose-ranging, pilot trial was conducted in Mito, Japan, from January through April 2016, and the data were analyzed from May through November 2016. The study participants were 35 overweight adults, aged 20–64 years, with no regular exercise habit. Participants were randomly assigned to high-dose (3,000 mg/d, n=9, medium-dose (1,500 mg/d, n=9, low-dose (750 mg/d, n=8, or placebo (0 mg/d, n=9 groups, and the test beverage containing the amino acid mixture or placebo was administered for 12 weeks. All participants maintained a physically active lifestyle during the study period through monthly physical activity promotion sessions and smartphone-based self-monitoring with wearable trackers. Primary outcomes were changes in abdominal total, subcutaneous, and visceral fat areas, assessed by computed tomography.Results: Of the 35 enrolled participants, 32 completed the 12-week follow-up visit. The intention-to-treat analysis revealed that the changes in abdominal total fat

Laparoscopic management of abdominal cocoon

Directory of Open Access Journals (Sweden)

Makam Ramesh

2008-01-01

Full Text Available "Peritonitis fibrosa incapsulata", first described in 1907, is a condition characterized by encasement of the bowel with a thick fibrous membrane. This condition was renamed as "abdominal cocoon" in 1978. It presents as small bowel obstruction clinically. 35 cases of abdominal cocoon have been reported in the literature over the last three decades. Abdominal cocoon is more common in adolescent girls from tropical countries. Various etiologies have been described, including tubercular. It is treated surgically by releasing the entrapped bowel. We report a laparoscopic experience of tubercular abdominal cocoon and review the literature.

Abdominal Aortic Aneurysm (AAA)

Science.gov (United States)

... Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis or plaque buildup causes the ... weak and bulge outward like a balloon. An AAA develops slowly over time and has few noticeable ...

Abdominal emergencies in pediatrics.

Science.gov (United States)

Coca Robinot, D; Liébana de Rojas, C; Aguirre Pascual, E

2016-05-01

Abdominal symptoms are among the most common reasons for pediatric emergency department visits, and abdominal pain is the most frequently reported symptom. Thorough history taking and physical examination can often reach the correct diagnosis. Knowing the abdominal conditions that are most common in each age group can help radiologists narrow the differential diagnosis. When imaging tests are indicated, ultrasonography is usually the first-line technique, enabling the diagnosis or adding relevant information with the well-known advantages of this technique. Nowadays, plain-film X-ray studies are reserved for cases in which perforation, bowel obstruction, or foreign body ingestion is suspected. It is also important to remember that abdominal pain can also occur secondary to basal pneumonia. CT is reserved for specific indications and in individual cases, for example, in patients with high clinical suspicion of abdominal disease and inconclusive findings at ultrasonography. We review some of the most common conditions in pediatric emergencies, the different imaging tests indicated in each case, and the imaging signs in each condition. Copyright © 2016 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

Vitamin B 12 absorption: correction of intestinal retention by whole-body profile activity of vitamin B 12-58 cobalt and by double tracer technique

International Nuclear Information System (INIS)

Goncalves, M.R. Bencke; Gheldof, R.; Paternot, L. van Tricht; Delmotte, E.; Verschaeren, A.; Martin, P.; Verhas, M.; Universidade Federal, Rio de Janeiro, RJ

1997-01-01

Full text. Intestinal retention could give false negative results in determining the whole-body retention of vitamin B 12 absorption (WBC B12-58Co). After having validate the WBC B12-58Co, taking the Schilling test as reference, we have studied the feasibility to evaluate the intestinal contamination by measurement of the profile activity distribution of vitamin B12-58Co and by a double tracer technique (WBC B12-58Co/ WBC 51 Cr Cl3). Methodology: twenty five patients were studied for the setting up of the new methodology. For eleven of them the WBC B12-58 Co retention was measured at the 7th day after the oral administration of 37KBq of B12-58Co using a four detectors whole body counter. One week later, a Schilling test was performed after the oral absorption of 18,5 KBq B12-57Co. Results were expressed as %ID. In these patients, one single peak of hepatic activity was observed on the whole body profile and thus no further intestinal correction was needed. In order to evaluate the intestinal contribution, we made in nine other patients the profile of the whole body distribution of activity at 1 h, 1 week and two weeks after the oral administration of B12-58Co. For five other patients a double tracer technique was used for intestinal correction after the simultaneous oral administration of 37 KBq of B12-58Co and 1,85 MBq of 51 Cr Cl3. The B12-58Co absorption was evaluated after intestinal correction based on subtraction of the 51Cr Cl3 contribution after the formula: B12-58Co(%ID) = WBC B12-58Co - WBC 51 Cr Cl3/1 - WBC 51 Cr Cl3. Results: the correlation with the Schilling test was found excellent: r=0,94 (n=11). The normality for WBC retention (n=7) was define as 53,2 +-12,4% ID (SD). For nine patients studied at the 7th day, the presence of a double peak (hepatic and intestinal peaks) allowed the subtraction by exponential extrapolation; the correction range was 4,4% to 37,2%. With the exception of one observation there was no difference in the measure of vitamin

Continuous administration of short-lived radioisotope tracers and the analogous Laplace transform

International Nuclear Information System (INIS)

Orr, J.S.

1979-01-01

Short-lived radioactive tracers are used because of the low radiation dose to patients. Another advantage finding increasing use, however, is that the equilibrium activities achieved by continuous administration to a steady state contain kinetic information. This is not the case with long-lived isotopes. The derivation of quantitative kinetic information in the form of rate constants or flows requires the formulation of a model of the system being studied. Several approaches to this have been published based on a model of single compartments with simultaneous arrival of tracer. To deal with more realistic models a method is proposed which uses the analogy between the procedure of continuous administration of short-lived tracer and the Laplace transform. This analogy permits all the theorems of Laplace transform theory to be applied to the analysis of measured activities. The basis of the analogy is explained and examples are given of its application to a number of models which represent actual physiology more realistically than single compartment models. In these applications the transformed equations representing the model, with measured values of activity inserted for each transform, are solved to derive the rate constants. This is different from the use of Laplace transforms where the constant coefficients are known and the initial value problem is solved to find the behaviour of the variables. (author)

Abdominal tuberculosis: Imaging features

International Nuclear Information System (INIS)

Pereira, Jose M.; Madureira, Antonio J.; Vieira, Alberto; Ramos, Isabel

2005-01-01

Radiological findings of abdominal tuberculosis can mimic those of many different diseases. A high level of suspicion is required, especially in high-risk population. In this article, we will describe barium studies, ultrasound (US) and computed tomography (CT) findings of abdominal tuberculosis (TB), with emphasis in the latest. We will illustrate CT findings that can help in the diagnosis of abdominal tuberculosis and describe imaging features that differentiate it from other inflammatory and neoplastic diseases, particularly lymphoma and Crohn's disease. As tuberculosis can affect any organ in the abdomen, emphasis is placed to ileocecal involvement, lymphadenopathy, peritonitis and solid organ disease (liver, spleen and pancreas). A positive culture or hystologic analysis of biopsy is still required in many patients for definitive diagnosis. Learning objectives:1.To review the relevant pathophysiology of abdominal tuberculosis. 2.Illustrate CT findings that can help in the diagnosis

Industrial tracer application in people's republic of china

International Nuclear Information System (INIS)

Sun Maoyi

1987-01-01

A number of important applications of radioisotopes and their compounds used as tracers in petroleum industry, metallurgical industry, mechanical industry, chemical industry, electronic industry, hydrology and water conservancy in China are introduced in this paper. And the tracer technique applied to entomology is also mentioned. The industrial tracer applications are successful and beneficial in People's Republic of China from the examples given. (author)

Contributions to hydrological tracer methods and their application

International Nuclear Information System (INIS)

1982-04-01

The activities of the Institut fuer Radiohydrometrie of the GSF are mainly devoted to the field of environmental research studying the quality, use and protection from pollution of drinking water which has become scarce in many parts of the world. The knowledge and experience of a variety of scientific disciplines are combined to the common task of developing new tracer methods and selecting suitable hydrogeological methods to allow quantitative studies of the hydrological cycle, from rainfall to surface or sub-surface run-off. The tracers used in these studies are for the most part stable, natural radioisotopes occurring in the hydrological cycle, as well as fluorescent dyes or radionuclides for water labelling. The contributions collected in this volume are grouped according to the above outline of tasks and present a survey of current methods and measurements, illustrating their efficiency in solving hydrological problems. (orig./RW) [de

Tracer Methods for Characterizing Fracture Creation in Engineered Geothermal Systems

Energy Technology Data Exchange (ETDEWEB)

Rose, Peter [Energy & Geoscience Institute at the University of Utah, Salt Lake City, UT (United States); Harris, Joel [Univ. of Utah, Salt Lake City, UT (United States)

2014-05-08

The aim of this proposal is to develop, through novel high-temperature-tracing approaches, three technologies for characterizing fracture creation within Engineered Geothermal Systems (EGS). The objective of a first task is to identify, develop and demonstrate adsorbing tracers for characterizing interwell reservoir-rock surface areas and fracture spacing. The objective of a second task is to develop and demonstrate a methodology for measuring fracture surface areas adjacent to single wells. The objective of a third task is to design, fabricate and test an instrument that makes use of tracers for measuring fluid flow between newly created fractures and wellbores. In one method of deployment, it will be used to identify qualitatively which fractures were activated during a hydraulic stimulation experiment. In a second method of deployment, it will serve to measure quantitatively the rate of fluid flowing from one or more activated fracture during a production test following a hydraulic stimulation.

Journal: A Review of Some Tracer-Test Design Equations for ...

Science.gov (United States)

Determination of necessary tracer mass, initial sample-collection time, and subsequent sample-collection frequency are the three most difficult aspects to estimate for a proposed tracer test prior to conducting the tracer test. To facilitate tracer-mass estimation, 33 mass-estimation equations are reviewed here, 32 of which were evaluated using previously published tracer-test design examination parameters. Comparison of the results produced a wide range of estimated tracer mass, but no means is available by which one equation may be reasonably selected over the others. Each equation produces a simple approximation for tracer mass. Most of the equations are based primarily on estimates or measurements of discharge, transport distance, and suspected transport times. Although the basic field parameters commonly employed are appropriate for estimating tracer mass, the 33 equations are problematic in that they were all probably based on the original developers' experience in a particular field area and not necessarily on measured hydraulic parameters or solute-transport theory. Suggested sampling frequencies are typically based primarily on probable transport distance, but with little regard to expected travel times. This too is problematic in that tends to result in false negatives or data aliasing. Simulations from the recently developed efficient hydrologic tracer-test design methodology (EHTD) were compared with those obtained from 32 of the 33 published tracer-

Tracer tests Wairakei

International Nuclear Information System (INIS)

McCabe, W.J.; Manning, M.R.; Barry, B.J.

1980-07-01

The report summarises the radioactive tracer tests, using iodine-131 and bromine-82, made in the Wairakei geothermal field over the period 1978-80. Injection of tracer into three wells with strong cool water downflows at about 300-400m below ground level, produced strong rapid responses from the only deep wells feeding from about 800-1000m and lying in the south-westerly direction from the injection wells, i.e. parallel to the fault planes. Shallower wells, even though in some cases much closer to the injection well, reacted much more slowly. Velocities, as measured by peak arrival times, as high as 22m/h over 200m and 11m/h over 650m, were found. The flow patterns for the cool water feeds to the production area are discussed

TRACER - TRACING AND CONTROL OF ENGINEERING REQUIREMENTS

Science.gov (United States)

Turner, P. R.

1994-01-01

TRACER (Tracing and Control of Engineering Requirements) is a database/word processing system created to document and maintain the order of both requirements and descriptive material associated with an engineering project. A set of hierarchical documents are normally generated for a project whereby the requirements of the higher level documents levy requirements on the same level or lower level documents. Traditionally, the requirements are handled almost entirely by manual paper methods. The problem with a typical paper system, however, is that requirements written and changed continuously in different areas lead to misunderstandings and noncompliance. The purpose of TRACER is to automate the capture, tracing, reviewing, and managing of requirements for an engineering project. The engineering project still requires communications, negotiations, interactions, and iterations among people and organizations, but TRACER promotes succinct and precise identification and treatment of real requirements separate from the descriptive prose in a document. TRACER permits the documentation of an engineering project's requirements and progress in a logical, controllable, traceable manner. TRACER's attributes include the presentation of current requirements and status from any linked computer terminal and the ability to differentiate headers and descriptive material from the requirements. Related requirements can be linked and traced. The program also enables portions of documents to be printed, individual approval and release of requirements, and the tracing of requirements down into the equipment specification. Requirement "links" can be made "pending" and invisible to others until the pending link is made "binding". Individuals affected by linked requirements can be notified of significant changes with acknowledgement of the changes required. An unlimited number of documents can be created for a project and an ASCII import feature permits existing documents to be incorporated

Tracer migration experiments in the Stripa mine 1980-1991

International Nuclear Information System (INIS)

Birgersson, L.; Widen, H.; Aagren, T.; Neretnieks, I.

1992-05-01

During more than 10 years, tracer experiments have been performed in the Stripa mine as part of the Stripa project to investigate the properties of both 'average' fractured rock and fracture zones. Experiments have been performed that have ranged from a few decimeters, to examine the diffusion into the rock matrix, up to tracer migration to a drift more than 50 meters from the injection point. This report compiles the results and experience that have been gained from all these tracer experiments. The experiments that are described in this report are: * The in-situ diffusion experiment where simultaneous flow and diffusion of tracers in undisturbed rock were studied over more than 3 years to validate diffusivities obtained under laboratory conditions. * Migration in a single fracture where water flow distribution and tracer transport were studied using both conservative and sorbing tracers over migration distances up to 10 meters. * The 3-D migration experiment where water inflow and tracer transport to a drift covered with 350 plastic sheet were investigated to get information on flow porosity, dispersion and channeling. The transport distances were between 10 and 56 meters from the injection points to the drift. * The channeling experiments in which the aim was to examine the channeling properties of single fractures in detail. Pressure pulse tests and tracer experiments were performed over a distances of 2 meters. * The tracer migration experiment in the validation drift where the tracer were injected mainly in a fracture zone and the collection was inside both a drift covered with plastic sheets similar to in the 3-D experiment as well as in a borehole. The distances between injection and sampling location were between 10 and 25 meters. (57 refs.) (au)

(18)F-alfatide II and (18)F-FDG dual-tracer dynamic PET for parametric, early prediction of tumor response to therapy.

Science.gov (United States)

Guo, Jinxia; Guo, Ning; Lang, Lixin; Kiesewetter, Dale O; Xie, Qingguo; Li, Quanzheng; Eden, Henry S; Niu, Gang; Chen, Xiaoyuan

2014-01-01

A single dynamic PET acquisition using multiple tracers administered closely in time could provide valuable complementary information about a tumor's status under quasiconstant conditions. This study aimed to investigate the utility of dual-tracer dynamic PET imaging with (18)F-alfatide II ((18)F-AlF-NOTA-E[PEG4-c(RGDfk)]2) and (18)F-FDG for parametric monitoring of tumor responses to therapy. We administered doxorubicin to one group of athymic nude mice with U87MG tumors and paclitaxel protein-bound particles to another group of mice with MDA-MB-435 tumors. To monitor therapeutic responses, we performed dual-tracer dynamic imaging, in sessions that lasted 90 min, starting with injection via the tail vein catheters with (18)F-alfatide II, followed 40 min later by (18)F-FDG. To achieve signal separation of the 2 tracers, we fit a 3-compartment reversible model to the time-activity curve of (18)F-alfatide II for the 40 min before (18)F-FDG injection and then extrapolated to 90 min. The (18)F-FDG tumor time-activity curve was isolated from the 90-min dual-tracer tumor time-activity curve by subtracting the fitted (18)F-alfatide II tumor time-activity curve. With separated tumor time-activity curves, the (18)F-alfatide II binding potential (Bp = k3/k4) and volume of distribution (VD) and (18)F-FDG influx rate ((K1 × k3)/(k2 + k3)) based on the Patlak method were calculated to validate the signal recovery in a comparison with 60-min single-tracer imaging and to monitor therapeutic response. The transport and binding rate parameters K1-k3 of (18)F-alfatide II, calculated from the first 40 min of the dual-tracer dynamic scan, as well as Bp and VD correlated well with the parameters from the 60-min single-tracer scan (R(2) > 0.95). Compared with the results of single-tracer PET imaging, (18)F-FDG tumor uptake and influx were recovered well from dual-tracer imaging. On doxorubicin treatment, whereas no significant changes in static tracer uptake values of (18)F-alfatide II

Blunt abdominal trauma in children.

Science.gov (United States)

Schonfeld, Deborah; Lee, Lois K

2012-06-01

This review will examine the current evidence regarding pediatric blunt abdominal trauma and the physical exam findings, laboratory values, and radiographic imaging associated with the diagnosis of intra-abdominal injuries (IAI), as well as review the current literature on pediatric hollow viscus injuries and emergency department disposition after diagnosis. The importance of the seat belt sign on physical examination and screening laboratory data remains controversial, although screening hepatic enzymes are recommended in the evaluation of nonaccidental trauma to identify occult abdominal organ injuries. Focused Assessment with Sonography for Trauma (FAST) has modest sensitivity for hemoperitoneum and IAI in the pediatric trauma patient. Patients with concern for undiagnosed IAI, including bowel injury, may be considered for hospital admission and serial abdominal exams without an increased risk of complications, if an exploratory laparotomy is not performed emergently. Although the FAST exam is not recommended as the sole screening tool to rule out IAI in hemodynamically stable trauma patients, it may be used in conjunction with the physical exam and laboratory findings to identify children at risk for IAI. Children with a normal physical exam and normal abdominal CT may not require routine hospitalization after blunt abdominal trauma.

Radioisotope tracer applications in industry

International Nuclear Information System (INIS)

Rao, S.M.

1987-01-01

Radioisotope tracers have many advantages in industrial trouble-shooting and studies on process kinetics. The applications are mainly of two types: one leading to qualitative (Yes or No type) information and the other to quantitative characterisation of flow processes through mass balance considerations and flow models. ''Yes or No'' type methods are mainly used for leakage and blockage locations in pipelines and in other industrial systems and also for location of water seepage zones in oil wells. Flow measurements in pipelines and mercury inventory in electrolytic cells are good examples of tracer methods using the mass balance approach. Axial dispersion model and Tanks-in-Series model are the two basic flow models commonly used with tracer methods for the characterisation of kinetic processes. Examples include studies on flow processes in sugar crystallisers as well as in a precalcinator in a cement plant. (author). 18 figs

Acomodación abdominal: Fisiopatología de la Distensión Abdominal

OpenAIRE

Villoria Ferrer, Albert

2011-01-01

La distensión abdominal es una alteración clínica frecuente en la población general y en especial en los pacientes afectos de trastornos funcionales digestivos donde se manifiesta de una manera más intensa. El volumen de la cavidad abdominal presenta variaciones fisiológicas en respuesta a la ingesta de alimentos, el llenado vesical o la evacuación rectal. Nuestros datos indican que cuando se realiza un incremento del volumen abdominal de forma experimental en sujetos sanos mediante la infusi...

Measurements of waste tank passive ventilation rates using tracer gases

International Nuclear Information System (INIS)

Huckaby, J.L.; Olsen, K.B.; Sklarew, D.S.; Evans, J.C.; Remund, K.M.

1997-09-01

This report presents the results of ventilation rate studies of eight passively ventilated high-level radioactive waste tanks using tracer gases. Head space ventilation rates were determined for Tanks A-101, AX-102, AX-103, BY-105, C-107, S-102, U-103, and U-105 using sulfur hexafluoride (SF 6 ) and/or helium (He) as tracer gases. Passive ventilation rates are needed for the resolution of several key safety issues. These safety issues are associated with the rates of flammable gas production and ventilation, the rates at which organic salt-nitrate salt mixtures dry out, and the estimation of organic solvent waste surface areas. This tracer gas study involves injecting a tracer gas into the tank headspace and measuring its concentration at different times to establish the rate at which the tracer is removed by ventilation. Tracer gas injection and sample collection were performed by SGN Eurisys Service Corporation and/or Lockheed Martin Hanford Corporation, Characterization Project Operations. Headspace samples were analyzed for He and SF 6 by Pacific Northwest National Laboratory (PNNL). The tracer gas method was first demonstrated on Tank S-102. Tests were conducted on Tank S-102 to verify that the tracer gas was uniformly distributed throughout the tank headspace before baseline samples were collected, and that mixing was sufficiently vigorous to maintain an approximately uniform distribution of tracer gas in the headspace during the course of the study. Headspace samples, collected from a location about 4 in away from the injection point and 15, 30, and 60 minutes after the injection of He and SF 6 , indicated that both tracer gases were rapidly mixed. The samples were found to have the same concentration of tracer gases after 1 hour as after 24 hours, suggesting that mixing of the tracer gas was essentially complete within 1 hour

Science Fair Projects. LC Science Tracer Bullet. TB 07-6

Science.gov (United States)

Howland, Joyce, Comp.

2007-01-01

Selected sources in this bibliography provide guidance to students, parents, and teachers throughout the process of planning, developing, implementing and competing in science fair activities. Sources range in suitability from elementary to high school levels. This guide updates "Library of Congress Science Tracer Bullet" 01-4. More specialized…

Abdominal tuberculosis: Imaging features

Energy Technology Data Exchange (ETDEWEB)

Pereira, Jose M. [Department of Radiology, Hospital de S. Joao, Porto (Portugal)]. E-mail: jmpjesus@yahoo.com; Madureira, Antonio J. [Department of Radiology, Hospital de S. Joao, Porto (Portugal); Vieira, Alberto [Department of Radiology, Hospital de S. Joao, Porto (Portugal); Ramos, Isabel [Department of Radiology, Hospital de S. Joao, Porto (Portugal)

2005-08-01

Radiological findings of abdominal tuberculosis can mimic those of many different diseases. A high level of suspicion is required, especially in high-risk population. In this article, we will describe barium studies, ultrasound (US) and computed tomography (CT) findings of abdominal tuberculosis (TB), with emphasis in the latest. We will illustrate CT findings that can help in the diagnosis of abdominal tuberculosis and describe imaging features that differentiate it from other inflammatory and neoplastic diseases, particularly lymphoma and Crohn's disease. As tuberculosis can affect any organ in the abdomen, emphasis is placed to ileocecal involvement, lymphadenopathy, peritonitis and solid organ disease (liver, spleen and pancreas). A positive culture or hystologic analysis of biopsy is still required in many patients for definitive diagnosis. Learning objectives:1.To review the relevant pathophysiology of abdominal tuberculosis. 2.Illustrate CT findings that can help in the diagnosis.

Demographic, dietary and physical activity predictors of general and abdominal obesity among university students: a cross-sectional study

OpenAIRE

Mogre, Victor; Nyaba, Rauf; Aleyira, Samuel; Sam, Napoleon B.

2015-01-01

Background Obesity has become a disease of global public health concern in both developing and developed countries. We investigated the influence of socio-demographic, dietary habits and physical activity levels on general and abdominal obesity among a sample of university students in Ghana. Methods This cross-sectional study was carried out among a sample of 552 students attending the University for Development Studies, School of Medicine and Health Sciences, Tamale, Ghana. Demographic chara...

Validity of a new abdominal bioelectrical impedance device to measure abdominal and visceral fat: comparison with MRI

OpenAIRE

Browning, Lucy M; Mugridge, Owen; Chatfield, Mark; Dixon, Adrian; Aitken, Sri; Joubert, Ilse; Prentice, Andrew M.; Jebb, Susan A

2010-01-01

Abdominal fat, and in particular, visceral adipose tissue (VAT), is the critical fat depot associated with metabolic aberrations. At present VAT can only be accurately measured by computed tomography (CT) or magnetic resonance imaging (MRI). This study was designed to compare a new abdominal bioelectrical impedance device against total abdominal adipose tissue (TAAT) and VAT area measurements made from an abdominal MRI scan, and to assess it’s reliability and accuracy.

Modelling and tracer studies of atmospheric dispersion and deposition in regions of complex topography

International Nuclear Information System (INIS)

Norden, C.E.

1981-11-01

An indium tracer aerosol generating apparatus based on an alcohol/oxygen burner, and an analytical procedure by which filter samples containing tracer material could be analysed quantitatively by means of neutron activation analysis, were developed for use in atmospheric dispersion and deposition studies. A number of series of atmospheric dispersion experiments were conducted in the Richards Bay and Koeberg- Cape Town areas. The results are given, comparing the airbone tracer concentrations measured at ground level with values predicted by means of a numerical model, utilising two to three schemes, varying in sophistication, for calculating the dispersion coefficients. Recommendations are given regarding a dispersion model and dispersion coefficients for regular use in the Koeberg area, and ways for estimating plume trajectories

Abdominal binders may reduce pain and improve physical function after major abdominal surgery - a systematic review

DEFF Research Database (Denmark)

Rothman, Josephine Philip; Gunnarsson, Ulf; Bisgaard, Thue

2014-01-01

INTRODUCTION: Evidence for the effect of post-operative abdominal binders on post-operative pain, seroma formation, physical function, pulmonary function and increased intra-abdominal pressure among patients after surgery remains largely un-investigated. METHODS: A systematic review was conducted...... formation and physical function. RESULTS: A total of 50 publications were identified; 42 publications were excluded leaving eight publications counting a total of 578 patients for analysis. Generally, the scientific quality of the studies was poor. Use of abdominal binder revealed a non-significant tendency...... to reduce seroma formation after laparoscopic ventral herniotomy and a non-significant reduction in pain. Physical function was improved, whereas evidence supports a beneficial effect on psychological distress after open abdominal surgery. Evidence also supports that intra-abdominal pressure increases...

Lateral abdominal muscle size at rest and during abdominal drawing-in manoeuvre in healthy adolescents.

Science.gov (United States)

Linek, Pawel; Saulicz, Edward; Wolny, Tomasz; Myśliwiec, Andrzej; Kokosz, Mirosław

2015-02-01

Lateral abdominal wall muscles in children and adolescents have not been characterised to date. In the present report, we examined the reliability of the ultrasound measurement and thickness of the oblique external muscle (OE), oblique internal muscle (OI) and transverse abdominal muscle (TrA) at rest and during abdominal drawing-in manoeuvre (ADIM) on both sides of the body in healthy adolescents. We also determined possible differences between boys and girls and defined any factors-such as body mass, height and BMI-that may affect the thickness of the abdominal muscles. B-mode ultrasound was used to assess OE, OI and TrA on both sides of the body in the supine position. Ultrasound measurements at rest and during ADIM were reliable in this age group (ICC3,3 > 0.92). OI was always the thickest and TrA the thinnest muscle on both sides of the body. In this group, an identical pattern of the contribution of the individual muscles to the structure of the lateral abdominal wall (OI > OE > TrA) was observed. At rest and during ADIM, no statistically significant side-to-side differences were demonstrated in either gender. The body mass constitutes between 30% and <50% of the thickness differences in all muscles under examination at rest and during ADIM. The structure of lateral abdominal wall in adolescents is similar to that of adults. During ADIM, the abdominal muscles in adolescents react similarly to those in adults. This study provided extensive information regarding the structure of the lateral abdominal wall in healthy adolescents. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nanoparticle tracers in calcium carbonate porous media

KAUST Repository

Li, Yan Vivian; Cathles, Lawrence M.; Archer, Lynden A.

2014-01-01

the fractures or channels where flow occurs and thus take much less time to travel between two points. In combination with a chemical tracer they can measure the degree of flow concentration. A prerequisite for tracer applications is that the particles

Tracers of cancer cells in nuclear oncology

International Nuclear Information System (INIS)

Tamgac, F.; Baillet, G.; Moretti, J.L.; Safi, N.; Weinmann, P.; Beco, V. de

1997-01-01

Evaluating the extent of disease is important in planning cancer treatment. Different types of tracers are used in vivo to diagnose tumors and these tracers can give supplementary information on the differentiation degree of tumors and response to therapy. (authors)

Changes in adhesion molecule expression and oxidative burst activity of granulocytes and monocytes during open-heart surgery with cardiopulmonary bypass compared with abdominal surgery

DEFF Research Database (Denmark)

Toft, P; Nielsen, C H; Tønnesen, Else Kirstine

1998-01-01

Cardiac and major abdominal surgery are associated with granulocytosis in peripheral blood. The purpose of the present study was to describe the granulocyte and monocyte oxidative burst and the expression of adhesion molecules following cardiac surgery with cardiopulmonary bypass and abdominal...... during cardiopulmonary bypass was observed. The percentage of CD11a-positive granulocytes increased from 30% pre-operatively to 75% following cardiopulmonary bypass, while CD44-positive granulocytes increased from 5% to 13%. Despite the extent of the changes, these were not significant. The oxidative...... to an increased per-operative oxidative burst activity, and the induction of adhesion molecules on granulocytes associated with the cardiopulmonary bypass and surgery. In conclusion, open-heart surgery with cardiopulmonary bypass was associated with a rapid and pronounced activation of leukocytes which may play...

Multiple-tracer tests for contaminant transport process identification in saturated municipal solid waste

International Nuclear Information System (INIS)

Woodman, N.D.; Rees-White, T.C.; Stringfellow, A.M.; Beaven, R.P.; Hudson, A.P.

2015-01-01

Highlights: • Multiple tracers were applied to saturated MSW to test dual-porosity properties. • Lithium demonstrated to be non-conservative as a tracer. • 260 mm diameter column too small to test transport properties of MSW. • The classical advection-dispersion mode was rejected due to high dispersivity. • Characteristic diffusion times did not vary with the tracer. - Abstract: Two column tests were performed in conditions emulating vertical flow beneath the leachate table in a biologically active landfill to determine dominant transport mechanisms occurring in landfills. An improved understanding of contaminant transport process in wastes is required for developing better predictions about potential length of the long term aftercare of landfills, currently measured in timescales of centuries. Three tracers (lithium, bromide and deuterium) were used. Lithium did not behave conservatively. Given that lithium has been used extensively for tracing in landfill wastes, the tracer itself and the findings of previous tests which assume that it has behaved conservatively may need revisiting. The smaller column test could not be fitted with continuum models, probably because the volume of waste was below a representative elemental volume. Modelling compared advection-dispersion (AD), dual porosity (DP) and hybrid AD–DP models. Of these models, the DP model was found to be the most suitable. Although there is good evidence to suggest that diffusion is an important transport mechanism, the breakthrough curves of the different tracers did not differ from each other as would be predicted based on the free-water diffusion coefficients. This suggested that solute diffusion in wastes requires further study

Multiple-tracer tests for contaminant transport process identification in saturated municipal solid waste

Energy Technology Data Exchange (ETDEWEB)

Woodman, N.D., E-mail: n.d.woodman@soton.ac.uk; Rees-White, T.C.; Stringfellow, A.M.; Beaven, R.P.; Hudson, A.P.

2015-04-15

Highlights: • Multiple tracers were applied to saturated MSW to test dual-porosity properties. • Lithium demonstrated to be non-conservative as a tracer. • 260 mm diameter column too small to test transport properties of MSW. • The classical advection-dispersion mode was rejected due to high dispersivity. • Characteristic diffusion times did not vary with the tracer. - Abstract: Two column tests were performed in conditions emulating vertical flow beneath the leachate table in a biologically active landfill to determine dominant transport mechanisms occurring in landfills. An improved understanding of contaminant transport process in wastes is required for developing better predictions about potential length of the long term aftercare of landfills, currently measured in timescales of centuries. Three tracers (lithium, bromide and deuterium) were used. Lithium did not behave conservatively. Given that lithium has been used extensively for tracing in landfill wastes, the tracer itself and the findings of previous tests which assume that it has behaved conservatively may need revisiting. The smaller column test could not be fitted with continuum models, probably because the volume of waste was below a representative elemental volume. Modelling compared advection-dispersion (AD), dual porosity (DP) and hybrid AD–DP models. Of these models, the DP model was found to be the most suitable. Although there is good evidence to suggest that diffusion is an important transport mechanism, the breakthrough curves of the different tracers did not differ from each other as would be predicted based on the free-water diffusion coefficients. This suggested that solute diffusion in wastes requires further study.

Characterization of crushed tuff for the evaluation of the fate of tracers in transport studies in the unsaturated zone

International Nuclear Information System (INIS)

Polzer, W.L.; Fuentes, H.R.; Raymond, R.; Bish, D.L.; Gladney, E.S.; Lopez, E.A.

1987-03-01

Results of field-scale (caisson) transport studies under unsaturated moisture and steady and nonsteady flow conditions indicate variability and a lack of conservation of mass in solute transport. The tuff materials used in that study were analyzed for the presence of tracers and of freshly precipitated material to help explain the variability and lack of conservation of mass. Selected tuff samples were characterized by neutron activation analysis for tracer identification, by x-ray diffraction for mineral identification, by petrographic analysis for identification of freshly precipitated material, and by x-ray fluorescence analysis for identification of major and trace elements. The results of these analyses indicate no obvious presence of freshly precipitated material that would retard tracer movement. The presence of the nonsorbing tracers (bromide and iodide) suggest the retention of these tracers in immobile water. The presence of the nonsorbing tracers (bromide and iodide) suggest the retention of these tracers in immobile water. The presence of sorbing and nonsorbing tracers on the tuff at some locations (even cesium at the 415-cm depth) and not at others suggests variability in transport. 15 refs., 14 figs., 9 tabs

Chemotherapeutic agent and tracer composition and use thereof

International Nuclear Information System (INIS)

Babb, A. L.

1985-01-01

A therapeutic composition suitable for extracorporeal treatment of whole blood comprises a dialyzable chemotherapeutic agent and a dialyzable fluorescable tracer means. The removal rate of the fluorescable tracer compound from treated blood during hemodialysis is a function of the removal rate of unreacted chemotherapeutic agent present. The residual chemotherapeutic agent concentration after hemodialysis is ascertained by measuring the concentration of the fluorescable tracer compound in a dialysate using fluorometric techniques

Intra-abdominal pressure during swimming.

Science.gov (United States)

Moriyama, S; Ogita, F; Huang, Z; Kurobe, K; Nagira, A; Tanaka, T; Takahashi, H; Hirano, Y

2014-02-01

The present study aimed to determine the intra-abdominal pressure during front crawl swimming at different velocities in competitive swimmers and to clarify the relationships between stroke indices and changes in intra-abdominal pressure. The subjects were 7 highly trained competitive collegiate male swimmers. Intra-abdominal pressure was measured during front crawl swimming at 1.0, 1.2 and 1.4 m · s(-1) and during the Valsalva maneuver. Intra-abdominal pressure was taken as the difference between minimum and maximum values, and the mean of 6 stable front crawl stroke cycles was used. Stroke rate and stroke length were also measured as stroke indices. There were significant differences in stroke rate among all velocities (P pressure and stroke rate or stroke length (P pressure and stroke indices when controlling for swimming velocity. These findings do not appear to support the effectiveness of trunk training performed by competitive swimmers aimed at increasing intra-abdominal pressure. © Georg Thieme Verlag KG Stuttgart · New York.

PET tracers for somatostatin receptor imaging of neuroendocrine tumors

DEFF Research Database (Denmark)

Johnbeck, Camilla Bardram; Knigge, Ulrich; Kjær, Andreas

2014-01-01

Neuroendocrine tumors have shown rising incidence mainly due to higher clinical awareness and better diagnostic tools over the last 30 years. Functional imaging of neuroendocrine tumors with PET tracers is an evolving field that is continuously refining the affinity of new tracers in the search...... these PET tracers further....

Use of Helium-3 and Tritium tracers in oceanography

International Nuclear Information System (INIS)

Andrie, Chantal

1987-01-01

As tritium considered as a transient tracer has become one of the most promising tool for the study of oceanic circulation and of the ocean capacity to absorb anthropogenic carbon, and as the simultaneous use of its radioactive descendant, Helium-3, brings an additional information (together, these tracers build up a clock in the study of water masses), and as all helium-3 and tritium measurements are made by mass spectroscopy, this research thesis addresses the analytical process, the detection limit, and the method reproducibility associated with this use of both tracers. The author reports and discusses helium-3 data obtained during a measurement campaign which allowed the localisation of an active source and the evidence of an intermediate back current, and tritium data obtained during another measurement campaign which allowed the description of the high time variability of convection processes, and an assessment of water renewal delays and of some deep water circulations. He also reports and discusses the simultaneous use of helium-3 data and tritium data to localize areas where convection processes occur. A theoretical approach to this simultaneous use is proposed which uses a mixing model which distinguishes the venting transit time. Measurement campaigns were performed in Red Sea, western Mediterranean Sea, and north-eastern Atlantic Ocean [fr

Combining tracer flux ratio methodology with low-flying aircraft measurements to estimate dairy farm CH4 emissions

Science.gov (United States)

Daube, C.; Conley, S.; Faloona, I. C.; Yacovitch, T. I.; Roscioli, J. R.; Morris, M.; Curry, J.; Arndt, C.; Herndon, S. C.

2017-12-01

Livestock activity, enteric fermentation of feed and anaerobic digestion of waste, contributes significantly to the methane budget of the United States (EPA, 2016). Studies question the reported magnitude of these methane sources (Miller et. al., 2013), calling for more detailed research of agricultural animals (Hristov, 2014). Tracer flux ratio is an attractive experimental method to bring to this problem because it does not rely on estimates of atmospheric dispersion. Collection of data occurred during one week at two dairy farms in central California (June, 2016). Each farm varied in size, layout, head count, and general operation. The tracer flux ratio method involves releasing ethane on-site with a known flow rate to serve as a tracer gas. Downwind mixed enhancements in ethane (from the tracer) and methane (from the dairy) were measured, and their ratio used to infer the unknown methane emission rate from the farm. An instrumented van drove transects downwind of each farm on public roads while tracer gases were released on-site, employing the tracer flux ratio methodology to assess simultaneous methane and tracer gas plumes. Flying circles around each farm, a small instrumented aircraft made measurements to perform a mass balance evaluation of methane gas. In the course of these two different methane quantification techniques, we were able to validate yet a third method: tracer flux ratio measured via aircraft. Ground-based tracer release rates were applied to the aircraft-observed methane-to-ethane ratios, yielding whole-site methane emission rates. Never before has the tracer flux ratio method been executed with aircraft measurements. Estimates from this new application closely resemble results from the standard ground-based technique to within their respective uncertainties. Incorporating this new dimension to the tracer flux ratio methodology provides additional context for local plume dynamics and validation of both ground and flight-based data.

Biological tracer for waste site characterization

International Nuclear Information System (INIS)

Strong-Gunderson, J.

1995-01-01

Remediating hazardous waste sites requires detailed site characterization. In groundwater remediation, characterizing the flow paths and velocity is a major objective. Various tracers have been used for measuring groundwater velocity and transport of contaminants, colloidal particles, and bacteria and nutrients. The conventional techniques use dissolved solutes, dyes. and gases to estimate subsurface transport pathways. These tracers can provide information on transport and diffusion into the matrix, but their estimates for groundwater flow through fractured regions are very conservative. Also, they do not have the same transport characteristics as bacteria and suspended colloid tracers, both of which must be characterized for effective in-place remediation. Bioremediation requires understanding bacterial transport and nutrient distribution throughout the acquifer, knowledge of contaminants s mobile colloidal particles is just essential

Abdominal tuberculosis. On-going challenge to gastroenterologists

International Nuclear Information System (INIS)

Ibrahim, Mahgoub; Osuba, Abimbola

2005-01-01

The aim of this study is to record the observations and experience on the diagnosis and management of abdominal tuberculosis (TB) and to highlight the difficulties in the diagnosis and management of this condition. Two hundred consecutive patients attending the Gastroenterology Department of the King Khalid National Guard Hospital, Jeddah, Kingdom of Saudi Arabia between May 1991 and May 2001, suspected with abdominal TB were investigated. A detailed clinical history and physical examination were obtained. Data of 75 confirmed cases of abdominal TB were analyzed. The most common presenting symptoms were anorexia (84%), abdominal pain (84%) and weight loss (72%). Abdominal tenderness was the most common clinical finding, followed by ascites and abdominal mass (42%). The chest radiograph suggestive of pulmonary TB was diagnosed in 24 patients (32%). Computed tomographic (CT) scanning revealed abnormalities in all 51 patients who underwent the procedure, while positive findings were observed by abdominal ultrasound in 66% of the tested patients. Histopathological examination of patients showed tuberculosis granuloma, while acid fast bacilli were seen in 34%. Mycobacterium tuberculosis was identified by microbiological methods in 60% of patients. The most common presenting symptoms were anorexia (84%), abdominal pain (84%) and weight loss (72%). Abdominal tenderness was the most common clinical finding, followed by ascites and abdominal mass (42%). The chest radiograph suggestive of pulmonary TB was diagnosed in 24 patients (32%). Computed tomographic (CT) scanning revealed abnormalities in all 51 patients who underwent the procedure, while positive findings were observed by abdominal ultrasound in 66% of the tested patients. Histopathological examination of patients showed tuberculous granuloma, while acid fast bacilli were seen in 34%. Mycobacterium tuberculosis was identified by microbiological methods in 60% of patients. A high index of clinical suspicion is

Increased pressure within the abdominal compartment: intra-abdominal hypertension and the abdominal compartment syndrome.

Science.gov (United States)

Roberts, Derek J; Ball, Chad G; Kirkpatrick, Andrew W

2016-04-01

This article reviews recent developments related to intra-abdominal hypertension (IAH)/abdominal compartment syndrome (ACS) and clinical practice guidelines published in 2013. IAH/ACS often develops because of the acute intestinal distress syndrome. Although the incidence of postinjury ACS is decreasing, IAH remains common and associated with significant morbidity and mortality among critically ill/injured patients. Many risk factors for IAH include those findings suggested to be indications for use of damage control surgery in trauma patients. Medical management strategies for IAH/ACS include sedation/analgesia, neuromuscular blocking and prokinetic agents, enteral decompression tubes, interventions that decrease fluid balance, and percutaneous catheter drainage. IAH/ACS may be prevented in patients undergoing laparotomy by leaving the abdomen open where appropriate. If ACS cannot be prevented with medical or surgical management strategies or treated with percutaneous catheter drainage, guidelines recommend urgent decompressive laparotomy. Use of negative pressure peritoneal therapy for temporary closure of the open abdomen may improve the systemic inflammatory response and patient-important outcomes. In the last 15 years, investigators have better clarified the pathogenesis, epidemiology, diagnosis, and appropriate prevention of IAH/ACS. Subsequent study should be aimed at understanding which treatments effectively lower intra-abdominal pressure and whether these treatments ultimately affect patient-important outcomes.

CT of abdominal abscesses

International Nuclear Information System (INIS)

Korobkin, M.T.

1987-01-01

The imaging search for a suspected abdominal abscess is common in hospitalized patients, especially after recent abdominal surgery. This paper examines the role of CT in the detection, localization, and treatment of abdominal abscess. The accuracy, limitations, and technical aspects of CT in this clinical setting are discussed. The diagnosis of an abscess is based on the demonstration of a circumscribed abnormal fluid collection. Although percutaneous aspiration with gram stain and culture is usually indicated to differentiate abscess from other fluid collections, the CT-based detection of extraluminal gas bubbles makes the diagnosis of an abscess highly likely. CT is compared with conventional radiographic studies, US, and radio-nuclide imaging. Specific CT and clinical features of abscesses in the following sites are emphasized: subphrenic space, liver, pancreas, kidneys, psoas muscle, appendix, and colonic diverticula. Most abdominal abscesses can be successfully treated with percutaneous drainage techniques. The techniques, results, and limitations of percutaneous abscess drainage are reviewed

Case study: evaluation of the performance of water treatment units by the use of tracer techniques

International Nuclear Information System (INIS)

Sebastian, C.; Maghella, G.; Mamani, E.

2000-12-01

Very often, water treatment systems do not reach the expected performance due to disturbances of hydraulic order, which cause malfunctioning in the flow through such systems. Tracer techniques have proved to be very useful to obtain information on the system or a part of it, by means of observation of the released tracer or observation of the released tracer during its progress into the system or at the output of the same. This paper is a report of the behavior of a set of both sand settlement unit and hydraulic flocculators in a potable water plant, through the analysis of radiotracers response curves or residence time distribution curves. The tracers released into the system consists in an aqueous solution of Iodine-131 with very low activity, in order to get a dynamic behave similar to the one of the fluid under investigation

Adult abdominal hernias.

LENUS (Irish Health Repository)

Murphy, Kevin P

2014-06-01

Educational Objectives and Key Points. 1. Given that abdominal hernias are a frequent imaging finding, radiologists not only are required to interpret the appearances of abdominal hernias but also should be comfortable with identifying associated complications and postrepair findings. 2. CT is the imaging modality of choice for the assessment of a known adult abdominal hernia in both elective and acute circumstances because of rapid acquisition, capability of multiplanar reconstruction, good spatial resolution, and anatomic depiction with excellent sensitivity for most complications. 3. Ultrasound is useful for adult groin assessment and is the imaging modality of choice for pediatric abdominal wall hernia assessment, whereas MRI is beneficial when there is reasonable concern that a patient\\'s symptoms could be attributable to a hernia or a musculoskeletal source. 4. Fluoroscopic herniography is a sensitive radiologic investigation for patients with groin pain in whom a hernia is suspected but in whom a hernia cannot be identified at physical examination. 5. The diagnosis of an internal hernia not only is a challenging clinical diagnosis but also can be difficult to diagnose with imaging: Closed-loop small-bowel obstruction and abnormally located bowel loops relative to normally located small bowel or colon should prompt assessment for an internal hernia.

The burden of abdominal obesity with physical inactivity on health expenditure in Brazil

Directory of Open Access Journals (Sweden)

Jamile S. Codogno

2015-03-01

Full Text Available The purpose of this study was to analyze the association between the clustering of physical inactivity with abdominal obesity and public health care expenditure in Brazilian adults. The sample was composed of 963 patients of both genders, randomly selected in the Brazilian Public Health care System during 2010. Entire health care expenditures during the last year were computed and stratified into: medical consultations, medication dispensing, laboratory tests and overall expenditure. Waist circumference was used to diagnose abdominal obesity and physical activity was assessed by previously validated questionnaire. Sedentary and abdominally obese patients (OR= 3.01 [OR95%CI= 1.81-4.99] had higher likelihood be inserted in the group of higher expenditures than only abdominally obese patients (OR= 1.66 [OR95%CI= 1.07-2.59]. There is a synergic effect between abdominal obesity and physical inactivity on overall health care expenditures.

Tracer methodology: an appropriate tool for assessing compliance with accreditation standards?

Science.gov (United States)

Bouchard, Chantal; Jean, Olivier

2017-10-01

Tracer methodology has been used by Accreditation Canada since 2008 to collect evidence on the quality and safety of care and services, and to assess compliance with accreditation standards. Given the importance of this methodology in the accreditation program, the objective of this study is to assess the quality of the methodology and identify its strengths and weaknesses. A mixed quantitative and qualitative approach was adopted to evaluate consistency, appropriateness, effectiveness and stakeholder synergy in applying the methodology. An online questionnaire was sent to 468 Accreditation Canada surveyors. According to surveyors' perceptions, tracer methodology is an effective tool for collecting useful, credible and reliable information to assess compliance with Qmentum program standards and priority processes. The results show good coherence between methodology components (appropriateness of the priority processes evaluated, activities to evaluate a tracer, etc.). The main weaknesses are the time constraints faced by surveyors and management's lack of cooperation during the evaluation of tracers. The inadequate amount of time allowed for the methodology to be applied properly raises questions about the quality of the information obtained. This study paves the way for a future, more in-depth exploration of the identified weaknesses to help the accreditation organization make more targeted improvements to the methodology. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Tracer dispersion in planar multipole flows

International Nuclear Information System (INIS)

Koplik, J.; Redner, S.; Hinch, E.J.

1994-01-01

We study the motion of passive Brownian tracer particles in steady two-dimensional potential flows between sources and sinks. Our primary focus is understanding the long-time properties of the transit time probability distribution for the tracer to reach the sink p(t) and the influence of the flow geometry on this probability. A variety of illustrative case studies is considered. For radial potential flow in an annular region, competition between convection and diffusion leads to nonuniversal decay of the transit time probability. Dipolar and higher multipole flows are found to exhibit generic features, such as a power-law decay in p(t) with an exponent determined by the multipole moment, an exponential cutoff related to stagnation points, and a ''shoulder'' in p(t) that is related to reflection from the system boundaries. For spatially extended sinks, it is also shown that the spatial distribution of the collected tracer is independent of the overall magnitude of the flow field and that p(t) decays as a power law with a geometry-dependent exponent. Our results may offer the possibility of using tracer measurements to characterize the flow geometry of porous media

New radioactive tracers can help find cause of jaundice

International Nuclear Information System (INIS)

Carrard, G.

1987-01-01

Radioactive tracers for the investigation of a condition known as persistent jaundice of the newborn, have been designed, prepared and tested at ANSTO. The tracers are chemical compounds of the radioactive elements gallium-67 and indium-111. They given lower radiation doses than the conventional radioactive tracer, iodine-131, used in these studies

Laplace transform in tracer kinetic modeling

Energy Technology Data Exchange (ETDEWEB)

Hauser, Eliete B., E-mail: eliete@pucrs.br [Instituto do Cerebro (InsCer/FAMAT/PUC-RS), Porto Alegre, RS, (Brazil). Faculdade de Matematica

2013-07-01

The main objective this paper is to quantify the pharmacokinetic processes: absorption, distribution and elimination of radiopharmaceutical(tracer), using Laplace transform method. When the drug is administered intravenously absorption is complete and is available in the bloodstream to be distributed throughout the whole body in all tissues and fluids, and to be eliminated. Mathematical modeling seeks to describe the processes of distribution and elimination through compartments, where distinct pools of tracer (spatial location or chemical state) are assigned to different compartments. A compartment model is described by a system of differential equations, where each equation represents the sum of all the transfer rates to and from a specific compartment. In this work a two-tissue irreversible compartment model is used for description of tracer, [{sup 18}F]2-fluor-2deoxy-D-glucose. In order to determine the parameters of the model, it is necessary to have information about the tracer delivery in the form of an input function representing the time-course of tracer concentration in arterial blood or plasma. We estimate the arterial input function in two stages and apply the Levenberg-Marquardt Method to solve nonlinear regressions. The transport of FDG across de arterial blood is very fast in the first ten minutes and then decreases slowly. We use de Heaviside function to represent this situation and this is the main contribution of this study. We apply the Laplace transform and the analytical solution for two-tissue irreversible compartment model is obtained. The only approach is to determinate de arterial input function. (author)

Effects of combined physical activity and dietary intervention on obesity and metabolic parameters in adults with abdominal obesity.

Science.gov (United States)

Soon, Heng Kiang; Saad, Hazizi Abu; Taib, Mohd Nasir Mohd; Rahman, Hejar Abd; Mun, Chan Yoke

2013-03-01

A twelve-week controlled intervention trial was carried out to evaluate the effects of combined physical activity and dietary intervention on obesity and metabolic risk factors among employees of Universiti Putra Malaysia. Participants consisted of adults aged 25-55 years with no reported chronic diseases but with abdominal obesity. They were assigned to either a combined physical activity and dietary intervention group or a control group. The final sample consisted of 56 participants, with an equal number of 28 for each study group. No significant group effect was observed for any variable except for hip circumference (HC) and fasting plasma glucose (FPG). There was a significant increase in HC (p=0.007) and reduction in FPG (p=0.02) in the intervention group compared to the control group. In the intervention group, HC (p=0.002), triglycerides (TG) (p=0.0001), total cholesterol (TC) (p=0.0001), LDL cholesterol (LDLC) (p=0.0001) and FPG (p=0.005) were significantly reduced, while waist circumference (WC) (p=0.025) and the waist-to-hip ratio (WHR) (p=0.027) were significantly reduced in the control group. No significant change in steps/day or calorie intake'was observed in either group. Taken together, these data indicate that the combined physical activity and dietary intervention was not effective at improving diet or physical activity level. However, the intervention was effective in improving FPG among participants with abdominal obesity. The significant increase in HC in the interventions group warrants further study. These findings will be useful to further improve group-based intervention for the prevention and management of obesity.

Benefits of important industrial tracer applications in the GDR

International Nuclear Information System (INIS)

Leonhardt, J.W.; Goeldner, R.; Koennecke, H.G.; Kupsch, H.; Luther, D.; Otto, R.; Reinhardt, R.; Ulrich, H.

1990-01-01

Tracers can be used to label substances or objects in order to discriminate between them, to follow their movement, to record changes of concentration and distribution between phases, etc. The main advantages of tracer investigations are the contactless recording of signals without influencing the observed process (also under rigorous operation conditions), the high detection sensitivity, the large number of available tracer nuclides (problems of all branches of industry can be solved) and the fact that tracer investigation can be carried out on operating production units, so that they provide valuable checks of the validity of design and process data. The cost-to-benefit ratio can be as low as 1:50. In the following some selected examples of tracer applications and their benefits will be presented. (orig./BBR) [de

Actinomycosis mimicking abdominal neoplasm. Case report

DEFF Research Database (Denmark)

Waaddegaard, P; Dziegiel, Morten Hanefeld

1988-01-01

In a patient with a 6-month history of nonspecific abdominal complaints, preoperative examination indicated malignant disease involving the right ovary, rectum and sigmoid, but laparotomy revealed abdominal actinomycosis. Removal of the ovary and low anterior colonic resection followed by penicil......In a patient with a 6-month history of nonspecific abdominal complaints, preoperative examination indicated malignant disease involving the right ovary, rectum and sigmoid, but laparotomy revealed abdominal actinomycosis. Removal of the ovary and low anterior colonic resection followed...... by penicillin treatment gave a good result....

Acute appendicitis after blunt abdominal trauma

Directory of Open Access Journals (Sweden)

Marjan Joudi

2012-02-01

Full Text Available Appendecitis is one of the most frequent surgeries. Inflammation of appendix may be due to variable causes such as fecalit, hypertrophy of Peyer’s plaques, seeds of fruits and parasites. In this study we presented an uncommon type of appendicitis which occurred after abdominal blunt trauma. In this article three children present who involved acute appendicitis after blunt abdominal trauma. These patients were 2 boys (5 and 6-year-old and one girl (8-year-old who after blunt abdominal trauma admitted to the hospital with abdominal pain and symptoms of acute abdomen and appendectomy had been done for them.Trauma can induce intramural hematoma at appendix process and may cause appendicitis. Therefore, physicians should be aware of appendicitis after blunt abdominal trauma

Radon as geological tracer

Energy Technology Data Exchange (ETDEWEB)

Lacerda, T.; Anjos, R.M. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Fisica; Valladares, D.L.; Rizzotto, M.; Velasco, H.; Ayub, J. Juri [Universidad Nacional de San Luis (Argentina). Inst. de Matematica Aplicada San Luis (IMASL); Silva, A.A.R. da; Yoshimura, E.M. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

2012-07-01

Full text: This work presents measurements of {sup 222}Rn levels performed in La Carolina gold mine and Los Condores tungsten mine at the province of San Luis, Argentina, today used for tourist visitation, and can evaluate the potential use of such radioactive noble gas as tracer or marker for geological processes in underground environments. By concentrations of {sup 40}K, {sup 232}Th and {sup 23}'8U were also measured in the walls of tunnels were determined the rocks mineral composition, what indicated that the mines have the same composition. In this sense, we used nuclear trace plastic detectors CR-39, gamma spectrometry of rock samples and Geiger-Muller (GM) monitors The patterns of radon gas transportation processes revealed that La Carolina could be interpreted through a model based on a radioactive gas confined into a single entrance tube, with constant cross section and air velocity. Los Condores, which has a second main entrance, could be interpreted through a model based on a radioactive gas confined into a two entrance tube, allowing a chimney effect for air circulation. The results showed the high potential of using {sup 222}Rn as a geological tracer. In what concerns the occupational hazard, in summer (time of more intense tourist activity in the mine) La Carolina presented a mean concentration of the radioactive noble gas that exceeds in four times the action level of 1,5 kBq m{sup -3} recommended by the International Commission of Radiological Protection (ICRP). The chimney effect shows the low mean concentration of radon in Los Condores. (author)

Radon as geological tracer

International Nuclear Information System (INIS)

Lacerda, T.; Anjos, R.M.; Silva, A.A.R. da; Yoshimura, E.M.

2012-01-01

Full text: This work presents measurements of 222 Rn levels performed in La Carolina gold mine and Los Condores tungsten mine at the province of San Luis, Argentina, today used for tourist visitation, and can evaluate the potential use of such radioactive noble gas as tracer or marker for geological processes in underground environments. By concentrations of 40 K, 232 Th and 23 '8U were also measured in the walls of tunnels were determined the rocks mineral composition, what indicated that the mines have the same composition. In this sense, we used nuclear trace plastic detectors CR-39, gamma spectrometry of rock samples and Geiger-Muller (GM) monitors The patterns of radon gas transportation processes revealed that La Carolina could be interpreted through a model based on a radioactive gas confined into a single entrance tube, with constant cross section and air velocity. Los Condores, which has a second main entrance, could be interpreted through a model based on a radioactive gas confined into a two entrance tube, allowing a chimney effect for air circulation. The results showed the high potential of using 222 Rn as a geological tracer. In what concerns the occupational hazard, in summer (time of more intense tourist activity in the mine) La Carolina presented a mean concentration of the radioactive noble gas that exceeds in four times the action level of 1,5 kBq m -3 recommended by the International Commission of Radiological Protection (ICRP). The chimney effect shows the low mean concentration of radon in Los Condores. (author)

Fluorinated tracers for imaging cancer with positron emission tomography

International Nuclear Information System (INIS)

Couturier, Olivier; Chatal, Jean-Francois; Luxen, Andre; Vuillez, Jean-Philippe; Rigo, Pierre; Hustinx, Roland

2004-01-01

2-[ 18 F]fluoro-2-deoxy-d-glucose (FDG) is currently the only fluorinated tracer used in routine clinical positron emission tomography (PET). Fluorine-18 is considered the ideal radioisotope for PET imaging owing to the low positron energy (0.64 MeV), which not only limits the dose rate to the patient but also results in a relatively short range of emission in tissue, thereby providing high-resolution images. Further, the 110-min physical half-life allows for high-yield radiosynthesis, transport from the production site to the imaging site and imaging protocols that may span hours, which permits dynamic studies and assessment of potentially fairly slow metabolic processes. The synthesis of fluorinated tracers as an alternative to FDG was initially tested using nucleophilic fluorination of the molecule, as performed when radiolabelling with iodine-124 or bromide-76. However, in addition to being long, with multiple steps, this procedure is not recommended for bioactive molecules containing reactive groups such as amine or thiol groups. Radiochemical yields are also often low. More recently, radiosynthesis from prosthetic group precursors, which allows easier radiolabelling of biomolecules, has led to the development of numerous fluorinated tracers. Given the wide availability of 18 F, such tracers may well develop into important routine tracers. This article is a review of the literature concerning fluorinated radiotracers recently developed and under investigation for possible PET imaging in cancer patients. Two groups can be distinguished. The first includes ''generalist'' tracers, i.e. tracers amenable to use in a wide variety of tumours and indications, very similar in this respect to FDG. These are tracers for non-specific cell metabolism, such as protein synthesis, amino acid transport, nucleic acid synthesis or membrane component synthesis. The second group consists of ''specific'' tracers for receptor expression (i.e. oestrogens or somatostatin), cell

Abdominal imaging findings in gastrointestinal basidiobolomycosis.

Science.gov (United States)

Flicek, Kristina T; Vikram, Holenarasipur R; De Petris, Giovanni D; Johnson, C Daniel

2015-02-01

To describe the abdominal imaging findings of patients with gastrointestinal Basidiobolus ranarum infection. A literature search was performed to compile the abdominal imaging findings of all reported worldwide cases of gastrointestinal basidiobolomycosis (GIB). In addition, a retrospective review at our institution was performed to identify GIB cases that had imaging findings. A radiologist aware of the diagnosis reviewed the imaging findings in detail. Additional information was obtained from the medical records. A total of 73 GIB cases have been published in the medical literature. The most common abdominal imaging findings were masses in the colon, the liver, or multiple sites and bowel wall thickening. Initially, many patients were considered to have either a neoplasm or Crohn disease. We identified 7 proven cases of GIB at our institution, of which 4 had imaging studies (4 computed tomography [CT] examinations, 4 abdominal radiographs, and an upper gastrointestinal study). Imaging studies showed abnormalities in all 4 cases. Three-fourths of our study patients had an abdominal mass at CT. Two of 3 masses involved the kidneys and included urinary obstruction. All masses showed an inflammatory component with adjacent soft tissue stranding, with or without abscess formation. Radiologists should consider GIB when a patient from an arid climate presents with abdominal pain, weight loss, and an inflammatory abdominal mass on CT. Abdominal masses of the colon or liver, bowel wall thickening, and abscesses are the most common imaging findings.

Prediction of iodine-131 biokinetics and radiation doses from therapy on the basis of tracer studies: an important question for therapy planning in nuclear medicine.

Science.gov (United States)

Willegaignon, José; Pelissoni, Rogério A; Lima, Beatriz C G D; Sapienza, Marcelo T; Coura-Filho, George B; Buchpiguel, Carlos A

2016-05-01

This study aimed to present a comparison of iodine-131 (I) biokinetics and radiation doses to red-marrow (rm) and whole-body (wb), following the administration of tracer and therapeutic activities, as a means of confirming whether I clearance and radiation doses for therapy procedures can be predicted by tracer activities. Eleven differentiated thyroid cancer patients were followed after receiving tracer and therapeutic I activity. Whole-body I clearance was estimated using radiation detectors and OLINDA/EXM software was used to calculate radiation doses to rm and wb. Tracer I activity of 86 (±14) MBq and therapeutic activity of 8.04 (±1.18) GBq were administered to patients, thereby producing an average wb I effective half-time and residence time of, respectively, 13.51 (±4.05) and 23.13 (±5.98) h for tracer activities and 13.32 (±3.38) and 19.63 (±4.77) h for therapy. Radiation doses to rm and wb were, respectively, 0.0467 (±0.0208) and 0.0589 (±0.0207) mGy/MBq in tracer studies and 0.0396 (±0.0169) and 0.0500 (±0.0163) mGy/MBq in therapy. Although the differences were not considered statistically significant between averages, those between the values of effective half-times (P=0.906), residence times (P=0.145), and radiation doses to rm (P=0.393) and to wb (P=0.272), from tracer and therapy procedures, large differences of up to 80% in wb I clearance, and up to 50% in radiation doses were observed when patients were analyzed individually, thus impacting on the total amount of I activity calculated to be safe for application in individual therapy. I biokinetics and radiation doses to rm and wb in therapy procedures are well predicted by diagnostic activities when average values of a group of patients are compared. Nonetheless, when patients are analyzed individually, significant differences may be encountered, thus implying that nuclear medicine therapy-planning requires due consideration of changes in individual patient-body status from

Abdominal imaging in AIDS patients

International Nuclear Information System (INIS)

Zhao Dawei; Wang Wei; Yuan Chunwang; Jia Cuiyu; Zhao Xuan; Zhang Tong; Ma Daqing

2007-01-01

Objective: To evaluate abdominal imaging in AIDS. Methods: The imaging examinations (including US, CT and MR) of 6 patients with AIDS associated abdominal foci were analysed retrospectively. All the cases were performed US, and CT scan, of which 4 performed enhanced CT scan and 1 with MR. Results: Abdominal tuberculosis were found in 4 patients, including abdominal lymph nodes tuberculosis (3 cases) and pancreatic tuberculosis (1 case). The imaging of lymph nodes tuberculosis typically showed enlarged peripheral tim enhancement with central low-attenuation on contrast-enhanced CT. Pancreatic tuberculosis demonstrated low-attenuation area in pancreatic head and slightly peripheral enhancement. Disseminated Kaposi's sarcoma was seen in 1 case: CT and MRI scan demonstrated tumour infiltrated along hepatic portal vein and bronchovascular bundles. Pelvic tumor was observed in 1 case: CT scan showed large mass with thick and irregular wall and central low attenuation liquefacient necrotic area in the pelvic cavity. Conclusion: The imaging findings of AIDS with abdominal foci is extraordinarily helpful to the diagnosis of such disease. Tissue biopsy is needed to confirm the diagnosis. (authors)

[Diagnostic imaging and acute abdominal pain].

Science.gov (United States)

Liljekvist, Mads Svane; Pommergaard, Hans-Christian; Burcharth, Jakob; Rosenberg, Jacob

2015-01-19

Acute abdominal pain is a common clinical condition. Clinical signs and symptoms can be difficult to interpret, and diagnostic imaging may help to identify intra-abdominal disease. Conventional X-ray, ultrasound (US) and computed tomography (CT) of the abdomen vary in usability between common surgical causes of acute abdominal pain. Overall, conventional X-ray cannot confidently diagnose or rule out disease. US and CT are equally trustworthy for most diseases. US with subsequent CT may enhance diagnostic precision. Magnetic resonance seems promising for future use in acute abdominal imaging.

Radiologic findings of abdominal wall endometriosis

Energy Technology Data Exchange (ETDEWEB)

Seo, Jung Wook [Inje Univ. Ilsan Paik Hospital, Goyang (Korea, Republic of)

2003-12-01

To evaluate the imaging findings of abdominal wall endometriosis. In seven of 17 patients with surgically proven endometriosis of the abdominal wall, we retrospectively reviewed the findings of radiologic studies such as abdominal US (n=3), CT (n=4), and MRI (n=1). One patient under went more than one type of imaging, apparently. The surgical history of the seven, and their symptoms and preoperative diagnosis were reviewed, and the size, location, margin and nature of the mass, and the contrast enhancement patterns observed at radiologic studies, were assessed. The chief symptoms were palpable abdominal wall mass (n=5) and lower abdominal pain (n=2) around a surgical scar. Previous surgery included cesarean section (n=5), cesarean section with oophorectomy (n=1) and appendectomy (n=1). Masses were located in the subcutaneous fat layer (n=5) or rectus abdominis muscle (n=2), and their maximum diameter was 2.6 cm. Imaging findings, which correlated closely with the pathologic findings, included a well (n=5) or poorly marginated (n=2) solid mass, with a focal cystic area apparent in two cases. Although imaging findings of abdominal wall endometriosis may not be specific for diagnosis, the presence of a solid abdominal mass in female patients of reproductive age with a history of surgery is a diagnostic pointer.

Radiologic findings of abdominal wall endometriosis

International Nuclear Information System (INIS)

Seo, Jung Wook

2003-01-01

To evaluate the imaging findings of abdominal wall endometriosis. In seven of 17 patients with surgically proven endometriosis of the abdominal wall, we retrospectively reviewed the findings of radiologic studies such as abdominal US (n=3), CT (n=4), and MRI (n=1). One patient under went more than one type of imaging, apparently. The surgical history of the seven, and their symptoms and preoperative diagnosis were reviewed, and the size, location, margin and nature of the mass, and the contrast enhancement patterns observed at radiologic studies, were assessed. The chief symptoms were palpable abdominal wall mass (n=5) and lower abdominal pain (n=2) around a surgical scar. Previous surgery included cesarean section (n=5), cesarean section with oophorectomy (n=1) and appendectomy (n=1). Masses were located in the subcutaneous fat layer (n=5) or rectus abdominis muscle (n=2), and their maximum diameter was 2.6 cm. Imaging findings, which correlated closely with the pathologic findings, included a well (n=5) or poorly marginated (n=2) solid mass, with a focal cystic area apparent in two cases. Although imaging findings of abdominal wall endometriosis may not be specific for diagnosis, the presence of a solid abdominal mass in female patients of reproductive age with a history of surgery is a diagnostic pointer

Screening for abdominal aortic aneurysms Rastreamento de aneurismas da aorta abdominal

Directory of Open Access Journals (Sweden)

Telmo Pedro Bonamigo

2003-01-01

Full Text Available OBJECTIVE AND METHODS: Screening for abdominal aortic aneurysms may be useful to decrease mortality related to rupture. We conducted a study to assess the prevalence of abdominal aortic aneurysms in southern Brazil and to define risk factors associated with high prevalence of this disorder. The screening was conducted using abdominal ultrasound. Three groups were studied: Group 1 - cardiology clinic patients; Group 2 - individuals with severe ischemic disease and previous coronary surgery, or important lesions on cardiac catheterism; Group 3 - individuals without cardiac disease selected from the general population. All individuals were male and older than 54 years of age. The ultrasonographic diagnosis of aneurysm was based on an anteroposterior abdominal aorta diameter of 3 cm, or on an abdominal aorta diameter 0.5 cm greater than that of the supra-renal aorta. RESULTS: A total of 2.281 people were screened for abdominal aortic aneurysms in all groups: Group 1 - 768 individuals, Group 2 - 501 individuals, and Group 3 - 1012 individuals. The prevalence of aneurysms was 4.3%, 6.8% and 1.7%, respectively. Age and cigarette smoking were significantly associated with increased prevalence of aneurysms, as was the diagnosis of peripheral artery disease. DISCUSSION: We concluded that screening may be an important tool to prevent the mortality associated with abdominal aortic aneurysms surgery. Additionally, the cost of screening can be decreased if only individuals presenting significant risk factors, such as coronary and peripheral artery disease, smokers and relatives of aneurysm patients, are examined.OBJETIVO E MÉTODOS: O rastreamento de aneurisma da aorta abdominal infra-renal é importante pois pode diminuir a mortalidade relacionada à ruptura. Realizamos um estudo para definir a prevalência desses aneurismas em diversos segmentos da população em nossa região do Brasil. O rastreamento foi realizado utilizando-se a ecografia de abdômen. Tr

COMPARISON OF THREE TRACER TESTS AT THE RAFT RIVER GEOTHERMAL SITE

Energy Technology Data Exchange (ETDEWEB)

Earl D Mattson; Mitchell Plummer; Carl Palmer; Larry Hull; Samantha Miller; Randy Nye

2011-02-01

Three conservative tracer tests have been conducted through the Bridge Fault fracture zone at the Raft River Geothermal (RRG) site. All three tests were conducted between injection well RRG-5 and production wells RRG-1 (790 m distance) and RRG-4 (740 m distance). The injection well is used during the summer months to provide pressure support to the production wells. The first test was conducted in 2008 using 136 kg of fluorescein tracer. Two additional tracers were injected in 2010. The first 2010 tracer injected was 100 kg fluorescein disodium hydrate salt on June, 21. The second tracer (100 kg 2,6-naphthalene disulfonic acid sodium salt) was injected one month later on July 21. Sampling of the two productions wells is still being performed to obtain the tail end of the second 2010 tracer test. Tracer concentrations were measured using HPLC with a fluorescence detector. Results for the 2008 test, suggest 80% tracer recover at the two production wells. Of the tracer recovered, 85% of tracer mass was recovered in well RRG-4 indicating a greater flow pathway connection between injection well and RRG-4 than RRG-1. Fluorescein tracer results appear to be similar between the 2008 and 2010 tests for well RRG-4 with peak concentrations arriving approximately 20 days after injection despite the differences between the injection rates for the two tests (~950 gpm to 475 gpm) between the 2008 and 2010. The two 2010 tracer tests will be compared to determine if the results support the hypothesis that rock contraction along the flow pathway due to the 55 oC cooler water injection alters the flow through the ~140 oC reservoir.

Focuss algorithm application in kinetic compartment modeling for PET tracer

International Nuclear Information System (INIS)

Huang Xinrui; Bao Shanglian

2004-01-01

Molecular imaging is in the process of becoming. Its application mostly depends on the molecular discovery process of imaging probes and drugs, from the mouse to the patient, from research to clinical practice. Positron emission tomography (PET) can non-invasively monitor . pharmacokinetic and functional processes of drugs in intact organisms at tracer concentrations by kinetic modeling. It has been known that for all biological systems, linear or nonlinear, if the system is injected by a tracer in a steady state, the distribution of the tracer follows the kinetics of a linear compartmental system, which has sums of exponential solutions. Based on the general compartmental description of the tracer's fate in vivo, we presented a novel kinetic modeling approach for the quantification of in vivo tracer studies with dynamic positron emission tomography (PET), which can determine a parsimonious model consisting with the measured data. This kinetic modeling technique allows for estimation of parametric images from a voxel based analysis and requires no a priori decision about the tracer's fate in vivo, instead determining the most appropriate model from the information contained within the kinetic data. Choosing a set of exponential functions, convolved with the plasma input function, as basis functions, the time activity curve of a region or a pixel can be written as a linear combination of the basis functions with corresponding coefficients. The number of non-zero coefficients returned corresponds to the model order which is related to the number of tissue compartments. The system macro parameters are simply determined using the focal underdetermined system solver (FOCUSS) algorithm. The FOCUSS algorithm is a nonparametric algorithm for finding localized energy solutions from limited data and is a recursive linear estimation procedure. FOCUSS algorithm usually converges very fast, so demands a few iterations. The effectiveness is verified by simulation and clinical

Dosimetry of ⁶⁴Cu-DOTA-AE105, a PET tracer for uPAR imaging

DEFF Research Database (Denmark)

Persson, Morten; El Ali, Henrik H.; Binderup, Tina

2014-01-01

64Cu-DOTA-AE105 is a novel positron emission tomography (PET) tracer specific to the human urokinase-type plasminogen activator receptor (uPAR). In preparation of using this tracer in humans, as a new promising method to distinguish between indolent and aggressive cancers, we have performed PET......, liver, kidney, spleen, intestine, muscle, bone and bladder. The activity concentrations in the mentioned organs [%ID/g] were used for the dosimetry calculation. The %ID/g of each organ at 1, 4.5 and 22h was scaled to human value based on a difference between organ and body weights. The scaled values...

Tracer verification and monitoring of containment systems (II)

International Nuclear Information System (INIS)

Williams, C.V.; Dunn, S.D.; Lowry, W.E.

1997-01-01

A tracer verification and monitoring system, SEAtrace trademark, has been designed and field tested which uses gas tracers to evaluate, verify, and monitor the integrity of subsurface barriers. This is accomplished using an automatic, rugged, autonomous monitoring system combined with an inverse optimization code. A gaseous tracer is injected inside the barrier and an array of wells outside the barrier are monitored. When the tracer gas is detected, a global optimization code is used to calculate the leak parameters, including leak size, location, and when the leak began. The multipoint monitoring system operates in real-time, can be used to measure both the tracer gas and soil vapor contaminants, and is capable of unattended operation for long periods of time (months). The global optimization code searches multi-dimensional open-quotes spaceclose quotes to find the best fit for all of the input parameters. These parameters include tracer gas concentration histories from multiple monitoring points, medium properties, barrier location, and the source concentration. SEAtrace trademark does not attempt to model all of the nuances associated with multi-phase, multi-component flow, but rather, the inverse code uses a simplistic forward model which can provide results which are reasonably accurate. The system has calculated leak locations to within 0.5 meters and leak radii to within 0.12 meters

Comparison of deep and superficial abdominal muscle activity between experienced Pilates and resistance exercise instructors and controls during stabilization exercise.

Science.gov (United States)

Moon, Ji-Hyun; Hong, Sang-Min; Kim, Chang-Won; Shin, Yun-A

2015-06-01

Pilates and resistance exercises are used for lumbar stabilization training. However, it is unclear which exercise is more effective for lumbar stabilization. In our study, we aimed to compare surface muscle activity and deep muscle thickness during relaxation and spinal stabilization exercise in experienced Pilates and resistance exercise instructors. This study is a retrospective case control study set in the Exercise Prescription Laboratory and Sports Medicine Center. The participants included Pilates instructors (mean years of experience, 3.20±1.76; n=10), resistance exercise instructors (mean years of experience, 2.53±0.63; n=10), and controls (n=10). The participants performed 4 different stabilization exercises: abdominal drawing-in maneuver, bridging, roll-up, and one-leg raise. During the stabilization exercises, surface muscle activity was measured with electromyography, whereas deep muscle thickness was measured by ultrasound imaging. During the 4 stabilization exercises, the thickness of the transverse abdominis (TrA) was significantly greater in the Pilates-trained group than the other 2 other groups. The internal oblique (IO) thickness was significantly greater in the Pilates- and resistance-trained group than the control group, during the 4 exercises. However, the surface muscle activities were similar between the groups. Both Pilates and resistance exercise instructors had greater activation of deep muscles, such as the TrA and IO, than the control subjects. Pilates and resistance exercise are both effective for increasing abdominal deep muscle thickness.

Safety and Efficacy of Tissue Plasminogen Activator and DNase for Complicated Pleural Effusions Secondary to Abdominal Pathology.

Science.gov (United States)

Majid, Adnan; Ochoa, Sebastian; Chatterji, Sumit; Fernandez-Bussy, Sebastian; Kheir, Fayez; Rivera, Estefania; Cheng, George; Folch, Erik

2017-03-01

Exudative pleural effusions may arise secondary to inflammation of intra-abdominal structures. Pleural space loculations can complicate these effusions, preventing adequate chest tube drainage and leading to consideration of surgical intervention. Previous studies have demonstrated that intrapleural administration of tissue plasminogen activator (tPA) combined with human recombinant DNase can improve fluid drainage and reduce surgery for patients with loculated parapneumonic effusions; however, the efficacy of this treatment has not been evaluated for complicated pleural effusions attributed to intra-abdominal inflammation. We assessed the safety and efficacy of tPA/DNase for 17 pleural effusions associated with nonmalignant intra-abdominal pathology that did not drain adequately after placement of one or more chest tubes. Efficacy was measured by comparing post- to pretreatment fluid drainage rates, volumetric assessment of pleural fluid on radiographic images before and after treatment, and clinical improvement, including the need for surgical intervention. Symptomatic relief was assessed using the Borg scale for breathlessness. After a median of two doses of tPA/DNase, 23.5% of patients had chest pain and none had pleural bleeding. The volume of pleural fluid drained increased from a median of 325 ml to 890 ml per 24 hours after therapy (P = 0.018). The area of pleural space opacity on chest radiographs decreased from a median of 42.8-17.8% of the hemithorax (P = 0.001). tPA/DNase reduced the pleural fluid volume on chest computed tomographic imaging from a median of 294.4 ml to 116.1 ml. Borg scores improved from a median of 3 (interquartile range = 1-6) to 0 (interquartile range = 0-2) after therapy (P = 0.001). The median duration of chest tube placement and hospital stay were 4 and 11 days, respectively. Two patients required surgical intervention for lung entrapment. Overall, treatment was considered successful for 88.2% of patients

A user's guide to intra-abdominal pressure measurement.

LENUS (Irish Health Repository)

Sugrue, Michael

2015-01-01

The intra-abdominal pressure (IAP) measurement is a key to diagnosing and managing critically ill medical and surgical patients. There are an increasing number of techniques that allow us to measure the IAP at the bedside. This paper reviews these techniques. IAP should be measured at end-expiration, with the patient in the supine position and ensuring that there is no abdominal muscle activity. The intravesicular IAP measurement is convenient and considered the gold standard. The level where the mid-axillary line crosses the iliac crest is the recommended zero reference for the transvesicular IAP measurement; moreover, marking this level on the patient increases reproducibility. Protocols for IAP measurement should be developed for each ICU based on the locally available tools and equipment. IAP measurement techniques are safe, reproducible and accurate and do not increase the risk of urinary tract infection. Continuous IAP measurement may offer benefits in specific situations in the future. In conclusion, the IAP measurement is a reliable and essential adjunct to the management of patients at risk of intra-abdominal hypertension.

Predictions of tracer transport in interwell tracer tests at the C-Hole complex. Yucca Mountain site characterization project report milestone 4077

International Nuclear Information System (INIS)

Reimus, P.W.

1996-09-01

This report presents predictions of tracer transport in interwell tracer tests that are to be conducted at the C-Hole complex at the Nevada Test Site on behalf of the Yucca Mountain Site Characterization Project. The predictions are used to make specific recommendations about the manner in which the tracer test should be conducted to best satisfy the needs of the Project. The objective of he tracer tests is to study flow and species transport under saturated conditions in the fractured tuffs near Yucca Mountain, Nevada, the site of a potential high-level nuclear waste repository. The potential repository will be located in the unsaturated zone within Yucca Mountain. The saturated zone beneath and around the mountain represents the final barrier to transport to the accessible environment that radionuclides will encounter if they breach the engineered barriers within the repository and the barriers to flow and transport provided by the unsaturated zone. Background information on the C-Holes is provided in Section 1.1, and the planned tracer testing program is discussed in Section 1.2

Quantifying postfire aeolian sediment transport using rare earth element tracers

Science.gov (United States)

Dukes, David; Gonzales, Howell B.; Ravi, Sujith; Grandstaff, David E.; Van Pelt, R. Scott; Li, Junran; Wang, Guan; Sankey, Joel B.

2018-01-01

Grasslands, which provide fundamental ecosystem services in many arid and semiarid regions of the world, are undergoing rapid increases in fire activity and are highly susceptible to postfire-accelerated soil erosion by wind. A quantitative assessment of physical processes that integrates fire-wind erosion feedbacks is therefore needed relative to vegetation change, soil biogeochemical cycling, air quality, and landscape evolution. We investigated the applicability of a novel tracer technique—the use of multiple rare earth elements (REE)—to quantify soil transport by wind and to identify sources and sinks of wind-blown sediments in both burned and unburned shrub-grass transition zone in the Chihuahuan Desert, NM, USA. Results indicate that the horizontal mass flux of wind-borne sediment increased approximately threefold following the fire. The REE tracer analysis of wind-borne sediments shows that the source of the horizontal mass flux in the unburned site was derived from bare microsites (88.5%), while in the burned site it was primarily sourced from shrub (42.3%) and bare (39.1%) microsites. Vegetated microsites which were predominantly sinks of aeolian sediments in the unburned areas became sediment sources following the fire. The burned areas showed a spatial homogenization of sediment tracers, highlighting a potential negative feedback on landscape heterogeneity induced by shrub encroachment into grasslands. Though fires are known to increase aeolian sediment transport, accompanying changes in the sources and sinks of wind-borne sediments may influence biogeochemical cycling and land degradation dynamics. Furthermore, our experiment demonstrated that REEs can be used as reliable tracers for field-scale aeolian studies.

Socioeconomic determinants of abdominal obesity in Medellín, Colombia

Directory of Open Access Journals (Sweden)

Luz S Álvarez-Castaño

2014-12-01

Full Text Available Introduction: Excess weight associated with the distribution of body fat is one of the major risk factors for morbidity and mortality. This study analyzes data obtained from the survey “Food and Nutritional Profile of Medellín” carried out in 2010, aimed to establish some socio economic determinants of abdominal obesity.Material and Methods: Study descriptive, cross-sectional, the sample consisted of 2719 households and 5556 adults, ages 18 to 64. Abdominal obesity was assessed as >80cm for females and >94 cm for males. The social and economic determinants analyzed were family monthly income measured as the capacity to cover a basic food basket (>USD777, educational level, social stratum measured by the house and neighborhood characteristics and occupational activity as measured by the National Department of Statistics of Colombia.Results: The prevalence of abdominal obesity was 45%, higher in women than in men (55% vs 27%. Related to social determinants, abdominal obesity is higher in persons of low (OR 1,8; CI95% 1.4-2.2 and medium stratum (OR 1.6; CI95% 1.3-2.0. It affects persons with primary/elementary educational levels (OR 1.9; CI95% 1.7-2.3 more than those of high school education (OR 1.5; CI95% 1.3-1.7. Likewise abdominal obesity is higher among those with a family income less than (USD777 –not enough to acquire the basic food basket– (OR 1.6; CI95% 1.3-1.9. In men family income shows no association with abdominal obesity.Conclusions: For this population some social determinants of abdominal obesity are level of education, social stratum and family income.

Suitability of tracers; Eignung von Tracern

Energy Technology Data Exchange (ETDEWEB)

Klotz, D. [GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg (Germany). Inst. fuer Hydrologie

1999-02-01

Hydrological tracer techniques are a means of making statements on the direction and speed of underground water. One of the simpler tasks is to find out whether there is hydrological communication between two given points. This requires a determination of the direction of flow, which places less exacting demands on the properties of the tracer than does the task of determining the flow velocity of underground water. Tracer methods can serve to infer from flow velocity the distance (flow) velocity, which is defined as the ratio between the distance between two points located in flow direction and the actual time it takes water to flow from one to the other. [Deutsch] Mit Hilfe der hydrologischen Markierungstechniken koennen Aussagen ueber die Richtung und die Geschwindigkeit von Bewegungen des unterirdischen Wassers gemacht werden. Der einfachere Fall liegt vor, wenn festgestellt werden soll, ob zwischen zwei Punkten eine hydrologische Verbindung besteht. Bei dieser Fliessrichtungsbestimmung sind die Forderungen an die Eigenschaften der einzusetzenden Tracer geringer als bei der Bestimmung der Geschwindigkeit des unterirdischen Wassers. Von den Geschwindigkeiten des unterirdischen Wassers ist die Abstands-(Fliess)geschwindigkeit, die definiert ist durch das Verhaeltnis aus dem Abstand und der wahren Fliesszeit zwischen zwei in Bewegungsrichtung gelegenen Punkten, durch Tracermethoden zu bestimmen. (orig.)

Pipeline leak detection using volatile tracers

International Nuclear Information System (INIS)

Thompson, G.M.; Golding, R.D.

1993-01-01

A method of leak detection for underground storage tanks and pipelines adds volatile tracers to the products in the tanks and analyzes the surrounding shallow soil gases for tracer vapors. This method has several advantages: the success of the test is not limited by the size and structural design of the vessels, tanks can be tested at any fill level without taking the tank out of service, the location of a leak along a pipeline is clearly marked by the location of the tracer, and liquid leaks as small as 0.2 liters per hour (lph) can be detected. A limitation is: the backfill material must have some degree of air permeability in the zone above the water table. Several field tests document the success achieved using this method. A tracer leak detection system was installed at Homestead AFB after several other testing methods failed to locate a leak at a valve pit location along approximately 4 kilometers of fuel transfer piping. The leak was detected to the side of the valve pit at a depth of approximately 2.5 meters below the ground surface. Another installation of Edwards AFB involved the collection of 415 soil gas samples along approximately 3,050 meters of 15.25-centimeter fiberglass pipeline. Fourteen separate leaks were detected

Physical activity reduces the risk of incident type 2 diabetes in general and in abdominally lean and obese men and women: the EPIC-InterAct Study.

Science.gov (United States)

Ekelund, U; Palla, L; Brage, S; Franks, P W; Peters, T; Balkau, B; Diaz, M J T; Huerta, J M; Agnoli, C; Arriola, L; Ardanaz, E; Boeing, H; Clavel-Chapelon, F; Crowe, F; Fagherazzi, G; Groop, L; Føns Johnsen, N; Kaaks, R; Khaw, K T; Key, T J; de Lauzon-Guillain, B; May, A; Monninkhof, E; Navarro, C; Nilsson, P; Nautrup Østergaard, J; Norat, T; Overvad, K; Palli, D; Panico, S; Redondo, M L; Ricceri, F; Rolandsson, O; Romaguera, D; Romieu, I; Sánchez Pérez, M J; Slimani, N; Spijkerman, A; Teucher, B; Tjonneland, A; Travier, N; Tumino, R; Vos, W; Vigl, M; Sharp, S; Langeberg, C; Forouhi, N; Riboli, E; Feskens, E; Wareham, N J

2012-07-01

We examined the independent and combined associations of physical activity and obesity with incident type 2 diabetes in men and women. The InterAct case-cohort study consists of 12,403 incident type 2 diabetes cases and a randomly selected subcohort of 16,154 individuals, drawn from a total cohort of 340,234 participants with 3.99 million person-years of follow-up. Physical activity was assessed by a four-category index. Obesity was measured by BMI and waist circumference (WC). Associations between physical activity, obesity and case-ascertained incident type 2 diabetes were analysed by Cox regression after adjusting for educational level, smoking status, alcohol consumption and energy intake. In combined analyses, individuals were stratified according to physical activity level, BMI and WC. A one-category difference in physical activity (equivalent to approximately 460 and 365 kJ/day in men and women, respectively) was independently associated with a 13% (HR 0.87, 95% CI 0.80, 0.94) and 7% (HR 0.93, 95% CI 0.89, 0.98) relative reduction in the risk of type 2 diabetes in men and women, respectively. Lower levels of physical activity were associated with an increased risk of diabetes across all strata of BMI. Comparing inactive with active individuals, the HRs were 1.44 (95% CI 1.11, 1.87) and 1.38 (95% CI 1.17, 1.62) in abdominally lean and obese inactive men, respectively, and 1.57 (95% CI 1.19, 2.07) and 1.19 (95% CI 1.01, 1.39) in abdominally lean and obese inactive women, respectively. Physical activity is associated with a reduction in the risk of developing type 2 diabetes across BMI categories in men and women, as well as in abdominally lean and obese men and women.

Abdominal compartment syndrome with acute reperfusion syndrome

International Nuclear Information System (INIS)

Maleeva, A.

2017-01-01

Abdominal compartment syndrome was recognized clinically in the 19th century when Marey and Burt observed its association with declines in respiratory function. Abdominal compartment syndrome is first used as a medical terminology from Fietsman in a case of ruptured abdominal aortic aneurysm. A condition caused by abnormally increased pressure within the abdomen. Causes of abdominal compartment syndrome include trauma, surgery, or infection. Common symptoms: abdominal distension, fast heart rate, insufficient urine production, or low blood pressure Medical procedure: nasogastric intubation Surgery: laparotomy Specialists: radiologist, primary care provider (PCP), surgeon, and emergency medicine doctor [6, 10]. Keywords: Stomach. Gastroparesis . Diabetes Mellitus [bg

Association of ficolin-3 with abdominal aortic aneurysm presence and progression

DEFF Research Database (Denmark)

Fernandez-García, C-E; Burillo, E; Lindholt, J S

2017-01-01

Essentials Abdominal aortic aneurysm (AAA) is asymptomatic and its evolution unpredictable. To find novel potential biomarkers of AAA, microvesicles are an excellent source of biomarkers. Ficolin-3 is increased in microvesicles obtained from activated platelets and AAA tissue. Increased ficolin-3...... plasma levels are associated with AAA presence and progression. SUMMARY: Background Abdominal aortic aneurysm (AAA) patients are usually asymptomatic and AAA evolution is unpredictable. Ficolin-3, mainly synthesized by the liver, is a molecule of the lectin complement-activation pathway involved in AAA...... pathophysiology. Objectives To define extra-hepatic sources of ficolin-3 in AAA and investigate the role of ficolin-3 as a biomarker of the presence and progression of AAA. Methods Microvesicles (exosomes and microparticles) were isolated from culture-conditioned medium of ADP-activated platelets, as well as from...

Evaluation of single- and dual-porosity models for reproducing the release of external and internal tracers from heterogeneous waste-rock piles.

Science.gov (United States)

Blackmore, S; Pedretti, D; Mayer, K U; Smith, L; Beckie, R D

2018-05-30

Accurate predictions of solute release from waste-rock piles (WRPs) are paramount for decision making in mining-related environmental processes. Tracers provide information that can be used to estimate effective transport parameters and understand mechanisms controlling the hydraulic and geochemical behavior of WRPs. It is shown that internal tracers (i.e. initially present) together with external (i.e. applied) tracers provide complementary and quantitative information to identify transport mechanisms. The analysis focuses on two experimental WRPs, Piles 4 and Pile 5 at the Antamina Mine site (Peru), where both an internal chloride tracer and externally applied bromide tracer were monitored in discharge over three years. The results suggest that external tracers provide insight into transport associated with relatively fast flow regions that are activated during higher-rate recharge events. In contrast, internal tracers provide insight into mechanisms controlling solutes release from lower-permeability zones within the piles. Rate-limited diffusive processes, which can be mimicked by nonlocal mass-transfer models, affect both internal and external tracers. The sensitivity of the mass-transfer parameters to heterogeneity is higher for external tracers than for internal tracers, as indicated by the different mean residence times characterizing the flow paths associated with each tracer. The joint use of internal and external tracers provides a more comprehensive understanding of the transport mechanisms in WRPs. In particular, the tracer tests support the notion that a multi-porosity conceptualization of WRPs is more adequate for capturing key mechanisms than a dual-porosity conceptualization. Copyright © 2018 Elsevier B.V. All rights reserved.

Determination of the self purification of streams using tracers

International Nuclear Information System (INIS)

Salviano, J.S.

1982-04-01

A methodology for the 'in situ' evaluation of the self purification of streams is discussed. It consists of the simultaneous injection of two tracers into the stream. One of the tracers is oxidized by biochemical processes. It can be either artificially supplied to the stream or a naturally present component can be used. This tracer is used for the determination of the self purification parameters. The other tracer is conservative and allows for the hydrodynamic effects. Tests have been carried out in two streams with quite different hydrodynamic and physicochemical conditions. In the first stream, with a flow-rate of about 0.9 m 3 /s, urea was used as the nonconservative tracer. In the other stream, which had a flow-rate of about 5 m 3 /s, only a radioactive tracer has been used, and the rate of biochemical oxidation has been determined from BOD measurements. Calculations have been implemented on a digital computer. In both cases it was found that the reoxygenation rate is more conveniently determined by empirical formulas. Results from both tests have been deemed realistic by comparison with similar experiments. (Author) [pt

Towards tracer dose reduction in PET studies: Simulation of dose reduction by retrospective randomized undersampling of list-mode data.

Science.gov (United States)

Gatidis, Sergios; Würslin, Christian; Seith, Ferdinand; Schäfer, Jürgen F; la Fougère, Christian; Nikolaou, Konstantin; Schwenzer, Nina F; Schmidt, Holger

2016-01-01

Optimization of tracer dose regimes in positron emission tomography (PET) imaging is a trade-off between diagnostic image quality and radiation exposure. The challenge lies in defining minimal tracer doses that still result in sufficient diagnostic image quality. In order to find such minimal doses, it would be useful to simulate tracer dose reduction as this would enable to study the effects of tracer dose reduction on image quality in single patients without repeated injections of different amounts of tracer. The aim of our study was to introduce and validate a method for simulation of low-dose PET images enabling direct comparison of different tracer doses in single patients and under constant influencing factors. (18)F-fluoride PET data were acquired on a combined PET/magnetic resonance imaging (MRI) scanner. PET data were stored together with the temporal information of the occurrence of single events (list-mode format). A predefined proportion of PET events were then randomly deleted resulting in undersampled PET data. These data sets were subsequently reconstructed resulting in simulated low-dose PET images (retrospective undersampling of list-mode data). This approach was validated in phantom experiments by visual inspection and by comparison of PET quality metrics contrast recovery coefficient (CRC), background-variability (BV) and signal-to-noise ratio (SNR) of measured and simulated PET images for different activity concentrations. In addition, reduced-dose PET images of a clinical (18)F-FDG PET dataset were simulated using the proposed approach. (18)F-PET image quality degraded with decreasing activity concentrations with comparable visual image characteristics in measured and in corresponding simulated PET images. This result was confirmed by quantification of image quality metrics. CRC, SNR and BV showed concordant behavior with decreasing activity concentrations for measured and for corresponding simulated PET images. Simulation of dose

Mechanical characterization of porcine abdominal organs.

Science.gov (United States)

Tamura, Atsutaka; Omori, Kiyoshi; Miki, Kazuo; Lee, Jong B; Yang, King H; King, Albert I

2002-11-01

Typical automotive related abdominal injuries occur due to contact with the rim of the steering wheel, seatbelt and armrest, however, the rate is less than in other body regions. When solid abdominal organs, such as the liver, kidneys and spleen are involved, the injury severity tends to be higher. Although sled and pendulum impact tests have been conducted using cadavers and animals, the mechanical properties and the tissue level injury tolerance of abdominal solid organs are not well characterized. These data are needed in the development of computer models, the improvement of current anthropometric test devices and the enhancement of our understanding of abdominal injury mechanisms. In this study, a series of experimental tests on solid abdominal organs was conducted using porcine liver, kidney and spleen specimens. Additionally, the injury tolerance of the solid organs was deduced from the experimental data.

Experimental study of abdominal CT scanning exposal doses adjusted on the basis of pediatric abdominal perimeter

International Nuclear Information System (INIS)

Wei Wenzhou; Zhu Gongsheng; Zeng Lingyan; Yin Xianglin; Yang Fuwen; Liu Changsheng

2006-01-01

Objective: To optimize the abdominal helical CT scanning parameters in pediatric patients and to reduce its radiation hazards. Methods: 60 canines were evenly grouped into 4 groups on the basis of pediatric abdominal perimeter, scanned with 110,150,190 and 240 mAs, and their qualities of canine CT images were analyzed. 120 pediafric patients with clinic suspected abdominal diseases were divided into 4 groups on the basis of abdominal perimeter, scanned by optimal parameters and their image qualities were analyzed. Results: After CT exposure were reduced, the percentages of total A and B were 90.9 % and 92.0 % in experimental canines and in pediatric patients, respectively. Compared with conventional CT scanning, the exposure and single slice CT dose index weighted (CTDIw) were reduced to 45.8%-79.17%. Conclusion: By adjusted the pediatric helical CT parameters basedon the of pediatric abdominal perimeter, exposure of patient to the hazards of radiation is reduced. (authors)

Wirelessly powered micro-tracer enabled by miniaturized antenna and microfluidic channel

International Nuclear Information System (INIS)

Duan, G; Zhao, X; Seren, H R; Chen, C; Zhang, X

2015-01-01

A miniaturized antenna, 380μm by 380μm in size, was fabricated and integrated with a commercialized passive RFID chip to form a micro-tracer, whose size was 2mm by 1mm in total. The micro-tracer was wirelessly powered and interrogated by a single layer spiral reader antenna through near field coupling. To maximize the working distance, the resonant frequency of micro-tracer and reader antenna were matched at 840MHz. Due to the ultra small size of the tracer antenna, power transfer efficiency decreased dramatically as the distance between tracer antenna and reader antenna increased, thus the working distance of the microtracer was limited within 1mm. To achieve massive operation of the micro-tracer, a microfluidic platform was fabricated with in channel focusing and separation. Acrylic sheets were laser cut to define the channel and cover structure, then bonded together layer by layer with a glass substrate, on which reader antenna was integrated. Pump oil was used as the fluidic media carrying the micro-tracer flowing inside the microfluidic channel. The wireless power transfer and real-time communication was demonstrated with the micro-tracer flowing above the reader antenna, as the ID of the micro-tracer was retrieved and displayed on a computer screen. (paper)

Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... particularly valuable for evaluating abdominal, pelvic or scrotal pain in children. Preparation will depend on the type ... help a physician determine the source of abdominal pain, such as gallstones, kidney stones, abscesses or an ...

Abdominal epilepsy in a Nigerian child S

African Journals Online (AJOL)

Abdominal epilepsy is an exceptionally rare cause of abdominal pain that is more likely to ... We report on a child with episodic paroxysmal abdominal pain, accompanied by ... causes for the presenting complaints, work-up should proceed.

Quantitative Visualization of Dynamic Tracer Transportation in the Extracellular Space of Deep Brain Regions Using Tracer-Based Magnetic Resonance Imaging

Science.gov (United States)

Hou, Jin; Wang, Wei; Quan, Xianyue; Liang, Wen; Li, Zhiming; Han, Hongbin; Chen, Deji

2017-01-01

Background This study assessed an innovative tracer-based magnetic resonance imaging (MRI) system to visualize the dynamic transportation of tracers in regions of deep brain extracellular space (ECS) and to measure transportation ability and ECS structure. Material/Methods Gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) was the chosen tracer and was injected into the caudate nucleus and thalamus. Real-time dynamic transportation of Gd-DTPA in ECS was observed and the results were verified by laser scanning confocal microscopy. Using Transwell assay across the blood-brain barrier, a modified diffusion equation was further simplified. Effective diffusion coefficient D* and tortuosity λ were calculated. Immunohistochemical staining and Western blot analysis were used to investigate the extracellular matrix contributing to ECS structure. Results Tracers injected into the caudate nucleus were transported to the ipsilateral frontal and temporal cortices away from the injection points, while both of them injected into the thalamus were only distributed on site. Although the caudate nucleus was closely adjacent to the thalamus, tracer transportation between partitions was not observed. In addition, D* and the λ showed statistically significant differences between partitions. ECS was shown to be a physiologically partitioned system, and its division is characterized by the unique distribution territory and transportation ability of substances located in it. Versican and Tenascin R are possible contributors to the tortuosity of ECS. Conclusions Tracer-based MRI will improve our understanding of the brain microenvironment, improve the techniques for local delivery of drugs, and highlight brain tissue engineering fields in the future. PMID:28866708

Quantitative Visualization of Dynamic Tracer Transportation in the Extracellular Space of Deep Brain Regions Using Tracer-Based Magnetic Resonance Imaging.

Science.gov (United States)

Hou, Jin; Wang, Wei; Quan, Xianyue; Liang, Wen; Li, Zhiming; Chen, Deji; Han, Hongbin

2017-09-03

BACKGROUND This study assessed an innovative tracer-based magnetic resonance imaging (MRI) system to visualize the dynamic transportation of tracers in regions of deep brain extracellular space (ECS) and to measure transportation ability and ECS structure. MATERIAL AND METHODS Gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) was the chosen tracer and was injected into the caudate nucleus and thalamus. Real-time dynamic transportation of Gd-DTPA in ECS was observed and the results were verified by laser scanning confocal microscopy. Using Transwell assay across the blood-brain barrier, a modified diffusion equation was further simplified. Effective diffusion coefficient D* and tortuosity λ were calculated. Immunohistochemical staining and Western blot analysis were used to investigate the extracellular matrix contributing to ECS structure. RESULTS Tracers injected into the caudate nucleus were transported to the ipsilateral frontal and temporal cortices away from the injection points, while both of them injected into the thalamus were only distributed on site. Although the caudate nucleus was closely adjacent to the thalamus, tracer transportation between partitions was not observed. In addition, D* and the λ showed statistically significant differences between partitions. ECS was shown to be a physiologically partitioned system, and its division is characterized by the unique distribution territory and transportation ability of substances located in it. Versican and Tenascin R are possible contributors to the tortuosity of ECS. CONCLUSIONS Tracer-based MRI will improve our understanding of the brain microenvironment, improve the techniques for local delivery of drugs, and highlight brain tissue engineering fields in the future.

Using neural networks to describe tracer correlations

Directory of Open Access Journals (Sweden)

D. J. Lary

2004-01-01

Full Text Available Neural networks are ideally suited to describe the spatial and temporal dependence of tracer-tracer correlations. The neural network performs well even in regions where the correlations are less compact and normally a family of correlation curves would be required. For example, the CH4-N2O correlation can be well described using a neural network trained with the latitude, pressure, time of year, and methane volume mixing ratio (v.m.r.. In this study a neural network using Quickprop learning and one hidden layer with eight nodes was able to reproduce the CH4-N2O correlation with a correlation coefficient between simulated and training values of 0.9995. Such an accurate representation of tracer-tracer correlations allows more use to be made of long-term datasets to constrain chemical models. Such as the dataset from the Halogen Occultation Experiment (HALOE which has continuously observed CH4  (but not N2O from 1991 till the present. The neural network Fortran code used is available for download.

Using radioactive tracer technique in municipal hygiene

International Nuclear Information System (INIS)

Yurasova, O.I.

1974-01-01

Work of the A. N. Syrsin Institute of General and Municiapl Hygiene using raidoactive tracers is reviewed. The studies include research on protein metabolism in the living organism following action of unfavorable factors of the environment; determination of the paths of introduction into the organism of substances with an alien composition; and study of the rate of resorption of subcutaneous papuli. Results are shown of radioactive-tracer studies on the mechanism of action of poisonous substances on the living organism and of migration of alien chemical compounds in the organism and in objects in the environment. It is concluded that the radioactive tracer method has wide application in municipal hygiene and sanitary microbiology. The absence of laborious operations, economy of time, precision of the experiments, and the possibility of obtaining additional information on the mechanism of action of poisonous substances on the organism and the low cost of such studies compared with other methods makes the radioactive tracer method economically attractive. The studies made show the various types of use of the method in municipal hygiene and sanitary microbiology

Using radioactive tracer technique in municipal hygiene

Energy Technology Data Exchange (ETDEWEB)

Yurasova, O I [Institut Obshchej i Kommunal' noj Gigieny, Moscow (USSR)

1974-01-01

Work of the A. N. Syrsin Institute of General and Municiapl Hygiene using raidoactive tracers is reviewed. The studies include research on protein metabolism in the living organism following action of unfavorable factors of the environment; determination of the paths of introduction into the organism of substances with an alien composition; and study of the rate of resorption of subcutaneous papuli. Results are shown of radioactive-tracer studies on the mechanism of action of poisonous substances on the living organism and of migration of alien chemical compounds in the organism and in objects in the environment. It is concluded that the radioactive tracer method has wide application in municipal hygiene and sanitary microbiology. The absence of laborious operations, economy of time, precision of the experiments, and the possibility of obtaining additional information on the mechanism of action of poisonous substances on the organism and the low cost of such studies compared with other methods makes the radioactive tracer method economically attractive. The studies made show the various types of use of the method in municipal hygiene and sanitary microbiology.

DIEP breast reconstruction following multiple abdominal liposuction procedures

OpenAIRE

Farid, Mohammed; Nicholson, Simon; Kotwal, Ashutosh; Akali, Augustine

2014-01-01

Objective: Previous abdominal wall surgery is viewed as a contraindication to abdominal free tissue transfer. We present two patients who underwent multiple abdominal liposuction procedures, followed by successful free deep inferior epigastric artery perforator flap. We review the literature pertaining to reliability of abdominal free flaps in those with previous abdominal surgery. Methods: Review of case notes and radiological investigations of two patients, and a PubMed search using the ter...

Recovery after abdominal wall reconstruction

DEFF Research Database (Denmark)

Jensen, Kristian Kiim

2017-01-01

Incisional hernia is a common long-term complication to abdominal surgery, occurring in more than 20% of all patients. Some of these hernias become giant and affect patients in several ways. This patient group often experiences pain, decreased perceived body image, and loss of physical function......, which results in a need for surgical repair of the giant hernia, known as abdominal wall reconstruction. In the current thesis, patients with a giant hernia were examined to achieve a better understanding of their physical and psychological function before and after abdominal wall reconstruction. Study...... was lacking. Study II was a case-control study of the effects of an enhanced recovery after surgery pathway for patients undergoing abdominal wall reconstruction for a giant hernia. Sixteen consecutive patients were included prospectively after the implementation of a new enhanced recovery after surgery...

Abdominal angina

International Nuclear Information System (INIS)

Becker, G.J.; Stewart, J.; Holden, R.W.; Yune, H.Y.; Mail, J.T.; Klatte, E.C.

1988-01-01

Abdominal angina due to occlusive disease of the mesenteric arteries has been the to become clinically manifest only in the presence of severe disease in at least two of the following vessels: celiac, SMA, and IMA. Still, many patients who gradually develop significant two-vessel disease have few or no associated symptoms. Differences in collateral circulation and in cardiac index account for some of the clinical variation. The usual clinical manifestations include severe post-prandial pain, sitophobia (fear of eating because of the anticipated symptoms), and profound weight loss. Uncommonly, diarrhea, nausea, or vomiting may be encountered. Smoking is a common historical feature. Most series document a female predilection. Aside from occasional abdominal bruits and (more commonly) findings of peripheral vascular occlusive disease, the physical exam discloses only cachexia. But the differential diagnosis of profound weight loss is extensive. Therefore, abdominal angina has always created a diagnostic challenge. Multiple imaging modalities are often employed, and a seemingly negative evaluation often culminates in biplane aortography. The latter typically reveals stenoses and/or occlusions in at least two of the three mesenteric arteries. The authors discuss how a variety of surgical treatments, including thromboendarterectomy and bypass grafting, have evolved. Recently reported results have been excellent

Methods of 15N tracer research in biological systems

International Nuclear Information System (INIS)

Hirschberg, K.; Faust, H.

1985-01-01

The application of the stable isotope 15 N is of increasing importance in different scientific disciplines, especially in medicine, agriculture, and the biosciences. The close correlation between the growing interest and improvements of analytical procedures resulted in remarkable advances in the 15 N tracer technique. On the basis of the latest results of 15 N tracer research in life sciences and agriculture methods of 15 N tracer research in biological systems are compiled. The 15 N methodology is considered under three headings: Chemical analysis with a description of methods of sample preparation (including different separation and isolation methods for N-containing substances of biological and agricultural origin) and special procedures converting ammonia to molecular nitrogen. Isotopic analysis with a review on the most important methods of isotopic analysis of nitrogen: mass spectrometry (including the GC-MS technique), emission spectrometry, NMR spectroscopy, and other analytical procedures. 15 N-tracer techniques with a consideration of the role of the isotope dilution analysis as well as different labelling techniques and the mathematical interpretation of tracer data (modelling, N turnover experiments). In these chapters also sources of errors in chemical and isotopic analysis, the accuracy of the different methods and its importance on tracer experiments are discussed. Procedures for micro scale 15 N analysis and aspects of 15 N analysis on the level of natural abundance are considered. Furthermore some remarks on isotope effects in 15 N tracer experiments are made. (author)

Radiographic evaluation of foals and ponies with abdominal disorders. 2. Findings in 60 patients with acute abdominal discomfort

International Nuclear Information System (INIS)

Gerhards, H.; Klein, H.J.; Offeney, F.

1990-01-01

A diagnostic approach based on clinical and radiographic examinations for evaluation of young foals and small ponies with acute abdominal discomfort is presented. Standing right to left lateral abdominal radiographs were taken of 54 foals and 6 ponies using a previously described technique. Interpretation of the radiographs was in conjuction with all clinical and laboratory findings and patient management. Using this approach, the site and cause of acute abdominal discomfort could be diagnosed accurately in 55 of 60 (91%) patients as confirmed by clinical, surgical or PM findings. Typical radiographs and photographs taken at surgery or at PM examination are presented. Typical radiographic findings, their interpretation and possible underlying gastrointestinal diseases are listed. It is concluded that the incorporation of standing lateral abdominal radiography in the clinical evaluation of foals and ponies with acute abdominal diseases gives findings of high diagnostic significance and should contribute to clinical decision-making, and that abdominal radiography can replace data from rectal palpation in foals and ponies

Preliminary evidence for increased parasympathetic activity during social inclusion and exclusion in adolescents with functional abdominal pain.

Science.gov (United States)

Gulewitsch, Marco Daniel; Jusyte, Aiste; Mazurak, Nazar; Weimer, Katja; Schönenberg, Michael

2017-07-01

Peer victimization (e.g. social exclusion) has been shown to be associated with physical health problems such as functional somatic complaints and especially symptoms of pain. To date, no study has investigated the mechanisms underlying this association in clinical pediatric samples. The aim of this study was to evaluate the parasympathetic activity during a social exclusion experience in adolescents with functional abdominal pain (FAP). Twenty adolecents with FAP and 21 matched healthy participants were compared regarding parameters of parasympathetic activation before, during, and after participating in the Cyberball-game, a well-established paradigm to induce social exclusion. Adolescents with FAP showed an increase in parasympathetic activation during both consecutive phases of the Cyberball game (inclusion as well as exclusion condition) whereas the healthy control group remained stable. There were no differences in subjective experience of in- and exclusion between the groups. The parasympathetic activation pattern may indicate altered processing of social stimuli in adolescents with FAP. Copyright © 2017 Elsevier Inc. All rights reserved.

Tracer experiment by using radioisotope in surface water environment

International Nuclear Information System (INIS)

Suh, K.S.; Kim, K.C.; Chun, I.Y.; Jung, S.H.; Lee, C.W.

2007-01-01

Complete text of publication follows. 1. Objective An expansion of industrial activities and urbanization result in still increasing amount of pollutants discharged into surface water. Discharged pollutants in surface water have harmful effects on the ecology of a river system and human beings. Pollutants discharged into surface water is transported and dispersed under conditions characteristic to particular natural water receiver. Radiotracer method is a useful tool for monitoring the pollutant dispersion and description of mixing process taking place in natural streams. A tracer experiment using radioisotope was carried out to investigate the characteristics of a pollutant transport and a determination of the diffusion coefficients in a river system. 2. Methods The upper area of the Keum river was selected for the tracer experiment, which is located in a mid west of Korea. The measurements of the velocity and bathymetry before a tracer experiment were performed to select the sampling lines for a detection of the radioisotope. The radioisotope was instantaneously injected into a flow as a point source by an underwater glass-vial crusher. The detection was made with 60 2inch NaI(Tl) scintillation detectors at 3 transverse lines at a downstream position. The multi-channel data acquisition systems were used to collect and process the signals transmitted from the detectors. Two-dimensional numerical models were used to simulate the hydraulic parameters and the concentration distributions of the radioisotope injected into the river. 3. Results and Conclusion The calculated results such as velocity and concentrations were compared with the measured ones. The dispersion characteristics of the radioisotope were analyzed according to a variation of the flow rate, water level and diffusion coefficients. Also, the diffusion coefficients were calculated by using the measured concentrations and the coefficients obtained from the field experiment were compared with the ones

Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain Site characterization study

International Nuclear Information System (INIS)

Dombrowski, T.; Stetzenbach, K.

1993-01-01

This report is in two parts one for the fluorinated benzoic acids and one for the fluorinated aliphatic acids. The assumptions made in the report regarding the amount of tracer that will be used, dilution of the tracer during the test and the length of exposure (if any) to individuals drinking the water were made by the authors. These assumptions must really come from the USGS hydrologists in charge of the c-well tracer testing program. Accurate estimates of dilution of the tracer during the test are also important because of solubility limitations of some of the tracers. Three of the difluorobenzoic acids have relatively low solubilities and may not be usable if the dilution estimates are large. The toxicologist that reviewed the document agreed with our conclusion that the fluorinated benzoic and toluic acids do not represent a health hazard if used under the conditions as outlined in the report. We are currently testing 15 of these compounds, and if even if three difluorobenzoic acids cannot be used because of solubility limitations we will still have 12 tracers. The toxicologist felt that the aliphatic fluorinated acids potentially present more of a health risk than the aromatic. This assessment was based on the fact of a known allergic response to halothane anesthetic. This risk, although minimal, is known and he felt that was enough reason to recommend against their use. The authors feel that the toxicologists interpretation of this risk was overly conservative, however, we will not go against his recommendation at this time for the following reasons. First, without the aliphatic compounds we still have 12 to 15 fluorinated aromatic acids which, should be enough for the c-well tests. Second, to get a permit to use aliphatic compounds would undoubtedly require a hearing which could be quite lengthy

Changes of the Specific Infectivity of Tracer Phages during Transport in Porous Media.

Science.gov (United States)

Ghanem, Nawras; Trost, Manuel; Sánchez Fontanet, Laura; Harms, Hauke; Chatzinotas, Antonis; Wick, Lukas Y

2018-03-20

Phages (i.e., viruses infecting bacteria) are considered to be good indicators and tracers for fecal pollution, hydraulic flow, or colloidal transport in the subsurface. They are typically quantified as total virus particles (VLP) or plaque forming units (PFU) of infectious phages. As transport may lead to phage deactivation, VLP quantification can overestimate the number of infectious phages. In contrast, PFU counts may underestimate the transport of total virus particles. Using PFU and tunable resistive pulse sensing-based counting for active and total phages, respectively, we quantified the effect of transport through laboratory percolation columns on the specific infectivity (SI). The SI is defined by the ratio of total VLP to PFU and is a measure for the minimum particle numbers needed to create a single infection. Transport of three marine tracer phages and the coli-phage (T4) was described by colloidal filtration theory. We found that apparent collision efficiencies of active and total phages differed. Depending on the phage properties (e.g., morphology or hydrophobicity), passage through a porous medium led to either an increasing or decreasing SI of effluent phages. Our data suggest that both phage mass recovery and the SI should be considered in quantitative phage tracer experiments.

3-D migration experiment - report 2: Instrumentation and tracers

International Nuclear Information System (INIS)

Abelin, H.; Birgersson, L.; Gidlund, J.

1987-11-01

This report is one of the four reports describing the Stripa 3D experiment where water and tracer flow has been monitored in a specially excavated drift in the Stripa mine. The experiment was performed in a specially excavated drift at the 360 m level in granite. The whole ceiling and upper part of the walls were covered with more than 350 individual plastic sheets where the water flow into the drift could be collected. 11 different tracers were injected at distances between 11 and 50 m from the ceiling of the drift. The flow rate and tracer monitoring was kept up for more than two years. The tracer breakthrough curves and flow rate distributions were used to study the flow paths, velocities, hydraulic conductivities, dispersivities and channeling effects in the rock. The report describes the instrumentation developed and used as well as the tracers that were tested and used in the experiment. (orig.)

Abdominal intra-compartment syndrome - a non-hydraulic model of abdominal compartment syndrome due to post-hepatectomy hemorrhage in a man with a localized frozen abdomen due to extensive adhesions: a case report.

Science.gov (United States)

Bressan, Alexsander K; Kirkpatrick, Andrew W; Ball, Chad G

2016-09-15

Postoperative hemorrhage is a significant cause of morbidity and mortality following liver resection. It typically presents early within the postoperative period, and conservative management is possible in the majority of cases. We present a case of late post-hepatectomy hemorrhage associated with overt abdominal compartment syndrome resulting from a localized functional compartment within the abdomen. A 68-year-old white man was readmitted with sudden onset of upper abdominal pain, vomiting, and hemodynamic instability 8 days after an uneventful hepatic resection for metachronous colon cancer metastasis. A frozen abdomen with adhesions due to complicated previous abdominal surgeries was encountered at the first intervention, but the surgery itself and initial recovery were otherwise unremarkable. Prompt response to fluid resuscitation at admission was followed by a computed tomography of his abdomen that revealed active arterial hemorrhage in the liver resection site and hemoperitoneum (estimated volume abdominal compartment syndrome. Surgical exploration confirmed a small volume of ascites and blood clots (1.2 L) under significant pressure in his supramesocolic region, restricted by his frozen lower abdomen, which we evacuated. Dramatic improvement in his ventilatory pressure was immediate. His abdomen was left open and a negative pressure device was placed for temporary abdominal closure. The fascia was formally closed after 48 hours. He was discharged home at postoperative day 6. Intra-abdominal pressure and radiologic findings of intra-abdominal hemorrhage should be carefully interpreted in patients with extensive intra-abdominal adhesions. A high index of suspicion and detailed understanding of abdominal compartment mechanics are paramount for the timely diagnosis of abdominal compartment syndrome in these patients. Clinicians should be aware that abnormal anatomy (such as adhesions) coupled with localized pathophysiology (such as hemorrhage) can create a so

Correlation of aeolian sediment transport measured by sand traps and fluorescent tracers

Science.gov (United States)

Cabrera, Laura L.; Alonso, Ignacio

2010-03-01

Two different methods, fluorescent tracers and vertical sand traps, were simultaneously used to carry out an aeolian sediment transport study designed to test the goodness of fluorescent tracers in aeolian environments. Field experiments were performed in a nebkha field close to Famara beach at Lanzarote Island (Canary Islands, Spain) in a sector where the dunes were between 0.5 and 0.8 m height and 1-2 m wide and the vegetal cover was approximately 22%. In this dune field the sediment supply comes from Famara beach and is blown by trade winds toward the south, where the vegetation acts as natural sediment traps. Wind data were obtained by means of four Aanderaa wind speed sensors and one Aanderaa vane, all them distributed in a vertical array from 0.1 to 4 m height for 27 h. The average velocity at 1 m height during the experiment was 5.26 m s - 1 with the wind direction from the north. The tracer was under wind influence for 90 min at midday. During this period two series of sand traps (T1 and T2) N, S, E and W oriented were used. Resultant transport rates were 0.0131 and 0.0184 kg m - 1 min - 1 respectively. Tracer collection was performed with a sticky tape to sample only surface sediments. Tagged grains were visually counted under UV light. The transport rate was computed from the centroid displacement, that moved 0.875 m southwards, and the depth of the active layer considered was the size of one single grain. Taking into account these data the transport rate was 0.0072 kg m - 1 min - 1 . The discrepancy in results between both methods is related to several factors, such as the thickness of the active layer and the grain size difference between the tagged and the native material.

Radioisotope tracers in industrial flow studies

International Nuclear Information System (INIS)

Easey, J.F.

1987-01-01

The scope of radioisotope tracer work carried out by ANSTO has involved most sectors of Australian industry including iron and steel coal, chemical, petrochemical, natural gas, metallurgical, mineral, power generation, liquified air plant, as well as port authorities, water and sewerage instrumentalities, and environmental agencies. A major class of such studies concerns itself with flow and wear studies involving industrial equipment. Some examples are discussed which illustrate the utility of radioisotope tracer techniques in these applications

Tracers Detect Aquifer Contamination

National Research Council Canada - National Science Library

Enfield, Carl

1995-01-01

The EPA's National Laboratory (NRMRL) at Ada, OK, along with the University of Florida and the University of Texas, have developed a tracer procedure to detect the amount of contamination in aquifer formations...

Feasibility of perfluorocarbon tracers (PFTs) in atmospheric source-receptor experiments

International Nuclear Information System (INIS)

Dietz, R.N.; Senum, G.I.

1984-03-01

A brief description of the perfluorocarbon tracer (PFT) system, which includes the tracers and the release equipment, the air samplers and the analyzers, is presented along with details on the research needs to provide a viable system for MATEX-scenario experiments. The present family of 2 viable PFTs needs to be increased to 5 to 6. Given the present precision of the analysis system, a one year long tracer experiment consisting of 4 hour releases every 60 hours from 5 different sites would require nearly 150 metric tons of PFTs at a cost of $15,000,000. Shortcomings in the programmable sampler include the pump, the sampling sequence control flexibility, data storage and retrieval, and the lack of remote communication capability; sampler adsorbent studies are also needed. The analytical system, including the catalyst processing bed, the chromatography column resolution, and the linearity of the detector, is in need of significant improvement. A higher resolution analysis system could significantly reduce analysis time but, more importantly, reduce tracer requirements more than 10-fold, for a cost savings potential of more than $13,000,000. A model is presented to demonstrate the feasibility of tracer material balances. Assessment of earlier long-range tracer experiments indicates the need for possibly 400 ground sampling sites requiring $8 to $14 million worth of samplers for a one-year tracer experiment. As many as six aircraft would be needed to conduct airborne model validation and material balance studies for each tracer plume

Root zone effects on tracer migration in arid zones

International Nuclear Information System (INIS)

Tyler, S.W.; Walker, G.R.

1994-01-01

The study of groundwater recharge and soil water movement in arid regions has received increased attention in the search for safe disposal sites for hazardous wastes. In passing through the upper 1 to 2 m of most soil profiles, tracers indicative of recharge such as Cl, 2 H, 18 O, Br, 3 H, and 56 Cl are subjected to a wide range of processes not encountered deeper in the profile. This transition zone, where water enters as precipitation and leaves as recharge, is often ignored when environmental tracers are used to estimate deep soil water flux and recharge, yet its effect may be profound. In this work, we reexamine the processes of root extraction and its effect on the velocity and distribution of tracers. Examples are presented for idealized conditions, which show clearly the relation between the root zone processes and the deep drainage or recharge. The results indicate that, when recharge is small and root zone processes are not accounted for, tracer techniques can significantly overestimate recharge until the tracer has moved well below the root zone. By incorporating simple models of root zone processes, a clearer understanding of tracer distributions and a more accurate estimate of recharge can then be made. 11 refs., 9 figs

Tracer tests - possibilities and limitations. Experience from SKB fieldwork: 1977-2007

Energy Technology Data Exchange (ETDEWEB)

Loefgren, Martin; Crawford, James; Elert, Mark (Kemakta Konsult AB, Stockholm (SE))

2007-09-15

Tracer tests have played, and still play, a central role in investigations relating to the understanding of radionuclide retention processes in the field. At present there is a debate within the scientific community concerning how, and to what extent, tracer tests can be used to evaluate large-scale and long-term transport and retardation of radionuclides and other solutes of interest for Safety Assessment of repositories for spent nuclear fuel. In this report the SKB fieldwork on tracer tests performed at Swedish sites from 1977 to 2007 is described and discussed. Furthermore, the knowledge and process understanding evolved during the decades of radionuclide transport experiments and modelling within the SKB programme is summarised. One of the main objectives of this report is to discuss what data and knowledge can be extracted from different in situ tests in a robust fashion. Given the level of complexity associated with transport processes that may occur over the timescale of a tracer test, the utility of tracer tests is considered in the context of evidence-based interpretations of data which we characterise in the form of a sequence of questions of increasing complexity. The complexity of this sequence ranges from whether connection can be confirmed between injection and withdrawal points to whether quantitative data can be extrapolated from a tracer test to be subsequently used in Safety Assessment. The main findings of this report are that: Field scale tracer tests can confirm flow connectivity. Field scale tracer tests confirm the existence of retention. Field scale tracer tests alone can only broadly substantiate our process understanding. However, if performing extensive Site Characterisation and integrating the tracer test results with the full range of geoscientific information available, much support can be given to our process understanding. Field scale tracer tests can deliver the product of the material property group MPG and the F-factor, valid

Abdominal Pain

Science.gov (United States)

... I find more information and related topics? Functional Abdominal Pain (English, French or Spanish)—from The North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN). Gastro Kids , a ...

Hybrid tracers for sentinel node biopsy

International Nuclear Information System (INIS)

Van Den Berg, N. S.; Kleinjan, G. I.; Valdés-Olmos, R. A.; Buckle, T.; Van Leeuwen, F. I.; Klop, W. M.; Horenblas, S.; Van Der Poel, H. G.

2014-01-01

Conventional sentinel node (SN) mapping is performed by injection of a radiocolloid followed by lymphoscintigraphy to identify the number and location of the primary tumor draining lymph node(s), the so-called SN(s). Over the last decade research has focused on the introduction of new imaging agents that can further aid (surgical) SN identification. Different tracers for SN mapping, with varying sizes and isotopes have been reported, most of which have proven their value in a clinical setting. A major challenge lies in transferring this diagnostic information obtained at the nuclear medicine department to the operating theatre thereby providing the surgeon with (image) guidance. Conventionally, an intraoperative injection of vital blue dye or a fluorescence dye is given to allow intraoperative optical SN identification. However, for some indications, the radiotracer-based approach remains crucial. More recently, hybrid tracers, that contain both a radioactive and fluorescent label, were introduced to allow for direct integration of pre- and intraoperative guidance technologies. Their potential is especially high when they are used in combination with new surgical imaging modalities and navigation tools. Next to a description of the known tracers for SN mapping, this review discusses the application of hybrid tracers during SN biopsy and how the introduction of these new techniques can further aid in translation of nuclear medicine information into the operating theatre.

Use of (3H) and (125I) tracers in steroid radioimmunoassays

International Nuclear Information System (INIS)

Jeffcoate, S.L.

1975-01-01

The comparative use of 3 H and 125 I tracers in steroid radioimmunoassays will be discussed around the following points: - 3 H. Advantages: they can be purchased commercially and have a long shelf-life. Disadvantages: they may have reduced affinity for antibodies due to ''isotope effects''; the counting of β-emitters is more expensive and difficult; 3 H tracers are not available for all steroids. - 125 I. Advantages: gamma-counting is cheaper, simpler and more precise; 125 I tracers may have higher affinity for antibodies than unlabelled steroids; 125 I can be used to label any steroid. Disadvantages: 125 I tracers have a limited shelf-life (n.b. six months for 125 I histamine tracers). The high affinity of some tracers will be a big disadvantage if the unlabelled steroid cannot compete effectively

Systems approach to tracer data in groundwater hydrology

International Nuclear Information System (INIS)

Saxena, R.K.

1977-01-01

A brief review of current mathematical methods for the analysis of tracer data in groundwater hydrology has been given. The description of the hydrological cycle as a whole or in part, by a system (compartment) or sub-system under linear and stationary conditions is discussed. Basic concepts of transit time, residence time, their distributions in time and response characteristics of a system are outlined. From the knowledge of tracer input, output and systems response function for a generalised system, reservoir capacity and storage for given period can be estimated. Use of a time series model for environmental tracer data in discreet time scale aimed at the solution of hydrological problems e.g. mean transit time and reservoir capacity is also explored. It is concluded that the combination of tracer data with systems approach can go a long way in the study of some complex hydrological problems. (author)

Development of an active tracer of nanospheres for using in oil reservoir and environment

International Nuclear Information System (INIS)

Fonseca, Raquel Luiza Mageste

2017-01-01

Radiotracers have been widely used in various sectors of science and engineering in order to investigate the transport in porous media due to their easy detection, the use of very low mass and with nanotechnology allowing simple modifications of their properties and their surfaces Via coating or chemical alteration, and can effectively replace conventional radioactive organic markers, which usually decompose. With this in mind, four methods of silica-coated gold nanoparticles were produced for use as tracers in porous media. Gold beads were produced from HAuCl 4 solutions. 3H 2 O and as reducing agents, gamma irradiation (S0), sodium oleate (S1); Sodium citrate - C 6 H 5 Na 3 O 7 .2H 2 O (S2 + PVP); And C 6 H 5 Na 3 O 7 .2H 2 O plus gamma irradiation (S3). Sample S1 was prepared by mixing an aqueous solution of HAuCl 4 .3H 2 O (2 x 10 -3 mol L -1 ) with isopropyl alcohol (C 3 H 8 O, neat) plus Polyvinylpilorridone (PVP, stabilizing agent) followed by gamma irradiation (30 kGy dose); Sample S1 was prepared by mixing an aqueous solution of HAuCl 4 3H 2 O (0.1 mol L -1 ) plus sodium oleate (0,05 mol L -1 ), followed by heating at 80°C for 10 min; For sample S2 + PVP, an aqueous solution of HAuCl 4 was mixed. 3H 2 O (0.1 mol L -1 ) and sodium citrate (0.034 mol L -1 ) followed by heating at 90°C; and finally, sample S3 was prepared by mixing an aqueous solution of HAuCl 4 .3H 2 O (0.1 mol L -1 ) plus sodium citrate (0.034 mol L -1 ) followed by gamma irradiation (30 kGy). The gold nanospheres were confirmed by ultraviolet analysis, presenting wavelengths between 514 and 530 nm. The gold beads were coated with a silica layer via sol-gel reaction using solutions of ethanol (pure) or isopropyl alcohol with tetraethyl ortho-tosylate (TEOS, 98%) and ammonium hydroxide (NH 4 OH, 28.3%). Physical interaction (control of size distribution and coating thickness) were examined by transmission electron microscopy analysis and discussed to test the efficiency of this NP as a

Prevalence of obesity and abdominal obesity in the Lausanne population

Directory of Open Access Journals (Sweden)

Paccaud Fred

2008-09-01

Full Text Available Abstract Background Obesity can be defined using body mass index (BMI or waist (abdominal obesity. Little information exists regarding its prevalence and determinants in Switzerland. Hence, we assessed the levels of obesity as defined by BMI or waist circumference in a Swiss population-based sample. Methods Cross-sectional, population-based non-stratified random sample of 3,249 women and 2,937 men aged 35–75 years living in Lausanne, Switzerland. Overall participation rate was 41%. Results In men, the prevalences of overweight (BMI ≥25 kg/m2 and obesity (BMI ≥30 kg/m2 were 45.5% and 16.9%, respectively, higher than in women (28.3% and 14.3%, respectively. The prevalence of abdominal obesity (waist ≥102 in men and ≥88 cm in women was higher in women than in men (30.6% vs. 23.9%. Obesity and abdominal obesity increased with age and decreased with higher educational level in both genders. In women, the prevalence of obesity was lower among former and current smokers, whereas in men the prevalence of obesity was higher in former smokers but did not differ between current and never smokers. Multivariate analysis showed age to be positively related, and education and physical activity to be negatively related with obesity and abdominal obesity in both genders, whereas differential effects of smoking were found between genders. Conclusion The prevalence of abdominal obesity is higher than BMI-derived obesity in the Swiss population. Women presented with more abdominal obesity than men. The association between smoking and obesity levels appears to differ between genders.

Novel tracer for radiation treatment planning; Welche neuen PET-Tracer braucht die Strahlentherapie?

Energy Technology Data Exchange (ETDEWEB)

Schwarzenboeck, S.; Krause, B.J. [Rostock Univ. (Germany). Klinik fuer Nuklearmedizin; Herrmann, K.; Gaertner, F.; Souvatzoglou, M. [Technische Univ. Muenchen (Germany). Klinik fuer Nuklearmedizin; Klaesner, B. [Klinikum Bogenhausen, Muenchen (Germany). Inst. fuer Radiologie und Nuklearmedizin

2011-07-15

PET and PET/CT with innovative tracers gain increasing importance in diagnosis and therapy management, and radiation treatment planning in radio-oncology besides the widely established FDG. The introduction of [{sup 18}F]Fluorothymidine ([{sup 18}F]FLT) as marker of proliferation, [{sup 18}F]Fluoromisonidazole ([{sup 18}F]FMISO) and [{sup 18}F]Fluoroazomycin-Arabinoside ([{sup 18}F]FAZA) as tracer of hypoxia, [{sup 18}F]Fluoroethyltyrosine ([{sup 18}F]FET) and [{sup 11}C]Methionine for brain tumour imaging, [{sup 68}Ga]DOTATOC for somatostatin receptor imaging, [{sup 18}F]FDOPA for dopamine synthesis and radioactively labeled choline derivatives for imaging phospholipid metabolism have opened novel approaches to tumour imaging. Some of these tracers have already been implemented into radio-oncology: Amino acid PET and PET/CT have the potential to optimise radiation treatment planning of brain tumours through accurate delineation of tumour tissue from normal tissue, necrosis and edema. Hypoxia represents a major therapeutic problem in radiation therapy. Hypoxia imaging is very attractive as it may allow to increase the dose in hypoxic tumours potentially allowing for a better tumour control. Advances in hybrid imaging, i.e. the introduction of MR/PET, may also have an impact in radio-oncology through synergies related to the combination of molecular signals of PET and a high soft tissue contrast of MRI as well as functional MRI capabilities. (orig.)

Halon-1301, a new Groundwater Age Tracer

Science.gov (United States)

Beyer, Monique; van der Raaij, Rob; Morgenstern, Uwe; Jackson, Bethanna

2015-04-01

Groundwater dating is an important tool to assess groundwater resources in regards to direction and time scale of groundwater flow and recharge and to assess contamination risks and manage remediation. To infer groundwater age information, a combination of different environmental tracers, such as tritium and SF6, are commonly used. However ambiguous age interpretations are often faced, due to a limited set of available tracers and limitations of each tracer method when applied alone. There is a need for additional, complementary groundwater age tracers. We recently discovered that Halon-1301, a water soluble and entirely anthropogenic gaseous substance, may be a promising candidate [Beyer et al, 2014]. Halon-1301 can be determined along with SF6, SF5CF3 and CFC-12 in groundwater using a gas chromatography setup with attached electron capture detector developed by Busenberg and Plummer [2008]. Halon-1301 has not been assessed in groundwater. This study assesses the behaviour of Halon-1301 in water and its suitability as a groundwater age tracer. We determined Halon-1301 in 17 groundwater and various modern (river) waters sites located in 3 different groundwater systems in the Wellington Region, New Zealand. These waters have been previously dated with tritium, CFC-12, CFC-11 and SF6 with mean residence times ranging from 0.5 to over 100 years. The waters range from oxic to anoxic and some show evidence of CFC contamination or degradation. This allows us to assess the different properties affecting the suitability of Halon-1301 as groundwater age tracer, such as its conservativeness in water and local contamination potential. The samples are analysed for Halon-1301 and SF6simultaneously, which allows identification of issues commonly faced when using gaseous tracers such as contamination with modern air during sampling. Overall we found in the assessed groundwater samples Halon-1301 is a feasible new groundwater tracer. No sample indicated significantly elevated

Tests of regional elemental tracers of pollution aerosols. 1. Distinctness of regional signatures, stability during transport, and empirical validation

International Nuclear Information System (INIS)

Lowenthal, D.H.; Wunschel, K.R.; Rahn, K.A.

1988-01-01

The two major requirements for a successful regional tracer system are distinctness of signatures and stability of signatures during transport. Dissimilarity of the five regional signatures from eastern North America is shown by collinearity diagnostics and by apportionment of synthetic samples generated randomly. Stability of regional signatures during transport is shown first by use of tracer elements in coarse and fine aerosol to predict the maximum possible change of ratios from particle-size effects alone and then by examination of actual changes in signatures during transport from the Midwest to Underhill, VT. Two recent empirical validations of the tracer system are presented: qualitative agreement of pulses of mid-western aerosol in Vermont with pulses of perfluorocarbon tracer gas released in Ohio during CAPTEX '83 and reproduction of our three major northeastern and mid-western signatures by other investigators. The tracer system currently uses the seven elements As, Se, Sb, Zn, In, noncrustal Mn, and noncrustal V as measured by instrumental neutron activation

A Newborn With Abdominal Pain.

Science.gov (United States)

Alwan, Riham; Drake, Meredith; Gurria Juarez, Juan; Emery, Kathleen H; Shaaban, Aimen F; Szabo, Sara; Sobolewski, Brad

2017-11-01

A previously healthy 3-week-old boy presented with 5 hours of marked fussiness, abdominal distention, and poor feeding. He was afebrile and well perfused. His examination was remarkable for localized abdominal tenderness and distention. He was referred to the emergency department in which an abdominal radiograph revealed gaseous distention of the bowel with a paucity of gas in the pelvis. Complete blood cell count and urinalysis were unremarkable. His ongoing fussiness and abnormal physical examination prompted consultation with surgery and radiology. Our combined efforts ultimately established an unexpected diagnosis. Copyright © 2017 by the American Academy of Pediatrics.

Theoretical analysis of experimental tracer and interdiffusion data in Cu-Ni-Fe alloys

International Nuclear Information System (INIS)

Belova, I.V.; Murch, G.E.; Filipek, R.; Danielewski, M.

2005-01-01

In this paper, we present strategies to extract fundamental atomistic information from measured diffusion coefficients in a ternary alloy system. The strategies are exemplified with Cu-Ni-Fe alloys at 1271 K where recent extensive interdiffusion coefficients and tracer diffusion coefficients for all three components have become available. We develop new defining phenomenological expressions for the vacancy-wind factors in terms of the diffusion coefficients. We show that the measured tracer diffusion coefficients can be processed using the Manning and Moleko, Allnatt and Allnatt random alloy diffusion kinetics formalisms (with and without the assumption of the Gibbs-Duhem relation between the thermodynamic activities) to give jump frequencies, tracer correlation factors, vacancy-wind factors and phenomenological coefficients. It is shown for example that Cu is generally the most correlated component in its diffusion behavior and that the off-diagonal phenomenological coefficients can be as high as 64% of the smallest of the diagonal phenomenological coefficients. It is also shown that the Darken formalism (which ignores off-diagonal phenomenological coefficients) is in fact a reasonable approximation for expressing the diagonal phenomenological coefficients in terms of the tracer diffusion coefficients. It is then shown how the measured interdiffusivities can be processed with these formalisms to give tracer diffusivities, vacancy-wind factors and phenomenological coefficients. Finally, we show how a straightforward strategy starting with the Darken analysis that is then followed by the Manning or Moleko, Allnatt and Allnatt analysis can be used to gain access to the vacancy-wind factors and the off-diagonal phenomenological coefficients

Simultaneous extraction and concentration of water pollution tracers using ionic-liquid-based systems.

Science.gov (United States)

Dinis, Teresa B V; Passos, Helena; Lima, Diana L D; Sousa, Ana C A; Coutinho, João A P; Esteves, Valdemar I; Freire, Mara G

2017-07-29

Human activities are responsible for the release of innumerous substances into the aquatic environment. Some of these substances can be used as pollution tracers to identify contamination sources and to prioritize monitoring and remediation actions. Thus, their identification and quantification are of high priority. However, due to their presence in complex matrices and at significantly low concentrations, a pre-treatment/concentration step is always required. As an alternative to the currently used pre-treatment methods, mainly based on solid-phase extractions, aqueous biphasic systems (ABS) composed of ionic liquids (ILs) and K 3 C 6 H 5 O 7 are here proposed for the simultaneous extraction and concentration of mixtures of two important pollution tracers, caffeine (CAF) and carbamazepine (CBZ). An initial screening of the IL chemical structure was carried out, with extraction efficiencies of both tracers to the IL-rich phase ranging between 95 and 100%, obtained in a single-step. These systems were then optimized in order to simultaneously concentrate CAF and CBZ from water samples followed by HPLC-UV analysis, for which no interferences of the ABS phase-forming components and other interferents present in a wastewater effluent sample have been found. Based on the saturation solubility data of both pollution tracers in the IL-rich phase, the maximum estimated concentration factors of CAF and CBZ are 28595- and 8259-fold. IL-based ABS can be thus envisioned as effective pre-treatment techniques of environmentally-related aqueous samples for a more accurate monitoring of mixtures of pollution tracers. Copyright © 2017 Elsevier B.V. All rights reserved.

Acute abdomen in children due to extra-abdominal causes.

Science.gov (United States)

Tsalkidis, Aggelos; Gardikis, Stefanos; Cassimos, Dimitrios; Kambouri, Katerina; Tsalkidou, Evanthia; Deftereos, Savas; Chatzimichael, Athanasios

2008-06-01

Acute abdominal pain in children is a common cause for referral to the emergency room and for subsequent hospitalization to pediatric medical or surgical departments. There are rare occasions when the abdominal pain is derived from extra-abdominal organs or systems. The aim of the present study was to establish the most common extra-abdominal causes of acute abdominal pain. The notes of all children (1 month-14 years of age) examined for acute abdominal pain in the Accident and Emergency (A&E) Department of Alexandroupolis District University Hospital in January 2001-December 2005 were analyzed retrospectively. Demographic data, clinical signs and symptoms, and laboratory findings were recorded, as well as the final diagnosis and outcome. Of a total number of 28 124 children who were brought to the A&E department, in 1731 the main complaint was acute abdominal pain. In 51 children their symptoms had an extra-abdominal cause, the most frequent being pneumonia (n = 15), tonsillitis (n = 10), otitis media (n = 9), and acute leukemia (n = 5). Both abdominal and extra-abdominal causes should be considered by a pediatrician who is confronted with a child with acute abdominal pain.

Automated segmentation and recognition of abdominal wall muscles in X-ray torso CT images and its application in abdominal CAD

International Nuclear Information System (INIS)

Zhou, X.; Kamiya, N.; Hara, T.; Fujita, H.; Chen, H.; Yokoyama, R.; Hoshi, H.

2007-01-01

The information of abdominal wall is very important for the planning of surgical operation and abdominal organ recognition. In research fields of computer assisted radiology and surgery and computer-aided diagnosis, the segmentation and recognition of the abdominal wall muscles in CT images is a necessary pre-processing step. Due to the complexity of the abdominal wall structure and indistinctive in CT images, the automated segmentation of abdominal wall muscles is a difficult issue and has not been solved completely. We propose an approach to segment the abdominal wall muscles and divide it into three categories (front abdominal muscles including rectus abdominis; left and right side abdominal muscles including external oblique, internal oblique and transversus abdominis muscles) automatically. The approach, first, makes an initial classification of bone, fat, and muscles and organs based on the CT number. Then a layer structure is generated to describe the 3-D anatomical structures of human torso by stretching the torso region onto a thin-plate for easy recognition. The abdominal wall muscles are recognized on the layer structures using the spatial relations to the skeletal structure and CT numbers. Finally, the recognized regions are mapped back to the 3-D CT images using an inverse transformation of the stretching process. This method is applied to 20 cases of torso CT images and evaluations are based on visual comparison of the recognition results and the original CT images by an expert in anatomy. The results show that our approach can segment and recognize abdominal wall muscle regions effectively. (orig.)

Evaluation of the hemostatic state, carbohydrate and lipid metabolism in young women with abdominal obesity and hypertension

Directory of Open Access Journals (Sweden)

Veronika Andreevna Sumerkina

2015-09-01

Full Text Available Aim of this study was to determine the characteristics of the laboratory parameters of hemostasis, carbohydrate and lipid metabolism in women with metabolic syndrome, isolated abdominal obesity or with hypertension. Materials and methods. The study included 71 women aged 30 – 44 years and was conducted at laboratory study of hemostasis system, carbohydrate and lipid metabolism. Results. In women with abdominal obesity and arterial hypertension we found an increased levels of glucose, total cholesterol, LDL-C and triglycerides and a decrease in a concentration of HDL-C compared to healthy women. The study of hemostasis revealed prothrombotic changes in the form of activation of coagulation hemostasis and fibrinolysis system activity. Conclusions. The disorders of carbohydrate and lipid metabolism are very prevalent in young women with abdominal obesity and hypertension with every second woman meeting the criteria for the metabolic syndrome. The most pronounced signs of activation of blood coagulation markes was seen in women with abdominal obesity and hypertension. In women with the individual components of the metabolic syndrome there were no significant changes in carbohydrate and lipid metabolism, although we saw an early signs of activation of hemocoagulation.

Mast Cells in Abdominal Aortic Aneurysms

DEFF Research Database (Denmark)

Shi, Guo-Ping; Lindholt, Jes Sanddal

2013-01-01

Mast cells (MCs) are proinflammatory cells that play important roles in allergic responses, tumor growth, obesity, diabetes, atherosclerosis, and abdominal aortic aneurysm (AAA). Although the presence and function of MCs in atherosclerotic lesions have been thoroughly studied in human specimens......, in primary cultured vascular cells, and in atherosclerosis in animals, their role in AAA was recognized only recently. Via multiple activation pathways, MCs release a spectrum of mediators � including histamine, inflammatory cytokines, chemokines, growth factors, proteoglycans, and proteases � to activate...... neighboring cells, degrade extracellular matrix proteins, process latent bioactive molecules, promote angiogenesis, recruit additional inflammatory cells, and stimulate vascular cell apoptosis. These activities associate closely with medial elastica breakdown, medial smooth-muscle cell loss and thinning...

Performance Testing of Tracer Gas and Tracer Aerosol Detectors for use in Radionuclide NESHAP Compliance Testing

Energy Technology Data Exchange (ETDEWEB)

Fuehne, David Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lattin, Rebecca Renee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-06-28

The Rad-NESHAP program, part of the Air Quality Compliance team of LANL’s Compliance Programs group (EPC-CP), and the Radiation Instrumentation & Calibration team, part of the Radiation Protection Services group (RP-SVS), frequently partner on issues relating to characterizing air flow streams. This memo documents the most recent example of this partnership, involving performance testing of sulfur hexafluoride detectors for use in stack gas mixing tests. Additionally, members of the Rad-NESHAP program performed a functional trending test on a pair of optical particle counters, comparing results from a non-calibrated instrument to a calibrated instrument. Prior to commissioning a new stack sampling system, the ANSI Standard for stack sampling requires that the stack sample location must meet several criteria, including uniformity of tracer gas and aerosol mixing in the air stream. For these mix tests, tracer media (sulfur hexafluoride gas or liquid oil aerosol particles) are injected into the stack air stream and the resulting air concentrations are measured across the plane of the stack at the proposed sampling location. The coefficient of variation of these media concentrations must be under 20% when evaluated over the central 2/3 area of the stack or duct. The instruments which measure these air concentrations must be tested prior to the stack tests in order to ensure their linear response to varying air concentrations of either tracer gas or tracer aerosol. The instruments used in tracer gas and aerosol mix testing cannot be calibrated by the LANL Standards and Calibration Laboratory, so they would normally be sent off-site for factory calibration by the vendor. Operational requirements can prevent formal factory calibration of some instruments after they have been used in hazardous settings, e.g., within a radiological facility with potential airborne contamination. The performance tests described in this document are intended to demonstrate the reliable

[Clinical Approach to Abdominal Pain as Functional Origin].

Science.gov (United States)

Ryu, Han Seung; Choi, Suck Chei

2018-02-25

Abdominal pain is a common symptom that patients refer to a hospital. Organic causes should be differentiated in patients with abdominal pain and treatment should be administered in accordance with the causes. A meticulous history taking and physical examination are highly useful in making a diagnosis, and blood tests, imaging modalities, and endoscopy are useful for confirming diagnosis. However, in many cases, patients have functional disorders with no obvious abnormal findings obtained even if many diagnostic tests are performed. Patients with functional disorders usually complain the vague abdominal pain located in the center and other portions of the abdominal area. Although the most representative disease is irritable bowel syndrome, functional abdominal pain syndrome is currently researched as a new disease entity of functional abdominal pain. As various receptors related to functional abdominal pain have been discovered, drugs associated with those receptors are used to treat the disorders, and additional new drugs are vigorously developed. In addition, medical therapy with pharmacological or non-pharmacological psychiatric treatment is effective for treating functional abdominal pain.

Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain site characterization study. Final report

International Nuclear Information System (INIS)

Stetzenbach, K.; Farnham, I.

1996-01-01

Extensive tracer testing is expected to take place at the C-well complex in the Nevada Test Site as part of the Yucca Mountain Site Characterization Project. The C-well complex consists of one pumping well, C3, and two injection wells, C1 and C2 into which tracer will be introduced. The goal of this research was to provide USGS with numerous tracers to completed these tests. Several classes of fluorinated organic acids have been evaluated. These include numerous isomers of fluorinated benzoic acids, cinnamic acids, and salicylic acids. Also several derivatives of 2-hydroxy nicotinic acid (pyridone) have been tested. The stability of these compounds was determined using batch and column tests. Ames testing (mutagenicity/carcinogenicity) was conducted on the fluorinated benzoic acids and a literature review of toxicity of the fluorobenzoates and three perfluoro aliphatic acids was prepared. Solubilities were measured and method development work was performed to optimize the detection of these compounds. A Quality Assurance (QA) Program was developed under existing DOE and USGS guidelines. The program includes QA procedures and technical standard operating procedures. A tracer test, using sodium iodide, was performed at the C-well complex. HRC chemists performed analyses on site, to provide real time data for the USGS hydrologists and in the laboratories at UNLV. Over 2,500 analyses were performed. This report provides the results of the laboratory experiments and literature reviews used to evaluate the potential tracers and reports on the results of the iodide C-well tracer test

Identification and characterization of conservative organic tracers for use as hydrologic tracers for the Yucca Mountain site characterization study. Final report

Energy Technology Data Exchange (ETDEWEB)

Stetzenbach, K.; Farnham, I.

1996-06-01

Extensive tracer testing is expected to take place at the C-well complex in the Nevada Test Site as part of the Yucca Mountain Site Characterization Project. The C-well complex consists of one pumping well, C3, and two injection wells, C1 and C2 into which tracer will be introduced. The goal of this research was to provide USGS with numerous tracers to completed these tests. Several classes of fluorinated organic acids have been evaluated. These include numerous isomers of fluorinated benzoic acids, cinnamic acids, and salicylic acids. Also several derivatives of 2-hydroxy nicotinic acid (pyridone) have been tested. The stability of these compounds was determined using batch and column tests. Ames testing (mutagenicity/carcinogenicity) was conducted on the fluorinated benzoic acids and a literature review of toxicity of the fluorobenzoates and three perfluoro aliphatic acids was prepared. Solubilities were measured and method development work was performed to optimize the detection of these compounds. A Quality Assurance (QA) Program was developed under existing DOE and USGS guidelines. The program includes QA procedures and technical standard operating procedures. A tracer test, using sodium iodide, was performed at the C-well complex. HRC chemists performed analyses on site, to provide real time data for the USGS hydrologists and in the laboratories at UNLV. Over 2,500 analyses were performed. This report provides the results of the laboratory experiments and literature reviews used to evaluate the potential tracers and reports on the results of the iodide C-well tracer test.

Tritium and deuterium as water tracers in hydrologic systems. Completion report

International Nuclear Information System (INIS)

Stewart, G.L.; Stetson, J.R.

1975-05-01

A study was conducted to evaluate the suitability of deuterium and tritium as tracers to depict water and pollutant movement in porous media. This involved studying the interaction of these tracers with soil materials and evaluating this interaction in terms of retardation in tracer flow velocity, compared to bulk water flow. Previous work had suggested that tritium and deuterium interact with soils and are removed from tracer solution during flow. The data presented clearly show that a tracing front becomes diluted in tracer during infiltration into oven-dried soil. There appears to be very little difference between the degree of tritium and deuterium interaction. The source of interaction is demonstrated to be primarily hydroxyl associated with the clay minerals. These exchange sites are destroyed by heating soil to 70C which eliminates tracer loss during infiltration

Assessment of abdominal muscle function in individuals with motor-complete spinal cord injury above T6 in response to transcranial magnetic stimulation.

Science.gov (United States)

Bjerkefors, Anna; Squair, Jordan W; Chua, Romeo; Lam, Tania; Chen, Zhen; Carpenter, Mark G

2015-02-01

To use transcranial magnetic stimulation and electromyography to assess the potential for preserved function in the abdominal muscles in individuals classified with motor-complete spinal cord injury above T6. Five individuals with spinal cord injury (C5-T3) and 5 able-bodied individuals. Transcranial magnetic stimulation was delivered over the abdominal region of primary motor cortex during resting and sub-maximal (or attempted) contractions. Surface electromyography was used to record motor-evoked potentials as well as maximal voluntary (or attempted) contractions in the abdominal muscles and the diaphragm. Responses to transcranial magnetic stimulation in the abdominal muscles occurred in all spinal cord injury subjects. Latencies of muscle response onsets were similar in both groups; however, peak-to-peak amplitudes were smaller in the spinal cord injury group. During maximal voluntary (or attempted) contractions all spinal cord injury subjects were able to elicit electromyography activity above resting levels in more than one abdominal muscle across tasks. Individuals with motor-complete spinal cord injury above T6 were able to activate abdominal muscles in response to transcranial magnetic stimulation and during maximal voluntary (or attempted) contractions. The activation was induced directly through corticospinal pathways, and not indirectly by stretch reflex activations of the diaphragm. Transcranial magnetic stimulation and electromyography measurements provide a useful method to assess motor preservation of abdominal muscles in persons with spinal cord injury.

A Needle-Type p-i-n Junction Semiconductor Detector for In-Vivo Measurement of Beta Tracer Activity

Energy Technology Data Exchange (ETDEWEB)

Lauber, A; Rosencrantz, B

1964-10-15

A miniature detector probe has been developed for in-vivo detection of beta tracer activity. A lithium-drifted p-i-n detector shaped as a cylinder 0.9 mm in diameter and 3 mm long acts as the sensing element. The detector is encased in a stainless steel tube 50 mm long, fastened to a holder fitted with a miniature coaxial contact. The free end of the tube has a syringe-like, entirely tight tip. The steel tube has an outer diameter of 1.4 mm except for 10 mm at the free end where the outer diameter is 1.1 mm corresponding to a wall thickness of 005 mm. The detector is placed in the 1.1 mm part of the tube. The construction and the properties of the probe are described.

A Needle-Type p-i-n Junction Semiconductor Detector for In-Vivo Measurement of Beta Tracer Activity

International Nuclear Information System (INIS)

Lauber, A.; Rosencrantz, B.

1964-10-01

A miniature detector probe has been developed for in-vivo detection of beta tracer activity. A lithium-drifted p-i-n detector shaped as a cylinder 0.9 mm in diameter and 3 mm long acts as the sensing element. The detector is encased in a stainless steel tube 50 mm long, fastened to a holder fitted with a miniature coaxial contact. The free end of the tube has a syringe-like, entirely tight tip. The steel tube has an outer diameter of 1.4 mm except for 10 mm at the free end where the outer diameter is 1.1 mm corresponding to a wall thickness of 005 mm. The detector is placed in the 1.1 mm part of the tube. The construction and the properties of the probe are described

Analysis of some laboratory tracer runs in natural fissures

International Nuclear Information System (INIS)

Moreno, L.; Neretnieks, I.

1984-01-01

Tracer tests in natural fissures performed in the laboratory are analysed by means of fitting two different models. In the experiments, sorbing and non-sorbing tracers were injected into a natural fissure running parallel to the axis of a drill core. The models take into account advection, diffusion into the rock matrix, sorption onto the rock surface and dispersion. For the last mechanism, one of the models considers hydrodynamic dispersion while the other model assumes channeling dispersion. The models take into account time delays in the inlet and outlet channels. The dispersion characteristics and water residence time were determined from the experiments with non-sorbing tracers. Surface and volume sorption coefficients and data on diffusion into the rock matrix were determined for the sorbing tracers. The results are compared with values independently determined in the laboratory. Good agreement was obtained using either model. When these models are used for prediction of tracer transport over larger distances, the results will depend on the model. The model with channeling dispersion will show a greater dispersion than the model with hydrodynamic dispersion. (author)

Effects of a physiological GH pulse on interstitial glycerol in abdominal and femoral adipose tissue

DEFF Research Database (Denmark)

Gravhølt, C H; Schmitz, Ole; Simonsen, L

1999-01-01

.0005). Administration of GH induced an increase in interstitial glycerol in both abdominal and femoral adipose tissue (ANOVA: abdominal, P = 0. 04; femoral, P = 0.03). There was no overall difference in the response to GH in the two regions during the study period as a whole (ANOVA: P = 0.5), but during peak...... stimulation of lipolysis abdominal adipose tissue was, in absolute but not in relative terms, stimulated more markedly than femoral adipose tissue (ANOVA: P = 0. 03 from 45 to 225 min). Peak interstitial glycerol values of 253 +/- 37 and 336 +/- 74 micromol/l were seen after 135 and 165 min in femoral...... and abdominal adipose tissue, respectively. ATBF was not statistically different in the two situations (ANOVA: P = 0.7). In conclusion, we have shown that a physiological pulse of GH increases interstitial glycerol concentrations in both femoral and abdominal adipose tissue, indicating activated lipolysis...

Radionuclides as tracers

International Nuclear Information System (INIS)

Ganatra, R.D.

1992-01-01

Importance of radioisotopes in medicine is because of their two characteristics: their biological behaviour is identical to their stable counterparts, and because they are radioactive their emissions can be detected by a suitable instrument. All isotopes of iodine will behave in the same way and will concentrate in the thyroid gland. There is no way of detecting the stable, natural iodine in the thyroid gland, but the presence of radioactive iodine can be detected externally in vivo by a detector. Thus, the radioactive iodine becomes a tracer, a sport of a spy, which mimics the behaviour of natural iodine and relays information to a detector. The radioactive tracers are popular because of the ease with which they can be detected in vivo and the fact that the measurement of their presence in the body can be in quantitative terms. The measurement can be very accurate and sensitive. Whenever the measurements can be done in vivo, the information is obtained in dynamic terms, as it is happening, as if the physiological events become transparent

The fluorescent tracer experiment on Holiday Beach near Mugu Canyon, Southern California

Science.gov (United States)

Kinsman, Nicole; Xu, J. P.

2012-01-01

After revisiting sand tracer techniques originally developed in the 1960s, a range of fluorescent coating formulations were tested in the laboratory. Explicit steps are presented for the preparation of the formulation evaluated to have superior attributes, a thermoplastic pigment/dye in a colloidal mixture with a vinyl chloride/vinyl acetate copolymer. In September 2010, 0.59 cubic meters of fluorescent tracer material was injected into the littoral zone about 4 kilometers upcoast of Mugu submarine canyon in California. The movement of tracer was monitored in three dimensions over the course of 4 days using manual and automated techniques. Detailed observations of the tracer's behavior in the coastal zone indicate that this tracer successfully mimicked the native beach sand and similar methods could be used to validate models of tracer movement in this type of environment. Recommendations including how to time successful tracer studies and how to scale the field of view of automated camera systems are presented along with the advantages and disadvantages of the described tracer methodology.

Investigation of Abdominal and General Obesity and Its Related Factors in students of Qom City, 2015, Iran

Directory of Open Access Journals (Sweden)

Parisa Sarraf

2017-04-01

Full Text Available Background and Objectives: Abdominal and general obesities are greatly affected by diet and physical activities. Prevalence of this complication in communities has an increasing trend, so that even adolescents are no exception in this regard. The current study aimed to investigate abdominal and general obesity and its related factors in’ students of Qom city. Methods: This cross-sectional study was conducted on 301 (17 girls and 114 boys students in medical and Azad universities in Qom city. These individuals were selected by proportional to size sampling method and studied by anthropometric measures, international short physical activity questionnaire, and 11-item nutritional habits questionnaire. Data were analyzed by independent t-, chi-square, and correlation coefficient tests. The significance level was considered to be α=0.05. Results: The mean BMI and WHR in students was 22.6±3.2kg/m2 and 0.8±0.0, respectively. A significant direct correlation was observed between anthropometric measures and abdominal obesity. Only 23.3% of the students had regular sport activity, so that the mean light physical activity in obese students was lower than normal students (38.9±43.1 vs. 60.8±67.5min. No heavy physical activity was seen in this group, and fast-food consumption was higher in this group of students compared to the normal students (93.2% vs. 67.8%. Conclusion: According to the findings of this study, there is a significant relationship between nutritional status and level of physical activity and abdominal and general obesity. Therefore, overweight, abdominal, and general obesity were lower in male students, and subjects involved in regular physical activity and lower fast-food consumption.

Effect of abdominal resistance exercise on abdominal subcutaneous fat of obese women: a randomized controlled trial using ultrasound imaging assessments.

Science.gov (United States)

Kordi, Ramin; Dehghani, Saeed; Noormohammadpour, Pardis; Rostami, Mohsen; Mansournia, Mohammad Ali

2015-01-01

The aim of this study was to compare the effect of diet and an abdominal resistance training program to diet alone on abdominal subcutaneous fat thickness and waist circumference of overweight and obese women. This randomized clinical trial included 40 overweight and obese women randomly divided into 2 groups: diet only and diet combined with 12 weeks of abdominal resistance training. Waist and hip circumferences and abdominal skin folds of the subjects were measured at the beginning and 12 weeks after the interventions. In addition, abdominal subcutaneous fat thickness of the subjects was measured using ultrasonography. Percentage body fat and lean body mass of all the subjects were also measured using a bioelectric impedance device. After 12 weeks of intervention, the weight of participants in both groups decreased; but the difference between the 2 groups was not significant (P = .45). Similarly, other variables including abdominal subcutaneous fat, waist circumference, hip circumference, body mass index, body fat percentage, and skin fold thickness were reduced in both groups; but there were no significant differences between the groups. This study found that abdominal resistance training besides diet did not reduce abdominal subcutaneous fat thickness compared to diet alone in overweight or obese women. Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

Enhanced Oil Recovery: Aqueous Flow Tracer Measurement

Energy Technology Data Exchange (ETDEWEB)

Joseph Rovani; John Schabron

2009-02-01

A low detection limit analytical method was developed to measure a suite of benzoic acid and fluorinated benzoic acid compounds intended for use as tracers for enhanced oil recovery operations. Although the new high performance liquid chromatography separation successfully measured the tracers in an aqueous matrix at low part per billion levels, the low detection limits could not be achieved in oil field water due to interference problems with the hydrocarbon-saturated water using the system's UV detector. Commercial instrument vendors were contacted in an effort to determine if mass spectrometry could be used as an alternate detection technique. The results of their work demonstrate that low part per billion analysis of the tracer compounds in oil field water could be achieved using ultra performance liquid chromatography mass spectrometry.

Dynamics and mechanics of bed-load tracer particles

Directory of Open Access Journals (Sweden)

C. B. Phillips

2014-12-01

Full Text Available Understanding the mechanics of bed load at the flood scale is necessary to link hydrology to landscape evolution. Here we report on observations of the transport of coarse sediment tracer particles in a cobble-bedded alluvial river and a step-pool bedrock tributary, at the individual flood and multi-annual timescales. Tracer particle data for each survey are composed of measured displacement lengths for individual particles, and the number of tagged particles mobilized. For single floods we find that measured tracer particle displacement lengths are exponentially distributed; the number of mobile particles increases linearly with peak flood Shields stress, indicating partial bed load transport for all observed floods; and modal displacement distances scale linearly with excess shear velocity. These findings provide quantitative field support for a recently proposed modeling framework based on momentum conservation at the grain scale. Tracer displacement is weakly negatively correlated with particle size at the individual flood scale; however cumulative travel distance begins to show a stronger inverse relation to grain size when measured over many transport events. The observed spatial sorting of tracers approaches that of the river bed, and is consistent with size-selective deposition models and laboratory experiments. Tracer displacement data for the bedrock and alluvial channels collapse onto a single curve – despite more than an order of magnitude difference in channel slope – when variations of critical Shields stress and flow resistance between the two are accounted for. Results show how bed load dynamics may be predicted from a record of river stage, providing a direct link between climate and sediment transport.

Economics of abdominal wall reconstruction.

Science.gov (United States)

Bower, Curtis; Roth, J Scott

2013-10-01

The economic aspects of abdominal wall reconstruction are frequently overlooked, although understandings of the financial implications are essential in providing cost-efficient health care. Ventral hernia repairs are frequently performed surgical procedures with significant economic ramifications for employers, insurers, providers, and patients because of the volume of procedures, complication rates, the significant rate of recurrence, and escalating costs. Because biological mesh materials add significant expense to the costs of treating complex abdominal wall hernias, the role of such costly materials needs to be better defined to ensure the most cost-efficient and effective treatments for ventral abdominal wall hernias. Copyright © 2013 Elsevier Inc. All rights reserved.

Perforated peptic ulcer associated with abdominal compartment syndrome.

Science.gov (United States)

Lynn, Jiun-Jen; Weng, Yi-Ming; Weng, Chia-Sui

2008-11-01

Abdominal compartment syndrome (ACS) is defined as an increased intra-abdominal pressure with adverse physiologic consequences. Abdominal compartment syndrome caused by perforated peptic ulcer is rare owing to early diagnosis and management. Delayed recognition of perforated peptic ulcer with pneumoperitoneum, bowel distension, and decreased abdominal wall compliance can make up a vicious circle and lead to ACS. We report a case of perforated peptic ulcer associated with ACS. A 74-year-old man with old stroke and dementia history was found to have distended abdomen, edema of bilateral legs, and cyanosis. Laboratory tests revealed deterioration of liver and kidney function. Abdominal compartment syndrome was suspected, and image study was arranged to find the cause. The study showed pneumoperitoneum, contrast stasis in heart with decreased caliber of vessels below the abdominal aortic level, and diffuse lymphedema at the abdominal walls. Emergent laparotomy was performed. Perforated peptic ulcer was noted and the gastrorrhaphy was done. The symptoms, and liver and kidney function improved right after emergent operation.

Methods for conduct of atmospheric tracer studies at ANSTO

Energy Technology Data Exchange (ETDEWEB)

Clark, G H; Stone, D J.M.; Pascoe, J H [Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia). Environment Division

2000-07-01

A perfluorocarbon atmospheric tracer system has been developed to investigate atmospheric dispersion processes in the region surrounding the Lucas Heights Science and Technology Centre. This report discusses the tracer release, sampling and analysis methods.

Imaging in Tuberculosis abdominal

International Nuclear Information System (INIS)

Suarez, Tatiana; Garcia, Vanessa; Tamara, Estrada; Acosta, Federico

2010-01-01

In this article we illustrate and discuss imaging features resulting from Tuberculosis abdominal affectation. We present patients evaluated with several imaging modalities who had abdominal symptoms and findings suggestive of granulomatous disease. Diagnosis was confirm including hystopatology and clinical outgoing. Cases involved presented many affected organs such as lymphatic system, peritoneum, liver, spleen, pancreas, kidneys, ureters, adrenal glands and pelvic organs Tuberculosis, Tuberculosis renal, Tuberculosis hepatic, Tuberculosis splenic Tomography, x-ray, computed

Arnebia euchroma ointment can reduce abdominal fat thickness and abdominal circumference of overweight women: A randomized controlled study.

Science.gov (United States)

Siavash, Mansour; Naseri, Mohsen; Rahimi, Mojgan

2016-01-01

Obesity is a worldwide health problem which is associated with a lot of complications. One of these comorbidities is the metabolic syndrome that is in correlation with abdominal fat thickness and waist circumference. Various methods were used to reduce abdominal fat thickness such as liposuction. A noninvasive method is the topical agent. In this study, we investigated the effectiveness of Arnebia euchroma (AE) ointment on the abdominal fat thickness. This study was a double-blind clinical trial which was done at the endocrinology clinic in Khorshid Hospital, Isfahan, Iran, in 2014. After explaining the procedure and obtaining informed consent, the candidates were randomly divided into the case and control groups. The participants of the case and control groups applied AE ointment or placebo for 6 weeks on their abdominal area. Body mass index, waist and buttock circumference, and abdominal fat thickness were measured in both case and control groups at their first visit and then at the next 2, 4, and 6 weeks. We used t -test for comparing parametric variables between groups, paired t -test for changes from baseline to final, and repeated measure ANOVA for changes at different steps. Sixty female candidates participated in this study (thirty in each group). Ten patients left the study and fifty participants finished the trial. At the end of the study, participants had a significant weight loss (2.96 ± 1.6 kg, P Abdominal circumference also decreased significantly in the participants (11.3 ± 6.7 cm, P abdominal fat thickness decreased significantly in the participants (2.3 ± 1.1 cm, P abdominal fat thickness as well as the waist circumference without causing any side effect.

Child abdominal tumour in tropical context: Think about schistosomiasis!

Directory of Open Access Journals (Sweden)

A. M. Napon

2014-01-01

Full Text Available Schistosomiasis presenting as an abdominal mass with chronic pain in a child is not common. This report presents case of child presenting with schistosomiasis presenting as an abdominal mass with chronic pain. Abdominal ultrasonography did not particularly contribute to definitive pre-operative diagnosis. However, pathological examination of surgical specimen confirmed Schistosoma mansoni eggs in the biospy. A decrease in the mass volume was noticed under medical treatment (Biltricide. The aim of this report was to intimate clinicians on possible abdominal schistosomiasis as differential diagnosis of childhood abdominal mass. This is a clarion call for a high index of suspicion of childhood abdominal schistosomiasis in children presenting with abdominal mass in a tropical setting.

Soft-tissue masses in the abdominal wall

International Nuclear Information System (INIS)

Bashir, U.; Moskovic, E.; Strauss, D.; Hayes, A.; Thway, K.; Pope, R.; Messiou, C.

2014-01-01

Masses involving the abdominal wall arise from a large number of aetiologies. This article will describe a diagnostic approach, imaging features of the most common causes of abdominal wall masses, and highly specific characteristics of less common diseases. A diagnostic algorithm for abdominal wall masses combines clinical history and imaging appearances to classify lesions

Quantifying solute transport processes: are chemically "conservative" tracers electrically conservative?

Science.gov (United States)

Singha, Kamini; Li, Li; Day-Lewis, Frederick D.; Regberg, Aaron B.

2012-01-01

The concept of a nonreactive or conservative tracer, commonly invoked in investigations of solute transport, requires additional study in the context of electrical geophysical monitoring. Tracers that are commonly considered conservative may undergo reactive processes, such as ion exchange, thus changing the aqueous composition of the system. As a result, the measured electrical conductivity may reflect not only solute transport but also reactive processes. We have evaluated the impacts of ion exchange reactions, rate-limited mass transfer, and surface conduction on quantifying tracer mass, mean arrival time, and temporal variance in laboratory-scale column experiments. Numerical examples showed that (1) ion exchange can lead to resistivity-estimated tracer mass, velocity, and dispersivity that may be inaccurate; (2) mass transfer leads to an overestimate in the mobile tracer mass and an underestimate in velocity when using electrical methods; and (3) surface conductance does not notably affect estimated moments when high-concentration tracers are used, although this phenomenon may be important at low concentrations or in sediments with high and/or spatially variable cation-exchange capacity. In all cases, colocated groundwater concentration measurements are of high importance for interpreting geophysical data with respect to the controlling transport processes of interest.

A radioactive tracer dilution method to determine the mass of molten salt

International Nuclear Information System (INIS)

Lei Cao; Jarrell, Josh; Hardtmayer, D.E.; White, Susan; Herminghuysen, Kevin; Kauffman, Andrew; Sanders, Jeff; Li, Shelly

2017-01-01

A new technique for molten salt mass determination, termed radioactive tracer dilution, that uses 22 Na as a tracer was validated at bench scale. It has been a challenging problem to determine the mass of molten salt in irregularly shaped containers, where a highly radioactive, high-temperature molten salt was used to process nuclear spent/used fuel during electrochemical recycling (pyro-processing) or for coolant/fuel salt from molten salt reactors. A radioactive source with known activity is dissolved into the salt. After a complete mixture, a small amount of the salt is sampled and measured in terms of its mass and radioactivity. By finding the ratio of the mass to radioactivity, the unknown salt mass in the original container can be precisely determined. (author)

Molecular dynamics investigation of tracer diffusion in a simple liquid

International Nuclear Information System (INIS)

Ould-Kaddour, F.; Barrat, J.L.

1991-05-01

Extensive Molecular-Dynamics (MD) simulations have been carried out for a model trace-solvent system made up of 100 solvent molecules and 8 tracer molecules interacting through truncated Lennard-Jones potentials. The influence of the size ratio between solute and solvent, of their mass ratio and of the solvent viscosity on the diffusivity of a small tracer were investigated. Positive deviations from a Stokes-Einstein behaviour are observed, in qualitative agreement with experimental observations. It was also observed that as tracer and solvent become increasingly dissimilar, their respective dynamics becomes decoupled. We suggest that such decouplings can be interpreted by writing their mobility of the tracer as the sum of two terms, the first one arising from a coupling between tracer dynamics and hydrodynamics modes of the solvent, and the second one describing jump motion in a locally nearly frozen environment. (author). 17 refs, 4 figs, 6 tabs

Geologic flow characterization using tracer techniques

International Nuclear Information System (INIS)

Klett, R.D.; Tyner, C.E.; Hertel, E.S. Jr.

1981-04-01

A new tracer flow-test system has been developed for in situ characterization of geologic formations. This report describes two sets of test equipment: one portable and one for testing in deep formations. Equations are derived for in situ detector calibration, raw data reduction, and flow logging. Data analysis techniques are presented for computing porosity and permeability in unconfined isotropic media, and porosity, permeability and fracture characteristics in media with confined or unconfined two-dimensional flow. The effects of tracer pulse spreading due to divergence, dispersion, and porous formations are also included

A comparison of measurements and calculations for the Stripa tracer experiments

International Nuclear Information System (INIS)

Hodgkinson, D.P.; Copper, N.S.

1992-03-01

This paper presents a comparison of measurements and predictions for migration of tracers from boreholes to the validation drift and to other boreholes in the Site Characterisation and Validation (SCV) block. The comparison was carried out on behalf of the Stripa task force on fracture flow modelling. The paper summarises the radar/saline tracer experiments, the tracer migration experiment observations and reviews the fracture flow and tracer transport modelling approaches and predictions made by AEA Technology, Fracflow Consultants, Golder Associates and Lawrence Berkeley Laboratory. The predictions are compared with the observed breakthrough curves on the basis of the validation process and criteria defined by the task force. The results of all four modelling groups met the validation criteria, with the predictions of the tracer breakthrough concentrations and times being within an order of magnitude of the observations. Also the AEA and Golder approaches allow the spatial distribution of tracer breakthrough into the validation drift to be predicted and these predictions also showed reasonable accuracy. The successful completion of this project demonstrates the feasibility of discrete fracture flow and tracer transport modelling. (36 refs.) (au)

Abdominal Compartment Syndrome in Surgical Patients

African Journals Online (AJOL)

abdominal hypertension and abdominal compartment syndrome, affect ... timely surgical intervention is crucial. Key words: .... On the second postoperative day, he was noted to be restless ... Although surgery is very effective in managing ACS.

Recurrent abdominal pain: when an epileptic seizure should be suspected? Dor abdominal recorrente: quando suspeitar de crise epiléptica?

Directory of Open Access Journals (Sweden)

Renata C. Franzon

2002-09-01

Full Text Available Recurrent episodes of abdominal pain are common in childhood. Among the diagnostic possibilities are migraine and abdominal epilepsy (AE. AE is an infrequent syndrome with paroxystic episodes of abdominal pain, awareness disturbance, EEG abnormalities and positive results with the introduction of antiepileptic drugs. We present one 6 year-old girl who had short episodes of abdominal pain since the age of 4. The pain was followed by cry, fear and occasionally secondary generalization. MRI showed tumor in the left temporal region. As a differential diagnosis, we report a 10 year-old boy who had long episodes of abdominal pain accompanied by blurring of vision, vertigo, gait ataxia, dysarthria, acroparesthesias and vomiting. He received the diagnosis of basilar migraine. In our opinion, AE is part of a large group (partial epilepsies and does not require a special classification. Pediatric neurologists must be aware of these two entities that may cause abdominal pain.Episódios recorrentes de dor abdominal são freqüentes na infância e entre as causas neurológicas há migrânea e epilepsia abdominal (EA. EA é uma síndrome que consiste de episódios paroxísticos de dor abdominal associada à alteração de consciência, anormalidades eletrencefalográficas e boa resposta à terapia anticonvulsivante. Apresentamos uma menina de 6 anos que tinha desde os 4 anos episódios de curta duração de dor abdominal, seguidos por choro, medo e ocasional generalização secundária. A RM mostrou a presença de um tumor em região temporal esquerda. Como diagnóstico diferencial, apresentamos um menino de 10 anos que há 12 meses referia episódios de dor abdominal de longa duração acompanhados por turvação visual, vertigem, marcha atáxica, disartria, acroparestesia e vômito, recebendo posteriormente o diagnóstico de migrânia basilar. Em nossa opinião, EA faz parte de um grande grupo (epilepsias parciais e não requer uma classificação especial

Consumo de bebida alcoólica e adiposidade abdominal em doadores de sangue Consumo de bebida alcohólica y adiposidad abdominal en donadores de sangre Alcohol consumption and abdominal fat in blood donors

Directory of Open Access Journals (Sweden)

Márcia Gonçalves Ferreira

2008-12-01

ón lineal múltiple, con los modelos ajustados para la edad, actividad física, tabaquismo y adiposidad total. RESULTADOS: Posterior al ajuste, la circunferencia de la cintura y la relación cintura/cuadril se mantuvieron asociados positivamente al consumo de cerveza (p=0,02 y al total de alcohol consumido (p=0,01 y 0,03, respectivamente. El consumo de aguardiente mostró asociación solamente con la circunferencia de la cintura (p=0,04. CONCLUSIONES: El consumo de alcohol, particularmente de cerveza, se asoció con la localización abdominal de gordura.OBJECTIVE: To evaluate the association between alcohol consumption and abdominal fat. METHODS: Cross-sectional study carried out in a sample of male blood donors (n=1,235, aged 20-59 years, in the city of Cuiabá, Central-West Brazil, between August 1999 and January 2000. Waist circumference and waist-to-hip ratio were indicators of abdominal fat, adjusted for total adiposity. Weight, height, waist and hip circumferences were measured. Alcohol consumption was evaluated using a questionnaire collecting information on type, frequency, and amount of consumption. The association between alcohol consumption and abdominal fat was assessed through multiple linear regression models adjusted for age, physical activity, smoking, and percent of body fat. RESULTS: After adjustment, waist circumference and waist-to-hip ratio were positively associated with beer (p = 0.02 and total alcohol consumption (p=0.01; p=0.03, respectively. Waist circumference was positively associated with spirit consumption (p=0.04. CONCLUSIONS: Alcohol intake, particularly beer, was positively associated to abdominal fat.

A new approach to tracer transport analysis: From fracture systems to strongly heterogeneous porous media

International Nuclear Information System (INIS)

Tsang, Chin-Fu.

1989-02-01

Many current development and utilization of groundwater resources include a study of their flow and transport properties. These properties are needed in evaluating possible changes in groundwater quality and potential transport of hazardous solutes through the groundwater system. Investigation of transport properties of fractured rocks is an active area of research. Most of the current approaches to the study of flow and transport in fractured rocks cannot be easily used for analysis of tracer transport field data. A new approach is proposed based on a detailed study of transport through a fracture of variable aperture. This is a two-dimensional strongly heterogeneous permeable system. It is suggested that tracer breakthrough curves can be analyzed based on an aperture or permeability probability distribution function that characterizes the tracer flow through the fracture. The results are extended to a multi-fracture system and can be equally applied to a strongly heterogeneous porous medium. Finally, the need for multi-point or line and areal tracer injection and observation tests is indicated as a way to avoid the sensitive dependence of point measurements on local permeability variability. 30 refs., 15 figs

Radiological evaluation of abdominal trauma

International Nuclear Information System (INIS)

Ahn, K. S.; Cho, Y. H.; Kim, O.

1982-01-01

Simple abdomen film has played an important role in decision of emergency operations in patients with the abdominal trauma. Nowadays, it still acts as a primary and inevitable processes in emergency condition. At the Department of Radiology, Hanil Hospital, 70 patients, who were laparotomied due to penetrating or nonpernetraing abdominal trauma, were observed and analyzed with simple abdomen film after comparison with the operative findings. The results are as follows: 1. Most frequent age distribution was 10 to 39 years and marked 70%. Male was in 90% incidence. 2. Penetrating injury largely involved the small bowel and abdominal wall. Non-penetrating injury usually involved the spleen, small bowel, liver, kidney, pancreas, duodenum. 3. Single organ injury occurred in higher incidence at the small bowel and abdominal wall. Multiple organ injury occurred in higher incidence at the spleen, liver, kidney and pancreas. 4. Organ distribution was 26% in spleen, 22% in small bowel, 14% in liver, 11% in abdominal wall. 7% in pancreas, 7% in kidney. 5% in duodenum, 4% in GB and CBD, 2% in diaphragm, 2% in colon, and 1% in stomach. 5. The specific roentgen findings and their frequency which useful in differential diagnosis at abdominal trauma, were as follows: a) flank fluid; Detectable possibility was 71% in liver laceration, 69% in spleen laceration and 57% in pancreas laceration. b) ipsilateral psoas shadow obliteration; Detectable possibility was 57% in liver laceration, 57% in kidney laceration and 46% in spleen laceration. c) free air; Detactable possibility was 60% in duodenal perforation, and 36% in peroration of upper part of small bowel. d) Reflex ileus; Detectable possibility was 64% in small bowel, 50% in liver laceration and 35% in spleen laceration. e) rib fracture; Detactable possibility was 36% in liver laceration and 23% in spleen laceration. f) pleural effusion; Detectable possibility was 29% in liver laceration and 27% in spleen laceration

Nanoparticle tracers in calcium carbonate porous media

KAUST Repository

Li, Yan Vivian

2014-07-15

Tracers are perhaps the most direct way of diagnosing subsurface fluid flow pathways for ground water decontamination and for natural gas and oil production. Nanoparticle tracers could be particularly effective because they do not diffuse away from the fractures or channels where flow occurs and thus take much less time to travel between two points. In combination with a chemical tracer they can measure the degree of flow concentration. A prerequisite for tracer applications is that the particles are not retained in the porous media as the result of aggregation or sticking to mineral surfaces. By screening eight nanoparticles (3-100 nm in diameter) for retention when passed through calcium carbonate packed laboratory columns in artificial oil field brine solutions of variable ionic strength we show that the nanoparticles with the least retention are 3 nm in diameter, nearly uncharged, and decorated with highly hydrophilic polymeric ligands. The details of these column experiments and the tri-modal distribution of zeta potential of the calcite sand particles in the brine used in our tests suggests that parts of the calcite surface have positive zeta potential and the retention of negatively charged nanoparticles occurs at these sites. Only neutral nanoparticles are immune to at least some retention. © 2014 Springer Science+Business Media.

Low-cost, High Flexibility I-V Curve Tracer for Photovoltaic Modules

DEFF Research Database (Denmark)

Ibirriaga, Julen Joseba Maestro; Pena, Xabier Miquelez de Mendiluce; Opritescu, Adrian

2010-01-01

This work presents the design, construction and test of an in-door low cost, high flexibility I-V curve tracer for photovoltaic modules. The tracer is connected to a Xenon lamp based flashing solar simulator. The designed tracer is able to deal with the very fast changing irradiation conditions...

Choice of infusion-sampling mode for tracer studies of free fatty acid metabolism

International Nuclear Information System (INIS)

Jensen, M.D.; Rogers, P.J.; Ellman, M.G.; Miles, J.M.

1988-01-01

To determine the preferred infusion-sampling mode for isotopic studies of free fatty acid (FFA) metabolism, tracer [( 14 C]palmitate) was infused into the left ventricle of five anesthetized dogs, and tracee ([ 3 H]palmitate) was infused into three separate peripheral veins of each dog. The [ 14 C]palmitate specific activity (SA) was lower in mixed venous than arterial blood, and [ 3 H]palmitate SA was equal in both sites. The actual infusion rate of [ 3 H]palmitate [2.15 +/- 0.31 X 10(5) disintegrations/min (dpm).kg-1.min-1] could be accurately predicted (2.14 +/- 0.32 X 10(5) dpm.kg-1.min-1) using the known [ 14 C]palmitate infusion rate and the arterial plasma [ 14 C]-to-[ 3 H]palmitate ratio. In contrast, the mixed venous [ 14 C]-to-[ 3 H]palmitate ratio resulted in overestimates (P less than 0.05) of the actual [ 3 H]palmitate infusion rate. In summary, venous tracer infusion with arterial blood sampling for FFA tracer studies provides the most accurate estimates of tracee rate of appearance

Effect of the Abdominal Hollowing and Bracing Maneuvers on Activity Pattern of the Lumbopelvic Muscles During Prone Hip Extension in Subjects With or Without Chronic Low Back Pain: A Preliminary Study.

Science.gov (United States)

Kahlaee, Amir H; Ghamkhar, Leila; Arab, Amir M

2017-02-01

The purpose of this study was to compare the effect of abdominal hollowing (AH) and abdominal bracing (AB) maneuvers on the activity pattern of lumbopelvic muscles during prone hip extension (PHE) in participants with or without nonspecific chronic low back pain (CLBP). Twenty women with or without CLBP participated in this cross-sectional observational study. The electromyographic activity (amplitude and onset time) of the contralateral erector spinae (CES), ipsilateral erector spinae (IES), gluteus maximus, and biceps femoris muscles was measured during PHE with and without abdominal maneuvers. A 3-way mixed model analysis of variance and post hoc tests were used for statistical analysis. Between-group comparisons showed that the CES onset delay during PHE alone was greater (P = .03) and the activity level of IES, CES, and biceps femoris in all maneuvers (P .05). Performance of the AH maneuver decreased the erector spinae muscle AMP in both groups, and neither maneuver altered the onset delay of any of the muscles in either group. The low back pain group showed higher levels of activity in all muscles (not statistically significant in gluteus maximus during all maneuvers). The groups were similar according to the onset delay of any of the muscles during either maneuver. Copyright © 2016. Published by Elsevier Inc.

Our experience of blood flow measurements using radioactive tracers

International Nuclear Information System (INIS)

Danet, Bernard.

1974-01-01

A critical study of blood flow measuring methods is proposed. After a review of the various diffusible and non-diffusible radioactive tracers and the corresponding detector systems, the principles which allow to measure blood flow from the data so obtained, are studied. There is a different principle of flow measurement for each type of tracer. The theory of flow measurement using non-diffusible tracers (human serum albumin labelled with 131 I or sup(99m)Tc, 113 In-labelled siderophiline) and its application to cardiac flow measurement are described first. Then the theory of flow measurement using diffusible tracers ( 133 Xe, 85 Kr) and its application to measurement of blood flow through tissues (muscles and kidney particularly) are described. A personal experience of this various flow measurements is reported. The results obtained, the difficulties encountered and the improvments proposed are developed [fr

Roentgenologic evaluation of blunt abdominal trauma

Energy Technology Data Exchange (ETDEWEB)

Lee, Yong Zoon; Ra, Woo Youn; Woo, Won Hyung [Hankang Sacred heart Hospital, Chung Ang University School of Medicine, Seoul (Korea, Republic of)

1974-10-15

This study comprises 25 cases of blunt abdominal trauma proved by surgery. It is concluded that visceral damage by blunt abdominal trauma may be suspected, but can not be satisfactorily diagnosed upon a single plane abdominal roentgenologic examination with clinical support. Contrary to some reports in the literature, rupture of the hallow, viscus is more susceptible than solid organ and ileum is more than jejunum. It is a useful roentgenologic sign denoting distension and small cresent air shadow in the duodenal sweep of the damaged pancreas.

The value of intra-abdominal pressure monitoring through ...

African Journals Online (AJOL)

hypertension after abdominal closure (8%) and only one of ... Ann Pediatr. Surg 13:69–73 c 2017 Annals of Pediatric Surgery. Annals of ... intra-abdominal hypertension ..... measurements as a guide in the closure of abdominal wall defects.

Analysis of infiltration through mill tailings using a bromide tracer

International Nuclear Information System (INIS)

Lewis, G.J.; Stephens, D.B.

1985-01-01

Infiltration of precipitation into tailings impoundments as a means of recharge to underlying materials is often considered insignificant, particularly in arid and semi-arid environments. A series of experiments was performed to investigate the behavior of infiltrated precipitation into tailing soils, by the use of a bromide tracer. A bromide tracer was applied to the surface of columns driven into the tailings to monitor downward advancement of tracer-laden water. Controlled laboratory experiments on the behavior of the bromide tracer under varying precipitation events and initial soil moisture contents were also conducted. Results indicate that a definite downward migration of infiltrated precipitation occurs, particularly with large magnitude precipitation events, and that, eventually, some fraction of the infiltrated precipitation may continue downward below the zone affected by evaporation. The use of an artificially applied bromide tracer to monitor depth of infiltration of precipitation is a simple, safe technique that can provide valuable information for long-term tailings management strategies at low cost

The efficacy of adhesiolysis on chronic abdominal pain

DEFF Research Database (Denmark)

Gerner-Rasmussen, Jonas; Burcharth, Jakob; Gögenur, Ismail

2015-01-01

INTRODUCTION: Abdominal adhesions are a frequent reason for chronic abdominal pain. The purpose of this systematic review was to investigate the evidence of performing laparoscopic adhesiolysis as a treatment for patients with chronic abdominal pain. METHODS: Medline, Embase, and The Cochrane Cen...... Central Register of Controlled Trials were searched for trials performing lysis of adhesions on patients suffering from chronic abdominal pain. Clinical studies on patients being treated for chronic abdominal pain with surgical adhesiolysis were included. The main outcome of the study...... chronic abdominal pain. A total of 22 trials were identified as case-series and included no control group. Three studies were identified as randomized controlled trials (RCT). A benefit of the intervention varied from 16 to 88 % in the non-randomized studies, with the majority reporting pain relief...... no difference between the intervention and control group. CONCLUSION: The identified studies showed promising but preliminary results of laparoscopic adhesiolysis as a treatment of chronic abdominal pain. The evidence for laparoscopic adhesiolysis is not sufficient to make definitive conclusions....

Slew-rate dependence of tracer magnetization response in magnetic particle imaging

Science.gov (United States)

Shah, Saqlain A.; Ferguson, R. M.; Krishnan, K. M.

2014-10-01

Magnetic Particle Imaging (MPI) is a new biomedical imaging technique that produces real-time, high-resolution tomographic images of superparamagnetic iron oxide nanoparticle tracers. Currently, 25 kHz and 20 mT/μ0 excitation fields are common in MPI, but lower field amplitudes may be necessary for patient safety in future designs. Here, we address fundamental questions about MPI tracer magnetization dynamics and predict tracer performance in future scanners that employ new combinations of excitation field amplitude (Ho) and frequency (ω). Using an optimized, monodisperse MPI tracer, we studied how several combinations of drive field frequencies and amplitudes affect the tracer's response, using Magnetic Particle Spectrometry and AC hysteresis, for drive field conditions at 15.5, 26, and 40.2 kHz, with field amplitudes ranging from 7 to 52 mT/μ0. For both fluid and immobilized nanoparticle samples, we determined that magnetic response was dominated by Néel reversal. Furthermore, we observed that the peak slew-rate (ωHo) determined the tracer magnetic response. Smaller amplitudes provided correspondingly smaller field of view, sometimes resulting in excitation of minor hysteresis loops. Changing the drive field conditions but keeping the peak slew-rate constant kept the tracer response almost the same. Higher peak slew-rates led to reduced maximum signal intensity and greater coercivity in the tracer response. Our experimental results were in reasonable agreement with Stoner-Wohlfarth model based theories.

Numerical Simulation of a Tracer Experiment at the Wolsong Nuclear Site

International Nuclear Information System (INIS)

Jeong, Hyojoon; Kim, Eunhan; Park, Misun; Jeong, Haesun; Hwang, Wontae; Han, Moonhee

2014-01-01

By comparing the concentration of a tracer measured under weather conditions that are disadvantageous to the dilution of radioactive materials released from the Wolsong Nuclear Power Plant, with the concentration of a tracer calculated using an air Dispersion model, it is possible to evaluate the characteristics of the air concentrations of radioactive materials estimated with an air Dispersion model, which can then be used in an environmental impact analysis of radioactive materials. Therefore, a field Dispersion experiment has been carried out to figure out the behavioral characteristics of the tracer under weather conditions that are disadvantageous to the dilution of radioactive materials released from the Wolsong Nuclear Power Plant site in Korea. In addition, through a comparison of the tracer concentrations estimated by the Gaussian plume model with measurements, this study checked the degree of conservative estimation for the Gaussian plume at the Wolsong nuclear site in Korea. A tracer Dispersion experiment using an SF 6 trace was implemented to determine the Dispersion characteristics of radioactive materials at the Wolsong Nuclear Power Plant site in Korea. Based on meteorological data and the emission rate of the tracers, this study estimated the tracer concentrations using a Gaussian plume model, and then compared it with the measurement to check the conservative estimation of the Gaussian plume model. The measured concentrations of the tracer tends to be lower than the concentrations estimated by the Gaussian plume model overall

Ecografía abdominal dedicada al trauma (FAST

Directory of Open Access Journals (Sweden)

Dr. O. Víctor Dinamarca

2013-01-01

El lavado peritoneal diagnóstico ha sido el gold standard para diagnóstico de hemoperitoneo, con una tasa de complicaciones de hasta un 10%. La ecografía abdominal focalizada para trauma abdominal o ecografía FAST (focused abdominal sonography for trauma es una herramienta accesible, portátil, no invasiva y confiable para el diagnóstico de la presencia o ausencia de líquido en el abdomen. Este artículo describe la técnica de la ecografía abdominal focalizada para el trauma abdominal cerrado, su utilización clínica, ventajas y limitaciones.

The use of bromine as a tracer for studying infiltrations in mining processes

International Nuclear Information System (INIS)

Diaz, F; Andonie, O; Rojas, X

2003-01-01

The impact of mining activity on underground water is becoming increasingly important because of the scarcity of the resource and due to the different use if there is water under the mining. Once the resource is affected the source of infiltration should be identified in all the processes and systems that are involved in the production system in order to take the appropriate preventive or remedial measures, which should also be the most efficient ones. Tracers play an important role in studying infiltration from mining processes to underground bodies of water. Natural chemical and isotopic tracers can identify the hydrogeological setting and help to establish supported hypotheses about the possible origin of the infiltrations. After the different ideas about the processes or systems that could be infiltrated are presented, the application of additional artificial tracers can resolve any doubts This work presents the use of bromine as a tracer for such studies, because of its specific characteristics as a good tracer in water with low interaction in porous surroundings, generally, and its determination by Neutron Activation Analyzers (NAA) due to its low limits of detection and the technique's precision and accuracy for use at reasonable costs. Given that for this type of study a large number of samples are necessary and that it should be carried out in a time period that does not surpass the duration of the process (a few months), a change had to be made in the methodology usually used for the NAA, which included taking a fraction of significantly less sample while meeting the power requirements for differentiating small changes in concentrations between samples. With this modification a larger number of samples can be irradiated in available positions for these purposes in the RECH-1 and the requirements for the number of samples and response time can be met. After the practical performance of this modification, a comparison between both methodologies was carried

Acute Abdomen Due to Uncontrolled Use of Warfarin: Spontaneous Intra-abdominal

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Fatih Dal

2017-12-01

Full Text Available Warfarin is an oral anticoagulant, which is commonly used in the treatment and prophylaxis of thromboembolic conditions. Bleeding is the primary adverse effect associated with warfarin. The majority of warfarin-related bleedings are spontaneous minor hemorrhages occurring in the subcutaneous or intramuscular tissues and can be treated by decreasing the dose of oral anticoagulants. However, although rare, it is possible to encounter spontaneous major bleedings with increased risk of mortality. Conservative approach is the preferred initial therapy for hemodynamically stable patients with major intra-abdominal hemorrhages that we define as the intermediate group patients. Nevertheless, surgery is required for hemodynamically unstable patients with acute abdominal pain in cases of ongoing active hemorrhage, generalized peritonitis, obstruction, acute abdomen, intestinal ischemia, and perforation. In this article, we present a rare case of acute abdomen and spontaneous intra-abdominal hemorrhage resulting from uncontrolled use of warfarin and a new classification requirement.

Development and application of an iridium tracer for tracking tailings in the central Red Sea

International Nuclear Information System (INIS)

Schnier, C.; Fanger, H.U.

1983-01-01

In order to investigate the distribution of disposed tailings, the element iridium was applied as a tracer during the prepilot mining test in the Red Sea 1979. In the sediment matrix, Ir can be detected in quantities as small as 25 x 10 -12 g by means of neutron activation analysis. The tracer was obtained by melting down a mixture of 50 kg quartz and 1 kg IrO 2 , then grinding and pulverizing the material to an appropriate grain size distribution. An amount of 480 m 3 tracer-added tailings was disposed in a depth of 400 m close to the Atlantis II deep. Subsequently, in the period 1 month to 2 1/2 years later, 32 sediment samples were taken from the deposition area and analysed for Ir. The Ir concentration observed were surprisingly low and give only vague indications of the spreading of the tailings. (orig.) [de

Estimation of the dilution field near a marine outfall by using effluent turbidity as an environmental tracer and comparison with dye tracer data.

Science.gov (United States)

Pecly, José Otavio Goulart

2018-01-01

The alternative use of effluent turbidity to determine the dilution field of a domestic marine outfall located off the city of Rio de Janeiro was evaluated through field work comprising fluorescent dye tracer injection and tracking with simultaneous monitoring of sea water turbidity. A preliminary laboratory assessment was carried out with a sample of the outfall effluent whose turbidity was measured by the nephelometric method before and during a serial dilution process. During the field campaign, the dye tracer was monitored with field fluorometers and the turbidity was observed with an optical backscattering sensor interfaced to an OEM data acquisition system. About 4,000 samples were gathered, covering an area of 3 km × 3 km near the outfall diffusers. At the far field - where a drift towards the coastline was observed - the effluent plume was adequately labeled by the dye tracer. The turbidity plume was biased due to the high and variable background turbidity of sea water. After processing the turbidity dataset with a baseline detrending method, the plume presented high correlation with the dye tracer plume drawn on the near dilution field. However, dye tracer remains more robust than effluent turbidity.