Use of electrocardiographic-thallium exercise testing in clinical practice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gitler, B.; Fishbach, M.; Steingart, R.M.

Although there is a great deal of data on the accuracy of combined electrocardiographic-thallium exercise testing, little is known about the use of these tests in clinical practice. A quantitative likelihood system was employed to characterize referral patterns for such testing, and the impact of test results on the likelihood of coronary artery disease was examined. Two hundred thirteen subjects consecutively referred for the purpose of establishing or excluding the presence of coronary artery disease were studied. No subject had a history of a prior myocardial infarction. By historical evaluation, 96 had a low likelihood of coronary disease (less thanmore » or equal to 0.20), 88 an intermediate likelihood (0.21 to 0.80) and 29 a high likelihood (greater than 0.80). As anticipated from theoretical analyses, testing produced the greatest shifts in disease likelihood in subjects with an intermediate pretest disease likelihood, and confirmed the historical evaluation in patients at the extremes of pretest disease likelihood. Therefore, although electrocardiographic-thallium stress testing is best suited for subjects with intermediate pretest disease likelihood, the majority of referrals had either a high or low likelihood. Clinicians appear to value confirmatory results in patients at the extremes of pretest disease likelihood. Electrocardiographic exercise testing would serve a similar purpose.« less

Physiologic abnormalities of cardiac function in progressive systemic sclerosis with diffuse scleroderma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Follansbee, W.P.; Curtiss, E.I.; Medsger, T.A. Jr.

1984-01-19

To investigate cardiopulmonary function in progressive systemic sclerosis with diffuse scleroderma, we studied 26 patients with maximal exercise and redistribution thallium scans, rest and exercise radionuclide ventriculography, pulmonary-function testing, and chest roentgenography. Although only 6 patients had clinical evidence of cardiac involvement, 20 had abnormal thallium scans, including 10 with reversible exercise-induced defects and 18 with fixed defects (8 had both). Seven of the 10 patients who had exercise-induced defects and underwent cardiac catheterization had normal coronary angiograms. Mean resting left ventricular ejection fraction and mean resting right ventricular ejection fraction were lower in patients with post-exercise left ventricular thalliummore » defect scores above the median (59 +/- 13 per cent vs. 69 +/- 6 per cent, and 36 +/- 12 per cent vs. 47 +/- 7 per cent, respectively). The authors conclude that in progressive systemic sclerosis with diffuse scleroderma, abnormalities of myocardial perfusion are common and appear to be due to a disturbance of the myocardial microcirculation. Both right and left ventricular dysfunction appear to be related to this circulatory disturbance, suggesting ischemically mediated injury.« less

SYNCHROTRON X-RAY ABSORPTION-EDGE COMPUTED MICROTOMOGRAPHY IMAGING OF THALLIUM COMPARTMENTALIZATION IN IBERIS INTERMEDIA

EPA Science Inventory

Thallium (TI) is an extremely toxic metal which, due to its similarities to K, is readily taken up by plants. Thallium is efficiently hyperaccumulated in Iberis intermedia as TI(I). Distribution and compartmentalization of TI in I. intermedia is highes...

Pharmacologic intervention as an alternative to exercise stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gould, K.L.

1987-04-01

Although thallium exercise imaging has served an important role in clinical cardiology, it is significantly limited by suboptimal sensitivity and specificity, particularly in asymptomatic man. The increasing recognition of silent myocardial ischemia, the significant prevalence of coronary artery disease in asymptomatic middle age men, and the frequent occurrence of myocardial infarction without preceding symptoms in 60% of cases emphasizes the need for a more definitive, noninvasive diagnostic test for the presence of coronary artery disease suitable for screening in asymptomatic or symptomatic patients. Intravenous dipyridamole combined with handgrip stress provides a potent stimulus for purposes of diagnostic perfusion imaging. Althoughmore » planar and single photon emission computed tomography (SPECT) imaging also have played an important role, these techniques are seriously hindered by their inability to quantitate radiotracer uptake or image modest differences in maximum relative flow caused by coronary artery stenosis. Accordingly, the combination of dipyridamole-handgrip stress with positron imaging of myocardial perfusion has become a powerful diagnostic tool suitable for routine clinical use. With the availability of generator-produced rubidium-82, dedicated clinically oriented positron cameras, the routine application of positron imaging to clinical cardiology has become feasible. 75 references.« less

Nuclear cardiology. I - Radionuclide angiographic assessment of left ventricular contraction: uses, limitations and future directions. II - The role of myocardial perfusion imaging using thallium-201 in diagnosis of coronary heart disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bodenheimer, M.M.; Banka, V.S.; Helfant, R.H.

1980-01-01

The current status of radionuclide angiography is reviewed. First pass and gated equilibrium methods for determining left ventricular contraction are compared. Some clinical applications of radionuclide angiography are then examined, including the detection of discrete versus diffuse asynergy and the assessment of myocardial infarction. The second part of this work reviews the uses and limitations of thallium-201 perfusion imaging in the diagnosis of the acute and chronic manifestations of coronary heart disease. Theoretical and technical considerations of thallium-201 imaging are reviewed along with the clinical implications of the technique.

Mineral resource of the month: thallium

USGS Publications Warehouse

Bi, Xiaoyu

2007-01-01

Thallium is known as a poison, its use initially suspected in the recent death of a Russian spy, but it has a variety of more important applications in everything from medical imaging to wireless communications.

The value and throughput of rest Thallium-201/stress Technetium -99m sestamibi dual-isotope myocardial SPECT.

PubMed

Okudan, Berna; Smitherman, Thomas C

2004-06-01

Myocardial perfusion scintigraphy is an established method in cardiology for the diagnosis and evaluation of coronary artery disease (CAD). Thallium-201 and Tc-99m sestamibi myocardial perfusion imaging has been widely accepted as non-invasive diagnostic procedure for detection of CAD, risk stratification and myocardial viability assessment. But, standard Tl-201 redistribution and same day or 2-day rest/stress Tc-99m sestamibi protocols are time-consuming. Hence, the dual isotope rest thallium-201/stress technetium-99m sestamibi gated single-photon emission tomography protocol has gained increasing popularity for these applications. Combining the use of thallium-201 with technetium-99m agents permits optimal image resolution and simultaneous assessment of viability. Dual-isotope imaging may be separate or simultaneous acquisition set-up. The more rapid completion of these studies is appreciated as an advantage by patients, technologists, interpreting and referring physicians, nurses and hospital management. Simultaneous imaging has the potential advantages of precise pixel registration and artifacts, if present, are identical in both thallium and sestamibi, and require only one set of imaging. Also, there are some disadvantages of spillover of activity from the Tc-99m to the Tl-201 window. Fortunately, despite this problem it can be overcome. Separate acquisition dual isotope also has some disadvantages. Difference in defect resolution in attenuation and scatter between T-201 and Tc-99m sestamibi potentially results in interpretation problems. But, studies about cost-effectiveness of dual isotope imaging showed that some selective elimination of the rest studies may decrease the cost of the nuclear procedures and should be considered in the current care health system.

IRIS Toxicological Review of Thallium and Compounds (External Review Draft)

EPA Science Inventory

Thallium compounds are used in the semiconductor industry, the manufacture of optic lenses and low-melting glass, low-temperature thermometers, alloys, electronic devices, mercury lamps, fireworks, and imitation germs, and clinically as an imaging agent in the diagnosis of certai...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stanton, M.S.; Tuli, M.M.; Radtke, N.L.

Transmural myocardial infarction in dogs produces denervation of sympathetic nerves in viable myocardium apical to the infarct that may be arrhythmogenic. It is unknown whether sympathetic denervation occurs in humans. The purpose of this study was to use iodine-123-metaiodobenzylguanidine (MIBG), a radiolabeled guanethidine analog that is actively taken up by sympathetic nerve terminals, to image noninvasively the cardiac sympathetic nerves in patients with and without ventricular arrhythmias after myocardial infarction. Results showed that 10 of 12 patients with spontaneous ventricular tachyarrhythmias after myocardial infarction exhibited regions of thallium-201 uptake indicating viable perfused myocardium, with no MIBG uptake. Such a findingmore » is consistent with sympathetic denervation. One patient had frequent episodes of nonsustained ventricular tachycardia induced at exercise testing that was eliminated by beta-adrenoceptor blockade. Eleven of the 12 patients had ventricular tachycardia induced at electrophysiologic study and metoprolol never prevented induction. Sympathetic denervation was also detected in two of seven postinfarction patients without ventricular arrhythmias. Normal control subjects had no regions lacking MIBG uptake. This study provides evidence that regional sympathetic denervation occurs in humans after myocardial infarction and can be detected noninvasively by comparing MIBG and thallium-201 images. Although the presence of sympathetic denervation may be related to the onset of spontaneous ventricular tachyarrhythmias in some patients, it does not appear to be related to sustained ventricular tachycardia induced at electrophysiologic study.« less

Psychological symptom profiles in patients with chest pain.

PubMed

Tennant, C; Mihailidou, A; Scott, A; Smith, R; Kellow, J; Jones, M; Hunyor, S; Lorang, M; Hoschl, R

1994-05-01

Five-hundred and thirty-two patients with ischaemic-like chest pain referred for symptom-limited exercise thallium myocardial perfusion studies, were assessed on a range of psychosocial measures. Three groups of patients were identified on the basis of their perfusion studies: (1) normal thallium perfusion; (2) current myocardial ischaemia; and (3) past myocardial infarction (but no current ischaemia). There were no significant psychological differences between these groups on a wide range of measures which included depression, state and trait anxiety, Type A behaviour, personality, suppression of affect, locus of control, alexythymia, and hypochondriasis. Significant differences were identified, however, on measures of anger and coping style. Subjects with no current ischaemia (normal thallium perfusion and those with past myocardial infarction) had higher scores on 'immature coping' and 'anger in', than subjects with current myocardial ischaemia. These findings are discussed in the light of other published research.

IRIS Toxicological Review of Thallium and Compounds ...

EPA Pesticide Factsheets

Thallium compounds are used in the semiconductor industry, the manufacture of optic lenses and low-melting glass, low-temperature thermometers, alloys, electronic devices, mercury lamps, fireworks, and imitation germs, and clinically as an imaging agent in the diagnosis of certain tumors. EPA's assessment of noncancer health effects and carcinogenic potential of thallium compounds was last prepared and added to the IRIS database between 1988 and 1990. The IRIS program is preparing an assessment that will incorporate current health effects information available for thallium and compounds, and current risk assessment methods. The IRIS assessment for thallium compounds will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physiochemical and toxicokinetic properties of a chemical, and its toxicity in humans and experimental systems. The assessment will present reference values for the noncancer effects of thallium compounds (RfD and Rfc), and a cancer assessment. The Toxicological Review and IRIS Summary have been subject to Agency review, Interagency review, and external scientific peer review. The final product will reflect the Agency opinion on the overall toxicity of thallium and compounds. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for thallium and compounds. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effec

Multiple coronary arterial loops as a cause of myocardial ischemia

NASA Technical Reports Server (NTRS)

Bashour, Tali T.; Mansour, Nagi N.; Lee, Damon

1993-01-01

A case of long-standing angina with ischemia documented by exercise testing and thallium scintigraphy in a patient who had multiple proximal loops in all three major coronary arteries in the absence of luminal stenosis, is reported.

Clinical results with beta-methyl-p-(123I)iodophenylpentadecanoic acid, single-photon emission computed tomography in cardiac disease.

PubMed

Nishimura, T; Uehara, T; Shimonagata, T; Nagata, S; Haze, K

1994-01-01

This study was undertaken to evaluate the relationships, between myocardial perfusion and metabolism. Simultaneous beta-methyl-p(123I)iodophenylpentadecanoic acid (123I-BMIPP) and thallium 201 myocardial single-photon emission computed tomography (SPECT) were performed in 25 patients with myocardial infarction (group A) and 16 patients with hypertrophic cardiomyopathy (group B). The severity scores of 123I-BMIPP and 201Tl myocardial SPECT images were evaluated semiquantitatively by segmental analysis. In Group A, dissociations between thallium- and 123I-BMIPP-imaged defects were frequently observed in patients with successful reperfusion compared with those with no reperfusion and those with reinfarction. In four patients with successful reperfusion, repeated 123I-BMIPP and 201Tl myocardial SPECT showed gradual improvement of the 123I-BMIPP severity score compared with the thallium severity score. In group B, dissociations between thallium- and 123I-BMIPP-imaged defects were also demonstrated in hypertrophic myocardium. In addition, nonhypertrophic myocardium also had decreased 123I-BMIPP uptake. In groups A and B, 123I-BMIPP severity scores correlated well with left ventricular function compared with thallium severity scores. These findings indicate that 123I-BMIPP is a suitable agent for the assessment of functional integrity, because left ventricular wall motion is energy dependent and 123I-BMIPP may reflect an aspect of myocardial energy production. This agent may be useful for the early detection and patient management of various heart diseases as an alternative to positron emission tomographic study.

Assessment of myocardial viability by dynamic tomographic iodine 123 iodophenylpentadecanoic acid imaging: comparison with rest-redistribution thallium 201 imaging.

PubMed

Iskandrian, A S; Powers, J; Cave, V; Wasserleben, V; Cassell, D; Heo, J

1995-01-01

This study examined the ability of dynamic 123I-labeled iodophenylpentadecanoic acid (IPPA) imaging to detect myocardial viability in patients with left ventricular (LV) dysfunction caused by coronary artery disease. Serial 180-degree single-photon emission computed tomographic (SPECT) images (five sets, 8 minutes each) were obtained starting 4 minutes after injection of 2 to 6 mCi 123I at rest in 21 patients with LV dysfunction (ejection fraction [EF] 34% +/- 11%). The segmental uptake was compared with that of rest-redistribution 201Tl images (20 segments/study). The number of perfusion defects (reversible and fixed) was similar by IPPA and thallium (11 +/- 5 vs 10 +/- 5 segments/patient; difference not significant). There was agreement between IPPA and thallium for presence or absence (kappa = 0.78 +/- 0.03) and nature (reversible, mild fixed, or severe fixed) of perfusion defects (kappa = 0.54 +/- 0.04). However, there were more reversible IPPA defects than reversible thallium defects (7 +/- 4 vs 3 +/- 4 segments/patient; p = 0.001). In 14 patients the EF (by gated pool imaging) improved after coronary revascularization from 33% +/- 11% to 39% +/- 12% (p = 0.002). The number of reversible IPPA defects was greater in the seven patients who had improvement in EF than in the patients without such improvement (10 +/- 4 vs 5 +/- 4 segments/patient; p = 0.075). 123I-labeled IPPA SPECT imaging is a promising new technique for assessment of viability. Reversible defects predict recovery of LV dysfunction after coronary revascularization.

Myocardial perfusion abnormalities in asymptomatic patients with systemic lupus erythematosus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hosenpud, J.D.; Montanaro, A.; Hart, M.V.

1984-08-01

Accelerated coronary artery disease and myocardial infarction in young patients with systemic lupus erythematosus is well documented; however, the prevalence of coronary involvement is unknown. Accordingly, 26 patients with systemic lupus were selected irrespective of previous cardiac history to undergo exercise thallium-201 cardiac scintigraphy. Segmental perfusion abnormalities were present in 10 of the 26 studies (38.5 percent). Five patients had reversible defects suggesting ischemia, four patients had persistent defects consistent with scar, and one patient had both reversible and persistent defects in two areas. There was no correlation between positive thallium results and duration of disease, amount of corticosteroid treatment,more » major organ system involvement or age. Only a history of pericarditis appeared to be associated with positive thallium-201 results (p less than 0.05). It is concluded that segmental myocardial perfusion abnormalities are common in patients with systemic lupus erythematosus. Whether this reflects large-vessel coronary disease or small-vessel abnormalities remains to be determined.« less

Feasibility of ultra low-dose thallium stress-redistribution protocol including prone imaging in obese patients using CZT camera.

PubMed

Kincl, Vladimír; Kamínek, Milan; Vašina, Jiří; Panovský, Roman; Havel, Martin

2016-09-01

High efficiency cadmium-zinc-telluride (CZT) cameras provide an opportunity to lower the injected activities of radiopharmaceuticals for single photon emission tomography (SPECT) myocardial perfusion imaging (MPI). The limits for reducing activities of thallium have not been determined, particularly in obese patients. After an injection of 0.7 megabecquerel (MBq) of thallium/kg, we collected an average 1.5 million counts for the 10-min acquisition in a pilot cohort of ten patients. After extrapolation, we reduced the administered activity to 0.5 MBq/kg to obtain the expected 1 million counts. We studied the image quality in 124 patients (86 men, 43 obese with body mass index over 30 kg/m 2 ) referred for MPI. The quality of images was assessed by a number of recorded counts and visually by a four-grade scale (one-poor quality, four-excellent quality). In non-obese and obese patients, the average number of recorded counts was 1.1 vs. 1.07 million counts for the 10-min stress acquisition, 1.04 vs. 1.06 million counts for the 13-min rest acquisition, and the average quality score was 3.97 vs. 3.90, respectively (p = NS).The mean administered activity was 39.2 ± 7 MBq for non-obese and 48.7 ± 6 for obese patients (p < 0.0001), and the calculated effective dose was 4.0 ± 0.7 and 4.9 ± 0.6 mSv respectively (p < 0.0001). The ultra-low-dose thallium stress-redistribution protocol, including post-stress prone imaging, provides good quality of images with a low radiation burden, even in obese patients.

Normalization of reverse redistribution of thallium-201 with procainamide pretreatment in Wolff-Parkinson-White syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nii, T.; Nakashima, Y.; Nomoto, J.

1991-03-01

Stress thallium-201 myocardial perfusion imaging was performed in a patient with Wolff-Parkinson-White syndrome. Reverse redistribution phenomenon was observed in the absence of coronary artery disease. This seems to be the first report of normalization of this phenomenon in association with reversion of accessory pathway to normal atrioventricular conduction after pretreatment with procainamide.

[Performance of Thallium 201 rest-redistribution spect to predict viability in recent myocardial infarction].

PubMed

Coll, Claudia; González, Patricio; Massardo, Teresa; Sierralta, Paulina; Humeres, Pamela; Jofré, Josefina; Yovanovich, Jorge; Aramburú, Ivonne; Brugère, Solange; Chamorro, Hernán; Ramírez, Alfredo; Kunstmann, Sonia; López, Héctor

2002-03-01

The detection of viability after acute myocardial infarction is primordial to select the most appropriate therapy, to decrease cardiac events and abnormal remodeling. Thallium201 SPECT is one of the radionuclide techniques used to detect viability. To evaluate the use of Thallium201 rest-redistribution SPECT to detect myocardial viability in reperfused patients after a recent myocardial infarction. Forty one patients with up to of 24 days of evolution of a myocardial infarction were studied. All had angiographically demonstrated coronary artery disease and were subjected to a successful thrombolysis, angioplasty or bypass grafting. SPECT Thallium201 images were acquired at rest and after 4 h of redistribution. These results were compared with variations in wall motion score, studied at baseline and after 3 or 4 months with echocardiography. The sensitivity of rest-redistribution Thallium201 SPECT, to predict recovery of wall motion was 91% when patient analysis was performed and 79% when segmental analysis was done in the culprit region. The figures for specificity were 56 and 73% respectively. Rest-distribution Thallium201 SPECT has an excellent sensitivity to predict myocardial viability in recent myocardial infarction. The data obtained in this study is similar to that reported for chronic coronary artery disease.

Normal results of post-race thallium-201 myocardial perfusion imaging in marathon runners with elevated serum MB creatine kinase levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siegel, A.J.; Silverman, L.M.; Holman, B.L.

1985-10-01

Elevated cardiac enzyme values in asymptomatic marathon runners after competition can arise from skeletal muscle through exertional rhabdomyolysis, silent injury to the myocardium, or a combined tissue source. Peak post-race levels of the MB isoenzyme of creatine kinase are similar to values in patients with acute myocardial infarction. Previously reported normal results of infarct-avid myocardial scintigraphy with technetium 99m pyrophosphate in runners after competition suggest a non-cardiac source but cannot exclude silent injury to the myocardium. Therefore, thallium 201 myocardial perfusion imaging was performed in runners immediately after competition together with determination of sequential cardiac enzyme levels. Among 15 runnersmore » tested, the average peak in serum MB creatine kinase 24 hours after the race was 128 IU/liter with a cumulative MB creatine kinase release of 117 IU/liter; these values are comparable to those in patients with acute transmural myocardial infarction. Thallium 201 myocardial scintigraphic results were normal in five runners randomly selected from those who volunteered for determination of sequential blood levels. It is concluded that elevations of serum MB creatine kinase in marathon runners arise from a skeletal muscle source and that thallium 201 myocardial scintigraphy is useful to assess runners for myocardial injury when clinical questions arise.« less

Electron microscopy study of antioxidant interaction with bacterial cells

NASA Astrophysics Data System (ADS)

Plotnikov, Oleg P.; Novikova, Olga V.; Konnov, Nikolai P.; Korsukov, Vladimir N.; Gunkin, Ivan F.; Volkov, Uryi P.

2000-10-01

To maintain native microorganisms genotype and phenotype features a lyophylization technique is widely used. However in this case cells are affected by influences of vacuum and low temperature that cause a part of the cells population to be destruction. Another factor reduced microorganisms vitality is formation of reactive oxygen forms that damage certain biological targets (such as DNA, membranes etc.) Recently to raise microorganism's resistance against adverse condition natural and synthetic antioxidants are used. Antioxidant- are antagonists of free radicals. Introduction of antioxidants in protective medium for lyophylization increase bacteria storage life about 2,0-4,8 fold in comparison with reference samples. In the article the main results of our investigation of antioxidants interaction with microorganism cells is described. As bacteria cells we use vaccine strain yersinia pestis EV, that were grown for 48 h at 28 degree(s)C on the Hottinger agar (pH 7,2). Antioxidants are inserted on the agar surface in specimen under test. To investigate a localization of antioxidants for electron microscopy investigation, thallium organic antioxidants were used. The thallium organic compounds have an antioxidant features if thallium is in low concentration (about 1(mu) g/ml). The localization of the thallium organic antioxidants on bacteria Y. pestis EV is visible in electron microscopy images, thallium being heavy metal with high electron density. The negatively stained bacteria and bacteria thin sections with thallium organic compounds were investigated by means of transmission electron microscopy. The localization of the thallium organic compounds is clearly visible in electron micrographs as small dark spots with size about 10-80nm. Probably mechanisms of interaction of antioxidants with bacteria cells are discussed.

Parathyroid adenoma associated with neurofibromatosis: Correlative scintigraphic and magnetic resonance imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vogelzang, P.J.; Oates, E.; Bankoff, M.S.

Correlative imaging by dual-isotope thallium/technetium subtraction scintigraphy, computed tomography, and magnetic resonance imaging demonstrated a pathologically proven parathyroid adenoma in a 62-year-old man with known neurofibromatosis, who presented with hypercalcemia and an elevated parathormone level. The association between neurofibromatosis and primary hyperparathyroidism is discussed.

Comparison of conventional and cadmium-zinc-telluride single-photon emission computed tomography for analysis of thallium-201 myocardial perfusion imaging: an exploratory study in normal databases for different ethnicities.

PubMed

Ishihara, Masaru; Onoguchi, Masahisa; Taniguchi, Yasuyo; Shibutani, Takayuki

2017-12-01

The aim of this study was to clarify the differences in thallium-201-chloride (thallium-201) myocardial perfusion imaging (MPI) scans evaluated by conventional anger-type single-photon emission computed tomography (conventional SPECT) versus cadmium-zinc-telluride SPECT (CZT SPECT) imaging in normal databases for different ethnic groups. MPI scans from 81 consecutive Japanese patients were examined using conventional SPECT and CZT SPECT and analyzed with the pre-installed quantitative perfusion SPECT (QPS) software. We compared the summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) for the two SPECT devices. For a normal MPI reference, we usually use Japanese databases for MPI created by the Japanese Society of Nuclear Medicine, which can be used with conventional SPECT but not with CZT SPECT. In this study, we used new Japanese normal databases constructed in our institution to compare conventional and CZT SPECT. Compared with conventional SPECT, CZT SPECT showed lower SSS (p < 0.001), SRS (p = 0.001), and SDS (p = 0.189) using the pre-installed SPECT database. In contrast, CZT SPECT showed no significant difference from conventional SPECT in QPS analysis using the normal databases from our institution. Myocardial perfusion analyses by CZT SPECT should be evaluated using normal databases based on the ethnic group being evaluated.

Computer interpretation of thallium SPECT studies based on neural network analysis

NASA Astrophysics Data System (ADS)

Wang, David C.; Karvelis, K. C.

1991-06-01

A class of artificial intelligence (Al) programs known as neural networks are well suited to pattern recognition. A neural network is trained rather than programmed to recognize patterns. This differs from "expert system" Al programs in that it is not following an extensive set of rules determined by the programmer, but rather bases its decision on a gestalt interpretation of the image. The "bullseye" images from cardiac stress thallium tests performed on 50 male patients, as well as several simulated images were used to train the network. The network was able to accurately classify all patients in the training set. The network was then tested against 50 unknown patients and was able to correctly categorize 77% of the areas of ischemia and 92% of the areas of infarction. While not yet matching the ability of a trained physician, the neural network shows great promise in this area and has potential application in other areas of medical imaging.

Advances in PET myocardial perfusion imaging: F-18 labeled tracers.

PubMed

Rischpler, Christoph; Park, Min-Jae; Fung, George S K; Javadi, Mehrbod; Tsui, Benjamin M W; Higuchi, Takahiro

2012-01-01

Coronary artery disease and its related cardiac disorders represent the most common cause of death in the USA and Western world. Despite advancements in treatment and accompanying improvements in outcome with current diagnostic and therapeutic modalities, it is the correct assignment of these diagnostic techniques and treatment options which are crucial. From a diagnostic standpoint, SPECT myocardial perfusion imaging (MPI) using traditional radiotracers like thallium-201 chloride, Tc-99m sestamibi or Tc-99m tetrofosmin is the most utilized imaging technique. However, PET MPI using N-13 ammonia, rubidium-82 chloride or O-15 water is increasing in availability and usage as a result of the growing number of medical centers with new-generation PET/CT systems taking advantage of the superior imaging properties of PET over SPECT. The routine clinical use of PET MPI is still limited, in part because of the short half-life of conventional PET MPI tracers. The disadvantages of these conventional PET tracers include expensive onsite production and inconvenient on-scanner tracer administration making them unsuitable for physical exercise stress imaging. Recently, two F-18 labeled radiotracers with longer radioactive half-lives than conventional PET imaging agents have been introduced. These are flurpiridaz F 18 (formerly known as F-18 BMS747158-02) and F-18 fluorobenzyltriphenylphosphonium. These longer half-life F-18 labeled perfusion tracers can overcome the production and protocol limitations of currently used radiotracers for PET MPI.

Myocardial viability assessment with dynamic low-dose iodine-123-iodophenylpentadecanoic acid metabolic imaging: comparison with myocardial biopsy and reinjection SPECT thallium after myocardial infarction.

PubMed

Murray, G L; Schad, N C; Magill, H L; Vander Zwaag, R

1994-04-01

Aggressive cardiac revascularization requires recognition of stunned and hibernating myocardium, and cost considerations may well govern the technique used. Dynamic low-dose (1 mCi) [123I]iodophenylpentadecanoic acid (IPPA) metabolic imaging is a potential alternative to PET using either 18FDG or 15O-water. Resting IPPA images were obtained from patients with severe ischemic cardiomyopathy, and transmural myocardial biopsies were obtained during coronary bypass surgery to confirm viability. Thirty-nine of 43 (91%) biopsies confirmed the results of the IPPA images with a sensitivity for viability of 33/36 (92%) and a specificity of 6/7 (86%). Postoperatively, wall motion improved in 80% of IPPA-viable, dysfunctional segments. Furthermore, when compared to reinjection thallium (SPECT-TI) scans after myocardial infarction, IPPA-SPECT-TI concordance occurred in 27/35 (77%) (K = 0.536, p = 0.0003). Similar to PET, IPPA demonstrated more viability than SPECT-TI, 26/35 (74%) versus 18/35 (51%) (p = 0.047). Metabolic IPPA cardiac viability imaging is a safe, inexpensive technique that may be a useful alternative to PET.

Effects of the repeated administration of adenosine and heparin on myocardial perfusion in patients with chronic stable angina pectoris.

PubMed

Barron, H V; Sciammarella, M G; Lenihan, K; Michaels, A D; Botvinick, E H

2000-01-01

The mechanism by which ischemia stimulates angiogenesis is unknown. Adenosine is released during myocardial ischemia and may be a mediator of this process. Experimental data suggest that heparin may enhance this effect. The purpose of this open-labeled, placebo-controlled trial was to determine whether repeated intravenous administration of adenosine and heparin could mimic physiologic angiogenesis and reduce the amount of exercise-induced myocardial ischemia in patients with coronary artery disease. Subjects with chronic stable angina refractory to conventional medical therapy and not suitable for revascularization received either adenosine (140 microg/kg/min for 6 minutes) and heparin (10,000 U bolus), (n = 14), or placebo, (n = 7) daily for 10 days. All patients underwent baseline and follow-up exercise testing with thallium-201 single-photon emission computed tomography myocardial perfusion imaging. A semiquantitative assessment of the extent and severity of the perfusion abnormalities was calculated by 2 blinded investigators. There was no significant change in exercise duration or in the peak heart rate systolic blood pressure product associated with adenosine and heparin compared with placebo treatment. There was, however, a 9% reduction in the extent (60.6 +/- 4.0 vs 54.9 +/- 4.1, p = 0.03) and a 14% improvement in severity (41.5 +/- 3.2 vs 35.7 +/- 2.9, p = 0.01) of the myocardial perfusion abnormalities seen in patients who received adenosine and heparin compared with placebo. Thus, in this pilot study, repeated administration of adenosine and heparin reduced the amount of exercise-induced ischemia in patients with chronic stable angina refractory to conventional treatment.

Study on the treatment of acute thallium poisoning.

PubMed

Zhang, Hong-Tao; Qiao, Bao-Ping; Liu, Bao-Ping; Zhao, Xian-Guo

2014-05-01

Acute thallium poisoning rarely occurs but is a serious and even fatal medical condition. Currently, patients with acute thallium poisoning are usually treated with Prussian blue and blood purification therapy. However, there are few studies about these treatments for acute thallium poisoning. Nine patients with acute thallium poisoning from 1 family were treated successfully with Prussian blue and different types of blood purification therapies and analyzed. Prussian blue combined with sequential hemodialysis, hemoperfusion and/or continuous veno-venous hemofiltration were effective for the treatment of patients with acute thallium poisoning, even after delayed diagnosis. Blood purification therapies help in the clearance of thallium in those with acute thallium poisoning. Prussian blue treatment may do the benefit during this process.

Cost-effectiveness of alternative test strategies for the diagnosis of coronary artery disease.

PubMed

Garber, A M; Solomon, N A

1999-05-04

The appropriate roles for several diagnostic tests for coronary disease are uncertain. To evaluate the cost-effectiveness of alternative approaches to diagnosis of coronary disease. Meta-analysis of the accuracy of alternative diagnostic tests plus decision analysis to assess the health outcomes and costs of alternative diagnostic strategies for patients at intermediate pretest risk for coronary disease. Studies of test accuracy that met inclusion criteria; published information on treatment effectiveness and disease prevalence. Men and women 45, 55, and 65 years of age with a 25% to 75% pretest risk for coronary disease. 30 years. Societal. Diagnostic strategies were initial angiography and initial testing with one of five noninvasive tests--exercise treadmill testing, planar thallium imaging, single-photon emission computed tomography (SPECT), stress echocardiography, and positron emission tomography (PET)--followed by coronary angiography if noninvasive test results were positive. Testing was followed by observation, medical treatment, or revascularization. Life-years, quality-adjusted life-years (QALYs), costs, and costs per QALY. Life expectancy varied little with the initial diagnostic test; for a 55-year-old man, the best-performing test increased life expectancy by 7 more days than the worst-performing test. More sensitive tests increased QALYs more. Echocardiography improved health outcomes and reduced costs relative to stress testing and planar thallium imaging. The incremental cost-effectiveness ratio was $75,000/QALY for SPECT relative to echocardiography and was greater than $640,000 for PET relative to SPECT. Compared with SPECT, immediate angiography had an incremental cost-effectiveness ratio of $94,000/QALY. Qualitative findings varied little with age, sex, pretest probability of disease, or the test indeterminancy rate. Results varied most with sensitivity to severe coronary disease. Echocardiography, SPECT, and immediate angiography are cost-effective alternatives to PET and other diagnostic approaches. Test selection should reflect local variation in test accuracy.

Optimization of a simultaneous dual-isotope 201Tl/123I-MIBG myocardial SPECT imaging protocol with a CZT camera for trigger zone assessment after myocardial infarction for routine clinical settings: Are delayed acquisition and scatter correction necessary?

PubMed

D'estanque, Emmanuel; Hedon, Christophe; Lattuca, Benoît; Bourdon, Aurélie; Benkiran, Meriem; Verd, Aurélie; Roubille, François; Mariano-Goulart, Denis

2017-08-01

Dual-isotope 201 Tl/ 123 I-MIBG SPECT can assess trigger zones (dysfunctions in the autonomic nervous system located in areas of viable myocardium) that are substrate for ventricular arrhythmias after STEMI. This study evaluated the necessity of delayed acquisition and scatter correction for dual-isotope 201 Tl/ 123 I-MIBG SPECT studies with a CZT camera to identify trigger zones after revascularization in patients with STEMI in routine clinical settings. Sixty-nine patients were prospectively enrolled after revascularization to undergo 201 Tl/ 123 I-MIBG SPECT using a CZT camera (Discovery NM 530c, GE). The first acquisition was a single thallium study (before MIBG administration); the second and the third were early and late dual-isotope studies. We compared the scatter-uncorrected and scatter-corrected (TEW method) thallium studies with the results of magnetic resonance imaging or transthoracic echography (reference standard) to diagnose myocardial necrosis. Summed rest scores (SRS) were significantly higher in the delayed MIBG studies than the early MIBG studies. SRS and necrosis surface were significantly higher in the delayed thallium studies with scatter correction than without scatter correction, leading to less trigger zone diagnosis for the scatter-corrected studies. Compared with the scatter-uncorrected studies, the late thallium scatter-corrected studies provided the best diagnostic values for myocardial necrosis assessment. Delayed acquisitions and scatter-corrected dual-isotope 201 Tl/ 123 I-MIBG SPECT acquisitions provide an improved evaluation of trigger zones in routine clinical settings after revascularization for STEMI.

Revision of gonadal radiation dose to man from thallium-201

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hosain, P.; Hosain, F.

1981-06-01

Thallium-201 as thallous chloride is now routinely used for myocardial imaging. We observed a biological translocation of T1-201 leading to a gradual increase in the concentration of radioactivity in the testes which facilitated testicular imaging. The initial distribution of intravenously injected tracer dose is greatly dependent on the distribution of cardiac output, but its metabolic fate is analogous to the potassium ion. We have extensively studied the kinetics of thallium in rats, and also carried out limited comparative studies in different species. An attempt was also made to compare the uptake values that could be obtained in dogs by quantitativemore » imaging and by autopsy. Separation of scrotum, epididymis and testes revealed that the increase in uptake occurred predominantly in the testes. The uptake increased with time for about 1 day, and after 2 days it declined with a biological half-life of approximately 2 days. The later phase of testicular clearance was similar to the rate of clearance from other organs. The testicular uptake of T1-201 was highest in rats: the initial value at 10 to 15 min was 0.48 +- 0.09% of the injected dose which increased to 1.77 +- 0.20% by 1 day. The initial uptake in mice was low (0.18 +- 0.06%) but it increased to about 4 folds by 1 day. Values in human, extrapolated from limited quantitative imaging, was similar to mice. These studies indicated the need for the revision of the gonadal radiation dose to man. Calculations show, contrary to the accepted value of about 0.5 rads/mCi, an approximate value of 1.5 rads/mCi is more realistic.« less

[Diagnosis of myocardial infarction by cine MR imaging--a comparative study with thallium-201 myocardial SPECT].

PubMed

Shiozaki, H

1993-01-25

The usefulness of cine magnetic resonance (MR) imaging was evaluated in 41 patients with acute (4 cases), subacute (21 cases) and chronic (16 cases) myocardial infarctions on the basis of the findings of thallium-201 myocardial SPECT. The overall rate of diagnostic accordance between cine MR imaging and SPECT was 85.0% (408/480). It was highest at the middle of the left ventricle (89.0%, 146/164) and lowest at the base (82.7%, 129/156). Measurement of wall thickness using the images printed on films was possible in 87.1% of segments (418/480). There was a significant difference in end-diastolic wall thickness and %-thickening between the infarcted and non-infarcted sites except for the base of the left ventricle. However, diastolic wall thinning was not remarkable in acute cases of less than one week after onset. In these cases %-thickening may be useful. Partial volume averaging on MR imaging and the inaccuracy of SPECT findings at the base also made meaningful comparison difficult. The most important diagnostic findings of myocardial infarction on cine MR imaging were end-diastolic wall thinning and abnormal motion such as akinesis and dyskinesis. It is concluded that cine MR imaging is a useful noninvasive examination method for evaluating the status of cardiac function in myocardial infarction.

Production of high purity radiothallium

DOEpatents

Lebowitz, Elliot; Greene, Margaret W.

1976-11-23

The method of producing high purity thallium-201 for use as a myocardial scanning agent comprising the steps of irradiating a thallium target with protons to give the reaction .sup.203 Tl(p,3n) .sup.201.sub.Pb, separating in ion exchange columns the lead from the thallium isotopes, permitting the lead to decay, and then purifying the thallium solution and converting the thallium present to thallous form in which it can be used.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanaka, T.; Kimata, S.; Hirosawa, K.

To determine whether thallium lung uptake images (TLI) can be used as a noninvasive method to estimate any of hemodynamic changes in patients (pts) with acute myocardial infarction (AMI) TLI were evaluated in 23 pts with AMI. All pts underwent multigated blood pool imaging and cardiac catheterization. TLI were estimated by comparing the intensity of T1-201 activity in the lower right lung with maximal myocardial count (thallium lung heart ratio; LHR). Pts with AMI were classified to 3 grades according to LHR. The classifications were hemodynamically significant. The specificity of LHR <0.6 for mPw <18mmHg was 100% (10/10). The specificitymore » of LHR greater than or equal to 0.8 for mPw greater than or equal to 18mmHg was 85% (11/13) and for EF greater than or equal to 30% was 100% (13/13). The pts with LHR 0.8 showed high mortality (4/9) and high morbidity (all survivors were in NYHA class 2-3 and receiving digitalis and diuretics). TLI were easily obtained after routine T1-myocardial imaging, i.e. another 5 minutes imaging yielded clinically useful information for separating high and low-risk groups of pts with AMI.« less

Method for the preparation of thallium-containing superconducting materials by precipitation

DOEpatents

Bunker, Bruce C.; Lamppa, Diana L.; Voigt, James A.

1991-01-01

This invention provides improved methods for the preparation of precursor powders that are used in the preparation of superconducting ceramic materials that contain thallium. A first solution that contains the hydrogen peroxide and metal cations, other than thallium, that will be part of the ceramic is quickly mixed with a second solution that contains precipitating anions and thallium (I) to form a precipitate which is dried to yield precursor powders. The precursor powders are calcined an sintered to produce superconducting materials that contain thallium.

Search for extinct natural radioactivity of Pb205 via thallium-isotope anomalies in chondrites and lunar soil.

NASA Technical Reports Server (NTRS)

Huey, J. M.; Kohman, T. P.

1972-01-01

Thallium and Pb204 contents were determined by stable-isotope-dilution analysis in 16 chondrites, one achondrite, and Apollo 11 and 12 lunar fines. Meteoritic thallium contents vary over a large range, 0.02 to 100 ppb, corresponding to the fact that thallium is a highly fractionated volatile element. Lunar thallium contents are less than 5 ppb. The Tl205/Tl203 ratio was determined in most of the samples, with precision ranging from 0.03% to several percent depending mainly on the amount of thallium present. No variations from the terrestrial ratio were observed. The chondritic isochron slope for Pb205 (13.8-m.y. half-life) is less than or equal to 0.00009 (99% confidence level), corresponding to an interval of at least 60 m.y. and possibly exceeding 120 m.y. between the termination of s-process nucleosynthesis and the lead-thallium fractionations.

Chelation of Thallium (III) in Rats Using Combined Deferasirox and Deferiprone Therapy.

PubMed

Salehi, Samie; Saljooghi, Amir Sh; Badiee, Somayeh; Moqadam, Mojtaba Mashmool

2017-10-01

Thallium and its compounds are a class of highly toxic chemicals that cause wide-ranging symptoms such as gastrointestinal disturbances; polyneuritis; encephalopathy; tachycardia; skin eruptions; hepatic, renal, cardiac, and neurological toxicities; and have mutagenic and genotoxic effects. The present research aimed to evaluate the efficacy of the chelating agents deferasirox (DFX) and deferiprone (L1) in reducing serum and tissue thallium levels after the administration of thallium (III), according to two different dosing regimens, to several groups of Wistar rats for 60 days. It was hypothesized that the two chelators might be more efficient as a combined therapy than as monotherapies in removing thallium (III) from the rats' organs. The chelators were administered orally as either single or combined therapies for a period of 14 days. Serum and tissue thallium (III) and iron concentrations were determined by flame atomic absorption spectroscopy. Serum and tissue thallium (III) levels were significantly reduced by combined therapy with DFX and L1. Additionally, iron concentrations returned to normal levels and symptoms of toxicity decreased.

Thallium-induced testicular toxicity in the rat.

PubMed

Formigli, L; Scelsi, R; Poggi, P; Gregotti, C; Di Nucci, A; Sabbioni, E; Gottardi, L; Manzo, L

1986-08-01

Reproductive tract functions were studied in adult male Wistar rats given 10 ppm thallium as thallium sulfate in the drinking water. After 60 days of treatment, spermatozoa isolated from the cauda epididymides and vas deferens showed reduced motility and immature germ cells were found in the tubular lumen. Histological examination of testes in thallium-treated animals revealed disarrangement of the tubular epithelium and ultrastructural changes in the Sertoli cells with cytoplasmic vacuolation and distension of the smooth endoplasmic reticulum. The activity of testicular beta-glucuronidase was significantly reduced whereas acid phosphatase and sorbitol dehydrogenase activities were unchanged. Plasma testosterone levels were within normal limits. No abnormalities in testicular morphology and biochemistry were seen in animals sacrificed at the end of the first month of thallium exposure. These findings indicate that the male reproductive system is a susceptible target site to toxic effects of thallium under chronic exposure. They also suggest a major involvement of Sertoli cells in the mechanism underlying thallium-induced testicular damage.

AIDS-related Kaposi sarcoma: findings on thallium-201 scintigraphy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, V.W.; Rosen, M.P.; Baum, A.

1988-12-01

No simple, noninvasive method is available for evaluating extracutaneous Kaposi sarcoma in AIDS patients or for following the tumor's response to treatment. We report our preliminary experience with thallium-201 scintigraphy in nine AIDS patients with proved Kaposi sarcoma. Eight of the nine had abnormal uptake of the radionuclide in skin, lymph nodes, oral cavity, vagina, and lungs. Only four of the nine had cutaneous Kaposi sarcoma at the time of scanning. All cutaneous and mucosal lesions were thallium avid. Two of the six patients with thallium-avid nodes underwent nodal biopsy. Both biopsies confirmed the diagnosis of Kaposi sarcoma. Cutaneous Kaposimore » sarcoma developed later in one of these patients, showing the efficacy of thallium scintigraphy for the early detection of extracutaneous lesions. These preliminary results show thallium avidity in Kaposi sarcoma involving the skin and various extracutaneous sites (lymph nodes, lung, mucosa, and vagina). Thallium scintigraphy is a potentially useful procedure for detecting extracutaneous Kaposi sarcoma in AIDS patients.« less

Method of fabricating a (1223) Tl-Ba-Ca-Cu-O superconductor

DOEpatents

Tkaczyk, John Eric; Lay, Kenneth Wilbur; He, Qing

1997-01-01

A method is disclosed for fabricating a polycrystalline <223> thallium-containing superconductor having high critical current at elevated temperatures and in the presence of a magnetic field. A powder precursor containing compounds other than thallium is compressed on a substrate. Thallium is incorporated in the densified powder precursor at a high temperature in the presence of a partial pressure of a thallium-containing vapor.

Nuclear cardiology: Part 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berger, H.J.; Zaret, B.L.

1981-10-01

A review of recent developments and future directions in nuclear cardiology is presented. Myocardial perfusion imaging is discussed with special emphasis on thallium-201 methods. Infarct-avid imaging is also discussed with emphasis on technetium-99m labelled in diagnosis, and emission computed tomography is briefly reviewed. In addition, new biologically based radiotracers such as indium-111-labeled blood cells, gallium-67 citrate, and new positron- and gamma-emittng radiotracers are reviewed.

Method of fabricating a (1223) Tl-Ba-Ca-Cu-O superconductor

DOEpatents

Tkaczyk, J.E.; Lay, K.W.; He, Q.

1997-07-08

A method is disclosed for fabricating a polycrystalline <223> thallium-containing superconductor having high critical current at elevated temperatures and in the presence of a magnetic field. A powder precursor containing compounds other than thallium is compressed on a substrate. Thallium is incorporated in the densified powder precursor at a high temperature in the presence of a partial pressure of a thallium-containing vapor. 2 figs.

[Solitary actinomycotic brain abscess: case report].

PubMed

Takahashi, Kiyoshi; Hasegawa, Yoshihito; Nishimoto, Yo; Hayashi, Satoru; Yamasaki, Masahiro; Kuzume, Daisuke; Hashimoto, Keiko; Enzan, Hideaki

2012-06-01

Actinomycotic brain abscess is a rare condition with uncertain clinical features. Here we report the case of a 66-year-old immune-competent woman with an actinomycotic brain abscess who presented with sensory aphasia and mild right hemiparesis. She had no febrile episode or headache. Moreover, she did not have any periodontal or oto-rhino-laryngological disease, and the results of laboratory tests were normal. A computed tomography scan showed an irregular, low-density area in the left parietal lobe. Subsequent magnetic resonance imaging showed low-signal intensity in a T1 weighted image, high-signal intensity in a T2 weighted image, and mixed intensity on a diffusion weighted image. Thallium-201 chloride scintigraphy showed definite accumulation of thallium in the lesion and the patient's condition gradually deteriorated. Ten days after gadolinium administration, a T1 weighted image showed a multi- lobulated irregular mass in the left parietal lobe. The patient subsequently underwent craniotomy and evacuation of the yellowish abscess. Gram staining of the tissue showed the presence of gram-positive filamentous rods, and abscess cultures were positive for Actinomyces and Prevotella disiens. The abscess resolved after treatment with a high dose of intravenous penicillin G (24 million units/day) for 8 weeks, followed by an oral dose of amoxicillin for 4 months. The patient was discharged with a rudimentary limitation of the visual field.

In vivo effects of radioactive properties of Tl-201 on human carbonic anhydrase activity

NASA Astrophysics Data System (ADS)

Sahin, Ali; Senturk, Murat

2017-04-01

Carbonic anhydrase (CA) is a family of metalloenzymes that requires Zn as a cofactor and catalyze the quick conversion of CO2 to HCO3- and H+. Inhibitors of the carbonic anhydrases (CAs) have medical usage of significant diseases such as glaucoma, epilepsy, gastroduodenal ulcers, acid-base disequilibria and neurological disorders. The most useful radioisotope, Tl-201, decays by electron capture, emitting Hg X-rays ( 70-80 keV), and photons of 135 and 167 keV in 10% total abundance. Therefore, it has good imaging characteristics without excessive patient radiation dose. It is the most popular isotope used for thallium 201 nuclear cardiac stress tests. In the present study, In vivo inhibitory effect of Tl-201 (Thallium-201) on human erythrocyte carbonic anhydrase (CA) activity were investigated.

Thallium Bromide Deposited Using Spray Coating

NASA Astrophysics Data System (ADS)

Ferreira, E. S.; Mulato, M.

2012-08-01

Spray coating was used to produce thallium bromide samples on glass substrates. The influence of several fabrication parameters on the final structural properties of the samples was investigated. Substrate position, substrate temperature, solution concentration, carrying gas, and solution flow were varied systematically, the physical deposition mechanism involved in each case being discussed. Total deposition time of about 3.5 h can lead to 62-μm-thick films, comprising completely packed micrometer-sized crystalline grains. X-ray diffraction and scanning electron microscopy were used to characterize the samples. On the basis of the experimental data, the optimum fabrication conditions were identified. The technique offers an alternative method for fast, cheap fabrication of large-area devices for the detection of high-energy radiation, i.e., X-rays and γ-rays, in medical imaging.

Radionuclide imaging in myocardial sarcoidosis. Demonstration of myocardial uptake of /sup 99m/Tc pyrophosphate and gallium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forman, M.B.; Sandler, M.P.; Sacks, G.A.

1983-03-01

A patient had severe congestive cardiomyopathy secondary to myocardial sarcoidosis. The clinical diagnosis was confirmed by radionuclide ventriculography, /sup 201/Tl, /sup 67/Ga, and /sup 99m/Tc pyrophosphate (TcPYP) scintigraphy. Myocardial TcPYP uptake has not been reported previously in sarcoidosis. In this patient, TcPYP was as useful as gallium scanning and thallium imaging in documenting the myocardial process.

[Disorder of porphyrin metabolism in thallium intoxication (author's transl)].

PubMed

Graben, N; Doss, M; Klöppel, H A

1978-08-04

A 19-year old male ingested in suicidal attempt 750 mg of thallium. He developed the characteristic symptoms of thallium intoxication. During the acute phase the urinary excretion of porphyrins and porphyrin precursors was largely increased. The percentage distribution of the individual metabolites of heme synthesis revealed a preponderance of kopro- and uroporphyrin. This constellation (kopro- greater than uro- greater than tricarboxylic porphyrin) differs appreciably from that one in lead intoxication. The observation of increased urinary excretion of porphyrins and their precursors in a possibly particular spectrum in thallium intoxication is of special interest for differential-diagnostic reasoning. In each case of a toxic disorder of porphyrin metabolism thallium intoxication ought to be considered a possible cause.

Cardiac nuclear medicine, part II: diagnosis of coronary artery diseas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polak, J.F.; Holman, B.L.

Diagnosing coronary artery disease is difficult and requires careful consideration of the roles and limitations of the tests used. Standard ECG tests are not reliable indicators of the presence of disease in asymptomatic patients. Thallium stress testing to assess ischemia and exercise ventriculography to assess functional status of the heart are limited in sensitivity and specificity. This is the second of a three-part series on cardiac nuclear medicine. Part I (Med. Instrum., May-June, 1981) focused on the commonly used examinations in cardiac physiology and pathophysiology. Part III will focus on myocardial infarction and other cardiac diseases.

Myocardial scintigraphy with 201thallium in pediatric cardiology: A review of 52 cases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bjoerkhem, G.E.; Evander, E.; White, T.

1990-01-01

We report our experience of myocardial scintigraphy with 201thallium (201Tl) in 52 children, aged 4 days to 18 years, in which 80 studies were made primarily to demonstrate or exclude impaired myocardial perfusion. For analysis, the patients were divided into the following eight groups: group I, coronary artery malformations (five patients); group II, Kawasaki's syndrome (six patients); group III, arterial switch operation (seven patients); group IV, dilated cardiomyopathy (18 patients); group V, hypertrophic cardiomyopathy (four patients); group VI, myocardial dysfunction after surgery for congenital heart disease (five patients); group VII, pulmonary atresia (three patients); and group VIII, miscellaneous (four patients).more » Myocardial scintigraphy was performed with a planar or tomographic technique at rest or after exercise (four patients). Isotope-uptake defects, indicating impaired myocardial perfusion, were present in 14 patients, including small infants. Defects were seen in all groups except those with hypertrophic cardiomyopathy and pulmonary atresia. The absence of such defects in several of the patients with Kawasaki's syndrome was particularly valuable as it made coronary angiography unnecessary. In the other groups of patients myocardial scintigraphy was a valuable adjunct to other investigations.« less

Qualitative evaluation of coronary flow during anesthetic induction using thallium-201 perfusion scans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kleinman, B.; Henkin, R.E.; Glisson, S.N.

Qualitative distribution of coronary flow using thallium-201 perfusion scans immediately postintubation was studied in 22 patients scheduled for elective coronary artery bypass surgery. Ten patients received a thiopental (4 mg/kg) and halothane induction. Twelve patients received a fentanyl (100 micrograms/kg) induction. Baseline thallium-201 perfusion scans were performed 24 h prior to surgery. These scans were compared with the scans performed postintubation. A thallium-positive scan was accepted as evidence of relative hypoperfusion. Baseline hemodynamic and ECG data were obtained prior to induction of anesthesia. These data were compared with the data obtained postintubation. Ten patients developed postintubation thallium-perfusion scan defects (thallium-positivemore » scan), even though there was no statistical difference between their baseline hemodynamics and hemodynamics at the time of intubation. There was no difference in the incidence of thallium-positive scans between those patients anesthetized by fentanyl and those patients anesthetized with thiopental-halothane. The authors conclude that relative hypoperfusion, and possibly ischemia, occurred in 45% of patients studied, despite stable hemodynamics, and that the incidence of these events was the same with two different anesthetic techniques.« less

Is there any advantage to the acquisition of 24-hour thallium images, in the presence of persistent perfusion defects at 4 h after reinjection?

PubMed

Bobba, K; Botvinick, E H; Sciammarella, M G; Starsken, N F; Zhu, Y Y; Lapidus, A; Dae, M W

1998-05-01

We determined the incidence of delayed 24-h reversibility post thallium-201 reinjection and imaging at 4 h, as well as the prognostic and significance of such delayed reversibility. We studied 46 consecutive patients with persistent thallium-201 perfusion or incompletely reversible single-photon emission tomography (SPET) perfusion defects acquired within 10 min after reinjection performed 4 h after stress. In 38 of 46 patients (82%) 24-h images showed no further reversibility beyond the post-reinjection 4-h study (group A). Eight of 46 patients (17%) demonstrated reversibility on 24-h imaging (group B). Of these eight, three patients showed no improvement compared with the post-stress images, with a mean perfusion score of the abnormal segments of 1. 25+/-0.50 on the 4-h images, and of 3.00 on the 24-h images, where normal is 4. Four patients presented with nine mixed regions. Four of these regions showed an improvement in the mean perfusion score of 2.50+/-0.58 on 4- and 24-h images. Two of them, with moderate/severe defects, demonstrated complete reversibility at 4-h post-reinjection imaging. In addition, five other regions presented no improvement at 4-h imaging, but showed an improvement in the mean perfusion score from 0.80+/-0.84 at 4-h to 3.30+/-0.89 at 24-h imaging. Two of these regions in one patient showed a severe perfusion score of 0 at 4 h, and complete reversibility at 24 hours, with a mean score improvement of 4. Another patient had three severe perfusion defects; two of them redistributed partially at 4 h and completely at 24 h. The remaining segment with a perfusion score of 0 at 4 h, presented complete reversibility with a score of 4 at 24 h. Two (4%) patients revealed significant reversibility at 24 h in a region that was severely underperfused after post-reinjection imaging at 4 h. Among group B patients, 75% (6/8) had recent acute ischemic syndrome, compared with only 13% (5/38) in group A (P = 0. 001). Among 11 patients with unstable angina, six (55%) had evidence of delayed 24-h reversibility, compared with 2 of 35 (6%) patients without clinically acute ischemia (P = 0.001). On follow-up, there were seven (17%) cardiac deaths among the 38 group A patients but three (38%) among the eight group B patients (P = 0.3). These findings suggest that although the presence of delayed 24-h 201Tl, post-reinjection reversibility is infrequent, it has potential clinical importance. Thus, delayed 24-h imaging should be considered in the context of unstable angina or other acute coronary syndromes.

Neuropsychology of thallium poisoning

PubMed Central

McMillan, T; Jacobson, R; Gross, M

1997-01-01

Cases of thallium poisoning are rare and neuropsychological assessment has only been reported in detail in one other case. In the case reported here, neuropsychological assessments were carried out three, 12, and 54 months after diagnosis of thallium poisoning in a man who had acutely shown a number of neurological signs including confusion and disorientation and generalised slowing of EEG which was more prominent on the left. Evidence suggested that he had been exposed to thallium over a period of weeks. Neuropsychological assessment indicated an unexpected weakness in verbal abilities which persisted. This finding is consistent with the only other published case report which details neuropsychological effects after a single large dose of thallium and which also found a lateralised impairment.

 PMID:9285467

Assessment of residual tissue viability by exercise testing in recent myocardial infarction: comparison of the electrocardiogram and myocardial perfusion scintigraphy.

PubMed

Margonato, A; Ballarotto, C; Bonetti, F; Cappelletti, A; Sciammarella, M; Cianflone, D; Chierchia, S L

1992-04-01

The assessment of residual myocardial viability in infarcted areas is relevant for subsequent management and prognosis but requires expensive technology. To evaluate the possibility that simple, easily obtainable clinical markers may detect the presence of within-infarct viable tissue, the significance of exercise-induced ST elevation occurring in leads exploring the area of a recent Q wave myocardial infarction was assessed. Twenty-five patients with recent (less than 6 months) myocardial infarction were studied. All had angiographically documented coronary artery disease, diagnostic Q waves (n = 24) or negative T waves (n = 25) on the rest 12-lead electrocardiogram and exhibited during exercise greater than or equal to 1.5 mm ST segment elevation (n = 17) or isolated T wave pseudonormalization (n = 8) in the infarct-related leads. ST-T wave changes were reproduced in all patients during thallium-201 exercise myocardial scintigraphy. A fixed perfusion defect was observed in 24 of the 25 patients. A reversible defect was seen in 16 (94%) of 17 patients who exhibited transient ST elevation during exercise but in only 4 (50%) of the 8 patients who had only T wave pseudonormalization. In conclusion, in patients with recent myocardial infarction, analysis of simple ST segment variables obtained during exercise testing may allow a first-line discrimination of those who may potentially benefit from a revascularization procedure.

[Characterization of kale (Brassica oberacea var acephala) under thallium stress by in situ attenuated total reflection FTIR].

PubMed

Yao, Yan; Zhang, Ping; Wang, Zhen-Chun; Chen, Yong-Heng

2009-01-01

The experiment was designed based on consumption of carbon dioxide through the photosynthesis of Brassica oberacea var acephala leaf, and the photosynthesis of kale leaf under thallium stress was investigated by in situ attenuated total reflection FTIR (in situ ATR-FTIR). The ATR-FTIR showed that the absorption peaks of leaves had no obvious difference between plants growing in thallium stress soil and plants growing in non-thallium pollution soil, and the strong peaks at 3,380 cm(-1) could be assigned to the absorption of water, carbohydrate, protein or amide; the strong peaks at 2,916 and 2,850 cm(-1) assigned to the absorption of carbohydrate or aliphatic compound; the peaks at 1,640 cm(-1) assigned to the absorption of water. However, as detected by the in situ ATR-FTIR, the double peaks (negative peaks) at 2,360 and 2,340 cm(-1) that are assigned to the absorption of CO2 appeared and became high gradually. It was showed that kale was carrying photosynthesis. At the same time, the carbon dioxide consumption speed of leaf under thallium stress was obviously larger than that of the blank It was expressed that photosynthesis under thallium stress was stronger than the blank All these represented that kale had certain tolerance to the heavy metal thallium. Meanwhile, the carbon dioxide consumption of grown-up leaf was more than that of young leaf whether or not under thallium stress. It was also indicated that the intensity of photosynthesis in grown-up leaf is higher than that in young leaf.

Reversion of left ventricular systolic dysfunction and abnormal stress test: by catheter ablation, in a patient with Wolff-Parkinson-White syndrome from Para-Hisian Kent bundle.

PubMed

Tu, Chung-Ming; Chu, Kai-Ming; Cheng, Cheng-Chung; Cheng, Shu-Mung; Lin, Wei-Shiang

2010-01-01

The diagnosis of Wolff-Parkinson-White syndrome is typically reserved for patients who experience ventricular pre-excitation and symptoms that are related to paroxysmal supraventricular tachycardia, such as chest pain, dyspnea, dizziness, palpitations, or syncope. Herein, we report the case of a 38-year-old woman who presented at our outpatient department because of exercise intolerance. Cardiac auscultation revealed a grade 2/6 pansystolic murmur over the left lower sternal border. Twelve-lead electrocardiography showed sinus rhythm at a rate of 76 beats/min, with a significant delta wave. Transthoracic echocardiography revealed abnormal left ventricular systolic function. The results of a thallium stress test were also abnormal. Coronary artery disease was suspected; however, coronary angiography yielded normal results. Electrophysiologic study revealed a para-Hisian Kent bundle and a dual atrioventricular nodal pathway. After radiofrequency catheter ablation was performed, the patient's left ventricular function improved and her symptoms disappeared. In Wolff-Parkinson-White syndrome, left ventricular systolic dyssynchrony can yield abnormal findings on echocardiography and thallium scanning--even in persons who have no cardiovascular risk factors. Physicians who are armed with this knowledge can avoid performing coronary angiography unnecessarily. Catheter ablation can reverse the dyssynchrony of the ventricle and improve the patient's symptoms.

Separation of bismuth from gram amounts of thallium and silver by cation-exchange chromatography in nitric acid.

PubMed

Meintjies, E; Strelow, F W; Victor, A H

1987-04-01

Traces and small amounts of bismuth can be separated from gram amounts of thallium and silver by successively eluting these elements with 0.3M and 0.6M nitric acid from a column containing 13 ml (3 g) of AG50W-X4, a cation-exchanger (100-200 mesh particle size) with low cross-linking. Bismuth is retained and can be eluted with 0.2M hydrobromic acid containing 20% v/v acetone, leaving many other trace elements absorbed. Elution of thallium is quite sharp, but silver shows a small amount of tailing (less than 1 gmg/ml silver in the eluate) when gram amounts are present, between 20 and 80 mug of silver appearing in the bismuth fraction. Relevant elution curves and results for the analysis of synthetic mixtures containing between 50 mug and 10 mg of bismuth and up to more than 1 g of thallium and silver are presented, as well as results for bismuth in a sample of thallium metal and in Merck thallium(I) carbonate. As little as 0.01 ppm of bismuth can be determined when the separation is combined with electrothermal atomic-absorption spectrometry.

Scintigraphic calf perfusion symmetry after exercise and prediction of cardiovascular events: One stone to kill two birds?

NASA Astrophysics Data System (ADS)

Tellier, Philippe; Lecouffe, Pascal; Zureik, Mahmoud

2007-02-01

BackgroundPeripheral arterial disease (PAD) is commonly associated with a high cardiovascular mortality and morbidity as a marker of plurifocal atherosclerosis. Whether exercise thallium perfusion muscular asymmetry in the legs associated with PAD has prognostic value is unknown. Such a hypothesis was evaluated in a prospective study which remains the gold standard in clinical research. Methods and resultsScintigraphic calf perfusion symmetry after exercise (SCPSE) was measured at the end of a maximal or symptom-limited treadmill exercise test in 358 patients with known or suspected coronary artery disease (CAD). During the follow-up period (mean 85.3±32.8 months), 93 cardiovascular events and deaths (incident cases) occurred. Among those incident cases, the percentage of subjects with higher SCPSE values (third tertile) was 45.2%, versus 29.1% in controls (lower tertiles) ( p=0.005). In stepwise multivariate analysis performed with the Cox proportional hazards model, previous CAD and SCPSE were the only significant independent predictors of prognosis. The multivariate relative risk of cardiovascular death or event in subjects with higher values of SCPSE was 1.94 (95% CI: 1.15-3.21; p<0.01). ConclusionsScintigraphic calf perfusion asymmetry after exercise was independently associated with incident cardiovascular events in high-risk subjects. This index, which is easily and quickly calculated, could be used for evaluation of cardiovascular risk.

Stabilized thallium bromide radiation detectors and methods of making the same

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leao, Cedric Rocha; Lordi, Vincenzo

According to one embodiment, a crystal includes thallium bromide (TlBr), one or more positively charged dopants, and one or more negatively charged dopants. According to another embodiment, a system includes a monolithic crystal including thallium bromide (TlBr), one or more positively charged dopants, and one or more negatively charged dopants; and a detector configured to detect a signal response of the crystal.

Simultaneous Removal of Thallium and EDTA by Fenton Process

NASA Astrophysics Data System (ADS)

Xu, Ruibing; Huang, Xuexia; Li, Huosheng; Su, Minhua; Chen, Diyun

2018-01-01

The wastewater containing heavy metals and organic pollutants is widely discharged from industries. Because of the coexistence of heavy metals and organic pollutants, the treatment of such wastewater is very difficult. Fenton process is considered to be one of the most effective approaches for the degradation of organic pollutants in aqueous solution due to the strong oxidative ability of hydroxyl radical which generated from the Fenton process. Apart from this, heavy metals are able to be removed during Fenton process owning to the synergic effect of coagulation and precipitation. In this work, pollutants of thallium and EDTA were successfully removed via the Fenton process. A series of single-factor experiments were designed and performed to achieve an optimal reaction conditions for the removal of both thallium and EDTA. Results showed that the removal efficiencies of thallium and TOC could be as high as 96.54% and 70.42%, respectively. The outcomes from our study demonstrate that Fenton process is a promising method for the purification of wastewater containing thallium and EDTA.

Infrared attenuation of thallium bromo-iodide fibers

NASA Technical Reports Server (NTRS)

Magilavy, B.; Goebel, J.

1986-01-01

Analysis of attenuation measurements in the near infrared of an unclad fiber of Thallium Bromo-Iodide (Th(Br,I)), a polycrystalline thallium halide, is presented. A general overview is given of the properties of fiber optics. Two groups of attenuation measurements, for the region 1.2 to 3.4 and for 3 to 11 microns, respectively, are presented, analyzed, and compared with those of two other groups of researchers.

In-situ pre-concentration through repeated sampling and pyrolysis for ultrasensitive determination of thallium in drinking water by electrothermal atomic absorption spectrometry.

PubMed

Liu, Liwei; Zheng, Huaili; Xu, Bincheng; Xiao, Lang; Chigan, Yong; Zhangluo, Yilan

2018-03-01

In this paper, a procedure for in-situ pre-concentration in graphite furnace by repeated sampling and pyrolysis is proposed for the determination of ultra-trace thallium in drinking water by graphite furnace atomic absorption spectrometry (GF-AAS). Without any other laborious enrichment processes that routinely result in analyte loss and contamination, thallium was directly concentrated in the graphite furnace automatically and subsequently subject to analysis. The effects of several key factors, such as the temperature for pyrolysis and atomization, the chemical modifier, and the repeated sampling times were investigated. Under the optimized conditions, a limit of detection of 0.01µgL -1 was obtained, which fulfilled thallium determination in drinking water by GB 5749-2006 regulated by China. Successful analysis of thallium in certified water samples and drinking water samples was demonstrated, with analytical results in good agreement with the certified values and those by inductively coupled plasma mass spectrometry (ICP-MS), respectively. Routine spike-recovery tests with randomly selected drinking water samples showed satisfactory results of 80-96%. The proposed method is simple and sensitive for screening of ultra-trace thallium in drinking water samples. Copyright © 2017. Published by Elsevier B.V.

Ratiometric Phosphorescent Probe for Thallium in Serum, Water, and Soil Samples Based on Long-Lived, Spectrally Resolved, Mn-Doped ZnSe Quantum Dots and Carbon Dots.

PubMed

Lu, Xiaomei; Zhang, Jinyi; Xie, Ya-Ni; Zhang, Xinfeng; Jiang, Xiaoming; Hou, Xiandeng; Wu, Peng

2018-02-20

Thallium (Tl) is an extremely toxic heavy metal and exists in very low concentrations in the environment, but its sensing is largely underexplored as compared to its neighboring elements in the periodic table (especially mercury and lead). In this work, we developed a ratiometric phosphorescent nanoprobe for thallium detection based on Mn-doped ZnSe quantum dots (QDs) and water-soluble carbon dots (C-dots). Upon excitation with 360 nm, Mn-doped ZnSe QDs and C-dots can emit long-lived and spectrally resolved phosphorescence at 580 and 440 nm, respectively. In the presence of thallium, the phosphorescence emission from Mn-doped ZnSe QDs could be selectively quenched, while that from C-dots retained unchanged. Therefore, a ratiometric phosphorescent probe was thus developed, which can eliminate the potential influence from both background fluorescence and other analyte-independent external environment factors. Several other heavy metal ions caused interferences to thallium detection but could be efficiently masked with EDTA. The proposed method offered a detection limit of 1 μg/L, which is among the most sensitive probes ever reported. Successful application of this method for thallium detection in biological serum as well as in environmental water and soil samples was demonstrated.

Development of Scintillators in Nuclear Medicine.

PubMed

Khoshakhlagh, Mohammad; Islamian, Jalil Pirayesh; Abedi, Seyed Mohammad; Mahmoudian, Babak

2015-01-01

High-quality image is necessary for accurate diagnosis in nuclear medicine. There are many factors in creating a good image and detector is the most important one. In recent years, several detectors are studied to get a better picture. The aim of this paper is comparison of some type of these detectors such as thallium activated sodium iodide bismuth germinate cesium activated yttrium aluminum garnet (YAG: Ce) YAP: Ce "lutetium aluminum garnet activated by cerium" CRY018 "CRY019" lanthanum bromide and cadmium zinc telluride. We studied different properties of these crystals including density, energy resolution and decay times that are more important factors affecting the image quality.

Development of Scintillators in Nuclear Medicine

PubMed Central

Khoshakhlagh, Mohammad; Islamian, Jalil Pirayesh; Abedi, Seyed Mohammad; Mahmoudian, Babak

2015-01-01

High-quality image is necessary for accurate diagnosis in nuclear medicine. There are many factors in creating a good image and detector is the most important one. In recent years, several detectors are studied to get a better picture. The aim of this paper is comparison of some type of these detectors such as thallium activated sodium iodide bismuth germinate cesium activated yttrium aluminum garnet (YAG: Ce) YAP: Ce “lutetium aluminum garnet activated by cerium” CRY018 “CRY019” lanthanum bromide and cadmium zinc telluride. We studied different properties of these crystals including density, energy resolution and decay times that are more important factors affecting the image quality. PMID:26420984

Area at risk can be assessed by iodine-123-meta-iodobenzylguanidine single-photon emission computed tomography after myocardial infarction: a prospective study.

PubMed

Hedon, Christophe; Huet, Fabien; Ben Bouallegue, Fayçal; Vernhet, Hélène; Macia, Jean-Christophe; Cung, Thien-Tri; Leclercq, Florence; Cade, Stéphane; Cransac, Frédéric; Lattuca, Benoit; Vandenberghe, D'Arcy; Bourdon, Aurélie; Benkiran, Meriem; Vauchot, Fabien; Gervasoni, Richard; D'estanque, Emmanuel; Mariano-Goulart, Denis; Roubille, François

2018-02-01

Myocardial salvage is an important surrogate endpoint to estimate the impact of treatments in patients with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to evaluate the correlation between cardiac sympathetic denervation area assessed by single-photon emission computed tomography (SPECT) using iodine-123-meta-iodobenzylguanidine (I-MIBG) and myocardial area at risk (AAR) assessed by cardiac magnetic resonance (CMR) (gold standard). A total of 35 postprimary reperfusion STEMI patients were enrolled prospectively to undergo SPECT using I-MIBG (evaluates cardiac sympathetic denervation) and thallium-201 (evaluates myocardial necrosis), and to undergo CMR imaging using T2-weighted spin-echo turbo inversion recovery for AAR and postgadolinium T1-weighted phase sensitive inversion recovery for scar assessment. I-MIBG imaging showed a wider denervated area (51.1±16.0% of left ventricular area) in comparison with the necrosis area on thallium-201 imaging (16.1±14.4% of left ventricular area, P<0.0001). CMR and SPECT provided similar evaluation of the transmural necrosis (P=0.10) with a good correlation (R=0.86, P<0.0001). AAR on CMR was not different compared with the denervated area (P=0.23) and was adequately correlated (R=0.56, P=0.0002). Myocardial salvage evaluated by SPECT imaging (mismatch denervated but viable myocardium) was significantly higher than by CMR (P=0.02). In patients with STEMI, I-MIBG SPECT, assessing cardiac sympathetic denervation may precisely evaluate the AAR, providing an alternative to CMR for AAR assessment.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kahan, A.; Devaux, J.Y.; Amor, B.

In systemic sclerosis, abnormalities of myocardial perfusion are common and may be caused by a disturbance of the coronary microcirculation. We evaluated the long-term effect of captopril (75 to 150 mg per day) on thallium 201 myocardial perfusion in 12 normotensive patients with systemic sclerosis. Captopril significantly decreased the mean (+/- SD) number of segments with thallium 201 myocardial perfusion defects (6.5 +/- 1.9 at baseline and 4.4 +/- 2.7 after 1 year of treatment with captopril; p less than 0.02) and increased the mean global thallium score (9.6 +/- 1.7 at baseline and 11.4 +/- 2.1 after captopril; pmore » less than 0.05). In a control group of eight normotensive patients with systemic sclerosis who did not receive captopril, no significant modification in thallium results occurred. Side effects with captopril included hypotension (six patients), taste disturbances (one patient), and skin rash (one patient). These side effects subsided when the dosage was reduced. These findings demonstrate that captopril improves thallium 201 myocardial perfusion in patients with systemic sclerosis and may therefore have a beneficial effect on scleroderma myocardial disease.« less

Design of Multifunctional Materials: Chalcogenides and Chalcopyrites

NASA Technical Reports Server (NTRS)

Singh, N. B.; Su, Ching Hua; Arnold, Brad; Choa, Fow-Sen

2017-01-01

There is a strong need for developing multifunctional materials to reduce the cost of applied material without compromising the performance of the detectors, devices and sensors. The materials design, processing, growth and fabrication of bulk and nanocrystals and fabrication into devices and sensors involve huge cost and resources including a multidisciplinary team of experts. Because of this reason, prediction of multifunctionality of materials before design and development should be evaluated. Chalcogenides and chalcopyrites are a very exciting class of materials for developing multifunctionality. Materials such as Gallium selenide GaSe and zinc selenide ZnSe have been proven to be excellent examples. GaSe is a layered material and very difficult to grow in large crystal. However, it's ternary and quaternary analogs such as thallium gallium selenide TlGaSe2, thallium gallium selenide sulfide TlGaSe2-xSs, thallium arsenic selenide Tl3AsSe3, silver gallium selenide AgGaGe3Se8, AgGaGe5Se12 and several others have shown great promise for multifunctionality. Several of these materials have shown good efficiency for frequency conversion (nonlinear optical NLO), electro-optic modulation, and acousto-optic tunable filters and imagers suitable for the visible, near-infrared wavelength, mid wave infrared (MWIR), long wave infrared (LWIR) and even up to Tera hertz wavelength (THW) regions. In addition, this class of materials have demonstrated low absorption coefficients and power handling capability in the systems. Also, these crystals do not require post growth annealing, show very large transparency range and fabricability.

Thymic pathologies in myasthenia gravis: a preoperative assessment of CAT scan and nuclear based imaging.

PubMed

Jordan, Berit; Kellner, Juliane; Jordan, Karin; Bähre, Manfred; Behrmann, Curd; Zierz, Stephan

2016-04-01

Precise diagnostic work up of a suspected thymic pathology in patients with myasthenia gravis (MG) is very important for potential surgical implications and further disease course. In this study the diagnostic value of combined preoperative radiological (CAT scan) and nuclear based imaging (octreotide and thallium scintigraphy) in patients with MG was evaluated. Twenty four patients were included. Histopathology revealed thymoma in nine patients, thymic carcinoma (TC) in one patient, lymphofollicular hyperplasia in seven patients, and involuted thymus in another seven patients. Diagnostic sensitivity for detecting thymoma/TC was 80 % in CAT scan as well as in somatostatin scintigraphy; the combination of both procedures reached 90 %. However, the diagnostic specifity to exclude thymoma in CAT scan was 100 % and in octreotide scintigraphy 85.7 %. Semiquantitative octreotide uptake significantly correlated with histological grading of thymoma/TC (r = 0.764) and histological proliferation rate Ki67 (r = 0.894). Thallium scintigraphy was positive only in one out of four thymoma cases. In this study, somatostatin scintigraphy has been shown to be a useful additional diagnostic technique in detecting thymic malignancies in patients with MG. These results might be especially helpful in patients with late onset MG as these patients are in general no candidates for thymectomy.

Type A behavior and the thallium stress test

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kahn, J.P.; Kornfeld, D.S.; Blood, D.K.

1982-11-01

Several recent studies have examined the association between Type A personality and coronary artery disease (CAD) by coronary angiography. Most of these studies have reported a significant association. The present study is an attempt at further confirmation, using a new non-invasive technique for measuring CAD. Subjects were 53 patients undergoing routine exercise stress tests with concomitant thallium-201 myocardial perfusion studies. Five aspects of Type A behavior were assessed by the use of the Rosenman-Friedman Semistructured Interview, and each was rated on a three-point scale. Severity of CAD was independently estimated on a four-point scale. Pearson correlation coefficients were separately computedmore » for patients with and without reported history of myocardial infarction (MI). For 37 patients without reported MI, CAD severity was significantly correlated with Overall Type A (r . -0.53), Vocal Characteristics (r . -0.53), Job Involvement (r . -0.36) and Aggressiveness (r . -0.48), but not Time Urgency (r . -0.25). For 16 patients with reported MI, CAD severity was significantly correlated with Job Involvement only (r . +0.49). The data are consistent with the association of Type A personality and coronary atherogenesis, but may also reflect Type A psychological and physiological characteristics. Future studies may be able to examine these and other aspects of Type A behavior using this noninvasive technique in more diverse patient populations.« less

Beta-decay measurements of neutron-rich thallium, lead, and bismuth by means of resonant laser ionisation

NASA Astrophysics Data System (ADS)

Franchoo, S.; de Witte, H.; Andreyev, A. N.; Cederka¨Ll, J.; Dean, S.; de Smet, A.; Eeckhaudt, S.; Fedorov, D. V.; Fedosseev, V. N.; G´Rska, M.; Huber, G.; Huyse, M.; Janas, Z.; Ko¨Ster, U.; Kurcewicz, W.; Kurpeta, J.; Mayer, P.; Płchocki, A.; van de Vel, K.; van Duppen, P.; Weissman, L.; Isolde Collaboration

2004-04-01

Neutron-rich thallium, lead, and bismuth isotopes were investigated at the ISOLDE facility. After mass separation and resonant laser ionisation of the produced activity, new spectroscopic data were obtained for 215,218Bi and 215Pb. An attempt to reach heavy thallium had to be abandoned because of a strong francium component in the beam that gave rise to a neutron background through (α,n) reactions on the aluminium walls of the experimental chamber.

Fate of Thallium(I) in Reverse Osmosis and Chlorinated Water Matrices

DTIC Science & Technology

2014-02-01

pKa of 13 for aquated Tl + , and that the precise nature of the hydrated ion in solution is not well established. 7 No further reactions of the Tl...of Tl + may be viewed as arising from a physical phenomenon. Because of the nature of the vial containing the thallium salt solution, it may be that...loss of thallium concentration was a result of adsorption of Tl + on the vial walls. Plastic vials are known to have significant adsorption

Thallium (Tl) sorption onto illite and smectite: Implications for Tl mobility in the environment

NASA Astrophysics Data System (ADS)

Martin, Loïc A.; Wissocq, Aubéry; Benedetti, M. F.; Latrille, Christelle

2018-06-01

Clay minerals play a relevant role in the transport and fate of trace elements in the environment. Though illite has been referred as an important Thallium (Tl) bearing phase in soils, mechanisms and affinity of thallium for clay minerals remain poorly known. This study investigated the sorption behavior of thallium as Tl(I) onto illite and smectite, two clay minerals occurring mainly in soils and sediments. Different sorption experiments were carried out under various pH conditions and Tl concentrations, in competition with sodium and calcium at a constant ionic strength of 0.01 mol L-1. Our results showed that illite displayed more affinity than smectite for thallium. With illite, the distribution coefficients (Kd in L kg-1) varied between 102.75 ± 0.17 and 104.0 ± 0.17 in Na solutions versus between 102.25 ± 0.17 and 103.0 ± 0.17 in Ca solutions, depending on pH. With smectite, Kd (in L kg-1) ranged between 102.50 ± 0.16 and 103.20 ± 0.16 and between 101.25 ± 0.16 and 101.95 ± 0.16 in Na and Ca solutions, respectively. Sorption behavior was described with the Multi-Site Ion Exchanger model and selectivity coefficients with respect to protons were calculated for the first time. In all cases, independently of clay mineral and background electrolyte, low capacity but highly reactive sites were dominant in thallium uptake, highlighting Tl affinity for those sites. Moreover, the exchangeable and reversible interactions between Tl+ and clays reactive sites suggested that in changing conditions, thallium could be released in solution. The role of clay minerals in thallium environmental cycle is evident and confirmed illite to be a dominant Tl bearing phase, in some environment competing with manganese oxides. Compared to others Tl bearing mineral phases, clays are ranked as follows: MnO2 > illite > smectite ∼ ferrihydrite ≥ Al2O3 ∼ goethite > SiO2. Finally, over the three monovalent cations (Tl, Rb, Cs) Tl is the one less sorbed on illite independently of the background cations.

Myocardial viability assessment after acute myocardial infarction: low-dose dobutamine echocardiography versus rest-redistribution thallium-201 SPECT.

PubMed

Castini, D; Bestetti, A; Garbin, M; Di Leo, C; Bigi, R; Sponzilli, C; Concardi, G; Gioventù, M; Tarolo, G L; Lombardi, F; Fiorentini, C

1999-09-01

The presence of tissue viability is of great importance in the prognostic work-up of patients recovering from acute myocardial infarction. However, uncertainty still exists concerning the optimal tool for its assessment. The present study was undertaken in order to compare low-dose dobutamine echocardiography and rest-redistribution thallium SPECT for predicting late improvement of regional left ventricular function after acute myocardial infarction. Fifteen patients undergoing coronary angiography, low-dose dobutamine echocardiography and rest-redistribution thallium SPECT after thrombolyzed anterior acute myocardial infarction were studied. A 3 month follow-up echocardiogram was performed in all patients and 9 underwent coronary revascularization. A significant (> or = 70%) residual stenosis of the infarct-related artery was present in 14 patients, whilst a total occlusion was observed in 1. At 3 month follow-up, 41% of the dyssynergic segments improved. The sensitivity, specificity and accuracy for late wall motion improvement was 61, 89 and 77% for low-dose dobutamine echocardiography and, respectively, 76, 45 and 58% for rest-redistribution thallium SPECT. Tissue viability was detected in 65 and 31% of dyssynergic segments by rest-redistribution thallium SPECT and low-dose dobutamine echocardiography, respectively (p < 0.001). The agreement between the two techniques was 48%. Low-dose dobutamine echocardiography is more accurate than rest-redistribution thallium SPECT for predicting 3 month wall motion improvement in patients with acute anterior myocardial infarction, mainly due to its significantly better specificity.

Patients with stable chronic obstructive pulmonary disease can safely undergo intravenous dipyridamole thallium-201 imaging.

PubMed

Shaffer, J; Simbartl, L; Render, M L; Snow, E; Chaney, C; Nishiyama, H; Rauf, G C; Wexler, L F

1998-08-01

Patients with chronic obstructive pulmonary disease are usually excluded from intravenous dipyridamole thallium-201 testing. We developed a nurse-administered protocol to screen and pretreat patients so they could be safely tested. We prospectively screened patients referred for intravenous dipyridamole thallium testing and retrospectively reviewed a comparison group of patients who had undergone intravenous dipyridamole testing before our bronchospasm protocol. We studied 492 consecutive patients referred for intravenous dipyridamole thallium testing, separating those with complete data (n = 451) into two groups: group A (n = 72), patients assessed to be at risk for intravenous dipyridamole-induced bronchospasm who received our bronchospasm treatment protocol; and group B (n = 379), patients assessed to be free of risk, who did not receive our bronchospasm protocol. Group C (n = 89) was a retrospective comparison group of patients who had undergone intravenous dipyridamole testing before initiation of the protocol. Patients were considered at risk for an adverse event if any of the following were present: peak flow < or =400 ml at the time of the test (spirometry by nurse) that increased to >400 ml after bronchodilator treatment, wheezing audible with stethoscope, history of chronic obstructive pulmonary disease or asthma or dyspnea on exertion at less than four blocks, or resting respiratory rate >18 breaths/min. The test was considered contraindicated if resting oxygen saturation was <85%, respiratory rate < or =36 breaths/min, or peak flow measured by peak flowmeter <400 ml after bronchodilator inhalant (albuterol or metaproterenol sulfate by spacer) at a dose of up to six puffs. One minute after injections of thallium-201, patients at risk were given 50 mg aminophylline by slow intravenous injection. We looked for major and minor adverse effects and divided them into three categories: (1) minor events (transient headache, abdominal discomfort, or nausea), wheezing (audible by stethoscope but without marked respiratory distress), (2) marked events (severe bronchospasm or severe ischemia defined as wheezing audible with or without stethoscope, respiratory rate >20 breaths/min or increased by 10 from pretest evaluation, oxygen desaturation to <90%, hypoventilation [reduced respiratory rate with decreased mental status], respiratory arrest, chest pain, horizontal ST-segment depression > or =1 mm on the electrocardiogram in any lead, symptomatic hypotension), or (3) other intravenous dipyridamole-induced side effects (persistent headache, dizziness, flushing, nausea, dyspnea, and ischemic chest pain) or anginal equivalent. The protocol properly identified patients with impaired pulmonary function. There was no difference in the frequency of adverse marked events among groups A, B, or C (1 % vs 4% vs 2%, p = 0.25). Patients in group A had more minor side effects than those in group B (53% vs 35%, p = 0.004). Specifically, patients in group A were more likely to wheeze (39% vs 1 %, p = <0.001), but wheezing in group A was self-limited or responded to treatment as described in the protocol. The prevalence of positive thallium-201 scans in group A (44%) compared with group C (49%) was not different (p = 0.15). A nurse-administered risk assessment and pretreatment protocol (1) properly identified patients with impaired pulmonary function, (2) permitted completion of intravenous dipyridamole testing in patients at risk for bronchospasm without an increased incidence of marked adverse events, and (3) did not appear to influence the interpretation of the thallium test.

Thallium selenite

Integrated Risk Information System (IRIS)

Thallium selenite ; CASRN 12039 - 52 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogen

Thallium oxide

Integrated Risk Information System (IRIS)

Thallium oxide ; CASRN 1314 - 32 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

Influence of the Dirac-Hartree-Fock starting potential on the parity-nonconserving electric-dipole-transition amplitudes in cesium and thallium

NASA Technical Reports Server (NTRS)

Perger, W. F.; Das, B. P.

1987-01-01

The parity-nonconserving electric-dipole-transition amplitudes for the 6s1/2-7s1/2 transition in cesium and the 6p1/2-7p1/2 transition in thallium have been calculated by the Dirac-Hartree-Fock method. The effects of using different Dirac-Hartree-Fock atomic core potentials are examined and the transition amplitudes for both the length and velocity gauges are given. It is found that the parity-nonconserving transition amplitudes exhibit a greater dependence on the starting potential for thallium than for cesium.

Spectrofluorimetric determination of thallium in silicate rocks with rhodamine b in the presence of aluminum chloride

USGS Publications Warehouse

Shnepfe, M.M.

1975-01-01

A sensitive spectrofluorimetric procedure with rhodamine B in the presence of aluminum chloride is given for determining submicrogram and microgram quantities of thallium in silicate rocks. Samples are decomposed with a mixture of hydrofluoric and nitric acids and then treated with hydrochloric acid. Thallium is extracted as its dithizonate with chloroform from an alkaline medium containing ascorbate, citrate, and cyanide and then back-extracted with dilute nitric acid. After destruction of the organic matter and treatment with bromine, hydrochloric acid, aluminum chloride, and rhodamine B, the {A table is presented}. ?? 1975.

Nuclear Cardiology Practice in Asia: Analysis of Radiation Exposure and Best Practice for Myocardial Perfusion Imaging　- Results From the IAEA Nuclear Cardiology Protocols Cross-Sectional Study (INCAPS).

PubMed

Pascual, Thomas N B; Mercuri, Mathew; El-Haj, Noura; Bom, Henry Hee-Sung; Lele, Vikram; Al-Mallah, Mouaz H; Luxenburg, Osnat; Karthikeyan, Ganesan; Vitola, Joao; Mahmarian, John J; Better, Nathan; Shaw, Leslee J; Rehani, Madan M; Kashyap, Ravi; Paez, Diana; Dondi, Maurizio; Einstein, Andrew J

2017-03-24

This paper examines the current status of radiation exposure to patients in myocardial perfusion imaging (MPI) in Asia.Methods and Results:Laboratories voluntarily provided information on MPI performed over a 1-week period. Eight best practice criteria regarding MPI were predefined by an expert panel. Implementation of ≥6 best practices (quality index [QI] ≥6) was pre-specified as a desirable goal for keeping radiation exposure at a low level. Radiation effective dose (ED) in 1,469 patients and QI of 69 laboratories in Asia were compared against data from 239 laboratories in the rest of the world (RoW). Mean ED was significantly higher in Asia (11.4 vs. 9.6 mSv; P<0.0001), with significantly lower doses in South-East vs. East Asia (9.7 vs. 12.7 mSv; P<0.0001). QI in Asia was lower than in RoW. In comparison with RoW, Asian laboratories used thallium more frequently, used weight-based technetium dosing less frequently, and trended towards a lower rate of stress-only imaging. MPI radiation dose in Asia is higher than that in the RoW and linked to less consistent use of laboratory best practices such as avoidance of thallium, weight-based dosing, and use of stress-only imaging. Given that MPI is performed in Asia within a diverse array of medical contexts, laboratory-specific adoption of best practices offers numerous opportunities to improve quality of care.

Thallium (I), soluble salts

Integrated Risk Information System (IRIS)

EPA / 635 / R - 08 / 001F www.epa.gov / iris TOXICOLOGICAL REVIEW OF THALLIUM AND COMPOUNDS ( CAS No . 7440 - 28 - 0 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) September 2009 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document ha

IRIS Toxicological Review of Thallium and Compounds (Final Report)

EPA Science Inventory

EPA has finalized the Toxicological Review of Thallium and Compounds: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health.

Thallium-201 per rectum for the diagnosis of cirrhosis in patients with asymptomatic chronic hepatitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

D'Arienzo, A.; Celentano, L.; Scuotto, A.

1988-07-01

In normal subjects, thallium-201, administered per rectum, is taken up mainly by the liver (heart/liver ratio in normal subjects: 0.04 to 0.12). It has been claimed that an increased heart/liver ratio is suggestive of portal-caval shunting and portal hypertension. To evaluate the possibility of using thallium-201 as a test to diagnose cirrhosis, we administered this substance per rectum to 33 patients with biochemical evidence, but no clinical symptoms, of liver disease. Laparoscopy and liver biopsy revealed chronic active hepatitis without cirrhosis in 18 patients, and chronic active hepatitis with cirrhosis in the others. The results of conventional liver function testsmore » were similar in both groups. A significant difference, however, was found between the means of fasting serum bile acid concentrations (9.8 +/- 3.2 and 18.3 +/- 4.2 microM per liter) in chronic active hepatitis without cirrhosis and cirrhotic patients, and between the means of the heart/liver ratios 20 min after thallium-201 administration (heart/liver: 0.09 +/- 0.03 and 0.54 +/- 0.13, respectively). Unlike the serum bile acid concentration which gave some overlapping values, the thallium-201 test clearly distinguished the chronic active hepatitis without cirrhosis group from the cirrhotics. In the cirrhotic group, there was a significant correlation between the heart/liver ratio and signs of portal hypertension such as esophageal varices, increased diameter of the vena porta and hypersplenism. The thallium-201 test is therefore useful in discriminating between chronic active hepatitis with and without cirrhosis in clinically asymptomatic subjects with biochemical evidence of moderate liver function impairment. A heart/liver uptake ratio much higher than normal (above 0.30) strongly suggests the development of hepatic cirrhosis.« less

IN VIVO SYNCHROTRON INVESTIGATION OF THALLIUM HYPERACCUMULATION - I

EPA Science Inventory

Thallium (TI) is a metal of great toxicological concern and its prevalence in the natural environment has steadily increased as a result of manufacturing and combustion practices. Due to its low natural abundance and the increasing demand, TI recovery and reuse could be a profita...

Production of .sup.203 Pb-tris-hydroxymethyl amino methane

DOEpatents

Lambrecht, Richard M.; Packer, Samuel; Merrill, Jerald C.; Atkins, Harold L.; Wolf, Alfred P.; Bradley-Moore, Patrick R.

1977-01-01

.sup.203 Pb-tris complex injected for use in the detection and localization of tumors. The lead-203 is produced from the deuteron bombardment of a thallium target and chemically separated from the thallium. The tris is added which complexes with the lead-203.

IN VIVO SYNCHROTRON ANALYSIS OF THALLIUM IN IBERIS INTERMEDIA

EPA Science Inventory

Thallium is a metal of great toxicological concern and its prevalence in the natural environment has steadily increased as a result of manufacturing and combustion practices. Due to its low natural abundance and the increasing demand, TI is the fourth most expensive metal, thus, ...

Metalorganic deposition method for forming epitaxial thallium-based copper oxide superconducting films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olsen, W.L.; Eddy, M.M.; Hammond, R.B.

1991-12-10

This patent describes a method for producing a superconducting article comprising an oriented metal oxide superconducting layer containing thallium, optionally calcium, barium and copper, the layer being at least 30 {Angstrom} and having a c-axis oriented normal to a crystalline substrate surface. It comprises coating the crystalline substrate surface with a solution of thallium, optionally calcium, barium and copper carboxylate soaps dispersed in a medium of hydrocarbons of halohydrocarbons with a stoichiometric metal ratio to form the oxide superconducting layer, prepyrolyzing the soaps coated on the substrate at a temperature of 350{degrees} C. or less in an oxygen containing atmosphere,more » and pyrolyzing the soaps at a temperature in the range of 800{degrees} - 900{degrees} C. in the presence of oxygen and an overpressure of thallium for a sufficient time to produce the superconducting layer on the substrate, wherein usable portions of the superconducting layer are epitaxial to the substrate.« less

Reflective and Non-conscious Responses to Exercise Images

PubMed Central

Cope, Kathryn; Vandelanotte, Corneel; Short, Camille E.; Conroy, David E.; Rhodes, Ryan E.; Jackson, Ben; Dimmock, James A.; Rebar, Amanda L.

2018-01-01

Images portraying exercise are commonly used to promote exercise behavior and to measure automatic associations of exercise (e.g., via implicit association tests). The effectiveness of these promotion efforts and the validity of measurement techniques partially rely on the untested assumption that the images being used are perceived by the general public as portrayals of exercise that is pleasant and motivating. The aim of this study was to investigate how content of images impacted people's automatic and reflective evaluations of exercise images. Participants (N = 90) completed a response time categorization task (similar to the implicit association test) to capture how automatically people perceived each image as relevant to Exercise or Not exercise. Participants also self-reported their evaluations of the images using visual analog scales with the anchors: Exercise/Not exercise, Does not motivate me to exercise/Motivates me to exercise, Pleasant/Unpleasant, and Energizing/Deactivating. People tended to more strongly automatically associate images with exercise if the images were of an outdoor setting, presented sport (as opposed to active labor or gym-based) activities, and included young (as opposed to middle-aged) adults. People tended to reflectively find images of young adults more motivating and relevant to exercise than images of older adults. The content of exercise images is an often overlooked source of systematic variability that may impact measurement validity and intervention effectiveness. PMID:29375419

Reflective and Non-conscious Responses to Exercise Images.

PubMed

Cope, Kathryn; Vandelanotte, Corneel; Short, Camille E; Conroy, David E; Rhodes, Ryan E; Jackson, Ben; Dimmock, James A; Rebar, Amanda L

2017-01-01

Images portraying exercise are commonly used to promote exercise behavior and to measure automatic associations of exercise (e.g., via implicit association tests). The effectiveness of these promotion efforts and the validity of measurement techniques partially rely on the untested assumption that the images being used are perceived by the general public as portrayals of exercise that is pleasant and motivating. The aim of this study was to investigate how content of images impacted people's automatic and reflective evaluations of exercise images. Participants ( N = 90) completed a response time categorization task (similar to the implicit association test) to capture how automatically people perceived each image as relevant to Exercise or Not exercise . Participants also self-reported their evaluations of the images using visual analog scales with the anchors: Exercise / Not exercise, Does not motivate me to exercise / Motivates me to exercise, Pleasant / Unpleasant , and Energizing/Deactivating . People tended to more strongly automatically associate images with exercise if the images were of an outdoor setting, presented sport (as opposed to active labor or gym-based) activities, and included young (as opposed to middle-aged) adults. People tended to reflectively find images of young adults more motivating and relevant to exercise than images of older adults. The content of exercise images is an often overlooked source of systematic variability that may impact measurement validity and intervention effectiveness.

Role of valence electrons in phase transformation kinetics of thallium and its dilute alloys

NASA Technical Reports Server (NTRS)

Ahmed, R.; Ahmed, S.

1991-01-01

The kinetics of the phase transformation of thallium and its dilute alloys were investigated using XRD and calorimetry. Pure thallium exhibits a beta(bcc) to alpha(hcp) phase transformation on cooling at 508 K. With alloying additions, the crystal structure for each phase does not change, although the size of the unit cell increases. The enthalpy and the temperature of phase transformation of each alloy have been determined. The chemical free energy change associated with the phase transformation of each alloy was calculated. The valence electrons make an outstanding contribution to the chemical free energy change required for the phase change.

Preparation of Bismuth- and Thallium-Based Cuprate Superconductors

DTIC Science & Technology

1991-10-01

heating times, the use of gold foil wrappings, and, possibly most impor- tantly, a decrease in thallium volatility according to the principle of Le ... Chatelier (27). If the reactions are carried out in nonporous sleeves with exiting gases passed through multiple traps filled with basic peroxide

IN-VIVO SYNCHROTRON ANALYSIS OF THALLIUM IN IBERIS INTERMEDIA

EPA Science Inventory

Thallium (TI) is a metal of great toxicological concern and its prevalence in the natural environment has steadily increased as a result of manufacturing and combustion practices. Due to its low natural abundance and the increasing demand, TI is the fourth most expensive metal, t...

[The development of a computer model in the quantitative assessment of thallium-201 myocardial scintigraphy].

PubMed

Raineri, M; Traina, M; Rotolo, A; Candela, B; Lombardo, R M; Raineri, A A

1993-05-01

Thallium-201 scintigraphy is a widely used noninvasive procedure for the detection and prognostic assessment of patients with suspected or proven coronary artery disease. Thallium uptake can be evaluated by a visual analysis or by a quantitative interpretation. Quantitative scintigraphy enhances disease detection in individual coronary arteries, provides a more precise estimate of the amount of ischemic myocardium, distinguishing scar from hypoperfused tissue. Due to the great deal of data, analysis, interpretation and comparison of thallium uptake can be very complex. We designed a computer-based system for the interpretation of quantitative thallium-201 scintigraphy data uptake. We used a database (DataEase 4.2-DataEase Italia). Our software has the following functions: data storage; calculation; conversion of numerical data into different definitions classifying myocardial perfusion; uptake data comparison; automatic conclusion; comparison of different scintigrams for the same patient. Our software is made up by 4 sections: numeric analysis, descriptive analysis, automatic conclusion, clinical remarks. We introduced in the computer system appropriate information, "logical paths", that use the "IF ... THEN" rules. The software executes these rules in order to analyze the myocardial regions in the 3 phases of scintigraphic analysis (stress, redistribution, re-injection), in the 3 projections (LAO 45 degrees, LAT,ANT), considering our uptake cutoff, obtaining, finally, the automatic conclusions. For these reasons, our computer-based system could be considered a real "expert system".

Thallium bromide radiation detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shah, K.S.; Lund, J.C.; Olschner, F.

1989-02-01

Radiation detectors have been fabricated from crystals of the semiconductor material thallium bromide (TlBr) and the performance of these detectors as room temperature photon spectrometers has been measured. These detectors exhibit improved energy resolution over previously reported TlBr detectors. These results indicate that TlBr is a very promising radiation detector material.

Redistribution on the thallium scan in myocardial sarcoidosis: concise communication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makler, P.T.; Lavine, S.J.; Denenberg, B.S.

1981-05-01

Resting and redistribution thallium studies were performed in four young patients with sarcoidosis to evaluate the possibility of myocardial involvement. In each case the resting scan showed marked defects that resolved on the redistribution studies. In a different patient population, these results would have implied significant coronary artery disease.

IN VIVO SYNCHROTRON STUDY OF THALLIUM SPECIATION AND COMPARTMENTATION IN IBERIS INTERMEDIA

EPA Science Inventory

Thallium (TI) is a metal of great toxicological concern and its prevalence in the natural environment has steadily increased as a result of manufacturing and combustion practices. Due to its low natural abundance and increasing demand, TI is the fourth most expensive metal, thus,...

meso-Octamethylcalix[4]pyrrole as an effective macrocyclic receptor for the univalent thallium cation in the gas phase: Experimental and theoretical study

NASA Astrophysics Data System (ADS)

Polášek, Miroslav; Makrlík, Emanuel; Kvíčala, Jaroslav; Křížová, Věra; Vaňura, Petr

2018-02-01

By using electrospray ionization mass spectrometry (ESI-MS), it was proven experimentally that the univalent thallium cation (Tl+) forms with meso-octamethylcalix[4]pyrrole (1) the cationic complex species 1 Tl+. When this kinetically stable cation-π complex 1 Tl+ is collisionally activated, it decomposes by elimination of the whole ligand 1 or small meso-octamethylcalix[4]pyrrole fragments. Further, applying quantum chemical DFT calculations, four different conformations of the resulting complex 1 Tl+ were derived. It means that under the present experimental conditions, this ligand 1 can be considered as a very effective macrocyclic receptor for the thallium cation.

Thallium Bromide as an Alternative Material for Room-Temperature Gamma-Ray Spectroscopy and Imaging

NASA Astrophysics Data System (ADS)

Koehler, William

Thallium bromide is an attractive material for room-temperature gamma-ray spectroscopy and imaging because of its high atomic number (Tl: 81, Br: 35), high density (7.56 g/cm3), and a wide bandgap (2.68 eV). In this work, 5 mm thick TlBr detectors achieved 0.94% FWHM at 662 keV for all single-pixel events and 0.72% FWHM at 662 keV from the best pixel and depth using three-dimensional position sensing technology. However, these results were limited to stable operation at -20°C. After days to months of room-temperature operation, ionic conduction caused these devices to fail. Depth-dependent signal analysis was used to isolate room-temperature degradation effects to within 0.5 mm of the anode surface. This was verified by refabricating the detectors after complete failure at room temperature; after refabrication, similar performance and functionality was recovered. As part of this work, the improvement in electron drift velocity and energy resolution during conditioning at -20°C was quantified. A new method was developed to measure the impurity concentration without changing the gamma ray measurement setup. The new method was used to show that detector conditioning was likely the result of charged impurities drifting out of the active volume. This space charge reduction then caused a more stable and uniform electric field. Additionally, new algorithms were developed to remove hole contributions in high-hole-mobility detectors to improve depth reconstruction. These algorithms improved the depth reconstruction (accuracy) without degrading the depth uncertainty (precision). Finally, spectroscopic and imaging performance of new 11 x 11 pixelated-anode TlBr detectors was characterized. The larger detectors were used to show that energy resolution can be improved by identifying photopeak events from their Tl characteristic x-rays.

Diagnostic value of thallium-201 myocardial perfusion IQ-SPECT without and with computed tomography-based attenuation correction to predict clinically significant and insignificant fractional flow reserve

PubMed Central

Tanaka, Haruki; Takahashi, Teruyuki; Ohashi, Norihiko; Tanaka, Koichi; Okada, Takenori; Kihara, Yasuki

2017-01-01

Abstract The aim of this study was to clarify the predictive value of fractional flow reserve (FFR) determined by myocardial perfusion imaging (MPI) using thallium (Tl)-201 IQ-SPECT without and with computed tomography-based attenuation correction (CT-AC) for patients with stable coronary artery disease (CAD). We assessed 212 angiographically identified diseased vessels using adenosine-stress Tl-201 MPI-IQ-SPECT/CT in 84 consecutive, prospectively identified patients with stable CAD. We compared the FFR in 136 of the 212 diseased vessels using visual semiquantitative interpretations of corresponding territories on MPI-IQ-SPECT images without and with CT-AC. FFR inversely correlated most accurately with regional summed difference scores (rSDS) in images without and with CT-AC (r = −0.584 and r = −0.568, respectively, both P < .001). Receiver-operating characteristics analyses using rSDS revealed an optimal FFR cut-off of <0.80 without and with CT-AC. Although the diagnostic accuracy of FFR <0.80 did not significantly differ, FFR ≥0.82 was significantly more accurate with, than without CT-AC. Regions with rSDS ≥2 without or with CT-AC predicted FFR <0.80, and those with rSDS ≤1 without and with CT-AC predicted FFR ≥0.81, with 73% and 83% sensitivity, 84% and 67% specificity, and 79% and 75% accuracy, respectively. Although limited by the sample size and the single-center design, these findings showed that the IQ-SPECT system can predict FFR at an optimal cut-off of <0.80, and we propose a novel application of CT-AC to MPI-IQ-SPECT for predicting clinically significant and insignificant FFR even in nonobese patients. PMID:29390486

Impact of scar thickness on the assessment of viability using dobutamine echocardiography and thallium single-photon emission computed tomography: a comparison with contrast-enhanced magnetic resonance imaging.

PubMed

Nelson, Charles; McCrohon, Jane; Khafagi, Frederick; Rose, Stephen; Leano, Rodel; Marwick, Thomas H

2004-04-07

We sought to determine whether the transmural extent of scar (TES) explains discordances between dobutamine echocardiography (DbE) and thallium single-photon emission computed tomography (Tl-SPECT) in the detection of viable myocardium (VM). Discrepancies between DbE and Tl-SPECT are often attributed to differences between contractile reserve and membrane integrity, but may also reflect a disproportionate influence of nontransmural scar on thickening at DbE. Sixty patients (age 62 +/- 12 years; 10 women and 50 men) with postinfarction left ventricular dysfunction underwent standard rest-late redistribution Tl-SPECT and DbE. Viable myocardium was identified when dysfunctional segments showed Tl activity >60% on the late-redistribution image or by low-dose augmentation at DbE. Contrast-enhanced magnetic resonance imaging (ceMRI) was used to divide TES into five groups: 0%, <25%, 26% to 50%, 51% to 75%, and >75% of the wall thickness replaced by scar. As TES increased, both the mean Tl uptake and change in wall motion score decreased significantly (both p < 0.001). However, the presence of subendocardial scar was insufficient to prevent thickening; >50% of segments still showed contractile function with TES of 25% to 75%, although residual function was uncommon with TES >75%. The relationship of both tests to increasing TES was similar, but Tl-SPECT identified VM more frequently than DbE in all groups. Among segments without scar or with small amounts of scar (<25% TES), >50% were viable by SPECT. Both contractile reserve and perfusion are sensitive to the extent of scar. However, contractile reserve may be impaired in the face of no or minor scar, and thickening may still occur with extensive scar.

Nuclear myocardial perfusion imaging using thallium-201 with a novel multifocal collimator SPECT/CT: IQ-SPECT versus conventional protocols in normal subjects.

PubMed

Matsuo, Shinro; Nakajima, Kenichi; Onoguchi, Masahisa; Wakabayash, Hiroshi; Okuda, Koichi; Kinuya, Seigo

2015-06-01

A novel multifocal collimator, IQ-SPECT (Siemens) consists of SMARTZOOM, cardio-centric and 3D iterative SPECT reconstruction and makes it possible to perform MPI scans in a short time. The aims are to delineate the normal uptake in thallium-201 ((201)Tl) SPECT in each acquisition method and to compare the distribution between new and conventional protocol, especially in patients with normal imaging. Forty patients (eight women, mean age of 75 years) who underwent myocardial perfusion imaging were included in the study. All patients underwent one-day protocol perfusion scan after an adenosine-stress test and at rest after administering (201)Tl and showed normal results. Acquisition was performed on a Symbia T6 equipped with a conventional dual-headed gamma camera system (Siemens ECAM) and with a multifocal SMARTZOOM collimator. Imaging was performed with a conventional system followed by IQ-SPECT/computed tomography (CT). Reconstruction was performed with or without X-ray CT-derived attenuation correction (AC). Two nuclear physicians blinded to clinical information interpreted all myocardial perfusion images. A semi-quantitative myocardial perfusion was analyzed by a 17-segment model with a 5-point visual scoring. The uptake of each segment was measured and left ventricular functions were analyzed by QPS software. IQ-SPECT provided good or excellent image quality. The quality of IQ-SPECT images without AC was similar to those of conventional LEHR study. Mid-inferior defect score (0.3 ± 0.5) in the conventional LEHR study was increased significantly in IQ-SPECT with AC (0 ± 0). IQ-SPECT with AC improved the mid-inferior decreased perfusion shown in conventional images. The apical tracer count in IQ-SPECT with AC was decreased compared to that in LEHR (0.1 ± 0.3 vs. 0.5 ± 0.7, p < 0.05). The left ventricular ejection fraction from IQ-SPECT was significantly higher than that from the LEHR collimator (p = 0.0009). The images of IQ-SPECT acquired in a short time are equivalent to that of conventional LEHR. The results indicated that the IQ-SPECT system with AC is capable of correcting inferior artifacts with high image quality.

Thallium-201 for cardiac stress tests: residual radioactivity worries patients and security.

PubMed

Geraci, Matthew J; Brown, Norman; Murray, David

2012-12-01

A 47-year-old man presented to the Emergency Department (ED) in duress and stated he was "highly radioactive." There were no reports of nuclear disasters, spills, or mishaps in the local area. This report discusses the potential for thallium-201 (Tl-201) patients to activate passive radiation alarms days to weeks after nuclear stress tests, even while shielded inside industrial vehicles away from sensors. Characteristics of Tl-201, as used for medical imaging, are described. This patient was twice detained by Homeland Security Agents and searched after he activated radiation detectors at a seaport security checkpoint. Security agents deemed him not to be a threat, but they expressed concern regarding his health and level of personal radioactivity. The patient was subsequently barred from his job and sent to the hospital. Tl-201 is a widely used radioisotope for medical imaging. The radioactive half-life of Tl-201 is 73.1h, however, reported periods of extended personal radiation have been seen as far out as 61 days post-administration. This case describes an anxious, but otherwise asymptomatic patient presenting to the ED with detection of low-level personal radiation. Documentation should be provided to and carried by individuals receiving radionuclides for a minimum of five to six half-lives of the longest-lasting isotope provided. Patients receiving Tl-201 should understand the potential for security issues; reducing probable tense moments, confusion, and anxiety to themselves, their employers, security officials, and ED staff. Copyright © 2012 Elsevier Inc. All rights reserved.

Determination of thallium at ultra-trace levels in water and biological samples using solid phase spectrophotometry

NASA Astrophysics Data System (ADS)

Amin, Alaa S.; El-Sharjawy, Abdel-Azeem M.; Kassem, Mohammed A.

2013-06-01

A new simple, very sensitive, selective and accurate procedure for the determination of trace amounts of thallium(III) by solid-phase spectrophotometry (SPS) has been developed. The procedure is based on fixation of Tl(III) as quinalizarin ion associate on a styrene-divinylbenzene anion-exchange resin. The absorbance of resin sorbed Tl(III) ion associate is measured directly at 636 and 830 nm. Thallium(I) was determined by difference measurements after oxidation of Tl(I) to Tl(III) with bromine. Calibration is linear over the range 0.5-12.0 μg L-1 of Tl(III) with relative standard deviation (RSD) of 1.40% (n = 10). The detection and quantification limits are 150 and 495 ng L-1 using 0.6 g of the exchanger. The molar absorptivity and Sandell sensitivity are also calculated and found to be 1.31 × 107 L mol-1 cm-1 and 0.00156 ng cm-2, respectively. The proposed procedure has been successfully applied to determine thallium in water, urine and serum samples.

Determination of thallium at ultra-trace levels in water and biological samples using solid phase spectrophotometry.

PubMed

Amin, Alaa S; El-Sharjawy, Abdel-Azeem M; Kassem, Mohammed A

2013-06-01

A new simple, very sensitive, selective and accurate procedure for the determination of trace amounts of thallium(III) by solid-phase spectrophotometry (SPS) has been developed. The procedure is based on fixation of Tl(III) as quinalizarin ion associate on a styrene-divinylbenzene anion-exchange resin. The absorbance of resin sorbed Tl(III) ion associate is measured directly at 636 and 830 nm. Thallium(I) was determined by difference measurements after oxidation of Tl(I) to Tl(III) with bromine. Calibration is linear over the range 0.5-12.0 μg L(-1) of Tl(III) with relative standard deviation (RSD) of 1.40% (n=10). The detection and quantification limits are 150 and 495 ng L(-1) using 0.6 g of the exchanger. The molar absorptivity and Sandell sensitivity are also calculated and found to be 1.31×10(7) L mol(-1)cm(-1) and 0.00156 ng cm(-2), respectively. The proposed procedure has been successfully applied to determine thallium in water, urine and serum samples. Copyright © 2013 Elsevier B.V. All rights reserved.

Reference Data for the Density and Viscosity of Liquid Cadmium, Cobalt, Gallium, Indium, Mercury, Silicon, Thallium, and Zinc

NASA Astrophysics Data System (ADS)

Assael, Marc J.; Armyra, Ivi J.; Brillo, Juergen; Stankus, Sergei V.; Wu, Jiangtao; Wakeham, William A.

2012-09-01

The available experimental data for the density and viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc have been critically examined with the intention of establishing both a density and a viscosity standard. All experimental data have been categorized into primary and secondary data according to the quality of measurement, the technique employed and the presentation of the data, as specified by a series of criteria. The proposed standard reference correlations for the density of liquid cadmium, cobalt, gallium, indium, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 0.6, 2.1, 0.4, 0.5, 2.2, 0.9, and 0.7, respectively. In the case of mercury, since density reference values already exist, no further work was carried out. The standard reference correlations for the viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 9.4, 14.0, 13.5, 2.1, 7.3, 15.7, 5.1, and 9.3, respectively.

Reversibility by dipyridamole of thallium-201 myocardial scan defects in patients with sarcoidosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tellier, P.; Paycha, F.; Antony, I.

1988-08-01

In order to clarify the significance of anginal pain and myocardial thallium-201 scan defects in cardiac sarcoidosis, the pharmacologic effect of dipyridamole on myocardial perfusion was assessed by planar thallium-201 myocardial scintigraphy in patients with sarcoidosis. Thallium-201 myocardial scintigraphy was performed at rest and after 0.56 mg/kg intravenous dipyridamole during four minutes in 16 patients with sarcoidosis. The myocardial scan (45-degree and 70-degree left anterior oblique, and anterior views) was divided into 15 segments. Results were evaluated by the number of segmental defects and with a global perfusion score (from 0 to 60) by a semi-quantitative index depending on themore » size and severity of myocardial thallium-201 defects. Thirteen of the 16 patients showed partial or total reversion of their thallium-201 defects on redistribution scanning either at rest or after dipyridamole. The mean (+/- SD) number of myocardial perfusion defects that were present in all the patients decreased from 5.31 +/- 1.78 at rest to 3.25 +/- 2.52 after redistribution (p less than 0.001) and to 2.19 +/- 2.10 after dipyridamole (p less than 0.001). The mean global perfusion score increased from 53.2 +/- 3.0 at rest to 56.2 +/- 2.9 after redistribution (p less than 0.001) and to 57.2 +/- 2.7 after dipyridamole (p less than 0.001). A significant correlation (r = 0.82, p less than 0.001) was found between the increase of global perfusion score on redistribution and after dipyridamole. The reversibility of myocardial scan defects is a common finding in sarcoidosis. It makes unlikely the role of scar fibrosis or extensive confluent granulomas as a mechanism for such defects. The effect of dipyridamole suggests the presence of reversible disorders lying at the coronary microvascular level.« less

Recent developments of cyclotron produced radionuclides for nuclear cardiology

NASA Astrophysics Data System (ADS)

Kulkarni, P. V.; Jansen, D. E.; Corbett, J. R.

1987-04-01

For over a decade myocardial perfusion imaging with thallium-201, a cyclotron product, has been routinely used in clinical medicine. Recent advances have allowed the efficient production of very high purity (> 99.8%) iodine-123. New metabolically active 123I labeled radiopharmaceuticals, including alkyl and phenyl fatty acids, and norepinephrine analogs, have been developed and are undergoing clinical trials. Fab' fragments of monoclonal antibodies to cardiac myosin have been labeled with indium-111 ( 111In) and are undergoing clinical evaluation for imaging myocardial infarcts. Monoclonal antibodies to platelets, fibrin, and the thrombolytic agent, tissue plasminogen activator (TPA), have recently been labeled with 111In. Together these developments in radiotracers and instrumentation should have a significant impact on the future of cardiovascular nuclear medicine. This manuscript will discuss developments in single photon emitting radiotracers for myocardial imaging.

Cardiac phase-synchronized myocardial thallium-201 single-photon emission tomography using list mode data acquisition and iterative tomographic reconstruction.

PubMed

Vemmer, T; Steinbüchel, C; Bertram, J; Eschner, W; Kögler, A; Luig, H

1997-03-01

The purpose of this study was to determine whether data acquisition in the list mode and iterative tomographic reconstruction would render feasible cardiac phase-synchronized thallium-201 single-photon emission tomography (SPET) of the myocardium under routine conditions without modifications in tracer dose, acquisition time, or number of steps of the a gamma camera. Seventy non-selected patients underwent 201T1 SPET imaging according to a routine protocol (74 MBq/2 mCi 201T1, 180 degrees rotation of the gamma camera, 32 steps, 30 min). Gamma camera data, ECG, and a time signal were recorded in list mode. The cardiac cycle was divided into eight phases, the end-diastolic phase encompassing the QRS complex, and the end-systolic phase the T wave. Both phase- and non-phase-synchronized tomograms based on the same list mode data were reconstructed iteratively. Phase-synchronized and non-synchronized images were compared. Patients were divided into two groups depending on whether or not coronary artery disease had been definitely diagnosed prior to SPET imaging. The numbers of patients in both groups demonstrating defects visible on the phase-synchronized but not on the non-synchronized images were compared. It was found that both postexercise and redistribution phase tomograms were suited for interpretation. The changes from end-diastolic to end-systolic images allowed a comparative assessment of regional wall motility and tracer uptake. End-diastolic tomograms provided the best definition of defects. Additional defects not apparent on non-synchronized images were visible in 40 patients, six of whom did not show any defect on the non-synchronized images. Of 42 patients in whom coronary artery disease had been definitely diagnosed, 19 had additional defects not visible on the non-synchronized images, in comparison to 21 of 28 in whom coronary artery disease was suspected (P < 0.02; chi 2). It is concluded that cardiac phase-synchronized 201T1 SPET of the myocardium was made feasible by list mode data acquisition and iterative reconstruction. The additional findings on the phase-synchronized tomograms, not visible on the non-synchronized ones, represented genuine defects. Cardiac phase-synchronized 201T1 SPET is advantageous in allowing simultaneous assessment of regional wall motion and tracer uptake, and in visualizing smaller defects.

Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction

USGS Publications Warehouse

Hubert, A.E.; Chao, T.T.

1985-01-01

A rock, soil, or stream-sediment sample is decomposed with hydrofluoric acid, aqua regia, and hydrobromic acid-bromine solution. Gold, thallium, indium and tellurium are separated and concentrated from the sample digest by a two-step MIBK extraction at two concentrations of hydrobromic add. Gold and thallium are first extracted from 0.1M hydrobromic acid medium, then indium and tellurium are extracted from 3M hydrobromic acid in the presence of ascorbic acid to eliminate iron interference. The elements are then determined by flame atomic-absorption spectrophotometry. The two-step solvent extraction can also be used in conjunction with electrothermal atomic-absorption methods to lower the detection limits for all four metals in geological materials. ?? 1985.

Attentional Bias for Exercise-Related Images

ERIC Educational Resources Information Center

Berry, Tanya R.; Spence, John C.; Stolp, Sean M.

2011-01-01

This research examined attentional bias toward exercise-related images using a visual probe task. It was hypothesized that more-active participants would display attentional bias toward the exercise-related images. The results showed that men displayed attentional bias for the exercise images. There was a significant interaction of activity level…

Usefulness of automatic QT dispersion measurement for detecting exercise-induced myocardial ischemia.

PubMed

Takase, Bonpei; Masaki, Nobuyuki; Hattori, Hidemi; Ishihara, Masayuki; Kurita, Akira

2009-06-01

The electrocardiographic index of QT dispersion (QTd) is related to the occurrence of arrhythmia. In patients with suspected or known coronary artery disease, QTd may be affected by exercise. We investigated whether QTd that is automatically calculated by a newly developed computer system could be used as a marker of exercise-induced myocardial ischemia. The design of this study was prospective and observational. Eighty-three consecutive patients were enrolled in this study. Their QTd was measured at rest and after 3 min of exercise during exercise-stress Thallium-201 scintigraphy and compared with conventional ST-segment changes. The patients were classified into 4 groups (normal group, redistribution group, fixed defect group, redistribution with fixed defect group) based on the result of single photon emission computed tomography. As statistical analysis, one-way ANOVA with post-hoc Scheffe's method, receiver-operating characteristics (ROC) and multiple logistic regression analysis were performed. At rest, QTd was significantly greater (p<0.05) in the fixed defect group (52+/-21 ms) and the redistribution with fixed defect group (53+/-20 ms) than in the normal group (32+/-14 ms) and the redistribution group (31+/-16 ms). However, QTd tended to increase after exercise in the redistribution group, while QTd tended to decrease in the normal group, the fixed defect group, and the redistribution with fixed defect group (QTd after exercise, normal group, 28+/-17 ms, redistribution group, 35+/-19 ms, fixed defect group, 43+/-25 ms, redistribution with fixed defect group, 49+/-27 ms). Exercise significantly increased QTcd (RR interval-corrected QT dispersion) in the redistribution group. The best cut-off values of QTd and QTcd obtained from ROC curves for exercise-induced myocardial ischemia were 41.6 ms and 40.4 ms, respectively (Qtd--AUC 0.68, 95%CI 0.53- 0.83 and QTcd--AUC 0.67, 95%CI 0.55-0.80). Using these values as cut-off ones, QTd, QTcd, and conventional ST-segment change had comparable sensitivities and specificities for detecting exercise-induced myocardial ischemia (sensitivity - 60%, 58% and 49%, respectively;specificity - 78%, 80% and 83%, respectively). In addition, multiple logistic regression analysis showed that QTd (OR=2.01, 95%CI 1.15-4.10, p<0.05), QTcd (OR=2.12, 95% CI 1.02-4.30, p<0.05) and ST-segment change (OR=1.89, 95%CI 1.03-3.40, p<0.05), were the significantly associated with exercise-induced myocardial ischemia. QT dispersion and/or QTcd after exercise could be a useful marker for exercise-induced myocardial ischemia in routine clinical practice.

Practical use of imaging technique for management of bone and soft tissue tumors.

PubMed

Miwa, Shinji; Otsuka, Takanobu

2017-05-01

Imaging modalities including radiography, computed tomography (CT), and magnetic resonance imaging (MRI) are necessary for the diagnosis of bone and soft tissue tumors. The history of imaging began with the discovery of X-rays in the 19th century. The development of CT, MRI, ultrasonography, and positron emission tomography (PET) have improved the management of bone and soft tissue tumors. X-ray imaging and CT scans enable the evaluation of bone destruction, periosteal reaction, sclerotic changes in lesions, condition of cortical bone, and ossification. MRI enables the assessment of tissue characteristics, tumor extent, and the reactive areas. Functional imaging modalities including 201 thallium ( 201 Tl) scintigraphy can be used to differentiate benign lesions from malignant lesions and to assess chemotherapeutic effects. Real-time assessment of soft tissue tumors by ultrasonography enables accurate and safe performance of surgery and biopsy. This article describes useful imaging modalities and characteristic findings in the management of bone and soft tissue tumors. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Thallium myocardial perfusion scans for the assessment of right ventricular hypertrophy in patients with cystic fibrosis. A comparison with other noninvasive techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Newth, C.J.; Corey, M.L.; Fowler, R.S.

1981-01-01

The incidence of right ventricular hypertrophy in 32 patients with cystic fibrosis was studied using thallium 201 (TI-201) myocardial perfusion scans, and compared with other noninvasive techniques including electrocardiography, vectorcardiography, and M-mode echocardiography. The patients (mean age, 17.3 yr; range, 7 to 33) had a wide range of clinical and pulmonary abnormalities (mean Shwachman-Kulczycki score, 66.6). In the total study group, TI-201 scans, like the vectorcardiograms and the M-mode echocardiograms, gave a surprisingly high proportion of positive predictions for right ventricular hypertrophy (RVH) (44%). The correlations with all other noninvasive methods were uniformly poor, so caution must be exercised inmore » using this technique to predict early RVH in order to follow the natural history of cor pulmonale in cystic fibrosis. At the time of the study, 6 patients had clinical evidence of right ventricular failure, and in this disease setting must have had RVH. In 3 patients, RVH was confirmed at autopsy, and it was successfully predicted by TI-201 scans in 5 of the 6 patients. The false negative scan may have been due to regional myocardial ischemia secondary to severe right ventricular failure. In contrast, the vectorcardiogram, using Fowler's new criteria, made a successful prediction of RVH in all 6 patients, and the electro cardiogram in only 3. Although the M-mode echocardiogram was abnormal in all patients, it would have predicted RVH (with increased right ventricular anterior wall thickness) in only 1 patient. We concluded that TI-201 myocardial perfusion cans are good at confirming RVH in cases with established right ventricular failure, but have no advantage over vectorcardiographic assessments, which are logistically easier to perform and carry no radiation risks.« less

Two chamber reaction furnace

DOEpatents

Blaugher, Richard D.

1998-05-05

A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

Vertical two chamber reaction furnace

DOEpatents

Blaugher, Richard D.

1999-03-16

A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

Two chamber reaction furnace

DOEpatents

Blaugher, R.D.

1998-05-05

A vertical two chamber reaction furnace is described. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 C and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

Vertical two chamber reaction furnace

DOEpatents

Blaugher, R.D.

1999-03-16

A vertical two chamber reaction furnace is disclosed. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

Cardiac risk stratification in renal transplantation using a form of artificial intelligence.

PubMed

Heston, T F; Norman, D J; Barry, J M; Bennett, W M; Wilson, R A

1997-02-15

The purpose of this study was to determine if an expert network, a form of artificial intelligence, could effectively stratify cardiac risk in candidates for renal transplant. Input into the expert network consisted of clinical risk factors and thallium-201 stress test data. Clinical risk factor screening alone identified 95 of 189 patients as high risk. These 95 patients underwent thallium-201 stress testing, and 53 had either reversible or fixed defects. The other 42 patients were classified as low risk. This algorithm made up the "expert system," and during the 4-year follow-up period had a sensitivity of 82%, specificity of 77%, and accuracy of 78%. An artificial neural network was added to the expert system, creating an expert network. Input into the neural network consisted of both clinical variables and thallium-201 stress test data. There were 5 hidden nodes and the output (end point) was cardiac death. The expert network increased the specificity of the expert system alone from 77% to 90% (p < 0.001), the accuracy from 78% to 89% (p < 0.005), and maintained the overall sensitivity at 88%. An expert network based on clinical risk factor screening and thallium-201 stress testing had an accuracy of 89% in predicting the 4-year cardiac mortality among 189 renal transplant candidates.

Effects of image-based and text-based active learning exercises on student examination performance in a musculoskeletal anatomy course.

PubMed

Gross, M Melissa; Wright, Mary C; Anderson, Olivia S

2017-09-01

Research on the benefits of visual learning has relied primarily on lecture-based pedagogy, but the potential benefits of combining active learning strategies with visual and verbal materials on learning anatomy has not yet been explored. In this study, the differential effects of text-based and image-based active learning exercises on examination performance were investigated in a functional anatomy course. Each class session was punctuated with an average of 12 text-based and image-based active learning exercises. Participation data from 231 students were compared with their examination performance on 262 questions associated with the in-class exercises. Students also rated the helpfulness and difficulty of the in-class exercises on a survey. Participation in the active learning exercises was positively correlated with examination performance (r = 0.63, P < 0.001). When controlling for other key demographics (gender, underrepresented minority status) and prior grade point average, participation in the image-based exercises was significantly correlated with performance on examination questions associated with image-based exercises (P < 0.001) and text-based exercises (P < 0.01), while participation in text-based exercises was not. Additionally, students reported that the active learning exercises were helpful for seeing images of key ideas (94%) and clarifying key course concepts (80%), and that the image-based exercises were significantly less demanding, less hard and required less effort than text-based exercises (P < 0.05). The findings confirm the positive effect of using images and active learning strategies on student learning, and suggest that integrating them may be especially beneficial for learning anatomy. Anat Sci Educ 10: 444-455. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.

Enhanced Born Charge and Proximity to Ferroelectricity in Thallium Halides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du, Mao-Hua; Singh, David J

2010-01-01

Electronic structure and lattice dynamics calculations on thallium halides show that the Born effective charges in these compounds are more than twice larger than the nominal ionic charges. This is a result of cross-band-gap hybridization between Tl-p and halogen-p states. The large Born charges cause giant splitting between longitudinal and transverse optic phonon modes, bringing the lattice close to ferroelectric instability. Our calculations indeed show spontaneous lattice polarization upon lattice expansion starting at 2%. It is remarkable that the apparently ionic thallium halides with a simple cubic CsCl structure and large differences in electronegativity between cations and anions can bemore » very close to ferroelectricity. This can lead to effective screening of defects and impurities that would otherwise be strong carrier traps and may therefore contribute to the relatively good carrier transport properties in TlBr radiation detectors.« less

Enhanced Born charge and proximity to ferroelectricity in thallium halides

NASA Astrophysics Data System (ADS)

Du, Mao-Hua; Singh, David J.

2010-04-01

Electronic-structure and lattice-dynamics calculations on thallium halides show that the Born effective charges in these compounds are more than twice larger than the nominal ionic charges. This is a result of cross-band-gap hybridization between Tlp and halogen- p states. The large Born charges cause giant splitting between longitudinal and transverse-optic phonon modes, bringing the lattice close to ferroelectric instability. Our calculations indeed show that cubic TlBr develops ferroelectric instabilities upon lattice expansion starting at 2%. It is remarkable that the apparently ionic thallium halides with a simple cubic CsCl structure and large differences in electronegativity between cations and anions can be very close to ferroelectricity. This can lead to effective screening of defects and impurities that would otherwise be strong carrier traps and may therefore contribute to the relatively good carrier transport properties in TlBr radiation detectors.

Myocardial contusion in patients with blunt chest trauma as evaluated by thallium 201 myocardial scintigraphy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bodin, L.; Rouby, J.J.; Viars, P.

1988-07-01

Fifty five patients suffering from blunt chest trauma were studied to assess the diagnosis of myocardial contusion using thallium 201 myocardial scintigraphy. Thirty-eight patients had consistent scintigraphic defects and were considered to have a myocardial contusion. All patients with scintigraphic defects had paroxysmal arrhythmias and/or ECG abnormalities. Of 38 patients, 32 had localized ST-T segment abnormalities; 29, ST-T segment abnormalities suggesting involvement of the same cardiac area as scintigraphic defects; 21, echocardiographic abnormalities. Sixteen patients had segmental hypokinesia involving the same cardiac area as the scintigraphic defects. Fifteen patients had clinical signs suggestive of myocardial contusion and scintigraphic defects. Almostmore » 70 percent of patients with blunt chest trauma had scintigraphic defects related to areas of myocardial contusion. When thallium 201 myocardial scintigraphy directly showed myocardial lesion, two-dimensional echocardiography and standard ECG detected related functional consequences of cardiac trauma.« less

Effects of thallium(I) and thallium(III) on liposome membrane physical properties.

PubMed

Villaverde, Marcela S; Verstraeten, Sandra V

2003-09-15

The hypothesis that thallium (Tl) interaction with membrane phospholipids could result in the alteration of membrane physical properties was investigated. Working with liposomes composed of brain phosphatidylcholine and phosphatidylserine, we found that Tl(+), Tl(3+), and Tl(OH)(3) (0.5-25 microM): (a) increased membrane surface potential, (b) decreased the fluidity of the anionic regions of the membrane, in association with an increased fluidity in the cationic regions, and (c) promoted the rearrangement of lipids through lateral phase separation. The magnitude of these effects followed the order Tl(3+), Tl(OH)(3)>Tl(+). In addition, Tl(3+) also decreased the hydration of phospholipid polar headgroups and induced membrane permeabilization. The present results show that Tl interacts with membranes inducing major alterations in the rheology of the bilayer, which could be partially responsible for the neurotoxic effects of this metal.

Detection of right ventricular pressure overloading by thallium-201 myocardial scintigraphy. Results in 57 patients with chronic respiratory diseases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weitzenblum, E.; Moyses, B.; Dickele, M.C.

1984-02-01

The diagnostic value of thallium 201 (/sup 201/Tl) myocardial imaging was studied in 57 patients with chronic respiratory diseases, most with COPD (n . 46), by comparing the results to hemodynamic findings. In healthy subjects, the right ventricle (RV) is not visualized; therefore, any recorded activity of the RV was considered as indicating RV hypertrophy due to RV pressure overloading (RVPO). RV activity was graded from 0 (no activity) to 3 (activity greater than or equal to that of the left ventricle). Patients were divided into three groups according to the level of the pulmonary artery mean pressure (PPA): PPAmore » less than or equal to 20 mm Hg (no pulmonary arterial hypertension (PAH) ) . group 1, n . 20; PPA ranging from 21 to 30 mm Hg (mild to moderate PAH) . group 2, n . 20; PPA greater than 30 mm Hg (marked PAH) . group 3, n . 17. RV was visualized in 14 patients in group 3 (82 percent) and in 13 patients in group 2 (65 percent). For all patients with PAH (2 + 3) the sensitivity of /sup 201/Tl imaging for the diagnosis of RVPO was of 73 percent, higher than that of ECG and echocardiography (both 51 percent). The sensitivity of /sup 201/Tl, even if moderate (65 percent) was better than that of ECG (30 percent) or echo (40 percent) in patients with mild-to-moderate PAH (group 2). A high RV activity (grade 3) was observed in only three patients. The specificity of this method (obtained from results in group 1) was of 80 percent vs 89 percent for echo and 100 percent for ECG. These results suggest that 201Tl myocardial imaging is a rather sensitive method and could be of interest for the noninvasive diagnosis of RVPO in COPD patients.« less

Optimal reproducibility of gated sestamibi and thallium myocardial perfusion study left ventricular ejection fractions obtained on a solid-state CZT cardiac camera requires operator input.

PubMed

Cherk, Martin H; Ky, Jason; Yap, Kenneth S K; Campbell, Patrina; McGrath, Catherine; Bailey, Michael; Kalff, Victor

2012-08-01

To evaluate the reproducibility of serial re-acquisitions of gated Tl-201 and Tc-99m sestamibi left ventricular ejection fraction (LVEF) measurements obtained on a new generation solid-state cardiac camera system during myocardial perfusion imaging and the importance of manual operator optimization of left ventricular wall tracking. Resting blinded automated (auto) and manual operator optimized (opt) LVEF measurements were measured using ECT toolbox (ECT) and Cedars-Sinai QGS software in two separate cohorts of 55 Tc-99m sestamibi (MIBI) and 50 thallium (Tl-201) myocardial perfusion studies (MPS) acquired in both supine and prone positions on a cadmium zinc telluride (CZT) solid-state camera system. Resting supine and prone automated LVEF measurements were similarly obtained in a further separate cohort of 52 gated cardiac blood pool scans (GCBPS) for validation of methodology and comparison. Appropriate use of Bland-Altman, chi-squared and Levene's equality of variance tests was used to analyse the resultant data comparisons. For all radiotracer and software combinations, manual checking and optimization of valve planes (+/- centre radius with ECT software) resulted in significant improvement in MPS LVEF reproducibility that approached that of planar GCBPS. No difference was demonstrated between optimized MIBI/Tl-201 QGS and planar GCBPS LVEF reproducibility (P = .17 and P = .48, respectively). ECT required significantly more manual optimization compared to QGS software in both supine and prone positions independent of radiotracer used (P < .02). Reproducibility of gated sestamibi and Tl-201 LVEF measurements obtained during myocardial perfusion imaging with ECT toolbox or QGS software packages using a new generation solid-state cardiac camera with improved image quality approaches that of planar GCBPS however requires visual quality control and operator optimization of left ventricular wall tracking for best results. Using this superior cardiac technology, Tl-201 reproducibility also appears at least equivalent to sestamibi for measuring LVEF.

[The 18F-FDG myocardial metabolic imaging in twenty seven pilots with regular aerobic training].

PubMed

Fang, Ting-Zheng; Zhu, Jia-Rui; Chuan, Ling; Zhao, Wen-Rui; Xu, Gen-Xiang; Yang, Min-Fu; He, Zuo-Xiang

2009-02-01

To evaluate the characteristics of myocardial (18)F-FDG imaging in pilots with regular aerobic exercise training. Twenty seven healthy male pilots with regular aerobic exercise training were included in this study. The subjects were divided into fasting (n = 17) or non-fasting group (n = 10). Fluorine-18-labeled deoxyglucose and Tc-99m-sestamibi dual-nuclide myocardial imaging were obtained at rest and at target heart rate during bicycle ergometer test. The exercise and rest myocardial perfusion imaging were analyzed for myocardial ischemia presence. The myocardial metabolism imaging was analyzed with the visual semi-quantitative analyses model of seventeen segments. The secondary-extreme heart rate (195-age) was achieved in all subjects. There was no myocardial ischemia in all perfusion imaging. In the visual qualitative analyses, four myocardial metabolism imaging failed in the fasting group while one failed in the non-fasting group (P > 0.05). In the visual semi-quantitative analyses, myocardial metabolism imaging scores at rest or exercise in all segments were similar between two groups (P > 0.05). In the fasting group, the myocardial metabolism imaging scores during exercise were significantly higher than those at rest in 6 segments (P < 0.05). In the non-fasting group, the scores of 3 exercise myocardial metabolism imaging were significantly higher than those at rest (P < 0.05). Satisfactory high-quality myocardial metabolism imaging could be obtained at fasting and exercise situations in subjects with regular aerobic exercise.

Present assessment of myocardial viability by nuclear imaging.

PubMed

Saha, G B; MacIntyre, W J; Brunken, R C; Go, R T; Raja, S; Wong, C O; Chen, E Q

1996-10-01

Prospective delineation of viable from nonviable myocardium in patients with coronary artery disease in an important factor in deciding whether a patient should be revascularized or treated medically. Two common techniques--single-photon emission computed tomography (SPECT) and positron-emission computed tomography (PET)--are used in nuclear medicine using various radiopharmaceuticals for the detection of myocardial viability in patients. Thallium-201 (201Tl) and technetium-99m (99mTc)-sestamibi are the common radiopharmaceuticals used in different protocols using SPECT, whereas fluoride-18 (18F)-fluorodeoxyglucose (FDG) and rubidium-82 (82Rb) are most widely used in PET. The SPECT protocols involve stress/redistribution, stress/redistribution/reinjection, and rest/redistribution imaging techniques. Many studies have compared the results of 201Tl and (99mTc)-sestamibi SPECT with those of FDG PET; in some studies, concordant results have been found between delayed thallium and FDG results, indicating that 201Tl, although considered a perfusion agent, shows myocardial viability. Discordant results in a number of studies have been found between sestamibi and FDG, suggesting that the efficacy of sestamibi as a viability marker has yet to be established. Radiolabeled fatty acids such as iodine-123 (123I)-para-iodophenylpentadecanoic acid and carbon-11 (11C)-palmitic acid have been used for the assessment of myocardial viability with limited success. 11C-labeled acetate is a good marker of oxidative metabolism in the heart and has been used to predict the reversibility of wall motion abnormalities. (18F)-FDG is considered the marker of choice for myocardial viability, although variable results are obtained under different physiological conditions. Detection of myocardial viability can be greatly improved by developing new equipment and radiopharmaceuticals of better quality.

Titanium Diboride Electrodeposited Coatings

DTIC Science & Technology

1977-06-01

4 Ti02. This material was deposited in the form of a porous mass or loose particles which must be leached in water and acid to remove adherent...poudres metallique par electrolyse ignee. Revue de Metallurgie, v. 45, 1948, p. 49-59. 7. POWELL, C. F. Borides in High Temperature Materials and... water solution of thallium formate-thallium malonate 50-50 mole percent mixture with a density ranging from about 5 g/cm^ at the bottom to about 2 g/cm

Engineering and design properties of thallium-doped sodium iodide and selected properties of sodium-doped cesium iodide

NASA Technical Reports Server (NTRS)

Forrest, K.; Haehner, C.; Heslin, T.; Magida, M.; Uber, J.; Freiman, S.; Hicho, G.; Polvani, R.

1984-01-01

Mechanical and thermal properties, not available in the literature but necessary to structural design, using thallium doped sodium iodide and sodium doped cesium iodide were determined to be coefficient of linear thermal expansion, thermal conductivity, thermal shock resistance, heat capacity, elastic constants, ultimate strengths, creep, hardness, susceptibility to subcritical crack growth, and ingot variation of strength. These properties were measured for single and polycrystalline materials at room temperature.

Remedial Investigation Addendum Report Data Item A009. Volume 4: Appendices I-Z

DTIC Science & Technology

1993-12-01

Impatien~s capensis FACW Yellow Iris Iris pseudoacorus OBL Blueflag Iris Iris versicolor OBL 1 21 I NEW ENGLAND ENVIRONMENTAL, INC. Duckweed Lemna spp...small mammal community in the food web model. American woodcock (Scolopax minor ). This small bird is often j found in forested wetlands and forages...34Drinking Water and Health" Safe Drinking Water Committee, Washington, D.C. Thallium Thallium is a naturally occurring soft metal that is a minor

Prognostic significance of normal quantitative planar thallium-201 stress scintigraphy in patients with chest pain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wackers, F.J.; Russo, D.J.; Russo, D.

The prognostic significance of normal quantitative planar thallium-201 stress scintigraphy was evaluated in patients with a chest pain syndrome. The prevalence of cardiac events during follow-up was related to the pretest (that is, before stress scintigraphy) likelihood of coronary artery disease determined on the basis of symptoms, age, sex and stress electrocardiography. In a consecutive series of 344 patients who had adequate thallium-201 stress scintigrams, 95 had unequivocally normal studies by quantitative analysis. The pretest likelihood of coronary artery disease in the 95 patients had a bimodal distribution. During a mean follow-up period of 22 +/- 3 months, no patientmore » died. Three patients (3%) had a cardiac event: two of these patients (pretest likelihood of coronary artery disease 54 and 94%) had a nonfatal myocardial infarction 8 and 22 months, respectively, after stress scintigraphy, and one patient (pretest likelihood 98%) underwent percutaneous transluminal coronary angioplasty 16 months after stress scintigraphy for persisting anginal complaints. Three patients were lost to follow-up; all three had a low pretest likelihood of coronary artery disease. It is concluded that patients with chest pain and normal findings on quantitative thallium-201 scintigraphy have an excellent prognosis. Cardiac events are rare (infarction rate 1% per year) and occur in patients with a moderate to high pretest likelihood of coronary artery disease.« less

Flotation separation and electrothermal atomic absorption spectrometric determination of thallium in wastewater samples.

PubMed

Hosseini, Mohammad Saeid; Chamsaz, Mahmoud; Raissi, Heidar; Naseri, Yousef

2006-01-01

The proposed method is a simple process for the determination of trace amount of thallium(I) in the environmental wastewater samples by electrothermal atomic absorption spectrometry. The wastewater samples were obtained from the environment of a cement plant and subjected to a simple treatment, such as adjusting pH and masking the interfering ions, to prepare for the flotation process in which the thallium(I) content was floated as an ion-association complex using iodide and Rhodamine B at the interface of aqueous/cyclohexane layers. The floated layer was then separated and dissolved in 2 ml of a solution, which was 1% to H2SO4 and 50% to methanol, respectively. Aliquots of 10-microl of this solution were subjected to the graphite furnace to determine the thallium(I) content. The flotation process can be carried in a weak acidic medium in which the interfering effects owing to certain metal ions were eliminated by masking them as neutral citrate chelates. The dynamic range for the determination was found to be 1.0 x 10(-8) - 1.0 x 10(-7) mol l(-1). The RSD was 3.2% and the DL was 2.5 x 10(-9) mol l(-1) (calculated as 3SD of the blank). The reliability of the method is demonstrated by the analysis of a synthetic wastewater in which the recovery was found to be 94%.

Behavior of cesium and thallium cations inside a calixarene cavity as probed by nuclear spin relaxation. Evidence of cation-pi interactions in water.

PubMed

Cuc, Diana; Bouguet-Bonnet, Sabine; Morel-Desrosiers, Nicole; Morel, Jean-Pierre; Mutzenhardt, Pierre; Canet, Daniel

2009-08-06

We have studied the complexes formed between the p-sulfonatocalix[4]arene and cesium or thallium metal cation, first by carbon-13 longitudinal relaxation of the calixarene molecule at two values of the magnetic field B(0). From the longitudinal relaxation times of an aromatic carbon directly bonded to a proton, thus subjected essentially to the dipolar interaction with that proton, we could obtain the correlation time describing the reorientation of the CH bond. The rest of this study has demonstrated that it is also the correlation time describing the tumbling of the whole calixarene assembly. From three non-proton-bearing carbons of the aromatic cycles (thus subjected to the chemical shift anisotropy and dipolar mechanisms), we have been able to determine the variation of the chemical shift anisotropy when going from the free to the complex form of the calixarene. These variations not only provide the location of the cation inside the calixarene cavity but also constitute a direct experimental proof of the cation-pi interactions. These results are complemented by cesium and thallium relaxation measurements performed again at two values of the magnetic field B(0). An estimation of the mean distance between the cation and the calixarene protons could be obtained. These measurements have also revealed an important chemical shift anisotropy of thallium upon complexation.

The importance of the function of exercise in the relationship between obligatory exercise and eating and body image concerns.

PubMed

De Young, Kyle P; Anderson, Drew A

2010-01-01

This study tested whether exercising in response to negative affect moderates the association between obligatory exercise and eating and body image psychopathology. Participants (n=226) completed the Eating Disorders Examination-Questionnaire (EDE-Q), Obligatory Exercise Questionnaire (OEQ), and a question assessing whether they ever exercise in response to negative affect. In total, 132 (58.4%) participants endorsed exercising in response to negative affect. Multiple regression analyses revealed significant main effects of negative affect motivated exercise, OEQ total scores, and gender on all four EDE-Q subscales and significant interactions of negative affect motivated exercise and OEQ scores on the Eating Concern, Shape Concern, and Weight Concern scales but not the Restraint scale of the EDE-Q. Obligatory exercisers may not demonstrate elevated eating and body image concerns in the absence of negative affect motivated exercise, providing further support of the importance of the function of exercise.

Thermophysical Properties of Matter - The TPRC Data Series. Volume 4. Specific Heat - Metallic Elements and Alloys

DTIC Science & Technology

1971-01-01

alloys— sodium — sodium alloya— solder—carbon ateels—chromium steels—silicon steels—tantalum—tantalum alloys—terbium—thallium—thallium alloys—thorium...Praseodymium 45 Rhenium 46 Rhodium 47 Rubidium 48 Ruthenium 4» Samarium 50 Scandium 51 Selenium 52 Silicon 5:i Silver 54 Sodium 55 Strontium 56...Potassium ♦ Sodium 111 Sodium * Potassium 112 Tantalum ♦ Tungsten 113 Thallium + Lead, PbTl| 114 Tin ♦ Bismuth 115 Tin ♦ Indium 116 Tin+ Lead 117

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oshima, M.; Port, S.C.; Ray, G.

Forty-two patients (pts) with 1VD(greater than or equal to 70% stenosis and no prior infarction) undergoing PTCA provide a model to study the efficacy with which non-invasive tests can a) detect stress induced ischemia and b) reflect the reduction in stress induced ischemia expected from arteriographically successful PTCA. The diseased coronary was the right in 12, the circumflex in 3 and the LAD in 27 pts. Pre- and post- PTCA paired data were available from treadmill (ETT), planar thallium (Qual-T1), 7 pinhole tomography and 1st pass radionuclide angiograms (RNA) in 29, 26, 31 and 25 pts. After tomographic images weremore » digitized and analyzed by a computer, the intensity (=area/range, a numerical index of the severity of a defect) served as a quantitative T1 (Quant-T1). Criteria for ischemia were: significant ST change on ETT, unequivocal stress defects on Qual-T1, Quant-T1 intensity greater than or equal to 2.0, and exercise ejection fraction (Ex EF) greater than or equal to 0.55 or a new wall motion abnormality on Ex RNA. Ex EF was .61 +- .13 pre- and .63 +- .10 post-PTCA (p=NS). Quant-T1 intensity was 9.5 +- 7.1 pre- and 4.0 +- 5.5 post-PTCA (p=.0003). T1 testing was the most sensitive for detecting ischemia pre-PTCA. However, given an ischemic response pre-PTCA, the RNA showed the greatest trend toward normalization post-PTCA. If one test must be chosen Quant-T1 seems most appropriate in the evaluation of pre- and post- PTCA pts with 1VD.« less

"Strong beats skinny every time": Disordered eating and compulsive exercise in women who post fitspiration on Instagram.

PubMed

Holland, Grace; Tiggemann, Marika

2017-01-01

Fitspiration is a recent Internet trend designed to motivate people to eat healthily and to exercise. The aim of the study was to investigate disordered eating and exercise in women who post fitspiration on Instagram. Participants were 101 women who post fitspiration images on Instagram and a comparison group of 102 women who post travel images. Both groups completed measures of disordered eating and compulsive exercise. Women who post fitspiration images scored significantly higher on drive for thinness, bulimia, drive for muscularity, and compulsive exercise. Almost a fifth (17.5%) of these women were at risk for diagnosis of a clinical eating disorder, compared to 4.3% of the travel group. Compulsive exercise was related to disordered eating in both groups, but the relationship was significantly stronger for women who post fitspiration images. For some women, posting fitspiration images on Instagram may signify maladaptive eating and exercise behaviors. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2017; 50:76-79). © 2016 Wiley Periodicals, Inc.

Perceptions of masculinity and body image in men with prostate cancer: the role of exercise.

PubMed

Langelier, David Michael; Cormie, Prue; Bridel, William; Grant, Christopher; Albinati, Natalia; Shank, Jena; Daun, Julia Teresa; Fung, Tak S; Davey, Colin; Culos-Reed, S Nicole

2018-04-13

The goal of this study was to explore the association between levels of exercise and patterns of masculinity, body image, and quality of life in men undergoing diverse treatment protocols for prostate cancer. Fifty men with prostate cancer (aged 42-86) completed self-report measures. Self-reported measures included the following: the Godin Leisure Time Exercise Questionnaire (GLTEQ), Masculine Self-esteem Scale (MSES), Personal Attributes Questionnaire (PAQ), Body Image Scale (BIS), and the Functional Assessment of Cancer Therapy-Prostate (FACT-P). Masculinity, body image, and quality of life scores were compared between men obtaining recommended levels of exercise (aerobic or resistance) and those not obtaining recommended level of exercise. Secondary outcomes included the association between masculinity, body image, and quality of life scores as they relate to exercise levels. There were significantly higher scores of masculinity (p < 0.01), physical well-being (p < 0.05), prostate cancer specific well-being (p < 0.05), and overall quality of life (p < 0.05) in those obtaining at least 150 min of moderate to vigorous aerobic exercise. In the 48% of men who had never received androgen deprivation therapy, significantly higher levels of masculinity, body image, and quality of life were observed in those meeting aerobic guidelines. Whether treatment includes androgen deprivation or not, men who participate in higher levels of aerobic exercises report higher levels of masculinity, improved body image, and quality of life than those who are inactive. Future longitudinal research is required evaluating exercise level and its effect on masculinity and body image.

Cathode Degradation in Thallium Bromide Devices

NASA Astrophysics Data System (ADS)

Datta, Amlan; Motakef, Shariar

2015-06-01

Thallium bromide (TlBr) is a wide bandgap, compound semiconductor with high gamma-ray stopping power and promising physical properties. However, performance degradation and the eventual irreversible failure of TlBr devices can occur rapidly at room temperature, due to “polarization”, caused by the electromigration of Tl+ and Br- ions to the electrical contacts across the device. Using the Accelerated Device Degradation (ADD) experiment, the degradation phenomena in TlBr devices have been visualized and recorded. This paper focuses on “ageing” of the device cathode at various temperatures. ADD is a fast and reliable direct characterization technique that can be used to identify the effects of various growth and post-growth process modifications on device degradation. Using this technique we have identified cathode degradation with the migration of Br- ions and an associated generation and growth of Thallium-rich fractal “ferns” from the cathode. Its effect on the radiation response of the device has also been discussed in this paper. The chemical changes in the cathode were characterized using Energy-dispersive X-ray spectroscopy.

Arsenic, Antimony, Chromium, and Thallium Speciation in Water and Sediment Samples with the LC-ICP-MS Technique

PubMed Central

Jabłońska-Czapla, Magdalena

2015-01-01

Chemical speciation is a very important subject in the environmental protection, toxicology, and chemical analytics due to the fact that toxicity, availability, and reactivity of trace elements depend on the chemical forms in which these elements occur. Research on low analyte levels, particularly in complex matrix samples, requires more and more advanced and sophisticated analytical methods and techniques. The latest trends in this field concern the so-called hyphenated techniques. Arsenic, antimony, chromium, and (underestimated) thallium attract the closest attention of toxicologists and analysts. The properties of those elements depend on the oxidation state in which they occur. The aim of the following paper is to answer the question why the speciation analytics is so important. The paper also provides numerous examples of the hyphenated technique usage (e.g., the LC-ICP-MS application in the speciation analysis of chromium, antimony, arsenic, or thallium in water and bottom sediment samples). An important issue addressed is the preparation of environmental samples for speciation analysis. PMID:25873962

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karabourniotis, D.; Couris, S.; Damelincourt, J.J.

The partial pressure of thallium in high-pressure Hg-TlI discharges with different mercury, thallium, and electron pressures has been measured by using the optically thin line Tl 655 nm and the self-reversed line Tl 535 nm. The partial pressure of the arc axis has been measured from the line Tl 655nm. The effective partial pressure has been measured from the self-reversed line Tl 535 nm on the basis of the multiparameter method, and it has been calculated from the known axis pressure of thallium and the calculation of its radial variation by taking into account the chemical reactions. The experimental resultsmore » confirm the dispersion character of the blue wing of the line Tl 535 nm. The systematic difference obtained between the measured and calculated effective pressure, particularly at the moment of minimum electron density, may be interpreted by deviations from the local thermodynamic equilibrium (LTE) caused by overpopulation of the upper level of the line Tl 535 nm.« less

Do thallium myocardial perfusion scan abnormalities predict survival in sarcoid patients without cardiac symptoms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kinney, E.L.; Caldwell, J.W.

1990-07-01

Whereas the total mortality rate for sarcoidosis is 0.2 per 100,000, the prognosis, when the heart is involved, is very much worse. The authors used the difference in mortality rate to infer whether thallium 201 myocardial perfusion scan abnormalities correspond to myocardial sarcoid by making the simplifying assumption that if they do, then patients with abnormal scans will be found to have a death rate similar to patients with sarcoid heart disease. The authors therefore analyzed complete survival data on 52 sarcoid patients without cardiac symptoms an average of eighty-nine months after they had been scanned as part of amore » protocol. By use of survival analysis (the Cox proportional hazards model), the only variable that was significantly associated with survival was age. The patients' scan pattern, treatment status, gender, and race were not significantly related to survival. The authors conclude that thallium myocardial perfusion scans cannot reliably be used to diagnose sarcoid heart disease in sarcoid patients without cardiac symptoms.« less

Short infrared (IR) laser pulses can induce nanoporation

NASA Astrophysics Data System (ADS)

Roth, Caleb C.; Barnes, Ronald A.; Ibey, Bennett L.; Glickman, Randolph D.; Beier, Hope T.

2016-03-01

Short infrared (IR) laser pulses on the order of hundreds of microseconds to single milliseconds with typical wavelengths of 1800-2100 nm, have shown the capability to reversibly stimulate action potentials (AP) in neuronal cells. While the IR stimulation technique has proven successful for several applications, the exact mechanism(s) underlying the AP generation has remained elusive. To better understand how IR pulses cause AP stimulation, we determined the threshold for the formation of nanopores in the plasma membrane. Using a surrogate calcium ion, thallium, which is roughly the same shape and charge, but lacks the biological functionality of calcium, we recorded the flow of thallium ions into an exposed cell in the presence of a battery of channel antagonists. The entry of thallium into the cell indicated that the ions entered via nanopores. The data presented here demonstrate a basic understanding of the fundamental effects of IR stimulation and speculates that nanopores, formed in response to the IR exposure, play an upstream role in the generation of AP.

Observation of the Forbidden Magnetic Dipole Transition 6{sup 2}P{sub ?} --> 7{sup 2}P{sub ?} in Atomic Thallium

DOE R&D Accomplishments Database

Chu, S.

1976-10-01

A measurement of the 6{sup 2}P{sub ?} --> 7{sup 2}P{sub ?} forbidden magnetic dipole matrix element in atomic thallium is described. A pulsed, linearly polarized dye laser tuned to the transition frequency is used to excite the thallium vapor from the 6{sup 2}P{sub ?} ground state to the 7{sup 2}P{sub ?} excited state. Interference between the magnetic dipole M1 amplitude and a static electric field induced E1 amplitude results in an atomic polarization of the 7{sup 2}P{sub ?} state, and the subsequent circular polarization of 535 nm fluorescence. The circular polarization is seen to be proportional to / as expected, and measured for several transitions between hyperfine levels of the 6{sup 2}P{sub ?} and 7{sup 2}P{sub ?} states. The result is = -(2.11 +- 0.30) x 10{sup -5} parallel bar e parallel bar dirac constant/2mc, in agreement with theory.

Planetary Exploration in the Classroom

NASA Astrophysics Data System (ADS)

Slivan, S. M.; Binzel, R. P.

1997-07-01

We have developed educational materials to seed a series of undergraduate level exercises on "Planetary Exploration in the Classroom." The goals of the series are to teach modern methods of planetary exploration and discovery to students having both science and non-science backgrounds. Using personal computers in a "hands-on" approach with images recorded by planetary spacecraft, students working through the exercises learn that modern scientific images are digital objects that can be examined and manipulated in quantitative detail. The initial exercises we've developed utilize NIH Image in conjunction with images from the Voyager spacecraft CDs. Current exercises are titled "Using 'NIH IMAGE' to View Voyager Images", "Resolving Surface Features on Io", "Discovery of Volcanoes on Io", and "Topography of Canyons on Ariel." We expect these exercises will be released during Fall 1997 and will be available via 'anonymous ftp'; detailed information about obtaining the exercises will be on the Web at "http://web.mit.edu/12s23/www/pec.html." This curriculum development was sponsored by NSF Grant DUE-9455329.

Examination of a sociocultural model of excessive exercise among male and female adolescents.

PubMed

White, James; Halliwell, Emma

2010-06-01

There is substantial evidence that sociocultural pressures and body image disturbances can lead to disordered eating, yet few studies have examined their impact on excessive exercise. The study adapted a sociocultural model for disordered eating to predict excessive exercise using data from boys and girls in early adolescence (N=421). Perceived sociocultural pressures to lose weight and build muscle, body image disturbance and appearance investment were associated with a compulsive need to exercise. Adolescents' investment in appearance and body image disturbance fully mediated the relationship between sociocultural pressures and a compulsive need for exercise. There was no support for the meditational model in predicting adolescents' frequency or duration of exercise. Results support the sociocultural model as an explanatory model for excessive exercise, but suggest appearance investment and body image disturbance are important mediators of sociocultural pressures. 2010 Elsevier Ltd. All rights reserved.

Charge carrier transport properties in thallium bromide crystalls used as radiation detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olschner, F.; Toledo-Quinones, M.; Shah, K.S.

1990-06-01

Thallium bromide (TlBr) is an attractive material for use in radiation detectors because of its wide bandgap (2.68 eV) and very high atomic number. Usefulness as a semiconductor detector material, however, also requires good charge carrier transport properties in order to maximize the magnitude of the signal from the detector. The authors report on measurements of the two most important transport parameters; the mobility {mu} and the mean trapping time {tau} for electrons and holes in TlBr crystals prepared in the laboratory.

Influence of multi-depositions on the final properties of thermally evaporated TlBr films

NASA Astrophysics Data System (ADS)

Destefano, N.; Mulato, M.

2010-12-01

Thallium bromide is a promising candidate material for photodetectors in medical imaging systems. This work investigates the structural, optical and electrical properties of thermally evaporated TlBr films. The main fabrication parameter is the number of depositions. The use of sequential runs is aimed to increase the thickness of the films, as necessary, for technological applications. We deposited films using one-four runs, that led to maximum thickness of about 50 μm. Crystallographic and morphological changes were observed with varying deposition runs. Nevertheless, the optical gap and electrical resistivity in the dark remained constant at about 2.85 eV and 10 9 Ω cm, respectively. Thicker samples have a larger ratio of photo-to-dark signal under medical X-ray exposure, with a larger linear region as a function of applied voltage. The results are discussed aiming at future technological applications in medical imaging.

Positron Emission Tomography of the Heart

DOE R&D Accomplishments Database

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

1979-01-01

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

Equilibrium stable-isotope fractionation of thallium and mercury

NASA Astrophysics Data System (ADS)

Schauble, E. A.

2005-12-01

In this study first-principles quantum mechanical and empirical force-field models are used to estimate equilibrium mass-dependent isotopic fractionations among a variety of thallium and mercury compounds. High-precision MC-ICP-MS measurements have recently uncovered evidence of stable isotope fractionation for many elements, including 2-4‰ variability in the isotopic compositions of thallium[1] (atomic no. 81) and mercury[2] (atomic no. 80). The observed thallium- and mercury-isotope fractionations are remarkable, given that the magnitude of isotopic fractionation typically decreases as atomic number increases[3]. Stable isotope measurements could improve our understanding of geochemical and biogeochemical cycling of both elements, but little is known about the mechanisms driving these fractionations. A better understanding of the chemical processes controlling stable isotope compositions could help maximize the utility of these new geochemical tracers. Standard equilibrium stable isotope fractionation theory holds that the energy driving fractionation comes from isotopic effects on vibrational frequencies, which have generally not been measured. In the present study both quantum-mechanical and empirical force fields are used to estimate unknown frequencies. Results suggest that thallium and mercury fractionations of ≥ 0.5‰ are likely during the relevant redox reactions Tl+ ↔ Tl3+ and HgO ↔ Hg2+. Methyl-mercury and mercury-halide compounds like CH3HgCl will have ~ 1‰ higher 202Hg/198Hg than atomic vapor at room temperature. Fractionations between coexisting Hg2+ species appear to be much smaller, however. 205Tl/203Tl in Tl(H2O)_63+ is predicted to be ~0.5‰ higher than in coexisting Tl+-bearing substances. This result is in qualitative agreement with data from ferromanganese crusts [1], suggesting that Tl3+ in manganese-oxides will have higher 205Tl/203Tl than aqueous Tl+. Equilibrium fractionations for both elements are much smaller than the observed range of isotopic fractionations, however, which could point to a major role for kinetic-fractionation or Rayleigh-like distillation processes. Refs.: [1] Rehämper et al. (2002) EPSL 197:65. [2] Xie et al. (2005) J. Anal. Atomic Spectrom. 20:515. [3] Bigeleisen and Mayer (1947) J. Chem. Phys. 15:261.

Tracking Early Jurassic marine (de)oxygenation

NASA Astrophysics Data System (ADS)

Them, T. R., II; Caruthers, A. H.; Gill, B. C.; Gröcke, D. R.; Marroquín, S. M.; Owens, J. D.

2017-12-01

It has been suggested that the carbon cycle was perturbed during the Toarcian OAE (T-OAE) as observed in the carbon isotope record, and more recently other elemental cycles (e.g., Hg, Mo, Os, S). The most widely accepted hypothesis focuses on the emplacement of the Karoo-Ferrar large igneous province, outgassing of greenhouse gases, and subsequent feedbacks in the Earth system, which caused severe environmental change and biological turnover. Feedbacks to elevated atmospheric pCO2 include enhanced weathering rates, dissociation of methane clathrates, increased terrestrial methanogenesis, and widespread marine anoxia. The sequence of events related to the development and duration of marine anoxia are not well constrained for this time interval due to a lack of open-ocean geochemical records. In order to reconstruct the timing of marine deoxygenation during the Early Jurassic T-OAE, we have utilized thallium isotopes, a novel geochemical proxy from multiple anoxic basins in North America and Germany. Three sites representing a basin transect from the Western Canada Sedimentary Basin, and one site from the South German Basin, were chosen to reconstruct the thallium isotopic composition (ɛ205Tl) of the ocean. The ɛ205Tl composition of sediments deposited under anoxic and euxinic water columns records the global seawater ɛ205Tl composition, a function of the amount of manganese oxides that are precipitated. Increased geographic extent of marine anoxia will cause a decrease in manganese oxide precipitation and perturb the thallium system. Importantly, the inputs of thallium are nearly identical, thus changes in these fluxes cannot drive the observed perturbation. Our new Early Jurassic ɛ205Tl records suggest that the onset of marine deoxygenation occurred concurrently with Karoo-Ferrar magmatism in the late Pliensbachian and continued until after the T-OAE. These new data support a Karoo-Ferrar trigger of the T-OAE. However, thallium isotopes also suggest that widespread marine deoxygenation was prevalent before and after the carbon isotope-defined T-OAE, which suggests significant oxygen consumption through carbon remineralization pre- and post-OAE. Thus, the OAE actually represents the interval of minimum oceanic oxygen and maximum euxinia, which primes the system for maximum organic carbon burial.

Molecular association of normal alkanoic acids with their thallium(I) salts: a new homologous series of fatty acid metal soaps.

PubMed

Fernández-García, M; García, M V; Redondo, M I; Cheda, J A; Fernández-García, M; Westrum, E F; Fernández-Martín, F

1997-02-01

A new homologous series of thallium(I) hydrogen dialkanoates, fatty acid thallium soaps, from the dipropane up to the ditetradecane is reported for the first time. This association with 1:1 stoichiometry is the only one exhibited by the thallium derivatives. They have been prepared by solidification of molten mixtures with equimolar proportions of acid and corresponding neutral salt, through crystallization from an anhydrous ethanolic solution of the mixture has also been successful in getting pure compounds with largest chain lengths. Vibrational spectroscopies clearly characterize these crystalline compounds as very strong hydrogen bonding systems. Assignations of active modes in proton and carbon nuclear magnetic resonance spectrometry (NMR) (in ethanol) and infrared (IR) and Raman spectra (in solid state) are reported. According to X-ray diffraction (XRD) they have monomolecular lamellar structures with the acyl chains arranged up and down to the cation/H-bond network in a methyl-to-methyl fashion, and vertically oriented to the basal plane. The acyl chains present all-trans conformation and alternating configuration (perpendicular orthorhombic subcell), like the beta'-phases of other kinds of lipids. Lamellar thickness is reported for the six room-temperature crystalline members. The molecular compounds present polymorphism, one crystal/crystal transition at temperatures close to the peritectical melting. Phase transition thermodynamics are also given and discussed with respect to their acid and salt parents. Their incongruent melting involves nearly 90% of the total enthalpic increments of both constituents' melting processes, making these compounds potential thermal energy storage materials.

Growth Mechanism of Nanowires: Binary and Ternary Chalcogenides

NASA Technical Reports Server (NTRS)

Singh, N. B.; Coriell, S. R.; Su, Ching-Hua; Hopkins, R. H.; Arnold, B.; Choa, Fow-Sen; Cullum, Brian

2016-01-01

Semiconductor nanowires exhibit very exciting optical and electrical properties including high transparency and a several order of magnitude better photocurrent than thin film and bulk materials. We present here the mechanism of nanowire growth from the melt-liquid-vapor medium. We describe preliminary results of binary and ternary selenide materials in light of recent theories. Experiments were performed with lead selenide and thallium arsenic selenide systems which are multifunctional material and have been used for detectors, acousto-optical, nonlinear and radiation detection applications. We observed that small units of nanocubes and elongated nanoparticles arrange and rearrange at moderate melt undercooling to form the building block of a nanowire. Since we avoided the catalyst, we observed self-nucleation and uncontrolled growth of wires from different places. Growth of lead selenide nanowires was performed by physical vapor transport method and thallium arsenic selenide nanowire by vapor-liquid-solid (VLS) method. In some cases very long wires (>mm) are formed. To achieve this goal experiments were performed to create situation where nanowires grew on the surface of solid thallium arsenic selenide itself.

New SPECT and PET Radiopharmaceuticals for Imaging Cardiovascular Disease

PubMed Central

Sogbein, Oyebola O.; Pelletier-Galarneau, Matthieu; Schindler, Thomas H.; Wei, Lihui; Wells, R. Glenn; Ruddy, Terrence D.

2014-01-01

Nuclear cardiology has experienced exponential growth within the past four decades with converging capacity to diagnose and influence management of a variety of cardiovascular diseases. Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) with technetium-99m radiotracers or thallium-201 has dominated the field; however new hardware and software designs that optimize image quality with reduced radiation exposure are fuelling a resurgence of interest at the preclinical and clinical levels to expand beyond MPI. Other imaging modalities including positron emission tomography (PET) and magnetic resonance imaging (MRI) continue to emerge as powerful players with an expanded capacity to diagnose a variety of cardiac conditions. At the forefront of this resurgence is the development of novel target vectors based on an enhanced understanding of the underlying pathophysiological process in the subcellular domain. Molecular imaging with novel radiopharmaceuticals engineered to target a specific subcellular process has the capacity to improve diagnostic accuracy and deliver enhanced prognostic information to alter management. This paper, while not comprehensive, will review the recent advancements in radiotracer development for SPECT and PET MPI, autonomic dysfunction, apoptosis, atherosclerotic plaques, metabolism, and viability. The relevant radiochemistry and preclinical and clinical development in addition to molecular imaging with emerging modalities such as cardiac MRI and PET-MR will be discussed. PMID:24901002

Electrocrystallization and scanning probe microscopy of ceramic thin films and superlattices

NASA Astrophysics Data System (ADS)

Hung, Chen-Jen

This dissertation presents an investigation of the electrocrystallization and scanning probe microscopy of ceramic thin films and superlattices. All of the films were deposited from aqueous solution at room temperature with no subsequent heat treatment needed to effect crystallization. Thallium(III) oxide defect chemistry superlattices were electrodeposited by pulsing the applied overpotential during deposition. The defect chemistry of the oxide is dependent on the applied overpotential. High overpotentials favor oxygen vacancies, while low overpotentials favor cation interstitials. Nanometer-scale holes were formed in thin thallium(III) oxide films using the scanning tunneling microscope in humid ambient conditions. Both cathodic and anodic etching reactions were performed on this metal oxide surface. The hole formation was attributed to localized electrochemical etching reactions beneath the STM tip. The scanning tunneling microscope (STM) was also used to both induce local surface modifications and image cleaved Pb-Tl-O superlattices. A trench of 100 nm in width, 32 nm in depth, and over 1 μm in length was formed after sweeping a bias voltage of ±2.5 V for 1 minute using a fixed STM tip. It has been suggested that STM results obtained under ambient conditions must be evaluated with great care because of the possibility of localized electrochemcial reactions. A novel synthesis method for the production of Cu(II) oxide from an alkaline solution containing Cu(II) tartrate was developed. Rietveld refinement of the cupric oxide films reveals pure Cu(II) oxide with no Cu(I) oxide present in the film.

Stable room-temperature thallium bromide semiconductor radiation detectors

NASA Astrophysics Data System (ADS)

Datta, A.; Fiala, J.; Becla, P.; Motakef, Shariar

2017-10-01

Thallium bromide (TlBr) is a highly efficient ionic semiconductor with excellent radiation detection properties. However, at room temperature, TlBr devices polarize under an applied electric field. This phenomenon not only degrades the charge collection efficiency of the detectors but also promotes chemical reaction of the metal electrodes with bromine, resulting in an unstable electric field and premature failure of the device. This drawback has been crippling the TlBr semiconductor radiation detector technology over the past few decades. In this exhaustive study, this polarization phenomenon has been counteracted using innovative bias polarity switching schemes. Here the highly mobile Br- species, with an estimated electro-diffusion velocity of 10-8 cm/s, face opposing electro-migration forces during every polarity switch. This minimizes the device polarization and availability of Br- ions near the metal electrode. Our results indicate that it is possible to achieve longer device lifetimes spanning more than 17 000 h (five years of 8 × 7 operation) for planar and pixelated radiation detectors using this technique. On the other hand, at constant bias, 2500 h is the longest reported lifetime with most devices less than 1000 h. After testing several biasing switching schemes, it is concluded that the critical bias switching frequency at an applied bias of 1000 V/cm is about 17 μHz. Using this groundbreaking result, it will now be possible to deploy this highly efficient room temperature semiconductor material for field applications in homeland security, medical imaging, and physics research.

Value of Exercise Stress Electrocardiography for Risk Stratification in Patients With Suspected or Known Coronary Artery Disease in the Era of Advanced Imaging Technologies

PubMed Central

Bourque, Jamieson M.; Beller, George A.

2015-01-01

Exercise stress electrocardiography (ExECG) is underutilized as the initial test modality in patients with interpretable electrocardiograms able to exercise. Although, stress myocardial imaging techniques provide valuable diagnostic and prognostic information, variables derived from ExECG can yield substantial data for risk stratification, either supplementary to imaging variables, or without concurrent imaging. In addition to exercise-induced ischemic ST depression, such markers as ST segment elevation in lead AVR, abnormal heart rate recovery post-exercise, failure to achieve target heart rate, and poor exercise capacity improve risk stratification of ExECG. For example, patients achieving ≥10 METS on ExECG have a very low prevalence of inducible ischemia and an excellent prognosis. In contrast, cardiac imaging techniques add diagnostic and prognostic value in higher risk populations (e.g. poor functional capacity, diabetes, chronic kidney disease). Optimal test selection for symptomatic patients with suspected coronary artery disease requires a patient-centered approach factoring in the risk/benefit ratio and cost-effectiveness. PMID:26563861

Speckle Tracking Imaging in Normal Stress Echocardiography.

PubMed

Leitman, Marina; Tyomkin, Vladimir; Peleg, Eli; Zyssman, Izhak; Rosenblatt, Simcha; Sucher, Edgar; Gercenshtein, Vered; Vered, Zvi

2017-04-01

Exercise stress echocardiography is a widely used modality for the diagnosis and follow-up of patients with coronary artery disease. During the last decade, speckle tracking imaging has been used increasingly for accurate evaluation of cardiac function. This work aimed to assess speckle-tracking imaging parameters during nonischemic exercise stress echocardiography. During 2011 to 2014 we studied 46 patients without history of coronary artery disease, who completed exercise stress echocardiography protocol, had normal left ventricular function, a nonischemic response, and satisfactory image quality. These exams were analyzed with speckle-tracking imaging software at rest and at peak exercise. Peak strain and time-to-peak strain were measured at rest and after exercise. Clinical follow-up included a telephone contact 1 to 3 years after stress echo exam, confirming freedom from coronary events during this time. Global and regional peak strain increased following exercise. Time-to-peak global and regional strain and time-to-peak strain adjusted to the heart rate were significantly shorter in all segments after exercise. Rest-to-stress ratio of time-to-peak strain adjusted to the heart rate was 2.0 to 2.8. Global and regional peak strain rise during normal exercise echocardiography. Peak global and regional strain occur before or shortly after aortic valve closure at rest and after exercise, and the delay is more apparent at the basal segments. Time-to-peak strain normally shortens significantly during exercise; after adjustment to heart rate it shortens by a ratio of 2.0 to 2.8. These data may be useful for interpretation of future exercise stress speckle-tracking echocardiography studies. © 2016 by the American Institute of Ultrasound in Medicine.

Applicability of Cone Beam Computed Tomography to the Assessment of the Vocal Tract before and after Vocal Exercises in Normal Subjects.

PubMed

Garcia, Elisângela Zacanti; Yamashita, Hélio Kiitiro; Garcia, Davi Sousa; Padovani, Marina Martins Pereira; Azevedo, Renata Rangel; Chiari, Brasília Maria

2016-01-01

Cone beam computed tomography (CBCT), which represents an alternative to traditional computed tomography and magnetic resonance imaging, may be a useful instrument to study vocal tract physiology related to vocal exercises. This study aims to evaluate the applicability of CBCT to the assessment of variations in the vocal tract of healthy individuals before and after vocal exercises. Voice recordings and CBCT images before and after vocal exercises performed by 3 speech-language pathologists without vocal complaints were collected and compared. Each participant performed 1 type of exercise, i.e., Finnish resonance tube technique, prolonged consonant "b" technique, or chewing technique. The analysis consisted of an acoustic analysis and tomographic imaging. Modifications of the vocal tract settings following vocal exercises were properly detected by CBCT, and changes in the acoustic parameters were, for the most part, compatible with the variations detected in image measurements. CBCT was shown to be capable of properly assessing the changes in vocal tract settings promoted by vocal exercises. © 2017 S. Karger AG, Basel.

The effects of exercise on cigarette cravings and brain activation in response to smoking-related images.

PubMed

Janse Van Rensburg, Kate; Taylor, Adrian; Benattayallah, Abdelmalek; Hodgson, Tim

2012-06-01

Smokers show heightened activation toward smoking-related stimuli and experience increased cravings which can precipitate smoking cessation relapse. Exercise can be effective for modulating cigarette cravings and attenuating reactivity to smoking cues, but the mechanism by which these effects occur remains uncertain. The objective of the study was to assess the effect of exercise on regional brain activation in response to smoking-related images during temporary nicotine abstinence. In a randomised crossover design, overnight abstinent smokers (n = 20) underwent an exercise (10-min moderate-intensity stationary cycling) and passive control (seating for the same duration) treatment, following 15 h of nicotine abstinence. After each treatment, participants underwent functional magnetic resonance imaging (fMRI) brain scanning while viewing a random series of blocked smoking or neutral images. Self-reported cravings were assessed at baseline, mid-, and post-treatments. There was a significant interaction effect (treatment × time) for desire to smoke, F (2,32) = 12.5, p < 0.001, with significantly lower scores following the exercise at all time points compared with the control treatment. After both exercise and rest, significant areas of activation were found in areas of the limbic lobe and in areas associated with visual attention in response to smoking-related stimuli. Smokers showed increased activation to smoking images in areas associated with primary and secondary visual processing following rest, but not following a session of exercise. The study shows differing activation towards smoking images following exercise compared to a control treatment and may point to a neuro-cognitive process following exercise that mediates effects on cigarette cravings.

IQ-SPECT for thallium-201 myocardial perfusion imaging: effect of normal databases on quantification.

PubMed

Konishi, Takahiro; Nakajima, Kenichi; Okuda, Koichi; Yoneyama, Hiroto; Matsuo, Shinro; Shibutani, Takayuki; Onoguchi, Masahisa; Kinuya, Seigo

2017-07-01

Although IQ-single-photon emission computed tomography (SPECT) provides rapid acquisition and attenuation-corrected images, the unique technology may create characteristic distribution different from the conventional imaging. This study aimed to compare the diagnostic performance of IQ-SPECT using Japanese normal databases (NDBs) with that of the conventional SPECT for thallium-201 ( 201 Tl) myocardial perfusion imaging (MPI). A total of 36 patients underwent 1-day 201 Tl adenosine stress-rest MPI. Images were acquired with IQ-SPECT at approximately one-quarter of the standard time of conventional SPECT. Projection data acquired with the IQ-SPECT system were reconstructed via an ordered subset conjugate gradient minimizer method with or without scatter and attenuation correction (SCAC). Projection data obtained using the conventional SPECT were reconstructed via a filtered back projection method without SCAC. The summed stress score (SSS) was calculated using NDBs created by the Japanese Society of Nuclear Medicine working group, and scores were compared between IQ-SPECT and conventional SPECT using the acquisition condition-matched NDBs. The diagnostic performance of the methods for the detection of coronary artery disease was also compared. SSSs were 6.6 ± 8.2 for the conventional SPECT, 6.6 ± 9.4 for IQ-SPECT without SCAC, and 6.5 ± 9.7 for IQ-SPECT with SCAC (p = n.s. for each comparison). The SSS showed a strong positive correlation between conventional SPECT and IQ-SPECT (r = 0.921 and p < 0.0001), and the correlation between IQ-SPECT with and without SCAC was also good (r = 0.907 and p < 0.0001). Regarding diagnostic performance, the sensitivity, specificity, and accuracy were 80.8, 78.9, and 79.4%, respectively, for the conventional SPECT; 80.8, 80.3, and 82.0%, respectively, for IQ-SPECT without SCAC; and 88.5, 86.8, and 87.3%, respectively, for IQ-SPECT with SCAC, respectively. The area under the curve obtained via receiver operating characteristic analysis were 0.77, 0.80, and 0.86 for conventional SPECT, IQ-SPECT without SCAC, and IQ-SPECT with SCAC, respectively (p = n.s. for each comparison). When appropriate NDBs were used, the diagnostic performance of 201 Tl IQ-SPECT was comparable with that of the conventional system regardless of different characteristics of myocardial accumulation in the conventional system.

[18F]-FDG positron emission tomography--an established clinical tool opening a new window into exercise physiology.

PubMed

Rudroff, Thorsten; Kindred, John H; Kalliokoski, Kari K

2015-05-15

Positron emission tomography (PET) with [(18)F]-fluorodeoxyglucose (FDG) is an established clinical tool primarily used to diagnose and evaluate disease status in patients with cancer. PET imaging using FDG can be a highly valuable tool to investigate normal human physiology by providing a noninvasive, quantitative measure of glucose uptake into various cell types. Over the past years it has also been increasingly used in exercise physiology studies to identify changes in glucose uptake, metabolism, and muscle activity during different exercise modalities. Metabolically active cells transport FDG, an (18)fluorine-labeled glucose analog tracer, from the blood into the cells where it is then phosphorylated but not further metabolized. This metabolic trapping process forms the basis of this method's use during exercise. The tracer is given to a participant during an exercise task, and the actual PET imaging is performed immediately after the exercise. Provided the uptake period is of sufficient duration, and the imaging is performed shortly after the exercise; the captured image strongly reflects the metabolic activity of the cells used during the task. When combined with repeated blood sampling to determine tracer blood concentration over time, also known as the input function, glucose uptake rate of the tissues can be quantitatively calculated. This synthesis provides an accounting of studies using FDG-PET to measure acute exercise-induced skeletal muscle activity, describes the advantages and limitations of this imaging technique, and discusses its applications to the field of exercise physiology. Copyright © 2015 the American Physiological Society.

Submaximal delayed-onset muscle soreness: correlations between MR imaging findings and clinical measures

NASA Technical Reports Server (NTRS)

Evans, G. F.; Haller, R. G.; Wyrick, P. S.; Parkey, R. W.; Fleckenstein, J. L.; Blomqvist, C. G. (Principal Investigator)

1998-01-01

PURPOSE: To assess correlations between muscle edema on magnetic resonance (MR) images and clinical indexes of muscle injury in delayed-onset muscle soreness (DOMS) produced by submaximal exercise protocols. MATERIALS AND METHODS: Sixteen subjects performed 36 elbow flexions ("biceps curls") at one of two submaximal workloads that emphasized eccentric contractions. Changes in MR imaging findings, plasma levels of creatine kinase, and pain scores were correlated. RESULTS: Both exercise protocols produced DOMS in all subjects. The best correlation was between change in creatine kinase level and volume of muscle edema on MR images, regardless of the workload. Correlations tended to be better with the easier exercise protocol. CONCLUSION: Whereas many previous studies of DOMS focused on intense exercise protocols to ensure positive results, the present investigation showed that submaximal workloads are adequate to produce DOMS and that correlations between conventionally measured indexes of injury may be enhanced at lighter exercise intensities.

The effects of exposure to muscular male models among men: exploring the moderating role of gym use and exercise motivation.

PubMed

Halliwell, Emma; Dittmar, Helga; Orsborn, Amber

2007-09-01

This study examines the effects of exposure to the muscular male body ideal on body-focused negative affect among male gym users and non-exercisers. As hypothesized, the impact of media exposure depended on men's exercise status. Non-exercisers (n = 58) reported greater body-focused negative affect after exposure to images of muscular male models than after neutral images (no model controls), whereas gym users (n = 58) showed a tendency for less body-focused negative affect after the model images than after the control images. Furthermore, the extent to which gym users were motivated to increase strength and muscularity moderated these exposure effects; men who reported stronger strength and muscularity exercise motivation reported a greater degree of self-enhancement after exposure to the muscular ideal. The findings are interpreted with respect to likely differences in motives for social comparisons.

Theoretical investigations on structural, elastic and electronic properties of thallium halides

NASA Astrophysics Data System (ADS)

Singh, Rishi Pal; Singh, Rajendra Kumar; Rajagopalan, Mathrubutham

2011-04-01

Theoretical investigations on structural, elastic and electronic properties, viz. ground state lattice parameter, elastic moduli and density of states, of thallium halides (viz. TlCl and TlBr) have been made using the full potential linearized augmented plane wave method within the generalized gradient approximation (GGA). The ground state lattice parameter and bulk modulus and its pressure derivative have been obtained using optimization method. Young's modulus, shear modulus, Poisson ratio, sound velocities for longitudinal and shear waves, Debye average velocity, Debye temperature and Grüneisen parameter have also been calculated for these compounds. Calculated structural, elastic and other parameters are in good agreement with the available data.

Distributions and concentrations of thallium in surface waters of a region impacted by historical metal mining (Cornwall, UK).

PubMed

Tatsi, Kristi; Turner, Andrew

2014-03-01

Thallium is a highly toxic heavy metal whose concentrations and distributions in the aquatic environment are poorly defined. In this study, concentrations of aqueous and total Tl have been measured in water samples from a variety of rivers and effluents (the latter related to historical metal mining) in the county of Cornwall, SW England. Aqueous concentrations ranged from about 13 ng L(-1) in a river whose catchment contained no metal mines to 2,640 ng L(-1) in water abstracted directly from an abandoned mine shaft. Concentrations of Tl in rivers were greatest in the vicinity of mine-related effluents, with a maximum value measured of about 770 ng L(-1). Thallium was not efficiently removed by the conventional, active treatment of mine water, and displayed little interaction with suspended particles. Its mobility in surface waters, coupled with concentrations that are close to a quality guideline of 800 ng L(-1), is cause for concern. Accordingly, we recommend that the metal is more closely monitored in this and other regions impacted by mining activities. Copyright © 2013 Elsevier B.V. All rights reserved.

Application of Hyphenated Techniques in Speciation Analysis of Arsenic, Antimony, and Thallium

PubMed Central

Michalski, Rajmund; Szopa, Sebastian; Jabłońska, Magdalena; Łyko, Aleksandra

2012-01-01

Due to the fact that metals and metalloids have a strong impact on the environment, the methods of their determination and speciation have received special attention in recent years. Arsenic, antimony, and thallium are important examples of such toxic elements. Their speciation is especially important in the environmental and biomedical fields because of their toxicity, bioavailability, and reactivity. Recently, speciation analytics has been playing a unique role in the studies of biogeochemical cycles of chemical compounds, determination of toxicity and ecotoxicity of selected elements, quality control of food products, control of medicines and pharmaceutical products, technological process control, research on the impact of technological installation on the environment, examination of occupational exposure, and clinical analysis. Conventional methods are usually labor intensive, time consuming, and susceptible to interferences. The hyphenated techniques, in which separation method is coupled with multidimensional detectors, have become useful alternatives. The main advantages of those techniques consist in extremely low detection and quantification limits, insignificant interference, influence as well as high precision and repeatability of the determinations. In view of their importance, the present work overviews and discusses different hyphenated techniques used for arsenic, antimony, and thallium species analysis, in different clinical, environmental and food matrices. PMID:22654649

Novel KCNQ2 channel activators discovered using fluorescence-based and automated patch-clamp-based high-throughput screening techniques

PubMed Central

Yue, Jin-feng; Qiao, Guan-hua; Liu, Ni; Nan, Fa-jun; Gao, Zhao-bing

2016-01-01

Aim: To establish an improved, high-throughput screening techniques for identifying novel KCNQ2 channel activators. Methods: KCNQ2 channels were stably expressed in CHO cells (KCNQ2 cells). Thallium flux assay was used for primary screening, and 384-well automated patch-clamp IonWorks Barracuda was used for hit validation. Two validated activators were characterized using a conventional patch-clamp recording technique. Results: From a collection of 80 000 compounds, the primary screening revealed a total of 565 compounds that potentiated the fluorescence signals in thallium flux assay by more than 150%. When the 565 hits were examined in IonWorks Barracuda, 38 compounds significantly enhanced the outward currents recorded in KCNQ2 cells, and were confirmed as KCNQ2 activators. In the conventional patch-clamp recordings, two validated activators ZG1732 and ZG2083 enhanced KCNQ2 currents with EC50 values of 1.04±0.18 μmol/L and 1.37±0.06 μmol/L, respectively. Conclusion: The combination of thallium flux assay and IonWorks Barracuda assay is an efficient high-throughput screening (HTS) route for discovering KCNQ2 activators. PMID:26725738

Anomalous magneto-elastic and charge doping effects in thallium-doped BaFe 2As 2

DOE PAGES

Sefat, Athena S.; Li, Li; Cao, Huibo B.; ...

2016-02-12

Within the BaFe 2As 2 crystal lattice, we partially substitute thallium for barium and report the effects of interlayer coupling in Ba 1-xTl xFe 2As 2 crystals. We demonstrate the unusual effects of magneto-elastic coupling and charge doping in this iron-arsenide material, whereby Néel temperature rises with small x, and then falls with additional x. Specifically, we find that Néel and structural transitions in BaFe 2As 2 (T N = T s = 133 K) increase for x = 0.05 (T N = 138 K, T s = 140 K) from magnetization, heat capacity, resistivity, and neutron diffraction measurements. Evidencemore » from single crystal X-ray diffraction and first principles calculations attributes the stronger magnetism in x = 0.05 to magneto-elastic coupling related to the shorter intraplanar Fe-Fe bond distance. With further thallium substitution, the transition temperatures decrease for x = 0.09 (T N = T s = 131 K), and this is due to charge doping. Lastly, we illustrate that small changes related to 3d transition-metal state can have profound effects on magnetism.« less

Anomalous magneto-elastic and charge doping effects in thallium-doped BaFe2As2

PubMed Central

Sefat, Athena S.; Li, Li; Cao, Huibo B.; McGuire, Michael A.; Sales, Brian; Custelcean, Radu; Parker, David S.

2016-01-01

Within the BaFe2As2 crystal lattice, we partially substitute thallium for barium and report the effects of interlayer coupling in Ba1-xTlxFe2As2 crystals. We demonstrate the unusual effects of magneto-elastic coupling and charge doping in this iron-arsenide material, whereby Néel temperature rises with small x, and then falls with additional x. Specifically, we find that Néel and structural transitions in BaFe2As2 (TN = Ts = 133 K) increase for x = 0.05 (TN = 138 K, Ts = 140 K) from magnetization, heat capacity, resistivity, and neutron diffraction measurements. Evidence from single crystal X-ray diffraction and first principles calculations attributes the stronger magnetism in x = 0.05 to magneto-elastic coupling related to the shorter intraplanar Fe-Fe bond distance. With further thallium substitution, the transition temperatures decrease for x = 0.09 (TN = Ts = 131 K), and this is due to charge doping. We illustrate that small changes related to 3d transition-metal state can have profound effects on magnetism. PMID:26867821

Osteochondral lesions in developing rats intoxicated with thallium twenty four hours after birth.

PubMed

Barroso-Moguel, R; Villeda-Hernández, J; Méndez-Armenta, M; Ríos, C; Galván-Arzate, S

1992-01-01

An i.p. injection of a solution of thallium acetate in deionized water at a dose of 32 mg/kg, in 24-h-old rats, produces morphological and biochemical alterations in both cartilaginous and osseous tissues. From the beginning, there are alterations in the cartilaginous cell as well as in chrondrine, osteoblasts, osseous tissue and bone marrow. Rats were sacrificed at 24, 48, and 72 h and also at 7 days. Two animals survived for 50 days. One showed total irreversible alopecia while the other one had partial alopecia with discrete recovery. Both showed a low weight and a size of 8 cm. Microscopically, degenerative changes were produced consisting of alteration and death of many cartilaginous cells, uneven metachromasia and the chondrine and decrease of the growth cartilage, scanty bone trabeculae with few osteoblasts. The bone marrow showed few myeloblasts and megakaryocytes. Progressive cellular damage throughout the 50 days of survival represents a response of the thallium ionic accumulation and recycling in cellular mitochondria of all the body's cells. This appeared in our study as irreversible and progressive osteochondral alterations with atrophy of the skin and its adnexa, hyalinization of elastic and collagenous fibers with intense interstitial edema.

Breakfast food health and acute exercise: Effects on state body image.

PubMed

Hayes, Jacqueline F; Giles, Grace E; Mahoney, Caroline R; Kanarek, Robin B

2018-05-10

Food intake and exercise have been shown to alter body satisfaction in a state-dependent manner. One-time consumption of food perceived as unhealthy can be detrimental to body satisfaction, whereas an acute bout of moderate-intensity aerobic exercise can be beneficial. The current study examined the effect of exercise on state body image and appearance-related self-esteem following consumption of isocaloric foods perceived as healthy or unhealthy in 36 female college students (18-30 years old) in the Northeastern United States. Using a randomized-controlled design, participants attended six study sessions with breakfast conditions (healthy, unhealthy, no food) and activity (exercise, quiet rest) as within-participants factors. Body image questionnaires were completed prior to breakfast condition, between breakfast and activity conditions, and following activity condition. Results showed that consumption of an unhealthy breakfast decreased appearance self-esteem and increased body size perception, whereas consumption of a healthy breakfast did not influence appearance self-esteem but increased body size perception. Exercise did not influence state body image attitudes or perceptions following meal consumption. Study findings suggest that morning meal type, but not aerobic exercise, influence body satisfaction in college-aged females. Copyright © 2018. Published by Elsevier Ltd.

Prospective evaluation of a new protocol for the provisional use of perfusion imaging with exercise stress testing.

PubMed

Duvall, W Lane; Savino, John A; Levine, Elliot J; Hermann, Luke K; Croft, Lori B; Henzlova, Milena J

2015-02-01

Previous literature suggests that myocardial perfusion imaging (MPI) adds little to the prognosis of patients who exercise >10 metabolic equivalents (METs) during stress testing. With this in mind, we prospectively tested a provisional injection protocol in emergency department (ED) patients presenting for the evaluation of chest pain in which a patient would not receive an injection of radioisotope if adequate exercise was achieved without symptoms and a negative ECG response. All patients who presented to the ED over a 5-year period who were referred for stress testing as part of their ED evaluation were included. Patients considered for a provisional protocol were: exercise stress, age <65 years, no known coronary artery disease, and an interpretable rest ECG. Criteria for not injecting included a maximal predicted heart rate ≥85%, ≥10 METs of exercise, no anginal symptoms during stress, and no ECG changes. Groups were compared based on stress test results, all-cause and cardiac mortality, follow-up cardiac testing, subsequent revascularization, and cost. A total of 965 patients were eligible with 192 undergoing exercise-only and 773 having perfusion imaging. After 41.6 ± 19.6 months of follow-up, all-cause mortality was similar in the exercise-only versus the exercise plus imaging group (2.6% vs. 2.1%, p = 0.59). There were no cardiac deaths in the exercise-only group. At 1 year there was no difference in the number of repeat functional stress tests (1.6% vs. 2.1%, p = 0.43), fewer angiograms (0% vs. 4.0%, p = 0.002), and a significantly lower cost ($65 ± $332 vs $506 ± $1,991, p = 0.002; values are in US dollars) in the exercise-only group. The radiation exposure in the exercise plus imaging group was 8.4 ± 2.1 mSv. A provisional injection protocol has a very low mortality, few follow-up diagnostic tests, and lower cost compared to standard imaging protocols. If adopted it would decrease radiation exposure, save time and decrease health-care costs without jeopardizing prognosis.

Triggered intravoxel incoherent motion MRI for the assessment of calf muscle perfusion during isometric intermittent exercise.

PubMed

Mastropietro, Alfonso; Porcelli, Simone; Cadioli, Marcello; Rasica, Letizia; Scalco, Elisa; Gerevini, Simonetta; Marzorati, Mauro; Rizzo, Giovanna

2018-06-01

The main aim of this paper was to propose triggered intravoxel incoherent motion (IVIM) imaging sequences for the evaluation of perfusion changes in calf muscles before, during and after isometric intermittent exercise. Twelve healthy volunteers were involved in the study. The subjects were asked to perform intermittent isometric plantar flexions inside the MRI bore. MRI of the calf muscles was performed on a 3.0 T scanner and diffusion-weighted (DW) images were obtained using eight different b values (0 to 500 s/mm 2 ). Acquisitions were performed at rest, during exercise and in the subsequent recovery phase. A motion-triggered echo-planar imaging DW sequence was implemented to avoid movement artifacts. Image quality was evaluated using the average edge strength (AES) as a quantitative metric to assess the motion artifact effect. IVIM parameters (diffusion D, perfusion fraction f and pseudo-diffusion D*) were estimated using a segmented fitting approach and evaluated in gastrocnemius and soleus muscles. No differences were observed in quality of IVIM images between resting state and triggered exercise, whereas the non-triggered images acquired during exercise had a significantly lower value of AES (reduction of more than 20%). The isometric intermittent plantar-flexion exercise induced an increase of all IVIM parameters (D by 10%; f by 90%; D* by 124%; fD* by 260%), in agreement with the increased muscle perfusion occurring during exercise. Finally, IVIM parameters reverted to the resting values within 3 min during the recovery phase. In conclusion, the IVIM approach, if properly adapted using motion-triggered sequences, seems to be a promising method to investigate muscle perfusion during isometric exercise. Copyright © 2018 John Wiley & Sons, Ltd.

Exercise-associated Excessive Dynamic Airway Collapse in Military Personnel.

PubMed

Weinstein, Daniel J; Hull, James E; Ritchie, Brittany L; Hayes, Jackie A; Morris, Michael J

2016-09-01

Evaluation of military personnel for exertional dyspnea can present a diagnostic challenge, given multiple unique factors that include wide variation in military deployment. Initial consideration is given to common disorders such as asthma, exercise-induced bronchospasm, and inducible laryngeal obstruction. Excessive dynamic airway collapse has not been reported previously as a cause of dyspnea in these individuals. To describe the clinical and imaging characteristics of military personnel with exertional dyspnea who were found to have excessive dynamic collapse of large airways during exercise. After deployment to Afghanistan or Iraq, 240 active U.S. military personnel underwent a standardized evaluation to determine the etiology of persistent dyspnea on exertion. Study procedures included full pulmonary function testing, impulse oscillometry, exhaled nitric oxide measurement, methacholine challenge testing, exercise laryngoscopy, cardiopulmonary exercise testing, and fiberoptic bronchoscopy. Imaging included high-resolution computed tomography with inspiratory and expiratory views. Selected individuals underwent further imaging with dynamic computed tomography. A total of five men and one woman were identified as having exercise-associated excessive dynamic airway collapse on the basis of the following criteria: (1) exertional dyspnea without resting symptoms, (2) focal expiratory wheezing during exercise, (3) functional collapse of the large airways during bronchoscopy, (4) expiratory computed tomographic imaging showing narrowing of a large airway, and (5) absence of underlying apparent pathology in small airways or pulmonary parenchyma. Identification of focal expiratory wheezing correlated with bronchoscopic and imaging findings. Among 240 military personnel evaluated after presenting with postdeployment exertional dyspnea, a combination of symptoms, auscultatory findings, imaging, and visualization of the airways by bronchoscopy identified six individuals with excessive dynamic central airway collapse as the sole apparent cause of dyspnea. Exercise-associated excessive dynamic airway collapse should be considered in the differential diagnosis of exertional dyspnea.

Health perceptions, self and body image, physical activity and nutrition among undergraduate students in Israel.

PubMed

Korn, Liat; Gonen, Ester; Shaked, Yael; Golan, Moria

2013-01-01

This study examines health perceptions, self and body image, physical exercise and nutrition among undergraduate students. A structured, self-reported questionnaire was administered to more than 1500 students at a large academic institute in Israel. The study population was heterogenic in both gender and fields of academic study. High correlations between health perceptions, appropriate nutrition, and positive self and body image were found. The relationships between these variables differed between the subpopulation in the sample and the different genders. Engagement in physical exercise contributed to positive body image and positive health perceptions more than engagement in healthy nutrition. Nutrition students reported higher frequencies of positive health perceptions, positive self and body image and higher engagement in physical exercise in comparison to all other students in the sample. This study suggests, as have many before, that successful health promotion policy should reflect a collectivist rather than an individualist ethos by providing health prerequisites through a public policy of health-promotion, where the academic settings support a healthy lifestyle policy, by increasing availability of a healthy, nutritious and varied menu in the cafeterias, and offering students various activities that enhance healthy eating and exercise. IMPLICATIONS AND CONTRIBUTION: This study examined health perceptions, self-image, physical exercise and nutrition among undergraduate students and found high correlations between these topics. Nutrition students reported higher frequencies of positive health perceptions, and positive self and body image and engaged more in physical exercise when compared with all other students in the sample.

Limb Stress-Rest Perfusion Imaging With Contrast Ultrasound For The Assessment Of Peripheral Arterial Disease Severity

PubMed Central

Lindner, Jonathan R.; Womack, Lisa; Barrett, Eugene J.; Feltman, Judy; Price, Wendy; Harthun, Nancy L.; Kaul, Sanjiv; Patrie, James T.

2009-01-01

Objectives We hypothesized that lower extremity stress-rest perfusion imaging with contrast-enhanced ultrasound (CEU) could evaluate the severity of peripheral arterial disease (PAD). Background Perfusion imaging may provide valuable quantitative information on PAD, particularly in patients with diabetes in whom microvascular functional abnormalities are common. Methods Twenty-six control subjects and 39 patients with symptomatic PAD, 19 with type-2 diabetes mellitus, were studied. Claudication threshold was determined by a modified treadmill exercise test. Bilateral pulse-volume recordings, ankle-brachial index (ABI), and post-exercise ABI were performed. CEU perfusion imaging of the gastrocnemius and soleus was performed at rest and after 2 min of plantar-flexion exercise. Results During exercise, claudication occurred earlier in PAD patients with diabetes than without. Muscle blood flow during plantar-flexion exercise was lower (p<0.05) in patients with PAD (10.4±6.7) and PAD with diabetes (7.9±5.9) compared to control subjects (20.0±9.5). After adjusting for diabetes, the only diagnostic tests that predicted severity of disease defined by claudication threshold were CEU exercise blood flow (odds ratios: 0.67 [95% CI (0.51 to 0.88); p=0.003], and flow reserve (odds ratio: 0.64 [95% CI (0.46 to 0.89), p=0.008]). A multivariate model incorporating all non-invasive diagnostic tests indicated that the best models for predicting severity of disease were the combination of presence of diabetes and either exercise blood flow or flow reserve. Conclusions Limb microvascular perfusion imaging during exercise can be evaluated by CEU. Skeletal muscle blood flow during exercise and flow reserve are impaired in patients with PAD and correlate with the severity of symptoms. PMID:19356447

Imaging the Ways to a Preferred Future.

ERIC Educational Resources Information Center

MacKenzie, Terri; Frommelt, Nancy

1985-01-01

Presents a series of exercises that can be used with any age level to stimulate visioning skills (e.g., dreaming, creating, intuiting, and imaging). The exercises focus on building imagination skills, guided imaging, envisioning the future that students would prefer, and creating a futures wheel. (DMM)

rCBF-SPECT in brain infarction: When does it predict outcome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Limburg, M.; van Royen, E.A.; Hijdra, A.

1991-03-01

We prospectively studied 26 patients with ischemic stroke within 24 hr, after 2 wk, and after 6 mo with thallium-201-diethyldithiocarbamate single-photon emission computed tomography (SPECT) and neurologic and functional assessments. The admission flow deficits correlated with outcome. The admission and 6-mo scores correlated with clinical conditions at each time. At 2 wk, the flow deficits were smaller and did not correlate with clinical parameters. Nor did the presence or absence of hyperfixation of the radiopharmaceutical. Six months after the infarct, the flow defect had decreased in 9 of 15 patients in whom three serial scans were available, with better clinicalmore » improvement than in the remaining six whose flow deficits increased. More patients in the first group had been treated randomly with the calcium-entry blocker flunarizine. SPECT imaging of rCBF within 24 hr after stroke correlates with clinical outcome and condition, whereas rCBF imaging at 2 wk after the stroke shows no clinical correlation.« less

Validation of early image acquisitions following Tc-99 m sestamibi injection using a semiconductors camera of cadmium-zinc-telluride.

PubMed

Meyer, Celine; Weinmann, Pierre

2017-08-01

Cadmium-zinc-telluride (CZT) cameras allow to decrease significantly the acquisition time of myocardial perfusion imaging (MPI), but the duration of the examination is still long. Therefore, this study was performed to test the feasibility of early imaging following injection of Tc-99 m sestamibi using a CZT camera. Seventy patients underwent both an early and a delayed image acquisition after exercise stress test (n = 30), dipyridamole stress test (n = 20), and at rest (n = 20). After injection of Tc-99 m sestamibi, the early image acquisition started on average within 5 minutes for the exercise and rest groups, and 3 minutes 30 seconds for the dipyridamole group. Two independent observers evaluated image quality and extracardiac uptake on four-point scales. The difference between early and later images for each patient was scored on a five-point scale. The image quality and extracardiac uptake of early and delayed image acquisitions were not different for the three groups (P > .05). There was no significant difference between early and delayed image acquisitions in the exercise, dipyridamole, and rest groups, respectively, in 63%, 40%, and 80% of cases. In the exercise group and rest group, a defect was only present in early MPI, respectively, in 13% and 20% of cases. A defect was only present in delayed images in 10% of cases in the exercise group and in 45% of cases in the dipyridamole group. There was no difference between early and later image acquisitions in terms of quality. This protocol reduces the length of the procedure for the patient. Beginning with early image acquisitions may help to overcome the artifacts that are observed at the delayed time.

p-Tertbutylcalix[4]arene nanoemulsion: preparation, characterization and comparative evaluation of its decontamination efficacy against Technetium-99m, Iodine-131 and Thallium-201.

PubMed

Rana, Sudha; Sharma, Navneet; Ojha, Himanshu; Shivkumar, Hosakote Gurumalappa; Sultana, Sarwat; Sharma, Rakesh Kumar

2014-05-01

This study aimed to develop p-tertbutylcalix[4]arene o/w nanoemulsion for decontamination of radioisotopes from skin. Formulation was characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), multi-photon confocal microscopy techniques and in vitro dissolution studies. In vivo evaluation of nano-emulsion was done using nuclear medicine technique. Stability studies and dermal toxicity studies were also carried out. Comparative decontamination efficacy (DE) studies were performed on synthetic human tissue equivalent material and Sprague Dawley rat against three commonly used medical radioisotopes, i.e., Technetium-99m ((99m)Tc), Iodine-131 ((131)I) and Thallium-201 ((201)Tl). Decontamination was performed using cotton swabs soaked in nanoemulsion at different time intervals of contaminants exposure. Whole body imaging and static counts were recorded using gamma camera before and after each decontamination attempt data was analyzed using one way analysis of variance (ANOVA) and found to be statistically significant (p<0.05). DE of the nanoemulsion loaded with p-tertbutylcalix[4]arene was observed to be 88±5%, 90±3% and 89±3% for (99m)Tc, (131)I and (201)Tl respectively. Dermal toxicity studies revealed no significant differences between treated and control animals. Skin histopathology slides with and without API (Active pharmaceutical ingredients) also found to be comparable. p-Tertbutylcalix[4]arene loaded nanoemulsion shows great promise for skin decontamination against broad ranges of radiological contaminants besides being stable and safe. Copyright © 2014 Elsevier B.V. All rights reserved.

Nuclear stress test

MedlinePlus

... Persantine stress test; Thallium stress test; Stress test - nuclear; Adenosine stress test; Regadenoson stress test; CAD - nuclear stress; Coronary artery disease - nuclear stress; Angina - nuclear ...

Determination of lead, uranium, thorium, and thallium in silicate glass standard materials by isotope dilution mass spectrometry

USGS Publications Warehouse

Barnes, I.L.; Garner, E.L.; Gramlich, J.W.; Moore, L.J.; Murphy, T.J.; Machlan, L.A.; Shields, W.R.; Tatsumoto, M.; Knight, R.J.

1973-01-01

A set of four standard glasses has been prepared which have been doped with 61 different elements at the 500-, 50-, 1-, and 0.02-ppm level. The concentrations of lead, uranium, thorium, and thallium have been determined by isotope dilution mass spectrometry at a number of points in each of the glasses. The results obtained from independent determinations in two laboratories demonstrate the homogeneity of the samples and that precision of the order of 0.5% (95% L.E.) may be obtained by the method even at the 20-ppb level for these elements. The chemical and mass spectrometric procedures necessary are presented.

Prediction of revascularization after myocardial perfusion SPECT by machine learning in a large population.

PubMed

Arsanjani, Reza; Dey, Damini; Khachatryan, Tigran; Shalev, Aryeh; Hayes, Sean W; Fish, Mathews; Nakanishi, Rine; Germano, Guido; Berman, Daniel S; Slomka, Piotr

2015-10-01

We aimed to investigate if early revascularization in patients with suspected coronary artery disease can be effectively predicted by integrating clinical data and quantitative image features derived from perfusion SPECT (MPS) by machine learning (ML) approach. 713 rest (201)Thallium/stress (99m)Technetium MPS studies with correlating invasive angiography with 372 revascularization events (275 PCI/97 CABG) within 90 days after MPS (91% within 30 days) were considered. Transient ischemic dilation, stress combined supine/prone total perfusion deficit (TPD), supine rest and stress TPD, exercise ejection fraction, and end-systolic volume, along with clinical parameters including patient gender, history of hypertension and diabetes mellitus, ST-depression on baseline ECG, ECG and clinical response during stress, and post-ECG probability by boosted ensemble ML algorithm (LogitBoost) to predict revascularization events. These features were selected using an automated feature selection algorithm from all available clinical and quantitative data (33 parameters). Tenfold cross-validation was utilized to train and test the prediction model. The prediction of revascularization by ML algorithm was compared to standalone measures of perfusion and visual analysis by two experienced readers utilizing all imaging, quantitative, and clinical data. The sensitivity of machine learning (ML) (73.6% ± 4.3%) for prediction of revascularization was similar to one reader (73.9% ± 4.6%) and standalone measures of perfusion (75.5% ± 4.5%). The specificity of ML (74.7% ± 4.2%) was also better than both expert readers (67.2% ± 4.9% and 66.0% ± 5.0%, P < .05), but was similar to ischemic TPD (68.3% ± 4.9%, P < .05). The receiver operator characteristics areas under curve for ML (0.81 ± 0.02) was similar to reader 1 (0.81 ± 0.02) but superior to reader 2 (0.72 ± 0.02, P < .01) and standalone measure of perfusion (0.77 ± 0.02, P < .01). ML approach is comparable or better than experienced readers in prediction of the early revascularization after MPS, and is significantly better than standalone measures of perfusion derived from MPS.

Regional myocardial velocity imaged by magnetic resonance in patients with ischaemic heart disease.

PubMed Central

Karwatowski, S P; Mohiaddin, R H; Yang, G Z; Firmin, D N; St John Sutton, M; Underwood, S R

1994-01-01

OBJECTIVE--To assess the pattern of global and regional left ventricular long axis motion during early diastole in patients with ischaemic heart disease with and without myocardial infarction using magnetic resonance velocity mapping. DESIGN--Prospective study of 26 patients with a history of myocardial infarction (age 29-78, mean 55 years) and 21 patients with coronary artery disease without infarction (age range 39-71, mean 58 years). Values were compared with a control group (19 controls, age 35-76, mean 52 years) with a low likelihood of cardiovascular disease. RESULTS--Regional long axis velocity varied with time and position around the ventricle. All measurements were taken at the time of maximum early diastolic long axis velocity. Patients with coronary artery disease without infarction had lower values for maximum (mean (SD)) (99 (30) v 125 (33) mm/s, P < 0.05) and mean peak early diastolic wall motion (63 (13) v 82 (22) mm/s, P < 0.05) than controls. The coefficient of variation showed greater inhomogeneity of relaxation in patients than in controls (38 (18)% v 27 (10)%). All values were lower in patients with previous infarction than in patients with coronary artery disease without infarction and normal subjects. In patients with previous myocardial infarction the maximum (mean (SD)) early diastolic velocity was 80 (22) mm/s (P < 0.01 compared with controls and P < 0.05 compared with patients without infarction) and the mean (SD) velocity was 47 (18) mm/s (P < 0.01 compared with controls). The coefficient of variation was greater (52 (33)%) than for controls (P < 0.05) and patients with coronary artery disease without infarction. 18 of 26 patients with previous myocardial infarction and 13 of 21 patients with coronary artery disease without infarction had regional abnormalities corresponding to areas of fixed or reversible ischaemia on exercise electrocardiography or thallium myocardial perfusion tomography. CONCLUSIONS--Magnetic resonance velocity mapping can be used to assess regional long axis myocardial velocity. Ischaemic heart disease causes alterations in the patterns of left ventricular long axis velocity during early diastole. Images PMID:7833190

The effects of high-intensity exercise on neural responses to images of food.

PubMed

Crabtree, Daniel R; Chambers, Edward S; Hardwick, Robert M; Blannin, Andrew K

2014-02-01

Acute bouts of high-intensity exercise modulate peripheral appetite regulating hormones to transiently suppress hunger. However, the effects of physical activity on central appetite regulation have yet to be fully investigated. We used functional magnetic resonance imaging (fMRI) to compare neural responses to visual food stimuli after intense exercise and rest. Fifteen lean healthy men [mean ± SD age: 22.5 ± 3.1 y; mean ± SD body mass index (in kg/m(2)): 24.2 ± 2.4] completed two 60-min trials-exercise (EX; running at ∼70% maximum aerobic capacity) and a resting control trial (REST)-in a counterbalanced order. After each trial, an fMRI assessment was completed in which images of high- and low-calorie foods were viewed. EX significantly suppressed subjective appetite responses while increasing thirst and core-body temperature. Furthermore, EX significantly suppressed ghrelin concentrations and significantly enhanced peptide YY release. Neural responses to images of high-calorie foods significantly increased dorsolateral prefrontal cortex activation and suppressed orbitofrontal cortex (OFC) and hippocampus activation after EX compared with REST. After EX, low-calorie food images increased insula and putamen activation and reduced OFC activation compared with REST. Furthermore, left pallidum activity was significantly elevated after EX when low-calorie images were viewed and was suppressed when high-calorie images were viewed, and these responses correlated significantly with thirst. Exercise increases neural responses in reward-related regions of the brain in response to images of low-calorie foods and suppresses activation during the viewing of high-calorie foods. These central responses are associated with exercise-induced changes in peripheral signals related to appetite-regulation and hydration status. This trial was registered at www.clinicaltrials.gov as NCT01926431.

Health Perceptions, Self and Body Image, Physical Activity and Nutrition among Undergraduate Students in Israel

PubMed Central

Korn, Liat; Gonen, Ester; Shaked, Yael; Golan, Moria

2013-01-01

Purpose This study examines health perceptions, self and body image, physical exercise and nutrition among undergraduate students. Methods A structured, self-reported questionnaire was administered to more than 1500 students at a large academic institute in Israel. The study population was heterogenic in both gender and fields of academic study. Results High correlations between health perceptions, appropriate nutrition, and positive self and body image were found. The relationships between these variables differed between the subpopulation in the sample and the different genders. Engagement in physical exercise contributed to positive body image and positive health perceptions more than engagement in healthy nutrition. Nutrition students reported higher frequencies of positive health perceptions, positive self and body image and higher engagement in physical exercise in comparison to all other students in the sample. Conclusions This study suggests, as have many before, that successful health promotion policy should reflect a collectivist rather than an individualist ethos by providing health prerequisites through a public policy of health-promotion, where the academic settings support a healthy lifestyle policy, by increasing availability of a healthy, nutritious and varied menu in the cafeterias, and offering students various activities that enhance healthy eating and exercise. Implications and contribution This study examined health perceptions, self-image, physical exercise and nutrition among undergraduate students and found high correlations between these topics. Nutrition students reported higher frequencies of positive health perceptions, and positive self and body image and engaged more in physical exercise when compared with all other students in the sample. PMID:23516503

Adolescent Male Athletes: Body Image, Diet, and Exercise.

ERIC Educational Resources Information Center

Parks, Pamela S. McKay; Read, Marsha H.

1997-01-01

Investigates and compares football players' (n=44) and cross-country runners' (n=30) body image concerns, attitudes toward eating, and reasons for exercising. Results revealed significant differences. Football players reported a more positive body image, whereas runners indicated a greater concern for weight control and more disordered eating…

The Relationships among Body Image, Body Mass Index, Exercise, and Sexual Functioning in Heterosexual Women

ERIC Educational Resources Information Center

Weaver, Angela D.; Byers, E. Sandra

2006-01-01

Problems related to negative body image are very common among young women. In this study, we examined the relationship between women's body image and their sexual functioning over and above the effects of physical exercise and body mass index (BMI) in a sample of 214 university women. Low situational body image dysphoria and low body…

Desulfurization Activated Phosphorothioate DNAzyme for the Detection of Thallium.

PubMed

Huang, Po-Jung Jimmy; Vazin, Mahsa; Liu, Juewen

2015-10-20

Thallium (Tl) is a highly toxic heavy metal situated between mercury and lead in the periodic table. While its neighbors have been thoroughly studied for DNA-based sensing, little is known about thallium detection. In this work, in vitro selection of RNA-cleaving DNAzymes is carried out using Tl(3+) as the target metal cofactor. Both normal DNA and phosphorothioate (PS)-modified DNA are tested for this purpose. While no Tl(3+)-dependent DNAzymes are obtained, a DNA oligonucleotide containing a single PS-modified RNA nucleotide is found to cleave by ∼7% by Tl(3+) at the RNA position. The remaining 93% are desulfurized. By hybridization of this PS-modified oligonucleotide with the Tm7 DNAzyme, the cleavage yield increases to ∼40% in the presence of Tl(3+) and Er(3+). Tm7 is an Er(3+)-dependent RNA-cleaving DNAzyme. It cleaves only the normal substrate but is completely inactive using the PS-modified substrate. Tl(3+) desulfurizes the PS substrate to the normal substrate to be cleaved by Tm7 and Er(3+). This system is engineered into a catalytic beacon for Tl(3+) with a detection limit of 1.5 nM, which is below its maximal contamination limit defined by the U.S. Environmental Protection Agency (10 nM).

Orthopedic pathology of the lower extremities: scintigraphic evaluation in the thigh, knee, and leg.

PubMed

Etchebehere, E C; Etchebehere, M; Gamba, R; Belangero, W; Camargo, E E

1998-01-01

Radionuclide imaging (RI) of the osseous and nonosseous structures of the thigh, knee, and leg provide important diagnostic and prognostic information upon which the orthopedic surgeon can base treatment planning and management decisions. 99mTc-MDP scintigraphy is essential in overuse injuries such as stress fractures and shin splints. RI is important in assessing complications of trauma. It is the only imaging modality able to assess the magnitude of physeal stimulus caused by femoral fractures and to predict a favorable or unfavorable outcome of leg length by semiquantitative analysis; SPECT imaging can detect and locate decreased metabolism associated with posttraumatic closure of the physeal plate to predict growth arrest and deformities. Three-phase bone imaging (TPBI) is essential to differentiate hypervascular from avascular nonunions and follow delayed union. In osteonecrosis of the knee, bone scintigraphy precedes radiography changes even in stage l of the disease. 99mTc-MDP and 99mTc-HIG imaging are powerful tools in determining the outcomes of osteoarthritis and rheumatoid arthritis, respectively. Bone scintigraphy can also detect chronic ligament and acute and chronic meniscal lesions. The combined use of TPBI, gallium-67 citrate imaging, and indium-111 or 99mTc-HMPAO labeled leukocytes is important to diagnose and differentiate acute from chronic osteomyelitis, and to detect infected knee prostheses. Thallium-201 chloride imaging and 99mTc-sestamibi imaging have an important role in the assessment of tumor response to chemotherapy and in the quantification of tumor viability.

Evaluation of Water Retention in Lumbar Intervertebral Disks Before and After Exercise Stress With T2 Mapping.

PubMed

Chokan, Kou; Murakami, Hideki; Endo, Hirooki; Mimata, Yoshikuni; Yamabe, Daisuke; Tsukimura, Itsuko; Oikawa, Ryosuke; Doita, Minoru

2016-04-01

T2 mapping was used to quantify moisture content of the lumbar spinal disk nucleus pulposus (NP) and annulus fibrosus before and after exercise stress, and after rest, to evaluate the intervertebral disk function. To clarify water retention in intervertebral disks of the lumbar vertebrae by performing magnetic resonance imaging before and after exercise stress and quantitatively measuring changes in moisture content of intervertebral disks with T2 mapping. To date, a few case studies describe functional evaluation of articular cartilage with T2 mapping; however, T2 mapping to the functional evaluation of intervertebral disks has rarely been applied. Using T2 mapping might help detect changes in the moisture content of intervertebral disks, including articular cartilage, before and after exercise stress, thus enabling the evaluation of changes in water retention shock absorber function. Subjects, comprising 40 healthy individuals (males: 26, females: 14), underwent magnetic resonance imaging T2 mapping before and after exercise stress and after rest. Image J image analysis software was then used to set regions of interest in the obtained images of the anterior annulus fibrosus, posterior annulus fibrosus, and NP. T2 values were measured and compared according to upper vertebrae position and degeneration grade. T2 values significantly decreased in the NP after exercise stress and significantly increased after rest. According to upper vertebrae position, in all of the upper vertebrae positions, T2 values for the NP significantly decreased after exercise stress and significantly increased after rest. According to the degeneration grade, in the NP of grade 1 and 2 cases, T2 values significantly decreased after exercise stress and significantly increased after rest. T2 mapping could be used to not only diagnose the degree of degeneration but also evaluate intervertebral disk function. 3.

A Novel Ion - selective Polymeric Membrane Sensor for Determining Thallium(I) With High Selectivity

NASA Astrophysics Data System (ADS)

Kassim, Anuar; Rezayi, Majid; Ahmadzadeh, Saeid; Rounaghi, Gholamhossein; Mohajeri, Masoomeh; Azah Yusof, Noor; Tee, Tan Wee; Yook Heng, Lee; Halim Abdullah, Abd

2011-02-01

Thallium is a toxic metal that introduced into the environment mainly as a waste from the production of zinc, cadmium, and lead and by combustion of coal. Thallium causes gastrointestinal irritation and nerve damage when people are exposed to it for relatively short period of time. For long term, thallium has the potential to cause the following effects: change in blood chemistry, damage to liver, kidney, intestinal and testicular tissue, and hair loss. In this work a membrane was prepared by use of 4'-nitrobenzo -18-crown-6 (4'NB18C6) as an ion carrier, polyvinylchloride (PVC) as a matrix, and diocthylphetalate (DOP) as a plasticizer for making an ion selective electrode for measurement of Tl+ cation in solutions. The amount of 4'-nitrobenzo-18C6 and polyvinylchloride were optimized in the preparation of the membrane. The response of the electrode was Nernstian within the concentration range 1.0 × 10-8 to 1.0 × 10-1M. This sensor displays a drift in Nernstian response for this cation with increasing the amount of ionophore and decreasing the amount of polyvinylchloride.The results of potentiometric measurements showed that, this electrode also responses to Cu2+ Ni2+ and Pb2+ cations, but the electrode has a wider dynamic range and a lower detection limit to Tl+ cation. The effects of various parameters such as pH, different cations interferences, effect of the amount of ionophore and polyvinylchloride and time on response of the coated ion selective electrode were investigated. Finally the constructed electrode was used in complexometric and precipitation titrations of Tl+ cation with EDTA and KBr, respectively. The response of the fabricated electrode at concentration range from 1.0 × 10-8 to 1.0 × 10-1M is linear with a Nernstian slope of 57.27 mV.

Desktop Parallax and Proper Motion: A Laboratory Exercise on Astrometry of Asteroids from Project CLEA

NASA Astrophysics Data System (ADS)

Marschall, L. A.; Snyder, G. A.; Good, R. F.; Hayden, M. B.; Cooper, P. R.

1998-12-01

Students in introductory and advanced astronomy classes can now experience the process of discovering asteroids, can measure proper motions, and can actually see the parallax of real astronomical objects on the screen, using a new set of computer-based exercises from Project CLEA. The heart of the exercise is a sophisticated astrometry program "Astrometry of Asteroids", which is a restricted version of CLEA's research software "Tools for Astrometry" described elsewhere at this meeting. The program, as used in the teaching lab, allows students to read and display digital images, co-align pairs of images using designated reference stars, blink and identify moving objects on the pairs, compare images with charts produced from the HST Guide Star Catalog (GSC), and fit equatorial coordinates to the images using designated reference stars from the GSC. Complete technical manuals for the exercise are provided for the use of the instructor, and a set of digital images, in FITS format, is included for the exercise. A student manual is provided for an exercise in which students go through the step-by-step process of determining the tangential velocity of an asteroid. Students first examine a series of images of a near-earth asteroid taken over several hours, blinking pairs to identify the moving object. They next measure the equatorial coordinates on a half-dozen images, and from this calculate an angular velocity of the object. Finally, using a pair of images of the asteroid taken simultaneously at the National Undergraduate Research Observatory (NURO) and at Colgate University, they measure the parallax of the asteroid, and thus its distance, which enables them to convert the angular velocity into a tangential velocity. An optional set of 10 pairs of images is provided, some of which contain asteroids, so that students can try to "find the asteroid" for themselves. The software is extremely flexible, and though materials are provided for a self-contained exercise, teachers can adapt the material to a wide variety of uses. The software and manuals are currently available on the Web. Project CLEA is supported by grants from Gettysburg College and the National Science Foundation.

This girl can #jointhemovement: Effectiveness of physical functionality-focused campaigns for women's body satisfaction and exercise intent.

PubMed

Mulgrew, Kate E; McCulloch, Karen; Farren, Emily; Prichard, Ivanka; Lim, Megan S C

2018-03-01

We tested the effectiveness of exposure to two functionality-focused media campaigns, This Girl Can and #jointhemovement, in improving state appearance and physical functionality satisfaction, exercise intent, and protecting against exposure to idealised imagery. Across two studies, 339 (M age =24.94, SD=4.98) and 256 (M age =26.46, SD=5.50) women viewed the campaign or control video, followed by images of models who were posed or physically active, or images of landscapes. State satisfaction and exercise intent was measured at pre-test, post-video, post-images, and 1-week follow-up. Social comparison was measured at post-images. Viewing either campaign produced higher appearance satisfaction and exercise intentions than the control video. Effects weren't maintained after viewing idealised imagery or 1 week later. Further, the campaigns did not decrease social comparisons when viewing idealised imagery. Results can inform agencies about campaign effectiveness and suggest that women benefit from campaigns that feature non-idealised depictions of women exercising. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Charge trapping in detector grade thallium bromide and cadmium zinc telluride: Measurement and theory

NASA Astrophysics Data System (ADS)

Elshazly, Ezzat S.; Tepper, Gary; Burger, Arnold

2010-08-01

Carrier trapping times were measured in detector grade thallium bromide (TlBr) and cadmium zinc telluride (CZT) from 300 to 110 K and the experimental data were analyzed using a trapping model. In CZT, because the majority carrier concentration is close to the intrinsic carrier concentration, the trapping time increases exponentially as the temperature decreases below about 160 K. In TlBr, the majority carrier concentration is many orders of magnitude greater than the intrinsic carrier concentration and the trapping time followed a (1/ T) 1/2 temperature dependence over the range of temperatures studied. The results of the model suggest that a moderately deep compensation center could be used to significantly increase the room temperature trapping time in TlBr.

Temperature Dependence of Thermodynamic Properties of Thallium Chloride and Thallium Bromide

NASA Astrophysics Data System (ADS)

Kavanoz, H. B.

2015-02-01

Thermodynamic properties as lattice parameters, thermal expansion, heat capacities Cp and Cv, bulk modulus, and Gruneisen parameter of ionic halides TlCl and TlBr in solid and liquid phases were studied using classical molecular dynamics simulation (MD) with interionic Vashistha-Rahman (VR) model potential. In addition to the static and transport properties which have been previously reported by the author [13], this study further confirms that temperature dependence of the calculated thermophysical properties of TlCl and TlBr are in agreement with the available experimental data at both solid and liquid phases in terms of providing an alternative rigid ion potential. The results give a fairly good description of TlCl and TlBr in the temperature range 10-1000 K.

Precise Measurement of Parity Nonconserving Optical Rotation in Atomic Thallium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, N.H.; Phipp, S.J.; Baird, P.E.G.

1995-04-03

We report a new measurement of parity nonconserving (PNC) optical rotation on the 6{ital p}{sub 1/2}-6{ital p}{sub 3/2} transition in atomic thallium near 1283 nm. The result expressed in terms of the quantity R=Im{l_brace}{ital E}1{sup PNC}/{ital M}1{r_brace} is {minus}(15.68{plus_minus}0.45){times}10{sup {minus}8}, and is consistent with current calculations based on the standard model. In addition, limits have been set on the much smaller nuclear spin-dependent rotation amplitude at R{sub {ital S}}=(0.04{plus_minus}0.20){times}10{sup {minus}8}; this is consistent with theoretical estimates which include a nuclear anapole contribution.

Antitumor Activity and Toxicity of Salts of Inorganic Group IIIa Metals: Aluminum, Gallium, Indium, and Thallium

PubMed Central

Hart, Michael M.; Adamson, Richard H.

1971-01-01

The toxicity and antitumor activity of salts of the Group IIIa metals aluminum, gallium, indium, and thallium were determined. With the (lethal dose)50 as a measure, the decreasing order of toxicity was TlCl3 ≥ In(NO3)3 > Ga(NO3)3 > Al(NO3)3. All four metals exhibited antitumor activity, but when the tumor was inoculated by a route different from that of the drug, only Ga+3 and, to a lesser extent, In+3 inhibited tumor growth. Ga(NO3)3 was found to inhibit the growth of three out of four rodent solid tumors. Gallium therefore has potential therapeutic usefulness for treatment of solid tumors in man. PMID:5283954

Comparison of three Bayesian methods to estimate posttest probability in patients undergoing exercise stress testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morise, A.P.; Duval, R.D.

To determine whether recent refinements in Bayesian methods have led to improved diagnostic ability, 3 methods using Bayes' theorem and the independence assumption for estimating posttest probability after exercise stress testing were compared. Each method differed in the number of variables considered in the posttest probability estimate (method A = 5, method B = 6 and method C = 15). Method C is better known as CADENZA. There were 436 patients (250 men and 186 women) who underwent stress testing (135 had concurrent thallium scintigraphy) followed within 2 months by coronary arteriography. Coronary artery disease ((CAD), at least 1 vesselmore » with greater than or equal to 50% diameter narrowing) was seen in 169 (38%). Mean pretest probabilities using each method were not different. However, the mean posttest probabilities for CADENZA were significantly greater than those for method A or B (p less than 0.0001). Each decile of posttest probability was compared to the actual prevalence of CAD in that decile. At posttest probabilities less than or equal to 20%, there was underestimation of CAD. However, at posttest probabilities greater than or equal to 60%, there was overestimation of CAD by all methods, especially CADENZA. Comparison of sensitivity and specificity at every fifth percentile of posttest probability revealed that CADENZA was significantly more sensitive and less specific than methods A and B. Therefore, at lower probability thresholds, CADENZA was a better screening method. However, methods A or B still had merit as a means to confirm higher probabilities generated by CADENZA (especially greater than or equal to 60%).« less

False-negative dipyridamole-thallium-201 myocardial imaging after caffeine infusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smits, P.; Corstens, F.H.; Aengevaeren, W.R.

1991-08-01

The vasodilator effect of intravenously administered dipyridamole may be caused by an increase in endogenous plasma adenosine levels. The authors evaluated the effect of caffeine, an adenosine receptor antagonist, on the diagnostic results of dipyridamole-201Tl myocardial imaging in eight patients with coronary artery disease. Caffeine infusion significantly attenuated the dipyridamole-induced fall in blood pressure and the accompanied increase in heart rate. The infusion of dipyridamole alone resulted in chest pain and ST-segment depressions on the electrocardiogram in four patients, whereas none of these problems occurred when the tests were repeated after caffeine. In six of eight patients, caffeine was responsiblemore » for false-negative dipyridamole-201Tl tests. Semiquantitive scores of the dipyridamole-induced 201Tl perfusion defects were decreased by caffeine from 9.0 {plus minus} 0.9 to 2.0 {plus minus} 1.1 points (p less than 0.05). Computerized analysis revealed a caffeine-mediated reduction in the percent reversibility of the images from 46% {plus minus} 16% to 6% {plus minus} 10% (p less than 0.05). They conclude that the use of caffeinated products prior to dipyridamole-201Tl testing may be responsible for false-negative findings.« less

SPECT and PET in ischemic heart failure.

PubMed

Angelidis, George; Giamouzis, Gregory; Karagiannis, Georgios; Butler, Javed; Tsougos, Ioannis; Valotassiou, Varvara; Giannakoulas, George; Dimakopoulos, Nikolaos; Xanthopoulos, Andrew; Skoularigis, John; Triposkiadis, Filippos; Georgoulias, Panagiotis

2017-03-01

Heart failure is a common clinical syndrome associated with significant morbidity and mortality worldwide. Ischemic heart disease is the leading cause of heart failure, at least in the industrialized countries. Proper diagnosis of the syndrome and management of patients with heart failure require anatomical and functional information obtained through various imaging modalities. Nuclear cardiology techniques play a main role in the evaluation of heart failure. Myocardial single photon emission computed tomography (SPECT) with thallium-201 or technetium-99 m labelled tracers offer valuable data regarding ventricular function, myocardial perfusion, viability, and intraventricular synchronism. Moreover, positron emission tomography (PET) permits accurate evaluation of myocardial perfusion, metabolism, and viability, providing high-quality images and the ability of quantitative analysis. As these imaging techniques assess different parameters of cardiac structure and function, variations of sensitivity and specificity have been reported among them. In addition, the role of SPECT and PET guided therapy remains controversial. In this comprehensive review, we address these controversies and report the advances in patient's investigation with SPECT and PET in ischemic heart failure. Furthermore, we present the innovations in technology that are expected to strengthen the role of nuclear cardiology modalities in the investigation of heart failure.

Comparison of personnel radiation dosimetry from myocardial perfusion scintigraphy: Technetium-99m-sestamibi versus thallium-201

DOE Office of Scientific and Technical Information (OSTI.GOV)

Culver, C.M.; Dworkin, H.J.

1993-07-01

The whole-body and hand radiation doses to our technical staff were retrospectively compared for three distinct 4-mo periods when either 201TI or 99mTc-sestamibi were exclusively used for stress myocardial perfusion imaging. During the initial 4-mo period when 99mTc-sestamibi replaced 201TI, the mean whole-body film badge readings increased from 100 to 450 microSv/mo (p < 0.001) for nuclear medicine technologists (n = 10) and from 240 to 560 microSv/mo (p < 0.05) for radiopharmacy technologists (n = 2). Mean TLD readings to the hands also increased, although the differences were not statistically significant for the nuclear medicine technologists. Noninvasive cardiology staffmore » were monitored with film badges and the mean whole-body film badge reading, when 99mTc-sestamibi was the imaging agent, was 360 microSv per month. Radiation reduction methods that decreased radiation exposure to staff were utilized. The most effective included the use of a lead face shield and lead lined storage container in the noninvasive imaging area, handling spills by shielding instead of decontamination and methods to reduce time spent in close proximity to the patient.« less

SOLAR ROTATION: A Laboratory Exercise from Project CLEA and the GONG Project

NASA Astrophysics Data System (ADS)

Marschall, L. A.; Sudol, J. J.; Snyder, G. A.

2002-12-01

Digital images from the GONG Project provide a nearly continuous record of sunspots that are ideal for determining the rate of rotation of the Sun. A new laboratory exercise from Project CLEA provides students with the capability to access an archive of 368 images of the Sun obtained at GONG solar telescopes between January 1, 2002 and April 30, 2002, during a period near solar maximum when large numbers of spots were daily visible on the sun. The resolution of each image is about 2.5 arcsec per pixel (or about 0.25 degree in longitude and latitude at the center of the solar disk). Because these images have such exquisite spatial and temporal resolution, they are the best images to date from which students can determine the solar rotation rate. CLEA software for this exercise allows students to select images by date and time, to overlay a coordinate grid on the image, and to record the latitudes and longitudes of sunspots. This data can be tabulated and analyzed with the software to determine solar rotation rates. The expected precision in the solar rotation rates is +/- 3 hours. Students will also have the ability to combine their chosen images into a digital movie showing the solar rotation. The exercise includes a student workbook and a technical manual, as well as a CD-rom of the data and the software. This exercise was produced with funding from the National Science Foundation and Gettysburg College and with the support of the GONG Project at the National Solar Observatory.

The implementation of CMOS sensors within a real time digital mammography intelligent imaging system: The I-ImaS System

NASA Astrophysics Data System (ADS)

Esbrand, C.; Royle, G.; Griffiths, J.; Speller, R.

2009-07-01

The integration of technology with healthcare has undoubtedly propelled the medical imaging sector well into the twenty first century. The concept of digital imaging introduced during the 1970s has since paved the way for established imaging techniques where digital mammography, phase contrast imaging and CT imaging are just a few examples. This paper presents a prototype intelligent digital mammography system designed and developed by a European consortium. The final system, the I-ImaS system, utilises CMOS monolithic active pixel sensor (MAPS) technology promoting on-chip data processing, enabling the acts of data processing and image acquisition to be achieved simultaneously; consequently, statistical analysis of tissue is achievable in real-time for the purpose of x-ray beam modulation via a feedback mechanism during the image acquisition procedure. The imager implements a dual array of twenty 520 pixel × 40 pixel CMOS MAPS sensing devices with a 32μm pixel size, each individually coupled to a 100μm thick thallium doped structured CsI scintillator. This paper presents the first intelligent images of real breast tissue obtained from the prototype system of real excised breast tissue where the x-ray exposure was modulated via the statistical information extracted from the breast tissue itself. Conventional images were experimentally acquired where the statistical analysis of the data was done off-line, resulting in the production of simulated real-time intelligently optimised images. The results obtained indicate real-time image optimisation using the statistical information extracted from the breast as a means of a feedback mechanisms is beneficial and foreseeable in the near future.

Pharmacokinetics and Scintigraphic Imaging of the Hypoxia-Imaging Agent [123I]IAZA in Healthy Adults Following Exercise-Based Cardiac Stress †

PubMed Central

Stypinski, Daria; McQuarrie, Stephen A.; McEwan, Alexander J. B.; Wiebe, Leonard I.

2018-01-01

The objective of this work is to evaluate the potential effect of cardiac stress exercise on the accumulation of [123I]IAZA, a radiopharmaceutical used to image focal tissue hypoxia, in otherwise normal myocardium in healthy volunteers, and to determine the impact of exercise on [123I]IAZA pharmacokinetics. The underlying goal is to establish a rational basis and a baseline for studies of focal myocardial hypoxia in cardiac patients using [123I]IAZA. Three healthy male volunteers ran the ‘Bruce’ treadmill protocol, a clinically-accepted protocol designed to expose myocardial ischemia in patients. The ‘Bruce’ criterion heart rate is 85% of [220–age]. Approximately one minute before reaching this level, [123I]IAZA (5.0 mCi/0.85 mg) was administered as a slow (1–3 min) single intravenous (i.v.) injection via an indwelling venous catheter. The volunteer continued running for an additional 1 min before being transferred to a gamma camera. Serum samples were collected from the arm contralateral to the administration site at pre-determined intervals from 1 min to 45 h post injection and were analyzed by radio HPLC. Pharmacokinetic (PK) parameters were derived for [123I]IAZA and total radioactivity (total[123I]) using compartmental and noncompartmental analyses. Whole-body planar scintigraphic images were acquired from 0.75 to 24 h after dosing. PK data and scintigraphic images were compared to previously published [123I]IAZA data from healthy volunteers rest. Following exercise stress, both [123I]IAZA and total[123I] exhibited bi-exponential decline profiles, with rapid distribution phases [half-lives (t1/2α) of 1.2 and 1.4 min, respectively], followed by slower elimination phases [t1/2β of 195 and 290 min, respectively]. Total body clearance (CLTB) and the steady state volume of distribution (Vss) were 0.647 L/kg and 185 mL/min, respectively, for [123I]IAZA and 0.785 L/kg and 135 mL/min, respectively, for total[123I]. The t1/2β, CLTB and Vss values were comparable to those reported previously for rested volunteers. The t1/2α was approximately 4-fold shorter for [123I]IAZA and approximately 3-fold shorter for total[123I] under exercise relative to rested subjects. The heart region was visualized in early whole body scintigraphic images, but later images showed no accumulated radioactivity in this region, and no differences from images reported for rested volunteers were apparent. Minimal uptake of radiotracer in myocardium and skeletal muscle was consistent with uptake in non-stressed myocardium. Whole-body scintigrams for [123I]IAZA in exercise-stressed healthy volunteers were indistinguishable from images of non-exercised volunteers. There was no evidence of hypoxia-dependent binding in exercised but otherwise healthy myocardium, supporting the conclusion that exercise stress at Bruce protocol intensity does not induce measurable myocardial hypoxia. Effects of exercise on PK parameters were minimal; specifically, the t1/2α was shortened, reflecting increased cardiac output associated with exercise. It is concluded that because [123I]IAZA was not metabolically bound in exercise-stressed myocardium, a stress test will not create elevated myocardial background that would mask regions of myocardial perfusion deficiency. [123I]IAZA would therefore be suitable for the detection of viable, hypoxic myocardium in patients undergoing stress-test-based diagnosis. PMID:29470434

Isometric exercise (image)

MedlinePlus

Isometric exercise works muscles and strengthens bone. Increased muscle mass elevates metabolism, which in turn burns fat. Strength training is also called anaerobic exercise, as opposed to aerobic, because increased oxygen production is not ...

Aerobic exercise (image)

MedlinePlus

Aerobic exercise gets the heart working to pump blood through the heart more quickly and with more ... must be oxygenated more quickly, which quickens respiration. Aerobic exercise strengthens the heart and boosts healthy cholesterol ...

Spectroscopy and imaging of oxygen delivery to tissue under strenuous conditions (NIR in athletes)

NASA Astrophysics Data System (ADS)

Chance, Britton; Nioka, Shoko; Long, Hong; Xie, Chunhua; Ma, XuHui; Ntziachristos, Vasilis; Luo, Qingming

2000-04-01

It was demonstrated that the dynamics of muscle oxygen utilization can readily be measured using dual wavelength hemoglobin oximetry. This method can be used for muscle training exercise and also for evaluation of exercise performance where the anaerobic threshold must be avoided. It was shown that CW imaging technology gives images along the surface of the muscle while the time resolved spectroscopy gives images transverse to the muscle.

Effects of exercise training on systo-diastolic ventricular dysfunction in patients with hypertension: an echocardiographic study with tissue velocity and strain imaging evaluation.

PubMed

Leggio, Massimo; Mazza, Andrea; Cruciani, Giancarlo; Sgorbini, Luca; Pugliese, Marco; Bendini, Maria Grazia; Severi, Paolo; Jesi, Anna Patrizia

2014-07-01

There is a lack of detailed data regarding the effect of exercise training in pharmacologically treated hypertensive patients. Therefore, the aim of this study was to evaluate the effects of exercise training on left and right ventricular morphologic and functional parameters by means of conventional echocardiography and sensitive new echocardiographic techniques including tissue Doppler velocity and strain imaging, that were performed in pharmacologically treated hypertensive patients at baseline and at the end of a specific exercise training protocol for primary prevention of cardiovascular disease. We selected 116 pharmacologically treated hypertensive patients who completed the exercise training protocol. All patients underwent a clinical history and examination; transthoracic echocardiography and exercise testing were performed at baseline and at the end of the exercise training protocol. Conventional echocardiography revealed a mild degree of diastolic dysfunction without significant differences or variations from baseline to the end of the exercise training protocol. In contrast, tissue Doppler velocity and strain imaging measurements demonstrated and highlighted the positive influence of exercise training: for both left and right ventricle myocardial early peak diastolic velocities (Em), the ratio of myocardial early-late peak diastolic velocity (Em/Am), myocardial peak systolic velocities (Sm) and peak strain and strain rate values significantly increased at the end of the exercise training protocol, suggesting a relationship between exercise capacity and both left and right ventricular systo-diastolic function. Our study, by means of newer more sensitive echocardiographic techniques, clearly demonstrated the positive impact of exercise training on both left and right ventricular systo-diastolic function, in terms of adjunctive subclinical improvement, in pharmacologically treated hypertensive patients.

40 CFR 401.15 - Toxic pollutants.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Mercury and compounds 46. Naphthalene 47. Nickel and compounds 48. Nitrobenzene 49. Nitrophenols.... Tetrachloroethylene 60. Thallium and compounds 61. Toluene 62. Toxaphene 1 63. Trichloroethylene 64. Vinyl chloride 65...

40 CFR 401.15 - Toxic pollutants.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... Mercury and compounds 46. Naphthalene 47. Nickel and compounds 48. Nitrobenzene 49. Nitrophenols.... Tetrachloroethylene 60. Thallium and compounds 61. Toluene 62. Toxaphene 1 63. Trichloroethylene 64. Vinyl chloride 65...

40 CFR 401.15 - Toxic pollutants.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... Mercury and compounds 46. Naphthalene 47. Nickel and compounds 48. Nitrobenzene 49. Nitrophenols.... Tetrachloroethylene 60. Thallium and compounds 61. Toluene 62. Toxaphene 1 63. Trichloroethylene 64. Vinyl chloride 65...

Tabun

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Sarin

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Arsine

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Strychnine

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Phosgene

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Abrin

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Soman

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Ricin

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Exercise motives and positive body image in physically active college women and men: Exploring an expanded acceptance model of intuitive eating.

PubMed

Tylka, Tracy L; Homan, Kristin J

2015-09-01

The acceptance model of intuitive eating posits that body acceptance by others facilitates body appreciation and internal body orientation, which contribute to intuitive eating. Two domains of exercise motives (functional and appearance) may also be linked to these variables, and thus were integrated into the model. The model fit the data well for 406 physically active U.S. college students, although some pathways were stronger for women. Body acceptance by others directly contributed to higher functional exercise motives and indirectly contributed to lower appearance exercise motives through higher internal body orientation. Functional exercise motives positively, and appearance exercise motives inversely, contributed to body appreciation. Whereas body appreciation positively, and appearance exercise motives inversely, contributed to intuitive eating for women, only the latter association was evident for men. To benefit positive body image and intuitive eating, efforts should encourage body acceptance by others and emphasize functional and de-emphasize appearance exercise motives. Copyright © 2015 Elsevier Ltd. All rights reserved.

Movement - uncoordinated

MedlinePlus

... thallium, and lead Solvents such as toluene or carbon tetrachloride Other causes include: Certain cancers, in which ... system and muscles, paying careful attention to walking, balance, and coordination of pointing with fingers and toes. ...

Nitrogen Mustards

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Sodium Azide

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Sulfur Mustard

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Pneumonic Plague

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

Recent Progress in Thallium Bromide Gamma-Ray Spectrometer Development

NASA Astrophysics Data System (ADS)

Kim, Hadong; Kargar, Alireza; Cirignano, Leonard; Churilov, Alexei; Ciampi, Guido; Higgins, William; Olschner, Fred; Shah, Kanai

2012-02-01

In recent years, progress in processing and crystal growth methods have led to a significant increase in the mobility-lifetime product of electrons in thallium bromide (TlBr). This has enabled single carrier collection devices with thickness greater than 1-cm to be fabricated. In this paper we report on our latest results from pixellated devices with depth correction as well as our initial results with Frisch collar devices. After applying depth corrections, energy resolution of approximately 2% (FWHM at 662 keV) was obtained from a 13-mm thick TlBr array operated at -18°C and under continuous bias and irradiation for more than one month. Energy resolution of 2.4% was obtained at room temperature with an 8.4-mm thick TlBr Frisch collar device.

USING ANIMATIONS TO TALK ABOUT EARTH SCIENCE - an Example on Emerging Pollutants

NASA Astrophysics Data System (ADS)

Schneider, Simon; Ospina-Alvarez, Natalia

2017-04-01

Teaching and Learning material for school and out-of-school educational environments such as museums, school-labs, geo-parks and others is crucial to implement Earth and Space science issues in modern science classes. To reach the primary audience, which consists not only of children and pupils but has to target teaching professionals from schools as well as from out-of-school venues, multimedia applications with accompanying teaching materials are advisable. GeoEd (http://geoeducation.de/) started to develop such material in a pilot project that aims on the analysis of emerging pollutants. Thallium is used for various high-technology products (optics, electronics or even medicine). It is only used in small amounts, but because of its unique characteristics it has become an important raw material in modern consumer electronics. Nevertheless, Thallium is toxic. Since Thallium is also a by-product of mining processes and is transferred into natural water and soil supplies, it is important to identify thallium concentrations in food plants and water respectively. To foster public engagement, a holistic approach to communicate systemic background information is crucial. Therefore, this GeoEd-project will introduce a commonly underrepresented perspective to decision making processes in political strategies related to urbanization, resource and land management, and other topics. The lack of specialized knowledge which enables the public to better assess political decisions in reference to the implications on their daily life and the environment (e.g. recycling programs, establishment of permitted limit concentrations of substances, composition of building materials in schools, etc.) will be addressed by training the first link (teachers) in the chain of dissemination of knowledge. On a secondary level, the project seeks to sensitize the general public (last link in the chain) to better identify environmental process and interdependencies in their natural and urban environment. The outreach project, related to the ISPETI-project funded by AXA Research Fund, will highlight the importance of sampling and extraction methods to identify environmental risks related to thallium. Modern technologies to determine the concentration of toxic materials in soil, water and food might become an integral part of environmental policy for example in mining regions with growing population and an increased demand for land, soil and water. Schools, out-of-school projects, museums and other educational venues provide exceptional opportunities to initiate a dialogue between scientists, the public and decision makers. Parallel to focussing on thallium, the project will also highlight other materials which also present a possible environmental risks, such as antimony, arsenic and others. This presentation will show, how GeoEd approached the development and dissemination of a most recent research topic. We will present, how a set of animation, printed information and workshops can implement a complex issue into learning environments. A special focus will be set on the implementation of the Open Educational resources (OER) concept that aims towards freely accessible, openly licensed documents and media that are useful for teaching, learning, and assessing as well as for research purposes. While there is an ongoing debate about the heterogeneity of OER initiatives on national and international levels, the core element of OER is undisputed. By implementing the OER concept to new initiatives and projects, educational material will be accessible without time-wise or spatial barriers. Acknowledgment: This project is supported by an Outreach Grant of AXA Research Fund (Paris, France).

"I just feel so guilty": The role of introjected regulation in linking appearance goals for exercise with women's body image.

PubMed

Hurst, Megan; Dittmar, Helga; Banerjee, Robin; Bond, Rod

2017-03-01

Appearance goals for exercise are consistently associated with negative body image, but research has yet to consider the processes that link these two variables. Self-determination theory offers one such process: introjected (guilt-based) regulation of exercise behavior. Study 1 investigated these relationships within a cross-sectional sample of female UK students (n=215, 17-30 years). Appearance goals were indirectly, negatively associated with body image due to links with introjected regulation. Study 2 experimentally tested this pathway, manipulating guilt relating to exercise and appearance goals independently and assessing post-test guilt and body anxiety (n=165, 18-27 years). The guilt manipulation significantly increased post-test feelings of guilt, and these increases were associated with increased post-test body anxiety, but only for participants in the guilt condition. The implications of these findings for self-determination theory and the importance of guilt for the body image literature are discussed. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Wakata exercises on the aRED

NASA Image and Video Library

2013-11-15

View of Koichi Wakata, Expedition 38 Flight Engineer (FE), exercising on the Advanced Resistive Exercise Device (aRED), in the Node 3. Photo was taken during Expedition 38. Image was released by astronaut on Twitter.

Evaluation of left ventricular performance during supine exercise by transoesophageal M-mode echocardiography in normal subjects.

PubMed Central

Matsumoto, M; Hanrath, P; Kremer, P; Tams, C; Langenstein, B A; Schlüter, M; Weiter, R; Bleifeld, W

1982-01-01

In order to evaluate left ventricular function during dynamic exercise transoesophageal M-mode recordings of the left ventricle were carried out with a newly developed transducer gastroscope system. Twelve healthy subjects performed a graded supine bicycle exercise test. Stable and good quality images of the left ventricle at rest and during exercise at different steps up to a maximum workload of 100 watts were obtained in all patients. Isotonic maximum exercise resulted in a significant increase in fractional shortening of the left ventricle, peak shortening rate, and peak lengthening rate of the left ventricular minor axis. Left ventricular end-diastolic dimension decreased significantly. With increasing workload the pressure rate product increased significantly. It is concluded that transoesophageal M-mode echocardiography is a useful method of evaluating left ventricular performance during dynamic exercise. Images PMID:7082515

Visual portrayals of obesity in health media: promoting exercise without perpetuating weight bias.

PubMed

Pearl, R L; Dovidio, J F; Puhl, R M

2015-08-01

Health education campaigns for preventing and reducing obesity often contain weight-stigmatizing visual content, which may have unintended negative health consequences. The goal of the present research was to identify non-stigmatizing visual content for health education materials that can promote exercise among people of diverse weight statuses. An online sample of 483 US women viewed: (i) a woman with obesity portrayed stereotypically; (ii) a woman with obesity exercising; (iii) a woman with obesity portrayed neutrally; or (iv) a lean woman exercising. Race of the models pictured was randomized (White or Black). Participants completed measures of weight bias and exercise behavior and attitudes, and provided information about their weight status. Analysis of covariance revealed that responses to stereotypical and exercise images varied by participant weight status. Across participants, neutral obesity portrayals elicited lower expressions of weight-biased attitudes and higher reports of exercise liking/comfort. Among non-overweight participants, images portraying women with obesity stereotypically or counter-stereotypically produced greater endorsement of negative stereotypes than control, lean images. No effects of model race were found. These findings suggest that the public responds differently to visual portrayals of obesity depending on weight status, and neutral portrayals may be an effective route toward promoting exercise without perpetuating stigma. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Bioterrorism Agents/Diseases

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

The association between physical activity and eating self-regulation in overweight and obese women.

PubMed

Carraça, Eliana V; Silva, Marlene N; Coutinho, Sílvia R; Vieira, Paulo N; Minderico, Cláudia S; Sardinha, Luís B; Teixeira, Pedro J

2013-01-01

Successful weight management relies heavily on eating and exercise behaviors. However, little is known about the association between both on a psychosocial level. This study examined the relationship between exercise and eating regulation by exploring the mediating effects of negative body image investment and depressive mood, and their stability through time. Analyses were conducted at two different moments (12 and 36 months), involving a sample of 221 overweight/obese women (age: 37.6 ± 7 years; BMI: 31.6 ± 4.1 kg/m(2)) that participated in a behavioral weight control intervention. Bivariate correlations and mediation analyses using Preacher & Hayes resampling procedures were conducted. At 12 months, negative body image investment was the only significant mediator of the exercise-eating relationship. This variable explained larger portions of the indirect effects of structured rather than lifestyle exercise on eating. At 36 months, negative investment and to a lesser extent depressive mood partially explained the exercise-eating association. Our findings suggest that, besides physiological effects of exercise, psychological mechanisms related to body image and mood also explain the role of physical activity as a 'gateway behavior' for improved eating regulation in overweight women. These effects appear to be stable and may help understand the key role of exercise in long-term weight management.

Thallium-rich rust scales in drinkable water distribution systems: A case study from northern Tuscany, Italy.

PubMed

Biagioni, Cristian; D'Orazio, Massimo; Lepore, Giovanni O; d'Acapito, Francesco; Vezzoni, Simone

2017-06-01

Following the detection of a severe thallium contamination of the drinkable water from the public distribution system of Valdicastello Carducci-Pietrasanta (northern Tuscany, Italy), and the identification of the source of contamination in the Molini di Sant'Anna spring (average Tl content≈15μgL -1 ), the replacement of the contaminated water with a virtually Tl-free one (Tl<0.10μgL -1 ) caused an increase in Tl concentration in the drinkable water. This suggested that the pipeline interior had become a secondary source of Tl contamination, promoting its mineralogical and geochemical study. Rust scales samples taken from several pipeline segments, as well as leaching products obtained from these samples, were investigated through scanning electron microscopy, X-ray fluorescence chemical analyses, inductively coupled plasma - mass spectrometry, X-ray diffraction, and X-ray absorption spectroscopy. Thallium-rich rust scales (up to 5.3wt% Tl) have been found only in pipeline samples taken downstream the water treatment plant, whereas the sample taken upstream contains much less Tl (~90μgg -1 ). The Tl-rich nature of such scales is related to the occurrence of nano- and micro-spherules of Tl 2 O 3 and less abundant nanocrystalline μm-sized encrustations of TlCl. Leaching experiments on Tl-rich rust scales indicate that a fraction of the available Tl is easily dissolved in tap water; X-ray absorption spectroscopy suggests that monovalent thallium occurs in water equilibrated with the rust scales, probably related to the dissolution of TlCl encrustations. Therefore, Tl dissolved as Tl + only in the water from the Molini di Sant'Anna spring was partially removed through oxidative precipitation of Tl 2 O 3 and precipitation of TlCl. This highlights the critical role played by the addition of chlorine-based oxidants in water treatment plants that could favour the deposition of Tl-rich coatings within the pipelines, giving rise to unexpected secondary sources of contamination. Copyright © 2017 Elsevier B.V. All rights reserved.

Environmental Toxin Screening Using Human-Derived 3D Bioengineered Liver and Cardiac Organoids.

PubMed

Forsythe, Steven D; Devarasetty, Mahesh; Shupe, Thomas; Bishop, Colin; Atala, Anthony; Soker, Shay; Skardal, Aleksander

2018-01-01

Environmental toxins, such as lead and other heavy metals, pesticides, and other compounds, represent a significant health concern within the USA and around the world. Even in the twenty-first century, a plethora of cities and towns in the U.S. have suffered from exposures to lead in drinking water or other heavy metals in food or the earth, while there is a high possibility of further places to suffer such exposures in the near future. We employed bioengineered 3D human liver and cardiac organoids to screen a panel of environmental toxins (lead, mercury, thallium, and glyphosate), and charted the response of the organoids to these compounds. Liver and cardiac organoids were exposed to lead (10 µM-10 mM), mercury (200 nM-200 µM), thallium (10 nM-10 µM), or glyphosate (25 µM-25 mM) for a duration of 48 h. The impacts of toxin exposure were then assessed by LIVE/DEAD viability and cytotoxicity staining, measuring ATP activity and determining IC50 values, and determining changes in cardiac organoid beating activity. As expected, all of the toxins induced toxicity in the organoids. Both ATP and LIVE/DEAD assays showed toxicity in both liver and cardiac organoids. In particular, thallium was the most toxic, with IC50 values of 13.5 and 1.35 µM in liver and cardiac organoids, respectively. Conversely, glyphosate was the least toxic of the four compounds, with IC50 values of 10.53 and 10.85 mM in liver and cardiac organoids, respectively. Additionally, toxins had a negative influence on cardiac organoid beating activity as well. Thallium resulting in the most significant decreases in beating rate, followed by mercury, then glyphosate, and finally, lead. These results suggest that the 3D organoids have significant utility to be deployed in additional toxicity screening applications, and future development of treatments to mitigate exposures. 3D organoids have significant utility to be deployed in additional toxicity screening applications, such as future development of treatments to mitigate exposures, drug screening, and environmental toxin detection.

Evaluation of muscle injury using magnetic resonance imaging

NASA Technical Reports Server (NTRS)

LeBlanc, A. D.; Jaweed, M.; Evans, H.

1993-01-01

The objective of this study was to investigate spin echo T2 relaxation time changes in thigh muscles after intense eccentric exercise in healthy men. Spin echo and calculated T2 relaxation time images of the thighs were obtained on several occasions after exercise of one limb; the contralateral limb served as control. Muscle damage was verified by elevated levels of serum creatine kinase (CK). Thirty percent of the time no exercise effect was discernible on the magnetic resonance (MR) images. In all positive MR images (70%) the semitendinosus muscle was positive, while the biceps femoris, short head, and gracilis muscles were also positive in 50% and 25% of the total cases, respectively. The peak T2 relaxation time and serum CK were correlated (r = 0.94, p<0.01); temporal changes in muscle T2 relaxation time and serum CK were similar, although T2 relaxation time remained positive after serum CK returned to background levels. We conclude that magnetic resonance imaging can serve as a useful tool in the evaluation of eccentric exercise muscle damage by providing a quantitative indicator of damage and its resolution as well as the specific areas and muscles.

The effects of aerobic exercise on psychosocial functioning of adolescents who are overweight or obese.

PubMed

Goldfield, Gary S; Adamo, Kristi B; Rutherford, Jane; Murray, Marisa

2012-01-01

To evaluate effects of stationary cycling to music versus interactive video game cycling on psychosocial functioning in obese adolescents. 30 obese adolescents aged 12-17 years were randomized to twice weekly laboratory-based sessions of stationary cycling to music or interactive video game cycling for a 10-week trial. Participant's self-reported measures of scholastic competence, social competence, athletic competence, body image, and self-esteem were obtained. Aerobic fitness and body composition were directly measured. Although no differences emerged between exercise groups over time, when collapsed across exercise modality, significant pre-post improvements were found for body image, perceived scholastic competence and social competence. Changes in aerobic fitness, but not body composition, were positively associated with psychosocial functioning. Aerobic exercise was associated with improvements in body image, perceived academic performance, and social competence in obese adolescents, and these psychological benefits were related to improved aerobic fitness but not changes in body composition.

Frequently Asked Questions (FAQ) about Plague

MedlinePlus

... Cyanogen chloride (CK) Digitalis Case Definition: Digitalis Poisoning Ethylene glycol Fentanyls and other opioids Case Definition: Opioids ( ... Thallium Toxic alcohols Case Definition: Toxic Alcohol Poisoning Ethylene glycol Trichothecene Case Definition: Trichothecene Mycotoxin Poisoning Unidentified ...

40 CFR Appendix I to Part 258 - Constituents for Detection Monitoring

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Cobalt (Total) (8) Copper (Total) (9) Lead (Total) (10) Nickel (Total) (11) Selenium (Total) (12) Silver (Total) (13) Thallium (Total) (14) Vanadium (Total) (15) Zinc (Total) Organic Constituents: (16) Acetone...

40 CFR Appendix I to Part 258 - Constituents for Detection Monitoring

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Cobalt (Total) (8) Copper (Total) (9) Lead (Total) (10) Nickel (Total) (11) Selenium (Total) (12) Silver (Total) (13) Thallium (Total) (14) Vanadium (Total) (15) Zinc (Total) Organic Constituents: (16) Acetone...

Cardiac involvement in facio-scapulo-humeral muscular dystrophy: a family study using Thallium-201 single-photon-emission-computed tomography.

PubMed

Faustmann, P M; Farahati, J; Rupilius, B; Dux, R; Koch, M C; Reiners, C

1996-12-01

Fifteen persons from two consecutive generations of one family affected with facio-scapulo-humeral muscular dystrophy (FSHD) were clinically and neurophysiologically examined. Diagnostic muscle biopsies were obtained from two members. Linkage analysis showed that all four affected members of the family inherit the same 4q35 haplotype giving a lod score of z = +1.44. Six family members were examined by ECG at rest and under stress, by two-dimensional echocardiography, and by cardiac Thallium-201 single-photon-emission computed tomography (Tl-201-SPECT) under dobutamine stress and at rest. Abnormal reduced Tl-201 uptake in cardiac SPECT was only found in the affected members of the family. Therefore we suggest that cardiac Tl-201-SPECT abnormalities in FSHD reflect cardiomyogenic changes in this type of muscular disease.

Electronic structure and optical properties of CsI, CsI(Ag), and CsI(Tl)

NASA Astrophysics Data System (ADS)

Zhang, Zheng; Zhao, Qiang; Li, Yang; Ouyang, Xiao-Ping

2016-05-01

The band structure, electronic density of states and optical properties of CsI and of CsI doped with silver or thallium are studied by using a first-principles calculation based on density functional theory (DFT). The exchange and the correlation potentials among the electrons are described by using the generalized gradient approximation (GGA). The results of our study show that the electronic structure changes somewhat when CsI is doped with silver or thallium. The band gaps of CsI(Ag) and CsI(Tl) are smaller than that of CsI, and the width of the conduction band of CsI is increased when CsI is doped with thallium or silver. Two peaks located in the conduction band of CsI(Ag) and CsI(Tl) are observed from their electronic densities of states. The absorption coefficients of CsI, CsI(Ag), and CsI(Tl) are zero when their photon energies are below 3.5 eV, 1.5 eV, and 3.1 eV, respectively. The results show that doping can improve the detection performance of CsI scintillators. Our study can explain why doping can improve the detection performance from a theoretical point of view. The results of our research provide both theoretical support for the luminescent mechanisms at play in scintillator materials when they are exposed to radiation and a reference for CsI doping from the point of view of the electronic structure.

Potentials of acousto-optical spectrum analysis on a basis of a novel algorithm of the collinear wave heterodyning in a large-aperture KRS-5 crystalline cell

NASA Astrophysics Data System (ADS)

Shcherbakov, Alexandre S.; Maximov, Jewgenij; Bliznetsov, Alexej M.; Sanchez Perez, Karla J.

2011-03-01

The technique under proposal for a precise spectrum analysis within an algorithm of the collinear wave heterodyning implies a two-stage integrated processing, namely, the wave heterodyning of a signal in a square-law nonlinear medium and then the optical processing in the same solid state cell. The technical advantage of this approach lies in providing a direct multichannel parallel processing of ultra-high-frequency radio-wave signals with essentially improved frequency resolution. This technique imposes specific requirements on the cell's material. We focus our attention on the solid solutions of thallium chalcogenides and take the TlBr-TlI (thallium bromine-thallium iodine) solution, which forms KRS-5 cubic-symmetry crystals with the mass-ratio 58% of TlBr to 42% of TlI. Analysis shows that the acousto-optical cell made of a KRS-5 crystal oriented along the [111]-axis and the corresponding longitudinal elastic mode for producing the dynamic diffractive grating can be exploited. With the acoustic velocity of about 1.92 × 105 cm/s and attenuation of ~10 dB/(cm GHz2), a similar cell is capable of providing an optical aperture of ~5.0 cm and one of the highest figures of acousto-optical merit in solid states in the visible range. Such a cell is rather desirable for the application to direct 5000-channel parallel spectrum analysis with an improved up to 10-5 relative frequency resolution.

Study of acute biochemical effects of thallium toxicity in mouse urine by NMR spectroscopy.

PubMed

Tyagi, Ritu; Rana, Poonam; Khan, Ahmad Raza; Bhatnagar, Deepak; Devi, M Memita; Chaturvedi, Shubhra; Tripathi, Rajendra P; Khushu, Subash

2011-10-01

Thallium (Tl) is a toxic heavy metal and its exposure to the human body causes physiological and biochemical changes due to its interference with potassium-dependent biological reactions. A high-resolution (1)H NMR spectroscopy based metabonomic approach has been applied for investigating acute biochemical effects caused by thallium sulfate (Tl(2)SO(4)). Male strain A mice were divided in three groups and received three doses of Tl(2)SO(4) (5, 10 and 20 mg kg(-1) b.w., i.p.). Urine samples collected at 3, 24, 72 and 96 h post-dose time points were analyzed by (1)H NMR spectroscopy. NMR spectral data were processed and analyzed using principal components analysis to represent biochemical variations induced by Tl(2)SO(4). Results showed Tl-exposed mice urine to have distinct metabonomic phenotypes and revealed dose- and time-dependent clustering of treated groups. The metabolic signature of urine analysis from Tl(2)SO(4)-treated animals exhibited an increase in the levels of creatinine, taurine, hippurate and β-hydroxybutyrate along with a decrease in energy metabolites trimethylamine and choline. These findings revealed Tl-induced disturbed gut flora, membrane metabolite, energy and protein metabolism, representing physiological dysfunction of vital organs. The present study indicates the great potential of NMR-based metabonomics in mapping metabolic response for toxicology, which could ultimately lead to identification of potential markers for Tl toxicity. Copyright © 2011 John Wiley & Sons, Ltd.

Terbinafine is a novel and selective activator of the two-pore domain potassium channel TASK3.

PubMed

Wright, Paul D; Veale, Emma L; McCoull, David; Tickle, David C; Large, Jonathan M; Ococks, Emma; Gothard, Gemma; Kettleborough, Catherine; Mathie, Alistair; Jerman, Jeffrey

2017-11-04

Two-pore domain potassium channels (K2Ps) are characterized by their four transmembrane domain and two-pore topology. They carry background (or leak) potassium current in a variety of cell types. Despite a number of important roles there is currently a lack of pharmacological tools with which to further probe K2P function. We have developed a cell-based thallium flux assay, using baculovirus delivered TASK3 (TWIK-related acid-sensitive K + channel 3, KCNK9, K2P9.1) with the aim of identifying novel, selective TASK3 activators. After screening a library of 1000 compounds, including drug-like and FDA approved molecules, we identified Terbinafine as an activator of TASK3. In a thallium flux assay a pEC50 of 6.2 ( ±0.12) was observed. When Terbinafine was screened against TASK2, TREK2, THIK1, TWIK1 and TRESK no activation was observed in thallium flux assays. Several analogues of Terbinafine were also purchased and structure activity relationships examined. To confirm Terbinafine's activation of TASK3 whole cell patch clamp electrophysiology was carried out and clear potentiation observed in both the wild type channel and the pathophysiological, Birk-Barel syndrome associated, G236R TASK3 mutant. No activity at TASK1 was observed in electrophysiology studies. In conclusion, we have identified the first selective activator of the two-pore domain potassium channel TASK3. Copyright © 2017 Elsevier Inc. All rights reserved.

[Intracoronary, human autologous stem cell transplantation for myocardial regeneration following myocardial infarction].

PubMed

Strauer, B E; Brehm, M; Zeus, T; Gattermann, N; Hernandez, A; Sorg, R V; Kögler, G; Wernet, P

2001-08-24

The regenerative potential of human autologous adult stem cells on myocardial regeneration and neovascularisation after myocardial infarction may contribute to healing of the infarction area. But no clinical application has previously been reported. We here describe for the first time the results of this method applied in a patient who had sustained an acute myocardial infarction. 14 hours after the onset of left precordial pain a 46-year-old man was admitted to our hospital for interventional diagnosis and treatment. Coronary angiography demonstrated occlusion of the anterior descending branch of the left coronary artery with transmural infarction. This was treated by percutaneous transluminal catheter angioplasty and stent placement. Mononuclear bone marrow cells of the patient were prepared and 6 days after infaction 1,2 infinity 107 cells were transplanted at low pressure via a percutaneous transluminal catheter placed in the infarct-related artery. Before and 10 weeks after this procedure left ventricular function, infarct size, ventricular geometry and myocardial perfusion were measured by (201)thallium SPECT both at rest and on exercise, together with bull's-eye analysis, dobutamine stress echocardiography, right heart catheterisation and radionuclide ventriculography. At 10 weeks after the stem cell transplantation the transmural infarct area had been reduced from 24.6 % to 15.7 % of left ventricular circumference, while ejection fraction, cardiac index and stroke volume had increased by 20-30 %. On exercise the end diastolic volume had decreased by 30 % and there was a comparable fall in left ventricular filling pressure (mean pulmonary capillary pressure). These results for the first time demonstrate that selective intracoronary transplantation of human autologous adult stem cells is possible under clinical conditions and that it can lead to regeneration of the myocardial scar after transmural infarction. The therapeutic effects may be ascribed to stem cell-associated myocardial regeneration and neovascularisation.

My mother told me: the roles of maternal messages, body image, and disordered eating in maladaptive exercise.

PubMed

Lease, Haidee J; Doley, Joanna R; Bond, Malcolm J

2016-09-01

The current study examined the relevance of familial environment (negative maternal messages) to the phenomenon of maladaptive (obligatory) exercise, defined as exercise fixation. Weight/shape concerns and exercise frequency were examined as potential mediators, evaluated both with and without eating disorder symptoms as a covariate. Self-report data comprising sociodemographic details and measures of parental weight messages, body image, obligatory exercise, and disordered eating symptoms were completed by 298 young female attendees of health and fitness centres. The frequency of negative maternal messages demonstrated significant associations with all of weight/shape concerns, exercise frequency, exercise fixation, and eating disorder symptoms. In the initial model, partial mediation of maternal messages to exercise fixation was evident as negative maternal messages continued to have a direct effect on exercise fixation. In the second model, with the inclusion of eating disorder symptoms as a covariate, this direct effect was maintained while mediation was no longer evident. The data provide further support for the association between disordered eating symptoms and maladaptive exercise, as defined by exercise fixation. Nevertheless, the importance of negative maternal messages as a key environmental enabler of exercise fixation has been demonstrated, even after the effects of weight/shape concerns and exercise frequency were accounted for. Clinically, addressing weight-related talk in the family home may reduce the incidence of problematic cognitions and behaviours associated with both maladaptive exercise and disordered eating symptoms.

Comparison of treadmill exercise stress cardiac MRI to stress echocardiography in healthy volunteers for adequacy of left ventricular endocardial wall visualization: A pilot study

PubMed Central

Thavendiranathan, Paaladinesh; Dickerson, Jennifer A.; Scandling, Debbie; Balasubramanian, Vijay; Pennell, Michael L.; Hinton, Alice; Raman, Subha V.; Simonetti, Orlando P.

2013-01-01

Purpose To compare exercise stress cardiac magnetic resonance (cardiac MR) to echocardiography in healthy volunteers with respect to adequacy of endocardial visualization and confidence of stress study interpretation. Materials and Methods 28 healthy volunteers (aged 28 ± 11 years, 15 males) underwent exercise stress echo and cardiac MR one week apart assigned randomly to one test first. Stress cardiac MR was performed using an MRI-compatible treadmill; stress echo was performed as per routine protocol. Cardiac MR and echo images were independently reviewed and scored for adequacy of endocardial visualization and confidence in interpretation of the stress study. Results Heart rate at the time of imaging was similar between the studies. Average time from cessation of exercise to start of imaging (21 vs. 31 seconds, p<0.001) and time to acquire stress images (20 vs. 51 seconds, p<0.001) was shorter for cardiac MR. The number of myocardial segments adequately visualized was significantly higher by cardiac MR at rest (99.8% versus 96.4%, p=0.002) and stress (99.8% versus 94.1%, p=0.001). The proportion of subjects in whom there was high confidence in the interpretation was higher for cardiac MR than echo (96% vs 60%, p=0.005). Conclusion Exercise stress cardiac MR to assess peak exercise wall motion is feasible and can be performed at least as rapidly as stress echo. PMID:24123562

Printable organometallic perovskite enables large-area, low-dose X-ray imaging

NASA Astrophysics Data System (ADS)

Kim, Yong Churl; Kim, Kwang Hee; Son, Dae-Yong; Jeong, Dong-Nyuk; Seo, Ja-Young; Choi, Yeong Suk; Han, In Taek; Lee, Sang Yoon; Park, Nam-Gyu

2017-10-01

Medical X-ray imaging procedures require digital flat detectors operating at low doses to reduce radiation health risks. Solution-processed organic-inorganic hybrid perovskites have characteristics that make them good candidates for the photoconductive layer of such sensitive detectors. However, such detectors have not yet been built on thin-film transistor arrays because it has been difficult to prepare thick perovskite films (more than a few hundred micrometres) over large areas (a detector is typically 50 centimetres by 50 centimetres). We report here an all-solution-based (in contrast to conventional vacuum processing) synthetic route to producing printable polycrystalline perovskites with sharply faceted large grains having morphologies and optoelectronic properties comparable to those of single crystals. High sensitivities of up to 11 microcoulombs per air KERMA of milligray per square centimetre (μC mGyair-1 cm-2) are achieved under irradiation with a 100-kilovolt bremsstrahlung source, which are at least one order of magnitude higher than the sensitivities achieved with currently used amorphous selenium or thallium-doped cesium iodide detectors. We demonstrate X-ray imaging in a conventional thin-film transistor substrate by embedding an 830-micrometre-thick perovskite film and an additional two interlayers of polymer/perovskite composites to provide conformal interfaces between perovskite films and electrodes that control dark currents and temporal charge carrier transportation. Such an all-solution-based perovskite detector could enable low-dose X-ray imaging, and could also be used in photoconductive devices for radiation imaging, sensing and energy harvesting.

Printable organometallic perovskite enables large-area, low-dose X-ray imaging.

PubMed

Kim, Yong Churl; Kim, Kwang Hee; Son, Dae-Yong; Jeong, Dong-Nyuk; Seo, Ja-Young; Choi, Yeong Suk; Han, In Taek; Lee, Sang Yoon; Park, Nam-Gyu

2017-10-04

Medical X-ray imaging procedures require digital flat detectors operating at low doses to reduce radiation health risks. Solution-processed organic-inorganic hybrid perovskites have characteristics that make them good candidates for the photoconductive layer of such sensitive detectors. However, such detectors have not yet been built on thin-film transistor arrays because it has been difficult to prepare thick perovskite films (more than a few hundred micrometres) over large areas (a detector is typically 50 centimetres by 50 centimetres). We report here an all-solution-based (in contrast to conventional vacuum processing) synthetic route to producing printable polycrystalline perovskites with sharply faceted large grains having morphologies and optoelectronic properties comparable to those of single crystals. High sensitivities of up to 11 microcoulombs per air KERMA of milligray per square centimetre (μC mGy air -1 cm -2 ) are achieved under irradiation with a 100-kilovolt bremsstrahlung source, which are at least one order of magnitude higher than the sensitivities achieved with currently used amorphous selenium or thallium-doped cesium iodide detectors. We demonstrate X-ray imaging in a conventional thin-film transistor substrate by embedding an 830-micrometre-thick perovskite film and an additional two interlayers of polymer/perovskite composites to provide conformal interfaces between perovskite films and electrodes that control dark currents and temporal charge carrier transportation. Such an all-solution-based perovskite detector could enable low-dose X-ray imaging, and could also be used in photoconductive devices for radiation imaging, sensing and energy harvesting.

A Controlled Intervention to Promote a Healthy Body Image, Reduce Eating Disorder Risk and Prevent Excessive Exercise among Trainee Health Education and Physical Education Teachers

ERIC Educational Resources Information Center

Yager, Zali; O'Dea, Jennifer

2010-01-01

This study examined the impact of two interventions on body image, eating disorder risk and excessive exercise among 170 (65% female) trainee health education and physical education (HE & PE) teachers of mean (standard deviation) age 21.6 (2.3) who were considered an "at-risk" population for poor body image and eating disorders. In the first year…

The Association between Physical Activity and Eating Self-Regulation in Overweight and Obese Women

PubMed Central

Carraça, Eliana V.; Silva, Marlene N.; Coutinho, Sílvia R.; Vieira, Paulo N.; Minderico, Cláudia S.; Sardinha, Luís B.; Teixeira, Pedro J.

2013-01-01

Objective Successful weight management relies heavily on eating and exercise behaviors. However, little is known about the association between both on a psychosocial level. This study examined the relationship between exercise and eating regulation by exploring the mediating effects of negative body image investment and depressive mood, and their stability through time. Methods Analyses were conducted at two different moments (12 and 36 months), involving a sample of 221 overweight/obese women (age: 37.6 ± 7 years; BMI: 31.6 ± 4.1 kg/m2) that participated in a behavioral weight control intervention. Bivariate correlations and mediation analyses using Preacher & Hayes resampling procedures were conducted. Results At 12 months, negative body image investment was the only significant mediator of the exercise-eating relationship. This variable explained larger portions of the indirect effects of structured rather than lifestyle exercise on eating. At 36 months, negative investment and to a lesser extent depressive mood partially explained the exercise-eating association. Conclusions Our findings suggest that, besides physiological effects of exercise, psychological mechanisms related to body image and mood also explain the role of physical activity as a ‘gateway behavior’ for improved eating regulation in overweight women. These effects appear to be stable and may help understand the key role of exercise in long-term weight management. PMID:24217426

Acute exercise modulates cigarette cravings and brain activation in response to smoking-related images: an fMRI study.

PubMed

Janse Van Rensburg, Kate; Taylor, Adrian; Hodgson, Tim; Benattayallah, Abdelmalek

2009-04-01

Substances of misuse (such as nicotine) are associated with increases in activation within the mesocorticolimbic brain system, a system thought to mediate the rewarding effects of drugs of abuse. Pharmacological treatments have been designed to reduce cigarette cravings during temporary abstinence. Exercise has been found to be an effective tool for controlling cigarette cravings. The objective of this study is to assess the effect of exercise on regional brain activation in response to smoking-related images during temporary nicotine abstinence. In a randomized crossover design, regular smokers (n = 10) undertook an exercise (10 min moderate-intensity stationary cycling) and control (passive seating for same duration) session, following 15 h of nicotine abstinence. Following treatments, participants entered a functional Magnetic Resonance Imaging (fMRI) scanner. Subjects viewed a random series of smoking and neutral images for 3 s, with an average inter-stimulus-interval (ISI) of 10 s. Self-reported cravings were assessed at baseline, mid-, and post-treatments. A significant interaction effect (time by group) was found, with self-reported cravings lower during and following exercise. During control scanning, significant activation was recorded in areas associated with reward (caudate nucleus), motivation (orbitofrontal cortex) and visuo-spatial attention (parietal lobe, parahippocampal, and fusiform gyrus). Post-exercise scanning showed hypo-activation in these areas with a concomitant shift of activation towards areas identified in the 'brain default mode' (Broadmanns Area 10). The study confirms previous evidence that a single session of exercise can reduce cigarette cravings, and for the first time provides evidence of a shift in regional activation in response to smoking cues.

Recent Research on Eating Disorders and Body Image Distortion among Aerobic Instructors and Exercise Participants.

ERIC Educational Resources Information Center

Moriarty, Dick; And Others

This document reviews the research linking excessive exercise with eating disorders. Seven steps are listed that an individual follows in going from someone who starts out using exercise and aerobic dance as a stress management technique or a hobby to becoming an exercise dependent individual with addictive behavior. Studies are reviewed, the…

40 CFR Appendix I to Part 258 - Constituents for Detection Monitoring

Code of Federal Regulations, 2012 CFR

2012-07-01

...) (8) Copper (Total) (9) Lead (Total) (10) Nickel (Total) (11) Selenium (Total) (12) Silver (Total) (13) Thallium (Total) (14) Vanadium (Total) (15) Zinc (Total) Organic Constituents: (16) Acetone 67-64-1 (17...

NMR spectroscopy of Group 13 metal ions: biologically relevant aspects.

PubMed

André, J P; Mäcke, H R

2003-12-01

In spite of the fact that Group 13 metal ions (Al(3+), Ga(3+), In(3+) and Tl(+/3+)) show no main biological role, they are NMR-active nuclides which can be used in magnetic resonance spectroscopy of biologically relevant systems. The fact that these metal ions are quadrupolar (with the exception of thallium) means that they are particularly sensitive to ligand type and coordination geometry. The line width of the NMR signals of their complexes shows a strong dependence on the symmetry of coordination, which constitutes an effective tool in the elucidation of structures. Here we report published NMR studies of this family of elements, applied to systems of biological importance. Special emphasis is given to binding studies of these cations to biological molecules, such as proteins, and to chelating agents of radiopharmaceutical interest. The possibility of in vivo NMR studies is also stressed, with extension to (27)Al-based MRI (magnetic resonance imaging) experiments.

A case of reversible dilated cardiomyopathy after alpha-interferon therapy in a patient with renal cell carcinoma.

PubMed

Kuwata, Akiko; Ohashi, Masuo; Sugiyama, Masaya; Ueda, Ryuzo; Dohi, Yasuaki

2002-12-01

A 47-year-old man with renal cell carcinoma underwent nephrectomy, and postoperative chemotherapy was performed with recombinant alpha-interferon. Five years later, he experienced dyspnea during physical exertion. An echocardiogram revealed dilatation and systolic dysfunction of the left ventricle, and thallium-201 myocardial scintigraphy showed diffuse heterogeneous perfusion. We diagnosed congestive heart failure because of cardiomyopathy induced by alpha-interferon therapy. Withdrawal of interferon therapy and the combination of an angiotensin-converting enzyme inhibitor, diuretics, and digitalis improved left ventricular systolic function. Furthermore, myocardial scintigraphy using [123I] beta-methyl-p-iodophenylpentadecanoic acid (123I-BMIPP) or [123 I]metaiodobenzylguanidine (123I-MIBG) revealed normal perfusion after the improvement of congestive heart failure. This is a rare case of interferon-induced cardiomyopathy that resulted in normal myocardial images in 123I-BMIPP and 123I-MIBG scintigrams after withdrawal of interferon therapy.

Assessing the Diet, Exercise, Body Image, and Weight of Adolescents: A Guide for Out-of-School Time Program Practitioners. Research-to-Results Brief. Publication #2007-06

ERIC Educational Resources Information Center

Martin, Laurie; Milot, Alyssa

2007-01-01

This brief discusses diet, exercise, body image, and weight and also provides information for practitioners on how to measure these factors among youth in their program. It summarizes (1) what it means to be overweight; (2) what are body image and eating disorders; (3) what to do if you suspect that someone in your program is suffering from an…

The effect of supine exercise on the distribution of regional pulmonary blood flow measured using proton MRI

PubMed Central

Hall, E. T.; Sá, R. C.; Holverda, S.; Arai, T. J.; Dubowitz, D. J.; Theilmann, R. J.; Prisk, G. K.

2013-01-01

The Zone model of pulmonary perfusion predicts that exercise reduces perfusion heterogeneity because increased vascular pressure redistributes flow to gravitationally nondependent lung, and causes dilation and recruitment of blood vessels. However, during exercise in animals, perfusion heterogeneity as measured by the relative dispersion (RD, SD/mean) is not significantly decreased. We evaluated the effect of exercise on pulmonary perfusion in six healthy supine humans using magnetic resonance imaging (MRI). Data were acquired at rest, while exercising (∼27% of maximal oxygen consumption) using a MRI-compatible ergometer, and in recovery. Images were acquired in most of the right lung in the sagittal plane at functional residual capacity, using a 1.5-T MR scanner equipped with a torso coil. Perfusion was measured using arterial spin labeling (ASL-FAIRER) and regional proton density using a fast multiecho gradient-echo sequence. Perfusion images were corrected for coil-based signal heterogeneity, large conduit vessels removed and quantified (in ml·min−1·ml−1) (perfusion), and also normalized for density and quantified (in ml·min−1·g−1) (density-normalized perfusion, DNP) accounting for tissue redistribution. DNP increased during exercise (11.1 ± 3.5 rest, 18.8 ± 2.3 exercise, 13.2 ± 2.2 recovery, ml·min−1·g−1, P < 0.0001), and the increase was largest in nondependent lung (110 ± 61% increase in nondependent, 63 ± 35% in mid, 70 ± 33% in dependent, P < 0.005). The RD of perfusion decreased with exercise (0.93 ± 0.21 rest, 0.73 ± 0.13 exercise, 0.94 ± 0.18 recovery, P < 0.005). The RD of DNP showed a similar trend (0.82 ± 0.14 rest, 0.75 ± 0.09 exercise, 0.81 ± 0.10 recovery, P = 0.13). In conclusion, in contrast to animal studies, in supine humans, mild exercise decreased perfusion heterogeneity, consistent with Zone model predictions. PMID:24356515

Addition of right-sided and posterior precordial leads during stress testing.

PubMed

Shry, Eric A; Eckart, Robert E; Furgerson, James L; Stajduhar, Karl C; Krasuski, Richard A

2003-12-01

Exercise treadmill testing has limited sensitivity for the detection of coronary artery disease, frequently requiring the addition of imaging modalities to enhance the predictive value of the test. Recently, there has been interest in using nonstandard electrocardiographic (ECG) leads during exercise testing. We consecutively enrolled all patients undergoing exercise myocardial imaging with four additional leads recorded (V4R, V7, V8, and V9). The test characteristics of the 12-lead, the 15-lead (12-lead, V7, V8, V9), and the 16-lead (12-lead, V4R, V7, V8, V9) ECGs were compared with stress imaging in all patients. In the subset of patients who underwent angiography within 60 days of stress testing, these lead arrays were compared with the catheterization findings. There were 727 subjects who met entry criteria. The mean age was 58.5 +/- 12.3 years, and 366 (50.3%) were women. Pretest probability for disease was high in 241 (33.1%), intermediate in 347 (47.7%), and low in 139 (19.1%). A total of 166 subjects had an abnormal 12-lead ECG during exercise. The addition of 3 posterior leads to the standard 12-lead ECG resulted in 7 additional subjects having an abnormal electrocardiographic response to exercise. The addition of V4R resulted in only 1 additional patient having an abnormal ECG during exercise. The sensitivity of the ECG for detecting ischemia as determined by stress imaging was 36.6%, 39.2%, and 40.0% (P = NS) for the 12-lead, 15-lead, and 16-lead ECGs, respectively. In those with catheterization data (n = 123), the sensitivity for determining obstructive coronary artery disease was 43.5%, 45.2%, and 45.2% (P = NS) for the 12-lead, 15-lead, and 16-lead ECGs, respectively. The sensitivity of imaging modalities was 77.4% when compared with catheterization. In patients undergoing stress imaging studies, the addition of right-sided and posterior leads did not significantly increase the sensitivity of the ECG for the detection of myocardial ischemia. Additional leads should not be used to replace imaging modalities for the detection of coronary artery disease.

The relationship between physical activity and self-image and problem behaviour among adolescents.

PubMed

Kirkcaldy, B D; Shephard, R J; Siefen, R G

2002-11-01

Although there are a vast array of studies which have demonstrated the psychological and physical health benefits of regular aerobic exercise for adults, few studies have focussed on children and adolescents. The current study examined associations between the extent of participation in endurance sport, and self-report data on self-image, physical and psychological health and overall lifestyle in a large representative sample of German high-school students. Almost 1000 German adolescents (aged 14-18 years) were administered a comprehensive series of questionnaires aimed at assessing anxiety-depression, trait addiction, smoking and drinking behaviour, physical ill-health reports, and self-perception of self-image, parental acceptance and educational attainment. Regular practice of endurance exercise was related to a more favourable self-image. There was a strong association between participation in sports and the type of personality that tends to be resistant to drug and alcohol addiction. Physical exercise was further significantly related to scores for physical and psychological well-being. Adolescents who engaged regularly in physical activity were characterised by lower anxiety-depression scores, and displayed much less social behavioural inhibition than their less active counterparts. It is likely that discussion of recreational or exercise involvement may provide a useful point of entry for facilitating dialogue among adolescents about concerns relating to body image and self-esteem. In terms of psychotherapeutic applications, physical activity has many additional rewards for adolescents. It is probable that by promoting physical fitness, increased physical performance, lessening body mass and promoting a more favourable body shape and structure, exercise will provide more positive social feedback and recognition from peer groups, and this will subsequently lead to improvement in an individual's self-image.

Fact Sheet: Revised National Recommended Water Quality Criteria for the Protection of Human Health

EPA Pesticide Factsheets

2003 Revised National Recommended Ambient Water Quality Criteria for the Protection of Human Health. 15 Pollutants revised criteria will be published including, chlorobenzene, cyanide, endrin, ethylbenzene, lindane, thallium, toluene, and more.

9 CFR 113.28 - Detection of mycoplasma contamination.

Code of Federal Regulations, 2011 CFR

2011-01-01

... following: 1 percent tetrazolium chloride (ml) 5.5 1 percent thallium acetate (ml) 25 Penicillin (units) 500... solution 525,000 units of Penicillin. Dispense 10 ml aliquots into 60×15 mm disposable culture dishes or...

9 CFR 113.28 - Detection of mycoplasma contamination.

Code of Federal Regulations, 2013 CFR

2013-01-01

... following: 1 percent tetrazolium chloride (ml) 5.5 1 percent thallium acetate (ml) 25 Penicillin (units) 500... solution 525,000 units of Penicillin. Dispense 10 ml aliquots into 60×15 mm disposable culture dishes or...

9 CFR 113.28 - Detection of mycoplasma contamination.

Code of Federal Regulations, 2012 CFR

2012-01-01

... following: 1 percent tetrazolium chloride (ml) 5.5 1 percent thallium acetate (ml) 25 Penicillin (units) 500... solution 525,000 units of Penicillin. Dispense 10 ml aliquots into 60×15 mm disposable culture dishes or...

9 CFR 113.28 - Detection of mycoplasma contamination.

Code of Federal Regulations, 2014 CFR

2014-01-01

... following: 1 percent tetrazolium chloride (ml) 5.5 1 percent thallium acetate (ml) 25 Penicillin (units) 500... solution 525,000 units of Penicillin. Dispense 10 ml aliquots into 60×15 mm disposable culture dishes or...

Characterization of Stress in Thallium Bromide Devices

NASA Astrophysics Data System (ADS)

Datta, Amlan; Motakef, Shariar

2015-04-01

Thallium bromide (TlBr) is a wide bandgap, compound semiconductor with high gamma-ray stopping power and promising physical properties. Several surface modification techniques have been demonstrated to increase the lifetime of TlBr devices at room temperature. However, absence of reproducibility in the performance of TlBr detectors (even with low ionic conduction at -20°C) suggests presence of unexplored bulk phenomena. Stress in the TlBr crystal due to various intrinsic (e.g. grain boundaries and dislocations networks) in conjunction with external factors such as thermal, mechanical, and electrical loadings explains detector-to-detector variations. Photoelasticity and opto-electrical techniques were applied to visualize and qualitatively correlate the device performance with stress. Changes in stress patterns with variations in ambient temperature were clearly demonstrated. Electric field fluctuations in TlBr detectors with time were for the first time observed using the Pockels effect.

Photoluminescence properties of thallium-containing GeSe{sub 2} and GeSe{sub 3} vitreous semiconductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Babaev, A. A., E-mail: babaev-arif@mail.ru

2016-02-15

The photoluminescence properties of thallium-containing vitreous semiconductor systems with stoichiometric and nonstoichiometric compositions (GeSe{sub 2}){sub 1–x}Tl{sub x} and (GeSe{sub 3}){sub 1–x}Tl{sub x} (0 ⩽ x ⩽ 0.1) are studied at a temperature of T = 77 K. Intrinsic defects with negative correlation energy are responsible for the Gaussian shape of the photoluminescence spectra. It is established that an increase in x in the systems does not affect the shape of the spectrum, does not generate new emission bands, shifts the photoluminescence spectra to the region of low energies, reduces the intensity of radiation, and increases its half-width. Kinetics of themore » fatigue of photoluminescence is different for both systems and is characterized by one curve irrespective of Tl content in the systems.« less

Addition of a thallium vertex to empty and centered nine-atom deltahedral zintl ions of germanium and tin.

PubMed

Rios, Daniel; Gillett-Kunnath, Miriam M; Taylor, Jacob D; Oliver, Allen G; Sevov, Slavi C

2011-03-21

Nickel atoms were inserted into nine-atom deltahedral Zintl ions of E(9)(4-) (E = Ge, Sn) via reactions with Ni(cod)(2) (cod = cyclooctadiene), and [Ni@Sn(9)](3-) was structurally characterized. Both the empty and the Ni-centered clusters react with TlCp (Cp = cyclopentadienyl anion) and add a thallium vertex to form the deltahedral ten-atom closo-species [E(9)Tl](3-) and [Ni@E(9)Tl](3-), respectively. The structures of [Ge(9)Tl](3-) and [Ni@Sn(9)Tl](3-) showed that, as expected, the geometry of the ten-atom clusters is that of a bicapped square antiprism where the Tl-atom occupies one of the two capping vertices. This illustrates that centering a nine-atom cluster with a nickel atom does not change its reactivity toward TlCp. All compounds were characterized by electrospray mass spectrometry.

Development of Prototype HTS Components for Magnetic Suspension Applications

NASA Technical Reports Server (NTRS)

Haldar, P.; Hoehn, J., Jr.; Selvamanickam, V.; Farrell, R. A.; Balachandran, U.; Iyer, A. N.; Peterson, E.; Salazar, K.

1996-01-01

We have concentrated on developing prototype lengths of bismuth and thallium based silver sheathed superconductors by the powder-in-tube approach to fabricate high temperature superconducting (HTS) components for magnetic suspension applications. Long lengths of mono and multi filament tapes are presently being fabricated with critical current densities useful for maglev and many other applications. We have recently demonstrated the prototype manufacture of lengths exceeding 1 km of Bi-2223 multi filament conductor. Long lengths of thallium based multi-filament conductor have also been fabricated with practical levels of critical current density and improved field dependence behavior. Test coils and magnets have been built from these lengths and characterized over a range of temperatures and background fields to determine their performance. Work is in progress to develop, fabricate and test HTS windings that will be suitable for magnetic suspension, levitation and other electric power related applications.

Fractionation and Mobility of Thallium in Volcanic Ashes after Eruption of Eyjafjallajökull (2010) in Iceland.

PubMed

Karbowska, Bozena; Zembrzuski, Wlodzimierz

2016-07-01

Volcanic ash contains thallium (Tl), which is highly toxic to the biosphere. The aim of this study was to determine the Tl concentration in fractions of volcanic ash samples originating from the Eyjafjallajökull volcano. A sequential extraction scheme allowed for a study of element migration in the environment. Differential pulse anodic stripping voltammetry using a flow measuring system was selected as the analytical method to determine Tl content. The highest average content of Tl in volcanic ash was determined in the fraction entrapped in the aluminosilicate matrix (0.329 µg g(-1)), followed by the oxidizable fraction (0.173 µg g(-1)). The lowest content of Tl was found in the water soluble fraction (0.001 µg g(-1)); however, this fraction is important due to the fact that Tl redistribution among all the fractions occurs through the aqueous phase.

Preparation of TlBa2Ca2Cu3O9±δ high Tc thin films by laser ablation in combination with thermal evaporation of thallium oxide

NASA Astrophysics Data System (ADS)

Piehler, A.; Löw, R.; Betz, J.; Schönberger, R.; Renk, K. F.

1993-11-01

TlBa2Ca2Cu3O9±δ high Tc thin films were prepared on MgO <100> surfaces by a combination of laser ablation from a stoichiometric Ba2Ca2Cu3Ox target and the thermal evaporation of thallium oxide. X-ray diffraction measurements showed that the films consisted of predominantly c axis oriented TlBa2Ca2Cu3O9±δ, and scanning electron microscopy revealed that the surfaces had a flat, platelike morphology. The ac inductive measurements indicated that the onset of superconductivity occurred at 117 K with a transition width (10%-90%) of ˜3 K. Zero resistivity was reached at 120 K. The critical current density was ˜3×104 A/cm2 at 110 K.

The Health of Competitive Fitness Athletes

ClinicalTrials.gov

2018-03-28

Resting Metabolic Rate; Bone Mineral Density, Low, Susceptibility to; Body Image; Perfectionism; Depression; Eating Disorder; Exercise-Related Amenorrhea; Exercise Addiction; Binge Eating; Dietary Amenorrhea; Dietary Deficiency

Positron Emission Tomography for the Assessment of Myocardial Viability

PubMed Central

2005-01-01

Executive Summary Objective The objective was to update the 2001 systematic review conducted by the Institute For Clinical Evaluative Sciences (ICES) on the use of positron emission tomography (PET) in assessing myocardial viability. The update consisted of a review and analysis of the research evidence published since the 2001 ICES review to determine the effectiveness and cost-effectiveness of PET in detecting left ventricular (LV) viability and predicting patient outcomes after revascularization in comparison with other noninvasive techniques. Background Left Ventricular Viability Heart failure is a complex syndrome that impairs the contractile ability of the heart to maintain adequate blood circulation, resulting in poor functional capacity and increased risk of morbidity and mortality. It is the leading cause of hospitalization in elderly Canadians. In more than two-thirds of cases, heart failure is secondary to coronary heart disease. It has been shown that dysfunctional myocardium resulting from coronary heart disease (CAD) may recover contractile function (i.e. considered viable). Dysfunctional but viable myocardium may have been stunned by a brief episode of ischemia, followed by restoration of perfusion, and may regain function spontaneously. It is believed that repetitive stunning results in hibernating myocardium that will only regain contractile function upon revascularization. For people with CAD and severe LV dysfunction (left ventricular ejection fraction [LVEF] <35%) refractory to medical therapy, coronary artery bypass and heart transplantation are the only treatment options. The opportunity for a heart transplant is limited by scarcityof donor hearts. Coronary artery bypass in these patients is associated with high perioperative complications; however, there is evidence that revascularization in the presence of dysfunctional but viable myocardium is associated with survival benefits and lower rates of cardiac events. The assessment of left ventricular (LV) viability is, therefore, critical in deciding whether a patient with coronary artery disease and severe LV dysfunction should undergo revascularization, receive a heart transplant, or remain on medical therapy. Assessment of Left Ventricular Viability Techniques for assessing myocardial viability depend on the measurement of a specific characteristic of viable myocytes such as cell membrane integrity, preserved metabolism, mitochondria integrity, and preserved contractile reserve. In Ontario, single photon emission computed tomography (SPECT) using radioactive 201thallium is the most commonly used technique followed by dobutamine echocardiography. Newer techniques include SPECT using technetium tracers, cardiac magnetic resonance imaging, and PET, the subject of this review. Positron Emission Tomography PET is a nuclear imaging technique based on the metabolism of radioactive analogs of normal substrates such as glucose and water. The radiopharmaceutical used most frequently in myocardial viability assessment is F18 fluorodeoxyglucose (FDG), a glucose analog. The procedure involves the intravenous administration of FDG under controlled glycemic conditions, and imaging with a PET scanner. The images are reconstructed using computer software and analyzed visually or semi-quantitatively, often in conjunction with perfusion images. Dysfunctional but stunned myocardium is characterized by normal perfusion and normal FDG uptake; hibernating myocardium exhibits reduced perfusion and normal/enhanced FDG uptake (perfusion/metabolism mismatch), whereas scar tissue is characterized by reduction in both perfusion and FDG uptake (perfusion/metabolism match). Review Strategy The Medical Advisory Secretariat used a search strategy similar to that used in the 2001 ICES review to identify English language reports of health technology assessments and primary studies in selected databases, published from January 1, 2001 to April 20, 2005. Patients of interest were those with CAD and severe ventricular dysfunction being considered for revascularization that had undergone viability assessment using either PET and/or other noninvasive techniques. The outcomes of interest were diagnostic and predictive accuracy with respect to recovery of regional or global LV function, long-term survival and cardiac events, and quality of life. Other outcomes of interest were impact on treatment decision, adverse events, and cost-effectiveness ratios. Of 456 citations, 8 systematic reviews/meta-analyses and 37 reports on primary studies met the selection criteria. The reports were categorized using the Medical Advisory Secretariat levels of evidence system, and the quality of the reports was assessed using the criteria of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) developed by the Centre for Dissemination of Research (National Health Service, United Kingdom). Analysis of sensitivity, specificity, predictive values and likelihood ratios were conducted for all data as well as stratified by mean left ventricular ejection fraction (LVEF). There were no randomized controlled trials. The included studies compared PET with one or more other noninvasive viability tests on the same group of patients or examined the long-term outcomes of PET viability assessments. The quality assessment showed that about 50% or more of the studies had selection bias, interpreted tests without blinding, excluded uninterpretable segments in the analysis, or did not have clearly stated selection criteria. Data from the above studies were integrated with data from the 2001 ICES review for analysis and interpretation. Summary of Findings The evidence was derived from populations with moderate to severe ischemic LV dysfunction with an overall quality that ranges from moderate to low. PET appears to be a safe technique for assessing myocardial viability. CAD patients with moderate to severe ischemic LV dysfunction and residual viable myocardium had significantly lower 2-year mortality rate (3.2%) and higher event-free survival rates (92% at 3 years) when treated with revascularization than those who were not revascularized but were treated medically (16% mortality at 2-years and 48% 3-year event-free survival). A large meta-analysis and moderate quality studies of diagnostic accuracy consistently showed that compared to other noninvasive diagnostic tests such as thallium SPECT and echocardiography, FDG PET has: Higher sensitivity (median 90%, range 71%–100%) and better negative likelihood ratio (median 0.16, range 0–0.38; ideal <0.1) for predicting regional myocardial function recovery after revascularization. Specificity (median 73%, range 33%–91%) that is similar to other radionuclide imaging but lower than that of dobutamine echocardiography Less useful positive likelihood ratio (median 3.1, range 1.4 –9.2; ideal>10) for predicting segmental function recovery. Taking positive and negative likelihood ratios together suggests that FDG PET and dobutamine echocardiography may produce small but sometimes important changes in the probability of recovering regional wall motion after revascularization. Given its higher sensitivity, PET is less likely to produce false positive results in myocardial viability. PET, therefore, has the potential to identify some patients who might benefit from revascularization, but who would not have been identified as suitable candidates for revascularization using thallium SPECT or dobutamine echocardiography. PET appears to be superior to other nuclear imaging techniques including SPECT with 201thallium or technetium labelled tracers, although recent studies suggest that FDG SPECT may have comparable diagnostic accuracy as FDG PET for predicting regional and global LV function recovery. No firm conclusion can be reached about the incremental value of PET over other noninvasive techniques for predicting global function improvement or long-term outcomes in the most important target population (patients with severe ischemic LV dysfunction) due to lack of direct comparison. An Ontario-based economic analysis showed that in people with CAD and severe LV dysfunction and who were found to have no viable myocardium or indeterminate results by thallium SPECT, the use of PET as a follow-up assessment would likely result in lower cost and better 5-year survival compared to the use of thallium SPECT alone. The projected annual budget impact of adding PET under the above scenario was estimated to range from $1.5 million to $2.3 million. Conclusion In patients with severe LV dysfunction, that are deemed to have no viable myocardium or indeterminate results in assessments using other noninvasive tests, PET may have a role in further identifying patients who may benefit from revascularization. No firm conclusion can be drawn on the impact of PET viability assessment on long-term clinical outcomes in the most important target population (i.e. patients with severe LV dysfunction). PMID:23074467

Effects of different cooling treatments on water diffusion, microcirculation, and water content within exercised muscles: evaluation by magnetic resonance T2-weighted and diffusion-weighted imaging.

PubMed

Yanagisawa, Osamu; Takahashi, Hideyuki; Fukubayashi, Toru

2010-09-01

In this study, we determined the effects of different cooling treatments on exercised muscles. Seven adults underwent four post-exercise treatments (20-min ice-bag application, 60-min gel-pack application at 10 degrees C and 17 degrees C, and non-cooling treatment) with at least 1 week between treatments. Magnetic resonance diffusion- and T2-weighted images were obtained to calculate the apparent diffusion coefficients (apparent diffusion coefficient 1, which reflects intramuscular water diffusion and microcirculation, and apparent diffusion coefficient 2, which is approximately equal to the true diffusion coefficient that excludes as much of the effect of intramuscular microcirculation as possible) and the T2 values (intramuscular water content level) of the ankle dorsiflexors, respectively, before and after ankle dorsiflexion exercise and after post-exercise treatment. The T2 values increased significantly after exercise and returned to pre-exercise values after each treatment; no significant differences were observed among the four post-exercise treatments. Both apparent diffusion coefficients also increased significantly after exercise and decreased significantly after the three cooling treatments; no significant difference was detected among the three cooling treatments. Local cooling suppresses both water diffusion and microcirculation within exercised muscles. Moreover, although the treatment time was longer, adequate cooling effects could be achieved using the gel-pack applications at relatively mild cooling temperatures.

Thallium in flowering cabbage and lettuce: Potential health risks for local residents of the Pearl River Delta, South China.

PubMed

Yu, Huan-Yun; Chang, Chunying; Li, Fangbai; Wang, Qi; Chen, Manjia; Zhang, Jie

2018-06-08

Thallium (Tl), a rare metal, is universally present in the environment with high toxicity and accumulation. Thallium's behavior and fate require further study, especially in the Pearl River Delta (PRD), where severe Tl pollution incidents have occurred. One hundred two pairs of soil and flowering cabbage samples and 91 pairs of soil and lettuce samples were collected from typical farmland protection areas and vegetable bases across the PRD, South China. The contamination levels and spatial distributions of soil and vegetable (flowering cabbages and lettuces) Tl across the PRD were investigated. The relative contributions of soil properties to the bioavailability of Tl in vegetables were evaluated using random forest. Random forest is an accurate learning algorithm and is superior to conventional and correlation-based regression analyses. In addition, the health risks posed by Tl exposure via vegetable intake for residents of the PRD were assessed. The results indicated that rapidly available potassium (K) and total K in soil were the most important factors affecting Tl bioavailability, and the competitive effect of rapidly available K on vegetable Tl uptake was confirmed in this field study. Soil weathering also contributed substantially to Tl accumulation in the vegetables. In contrast, organic matter might not be a major factor affecting the mobility of Tl in most of the lettuce soils. Fe and manganese (Mn) oxides also contributed little to the bioavailability of Tl. A risk assessment suggested that the health risks for Tl exposure through flowering cabbage or lettuce intake were minimal. Copyright © 2018 Elsevier Ltd. All rights reserved.

Feasibility and safety of exercise stress testing using an anti-gravity treadmill with Tc-99m tetrofosmin single-photon emission computed tomography (SPECT) myocardial perfusion imaging: A pilot non-randomized controlled study.

PubMed

Daly, Patrick; Kayse, Regina; Rudick, Steven; Robbins, Nathan; Scheler, Jennifer; Harris, David; O'Donnell, Robert; Dwivedi, Alok K; Gerson, Myron C

2017-08-31

Exercise is the AHA/ACC guideline-recommended stress modality for myocardial perfusion imaging, but many patients are unable to exercise to target heart rate on a conventional treadmill. We examined the feasibility and safety of stress imaging using an anti-gravity treadmill in patients with perceived poor exercise capacity. 49 patients were recruited for stress testing by anti-gravity treadmill (n = 29) or to a regadenoson control group (n = 20). Seventeen anti-gravity test patients (59%) reached target heart rate obviating the need for a pharmacologic stress agent. Adverse effects of the anti-gravity treadmill were limited to minor muscle aches in 5 subjects. Stress myocardial perfusion image quality judged by 3 blinded readers on a 5-point scale was comparable for the anti-gravity treadmill (4.30 ± SD 0.87) vs pharmacologic stress (4.28 ± SD 0.66). Stress testing using an anti-gravity treadmill is feasible and may help some patients safely achieve target heart rate.

A perspective on the future role of brain pet imaging in exercise science.

PubMed

Boecker, Henning; Drzezga, Alexander

2016-05-01

Positron Emission Tomography (PET) bears a unique potential for examining the effects of physical exercise (acute or chronic) within the central nervous system in vivo, including cerebral metabolism, neuroreceptor occupancy, and neurotransmission. However, application of Neuro-PET in human exercise science is as yet surprisingly sparse. To date the field has been dominated by non-invasive neuroelectrical techniques (EEG, MEG) and structural/functional magnetic resonance imaging (sMRI/fMRI). Despite PET having certain inherent disadvantages, in particular radiation exposure and high costs limiting applicability at large scale, certain research questions in human exercise science can exclusively be addressed with PET: The "metabolic trapping" properties of (18)F-FDG PET as the most commonly used PET-tracer allow examining the neuronal mechanisms underlying various forms of acute exercise in a rather unconstrained manner, i.e. under realistic training scenarios outside the scanner environment. Beyond acute effects, (18)F-FDG PET measurements under resting conditions have a strong prospective for unraveling the influence of regular physical activity on neuronal integrity and potentially neuroprotective mechanisms in vivo, which is of special interest for aging and dementia research. Quantification of cerebral glucose metabolism may allow determining the metabolic effects of exercise interventions in the entire human brain and relating the regional cerebral rate of glucose metabolism (rCMRglc) with behavioral, neuropsychological, and physiological measures. Apart from FDG-PET, particularly interesting applications comprise PET ligand studies that focus on dopaminergic and opioidergic neurotransmission, both key transmitter systems for exercise-related psychophysiological effects, including mood changes, reward processing, antinociception, and in its most extreme form 'exercise dependence'. PET ligand displacement approaches even allow quantifying specific endogenous neurotransmitter release under acute exercise interventions, to which modern PET/MR hybrid technology will be additionally fruitful. Experimental studies exploiting the unprecedented multimodal imaging capacities of PET/MR in human exercise sciences are as yet pending. Copyright © 2015 Elsevier Inc. All rights reserved.

Au 2PbP 2, Au 2TlP 2, and Au 2HgP 2: Ternary Gold Polyphosphides with Lead, Thallium, and Mercury in the Oxidation State Zero

NASA Astrophysics Data System (ADS)

Eschen, Marcus; Jeitschko, Wolfgang

2002-05-01

The polyphosphide Au2PbP2 was prepared by reaction of the elemental components using liquid lead as a reaction medium. Well-developed crystals were obtained after dissolving the matrix in hydrochloric acid. Their crystal structure was determined from four-circle X-ray diffractometer data: Cmcm, a=323.6(1) pm, b=1137.1(2) pm, c=1121.8(1) pm, Z=4, R=0.023 for 478 structure factors and 20 variable parameters. The structure contains zigzag chains of phosphorus atoms with a typical single-bond distance of 219.4(2) pm. The two different kinds of gold atoms are both in linear phosphorus coordination with typical single-bond distances of 232.6(2) and 234.2(2) pm, and the lead atoms have only metal neighbors (7 Au and 2 Pb). Accordingly, chemical bonding of the compound may be expressed by the formula (Au+1)2Pb±0(P-1)2. The corresponding thallium and mercury polyphosphides Au2TlP2 (a=324.1(1) pm, b=1136.1(1) pm, c=1122.1(1) pm) and Au2HgP2 (a=322.1(1) pm, b=1131.4(2) pm, c=1122.6(1) pm) were found to be almost isotypic with Au2PbP2. Their crystal structures were refined from single-crystal X-ray data to R=0.036 (682 F values, 25 variables) and R=0.026 (539 F values, 35 variables), respectively. The structure of these compounds may also be described as consisting of a three-dimensional network of condensed 8- and 10-membered Au2P6 and Au4P6 rings forming parallel channels, which are filled by the lead, thallium, and mercury atoms. The lead atoms are well localized in these channels, while the thallium and even more the mercury atoms occupy additional positions within these channels. Freshly prepared samples of Au2HgP2 show reproducibly slightly different axial ratios and larger cell volumes (ΔV=0.5%) than those after exposure of the samples to air for several days.

Spatial Variation in Mobility-Lifetime Product in Bulk TlBr and CZT

NASA Astrophysics Data System (ADS)

Phillips, David; Haegel, Nancy; Blaine, Kevin; Kim, Hadong; Ciampi, Guido; Cirignano, Len

2012-02-01

The energy resolution of a semiconductor radiation detector depends on the charge transport properties of the semiconductor, and the mobility-lifetime (μτ) product is a key figure of merit for charge transport. In this work, we investigate the effects of two impurities, Na and Cu, on the μτ product in bulk thallium bromide (TlBr) using cathodoluminescence (CL) and transport imaging. Transport imaging uses a scanning electron microscope to generate a line of charge carriers on the surface of a bulk sample, and the intensity and spatial distribution of the recombination luminescence are recorded. A Green's function approach is used to model the generation, diffusion, and recombination of charge carriers under steady-state conditions. The luminescence distribution is fit to the model to extract the ambipolar diffusion length and the μτ product, providing a high-resolution correlation between the luminescence variations due to dopants/defects and the quantitative transport behavior. The μτ product has been mapped across a 40 μm segment of TlBr at a resolution of 2 μm. Additionally, this approach has been used to locally map variations in ambipolar diffusion length and μτ product due to extended defects in cadmium zinc telluride (CZT).

A low cost method for hard x-ray grating interferometry.

PubMed

Du, Yang; Lei, Yaohu; Liu, Xin; Huang, Jianheng; Zhao, Zhigang; Guo, Jinchuan; Li, Ji; Niu, Hanben

2016-12-07

Grating interferometry is advantageous over conventional x-ray absorption imaging because it enables the detection of samples constituted by low atomic number elements (low-Z materials). Therefore, it has a potential application in biological science and medical diagnostics. The grating interferometry has some critical optics components such as absorption gratings which are conventionally manufactured by the lithography, electroplating, and molding (LIGA) technique and employing gold as the absorbent material in it. However, great challenge lies in its implementations for practical applications because of the cost and difficulty to achieve high aspect ratio absorbing grating devices. In this paper, we present a low-cost approach that involves using the micro-casting technique with bismuth (Bi) as the absorber in source grating and as well as filling cesium iodide thallium(CsI:Tl) in a periodically structured scintillator. No costly facilities as synchrotron radiation are required and cheap material is used in our approach. Our experiment using these components shows high quality complementary images can be obtained with contrast of absorption, phase and visibility. This alternative method conquers the limitation of costly grating devices for a long time and stands an important step towards the further practical application of grating interferometry.

"Exercise to be fit, not skinny": The effect of fitspiration imagery on women's body image.

PubMed

Tiggemann, Marika; Zaccardo, Mia

2015-09-01

Fitspiration is an online trend designed to inspire viewers towards a healthier lifestyle by promoting exercise and healthy food. The present study aimed to experimentally investigate the impact of fitspiration images on women's body image. Participants were 130 female undergraduate students who were randomly assigned to view either a set of Instagram fitspiration images or a control set of travel images presented on an iPad. Results showed that acute exposure to fitspiration images led to increased negative mood and body dissatisfaction and decreased state appearance self-esteem relative to travel images. Importantly, regression analyses showed that the effects of image type were mediated by state appearance comparison. Thus it was concluded that fitspiration can have negative unintended consequences for body image. The results offer support to general sociocultural models of media effects on body image, and extend these to "new" media. Copyright © 2015 Elsevier Ltd. All rights reserved.

SU-C-201-04: Quantification of Perfusion Heterogeneity Based On Texture Analysis for Fully Automatic Detection of Ischemic Deficits From Myocardial Perfusion Imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fang, Y; Huang, H; Su, T

Purpose: Texture-based quantification of image heterogeneity has been a popular topic for imaging studies in recent years. As previous studies mainly focus on oncological applications, we report our recent efforts of applying such techniques on cardiac perfusion imaging. A fully automated procedure has been developed to perform texture analysis for measuring the image heterogeneity. Clinical data were used to evaluate the preliminary performance of such methods. Methods: Myocardial perfusion images of Thallium-201 scans were collected from 293 patients with suspected coronary artery disease. Each subject underwent a Tl-201 scan and a percutaneous coronary intervention (PCI) within three months. The PCImore » Result was used as the gold standard of coronary ischemia of more than 70% stenosis. Each Tl-201 scan was spatially normalized to an image template for fully automatic segmentation of the LV. The segmented voxel intensities were then carried into the texture analysis with our open-source software Chang Gung Image Texture Analysis toolbox (CGITA). To evaluate the clinical performance of the image heterogeneity for detecting the coronary stenosis, receiver operating characteristic (ROC) analysis was used to compute the overall accuracy, sensitivity and specificity as well as the area under curve (AUC). Those indices were compared to those obtained from the commercially available semi-automatic software QPS. Results: With the fully automatic procedure to quantify heterogeneity from Tl-201 scans, we were able to achieve a good discrimination with good accuracy (74%), sensitivity (73%), specificity (77%) and AUC of 0.82. Such performance is similar to those obtained from the semi-automatic QPS software that gives a sensitivity of 71% and specificity of 77%. Conclusion: Based on fully automatic procedures of data processing, our preliminary data indicate that the image heterogeneity of myocardial perfusion imaging can provide useful information for automatic determination of the myocardial ischemia.« less

A controlled intervention to promote a healthy body image, reduce eating disorder risk and prevent excessive exercise among trainee health education and physical education teachers.

PubMed

Yager, Zali; O'Dea, Jennifer

2010-10-01

This study examined the impact of two interventions on body image, eating disorder risk and excessive exercise among 170 (65% female) trainee health education and physical education (HE&PE) teachers of mean (standard deviation) age 21.6 (2.3) who were considered an 'at-risk' population for poor body image and eating disorders. In the first year of the study, the control group cohort (n = 49 females, 20 males) received the regular didactic health education curriculum; in the second year of the study, the Intervention 1 cohort (n = 31 females, 21 males) received a self-esteem and media literacy health education program and in the third year of the study, the Intervention 2 cohort (n = 30 females, 19 males) received a combined self-esteem, media literacy and dissonance program using online and computer-based activities. Intervention 2 produced the best results, with males improving significantly in self-esteem, body image and drive for muscularity. Intervention 2 females improved significantly on Eating Disorders Inventory Drive for Thinness, Eating Disorder Examination and excessive exercise. The improvements were consistent at 6-month follow-up for females. It is feasible to promote body image, reduce body dissatisfaction and reduce excessive exercise among trainee HE&PE teachers via a health education curriculum.

Effects of Image-Based and Text-Based Active Learning Exercises on Student Examination Performance in a Musculoskeletal Anatomy Course

ERIC Educational Resources Information Center

Gross, M. Melissa; Wright, Mary C.; Anderson, Olivia S.

2017-01-01

Research on the benefits of visual learning has relied primarily on lecture-based pedagogy, but the potential benefits of combining active learning strategies with visual and verbal materials on learning anatomy has not yet been explored. In this study, the differential effects of text-based and image-based active learning exercises on examination…

Differences in neural activation to depictions of physical exercise and sedentary activity: an fMRI study of overweight and lean Chinese women.

PubMed

Jackson, T; Gao, X; Chen, H

2014-09-01

Neuroimaging studies have documented differences in neural responses to food cues in obese versus lean samples but little is known about weight status differences in responsiveness to other key features of obesogenic environments, particularly cues reflecting physical activity. To address this gap, patterns of activation related to visual depictions of sedentary activities and vigorous physical exercise were assessed in overweight (O-W) and average weight (A-W) samples via functional magnetic resonance imaging (fMRI). Thirteen O-W and 13 A-W Chinese women were instructed to imagine engaging in 90 physical exercise activities and 90 sedentary activities and to watch 90 landscape images presented during three runs of an fMRI scan within a cross-sectional design. Behavioral results indicated O-W women endorsed more negative attitudes toward physical activity than A-W did. Imaging analyses indicated that body mass index had a significant negative association with activation of the right putamen and a positive correlation with activation in the right medial frontal gyrus, specifically Brodmann Area 10 in the exercise-sedentary image contrast condition. For the sedentary-control contrast, significantly less activation in an insula area related to negative affect was observed for the O-W group. Finally, for the exercise-control contrast, O-W women also displayed comparatively weaker activation in a cingulate gyrus area implicated in kinesthetic memory of body movements and the re-experiencing real events. Together, results supported contentions that exposure to depictions of physical exercise corresponds to reduced activation of reward centers and heightened activation in regions associated with negative affect regulation among O-W women compared with leaner peers.

Effect of resistance training on muscle use during exercise

NASA Technical Reports Server (NTRS)

Ploutz, Lori L.; Tesch, Per A.; Biro, Ronald L.; Dudley, Gary A.

1994-01-01

This study examined the effect of resistance training on exercise-induced contrast shift in magnetic resonance (MR) images. It was hypothesized that a given load could be lifted after training with less muscle showing contrast shift, thereby suggesting less muscle was used to perform the exercise. Nine males trained the left quadriceps femoris (QF) muscle 2 days/wk for 9 wk using 3-6 sets of 12 knee extensions each day. The right QF served as a control. Exercise-induced contrast shifts in MR images evoked by each of three bouts of exercise (5 sets of 10 knee extensions with a load equal to 50, 75, and 100% of the maximum pretraining load that could be lifted for 5 sets of 10 repetitions) were quantified pre- and posttraining. MR image contrast shift was quantified by determining QF cross-sectional area (CSA) showing increased spin-spin relaxation time. One repetition maximum increased 14% in the left trained QF and 7% in the right untrained QF. Left QF CSA increased 5%, with no change in right QSF CSA. Left QF CSA showing contrast shift was less after each bout of the exercise test posttraining. This was also true, to a lesser extent, for the right QF at the higher two loads. The results suggest that short-term resistance training reduces MR image contrast shift evoked by a given effort, thereby reflecting the use of less muscle to lift the load. Because this response was evident in both trained and contralateral untrained muscle, neural factors are suggested to be responsible. The consequence of this adaptation could be to increase 'stress' per unit area of active muscle during the course of training and thereby evoke hypertrophy.

40 CFR 141.51 - Maximum contaminant level goals for inorganic contaminants.

Code of Federal Regulations, 2010 CFR

2010-07-01

...: Contaminant MCLG (mg/l) Antimony 0.006 Arsenic zero 1 Asbestos 7 Million fibers/liter (longer than 10 µm... Nitrogen). Selenium 0.05 Thallium .0005 1 This value for arsenic is effective January 23, 2006. Until then...

Hard-X-Ray/Soft-Gamma-Ray Imaging Sensor Assembly for Astronomy

NASA Technical Reports Server (NTRS)

Myers, Richard A.

2008-01-01

An improved sensor assembly has been developed for astronomical imaging at photon energies ranging from 1 to 100 keV. The assembly includes a thallium-doped cesium iodide scintillator divided into pixels and coupled to an array of high-gain avalanche photodiodes (APDs). Optionally, the array of APDs can be operated without the scintillator to detect photons at energies below 15 keV. The array of APDs is connected to compact electronic readout circuitry that includes, among other things, 64 independent channels for detection of photons in various energy ranges, up to a maximum energy of 100 keV, at a count rate up to 3 kHz. The readout signals are digitized and processed by imaging software that performs "on-the-fly" analysis. The sensor assembly has been integrated into an imaging spectrometer, along with a pair of coded apertures (Fresnel zone plates) that are used in conjunction with the pixel layout to implement a shadow-masking technique to obtain relatively high spatial resolution without having to use extremely small pixels. Angular resolutions of about 20 arc-seconds have been measured. Thus, for example, the imaging spectrometer can be used to (1) determine both the energy spectrum of a distant x-ray source and the angular deviation of the source from the nominal line of sight of an x-ray telescope in which the spectrometer is mounted or (2) study the spatial and temporal development of solar flares, repeating - ray bursters, and other phenomena that emit transient radiation in the hard-x-ray/soft- -ray region of the electromagnetic spectrum.

[Myocardial imaging in acute myocardial infarction using beta-methyl-p-(123I)-iodophenylpentadecanoic acid: comparison with 201Tl imaging and wall motion].

PubMed

Naruse, H; Itano, M; Kondo, T; Kogame, T; Yamamoto, J; Morita, M; Kawamoto, H; Fukutake, N; Ohyanagi, M; Iwasaki, T

1992-01-01

Myocardial imaging using beta-methyl-p-(123I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial imagings with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (TL) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than TL in the subacute phase, although the uptake of BMIPP correlated with that of TL (tau = 0.82, p less than 0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase (tau = 0.50, p less than 0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and TL alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of TL and WM.

Neural Basis of Working Memory Enhancement after Acute Aerobic Exercise: fMRI Study of Preadolescent Children.

PubMed

Chen, Ai-Guo; Zhu, Li-Na; Yan, Jun; Yin, Heng-Chan

2016-01-01

Working memory lies at the core of cognitive function and plays a crucial role in children's learning, reasoning, problem solving, and intellectual activity. Behavioral findings have suggested that acute aerobic exercise improves children's working memory; however, there is still very little knowledge about whether a single session of aerobic exercise can alter working memory's brain activation patterns, as assessed by functional magnetic resonance imaging (fMRI). Therefore, we investigated the effect of acute moderate-intensity aerobic exercise on working memory and its brain activation patterns in preadolescent children, and further explored the neural basis of acute aerobic exercise on working memory in these children. We used a within-subjects design with a counterbalanced order. Nine healthy, right-handed children were scanned with a Siemens MAGNETOM Trio 3.0 Tesla magnetic resonance imaging scanner while they performed a working memory task (N-back task), following a baseline session and a 30-min, moderate-intensity exercise session. Compared with the baseline session, acute moderate-intensity aerobic exercise benefitted performance in the N-back task, increasing brain activities of bilateral parietal cortices, left hippocampus, and the bilateral cerebellum. These data extend the current knowledge by indicating that acute aerobic exercise enhances children's working memory, and the neural basis may be related to changes in the working memory's brain activation patterns elicited by acute aerobic exercise.

Semiquantitative Analysis Using Thallium-201 SPECT for Differential Diagnosis Between Tumor Recurrence and Radiation Necrosis After Gamma Knife Surgery for Malignant Brain Tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsunaga, Shigeo, E-mail: shigeo-m@mui.biglobe.ne.jp; Shuto, Takashi; Takase, Hajime

Purpose: Semiquantitative analysis of thallium-201 chloride single photon emission computed tomography ({sup 201}Tl SPECT) was evaluated for the discrimination between recurrent brain tumor and delayed radiation necrosis after gamma knife surgery (GKS) for metastatic brain tumors and high-grade gliomas. Methods and Materials: The medical records were reviewed of 75 patients, including 48 patients with metastatic brain tumor and 27 patients with high-grade glioma who underwent GKS in our institution, and had suspected tumor recurrence or radiation necrosis on follow-up neuroimaging and deteriorating clinical status after GKS. Analysis of {sup 201}Tl SPECT data used the early ratio (ER) and the delayedmore » ratio (DR) calculated as tumor/normal average counts on the early and delayed images, and the retention index (RI) as the ratio of DR to ER. Results: A total of 107 tumors were analyzed with {sup 201}Tl SPECT. Nineteen lesions were removed surgically and histological diagnoses established, and the other lesions were evaluated with follow-up clinical and neuroimaging examinations after GKS. The final diagnosis was considered to be recurrent tumor in 65 lesions and radiation necrosis in 42 lesions. Semiquantitative analysis demonstrated significant differences in DR (P=.002) and RI (P<.0001), but not in ER (P=.372), between the tumor recurrence and radiation necrosis groups, and no significant differences between metastatic brain tumors and high-grade gliomas in all indices (P=.926 for ER, P=.263 for DR, and P=.826 for RI). Receiver operating characteristics analysis indicated that RI was the most informative index with the optimum threshold of 0.775, which provided 82.8% sensitivity, 83.7% specificity, and 82.8% accuracy. Conclusions: Semiquantitative analysis of {sup 201}Tl SPECT provides useful information for the differentiation between tumor recurrence and radiation necrosis in metastatic brain tumors and high-grade gliomas after GKS, and the RI may be the most valuable index for this purpose.« less

Cardiovascular mortality prediction in veterans with arm exercise vs pharmacologic myocardial perfusion imaging.

PubMed

Martin, Wade H; Xian, Hong; Chandiramani, Pooja; Bainter, Emily; Klein, Andrew J P

2015-08-01

No data exist comparing outcome prediction from arm exercise vs pharmacologic myocardial perfusion imaging (MPI) stress test variables in patients unable to perform treadmill exercise. In this retrospective study, 2,173 consecutive lower extremity disabled veterans aged 65.4 ± 11.0years (mean ± SD) underwent either pharmacologic MPI (1730 patients) or arm exercise stress tests (443 patients) with MPI (n = 253) or electrocardiography alone (n = 190) between 1997 and 2002. Cox multivariate regression models and reclassification analysis by integrated discrimination improvement (IDI) were used to characterize stress test and MPI predictors of cardiovascular mortality at ≥10-year follow-up after inclusion of significant demographic, clinical, and other variables. Cardiovascular death occurred in 561 pharmacologic MPI and 102 arm exercise participants. Multivariate-adjusted cardiovascular mortality was predicted by arm exercise resting metabolic equivalents (hazard ratio [HR] 0.52, 95% CI 0.39-0.69, P < .001), 1-minute heart rate recovery (HR 0.61, 95% CI 0.44-0.86, P < .001), and pharmacologic and arm exercise delta (peak-rest) heart rate (both P < .001). Only an abnormal arm exercise MPI prognosticated cardiovascular death by multivariate Cox analysis (HR 1.98, 95% CI 1.04-3.77, P < .05). Arm exercise MPI defect number, type, and size provided IDI over covariates for prediction of cardiovascular mortality (IDI = 0.074-0.097). Only pharmacologic defect size prognosticated cardiovascular mortality (IDI = 0.022). Arm exercise capacity, heart rate recovery, and pharmacologic and arm exercise heart rate responses are robust predictors of cardiovascular mortality. Arm exercise MPI results are equivalent and possibly superior to pharmacologic MPI for cardiovascular mortality prediction in patients unable to perform treadmill exercise. Published by Elsevier Inc.

Exertional muscle injury: evaluation of concentric versus eccentric actions with serial MR imaging.

PubMed

Shellock, F G; Fukunaga, T; Mink, J H; Edgerton, V R

1991-06-01

Eccentric muscular actions involve the forced lengthening or stretching of muscles and tend to produce exertional injuries. This study used magnetic resonance (MR) imaging to serially evaluate muscles in five healthy, untrained subjects who performed exhaustive biceps exercise by doing isolated eccentric and concentric actions with a dumbbell. Symptoms were assessed, and T2-weighted images of the arms were obtained before exercise and 1, 3, 5, 10, 25, 40, 50, 60, and 80 days after exercise. Statistically significant increases in T2 relaxation times indicative of muscle injury occurred on each day of MR imaging evaluation in muscles performing eccentric actions, peaking on day 3 in two subjects; day 5, two subjects; and day 10, one subject. The pattern and extent of the abnormalities on MR images were variable. Pain, soreness, and joint stiffness were present on days 1, 3, and 5 in muscles that performed eccentric actions. MR imaging showed subclinical abnormalities that lasted as long as 75 days after the disappearance of symptoms (two subjects). Muscles that performed concentric actions had no changes in T2 relaxation times and were asymptomatic throughout the study.

Countermeasures against lumbar spine deconditioning in prolonged bed rest: resistive exercise with and without whole body vibration.

PubMed

Belavý, Daniel L; Armbrecht, Gabriele; Gast, Ulf; Richardson, Carolyn A; Hides, Julie A; Felsenberg, Dieter

2010-12-01

To evaluate the effect of short-duration, high-load resistive exercise, with and without whole body vibration on lumbar muscle size, intervertebral disk and spinal morphology changes, and low back pain (LBP) incidence during prolonged bed rest, 24 subjects underwent 60 days of head-down tilt bed rest and performed either resistive vibration exercise (n = 7), resistive exercise only (n = 8), or no exercise (n = 9; 2nd Berlin Bed-Rest Study). Discal and spinal shape was measured from sagittal plane magnetic resonance images. Cross-sectional areas (CSAs) of the multifidus, erector spinae, quadratus lumborum, and psoas were measured on para-axial magnetic resonance images. LBP incidence was assessed with questionnaires at regular intervals. The countermeasures reduced CSA loss in the multifidus, lumbar erector spinae and quadratus lumborum muscles, with greater increases in psoas muscle CSA seen in the countermeasure groups (P ≤ 0.004). There was little statistical evidence for an additional effect of whole body vibration above resistive exercise alone on these muscle changes. Exercise subjects reported LBP more frequently in the first week of bed rest, but this was only significant in resistive exercise only (P = 0.011 vs. control, resistive vibration exercise vs. control: P = 0.56). No effect of the countermeasures on changes in spinal morphology was seen (P ≥ 0.22). The results suggest that high-load resistive exercise, with or without whole body vibration, performed 3 days/wk can reduce lumbar muscle atrophy, but further countermeasure optimization is required.

What Is Stress Testing?

MedlinePlus

... Research Home / < Back To Health Topics / Stress Testing Stress Testing Also known as What Is Stress Testing? ... test and an imaging stress test. Standard Exercise Stress Test A standard exercise stress test uses an ...

Compulsive Exercise

MedlinePlus

... diseases. Many teens who play sports have higher self-esteem than their less active pals, and exercise can ... may have a distorted body image and low self-esteem. They may see themselves as overweight or out ...

Tackling misconceptions in geometrical optics

NASA Astrophysics Data System (ADS)

Ceuppens, S.; Deprez, J.; Dehaene, W.; De Cock, M.

2018-07-01

To improve the teaching and learning materials for a curriculum it is important to incorporate the findings from educational research. In light of this, we present creative exercises and experiments to elicit, confront and resolve misconceptions in geometrical optics. Since ray diagrams can be both the cause and the solution for many misconceptions we focus strongly on improving understanding of this tool to solve and understand optical phenomena. Through a combination of a conceptual understanding programme (CUP) and provocative exercises with ray diagrams we aim to elicit conceptual or cognitive conflict and exploit this to tackle misconceptions and increase students’ conceptual understanding through inquiry. We describe exercises for image formation by a plane mirror, image formation by a convex lens and indirect and direct observation of a real image formed by a convex lens as examples of our approach.

Creation and characterization of normal myocardial perfusion imaging databases using the IQ·SPECT system.

PubMed

Okuda, Koichi; Nakajima, Kenichi; Matsuo, Shinro; Kondo, Chisato; Sarai, Masayoshi; Horiguchi, Yoriko; Konishi, Takahiro; Onoguchi, Masahisa; Shimizu, Takeshi; Kinuya, Seigo

2017-01-03

Image acquisition by short-time single-photon emission-computed tomography (SPECT) has been made feasible by IQ·SPECT. The aim of this study was to generate normal databases (NDBs) of thallium-201 ( 201 Tl) myocardial perfusion imaging for IQ·SPECT, and characterize myocardial perfusion distribution. We retrospectively enrolled 159 patients with a low likelihood of cardiac diseases from four hospitals in Japan. All patients underwent short-time 201 Tl myocardial perfusion IQ·SPECT with or without attenuation and scatter correction (ACSC) in either supine or prone position. The mean myocardial counts were calculated using 17-segment polar maps. Three NDBs were derived from supine and prone images as well as supine images with ACSC. Differences between the supine and prone positions were observed in the uncorrected sex-segregated NDBs in the mid-inferolateral counts (p ≤ 0.016 for males and p ≤ 0.002 for females). Differences between IQ·SPECT and conventional SPECT were also observed in the mid-anterior, inferolateral, and apical lateral counts (p ≤ 0.009 for males and p ≤ 0.003 for females). Apical low counts attributed to myocardial thinning were observed in the apical anterior and apex segments in the supine IQ·SPECT NDB with ACSC. There were significant differences between uncorrected supine and prone NDBs, between uncorrected supine NDB and supine NDB with ACSC, and between uncorrected supine NDB and conventional SPECT NDB. Understanding the pattern of normal distribution in IQ-SPECT short-time acquisitions with and without ACSC will be helpful for interpretation of imaging findings in patients with coronary artery disease (CAD) or low likelihood of CAD and the NDBs will aid in quantitative analysis.

EPA Method 200.8: Determination of Trace Elements in Waters and Wastes by Inductively Coupled Plasma-Mass Spectrometry

EPA Pesticide Factsheets

\\tEPA’s Selected Analytical Methods for Environmental Remediation and Recovery (SAM) lists this method for preparation and analysis of drinking water samples to detect and measure compounds containing arsenic, thallium and vanadium.

Physical and Emotional Benefits of Different Exercise Environments Designed for Treadmill Running

PubMed Central

Churchill, Sarah M.; Brymer, Eric; Davids, Keith

2017-01-01

(1) Background: Green physical activity promotes physical health and mental wellbeing and interesting questions concern effects of this information on designing indoor exercise environments. This study examined the physical and emotional effects of different nature-based environments designed for indoor treadmill running; (2) Methods: In a counterbalanced experimental design, 30 participants performed three, twenty-minute treadmill runs at a self-selected pace while viewing either a static nature image, a dynamic nature image or self-selected entertainment. Distance ran, heart rate (HR) and five pre-and post-exercise emotional states were measured; (3) Results: Participants ran farther, and with higher HRs, with self-selected entertainment compared to the two nature-based environment designs. Participants attained lowered anger, dejection, anxiety and increased excitement post exercise in all of the designed environments. Happiness increased during the two nature-based environment designs compared with self-selected entertainment; (4) Conclusions: Self-selected entertainment encouraged greater physical performances whereas running in nature-based exercise environments elicited greater happiness immediately after running. PMID:28696384

Physical and Emotional Benefits of Different Exercise Environments Designed for Treadmill Running.

PubMed

Yeh, Hsiao-Pu; Stone, Joseph A; Churchill, Sarah M; Brymer, Eric; Davids, Keith

2017-07-11

(1) Background: Green physical activity promotes physical health and mental wellbeing and interesting questions concern effects of this information on designing indoor exercise environments. This study examined the physical and emotional effects of different nature-based environments designed for indoor treadmill running; (2) Methods: In a counterbalanced experimental design, 30 participants performed three, twenty-minute treadmill runs at a self-selected pace while viewing either a static nature image, a dynamic nature image or self-selected entertainment. Distance ran, heart rate (HR) and five pre-and post-exercise emotional states were measured; (3) Results: Participants ran farther, and with higher HRs, with self-selected entertainment compared to the two nature-based environment designs. Participants attained lowered anger, dejection, anxiety and increased excitement post exercise in all of the designed environments. Happiness increased during the two nature-based environment designs compared with self-selected entertainment; (4) Conclusions: Self-selected entertainment encouraged greater physical performances whereas running in nature-based exercise environments elicited greater happiness immediately after running.

Use of thermal imagery for estimation of core body temperature during precooling, exertion, and recovery in wildland firefighter protective clothing.

PubMed

Bourlai, Thirimachos; Pryor, Riana R; Suyama, Joe; Reis, Steven E; Hostler, David

2012-01-01

Monitoring core body temperature to identify heat stress in first responders and in individuals participating in mass gatherings (e.g., marathons) is difficult. This study utilized high-sensitivity thermal imaging technology to predict the core temperature of human subjects at a distance while performing simulated field operations wearing thermal protective garments. Six male subjects participating in a study of precooling prior to exertion in wildland firefighter thermal protective clothing had thermal images of the face captured with a high-resolution thermal imaging camera concomitant with measures of core and skin temperature before, during, and after treadmill exercise in a heated room. Correlations and measures of agreement between core temperature and thermal imaging-based temperature were performed. The subjects walked an average (± standard deviation) of 42.6 (±5.9) minutes and a distance of 4.2 (±0.6) km on the treadmill. Mean heart rate at the end of exercise was 152 (±33) bpm and core body temperature at the end of exercise was 38.3°C (±0.7°C). A visual relationship and a strong correlation between core temperature and thermal imaging of the face were identified in all subjects, with the closest relationship and best agreement occurring during exercise. The Bland-Altman test of agreement during exercise revealed the majority of measurement pairs to be within two standard deviations of the measured temperature. High-resolution thermal imaging in the middle-wave infrared spectrum (3-5 μm) can be used to accurately estimate core body temperature during exertion in a hot room while participants are wearing wildland firefighting garments. Although this technology is promising, it must be refined. Using alternative measurement sites such as the skin over the carotid artery, using multiple measurement sites, or adding pulse detection may improve the estimation of body temperature by thermal imagery.

Magnetic resonance imaging and electromyography as indexes of muscle function

NASA Technical Reports Server (NTRS)

Adams, Gregory R.; Duvoisin, Marc R.; Dudley, Gary A.

1992-01-01

A hypothesis is tested that exercise-induced magnetic resonance (MR) contrast shifts would relate to electromyography (EMG) amplitude if both measures reflect muscle use during exercise. Both magnetic resonance images (MRI) and EMG data were obtained for separate eccentric (ECC) and cocentric (CON) exercise of increasing intensity for seven subjects 30-32 yr old. CON and ECC actions caused increased integrated EMG (IEMG) and T2 values which were strongly related with relative resistance. The rate of increase and absolute value of both T2 and IEMG were found to be greater for CON than for ECC actions. For both actions IEMG and T2 were correlated. Data obtained suggest that surface IEMG accurately reflects the contractile behavior of muscle and exercise-induced increases in MRI T2 values reflect certain processes that scale with muscle use.

Head-to-head comparison of peak supine bicycle exercise echocardiography and treadmill exercise echocardiography at peak and at post-exercise for the detection of coronary artery disease.

PubMed

Peteiro, Jesús; Bouzas-Mosquera, Alberto; Estevez, Rodrigo; Pazos, Pablo; Piñeiro, Miriam; Castro-Beiras, Alfonso

2012-03-01

Supine bicycle exercise (SBE) echocardiography and treadmill exercise (TME) echocardiography have been used for evaluation of coronary artery disease (CAD). Although peak imaging acquisition has been considered unfeasible with TME, higher sensitivity for the detection of CAD has been recently found with this method compared with post-TME echocardiography. However, peak TME echocardiography has not been previously compared with the more standardized peak SBE echocardiography. The aim of this study was to compare peak TME echocardiography, peak SBE echocardiography, and post-TME echocardiography for the detection of CAD. A series of 116 patients (mean age, 61 ± 10 years) referred for evaluation of CAD underwent SBE (starting at 25 W, with 25-W increments every 2-3 min) and TME with peak and postexercise imaging acquisition, in a random sequence. Digitized images at baseline, at peak TME, after TME, and at peak SBE were interpreted in a random and blinded fashion. All patients underwent coronary angiography. Maximal heart rate was higher during TME, whereas systolic blood pressure was higher during SBE, resulting in similar rate-pressure products. On quantitative angiography, 75 patients had coronary stenosis (≥50%). In these patients, wall motion score indexes at maximal exercise were higher at peak TME (median, 1.45; interquartile range [IQR], 1.13-1.75) than at peak SBE (median, 1.25; IQR, 1.0-1.56) or after TME (median, 1.13; IQR, 1.0-1.38) (P = .002 between peak TME and peak SBE imaging, P < .001 between post-TME imaging and the other modalities). The extent of myocardial ischemia (number of ischemic segments) was also higher during peak TME (median, 5; IQR, 2-12) compared with peak SBE (median, 3; IQR, 0-8) or after TME (median, 2; IQR, 0-4) (P < .001 between peak TME and peak SBE imaging, P < .001 between post-TME imaging and the other modalities). ST-segment changes in patients with CAD and normal baseline ST segments were higher during TME (median, 1 mm [IQR, 0-1.9 mm] vs 0 mm [IQR, 0-1.5 mm]; P = .006). The sensitivity of peak TME, peak SBE, and post-TME echocardiography for CAD was 84%, 75%, and 60% (P = .001 between post-TME and peak TME echocardiography, P = .055 between post-TME and peak SBE echocardiography), with specificity of 63%, 80%, and 78%, respectively (P = NS) and accuracy of 77%, 77%, and 66%, respectively (P = NS). Peak TME echocardiography diagnosed multivessel disease in 27 of the 40 patients with stenoses in more than one coronary artery, in contrast to 17 patients with peak SBE imaging and 12 with post-TME imaging (P < .05 between peak TME imaging and the other modalities). Image quality was similar with the three techniques. The duration of the test was longer with SBE echocardiography (9.5 ± 3.8 vs 7.6 ± 2.5 min, P < .001). During TME and SBE, patients achieve similar double products. Ischemia is more extensive and frequent with peak TME, which makes peak TME a more valuable exercise echocardiographic modality to increase sensitivity. However, peak SBE should be preferred to TME if the latter is performed with postexercise imaging acquisition. Copyright © 2012 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

How do you define body image? Exploring conceptual gaps in understandings of body image at an exercise facility.

PubMed

Bailey, K Alysse; Gammage, Kimberley L; van Ingen, Cathy

2017-12-01

The definition of body image has evolved within research; however, less is known about the layperson's understanding of the construct. This study explored how members and student trainees of an exercise facility (designed for older adults, people with physical disability, and those with cardiac complications) defined body image. Nineteen participants completed a one-on-one interview, and seven of those participants took part in six additional focus group meetings. The following main themes were found: stereotypical assumptions about body image (e.g., it is solely a person's weight or merely a woman's issue), body image continua for positive and negative body image, degree of complexity of body image dimensions, broad considerations of body image (e.g., it is self-esteem), and limited knowledge about body image. These findings suggest a need for knowledge translation between researchers and the general public which informs future body image program design. Copyright © 2017 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weaver, Virginia M., E-mail: vweaver@jhsph.edu; Johns Hopkins University School of Medicine, Baltimore, MD; Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD

Positive associations between urine toxicant levels and measures of glomerular filtration rate (GFR) have been reported recently in a range of populations. The explanation for these associations, in a direction opposite that of traditional nephrotoxicity, is uncertain. Variation in associations by urine concentration adjustment approach has also been observed. Associations of urine cadmium, thallium and uranium in models of serum creatinine- and cystatin-C-based estimated GFR (eGFR) were examined using multiple linear regression in a cross-sectional study of adolescents residing near a lead smelter complex. Urine concentration adjustment approaches compared included urine creatinine, urine osmolality and no adjustment. Median age, bloodmore » lead and urine cadmium, thallium and uranium were 13.9 years, 4.0 μg/dL, 0.22, 0.27 and 0.04 g/g creatinine, respectively, in 512 adolescents. Urine cadmium and thallium were positively associated with serum creatinine-based eGFR only when urine creatinine was used to adjust for urine concentration (β coefficient=3.1 mL/min/1.73 m{sup 2}; 95% confidence interval=1.4, 4.8 per each doubling of urine cadmium). Weaker positive associations, also only with urine creatinine adjustment, were observed between these metals and serum cystatin-C-based eGFR and between urine uranium and serum creatinine-based eGFR. Additional research using non-creatinine-based methods of adjustment for urine concentration is necessary. - Highlights: • Positive associations between urine metals and creatinine-based eGFR are unexpected. • Optimal approach to urine concentration adjustment for urine biomarkers uncertain. • We compared urine concentration adjustment methods. • Positive associations observed only with urine creatinine adjustment. • Additional research using non-creatinine-based methods of adjustment needed.« less

Redox-controlled release dynamics of thallium in periodically flooded arable soil.

PubMed

Antić-Mladenović, Svetlana; Frohne, Tina; Kresović, Mirjana; Stärk, Hans-Joachim; Savić, Dubravka; Ličina, Vlado; Rinklebe, Jörg

2017-07-01

To our knowledge, this is the first work to mechanistically study the impact of the redox potential (E H ) and principal factors, such as pH, iron (Fe), manganese (Mn), dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), chlorides (Cl - ) and sulfates (SO 4 2- ), on the release dynamics of thallium (Tl) in periodically flooded soil. We simulated flooding using an automated biogeochemical microcosm system that allows for systematical control of pre-defined redox windows. The E H value was increased mechanistically at intervals of approximately 100 mV from reducing (-211 mV) to oxidizing (475 mV) conditions. Soluble Tl levels (0.02-0.28 μg L -1 ) increased significantly with increases in E H (r = 0.80, p < 0.01, n = 30). Thallium mobilization was found to be related to several simultaneous processes involving the gradual oxidation of Tl-bearing sulfides, reductive dissolution of Fe-Mn oxides and desorption from mineral sorbents. Manganese oxides did not appear to have a considerable effect on Tl retention under oxidizing conditions. Before conducting the microcosm experiment, Tl geochemical fractionation was assessed using the modified BCR sequential extraction procedure. The BCR revealed a majority of Tl in the residual fraction (77.7%), followed by reducible (13.3%) and oxidizable fractions (5.9%). By generating high levels of Tl toxicity at low doses, Tl released under oxidizing conditions may pose an environmental threat. In the future, similar studies should be conducted on various soils along with a determination of the Tl species and monitoring of the Tl content in plants to achieve more detailed insight into soluble Tl behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

Alternative diagnostic strategies for coronary artery disease in women: demonstration of the usefulness and efficiency of probability analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melin, J.A.; Wijns, W.; Vanbutsele, R.J.

Alternative strategies using conditional probability analysis for the diagnosis of coronary artery disease (CAD) were examined in 93 infarct-free women presenting with chest pain. Another group of 42 consecutive female patients was prospectively analyzed. For this latter group, the physician had access to the pretest and posttest probability of CAD before coronary angiography. These 135 women all underwent stress electrocardiographic, thallium scintigraphic, and coronary angiographic examination. The pretest and posttest probabilities of coronary disease were derived from a computerized Bayesian algorithm. Probability estimates were calculated by the four following hypothetical strategies: SO, in which history, including risk factors, was considered;more » S1, in which history and stress electrocardiographic results were considered; S2, in which history and stress electrocardiographic and stress thallium scintigraphic results were considered; and S3, in which history and stress electrocardiographic results were used, but in which stress scintigraphic results were considered only if the poststress probability of CAD was between 10% and 90%, i.e., if a sufficient level of diagnostic certainty could not be obtained with the electrocardiographic results alone. The strategies were compared with respect to accuracy with the coronary angiogram as the standard. For both groups of women, S2 and S3 were found to be the most accurate in predicting the presence or absence of coronary disease (p less than .05). However, it was found with use of S3 that more than one-third of the thallium scintigrams could have been avoided without loss of accuracy. It was also found that diagnostic catheterization performed to exclude CAD as a diagnosis could have been avoided in half of the patients without loss of accuracy.(ABSTRACT TRUNCATED AT 250 WORDS)« less

Thallium dynamics in the southern North Sea

NASA Astrophysics Data System (ADS)

Böning, Philipp; Schnetger, Bernhard; Beck, Melanie; Brumsack, Hans-Jürgen

2018-04-01

In open ocean waters thallium (Tl) belongs to the group of conservative elements, even though deviations from this trend have been observed in NW German coastal waters. Here, we report on tidal, seasonal and spatial dynamics of Tl along with Mo and Mn in the water column of a backbarrier tidal flat close to the island of Spiekeroog, the Jade system (Inner Jade and Jade Bay) and the adjacent offshore region. Dissolved thallium (Tldiss) displays strong tidal and seasonal variations (∼25-60 pM) unrelated to salinity. In all study areas, Tldiss clearly deviates from conservative behavior. In general, Tldiss is low during low tide (with a loss of up to 50%) and inversely related to Mndiss, except in summer. The tidal Tl variations as well as the loss of Tl in the water column may be due to Tl removal from pore waters in reducing sediments and drainage of Tl-free but Mn-rich pore waters into the water column during low tide. The negative Tl anomaly can be traced offshore for more than 40 km to the island of Helgoland. The redox chemistry of Tl is not well studied, and Tl removal from pore waters was previously suggested to only occur under anoxic/sulfidic conditions. By contrast, our preliminary pore water results suggest that Tl could be removed already under slightly reducing (suboxic) conditions, likely along with microbially induced Mn reduction in the sediments. Therefore, this study supports the biological involvement in the aqueous cycling of Tl. We propose the use of Tldiss next to Mndiss as valuable indicator of suboxic or anoxic pore water discharge to the coastal realm.

Eating and Exercising: Nebraska Adolescents' Attitudes and Behaviors. Technical Report 25.

ERIC Educational Resources Information Center

Newman, Ian M.

This report describes selected eating and exercise patterns among a sample of 2,237 Nebraska youth in grades 9-12 selected from a random sample of 24 junior and senior high schools. The eating patterns reported cover food selection, body image, weight management, and weight loss methods. The exercise patterns relate to the frequency of…

Mind Maps as Classroom Exercises

ERIC Educational Resources Information Center

Budd, John W.

2004-01-01

A Mind Map is an outline in which the major categories radiate from a central image and lesser categories are portrayed as branches of larger branches. The author describes an in-class exercise in which small groups of students each create a Mind Map for a specific topic. This exercise is another example of an active and collaborative learning…

Influence of Goal Contents on Exercise Addiction: Analysing the Mediating Effect of Passion for Exercise

PubMed Central

Sicilia, Álvaro; Alcaraz-Ibáñez, Manuel; Lirola, María-Jesús; Burgueño, Rafael

2017-01-01

Abstract Based on the self-determination theory (Deci and Ryan, 1985, 2000), the purpose of this study was to examine the effects of exercise goal contents on exercise addiction, taking into account the mediating effects of passion for exercise. A total of 384 university students (284 men and 100 women; Mage = 20.31, SD = 3.10) completed a questionnaire that measured exercise frequency and intensity, exercise goal contents (e.g. intrinsic: social affiliation, health management, skill development; extrinsic: image and social recognition), passion for exercise (e.g. harmonious and obsessive), and exercise addiction. After controlling the exercise frequency and intensity effects, results showed that goal contents did not directly predict exercise addiction. However, mediation analysis showed that goal contents predicted addiction through passion for exercise. These results support a motivational sequence in which extrinsic versus intrinsic goals influence exercise addiction because such goals are positively associated with obsessive passion for exercise and negatively associated with harmonious passion. PMID:29134055

Influence of Goal Contents on Exercise Addiction: Analysing the Mediating Effect of Passion for Exercise.

PubMed

Sicilia, Álvaro; Alcaraz-Ibáñez, Manuel; Lirola, María-Jesús; Burgueño, Rafael

2017-10-01

Based on the self-determination theory (Deci and Ryan, 1985, 2000), the purpose of this study was to examine the effects of exercise goal contents on exercise addiction, taking into account the mediating effects of passion for exercise. A total of 384 university students (284 men and 100 women; M age = 20.31, SD = 3.10) completed a questionnaire that measured exercise frequency and intensity, exercise goal contents (e.g. intrinsic: social affiliation, health management, skill development; extrinsic: image and social recognition), passion for exercise (e.g. harmonious and obsessive), and exercise addiction. After controlling the exercise frequency and intensity effects, results showed that goal contents did not directly predict exercise addiction. However, mediation analysis showed that goal contents predicted addiction through passion for exercise. These results support a motivational sequence in which extrinsic versus intrinsic goals influence exercise addiction because such goals are positively associated with obsessive passion for exercise and negatively associated with harmonious passion.

[Effect of exercise load on apparent diffusion coefficient and fractional anisotropy of normal lumbar intervertebral discs in diffusion tensor imaging].

PubMed

Zhong, Xiu; Qiu, Shijun

2015-06-01

To investigate the effect of exercise load on apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of normal lumbar intervertebral discs in magnetic resonance (MR) diffusion tensor imaging (DTI). Thirty healthy volunteers (24 males and 6 females, aged 19 to 25 years) underwent examinations with MR T2WI and DTI of the lumbar intervertebral discs before and after exercise load. Pfirrmann grading was evaluated with T2WI, and the B0 map, ADC map and FA map were reconstructed based on the DTI data to investigate the changes in ADC and FA after exercise. Of the 30 volunteers (150 intervertebral discs) receiving the examination, 27 with discs of Pfirrminn grade II were included for analysis. In these 27 volunteers, the average ADC and FA before exercise were (1.99 ± 0.18)×10⁻³ mm²/s and 0.155∓0.059, respectively. After exercise, ADC was lowered significantly to (1.93 ± 0.17)×10⁻³ mm²/s (P<0.05) and FA increased slightly to 0.1623 ± 0.017 (P>0.05). DTI allows quantitatively analysis of the changes in water molecular diffusion and anisotropy of the lumbar intervertebral discs after exercise load, which can cause a decreased ADC and a increased FA value, and the change of ADC is more sensitive to exercise load.

Being active after a heart attack (image)

MedlinePlus

... best activity when you start exercising after a heart attack. Start slowly, and increase the amount of time ... best activity when you start exercising after a heart attack. Start slowly, and increase the amount of time ...

A randomized controlled trial comparing McKenzie therapy and motor control exercises on the recruitment of trunk muscles in people with chronic low back pain: a trial protocol.

PubMed

Halliday, Mark H; Ferreira, Paulo H; Hancock, Mark J; Clare, Helen A

2015-06-01

To investigate if McKenzie exercises when applied to a cohort of patients with chronic LBP who have a directional preference demonstrate improved recruitment of the transversus abdominis compared to motor control exercises when measurements were assessed from ultrasound images. A randomized blinded trial with a 12-month follow-up. The Physiotherapy department of Concord Hospital a primary health care environment. 70-adults with greater than three-month history of LBP who have a directional preference. McKenzie techniques or motor control exercises for 12-sessions over eight weeks. Transversus abdominus thickness measured from real time ultrasound images, pain, global perceived effect and capacity to self-manage. This study will be the first to investigate the possible mechanism of action that McKenzie therapy and motor control exercises have on the recruitment of the transversus abdominus in a cohort of low back pain patients sub-classified with a directional preference. Patients receiving matched exercises according to their directional preference are believed to have better outcomes than those receiving unmatched exercises. A better understanding of the mechanism of action that specific treatments such as motor control exercises or McKenzie exercises have on patients classified with a directional preference will allow therapist to make a more informed choice about treatment options. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Quadriceps muscle use in the flywheel and barbell squat.

PubMed

Norrbrand, Lena; Tous-Fajardo, Julio; Vargas, Roberto; Tesch, Per A

2011-01-01

Resistance exercise has been proposed as an aid to counteract quadriceps muscle atrophy in astronauts during extended missions in orbit. While space authorities have advocated the squat exercise should be prescribed, no exercise system suitable for in-flight use has been validated with regard to quadriceps muscle use. We compared muscle involvement in the terrestrial "gold standard" squat using free weights and a nongravity dependent flywheel resistance exercise device designed for use in space. The subjects were 10 strength-trained men who performed 5 sets of 10 repetitions using the barbell squat (BS; 10 repetition maximum) or flywheel squat (FS; each repetition maximal), respectively. Functional magnetic resonance imaging (MRI) and surface electromyography (EMG) techniques assessed quadriceps muscle use. Exercise-induced contrast shift of MR images was measured by means of transverse relaxation time (T2). EMG root mean square (RMS) was measured during concentric (CON) and eccentric (ECC) actions and normalized to EMG RMS determined during maximal voluntary contraction. The quadriceps muscle group showed greater exercise-induced T2 increase following FS compared with BS. Among individual muscles, the rectus femoris displayed greater T2 increase with FS (+24 +/- 14%) than BS (+8 +/- 4%). Normalized quadriceps EMG showed no difference across exercise modes. Collectively, the results of this study suggest that quadriceps muscle use in the squat is comparable, if not greater, with flywheel compared with free weight resistance exercise. Data appear to provide support for use of flywheel squat resistance exercise as a countermeasures adjunct during spaceflight.

Progress in Studying Scintillator Proportionality: Phenomenological Model

NASA Astrophysics Data System (ADS)

Bizarri, G.; Cherepy, N. J.; Choong, W. S.; Hull, G.; Moses, W. W.; Payne, S. A.; Singh, J.; Valentine, J. D.; Vasilev, A. N.; Williams, R. T.

2009-08-01

We present a model to describe the origin of non-proportional dependence of scintillator light yield on the energy of an ionizing particle. The non-proportionality is discussed in terms of energy relaxation channels and their linear and non-linear dependences on the deposited energy. In this approach, the scintillation response is described as a function of the deposited energy deposition and the kinetic rates of each relaxation channel. This mathematical framework allows both a qualitative interpretation and a quantitative fitting representation of scintillation non-proportionality response as function of kinetic rates. This method was successfully applied to thallium doped sodium iodide measured with SLYNCI, a new facility using the Compton coincidence technique. Finally, attention is given to the physical meaning of the dominant relaxation channels, and to the potential causes responsible for the scintillation non-proportionality. We find that thallium doped sodium iodide behaves as if non-proportionality is due to competition between radiative recombinations and non-radiative Auger processes.

Fabrication of double-sided thallium bromide strip detectors

NASA Astrophysics Data System (ADS)

Hitomi, Keitaro; Nagano, Nobumichi; Onodera, Toshiyuki; Kim, Seong-Yun; Ito, Tatsuya; Ishii, Keizo

2016-07-01

Double-sided strip detectors were fabricated from thallium bromide (TlBr) crystals grown by the traveling-molten zone method using zone-purified materials. The detectors had three 3.4-mm-long strips with 1-mm widths and a surrounding electrode placed orthogonally on opposite surfaces of the crystals at approximately 6.5×6.5 mm2 in area and 5 mm in thickness. Excellent charge transport properties for both electrons and holes were observed from the TlBr crystals. The mobility-lifetime products for electrons and holes in the detector were measured to be ~3×10-3 cm2/V and ~1×10-3 cm2/V, respectively. The 137Cs spectra corresponding to the gamma-ray interaction position were obtained from the detector. An energy resolution of 3.4% of full width at half maximum for 662-keV gamma rays was obtained from one "pixel" (an intersection of the strips) of the detector at room temperature.

An effective method for thallium bromide purification and research on crystal properties

NASA Astrophysics Data System (ADS)

Zheng, Zhiping; Meng, Fang; Gong, Shuping; Quan, Lin; Wang, Jing; Zhou, Dongxiang

2012-06-01

Thallium bromide (TlBr) is a promising candidate for room-temperature X- and gamma-ray detectors in view of its excellent intrinsic features. However, material purity and crystal quality concerns still limit the use of TlBr crystals as detectors. In this work, a combination of hydrothermal recrystallization (HR) and vacuum distillation (VD) methods were applied to purify TlBr salts prior to crystal growth. Trace impurities at the ppb/ppm level were determined by inductively coupled plasma mass spectroscopy (ICP-MS). The results showed that the impurity concentrations of the TlBr salt decreased significantly after HR and VD purification, and high performance of the resultant TlBr crystal in areas such as electrical and optical properties was achieved. The combination of HR and VD methods could fabricate purer material, with an order of magnitude higher resistivity and better optical quality, than HR or VD method used separately. The possible technological considerations affecting the parameters of the crystals are investigated.

Continued development of thallium bromide and related compounds for gamma-ray spectrometers

NASA Astrophysics Data System (ADS)

Kim, H.; Churilov, A.; Ciampi, G.; Cirignano, L.; Higgins, W.; Kim, S.; O'Dougherty, P.; Olschner, F.; Shah, Kanai

2011-02-01

Thallium bromide (TlBr) and related ternary compounds, TlBrI and TlBrCl, have been under development for room temperature gamma-ray spectroscopy due to high density, high Z and wide bandgap of the material. Low melting point and cubic crystal structure of selected compositions of these compounds facilitate crystal growth by melt techniques. Recent advances in material purification, crystal growth, and device processing have led to mobility-lifetime products of electrons in the mid 10 -3 cm 2/V range enabling working detectors of greater than 15 mm thickness to be fabricated. In this paper we report on our recent progress on TlBr detector development and first results from TlBr xCl 1- x devices. Pulse height spectra will be presented from TlBr arrays as thick as 18 mm. Depth corrected spectra will also be presented. For a 5 mm thick TlBr array, energy resolution of less than 1% (FWHM at 662 keV) was obtained after depth correction.

Preparation of superconductor precursor powders

DOEpatents

Bhattacharya, Raghunath; Blaugher, Richard D.

1995-01-01

A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals, such as nitrate salts of thallium, barium, calcium, and copper, which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of thallium in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

Resistance exercise-induced fluid shifts: change in active muscle size and plasma volume

NASA Technical Reports Server (NTRS)

Ploutz-Snyder, L. L.; Convertino, V. A.; Dudley, G. A.

1995-01-01

The purpose of this study was to test the hypothesis that the reduction in plasma volume (PV) induced by resistance exercise reflects fluid loss to the extravascular space and subsequently selective increase in cross-sectional area (CSA) of active but not inactive skeletal muscle. We compared changes in active and inactive muscle CSA and PV after barbell squat exercise. Magnetic resonance imaging (MRI) was used to quantify muscle involvement in exercise and to determine CSA of muscle groups or individual muscles [vasti (VS), adductor (Add), hamstring (Ham), and rectus femoris (RF)]. Muscle involvement in exercise was determined using exercise-induced contrast shift in spin-spin relaxation time (T2)-weighted MR images immediately postexercise. Alterations in muscle size were based on the mean CSA of individual slices. Hematocrit, hemoglobin, and Evans blue dye were used to estimate changes in PV. Muscle CSA and PV data were obtained preexercise and immediately postexercise and 15 and 45 min thereafter. A hierarchy of muscle involvement in exercise was found such that VS > Add > Ham > RF, with the Ham and RF showing essentially no involvement. CSA of the VS and Add muscle groups were increased 10 and 5%, respectively, immediately after exercise in each thigh with no changes in Ham and RF CSA. PV was decreased 22% immediately following exercise. The absolute loss of PV was correlated (r2 = 0.75) with absolute increase in muscle CSA immediately postexercise, supporting the notion that increased muscle size after resistance exercise reflects primarily fluid movement from the vascular space into active but not inactive muscle.

Exercise testing in asymptomatic severe aortic stenosis.

PubMed

Magne, Julien; Lancellotti, Patrizio; Piérard, Luc A

2014-02-01

The management and the clinical decision making in asymptomatic patients with aortic stenosis are challenging. An "aggressive" management, including early aortic valve replacement, is debated in these patients. However, the optimal timing for surgery remains controversial due to the lack of prospective data on the determinants of aortic stenosis progression, multicenter studies on risk stratification, and randomized studies on patient management. Exercise stress testing with or without imaging is strictly contraindicated in symptomatic patients with severe aortic stenosis. Exercise stress test is now recommended by current guidelines in asymptomatic patients and may provide incremental prognostic value. Indeed, the development of symptoms during exercise or an abnormal blood pressure response are associated with poor outcome and should be considered as an indication for surgery, as suggested by the most recently updated European Society of Cardiology 2012 guidelines. Exercise stress echocardiography may also improve the risk stratification and identify asymptomatic patients at higher risk of a cardiac event. When the test is combined with imaging, echocardiography during exercise should be recommended rather than post-exercise echocardiography. During exercise, an increase >18 to 20 mm Hg in mean pressure gradient, absence of improvement in left ventricular ejection fraction (i.e., absence of contractile reserve), and/or a systolic pulmonary arterial pressure >60 mm Hg (i.e., exercise pulmonary hypertension) are suggestive signs of advanced stages of the disease and impaired prognosis. Hence, exercise stress test may identify resting asymptomatic patients who develop exercise abnormalities and in whom surgery is recommended according to current guidelines. Exercise stress echocardiography may further unmask a subset of asymptomatic patients (i.e., without exercise stress test abnormalities) who are at high risk of reduced cardiac event free survival. In these patients, early surgery could be beneficial, whereas regular follow-up seems more appropriate in patients without echocardiographic abnormalities during exercise. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Attitudes and Barriers to Exercise in Adults with Type 1 Diabetes (T1DM) and How Best to Address Them: A Qualitative Study

PubMed Central

Lascar, Nadia; Kennedy, Amy; Hancock, Beverley; Jenkins, David; Andrews, Robert C.

2014-01-01

Background Regular physical activity has recognised health benefits for people with T1DM. However a significant proportion of them do not undertake the recommended levels of activity. Whilst questionnaire-based studies have examined barriers to exercise in people with T1DM, a formal qualitative analysis of these barriers has not been undertaken. Our aims were to explore attitudes, barriers and facilitators to exercise in patients with T1DM. Methodology A purposeful sample of long standing T1DM patients were invited to participate in this qualitative study. Twenty-six adults were interviewed using a semi-structured interview schedule to determine their level of exercise and barriers to initiation and maintenance of an exercise programme. Principal findings Six main barriers to exercise were identified: lack of time and work related factors; access to facilities; lack of motivation; embarrassment and body image; weather; and diabetes specific barriers (low levels of knowledge about managing diabetes and its complications around exercise). Four motivators to exercise were identified: physical benefits from exercise; improvements in body image; enjoyment and the social interaction of exercising at gym or in groups. Three facilitators to exercise were identified: free or reduced admission to gyms and pools, help with time management, and advice and encouragement around managing diabetes for exercise. Significance Many of the barriers to exercise in people with T1DM are shared with the non-diabetic population. The primary difference is the requirement for education about the effect of exercise on diabetes control and its complications. There was a preference for support to be given on a one to one basis rather than in a group environment. This suggests that with the addition of the above educational requirements, one to one techniques that have been successful in increasing activity in patients with other chronic disease and the general public should be successful in increasing activity in patients with T1DM. PMID:25237905

Attitudes and barriers to exercise in adults with type 1 diabetes (T1DM) and how best to address them: a qualitative study.

PubMed

Lascar, Nadia; Kennedy, Amy; Hancock, Beverley; Jenkins, David; Andrews, Robert C; Greenfield, Sheila; Narendran, Parth

2014-01-01

Regular physical activity has recognised health benefits for people with T1DM. However a significant proportion of them do not undertake the recommended levels of activity. Whilst questionnaire-based studies have examined barriers to exercise in people with T1DM, a formal qualitative analysis of these barriers has not been undertaken. Our aims were to explore attitudes, barriers and facilitators to exercise in patients with T1DM. A purposeful sample of long standing T1DM patients were invited to participate in this qualitative study. Twenty-six adults were interviewed using a semi-structured interview schedule to determine their level of exercise and barriers to initiation and maintenance of an exercise programme. Six main barriers to exercise were identified: lack of time and work related factors; access to facilities; lack of motivation; embarrassment and body image; weather; and diabetes specific barriers (low levels of knowledge about managing diabetes and its complications around exercise). Four motivators to exercise were identified: physical benefits from exercise; improvements in body image; enjoyment and the social interaction of exercising at gym or in groups. Three facilitators to exercise were identified: free or reduced admission to gyms and pools, help with time management, and advice and encouragement around managing diabetes for exercise. Many of the barriers to exercise in people with T1DM are shared with the non-diabetic population. The primary difference is the requirement for education about the effect of exercise on diabetes control and its complications. There was a preference for support to be given on a one to one basis rather than in a group environment. This suggests that with the addition of the above educational requirements, one to one techniques that have been successful in increasing activity in patients with other chronic disease and the general public should be successful in increasing activity in patients with T1DM.

Dynamic characteristics of T2*-weighted signal in calf muscles of peripheral artery disease during low-intensity exercise.

PubMed

Li, Zhijun; Muller, Matthew D; Wang, Jianli; Sica, Christopher T; Karunanayaka, Prasanna; Sinoway, Lawrence I; Yang, Qing X

2017-07-01

To evaluate the dynamic characteristics of T2* -weighted signal change in exercising skeletal muscle of healthy subjects and peripheral artery disease (PAD) patients under a low-intensity exercise paradigm. Nine PAD patients and nine age- and sex-matched healthy volunteers underwent a low-intensity exercise paradigm while magnetic resonance imaging (MRI) (3.0T) was obtained. T2*-weighted signal time-courses in lateral gastrocnemius, medial gastrocnemius, soleus, and tibialis anterior were acquired and analyzed. Correlations were performed between dynamic T2*-weighted signal and changes in heart rate, mean arterial pressure, leg pain, and perceived exertion. A significant signal decrease was observed during exercise in soleus and tibialis anterior of healthy participants (P = 0.0007-0.04 and 0.001-0.009, respectively). In PAD, negative signals were observed (P = 0.008-0.02 and 0.003-0.01, respectively) in soleus and lateral gastrocnemius during the early exercise stage. Then the signal gradually increased above the baseline in the lateral gastrocnemius during and after exercise in six of the eight patients who completed the study. This signal increase in patients' lateral gastrocnemius was significantly greater than in healthy subjects' during the later exercise stage (two-sample t-tests, P = 0.001-0.03). Heart rate and mean arterial pressure responses to exercise were significantly higher in PAD than healthy subjects (P = 0.036 and 0.008, respectively) and the patients experienced greater leg pain and exertion (P = 0.006 and P = 0.0014, respectively). During low-intensity exercise, there were different dynamic T2*-weighted signal behavior in the healthy and PAD exercising muscles. 2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:40-48. © 2016 International Society for Magnetic Resonance in Medicine.

Risk stratification for large artery or chronic coronary artery disease-related ischemic stroke in octogenarians undergoing exercise stress myocardial perfusion imaging: A cohort study.

PubMed

Katsikis, Athanasios; Theodorakos, Athanasios; Drosatos, Alexandros; Konstantinou, Konstantinos; Papaioannou, Spyridon; Koutelou, Maria

2017-04-01

To test, if in octogenarians, treadmill exercise with myocardial perfusion imaging (exercise-MPI) can risk stratify for large artery or chronic CAD-related ischemic stroke (LACCIS). Exercise-MPI-related data of 237 octogenarians (55% prior MI or revascularization) without previous stroke were registered and prospective follow-up was performed to document LACCIS. LACCIS was defined as acute onset of neurological symptoms with CT/MRI findings of non-lacunar-type infarcts in the absence of atrial fibrillation or intracardiac embolic sources. After 7.3 years, 10 LACCIS were documented. SSS [HR 1.08 (1.02-1.13 95% CIs), SDS [HR 1.1 (1.04-1.16 95% CIs)], and non-sustained VT or transient AV block during exercise [HR 3.9 (1.7-9.0 95% CIs)] were predictors of LACCIS (P < .01 for all). A SSS threshold of 16 had 81% specificity for identification of future LACCIS and risk groups formed according to this cut-off had significantly different LACCIS-free survival (P = .015). Exercise-MPI in octogenarians can provide risk stratification markers for LACCIS.

Advanced Digital Imaging Laboratory Using MATLAB® (Second edition)

NASA Astrophysics Data System (ADS)

Yaroslavsky, Leonid P.

2016-09-01

The first edition of this text book focussed on providing practical hands-on experience in digital imaging techniques for graduate students and practitioners keeping to a minimum any detailed discussion on the underlying theory. In this new extended edition, the author builds on the strength of the original edition by expanding the coverage to include formulation of the major theoretical results that underlie the exercises as well as introducing numerous modern concepts and new techniques. Whether you are studying or already using digital imaging techniques, developing proficiency in the subject is not possible without mastering practical skills. Including more than 100 MATLAB® exercises, this book delivers a complete applied course in digital imaging theory and practice. Part of IOP Series in Imaging Engineering Supplementary MATLAB codes and data files are available within Book Information.

Skin temperature evaluation by infrared thermography: Comparison of two image analysis methods during the nonsteady state induced by physical exercise

NASA Astrophysics Data System (ADS)

Formenti, Damiano; Ludwig, Nicola; Rossi, Alessio; Trecroci, Athos; Alberti, Giampietro; Gargano, Marco; Merla, Arcangelo; Ammer, Kurt; Caumo, Andrea

2017-03-01

The most common method to derive a temperature value from a thermal image in humans is the calculation of the average of the temperature values of all the pixels confined within a demarcated boundary defined region of interest (ROI). Such summary measure of skin temperature is denoted as Troi in this study. Recently, an alternative method for the derivation of skin temperature from the thermal image has been developed. Such novel method (denoted as Tmax) is based on an automated (software-driven) selection of the warmest pixels within the ROI. Troi and Tmax have been compared under basal, steady-state conditions, resulting very well correlated and characterized by a bias of approximately 1 °C (Tmax > Troi). Aim of this study was to investigate the relationship between Tmax and Troi under the nonsteady-state conditions induced by physical exercise. Thermal images of quadriceps of 13 subjects performing a squat exercise were recorded for 120 s before (basal steady state) and for 480 s after the initiation of the exercise (nonsteady state). The thermal images were then analysed to extract Troi and Tmax. Troi and Tmax changed almost in parallel during the nonstead -state. At a closer inspection, it was found that during the nonsteady state the bias between the two methods slightly increased (from 0.7 to 1.1 °C) and the degree of association between them slightly decreased (from Pearson's r = 0.96 to 0.83). Troi and Tmax had different relationships with the skin temperature histogram. Whereas Tmax was the mean, which could be interpreted as the centre of gravity of the histogram, Tmax was related with the extreme upper tail of the histogram. During the nonsteady state, the histogram increased its spread and became slightly more asymmetric. As a result, Troi deviated a little from the 50th percentile, while Tmax remained constantly higher than the 95th percentile. Despite their differences, Troi and Tmax showed a substantial agreement in assessing the changes in skin temperature following physical exercise. Further studies are needed to clarify the relationship existing among Tmax, Troi and cutaneous blood flow during physical exercise.

40 CFR 302.6 - Notification requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ash, bottom ash, and boiler slags), including the dumping and land spreading operations that occur..., bottom ash, and boiler slags. (d) Except for releases of radionuclides, notification of the release of an..., selenium, silver, thallium, or zinc is not required if the mean diameter of the particles released is...

Environmental factors determining the trace-level sorption of silver and thallium to soils.

PubMed

Jacobson, Astrid R; McBride, Murray B; Baveye, Philippe; Steenhuis, Tammo S

2005-06-01

Silver (Ag) and thallium (Tl) are nonessential elements that can be highly toxic to a number of biota even when present in the environment at trace levels. In spite of that, the literature on the chemistry and fate of Ag and Tl in soils is extremely scanty. In that context, the key objective of this research was to compare the sorption characteristics of trace amounts of Ag and Tl on a range of soils and minerals. A second objective was to determine the extent to which the composition and surface chemistry of the sorbents, as well as other environmental factors (simulated acid rain application and the presence of competing ions like K+ and NH4+) influence the sorption and lability of Ag and Tl. To this end, short-term and long-term sorption isotherms were generated under batch conditions for trace levels of Ag and Tl onto three illite-rich mineral soils from central New York (silt loam and fine sandy loam), a peaty-muck soil drained for agricultural use, and soil minerals (ferrihydrite and birnessite). Silver sorbed more strongly than thallium to all the soils. The peaty-muck soil sorbed Ag more strongly than the mineral soils, confirming that silver sorption to soils is dominated by soil organic matter either through exchange or complexation. The organic matter-rich soil's retention of Tl, however, was similar to that of the sandy soil. Amounts of Ag and Tl sorbed to the mineral soils increased after a 1-year incubation period. Whereas Ag sorption to the peaty-muck soil also increased with time, Tl sorption was unaffected. Short batch studies indicated that high amounts of Tl sorb to birnessite (30% by mass). However, subsequent X-ray diffraction (XRD) analysis of the solid did not detect the presence of any Tl3+ as Tl2O3 on the MnO4. In contrast, TlI was relatively poorly sorbed on noncrystalline ferrihydrite at pH 5.1 (1.5% by mass). Thus, Mn oxides may play a role in Tl retention by soils; whereas, contrary to previous reports, iron oxides do not effectively sorb Tl. Acid rain and addition of potassium (K+) and ammonium (NH4+) as competing ions had no long-term effect on Ag or Tl sorption. Thallium remaining in the all the batch sorption solutions, as determined by flame atomic absorption spectroscopy (FAAS) and differential pulse anodic stripping voltametry (DPASV), was completely labile, which may have important environmental consequences.

Source and distribution of sedimentary thallium in the Bohai Sea: Implications for hydrodynamic forces and anthropogenic impact

NASA Astrophysics Data System (ADS)

Hu, Ningjing; Liu, Jihua; Shi, Xuefa

2015-04-01

Source and distribution of sedimentary thallium in the Bohai Sea: Implications for hydrodynamic forces and anthropogenic impact Hu Ningjing, Liu Jihua, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Thallium (Tl), a non-essential and highly toxic trace metal, is listed as priority toxic pollutant by the United States Environmental Protection Agency (USEPA) (Keith and Telliard, 1979). However, its geochemical cycling in aquatic environment has received far less attention than that of many other trace metals. This has been attributed to relatively little commercial interest in Tl and, until recently, problems inherent in its detection at environmental concentrations (Meeravali and Jiang, 2008). In this study, we investigated the sources, distribution and fate of Tl in surface sediments of the Bohai Sea (BS), China, based on the datasets of total Tl and chemical speciation of Tl of 408 surface sediment samples in the total entire BS. The enrichment factors and chemical speciation of Tl indicated that Tl in BS was dominated by natural Tl, although anthropogenic Tl contamination was observed in the Liuguhe River mouth; the mud deposits are the sinks of Tl and the regional currents and tide systems play a key role on the accumulation of Tl in BS. The distribution of Tl consistent with that of MnO and Fe2O3 as well as the level of Fe-Mn fraction is relatively high, indicating MnO and Fe2O3 influence the geochemical behaviors of Tl in the BS. Although the positive correlation between Tl and TOC is observed for the samples in the BS, however, level of Tl in oxidizable faction could be neglected, suggesting TOC might not be a major factor affecting the concentration of Tl in BS. The low proportion of Tl in the non-residual fraction dominated by the Fe-Mn oxides suggested that the labile Tl was controlled by the Fe-Mn oxides and Tl has a low bioavailability and a minor potential threat to biota in BS. Acknowledgements: this work was jointly supported by National Natural Science Foundation of China (Grant Nos.41076032, 41276052 and 41376073) and the State Oceanic Administration, China (Grant No. 201105003). References Keith, L.H., Telliard, W.A., 1979. Priority pollutants-A perspective view. Environmental Science and Technology 13, 416-423. Meeravali, N.M., Jiang, S.-J., 2008. Ultra-trace speciation analysis of thallium in environmental water samples by inductively coupled plasma mass spectrometry after a novel sequential mixed-micelle cloud point extraction. Journal of Analytical Atomic Spectrometry 23, 555-560.

Magnetic resonance imaging of the rotator cuff muscles after baseball pitching.

PubMed

Yanagisawa, O; Niitsu, M; Takahashi, H; Itai, Y

2003-12-01

The purposes of present study were to investigate quantitatively using functional MR imaging the effect of a series of throwing activities on rotator cuff muscles and to compare the effect of pitching with that of all-out shoulder external rotator exercise as the targeted external rotator muscle group (the infraspinatus and the teres minor). MRI measurements after 135 baseball pitches or all-out shoulder external rotator exercise (concentric mode) in each subject's nondominant shoulder. 6 amateur baseball pitchers. serial T2-weighted images of rotator cuff muscles were obtained before pitching (or shoulder exercise) and immediately, 30, 60 min, 24, 48, 96 hrs after pitching (or shoulder exercise). T2 relaxation times (T2) at each measurement time were calculated for the rotator cuff muscles. Both the supraspinatus and the external rotator muscle group showed significant T2 elevations until 96 hrs after pitching. The subscapularis also showed significantly increased T2 until postpitching 48 hrs. On the other hand, a significant T2 elevation continued until 60 min after shoulder exercise, but thereafter returned towards the value at rest over the next 24 hrs. Long lasting T2 elevations in rotator cuff muscles would be associated with an increase in each intramuscular water content, and may be attributed to the muscle damage that resulted from eccentric contraction during pitching. This information should serve as a useful complement to shoulder injury prevention for baseball pitchers.

Added prognostic value of ischaemic threshold in radionuclide myocardial perfusion imaging: a common-sense integration of exercise tolerance and ischaemia severity.

PubMed

Marini, Cecilia; Acampa, Wanda; Bauckneht, Matteo; Daniele, Stefania; Capitanio, Selene; Cantoni, Valeria; Fiz, Francesco; Zampella, Emilia; Dib, Bassam; Assante, Roberta; Bruzzi, Paolo; Sambuceti, Gianmario; Cuocolo, Alberto

2015-04-01

Reversible ischaemia at radionuclide myocardial perfusion imaging (MPI) accurately predicts risk of cardiac death and nonfatal myocardial infarction (major adverse cardiac events, MACE). This prognostic penetrance might be empowered by accounting for exercise tolerance as an indirect index of ischaemia severity. The present study aimed to verify this hypothesis integrating imaging assessment of ischaemia severity with exercise maximal rate pressure product (RPP) in a large cohort of patients with suspected or known coronary artery disease (CAD). We analysed 1,502 consecutive patients (1,014 men aged 59 ± 10 years) submitted to exercise stress/rest MPI. To account for exercise tolerance, the summed difference score (SDS) was divided by RPP at tracer injection providing a clinical prognostic index (CPI). Reversible ischaemia was documented in 357 patients (24 %) and was classified by SDS as mild (SDS 2-4) in 180, moderate (SDS 5-7) in 118 and severe (SDS >7) in 59. CPI values of ischaemic patients were clustered into tertiles with lowest and highest values indicating low and high risk, respectively. CPI modified SDS risk prediction in 119/357 (33 %) patients. During a 60-month follow-up, MACE occurred in 68 patients. Kaplan-Meier analysis revealed that CPI significantly improved predictive power for MACE incidence with respect to SDS alone. Multivariate Cox analysis confirmed the additive independent value of CPI-derived information. Integration of ischaemic threshold and ischaemia extension and severity can improve accuracy of exercise MPI in predicting long-term outcome in a large cohort of patients with suspected or known CAD.

Noninvasive analysis of human neck muscle function

NASA Technical Reports Server (NTRS)

Conley, M. S.; Meyer, R. A.; Bloomberg, J. J.; Feeback, D. L.; Dudley, G. A.

1995-01-01

STUDY DESIGN. Muscle use evoked by exercise was determined by quantifying shifts in signal relaxation times of T2-weighted magnetic resonance images. Images were collected at rest and after exercise at each of two intensities (moderate and intense) for each of four head movements: 1) extension, 2) flexion, 3) rotation, and 4) lateral flexion. OBJECTIVE. This study examined the intensity and pattern of neck muscle use evoked by various movements of the head. The results will help elucidate the pathophysiology, and thus methods for treating disorders of the cervical musculoskeletal system. SUMMARY OF BACKGROUND DATA. Exercise-induced contrast shifts in T2 has been shown to indicate muscle use during the activity. The noninvasive nature of magnetic resonance imaging appears to make it an ideal approach for studying the function of the complex neuromuscular system of the neck. METHODS. The extent of T2 increase was examined to gauge how intensely nine different neck muscles or muscle pairs were used in seven subjects. The absolute and relative cross-sectional area of muscle showing a shift in signal relaxation was assessed to infer the pattern of use among and within individual neck muscles or muscle pairs. RESULTS. Signal relaxation increased with exercise intensity for each head movement. The absolute and relative cross-sectional area of muscle showing a shift in signal relaxation also increased with exercise load. Neck muscles or muscle pairs extensively used to perform each head movement were: extension--semispinalis capitis and cervicis and splenius capitis; flexion--sternocleidomastoid and longus capitis and colli; rotation--splenius capitis, levator scapulae, scalenus, semispinalis capitis ipsilateral to the rotation, and sternocleidomastoid contralateral; and lateral flexion--sternocleidomastoid CONCLUSION. The results of this study, in part, agree with the purported functions of neck muscles derived from anatomic location. This also was true for the few selected muscles that have been examined in human electromyographic studies. Neck muscle function and morphology can be studied at a detailed level using exercise-induced shifts in magnetic resonance images.

Motion-compensated noncontact imaging photoplethysmography to monitor cardiorespiratory status during exercise

NASA Astrophysics Data System (ADS)

Sun, Yu; Hu, Sijung; Azorin-Peris, Vicente; Greenwald, Stephen; Chambers, Jonathon; Zhu, Yisheng

2011-07-01

With the advance of computer and photonics technology, imaging photoplethysmography [(PPG), iPPG] can provide comfortable and comprehensive assessment over a wide range of anatomical locations. However, motion artifact is a major drawback in current iPPG systems, particularly in the context of clinical assessment. To overcome this issue, a new artifact-reduction method consisting of planar motion compensation and blind source separation is introduced in this study. The performance of the iPPG system was evaluated through the measurement of cardiac pulse in the hand from 12 subjects before and after 5 min of cycling exercise. Also, a 12-min continuous recording protocol consisting of repeated exercises was taken from a single volunteer. The physiological parameters (i.e., heart rate, respiration rate), derived from the images captured by the iPPG system, exhibit functional characteristics comparable to conventional contact PPG sensors. Continuous recordings from the iPPG system reveal that heart and respiration rates can be successfully tracked with the artifact reduction method even in high-intensity physical exercise situations. The outcome from this study thereby leads to a new avenue for noncontact sensing of vital signs and remote physiological assessment, with clear applications in triage and sports training.

40 CFR Appendix A to Subpart O of... - Regulated Contaminants

Code of Federal Regulations, 2013 CFR

2013-07-01

... provide a medium for microbial growth. Turbidity may indicate the presence of disease-causing organisms... containing selenium in excess of the MCL over many years could experience hair or fingernail losses, numbness... water containing thallium in excess of the MCL over many years could experience hair loss, changes in...

40 CFR Appendix A to Subpart O of... - Regulated Contaminants

Code of Federal Regulations, 2011 CFR

2011-07-01

... provide a medium for microbial growth. Turbidity may indicate the presence of disease-causing organisms... containing selenium in excess of the MCL over many years could experience hair or fingernail losses, numbness... water containing thallium in excess of the MCL over many years could experience hair loss, changes in...

40 CFR Appendix A to Subpart O of... - Regulated Contaminants

Code of Federal Regulations, 2012 CFR

2012-07-01

... provide a medium for microbial growth. Turbidity may indicate the presence of disease-causing organisms... containing selenium in excess of the MCL over many years could experience hair or fingernail losses, numbness... water containing thallium in excess of the MCL over many years could experience hair loss, changes in...

40 CFR Appendix A to Subpart O of... - Regulated Contaminants

Code of Federal Regulations, 2014 CFR

2014-07-01

... provide a medium for microbial growth. Turbidity may indicate the presence of disease-causing organisms... containing selenium in excess of the MCL over many years could experience hair or fingernail losses, numbness... water containing thallium in excess of the MCL over many years could experience hair loss, changes in...

Fabrication of Tl2Ba2CaCu2O8 superconducting films without thallium pellets

NASA Astrophysics Data System (ADS)

Xu, Teng-Da; Xing, Jian; Wang, Li-Tian; Zhang, Jin-Li; Zhao, Sheng-Hui; Xiong, Yang; Zhao, Xin-Jie; Ji, Lu; Zhang, Xu; He, Ming

2018-05-01

Not Available Project supported by the National Natural Science Foundation of China (Grant No. 51002081), the Fundamental Research Funds for the Central Universities, China, and the Research Program of Application Foundation and Advanced Technology of Tianjin, China (Grant No. 15JCQNJC01300).

40 CFR 302.6 - Notification requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... transportation of coal and coal ash (including fly ash, bottom ash, and boiler slags), including the dumping and... coal and coal ash, including fly ash, bottom ash, and boiler slags. (d) Except for releases of..., chromium, copper, lead, nickel, selenium, silver, thallium, or zinc is not required if the mean diameter of...

The effects of acute exercise on attentional bias towards smoking-related stimuli during temporary abstinence from smoking.

PubMed

Van Rensburg, Kate Janse; Taylor, Adrian; Hodgson, Tim

2009-11-01

Attentional bias towards smoking-related cues is increased during abstinence and can predict relapse after quitting. Exercise has been found to reduce cigarette cravings and desire to smoke during temporary abstinence and attenuate increased cravings in response to smoking cues. To assess the acute effects of exercise on attentional bias to smoking-related cues during temporary abstinence from smoking. In a randomized cross-over design, on separate days regular smokers (n = 20) undertook 15 minutes of exercise (moderate intensity stationary cycling) or passive seating following 15 hours of nicotine abstinence. Attentional bias was measured at baseline and post-treatment. The percentage of dwell time and direction of initial fixation was assessed during the passive viewing of a series of paired smoking and neutral images using an Eyelink II eye-tracking system. Self-reported desire to smoke was recorded at baseline, mid- and post-treatment and post-eye-tracking task. There was a significant condition x time interaction for desire to smoke, F((1,18)) = 10.67, P = 0.004, eta(2) = 0.36, with significantly lower desire to smoke at mid- and post-treatment following the exercise condition. The percentage of dwell time and direction of initial fixations towards smoking images were also reduced significantly following the exercise condition compared with the passive control. Findings support previous research that acute exercise reduces desire to smoke. This is the first study to show that exercise appears to also influence the salience and attentional biases towards cigarettes.

Middle cerebral artery diameter changes during rhythmic handgrip exercise in humans.

PubMed

Verbree, J; Bronzwaer, Agt; van Buchem, M A; Daemen, Mjap; van Lieshout, J J; van Osch, Mjp

2017-08-01

Transcranial Doppler (TCD) sonography is a frequently employed technique for quantifying cerebral blood flow by assuming a constant arterial diameter. Given that exercise increases arterial pressure by sympathetic activation, we hypothesized that exercise might induce a change in the diameter of large cerebral arteries. Middle cerebral artery (MCA) cross-sectional area was assessed in response to handgrip exercise by direct magnetic resonance imaging (MRI) observations. Twenty healthy subjects (11 female) performed three 5 min bouts of rhythmic handgrip exercise at 60% maximum voluntary contraction, alternated with 5 min of rest. High-resolution 7 T MRI scans were acquired perpendicular to the MCA. Two blinded observers manually determined the MCA cross-sectional area. Sufficient image quality was obtained in 101 MCA-scans of 19 subjects (age-range 20-59 years). Mixed effects modelling showed that the MCA cross-sectional area decreased by 2.1 ± 0.8% (p = 0.01) during handgrip, while the heart rate increased by 11 ± 2% (p < 0.001) at constant end-tidal CO 2 (p = 0.10). In conclusion, the present study showed a 2% decrease in MCA cross-sectional area during rhythmic handgrip exercise. This further strengthens the current concept of sympathetic control of large cerebral arteries, showing in vivo vasoconstriction during exercise-induced sympathetic activation. Moreover, care must be taken when interpreting TCD exercise studies as diameter constancy cannot be assumed.

A prognostic scoring system for arm exercise stress testing.

PubMed

Xie, Yan; Xian, Hong; Chandiramani, Pooja; Bainter, Emily; Wan, Leping; Martin, Wade H

2016-01-01

Arm exercise stress testing may be an equivalent or better predictor of mortality outcome than pharmacological stress imaging for the ≥50% for patients unable to perform leg exercise. Thus, our objective was to develop an arm exercise ECG stress test scoring system, analogous to the Duke Treadmill Score, for predicting outcome in these individuals. In this retrospective observational cohort study, arm exercise ECG stress tests were performed in 443 consecutive veterans aged 64.1 (11.1) years. (mean (SD)) between 1997 and 2002. From multivariate Cox models, arm exercise scores were developed for prediction of 5-year and 12-year all-cause and cardiovascular mortality and 5-year cardiovascular mortality or myocardial infarction (MI). Arm exercise capacity in resting metabolic equivalents (METs), 1 min heart rate recovery (HRR) and ST segment depression ≥1 mm were the stress test variables independently associated with all-cause and cardiovascular mortality by step-wise Cox analysis (all p<0.01). A score based on the relation HRR (bpm)+7.3×METs-10.5×ST depression (0=no; 1=yes) prognosticated 5-year cardiovascular mortality with a C-statistic of 0.81 before and 0.88 after adjustment for significant demographic and clinical covariates. Arm exercise scores for the other outcome end points yielded C-statistic values of 0.77-0.79 before and 0.82-0.86 after adjustment for significant covariates versus 0.64-0.72 for best fit pharmacological myocardial perfusion imaging models in a cohort of 1730 veterans who were evaluated over the same time period. Arm exercise scores, analogous to the Duke Treadmill Score, have good power for prediction of mortality or MI in patients who cannot perform leg exercise.

Trends in referral patterns, invasive management, and mortality in elderly patients referred for exercise stress testing.

PubMed

Bouzas-Mosquera, Alberto; Peteiro, Jesús; Broullón, Francisco J; Calviño-Santos, Ramón; Mosquera, Víctor X; Barbeito-Caamaño, Cayetana; Larrañaga-Moreira, José María; Maneiro-Melón, Nicolás; Álvarez-García, Nemesio; Vázquez-Rodríguez, José Manuel

2015-12-01

Scarce data are available on the temporal patterns in clinical characteristics and outcomes of elderly patients referred for exercise stress testing. We aimed to assess the trends in baseline characteristics, tests results, referrals for invasive management, and mortality in these patients. We evaluated 11,192 patients aged ≥65years who were referred for exercise stress testing between January 1998 and December 2013. Calendar years were grouped into four quadrennia (1998-2001, 2002-2005, 2006-2009, and 2010-2013), and trends in clinical characteristics of the patients, type and results of the tests, referrals for invasive management, and mortality across the different periods were assessed. Despite a progressive decrease in the proportion of patients with non-interpretable baseline electrocardiograms or prior history of coronary artery disease, there was a gradual and marked increase in the use of cardiac imaging from 32.8% in 1998-2001 to 67.6% in 2010-2013 (p<0.001). In addition, despite a gradual decline in the probability of positive exercise stress testing both without imaging (from 18.9 to 13.6%, p<0.001) and with imaging assessment (from 40.2 to 29.7%, p<0.001), the cumulative rate of coronary revascularization at 1year increased (from 10.8 to 13.7%, p<0.001). One-year mortality also decreased progressively from 3% to 1.6% (p<0.001). Among older adults referred for exercise stress testing, we observed a decline over time in the probability of inducible myocardial ischemia, an increase in the use of cardiac imaging and in the rate of coronary revascularization, and an improvement in the survival rate at 1year. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Cardiac investigation in patients with diabetes.

PubMed

Tardif, Jean-Claude

2006-02-01

Most patients with type 2 diabetes die from heart disease. Screening for the presence of myocardial ischemia is of clinical importance in the management of this population. The pain response to ischemia can be either absent or blunted in diabetes, resulting in the absence of symptoms or an atypical presentation. Exercise electrocardiogram (ECG) should be the initial test in men who are able to exercise and have a normal resting ECG. Stress cardiac imaging should be the initial test in diabetic men with an abnormal resting ECG or who are not able to exercise. More widespread use of cardiac imaging is probably justified in diabetic women and patients with suspected coronary artery disease. Official guidelines for appropriate and cost-effective cardiac investigation should help physicians manage diabetic patients.

In vivo nuclear magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Leblanc, A.

1986-05-01

During the past year the Woodlands Baylor Magnetic Resonance Imaging (MRI) facility became fully operational. A detailed description of this facility is given. One significant instrument addition this year was the 100 MHz, 40cm bore superconducting imaging spectrometer. This instrument gives researchers the capability to acquire high energy phosphate spectra. This will be used to investigate ATP, phosphocreatinine and inorganic phosphate changes in normal and atrophied muscle before, during and after exercise. An exercise device for use within the bore of the imaging magnet is under design/construction. The results of a study of T sub 1 and T sub 2 changes in atrophied muscle in animals and human subjects are given. The imaging and analysis of the lower leg of 15 research subjects before and after 5 weeks of complete bedrest was completed. A compilation of these results are attached.

In vivo nuclear magnetic resonance imaging

NASA Technical Reports Server (NTRS)

Leblanc, A.

1986-01-01

During the past year the Woodlands Baylor Magnetic Resonance Imaging (MRI) facility became fully operational. A detailed description of this facility is given. One significant instrument addition this year was the 100 MHz, 40cm bore superconducting imaging spectrometer. This instrument gives researchers the capability to acquire high energy phosphate spectra. This will be used to investigate ATP, phosphocreatinine and inorganic phosphate changes in normal and atrophied muscle before, during and after exercise. An exercise device for use within the bore of the imaging magnet is under design/construction. The results of a study of T sub 1 and T sub 2 changes in atrophied muscle in animals and human subjects are given. The imaging and analysis of the lower leg of 15 research subjects before and after 5 weeks of complete bedrest was completed. A compilation of these results are attached.

A Self-determination Theory approach to the study of body image concerns, self-presentation and self-perceptions in a sample of aerobic instructors.

PubMed

Thøgersen-Ntoumani, Cecilie; Ntoumanis, Nikos

2007-03-01

This study examined motivational predictors of body image concerns, self-presentation and self-perceptions using Self-determination Theory as a guiding framework. Aerobic instructors (N = 149) completed questionnaires measuring general need satisfaction, exercise motivational regulations, body image concerns, social physique anxiety and self-perceptions. Introjected regulation predicted all outcome variables in the expected direction. Intrinsic motivation positively predicted physical self-worth. Further, autonomy need satisfaction negatively predicted body image concerns. Finally, differences existed in need satisfaction, introjected regulation, self-perceptions and social physique anxiety between those at risk of developing eating disorders and those not at risk. The results underline the importance of overall and exercise-specific feelings of self-determination in dealing with body image concerns and low self-perceptions of aerobics instructors.

Intrinsic Foot Muscle Activation During Specific Exercises: A T2 Time Magnetic Resonance Imaging Study.

PubMed

Gooding, Thomas M; Feger, Mark A; Hart, Joseph M; Hertel, Jay

2016-08-01

The intrinsic foot muscles maintain the medial longitudinal arch and aid in force distribution and postural control during gait. Impaired intrinsic foot-muscle function has been linked to various foot conditions. Several rehabilitative exercises have been proposed to improve it; however, literature that identifies which individual muscles are activated during specific intrinsic foot-muscle exercises is lacking. To describe changes in activation of the intrinsic plantar foot muscles after 4 exercises as measured with T2 magnetic resonance imaging (MRI). Descriptive laboratory study. Research laboratory. Eight healthy National Collegiate Athletic Association Division I collegiate cross-country and track athletes (5 men and 3 women: age = 20 ± 0.93 years, height = 180.98 ± 10.84 cm, mass = 70.91 ± 7.82 kg). Participants underwent T2 MRI before and after each exercise. They completed 1 set of 40 repetitions of each exercise (short-foot exercise, toes spread out, first-toe extension, second- to fifth-toes extension). Percentage increases in muscle activation of the abductor hallucis, flexor digitorum brevis, abductor digiti minimi, quadratus plantae, flexor digiti minimi, adductor hallucis oblique, flexor hallucis brevis, and interossei and lumbricals (analyzed together) after each exercise were assessed using T2 MRI. All muscles showed increased activation after all exercises. The mean percentage increase in activation ranged from 16.7% to 34.9% for the short-foot exercise, 17.3% to 35.2% for toes spread out, 13.1% to 18.1% for first-toe extension, and 8.9% to 22.5% for second- to fifth-toes extension. All increases in activation had associated 95% confidence intervals that did not cross zero. Each of the 4 exercises was associated with increased activation in all of the plantar intrinsic foot muscles evaluated. These results may have clinical implications for the prescription of specific exercises to target individual intrinsic foot muscles.

Geometrical Meaning of Arithmetic Series [Image Omitted], [Image Omitted] and [Image Omitted] in Terms of the Elementary Combinatorics

ERIC Educational Resources Information Center

Kobayashi, Yukio

2011-01-01

The formula [image omitted] is closely related to combinatorics through an elementary geometric exercise. This approach can be expanded to the formulas [image omitted], [image omitted] and [image omitted]. These formulas are also nice examples of showing two approaches, one algebraic and one combinatoric, to a problem of counting. (Contains 6…

Exercise dependence and muscle dysmorphia in novice and experienced female bodybuilders.

PubMed

Hale, Bruce D; Diehl, Danielle; Weaver, Krista; Briggs, Michael

2013-12-01

Extensive research has shown that male bodybuilders are at high risk for exercise dependence, but few studies have measured these variables in female bodybuilders. Prior research has postulated that muscular dysmorphia was more prevalent in men than women, but several qualitative studies of female bodybuilders have indicated that female bodybuilders show the same body image concerns. Only one study has compared female bodybuilders with control recreational female lifters on eating behaviors, body image, shape pre-occupation, body dissatisfaction, and steroid use. The purpose of this study was to compare exercise dependence and muscle dysmorphia measures between groups of female weight lifters. Seventy-four female lifters were classified into three lifting types (26 expert bodybuilders, 10 or more competitions; 29 novice bodybuilders, 3 or less competitions; and 19 fitness lifters, at least 6 months prior lifting) who each completed a demographic questionnaire, the Exercise Dependence Scale (EDS), the Drive for Thinness scale (DFT) of the Eating Disorder Inventory-2, the Bodybuilding Dependence Scale (BDS), and the Muscle Dysmorphia Inventory (MDI). Female bodybuilders scored higher than fitness lifters for EDS Total, BDS Training and Social Dependence, and on Supplement Use, Dietary Behavior, Exercise Dependence, and Size Symmetry scales of the MDI. Female bodybuilders seem to be more at risk for exercise dependence and muscle dysmorphia symptoms than female recreational weight lifters.

Stimulated echo diffusion tensor imaging and SPAIR T2-weighted imaging in Chronic Exertional Compartment Syndrome of the lower leg muscles

PubMed Central

Sigmund, Eric E.; Sui, Dabang; Ukpebor, Obehi; Baete, Steven; Fieremans, Els; Babb, James S.; Mechlin, Michael; Liu, Kecheng; Kwon, Jane; Mcgorty, KellyAnne; Hodnett, Phil; Bencardino, Jenny

2013-01-01

Purpose To evaluate the performance of diffusion tensor imaging (DTI) in the evaluation of chronic exertional compartment syndrome (CECS) as compared to T2-weighted imaging. Materials and Methods Using an IRB-approved HIPAA-compliant protocol, spectral adiabatic inversion recovery (SPAIR) T2-weighted imaging (T2w) and stimulated echo DTI were applied to 8 healthy volunteers and 14 suspected CECS patients before and after exertion. Longitudinal and transverse diffusion eigenvalues, mean diffusivity (MD), and fractional anisotropy (FA) were measured in 7 calf muscle compartments, which in patients were classified by their response on T2w: normal (<20% change), and CECS (>20% change). Mixed model analysis of variance compared subject groups and compartments in terms of response factors (post-/pre-exercise ratios) of DTI parameters. Results All diffusivities significantly increased (p<0.0001) and FA decreased (p=.0014) with exercise. Longitudinal diffusion responses were significantly smaller than transversal diffusion responses (p<0.0001). 19 of 98 patient compartments were classified as CECS on T2w. MD increased by 3.8±3.4% (volunteer), 7.4±4.2 % (normal), and 9.1±7.0% (CECS) with exercise. Conclusion DTI shows promise as an ancillary imaging method in the diagnosis and understanding of the pathophysiology in CECS. Future studies may explore its utility in predicting response to treatment. PMID:23440764

Attitudes of overweight and normal weight adults regarding exercise at a health club.

PubMed

Miller, Wayne C; Miller, Todd A

2010-01-01

To compare attitudes of overweight (OW) and normal weight (NW) adults regarding health club exercise. A 46-item survey (23 pairs of attitude/value statements) measured attitudes toward exercising at a health club 30 minutes, twice a week, for a month. Survey posted on surveymonkey.com. Respondents (men = 730, women = 822). Attitudes toward exercise, exercise intent. t tests, Mann-Whitney rank sum, 2-way analysis of variance, Pearson rank correlations. Significance set at P < .05. More than NW, OW believe exercise improves appearance (P < .001) and self image (P < .03). OW feel more embarrassed and intimidated about exercising, exercising around young people, exercising around fit people, and about health club salespeople than NW (P < .001). OW and NW feel the same about exercising with the opposite sex, complicated exercise equipment, exercise boredom, and intention to exercise. Age rather than weight affects exercise intent. OW Caucasians (C) have less exercise intent than OW non-C. OW women are more embarrassed about exercising than NW women and OW men. The heavier the subject's weight, the lower his or her perception of health (r = -0.53, P < .001). Increasing the OW person's positive beliefs while decreasing negative beliefs about health club exercise will improve his or her intent to exercise at a health club.

False-positive defects on exercise 99mTc-sestamibi SPECT imaging, but not on dipyridamole 99mTc-sestamibi SPECT imaging, in a patient with right bundle branch block (RBBB).

PubMed

Javadi, Hamid; Jallalat, Sara; Semnani, Shahriar; Mogharrabi, Mehdi; Nabipour, Iraj; Abbaszadeh, Moloud; Assadi, Majid

2013-01-01

False-positive findings with myocardial perfusion imaging (MPI) have frequently been identified in the presence of left bundle branch block (LBBB) and tend to lower the accuracy of MPI in individuals with normal coronary angiographs. Pharmacologic stress is recognized as the preferred method for MPI in patients with LBBB. In contrast, very few studies have evaluated the effect of right bundle branch block (RBBB) on MPI, and there is no consensus regarding the selection of pharmacologic versus exercise stress during MPI for the RBBB patient. In this study, we present a 45-year-old man with RBBB, who has a normal coronary artery angiography, but who showed abnormal myocardial perfusion with exercise MPI, and normal perfusion on dipyridamole MPI. The aim of the study is to stimulate awareness that the stress method selected for patients with RBBB can potentially interfere with the accuracy of the data.

A pilot study: a descriptive correlational study of factors associated with weight in college nursing students.

PubMed

Singleton, Enrica Kinchen; Bienemy, Cynthia; Hutchinson, Sharon W; Dellinger, Amy; Rami, Janet S

2011-01-01

From a convenience sample consisting of junior level nursing students enrolled in a research class at a southern Historically Black College and University (HBCU), this pilot study investigated the percent of participants who were overweight as determined by Body Mass Index (BMI) measurements, and the percent satisfied with their body image as measured by the Strunkard Body Image Scale. BMI measurements were correlated with self esteem, body image, self care, and self efficacy in the regulation of eating habits and exercise regimens. The study found that students with greater BMIs had lower self efficacy beliefs about regulating their exercise habits. Self care, post the self directed intervention, significantly correlated with the pre and post intervention scores of self efficacy to regulate exercise, and with the post intervention scores of self efficacy to regulate eating habits. However, the study found that students' self care capacity was significantly different at the end of the study period.

Detection of ultrastructural changes in genetically altered and exercised skeletal muscle using PS-OCT

NASA Astrophysics Data System (ADS)

Pasquesi, James J.; Schlachter, Simon C.; Boppart, Marni D.; Chaney, Eric; Kaufman, Stephen J.; Boppart, Stephen A.

2006-02-01

Birefringence of skeletal muscle has been associated with the ultrastructure of individual sarcomeres, specifically the arrangement of A-bands corresponding to the thick myosin filaments. Murine skeletal muscle (gastrocnemius) was imaged with a fiber-based PS-OCT imaging system to determine the level of birefringence present in the tissue under various conditions. In addition to muscle controls from wild-type mice, muscle from abnormal mice included: genetically-modified (mdx) mice which model human muscular dystrophy, transgenic mice exhibiting an overexpression of integrin (α7β1), and transgenic integrin (α7β1)knockout mice. Comparisons were also made between rested and exercised muscles to determine the effects of exercise on muscle birefringence for each of these normal and abnormal conditions. The PS-OCT images revealed that the presence of birefringence was similar in the rested muscle with dystrophy-like features (i.e., lacking the structural protein dystrophin - mdx) and in the integrin (α7β1)knockout muscle when compared to the normal (wild-type) control. However, exercising these abnormal muscle tissues drastically reduced the presence of birefringence detected by the PS-OCT system. The muscle exhibiting an overexpression of integrin (α7β1) remained heavily birefringent before and after exercise, similar to the normal (wild-type) muscle. These results suggest that there is a distinct relationship between the degree of birefringence detected using PS-OCT and the sarcomeric ultrastructure present within skeletal muscle.

Non-invasive assessment of low- and intermediate-risk patients with chest pain

PubMed Central

Balfour, Pelbreton C.; Gonzalez, Jorge A.; Kramer, Christopher M.

2016-01-01

Coronary artery disease (CAD) remains a significant global public health burden despite advancements in prevention and therapeutic strategies. Common non-invasive imaging modalities, anatomic and functional, are available for the assessment of patients with stable chest pain. Exercise electrocardiography is a long-standing method for evaluation for CAD and remains the initial test for the majority of patients who can exercise adequately with a baseline interpretable electrocardiogram. The addition of cardiac imaging to exercise testing provides incremental benefit for accurate diagnosis for CAD and is particularly useful in patients who are unable to exercise adequately and/or have uninterpretable electrocardiograms. Radionuclide myocardial perfusion imaging and echocardiography with exercise or pharmacological stress provide high sensitivity and specificity in the detection and further risk stratification of patients with CAD. Recently, coronary computed tomography angiography has demonstrated its growing role to rule out significant CAD given its high negative predictive value. Although less available, stress cardiac magnetic resonance provides a comprehensive assessment of cardiac structure and function and provides a high diagnostic accuracy in the detection of CAD. The utilization of non-invasive testing is complex due to various advantages and limitations, particularly in the assessment of low- and intermediate-risk patients with chest pain, where no single study is suitable for all patients. This review will describe currently available non-invasive modalities, along with current evidence-based guidelines and appropriate use criteria in the assessment of low- and intermediate-risk patients with suspected, stable CAD. PMID:27717538

Exercise Sensing and Pose Recovery Inference Tool (ESPRIT) - A Compact Stereo-based Motion Capture Solution For Exercise Monitoring

NASA Technical Reports Server (NTRS)

Lee, Mun Wai

2015-01-01

Crew exercise is important during long-duration space flight not only for maintaining health and fitness but also for preventing adverse health problems, such as losses in muscle strength and bone density. Monitoring crew exercise via motion capture and kinematic analysis aids understanding of the effects of microgravity on exercise and helps ensure that exercise prescriptions are effective. Intelligent Automation, Inc., has developed ESPRIT to monitor exercise activities, detect body markers, extract image features, and recover three-dimensional (3D) kinematic body poses. The system relies on prior knowledge and modeling of the human body and on advanced statistical inference techniques to achieve robust and accurate motion capture. In Phase I, the company demonstrated motion capture of several exercises, including walking, curling, and dead lifting. Phase II efforts focused on enhancing algorithms and delivering an ESPRIT prototype for testing and demonstration.

Addition of atropine to submaximal exercise stress testing in patients evaluated for suspected ischaemia with SPECT imaging: a randomized, placebo-controlled trial.

PubMed

Manganelli, Fiore; Spadafora, Marco; Varrella, Paola; Peluso, Giuseppina; Sauro, Rosario; Di Lorenzo, Emilio; Rosato, Giuseppe; Daniele, Stefania; Cuocolo, Alberto

2011-02-01

To evaluate the effects of the addition of atropine to exercise testing in patients who failed to achieve their target heart rate (HR) during stress myocardial perfusion imaging with single-photon emission computed tomography (SPECT). The study was a prospective, randomized, placebo-controlled design. Patients with suspected or known coronary artery disease who failed to achieve a target HR (≥85% of maximal predicted HR) during exercise SPECT imaging were randomized to receive intravenous atropine (n=100) or placebo (n=101). The two groups of patients did not differ with respect to demographic or clinical characteristics. A higher proportion of patients in the atropine group achieved the target HR compared to the placebo group (60% versus 3%, p<0.0001). SPECT imaging was abnormal in a higher proportion of patients in the atropine group as compared to the placebo group (57% versus 42%, p<0.05). Stress-induced myocardial ischaemia was present in more patients in the atropine group as compared to placebo (47% versus 29%, p<0.01). In both groups of patients, no major side effects occurred. The addition of atropine at the end of exercise testing is more effective than placebo in raising HR to adequate levels, without additional risks of complications. The use of atropine in patients who initially failed to achieve their maximal predicted HR is associated with a higher probability of achieving a diagnostic myocardial perfusion study.

Dose-response effects of aerobic exercise on estrogen among women at high risk for breast cancer: a randomized controlled trial.

PubMed

Schmitz, Kathryn H; Williams, Nancy I; Kontos, Despina; Domchek, Susan; Morales, Knashawn H; Hwang, Wei-Ting; Grant, Lorita L; DiGiovanni, Laura; Salvatore, Domenick; Fenderson, Desire'; Schnall, Mitchell; Galantino, Mary Lou; Stopfer, Jill; Kurzer, Mindy S; Wu, Shandong; Adelman, Jessica; Brown, Justin C; Good, Jerene

2015-11-01

Medical and surgical interventions for elevated breast cancer risk (e.g., BRCA1/2 mutation, family history) focus on reducing estrogen exposure. Women at elevated risk may be interested in less aggressive approaches to risk reduction. For example, exercise might reduce estrogen, yet has fewer serious side effects and less negative impact than surgery or hormonal medications. Randomized controlled trial. Increased risk defined by risk prediction models or BRCA mutation status. Eligibility: Age 18-50, eumenorrheic, non-smokers, and body mass index (BMI) between 21 and 50 kg/m(2). 139 were randomized. Treadmill exercise: 150 or 300 min/week, five menstrual cycles. Control group maintained exercise <75 min/week. Area under curve (AUC) for urinary estrogen. Secondary measures: urinary progesterone, quantitative digitized breast dynamic contrast-enhanced magnetic resonance imaging background parenchymal enhancement. Mean age 34 years, mean BMI 26.8 kg/m(2). A linear dose-response relationship was observed such that every 100 min of exercise is associated with 3.6 % lower follicular phase estrogen AUC (linear trend test, p = 0.03). No changes in luteal phase estrogen or progesterone levels. There was also a dose-response effect noted: for every 100 min of exercise, there was a 9.7 % decrease in background parenchymal enhancement as measured by imaging (linear trend test, p = 0.009). Linear dose-response effect observed to reduce follicular phase estrogen exposure measured via urine and hormone sensitive breast tissue as measured by imaging. Future research should explore maintenance of effects and extent to which findings are repeatable in lower risk women. Given the high benefit to risk ratio, clinicians can inform young women at increased risk that exercise may blunt estrogen exposure while considering whether to try other preventive therapies.

Hamstring Muscle Use in Females During Hip-Extension and the Nordic Hamstring Exercise: An fMRI Study.

PubMed

Messer, Daniel J; Bourne, Matthew N; Williams, Morgan D; Al Najjar, Aiman; Shield, Anthony J

2018-04-23

Study Design Cross-sectional study. Background Understanding hamstring muscle activation patterns in resistance training exercises may have implications for the design of strength training and injury prevention programs. Unfortunately, surface electromyography studies have reported conflicting results with regard to hamstring muscle activation patterns in women. Objectives To determine the spatial patterns of hamstring muscle activity during the 45º hip-extension and Nordic hamstring exercises, in females using functional magnetic resonance imaging. Methods Six recreationally active females with no history of lower limb injury underwent functional magnetic resonance imaging (fMRI) on both thighs before and immediately after 5 sets of 6 bilateral eccentric contractions of the 45º hip-extension or Nordic exercises. Using fMRI, the transverse (T2) relaxation times were measured from pre- and post- exercise scans and the percentage increase in T2 was used as an index of muscle activation. Results fMRI revealed a significantly higher biceps femoris long head (BF LongHead ) to semitendinosus ratio during the 45° hip-extension than the Nordic exercise (P = .028). The T2 increase after 45° hip-extension was greater for BF LongHead (P < .001), semitendinosus and semimembranosus (P = .001) than that of biceps femoris short head (BF ShortHead ). During the Nordic exercise, the T2 increase for semitendinosus was greater than that of BF ShortHead (P < .001) and BF LongHead (P = .001). Conclusion While both exercises involve high levels of semitendinosus activation in women, the Nordic exercise preferentially recruits that muscle while the hip extension more evenly activates all of the biarticular hamstrings. J Orthop Sports Phys Ther, Epub 23 Apr 2018. doi:10.2519/jospt.2018.7748.

Cytokine Response to Diet and Exercise Affects Atheromatous Matrix Metalloproteinase-2/9 Activity in Mice.

PubMed

Shon, Soo-Min; Jang, Hee Jeong; Schellingerhout, Dawid; Kim, Jeong-Yeon; Ryu, Wi-Sun; Lee, Su-Kyoung; Kim, Jiwon; Park, Jin-Yong; Oh, Ji Hye; Kang, Jeong Wook; Je, Kang-Hoon; Park, Jung E; Kim, Kwangmeyung; Kwon, Ick Chan; Lee, Juneyoung; Nahrendorf, Matthias; Park, Jong-Ho; Kim, Dong-Eog

2017-09-25

The aim of this study is to identify the principal circulating factors that modulate atheromatous matrix metalloproteinase (MMP) activity in response to diet and exercise.Methods and Results:Apolipoprotein-E knock-out (ApoE -/- ) mice (n=56) with pre-existing plaque, fed either a Western diet (WD) or normal diet (ND), underwent either 10 weeks of treadmill exercise or had no treatment. Atheromatous MMP activity was visualized using molecular imaging with a MMP-2/9 activatable near-infrared fluorescent (NIRF) probe. Exercise did not significantly reduce body weight, visceral fat, and plaque size in either WD-fed animals or ND-fed animals. However, atheromatous MMP-activity was different; ND animals that did or did not exercise had similarly low MMP activities, WD animals that did not exercise had high MMP activity, and WD animals that did exercise had reduced levels of MMP activity, close to the levels of ND animals. Factor analysis and path analysis showed that soluble vascular cell adhesion molecule (sVCAM)-1 was directly positively correlated to atheromatous MMP activity. Adiponectin was indirectly negatively related to atheromatous MMP activity by way of sVCAM-1. Resistin was indirectly positively related to atheromatous MMP activity by way of sVCAM-1. Visceral fat amount was indirectly positively associated with atheromatous MMP activity, by way of adiponectin reduction and resistin elevation. MMP-2/9 imaging of additional mice (n=18) supported the diet/exercise-related anti-atherosclerotic roles for sVCAM-1. Diet and exercise affect atheromatous MMP activity by modulating the systemic inflammatory milieu, with sVCAM-1, resistin, and adiponectin closely interacting with each other and with visceral fat.

Scientific/Technical Report Bioenergetics Research Initiative Award number-DE-FG02-05ER64092

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trappe, Scott A

2009-12-04

General Project Overview and Final Technical Report This equipment grant was utilized to enhance the infrastructure of the Human Performance Laboratory at Ball State University. The laboratories primary focus is human based exercise physiology conducting research in the areas of sports performance, aging and exercise, unloading (space flight and bed rest), pediatric exercise and clinical exercise physiology. The main equipment supported by this grant was an ultrasound unit for cardiac and skeletal muscle imaging at the whole organ level, microscope system for micro imaging of skeletal muscle tissue, running treadmill for energy expenditure assessment, autoclave for sterilization, and upgrade tomore » our dual x–ray absorptiometry (DEXA) system that was utilized for body composition measurements. The equipment was involved in several human metabolic and skeletal muscle research projects as highlighted above. In particular, this equipment served a support role for other large–scale clinical projects funded by the National Institutes of Health (NIH), National Aeronautics and Space Administration (NASA), and corporate sponsors.« less

Strong is the new skinny: A content analysis of fitspiration websites.

PubMed

Boepple, Leah; Ata, Rheanna N; Rum, Ruba; Thompson, J Kevin

2016-06-01

"Fitspiration" websites are media that aim to inspire people to live healthy and fit lifestyles through motivating images and text related to exercise and diet. Given the link between similar Internet content (i.e., healthy living blogs) and problematic messages, we hypothesized that content on these sites would over-emphasize appearance and promote problematic messages regarding exercise and diet. Keywords "fitspo" and "fitspiration" were entered into search engines. The first 10 images and text from 51 individual websites were rated on a variety of characteristics. Results indicated that a majority of messages found on fitspiration websites focused on appearance. Other common themes included content promoting exercise for appearance-motivated reasons and content promoting dietary restraint. "Fitspiration" websites are a source of messages that reinforce over-valuation of physical appearance, eating concerns, and excessive exercise. Further research is needed to examine the impact viewing such content has on participants' psychological health. Copyright © 2016 Elsevier Ltd. All rights reserved.

Neurotoxicoses of small animals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simpson, S.T.

1976-02-01

Among the great variety of potentially neurotoxic substances are insecticides, rodenticides, herbicides, fungicides, heavy metals, plants, drugs, reptile and insect venoms, industrial chemicals and contaminated foodstuffs. The neurotoxicoses associated with several of these are described. Of the insecticides, organophosphates and chlorinated hydrocarbons are discussed. The heavy metals thallium and lead are discussed along with botulism and polyradiculoneuritis. 22 references.

40 CFR 261.3 - Definition of hazardous waste.

Code of Federal Regulations, 2010 CFR

2010-07-01

... residues, such as slag, resulting from high temperature metals recovery (HTMR) processing of K061, K062 or..., slag reactors, rotary hearth furnace/electric furnace combinations or industrial furnaces (as defined....009 Nickel 1.0 Selenium 0.16 Silver 0.30 Thallium 0.020 Zinc 70 Generic exclusion levels for F006...

40 CFR 261.3 - Definition of hazardous waste.

Code of Federal Regulations, 2011 CFR

2011-07-01

... residues, such as slag, resulting from high temperature metals recovery (HTMR) processing of K061, K062 or..., slag reactors, rotary hearth furnace/electric furnace combinations or industrial furnaces (as defined....009 Nickel 1.0 Selenium 0.16 Silver 0.30 Thallium 0.020 Zinc 70 Generic exclusion levels for F006...

Chemistry and superconductivity in thallium-based cuprates. Technical report No. 56, 1 June 1989-30 May 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenblatt, M.; Li, S.; McMills, L.E.

1990-06-01

Following the discoveries of high temperature superconductivity in the rare-earth copper oxide systems at 40K bY Bednorz and Muller in 1986 and at 90K by other researchers in 1987, Sheng and Hermann, in 1988, discovered superconductivity in the thallium-alkaline-earth copper oxide systems with critical temperatures as high as 120K. All of the Tl-based compounds can be described by the general formula, TlmA2Can-1CuO2n+m+2, where m=1 or 2; n=5; A=Ba, Sr. For convenience, the names of these compounds are abbreviated as 2223 for TlBa2Ca2Cu3O10, where each number denotes the number of Tl, Ba(Sr), Ca and Cu ions per formula, respectively. The compoundsmore » with m=1 and m=2 are usually referred to as single and double T1-O layered compounds, respectively. The highest superconducting transition temperature known so far was found in Tl2BaCa2Cu3O10 at 125K.« less

Advanced crystal growth techniques for thallium bromide semiconductor radiation detectors

NASA Astrophysics Data System (ADS)

Datta, Amlan; Becla, Piotr; Guguschev, Christo; Motakef, Shariar

2018-02-01

Thallium Bromide (TlBr) is a promising room-temperature radiation detector candidate with excellent charge transport properties. Currently, Travelling Molten Zone (TMZ) technique is widely used for growth of semiconductor-grade TlBr crystals. However, there are several challenges associated with this type of crystal growth process including lower yield, high thermal stress, and low crystal uniformity. To overcome these shortcomings of the current technique, several different crystal growth techniques have been implemented in this study. These include: Vertical Bridgman (VB), Physical Vapor Transport (PVT), Edge-defined Film-fed Growth (EFG), and Czochralski Growth (Cz). Techniques based on melt pulling (EFG and Cz) were demonstrated for the first time for semiconductor grade TlBr material. The viability of each process along with the associated challenges for TlBr growth has been discussed. The purity of the TlBr crystals along with its crystalline and electronic properties were analyzed and correlated with the growth techniques. Uncorrected 662 keV energy resolutions around 2% were obtained from 5 mm x 5 mm x 10 mm TlBr devices with virtual Frisch-grid configuration.

Characterization of Thallium Bromide Detectors Made From Material Purified by the Filter Method

NASA Astrophysics Data System (ADS)

Onodera, Toshiyuki; Hitomi, Keitaro; Tada, Tsutomu; Shoji, Tadayoshi; Mochizuki, Katsumi

2013-10-01

Thallium bromide (TlBr) has been regarded as candidate detector materials for the gamma-ray spectrometers operating at room temperature. In this study, a simple and rapid method, the filter method, was performed to purify a raw TlBr material used for fabrication of TlBr detectors. The material was loaded on shards of crashed quartz and installed in a Pyrex tube, and was melted using a furnace. A purified material passing through interspaces of the shards of quartz was collected in a quartz ampoule located at the outlet of the Pyrex tube. After the purification, impurities colored black extracted from the raw material remained. TlBr crystals were then grown by the travelling molten zone method both from the raw material and the purified material. TlBr detectors were fabricated from the grown crystals, and were characterized by measuring mobility-lifetime products (μτ) for carriers and gamma-ray spectra ( 137Cs) at room temperature. μτ for electrons of a TlBr detector fabricated from the purified material was around 5 times higher than that of a detector fabricated from the raw material.

The Effect of Experimental Geometry and Initial Conditions on the Shape of Coherent Population Trapping Resonances on the Fine Structure Levels of Thallium Atoms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karagodova, T.Ya.

2005-06-15

Specific features of the coherent population trapping effect are considered in the generalized {lambda} system whose lower levels are the magnetic sublevels of the fine structure levels of the thallium atom. Numerical experiments were performed aimed at examination of the coherent population trapping for the case of nontrivial, but feasible, initial populations of the upper metastable fine structure level. Such populations may be obtained, for example, due to the photodissociation of TlBr molecules. The possibility of reducing the number of resonances of the coherent population trapping in a multilevel system, which may be useful for high-resolution spectroscopy, is demonstrated. Itmore » is shown that the magnitude and shape of the resonances can be controlled by varying the orientation of the polarization vectors of the light field components with respect to each other and to a magnetic field. In addition, studying the shape of the coherent population trapping resonances for the atoms obtained by photodissociation of molecules may provide information about these molecules.« less

Advances in crystal growth, device fabrication and characterization of thallium bromide detectors for room temperature applications

NASA Astrophysics Data System (ADS)

Datta, Amlan; Moed, Demi; Becla, Piotr; Overholt, Matthew; Motakef, Shariar

2016-10-01

Thallium bromide (TlBr) is a promising room-temperature radiation detector candidate with excellent charge transport properties. However, several critical issues need to be addressed before deployment of this material for long-term field applications can be realized. In this paper, progress made towards solving some of these challenges is discussed. The most significant factors for achieving long-term performance stability for TlBr devices include residual stress as generated during crystal growth and fabrication processes, surface conditions, and the choice of contact metal. Modifications to the commonly used traveling molten zone growth technique for TlBr crystals can significantly minimize the stresses generated by large temperature gradients near the melt-solid interface of the growing crystal. Plasma processing techniques were introduced for the first time to modify the Br-etched TlBr surfaces, which resulted in improvements to the surface conditions, and consequently the spectroscopic response of the detectors. Palladium electrodes resulted a 20-fold improvement in the room-temperature device lifetime when compared to its Br-etched Pt counterpart.

Thallium halide radiation detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ijaz-ur-Rahman; Hofstadter, R.

1984-03-15

During a series of experiments on crystal conduction counters performed at Stanford University on thallium halide crystals, we have observed motion of both hole and electron carriers in a TlBr crystal. At a temperature near -90 /sup 0/C the hole motion produces larger pulses than electron motion. We have studied the behavior of TlBr, TlCl, and KRS-5 (40 mol % TlBr + 60 mol % TlI) crystals and examined them as possible crystal conduction detectors of ..cap alpha.. particles and ..gamma.. rays. TlBr appears to be a promising candidate for applications to nuclear physics and high-energy ..gamma..-ray physics. Modules ofmore » TlBr in ''crystal-ball'' geometry may lead to new detection possibilities. At -20 /sup 0/C space-charge accumulation in TlBr decreases to such an extent that operation at this temperature seems possible with moderate electrical gradients. In the long-neglected field of crystal conduction counters, we have potentially removed the space-charge limitation in TlBr and, allowing for both hole and electron motion, raised the possibility for spectroscopic performance of this material for ..gamma..-ray studies.« less

Performance limiting processes in room temperature thallium bromide radiation detectors

NASA Astrophysics Data System (ADS)

Datta, Amlan; Becla, Piotr; Moed, Demi; Motakef, Shariar

2015-09-01

Thallium Bromide (TlBr) is a promising room-temperature radiation detector candidate with excellent charge transport properties. However, several critical issues are needed to be addressed before deployment of this material for long-term field applications. In this paper, the relevance and, scientific and technological progress made towards solving these challenges for TlBr have been discussed. The possible research pathways to mitigate the concerns related to this material have been analyzed and clearly established. Findings from novel experiments performed at CapeSym have revealed that the most significant factors for achieving long-term performance stability for TlBr devices involve physical and chemical conditions of the surface, residual stress, and choice of metal contacts. Palladium electrodes on TlBr devices resulted in a 20-fold improvement in the device lifetime when compared to its Br-etched Pt counterpart. Electron and hole contributions towards the spectroscopic response of the TlBr detector significantly depend on the interaction position of the incoming radiation and was clearly observed in this study. TlBr device fabrication techniques need significant improvement in order to attain reliable, repeatable, and stable, long-term performance.

Analysis of neutron and gamma-ray streaming along the maze of NRCAM thallium production target room.

PubMed

Raisali, G; Hajiloo, N; Hamidi, S; Aslani, G

2006-08-01

Study of the shield performance of a thallium-203 production target room has been investigated in this work. Neutron and gamma-ray equivalent dose rates at various points of the maze are calculated by simulating the transport of streaming neutrons, and photons using Monte Carlo method. For determination of neutron and gamma-ray source intensities and their energy spectrum, we have applied SRIM 2003 and ALICE91 computer codes to Tl target and its Cu substrate for a 145 microA of 28.5 MeV protons beam. The MCNP/4C code has been applied with neutron source term in mode n p to consider both prompt neutrons and secondary gamma-rays. Then the code is applied for the prompt gamma-rays as the source term. The neutron-flux energy spectrum and equivalent dose rates for neutron and gamma-rays in various positions in the maze have been calculated. It has been found that the deviation between calculated and measured dose values along the maze is less than 20%.

Thallium as a tracer for preindustrial volcanic eruptions in an ice core record from Illimani, Bolivia.

PubMed

Kellerhals, Thomas; Tobler, Leonhard; Brütsch, Sabina; Sigl, Michael; Wacker, Lukas; Gäggeler, Heinz W; Schwikowski, Margit

2010-02-01

Trace element records from glacier and ice sheet archives provide insights into biogeochemical cycles, atmospheric circulation changes, and anthropogenic pollution history. We present the first continuous high-resolution thallium (Tl) record, derived from an accurately dated ice core from tropical South America, and discuss Tl as a tracer for volcanic eruptions. We identify four prominent Tl peaks and propose that they represent signals from the massive explosive eruptions of the "unknown 1258" A.D. volcano, of Kuwae ( approximately 1450 A.D.), Tambora (1815 A.D.), and Krakatoa (1883 A.D.). The highly resolved record was obtained with an improved setup for the continuous analysis of trace elements in ice with inductively coupled plasma sector field mass spectrometry (ICP-SFMS). The new setup allowed for a stronger initial acidification of the meltwater and shorter tubing length, thereby reducing the risk of memory effects and losses of analytes to the capillary walls. With a comparison of the continuous method to the established conventional decontamination and analysis procedure for discrete samples, we demonstrate the accuracy of the continuous method for Tl analyses.

The relationship between body esteem, exercise motivations, depression, and social support among female free clinic patients.

PubMed

Kamimura, Akiko; Christensen, Nancy; Al-Obaydi, Sarah; Solis, Silvia Patricia; Ashby, Jeanie; Greenwood, Jessica L J; Reel, Justine J

2014-01-01

Obesity is a significant public health problem in women's health. This study examined relationship between body esteem, exercise motivations, depression, and social support among female free clinic patients. Low-income women who are at risk for obesity and other health concerns would benefit from health education efforts. We compared 299 female and 164 male free clinic patients 18 years or older using assessments for body esteem, motivation to exercise, depression, and social support. Although female participants reported lower levels of body esteem and higher levels of depression compared with male participants (p < .01), female participants were more motivated to exercise for weight-related reasons than male participants (p < .05). U.S.-born female participants reported lower exercise motivations compared with non-U.S.-born female participants (p < .01). Social support might be an important factor to increase exercise motivation among female free clinic patients (p < .05); depression lowers levels of body esteem (p < .01). The results of this study suggest that female free clinic patients should receive gender-specific interventions to promote positive body image and physical activity. It is important for health educators to engage a myriad of physical activity motives to increase the likelihood that clients will experience enjoyment and sustained adoption of exercise into their lifestyle. Future practice and research should warrant the implementation of body image and physical activity programs and the potential impact of using exercise to reducing depression among female patients at free clinics. Copyright © 2014 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Empower U: effectiveness of an adolescent outreach and prevention program with sixth-grade boys and girls: a pilot study.

PubMed

Dowdy, Sharon; Alvarado, Maria; Atieno, Olive; Barker, Susan; Barrett, Sandra; Carlton, Anna; Cheshire, Ginny; Cooper, Melissa; Eastridge, Crystal; Grant, Shaylon; McHenry, Stefanie; Methvin, Kendra; Murray, Sherry; Ratcliff, Amy; Reynolds, Catherine; Scott, Abigail; Tidwell, Sherry; Turley, Jessica; Williamson, Lance

2013-01-01

Sixth graders are at a prime age to modify behaviors and beliefs regarding exercise, nutrition, body image, and smoking. Empower U was created to change knowledge, beliefs, and behaviors regarding these topics. This pilot study utilized pre/post assessments of 58 sixth graders from a private middle school in the midsouth. Results showed a significant increase in self-esteem as well as in exercise and nutrition knowledge and beliefs at posttest and a significant increase in body image as well as in self-reported exercise and nutrition behaviors at the 1-month follow-up. Empower U provides nurses with an effective educational program that may be useful in positively impacting health behaviors. Copyright © 2013 Elsevier Inc. All rights reserved.

Design and testing of an MRI-compatible cycle ergometer for non-invasive cardiac assessments during exercise

PubMed Central

2012-01-01

Background Magnetic resonance imaging (MRI) is an important tool for cardiac research, and it is frequently used for resting cardiac assessments. However, research into non-pharmacological stress cardiac evaluation is limited. Methods We aimed to design a portable and relatively inexpensive MRI cycle ergometer capable of continuously measuring pedalling workload while patients exercise to maintain target heart rates. Results We constructed and tested an MRI-compatible cycle ergometer for a 1.5 T MRI scanner. Resting and sub-maximal exercise images (at 110 beats per minute) were successfully obtained in 8 healthy adults. Conclusions The MRI-compatible cycle ergometer constructed by our research group enabled cardiac assessments at fixed heart rates, while continuously recording power output by directly measuring pedal force and crank rotation. PMID:22423637

HIGHER MODIFIED BECK DEPRESSION INVENTORY SCORES ARE ASSOCIATED WITH BODY, EATING, AND EXERCISE COMPARISONS BUT DECREASED EXERCISE AMOUNTS.

PubMed

Knepp, Michael M; Yoza, Jeffrey J; Quandt, Emily A

2015-06-01

Previous research has indicated that exercise can lead to decreased depression symptoms. The relationship of depression with right frontal lobe activity and self-image (body, eating, and exercise) were investigated as reasons why depressive symptoms might lead to decreased exercise. 120 college students (79 women) completed design fluency tasks followed by a set of questionnaires on depression and exercise. High (M = 23.03, SD = 5.92) and low quartiles (M = 3.11, SD = 1.59) were created using the Modified Beck Depression Inventory (mBDI) for primary analyses. The group with higher mBDI scores produced fewer unique designs (suggesting lower right frontal activity) and was more likely to make comparisons based on body shape, eating, and exercise. The group with higher mBDI scores reported significantly less strenuous and moderate exercise. These findings indicate that the relationship between exercise and depression could work in both directions. While exercise can be used as a potential treatment to decrease depression, increased depressive symptoms could be a hindrance to exercise.

Iterated Function Systems in the Classroom

ERIC Educational Resources Information Center

Waiveris, Charles

2007-01-01

The title may appear daunting, but the exercises, which can be presented to students from middle school to graduate school, are not. The exercises center on creating fractal images in the xy-plane with free. easy-to-use software and questions appropriate to the level of the student.

Potential environmental and human health impacts of rechargeable lithium batteries in electronic waste.

PubMed

Kang, Daniel Hsing Po; Chen, Mengjun; Ogunseitan, Oladele A

2013-05-21

Rechargeable lithium-ion (Li-ion) and lithium-polymer (Li-poly) batteries have recently become dominant in consumer electronic products because of advantages associated with energy density and product longevity. However, the small size of these batteries, the high rate of disposal of consumer products in which they are used, and the lack of uniform regulatory policy on their disposal means that lithium batteries may contribute substantially to environmental pollution and adverse human health impacts due to potentially toxic materials. In this research, we used standardized leaching tests, life-cycle impact assessment (LCIA), and hazard assessment models to evaluate hazardous waste classification, resource depletion potential, and toxicity potentials of lithium batteries used in cellphones. Our results demonstrate that according to U.S. federal regulations, defunct Li-ion batteries are classified hazardous due to their lead (Pb) content (average 6.29 mg/L; σ = 11.1; limit 5). However, according to California regulations, all lithium batteries tested are classified hazardous due to excessive levels of cobalt (average 163,544 mg/kg; σ = 62,897; limit 8000), copper (average 98,694 mg/kg; σ = 28,734; limit 2500), and nickel (average 9525 mg/kg; σ = 11,438; limit 2000). In some of the Li-ion batteries, the leached concentrations of chromium, lead, and thallium exceeded the California regulation limits. The environmental impact associated with resource depletion and human toxicity is mainly associated with cobalt, copper, nickel, thallium, and silver, whereas the ecotoxicity potential is primarily associated with cobalt, copper, nickel, thallium, and silver. However, the relative contribution of aluminum and lithium to human toxicity and ecotoxicity could not be estimated due to insufficient toxicity data in the models. These findings support the need for stronger government policy at the local, national, and international levels to encourage recovery, recycling, and reuse of lithium battery materials.

A novel crystallization method for visualizing the membrane localization of potassium channels.

PubMed Central

Lopatin, A N; Makhina, E N; Nichols, C G

1998-01-01

The high permeability of K+ channels to monovalent thallium (Tl+) ions and the low solubility of thallium bromide salt were used to develop a simple yet very sensitive approach to the study of membrane localization of potassium channels. K+ channels (Kir1.1, Kir2.1, Kir2.3, Kv2.1), were expressed in Xenopus oocytes and loaded with Br ions by microinjection. Oocytes were then exposed to extracellular thallium. Under conditions favoring influx of Tl+ ions (negative membrane potential under voltage clamp, or high concentration of extracellular Tl+), crystals of TlBr, visible under low-power microscopy, formed under the membrane in places of high density of K+ channels. Crystals were not formed in uninjected oocytes, but were formed in oocytes expressing as little as 5 microS K+ conductance. The number of observed crystals was much lower than the estimated number of functional channels. Based on the pattern of crystal formation, K+ channels appear to be expressed mostly around the point of cRNA injection when injected either into the animal or vegetal hemisphere. In addition to this pseudopolarized distribution of K+ channels due to localized microinjection of cRNA, a naturally polarized (animal/vegetal side) distribution of K+ channels was also frequently observed when K+ channel cRNA was injected at the equator. A second novel "agarose-hemiclamp" technique was developed to permit direct measurements of K+ currents from different hemispheres of oocytes under two-microelectrode voltage clamp. This technique, together with direct patch-clamping of patches of membrane in regions of high crystal density, confirmed that the localization of TlBr crystals corresponded to the localization of functional K+ channels and suggested a clustered organization of functional channels. With appropriate permeant ion/counterion pairs, this approach may be applicable to the visualization of the membrane distribution of any functional ion channel. PMID:9591643

A novel crystallization method for visualizing the membrane localization of potassium channels.

PubMed

Lopatin, A N; Makhina, E N; Nichols, C G

1998-05-01

The high permeability of K+ channels to monovalent thallium (Tl+) ions and the low solubility of thallium bromide salt were used to develop a simple yet very sensitive approach to the study of membrane localization of potassium channels. K+ channels (Kir1.1, Kir2.1, Kir2.3, Kv2.1), were expressed in Xenopus oocytes and loaded with Br ions by microinjection. Oocytes were then exposed to extracellular thallium. Under conditions favoring influx of Tl+ ions (negative membrane potential under voltage clamp, or high concentration of extracellular Tl+), crystals of TlBr, visible under low-power microscopy, formed under the membrane in places of high density of K+ channels. Crystals were not formed in uninjected oocytes, but were formed in oocytes expressing as little as 5 microS K+ conductance. The number of observed crystals was much lower than the estimated number of functional channels. Based on the pattern of crystal formation, K+ channels appear to be expressed mostly around the point of cRNA injection when injected either into the animal or vegetal hemisphere. In addition to this pseudopolarized distribution of K+ channels due to localized microinjection of cRNA, a naturally polarized (animal/vegetal side) distribution of K+ channels was also frequently observed when K+ channel cRNA was injected at the equator. A second novel "agarose-hemiclamp" technique was developed to permit direct measurements of K+ currents from different hemispheres of oocytes under two-microelectrode voltage clamp. This technique, together with direct patch-clamping of patches of membrane in regions of high crystal density, confirmed that the localization of TlBr crystals corresponded to the localization of functional K+ channels and suggested a clustered organization of functional channels. With appropriate permeant ion/counterion pairs, this approach may be applicable to the visualization of the membrane distribution of any functional ion channel.

Chemical spray pyrolysis of Tl-Ba-Ca-Cu-O high-T(sub c) superconductors for high-field bitter magnets

NASA Technical Reports Server (NTRS)

Derochemont, L. Pierre; Zhang, John G.; Squillante, Michael R.; Hermann, A. M.; Duan, H. M.; Andrews, Robert J.; Kelliher, Warren C.

1991-01-01

The deposition of Tl-Ba-Ca-Cu-O thick films by spray pyrolyzing a Ba-Ca-Cu-O precursor film and diffusing thallium into the film to form the superconducting phase is examined. This approach was taken to reduce exposure to thallium and its health and safety hazards. The Tl-Ba-Ca-Cu-O system was selected because it has very attractive features which make it appealing to device and manufacturing engineering. Tl-Ba-Ca-Cu-O will accommodate a number of superconducting phases. This attribute makes it very forgiving to stoichiometric fluctuations in the bulk and film. It has excellent thermal and chemical stability, and appears to be relatively insensitive to chemical impurities. Oxygen is tightly bound into the systems, consequently there is no orthorhombic (conductor) to tetragonal (insulator) transition which would affect a component's lifetime. More significantly, the thallium based superconductors appear to have harder magnetic properties than the other high-Tc oxide ceramics. Estimates using magnetoresistance measurements indicate that at 77 K Tl2Ba2CaCu2O10 will have an upper critical field, H(sub c2) fo 26 Tesla for applied fields parallel to the c-axis and approximately 1000 Tesla for fields oriented in the a-b plane. Results to date have shown that superconducting films can be reproducibly deposited on 100 oriented MgO substrates. One film had a zero resistance temperature of 111.5 K. Furthermore, x ray diffraction analysis of the films showed preferential c-axis orientation parallel to the plane of the substrate. These results have now made it possible to consider the manufacture of a superconducting tape wire which can be configured into a topology useful for high-field magnet designs. The research which leads to the preparation of these films and plans for further development are reviewed.

Potential Environmental and Human Health Impacts of Rechargeable Lithium Batteries in Electronic Waste

PubMed Central

Kang, Daniel Hsing Po; Chen, Mengjun; Ogunseitan, Oladele A.

2013-01-01

Rechargeable lithium-ion (Li-ion) and lithium-polymer (Li-poly) batteries have recently become dominant in consumer electronic products because of advantages associated with energy density and product longevity. However, the small size of these batteries, the high rate of disposal of consumer products in which they are used, and the lack of uniform regulatory policy on their disposal means that lithium batteries may contribute substantially to environmental pollution and adverse human health impacts due to potentially toxic materials. In this research, we used standardized leaching tests, life-cycle impact assessment (LCIA), and hazard assessment models to evaluate hazardous waste classification, resource depletion potential, and toxicity potentials of lithium batteries used in cellphones. Our results demonstrate that according to U.S. federal regulations, defunct Li-ion batteries are classified hazardous due to their lead (Pb) content (average 6.29 mg/L; σ = 11.1; limit 5). However, according to California regulations, all lithium batteries tested are classified hazardous due to excessive levels of cobalt (average 163 544 mg/kg; σ = 62 897; limit 8000), copper (average 98 694 mg/kg; σ = 28 734; limit 2500), and nickel (average 9525 mg/kg; σ = 11 438; limit 2000). In some of the Li-ion batteries, the leached concentrations of chromium, lead, and thallium exceeded the California regulation limits. The environmental impact associated with resource depletion and human toxicity is mainly associated with cobalt, copper, nickel, thallium, and silver, whereas the ecotoxicity potential is primarily associated with cobalt, copper, nickel, thallium, and silver. However, the relative contribution of aluminum and lithium to human toxicity and ecotoxicity could not be estimated due to insufficient toxicity data in the models. These findings support the need for stronger government policy at the local, national, and international levels to encourage recovery, recycling, and reuse of lithium battery materials. PMID:23638841

Thallium isotope composition of the upper continental crust and rivers - An investigation of the continental sources of dissolved marine thallium

USGS Publications Warehouse

Nielsen, S.G.; Rehkamper, M.; Porcelli, D.; Andersson, P.; Halliday, A.N.; Swarzenski, P.W.; Latkoczy, C.; Gunther, D.

2005-01-01

The thallium (Tl) concentrations and isotope compositions of various river and estuarine waters, suspended riverine particulates and loess have been determined. These data are used to evaluate whether weathering reactions are associated with significant Tl isotope fractionation and to estimate the average Tl isotope composition of the upper continental crust as well as the mean Tl concentration and isotope composition of river water. Such parameters provide key constraints on the dissolved Tl fluxes to the oceans from rivers and mineral aerosols. The Tl isotope data for loess and suspended riverine detritus are relatively uniform with a mean of ??205Tl = -2.0 ?? 0.3 (??205Tl represents the deviation of the 205Tl/203Tl isotope ratio of a sample from NIST SRM 997 Tl in parts per 104). For waters from four major and eight smaller rivers, the majority were found to have Tl concentrations between 1 and 7 ng/kg. Most have Tl isotope compositions very similar (within ??1.5 ??205Tl) to that deduced for the upper continental crust, which indicates that no significant Tl isotope fractionation occurs during weathering. Based on these results, it is estimated that rivers have a mean natural Tl concentration and isotope composition of 6 ?? 4 ng/kg and ??205Tl = -2.5 ?? 1.0, respectively. In the Amazon estuary, both additions and losses of Tl were observed, and these correlate with variations in Fe and Mn contents. The changes in Tl concentrations have much lower amplitudes, however, and are not associated with significant Tl isotope effects. In the Kalix estuary, the Tl concentrations and isotope compositions can be explained by two-component mixing between river water and a high-salinity end member that is enriched in Tl relative to seawater. These results indicate that Tl can display variable behavior in estuarine systems but large additions and losses of Tl were not observed in the present study. Copyright ?? 2005 Elsevier Ltd.

Anatomical and Functional Images of in vitro and in vivo Tissues by NIR Time-domain Diffuse Optical Tomography

NASA Astrophysics Data System (ADS)

Zhao, Huijuan; Gao, Feng; Tanikawa, Yukari; Homma, Kazuhiro; Onodera, Yoichi; Yamada, Yukio

Near infra-red (NIR) diffuse optical tomography (DOT) has gained much attention and it will be clinically applied to imaging breast, neonatal head, and the hemodynamics of the brain because of its noninvasiveness and deep penetration in biological tissue. Prior to achieving the imaging of infant brain using DOT, the developed methodologies need to be experimentally justified by imaging some real organs with simpler structures. Here we report our results of an in vitro chicken leg and an in vivo exercising human forearm from the data measured by a multi-channel time-resolved NIR system. Tomographic images were reconstructed by a two-dimensional image reconstruction algorithm based on a modified generalized pulse spectrum technique for simultaneous reconstruction of the µa and µs´. The absolute µa- and µs´-images revealed the inner structures of the chicken leg and the forearm, where the bones were clearly distinguished from the muscle. The Δµa-images showed the blood volume changes during the forearm exercise, proving that the system and the image reconstruction algorithm could potentially be used for imaging not only the anatomic structure but also the hemodynamics in neonatal heads.

Folds and Etudes

ERIC Educational Resources Information Center

Bean, Robert

2007-01-01

In this article, the author talks about "Folds" and "Etudes" which are images derived from anonymous typing exercises that he found in a used copy of "Touch Typing Made Simple". "Etudes" refers to the musical tradition of studies for a solo instrument, which is a typewriter. Typing exercises are repetitive attempts to type words and phrases…

Stimulated echo diffusion tensor imaging and SPAIR T2 -weighted imaging in chronic exertional compartment syndrome of the lower leg muscles.

PubMed

Sigmund, Eric E; Sui, Dabang; Ukpebor, Obehi; Baete, Steven; Fieremans, Els; Babb, James S; Mechlin, Michael; Liu, Kecheng; Kwon, Jane; McGorty, KellyAnne; Hodnett, Philip A; Bencardino, Jenny

2013-11-01

To evaluate the performance of diffusion tensor imaging (DTI) in the evaluation of chronic exertional compartment syndrome (CECS) as compared to T2 -weighted (T2w) imaging. Using an Institutional Review Board (IRB)-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant protocol, spectral adiabatic inversion recovery (SPAIR) T2w imaging and stimulated echo DTI were applied to eight healthy volunteers and 14 suspected CECS patients before and after exertion. Longitudinal and transverse diffusion eigenvalues, mean diffusivity (MD), and fractional anisotropy (FA) were measured in seven calf muscle compartments, which in patients were classified by their response on T2w: normal (<20% change), and CECS (>20% change). Mixed model analysis of variance compared subject groups and compartments in terms of response factors (post/pre-exercise ratios) of DTI parameters. All diffusivities significantly increased (P < 0.0001) and FA decreased (P = 0.0014) with exercise. Longitudinal diffusion responses were significantly smaller than transversal diffusion responses (P < 0.0001). Nineteen of 98 patient compartments were classified as CECS on T2w. MD increased by 3.8 ± 3.4% (volunteer), 7.4 ± 4.2% (normal), and 9.1 ± 7.0% (CECS) with exercise. DTI shows promise as an ancillary imaging method in the diagnosis and understanding of the pathophysiology in CECS. Future studies may explore its utility in predicting response to treatment. Copyright © 2013 Wiley Periodicals, Inc.

Detection and characterization of exercise induced muscle damage (EIMD) via thermography and image processing

NASA Astrophysics Data System (ADS)

Avdelidis, N. P.; Kappatos, V.; Georgoulas, G.; Karvelis, P.; Deli, C. K.; Theodorakeas, P.; Giakas, G.; Tsiokanos, A.; Koui, M.; Jamurtas, A. Z.

2017-04-01

Exercise induced muscle damage (EIMD), is usually experienced in i) humans who have been physically inactive for prolonged periods of time and then begin with sudden training trials and ii) athletes who train over their normal limits. EIMD is not so easy to be detected and quantified, by means of commonly measurement tools and methods. Thermography has been used successfully as a research detection tool in medicine for the last 6 decades but very limited work has been reported on EIMD area. The main purpose of this research is to assess and characterize EIMD, using thermography and image processing techniques. The first step towards that goal is to develop a reliable segmentation technique to isolate the region of interest (ROI). A semi-automatic image processing software was designed and regions of the left and right leg based on superpixels were segmented. The image is segmented into a number of regions and the user is able to intervene providing the regions which belong to each of the two legs. In order to validate the image processing software, an extensive experimental investigation was carried out, acquiring thermographic images of the rectus femoris muscle before, immediately post and 24, 48 and 72 hours after an acute bout of eccentric exercise (5 sets of 15 maximum repetitions), on males and females (20-30 year-old). Results indicate that the semi-automated approach provides an excellent bench-mark that can be used as a clinical reliable tool.

[Exercise stress test and dobutamine stress echocardiography for the prognostic stratification after uncomplicated acute myocardial infarction].

PubMed

Vitiello, Nicola; Cirillo, Raffaele; Granato, Luigi; Coppola, Vincenzo; di Palma, Francesco

2007-05-01

Exercise stress test and dobutamine stress echocardiography are usually performed early after an uncomplicated acute myocardial infarction in the prognostic stratification of patients to define the optimal diagnostic and therapeutic procedure. The aim of this study was to evaluate if the association of an imaging test could increase exercise test capability to identify patients with residual ischemia and patients at high risk of events in the follow-up. Four hundred and forty-two consecutive patients underwent exercise stress testing and dobutamine stress echocardiography before discharge and subsequently coronary angiography within 30 days. In case of submaximal negative result at the exercise test, this was repeated 20 days after discharge. The follow-up lasted 26.8 +/- 9 months. The endpoints were death, reinfarction, and unstable angina requiring hospitalization or revascularization intervention. Both tests and their association showed a higher sensitivity in males; in females dobutamine stress echocardiography had a higher specificity. In females, the addition of dobutamine stress echocardiography increased either the negative or the positive prognostic values of exercise stress test by 31% and 5.6%, respectively. In males, the negative prognostic value increased by 15.5%, whereas the positive prognostic value decreased by 12%. A low exercise capability (<6 METs) showed an event predictive value independent of test results and any other variables. The event-free survival curves correlated with exercise capability differed shortly after the first months both in males and females. These results suggest different stratification procedures with regard to gender: in males, the exercise stress test might be sufficient at discharge, to be repeated 20 days later, if submaximal negative. In females, it seems to be useful to associate an imaging test at discharge. In any case, the exercise stress test remains the main step in the stratification procedure also for its capability to identify patients who are at high risk of events in the follow-up.

SAPHIRE (scintillator avalanche photoconductor with high resolution emitter readout) for low dose x-ray imaging: Spatial resolution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Dan; Zhao Wei

2008-07-15

An indirect flat panel imager (FPI) with programmable avalanche gain and field emitter array (FEA) readout is being investigated for low-dose and high resolution x-ray imaging. It is made by optically coupling a structured x-ray scintillator, e.g., thallium (Tl) doped cesium iodide (CsI), to an amorphous selenium (a-Se) avalanche photoconductor called high-gain avalanche rushing amorphous photoconductor (HARP). The charge image created by the scintillator/HARP (SHARP) combination is read out by the electron beams emitted from the FEA. The proposed detector is called scintillator avalanche photoconductor with high resolution emitter readout (SAPHIRE). The programmable avalanche gain of HARP can improve themore » low dose performance of indirect FPI while the FEA can be made with pixel sizes down to 50 {mu}m. Because of the avalanche gain, a high resolution type of CsI (Tl), which has not been widely used in indirect FPI due to its lower light output, can be used to improve the high spatial frequency performance. The purpose of the present article is to investigate the factors affecting the spatial resolution of SAPHIRE. Since the resolution performance of the SHARP combination has been well studied, the focus of the present work is on the inherent resolution of the FEA readout method. The lateral spread of the electron beam emitted from a 50 {mu}mx50 {mu}m pixel FEA was investigated with two different electron-optical designs: mesh-electrode-only and electrostatic focusing. Our results showed that electrostatic focusing can limit the lateral spread of electron beams to within the pixel size of down to 50 {mu}m. Since electrostatic focusing is essentially independent of signal intensity, it will provide excellent spatial uniformity.« less

Targeted Imaging of the Spatial and Temporal Variation of Matrix Metalloproteinase Activity in Porcine Model of Post-Infarct Remodeling: Relationship to Myocardial Dysfunction

PubMed Central

Sahul, Zakir H.; Mukherjee, Rupak; Song, James; McAteer, Jarod; Stroud, Robert E.; Dione, Donald P.; Staib, Lawrence; Papademetris, Xenophon; Dobrucki, Lawrence W.; Duncan, James S.; Spinale, Francis G.; Sinusas, Albert J.

2011-01-01

Background Matrix metalloproteinases (MMPs) are known to modulate left ventricular (LV) remodeling after a myocardial infarction (MI). However, the temporal and spatial variation of MMP activation and their relationship to mechanical dysfunction post MI remains undefined. Methods and Results MI was surgically induced in pigs (n=23) and cine MR and dual isotope hybrid SPECT/CT imaging obtained using thallium-201 (201Tl) and a technetium-99m labeled MMP targeted tracer (99mTc-RP805) at 1, 2 and 4 weeks post MI along with controls (n=5). Regional myocardial strain was computed from MR images and related to MMP zymography and ex vivo myocardial 99mTc-RP805 retention. MMP activation as assessed by in vivo and ex vivo 99mTc-RP805 imaging/retention studies was increased nearly 5-fold within the infarct region at 1 week post-MI and remained elevated up to 1 month post-MI. The post-MI change in LV end-diastolic volumes was correlated with MMP activity (y=31.34e0.48x, p=0.04). MMP activity was increased within the border and remote regions early post-MI, but declined over 1 month. There was a high concordance between regional 99mTc-RP805 uptake and ex vivo MMP-2 activity. Conclusions A novel, multimodality non-invasive hybrid SPECT/CT imaging approach was validated and applied for in vivo evaluation of MMP activation in combination with cine MR analysis of LV deformation. Increased 99mTc-RP805 retention was seen throughout the heart early post-MI and was not purely a reciprocal of 201Tl perfusion. 99mTc-RP805 SPECT/CT imaging may provide unique information regarding regional myocardial MMP activation and predict late post-MI LV remodeling. PMID:21505092

The effect of core stability and general exercise on abdominal muscle thickness in non-specific chronic low back pain using ultrasound imaging.

PubMed

Shamsi, MohammadBagher; Sarrafzadeh, Javad; Jamshidi, Aliashraf; Zarabi, Vida; Pourahmadi, Mohammad Reza

2016-05-01

There is a controversy regarding whether core stability exercise (CSE) is more effective than general exercise (GE) for chronic LBP. To compare different exercises regarding their effect on improving back strength and stability, performance of abdominal muscles is a useful index. Ultrasound imaging for measuring muscle thickness could be used to assess muscle performance. The aim of this study was to compare CSE and GE in chronic LBP using ultrasound imaging for measurement of thickness of the deep stabilizing and main global trunk muscles in non-specific chronic LBP. Each program included 16 training sessions three times a week. Using ultrasound imaging, four transabdominal muscle thickness were measured before and after the intervention. Disability and pain were measured as secondary outcomes. After the intervention on participants (n = 43), a significant increase in muscle thickness (hypertrophy) was seen only in right and left rectus abdominis in the GE group, but significant difference to the CSE group was only on the right side. Disability and pain reduced within the groups without a significant difference in the change between them. The present results provided evidence that only GE increased right and left rectus muscle thickness. The only significant difference between CSE and GE groups was the right rectus thickness. As rectus is a global muscle, the effect of GE on strength improvement (one side stronger than the other) may have a negative effect on motor control of lumbopelvic muscles and possibly increase the risk of back pain occurring or becoming worse, though this was not observed in the present study.

Physical property measurements of doped cesium iodide crystals

NASA Technical Reports Server (NTRS)

Synder, R. S.; Clotfelter, W. N.

1974-01-01

Mechanical and thermal property values are reported for crystalline cesium iodide doped with sodium and thallium. Young's modulus, bulk modulus, shear modulus, and Poisson's ratio were obtained from ultrasonic measurements. Young's modulus and the samples' elastic and plastic behavior were also measured under tension and compression. Thermal expansion and thermal conductivity were the temperature dependent measurements that were made.

Alternating Wolff-Parkinson-White syndrome associated with attack of angina

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mangiafico, R.A.; Petralito, A.; Grimaldi, D.R.

1990-07-01

In a patient with Wolff-Parkinson-White syndrome and an inferior-posterior bypass tract, transient restoration of normal conduction occurred during an attack of angina. The ECG pattern of inferior posterior ischemia was present when the conduction was normal. Thallium scintigraphy showed a reversible posterolateral perfusion defect. The possible mechanisms for production of intermittent preexcitation are discussed.

Scintillator material

DOEpatents

Anderson, David F.; Kross, Brian J.

1994-01-01

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

Scintillator material

DOEpatents

Anderson, David F.; Kross, Brian J.

1992-01-01

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

Serum anti-Müllerian hormone and ovarian morphology assessed by magnetic resonance imaging in response to acupuncture and exercise in women with polycystic ovary syndrome: secondary analyses of a randomized controlled trial.

PubMed

Leonhardt, Henrik; Hellström, Mikael; Gull, Berit; Lind, Anna-Karin; Nilsson, Lars; Janson, Per Olof; Stener-Victorin, Elisabet

2015-03-01

To investigate whether electro-acupuncture or physical exercise influence serum anti-Müllerian hormone (AMH), antral follicle count (AFC) or ovarian volume in women with polycystic ovary syndrome (PCOS). Secondary analyses of a prospective, randomized controlled clinical trial. University Hospital, Sweden. Seventy-four women with PCOS recruited from the general population. Women with PCOS were randomized to 16 weeks of electro-acupuncture (14 treatments), exercise (at least three times/week), or no intervention. Serum AMH recorded at baseline, after 16 weeks of intervention, and at follow up at 32 weeks. AFC, and ovarian volume assessed by magnetic resonance imaging at baseline and at follow up at 32 weeks. After 16 weeks of intervention, serum levels of AMH were significantly decreased in the electro-acupuncture group by 17.5% (p < 0.001), and differed from the change in the exercise group. AMH remained decreased by 15% (p = 0.004) also at follow up at 32 weeks, but did not differ from the exercise or the no intervention groups. There was a decrease by 8.5% (p = 0.015) in ovarian volume between baseline and follow up in the electro-acupuncture group, and by 11.7% (p = 0.01) in AFC in the physical exercise group. No other variables were affected. This study is the first to demonstrate that acupuncture reduces serum AMH levels and ovarian volume. Physical exercise did not influence circulating AMH or ovarian volume. Despite a within-group decrease in AFC, exercise did not lead to a between-group difference. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

Impaired atrioventricular transport in patients with transposition of the great arteries palliated by atrial switch and preserved systolic right ventricular function: A magnetic resonance imaging study.

PubMed

Ladouceur, Magalie; Kachenoura, Nadjia; Soulat, Gilles; Bollache, Emilie; Redheuil, Alban; Azizi, Michel; Delclaux, Christophe; Chatellier, Gilles; Boutouyrie, Pierre; Iserin, Laurence; Bonnet, Damien; Mousseaux, Elie

2017-07-01

We aimed (1) determine if systemic right ventricle filling parameters influence systemic right ventricle stroke volume in adult patients with D-transposition of the great arteries (D-TGA) palliated by atrial switch, using cardiac magnetic resonance imaging and echocardiography, and (2) to study relationship of these diastolic parameters with exercise performance and BNP, in patients with preserved systolic systemic right ventricle function. Single-center, cross-sectional, prospective study. In patients with D-TGA palliated by atrial switch, diastolic dysfunction of the systemic right ventricle may precede systolic dysfunction. Forty-five patients with D-TGA and atrial switch and 45 age and sex-matched healthy subjects underwent cardiac magnetic resonance imaging and echocardiography. Filling flow-rates measured by phase-contrast cardiac magnetic resonance imaging were analyzed using customized software to estimate diastolic parameters and compared with exercise performance. In D-TGA, early filling of systemic right ventricle was impaired with a lower peak filling rate normalized by filling volume (Ef/FV measured by cardiac magnetic resonance imaging) and a higher early filling peak velocity normalized by early peak myocardial velocity (E US /Ea measured by echocardiography) compared with controls (P ≤ .04). Stroke volume of systemic right ventricle showed a direct and significant association with pulmonary venous pathway size (respectively r = 0.50, P < .01). Systemic right atrial area and systemic right ventricle mass/volume index measured by cardiac magnetic resonance imaging, as well as Ef/FV were significantly correlated with exercise performances and BNP (P < .01). All correlations were independent of age, gender, body mass index and blood pressure. Systemic right ventricle pre-load and stroke volume depend mainly on intraatrial pathway function. Moreover, systemic right ventricle remodeling and right atrial dysfunction impair systemic right ventricle filling, leading to BNP increase and exercise limitation. Cardiac magnetic resonance imaging should assess systemic right ventricle filling abnormalities in D-TGA patients. © 2017 Wiley Periodicals, Inc.

Promoting Active Learning by Practicing the "Self-Assembly" of Model Analytical Instruments

ERIC Educational Resources Information Center

Algar, W. Russ; Krull, Ulrich J.

2010-01-01

In our upper-year instrumental analytical chemistry course, we have developed "cut-and-paste" exercises where students "build" models of analytical instruments from individual schematic images of components. These exercises encourage active learning by students. Instead of trying to memorize diagrams, students are required to think deeply about…

Exercise 30 minutes a day (image)

MedlinePlus

You get the most benefit from exercise if you do it for at least 30 minutes a day for 5 to 6 days a week. But you do not have to do 30 minutes in a row. Studies suggest that you ... for 10 minutes 3 times a day as you do during a longer session.

The role of long-term physical exercise on performance and brain activation during the Stroop colour word task in fibromyalgia patients.

PubMed

Martinsen, S; Flodin, P; Berrebi, J; Löfgren, M; Bileviciute-Ljungar, I; Mannerkorpi, K; Ingvar, M; Fransson, P; Kosek, E

2018-05-01

The Stroop colour word test (SCWT) has been widely used to assess changes in cognitive performance such as processing speed, selective attention and the degree of automaticity. Moreover, the SCWT has proven to be a valuable tool to assess neuronal plasticity that is coupled to improvement in performance in clinical populations. In a previous study, we showed impaired cognitive processing during SCWT along with reduced task-related activations in patients with fibromyalgia. In this study, we used SCWT and functional magnetic resonance imagingFMRI to investigate the effects of a 15-week physical exercise intervention on cognitive performance, task-related cortical activation and distraction-induced analgesia (DIA) in patients with fibromyalgia and healthy controls. The exercise intervention yielded reduced fibromyalgia symptoms, improved cognitive processing and increased task-related activation of amygdala, but no effect on DIA. Our results suggest beneficial effects of physical exercise on cognitive functioning in FM. © 2017 The Authors. Clinical Physiology and Functional Imaging published by John Wiley & Sons Ltd on behalf of Scandinavian Society of Clinical Physiology and Nuclear Medicine.

Building the body: active learning laboratories that emphasize practical aspects of anatomy and integration with radiology.

PubMed

Zumwalt, Ann C; Lufler, Rebecca S; Monteiro, Joseph; Shaffer, Kitt

2010-01-01

Active learning exercises were developed to allow advanced medical students to revisit and review anatomy in a clinically meaningful context. In our curriculum, students learn anatomy two to three years before they participate in the radiology clerkship. These educational exercises are designed to review anatomy content while highlighting its relevance to the study of radiology. Laboratory exercises were developed using inexpensive materials in the form of hands-on stations designed for use by students working together in small groups. Station exercises include model building, exploring relevant radiological imaging, and practicing clinical techniques. Students are encouraged to move from abstract conceptualization of the anatomy using models to applying knowledge to living tissues by using a portable ultrasound to explore superficial anatomy on each other. Stations are designed to integrate knowledge and reemphasize concepts in different contexts, so that upon completion students have a reinforced understanding of the three-dimensional anatomy of the region in question, the appearance of the anatomy on radiological images, and an appreciation of the relevance of the anatomy to radiological procedures. (c) 2010 American Association of Anatomists.

Muscle dysmorphia: could it be classified as an addiction to body image?

PubMed

Foster, Andrew C; Shorter, Gillian W; Griffiths, Mark D

2015-03-01

Muscle dysmorphia (MD) describes a condition characterised by a misconstrued body image in which individuals who interpret their body size as both small or weak even though they may look normal or highly muscular.MD has been conceptualized as a type of body dysmorphic disorder, an eating disorder, and obsessive–compulsive disorder symptomatology. METHOD AND AIM: Through a review of the most salient literature on MD, this paper proposes an alternative classification of MD--the ‘Addiction to Body Image’ (ABI) model--using Griffiths (2005)addiction components model as the framework in which to define MD as an addiction. It is argued the addictive activity in MD is the maintaining of body image via a number of different activities such as bodybuilding, exercise,eating certain foods, taking specific drugs (e.g., anabolic steroids), shopping for certain foods, food supplements,and the use or purchase of physical exercise accessories). In the ABI model, the perception of the positive effects on the self-body image is accounted for as a critical aspect of the MD condition (rather than addiction to exercise or certain types of eating disorder). Based on empirical evidence to date, it is proposed that MD could be re-classified as an addiction due to the individual continuing to engage in maintenance behaviours that may cause long-term harm.

In vivo detection of exercised-induced ultrastructural changes in genetically-altered murine skeletal muscle using polarization-sensitive optical coherence tomography

NASA Astrophysics Data System (ADS)

Boppart, Stephen

2006-02-01

Skeletal muscle fibers are a known source of form birefringence in biological tissue. The birefringence present in skeletal muscle is associated with the ultrastructure of individual sarcomeres, specifically the arrangement of A-bands corresponding to the thick myosin filaments. Certain structural proteins that prevent damage and maintain the structural and functional health of the muscle fiber preserve the organization of the Abands in skeletal muscle. Therefore, the level of birefringence detected can estimate the health of the muscle as well as the damage incurred during exercise. Murine skeletal muscle from both genetically-altered (mdx) and normal (wild-type) specimens were imaged in vivo with a fiber-based PSOCT imaging system to quantitatively determine the level of birefringence present in the tissue before and after exercise. The mdx muscle lacks dystrophin, a structural protein that is mutated in Duchenne muscular dystrophy in humans. Muscle from these mdx mice exhibited a marked decrease in birefringence after exercise, whereas the wild-type muscle was highly birefringent before and after exercise. The quantitative results from this tissue optics study suggest for the first time that there is a distinct relationship between the degree of birefringence detected using PS-OCT and the sarcomeric ultrastructure present within skeletal muscle.

Comparing a Yoga Class with a Resistance Exercise Class: Effects on Body Satisfaction and Social Physique Anxiety in University Women.

PubMed

Gammage, Kimberley L; Drouin, Breanne; Lamarche, Larkin

2016-11-01

The current study compared a single yoga group exercise class and a resistance group exercise class for their effects on state body satisfaction and social physique anxiety in women. A pretest-posttest design was used. Participants (N = 46) completed both a resistance exercise class and yoga class in a counterbalanced order. Measures of body satisfaction and social physique anxiety were completed immediately before and after each class. A 2 (time) × 2 (class type) repeatedmeasures multiple analysis of variance showed a significant overall Time × Class Type interaction (F 2,44 = 5.69, P < .01, η p 2 = .21). There was a significant increase in body satisfaction after the yoga class. After both classes, there was a significant decrease in social physique anxiety, but the magnitude of the change was larger after the yoga class than after the resistance class. Both types of exercise class were associated with improvements in body image, but there were greater improvements after the yoga class. This study provided evidence of the positive effects of yoga for reducing state social physique anxiety and increasing state body satisfaction, adding to correlational evidence suggesting that yoga is particularly beneficial for improving body image-related outcomes in women.

Application of TlBr to nuclear medicine imaging

NASA Astrophysics Data System (ADS)

Cirignano, Leonard; Kim, Hadong; Kargar, Alireza; Churilov, Alexei V.; Ciampi, Guido; Higgins, William; Kim, Suyoung; Barber, Bradford; Haston, Kyle; Shah, Kanai

2012-10-01

Thallium bromide (TlBr) has been under development for room temperature gamma ray spectroscopy due to high density, high Z and wide bandgap of the material. Furthermore, its low melting point (460 °C), cubic crystal structure and congruent melting with no solid-solid phase transitions between the melting point and room temperature, TlBr can be grown by relatively simple melt based methods. As a result of improvements in material processing and detector fabrication over the last several years, TlBr with electron mobility-lifetime products (μeτe) in the mid 10-3 cm2/V range has been obtained. In this paper we are going to report on our unipolar charging TlBr results for the application as a small animal imaging. For SPECT application, about 5 mm thick pixellated detectors were fabricated and tested. About 1 % FWHM at 662 keV energy resolution was estimated at room temperature. By applying the depth correction technique, less than 1 % energy resolution was estimated. We are going to report the results from orthogonal strip TlBr detector for PET application. In this paper we also present our latest detector highlights and recent progress made in long term stability of TlBr detectors at or near room temperature. This work is being supported by the Domestic Nuclear Detection Office (DNDO) and the Department of Energy (DOE).

Myocardial perfusion imaging in patients with a recent, normal exercise test.

PubMed

Bovin, Ann; Klausen, Ib C; Petersen, Lars J

2013-03-26

To investigate the added value of myocardial perfusion scintigraphy imaging (MPI) in consecutive patients with suspected coronary artery disease (CAD) and a recent, normal exercise electrocardiography (ECG). This study was a retrospective analysis of consecutive patients referred for MPI during a 2-year period from 2006-2007 at one clinic. All eligible patients were suspected of suffering from CAD, and had performed a satisfactory bicycle exercise test (i.e., peak heart rate > 85% of the expected, age-predicted maximum) within 6 mo of referral, their exercise ECG was had no signs of ischemia, there was no exercise-limiting angina, and no cardiac events occurred between the exercise test and referral. The patients subsequently underwent a standard 2-d, stress-rest exercise MPI. Ischemia was defined based on visual scoring supported by quantitative segmental analysis (i.e., sum of stress score > 3). The results of cardiac catheterization were analyzed, and clinical follow up was performed by review of electronic medical files. A total of 56 patients fulfilled the eligibility criteria. Most patients had a low or intermediate ATPIII pre-test risk of CAD (6 patients had a high pre-test risk). The referral exercise test showed a mean Duke score of 5 (range: 2 to 11), which translated to a low post-exercise risk in 66% and intermediate risk in 34%. A total of seven patients were reported with ischemia by MPI. Three of these patients had high ATPIII pre-test risk scores. Six of these seven patients underwent cardiac catheterization, which showed significant stenosis in one patient with a high pre-test risk of CAD, and indeterminate lesions in three patients (two of whom had high pre-test risk scores). With MPI as a gate keeper for catheterization, no significant, epicardial stenosis was observed in any of the 50 patients (0%, 95% confidence interval 0.0 to 7.1) with low to intermediate pre-test risk of CAD and a negative exercise test. No cardiac events occurred in any patients within a median follow up period of > 1200 d. The added diagnostic value of MPI in patients with low or intermediate risk of CAD and a recent, normal exercise test is marginal.

Development of TlBr detectors for PET imaging.

PubMed

Ariño-Estrada, Gerard; Du, Junwei; Kim, Hadong; Cirignano, Leonard J; Shah, Kanai S; Cherry, Simon R; Mitchell, Gregory S

2018-05-04

Thallium bromide (TlBr) is a promising semiconductor detector material for positron emission tomography (PET) because it can offer very good energy resolution and 3-D segmentation capabilities, and it also provides detection efficiency surpassing that of commonly used scintillators. Energy, timing, and spatial resolution were measured for thin (<1 mm) TlBr detectors. The energy and timing resolution were measured simultaneously for the same planar 0.87 mm-thick TlBr device. An energy resolution of (6.41.3)% at 511 keV was achieved at -400 V bias voltage and at room temperature. A timing resolution of (27.84.1) ns FWHM was achieved for the same operating conditions when appropriate energy gating was applied. The intrinsic spatial resolution was measured to be 0.9 mm FWHM for a TlBr detector with metallic strip contacts of 0.5 mm pitch. As material properties improve, higher bias voltage should improve timing performance. A stack of thin detectors with finely segmented readout can create a modular detector with excellent energy and spatial resolution for PET applications. . © 2018 Institute of Physics and Engineering in Medicine.

Muscle metabolism and activation heterogeneity by combined 31P chemical shift and T2 imaging, and pulmonary O2 uptake during incremental knee-extensor exercise

PubMed Central

Cannon, Daniel T.; Howe, Franklyn A.; Whipp, Brian J.; Ward, Susan A.; McIntyre, Dominick J.; Ladroue, Christophe; Griffiths, John R.; Kemp, Graham J.

2013-01-01

The integration of skeletal muscle substrate depletion, metabolite accumulation, and fatigue during large muscle-mass exercise is not well understood. Measurement of intramuscular energy store degradation and metabolite accumulation is confounded by muscle heterogeneity. Therefore, to characterize regional metabolic distribution in the locomotor muscles, we combined 31P magnetic resonance spectroscopy, chemical shift imaging, and T2-weighted imaging with pulmonary oxygen uptake during bilateral knee-extension exercise to intolerance. Six men completed incremental tests for the following: 1) unlocalized 31P magnetic resonance spectroscopy; and 2) spatial determination of 31P metabolism and activation. The relationship of pulmonary oxygen uptake to whole quadriceps phosphocreatine concentration ([PCr]) was inversely linear, and three of four knee-extensor muscles showed activation as assessed by change in T2. The largest changes in [PCr], [inorganic phosphate] ([Pi]) and pH occurred in rectus femoris, but no voxel (72 cm3) showed complete PCr depletion at exercise cessation. The most metabolically active voxel reached 11 ± 9 mM [PCr] (resting, 29 ± 1 mM), 23 ± 11 mM [Pi] (resting, 7 ± 1 mM), and a pH of 6.64 ± 0.29 (resting, 7.08 ± 0.03). However, the distribution of 31P metabolites and pH varied widely between voxels, and the intervoxel coefficient of variation increased between rest (∼10%) and exercise intolerance (∼30–60%). Therefore, the limit of tolerance was attained with wide heterogeneity in substrate depletion and fatigue-related metabolite accumulation, with extreme metabolic perturbation isolated to only a small volume of active muscle (<5%). Regional intramuscular disturbances are thus likely an important requisite for exercise intolerance. How these signals integrate to limit muscle power production, while regional “recruitable muscle” energy stores are presumably still available, remains uncertain. PMID:23813534

Force and power characteristics of a resistive exercise device for use in space

NASA Astrophysics Data System (ADS)

Berg, Hans E.; Tesch, Per A.

We have developed a non-gravity dependent mechanical device, which provides resistance during coupled concentric and eccentric muscle actions, through the inertia of a spinning fly-wheel (Fly-Wheel Ergometry; FWE). Our research shows that lower-limb FWE exercise can produce forces and thus muscular stress comparable to what is typical of advanced resistance training using free weights. FWE also offers greater training stimuli during eccentric relative to concentric muscle actions, as evidenced by force and electromyographic (EMG) measurements. Muscle use of specific muscle groups, as assessed by the exercise-induced contrast shift of magnetic resonance images, is similar during lower-limb FWE and the barbell squat. Unlike free-weight exercise, FWE allows for maximal voluntary effort in each repetition of an exercise bout. Likewise, FWE exercise, not unassisted free-weight exercise, produces eccentric "overload". Collectively, the inherent features of this resistive exercise device and the results of the physiological evaluations we have performed, suggest that resistance exercise using FWE could be used as an effective exercise counter-measure in space. The flywheel principle can be employed to any exercise configuration and designed into a compact device allowing for exercises stressing those muscles and bone structures, which are thought to be most affected by long-duration spaceflight.

Exercise and type 2 diabetes mellitus: changes in tissue-specific fat distribution and cardiac function.

PubMed

Jonker, Jacqueline T; de Mol, Pieter; de Vries, Suzanna T; Widya, Ralph L; Hammer, Sebastiaan; van Schinkel, Linda D; van der Meer, Rutger W; Gans, Rijk O B; Webb, Andrew G; Kan, Hermien E; de Koning, Eelco J P; Bilo, Henk J G; Lamb, Hildo J

2013-11-01

To prospectively assess the effects of an exercise intervention on organ-specific fat accumulation and cardiac function in type 2 diabetes mellitus. Written informed consent was obtained from all participants, and the study protocol was approved by the medical ethics committee. The study followed 12 patients with type 2 diabetes mellitus (seven men; mean age, 46 years ± 2 [standard error]) before and after 6 months of moderate-intensity exercise, followed by a high-altitude trekking expedition with exercise of long duration. Abdominal, epicardial, and paracardial fat volume were measured by using magnetic resonance (MR) imaging. Cardiac function was quantified with cardiac MR, and images were analyzed by a researcher who was supervised by a senior researcher (4 and 21 years of respective experience in cardiac MR). Hepatic, myocardial, and intramyocellular triglyceride (TG) content relative to water were measured with proton MR spectroscopy at 1.5 and 7 T. Two-tailed paired t tests were used for statistical analysis. Exercise reduced visceral abdominal fat volume from 348 mL ± 57 to 219 mL ± 33 (P < .01), and subcutaneous abdominal fat volume remained unchanged (P = .9). Exercise decreased hepatic TG content from 6.8% ± 2.3 to 4.6% ± 1.6 (P < .01) and paracardial fat volume from 4.6 mL ± 0.9 to 3.7 mL ± 0.8 (P = .02). Exercise did not change epicardial fat volume (P = .9), myocardial TG content (P = .9), intramyocellular lipid content (P = .3), or cardiac function (P = .5). A 6-month exercise intervention in type 2 diabetes mellitus decreased hepatic TG content and visceral abdominal and paracardial fat volume, which are associated with increased cardiovascular risk, but cardiac function was unaffected. Tissue-specific exercise-induced changes in body fat distribution in type 2 diabetes mellitus were demonstrated in this study. RSNA, 2013

Reflex-mediated dynamic neuromuscular stabilization in stroke patients: EMG processing and ultrasound imaging.

PubMed

Yoon, Hyun S; You, Joshua Sung H

2017-07-20

Postural core instability is associated with poor dynamic balance and a high risk of serious falls. Both neurodevelopmental treatment (NDT) and dynamic neuromuscular stabilization (DNS) core stabilization exercises have been used to improve core stability, but the outcomes of these treatments remain unclear. This study was undertaken to examine the therapeutic effects of NDT and DNS core stabilization exercises on muscular activity, core stability, and core muscle thickness. Ten participants (5 healthy adults; 5 hemiparetic stroke patients) were recruited. Surface electromyography (EMG) was used to determine core muscle activity of the transversus abdominis/internal oblique (TrA/IO), external oblique (EO), and rectus abdominis (RA) muscles. Ultrasound imaging was used to measure transversus abdominals/internal oblique (TrA/IO) thickness, and a pressure biofeedback unit (PBU) was used to measure core stability during the DNS and NDT core exercise conditions. Data are reported as median and range and were compared using nonparametric Mann - Whitney U test and Wilcoxon signed rank test at p< 0.05. Both healthy and hemiparetic stroke groups showed greater median EMG amplitude in the TrA/IO muscles, core stability, and muscle thickness values during the DNS exercise condition than during the NDT core exercise condition, respectively (p< 0.05). However, the relative changes in the EMG amplitude, core stability, and muscle thickness values were greater during the DNS exercise condition than during the NDT core exercise condition in the hemiparetic stroke patient group (p< 0.05). Our novel results provide the first clinical evidence that DNS is more effective than NDT in both healthy and hemiparetic stroke subjects to provide superior deep core muscle activation, core stabilization, and muscle thickness. Moreover, such advantageous therapeutic benefits of the DNS core stabilization exercise over the NDT exercise were more apparent in the hemiparetis stroke patients than normal controls.

Changes in transverse relaxation time of quadriceps femoris muscles after active recovery exercises with different intensities.

PubMed

Mukaimoto, Takahiro; Semba, Syun; Inoue, Yosuke; Ohno, Makoto

2014-01-01

The purpose of this study was to examine the changes in the metabolic state of quadriceps femoris muscles using transverse relaxation time (T2), measured by muscle functional magnetic resonance (MR) imaging, after inactive or active recovery exercises with different intensities following high-intensity knee-extension exercise. Eight healthy men performed recovery sessions with four different conditions for 20 min after high-intensity knee-extension exercise on separate days. During the recovery session, the participants conducted a light cycle exercise for 20 min using a cycle (50%, 70% and 100% of the lactate threshold (LT), respectively: active recovery), and inactive recovery. The MR images of quadriceps femoris muscles were taken before the trial and after the recovery session every 30 min for 120 min. The percentage changes in T2 for the rectus femoris and vastus medialis muscles after the recovery session in 50% LT and 70% LT were significantly lower than those in either inactive recovery or 100% LT. There were no significant differences in those for vastus lateralis and vastus intermedius muscles among the four trials. The percentage changes in T2 of rectus femoris and vastus medialis muscles after the recovery session in 50% LT and 70% LT decreased to the values before the trial faster than those in either inactive recovery or 100% LT. Those of vastus lateralis and vastus intermedius muscles after the recovery session in 50% LT and 70% LT decreased to the values before the trial faster than those in 100% LT. Although the changes in T2 after active recovery exercises were not uniform in exercised muscles, the results of this study suggest that active recovery exercise with the intensities below LT are more effective to recover the metabolic state of quadriceps femoris muscles after intense exercise than with either intensity at LT or inactive recovery.

The effect of weight-bearing exercise and non-weight-bearing exercise on gait in rats with sciatic nerve crush injury.

PubMed

Kim, Ki-Hyun; Hwangbo, Gak; Kim, Seong-Gil

2015-04-01

[Purpose] The purpose of this study was to access the effect of weight bearing exercise (treadmill exercise) and non-weight-bearing exercise (swimming exercise) on gait in the recovery process after a sciatic nerve crush injury. [Subjects and Methods] Rats were randomly divided into a swimming group (n=3) with non-weight-bearing exercise after a sciatic nerve crush and a treadmill group (n=3) with weight bearing exercise after a sciatic nerve crush. Dartfish is a program that can analyze and interpret motion through video images. The knee lateral epicondyle, lateral malleolus, and metatarsophalangeal joint of the fifth toe were marked by black dots before recording. [Results] There were significant differences in TOK (knee angle toe off) and ICK (knee angle at initial contact) in the swimming group and in TOK, ICA (ankle angle at initial contact), and ICK in the treadmill group. In comparison between groups, there were significant differences in TOA (ankle angle in toe off) and ICA at the 7th day. [Conclusion] There was no difference between weight bearing and non-weight-bearing exercise in sciatic nerve damage, and both exercises accelerated the recovery process in this study.

In Vivo Noninvasive Analysis of Human Forearm Muscle Function and Fatigue: Applications to EVA Operations and Training Maneuvers

NASA Technical Reports Server (NTRS)

Fotedar, L. K.; Marshburn, T.; Quast, M. J.; Feeback, D. L.

1999-01-01

Forearm muscle fatigue is one of the major limiting factors affecting endurance during performance of deep-space extravehicular activity (EVA) by crew members. Magnetic resonance (MR) provides in vivo noninvasive analysis of tissue level metabolism and fluid exchange dynamics in exercised forearm muscles through the monitoring of proton magnetic resonance imaging (MRI) and phosphorus magnetic resonance spectroscopy (P-31-MRS) parameter variations. Using a space glove box and EVA simulation protocols, we conducted a preliminary MRS/MRI study in a small group of human test subjects during submaximal exercise and recovery and following exhaustive exercise. In assessing simulated EVA-related muscle fatigue and function, this pilot study revealed substantial changes in the MR image longitudinal relaxation times (T2) as an indicator of specific muscle activation and proton flux as well as changes in spectral phosphocreatine-to-phosphate (PCr/Pi) levels as a function of tissue bioenergetic potential.

A functional MRI Exploration of Hamstring Activation During the Supine Bridge Exercise.

PubMed

Bourne, Matthew; Williams, Morgan; Pizzari, Tania; Shield, Anthony

2018-02-01

The single leg supine bridge (SLB) is a commonly employed strengthening exercise and is used as a clinical test for hamstring function in sports, however, little is known about the patterns of muscle activation in this task. To explore these activation patterns, nine healthy, recreationally active males underwent functional magnetic resonance imaging (fMRI) of their thighs at rest and immediately after 5 sets of 10 repetitions of the SLB exercise. Exercise-induced increases in the transverse (T2) relaxation time of the biceps femoris long and short heads, semitendinosus and semimembranosus, were determined via signal intensity changes in pre- and post-exercise images and used as an index of muscle activation. The Bonferroni adjusted alpha was set at p<0.008. The semitendinosus exhibited a greater T2 increase than the biceps femoris short head (p<0.001, d=2.0) and semimembranosus (p=0.001, d=1.2), but not biceps femoris long head (p=0.029, d=0.9). Furthermore, the percentage change in T2 for biceps femoris long head was greater than its short head (p=0.003, d=1.4). During the SLB exercise, the semitendinosus is most selectively targeted and the biceps femoris long head is preferentially activated over its short head. These findings may have implications for the use of the SLB in hamstring injury prevention and rehabilitation programs. © Georg Thieme Verlag KG Stuttgart · New York.

Exercise ameliorates neurocognitive impairments in a translational model of pediatric radiotherapy.

PubMed

Sahnoune, Iman; Inoue, Taeko; Kesler, Shelli R; Rodgers, Shaefali P; Sabek, Omaima M; Pedersen, Steen E; Zawaski, Janice A; Nelson, Katharine H; Ris, M Douglas; Leasure, J Leigh; Gaber, M Waleed

2018-04-09

While cranial radiation therapy (CRT) is an effective treatment, healthy areas surrounding irradiation sites are negatively affected. Frontal lobe functions involving attention, processing speed, and inhibition control are impaired. These deficits appear months to years after CRT and impair quality of life. Exercise has been shown to rejuvenate the brain and aid in recovery post-injury through its effects on neurogenesis and cognition. We developed a juvenile rodent CRT model that reproduces neurocognitive deficits. Next, we utilized the model to test whether exercise ameliorates these deficits. Fischer rats (31 days old) were irradiated with a fractionated dose of 4 Gy × 5 days, trained and tested at 6, 9, and 12 months post-CRT using 5-choice serial reaction time task. After testing, fixed rat brains were imaged using diffusion tensor imaging and immunohistochemistry. CRT caused early and lasting impairments in task acquisition, accuracy, and latency to correct response, as well as causing stunting of growth and changes in brain volume and diffusion. Exercising after irradiation improved acquisition, behavioral control, and processing speed, mitigated the stunting of brain size, and increased brain fiber numbers compared with sedentary CRT values. Further, exercise partially restored global connectome organization, including assortativity and characteristic path length, and while it did not improve the specific regional connections that were lowered by CRT, it appeared to remodel these connections by increasing connectivity between alternate regional pairs. Our data strongly suggest that exercise may be useful in combination with interventions aimed at improving cognitive outcome following pediatric CRT.

Measurement of upper airway pressures in exercising horses with dorsal displacement of the soft palate.

PubMed

Rehder, R S; Ducharme, N G; Hackett, R P; Nielan, G J

1995-03-01

To determine whether abnormal airway pressures have a role in development of dorsal displacement of the soft palate (DDSP), measurements of tracheal and pharyngeal pressures were correlated with nasopharyngeal morphology in exercising horses. Exercising videoendoscopy and measurement of tracheal and pharyngeal pressures were used in 14 clinically normal horses and 19 horses with intermittent DDSP. The pressure signals were superimposed on the videoendoscope image, and both images were saved simultaneously on a videocassette for slow motion analysis to determine the instant displacement occurred in the respiratory cycle. Horses were submitted to an escalating 8-minute high-speed test with a maximal speed of 14 m/s. Compared with clinically normal horses, horses with intermittent DDSP did not have excessively negative inspiratory pressures during exercise. Eight horses displaced the soft palate during inspiration, 4 horses displaced it during expiration, and 7 displaced it by swallowing. Some horses displaced the soft palate at the beginning of the exercise trial, before reaching maximal speed, some horses displaced it at the peak speed, and some horses displaced it when slowing down. Epiglottic size in horses with DDSP was within normal limits, ruling out epiglottic hypoplasia as a cause of DDSP during exercise. Airway pressures were significantly (P < 0.002) altered after DDSP. Pharyngeal and tracheal inspiratory pressures were less negative, whereas pharyngeal expiratory pressure became less positive and tracheal expiratory pressure became more positive after displacement, suggesting a decrease in airflow and an increase in expiratory resistance in the upper airway.

Thallium Toxicity: The Problem; An Analytical Approach; An Antidotal Study

DTIC Science & Technology

1993-05-15

of DMPS to significantly decrease the TI content in 4 target organs suggests it would not be useful in the treatment of T1 poisoning. Accoion For B y...would not be useful in the treatment of Ti poisoning. TABLE OF CONTENTS PAGE ACKNOWLEDGEMENTS ...................................... vii INTRODUCTION...6 PRODUCTION AND USES .............................. 7 ABSORPTION, DISTRIBUTION, EXCRETION ................. 8 MOLECULAR BASIS OF

Remarkable co-catalysis by copper(I) oxide in the palladium catalyzed cross-coupling of arylboronic acids with ethyl bromoacetate.

PubMed

Liu, Xing-xin; Deng, Min-zhi

2002-03-21

Copper(I) oxide can effectively co-catalyze the Suzuki type cross-coupling reactions of arylboronic acids with ethyl bromoacetate. As an alternative protocol for introducing the methylenecarboxy group into functionalized molecules, this reaction occurs in the absence of highly toxic thallium compounds or special ligands and should be convenient and practical.

A successful direct seeding of sugar pine.

Treesearch

William I. Stein

1957-01-01

In southwestern Oregon, the first pilot-scale direct seeding of sugar pine produced a well-stocked stand of seedlings on a 45-acre tract. Control of seed-eating rodents was accomplished by spot-baiting with 1080-treated wheat before seeding, by spot-baiting with thallium sulfate-treated wheat in late December, and by broadcast-baiting with 1080-treated wheat in early...

Scintillator material

DOEpatents

Anderson, D.F.; Kross, B.J.

1992-07-28

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

Scintillator material

DOEpatents

Anderson, D.F.; Kross, B.J.

1994-06-07

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

Application of exercise ECG stress test in the current high cost modern-era healthcare system.

PubMed

Vaidya, Gaurang Nandkishor

Exercise electrocardiogram (ECG) tests boasts of being more widely available, less resource intensive, lower cost and absence of radiation. In the presence of a normal baseline ECG, an exercise ECG test is able to generate a reliable and reproducible result almost comparable to Technitium-99m sestamibi perfusion imaging. Exercise ECG changes when combined with other clinical parameters obtained during the test has the potential to allow effective redistribution of scarce resources by excluding low risk patients with significant accuracy. As we look towards a future of rising healthcare costs, increased prevalence of cardiovascular disease and the need for proper allocation of limited resources; exercise ECG test offers low cost, vital and reliable disease interpretation. This article highlights the physiology of the exercise ECG test, patient selection, effective interpretation, describe previously reported scores and their clinical application in today's clinical practice. Copyright © 2017. Published by Elsevier B.V.

Growth Mechanism of Nanowires: Ternary Chalcogenides

NASA Technical Reports Server (NTRS)

Singh, N. B.; Coriell, S. R.; Hopkins, R. H.; Su, Ching Hua; Arnold, B.; Choa, Fow-Sen; Cullum, Brian

2016-01-01

In the past two decades there has been a large rise in the investment and expectations for nanotechnology use. Almost every area of research has projected improvements in sensors, or even a promise for the emergence of some novel device technologies. For these applications major focuses of research are in the areas of nanoparticles and graphene. Although there are some near term applications with nanowires in photodetectors and other low light detectors, there are few papers on the growth mechanism and fabrication of nanowire-based devices. Semiconductor nanowires exhibit very favorable and promising optical properties, including high transparency and a several order of magnitude better photocurrent than thin film and bulk materials. We present here an overview of the mechanism of nanowire growth from the melt, and some preliminary results for the thallium arsenic selenide material system. Thallium arsenic selenide (TAS) is a multifunctional material combining excellent acousto-optical, nonlinear and radiation detection properties. We observed that small units of (TAS) nanocubes arrange and rearrange at moderate melt undercooling to form the building block of a nanowire. In some cases very long wires (less than mm) are formed. Since we avoided the catalyst, we observed self-nucleation and uncontrolled growth of wires from different places.

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of dissolved arsenic, boron, lithium, selenium, strontium, thallium, and vanadium using inductively coupled plasma-mass spectrometry

USGS Publications Warehouse

Garbarino, John R.

1999-01-01

The inductively coupled plasma?mass spectrometric (ICP?MS) methods have been expanded to include the determination of dissolved arsenic, boron, lithium, selenium, strontium, thallium, and vanadium in filtered, acidified natural water. Method detection limits for these elements are now 10 to 200 times lower than by former U.S. Geological Survey (USGS) methods, thus providing lower variability at ambient concentrations. The bias and variability of the method was determined by using results from spike recoveries, standard reference materials, and validation samples. Spike recoveries at 5 to 10 times the method detection limit and 75 micrograms per liter in reagent-water, surface-water, and groundwater matrices averaged 93 percent for seven replicates, although selected elemental recoveries in a ground-water matrix with an extremely high iron sulfate concentration were negatively biased by 30 percent. Results for standard reference materials were within 1 standard deviation of the most probable value. Statistical analysis of the results from about 60 filtered, acidified natural-water samples indicated that there was no significant difference between ICP?MS and former USGS official methods of analysis.

Sequential injection ionic liquid dispersive liquid-liquid microextraction for thallium preconcentration and determination with flame atomic absorption spectrometry.

PubMed

Anthemidis, Aristidis N; Ioannou, Kallirroy-Ioanna G

2012-08-01

A novel, automatic on-line sequential injection dispersive liquid-liquid microextraction (SI-DLLME) method, based on 1-hexyl-3-methylimidazolium hexafluorophosphate ([Hmim][PF(6)]) ionic liquid as an extractant solvent was developed and demonstrated for trace thallium determination by flame atomic absorption spectrometry. The ionic liquid was on-line fully dispersed into the aqueous solution in a continuous flow format while the TlBr(4)(-) complex was easily migrated into the fine droplets of the extractant due to the huge contact area of them with the aqueous phase. Furthermore, the extractant was simply retained onto the surface of polyurethane foam packed into a microcolumn. No specific conditions like low temperature are required for extractant isolation. All analytical parameters of the proposed method were investigated and optimized. For 15 mL of sample solution, an enhancement factor of 290, a detection limit of 0.86 μg L(-1) and a precision (RSD) of 2.7% at 20.0 μg L(-1) Tl(I) concentration level, was obtained. The developed method was evaluated by analyzing certified reference materials while good recoveries from environmental and biological samples proved that present method was competitive in practical applications.

Derivation of soil screening thresholds to protect chisel-toothed kangaroo rat from uranium mine waste in northern Arizona

USGS Publications Warehouse

Hinck, Jo E.; Linder, Greg L.; Otton, James K.; Finger, Susan E.; Little, Edward E.; Tillitt, Donald E.

2013-01-01

Chemical data from soil and weathered waste material samples collected from five uranium mines north of the Grand Canyon (three reclaimed, one mined but not reclaimed, and one never mined) were used in a screening-level risk analysis for the Arizona chisel-toothed kangaroo rat (Dipodomys microps leucotis); risks from radiation exposure were not evaluated. Dietary toxicity reference values were used to estimate soil-screening thresholds presenting risk to kangaroo rats. Sensitivity analyses indicated that body weight critically affected outcomes of exposed-dose calculations; juvenile kangaroo rats were more sensitive to the inorganic constituent toxicities than adult kangaroo rats. Species-specific soil-screening thresholds were derived for arsenic (137 mg/kg), cadmium (16 mg/kg), copper (1,461 mg/kg), lead (1,143 mg/kg), nickel (771 mg/kg), thallium (1.3 mg/kg), uranium (1,513 mg/kg), and zinc (731 mg/kg) using toxicity reference values that incorporate expected chronic field exposures. Inorganic contaminants in soils within and near the mine areas generally posed minimal risk to kangaroo rats. Most exceedances of soil thresholds were for arsenic and thallium and were associated with weathered mine wastes.

Formic acid electrooxidation on thallium-decorated shape-controlled platinum nanoparticles: an improvement in electrocatalytic activity.

PubMed

Busó-Rogero, Carlos; Perales-Rondón, Juan V; Farias, Manuel J S; Vidal-Iglesias, Francisco J; Solla-Gullon, Jose; Herrero, Enrique; Feliu, Juan M

2014-07-21

Thallium modified shape-controlled Pt nanoparticles were prepared and their electrocatalytic activity towards formic acid electrooxidation was evaluated in 0.5 M sulfuric acid. The electrochemical and in situ FTIR spectroscopic results show a remarkable improvement in the electrocatalytic activity, especially in the low potential region (around 0.1-0.2 V vs. RHE). Cubic Pt nanoparticles modified with Tl were found to be more active than the octahedral Pt ones in the entire range of Tl coverages and potential windows. In situ FTIR spectra indicate that the promotional effect produced by Tl results in the inhibition of the poisoning step leading to COads, thus improving the onset potential for the complete formic acid oxidation to CO2. Chronoamperometric experiments were also performed at 0.2 V to evaluate the stability of the electrocatalysts at constant potential. Finally, experiments with different concentrations of formic acid (0.05-1 M) were also carried out. In all cases, Tl-modified cubic Pt nanoparticles result to be the most active. All these facts reinforce the importance of controlling the surface structure of the electrocatalysts to optimize their electrocatalytic properties.

Computer Simulation of Electron Thermalization in CsI and CsI(Tl)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhiguo; Xie, YuLong; Cannon, Bret D.

2011-09-15

A Monte Carlo (MC) model was developed and implemented to simulate the thermalization of electrons in inorganic scintillator materials. The model incorporates electron scattering with both longitudinal optical and acoustic phonons. In this paper, the MC model was applied to simulate electron thermalization in CsI, both pure and doped with a range of thallium concentrations. The inclusion of internal electric fields was shown to increase the fraction of recombined electron-hole pairs and to broaden the thermalization distance and thermalization time distributions. The MC simulations indicate that electron thermalization, following {gamma}-ray excitation, takes place within approximately 10 ps in CsI andmore » that electrons can travel distances up to several hundreds of nanometers. Electron thermalization was studied for a range of incident {gamma}-ray energies using electron-hole pair spatial distributions generated by the MC code NWEGRIM (NorthWest Electron and Gamma Ray Interaction in Matter). These simulations revealed that the partition of thermalized electrons between different species (e.g., recombined with self-trapped holes or trapped at thallium sites) vary with the incident energy. Implications for the phenomenon of nonlinearity in scintillator light yield are discussed.« less

Thallium release from acid mine drainages: Speciation in river and tap water from Valdicastello mining district (northwest Tuscany).

PubMed

Campanella, Beatrice; Casiot, Corinne; Onor, Massimo; Perotti, Martina; Petrini, Riccardo; Bramanti, Emilia

2017-08-15

In this work we present an advantageous method for the simultaneous separation and detection of Tl(I) and Tl(III) species through ion chromatography coupled with on-line inductively coupled plasma - mass spectrometry. Chromatographic separation between Tl(III) and Tl(I) was achieved in less than two minutes. The method was validated by recovery experiments on real samples, and by comparing the sum of the concentrations of individual Tl species with total thallium values obtained from continuous flow ICP-MS. The experimental procedure offers an accurate, sensitive and interference-free method for Tl speciation at trace levels in environmental samples. This allowed us to investigate the Tl speciation in acid mine drainages (AMD), surface waters and springs in a mining catchment in Valdicastello Carducci (Tuscany, Italy), where severe Tl contamination ad been evidenced previously. This study shows for the first time that Tl(III), in addition to Tl(I), is present in considerable amounts in water samples affected by acid mining outflow, raising the question of the origin of this thermodynamically unstable species. Copyright © 2017 Elsevier B.V. All rights reserved.

Selective Capture of Cesium and Thallium from Natural Waters and Simulated Wastes with Copper Ferrocyanide Functionalized Mesoporous Silica

PubMed Central

Sangvanich, Thanapon; Sukwarotwat, Vichaya; Wiacek, Robert J.; Grudzien, Rafal M.; Fryxell, Glen E.; Addleman, R. Shane; Timchalk, Charles; Yantasee, Wassana

2010-01-01

Copper(II) ferrocyanide on mesoporous silica (FC-Cu-EDA-SAMMS™) has been evaluated against iron(III) hexacyanoferrate(II) (insoluble Prussian Blue) for removing cesium (Cs+) and thallium (Tl+) from natural waters and simulated acidic and alkaline wastes. From pH 0.1 – 7.3, FC-Cu-EDA-SAMMS had greater affinities for Cs and Tl and was less affected by the solution pH, competing cations, and matrices. SAMMS also outperformed Prussian Blue in terms of adsorption capacities (e.g., 21.7 versus 2.6 mg Cs/g in acidic waste stimulant (pH 1.1), 28.3 versus 5.8 mg Tl/g in seawater), and rate (e.g., over 95 wt% of Cs was removed from seawater after 2 min with SAMMS, while only 75 wt% was removed with Prussian Blue). SAMMS also had higher stability (e.g., 2.5 to 13-fold less Fe dissolved from 2 to 24 hr of contact time). In addition to environmental applications, SAMMS has great potential to be used as orally administered drug for limiting the absorption of radioactive Cs and toxic Tl in gastrointestinal tract. PMID:20594644

Kinetic Monte Carlo simulations of excitation density dependent scintillation in CsI and CsI(Tl)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhiguo; Williams, Richard; Grim, Joel

2013-08-15

Nonlinear quenching of electron-hole pairs in the denser regions of ionization tracks created by γ-ray and high-energy electrons is a likely cause of the light yield nonproportionality of many inorganic scintillators. Therefore, kinetic Monte Carlo (KMC) simulations were carried out to investigate the scintillation properties of pure and thallium-doped CsI as a function of electron-hole pair density. The availability of recent experimental data on the excitation density dependence of the light yield of CsI following ultraviolet excitation allowed for an improved parameterization of the interactions between self-trapped excitons (STE) in the KMC model via dipole-dipole Förster transfer. The KMC simulationsmore » reveal that nonlinear quenching occurs very rapidly (within a few picoseconds) in the early stages of the scintillation process. In addition, the simulations predict that the concentration of thallium activators can affect the extent of nonlinear quenching as it has a direct influence on the STE density through STE dissociation and electron scavenging. This improved model will enable more realistic simulations of the nonproportional γ-ray and electron response of inorganic scintillators.« less

Synthesis and characterization of high-Tc superconductors in the Tl-Ca-Ba-Cu-O system

NASA Technical Reports Server (NTRS)

Bansal, Narottam P.; Farrell, D. E.

1989-01-01

Both Tl2Ca2Ba2Cu3O10 and TlCa3BaCu3O8.5 are investigated for superconductivity as a function of the sintering temperature, time, atmosphere, and quench rate in an effort to synthesize the high-Tc superconducting phase in the thallium system. The samples are characterized by electrical resistivity measurements, X-ray diffraction, and scanning electron microscopy. Samples of starting composition Tl2Ca2Ba2Cu3O10 fired in air at 860-900 C and rapidly quenched show a Tc of 96-107 K. In contrast, specimens of starting composition TlCa3BaCu3O8.5 when baked at 900 C and slowly cooled in oxygen superconduct at 116 K and above and consist of Tl2Ca2Ba2Cu3O(10+x) as the dominant phase. The results also show that, in contrast to the case of YBa2Cu3O(7-x), doping with a small concentration of fluorine sharpens the resistive transition and produces a large Tc increase in thallium-based superconductors.

Optimisation of growth of epitaxial Tl 2Ba 2Ca 1Cu 2O 8 superconducting thin films for electronic device applications

NASA Astrophysics Data System (ADS)

Michael, Peter C.; Johansson, L.-G.; Bengtsson, L.; Claeson, T.; Ivanov, Z. G.; Olsson, E.; Berastegui, P.; Stepantsov, E.

1994-12-01

Epitaxial thin films of Tl 2Ba 2Ca 1Cu 2O 8 (Tl-2212) superconductor have been grown on single crystal (100) lanthanum aluminate (LaAlO 3) substrates by a two stage process: laser ablation of a BaCaCuO (0212) sintered target and post-deposition anneal ex-situ in a thallium environment. The films are c-axis oriented with in-plane epitaxy as determined by x-ray diffraction (XRD θ-2θ and φ-scans). Superconducting transition temperatures as high as 105.5K have been obtained both from four-probe resistance and a.c. magnetic susceptibility measurements. Film morphology and chemical composition have been assessed by scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX). Sensitivity of the precursor film to environmental exposure has proven to be a determining factor in the reproducibility of film growth characteristics. The effect of oxygen partial pressure and substrate temperature used in the precursor film synthesis, as well as the thallium annealing temperature and duration, on the growth of Tl-2212 thin films is reported.

Role of relativity in high-pressure phase transitions of thallium.

PubMed

Kotmool, Komsilp; Chakraborty, Sudip; Bovornratanaraks, Thiti; Ahuja, Rajeev

2017-02-20

We demonstrate the relativistic effects in high-pressure phase transitions of heavy element thallium. The known first phase transition from h.c.p. to f.c.c. is initially investigated by various relativistic levels and exchange-correlation functionals as implemented in FPLO method, as well as scalar relativistic scheme within PAW formalism. The electronic structure calculations are interpreted from the perspective of energetic stability and electronic density of states. The full relativistic scheme (FR) within L(S)DA performs to be the scheme that resembles mostly with experimental results with a transition pressure of 3 GPa. The s-p hybridization and the valence-core overlapping of 6s and 5d states are the primary reasons behind the f.c.c. phase occurrence. A recent proposed phase, i.e., a body-centered tetragonal (b.c.t.) phase, is confirmed with a small distortion from the f.c.c. phase. We have also predicted a reversible b.c.t. → f.c.c. phase transition at 800 GPa. This finding has been suggested that almost all the III-A elements (Ga, In and Tl) exhibit the b.c.t. → f.c.c. phase transition at extremely high pressure.

Reaction of 1H-1-oxo-2,4,6,8-tetrakis(tert-butyl)phenoxazine with certain group II-IV metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karsanov, I.V.; Ivakhnenko, E.P.; Khandkarova, V.S.

1987-07-10

It has already been shown that 2-amino-4,6-di(tert-butyl)phenol reacts with 3,5-di(tert-butyl)-o-benzoquinone to form 1H-1-oxo-2,4,6,8-tetrakis(tert-butyl)phenoxazine (I), which is readily reduced by alkali metals to the corresponding semiquinone anion-radical (II), and further to the diamagnetic dianion (IIA). They made use of this ability of (I) to undergo reduction to prepare anion-radical salts with different group II-IV metals in the form of their amalgams. In the EPR spectrum of the anion-radical complex (III) formed in the reduction of (I) by a thallium amalgam, the HFI constants of the unpaired electron with magnetic nuclei of the organic ligand are close to those of the K-saltmore » (II), and a substantial HFI is observed with the /sup 203,205/Tl nuclei. This unequivocally proves that the complex has a semiquinone structure, since an HFI on the /sup 203,205/Tl nuclei of such an order of magnitude is characteristic of o-benzoquinone salts with a thallium cation.« less

Fundamentals of Structural Geology

NASA Astrophysics Data System (ADS)

Pollard, David D.; Fletcher, Raymond C.

2005-09-01

Fundamentals of Structural Geology provides a new framework for the investigation of geological structures by integrating field mapping and mechanical analysis. Assuming a basic knowledge of physical geology, introductory calculus and physics, it emphasizes the observational data, modern mapping technology, principles of continuum mechanics, and the mathematical and computational skills, necessary to quantitatively map, describe, model, and explain deformation in Earth's lithosphere. By starting from the fundamental conservation laws of mass and momentum, the constitutive laws of material behavior, and the kinematic relationships for strain and rate of deformation, the authors demonstrate the relevance of solid and fluid mechanics to structural geology. This book offers a modern quantitative approach to structural geology for advanced students and researchers in structural geology and tectonics. It is supported by a website hosting images from the book, additional colour images, student exercises and MATLAB scripts. Solutions to the exercises are available to instructors. The book integrates field mapping using modern technology with the analysis of structures based on a complete mechanics MATLAB is used to visualize physical fields and analytical results and MATLAB scripts can be downloaded from the website to recreate textbook graphics and enable students to explore their choice of parameters and boundary conditions The supplementary website hosts color images of outcrop photographs used in the text, supplementary color images, and images of textbook figures for classroom presentations The textbook website also includes student exercises designed to instill the fundamental relationships, and to encourage the visualization of the evolution of geological structures; solutions are available to instructors

Which test for CAD should be used in patients with left bundle branch block?

PubMed

Xu, Bo; Cremer, Paul; Jaber, Wael; Moir, Stuart; Harb, Serge C; Rodriguez, L Leonardo

2018-03-01

Exercise stress electrocardiography is unreliable as a test for obstructive coronary artery disease (CAD) if the patient has left bundle branch block. The authors provide an algorithm for using alternative tests: exercise stress echocardiography, dobutamine echocardiography, computed tomographic (CT) angiography, and nuclear myocardial perfusion imaging. Copyright © 2018 Cleveland Clinic.

Using LANDSAT imagery as a basis for the understanding of the physiographic regions of the United States

NASA Technical Reports Server (NTRS)

Blair, R. W., Jr.

1981-01-01

An undergraduate level course in regional geology is described in which map exercises using LANDSAT composite images are required. From these exercises, students lean to appreciate LANDSAT imagery, learn elementary skills in imagery reading and interpretation, in addition to making the association of geography, geology, maps, and imagery.

MR of Toxoplasma encephalitis: Signal characteristics on T2-weighted images and pathologic correlation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brightbill, T.C.; Hensley, G.T.; Ruiz, A.

1996-05-01

Our goal was to determine if there are any T2-weighted MR signal characteristics of Toxoplasma encephalitis that might be useful in diagnosis and/or in gauging the effectiveness of medical therapy. We retrospectively analyzed the MR, CT, thallium-201 SPECT brain scans, and medical records of 27 patients with medically proven (26) and biopsy proven (1) Toxoplasma encephalitis, supplemented by autopsy findings in 4 additional patients, 2 of whom had postmortem MR correlation. The neuropathologic literature was also reviewed. Among the 27 patients, we discovered three distinct imaging patterns. Ten (37%) patients had predominantly T2-weighted hyperintense lesions and had been on medicalmore » therapy an average of 3 days (excluding one outlier). Ten (37%) patients had T2-weighted isointense lesions and had received medical therapy an average of 61 days. Seven (26%) patients had lesions with mixed signal on T2-weighted images and bad been on treatment an average of 6 days. Analysis of autopsy material from the four additional patients revealed the presence of organizing abscesses in three and necrotizing encephalitis in one, while the patient who had a brain biopsy demonstrated both types of pathologic lesions. In both cases having postmortem MRI, organizing abscesses appeared isointense to hypointense on T2-weighted images. There is a definite variation in the appearance of lesions of Toxoplasma encephalitis on T2-weighted images that precludes a definitive diagnosis based on signal characteristics alone. Pathologically, our data suggest that T2-weighted hyperintensity correlates with necrotizing encephalitis and T2-weighted isointensity with organizing abscesses. Furthermore, in patients on medical therapy the T2-weighted MR appearance may be a transition from hyperintensity to isointensity as a function of a positive response to antibiotic treatment, indicating that the signal change might be used to gauge the effectiveness of medical therapy. 15 refs., 6 figs.« less

Validation of a Standalone Smartphone Application for Measuring Heart Rate Using Imaging Photoplethysmography.

PubMed

Poh, Ming-Zher; Poh, Yukkee C

2017-08-01

The aim of this study was to determine the accuracy of a freely available smartphone application, Cardiio app (Cardiio, Inc., Cambridge, MA), to measure heart rate from the finger or face using imaging photoplethysmography, by comparing against an FDA-cleared pulse oximeter at rest, and after moderate to vigorous exercise. A total of 40 healthy adults participated in this study. Participants engaged in a period of rest, followed by 3 min of moderate to vigorous intensity cycling on a stationary bicycle. Heart rate measurements were obtained from both the finger and face of participants using the Cardiio app at rest, immediately after exercise, 1-2 min after exercise, and 2-3 min after exercise. Concurrent heart rate readings using an FDA-cleared finger pulse oximeter served as the reference measurement. There was a very strong agreement between heart rate measurements obtained using the Cardiio app and the pulse oximeter, both at rest (r = 0.99 for finger, r = 0.97 for face) and after exercise (r = 0.99 for finger, r = 0.97 for face). At rest, the accuracy of the Cardiio app was ±1.58 beats per minute (bpm) (or ±2.27%) using the finger mode and ±2.28 bpm (or ±3.17%) for the face mode, compared to the pulse oximeter. After moderate to vigorous exercise, the accuracy of the Cardiio app was ±2.97 bpm (or ±2.79%) using the finger mode and ±5.31 bpm (or ±4.50%) for the face mode, compared to the pulse oximeter. The Cardiio app provided accurate heart rate measurements from the finger and face, both at rest and after exercise.

Toward translating near-infrared spectroscopy oxygen saturation data for the non-invasive prediction of spatial and temporal hemodynamics during exercise

PubMed Central

Ellwein, Laura; Samyn, Margaret M.; Danduran, Michael; Schindler-Ivens, Sheila; Liebham, Stacy; LaDisa, John F.

2016-01-01

Image-based computational fluid dynamics (CFD) studies conducted at rest have shown that atherosclerotic plaque in the thoracic aorta (TA) correlates with adverse wall shear stress (WSS), but there is a paucity of such data under elevated flow conditions. We developed a pedaling exercise protocol to obtain phase contrast magnetic resonance imaging (PC-MRI) blood flow measurements in the TA and brachiocephalic arteries during three-tiered supine pedaling at 130%, 150%, and 170% of resting heart rate (HR), and relate these measurements to noninvasive tissue oxygen saturation (StO2) acquired by near-infrared spectroscopy (NIRS) while conducting the same protocol. Local quantification of WSS indices by CFD revealed low time-averaged WSS on the outer curvature of the ascending aorta and the inner curvature of the descending aorta (dAo) that progressively increased with exercise, but that remained low on the anterior surface of brachiocephalic arteries. High oscillatory WSS observed on the inner curvature of the aorta persisted during exercise as well. Results suggest locally continuous exposure to potentially deleterious indices of WSS despite benefits of exercise. Linear relationships between flow distributions and tissue oxygen extraction calculated from StO2 were found between the left common carotid versus cerebral tissue (r2=0.96) and the dAo versus leg tissue (r2=0.87). A resulting six-step procedure is presented to use NIRS data as a surrogate for exercise PC-MRI when setting boundary conditions for future CFD studies of the TA under simulated exercise conditions. Relationships and ensemble averaged PC-MRI inflow waveforms are provided in an online repository for this purpose. PMID:27376865

Heterogeneity of muscle recruitment pattern during pedaling in professional road cyclists: a magnetic resonance imaging and electromyography study.

PubMed

Hug, François; Bendahan, David; Le Fur, Yann; Cozzone, Patrick J; Grélot, Laurent

2004-07-01

Although a number of studies have been devoted to the analysis of the activity pattern of the muscles involved in pedaling in sedentary subjects and/or amateur cyclists, data on professional cyclists are scarce and the issue of inter-individual differences has never been addressed in detail. In the present series of experiments, we performed a non-invasive investigation using functional magnetic resonance imaging and surface electromyography to determine the pattern of activity of lower limb muscles during two different exhausting pedaling exercises in eight French professional cyclists. Each subject performed an incremental exercise during which electromyographic activity of eight lower limb muscles and respiratory variables were recorded. After a 3-h recovery period, transverse relaxation times (T2) were measured before and just after a standardized constant-load maximal exercise in order to quantify exercise-related T2 changes. The global EMG activity illustrated by the root mean square clearly showed a large inter-individual difference during the incremental exercise regardless of the investigated muscle (variation coefficient up to 81%). In addition, for most of the muscles investigated, the constant-load exercise induced T2 increases, which varied noticeably among the subjects. This high level of variation in the recruitment of lower limb muscles in professional cyclists during both incremental and constant-load exercises is surprising given the homogeneity related to maximal oxygen consumption and training volume. The high degree of expertise of these professional cyclists was not linked to the production of a common pattern of pedaling and our results provide an additional evidence that the nervous system has multiple ways of accomplishing a given motor task, as has been suggested previously by neural control theorists and experimentalists.

Application of cytoplasmic Ca2+ fluorescence imaging techniques to study the molecular mechanisms of exercise-induced fatigue eliminated by Chinese medicine ginseng extract

NASA Astrophysics Data System (ADS)

Liu, Yi; Zhao, Yanping; Zhang, Heming; Liu, Songhao

2009-11-01

The exercise-induced fatigue eliminated by Chinese medicine offers advantages including good efficiency and smaller side-effects, however, the exact mechanisms have not been classified. A lot of literatures indicated the cytosolic free Ca2+ concentrations of skeletal muscle cells increased significantly during exercise-induced fatigue. This study is aimed to establish a rat skeletal muscle cell model of exercise-induced fatigue. We applied cytoplasmic Ca2+ fluorescence imaging techniques to study the molecular mechanisms of exercise-induced fatigue eliminated by Chinese medicine ginseng extract. In our research, the muscle tissues from the newborn 3 days rats were taken out and digested into cells. The cells were randomly divided into the ginseng extract group and the control group. The cells from the two groups were cultured in the medium respectively added 2mg/ml ginseng extract and 2mg/ml D-hanks solution. After differentiating into myotubes, the two groups of cells treated with a fluorescent probe Fluo-3 AM were put on the confocal microscope and the fluorescence intensity of cells pre- and post- stimulation with dexamethasone were detected. It was found that cytoplasmic Ca2+ concentrations of the two groups of cells both increased post-stimulation, however, the increasing amplitude of fluorescence intensity of the ginseng extract group was significantly lower than that of the control group. In conclusion, stimulating the cells with dexamethasone is a kind of workable cell models of exercise-induced fatigue, and the molecular mechanisms of exercise-induced fatigue eliminated by ginseng extract may be connected to regulatating cytosolic free Ca2+ concentrations.

Thallium-isotopic compositions of euxinic sediments as a proxy for global manganese-oxide burial

NASA Astrophysics Data System (ADS)

Owens, Jeremy D.; Nielsen, Sune G.; Horner, Tristan J.; Ostrander, Chadlin M.; Peterson, Larry C.

2017-09-01

Thallium (Tl) isotopes are a new and potentially powerful paleoredox proxy that may track bottom water oxygen conditions based on the global burial flux of manganese oxides. Thallium has a residence time of ∼20 thousand years, which is longer than the ocean mixing time, and it has been inferred that modern oxic seawater is conservative with respect to both concentration and isotopes. Marine sources of Tl have nearly identical isotopic values. Therefore, the Tl sinks, adsorption onto manganese oxides and low temperature oceanic crust alteration (the dominant seawater output), are the primary controls of the seawater isotopic composition. For relatively short-term, ∼million years, redox events it is reasonable to assume that the dominant mechanism that alters the Tl isotopic composition of seawater is associated with manganese oxide burial because large variability in low temperature ocean crust alteration is controlled by long-term, multi-million years, average ocean crust production rates. This study presents new Tl isotope data for an open ocean transect in the South Atlantic, and depth transects for two euxinic basins (anoxic and free sulfide in the water column), the Cariaco Basin and Black Sea. The Tl isotopic signature of open ocean seawater in the South Atlantic was found to be homogeneous with ε205Tl = -6.0 ± 0.3 (±2 SD, n = 41) while oxic waters from Cariaco and the Black Sea are -5.6 and -2.2, respectively. Combined with existing data from the Pacific and Arctic Oceans, our Atlantic data establish the conservatism of Tl isotopes in the global ocean. In contrast, partially- and predominantly-restricted basins reveal Tl isotope differences that vary between open-ocean (-6) and continental material (-2) ε205Tl, scaling with the degree of restriction. Regardless of the differences between basins, Tl is quantitatively removed from their euxinic waters below the chemocline. The burial of Tl in euxinic sediments is estimated to be an order of magnitude less than each of the modern ocean outputs and imparts no isotopic fractionation. Thallium removal into pyrite appears to be associated with a small negative fractionation between -1 and -3 ε205Tl, which renders Tl-depleted waters below the chemocline enriched in isotopically-heavy Tl. Due to the quantitative removal of Tl from euxinic seawater, Tl isotope analyses of the authigenic fraction of underlying euxinic sediments from both the Black Sea and Cariaco Basin capture the Tl isotope value of the oxic portion of their respective water column with no net isotope fractionation. Since the Tl isotope composition of seawater is largely dictated by the relative fraction of Mn-oxide burial versus oceanic crust alteration, we contend that the Tl isotope composition of authigenic Tl in black shales, deposited under euxinic conditions but well-connected to the open ocean, can be utilized to reconstruct the Tl isotope composition of seawater, and thus to reconstruct the global history of Mn-oxide burial.

Thallium isotopes as tracers of recycled materials in subduction zones: Review and new data for lavas from Tonga-Kermadec and Central America

NASA Astrophysics Data System (ADS)

Nielsen, Sune G.; Prytulak, Julie; Blusztajn, Jerzy; Shu, Yunchao; Auro, Maureen; Regelous, Marcel; Walker, Jim

2017-06-01

Sediment is actively being subducted in every convergent margin worldwide. Yet, geochemical data for arc lavas from several subduction zones, such as Northern Tonga and Costa Rica have revealed either attenuated or limited evidence for sediment in their mantle source regions. Here we use thallium (Tl) isotopes to trace slab components in lavas from the Tonga-Kermadec and Central American arcs. In general, both arcs display Tl isotope data that are most compatible with addition of sediment to the sub-arc mantle from the subducting slab. This evidence is particular strong in the Tonga-Kermadec arc where pelagic clays dominate the Tl budget along the entire arc. Contributions from altered oceanic crust as well as the Louisville Seamount chain that subducts underneath Northern Tonga are not visible in Tl isotopes, which is likely due to the very high Tl concentrations found in pelagic sediments outboard of the Tonga-Kermadec arc. Lavas from Central America reveal variable and systematic Tl isotope compositions along-strike. In particular, lavas from Nicaragua are dominated by contributions from sediments, whereas Costa Rican samples reveal a significant altered oceanic crust component with little influence from sediments on thallium isotope composition. The absence of a sediment signature in Costa Rica corresponds with the Cocos Ridge and the seamount province subduction, which results in a thinner sediment cover. Furthermore, the subducted sediment is dominated by carbonates with very low Tl concentrations and, therefore, small amounts of carbonate sediment added to the mantle wedge do not contribute significantly to the overall Tl budget. A review of Tl isotope and concentration data from the Aleutians, Marianas, Tonga-Kermadec and Central American arcs demonstrate that pelagic sediments are detectable in most arcs, whereas altered oceanic crust components only become appreciable when sediment Tl concentrations are very low (e.g. carbonate) or if sediments are no longer a significant component of the subducting slab (e.g. slab melting in Western Aleutians). As such, Tl isotopes are a promising tool to trace sediment subduction although this requires at least some pelagic sediment is present in the subducted sediment package. We suggest that thallium partitioning between the slab and mantle wedge is most likely controlled by retention in phengite or by partitioning into fluids. Residual phengite likely produces high Cs/Tl ratios because Tl should be more compatible in phengite than is Cs, however, this conclusion needs experimental verification. The stability of phengite is lower at higher fluid contents, which results in hyperbolic relationships between Cs/Tl and possible indicators of fluids such as Sr/Nd and Ba/Th. Thus, combined Tl isotopic and elemental systematics not only provide detailed information about the specific slab components that contribute to arc lavas, but also potentially shed light on the mineralogy and physical conditions of subducting slabs.

Exercise-Trained Men and Women: Role of Exercise and Diet on Appetite and Energy Intake

PubMed Central

Howe, Stephanie M.; Hand, Taryn M.; Manore, Melinda M.

2014-01-01

The regulation of appetite and energy intake is influenced by numerous hormonal and neural signals, including feedback from changes in diet and exercise. Exercise can suppress subjective appetite ratings, subsequent energy intake, and alter appetite-regulating hormones, including ghrelin, peptide YY, and glucagon-like peptide 1(GLP-1) for a period of time post-exercise. Discrepancies in the degree of appetite suppression with exercise may be dependent on subject characteristics (e.g., body fatness, fitness level, age or sex) and exercise duration, intensity, type and mode. Following an acute bout of exercise, exercise-trained males experience appetite suppression, while data in exercise-trained women are limited and equivocal. Diet can also impact appetite, with low-energy dense diets eliciting a greater sense of fullness at a lower energy intake. To date, little research has examined the combined interaction of exercise and diet on appetite and energy intake. This review focuses on exercise-trained men and women and examines the impact of exercise on hormonal regulation of appetite, post-exercise energy intake, and subjective and objective measurements of appetite. The impact that low-energy dense diets have on appetite and energy intake are also addressed. Finally, the combined effects of high-intensity exercise and low-energy dense diets are examined. This research is in exercise-trained women who are often concerned with weight and body image issues and consume low-energy dense foods to keep energy intakes low. Unfortunately, these low-energy intakes can have negative health consequences when combined with high-levels of exercise. More research is needed examining the combined effect of diet and exercise on appetite regulation in fit, exercise-trained individuals. PMID:25389897

Exercise-trained men and women: role of exercise and diet on appetite and energy intake.

PubMed

Howe, Stephanie M; Hand, Taryn M; Manore, Melinda M

2014-11-10

The regulation of appetite and energy intake is influenced by numerous hormonal and neural signals, including feedback from changes in diet and exercise. Exercise can suppress subjective appetite ratings, subsequent energy intake, and alter appetite-regulating hormones, including ghrelin, peptide YY, and glucagon-like peptide 1(GLP-1) for a period of time post-exercise. Discrepancies in the degree of appetite suppression with exercise may be dependent on subject characteristics (e.g., body fatness, fitness level, age or sex) and exercise duration, intensity, type and mode. Following an acute bout of exercise, exercise-trained males experience appetite suppression, while data in exercise-trained women are limited and equivocal. Diet can also impact appetite, with low-energy dense diets eliciting a greater sense of fullness at a lower energy intake. To date, little research has examined the combined interaction of exercise and diet on appetite and energy intake. This review focuses on exercise-trained men and women and examines the impact of exercise on hormonal regulation of appetite, post-exercise energy intake, and subjective and objective measurements of appetite. The impact that low-energy dense diets have on appetite and energy intake are also addressed. Finally, the combined effects of high-intensity exercise and low-energy dense diets are examined. This research is in exercise-trained women who are often concerned with weight and body image issues and consume low-energy dense foods to keep energy intakes low. Unfortunately, these low-energy intakes can have negative health consequences when combined with high-levels of exercise. More research is needed examining the combined effect of diet and exercise on appetite regulation in fit, exercise-trained individuals.

Exercise in middle-aged adults: self-efficacy and self-presentational outcomes.

PubMed

McAuley, E; Bane, S M; Mihalko, S L

1995-07-01

Whereas self-efficacy expectations have been identified as important determinants of exercise participation patterns, little empirical work that examines efficacy expectations as outcomes of exercise participation or their theoretical relationship to other psychological outcomes associated with exercise has been conducted. In the context of middle-aged males and females, the present study attempted to integrate social cognitive and impression management perspectives with respect to anxiety associated with exercise. Formerly sedentary subjects participated in a 5-month exercise program with assessments of physique anxiety, efficacy, outcome expectations, and anthropometric variables prior to and following the program. Both acute bouts and long-term participation in exercise resulted in significant increases in self-efficacy. In turn, these changes in efficacy and initial positive outcome expectations were significant predictors of reductions in physique anxiety, even when controlling for the influence of gender and reductions in body fat, weight, and circumferences. The findings are discussed in terms of the implications for structure and content of exercise environments and the utility of the proposed theoretical integration. Strategies for enhancing beliefs regarding health and fitness outcomes associated with exercise rather than appearance outcomes may be required to maximize reductions in negative body image.

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

PubMed

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.

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

PubMed Central

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

2015-01-01

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. PMID:26171383

Imaging popliteal artery disease in young adults with claudication: self-assessment module.

PubMed

Chew, Felix S; Bui-Mansfield, Liem T

2007-09-01

The educational objectives of this self-assessment module on imaging popliteal artery disease in young adults with intermittent claudication are for the participant to exercise, self-assess, and improve his or her knowledge of the imaging and clinical features of popliteal artery entrapment syndrome, cystic adventitial disease,and masses associated with popliteal artery obstruction.

Is Disgust the Driver behind the Selection of Images for UK Tobacco Packets?

ERIC Educational Resources Information Center

Humphris, Gerry; Williams, Brian

2014-01-01

Objective: The use of pictorial warning labels on tobacco packets has gained almost universal international acceptance. In a public consultation exercise in 2006, the Department of Health in England, through a web-based answering system, asked people's preferences of 42 images, asking which images might be effective to encourage tobacco cessation…

Aerobic exercise modulates anticipatory reward processing via the μ-opioid receptor system.

PubMed

Saanijoki, Tiina; Nummenmaa, Lauri; Tuulari, Jetro J; Tuominen, Lauri; Arponen, Eveliina; Kalliokoski, Kari K; Hirvonen, Jussi

2018-06-08

Physical exercise modulates food reward and helps control body weight. The endogenous µ-opioid receptor (MOR) system is involved in rewarding aspects of both food and physical exercise, yet interaction between endogenous opioid release following exercise and anticipatory food reward remains unresolved. Here we tested whether exercise-induced opioid release correlates with increased anticipatory reward processing in humans. We scanned 24 healthy lean men after rest and after a 1 h session of aerobic exercise with positron emission tomography (PET) using MOR-selective radioligand [ 11 C]carfentanil. After both PET scans, the subjects underwent a functional magnetic resonance imaging (fMRI) experiment where they viewed pictures of palatable versus nonpalatable foods to trigger anticipatory food reward responses. Exercise-induced changes in MOR binding in key regions of reward circuit (amygdala, thalamus, ventral and dorsal striatum, and orbitofrontal and cingulate cortices) were used to predict the changes in anticipatory reward responses in fMRI. Exercise-induced changes in MOR binding correlated negatively with the exercise-induced changes in neural anticipatory food reward responses in orbitofrontal and cingulate cortices, insula, ventral striatum, amygdala, and thalamus: higher exercise-induced opioid release predicted higher brain responses to palatable versus nonpalatable foods. We conclude that MOR activation following exercise may contribute to the considerable interindividual variation in food craving and consumption after exercise, which might promote compensatory eating and compromise weight control. © 2018 Wiley Periodicals, Inc.

Longitudinal In Vivo SPECT/CT Imaging Reveals Morphological Changes and Cardiopulmonary Apoptosis in a Rodent Model of Pulmonary Arterial Hypertension

PubMed Central

Paffett, Michael L.; Hesterman, Jacob; Candelaria, Gabriel; Lucas, Selita; Anderson, Tamara; Irwin, Daniel; Hoppin, Jack; Norenberg, Jeffrey; Campen, Matthew J.

2012-01-01

Pulmonary arterial hypertension (PAH) has a complex pathogenesis involving both heart and lungs. Animal models can reflect aspects of the human pathology and provide insights into the development and underlying mechanisms of disease. Because of the variability of most animal models of PAH, serial in vivo measurements of cardiopulmonary function, morphology, and markers of pathology can enhance the value of such studies. Therefore, quantitative in vivo SPECT/CT imaging was performed to assess cardiac function, morphology and cardiac perfusion utilizing 201Thallium (201Tl) in control and monocrotaline-treated rats. In addition, lung and heart apoptosis was examined with 99mTc-Annexin V (99mTc-Annexin) in these cohorts. Following baseline imaging, rats were injected with saline or monocrotaline (50 mg/kg, i.p.) and imaged weekly for 6 weeks. To assess a therapeutic response in an established pulmonary hypertensive state, a cohort of rats received resveratrol in drinking water (3 mg/kg/day) on days 28–42 post-monocrotaline injection to monitor regression of cardiopulmonary apoptosis. PAH in monocrotaline-treated rats was verified by conventional hemodynamic techniques on day 42 (right ventricular systolic pressure (RSVP) = 66.2 mmHg in monocrotaline vs 28.8 mmHg in controls) and in terms of right ventricular hypertrophy (RV/LVS = 0.70 in monocrotaline vs 0.32 in controls). Resveratrol partially reversed both RVSP (41.4 mmHg) and RV/LVS (0.46), as well as lung edema and RV contractility +dP/dtmax. Serial 99mTc-Annexin V imaging showed clear increases in pulmonary and cardiac apoptosis when compared to baseline, which regressed following resveratrol treatment. Monocrotaline induced modest changes in whole-heart perfusion as assessed by 201TI imaging and cardiac morphological changes consistent with septal deviation and enlarged RV. This study demonstrates the utility of functional in vivo SPECT/CT imaging in rodent models of PAH and further confirms the efficacy of resveratrol in reversing established monocrotaline-induced PAH presumably by attenuation of cardiopulmonary apoptosis. PMID:22815866

Muscle dysmorphia: Could it be classified as an addiction to body image?

PubMed Central

FOSTER, ANDREW C.; SHORTER, GILLIAN W.

2015-01-01

Background Muscle dysmorphia (MD) describes a condition characterised by a misconstrued body image in which individuals who interpret their body size as both small or weak even though they may look normal or highly muscular. MD has been conceptualized as a type of body dysmorphic disorder, an eating disorder, and obsessive–compulsive disorder symptomatology. Method and aim Through a review of the most salient literature on MD, this paper proposes an alternative classification of MD – the ‘Addiction to Body Image’ (ABI) model – using Griffiths (2005) addiction components model as the framework in which to define MD as an addiction. Results It is argued the addictive activity in MD is the maintaining of body image via a number of different activities such as bodybuilding, exercise, eating certain foods, taking specific drugs (e.g., anabolic steroids), shopping for certain foods, food supplements, and the use or purchase of physical exercise accessories). In the ABI model, the perception of the positive effects on the self-body image is accounted for as a critical aspect of the MD condition (rather than addiction to exercise or certain types of eating disorder). Conclusions Based on empirical evidence to date, it is proposed that MD could be re-classified as an addiction due to the individual continuing to engage in maintenance behaviours that may cause long-term harm. PMID:25592218

Temporal Changes in Left Ventricular Mechanics: Impact of Bed Rest and Exercise

NASA Technical Reports Server (NTRS)

Scott, J. M.; Downs, M.; Ploutz-Snyder, L. L.

2014-01-01

The use of more sensitive and specific echocardiographic techniques such as speckle tracking imaging may address the current limitations of conventional cardiac imaging techniques to provide insight into the extent and time course of cardiac deconditioning following spaceflight or headdown tilt bed rest (HDTBR). METHODS Speckle tracking assessment of longitudinal, radial, and circumferential strain and twist was used to evaluate the impact of 70 days of HDTBR (n=7) and HDTBR + exercise (n=11) on temporal changes in LV mechanics. Echocardiograms were performed pre (BR-2), during (BR31, 70), and following (BR+4hr) HDTBR. Repeated measures ANOVA was used to evaluate the effect of HDTBR on cardiac variables in control and exercise subjects. RESULTS After sedentary HDTBR, longitudinal (-19.0 +/- 1.8% vs. -14.9 +/- 2.4%) and radial (15.0 +/- 1.9% vs. 11.3 +/- 2.2%) strain and twist (18.0 +/- 4.0deg vs. 17.0 +/- 3.6deg) were significantly impaired. In contrast, exercise preserved LV mechanics, and there were non-significant improvements from BR-2 to BR70 in longitudinal strain (-18.7 +/- 1.5% vs. -20.4 +/- 2.7%), radial strain (13.2 +/- 2.4% vs. 14.2 +/- 1.6%), and twist (16.3 +/- 3.6deg vs. 18.6 +/- 5.9deg). CONCLUSIONS Using speckle tracking echocardiography provides important new insights into temporal changes in LV mechanics during disuse and exercise training.

Prototyping of Remote Experiment and Exercise Systems for an Engineering Education based on World Wide Web

NASA Astrophysics Data System (ADS)

Iwatsuki, Masami; Kato, Yoriyuki; Yonekawa, Akira

State-of-the-art Internet technologies allow us to provide advanced and interactive distance education services. However, we could not help but gather students for experiments and exercises in an education for engineering because large-scale equipments and expensive software are required. On the other hand, teleoperation systems with robot manipulator or vehicle via Internet have been developed in the field of robotics. By fusing these two techniques, we can realize remote experiment and exercise systems for the engineering education based on World Wide Web. This paper presents how to construct the remote environment that allows students to take courses on experiment and exercise independently of their locations. By using the proposed system, users can exercise and practice remotely about control of a manipulator and a robot vehicle and programming of image processing.

Analysis of Thermal Imagery Collected at Grayling II, Grayling, Michigan

DTIC Science & Technology

1994-11-01

during Grayling II exercise ............................................. 36 12 Deciduous (black oak) treeline LWB and SWB IR signatures and air... treeline LWB and SWB IR signaures and air temperature (E3 station, 2 m above ground) during Grayling I exercise ................................. 39 ii...tree. e. Deciduous (black oak) treeline . f. Coniferous (pine) tree. g. Coniferous (pine) treeline . Figure 4 contains color photographs and IR images

Computer Aided Modeling to Determine the Effectiveness of Resistive Exercises as Countermeasures for Bone Mineral Density Loss

NASA Technical Reports Server (NTRS)

Murphy, Benjamin M.

1999-01-01

Due to the loss of gravitational loading, astronauts have a tendency to lose bone mineral density in their lumbar spine and lower extremities on orbit. NASA requires astronauts to perform exercises during space flight to help reduce the amount of demineralization. To test these exercises on earth, 17 week bed rest studies are conducted that consist of specific diet and exercise regimes. Developing a finite element model of these exercises will help to quantify the stress distribution imposed by of each of these exercises. To help develop this model, MRI images are acquired from individuals participating in the bed rest studies. The MRIs can be used to create a subject specific model of each individual for testing. The MRIs are processed in the Magnetic Resonance Imaging Data Transfer System program to develop a three-dimensional finite element model of the femur for evaluation. Modifications were made to the MRIDTS that simplified the model creation process. These modifications made it possible to construct two separate models of different portions of a bone simultaneously and then later connect them manually. This helped alleviate the warping problem associated with the drastic changes in geometry found in some body parts, such as the joints. The code was also modified to incorporate material properties of various bone components into the model. Interior meshing was also incorporated into the program to allow for both the cortical shell and the entire bone to be modeled. A prototype model of the right femur of an adult female is being constructed and tested to determine the feasibility of finite element analysis as a tool for evaluating exercise effectiveness. The model is being run through the ANSYS finite element program on the Alabama Super Computer Network. After the model is validated, models of bedrest subjects can be generated to investigate exercise countermeasures.

Comparison of exercise electrocardiography and stress perfusion CMR for the detection of coronary artery disease in women

PubMed Central

2012-01-01

Background Exercise electrocardiography (ECG) is frequently used in the work-up of patients with suspected coronary artery disease (CAD), however the accuracy is reduced in women. Cardiovascular magnetic resonance (CMR) stress testing can accurately diagnose CAD in women. To date, a direct comparison of CMR to ECG has not been performed. Methods and results We prospectively enrolled 88 consecutive women with chest pain or other symptoms suggestive of CAD. Patients underwent a comprehensive clinical evaluation, exercise ECG, a CMR stress test including perfusion and infarct imaging, and x-ray coronary angiography (CA) within 24 hours. CAD was defined as stenosis ≥70% on quantitative analysis of CA. Exercise ECG, CMR and CA was completed in 68 females (age 66.4 ± 8.8 years, number of CAD risk factors 3.5 ± 1.4). The prevalence of CAD on CA was 29%. The Duke treadmill score (DTS) in the entire group was −3.0 ± 5.4 and was similar in those with and without CAD (−4.5 ± 5.8 and −2.4 ± 5.1; P = 0.12). Sensitivity, specificity and accuracy for CAD diagnosis was higher for CMR compared with exercise ECG (sensitivities 85% and 50%, P = 0.02, specificities 94% and 73%, P = 0.01, and accuracies 91% and 66%, P = 0.0007, respectively). Even after applying the DTS the accuracy of CMR was higher compared to exercise ECG (area under ROC curve 0.94 ± 0.03 vs 0.56 ± 0.07; P = 0.0001). Conclusions In women with intermediate-to-high risk for CAD who are able to exercise and have interpretable resting ECG, CMR stress perfusion imaging has higher accuracy for the detection of relevant obstruction of the epicardial coronaries when directly compared to exercise ECG. PMID:22697372

Potentials of the acousto-optical spectral data processing on a basis of a novel algorithm of the collinear wave heterodyning in a large-aperture KRS-5 crystalline cell

NASA Astrophysics Data System (ADS)

Shcherbakov, Alexandre S.; Maximov, Jewgemij; Sanchez Lucero, Daniel

2010-02-01

Recently proposed modern technique of a precise spectrum analysis within an algorithm of the collinear wave heterodyning implies a two-stage integrated processing, namely, the wave heterodyning of a signal in a square-law nonlinear medium and then the optical processing in the same cell. Technical advantage of this approach is in providing a direct processing of ultra-high-frequency radio-wave signals with essentially improved frequency resolution. This algorithm can be realized on a basis of various physical principles, and we consider an opportunity of involving the potentials of modern acousto-optics for these purposes. From this viewpoint, one needs a large-aperture effective acousto-optical cell, which operates in the Bragg regime and performs the ultra-high-frequency co-directional collinear acoustic wave heterodyning. The technique under consideration imposes specific requirements on the cell's material, namely, a high optical quality of large-size crystalline boules, high-efficient acousto-optical and acoustic interactions, and low group velocity of acoustic waves together with square-low dispersive acoustic losses. We focus our attention on the solid solutions of thallium chalcogenides and take the TlBr-TlI (thallium bromine - thallium iodine) solution, which forms KRS-5 cubic-symmetry crystals with the mass-ratio 58% of TlBr to 42% of TlI. Analysis shows that the acousto-optical cell made of a KRS-5 crystal oriented along the [111] -axis and the corresponding longitudinal elastic mode for producing the dynamic diffractive grating in that crystal can be exploited. With the acoustic velocity of about 1.92 mm/μs and attenuation of approximately 10 dB/(cm GHz2), similar cell is capable to provide an optical aperture of 50 mm and one of the highest figures of acousto-optical merit in solid states in the visible range. Such a cell is rather desirable for applications to direct parallel multi-channel optical spectrum analysis with substantially improved frequency resolution.

Laser-Excited Atomic Fluorescence and Ionization in a Graphite Furnace for the Determination of Metals and Nonmetals

NASA Astrophysics Data System (ADS)

Butcher, David James

1990-01-01

Here is reported novel instrumentation for atomic spectrometry that combined the use of a pulsed laser system as the light source and an electrothermal atomizer as the atom cell. The main goal of the research was to develop instrumentation that was more sensitive for elemental analysis than commercially available instruments and could be used to determine elements in real sample matrices. Laser excited atomic fluorescence spectrometry (LEAFS) in an electrothermal atomizer (ETA) was compared to ETA atomic absorption spectrometry (AAS) for the determination of thallium, manganese, and lead in food and agricultural standard reference materials (SRMs). Compared to ETA AAS, ETA LEAFS has a longer linear dynamic range (LDR) (5-7 orders of magnitude compared to 2-3 orders of magnitude) and higher sensitivity (10 ^{-16} to 10^{ -14} g as compared to 10^{ -13} to 10^{-11} g). Consequently, ETA LEAFS allows elemental analysis to be done over a wider range of concentrations with less dilution steps. Thallium was accurately determined in biological samples by ETA LEAFS at amounts five to one hundred times below the ETA AAS detection limit. ETA AAS and ETA LEAFS were compared for the determination of lead and manganese, and in general, the accuracies and precisions of ETA AAS were the same, with typical precisions between 3% and 6%. Fluorine was determined using laser excited molecular fluorescence spectrometry (LEMOFS) in an ETA. Molecular fluorescence from magnesium fluoride was collected, and the detection limit of 0.3 pg fluorine was two to six orders of magnitude more sensitive than other methods commonly used for the determination of fluorine. Significant interferences from ions were observed, but the sensitivity was high enough that fluorine could be determined in freeze dried urine SRMs by diluting the samples by a factor of one hundred to remove the interferences. Laser enhanced ionization (LEI) in an ETA was used for the determination of metals. For thallium, indium, and lithium, detection limits between 0.7 and 2 pg were obtained, with an LDR of 3.5 orders of magnitude. Sodium was shown to severely depress the indium LEI signal in an ETA.

Eccentric exercise decreases glucose transporter GLUT4 protein in human skeletal muscle.

PubMed Central

Asp, S; Daugaard, J R; Richter, E A

1995-01-01

1. Eccentric exercise causes impaired postexercise glycogen resynthesis. To study whether changes in muscle concentration of the glucose transporter (GLUT4) protein might be involved, seven healthy young men performed one-legged eccentric exercise by resisting knee flexion enforced by a motor-driven device. 2. The GLUT4 protein concentration in the exercised and in the control thigh was unchanged immediately after exercise. On days 1 and 2 after exercise, the GLUT4 protein concentration in the exercised muscle was 68 +/- 10 and 64 +/- 10% (means +/- S.E.M.; P < 0.05), respectively, of the concentration in the control muscle, and had returned to control values on days 4 and 7. 3. The muscle glycogen concentration decreased from 404 +/- 44 to 336 +/- 44 mmol (kg dry wt)-1 (P < 0.05) during exercise. The glycogen concentration remained significantly lower than in the control thigh on days 1 and 2 after exercise but on days 4 and 7 no differences were found. 4. Although no cause-effect relationship was established, these findings may suggest that decreased muscle concentrations of GLUT4 protein, and, hence, a decreased rate of glucose transport into muscle cells, may be involved in the sustained low glycogen concentration seen after eccentric exercise. Images Figure 1 Figure 4 PMID:7738859

MRI assessment of the thigh musculature in dermatomyositis and healthy subjects using diffusion tensor imaging, intravoxel incoherent motion and dynamic DTI.

PubMed

Sigmund, E E; Baete, S H; Luo, T; Patel, K; Wang, D; Rossi, I; Duarte, A; Bruno, M; Mossa, D; Femia, A; Ramachandran, S; Stoffel, D; Babb, J S; Franks, A; Bencardino, J

2018-06-04

Dermatomyositis (DM) is an idiopathic inflammatory myopathy involving severe debilitation in need of diagnostics. We evaluated the proximal lower extremity musculature with diffusion tensor imaging (DTI), intravoxel incoherent motion (IVIM) and dynamic DTI in DM patients and controls and compared with standard clinical workup.  METHODS: In this IRB-approved, HIPAA-compliant study with written informed consent, anatomical, Dixon fat/water and diffusion imaging were collected in bilateral thigh MRI of 22 controls and 27 DM patients in a 3T scanner. Compartments were scored on T1/T2 scales. Single voxel dynamic DTI metrics in quadriceps before and after 3-min leg exercise were measured. Spearman rank correlation and mixed model analysis of variance/covariance (ANOVA/ANCOVA) were used to correlate with T1 and T2 scores and to compare patients with controls. DM patients showed significantly lower pseudo-diffusion and volume in quadriceps than controls. All subjects showed significant correlation between T1 score and signal-weighted fat fraction; tissue diffusion and pseudo-diffusion varied significantly with T1 and T2 score in patients. Radial and mean diffusion exercise response in patients was significantly higher than controls. Static and dynamic diffusion imaging metrics show correlation with conventional imaging scores, reveal spatial heterogeneity, and provide means to differentiate dermatomyositis patients from controls. • Diffusion imaging shows regional differences between thigh muscles of dermatomyositis patients and controls. • Signal-weighted fat fraction and diffusion metrics correlate with T1/T2 scores of disease severity. • Dermatomyositis patients show significantly higher radial diffusion exercise response than controls.

Web-enabled Exercise Generation Tool for Battle Command Training

DTIC Science & Technology

2010-08-01

perceived as fair. Some non-instructional bells and whistles, such as background music and two-dimensional animation, should be judiciously...modify the current image by changing its size or adding a caption (Figure 12). Second, the trainer can upload a new image from his/her computer and...specify properties such as size, caption , image credit, and whether the image is searchable and usable by other trainers (Figure 13). Finally, the

Psychophysiological effects of audiovisual stimuli during cycle exercise.

PubMed

Barreto-Silva, Vinícius; Bigliassi, Marcelo; Chierotti, Priscila; Altimari, Leandro R

2018-05-01

Immersive environments induced by audiovisual stimuli are hypothesised to facilitate the control of movements and ameliorate fatigue-related symptoms during exercise. The objective of the present study was to investigate the effects of pleasant and unpleasant audiovisual stimuli on perceptual and psychophysiological responses during moderate-intensity exercises performed on an electromagnetically braked cycle ergometer. Twenty young adults were administered three experimental conditions in a randomised and counterbalanced order: unpleasant stimulus (US; e.g. images depicting laboured breathing); pleasant stimulus (PS; e.g. images depicting pleasant emotions); and neutral stimulus (NS; e.g. neutral facial expressions). The exercise had 10 min of duration (2 min of warm-up + 6 min of exercise + 2 min of warm-down). During all conditions, the rate of perceived exertion and heart rate variability were monitored to further understanding of the moderating influence of audiovisual stimuli on perceptual and psychophysiological responses, respectively. The results of the present study indicate that PS ameliorated fatigue-related symptoms and reduced the physiological stress imposed by the exercise bout. Conversely, US increased the global activity of the autonomic nervous system and increased exertional responses to a greater degree when compared to PS. Accordingly, audiovisual stimuli appear to induce a psychophysiological response in which individuals visualise themselves within the story presented in the video. In such instances, individuals appear to copy the behaviour observed in the videos as if the situation was real. This mirroring mechanism has the potential to up-/down-regulate the cardiac work as if in fact the exercise intensities were different in each condition.

Smartphone-Based Cardiac Rehabilitation Program: Feasibility Study.

PubMed

Chung, Heewon; Ko, Hoon; Thap, Tharoeun; Jeong, Changwon; Noh, Se-Eung; Yoon, Kwon-Ha; Lee, Jinseok

2016-01-01

We introduce a cardiac rehabilitation program (CRP) that utilizes only a smartphone, with no external devices. As an efficient guide for cardiac rehabilitation exercise, we developed an application to automatically indicate the exercise intensity by comparing the estimated heart rate (HR) with the target heart rate zone (THZ). The HR is estimated using video images of a fingertip taken by the smartphone's built-in camera. The introduced CRP app includes pre-exercise, exercise with intensity guidance, and post-exercise. In the pre-exercise period, information such as THZ, exercise type, exercise stage order, and duration of each stage are set up. In the exercise with intensity guidance, the app estimates HR from the pulse obtained using the smartphone's built-in camera and compares the estimated HR with the THZ. Based on this comparison, the app adjusts the exercise intensity to shift the patient's HR to the THZ during exercise. In the post-exercise period, the app manages the ratio of the estimated HR to the THZ and provides a questionnaire on factors such as chest pain, shortness of breath, and leg pain during exercise, as objective and subjective evaluation indicators. As a key issue, HR estimation upon signal corruption due to motion artifacts is also considered. Through the smartphone-based CRP, we estimated the HR accuracy as mean absolute error and root mean squared error of 6.16 and 4.30bpm, respectively, with signal corruption due to motion artifacts being detected by combining the turning point ratio and kurtosis.

Smartphone-Based Cardiac Rehabilitation Program: Feasibility Study

PubMed Central

Chung, Heewon; Yoon, Kwon-Ha; Lee, Jinseok

2016-01-01

We introduce a cardiac rehabilitation program (CRP) that utilizes only a smartphone, with no external devices. As an efficient guide for cardiac rehabilitation exercise, we developed an application to automatically indicate the exercise intensity by comparing the estimated heart rate (HR) with the target heart rate zone (THZ). The HR is estimated using video images of a fingertip taken by the smartphone’s built-in camera. The introduced CRP app includes pre-exercise, exercise with intensity guidance, and post-exercise. In the pre-exercise period, information such as THZ, exercise type, exercise stage order, and duration of each stage are set up. In the exercise with intensity guidance, the app estimates HR from the pulse obtained using the smartphone’s built-in camera and compares the estimated HR with the THZ. Based on this comparison, the app adjusts the exercise intensity to shift the patient’s HR to the THZ during exercise. In the post-exercise period, the app manages the ratio of the estimated HR to the THZ and provides a questionnaire on factors such as chest pain, shortness of breath, and leg pain during exercise, as objective and subjective evaluation indicators. As a key issue, HR estimation upon signal corruption due to motion artifacts is also considered. Through the smartphone-based CRP, we estimated the HR accuracy as mean absolute error and root mean squared error of 6.16 and 4.30bpm, respectively, with signal corruption due to motion artifacts being detected by combining the turning point ratio and kurtosis. PMID:27551969

Non-invasive measurement using cardiovascular magnetic resonance of changes in pulmonary artery stiffness with exercise.

PubMed

Forouzan, Omid; Warczytowa, Jared; Wieben, Oliver; François, Christopher J; Chesler, Naomi C

2015-12-13

Exercise stress tests are commonly used in clinical settings to monitor the functional state of the heart and vasculature. Large artery stiffness is one measure of arterial function that can be quantified noninvasively during exercise stress. Changes in proximal pulmonary artery stiffness are especially relevant to the progression of pulmonary hypertension (PH), since pulmonary artery (PA) stiffness is the best current predictor of mortality from right ventricular failure. Cardiovascular magnetic resonance (CMR) was used to investigate the effect of exercise stress on PA pulse wave velocity (PWV) and relative area change (RAC), which are both non-invasive measures of PA stiffness, in healthy subjects. All 21 subjects (average age 26 ± 4 years; 13 female and 8 male) used a custom-made MR-compatible stepping device to exercise (two stages of mild-to-moderate exercise of 3-4 min duration each) in a supine position within the confines of the scanner. To measure the cross-sectional area and blood flow velocity in the main PA (MPA), two-dimensional phase-contrast (2D-PC) CMR images were acquired. To measure the reproducibility of metrics, CMR images were analyzed by two independent observers. Inter-observer agreements were calculated using the intraclass correlation and Bland-Altman analysis. From rest to the highest level of exercise, cardiac output increased from 5.9 ± 1.4 L/min to 8.2 ± 1.9 L/min (p < 0.05), MPA PWV increased from 1.6 ± 0.5 m/s to 3.6 ± 1.4 m/s (p < 0.05), and MPA RAC decreased from 0.34 ± 0.11 to 0.24 ± 0.1 (p < 0.05). While PWV also increased from the first to second exercise stage (from 2.7 ± 1.0 m/s to 3.6 ± 1.4 m/s, p < 0.05), there was no significant change in RAC between the two exercise stages. We found good inter-observer agreement for quantification of MPA flow, RAC and PWV. These results demonstrate that metrics of MPA stiffness increase in response to acute moderate exercise in healthy subjects and that CMR exercise stress offers great potential in clinical practice to noninvasively assess vascular function.

Increases in Brain 1H-MR Glutamine and Glutamate Signals Following Acute Exhaustive Endurance Exercise in the Rat

PubMed Central

Świątkiewicz, Maciej; Fiedorowicz, Michał; Orzeł, Jarosław; Wełniak-Kamińska, Marlena; Bogorodzki, Piotr; Langfort, Józef; Grieb, Paweł

2017-01-01

Objective: Proton magnetic resonance spectroscopy (1H-MRS) in ultra-high magnetic field can be used for non-invasive quantitative assessment of brain glutamate (Glu) and glutamine (Gln) in vivo. Glu, the main excitatory neurotransmitter in the central nervous system, is efficiently recycled between synapses and presynaptic terminals through Glu-Gln cycle which involves glutamine synthase confined to astrocytes, and uses 60–80% of energy in the resting human and rat brain. During voluntary or involuntary exercise many brain areas are significantly activated, which certainly intensifies Glu-Gln cycle. However, studies on the effects of exercise on 1H-MRS Glu and/or Gln signals from the brain provided divergent results. The present study on rats was performed to determine changes in 1H-MRS signals from three brain regions engaged in motor activity consequential to forced acute exercise to exhaustion. Method: After habituation to treadmill running, rats were subjected to acute treadmill exercise continued to exhaustion. Each animal participating in the study was subject to two identical imaging sessions performed under light isoflurane anesthesia, prior to, and following the exercise bout. In control experiments, two imaging sessions separated by the period of rest instead of exercise were performed. 1H-NMR spectra were recorded from the cerebellum, striatum, and hippocampus using a 7T small animal MR scanner. Results: Following exhaustive exercise statistically significant increases in the Gln and Glx signals were found in all three locations, whereas increases in the Glu signal were found in the cerebellum and hippocampus. In control experiments, no changes in 1H-MRS signals were found. Conclusion: Increase in glutamine signals from the brain areas engaged in motor activity may reflect a disequilibrium caused by increased turnover in the glutamate-glutamine cycle and a delay in the return of glutamine from astrocytes to neurons. Increased turnover of Glu-Gln cycle may be a result of functional activation caused by forced endurance exercise; the increased rate of ammonia detoxification may also contribute. Increases in glutamate in the cerebellum and hippocampus are suggestive of an anaplerotic increase in glutamate synthesis due to exercise-related stimulation of brain glucose uptake. The disequilibrium in the glutamate-glutamine cycle in brain areas activated during exercise may be a significant contributor to the central fatigue phenomenon. PMID:28197103

Effects of scheduled qigong exercise on pupils' well-being, self-image, distress, and stress.

PubMed

Terjestam, Yvonne; Jouper, John; Johansson, Caroline

2010-09-01

Psychologic problems is increasing among pupils and has become a major problem in Sweden as well as in other Western countries. The aim of this study was to explore whether scheduled qigong exercise could have an effect on well-being at school, psychologic distress, self-image, and general stress. Pupils, 13-14 years, were assigned to either a qigong group or a control group. The qigong group had scheduled qigong 2 times a week for 8 weeks. Self-reported well-being at school, psychologic distress, self-image, and stress were measured pre- and postintervention. The control group had reduced well-being at school during the semester and the qigong group was stable. The qigong group reduced psychologic distress and stress, and had a tendency to improved self-image, whereas no changes were found in the control group. Self-image explains 47% (R(2) = 0.47) of well-being at school, and stress explains 29% (R(2) = 0.29) of psychologic distress. Scheduled qigong, meditative movement, is a possible way to improve well-being at school.