Age, growth, and natural mortality of schoolmaster (Lutjanus apodus) from the southeastern United States.

PubMed

Potts, Jennifer C; Burton, Michael L; Myers, Amanda R

2016-01-01

Ages of schoolmaster ( n = 136) from the southeastern Florida coast from 1981-2015 were determined using sectioned sagittal otoliths. Opaque zones were annular, forming March-July (peaking in May-June). Schoolmaster ranged in age from 1-42 years; the largest fish measured 505 mm total length (TL) and was 19 years old. The oldest fish measured 440 mm TL. Estimated body size relationships for schoolmaster were: W = 9.26 × 10 -6 TL 3.11 ( n = 256, r 2 = 0.95); W = 2.13 × 10 -5 FL 2.99 ( n = 161, r 2 = 0.95); TL = 1.03 FL + 10.36 ( n = 143, r 2 = 0.99); and FL = 0.96 TL - 8.41 ( n = 143, r 2 = 0.99), where W = whole weight in g, FL = fork length in mm, and TL in mm. The fitted von Bertalanffy growth equation was: L t = 482 (1 - e -0.12( t +2.79) ) ( n = 136). Based on published life history relationships, a point estimate of natural mortality for schoolmaster was M = 0.10, while age-specific estimates of M ranged from 1.57-0.18 for ages 1-42.

Length-weight and length-length relationships of common carp (Cyprinus carpio L.) in the middle and southern Iraq provinces

NASA Astrophysics Data System (ADS)

Al-jebory, Taymaa A.; Das, Simon K.; Usup, Gires; Bakar, Y.; Al-saadi, Ali H.

2018-04-01

In this study, length-weight and length-length relationships of common carp (Cyprinus carpio L.) in the middle and southern Iraq provinces were determined. Fish specimens were procured from seven provinces from July to December, 2015. A negative and positive allometric growth pattern was obtained, where the total length (TL) ranged from 25.60 cm to 33.53 cm, and body weight (BW) ranged from 700 g to 1423 g. Meanwhile, the lowest of 1.03 and highest of 3.54 in "b" value was recorded in group F and group C, respectively. Therefore, Fulton condition factor (K) range from 2.57 to 4.94. While, relative condition factor (Kn) was in the ranged of 0.95 to 1.01. A linear relationship between total length (TL) and standard length (SL) among the provinces for fish groups was obtained. The variances in "b" value ranged from 0.10 to 0.93 with correlation coefficient (r2) of 0.02 to 0.97. This research could be used as a guide to study the ecology and biology of common Carp (Cyprinus carpio L.) in the middle and southern Iraq provinces.

Ontogenetic shifts of heart position in snakes.

PubMed

Lillywhite, Harvey B; Lillywhite, Steven M

2017-08-01

Heart position relative to total body length (TL) varies among snakes, with anterior hearts in arboreal species and more centrally located hearts in aquatic or ground-dwelling species. Anterior hearts decrease the cardiac work associated with cranial blood flow and minimize drops in cranial pressure and flow during head-up climbing. Here, we investigate whether heart position shifts intraspecifically during ontogenetic increases in TL. Insular Florida cottonmouth snakes, Agkistrodon conanti, are entirely ground-dwelling and have a mean heart position that is 33.32% TL from the head. In contrast, arboreal rat snakes, Pantherophis obsoleta, of similar lengths have a mean heart position that is 17.35% TL from the head. In both species, relative heart position shifts craniad during ontogeny, with negative slopes = -.035 and -.021% TL/cm TL in Agkistrodon and Pantherophis, respectively. Using a large morphometric data set available for Agkistrodon (N = 192 individuals, 23-140 cm TL), we demonstrate there is an anterior ontogenetic shift of the heart position within the trunk (= 4.56% trunk length from base of head to cloacal vent), independent of head and tail allometry which are both negative. However, in longer snakes > 100 cm, the heart position reverses and shifts caudally in longer Agkistrodon but continues toward the head in longer individuals of Pantherophis. Examination of data sets for two independent lineages of fully marine snakes (Acrochordus granulatus and Hydrophis platurus), which do not naturally experience postural gravity stress, demonstrate both ontogenetic patterns for heart position that are seen in the terrestrial snakes. The anterior migration of the heart is greater in the terrestrial species, even if TL is standardized to that of the longer P. obsoleta, and compensates for about 5 mmHg gravitational pressure head if they are fully upright. © 2017 Wiley Periodicals, Inc.

Does the nephrostomy tract length impact the outcomes of percutaneous nephrolithotomy (PNL)?

PubMed

Astroza, Gaston M; Neisius, Andreas; Tsivian, Matvey; Wang, Agnes J; Preminger, Glenn M; Lipkin, Michael E

2014-12-01

Different factors can determine the outcomes of percutaneous nephrolithotomy (PNL). We analyzed the effect of tract length (TL) on outcomes after PNL. We performed a retrospective review of patients undergoing PNL between 2006 and 2011. Patients with preoperative computed tomography (CT), one percutaneous access tract and follow-up imaging within 3 months were included. TL was defined as distance between the skin to the calyx of puncture as measured on preoperative CT. Measurements were independently performed by two urologists and the average was used for analysis. Stone-free rate (SFR) was defined as zero fragments on follow-up imaging. Factors independently associated with the likelihood of being stone-free after PNL were determined using multivariable analysis adjusted for TL, location of access, the presence of incomplete or complete staghorn calculi and type of follow-up imaging. Complications (Clavien score) were independently assessed. A total of 222 patients were included. Median stone burden and body mass index (BMI) was 239.4 mm(2) and 30.5 [interquartile range (IQR): 25.7-36.2]. The median TL was 85.0 mm (IQR: 70.3-100.0) and highly correlated with BMI (ρ = 0.66, p < 0.001). A total of 101 patients (45.5 %) were stone-free. TL was not associated with SFR (p = 0.53). Clavien 1 and 2 complications occurred in 38 (17 %) while Clavien 3 and 4 complications occurred in 17 (8 %) patients. Multivariable analysis revealed no association between complications and TL even when adjusted for gender. Percutaneous TL is not associated with outcomes of PNL. PNL is a safe and effective treatment for stones in patients with differing body habitus.

Stressful life events and leucocyte telomere length: Do lifestyle factors, somatic and mental health, or low grade inflammation mediate this relationship? Results from a cohort of Danish men born in 1953.

PubMed

Osler, Merete; Bendix, Laila; Rask, Lene; Rod, Naja Hulvej

2016-11-01

Exposure to psychosocial stress is associated with increased risk of a number of somatic and mental disorders with relation to immune system functioning. We aimed to explore whether stressful events in early and recent life was associated with leucocyte telomere length (TL), which is assumed to reflect the accumulated burden of inflammation and oxidative stress occurring during the life course. We specifically aimed to address whether childhood constitutes a sensitive period and how much of the relation between stressful life events and TL is mediated through somatic and mental health, lifestyle, and markers of low-grade inflammation. A cohort of Danish men born in 1953 has been followed since birth in the Metropolit Cohort. These men underwent a health examination including blood sampling in 2010 and a subset of 324 also had a quantitative PCR-based measurement of TL. The relation between stressful life events and TL was analysed using structural equation modelling, which also provided an estimate of the proportion of the total effect mediated by somatic and mental health (cardiovascular disease, body mass and depressive mood), lifestyle factors, and low grade inflammation (C-reactive protein (CRP), interleukin (IL)-6 and IL-10). Total number of stressful events experienced during the life course was not associated with TL. In terms of sensitive periods, we found that number of stressful events in childhood was associated with shorter TL (β per number stressful events in childhood =-0.02(SE=-0.02); P=0.05). This relation was particularly strong for being placed away from home (β=-0.16; P<0.000). Thirty percent of the total effect of stressful events in childhood on TL was mediated by the included variables, with the largest proportion being mediated through depressive mood (16%) and CRP (9%). This study suggests that stressful events in childhood are associated with shorter TL in middle-aged men and that part of this relation is explained by depressive mood and low grade inflammation. Copyright © 2016 Elsevier Inc. All rights reserved.

Beak measurements of octopus ( Octopus variabilis) in Jiaozhou Bay and their use in size and biomass estimation

NASA Astrophysics Data System (ADS)

Xue, Ying; Ren, Yiping; Meng, Wenrong; Li, Long; Mao, Xia; Han, Dongyan; Ma, Qiuyun

2013-09-01

Cephalopods play key roles in global marine ecosystems as both predators and preys. Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic levels. In this study, regressive relationships among beak measurements and body length and weight were determined for an octopus species ( Octopus variabilis), an important endemic cephalopod species in the northwest Pacific Ocean. A total of 193 individuals (63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay, China. Regressive relationships among 6 beak measurements (upper hood length, UHL; upper crest length, UCL; lower hood length, LHL; lower crest length, LCL; and upper and lower beak weights) and mantle length (ML), total length (TL) and body weight (W) were determined. Results showed that the relationships between beak size and TL and beak size and ML were linearly regressive, while those between beak size and W fitted a power function model. LHL and UCL were the most useful measurements for estimating the size and biomass of O. variabilis. The relationships among beak measurements and body length (either ML or TL) were not significantly different between two sexes; while those among several beak measurements (UHL, LHL and LBW) and body weight (W) were sexually different. Since male individuals of this species have a slightly greater body weight distribution than female individuals, the body weight was not an appropriate measurement for estimating size and biomass, especially when the sex of individuals in the stomachs of predators was unknown. These relationships provided essential information for future use in size and biomass estimation of O. variabilis, as well as the estimation of predator/prey size ratios in the diet of top predators.

77 FR 4754 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-31

... recreational annual catch limits (ACLs) have been met before the end of the fishing year for the past 3 fishing... lb (1,134 kg), round weight; and (3) the South Atlantic Unlimited Snapper-Grouper Permit must have... minimum size limit from 12 inches (30.5 cm), total length (TL) to 13 inches (33 cm), TL, and to increase...

Walleye age estimation using otoliths and dorsal spines: Preparation techniques and sampling guidelines based on sex and total length

USGS Publications Warehouse

Dembkowski, Daniel J.; Isermann, Daniel A.; Koenigs, Ryan P.

2017-01-01

We used dorsal spines and otoliths from 735 Walleye Sander vitreus collected from 35 Wisconsin water bodies to evaluate whether 1) otolith and dorsal spine cross sections provided age estimates similar to simpler methods of preparation (e.g., whole otoliths and dorsal spines, cracked otoliths); and 2) between-reader precision and differences between spine and otolith ages varied in relation to total length (TL), sex, and growth rate. Ages estimated from structures prepared using simpler techniques were generally similar to ages estimated using thin sections of dorsal spines and otoliths, suggesting that, in some instances, much of the additional processing time and specialized equipment associated with thin sectioning could be avoided. Overall, between-reader precision was higher for sectioned otoliths (mean coefficient of variation [CV] = 3.28%; standard error [SE] = 0.33%) than for sectioned dorsal spines (mean CV = 9.20%; SE = 0.56%). When using sectioned otoliths for age assignment, between-reader precision did not vary between sexes or growth categories (i.e., fast, moderate, slow), but between-reader precision was higher for females than males when using sectioned dorsal spines. Dorsal spines were generally effective at replicating otolith ages for male Walleye <450 mm TL and female Walleye <600 mm TL, suggesting that dorsal spines can be used to estimate ages for male Walleye <450 mm TL and female Walleye <600 mm TL. If sex is unknown, we suggest dorsal spines be used to estimate ages for Walleye <450 mm TL, but that otoliths be used for fish >450 mm TL. Our results provide useful guidance on structure and preparation technique selection for Walleye age estimation, thereby allowing biologists to develop sampling guidelines that could be implemented using information that is always (TL) or often (sex) available at the time of fish collection.

Adiposity and insulin resistance correlate with telomere length in middle-aged Arabs: the influence of circulating adiponectin.

PubMed

Al-Attas, Omar S; Al-Daghri, Nasser M; Alokail, Majed S; Alfadda, Assim; Bamakhramah, Ahmed; Sabico, Shaun; Pritlove, Dave; Harte, Alison; Tripathi, Gyanendra; McTernan, Philip G; Kumar, Sudhesh; Chrousos, George

2010-10-01

Studies in obesity have implicated adipocytokines in the development of insulin resistance, which in turn may lead to accelerated aging. In this study, we determined associations of chromosomal telomere length (TL) to markers of obesity and insulin resistance in middle-aged adult male and female Arabs with and without diabetes mellitus type 2 (DMT2). One hundred and ninety-three non-diabetic and DMT2 subjects without complications (97 males and 96 females) participated in this cross-sectional study. Clinical data, as well as fasting blood samples, were collected. Serum glucose and lipid profile were determined using routine laboratory methods. Serum insulin, leptin, adiponectin, resistin, tumor necrosis factor-α, and PAI-1 were quantified using customized multiplex assay kits. High sensitive C-reactive protein (hsCRP) and angiotensin II (ANG II) were measured using ELISAs. Circulating leukocyte TL was examined by quantitative real-time PCR. Circulating chromosomal leukocyte TL had significant inverse associations with body mass index (BMI), systolic blood pressure, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), low-density lipoprotein (LDL)- and total cholesterol, ANG II and hsCRP levels. Adiponectin, BMI, systolic blood pressure, and LDL cholesterol predicted 47% of the variance in TL (P<0.0001). HOMA-IR was the most significant predictor for TL in males, explaining 35% of the variance (P=0.01). In females, adiponectin accounted for 28% of the variance in TL (P=0.01). Obesity and insulin resistance are associated with chromosomal TL among adult Arabs. Evidence of causal relations needs further investigation. The positive association of adiponectin to TL has clinical implications as to the possible protective effects of this hormone from accelerated aging.

Adiposity and insulin resistance correlate with telomere length in middle-aged Arabs: the influence of circulating adiponectin

PubMed Central

Al-Attas, Omar S; Al-Daghri, Nasser M; Alokail, Majed S; Alfadda, Assim; Bamakhramah, Ahmed; Sabico, Shaun; Pritlove, Dave; Harte, Alison; Tripathi, Gyanendra; McTernan, Philip G; Kumar, Sudhesh; Chrousos, George

2010-01-01

Objective Studies in obesity have implicated adipocytokines in the development of insulin resistance, which in turn may lead to accelerated aging. In this study, we determined associations of chromosomal telomere length (TL) to markers of obesity and insulin resistance in middle-aged adult male and female Arabs with and without diabetes mellitus type 2 (DMT2). Design and methods One hundred and ninety-three non-diabetic and DMT2 subjects without complications (97 males and 96 females) participated in this cross-sectional study. Clinical data, as well as fasting blood samples, were collected. Serum glucose and lipid profile were determined using routine laboratory methods. Serum insulin, leptin, adiponectin, resistin, tumor necrosis factor-α, and PAI-1 were quantified using customized multiplex assay kits. High sensitive C-reactive protein (hsCRP) and angiotensin II (ANG II) were measured using ELISAs. Circulating leukocyte TL was examined by quantitative real-time PCR. Results Circulating chromosomal leukocyte TL had significant inverse associations with body mass index (BMI), systolic blood pressure, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), low-density lipoprotein (LDL)- and total cholesterol, ANG II and hsCRP levels. Adiponectin, BMI, systolic blood pressure, and LDL cholesterol predicted 47% of the variance in TL (P<0.0001). HOMA-IR was the most significant predictor for TL in males, explaining 35% of the variance (P=0.01). In females, adiponectin accounted for 28% of the variance in TL (P=0.01). Conclusion Obesity and insulin resistance are associated with chromosomal TL among adult Arabs. Evidence of causal relations needs further investigation. The positive association of adiponectin to TL has clinical implications as to the possible protective effects of this hormone from accelerated aging. PMID:20679357

Standard weight (Ws) equations for four rare desert fishes

USGS Publications Warehouse

Didenko, A.V.; Bonar, Scott A.; Matter, W.J.

2004-01-01

Standard weight (Ws) equations have been used extensively to examine body condition in sport fishes. However, development of these equations for nongame fishes has only recently been emphasized. We used the regression-line-percentile technique to develop standard weight equations for four rare desert fishes: flannelmouth sucker Catostomus latipinnis, razorback sucker Xyrauchen texanus, roundtail chub Gila robusta, and humpback chub G. cypha. The Ws equation for flannelmouth suckers of 100-690 mm total length (TL) was developed from 17 populations: log10Ws = -5.180 + 3.068 log10TL. The Ws equation for razorback suckers of 110-885 mm TL was developed from 12 populations: log 10Ws = -4.886 + 2.985 log10TL. The W s equation for roundtail chub of 100-525 mm TL was developed from 20 populations: log10Ws = -5.065 + 3.015 log10TL. The Ws equation for humpback chub of 120-495 mm TL was developed from 9 populations: log10Ws = -5.278 + 3.096 log 10TL. These equations meet criteria for acceptable standard weight indexes and can be used to calculate relative weight, an index of body condition.

Effect of Leukocyte Telomere Length on Total and Regional Brain Volumes in a Large Population-Based Cohort

PubMed Central

King, Kevin S.; Kozlitina, Julia; Rosenberg, Roger N.; Peshock, Ronald M.; McColl, Roderick W.; Garcia, Christine K.

2017-01-01

Importance Telomere length has been associated with dementia and psychological stress, but its relationship with human brain size is unknown. Objective To determine if peripheral blood telomere length is associated with brain volume. Design, Setting, and Participants Peripheral blood leukocyte telomere length and brain volumes were measured for 1960 individuals in the Dallas Heart Study, a population-based, probability sample of Dallas County, Texas, residents, with a median (25th-75th percentile) age of 50 (42-58) years. Global and 48 regional brain volumes were assessed from the automated analysis of magnetic resonance imaging. Main Outcomes and Measures Telomere length and global and regional brain volumes. Results Leukocyte telomere length was associated with total cerebral volume (β [SE], 0.06 [0.01], P <.001) including white and cortical gray matter volume (β [SE], 0.04 [0.01], P = .002; β [SE], 0.07 [0.02], P <.001, respectively), independent of age, sex, ethnicity, and total intracranial volume. While age was associated with the size of most subsegmental regions of the cerebral cortex, telomere length was associated with certain subsegmental regions. Compared with age, telomere length (TL) explained a sizeable proportion of the variance in volume of the hippocampus, amygdala, and inferior temporal region (hippocampus: βTL [SE], 0.08 [0.02], R2, 0.91% vs βage [SE], −0.16 [0.02], R2, 3.80%; amygdala: βTL [SE], 0.08 [0.02], R2, 0.78% vs βage [SE], −0.19 [0.02], R2,4.63%; inferior temporal: βTL [SE], 0.07 [0.02], R2, 0.92% vs βage [SE], −0.14 [0.02], R2, 3.98%) (P <.001 for all). The association of telomere length and the size of the inferior and superior parietal, hippocampus, and fusiform regions was stronger in individuals older than 50 years than younger individuals (inferior parietal: β>50 [SE], 0.13 [0.03], P <.001 vs β≤50 [SE], 0.02 [0.02], P = .51, P for interaction = .001; superior parietal: β>50 [SE], 0.11 [0.03], P <.001 vs β≤50 [SE], 0.01 [0.02], P = .71, P for interaction = .004; hippocampus: β>50 [SE], 0.10 [0.03], P = .004 vs β≤50 [SE], 0.05 [0.02], P = .07, P for interaction = .04; fusiform: β>50 [SE], 0.09 [0.03], P = .002, β≤50 [SE], 0.03 [0.02], P = .31, P for interaction = .03). The volume of the hippocampus, amygdala, superior and inferior temporal, precuneus, lateral orbitofrontal, posterior cingulate, thalamus and ventral diencephalon were independently associated with telomere length after adjustment for all covariates (age, gender, ethnicity, total intracranial volume, body mass index, blood pressure, diabetes, smoking status, and APOE genotype). Conclusions and Relevance To our knowledge, this is the first population-based study to date to evaluate telomere length as an independent predictor of global and regional brain size. Future studies are needed to determine how telomere length and anatomic structural changes are related to cognitive function, dementia, and psychological disease. PMID:25090243

Growth and contribution of stocked channel catfish, Ictalurus punctatus (Rafinesque, 1818): the importance of measuring post-stocking performance

USGS Publications Warehouse

Stewart, David R.; Long, James M.

2015-01-01

In this study it was sought to quantify post-stocking growth, survival, and contribution of advanced size (178 mm total length [TL]) channel catfish Ictalurus punctatus fingerlings, something rarely done. Channel catfish populations were evaluated before (May 2010) and after (May to August 2011 and 2012) stocking. Relative abundance, stocking contribution, and growth were different (P < 0.05) in the two study impoundments (lakes Lone Chimney and Greenleaf, Oklahoma). For fish stocked in Lake Lone Chimney, stocking contribution was lower (3–35%), and average length and weight of stocked fish by age-2 reached 230 mm TL and 85 g, whereas the stocking contribution (84–98%) and growth in length (340 mm TL) and weight (280 g) were higher by age-2 in Lake Greenleaf. Given these unambiguous differences of post-stocking performance, benchmark metrics that represent population-level information such as relative abundance and average length and weight of the sample masked these significant differences, highlighting the importance of marking hatchery-fish and then following them through time to determine the effectiveness of stocking. These results suggest that stock enhancement programmes would benefit from studies that quantify post-stocking performance of hatchery fish.

Complications, Hospital Length of Stay, and Readmission after Total Laryngectomy

PubMed Central

Goepfert, Ryan. P.; Hutcheson, Katherine A.; Lewin, Jan S.; Desai, Neha G.; Zafereo, Mark E.; Hessel, Amy C.; Lewis, Carol M.; Weber, Randal S.; Gross, Neil D.

2018-01-01

Background The purpose of this study was to describe the 30-day incidence of complications after total laryngectomy (TL) in a high-volume institution and their impact on hospital length of stay (LOS) and readmission rates. Methods A retrospective, cohort study of all patients who underwent TL at MD Anderson Cancer Center from January 1, 2010 through June 30, 2013 was conducted. Patient demographics, treatment history, LOS, and 30-day post-TL complications and readmissions were extracted from the medical record. Univariate associations were analyzed and stepwise backward selection methods were used to fit multivariate models. Results 245 patients were included. Complications occurred in 83 patients (33.9%) including 3 (1.2%) deaths. Wound complications occurred in 53 patients (21.6%), of which 34 were pharyngocutaneous fistula (PCF) (13.9% overall). 34 patients (13.9%) were readmitted within 30 days. Multivariate analysis revealed the following: wound complications were associated with former (OR 5.1, p=0.03) and current (OR 5.8, p=0.02) smokers; PCF was associated with prior wide-field radiation (OR 3.1, p=0.01) but not prior narrow-field (larynx only) radiation (OR 1.4, p=0.61); LOS was associated with type of flap (p=0.002) and post-operative hematoma (p=0.05); and readmissions were associated with pre-operative hypoalbuminemia (p=0.003) and post-operative wound complications (p<0.001). Conclusions Complications occurred in nearly one third of TL patients, particularly among patients with poor wound healing risk factors such as prior smoking and radiation. Expectedly, LOS was longer among reconstructed patients. Readmission was associated with hypoalbuminemia and post-operative wound complications. These data inform quality improvement efforts and counseling of high-risk patients undergoing TL. PMID:28026864

Age, growth, mortality and reproductive seasonality of jolthead porgy, Calamus bajonado, from Florida waters.

PubMed

Burton, Michael L; Potts, Jennifer C; Page, Jordan; Poholek, Ariel

2017-01-01

Ages of jolthead porgy ( Calamus bajonado Schneider 1801) ( n  = 635) from Florida commercial and recreational fisheries from 2008-2016 were determined using sectioned sagittal otoliths. We determined, using edge-type analysis, that opaque zones were annular, forming March-June (peaking in April). Jolthead porgy ranged from 1-13 years, and the largest fish measured 680 mm TL (total length, mm). Body size relationships for jolthead porgy were TL  = 1.09 FL  + 20.44 ( n  = 622, r 2  = 0.99), FL  = 0.90 TL -14.26 ( n  = 622, r 2  = 0.99), and W  = 1.1 × 10 -5 TL 3.06 ( n  = 577), where W is total weight (grams, g) and FL is fork length (mm). The von Bertalanffy growth equation for jolthead porgy was L t  = 737(1 -  e -0.14( t +2.02) ) ( n  = 635). Point estimate of natural mortality was M  = 0.32, while age-specific estimates of M ranged from 0.58-0.17 y -1 for ages 1-13. Catch curve analysis estimated the instantaneous rate of total mortality Z  = 0.70, while instantaneous rate of fishing mortality F was 0.38. Macroscopic staging of female gonads indicated the presence of hydrated oocytes from December-March, and GSI data indicates that peak spawning in females occurs during March. This study presents the first published findings of life history parameters for jolthead porgy from the Atlantic waters off the southeastern United States.

Paternal age at birth is an important determinant of offspring telomere length.

PubMed

De Meyer, Tim; Rietzschel, Ernst R; De Buyzere, Marc L; De Bacquer, Dirk; Van Criekinge, Wim; De Backer, Guy G; Gillebert, Thierry C; Van Oostveldt, Patrick; Bekaert, Sofie

2007-12-15

Although evidence supports the function of telomere length (TL) as a marker for biological aging, no major determinants of TL are known besides inheritance, age and gender. Here we validate and, more importantly, assess the impact of paternal age at birth as a determinant for the offspring's peripheral blood leukocyte TL within the Asklepios study population. Telomere restriction fragment length and paternal age information were available for 2433 volunteers (1176 men and 1257 women) aged approximately 35-55 years old. Paternal age at birth was positively associated with offspring TL (offspring age and gender adjusted, P < 10 (-14)). The increase in TL was estimated at 17 base pairs for each supplemental year at birth and was not statistically different between male and female offspring. The effect size of paternal age outweighed the classical TL determinant gender by a factor of 2, demonstrating the large impact. Maternal age at birth was not independently associated with offspring TL. The peculiar interaction between paternal age at birth and inheritance might explain a large part of the genetic component of TL variance on a population level. This finding also provides further proof for the theory that TL is not completely reset in the zygote. Furthermore, as paternal age is subject to demographic evolution, its association with TL might have a substantial impact on the results and comparability of TL within and between epidemiological studies. In conclusion, paternal age is an important determinant for TL, with substantial consequences for future studies.

Dysomma alticorpus, a new species of cutthroat eel from the Gulf of Aqaba, Red Sea (Teleostei: Synaphobranchidae).

PubMed

Fricke, Ronald; Golani, Daniel; Appelbaum-Golani, Brenda; Zajonz, Uwe

2018-02-01

The cutthroat eel Dysomma alticorpus n. sp. is described based on a single specimen collected in a trammel net at a depth of 350m off Eilat, Israel, Gulf of Aqaba, Red Sea. The new species belongs to the Dysomma anguillare species complex, which comprises species possessing a well-developed pectoral fin, intermaxillary teeth, a uniserial row of 7-15 large compound teeth in the lower jaw (which may be followed by a few smaller teeth), and an anteriorly situated anus with the trunk shorter than the head length. It is characterised by a combination of the following characters: origin of the dorsal fin well anterior to the base of the pectoral fin, predorsal length 13.8% TL; preanal length 22.8% TL; three compound teeth on the vomer; head pores: IO 4, SO 3; M 6; POP 0; AD 1, F 0, ST 0; lateral-line pores: predorsal 4, prepectoral 8, preanal 14, total 57-58, the last at the posterior two-thirds of the total length; MVF 7-16-115; total vertebrae 115. Dysomma alticorpus n. sp. is compared with other species of the genus. A revised key to the species of the genera Dysomma and Dysommina is provided. Copyright © 2018 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Hydroacoustics for the discovery and quantification of Nassau grouper ( Epinephelus striatus) spawning aggregations

NASA Astrophysics Data System (ADS)

Egerton, J. P.; Johnson, A. F.; Le Vay, L.; McCoy, C. M.; Semmens, B. X.; Heppell, S. A.; Turner, J. R.

2017-06-01

Fish spawning aggregations (FSAs) are vital life-history events that need to be monitored to determine the health of aggregating populations; this is especially true of the endangered Nassau grouper ( Epinephelus striatus). Hydroacoustics were used to locate Nassau grouper FSAs at sites on the west end of Little Cayman (LCW), and east ends of Grand Cayman (GCE) and Cayman Brac (CBE). Fish abundance and biomass at each FSA were estimated via echo integration and FSA extent. Acoustic mean fish abundance estimates (±SE) on the FSA at LCW (893 ± 459) did not differ significantly from concurrent SCUBA estimates (1150 ± 75). Mean fish densities (number 1000 m-3) were significantly higher at LCW (33.13 ± 5.62) than at the other sites (GCE: 7.01 ± 2.1, CBE: 4.61 ± 1.16). We investigate different acoustic post-processing options to obtain target strength (TS), and we examine the different TS to total length (TL) formulas available. The SCUBA surveys also provided measures of TL through the use of laser callipers allowing development of an in situ TS to TL formula for Nassau grouper at the LCW FSA. Application of this formula revealed mean fish TL was significantly higher at LCW (65.4 ± 0.7 cm) than GCE (60.7 ± 0.4 cm), but not CBE (61.1 ± 2.5 cm). Use of the empirical TS to TL formula resulted in underestimation of fish length in comparison with diver measurements, highlighting the benefits of secondary length data and deriving specific TS to TL formulas for each population. FSA location examined with reference to seasonal marine protected areas (Designated Grouper Spawning Areas) showed FSAs were partially outside these areas at GCE and very close to the boundary at CBE. As FSAs often occur at the limits of safe diving operations, hydroacoustic technology provides an alternative method to monitor and inform future management of aggregating fish species.

Is telomere length associated with mate choice in a songbird with a high rate of extra-pair paternity?

PubMed

Johnsen, Arild; Pauliny, Angela; Lifjeld, Jan T; Blomqvist, Donald

2017-01-01

Telomere length is related to aging in many eukaryotes and the rate of telomere attrition has been suggested to reflect individual genetic quality. Telomere length could thus have implications for mate choice. We investigated telomere length variation in bluethroat Luscinia svecica families with mixed paternity, including social parents, extra-pair fathers and nestlings, testing whether telomere length is associated with social and/or extra-pair mate choice through assortative mating or selection of mates with relatively long telomeres. In adults, relative telomere length (rTL) did not differ between the sexes, nor between two age categories. In chicks, however, rTL decreased with body mass at sampling (an index of nestling age). We found a positive correlation between the rTL of social mates, suggesting assortative mating with respect to telomere length or a correlative thereof. However, extra-pair males did not differ from social mates in rTL, and accordingly there was also no difference between within- and extra-pair young (i.e. half-siblings) when controlling for the effect of mass. We found no relationships between telomere length, age and fitness-related traits in adults, but an intriguing year-difference in telomere length in both sexes. In conclusion, we found no support for the idea that females choose extra-pair males based on their telomere length, but social mate choice seems to be influenced by rTL, possibly through its co-variation with aspects reflecting individual quality, like early arrival at the breeding grounds.

Length-weight relationship and a relative condition factor equation for lake sturgeon (Acipenser fulvescens) from the St Clair River system (Michigan, USA)

USGS Publications Warehouse

Craig, J.M.; Thomas, M.V.; Nichols, S.J.

2005-01-01

Several USA state, federal, and Canadian agencies study lake sturgeon (Acipenser fulvescens) within the St Clair River and Lake St Clair, collectively referred to hereafter as the St Clair River (SCR) system. Previously, there has been no set standard for determining condition for SCR system lake sturgeon. Condition measures the variation from the expected weight for length as an indicator of fatness, general well-being, gonad development, etc. The aim of this project was to determine the length weight relationship of lake sturgeon caught from the SCR system, from which a relative condition factor (Kn) equation could be derived. Total length (TL, mm) and weight (W, kg) were measured for 1074 lake sturgeon (101 males and 16 females were identifiable) collected by setline and bottom trawl from the SCR system in May-September, 1997-2002. Analysis of covariance found no difference in the length-weight relationship between sampling gear or sex. Least-squares regression of log10W ?? log10TL produced the overall equation logW = 3.365logTL - 9.320. Using the exponential form of the slope and y-intercept, relative condition factor for lake sturgeon from the SCR system can be calculated as Kn - W/[(4.786 ?? 10-10)(TL3.365)]. Equations for males and females were also developed. Overall, body condition was significantly correlated with both age and girth; no significant difference in Kn by sex was found. In general, the SCR lake sturgeon population was near the upper ends of growth and condition ranges listed in the literature, comparable with those populations that are at similar latitudes. Although condition factors should be interpreted with caution, proper use of a standard equation provides a non-lethal measure of overall fish health that can be used by biologists and managers in ongoing efforts to restore lake sturgeon throughout the Great Lakes. ?? 2005 Blackwell Verlag, Berlin.

Length-weight relationship and a relative condition factor equation for lake sturgeon (Acipenser fulvescens) from the St. Clair River system (Michigan, USA)

USGS Publications Warehouse

Craig, Jaquelyn M.; Thomas, Michael V.; Nichols, S. Jerrine

2005-01-01

Several USA state, federal, and Canadian agencies study lake sturgeon (Acipenser fulvescens) within the St Clair River and Lake St Clair, collectively referred to hereafter as the St Clair River (SCR) system. Previously, there has been no set standard for determining condition for SCR system lake sturgeon. Condition measures the variation from the expected weight for length as an indicator of fatness, general well-being, gonad development, etc. The aim of this project was to determine the length-weight relationship of lake sturgeon caught from the SCR system, from which a relative condition factor (Kn) equation could be derived. Total length (TL, mm) and weight (W, kg) were measured for 1074 lake sturgeon (101 males and 16 females were identifiable) collected by setline and bottom trawl from the SCR system in May-September, 1997-2002. Analysis of covariance found no difference in the length-weight relationship between sampling gear or sex. Least-squares regression of log10W x log10TL produced the overall equation logW = 3.365logTL - 9.320. Using the exponential form of the slope and y-intercept, relative condition factor for lake sturgeon from the SCR system can be calculated as Kn = W/ [(4.786 x 10-10)(TL3.365)]. Equations for males and females were also developed. Overall, body condition was significantly correlated with both age and girth; no significant difference in Kn by sex was found. In general, the SCR lake sturgeon population was near the upper ends of growth and condition ranges listed in the literature, comparable with those populations that are at similar latitudes. Although condition factors should be interpreted with caution, proper use of a standard equation provides a non-lethal measure of overall fish health that can be used by biologists and managers in ongoing efforts to restore lake sturgeon throughout the Great Lakes.

Telomere length elongation after weight loss intervention in obese adults.

PubMed

Carulli, L; Anzivino, C; Baldelli, E; Zenobii, M F; Rocchi, M B L; Bertolotti, M

2016-06-01

Telomeres may be considered markers of biological aging, shorter telomere length is associated with some age-related diseases; in several studies short telomere length has also been associated to obesity in adults and adolescents. However the relationship between telomere complex functions and obesity is still not clear. Aim of the study was to assess telomere length (TL) in adults' obese subjects before and after weight loss obtained by placement of bioenteric intragastric balloon (BIB) for 6months. We enrolled 42 obese subjects before and after BIB placement as weight loss intervention. Blood samples were collected in order to obtain DNA from leukocyte to measure TL by quantitative PCR. Data were analyzed only in 37 subjects with complete data; all presented important body weight loss (124.06±26.7 vs 105.40±23.14, p<0.001) and more interesting they presented a significant increase in TL (3.58±0.83 vs 5.61±3.29, p<0.001). Moreover we observed a significant positive correlation between TL elongation and weight loss (r=0.44, p=0.007) as well as an inverse correlation between TL at baseline and TL elongation (r=-0.35, p=0.03).The predictors of TL elongation were once again weight loss and short TL at baseline (respectively p=0.007 and p=0.003). Our study shows that weight loss is associated to telomere lengthening in a positive correlation: the greater weight loss the greater telomere lengthening; moreover telomere lengthening is more significant in those subjects with shortest telomeres at baseline. Copyright © 2016 Elsevier Inc. All rights reserved.

Setting the Trajectory: Racial Disparities in Newborn Telomere Length

PubMed Central

Drury, Stacy S.; Esteves, Kyle; Hatch, Virginia; Woodbury, Margaret; Borne, Sophie; Adamski, Alys; Theall, Katherine P.

2015-01-01

Objective To explore racial differences in newborn telomere length (TL) and the effect moderation of the sex of the infant while establishing the methodology for the use of newborn blood spots for telomere length analyses. Study design Pregnant mothers were recruited from the Greater New Orleans area. TL was determined using MMQ-PCR on DNA extracted from infant blood spots. Demographic data and other covariates were obtained via maternal report prior to infant birth. Birth outcome data were obtained from medical records and maternal report. Results Black infants weighed significantly less than white infants at birth, and had significantly longer TL than White infants (p=0.0134), with the strongest effect observed in Black female infants. No significant differences in gestational age were present. Conclusions Significant racial differences in TL were present at birth in this sample, even after controlling for a range of birth outcomes and demographic factors. As longer initial TL is predictive of more rapid TL attrition across the life course, these findings provide evidence that, even at birth, biological vulnerability to early life stress may differ by race and sex. PMID:25681203

Structural investigation of the substituted pyrochlore AgSbO3 through total scattering techniques.

PubMed

Laurita, Geneva; Page, Katharine; Sleight, A W; Subramanian, M A

2013-10-07

Polycrystalline samples of the pyrochlore series Ag(1-x)M(n)(x)SbO(3+x[(n-1)/2]) (M = Na, K, and Tl) have been structurally analyzed through total scattering techniques. The upper limits of x obtained were 0.05 for Na, 0.16 for K, and 0.17 for Tl. The Ag(+) cation occupies a site with inversion symmetry on a 3-fold axis. When the smaller Na(+) cation substitutes for Ag(+), it is displaced by about 0.6 Å perpendicular to the 3-fold axis to achieve some shorter Na-O bond distances. When the larger Tl(+) cation substitutes for Ag(+), it is displaced by about 1.14 Å along the 3-fold axis and achieves an environment typical of a lone pair cation. Some of the Tl(3+) from the precursor remains unreduced, leading to a formula of Ag(0.772(1))Tl(+)(0.13(2))Tl(3+)(0.036(1))SbO(3.036(1)). The position of the K(+) dopant was effectively modeled assuming that K(+) occupied the same site as Ag(+). The expansion of the lattice caused by substitution of the larger K(+) and Tl(+) cations results in longer Ag-O bond lengths, which would reduce the overlap of the Ag 4d and O 2p orbitals that compose the valence band maximum. Substitution of the smaller Na(+) results in a decrease in the Ag-O bond distance, thus increasing the overlap of the Ag 4d and O 2p orbitals. This will have a direct influence on the band composition and observed properties of this material of interest.

Dietary patterns, food groups and telomere length: a systematic review of current studies.

PubMed

Rafie, N; Golpour Hamedani, S; Barak, F; Safavi, S M; Miraghajani, M

2017-02-01

Telomere length (TL) is recognized as a biomarker of aging and shorter telomeres are linked with shorter lifespan. Inter-individual variability in telomere length is highly heritable. However, there has been a resurgence of interest in the controversial relationship between diet and TL. Evaluating the impact of diet at the food group and dietary pattern level will provide greater insight into the effect of diet on TL dynamics, which are of significant importance in health and longevity. This article reports the first systematic review of the relation between food groups, dietary patterns and TL in human populations based on PRISMA guidelines. PubMed, Science Direct, The Cochrane Library and Google Scholar databases were electronically searched for all relevant studies, up to November 2015. Among the 17 included studies, 3 and 10 of them were regarding the effect of dietary patterns and various food groups on TL, respectively. Also, in 4 studies, both dietary patterns and different food groups were assessed in relation to TL. Mediterranean dietary pattern was related to longer TL in 3 studies. Five studies indicated beneficial effect of fruits or vegetables on TL. In 7 studies, a reverse association between TL and intake of cereals, processed meat, and fats and oils was reported. Our systematic review supports the health benefits of adherence to Mediterranean diet on TL. Except for the fruits and vegetables, which showed positive association with TL, results were inconsistent for other dietary factors. Also, certain food categories including processed meat, cereals and sugar-sweetened beverages may be associated with shorter TLs. However, additional epidemiological evidence and clinical trials should be considered in future research in order to develop firm conclusions in this regard.

Racial and Socioeconomic Variation in Genetic Markers of Telomere Length: A Cross-Sectional Study of U.S. Older Adults.

PubMed

Hamad, Rita; Tuljapurkar, Shripad; Rehkopf, David H

2016-09-01

Shorter telomere length (TL) has been associated with stress and adverse socioeconomic conditions, yet U.S. blacks have longer TL than whites. The role of genetic versus environmental factors in explaining TL by race and socioeconomic position (SEP) remains unclear. We used data from the U.S. Health and Retirement Study (N=11,934) to test the hypothesis that there are differences in TL-associated SNPs by race and SEP. We constructed a TL polygenic risk score (PRS) and examined its association with race/ethnicity, educational attainment, assets, gender, and age. U.S. blacks were more likely to have a lower PRS for TL, as were older individuals and men. Racial differences in TL were statistically accounted for when controlling for population structure using genetic principal components. The GWAS-derived SNPs for TL, however, may not have consistent associations with TL across different racial/ethnic groups. This study showed that associations of race/ethnicity with TL differed when accounting for population stratification. The role of race/ethnicity for TL remains uncertain, however, as the genetic determinants of TL may differ by race/ethnicity. Future GWAS samples should include racially diverse participants to allow for better characterization of the determinants of TL in human populations. Copyright © 2016 Forschungsgesellschaft für Arbeitsphysiologie und Arbeitschutz e.V. Published by Elsevier B.V. All rights reserved.

Reproduction and early-life accommodations of landlocked alewives to a southern range extension

USGS Publications Warehouse

Nigro, A.A.; Ney, John J.

1982-01-01

Reproduction and first-year growth and food habits of landlocked alewives Alosa pseudoharengus in Claytor Lake, Virginia were examined and compared to descriptions for populations in the species' established New England-Great Lakes range. Alewives in mesothermal (2–27 C) Claytor Lake are shorter-lived (3 years) but grow faster, mature earlier (age 1), and have higher relative and absolute fecundities than have been reported for populations in colder northern waters. The 1979 spawning period extended from early May to early August, beginning at least 1 month earlier and lasting 4–9 weeks longer than in northern lakes. Changes in ovary condition during the spawning period suggest that alewives may be fractional spawners. Evidence of spawning was found in littoral areas throughout the lower 15 km of the reservoir. Growth in length of age-0 Claytor Lake alewives was linear through September and terminated in late autumn. Total first-year growth was reduced in 1979 (maximum of 130 mm total length, TL) from previous years (average of 160 mm TL), although it was substantially greater than recorded in the Great Lakes and the northeastern United States. The longer growing season, rather than accelerated in-season growth, appears to account for larger size achieved in Claytor Lake. High annual growth limits predation by Claytor Lake game fish on early spawned age-0 alewives by late summer. As elsewhere, larval and juvenile alewives (6–70 mm TL) fed primarily on copepods and cladocerans. Age-0 alewives longer than 35 mm TL demonstrated positive size-selection for cyclopoid copepods comparable to that shown by adults. Our findings suggest that self-sustaining alewife populations can be established in many inland waters but raise concerns regarding their forage value and community impacts.

Comparison of posterior retroperitoneal and transabdominal lateral approaches in robotic adrenalectomy: an analysis of 200 cases.

PubMed

Kahramangil, Bora; Berber, Eren

2018-04-01

Although numerous studies have been published on robotic adrenalectomy (RA) in the literature, none has done a comparison of posterior retroperitoneal (PR) and transabdominal lateral (TL) approaches. The aim of this study was to compare the outcomes of robotic PR and TL adrenalectomy. This is a retrospective analysis of a prospectively maintained database. Between September 2008 and January 2017, perioperative outcomes of patients undergoing RA through PR and TL approaches were recorded into an IRB-approved database. Clinical and perioperative parameters were compared using Student's t test, Wilcoxon rank-sum test, and χ 2 test. Multivariate regression analysis was performed to determine factors associated with total operative time. 188 patients underwent 200 RAs. 110 patients were operated through TL and 78 patients through PR approach. Overall, conversion rate to open was 2.5% and 90-day morbidity 4.8%. The perioperative outcomes of TL and PR approaches were similar regarding estimated blood loss, rate of conversion to open, length of hospital stay, and 90-day morbidity. PR approach resulted in a shorter mean ± SD total operative time (136.3 ± 38.7 vs. 154.6 ± 48.4 min; p = 0.005) and lower visual analog scale pain score on postoperative day #1 (4.3 ± 2.5 vs. 5.4 ± 2.4; p = 0.001). After excluding tumors larger than 6 cm operated through TL approach, the difference in operative times persisted (136.3 ± 38.7 vs. 153.7 ± 45.7 min; p = 0.009). On multivariate regression analysis, increasing BMI and TL approaches were associated with longer total operative time. This study shows that robotic PR and TL approaches are equally safe and efficacious. With experience, shorter operative time and less postoperative pain can be achieved with PR technique. This supports the preferential utilization of PR approach in high-volume centers with enough experience.

Embryonic and postnatal telomere length decrease with ovulation order within clutches

PubMed Central

Noguera, José C.; Metcalfe, Neil B.; Reichert, Sophie; Monaghan, Pat

2016-01-01

Telomere length (TL) in early life has been found to be predictive of subsequent lifespan. Factors such as parental TL, parental age and environmental conditions during development have been shown to contribute to the observed variation in TL among individuals. One factor that has not hitherto been considered is ovulation order, although it is well established that the last hatched/born offspring in a brood or litter often show relatively poor subsequent performance. We examined the within- and across-clutch effect of ovulation order on TL in embryos of zebra finches experiencing the same controlled incubation conditions (N = 151), and tested whether any such ovulation order effects remained detectable in adults (N = 122). Irrespective of clutch and egg size, TL in early-stage embryos (72 h incubation) markedly decreased with within-clutch ovulation order; the difference in TL of first and last-laid embryos was equivalent to the average within-individual telomere loss over the entire period of nestling and juvenile life. This ovulation-order effect occurred only within but not across clutches, and was still evident in adults. Given that TL in early life predicts lifespan, our results suggest that parental effects on telomere length could contribute to the known poor performance of later-ovulated family members. PMID:27174767

Study of telomere length and different markers of oxidative stress in patients with Parkinson's disease.

PubMed

Watfa, G; Dragonas, C; Brosche, T; Dittrich, R; Sieber, C C; Alecu, C; Benetos, A; Nzietchueng, R

2011-04-01

Many studies have shown that short telomere length (TL) is associated with high oxidative stress and various age-related diseases. Parkinson's disease (PD) is an age-related disease, and although its pathogenic mechanism is uncertain, oxidative stress is believed to be implicated in this pathology. The aim of this case-control study was to assess both TL and the different markers of oxidative stress in elderly patients with PD compared to age control subjects. 20 PD patients and 15 age-matched controls, >65 years were studied. TL was measured by Southern blotting from DNA samples extracted from white blood cells. Superoxide dismutase (SOD) activity and plasma levels of total glutathione and protein carbonyls were determined. There was a trend for lower TL in PD patients: 6.06 ± 0.81 kb in PD versus 6.45 ± 0.73 kb in controls (p = 0.08). No significant difference was found between the two groups in terms of oxidative stress markers. In controls, age was the main determinant of telomere shortening (r = -0.547; p = 0.03) whereas, in PD patients, telomere shortening was mainly dependent on plasmatic concentrations of carbonyl proteins (r= -0.544; p=0.044). In PD patients, a negative association was observed between plasma carbonyl protein levels and SOD activity (r= -0.622, p=0.004). In PD, TL is shorter in presence of high oxidative stress as measured by carbonyl protein levels. The absence of telomere attrition with age among patients with PD could reflect a telomere regulation by mechanisms other than age.

Race/Ethnicity, Poverty, Urban Stressors and Telomere Length in a Detroit Community-Based Sample

PubMed Central

Geronimus, Arline T.; Pearson, Jay A.; Linnenbringer, Erin; Schulz, Amy J.; Reyes, Angela G.; Epel, Elissa S.; Lin, Jue; Blackburn, Elizabeth H.

2015-01-01

Residents of distressed urban areas suffer early aging-related disease and excess mortality. Using a community-based participatory research approach in a collaboration between social researchers and cellular biologists, we collected a unique data set of 239 black, white, or Mexican adults from a stratified, multi-stage probability sample of three Detroit neighborhoods. We drew venous blood and measured Telomere Length (TL), an indicator of stress-mediated biological aging, linking respondents’ TL to their community survey responses. We regressed TL on socioeconomic, psychosocial, neighborhood, and behavioral stressors, hypothesizing and finding an interaction between poverty and racial/ethnic group. Poor whites had shorter TL than nonpoor whites; poor and nonpoor blacks had equivalent TL; poor Mexicans had longer TL than nonpoor Mexicans. Findings suggest unobserved heterogeneity bias is an important threat to the validity of estimates of TL differences by race/ethnicity. They point to health impacts of social identity as contingent, the products of structurally-rooted biopsychosocial processes. PMID:25930147

Race-Ethnicity, Poverty, Urban Stressors, and Telomere Length in a Detroit Community-based Sample.

PubMed

Geronimus, Arline T; Pearson, Jay A; Linnenbringer, Erin; Schulz, Amy J; Reyes, Angela G; Epel, Elissa S; Lin, Jue; Blackburn, Elizabeth H

2015-06-01

Residents of distressed urban areas suffer early aging-related disease and excess mortality. Using a community-based participatory research approach in a collaboration between social researchers and cellular biologists, we collected a unique data set of 239 black, white, or Mexican adults from a stratified, multistage probability sample of three Detroit neighborhoods. We drew venous blood and measured telomere length (TL), an indicator of stress-mediated biological aging, linking respondents' TL to their community survey responses. We regressed TL on socioeconomic, psychosocial, neighborhood, and behavioral stressors, hypothesizing and finding an interaction between poverty and racial-ethnic group. Poor whites had shorter TL than nonpoor whites; poor and nonpoor blacks had equivalent TL; and poor Mexicans had longer TL than nonpoor Mexicans. Findings suggest unobserved heterogeneity bias is an important threat to the validity of estimates of TL differences by race-ethnicity. They point to health impacts of social identity as contingent, the products of structurally rooted biopsychosocial processes. © American Sociological Association 2015.

Telomere length in children environmentally exposed to low-to-moderate levels of lead

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

Pawlas, Natalia, E-mail: n-pawlas@wp.pl; Płachetka, Anna; Kozłowska, Agnieszka

Shorter relative telomere length in peripheral blood is a risk marker for some types of cancers and cardiovascular diseases. Several environmental hazards appear to shorten telomeres, and this shortening may predispose individuals to disease. The aim of the present cross-sectional study was to assess the effect of environmental exposure to lead on relative telomere length (rTL) in children. A cohort of 99 8-year-old children was enrolled from 2007–2010. Blood lead concentrations (B-Pb) were measured by graphite furnace atomic absorption spectrometry, and blood rTL was measured by quantitative PCR. The geometric mean of B-Pb was 3.28 μg/dl (range: 0.90–14.2), and themore » geometric mean of rTL was 1.08 (range: 0.49–2.09). B-Pb was significantly inversely associated with rTL in the children (r{sub S} = − 0.25, p = 0.013; in further analyses both log-transformed-univariate regression analysis β = − 0.13, p = 0.026, and R{sup 2}adj 4%; and β = − 0.12, p = 0.056 when adjusting for mothers' smoking during pregnancy, Apgar score, mother's and father's ages at delivery, sex and mother's education, R{sup 2}adj 12%, p = 0.011). The effect of lead remained significant in children without prenatal tobacco exposure (N = 87, r{sub S} = − 0.24, p = 0.024; in further analyses, β = − 0.13, p = 0.029, and R{sup 2}adj 4%). rTL was not affected by sex, the concentrations of other elements in the blood (i.e., cadmium and selenium concentrations), or oxidative injury parameters (total antioxidant status, 8-hydroxydeoxyguanosine and thiobarbituric acid-reactive substances). Lead exposure in childhood appears to be associated with shorter telomeres, which might contribute to diseases, such as cardiovascular disease. The inverse association between blood lead level and the telomeres in children emphasizes the importance of further reducing lead levels in the environment. - Highlights: • This cross-sectional study analyzes the association between environmental lead exposure and telomere length in children. • Blood lead concentrations were inversely associated with relative telomere length in 8-year-old children. • Environmental lead exposure during childhood might contribute to telomere shortening, and in turn, future risk for disease.« less

Social disadvantage, genetic sensitivity, and children’s telomere length

PubMed Central

Mitchell, Colter; Hobcraft, John; McLanahan, Sara S.; Siegel, Susan Rutherford; Berg, Arthur; Brooks-Gunn, Jeanne; Garfinkel, Irwin; Notterman, Daniel

2014-01-01

Disadvantaged social environments are associated with adverse health outcomes. This has been attributed, in part, to chronic stress. Telomere length (TL) has been used as a biomarker of chronic stress: TL is shorter in adults in a variety of contexts, including disadvantaged social standing and depression. We use data from 40, 9-y-old boys participating in the Fragile Families and Child Wellbeing Study to extend this observation to African American children. We report that exposure to disadvantaged environments is associated with reduced TL by age 9 y. We document significant associations between low income, low maternal education, unstable family structure, and harsh parenting and TL. These effects were moderated by genetic variants in serotonergic and dopaminergic pathways. Consistent with the differential susceptibility hypothesis, subjects with the highest genetic sensitivity scores had the shortest TL when exposed to disadvantaged social environments and the longest TL when exposed to advantaged environments. PMID:24711381

Laboratory studies on the vulnerability of young white sturgeon to predation

USGS Publications Warehouse

Gadomski, D.M.; Parsley, M.J.

2005-01-01

Despite evidence of annual spawning by white sturgeon Acipenser transmontanus in rivers of the northwestern United States and Canada, in some years and locations little or no recruitment of age-0 white sturgeon has been observed. We examined the vulnerability of white sturgeon larvae and juveniles to predation to further understand possible causes of mortality. We were particularly interested in the vulnerability of older larvae and juveniles because at about 25 mm total length (TL) white sturgeon develop sharp dorsal and lateral scutes that may act as a morphological defense. In the laboratory, white sturgeon ranging from newly hatched larvae to about 170-mm TL juveniles were exposed to predatory fishes they might encounter in the natural environment. We found that channel catfish Ictalurus punctatus (mean TL = 464 mm) and northern pikeminnow Ptychocheilus oregonensis (mean TL = 472 mm) ate white sturgeon up to mean sizes of 121 and 134 mm TL, respectively. Conversely, similarly sized walleyes Sander vitreus ingested almost no white sturgeon, although juvenile walleyes (mean TL = 184 mm) ate white sturgeon up to 59 mm TL. The smallest predator we tested, prickly sculpins Cottus asper (mean TL = 126 mm), ate white sturgeon up to a mean TL of 50 mm. Our study demonstrated that predation is a likely cause of mortality of age-0 white sturgeon and may be contributing to the year-class failures that have been observed. In addition, the results from this study could be used to reduce the predation risk of artificially propagated white sturgeon released to augment declining populations since fish could be reared to sizes where their vulnerability is low.

Smoking and perceived stress in relation to short salivary telomere length among caregivers of children with disabilities.

PubMed

Chen, Xiaoli; Velez, Juan Carlos; Barbosa, Clarita; Pepper, Micah; Andrade, Asterio; Stoner, Lee; De Vivo, Immaculata; Gelaye, Bizu; Williams, Michelle A

2015-01-01

Telomere length (TL), the length of repeated DNA sequence that forms protective caps at the end of chromosomes, has emerged as a novel biomarker of cell aging and oxidative stress. There is increasing research exploring the associations of smoking and perceived stress with TL, and the results are inconsistent. This study aimed to examine whether smoking and perceived stress were associated with shortened salivary TL among primary caregivers of children with disabilities. Using a quantitative polymerase chain reaction method, salivary TL was assessed among 89 caregivers aged 19-69 years (87% were women) who took care of disabled children in the Patagonia Region, Chile. Interviewer-administered questionnaires were used to collect information on sociodemographic and lifestyle factors. The 14-item Perceived Stress Scale was used to assess perceived stress. Mean relative TL was 0.92 (standard error = 0.03). Smokers had age-adjusted mean TL that was 0.07 units lower (β = -0.07, standard error = 0.03; p = 0.012) than non-smokers. Smokers were 2.17 times more likely to have shorter TL ( < 0.73, the lowest quartile of TL) than non-smokers (odds ratio = 3.17; 95% confidence interval = 1.05-9.52) with adjustment for age and perceived stress. Caregivers with higher perceived stress were 2.13 times more likely to have shorter TL (odds ratio = 3.13; 95% confidence interval = 1.03-9.55) than caregivers with lower perceived stress after adjustment for age and smoking. This study provides the first evidence of strong associations between smoking and perceived stress and shortened salivary TL among caregivers of children with disabilities. Larger studies with detailed information on smoking status are warranted to confirm our findings.

Smoking and perceived stress in relation to short salivary telomere length among caregivers of children with disabilities

PubMed Central

Chen, Xiaoli; Velez, Juan Carlos; Barbosa, Clarita; Pepper, Micah; Andrade, Asterio; Stoner, Lee; De Vivo, Immaculata; Gelaye, Bizu; Williams, Michelle A.

2014-01-01

Telomere length (TL), the length of repeated DNA sequence that forms protective caps at the end of chromosomes, has emerged as a novel biomarker of cell aging and oxidative stress. There is increasing research exploring the associations of smoking and perceived stress with TL, and the results are inconsistent. This study aimed to examine whether smoking and perceived stress were associated with shortened salivary TL among primary caregivers of children with disabilities. Using a quantitative polymerase chain reaction method, salivary TL was assessed among 89 caregivers aged 19–69 years (87% were women) who took care of disabled children in the Patagonia Region, Chile. Interviewer-administered questionnaires were used to collect information on sociodemographic and lifestyle behaviors. The 14-item Perceived Stress Scale was used to assess perceived stress. Mean relative TL was 0.92 (standard error=0.03). Smokers had age-adjusted mean TL that was 0.07 units lower (beta=−0.07, standard error=0.03; p=0.012) than non-smokers. Smokers were 2.17 times more likely to have shorter TL (<0.73, the lowest quartile of TL) than non-smokers (odds ratio =3.17; 95% confidence interval=1.05–9.52) with adjustment for age and perceived stress. Caregivers with higher perceived stress were 2.13 times more likely to have shorter TL (odds ratio=3.13; 95% confidence interval=1.03–9.55) than caregivers with lower perceived stress after adjustment for age and smoking. This study provides the first evidence of strong associations between smoking and perceived stress and shortened salivary TL among caregivers of children with disabilities. Larger studies with detailed information on smoking status are warranted to confirm our findings. PMID:25256607

Leukocyte Telomere Length in the Finnish Diabetes Prevention Study

PubMed Central

Hovatta, Iiris; de Mello, Vanessa D. F.; Kananen, Laura; Lindström, Jaana; Eriksson, Johan G.; Ilanne-Parikka, Pirjo; Keinänen-Kiukaanniemi, Sirkka; Peltonen, Markku; Tuomilehto, Jaakko; Uusitupa, Matti

2012-01-01

Leukocyte telomere length (TL) is considered a biomarker for biological aging. Shortened TL has been observed in many complex diseases, including type 2 diabetes (T2DM). Lifestyle intervention studies, e.g. the Diabetes Prevention Study (DPS), have shown a decrease in the incidence of T2DM by promoting healthy lifestyles in individuals with impaired glucose tolerance (IGT). Our aim was to study in the DPS the influence of the lifestyle intervention on TL. TL was measured by quantitative PCR-based method at two time points (N = 334 and 343) on average 4.5 years apart during the active intervention and post-intervention follow-up. TL inversely correlated with age. Our main finding was that TL increased in about two thirds of the individuals both in the intervention and in the control groups during follow-up; TL increased most in individuals with the shortest TL at the first measurement. TL was not associated with development of T2DM, nor did lifestyle intervention have an effect on TL. No association between insulin secretion or insulin resistance indices and TL was observed. We did not detect an association between TL and development of T2DM in the DPS participants. It could be due to all participants being overweight and having IGT at baseline, both of which have been found to be independently associated with shorter leukocyte TL in some earlier studies. TL had no substantial role in worsening of glucose tolerance in people with IGT. Our study confirms that leukocyte TL can increase with time even in obese people with impaired glucose metabolism. PMID:22493726

Allometric relationships among body mass, MUZZLE-tail length, and tibia length during the growth of Wistar rats.

PubMed

Santiago, Hildemberg Agostinho Rocha de; De Pierro, Lucas Rodolfo; Reis, Rafael Menezes; Caluz, Antônio Gabriel Ricardo Engracia; Ribeiro, Victor Barbosa; Volpon, José Batista

2015-11-01

To investigate allometric relationships among body mass (BM), muzzle-tail length (MTL), and tibia length (TL) in Wistar rats and establish their growth rate change parameters. Eighteen male and 18 female Wistar rats were studied from the 3rd to the 21st week of age. BM, MTL, and TL were measured daily, and relative growth was compared using allometry. A positive correlation between BM and MTL (p<0.05) and BM and TL (p<0.05) was observed. Males and females showed comparable curves; however, females had turning points at a younger age. The allometric relationship between BM and MTL presented a regular increase until reaching a mass of 351 g (males) and 405 g (females). BM and TL showed an initial increase until 185 g (males) and 182 g (females), and then reached a plateau that finished at 412 g (males) and 334 g (females), to display another increase. The allometric relationship of body mass with animal length and tibia length was comparable for male and female rats, with female rats maturing earlier. Animal longitudinal growth occurred in a single stage. In contrast, tibia length depicted two stages of accelerated growth with an intermediate period of deceleration.

Effects of Including Misidentified Sharks in Life History Analyses: A Case Study on the Grey Reef Shark Carcharhinus amblyrhynchos from Papua New Guinea

PubMed Central

Smart, Jonathan J.; Chin, Andrew; Baje, Leontine; Green, Madeline E.; Appleyard, Sharon A.; Tobin, Andrew J.; Simpfendorfer, Colin A.; White, William T.

2016-01-01

Fisheries observer programs are used around the world to collect crucial information and samples that inform fisheries management. However, observer error may misidentify similar-looking shark species. This raises questions about the level of error that species misidentifications could introduce to estimates of species’ life history parameters. This study addressed these questions using the Grey Reef Shark Carcharhinus amblyrhynchos as a case study. Observer misidentification rates were quantified by validating species identifications using diagnostic photographs taken on board supplemented with DNA barcoding. Length-at-age and maturity ogive analyses were then estimated and compared with and without the misidentified individuals. Vertebrae were retained from a total of 155 sharks identified by observers as C. amblyrhynchos. However, 22 (14%) of these were sharks were misidentified by the observers and were subsequently re-identified based on photographs and/or DNA barcoding. Of the 22 individuals misidentified as C. amblyrhynchos, 16 (73%) were detected using photographs and a further 6 via genetic validation. If misidentified individuals had been included, substantial error would have been introduced to both the length-at-age and the maturity estimates. Thus validating the species identification, increased the accuracy of estimated life history parameters for C. amblyrhynchos. From the corrected sample a multi-model inference approach was used to estimate growth for C. amblyrhynchos using three candidate models. The model averaged length-at-age parameters for C. amblyrhynchos with the sexes combined were  L¯∞ = 159 cm TL and  L¯0 = 72 cm TL. Females mature at a greater length (l50 = 136 cm TL) and older age (A50 = 9.1 years) than males (l50 = 123 cm TL; A50 = 5.9 years). The inclusion of techniques to reduce misidentification in observer programs will improve the results of life history studies and ultimately improve management through the use of more accurate data for assessments. PMID:27058734

Effects of Including Misidentified Sharks in Life History Analyses: A Case Study on the Grey Reef Shark Carcharhinus amblyrhynchos from Papua New Guinea.

PubMed

Smart, Jonathan J; Chin, Andrew; Baje, Leontine; Green, Madeline E; Appleyard, Sharon A; Tobin, Andrew J; Simpfendorfer, Colin A; White, William T

2016-01-01

Fisheries observer programs are used around the world to collect crucial information and samples that inform fisheries management. However, observer error may misidentify similar-looking shark species. This raises questions about the level of error that species misidentifications could introduce to estimates of species' life history parameters. This study addressed these questions using the Grey Reef Shark Carcharhinus amblyrhynchos as a case study. Observer misidentification rates were quantified by validating species identifications using diagnostic photographs taken on board supplemented with DNA barcoding. Length-at-age and maturity ogive analyses were then estimated and compared with and without the misidentified individuals. Vertebrae were retained from a total of 155 sharks identified by observers as C. amblyrhynchos. However, 22 (14%) of these were sharks were misidentified by the observers and were subsequently re-identified based on photographs and/or DNA barcoding. Of the 22 individuals misidentified as C. amblyrhynchos, 16 (73%) were detected using photographs and a further 6 via genetic validation. If misidentified individuals had been included, substantial error would have been introduced to both the length-at-age and the maturity estimates. Thus validating the species identification, increased the accuracy of estimated life history parameters for C. amblyrhynchos. From the corrected sample a multi-model inference approach was used to estimate growth for C. amblyrhynchos using three candidate models. The model averaged length-at-age parameters for C. amblyrhynchos with the sexes combined were L∞ = 159 cm TL and L0 = 72 cm TL. Females mature at a greater length (l50 = 136 cm TL) and older age (A50 = 9.1 years) than males (l50 = 123 cm TL; A50 = 5.9 years). The inclusion of techniques to reduce misidentification in observer programs will improve the results of life history studies and ultimately improve management through the use of more accurate data for assessments.

Low pH affects survival, growth, size distribution, and carapace quality of the postlarvae and early juveniles of the freshwater prawn Macrobrachium rosenbergii de Man

NASA Astrophysics Data System (ADS)

Kawamura, Gunzo; Bagarinao, Teodora; Yong, Annita Seok Kian; Chen, Chiau Yu; Noor, Siti Norasidah Mat; Lim, Leong Seng

2015-06-01

Acidification of rain water caused by air pollutants is now recognized as a serious threat to aquatic ecosystems. We examined the effects of low pH (control pH 7.5, pH 6, pH 5, pH 4) on the survival, growth, and shell quality of Macrobrachium rosenbergii postlarvae and early juveniles in the laboratory. Hatcheryproduced postlarvae (PL 5) were stocked at 250 PL per aquarium, acclimated over 7 d to experimental pH adjusted with hydrochloric acid, and reared for 30 d. Dead specimens were removed and counted twice a day. After 27 d rearing, all specimens were measured for total length and body weight. Carapace quality was assessed by spectrophotometry. Survival of juveniles was highest at pH 6 (binomial 95% confidence interval 79 - 89%) followed by control pH 7.5 (56 - 68%) and pH 5 (50 - 60%) and was lowest for unmetamorphosed postlarvae and juveniles at pH 4 (43 - 49%). The final median total length and body weight of juveniles were similar at control pH 7.5 (18.2 TL, 50.2 mg BW) and pH 6 (17.7 mm TL, 45.0 mg BW) but significantly less at pH 5 (16.7 mm TL, 38.2 mg BW); at pH 4, the postlarvae did not metamorphose and measured only 9.8 mm TL, 29.3 mg BW. Length frequency distribution showed homogeneous growth at pH 6, positive skew at control pH 7.5 and pH 5, and extreme heterogeneity at pH 4. The carapace showed different transmittance spectra and lower total transmittance (i.e. thicker carapace) in juveniles at pH 7.5, pH 6, and pH 5 than in unmetamorphosed postlarvae and juveniles with thinner carapace at pH 4. Thus, survival, growth, size distribution, and carapace quality of M. rosenbergii postlarvae and early juveniles were negatively affected by pH 5 and especially pH 4. The thinner carapace of the survivors at pH 4 was mostly due to their small size and failure to metamorphose. Natural waters affected by acid rain could decimate M. rosenbergii populations in the wild.

Dynamics of an introduced and unexploited Lake Whitefish population in Lake Pend Oreille, Idaho

USGS Publications Warehouse

Hosack, Michael A.; Hansen, Michael J.; Horner, Ned J.

2014-01-01

To evaluate biological potential of a commercial fishery for an unexploited Lake Whitefish Coregonus clupeaformis population in Lake Pend Oreille, Idaho, we estimated population parameters related to production and yield. The length frequency based on trap-netting in autumn 2005 was normal with a mean of 448 mm TL, whereas the length frequency based on gillnetting in spring 2006 was bimodal with a mean of 390 mm TL. Sex composition was skewed toward females (0.66) during autumn trap-netting. Shape parameters β of weight–length models for females (β = 3.38) and males (β = 3.45) were similar to those of other unexploited populations. Instantaneous growth rates K for females (K = 0.144 per year) and males (K = 0.153 per year) were among the lowest for unexploited populations across the species’ range. Age at 50% maturity (females: 6.5 years; males: 6.0 years) and length at 50% maturity (females: 390 mm TL; males: 378 mm TL) were high for unexploited populations. The natural mortality rate M (0.149 per year, ages 11–36) was among the lowest observed for unexploited populations. Adult population density was lower than that of other populations based on total surface area (mean = 1.35 fish/ha; 95% confidence interval [CI] = 1.11–1.78 fish/ha) but was average based on lake area shallower than 70 m (4.07 fish/ha; 95% CI = 3.35–5.35 fish/ha). Population density of juveniles and adults averaged 84 fish/ha (95% CI = 52–143 fish/ha) over the entire surface area and 278 fish/ha (95% CI = 173–474 fish/ha) over depths shallower than 70 m. The difference between the low M of the unexploited population in Lake Pend Oreille (M = 0.149 per year; annual mortality rate A = 14%) and the high sustainable total mortality Z of exploited stocks in the Laurentian Great Lakes (Z = 1.204; A = 70%) suggests a large scope for sustainable fishing mortality F (1.055 per year; exploitation rate u = 61%) that is equivalent to a sustainable Lake Whitefish harvest of 55,000 individuals (50,000–60,000 individuals) and 49,000 kg (45,000–54,000 kg) from Lake Pend Oreille.

Leucocytes telomere length and breast cancer risk/ susceptibility: A case-control study.

PubMed

Pavanello, Sofia; Varesco, Liliana; Gismondi, Viviana; Bruzzi, Paolo; Bolognesi, Claudia

2018-01-01

Telomere length in peripheral blood leukocytes (PBL-TL) was proposed as a biomarker of cancer risk. Recent scientific evidence suggested PBL-TL plays a diverse role in different cancers. Inconsistent results were obtained on PBL-TL in relation to breast cancer risk and specifically to the presence of BRCA1 and BRCA2 mutations. The aim of the present case-control study was to analyse the correlation between family history of breast cancer or presence of a BRCA mutation and PBL-TL in the hypothesis that TL is a modifier of cancer risk. PBL-TL was measured using the real-time quantitative PCR method in DNA for 142 cases and 239 controls. All the women enrolled were characterized for cancer family history. A subgroup of 48 women were classified for the presence of a BRCA mutation. PBL-TL were summarized as means and standard deviations, and compared by standard analysis of variance. A multivariable Generalised Linear Model was fitted to the data with PBL-TL as the dependent variable, case/control status and presence of a BRCA/VUS mutation as factors, and age in 4 strata as a covariate. Age was significantly associated with decreasing PBL-TL in controls (p = 0.01), but not in BC cases. The telomere length is shorter in cases than in controls after adjusting for age. No effect on PBL-TL of BMI, smoke nor of the most common risk factors for breast cancer was observed. No association between PBL-TL and family history was detected both in BC cases and controls. In the multivariate model, no association was observed between BRCA mutation and decreased PBL-TL. A statistically significant interaction (p = 0.031) between case-control status and a BRCA-mutation/VUS was observed, but no effect was detected for the interaction of cancer status and BRCA or VUS. Our study fails to provide support to the hypothesis that PBL-TL is associated with the risk of hereditary BC, or that is a marker of inherited mutations in BRCA genes.

Leucocytes telomere length and breast cancer risk/ susceptibility: A case-control study

PubMed Central

Pavanello, Sofia; Varesco, Liliana; Gismondi, Viviana; Bruzzi, Paolo

2018-01-01

Background Telomere length in peripheral blood leukocytes (PBL-TL) was proposed as a biomarker of cancer risk. Recent scientific evidence suggested PBL-TL plays a diverse role in different cancers. Inconsistent results were obtained on PBL-TL in relation to breast cancer risk and specifically to the presence of BRCA1 and BRCA2 mutations. The aim of the present case-control study was to analyse the correlation between family history of breast cancer or presence of a BRCA mutation and PBL-TL in the hypothesis that TL is a modifier of cancer risk. Methods PBL-TL was measured using the real-time quantitative PCR method in DNA for 142 cases and 239 controls. All the women enrolled were characterized for cancer family history. A subgroup of 48 women were classified for the presence of a BRCA mutation. PBL-TL were summarized as means and standard deviations, and compared by standard analysis of variance. A multivariable Generalised Linear Model was fitted to the data with PBL-TL as the dependent variable, case/control status and presence of a BRCA/VUS mutation as factors, and age in 4 strata as a covariate. Results Age was significantly associated with decreasing PBL-TL in controls (p = 0.01), but not in BC cases. The telomere length is shorter in cases than in controls after adjusting for age. No effect on PBL-TL of BMI, smoke nor of the most common risk factors for breast cancer was observed. No association between PBL-TL and family history was detected both in BC cases and controls. In the multivariate model, no association was observed between BRCA mutation and decreased PBL-TL. A statistically significant interaction (p = 0.031) between case-control status and a BRCA-mutation/VUS was observed, but no effect was detected for the interaction of cancer status and BRCA or VUS. Conclusion Our study fails to provide support to the hypothesis that PBL-TL is associated with the risk of hereditary BC, or that is a marker of inherited mutations in BRCA genes. PMID:29782524

Placental telomere length decreases with gestational age and is influenced by parity: a study of third trimester live-born twins.

PubMed

Gielen, M; Hageman, G; Pachen, D; Derom, C; Vlietinck, R; Zeegers, M P

2014-10-01

In contrast to the postnatal period, little is known about telomere length (TL) during prenatal life. The decrease in placental TL remains unknown, although intra uterine growth retardation and preeclampsia are associated with shorter placental TL. The aim of this study is to assess the decrease of placental TL during the third trimester of gestation and to explore the role of potential "growth influencing factors". The study sample consisted of 329 live-born twins from the East Flanders Prospective Twin Survey. TL was determined using a multiplex quantitative PCR method. Gestational age, sex, birth order, placental characteristics, parity, maternal and paternal age, diabetes, hypertension, smoking, alcohol use, and socio economic status (SES) were considered "growth influencing factors". Bivariable multilevel regression analysis with "growth influencing factors" was performed. Placental TL ranged from 4.3 kbp to 84.4 kbp with a median of 10.8 kbp. Ln(TL) decreased in a linear fashion with an estimated TL decreasing from 13.98 kbp at 28 weeks to 10.56 kbp at 42 weeks. The regression coefficient of gestational age became smaller if considered together with SES (b = -0.017; p = 0.08) or diabetes (b = -0.018; p = 0.07) and bigger if considered together with parity (b = -0.022; p = 0.02), indicating that part of the association between gestational age and telomere length is explained by these three confounding factors. Placental TL decreases during the third trimester of gestation of live-born twins with approximately 25% indicating that telomere shortening may play a role in aging of the placenta. Copyright © 2014 Elsevier Ltd. All rights reserved.

Telomere Length, Proviral Load and Neurologic Impairment in HTLV-1 and HTLV-2-Infected Subjects.

PubMed

Usadi, Benjamin; Bruhn, Roberta; Lin, Jue; Lee, Tzong-Hae; Blackburn, Elizabeth; Murphy, Edward L

2016-08-11

Short or damaged telomeres have been implicated in degenerative conditions. We hypothesized that analysis of telomere length (TL) in human T-cell lymphotropic virus (HTLV) infection and HTLV-associated neuropathy might provide clues to the etiology of HTLV-associated disease and viral dynamics. A subset of 45 human T-cell lymphotropic virus type 1 (HTLV-1), 45 human T-cell lymphotropic virus type 2 (HTLV-2), and 45 seronegative subjects was selected from the larger HTLV Outcomes Study (HOST) cohort, matched on age, sex and race/ethnicity. Telomere-to-single-copy gene (T/S) ratio (a measure of TL) and HTLV-1 and HTLV-2 proviral loads were measured in peripheral blood mononuclear cells (PBMCs) using quantitative PCR (qPCR). Vibration sensation measured by tuning fork during neurologic examinations performed as part of the HOST study allowed for an assessment of peripheral neuropathy. TL was compared between groups using t-tests, linear and logistic regression. Mean T/S ratio was 1.02 ± 0.16 in HTLV-1, 1.03 ± 0.17 in HTLV-2 and 0.99 ± 0.18 in HTLV seronegative subjects (p = 0.322). TL was not associated with HTLV-1 or -2 proviral load. Shorter TL was significantly associated with impaired vibration sense in the HTLV-2 positive group only. Overall, we found no evidence that telomere length was affected by chronic HTLV-1 and HTLV-2 infection. That TL was only associated with peripheral neuropathy in the HTLV-2-positive group is intriguing, but should be interpreted cautiously. Studies with larger sample size and telomere length measurement in lymphocyte subsets may clarify the relationship between TL and HTLV-infection.

Test anxiety and telomere length: Academic stress in adolescents may not cause rapid telomere erosion.

PubMed

Zou, Yaru; Leong, Waiian; Yao, Mingling; Hu, Xuefei; Lu, Sixiao; Zhu, Xiaowei; Chen, Lianxiang; Tong, Jianjing; Shi, Jingyi; Gilson, Eric; Ye, Jing; Lu, Yiming

2017-02-14

Academic stress (AS) is one of the most important health problems experienced by students, but no biomarker of the potential psychological or physical problems associated with AS has yet been identified. As several cross-sectional studies have shown that psychiatric conditions accelerate aging and shorten telomere length (TL), we explored whether AS affected TL.Between June 2014 and July 2014, we recruited 200 junior high school students with imminent final examinations for participation in this study. The students were divided into three subgroups (mild, moderate, and severe anxiety) using the Sarason Test Anxiety Scale (TAS). Saliva samples were collected for TL measurement via quantitative polymerase chain reaction (qPCR).Students from both a specialized and a general school suffered from anxiety (p > 0.05). A total 35% had severe anxiety (score: 26.09±3.87), 33% had moderate anxiety (16.98±2.64), and 32% had mild anxiety (7.89±1.92). The TAS values differed significantly (p < 0.05) among the three subgroups, but the TLs of saliva cells differed only slightly (p > 0.05): 1.14±0.46 for those with severe anxiety, 1.02±0.40 for those with moderate anxiety, and 1.12±0.45 for those with mild anxiety.Previous reports have found that AS is very common in Asian adolescents. We found no immediate telomere shortening in adolescents with AS. Longitudinal observations are required to determine if TL is affected by AS.

The use of telomere length as a predictive biomarker for injury prognosis in juvenile rats following a concussion/mild traumatic brain injury.

PubMed

Hehar, Harleen; Mychasiuk, Richelle

2016-03-01

Telomeres were originally believed to be passive players in cellular replication, but recent research has highlighted their more active role in epigenetic patterning and promotion of cellular growth and survival. Furthermore, literature demonstrates that telomere length (TL) is responsive to environmental manipulations such as prenatal stress and dietary programming. As the search for a prognostic biomarker of concussion has had limited success, this study sought to examine whether or not telomere length (TL) could be an efficacious predictor of symptom severity in juvenile rats following concussion. Rats from four distinct experimental groups (caloric restriction (CR), high fat diet (HFD), exercise (EX), and standard controls (STD)) received a mild traumatic brain injury (mTBI)/concussion and were then subjected to a behavioural test battery. The test battery was scored and the animals were categorized as poor, average, or good, based on their performance on the 6 tests examined. Skin cells (from ear notch samples) were taken 17days post-injury and DNA was extracted for telomere length analysis. Ear notch skin cell TL was highly correlated with brain tissue TL for a given individual. Animals in the CR and EX cohorts had significantly longer telomeres, while animals in the HFD cohort had significantly shorter telomeres, when compared to controls. The mTBI/concussion reduced TL in all cohorts except the EX group. A significant linear relationship was found between TL and performance on the behavioural test battery, whereby shorter telomeres were associated with poorer performance and longer telomeres with better performance. As performance on the test battery is linked to symptom severity, this study found TL to be a reasonable tool for concussion prognosis. Future studies with human populations should examine the validity of TL in peripheral cells, as a predictor of concussion pathology. Copyright © 2015 Elsevier Inc. All rights reserved.

Relationship between fish size and upper thermal tolerance

USGS Publications Warehouse

Recsetar, Matthew S.; Zeigler, Matthew P.; Ward, David L.; Bonar, Scott A.; Caldwell, Colleen A.

2012-01-01

Using critical thermal maximum (CTMax) tests, we examined the relationship between upper temperature tolerances and fish size (fry-adult or subadult lengths) of rainbow trout Oncorhynchus mykiss (41-200-mm TL), Apache trout O. gilae apache (40-220-mm TL), largemouth bass Micropterus salmoides (72-266-mm TL), Nile tilapia Oreochromis niloticus (35-206-mm TL), channel catfish Ictalurus punctatus (62-264 mm-TL), and Rio Grande cutthroat trout O. clarkii virginalis (36-181-mm TL). Rainbow trout and Apache trout were acclimated at 18°C, Rio Grande cutthroat trout were acclimated at 14°C, and Nile tilapia, largemouth bass, and channel catfish were acclimated at 25°C, all for 14 d. Critical thermal maximum temperatures were estimated and data were analyzed using simple linear regression. There was no significant relationship (P > 0.05) between thermal tolerance and length for Nile tilapia (P = 0.33), channel catfish (P = 0.55), rainbow trout (P = 0.76), or largemouth bass (P = 0.93) for the length ranges we tested. There was a significant negative relationship between thermal tolerance and length for Rio Grande cutthroat trout (R2 = 0.412, P 2 = 0.1374, P = 0.028); however, the difference was less than 1°C across all lengths of Apache trout tested and about 1.3°C across all lengths of Rio Grande cutthroat trout tested. Because there was either no or at most a slight relationship between upper thermal tolerance and size, management and research decisions based on upper thermal tolerance should be similar for the range of sizes within each species we tested. However, the different sizes we tested only encompassed life stages ranging from fry to adult/subadult, so thermal tolerance of eggs, alevins, and larger adults should also be considered before making management decisions affecting an entire species.

Influences of body size and environmental factors on autumn downstream migration of bull trout in the Boise River, Idaho

Treesearch

Lauri Monnot; Jason B. Dunham; Tammy Hoem; Peter Koetsier

2008-01-01

Many fishes migrate extensively through stream networks, yet patterns are commonly described only in terms of the origin and destination of migration (e.g., between natal and feeding habitats). To better understand patterns of migration in bull trout, Salvelinus confluentus we studied the influences of body size (total length [TL]) and environmental...

Risky family processes prospectively forecast shorter telomere length mediated through negative emotions.

PubMed

Brody, Gene H; Yu, Tianyi; Shalev, Idan

2017-05-01

This study was designed to examine prospective associations of risky family environments with subsequent levels of negative emotions and peripheral blood mononuclear cell telomere length (TL), a marker of cellular aging. A second purpose was to determine whether negative emotions mediate the hypothesized link between risky family processes and diminished telomere length. Participants were 293 adolescents (age 17 years at the first assessment) and their primary caregivers. Caregivers provided data on risky family processes when the youths were age 17 years, youths reported their negative emotions at age 18 years, and youths' TL was assayed from a blood sample at age 22 years. The results revealed that (a) risky family processes forecast heightened negative emotions (β = .316, p < .001) and diminished TL (β = -.199, p = .003) among youths, (b) higher levels of negative emotions forecast shorter TL (β = -.187, p = .012), and (c) negative emotions served as a mediator connecting risky family processes with diminished TL (indirect effect = -0.012, 95% CI [-0.036, -0.002]). These findings are consistent with the hypothesis that risky family processes presage premature cellular aging through effects on negative emotions, with potential implications for lifelong health. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Radiation loss of planar surface plasmon polaritons transmission lines at microwave frequencies.

PubMed

Xu, Zhixia; Li, Shunli; Yin, Xiaoxing; Zhao, Hongxin; Liu, Leilei

2017-07-21

Radiation loss of a typical spoof surface plasmon polaritons (SSPPs) transmission line (TL) is investigated in this paper. A 325 mm-long SSPPs TL is designed and fabricated. Simulated results show that radiation loss contributes more to transmission loss than dielectric loss and conductor loss from 2 GHz to 10 GHz. Radiation loss of the SSPPs TL could be divided into two parts, one is caused by the input mode converter, and the other is caused by the corrugated metallic strip. This paper explains mechanisms of radiation loss from different parts, designs a loaded SSPPs TL with a series of resistors to absorb electromagnetic energy on corrugated metallic strip, and then discriminates radiation loss from the input mode converter, proposes the concept of average radiation length (ARL) to evaluate radiation loss from SSPPs of finite length, and concludes that radiation loss is mainly caused by corrugated structure of finite length at low frequency band and by the input mode converter at high frequency band. To suppress radiation loss, a mixed slow wave TL based on the combination of coplanar waveguides (CPWs) and SSPPs is presented. The designed structure, sample fabrication and experimental verification are discussed.

Risky Family Processes Prospectively Forecast Shorter Telomere Length Mediated through Negative Emotions

PubMed Central

Brody, Gene H.; Yu, Tianyi; Shalev, Idan

2016-01-01

Objective This study was designed to examine prospective associations of risky family environments with subsequent levels of negative emotions and peripheral blood mononuclear cell telomere length (TL), a marker of cellular aging. A second purpose was to determine whether negative emotions mediate the hypothesized link between risky family processes and diminished telomere length. Methods Participants were 293 adolescents (age 17 years at the first assessment) and their primary caregivers. Caregivers provided data on risky family processes when the youths were age 17 years, youths reported their negative emotions at age 18 years, and youths’ TL was assayed from a blood sample at age 22 years. Results The results revealed that (a) risky family processes forecast heightened negative emotions (β = .316, p < .001) and diminished TL (β = −.199, p = .003) among youths, (b) higher levels of negative emotions forecast shorter TL (β = −.187, p = .012), and (c) negative emotions served as a mediator connecting risky family processes with diminished TL (indirect effect = −0.012, 95% CI [−0.036, −0.002]). Conclusions These findings are consistent with the hypothesis that risky family processes presage premature cellular aging through effects on negative emotions, with potential implications for lifelong health. PMID:27831704

History of child maltreatment and telomere length in immune cell subsets: Associations with stress- and attachment-related hormones.

PubMed

Boeck, Christina; Krause, Sabrina; Karabatsiakis, Alexander; Schury, Katharina; Gündel, Harald; Waller, Christiane; Kolassa, Iris-Tatjana

2018-05-01

Experiencing maltreatment during childhood can have long-lasting consequences for both mental and physical health. Immune cell telomere length (TL) shortening might be one link between child maltreatment (CM) experiences and adverse health outcomes later in life. While the stress hormone cortisol has been associated with TL attrition, the attachment-related hormone oxytocin may promote resilience. In 15 mothers with and 15 age- and body mass index-matched mothers without CM, we assessed TL in peripheral blood mononuclear cells and selected immune cell subsets (monocytes, naive, and memory cytotoxic T cells) by quantitative fluorescence in situ hybridization, as well as peripheral cortisol and oxytocin levels. Memory cytotoxic T cells showed significantly shorter TL in association with CM, whereas TL in monocytes and naive cytotoxic T cells did not significantly differ between the two groups. Across both groups, cortisol was negatively associated with TL, while oxytocin was positively associated with TL in memory cytotoxic T cells. These results indicate that long-lived memory cytotoxic T cells are most affected by the increased biological stress state associated with CM. Keeping in mind the correlational and preliminary nature of the results, the data suggest that cortisol may have a damaging and oxytocin a protective function on TL.

Longer Telomere Length in Elite Master Sprinters: Relationship to Performance and Body Composition.

PubMed

Simoes, Herbert Gustavo; Sousa, Caio Victor; Dos Santos Rosa, Thiago; da Silva Aguiar, Samuel; Deus, Lysleine Alves; Rosa, Erica Carine Campos Caldas; Amato, Angelica Amorim; Andrade, Rosangela Vieira

2017-12-01

Emergent evidence suggests that the long-term healthy lifestyle of master athletes may attenuate aging. We compared telomere length (TL) of high-level master sprinters and non-athlete age-matched controls, and analyzed the relationships of TL with performance and body fat. Elite master sprinters (n=11; aged 50.1±9.2yrs) and healthy untrained controls (n=10; aged 45.4±10.9yrs) had blood samples collected for biochemical and biomolecular analyses. Master sprinters had longer TL, lower body fat and BMI, and a better lipid profile than age-matched controls (p<0.05). A large effect size was verified comparing TL between athletes vs. controls (Cohen's d=1.039), with a significant negative correlation between TL and performance decline per decade (r=-0.624, p<0.01) and a positive correlation of TL and actual performance level (r=0.641, p<0.01). In conclusion, TL of elite master sprinters was longer than their untrained peers, and seems to be not only a marker of health status, but also an indicator of sports longevity since both actual performance level and its decrease over years were related to TL. Further research might assess the TL of elite master endurance athletes for comparison with sprinters, and also investigate the underlying mechanisms by which the attenuation of telomere shortening occurs in master athletes. © Georg Thieme Verlag KG Stuttgart · New York.

Setting the trajectory: racial disparities in newborn telomere length.

PubMed

Drury, Stacy S; Esteves, Kyle; Hatch, Virginia; Woodbury, Margaret; Borne, Sophie; Adamski, Alys; Theall, Katherine P

2015-05-01

To explore racial differences in newborn telomere length (TL) and the effect moderation of the sex of the infant while establishing the methodology for the use of newborn blood spots for TL analyses. Pregnant mothers were recruited from the Greater New Orleans area. TL was determined via monochrome multiplex quantitative real-time polymerase chain reaction on DNA extracted from infant blood spots. Demographic data and other covariates were obtained via maternal report before the infant's birth. Birth outcome data were obtained from medical records and maternal report. Black infants weighed significantly less than white infants at birth and had significantly longer TL than white infants (P=.0134), with the strongest effect observed in black female infants. No significant differences in gestational age were present. Significant racial differences in TL were present at birth in this sample, even after we controlled for a range of birth outcomes and demographic factors. Because longer initial TL is predictive of more rapid TL attrition across the life course, these findings provide evidence that, even at birth, biological vulnerability to early life stress may differ by race and sex. Copyright © 2015 Elsevier Inc. All rights reserved.

Telomere length dynamics in human memory T cells specific for viruses causing acute or latent infections

PubMed Central

2013-01-01

Background Declining telomere length (TL) is associated with T cell senescence. While TL in naïve and memory T cells declines with increasing age, there is limited data on TL dynamics in virus-specific memory CD4+ T cells in healthy adults. We combined BrdU-labeling of virus-stimulated T cells followed with flow cytometry-fluorescent in situ hybridization for TL determination. We analyzed TL in T cells specific for several virus infections: non-recurring acute (vaccinia virus, VACV), recurring-acute (influenza A virus, IAV), and reactivating viruses (varicella-zoster virus, VZV, and cytomegalovirus, CMV) in 10 healthy subjects. Additionally, five subjects provided multiple blood samples separated by up to 10 years. Results VACV- and CMV-specific T cells had longer average TL than IAV-specific CD4+ T cells. Although most virus-specific cells were CD45RA-, we observed a minor population of BrdU+ CD45RA+ T cells characterized by long telomeres. Longitudinal analysis demonstrated a slow decline in average TL in virus-specific T cells. However, in one subject, VZV reactivation led to an increase in average TL in VZV-specific memory T cells, suggesting a conversion of longer TL cells from the naïve T cell repertoire. Conclusions TLs in memory CD4+ T cells in otherwise healthy adults are heterogeneous and follow distinct virus-specific kinetics. These findings suggests that the distribution of TL and the creation and maintenance of long TL memory T cells could be important for the persistence of long-lived T cell memory. PMID:23971624

Telomere length dynamics in human memory T cells specific for viruses causing acute or latent infections.

PubMed

O'Bryan, Joel M; Woda, Marcia; Co, Mary; Mathew, Anuja; Rothman, Alan L

2013-08-26

Declining telomere length (TL) is associated with T cell senescence. While TL in naïve and memory T cells declines with increasing age, there is limited data on TL dynamics in virus-specific memory CD4+ T cells in healthy adults. We combined BrdU-labeling of virus-stimulated T cells followed with flow cytometry-fluorescent in situ hybridization for TL determination. We analyzed TL in T cells specific for several virus infections: non-recurring acute (vaccinia virus, VACV), recurring-acute (influenza A virus, IAV), and reactivating viruses (varicella-zoster virus, VZV, and cytomegalovirus, CMV) in 10 healthy subjects. Additionally, five subjects provided multiple blood samples separated by up to 10 years. VACV- and CMV-specific T cells had longer average TL than IAV-specific CD4+ T cells. Although most virus-specific cells were CD45RA-, we observed a minor population of BrdU+ CD45RA+ T cells characterized by long telomeres. Longitudinal analysis demonstrated a slow decline in average TL in virus-specific T cells. However, in one subject, VZV reactivation led to an increase in average TL in VZV-specific memory T cells, suggesting a conversion of longer TL cells from the naïve T cell repertoire. TLs in memory CD4+ T cells in otherwise healthy adults are heterogeneous and follow distinct virus-specific kinetics. These findings suggests that the distribution of TL and the creation and maintenance of long TL memory T cells could be important for the persistence of long-lived T cell memory.

Baseline biopsychosocial determinants of telomere length and 6-year attrition rate.

PubMed

Révész, Dóra; Milaneschi, Yuri; Terpstra, Erik M; Penninx, Brenda W J H

2016-05-01

Short leukocyte telomere length (TL) and accelerated telomere attrition have been associated with various deleterious health outcomes, although their determinants have not been explored collectively in a large-scale study. Leukocyte TL was measured (baseline N=2936; 6-year follow-up N=1860) in participants (18-65 years) from the NESDA study. Baseline determinants of TL included sociodemographics, lifestyle, chronic diseases, psychosocial stressors, and metabolic and physiological stress markers. Multivariate linear regression models were used to examine the associations between these determinants and (1) baseline TL, and (2) 6-year TL change. Multinomial logistic regression analyses were used to examine the predictors of telomere attrition and lengthening, as compared to stable TL. Short baseline TL was associated with older age, male sex, non-European ethnicity, cigarette smoking, recent life events, and higher triglycerides, glucose and pre-ejection period (R(2)=11.3%). The 6-year telomere attrition was inversely associated with baseline TL (R(2)=51.6%); also older age, long sleep, not having a partner, high childhood trauma index, and gastrointestinal disease were associated with 6-year TL attrition (additional R(2)=3.7%). Telomere attrition seemed to have slightly more predictors than lengthening. Sociodemographic, lifestyle, psychosocial stress and metabolic and physiological stress factors are cross-sectionally linked with TL. Telomere attrition over six years was strongly associated with baseline TL, suggesting an internal homeostatic influence. Modulation of the identified determinants may become target of future studies to promote telomere maintenance and healthy aging. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reproductive development in the sicklefin chub in the Missouri and Lower Yellowstone Rivers

USGS Publications Warehouse

Dieterman, Douglas J.; Roberts, Eric; Braaten, Patrick J.; Galat, David L.

2006-01-01

We describe aspects of sicklefin chub (Macrhybopsis meeki) reproductive development from three study areas encompassing greater than 2,700 km of the Missouri and Lower Yellowstone rivers. The sicklefin chub was collected between late July and early October in 1996 and 1997. A total of 193 sicklefin chub was collected and examined for reproductive characteristics. Twenty-nine sicklefin chub were found to be reproductively mature females. Some sicklefin chub matured at age 2, but most matured at age 3 and all matured by age 4. Females first became mature at 70 to 79 mm total length (TL) in the Upper Missouri River reach in central Montana, 80 to 89 mm TL in the Missouri and Lower Yellowstone rivers in eastern Montana-western North Dakota, and 90 to 99 mm TL in the lower Missouri River in Nebraska, Iowa, Kansas, and Missouri. Gonad mass of gravid females averaged 6.9% of total body mass and ranged from 1.7 to 13.5%. Total number of oocytes per female, ranged from 7 to 1,561. Reproductive development of the sicklefin chub appeared to be group synchronous or synchronous indicating multiple spawnings during a spawning season. This variability in spawning mode required cautious interpretation of gonadosomatic index values and oocyte counts as estimates of total fecundity, because some females might have released a cohort of oocytes prior to their capture.

Longitudinal patterns in flathead catfish relative abundance and length at age within a large river: Effects of an urban gradient

USGS Publications Warehouse

Paukert, C.P.; Makinster, A.S.

2009-01-01

We investigated the spatial variation of flathead catfish (Pylodictis olivaris) relative abundance and growth in the 274 km long Kansas River to determine if population dynamics of catfish are related to urbanization. Electrofishing was conducted at 462 random sites throughout the river in summer, 2005-2006 to collect fish. Relative abundance of age 1 fish (???200mm), subadult (>200-400mm) and adult fish (>400 mm) ranged from 0.34 to 14.67 fish h-1, mean length at age 1 was 165 (range: 128-195) mm total length (TL) and mean length at age 3 was 376 mm TL (range: 293-419mm TL). The proportion of land use within 200 m of the river edge was between 0 and 0.54 urban. River reaches with high relative abundance of age 1 flathead catfish had high relative abundance of subadult and adult catfish. River reaches with fast flathead catfish growth to age 1 had fast growth to age 3. High urban land use and riprap in the riparian area were evident in river reaches near the heavily populated Kansas City and Topeka, Kansas, USA. Reaches with increased number of log jams and islands had decreased riparian agriculture. Areas of low urbanization had faster flathead catfish growth (r = 0.67, p = 0.005). Relative abundance of flathead catfish was higher in more agricultural areas (r = -0.57, p = 0.02). Changes in land use in riverine environments may alter population dynamics of a fish species within a river. Spatial differences in population dynamics need to be considered when evaluating riverine fish populations. Published in 2008 by John Wiley & Sons Ltd.

Gonadogenesis and Sex Differentiation in the Korean Rose Bitterling, Rhodeus uyekii)

PubMed Central

Goo, In Bon; Kim, Jung Eun; Kim, Myung Hun; Choi, Hye-Sung; Kong, Hee Jeong; Lee, Jeong Ho; Park, In-Seok

2016-01-01

ABSTRACT This report describes the sex differentiation of the Korean rose bitterling, Rhodeus uyekii, from hatching to 170 days post-hatch (DPH) in relation to total length (TL), body weight (BW), and integral water temperature (IWT). The growth curve of TL from just hatching to 83 DPH was 5.144e0.045t (R² = 0.961; t, time), and that of BW was 2.398e0.086t (R² = 0.725). Primordial germ cells (PGCs) were observed at 17 DPH (7.9 mm TL, 3.74 mg BW, 374°C IWT), and thereafter began to protrude into the peritoneal cavity. At 21 DPH (9.2±0.14 mm TL, 4.8±0.07 mg BW, 462°C IWT), some PGCs contained condensed chromatin and oocyte were observed in meiotic prophase. In contrast to the ovaries, which grew gradually after sexual differentiation, testes began multiplying at 25 DPH (10.1 mm TL, 5.42 mg BW, 550°C IWT), when testicular differentiation was first identified, and multiplied continuously thereafter. At 33 DPH (11.2 mm TL, 10.5 mg BW, 726°C IWT), the developing testes contained spermatogonia that exhibited mitotic activity. No spermatocyte or sperm cell was observed until 83 DPH (18.9 TL, 48.2 mg BW, 1,826°C IWT). At 170 DPH (32.5 mm TL, 270.1 mg BW, 3,740°C IWT), which was the end point of this study, the mature ovaries showed germinal vesicle breakdown, while the mature testes contained observable spermatocytes and sperm cells. These results allow us to identify the sex differentiation type of the Korean rose bitterling as differentiated gonochoristic. PMID:28144634

Gonadogenesis and Sex Differentiation in the Korean Rose Bitterling, Rhodeus uyekii).

PubMed

Goo, In Bon; Kim, Jung Eun; Kim, Myung Hun; Choi, Hye-Sung; Kong, Hee Jeong; Lee, Jeong Ho; Park, In-Seok

2016-12-01

This report describes the sex differentiation of the Korean rose bitterling, Rhodeus uyekii , from hatching to 170 days post-hatch (DPH) in relation to total length (TL), body weight (BW), and integral water temperature (IWT). The growth curve of TL from just hatching to 83 DPH was 5.144e 0.045t ( R ² = 0.961; t, time), and that of BW was 2.398e 0.086t ( R ² = 0.725). Primordial germ cells (PGCs) were observed at 17 DPH (7.9 mm TL, 3.74 mg BW, 374°C IWT), and thereafter began to protrude into the peritoneal cavity. At 21 DPH (9.2±0.14 mm TL, 4.8±0.07 mg BW, 462°C IWT), some PGCs contained condensed chromatin and oocyte were observed in meiotic prophase. In contrast to the ovaries, which grew gradually after sexual differentiation, testes began multiplying at 25 DPH (10.1 mm TL, 5.42 mg BW, 550°C IWT), when testicular differentiation was first identified, and multiplied continuously thereafter. At 33 DPH (11.2 mm TL, 10.5 mg BW, 726°C IWT), the developing testes contained spermatogonia that exhibited mitotic activity. No spermatocyte or sperm cell was observed until 83 DPH (18.9 TL, 48.2 mg BW, 1,826°C IWT). At 170 DPH (32.5 mm TL, 270.1 mg BW, 3,740°C IWT), which was the end point of this study, the mature ovaries showed germinal vesicle breakdown, while the mature testes contained observable spermatocytes and sperm cells. These results allow us to identify the sex differentiation type of the Korean rose bitterling as differentiated gonochoristic.

Physical Activity, Physical Fitness and Leukocyte Telomere Length: the Cardiovascular Health Study.

PubMed Central

Soares-Miranda, Luisa; Imamura, Fumiaki; Siscovick, David; Jenny, Nancy Swords; Fitzpatrick, Annette L; Mozaffarian, Dariush

2015-01-01

Introduction The influence of physical activity (PA) and physical fitness (PF) at older ages on changes in telomere length (TL), repetitive DNA sequences that may mark biologic aging, is not well-established. Few prior studies have been conducted in older adults, these were mainly cross-sectional, and few evaluated PF. Methods We investigated cross-sectional and prospective associations of PA and PF with leukocyte TL among 582 older adults (age 73±5 y at baseline) in the Cardiovascular Health Study, having serial TL measures and PA and PF assessed multiple times. Cross-sectional associations were assessed using multivariable repeated-measures regression, in which cumulatively averaged PA and PF measures were related to TL. Longitudinal analyses assessed cumulatively averaged PA and PF against later changes in TL; and changes in cumulatively averaged PA and PF against changes in TL. Results Cross-sectionally, greater walking distance and chair test performance, but not other PA and PF measures, were each associated with longer TL (p-trend=0.007, 0.04 respectively). In longitudinal analyses, no significant associations of baseline PA and PF with change in TL were observed. In contrast, changes in leisure-time activity and chair test performance were each inversely associated with changes in TL. Conclusions Cross-sectional analyses suggest that greater PA and PF are associated with longer TL. Prospective analyses show that changes in PA and PF are associated with differences in changes in TL. Even later in life, changes in certain PA and PF measures are associated with changes in TL, suggesting that leisure-time activity and fitness could reduce leukocyte telomere attrition among older adults. PMID:26083773

Diurnal and stress-reactive dehydroepiandrosterone levels and telomere length in youth

PubMed Central

Dismukes, Andrew R; Meyer, Vanessa J; Shirtcliff, Elizabeth A; Theall, Katherine P; Esteves, Kyle C

2016-01-01

The current investigation examined the association between the aging-related biomarkers dehydroepiandrosterone (DHEA) and telomere length (TL) in community-recruited African-American youth. The examination of DHEA included stress reactive, basal and diurnal sampling, in order to elucidate the underlying physiological process that may overlap with TL. One hundred and two participants completed the Trier Social Stressor Test for children (TSST-C). TL was obtained from all youth from buccal swabs on the same day as the TSST-C. Saliva samples from 83 participants were obtained over the course of two additional days to measure waking and diurnal levels of DHEA. DHEA diurnal slope was a robust predictor of TL (B=0.516, P<0.05), while other DHEA values were not significantly associated with TL. This study is one of the first studies to examine basal, diurnal and reactivity measurements of DHEA in youth. Furthermore, this is the first study, to our knowledge, to demonstrate a positive association between DHEA, a putative anti-aging hormone, and TL, an indicator of cellular aging. PMID:27221260

Diurnal and stress-reactive dehydroepiandrosterone levels and telomere length in youth.

PubMed

Dismukes, Andrew R; Meyer, Vanessa J; Shirtcliff, Elizabeth A; Theall, Katherine P; Esteves, Kyle C; Drury, Stacy S

2016-05-01

The current investigation examined the association between the aging-related biomarkers dehydroepiandrosterone (DHEA) and telomere length (TL) in community-recruited African-American youth. The examination of DHEA included stress reactive, basal and diurnal sampling, in order to elucidate the underlying physiological process that may overlap with TL. One hundred and two participants completed the Trier Social Stressor Test for children (TSST-C). TL was obtained from all youth from buccal swabs on the same day as the TSST-C. Saliva samples from 83 participants were obtained over the course of two additional days to measure waking and diurnal levels of DHEA. DHEA diurnal slope was a robust predictor of TL (B=0.516, P<0.05), while other DHEA values were not significantly associated with TL. This study is one of the first studies to examine basal, diurnal and reactivity measurements of DHEA in youth. Furthermore, this is the first study, to our knowledge, to demonstrate a positive association between DHEA, a putative anti-aging hormone, and TL, an indicator of cellular aging. © 2016 The authors.

Non-supportive Parenting Affects Telomere Length in Young Adulthood Among African Americans: Mediation through Substance Use

PubMed Central

Beach, Steven R. H.; Lei, Man Kit; Brody, Gene H.; Yu, Tianyi; Philibert, Robert A.

2015-01-01

Telomere length (TL) is an indicator of age related changes at the cellular level associated with heightened mortality risk. The effect of non-supportive parenting (NSP) during late adolescence and young adulthood on TL 5 years later was examined in a sample of N = 183 young adult African Americans to determine if effects of NSP on TL were mediated by substance use. Results indicated that the effect of caregiver reported NSP on diminished TL was mediated by escalation of drinking and smoking in young adulthood, even after controlling effects of socioeconomic status risk, gender, BMI, young adult stress, and intervention status. Results suggest that prevention of NSP may influence later physical health consequences by influencing substance use trajectory. PMID:25485673

Intratumoral diversity of telomere length in individual neuroblastoma tumors.

PubMed

Pezzolo, Annalisa; Pistorio, Angela; Gambini, Claudio; Haupt, Riccardo; Ferraro, Manuela; Erminio, Giovanni; De Bernardi, Bruno; Garaventa, Alberto; Pistoia, Vito

2015-04-10

The purpose of the work was to investigate telomere length (TL) and mechanisms involved in TL maintenance in individual neuroblastoma (NB) tumors. Primary NB tumors from 102 patients, ninety Italian and twelve Spanish, diagnosed from 2000 to 2008 were studied. TL was investigated by quantitative fluorescence in situ hybridization (IQ-FISH) that allows to analyze individual cells in paraffin-embedded tissues. Fluorescence intensity of chromosome 2 centromere was used as internal control to normalize TL values to ploidy. Human telomerase reverse transcriptase (hTERT) expression was detected by immunofluorescence in 99/102 NB specimens.The main findings are the following: 1) two intratumoral subpopulations of cancer cells displaying telomeres of different length were identified in 32/102 tumors belonging to all stages. 2) hTERT expression was detected in 99/102 tumors, of which 31 displayed high expression and 68 low expression. Alternative lengthening of telomeres (ALT)-mechanism was present in 60/102 tumors, 20 of which showed high hTERT expression. Neither ALT-mechanism nor hTERT expression correlated with heterogeneous TL. 3) High hTERT expression and ALT positivity were associated with significantly reduced Overall Survival. 4) High hTERT expression predicted relapse irrespective of patient age. Intratumoral diversity in TL represents a novel feature in NB.In conclusion, diversity of TL in individual NB tumors was strongly associated with disease progression and death, suggesting that these findings are of translational relevance. The combination of high hTERT expression and ALT positivity may represent a novel biomarker of poor prognosis that deserves further investigation.

Age, Growth and Reproduction of the Eastern Mudminnow (Umbra pygmaea) at the Great Swamp National Wildlife Refuge, New Jersey.

USGS Publications Warehouse

Panek, Frank; Weis, Judith S.

2012-01-01

Umbra pygmaea DeKay (Eastern Mudminnow) is one of four species of Umbridae in North America. There is little published life-history information on the species within its native range, particularly on age, growth, and reproduction. This study focuses on these aspects of the life history of this fish at the Great Swamp National Wildlife Refuge in Morris County, NJ. A total of 336 fish of seven species was collected from June 1978 through May 1979, with the Eastern Mudminnow comprising 74% of the total. The average annual growth increment in total length for the Eastern Mudminnow was 15.3 2.06 mm, with age-1 fish averaging 40 mm total length and age-5 fish, the oldest collected, averaging 107 mm total length. The length-weight relationship was log10W = -5.291 + 3.182 log10TL mm for males and log10W = -4.999 + 3.032 log10TL mm for females. We observed no statistically significant sexually dimorphic differences in length-weight relationships in this population. The ratio of females to males increased from a low of 0.6 (predominance of male fish) at age-1 to a high of 4.6 (predominance of females) at age-5. Annual mortality for age 2–5 fish ranged from 40–76% with a mean of 59 13%. Age-specific fecundity estimates ranged from 250 eggs/female at age-1 to 2168 eggs/female at age-5. The relationship of number of mature ova to age was best described by the exponential function y = 149.29e0.5287x, where y = age-specific fecundity and x = age in years. Ova ranged from 0.1–0.2 mm in diameter in June and July and averaged 1.41 0.1 mm (range = 1.29–1.62 mm) in early February prior to spawning. Peak spawning occurred in mid-April at temperatures of 9–12 °C, and all females were spent by late April (13–15 °C).

Telomere length is severely and similarly reduced in JAK2V617F-positive and -negative myeloproliferative neoplasms

PubMed Central

Bernard, L; Belisle, C; Mollica, L; Provost, S; Roy, D-C; Gilliland, DG; Levine, RL; Busque, L

2015-01-01

Myeloproliferative neoplasms (MPNs) are clonal stem cell disorders characterized by chronic proliferation of hematopoietic progenitors. We studied the telomere length (TL) of 335 MPN patients and 93 gender- and age-matched controls using a quantitative PCR method (relative TL calculated as the ratio of the amount of telomere DNA vs single-copy DNA: T/S ratio). TL was markedly reduced in MPN patients compared with controls (T/S 0.561 vs 0.990, P<0.001). In JAK2V617F MPN patients, TL correlated inversely with allelic burden (P<0.001). Patients homozygous for the mutation (allelic burden 90–100%) had the shortest TL, even when compared with patients with lower allele burdens consistent with a dominant heterozygous population (allelic burden 55–65%) (T/S 0.367 vs 0.497, P = 0.037). This suggests that the high degree of proliferation of the MPN clone reduces TL and suggests the possibility that TL shortening may be indicative of progressive genomic instability during MPN progression. The TL of JAK2V617F-negative MPN patients was similar to JAK2V617F-positive counterparts (T/S 0.527 vs 0.507, P = 0.603), suggesting that the yet-to-be-discovered causative mutation(s) impact the mutated stem cell similarly to JAK2V617F, and that TL measurement may prove useful in the diagnostic workup of JAK2V617F-negative MPN. PMID:19005480

The association of telomere length with family violence and disruption.

PubMed

Drury, Stacy S; Mabile, Emily; Brett, Zoë H; Esteves, Kyle; Jones, Edward; Shirtcliff, Elizabeth A; Theall, Katherine P

2014-07-01

To enhance the understanding of biological mechanisms connecting early adversity and negative health, we examine the association between family interpersonal violence and disruption and telomere length in youth. These specific exposures were selected because of their established links with negative health consequences across the life-course. Children, age 5 to 15, were recruited from the greater New Orleans area, and exposure to family disruption and violence was assessed through caregiver report. Telomere length, from buccal cell DNA (buccal telomere length [bTL]), was determined by using monochrome multiplex quantitative real-time polymerase chain reaction. The association between bTL and adversity exposure was tested (n = 80). Cumulative exposure to interpersonal violence and family disruption was correlated with bTL. Controlling for other sociodemographic factors, bTL was significantly shorter in children with higher exposure to family violence and disruption. Witnessing family violence exerted a particularly potent impact. A significant gender interaction was found (β = -0.0086, SE = 0.0031, z test= -2.79, P = .0053) and analysis revealed the effect only in girls. bTL is a molecular biomarker of adversity and allostatic load that is detectable in childhood. The present results extend previous studies by demonstrating that telomeres are sensitive to adversity within the overarching family domain. These findings suggest that the family ecology may be an important target for interventions to reduce the biological impact of adversity in the lives of children. Copyright © 2014 by the American Academy of Pediatrics.

The Association of Telomere Length With Family Violence and Disruption

PubMed Central

Mabile, Emily; Brett, Zoë H.; Esteves, Kyle; Jones, Edward; Shirtcliff, Elizabeth A.; Theall, Katherine P.

2014-01-01

BACKGROUND: To enhance the understanding of biological mechanisms connecting early adversity and negative health, we examine the association between family interpersonal violence and disruption and telomere length in youth. These specific exposures were selected because of their established links with negative health consequences across the life-course. METHODS: Children, age 5 to 15, were recruited from the greater New Orleans area, and exposure to family disruption and violence was assessed through caregiver report. Telomere length, from buccal cell DNA (buccal telomere length [bTL]), was determined by using monochrome multiplex quantitative real-time polymerase chain reaction. The association between bTL and adversity exposure was tested (n = 80). RESULTS: Cumulative exposure to interpersonal violence and family disruption was correlated with bTL. Controlling for other sociodemographic factors, bTL was significantly shorter in children with higher exposure to family violence and disruption. Witnessing family violence exerted a particularly potent impact. A significant gender interaction was found (β = −0.0086, SE = 0.0031, z test= −2.79, P = .0053) and analysis revealed the effect only in girls. CONCLUSIONS: bTL is a molecular biomarker of adversity and allostatic load that is detectable in childhood. The present results extend previous studies by demonstrating that telomeres are sensitive to adversity within the overarching family domain. These findings suggest that the family ecology may be an important target for interventions to reduce the biological impact of adversity in the lives of children. PMID:24936002

An in silico investigation into the causes of telomere length heterogeneity and its implications for the Hayflick limit.

PubMed

Golubev, A; Khrustalev, S; Butov, A

2003-11-21

In telomerase-negative cell populations the mean telomere length (TL) decreases with increasing population doubling number (PD). A critically small TL is believed to stop cell proliferation at a cell-, age- and species-specific PD thus defining the Hayflick limit. However, positively skewed TL distributions are broad compared to differences between initial and final mean TL and strongly overlap at middle and late PD, which is inconsistent with a limiting role of TL. We used computer-assisted modelling to define what set of premises may account for the above. Our model incorporates the following concepts. DNA end replication problem: telomeres loose 1 shortening unit (SU) upon each cell division. Free radical-caused TL decrease: telomeres experience random events resulting in the loss of a random SU number within a remaining TL. Stochasticity of gene expression and cell differentiation: cells experience random events inducing mitoses or committing cells to proliferation arrest, the latter option requiring a specified number of mitoses to be passed. Cells whose TL reaches 1SU cannot divide. The proliferation kinetics of such virtual cells conforms to the transition probability model of cell cycle. When no committing events occur and at realistic SU estimates of the initial TL, maximal PD values far exceed the Hayflick limit observed in normal cells and are consistent with the crisis stage entered by transformed cells that have surpassed the Hayflick limit. At intermediate PD, symmetrical TL distributions are yielded. Upon introduction of committing events making the ratio of the rates of proliferating and committing events (P/C) range from 1.10 to 1.25, TL distributions at intermediate PD become positively skewed, and virtual cell clones show bimodal size distributions. At P/C as high as 1.25 the majority of virtual cells at maximal PD contain telomeres with TL>1SU. A 10% increase in P/C within the 1.10-1.25 range produces a two-fold increase in the maximal PD, which can reach values of up to 25 observed in rodent and some human cells. Increasing the number of committed mitoses from 0 to 10 can increases PD to about 50 observed in human fibroblasts. Introduction of the random TL breakage makes the shapes of TL distributions quite dissimilar from those observed in real cells. Telomere length decrease is a correlate of cell proliferation that cannot alone account for the Hayflick limit, which primarily depends on parameters of cell population kinetics. Free radical damage influences the Hayflick limit not through TL but rather by affecting the ratio of the rates of events that commit cells to mitoses or to proliferation arrest.

Comparison of telomere length and insulin-like growth factor-binding protein 7 promoter methylation between breast cancer tissues and adjacent normal tissues in Turkish women.

PubMed

Kaya, Zehra; Akkiprik, Mustafa; Karabulut, Sevgi; Peker, Irem; Gullu Amuran, Gokce; Ozmen, Tolga; Gulluoglu, Bahadır M; Kaya, Handan; Ozer, Ayse

2017-09-01

Both insulin-like growth factor-binding protein 7 (IGFBP7) and telomere length (TL) are associated with proliferation and senescence of human breast cancer. This study assessed the clinical significance of both TL and IGFBP7 methylation status in breast cancer tissues compared with adjacent normal tissues. We also investigated whether IGFBP7 methylation status could be affecting TL. Telomere length was measured by quantitative PCR to compare tumors with their adjacent normal tissues. The IGFBP7 promoter methylation status was evaluated by methylation-specific PCR and its expression levels were determined by western blotting. Telomeres were shorter in tumor tissues compared to controls (P<.0001). The mean TL was higher in breast cancer with invasive ductal carcinoma (IDC; n=72; P=.014) compared with other histological type (n=29), and TL in IDC with HER2 negative (n=53; P=.017) was higher than TL in IDC with HER2 positive (n=19). However, telomeres were shortened in advanced stages and growing tumors. IGFBP7 methylation was observed in 90% of tumor tissues and 59% of controls (P=.0002). Its frequency was significantly higher in IDC compared with invasive mixed carcinoma (IMC; P=.002) and it was not correlated either with protein expression or the other clinicopathological parameters. These results suggest that IGFBP7 promoter methylation and shorter TL in tumor compared with adjacent tissues may be predictive biomarkers for breast cancer. Telomere maintenance may be indicative of IDC and IDC with HER2 (-) of breast cancer. Further studies with larger number of cases are necessary to verify this association. © 2016 Wiley Periodicals, Inc.

Offspring telomere length in the long lived Alpine swift is negatively related to the age of their biological father and foster mother.

PubMed

Criscuolo, François; Zahn, Sandrine; Bize, Pierre

2017-09-01

A growing body of studies is showing that offspring telomere length (TL) can be influenced by the age of their parents. Such a relationship might be explained by variation in TL at conception (gamete effect) and/or by alteration of early growth conditions in species providing parental care. In a long-lived bird with bi-parental care, the Alpine swift ( Apus melba ), we exchanged an uneven number of 2 to 4-day-old nestlings between pairs as part of a brood size manipulation. Nestling TL was measured at 50 days after hatching, which allowed investigation of the influence of the age of both their biological and foster parents on offspring TL, after controlling for the manipulation. Nestling TL was negatively related to the age of their biological father and foster mother. Nestling TL did not differ between enlarged and reduced broods. These findings suggest that offspring from older males were fertilized by gametes with shorter telomeres, presumably due to a greater cell division history or a longer accumulation of damage, and that older females may have provided poorer parental care to their offspring. © 2017 The Author(s).

Telomere attrition, kidney function, and prevalent chronic kidney disease in the United States.

PubMed

Mazidi, Moshen; Rezaie, Peyman; Covic, Adriac; Malyszko, Jolanta; Rysz, Jacek; Kengne, Andre Pascal; Banach, Maciej

2017-10-06

Telomere length is an emerging novel biomarker of biologic age, cardiovascular risk and chronic medical conditions. Few studies have focused on the association between telomere length (TL) and kidney function. We investigated the association between TL and kidney function/prevalent chronic kidney disease (CKD) in US adults. The National Health and Nutrition Examination Survey (NHANES) participants with measured data on kidney function and TL from 1999 to 2002 were included. Estimated glomerular filtration rate (eGFR) was based on CKD Epidemiology Collaboration (CKD-EPI) equation. Urinary albumin excretion was assessed using urinary albumin-creatinine ratio (ACR). We used multivariable adjusted linear and logistic regression models, accounting for the survey design and sample weights. Of the 10568 eligible participants, 48.0% ( n =5020) were men. Their mean age was 44.1 years. eGFR significantly decreased and ACR significantly increased across increasing quarters of TL (all p <0.001). The association between TL and kidney function remained robust even after adjusting for potential confounding factors, but the association between TL and ACR was only borderline significant (β-coefficient= -0.012, p =0.056). The association of kidney function with a marker of cellular senescence suggests an underlying mechanism influencing the progression of nephropathy.

Colloidal thallium halide nanocrystals with reasonable luminescence, carrier mobility and diffusion length.

PubMed

Mir, Wasim J; Warankar, Avinash; Acharya, Ashutosh; Das, Shyamashis; Mandal, Pankaj; Nag, Angshuman

2017-06-01

Colloidal lead halide based perovskite nanocrystals (NCs) have been recently established as an interesting class of defect-tolerant NCs with potential for superior optoelectronic applications. The electronic band structure of thallium halides (TlX, where X = Br and I) show a strong resemblance to lead halide perovskites, where both Pb 2+ and Tl + exhibit a 6s 2 inert pair of electrons and strong spin-orbit coupling. Although the crystal structure of TlX is not perovskite, the similarities of its electronic structure with lead halide perovskites motivated us to prepare colloidal TlX NCs. These TlX NCs exhibit a wide bandgap (>2.5 eV or <500 nm) and the potential to exhibit a reduced density of deep defect states. Optical pump terahertz (THz) probe spectroscopy with excitation fluence in the range of 0.85-5.86 × 10 13 photons per cm 2 on NC films shows that the TlBr NCs possess high effective carrier mobility (∼220 to 329 cm 2 V -1 s -1 ), long diffusion length (∼0.77 to 0.98 μm), and reasonably high photoluminescence efficiency (∼10%). This combination of properties is remarkable compared to other wide-bandgap (>2.5 eV) semiconductor NCs, which suggests a reduction in the deep-defect states in the TlX NCs. Furthermore, the ultrafast carrier dynamics and temperature-dependent reversible structural phase transition together with its influence on the optical properties of the TlX NCs are studied.

Cardiac telomere length in heart development, function, and disease.

PubMed

Booth, S A; Charchar, F J

2017-07-01

Telomeres are repetitive nucleoprotein structures at chromosome ends, and a decrease in the number of these repeats, known as a reduction in telomere length (TL), triggers cellular senescence and apoptosis. Heart disease, the worldwide leading cause of death, often results from the loss of cardiac cells, which could be explained by decreases in TL. Due to the cell-specific regulation of TL, this review focuses on studies that have measured telomeres in heart cells and critically assesses the relationship between cardiac TL and heart function. There are several lines of evidence that have identified rapid changes in cardiac TL during the onset and progression of heart disease as well as at critical stages of development. There are also many factors, such as the loss of telomeric proteins, oxidative stress, and hypoxia, that decrease cardiac TL and heart function. In contrast, antioxidants, calorie restriction, and exercise can prevent both cardiac telomere attrition and the progression of heart disease. TL in the heart is also indicative of proliferative potential and could facilitate the identification of cells suitable for cardiac rejuvenation. Although these findings highlight the involvement of TL in heart function, there are important questions regarding the validity of animal models, as well as several confounding factors, that need to be considered when interpreting results and planning future research. With these in mind, elucidating the telomeric mechanisms involved in heart development and the transition to disease holds promise to prevent cardiac dysfunction and potentiate regeneration after injury. Copyright © 2017 the American Physiological Society.

[Osteological development of the vertebral column and caudal complex of Lujanus guttatus (Perciformes: Lutjanidae) larvae under rearing conditions].

PubMed

Rodríguez-Ibarra, Luz Estela; Abdo-de la Parra, María Isabel; Aguilar-Zárate, Gabriela; Valasco-Blanco, Gabriela; Ibarra-Castro, Leonardo

2015-03-01

The spotted rose snapper (Lutjanus guttatus) is an important commercial species in Mexico with good culture potential. The osteological study at early stages in this species is an important tool to confirm normal bone structure and for the detection of malformations that may occur during early development. This study was carried out in order to evaluate and describe the normal osteological development of the vertebral column and caudal complex of this species grown under controlled conditions. For this, a total of 540 larvae of L. guttatus, between 2.1 and 17.5 mm of total length (TL), were cultured during 36 days; culture conditions were 28 degrees C, 5.74 mg/L oxygen and 32.2 ups salinity with standard feeding rates. To detect growth changes, a sample of 15 organisms was daily taken from day one until day 36 of post-hatch (DPH). Samples were processed following standard techniques of clearing, and cartilage (alcian blue) and bone staining (alizarin red). Results showed that the vertebral column is composed of ten vertebrae in the abdominal region, and 14 vertebrae including the urostyle in the caudal region. The development of the axial skeleton starts with the neural arches and haemal arches at 3.8 mm TL. Caudal elements such as the hypurals and parahypural began to develop at 4.1 mm TL. Pre-flexion and flexion of the notochord and the formation of all hypurals were observed between 5.3 and 5.8 mm TL. Ossification of the vertebrae in the abdominal region and in some neural arches initiated at 9.5mm TL. In the caudal region, all the neural and haemal arches ossified at 10.2 mm TL. All the abdominal vertebrae and their respective neural arches and parapophyses ossified at 11.2 mm TL, while the elements of the caudal complex that ossified were the hypurals, parahypurals and modified haemal spines. All caudal fm rays, 12 neural spines and 3 haemal arches were ossified by 15.5 mm. The complete ossification process of this specie under laboratory culture conditions was observed when larvae reached 17.3 mm TL on 36 DPH. Detailed analysis of the osteological structures will allow a reference description to evaluate and detect malformations that may occur during the larval culture of the spotted rose snapper.

Leukocyte telomere length in Hispanic schizophrenia patients under treatment with olanzapine.

PubMed

Monroy-Jaramillo, Nancy; Rodríguez-Agudelo, Yaneth; Aviña-Cervantes, Luis Carlos; Roberts, David L; Velligan, Dawn I; Walss-Bass, Consuelo

2017-07-01

Different lines of evidence indicate that patients with schizophrenia (SZ) exhibit accelerated aging. Leukocyte telomere length (TL), an aging marker, is associated with age-related and chronic pathologies, including schizophrenia. We analyzed leukocyte TL in 170 SZ patients of Hispanic ancestry grouped based on antipsychotic treatment, compared to 126 matched controls. The group under treatment with atypical antipsychotics was further subdivided according to the risk of medication to cause metabolic syndrome (MetS). Our results show significant erosion in the TL of SZ patients under treatment with the atypical antipsychotics clozapine and olanzapine, which cause high-risk for MetS, compared to healthy controls and patients under treatment with medium and low-risk antipsychotics. However, when the analysis was done separately for clozapine and olanzapine, a significant difference remained only for olanzapine. These findings suggest that atypical antipsychotics that cause high-risk for MetS, particularly olanzapine, may modulate leukocyte TL in SZ patients. Future research is required to elucidate if in fact atypical antipsychotics are involved in TL maintenance in SZ subjects and the mechanism by which this occurs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Age-dependent associations between telomere length and environmental conditions in roe deer.

PubMed

Wilbourn, Rachael V; Froy, Hannah; McManus, Marie-Christina; Cheynel, Louise; Gaillard, Jean-Michel; Gilot-Fromont, Emmanuelle; Regis, Corinne; Rey, Benjamin; Pellerin, Maryline; Lemaître, Jean-François; Nussey, Daniel H

2017-09-01

Telomere length (TL) represents a promising biomarker of overall physiological state and of past environmental experiences, which could help us understand the drivers of life-history variation in natural populations. A growing number of studies in birds suggest that environmental stress or poor environmental conditions are associated with shortened TL, but studies of such relationships in wild mammals are lacking. Here, we compare leucocyte TL from cross-sectional samples collected from two French populations of roe deer which experience different environmental conditions. We found that, as predicted, TL was shorter in the population experiencing poor environmental conditions but that this difference was only significant in older individuals and was independent of sex and body mass. Unexpectedly, the difference was underpinned by a significant increase in TL with age in the population experiencing good environmental conditions, while there was no detectable relationship with age in poor conditions. These results demonstrate both the environmental sensitivity and complexity of telomere dynamics in natural mammal populations, and highlight the importance of longitudinal data to disentangle the within- and among-individual processes that generate them. © 2017 The Authors.

No difference in the rate of change in telomere length or telomerase activity in HIV-infected patients after three years of darunavir/ritonavir with and without nucleoside analogues in the MONET trial.

PubMed

Solomon, Ajantha; Tennakoon, Surekha; Leeansyah, Edwin; Arribas, Jose; Hill, Andrew; Van Delft, Yvon; Moecklinghoff, Christiane; Lewin, Sharon R

2014-01-01

To determine whether nucleos(t)ide reverse transcriptase inhibitors (NRTI) contribute to an accelerated loss in telomere length (TL) in HIV-infected patients on antiretroviral therapy (ART). Substudy of randomised controlled trial. Patients with HIV RNA <50 copies/mL on combination ART (n = 256) were randomised to darunavir/ritonavir (DRV/r) 800/100 mg once daily, either as monotherapy (n = 127) or with 2 NRTIs (n = 129) for up to 144 weeks. TL and telomerase activity was quantified on stored peripheral blood mononuclear cells (PBMC; n = 124) using quantitative real time PCR. Patients in the sub-study had a mean age of 44 years and had received NRTI for a mean of 6.4 years (range 1-20 years). As expected, older patients have significantly shorter TL (p = 0.006), while women had significantly longer TL (p = 0.026). There was no significant association between TL and either the duration of prior NRTI treatment (p = 0.894) or the use of a PI versus NNRTI (p = 0.107). There was no significant difference between patients who continued or ceased NRTI in the mean change/year of TL or telomerase (p = 0.580 and 0.280 respectively). Continuation versus cessation of NRTI treatment was not associated with an accelerated loss in TL or telomerase activity.

Growth and Maximum Size of Tiger Sharks (Galeocerdo cuvier) in Hawaii

PubMed Central

Meyer, Carl G.; O'Malley, Joseph M.; Papastamatiou, Yannis P.; Dale, Jonathan J.; Hutchinson, Melanie R.; Anderson, James M.; Royer, Mark A.; Holland, Kim N.

2014-01-01

Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13′17″N 109°52′14″W), in the southern Gulf of California (minimum distance between tag and recapture sites  =  approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates. PMID:24416287

Growth and maximum size of tiger sharks (Galeocerdo cuvier) in Hawaii.

PubMed

Meyer, Carl G; O'Malley, Joseph M; Papastamatiou, Yannis P; Dale, Jonathan J; Hutchinson, Melanie R; Anderson, James M; Royer, Mark A; Holland, Kim N

2014-01-01

Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13'17″N 109°52'14″W), in the southern Gulf of California (minimum distance between tag and recapture sites  =  approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates.

Molecular simulation of steady-state evaporation and condensation in the presence of a non-condensable gas

NASA Astrophysics Data System (ADS)

Liang, Zhi; Keblinski, Pawel

2018-02-01

Using molecular dynamics simulations, we study evaporation and condensation of fluid Ar in the presence of a non-condensable Ne gas in a nanochannel. The evaporation and condensation are driven by the temperature difference, ΔTL, between the evaporating and condensing liquid surfaces. The steady-state evaporation and condensation fluxes (JMD) are also affected by the Ne concentration, ρNe, and the nanochannel length. We find that across a wide range of ΔTL and ρNe, JMD is in good agreement with the prediction from Stefan's law and from Schrage relationships. Furthermore, for ΔTL less than ˜20% of the absolute average temperature, we find that both steady-state heat and mass fluxes are proportional to ΔTL. This allows us to determine the interfacial resistance to the heat and mass transfer and compare it with the corresponding resistances in the gas phase. In this context, we derive an analytical expression for the effective thermal conductivity of the gas region in the nanochannel and the mass transport interfacial resistance equivalent length, i.e., the length of the nanochannel for which the resistance to the mass flow is the same as the interfacial resistance to the mass flow.

Critical Care Admissions following Total Laryngectomy: Is It Time to Change Our Practice?

PubMed

Walijee, Hussein; Morgan, Alexandria; Gibson, Bethan; Berry, Sandeep; Jaffery, Ali

2016-01-01

Critical Care Unit (CCU) beds are a limited resource and in increasing demand. Studies have shown that complex head and neck patients can be safely managed on a ward setting given the appropriate staffing and support. This retrospective case series aims to quantify the CCU care received by patients following total laryngectomy (TL) at a District General Hospital (DGH) and compare patient outcomes in an attempt to inform current practice. Data relating to TL were collected over a 5-year period from 1st January 2010 to 31st December 2015. A total of 22 patients were included. All patients were admitted to CCU postoperatively for an average length of stay of 25.5 hours. 95% of these patients were admitted to CCU for the purpose of close monitoring only, not requiring any active treatment prior to discharge to the ward. 73% of total complications were encountered after the first 24 hours postoperatively at which point patients had been stepped down to ward care. Avoiding the use of CCU beds and instead providing the appropriate level of care on the ward would result in a potential cost saving of approximately £8,000 with no influence on patient morbidity and mortality.

Genome-wide association study of telomere length among South Asians identifies a second RTEL1 association signal

PubMed Central

Zhang, Chenan; Chen, Lin S; Gao, Jianjun; Roy, Shantanu; Shinkle, Justin; Sabarinathan, Mekala; Tong, Lin; Ahmed, Alauddin; Islam, Tariqul; Rakibuz-Zaman, Muhammad; Sarwar, Golam; Shahriar, Hasan; Rahman, Mahfuzar; Yunus, Mohammad; Jasmine, Farzana; Kibriya, Muhammad G; Ahsan, Habibul; Pierce, Brandon L

2018-01-01

Background Leucocyte telomere length (TL) is a potential biomarker of ageing and risk for age-related disease. Leucocyte TL is heritable and shows substantial differences by race/ethnicity. Recent genome-wide association studies (GWAS) report ~10 loci harbouring SNPs associated with leucocyte TL, but these studies focus primarily on populations of European ancestry. Objective This study aims to enhance our understanding of genetic determinants of TL across populations. Methods We performed a GWAS of TL using data on 5075 Bangladeshi adults. We measured TL using one of two technologies (qPCR or a Luminex-based method) and used standardised variables as TL phenotypes. Results Our results replicate previously reported associations in the TERC and TERT regions (P=2.2×10−8 and P=6.4×10−6, respectively). We observed a novel association signal in the RTEL1 gene (intronic SNP rs2297439; P=2.82×10−7) that is independent of previously reported TL-associated SNPs in this region. The minor allele for rs2297439 is common in South Asian populations (≥0.25) but at lower frequencies in other populations (eg, 0.07 in Northern Europeans). Among the eight other previously reported association signals, all were directionally consistent with our study, but only rs8105767 (ZNF208) was nominally significant (P=0.003). SNP-based heritability estimates were as high as 44% when analysing close relatives but much lower when analysing distant relatives only. Conclusions In this first GWAS of TL in a South Asian population, we replicate some, but not all, of the loci reported in prior GWAS of individuals of European ancestry, and we identify a novel second association signal at the RTEL1 locus. PMID:29151059

Growing Up Or Growing Old? Cellular Aging Linked With Testosterone Reactivity To Stress In Youth

PubMed Central

Drury, Stacy S.; Shirtcliff, Elizabeth A.; Shachet, Andrew; Phan, Jenny; Mabile, Emily; Brett, Zoë H.; Wren, Michael; Esteves, Kyle; Theall, Katherine P.

2014-01-01

Background Given the established relation between testosterone and aging in older adults, we tested whether buccal telomere length (TL), an established cellular biomarker of aging, was associated with testosterone levels in youth. Methods Children, mean age 10.2 years, were recruited from the greater New Orleans area and salivary testosterone was measured during both an acute stressor and diurnally. Buccal TL was measured using monochrome multiplex quantitative real-time PCR (MMQ-PCR). Testosterone and telomere length data was available on 77 individuals. The association between buccal TL and testosterone was tested using multivariate Generalized Estimating Equations (GEE) to account for clustering of children within families. Results Greater peak testosterone levels (β=-0.87, p < 0.01) and slower recovery (β=-0.56, p < 0.01) and reactivity (β = -1.22, p < 0.01) following a social stressor were significantly associated with shorter buccal TL after controlling for parental age at conception, child age, sex, sociodemographic factors and puberty. No association was initially present between diurnal measurements of testosterone or morning basal testosterone levels and buccal TL. Sex significantly moderated the relation between testosterone reactivity and buccal TL. Conclusions The association between testosterone and buccal TL supports gonadal maturation as a developmentally sensitive biomarker of aging within youth. As stress levels of testosterone were significantly associated with buccal TL, these findings are consistent with the growing literature linking stress exposure and accelerated maturation. The lack of association of diurnal testosterone or morning basal levels with buccal TL bolsters the notion of a shared stress-related maturational mechanism between cellular stress and the hypothalamic pituitary gonadal (HPG) axis. These data provide novel evidence supporting the interaction of aging, physiologic stress and cellular processes as an underlying mechanism linking negative health outcomes and early life stress. PMID:25010187

Lifecourse Adversity and Telomere Length in Older Women from Northeast Brazil.

PubMed

Oliveira, Bruna Silva; Zunzunegui, Maria Victoria; Quinlan, Jacklyn; Batistuzzo de Medeiros, Silvia Regina; Thomasini, Ronaldo Luis; Guerra, Ricardo Oliveira

2017-06-19

We examined associations between adverse childhood experiences (ACEs) and shorter telomere length (TL) in 83 older women, including 42 women with less than secondary education and 41 with secondary or more education in a city of Northeast Brazil, a region with substantial socioeconomic inequalities. The low education sample was selected from a representative survey at local neighborhood health centers, while the high education group consisted of a convenience sample recruited by advertising in community centers and centers affiliated with the local university. Relative leukocyte TL was measured by quantitative polymerase chain reaction from blood samples. ACEs were self-reported. Spline linear regression was fitted to assess the strength of the associations between ACEs and TL. Among women with low education, median TL was 1.02 compared with 0.64 in the high education group (p = 0.0001). Natural log-transformed T/S ratio as the dependent variable was used in analysis. Women with low education had been exposed to more ACEs, and among them those experiencing two or more ACEs had longer TL than women exposed to ≤1 ACEs (p = 0.03); among women with high education, this difference was not significant (p = 0.49). In analyses adjusted by age, education, and parental abuse of alcohol, the linear trend of higher TL with increasing ACEs was confirmed (p = 0.02), and the mean difference in TL between groups remained significant (p = 0.002). The unexpected positive relationship between low education and ACEs with TL suggests that older adults who have survived harsh conditions prevailing in Northeast Brazil have the longest TL of their birth cohort.

Nutrient bioassimilation capacity of aquacultured oysters: quantification of an ecosystem service.

PubMed

Higgins, Colleen B; Stephenson, Kurt; Brown, Bonnie L

2011-01-01

Like many coastal zones and estuaries, the Chesapeake Bay has been severely degraded by cultural eutrophication. Rising implementation costs and difficulty achieving nutrient reduction goals associated with point and nonpoint sources suggests that approaches supplemental to source reductions may prove useful in the future. Enhanced oyster aquaculture has been suggested as one potential policy initiative to help rid the Bay waters of excess nutrients via harvest of bioassimilated nutrients. To assess this potential, total nitrogen (TN), total phosphorous (TP), and total carbon (TC) content were measured in oyster tissue and shell at two floating-raft cultivation sites in the Chesapeake Bay. Models were developed based on the common market measurement of total length (TL) for aquacultured oysters, which was strongly correlated to the TN (R2 = 0.76), TP (R2 = 0.78), and TC (R2 = 0.76) content per oyster tissue and shell. These models provide resource managers with a tool to quantify net nutrient removal. Based on model estimates, 10(6) harvest-sized oysters (76 mm TL) remove 132 kg TN, 19 kg TP, and 3823 kg TC. In terms of nutrients removed per unit area, oyster harvest is an effective means of nutrient removal compared with other nonpoint source reduction strategies. At a density of 286 oysters m(-2), assuming no mortality, harvest size nutrient removal rates can be as high as 378 kg TN ha(-1), 54 kg TP ha(-1), and 10,934 kg TC ha(-1) for 76-mm oysters. Removing 1 t N from the Bay would require harvesting 7.7 million 76-mm TL cultivated oysters.

Estimation of spawning area of Pisodonophis sangjuensis Ji and Kim, 2011 (Pisces: Ophichthidae) based on leptocephali size and distribution

NASA Astrophysics Data System (ADS)

Ji, Hwan-Sung; Hwang, Kangseok; Choi, Jung Hwa; Cha, Hyung-Kee; Kim, Jin-Koo

2017-06-01

Pre-metamorphic leptocephali of Pisodonophis sangjuensis ( n = 91, 10.4-90.2 mm in total length, TL) were collected in the East China Sea for the first time. Pre-metamorphic leptocephali of P. sangjuensis, which were identified using mitochondrial DNA cytochrome c oxidase subunit I gene (mtDNA COI), are characterized by various combinations of morphological characters: 8 moderate to pronounced gut loops with the kidney terminating on the 6-7th loops; and 8 subcutaneous pigment patches on the tail just ventral to the notochord. Pisodonophis sangjuensis leptocephali were more numerously collected offshore than inshore around Jeju Island. The smallest leptocephali (< 15.0 mm TL) were collected from the south far from Jeju Island, and the largest leptocephali (> 100.0 mm TL) were collected from around Jeju Island and the southern coast of Korea. Our findings indicate that P. sangjuensis spawns offshore south of Jeju Island that is an area associated with high water temperature, and then the hatched leptocephali are transported to Jeju Island or the southern coast of Korea by the Tsushima Warm Current.

Traffic-Related Air Pollution and Telomere Length in Children and Adolescents Living in Fresno, CA: A Pilot Study.

PubMed

Lee, Eunice Y; Lin, Jue; Noth, Elizabeth M; Hammond, S Katharine; Nadeau, Kari C; Eisen, Ellen A; Balmes, John R

2017-05-01

The main objective of this pilot study was to gather preliminary information about how telomere length (TL) varies in relation to exposure to polycyclic aromatic hydrocarbons (PAHs) in children living in a highly polluted city. We conducted a cross-sectional study of children living in Fresno, California (n = 14). Subjects with and without asthma were selected based on their annual average PAH level in the 12-months prior to their blood draw. We measured relative telomere length from peripheral blood mononuclear cells (PBMC). We found an inverse linear relationship between average PAH level and TL (R = 0.69), as well as between age and TL (R = 0.21). Asthmatics had shorter mean telomere length than non-asthmatics (TLasthmatic = 1.13, TLnon-asthmatic = 1.29). These preliminary findings suggest that exposure to ambient PAH may play a role in telomere shortening.Become familiar with previous evidence suggesting that telomere length may be a biomarker of air pollution-induced cytotoxicity.Summarize the new findings on the association between polycyclic aromatic hydrocarbon (PAH) exposure and telomere length in adolescents, including those with asthma.Discuss the implications for recommendations and policies to mitigate the health and respiratory effects of traffic-related air pollution.

Tiger sharks can connect equatorial habitats and fisheries across the Atlantic Ocean basin

PubMed Central

Garla, Ricardo; Hazin, Fábio H. V.

2017-01-01

Increasing our knowledge about the spatial ecology of apex predators and their interactions with diverse habitats and fisheries is necessary for understanding the trophic mechanisms that underlie several aspects of marine ecosystem dynamics and for guiding informed management policies. A preliminary assessment of tiger shark (Galeocerdo cuvier) population structure off the oceanic insular system of Fernando de Noronha (FEN) and the large-scale movements performed by this species in the equatorial Atlantic Ocean was conducted using longline and handline fishing gear and satellite telemetry. A total of 25 sharks measuring 175–372 cm in total length (TL) were sampled. Most sharks were likely immature females ranging between 200 and 260 cm TL, with few individuals < 200 cm TL being caught. This contrasts greatly with the tiger shark size-distribution previously reported for coastal waters off the Brazilian mainland, where most individuals measured < 200 cm TL. Also, the movements of 8 individuals measuring 202–310 cm TL were assessed with satellite transmitters for a combined total of 757 days (mean = 94.6 days∙shark-1; SD = 65.6). These sharks exhibited a considerable variability in their horizontal movements, with three sharks showing a mostly resident behavior around FEN during the extent of the respective tracks, two sharks traveling west to the South American continent, and two sharks moving mostly along the middle of the oceanic basin, one of which ending up in the northern hemisphere. Moreover, one shark traveled east to the African continent, where it was eventually caught by fishers from Ivory Coast in less than 474 days at liberty. The present results suggest that young tiger sharks measuring < 200 cm TL make little use of insular oceanic habitats from the western South Atlantic Ocean, which agrees with a previously-hypothesized ontogenetic habitat shift from coastal to oceanic habitats experienced by juveniles of this species in this region. In addition, this study adds evidence that tiger sharks are able to connect marine trophic webs from the neritic provinces of the eastern and western margins of the Atlantic Ocean across the equatorial basin and that they may experience mortality induced by remote fisheries. All this information is extremely relevant for understanding the energetic balance of marine ecosystems as much as the exposure of this species to fishing pressure in this yet poorly-known region. PMID:28926627

Tiger sharks can connect equatorial habitats and fisheries across the Atlantic Ocean basin.

PubMed

Afonso, André S; Garla, Ricardo; Hazin, Fábio H V

2017-01-01

Increasing our knowledge about the spatial ecology of apex predators and their interactions with diverse habitats and fisheries is necessary for understanding the trophic mechanisms that underlie several aspects of marine ecosystem dynamics and for guiding informed management policies. A preliminary assessment of tiger shark (Galeocerdo cuvier) population structure off the oceanic insular system of Fernando de Noronha (FEN) and the large-scale movements performed by this species in the equatorial Atlantic Ocean was conducted using longline and handline fishing gear and satellite telemetry. A total of 25 sharks measuring 175-372 cm in total length (TL) were sampled. Most sharks were likely immature females ranging between 200 and 260 cm TL, with few individuals < 200 cm TL being caught. This contrasts greatly with the tiger shark size-distribution previously reported for coastal waters off the Brazilian mainland, where most individuals measured < 200 cm TL. Also, the movements of 8 individuals measuring 202-310 cm TL were assessed with satellite transmitters for a combined total of 757 days (mean = 94.6 days∙shark-1; SD = 65.6). These sharks exhibited a considerable variability in their horizontal movements, with three sharks showing a mostly resident behavior around FEN during the extent of the respective tracks, two sharks traveling west to the South American continent, and two sharks moving mostly along the middle of the oceanic basin, one of which ending up in the northern hemisphere. Moreover, one shark traveled east to the African continent, where it was eventually caught by fishers from Ivory Coast in less than 474 days at liberty. The present results suggest that young tiger sharks measuring < 200 cm TL make little use of insular oceanic habitats from the western South Atlantic Ocean, which agrees with a previously-hypothesized ontogenetic habitat shift from coastal to oceanic habitats experienced by juveniles of this species in this region. In addition, this study adds evidence that tiger sharks are able to connect marine trophic webs from the neritic provinces of the eastern and western margins of the Atlantic Ocean across the equatorial basin and that they may experience mortality induced by remote fisheries. All this information is extremely relevant for understanding the energetic balance of marine ecosystems as much as the exposure of this species to fishing pressure in this yet poorly-known region.

Telomere Length, Long-Term Black Carbon Exposure, and Cognitive Function in a Cohort of Older Men: The VA Normative Aging Study.

PubMed

Colicino, Elena; Wilson, Ander; Frisardi, Maria Chiara; Prada, Diddier; Power, Melinda C; Hoxha, Mirjam; Dioni, Laura; Spiro, Avron; Vokonas, Pantel S; Weisskopf, Marc G; Schwartz, Joel D; Baccarelli, Andrea A

2017-01-01

Long-term air pollution exposure has been associated with age-related cognitive impairment, possibly because of enhanced inflammation. Leukocytes with longer telomere length (TL) are more responsive to inflammatory stimuli, yet TL has not been evaluated in relation to air pollution and cognition. We assessed whether TL modifies the association of 1-year exposure to black carbon (BC), a marker of traffic-related air pollution, with cognitive function in older men, and we examined whether this modification is independent of age and of C-reactive protein (CRP), a marker of inflammation. Between 1999 and 2007, we conducted 1-3 cognitive examinations of 428 older men in the Veterans Affairs (VA) Normative Aging Study. We used covariate-adjusted repeated-measure logistic regression to estimate associations of 1-year BC exposure with relative odds of being a low scorer (≤ 25) on the Mini-Mental State Examination (MMSE), which is a proxy of poor cognition. Confounders included age, CRP, and lifestyle and sociodemographic factors. Each doubling in BC level was associated with 1.57 (95% CI: 1.20, 2.05) times higher odds of low MMSE scores. The BC-MMSE association was greater only among individuals with longer blood TL (5th quintile) (OR = 3.23; 95% CI: 1.37, 7.59; p = 0.04 for BC-by-TL-interaction). TL and CRP were associated neither with each other nor with MMSE. However, CRP modified the BC-MMSE relationship, with stronger associations only at higher CRP (5th quintile) and reference TL level (1st quintile) (OR = 2.68; 95% CI: 1.06, 6.79; p = 0.04 for BC-by-CRP-interaction). TL and CRP levels may help predict the impact of BC exposure on cognitive function in older men. Citation: Colicino E, Wilson A, Frisardi MC, Prada D, Power MC, Hoxha M, Dioni L, Spiro A III, Vokonas PS, Weisskopf MG, Schwartz JD, Baccarelli AA. 2017. Telomere length, long-term black carbon exposure, and cognitive function in a cohort of older men: the VA Normative Aging Study. Environ Health Perspect 125:76-81; http://dx.doi.org/10.1289/EHP241.

An alkaline and surfactant-tolerant lipase from Trichoderma lentiforme ACCC30425 with high application potential in the detergent industry.

PubMed

Wang, Yuzhou; Ma, Rui; Li, Shigui; Gong, Mingbo; Yao, Bin; Bai, Yingguo; Gu, Jingang

2018-06-05

Alkaline lipases with adaptability to low temperatures and strong surfactant tolerance are favorable for application in the detergent industry. In the present study, a lipase-encoding gene, TllipA, was cloned from Trichoderma lentiforme ACCC30425 and expressed in Pichia pastoris GS115. The purified recombinant TlLipA was found to have optimal activities at 50 °C and pH 9.5 and retain stable over the pH range of 6.0-10.0 and 40 °C and below. When using esters of different lengths as substrates, TlLipA showed preference for the medium length p-nitrophenyl octanoate. In comparison to commercial lipases, TlLipA demonstrated higher tolerance to various surfactants (SDS, Tween 20, and Triton X100) and retained more activities after incubation with Triton X100 for up to 24 h. These favorable characteristics make TlLipA prospective as an additive in the detergent industry.

Telomere length, ATM mutation status and cancer risk in Ataxia-Telangiectasia families.

PubMed

Renault, Anne-Laure; Mebirouk, Noura; Cavaciuti, Eve; Le Gal, Dorothée; Lecarpentier, Julie; d'Enghien, Catherine Dubois; Laugé, Anthony; Dondon, Marie-Gabrielle; Labbé, Martine; Lesca, Gaetan; Leroux, Dominique; Gladieff, Laurence; Adenis, Claude; Faivre, Laurence; Gilbert-Dussardier, Brigitte; Lortholary, Alain; Fricker, Jean-Pierre; Dahan, Karin; Bay, Jacques-Olivier; Longy, Michel; Buecher, Bruno; Janin, Nicolas; Zattara, Hélène; Berthet, Pascaline; Combès, Audrey; Coupier, Isabelle; Hall, Janet; Stoppa-Lyonnet, Dominique; Andrieu, Nadine; Lesueur, Fabienne

2017-10-01

Recent studies have linked constitutive telomere length (TL) to aging-related diseases including cancer at different sites. ATM participates in the signaling of telomere erosion, and inherited mutations in ATM have been associated with increased risk of cancer, particularly breast cancer. The goal of this study was to investigate whether carriage of an ATM mutation and TL interplay to modify cancer risk in ataxia-telangiectasia (A-T) families.The study population consisted of 284 heterozygous ATM mutation carriers (HetAT) and 174 non-carriers (non-HetAT) from 103 A-T families. Forty-eight HetAT and 14 non-HetAT individuals had cancer, among them 25 HetAT and 6 non-HetAT were diagnosed after blood sample collection. We measured mean TL using a quantitative PCR assay and genotyped seven single-nucleotide polymorphisms (SNPs) recurrently associated with TL in large population-based studies.HetAT individuals were at increased risk of cancer (OR = 2.3, 95%CI = 1.2-4.4, P = 0.01), and particularly of breast cancer for women (OR = 2.9, 95%CI = 1.2-7.1, P = 0.02), in comparison to their non-HetAT relatives. HetAT individuals had longer telomeres than non-HetAT individuals (P = 0.0008) but TL was not associated with cancer risk, and no significant interaction was observed between ATM mutation status and TL. Furthermore, rs9257445 (ZNF311) was associated with TL in HetAT subjects and rs6060627 (BCL2L1) modified cancer risk in HetAT and non-HetAT women.Our findings suggest that carriage of an ATM mutation impacts on the age-related TL shortening and that TL per se is not related to cancer risk in ATM carriers. TL measurement alone is not a good marker for predicting cancer risk in A-T families. © The Author 2017. Published by Oxford University Press.

Na(23)K(9)Tl(15.3): An Unusual Zintl Compound Containing Apparent Tl(5)(7)(-), Tl(4)(8)(-), Tl(3)(7)(-), and Tl(5)(-) Anions.

PubMed

Dong, Zhen-Chao; Corbett, John D.

1996-05-22

Reaction of the neat elements in tantalum containers at 400 degrees C and then 150 degrees C gives the pure title phase. X-ray crystallography shows that the hexagonal structure (P6(3)/mmc, Z = 2, a = 11.235(1) Å, b = 30.133(5) Å) contains relatively high symmetry clusters Tl(5)(7)(-) (D(3)(h)()), Tl(4)(8)(-) (C(3)(v)(), approximately T(d)), and the new Tl(3)(7)(-) (D(infinity)(h)()) plus Tl(5)(-), the last two disordered over the same elongated site in 1:2 proportions. Cation solvation of these anions is tight and specific, providing good Coulombic trapping of weakly bound electrons on the isolated cluster anions. The observed disorder makes the compound structurally a Zintl phase with a closed shell electron count. EHMO calculations on the novel Tl(3)(7)(-) reveal some bonding similarities with the isoelectronic CO(2), with two good sigma(s,p) bonding and two weakly bonding pi MO's. The Tl-Tl bond lengths therein (3.14 Å) are evidently consistent with multiple bonding. The weak temperature-independent paramagnetism and metallic conductivity (rho(293) approximately 90 &mgr;Omega.cm) of the phase are discussed.

Moderate-to-severe obstructive sleep apnea is associated with telomere lengthening.

PubMed

Polonis, Katarzyna; Somers, Virend K; Becari, Christiane; Covassin, Naima; Schulte, Phillip J; Druliner, Brooke R; Johnson, Ruth A; Narkiewicz, Krzysztof; Boardman, Lisa A; Singh, Prachi

2017-11-01

Obstructive sleep apnea (OSA) is associated with cardiometabolic diseases. Telomere shortening is linked to hypertension, diabetes mellitus, and cardiovascular diseases. Because these conditions are highly prevalent in OSA, we hypothesized that telomere length (TL) would be reduced in OSA patients. We identified 106 OSA and 104 non-OSA subjects who underwent polysomnography evaluation. Quantitative PCR was used to measure telomere length in genomic DNA isolated from peripheral blood samples. The association between OSA and TL was determined using unadjusted and adjusted linear models. There was no difference in TL between the OSA and non-OSA (control) group. However, we observed a J-shaped relationship between TL and OSA severity: the longest TL in moderate-to-severe OSA [4,918 ± 230 (SD) bp] and the shortest TL in mild OSA (4,735 ± 145 bp). Mean TL in moderate-to-severe OSA was significantly longer than in the control group after adjustment for age, sex, body mass index, hypertension, dyslipidemia, and depression (β = 96.0, 95% confidence interval: 15.4-176.6, P = 0.020). In conclusion, moderate-to-severe OSA is associated with telomere lengthening. Our findings support the idea that changes in TL are not unidirectional processes, such that telomere shortening occurs with age and disease but may be prolonged in moderate-to-severe OSA. NEW & NOTEWORTHY Here, we show that moderate-to-severe obstructive sleep apnea is associated with longer telomeres, independent of age and cardiovascular risk factors, challenging the hypothesis that telomere shortening is a unidirectional process related to age/disease. A better understanding of the mechanisms underlying telomere dynamics may identify targets for therapeutic intervention in cardiovascular aging/other chronic diseases. Copyright © 2017 the American Physiological Society.

Intraspecific variation in gill morphology of juvenile Nile perch, Lates niloticus, in Lake Nabugabo, Uganda

USGS Publications Warehouse

Paterson, Jaclyn A.; Chapman, Lauren J.; Schofield, Pamela J.

2010-01-01

Several studies have demonstrated intraspecific variation in fish gill size that relates to variation in dissolved oxygen (DO) availability across habitats. In Lake Nabugabo, East Africa, ecological change over the past 12 years has coincided with a shift in the distribution of introduced Nile perch such that a larger proportion of the population now inhabits waters in or near wetland ecotones where DO is lower than in open waters of the lake. In this study, we compared gill size of juvenile Nile perch between wetland and exposed (open-water) habitats of Lake Nabugabo in 2007, as well as between Nile perch collected in 1996 and 2007. For Nile perch of Lake Nabugabo [<20 cm total length (TL)], there was a significant habitat effect on some gill traits. In general, fish from wetland habitats were characterized by a longer total gill filament length and average gill filament length than conspecifics from exposed habitats. Nile perch collected from wetland areas in 2007 had significantly larger gills (total gill filament length) than Nile perch collected in 1996, but there was no difference detected between Nile perch collected from exposed sites in 2007 and conspecifics collected in 1996.

Telomere length is short in PCOS and oral contraceptive does not affect the telomerase activity in granulosa cells of patients with PCOS.

PubMed

Li, Ying; Deng, Bingbing; Ouyang, Nengyong; Yuan, Ping; Zheng, Lingyan; Wang, Wenjun

2017-07-01

Our study aimed to investigate the association of telomerase activity (TA) and telomere length (TL) in granulosa cells (GCs) with IVF outcomes of polycystic ovary syndrome (PCOS) patients, and the effects of oral contraceptive pill (OCP) pretreatment on these two parameters. One hundred sixty-three infertile women were enrolled and divided into a PCOS group (n = 65) and a non-PCOS group (n = 98). The PCOS group was further divided into an OCP pretreatment group (n = 35) and a non-OCP pretreatment group (n = 30), a TA <0.070 group (n = 34) and a TA ≥0.070 group (n = 31), and a TL <1 group (n = 41) and a TL ≥1 group (n = 24), respectively. No obvious differences were observed in TA between these groups. The TL was 0.971 in PCOS group and 1.118 in non-PCOS group (P = 0.005). The patients with TL ≥1 accounted for 36.9% in PCOS group and 54.1% in non-PCOS group (P = 0.032). The average duration of infertility for PCOS patients was 5 years in TA <0.070 group and 4 years in TA ≥0.070 group (P = 0.038), and 5 years in TL <1 group and 3 years in TL ≥1 group (P = 0.006), respectively. No obvious differences were observed in IVF outcomes between these groups. No obvious differences were observed in TA, TL, or IVF outcomes between OCP pretreatment group and non-OCP pretreatment group in PCOS patients. Shorter TL was found in PCOS patients. The TA levels did not change significantly in PCOS patients. PCOS patients with a lower TA level and shorter telomeres had an earlier onset of infertility symptoms. No predictive value was found for TA and TL in terms of embryo quality or IVF outcomes in PCOS patients, and no effect OCP pretreatment was observed on either TA and TL.

PUFA Status and Methylmercury Exposure Are Not Associated with Leukocyte Telomere Length in Mothers or Their Children in the Seychelles Child Development Study.

PubMed

Yeates, Alison J; Thurston, Sally W; Li, Huiqi; Mulhern, Maria S; McSorley, Emeir M; Watson, Gene E; Shamlaye, Conrad F; Strain, J J; Myers, Gary J; Davidson, Philip W; van Wijngaarden, Edwin; Broberg, Karin

2017-11-01

Background: Leukocyte telomere length (TL) is associated with age-related diseases and early mortality, but there is a lack of data on the determinants of TL in early life. Evidence suggests that dietary intake of marine n-3 (ω-3) polyunsaturated fatty acids (PUFAs) is protective of telomere attrition, yet the effect of methylmercury exposure, also found in fish, on TL is unknown. Objective: The aim of this study was to investigate the associations between prenatal PUFA status, methylmercury exposure, and TL in mothers and children in the SCDS (Seychelles Child Development Study), for whom fish consumption is high. Methods: Blood samples collected from 229 mothers (at 28 wk gestation and delivery) and children (at 5 y of age) in the SCDS first nutrition cohort were analyzed for PUFA concentrations. Prenatal mercury was measured in maternal hair collected at delivery. Postnatal mercury was also measured in children's hair samples with the use of a cumulative metric derived from values obtained at 3-5 y of age. Relative TL was measured in blood obtained from mothers at delivery, in cord blood, and in children at 5 y of age by quantitative polymerase chain reaction. Linear regression models were used to investigate the associations between PUFA status, methylmercury exposure, and TL. Results: Neither prenatal PUFA status or methylmercury exposure was associated with TL of the mother or child or with TL attrition rate. However, a higher prenatal n-6:n-3 PUFA ratio was significantly associated with longer TLs in the mothers (β = 0.001, P = 0.048). Child PUFA status and methylmercury exposure were not associated with child TL. However, higher family Hollingshead socioeconomic status (SES) scores at 9 mo of age were significantly associated with longer TLs in cord blood (β = 0.005, P = 0.03). Conclusions: We found no evidence that PUFA status or methylmercury exposure are determinants of TL in either the mother or child. However, our results support the hypothesis that family SES may be associated with child TL. © 2017 American Society for Nutrition.

Chromosome Characteristic of Peranakan Etawa (PE) Goat (Capra hircus Linn.) as Indonesian Local Breed

NASA Astrophysics Data System (ADS)

Putri, A. R. I.; Ciptadi, G.; Warih, A. P.

2018-02-01

Chromosome characteristics of Peranakan Etawa (PE) goat needs to be analyzed because information about Indonesian goat races is very limited. The purpose of this research was to determine the characteristics of PE goat chromosome as basic data as one of the genetic local resources. Blood was collected from pair of PE goat at Sumber Sekar Field Laboratory, Faculty of Animal Husbandry, Brawijaya University, Malang. Blood cultured using standard cytogenetic technique and stained with G-Banding. Observations being done in metaphase cells and analyzed using Genus Cytovision Image. Chromosomes arranged and numbered by standard goat karyotype. The result of this research showed that PE goat had number of chromosomes 2n=60, consisting of 29 pairs of autosome and a pair of sex chromosomes. Female goat had average of total length (TL) of autosome ranged from 47.91 µm±6.46 to 22.12 µm±3.33. TL of chromosome X are 45.96 µm±4,59 and 44.45 µm±3,96. Centromeric index (Ci) of chromosome X, 31,74 and 32,80. PE goat had average of TL of autosome ranged from 58.20µm±6.72 to 18.97µm±2.82. TL of chromosome X is 56,42µm±7,38 and Y chromosome is 15,80 µm±3,24. Ci in chromosome X and Y are 19.34 and 46.84. These results concluded that the total of goat chromosome was 60 with types of autosomal chromosomes were acrocentric as many as 58 chromosomes and pair of sex chromosomes XX and XY, X classified as subtelocentric and Y submetacentric.

No Difference in the Rate of Change in Telomere Length or Telomerase Activity in HIV-Infected Patients after Three Years of Darunavir/Ritonavir with and without Nucleoside Analogues in the MONET Trial

PubMed Central

Solomon, Ajantha; Tennakoon, Surekha; Leeansyah, Edwin; Arribas, Jose; Hill, Andrew; Van Delft, Yvon; Moecklinghoff, Christiane; Lewin, Sharon R.

2014-01-01

Objective To determine whether nucleos(t)ide reverse transcriptase inhibitors (NRTI) contribute to an accelerated loss in telomere length (TL) in HIV-infected patients on antiretroviral therapy (ART). Design Substudy of randomised controlled trial. Methods Patients with HIV RNA <50 copies/mL on combination ART (n = 256) were randomised to darunavir/ritonavir (DRV/r) 800/100 mg once daily, either as monotherapy (n = 127) or with 2 NRTIs (n = 129) for up to 144 weeks. TL and telomerase activity was quantified on stored peripheral blood mononuclear cells (PBMC; n = 124) using quantitative real time PCR. Results Patients in the sub-study had a mean age of 44 years and had received NRTI for a mean of 6.4 years (range 1–20 years). As expected, older patients have significantly shorter TL (p = 0.006), while women had significantly longer TL (p = 0.026). There was no significant association between TL and either the duration of prior NRTI treatment (p = 0.894) or the use of a PI versus NNRTI (p = 0.107). There was no significant difference between patients who continued or ceased NRTI in the mean change/year of TL or telomerase (p = 0.580 and 0.280 respectively). Conclusion Continuation versus cessation of NRTI treatment was not associated with an accelerated loss in TL or telomerase activity. PMID:25368992

Traumatic stress and cellular senescence: The role of war-captivity and homecoming stressors in later life telomere length.

PubMed

Stein, Jacob Y; Levin, Yafit; Uziel, Orit; Abumock, Heba; Solomon, Zahava

2018-05-30

Telomere length (TL) serves as a biomarker of cellular senescence and is a robust predictor of mortality. The association between traumatic stress and TL erosion is rapidly realized, as are the complexities of this relation that include links to posttraumatic stress disorder (PTSD), depression, and psychosocial factors. Nevertheless, the relation between specific stressors in early adulthood and TL in later life, specifically among populations that have undergone extreme stress in early adulthood are largely uninvestigated. Examining 99 Israeli former prisoners of war (ex-POWs) 18 and 42 years after repatriation, the current study investigated the role that specific stressors during captivity (i.e., physical abuse, nourishment deprivation and solitary confinement) and homecoming (i.e., received social-support, loss of place in the family, loneliness and sense of being accused) play in predicting TL 42 years post-repatriation. Intercorrelations analysis and a hierarchical linear regression were utilized. Variables that have been empirically associated with TL: age, BMI, physical activity, smoking, substance abuse, negative life events since repatriation, depression and PTSD symptoms were controlled for in the regression. Solitary confinement during captivity, and loss of place in the family, loneliness and being accused at homecoming predicted shorter telomeres in later life. The remaining stressors did not significantly predict TL. These findings suggest that an adequate understanding of TL after trauma must consider the unique contributions of specific types of stressors across the lifespan, and particularly account for interpersonal deficits. The findings may inform preventive interventions aimed at improving ex-POWs' longevity and well-being. Copyright © 2018. Published by Elsevier B.V.

FTO associations with obesity and telomere length.

PubMed

Zhou, Yuling; Hambly, Brett D; McLachlan, Craig S

2017-09-01

This review examines the biology of the Fat mass- and obesity-associated gene (FTO), and the implications of genetic association of FTO SNPs with obesity and genetic aging. Notably, we focus on the role of FTO in the regulation of methylation status as possible regulators of weight gain and genetic aging. We present a theoretical review of the FTO gene with a particular emphasis on associations with UCP2, AMPK, RBL2, IRX3, CUX1, mTORC1 and hormones involved in hunger regulation. These associations are important for dietary behavior regulation and cellular nutrient sensing via amino acids. We suggest that these pathways may also influence telomere regulation. Telomere length (TL) attrition may be influenced by obesity-related inflammation and oxidative stress, and FTO gene-involved pathways. There is additional emerging evidence to suggest that telomere length and obesity are bi-directionally associated. However, the role of obesity risk-related genotypes and associations with TL are not well understood. The FTO gene may influence pathways implicated in regulation of TL, which could help to explain some of the non-consistent relationship between weight phenotype and telomere length that is observed in population studies investigating obesity.

Thermoluminescence (TL) properties and x-ray diffraction (XRD) analysis of high purity CaSO4:Dy TL material

NASA Astrophysics Data System (ADS)

Kamarudin, Nadira; Abdullah, Wan Saffiey Wan; Hamid, Muhammad Azmi Abdul; Dollah, Mohd Taufik

2014-09-01

This paper presents the characterization and TL properties of dysprosium (Dy) doped calcium sulfate (CaSO4) TL material produced by co-precipitation technique with 0.5mol% concentration of dopant. The morphology of the produced TL material was studied using scanning electron microscope (SEM) and the micrograph shows that rectangular parallelepiped shaped crystal with the average of 150 μm in length were produced. The crystallinity of the produced powder was studied using x-ray powder diffraction (XRD). The XRD spectra show that the TL material produced is high purity anhydrite CaSO4 with average crystallite size of 74 nm with orthorhombic crystal system. The TL behavior of produced CaSO4:Dy was studied using a TLD reader after exposure to gamma ray by Co60 source with the doses of 1,5 and 10 Gy. The glow curve shows linear response with glow peak around 230°C which is desired development in the field of radiation dosimetry.

Shorter telomere length in peripheral blood lymphocytes of workers exposed to polycyclic aromatic hydrocarbons.

PubMed

Pavanello, Sofia; Pesatori, Angela-C; Dioni, Laura; Hoxha, Mirjam; Bollati, Valentina; Siwinska, Ewa; Mielzyńska, Danuta; Bolognesi, Claudia; Bertazzi, Pier-Alberto; Baccarelli, Andrea

2010-02-01

Shorter telomere length (TL) in peripheral blood lymphocytes (PBLs) is predictive of lung cancer risk. Polycyclic aromatic hydrocarbons (PAHs) are established lung carcinogens that cause chromosome instability. Whether PAH exposure and its molecular effects are linked with shorter TL has never been evaluated. In the present study, we investigated the effect of chronic exposure to PAHs on TL measured in PBLs of Polish male non-current smoking cokeoven workers and matched controls. PAH exposure and molecular effects were characterized using measures of internal dose (urinary 1-pyrenol), effective dose [anti-benzo[a]pyrene diolepoxide (anti-BPDE)-DNA adduct], genetic instability (micronuclei, MN) and DNA methylation [p53 promoter and Alu and long interspersed nuclear element-1 (LINE-1) repetitive elements, as surrogate measures of global methylation] in PBLs. TL was measured by real-time polymerase chain reaction. Cokeoven workers were heavily exposed to PAHs (79% exceeded the urinary 1-pyrenol biological exposure index) and exhibited lower TL (P = 0.038) than controls, as well as higher levels of genetic and chromosomal alterations [i.e. anti-BPDE-DNA adduct and MN (P < 0.0001)] and epigenetic changes [i.e. p53 gene-specific promoter and global methylation (P

Shorter telomere length in peripheral blood lymphocytes of workers exposed to polycyclic aromatic hydrocarbons

PubMed Central

Pavanello, Sofia; Pesatori, Angela-C.; Dioni, Laura; Hoxha, Mirjam; Bollati, Valentina; Siwinska, Ewa; Mielzyńska, Danuta; Bolognesi, Claudia; Bertazzi, Pier-Alberto; Baccarelli, Andrea

2010-01-01

Shorter telomere length (TL) in peripheral blood lymphocytes (PBLs) is predictive of lung cancer risk. Polycyclic aromatic hydrocarbons (PAHs) are established lung carcinogens that cause chromosome instability. Whether PAH exposure and its molecular effects are linked with shorter TL has never been evaluated. In the present study, we investigated the effect of chronic exposure to PAHs on TL measured in PBLs of Polish male non-current smoking cokeoven workers and matched controls. PAH exposure and molecular effects were characterized using measures of internal dose (urinary 1-pyrenol), effective dose [anti-benzo[a]pyrene diolepoxide (anti-BPDE)–DNA adduct], genetic instability (micronuclei, MN) and DNA methylation [p53 promoter and Alu and long interspersed nuclear element-1 (LINE-1) repetitive elements, as surrogate measures of global methylation] in PBLs. TL was measured by real-time polymerase chain reaction. Cokeoven workers were heavily exposed to PAHs (79% exceeded the urinary 1-pyrenol biological exposure index) and exhibited lower TL (P = 0.038) than controls, as well as higher levels of genetic and chromosomal alterations [i.e. anti-BPDE–DNA adduct and MN (P < 0.0001)] and epigenetic changes [i.e. p53 gene-specific promoter and global methylation (P ≤ 0.001)]. TL decreased with longer duration of work as cokeoven worker (P = 0.039) and in all subjects with higher levels of anti-BPDE–DNA adduct (P = 0.042), p53 hypomethylation (P = 0.005) and MN (P = 0.009). In multivariate analysis, years of work in cokery (P = 0.008) and p53 hypomethylation (P = 0.001) were the principal determinants of shorter TL. Our results indicate that shorter TL is associated with chronic PAH exposure. The interrelations with other genetic and epigenetic mechanisms in our data suggest that shorter TL could be a central event in PAH carcinogenesis. PMID:19892797

Short telomere length is associated with impaired cognitive performance in European ancestry cohorts.

PubMed

Hägg, S; Zhan, Y; Karlsson, R; Gerritsen, L; Ploner, A; van der Lee, S J; Broer, L; Deelen, J; Marioni, R E; Wong, A; Lundquist, A; Zhu, G; Hansell, N K; Sillanpää, E; Fedko, I O; Amin, N A; Beekman, M; de Craen, A J M; Degerman, S; Harris, S E; Kan, K-J; Martin-Ruiz, C M; Montgomery, G W; Adolfsson, A N; Reynolds, C A; Samani, N J; Suchiman, H E D; Viljanen, A; von Zglinicki, T; Wright, M J; Hottenga, J-J; Boomsma, D I; Rantanen, T; Kaprio, J A; Nyholt, D R; Martin, N G; Nyberg, L; Adolfsson, R; Kuh, D; Starr, J M; Deary, I J; Slagboom, P E; van Duijn, C M; Codd, V; Pedersen, N L

2017-04-18

The association between telomere length (TL) dynamics on cognitive performance over the life-course is not well understood. This study meta-analyses observational and causal associations between TL and six cognitive traits, with stratifications on APOE genotype, in a Mendelian Randomization (MR) framework. Twelve European cohorts (N=17 052; mean age=59.2±8.8 years) provided results for associations between qPCR-measured TL (T/S-ratio scale) and general cognitive function, mini-mental state exam (MMSE), processing speed by digit symbol substitution test (DSST), visuospatial functioning, memory and executive functioning (STROOP). In addition, a genetic risk score (GRS) for TL including seven known genetic variants for TL was calculated, and used in associations with cognitive traits as outcomes in all cohorts. Observational analyses showed that longer telomeres were associated with better scores on DSST (β=0.051 per s.d.-increase of TL; 95% confidence interval (CI): 0.024, 0.077; P=0.0002), and MMSE (β=0.025; 95% CI: 0.002, 0.047; P=0.03), and faster STROOP (β=-0.053; 95% CI: -0.087, -0.018; P=0.003). Effects for DSST were stronger in APOE ɛ4 non-carriers (β=0.081; 95% CI: 0.045, 0.117; P=1.0 × 10 -5 ), whereas carriers performed better in STROOP (β=-0.074; 95% CI: -0.140, -0.009; P=0.03). Causal associations were found for STROOP only (β=-0.598 per s.d.-increase of TL; 95% CI: -1.125, -0.072; P=0.026), with a larger effect in ɛ4-carriers (β=-0.699; 95% CI: -1.330, -0.069; P=0.03). Two-sample replication analyses using CHARGE summary statistics showed causal effects between TL and general cognitive function and DSST, but not with STROOP. In conclusion, we suggest causal effects from longer TL on better cognitive performance, where APOE ɛ4-carriers might be at differential risk.

Genome-wide association study of telomere length among South Asians identifies a second RTEL1 association signal.

PubMed

Delgado, Dayana A; Zhang, Chenan; Chen, Lin S; Gao, Jianjun; Roy, Shantanu; Shinkle, Justin; Sabarinathan, Mekala; Argos, Maria; Tong, Lin; Ahmed, Alauddin; Islam, Tariqul; Rakibuz-Zaman, Muhammad; Sarwar, Golam; Shahriar, Hasan; Rahman, Mahfuzar; Yunus, Mohammad; Jasmine, Farzana; Kibriya, Muhammad G; Ahsan, Habibul; Pierce, Brandon L

2018-01-01

Leucocyte telomere length (TL) is a potential biomarker of ageing and risk for age-related disease. Leucocyte TL is heritable and shows substantial differences by race/ethnicity. Recent genome-wide association studies (GWAS) report ~10 loci harbouring SNPs associated with leucocyte TL, but these studies focus primarily on populations of European ancestry. This study aims to enhance our understanding of genetic determinants of TL across populations. We performed a GWAS of TL using data on 5075 Bangladeshi adults. We measured TL using one of two technologies (qPCR or a Luminex-based method) and used standardised variables as TL phenotypes. Our results replicate previously reported associations in the TERC and TERT regions (P=2.2×10 -8 and P=6.4×10 -6 , respectively). We observed a novel association signal in the RTEL1 gene (intronic SNP rs2297439; P=2.82×10 -7 ) that is independent of previously reported TL-associated SNPs in this region. The minor allele for rs2297439 is common in South Asian populations (≥0.25) but at lower frequencies in other populations (eg, 0.07 in Northern Europeans). Among the eight other previously reported association signals, all were directionally consistent with our study, but only rs8105767 ( ZNF208 ) was nominally significant (P=0.003). SNP-based heritability estimates were as high as 44% when analysing close relatives but much lower when analysing distant relatives only. In this first GWAS of TL in a South Asian population, we replicate some, but not all, of the loci reported in prior GWAS of individuals of European ancestry, and we identify a novel second association signal at the RTEL1 locus. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Population dynamics of bowfin in a south Georgia reservoir: latitudinal comparisons of population structure, growth, and mortality

USGS Publications Warehouse

Porter, Nicholas J.; Bonvechio, Timothy F.; McCormick, Joshua L.; Quist, Michael

2014-01-01

The objectives of this study were to evaluate the population dynamics of bowfin (Amia calva) in Lake Lindsay Grace, Georgia, and to compare those dynamics to other bowfin populations. Relative abundance of bowfin sampled in 2010 in Lake Lindsay Grace was low and variable (mean±SD; 2.7±4.7 fish per hour of electrofishing). Total length (TL) of bowfin collected in Lake Lindsay Grace varied from 233–683 mm. Age of bowfin in Lake Lindsay Grace varied from 0–5 yr. Total annual mortality (A) was estimated at 68%. Both sexes appeared to be fully mature by age 2 with gonadosomatic index values above 8 for females and close to 1 for males. The majority of females were older, longer, and heavier than males. Bowfin in Lake Lindsay Grace had fast growth up to age 4 and higher total annual mortality than the other populations examined in this study. A chi-square test indicated that size structure of bowfin from Lake Lindsay Grace was different than those of a Louisiana population and two bowfin populations from the upper Mississippi River. To further assess bowfin size structure, we proposed standard length (i.e., TL) categories: stock (200 mm, 8 inches), quality (350 mm, 14 inches), preferred (460 mm, 18 inches), memorable (560 mm, 22, inches), and trophy (710 mm, 28 inches). Because our knowledge of bowfin ecology is limited, additional understanding of bowfin population dynamics provides important insight that can be used in management of bowfin across their distribution.

Visual implant elastomer and anchor tag retention in largemouth bass

USGS Publications Warehouse

Hartman, K.J.; Janney, E.C.

2006-01-01

We double-marked largemouth bass Micropterus salmoides with Floy FD-68B anchor tags and visible implant elastomer (VIE) marks before stocking to compare retention of the two marks for age-0 (178 mm total length [TL]) and age-1 (273 mm TL) largemouth bass. In a short-term (31-d) evaluation, retention rate of anchor tags was over 94% for each age-class and retention of VIE marks was 98% in both age-classes. In a longer-term comparison of fish stocked into the Ohio River, retention was substantially higher for VIE marks (92.9%) than for anchor tags (42.9%) after 403 d (ages combined). Although anchor tags had high retention in two sizes of largemouth bass during the short-term experiment, they should not be used in situations where accurate identification of marked fish is required for periods longer than 123 d. ?? Copyright by the American Fisheries Society 2006.

Telomere length and genetics are independent colorectal tumour risk factors in an evaluation of biomarkers in normal bowel.

PubMed

Fernandez-Rozadilla, Ceres; Kartsonaki, Christiana; Woolley, Connor; McClellan, Michael; Whittington, Deb; Horgan, Gareth; Leedham, Simon; Kriaucionis, Skirmantas; East, James; Tomlinson, Ian

2018-03-06

Colorectal cancer (CRC) screening might be improved by using a measure of prior risk to modulate screening intensity or the faecal immunochemical test threshold. Intermediate molecular biomarkers could aid risk prediction by capturing both known and unknown risk factors. We sampled normal bowel mucosa from the proximal colon, distal colon and rectum of 317 individuals undergoing colonoscopy. We defined cases as having a personal history of colorectal polyp(s)/cancer, and controls as having no history of colorectal neoplasia. Molecular analyses were performed for: telomere length (TL); global methylation; and the expression of genes in molecular pathways associated with colorectal tumourigenesis. We also calculated a polygenic risk score (PRS) based on CRC susceptibility polymorphisms. Bowel TL was significantly longer in cases than controls, but was not associated with blood TL. PRS was significantly and independently higher in cases. Hypermethylation showed a suggestive association with case:control status. No gene or pathway was differentially expressed between cases and controls. Gene expression often varied considerably between bowel locations. PRS and bowel TL (but not blood TL) may be clinically-useful predictors of CRC risk. Sample collection to assess these biomarkers is feasible in clinical practice, especially where population screening uses flexible sigmoidoscopy or colonoscopy.

Association of telomere length with general cognitive trajectories: a meta-analysis of four prospective cohort studies.

PubMed

Zhan, Yiqiang; Clements, Mark S; Roberts, Rosebud O; Vassilaki, Maria; Druliner, Brooke R; Boardman, Lisa A; Petersen, Ronald C; Reynolds, Chandra A; Pedersen, Nancy L; Hägg, Sara

2018-06-02

To investigate the association of telomere length (TL) with trajectories of general cognitive abilities, we used data on 5955 participants from the Sex Differences in Health and Aging Study and the Swedish Adoption/Twin Study of Aging in Sweden, and the Mayo Clinic Study of Aging, and the Health and Retirement Study in the United States. TL was measured at baseline, while general cognitive ability was assessed repeatedly up to 7 occasions. Latent growth curve models were used to examine the associations. One standard deviation increase of TL was associated with 0.021 unit increase (95% confidence interval [CI]: 0.001, 0.042) of standardized mean general cognitive ability. After controlling for sex, the point estimate remained similar (0.019) with a wider CI (95% CI: -0.002, 0.039). The association was attenuated with adjustment for educational attainment (0.009, 95% CI: -0.009, 0.028). No strong evidence was observed for the association of TL and decline in general cognitive ability. Longer TL was associated with higher general cognitive ability levels in the age-adjusted models but not in the models including all covariates, nor with cognitive decline. Copyright © 2018 Elsevier Inc. All rights reserved.

Using pharyngeal teeth and chewing pads to estimate juvenile Silver Carp total length in the La Grange Reach, Illinois River

USGS Publications Warehouse

Lampo, Eli G.; Knights, Brent C.; Vallazza, Jon; Anderson, Cory A.; Rechkemmer, Will T.; Solomon, Levi E.; Casper, Andrew F.; Pendleton, Richard M.; Lamer, James T.

2017-01-01

The Silver Carp Hypophthalmichthys molitrix is an invasive species in the Mississippi River basin; an understanding of their vulnerability to predation as juveniles may inform control by native predators and predator enhancement (e.g., stocking). Digestion of Silver Carp prey recovered from diets makes it difficult to determine the size‐classes that are most vulnerable to predation by native fishes. The objective of this study was to determine whether the sizes of the chewing pad (CP), pharyngeal teeth (PT), and pharyngeal arch (PA)—the Silver Carp structures most often found intact in predator diets—were predictive of the TL of prey Silver Carp. During 2014 and 2015, juvenile Silver Carp (n = 136; <180 mm) were collected using 60‐Hz pulsed‐DC electrofishing and mini‐fyke nets in the La Grange reach of the Illinois River. We extracted Silver Carp CPs (n = 136 fish) and PAs with PT intact (n = 129 fish) and measured CP length (CPL) and width (CPW), eight reproducible PT landmarks (PT1L–PT4L; PT1W–PT4W), and four reproducible PA landmarks (PA1–PA4) to the nearest 0.01 µm. Using simple linear regression, we found a strong predictive relationship between measurements of CP, PT, or PA and the TL of Silver Carp. The CPL (r2 = 0.94) and CPW (r2 = 0.94) had the strongest relationships with Silver Carp TL, followed by PA1 (r2 = 0.89) and PT1L (r2 = 0.87). These strong relationships suggest that all three structures could be used in diet analyses to accurately estimate Silver Carp TL and thus further our understanding of predator–prey dynamics for this high‐risk invasive species.

[Size structure as evidence of population establishment of Pterois volitans (Scorpaeniformes: Scorpaenidae) in the South Mexican Caribbean].

PubMed

Sabido-Itzá, Miguel Mateo; Medina-Quej, Alejandro; de Jesús-Navarrete, Alberto; Gómez-Poot, Jorge Manuel; García-Rivas, María del Carmen

2016-03-01

The lionfish (P. volitans) has now invaded all the Mexican Caribbean and Gulf of Mexico, with the potential to cause negative impacts on the reefs. In the South Mexican Caribbean was firstly reported in July 2009, and six years after this report, some control measures such as fish tournament and local marketing have been implemented. However, information on its biology and invasion is still-lacking, so this study analyzed the population structure of 2 164 organisms collected from 2009 to 2012. An increase was observed in sizes for each year averaging Total length (Tl): 118 ± 34.8, 133 ± 56.3, 187 ± 74.8 and 219 ± 72.4 mm, respectively. Lionfish establishment at the study site is shown for the presence of juveniles’ sizes 20 mm TL up to 375 mm TL. When the back-calculation was obtained, we estimated that the larger fish could have recruited in early 2006, three years before the first report was made. A continuous population monitoring and an ecological study, will allow us to clarify the real impact in the ecosystems of the region and so to propose the most effective control actions.

Telomere length is a prognostic biomarker in elderly advanced ovarian cancer patients: a multicenter GINECO study

PubMed Central

Falandry, Claire; Horard, Béatrice; Bruyas, Amandine; Legouffe, Eric; Cretin, Jacques; Meunier, Jérôme; Alexandre, Jérôme; Delecroix, Valérie; Fabbro, Michel; Certain, Marie-Noëlle; Maraval-Gaget, Raymonde; Pujade-Lauraine, Eric; Gilson, Eric; Freyer, Gilles

2015-01-01

Purpose Age induces a progressive decline in functional reserve and impacts cancer treatments. Telomere attrition leads to tissue senescence. We tested the hypothesis that telomere length (TL) could predict patient vulnerability and outcome with cancer treatment. Patients and methods An ancillary study in the Elderly Women GINECO Trial 3 was performed to evaluate the impact of geriatric covariates on survival in elderly advanced ovarian cancer patients receiving six cycles of carboplatin. TL was estimated from peripheral blood at inclusion using standard procedures. Results TL (in base pairs) was estimated for 109/111 patients (median 6.1 kb; range [4.5-8.3 kb]). With a cut-off of 5.77 kb, TL discriminated two patient groups, long telomere (LT) and short telomeres (ST), with significantly different treatment completion rates of 0.80 (95%CI [0.71-0.89]) and 0.59 (95%CI [0.41-0.76]), respectively (odds ratio [OR]=2.8, p=0.02). ST patients were at higher risk of serious adverse events (SAE, OR=2.7; p=0.02) and had more unplanned hospital admissions (OR=2.1; p=0.08). After adjustment on FIGO stage, TL shorter than 6 kb was a risk factor of premature death (HR=1.57; p=0.06). Conclusion This exploratory study identifies TL as predictive factor of decreased treatment completion, SAE risk, unplanned hospital admissions and OS after adjustment on FIGO stage. PMID:26638179

Prevention Effects Ameliorate the Prospective Association Between Nonsupportive Parenting and Diminished Telomere Length

PubMed Central

Yu, Tianyi; Beach, Steven R. H.; Philibert, Robert A.

2014-01-01

Telomere length (TL) is an indicator of general systemic aging, with diminished TL associated with several chronic diseases of aging and with heightened mortality risk. Research has begun to focus on the ways in which stress contributes to telomere attrition. The purposes of this study were (a) to establish whether exposure to nonsupportive parenting, defined as high levels of conflict and rancor with low levels of warmth and emotional support, at age 17 would forecast TL 5 years later; and (b) to determine whether participation in an efficacious family-centered prevention program could ameliorate any associations that emerged. Rural African American adolescents participated in the Adults in the Making (AIM) program or a control condition. Primary caregivers provided data on nonsupportive parenting during a pretest when adolescents were age 17. Adolescents provided data on anger at the pretest and at a posttest administered 7 months later. When the youths were age 22, TL was assayed from a blood draw. The results indicated that heightened nonsupportive parenting forecast diminished TL among young adults in the control condition but not among those who participated in AIM; socioeconomic status risk, life stress, and the use of alcohol and cigarettes at age 17, and blood pressure and body mass index at age 22, were controlled. Subsequent exploratory analyses suggested that AIM-induced reductions in adolescents’ anger served as a mediator connecting group assignment to TL. The results suggest that the cellular-level sequelae of nonsupportive parenting and stress are not immutable. PMID:24599483

Leukocyte telomere length correlates with glucose control in adults with recently diagnosed type 2 diabetes.

PubMed

Rosa, Erica Carine Campos Caldas; Dos Santos, Renan Renato Cruz; Fernandes, Luis Fernando Amarante; Neves, Francisco de Assis Rocha; Coelho, Michella Soares; Amato, Angelica Amorim

2018-01-01

We investigated leukocyte relative telomere length (TL) in patients with type 2 diabetes (T2D) diagnosed for no longer than five years and its association with clinical and biochemical variables. Peripheral blood leukocyte relative TL was investigated in 108 patients with T2D (87 women, 21 men) and 125 (37 women, 88 men) age-matched control subjects with normal glucose tolerance, by quantitative polymerase chain reaction. Multiple linear regression analysis was used to examine the association between relative TL and demographic, anthropometric and biochemical indicators of metabolic control among patients with T2D. Patients with T2D had a median time since diagnosis of 1 year and most were on metformin monotherapy, with satisfactory glucose control determined by HbA1c levels. Median relative TL was not different between patients with T2D and control subjects. However, multiple linear regression analyses showed that relative TL was inversely associated with time since T2D diagnosis, fasting plasma glucose levels and HbA1c levels, but not with HbA1c levels assessed in the preceding 5-12 months, after adjustment for age, sex and body mass index. This study suggests that relative TL is not shorter in patients with recently diagnosed T2D, but is inversely correlated with glucose levels, even among patients with overall satisfactory glucose control. Copyright © 2017 Elsevier B.V. All rights reserved.

Laser photogrammetry improves size and demographic estimates for whale sharks

PubMed Central

Richardson, Anthony J.; Prebble, Clare E.M.; Marshall, Andrea D.; Bennett, Michael B.; Weeks, Scarla J.; Cliff, Geremy; Wintner, Sabine P.; Pierce, Simon J.

2015-01-01

Whale sharks Rhincodon typus are globally threatened, but a lack of biological and demographic information hampers an accurate assessment of their vulnerability to further decline or capacity to recover. We used laser photogrammetry at two aggregation sites to obtain more accurate size estimates of free-swimming whale sharks compared to visual estimates, allowing improved estimates of biological parameters. Individual whale sharks ranged from 432–917 cm total length (TL) (mean ± SD = 673 ± 118.8 cm, N = 122) in southern Mozambique and from 420–990 cm TL (mean ± SD = 641 ± 133 cm, N = 46) in Tanzania. By combining measurements of stranded individuals with photogrammetry measurements of free-swimming sharks, we calculated length at 50% maturity for males in Mozambique at 916 cm TL. Repeat measurements of individual whale sharks measured over periods from 347–1,068 days yielded implausible growth rates, suggesting that the growth increment over this period was not large enough to be detected using laser photogrammetry, and that the method is best applied to estimating growth rates over longer (decadal) time periods. The sex ratio of both populations was biased towards males (74% in Mozambique, 89% in Tanzania), the majority of which were immature (98% in Mozambique, 94% in Tanzania). The population structure for these two aggregations was similar to most other documented whale shark aggregations around the world. Information on small (<400 cm) whale sharks, mature individuals, and females in this region is lacking, but necessary to inform conservation initiatives for this globally threatened species. PMID:25870776

Penile Dimensions of Diabetic and Nondiabetic Men With Erectile Dysfunction: A Case-Control Study.

PubMed

Salama, Nader

2018-05-01

This study aimed to report penile dimensions in diabetic and nondiabetic men with erectile dysfunction (ED) and correlate their dimensions with other study variables. A case-control study was designed through retrospective data analysis of diabetic and nondiabetic patients consulting for ED and a control group ( n = 105, each group). Study data retrieved included history, clinical evaluation, and penile dimensions (pendulous length [PL], total length [TL], and circumference [CF]) at flaccid and erect states. Results identified that patients had lower values (mean, cm) for almost all penile dimensions. The diabetic patients identified significant differences in most dimensions, whether in flaccid (PL: 7.46 vs. 7.51 and 7.81, p = .11; TL: 11.8 vs. 12.77 and 12.88, p = .000; CF: 8.84 vs. 9.1 and 9.14, p = .016) or erect state (PL: 9.66 vs. 9.61 and 10, p = .092; TL: 13.96 vs. 14.88 and 15.04, p = .000; CF: 11.56 vs. 12.06 and 11.92, p = .018) as compared with the nondiabetic patients and controls, respectively. No significant correlation was detected between the dimensions and age, durations of diabetes and ED, or erectile function scores. In conclusion, diabetic and nondiabetic patients with ED presented, in varying degrees, significant decline in their penile dimensions, and this was more prevalent in diabetic patients. As changes in penile size could be a silent corollary of comorbidities, monitoring the changes in penile dimensions should be an important component of the clinical checkup of any patient with ED, especially a diabetic patient.

Penile Dimensions of Diabetic and Nondiabetic Men With Erectile Dysfunction: A Case–Control Study

PubMed Central

Salama, Nader

2015-01-01

This study aimed to report penile dimensions in diabetic and nondiabetic men with erectile dysfunction (ED) and correlate their dimensions with other study variables. A case–control study was designed through retrospective data analysis of diabetic and nondiabetic patients consulting for ED and a control group (n = 105, each group). Study data retrieved included history, clinical evaluation, and penile dimensions (pendulous length [PL], total length [TL], and circumference [CF]) at flaccid and erect states. Results identified that patients had lower values (mean, cm) for almost all penile dimensions. The diabetic patients identified significant differences in most dimensions, whether in flaccid (PL: 7.46 vs. 7.51 and 7.81, p = .11; TL: 11.8 vs. 12.77 and 12.88, p = .000; CF: 8.84 vs. 9.1 and 9.14, p = .016) or erect state (PL: 9.66 vs. 9.61 and 10, p = .092; TL: 13.96 vs. 14.88 and 15.04, p = .000; CF: 11.56 vs. 12.06 and 11.92, p = .018) as compared with the nondiabetic patients and controls, respectively. No significant correlation was detected between the dimensions and age, durations of diabetes and ED, or erectile function scores. In conclusion, diabetic and nondiabetic patients with ED presented, in varying degrees, significant decline in their penile dimensions, and this was more prevalent in diabetic patients. As changes in penile size could be a silent corollary of comorbidities, monitoring the changes in penile dimensions should be an important component of the clinical checkup of any patient with ED, especially a diabetic patient. PMID:26130730

Mechanisms of breast cancer risk in shift workers: association of telomere shortening with the duration and intensity of night work.

PubMed

Samulin Erdem, Johanna; Notø, Heidi Ødegaard; Skare, Øivind; Lie, Jenny-Anne S; Petersen-Øverleir, Marte; Reszka, Edyta; Pepłońska, Beata; Zienolddiny, Shanbeh

2017-08-01

Occupational factors such as shiftwork and especially night work that involves disruption of the circadian rhythm may contribute to increased breast cancer risk. Circadian disruption may also affect telomere length (TL). While short TL generally is associated with increased cancer risk, its association with breast cancer risk is inconclusive. We suggest that working schedules might be an important factor in assessment of effects of TL on breast cancer risk. Moreover, telomere shortening might be a potential mechanism for night work-related breast cancer. In this study, effects of shift work on TL and its association with breast cancer risk were investigated in a nested breast cancer case-control study of Norwegian nurses. TL was assessed by qPCR in DNA from 563 breast cancer patients and 619 controls. Here, we demonstrate that TL is affected by intensive night work schedules, as work with six consecutive night for a period of more than 5 years was associated with decreased telomere lengths (-3.18, 95% CI: -6.46 to -0.58, P = 0.016). Furthermore, telomere shortening is associated with increased breast cancer risk in workers with long periods of consecutive night shifts. Thus, nurses with longer telomere lengths had a lower risk for breast cancer if they had worked more than four (OR: 0.37, 95% CI: 0.16-0.79, P = 0.014) or five (OR: 0.31, 95% CI: 0.10-0.83, P = 0.029) consecutive night shifts for a period of 5 years or more. These data suggest that telomere shortening is associated with the duration and intensity of night work and may be a contributing factor for breast cancer risk among female shift workers. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Reproduction and growth of the painted comber Serranus scriba (Serranidae) of the Marine Reserve of Lanzarote Island (Central-Eastern Atlantic)

NASA Astrophysics Data System (ADS)

Tuset, V. M.; García-Díaz, M. M.; González, J. A.; Lorente, M. J.; Lozano, I. J.

2005-08-01

The population biology of painted comber Serranus scriba (Linnaeus, 1758) of the Canary Islands coast was studied to estimate gonad morphology, sexuality, age and growth. Analysis of gonad organization and development revealed that it is a functional simultaneous hermaphrodite. Its anatomy and growth pattern of the reproductive cells is similar to that described in other species of the genus Serranus, although the sequence of vesicles appearing varies during vitellogenesis. Spawning season occurred from January to September with a peak in June. Individuals reached 50% maturity at 17.3 cm TL and 95% at 22.7 cm TL. Length-weight relationship was described by the following parameters: a = 0.01 and b = 3.10, being allometric positive. Age was determined from annuli in whole forming an opaque zone and a translucent zone in each annulus per year. The high percentage of otoliths with translucent zone during the annual cycle indicated that this species presents continuous growth throughout the year. Age range was 2-11 years for fish measuring 15.0-29.4 cm TL. This species is slow-growing and long lived. The growth parameters obtained were L∞ = 34.18 cm TL, k = 0.13 years -1, and to = -2.50 years. Otolith length was the best predictor of fish length, while the otolith weight was the best predictor of age.

Principal component analysis of biometric traits to reveal body confirmation in local hill cattle of Himalayan state of Himachal Pradesh, India.

PubMed

Verma, Deepak; Sankhyan, Varun; Katoch, Sanjeet; Thakur, Yash Pal

2015-12-01

In the present study, biometric traits (body length [BL], heart girth [HG], paunch girth (PG), forelimb length (FLL), hind limb length (HLL), face length, forehead width, forehead length, height at hump, hump length (HL), hook to hook distance, pin to pin distance, tail length (TL), TL up to switch, horn length, horn circumference, and ear length were studied in 218 adult hill cattle of Himachal Pradesh for phenotypic characterization. Morphological and biometrical observations were recorded on 218 hill cattle randomly selected from different districts within the breeding tract. Multivariate statistics and principal component analysis are used to account for the maximum portion of variation present in the original set of variables with a minimum number of composite variables through Statistical software, SAS 9.2. Five components were extracted which accounted for 65.9% of variance. The first component explained general body confirmation and explained 34.7% variation. It was represented by significant loading for BL, HG, PG, FLL, and HLL. Communality estimate ranged from 0.41 (HL) to 0.88 (TL). Second, third, fourth, and fifth component had a high loading for tail characteristics, horn characteristics, facial biometrics, and rear body, respectively. The result of component analysis of biometric traits suggested that indigenous hill cattle of Himachal Pradesh are small and compact size cattle with a medium hump, horizontally placed short ears, and a long tail. The study also revealed that factors extracted from the present investigation could be used in breeding programs with sufficient reduction in the number of biometric traits to be recorded to explain the body confirmation.

Patients with gout have short telomeres compared with healthy participants: association of telomere length with flare frequency and cardiovascular disease in gout.

PubMed

Vazirpanah, N; Kienhorst, L B E; Van Lochem, E; Wichers, C; Rossato, M; Shiels, P G; Dalbeth, N; Stamp, L K; Merriman, T R; Janssen, M; Radstake, T R D J; Broen, J Ca

2017-07-01

Chronic inflammation associates with increased senescence, which is a strong predictor for cardiovascular disease. We hypothesised that inflammation accelerates senescence and thereby enhances the risk of cardiovascular disease in gout. We assessed replicative senescence by quantifying telomere length (TL) in a discovery cohort of 145 Dutch patients with gout and 273 healthy individuals and validated our results in 474 patients with gout and 293 healthy participants from New Zealand. Subsequently, we investigated the effect of cardiovascular disease on TL of all participants. Also, we measured TL of CD4 + and CD8 + T lymphocytes, B lymphocytes, monocytes, natural killer cells and plasmacytoid dendritic cells. Additionally, we assessed the potential temporal difference in TL and telomerase activity. TL in PBMCs of healthy donors decreased over time, reflecting normal ageing. Patients with gout demonstrated shorter telomeres (p=0.001, R 2 =0.01873). In fact, the extent of telomere erosion in patients with gout was higher at any age compared with healthy counterparts at any age (p<0.0001, R 2 =0.02847). Patients with gout with cardiovascular disease had the shortest telomeres and TL was an independent risk factor for cardiovascular disease in patients with gout (p=0.001). TL was inversely associated with the number of gouty flares (p=0.005). Patients with gout have shorter telomeres than healthy participants, reflecting increased cellular senescence. Telomere shortening was associated with the number of flares and with cardiovascular disease in people with gout. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Employment and work schedule are related to telomere length in women

PubMed Central

Parks, C G; DeRoo, L A; Miller, D B; McCanlies, E C; Cawthon, R M; Sandler, D P

2011-01-01

Objectives To examine the association of employment and work schedule with shorter DNA telomeres, a marker of cellular ageing and disease risk factor, and consider whether differences were related to health, behaviours and sociodemographic factors, or varied by stress levels or menopausal status. Methods This cross-sectional analysis of 608 women aged 35–74 in the Sister Study examined determinants of relative telomere length (rTL) measured by quantitative PCR in leucocyte DNA. Age-adjusted regression models estimated base pair (bp) rTL differences for current and lifetime schedule characteristics (ie, part-time, full-time or overtime hours; multiple jobs; irregular hours; shiftwork; work at night). Covariates included race, smoking, perceived stress, sleep, physical activity, health and menopausal status, education, marital status, live births, children under 18, measured body mass index and urinary stress hormones. Results Compared with non-employed women with moderate or substantial past work histories (n=190), those currently working full-time (n=247; median 40 h/week) had a shorter rTL, an age-adjusted difference of −329 bp (95% CI −110 to −548). Longer-duration full-time work was also associated with shorter rTL (age-adjusted difference of −472 bp, 95% CI −786 to −158 for 20+ vs 1–5 years). Findings were not explained by health and demographic covariates. However, rTL differences for working at least full-time were greater in women with higher stress and epinephrine levels. Conclusions Current and long-term full-time work were associated with shorter rTL, with differences of similar magnitude to smoking and history of heart disease or diabetes. Longitudinal data with specific stress measures are needed to further evaluate the impact of work schedule on rTL. PMID:21540175

Employment and work schedule are related to telomere length in women.

PubMed

Parks, C G; DeRoo, L A; Miller, D B; McCanlies, E C; Cawthon, R M; Sandler, D P

2011-08-01

To examine the association of employment and work schedule with shorter DNA telomeres, a marker of cellular ageing and disease risk factor, and consider whether differences were related to health, behaviours and sociodemographic factors, or varied by stress levels or menopausal status. This cross-sectional analysis of 608 women aged 35-74 in the Sister Study examined determinants of relative telomere length (rTL) measured by quantitative PCR in leucocyte DNA. Age-adjusted regression models estimated base pair (bp) rTL differences for current and lifetime schedule characteristics (ie, part-time, full-time or overtime hours; multiple jobs; irregular hours; shiftwork; work at night). Covariates included race, smoking, perceived stress, sleep, physical activity, health and menopausal status, education, marital status, live births, children under 18, measured body mass index and urinary stress hormones. Compared with non-employed women with moderate or substantial past work histories (n=190), those currently working full-time (n=247; median 40 h/week) had a shorter rTL, an age-adjusted difference of -329 bp (95% CI -110 to -548). Longer-duration full-time work was also associated with shorter rTL (age-adjusted difference of -472 bp, 95% CI -786 to -158 for 20+ vs 1-5 years). Findings were not explained by health and demographic covariates. However, rTL differences for working at least full-time were greater in women with higher stress and epinephrine levels. Current and long-term full-time work were associated with shorter rTL, with differences of similar magnitude to smoking and history of heart disease or diabetes. Longitudinal data with specific stress measures are needed to further evaluate the impact of work schedule on rTL.

No Association between Blood Telomere Length and Longitudinally-Assessed Diet or Adiposity in a Young Adult Filipino Population

PubMed Central

Bethancourt, Hilary J.; Kratz, Mario; Beresford, Shirley A. A.; Hayes, M. Geoffrey; Kuzawa, Christopher W.; Duazo, Paulita L.; Borja, Judith B.; Eisenberg, Daniel T. A.

2015-01-01

Purpose Telomeres, DNA-protein structures that cap and protect chromosomes, are thought to shorten more rapidly when exposed to chronic inflammation and oxidative stress. Diet and nutritional status may be a source of inflammation and oxidative stress. However, relationships between telomere length (TL) and diet or adiposity have primarily been studied cross-sectionally among older, overweight/obese populations and yielded inconsistent results. Little is known about the relationship between diet or body composition and TL among younger, low- to normal-weight populations. It also remains unclear how cumulative exposure to a specific diet or body composition during the years of growth and development, when telomere attrition is most rapid, may be related to TL in adulthood. Methods In a sample of 1,459 young adult Filipinos, we assessed the relationship between blood TL at ages 20.8–22.5 and measures of BMI z-score, waist circumference, and diet collected between the ages of 8.5 and 22.5. TL was measured using monochrome multiplex quantitative PCR, and diet was measured using multiple 24-hour recalls. Results We found no associations between blood TL and any of the measures of adiposity or between blood TL and the seven dietary factors examined: processed meats, fried/grilled meats and fish, non-fried fish, coconut oil, fruits and vegetables, bread and bread products, and sugar-sweetened beverages. Conclusions Considering the inconsistencies in the literature and our null results, small differences in body composition and consumption of any single pro- or anti-inflammatory dietary component may not by themselves have a meaningful impact on telomere integrity, or the impact may differ across distinct ecological circumstances. PMID:26497538

No association between blood telomere length and longitudinally assessed diet or adiposity in a young adult Filipino population.

PubMed

Bethancourt, Hilary J; Kratz, Mario; Beresford, Shirley A A; Hayes, M Geoffrey; Kuzawa, Christopher W; Duazo, Paulita L; Borja, Judith B; Eisenberg, Daniel T A

2017-02-01

Telomeres, DNA-protein structures that cap and protect chromosomes, are thought to shorten more rapidly when exposed to chronic inflammation and oxidative stress. Diet and nutritional status may be a source of inflammation and oxidative stress. However, relationships between telomere length (TL) and diet or adiposity have primarily been studied cross-sectionally among older, overweight/obese populations and yielded inconsistent results. Little is known about the relationship between diet or body composition and TL among younger, low- to normal-weight populations. It also remains unclear how cumulative exposure to a specific diet or body composition during the years of growth and development, when telomere attrition is most rapid, may be related to TL in adulthood. In a sample of 1459 young adult Filipinos, we assessed the relationship between blood TL at ages 20.8-22.5 and measures of BMI z-score, waist circumference, and diet collected between the ages of 8.5 and 22.5. TL was measured using monochrome multiplex quantitative PCR, and diet was measured using multiple 24-h recalls. We found no associations between blood TL and any of the measures of adiposity or between blood TL and the seven dietary factors examined: processed meats, fried/grilled meats and fish, non-fried fish, coconut oil, fruits and vegetables, bread and bread products, and sugar-sweetened beverages. Considering the inconsistencies in the literature and our null results, small differences in body composition and consumption of any single pro- or anti-inflammatory dietary component may not by themselves have a meaningful impact on telomere integrity, or the impact may differ across distinct ecological circumstances.

Cellular aging and restorative processes: subjective sleep quality and duration moderate the association between age and telomere length in a sample of middle-aged and older adults.

PubMed

Cribbet, Matthew R; Carlisle, McKenzie; Cawthon, Richard M; Uchino, Bert N; Williams, Paula G; Smith, Timothy W; Gunn, Heather E; Light, Kathleen C

2014-01-01

To examine whether subjective sleep quality and sleep duration moderate the association between age and telomere length (TL). Participants completed a demographic and sleep quality questionnaire, followed by a blood draw. Social Neuroscience Laboratory. One hundred fifty-four middle-aged to older adults (age 45-77 y) participated. Participants were excluded if they were on immunosuppressive treatment and/or had a disease with a clear immunologic (e.g., cancer) component. N/A. Subjective sleep quality and sleep duration were assessed using the Pittsburgh Sleep Quality Index (PSQI) and TL was determined using peripheral blood mononuclear cells (PBMCs). There was a significant first-order negative association between age and TL. Age was also negatively associated with the self-reported sleep quality item and sleep duration component of the PSQI. A significant age × self-reported sleep quality interaction revealed that age was more strongly related to TL among poor sleepers, and that good sleep quality attenuated the association between age and TL. Moreover, adequate subjective sleep duration among older adults (i.e. greater than 7 h per night) was associated with TL comparable to that in middle-aged adults, whereas sleep duration was unrelated to TL for the middle-aged adults in our study. The current study provides evidence for an association between sleep quality, sleep duration, and cellular aging. Among older adults, better subjective sleep quality was associated with the extent of cellular aging, suggesting that sleep duration and sleep quality may be added to a growing list of modifiable behaviors associated with the adverse effects of aging.

Growth and life history variability of the grey reef shark (Carcharhinus amblyrhynchos) across its range

PubMed Central

Bradley, Darcy; Conklin, Eric; Papastamatiou, Yannis P.; McCauley, Douglas J.; Pollock, Kydd; Kendall, Bruce E.; Gaines, Steven D.; Caselle, Jennifer E.

2017-01-01

For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available. Here, we describe the growth, maximum size, sex ratios, size at maturity, and offer a direct estimate of survival of an unfished population of grey reef sharks (Carcharhinus amblyrhynchos) using data from an eight year tag-recapture study. We then synthesized published information on the life history of C. amblyrhynchos from across its geographic range, and for the first time, we attempted to disentangle the contribution of fishing from geographic variation in an elasmobranch species. For Palmyra’s unfished C. amblyrhynchos population, the von Bertalanffy growth function (VBGF) growth coefficient k was 0.05 and asymptotic length L∞ was 163.3 cm total length (TL). Maximum size was 175.5 cm TL from a female shark, length at maturity was estimated at 116.7–123.2 cm TL for male sharks, maximum lifespan estimated from VBGF parameters was 18.1 years for both sexes combined, and annual survival was 0.74 year-1. Consistent with findings from studies on other elasmobranch species, we found significant intraspecific variability in reported life history traits of C. amblyrhynchos. However, contrary to what others have reported, we did not find consistent patterns in life history variability as a function of biogeography or fishing. Ultimately, the substantial, but not yet predictable variability in life history traits observed for C. amblyrhynchos across its geographic range suggests that regional management may be necessary to set sustainable harvest targets and to recover this and other shark species globally. PMID:28207874

Growth and life history variability of the grey reef shark (Carcharhinus amblyrhynchos) across its range.

PubMed

Bradley, Darcy; Conklin, Eric; Papastamatiou, Yannis P; McCauley, Douglas J; Pollock, Kydd; Kendall, Bruce E; Gaines, Steven D; Caselle, Jennifer E

2017-01-01

For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available. Here, we describe the growth, maximum size, sex ratios, size at maturity, and offer a direct estimate of survival of an unfished population of grey reef sharks (Carcharhinus amblyrhynchos) using data from an eight year tag-recapture study. We then synthesized published information on the life history of C. amblyrhynchos from across its geographic range, and for the first time, we attempted to disentangle the contribution of fishing from geographic variation in an elasmobranch species. For Palmyra's unfished C. amblyrhynchos population, the von Bertalanffy growth function (VBGF) growth coefficient k was 0.05 and asymptotic length L∞ was 163.3 cm total length (TL). Maximum size was 175.5 cm TL from a female shark, length at maturity was estimated at 116.7-123.2 cm TL for male sharks, maximum lifespan estimated from VBGF parameters was 18.1 years for both sexes combined, and annual survival was 0.74 year-1. Consistent with findings from studies on other elasmobranch species, we found significant intraspecific variability in reported life history traits of C. amblyrhynchos. However, contrary to what others have reported, we did not find consistent patterns in life history variability as a function of biogeography or fishing. Ultimately, the substantial, but not yet predictable variability in life history traits observed for C. amblyrhynchos across its geographic range suggests that regional management may be necessary to set sustainable harvest targets and to recover this and other shark species globally.

Thermoluminescence (TL) properties and x-ray diffraction (XRD) analysis of high purity CaSO{sub 4}:Dy TL material

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

Kamarudin, Nadira; Abdullah, Wan Saffiey Wan; Dollah, Mohd Taufik

2014-09-03

This paper presents the characterization and TL properties of dysprosium (Dy) doped calcium sulfate (CaSO{sub 4}) TL material produced by co-precipitation technique with 0.5mol% concentration of dopant. The morphology of the produced TL material was studied using scanning electron microscope (SEM) and the micrograph shows that rectangular parallelepiped shaped crystal with the average of 150 μm in length were produced. The crystallinity of the produced powder was studied using x-ray powder diffraction (XRD). The XRD spectra show that the TL material produced is high purity anhydrite CaSO{sub 4} with average crystallite size of 74 nm with orthorhombic crystal system. Themore » TL behavior of produced CaSO{sub 4}:Dy was studied using a TLD reader after exposure to gamma ray by Co{sup 60} source with the doses of 1,5 and 10 Gy. The glow curve shows linear response with glow peak around 230°C which is desired development in the field of radiation dosimetry.« less

TlBr and TlBr xI 1-x crystals for γ-ray detectors

NASA Astrophysics Data System (ADS)

Churilov, Alexei V.; Ciampi, Guido; Kim, Hadong; Higgins, William M.; Cirignano, Leonard J.; Olschner, Fred; Biteman, Viktor; Minchello, Mark; Shah, Kanai S.

2010-04-01

TlBr and TlBr xI 1-x are wide bandgap semiconductor materials being investigated for applications in γ-ray spectroscopy. They have a good combination of density and atomic numbers, promising to make them very efficient detectors. Their low melting points and simple cubic and orthorhombic crystal structures are favorable for bulk crystal growth. However, these semiconductors need to be extremely pure to become useful as radiation detectors. Impurities can lead to charge trapping and scattering, reducing the charge transit lengths and limiting the detector thickness to <1 mm. Additional purification steps were implemented to improve the purity and mobility-lifetime product ( μτ) of electrons. Detector-grade TlBr with the electron μτ product of up to 6×10 -3 cm 2/V has been produced, which allowed operation of detectors up to 15 mm thickness. The ternary TlBr xI 1-x was investigated at different compositions to vary the bandgap and explore the effect of added TlI on the long term stability of detectors. The material analysis and detector characterization results are included.

Diel periodicity and chronology of upstream migration in yellow-phase American eels (Anguilla rostrata)

USGS Publications Warehouse

Aldinger, Joni L.; Welsh, Stuart A.

2017-01-01

Yellow-phase American eel (Anguilla rostrata) upstream migration is temporally punctuated, yet migration chronology within diel time periods is not well-understood. This study examined diel periodicity, chronology, and total length (TL) of six multi-day, high-count (285–1,868 eels) passage events of upstream migrant yellow-phase American eels at the Millville Dam eel ladder, lower Shenandoah River, West Virginia during 2011–2014. We categorized passage by diel periods (vespertine, nocturnal, matutinal, diurnal) and season (spring, summer, late summer/early fall, fall). We depicted passage counts as time-series histograms and used time-series spectral analysis (Fast Fourier Transformation) to identify cyclical patterns and diel periodicity of upstream migration. We created histograms to examine movement patterns within diel periods for each passage event and fit normal mixture models (2–9 mixtures) to describe multiple peaks of passage counts. Periodicity of movements for each passage event followed a 24-h activity cycle with mostly nocturnal movement. Multimodal models were supported by the data; most modes represented nocturnal movements, but modes at or near the transition between twilight and night were also common. We used mixed-model methodology to examine relationships among TL, diel period, and season. An additive-effects model of diel period + season was the best approximating model. A decreasing trend of mean TL occurred across diel movement periods, with the highest mean TL occurring during fall relative to similar mean values of TL for spring, summer, and late summer/early fall. This study increased our understanding of yellow-phase American eels by demonstrating the non-random nature of their upstream migration.

Acculturation Predicts Negative Affect and Shortened Telomere Length.

PubMed

Ruiz, R Jeanne; Trzeciakowski, Jerome; Moore, Tiffany; Ayers, Kimberly S; Pickler, Rita H

2016-10-12

Chronic stress may accelerate cellular aging. Telomeres, protective "caps" at the end of chromosomes, modulate cellular aging and may be good biomarkers for the effects of chronic stress, including that associated with acculturation. The purpose of this analysis was to examine telomere length (TL) in acculturating Hispanic Mexican American women and to determine the associations among TL, acculturation, and psychological factors. As part of a larger cross-sectional study of 516 pregnant Hispanic Mexican American women, we analyzed DNA in blood samples (N = 56) collected at 22-24 weeks gestation for TL as an exploratory measure using monochrome multiplex quantitative telomere polymerase chain reaction (PCR). We measured acculturation with the Acculturation Rating Scale for Mexican Americans, depression with the Beck Depression Inventory, discrimination with the Experiences of Discrimination Scale, and stress with the Perceived Stress Scale. TL was negatively moderately correlated with two variables of acculturation: Anglo orientation and greater acculturation-level scores. We combined these scores for a latent variable, acculturation, and we combined depression, stress, and discrimination scores in another latent variable, "negative affectivity." Acculturation and negative affectivity were bidirectionally correlated. Acculturation significantly negatively predicted TL. Using structural equation modeling, we found the model had an excellent fit with the root mean square error of approximation estimate = .0001, comparative fit index = 1.0, Tucker-Lewis index = 1.0, and standardized root mean square residual = .05. The negative effects of acculturation on the health of Hispanic women have been previously demonstrated. Findings from this analysis suggest a link between acculturation and TL, which may indicate accelerated cellular aging associated with overall poor health outcomes. © The Author(s) 2016.

Histological development of the digestive system of the Amazonian pimelodid catfish Pseudoplatystoma punctifer.

PubMed

Gisbert, E; Moreira, C; Castro-Ruiz, D; Oztürk, S; Fernández, C; Gilles, S; Nuñez, J; Duponchelle, F; Tello, S; Renno, J F; García-Dávila, C; Darias, M J

2014-11-01

The organogenesis of the digestive system was described in the Amazonian pimelodid catfish species Pseudoplatystoma punctifer from hatching (3.5 mm total length, TL) to 41 days post-fertilization (dpf) (58.1 mm TL) reared at 28°C. Newly hatched larvae showed a simple digestive tract, which appeared as a straight undifferentiated and unfolded tube lined by a single layer of columnar epithelial cells (future enterocytes). During the endogenous feeding period, comprised between 20 and 96 h post-fertilization (3.5 to 6.1 mm TL), the larval digestive system experienced a fast transformation with the almost complete development and differentiation of most of digestive organs (buccopahrynx, oesophagus, intestine, liver and exocrine pancreas). Yolk reserves were not completely depleted at the onset of exogenous feeding (4 dpf, 6.1 mm TL), and a period of mixed nutrition was observed up to 6 to 7 dpf (6.8 to 7.3 mm TL) when yolk was definitively exhausted. The stomach was the organ that latest achieved its complete differentiation, characterized by the development of abundant gastric glands in the fundic stomach between 10 and 15 dpf (10.9 to 15.8 mm TL) and the formation of the pyloric sphincter at the junction of the pyloric stomach and the anterior intestine at 15 dpf (15.8 mm TL). The above-mentioned morphological and histological features observed suggested the achievement of a digestive system characteristic of P. punctifer juveniles and adults. The ontogeny of the digestive system in P. punctifer followed the same general pattern as in most Siluriform species so far, although some species-specific differences in the timing of differentiation of several digestive structures were noted, which might be related to different reproductive guilds, egg and larval size or even different larval rearing practices. According to present findings on the histological development of the digestive system in P. punctifer, some recommendations regarding the rearing practices of this species are also provided in order to improve the actual larval rearing techniques of this fast-growing Neotropical catfish species.

The research on the design and performance of 7×1 pump combiners

NASA Astrophysics Data System (ADS)

Cao, Yang; Sheng, Quan; Fu, Shijie; Zhang, Haiwei; Bai, Xiaolei; Shi, Wei; Yao, Jianquan

2018-02-01

The 7×1 end-pumped pump combiners employing 105/125 μm multimode fibers as pump fibers are investigated. Based on the results of our theoretical analysis, sufficient taper length (TL) and low refractive index (RI) of the capillary have been adopted to fabricate high transmission efficiency combiners. A 7×1 end-pumped pump combiner with an average transmission efficiency of 98.9% and a total return loss of 1.1‰ is fabricated in experiments, which could find its application in high-power fiber laser systems.

(Tl, Au)/Si(1 1 1){\\sqrt7 \\times \\sqrt7} 2D compound: an ordered array of identical Au clusters embedded in Tl matrix

NASA Astrophysics Data System (ADS)

Mihalyuk, A. N.; Hsing, C. R.; Wei, C. M.; Eremeev, S. V.; Bondarenko, L. V.; Tupchaya, A. Y.; Gruznev, D. V.; Zotov, A. V.; Saranin, A. A.

2018-01-01

Formation of the highly-ordered \\sqrt7 × \\sqrt7 -periodicity 2D compound has been detected in the (Tl, Au)/Si(1 1 1) system as a result of Au deposition onto the Tl/Si(1 1 1) surface, its composition, structure and electronic properties have been characterized using scanning tunneling microscopy, angle-resolved photoelectron spectroscopy and density-functional-theory calculations. On the basis of these data, the structural model of the Tl-Au compound has been proposed, which adopts 12 Tl atoms and 10 Au atoms (in total, 22 atoms) per \\sqrt7 × \\sqrt7 unit cell, i.e.  ˜1.71 ML of Tl and  ˜1.43 ML of Au (in total, ˜3.14 ML). Qualitatively, the model can be visualized as consisting of truncated-pyramid-like Au clusters with a Tl atom on top, while the other Tl atoms form a double layer around the Au clusters. The (Tl, Au)/Si(1 1 1)\\sqrt7 × \\sqrt7 compound has been found to exhibit pronounced metallic properties at least down to temperatures as low as  ˜25 K, which makes it a promising object for studying electrical transport phenomena in the 2D metallic systems.

Cross-dialectal variation in formant dynamics of American English vowels

PubMed Central

Fox, Robert Allen; Jacewicz, Ewa

2009-01-01

This study aims to characterize the nature of the dynamic spectral change in vowels in three distinct regional varieties of American English spoken in the Western North Carolina, in Central Ohio, and in Southern Wisconsin. The vowels ∕ɪ, ε, e, æ, aɪ∕ were produced by 48 women for a total of 1920 utterances and were contained in words of the structure ∕bVts∕ and ∕bVdz∕ in sentences which elicited nonemphatic and emphatic vowels. Measurements made at the vowel target (i.e., the central 60% of the vowel) produced a set of acoustic parameters which included position and movement in the F1 by F2 space, vowel duration, amount of spectral change [measured as vector length (VL) and trajectory length (TL)], and spectral rate of change. Results revealed expected variation in formant dynamics as a function of phonetic factors (vowel emphasis and consonantal context). However, for each vowel and for each measure employed, dialect was a strong source of variation in vowel-inherent spectral change. In general, the dialect-specific nature and amount of spectral change can be characterized quite effectively by position and movement in the F1 by F2 space, vowel duration, TL (but not VL which underestimates formant movement), and spectral rate of change. PMID:19894839

Short telomeres in hatchling snakes: erythrocyte telomere dynamics and longevity in tropical pythons.

PubMed

Ujvari, Beata; Madsen, Thomas

2009-10-16

Telomere length (TL) has been found to be associated with life span in birds and humans. However, other studies have demonstrated that TL does not affect survival among old humans. Furthermore, replicative senescence has been shown to be induced by changes in the protected status of the telomeres rather than the loss of TL. In the present study we explore whether age- and sex-specific telomere dynamics affect life span in a long-lived snake, the water python (Liasis fuscus). Erythrocyte TL was measured using the Telo TAGGG TL Assay Kit (Roche). In contrast to other vertebrates, TL of hatchling pythons was significantly shorter than that of older snakes. However, during their first year of life hatchling TL increased substantially. While TL of older snakes decreased with age, we did not observe any correlation between TL and age in cross-sectional sampling. In older snakes, female TL was longer than that of males. When using recapture as a proxy for survival, our results do not support that longer telomeres resulted in an increased water python survival/longevity. In fish high telomerase activity has been observed in somatic cells exhibiting high proliferation rates. Hatchling pythons show similar high somatic cell proliferation rates. Thus, the increase in TL of this group may have been caused by increased telomerase activity. In older humans female TL is longer than that of males. This has been suggested to be caused by high estrogen levels that stimulate increased telomerase activity. Thus, high estrogen levels may also have caused the longer telomeres in female pythons. The lack of correlation between TL and age among old snakes and the fact that longer telomeres did not appear to affect python survival do not support that erythrocyte telomere dynamics has a major impact on water python longevity.

Fractional distribution of thallium in paddy soil and its bioavailability to rice.

PubMed

Huang, Xuexia; Li, Ning; Wu, Qihang; Long, Jianyou; Luo, Dinggui; Huang, Xiaowu; Li, Dongmei; Zhao, Dongye

2018-02-01

To investigate the bioavailability of thallium (Tl) in soil and rice in a Tl-contaminated area in Guangdong, China, the topsoil and rice samples were collected from 24 sampling sites and analyzed. Moreover, a modified sequential extraction procedure was applied to determine the different Tl fractions in the soil. The mean pH value of the soil samples was 4.50. The total Tl concentration in the paddy soil was about 4-8 times higher than the Canadian guideline value (1mgkg -1 ) for agricultural land uses. The mean ecological risk index of Tl was determined to be 483, indicating that potential hazard of the paddy soil was serious. The mean content of Tl in rice was 1.42mgkg -1 , which exceeded the German maximum permissible level (0.5mgkg -1 ) of Tl in foods and feedstuffs by a factor of nearly 3. The hazard quotient value via rice intake was 57.6, indicating a high potential health risk to the local residents. The distribution of various Tl fractions followed the order of easily reducible fraction (40.3%) > acid exchangeable fraction (30.5%) > residual fraction (23.8%) > oxidizable fraction (5.4%). Correlation analyses showed that the easily reducible fraction correlates positively with the soil Fe and Mn contents, whereas the acid exchangeable fraction is significantly correlated with the S content. The soil pH was negatively correlated with the Tl content in both soil and rice. The Tl content in rice was more strongly correlated with the exchangeable fraction than the total Tl content in the soil. Overall, the bioavailability of Tl in more acidic soil is higher, and is strongly dependent on the speciation of Tl, especially the content of acid exchangeable fraction. Copyright © 2017 Elsevier Inc. All rights reserved.

Variable growth and longevity of yellow bullhead (Ameiurus natalis) in the Everglades of south Florida, USA

USGS Publications Warehouse

Murie, D.J.; Parkyn, D.C.; Loftus, W.F.; Nico, L.G.

2009-01-01

Yellow bullhead (Ictaluridae: Ameiurus natalis) is the most abundant ictalurid catfish in the Everglades of southern Florida, USA, and, as both prey and predator, is one of many essential components in the ecological-simulation models used in assessing restoration success in the Everglades. Little is known of its biology and life history in this southernmost portion of its native range; the present study provides the first estimates of age and growth from the Everglades. In total, 144 yellow bullheads of 97-312 mm total length (TL) were collected from canals and marshes of the Everglades between April 2000 and January 2001, and from October 2003 to February 2005. Fish were aged using cross-sections of pectoral spines and ranged from 1-12 years, with the maximum age almost twice that of any yellow bullhead previously reported. Yellow bullheads from south Florida grew relatively rapidly during their first 3 years, but after age 5 growth slowed and fish approached an asymptote of ???214 mm TL. Compared to other populations in the United States, yellow bullhead in the Everglades grew relatively slowly, were smaller at age overall, but survived to older ages. ?? 2009 Blackwell Verlag GmbH.

Kinetics of Schottky defect formation and annihilation in single crystal TlBr.

PubMed

Bishop, Sean R; Tuller, Harry L; Kuhn, Melanie; Ciampi, Guido; Higgins, William; Shah, Kanai S

2013-07-28

The kinetics for Schottky defect (Tl and Br vacancy pair) formation and annihilation in ionically conducting TlBr are characterized through a temperature induced conductivity relaxation technique. Near room temperature, defect generation-annihilation was found to take on the order of hours before equilibrium was reached after a step change in temperature, and that mechanical damage imparted on the sample rapidly increases this rate. The rate limiting step to Schottky defect formation-annihilation is identified as being the migration of lower mobility Tl (versus Br), with an estimate for source-sink density derived from calculated diffusion lengths. This study represents one of the first investigations of Schottky defect generation-annihilation kinetics and demonstrates its utility in quantifying detrimental mechanical damage in radiation detector materials.

Telomere length and somatic mutations in correlation with response to immunosuppressive treatment in aplastic anaemia.

PubMed

Park, Hee S; Park, Si N; Im, Kyongok; Kim, Sung-Min; Kim, Jung-Ah; Hwang, Sang M; Lee, Dong S

2017-08-01

We investigated the frequencies of cytogenetic aberrations and somatic mutations of prognostic relevance in 393 patients with aplastic anaemia (AA). Clonality was determined by G-banding/fluorescence in situ hybridization (FISH) (n = 245), and targeted capture sequencing was performed for 88 haematopoiesis-related genes (n = 70). The telomere length (TL) of bone marrow nucleated cells was measured at the single cell level by FISH (n = 135). Eighteen (4·6%) patients showed disease progression, and monosomy 7 (50·0%) was the most predominant cytogenetic evolution at disease transformation. One third of patients (32·9%) presented at least 1 mutation; the most frequently mutated genes were NOTCH1, NF1, SCRIB, BCOR and DNMT3A. The patient group with clonal changes (30·7%) showed an adverse response to immunosuppressive treatment (IST), compared to the non-clonal group, but this finding did not show statistical significance. The TL of AA patients was significantly shorter than normal control and patients with clonal changes showed significantly shorter TLs. Patients with TL>5·9 showed a higher response rate to IST (P = 0·048). In conclusion, the patients with clonal changes or TL attrition showed a poor response to IST. Shorter TL can be used not only as a biomarker, but also as a predictive marker for treatment response to IST. © 2017 John Wiley & Sons Ltd.

Leukocyte Telomere Length in Alzheimer's Disease Patients with a Different Rate of Progression.

PubMed

Tedone, Enzo; Arosio, Beatrice; Colombo, Federico; Ferri, Evelyn; Asselineau, Delphine; Piette, Francois; Gussago, Cristina; Belmin, Joel; Pariel, Sylvie; Benlhassan, Khadija; Casati, Martina; Bornand, Anne; Rossi, Paolo Dionigi; Mazzola, Paolo; Annoni, Giorgio; Doulazmi, Mohamed; Mariani, Jean; Porretti, Laura; Bray, Dorothy H; Mari, Daniela

2015-01-01

Age and short leukocyte telomeres have been associated with a higher risk of Alzheimer's disease (AD). Inflammation is involved in AD and it is suggested that anti-inflammatory interleukin-10 (IL-10) may partly antagonize these processes. The aim is to correlate telomere length (TL) in peripheral blood mononuclear cells (PBMC) from patients with AD to disease progression rate. Moreover, we evaluated whether TL was associated with IL-10 production by unstimulated or amyloid-β (Aβ)-stimulated PBMC. We enrolled 31 late-onset AD and 20 age-matched healthy elderly (HE). After a two-year follow-up period, patients were retrospectively evaluated as slow-progressing (ADS) (Mini Mental State Examination (MMSE) decline over the two years of follow-up ≤3 points) or fast progressing AD (ADF) (MMSE decline ≥5 points). TL was measured by flow cytometry and in vitro IL-10 production by enzyme-linked immunosorbent assay. TL (mean±SD) for HE, ADS, and ADF was 2.3±0.1, 2.0±0.1, and 2.5±0.1 Kb, respectively. ADS showed a shorter TL compared to HE (p = 0.034) and to ADF (p = 0.005). MMSE decline correlated with TL in AD (R2 = 0.284; p = 0.008). We found a significant difference in IL-10 production between unstimulated and Aβ-stimulated PBMC from ADS (40.7±13.7 versus 59.0±27.0; p = 0.004) but not from ADF (39.7±14.4 versus 42.2±22.4). HE showed a trend toward significance (47.1±25.4 versus 55.3±27.9; p = 0.10). PBMC from ADF may be characterized by an impaired response induced by Aβ and by a reduced proliferative response responsible for the longer telomeres. TL might be a contributing factor in predicting the rate of AD progression.

Telomere length and procedural justice predict stress reactivity responses to unfair outcomes in African Americans.

PubMed

Lucas, Todd; Pierce, Jennifer; Lumley, Mark A; Granger, Douglas A; Lin, Jue; Epel, Elissa S

2017-12-01

This experiment demonstrates that chromosomal telomere length (TL) moderates response to injustice among African Americans. Based on worldview verification theory - an emerging psychosocial framework for understanding stress - we predicted that acute stress responses would be most pronounced when individual-level expectancies for justice were discordant with justice experiences. Healthy African Americans (N=118; 30% male; M age=31.63years) provided dried blood spot samples that were assayed for TL, and completed a social-evaluative stressor task during which high versus low levels of distributive (outcome) and procedural (decision process) justice were simultaneously manipulated. African Americans with longer telomeres appeared more resilient (in emotional and neuroendocrine response-higher DHEAs:cortisol) to receiving an unfair outcome when a fair decision process was used, whereas African Americans with shorter telomeres appeared more resilient when an unfair decision process was used. TL may indicate personal histories of adversity and associated stress-related expectancies that influence responses to injustice. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pretherapeutic FDG-PET total metabolic tumor volume predicts response to induction therapy in pediatric Hodgkin's lymphoma.

PubMed

Rogasch, Julian M M; Hundsdoerfer, Patrick; Hofheinz, Frank; Wedel, Florian; Schatka, Imke; Amthauer, Holger; Furth, Christian

2018-05-03

Standardized treatment in pediatric patients with Hodgkin's lymphoma (HL) follows risk stratification by tumor stage, erythrocyte sedimentation rate and tumor bulk. We aimed to identify quantitative parameters from pretherapeutic FDG-PET to assist prediction of response to induction chemotherapy. Retrospective analysis in 50 children with HL (f:18; m:32; median age, 14.8 [4-18] a) consecutively treated according to EuroNet-PHL-C1 (n = 42) or -C2 treatment protocol (n = 8). Total metabolic tumor volume (MTV) in pretherapeutic FDG-PET was defined using a semi-automated, background-adapted threshold. Metabolic (SUVmax, SUVmean, SUVpeak, total lesion glycolysis [MTV*SUVmean]) and heterogeneity parameters (asphericity [ASP], entropy, contrast, local homogeneity, energy, and cumulative SUV-volume histograms) were derived. Early response assessment (ERA) was performed after 2 cycles of induction chemotherapy according to treatment protocol and verified by reference rating. Prediction of inadequate response (IR) in ERA was based on ROC analysis separated by stage I/II (1 and 26 patients) and stage III/IV disease (7 and 16 patients) or treatment group/level (TG/TL) 1 to 3. IR was seen in 28/50 patients (TG/TL 1, 6/12 patients; TG/TL 2, 10/17; TG/TL 3, 12/21). Among all PET parameters, MTV best predicted IR; ASP was the best heterogeneity parameter. AUC of MTV was 0.84 (95%-confidence interval, 0.69-0.99) in stage I/II and 0.86 (0.7-1.0) in stage III/IV. In patients of TG/TL 1, AUC of MTV was 0.92 (0.74-1.0); in TG/TL 2 0.71 (0.44-0.99), and in TG/TL 3 0.85 (0.69-1.0). Patients with high vs. low MTV had IR in 86 vs. 0% in TG/TL 1, 80 vs. 29% in TG/TL 2, and 90 vs. 27% in TG/TL 3 (cut-off, > 80 ml, > 160 ml, > 410 ml). In this explorative study, high total MTV best predicted inadequate response to induction therapy in pediatric HL of all pretherapeutic FDG-PET parameters - in both low and high stages as well as the 3 different TG/TL. Ethics committee number: EA2/151/16 (retrospectively registered).

Thermoluminescence of nanocrystalline CaSO{sub 4}: Dy for gamma dosimetry and calculation of trapping parameters using deconvolution method

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

Mandlik, Nandkumar, E-mail: ntmandlik@gmail.com; Patil, B. J.; Bhoraskar, V. N.

2014-04-24

Nanorods of CaSO{sub 4}: Dy having diameter 20 nm and length 200 nm have been synthesized by the chemical coprecipitation method. These samples were irradiated with gamma radiation for the dose varying from 0.1 Gy to 50 kGy and their TL characteristics have been studied. TL dose response shows a linear behavior up to 5 kGy and further saturates with increase in the dose. A Computerized Glow Curve Deconvolution (CGCD) program was used for the analysis of TL glow curves. Trapping parameters for various peaks have been calculated by using CGCD program.

Thermoluminescence of nanocrystalline CaSO4: Dy for gamma dosimetry and calculation of trapping parameters using deconvolution method

NASA Astrophysics Data System (ADS)

Mandlik, Nandkumar; Patil, B. J.; Bhoraskar, V. N.; Sahare, P. D.; Dhole, S. D.

2014-04-01

Nanorods of CaSO4: Dy having diameter 20 nm and length 200 nm have been synthesized by the chemical coprecipitation method. These samples were irradiated with gamma radiation for the dose varying from 0.1 Gy to 50 kGy and their TL characteristics have been studied. TL dose response shows a linear behavior up to 5 kGy and further saturates with increase in the dose. A Computerized Glow Curve Deconvolution (CGCD) program was used for the analysis of TL glow curves. Trapping parameters for various peaks have been calculated by using CGCD program.

Emergence, development, and maturity of the gonad of two species of chitons "sea cockroach" (Mollusca: Polyplacophora) through the early life stages.

PubMed

Avila-Poveda, Omar Hernando; Abadia-Chanona, Quetzalli Yasú

2013-01-01

This study describes and recognises, using histological and microscopical examinations on a morphometrical basis, several gonad traits through the early life stages of Chiton articulatus and C. albolineatus. Gonadal ontogenesis, gonad development stages, sexual differentiation, onset of the first sexual maturity, and growth sequences or "early life stages" were determined. In addition, allometry between lengths and body weight pooled for both sexes per each chiton were calculated using equation Y = aX(b) . A total of 125 chitons (4≤TL≤40 mm, in total length "TL") were used. All allometric relations showed a strong positive correlation (r), close to 1, with b-values above three, indicating an isometric growth. Gonadal ontogenesis and gonad development stages were categorised into three periods ("Pw" without gonad, "Pe" gonad emergence, and "Pf" gonadal sac formed) and four stages ("S0" gametocytogenesis, "S1" gametogenesis, "S2" mature, and "S3" spawning), respectively. Compound digital images were attained for each process. Periods and stages are overlapped among them and between species, with the following overall confidence intervals in TL: Pw 6.13-14.32 mm, Pe 10.32-16.93 mm, Pf 12.99-25.01 mm, S0 16.08-24.34 mm (females) and 19.51-26.60 mm (males), S1 27.15-35.63 mm (females) and 23.45-32.27 mm (males), S2 24.48-40.24 mm (females) and 25.45-32.87 mm (males). Sexual differentiation (in S0) of both chitons occurs first as a female then as a male; although, males reach the onset of the first sexual maturity earlier than females, thus for C. articulatus males at 17 mm and females at 32 mm, and for C. albolineatus males at 23.5 mm and females at 28 mm, all in TL. Four early life stages (i.e., subjuvenile, juvenile, subadult, and adult) are described and proposed to distinguish growth sequences. Our results may be useful to diverse disciplines, from developmental biology to fisheries management.

Shaping long-term primate development: Telomere length trajectory as an indicator of early maternal maltreatment and predictor of future physiologic regulation.

PubMed

Drury, Stacy S; Howell, Brittany R; Jones, Christopher; Esteves, Kyle; Morin, Elyse; Schlesinger, Reid; Meyer, Jerrold S; Baker, Kate; Sanchez, Mar M

2017-12-01

The molecular, neurobiological, and physical health impacts of child maltreatment are well established, yet mechanistic pathways remain inadequately defined. Telomere length (TL) decline is an emerging molecular indicator of stress exposure with definitive links to negative health outcomes in maltreated individuals. The multiple confounders endemic to human maltreatment research impede the identification of causal pathways. This study leverages a unique randomized, cross-foster, study design in a naturalistic translational nonhuman primate model of infant maltreatment. At birth, newborn macaques were randomly assigned to either a maltreating or a competent control mother, balancing for sex, biological mother parenting history, and social rank. Offspring TL was measured longitudinally across the first 6 months of life (infancy) from peripheral blood. Hair cortisol accumulation was also determined at 6, 12, and 18 months of age. TL decline was greater in animals randomized to maltreatment, but also interacted with biological mother group. Shorter TL at 6 months was associated with higher mean cortisol levels through 18 months (juvenile period) when controlling for relevant covariates. These results suggest that even under the equivalent social, nutritional, and environmental conditions feasible in naturalistic translational nonhuman primate models, early adverse caregiving results in lasting molecular scars that foreshadow elevated health risk and physiologic dysregulation.

Partial supraspinatus tears are associated with tendon lengthening.

PubMed

Farshad-Amacker, Nadja A; Buck, Florian M; Farshad, Mazda; Pfirrmann, Christian W A; Gerber, Christian

2015-02-01

Tendon tear may result in muscular retraction with the loss of contractile amplitude and strength of the rotator cuff muscles. Currently, neither a validated method of measuring supraspinatus tendon length nor normal values are known. It was therefore the purpose of this study to measure the normal length of the supraspinatus tendon and to determine whether partial tears are associated with changes in tendon length. MR examinations of 49 asymptomatic volunteers and 37 patients with arthroscopically proven, isolated partial tears of the supraspinatus tendon were compared. The ratio of the extramuscular tendon length to the distance between the footprint and the glenoid surface was calculated (TL/FG ratio). Tendon length measurements were taken by two independent readers at the bursal and articular surfaces at the anterior, the central and the posterior parts of the tendon. TL/FG ratios at the bursal surface of tendons with partial tears were significantly higher than those in the control group [anterior: 0.78 ± 0.20 vs. 0.66 ± 0.15 (p < 0.05); central: 0.61 ± 0.13 vs. 0.52 ± 0.10 (p < 0.05); posterior: 0.57 ± 0.15 vs. 0.52 ± 0.10 (p < 0.05)]. At the articular surface, differences were significant only anteriorly [0.60 ± 0.13, vs. 0.54 ± 0.10 (p < 0.05)]. A cut-off TL/FG ratio of 0.63 for measurements at the bursal surface in the center of the tendon achieved a sensitivity of 46 % and a specificity of 92 % for the identification of partial cuff tearing. A reproducible method for measurement of extramuscular supraspinatus tendon length is described. Partial tearing of the supraspinatus tendon is associated with significant tendon lengthening, suggesting failure in continuity, and this is most reliably measured on the bursal surface. III.

Structural Basis for Carbohydrate Recognition and Anti-inflammatory Modulation by Gastrointestinal Nematode Parasite Toxascaris leonina Galectin*

PubMed Central

Hwang, Eun Young; Jeong, Mi Suk; Park, Sang Kyun; Ha, Sung Chul; Yu, Hak Sun; Jang, Se Bok

2016-01-01

Toxascaris leonina galectin (Tl-gal) is a galectin-9 homologue protein isolated from an adult worm of the canine gastrointestinal nematode parasite, and Tl-gal-vaccinated challenge can inhibit inflammation in inflammatory bowel disease-induced mice. We determined the first X-ray structures of full-length Tl-gal complexes with carbohydrates (lactose, N-acetyllactosamine, lacto-N-tetraose, sialyllactose, and glucose). Bonds were formed on concave surfaces of both carbohydrate recognition domains (CRDs) in Tl-gal. All binding sites were found in the HXXXR and WGXEER motifs. Charged Arg61/Arg196 and Glu80/Glu215 on the conserved motif of Tl-gal N-terminal CRD and C-terminal CRD are critical amino acids for recognizing carbohydrate binding, and the residues can affect protein folding and structure. The polar amino acids His, Asn, and Trp are also important residues for the interaction with carbohydrates through hydrogen bonding. Hemagglutination activities of Tl-gal were inhibited by interactions with carbohydrates and mutations. We found that the mutation of Tl-gal (E80A/E215A) at the carbohydrate binding region induced protein aggregation and could be caused in many diseases. The short linker region between the N-terminal and C-terminal CRDs of Tl-gal was very stable against proteolysis and maintained its biological activity. This structural information is expected to elucidate the carbohydrate recognition mechanism of Tl-gal and improve our understanding of anti-inflammatory mediators and modulators of immune response. PMID:27742836

The Same Story or a Unique Novel? Within-Participant Principle Component Analysis of Training Load Measures in Professional Rugby Union Skills Training.

PubMed

Weaving, Dan; Dalton, Nicholas E; Black, Christopher; Darrall-Jones, Joshua; Phibbs, Padraic J; Gray, Michael; Jones, Ben; Roe, Gregory A B

2018-03-27

The study aimed to identify which combination of external and internal training load (TL) metrics capture similar or unique information for individual professional players during skills training in rugby union using principal component analysis (PCA). TL data were collected from twenty-one male professional rugby union players across a competitive season. This included PlayerLoad™, total distance (TD), and individualised high-speed distance (HSD; >61% maximal velocity; all external TL) obtained from a micro-technology device worn by each player (Optimeye X4, Catapult Innovations, Melbourne, Australia) and the session-rating of perceived exertion (sRPE; internal TL). PCA was conducted on each individual to extract the underlying combinations of the four TL measures that best describe the total information (variance) provided by the measures. TL measures with PC "loadings" (PC L ) above 0.7 were deemed to possess well-defined relationships with the extracted PC. The findings show that from the four TL measures, the majority of an individual's TL information (1 st PC: 55 to 70%) during skills training can be explained by either sRPE (PC L : 0.72 to 0.95), TD (PC L : 0.86 to 0.98) or PlayerLoad™ (PC L : 0.71 to 0.98). HSD was the only variable to relate to the 2nd PC (PC L : 0.72 to 1.00), which captured additional TL information (+19 to 28%). Findings suggest practitioners could quantify the TL of rugby union skills training with one of PlayerLoad™, TD, or sRPE plus HSD whilst limiting omitted information of the TL imposed during professional rugby union skills training.

Gender differences in normal left ventricle of adult FVB/N mice due to variation in interleukins and natriuretic peptides expression levels.

PubMed

Haroon, Javeria; Foureaux, Giselle; Martins, Almir S; Ferreira, Anderson J; Reis, Adelina M; Javed, Qamar

2015-01-01

This study examined the sex differences for physical, morphological, histological, mRNA, and protein expression levels changes for interleukins and natriuretic peptides in left ventricle (LV) of two groups of adult FVB/N mice; males (WM) and females (WF). LV morphological, histological, reverse transcription and quantitative real-time PCR (RT-PCR), and immunohistochemical (IHC) alterations were determined in FVB/N mice at 34-35 weeks on gender basis. Confirming the gender dimorphism, FVB/N males (WM) illustrated a significant reduction in ANP and IL1-A levels as well as significantly increased body weight (BW (gm)), tibia length (TL (mm)), heart weight (HW (mg)), heart weight-to-body weight (HW/BW (mg/gm)) ratio, heart weight-to-tibia length (HW/TL (mg/mm)) ratio, left ventricle weight (LV (mg)), left ventricle-to-body weight (LV/BW (mg/gm)) ratio, and left ventricle-to-tibia length (LV/TL (mg/mm)) ratio, left ventricular (LV) cardiomyocyte diameter, high BNP, NPRA, IL-1B, and IL1R1 expression in comparison with FVB/N females (WF). Gender differences in relation to left ventricle (LV) may be due to differences in the interleukins and natriuretic peptides levels as an outcome of sex related hormones. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gonad development during the early life of Octopus maya (Mollusca: Cephalopoda).

PubMed

Avila-Poveda, Omar Hernando; Colin-Flores, Rafael Francisco; Rosas, Carlos

2009-02-01

Gonad development during the early life of Octopus maya is described in terms of histological, morphometric, oocytes growth, and somatic-oocyte relationship data obtained from octopus cultured at the UMDI-UNAM, in Sisal, Yucatan, Mexico. This study is the first publication on gonad development during the early life of Octopus maya. A total of 83 O. maya specimens were used; their sizes ranged from 6.5 to 76 mm of total length (TL), 4 to 28 mm of dorsal mantle length (DML), 2.5 to 20 mm of ventral mantle length (VML), and 0.0180 to 7.2940 g of fixed body weight (fBW). Animals were weighed and measured only after preservation. A loss of 10% of living weight was estimated for juvenile octopuses after formalin preservation. The relation of length to weight (VML, DML, TL/fBW) pooled for both sexes had a strong positive correlation (r), as shown by a potential power function that was quite close to 1. Compound images were produced from numerous microscopic fields. The histological examination revealed that, 4 months after hatching, male octopus (24.5 mm DML and 7.2940 g fBW) were in gonad stages 2 (maturing) to 3 (mature), with spermatogonia and spermatocytes in the tubule wall and abundant spermatids and spermatozoa in the central lumen of the seminiferous tubules, suggesting the occurrence of different phases of gonad development at different maturity stages. In contrast, females (22.5 mm DML and 4.8210 g fBW) at the same time since hatching were immature (stage 1), with many oogonia, few oocytes, and germinal epithelium. This suggests that males reach maturity earlier than females, indicating a probable onset of maturity for males at around 4 months of culture or 8 g of wet body weight. Our results indicate the possibility that the size-at-weight can be recognized early with a degree of certainty that allows the sexes to be separated for culture purposes; but more detailed studies on reproduction in relation to endocrinology and nutrition are needed.

Behavior of White Sturgeon near hydroprojects and fishways

USGS Publications Warehouse

Parsley, M.J.; Wright, C.D.; Van Der Leeuw, B. K.; Kofoot, E.E.; Perry, C.A.; Moser, M.L.

2006-01-01

During March 2004 through November 2005, white sturgeon movements were monitored at The Dalles Dam to characterize their distribution and movements in the immediate vicinity of the dam and to determine timing and routes of passage. A combination of radio and acoustic telemetry technologies were used to detect tagged fish within fishways and at strategic locations along the dam, the shorelines, and in the forebay. White sturgeon > 95 cm total length (TL) that were captured on baited setlines fished in the forebay and in the tailrace cul-de-sac received a surgically implanted transmitter that emitted radio and acoustic signals. During the course of this study, a total of 148 fish were tagged; 58 were captured and released in the forebay and 90 in the tailrace.

Length-weight relationship and a relative condition factor equation for lake sturgeon (Acipenser fulvescens) from the St. Clair River system (Michigan, USA)

USGS Publications Warehouse

Craig, Jaquelyn M.; Thomas, Michael V.; Nichols, Susan Jerrine

2005-01-01

Several USA state, federal, and Canadian agencies study lake sturgeon (Acipenser fulvescens) within the St Clair River and Lake St Clair, collectively referred to hereafter as the St Clair River (SCR) system. Previously, there has been no set standard for determining condition for SCR system lake sturgeon. Condition measures the variation from the expected weight for length as an indicator of fatness, general well-being, gonad development, etc. The aim of this project was to determine the length–weight relationship of lake sturgeon caught from the SCR system, from which a relative condition factor (Kn) equation could be derived. Total length (TL, mm) and weight (W, kg) were measured for 1074 lake sturgeon (101 males and 16 females were identifiable) collected by setline and bottom trawl from the SCR system in May–September, 1997–2002. Analysis of covariance found no difference in the length–weight relationship between sampling gear or sex. Least-squares regression of log10W × log10TL produced the overall equation logW = 3.365logTL − 9.320. Using the exponential form of the slope and y-intercept, relative condition factor for lake sturgeon from the SCR system can be calculated as Kn = W/[(4.786 × 10−10)(TL3.365)]. Equations for males and females were also developed. Overall, body condition was significantly correlated with both age and girth; no significant difference in Kn by sex was found. In general, the SCR lake sturgeon population was near the upper ends of growth and condition ranges listed in the literature, comparable with those populations that are at similar latitudes. Although condition factors should be interpreted with caution, proper use of a standard equation provides a non-lethal measure of overall fish health that can be used by biologists and managers in ongoing efforts to restore lake sturgeon throughout the Great Lakes.

ZResponse to selection, heritability and genetic correlations between body weight and body size in Pacific white shrimp, Litopenaeus vannamei

NASA Astrophysics Data System (ADS)

Andriantahina, Farafidy; Liu, Xiaolin; Huang, Hao; Xiang, Jianhai

2012-03-01

To quantify the response to selection, heritability and genetic correlations between weight and size of Litopenaeus vannamei, the body weight (BW), total length (TL), body length (BL), first abdominal segment depth (FASD), third abdominal segment depth (TASD), first abdominal segment width (FASW), and partial carapace length (PCL) of 5-month-old parents and of offspnng were measured by calculating seven body measunngs of offspnng produced by a nested mating design. Seventeen half-sib families and 42 full-sib families of L. vannamei were produced using artificial fertilization from 2-4 dams by each sire, and measured at around five months post-metamorphosis. The results show that hentabilities among vanous traits were high: 0.515±0.030 for body weight and 0.394±0.030 for total length. After one generation of selection. the selection response was 10.70% for offspring growth. In the 5th month, the realized heritability for weight was 0.296 for the offspnng generation. Genetic correlations between body weight and body size were highly variable. The results indicate that external morphological parameters can be applied dunng breeder selection for enhancing the growth without sacrificing animals for determining the body size and breed ability; and selective breeding can be improved significantly, simultaneously with increased production.

Is the sagittal postural alignment different in normal and dysphonic adult speakers?

PubMed

Franco, Débora; Martins, Fernando; Andrea, Mário; Fragoso, Isabel; Carrão, Luís; Teles, Júlia

2014-07-01

Clinical research in the field of voice disorders, in particular functional dysphonia, has suggested abnormal laryngeal posture due to muscle adaptive changes, although specific evidence regarding body posture has been lacking. The aim of our study was to verify if there were significant differences in sagittal spine alignment between normal (41 subjects) and dysphonic speakers (33 subjects). Cross-sectional study. Seventy-four adults, 35 males and 39 females, were submitted to sagittal plane photographs so that spine alignment could be analyzed through the Digimizer-MedCalc Software Ltd program. Perceptual and acoustic evaluation and nasoendoscopy were used for dysphonic judgments: normal and dysphonic speakers. For thoracic length curvature (TL) and for the kyphosis index (KI), a significant effect of dysphonia was observed with mean TL and KI significantly higher for the dysphonic speakers than for the normal speakers. Concerning the TL variable, a significant effect of sex was found, in which the mean of the TL was higher for males than females. The interaction between dysphonia and sex did not have a significant effect on TL and KI variables. For the lumbar length curvature variable, a significant main effect of sex was demonstrated; there was no significant main effect of dysphonia or significant sex×dysphonia interaction. Findings indicated significant differences in some sagittal spine posture measures between normal and dysphonic speakers. Postural measures can add useful information to voice assessment protocols and should be taken into account when considering particular treatment strategies. Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Leukocyte Telomere Length in the Neonatal Offspring of Mothers with Gestational and Pre-Gestational Diabetes.

PubMed

Gilfillan, Christopher; Naidu, Pratyusha; Gunawan, Florence; Hassan, Fadwa; Tian, Pei; Elwood, Ngaire

2016-01-01

Telomeres undergo shortening with cell division, accelerated by increased oxidative stress. We aimed to demonstrate shortened telomeres in the offspring of mothers who have diabetes as a consequence of exposure to increased oxidative stress during intrauterine development. We examined the level of glycaemia (glucose, HbA1c, fructosamine), oxidative stress (lipid peroxidation) and the levels of antioxidant enzymes (Superoxide dismutase (SOD) and Selenium dependent glutathione peroxidase) and correlate these findings with mean telomere length (TL) in maternal and foetal blood in groups of pregnant women with pre-gestational diabetes (PGD), gestational diabetes (GD) and a euglycaemic control group. Foetal and maternal glucose, maternal HbA1c, and foetal insulin and C-peptide were higher in the PGD group with the GD group being intermediate. Markers of oxidative stress did not vary between groups with the exception of foetal SOD activity that was highest in the GD group. There were no detectable differences in maternal or foetal TL between study groups. An exploratory analysis looking at correlations between glycaemic and oxidative stress parameters and TL revealed a negative correlation between maternal and foetal glucose and TL across the whole study population. This relationship held for the short-term marker of glycaemic control, fructosamine. We were unable to show significant telomere shortening in the offspring of mothers with PGD or GD. Exploratory analysis revealed a relationship between foetal TL and short-term glycaemia particularly in PGD. It is possible that increased telomerase activity can compensate for long-term increased oxidative stress but not for short-term dysglycaemia.

Assessment of nonlethal methods for predicting muscle tissue mercury concentrations in coastal marine fishes

PubMed Central

Piraino, Maria N.; Taylor, David L.

2013-01-01

Caudal fin clips and dorsolateral scales were analyzed in this study as a potential nonlethal approach for predicting muscle tissue mercury (Hg) concentrations in marine fishes. Target fishes were collected from the Narragansett Bay (RI, USA), and included black sea bass Centropristis striata (n = 54, 14–55 cm total length, TL), bluefish Pomatomus saltatrix (n = 113, 31–73 cm TL), striped bass Morone saxatilis (n = 40, 34–102 cm TL), summer flounder Paralichthys dentatus (n = 64, 18–55 cm TL), and tautog Tautoga onitis (n = 102, 27–61 cm TL). For all fish species, Hg concentrations were greatest in muscle tissue (mean muscle Hg = 0.47–1.18 mg/kg dry weight), followed by fin clips (0.03–0.09 mg/kg dry weight) and scales (0.01–0.07 mg/kg dry weight). The coefficient of determination (R2) derived from power regressions of intra-species muscle Hg against fin and scale Hg ranged between 0.35–0.78 (mean R2 = 0.57) and 0.14–0.37 (mean R2 = 0.30), respectively. The inclusion of fish body size interaction effects in the regression models improved the predictive ability of fins (R2 = 0.63–0.80; mean = 0.71) and scales (R2 = 0.33–0.71; mean = 0.53). According to the high level of uncertainty within the regression models (R2 values) and confidence interval widths, scale analysis was deemed an ineffective tool for estimating muscle tissue Hg concentrations in the target species. In contrast, the examination of fin clips as predictors of muscle Hg had value as a cursory screening tool, but this method should not be the foundation for developing human consumption advisories. It is also noteworthy that the efficacy of these nonlethal techniques was highly variable across fishes, and likely depends on species-specific life history characteristics. PMID:23929385

The Thermoluminescence Response of Ge-Doped Flat Fibers to Gamma Radiation

PubMed Central

Mat Nawi, Siti Nurasiah Binti; Wahib, Nor Fadira Binti; Zulkepely, Nurul Najua Binti; Amin, Yusoff Bin Mohd; Min, Ung Ngie; Bradley, David Andrew; Md Nor, Roslan Bin; Maah, Mohd Jamil

2015-01-01

Study has been undertaken of the thermoluminescence (TL) yield of various tailor-made flat cross-section 6 mol% Ge-doped silica fibers, differing only in respect of external dimensions. Key TL dosimetric characteristics have been investigated, including glow curves, dose response, sensitivity, fading and reproducibility. Using a 60Co source, the samples were irradiated to doses within the range 1 to 10 Gy. Prior to irradiation, the flat fibers were sectioned into 6 mm lengths, weighed, and annealed at 400 °C for 1 h. TL readout was by means of a Harshaw Model 3500 TLD reader, with TLD-100 chips (LiF:Mg, Ti) used as a reference dosimeter to allow the relative response of the fibers to be evaluated. The fibers have been found to provide highly linear dose response and excellent reproducibility over the range of doses investigated, demonstrating high potential as TL-mode detectors in radiation medicine applications. Mass for mass, the results show the greatest TL yield to be provided by fibers of the smallest cross-section, analysis indicating this to be due to minimal light loss in transport of the TL through the bulk of the silica medium. PMID:26307987

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.

Stress, depressive status and telomere length: Does social interaction and coping strategy play a mediating role?

PubMed

Liu, Jia Jia; Wei, Ya Bin; Forsell, Yvonne; Lavebratt, Catharina

2017-11-01

Telomeres have been reported to be shorter in individuals exposed to psychosocial stress and in those with depression. Since negative environmental stress is a risk factor for depression, the present study tested whether stressors in childhood (CA) and recent adulthood (NLE) predicted telomere attrition directly and/or indirectly through individuals' depressive status 3-6 years before TL measurement; and then if social interaction and coping strategies in adulthood influenced the relationship between depressive status and TL. Participants were 337 individuals with a recent depression diagnosis and 574 screened controls that derived from a longitudinal population-based cohort study conducted in Stockholm, Sweden. Relative TL was determined using qPCR. Relationships between the key variables stressors, depressive status, social interaction, coping strategies and TL were explored by path analysis in males and females, adjusting for age. The key variables were correlated in expected directions. In females, depressive status and age had direct negative effects on TL (p < 0.05) and both CA (p = 0.025) and NLE (p < 0.003) had indirect negative effects on TL. For males, the effects of stressors and depressive status on TL were mediated by social interaction (p = 0.005) and the coping strategy worry (p = 0.005). In females, no mediation effect of social interaction and coping strategy was detected. Only little of the TL variation was explained by the models. The environmental stress information was limited. Our findings propose gender-specific paths from environmental stressors through depressive status, social interaction and coping strategy to TL. Copyright © 2017 Elsevier B.V. All rights reserved.

Structural Basis for Carbohydrate Recognition and Anti-inflammatory Modulation by Gastrointestinal Nematode Parasite Toxascaris leonina Galectin.

PubMed

Hwang, Eun Young; Jeong, Mi Suk; Park, Sang Kyun; Ha, Sung Chul; Yu, Hak Sun; Jang, Se Bok

2016-12-02

Toxascaris leonina galectin (Tl-gal) is a galectin-9 homologue protein isolated from an adult worm of the canine gastrointestinal nematode parasite, and Tl-gal-vaccinated challenge can inhibit inflammation in inflammatory bowel disease-induced mice. We determined the first X-ray structures of full-length Tl-gal complexes with carbohydrates (lactose, N-acetyllactosamine, lacto-N-tetraose, sialyllactose, and glucose). Bonds were formed on concave surfaces of both carbohydrate recognition domains (CRDs) in Tl-gal. All binding sites were found in the HXXXR and WGXEER motifs. Charged Arg 61 /Arg 196 and Glu 80 /Glu 215 on the conserved motif of Tl-gal N-terminal CRD and C-terminal CRD are critical amino acids for recognizing carbohydrate binding, and the residues can affect protein folding and structure. The polar amino acids His, Asn, and Trp are also important residues for the interaction with carbohydrates through hydrogen bonding. Hemagglutination activities of Tl-gal were inhibited by interactions with carbohydrates and mutations. We found that the mutation of Tl-gal (E80A/E215A) at the carbohydrate binding region induced protein aggregation and could be caused in many diseases. The short linker region between the N-terminal and C-terminal CRDs of Tl-gal was very stable against proteolysis and maintained its biological activity. This structural information is expected to elucidate the carbohydrate recognition mechanism of Tl-gal and improve our understanding of anti-inflammatory mediators and modulators of immune response. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Dipole response of the odd-proton nucleus 205Tl up to the neutron-separation energy

NASA Astrophysics Data System (ADS)

Benouaret, N.; Beller, J.; Pai, H.; Pietralla, N.; Ponomarev, V. Yu; Romig, C.; Schnorrenberger, L.; Zweidinger, M.; Scheck, M.; Isaak, J.; Savran, D.; Sonnabend, K.; Raut, R.; Rusev, G.; Tonchev, A. P.; Tornow, W.; Weller, H. R.; Kelley, J. H.

2016-11-01

The low-lying electromagnetic dipole strength of the odd-proton nuclide 205Tl has been investigated up to the neutron separation energy exploiting the method of nuclear resonance fluorescence. In total, 61 levels of 205Tl have been identified. The measured strength distribution of 205Tl is discussed and compared to those of even-even and even-odd mass nuclei in the same mass region as well as to calculations that have been performed within the quasi-particle phonon model.

Exploring the Hg pollution in global marginal seas by trophic biomagnification in demersal fishes

NASA Astrophysics Data System (ADS)

Tseng, C. M.; Hsieh, Y. C.; Chiang, C. Y.; Lamborg, C. H.; Chang, N. N.; Shiao, J. C.

2017-12-01

Limited knowledge still exists concerning the effects of size composition and trophic level (TL) on mercury levels in the demersal fishes associated with human activities in the marginal seas. In this study, we found evidence of strong control of TL on the Hg in fish and its biomagnification via food webs in the ECS. Total Hg in seven selected fish species, collected during the cruise OR1- 890 in July 2009, ranged from 2.6 and 256.2 ng g-1 (n=72). There were good linear relationships between Hg concentrations and fish body length (R2 = 0.79) and weight (R2 = 0.82), respectively, other than environmental variables (R2 = 0 0.03). It indicates that the Hg concentration in fish is mainly controlled by the growth mechanism of the fish itself through food chain transfer. In order to investigate how Hg levels in fish through trophic magnification associated with environmental changes, we hence developed the empirical method to calculate Hg accumulation rate (MAR) via the relationship of Hg concentration with the fish age for each fish species. The results further showed a significantly positive correlation of MAR with trophic levels, which relationship is Ln MAR =6.1 TL-15.8 (R2 = 0.89) in the ECS shelf. The magnitude of the slope (δMAR/δTL) as a biomagnification index of demersal fish shall provide the feasibility to compare Hg pollution situation among different marine ecosystems. Globally, the biomagnification indicator in the demersal fishes of the ECS is much greater than those in other marginal seas, suggesting high regional Hg pollution impacts from Mainland China.

Measuring telomere length and telomere dynamics in evolutionary biology and ecology

PubMed Central

Nussey, Daniel H; Baird, Duncan; Barrett, Emma; Boner, Winnie; Fairlie, Jennifer; Gemmell, Neil; Hartmann, Nils; Horn, Thorsten; Haussmann, Mark; Olsson, Mats; Turbill, Chris; Verhulst, Simon; Zahn, Sandrine; Monaghan, Pat

2014-01-01

Telomeres play a fundamental role in the protection of chromosomal DNA and in the regulation of cellular senescence. Recent work in human epidemiology and evolutionary ecology suggests adult telomere length (TL) may reflect past physiological stress and predict subsequent morbidity and mortality, independent of chronological age. Several different methods have been developed to measure TL, each offering its own technical challenges. The aim of this review is to provide an overview of the advantages and drawbacks of each method for researchers, with a particular focus on issues that are likely to face ecologists and evolutionary biologists collecting samples in the field or in organisms that may never have been studied in this context before. We discuss the key issues to consider and wherever possible try to provide current consensus view regarding best practice with regard to sample collection and storage, DNA extraction and storage, and the five main methods currently available to measure TL. Decisions regarding which tissues to sample, how to store them, how to extract DNA, and which TL measurement method to use cannot be prescribed, and are dependent on the biological question addressed and the constraints imposed by the study system. What is essential for future studies of telomere dynamics in evolution and ecology is that researchers publish full details of their methods and the quality control thresholds they employ. PMID:25834722

Overexpression of the AtSHI Gene in Poinsettia, Euphorbia pulcherrima, Results in Compact Plants

PubMed Central

Islam, M. Ashraful; Lütken, Henrik; Haugslien, Sissel; Blystad, Dag-Ragnar; Torre, Sissel; Rolcik, Jakub; Rasmussen, Søren K.; Olsen, Jorunn E.; Clarke, Jihong Liu

2013-01-01

Euphorbia pulcherrima, poinsettia, is a non-food and non-feed vegetatively propagated ornamental plant. Appropriate plant height is one of the most important traits in poinsettia production and is commonly achieved by application of chemical growth retardants. To produce compact poinsettia plants with desirable height and reduce the utilization of growth retardants, the Arabidopsis SHORT INTERNODE (AtSHI) gene controlled by the cauliflower mosaic virus 35S promoter was introduced into poinsettia by Agrobacterium-mediated transformation. Three independent transgenic lines were produced and stable integration of transgene was verified by PCR and Southern blot analysis. Reduced plant height (21–52%) and internode lengths (31–49%) were obtained in the transgenic lines compared to control plants. This correlates positively with the AtSHI transcript levels, with the highest levels in the most dwarfed transgenic line (TL1). The indole-3-acetic acid (IAA) content appeared lower (11–31% reduction) in the transgenic lines compared to the wild type (WT) controls, with the lowest level (31% reduction) in TL1. Total internode numbers, bract numbers and bract area were significantly reduced in all transgenic lines in comparison with the WT controls. Only TL1 showed significantly lower plant diameter, total leaf area and total dry weight, whereas none of the AtSHI expressing lines showed altered timing of flower initiation, cyathia abscission or bract necrosis. This study demonstrated that introduction of the AtSHI gene into poinsettia by genetic engineering can be an effective approach in controlling plant height without negatively affecting flowering time. This can help to reduce or avoid the use of toxic growth retardants of environmental and human health concern. This is the first report that AtSHI gene was overexpressed in poinsettia and transgenic poinsettia plants with compact growth were produced. PMID:23308204

Longitudinal changes in telomere length and associated genetic parameters in dairy cattle analysed using random regression models.

PubMed

Seeker, Luise A; Ilska, Joanna J; Psifidi, Androniki; Wilbourn, Rachael V; Underwood, Sarah L; Fairlie, Jennifer; Holland, Rebecca; Froy, Hannah; Bagnall, Ainsley; Whitelaw, Bruce; Coffey, Mike; Nussey, Daniel H; Banos, Georgios

2018-01-01

Telomeres cap the ends of linear chromosomes and shorten with age in many organisms. In humans short telomeres have been linked to morbidity and mortality. With the accumulation of longitudinal datasets the focus shifts from investigating telomere length (TL) to exploring TL change within individuals over time. Some studies indicate that the speed of telomere attrition is predictive of future disease. The objectives of the present study were to 1) characterize the change in bovine relative leukocyte TL (RLTL) across the lifetime in Holstein Friesian dairy cattle, 2) estimate genetic parameters of RLTL over time and 3) investigate the association of differences in individual RLTL profiles with productive lifespan. RLTL measurements were analysed using Legendre polynomials in a random regression model to describe TL profiles and genetic variance over age. The analyses were based on 1,328 repeated RLTL measurements of 308 female Holstein Friesian dairy cattle. A quadratic Legendre polynomial was fitted to the fixed effect of age in months and to the random effect of the animal identity. Changes in RLTL, heritability and within-trait genetic correlation along the age trajectory were calculated and illustrated. At a population level, the relationship between RLTL and age was described by a positive quadratic function. Individuals varied significantly regarding the direction and amount of RLTL change over life. The heritability of RLTL ranged from 0.36 to 0.47 (SE = 0.05-0.08) and remained statistically unchanged over time. The genetic correlation of RLTL at birth with measurements later in life decreased with the time interval between samplings from near unity to 0.69, indicating that TL later in life might be regulated by different genes than TL early in life. Even though animals differed in their RLTL profiles significantly, those differences were not correlated with productive lifespan (p = 0.954).

Longitudinal changes in telomere length and associated genetic parameters in dairy cattle analysed using random regression models

PubMed Central

Ilska, Joanna J.; Psifidi, Androniki; Wilbourn, Rachael V.; Underwood, Sarah L.; Fairlie, Jennifer; Holland, Rebecca; Froy, Hannah; Bagnall, Ainsley; Whitelaw, Bruce; Coffey, Mike; Nussey, Daniel H.; Banos, Georgios

2018-01-01

Telomeres cap the ends of linear chromosomes and shorten with age in many organisms. In humans short telomeres have been linked to morbidity and mortality. With the accumulation of longitudinal datasets the focus shifts from investigating telomere length (TL) to exploring TL change within individuals over time. Some studies indicate that the speed of telomere attrition is predictive of future disease. The objectives of the present study were to 1) characterize the change in bovine relative leukocyte TL (RLTL) across the lifetime in Holstein Friesian dairy cattle, 2) estimate genetic parameters of RLTL over time and 3) investigate the association of differences in individual RLTL profiles with productive lifespan. RLTL measurements were analysed using Legendre polynomials in a random regression model to describe TL profiles and genetic variance over age. The analyses were based on 1,328 repeated RLTL measurements of 308 female Holstein Friesian dairy cattle. A quadratic Legendre polynomial was fitted to the fixed effect of age in months and to the random effect of the animal identity. Changes in RLTL, heritability and within-trait genetic correlation along the age trajectory were calculated and illustrated. At a population level, the relationship between RLTL and age was described by a positive quadratic function. Individuals varied significantly regarding the direction and amount of RLTL change over life. The heritability of RLTL ranged from 0.36 to 0.47 (SE = 0.05–0.08) and remained statistically unchanged over time. The genetic correlation of RLTL at birth with measurements later in life decreased with the time interval between samplings from near unity to 0.69, indicating that TL later in life might be regulated by different genes than TL early in life. Even though animals differed in their RLTL profiles significantly, those differences were not correlated with productive lifespan (p = 0.954). PMID:29438415

Living with the altered self: a qualitative study of life after total laryngectomy.

PubMed

Bickford, Jane; Coveney, John; Baker, Janet; Hersh, Deborah

2013-06-01

Total laryngectomy (TL), a life-preserving surgery, results in profound physical and communication changes for the individual. Physical and psychosocial adjustment to a TL is complex, and quality-of-life (QoL) measures have provided useful knowledge to assist clinical management. However, many tools were developed without considering the perspectives of people who have experienced TL. To improve understanding of the phenomena of living with TL, a qualitative study was conducted which explored the views and experiences of seven men and five women from a range of ages, geographical locations, and social situations who had undergone a TL. Data were collected through in-depth, semi-structured interviews, journals, and field notes, and analysed using a constructivist grounded theory approach and symbolic interactionism. The emergent concept was identifying with the altered self after TL as reflected in dynamic multi-level changes (physical, communication, and psycho-emotional) continuously interacting with intrinsic and extrinsic interpersonal factors including personal and socio-cultural constructs, e.g., age, gender, resilience, beliefs, and supports. This process affected the strategies these individuals used to negotiate their social experiences. The extent to which communication changes disrupted social roles affecting a person's sense of self appeared to relate to long-term adjustment.

Asymmetries of the central sulcus in young adults: Effects of gender, age and sulcal pattern.

PubMed

Sun, Bo; Ge, Haitao; Tang, Yuchun; Hou, Zhongyu; Xu, Junhai; Lin, Xiangtao; Liu, Shuwei

2015-08-01

In this study, we clarified the gender and age-related asymmetries of the central sulcus (CS) in early adulthood using a parametric ribbon method. The CS was reconstructed and parameterized automatically from 3D MR images of 112 healthy right-handed subjects. The 3D anatomic morphology of the CS was presented using 5 sulcal parameters, including sulcal depth position-based profile (DPP), average depth (AD), average width (AW), top length (TL) and bottom length (BL). Asymmetry differences in DPPs were found in the medial and lateral part of the CS. In addition, significant gender differences were observed in the medial and middle parts of the right CS DPPs but scattered in the left side. We found leftward asymmetries of TL in males, but rightward asymmetries of AW in females. Males had a greater AW than females in the right hemisphere. Moreover, the females had bilateral longer TL and a longer left BL than did males. We also found significant age-related reductions in bilateral TL and increases in bilateral AW, with males presenting more obvious age-related change than females. There were sexual differences of the CS patterns, in which Type b was the most dominant sulcal pattern in males, whereas Type a was dominant in females. Three-way ANOVA revealed sexual and asymmetry changes of TL and BL among different CS patterns. Our findings indicate that the lateralization performances of the CS manifest as sexually and regionally different. In addition, it is suggested that males may undergo a faster progress of aging compared to females. Copyright © 2015 ISDN. Published by Elsevier Ltd. All rights reserved.

Improving qPCR telomere length assays: Controlling for well position effects increases statistical power.

PubMed

Eisenberg, Dan T A; Kuzawa, Christopher W; Hayes, M Geoffrey

2015-01-01

Telomere length (TL) is commonly measured using quantitative PCR (qPCR). Although, easier than the southern blot of terminal restriction fragments (TRF) TL measurement method, one drawback of qPCR is that it introduces greater measurement error and thus reduces the statistical power of analyses. To address a potential source of measurement error, we consider the effect of well position on qPCR TL measurements. qPCR TL data from 3,638 people run on a Bio-Rad iCycler iQ are reanalyzed here. To evaluate measurement validity, correspondence with TRF, age, and between mother and offspring are examined. First, we present evidence for systematic variation in qPCR TL measurements in relation to thermocycler well position. Controlling for these well-position effects consistently improves measurement validity and yields estimated improvements in statistical power equivalent to increasing sample sizes by 16%. We additionally evaluated the linearity of the relationships between telomere and single copy gene control amplicons and between qPCR and TRF measures. We find that, unlike some previous reports, our data exhibit linear relationships. We introduce the standard error in percent, a superior method for quantifying measurement error as compared to the commonly used coefficient of variation. Using this measure, we find that excluding samples with high measurement error does not improve measurement validity in our study. Future studies using block-based thermocyclers should consider well position effects. Since additional information can be gleaned from well position corrections, rerunning analyses of previous results with well position correction could serve as an independent test of the validity of these results. © 2015 Wiley Periodicals, Inc.

Neighborhood disorder and telomeres: Connecting children’s exposure to community level stress and cellular response

PubMed Central

Theall, Katherine P.; Brett, Zoë H.; Shirtcliff, Elizabeth A.; Dunn, Erin C.; Drury, Stacy S.

2013-01-01

Our objective was to explore the utility of salivary telomere length (sTL) as an early indicator of neighborhood level social environmental risk during child development. We therefore tested the hypothesis that sTL would be associated with markers of social stress exposure in children. Children age 4–14 from 87 neighborhoods were recruited through five urban schools in New Orleans, Louisiana, U.S. Data were collected at the level of the child, family/household, and neighborhood. DNA was obtained from saliva using commercially available kits and sTL was determined for 104 children using quantitative PCR. Analysis was performed on 99 children who had complete data including sTL, social environmental stress, and additional covariates. The mean sTL value was 7.4 T/S (telomere signal/single copy signal) ratio units (± 2.4, range=2.5–18.0), and 4.7% of the variance in sTL was attributed to differences across neighborhoods. Children living in neighborhoods characterized by high disorder had an sTL value 3.2 units lower than children not living in high disordered environments (p<0.05) and their odds of having low relative sTL (defined as < 1 standard deviation below standardized z score mean) values was 3.43 times that of children not living in high disorder environments (adjusted OR=3.43, 95% CI=1.22, 9.62). Our findings are consistent with previous studies in adults demonstrating a strong link between psychosocial stress and sTL obtained from peripheral blood, consistent with previous studies in youth demonstrating an association between early life stress and sTL obtained from buccal cell DNA and offer increased support for the hypothesis that sTL represents a non-invasive biological indicator of psychosocial stress exposure (i.e., neighborhood disorder) able to reflect differences in stress exposure levels even in young children. PMID:23540366

Home Range Utilisation and Long-Range Movement of Estuarine Crocodiles during the Breeding and Nesting Season

PubMed Central

Campbell, Hamish A.; Dwyer, Ross G.; Irwin, Terri R.; Franklin, Craig E.

2013-01-01

The estuarine crocodile (Crocodylus porosus) is the apex-predator in waterways and coastlines throughout south-east Asia and Australasia. C. porosus pose a potential risk to humans, and management strategies are implemented to control their movement and distribution. Here we used GPS-based telemetry to accurately record geographical location of adult C. porosus during the breeding and nesting season. The purpose of the study was to assess how C. porosus movement and distribution may be influenced by localised social conditions. During breeding, the females (2.92±0.013 metres total length (TL), mean ± S.E., n = 4) occupied an area<1 km length of river, but to nest they travelled up to 54 km away from the breeding area. All tagged male C. porosus sustained high rates of movement (6.49±0.9 km d−1; n = 8) during the breeding and nesting period. The orientation of the daily movements differed between individuals revealing two discontinuous behavioural strategies. Five tagged male C. porosus (4.17±0.14 m TL) exhibited a ‘site-fidelic’ strategy and moved within well-defined zones around the female home range areas. In contrast, three males (3.81±0.08 m TL) exhibited ‘nomadic’ behaviour where they travelled continually throughout hundreds of kilometres of waterway. We argue that the ‘site-fidelic’ males patrolled territories around the female home ranges to maximise reproductive success, whilst the ‘nomadic’ males were subordinate animals that were forced to range over a far greater area in search of unguarded females. We conclude that C. porosus are highly mobile animals existing within a complex social system, and mate/con-specific interactions are likely to have a profound effect upon population density and distribution, and an individual's travel potential. We recommend that impacts on socio-spatial behaviour are considered prior to the implementation of management interventions. PMID:23650510

Particle discrimination of NaI(Tl) scintillator under high-energy neutron field to measure the photon energy spectrum

NASA Astrophysics Data System (ADS)

Kamada, So; Takada, Masashi; Suzuki, Toshikazu

2014-09-01

Photons are measured separately from neutrons in high-energy neutron fields using a NaI(Tl) scintillator, 7.62 cm in diameter and 7.62 cm in length, combined with a pulse-shape discrimination method. The particle discrimination capability for this scintillator is confirmed using a time-of-flight method. Neutron fields were produced by irradiating Li targets with 40 and 80 MeV proton beams at the cyclotron facility in the National Institute of Radiological Sciences. Figures of merit corresponding to particle discrimination for the scintillator at the two neutron fields are improved with higher neutron energies. Photon energy spectra for energies over 6.5 MeV can be measured using the NaI(Tl) scintillator.

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.

Dipole response of the odd-proton nucleus 205Tl up to the neutron-separation energy

DOE PAGES

Benouaret, N.; Beller, J.; Pai, H.; ...

2016-10-17

The low-lying electromagnetic dipole strength of the odd-proton nuclide 205Tl has been investigated up to the neutron separation energy exploiting the method of nuclear resonance fluorescence. In total, 61 levels of 205Tl have been identified. Lastly, the measured strength distribution of 205Tl were discussed and compared to those of even–even and even–odd mass nuclei in the same mass region as well as to calculations that have been performed within the quasi-particle phonon model.

Total Laryngectomy Versus Larynx Preservation for T4a Larynx Cancer: Patterns of Care and Survival Outcomes

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

Grover, Surbhi; Swisher-McClure, Samuel; Mitra, Nandita

2015-07-01

Purpose: To examine practice patterns and compare survival outcomes between total laryngectomy (TL) and larynx preservation chemoradiation (LP-CRT) in the setting of T4a larynx cancer, using a large national cancer registry. Methods and Materials: Using the National Cancer Database, we identified 969 patients from 2003 to 2006 with T4a squamous cell larynx cancer receiving definitive treatment with either initial TL plus adjuvant therapy or LP-CRT. Univariate and multivariable logistic regression were used to assess predictors of undergoing surgery. Survival outcomes were compared using Kaplan-Meier and propensity score–adjusted and inverse probability of treatment–weighted Cox proportional hazards methods. Sensitivity analyses were performed tomore » account for unmeasured confounders. Results: A total of 616 patients (64%) received LP-CRT, and 353 (36%) received TL. On multivariable logistic regression, patients with advanced nodal disease were less likely to receive TL (N2 vs N0, 26.6% vs 43.4%, odds ratio [OR] 0.52, 95% confidence interval [CI] 0.37-0.73; N3 vs N0, 19.1% vs 43.4%, OR 0.23, 95% CI 0.07-0.77), whereas patients treated in high case-volume facilities were more likely to receive TL (46.1% vs 31.5%, OR 1.78, 95% CI 1.27-2.48). Median survival for TL versus LP was 61 versus 39 months (P<.001). After controlling for potential confounders, LP-CRT had inferior overall survival compared with TL (hazard ratio 1.31, 95% CI 1.10-1.57), and with the inverse probability of treatment–weighted model (hazard ratio 1.25, 95% CI 1.05-1.49). This survival difference was shown to be robust on additional sensitivity analyses. Conclusions: Most patients with T4a larynx cancer receive LP-CRT, despite guidelines suggesting TL as the preferred initial approach. Patients receiving LP-CRT had more advanced nodal disease and worse overall survival. Previous studies of (non-T4a) locally advanced larynx cancer showing no difference in survival between LP-CRT and TL may not apply to T4a disease, and patients should be counseled accordingly.« less

Genetic Map Construction and Quantitative Trait Locus (QTL) Detection of Growth-Related Traits in Litopenaeus vannamei for Selective Breeding Applications

PubMed Central

Andriantahina, Farafidy; Liu, Xiaolin; Huang, Hao

2013-01-01

Growth is a priority trait from the point of view of genetic improvement. Molecular markers linked to quantitative trait loci (QTL) have been regarded as useful for marker-assisted selection (MAS) in complex traits as growth. Using an intermediate F2 cross of slow and fast growth parents, a genetic linkage map of Pacific whiteleg shrimp, Litopenaeusvannamei , based on amplified fragment length polymorphisms (AFLP) and simple sequence repeats (SSR) markers was constructed. Meanwhile, QTL analysis was performed for growth-related traits. The linkage map consisted of 451 marker loci (429 AFLPs and 22 SSRs) which formed 49 linkage groups with an average marker space of 7.6 cM; they spanned a total length of 3627.6 cM, covering 79.50% of estimated genome size. 14 QTLs were identified for growth-related traits, including three QTLs for body weight (BW), total length (TL) and partial carapace length (PCL), two QTLs for body length (BL), one QTL for first abdominal segment depth (FASD), third abdominal segment depth (TASD) and first abdominal segment width (FASW), which explained 2.62 to 61.42% of phenotypic variation. Moreover, comparison of linkage maps between L . vannamei and Penaeus japonicus was applied, providing a new insight into the genetic base of QTL affecting the growth-related traits. The new results will be useful for conducting MAS breeding schemes in L . vannamei . PMID:24086466

The nonlinear light output of NaI(Tl) detectors in the Modular Total Absorption Spectrometer

DOE PAGES

Rasco, B. C.; Fijałkowska, A.; Karny, M.; ...

2015-04-08

New detector array, the Modular Total Absorption Spectrometer (MTAS),was commissioned at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Lab(ORNL).Total absorption gamma spectra measured with MTAS are expected to improve beta-feeding patterns and beta strength functions in fission products.MTAS is constructed out of hexagonal NaI(Tl) detectors with a unique central module surrounded by 18 identical crystals assembled in three rings. The total NaI(Tl) mass of MTAS is over1000 kg.The response of the central and other 18 MTAS modules to -radiation was simulated using the GEANT4 tool kit modified to analyze the nonlinear light output of NaI(Tl).A detailedmore » description oftheGEANT4modifications madeisdiscussed.SimulatedenergyresolutionofMTAS modules is found to agree well with the measurements for single transitions of 662keV (137Cs) with 8.2% full width half maximum (FWHM),835keV (54Mn) with FWHM of 7.5% FWHM, and 1115keV (65Zn) with FWHM of 6.5%.Simulations of single and multiple -rays from 60Co are also discussed.« less

A laboratory evaluation of tagging-related mortality and tag loss in juvenile humpback chub

USGS Publications Warehouse

Ward, David L.; Persons, William R.; Young, Kirk; Stone, Dennis M.; Van Haverbeke, Randy; Knight, William R.

2015-01-01

We quantified tag retention, survival, and growth in juvenile, captive-reared Humpback Chub Gila cypha marked with three different tag types: (1) Biomark 12.5-mm, 134.2-kHz, full duplex PIT tags injected into the body cavity with a 12-gauge needle; (2) Biomark 8.4-mm, 134.2-kHz, full duplex PIT tags injected with a 16-gauge needle; and (3) Northwest Marine Technology visible implant elastomer (VIE) tags injected under the skin with a 29-gauge needle. Estimates of tag loss, tagging-induced mortality, and growth were evaluated for 60 d with each tag type for four different size-groups of fish: 40–49 mm, 50–59 mm, 60–69 mm, and 70–79 mm TL. Total length was a significant predictor of the probability of PIT tag retention and mortality for both 8-mm and 12-mm PIT tags, and the smallest fish had the highest rates of tag loss (12.5–30.0%) and mortality (7.5–20.0%). Humpback Chub of sizes 40–49 mm TL and tagged with VIE tags had no mortality but did have a 17.5% tag loss. Growth rates of all tagged fish were similar to controls. Our data indicate Humpback Chub can be effectively tagged using either 8-mm or 12-mm PIT tags with little tag loss or mortality at sizes as low as 65 mm TL.

Rediscovery of the Threatened River Sharks, Glyphis garricki and G. glyphis, in Papua New Guinea.

PubMed

White, William T; Appleyard, Sharon A; Sabub, Benthly; Kyne, Peter M; Harris, Mark; Lis, Rickson; Baje, Leontine; Usu, Thomas; Smart, Jonathan J; Corrigan, Shannon; Yang, Lei; Naylor, Gavin J P

2015-01-01

Recent surveys of the shark and ray catches of artisanal fishers in the Western Province of Papua New Guinea (PNG) resulted in the rediscovery of the threatened river sharks, Glyphis garricki and Glyphis glyphis. These represent the first records of both species in PNG since the 1960s and 1970s and highlight the lack of studies of shark biodiversity in PNG. Two individuals of G. garricki and three individuals of G. glyphis were recorded from coastal marine waters of the Daru region of PNG in October and November 2014. The two G. garricki specimens were small individuals estimated to be 100-105 cm and ~113 cm total length (TL). The three G. glyphis specimens were all mature, one a pregnant female and two adult males. These are the first adults of G. glyphis recorded to date providing a more accurate maximum size for this species, i.e. ~260 cm TL. A single pup which was released from the pregnant female G. glyphis, was estimated to be ~65 cm TL. Anecdotal information from the fishers of pregnant females of G. glyphis containing 6 or 7 pups provides the first estimate of litter size for this species. The jaws of the pregnant female G. glyphis were retained and a detailed description of the dentition is provided, since adult dentition has not been previously documented for this species. Genetic analyses confirmed the two species cluster well within samples from these species collected in northern Australia.

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).

Immune trypanolysis test with blood spotted on filter paper for epidemiological surveillance of sleeping sickness.

PubMed

Camara, Oumou; Camara, Mamadou; Lejon, Veerle; Ilboudo, Hamidou; Sakande, Hassane; Léno, Mamadou; Büscher, Philippe; Bucheton, Bruno; Jamonneau, Vincent

2014-07-01

The immune trypanolysis test (TL) is an accurate sero-diagnostic tool increasingly implemented for sleeping sickness medical surveillance, but it is restricted to the reference laboratories. To facilitate storage and transport of the test specimen, we developed a protocol for the examination of blood spotted on filter paper (TL-fp) that can be stored and shipped at ambient temperature. We compared its performance with the classical TL on plasma (TL-pl) that needs to be kept frozen until use. The study was conducted in active foci of the Republic of Guinea. In total, 438 specimens from treated and untreated sleeping sickness patients and serological suspects were tested with both methods. TL-fp gave significantly less positive results than TL-pl, but all the confirmed sleeping sickness cases were positive with the TL-fp protocol. TL-fp appears to offer a good compromise between feasibility and sensitivity to detect currently infected subjects who play a role in the transmission of Trypanosoma brucei gambiense and is useful for contributing to the elimination of gambiense sleeping sickness. © 2014 John Wiley & Sons Ltd.

Seasonal and diel habitat selection by bluegills in a shallow natural lake

USGS Publications Warehouse

Paukert, C.P.; Willis, D.W.

2002-01-01

Habitat use by bluegill Lepomis macrochirus may be dictated by the avoidance of predators and the availability of prey. Previous work suggests that bluegills large enough to avoid predators will select habitats based on foraging profitability. However, these studies focused on smaller fish (200 mm total length [TL]) bluegills in a shallow (mean depth = 1.2 m), 332-ha, natural lake (Pelican Lake, Nebraska) with both emergent and submergent vegetation distributed throughout. A total of 78 bluegills (200-273 mm TL) were implanted with radio transmitters and relocated daily for 6 d per month (April-September); up to 20 of the tagged fish were relocated every 2 h for a 24-h period once each month. Regardless of diel period, bluegills used open-water, emergent vegetation, submergent vegetation, and mixed emergent - submergent vegetation habitat types in similar proportions. During April, June, and July, male bluegills positively selected emergent vegetation, whereas female bluegills showed no vegetation selection preference during any month. Throughout the study period, bluegills never avoided open-water habitats, suggesting that larger individuals may continue to use open-water habitats in proportion to their availability. In addition, emergent vegetation appeared to be important, particularly for male bluegills. Although the mechanism for the positive selection of emergent vegetation by males was unclear, the protection or enhancement of such habitats may facilitate the preservation of quality bluegill populations in shallow lakes.

Anthropogenic spreading of anguillid herpesvirus 1 by stocking of infected farmed European eels, Anguilla anguilla (L.), in the Schlei fjord in northern Germany.

PubMed

Kullmann, B; Adamek, M; Steinhagen, D; Thiel, R

2017-11-01

The Schlei fjord in northern Germany is the recipient water of a comprehensive eel, Anguilla anguilla (L.), stocking programme. Since 2015, stocked eels become alizarin red S marked, but to date no control mechanism is implemented in this stock enhancement measure to prevent anthropogenic spreading of diseases. Consequentially, it was possible that farmed stocking cohorts of 2015 and 2016 (in total ca. 1040 kg) were subsequently tested positive for anguillid herpesvirus 1 (AngHV 1). For this study, 100 eels [total length (TL) 24.3-72.9 cm, age ca. 1-6 years] were caught in 2016 and investigated with regard to AngHV 1 infection, parasite load (Anguillicoloides crassus) and body conditions. 68% of the eels were found to be virus positive while larger specimens were more often infected. In addition, a fitted generalized linear model (area under the curve = 0.741) demonstrated that an increase in individual TL is accompanied with an increased risk of clinically relevant virus loads. Anguillicoloides crassus turned out to be an important stressor for eels, because parasite and virus load revealed a significant positive correlation. The results of this study evidently show the urgent need of a disease containment strategy for eel stocking programmes. © 2017 John Wiley & Sons Ltd.

Delayed paternal age of reproduction in humans is associated with longer telomeres across two generations of descendants

PubMed Central

Eisenberg, Dan T. A.; Hayes, M. Geoffrey; Kuzawa, Christopher W.

2012-01-01

Telomeres are repeating DNA sequences at the ends of chromosomes that protect and buffer genes from nucleotide loss as cells divide. Telomere length (TL) shortens with age in most proliferating tissues, limiting cell division and thereby contributing to senescence. However, TL increases with age in sperm, and, correspondingly, offspring of older fathers inherit longer telomeres. Using data and samples from a longitudinal study from the Philippines, we first replicate the finding that paternal age at birth is associated with longer TL in offspring (n = 2,023, P = 1.84 × 10−6). We then show that this association of paternal age with offspring TL is cumulative across multiple generations: in this sample, grandchildren of older paternal grandfathers at the birth of fathers have longer telomeres (n = 234, P = 0.038), independent of, and additive to, the association of their father’s age at birth with TL. The lengthening of telomeres predicted by each year that the father’s or grandfather’s reproduction are delayed is equal to the yearly shortening of TL seen in middle-age to elderly women in this sample, pointing to potentially important impacts on health and the pace of senescent decline in tissues and systems that are cell-replication dependent. This finding suggests a mechanism by which humans could extend late-life function as average age at reproduction is delayed within a lineage. PMID:22689985

Assessment of nonlethal methods for predicting muscle tissue mercury concentrations in coastal marine fishes.

PubMed

Piraino, Maria N; Taylor, David L

2013-11-01

Caudal fin clips and dorsolateral scales were analyzed as a potential nonlethal approach for predicting muscle tissue mercury (Hg) concentrations in marine fish. Target fish were collected from the Narragansett Bay (Rhode Island, USA) and included black sea bass Centropristis striata [n = 54, 14-55 cm total length (TL)], bluefish Pomatomus saltatrix (n = 113, 31-73 cm TL), striped bass Morone saxatilis (n = 40, 34-102 cm TL), summer flounder Paralichthys dentatus (n = 64, 18-55 cm TL), and tautog Tautoga onitis (n = 102, 27-61 cm TL). For all fish species, Hg concentrations were greatest in muscle tissue [mean muscle Hg = 0.47-1.18 mg/kg dry weight (dw)] followed by fin clips (0.03-0.09 mg/kg dw) and scales (0.01-0.07 mg/kg dw). The coefficient of determination (R (2)) derived from power regressions of intraspecies muscle Hg against fin and scale Hg ranged between 0.35 and 0.78 (mean R (2) = 0.57) and 0.14-0.37 (mean R (2) = 0.30), respectively. The inclusion of fish body size interaction effects in the regression models improved the predictive ability of fins (R (2) = 0.63-0.80; mean = 0.71) and scales (R (2) = 0.33-0.71; mean = 0.53). According to the high level of uncertainty within the regression models (R (2) values) and confidence interval widths, scale analysis was deemed an ineffective tool for estimating muscle tissue Hg concentrations in the target species. In contrast, the examination of fin clips as predictors of muscle Hg had value as a cursory screening tool; however, this method should not be the foundation for developing human consumption advisories. It is also noteworthy that the efficacy of these nonlethal techniques was highly variable across fishes and likely depends on species-specific life-history characteristics.

Similar Hydrodynamic and Morphological Changes in the Aqueous Humor Outflow Pathway after Washout and Y27632 Treatment in Monkey Eyes

PubMed Central

Lu, Zhaozeng; Zhang, Yuyan; Freddo, Thomas F.; Gong, Haiyan

2011-01-01

Our previous studies in bovine eyes demonstrated that the structural correlate to the increase in outflow facility after either Rho-kinase inhibitor Y-27632 (Y27) treatment or washout appeared to be separation between the juxtacanalicular tissue (JCT) and inner wall (IW) of the aqueous plexus, the bovine equivalent of Schlemm's canal (SC). While these findings suggest that Y27 and washout may increase outflow facility through a similar mechanism, the anatomy of bovine outflow pathway differs considerably from both the human and monkey outflow pathway; however, only the human eye does not exhibit washout. In light of this, we compared the effects of Y27 and washout on outflow facility, hydrodynamic patterns of outflow, and the morphology of the IW and JCT in monkey eyes, given that their anatomy is closer to human eyes. Twelve freshly enucleated monkey eyes were used in this study. Eyes were perfused with Dulbecco's PBS containing 5.5 mM glucose (GPBS) to establish a baseline facility at 15 mmHg. Four eyes were perfused for a short-duration (30 min) as a control, 4 eyes for a long-duration (180 min) to induce washout, and 4 eyes with GPBS+50 μM Y27 for 30 min. All eyes were then perfused with fluorescent microspheres (0.5μm; 0.002%) to label the hydrodynamic patterns of outflow and then perfusion-fixed. Confocal images of frontal sections were taken along the IW of SC. The total length (TL) and the tracer decorated length (FL) of the IW were measured to calculate the average percent effective filtration length (PEFL=FL/TL). Sections with SC were examined by light and electron microscopy. The TL of the IW and the length exhibiting separation (SL) in the JCT were measured to calculate the average percent separation length (PSL= SL/TL). Outflow facility increased 149.2% (p<0.01) from baseline after washout during long-duration perfusion, and 114.9% (p=0.004) after Y27 treatment, but did not change significantly after short-duration perfusion in control eyes (p=0.46). Distribution of the tracer labeling appeared punctate along the IW of control eyes, while a more uniform pattern was observed after washout and Y27 treatment. PEFL in washout (83.4±2.1%) and Y27 treated eyes (82.5±1.6%) was 3.4-fold larger compared to controls (24.2±4.2%, P<0.001). The JCT appeared distended with loss of connections between JCT cells and between JCT cells and their extracelluar matrix in eyes with washout or after Y-27 treatment. PSL in the JCT was 2.3-fold larger in washout eyes (77.4±3.3%) and 2.2-fold larger in Y27 treated eyes (75.2±5.3%) versus controls (33.5±5.3%, p=0.001). Significant positive correlations were found between outflow facility and PEFL, facility and PSL and between PEFL and PSL. Our data demonstrated that similar hydrodynamic and morphological changes occurred in the aqueous humor outflow pathway of monkey eyes after induction of washout and Y27 treatment. Both Y27 and washout increase outflow facility by redistributing aqueous outflow through a larger area in the JCT. These hydrodynamic changes are likely driven by morphologic changes associated with a decrease in cell-cell and cell-matrix connections in the JCT. PMID:21669200

Application of MPVR and TL-VR with 64-row MDCT in neonates with congenital EA and distal TEF.

PubMed

Wen, Yang; Peng, Yun; Zhai, Ren-You; Li, Ying-Zi

2011-03-28

To assess the application of multiple planar volume reconstruction (MPVR) and three-dimensional (3D) transparency lung volume rendering (TL-VR) with 64-row multidetector-row computed tomography (MDCT) in neonates with congenital esophageal atresia (EA) and distal tracheoesophageal fistula (TEF). Twenty neonates (17 boys, 3 girls) with EA and distal TEF at a mean age of 4.6 d (range 1-16 d) were enrolled in this study. A helical scan of 64-row MDCT was performed at the 64 mm × 0.625 mm collimation. EA and TEF were reconstructed with MPVR and TL-VR, respectively. Initial diagnosis of EA was made by chest radiography showing the inserted catheter in the proximal blind-ended esophageal pouch. Manifestations of MDCT images were compared with the findings at surgery. MDCT showed the proximal and distal esophageal pouches in 20 cases. No significant difference was observed in gaps between the proximal and distal esophageal pouches detected by MPVR and TL-VR. The lengths of gaps between the proximal and distal esophageal pouches detected by MPVR and TL-VR correlated well with the findings at surgery (R = 0.87, P < 0.001). The images of MPVR revealed the orifice of TEF in 13 cases, while TL-VR images showed the orifice of TEF in 4 cases. EA and distal TEF can be reconstructed using MPVR and TL-VR of 64-row MDCT, which is a noninvasive technique to demonstrate the distal esophageal pouches and inter-pouch distance in neonates with EA and distal TEF.

Shortened telomeres in individuals with abuse in alcohol consumption

PubMed Central

Pavanello, Sofia; Hoxha, Mirjam; Dioni, Laura; Bertazzi, Pier Alberto; Snenghi, Rossella; Nalesso, Alessandro; Ferrara, Santo Davide; Montisci, Massimo; Baccarelli, Andrea

2011-01-01

Alcohol abuse leads to earlier onset of aging-related diseases, including cancer at multiple sites. Shorter telomere length (TL) in peripheral blood leucocytes (PBLs), a marker of biological aging, has been associated with alcohol-related cancer risks. Whether alcohol abusers exhibit accelerated biological aging, as reflected in PBL-TL, has never been examined. To investigated the effect of alcohol abuse on PBL-TL and its interaction with alcohol metabolic genotypes, we examined 200 drunk-driving traffic offenders diagnosed as alcohol abusers as per the Diagnostic and Statistical Manual of Mental Disorders [DSM-IV-TR] and enrolled in a probation program, and 257 social drinkers (controls). We assessed alcohol intake using self-reported drink-units/day and conventional alcohol abuse biomarkers (serum γ-glutamyltrasferase [GGT] and mean corpuscular volume of erythrocytes [MCV]). We used multivariable models to compute TL geometric means (GM) adjusted for age, smoking, BMI, diet, job at elevated risk of accident, genotoxic exposures. TL was nearly halved in alcohol abusers compared to controls (GMs 0.42 vs. 0.87 relative T/S ratio; P<0.0001) and decreased in relation with increasing drink-units/day (P-trend=0.003). Individuals drinking >4 drink-units/day had substantially shorter TL than those drinking 4 drink-units/day (GMs 0.48 vs. 0.61 T/S, P=0.002). Carriers of the common ADH1B*1/*1 (rs1229984) genotype were more likely to be abusers (P=0.008), reported higher drink-units/day (P=0.0003), and exhibited shorter TL (P<0.0001). The rs698 ADH1C and rs671 ALDH2 polymorphisms were not associated with TL. The decrease in PBL-TL modulated by the alcohol metabolic genotype ADH1B*1/*1 may represent a novel mechanism potentially related to alcohol carcinogenesis in alcohol abusers. PMID:21351086

Shortened telomeres in individuals with abuse in alcohol consumption.

PubMed

Pavanello, Sofia; Hoxha, Mirjam; Dioni, Laura; Bertazzi, Pier Alberto; Snenghi, Rossella; Nalesso, Alessandro; Ferrara, Santo Davide; Montisci, Massimo; Baccarelli, Andrea

2011-08-15

Alcohol abuse leads to earlier onset of aging-related diseases, including cancer at multiple sites. Shorter telomere length (TL) in peripheral blood leucocytes (PBLs), a marker of biological aging, has been associated with alcohol-related cancer risks. Whether alcohol abusers exhibit accelerated biological aging, as reflected in PBL-TL, has never been examined. To investigated the effect of alcohol abuse on PBL-TL and its interaction with alcohol metabolic genotypes, we examined 200 drunk-driving traffic offenders diagnosed as alcohol abusers as per the Diagnostic and Statistical Manual of Mental Disorders [DSM-IV-TR] and enrolled in a probation program, and 257 social drinkers (controls). We assessed alcohol intake using self-reported drink-units/day and conventional alcohol abuse biomarkers (serum γ-glutamyltrasferase [GGT] and mean corpuscular volume of erythrocytes [MCV]). We used multivariable models to compute TL geometric means (GM) adjusted for age, smoking, BMI, diet, job at elevated risk of accident, genotoxic exposures. TL was nearly halved in alcohol abusers compared with controls (GMs 0.42 vs. 0.87 relative T/S ratio; p<0.0001) and decreased in relation with increasing drink-units/day (p-trend=0.003). Individuals drinking >4 drink-units/day had substantially shorter TL than those drinking ≤4 drink-units/day (GMs 0.48 vs. 0.61 T/S, p=0.002). Carriers of the common ADH1B*1/*1 (rs1229984) genotype were more likely to be abusers (p=0.008), reported higher drink-units/day (p=0.0003), and exhibited shorter TL (p<0.0001). The rs698 ADH1C and rs671 ALDH2 polymorphisms were not associated with TL. The decrease in PBL-TL modulated by the alcohol metabolic genotype ADH1B*1/*1 may represent a novel mechanism potentially related to alcohol carcinogenesis in alcohol abusers. Copyright © 2011 UICC.

The power of exercise: buffering the effect of chronic stress on telomere length.

PubMed

Puterman, Eli; Lin, Jue; Blackburn, Elizabeth; O'Donovan, Aoife; Adler, Nancy; Epel, Elissa

2010-05-26

Chronic psychological stress is associated with detrimental effects on physical health, and may operate in part through accelerated cell aging, as indexed by shorter telomeres at the ends of chromosomes. However, not all people under stress have distinctly short telomeres, and we examined whether exercise can serve a stress-buffering function. We predicted that chronic stress would be related to short telomere length (TL) in sedentary individuals, whereas in those who exercise, stress would not have measurable effects on telomere shortening. 63 healthy post-menopausal women underwent a fasting morning blood draw for whole blood TL analysis by a quantitative polymerase chain reaction method. Participants completed the Perceived Stress Scale (Cohen et al., 1983), and for three successive days reported daily minutes of vigorous activity. Participants were categorized into two groups-sedentary and active (those getting Centers for Disease Control-recommended daily amount of activity). The likelihood of having short versus long telomeres was calculated as a function of stress and exercise group, covarying age, BMI and education. Logistic regression analyses revealed a significant moderating effect of exercise. As predicted, among non-exercisers a one unit increase in the Perceived Stress Scale was related to a 15-fold increase in the odds of having short telomeres (p<.05), whereas in exercisers, perceived stress appears to be unrelated to TL (B = -.59, SE = .78, p = .45). Vigorous physical activity appears to protect those experiencing high stress by buffering its relationship with TL. We propose pathways through which physical activity acts to buffer stress effects.

Child mortality, hypothalamic-pituitary-adrenal axis activity and cellular aging in mothers.

PubMed

Barha, Cindy K; Salvante, Katrina G; Hanna, Courtney W; Wilson, Samantha L; Robinson, Wendy P; Altman, Rachel M; Nepomnaschy, Pablo A

2017-01-01

Psychological challenges, including traumatic events, have been hypothesized to increase the age-related pace of biological aging. Here we test the hypothesis that psychological challenges can affect the pace of telomere attrition, a marker of cellular aging, using data from an ongoing longitudinal-cohort study of Kaqchikel Mayan women living in a population with a high frequency of child mortality, a traumatic life event. Specifically, we evaluate the associations between child mortality, maternal telomere length and the mothers' hypothalamic-pituitary-adrenal axis (HPAA), or stress axis, activity. Child mortality data were collected in 2000 and 2013. HPAA activity was assessed by quantifying cortisol levels in first morning urinary specimens collected every other day for seven weeks in 2013. Telomere length (TL) was quantified using qPCR in 55 women from buccal specimens collected in 2013. Shorter TL with increasing age was only observed in women who experienced child mortality (p = 0.015). Women with higher average basal cortisol (p = 0.007) and greater within-individual variation (standard deviation) in basal cortisol (p = 0.053) presented shorter TL. Non-parametric bootstrapping to estimate mediation effects suggests that HPAA activity mediates the effect of child mortality on TL. Our results are, thus, consistent with the hypothesis that traumatic events can influence cellular aging and that HPAA activity may play a mediatory role. Future large-scale longitudinal studies are necessary to confirm our results and further explore the role of the HPAA in cellular aging, as well as to advance our understanding of the underlying mechanisms involved.

Child mortality, hypothalamic-pituitary-adrenal axis activity and cellular aging in mothers

PubMed Central

Barha, Cindy K.; Salvante, Katrina G.; Hanna, Courtney W.; Wilson, Samantha L.; Robinson, Wendy P.; Altman, Rachel M.

2017-01-01

Psychological challenges, including traumatic events, have been hypothesized to increase the age-related pace of biological aging. Here we test the hypothesis that psychological challenges can affect the pace of telomere attrition, a marker of cellular aging, using data from an ongoing longitudinal-cohort study of Kaqchikel Mayan women living in a population with a high frequency of child mortality, a traumatic life event. Specifically, we evaluate the associations between child mortality, maternal telomere length and the mothers’ hypothalamic-pituitary-adrenal axis (HPAA), or stress axis, activity. Child mortality data were collected in 2000 and 2013. HPAA activity was assessed by quantifying cortisol levels in first morning urinary specimens collected every other day for seven weeks in 2013. Telomere length (TL) was quantified using qPCR in 55 women from buccal specimens collected in 2013. Results: Shorter TL with increasing age was only observed in women who experienced child mortality (p = 0.015). Women with higher average basal cortisol (p = 0.007) and greater within-individual variation (standard deviation) in basal cortisol (p = 0.053) presented shorter TL. Non-parametric bootstrapping to estimate mediation effects suggests that HPAA activity mediates the effect of child mortality on TL. Our results are, thus, consistent with the hypothesis that traumatic events can influence cellular aging and that HPAA activity may play a mediatory role. Future large-scale longitudinal studies are necessary to confirm our results and further explore the role of the HPAA in cellular aging, as well as to advance our understanding of the underlying mechanisms involved. PMID:28542264

Age and Growth of Endangered Smalltooth Sawfish (Pristis pectinata) Verified with LA-ICP-MS Analysis of Vertebrae

PubMed Central

Scharer, Rachel M.; Patterson III, William F.; Carlson, John K.; Poulakis, Gregg R.

2012-01-01

Endangered smalltooth sawfish (Pristis pectinata) were opportunistically sampled in south Florida and aged by counting opaque bands in sectioned vertebrae (n = 15). Small sample size precluded traditional age verification, but fish collected in spring and summer had translucent vertebrae margins, while fish collected in winter had opaque margins. Trends in Sr:Ca measured across vertebrae with laser ablation-inductively coupled plasma-mass spectrometry corresponded well to annual salinity trends observed in sawfish estuarine nursery habitats in south Florida, thus serve as a chemical marker verifying annual formation of opaque bands. Based on that finding and assumptions about mean birth date and timing of opaque band formation, estimated age ranged from 0.4 y for a 0.60 m total length (TL) male to 14.0 y for a 4.35 m TL female. Von Bertalanffy growth parameters computed from size at age data were 4.48 m for L∞, 0.219 y−1for k, and −0.81 y for t0. Results of this study have important implications for sawfish conservation as well as for inferring habitat residency of euryhaline elasmobranchs via chemical analysis of vertebrae. PMID:23082225

[Reproduction of Joturus pichardi and Agonostomus monticola (Mugiliformes: Mugilidae) in rivers of the Sierra Nevada de Santa Marta, Colombia].

PubMed

Eslava Eljaiek, Pedro; Díaz Vesga, Roy

2011-12-01

The freshwater mugilids Joturus pichardi and Agonostomus monticola, have been documented on ecological and distribution aspects, mainly for Central American populations, nevertheless, little information is available on their reproductive aspects, specifically in Colombian freshwater environments. Reproductive biology of the mugilids J. pichardi and A. monticola from Sierra Nevada de Santa Marta (SNSM) rivers was studied between July 2005 and December 2006. A total of 14 specimens of J. pichardi and 320 of A. monticola were collected. The reproductive biology was analyzed by means of: sexual proportion, gonadosomatic index, and mean size at maturity, fecundity and oocyte diameter. Additionally, a bioassay was carried out to evaluate the effect of salinity on spermatic motility and its possible relationship with the species' spawning area. These mugilids share habitats with similar ecological characteristics, in which strong currents; clear water and stony areas stand out. Gonadal maturity indicators and indirect evidence are presented to support the relationship between reproductive maturity and higher rainfall levels in the area (September, October and November), as well as the catadromous migration of J. pichardi and A. monticola. This last species females outnumbered males with a sex ratio of 2.3:1. Females mean size at maturity was 172mm of their total length (TL) and 108mm TL for males. Fecundity (F) was 23 925 +/- 4 581 eggs per gram of gonad, and was related to size by the equation F = 395.1TL(1.281); besides, the mean oocyte diameter was 362 +/- 40 microm. Considering the salinity effect on sperm motility in both species, results suggested that J. pichardi spawned in estuarine environments but the species did not migrate to fully marine environments; however, A. monticola withstood a broad range of salinity, suggesting a spawning from intermediate to total saline environments. Both species have high culturing potentials, considering that their feeding is based on plant and macroinvertebrates, their meat quality and the size they are able to reach. These species represent an interesting resource to the fisher groups of the region and should be integrally assessed.

50 CFR 622.436 - Size limits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... intact. (a) Yellowtail snapper. The minimum size limit for yellowtail snapper is 12 inches (30.5 cm), TL... inches (20.3 cm), fork length. [78 FR 22952, Apr. 17, 2013, as amended at 78 FR 45896, July 30, 2013] ...

50 CFR 622.436 - Size limits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... intact. (a) Yellowtail snapper. The minimum size limit for yellowtail snapper is 12 inches (30.5 cm), TL... inches (20.3 cm), fork length. [78 FR 22952, Apr. 17, 2013, as amended at 78 FR 45896, July 30, 2013] ...

The Last Frontier: Catch Records of White Sharks (Carcharodon carcharias) in the Northwest Pacific Ocean

PubMed Central

Christiansen, Heather M.; Lin, Victor; Tanaka, Sho; Velikanov, Anatoly; Mollet, Henry F.; Wintner, Sabine P.; Fordham, Sonja V.; Fisk, Aaron T.; Hussey, Nigel E.

2014-01-01

White sharks are highly migratory apex predators, globally distributed in temperate, sub-tropical, and tropical waters. Knowledge of white shark biology and ecology has increased recently based on research at known aggregation sites in the Indian, Atlantic, and Northeast Pacific Oceans; however, few data are available for the Northwest Pacific Ocean. This study provides a meta-analysis of 240 observations of white sharks from the Northwest Pacific Ocean between 1951 and 2012. Records comprise reports of bycatch in commercial fisheries, media accounts, personal communications, and documentation of shark-human interactions from Russia (n = 8), Republic of Korea (22), Japan (129), China (32), Taiwan (45), Philippines (1) and Vietnam (3). Observations occurred in all months, excluding October-January in the north (Russia and Republic of Korea) and July-August in the south (China, Taiwan, Philippines, and Vietnam). Population trend analysis indicated that the relative abundance of white sharks in the region has remained relatively stable, but parameterization of a 75% increase in observer effort found evidence of a minor decline since 2002. Reliably measured sharks ranged from 126–602 cm total length (TL) and 16–2530 kg total weight. The largest shark in this study (602 cm TL) represents the largest measured shark on record worldwide. For all countries combined the sex ratio was non-significantly biased towards females (1∶1.1; n = 113). Of 60 females examined, 11 were confirmed pregnant ranging from the beginning stages of pregnancy (egg cases) to near term (140 cm TL embryos). On average, 6.0±2.2 embryos were found per litter (maximum of 10) and gestation period was estimated to be 20 months. These observations confirm that white sharks are present in the Northwest Pacific Ocean year-round. While acknowledging the difficulties of studying little known populations of a naturally low abundance species, these results highlight the need for dedicated research to inform regional conservation and management planning. PMID:24740299

The last frontier: catch records of white sharks (Carcharodon carcharias) in the Northwest Pacific Ocean.

PubMed

Christiansen, Heather M; Lin, Victor; Tanaka, Sho; Velikanov, Anatoly; Mollet, Henry F; Wintner, Sabine P; Fordham, Sonja V; Fisk, Aaron T; Hussey, Nigel E

2014-01-01

White sharks are highly migratory apex predators, globally distributed in temperate, sub-tropical, and tropical waters. Knowledge of white shark biology and ecology has increased recently based on research at known aggregation sites in the Indian, Atlantic, and Northeast Pacific Oceans; however, few data are available for the Northwest Pacific Ocean. This study provides a meta-analysis of 240 observations of white sharks from the Northwest Pacific Ocean between 1951 and 2012. Records comprise reports of bycatch in commercial fisheries, media accounts, personal communications, and documentation of shark-human interactions from Russia (n = 8), Republic of Korea (22), Japan (129), China (32), Taiwan (45), Philippines (1) and Vietnam (3). Observations occurred in all months, excluding October-January in the north (Russia and Republic of Korea) and July-August in the south (China, Taiwan, Philippines, and Vietnam). Population trend analysis indicated that the relative abundance of white sharks in the region has remained relatively stable, but parameterization of a 75% increase in observer effort found evidence of a minor decline since 2002. Reliably measured sharks ranged from 126-602 cm total length (TL) and 16-2530 kg total weight. The largest shark in this study (602 cm TL) represents the largest measured shark on record worldwide. For all countries combined the sex ratio was non-significantly biased towards females (1∶1.1; n = 113). Of 60 females examined, 11 were confirmed pregnant ranging from the beginning stages of pregnancy (egg cases) to near term (140 cm TL embryos). On average, 6.0±2.2 embryos were found per litter (maximum of 10) and gestation period was estimated to be 20 months. These observations confirm that white sharks are present in the Northwest Pacific Ocean year-round. While acknowledging the difficulties of studying little known populations of a naturally low abundance species, these results highlight the need for dedicated research to inform regional conservation and management planning.

Early life history stages of Gulf sturgeon in the Suwannee River, Florida

USGS Publications Warehouse

Sulak, K.J.; Clugston, James P.

1998-01-01

Egg sampling confirmed that Suwannee River Gulf sturgeon Acipenser oxyrinchus desotoi, a subspecies of Atlantic sturgeon A. o. oxyrinchus use the same spawning site at river kilometer (rkm) 215 from the month of the river each year. Forty-nine eggs were recorded in 1995, and 368 were recorded in 1996. Spawning began 4-7 d after the March new moon in both years and lasted 10-11 d; in 1996, a second 10-d spawning round began on the April new moon. Developmental synchrony among eggs recovered suggested several discrete spawning events in both years. Total eggs deposited for three 1996 sampling days was estimated as 405,600-711,000/d, approximating the fecundity range of a large female Gulf sturgeon. Eggs were found only in the southern half of the river, an area with surface currents of 0.5-1.5 m/s and numerous eddies producing reverse bottom currents of 0.1-0.5 m/s. Egg substrate consisted of bedrock limestone thinly overlain by fine sand and densely distributed elliptical gravel 2-10 cm in diameter. Eggs were found predominantly in depths of 2-4 m at water temperatures of 17-21??C, conductivities of 50-100 ??S, and dissolved oxygen levels exceeding 5.0 mg/L. The Cody Scarp, 15 rkm above the spawning ground, may mark the upstream limit of spawning areas in the river. Three 2-4-month-old riverine juveniles (82-115 mm total length, TL) collected are the smallest yet captured from any river. Data for 18 riverine age-0 juveniles (to 350 mm TL) suggest that this stage lasts 6-10 months, terminating with migration of fish to the river mouth in January-February. Less than 2% of 461 juveniles captured at the estuarine river mouth (1990-1993) were under 350 mm TL. Riverine age-0 fish were collected over long shallow stretches (typically <4 m deep) of relatively barren sand (rkm 12-238).

Walleye population and fishery responses after elimination of legal harvest on Escanaba Lake, Wisconsin

USGS Publications Warehouse

Haglund, Justin M.; Isermann, Daniel A.; Sass, Greg G.

2016-01-01

Implementing harvest regulations to eliminate or substantially reduce (≥90%) the exploitation of Walleyes Sander vitreus in recreational fisheries may increase population size structure, but these measures also could reduce angler effort because many Walleye anglers are harvest oriented. We analyzed data collected during 1995–2015 to determine whether Walleye population and fishery metrics in Escanaba Lake, Wisconsin, changed after a minimum TL limit of 71 cm with a one-fish daily bag limit was implemented in 2003. This change eliminated the legal harvest of Walleyes after several decades during which annual exploitation averaged 34%. We detected a significant increase in the loge density of adult females after the regulation change, but the loge density of all adults and adult males did not differ between periods. Mean TL of adult males was significantly greater after the regulation change, but the mean TL of females and the proportional size distribution of preferred-length fish (≥51 cm TL) were similar between periods. Sex-specific mean TLs at age 5 did not differ between periods. Loge density of age-0 Walleyes did not change after 2003, but variation in age-0 density was lower. Total angler effort and the effort for anglers targeting Walleyes were significantly lower (35% and 60% declines, respectively) after the regulation change, whereas catch rates for both angler categories did not differ between periods. Our results suggest that implementing highly restrictive regulations that greatly reduce or eliminate legal harvest will not always increase angler catch rates and population size structure. Highly restrictive regulations may also deter anglers from using a fishery when many other fisheries are available. Our findings are useful for fishery managers who may work with anglers holding the belief that lower exploitation is a potential remedy for low Walleye size structure, even when density and growth suggest that there is limited potential for improvement.

Accelerated leukocyte telomere erosion in schizophrenia: Evidence from the present study and a meta-analysis.

PubMed

Rao, Shuquan; Kota, Lakshmi Narayanan; Li, Zongchang; Yao, Yao; Tang, Jinsong; Mao, Canquan; Jain, Sanjeev; Xu, Yong; Xu, Qi

2016-08-01

Human telomeres consist of tandem nucleotide repeats (TTAGGG) and associated proteins, and telomere length (TL) is reduced progressively with cell division over the lifespan. Telomere erosion might be accelerated or prevented to varying degrees when exposure to serious medical illnesses. In previous studies, an association between TL decrease and schizophrenia has been extensively reported; however, the results remain largely controversial. To further investigate TL in schizophrenia patients and reconcile this controversy, we first measured leucocyte TL (LTL) in our samples (52 paranoid schizophrenia, 89 non-paranoid patients and 120 controls), and then conducted a comprehensive meta-analysis of the existing results of LTL in patients of schizophrenia compared to healthy subjects. Totally, 11 studies encompassing 1243 patients of schizophrenia and 1274 controls were included in the final meta-analysis model. In our samples, significant reduction of LTL in paranoid schizophrenia was observed compared to controls (F = 50.88, P < 0.001); whereas there was no significant difference in LTL between non-paranoid schizophrenia and controls (F = 0.842, P = 0.360). For meta-analysis, random-effects model showed significant LTL decrease in patients of schizophrenia when compared to controls (Z = 2.07, P = 0.039, SMD = -0.48, 95% CI = -0.94 to -0.03). Moreover, a marginal decrease in LTL was observed in medicated patients (Z = 1.92, P = 0.055, SMD = -0.58, 95% CI = -1.18-0.01) and those patients with poor response to antipsychotics (Z = 1.76, P = 0.078, SMD = -0.60, 95% CI = -1.27-0.07). In conclusion, we observed significant reduction of LTL in individuals with schizophrenia compared with controls. However, all the studies included in the meta-analysis were cross-sectional, and better controlled long-term studies are needed to replicate this result. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of acyl chain length on selective biocatalytic deacylation on O-aryl glycosides and separation of anomers.

PubMed

Aggarwal, Neha; Arya, Anu; Mathur, Divya; Singh, Sukhdev; Tyagi, Abhilash; Kumar, Rajesh; Rana, Neha; Singh, Rajendra; Prasad, Ashok K

2014-04-01

It has been demonstrated that Lipozyme® TL IM (Thermomyces lanuginosus lipase immobilised on silica) can selectively deacylate the ester function involving the C-5' hydroxyl group of α-anomers over the other acyl functions of anomeric mixture of peracylated O-aryl α,β-D-ribofuranoside. The analysis of results of biocatalytic deacylation reaction revealed that the reaction time decreases with the increase in the acyl chain length from C1 to C4. The unique selectivity of Lipozyme® TL IM has been harnessed for the separation of anomeric mixture of peracylated O-aryl α,β-D-ribofuranosides, The lipase mediated selective deacylation methodology has been used for the synthesis of O-aryl α-D-ribofuranosides and O-aryl β-D-ribofuranosides in pure forms, which can be used as chromogenic substrate for the detection of pathogenic microbial parasites containing glycosidases. Copyright © 2014. Published by Elsevier Inc.

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.

Individual stem value recovery of modified and conventional tree-length systems in the southeastern United States

Treesearch

Amanda H. Lang; Shawn A. Baker; W. Dale Greene; Glen E. Murphy

2010-01-01

We compared value recovery of a modified treelength (MTL) logging system that measures product diameter and length using a Waratah 626 harvester head to that of a treelength (TL) system that estimates dimensions. A field test compared the actual value cut to the maximum potential value suggested by the log bucking optimization program Assessment of Value by Individual...

Low-Power Testing of Losses in Millimeter-Wave Transmission Lines for High-Power Applications

PubMed Central

Han, S. T.; Comfoltey, E. N.; Shapiro, M. A.; Sirigiri, J. R.; Tax, D. S.; Temkin, R. J.; Woskov, P. P.; Rasmussen, D. A.

2008-01-01

We report the measurement of small losses in transmission line (TL) components intended for high-power millimeter-wave applications. Measurements were made using two different low-power techniques: a coherent technique using a vector network analyzer (VNA) and an incoherent technique using a radiometer. The measured loss in a 140 GHz 12.7 mm diameter TL system, consisting of 1.7 m of circular corrugated waveguide and three miter bends, is dominated by the miter bend loss. The measured loss was 0.3±0.1 dB per miter bend using a VNA; and 0.22±0.1 dB per miter bend using a radiometer. Good agreement between the two measurement techniques implies that both are useful for measuring small losses. To verify the methodology, the VNA technique was employed to measure the extremely small transmission loss in a 170 GHz ITER prototype TL system consisting of three lengths of 1 m, 63.5 mm diameter, circular corrugated waveguide and two miter bends. The measured loss of 0.05±0.02 dB per miter bend may be compared with the theoretical loss of 0.027 dB per miter bend. These results suggest that low-power testing of TL losses, utilizing a small, simple TL system and a VNA, is a reliable method for evaluating performance of low-loss millimeter-wave TL components intended for use in high-power applications. PMID:19081774

Hooking mortality and physiological responses of striped bass angled in freshwater and held in live-release tubes

USGS Publications Warehouse

Bettinger, J.M.; Tomasso, J.R.; Isely, J.J.

2005-01-01

Mortality and physiological responses of adult striped bass Morone saxatilis angled from Lake Murray, South Carolina, and held in live-release tubes were evaluated during the spring and summer of 2003. To estimate mortality, we attached external ultrasonic transmitters to 59 striped bass (mean total length [TL] = 585 mm). Striped bass were caught with angling gear, tagged, and immediately released or held in live-release tubes for 2, 4, or 6 h prior to release. No mortality of striped bass was observed during spring. Overall mortality during summer was 83%. Mortality of summer-caught striped bass was not related to tube residence time, fish TL, depth of capture, or surface water temperature. To characterize physiological stress, we measured the plasma cortisol, glucose, lactate, and osmolality levels of 62 additional striped bass (mean TL = 563 mm) that were angled and immediately released or angled and held in live-release tubes. Plasma cortisol, glucose, lactate, and osmolality were positively related to tube residence time. When the hematological characteristics were considered only in relation to tube residence time, responses indicative of physiological stress continued for about 150 min, after which blood chemistry began to return to normal. Live-release tubes appear to be useful for keeping striped bass alive when they are angled from cool water, but they are not effective for striped bass angled from warm water. The high summer mortality of striped bass suggests a need for restrictive fishing regulations during the summer for the Lake Murray striped bass fishery. ?? Copyright by the American Fisheries Society 2005.

Study of the dairy characters of lactating Murrah buffaloes on the basis of body parts measurements.

PubMed

Dhillod, Sandeep; Kar, Dipankar; Patil, C S; Sahu, Subhasish; Singh, Narender

2017-01-01

The aim of the study was to correlate the milk yield of Murrah buffaloes with certain body parts measurements. A total of 70 lactating Murrah buffaloes were selected from Buffalo Farm, Lala Lajpat Rai University of Veterinary and Animal Science, Hisar and were randomly selected in a range from first to fifth parity. Traits studied were 305 days milk yield (MY), body weight (BW), body length (BL), muzzle width (MW), height at wither (HW), abdominal girth (AG), chest girth (CG), body depth fore, body depth rear, hip bone distance (HBD), pin bone distance (PBD), skin thickness (STK), and tail length (TL). Data were collected and statically analyzed by Pearson's correlation method. The result of this study showed that Murrah buffaloes had the average 2604.8±39.5 kg for MY, 556.1±4.9 kg for BW, and 152.2±0.8 cm for BL. This study showed that buffaloes had positive significant (p<0.05) correlation between MY and BW (0.26). Highly significant (p<0.01) correlation was observed between MY and AG (0.64), MW (0.42). Significant (p<0.01) negative correlation was observed between MY and STK (-0.79). Different body part measurements (BW, BL, HW, AG, CG, MW, TL, BD, PBD, HBD, STK) were significantly correlated with each other. This study can be helpful as a selection tool to enhance and evaluate the production potential by setting standards of Murrah buffalo breed. BW, abdominal growth, muzzle thickness, and STK were found key factors while selecting a dairy Murrah buffalo.

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.

0-6711 : short radius MASH TL-3 guardrail treatment.

DOT National Transportation Integrated Search

2014-11-01

When a roadway intersects a highway with : restrictive features, such as a bridge rail, it becomes : difficult to fit a guardrail with the proper length, : transitions, and end treatment along the highway. : Possible solutions include relocating the ...

Magnetism and superconductivity of some Tl-Cu oxides

NASA Technical Reports Server (NTRS)

Datta, Timir

1990-01-01

Many copper oxide based Thallium compounds have now been discovered. In comparison to the Bi-compounds, the Tl-system shows a richer diversity; viz., High Temperature Superconductors (HTSC) can be obtained with either one or two Tl-0 layers (m = 1,2); also, the triple-digit phases are easier to synthesize. The value of d, oxygen stoichiometry, is critical to achieving superconductivity. The Tl system is robust to oxygen loss; Tl may be lost or incorporated by diffusion. A diffusion coefficient equal to 10 ms at 900 C was determined. Both ortho-rhombic and tetragonal structures are evidenced, but HTSC behavior is indifferent to the crystal symmetry. This system has the highest T(sub c) confirmed. T(sub c) generally increases with p, the number of CuO layers, but tends to saturate at p = 3. Zero resistance as high as 125K has been observed. Most of these HTSC's are hole type, but the Ce-doped specimens may be electronic. The magnetic aspects were studied; because in addition to defining the perfectly diamagnetic ground state as in the conventional superconductors, magnetism of the copper oxides show a surprising variety. This is true of both the normal and the superconducting states. Also, due to the large phonon contribution to the specific heat at the high T(sub c) accurate thermal measurement of important parameters such as the sp. heat jump, electronic density of states, D(Ef) and coherence length are uncertain, and thus, are estimated from the magnetic results. Results from the Tl-system CuO, LaBaCuO, 120 and the Bi-CuO compounds are discussed. The emphasis is on the role of magnetism in the TlCuO HTSC, but technological aspects are also pointed out.

Magnetism and superconductivity of some Tl-Cu oxides

NASA Technical Reports Server (NTRS)

Datta, Timir

1991-01-01

Many copper oxide based Thallium compounds are now known. In comparison to the Bi-compounds, the Tl-system shows a richer diversity; i.e., High Temperature Superconductors (HTSC) can be obtained with either one or two Tl-0 layers (m = 1,2); also, the triple-digit phases are easier to synthesize. The value of d, oxygen stoichiometry, is critical to achieving superconductivity. The Tl system is robust to oxygen loss; Tl may be lost or incorporated by diffusion. A diffusion coefficient equal to 10 ms at 900 C was determined. Both ortho-rhombic and tetragonal structures are found, but HTSC behavior is indifferent to the crystal symmetry. This system has the highest T(sub c) confirmed. T(sub c) generally increases with p, the number of CuO layers, but tends to saturate at p = 3. Zero resistance was observed at temperatures as great as 125 K. Most of these HTSC's are hole type, but the Ce-doped specimens may be electronic. The magnetic aspects were studied; because in addition to defining the perfectly diamagnetic ground state as in conventional superconductors, magnetism of the copper oxides show a surprising variety. This is true of both the normal and the superconducting states. Also, due to the large phonon contribution to the specific heat at the high T(sub c) jump, electronic density of states, D(Ef), and coherence length are uncertain, and thus, are estimated from the magnetic results. Results from the Tl-system CuO, LaBaCuO,120 and the Bi-CuO compounds are discussed. The emphasis is on the role of magnetism in the Tl-CuO HTSC, but technological aspects are also pointed out.

Fish trophic level and the similarity of non-specific larval parasite assemblages.

PubMed

Timi, J T; Rossin, M A; Alarcos, A J; Braicovich, P E; Cantatore, D M P; Lanfranchi, A L

2011-03-01

Whereas the effect of parasites on food webs is increasingly recognised and has been extensively measured and modelled, the effect of food webs on the structure of parasite assemblages has not been quantified in a similar way. Here, we apply the concept of decay in community similarity with increasing distance, previously used for parasites in geographical, phylogenetic and ontogenetic contexts, to differences in the trophic level (TL) based on diet composition of fishes. It is proposed as an accurate quantitative method to measure rates of assemblage change as a function of host feeding habits and is applied, to our knowledge for the first time, across host species in marine waters. We focused on a suite of 15 species of trophically-transmitted and non-specific larval helminths across 16 fish species (1783 specimens, six orders, 14 families) with different sizes and TLs, gathered from the same ecosystem. Not all host species harboured the same number and types of parasites, reflecting the differences in their ecological characteristics. Using differences in TL and body length as measurements of size and trophic distances, we found that similarity at both infracommunity and component community levels showed a very clear decay pattern, based on parasite abundance and relative abundance, with increasing distance in TL, but was not related to changes in fish size, with TL thus emerging as the main explanatory factor for similarity of parasite assemblages. Furthermore, the relationships between host TL and assemblage similarity allowed identification of fishes for which the TL was under- or over-estimated and prediction of the TL of host species based on parasite data alone. Copyright © 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Age and growth of round gobies in Lake Huron: Implications for food web dynamics

USGS Publications Warehouse

Duan, You J.; Madenjian, Charles P.; Xie, Cong X.; Diana, James S.; O'Brien, Timothy P.; Zhao, Ying M.; He, Ji X.; Farha, Steve A.; Huo, Bin

2016-01-01

Although the round goby (Neogobius melanostomus) has become established throughout the Laurentian Great Lakes, information is scarce on spatial variation in round goby growth between and within lakes. Based on a sample of 754 specimens captured in 2014, age, growth, and mortality of round gobies at four locations in Lake Huron were assessed via otolith analysis. Total length (TL) of round gobies ranged from 44 to 111 mm for Saginaw Bay, from 45 to 115 mm for Rockport, from 50 to 123 mm for Hammond Bay, and from 51 to 118 mm for Thunder Bay. Estimated ages of round gobies ranged from 2 to 5 years for Saginaw Bay, from 2 to 6 years for Rockport, and from 2 to 7 years for Hammond Bay and Thunder Bay. Sex-specific, body–otolith relationships were used to back-calculate total lengths at age, which were then fitted to von Bertalanffy growth models. For each sex, round goby growth showed significant spatial variation among the four locations within Lake Huron. At all four locations in Lake Huron, males grew significantly faster than females and attained a larger asymptotic length than females. Annual mortality rate estimates were high (62 to 85%), based on catch-curve analysis, suggesting that round gobies may be under predatory control in Lake Huron.

Comparison of timber utilization between a tree-length and an in-wood chipping harvesting operations

Treesearch

Suraj Prasad Shrestha; Bobby L. Lanford

2002-01-01

Two 25-year old pine plantations in Alabama, one for in-wood-chipping (IWC) and another for tree length (TL) harvesting operations, were selected to determine the proportion of the standing merchantable timber resource and value that got to a manufacturing facility. Amount of sawtimber after merchandizing in the woods was found to be 80.6 percent of inside bark volume...

Early exclusive breastfeeding is associated with longer telomeres in Latino preschool children.

PubMed

Wojcicki, Janet M; Heyman, Melvin B; Elwan, Deena; Lin, Jue; Blackburn, Elizabeth; Epel, Elissa

2016-08-01

Telomere length (TL) is a marker of cellular aging, with the majority of lifetime attrition occurring during the first 4 y. Little is known about risk factors for telomere shortening in childhood. We evaluated the relation between early life feeding variables and preschool TL. We assessed the relation between dietary, feeding, and weight-associated risk factors measured from birth and TL from blood samples taken at 4 y of age (n = 108) and 5 y of age (n = 92) in a cohort of urban, Latino children (n = 121 individual children). Feeding variables were evaluated in children with repeat measurements (n = 77). Mean TL (in bp) was associated with exclusive breastfeeding at 4-6 wk of age (adjusted coefficient: 353.85; 95% CI: 72.81, 634.89; P = 0.01), maternal TL (adjusted coefficient: 0.32; 95% CI: 0.11, 0.54; P < 0.01), and older paternal age (adjusted coefficient: 33.27; 95% CI: 4.10, 62.44; P = 0.03). The introduction of other foods or drinks in addition to breast-milk or replacement-milk substitutes before 4-6 wk of age was associated with mean TL at 4 and 5 y of age (adjusted coefficient: -457.01; 95% CI: -720.50, -193.51; P < 0.01). Infant obesity at 6 mo of age and soda consumption at 4 y of age mediated the relation in part between exclusive breastfeeding at 4-6 wk of age and mean TL at 4 and 5 y of age. High soda consumption at 3 y of age was associated with an accelerated attrition from 4 to 5 y of age (adjusted coefficient: -515.14; 95% CI: -986.06, -41.22; P = 0.03). Exclusive breastfeeding at 4-6 wk of age may have long-term effects on child health as evidenced by longer TL at 4 and 5 y of age. © 2016 American Society for Nutrition.

Colloidal thallium halide nanocrystals with reasonable luminescence, carrier mobility and diffusion length† †Electronic supplementary information (ESI) available: Synthesis and additional characterization of nanocrystals, characterization of nanocrystal films, temperature-dependent phase transition, coefficient of volume expansion, PL decay dynamics, tabulated best fit parameters, and methodology analysis of ultrafast optical pump THz probe (OPTP) spectroscopy. See DOI: 10.1039/c7sc01219e Click here for additional data file.

PubMed Central

Mir, Wasim J.; Warankar, Avinash; Acharya, Ashutosh; Das, Shyamashis

2017-01-01

Colloidal lead halide based perovskite nanocrystals (NCs) have been recently established as an interesting class of defect-tolerant NCs with potential for superior optoelectronic applications. The electronic band structure of thallium halides (TlX, where X = Br and I) show a strong resemblance to lead halide perovskites, where both Pb2+ and Tl+ exhibit a 6s2 inert pair of electrons and strong spin–orbit coupling. Although the crystal structure of TlX is not perovskite, the similarities of its electronic structure with lead halide perovskites motivated us to prepare colloidal TlX NCs. These TlX NCs exhibit a wide bandgap (>2.5 eV or <500 nm) and the potential to exhibit a reduced density of deep defect states. Optical pump terahertz (THz) probe spectroscopy with excitation fluence in the range of 0.85–5.86 × 1013 photons per cm2 on NC films shows that the TlBr NCs possess high effective carrier mobility (∼220 to 329 cm2 V–1 s–1), long diffusion length (∼0.77 to 0.98 μm), and reasonably high photoluminescence efficiency (∼10%). This combination of properties is remarkable compared to other wide-bandgap (>2.5 eV) semiconductor NCs, which suggests a reduction in the deep-defect states in the TlX NCs. Furthermore, the ultrafast carrier dynamics and temperature-dependent reversible structural phase transition together with its influence on the optical properties of the TlX NCs are studied. PMID:28970882

Telomerase activity, telomere length and hTERT DNA methylation in peripheral blood mononuclear cells from monozygotic twins with discordant smoking habits.

PubMed

Marcon, Francesca; Siniscalchi, Ester; Andreoli, Cristina; Allione, Alessandra; Fiorito, Giovanni; Medda, Emanuela; Guarrera, Simonetta; Matullo, Giuseppe; Crebelli, Riccardo

2017-10-01

Increased telomerase expression has been implicated in the pathogenesis of lung cancer and, since the primary cause of lung cancer is smoking, an association between telomerase reactivation and tobacco smoke has been proposed. In this work an investigation has been performed to assess the relationship between tobacco smoke exposure and telomerase activity (TA) in peripheral blood mononuclear cells of healthy smokers. The methylation status of the catalytic subunit of telomerase hTERT was concurrently investigated to assess the possible association between epigenetic modifications of hTERT and TA. Besides, the association between smoke and telomere length (TL) has been evaluated. Healthy monozygotic twins with discordant smoking habits were selected as study population to minimize inter-individual differences because of demographic characteristics and genetic heterogeneity. Statistically significant higher values of TA and TL were observed in smokers compared to nonsmoker co-twins. The multivariate analysis of data showed, besides smoking habits (P = 0.02), an influence of gender (P = 0.006) and BMI (P = 0.001) on TA and a borderline effect of gender (P = 0.05) on TL. DNA methylation analysis, focused on 100 CpG sites mapping in hTERT, highlighted nine CpG sites differentially methylated in smokers. When co-twins were contrasted, selecting as variables the intra-twin difference in TA and hTERT DNA methylation, a statistically significant inverse correlation (P = 0.003) was observed between TA and DNA methylation at the cg05521538 site. In conclusion, these results indicate an association of tobacco smoke with TA and TL and suggest a possible association between smoke-induced epigenetic effects and TA in healthy smokers. Environ. Mol. Mutagen. 58:551-559, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Number of Children and Telomere Length in Women: A Prospective, Longitudinal Evaluation

PubMed Central

Barha, Cindy K.; Hanna, Courtney W.; Salvante, Katrina G.; Wilson, Samantha L.; Robinson, Wendy P.; Altman, Rachel M.; Nepomnaschy, Pablo A.

2016-01-01

Life history theory (LHT) predicts a trade-off between reproductive effort and the pace of biological aging. Energy invested in reproduction is not available for tissue maintenance, thus having more offspring is expected to lead to accelerated senescence. Studies conducted in a variety of non-human species are consistent with this LHT prediction. Here we investigate the relationship between the number of surviving children born to a woman and telomere length (TL, a marker of cellular aging) over 13 years in a group of 75 Kaqchikel Mayan women. Contrary to LHT’s prediction, women who had fewer children exhibited shorter TLs than those who had more children (p = 0.045) after controlling for TL at the onset of the 13-year study period. An “ultimate” explanation for this apparently protective effect of having more children may lay with human’s cooperative-breeding strategy. In a number of socio-economic and cultural contexts, having more chilren appears to be linked to an increase in social support for mothers (e.g., allomaternal care). Higher social support, has been argued to reduce the costs of further reproduction. Lower reproductive costs may make more metabolic energy available for tissue maintenance, resulting in a slower pace of cellular aging. At a “proximate” level, mechanisms involved may include the actions of the gonadal steroid estradiol, which increases dramatically during pregnancy. Estradiol is known to protect TL from the effects of oxidative stress as well as increase telomerase activity, an enzyme that maintains TL. Future research should explore the potential role of social support as well as that of estradiol and other potential biological pathways in the trade-offs between reproductive effort and the pace of cellular aging within and among human as well as in non-human populations. PMID:26731744

Estimating geographic variation on allometric growth and body condition of Blue Suckers with quantile regression

USGS Publications Warehouse

Cade, B.S.; Terrell, J.W.; Neely, B.C.

2011-01-01

Increasing our understanding of how environmental factors affect fish body condition and improving its utility as a metric of aquatic system health require reliable estimates of spatial variation in condition (weight at length). We used three statistical approaches that varied in how they accounted for heterogeneity in allometric growth to estimate differences in body condition of blue suckers Cycleptus elongatus across 19 large-river locations in the central USA. Quantile regression of an expanded allometric growth model provided the most comprehensive estimates, including variation in exponents within and among locations (range = 2.88–4.24). Blue suckers from more-southerly locations had the largest exponents. Mixed-effects mean regression of a similar expanded allometric growth model allowed exponents to vary among locations (range = 3.03–3.60). Mean relative weights compared across selected intervals of total length (TL = 510–594 and 594–692 mm) in a multiplicative model involved the implicit assumption that allometric exponents within and among locations were similar to the exponent (3.46) for the standard weight equation. Proportionate differences in the quantiles of weight at length for adult blue suckers (TL = 510, 594, 644, and 692 mm) compared with their average across locations ranged from 1.08 to 1.30 for southern locations (Texas, Mississippi) and from 0.84 to 1.00 for northern locations (Montana, North Dakota); proportionate differences for mean weight ranged from 1.13 to 1.17 and from 0.87 to 0.95, respectively, and those for mean relative weight ranged from 1.10 to 1.18 and from 0.86 to 0.98, respectively. Weights for fish at longer lengths varied by 600–700 g within a location and by as much as 2,000 g among southern and northern locations. Estimates for the Wabash River, Indiana (0.96–1.07 times the average; greatest increases for lower weights at shorter TLs), and for the Missouri River from Blair, Nebraska, to Sioux City, Iowa (0.90–1.00 times the average; greatest decreases for lower weights at longer TLs), were examined in detail to explain the additional information provided by quantile estimates.

A genome-wide association study of limb bone length using a Large White × Minzhu intercross population.

PubMed

Zhang, Long-Chao; Li, Na; Liu, Xin; Liang, Jing; Yan, Hua; Zhao, Ke-Bin; Pu, Lei; Shi, Hui-Bi; Zhang, Yue-Bo; Wang, Li-Gang; Wang, Li-Xian

2014-11-04

In pig, limb bone length influences ham yield and body height to a great extent and has important economic implications for pig industry. In this study, an intercross population was constructed between the indigenous Chinese Minzhu pig breed and the western commercial Large White pig breed to examine the genetic basis for variation in limb bone length. The aim of this study was to detect potential genetic variants associated with porcine limb bone length. A total of 571 F2 individuals from a Large White and Minzhu intercross population were genotyped using the Illumina PorcineSNP60K Beadchip, and phenotyped for femur length (FL), humerus length (HL), hipbone length (HIPL), scapula length (SL), tibia length (TL), and ulna length (UL). A genome-wide association study was performed by applying the previously reported approach of genome-wide rapid association using mixed model and regression. Statistical significance of the associations was based on Bonferroni-corrected P-values. A total of 39 significant SNPs were mapped to a 11.93 Mb long region on pig chromosome 7 (SSC7). Linkage analysis of these significant SNPs revealed three haplotype blocks of 495 kb, 376 kb and 492 kb, respectively, in the 11.93 Mb region. Annotation based on the pig reference genome identified 15 genes that were located near or contained the significant SNPs in these linkage disequilibrium intervals. Conditioned analysis revealed that four SNPs, one on SSC2 and three on SSC4, showed significant associations with SL and HL, respectively. Analysis of the 15 annotated genes that were identified in these three haplotype blocks indicated that HMGA1 and PPARD, which are expressed in limbs and influence chondrocyte cell growth and differentiation, could be considered as relevant biological candidates for limb bone length in pig, with potential applications in breeding programs. Our results may also be useful for the study of the mechanisms that underlie human limb length and body height.

[Evaluation of left ventricular perfusion and regional wall motion in myocardial infarction: using 201Tl myocardial SPECT and 99mTc-HSAD multigated cardiac blood pool emission computed tomography].

PubMed

Nanjyo, S

1994-09-01

In order to evaluate left ventricular regional wall motion and regional myocardial perfusion, 99mTc-HSAD multigated cardiac blood pool emission computed tomography (cardiac pool SPECT) and 201Tl myocardial SPECT (Tl) were performed on 12 patients with acute myocardial infarction (AMI), 6 patients had treated with only thrombolysis in group I and 6 patients had treated with thrombolysis and selective PTCA in group II, 17 patients with old myocardial infarction (OMI) in group III and 5 normal volunteers (controls). The relationship between left ventricular regional wall motion and regional myocardial perfusion was estimated. The relationship between % length shortening (%LS) by cardiac pool SPECT and %Tl uptake (%TU) was good (r = 0.820) in group III. The value for %TU in the segments of akinesia was low (35%) and in the those of severe hypokinesia was higher (48%). In all phases, two groups showed significant relationships between %LS and %TU in group I and II. The %TU was unchanged in the akinetic segment, the %LS changed 30% in group I and the %LS changed to 49% in group II. If the %TU is more than 50% (AMI) or 40% (OMI), we would observe viable muscle. The combination of Tl and cardiac pool SPECT are useful for evaluating myocardial viability in the patients with AMI.

Individualized Internal and External Training Load Relationships in Elite Wheelchair Rugby Players.

PubMed

Paulson, Thomas A W; Mason, Barry; Rhodes, James; Goosey-Tolfrey, Victoria L

2015-01-01

The quantification and longitudinal monitoring of athlete training load (TL) provides a scientific explanation for changes in performance and helps manage injury/illness risk. Therefore, accurate and reliable monitoring tools are essential for the optimization of athletic performance. The aim of the present study was to establish the relationship between measures of internal [heart rate (HR) and session RPE (sRPE)] and external TL specific to wheelchair rugby (WR). Fourteen international WR athletes (age = 29 ± 7 years; body mass = 58.9 ± 10.9 kg) were monitored during 18 training sessions over a 3 month period during the competitive phase of the season. Activity profiles were collected during each training session using a radio-frequency based indoor tracking system (ITS). External TL was quantified by total distance (m) covered as well as time spent and distance covered in a range of classification-specific arbitrary speed zones. Banister's TRIMP, Edwards's summated HR zone (SHRZ), and Lucia's TRIMP methods were used to quantify physiological internal TL. sRPE was calculated as the product of session duration multiplied by perceived exertion using the Borg CR10 scale. Relationships between external and internal TL were examined using correlation coefficients and the 90% confidence intervals (90% CI). sRPE (r = 0.59) and all HR-based (r > 0.80) methods showed large and very large relationships with the total distance covered during training sessions, respectively. Large and very large correlations (r = 0.56 - 0.82) were also observed between all measures of internal TL and times spent and distances covered in low and moderate intensity speed zones. HR-based methods showed very large relationships with time (r = 0.71-0.75) and distance (r = 0.70-0.73) in the very high speed zone and a large relationship with the number of high intensity activities (HIA) performed (r = 0.56-0.62). Weaker relationships (r = 0.32-0.35) were observed between sRPE and all measures of high intensity activity. A large variation of individual correlation co-efficient was observed between sRPE and all external TL measures. The current findings suggest that sRPE and HR-based internal TL measures provide a valid tool for quantifying volume of external TL during WR training but may underestimate HIA. It is recommended that both internal and external TL measures are employed for the monitoring of overall TL during court-based training in elite WR athletes.

Individualized Internal and External Training Load Relationships in Elite Wheelchair Rugby Players

PubMed Central

Paulson, Thomas A. W.; Mason, Barry; Rhodes, James; Goosey-Tolfrey, Victoria L.

2015-01-01

Aim: The quantification and longitudinal monitoring of athlete training load (TL) provides a scientific explanation for changes in performance and helps manage injury/illness risk. Therefore, accurate and reliable monitoring tools are essential for the optimization of athletic performance. The aim of the present study was to establish the relationship between measures of internal [heart rate (HR) and session RPE (sRPE)] and external TL specific to wheelchair rugby (WR). Methods: Fourteen international WR athletes (age = 29 ± 7 years; body mass = 58.9 ± 10.9 kg) were monitored during 18 training sessions over a 3 month period during the competitive phase of the season. Activity profiles were collected during each training session using a radio-frequency based indoor tracking system (ITS). External TL was quantified by total distance (m) covered as well as time spent and distance covered in a range of classification-specific arbitrary speed zones. Banister's TRIMP, Edwards's summated HR zone (SHRZ), and Lucia's TRIMP methods were used to quantify physiological internal TL. sRPE was calculated as the product of session duration multiplied by perceived exertion using the Borg CR10 scale. Relationships between external and internal TL were examined using correlation coefficients and the 90% confidence intervals (90% CI). Results: sRPE (r = 0.59) and all HR-based (r > 0.80) methods showed large and very large relationships with the total distance covered during training sessions, respectively. Large and very large correlations (r = 0.56 − 0.82) were also observed between all measures of internal TL and times spent and distances covered in low and moderate intensity speed zones. HR-based methods showed very large relationships with time (r = 0.71−0.75) and distance (r = 0.70−0.73) in the very high speed zone and a large relationship with the number of high intensity activities (HIA) performed (r = 0.56−0.62). Weaker relationships (r = 0.32−0.35) were observed between sRPE and all measures of high intensity activity. A large variation of individual correlation co-efficient was observed between sRPE and all external TL measures. Conclusion: The current findings suggest that sRPE and HR-based internal TL measures provide a valid tool for quantifying volume of external TL during WR training but may underestimate HIA. It is recommended that both internal and external TL measures are employed for the monitoring of overall TL during court-based training in elite WR athletes. PMID:26733881

Totally laparoscopic gallbladder-preserving surgery: A minimally invasive and favorable approach for cholelithiasis.

PubMed

Gao, DE-Kang; Wei, Shao-Hua; Li, Wei; Ren, Jie; Ma, Xiao-Ming; Gu, Chun-Wei; Wu, Hao-Rong

2015-02-01

The aim of the present study was to investigate the effectiveness of laparoscopic gallbladder-preserving surgery (L-GPS) for cholelithiasis and the feasibility and value of totally laparoscopic GPS (TL-GPS). A total of 517 patients underwent L-GPS, including 365 cases of laparoscopy-assisted GPS (LA-GPS), 143 cases of TL-GPS (preservation rate, 98.3%) and nine conversions to laparoscopic cholecystectomy. The surgeries were all performed by one medical team and the mean operating time was 72 min. All macroscopic calculi were removed through endoscopy. The number of calculi observed in the patients was between one and several dozen; diameters ranged between 0.1 and 2.5 cm. Only three cases of incisional infection were noted in the LA-GPS group and long-term follow-up showed a low recurrence rate of 1.2%. L-GPS is, therefore, an excellent approach to cure cholelithiasis and TL-GPS is a feasible and effective option that could avoid incisional complications.

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

Wolfe, M.; Norman, D.

Birds and mammals exposed to waterborne mercury (Hg) and methylmercury (MeHg) were collected and/or sampled at Clear Lake, California, USA, to field test the predictive wildlife criteria model developed for the Great Lakes Water Quality Initiative (GLWQI). Tissue samples collected from sampled animals were analyzed for Hg and organochlorine residues, and for selected physiologic parameters known to be affected by Hg. All mammalian organ tissues analyzed contained less than 12 ppm total Hg, wet weight. All avian tissue samples analyzed contained less than 3 ppm total Hg, wet weight. No evidence of Hg-associated health effects was found. Tissue Hg residuesmore » were compared with water, sediment, and animal food samples to characterize bioaccumulation of mercury in the Clear Lake food web. Total Hg bioaccumulation factors for the Clear Lake site closest to the Hg source were: TL-2: 11,100; TL-3: 31,200; TL-4, 190,000. The results support the final wildlife criterion and suggest that the GLWQI model, with site-specific modifications, is predictive for other Hg-bearing aquatic systems.« less

Dosimetric characteristics of fabricated silica fibre for postal radiotherapy dose audits

NASA Astrophysics Data System (ADS)

Fadzil, M. S. Ahmad; Ramli, N. N. H.; Jusoh, M. A.; Kadni, T.; Bradley, D. A.; Ung, N. M.; Suhairul, H.; Mohd Noor, N.

2014-11-01

Present investigation aims to establish the dosimetric characteristics of a novel fabricated flat fibre TLD system for postal radiotherapy dose audits. Various thermoluminescence (TL) properties have been investigated for five sizes of 6 mol% Ge-doped optical fibres. Key dosimetric characteristics including reproducibility, linearity, fading and energy dependence have been established. Irradiations were carried out using a linear accelerator (linac) and a Cobalt-60 machine. For doses from 0.5 Gy up to 10 Gy, Ge-doped flat fibres exhibit linearity between TL yield and dose, reproducible to better than 8% standard deviation (SD) following repeat measurements (n = 3). For photons generated at potentials from 1.25 MeV to 10 MV an energy-dependent response is noted, with a coefficient of variation (CV) of less than 40% over the range of energies investigated. For 6.0 mm length flat fibres 100 μm thick × 350 pm wide, the TL fading loss following 30 days of storage at room temperature was < 8%. The Ge-doped flat fibre system represents a viable basis for use in postal radiotherapy dose audits, corrections being made for the various factors influencing the TL yield.

Prenatal stress from trawl capture affects mothers and neonates: a case study using the southern fiddler ray (Trygonorrhina dumerilii)

NASA Astrophysics Data System (ADS)

Guida, L.; Awruch, C.; Walker, T. I.; Reina, R. D.

2017-04-01

Assessing fishing effects on chondrichthyan populations has predominantly focused on quantifying mortality rates. Consequently, sub-lethal effects of capture stress on the reproductive capacity of chondrichthyans are largely unknown. We investigated the reproductive consequences of capture on pregnant southern fiddler rays (Trygonorrhina dumerilii) collected from Swan Bay, Australia, in response to laboratory-simulated trawl capture (8 h) followed immediately by air exposure (30 min). Immediately prior to, and for up to 28 days post trawling, all females were measured for body mass (BM), sex steroid concentrations (17-β estradiol, progesterone, testosterone) and granulocyte to lymphocyte (G:L) ratio. At parturition, neonates were measured for total length (TL), BM and G:L ratio. Trawling reduced maternal BM and elevated the G:L ratio for up to 28 days. Trawling did not significantly affect any sex steroid concentrations relative to controls. Neonates from trawled mothers were significantly lower in BM and TL than control animals, and had an elevated G:L ratio. Our results show that capture of pregnant T. dumerilii can influence their reproductive potential and affect the fitness of neonates. We suggest other viviparous species are likely to be similarly affected. Sub-lethal effects of capture, particularly on reproduction, require further study to improve fisheries management and conservation of chondrichthyans.

Mnemiopsis leidyi in the northern Adriatic: here to stay?

NASA Astrophysics Data System (ADS)

Malej, A.; Tirelli, V.; Lučić, D.; Paliaga, P.; Vodopivec, M.; Goruppi, A.; Ancona, S.; Benzi, M.; Bettoso, N.; Camatti, E.; Ercolessi, M.; Ferrari, C. R.; Shiganova, T.

2017-06-01

Mnemiopsis leidyi has successfully made the transition from its native spatial range along the Atlantic coast of North and South America to many areas of the Eurasian seas. In summer 2016, we observed M. leidyi at several sites within the northern Adriatic (Mediterranean Sea). Here we describe the spatio-temporal distribution of this invasive ctenophore and its morphological and biometric characteristics, and we present laboratory data on egg production and microscopic observations. M. leidyi was observed in the offshore, coastal and lagoon systems of the northern Adriatic, at temperatures ranging from 13 °C to 29 °C and salinity from 11 and 38, from July to December 2016. Dense blooms were detected intermittently from mid-August to November 2016. Total length (TL) of M. leidyi ranged from 2.0 to 13.5 cm with overall dominance (68.9 ± 14.2%) of the 5-9 cm size fraction. In the eastern part of the northern Adriatic, we always observed individuals with TL < 3 cm from August to November and cydippid larvae were found in net samples indicating successful reproduction throughout the studied period. Egg production under laboratory conditions (temperature 20-22 °C, salinity 37-38) was high, with mean of 4320 ± 3980 eggs ind.- 1 day- 1 and maximum of 13,512 eggs ind.- 1 day- 1.

Captive propagation, reproductive biology, and early life history of the Diamond Darter (Crystallaria cincotta)

USGS Publications Warehouse

Ruble, Crystal L.; Rakes, Patrick L.; Shute, John R.; Welsh, Stuart A.

2014-01-01

Reproductive biology and early life history data are critical for the conservation and management of rare fishes. During 2008–2012 a captive propagation study was conducted on the Diamond Darter, Crystallaria cincotta, a rare species with a single extant population in the lower Elk River, West Virginia. Water temperatures during spawning ranged from 11.1–23.3 C. Females and males spawned with quick vibrations, burying eggs in fine sand in relatively swift clean depositional areas. Egg size was 1.8–1.9 mm, and embryos developed within 7 to 11 d. Diamond Darters were 6.7–7.2 mm total length (TL) at hatch. Larvae ranged from 9.0–11.0 mm TL following a 5–10 d period of yolk sac absorption. Larvae had relatively large mouth gapes and teeth and were provided brine shrimp Artemia sp., Ceriodaphnia dubia neonates, marine Brachionus rotifers, and powdered foods (50–400 µm) but did not appear to feed in captivity, except for one observation of larval cannibalization. Larvae survived for a maximum of 10 d. To increase larval survival and reduce the possibility of cannibalism, other alternative food sources are needed during captive propagation.

The potential of using thermoluminescence to date buried soils developed on colluvial and fluvial sediments from Utah and Colorado, U.S.A.: Preliminary results

NASA Astrophysics Data System (ADS)

Forman, S. L.; Jackson, M. E.; McCalpin, J.; Maat, P.

The natural TL intensity for surface and buried Holocene and Pleistocene A horizons developed on flood-plain silts, near Denver, Colorado exponentially decreases with time. This signal is approaching saturation by ca. 130 ka. The A horizon of the modern flood-plain soil is not fully light bleached. The TL properties and age estimates are presented for radiocarbon dated, eolian-enriched buried-A horizons developed on fault-derived colluvium from the American Fork segment of the Wasatch fault zone, Utah. Dating of these buried soils provide a close age estimate on paleoearthquake events. Mean TL age estimates by regeneration and total bleach techniques for buried A horizons are 0.5 ± 0.1 ka and 2.7 ± 0.4 ka which are in agreement with corresponding radiocarbon dates of 980 ± 70 years BP and 2620 ± 70 years BP. A surface sag pond mud formed within an antithetic grabben is well light bleached and yielded a TL age estimate by the total bleach method of 240 ± 60 years BP, in agreement with its known age of <300 years BP. This study indicates that relatively brief periods of pedogenesis are not sufficient to light-bleach sediment and that eolian additions enhance the reduction of TL in soils.

Evaluation of life quality, self-confidence and sexual functions in patients with total and partial laryngectomy.

PubMed

Batıoğlu-Karaaltın, Ayşegül; Binbay, Zerrin; Yiğit, Özgür; Dönmez, Zehra

2017-04-01

In this study patients who have undergone partial (PL) or total laryngectomy (TL) were evaluated for life quality, self-esteem and sexual dysfunctions. 108 patients who received TL or PL without tracheostoma were included in this study. During patient interview, sociodemographical data form, European Organization for Research and Treatment of Cancer, Life Questionnaire Core 30 Items, Cancer and Head and Neck module-35 Items (EORTC QLQ-C30 and H&N35) were filled and patients were also asked to fill in Arizona Sexual Experiences Scale (ASEX), Beck's Depression Inventory (BDI), Beck's Anxiety Inventory (BAI) and Rosenberg Self-Esteem Scale (RSES) forms. Depression and anxiety scores and points taken from RSES were significantly different between TL and PL patients (p=0.045, p=0.041 and p=0.006 respectively). Although the difference was not significant in ASEX (p=0.174), the average scores of sexuality subunit (QL-35 59-60) of EORTC QLQ-H&N35 module were significantly different in these patients (p<0.001). Besides, it was shown that 90.3% of TL patients and 63.9% of PL patients have experienced negative effects in sexual functions. TL patients were more often observed to have problems regarding depression, anxiety, self-esteem and sexual functions and it is concluded that they may need psychosocial support more than PL patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Crash test and MASH TL-3 evaluation of the TxDOT short radius guardrail.

DOT National Transportation Integrated Search

2015-03-01

When a roadway intersects a highway with restrictive features such as a bridge rail and canal, it : becomes difficult to fit a guardrail with the proper length, transitions, and end treatment along the highway. : Possible solutions include relocating...

Study of the dairy characters of lactating Murrah buffaloes on the basis of body parts measurements

PubMed Central

Dhillod, Sandeep; Kar, Dipankar; Patil, C. S.; Sahu, Subhasish; Singh, Narender

2017-01-01

Aim: The aim of the study was to correlate the milk yield of Murrah buffaloes with certain body parts measurements. Materials and Methods: A total of 70 lactating Murrah buffaloes were selected from Buffalo Farm, Lala Lajpat Rai University of Veterinary and Animal Science, Hisar and were randomly selected in a range from first to fifth parity. Traits studied were 305 days milk yield (MY), body weight (BW), body length (BL), muzzle width (MW), height at wither (HW), abdominal girth (AG), chest girth (CG), body depth fore, body depth rear, hip bone distance (HBD), pin bone distance (PBD), skin thickness (STK), and tail length (TL). Data were collected and statically analyzed by Pearson’s correlation method. Result: The result of this study showed that Murrah buffaloes had the average 2604.8±39.5 kg for MY, 556.1±4.9 kg for BW, and 152.2±0.8 cm for BL. This study showed that buffaloes had positive significant (p<0.05) correlation between MY and BW (0.26). Highly significant (p<0.01) correlation was observed between MY and AG (0.64), MW (0.42). Significant (p<0.01) negative correlation was observed between MY and STK (−0.79). Different body part measurements (BW, BL, HW, AG, CG, MW, TL, BD, PBD, HBD, STK) were significantly correlated with each other. Conclusion: This study can be helpful as a selection tool to enhance and evaluate the production potential by setting standards of Murrah buffalo breed. BW, abdominal growth, muzzle thickness, and STK were found key factors while selecting a dairy Murrah buffalo. PMID:28246443

Thermoluminescence due to tunneling in nanodosimetric materials: A Monte Carlo study

NASA Astrophysics Data System (ADS)

Pagonis, Vasilis; Truong, Phuc

2018-02-01

Thermoluminescence (TL) signals from nanodosimetric materials have been studied extensively during the past twenty years, especially in the area of nanomaterials doped with rare earths. One of the primary effects being studied experimentally have been possible correlations between the nanocrystal size and the shape and magnitude of TL signals. While there is an abundance of experimental studies attempting to establish such correlations, the underlying mechanism is not well understood. This paper is a Monte Carlo simulation study of the effect of nanocrystal size on the TL signals, for materials in which quantum tunneling is the dominant recombination mechanism. TL signals are simulated for a random distribution of electrons and positive ions, by varying the following parameters in the model: the radius of the crystal R, tunneling length a, and the relative concentrations of electrons and ions. The simulations demonstrate that as the radius of the nanocrystals becomes larger, the peaks of the TL glow curves shift towards lower temperatures and changes occur in both peak intensity and peak width. For large crystals with a constant density of positive ions, the TL glow curves reach the analytical limit expected for bulk materials. The commonly used assumption of nearest neighbor interactions is examined within the model, and simulated examples are given in which this assumption breaks down. It is demonstrated that the Monte Carlo method presented in this paper can also be used for linearly modulated infrared stimulated luminescence (LM-IRSL) signals, which are of importance in luminescence dosimetry and luminescence dating applications. New experimental data are presented for Durango apatite, a material which is known to exhibit strong anomalous fading due to tunneling; the experimental data is compared with the model. The relevance of the simulated results for luminescence dosimetry is discussed.

A comparison of methods to quantify the in-season training load of professional soccer players.

PubMed

Scott, Brendan R; Lockie, Robert G; Knight, Timothy J; Clark, Andrew C; Janse de Jonge, Xanne A K

2013-03-01

To compare various measures of training load (TL) derived from physiological (heart rate [HR]), perceptual (rating of perceived exertion [RPE]), and physical (global positioning system [GPS] and accelerometer) data during in-season field-based training for professional soccer. Fifteen professional male soccer players (age 24.9 ± 5.4 y, body mass 77.6 ± 7.5 kg, height 181.1 ± 6.9 cm) were assessed in-season across 97 individual training sessions. Measures of external TL (total distance [TD], the volume of low-speed activity [LSA; <14.4 km/h], high-speed running [HSR; >14.4 km/h], very high-speed running [VHSR; >19.8 km/h], and player load), HR and session-RPE (sRPE) scores were recorded. Internal TL scores (HR-based and sRPE-based) were calculated, and their relationships with measures of external TL were quantified using Pearson product-moment correlations. Physical measures of TD, LSA volume, and player load provided large, significant (r = .71-.84; P < .01) correlations with the HR-based and sRPE-based methods. Volume of HSR and VHSR provided moderate to large, significant (r = .40-.67; P < .01) correlations with measures of internal TL. While the volume of HSR and VHSR provided significant relationships with internal TL, physical-performance measures of TD, LSA volume, and player load appear to be more acceptable indicators of external TL, due to the greater magnitude of their correlations with measures of internal TL.

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity.

PubMed

Tippett, Michael K; Cohen, Joel E

2016-02-29

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from 'outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954-2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related.

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity

PubMed Central

Tippett, Michael K.; Cohen, Joel E.

2016-01-01

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from ‘outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954–2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related. PMID:26923210

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity

NASA Astrophysics Data System (ADS)

Tippett, Michael K.; Cohen, Joel E.

2016-02-01

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from `outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954-2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related.

Self-assembly of thin, triangular prisms into open networks at a flat air-water interface

NASA Astrophysics Data System (ADS)

Solomon, Michael; Ferrar, Joseph; Bedi, Deshpreet; Zhou, Shangnan; Mao, Xiaoming

We observe capillary-driven binding between thin, equilateral triangle microprisms at a flat air-water interface. The triangles are fabricated from epoxy resin via SU-8 photolithography. For small thickness to length (T/L) ratios, two distinct pairwise particle-particle binding events occur with roughly equal frequency, and optical and environmental scanning electron microscopy (eSEM) demonstrate that these two distinct binding events are driven by the specific manner in which the interface is pinned to the particle surface. Additionally, particle bending is observed for the lowest T/L ratios, which leads to enhanced interface curvature and thus enhanced strength of capillary-driven attractions, and may also play a pivotal role in the dichotomy in particle-particle binding. Dichotomy in particle-particle binding is not observed at thicker T/L ratios, although capillary-driven binding still occurs. Ultimately, the particles self-assemble into space-spanning open networks, and the results suggest design parameters for the fabrication of building blocks of ordered open structures, such as the Kagome lattice.

Evidence for a pre-existing telomere deficit in non-clonal hematopoietic stem cells in patients with acute myeloid leukemia.

PubMed

Ventura Ferreira, Mónica S; Crysandt, Martina; Ziegler, Patrick; Hummel, Sebastian; Wilop, Stefan; Kirschner, Martin; Schemionek, Mirle; Jost, Edgar; Wagner, Wolfgang; Brümmendorf, Tim H; Beier, Fabian

2017-09-01

Telomere shortening represents an established mechanism connecting aging and cancer development. We sequentially analyzed telomere length (TL) of 49 acute myeloid leukemia (AML) patients at diagnosis (n = 24), once they achieved complete cytological remission (CCR) and/or during refractory disease or relapse and after 1-year follow-up, with all patients having at least two sequential samples. TL was analyzed by monochrome multiplex quantitative polymerase chain reaction. We have observed substantially shortened TL in the cells of patients at diagnosis compared to age-adjusted controls. In patients reaching CCR after chemotherapy, telomere shortening was less pronounced than in persistence or relapse but still significantly shortened compared to controls. We estimate patients harboring approximately 20 years of premature telomere loss compared to healthy aged-matched subjects at the time of AML onset. Our data indicate a pre-existing telomere deficit in non-clonal hematopoiesis of AML patients providing a link between age and AML development.

Development of the low-field side reflectometer for ITER

NASA Astrophysics Data System (ADS)

Muscatello, Christopher; Anderson, James; Gattuso, Anthony; Doyle, Edward; Peebles, William; Seraydarian, Raymond; Wang, Guiding; Kramer, Gerrit; Zolfaghari, Ali; Atomics Team, General; University of California Los Angeles Team; Princeton Plasma Physics Laboratory Team

2017-10-01

The Low-Field Side Reflectometer (LFSR) for ITER will provide real-time edge density profiles every 10 ms for feedback control and every 24 μs for physics evaluation. The spatial resolution will be better than 5 mm over 30 - 165 GHz, probing the scrape-off layer to the top of the pedestal in H-mode plasmas. An antenna configuration has been selected for measurements covering anticipated plasma elevations. Laboratory validation of diagnostic performance is underway using a LFSR transmission line (TL) mockup. The 40-meter TL includes circular corrugated waveguide, length calibration feature, Gaussian telescope, vacuum windows, containment membranes, and expansion joint. Transceiver modules coupled to the input of the TL provide frequency-modulated (FM) data for evaluation of performance as a monostatic reflectometer. Results from the mockup tests are presented and show that, with some further optimization, the LFSR will meet or exceed the measurement requirements for ITER. An update of the LFSR instrumentation design status is also presented with preliminary test results. Work supported by PPPL under subcontract S013252-A.

Disrupted lymphocyte homeostasis in hepatitis‐associated acquired aplastic anemia is associated with short telomeres

PubMed Central

Babushok, Daria V.; Grignon, Anne‐Laure; Li, Yimei; Atienza, Jamie; Xie, Hongbo M.; Lam, Ho‐Sun; Hartung, Helge; Bessler, Monica

2016-01-01

Hepatitis‐associated aplastic anemia (HAA) is a variant of acquired aplastic anemia (AA) in which immune‐mediated bone marrow failure (BMF) develops following an acute episode of seronegative hepatitis. Dyskeratosis congenita (DC) is an inherited BMF syndrome characterized by the presence of short telomeres, mucocutaneous abnormalities, and cancer predisposition. While both conditions may cause BMF and hepatic impairment, therapeutic approaches are distinct, making it imperative to establish the correct diagnosis. In clinical practice, lymphocyte telomere lengths (TL) are used as a first‐line screen to rule out inherited telomeropathies before initiating treatment for AA. To evaluate the reliability of TL in the HAA population, we performed a retrospective analysis of TL in 10 consecutively enrolled HAA patients compared to 19 patients with idiopathic AA (IAA). HAA patients had significantly shorter telomeres than IAA patients (P = 0.009), including four patients with TL at or below the 1st percentile for age‐matched controls. HAA patients had no clinical features of DC and did not carry disease‐causing mutations in known genes associated with inherited telomere disorders. Instead, short TLs were significantly correlated with severe lymphopenia and skewed lymphocyte subsets, features characteristic of HAA. Our results indicate the importance of caution in the interpretation of TL measurements in HAA, because, in this patient population, short telomeres have limited specificity. Am. J. Hematol. 91:243–247, 2016. © 2015 The Authors. American Journal of Hematology Published by Wiley Periodicals, Inc. PMID:26615915

Braided nanofibrous scaffold for tendon and ligament tissue engineering.

PubMed

Barber, John G; Handorf, Andrew M; Allee, Tyler J; Li, Wan-Ju

2013-06-01

Tendon and ligament (T/L) injuries present an important clinical challenge due to their intrinsically poor healing capacity. Natural healing typically leads to the formation of scar-like tissue possessing inferior mechanical properties. Therefore, tissue engineering has gained considerable attention as a promising alternative for T/L repair. In this study, we fabricated braided nanofibrous scaffolds (BNFSs) as a potential construct for T/L tissue engineering. Scaffolds were fabricated by braiding 3, 4, or 5 aligned bundles of electrospun poly(L-lactic acid) nanofibers, thus introducing an additional degree of flexibility to alter the mechanical properties of individual scaffolds. We observed that the Young's modulus, yield stress, and ultimate stress were all increased in the 3-bundle compared to the 4- and 5-bundle BNFSs. Interestingly, acellular BNFSs mimicked the normal tri-phasic mechanical behavior of native tendon and ligament (T/L) during loading. When cultured on the BNFSs, human mesenchymal stem cells (hMSCs) adhered, aligned parallel to the length of the nanofibers, and displayed a concomitant realignment of the actin cytoskeleton. In addition, the BNFSs supported hMSC proliferation and induced an upregulation in the expression of key pluripotency genes. When cultured on BNFSs in the presence of tenogenic growth factors and stimulated with cyclic tensile strain, hMSCs differentiated into the tenogenic lineage, evidenced most notably by the significant upregulation of Scleraxis gene expression. These results demonstrate that BNFSs provide a versatile scaffold capable of supporting both stem cell expansion and differentiation for T/L tissue engineering applications.

Variation in the life-history traits of a Schilbid catfish, Clupisoma garua (Hamilton, 1822) in the coastal waters of southern Bangladesh

NASA Astrophysics Data System (ADS)

Siddik, Muhammad Abu Bakar; Chaklader, Md Reaz; Hanif, Md Abu; Nahar, Ashfaqun; Ilham, Ilham; Cole, Anthony; Fotedar, Ravi

2017-09-01

For the first time, the present study reports the life-history traits, comprising length-frequency distribution (LFD), sex ratio (SR), length-weight relationships (LWRs), condition factors (CFs), and relative growth ( W R), of Clupisoma garua in the coastal waters of Bangladesh. A total of 150 specimens ranging from 8.60 to 25.20 cm total length (TL) and 4.26 to 128.80 g body weight (BW) were collected using traditional fishing gear from August 2013 to July 2014. The overall sex ratio of males to females in the study did not differ significantly from the expected value of 1:1 (χ2 =0.96, P <0.05) but there were significant sex differences ( P <0.05) in the intercepts and slopes of graphs characterizing traits in C. garua. The calculated b values for the LWRs were 2.955, 2.893 and 2.927 for males, females and combined sexes, respectively, and there was negative allometric growth in all cases ( b <3). The condition factors ( K A , K F , K R ) and relative growth ( W R ) also did not differ significantly ( P <0.05) between the sexes. This study provides a useful tool for fishery specialists to evaluate the relative condition of fish and to initiate early management strategies and regulations for the sustainable management of the remaining stocks of this species in the entire coastal region of southern Bangladesh.

A study of anatomy of distal femur pertaining to total knee replacement: an analysis, conclusions and recommendations.

PubMed

Kumar, K; Sharma, D

2018-04-01

Multiple landmarks including the transepicondylar axis (TEA), posterior condylar axis (PCA) and anterior trochlear line (TL) have been used to set up the femoral component rotation, but each is faced with its own practical obstacle that limits its usage. Also a common practice is to set the femoral component rotation at 3° external rotation to PCA and valgus resection angle at 5°-7° to anatomical axis of femur. For the reason that the anatomy of each knee is different, it may not be justified to practice such a set protocol in all cases. The aim of the study was to compare the anatomical landmarks used to set up the femoral component rotation and to study the variability in the different anatomical relationships relevant to total knee replacement. The study had 52 patients (94 knees) with grade IV osteoarthritis. Full-length lower limb scanogram and 1 mm cross-sectional cuts of distal femur were taken. aTEA, sTEA, PCL, TL, CTA, PCA, TLA and valgus angles were taken for all knees. aTEA is identifiable in all cases but sTEA in only 59 knees (62.77%). Correspondingly, CTA is calculable in all knees and PCA in 62.77% cases. Mean CTA and mean PCA were 5.4° ± 1.88° SD and 0.71° ± 1.95° SD, respectively. Mean angle between aTEA and sTEA was 4.88. TL is a line difficult to draw because of high incidence of anterior osteophytes, making CTA a more reliable parameter than TLA. Mean TLA was 10.31° ± 3.52° SD. Mean valgus resection angle was 4.86° ± 2.53° SD. Gender- or side-based differences in any of these values were not statistically different. Using aTEA or sTEA can make a big difference in femoral component rotation; therefore, whether aTEA or sTEA should be used needs to be further investigated. CTA, PCA and valgus resection angle need to be individually calculated for each knee. Use of TLA is not recommended.

Thallium dispersal and contamination in surface sediments from South China and its source identification.

PubMed

Liu, Juan; Wang, Jin; Chen, Yongheng; Shen, Chuan-Chou; Jiang, Xiuyang; Xie, Xiaofan; Chen, Diyun; Lippold, Holger; Wang, Chunlin

2016-06-01

Thallium (Tl) is a non-essential element in humans and it is considered to be highly toxic. In this study, the contents, sources, and dispersal of Tl were investigated in surface sediments from a riverine system (the western Pearl River Basin, China), whose catchment has been contaminated by mining and roasting of Tl-bearing pyrite ores. The isotopic composition of Pb and total contents of Tl and other relevant metals (Pb, Zn, Cd, Co, and Ni) were measured in the pyrite ores, mining and roasting wastes, and the river sediments. Widespread contamination of Tl was observed in the sediments across the river, with the highest concentration of Tl (17.3 mg/kg) measured 4 km downstream from the pyrite industrial site. Application of a modified Institute for Reference Materials and Measurement (IRMM) sequential extraction scheme in representative sediments unveiled that 60-90% of Tl and Pb were present in the residual fraction of the sediments. The sediments contained generally lower (206)Pb/(207)Pb and higher (208)Pb/(206)Pb ratios compared with the natural Pb isotope signature (1.2008 and 2.0766 for (206)Pb/(207)Pb and (208)Pb/(206)Pb, respectively). These results suggested that a significant fraction of non-indigenous Pb could be attributed to the mining and roasting activities of pyrite ores, with low (206)Pb/(207)Pb (1.1539) and high (208)Pb/(206)Pb (2.1263). Results also showed that approximately 6-88% of Tl contamination in the sediments originated from the pyrite mining and roasting activities. This study highlights that Pb isotopic compositions could be used for quantitatively fingerprinting the sources of Tl contamination in sediments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Acculturation and environmental change impacts dietary habits among adult Hmong.

PubMed

Franzen, Lisa; Smith, Chery

2009-02-01

Focus groups (n=65) were conducted with Hmong adults in St. Paul/Minneapolis, MN to determine how environmental factors, acculturation, and food insecurity influence dietary behavior, body mass index (BMI), and health. Acculturation was assessed by examining linguistic, social, and eating behavior, length of time in the US, and BMI for B-TL(1) (born in Thailand/Laos and in US < or =5 years), B-TL(2) (in Thailand/Laos through adolescence, had food memories, and in US >5 years), and B-US (born in US or in Thailand/Laos less than 8 years and no food memories from there). Acculturation was associated with years lived in the US, household size and income, and food assistance usage. Years lived in the US was correlated with food assistance usage, education, household size and income, and perception of diet. B-TL(1) and B-TL(2) were on average overweight (BMI> or =25<30), US men were obese (mean BMI=32.4+/-7.4), and women were overweight (mean BMI=29.1+/-6.8). Themes identified were cultural values impact eating and lifestyle behaviors, food insecurity history influences post-migration behavior, acculturation impacts BMI through diet and exercise, and health status is influenced by changed environments. Environmental changes and increased acculturation have negatively impacted the weight and health of Hmong adults.

Selective disappearance of great tits with short telomeres in urban areas.

PubMed

Salmón, Pablo; Nilsson, Johan F; Watson, Hannah; Bensch, Staffan; Isaksson, Caroline

2017-09-13

Urban environments pose novel challenges, as well as opportunities, for urban-dwelling wildlife. Although differences have been reported in several phenotypic traits (e.g. morphology, physiology and behaviour) between urban and rural populations, it is poorly understood whether this affects individual fitness. Telomere dynamics are posited as one possible mechanism underlying senescence and mortality. It was recently shown that telomere shortening is accelerated when growing up in an urban, compared with a rural, environment. However, the implications of accelerated telomere attrition for fitness are still unclear. Here, we examine the relationship between telomere length (TL) and survival in a bird common to urban and rural environments, and during both early and later life. The results reveal that TL is a strong predictor of post-fledging survival and recruitment in both habitats but, crucially, selective disappearance of individuals with short telomeres early in life is more pronounced in the urban environment, resulting in a longer average TL among the adult population. However, following recruitment, we found no difference in the relationship between TL and survival between the urban and rural environments. This indicates that the urban environment has negative effects in early life, while during later life the benefits could potentially outweigh the costs. © 2017 The Author(s).

PNacPNacE: (E = Ga, In, Tl) - monomeric group 13 metal(i) heterocycles stabilized by a sterically demanding bis(iminophosphoranyl)methanide.

PubMed

Sindlinger, Christian P; Lawrence, Samuel R; Acharya, Shravan; Ohlin, C André; Stasch, Andreas

2017-12-12

The salt metathesis reaction of the sterically demanding bis(iminophosphoranyl)methanide alkali metal complexes LM (L - = HC(Ph 2 P[double bond, length as m-dash]NDip) 2 - , Dip = 2,6- i Pr 2 C 6 H 3 ; M = Li, Na, K) with "GaI", InBr or TlBr afforded the monomeric group 13 metal(i) complexes LE:, E = Ga (1), In (2) and Tl (3) in moderate yields, and small quantities of LGaI 2 4 in the case of Ga, respectively. The molecular structures of LE: 1-3 from X-ray single crystal diffraction show them to contain puckered six-membered rings with N,N'-chelating methanide ligands and two-coordinated metal(i) centres. Reduction reactions of LAlI 2 5, prepared by iodination of LAlMe 2 , were not successful and no aluminium(i) congener could be prepared so far. DFT studies on LE:, E = Al-Tl, were carried out and support the formulation as an anionic, N,N'-chelating methanide ligand coordinating to group 13 metal(i) cations. The HOMOs of the molecules for E = Al-In show a dominant contribution from a metal-based lone pair that is high in s-character.

The Differential Impact of Oxytocin Receptor Gene in Violence-Exposed Boys and Girls

PubMed Central

Merrill, Livia C.; Jones, Christopher W.; Drury, Stacy S.; Theall, Katherine P.

2017-01-01

Childhood violence exposure is a prevalent public health problem. Understanding the lasting impact of violence requires an enhanced appreciation for the complex effects of violence across behavioral, physiologic, and molecular outcomes. This subject matched, cross-sectional study of 80 children explored the impact of violence exposure across behavioral, physiologic, and cellular outcomes. Externalizing behavior, diurnal cortisol rhythm, and telomere length (TL) were examined in a community recruited cohort of Black youth. Given evidence that genetic variation contributes to individual differences in response to the environment, we further tested whether a polymorphism in the oxytocin receptor gene (OXTR rs53576) moderated associations between violence and youth outcomes. Exposure to violence was directly associated with increased externalizing behavior, but no direct association of violence was found with cortisol or TL. Oxytocin genotype, however, moderated the association between violence and both cortisol and TL, suggesting that pathways linked to oxytocin may contribute to individual differences in the physiologic and molecular consequences of violence exposure. Sex differences with OXTR in cortisol and TL outcomes were also detected. Taken together, these findings suggest that there are complex pathways through which violence exposure impacts children, and that these pathways differ by both genetic variation and the sex of the child. PMID:28341538

The differential impact of oxytocin receptor gene in violence-exposed boys and girls.

PubMed

Merrill, Livia C; Jones, Christopher W; Drury, Stacy S; Theall, Katherine P

2017-06-01

Childhood violence exposure is a prevalent public health problem. Understanding the lasting impact of violence requires an enhanced appreciation for the complex effects of violence across behavioral, physiologic, and molecular outcomes. This subject matched, cross-sectional study of 80 children explored the impact of violence exposure across behavioral, physiologic, and cellular outcomes. Externalizing behavior, diurnal cortisol rhythm, and telomere length (TL) were examined in a community recruited cohort of Black youth. Given evidence that genetic variation contributes to individual differences in response to the environment, we further tested whether a polymorphism in the oxytocin receptor gene (OXTR rs53576) moderated associations between violence and youth outcomes. Exposure to violence was directly associated with increased externalizing behavior, but no direct association of violence was found with cortisol or TL. Oxytocin genotype, however, moderated the association between violence and both cortisol and TL, suggesting that pathways linked to oxytocin may contribute to individual differences in the physiologic and molecular consequences of violence exposure. Sex differences with OXTR in cortisol and TL outcomes were also detected. Taken together, these findings suggest that there are complex pathways through which violence exposure impacts children, and that these pathways differ by both genetic variation and the sex of the child. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.

Feeding ecology of some fish species occurring in artisanal fishery of Socotra Island (Yemen).

PubMed

Hassan Ali', Mohammed Kaed; Belluscio, Andrea; Ventura, Daniele; Ardizzone, Giandomenico

2016-04-30

The demersal species Lethrinus borbonicus, Lethrinus mahsena, Lethrinus microdon, Lethrinus nebulosus, Lutjanus bohar, Lutjanus gibbus, Lutjanus kasmira, Epinephelus fasciatus, Epinephelus stoliczkae, Carangoides gymnostethus and Euthynnus affinis are important coastal fishes species of the northern coast of Socotra (Yemen), exploited by local fishery. The biology and feeding ecology of these species are poorly known in the area. A total of 1239 specimens were sampled from the main fishing landing site of the island (Hadibo). Total length and weight were measured, stomach contents were analyzed, diet overlap, Fulton's Condition index, and trophic levels were estimated. C. gymnostethus, L. microdon and L. kasmira occupied the highest position (T=4.50), L. nebulosus occupied the lower one (TL=3.41). The role of the increasing abundance of small pelagic fish in the diet of many species after the upwelling event is evident, but also different feeding strategies are reported, according to fish ecology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Total mercury concentrations in fillets of bluegill, redear sunfish, largemouth bass, and other fishes from Lake Natoma, Sacramento County, California

USGS Publications Warehouse

Saiki, M.K.; Martin, B.A.; May, T.W.; Alpers, Charles N.

2005-01-01

This study was conducted during September-October 2002 to verify preliminary findings of elevated total mercury concentrations in skinless fillets of sportfishes inhabiting Lake Natoma. Although we measured total mercury concentrations, most mercury in fish flesh occurs in the methylated form. In August 2000, other investigators collected a small number of fish containing mercury concentrations that exceeded 0.30 ??g/g wet weight, the U.S. Environmental Protection Agency (USEPA) tissue residue criterion derived from a reference dose for methylmercury that may cause undesirable neurological abnormalities in human infants exposed in utero when pregnant women consume mercury-contaminated foods. During our study, skinless fillets of bluegill, Lepomis macrochirus, contained as much as 0.19 ??g Hg/g wet weight (1.06 ??g Hg/g dry weight); redear sunfish, L. microlophus, contained as much as 0.39 ??g Hg/g wetweight (1.99 ??g Hg/g dry weight); and largemouth bass, Micropterus salmoides, contained as much as 0.86 ??g Hg/g wet weight (3.85 ??g Hg/g dry weight). Maximum concentrations of mercury in other fish species varied from 0.097 ??g/g wet weight (0.537 ??g/g dry weight) in rainbow trout, Oncorhynchus mykiss, to 0.56 ??g/g wet weight (3.07 ??g/g dry weight) in white catfish, Ameiurus catus. Altogether, 1 of 20 redear sunfish, 14 of 61 largemouth bass, 1 of 1 brown builhead, A. nebulosus, 2 of 3 spotted bass, M. punctulatus, and 1 of 1 white catfish exceeded the USEPA fish tissue methylmercury residue criterion. Only bluegill and largemouth bass exhibited significant correlations between fish total length (TL), weight, and age, and total mercury concentration in fillets. Judging from a best-fit power-curve equation, largemouth bass measuring 273 mm TL (roughly 292g) or larger are estimated to contain total mercury concentrations in their fillets that exceed the USEPA fish tissue methylmercury criterion. These results confirmed that some fish species inhabiting Lake Natoma are contaminated with undesirably high concentrations of mercury in their skinless fillets.

Sleep, training load and performance in elite female gymnasts.

PubMed

Dumortier, J; Mariman, A; Boone, J; Delesie, L; Tobback, E; Vogelaers, D; Bourgois, J G

2018-03-01

Training load (TL) and recovery should be in optimal balance to obtain maximal performance gains. We aimed to study sleep as a recovery technique and its relationship with TL and performance in elite athletes. Twenty-six elite female artistic gymnasts were divided into an under 13 (n = 6), an under 14 (n = 6), a junior (n = 7; 14-15y) and a senior (=World Championship (WC) competitors, n = 7; ≥16y) category. Sleep, through sleep logs, and training parameters, using the session Rate of Perceived Exertion (sRPE) scale, were monitored to calculate total sleep time (TST), sleep efficiency (SE), TL, monotony and strain. Performance of WC competitors was evaluated through coach and WC qualification ranking. For the entire group, TST (effect sizes (ES) = -1.12, confidence intervals (CI) = -60:-47, P < .05) and SE (ES = -0.13, CI = -1.40:-0.10, P = .022) were shorter during week than weekend nights. TST and SE were highest in youngest gymnasts (P < .05). TL was lowest in under 13 and senior gymnasts (P < .05), while TL, monotony and strain were highest in junior gymnasts (P < .05). A negative regression was found between TST and TL the day after, while higher TL also led to lower TST the following night (P < .001). For the WC competitors, TST the night before the qualifications was shorter than the mean TST of the WC period (ES = -0.95, CI = -170:24, P = .030). TST correlated with coach ranking (r = -0.857, P = .014). Higher TL correlated with worse WC (r = 0.829, P = .042) and coach (r = 0.893, P = .007) ranking. This research in elite gymnasts indicated associations between decreased TST, augmented TL and inferior performance. Optimizing sleep and TL may therefore represent strategies to enhance performance.

Can CT imaging of the chest, abdomen, and pelvis identify all vertebral injuries of the thoracolumbar spine without dedicated reformatting?

PubMed

Imran, Jonathan B; Madni, Tarik D; Pruitt, Jeffrey H; Cornelius, Canon; Subramanian, Madhu; Clark, Audra T; Mokdad, Ali A; Rizk, Paul; Minei, Joseph P; Cripps, Michael W; Eastman, Alexander L

2018-07-01

The main objective of this study was to compare detection rates of clinically significant thoracolumbar spine (TLS) fracture between computed tomography (CT) imaging of the chest, abdomen, and spine (CT CAP) and CT for the thoracolumbar spine (CT TL). We retrospectively identified patients at our institution with a TLS fracture over a two-year period that had both CT CAP and reformatted CT TL imaging. The sensitivity of CT CAP to identify fracture was calculated for each fracture type. A total of 516 TLS fractures were identified in 125 patients using reformatted CT TL spine imaging. Overall, 69 of 512 fractures (13%) were missed on CT CAP that were identified on CT TL. Of those, there were no clinically significant missed fractures. CT CAP could potentially be used as a screening tool for clinically significant TLS injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

Perceptions of a continuing professional development portfolio model to enhance the scholarship of teaching and learning.

PubMed

Tofade, Toyin; Abate, Marie; Fu, Yunting

2014-04-01

To obtain feedback about the potential usefulness of a continuing professional development (CPD) portfolio for enhancing a faculty or practitioner's scholarship of teaching and learning (SoTL). A CPD portfolio approach to the SoTL was distributed in advance to registrants of the 2011 Annual AACP Teacher's Seminar. In an interactive workshop, faculty facilitators described a model for a CPD process applied to the development of an individual's SoTL. During the workshop, participants were asked to complete the initial sections of the portfolio to develop a personal plan for success in the SoTL. Post workshop, an evaluation form was distributed to the participants to obtain feedback about the CPD approach. Completed evaluation forms were collected, collated, and summarized. A total of 53 (14.1%) workshop participants completed the evaluation form of the 375 attendees. In all, 25 assistant professors, 14 associate professors, 4 full professors, 10 residents/students, 22 clinical, and 2 research faculty submitted evaluations. The proposed uses for the portfolio model selected most often by the responders were for personal development, faculty evaluation, increasing the SoTL, new faculty development, preceptor development, and residency training. A structured CPD portfolio model might be useful for the professional development of the SoTL.

Making it fit: Associations of line managers' behaviours with the outcomes of an organizational-level intervention.

PubMed

Lundmark, Robert; von Thiele Schwarz, Ulrica; Hasson, Henna; Stenling, Andreas; Tafvelin, Susanne

2018-02-01

Line managers' behaviours are important during implementation of occupational health interventions. Still, little is known about how these behaviours are related to intervention outcomes. This study explored the relationship between line managers' intervention-specific transformational leadership (IsTL), intervention fit (the match between the intervention, persons involved, and the surrounding environment), and change in intrinsic motivation and vigour. Both direct and indirect relationships between IsTL and change in intrinsic motivation and vigour were tested. Ninety employees participating in an organizational-level occupational health intervention provided questionnaire ratings at baseline and after 6 months. The results showed IsTL to be related to intervention fit and intervention fit to be related to intrinsic motivation. Using intervention fit as a mediator, the total effects (direct and indirect combined) of IsTL on change in intrinsic motivation and vigour were significant. In addition, IsTL had a specific indirect effect on intrinsic motivation. This study is the first to use IsTL as a measure line managers' behaviours. It is also the first to empirically evaluate the association between intervention fit and intervention outcomes. By including these measures in evaluations of organizational-level occupational health interventions, we can provide more informative answers as to what can make interventions successful. Copyright © 2017 John Wiley & Sons, Ltd.

The potential impact of biochemical mediators on telomere attrition in major depressive disorder and implications for future study designs: A narrative review.

PubMed

Manoliu, Andrei; Bosch, Oliver G; Brakowski, Janis; Brühl, Annette B; Seifritz, Erich

2018-01-01

Major depressive disorder (MDD) has been proposed to represent a "disease of premature aging", which is associated with certain biomarkers of cellular ageing and numerous other age-related diseases. Over the last decade, telomere length (TL) arose as a surrogate for cellular aging. Recent data suggests that TL might be reduced in patients with MDD, however, results are still inconclusive. This might be explained by the lack of assessment of potential biochemical mediators that are directly associated with telomere shortening and frequently observed in patients with MDD. A narrative review was performed. The PubMed database was searched for relevant studies. We identified four major mediators, which are recurrently reported in patients with MDD and are associated with reduced TL: inflammation/oxidative stress, dysregulation of the hypothalamic-pituitary-adrenal axis, metabolic dysbalance including insulin resistance, and decreased brain-derived neurotrophic factor. These mediators are also mutually associated and were not systematically assessed in current studies investigating TL and MDD, which might explain inconclusive findings across current literature. Finally, we discuss possible ways to assess those mediators and potential implications of such approaches for future research. The majority of identified studies had cross-sectional designs and used heterogeneous methods to assess TL and associated relevant biochemical mediators. A better understanding of the complex interactions between biochemical mediators, somatic comorbidities and shortened telomeres in patients with MDD might further specify the pathophysiology-based conceptualization and, based on that, personalized treatment of MDD. Copyright © 2017 Elsevier B.V. All rights reserved.

Low-Loss Infrared Fibers.

DTIC Science & Technology

1980-12-01

now apply similar methods to KRS-5, TlBr , etc. to obtain better fiber material. 11 * hi LI * I. * ec - ~-,-. - * 1~-, * . SECTION 2 TECHNICAL PROGRESS...TOTAL FRESNEL 3 3 LOSS 1.45 dB TlBr I x 10 (0.43) 1 x 10 (0.4 ) 0.2 KCI 8 X 10 - 5 (0.(35) . x 10- 2 (4.2) 0I S.0.5 1.0 15S KBr I x 10 - (0.0004

Radiopharmaceuticals for SPECT cancer detection

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

Chernov, V. I., E-mail: chernov@oncology.tomsk.ru; Medvedeva, A. A., E-mail: tickayaAA@oncology.tomsk.ru; Zelchan, R. V., E-mail: r.zelchan@yandex.ru

2016-08-02

The purpose of the study was to assess the efficacy of single photon emission computed tomography (SPECT) with {sup 199}Tl and {sup 99}mTc-MIBI in the detection of breast, laryngeal and hypopharyngeal cancers. A total of 220 patients were included into the study: 120 patients with breast lesions (100 patients with breast cancer and 20 patients with benign breast tumors) and 100 patients with laryngeal/hypopharyngeal diseases (80 patients with laryngeal/hypopharyngeal cancer and 20 patients with benign laryngeal/hypopharyngeal lesions). No abnormal {sup 199}Tl uptake was seen in all patients with benign breast and laryngeal lesions, indicating a 100% specificity of {sup 199}Tlmore » SPECT. In the breast cancer patients, the increased {sup 199}Tl uptake in the breast was visualized in 94.8% patients, {sup 99m}Tc-MIBI—in 93.4% patients. The increased {sup 199}Tl uptake in axillary lymph nodes was detected in 60% patients, and {sup 99m}Tc-MIBI—in 93.1% patients. In patients with laryngeal/hypopharyngeal cancer, the sensitivity of SPECT with {sup 199}Tl and {sup 99m}Tc-MIBI was 95%. The {sup 199}Tl SPECT sensitivity in identification of regional lymph node metastases in the patients with laryngeal/hypopharyngeal cancer was 75% and the {sup 99m}Tc-MIBI SPECT sensitivity was 17%. The data obtained showed that SPECT with {sup 199}Tl and {sup 99m}Tc-MIBI can be used as one of the additional imaging methods in detection of tumors.« less

Agkistrodon piscivorus conanti (Florida cottonmouth) Diet

USGS Publications Warehouse

Grajal-Puche, Alejandro; Josimovich, Jillian; Falk, Bryan; Reed, Robert

2016-01-01

Agkistrodon piscivorus is a generalist predator that feeds on a variety of prey, including snakes (Gloyd and Conant 1990. Snakes of the Agkistrodon Complex: A Monographic Review. Society for the Study of Amphibians and Reptiles, Oxford, Ohio. 614 pp.; Lillywhite et al. 2002. Herpetol. Rev. 33:259–260; Hill and Beaupre 2008. Copeia 2008:105–114). Cemophora coccinea (Scarletsnake) is not known as one of the 26 species of snakes consumed by A. piscivorus (Ernst and Ernst 2011. Venomous Reptiles of the United States, Canada, and Northern Mexico: Volume 1. Johns Hopkins University Press, Baltimore, Maryland. 193 pp.). On 16 June 2015, at 2210 h, we found a dead-on-road A. piscivorus (total length [TL] = 51.0 cm) in Everglades National Park on Main Park Road, 1.88 km S Pa-hay-okee, Miami-Dade Co., Florida, USA (25.414085°N, 80.78183146°W, WGS84; elev. 3 m). The snake had been killed by a vehicle and some internal organs were exposed. Visible stomach contents included a small (TL ca. 15 cm) C. coccinea. Photographic vouchers of the A. piscivorus (UF-Herpetology 177194) and C. coccinea (UF-Herpetology 177195) were deposited in the Division of Herpetology, Florida Museum of Natural History, University of Florida. Despite the fact that these species are sympatric over large areas of the southeastern United States, this is the first known documented predation of C. coccinea by A. piscivorus.

Ontogenesis of endangered humpback chub (Gila cypha) in the Little Colorado River, Arizona

USGS Publications Warehouse

Stone, Dennis M.; Gorman, Owen T.

2006-01-01

The largest population of endangered humpback chub Gila cypha inhabits the Colorado River below Glen Canyon Dam and the lower 14 km of the Little Colorado River (LCR), Arizona. Currently, adults from both rivers spawn and their progenies grow and recruit to adulthood primarily within the LCR, where we studied G. cypha's life history using hoop net capture data. Humpback chub undergo an ontogenesis from diurnally active, vulnerable, nearshore-reliant young-of-the-year (YOY; 30-90 mm total length) into nocturnally active, large-bodied adults (a?Y180 mm TL). During the day, adults primarily resided in deep midchannel pools; however, at night they dispersed inshore amongst the higher densities of YOY conspecifics. Many YOY G. cypha shifted to nocturnal habitats that provided greater cover, possibly, to avoid inshore invading adults. These findings mirror predator-prey scenarios described in other freshwater assemblages, but do not refute other plausible hypotheses. Gila cypha piscivorous activity may escalate in hoop nets, which can confine fish of disparate sizes together; adults were significantly associated with YOY conspecifics and small dead fish in hoop nets at night and eight G. cypha (156-372 mm TL) regurgitated and/or defecated other fish body parts during handling following capture. Gila cypha can definitely be piscivorous given the opportunity, but the magnitude of their piscivorous activity in the wild is debatable.

Prenatal stress from trawl capture affects mothers and neonates: a case study using the southern fiddler ray (Trygonorrhina dumerilii)

PubMed Central

Guida, L.; Awruch, C.; Walker, T. I.; Reina, R. D.

2017-01-01

Assessing fishing effects on chondrichthyan populations has predominantly focused on quantifying mortality rates. Consequently, sub-lethal effects of capture stress on the reproductive capacity of chondrichthyans are largely unknown. We investigated the reproductive consequences of capture on pregnant southern fiddler rays (Trygonorrhina dumerilii) collected from Swan Bay, Australia, in response to laboratory-simulated trawl capture (8 h) followed immediately by air exposure (30 min). Immediately prior to, and for up to 28 days post trawling, all females were measured for body mass (BM), sex steroid concentrations (17-β estradiol, progesterone, testosterone) and granulocyte to lymphocyte (G:L) ratio. At parturition, neonates were measured for total length (TL), BM and G:L ratio. Trawling reduced maternal BM and elevated the G:L ratio for up to 28 days. Trawling did not significantly affect any sex steroid concentrations relative to controls. Neonates from trawled mothers were significantly lower in BM and TL than control animals, and had an elevated G:L ratio. Our results show that capture of pregnant T. dumerilii can influence their reproductive potential and affect the fitness of neonates. We suggest other viviparous species are likely to be similarly affected. Sub-lethal effects of capture, particularly on reproduction, require further study to improve fisheries management and conservation of chondrichthyans. PMID:28401959

Reproductive biology of Raja clavata (Elasmobranchii: Rajidae) from Southern Black Sea coast around Turkey

NASA Astrophysics Data System (ADS)

Saglam, Hacer; Ak, Orhan

2012-06-01

Specimens of Raja clavata were monthly collected at the coast of Havaalanı (Trabzon/Turkey) from January 2009 to December 2009 at depths between 20 and 40 m. A total of 230 individuals of thornback ray (131 females and 99 males) were collected by bottom trawls during research cruises. Using logistic regression, it was determined that TL at 50% maturity of males was 718 mm TL and of females 746 mm TL. The ovarian fecundity ranged from 27 to 60 yellow follicles in both ovaries. Females carrying egg cases were found in July and October. Variations in the gonadosomatic and hepatosomatic indices indicated a continuous reproductive cycle during the year.

Prenatal omega-3 fatty acid supplementation does not affect offspring telomere length and F2-isoprostanes at 12 years: A double blind, randomized controlled trial.

PubMed

See, V H L; Mas, E; Burrows, S; O'Callaghan, N J; Fenech, M; Prescott, S L; Beilin, L J; Huang, R C; Mori, T A

2016-09-01

Oxidative stress and nutritional deficiency may influence the excessive shortening of the telomeric ends of chromosomes. It is known that stress exposure in intrauterine life can produce variations in telomere length (TL), thereby potentially setting up a long-term trajectory for disease susceptibility. To assess the effect of omega-3 long chain polyunsaturated fatty acid (n-3 LCPUFA) supplementation during pregnancy on telomere length and oxidative stress in offspring at birth and 12 years of age (12y). In a double-blind, placebo-controlled, parallel-group study, 98 pregnant atopic women were randomised to 4g/day of n-3 LCPUFA or control (olive oil [OO]), from 20 weeks gestation until delivery. Telomere length as a marker of cell senescence and plasma and urinary F2-isoprostanes as a marker of oxidative stress were measured in the offspring at birth and 12y. Maternal n-3 LCPUFA supplementation did not influence offspring telomere length at birth or at 12y with no changes over time. Telomere length was not associated with F2-isoprostanes or erythrocyte total n-3 fatty acids. Supplementation significantly reduced cord plasma F2-isoprostanes (P<0.001), with a difference in the change over time between groups (P=0.05). However, the differences were no longer apparent at 12y. Between-group differences for urinary F2-isoprostanes at birth and at 12y were non-significant with no changes over time. This study does not support the hypothesis that n-3 LCPUFA during pregnancy provides sustained effects on postnatal oxidative stress and telomere length as observed in the offspring. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Monetary Valuation of Lifetime Health Improvement and Life Expectancy Gains in Turkey

PubMed Central

Tekeşin, Cem

2017-01-01

The main objective of this study is to estimate the monetary value of the gains of healthy days and life expectancy due to the ambient air quality standard that came into effect in 2014 by estimating the country-specific value of a life year (VOLY) and the value of the healthier and longer life (VHLL) for Turkey. Contingent valuation method is adopted to reveal individuals’ willingness to pay for an improvement of health condition and the extension of their life expectancy by avoiding respiratory and lung related illnesses. VHLL is composed of two parts, WTP for an extension of one’s life years (VOLY) and for an increase in the number of healthy days throughout one’s life time (VHLL-VOLY). We found that close to 80% of WTP is allocated to the latter component of VHLL and only 20% is for VOLY mainly due to Islamic beliefs of the respondents. A total of 1314 observations are collected by face-to-face interviews from Afsin-Elbistan, Kutahya-Tavsanli and Ankara. The estimated VHLL and VOLY are [41,750 TL, 10,258 TL] with all the observations, [30,185 TL, 7132 TL] for Afsin-Elbistan, [31,718 TL, 7081 TL] for Kutahya-Tavsanli and [52,334 TL, 14,813 TL] for Ankara. The Inverse-U shaped relationship between Age and WTP is confirmed. The income elasticities of WTP is found to be close to 0.5 for all study areas while an Inverse-U shaped relationship between the household income and Income Elasticity of WTP is observed in the income group based analysis. Age and household income are the two prominent determinants of VHLL. PMID:28961227

The Monetary Valuation of Lifetime Health Improvement and Life Expectancy Gains in Turkey.

PubMed

Ara, Shihomi; Tekeşin, Cem

2017-09-29

The main objective of this study is to estimate the monetary value of the gains of healthy days and life expectancy due to the ambient air quality standard that came into effect in 2014 by estimating the country-specific value of a life year (VOLY) and the value of the healthier and longer life (VHLL) for Turkey. Contingent valuation method is adopted to reveal individuals' willingness to pay for an improvement of health condition and the extension of their life expectancy by avoiding respiratory and lung related illnesses. VHLL is composed of two parts, WTP for an extension of one's life years (VOLY) and for an increase in the number of healthy days throughout one's life time (VHLL-VOLY). We found that close to 80% of WTP is allocated to the latter component of VHLL and only 20% is for VOLY mainly due to Islamic beliefs of the respondents. A total of 1314 observations are collected by face-to-face interviews from Afsin-Elbistan, Kutahya-Tavsanli and Ankara. The estimated VHLL and VOLY are [41,750 TL, 10,258 TL] with all the observations, [30,185 TL, 7132 TL] for Afsin-Elbistan, [31,718 TL, 7081 TL] for Kutahya-Tavsanli and [52,334 TL, 14,813 TL] for Ankara. The Inverse-U shaped relationship between Age and WTP is confirmed. The income elasticities of WTP is found to be close to 0.5 for all study areas while an Inverse-U shaped relationship between the household income and Income Elasticity of WTP is observed in the income group based analysis. Age and household income are the two prominent determinants of VHLL.

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

Carvalho, P.A.; Garada, B.M.; Loeffler, J.S.

To verify the utility of a volumetric estimation of Tl-201 uptake in the context of possible astrocytoma recurrence after surgery, radiotherapy plus stereotactic boost (radiosurgery/brachitherapy), we analyzed sequential Tl-201/Tc99m-HMPAO brain SPECT studies of 28 patients (18 m/10 f). These were categorized as having tumor mass recurrence (TM), infiltrating tumor cells but no definite tumor mass (IT), or radiation changes and necrosis (RCN) after stereotactic biopsy and/or craniotomy. SPECT studies were obtained with a high-resolution dedicated gamma camera (CERASPECT, Digital Scinitgraphics, Inc.) and image acquisition was performed after intravenous Tl-201 (18.5 MBq) and Tc-99m HMPAO (740 MBq). In order to includemore » relevant information about tumor burden, a volumetric index of Tl-201 uptake was expressed in cm{sup 3} related to voxel size (4.6 x 10{sup -3} cc) within an elliptical ROI that included the tumor area. Only voxels with a threshold {ge} 2 in relation to the average scalp Tl-201 uptake were included and this total number of voxels expressed in cc was compared to previously established maximal tumor/scalp Tl-201 uptake ratios (T/S) and histopathology. Results are presented as the median (min-max) and differences were considered significant for p<0.05. Differences were significant between all groups for both ratios and volume indices and correlation between the two variables was 0.90. In conclusion, the volumetric index of Tl-201 is similar to the maximal Tl-201 T/S ratios in discriminating tumor recurrence and radiation necrosis, suggesting a future role for the volumetric index estimation in the evaluation of treatment efficacy and patient follow-up.« less

Reduced anti-ferromagnetism promoted by Zn 3d 10 substitution at CuO 2 planar sites of Cu 0.5Tl 0.5Ba 2Ca 3Cu 4O 12-δ superconductors

NASA Astrophysics Data System (ADS)

Mumtaz, M.; Khan, Nawazish A.

2009-11-01

The role of charge carriers in ZnO 2/CuO 2 planes of Cu 0.5Tl 0.5Ba 2Ca 3Cu 4-yZn yO 12-δ material in bringing about superconductivity has been explained. Due to suppression of anti-ferromagnetic order with Zn 3d 10 ( S=0) substitution at Cu 3d 9(S={1}/{2}) sites in the inner CuO 2 planes of Cu 0.5Tl 0.5Ba 2Ca 3Cu 4O 12-δ superconductor, the distribution of charge carriers becomes homogeneous and optimum, which is evident from the enhanced superconductivity parameters. The decreased c-axis length with the increase of Zn doping improves interlayer coupling and hence the three dimensional (3D) conductivity in the unit cell is enhanced. Also the softening of phonon modes with the increased Zn doping indicates that the electron-phonon interaction has an essential role in the mechanism of high- Tc superconductivity in these compounds.

Do mud deposition events on sandy beaches affect surf zone ichthyofauna? A southern Brazilian case study

NASA Astrophysics Data System (ADS)

Mont'Alverne, Renata; Moraes, Leonardo E.; Rodrigues, Fábio L.; Vieira, João P.

2012-05-01

Using fluid mud deposition events which occur regularly at Cassino Beach in south Brazil, we evaluated the influence of such events on the structure of the ichthyofauna inhabiting its shallow surf zone. Wave action was the dominant factor in differentiating between sampling sites, being lower or even absent at the mud-influenced sectors compared to beach area without mud. Samples were collected using a beach seine net at two control locations (A1 and A2), and at three locations influenced by mud deposition (B1, B2, and B3). During the study period (21 April-04 August 2009), 15,245 fishes were captured and separated into 26 taxonomic groups, from species to family. Individuals of a total length (TL) up to 50 mm accounted for 65% of the catch, while individuals of TL < 30 mm were the most numerous and more responsible for the total abundance spatial pattern. The area with higher wave action (A2) had the lowest relative species abundance and greatest diversity, whereas the areas with mud-forced lowest wave action (B2 and B3) had the highest species abundance values. Three hypotheses were proposed to explain the higher concentration and capture of juvenile fishes at mud locations. First, longshore currents may be responsible for the displacement of juvenile aggregations toward areas of lower energy. Second, individuals may select habitats with turbid waters, which may provide greater protection from predators and increased food availability. Third, areas under the influence of fluid mud deposition show higher values of viscosity, which may reduce swimming activity and hinder the escape of juvenile fishes from nets, resulting in an increased capture of individuals compared to areas without mud.

Implications of scaled δ15N fractionation for community predator-prey body mass ratio estimates in size-structured food webs.

PubMed

Reum, Jonathan C P; Jennings, Simon; Hunsicker, Mary E

2015-11-01

Nitrogen stable isotope ratios (δ(15) N) may be used to estimate community-level relationships between trophic level (TL) and body size in size-structured food webs and hence the mean predator to prey body mass ratio (PPMR). In turn, PPMR is used to estimate mean food chain length, trophic transfer efficiency and rates of change in abundance with body mass (usually reported as slopes of size spectra) and to calibrate and validate food web models. When estimating TL, researchers had assumed that fractionation of δ(15) N (Δδ(15) N) did not change with TL. However, a recent meta-analysis indicated that this assumption was not as well supported by data as the assumption that Δδ(15) N scales negatively with the δ(15) N of prey. We collated existing fish community δ(15) N-body size data for the Northeast Atlantic and tropical Western Arabian Sea with new data from the Northeast Pacific. These data were used to estimate TL-body mass relationships and PPMR under constant and scaled Δδ(15) N assumptions, and to assess how the scaled Δδ(15) N assumption affects our understanding of the structure of these food webs. Adoption of the scaled Δδ(15) N approach markedly reduces the previously reported differences in TL at body mass among fish communities from different regions. With scaled Δδ(15) N, TL-body mass relationships became more positive and PPMR fell. Results implied that realized prey size in these size-structured fish communities are less variable than previously assumed and food chains potentially longer. The adoption of generic PPMR estimates for calibration and validation of size-based fish community models is better supported than hitherto assumed, but predicted slopes of community size spectra are more sensitive to a given change or error in realized PPMR when PPMR is small. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

Thermoluminescence dating of Hawaiian basalt

USGS Publications Warehouse

May, Rodd James

1979-01-01

The thermoluminescence (TL) properties of plagioclase separates from 11 independently dated alkalic basalts 4,500 years to 3.3 million years old and 17 tholeiitic basalts 16 years to 450,000 years old from the Hawaiian Islands were investigated for the purpose of developing a TL dating method for young volcanic rocks. Ratios of natural to artificial TL intensity, when normalized for natural radiation dose rates, were used to quantify the thermoluminescence response of individual samples for age-determination purposes. The TL ratios for the alkalic basalt plagioclase were found to increase with age at a predictable exponential rate that permits the use of the equation for the best-fit line through a plot of the TL ratios relative to known age as a TL age equation. The equation is applicable to rocks ranging in composition from basaltic andesite to trachyte over the age range from about 2,000 to at least 250,000 years before present (B.P.). The TL ages for samples older than 50,000 years have a calculated precision of less than :t 10 percent and a potential estimated accuracy relative to potassium-argon ages of approximately :t 10 percent. An attempt to develop a similar dating curve for the tholeiitic basalts was not as successful, primarily because the dose rates are on the average lower than those for the alkalic basalts by a factor of 6, resulting in lower TL intensities in the tholeiitic basalts for samples of equivalent age, and also because the age distribution of dated material is inadequate. The basic TL properties of the plagioclase from the two rock types are similar, however, and TL dating of tholeiitic basalts should eventually be feasible over the age range 10,000 to at least 200,000 years B.P. The average composition of the plagioclase separates from the alkalic basalts ranges from oligoclase to andesine; compositional variations within this range have no apparent effect on the TL ratios. The average composition of the plagioclase from the tholeiitic basalts is labradorite. The natural radiogenic dose rates for the alkalic basalts calculated on the basis of assumed secular equilibrium range from 0.228 to 0.462 rad per year and average 0.335 rad per year exclusive of the cosmic-ray energy dose and with the alpha-particle component equal to one-tenth of the total alpha decay energy. The TL measurements were made using material of a 37 to 44-micrometer size range; the crushing required during sample preparation was found to have a negligible effect on natural TL. Both natural and artificial TL were filtered to the bandwidth 3,500 A to 5,000 A to restrict the light detected to that from the plagioclase emission peak centered at about 4,500 A and associated with structural defects. Within this bandwidth, the natural TL from both the alkalic and tholeiitic basalt plagioclase consists of a single peak with a maximum amplitude at about 350?C; the artificial TL glow curves produced by an exposure of the drained samples to a standard dose of X-radiation consist of four broad, variably overlapping peaks with maxima at about 110?C, 150?C, 225?C, and 300?C. The maximum amplitude of the 350?C natural and 300?C artificial TL peaks, both produced by the same general activation energy distribution of trapping centers, were used for TL dating. The high-temperature artificial TL peak occurs at a lower temperature than the corresponding natural TL peak owing to the presence of a large number of electrons retained in traps near the lower end of the trap-depth energy range in samples whose TL is measured a short time after intense artificial irradiation. These traps remain essentially empty in the natural environment owing to spontaneous decay and do not produce measurable low-temperature natural TL peaks. With prolonged storage after irradiation, the 300?C artificial TL peak migrates to higher temperatures and decreases in amplitude.

1D-TlInSe2: Band Structure, Dielectric Function and Nanorods

NASA Astrophysics Data System (ADS)

Mamedov, Nazim; Wakita, Kazuki; Akita, Seiji; Nakayama, Yoshikazu

2005-01-01

Linear combination of atomic orbitals (LCAO) analysis of the electronic band states has been completed for one-dimensional (1D) TlInSe2 having rod-like ground state shape of bulky crystal. The total scenario of the occurrence of the band states from the atomic states has been established. According to this scenario, in dipole approximation the optical transitions at band gap (point T of Brillouin zone) are either entirely forbidden or allowed for T2-T10 transitions in e\\perpc configuration provided that either initial or terminate state has T2 symmetry and both are Se-like. As a whole, the obtained results on the electronic spectrum, including dielectric function, are applicable to all obtained 1D-TlInSe2 nanorods which were as thin as 30--50 nm in cross-section, and apparently preserved tetragonal crystal structure of bulky material. The thermal instabilities developing already in bulky samples of 1D-TlInSe2 are considered to be an ultimate source of the nanoparticles emerging in plenty during nanorods preparation. The nanoplates of a chemically similar but 2D material, TlInS2, are demonstrated for comparison to show the absence of nanoparticles in that case. A possibility of nanoparticle preparation using laser excited coherent phonon trains in the nanorods of 1D-TlInSe2 is figured out.

Effects of atrial fibrillation on myocardial washout rate of thallium-201 on myocardial perfusion single-photon emission computed tomography.

PubMed

Kurisu, Satoshi; Nitta, Kazuhiro; Sumimoto, Yoji; Ikenaga, Hiroki; Ishibashi, Ken; Fukuda, Yukihiro; Kihara, Yasuki

2018-04-20

Myocardial perfusion single-photon emission computed tomography (SPECT) with thallium (Tl)-201 is an established modality for evaluating myocardial ischemia. We assessed the effects of atrial fibrillation (AF) on the myocardial washout rate (WR) of Tl-201 on myocardial perfusion SPECT. A total of 231 patients with no evidence of myocardial ischemia were enrolled retrospectively in this study. Patients were divided into two groups on the basis of the ECG at the time of myocardial perfusion SPECT. The mean myocardial WR of Tl-201 was calculated from the stress and the redistribution Bull's eye maps. There were 34 patients with AF and 197 patients with sinus rhythm. There were no significant differences in clinical variables, except for older age and higher heart rate in patients with AF. Myocardial WR of Tl-201 was significantly lower in patients with AF than those with sinus rhythm (46±12 vs. 51±8%, P=0.03). Multivariate analysis including these factors showed that female sex (β=0.18, P=0.02), AF (β=-0.14 P=0.03), hemoglobin (β=-0.18, P<0.01), and serum creatinine (β=0.24, P<0.01) were determinants of myocardial WR of Tl-201. Our data suggest that AF is associated with reduced myocardial WR of Tl-201 on myocardial perfuison SPECT.

THEORY AND MEASUREMENT OF VISUAL MECHANISMS

PubMed Central

Crozier, W. J.; Wolf, Ernst

1944-01-01

Flicker contours for a square image of 3° visual angle, centered 6° on the temporal side of the fovea, the light sectored at a focus, are strikingly modified if the same illuminated area is arranged in four squares separated by a narrow opaque cross. The "cone" curves are made much steeper, and their abscissae of inflection (τ' are at higher intensities; Fmax. is not greatly changed, but alters less with change of light-time fraction in the flash cycle (tL). This modification is accompanied by a great enlargement of the scotopic segment of the duplex curves, consistent with the theory of the integrative relations of neural effects in the two groups of units involved. The changes are not consistent with the view that flicker end-points are determined by the activation of retinal cells with a fixed spatial distribution of invariable thresholds. At tL = 0.50 the 3° subdivided area gives very nearly the same contour as does a square 6° x 6°, with the same total perimeter of light-dark separation; the "edge effect" thus suggested is complicated by differences in the dependence of Fmax. and τ' upon tL. When an image pattern is produced by a grid of light bars separated by equally broad opaque spaces (10° x 10° over-all, centered at the fovea), the photopic flicker contours are made very steep and their midpoints are situated at quite low intensities, while the "rod" contribution tends to be more completely fused with the "cone" than is found for fields not subdivided. However, instead of a progressive increase of τ' with tL the curves for tL = 0.75 and 0.90 lie respectively below that for tL = 0.25 and 0.50 for a field of four broader stripes (1.43°) and both are below tL = 0.25 for a field of seven narrower stripes (0.77°). These latter changes are discussed in terms of the participation of subsidiary phenomena involving so called "γ movement." It is pointed out that since in these data σ1/Im is for each set of conditions a statistically constant quantity with a characteristic breadth of scatter σσ, it is possible to calculate a "coefficient of internal correlation" r which is a function of the conditions (as: image area, location, wave length of light, structure of image, light-time fraction) and which describes a property of any entire contour. The changes in r, as a function of the conditions of flicker excitation, reflect changes in the neural organization responsible for the liminal discrimination of flicker. It is shown that as consequence of simple changes in the image field, three parameters, as of the probability summation, are required for the description of a simplex flicker contour—since each of these is independently modifiable as to its magnitude and in its dependence on the light-time fraction. Subdivision of the image, with light sectored at a focus, produces in part only the changes in the flicker contour which we have earlier labelled the "pecten effect." In the latter, with light not sectored at a focus but with bar images moving across a field with inclined fixed opaque bars, the "cone" slope (dF/d log I) is sharply increased for tL > 0.50, but not below tL = 0.50, and the value of τ' is much less than it "should be." Consequently, the change in contrast brought about by the moving contact of light/dark borders is the significant factor in the "pecten effect," not simply pulsatile interruption of the light. PMID:19873392

Positive Selection of γδ CTL by TL Antigen Expressed in the Thymus

PubMed Central

Tsujimura, Kunio; Takahashi, Toshitada; Morita, Akimichi; Hasegawa-Nishiwaki, Hitomi; Iwase, Shigeru; Obata, Yuichi

1996-01-01

To elucidate the function of the mouse TL antigen in the thymus, we have derived two TL transgenic mouse strains by introducing Tla a -3 of A strain origin with its own promoter onto a C3H background with no expression of TL in the thymus. These transgenic mouse strains, both of which express high levels of Tlaa-3-TL antigen in their thymus, were analyzed for their T cell function with emphasis on cytotoxic T lymphocyte (CTL) generation. A T cell response against TL was induced in Tg.Tlaa-3-1, Tg.Tlaa-3-2, and control C3H mice by skin grafts from H-2K b/T3 b transgenic mice, Tg.Con.3-1, expressing T3b-TL ubiquitously. Spleen cells from mice that had rejected the T3b-TL positive skin grafts were restimulated in vitro with Tg.Con.3-1 irradiated spleen cells. In mixed lymphocyte cultures (MLC), approximately 20% and 15% of Thy-1+ T cells derived from Tg.Tlaa-3-1 and Tg.Tlaa-3-2, respectively, expressed TCRγδ, whereas almost all those from C3H expressed TCRαβ. The MLC from Tg.Tlaa-3-2 and C3H demonstrated high CTL activity against TL, while those from Tg.Tlaa-3-1 had little or none. The generation of γδ CTL recognizing TL in Tg.Tlaa-3-2, but not C3H mice, was confirmed by the establishment of CTL clones. A total of 14 γδ CTL clones were established from Tg.Tlaa-3-2, whereas none were obtained from C3H. Of the 14 γδ CTL clones, 8 were CD8+ and 6 were CD4−CD8− double negative. The CTL activity of all these clones was TL specific and inhibited by anti-TL, but not by anti-H-2 antibodies, demonstrating that they recognize TL directly without antigen presentation by H-2. The CTL activity was blocked by antibodies to TCRγδ and CD3, and also by antibodies to CD8α and CD8β in CD8+ clones, showing that the activity was mediated by TCRγδ and coreceptors. The thymic origin of these γδ CTL clones was indicated by the expression of Thy-1 and Ly-1 (CD5), and also CD8αβ heterodimers in CD8+ clones on their surfaces and by the usage of TCR Vγ4 chains in 12 of the 14 clones. Taken together, these results suggest that Tlaa-3-TL antigen expressed in the thymus engages in positive selection of a sizable population of γδ T cells. PMID:8976173

Diet-related telomere shortening and chromosome stability

PubMed Central

Marcon, Francesca; Siniscalchi, Ester; Crebelli, Riccardo; Saieva, Calogero; Sera, Francesco; Fortini, Paola; Simonelli, Valeria; Palli, Domenico

2012-01-01

Recent evidences have highlighted an influence of micronutrients in the maintenance of telomere length (TL). In order to explore whether diet-related telomere shortening had any physiological relevance and was accompanied by significant damage in the genome, in the present study, TL was assessed by terminal restriction fragment (TRF) analysis in peripheral blood lymphocytes of 56 healthy subjects for which detailed information on dietary habits was available and data were compared \\with the incidence of nucleoplasmic bridges (NPBs), a marker of chromosomal instability related to telomere dysfunction visualised with the cytokinesis-blocked micronucleus assay. To increase the capability to detect even slight impairment of telomere function, the incidence of NPBs was also evaluated on cells exposed in vitro to ionising radiation. Care was taken to control for potential confounding factors that might influence TL, viz. age, hTERT genotype and smoking status. Data showed that higher consumption of vegetables was related with significantly higher mean TL (P = 0.013); in particular, the analysis of the association between micronutrients and mean TL highlighted a significant role of antioxidant intake, especially beta-carotene, on telomere maintenance (P = 0.004). However, the diet-related telomere shortening did not result in associated increased spontaneous or radiation-induced NPBs. The distribution of TRFs was also analysed and a slight prevalence of radiation-induced NPBs (P = 0.03) was observed in subjects with higher amount of very short TRFs (<2 kb). The relative incidence of very short TRFs was positively associate with ageing (P = 0.008) but unrelated to vegetables consumption and daily intake of micronutrients, suggesting that the degree of telomere erosion related with low dietary intake of antioxidants observed in this study was not so extensive to lead to chromosome instability. PMID:21857007

Measurement of intrinsic radioactive backgrounds from the 137Cs and U/Th chains in CsI(Tl) crystals

NASA Astrophysics Data System (ADS)

Liu, Shu-Kui; Yue, Qian; Lin, Shin-Ted; Li, Yuan-Jing; Tang, Chang-Jian; Wong Tsz-King, Henry; Xing, Hao-Yang; Yang, Chao-Wen; Zhao, Wei; Zhu, Jing-Jun

2015-04-01

The inorganic CsI(Tl) crystal scintillator is a candidate anti-compton detector for the China Dark matter Experiment. Studying the intrinsic radiopurity of the CsI(Tl) crystal is an issue of major importance. The timing, energy and spatial correlations, as well as the capability of pulse shape discrimination provide powerful methods for the measurement of intrinsic radiopurities. The experimental design, detector performance and event-selection algorithms are described. A total of 359×3 kg-days data from three prototypes of CsI(Tl) crystals were taken at China Jinping Underground Laboratory (CJPL), which offers a good shielding environment. The contamination levels of internal isotopes from 137Cs, 232Th and 238U series, as well as the upper bounds of 235U series are reported. Identification of the whole α peaks from U/Th decay chains and derivation of those corresponding quenching factors are achieved. Supported by National Natural Science Foundation of China (11275107, 11175099)

Patterns of metal composition and biological condition and their association in male common carp across an environmental contaminant gradient in Lake Mead National Recreation Area, Nevada and Arizona, USA

USGS Publications Warehouse

Patino, R.; Rosen, Michael R.; Orsak, E.L.; Goodbred, S.L.; May, T.W.; Alvarez, David; Echols, K.R.; Wieser, C.M.; Ruessler, S.; Torres, L.

2012-01-01

There is a contaminant gradient in Lake Mead National Recreation Area (LMNRA) that is partly driven by municipal and industrial runoff and wastewater inputs via Las Vegas Wash (LVW). Adult male common carp (Cyprinus carpio; 10 fish/site) were collected from LVW, Las Vegas Bay (receiving LVW flow), Overton Arm (OA, upstream reference), and Willow Beach (WB, downstream) in March 2008. Discriminant function analysis was used to describe differences in metal concentrations and biological condition of fish collected from the four study sites, and canonical correlation analysis was used to evaluate the association between metal and biological traits. Metal concentrations were determined in whole-body extracts. Of 63 metals screened, those initially used in the statistical analysis were Ag, As, Ba, Cd, Co, Fe, Hg, Pb, Se, Zn. Biological variables analyzed included total length (TL), Fulton's condition factor, gonadosomatic index (GSI), hematocrit (Hct), and plasma estradiol-17?? and 11-ketotestosterone (11kt) concentrations. Analysis of metal composition and biological condition both yielded strong discrimination of fish by site (respective canonical model, p< 0.0001). Compared to OA, pairwise Mahalanobis distances between group means were WB < LVB < LVW for metal concentrations and LVB < WB < LVW for biological traits. Respective primary drivers for these separations were Ag, As, Ba, Hg, Pb, Se and Zn; and TL, GSI, 11kt, and Hct. Canonical correlation analysis using the latter variable sets showed they are significantly associated (p<0.0003); with As, Ba, Hg, and Zn, and TL, 11kt, and Hct being the primary contributors to the association. In conclusion, male carp collected along a contaminant gradient in LMNRA have distinct, collection site-dependent metal and morpho-physiological profiles that are significantly associated with each other. These associations suggest that fish health and reproductive condition (as measured by the biological variables evaluated in this study) are influenced by levels of certain metals in the Lake Mead environment. ?? 2011.

High-dose ascorbic acid decreases cholesterolemic factors of an atherogenic diet in guinea pigs.

PubMed

Filis, Konstantinos; Anastassopoulou, Aikaterini; Sigala, Fragiska; Theodorou, Dimitrios; Manouras, Andreas; Leandros, Emanouel; Sigalas, Panagiotis; Hepp, Wolfgang; Bramis, John

2007-03-01

The study evaluates the effect of a high supplemental dose of ascorbic acid (AA) on plasma concentrations of total cholesterol (TC), triglycerides (TG), total lipids (TL), and lipoprotein fractions high-density, very-low-density-, and low-density lipoprotein (HDL, VLDL, LDL) in guinea pigs fed with atherogenic diet. Group I consisted of 5 normally fed guinea pigs plus a low dose of AA (1 mg/100 g/day), group II consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a low dose of AA (1 mg/100 g/day), and group III consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a high dose of AA (30 mg/100 g/day). Cholesterolemic factors concentrations were determined after nine weeks. Concentrations of TC, TG, TL, LDL, and VLDL were increased in group II compared to group I (p < 0.01 for all differences). Supplementation with a high dose of AA resulted in decreased concentrations of TC (p < 0.01), TG (p < 0.01), TL (p < 0.01), and LDL (p < 0.01) in group III compared to group II. Additionally, concentration of HDL was increased in group III compared to group II (p < 0.01). High-dose AA supplementation to an atherogenic diet decreases concentrations of TC, TG, TL, and LDL and increases concentration of HDL compared to low-dose AA.

Life after total laryngectomy: a measure of long-term survival, function, and quality of life.

PubMed

Woodard, Troy D; Oplatek, Agnes; Petruzzelli, Guy J

2007-06-01

To analyze postoperative clinical, functional, and quality-of-life (QOL) outcomes in patients after total laryngectomy (TL) and to determine the effect of preoperative variables (including age, sex, comorbidities, prior chemotherapy or radiation therapy, and tumor site and stage) on long-term survival and quality of life. We performed a retrospective cohort follow-up study of patients who underwent TL for cancer between July 28, 1994, and August 11, 2005. University tertiary care facility. One hundred forty-three patients who underwent TL were identified, and their hospital medical records were reviewed. Ninety-one patients (63.6%) underwent TL for primary carcinoma and 52 (36.4%) for recurrent cancer. At follow-up, 58 patients (40.6%) were alive. Baseline characteristics and preoperative clinical variables were collected. Follow-up data on function and QOL were collected from patients who were alive at the time of study via the Head and Neck Cancer Inventory, a previously validated questionnaire. Survival was estimated using the Kaplan-Meier method. Univariate and multivariate analysis was used to determine factors significant for survival. The overall median survival for the cohort was 23.0 months (mean +/- SD, 50 +/- 29 months). On univariate analysis, the following 5 factors were significant predictors of long-term survival: cancer site in the larynx, T3 stage, N0 to N1 stage, presence of no more than 2 comorbidities, and absence of cardiovascular comorbidities at the time of cancer diagnosis (P<.05). On multivariate analysis, only T stage maintained significance as a predictor of survival (P =.04), while cancer site was nonsignificant at P =.07. For patients alive at the time of study, functional and QOL outcomes for 5 domains (speech, eating, social disruption, aesthetics, and overall QOL) ranged from intermediate (score, 31-69) to high (score, 70-100) categories. Pretreatment patient-related factors that correlated with notably better functional and QOL outcomes in at least 1 domain were age older than 65 years at diagnosis, presence of no more than 2 comorbidities, no history of previous chemoradiation therapy, and primary tracheoesophageal puncture placement. Pretreatment clinical variables (including primary tumor site, tumor stage, regional metastases, and number and type of comorbidities) have an effect on long-term survival after TL. Despite common belief, many patients who have undergone TL maintain a good QOL overall. This study sheds light on which patient-related factors may affect health-related QOL outcomes after TL. These findings may be used to select patients who are good candidates for TL based on anticipated functional and QOL outcomes.

Energy density of bloaters in the upper Great Lakes

USGS Publications Warehouse

Pothoven, Steven A.; Bunnell, David B.; Madenjian, Charles P.; Gorman, Owen T.; Roseman, Edward F.

2012-01-01

We evaluated the energy density of bloaters Coregonus hoyi as a function of fish size across Lakes Michigan, Huron, and Superior in 2008–2009 and assessed how differences in energy density are related to factors such as biomass density of bloaters and availability of prey. Additional objectives were to compare energy density between sexes and to compare energy densities of bloaters in Lake Michigan between two time periods (1998–2001 and 2008–2009). For the cross-lake comparisons in 2008, energy density increased with fish total length (TL) only in Lake Michigan. Mean energy density adjusted for fish size was 8% higher in bloaters from Lake Superior than in bloaters from Lake Huron. Relative to fish in these two lakes, small (175 mm TL) bloaters had higher energy density. In 2009, energy density increased with bloater size, and mean energy density adjusted for fish size was about 9% higher in Lake Michigan than in Lake Huron (Lake Superior was not sampled during 2009). Energy density of bloaters in Lake Huron was generally the lowest among lakes, reflecting the relatively low densities of opossum shrimp Mysis diluviana and the relatively high biomass of bloaters reported for that lake. Other factors, such as energy content of prey, growing season, or ontogenetic differences in energy use strategies, may also influence cross-lake variation in energy density. Mean energy density adjusted for length was 7% higher for female bloaters than for male bloaters in Lakes Michigan and Huron. In Lake Superior, energy density did not differ between males and females. Finally, energy density of bloaters in Lake Michigan was similar between the periods 2008–2009 and 1998–2001, possibly due to a low population abundance of bloaters, which could offset food availability changes linked to the loss of prey such as the amphipods Diporeia spp.

The effect of flash-freezing temperature on stallion sperm DNA structure.

PubMed

Serafini, R; Varner, D D; Bissett, W; Blanchard, T L; Teague, S R; Love, C C

2017-06-01

The effect of flash-freezing storage temperature on stallion sperm DNA has not been evaluated. Commonly, sperm are flash-frozen at various temperatures to preserve sperm DNA prior to analysis. It is unclear whether the temperature at which sperm are frozen and stored may affect the results of DNA assays. In this study, the neutral comet assay was used to evaluate the effect of flash-freezing storage temperature (freezer [-60 °C], dry ice [-78.5 °C], liquid nitrogen [-196 °C]) compared to fresh sperm DNA structure. In addition, intra- and inter-assay and intra- and inter-stallion variabilities were determined. All comet tail measures were higher following any flash-freezing method, as compared to fresh sperm DNA (P < 0.05), with no difference among flash-frozen treatments (P > 0.05). For most comet variables, intra- and inter-assay variabilities were <10%. Intra- and inter-stallion variabilities revealed that comet head length (HL) and width (CW) were less variable as compared to comet tail values, i.e., % comet tail DNA (T-DNA), tail length (TL), tail moment (OTM), and tail migration (TM). Certain comet tail values in fresh (% T-DNA, and OTM) and flash-frozen sperm (OTM, % T-DNA, TL, and TM) were correlated to the Sperm Chromatin Structure Assay (SCSA) variable, COMP-α t . The comet tail measures were negatively correlated to % morphologically normal sperm (P < 0.05) and positively correlated to % abnormal heads and premature germ cells (P < 0.05). Variables COMP-α t and % total sperm motility were not correlated to any morphologic sperm feature in this group of stallions (P > 0.05). While significant differences in the structure of the sperm DNA were identified in the flash-frozen as compared to the fresh sperm DNA with the neutral comet assay, it cannot be assumed that these changes are fertility limiting. Copyright © 2017. Published by Elsevier Inc.

First-principles study of the heavy metal atoms X (X=Au, Hg, Tl or Pb) doped monolayer WS2

NASA Astrophysics Data System (ADS)

Xie, Ling-Yun; Zhang, Jian-Min

2017-12-01

The heavy metal atoms X (X = Au, Hg, Tl or Pb) doped monolayer WS2 systems have been studied by using the spin-polarized first-principles calculations. Although pure monolayer WS2 system is a nonmagnetic semiconductor with a direct band gap of 1.820 eV, the Au and Hg atoms doped monolayer WS2 systems change to half-metal (HM) ferromagnets with the total magnetic moments 0.697 and 1.776 μB as well as the smaller spin-down gaps 0.605 and 0.527 eV, respectively, while the Tl and Pb atoms doped monolayer WS2 systems change to magnetic metal with the total magnetic moment 0.584 μB and a nonmagnetic metal. From the minimization of the formation energy, we find that it is easy to incorporate these heavy metal atoms into monolayer WS2 system under S-rich condition, especially for the Au doped monolayer WS2 system not only easily to be formed but also a HM ferromagnet, and thus the best candidate used in the spintronic devices.

Comparison of organotin accumulation on the white-spotted charr Salvelinus leucomaenis between sea-run and freshwater-resident types

NASA Astrophysics Data System (ADS)

Ohji, Madoka; Harino, Hiroya; Arai, Takaomi

2011-01-01

To examine the accumulation pattern of organotin compounds (OTs) in relation to the migration of diadromous fish, tributyltin (TBT) and triphenyltin (TPT) compounds and their derivatives were determined in the muscle tissue of both sea-run (anadromous) and freshwater-resident (nonanadromous) types of the white-spotted charr Salvelinus leucomaenis. There were generally no significant correlations between the TBT and TPT accumulation and various biological characteristics such as the total length (TL), body weight (BW), age and sex in S. leucomaenis. It is noteworthy that the TBT and TPT concentrations in sea-run white-spotted charr were significantly higher than in freshwater-resident individuals, although they are intraspecies. These results suggest that the sea-run S. leucomaenis has a higher ecological risk of TBT and TPT exposure than the freshwater-residents during their life history.

78 FR 15672 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery Off the...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-12

... projected commercial and/or recreational fishing seasons are determined by NMFS to be 3 days or [[Page 15674... length (TL), minimum size limit for both the commercial and recreational sectors to decrease regulatory... Fisheries Service. [FR Doc. 2013-05644 Filed 3-11-13; 8:45 am] BILLING CODE 3510-22-P ...

Accelerated Time-Domain Modeling of Electromagnetic Pulse Excitation of Finite-Length Dissipative Conductors over a Ground Plane via Function Fitting and Recursive Convolution

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

Campione, Salvatore; Warne, Larry K.; Sainath, Kamalesh

In this report we overview the fundamental concepts for a pair of techniques which together greatly hasten computational predictions of electromagnetic pulse (EMP) excitation of finite-length dissipative conductors over a ground plane. In a time- domain, transmission line (TL) model implementation, predictions are computationally bottlenecked time-wise, either for late-time predictions (about 100ns-10000ns range) or predictions concerning EMP excitation of long TLs (order of kilometers or more ). This is because the method requires a temporal convolution to account for the losses in the ground. Addressing this to facilitate practical simulation of EMP excitation of TLs, we first apply a techniquemore » to extract an (approximate) complex exponential function basis-fit to the ground/Earth's impedance function, followed by incorporating this into a recursion-based convolution acceleration technique. Because the recursion-based method only requires the evaluation of the most recent voltage history data (versus the entire history in a "brute-force" convolution evaluation), we achieve necessary time speed- ups across a variety of TL/Earth geometry/material scenarios. Intentionally Left Blank« less

68Ga-PSMA-11 PET/CT-derived metabolic parameters for determination of whole-body tumor burden and treatment response in prostate cancer.

PubMed

Schmidkonz, Christian; Cordes, Michael; Schmidt, Daniela; Bäuerle, Tobias; Goetz, Theresa Ida; Beck, Michael; Prante, Olaf; Cavallaro, Alexander; Uder, Michael; Wullich, Bernd; Goebell, Peter; Kuwert, Torsten; Ritt, Philipp

2018-05-03

We aimed at evaluating the role of 68 Ga-PSMA-11 PET/CT-derived metabolic parameters for assessment of whole-body tumor burden and its capability to determine therapeutic response in patients with prostate cancer. A total of 142 patients with biochemical recurrence of prostate cancer underwent PET/CT with [ 68 Ga]Ga-PSMA-HBED-CC ( 68 Ga-PSMA-11). Quantitative assessment of all 641 68 Ga-PSMA-11-positive lesions in the field of view was performed to calculate PSMA-derived parameters, including whole-body PSMA tumor volume (PSMA-TV) and whole-body total lesion PSMA (TL-PSMA), as well as the established SUVmax and SUVmean values. All PET-derived parameters were tested for correlation with serum PSA levels and for association with Gleason scores. In 23 patients who underwent 68 Ga-PSMA-11 PET/CT before and after therapy with either external beam radiation, androgen deprivation, or docetaxel chemotherapy, SUVmax and TL-PSMA were compared to radiographic response assessment of CT images based on RECIST 1.1 criteria and to biochemical response determined by changes of serum PSA levels. PSMA-TV and TL-PSMA demonstrated a significant correlation with serum PSA levels (P < 0.0001) and TL-PSMA was significantly different for different Gleason scores. The agreement rate between TL-PSMA derived from PET and biochemical response was 87% (95% confidence interval, 0.66-0.97; Cohen's κ = 0.78; P < 0.01) and, thus, higher than for SUVmax, which was 74% (95% CI, 0.52-0.90; κ = 0.55; P < 0.01). Furthermore, agreement with PSA was higher for TL-PSMA and SUVmax than for CT-based response evaluation. Discordant findings between PET and CT were most likely due to limitations of CT and RECIST in rating small lymph nodes as metastases, as well as bone involvement, which was sometimes not detectable in CT. 68 Ga-PSMA-11 PET/CT-derived metabolic tumor parameters showed promising results for evaluation of treatment response. Especially, TL-PSMA demonstrated higher agreement rates with biochemical response compared to SUVmax. Larger, ideally prospective trials are needed to help to reveal the full potential of metabolic parameters derived from PET imaging with 68 Ga-PSMA-11.

Polymorphisms in the Myostatin-1 gene and their association with growth traits in Ancherythroculter nigrocauda

NASA Astrophysics Data System (ADS)

Sun, Yanhong; Li, Qing; Wang, Guiying; Zhu, Dongmei; Chen, Jian; Li, Pei; Tong, Jingou

2017-05-01

Myostatin ( MSTN) is a member of the transforming growth factor-β gene superfamily that negatively regulates skeletal muscle development and growth. In the present study, partial genomic fragments of Myostatin-1 ( MSTN-1) in two commercial hatchery populations of Ancherythroculter nigrocauda, an economically important freshwater fish, were screened for single nucleotide polymorphisms (SNPs) and then genotyped by direct sequencing of PCR products. Five SNPs were identified in intron 1 and exon 2, including a non-synonymous mutation causing an amino acid change (Val to Ile) at position 180. Association analyses based on 300 individuals revealed that the g.1129T>C SNP locus was significantly associated with total length (TL), body length (BL), body height (BH) and body weight (BW) in 6- and 18-month-old populations, while the g.1289G>A locus was significantly associated with BH and BW in the 6-month-old population. Haplotype analyses revealed that fish with the genotype combinations TC/TC or TC/GA showed better growth performance. Our results suggest that g.1129T>C and g.1289G>A have positive effects on growth traits and may be candidate gene markers for marker-assisted selection in A. nigrocauda.

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.

Tl{sub 2}Ba{sub 2}CuO{sub 6+{delta}} As a Model System for Fundamental Studies of High Temperature Superconductivity

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

Ren, Z.F.; Wang, J.H.

2000-05-22

During the past year, the Principal Investigator (PI) (Z. F. Ren) moved from SUNY-Buffalo to Boston College as an Associate Professor in the Department of Physics to further enhance the future success of this program. Due to the moving and set up of the new laboratory at Boston College, the project was slowed down in some extent. Nevertheless, the PI and his associates have been able to accomplish the following: (1) The upper critical field study has been carried out on the early samples (made when the PI was still with SUNY-Buffalo). Those samples have either high {Tc} (>20K) withmore » single transition or low TC but with double transitions. Therefore, there has no definitive conclusion been drawn yet. (2) X-ray photoemission has been used to study the Tl-2201 thin films. (3) In addition, J. Y. Lao has synthesized the epitaxial thallium-containing 1212 films with critical current density up to 10{sup 6}/cm{sup 2} at 77K and zero magnetic field as part of his Ph.D thesis. The success of this research has enabled us to consider using this material as an alternative for Yba{sub 2}Cu{sub 3}O{sub 7} (YBCO) or TlBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 9} (Tl-1223) for long length wire development for applications such as transmission cables, motors, generators, etc.« less

Telomeres and endocrine dysfunction of the adrenal and GH/IGF-1 axes.

PubMed

Aulinas, Anna; Ramírez, María José; Barahona, María José; Mato, Eugènia; Bell, Olga; Surrallés, Jordi; Webb, Susan M

2013-12-01

Telomeres, located at the end of linear chromosomes, are essential to maintain genomic stability. Telomere biology has recently emerged as an important player in the fields of ageing and disease. To maintain telomere length (TL) and reduce its degradation after mitosis, the telomerase enzyme complex is produced. Genetic, epigenetic, hormonal and environmental factors can regulate telomerase function. These include stress hormones such as cortisol and growth factors. The hypothalamic-pituitary-adrenal (HPA) axis has been evaluated in psychiatric diseases where hypercortisolism and oxidative stress are often present. Some researches have linked TL shortening to increases in stress-related cortisol, but others have not. The effects of cortisol on the telomere system are complex and may depend on the intensity and duration of exposure. On the other hand, low levels of IGF-1 are associated with inflammation and ageing-related diseases (ischaemic heart disease, congestive heart failure). Both IGF-1 and TL diminish with age and are positively and strongly correlated with each other. It is not clear whether this positive correlation reflects a single association or a cause-effect relationship. Further research will ideally investigate longitudinal changes in telomeres and both these hormonal axes. To our knowledge, TL dysfunction has not been described in either endogenous hypercortisolism (Cushing's syndrome) or acromegaly where excessive amounts of GH and consequently IGF-1 are produced. This review focuses on the possible relationships between telomere dysfunction and the hypothalamic-pituitary-adrenal (HPA) axis and GH-IGF-1 system. © 2013 John Wiley & Sons Ltd.

Insight meditation and telomere biology: The effects of intensive retreat and the moderating role of personality.

PubMed

Conklin, Quinn A; King, Brandon G; Zanesco, Anthony P; Lin, Jue; Hamidi, Anahita B; Pokorny, Jennifer J; Álvarez-López, María Jesús; Cosín-Tomás, Marta; Huang, Colin; Kaliman, Perla; Epel, Elissa S; Saron, Clifford D

2018-05-01

A growing body of evidence suggests that meditation training may have a range of salubrious effects, including improved telomere regulation. Telomeres and the enzyme telomerase interact with a variety of molecular components to regulate cell-cycle signaling cascades, and are implicated in pathways linking psychological stress to disease. We investigated the effects of intensive meditation practice on these biomarkers by measuring changes in telomere length (TL), telomerase activity (TA), and telomere-related gene (TRG) expression during a 1-month residential Insight meditation retreat. Multilevel analyses revealed an apparent TL increase in the retreat group, compared to a group of experienced meditators, similarly comprised in age and gender, who were not on retreat. Moreover, personality traits predicted changes in TL, such that retreat participants highest in neuroticism and lowest in agreeableness demonstrated the greatest increases in TL. Changes observed in TRGs further suggest retreat-related improvements in telomere maintenance, including increases in Gar1 and HnRNPA1, which encode proteins that bind telomerase RNA and telomeric DNA. Although no group-level changes were observed in TA, retreat participants' TA levels at post-assessment were inversely related to several indices of retreat engagement and prior meditation experience. Neuroticism also predicted variation in TA across retreat. These findings suggest that meditation training in a retreat setting may have positive effects on telomere regulation, which are moderated by individual differences in personality and meditation experience. (ClinicalTrials.gov #NCT03056105). Copyright © 2018. Published by Elsevier Inc.

Sex differences in leg dexterity are not present in elite athletes.

PubMed

Lawrence, Emily L; Peppoloni, Lorenzo; Valero-Cuevas, Francisco J

2017-10-03

We studied whether the time-varying forces that control unstable foot-ground interactions provide insight into the neural control of dynamic leg function. Twenty elite (10F, 26.4±3.5yrs) and 20 recreational (10F, 24.8±2.4yrs) athletes used an isolated leg to maximally compress a slender spring designed to buckle at low forces while seated. The foot forces during the compression at the edge of instability quantify the maximal sensorimotor ability to control dynamic foot-ground interactions. Using the nonlinear analysis technique of attractor reconstruction, we characterized the spatial (interquartile range IQR) and geometric (trajectory length TL, volume V, and sum of edge lengths SE) features of the dynamical behavior of those force time series. ANOVA confirmed the already published effect of sex, and a new effect of athletic ability, respectively, in TL (p=0.014 and p<0.001), IQR (p=0.008 and p<0.001), V (p=0.034 and p=0.002), and SE (p=0.033 and p<0.001). Further analysis revealed that, for recreational athletes, females exhibited weaker corrective actions and greater stochasticity than males as per their greater mean values of TL (p=0.003), IQR (p=0.018), V (p=0.017), and SE (p=0.025). Importantly, sex differences disappeared in elite athletes. These results provide an empirical link between sex, athletic ability, and nonlinear dynamical control. This is a first step in understanding the sensorimotor mechanisms for control of unstable foot-ground interactions. Given that females suffer a greater incidence of non-contact knee ligament injuries, these non-invasive and practical metrics of leg dexterity may be both indicators of athletic ability, and predictors of risk of injury. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of water temperature and fish size on predation vulnerability of juvenile humpback chub to rainbow trout and brown trout

USGS Publications Warehouse

Ward, David L.; Morton-Starner, Rylan

2015-01-01

Predation on juvenile native fish by introduced Rainbow Trout and Brown Trout is considered a significant threat to the persistence of endangered Humpback Chub Gila cypha in the Colorado River in the Grand Canyon. Diet studies of Rainbow Trout and Brown Trout in Glen and Grand canyons indicate that these species do eat native fish, but impacts are difficult to assess because predation vulnerability is highly variable, depending on prey size, predator size, and the water temperatures under which the predation interactions take place. We conducted laboratory experiments to evaluate how short-term predation vulnerability of juvenile native fish changes in response to fish size and water temperature using captivity-reared Humpback Chub, Bonytail, and Roundtail Chub. Juvenile chub 45–90 mm total length (TL) were exposed to adult Rainbow and Brown trouts at 10, 15, and 20°C to measure predation vulnerability as a function of water temperature and fish size. A 1°C increase in water temperature decreased short-term predation vulnerability of Humpback Chub to Rainbow Trout by about 5%, although the relationship is not linear. Brown Trout were highly piscivorous in the laboratory at any size > 220 mm TL and at all water temperatures we tested. Understanding the effects of predation by trout on endangered Humpback Chub is critical in evaluating management options aimed at preserving native fishes in Grand Canyon National Park.

Skin parasitism by Paratrichosoma recurvum in wild American crocodiles and its relation to environmental and biological factors.

PubMed

Charruau, Pierre; Pérez-Flores, Jonathan S; Labarre, Didier

2017-01-24

Paratrichosma spp. are capillarid worms that parasitize the abdominal skin of crocodiles. They are likely not a threat to crocodiles' health, but they affect the skins' commercial value. No successful treatment exists against this parasite, and present knowledge of its life cycle is limited. Herein we report new information on Paratrichosoma recurvum occurrence in wild American crocodiles Crocodylus acutus from Mexican Caribbean islands and its relation to environmental (water salinity, temperature, climatic events) and biological (body condition) factors. The percentage of parasitized crocodiles (30.3%) is among the highest recorded in wild crocodilian populations. Small (<40.8 cm total length [TL]) and large (>270 cm TL) crocodiles are less parasitized, probably due to the characteristics of their skin or of the parasite life cycle. Two individuals appeared to have eliminated worms naturally between their capture and recapture. The thorax-abdomen is the most parasitized area of the body of crocodiles. The risk of infection is not associated with the sex of the crocodile, but there was a difference in the proportion of parasitized crocodiles between sites, which could be related to different environmental conditions. The body condition of a crocodile does not seem to be affected by the parasite. Climatic events and water temperature show no effect on the parasitism of crocodiles, but salinity could have an effect. The infection of crocodiles by P. recurvum could depend more on an individual's behavior than on environmental conditions.

Trophic ecology of yellownose skate Zearaja chilensis, a top predator in the south-western Atlantic Ocean.

PubMed

Belleggia, M; Andrada, N; Paglieri, S; Cortés, F; Massa, A M; Figueroa, D E; Bremec, C

2016-03-01

The diet and trophic level (TL ) of the yellownose skate Zearaja chilensis in the south-western Atlantic Ocean (35°-54° S), and how these varied in relation to body size, sex, maturity stage, depth and region were determined by analysis of stomach contents. From 776 specimens analysed, 671 (86·5%) ranging from 180 to 1190 mm total length (LT ) had prey in their stomachs. The diet was dominated by fishes, mainly the notothenioid Patagonotothen ramsayi and the Argentine hake Merluccius hubbsi. The consumption of fishes and crabs increased with increasing predator size, and these preys were more important in the north than in the south. Isopods and other crustaceans were consumed more in the south and their consumption decreased as the size of Z. chilensis increased. The TL of Z. chilensis increased with LT from 4·29 to 4·59 (mean 4·53), confirming their ecological role as a top predator. The small and large size classes exhibited a low diet overlap and the highest spatial segregation, whereas medium and large specimens had higher co-occurrence and dietary overlap indices. A clear distinction in tooth shape was noted between sexes in adult specimens, with males having longer cusps. This sexual heterodonty may be related to reproductive behaviour, increasing the grasping ability of males during courtship, because there were no differences in diet between the sexes. © 2016 The Fisheries Society of the British Isles.

Secondary interactions in thallium(I) coordination, [Tl 2(DBM) 2] n, DBM - = 1,3-diphenylpropane-1,3-dionate (dibenzoylmethanide)

NASA Astrophysics Data System (ADS)

Askarinejad, Azadeh; Morsali, Ali; Zhu, Long-Guan

2006-05-01

The Tl I complex of 1,3-diphenylpropane-1,3-dionate (dibenzoylmethanide, DBM -), [Tl 2(DBM) 2] n, has been synthesized and characterized. The single-crystal X-ray data show there are two different Tl environments. One type of Tl-atom in the TlO 4C 6Tl 2 environment is twelve-coordinated, with two weak Tl⋯Tl and hexahapto ( η) interactions, TlC 6. The other type of Tl-atom in the TlO 4C 2Tl 2 units is eight-coordinated, with two weak Tl⋯Tl and dihapto ( η) interactions, TlC 2. The dimeric units [Tl 2(DBM) 2] linked through Tl⋯Tl and polyhapto interactions, TlC 6 and TlC 2, and produce the 1D polymeric chains. Comparison with the analogous Pb(II) compound indicates that Tl I may also act as both a Lewis acid and a Lewis base.

Prior Tubal Ligation Might Influence Metastatic Spread of Nonendometrioid Endometrial Carcinoma.

PubMed

Li, Mingxia; Li, Mingzhu; Zhao, Lijun; Wang, Zhiqi; Wang, Yue; Shen, Danhua; Wang, Jianliu; Wei, Lihui

2016-07-01

The exfoliation of endometrial carcinoma might intraperitoneally spread through the fallopian tube. We analyzed the influence of prior tubal ligation (TL) in endometrial carcinoma to evaluate whether it can prevent the process and improve patients' survival. A total of 562 patients with a diagnosis of endometrial carcinoma at the Peking University People's Hospital between July 1995 and June 2012 were enrolled in this study. The patients were divided into 2 groups based on the presence or absence of prior TL. International Federation of Gynecology and Obstetrics stage distributions, recurrence rates, survival status, and histopathological findings were compared between the 2 groups. Kaplan-Meier estimates and log-rank tests were used to compare the survival status based on TL in the overall population and stratified by histopathological subtypes and International Federation of Gynecology and Obstetrics stages. Cox models analysis was used to estimate the hazard ratios and 95% confidence intervals for associations between TL and carcinoma-specific mortality. All statistical tests were 2-sided. Of the 562 patients, 482 (85.7%) had a diagnosis of endometrioid and 80 patients (14.2%) with nonendometrioid carcinoma. Tubal ligation was associated with negative peritoneal cytology in the total population (P = 0.015) and in patients with endometrioid carcinomas (P = 0.02) but not help to reduce carcinoma-specific mortality (P = 0.095 and P = 0.277, respectively). In the nonendometrioid group, TL was not only associated with negative peritoneal cytology (P = 0.004) but also with lower stage (P < 0.001) and lower recurrence rate(P < 0.005), resulting in improved prognosis (P = 0.022). In Cox models analysis adjusted for covariates, TL was inversely associated with lower endometrial carcinoma-specific mortality (hazard ratio, 0.47; 95% confidence interval, 0.14-2.6). Tubal ligation was associated with lower positive peritoneal cytology, stages, and recurrence rate, and improved prognosis among patients with nonendometrioid carcinoma. Tubal ligation might influence metastatic spread of nonendometrioid endometrial carcinoma. It could also help to reduce positive peritoneal cytology among patients with endometrioid carcinoma, but lacked prognostic significance.

Systematics and faunistics of Neotropical Eucosmini. 1. Chimoptesis Powell, 1964 (Lepidoptera: Tortricidae).

PubMed

Razowski, Ózef; Becker, Vitor Osmar

2015-03-31

Twenty-one new species of Chimoptesis are described and illustrated: C. costaricae (TL: Costa Rica: San José), C. phanera (TL: Mexico: Chiapas), C. rubigo (TL: Mexico: Chiapas), C. rosariana (TL: Cuba: Pinar Rio), C. miniaula (TL: Mexico: Chiapas), C. kallion (TL: Mexico: Chiapas), C. potosiana (TL: Mexico: Nuevo Leon), C. obliquaria (TL: Mexico: Nuevo Leon), C. angulata (TL: Mexico: Chiapas), C. dentitia (TL: Mexico: Chiapas), C. faceta (TL: Mexico: Nuevo Leon), C. caera (TL: Mexico: Chiapas), C. castanescens (TL: Mexico: Chiapas), C. albomixta (TL: Mexico: Distrito Federal), C. cornigera (TL: Mexico: Nuevo Leon), C. mitrion (TL: Mexico: Nuevo Leon), C. setoses (TL: Cuba: Santiago), C. juniptesis (TL: Mexico: Chiapas), C. tamaulipasia (TL: Mexico: Tamaulipas), C. zoquiapana (Mexico: Distrito Federal), and C. rufobrunnea (TL: Costa Rica: San José). Formerly known only from the U.S., Chimoptesis is recorded south to Costa Rica in Central America and Cuba in the Caribbean.

Emergence, Development, and Maturity of the Gonad of Two Species of Chitons “Sea Cockroach” (Mollusca: Polyplacophora) through the Early Life Stages

PubMed Central

Avila-Poveda, Omar Hernando; Abadia-Chanona, Quetzalli Yasú

2013-01-01

This study describes and recognises, using histological and microscopical examinations on a morphometrical basis, several gonad traits through the early life stages of Chiton articulatus and C. albolineatus. Gonadal ontogenesis, gonad development stages, sexual differentiation, onset of the first sexual maturity, and growth sequences or “early life stages” were determined. In addition, allometry between lengths and body weight pooled for both sexes per each chiton were calculated using equation Y = aXb. A total of 125 chitons (4≤TL≤40 mm, in total length “TL”) were used. All allometric relations showed a strong positive correlation (r), close to 1, with b-values above three, indicating an isometric growth. Gonadal ontogenesis and gonad development stages were categorised into three periods (“Pw” without gonad, “Pe” gonad emergence, and “Pf” gonadal sac formed) and four stages (“S0” gametocytogenesis, “S1” gametogenesis, “S2” mature, and “S3” spawning), respectively. Compound digital images were attained for each process. Periods and stages are overlapped among them and between species, with the following overall confidence intervals in TL: Pw 6.13–14.32 mm, Pe 10.32–16.93 mm, Pf 12.99–25.01 mm, S0 16.08–24.34 mm (females) and 19.51–26.60 mm (males), S1 27.15–35.63 mm (females) and 23.45–32.27 mm (males), S2 24.48–40.24 mm (females) and 25.45–32.87 mm (males). Sexual differentiation (in S0) of both chitons occurs first as a female then as a male; although, males reach the onset of the first sexual maturity earlier than females, thus for C. articulatus males at 17 mm and females at 32 mm, and for C. albolineatus males at 23.5 mm and females at 28 mm, all in TL. Four early life stages (i.e., subjuvenile, juvenile, subadult, and adult) are described and proposed to distinguish growth sequences. Our results may be useful to diverse disciplines, from developmental biology to fisheries management. PMID:23936353

Windowpane flounder (Scophthalmus aquosus) and winter flounder (Pseudopleuronectes americanus) responses to cold temperature extremes in a Northwest Atlantic estuary

NASA Astrophysics Data System (ADS)

Wilber, Dara H.; Clarke, Douglas G.; Alcoba, Catherine M.; Gallo, Jenine

2016-01-01

The effect of climate variability on flatfish includes not only the effects of warming on sensitive life history stages, but also impacts from more frequent or unseasonal extreme cold temperatures. Cold weather events can affect the overwintering capabilities of flatfish near their low temperature range limits. We examined the responses of two flatfish species, the thin-bodied windowpane (Scophthalmus aquosus) and cold-tolerant winter flounder (Pseudopleuronectes americanus), to variable winter temperatures in a Northwest Atlantic estuary using abundance and size data collected during a monitoring study, the Aquatic Biological Survey, conducted from 2002 to 2010. Winter and spring abundances of small (50 to 120 mm total length) juvenile windowpane were positively correlated with adult densities (spawning stock) and fall temperatures (thermal conditions experienced during post-settlement development for the fall-spawned cohort) of the previous year. Windowpane abundances in the estuary were significantly reduced and the smallest size class was nearly absent after several consecutive years with cold (minimum temperatures < 1 °C) winters. Interannual variation in winter flounder abundances was unrelated to the severity of winter temperatures. A Paulik diagram illustrates strong positive correlations between annual abundances of sequential winter flounder life history stages (egg, larval, Age-1 juvenile, and adult male) within the estuary, reflecting residency within the estuary through their first year of life. Temperature variables representing conditions during winter flounder larval and post-settlement development were not significant factors in multiple regression models exploring factors that affect juvenile abundances. Likewise, densities of predators known to consume winter flounder eggs and/or post-settlement juveniles were not significantly related to interannual variation in winter flounder juvenile abundances. Colder estuarine temperatures through the first year of life were associated with smaller Age-1 winter flounder body size. For example, Age-1 winter flounder developing under conditions that differed by 1.9 °C in mean daily water temperature, averaged 98.7 mm total length (TL) and 123.1 mm TL, for the relatively cold vs. moderate years, respectively. More frequent cold temperature extremes associated with climate variability may negatively impact the overwintering capabilities of some flatfish near their cold temperature range limits, whereas cold-tolerant species may experience reduced growth, which imparts the ecological challenges associated with smaller body size.

Enhancement of lanthanide evaporation by complexation: dysprosium tri-iodide mixed with indium iodide and thulium tri-iodide mixed with thallium iodide.

PubMed

Curry, J J; Estupiñán, E G; Henins, A; Lapatovich, W P; Shastri, S D; Hardis, J E

2013-09-28

The vapors in equilibrium with condensates of DyI3, DyI3/InI, TmI3, and TmI3/TlI were observed over the temperature range from 900 K to 1400 K using x-ray induced fluorescence. The total densities of each element (Dy, Tm, In, Tl, and I) in the vapor, summed over all atomic and molecular species, were determined. Dramatic enhancements in the total vapor densities of Dy and Tm were observed in the vapors over DyI3/InI and TmI3/TlI as compared to the vapors over pure DyI3 and pure TmI3, respectively. An enhancement factor exceeding 10 was observed for Dy at T ≈ 1020 K, decreasing to 0 at T ≈ 1250 K. An enhancement factor exceeding 20 was observed for Tm at T ≈ 1040 K, decreasing to 0 at T ≈ 1300 K. Such enhancements are expected from the formation of the vapor-phase hetero-complexes DyInI4 and TmTlI4. Numerical simulations of the thermo-chemical equilibrium suggest the importance of additional complexes in liquid phases. A description of the measurement technique is given. Improvements in the absolute calibration lead to an approximately 40% correction to previously reported preliminary results [J. J. Curry et al., Chem. Phys. Lett. 507, 52 (2011); Appl. Phys. Lett. 100, 083505 (2012)].

SABRE: Dark matter annual modulation detection in the northern and southern hemispheres

NASA Astrophysics Data System (ADS)

Tomei, C.

2017-02-01

SABRE (Sodium-iodide with Active Background REjection) is a new NaI(Tl) experiment designed to search for galactic Dark Matter through the annual modulation signature. SABRE will consist of highly pure NaI(Tl) crystals operated in an active liquid scintillator veto. The SABRE experiment will follow a two-phase approach. In the first phase, one high-purity NaI(Tl) crystal will be operated at LNGS in an active liquid scintillator veto with the goal of demonstrating backgrounds low enough for a sensitive test of the DAMA/LIBRA result. An unprecedented radio-purity for both the NaI powder and the crystal growth will be needed to achieve this goal. The second phase will consist in building two high-purity NaI(Tl) detector arrays, with a total mass of about 50 kg each, located at LNGS and in the Stawell Gold Mine in Australia. The operation of twin full-scale experiments in both the northern and the southern hemispheres will strengthen the reliability of the result against any possible seasonal systematic effect.

Synthesis and reactivity of dimeric Ar'TlTlAr' and trimeric (Ar"T1)3 (Ar', Ar" = bulky terphenyl group) thallium(I) derivatives: Tl(I)-Tl(I) bonding in species ligated by monodentate ligands.

PubMed

Wright, Robert J; Phillips, Andrew D; Hino, Shirley; Power, Philip P

2005-04-06

The synthesis and characterization of three new organothallium(I) compounds are reported. Reaction of (Ar'Li)(2) (Ar' = C(6)H(3)-2,6-(C(6)H(3)-2,6-Pr(i)(2))(2)) and Ar"Li (Ar" = C(6)H(3)-2,6-(C(6)H(3)-2,6-Me(2))(2)) with TlCl in Et(2)O afforded (Ar'Tl)(2) (1) and (Ar' 'Tl)(3) (2). The "dithallene" 1 is the heaviest group 13 dimetallene and features a planar, trans-bent structure with Ar'Tl-Tl = 119.74(14) degrees and Tl-Tl = 3.0936(8) A. Compound 2 is the first structurally characterized neutral, three-membered ring species of formula c-(MR)(3) (M = Al-Tl; R = organo group). The Tl(3) ring has Tl-Tl distances in the range ca. 3.21-3.37 A as well as pyramidal Tl geometries. The Tl-Tl bonds in 1 and 2 are outside the range (2.88-2.97 A) of Tl-Tl single bonds in R(2)TlTlR(2) compounds. The weak Tl-Tl bonding in 1 and 2 leads to their dissociation into Ar'Tl and Ar' 'Tl monomers in hexane. The Ar'Tl monomer behaves as a Lewis base and readily forms a 1:1 donor-acceptor complex with B(C(6)F(5))(3) to give Ar'TlB(C(6)F(5))(3), 3. Adduct 3 features an almost linear thallium C(ipso)-Tl-B angle of 174.358(7) degrees and a Tl-B distance of 2.311(2) A, which indicates strong association. Treatment of 1 with a variety of reagents resulted in no reactions. The lower reactivity of 1 is in accord with the reluctance of Tl(I) to undergo oxidation to Tl(III) due to the unreactive character of the 6s(2) electrons.

Thermo and mechanoluminescence of Dy3+ activated K2Mg2(SO4)3 phosphor

NASA Astrophysics Data System (ADS)

Panigrahi, A. K.; Dhoble, S. J.; Kher, R. S.; Moharil, S. V.

2003-08-01

A solid state diffusion method for the preparation of (K2 : Dy)Mg2(SO4)3 and (K2 : Dy,P)Mg2(SO4)3 phosphors is reported. Thermoluminescence (TL) and mechanoluminescence (ML) characteristics are studied. TL, shown by the (K2 : Dy,P)Mg2(SO4)3 phosphor is 60% as intense as the conventional CaSO4 : Dy phosphor used in the TLD of ionization radiation. It has a linear TL dose response and a negligible fading. These properties of (K2 : Dy,P)Mg2(SO4)3 should be suitable in dosimetry of ionization radiation using TL technique. ML of (K2 : Dy)Mg2(SO4)3 shows one peak which has been observed in ML intensity versus time curve. The ML peak shows the recombination of electrons with free radicals (anion radicals produced by γ-irradiation) released from traps during the mechanical pressure applied on the Dy activated K2Mg2(SO4)3 phosphor. This ML mechanism is proposed for γ-irradiated sulfate based phosphors. It has been found that the total light output, i.e. ML intensity, increases with concentration of dopant, strain rate and irradiation dose of the phosphor. Mechanoluminescence and ML emission spectra of (K2 : Dy)Mg2(SO4)3 were recorded for better understanding of the ML process. The TL and ML measurements have also been performed to elucidate the mechanism of ML. Some correlation between ML and TL has also been found.

Academic satisfaction among traditional and problem based learning medical students. A comparative study.

PubMed

Albarrak, Ahmed I; Mohammed, Rafiuddin; Abalhassan, Mohammed F; Almutairi, Nasser K

2013-11-01

To evaluate the academic satisfaction and importance among traditional learning (TL) and problem based learning (PBL) medical students, and to further evaluate the areas of concern in the academic education from the student's point of view. A cross sectional study was conducted at the College of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia from May to June 2012. The survey questionnaires were self-administered and consisted of mainly 6 sections: teaching, learning, supervision, course organization, information technology (IT) facilities, and development of skills. A total of 92 TL (males: 66 [71.7%]; females: 26 [28.3%]), and 108 PBL (males: 84 [77.8%]; females: 24 [22.1%]), with a mean age of 21.3 +/- 1.3 (TL), and 20.7 +/- 1.0 (PBL) were included in the study. The overall satisfaction rate was higher in the PBL students when compared with TL students in: teaching (84.7%/60.3%); learning (81.4%/64.5%); supervision (80%/51.5%); course organization (69.3%/46.9%); IT facilities (74.0%/58.9%); and development of skills (79.1%/53.9%). There was statistical significance difference in academic satisfaction comparing both groups of students (p

Age and growth of round gobies in Lake Michigan, with preliminary mortality estimation

USGS Publications Warehouse

Huo, Bin; Madenjian, Charles P.; Xie, Cong X.; Zhao, Yingming; O'Brien, Timothy P.; Czesny, Sergiusz J.

2015-01-01

The round goby (Neogobius melanostomus) is a prevalent invasive species throughout Lake Michigan, as well as other Laurentian Great Lakes, yet little information is available on spatial variation in round goby growth within one body of water. Age and growth of round goby at three areas of Lake Michigan were studied by otolith analysis from a sample of 659 specimens collected from 2008 to 2012. Total length (TL) ranged from 48 to 131 mm for Sturgeon Bay, from 50 to 125 mm for Waukegan, and from 54 to 129 mm for Sleeping Bear Dunes. Ages ranged from 2 to 7 years for Sturgeon Bay, from 2 to 5 years for Waukegan, and from 2 to 6 years for Sleeping Bear Dunes. Area-specific and sex-specific body–otolith relationships were used to back-calculate estimates of total length at age, which were fitted to von Bertalanffy models to estimate growth rates. For both sexes, round gobies at Sleeping Bear Dunes and Waukegan grew significantly faster than those at Sturgeon Bay. However, round goby growth did not significantly differ between Sleeping Bear Dunes and Waukegan for either sex. At all three areas of Lake Michigan, males grew significantly faster than females. Based on catch curve analysis, estimates of annual mortality rates ranged from 0.79 to 0.84. These relatively high mortality rates suggested that round gobies may be under predatory control in Lake Michigan.

Effects of a 2-Week High-Intensity Training Camp on Sleep Activity of Professional Rugby League Athletes.

PubMed

Thornton, Heidi R; Duthie, Grant M; Pitchford, Nathan W; Delaney, Jace A; Benton, Dean T; Dascombe, Ben J

2017-08-01

To investigate the effects of a training camp on the sleep characteristics of professional rugby league players compared with a home period. During a 7-d home and 13-d camp period, time in bed (TIB), total sleep time (TST), sleep efficiency (SE), and wake after sleep onset were measured using wristwatch actigraphy. Subjective wellness and training loads (TL) were also collected. Differences in sleep and TL between the 2 periods and the effect of daytime naps on nighttime sleep were examined using linear mixed models. Pearson correlations assessed the relationship of changes in TL on individuals' TST. During the training camp, TST (-85 min), TIB (-53 min), and SE (-8%) were reduced compared with home. Those who undertook daytime naps showed increased TIB (+33 min), TST (+30 min), and SE (+0.9%). Increases in daily total distance and training duration above individual baseline means during the training camp shared moderate (r = -.31) and trivial (r = -.04) negative relationships with TST. Sleep quality and quantity may be compromised during training camps; however, daytime naps may be beneficial for athletes due to their known benefits, without being detrimental to nighttime sleep.

Integrating the internal and external training loads in soccer.

PubMed

Akubat, Ibrahim; Barrett, Steve; Abt, Grant

2014-05-01

This study aimed to assess the relationships of fitness in soccer players with a novel integration of internal and external training load (TL). Ten amateur soccer players performed a lactate threshold (LT) test followed by a soccer simulation (Ball-Sport Endurance and Sprint Test [BEAST90mod]). The results from the LT test were used to determine velocity at lactate threshold (vLT), velocity at onset of blood lactate accumulation (vOBLA), maximal oxygen uptake (VO2max), and the heart rate-blood lactate profile for calculation of internal TL (individualized training impulse, or iTRIMP). The total distance (TD) and high intensity distance (HID) covered during the BEAST90mod were measured using GPS technology that allowed measurement of performance and external TL. The internal TL was divided by the external TL to form TD:iTRIMP and HID:iTRIMP ratios. Correlation analyses assessed the relationships between fitness measures and the ratios to performance in the BEAST90mod. vLT, vOBLA, and VO2max showed no significant relationship to TD or HID. HID:iTRIMP significantly correlated with vOBLA (r = .65, P = .04; large), and TD:iTRIMP showed a significant correlation with vLT (r = .69, P = .03; large). The results suggest that the integrated use of ratios may help in the assessment of fitness, as performance alone showed no significant relationships with fitness.

Hybrid procedure for total laryngectomy with a flexible robot-assisted surgical system.

PubMed

Schuler, Patrick J; Hoffmann, Thomas K; Veit, Johannes A; Rotter, Nicole; Friedrich, Daniel T; Greve, Jens; Scheithauer, Marc O

2017-06-01

Total laryngectomy is a standard procedure in head-and-neck surgery for the treatment of cancer patients. Recent clinical experiences have indicated a clinical benefit for patients undergoing transoral robot-assisted total laryngectomy (TORS-TL) with commercially available systems. Here, a new hybrid procedure for total laryngectomy is presented. TORS-TL was performed in human cadavers (n = 3) using a transoral-transcervical hybrid procedure. The transoral approach was performed with a robotic flexible robot-assisted surgical system (Flex®) and compatible flexible instruments. Transoral access and visualization of anatomical landmarks were studied in detail. Total laryngectomy is feasible with a combined transoral-transcervical approach using the flexible robot-assisted surgical system. Transoral visualization of all anatomical structures is sufficient. The flexible design of the robot is advantageous for transoral surgery of the laryngeal structures. Transoral robot assisted surgery has the potential to reduce morbidity, hospital time and fistula rates in a selected group of patients. Initial clinical studies and further development of supplemental tools are in progress. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Fishery biology and management of Protonibea diacanthus (Sciaenidae) aggregations in far Northern Cape York Peninsula waters

NASA Astrophysics Data System (ADS)

Phelan, M. J.; Gribble, N. A.; Garrett, R. N.

2008-09-01

The sciaenid Protonibea diacanthus is a large, long-lived predatory fish of inshore northern Australian waters, which forms annual aggregations that are fished extensively by traditional (subsistence) and recreational fishers. There are now widespread concerns that the resource is being overexploited. Indigenous fishers of the Cape York Northern Peninsula Area (NPA) relate that large adult fish (up to 1500 mm total length (TL)) made up the bulk of the catch from the sciaenid aggregations until about 1994. In contrast, sexually mature P. diacanthus comprised only a small component (12 fish out of 270=4.4%) examined in a 1999-2000 sampling programme that was biased towards the largest individuals available. At 790 mm TL, the minimum size at first maturity for female P. diacanthus in this study is much smaller than the 920 mm TL reported previously in Queensland waters. Developing ovaries were observed in specimens sampled from sciaenid aggregations which formed in NPA waters between May and September 2000. However, no fish with ripe or spent gonads were found in the study, so the current timing and location of the spawning season for P. diacanthus in the region remain unknown. Food items observed in the analysis of the diet of P. diacanthus from the NPA included a variety of teleosts and invertebrates. The range of animal taxa represented in the prey items support the description of an 'opportunistic predator' attributed to the species. In our sampling, the stomach contents of fish caught during the time of the aggregation events did not differ from those observed at other times of the year. A total of 114 P. diacanthus were tagged and released at aggregation sites during the study period, and 3 fish (2.6%) were subsequently recaptured. The low rate of tag returns from the wild stock tagging programme, both in this study (2.6%) and from recreational fisher tag/release programmes for the sciaenid elsewhere in Queensland (6.5%), were not explained by tag loss nor mortality, given the high retention rate of tags and the zero mortality seen in tank trials. In response to the biological findings from this study, indigenous community councils of the NPA imposed a 2-year fishing moratorium for P. diacanthus. Surveys at aggregation sites in 2002 and 2003 established that much larger fish (mean size 103.5 cm TL) were again present on the grounds, albeit in very low numbers. These recent preliminary results highlight the critical need for continued monitoring and management of the P. diacanthus fishery in the NPA, if prospects for resource recovery are to be realised. The NPA initiative has provided a rare opportunity to negotiate a co-management strategy, based on scientific data and traditional knowledge, for the recovery of a cultural and economically significant fished resource.

A TALE-inspired computational screen for proteins that contain approximate tandem repeats.

PubMed

Perycz, Malgorzata; Krwawicz, Joanna; Bochtler, Matthias

2017-01-01

TAL (transcription activator-like) effectors (TALEs) are bacterial proteins that are secreted from bacteria to plant cells to act as transcriptional activators. TALEs and related proteins (RipTALs, BurrH, MOrTL1 and MOrTL2) contain approximate tandem repeats that differ in conserved positions that define specificity. Using PERL, we screened ~47 million protein sequences for TALE-like architecture characterized by approximate tandem repeats (between 30 and 43 amino acids in length) and sequence variability in conserved positions, without requiring sequence similarity to TALEs. Candidate proteins were scored according to their propensity for nuclear localization, secondary structure, repeat sequence complexity, as well as covariation and predicted structural proximity of variable residues. Biological context was tentatively inferred from co-occurrence of other domains and interactome predictions. Approximate repeats with TALE-like features that merit experimental characterization were found in a protein of chestnut blight fungus, a eukaryotic plant pathogen.

A TALE-inspired computational screen for proteins that contain approximate tandem repeats

PubMed Central

Krwawicz, Joanna

2017-01-01

TAL (transcription activator-like) effectors (TALEs) are bacterial proteins that are secreted from bacteria to plant cells to act as transcriptional activators. TALEs and related proteins (RipTALs, BurrH, MOrTL1 and MOrTL2) contain approximate tandem repeats that differ in conserved positions that define specificity. Using PERL, we screened ~47 million protein sequences for TALE-like architecture characterized by approximate tandem repeats (between 30 and 43 amino acids in length) and sequence variability in conserved positions, without requiring sequence similarity to TALEs. Candidate proteins were scored according to their propensity for nuclear localization, secondary structure, repeat sequence complexity, as well as covariation and predicted structural proximity of variable residues. Biological context was tentatively inferred from co-occurrence of other domains and interactome predictions. Approximate repeats with TALE-like features that merit experimental characterization were found in a protein of chestnut blight fungus, a eukaryotic plant pathogen. PMID:28617832

Relationships Between Internal and External Training Load in Team-Sport Athletes: Evidence for an Individualized Approach.

PubMed

Bartlett, Jonathan D; O'Connor, Fergus; Pitchford, Nathan; Torres-Ronda, Lorena; Robertson, Samuel J

2017-02-01

The aim of this study was to quantify and predict relationships between rating of perceived exertion (RPE) and GPS training-load (TL) variables in professional Australian football (AF) players using group and individualized modeling approaches. TL data (GPS and RPE) for 41 professional AF players were obtained over a period of 27 wk. A total of 2711 training observations were analyzed with a total of 66 ± 13 sessions/player (range 39-89). Separate generalized estimating equations (GEEs) and artificial-neural-network analyses (ANNs) were conducted to determine the ability to predict RPE from TL variables (ie, session distance, high-speed running [HSR], HSR %, m/min) on a group and individual basis. Prediction error for the individualized ANN (root-mean-square error [RMSE] 1.24 ± 0.41) was lower than the group ANN (RMSE 1.42 ± 0.44), individualized GEE (RMSE 1.58 ± 0.41), and group GEE (RMSE 1.85 ± 0.49). Both the GEE and ANN models determined session distance as the most important predictor of RPE. Furthermore, importance plots generated from the ANN revealed session distance as most predictive of RPE in 36 of the 41 players, whereas HSR was predictive of RPE in just 3 players and m/min was predictive of RPE in just 2 players. This study demonstrates that machine learning approaches may outperform more traditional methodologies with respect to predicting athlete responses to TL. These approaches enable further individualization of load monitoring, leading to more accurate training prescription and evaluation.

Monosodium glutamate versus diet induced obesity in pregnant rats and their offspring.

PubMed

Afifi, M M; Abbas, Amr M

2011-06-01

We aim at determining the role of monosodium glutamate (MSG) compared with high caloric chow(HCC) in development of obesity in pregnant rats and their offspring. Ninety pregnant rats were divided into 3 groups, control, MSG and HCC fed. We determined energy intake, body weight (BW), abdominal fat, fat to body weight ratio, serum glucose, insulin, leptin, lipid profile, ob and leptin receptor-b gene expressions in pregnant rats and ob and leptin receptor-b gene expressions, serum insulin,glucose, leptin, triacylglycerides (TAG), total lipids (TL) and BW in offspring. Although daily energy intake and BW of MSG treated rats were lower than those of HCC fed rats, their abdominal fat and fat body weight ratio were higher. MSG or HCC increased Ob gene expression, leptin, insulin,LDL, cholesterol, total lipids (TL), glucose and decreased leptin receptor-b gene expression. In offspring of MSG treated rats, BW, serum glucose, insulin, leptin, TAG, TL and Ob gene expression increased and leptin receptor-b gene expression decreased whereas in offspring of HCC fed rats, serum insulin, leptin, Ob and leptin receptor-b gene expression increased but serum glucose, TAG, TL or BW did not change. We conclude that in pregnant rats, MSG, in spite of mild hypophagia, caused severe increase in fat body weight ratio, via leptin resistance, whereas, HCC increased BW and fat body weight ratio, due to hyperphagia with consequent leptin resistance. Moreover, maternal obesity in pregnancy, caused by MSG, has greater impact on offspring metabolism and BW than that induced by HCC.

The Integration of Internal and External Training Load Metrics in Hurling

PubMed Central

Doran, Dominic; Akubat, Ibrahim; Collins, Kieran

2016-01-01

Abstract The current study aimed to assess the relationship between the hurling player’s fitness profile and integrated training load (TL) metrics. Twenty-five hurling players performed treadmill testing for VO2max, the speed at blood lactate concentrations of 2 mmol•L-1 (vLT) and 4 mmol•L-1 (vOBLA) and the heart rate-blood lactate profile for calculation of individual training impulse (iTRIMP). The total distance (TD; m), high speed distance (HSD; m) and sprint distance (SD; m) covered were measured using GPS technology (4-Hz, VX Sport, Lower Hutt, New Zealand) which allowed for the measurement of the external TL. The external TL was divided by the internal TL to form integration ratios. Pearson correlation analyses allowed for the assessment of the relationships between fitness measures and the ratios to performance during simulated match play. External measures of the TL alone showed limited correlations with fitness measures. Integrated TL ratios showed significant relationships with fitness measures in players. TD:iTRIMP was correlated with aerobic fitness measures VO2max (r = 0.524; p = 0.006; 95% CI: 0.224 to 0.754; large) and vOBLA (r = 0.559; p = 0.003; 95% CI: 0.254 to 0.854; large). HSD:iTRIMP also correlated with aerobic markers for fitness vLT (r = 0.502; p = 0.009; 95% CI: 0.204 to 0.801; large); vOBLA (r = 0.407; p = 0.039; 95% CI: 0.024 to 0.644; moderate). Interestingly SD:iTRIMP also showed significant correlations with vLT (r = 0.611; p = 0.001; 95% CI: 0.324 to 0.754; large). The current study showed that TL ratios can provide practitioners with a measure of fitness as external performance alone showed limited relationships with aerobic fitness measures. PMID:28149425

Parasites of the deep-sea fish Mora moro (Risso, 1810) from the NW Mediterranean Sea and relationship with fish diet and enzymatic biomarkers

NASA Astrophysics Data System (ADS)

Dallarés, Sara; Constenla, María; Padrós, Francesc; Cartes, Joan E.; Solé, Montse; Carrassón, Maite

2014-10-01

Specimens of Mora moro were collected in two seasons and three localities of the Balearic Sea (NW Mediterranean Sea) and parasitological, dietary (to prey-species level), enzymatic and histological data were obtained, alongside with environmental information (T, S, O2). The relationships among fish parasite load, condition indices, diet, enzymatic activity of muscular acetylcholinesterase (AChE) and lactate dehydrogenase (LDH), intensity of splenic melano-macrophage centres (MMC) and hepatic granulomas were tested. M. moro showed a rich and abundant parasite fauna, and was a new host record for 17 out of the 18 different endoparasite taxa found. Significant differences were detected among locality-season groups, in turn related to different environmental variables, for Anisakidae gen. sp., Anisakis Type II and Tetraphyllidea fam. gen. sp.; thus, they are proposed as potentially useful as biological tags for geographical discrimination of M. moro in the NW Mediterranean Sea. Detailed relationships were found between parasite taxa and prey ingested (e.g. Anisakidae gen. sp. related with meso-bathypelagic crustaceans; Anisakis Type I with benthopelagic squids). Most parasites were linked to samples with highest levels of near-bottom O2, which is consistent with direct relationships found between near-bottom O2 and zooplankton biomass in the Balearic Basin. Total parasite abundance and the abundance of Tetraphyllidea fam. gen. sp. showed a significant relationship with the activity of AChE and the abundance of Anisakis Type II with LDH. AChE was associated with hepatosomatic index (HSI) and condition factor (K); LDH with gonadosomatic index (GSI), K and fish total length (TL). LDH activity showed differences among sampling groups. Splenic MMC and hepatic granulomas were not associated with fish parasite load. A positive relationship was found between MMC area and fish TL and LDH activity.

Toxicity of agricultural subsurface drainwater from the San Joaquin Valley, California to juvenile chinook salmon and striped bass

USGS Publications Warehouse

Saiki, Michael K.; Jennings, Mark R.; Wiedmeyer, Raymond H.

1992-01-01

Juvenile chinook salmon Oncorhynchus tshawytscha (40-50 mm total length, TL) and striped bass Morone saxatilis (30-40 mm TL) were exposed to serial dilutions (100, 50, 25, and 12.5%) of agricultural subsurface drainwater (WWD), reconstituted drainwater (RWWD), and reconstituted seawater (IO). Agricultural subsurface drainwater contained naturally elevated concentrations of major ions (such as sodium and sulfate) and trace elements (especially boron and selenium), RWWD contained concentrations of major ions that mimicked those in WWD but trace elements were not elevated, and IO contained concentrations of total dissolved salt that were similar to those in WWD and RWWD but chloride replaced sulfate as the dominant anion. After 28 d of static exposure, over 75% of the chinook salmon in 100% WWD had died, whereas none had died in other dilutions and water types. Growth of chinook salmon in WWD and RWWD, but not in IO, exhibited dilution responses. All striped bass died in 100% WWD within 23 d, whereas 19 of 20 striped bass had died in 100% RWWD after 28 d. In contrast, none died in 100% IO. Growth of striped bass was impaired only in WWD. Fish in WWD accumulated as much as 200 μg/g (dry-weight basis) of boron, whereas fish in control water accumulated less than 3.1 μg/g. Although potentially toxic concentrations of selenium occurred in WWD (geometric means, 158-218 μg/L), chinook salmon and striped bass exposed to this water type accumulated 5.7 μg Se/g or less. These findings indicate that WWD was toxic to chinook salmon and striped bass. Judging from available data, the toxicity of WWD was due primarily to high concentrations of major ions present in atypical ratios, to high concentrations of sulfate, or to both. High concentrations of boron and selenium also may have contributed to the toxicity of WWD, but their effects were not clearly delineated.

Diet and feeding behaviour of longnosed skate Dipturus oxyrinchus.

PubMed

Mulas, A; Bellodi, A; Cannas, R; Cau, Al; Cuccu, D; Marongiu, M F; Porcu, C; Follesa, M C

2015-01-01

A total of 255 longnosed skate Dipturus oxyrinchus caught in Sardinian waters (central-western Mediterranean Sea), was analysed with respect to fish total length (LT ), season and depth, in order to provide information on diet and feeding behaviour. Specimens ranging from 93 to 1153 mm LT , were collected at depths between 121 and 671 m, during experimental trawl surveys carried out from 2005 to 2010. The diet comprised crustaceans [prey specific index of relative importance (%IPSRI ) = 72·69], teleosts (%IPSRI  = 10·28) and molluscs (%IPSRI  = 10·94). Levins' index (Bi ) showed a narrow niche breadth (Bi  = 0·35). The mean ± s.e. trophic level (TL ) was 3·63 ± 0·50. The analysis showed major ontogenetic changes in the feeding behaviour. Early life stages were characterized by a benthic diet, which changed to benthopelagic during growth. Mysids, particularly Lophogaster typicus (%IPSRI  = 34·51), were the main prey items of immature individuals, replaced by euphausiids, mainly Meganyctiphanes norvegica (%IPSRI  = 13·19), in maturing fish. Crustaceans became less important in mature specimens, being replaced by molluscs (%IPSRI  = 28·99) and teleosts (%IPSRI  = 24·56). A concomitant increase of the TL was recorded (mean ± s.e. = 3·41 ± 0·44, 3·75 ± 0·54 and 4·28 ± 0·61 for immature, maturing and mature individuals). These feeding patterns ensured low levels of intraspecific competition. This study provides new information about the role that the D. oxyrinchus plays in the marine food chain and data now essential to formulate new and effective management plans for this species. © 2014 The Fisheries Society of the British Isles.

Effectiveness of integrated teaching module in pharmacology among medical undergraduates.

PubMed

Yadav, Preeti P; Chaudhary, Mayur; Patel, Jayshree; Shah, Aashal; Kantharia, N D

2016-01-01

Over the years with advancement of science and technology, each subject has become highly specialized. Teaching of medical students has still remained separate in various departments with no scope of integration in majority of medical institutes in India. Study was planned to have an experience of integration in institute and sensitize faculty for integrated teaching-learning (TL) method. To prepare and test effectiveness of integrated teaching module for 2(nd) year MBBS student in pharmacology and to sensitize and motivate faculties toward advantages of implementing integrated module. Education intervention project implemented 2(nd) year MBBS students of Government Medical College and New Civil Hospital, Surat. Students of second MBBS were divided into two groups. One group was exposed to integrated teaching sessions and another to traditional method. Both the groups were assessed by pre- and post-test questionnaire, feedback and focus group discussions were conducted to know their experience about process. A total of 165 students of the 2(nd) year MBBS were exposed to the integrated teaching module for two topics in two groups. One group was taught by traditional teaching, and another group was exposed to the integrated TL session. Both the groups have shown a significant improvement in posttest scores but increase in mean score was more in integrated group. During analysis of feedback forms, it was noted that students preferred integrated TL methods since they help in better understanding. Faculty feedback shows consensus over the adaptation of integrated TL methods. Integrated TL sessions were well-appreciated by students and faculties. To improve the critical reasoning skills and self-directed learning of students, integrated TL is highly recommended for must know areas of curriculum.

The Thermoluminescent Response of Several Phosphors to Monoenergetic Photon Beams with Energies from 275 TO 2,550 EV.

NASA Astrophysics Data System (ADS)

Carrillo Beltran, Ricardo Enrique

The thermoluminescent (TL) response of LiF:Mg,Ti (TLD-100) and CaF_2:Dy (TLD-200) to monoenergetic photon beams was measured for photons with energies between 275 and 2,550 eV produced by the Aladdin synchrotron accelerator of the UW-Madison. The change of the TL response, as measured by the 130-215 ^circC integrated light output for TLD-100, the 170-250^circC TL interval for TLD-200 and the height of the main dosimetric peak at 200^circC for both phosphors as a function of total energy deposited up to saturation is described. Glow curves were determined for TLDs annealed in helium and irradiated at various photon energies. Glow curves showing the adverse effect of air annealing upon the TL sensitivity of these phosphors are presented as well. Supralinearity factors for each TLD type were calculated using the integrated TL and the main peak height and are listed for the photon energy beams employed. High surface doses were achieved with these irradiations because of the short mean free path of the photons and the even shorter range of the freed electrons, both plotted. Despite the shallower penetration of the photons in TLD-200 as compared to TLD-100, the former phosphor was found to be more suitable for routine use as a synchrotron radiation monitor because its TL properties change very little with photon energy as shown by its constant glow curve obtained. TLD-100 glow curve, either from a chip or a crystal, changed according to the photon energy employed; this adverse effect was more pronounced with the chips.

The relationship of training load to physical-capacity changes during international tours in high-performance junior tennis players.

PubMed

Murphy, Alistair P; Duffield, Rob; Kellett, Aaron; Reid, Machar

2015-03-01

Given the travel that punctuates junior tennis development, an understanding of the changes in fitness owing to touring and the association between training loads (TLs) and fitness on return is vital. The authors investigated physical-capacity changes from pretour to posttour, determining if those changes were related to the TL of athletes on tour. Thirty junior athletes completed fitness testing before and after 4-wk tours. Testing included double-leg countermovement jump (CMJ), dominant single-leg and nondominant single-leg CMJ, speed (5, 10, 20 m), modified 5-0-5 agility (left and right), 10 × 20-m repeated-sprint ability (RSA), and multistage fitness tests. Repeated-measures ANOVAs determined physical-capacity change, with effect-size analysis establishing the magnitude of change. To avoid regression toward the mean, a 1/3-split technique was implemented for comparative analysis (high to low TLs). Moderate effects (d=0.50-0.70) for reductions of up to 3.6% in 5-, 10-, and 20-m speeds were observed. However, all remaining changes were only of trivial to small magnitude (d<0.40). Closer analysis of the interaction between TL and physical capacities (1/3-split) revealed that subjects who completed the greatest amount of total and tennis TL returned with a greater decline in speed and aerobic capacities (d>0.80). Furthermore, it was observed that match load dictates on- and off-court TL, with an increase in matches won understandably stunting exposure to off-court TL. Specific training should be prescribed on tour to maintain speed characteristics over a 4-wk international tour. On-tour training schedules should be carefully monitored to maximize specific TL exposure after losses on tour.

The influence of radiation-induced defects on thermoluminescence and optically stimulated luminescence of α-Al2O3:C

NASA Astrophysics Data System (ADS)

Nyirenda, A. N.; Chithambo, M. L.

2017-04-01

It is known that when α-Al2O3:C is exposed to excessive amounts of ionising radiation, defects are induced within its matrix. We report the influence of radiation-induced defects on the thermoluminescence (TL) and optically stimulated luminescence (OSL) measured from α-Al2O3:C after irradiation to 1000 Gy. These radiation-induced defects are thermally unstable in the region 450-650 °C and result in TL peaks in this range when the TL is measured at 1 °C/s. Heating a sample to 700 °C obliterates the radiation-induced defects, that is, the TL peaks corresponding to the radiation induced defects are no longer observed in the subsequent TL measurements when moderate irradiation doses below 10 Gy are used. The charge traps associated with these radiation-induced defects are more stable than the dosimetric trap when the sample is exposed to either sunlight or 470-nm blue light from LEDs. TL glow curves measured following the defect-inducing irradiation produce a dosimetric peak that is broader and positioned at a higher temperature than observed in glow curves obtained before the heavy irradiation. In addition, sample sensitization/desensitization occurs due to the presence of these radiation-induced defects. Furthermore, both the activation energy and the kinetic order of the dosimetric peak evaluated when the radiation-induced defects are present in the sample are significantly lower in value than those obtained when these defects are absent. The radiation-induced defects also affect the shape and total light sum of the OSL signal as well as the position and width of the resultant residual phototransferred thermoluminescence main peak.

Reference Equations for Static Lung Volumes and TLCO from a Population Sample in Northern Greece.

PubMed

Michailopoulos, Pavlos; Kontakiotis, Theodoros; Spyratos, Dionisios; Argyropoulou-Pataka, Paraskevi; Sichletidis, Lazaros

2015-02-14

Background: The most commonly used reference equations for the measurement of static lung volumes/capacities and transfer factor of the lung for CO (TL CO ) are based on studies around 30-40 years old with significant limitations. Objectives: Our aim was to (1) develop reference equations for static lung volumes and TL CO using the current American Thoracic Society/European Respiratory Society guidelines, and (2) compare the equations derived with those most commonly used. Methods: Healthy Caucasian subjects (234 males and 233 females) aged 18-91 years were recruited. All of them were healthy never smokers with a normal chest X-ray. Static lung volumes and TL CO were measured with a single-breath technique according to the latest guidelines. Results: Curvilinear regression prediction equations derived from the present study were compared with those that are most commonly used. Our reference equations in accordance with the latest studies show lower values for all static lung volume parameters and TL CO as well as a different way of deviation of those parameters (i.e. declining with age total lung capacity, TL CO age decline in both sex and functional residual capacity age rise in males). Conclusions: We suggest that old reference values of static lung volumes and TL CO should be updated, and our perception of deviation of some spirometric parameters should be revised. Our new reference curvilinear equations derived according to the latest guidelines could contribute to the updating by respiratory societies of old existing reference values and result in a better estimation of the lung function of contemporary populations with similar Caucasian characteristics. © 2015 S. Karger AG, Basel.

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

Bačeva, Katerina; Stafilov, Trajče, E-mail: trajcest@pmf.ukim.mk; Šajn, Robert

The aim of this study was to investigate the distribution of some toxic elements in topsoil and subsoil, focusing on the identification of natural and anthropogenic element sources in the small region of rare As–Sb–Tl mineralization outcrop and abandoned mine Allchar known for the highest natural concentration of Tl in soil worldwide. The samples of soil and sediments after total digestion were analyzed by inductively coupled plasma–mass spectrometry (ICP–MS) and inductively coupled plasma–atomic emission spectrometry (ICP–AES). Factor analysis (FA) was used to identify and characterize element associations. Six associations of elements were determined by the method of multivariate statistics: Rb–Ta–K–Nb–Ga–Sn–Ba–Bi–Li–Be–(La–Eu)–Hf–Zr–Zn–In–Pd–Ag–Pt–Mg;more » Tl–As–Sb–Hg; Te–S–Ag–Pt–Al–Sc–(Gd–Lu)–Y; Fe–Cu–V–Ge–Co–In; Pd–Zr–Hf–W–Be and Ni–Mn–Co–Cr–Mg. The purpose of the assessment was to determine the nature and extent of potential contamination as well as to broadly assess possible impacts to human health and the environment. The results from the analysis of the collected samples in the vicinity of the mine revealed that As and Tl elements have the highest median values. Higher median values for Sb are obviously as a result of the past mining activities and as a result of area surface phenomena in the past. - Highlights: • Soil and river sediments were analyzed from Sb–As–Tl Allchar locality. • An increased content of certain toxic elements for environment was determined. • Highest As and Tl contents are obtained in the close vicinity of Allchar mine. • River sediments portray 160 times higher content of Sb than EU values. • The results classify Allchar as probably the highest natural Tl-deposit worldwide.« less

On the use of LiF:Mg,Ti thermoluminescence dosemeters in space--a critical review.

PubMed

Horowitz, Y S; Satinger, D; Fuks, E; Oster, L; Podpalov, L

2003-01-01

The use of LiF:Mg,Ti thermoluminescence dosemeters (TLDs) in space radiation fields is reviewed. It is demonstrated in the context of modified track structure theory and microdosimetric track structure theory that there is no unique correlation between the relative thermoluminescence (TL) efficiency of heavy charged particles, neutrons of all energies and linear energy transfer (LET). Many experimental measurements dating back more than two decades also demonstrate the multivalued, non-universal, relationship between relative TL efficiency and LET. It is further demonstrated that the relative intensities of the dosimetric peaks and especially the high-temperature structure are dependent on a large number of variables, some controllable, some not. It is concluded that TL techniques employing the concept of LET (e.g. measurement of total dose, the high-temperature ratio (HTR) methods and other combinations of the relative TL efficiency of the various peaks used to estimate average Q or simulate Q-LET relationships) should be regarded as lacking a sound theoretical basis, highly prone to error and, as well, lack of reproducibility/universality due to the absence of a standardised experimental protocol essential to reliable experimental methodology.

The BiPo-3 detector for the measurement of ultra low natural radioactivities of thin materials

NASA Astrophysics Data System (ADS)

Barabash, A. S.; Basharina-Freshville, A.; Birdsall, E.; Blondel, S.; Blot, S.; Bongrand, M.; Boursette, D.; Brudanin, V.; Busto, J.; Caffrey, A. J.; Calvez, S.; Cascella, M.; Cebrián, S.; Cerna, C.; Cesar, J. P.; Chauveau, E.; Chopra, A.; Dafní, T.; De Capua, S.; Duchesneau, D.; Durand, D.; Egorov, V.; Eurin, G.; Evans, J. J.; Fajt, L.; Filosofov, D.; Flack, R.; Garrido, X.; Gómez, H.; Guillon, B.; Guzowski, P.; Holý, K.; Hodák, R.; Huber, A.; Hugon, C.; Iguaz, F. J.; Irastorza, I. G.; Jeremie, A.; Jullian, S.; Kauer, M.; Klimenko, A.; Kochetov, O.; Konovalov, S. I.; Kovalenko, V.; Lang, K.; Lemière, Y.; Le Noblet, T.; Liptak, Z.; Liu, X. R.; Loaiza, P.; Lutter, G.; Luzón, G.; Macko, M.; Mamedov, F.; Marquet, C.; Mauger, F.; Morgan, B.; Mott, J.; Nemchenok, I.; Nomachi, M.; Nova, F.; Ohsumi, H.; Oliviéro, G.; Ortiz de Solórzano, A.; Pahlka, R. B.; Pater, J.; Perrot, F.; Piquemal, F.; Povinec, P.; Přidal, P.; Ramachers, Y. A.; Remoto, A.; Richards, B.; Riddle, C. L.; Rukhadze, E.; Saakyan, R.; Salazar, R.; Sarazin, X.; Shitov, Yu.; Simard, L.; Šimkovic, F.; Smetana, A.; Smolek, K.; Smolnikov, A.; Söldner-Rembold, S.; Soulé, B.; Štekl, I.; Thomas, J.; Timkin, V.; Torre, S.; Tretyak, Vl. I.; Tretyak, V. I.; Umatov, V. I.; Vilela, C.; Vorobel, V.; Waters, D.; Žukauskas, A.

2017-06-01

The BiPo-3 detector, running at the Canfranc Underground Laboratory (Laboratorio Subterr&aposaneo de Canfranc, LSC, Spain) since 2013, is a low-radioactivity detector dedicated to measuring ultra low natural radionuclide contaminations of 208Tl (232Th chain) and 214Bi (238U chain) in thin materials. The total sensitive surface area of the detector is 3.6 m2. The detector has been developed to measure the radiopurity of the selenium double β-decay source foils of the SuperNEMO experiment. In this paper the design and performance of the detector, and results of the background measurements in 208Tl and 214Bi, are presented, and the validation of the BiPo-3 measurement with a calibrated aluminium foil is discussed. Results of the 208Tl and 214Bi activity measurements of the first enriched 82Se foils of the double β-decay SuperNEMO experiment are reported. The sensitivity of the BiPo-3 detector for the measurement of the SuperNEMO 82Se foils is Script A(208Tl) <2 μBq/kg (90% C.L.) and Script A(214Bi) <140 μBq/kg (90% C.L.) after 6 months of measurement.

Influences of body size and environmental factors on autumn downstream migration of bull trout in the Boise River, Idaho

USGS Publications Warehouse

Monnot, L.; Dunham, J.B.; Hoem, T.; Koetsier, P.

2008-01-01

Many fishes migrate extensively through stream networks, yet patterns are commonly described only in terms of the origin and destination of migration (e.g., between natal and feeding habitats). To better understand patterns of migration in bull trout,Salvelinus confluentus we studied the influences of body size (total length [TL]) and environmental factors (stream temperature and discharge) on migrations in the Boise River basin, Idaho. During the autumns of 2001-2003, we tracked the downstream migrations of 174 radio-tagged bull trout ranging in size from 21 to 73 cm TL. The results indicated that large bull trout (>30 cm) were more likely than small fish to migrate rapidly downstream after spawning in headwater streams in early autumn. Large bull trout also had a higher probability of arriving at the current terminus of migration in the system, Arrowrock Reservoir. The rate of migration by small bull trout was more variable and individuals were less likely to move into Arrowrock Reservoir. The rate of downstream migration by all fish was slower when stream discharge was greater. Temperature was not associated with the rate of migration. These findings indicate that fish size and environmentally related changes in behavior have important influences on patterns of migration. In a broader context, these results and other recent work suggest, at least in some cases, that commonly used classifications of migratory behavior may not accurately reflect the full range of behaviors and variability among individuals (or life stages) and environmental conditions. ?? Copyright by the American Fisheries Society 2008.

Early accelerated senescence of circulating endothelial progenitor cells in premature coronary artery disease patients in a developing country - a case control study.

PubMed

Vemparala, Kranthi; Roy, Ambuj; Bahl, Vinay Kumar; Prabhakaran, Dorairaj; Nath, Neera; Sinha, Subrata; Nandi, Pradipta; Pandey, Ravindra Mohan; Reddy, Kolli Srinath; Manhapra, Ajay; Lakshmy, Ramakrishnan

2013-11-19

The decreased number and senescence of circulating endothelial progenitor cells (EPCs) are considered markers of vascular senescence associated with aging, atherosclerosis, and coronary artery disease (CAD) in elderly. In this study, we explore the role of vascular senescence in premature CAD (PCAD) in a developing country by comparing the numerical status and senescence of circulating EPCs in PCAD patients to controls. EPCs were measured by flow cytometry in 57 patients with angiographically documented CAD, and 57 controls without evidence of CAD, recruited from random patients ≤ 50 years of age at All India Institute of Medical Sciences. EPC senescence as determined by telomere length (EPC-TL) and telomerase activity (EPC-TA) was studied by real time polymerase chain reaction (q PCR) and PCR- ELISA respectively. The number of EPCs (0.18% Vs. 0.039% of total WBCs, p < 0.0001), and EPC-TL (3.83 Vs. 5.10 kb/genome, p = 0.009) were markedly lower in PCAD patients compared to controls. These differences persisted after adjustment for age, sex, BMI, smoking and medications. EPC-TA was reduced in PCAD patients, but was statistically significant only after adjustment for confounding factors (1.81 Vs. 2.20 IU/cell, unadjusted p = 0.057, adjusted p = 0.044). We observed an association between increased vascular cell senescence with PCAD in a sample of young patients from India. This suggests that early accelerated vascular cell senescence may play an important mechanistic role in CAD epidemic in developing countries like India where PCAD burden is markedly higher compared to developed countries.

Summer habitat use by Columbia River redband trout in the Kootenai River drainage, Montana

USGS Publications Warehouse

Muhlfeld, Clint C.; Bennett, David H.

2001-01-01

The reported decline in the abundance, distribution, and genetic diversity of Columbia River redband trout Oncorhynchus mykiss gairdneri (a rainbow trout subspecies) has prompted fisheries managers to investigate their habitat requirements, identify critical habitat, and develop effective conservation and recovery programs. We analyzed the microhabitat, mesohabitat, and macrohabitat use and distribution of Columbia River redband trout by means of snorkel surveys in two watersheds in the Kootenai River drainage, Montana and Idaho, during the summers of 1997 and 1998. Juvenile (36–125 mm total length, TL) and adult (>=126 mm TL) fish preferred deep microhabitats (>=0.4 m) with low to moderate velocities (<=0.5 m/s) adjacent to the thalweg. Conversely, age-0 (<=35 mm) fish selected slow water (<=0.1 m/s) and shallow depths (<=0.2 m) located in lateral areas of the channel. Age-0, juvenile, and adult fish strongly selected pool mesohabitats and avoided riffles; juveniles and adults generally used runs in proportion to their availability. At the macrohabitat scale, density of Columbia River redband trout (35 mm) was positively related to the abundance of pools and negatively related to stream gradient. The pool: riffle ratio, gradient, and stream size combined accounted for 80% of the variation in density among 23 stream reaches in five streams. Our results demonstrate that low-gradient, medium-elevation reaches with an abundance of complex pools are critical areas for the production of Columbia River redband trout. These data will be useful in assessing the impacts of land-use practices on the remaining populations and may assist with habitat restoration or enhancement efforts.

Phase diagrams of the sections As/sub 2/S/sub 3/-Tl/sub 3/AsS/sub 4/, Tl/sub 3/AsS/sub 4/-S, and Tl/sub 3/AsS/sub 4/-Tl/sub 2/S of the ternary system As-Tl-S

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

Vorob'ev, Yu.I.; Velikova, N.G.; Kirilenko, V.V.

1987-12-01

Using DTA and XPA methods, microstructural investigations, and microhardness measurements, phase diagrams of the quasibinary sections As/sub 2/S/sub 3/-Tl/sub 3/AsS/sub 4/, Tl/sub 3/AsS/sub 4/-S, and Tl/sub 3/AsS/sub 4/-Tl/sub 2/S, are characterized by five ternary compounds Tl/sub 3/As/sub 5/S/sub 10/, Tl/sub 9/As/sub 5/S/sub 15/, Tl/sub 9/As/sub 3/S/sub 13/, Tl/sub 3/AsS/sub 6/, and Tl/sub 8/As/sub 2/S/sub 9/, which decompose by peritectic reactions at 198, 307, 408, 362, and 318/degree/C, respectively. Interplanar spacings and line intensities are given for the detected compounds. Glass formation is considered in the Tl-As-S system.

Dietary inflammatory index and telomere length in subjects with a high cardiovascular disease risk from the PREDIMED-NAVARRA study: cross-sectional and longitudinal analyses over 5 y1

PubMed Central

García-Calzón, Sonia; Zalba, Guillermo; Ruiz-Canela, Miguel; Shivappa, Nitin; Hébert, James R; Martínez, J Alfredo; Fitó, Montserrat; Gómez-Gracia, Enrique; Martínez-González, Miguel A; Marti, Amelia

2015-01-01

Background: Dietary factors can affect telomere length (TL), a biomarker of aging, through oxidation and inflammation-related mechanisms. A Dietary Inflammatory Index (DII) could help to understand the effect of the inflammatory potential of the diet on telomere shortening. Objective: This study aimed to determine the association of the DII with TL and to examine whether diet-associated inflammation could modify the telomere attrition rate after a 5-y follow-up of a Mediterranean dietary intervention. Design: This was a prospective study of 520 participants at high cardiovascular disease risk (mean ± SD age: 67.0 ± 6.0 y, 45% males) from the PREDIMED-NAVARRA (PREvención con DIeta MEDiterránea-NAVARRA) trial. Leukocyte TL was measured by quantitative real-time polymerase chain reaction at baseline and after 5 y of follow-up. The DII was calculated from self-reported data by using a validated 137-item food-frequency questionnaire. Results: Longer telomeres at baseline were found in participants who had a more anti-inflammatory diet (lowest DII score) (P-trend = 0.012). Longitudinal analyses further showed that a greater anti-inflammatory potential of the diet (i.e., a decrease in the DII) could significantly slow down the rate of telomere shortening. Moreover, the multivariable-adjusted OR for short telomeres (z score ≤20th percentile) was 1.80 (95% CI: 1.03, 3.17) in a comparison between the highest (proinflammatory) and the lowest (anti-inflammatory) DII tertiles. Similarly, a greater DII (greatest proinflammatory values) after a 5-y follow-up was associated with almost a 2-fold higher risk of accelerated telomere attrition compared with the highest decrease in DII (greatest anti-inflammatory values) during this period (P-trend = 0.025). Conclusions: This study showed both cross-sectional and longitudinal associations between the inflammatory potential of the diet and telomere shortening in subjects with a high cardiovascular disease risk. Our findings are consistent with, but do not show, a beneficial effect of adherence to an anti-inflammatory diet on aging and health by slowing down telomere shortening. These results suggest that diet might play a key role as a determinant of TL through proinflammatory or anti-inflammatory mechanisms. This trial was registered at controlled-trials.com as ISRCTN35739639. PMID:26354530

Dietary inflammatory index and telomere length in subjects with a high cardiovascular disease risk from the PREDIMED-NAVARRA study: cross-sectional and longitudinal analyses over 5 y.

PubMed

García-Calzón, Sonia; Zalba, Guillermo; Ruiz-Canela, Miguel; Shivappa, Nitin; Hébert, James R; Martínez, J Alfredo; Fitó, Montserrat; Gómez-Gracia, Enrique; Martínez-González, Miguel A; Marti, Amelia

2015-10-01

Dietary factors can affect telomere length (TL), a biomarker of aging, through oxidation and inflammation-related mechanisms. A Dietary Inflammatory Index (DII) could help to understand the effect of the inflammatory potential of the diet on telomere shortening. This study aimed to determine the association of the DII with TL and to examine whether diet-associated inflammation could modify the telomere attrition rate after a 5-y follow-up of a Mediterranean dietary intervention. This was a prospective study of 520 participants at high cardiovascular disease risk (mean ± SD age: 67.0 ± 6.0 y, 45% males) from the PREDIMED-NAVARRA (PREvención con DIeta MEDiterránea-NAVARRA) trial. Leukocyte TL was measured by quantitative real-time polymerase chain reaction at baseline and after 5 y of follow-up. The DII was calculated from self-reported data by using a validated 137-item food-frequency questionnaire. Longer telomeres at baseline were found in participants who had a more anti-inflammatory diet (lowest DII score) (P-trend = 0.012). Longitudinal analyses further showed that a greater anti-inflammatory potential of the diet (i.e., a decrease in the DII) could significantly slow down the rate of telomere shortening. Moreover, the multivariable-adjusted OR for short telomeres (z score ≤20th percentile) was 1.80 (95% CI: 1.03, 3.17) in a comparison between the highest (proinflammatory) and the lowest (anti-inflammatory) DII tertiles. Similarly, a greater DII (greatest proinflammatory values) after a 5-y follow-up was associated with almost a 2-fold higher risk of accelerated telomere attrition compared with the highest decrease in DII (greatest anti-inflammatory values) during this period (P-trend = 0.025). This study showed both cross-sectional and longitudinal associations between the inflammatory potential of the diet and telomere shortening in subjects with a high cardiovascular disease risk. Our findings are consistent with, but do not show, a beneficial effect of adherence to an anti-inflammatory diet on aging and health by slowing down telomere shortening. These results suggest that diet might play a key role as a determinant of TL through proinflammatory or anti-inflammatory mechanisms. This trial was registered at controlled-trials.com as ISRCTN35739639. © 2015 American Society for Nutrition.

Spontaneous Tl(I)-to-Tl(III) oxidation in dynamic heterobimetallic Hg(II)/Tl(I) porphyrin complexes.

PubMed

Ndoyom, Victoria; Fusaro, Luca; Roisnel, Thierry; Le Gac, Stéphane; Boitrel, Bernard

2016-01-11

Strapped heterobimetallic Hg(II)/Tl(I) porphyrin complexes, with both metal ions bridged by the N-core in a dynamic way, undergo spontaneous Tl(I)-to-Tl(III) oxidation leading to a mono-Tl(III) complex and a mixed valence Tl(I)/Tl(III) bimetallic complex. It provides a new opportunity to tune metal ion translocations in bimetallic porphyrin systems.

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.

Host size-dependent anisakid infection in Baltic cod Gadus morhua associated with differential food preferences.

PubMed

Zuo, Shaozhi; Huwer, Bastian; Bahlool, Qusay; Al-Jubury, Azmi; Daugbjerg Christensen, Nanna; Korbut, Rozalia; Kania, Per; Buchmann, Kurt

2016-06-15

A significant increase in the infection level of Baltic cod Gadus morhua with the anisakid nematode larvae Contracaecum osculatum and Pseudoterranova decipiens has been recorded during recent years due to the expanding local population of grey seals Halichoerus grypus, which act as final hosts for these parasites. Here, we report from an investigation of 368 cod (total length [TL] 6-49 cm; caught in ICES Subdivision 25) that the infection level of juvenile cod (TL 6-30 cm) with larvae of C. osculatum and P. decipiens is absent or very low, whereas it increases drastically in larger cod (TL 31-48 cm). A third nematode Hysterothylacium aduncum was rarely found. The study indicates that the prey animals for large cod act as transport hosts for the parasite larvae. Analyses of stomach contents of cod caught in the same area (2007-2014) showed that small benthic organisms (including polychaetes Harmothoë sarsi) are preferred food items by small cod, the isopod Saduria entomon is taken by all size classes, and sprat Sprattus sprattus are common prey items for cod larger than 30 cm. Parasitological investigations (microscopic and molecular analyses) of H. sarsi (100 specimens) and S. entomon (40 specimens) did not reveal infection in these invertebrates, but 11.6% of sprat (265 specimens examined) was shown to be infected with 1-8 C. osculatum third stage larvae per fish. Analyses of sprat stomach contents confirmed that copepods and cladocerans are the main food items of sprat. These observations suggest that the C. osculatum life cycle in the Baltic Sea includes grey seals as final hosts, sprat as the first transport host and cod as second transport host. It may be speculated that sprat obtain infection by feeding on copepods and/or cladocerans, which could serve as the first intermediate hosts. One cannot exclude the possibility that the size-dependent C. osculatum infection of cod may contribute (indirectly or directly) to the differential mortality of larger cod (>38 cm) compared to smaller cod (<30 cm) recently recorded in the Baltic cod population.

Sex assignment of lake sturgeon (Acipenser fluvescens) based on plasma sex hormone and vitellogenin levels

USGS Publications Warehouse

Craig, J.M.; Papoulias, D.M.; Thomas, M.V.; Annis, M.L.; Boase, J.

2009-01-01

This study focused on identifying the sex of lake sturgeon by measuring the sex hormones estradiol and testosterone, and the phosphoprotein vitellogenin (Vtg) in blood plasma by radioimmunoassay and enzyme-linked immunosorbent assay, respectively, and evaluating these techniques as tools in lake sturgeon population management. Surveys of the St Clair River (SCR) lake sturgeon population have characterized it as rebounding by having steady or increasing recruitment since 1997. However, researchers have not been able to effectively determine the sex for most of the sturgeon they capture because few fish caught during surveys are releasing gametes. A total of 115 fish were sampled from May through June in 2004 and 2005 from the SCR, Michigan, USA. Of these, only four females and eight males were verified (i.e. they were releasing gametes at time of capture), resulting in very few fish with which to validate blood hormone and Vtg biomarkers of sex. Fifty-six percent of the fish were assigned a sex designation based on biomarker criteria. Correspondence between actual gonadal sex and biomarker-directed classification was good for the small subset of fish for which gonadal sex was definitively determined. Moreover, application of the steroid values in a predictive sex assignment model developed for white sturgeon misclassified only the same two fish that were misclassified with the steroid and Vtg biomarkers. The experimental results suggest a sex ratio of 1 : 2.7 (F:M), however more conclusive methods are needed to confirm this ratio because so few fish were available for sex validation. Of the 43 males, 14 were within the legal slot limit, 11 were smaller than 1067 mm total length (TL), and 18 were larger than 1270 mm TL. All 15 females were larger than 1270 mm TL, and thus protected by the slot limit criteria. Considering that lake sturgeon are threatened in Michigan, an advantage to using blood plasma assays was that fish were not harmed, and sample collection was quick, simple, and inexpensive. However, because a sufficiently large number of fish could not be validated for gonadal sex due to handling restrictions given the fish's protected status, assignment of sex is not based on a robust multi-variate model. An immediate alternative may be to use other non-invasive field methods (e.g. ultrasound, fiber-optic endoscope) to provide a more timely classification while establishing well-validated plasma hormone and Vtg-based predictive models for sex assignment of lake sturgeon. ?? 2009 Blackwell Verlag, Berlin.

Medium-chain triglyceride-rich enteral nutrition is more effective than low-fat enteral nutrition in rat colitis, but is equal in enteritis.

PubMed

Tsujikawa, T; Ohta, N; Nakamura, T; Yasuoka, T; Satoh, J; Fukunaga, T; Itohi, A; Uda, K; Ihara, T; Andoh, A; Sasaki, M; Fujiyama, Y; Bamba, T

2001-10-01

Although enteral nutrition (EN) therapy for Crohn's disease has been confirmed to be as effective as steroid therapy, the precise mechanism responsible for the effects of EN remains unclear, although some of the therapeutic effects of EN are believed to be due to a low dietary fat content. In order to elucidate the influence of fat in EN, it is important to investigate not only the quantity of fat, but also the source of the fat. We compared two enteral nutritional formulae: Elental (Ajinomoto) (elemental diet; ED), which contains only 1.5% fat, provided as long-chain triglycerides (LCT), versus Twinline (Snow Brand Milk Products) (TL), which contains a high percentage of fat (20.4%), provided mainly as medium-chain triglycerides (MCT). These formulae were tested on rat enteritis and rat colitis induced by trinitrobenzene sulfonic acid (TNBS). Both ED and TL reduced the manifestations of enteritis. TL had a stronger anti-inflammatory effect than ED for colitis. TL also had nutritional advantages as compared with ED, as shown by the total serum protein in the TL group being significantly higher than that in the ED group. The results indicate that intraluminal MCT is suitable as a fat energy source during intestinal inflammation in rats. We suggest that Twinline may be more useful to improve nutritional status and to reduce the mucosal inflammation in rat colitis, but that Twinline is equal in effect to Elental for rat enteritis.

The Dose-Response Relationship Between Training Load and Aerobic Fitness in Academy Rugby Union Players.

PubMed

Taylor, Richard J; Sanders, Dajo; Myers, Tony; Abt, Grant; Taylor, Celia A; Akubat, Ibrahim

2018-02-01

To identify the dose-response relationship between measures of training load (TL) and changes in aerobic fitness in academy rugby union players. Training data from 10 academy rugby union players were collected during a 6-wk in-season period. Participants completed a lactate-threshold test that was used to assess VO 2 max, velocity at VO 2 max, velocity at 2 mmol/L (lactate threshold), and velocity at 4 mmol/L (onset of lactate accumulation; vOBLA) as measures of aerobic fitness. Internal-TL measures calculated were Banister training impulse (bTRIMP), Edwards TRIMP, Lucia TRIMP, individualized TRIMP (iTRIMP), and session RPE (sRPE). External-TL measures calculated were total distance, PlayerLoad™, high-speed distance >15 km/h, very-high-speed distance >18 km/h, and individualized high-speed distance based on each player's vOBLA. A second-order-regression (quadratic) analysis found that bTRIMP (R 2  = .78, P = .005) explained 78% of the variance and iTRIMP (R 2  = .55, P = .063) explained 55% of the variance in changes in VO 2 max. All other HR-based internal-TL measures and sRPE explained less than 40% of variance with fitness changes. External TL explained less than 42% of variance with fitness changes. In rugby players, bTRIMP and iTRIMP display a curvilinear dose-response relationship with changes in maximal aerobic fitness.

Lightweight acoustic treatments for aerospace applications

NASA Astrophysics Data System (ADS)

Naify, Christina Jeanne

2011-12-01

Increase in the use of composites for aerospace applications has the benefit of decreased structural weight, but at the cost of decreased acoustic performance. Stiff, lightweight structures (such as composites) are traditionally not ideal for acoustic insulation applications because of high transmission loss at low frequencies. A need has thus arisen for effective sound insulation materials for aerospace and automotive applications with low weight addition. Current approaches, such as the addition of mass law dominated materials (foams) also perform poorly when scaled to small thickness and low density. In this dissertation, methods which reduce sound transmission without adding significant weight are investigated. The methods presented are intended to be integrated into currently used lightweight structures such as honeycomb sandwich panels and to cover a wide range of frequencies. Layering gasses of differing acoustic impedances on a panel substantially reduced the amount of sound energy transmitted through the panel with respect to the panel alone or an equivalent-thickness single species gas layer. The additional transmission loss derives from successive impedance mismatches at the interfaces between gas layers and the resulting inefficient energy transfer. Attachment of additional gas layers increased the transmission loss (TL) by as much as 17 dB at high (>1 kHz) frequencies. The location and ordering of the gasses with respect to the panel were important factors in determining the magnitude of the total TL. Theoretical analysis using a transfer matrix method was used to calculate the frequency dependence of sound transmission for the different configurations tested. The method accurately predicted the relative increases in TL observed with the addition of different gas layer configurations. To address low-frequency sound insulation, membrane-type locally resonant acoustic materials (LRAM) were fabricated, characterized, and analyzed to understand their acoustic response. Acoustic metamaterials with negative dynamic mass density have been shown to demonstrate a significant (5x) increase in TL over mass law predictions for a narrow band (100Hz) at low frequencies (100--1000Hz). The peak TL frequency can be tuned to specific values by varying the membrane and mass properties. TL magnitude as a function of frequency was measured for variations of the mass magnitude and membrane tension using an impedance tube setup. The dynamic properties of membranes constructed from different materials and thicknesses were measured and compared to the results of coupled field acoustic-structural finite element analysis (FEA) modeling to understand the role of tension and element quality factor. To better comprehend the mechanism(s) responsible for the TL peak, a laser vibrometer was used to map the out-of-plane dynamic response of the structure under acoustic loading at discrete frequencies. Negative dynamic mass was experimentally demonstrated at the peak TL frequency. The scale-up of the acoustic metamaterial structure was explored by examining the behavior of multiple elements arranged in arrays. Single membranes were stretched over rigid frame supports and masses were attached to the center of each divided cell. TL behavior was measured for multiple configurations with different magnitudes of mass distributed across each of the cell membranes in the array resulting in a multi-peak TL profile. To better understand scale-up issues, the effect of the frame structure compliance was evaluated, and more compliant frames resulted in a reduction in TL peak frequency bandwidth. In addition, displacement measurements of frames and membranes were performed using a laser vibrometer. The measured TL of the multi-celled structure was compared with TL behavior predicted by FEA to understand the role of non-uniform mass distribution and frame compliance. TL of membrane-type LRAM with added ring masses was analyzed using both finite element analysis and experimental techniques. The addition of a ring mass to the structure either increased the bandwidth of the TL peak, or introduced multiple peaks, depending on the number of rings, the distribution of mass between the center and ring masses, and radii of the rings. FEA was used to predict TL behavior of several ring configurations, and TL for these configurations was measured to validate the model predictions. Finally, FEA was used to predict the mode shapes of the structure under single-frequency excitation to understand the mechanisms responsible for the TL peaks.

Birth of common shovelnose rays (Glaucostegus typus) under captive conditions.

PubMed

Timm, Lori L; Carter, Joshua E; Frey, Joshua; Prappas, James; Wells, R J David

2014-01-01

The common shovelnose ray (Glaucostegus typus) is a poorly studied species of the Rhinobatidae family that occurs throughout the Indo-West Pacific. Although common in aquariums throughout the United States, there are currently no records of captive birth events. In 2013, a female common shovelnose ray housed at the Downtown Aquarium in Houston, Texas, USA gave birth to eleven pups. Although all pups were stillborn, this event demonstrates that it is possible to breed common shovelnose rays in a controlled environment. The single female and two male common shovelnose rays at the aquarium are of sexually mature size (between 206 and 240 cm total length, TL), demonstrate mating behaviors, and provide an excellent opportunity to investigate the reproductive biology of this species. Captive environmental conditions of the birth enclosure may be useful in replicating the birthing event in order to develop a breeding program that could potentially relieve collection pressures on wild populations of guitarfish given their vulnerable status. © 2014 Wiley Periodicals, Inc.

Hole doping and structural transformation in CsTl1-xHgxCl3.

PubMed

Retuerto, Maria; Yin, Zhiping; Emge, Thomas J; Stephens, Peter W; Li, Man-Rong; Sarkar, Tapati; Croft, Mark C; Ignatov, Alexander; Yuan, Z; Zhang, S J; Jin, Changqing; Paria Sena, Robert; Hadermann, Joke; Kotliar, Gabriel; Greenblatt, Martha

2015-02-02

CsTlCl(3) and CsTlF(3) perovskites have been theoretically predicted to be superconductors when properly hole-doped. Both compounds have been previously prepared as pure compounds: CsTlCl(3) in a tetragonal (I4/m) and a cubic (Fm3̅m) perovskite polymorph and CsTlF(3) as a cubic perovskite (Fm3̅m). In this work, substitution of Tl in CsTlCl(3) with Hg is reported, in an attempt to hole-dope the system and induce superconductivity. The whole series CsTl(1-x)HgxCl(3) (x = 0.0, 0.1, 0.2, 0.4, 0.6, and 0.8) was prepared. CsTl(0.9)Hg(0.1)Cl(3) is tetragonal as the more stable phase of CsTlCl(3). However, CsTl(0.8)Hg(0.2)Cl(3) is already cubic with the space group Fm3̅m and with two different positions for Tl(+) and Tl(3+). For x = 0.4 and 0.5, solid solutions could not be formed. For x ≥ 0.6, the samples are primitive cubic perovskites with one crystallographic position for Tl(+), Tl(3+), and Hg(2+). All of the samples formed are insulating, and there is no signature of superconductivity. X-ray absorption spectroscopy indicates that all of the samples have a mixed-valence state of Tl(+) and Tl(3+). Raman spectroscopy shows the presence of the active Tl-Cl-Tl stretching mode over the whole series and the intensity of the Tl-Cl-Hg mode increases with increasing Hg content. First-principle calculations confirmed that the phases are insulators in their ground state and that Hg is not a good dopant in the search for superconductivity in this system.

Enhancement of the anti-inflammatory activity of temporin-1Tl-derived antimicrobial peptides by tryptophan, arginine and lysine substitutions.

PubMed

Rajasekaran, Ganesan; Kamalakannan, Radhakrishnan; Shin, Song Yub

2015-10-01

Temporin-1Tl (TL) is a 13-residue frog antimicrobial peptide (AMP) exhibiting potent antimicrobial and anti-inflammatory activity. To develop novel AMP with improved anti-inflammatory activity and antimicrobial selectivity, we designed and synthesized a series of TL analogs by substituting Trp, Arg and Lys at selected positions. Except for Escherichia coli and Staphylococcus epidermidis, all TL analogs exhibited retained or increased antimicrobial activity against seven bacterial strains including three methicillin-resistant Staphylococcus aureus strains compared with TL. TL-1 and TL-4 showed a little increase in antimicrobial selectivity, while TL-2 and TL-3 displayed slightly decreased antimicrobial selectivity because of their about twofold increased hemolytic activity. All TL analogs demonstrated greatly increased anti-inflammatory activity, evident by their higher inhibition of the production tumor necrosis factor-α (TNF-α) and nitric oxide and the mRNA expression of inducible nitric oxide synthase and TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells, compared with TL. Taken together, the peptide anti-inflammatory activity is as follows: TL-2 ≈ TL-3 ≈ TL-4 > TL-1 > TL. In addition, LPS binding ability of the peptides corresponded with their anti-inflammatory activity. These results apparently suggest that the anti-inflammatory activity of TL analogs is associated with the direct binding ability between these peptides and LPS. Collectively, our designed TL analogs possess improved anti-inflammatory activity and retain antimicrobial activity without a significant increase in hemolysis. Therefore, it is evident that our TL analogs constitute promising candidates for the development of peptide therapeutics for gram-negative bacterial infection. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

Tracing thallium contamination in soils using isotopes

NASA Astrophysics Data System (ADS)

Vaněk, Aleš; Grösslová, Zuzana; Mihaljevič, Martin; Ettler, Vojtěch; Trubač, Jakub; Teper, Leslaw; Cabala, Jerzy; Rohovec, Jan; Penížek, Vít; Zádorová, Tereza; Pavlů, Lenka; Holubík, Ondřej; Drábek, Ondřej; Němeček, Karel; Houška, Jakub; Ash, Christopher

2017-04-01

We report the thallium (Tl) isotope record in moderately contaminated soils, which have been historically affected by emissions from coal-fired power plants. Our findings clearly demonstrate that Tl of anthropogenic (high-temperature) origin with light isotope composition was deposited onto the studied soils, where heavier Tl (ɛ205Tl -1) naturally occurs. The results show a positive linear relationship (R2 = 0.71) between 1/Tl and the isotope record, as determined for all the soils and bedrocks, also indicative of binary Tl mixing between two dominant reservoirs. We also identified significant Tl isotope variations within the products from coal combustion and thermo-desorption experiments with local Tl-rich coal pyrite. Bottom ash exhibited the heaviest Tl isotope composition (ɛ205Tl 0), followed by fly ash (ɛ205Tl between -2.5 and -2.8) and volatile Tl fractions (ɛ205Tl between -6.2 and -10.3), suggesting partial Tl isotope fractionations. Despite the evident role of soil processes in the isotope redistribution, we demonstrate that Tl contamination can be traced in soils, and propose that the isotope data represent a possible tool to aid our understanding of post-depositional Tl dynamics in surface environments for the future. This research was supported by the Czech Science Foundation (grant no. 14-01866S and 17-03211S).

Interaction of Tl +3 with mononucleotides: metal ion binding and sugar conformation

NASA Astrophysics Data System (ADS)

Nafisi, Sh.; Mohajerani, N.; Hadjiakhoondi, A.; Monajemi, M.; Garib, F.

2001-05-01

The interaction of Tl 3+ with sodium salts of adenosine-5'-monophosphate (5'-AMP), guanosine-5'-monophosphate (5'-GMP), cytidine-5'-monophosphate (5'-CMP), thymidine 5'-monophosphate (5'-dTMP) in ratios 1 and 2 have been studied in neutral pH. The solid complexes were isolated and characterized by Fourier transform infrared (FTIR) and 1H NMR spectroscopy. In the Tl 2(AMP) 3, Tl 3+ binds directly to N-7 and indirectly to the N-1 position of the pyrimidine ring and phosphate group with sugar moiety in C2'-endoanti. The crystalline salt of Tl 2(GMP) 3 show direct Tl-N-7 and Tl-PO 3(inner-sphere) binding. The conformation of ribose moiety in Tl 2(GMP) 3 is C3'-endoanti. In the Tl 2(CMP) 3, Tl 3+ bind directly to N-3 and PO32- (inner-sphere). The conformation of ribose moiety in Tl 2(CMP) 3 is C2'-endoanti. In the Tl 2(dTMP) 3, Tl 3+ bind indirectly to carbonyl group. The sugar moiety in Tl 2(dTMP) 3 is C3'-endoanti.

(99m)Tc-MDP bone scintigraphy of the hand: comparing the use of novel cadmium zinc telluride (CZT) and routine NaI(Tl) detectors.

PubMed

Koulikov, Victoria; Lerman, Hedva; Kesler, Mikhail; Even-Sapir, Einat

2015-12-01

Cadmium zinc telluride (CZT) solid-state detectors have been recently introduced in the field of nuclear medicine in cardiology and breast imaging. The aim of the current study was to evaluate the performance of the novel detectors (CZT) compared to that of the routine NaI(Tl) in bone scintigraphy. A dual-headed CZT-based camera dedicated originally to breast imaging has been used, and in view of the limited size of the detectors, the hands were chosen as the organ for assessment. This is a clinical study. Fifty-eight consecutive patients (total 116 hands) referred for bone scan for suspected hand pathology gave their informed consent to have two acquisitions, using the routine camera and the CZT-based camera. The latter was divided into full-dose full-acquisition time (FD CZT) and reduced-dose short-acquisition time (RD CZT) on CZT technology, so three image sets were available for analysis. Data analysis included comparing the detection of hot lesions and identification of the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints. A total of 69 hot lesions were detected on the CZT image sets; of these, 61 were identified as focal sites of uptake on NaI(Tl) data. On FD CZT data, 385 joints were identified compared to 168 on NaI(Tl) data (p < 0.001). There was no statistically significant difference in delineation of joints between FD and RD CZT data as the latter identified 383 joints. Bone scintigraphy using a CZT-based gamma camera is associated with improved lesion detection and anatomic definition. The superior physical characteristics of this technique raised a potential reduction in administered dose and/or acquisition time without compromising image quality.

Electroglottographic Comparison of Voice Outcomes in Patients With Advanced Laryngopharyngeal Cancer Treated by Chemoradiotherapy or Total Laryngectomy

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

Kazi, Rehan; Institute of Cancer Research, London; Venkitaraman, Ramachandran

2008-02-01

Purpose: To conduct prospective electroglottographic analyses of voice outcomes after radical chemoradiotherapy for locally advanced laryngopharyngeal cancers and to compare them with patients who have undergone total laryngectomy (TL). Patients and Methods: Twenty-one patients (19 male, 2 female, median age [range] 65 [50-85] years) with Stage III/IV laryngopharyngeal cancer received induction chemotherapy followed by radical chemoradiotherapy. Electroglottography, using the sustained vowel /i/ and connected speech, was performed before treatment and 1, 6, and 12 months after treatment. In addition, single voice recordings were taken from 21 patients (16 male, 5 female, aged 65 [50-84] years) who had undergone TL andmore » surgical voice restoration and from 21 normal controls (18 male, 3 female, aged 65 [33-80] years). Results: Before treatment the vocal measures for the chemoradiotherapy patients were significantly different from normal controls in jitter (p = 0.02), maximum phonation time (MPT) (p = 0.001), and words per minute (WPM) (p = 0.01). At 12 months after treatment MPT and WPM had normalized, but jitter and normalized noise energy were significantly worse than in normal controls. Comparison of voice outcomes at 12 months for chemoradiotherapy patients revealed superiority over the TL group in all parameters except MPT (18.2 s vs. 10.4 s, p = 0.06). Analysis of the recovery of voice up to 12 months after treatment revealed progressive improvement in most electroglottographic measures. Conclusions: This prospective study demonstrates significantly better outcome for patients treated with chemoradiotherapy as compared with TL. Progressive normalization of many voice parameters occurs over the 12 months following chemoradiotherapy.« less

Training-Load Distribution in Endurance Runners: Objective Versus Subjective Assessment.

PubMed

Manzi, Vincenzo; Bovenzi, Antonio; Castagna, Carlo; Sinibaldi Salimei, Paola; Volterrani, Maurizio; Iellamo, Ferdinando

2015-11-01

To assess the distribution of exercise intensity in long-distance recreational athletes (LDRs) preparing for a marathon and to test the hypothesis that individual perception of effort could provide training responses similar to those provided by standardized training methodologies. Seven LDRs (age 36.5 ± 3.8 y) were followed during a 5-mo training period culminating with a city marathon. Heart rate at 2.0 and 4.0 mmol/L and maximal heart rate were used to establish 3 intensity training zones. Internal training load (TL) was assessed by training zones and TRIMPi methods. These were compared with the session-rating-of-perceived-exertion (RPE) method. Total time spent in zone 1 was higher than in zones 2 and 3 (76.3% ± 6.4%, 17.3% ± 5.8%, and 6.3% ± 0.9%, respectively; P = .000 for both, ES = 0.98, ES = 0.99). TL quantified by session-RPE provided the same result. The comparison between session-RPE and training-zones-based methods showed no significant difference at the lowest intensity (P = .07, ES = 0.25). A significant correlation was observed between TL RPE and TL TRIMPi at both individual and group levels (r = .79, P < .001). There was a significant correlation between total time spent in zone 1 and the improvement at the running speed of 2 mmol/L (r = .88, P < .001). A negative correlation was found between running speed at 2 mmol/L and the time needed to complete the marathon (r = -.83, P < .001). These findings suggest that in recreational LDRs most of the training time is spent at low intensity and that this is associated with improved performances. Session-RPE is an easy-to-use training method that provides responses similar to those obtained with standardized training methodologies.

Effective removal of trace thallium from surface water by nanosized manganese dioxide enhanced quartz sand filtration.

PubMed

Huangfu, Xiaoliu; Ma, Chengxue; Ma, Jun; He, Qiang; Yang, Chun; Zhou, Jian; Jiang, Jin; Wang, Yaan

2017-12-01

Thallium (Tl) has drawn wide concern due to its high toxicity even at extremely low concentrations, as well as its tendency for significant accumulation in the human body and other organisms. The need to develop effective strategies for trace Tl removal from drinking water is urgent. In this study, the removal of trace Tl (0.5 μg L -1 ) by conventional quartz sand filtration enhanced by nanosized manganese dioxide (nMnO 2 ) has been investigated using typical surface water obtained from northeast China. The results indicate that nMnO 2 enhanced quartz sand filtration could remove trace Tl(I) and Tl(III) efficiently through the adsorption of Tl onto nMnO 2 added to a water matrix and onto nMnO 2 attached on quartz sand surfaces. Tl(III)-HA complexes might be responsible for higher residual Tl(III) in the effluent compared to residual Tl(I). Competitive Ca 2+ cations inhibit Tl removal to a certain extent because the Ca 2+ ions will occupy the Tl adsorption site on nMnO 2 . Moreover, high concentrations of HA (10 mgTOC L -1 ), which notably complexes with and dissolves nMnO 2 (more than 78%), resulted in higher residual Tl(I) and Tl(III). Tl(III)-HA complexes might also enhance Tl(III) penetration to a certain extent. Additionally, a higher pH level could enhance the removal of trace Tl from surface water. Finally, a slight increase of residual Tl was observed after backwash, followed by the reduction of the Tl concentration in the effluent to a "steady" state again. The knowledge obtained here may provide a potential strategy for drinking water treatment plants threatened by trace Tl. Copyright © 2017. Published by Elsevier Ltd.

ISOANTIGENS OF THE H-2 AND Tla LOCI OF THE MOUSE

PubMed Central

Boyse, Edward A.; Stockert, Elisabeth; Old, Lloyd J.

1968-01-01

H-2 and TL isoantigens of the mouse are specified by the closely linked genetic loci H-2 and Tla. A. study of their representation on thymocytes was performed in order to reveal any interactions between the determinant genes or their products affecting the synthesis or disposition of these components of the thymocyte surface. The method employed was quantitative absorption of cytotoxic antibody by viable thymocytes. The phenotypic expression of TL antigens was found to reduce the demonstrable amount of certain H-2 antigens to as little as 34% of the quantity demonstrable on TL- thymocytes. A reduction was observed in all three H-2 types tested, (H-2b, H-2a, and H-2k). As antigenic modulation (change of TL phenotype from TL+ to TL-, produced by TL antibody) is known to entail a compensatory increase in H-2(D) antigen, it is concluded that the TL phenotype, rather than the Tla genotype, influences the surface representation of H-2 antigens. The two known TL+ phenotypes of thymocytes (TL.2 and TL.1,2,3) depress H-2 equally. The H-2 specificities affected are those determined by the D end of the E-2 locus, which is adjacent to Tla; antigens of the K end, which is distal to Tla, are not depressed. The reduction of demonstrable H-2 antigen on the thymocytes of TL+ x TL- progeny is half that of thymocytes of TL+ x TL+ progeny and the reduction affects equally the products of both H-2 alleles (cis and trans in relation to Tla), indicating that the mechanism of H-2 reduction by TL is extrachromosomal. Whether it involves diminished synthesis of H-2 or steric masking by TL at the cell membrane is unknown, but in either case the reciprocal relation of TL and H-2(D) antigens implies that they probably occupy adjacent positions on thymocytes and that the gene order, H-2(K): H-2(D):Tla is reflected in cell surface structure. Extrachromosomal interaction, apparently involving control of synthesis, occurs also within the TL system of antigens. Thymocytes of TL.2 x TL.1,2,3 progeny express the full homozygous quantity of antigens TL.1 and TL.3 (but not of TL.2), in contrast to the half-quantity present in thymocytes of TL- x TL.1,2,3 progeny. Another example of interaction is implicit in the finding that thymocytes of TL-1,2,3 x TL.1,2,3 progeny have more TL.2 antigen than thymocytes of TL.2 x TL.2 progeny, but in this instance there is nothing to indicate whether the mechanism is chromosomal or extrachromosomal. Thus the quantitative surface representation of at least some H-2 and TL antigens is influenced by the cellular complement of H-2:Tla genes as a whole. Comparison of H-2 heterozygous thymocytes with H-2 homozygous thymocytes in quantitative absorption tests shows (a) more than the expected 50% of each parental-type H-2 antigen on heterozygous cells, and (b) a greater suppression of H-2 by TL in H-2 heterozygotes in comparison with H-2 homozygotes. Both results may be explained on the basis of differences in the density of H-2 antigenic sites and consequent differences in the efficiency of absorption of H-2 antibody. These considerations may be useful in other contexts, e.g. in estimating the representation of Rh antigens on the red cells of human subjects homozygous and heterozygous for Rh components. PMID:5662018

Thallium pollution in China: A geo-environmental perspective.

PubMed

Xiao, Tangfu; Yang, Fei; Li, Shehong; Zheng, Baoshan; Ning, Zengping

2012-04-01

It is well known that thallium (Tl) is a non-essential and toxic metal to human health, but less is known about the geo-environmentally-induced Tl pollution and its associated health impacts. High concentrations of Tl that are primarily associated with the epithermal metallogenesis of sulfide minerals have the potential of producing Tl pollution in the environment, which has been recognized as an emerging pollutant in China. This paper aims to review the research progress in China on Tl pollution in terms of the source, mobility, transportation pathway, and health exposure of Tl and to address the environmental concerns on Tl pollution in a geo-environmental perspective. Tl associated with the epithermal metallogenesis of sulfide minerals has been documented to disperse readily and accumulate through the geo-environmental processes of soil enrichment, water transportation and food crop growth beyond a mineralized zone. The enrichments of Tl in local soil, water, and crops may result in Tl pollution and consequent adverse health effects, e.g. chronic Tl poisoning. Investigation of the baseline Tl in the geo-environment, proper land use and health-related environmental planning and regulation are critical to prevent the Tl pollution. Examination of the human urinary Tl concentration is a quick approach to identify exposure of Tl pollution to humans. The experiences of Tl pollution in China can provide important lessons for many other regions in the world with similar geo-environmental contexts because of the high mobility and toxicity of Tl. Copyright © 2011 Elsevier B.V. All rights reserved.

Scaled Hartree-Fock force field calculations for organothallium compounds: Normal-mode analysis for TlCH sub 3 Tl(CH sub 3 ) sub 2 sup + , Tl(CH sub 3 ) sub 3 , Tl(CH sub 3 ) sub 2 Br, and Tl(CH sub 3 ) sub 4 sup minus

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

Schwerdtfeger, P.; Bowmaker, G.A.; Boyd, P.D.W.

1990-02-01

In a recent paper we presented Hartree-Fock (HF) calculations for aliphatic organothallium compounds. The diagonal HF force constants obtained from a Fletcher-Powell geometry optimization are now used for a normal-mode analysis of TlCH{sub 3}, Tl(CH{sub 3}){sub 2}{sup +}, Tl(CH{sub 3}){sub 3}, Tl(CH{sub 3}){sub 2}Br, and Tl(CH{sub 3}){sub 4}{sup {minus}}. In order to calculate frequencies comparable to experimental values, the HF force field has been scaled by using scaling factors obtained from experimental infrared and Raman measurements on Tl(CH{sub 3}){sub 2}{sup +} and TlBr. The vibrational spectra of Tl(CH{sub 3}){sub 2}{sup +} were remeasured (infrared and Raman) in order to obtainmore » an accurate force field. Predictions are made for the vibrational spectrum of the as yet undetected TlCH{sub 3} molecule. Experimental infrared and Raman results for Tl(CH{sub 3}){sub 3} compare reasonably well with our calculated frequencies. Relativistic and correlation effects are analyzed for the vibrational frequencies of Tl(CH{sub 3}){sub 2}{sup +}.« less

Optimization and comparison of simultaneous and separate acquisition protocols for dual isotope myocardial perfusion SPECT.

PubMed

Ghaly, Michael; Links, Jonathan M; Frey, Eric C

2015-07-07

Dual-isotope simultaneous-acquisition (DISA) rest-stress myocardial perfusion SPECT (MPS) protocols offer a number of advantages over separate acquisition. However, crosstalk contamination due to scatter in the patient and interactions in the collimator degrade image quality. Compensation can reduce the effects of crosstalk, but does not entirely eliminate image degradations. Optimizing acquisition parameters could further reduce the impact of crosstalk. In this paper we investigate the optimization of the rest Tl-201 energy window width and relative injected activities using the ideal observer (IO), a realistic digital phantom population and Monte Carlo (MC) simulated Tc-99m and Tl-201 projections as a means to improve image quality. We compared performance on a perfusion defect detection task for Tl-201 acquisition energy window widths varying from 4 to 40 keV centered at 72 keV for a camera with a 9% energy resolution. We also investigated 7 different relative injected activities, defined as the ratio of Tc-99m and Tl-201 activities, while keeping the total effective dose constant at 13.5 mSv. For each energy window and relative injected activity, we computed the IO test statistics using a Markov chain Monte Carlo (MCMC) method for an ensemble of 1,620 triplets of fixed and reversible defect-present, and defect-absent noisy images modeling realistic background variations. The volume under the 3-class receiver operating characteristic (ROC) surface (VUS) was estimated and served as the figure of merit. For simultaneous acquisition, the IO suggested that relative Tc-to-Tl injected activity ratios of 2.6-5 and acquisition energy window widths of 16-22% were optimal. For separate acquisition, we observed a broad range of optimal relative injected activities from 2.6 to 12.1 and acquisition energy window of widths 16-22%. A negative correlation between Tl-201 injected activity and the width of the Tl-201 energy window was observed in these ranges. The results also suggested that DISA methods could potentially provide image quality as good as that obtained with separate acquisition protocols. We compared observer performance for the optimized protocols and the current clinical protocol using separate acquisition. The current clinical protocols provided better performance at a cost of injecting the patient with approximately double the injected activity of Tc-99m and Tl-201, resulting in substantially increased radiation dose.

GRAVIMETRIC DETERMINATION OF PLATINIUM, PALLADIUM, RUTHENIUM, RHODIUM AS TlPtS$sub 3$, TlPd$sub 2$S$sub 3$, TlRu$sub 2$S$sub 6$, TlRh$sub 2$S$sub 4$ (in Russian)

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

Rudnev, N.A.; Malofeeva, G.I.

1963-07-01

Gravimetric methods were developed for the determination of microamounts of Ru, Rh, Pt, and Pd as TlRu/sub 2/S/sub 6/, TlRh/sub 2/S/sub 4/ TlPtS/sub 3/, and TlPd/sub 2/S/sub 3/. The methods are simpl e, rapid, and satisfactorily accurate. (auth)

Telomere Length as a Predictor of Aggressive Prostate Cancer

DTIC Science & Technology

2008-11-01

prostate cancer, other prostate diseases, and other cancers. Albadine R, Latour M, Toubaji A, Haffner M, Isaacs WB, Platz EA, Meeker AK, Demarzo AM...PMID: 19267370 Lotan TL, Toubaji A, Albadine R, Latour M, Herawi M, Meeker AK, DeMarzo AM, Platz EA, Epstein JI, Netto GJ. TMPRSS2-ERG gene...Wada S, Yoshimura K, Hipkiss EL, Harris TJ, Yen HR, Goldberg MV, Grosso JF, Getnet D, Demarzo AM, Netto GJ, Anders R, Pardoll DM, Drake CG

Relationship between Telomere Length, Genetic Traits and Environmental/Occupational Exposures in Bladder Cancer Risk by Structural Equation Modelling.

PubMed

Pavanello, Sofia; Carta, Angela; Mastrangelo, Giuseppe; Campisi, Manuela; Arici, Cecilia; Porru, Stefano

2017-12-21

Background : Telomere length (TL) maintenance plays an important role in bladder cancer (BC) and prognosis. However the manifold influence of everyday life exposures and genetic traits on leucocyte TL (LTL), is not fully elucidated. Methods : Within the framework of a hospital-based case ( n = 96)/control ( n = 94) study (all Caucasian males), we investigated the extent to which LTL and BC risk were modulated by genetic polymorphisms and environmental and occupational exposures. Data on lifetime smoking, alcohol and coffee drinking, dietary habits and occupational exposures, pointing to aromatic amines (AAs) and polycyclic aromatic hydrocarbons (PAHs) were collected. Structural equation modelling (SEM) analysis appraised this complex relationships. Results : The SEM analysis indicates negative direct links ( p < 0.05) between LTL with age, DNA adducts, alcohol and NAT2, and positive ones with coffee, MPO and XRCC3; and between BC risk ( p < 0.01) with cigarettes, cumulative exposure to AAs and coffee, while are negative with LTL and age. There was evidence of indirect effects ( p < 0.05) on BC risk, probably via LTL reduction, by age and NAT2 (positive link), MPO and XRCC3 (negative link). Our study supports evidence that LTL attrition is a critical event in BC. The new finding that LTL erosion depends on some preventable everyday life exposures genetically modulated, opens new perspectives in BC prevention.

Relationship between Telomere Length, Genetic Traits and Environmental/Occupational Exposures in Bladder Cancer Risk by Structural Equation Modelling

PubMed Central

Pavanello, Sofia; Carta, Angela; Mastrangelo, Giuseppe; Campisi, Manuela; Porru, Stefano

2017-01-01

Background: Telomere length (TL) maintenance plays an important role in bladder cancer (BC) and prognosis. However the manifold influence of everyday life exposures and genetic traits on leucocyte TL (LTL), is not fully elucidated. Methods: Within the framework of a hospital-based case (n = 96)/control (n = 94) study (all Caucasian males), we investigated the extent to which LTL and BC risk were modulated by genetic polymorphisms and environmental and occupational exposures. Data on lifetime smoking, alcohol and coffee drinking, dietary habits and occupational exposures, pointing to aromatic amines (AAs) and polycyclic aromatic hydrocarbons (PAHs) were collected. Structural equation modelling (SEM) analysis appraised this complex relationships. Results: The SEM analysis indicates negative direct links (p < 0.05) between LTL with age, DNA adducts, alcohol and NAT2, and positive ones with coffee, MPO and XRCC3; and between BC risk (p < 0.01) with cigarettes, cumulative exposure to AAs and coffee, while are negative with LTL and age. There was evidence of indirect effects (p < 0.05) on BC risk, probably via LTL reduction, by age and NAT2 (positive link), MPO and XRCC3 (negative link). Conclusions: Our study supports evidence that LTL attrition is a critical event in BC. The new finding that LTL erosion depends on some preventable everyday life exposures genetically modulated, opens new perspectives in BC prevention. PMID:29267235

Morphological integration and pleiotropy in the adaptive body shape of the snail-feeding carabid beetle Damaster blaptoides.

PubMed

Konuma, Junji; Yamamoto, Satoshi; Sota, Teiji

2014-12-01

The snail-feeding carabid beetle Damaster blaptoides exhibits diverse head and thorax morphologies, and these morphotypes are linked with two alternative feeding behaviours. Stout-shaped beetles feed on snails by crushing the shells, whereas slender-shaped beetles consume snails by inserting their heads into the shells. A trade-off exists between these feeding strategies. Because intermediate-shaped beetles are less proficient in these two behaviours, stout-slender morphological divergence occurs between related species feeding on land snails. To examine the genetic basis of these morphotypes, we conducted morphological analyses and quantitative trait locus (QTL) mapping using backcross offspring between the stout and slender subspecies. The morphological analyses showed that the width and length of the beetle body parts were correlated with each other; in particular, the head width (HW) and thorax length (TL) were strongly negatively correlated. QTL mapping showed that QTLs for HW and TL are located in close proximity to one another on the longest linkage group and that they have positive and negative additive genetic effects. Our results suggest that the adaptive phenotypic sets of a wide head and short thorax and a narrow head and long thorax are based on the closeness of these QTLs. Morphological integration between the head and thorax may play an important role in the adaptive divergence of these beetles. © 2014 John Wiley & Sons Ltd.

The effect of addition of PTFE or urea on luminescence response of copper-doped lithium tetraborate

NASA Astrophysics Data System (ADS)

Iskandar, Ferry; Fajri, Annisa; Nuraeni, Nunung; Stavila, Erythrina; Aimon, Akfiny H.; Nuryadin, Bebeh W.

2018-04-01

Lithium tetraborate (Li2B4O7) is a promising material for application in personal dosimetry due to its tissue equivalent properties. The addition of copper as a dopant in Li2B4O7 is known to increase the sensitivity for both photoluminescent (PL) and thermoluminescent (TL) emission. Therefore, in this paper, synthesis of Li2B4O7:Cu is reported. The optimum synthesis condition was achieved using the solution-assisted method, followed by calcination at 700 °C for 2 h. The addition of 0.1 wt% Cu resulted in the highest PL and TL emissions. Further investigation of the influence of polytetrafluoroethylene (PTFE) or urea addition on the luminescence response of Li2B4O7:Cu is described. All samples were characterized by x-ray diffraction (XRD), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometry, photoluminescence spectrofluorophotometer, thermoluminescence reader, scanning electron microscopy (SEM), and energy dispersive x-ray (EDX) spectroscopy. The addition of PTFE decreased the PL emission of the Li2B4O7:Cu but slightly increased its TL emission. Meanwhile, the addition of urea increased the luminescence emission for both PL and TL of the Li2B4O7:Cu.

An alternative method for immediate dose estimation using CaSO4:Dy based TLD badges

NASA Astrophysics Data System (ADS)

Singh, A. K.; Menon, S. N.; Dhabekar, Bhushan; Kadam, Sonal; Chougaonkar, M. P.; Babu, D. A. R.

2014-11-01

CaSO4:Dy based Thermoluminescence dosimeters (TLDs) are being used in country wide personnel monitoring program in India. The TL glow curve of CaSO4:Dy consists of a dosimetric peak at 220 °C and a low temperature peak at 120 °C which is unstable at room temperature. The TL integral counts in CaSO4:Dy reduces by 15% in seven days after irradiation due to the thermal fading of 120 °C TL peak. As the dosimetric procedure involves total integrated counts for dose conversion, the dosimeters are typically read about a week after receiving. However in the event of a suspected over exposure, where urgent processing is expected, this poses limitation. Post irradiation annealing treatment is used in such cases of immediate readout of cards. In this paper we report a new and easier to use technique based on optical bleaching for the urgent processing of TLD cards. Optical bleaching with green LED (∼555 nm photons) of 25,000 lux for one and half hour removes the low temperature TL peak without affecting the dosimetric peak. This method can be used for immediate dose estimation using CaSO4:Dy based TLD badges.

49 CFR Appendix B to Part 221 - Approved Rear End Marking Devices

Code of Federal Regulations, 2011 CFR

2011-10-01

.... 06460. FRA identification Nos. FRA-ATK-TL-3895-1, FRA-ATK-TL-4491-2, FRA-ATK-TL-4491-3, and FRA-ATK-TL...-300-C (steady burn), and FRA-MEC-MCD-300-F (flasher). 3. Manufacturer: American Electronics, Inc., 1..., Milford, Conn. 06460. FRA identification Nos. FRA-ATSF-TL-875-150, FRA-ATSF-TL-875-60, FRA-ATSF-TL-875...

49 CFR Appendix B to Part 221 - Approved Rear End Marking Devices

Code of Federal Regulations, 2013 CFR

2013-10-01

.... 06460. FRA identification Nos. FRA-ATK-TL-3895-1, FRA-ATK-TL-4491-2, FRA-ATK-TL-4491-3, and FRA-ATK-TL...-300-C (steady burn), and FRA-MEC-MCD-300-F (flasher). 3. Manufacturer: American Electronics, Inc., 1..., Milford, Conn. 06460. FRA identification Nos. FRA-ATSF-TL-875-150, FRA-ATSF-TL-875-60, FRA-ATSF-TL-875...

49 CFR Appendix B to Part 221 - Approved Rear End Marking Devices

Code of Federal Regulations, 2010 CFR

2010-10-01

.... 06460. FRA identification Nos. FRA-ATK-TL-3895-1, FRA-ATK-TL-4491-2, FRA-ATK-TL-4491-3, and FRA-ATK-TL...-300-C (steady burn), and FRA-MEC-MCD-300-F (flasher). 3. Manufacturer: American Electronics, Inc., 1..., Milford, Conn. 06460. FRA identification Nos. FRA-ATSF-TL-875-150, FRA-ATSF-TL-875-60, FRA-ATSF-TL-875...

49 CFR Appendix B to Part 221 - Approved Rear End Marking Devices

Code of Federal Regulations, 2012 CFR

2012-10-01

.... 06460. FRA identification Nos. FRA-ATK-TL-3895-1, FRA-ATK-TL-4491-2, FRA-ATK-TL-4491-3, and FRA-ATK-TL...-300-C (steady burn), and FRA-MEC-MCD-300-F (flasher). 3. Manufacturer: American Electronics, Inc., 1..., Milford, Conn. 06460. FRA identification Nos. FRA-ATSF-TL-875-150, FRA-ATSF-TL-875-60, FRA-ATSF-TL-875...

49 CFR Appendix B to Part 221 - Approved Rear End Marking Devices

Code of Federal Regulations, 2014 CFR

2014-10-01

.... 06460. FRA identification Nos. FRA-ATK-TL-3895-1, FRA-ATK-TL-4491-2, FRA-ATK-TL-4491-3, and FRA-ATK-TL...-300-C (steady burn), and FRA-MEC-MCD-300-F (flasher). 3. Manufacturer: American Electronics, Inc., 1..., Milford, Conn. 06460. FRA identification Nos. FRA-ATSF-TL-875-150, FRA-ATSF-TL-875-60, FRA-ATSF-TL-875...

Performance of Linear and Nonlinear Two-Leaf Light Use Efficiency Models at Different Temporal Scales

DOE PAGES

Wu, Xiaocui; Ju, Weimin; Zhou, Yanlian; ...

2015-02-25

The reliable simulation of gross primary productivity (GPP) at various spatial and temporal scales is of significance to quantifying the net exchange of carbon between terrestrial ecosystems and the atmosphere. This study aimed to verify the ability of a nonlinear two-leaf model (TL-LUEn), a linear two-leaf model (TL-LUE), and a big-leaf light use efficiency model (MOD17) to simulate GPP at half-hourly, daily and 8-day scales using GPP derived from 58 eddy-covariance flux sites in Asia, Europe and North America as benchmarks. Model evaluation showed that the overall performance of TL-LUEn was slightly but not significantly better than TL-LUE at half-hourlymore » and daily scale, while the overall performance of both TL-LUEn and TL-LUE were significantly better (p < 0.0001) than MOD17 at the two temporal scales. The improvement of TL-LUEn over TL-LUE was relatively small in comparison with the improvement of TL-LUE over MOD17. However, the differences between TL-LUEn and MOD17, and TL-LUE and MOD17 became less distinct at the 8-day scale. As for different vegetation types, TL-LUEn and TL-LUE performed better than MOD17 for all vegetation types except crops at the half-hourly scale. At the daily and 8-day scales, both TL-LUEn and TL-LUE outperformed MOD17 for forests. However, TL-LUEn had a mixed performance for the three non-forest types while TL-LUE outperformed MOD17 slightly for all these non-forest types at daily and 8-day scales. The better performance of TL-LUEn and TL-LUE for forests was mainly achieved by the correction of the underestimation/overestimation of GPP simulated by MOD17 under low/high solar radiation and sky clearness conditions. TL-LUEn is more applicable at individual sites at the half-hourly scale while TL-LUE could be regionally used at half-hourly, daily and 8-day scales. MOD17 is also an applicable option regionally at the 8-day scale.« less

Performance of Linear and Nonlinear Two-Leaf Light Use Efficiency Models at Different Temporal Scales

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

Wu, Xiaocui; Ju, Weimin; Zhou, Yanlian

The reliable simulation of gross primary productivity (GPP) at various spatial and temporal scales is of significance to quantifying the net exchange of carbon between terrestrial ecosystems and the atmosphere. This study aimed to verify the ability of a nonlinear two-leaf model (TL-LUEn), a linear two-leaf model (TL-LUE), and a big-leaf light use efficiency model (MOD17) to simulate GPP at half-hourly, daily and 8-day scales using GPP derived from 58 eddy-covariance flux sites in Asia, Europe and North America as benchmarks. Model evaluation showed that the overall performance of TL-LUEn was slightly but not significantly better than TL-LUE at half-hourlymore » and daily scale, while the overall performance of both TL-LUEn and TL-LUE were significantly better (p < 0.0001) than MOD17 at the two temporal scales. The improvement of TL-LUEn over TL-LUE was relatively small in comparison with the improvement of TL-LUE over MOD17. However, the differences between TL-LUEn and MOD17, and TL-LUE and MOD17 became less distinct at the 8-day scale. As for different vegetation types, TL-LUEn and TL-LUE performed better than MOD17 for all vegetation types except crops at the half-hourly scale. At the daily and 8-day scales, both TL-LUEn and TL-LUE outperformed MOD17 for forests. However, TL-LUEn had a mixed performance for the three non-forest types while TL-LUE outperformed MOD17 slightly for all these non-forest types at daily and 8-day scales. The better performance of TL-LUEn and TL-LUE for forests was mainly achieved by the correction of the underestimation/overestimation of GPP simulated by MOD17 under low/high solar radiation and sky clearness conditions. TL-LUEn is more applicable at individual sites at the half-hourly scale while TL-LUE could be regionally used at half-hourly, daily and 8-day scales. MOD17 is also an applicable option regionally at the 8-day scale.« less

Tl(I) and Tl(III) activate both mitochondrial and extrinsic pathways of apoptosis in rat pheochromocytoma (PC12) cells

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

Hanzel, Cecilia Eliana; Verstraeten, Sandra Viviana

2009-04-01

Thallium (Tl) is a highly toxic metal though yet its mechanisms are poorly understood. Previously, we demonstrated that rat pheochromocytoma (PC12) cells exposure to thallous (Tl(I)) or thallic (Tl(III)) cations leads to mitochondrial damage and reduced cell viability. In the present work we comparatively characterized the possible pathways involved in Tl(I)- and Tl(III)- (10-100 {mu}M) mediated decrease in PC12 cells viability. We observed that these cations do not cause cell necrosis but significantly increased the number of cells with apoptotic features. Both cations lead to Bax oligomerization and caused apoptosis inducing factor (AIF), endonuclease G (Endo G), and cytochrome cmore » release from mitochondria, but they did not activate caspase dependent DNAse (CAD). Tl(I)- and Tl(III)-dependent caspases 9 and 3 activation followed similar kinetics, with maximal effects at 18 h of incubation. In addition, Tl(I) promoted phosphatidylserine (PS) exposure. Tl(III) induced 2- and 18-fold increase in Fas content and caspase 8 activity, respectively. Together, experimental results show that Tl(I) and Tl(III) induce PC12 cells apoptosis, although differential pathways are involved. While Tl(I)-mediated cell apoptosis was mainly associated with mitochondrial damage, Tl(III) showed a mixed effect triggering both the intrinsic and extrinsic pathways of apoptosis. These findings contribute to a better understanding of the mechanisms underlying Tl-induced loss of cell viability in PC12 cells.« less

Electronic Structure of Tl2Ba2CuO(6+Delta) Epitaxial Films Measured by X-Ray Photoemission

NASA Technical Reports Server (NTRS)

Vasquez, R. P.; Ren, Z. F.; Wang, J. H.

1996-01-01

The valence electronic structure and core levels of Tl2Ba2CuO(6 + delta) (Tl-2201) epitaxial films have been measured with X-ray photoelectron spectroscopy and are compared to those of Tl2Ba2CaCu2O(8 + delta) (Tl-2212). Changes in the Tl-2201 core-level binding energies with oxygen doping are consistent with a change in the chemical potential. Differences between the Tl-2201 and Tl-2212 measured densities of states are consistent with the calculated Cu 3d and Tl 6s partial densities of states.

Synthesis and characterization of CaF2:Dy nanophosphor for dosimetric application

NASA Astrophysics Data System (ADS)

Bhadane, Mahesh S.; Patil, B. J.; Dahiwale, S. S.; Kulkarni, M. S.; Bhatt, B. C.; Bhoraskar, V. N.; Dhole, S. D.

2015-06-01

In this work, nanoparticles (NPs) of dysprosium doped calcium fluoride (CaF2:Dy) 1 mol % has been prepared using simple chemical co-precipitation method and its thermoluminescence (TL) dosimetric properties were studied. The synthesized nanoparticle sample was characterized by X-ray diffraction (XRD) and the particle size of face centered cubic phase NPs was found around 30 nm. The shape, morphology and size were also observed by scanning electron microscopy (SEM). From gamma irradiated CaF2:Dy TL curves, it was observed that the total areas of all the glow peak intensities are dramatically changed with increase in annealing temperature. Further, TL glow curve of the CaF2:Dy at 183 °C annealed at 400 °C, showed very sharp linear response in the dose range from 1 Gy to 750 Gy. This linear response of CaF2:Dy nanophosphor as a function of gamma dose is very useful from radiation dosimetric point of view.

Microcolumn-based speciation analysis of thallium in soil and green cabbage.

PubMed

Jia, Yanlong; Xiao, Tangfu; Sun, Jialong; Yang, Fei; Baveye, Philippe C

2018-07-15

Thallium (Tl) is a toxic trace metal, whose geochemical behavior and biological effects are closely controlled by its chemical speciation in the environment. However, little tends to be known about this speciation of Tl in soil and plant systems that directly affect the safety of food supplies. In this context, the objective of the present study was to elaborate an efficient method to separate and detect Tl(I) and Tl(III) species for soil and plant samples. This method involves the selective adsorption of Tl(I) on microcolumns filled with immobilized oxine, in the presence of DTPA (diethylenetriaminepentaacetic acid), followed by DTPA-enhanced ultrasonic and heating-induced extraction, coupled with ICP-MS detection. The method was characterized by a LOD of 0.037 μg/L for Tl(I) and 0.18 μg/L for Tl(III) in 10  mL samples. With this method, a second objective of the research was to assess the speciation of Tl in pot and field soils and in green cabbage crops. Experimental results suggest that DTPA extracted Tl was mainly present as Tl(I) in soils (>95%). Tl in hyperaccumulator plant green cabbage was also mainly present as Tl(I) (>90%). With respect to Tl uptake in plants, this study provides direct evidence that green cabbage mainly takes up Tl(I) from soil, and transports it into the aboveground organs. In soils, Tl(III) is reduced to Tl(I) even at the surface where the chemical environment promotes oxidation. This observation is conducive to understanding the mechanisms of Tl isotope fractionation in the soil-plant system. Based on geochemical fraction studies, the reducible fraction was the main source of Tl getting accumulated by plants. These results indicate that the improved analytical method presented in this study offers an economical, simple, fast, and sensitive approach for the separation of Tl species present in soils at trace levels. Copyright © 2018 Elsevier B.V. All rights reserved.

Cenozoic marine geochemistry of thallium deduced from isotopic studies of ferromanganese crusts and pelagic sediments

USGS Publications Warehouse

Rehkamper, M.; Frank, M.; Hein, J.R.; Halliday, A.

2004-01-01

Cenozoic records of Tl isotope compositions recorded by ferromanganese (Fe-Mn) crusts have been obtained. Such records are of interest because recent growth surfaces of Fe-Mn crusts display a nearly constant Tl isotope fractionation relative to seawater. The time-series data are complemented by results for bulk samples and leachates of various marine sediments. Oxic pelagic sediments and anoxic marine deposits can be distinguished by their Tl isotope compositions. Both pelagic clays and biogenic oozes are typically characterized by ??205Tl greater than +2.5, whereas anoxic sediments have ??205Tl of less than -1.5 (??205Tl is the deviation of the 205Tl/203Tl isotope ratio of a sample from NIST SRM 997 Tl in parts per 104). Leaching experiments indicate that the high ??205Tl values of oxic sediments probably reflect authigenic Fe-Mn oxyhydroxides. Time-resolved Tl isotope compositions were obtained from six Fe-Mn crusts from the Atlantic, Indian, and Pacific oceans and a number of observations indicate that these records were not biased by diagenetic alteration. Over the last 25 Myr, the data do not show isotopic variations that significantly exceed the range of Tl isotope compositions observed for surface layers of Fe-Mn crusts distributed globally (??205 Tl=+12.8??1.2). This indicates that variations in deep-ocean temperature were not recorded by Tl isotopes. The results most likely reflect a constant Tl isotope composition for seawater. The growth layers of three Fe-Mn crusts that are older than 25 Ma show a systematic increase of ??205Tl with decreasing age, from about +6 at 60-50 Ma to about +12 at 25 Ma. These trends are thought to be due to variations in the Tl isotope composition of seawater, which requires that the oceans of the early Cenozoic either had smaller output fluxes or received larger input fluxes of Tl with low ??205Tl. Larger inputs of isotopically light Tl may have been supplied by benthic fluxes from reducing sediments, rivers, and/or volcanic emanations. Alternatively, the Tl isotope trends may reflect the increasing importance of Tl fluxes to altered ocean crust through time. ?? 2004 Elsevier B.V. All rights reserved.

Investigation of thallium fluxes from subaerial volcanism-Implications for the present and past mass balance of thallium in the oceans

USGS Publications Warehouse

Baker, R.G.A.; Rehkamper, M.; Hinkley, T.K.; Nielsen, S.G.; Toutain, J.P.

2009-01-01

A suite of 34 volcanic gas condensates and particulates from Kilauea (Hawaii), Mt. Etna and Vulcano (Italy), Mt. Merapi (Indonesia), White Island and Mt. Nguaruhoe (New Zealand) were analysed for both Tl isotope compositions and Tl/Pb ratios. When considered together with published Tl-Pb abundance data, the measurements provide globally representative best estimates of Tl/Pb = 0.46 ?? 0.25 and ??205Tl = -1.7 ?? 2.0 for the emissions of subaerial volcanism to the atmosphere and oceans (??205Tl is the deviation of the 205Tl/203Tl isotope ratio from NIST SRM 997 isotope standard in parts per 10,000). Compared to igneous rocks of the crust and mantle, volcanic gases were found to have (i) Tl/Pb ratios that are typically about an order of magnitude higher, and (ii) significantly more variable Tl isotope compositions but a mean ??205Tl value that is indistinguishable from estimates for the Earth's mantle and continental crust. The first observation can be explained by the more volatile nature of Tl compared to Pb during the production of volcanic gases, whilst the second reflects the contrasting and approximately balanced isotope fractionation effects that are generated by partial evaporation of Tl during magma degassing and partial Tl condensation as a result of the cooling and differentiation of volcanic gases. Mass balance calculations, based on results from this and other recent Tl isotope studies, were carried out to investigate whether temporal changes in the volcanic Tl fluxes could be responsible for the dramatic shift in the ??205Tl value of the oceans at ???55 Ma, which has been inferred from Tl isotope time series data for ferromanganese crusts. The calculations demonstrate that even large changes in the marine Tl input fluxes from volcanism and other sources are unable to significantly alter the Tl isotope composition of the oceans. Based on modelling, it is shown that the large inferred change in the ??205Tl value of seawater is best explained if the oceans of the early Cenozoic featured significantly larger Tl output fluxes to oxic pelagic sediments, whilst the sink fluxes to altered ocean crust remained approximately constant. ?? 2009 Elsevier Ltd.

Matrix Metalloproteinase Expression in the Rat Myometrium During Pregnancy, Term Labor, and Postpartum1

PubMed Central

Nguyen, Tina Tu-Thu Ngoc; Shynlova, Oksana; Lye, Stephen J.

2016-01-01

Pregnancy, spontaneous term labor (TL), and postpartum (PP) involution are associated with changes in the cellular and extracellular matrix composition of the uterus. Both the uterine smooth muscle (myometrium) and the infiltrating peripheral blood leukocytes involved in the activation of labor secrete extracellular matrix-degrading enzymes (matrix metalloproteinases, MMPs) that can modulate cellular behavior and barrier function. MMP expression is induced by mechanical stretch in several tissues. We hypothesized that the expression and activity of myometrial MMPs and their tissue inhibitors (TIMPs) are modulated in preparation for TL and PP involution and are regulated by mechanical stretch of uterine walls imposed by the growing fetus. Myometrial tissues were collected from bilaterally and unilaterally pregnant rats across gestation, TL, and PP. Total RNA and proteins were subjected to real-time PCR and immunoblotting, respectively, and tissue localization and activity was examined by immunohistochemistry and in situ zymography. We found that Mmp7, Mmp11, and Mmp12 mRNA levels were upregulated during TL and PP, while Mmp2, Mmp3, Mmp8, Mmp9, Mmp10, and Mmp13 mRNAs were only upregulated during PP. Timp1–Timp4 were stably expressed throughout gestation with some fluctuations PP. Active MMP2 was induced in the empty uterine horn during gestation and in the gravid PP uterus, suggesting negative regulation by biological mechanical stretch. We conclude that specific subsets of uterine MMPs are differentially regulated in the rat myometrium in preparation for two major events: TL and PP uterine involution. PMID:27251092

Distribution of chemical elements in soils and stream sediments in the area of abandoned Sb-As-Tl Allchar mine, Republic of Macedonia.

PubMed

Bačeva, Katerina; Stafilov, Trajče; Šajn, Robert; Tănăselia, Claudiu; Makreski, Petre

2014-08-01

The aim of this study was to investigate the distribution of some toxic elements in topsoil and subsoil, focusing on the identification of natural and anthropogenic element sources in the small region of rare As-Sb-Tl mineralization outcrop and abandoned mine Allchar known for the highest natural concentration of Tl in soil worldwide. The samples of soil and sediments after total digestion were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Factor analysis (FA) was used to identify and characterize element associations. Six associations of elements were determined by the method of multivariate statistics: Rb-Ta-K-Nb-Ga-Sn-Ba-Bi-Li-Be-(La-Eu)-Hf-Zr-Zn-In-Pd-Ag-Pt-Mg; Tl-As-Sb-Hg; Te-S-Ag-Pt-Al-Sc-(Gd-Lu)-Y; Fe-Cu-V-Ge-Co-In; Pd-Zr-Hf-W-Be and Ni-Mn-Co-Cr-Mg. The purpose of the assessment was to determine the nature and extent of potential contamination as well as to broadly assess possible impacts to human health and the environment. The results from the analysis of the collected samples in the vicinity of the mine revealed that As and Tl elements have the highest median values. Higher median values for Sb are obviously as a result of the past mining activities and as a result of area surface phenomena in the past. Copyright © 2014 Elsevier Inc. All rights reserved.

Isoantigens of the H-2 and Tla loci of the mouse: interactions affecting their representation on thymocytes.

PubMed

Boyse, E A; Stockert, E; Old, L J

1968-07-01

H-2 and TL isoantigens of the mouse are specified by the closely linked genetic loci H-2 and Tla. A. study of their representation on thymocytes was performed in order to reveal any interactions between the determinant genes or their products affecting the synthesis or disposition of these components of the thymocyte surface. The method employed was quantitative absorption of cytotoxic antibody by viable thymocytes. The phenotypic expression of TL antigens was found to reduce the demonstrable amount of certain H-2 antigens to as little as 34% of the quantity demonstrable on TL- thymocytes. A reduction was observed in all three H-2 types tested, (H-2(b), H-2(a), and H-2(k)). As antigenic modulation (change of TL phenotype from TL+ to TL-, produced by TL antibody) is known to entail a compensatory increase in H-2(D) antigen, it is concluded that the TL phenotype, rather than the Tla genotype, influences the surface representation of H-2 antigens. The two known TL+ phenotypes of thymocytes (TL.2 and TL.1,2,3) depress H-2 equally. The H-2 specificities affected are those determined by the D end of the E-2 locus, which is adjacent to Tla; antigens of the K end, which is distal to Tla, are not depressed. The reduction of demonstrable H-2 antigen on the thymocytes of TL+ x TL- progeny is half that of thymocytes of TL+ x TL+ progeny and the reduction affects equally the products of both H-2 alleles (cis and trans in relation to Tla), indicating that the mechanism of H-2 reduction by TL is extrachromosomal. Whether it involves diminished synthesis of H-2 or steric masking by TL at the cell membrane is unknown, but in either case the reciprocal relation of TL and H-2(D) antigens implies that they probably occupy adjacent positions on thymocytes and that the gene order, H-2(K): H-2(D):Tla is reflected in cell surface structure. Extrachromosomal interaction, apparently involving control of synthesis, occurs also within the TL system of antigens. Thymocytes of TL.2 x TL.1,2,3 progeny express the full homozygous quantity of antigens TL.1 and TL.3 (but not of TL.2), in contrast to the half-quantity present in thymocytes of TL- x TL.1,2,3 progeny. Another example of interaction is implicit in the finding that thymocytes of TL-1,2,3 x TL.1,2,3 progeny have more TL.2 antigen than thymocytes of TL.2 x TL.2 progeny, but in this instance there is nothing to indicate whether the mechanism is chromosomal or extrachromosomal. Thus the quantitative surface representation of at least some H-2 and TL antigens is influenced by the cellular complement of H-2:Tla genes as a whole. Comparison of H-2 heterozygous thymocytes with H-2 homozygous thymocytes in quantitative absorption tests shows (a) more than the expected 50% of each parental-type H-2 antigen on heterozygous cells, and (b) a greater suppression of H-2 by TL in H-2 heterozygotes in comparison with H-2 homozygotes. Both results may be explained on the basis of differences in the density of H-2 antigenic sites and consequent differences in the efficiency of absorption of H-2 antibody. These considerations may be useful in other contexts, e.g. in estimating the representation of Rh antigens on the red cells of human subjects homozygous and heterozygous for Rh components.

ANTIGENIC MODULATION

PubMed Central

Old, Lloyd J.; Stockert, Elisabeth; Boyse, Edward A.; Kim, Jae Ho

1968-01-01

Antigenic modulation (the loss of TL antigens from TL+ cells exposed to TL antibody in the absence of lytic complement) has been demonstrated in vitro. An ascites leukemia, phenotype TL.1,2,3, which modulates rapidly and completely when incubated with TL antiserum in vitro, was selected for further study of the phenomenon. Over a wide range of TL antibody concentrations modulation at 37°C was detectable within 10 min and was complete within approximately 1 hr. The cells were initially sensitized to C' by their contact with antibody, thereafter losing this sensitivity to C' lysis together with their sensitivity to TL antibody and C' in the cytotoxic test. The capacity of the cells to undergo modulation was abolished by actinomycin D and by iodoacetamide, and by reducing the temperature of incubation to 0°C. Thus modulation apparently is an active cellular process. Antigens TL. 1,2, and 3 are all modulated by anti-TL.1,3 serum and by anti-TL.3 serum. This modulation affects all three TL components together, even when antibody to one or two of them is lacking. aAnti-TL.2 serum does not induce modulation and in fact impairs modulation by the other TL antibodies. The influence of the TL phenotype of cells upon the demonstrable content of H-2 (D region) isoantigen, first shown in cells modulated in vivo, has been observed with cells modulated in vitro. Cells undergoing modulation show a progressive increase in H-2 (D region) antigen over a period of 4 hr, with no change in H-2 antigens of the K region. Restoration of the TL+ phenotype of modulated cells after removal of antibody is less rapid than TL+ → TL- modulation and may require several cell divisions. PMID:5636556

Thermoluminescence characteristics of Ge-doped optical fibers with different dimensions for radiation dosimetry.

PubMed

Begum, Mahfuza; Rahman, A K M Mizanur; Abdul-Rashid, H A; Yusoff, Z; Begum, Mahbuba; Mat-Sharif, K A; Amin, Y M; Bradley, D A

2015-06-01

Important thermoluminescence (TL) properties of five (5) different core sizes Ge-doped optical fibers have been studied to develop new TL material with better response. These are drawn from same preform applying different speed and tension during drawing phase to produce Ge-doped optical fibers with five (5) different core sizes. The results of the investigations are also compared with most commonly used standard TLD-100 chips (LiF:Mg,Ti) and commercial multimode Ge-doped optical fiber (Yangtze Optical Fiber, China). Scanning Electron Microscope (SEM) and EDX analysis of the fibers are also performed to map Ge distribution across the deposited region. Standard Gamma radiation source in Secondary Standard Dosimetry Lab (SSDL) was used for irradiation covering dose range from 1Gy to 10Gy. The essential dosimetric parameters that have been studied are TL linearity, reproducibility and fading. Prior to irradiation all samples ∼0.5cm length are annealed at temperature of 400°C for 1h period to standardize their sensitivities and background. Standard TLD-100 chips are also annealed for 1h at 400°C and subsequently 2h at 100°C to yield the highest sensitivity. TL responses of these fibers show linearity over a wide gamma radiation dose that is an important property for radiation dosimetry. Among all fibers used in this study, 100μm core diameter fiber provides highest response that is 2.6 times than that of smallest core (20μm core) optical fiber. These fiber-samples demonstrate better response than commercial multi-mode optical fiber and also provide low degree of fading about 20% over a period of fifteen days for gamma radiation. Effective atomic number (Zeff) is found in the range (13.25-13.69) which is higher than soft tissue (7.5) however within the range of human-bone (11.6-13.8). All the fibers can also be re-used several times as a detector after annealing. TL properties of the Ge-doped optical fibers indicate promising applications in ionizing radiation dosimetry. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structural and elastic properties of AIBIIIC 2 VI semiconductors

NASA Astrophysics Data System (ADS)

Kumar, V.; Singh, Bhanu P.

2018-01-01

The plane wave pseudo-potential method within density functional theory has been used to calculate the structural and elastic properties of AIBIIIC 2 VI semiconductors. The electronic band structure, density of states, lattice constants (a and c), internal parameter (u), tetragonal distortion (η), energy gap (Eg), and bond lengths of the A-C (dAC) and B-C (dBC) bonds in AIBIIIC 2 VI semiconductors have been calculated. The values of elastic constants (Cij), bulk modulus (B), shear modulus (G), Young's modulus (Y), Poisson's ratio (υ), Zener anisotropy factor (A), Debye temperature (ϴD) and G/B ratio have also been calculated. The values of all 15 parameters of CuTlS2 and CuTlSe2 compounds, and 8 parameters of 20 compounds of AIBIIIC 2 VI family, except AgInS2 and AgInSe2, have been calculated for the first time. Reasonably good agreement has been obtained between the calculated, reported and available experimental values.

Synthesis and in vivo evaluation of 201Tl(III)-DOTA complexes for applications in SPECT imaging.

PubMed

Hijnen, Nicole M; de Vries, Anke; Blange, Roy; Burdinski, Dirk; Grüll, Holger

2011-05-01

The aim of this study was to assess the use of (201)thallium(3+) ((201)Tl(3+)) as a radiolabel for nuclear imaging tracers. Methods for labeling of 1,4,7,10-tetraazacyclododecane-N,N',N″,N'″ tetraacetic acid (DOTA) and diethylenetriaminepentaacetic acid (DTPA) chelators with (201)Tl(3+) were investigated, and the levels of stability of these chelates were tested in vitro and in vivo. (201)Tl(I)Cl was treated with hydrochloric acid and ozone to form (201)Tl(III)Cl(3). The procedure for labeling of DOTA and DTPA was optimized, testing different buffer solutions and pH values. The stability levels of (201)Tl(III)-DOTA and (201)Tl(III)-DTPA were assessed in buffer, mouse serum and human serum (1:1, v/v) at a temperature of 310 K for 48 h. Subsequently, in vivo stability studies with (201)Tl(III)-DOTA were performed, comparing the biodistribution of (201)Tl(III)-DOTA with that of (201)Tl(I)Cl in a single-isotope study and with that of (177)Lu(III)-DOTA in a dual-isotope single photon emission computed tomography study. (201)Tl(III)-DTPA, (201)Tl(III)-DOTA and (177)Lu(III)-DOTA were prepared with >95% radiochemical purity. While (201)Tl(III)-DOTA showed a prolonged level of stability in buffer and serum, (201)Tl was quickly released from DTPA in serum. Apart from some urinary excretion, the biodistribution of DOTA-chelated (201)Tl(3+) was similar to that of free (ionic) (201)Tl(+) and did not match the biodistribution of (177)Lu(III)-DOTA. This indicated a limited stability of (201)Tl(III)-DOTA complexes in vivo. Despite promising results on the labeling and in vitro stability of (201)Tl(III)-DOTA, our in vivo results indicate that the integrity of (201)Tl(III)-DOTA decreases to <20% during the time required for urinary excretion, thereby limiting the use of (201)Tl(3+) as a radiolabel for tracer imaging. Copyright © 2011 Elsevier Inc. All rights reserved.

THEORY AND MEASUREMENT OF VISUAL MECHANISMS

PubMed Central

Crozier, W. J.; Wolf, Ernst

1941-01-01

For spectral regions associated with violet, blue, green, and red the relation between mean critical flash intensity Im for visual flicker and the flash frequency F is modified as already found with white light when the light time fraction tL in the flash cycle is changed. For a square image 6.13° on a side, foveally fixated, the "rod" and "cone" contributions to the duplex contour are analyzed in the way already used for white. It is pointed out that several customary qualitative criteria for cone functioning do not necessarily give concordant results. The analysis shows that the three parameters of the probability summations giving the "rod" and "cone" curves are changed independently as a function of wave-length composition of the light, and of the light time fraction. The correlation of these changes, and of those found in the associated variability functions, can be understood in terms of differences in (1) the numbers of neural units potentially excitable and (2) in the numbers of elements of neural effect obtained from them. In a multivariate situation of this kind it is necessary to compare intensities of luminous flux required to activate half the total population of potentially available elements when this total size is held constant for the different conditions. The results of this comparison, for the filtered lights used, are discussed in relation to certain aspects of excitation vs. wave-length. The problem is a general one, arising where the effects produced as a function of a particular variable are concerned. In the distinction between (1) units excited and (2) the actions they produce may be found the clue for the curious fact that with certain wave-lengths the critical intensities are lower than for white. The extension of the observations to other parts of the retina may be expected to further this analysis. PMID:19873261

50 CFR 622.185 - Size limits.

Code of Federal Regulations, 2013 CFR

2013-10-01

...), TL. (3) Blackfin, cubera, dog, gray, mahogany, queen, silk, and yellowtail snappers—12 inches (30.5 cm), TL. (4) Mutton snapper—16 inches (40.6 cm), TL. (5) Lane snapper—8 inches (20.3 cm), TL. (b...), TL. (2) Gray triggerfish in the South Atlantic EEZ off Florida—12 inches (30.5 cm), TL. (3) Hogfish...

50 CFR 622.185 - Size limits.

Code of Federal Regulations, 2014 CFR

2014-10-01

...), TL. (3) Blackfin, cubera, dog, gray, mahogany, queen, silk, and yellowtail snappers—12 inches (30.5 cm), TL. (4) Mutton snapper—16 inches (40.6 cm), TL. (5) Lane snapper—8 inches (20.3 cm), TL. (b...), TL. (2) Gray triggerfish in the South Atlantic EEZ off Florida—12 inches (30.5 cm), TL. (3) Hogfish...

Outcomes following total laryngectomy for squamous cell carcinoma: one centre experience.

PubMed

Leong, S C; Kartha, S-S; Kathan, C; Sharp, J; Mortimore, S

2012-12-01

To evaluate the clinical outcomes of total laryngectomy (TL), complications and factors affecting survival. Retrospective review of hospital electronic database for head and neck squamous cell carcinoma (SCCa). Large district general hospital in England, United Kingdom. Patients who had TL between January 1994 and January 2008. 5-year disease specific survival (DSS) and disease-free survival (DFS). Seventy-one patients were reviewed, of whom 38 (54%) had laryngeal SCCa and 33 (46%) hypopharyngeal SCCa. The overall mean survival period following TL was 42.4 months. The 5-year DSS and DFS was better for laryngeal SCCa compared to hypopharyngeal SCCa, although not statistically significant (P=0.090, P=0.54 respectively). Patients treated for laryngeal SCCa had a mean survival period of 47.5 months compared to 36.5 months for hypopharyngeal disease. Those who had laryngeal recurrence after primary radiotherapy (RT) demonstrated statistically better survival probability than those who had hypopharyngeal recurrence (P=0.011). Patients without cervical lymphadenopathy had statistically better survival (P=0.049). The most common early complication was related to the cardiorespiratory system. One fatal complication of erosion of the brachiocephalic artery due to the laryngectomy tube was noted. The most common late complication was neopharyngeal stenosis. The commonest cause of death was due to locoregional recurrence, followed by medical co-morbidities. Patients referred to specialised head and neck clinic had a better survival probability than those referred to a general ENT clinic (P=0.37). While there is increasing tendency towards laryngeal conservation, total laryngectomy remains a robust treatment option in selected patients. Copyright © 2012. Published by Elsevier Masson SAS.

Influence of thermally oxidized vegetable oils and animal fats on energy and nutrient digestibility in young pigs.

PubMed

Liu, P; Kerr, B J; Chen, C; Weber, T E; Johnston, L J; Shurson, G C

2014-07-01

A total of 108 barrows (6.67 ± 0.03 kg BW) were assigned to 12 dietary treatments in a 4 × 3 factorial design plus a corn-soybean meal control diet to evaluate the effect of lipid source and peroxidation level on DE, ME, and apparent total tract digestibility (ATTD) of DM, GE, ether extract (EE), N, and C in young pigs. Main effects were lipid source (corn oil [CN], canola oil [CA], poultry fat [PF], and tallow [TL]) and peroxidation level (original lipids [OL], slow oxidation [SO] of lipids heated for 72 h at 95°C, or rapid oxidation [RO] of lipids heated for 7 h at 185°C). Pigs were provided ad libitum access to diets for 28 d followed by an 8-d period of controlled feed intake equivalent to 4% BW daily. Diets were formulated based on the ME content of CA with the standardized ileal digestible Lys, Met, Thr, Trp, total Ca, and available P:ME balanced relative to NRC (1998) recommendations. Lipid peroxidation analysis indicated that compared with the OL, SO and RO had a markedly increased concentrations of lipid peroxidation products, and the increase of peroxidation products in CN and CA were greater than those in PF and TL. Addition of lipids to diets increased (P < 0.05) ATTD of EE and tended to improve (P = 0.06) ATTD of GE compared with pigs fed the control diet. Feeding CN or CA increased (P < 0.05) ATTD of DM, GE, EE, N, and C compared with feeding TL, while feeding PF improved (P < 0.05) ATTD of GE and EE and tended to increase (P = 0.06) ATTD of C compared with TL. Pigs fed CN had increased (P = 0.05) percentage N retention than pigs fed TL. No peroxidation level effect or interaction between lipid source and peroxidation level on DE and ME was observed. Lipid source tended (P = 0.08) to affect DE but not ME values of experimental lipids (P > 0.12). Digestible energy values for CA (8,846, 8,682, and 8,668 kcal/kg) and CN (8,867, 8,648, and 8,725 kcal/kg) were about 450 kcal/kg greater than that of TL (8,316, 8,168, and 8,296 kcal/kg), with PF being intermediate (8,519, 8,274, and 8,511 kcal/kg), for OL, SO, and RO lipids, respectively, respectively. In conclusion, lipid source affected ATTD of dietary DM, GE, EE, N, and C, and N retention and tended to influence the DE value of the lipid but did not significantly affect their ME value. Rapid and slow heating of lipids used in this study increased lipid peroxidation products but had no detectable effects on nutrient and energy digestibility as well as DE and ME values of the various lipids.

How great white sharks nourish their embryos to a large size: evidence of lipid histotrophy in lamnoid shark reproduction.

PubMed

Sato, Keiichi; Nakamura, Masaru; Tomita, Taketeru; Toda, Minoru; Miyamoto, Kei; Nozu, Ryo

2016-09-15

The great white shark (Carcharodon carcharias) exhibits viviparous and oophagous reproduction. A 4950 mm total length (TL) gravid female accidentally caught by fishermen in the Okinawa Prefecture, Southern Japan carried six embryos (543-624 mm TL, three in each uterus). Both uteri contained copious amounts of yellowish viscous uterine fluid (over 79.2 litres in the left uterus), nutrient eggs and broken egg cases. The embryos had yolk stomachs that had ruptured, the mean volume of which was approximately 197.9 ml. Embryos had about 20 rows of potentially functional teeth in the upper and lower jaws. Periodic acid Schiff (PAS)-positive substances were observed on the surface and in the cytoplasm of the epithelial cells, and large, secretory, OsO4-oxidized lipid droplets of various sizes were distributed on the surface of the villous string epithelium on the uterine wall. Histological examination of the uterine wall showed it to consist of villi, similar to the trophonemata of Dasyatidae rays, suggesting that the large amount of fluid found in the uterus of the white shark was likely required for embryo nutrition. We conclude that: (1) the lipid-rich fluid is secreted from the uterine epithelium only in early gestation before the onset of oophagy, (2) the embryos probably use the abundant uterine fluid and encased nutrient eggs for nutrition at this stage of their development, and (3) the uterine fluid is the major source of embryonic nutrition before oophagy onset. This is the first record of the lipid histotrophy of reproduction among all shark species. © 2016. Published by The Company of Biologists Ltd.

Feeding habits of the bluemouth, Helicolenus dactylopterus dactylopterus (Delaroche, 1809) (Pisces: Sebastidae) in the Portuguese coast

NASA Astrophysics Data System (ADS)

Neves, Ana; Sequeira, Vera; Paiva, Rafaela Barros; Vieira, Ana Rita; Gordo, Leonel Serrano

2012-06-01

In order to investigate the feeding habits of Helicolenus dactylopterus dactylopterus along the continental Portuguese coast, a total of 619 individuals were sampled of which 60% contained food in their stomach and 35% had more than one prey item. Among the 81 prey items that were identified in the stomachs, benthic and benthopelagic prey prevail on this species diet. Acantephyra sp, Pasiphaea sp, mysidacea, and teleostei n.i. were the prey with the higher percent index of relative importance (%IRI) value. Three length groups (5-20 cm, 21-27 cm, and 28-48 cm) were defined through cluster analysis of the mean abundance of prey items. A permutational MANOVA detected significant differences in the diet and stomach fullness index for TLG, season, and maturation stage. Smaller fishes had a generalized diet, feeding mainly on mysidacea changing their diet above 20 cm TL, where a major consumption of natantia was found. The larger individuals, >28 cm TL, present a less generalized diet with pisces as dominant prey group. Seasonally, natantia and pisces were the principal prey groups during spring and winter, respectively, while mysidacea and other crustaceans were predominant during the rest of the year. Mysidacea were also the main prey group for immature individuals while natantia and pisces were the principal prey groups to the other maturity stages. The results of this study indicate that H. d. dactylopterus has a diverse diet focused on small crustaceans such as misyds and as specimens grow shrimps and fishes become more consumed, with larger specimens having a more specialized diet. The different nutritional needs during spawning season also seemed to influence the feeding habits of H. d. dactylopterus.

Relationship between Occupational Stress, 5-HT2A Receptor Polymorphisms and Mental Health in Petroleum Workers in the Xinjiang Arid Desert: A Cross-Sectional Study.

PubMed

Jiang, Ting; Ge, Hua; Sun, Jian; Li, Rong; Han, Rui; Liu, Jiwen

2017-04-10

At present, there is growing interest in research examining the relationship between occupational stress and mental health. Owing to the socioeconomic impact of occupational stress and the unique environment of petroleum workers in Xinjiang, a cross-sectional study was carried out between April and December 2015 to investigate the relationship between occupational stress, 5-hydroxytryptamine receptor (5-HTR2A) genotype, and mental health. A total of 1485 workers were selected. The Symptom Checklist 90 was used to assess nine classes of psychological symptoms. Work-related stressors were evaluated using the Occupational Stress Inventory-Revised Edition. Levels of 5-HTR2A (the Tl02C and A-1438G single nucleotide polymorphism in the 5-HTR2A gene) were measured by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The findings of the present study revealed a high prevalence rate of mental health problems (40.29%) in petroleum workers stationed in the arid desert, and suggested a strong correlation between occupational stress and mental health. The TC and CC genotype of Tl02C were found to be protective factors against mental health problems (odds ratio (OR) = 0.455, 95% confidence interval (CI): = 0.269-0.771, odds ratio (OR) = 0.340, 95% confidence interval (CI): 0.162-0.716). AG and GG genotype of A-1438G [odds ratio (OR) 1 = 2.729, 95% confidence interval (CI): 1.433-5.195; odds ratio (OR) 2 = 2.480, 95% confidence interval (CI): 1.221-5.037] were revealed as risk factors. These data provide evidence that occupational stress and 5-HTR2A gene polymorphism contributes to the incidence of mental health problems.

Plasma steroid hormone profiles and reproductive biology of the epaulette shark, Hemiscyllium ocellatum.

PubMed

Heupel, M R; Whittier, J M; Bennett, M B

1999-10-01

Examination of the reproductive biology of the oviparous epaulette shark, Hemiscyllium ocellatum, was conducted on a wild population. Male sharks were found to reach maturity at between 55-60 cm total length (TL) and female sharks mature around 55 cm TL. Blood samples collected from mature male and female sharks were analyzed for sex steroid hormones to examine seasonal hormone patterns. Plasma samples were analyzed via radioimmunoassay techniques with female samples measured for estradiol, progesterone, and androgen concentrations, and male samples measured for androgen concentrations. Male androgen concentrations showed a single broad peak from July to October with maximum hormone concentrations (60 ng/ml) occurring in August. Male androgen concentrations were lowest in December-February (<20 ng/ml), and appeared to correlate with reproductive activity and water temperature. Female androgen concentrations were an order of magnitude lower than those for males and showed peaks in June (6 ng/ml) and December (8 ng/ml). Estradiol concentrations in females peaked during the months of September-November (0.5 ng/ml) coinciding with the egg laying period. Progesterone concentrations ranged up to 0.5 ng/ml prior to the mating season. Observations of ova size and egg production showed eggs develop in pairs and ova are ovulated at a size of 25-27 mm. Females lay eggs from August to January. Males were observed with swollen claspers from July through December, with the highest amount of sperm storage in the epididymis occurring between August through November. Our observations indicate that epaulette sharks in the waters near Heron Island mate from July through December. J. Exp. Zool. 284:586-594, 1999. Copyright 1999 Wiley-Liss, Inc.

Electronic properties of high-temperature superconductors

NASA Astrophysics Data System (ADS)

Richert, Brent Armand

1989-08-01

A semiempirical tight-binding model was developed for the electronic energy bands, the local and total densities of states, and the atomic valences in the high temperature superconductors La(1.85)Sr(0.15)CuO4, YBaCu307, Bi2Sr2CuO6, Bi2CaSr2Cu2O8, Tl2Ba2CuO6, Tl2CaBa2Cu2O8, Tl2Ca2Ba2Cu3O10, TlCa3Ba2Cu4O11, BaPb(0.75)Bi(0.25)O3, and Ba(0.6)K(0.4)BiO3. Calculations of the changes in electronic properties associated with atomic substitutions in YBa2Cu3O7, Bi2CaSr2Cu2O8, and Tl2CaBa2Cu2O8 give results in agreement with expected chemical trends and consistent with observed changes in the superconducting properties. For example, substitution of Lead for Bismuth in BiMCaSr2Cu2O8 increases the concentration of hole carriers within the CuO2 planes. Similarly, doping with Mercury or Pb in TlMCaBa2Cu2O8 also affects the carrier concentration, with Hg creating holes and Pb destroying them. Oxygen vacancies in both La(1.85)Sr(0.15)CuO(4-y) and YBa2Cu3O(7-y) act as electron donors. This is consistent with the observations that oxygen vacancies degrade the superconductivity and metallic conductivity in these materials. Lanthanum vacancies in La2-xCuO4 donate holes, giving the same electronic effect as doping with divalent metal atoms or excess oxygen initially stoichiometric La2CuO4. A specific excitonic mechanism for high temperature superconductivity is proposed which requires insulating metal oxide layers adjacent to the superconducting planes.

2D Thermoluminescence imaging of dielectric surface long term charge memory of plasma surface interaction in DBD discharges

NASA Astrophysics Data System (ADS)

Ambrico, Paolo F.; Ambrico, Marianna; Schiavulli, Luigi; De Benedictis, Santolo

2014-07-01

The charge trapping effect due to the exposure of alumina surfaces to plasma has been studied in a volume dielectric barrier discharge (DBD) in Ar and He noble gases. The long lasting charge trapping of alumina dielectric plates, used as barriers in DBDs, is evidenced by an ex situ thermoluminescence (TL) experiment performed with a standard and a custom two-dimensional (2D)-TL apparatus. The spatial density of trapped surface charges is found to be strongly correlated to the plasma morphology, and the surface spatial memory lasted for several minutes to hours after plasma exposure. In the case of Ar, the plasma channel impact signature on the surface shows a higher equivalent radiation dose with respect to the surface plasma wave and the post-discharge species signature. As a consequence, for the development of discharges, inside the dielectric surface the availability of lower energy trapped electrons is larger in the first region of plasma impact. The reported spatial memory increases the likelihood of the occurrence of plasma filaments in the same position in different runs. In He plasmas, the dielectric barrier shows an almost uniform distribution of trapped charges, meaning that there is no preferred region for the development of the discharge. In all cases a slight asymmetry was shown in the direction of the gas flow. This can be interpreted as being due to the long-living species moving in the direction of the gas flow, corresponding with the TL side experiment on the sample exposed to the plasma afterglow. The maximum values and the integral of the 2D-TL images showed a linear relation with the total charge per ac cycle, corresponding with findings for the TL glow curve. In conclusion, 2D-TL images allow the retrieval of information regarding the plasma surface interaction such as the plasma morphology, trap sites and their activation temperature.

Soil pollution by oxidation of tailings from toxic spill of a pyrite mine.

PubMed

Simón, M; Martín, F; Ortiz, I; García, I; Fernández, J; Fernández, E; Dorronsoro, C; Aguilar, J

2001-11-12

On the 25th April 1998, toxic water and tailings from a pyrite mine of Aznalcóllar (southern Spain) spilled into the Agrio and Guadiamar River Basin affecting some 40 km2. In five sectors throughout the basin, we monitored the physical and chemical properties of the tailings as well as the degree of pollution in the soils on four different sampling dates: 5 May, 20 May, 4 June and 22 July 1998. The characteristics of the tailings deposited on the soils are shown to be related to distance from the spill. The oxidation rate of the tailings and the solubilization of the pollutant elements were more pronounced in the middle and lower sectors of the basin, where the particle size was finer, the sulfur content higher and the bulk density less. The increases in water-soluble sulfates, Zn. Cd and Cu were very rapid (the highest values being reached 25 days after the spill) and intense (reaching 45% of the total Cu, 65% of the total Zn and Cd). Meanwhile, the increases in water-soluble As, Bi, Sb, Pb and Tl were far lower (ranging between 0.002% of the total Tl and 2.5% of the total As) and less rapid in the case of As, Bi and Pb (the highest values for these elements being reached 40 days after the spill). These soluble elements infiltrated the soils with the rainwater, swiftly augmenting the soil pollution. Twenty-five days after the spill, when the rainfall ranged between 45 and 63 mm, the first 10-cm of the soils in the middle and lower sectors of the basin exceeded the maximum concentration permitted for agricultural soils in Zn, Cu and Tl. At 40 days after the spill, when the rainfall ranged between 60 and 89 mm, all the soils reached or exceeded the maximum permitted concentrations for As and Tl. Nevertheless, the pollutants tended to concentrate in the first 10 cm of the soils without seriously contaminating either the subsoil or the groundwaters. Consequently, a rapid removal of the tailings and the ploughing of the first 25-30 cm of the soils would be urgent measures to diminish pollutant concentration in the soils affected by the spill.

Decadal Trends in Abundance, Size and Condition of Antarctic Toothfish in McMurdo Sound, Antarctica, 1972-2010

NASA Technical Reports Server (NTRS)

Ainley, David G.; Nur, Nadav; Eastman, Joseph T.; Ballard. Grant; Parkinson, Claire L; Evans, Clive W.; DeVries, Arthur L.

2012-01-01

We report analyses of a dataset spanning 38 years of near-annual fishing for Antarctic toothfish Dissostichus mawsoni, using a vertical setline through the fast ice of McMurdo Sound, Antarctica, 1972-2010. This constitutes one of the longest biological time series in the Southern Ocean, and certainly the longest for any fish. Fish total length, condition and catch per unit effort (CPUE) were derived from the more than 5500 fish caught. Contrary to expectation, length-frequency was dominated by fish in the upper half of the industrial catch. The discrepancy may be due to biases in the sampling capabilities of vertical (this study) versus benthic (horizontal) fishing gear (industry long lines), related to the fact that only large Antarctic toothfish (more than 100 cm TL) are neutrally buoyant and occur in the water column. Fish length and condition increased from the early 1970s to the early 1990s and then decreased, related to sea ice cover, with lags of 8 months to 5 years, and may ultimately be related to the fishery (which targets large fish) and changes in the Southern Annular Mode through effects on toothfish main prey, Antarctic silverfish Pleuragramma antarcticum. CPUE was constant through 2001 and then decreased dramatically, likely related to the industrial fishery, which began in 1996 and which concentrates effort over the Ross Sea slope, where tagged McMurdo fish have been found. Due to limited prey choices and, therefore, close coupling among mesopredators of the Ross Sea, Antarctic toothfish included, the fishery may be altering the trophic structure of the Ross Sea.

Time-loss and non-time-loss injuries in youth football players.

PubMed

Dompier, Thomas P; Powell, John W; Barron, Mary J; Moore, Marguerite T

2007-01-01

Estimates suggest that more than 5.5 million youths play football annually, and 28% of youth football players (age range = 5 to 14 years) are injured each year, resulting in more than 187 000 emergency room visits. To analyze time-loss (TL) and non-time-loss (NTL) injury patterns across age groups in youth football players. Two-year observational cohort. Two midwestern communities, including players from the fourth through eighth grades and between the ages of 9 and 14 years. A total of 779 players participated, including 296 in grades 4 and 5; 203 in grade 6; 188 in grade 7; and 92 in grade 8. (Players in the fourth and fifth grades participated on the same teams, so we considered them as a single group.) Injury frequencies and exposures were collected by certified athletic trainers present at each practice and game and used to calculate injury rates with 95% confidence intervals (CIs) for both TL and NTL injuries across age groups. A total of 474 injuries and 26 565 exposures were identified. Injuries were reported by 36.5% of the players, with 14.4% reporting more than 1 injury in a season. The overall injury rate per 1000 athlete-exposures (A-Es) was 17.8 (95% CI = 16.3, 19.5). The injury rate increased with each succeeding grade from 14.3 per 1000 A-Es (95% CI = 12.1, 16.9) in grades 4 and 5 to 21.7 per 1000 A-Es (95% CI = 17.2, 27.3) in grade 8. A total of 58.6% of all injuries were NTL. Non-time-loss injuries accounted for 70.1% of the injuries reported by fourth and fifth graders, 55.1% by sixth graders, 64.0% by seventh graders, and 33.8% by eighth graders. The cumulative NTL injury rate was 10.5 per 1000 A-Es (95% CI = 9.3, 11.8), and the TL injury rate was 7.4 per 1000 A-Es (95% CI = 6.4, 8.5). Youth football players sustained more NTL injuries than TL injuries. We recommend that a first-aid-certified coach or league official be present at all games and practices.

Task 1: Whole-body concentrations of elements in kelp bass (Paralabrax clathratus), kelp rockfish (Sebastes atrovirens), and Pacific sanddab (Citharichthys sordidus) from offshore oil platforms and natural areas in the Southern California Bight

USGS Publications Warehouse

Love, Milton S.

2009-01-01

Resource managers are concerned that offshore oil platforms in the Southern California Bight may be contributing to environmental contaminants accumulated by marine fishes. To examine this possibility, 18 kelp bass (Paralabrax clathratus), 80 kelp rockfish (Sebastes atrovirens), and 98 Pacific sanddab (Citharichthys sordidus) were collected from five offshore oil platforms and 10 natural areas during 2005-2006 for whole-body analysis of 63 elements. The natural areas, which served as reference sites, were assumed to be relatively uninfluenced by contaminants originating from platforms. Forty-two elements were excluded from statistical comparisons for one of three reasons: they consisted of major cations that were unlikely to accumulate to potentially toxic concentrations under ambient exposure conditions; they were not detected by the analytical procedures; or they were detected at concentrations too low to yield reliable quantitative measurements. The remaining 21 elements consisted of aluminum, arsenic, barium, cadmium, chromium, cobalt, copper, gallium, iron, lead, lithium, manganese, mercury, nickel, rubidium, selenium, strontium, tin, titanium, vanadium, and zinc. Statistical comparisons of these 21 elements indicated that none consistently exhibited higher concentrations at oil platforms than at natural areas. Eight comparisons yielded significant interaction effects between total length (TL) of the fish and the two habitat types (oil platforms and natural areas). This indicated that relations between certain elemental concentrations (i.e., copper, rubidium, selenium, tin, titanium, and vanadium) and habitat type varied by TL of affected fish species. To better understand these interactions, we examined elemental concentrations in very small and very large individuals of affected species. Although significant interactions were detected for rubidium, tin, and selenium in kelp rockfish, the concentrations of these elements did not differ significantly between oil platforms and natural areas over the TL range of sampled fish. However, for selenium, titanium, and vanadium in Pacific sanddab, small individuals (average TL, 13.0 cm) exhibited significantly lower concentrations at oil platforms than at natural areas, whereas large individuals (average TL, 27.5 cm) exhibited higher concentrations at oil platforms than at natural areas. For copper in Pacific sanddab, small individuals did not exhibit differences between oil platforms and natural areas, whereas large individuals exhibited significantly higher concentrations at oil platforms than at natural areas. On the other hand, for tin in Pacific sanddab, small individuals did not exhibit differences between oil platforms and natural areas, whereas large individuals exhibited significantly lower concentrations at oil platforms than at natural areas. Although concentrations of arsenic, cadmium, chromium, lead, mercury, and selenium in fishes from some platforms and natural areas equaled or exceeded literature-based toxicity thresholds for fish and fish-eating wildlife, studies are still needed to document evidence of toxicity from these elements. When estimates of elemental concentrations in skinless fillets were compared to risk-based consumption limits for humans, the concentrations of arsenic, cadmium, mercury, and tin in fish from a mix of oil platforms and natural areas were sufficiently elevated to suggest a need for further study of inorganic arsenic, cadmium, mercury, and tributyltin.

Oxidation/reduction reactions at the metal contact-TlBr interface: an x-ray photoelectron spectroscopy study

NASA Astrophysics Data System (ADS)

Nelson, A. J.; Swanberg, E. L.; Voss, L. F.; Graff, R. T.; Conway, A. M.; Nikolic, R. J.; Payne, S. A.; Kim, H.; Cirignano, L.; Shah, K.

2014-09-01

TlBr radiation detector operation degrades with time at room temperature and is thought to be due to electromigration of Tl and Br vacancies within the crystal as well as the metal contacts migrating into the TlBr crystal itself due to electrochemical reactions at the metal/TlBr interface. X-ray photoemission spectroscopy (XPS) was used to investigate the metal contact surface/interfacial structure on TlBr devices. Device-grade TlBr was polished and subjected to a 32% HCl etch to remove surface damage prior to Mo or Pt contact deposition. High-resolution photoemission measurements on the Tl 4f, Br 3d, Cl 2p, Mo 3d and Pt 4f core lines were used to evaluate surface chemistry and non-equilibrium interfacial diffusion. Results indicate that anion substitution at the TlBr surface due to the HCl etch forms TlBr1-xClx with consequent formation of a shallow heterojunction. In addition, a reduction of Tl1+ to Tl0 is observed at the metal contacts after device operation in both air and N2 at ambient temperature. Understanding contact/device degradation versus operating environment is useful for improving radiation detector performance.

Evidence for topologically protected surface states and a superconducting phase in [Tl4](Tl(1-x)Sn(x))Te3 using photoemission, specific heat, and magnetization measurements, and density functional theory.

PubMed

Arpino, K E; Wallace, D C; Nie, Y F; Birol, T; King, P D C; Chatterjee, S; Uchida, M; Koohpayeh, S M; Wen, J-J; Page, K; Fennie, C J; Shen, K M; McQueen, T M

2014-01-10

We report the discovery of surface states in the perovskite superconductor [Tl4]TlTe3 (Tl5Te3) and its nonsuperconducting tin-doped derivative [Tl4](Tl0.4Sn0.6)Te3 as observed by angle-resolved photoemission spectroscopy. Density functional theory calculations predict that the surface states are protected by a Z2 topology of the bulk band structure. Specific heat and magnetization measurements show that Tl5Te3 has a superconducting volume fraction in excess of 95%. Thus Tl5Te3 is an ideal material in which to study the interplay of bulk band topology and superconductivity.

Individual growth and reproductive behavior in a newly established population of northern snakehead (Channa argus), Potomac River, USA

USGS Publications Warehouse

Landis, Andrew M. Gascho; Lapointe, Nicolas W. R.; Angermeier, Paul L.

2010-01-01

Northern snakehead (Channa argus) were first found in the Potomac River in 2004. In 2007, we documented feeding and reproductive behavior to better understand how this species is performing in this novel environment. From April to October, we used electrofishing surveys to collect data on growth, condition, and gonad weight of adult fish. Growth rates of young were measured on a daily basis for several weeks. Mean length-at-age for Potomac River northern snakehead was lower than for fish from China, Russia, and Uzbekistan. Fish condition was above average during spring and fall, but below average in summer. Below-average condition corresponded to periods of high spawning activity. Gonadosomatic index indicated that females began spawning at the end of April and continued through August. Peak spawning occurred at the beginning of June when average temperatures reached 26°C. Larval fish growth rate, after the transition to exogenous feeding, was 2.3 (SD ± 0.7) mm (total length, TL) per day. Although Potomac River northern snakehead exhibited lower overall growth rates when compared to other populations, these fish demonstrated plasticity in timing of reproduction and rapid larval growth rates. Such life history characteristics likely contribute to the success of northern snakehead in its new environment and limit managers’ options for significant control of its invasion.

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.

Binuclear Pt-Tl bonded complex with square pyramidal coordination around Pt: a combined multinuclear NMR, EXAFS, UV-Vis, and DFT/TDDFT study in dimethylsulfoxide solution.

PubMed

Purgel, Mihály; Maliarik, Mikhail; Glaser, Julius; Platas-Iglesias, Carlos; Persson, Ingmar; Tóth, Imre

2011-07-04

The structure and bonding of a new Pt-Tl bonded complex formed in dimethylsulfoxide (dmso), (CN)(4)Pt-Tl(dmso)(5)(+), have been studied by multinuclear NMR and UV-vis spectroscopies, and EXAFS measurements in combination with density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations. This complex is formed following the equilibrium reaction Pt(CN)(4)(2-) + Tl(dmso)(6)(3+) ⇆ (CN)(4)Pt-Tl(dmso)(5)(+) + dmso. The stability constant of the Pt-Tl bonded species, as determined using (13)C NMR spectroscopy, amounts to log K = 2.9 ± 0.2. The (NC)(4)Pt-Tl(dmso)(5)(+) species constitutes the first example of a Pt-Tl bonded cyanide complex in which the sixth coordination position around Pt (in trans with respect to the Tl atom) is not occupied. The spectral parameters confirm the formation of the metal-metal bond, but differ substantially from those measured earlier in aqueous solution for complexes (CN)(5)Pt-Tl(CN)(n)(H(2)O)(x)(n-) (n = 0-3). The (205) Tl NMR chemical shift, δ = 75 ppm, is at extraordinary high field, while spin-spin coupling constant, (1)J(Pt-Tl) = 93 kHz, is the largest measured to date for a Pt-Tl bond in the absence of supporting bridging ligands. The absorption spectrum is dominated by two strong absorption bands in the UV region that are assigned to MMCT (Pt → Tl) and LMCT (dmso → Tl) bands, respectively, on the basis of MO and TDDFT calculations. The solution of the complex has a bright yellow color as a result of a shoulder present on the low energy side of the band at 355 nm. The geometry of the (CN)(4)Pt-Tl core can be elucidated from NMR data, but the particular stoichiometry and structure involving the dmso ligands are established by using Tl and Pt L(III)-edge EXAFS measurements. The Pt-Tl bond distance is 2.67(1) Å, the Tl-O bond distance is 2.282(6) Å, and the Pt-C-N entity is linear with Pt-C and Pt···N distances amounting to 1.969(6) and 3.096(6) Å, respectively. Geometry optimizations on the (CN)(4)Pt-Tl(dmso)(5)(+) system by using DFT calculations (B3LYP model) provide bond distances in excellent agreement with the EXAFS data. The four cyanide ligands are located in a square around the Pt atom, while the Tl atom is coordinated in a distorted octahedral fashion with the metal being located 0.40 Å above the equatorial plane described by four oxygen atoms of dmso ligands. The four equatorial Tl-O bonds and the four cyano ligands around the Pt atom are arranged in an alternate geometry. The coordination environment around Pt may be considered as being square pyramidal, where the apical position is occupied by the Tl atom. The optimized geometry of (CN)(4)Pt-Tl(dmso)(5)(+) is asymmetrical (C(1) point group). This low symmetry might be responsible for the unusually large NMR linewidths observed due to intramolecular chemical exchange processes. The nature of the Pt-Tl bond has been studied by MO analysis. The metal-metal bond formation in (CN)(4)Pt-Tl(dmso)(5)(+) can be simply interpreted as the result of a Pt(5d(z(2)))(2) → Tl(6s)(0) donation. This bonding scheme may rationalize the smaller thermodynamic stability of this adduct compared to the related complexes with (CN)(5)Pt-Tl entity, where the linear C-Pt-Tl unit constitutes a very stable bonding system. © 2011 American Chemical Society

Studies on 66,67Ga- and 199Tl-poly(N-vinylpyrrolidone) complexes.

PubMed

Lahiri, Susanta; Sarkar, Soumi

2007-03-01

Gallium and thallium radionuclides have both diagnostic and therapeutic applications in the field of nuclear medicine. Poly(N-vinylpyrrolidone) (PVP) is routinely used as a drug base because of its excellent biocompatibility. In this paper, complex formation abilities between no-carrier-added (66,)(67)Ga/(199)Tl radionuclides and PVP have been studied. It has been found that aqueous 5% PVP solution can almost quantitatively back extract (66,)(67)Ga/(199)Tl radionuclides from an organic phase, which proves the complexing ability of PVP with (66,)(67)Ga/(199)Tl. Tl(3+) is more efficient to form Tl-PVP complexes than Tl(+). However, Tl(3+)-PVP complexes are less stable than Ga(3+)-PVP complexes.

High-nuclearity Pt-Tl-Fe complexes: structural, electrochemistry, and spectroelectrochemistry studies.

PubMed

Díez, Alvaro; Fernández, Julio; Lalinde, Elena; Moreno, M Teresa; Sánchez, Sergio

2010-12-20

A series of heteropolynuclear Pt-Tl-Fe complexes have been synthesized and structurally characterized. The final structures strongly depend on the geometry of the precursor and the Pt/Tl ratio used. Thus, the anionic heteroleptic cis-configured [cis-Pt(C(6)F(5))(2)(C≡CFc)(2)](2-) and [Pt(bzq)(C≡CFc)(2)](-) (Fc = ferrocenyl) complexes react with Tl(+) to form discrete octanuclear (PPh(3)Me)(2)[{trans,cis,cis-PtTl(C(6)F(5))(2)(C≡CFc)(2)}(2)] (1), [PtTl(bzq)(C≡CFc)(2)](2) (5; bzq = benzoquinolate), and decanuclear [trans,cis,cis-PtTl(2)(C(6)F(5))(2)(C≡CFc)(2)](2) (3) derivatives, stabilized by both Pt(II)···Tl(I) and Tl(I)···η(2)(alkynyl) bonds. By contrast, Q(2)[trans-Pt(C(6)F(5))(2)(C≡CFc)(2)] (Q = NBu(4)) reacts with Tl(+) to give the one-dimensional (1-D) anionic [(NBu(4)){trans,trans,trans-PtTl(C(6)F(5))(2)(C≡CFc)(2)}](n) (2) and neutral [trans,trans,trans-PtTl(2)(C(6)F(5))(2)(C≡CFc)(2)](n) (4) polymeric chains based on [PtFc(2)](2-) platinate fragments and Tl(+) (2) or [Tl···Tl](2+) (4) units, respectively, connected by Pt(II)···Tl(I) and secondary weak κ-η(1) (2) or η(2) (4) alkynyl···Tl(I) bonding. The formation of 1-4 is reversible, and thus treatment of neutral 3 and 4 with PPh(3)MeBr causes the precipitation of TlBr, returning toward the formation of the anionic 1 and 2' (Q = PPh(3)Me). Two slightly different pseudopolymorphs were found for 2', depending on the crystallization solvent. Finally, the reaction of the homoleptic [Pt(C≡CFc)(4)](2-) with 2 equiv of Tl(+) affords the tetradecanuclear sandwich type complex [Pt(2)Tl(4)(C≡CFc)(8)] (6). Electrochemical, spectroelectrochemical, and theoretical studies have been carried out to elucidate the effect produced by the interaction of the Tl(+) with the Pt-C≡CFc fragments. The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) of 1-5 reveal that, in general, neutralization of the anionic fragments increases the stability of the fully oxidized species and gives higher E(1/2) (Fc) values than those observed in their precursors, increasing with the number of Pt-Tl bonding interactions. However, the electronic communication between Fc groups is reduced or even lost upon Tl(+) coordination, as confirmed by electrochemical (CVs and DPVs voltammograms, 1-5) and spectroelectrochemical (UV-vis-NIR, 2-4) studies. Complexes 2 and 4 still display some electronic interaction between the Fc groups, supported by the presence of an IVCT band in their UV-vis-NIR spectra of oxidized species and additional comparative DFT calculations with the precursor [trans-Pt(C(6)F(5))(2)(C≡CFc)(2)](2-) and complex 3.

In vitro interactions of thallium with components of the glutathione-dependent antioxidant defence system.

PubMed

Villaverde, Marcela S; Hanzel, Cecilia E; Verstraeten, Sandra V

2004-09-01

We investigated the hypothesis that thallium (Tl) interactions with the glutathione-dependent antioxidant defence system could contribute to the oxidative stress associated with Tl toxicity. Working in vitro with reduced glutathione (GSH), glutathione reductase (GR) or glutathione peroxidase (GPx) in solution, we studied the effects of Tl+ and Tl3+ (1-25 microM) on: (a) the amount of free GSH, investigating whether the metal binds to GSH and/or oxidizes it; (b) the activity of the enzyme GR, that catalyzes GSH regeneration; and (c) the enzyme GPx, that reduces hydroperoxide at expense of GSH oxidation. We found that, while Tl+ had no effect on GSH concentration, Tl3+ oxidized it. Both cations inhibited the reduction of GSSG by GR and the diaphorase activity of this enzyme. In addition, Tl3+ per se oxidized NADPH, the cofactor of GR. The effects of Tl on GPx activity depended on the metal charge: Tl+ inhibited GPx when cumene hydroperoxide (CuOOH) was the substrate, while Tl(3+)-mediated GPx inhibition occurred with both substrates. The present results show that Tl interacts with all the components of GSH/GSSG antioxidant defence system. Alterations of this protective pathway could be partially responsible for the oxidative stress associated with Tl toxicity.

Kontekst stratygraficzny zastosowania różnych odmian metody termoluminescencyjnej w datowaniu lessów z terenu Polski południowo-wschodniej i Ukrainy północno-zachodniej

NASA Astrophysics Data System (ADS)

Kusiak, Jarosław

2008-01-01

Loess profiles contain a complex but usually incomplete sequence of deposits. In order to chronologically organize deposit layers accessible in different exposures it is necessary to use absolute dating methods. The 14C, TL and OSL methods are widely used for dating of the Upper Pleistocene deposits whereas to older Pleistocene deposits only luminescence methods are applied. Some attempts are made to use the OSL method for dating of the deposits older than the Upper Pleistocene. However, the OSL ages seem to be consistently lower than the TL ages, and also considerably underestimated with reference to stratigraphic interpretation. This fact indicates that the TL method should be used above all. The possibility of TL dating of loesses is connected with their aeolian origin. The obtained TL age should correspond to geological time when mineral grains constituting deposit were exposed to sunlight before deposition. Such exactly condition is met in case of loess deposits. There are many variants of thermoluminescence method because different measuring procedures can be used. Depending on the used procedure, the TL ages obtained for the same sample can be considerably different. The manner of equivalent dose determination is decisive for the obtained TL ages. The factors influencing the value of equivalent dose are presented in this paper. The equivalent dose is determined by comparison of thermoluminescence measured for a given sample with thermoluminescence of the same sample after irradiation in laboratory with known doses of ionizing radiation. The following criteria should be taken into account: size of mineral grains, relation between thermoluminescence and heating temperature, way of reduction of unstable thermoluminescence, and the results of plateau test. The variant of thermoluminescence method used in the TL Laboratory of the Department of Physical Geography and Palaeogeography, Maria Curie-Skłodowska University in Lublin is as follows. The dose rate is determined by gamma spectrometry. The equivalent dose is determined by the total-bleach technique for the 45-63 μm fraction. Blue light obtained using the BG-28 filter is applied. Samples are preheated at 160°C for 3 hours before measurement. Light sum is read as the maximum height of glow curve. The application of such measurement procedure allows reliable dating of climatic episodes recorded in loess deposits not only related to the last glacial but also in older ones.

Optimization and comparison of simultaneous and separate acquisition protocols for dual isotope myocardial perfusion SPECT

PubMed Central

Ghaly, Michael; Links, Jonathan M; Frey, Eric C

2015-01-01

Dual-isotope simultaneous-acquisition (DISA) rest-stress myocardial perfusion SPECT (MPS) protocols offer a number of advantages over separate acquisition. However, crosstalk contamination due to scatter in the patient and interactions in the collimator degrade image quality. Compensation can reduce the effects of crosstalk, but does not entirely eliminate image degradations. Optimizing acquisition parameters could further reduce the impact of crosstalk. In this paper we investigate the optimization of the rest Tl-201 energy window width and relative injected activities using the ideal observer (IO), a realistic digital phantom population and Monte Carlo (MC) simulated Tc-99m and Tl-201 projections as a means to improve image quality. We compared performance on a perfusion defect detection task for Tl-201 acquisition energy window widths varying from 4 to 40 keV centered at 72 keV for a camera with a 9% energy resolution. We also investigated 7 different relative injected activities, defined as the ratio of Tc-99m and Tl-201 activities, while keeping the total effective dose constant at 13.5 mSv. For each energy window and relative injected activity, we computed the IO test statistics using a Markov chain Monte Carlo (MCMC) method for an ensemble of 1,620 triplets of fixed and reversible defect-present, and defect-absent noisy images modeling realistic background variations. The volume under the 3-class receiver operating characteristic (ROC) surface (VUS) was estimated and served as the figure of merit. For simultaneous acquisition, the IO suggested that relative Tc-to-Tl injected activity ratios of 2.6–5 and acquisition energy window widths of 16–22% were optimal. For separate acquisition, we observed a broad range of optimal relative injected activities from 2.6 to 12.1 and acquisition energy window of widths 16–22%. A negative correlation between Tl-201 injected activity and the width of the Tl-201 energy window was observed in these ranges. The results also suggested that DISA methods could potentially provide image quality as good as that obtained with separate acquisition protocols. We compared observer performance for the optimized protocols and the current clinical protocol using separate acquisition. The current clinical protocols provided better performance at a cost of injecting the patient with approximately double the injected activity of Tc-99m and Tl-201, resulting in substantially increased radiation dose. PMID:26083239

An indirect ELISA for detection of Theileria spp. antibodies using a recombinant protein (rTlSP) from Theileria luwenshuni.

PubMed

He, Haining; Li, Youquan; Liu, Junlong; Liu, Zhijie; Yang, Jifei; Liu, Aihong; Chen, Ze; Ren, Qiaoyun; Guan, Guiquan; Liu, Guangyuan; Luo, Jianxun; Yin, Hong

2016-07-01

Theileria is a tick-borne, intracellular protozoan parasite of worldwide economic and veterinary importance in small ruminants. Here, an enzyme-linked immunosorbent assay (ELISA) was developed based on Theileria luwenshuni recombinant surface protein (rTlSP) and was used in the standardization and validation of an ELISA for the detection of circulating antibodies against ovine and caprine theileriosis. A total of 233 sera samples were used for the calculation of the cut-off value which served as a threshold between the positive and the negative sera. When the positive threshold was chosen as 19% of the specific mean antibody rate, the specificity was 97.9%, and the sensitivity was 97.1%. There was a cross-reaction with sera against Theileria uilenbergi and Theileria ovis, and no cross-reaction with sera against Babesia spp. in the ELISA and Western blotting. Two hundred forty samples collected from sheep in Gansu province were detected with blood smears and ELISA, respectively. The results showed that the positive rate of Theileria infection in Gansu province were 63.75% with rTlSP-ELISA, and 46.67% with blood smears, respectively. Our test proved that the rTlSP ELISA is suitable to diagnose Theileria infection and could be used in serological surveys to map out the prevalence of ovine and caprine theileriosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Pollution Characteristics and Possible Sources of Seldom Monitored Trace Elements in Surface Sediments Collected from Three Gorges Reservoir, China

PubMed Central

Gao, Bo; Wei, Xin; Zhou, Huaidong; Lu, Jin; Hao, Hong; Wan, Xiaohong

2014-01-01

A geochemical study of Three Gorges Reservoir (TGR) sediments was carried out to analyze the concentrations, distribution, accumulation, and potential sources of the seldom monitored trace elements (SMTEs). The mean concentrations of Li, B, Be, Bi, V, Co, Ga, Sn, Sb, and Tl were 47.08, 2.47, 59.15, 0.50, 119.20, 17.83, 30.31, 3.25, 4.14, and 0.58 mg/kg, respectively. The concentrations of total SMTEs, together with their spatial distribution, showed that the SMTEs were mainly due to anthropogenic inputs in the region of TGR. The assessment by Geoaccumulation Index indicates that Tl, Be, V, Co, and Fe are at the unpolluted level; Bi, Li, Ga, and Sn were at the “uncontaminated to moderately contaminated” level. However, B was classified as “moderately contaminated” level and Sb was ranked as “strongly contaminated” level. The pollution level of the SMTEs is Sb > B > Bi > Li > Ga > Sn > Tl > Be > V > Co > Fe. The results of Correlation Analysis and Principal Component Analysis indicated Be, V, Co, Ga, Sn, Tl, Bi, and Fe in sediments have a natural source. B and Li were positively correlated with each other and mainly attributed into similar anthropogenic input. In addition, Sb has less relationship with other SMTEs, indicating that Sb has another kind of anthropogenic source. PMID:25136647

Application and validation of superior spectrophotometric methods for simultaneous determination of ternary mixture used for hypertension management.

PubMed

Mohamed, Heba M; Lamie, Nesrine T

2016-02-15

Telmisartan (TL), Hydrochlorothiazide (HZ) and Amlodipine besylate (AM) are co-formulated together for hypertension management. Three smart, specific and precise spectrophotometric methods were applied and validated for simultaneous determination of the three cited drugs. Method A is the ratio isoabsorptive point and ratio difference in subtracted spectra (RIDSS) which is based on dividing the ternary mixture of the studied drugs by the spectrum of AM to get the division spectrum, from which concentration of AM can be obtained by measuring the amplitude values in the plateau region at 360nm. Then the amplitude value of the plateau region was subtracted from the division spectrum and HZ concentration was obtained by measuring the difference in amplitude values at 278.5 and 306nm (corresponding to zero difference of TL) while the total concentration of HZ and TL in the mixture was measured at their isoabsorptive point in the division spectrum at 278.5nm (Aiso). TL concentration is then obtained by subtraction. Method B; double divisor ratio spectra derivative spectrophotometry (RS-DS) and method C; mean centering of ratio spectra (MCR) spectrophotometric methods. The proposed methods did not require any initial separation steps prior the analysis of the three drugs. A comparative study was done between the three methods regarding their; simplicity, sensitivity and limitations. Specificity was investigated by analyzing the synthetic mixtures containing different ratios of the three studied drugs and their tablets dosage form. Statistical comparison of the obtained results with those found by the official methods was done, differences were non-significant in regard to accuracy and precision. The three methods were validated in accordance with ICH guidelines and can be used for quality control laboratories for TL, HZ and AM. Copyright © 2015 Elsevier B.V. All rights reserved.

Application and validation of superior spectrophotometric methods for simultaneous determination of ternary mixture used for hypertension management

NASA Astrophysics Data System (ADS)

Mohamed, Heba M.; Lamie, Nesrine T.

2016-02-01

Telmisartan (TL), Hydrochlorothiazide (HZ) and Amlodipine besylate (AM) are co-formulated together for hypertension management. Three smart, specific and precise spectrophotometric methods were applied and validated for simultaneous determination of the three cited drugs. Method A is the ratio isoabsorptive point and ratio difference in subtracted spectra (RIDSS) which is based on dividing the ternary mixture of the studied drugs by the spectrum of AM to get the division spectrum, from which concentration of AM can be obtained by measuring the amplitude values in the plateau region at 360 nm. Then the amplitude value of the plateau region was subtracted from the division spectrum and HZ concentration was obtained by measuring the difference in amplitude values at 278.5 and 306 nm (corresponding to zero difference of TL) while the total concentration of HZ and TL in the mixture was measured at their isoabsorptive point in the division spectrum at 278.5 nm (Aiso). TL concentration is then obtained by subtraction. Method B; double divisor ratio spectra derivative spectrophotometry (RS-DS) and method C; mean centering of ratio spectra (MCR) spectrophotometric methods. The proposed methods did not require any initial separation steps prior the analysis of the three drugs. A comparative study was done between the three methods regarding their; simplicity, sensitivity and limitations. Specificity was investigated by analyzing the synthetic mixtures containing different ratios of the three studied drugs and their tablets dosage form. Statistical comparison of the obtained results with those found by the official methods was done, differences were non-significant in regard to accuracy and precision. The three methods were validated in accordance with ICH guidelines and can be used for quality control laboratories for TL, HZ and AM.

Thallium isotope variations in an ore-bearing continental igneous setting: Collahuasi Formation, northern Chile

NASA Astrophysics Data System (ADS)

Baker, R. G. A.; Rehkämper, M.; Ihlenfeld, C.; Oates, C. J.; Coggon, R.

2010-08-01

Thallium is a highly incompatible element and a large fraction of the bulk silicate Earth Tl budget is, therefore, expected to reside in the continental crust. Nonetheless, the Tl isotope systematics of continental rocks are essentially unexplored at present. Here, we present new Tl isotope composition and concentration data for a suite of 36 intrusive and extrusive igneous rocks from the vicinity of porphyry Cu deposits in the Collahuasi Formation of the Central Andes in northern Chile. The igneous lithologies of the rocks are variably affected by the hydrothermal alteration that accompanied the formation of the Cu deposits. The samples display Tl concentrations that vary by more than an order of magnitude, from 0.1 to 3.2 μg/g, whilst ɛ 205Tl ranges between -5.1 and +0.1 (ɛ 205Tl is the deviation of the 205Tl/ 203Tl isotope ratio of a sample from a standard in parts per 10 4). These variations are primarily thought to be a consequence of hydrothermal alteration processes, including metasomatic transport of Tl, and formation/breakdown of Tl-bearing minerals, which are associated with small but significant Tl isotope effects. The Tl abundances show excellent correlations with both K and Rb concentrations but no co-variation with Cu. This demonstrates that Tl displays only limited chalcophile affinity in the continental crust of the Collahuasi Formation, but behaves as a lithophile element with a distribution that is primarily governed by partitioning of Tl + into K +-bearing phases. Collahuasi samples with propylitic alteration features, which are derived from the marginal parts of the hydrothermal systems, have, on average, slightly lighter Tl isotope compositions than rocks from the more central sericitic and argillic alteration zones. This small but statistically significant difference most likely reflects preferential retention of isotopically heavy Tl in alteration phases, such as white micas and clays, which formed during sericitic and argillic alteration.

Characterization of seed storage protein patterns of Heliotropium digynum.

PubMed

Alwhibi, Mona Soliman

2017-09-01

Heliotropium digynum , is a shrub that has ecological importance. The height of the plant differs from one population to another and the difference in length of the inflorescence can be attributed to environmental factors, such as rainfall or type of soil and temperature. To date, no study has shed light on estimation in seed samples of H. digynum in Saudi Arabia. So, the aim is to evaluate and characterize the protein patterns of seed storage proteins of H. digynum to be used as fingerprint of this plant in Saudi Arabia. It is collected from different locations in the central region of Saudi Arabia and total protein extraction from plant was compared in SDS-PAGE. The genetic relationships among all cultivars were analyzed using UPGMA and NJ using Total Lab TL and in the same way using Jaccard Similarity Coefficient dendrogram using STATISTICA (ver.8) software. Results, our data show that amounts of protein are different, although they are of the same type or from the same geographical region. Amounts ranged between 22 and 1.5 mg/g of dry weight. Less amount of protein was obtained from the group of samples collected from Dir'iyah area, and the highest amount of protein was from the group of samples collected from Dyrab area in general.

AsS-Tl/sub 3/AsS/sub 4/ and AsS-Tl/sub 2/S systems

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

Vorob'ev, Yu.I.; Velikova, N.G.; Kirilenko, V.V.

1987-11-01

Using DTA and XPA as well as microstructural analysis and microhardness measurements, the AsS-Tl/sub 3/AsS/sub 4/ and AsS-Tl/sub 2/S phase diagrams are studied. Two new ternary compounds, Tl/sub 2/As/sub 3/S/sub 4/ and Tl/sub 2/As/sub 2/S/sub 3/, are revealed and their interplanar distances are calculated.

Discovering the balance of steric and electronic factors needed to provide a new structural motif for photocatalytic hydrogen production from water.

PubMed

White, Travis A; Whitaker, Brittany N; Brewer, Karen J

2011-10-05

Ru,Rh,Ru supramolecules are known to undergo multielectron photoreduction and reduce H(2)O to H(2). Ru,Rh bimetallics were recently shown to photoreduce but not catalyze H(2)O reduction. Careful tuning of sterics and electronics for [(TL)(2)Ru(dpp)RhCl(2)(TL')](3+) produce active bimetallic photocatalysts (TL = terminal ligand). The system with TL,TL' = Ph(2)phen photocatalytically reduces H(2)O to H(2) while TL,TL' = phen,bpy or bpy,(t)Bu(2)bpy do not.

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.

The Shubnikov-de Haas effect and thermoelectric properties of Tl-doped Sb{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3}

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

Kulbachinskii, V. A., E-mail: kulb@mig.phys.msu.ru; Kudryashov, A. A.; Kytin, V. G.

2015-06-15

The influence of doping with Tl on the Shubnikov-de Haas effect at T = 4.2 K in magnetic fields up to 38 T in p-Sb{sub 2−x}Tl{sub x}Te{sub 3} (x = 0, 0.005, 0.015, and 0.05) and n-Bi{sub 2−x}Tl{sub x}Se{sub 3} (x = 0, 0.01, 0.02, 0.04, and 0.06) single crystals is investigated. Extreme cross-sections of the Fermi surface in both materials decrease upon doping with Tl: the hole concentration decreases in Sb{sub 2−x}Tl{sub x}Te{sub 3} due to the donor effect of Tl and the electron concentration in n-Bi{sub 2−x}Tl{sub x}Se{sub 3} decreases due to the acceptor effect of Tl. Themore » temperature dependences of the Seebeck coefficient, electrical conductivity, thermal conductivity, and dimensionless thermoelectric figure of merit in a temperature range of 77–300 K are measured. The thermal conductivity and electrical conductivity decrease upon doping with Tl both in p-Sb{sub 2−x}Tl{sub x}Te{sub 3} and in n-Bi{sub 2−x}Tl{sub x}Se{sub 3}. The Seebeck coefficient increases in all compositions upon an increase in doping over the entire measured temperature range. The thermoelectric figure of merit increases upon doping with Tl.« less

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.

Assessing the genotoxic potential of chlorothalonil drift from potato fields in Prince Edward Island, Canada.

PubMed

Garron, Christine; Knopper, Loren D; Ernst, William R; Mineau, Pierre

2012-02-01

Chlorothalonil, a broad-spectrum nonsystemic foliar fungicide, is one of the most extensively used pesticide active ingredients on Prince Edward Island, Canada, for blight control on potatoes. In ambient air-sampling programs conducted in 1998 and 1999 and from 2002 to 2004, chlorothalonil was measured in 97% of air samples collected. It is known to produce severe eye and skin irritation, is cytogenic and is considered a possible human carcinogen by the United States Environmental Protection Agency and the International Agency for Research on Cancer. Inhalation studies that quantify chlorothalonil subchronic effects (e.g., genotoxicity) are lacking. The purpose of this study was to assess the possible genotoxic potential of chlorothalonil under field conditions by using the alkaline comet assay to assess DNA damage in CD-1 mice. Mice were selected as a surrogate species for wild small mammals (e.g., meadow voles, deer mice) known to inhabit areas adjacent to potato fields. Mice were placed at three locations downwind of a chlorothalonil application (0, 30, and 100 m) and at one up-wind control location at least 30 m from the field. Downwind mice were exposed to drift throughout the spray period (approximately 30 min) and for an additional hour after spraying. Air samples were collected during the spray trials (before, during, and after spraying) using high-volume polyurethane foam and PM(2.5) air samplers. Pesticide deposits were measured using 20 × 25 cm glass-fibre filters. After exposure, blood was collected from each mouse, and DNA strand breaks in white blood cells measured using comet assay. Results suggest that metrics of DNA damage [tail length (TL), percent DNA in tail] were not significantly related to total air chlorothalonil concentration from the three spray trials (r (2) = 0.000, P = 0.907 for TL; r (2) = 0.001, P = 0.874 for percent DNA). In addition, no significant difference in DNA damage was observed between exposed (at 0 m) and control animals (P = 0.357 for TL; P = 0.958 for percent DNA). Based on these results it can be concluded that wild small mammals living beside fields sprayed with chlorothalonil are at no greater risk of exposure-related DNA damage than conspecifics from unexposed areas.

Alteration of mineral crystallinity and collagen cross-linking of bones in osteopetrotic toothless (tl/tl) rats and their improvement after treatment with colony stimulating factor-1

NASA Technical Reports Server (NTRS)

Wojtowicz, A.; Dziedzic-Goclawska, A.; Kaminski, A.; Stachowicz, W.; Wojtowicz, K.; Marks, S. C. Jr; Yamauchi, M.

1997-01-01

A common feature of various types of mammalian osteopetroses is a marked increase in bone mass accompanied by spontaneous bone fractures. The toothless (tl/tl) rat osteopetrotic mutation is characterized by drastically reduced bone resorption due to a profound deficiency of osteoclasts and their precursors. An altered bone morphology has also been observed. The mutants cannot be cured by bone marrow transplantation, but skeletal defects are greatly reduced after treatment with colony stimulating factor 1 (CSF-1). The objectives of this study were to characterize mineral and collagen matrices in cancellous and compact bone isolated from long bones of 6-week-old normal littermates, tl/tl osteopetrotic mutants and mutants (tl/tl) treated with CSF-1. There were no differences in bone mineral content, but a significant decrease in the crystallinity of mineral evaluated by the method based on electron paramagnetic resonance spectrometry was observed in all bones of tl/tl mutants as compared to that of controls. Within the collagen matrix, slight decreases in the labile cross-links, but significant increases in the content of the stable cross-links, pyridinoline, and deoxypyridinoline, were observed in both cancellous and compact bone of osteopetrotic mutants. In tl/tl mutants treated with human recombinant CSF-1, the normalization of the crystallinity of bone mineral as well as collagen cross-links was found. Our results indicate that remodeling of bone matrix in tl/tl mutants is highly suppressed, but that after treatment with CSF-1, this activity recovers significantly. Taken together, these data provide further support for the hypothesis that CSF-1 is an essential factor for normal osteoclast differentiation and bone remodelling.

Biodistribution of iodine-125 and indium-111 labeled OV-TL 3 intact antibodies and F(ab')2 fragments in tumor-bearing athymic mice.

PubMed

Massuger, L F; Boerman, O C; Corstens, F H; Verheijen, R H; Claessens, R A; Poels, L G; van den Broek, W J; Kenemans, P

1991-01-01

The monoclonal antibody OV-TL 3, directed against an ovarian carcinoma-associated antigenic determinant, was tested as a vehicle for radioimmunolocalization of ovarian carcinomas in athymic mice bearing NIH:OVCAR-3 xenografts. The biodistribution of intact. OV-TL 3 was compared with the distribution of OC 125. Tumor uptake with OV-TL 3 was significantly higher than with OC 125, and almost 7 times higher than with a non-specific control antibody (OV-TL 19). Administration of a mixture of intact OV-TL 3 and OC 125 did not improve tumor uptake in comparison with OV-TL 3 alone. Subsequently, intact OV-TL 3 and its F(ab')2 fragments were labeled with either 111In or 125I. The highest tumor uptake was obtained with 111In-labeled intact OV-TL 3 (14.7% ID/g, 48 hr p.i.). For both antibody forms uptake of 111In in liver, spleen and kidneys was very high. Furthermore, 111In cleared more slowly from most tissues than 125I. As a result, tumor/tissue ratios with 111In-labeled OV-TL 3 were lower than with 125I-labeled OV-TL 3. The highest tumor/tissue ratios (6.9 to 53) were obtained with 125I-labeled OV-TL 3 F(ab')2 fragments, 48 hr post injection. 111In-labeled OV-TL 3 F(ab')2 has already been shown to be a clinically useful label for the detection of ovarian cancer. The results of our comparative animal study suggest that these clinical results may even be improved by using 123I-labeled OV-TL 3 F(ab')2.

Study of constraints in using household NaCl salt for retrospective dosimetry

NASA Astrophysics Data System (ADS)

Elashmawy, M.

2018-05-01

Thermoluminescence (TL) characteristics of 5 different household NaCl salts and one analytical salt were determined to investigate the possible factors that affect the reliability of using household salt for retrospective dosimetry. Salts' TL sensitivities were found to be particle-size dependent and approached saturation at the largest size, whereas for salts that have the same particle size, the TL sensitivity depended on their origin. TL dependence on the particle size interprets significant variations in TL response reported in the literature for the same salt patch. The first TL readout indicated that all salts have similar glow curves with one distinctive peak. Typical second TL readout at two different doses showed a dramatic decrease in TL sensitivity associated with a significant change in the glow curve structure possessing two prominent peaks. Glow curve deconvolution (GCD) of the first TL readout for all salts yielded 6 individual glow peaks of first-order kinetics, whereas in GCD of second TL readouts, 5 individual glow peaks of second-order kinetics were obtained. Similarities in the glow curve structures of the first and second TL readouts suggest that additives such as KIO3 and MgCO3 have no effect on the TL process. Fading effect was evaluated for the salt of highest TL sensitivity, and it was found that the integral TL intensity decreased gradually and lost 40% of its initial value over 2 weeks, after which it remained constant. Results conclude that a household salt cannot be used for retrospective dosimetry without considering certain constraints such as the salt's origin and particle size. Furthermore, preparedness for radiological accidents and accurate dose reconstructions require that most of the commonly distributed household salt brands should be calibrated in advance and stored in a repository to be recalled in case of accidents.

Special Operations Forces Language and Culture Needs Assessment: Immersion Training

DTIC Science & Technology

2010-11-01

in TL Listen in TL Train or teach other in TL Conduct business negotiations in TL Use TL to maintain control Use TL to persuade people Use informal... teach what you’re going to do, you do a practical exercise where they’re integrating, the person’s integrating what you just taught them in a...1990). Investigating fluency in EFL : A quantitative approach. Language Learning, 3, 387– 417. Owens, W. (2010). Improving cultural education of Special

Masking ability of bi- and tri- laminate all-ceramic veneers on tooth-colored ceramic discs.

PubMed

Farhan, Daniel; Sukumar, Smitha; von Stein-Lausnitz, Axel; Aarabi, Ghazal; Alawneh, Ahmad; Reissmann, Daniel R

2014-01-01

A predictable esthetic outcome is imperative when placing ceramic veneers. Discolored teeth pose a major challenge as sufficient material thickness is required to achieve a good esthetic result. There is limited evidence in the literature that compares the masking ability of multi-laminate veneers. The aim of this in-vitro study was to compare the masking ability of bi-laminate (BL) and tri-laminate (TL) all-ceramic veneers cemented on tooth-colored ceramic discs. A total of 40 veneers (shade A1, 10-mm diameter, 0.8-mm thick) were manufactured-20 BL veneers (0.4-mm pressable ceramic coping veneered with 0.4-mm thick enamel layer) and 20 TL veneers (0.4-mm coping veneered with 0.2-mm thick opaque interlayer and 0.2-mm thick enamel layer). A bonding apparatus was utilized to adhesively cement all veneers on the ceramic discs (shade A1), simulating teeth of light and dark color. The resulting groups (N = 10 each) were the reference groups (shade A1 ceramic base) BL-1 and TL-1 veneers, and the test groups (shade A4 ceramic base) BL-4 and TL-4 veneers. The color of the cemented veneers was measured using a spectrophotometer. The data were converted to CIE L*a*b* coordinates, and ΔE* were calculated to allow for statistical analysis. The color differences between the samples with the A1 and A4 ceramic bases were significantly lower when covered with TL veneers (mean ΔE*: 3.2 units) than with BL veneers (mean ΔE*: 4.0 units: p < 0.001), indicating a better masking ability of the TL veneers. The 0.8-mm thick TL veneer was able to mask darker tooth-colored ceramic disc within clinically acceptable limits. Increased understanding of the masking ability of ceramics and of color science is necessary in these esthetically aware times. Providing tri-laminate veneers for darker colored teeth seems to result in more predictable esthetical results than when using bi-laminate veneers. Patients with discolored/darker teeth may benefit from a more predictable esthetic result when teeth restored with tri-laminate rather than bi-laminate veneers. © 2014 Wiley Periodicals, Inc.

Analysis of the SPS Long Term Orbit Drifts

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

Velotti, Francesco; Bracco, Chiara; Cornelis, Karel

2016-06-01

The Super Proton Synchrotron (SPS) is the last accelerator in the Large Hadron Collider (LHC) injector chain, and has to deliver the two high-intensity 450 GeV proton beams to the LHC. The transport from SPS to LHC is done through the two Transfer Lines (TL), TI2 and TI8, for Beam 1 (B1) and Beam 2 (B2) respectively. During the first LHC operation period Run 1, a long term drift of the SPS orbit was observed, causing changes in the LHC injection due to the resulting changes in the TL trajectories. This translated into longer LHC turnaround because of the necessitymore » to periodically correct the TL trajectories in order to preserve the beam quality at injection into the LHC. Different sources for the SPS orbit drifts have been investigated: each of them can account only partially for the total orbit drift observed. In this paper, the possible sources of such drift are described, together with the simulated and measured effect they cause. Possible solutions and countermeasures are also discussed.« less

Shape-Coexistence in ^191Tl and ^189Tl.

NASA Astrophysics Data System (ADS)

Reviol, W.; Riedinger, L. L.; Carpenter, M. P.; Fischer, S. M.; Janssens, R. V. F.; Nisius, D.; Moore, E. F.

1997-10-01

The Tl isotopes at A ~ 190 are, like the neighboring Hg and Pb nuclei, recognized for a multiplicity of shapes. These shapes reach from spherical or weakly deformed oblate to well-deformed and superdeformed prolate, as mainly inferred from γ -ray spectroscopic studies. We have previously reported on shape-coexistence phenomena in ^191Tl and ^189Tl(W. Reviol et al., Phys. Scr. T56, 167 (1995), and references therein.). Here, we will focus on new results on the ``normally" deformed states in both nuclei obtained from a recent and an upcoming experiment at GAMMASPHERE. The states in ^191Tl and ^189Tl are populated by the reactions ^159Tb(^36S,4n)^191Tl at E_lab = 165 MeV and ^156Gd(^37Cl,4n)^189Tl at E_lab = 171 MeV, respectively. One of the questions to be addressed is about the main level structure in the positive-parity branch of ^191Tl^2. Whether this structure is oblate-collective in nature, like the [505]9/2^- yrast band, we will try to answer on the basis of the available lifetime data.

A comparative study on the antioxidant activity of methanolic extracts from different parts of Morus alba L. (Moraceae)

PubMed Central

2013-01-01

Background Antioxidants play an important role to protect damage caused by oxidative stress (OS). Plants having phenolic contents are reported to possess antioxidant properties. The present study was designed to investigate the antioxidant properties and phenolic contents (total phenols, flavonoids, flavonols and proanthrocyanidins) of methanolic extracts from Morus alba (locally named as Tut and commonly known as white mulberry) stem barks (TSB), root bark (TRB), leaves (TL) and fruits (TF) to make a statistical correlation between phenolic contents and antioxidant potential. Methods The antioxidant activities and phenolic contents of methanolic extractives were evaluated by in vitro standard method using spectrophotometer. The antioxidant activities were determined by total antioxidant capacity, DPPH (1,1-diphenyl-2-picrylhydrazine) radical scavenging assay, hydroxyl radical scavenging assay, ferrous reducing antioxidant capacity and lipid peroxidation inhibition assay methods. Results Among the extracts, TSB showed the highest antioxidant activity followed by TRB, TF and TL. Based on DPPH and hydroxyl radical scavenging activity, the TSB extract was the most effective one with IC50 37.75 and 58.90 μg/mL, followed by TRB, TF and TL with IC50 40.20 and 102.03; 175.01 and 114.63 and 220.23 and 234.63 μg/mL, respectively. The TSB extract had the most potent inhibitory activity against lipid peroxidation with IC50 145.31 μg/mL. In addition, the reducing capacity on ferrous ion was in the following order: TSB > TRB > TL > TF. The content of phenolics, flavonoids, flavonols and proanthocyanidins of TSB was found to be higher than other extractives. Conclusion The results indicate high correlation and regression (p-value <0 .001) between phenolic contents and antioxidant potentials of the extracts, hence the Tut plant could serve as effective free radical inhibitor or scavenger which may be a good candidate for pharmaceutical plant-based products. However, further exploration is necessary for effective use in both modern and traditional system of medicines. PMID:23331970

Optimal formation and enhanced superconductivity of Tl-1212 phase (Tl0.6Pb0.4)(Ba,Sr)CaCu2O7

NASA Astrophysics Data System (ADS)

Ranjbar, M. G.; Ghoranneviss, Mahmood; Abd-Shukor, R.

2018-06-01

The effect of heating temperature on the formation of Tl-1212 phase with nominal starting composition (Tl0.6Pb0.4)(Ba,Sr)CaCu2O7 (Tl-1212) is reported. The Ba-bearing Tl-1212 phase is normally prepared at around 900 °C while with Sr-bearing sample is prepared at a much higher temperature of around 1000 °C. This work was conducted to determine the optimal temperature to synthesis the Tl-1212 phase when the sample contains Ba and Sr with 1:1 ratio. (Tl0.6Pb0.4)(Ba,Sr)CaCu2O7 samples were prepared using the solid-state reaction method via the precursor route. In the final preparation stage, the samples were heated at 850, 870, 900, 920, 950, 970 and 1000 °C in oxygen flow. X-Ray diffraction patterns showed that most samples consisted of a mixed (Tl0.6Pb0.4)(Ba,Sr)Ca2Cu3O9 (Tl-1223) and Tl-1212 phase except for the sample heated at 970 °C which showed a single Tl-1212 phase and the sample heated at 850 °C which showed the Tl-1223 phase. The transition temperature measured by four-probe method showed that the sample heated at 970 °C exhibited the highest onset temperature of 118 K and zero-resistance temperature of 100 K. This transition temperature is higher than the usually reported value for the Tl-1212 phase. AC susceptibility measurements also showed the 970 °C heated sample with the highest transition temperature T c χ' = 109 K. The interplay of ionic radius (Ba2+ and Sr2+) decreases of the unit cell volume and changes in the internal lattice strain enhanced the transition temperature and the formation of the Tl-1212 phase.

Tl And Osl Response Of Turquoise For Dosimetric Application

NASA Astrophysics Data System (ADS)

Subedi, B.; Afouxenidis, D.; Polymeris, G. S.; Tsirlignanis, N.; Paraskevopoulos, K. M.; Kitis, G.

Turquoise is one of the amongst first gem stones used in jewelry and possessing cultural value since 2000 BC (at least). This work attempts characterize this stone scientifically using both thermally (TL) and optically stimulated luminescence (OSL) techniques. The experimental investigation included 1) the study of the natural TL and OSL signals, 2) the reproducibility of TL sensitivity over repeated irradiation and TL readout cycles, 3) dependence of sensitivity on annealing temperatures and 4) the TL and OSL dose response curves. The potential use of the TL and OSL techniques in determination of provenance, accidental dosimetry and probably to authenticity and dating purposes are then discussed.

Iron Deficiency Induces a Partial Inhibition of the Photosynthetic Electron Transport and a High Sensitivity to Light in the Diatom Phaeodactylum tricornutum.

PubMed

Roncel, Mercedes; González-Rodríguez, Antonio A; Naranjo, Belén; Bernal-Bayard, Pilar; Lindahl, Anna M; Hervás, Manuel; Navarro, José A; Ortega, José M

2016-01-01

Iron limitation is the major factor controlling phytoplankton growth in vast regions of the contemporary oceans. In this study, a combination of thermoluminescence (TL), chlorophyll fluorescence, and P700 absorbance measurements have been used to elucidate the effects of iron deficiency in the photosynthetic electron transport of the marine diatom P. tricornutum. TL was used to determine the effects of iron deficiency on photosystem II (PSII) activity. Excitation of iron-replete P. tricornutum cells with single turn-over flashes induced the appearance of TL glow curves with two components with different peaks of temperature and contributions to the total signal intensity: the B band (23°C, 63%), and the AG band (40°C, 37%). Iron limitation did not significantly alter these bands, but induced a decrease of the total TL signal. Far red excitation did not increase the amount of the AG band in iron-limited cells, as observed for iron-replete cells. The effect of iron deficiency on the photosystem I (PSI) activity was also examined by measuring the changes in P700 redox state during illumination. The electron donation to PSI was substantially reduced in iron-deficient cells. This could be related with the important decline on cytochrome c 6 content observed in these cells. Iron deficiency also induced a marked increase in light sensitivity in P. tricornutum cells. A drastic increase in the level of peroxidation of chloroplast lipids was detected in iron-deficient cells even when grown under standard conditions at low light intensity. Illumination with a light intensity of 300 μE m(-2) s(-1) during different time periods caused a dramatic disappearance in TL signal in cells grown under low iron concentration, this treatment not affecting to the signal in iron-replete cells. The results of this work suggest that iron deficiency induces partial blocking of the electron transfer between PSII and PSI, due to a lower concentration of the electron donor cytochrome c 6. This decreased electron transfer may induce the over-reduction of the plastoquinone pool and consequently the appearance of acceptor side photoinhibition in PSII even at low light intensities. The functionality of chlororespiratory electron transfer pathway under iron restricted conditions is also discussed.

Iron Deficiency Induces a Partial Inhibition of the Photosynthetic Electron Transport and a High Sensitivity to Light in the Diatom Phaeodactylum tricornutum

PubMed Central

Roncel, Mercedes; González-Rodríguez, Antonio A.; Naranjo, Belén; Bernal-Bayard, Pilar; Lindahl, Anna M.; Hervás, Manuel; Navarro, José A.; Ortega, José M.

2016-01-01

Iron limitation is the major factor controlling phytoplankton growth in vast regions of the contemporary oceans. In this study, a combination of thermoluminescence (TL), chlorophyll fluorescence, and P700 absorbance measurements have been used to elucidate the effects of iron deficiency in the photosynthetic electron transport of the marine diatom P. tricornutum. TL was used to determine the effects of iron deficiency on photosystem II (PSII) activity. Excitation of iron-replete P. tricornutum cells with single turn-over flashes induced the appearance of TL glow curves with two components with different peaks of temperature and contributions to the total signal intensity: the B band (23°C, 63%), and the AG band (40°C, 37%). Iron limitation did not significantly alter these bands, but induced a decrease of the total TL signal. Far red excitation did not increase the amount of the AG band in iron-limited cells, as observed for iron-replete cells. The effect of iron deficiency on the photosystem I (PSI) activity was also examined by measuring the changes in P700 redox state during illumination. The electron donation to PSI was substantially reduced in iron-deficient cells. This could be related with the important decline on cytochrome c6 content observed in these cells. Iron deficiency also induced a marked increase in light sensitivity in P. tricornutum cells. A drastic increase in the level of peroxidation of chloroplast lipids was detected in iron-deficient cells even when grown under standard conditions at low light intensity. Illumination with a light intensity of 300 μE m-2 s-1 during different time periods caused a dramatic disappearance in TL signal in cells grown under low iron concentration, this treatment not affecting to the signal in iron-replete cells. The results of this work suggest that iron deficiency induces partial blocking of the electron transfer between PSII and PSI, due to a lower concentration of the electron donor cytochrome c6. This decreased electron transfer may induce the over-reduction of the plastoquinone pool and consequently the appearance of acceptor side photoinhibition in PSII even at low light intensities. The functionality of chlororespiratory electron transfer pathway under iron restricted conditions is also discussed. PMID:27536301

Ultrasound assessment of hamstring muscle size using posterior thigh muscle thickness.

PubMed

Abe, Takashi; Loenneke, Jeremy P; Thiebaud, Robert S

2016-05-01

Several studies have investigated the relationship between ultrasound-measured muscle thickness (MT) and individual muscle cross-sectional area (CSA) and muscle volume (MV) in extremity and trunk muscles; however, the hamstring muscle has not been studied. The purpose of this study was to examine the relationship between posterior thigh MT by ultrasound and the muscle CSA and MV of the hamstring obtained by magnetic resonance imaging (MRI). Ten young women aged 20-31 had MT measured by ultrasound at three sites on the medial anterior (50% of thigh length; TL) and posterior (50% and 70% of TL) aspects of the thigh. On the same day, a series of continuous muscle CSA along the thigh was measured by MRI. In each slice, the anatomical CSA of the hamstring (biceps femoris, semitendinosus and semimembranosus) and quadriceps muscle was analysed, and the CSAs at 50% and 70% of TL and maximal CSA of the hamstring (CSAmax ) were determined. MV was calculated by multiplying CSA by slice thickness. A significant correlation was observed between posterior 50% MT and 50% hamstring CSA (r = 0·848, P = 0·002) and between posterior 70% MT and 70% hamstring CSA (r = 0·679, P = 0·031). Posterior 50% MT (r = 0·732, P = 0·016) and 50% MTxTL (r = 0·873, P = 0·001) were also correlated to hamstring MV. Anterior:posterior 50% thigh MT ratio was correlated to MV ratio of quadriceps and hamstring muscles (r = 0·803, P = 0·005). Our results suggest that posterior thigh MT reflects hamstring muscle CSA and MV. The anterior:posterior MT ratio may serve as a surrogate for MV ratio of quadriceps and hamstring. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Thallium isotope variations in anthropogenically-affected soils

NASA Astrophysics Data System (ADS)

Vanek, Ales; Chrastny, Vladislav; Penizek, Vit; Mihaljevic, Martin; Komarek, Michael; Cabala, Jerzy

2014-05-01

Our preliminary data from soils impacted by long-term Tl deposition in the vicinity of a primary/secondary Zn smelter at Olkusz (Poland) indicate apparent variability of ɛ205Tl within soil profiles. The identified ɛ205Tl values presented for the forest soil profile reached -1.7 in the surface/organic horizon, +1.9 in the organo-mineral horizon (Ap), and +1.0 in the mineral horizon (C). This finding suggests both the enrichment of 203Tl isotope in the topsoil, as well as its preferential release during smelting operations, as "lighter" Tl tends to enter the emissions during a high-temperature process. The maximum ɛ205Tl value in the subsurface horizon Ap is in accordance with the concentration peak of oxalate-extractable Mn, indicating the presence of amorphous/poorly-crystalline Mn oxides with a potential to isotopically fractionate Tl toward the "heavier" fraction. The Tl isotope signature in the bottom horizon probably reflects the composition of a local geochemical anomaly of Tl. However, a portion of mobile (anthropogenic) Tl with negative ɛ205Tl moving downwards in the soil profile cannot be neglected. In general, there is no detailed information about the biogeochemical cycling and variations of Tl isotopes in areas affected by significant anthropogenic inputs of the metal (e.g., coal burning and primary metallurgy); the questions of the degree to which the factors such as soil (and sediment) chemistry, mineralogy, local biota, and pollution source control Tl isotope fractionation remain unresolved. Therefore, further research on the topic is needed before any principal conclusions will be made.

Mathematical Constraints on the Use of Transmission Line Models for Simulating Initial Breakdown Pulses in Lightning Discharges

NASA Astrophysics Data System (ADS)

da Silva, C. L.; Merrill, R. A.; Pasko, V. P.

2015-12-01

A significant portion of the in-cloud lightning development is observed as a series of initial breakdown pulses (IBPs) that are characterized by an abrupt change in the electric field at a remote sensor. Recent experimental and theoretical studies have attributed this process to the stepwise elongation of an initial lightning leader inside the thunderstorm [da Silva and Pasko, JGR, 120, 4989-5009, 2015, and references therein]. Attempts to visually observe these events are hampered due to the fact that clouds are opaque to optical radiation. Due to this reason, throughout the last decade, a number of researchers have used the so-called transmission line models (also commonly referred to as engineering models), widely employed for return stroke simulations, to simulate the waveshapes of IBPs, and also of narrow bipolar events. The transmission line (TL) model approach is to prescribe the source current dynamics in a certain manner to match the measured E-field change waveform, with the purpose of retrieving key information about the source, such as its height, peak current, size, speed of charge motion, etc. Although the TL matching method is not necessarily physics-driven, the estimated source characteristics can give insights on the dominant length- and time-scales, as well as, on the energetics of the source. This contributes to better understanding of the environment where the onset and early stages of lightning development takes place.In the present work, we use numerical modeling to constrain the number of source parameters that can be confidently inferred from the observed far-field IBP waveforms. We compare different modified TL models (i.e., with different attenuation behaviors) to show that they tend to produce similar waveforms in conditions where the channel is short. We also demonstrate that it is impossible to simultaneously retrieve the speed of source current propagation and channel length from an observed IBP waveform, in contrast to what has been previously done in the literature. Finally, we demonstrate that the simulated field-to-current conversion factor in IBP sources can vary by more than one order of magnitude, making peak current estimates for intracloud lightning processes a challenging task.

Equations for estimating synthetic unit-hydrograph parameter values for small watersheds in Lake County, Illinois

USGS Publications Warehouse

Melching, C.S.; Marquardt, J.S.

1997-01-01

Design hydrographs computed from design storms, simple models of abstractions (interception, depression storage, and infiltration), and synthetic unit hydrographs provide vital information for stormwater, flood-plain, and water-resources management throughout the United States. Rainfall and runoff data for small watersheds in Lake County collected between 1990 and 1995 were studied to develop equations for estimation of synthetic unit-hydrograph parameters on the basis of watershed and storm characteristics. The synthetic unit-hydrograph parameters of interest were the time of concentration (TC) and watershed-storage coefficient (R) for the Clark unit-hydrograph method, the unit-graph lag (UL) for the Soil Conservation Service (now known as the Natural Resources Conservation Service) dimensionless unit hydrograph, and the hydrograph-time lag (TL) for the linear-reservoir method for unit-hydrograph estimation. Data from 66 storms with effective-precipitation depths greater than 0.4 inches on 9 small watersheds (areas between 0.06 and 37 square miles (mi2)) were utilized to develop the estimation equations, and data from 11 storms on 8 of these watersheds were utilized to verify (test) the estimation equations. The synthetic unit-hydrograph parameters were determined by calibration using the U.S. Army Corps of Engineers Flood Hydrograph Package HEC-1 (TC, R, and UL) or by manual analysis of the rainfall and run-off data (TL). The relation between synthetic unit-hydrograph parameters, and watershed and storm characteristics was determined by multiple linear regression of the logarithms of the parameters and characteristics. Separate sets of equations were developed with watershed area and main channel length as the starting parameters. Percentage of impervious cover, main channel slope, and depth of effective precipitation also were identified as important characteristics for estimation of synthetic unit-hydrograph parameters. The estimation equations utilizing area had multiple correlation coefficients of 0.873, 0.961, 0.968, and 0.963 for TC, R, UL, and TL, respectively, and the estimation equations utilizing main channel length had multiple correlation coefficients of 0.845, 0.957, 0.961, and 0.963 for TC, R, UL, and TL, respectively. Simulation of the measured hydrographs for the verification storms utilizing TC and R obtained from the estimation equations yielded good results without calibration. The peak discharge for 8 of the 11 storms was estimated within 25 percent and the time-to-peak discharge for 10 of the 11 storms was estimated within 20 percent. Thus, application of the estimation equations to determine synthetic unit-hydrograph parameters for design-storm simulation may result in reliable design hydrographs; as long as the physical characteristics of the watersheds under consideration are within the range of those for the watersheds in this study (area: 0.06-37 mi2, main channel length: 0.33-16.6 miles, main channel slope: 3.13-55.3 feet per mile, and percentage of impervious cover: 7.32-40.6 percent). The estimation equations are most reliable when applied to watersheds with areas less than 25 mi2.

Vehicular crash tests of a nested Thrie beam transition barrier.

DOT National Transportation Integrated Search

2002-05-01

In order to comply with a federal mandate, the California Department of Transportation initiated a project : to develop a bridge rail transition design that met NCHRP Report 350 test level 4 (TL-4) criteria. During the : project a total of three tran...

Thallium contamination in arable soils and vegetables around a steel plant-A newly-found significant source of Tl pollution in South China.

PubMed

Liu, Juan; Luo, Xuwen; Wang, Jin; Xiao, Tangfu; Chen, Diyun; Sheng, Guodong; Yin, Meiling; Lippold, Holger; Wang, Chunlin; Chen, Yongheng

2017-05-01

Thallium (Tl) is a highly toxic rare element. Severe Tl poisoning can cause neurological brain damage or even death. The present study was designed to investigate contents of Tl and other associated heavy metals in arable soils and twelve common vegetables cultivated around a steel plant in South China, a newly-found initiator of Tl pollution. Potential health risks of these metals to exposed population via consumption of vegetables were examined by calculating hazard quotients (HQ). The soils showed a significant contamination with Tl at a mean concentration of 1.34 mg/kg. The Tl levels in most vegetables (such as leaf lettuce, chard and pak choy) surpassed the maximum permissible level (0.5 mg/kg) according to the environmental quality standards for food in Germany. Vegetables like leaf lettuce, chard, pak choy, romaine lettuce and Indian beans all exhibited bioconcentration factors (BCF) and transfer factors (TF) for Tl higher than 1, indicating a hyperaccumulation of Tl in these plants. Although the elevated Tl levels in the vegetables at present will not immediately pose significant non-carcinogenic health risks to residents, it highlights the necessity of a permanent monitoring of Tl contamination in the steel-making areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phase-dependent phytoavailability of thallium--a synthetic soil experiment.

PubMed

Vaněk, Aleš; Mihaljevič, Martin; Galušková, Ivana; Chrastný, Vladislav; Komárek, Michael; Penížek, Vít; Zádorová, Tereza; Drábek, Ondřej

2013-04-15

The study deals with the environmental stability of Tl-modified phases (ferrihydrite, goethite, birnessite, calcite and illite) and phytoavailability of Tl in synthetically prepared soils used in a model vegetation experiment. The data presented here clearly demonstrate a strong relationship between the mineralogical position of Tl in the model soil and its uptake by the plant (Sinapis alba L.). The maximum rate of Tl uptake was observed for plants grown on soil containing Tl-modified illite. In contrast, soil enriched in Ksat-birnessite had the lowest potential for Tl release and phytoaccumulation. Root-induced dissolution of synthetic calcite and ferrihydrite in the rhizosphere followed by Tl mobilization was detected. Highly crystalline goethite was more stable in the rhizosphere, compared to ferrihydrite, leading to reduced biological uptake of Tl. Based on the results obtained, the mineralogical aspect must be taken into account prior to general environmental recommendations in areas affected by Tl. Copyright © 2013 Elsevier B.V. All rights reserved.

Investigating the origins of double photopeaks in CsI:Tl samples through activator mapping

NASA Astrophysics Data System (ADS)

Onken, Drew R.; Gridin, Sergii; Williams, Richard T.; Williams, Charles B.; Donati, George L.; Gayshan, Vadim; Vasyukov, Sergey; Gektin, Alex

2018-06-01

Careful examination of the origins of double photopeaks in CsI:Tl provides a foundation for exploring the relationship between activator homogeneity and photopeak resolution in scintillators. In rare cases, certain CsI:Tl crystals exhibit a second photopeak in the pulse-height spectrum. A combination of optical mapping and ICP-MS measurements reveals the presence of two distinct regions with differing Tl concentrations in these crystals. The oscillator strength of the 299 nm absorption A-band of Tl in CsI was measured to be 0.0526 ± 0.0008; this parameter can be used to quantify activator concentration from the optical absorption. Using published measurements of luminescence intensity versus Tl concentration, the distributions of Tl measured from optical absorption maps of the samples were reconstructed into photopeaks in good agreement with experiment. The distribution of Tl concentrations in these particular crystals allowed examining luminescence pulse shape as a function of Tl concentration.

Lone pair effect, structural distortions, and potential for superconductivity in Tl perovskites.

PubMed

Schoop, Leslie M; Müchler, Lukas; Felser, Claudia; Cava, R J

2013-05-06

Drawing the analogy to BaBiO3, we investigate via ab initio electronic structure calculations potential new superconductors of the type ATlX3 with A = Rb and Cs and X = F, Cl, and Br, with a particular emphasis on RbTlCl3. On the basis of chemical reasoning, supported by the calculations, we show that Tl-based perovskites have structural and charge instabilities driven by the lone pair effect, similar to the case of BaBiO3, effectively becoming A2Tl(+)Tl(3+)X6. We find that upon hole doping of RbTlCl3, structures without Tl(+) and Tl(3+) charge disproportionation become more stable, although the ideal cubic perovskite, often viewed as the best host for superconductivity, should not be the most stable phase in the system. The known superconductor (Sr,K)BiO3 and hole doped RbTlCl3, predicted to be most stable in the same tetragonal structure, display highly analogous calculated electronic band structures.

Evaluation of [(201)Tl](III) Vancomycin in normal rats.

PubMed

Jalilian, Amir Reza; Hosseini, Mohammad Amin; Majdabadi, Abbas; Saddadi, Fariba

2008-01-01

Tl-201 has potential in the preparation of radiolabelled compounds similar to its homologues, like In-111 and radiogallium. In this paper, recently prepared [(201)Tl](III) vancomycin complex ([(201)Tl](III)VAN) has been evaluated for its biological properties. [(201)Tl](III)VAN was prepared according to the optimized conditions followed by biodistribution studies in normal rats for up to 52 h. The Staphylococcus aurous specific binding was checked in vitro. The complex was finally injected to normal rats. Tracer SPECT images were obtained in normal animals and compared to those of (67)Ga-citrate. Freshly-prepared [(201)Tl](III)VAN batches (radiochemical yield > 99%, radiochemical purity > 98%, specific activity approximately 1.2 Ci/mmol) showed a similar biodistribution to that of unlabeled vancomycin. The microorganism binding ratios were 3 and 9 for tracer (201)Tl(3+) and tracer (201)Tl(III)DTPA, respectively, suggesting the preservation of the tracer bioactivity. As a nonspecific cell penetrating tracer, [(201)Tl](III)DTPA was used.

Indirect radioimmunoassay for thymus leukemia (TL) antigens. [Mice, /sup 125/I tracer technique

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

Esmon, N.L.; Little, J.R.

1976-09-01

An indirect radioimmunoassay for thymus leukemia TL antigens has been developed and its specificity documented. The assay makes use of anti-TL antibodies produced in congenic mice (A-Tla/sup b/) and radioiodinated purified rabbit anti-mouse IgG. Using this assay, differences can be detected in the amounts of antigen expressed on thymocytes of the three known phenotypes (TL.1,2,3; TL.2; TL/sup -/) of inbred mouse strains. Significant differences are also detected in comparison of the thymocytes from homozygous TL.1,2,3 mice (A-Tla/sup a/) and heterozygotes from Tla/sup a/ and Tla/sup b/ parents. Optimum conditions for the assay have been established. Its ability to detect antigensmore » on glutaraldehyde-fixed cells and the binding of noncytolytic antibodies on both viable and fixed cells are documented. The assay has also been used to quantitate the changes in TL antigen expression on cells incubated in anti-TL antisera under conditions of antigenic modulation.« less

Thallium as a tracer of fluid-rock interaction in the shallow Mariana forearc

NASA Astrophysics Data System (ADS)

Nielsen, Sune G.; Klein, Frieder; Kading, Tristan; Blusztajn, Jerzy; Wickham, Katie

2015-11-01

Fluids driven off the subducting Pacific plate infiltrate the shallow Mariana forearc and lead to extensive serpentinization of mantle peridotite. However, the sources, pathways, and chemical modifications of ascending, slab-derived fluids remain poorly constrained and controversial. In this study, we use thallium (Tl) concentrations and isotopic ratios of serpentinized peridotite and rodingitized diabase from the South Chamorro and Conical Seamounts to discriminate between potential fluid sources with distinct Tl isotope compositions. Serpentinite samples from the Mariana forearc all display ε205 Tl > - 0.5 (where ε205 Tl = 10 , 000 × (205Tl /Tl203sample -205Tl /SRM 997 203Tl ) / (205Tl / SRM 997 203Tl )), which is significantly enriched in 205Tl compared to the normal mantle (ε205 Tl = - 2). Given that high temperature hydrothermal processes do not impart significant Tl isotope fractionation, the isotope compositions of the serpentinites must reflect that of the serpentinizing fluid. Pelagic sediments are the only known slab component that consistently displays ε205 Tl > - 0.5 and, therefore, we interpret the heavy Tl isotope signatures as signifying that the serpentinizing fluids were derived from subducting pelagic sediments. A rodingitized diabase from Conical Seamount was found to have an ε205 Tl of 0.8, suggesting that sediment-sourced serpentinization fluids could also affect diabase and other mafic lithologies in the shallow Mariana forearc. Forearc rodingitization of diabase led to a strong depletion in Tl content and a virtually complete loss of K, Na and Rb. The chemical composition of hybrid fluids resulting from serpentinization of harzburgite with concomitant rodingitization of diabase can be highly alkaline, depleted in Si, yet enriched in Ca, Na, K, and Rb, which is consistent with the composition of fluids emanating from mud volcanoes in the Mariana forearc. Our study suggests that fluid-rock interactions between sedimentary, mafic, and ultramafic lithologies are strongly interconnected even in the shallowest parts of subduction zones. We conclude that transfer of fluids and dissolved elements at temperatures and pressures below 400 °C and 1 GPa, respectively, must be taken into account when elemental budgets and mass transfer between the subducting plate, the forearc, the deep mantle and the ocean are evaluated.

Sizes of prey consumed by two pelagic predators in US reservoirs: Implications for quantifying biomass of available prey

USGS Publications Warehouse

Dennerline, D.E.; Van Den Avyle, M.J.

2000-01-01

Striped bass Morone saxatilis and hybrid bass M. saxatilis x M. chrysops have been stocked to establish fisheries in many US reservoirs, but success has been limited by a poor understanding of relations between prey biomass and predator growth and survival. To define sizes of prey that are morphologically available, we developed predictive relationships between predator length, mouth dimensions, and expected maximum prey size; predictions were then validated using published data on sizes of clupeid prey (Dorosoma spp.) in five US reservoirs. Further, we compared the biomass of prey considered available to predators using two forms of a length-based consumption model - a previously published AP/P ratio and a revised model based on our results. Predictions of maximum prey size using predator GW were consistent with observed prey sizes in US reservoirs. Length of consumed Dorosoma was significantly, but weakly, correlated with predator length in four of the five reservoirs (r2 = 0.006-0.336, P 150 mm TL) were abundant. (C) 2000 Elsevier Science B.V.

Transformational leadership and workplace injury and absenteeism: analysis of a National Nursing Assistant Survey.

PubMed

Lee, Doohee; Coustasse, Alberto; Sikula, Andrew

2011-01-01

Transformational leadership (TL) has long been popular among management scholars and health services researchers, but no research studies have empirically tested the association of TL with workplace injuries and absenteeism among nursing assistants (NAs). This cross-sectional study seeks to explore whether TL is associated with workplace injuries and absenteeism among NAs. We analyzed the 2004 National Nursing Assistant Survey data (n = 2,882). A multivariate logistic regression analysis was performed to test the role of TL in the context of workplace performances. Results reveal that the TL model was positively linked to workplace injury in the level of NAs. Injury-related absenteeism was also associated with the TL style, indicating that TL behaviors may help address workplace absence among NAs. Findings suggest that introducing TL practices may benefit NAs in improving workplace performances.

Health risks of thallium in contaminated arable soils and food crops irrigated with wastewater from a sulfuric acid plant in western Guangdong province, China.

PubMed

Wang, Chunlin; Chen, Yongheng; Liu, Juan; Wang, Jin; Li, Xiangping; Zhang, Yongbo; Liu, Yimin

2013-04-01

Thallium (Tl) contamination in soils poses a significant threat to human health due to the high toxicity of Tl and its ready assimilation by crops. Consumption of food crops contaminated with Tl is a major food chain route for human exposure. The health risks of Tl in contaminated food crops irrigated with wastewater from a sulfuric acid factory were investigated in this paper. Results indicate that long-term Tl-containing wastewater irrigation resulted in Tl contamination of arable soils and crops. The pollution load index values indicated that the arable soils were moderately enriched with Tl. Tl was highly accumulated in the crops. The content of Tl in the edible plant portions of crops ranged from 1.2 mg/kg to 104.8 mg/kg, exceeding the recommended permissible limits for food crops. The daily intake of metals (DIM) values of Tl for both adults and children via the consumption of the food crops except soya beans were higher than the reference oral dose (RfD) limit recommend by the United States environmental protection agency (US-EPA). Health risk index (HRI) values were generally higher than 1, indicating that health risks associated with Tl exposure are significant and assumed to be dangerous to the health of local villagers. Therefore, much attention should be paid to avoid consumption of these Tl-contaminated crops that can cause great potential risks. Copyright © 2012 Elsevier Inc. All rights reserved.

A Total Quality Leadership Process Improvement Model

DTIC Science & Technology

1993-12-01

Leadership Process Improvement Model by Archester Houston, Ph.D. and Steven L. Dockstader, Ph.D. DTICS ELECTE tleaese oand sale itsFeat ben proe 94-12058...tTl ’AND SIATE COVERID0 Z lits Z40 uerI’Ll12/93 IFinalS.FNR IM F A Total Quality Leadership Process Improvement Model M ARRhOW~ Archester Houston, Ph.D...and Steven L. Dockstader, Ph.D. ?. 7PEJORMING ORG-AN1:AION NAMEIS) AND 00-RESS(ES) L PERFORMIN4 ORAINIZATION Total Quality Leadership OfficeREOTNMR

Fabrication and chemical composition of RF magnetron sputtered Tl-Ca-Ba-Cu-O high Tc superconducting thin films

NASA Technical Reports Server (NTRS)

Subramanyam, G.; Radpour, F.; Kapoor, V. J.; Lemon, G. H.

1990-01-01

The preparation of TlCaBaCuO superconducting thin films on (100) SrTiO3 substrates is described, and the results of their characterization are presented. Sintering and annealing the thin films in a Tl-rich ambient yielded superconductivity with a Tc of 107 K. The results of an XPS study support two possible mechanisms for the creation of holes in the TlCaBaCuO compound: (1) partial substitution of Ca(2+) for Tl(3+), resulting in hole creation, and (2) charge transfer from Tl(3+) to the CuO layers, resulting in a Tl valence between +3 and +1.

Ab initio calculations of the electron spectrum and density of states of TlFeS{sub 2} and TlFeSe{sub 2} crystals

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

Ismayilova, N. A., E-mail: ismayilova-narmin-84@mail.ru; Orudjev, H. S.; Jabarov, S. H.

2017-04-15

The results of ab initio calculations of the electron spectrum of TlFeS{sub 2} and TlFeSe{sub 2} crystals in the antiferromagnetic phase are reported. Calculations are carried out in the context of the density functional theory. The origin of the bands of s, p, and d electron states of Tl, Fe, S, and Se atoms is studied. It is established that, in the antiferromagnetic phase, the crystals possess semiconductor properties. The band gaps are found to be 0.05 and 0.34 eV for TlFeS{sub 2} and TlFeSe{sub 2} crystals, respectively.

Being Ethically Minded: Practising the Scholarship of Teaching and Learning in an Ethical Manner

ERIC Educational Resources Information Center

Healey, Ruth L.; Bass, Tina; Caulfield, Jay; Hoffman, Adam; McGinn, Michelle K.; Miller-Young, Janice; Haigh, Martin

2013-01-01

The authors propose a working definition of ethical Scholarship of Teaching and Learning (SoTL), advance an ethical framework for SoTL inquiry, and present a case study that illustrates the complexity of ethical issues in SoTL. The Ethical SoTL Matrix is a flexible framework designed to support SoTL practitioners, particularly in the formative…

Thermoluminescence and Antarctic meteorites

NASA Technical Reports Server (NTRS)

Sears, D. W. G.; Hasan, F. A.

1986-01-01

The level of natural thermoluminescence (TL) in meteorites is the result of competition between build-up, due to exposure to cosmic radiation, and thermal decay. Antarctic meteorites tend to have lower natural TL than non-Antarctic meteorites because of their generally larger terrestrial ages. However, since a few observed falls have low TL due to a recent heating event, such as passage within approximately 0.7 astronomical units of the Sun, this could also be the case for some Antarctic meteorites. Dose rate variations due to shielding, heating during atmospheric passage, and anomalous fading also cause natural TL variations, but the effects are either relatively small, occur infrequently, or can be experimentally circumvented. The TL sensitivity of meteorites reflects the abundance and nature of the feldspar. Thus intense shock, which destroys feldspar, causes the TL sensitivity to decrease by 1 to 2 orders of magnitude, while metamorphism, which generates feldspar through the devitrification of glass, causes TL sensitivity to increase by a factor of approximately 10000. The TL-metamorphism relationship is particularly strong for the lowest levels of metamorphism. The order-disorder transformation in feldspar also affect the TL emission characteristics and thus TL provides a means of paleothermometry.

Modulation of thymus-leukemia antigens on mouse leukemia cells induced by IgG, but not IgM, antibody.

PubMed

Stackpole, C W

1980-04-01

Exposure of mouse leukemia cells bearing thymus-leukemia (TL) surface antigens to whole TL alloantiserum has previously been shown to desensitize the cells to subsequent lysis by guinea pig complement (C) and fresh antiserum (antigenic modulation) and to correlate with the ability of cells to escape immune destruction in mice immunized against TL antigens. Tested in vitro, IgG of TL.1,2,3,5 antiserum modulated RADA1 leukemia cells (TL.1,2,3,5) completely within 2 hours at 37 degrees C when fully sensitizing amounts were used, with normal mouse serum as a source of C3. Similar results were obtained with IgG1, IgG2a, and IgG2b fractions of TL antiserum. An IgG2a monoclonal TL.3 antibody also completely modulated TL.3 antigens and partially modulated all antigens detected with TL.1,2,3,5 antiserum. IgM anti-TL.1,2,3,5 failed to modulate RADA1 cells even after 6 hours in vitro when fully sensitizing amounts of antibody were used. An IgM monoclonal TL antibody also failed to induce modulation. Modulation did occur on cells incubated with fully sensitizing amounts of IgG and IgM TL.1,2,3,5 antibody simultaneously, and nearly all cell-bound immunoglobulins were IgG. In mice passively immunized with IgG TL antibody, RADA1 cells modulated completely within 24 hours, whereas no modulation occurred during 4 days in mice immunized with IgM antibody. However, in both instances, tumor cells grew actively, which indicated that tumor escape did not depend on achievement of a modulated state.

Performance of parasitological and molecular techniques for the diagnosis and surveillance of gambiense sleeping sickness.

PubMed

Mumba Ngoyi, Dieudonné; Ali Ekangu, Rosine; Mumvemba Kodi, Marie France; Pyana, Patient Pati; Balharbi, Fatima; Decq, Mélanie; Kande Betu, Victor; Van der Veken, Wim; Sese, Claude; Menten, Joris; Büscher, Philippe; Lejon, Veerle

2014-06-01

Recently, improvements have been made to diagnostics for gambiense sleeping sickness control but their performance remains poorly documented and may depend on specimen processing prior to examination. In a prospective study in the Democratic Republic of the Congo, we compared the diagnostic performance of several parasite detection techniques, immune trypanolysis and of m18S PCR on whole blood stored in a stabilisation buffer or dried on filter paper. Individuals with CATT whole blood (WB) titer ≥1∶4 or with clinical signs indicative for sleeping sickness were examined for presence of trypanosomes in lymph node aspirate (LNA) and/or in blood. Blood was examined with Capillary Centrifugation Technique (CTC), mini-Anion Exchange Centrifugation Technique (mAECT) and mAECT on buffy coat (BC). PCR was performed on whole blood (i) stored in guanidine hydrochloride EDTA (GE) stabilisation buffer and (ii) dried on filter paper, and repeatability and reproducibility were assessed. Immune trypanolysis (TL) was performed on plasma. A total of 237 persons were included. Among 143 parasitologically confirmed cases, 85.3% had a CATT-WB titre of ≥1/8, 39.2% were positive in LNA, 47.5% in CTC, 80.4% in mAECT-WB, 90.9% in mAECT-BC, 95.1% in TL and up to 89.5% in PCR on GE-stabilised blood. PCR on GE-stabilised blood showed highest repeatability (87.8%) and inter-laboratory reproducibility (86.9%). Of the 94 non-confirmed suspects, respectively 39.4% and 23.4% were TL or PCR positive. Suboptimal specificity of PCR and TL was also suggested by latent class analysis. The combination of LNA examination with mAECT-BC offered excellent diagnostic sensitivity. For PCR, storage of blood in stabilisation buffer is to be preferred over filter paper. TL as well as PCR are useful for remote diagnosis but are not more sensitive than mAECT-BC. For TL and PCR, the specificity, and thus usefulness for management of non-confirmed suspects remain to be determined.

Performance of Parasitological and Molecular Techniques for the Diagnosis and Surveillance of Gambiense Sleeping Sickness

PubMed Central

Mumba Ngoyi, Dieudonné; Ali Ekangu, Rosine; Mumvemba Kodi, Marie France; Pyana, Patient Pati; Balharbi, Fatima; Decq, Mélanie; Kande Betu, Victor; Van der Veken, Wim; Sese, Claude; Menten, Joris; Büscher, Philippe; Lejon, Veerle

2014-01-01

Objectives Recently, improvements have been made to diagnostics for gambiense sleeping sickness control but their performance remains poorly documented and may depend on specimen processing prior to examination. In a prospective study in the Democratic Republic of the Congo, we compared the diagnostic performance of several parasite detection techniques, immune trypanolysis and of m18S PCR on whole blood stored in a stabilisation buffer or dried on filter paper. Methods Individuals with CATT whole blood (WB) titer ≥1∶4 or with clinical signs indicative for sleeping sickness were examined for presence of trypanosomes in lymph node aspirate (LNA) and/or in blood. Blood was examined with Capillary Centrifugation Technique (CTC), mini-Anion Exchange Centrifugation Technique (mAECT) and mAECT on buffy coat (BC). PCR was performed on whole blood (i) stored in guanidine hydrochloride EDTA (GE) stabilisation buffer and (ii) dried on filter paper, and repeatability and reproducibility were assessed. Immune trypanolysis (TL) was performed on plasma. Results A total of 237 persons were included. Among 143 parasitologically confirmed cases, 85.3% had a CATT-WB titre of ≥1/8, 39.2% were positive in LNA, 47.5% in CTC, 80.4% in mAECT-WB, 90.9% in mAECT-BC, 95.1% in TL and up to 89.5% in PCR on GE-stabilised blood. PCR on GE-stabilised blood showed highest repeatability (87.8%) and inter-laboratory reproducibility (86.9%). Of the 94 non-confirmed suspects, respectively 39.4% and 23.4% were TL or PCR positive. Suboptimal specificity of PCR and TL was also suggested by latent class analysis. Conclusion The combination of LNA examination with mAECT-BC offered excellent diagnostic sensitivity. For PCR, storage of blood in stabilisation buffer is to be preferred over filter paper. TL as well as PCR are useful for remote diagnosis but are not more sensitive than mAECT-BC. For TL and PCR, the specificity, and thus usefulness for management of non-confirmed suspects remain to be determined. PMID:24921941

An Investigation of the Impact of Guessing on Coefficient α and Reliability

PubMed Central

2014-01-01

Guessing is known to influence the test reliability of multiple-choice tests. Although there are many studies that have examined the impact of guessing, they used rather restrictive assumptions (e.g., parallel test assumptions, homogeneous inter-item correlations, homogeneous item difficulty, and homogeneous guessing levels across items) to evaluate the relation between guessing and test reliability. Based on the item response theory (IRT) framework, this study investigated the extent of the impact of guessing on reliability under more realistic conditions where item difficulty, item discrimination, and guessing levels actually vary across items with three different test lengths (TL). By accommodating multiple item characteristics simultaneously, this study also focused on examining interaction effects between guessing and other variables entered in the simulation to be more realistic. The simulation of the more realistic conditions and calculations of reliability and classical test theory (CTT) item statistics were facilitated by expressing CTT item statistics, coefficient α, and reliability in terms of IRT model parameters. In addition to the general negative impact of guessing on reliability, results showed interaction effects between TL and guessing and between guessing and test difficulty.

Environmental influences on the seasonal distribution of Vibrio parahaemolyticus in the Pacific Northwest of the USA

EPA Science Inventory

Populations of Vibrio parahaemolyticus in the environment can be influenced by numerous factors. We assessed the correlation of total (tl+) and potentially virulent (tdh+) V. parahaemolyticus in water with three harmful algal bloom (HAB) genera (Pseudo-nitzschia, Alexandrium and ...

Genetic toxicology of thallium: a review.

PubMed

Rodríguez-Mercado, Juan José; Altamirano-Lozano, Mario Agustín

2013-07-01

This review summarizes the current knowledge about the general toxicity of thallium (Tl) and its environmental sources, with special emphasis placed on its potential mutagenic, genotoxic, and cytotoxic effects on both eukaryotic and prokaryotic cells. Tl is a nonessential heavy metal that poses environmental and occupational threats as well as therapeutic hazards because of its use in medicine. It is found in two oxidation states, thallous (Tl(+)) and thallic (Tl(3+)), both of which are considered highly toxic to human beings and domestic and wild organisms. Many Tl compounds are colorless, odorless and tasteless, and these characteristics, combined with the high toxicity of TI compounds, have led to their use as poisons. Because of its similarity to potassium ions (K(+)), plants and mammals readily absorb Tl(+) through the skin and digestive and respiratory systems. In mammals, it can cross the placental, hematoencephalic, and gonadal barriers. Inside cells, Tl can accumulate and interfere with the metabolism of potassium and other metal cations, mimicking or inhibiting their action. The effects of Tl on genetic material have not yet been thoroughly explored, and few existing studies have focused exclusively on Tl(+). Both in vivo and in vitro studies indicate that Tl compounds can have a weak mutagenic effect, but no definitive effect on the induction of primary DNA damage or chromosomal damage has been shown. These studies have demonstrated that Tl compounds are highly toxic and lead to changes in cell-cycle progression.

Auger compositional depth profiling of the metal contact-TlBr interface

NASA Astrophysics Data System (ADS)

Nelson, A. J.; Swanberg, E. L.; Voss, L. F.; Graff, R. T.; Conway, A. M.; Nikolic, R. J.; Payne, S. A.; Kim, H.; Cirignano, L.; Shah, K.

2015-08-01

Degradation of room temperature operation of TlBr radiation detectors with time is thought to be due to electromigration of Tl and Br vacancies within the crystal as well as the metal contacts migrating into the TlBr crystal itself due to electrochemical reactions at the metal/TlBr interface. Scanning Auger electron spectroscopy (AES) in combination with sputter depth profiling was used to investigate the metal contact surface/interfacial structure on TlBr devices. Device-grade TlBr was polished and subjected to a 32% HCl etch to remove surface damage and create a TlBr1-xClx surface layer prior to metal contact deposition. Auger compositional depth profiling results reveal non-equilibrium interfacial diffusion after device operation in both air and N2 at ambient temperature. These results improve our understanding of contact/device degradation versus operating environment for further enhancing radiation detector performance.

Thermoluminescence analysis can identify irradiated ingredient in soy sauce before and after pasteurization

NASA Astrophysics Data System (ADS)

Lee, Jeong-Eun; Sanyal, Bhaskar; Akram, Kashif; Jo, Yunhee; Baek, Ji-Yeong; Kwon, Joong-Ho

2017-05-01

Thermoluminescence (TL) analysis was conducted to identify small quantities (0.5%, 1%, and 1.5%) of γ ray-or electron beam-irradiated garlic powder in a soy sauce after commercial pasteurization. The sauce samples with γ ray- and electron beam-irradiated (0, 1 or 10 kGy) garlic powder showed detectable TL glow curves, characterized by radiation-induced maximum in the temperature range of 180-225 °C. The successful identification of soy sauces with an irradiation history was dependent on both the mixing ratio of the irradiated ingredient and the irradiation dose. Post-irradiation pasteurization (85 °C, 30 min) caused no considerable changes in TL glow shape or intensity. Interlaboratory tests demonstrated that the shape and intensity of the first TL glow curve (TL1) could be a better detection marker than a TL ratio (TL1/TL2).

50 CFR 622.37 - Size limits.

Code of Federal Regulations, 2014 CFR

2014-10-01

....38 (b)(3) and 13 inches (33.0 cm), TL, for a fish taken by a person not subject to the bag limit. (2) Lane snapper—8 inches (20.3 cm), TL. (3) Vermilion snapper—10 inches (25.4 cm), TL. (4) Cubera, gray... in § 622.38(b)(2)—20 inches (50.8 cm), TL. (3) Scamp—16 inches (40.6 cm), TL. (4) Yellowfin grouper...

50 CFR 622.37 - Size limits.

Code of Federal Regulations, 2013 CFR

2013-10-01

....38 (b)(3) and 13 inches (33.0 cm), TL, for a fish taken by a person not subject to the bag limit. (2) Lane snapper—8 inches (20.3 cm), TL. (3) Vermilion snapper—10 inches (25.4 cm), TL. (4) Cubera, gray... in § 622.38(b)(2)—20 inches (50.8 cm), TL. (3) Scamp—16 inches (40.6 cm), TL. (4) Yellowfin grouper...

Thallium isotope evidence for a permanent increase in marine organic carbon export in the early Eocene

USGS Publications Warehouse

Nielsen, S.G.; Mar-Gerrison, S.; Gannoun, A.; LaRowe, D.; Klemm, V.; Halliday, A.N.; Burton, K.W.; Hein, J.R.

2009-01-01

The first high resolution thallium (Tl) isotope records in two ferromanganese crusts (Fe-Mn crusts), CD29 and D11 from the Pacific Ocean are presented. The crusts record pronounced but systematic changes in 205Tl/203Tl that are unlikely to reflect diagenetic overprinting or changes in isotope fractionation between seawater and Fe-Mn crusts. It appears more likely that the Fe-Mn crusts track the Tl isotope composition of seawater over time. The present-day oceanic residence time of Tl is estimated to be about 20,000??yr, such that the isotopic composition should reflect ocean-wide events. New and published Os isotope data are used to construct age models for these crusts that are consistent with each other and significantly different from previous age models. Application of these age models reveals that the Tl isotope composition of seawater changed systematically between ~ 55??Ma and ~ 45??Ma. Using a simple box model it is shown that the present day Tl isotope composition of seawater depends almost exclusively on the ratio between the two principal output fluxes of marine Tl. These fluxes are the rate of removal of Tl from seawater via scavenging by authigenic Fe-Mn oxyhydroxide precipitation and the uptake rate of Tl during low temperature alteration of oceanic crust. It is highly unlikely that the latter has changed greatly. Therefore, assuming that the marine Tl budget has also not changed significantly during the Cenozoic, the low 205Tl/203Tl during the Paleocene is best explained by a more than four-fold higher sequestration of Tl by Fe-Mn oxyhydroxides compared with at the present day. The calculated Cenozoic Tl isotopic seawater curve displays a striking similarity to that of S, providing evidence that both systems may have responded to the same change in the marine environment. A plausible explanation is a marked and permanent increase in organic carbon export from ~ 55??Ma to ~ 45??Ma, which led to higher pyrite burial rates and a significantly reduced flux of Fe-Mn oxide removal as a result of increased biological uptake of Fe and Mn. ?? 2008 Elsevier B.V. All rights reserved.

Development of europium doped BaSO4 TL OSL dual phosphor for radiation dosimetry applications

NASA Astrophysics Data System (ADS)

Patle, Anita; Patil, R. R.; Kulkarni, M. S.; Bhatt, B. C.; Moharil, S. V.

2015-08-01

This paper presents the results on the preparation and characterization of Europium-doped Barium sulfate (BaSO4: Eu) TL /OSL dual phosphor. The OSL sensitivity was found to be 11% of the commercially available Al2O3: C, using area integration method. The sample also shows good TL sensitivity and the dosimetric peak appears around 190°C with a shoulder at 282°C. After OSL readout, No change in the TL glow curve is observed. Since the observed TL peaks are not responsible for the observed OSL, good OSL as well as TL sensitivity and low fading will make this phosphor suitable for applications in radiation dosimetry using OSL as well as TL.

Marine mammal impacts in exploited ecosystems: would large scale culling benefit fisheries?

PubMed

Morissette, Lyne; Christensen, Villy; Pauly, Daniel

2012-01-01

Competition between marine mammals and fisheries for marine resources-whether real or perceived-has become a major issue for several countries and in international fora. We examined trophic interactions between marine mammals and fisheries based on a resource overlap index, using seven Ecopath models including marine mammal groups. On a global scale, most food consumed by marine mammals consisted of prey types that were not the main target of fisheries. For each ecosystem, the primary production required (PPR) to sustain marine mammals was less than half the PPR to sustain fisheries catches. We also developed an index representing the mean trophic level of marine mammal's consumption (TL(Q)) and compared it with the mean trophic level of fisheries' catches (TL(C)). Our results showed that overall TL(Q) was lower than TL(C) (2.88 versus 3.42). As fisheries increasingly exploit lower-trophic level species, the competition with marine mammals may become more important. We used mixed trophic impact analysis to evaluate indirect trophic effects of marine mammals, and in some cases found beneficial effects on some prey. Finally, we assessed the change in the trophic structure of an ecosystem after a simulated extirpation of marine mammal populations. We found that this lead to alterations in the structure of the ecosystems, and that there was no clear and direct relationship between marine mammals' predation and the potential catch by fisheries. Indeed, total biomass, with no marine mammals in the ecosystem, generally remained surprisingly similar, or even decreased for some species.

[Tl(III)(dota)](-): An Extraordinarily Robust Macrocyclic Complex.

PubMed

Fodor, Tamás; Bányai, István; Bényei, Attila; Platas-Iglesias, Carlos; Purgel, Mihály; Horváth, Gábor L; Zékány, László; Tircsó, Gyula; Tóth, Imre

2015-06-01

The X-ray structure of {C(NH2)3}[Tl(dota)]·H2O shows that the Tl(3+) ion is deeply buried in the macrocyclic cavity of the dota(4-) ligand (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate) with average Tl-N and Tl-O distances of 2.464 and 2.365 Å, respectively. The metal ion is directly coordinated to the eight donor atoms of the ligand, which results in a twisted square antiprismatic (TSAP') coordination around Tl(3+). A multinuclear (1)H, (13)C, and (205)Tl NMR study combined with DFT calculations confirmed the TSAP' structure of the complex in aqueous solution, which exists as the Λ(λλλλ)/Δ(δδδδ) enantiomeric pair. (205)Tl NMR spectroscopy allowed the protonation constant associated with the protonation of the complex according to [Tl(dota)](-) + H(+) ⇆ [Tl(Hdota)] to be determined, which turned out to be pK(H)Tl(dota) = 1.4 ± 0.1. [Tl(dota)](-) does not react with Br(-), even when using an excess of the anion, but it forms a weak mixed complex with cyanide, [Tl(dota)](-) + CN(-) ⇆ [Tl(dota)(CN)](2-), with an equilibrium constant of Kmix = 6.0 ± 0.8. The dissociation of the [Tl(dota)](-) complex was determined by UV-vis spectrophotometry under acidic conditions using a large excess of Br(-), and it was found to follow proton-assisted kinetics and to take place very slowly (∼10 days), even in 1 M HClO4, with the estimated half-life of the process being in the 10(9) h range at neutral pH. The solution dynamics of [Tl(dota)](-) were investigated using (13)C NMR spectroscopy and DFT calculations. The (13)C NMR spectra recorded at low temperature (272 K) point to C4 symmetry of the complex in solution, which averages to C4v as the temperature increases. This dynamic behavior was attributed to the Λ(λλλλ) ↔ Δ(δδδδ) enantiomerization process, which involves both the inversion of the macrocyclic unit and the rotation of the pendant arms. According to our calculations, the arm-rotation process limits the Λ(λλλλ) ↔ Δ(δδδδ) interconversion.

Timing Performance of TlBr Detectors

NASA Astrophysics Data System (ADS)

Hitomi, Keitaro; Tada, Tsutomu; Onodera, Toshiyuki; Shoji, Tadayoshi; Kim, Seong-Yun; Xu, Yuanlai; Ishii, Keizo

2013-08-01

The timing performance of TlBr detectors was evaluated at room temperature (22 °C). 0.5-mm-thick planar TlBr detectors with Tl circular electrodes with a diameter of 3 mm were fabricated from TlBr crystals grown by the traveling molten zone method using a zone-purified material. The pulse rise time of the TlBr detector was measured using a digital oscilloscope as the cathode surface of the device was irradiated with a 22Na gamma-ray source. Coincidence timing spectra were obtained between the TlBr detector and a BaF2 scintillation detector when both detectors were irradiated with 511 keV positron annihilation gamma-rays. The timing resolution of the TlBr detector was found to be inversely proportional to the applied bias voltage. The TlBr detector, in coincidence with the BaF2 detector, exhibited timing resolutions characterized by a 6.5 ns full width at half maximum (FWHM) and an 8.5 ns FWHM with and without an energy window of 350 keV-560 keV, respectively.

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

Tl sub 1-x Pr sub x Sr sub 2-y Pr sub y CuO sub 5-. delta. : First member of the family TlA sub 2 Ca sub m-1 Cu sub m O sub 2m+3 (A = Ba, Sr)

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

Bourgault, D.; Martin, C.; Michel, C.

1989-02-01

The synthesis, structure, and superconducting properties of the first member obtained during the investigation of the Tl-Sr-Cu-O and Tl-Sr-Pr-Cu-O systems are described. In order to check out the structural model corresponding to the first member of the series, TlSr{sub 2}Ca{sub m-1}Cu{sub m}O{sub 2m+3}, structure calculations were performed from x-ray powder data of the oxide Tl{sub 0.8}Sr{sub 1.6}Pr{sub 0.6}CuO{sub 5}. Magnetic measurements show only traces of diamagnetism for Tl{sub 0.7}Pr{sub 0.3}Sr{sub 2}CuO{sub 5-{delta}} and TlSr{sub 2}CuO{sub 5-{delta}}; however, Tl{sub 0.8}Pr{sub 0.6}Sr{sub 1.6}Cu{sub 5-{delta}} exhibits diamagnetism below 40K. 21 refs., 2 figs.

Time-Loss and Non–Time-Loss Injuries in Youth Football Players

PubMed Central

Dompier, Thomas P; Powell, John W; Barron, Mary J; Moore, Marguerite T

2007-01-01

Context: Estimates suggest that more than 5.5 million youths play football annually, and 28% of youth football players (age range = 5 to 14 years) are injured each year, resulting in more than 187 000 emergency room visits. Objective: To analyze time-loss (TL) and non–time-loss (NTL) injury patterns across age groups in youth football players. Design: Two-year observational cohort. Setting: Two midwestern communities, including players from the fourth through eighth grades and between the ages of 9 and 14 years. Patients or Other Participants: A total of 779 players participated, including 296 in grades 4 and 5; 203 in grade 6; 188 in grade 7; and 92 in grade 8. (Players in the fourth and fifth grades participated on the same teams, so we considered them as a single group.) Main Outcome Measure(s): Injury frequencies and exposures were collected by certified athletic trainers present at each practice and game and used to calculate injury rates with 95% confidence intervals (CIs) for both TL and NTL injuries across age groups. Results: A total of 474 injuries and 26 565 exposures were identified. Injuries were reported by 36.5% of the players, with 14.4% reporting more than 1 injury in a season. The overall injury rate per 1000 athlete-exposures (A-Es) was 17.8 (95% CI = 16.3, 19.5). The injury rate increased with each succeeding grade from 14.3 per 1000 A-Es (95% CI = 12.1, 16.9) in grades 4 and 5 to 21.7 per 1000 A-Es (95% CI = 17.2, 27.3) in grade 8. A total of 58.6% of all injuries were NTL. Non–time-loss injuries accounted for 70.1% of the injuries reported by fourth and fifth graders, 55.1% by sixth graders, 64.0% by seventh graders, and 33.8% by eighth graders. The cumulative NTL injury rate was 10.5 per 1000 A-Es (95% CI = 9.3, 11.8), and the TL injury rate was 7.4 per 1000 A-Es (95% CI = 6.4, 8.5). Conclusions: Youth football players sustained more NTL injuries than TL injuries. We recommend that a first-aid–certified coach or league official be present at all games and practices. PMID:18059996

Advances in TlBr detector development

NASA Astrophysics Data System (ADS)

Hitomi, Keitaro; Shoji, Tadayoshi; Ishii, Keizo

2013-09-01

Thallium bromide (TlBr) is a promising compound semiconductor for fabrication of gamma-ray detectors. The attractive physical properties of TlBr lie in its high photon stopping power, high resistivity and good charge transport properties. Gamma-ray detectors fabricated from TlBr crystals have exhibited excellent spectroscopic performance. In this paper, advances in TlBr radiation detector development are reviewed with emphasis on crystal growth, detector fabrication, physical properties and detector performance.

Continued development of room temperature semiconductor nuclear detectors

NASA Astrophysics Data System (ADS)

Kim, Hadong; Cirignano, Leonard; Churilov, Alexei; Ciampi, Guido; Kargar, Alireza; Higgins, William; O'Dougherty, Patrick; Kim, Suyoung; Squillante, Michael R.; Shah, Kanai

2010-08-01

Thallium bromide (TlBr) and related ternary compounds, TlBrI and TlBrCl, have been under development for room temperature gamma ray spectroscopy due to several promising properties. Due to recent advances in material processing, electron mobility-lifetime product of TlBr is close to Cd(Zn)Te's value which allowed us to fabricate large working detectors. We were also able to fabricate and obtain spectroscopic results from TlBr Capacitive Frisch Grid detector and orthogonal strip detectors. In this paper we report on our recent TlBr and related ternary detector results and preliminary results from Cinnabar (HgS) detectors.