bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving reptile ecological risk assessment: Oral and dermal toxicity of pesticides to a common lizard species (Sceloporus occidentalis)
Authors: Weir Scott M. , Yu Shuangying , Talent Larry G. , Maul Jonathan D. , Anderson Todd A. , Salice Christopher J. 
Published: March 2015

Abstract

Reptiles have been understudied in ecotoxicology, which limits consideration in ecological risk assessments. The goals of the present study were 3-fold: to improve oral and dermal dosing methodologies for reptiles, to generate reptile toxicity data for pesticides, and to correlate reptile and avian toxicity. The authors first assessed the toxicity of different dosing vehicles: 100 μL of water, propylene glycol, and acetone were not toxic. The authors then assessed the oral and dermal toxicity of 4 pesticides following the up-and-down procedure. Neither brodifacoum nor chlorothalonil caused mortality at doses ≤ 1750 μg/g. Under the “neat pesticide” oral exposure, endosulfan (median lethal dose [LD50] = 9.8 μg/g) was more toxic than λ-cyhalothrin (LD50 = 916.5 μg/g). Neither chemical was toxic via dermal exposure. An acetone dosing vehicle increased λ-cyhalothrin toxicity (oral LD50 = 9.8 μg/g; dermal LD50 = 17.5 μg/g), but not endosulfan. Finally, changes in dosing method and husbandry significantly increased dermal λ-cyhalothrin LD50s, which highlights the importance of standardized methods. The authors combined data from the present study with other reptile LD50s to correlate with available avian data. When only definitive LD50s were used in the analysis, a strong correlation was found between avian and reptile toxicity. The results suggest it is possible to build predictive relationships between avian and reptile LD50s. More research is needed, however, to understand trends associated with chemical classes and modes of action. Environ Toxicol Chem 2015;34:1778–1786. © 2015 SETAC
Copper and nickel partitioning with nanoscale goethite under variable aquatic conditions
Authors: Danner Kelsey M. , Hammerschmidt Chad R. , Costello David M. , Burton G. Allen 
Published: March 2015

Abstract

Metal contaminated sediments can be toxic to aquatic organisms and are common in human-dominated ecosystems, which results in metals being a leading cause of ecosystem impairment. Bioavailability of metals is influenced by their affinity for dissolved and solid-phase ligands, including iron (Fe) oxyhydroxides, which have been hypothesized to reduce metal toxicity in sediments. The authors examined the adsorption kinetics of copper (Cu) and nickel (Ni) with goethite (α-FeOOH) and characterized the influences of solute metal concentration, pH, ionic strength, and humate concentration on steady-state partitioning of the metals with goethite under conditions representative of natural aquatic environments. Copper and Ni readily adsorbed to goethite, and steady-state partitioning was achieved within 2 h. Although ionic strength had no effect on metal partitioning, adsorption of Cu and Ni to goethite was enhanced by alkaline pH and reduced by competition with humate. Because distribution coefficient (KD) values for Cu and Ni from the present study are comparable to values measured in natural systems, the authors hypothesize that goethite may contribute significantly to the adsorption of both Ni and Cu to particles in the environment. The authors suggest that incorporating binding by Fe oxides in metal bioavailability models should be a priority for improving risk assessment of metal-contaminated oxic sediments. Environ Toxicol Chem 2015;34:1705–1710. © 2015 SETAC
Proteomics analysis of Xenopus laevis gonad tissue following chronic exposure to atrazine
Authors: Chen Xiuping , Wang Jiamei , Zhu Haojun , Ding Jiatong , Peng Yufa 
Published: March 2015

Abstract

Atrazine is the most commonly detected pesticide contaminant in ground and surface water. Previous studies have shown that atrazine is an endocrine disruptor owing to its adverse effects on the male reproductive system in several vertebrates, but very few molecular mechanisms for these effects have been revealed. In the present study, Xenopus laevis were exposed to 100 ppb of atrazine for 120 d, and then the isobaric tags for relative and absolute quantitation (iTRAQ) technique was used to detect global changes in protein profiles of the testes and ovaries. The results showed that 100 ppb of atrazine exposure adversely affected the growth of X. laevis and did not induce hermaphroditism but delayed or prevented the development of male seminiferous tubules. Proteomic analysis showed that atrazine altered expression of 143 and 121 proteins in the testes and ovaries, respectively, and most of them are involved in cellular and metabolic processes and biological regulation based on their biological processes. In addition, apoptosis, tight junctions, and metabolic pathways were significantly altered in the atrazine-treated gonads. Based on the above results, it is postulated that the reproductive toxicity of atrazine may be the result of disruption of tight junctions and metabolic signaling pathways and/or induction of apoptosis in germ cells. Environ Toxicol Chem 2015;34:1770–1777. © 2015 SETAC
Implicit LES of free and wall‐bounded turbulent flows based on the discontinuous Galerkin/symmetric interior penalty method
Authors: de Wiart C. Carton , Hillewaert K. , Bricteux L. , Winckelmans G. 
Published: March 2015

SummaryThis paper presents the second validation step of a compressible discontinuous Galerkin solver with symmetric interior penalty (DGM/SIP) for the direct numerical simulation (DNS) and the large eddy simulation (LES) of complex flows. The method has already been successfully validated for DNS of an academic flow and has been applied to flows around complex geometries (e.g. airfoils and turbomachinery blades). During these studies, the advantages of the dissipation properties of the method have been highlighted, showing a natural tendency to dissipate only the under‐resolved scales (i.e the smallest scales present on the mesh), leaving the larger scales unaffected. This phenomenon is further enhanced as the polynomial order is increased. Indeed, the order increases the dissipation at the largest wave numbers, while its range of impact is reduced. These properties are spectrally compatible with a subgrid‐scale model, and hence DGM may be well suited to be used for an implicit LES (ILES) approach. A validation of this DGM/ILES approach is here investigated on canonical flows, allowing to study the impact of the discretisation on the turbulence for under‐resolved computations. The first test case is the LES of decaying homogeneous isotropic turbulence (HIT) at very high Reynolds number. This benchmark allows to assess the spectral behaviour of the method for implicit LES. The results are in agreement with theory and are even slightly more accurate than other numerical results from literature, obtained using a pseudo‐spectral (PS) method with a state‐of‐the‐art subgrid‐scale model. The second benchmark is the LES of the channel flow. Three Reynolds numbers are considered: Reτ=395, 590 and 950. The results are compared with DNS of Moser et al. and Hoyas et al., also using PS methods. Both averaged velocity and fluctuations are globally in good agreement with the reference, showing the ability of the method to predict equilibrium wall‐bounded flow turbulence. To show that the method is able to perform accurate DNS, a DNS of HIT at Reλ=64 and a DNS of the channel flow at Reτ=180 are also performed. The effects of the grid refinement are investigated on the channel flow at Reτ=395, highlighting the improvement of the results when refining the mesh in the spanwise direction. Finally, the modification of the ILES parameters, that is the Riemann solver and of the SIP coefficient, is studied on both cases, showing a significant influence on the choice of the Riemann solver. Copyright © 2015 John Wiley & Sons, Ltd.
Family Structure and Long‐Term Care Insurance Purchase
Authors: Van Houtven Courtney Harold , Coe Norma B. , Konetzka R. Tamara 
Published: March 2015

AbstractWhile it has long been assumed that family structure and potential sources of informal care play a large role in the purchase decisions for long‐term care insurance (LTCI), current empirical evidence is inconclusive. Our study examines the relationship between family structure and LTCI purchase and addresses several major limitations of the prior literature by using a long panel of data and considering modern family relationships, such as the presence of stepchildren. We find that family structure characteristics from one's own generation, particularly about one's spouse, are associated with purchase, but that few family structure attributes from the younger generation have an influence. Family factors that may indicate future caregiver supply are negatively associated with purchase: having a coresidential child, signaling close proximity, and having a currently working spouse, signaling a healthy and able spouse, that long‐term care planning has not occurred yet or that there is less need for asset protection afforded by LTCI. Dynamic factors, such as increasing wealth or turning 65, are associated with higher likelihood of LTCI purchase. Copyright © 2015 John Wiley & Sons, Ltd.
The Effect of Free Personal Care for the Elderly on Informal Caregiving
Authors: Karlsberg Schaffer Sarah 
Published: March 2015

AbstractPopulation forecasters have predicted that the proportion of people in the UK aged 65 years and older will rise significantly in coming decades. This shift in demographics will put increasing pressure on the National Health Service and providers of social care. However, older people do not rely only on care provided by the state; informal care of the elderly is often supplied by family and friends. Therefore, the relationship between formal and informal care and the reaction of informal carers to institutional changes is an important policy issue. This study uses individual level data from the British Household Panel Survey to estimate the effects of the introduction of free personal care for the elderly in Scotland on informal care behaviour. As the change in policy applied only to Scotland, a natural experiment is formed allowing a difference‐in‐differences approach to be used. This paper finds that the introduction of the policy increased the probability of women supplying informal care by around six percentage points. In addition, for both sexes, it reports evidence of a shift away from the upper and lower tails towards the middle of the hours of care distribution as a result of the change in policy. Copyright © 2015 John Wiley & Sons, Ltd.
Crowding Out of Long‐Term Care Insurance: Evidence from European Expectations Data
Authors: Costa‐Font Joan , Courbage Christophe 
Published: March 2015

SummaryLong‐term care (LTC) is the largest insurable risk that old‐age individuals face in most western societies. However, the demand for LTC insurance is still ostensibly small in comparison with the financial risk. One explanation that has received limited support is that expectations of either ‘public sector funding’ and ‘family support’ crowd out individual incentives to seek insurance. This paper aims to investigate further the aforementioned motivational crowding‐out hypothesis by developing a theoretical model and by drawing on an innovative empirical analysis of representative European survey data containing records on individual expectations of LTC funding sources (including private insurance, social insurance, and the family). The theoretical model predicts that, when informal care is treated as exogenously determined, expectations of both state support and informal care can potentially crowd out LTC insurance expectations, while this is not necessarily the case when informal care is endogenous to insurance, as happens when intra‐family moral hazard is integrated in the insurance decision. We find evidence consistent with the presence of family crowding out but no robust evidence of public sector crowding out. Copyright © 2015 John Wiley & Sons, Ltd.
The Causal Effects of Home Care Use on Institutional Long‐Term Care Utilization and Expenditures
Authors: Guo Jing , Konetzka R. Tamara , Manning Willard G. 
Published: March 2015

AbstractLimited evidence exists on whether expanding home care saves money overall or how much institutional long‐term care can be reduced. This paper estimates the causal effect of Medicaid‐financed home care services on the costs and utilization of institutional long‐term care using Medicaid claims data. A unique instrumental variable was applied to address the potential bias caused by omitted variables or reverse effect of institutional care use. We find that the use of Medicaid‐financed home care services significantly reduced but only partially offset utilization and Medicaid expenditures on nursing facility services. A $1000 increase in Medicaid home care expenditures avoided 2.75 days in nursing facilities and reduced annual Medicaid nursing facility costs by $351 among people over age 65 when selection bias is addressed. Failure to address selection biases would misestimate the substitution and offset effects. Copyright © 2015 John Wiley & Sons, Ltd.
Active and Passive Problem Solving: Moderating Role in the Relation Between Depressive Symptoms and Future Suicidal Ideation Varies by Suicide Attempt History
Authors: Quiñones Victoria , Jurska Justyna , Fener Eileen , Miranda Regina 
Published: March 2015

ObjectiveResearch suggests that being unable to generate solutions to problems in times of distress may contribute to suicidal thoughts and behavior, and that depression is associated with problem‐solving deficits. This study examined active and passive problem solving as moderators of the association between depressive symptoms and future suicidal ideation among suicide attempters and nonattempters.MethodYoung adults (n = 324, 73% female, mean age = 19, standard deviation = 2.22) with (n = 78) and without (n = 246) a suicide attempt history completed a problem‐solving task, self‐report measures of hopelessness, depression, and suicidal ideation at baseline, and a self‐report measure of suicidal ideation at 6‐month follow‐up.ResultsPassive problem solving was higher among suicide attempters but did not moderate the association between depressive symptoms and future suicidal ideation. Among attempters, active problem solving buffered against depressive symptoms in predicting future suicidal ideation.ConclusionsSuicide prevention should foster active problem solving, especially among suicide attempters.
The dependence of efficiency of transmembrane molecular transfer using electroporation on medium viscosity
Authors: Sungailaitė Sandra , Ruzgys Paulius , Šatkauskienė Ingrida , Čepurnienė Karolina , Šatkauskas Saulius 
Published: March 2015

AbstractBackgroundIn the present study, we aimed to evaluate the efficiency of drug and gene electrotransfer into cells in vitro depending on medium viscosity.MethodsExperiments were performed using Chinese hamster ovary cells. Efficiency of molecular electrotransfer depending of medium viscosity was evaluated using two different electroporation conditions: a high‐voltage (HV) pulse and a combination of a high‐voltage pulse and a low‐voltage pulse (HV + LV). To evaluate the efficiency of molecular electrotransfer, anticancer drug bleomycin and two different plasmids coding for green fluorescent protein and luciferase were used.ResultsWe found that a slight increase in medium viscosity from 1.3–1.4 mPa·s significantly decreased the transfection efficiency, both in terms of transfected cells and total protein production, which was abolished completely with an increase in medium viscosity to 6.1 mPa·s. Notably, at this medium viscosity, electrotransfer of the small anticancer drug was still efficient. Using HV and HV + LV pulse combinations, we showed that a decrease of DNA electrotransfer, especially at lower medium viscosities, can be compensated for by the LV pulse to some extent. On the other hand, the addition of the LV pulse after the HV pulse did not have any positive effect on the efficiency of bleomycin electrotransfer.ConclusionsThese findings demonstrate that transfection is very susceptible to medium viscosity and highlights the importance of the electrophoretic component in experiments when a considerable transfection level is needed. Copyright © 2015 John Wiley & Sons, Ltd.
Glycosaminoglycan chemical exchange saturation transfer of lumbar intervertebral discs in patients with spondyloarthritis
Authors: Schleich Christoph , Müller‐Lutz Anja , Matuschke Felix , Sewerin Philipp , Sengewein Ruben , Schmitt Benjamin , Ostendorf Benedikt , Wittsack Hans‐Jörg , Stanke Karolin , Antoch Gerald , Miese Falk 
Published: March 2015

PurposeTo assess glycosaminoglycan (GAG) content of lumbar intervertebral discs (IVD) in patients with spondyloarthritis (SpA) using glycosaminoglycan chemical exchange saturation transfer (gagCEST).Materials and MethodsNinety lumbar intervertebral discs of nine patients with SpA and nine age‐matched healthy controls (eight patients with ankylosing spondylitis; one patient with spondylitis related to inflammatory bowel disease; mean age: 44.1 ± 14.0 years; range: 27–72 years) were examined with a 3T magnetic resonance imaging (MRI) scanner in this prospective study. The MRI protocol included standard morphological, sagittal T2‐weighted (T2w) images to assess Pfirrmann score of the five lumbar IVDs (L1 to S1) and biochemical imaging with gagCEST to calculate a region of interest analysis of nucleus pulposus (NP) and annulus fibrosus (AF). Prior to statistical testing of gagCEST effects (MTRasym values in percent) in patients and controls, IVDs were classified according to the Pfirrmann score.ResultsSignificantly lower gagCEST values of NP and AF were found in SpA patients compared with healthy volunteers (NP: 1.41% ± 0.41%, P = 0.001; 95% confidence interval, CI [0.600%–2.226%]; AF: 1.19% ± 0.32%, P < 0.001; CI [0.560%–1.822%]) by comparing the differences of the means. Pooled nondegenerative IVDs (Pfirrmann 1 and 2) had significantly lower gagCEST effects in patients suffering from SpA compared with healthy controls in NP (P < 0.001; CI [1.176%–2.337%]) and AF (P < 0.001; CI [0.858%–1.779%]). No significant difference of MTRasym values was found in degenerative IVDs between patients and controls in NP (P = 0.204; CI [–0.504%–2.170%]).ConclusionGagCEST analysis of morphologically nondegenerative IVDs (Pfirrmann score 1 and 2) in T2w images demonstrated significantly lower GAG values in patients with spondyloarthritis in NP and AF, possibly representing a depletion of GAG in spondyloarthritis in the absence of morphologic degeneration.J. Magn. Reson. Imaging 2015. J. Magn. Reson. Imaging 2015;42:1057–1063.
Simulating activities of daily living with finite element analysis improves fracture prediction for patients with metastatic femoral lesions
Authors: Goodheart Jacklyn R. , Cleary Richard J. , Damron Timothy A. , Mann Kenneth A. 
Published: March 2015

ABSTRACTPredicting fracture risk for patients with metastatic femoral lesions remains an important clinical problem. Mirels' criterion remains the most formalized radiographic scoring system with good sensitivity (correctly identifying clinical fractures) but relatively poor specificity (correctly identify cases that do not fracture). A series of patients with metastatic femoral lesions had Computed Tomography (CT) scans, were followed prospectively for 4 months, and categorized into fracture (n = 5), non‐fracture (n = 28), or stabilized (n = 11) groups. CT based‐Finite Element (FE) modeling was used to predict fracture for these cases using axial compression (AC), level walking (LW), and aggressive stair ascent (ASA) loading conditions. The FE predicted fracture force was greater for the non‐fracture compared to the fracture group for all loading cases. The ability of the FE models to predict fracture cases (sensitivity) was similar for the groups (Mirels, AC, LW: 80%, ASA: 100%). The ability of the models to correctly predict the non‐fracture cases (specificity) was improved for AC (71%) and LW (86%) loading conditions, when compared to Mirels specificity (43%), but poorer for the ASA (21%) conditions. The results suggest that FE models that assess fracture risk using LW conditions can improve fracture prediction over Mirels scoring in a clinical population. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1226–1234, 2015.
Biomechanical study of ACL reconstruction grafts
Authors: Pailhé Régis , Cavaignac Etienne , Murgier Jérôme , Laffosse Jean‐Michel , Swider Pascal 
Published: March 2015

ABSTRACTThere are no published studies describing the strength quadrupled gracilis tendon alone and quadrupled semitendinosus tendon alone in the configuration used for anterior cruciate ligament (ACL) reconstruction. The primary objective was to compare the mechanical properties of grafts used for ACL reconstruction during a tensile failure test. The secondary objective was to evaluate the effect of uniform suturing on graft strength. Fifteen pairs of knees were used. The mechanical properties of five types of ACL grafts were evaluated: patellar tendon (PT), sutured patellar tendon (sPT), both hamstring tendons (GST4), quadrupled semitendinosus (ST4), and quadrupled gracilis (G4). Validated methods were used to perform the tensile tests to failure and to record the results. Student's t‐test was used to compare the various samples. The maximum load to failure was 630.8N (± 239.1) for the ST4, 473.5N (± 176.9) for the GST4, 413.3N (± 120.4) for the sPT, and 416.4N (± 187.7) for the G4 construct. Only the ST4 had a significantly higher failure load than the other grafts. The sPT had a higher failure load than the PT. The ST4 construct had the highest maximum load to failure of all the ACL graft types in the testing performed here. Uniform suturing of the grafts improved their ability to withstand tensile loading. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1188–1196, 2015.
Synthesis, Characterization, and Ion Sensing Application of Pyrene‐Containing Chemical Probes
Authors: Karagollu Osman , Gorur Mesut , Gode Fethiye , Sennik Busra , Yilmaz Faruk 
Published: March 2015

A novel pyrene‐functionalized thiophene compound (Thi‐Pyr) and pyrene‐functionalized styrene polymers (P7–9) are synthesized via 1,3‐dipolar cycloaddition reaction between the azide functional groups of the precursors and 1‐ethynylpyrene. Glass transition temperature of the styrene polymers increases remarkably upon the covalent attachment of the pyrene unit through triazole linkers, whereas the thermal stabilities of the styrene polymers are not affected by the incorporation of pyrene moieties. Thi‐Pyr exhibits the characteristic pyrene monomer emission bands; on the other hand, P7–9 show the excimer emission bands of pyrene due to the excitation of ground state dimeric species. The monomer emissions of Thi‐Pyr and the excimer emissions of P7–9 are distinguishably increased by the addition of HP2O73−, Cl−, and Br− anions. The responses of Thi‐Pyr and P7–9 to the addition of HP2O73− are stronger than any other anions, indicating their selectivity to HP2O73− anion to some extent.
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