bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors associated with high burden in caregivers of older adults with cancer
Authors: Hsu Tina , Loscalzo Matthew , Ramani Rupal , Forman Stephen , Popplewell Leslie , Clark Karen , Katheria Vani , Feng Tao , Strowbridge Rex , Rinehart Redmond , Smith Dan , Matthews Keith , Dillehunt Jeff , Hurria Arti 
Published: June 2014

BACKGROUNDOlder adults with cancer are vulnerable to functional decline, which places greater onus on caregivers. Few studies have prospectively examined burden in caregivers of older cancer patients. The objective of this study was to determine the factors associated with high caregiver burden.METHODSIn total, 100 caregivers of patients aged ≥65 years with cancer, who were recruited at a single institution, completed questionnaires gauging their perception of the patient's physical, emotional, and social health. The association between these items, cancer‐related factors, sociodemographic factors, and caregiver burden (measured using the Caregiver Strain Index [CSI]) was determined through multivariate analysis.RESULTSThe median patient age was 70 years (range, 65‐91 years), 70% of patients had advanced disease, and 98% were receiving treatment. Caregivers were mostly women (73%), spouses (68%), and lived with the patient (79%). The median amount of care provided was 10 hours per week. The mean CSI score (± standard deviation) was 3.1 ± 3.2. Most caregivers (75%) reported some burden, with 15% reporting high caregiver burden (CSI score, ≥7). In multivariate analysis, employed caregivers (odds ratio, 4.5; 95% confidence interval, 1.1‐18.4; P = .04) and those caring for patients who required more help with instrumental activities of daily living (Older Americans Resources and Services‐Instrumental Activities of Daily Living score, <12 of a possible 14; odds ratio, 12.4; 95% confidence interval, 2.4‐62.5; P < .001) were more likely to experience high caregiver burden (CSI score, ≥7).CONCLUSIONSCaregiver burden is common in those who care for older cancer patients. High burden is more likely in employed caregivers and in those who care for patients who require increased functional assistance. Further studies are needed to determine the unique challenges experienced by caregivers of older adults with cancer and potential interventions to alleviate burden in these caregivers. Cancer 2014;120:2927–2935. © 2014 American Cancer Society.
On the fate of seasonally plastic traits in a rainforest butterfly under relaxed selection
Authors: Oostra Vicencio , Brakefield Paul M. , Hiltemann Yvonne , Zwaan Bas J. , Brattström Oskar 
Published: June 2014

AbstractMany organisms display phenotypic plasticity as adaptation to seasonal environmental fluctuations. Often, such seasonal responses entails plasticity of a whole suite of morphological and life‐history traits that together contribute to the adaptive phenotypes in the alternative environments. While phenotypic plasticity in general is a well‐studied phenomenon, little is known about the evolutionary fate of plastic responses if natural selection on plasticity is relaxed. Here, we study whether the presumed ancestral seasonal plasticity of the rainforest butterfly Bicyclus sanaos (Fabricius, 1793) is still retained despite the fact that this species inhabits an environmentally stable habitat. Being exposed to an atypical range of temperatures in the laboratory revealed hidden reaction norms for several traits, including wing pattern. In contrast, reproductive body allocation has lost the plastic response. In the savannah butterfly, B. anynana (Butler, 1879), these traits show strong developmental plasticity as an adaptation to the contrasting environments of its seasonal habitat and they are coordinated via a common developmental hormonal system. Our results for B. sanaos indicate that such integration of plastic traits – as a result of past selection on expressing a coordinated environmental response – can be broken when the optimal reaction norms for those traits diverge in a new environment.
Mitochondria selective S‐nitrosation by mitochondria‐targeted S‐nitrosothiol protects against post‐infarct heart failure in mouse hearts
Authors: Methner Carmen , Chouchani Edward T. , Buonincontri Guido , Pell Victoria R. , Sawiak Stephen J. , Murphy Michael P. , Krieg Thomas 
Published: June 2014

AimsRecently it has been shown that the mitochondria‐targeted S‐nitrosothiol MitoSNO protects against acute ischaemia/reperfusion (IR) injury by inhibiting the reactivation of mitochondrial complex I in the first minutes of reperfusion of ischaemic tissue, thereby preventing free radical formation that underlies IR injury. However, it remains unclear how this transient inhibition of mitochondrial complex I‐mediated free radicals at reperfusion affects the long‐term recovery of the heart following IR injury. Here we determined whether the acute protection by MitoSNO at reperfusion prevented the subsequent development of post‐myocardial infarction heart failure.Methods and resultsMice were subjected to 30 min left coronary artery occlusion followed by reperfusion and recovery over 28 days. MitoSNO (100 ng/kg) was applied 5 min before the onset of reperfusion followed by 20 min infusion (1 ng/kg/min). Infarct size and cardiac function were measured by magnetic resonance imaging (MRI) 24 h after infarction. MitoSNO‐treated mice exhibited reduced infarct size and preserved function. In addition, MitoSNO at reperfusion improved outcome measures 28 days post‐IR, including preserved systolic function (63.7 ±1.8% LVEF vs. 53.7 ± 2.1% in controls, P = 0.01) and tissue fibrosis.ConclusionsMitoSNO action acutely at reperfusion reduces infarct size and protects from post‐myocardial infarction heart failure. Therefore, targeted inhibition of mitochondrial complex I in the first minutes of reperfusion by MitoSNO is a rational therapeutic strategy for preventing subsequent heart failure in patients undergoing IR injury.
Electronic Origin of Out‐of‐Plane Distortions in Porphyrins
Authors: Austeria Muthu P. , Pancharatna Pattath D. , Balakrishnarajan Musiri M. 
Published: June 2014

AbstractPorphyrins are noninnocent ligands that facilitate redox processes in many biological reactions. Though the porphyrin dianion is planar and aromatic, in many instances, its skeleton exhibits a variety of out‐of‐plane (OOP) distortions, which are primarily attributed to steric factors. Nevertheless, these distortions are suspected to play a hidden role in their biochemical reactions, as the nature of the distortion is conserved for a specific functionality across species. The propensity of porphyrins to assist redox reactions remains mysterious, as oxidation and OOP distortions affect their aromaticity. Our quantum chemical modelling of the two‐electron oxidation of porphyrin reveals that there are definite electronic reasons behind OOP distortions. An extension of the frontier orbital model of Gouterman to include the occupied b1g, b2g and a1g (σ) molecular orbitals (MOs) is necessary to explain the nature and origin of OOP distortions. The distortions are the effect of the mixing of these σ‐type MOs with the π‐type a1u and a2u highest occupied molecular orbitals (HOMOs). These are further facilitated by the flexibility of the internal [16]annulene skeleton of the porphyrin framework. In the absence of transition metal ions, oxidation usually entails pronounced bond alternation along this internal cross owing to a1u/a2u mixing, which leads to the loss of aromaticity. However, this is accompanied by OOP distortions that help to retain the local aromaticity of the pyrrolic rings. Transition metal porphyrins with their energetically accessible d orbitals prefer OOP distortions over bond alternation and effectively conserve aromaticity. For late transition metal ions, the d8 electronic configuration, which is ideal for a square‐planar complex, itself shows a variety of OOP distortions that stabilize the corresponding oxidation state through the mixing of the b1g MO with the a2u MO. For octahedral complexes with d6 configuration of the central metal ion, a two‐electron oxidation is effectively supported by OOP distortions that result from the mixing of the b2g MO with the a2u MO. The a1u MO is usually less prone to mixing as it is concentrated far away from the central metal ion. Despite involving σ–π mixing, these OOP distortions conserve the aromaticity as shown by the computed chemical shifts of the optimized porphyrin systems. In addition to explaining the origin of the noninnocent nature of porphyrins, our results also provides a basis for the rational prediction and control of the OOP distortions to suite the desired biomimetic applications.
Numerical experiments in fire science: a study of ceiling jets
Authors: Johansson Nils , Wahlqvist Jonathan , van Hees Patrick 
Published: June 2014

SummaryIn this paper, a numerical experiment, consisting of 90 simulations in Fire Dynamics Simulator (FDS), is conducted for two different purposes. Firstly, numerical experiments are explored as a research method in fire science, and it is demonstrated that numerical experiments could be used as a complement to traditional fire experiments in fire science research. Secondly, an evaluation of previously derived correlations for ceiling jet excess temperatures and velocities is performed with the help of the results from the numerical experiment. The procedure used in this evaluation constitutes an outline for how a numerical experiment can be conducted in fire science. The evaluation indicates that the existing correlations will give a good estimate of the average temperature in a ceiling jet calculated by FDS. However, the correlations do not give a good estimate of the maximum excess temperature. A new correlation to estimate the maximum temperature has therefor been developed and is presented in the paper. Copyright © 2014 John Wiley & Sons, Ltd.
Evaluation of Hydrogen Crossover through Fuel Cell Membranes
Authors: Schoemaker M. , Misz U. , Beckhaus P. , Heinzel A. 
Published: June 2014

AbstractGas crossover is an unavoidable phenomenon in proton exchange fuel cell membranes. Nitrogen and oxygen from the cathode pass through the membrane to the anode, while hydrogen crosses from the anode to the cathode. The hydrogen crossover leads to a reduction in efficiency due to parasitic hydrogen consumption and mixed potentials on the cathode electrode. Furthermore it causes degradation effects and pinhole formation. Hence the hydrogen crossover represents a fundamental factor for the lifetime of a fuel cell and quantification of the crossover is a key factor for membrane qualification.In this article two in situ electrochemical techniques to evaluate the hydrogen crossover are described, cyclic voltammetry and potential step method. Both methods and the achieved results are compared to each other. Finally the potential step method is applied to evaluate the hydrogen crossover as a function of the anode pressure and the hydrogen permeability coefficients are determined.
Ras‐GRF2 mediates long‐term potentiation, survival, and response to an enriched environment of newborn neurons in the hippocampus
Authors: Darcy Michael J. , Trouche Stéphanie , Jin Shan‐Xue , Feig Larry A. 
Published: June 2014

ABSTRACTHippocampal adult neurogenesis contributes to key functions of the dentate gyrus (DG), including contextual discrimination. This is due, at least in part, to the unique form of plasticity that new neurons display at a specific stage of their development when compared with the surrounding principal neurons. In addition, the contribution that newborn neurons make to dentate function can be enhanced by an increase in their numbers induced by a stimulating environment. However, signaling mechanisms that regulate these properties of newborn neurons are poorly understood. Here, we show that Ras‐GRF2 (GRF2), a calcium‐regulated exchange factor that can activate Ras and Rac GTPases, contributes to both of these properties of newborn neurons. Using Ras‐GRF2 knockout mice and wild‐type mice stereotactically injected with retrovirus containing shRNA against the exchange factor, we demonstrate that GRF2 promotes the survival of newborn neurons of the DG at approximately 1–2 weeks after their birth. GRF2 also controls the distinct form of long‐term potentiation that is characteristic of new neurons of the hippocampus through its effector Erk MAP kinase. Moreover, the enhancement of neuron survival that occurs after mice are exposed to an enriched environment also involves GRF2 function. Consistent with these observations, GRF2 knockout mice display defective contextual discrimination. Overall, these findings indicate that GRF2 regulates both the basal level and environmentally induced increase of newborn neuron survival, as well as in the induction of a distinct form of synaptic plasticity of newborn neurons that contributes to distinct features of hippocampus‐derived learning and memory. © 2014 Wiley Periodicals, Inc.
The testis of greater white‐toothed shrew Crocidura russula in Southern European populations: A case of adaptive lack of seasonal involution?
Authors: Massoud Diaa , Barrionuevo Francisco J. , Ortega Esperanza , Burgos Miguel , Jiménez Rafael 
Published: June 2014

ABSTRACTMales of all seasonal breeding mammals undergo circannual periods of testis involution resulting in almost complete ablation of the germinative epithelium. We performed a morphometric, histological, hormonal, and gene‐expression study of the testes from winter and summer males of the greater white‐toothed shrew, Crocidura russula, in populations of the southeastern Iberian Peninsula. Unexpectedly, we found no significant differences between the two study groups. Surprisingly, female data confirmed a non‐breeding period in the summer, evidencing that males retain full testis function even when most females are not receptive. This situation, which has not been described before, does not occur in northern populations of the same species where, in addition, the reproductive cycle is inverted with respect to those in the south, as the non‐breeding period occurs in winter instead in summer. Considering that the non‐reproductive period shortens at lower latitude locations, we hypothesize that in southern populations the non‐breeding period is short enough to make testis regression inefficient in terms of energy savings, because: (1) testes of C. russula are very small, a condition derived from their monogamy that implies low investment in spermatogenesis; and (2) the spermatogenic cycle of this species is slow and long. The inverted seasonal breeding cycle and the lack of seasonal testis regression described here are new adaptive processes that deserve further research, and provide evidence that the genetic and hormonal mechanisms controlling reproduction timing in mammals are more plastic and versatile than initially suspected. J. Exp. Zool. (Mol. Dev. Evol.) 322B: 304–315, 2014. © 2014 Wiley Periodicals, Inc.
Effect of plant litter addition on element leaching in young sandy soils
Authors: Zönnchen Claudia , Schaaf Wolfgang , Esperschütz Jürgen 
Published: June 2014

AbstractThe knowledge about element leaching and biogeochemical cycles during initial stages of soil development is very limited. Therefore, we studied the effects of parent material characteristics and plant litter addition on element leaching from young sandy soils in a microcosm experiment. Our objective was to evaluate the function of young soils as a source and/or sink for nutrients during initial pedogenesis and to identify main processes which are involved in the initial development of biogeochemical cycles. The main research questions were: (1) How do differences in parent material characteristics affect nutrient leaching?; and (2) How is nutrient leaching of young soils influenced by litter addition of different plant functional groups (e.g., legume and grass species)? Combined treatments of two minimally weathered parent materials (pure sand and loamy sand) with plant litter of two plant species (Lotus corniculatus L. and Calamagrostis epigejos L.) were investigated in a soil column experiment. In addition, control columns with parent material or plant litter only were included. Carbonate weathering as a main source for calcium leaching was induced by the moderately acidic irrigation solution used in the experiment. It was 7.5 fold greater for the loamy sand parent material compared to the pure sand despite lower carbonate contents in the loamy sand. Leaching of K was very low for both parent materials but greater for the loamy sand parent material, likely due to transfer processes from fixed to exchangeable potassium forms in the clay minerals of the loamy sand. Plant litter addition generally increased leaching losses. Carbonate dissolution was intensified by both plant litter types, especially by L. corniculatus, very likely due to H+ released during nitrification of N released from plant litter and an increase in partial pressure of CO2 from microbial respiration. In contrast, K was largely retained in the soils, probably due to fixation by clay minerals and microbial immobilization. Only the pure sand treated with L. corniculatus litter leached K, resulting in 4–6 fold greater leaching losses compared to all other treatments. Nitrogen released from L. corniculatus litter was almost completely nitrified and was nearly doubled as compared to that from C. epigejos, resulting in greater N leaching. The results of our study allow identifying the general function and processes of vegetation patches in young ecosystems formed as a result of initial parent material characteristics and invading vegetation with respect to litter decomposition, soil solution composition, nutrient retention and leaching, and effects on the soil mineral phase. These patterns are not mere additive effects of parent materials plus plant litter, but reflect differences in biogeochemical process intensities and could result in an increasing heterogeneity of soil properties, nutrient availability, and element leaching fluxes with time.
Threshold conditions for a discrete nonautonomous SIRS model
Authors: Zhang Tailei , Liu Junli , Teng Zhidong 
Published: June 2014

AbstractIn this paper, a discrete nonautonomous SIRS epidemic model is studied. The model is constructed by applying a nonstandard finite difference scheme. Under weaker assumptions, the sufficient and necessary conditions on the permanence and strong persistence of the disease and the sufficient condition on the extinction of the disease are established. In order to illustrate our theoretical analysis, some numerical simulations are included in the end. Copyright © 2014 John Wiley & Sons, Ltd.
A four‐node plane parametric element based on quadrilateral area coordinate and its application to coupled solid‐deformation/fluid‐flow simulation for porous geomaterials
Authors: Li Gen 
Published: June 2014

SummaryA four‐node plane parametric element AQGβ6‐I is constructed on the basis of the quadrilateral area coordinate, the generalized conforming principle and the projection technique with a penalty factor β within an interval of 0–1. When β = 0, the element has excellent bending performance. When β = 1, the element can pass patch test strictly; its performance is as good as many famous elements. When β value is between 0 and 1, such as β = 0.5, the element can arrive at a compromise between (relatively) low sensitivity to mesh distortion and perfect convergence. The work provides an illuminating method to alleviate a difficult problem in finite element modelling using the four‐node quadrilateral element, which can pass the strict patch test, but has poor performance in bending dominated problem; on the contrary, it has excellent performance in bending dominated problem but cannot pass the strong patch test.The AQGβ6‐I with the convergence formulation (β = 1) is then applied to coupled solid‐deformation/fluid‐flow simulation for porous geomaterials. The computational examples are carried out to demonstrate that the AQGβ6‐I (β = 1) element is not only stable, reliable and efficient but also of high accuracy. The present study provides a good applicable element for finite element simulations of solid‐deformation/fluid‐flow for porous geomaterials. Copyright © 2014 John Wiley & Sons, Ltd.
Body‐size throughout life and risk of depression in postmenopausal women: Findings from the E3N cohort
Authors: Perquier Florence , Lasfargues Aude , Mesrine Sylvie , Clavel‐Chapelon Françoise , Fagherazzi Guy 
Published: June 2014

ObjectiveTo assess the association of body‐size from childhood to age 40 with depression in postmenopausal French women.MethodsParticipants of the E3N study reported birth characteristics and silhouettes matching theirs at age 8, at puberty, at 20‐25, and 35‐40 years (n = 41,144). Depression was assessed by the Center for Epidemiological Studies Depression Scale and split into new‐onset and recurrent depression according to women's history of psychological disorder. Risks were estimated with multinomial logistic regression models.ResultsLow or high birth weights were associated with risk of depression. A large body‐size at age 8 and a large body‐size over the life‐course were both associated with the risk of new‐onset depression specifically, while women with a large body‐size increase at puberty were at risk of recurrent depression. Largest body‐sizes at 20‐25 or 35‐40 years were associated with both the risk of new‐onset and recurrent depression, especially in normal weight women. However, a lean silhouette at 35‐40 years was associated with the risk of recurrent depression only.ConclusionsWomen with a large body‐size from childhood to adulthood might be at higher risk of new‐onset postmenopausal depression, while leanness in adulthood could be associated with a higher risk of recurrent depression.
Identification of immunogenic proteins of the bacterium Acinetobacter baumannii using a proteomic approach
Authors: Fajardo Bonin Renata , Chapeaurouge Alex , Perales Jonas , da Silva José Godinho , do Nascimento Hilton Jorge , D'Alincourt Carvalho Assef Ana Paula , Moreno Senna José Procópio 
Published: June 2014

PurposeAcinetobacter baumannii is an important opportunistic pathogen that causes pneumoniae, urinary tract infections, and/or septicemia in immunocompromised patients. This pathogen is frequently associated with nosocomial outbreaks worldwide and has become particularly problematic because of its prevalence and resistance patterns to several antibiotics. In the present study, we used an immunoproteome‐based approach to identify immunogenic proteins located on the surface of A. baumannii for the development of a possible immunotherapy against this devastating bacterial infection.Experimental designSera from patients with A. baumannii infections (n = 50) and from a control group of healthy individuals (n = 3) were analyzed for reactivity against A. baumannii outer membrane proteins (OMPs) using Western blot analysis. To identify potential immunogenic proteins in A. baumannii, OMPs were separated by 2DE, and reactive sera from infected patients were randomly selected and divided into two different pools, each containing 15 sera. Finally, MALDI‐TOF/TOF mass spectrometric analysis was employed to identify the corresponding proteins.ResultsThis analysis identified six immunoreactive proteins: OmpA, Omp34kDa, OprC, OprB‐like, OXA‐23, and ferric siderophore receptor protein. Notably, these proteins are highly abundant on the bacterial surface and involved in virulence, antibiotic resistance, and growth.Conclusions and clinical relevanceOur results support the notion that the proteins identified in the present immunoproteome study could serve as antigen candidates for the development of vaccines and passive immunotherapies against A. baumannii infections.