bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frequency dependent responses of neuronal models to oscillatory inputs in current versus voltage clamp
Authors: Rotstein Horacio G. , Nadim Farzan 
Published: January 2019

AbstractAction potential generation in neuron depends on a membrane potential threshold, and therefore on how subthreshold inputs influence this voltage. In oscillatory networks, for example, many neuron types have been shown to produce membrane potential (Vm) resonance: a maximum subthreshold response at a nonzero frequency. Resonance is usually measured by recording Vm in response to a sinusoidal current (Iapp), applied at different frequencies (f), an experimental setting known as current clamp (I-clamp). Several recent studies, however, use the voltage clamp (V-clamp) method to control Vm with a sinusoidal input at different frequencies (Vapp(f)) and measure the total membrane current (Im). The two methods obey systems of differential equations of different dimensionality and, while I-clamp provides a measure of electrical impedance (Z(f) = Vm(f)/Iapp(f)), V-clamp measures admittance (Y (f) = Im(f)/Vapp(f)). We analyze the relationship between these two measurement techniques. We show that, despite different dimensionality, in linear systems the two measures are equivalent: Z = Y−1. However, nonlinear model neurons produce different values for Z and Y−1. In particular, nonlinearities in the voltage equation produce a much larger difference between these two quantities than those in equations of recovery variables that describe activation and inactivation kinetics. Neurons are inherently nonlinear and, notably, with ionic currents that amplify resonance, the voltage clamp technique severely underestimates the current clamp response. We demonstrate this difference experimentally using the PD neurons in the crab stomatogastric ganglion. These findings are instructive for researchers who explore cellular mechanisms of neuronal oscillations.
Competing interactions modulate the activity of Sgs1 during DNA end resection
Authors: Kasaciunaite Kristina , Fettes Fergus , Levikova Maryna , Daldrop Peter , Cejka Petr , Seidel Ralf 
Published: January 2019

AbstractDNA double-strand break repair by homologous recombination employs long-range resection of the 5’ DNA ends at the break points. In Saccharomyces cerevisiae, this process can be performed by the RecQ helicase Sgs1 and the helicase-nuclease Dna2. Though functional interplay has been shown, it remains unclear whether and how the proteins cooperate on the molecular level. Here, we resolved the dynamics of DNA unwinding by Sgs1 at the single molecule level and investigated its regulation by Dna2, the single-stranded DNA binding protein RPA and the Top3-Rmi1 complex. We found that Dna2 modulates the velocity of Sgs1, indicating that during end resection the proteins form a physical complex and couple their activities. Sgs1 unwinds DNA and feeds single-stranded DNA to Dna2 for degradation. RPA is found to regulate the processivity and the affinity of Sgs1 to the DNA fork, while Top3-Rmi1 modulated the velocity of Sgs1. We think that the differential regulation of the Sgs1 activity by its protein partners is important to allow diverse cellular functions of Sgs1 during the maintenance of genome stability.
Sensorimotor functional connectivity in unilateral cerebral palsy: influence of corticospinal tract wiring pattern and clinical correlates
Authors: Simon-Martinez Cristina , Jaspers Ellen , Alaerts Kaat , Ortibus Els , Balsters Joshua , Mailleux Lisa , Blommaert Jeroen , Sleurs Charlotte , Klingels Katrijn , Amant Frédéric , Uyttebroeck Anne , Wenderoth Nicole , Feys Hilde 
Published: January 2019

ABSTRACTIn children with unilateral cerebral palsy (uCP), the corticospinal tract (CST) wiring patterns may differ (contralateral, ipsilateral or bilateral), partially determining motor deficits. However, the impact of such CST wiring on functional connectivity remains unknown. Here, we explored differences in functional connectivity of the resting-state sensorimotor network in 26 uCP with periventricular white matter lesions (mean age (SD): 12.87m (±4.5), CST wiring: 9 contralateral, 9 ipsilateral, 6 bilateral) compared to 60 healthy controls (mean age (SD): 14.54 (±4.8)), and between CST wiring patterns. Functional connectivity from each M1 to three bilateral sensorimotor regions of interest (primary sensory cortex, dorsal and ventral premotor cortex) and the supplementary motor area was compared between groups (healthy controls vs. uCP; and healthy controls vs. each CST wiring group). Results from the seed-to-voxel analyses from bilateral M1 were compared between groups. Additionally, relations with upper limb motor deficits were explored. Aberrant sensorimotor functional connectivity seemed to be CST-dependent rather than specific from all the uCP population: in the dominant hemisphere, the contralateral CST group showed increased connectivity between M1 and premotor cortices, whereas the bilateral CST group showed higher connectivity between M1 and somatosensory association areas. These results suggest that functional connectivity of the sensorimotor network is CST wiring-dependent, although the impact on upper limb function remains unclear.
Nedd4 E3 ligase and beta-arrestins regulate ubiquitination, trafficking, and stability of the mGlu7 receptor
Authors: Lee Sanghyeon , Park Sunha , Lee Hyojin , Han Seulki , Song Jae-man , Han Dohyun , Suh Young Ho 
Published: January 2019

AbstractThe metabotropic glutamate receptor 7 (mGlu7) is a class C G protein-coupled receptor (GPCR) that modulates excitatory neurotransmitter release at the presynaptic active zone. Although post-translational modification of cellular proteins with ubiquitin is a key molecular mechanism governing protein degradation and function, mGlu7 ubiquitination and its functional consequences have not been elucidated yet. Here, we report that Nedd4 ubiquitin E3 ligase and β-arrestins regulate ubiquitination of mGlu7 in heterologous cells and neurons. Upon agonist-stimulation, β-arrestins recruit Nedd4 to mGlu7 and facilitate Nedd4-mediated ubiquitination of mGlu7. Nedd4 and β-arrestins regulate constitutive and agonist-induced endocytosis of mGlu7 and are required for mGlu7-dependent MAPK signaling in neurons. In addition, Nedd4-mediated ubiquitination results in the degradation of mGlu7 by both the lysosomal and proteasomal degradation pathways. These findings provide a model in which Nedd4 and β-arrestin act together as a complex to regulate mGlu7 surface expression and function at the presynaptic terminals.
Spatial Distribution of Breast Cancer in Sudan 2010-2016
Authors: Abdelbagi Elbasheer Marwa Maweya , Alkhidir Ayah Galal Abdelrahman , Awad Mohammed Siham Mohammed , Hassan Abbas Areej Abuelgasim , Mohamed Aisha Osman , Bereir Isra Mahgoub , Abdalazeez Hiba Reyad , Noma Mounkaila 
Published: January 2019

AbstractBackgroundBreast cancer is the most prevalent cancer among females worldwide including Sudan. The aim of this study was to determine the spatial distribution of breast cancer in Sudan.Materials and methodsA facility based cross-sectional study was implemented in eighteen histopathology laboratories distributed in the three localities of Khartoum State on a sample of 4630 Breast Cancer cases diagnosed during the period 2010-2016. A master database was developed through Epi Info™ 7.1.5.2 for computerizing the data collected: the facility name, type (public or private), and its geo- location (latitude and longitude). Personal data on patients were extracted from their respective medical records (name, age, marital status, ethnic group, State, locality, administrative unit, permanent address and phone number, histopathology diagnosis). The data was summarized through SPSS to generate frequency tables for estimating prevalence and the geographical information system (ArcGIS 10.3) was used to generate the epidemiological distribution maps. ArcGIS 10.3 spatial analysis features were used to develop risk maps based on the kriging method.ResultsBreast cancer prevalence was 3.9 cases per 100,000 female populations. Of the 4423 cases of breast cancer, invasive breast carcinoma of no special type (NST) was the most frequent (79.5%, 3517/4423) histopathological diagnosis. The spatial analysis indicated as high risk areas for breast cancer in Sudan the States of Nile River, Northern, Red Sea, White Nile, Northern and Southern Kordofan.ConclusionsThe attempt to develop a predictive map of breast cancer in Sudan revealed three levels of risk areas (risk, intermediate and high risk areas); regardless the risk level, appropriate preventive and curative health interventions with full support from decision makers are urgently needed.
Sarcopenia is an independent predictor of hospitalization in chronic kidney disease outpatients
Authors: Jeong Hye Yun , Ahn Wooyeol , Kim Jun Chul , Choi Yu Bum , Kim Jinkwon , Jun Hak Hoon , Lee Soonchul , Yang Dong Ho , Oh Jisu , Bae Jinkun , Lee So-Young 
Published: January 2019

AbstractBackgroundPatients with chronic kidney disease (CKD) experience much more marked and earlier muscle wasting than subjects who do not have chronic illnesses. However, a few studies that have examined sarcopenia have been reported in CKD patients. We investigated the prevalence of sarcopenia in predialysis and dialysis outpatients with CKD and explored its relationship with the clinical outcomes.MeasurementsSarcopenia was defined as reduced muscle strength accompanied by decreased adjusted appendicular skeletal muscle (ASM), while those patients who exhibited only one of these characteristics were categorized as presarcopenic patients. ASM was measured by bioimpedence analysis, and muscle strength was evaluated by handgrips. ASM was adjusted by weight (ASM/wt). Patients were prospectively followed for up to 2 years.ResultsOne hundred seventy-nine patients were recruited (114 male and 65 female patients who were classified into 103 predialysis patients and 76 dialysis patients, with 44.7% having diabetes). Their mean age was 60.6 ± 13.5 years old. The prevalence of sarcopenia was 9.5%, while 55.9% of the patients were categorized as presarcopenic. The ASM/wt index showed significant correlations with age, handgrip strength, HOMA-IR and frailty scores. Multivariate Cox proportional hazards models demonstrated that the risk of hospitalization was significantly higher for patients with presarcopenia [hazard ratio (HR), 2.48; 95% confidence interval (CI), 1.180–5.230], and the risk of hospitalization was much higher for patients with sarcopenia than for patients in the nonsarcopenic group (HR, 9.11; 95% CI, 2.295–25.182)ConclusionsSarcopenia and presarcopenia, which were defined using the ASM/wt index and handgrip strength, predicted a poorer, hospitalization-free survival in CKD patients
Understanding variation in maternal health service coverage and maternal health outcomes among districts in Rwanda
Authors: Sayinzoga Felix , Moses Tetui , van der Velden Koos , van Dillen Jeroen , Bijlmakers Leon 
Published: January 2019

AbstractObjectiveTo identify factors that explain variations between districts in maternal health service coverage and maternal health outcomes.MethodsIndividual key informant interviews and focus group discussions using structured topic lists were conducted in May 2015 in four purposively selected districts.ResultsThe solidarity support for poor people and the interconnectedness between local leaders and heads of health facilities were identified as enablers of health service utilization. Geographical factors, in particular location close to borders with mobile populations and migrants, and large populations with sparsely distributed health infrastructure, exacerbated by hilly topography and muddy roads were identified as barriers. Shortages of skilled health providers at the level of district hospitals were cited as contributing to poor maternal health outcomes.ConclusionThere is a need to take into account disparities between districts when allocating staff and financial resources in order to achieve universal coverage for high-quality maternal health services and better outcomes. Local innovations such as the use of SMS and WhatsApp text messages by health workers and financial protection schemes for poor patients improve solidarity and are worth to be scaled up.
Depression and Anxiety in Healthcare Staffs in A Tertiary University Hospital in Luoyang, Henan Province: A Cross-Sectional Observational Study
Authors: Wang Hao , Qing Xiaochun , Li Li , Zhang Lijun , Ruan Jing , Niu Xiaohua , Liu Xiaotian , Wu Ruge , Li Jiangbo , Fan Keke , Chang Xuewei , Zhang Mingming , Li Lixia , Zhang Zhuo , Zhang Shouyan 
Published: January 2019

Abstract ObjectiveMental health condition of medical professionals in China is under-recognized. The current study aimed to determine the prevalence of depression and anxiety among healthcare professionals and explore the potential influence factors.MethodThe study employed a cross-sectional design. All employees were surveyed in the first week of September 2017. General information included gender, age, workload, workplace violence, sleep quality and so on. Depression and anxiety were evaluated using PHQ-9 and GAD-7, respectively. SPSS 22.0 was used for data analysis. Logistic regression was conducted to explore risk factors contributed to metal health.ResultsA total of 1,950 questionnaires were delivered, and 1,864 were returned with a response rate of 95.6%. The prevalence of depression and anxiety were 24.1% and 28.9%. As for workload, the average number of beds in charge per month is 65.97±95.58 beds, among which internal medicine department and surgical department endure more workloads. Though workers in ER and ICU manage fewer beds, they bear the longest nonstop working length in the previous month (19.18±10.82 h). There were 78.0% had suffered WPV in the preceding year. Staffs in ER and ICU are at higher risk to physical violence, especially doctors. Regarding to sleep quality, only 9.2% participants reported that they sleep well. Logistic regression indicated that workplace violence and sleep quality were independent risk factors for both anxiety and depression.ConclusionThe current study revealed the devastating conditions of mental disorders in medical workers and associated factors. Effective interventions are necessary to improve this situation.
Diverse stepping motions of cytoplasmic dynein revealed by kinetic modeling
Authors: Kubo Shintaroh , Shima Tomohiro , Takada Shoji 
Published: January 2019

AbstractCytoplasmic dynein is a two-headed molecular motor that moves to the minus end of microtubule (MT) using ATP hydrolysis free energy. By employing its two heads (motor domains), cytoplasmic dynein shows various bipedal stepping motions; the inchworm and hand-over-hand motions, as well as non-alternate steps of one head. However, the molecular basis to achieve such diverse stepping manners remains obscure. Here, we propose a kinetic model for bipedal motions of cytoplasmic dynein and performed Gillespie Monte Carlo simulations that reproduces most experimental data obtained to date. The model represents status of each motor domain as five states according to conformations, nucleotide- and MT-binding conditions of the domain. Also, the relative positions of the two domains were approximated by three discrete states. Accompanied by ATP hydrolysis cycles, the model dynein stochastically and processively moved forward in multiple steps via diverse pathways, including inchworm and hand-over-hand motions, same as experimental data. The model reproduced key experimental motility-related parameters including velocity and run-length as functions of ATP concentration and external force. Our model reveals that, in a typical inchworm motion, the leading domain moves via the ATP-dependent power-stroke of the linker coupled with a small change in the stalk angle, whereas the lagging domain moves via diffusion dragged by the leading domain. Moreover, the hand-over-hand motion in the model dynein clearly differs from that of kinesin by the usage of the power-stroke.Author SummaryCytoplasmic dynein is a two-headed molecular motor, which moves linearly and transports intra-cellar organelles along microtubules driven by ATP hydrolysis free energy. In contrast to other better-known molecular motors, such as kinesin, dynein is known to take various stepping motions including motions akin to human walking and inchworm-like motions. However, molecular mechanisms underpinning the diverse stepping motions are unclear. Here, based on recent high-resolution structure information and single-molecule motility assay data, we designed a kinetic model that explicitly include two heads, each of which makes ATP hydrolysis cycles and moves along the microtubules. Using the model, we performed Monte Carlo simulations. The simulation reproduced most of currently available experimental results. More importantly, the simulation suggested molecular mechanisms of various stepping motions. While stepping motions apparently resemble to those proposed before, once looking into details, we found the resulting mechanisms distinct from previously proposed ones in the usage of ATP and protein conformation changes coupled with stepping motions.
Ethics in social media marketing
Authors: Tsao Wen-Chin , Mau Tz-Chi 
Published: January 2019

Purpose
Consumer-generated online product reviews (OPRs) have become a crucial source of information for consumers; however, OPRs are increasingly being incentivized. The purpose of this paper is to find a method of sponsorship and disclosure that could be considered ethically sound.

Design/methodology/approach
This study adopted a quasi-experimental approach to clarifying how the method of sponsorship impacts reader perceptions of OPRs in terms of helpfulness, credibility and purchase intention. Two experiments were performed on an online platform using data from 480 participants. Hypotheses were tested using analysis of covariance.

Findings
Meaning under the premise that sponsorship information is disclosed and not withheld from the readers, Study 1 revealed that experiential sponsorship is the best sponsorship. Study 2 revealed that featuring reviewers with greater influence in the online community increases the positive influence of disclosing experiential sponsorship on OPR persuasiveness.

Originality/value
The findings in this study provide rational incentives for firms to disclose sponsorship information, i.e. demonstrate high ethical standards in marketing. This was shown to create a win-win-win situation for consumers, firms and reviewers. Managerial implications for online marketing managers are also discussed.
Linking workplace bullying and EVLN outcomes
Authors: Rai Arpana , Agarwal Upasna A. 
Published: January 2019

PurposeThe purpose of this paper is to examine the relationship between workplace bullying and EVLN outcomes with psychological contract violation as a mediator and workplace friendship as a moderator.Design/methodology/approachData were collected from 835 full-time Indian managerial employees working in different Indian organizations.FindingsResults revealed that workplace bullying positively related to exit and neglect and negatively related to voice and loyalty. PCV mediated bullying–EVLN outcomes relationship and effects of workplace bullying on proposed outcomes were weaker in the presence of high workplace friendship.Research limitations/implicationsA cross-sectional design and use of self-reported questionnaire data are few limitations of this study.Originality/valueThis study adds to the limited literature examining EVLN typology in response to workplace bullying. This study is one of the rare attempts to examine bullying–outcomes relationships in the Indian context.
What strategy of human resource management to retain older workers?
Authors: Mansour Sari , Tremblay Diane-Gabrielle 
Published: January 2019

PurposeBased on the theory of conservation of resources (Hobfoll, 1989), the purpose of this paper is to propose job satisfaction as a mediator between the use of generativity and affective occupational commitment. The authors tested the mediating role of affective occupational commitment on the relationship between job satisfaction and retirement preparation.Design/methodology/approachA sequential mediation model was tested by the method of indirect effects based on a bootstrap analysis (Preacher and Hayes, 2004) based on 3,000 replications with a 95% confidence interval. The statistical treatments were carried out with the AMOS software V.22. Data were collected for a sample of 340 older workers (bridge and retirees) in Québec, Canada.FindingsResults indicate that generativity was related positively to affective occupational commitment via job satisfaction. Moreover, job satisfaction was also related positively to retirement preparation through affective occupational commitment.Practical implicationsThe results can be helpful to guide organizational efforts at retaining older workers, and also recruiting and selecting those who want to return to work after retiring. They provide an insight on the effect of one of the main human resources practices or strategies, that is, programs aiming to attract and retain older workers to stay in the workplace and to encourage retirees to return to work in the form of bridge employment for example.Originality/valueThe study adds to the existing literature by examining a sequential mediation model to understand the relationship between organizational resources, job attitudes and retirement planning. It thus answers the call for more research and a theoretical framework on these critical variables for the retirement decision-making process. The findings can also contribute to the field of knowledge retention and fulfill some gaps in the literature on this topic. Indeed, examining the use of generativity in the study can help researchers and practitioners to better understand the reasons that encourage older workers to continue working and retirees to return to work.
Corporate governance quality and premature revenue recognition: evidence from the UK
Authors: Okaily Jihad Al , Dixon Rob , Salama Aly 
Published: January 2019

Purpose
Since 2005, wide-ranging concerns have been raised about misleading revenue recognition practices, especially during and after the 2008–2009 global financial crisis. There is a lack of research into the relationship between corporate governance (CG) mechanisms and premature revenue recognition (PRR). The paper aims to discuss these issues.

Design/methodology/approach
This paper uses a generalised least squares regression analysis of a sample of 854 FTSE 350 firm–year observations. Stubben (2010) discretionary revenue (DR) model is used to measure PRR as it is considered less biased, better specified and more likely to reduce measurement error than accrual models.

Findings
The results suggest that the size of audit committees plays an effective role in constraining PRR. Moreover, PRR is more likely to be curbed in the presence of small boards comprising a higher proportion of non-executive directors. Additional tests reveal that the relationship between board size and PRR is non-linear.

Research limitations/implications
The findings address the concerns of corporate firms, capital providers, UK regulators and standard-setters regarding misleading revenue recognition practices and should be considered while setting new governance reform recommendations in response to changing economic conditions.

Originality/value
This is the first study that adopts the DR model of Stubben (2010) to capture PRR and examines its association with CG internal mechanisms. Moreover, the paper considers an important time period – from 2005 to 2013 – in which many significant developments took place.