bluuebunny/crossref_metadata_2025 huggingface dataset:
The globus pallidus pars interna in goal‐oriented and routine behaviors: Resolving a long‐standing paradox
Authors: Piron Camille , Kase Daisuke , Topalidou Meropi , Goillandeau Michel , Orignac Hugues , N'Guyen Tho‐Haï , Rougier Nicolas , Boraud Thomas
Published: February 2016

Background

There is an apparent contradiction between experimental data showing that the basal ganglia are involved in goal‐oriented and routine behaviors and clinical observations. Lesion or disruption by deep brain stimulation of the globus pallidus interna has been used for various therapeutic purposes ranging from the improvement of dystonia to the treatment of Tourette's syndrome. None of these approaches has reported any severe impairment in goal‐oriented or automatic movement.

Method

To solve this conundrum, we trained 2 monkeys to perform a variant of a 2‐armed bandit‐task (with different reward contingencies). In the latter we alternated blocks of trials with choices between familiar rewarded targets that elicit routine behavior and blocks with novel pairs of targets that require an intentional learning process.

Results

Bilateral inactivation of the globus pallidus interna, by injection of muscimol, prevents animals from learning new contingencies while performance remains intact, although slower for the familiar stimuli. We replicate in silico these data by adding lateral competition and Hebbian learning in the cortical layer of the theoretical model of the cortex–basal ganglia loop that provided the framework of our experimental approach.

Conclusion

The basal ganglia play a critical role in the deliberative process that underlies learning but are not necessary for the expression of routine movements. Our approach predicts that after pallidotomy or during stimulation, patients should have difficulty with complex decision‐making processes or learning new goal‐oriented behaviors. © 2016 Movement Disorder Society
High‐order split‐step theta methods for non‐autonomous stochastic differential equations with non‐globally Lipschitz continuous coefficients
Authors: Yue Chao
Published: February 2016

In this paper, we first propose the so‐called improved split‐step theta methods for non‐autonomous stochastic differential equations driven by non‐commutative noise. Then, we prove that the improved split‐step theta method is convergent with strong order of one for stochastic differential equations with the drift coefficient satisfying a superlinearly growing condition and a one‐sided Lipschitz continuous condition. Finally, the obtained results are verified by numerical experiments. Copyright © 2016 John Wiley & Sons, Ltd.
General stability of solutions for a viscoelastic wave equations of Kirchhoff type with acoustic boundary conditions
Authors: Kang Jum‐Ran
Published: February 2016

In this paper, we study a viscoelastic wave equations of Kirchhoff type with acoustic boundary conditions. For a viscoelastic wave equations of Kirchhoff type without strong damping, we prove an explicit and general decay rate result, using some properties of the convex functions. For a wider class of relaxation functions, we establish a more general decay result, from which the usual exponential and polynomial decay rates are only special cases. Copyright © 2016 John Wiley & Sons, Ltd.
Pullback attractors of 2D Navier–Stokes equations with weak damping, distributed delay, and continuous delay
Authors: Li Juntao , Wang Yadi , Yang Xin‐Guang
Published: February 2016

In this present paper, the existence of pullback attractors for the 2D Navier–Stokes equation with weak damping, distributed delay, and continuous delay has been considered, by virtue of classical Galerkin's method, we derived the existence and uniqueness of global weak and strong solutions. Using the Aubin–Lions lemma and some energy estimate in the Banach space with delay, we obtained the uniform bounded and existence of uniform pullback absorbing ball for the solution semi‐processes; we concluded the pullback attractors via verifying the pullback asymptotical compactness by the generalized Arzelà–Ascoli theorem. Copyright © 2016 John Wiley & Sons, Ltd.
Minimization of the ground state of the mixture of two conducting materials in a small contrast regime
Authors: Conca Carlos , Dambrine Marc , Mahadevan Rajesh , Quintero Duver
Published: February 2016

We consider the problem of distributing two conducting materials with a prescribed volume ratio in a given domain so as to minimize the first eigenvalue of an elliptic operator with Dirichlet conditions. The gap between the two conductivities is assumed to be small (low contrast regime). For any geometrical configuration of the mixture, we provide a complete asymptotic expansion of the first eigenvalue. We then consider a relaxation approach to minimize the second‐order approximation with respect to the mixture. We present numerical simulations in dimensions two and three to illustrate optimal distributions and the advantage of using a second‐order method. Copyright © 2016 John Wiley & Sons, Ltd.
On the solution of higher‐order difference equations
Authors: Akgül Ali
Published: February 2016

We introduce the reproducing kernel method to approximate solutions of difference equations. Reproducing kernel functions for difference equations are obtained. Examples that illustrate the accuracy and power of the method are given. Copyright © 2016 John Wiley & Sons, Ltd.
A scale‐free network model for HIV transmission among men who have sex with men in China
Authors: Shen Zhoufeng , Li Yabei , Yao Wei
Published: February 2016

Objective: The study aimed to analyze sexual networks and sex role preference as factors of HIV transmission among men who have sex with men (MSM) in China.

Methods: We have developed a new scale‐free network model with a sex role preference framework to study HIV transmission among MSM. We have studied the influence of different sexual networks and the effect of different proportion of sex role preference upon HIV transmission. The results are that the average ones drawn from the scenarios have been simulated for more than 30 times.

Results: Compared with the traditional mathematical model, the sexual networks provide a different prediction of the HIV transmission in the next 30 years. Without any intervention, the proportion of HIV carriers will descend after some time.

Conclusions: There is significant associations among network characteristics, sex role preference, and HIV infection. Although network‐based intervention is efficient in reducing HIV transmission among MSM, there are only few studies of the characteristics of sexual network, and such gaps deserve more attention and exploration. Copyright © 2016 John Wiley & Sons, Ltd.
Synchronous MRI of muscle motion induced by electrical stimulation
Authors: Deligianni Xeni , Pansini Michele , Garcia Meritxell , Hirschmann Anna , Schmidt‐Trucksäss Arno , Bieri Oliver , Santini Francesco
Published: February 2016

Purpose

Assessing the functionality of muscle fibers is essential to monitor both pathological and physiological processes. Here, we present a new method for accurate, quantitative measurement of muscle contraction with magnetic resonance imaging (MRI) using an electrical muscle stimulator (EMS), hence allowing the direct assessment of muscle kinematics.

Methods

A commercially available EMS device was used to induce involuntary periodic muscle contraction of the vastus lateralis muscle (VL) synchronized with high‐temporal‐resolution cine phase contrast MRI acquisition at 3T. The proposed method was evaluated in ten male volunteers at varying levels of stimulation (10–18 mA) and maximum velocity, strain, and strain rate were calculated offline.

Results

Artifact‐free velocity, strain and strain rate maps were produced and were consistent across the volunteers. Quantitatively, all parameters varied significantly at different levels of stimulation, in an approximately power‐law dependence on the stimulation current. At 18 mA maximum contraction speeds at the beginning of the contraction were 4.28 ± 2.64 cm/s; principal strain was 0.30 ± 0.12; and positive in‐plane strain rate was 0.25 ± 0.14 s−1.

Conclusion

MRI of EMS‐controlled involuntary muscle contraction is feasible and allows offline calculation of velocity, strain and strain rate maps, which appear to depend significantly on the stimulation current used. Magn Reson Med 77:664–672, 2017. © 2016 International Society for Magnetic Resonance in Medicine
On‐resonance variable delay multipulse scheme for imaging of fast‐exchanging protons and semisolid macromolecules
Authors: Xu Jiadi , Chan Kannie W.Y. , Xu Xiang , Yadav Nirbhay , Liu Guanshu , van Zijl Peter C.M.
Published: February 2016

Purpose

To develop an on‐resonance variable delay multipulse (VDMP) scheme to image magnetization transfer contrast (MTC) and the chemical exchange saturation transfer (CEST) contrast of total fast‐exchanging protons (TFP) with exchange rate above approximately 1 kHz.

Methods

A train of high power binomial pulses was applied at the water resonance. The interpulse delay, called mixing time, was varied to observe its effect on the water signal reduction, allowing separation and quantification of MTC and CEST contributions as a result of their different proton transfer rates. The fast‐exchanging protons in CEST and MTC are labeled together with the short T2 components in MTC and separated out using a variable mixing time.

Results

Phantom studies of selected metabolite solutions (glucose, glutamate, creatine, myo‐inositol), bovine serum albumin (BSA), and hair conditioner show the capability of on‐resonance VDMP to separate out exchangeable protons with exchange rates above 1 kHz. Quantitative MTC and TFP maps were acquired on healthy mouse brains using this method, showing strong gray/white matter contrast for the slowly transferring MTC protons, whereas the TFP map was more uniform across the brain but somewhat higher in gray matter.

Conclusions

The new method provides a simple way of imaging fast‐exchanging protons and MTC components with a slow transfer rate. Magn Reson Med 77:730–739, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Copper stress‐induced changes in leaf soluble proteome of Cu‐sensitive and tolerant Agrostis capillaris L. populations
Authors: Hego Elena , Vilain Sébastien , Barré Aurélien , Claverol Stéphane , Dupuy Jean‐William , Lalanne Céline , Bonneu Marc , Plomion Christophe , Mench Michel
Published: February 2016

Changes in leaf soluble proteome were explored in 3‐month‐old plants of metallicolous (M) and nonmetallicolous (NM) Agrostis capillaris L. populations exposed to increasing Cu concentrations (1–50 μM) to investigate molecular mechanisms underlying plant responses to Cu excess and tolerance of M plants. Plants were cultivated on perlite (CuSO4 spiked‐nutrient solution). Soluble proteins, extracted by the trichloroacetic acid/acetone procedure, were separated with 2‐DE (linear 4–7 pH gradient). Analysis of CCB‐stained gels (PDQuest) reproducibly detected 214 spots, and 64 proteins differentially expressed were identified using LC‐MS/MS. In both populations, Cu excess impacted both light‐dependent (OEE, cytochrome b6‐f complex, and chlorophyll a‐b binding protein), and ‐independent (RuBisCO) photosynthesis reactions, more intensively in NM leaves (ferredoxin‐NADP reductase and metalloprotease FTSH2). In both populations, upregulation of isocitrate dehydrogenase and cysteine/methionine synthases respectively suggested increased isocitrate oxidation and enhanced need for S‐containing amino‐acids, likely for chelation and detoxification. In NM leaves, an increasing need for energetic compounds was indicated by the stimulation of ATPases, glycolysis, pentose phosphate pathway, and Calvin cycle enzymes; impacts on protein metabolism and oxidative stress increase were respectively suggested by the rise of chaperones and redox enzymes. Overexpression of a HSP70 may be pivotal for M Cu tolerance by protecting protein metabolism. All MS data have been deposited in the ProteomeXchange with the dataset identifier PXD001930 (http//proteomecentral.proteomexchange.org/dataset/PXD001930).
Silicon thin film photodetectors for multi‐channel fluorescence detection in a microfluidic point‐of‐care testing device
Authors: Berner Marcel , Rothemund Ralph , Vollmer Sergej , Schubert Markus , Hilbig Urs , Gauglitz Günter
Published: February 2016

Fluorescence spectroscopy is a highly sensitive detection method widely used in analytical chemistry, bioanalytics, and medicine. The here presented amorphous silicon (a‐Si:H) based thin film photodetector arrays contribute to the miniaturization of this measurement method and thereby enable integration of a point‐of‐care testing (POCT) device. Revealed from photocurrent decay measurements, the limit of detection of the photodiodes with an active area A = 36.3 mm2 is in the 100 fA‐range. Dark current analysis at zero bias voltage yields a standard deviation σ = 4.4 fA for the thermally generated noise of the nip photodiodes. In the context of the desired application, a minimum detectable fluorescence radiation intensity Umin = 4.5 pW cm−2 with a dynamic range DNR = 78 dB is estimated. At the emission peak wavelength λem = 667 nm and with a bandwidth Δf = 0.25 Hz the photodiodes reach a noise equivalent power NEP = 54.6 fW Hz−1/2 and therewith a specific detectivity D* = 1.1 × 1013 Jones. Fluorescence measurements with the dye DY‐636 diluted in pure water with a molar concentration c = 1.31 μM demonstrate the suitability of the multi‐channel photodetectors for high‐sensitivity fluorescence spectroscopy.

Low‐signal a‐Si:H photodetector multi‐channel chips in different geometrical layouts with an active area of up to 36.3 mm2 per diode.
Efficient paillier cryptoprocessor for privacy‐preserving data mining
Authors: San Ismail , At Nuray , Yakut Ibrahim , Polat Huseyin
Published: February 2016

Paillier cryptosystem is extensively utilized as a homomorphic encryption scheme to ensure privacy requirements in many privacy‐preserving data mining schemes. However, overall performance of the applications employing Paillier cryptosystem intrinsically degrades because of modular multiplications and exponentiation operations performed by the cryptosystem. In this study, we investigate how to tackle with such performance degradation because of Paillier cryptosystem. We first exploit parallelism among the operations in the cryptosystem and interleaving among independent operations. Then, we develop hardware realization of our scheme using field‐programmable gate arrays. As a case study, we evaluate our cryptoprocessor for a well‐known privacy‐preserving set intersection protocol. We demonstrate how the proposed cryptoprocessor responds promising performance for hard real‐time privacy‐preserving data mining applications. Copyright © 2016 John Wiley & Sons, Ltd.
Organ‐on‐a‐Chip Systems: Microengineering to Biomimic Living Systems
Authors: Zheng Fuyin , Fu Fanfan , Cheng Yao , Wang Chunyan , Zhao Yuanjin , Gu Zhongze
Published: February 2016

“Organ‐on‐a‐chip” systems integrate microengineering, microfluidic technologies, and biomimetic principles to create key aspects of living organs faithfully, including critical microarchitecture, spatiotemporal cell–cell interactions, and extracellular microenvironments. This creative platform and its multiorgan integration recapitulating organ‐level structures and functions can bring unprecedented benefits to a diversity of applications, such as developing human in vitro models for healthy or diseased organs, enabling the investigation of fundamental mechanisms in disease etiology and organogenesis, benefiting drug development in toxicity screening and target discovery, and potentially serving as replacements for animal testing. Recent advances in novel designs and examples for developing organ‐on‐a‐chip platforms are reviewed. The potential for using this emerging technology in understanding human physiology including mechanical, chemical, and electrical signals with precise spatiotemporal controls are discussed. The current challenges and future directions that need to be pursued for these proof‐of‐concept studies are also be highlighted.
Resistance to ethanol sensitization is associated with a loss of synaptic plasticity in the hippocampus
Authors: Coune F. , Silvestre de Ferron B. , González‐Marín M.C. , Antol J. , Naassila M. , Pierrefiche O.
Published: February 2016

Behavioral sensitization to repeated ethanol (EtOH) exposure induces an increase in locomotor activity in mice. However, not all animals express such sensitization. Although the literature indicated that the hippocampus may play a role in EtOH sensitization, it is not known whether behavioral sensitization to EtOH is associated with preferential changes in bidirectional synaptic plasticity, i.e., LTP and LTD, two markers of learning capabilities that have also been shown to be involved in addictive behavior. In the present study, we examined whether the vulnerability to develop and express behavioral sensitization to EtOH is associated with altered bidirectional synaptic plasticity in the CA1 area of the dorsal hippocampus. For this purpose, we analyzed both LTP and LTD in resistant and sensitized mice during the expression phase, i.e., 7 days after 10 days of repeated EtOH i.p. administration. We found that resistant mice showed a lack of LTD without changes in LTP. The lack of LTD was associated with an increase in GluN2A protein level and was not due to an altered level of neuronal activity, since no difference was observed between the number of c‐FOS positive neurons in sensitized and resistant mice. Given that both types of synaptic plasticity signals may have distinct roles in specific learning and behaviors, our results suggest that resistant mice could exhibit different phenotypes in terms of learning/memory and addictive behaviors compared to sensitized ones. Synapse 71:e21899, 2017. © 2016 Wiley Periodicals, Inc.
Systematic Review of Postgraduate Surgical Education in Low‐ and Middle‐Income Countries
Authors: Rickard Jennifer
Published: February 2016

Surgical care is recognized as an important component of public health, however, many low‐ and middle‐ income countries (LMICs) are faced with a shortage of trained personnel. In response to this unmet need, many countries have developed local postgraduate training programs in surgery. This study aims to characterize general surgery postgraduate education in LMICs. PubMed, EMBASE, and Global Index Medicus databases were searched for articles related to postgraduate general surgery education in LMICs. Studies in other surgical specialties and those published prior to 1990 were excluded. Data were collected on the characteristics of postgraduate training programs. Sixty‐four articles discussed postgraduate surgical education in LMICs. Programs in 34 different countries and 6 different regions were represented. Nine countries were low‐income, 12 were low‐middle‐income, and 13 were upper‐middle‐income countries. Sixty‐four articles described aspects of the local postgraduate training program. Prior to postgraduate training, residents complete an undergraduate medical degree with 19 programs describing a pre‐training experience such as internship. Surgical curricula were broad‐based to prepare trainees to work in low‐resource settings. At the completion of postgraduate training, examination formats varied including oral, written, and clinical exams. Postgraduate general surgery programs ranged from 2.5 to 7 years. Postgraduate surgical education is one mechanism to increase surgical capacity in LMICs. Different strategies have been employed to improve surgical education in LMICs and learning from these programs can optimize surgical education across teaching sites.
Evaluating the Diagnostic Yield of Computed Tomography-Guided Aspirations in Suspected Post-operative Spine Infections
Authors: Jo Jonathan E. , Miller Andy O. , Cohn Matthew R. , Nemani Venu M. , Schneider Robert , Lebl Darren R.
Published: February 2016

Background

Early detection of surgical site infection (SSI) following spinal surgery would allow for prompt treatment and would improve overall outcome, yet early diagnosis is a challenge. Computed tomography (CT) guided aspiration of fluid collections may aid in diagnosis, as its diagnostic utility has previously been demonstrated in the setting of hip SSI, knee SSI, and spontaneous diskitis. There is no literature on its use in post-operative spinal SSIs.

Questions/Purposes

The current study aims to (1) determine the diagnostic value of CT-guided aspiration in evaluating suspected SSI; (2) identify the characteristics of the clinical presentation that are predictive of SSI; and (3) identify characteristics of the hematologic workup that are predictive of SSI.

Methods

Thirty patients who underwent CT-guided aspiration of paraspinal post-operative fluid collections and culture of aspirate fluid over the 6-year period from 2006 to 2011 were retrospectively reviewed. Aspirate fluid culture results were compared to intraoperative cultures, which were used as the “gold standard” for diagnosing SSI. The diagnostic value was evaluated by determining the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of aspirate fluid cultures. Clinical presentation, patient demographics, comorbidities, and laboratory values were reviewed for association with infection risk.

Results

Eleven of thirty patients undergoing CT-guided aspiration were subsequently confirmed to have SSI through positive cultures. Wound drainage, wound erythema, elevated ESR, and cloudiness of aspirate fluid were associated with SSI. The sensitivity and specificity of aspirate cultures were 36.4 and 89.5%, respectively, and the respective positive predictive value (PPV) and negative predictive value (NPV) were 66.7 and 70.8%.

Conclusions

Cloudy aspirate fluid was highly suggestive of infection, while wound erythema, drainage, and elevated ESR were also suggestive of SSI. CT-guided aspirations are a useful adjunct tool in evaluating for SSI but further studies are necessary before it can be considered a stand-alone diagnostic procedure.
Análisis de los factores del comportamiento organizacional en jóvenes que están iniciando su carrera laboral
Authors: Madero-Gómez Sergio M. , Olivas-Luján Miguel R.
Published: February 2016

La presente investigación cuantitativa tiene como finalidad explorar los factores del comportamiento organizacional en jóvenes que inician su carrera laboral, para lo cual se diseño un instrumento de medida con 35 ítems, con resultados válidos y confiables, aplicado a 215 estudiantes de una universidad privada del noreste de México. Como resultado se pudo observar que las variables utilizadas en el modelo de investigación mostraron el mismo comportamiento entre las personas que se encontraban en su primera experiencia laboral y las que ya habían trabajado anteriormente. Sin embargo, el esfuerzo realizado, el apoyo organizacional percibido, la intención de separación y la percepción económica presentan diferencias estadísticamente significativas utilizando otros factores de comparación.
A Bipartite Network-Based Method for Prediction of Long Non-Coding RNA–Protein Interactions
Authors: Ge Mengqu , Li Ao , Wang Minghui
Published: February 2016

As one large class of non-coding RNAs (ncRNAs), long ncRNAs (lncRNAs) have gained considerable attention in recent years. Mutations and dysfunction of lncRNAs have been implicated in human disorders. Many lncRNAs exert their effects through interactions with the corresponding RNA-binding proteins. Several computational approaches have been developed, but only few are able to perform the prediction of these interactions from a network-based point of view. Here, we introduce a computational method named lncRNA–protein bipartite network inference (LPBNI). LPBNI aims to identify potential lncRNA–interacting proteins, by making full use of the known lncRNA–protein interactions. Leave-one-out cross validation (LOOCV) test shows that LPBNI significantly outperforms other network-based methods, including random walk (RWR) and protein-based collaborative filtering (ProCF). Furthermore, a case study was performed to demonstrate the performance of LPBNI using real data in predicting potential lncRNA–interacting proteins.
Helping others or oneself: How direction of comparison affects prosocial behavior
Authors: Schlosser Ann E. , Levy Eric
Published: February 2016

Despite the frequency with which individuals compare themselves to a benchmark, little research has examined the implications of such comparisons on willingness to help others. Such comparisons can vary in direction by suggesting that one is doing better than a benchmark (a downward comparison) or worse than a benchmark (an upward comparison). We argue and find that by being relatively better off, people making downward comparisons are more likely to view giving as a means of expressing altruistic values (e.g., to give back and be a better person) compared to those making upward comparisons. Consequently, when the context highlights the instrumentality of giving for more altruistic reasons (to benefit others), they are more willing to give than are those making upward comparisons. Furthermore, this difference is mitigated when the context highlights the instrumentality of giving to benefit the self, and is reversed when the instrumentality of giving for benefitting others is challenged. We obtain support for this account across four studies, through both moderation and mediation, and across both monetary and nonmonetary comparison domains.
Victim Participation in Japan: When Therapeutic Jurisprudence Meets Prosecutor Justice
Authors: HERBER Erik
Published: February 2016

This article examines how a therapeutic perspective on victim participation has been conceptualized and implemented in criminal trials in Japan after procedural reforms in 2000 and 2008. Findings are discussed with reference to therapeutic jurisprudence studies on victim participation and relevant literature on Japanese criminal justice. Analysis of policy documents, survey data, interviews, and minutes of Ministry of Justice “expert meetings” reveals how the therapeutic needs of victims and the therapeutic effects of victim participation in court proceedings have been understood and conceptualized based on generalized common-sense assumptions of legal practitioners. In court, participants’ reference to victims’ wellbeing and recovery puts pressure on judges to impose harsher punishment than usual, while reinforcing the position of prosecutors. The adopted therapeutic perspective, combined with traditionally expected displays of remorse, furthermore has the effect of limiting the defence’s ability to argue facts and circumstances favourable to the defendant.
Offering support to the general public by building CBT-based life skills: lessons learnt from an initial evaluation
Authors: Lyons D. , Collins K. , Hayes C.
Published: February 2016

Aims

Cognitive behavioural therapy (CBT) is effective for symptoms of mild to moderate depression yet access to such therapy is frequently limited. An alternative to traditional ways of delivering CBT is lower intensity methods based on self-help principles, using written CBT resources, in a group or class setting. Aware, the Irish National charity providing support to people experiencing depression, has implemented a 6-week CBT-based group programme which has been independently evaluated to demonstrate its effectiveness using quantitative and qualitative measures.

Method

Two outcome measures (the Patient Health Questionnaire – PHQ-9, and Generalised Anxiety Disorder – GAD-7) were completed and analysed using a matched pairst-test in respect of all participants at three intervals across the programme. Qualitative feedback was also sought upon completion of the course and offered insight into significant change and individual impact of the programme.

Results

A total of 2289 individuals nationwide registered for the programme through the Aware website with 1885 completing the 6 weeks. There was an average attendance of 67% for the 6-week programme. Statistically significant reductions in terms of scores of depression and anxiety were seen upon completion but earlier trends towards improvement were noted.

Conclusion

Completion of a 6-week Life Skills Programme has been associated with a reduction from moderately severe to mild scores in relation to both depressive and anxiety symptoms. Longitudinal follow-up will be required to determine if the effectiveness of the intervention is maintained but CBT-based group programmes may represent a useful alternative to traditional services to treat clinically significant depression.
Stratified gravity currents in porous media
Authors: Pegler Samuel S. , Huppert Herbert E. , Neufeld Jerome A.
Published: February 2016

We consider theoretically and experimentally the propagation in porous media of variable-density gravity currents containing a stably stratified density field, with most previous studies of gravity currents having focused on cases of uniform density. New thin-layer equations are developed to describe stably stratified fluid flows in which the density field is materially advected with the flow. Similarity solutions describing both the fixed-volume release of a distributed density stratification and the continuous input of fluid containing a distribution of densities are obtained. The results indicate that the density distribution of the stratification significantly influences the vertical structure of the gravity current. When more mass is distributed into lighter densities, it is found that the shape of the current changes from the convex shape familiar from studies of the uniform-density case to a concave shape in which lighter fluid accumulates primarily vertically above the origin of the current. For a constant-volume release, the density contours stratify horizontally, a simplification which is used to develop analytical solutions. For currents introduced continuously, the horizontal velocity varies with vertical position, a feature which does not apply to uniform-density gravity currents in porous media. Despite significant effects on vertical structure, the density distribution has almost no effect on overall horizontal propagation, for a given total mass. Good agreement with data from a laboratory study confirms the predictions of the model.
Travelling wave states in pipe flow
Authors: Ozcakir Ozge , Tanveer Saleh , Hall Philip , Overman Edward A.
Published: February 2016

In this paper, we have found two new nonlinear travelling wave solutions in pipe flows. We investigate possible asymptotic structures at large Reynolds number $R$ when wavenumber is independent of $R$ and identify numerically calculated solutions as finite $R$ realizations of a nonlinear viscous core (NVC) state that collapses towards the pipe centre with increasing $R$ at a rate $R^{-1/4}$. We also identify previous numerically calculated states as finite $R$ realizations of a vortex wave interacting (VWI) state with an asymptotic structure similar to the ones in channel flows studied earlier by Hall & Sherwin (J. Fluid Mech., vol. 661, 2010, pp. 178–205). In addition, asymptotics suggests the possibility of a VWI state that collapses towards the pipe centre like $R^{-1/6}$, though this remains to be confirmed numerically.
Influence of surface viscosity on droplets in shear flow
Authors: Gounley J. , Boedec G. , Jaeger M. , Leonetti M.
Published: February 2016

The behaviour of a single droplet in an immiscible external fluid, submitted to shear flow is investigated using numerical simulations. The surface of the droplet is modelled by a Boussinesq–Scriven constitutive law involving the interfacial viscosities and a constant surface tension. A numerical method using Loop subdivision surfaces to represent droplet interface is introduced. This method couples boundary element method for fluid flows and finite element method to take into account the stresses due to the surface dilational and shear viscosities and surface tension. Validation of the numerical scheme with respect to previous analytic and computational work is provided, with particular attention to the viscosity contrast and the shear and dilational viscosities characterized both by a Boussinesq number$B_{q}$. Then, influence of equal surface viscosities on steady-state characteristics of a droplet in shear flow are studied, considering both small and large deformations and for a large range of bulk viscosity contrast. We find that small deformation analysis is surprisingly predictive at moderate and high surface viscosities. Equal surface viscosities decrease the Taylor deformation parameter and tank-treading angle and also strongly modify the dynamics of the droplet: when the Boussinesq number (surface viscosity) is large relative to the capillary number (surface tension), the droplet displays damped oscillations prior to steady-state tank-treading, reminiscent from the behaviour at large viscosity contrast. In the limit of infinite capillary number$Ca$, such oscillations are permanent. The influence of surface viscosities on breakup is also investigated, and results show that the critical capillary number is increased. A diagram$(B_{q};Ca)$of breakup is established with the same inner and outer bulk viscosities. Additionally, the separate roles of shear and dilational surface viscosity are also elucidated, extending results from small deformation analysis. Indeed, shear (dilational) surface viscosity increases (decreases) the stability of drops to breakup under shear flow. The steady-state deformation (Taylor parameter) varies nonlinearly with each Boussinesq number or a linear combination of both Boussinesq numbers. Finally, the study shows that for certain combinations of shear and dilational viscosities, drop deformation for a given capillary number is the same as in the case of a clean surface while the inclination angle varies.
On a suspension of nearly spherical colloidal particles under large-amplitude oscillatory shear flow
Authors: Khair Aditya S.
Published: February 2016

The dynamics of a dilute, monodisperse suspension of nearly spherical particles that undergo Brownian rotations in an oscillatory simple shear flow is quantified, as a paradigm for large-amplitude oscillatory shear (LAOS) rheology of complex fluids. We focus on the ‘strongly nonlinear’ regime of LAOS, defined by ${\it\beta}\gg 1$ and ${\it\beta}/{\it\alpha}\gg 1$, where ${\it\beta}$ is a dimensionless shear rate (or Weissenberg number) and ${\it\alpha}$ is a dimensionless oscillation frequency (or Deborah number). We derive an asymptotic solution for the long-time periodic orientation probability density function of the particles. Our analysis reveals that the orientation dynamics consists of ‘core’ regions of rapid oscillation (on the time scale of the inverse of the shear-rate amplitude), separated by comparatively short ‘turning’ regions of slow evolution when the imposed flow vanishes. Uniformly valid approximations to the shear stress and normal stress differences (NSDs) of the suspension are then constructed: the non-Newtonian contribution to the shear stress, first NSD and second NSD, decays as ${\it\beta}^{-3/2}$, ${\it\beta}^{-1}$ and ${\it\beta}^{-1/2}$, respectively, at large ${\it\beta}$. These stress scalings originate from the orientation dynamics at the turning regions. Therefore, it is the occasions when the flow vanishes that dominate the rheology of this paradigmatic complex fluid under LAOS.
Differences in prescribing psychotropic drugs for elderly with depression
Authors: Huang Yu-Chi , Wang Liang-Jen , Chong Mian-Yoon
Published: February 2016

Objective

The escalating tendency of elderly population aged 65 and over, which grown up to 9% since 2001 in Taiwan, remarks the important issue of mental health among ageing population. Depression in the elderly is frequently undetected or inadequately treated. This study aimed to investigate the pharmacotherapy of elderly patients with depression by comparing the patterns of prescribing psychotropic drugs (psychotropics) of psychiatrists and non-psychiatrists.

Methods

A random sampling of 5% of inpatients from the National Health Insurance (NHI) database in Taiwan from 2001 to 2003 was selected. In all, 1058 (0.9%) inpatients aged 65 and older with a diagnosis of any depressive disorder were included. The psychotropic prescribing pattern and the dosages used were analysed and compared. Physician specialties were based on the record of NHI database. Non-psychiatrists were defined by physicians other than psychiatry.

Results

A total of 88% of elderly depressed inpatients had two or more comorbid physical illnesses. The most commonly prescribed psychotropics were: antidepressants (71.4%), anxiolytics (62.6%) and hypnotics (51.4%). Psychiatrists had a higher rate of prescribing psychotropics, except anxiolytics, than non-psychiatrists. Although selective serotonin reuptake inhibitors were commonly prescribed, non-psychiatrists preferred the use of tricyclic antidepressants and moclobemide. Trazodone was the most preferred antidepressant, but was generally used in low dosages.

Conclusion

Psychiatrists generally utilised higher dosages of newer antidepressants than non-psychiatrists. Differences in the prescribing pattern of psychotropics existed between physician specialties. Further investigations are warranted to determine how the selection and dosing of drugs influence the outcome of depression on the elderly.
Dictyophara europaea(Hemiptera: Fulgoromorpha: Dictyopharidae): description of immatures, biology and host plant associations
Authors: Krstić O. , Cvrković T. , Mitrović M. , Toševski I. , Jović J.
Published: February 2016

The European lantern flyDictyophara europaea(Linnaeus, 1767), is a polyphagous dictyopharid planthopper of Auchenorrhyncha commonly found throughout the Palaearctic. Despite abundant data on its distribution range and reports on its role in the epidemiology of plant-pathogenic phytoplasmas (Flavescence dorée, FD-C), literature regarding the biology and host plants of this species is scarce. Therefore, the aims of our study were to investigate the seasonal occurrence, host plant associations, oviposition behaviour and immature stages of this widespread planthopper of economic importance. We performed a 3-year field study to observe the spatio-temporal distribution and feeding sources ofD. europaea. The insects's reproductive strategy, nymphal molting and behaviour were observed under semi-field cage conditions. Measurement of the nymphal vertex length was used to determine the number of instars, and the combination of these data with body length, number of pronotal rows of sensory pits and body colour pattern enabled the discrimination of each instar. We provide data showing thatD. europaeahas five instars with one generation per year and that it overwinters in the egg stage. Furthermore, our study confirmed highly polyphagous feeding nature ofD. europaea, for all instars and adults, as well as adult horizontal movement during the vegetation growing season to the temporarily preferred feeding plants where they aggregate during dry season. We foundD. europaeaadult aggregation in late summer onClematis vitalbaL. (Ranunculaceae), a reservoir plant of FD-C phytoplasma strain; however, this appears to be a consequence of forced migration due to drying of herbaceous vegetation rather than to a high preference ofC. vitalbaas a feeding plant. Detailed oviposition behaviour and a summary of the key discriminatory characteristics of the five instars are provided. Emphasis is placed on the economic importance ofD. europaeabecause of its involvement in epidemiological cycles of phytoplasma-induced plant diseases.
Slow and fast development in two aphidophagous ladybirds on scarce and abundant prey supply
Authors: Singh N. , Mishra G. , Omkar
Published: February 2016

Developmental rates are highly variable, both within and between genotypes and populations. But the rationale for two differential (slow and fast) developmental rates within same cohort under varying prey supply has yet not been explored. For this purpose, we investigated the effect of scarce and abundant prey supply on slow and fast development at 27°C in two aphidophagous ladybirds,Menochilus sexmaculatus(Fabricius) andPropylea dissecta(Mulsant) and its effect on their body mass and reproductive attributes. The ladybirds were provided with scarce and abundant supply ofAphis craccivoraKoch under standardized abiotic conditions in the laboratory. A clear bimodal (two peaks, where the first peak represented the fast developing individuals and the second peak slow developing individuals) pattern of distribution for both prey supplies was obtained, which got skewed with change in prey supply. On abundant prey supply, more fast developing individuals (139M. sexmaculatusand 123P. dissecta) were found and less (46M. sexmaculatusand 36P. dissecta) on scarce prey supply. Slow developing individuals had female biased sex ratio, higher longevity and lower body mass. Fast developing females laid higher number of eggs with higher egg viability. Results of the study are indicative of occurrence and constancy of the slow and fast developing individuals in the egg batch.
Assessing the Impact of Political Scandals on Attitudes toward Democracy: Evidence from Canada's Sponsorship Scandal
Authors: Ruderman Nick , Nevitte Neil
Published: February 2016

Satisfaction with the workings of democracy seems to have declined in Canada, as it has in other established democracies. Political scandals are one frequently invoked explanation for that shift. But there is substantial scholarly disagreement about whether political scandals undermine democratic satisfaction. This paper uses evidence from a conveniently timed round of the CES (Canadian Election Study) from 2004, as well as the CES panel from 2004 and 2006, to explore this relationship more definitively than is usually possible. The results indicate that the scandal eroded satisfaction with the way democracy works but did not undermine support for democracy more generally.
Learning to trust: trust and attachment in early psychosis
Authors: Fett A.-K. J. , Shergill S. S. , Korver-Nieberg N. , Yakub F. , Gromann P. M. , Krabbendam L.
Published: February 2016

Background

Distrust and social dysfunction are characteristic in psychosis and may arise from attachment insecurity, which is elevated in the disorder. The relationship between trust and attachment in the early stages of psychosis is unknown, yet could help to understand interpersonal difficulties and disease progression. This study aimed to investigate whether trust is reduced in patients with early psychosis and whether this is accounted for by attachment avoidance and attachment anxiety.

Method

We used two trust games with a cooperative and unfair partner in a sample of 39 adolescents with early psychosis and 100 healthy controls.

Results

Patients had higher levels of attachment anxiety, but the groups did not differ in attachment avoidance. Basic trust was lower in patients than controls, as indicated by lower initial investments. During cooperation patients increased their trust towards levels of controls, i.e. they were able to learn and to override initial suspiciousness. Patients decreased their trust less than controls during unfair interactions. Anxious attachment was associated with higher basic trust and higher trust during unfair interactions and predicted trust independent of group status.

Discussion

Patients showed decreased basic trust but were able to learn from the trustworthy behaviour of their counterpart. Worries about the acceptance by others and low self-esteem are associated with psychosis and attachment anxiety and may explain behaviour that is focused on conciliation, rather than self-protection.
Multidimensional assessment of impulsivity in schizophrenia, bipolar disorder, and major depressive disorder: testing for shared endophenotypes
Authors: Fortgang R. G. , Hultman C. M. , van Erp T. G. M. , Cannon T. D.
Published: February 2016

Background

Impulsivity is associated with bipolar disorder as a clinical feature during and between manic episodes and is considered a potential endophenotype for the disorder. Schizophrenia and major depressive disorder share substantial genetic overlap with bipolar disorder, and these two disorders have also been associated with elevations in impulsivity. However, little is known about the degree of overlap among these disorders in discrete subfacets of impulsivity and whether any overlap is purely phenotypic or due to shared genetic diathesis.

Method

We focused on five subfacets of impulsivity: self-reported attentional, motor, and non-planning impulsivity, self-reported sensation seeking, and a behavioral measure of motor inhibition (stop signal reaction time; SSRT). We examined these facets within and across disorder proband and co-twin groups, modeled heritability, and tested for endophenotypic patterning in a sample of twin pairs recruited from the Swedish Twin Registry (N= 420).

Results

We found evidence of moderate to high levels of heritability for all five subfacets. All three proband groups and their unaffected co-twins showed elevations on attentional, motor, and non-planning impulsivity. Schizophrenia probands (but not their co-twins) showed significantly lower sensation seeking, and schizophrenia and bipolar disorder probands (but not in their co-twins) had significantly longer SSRTs, compared with healthy controls and the other groups.

Conclusions

Attentional, motor, and non-planning impulsivity emerged as potential shared endophenotypes for the three disorders, whereas sensation seeking and SSRT were associated with phenotypic affection but not genetic loading for these disorders.
Developing the assistive technology consumer market for people aged 50–70
Authors: WARD GILLIAN , FIELDEN SIMON , MUIR HELEN , HOLLIDAY NIKKI , URWIN GERRY
Published: February 2016

Within the United Kingdom (UK), assisted living technologies are mostly provided through statutory health and social care services following assessment of individual need and application of eligibility criteria. This paper describes the first UK study to explore and develop business approaches and innovations required to make electronic assisted living technologies more accessible to consumers in their fifties and sixties. A robust mixed-method approach was used including a large sample size for a consumer survey, triangulation of methods and confirmation of research findings through validation workshops. This three-year study makes significant and original contributions to understanding consumer needs in this rapidly changing market and offers unique insights into the needs and wants of people aged 50–70. Analysis shows significant differences between consumer and business perceptions, indicating that marketing is not closely aligned to consumers' needs and is affecting the development of the market. New approaches to consumer-led business models are presented to improve information and marketing aimed at 50–70-year-old consumers. A ‘Broker/Independent Advisor’ business model showed most potential for meeting the needs of both consumer and business stakeholders. Findings support future development of an assisted living consumer market to meet growing levels of need and demand, and to offer greater consumer choice of mainstream technologies to enable people to age in place.