bluuebunny/crossref_metadata_2025 huggingface dataset:
A qualitative review of sports concussion education: prime time for evidence-based knowledge translation
Authors: Mrazik Martin , Dennison Christopher R , Brooks Brian L , Yeates Keith Owen , Babul Shelina , Naidu Dhiren
Published: August 2015

Background

Educating athletes, coaches, parents and healthcare providers about concussion management is a public health priority. There is an abundance of information on sports concussions supported by position statements from governing sport and medical organisations. Yet surveys of athletes, parents, coaches and healthcare providers continue to identify multiple barriers to the successful management of sports concussion. To date, efforts to provide education using empirically sound methodologies are lacking.

Purpose

To provide a comprehensive review of scientific research on concussion education efforts and make recommendations for enhancing these efforts.

Study design

Qualitative literature review of sports concussion education.

Methods

Databases including PubMed, Sport Discus and MEDLINE were searched using standardised terms, alone and in combination, including ‘concussion’, ‘sport’, ‘knowledge’, ‘education’ and ‘outcome’.

Results

Studies measuring the success of education interventions suggest that simply presenting available information may help to increase knowledge about concussions, but it does not produce long-term changes in behaviour among athletes. Currently, no empirical reviews have evaluated the success of commercially available sports concussion applications. The most successful education efforts have taken steps to ensure materials are user-friendly, interactive, utilise more than one modality to present information and are embedded in mandated training programmes or support legislation. Psychosocial theory-driven methods used to understand and improve ‘buy in’ from intended audiences have shown promise in changing behaviour.

Conclusions

More deliberate and methodologically sound steps must be taken to optimise education and knowledge translation efforts in sports concussion.
Why do patients with stroke not receive the recommended amount of active therapy (ReAcT)? Study protocol for a multisite case study investigation
Authors: Clarke David J , Tyson Sarah , Rodgers Helen , Drummond Avril , Palmer Rebecca , Prescott Matthew , Tyrrell Pippa , Burton Louisa , Grenfell Katie , Brkic Lianne , Forster Anne
Published: August 2015

Introduction

Increased frequency and intensity of inpatient therapy contributes to improved outcomes for stroke survivors. Differences exist in the amount of therapy provided internationally. In England, Wales and Northern Ireland it is recommended that a minimum of 45 min of each active therapy should be provided at least 5 days a week provided the therapy is appropriate and that the patient can tolerate this. Sentinel Stroke National Audit Programme (2014) data demonstrate this standard is not being achieved for most patients. No research been undertaken to explore how therapists in England manage their practice to meet time-specific therapy recommendations. The ReAcT study aims to develop an in-depth understanding of stroke therapy provision, including how the guideline of 45 min a day of each relevant therapy, is interpreted and implemented by therapists, and how it is experienced by stroke-survivors and their families.

Methods and analysis

A multisite ethnographic case study design in a minimum of six stroke units will include modified process mapping, observations of service organisation, therapy delivery and documentary analysis. Semistructured interviews with therapists and service managers (n=90), and with patients and informal carers (n=60 pairs) will be conducted. Data will be analysed using the Framework approach.

Ethics and dissemination

The study received a favourable ethical opinion via the National Research Ethics Service (reference number: 14/NW/0266). Participants will provide written informed consent or, where stroke-survivors lack capacity, a consultee declaration will be sought. ReAcT is designed to generate insights into the organisational, professional, social, practical and patient-related factors acting as facilitators or barriers to providing the recommended amount of therapy. Provisional recommendations will be debated in consensus meetings with stakeholders who have not participated in ReAcT case studies or interviews. Final recommendations will be disseminated to therapists, service managers, clinical guideline developers and policymakers and stroke-survivors and informal carers.
Pre-exposure and postexposure prophylaxes and the combination HIV prevention methods (The Combine! Study): protocol for a pragmatic clinical trial at public healthcare clinics in Brazil
Authors: Grangeiro Alexandre , Couto Márcia Thereza , Peres Maria Fernanda , Luiz Olinda , Zucchi Eliana Miura , Castilho Euclides Ayres de , Estevam Denize Lotufo , Alencar Rosa , Wolffenbüttel Karina , Escuder Maria Mercedes , Calazans Gabriela , Ferraz Dulce , Arruda Érico , Corrêa Maria da Gloria , Amaral Fabiana Rezende , Santos Juliane Cardoso Villela , Alvarez Vivian Salles , Kietzmann Tiago
Published: August 2015

Introduction

Few results from programmes based on combination prevention methods are available. We propose to analyse the degree of protection provided by postexposure prophylaxis (PEP) for consensual sexual activity at healthcare clinics, its compensatory effects on sexual behaviour; and the effectiveness of combination prevention methods and pre-exposure prophylaxis (PrEP), compared with exclusively using traditional methods.

Methods and analysis

A total of 3200 individuals aged 16 years or older presenting for PEP at 5 sexually transmitted disease (STD)/HIV clinics in 3 regions of Brazil will be allocated to one of two groups: the PEP group—individuals who come to the clinic within 72 h after a sexual exposure and start PEP; and the non-PEP group—individuals who come after 72 h but within 30 days of exposure and do not start PEP. Clinical follow-up will be conducted initially for 6 months and comprise educational interventions based on information and counselling for using prevention methods, including PrEP. In the second study phase, individuals who remain HIV negative will be regrouped according to the reported use of prevention methods and observed for 18 months: only traditional methods; combined methods; and PrEP. Effectiveness will be analysed according to the incidence of HIV, syphilis and hepatitis B and C and protected sexual behaviour. A structured questionnaire will be administered to participants at baseline and every 6 months thereafter. Qualitative methods will be employed to provide a comprehensive understanding of PEP-seeking behaviour, preventive choices and exposure to HIV.

Ethics and dissemination

This study will be conducted in accordance with the resolution of the School of Medicine Research Ethics Commission of Universidade de São Paulo (protocol no. 251/14). The databases will be available for specific studies, after management committee approval. Findings will be presented to researchers, health managers and civil society members by means of newspapers, electronic media and scientific journals and meetings.
How to build up the actionable knowledge base: the role of ‘best fit’ framework synthesis for studies of improvement in healthcare
Authors: Booth Andrew , Carroll Christopher
Published: August 2015

Increasing recognition of the role and value of theory in improvement work in healthcare offers the prospect of capitalising upon, and consolidating, actionable lessons from synthesis of improvement projects and initiatives. We propose that informed use of theory can (i) provide a mechanism by which to collect and organise data from a body of improvement work, (ii) offer a framework for analysis and identification of lessons learnt and (iii) facilitate an evaluation of the feasibility, effectiveness and acceptability of improvement programmes. Improvement practitioners can benefit from using an underpinning external structure as a lens by which to examine the specific achievements of their own projects alongside comparable initiatives led by others. We demonstrate the utility of a method known as ‘best fit framework synthesis’ (BFFS) in offering a ubiquitous and versatile means by which to collect, analyse and evaluate improvement work in healthcare. First reported in 2011, BFFS represents a pragmatic, flexible approach to integrating theory with findings from practice. A deductive phase, where a review team seeks to accommodate a substantial part of the data, is followed by an inductive phase, in which the team explores data not accommodated by the framework. We explore the potential for BFFS within improvement work by drawing upon the evidence synthesis methodology literature and practical examples of improvement work reported inBMJ Quality and Safety(2011–2015). We suggest four variants of BFFS that may have particular value in synthesising a body of improvement work. We conclude that BFFS, alongside other approaches that seek to optimise the contribution of theory to improvement work, represents one important enabling mechanism by which to establish the rigour and scientific credentials of the emerging discipline of ‘improvement science’.
From many deaths to some few cases of drug-resistant tuberculosis: travelling with the systems quality improvement model in Lacs Health District, Togo
Authors: Afanvi Kossivi Agbelenko
Published: August 2015

The ultimate goal of every tuberculosis (TB) treatment program is a high treatment success rate. Treatment success is extremely important because, when the rate is high, it significantly contributes to declining numbers of new cases by reducing the number and period of infectious cases, TB morbidity and mortality, and prevents the emergence of resistant strains. Our aim was to decrease TB mortality by increasing pulmonary TB patients’ treatment success rate to at least 85 % in Lacs Health District by end of July 2014.

A systems and dialogic analysis of the public health system related to TB patients’ treatment revealed that it was not performing well; we found weak coverage and quality of TB services, a poorly-functioning TB health information system, poor-performing health workforce, poor availability of HIV tests and antiretroviral for TB patients, and low degree of patients’ participation in their care. We redesigned the system to correct those weaknesses. The effectiveness of these changes was monitored using plan, do, study, act (PDSA) cycles. We increased TB patient success rate from 80% to 95% between February 2012 and July 2014.The mortality rate dropped from 13% to 3% and the failure to follow-up rate dropped from 3% to 2%.

In conclusion, district health systems performance depends on factors such as the closeness of services to population; skilled workforce; the ability to collect and analyze data and use information for action; population empowerment, and good management and improvement capabilities of management team especially the public health director. High TB patients’ success rate depends also on the availability of antiretroviral drugs. It is highly important that every district health management team member develops improvement capabilities.
Helmets for Kids: evaluation of a school-based helmet intervention in Cambodia
Authors: Ederer David J , Bui Truong Van , Parker Erin M , Roehler Douglas R , Sidik Mirjam , Florian Michael J , Kim Pagna , Sim Sophal , Ballesteros Michael F
Published: August 2015

Objective

This paper analyses helmet use before and after implementing Helmets for Kids, a school-based helmet distribution and road safety programme in Cambodia.

Methods

Nine intervention schools (with a total of 6721 students) and four control schools (with a total of 3031 students) were selected using purposive sampling to target schools where students were at high risk of road traffic injury. Eligible schools included those where at least 50% of students commute to school on bicycles or motorcycles, were located on a national road (high traffic density), had few or no street signs nearby, were located in an area with a history of crash injuries and were in a province where other Cambodia Helmet Vaccine Initiative activities occur. Programme's effectiveness at each school was measured through preintervention and postintervention roadside helmet observations of students as they arrived or left school. Research assistants conducted observations 1–2 weeks preintervention, 1–2 weeks postintervention, 10–12 weeks postintervention and at the end of the school year (3–4 months postintervention).

Results

In intervention schools, observed student helmet use increased from an average of 0.46% at 1–2 weeks preintervention to an average of 87.9% at 1–2 weeks postintervention, 83.5% at 10–12 weeks postintervention and 86.5% at 3–4 months postintervention, coinciding with the end of the school year. Increased helmet use was observed in children commuting on bicycle or motorcycle, which showed similar patterns of helmet use. Helmet use remained between 0.35% and 0.70% in control schools throughout the study period.

Conclusions

School-based helmet use programmes that combine helmet provision and road safety education might increase helmet use among children.
Calibrated integrated backscatter and myocardial fibrosis in patients undergoing cardiac surgery
Authors: Prior David L , Somaratne Jithendra B , Jenkins Alicia J , Yii Michael , Newcomb Andrew E , Schalkwijk Casper G , Black Mary J , Kelly Darren J , Campbell Duncan J
Published: August 2015

Objective

The reported association between calibrated integrated backscatter (cIB) and myocardial fibrosis is based on study of patients with dilated or hypertrophic cardiomyopathy and extensive (mean 15–34%) fibrosis. Its association with lesser degrees of fibrosis is unknown. We examined the relationship between cIB and myocardial fibrosis in patients with coronary artery disease.

Methods

Myocardial histology was examined in left ventricular epicardial biopsies from 40 patients (29 men and 11 women) undergoing coronary artery bypass graft surgery, who had preoperative echocardiography with cIB measurement.

Results

Total fibrosis (picrosirius red staining) varied from 0.7% to 4%, and in contrast to previous reports, cIB showed weak inverse associations with total fibrosis (r=−0.32, p=0.047) and interstitial fibrosis (r=−0.34, p=0.03). However, cIB was not significantly associated with other histological parameters, including immunostaining for collagens I and III, the advanced glycation end product (AGE) Nε-(carboxymethyl)lysine (CML) and the receptor for AGEs (RAGE). When biomarkers were examined, cIB was weakly associated with log plasma levels of amino-terminal pro-B-type natriuretic peptide (r=0.34, p=0.03), creatinine (r=0.33, p=0.04) and glomerular filtration rate (r=−0.33, p=0.04), and was more strongly associated with log plasma levels of soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) (r=0.44, p=0.01) and soluble RAGE (r=0.53, p=0.002).

Conclusions

Higher cIB was not a marker of increased myocardial fibrosis in patients with coronary artery disease, but was associated with higher plasma levels of sVEGFR-1 and soluble RAGE. The role of cIB as a non-invasive index of fibrosis in clinical studies of patients without extensive fibrosis is, therefore, questionable.
Ischaemia change with revascularisation versus medical therapy in reduced ejection fraction
Authors: Mentz Robert J , Fiuzat Mona , Shaw Linda K , Farzaneh-Far Afshin , M O'Connor Christopher , Borges-Neto Salvador
Published: August 2015

Objective

Nuclear imaging data demonstrate that revascularisation leads to favourable effects on ischaemia burden and improved outcomes compared with medical therapy (MT). In patients with heart failure (HF), the effects of MT versus revascularisation on ischaemia change and its independent prognostic significance requires investigation.

Methods

From the Duke Databank, we performed a retrospective analysis of 278 consecutive patients with coronary artery disease (CAD) and ejection fraction (EF) ≤40%, who underwent 2 serial myocardial perfusion scans between 1993 and 2009. Ischaemia change was calculated for patients undergoing MT alone, or revascularisation. Cox proportional hazards regression modelling was used to identify factors associated with death/myocardial infarction (MI).

Results

The magnitude of ischeamia reduction was greater with revascularisation than with MT alone (median change of −6% vs 0%, p<0.001). With revascularisation, more patients experienced ≥5% ischaemia reduction compared with MT (52% vs 25%, p<0.01) and a similar percentage experienced ≥5% ischaemia worsening (13% vs 18%, p=0.37). After risk adjustment, ≥5% ischaemia worsening was associated withdecreaseddeath/MI (HR=0.58; 95% CI 0.36 to 0.96).

Conclusions

In patients with HF with CAD, revascularisation improves long-term ischaemia burden compared with MT. Ischaemia worsening on nuclear imaging was associated with reduced risk of death/MI, potentially related to development of ischaemic viable myocardium as opposed to scar tissue.
A New Time-Mode On-Chip Oscillator-Based High Linearity and Low Power Temperature Sensor
Authors: Zhu Di , Siek Liter
Published: August 2015

This paper presents an energy-efficient and high linearity temperature sensor based on the architecture of a simple on-chip oscillator. A self-calibrated block is proposed to compensate the non-linearities of the on-chip oscillator due to PVT variations. In this manner, this on-chip oscillator-based temperature sensor has superior performance over the conventional inverter-chain-based types. In order to generalize the application, no highly linear temperature coefficient resistors are being utilized. The entire circuit is simple and easy to be scaled down. According to the verifications in 65 nm CMOS process, with one-point calibration, this temperature sensor can achieve an inaccuracy within ±1°C in the temperature range from -55°C to 125°C, with a power consumption of only 0.6 μA under 1.2 V supply voltages.
A 4-string tangle analysis of DNA-protein complexes based on difference topology
Authors: Kim Soojeong , Darcy Isabel K.
Published: August 2015

An n-string tangle is a three-dimensional ball with n-strings properly embedded in it. In the late 1980s, Ernst and Sumners introduced a tangle model for protein-DNA complexes. The protein is modeled by a three-dimensional ball and the protein-bound DNA is modeled by strings embedded inside the ball. Originally the tangle model was applied to proteins such as Tn3 resolvase which binds two DNA segments. This protein breaks and rejoins two DNA segments and can create knotted DNA. A 2-string tangle model can be used for this complex. More recently, Pathania, Jayaram and Harshey determined that the topological structure of DNA within a Mu protein complex consists of three DNA segments containing five crossings. Since Mu binds DNA sequences at three sites, this Mu protein-DNA complex can be modeled by a 3-string tangle. Darcy, Leucke and Vazquez analyzed Pathania et al.'s experimental results by using 3-string tangle analysis. There are protein-DNA complexes that involve four or more DNA sites. When a protein binds circular DNA at four sites, a protein-DNA complex can be modeled by a 4-string tangle with four loops outside of the tangle. We determine a biologically relevant 4-string tangle model. We also develop mathematics for solving 4-string tangle equations to determine the topology of DNA within a protein complex.
Thermodynamics of universe with a varying dark energy component
Authors: Ebadi H. , Moradpour H.
Published: August 2015

We consider a Friedmann–Robertson–Walker (FRW) universe filled by a dark energy (DE) candidate together with other possible sources which may include the baryonic and nonbaryonic matters. Thereinafter, we consider a situation in which the cosmos sectors do not interact with each other. By applying the unified first law of thermodynamics on the apparent horizon of the FRW universe, we show that the DE candidate may modify the apparent horizon entropy and thus the Bekenstein limit. Moreover, we generalize our study to the models in which the cosmos sectors have a mutual interaction. Our final result indicates that the mutual interaction between the cosmos sectors may add an additional term to the apparent horizon entropy leading to modify the Bekenstein limit. Relationships with previous works have been addressed throughout the paper. Finally, we investigate the validity of the second law of thermodynamics and its generalized form in the interacting and noninteracting cosmoses.
On the fundamental groups of normal varieties
Authors: Arapura Donu , Dimca Alexandru , Hain Richard
Published: August 2015

We show that the fundamental groups of normal complex algebraic varieties share many properties of the fundamental groups of smooth varieties. The jump loci of rank one local systems on a normal variety are related to the jump loci of a resolution and of a smoothing of this variety.
A note on a three-dimensional sphere theorem with integral curvature condition
Authors: Lai Mijia
Published: August 2015

In this paper, we obtain a three-dimensional sphere theorem with integral curvature condition. On a closed three manifold [Formula: see text] with constant positive scalar curvature, if a certain combination of [Formula: see text] norm of the Ricci curvature and [Formula: see text] norm of the scalar curvature is positive, then [Formula: see text] is diffeomorphic to a spherical space form.
Standing waves for a gauged nonlinear Schrödinger equation with a vortex point
Authors: Jiang Yongsheng , Pomponio Alessio , Ruiz David
Published: August 2015

This paper is motivated by a gauged Schrödinger equation in dimension 2. We are concerned with radial stationary states under the presence of a vortex at the origin. Those states solve a nonlinear nonlocal PDE with a variational structure. We will study the global behavior of that functional, extending known results for the regular case.
Time-dependent singularities in a semilinear parabolic equation with absorption
Authors: Takahashi Jin , Yanagida Eiji
Published: August 2015

This paper concerns solutions with time-dependent singularities for a semilinear parabolic equation with a superlinear absorption term. Here, by time-dependent singularity, we mean a singularity with respect to the space variable whose position depends on time. It is shown that if the power of the nonlinearity is in some range, then any singularity is removable. On the other hand, in other range, two types of time-dependent singular solutions exist: One resembles the fundamental solution of the Laplace equation near the singular point, and the other has a stronger singularity.
Berwald-type and Yano-type connections on Lie algebroids
Authors: Peyghan E.
Published: August 2015

In a new approach, by using the exact sequences, semisprays on the prolongation of a Lie algebroids are introduced and many important results on the semisprays and sprays are obtained. Also, the horizontal endomorphisms, almost complex structures, vertical, horizontal and complete lifts on the prolongation of a Lie algebroid are considered. Then the distinguished connections on the prolongation of a Lie algebroid are introduced and the torsion and curvature tensors of these connections are considered. In particular, the Berwald-type and Yano-type connections are studied.
Surfactant-Assisted Solvothermal Synthesis and High Visible-Light-Induced Photocatalytic Activity of BiOBr Nanocomposite Photocatalyst
Authors: Xu Jing , Tang Guogang , Liang Wei , Zhou Dongyi , Li Changsheng , Tang Hua
Published: August 2015

BiOCl/BiOBr composite microspheres were synthesized through a one-pot mixed surfactant-assisted solvothermal process. The morphology, crystal structure, surface area and photocatalytic activity of the as-prepared BiOCl/BiOBr composite were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-visible diffuse reflectance spectroscopy. The photocatalytic ability of the as-prepared photocatalysts was evaluated using rhodamine B (RhB) as a target pollutant. The BiOCl/BiOBr composite exhibited much higher photocurrent intensity than pure BiOBr, BiOCl and other different components, which perfectly coincided with the enhanced photocatalytic activity for the degradation of RhB under visible light ([Formula: see text][Formula: see text]nm). Moreover, this novel and facile strategy to fabricate bismuth halide-based composite with high efficiency were widely used in other bismuth-based composite photocatalyst for removing organic contaminants in wastewater.
On skew cyclic codes over a semi-local ring
Authors: Ashraf Mohammad , Mohammad Ghulam
Published: August 2015

In the present paper, we study skew cyclic codes over the finite semi-local ring [Formula: see text], where [Formula: see text] and [Formula: see text] is an odd prime. We define a Gray map from [Formula: see text] to [Formula: see text] and investigate the structural properties of skew cyclic codes over [Formula: see text] using decomposition method. It is proved that the Gray image of a skew cyclic code of length [Formula: see text] over [Formula: see text] is a skew [Formula: see text]-quasi-cyclic code of length [Formula: see text] over [Formula: see text]. Further, it is shown that the skew cyclic codes over [Formula: see text] are principally generated.
Are Direct Investments by the Federal Reserve a Good Idea? A Corporate Finance Perspective
Authors: Chen Hong , Frank Murray
Published: August 2015

Due to the crisis of 2007–2009, financial friction macro models are being used to provide a theoretical foundation for the evaluation of ‘unconventional policy’. In these models, banks take deposits from households and lend to firms. Empirically, other financial channels that are missing in the models, such as corporate bonds and equity, are also important. This paper analyzes a model in which bank loans and equity are both feasible. Households have limited ability to enforce their claims. If either the bank or the equity market are undistorted, the equilibrium is socially efficient. If both are distorted, the equilibrium is inefficient. In that case, government policy aimed at the bank or at the firm can be helpful. Suitably chosen equity injections, loans, or interest rate subsidies can all work. Interest rate subsidies have the advantage that they occur later and there is less concern about cheating. Equity injections have the advantage that they minimize the necessary level of tax imposed on households that is needed to achieve optimality. Optimal equity injections and optimal loan subsidies induce reductions in household savings (‘crowding out’). Optimal interest rate subsidies induce increases in household savings (‘crowding in’).
On the categorization of scientific citation profiles in computer science
Authors: Chakraborty Tanmoy , Kumar Suhansanu , Goyal Pawan , Ganguly Niloy , Mukherjee Animesh
Published: August 2015

A new dynamic growth model reveals how citation networks evolve over time, pointing the way toward reformulated scientometrics.
Segmentation of Discriminative Patches in Human Activity Video
Authors: Zhang Bo , Conci Nicola , De Natale Francesco G.B.
Published: August 2015

In this article, we present a novel approach to segment discriminative patches in human activity videos. First, we adopt the spatio-temporal interest points (STIPs) to represent significant motion patterns in the video sequence. Then, nonnegative sparse coding is exploited to generate a sparse representation of each STIP descriptor. We construct the feature vector for each video by applying a two-stage sum-pooling and
l
2
-normalization operation. After training a multi-class classifier through the error-correcting code SVM, the discriminative portion of each video is determined as the patch that has the highest confidence while also being correctly classified according to the video category. Experimental results show that the video patches extracted by our method are more separable, while preserving the perceptually relevant portion of each activity.
Natural language translation at the intersection of AI and HCI
Authors: Green Spence , Heer Jeffrey , Manning Christopher D.
Published: August 2015

Old questions being answered with both AI and HCI.
Moving beyond the cold war
Authors: Arquilla John
Published: August 2015

The
Communications
Web site, http://cacm.acm.org, features more than a dozen bloggers in the BLOG@CACM community. In each issue of
Communications
, we'll publish selected posts or excerpts.

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Follow us on Twitter at http://twitter.com/blogCACM

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John Arquilla assesses the need for cyber arms control.
New news aggregator apps
Authors: Kugler Logan
Published: August 2015

How apps like Inkl and SmartNews are overcoming the challenges of aggregation to win over content publishers and users alike.
Q&A: A Passion for Pairings
Authors: Hoffmann Leah
Published: August 2015

Dan Boneh on pairing-based cryptography, multilinear maps, and how an 1,800-year-old "intellectual curiosity" became the foundation of all secure network traffic.
QoE-Based Cross-Layer Optimization for Uplink Video Transmission
Authors: El Essaili Ali , Wang Zibin , Steinbach Eckehard , Zhou Liang
Published: August 2015

We study the problem of resource-efficient uplink distribution of user-generated video content over fourth-generation mobile networks. This is challenged by (1) the capacity-limited and time-variant uplink channel, (2) the resource-hungry upstreamed videos and their dynamically changing complexity, and (3) the different playout times of the video consumers. To address these issues, we propose a systematic approach for quality-of-experience (QoE)-based resource optimization and uplink transmission of multiuser generated video content. More specifically, we present an analytical model for distributed scalable video transmission at the mobile producers which considers these constraints. This is complemented by a multiuser cross-layer optimizer in the mobile network which determines the transmission capacity for each mobile terminal under current cell load and radio conditions. Both optimal and low-complexity solutions are presented. Simulation results for LTE uplink transmission show that significant gains in perceived video quality can be achieved by our cross-layer resource optimization scheme. In addition, the distributed optimization at the mobile producers can further improve the user experience across the different types of video consumers.
User Preferences Modeling and Learning for Pleasing Photo Collage Generation
Authors: Bianco Simone , Ciocca Gianluigi
Published: August 2015

In this article, we consider how to automatically create pleasing photo collages created by placing a set of images on a limited canvas area. The task is formulated as an optimization problem. Differently from existing state-of-the-art approaches, we here exploit subjective experiments to model and learn pleasantness from user preferences. To this end, we design an experimental framework for the identification of the criteria that need to be taken into account to generate a pleasing photo collage. Five different thematic photo datasets are used to create collages using state-of-the-art criteria. A first subjective experiment where several subjects evaluated the collages, emphasizes that different criteria are involved in the subjective definition of pleasantness. We then identify new global and local criteria and design algorithms to quantify them. The relative importance of these criteria are automatically learned by exploiting the user preferences, and new collages are generated. To validate our framework, we performed several psycho-visual experiments involving different users. The results shows that the proposed framework allows to learn a novel computational model which effectively encodes an inter-user definition of pleasantness. The learned definition of pleasantness generalizes well to new photo datasets of different themes and sizes not used in the learning. Moreover, compared with two state-of-the-art approaches, the collages created using our framework are preferred by the majority of the users.
Automated education and the professional
Authors: Denning Peter J.
Published: August 2015

Technology boffins argue the new technologies of intelligent personal learning environments will put universities out of business. Will the purported successor, an automated global virtual university, be up to the task of professional education?
The pros and cons of the 'PACM' proposal
Authors: McKinley Kathryn S.
Published: August 2015

On p. 5 of this issue, ACM Publications Board co-chairs Joseph A. Konstan and Jack W. Davidson introduce a proposal that would interweave conference and journal publishing. Here, computer scientists Kathryn S. McKinley and David S. Rosenblum argue for and against the proposal.
HeteroVisor
Authors: Gupta Vishal , Lee Min , Schwan Karsten
Published: August 2015

This paper presents HeteroVisor, a heterogeneity-aware hypervisor, that exploits resource heterogeneity to enhance the elasticity of cloud systems. Introducing the notion of 'elasticity' (E) states, HeteroVisor permits applications to manage their changes in resource requirements as state transitions that implicitly move their execution among heterogeneous platform components. Masking the details of platform heterogeneity from virtual machines, the E-state abstraction allows applications to adapt their resource usage in a fine-grained manner via VM-specific 'elasticity drivers' encoding VM-desired policies. The approach is explored for the heterogeneous processor and memory subsystems evolving for modern server platforms, leading to mechanisms that can manage these heterogeneous resources dynamically and as required by the different VMs being run. HeteroVisor is implemented for the Xen hypervisor, with mechanisms that go beyond core scaling to also deal with memory resources, via the online detection of hot memory pages and transparent page migration. Evaluation on an emulated heterogeneous platform uses workload traces from real-world data, demonstrating the ability to provide high on-demand performance while also reducing resource usage for these workloads.
GPUswap
Authors: Kehne Jens , Metter Jonathan , Bellosa Frank
Published: August 2015

Over the last few years, GPUs have been finding their way into cloud computing platforms, allowing users to benefit from the performance of GPUs at low cost. However, a large portion of the cloud's cost advantage traditionally stems from oversubscription: Cloud providers rent out more resources to their customers than are actually available, expecting that the customers will not actually use all of the promised resources. For GPU memory, this oversubscription is difficult due to the lack of support for demand paging in current GPUs. Therefore, recent approaches to enabling oversubscription of GPU memory resort to software scheduling of GPU kernels -- which has been shown to induce significant runtime overhead in applications even if sufficient GPU memory is available -- to ensure that data is present on the GPU when referenced.

In this paper, we present GPUswap, a novel approach to enabling oversubscription of GPU memory that does not rely on software scheduling of GPU kernels. GPUswap uses the GPU's ability to access system RAM directly to extend the GPU's own memory. To that end, GPUswap transparently relocates data from the GPU to system RAM in response to memory pressure. GPUswap ensures that all data is permanently accessible to the GPU and thus allows applications to submit commands to the GPU directly at any time, without the need for software scheduling. Experiments with our prototype implementation show that GPU applications can still execute even with only 20 MB of GPU memory available. In addition, while software scheduling suffers from permanent overhead even with sufficient GPU memory available, our approach executes GPU applications with native performance.
Improving Remote Desktopping Through Adaptive Record/Replay
Authors: Jaffer Shehbaz , Kedia Piyus , Bansal Sorav
Published: August 2015

Accessing the display of a computer remotely, is popularly called remote desktopping. Remote desktopping software installs at both the user-facing client computer and the remote server computer; it simulates user's input events at server, and streams the corresponding display changes to client, thus providing an illusion to the user of controlling the remote machine using local input devices (e.g., keyboard/mouse). Many such remote desktopping tools are widely used. We show that if the remote server is a virtual machine (VM) and the client is reasonably powerful (e.g., current laptop and desktop grade hardware), VM deterministic replay capabilities can be used adaptively to significantly reduce the network bandwidth consumption and server-side CPU utilization of a remote desktopping tool. We implement these optimizations in a tool based on Qemu/KVM virtualization platform and VNC remote desktopping platform. Our tool reduces VNC's network bandwidth consumption by up to 9x and server-side CPU utilization by up to 56% for popular graphics-intensive applications. On the flip side, our techniques consume higher CPU/memory/disk resources at the client. The effect of our optimizations on user-perceived latency is negligible.
IL-1β reciprocally regulates chemokine and insulin secretion in pancreatic β-cells via NF-κB
Authors: Burke Susan J. , Stadler Krisztian , Lu Danhong , Gleason Evanna , Han Anna , Donohoe Dallas R. , Rogers Richard C. , Hermann Gerlinda E. , Karlstad Michael D. , Collier J. Jason
Published: August 2015

Proinflammatory cytokines impact islet β-cell mass and function by altering the transcriptional activity within pancreatic β-cells, producing increases in intracellular nitric oxide abundance and the synthesis and secretion of immunomodulatory proteins such as chemokines. Herein, we report that IL-1β, a major mediator of inflammatory responses associated with diabetes development, coordinately and reciprocally regulates chemokine and insulin secretion. We discovered that NF-κB controls the increase in chemokine transcription and secretion as well as the decrease in both insulin secretion and proliferation in response to IL-1β. Nitric oxide production, which is markedly elevated in pancreatic β-cells exposed to IL-1β, is a negative regulator of both glucose-stimulated insulin secretion and glucose-induced increases in intracellular calcium levels. By contrast, the IL-1β-mediated production of the chemokines CCL2 and CCL20 was not influenced by either nitric oxide levels or glucose concentration. Instead, the synthesis and secretion of CCL2 and CCL20 in response to IL-1β were dependent on NF-κB transcriptional activity. We conclude that IL-1β-induced transcriptional reprogramming via NF-κB reciprocally regulates chemokine and insulin secretion while also negatively regulating β-cell proliferation. These findings are consistent with NF-κB as a major regulatory node controlling inflammation-associated alterations in islet β-cell function and mass.
Role played by NaV 1.7 channels on thin-fiber muscle afferents in transmitting the exercise pressor reflex
Authors: Stone Audrey J. , Copp Steven W. , Kaufman Marc P.
Published: August 2015

Voltage-gated sodium channels (NaV) 1.7 are highly expressed on the axons of somatic afferent neurons and are thought to play an important role in the signaling of inflammatory pain. NaV 1.7 channels are classified as tetrodotoxin (TTX)-sensitive, meaning that they are blocked by TTX concentrations of less than 300 nM. These findings prompted us to determine in decerebrated, unanesthetized rats, the role played by NaV 1.7 channels in the transmission of muscle afferent input evoking the exercise pressor reflex. We first showed that the exercise pressor reflex, which was evoked by static contraction of the triceps surae muscles, was reversibly attenuated by application of 50 nM TTX, but not 5 nM TTX, to the L4-L5 dorsal roots (control: 21 ± 1 mmHg, TTX: 8 ± 2 mmHg, recovery: 21 ± 3 mmHg; n = 6; P < 0.01). We next found that the peak pressor responses to contraction were significantly attenuated by dorsal root application of 100 nM Ssm6a, a compound that is a selective NaV 1.7 channel inhibitor. Removal of Ssm6a restored the reflex to its control level (control: 19 ± 3 mmHg, Ssm6a: 10 ± 1 mmHg, recovery: 19 ± 4 mmHg; n = 6; P < 0.05). Compound action potentials recorded from the L4 and L5 dorsal roots and evoked by single-pulse stimulation of the sciatic nerve showed that both TTX and Ssm6a attenuated input from group III, as well as group IV afferents. We conclude that NaV 1.7 channels play a role in the thin-fiber muscle afferent pathway evoking the exercise pressor reflex.
An Improved Infrared/Visible Fusion for Astronomical Images
Authors: Ahmad Attiq , Riaz Muhammad Mohsin , Ghafoor Abdul , Zaidi Tahir
Published: August 2015

An undecimated dual tree complex wavelet transform (UDTCWT) based fusion scheme for astronomical visible/IR images is developed. The UDTCWT reduces noise effects and improves object classification due to its inherited shift invariance property. Local standard deviation and distance transforms are used to extract useful information (especially small objects). Simulation results compared with the state-of-the-art fusion techniques illustrate the superiority of proposed scheme in terms of accuracy for most of the cases.
Equilibrium Customer Strategies in the Queue with Threshold Policy and Setup Times
Authors: Chen Peishu , Zhou Wenhui , Zhou Yongwu
Published: August 2015

We consider the equilibrium behavior of customers in theM/M/1queue withNpolicy and setup times. The server is shut down once the system is empty and begins an exponential setup time to start service again when the number of customers in the system accumulates the thresholdN  (N≥1). We consider the equilibrium threshold strategies for fully observable case and mixed strategies for fully unobservable case, respectively. We get various performance measures of the system and investigate some numerical examples of system size, social benefit, and expected cost function per unit time for the two different cases under equilibrium customer strategies.
Preparation of Mesoporous Silica‐Supported Chiral Amino Alcohols for the Enantioselective Addition of Diethylzinc to Aldehyde and Asymmetric Transfer Hydrogenation to Ketones
Authors: Sarkar Shaheen M. , Ali Md. Eaqub , Rahman Md. Lutfor , Mohd Yusoff Mashitah
Published: August 2015

Optically active (−)‐ephedrine, (−)‐norephedrine, and (−)‐prolinol were immobilized onto cubic mesoporous MCM‐48 silica. The immobilized amino alcohols served as a heterogeneous chiral catalyst for the asymmetric addition of diethylzinc to aldehydes and transfer hydrogenation to ketones. The developed catalytic process yielded optically enriches secondary aromatic alcohols with 92–99% conversion and 70–82% enantioselectivity.
Device Nimbus: An Intelligent Middleware for Smarter Services for Health and Fitness
Authors: Oliveira Eduardo Araujo , Kirley Michael , Fonseca Jorge C. B. , Gama Kiev
Published: August 2015

The world is experiencing an unprecedented explosion in the number of smart devices and mobile apps that are available to users. In the health and fitness domains, many of the devices and technologies in the market place are restricted to proprietary platforms, typically working in isolation with fixed hardware settings. Consequently, an important challenge is to investigate techniques for combining and analyzing data encapsulated by these ubiquitous technologies. In this paper, we introduce an intelligent middleware—Device Nimbus—to meet this challenge. The middleware supports the integration of distributed and heterogeneous mobile sensor data, enabling both context and predictive analysis. We describe a minimum viable product of Device Nimbus and report the results of preliminary tests spanning multiple data sources focused on fitness apps, illustrating the efficacy of the middleware.
Maintaining Track Continuity for Extended Targets Using Gaussian-Mixture Probability Hypothesis Density Filter
Authors: Han Yulan , Zhu Hongyan , Han ChongZhao
Published: August 2015

A multiextended-target tracker based on the extended target Gaussian-mixture probability hypothesis density (ET-GMPHD) filter, which can provide the tracks of the extended targets, is proposed to maintain the track continuity for the extended targets. To identify the extended targets, each individual Gaussian term of the mixture representing the posterior intensity function will be assigned a label, which is evolved through time. Then a track management scheme, including track initiation, track confirmation, track propagation, and termination, is developed to form the tracks for the extended targets. Furthermore, to improve the performance of the extended target tracker we also propose a mixture partitioning algorithm for resolving the identities of the extended targets in close proximity. The simulation results show that our proposed tracker achieves the less error of the position estimates and decreases the probability of incorrect label assignments from 0.6 to 0.25.
When Intervention Meets Organisation, a Qualitative Study of Motivation and Barriers to Physical Exercise at the Workplace
Authors: Bredahl Thomas Viskum Gjelstrup , Særvoll Charlotte Ahlgren , Kirkelund Lasse , Sjøgaard Gisela , Andersen Lars Louis
Published: August 2015

Objective. To provide a comprehensive understanding of the motivational factors and barriers that are important for compliance with high‐intensity workplace physical exercise that is aimed at reducing musculoskeletal disorders. Method. The present study, which used semideductive, thematic, and structured in‐depth interviews, was nested in a 20‐week cluster randomised controlled trial among office workers. Interviews were conducted with 18 informants with diverse fields of sedentary office work who participated in strength training at the workplace for 20 minutes, three times per week. Organisational, implementational, and individual motives and barriers were explored. Results & Discussion. The results show that attention should be given to the interaction between the management, the employees, and the intervention, as the main barrier to compliance was the internal working culture. The results emphasised the need for a clear connection between the management’s implementational intentions and the actual implementation. The results emphasise the importance of ensuring the legitimacy of the intervention among managers, participants, and colleagues. Moreover, it is important to centrally organise, structure, and ensure flexibility in the working day to free time for participants to attend the intervention. Recommendations from this study suggest that a thorough intervention mapping process should be performed to analyse organisational and implementational factors before initiating workplace physical exercise training.
Primary Mesenteric Undifferentiated Pleomorphic Sarcoma Masquerading as a Colon Carcinoma: A Case Report and Review of the Literature
Authors: Diaz-Beveridge Robert , Melian Marcos , Zac Carlos , Navarro Edwin , Akhoundova Dilara , Chrivella Melitina , Aparicio Jorge
Published: August 2015

Undifferentiated pleomorphic sarcoma (UPS) is the most common sarcoma that appears in older patients, usually in the extremities and the retroperitoneum. Other locations are rare. By definition, in UPS, although the malignant cells tend to appear fibroblastic or myofibroblastic, they should not show differentiation towards a more specific line of differentiation. In this sense, we report the case of an 80-year-old patient with an initial clinical diagnosis of a locally advanced colonic neoplasm that was later confirmed as a primary mesenteric UPS. Primary mesenteric UPS are extremely rare with less than 20 cases reported. We also review the pathologic and radiologic diagnostic criteria and the natural history of these tumours.