bluuebunny/crossref_metadata_2025 huggingface dataset:
Calcium‐activated BKCa channels govern dynamic membrane depolarizations of horizontal cells in rodent retina
Authors: Sun Xiaoping , Hirano Arlene A. , Brecha Nicholas C. , Barnes Steven
Published: April 2017

Key points

Large conductance, Ca2+‐activated K+ (BKCa) channels play important roles in mammalian retinal neurons, including photoreceptors, bipolar cells, amacrine cells and ganglion cells, but they have not been identified in horizontal cells.

BKCa channel blockers paxilline and iberiotoxin, as well as Ca2+ free solutions and divalent cation Cav channel blockers, eliminate the outwardly rectifying current, while NS1619 enhances it. In symmetrical 150 mm K+, single channels had a conductance close to 250 pS, within the range of all known BKCa channels.

In current clamped horizontal cells, BKCa channels subdue depolarizing membrane potential excursions, reduce the average resting potential and decrease oscillations. The results show that BKCa channel activation puts a ceiling on horizontal cell depolarization and regulates the temporal responsivity of the cells.

Large conductance, calcium‐activated potassium (BKCa) channels have numerous roles in neurons including the regulation of membrane excitability, intracellular [Ca2+] regulation, and neurotransmitter release. In the retina, they have been identified in photoreceptors, bipolar cells, amacrine cells and ganglion cells, but have not been conclusively identified in mammalian horizontal cells. We found that outward current recorded between −30 and +60 mV is carried primarily in BKCa channels in isolated horizontal cells of rats and mice. Whole‐cell outward currents were maximal at +50 mV and declined at membrane potentials positive to this value. This current was eliminated by the selective BKCa channel blocker paxilline (100 nm), iberiotoxin (10 μm), Ca2+ free solutions and divalent cation Cav channel blockers. It was activated by the BKCa channel activator NS1619 (30 μm). Single channel recordings revealed the conductance of the channels to be 244 ± 11 pS (n = 17; symmetrical 150 mm K+) with open probability being both voltage‐ and Ca2+‐dependent. The channels showed fast activation kinetics in response to Ca2+ influx and inactivation gating that could be modified by intracellular protease treatment, which suggests β subunit involvement. Under current clamp, block of BKCa current increased depolarizing membrane potential excursions, raising the average resting potential and producing oscillations. BKCa current activation with NS1619 inhibited oscillations and hyperpolarized the resting potential. These effects underscore the functional role of BKCa current in limiting depolarization of the horizontal cell membrane potential and suggest actions of these channels in regulating the temporal responsivity of the cells.
How do horizontal cells ‘talk’ to cone photoreceptors? Different levels of complexity at the cone–horizontal cell synapse
Authors: Chapot Camille A. , Euler Thomas , Schubert Timm
Published: April 2017

The first synapse of the retina plays a fundamental role in the visual system. Due to its importance, it is critical that it encodes information from the outside world with the greatest accuracy and precision possible. Cone photoreceptor axon terminals contain many individual synaptic sites, each represented by a presynaptic structure called a ‘ribbon’. These synapses are both highly sophisticated and conserved. Each ribbon relays the light signal to one ON cone bipolar cell and several OFF cone bipolar cells, while two dendritic processes from a GABAergic interneuron, the horizontal cell, modulate the cone output via parallel feedback mechanisms. The presence of these three partners within a single synapse has raised numerous questions, and its anatomical and functional complexity is still only partially understood. However, the understanding of this synapse has recently evolved, as a consequence of progress in understanding dendritic signal processing and its role in facilitating global versus local signalling. Indeed, for the downstream retinal network, dendritic processing in horizontal cells may be essential, as they must support important functional operations such as contrast enhancement, which requires spatial averaging of the photoreceptor array, while at the same time preserving accurate spatial information. Here, we review recent progress made towards a better understanding of the cone synapse, with an emphasis on horizontal cell function, and discuss why such complexity might be necessary for early visual processing.

image
Sensitivity to ischaemia of single sympathetic nerve fibres innervating the dorsum of the human foot
Authors: Z'Graggen W. J. , Solà R. , Graf N. E. , Serra J. , Bostock H.
Published: April 2017

Key points

Changes in nerve conduction velocity following an impulse (i.e. velocity recovery cycles) reflect after‐potentials, and can provide an indication of altered nerve membrane properties.

This study used microneurography to assess the effects of ischaemia on single human sympathetic fibres innervating the dorsum of the foot.

It was found that velocity recovery cycles can distinguish whether a sympathetic nerve fibre is depolarized or not.

The method may be used to detect membrane depolarization of sympathetic nerve fibres in human patients when autonomic neuropathy is suspected.

The aim of this study was to determine whether velocity recovery cycles (VRCs) could detect the effects of ischaemia on sympathetic nerve fibres. VRCs of human sympathetic nerve fibres of the superficial peroneal nerve innervating the dorsum of the foot were recorded by microneurography in seven healthy volunteers. Sympathetic nerve fibres were identified by studying their response to manoeuvres increasing sympathetic outflow and by measuring activity‐dependent slowing at 2 Hz stimulation. VRCs were assessed at rest, during 30 min of induced limb ischaemia and during 20 min of recovery after ischaemia. From each VRC was measured the relative refractory period (RRP), the supernormality and the time to peak supernormality (SN@). During ischaemia, RRP increased from the baseline value of 37.4 ± 8.7 ms (mean ± SEM) to 67.1 ± 12.1 ms (P < 0.01) and SN@ increased from 68.6 ± 9.8 ms to 133.8 ± 11.0 ms (P < 0.005). The difference between SN@ and RRP separated ischaemic from non‐ischaemic sympathetic nerve fibres. It is concluded that these sympathetic nerve fibres are sensitive to ischaemia, and that VRCs provide a method to study changes of axonal membrane potential of human sympathetic nerve fibres in vivo.
Global Research Collaboration and International Education: Laser Metal Deposition of Varying Percent of Ti-6Al-4V + Molybdenum on Ti64 Substrate for Biomedical/Aerospace Applications
Authors: Kumpaty Subha , Akinlabi Esther , Reynolds Christopher , Mueller Robert , Pityana Sisa
Published: April 2017

This paper presents the characterization studies conducted by Milwaukee School of Engineering senior undergraduate students in South Africa under the Research Experiences for Undergraduates grant EEC-1460183 sponsored by the National Science Foundation (Principal Investigator Dr. Kumpaty). Robert Mueller and Christopher Reynolds conducted research in summer of 2015 under advisement of Dr. Kumpaty and his South African collaborators, Dr. Esther Akinlabi and Dr. Sisa Pityana. The foreign collaborators’ excellent support was pivotal to the success of our U.S. students.

Ti-6 Al-4 V is a titanium alloy that accounts for about 80% of the titanium market. The Ti-64 alloy contains 6 wt% Aluminum and 4 wt% Vanadium, an almost equal ratio of α + β phases. Through the laser surface modification process known as Laser Meal Deposition, this alloy offers the optimum combination of enhanced properties. This research focuses on the application of adding a combination of molybdenum (Mo) and Ti-64 powders to a Ti-64 substrate surface in order to improve the durability for various biomedical/aerospace applications. Deposition of the powders was completed at the CSIR - National Laser Center, in Pretoria, South Africa. The characterization studies were carried out at the University of Johannesburg. The results of the hardness tests showed that the addition of molybdenum to Ti-64 increased the hardness of the deposited material compared to that of the substrate. This verifies that the addition of Mo to metals can affect the mechanical properties to better suit various applications.

While Robert Mueller studied the effect of laser power on the properties of laser metal deposited Ti-6Al-4V + Mo for wear resistance enhancement, Christopher Reynolds investigated scanning velocity influence on the evolving properties of laser metal deposited Ti-6Al-4V + Mo. The results of this promising research and various options for further investigation are presented. The beneficial value of such a global research enterprise on the budding engineers will be apparent and the paper details the process of the international component of the Research Experiences for Undergraduates.
Design and Fabrication of a Self-Cleaning Toilet: Developing a Student Invention
Authors: Maric Stephan , Phelps Joey , Bzymek Zbigniew M. , Moreno Vito
Published: April 2017

The University of Connecticut Senior Design Capstone course developed by the Department of Mechanical Engineering is widely recognized by the Connecticut industry. The course provides fourth year students the opportunity for a major design experience in which they apply principles of engineering staring with the conceptual design through the basic science and mathematics, up to model, analysis, design of physical systems its components or processes as well as prepares students to work professionally [9]. This paper will discuss the issues and challenges associated with one of the Senior Design (SD) projects that was based on student generated inventive concept and sponsored by the student-inventor. The project demonstrated the design and prototyping problems on the example so called “Self-Cleaning Toilet”. The project addresses “self-cleaning” of facilities where infectious bacteria and viruses are prevalent in frequently used installations such as public restrooms. These areas tend to be difficult to keep clean often, without obstructing the functionality of the facility. The solution being proposed in this project is an intelligently designed, self-regulating, cleaning system that is able to be retroactively fitted onto a variety of toilet seats.

UV germicidal irradiation was chosen as the primary method to eliminate germs for this device for several reasons. Using a UV light allows for more efficient, effortless elimination of germs as compared to conventional cleaning methods. The light encourages hands off operation, meaning that the user will not have to physically touch the toilet seat to clean it. Additionally, it allows the toilet seat surface to be cleaned continually throughout the day and in between uses, which is an unrealistic task to replicate with methods currently being employed.

Multiple experiments were conducted that tested the ability of the UV light to reach all surfaces on a toilet seat. The germicidal effectiveness experiment tested the sanitation capability of the light under its intended operating conditions. Finally, the durability test indicated that the device would be able to withstand the conditions of the working environments commonly associated with bathrooms. Designs, building and testing of the prototype of such a toilet seat are described in the paper. Results from each of the testing experiments and experience gained in the creation of the Clean Light toilet design are described in the paper.
A Flipped Classroom Approach to Conveying the Basics of Systems Thinking to Engineering Undergraduates
Authors: Weaver Jonathan M. , Kleinke Darrell K.
Published: April 2017

Engineering students spend the majority of their academic careers learning tools to enable tasks related to detailed design. For example, a mechanical engineer may learn to size a heat exchanger so that an engine would not overheat, an electrical engineer may learn to specify gains in a control system to provide desired performance, and a civil engineer may learn to size columns to avoid buckling. While these analytical capabilities are essential to the execution of engineered systems, there are tools and perspectives related to systems and their design that are historically absent in an undergraduate engineering education. Through the Kern Entrepreneurship Education Network (KEEN) and the University of New Haven, the authors have developed a flipped classroom module that provides a basis in systems thinking as related to the conception and execution of complex engineered systems. The module could be useful in several areas of the curriculum, but is primarily intended to develop perspectives and skills necessary to ensure a successful capstone design experience.

The module is broken into five lessons: (1) Foundational Concepts, (2) Key Systems Principles, (3) Architecture Development, (4) Multiple Views of a System, and (5) System Verification and Validation. Lesson 1 begins with the importance of the problem statement, and then proceeds to introduce form and function, function mapping, and many key definitions (system, interface, architecture, systems engineering, and complexity). Lesson 2 introduces key systems principles, including systems thinking, systems of systems, and system decomposition. Lesson 3 overviews the systems architecting process and summarizes the four most typical methods used to develop a system architecture. Lesson 4 discusses viewing a system from six different perspectives. Lesson 5 presents the systems engineering V model, requirements cascading, and verification and validation.

The module includes several interactive activities and built in knowledge checkpoints. There is also a final challenge wherein the students must apply what they’ve learned about systems thinking and systems engineering to a hypothetical problem.

This paper will further describe the module content and format. The paper will also make the case that the content included in the module is essential to an efficient, effective, and rewarding capstone design experience. This is achieved by summarizing common pitfalls that occur in a capstone design project and how good systems thinking can avert them. The pitfalls covered include failure to fully understand all key stakeholders’ most important needs, failure to understand desired system function in a solution-neutral way and failure to follow a robust process to map function to form, poor choice of how to decompose the system into subsystems, errors/inefficiencies in interface definition and management, and poor (if any) planning for design verification and validation.
Increasing Student Awareness of Non-Traditional Career Paths in Mechanical Engineering
Authors: Huang Shaobo , Degen Cassandra M. , Muci-Kuchler Karim H. , Ellingsen Marius D.
Published: April 2017

This paper reports the effect of the curriculum changes in the Mechanical Engineering (ME) department at the South Dakota School of Mines and Technology (SDSM&T) in two freshman courses. Besides introducing fundamental concepts and principles for mechanical engineering, these courses utilize guest speaker sections to introduce career opportunities, and integrate marketing and corporate policy into engineering design projects.

An engineering motivation survey and a career awareness questionnaire were developed and employed to better understand the impact of the new curriculum on students’ attitudes toward and desire to persist in Mechanical Engineering. Freshmen students’ intrinsic and extrinsic motivations and career awareness were assessed in pre- and post-tests at the beginning and the end of a semester.

The results obtained showed that the introduction of the non-traditional career paths into the two courses students’ perceptions of the career options that ME graduates can pursue and showcased alternatives that proved to be more attractive to under-represented (female) students. Although the students spent less time in traditional engineering topics, their engineering self-efficacy was not diminished, and in fact, the students’ intrinsic motivation was significantly improved. Additionally, students perceived stronger inclusion in the ME program.
Self-Efficacy Analysis of Student Learning in Systems Engineering
Authors: Khan Rabia , Whitcomb Cliff , White Corina
Published: April 2017

Systems engineering (SE) competencies are defined based on the knowledge, skills, and abilities (KSAs) necessary for a systems engineer to perform tasks related to the discipline. Proficient systems engineers are expected to be able to integrate, apply, and be assessed on these KSAs as they develop competencies through their education and training, professional development, and on-the-job experience. The research conducted by the Naval Postgraduate School assessed where SE graduate students stood as far as developing the necessary competency levels they need to be successful systems engineers. A survey methodology was used to achieve this objective. Systems engineering students enrolled in SE courses at the Naval Postgraduate School represented the population surveyed.

Survey items were written with the intent to capture self-efficacy for knowledge and skill sets as a subset of the overall set of competencies required for systems engineering, namely within the SE competencies of Critical Thinking, Systems Engineering, Teamwork and Project Management. A total of four surveys were administered to two SE cohorts. Results show that self-efficacy in systems engineering can be reasonably assumed to be positively affected by a graduate level educational program. The implications of the research can be used to develop structured curriculum content, assessment, and continuous process improvement techniques related to the development of SE learning, and to develop more valid and reliable instruments for assessing what systems engineers need to learn, need to know, and need to do.
Higher Education Makerspaces and Engineering Education
Authors: Wilczynski Vincent , Adrezin Ronald
Published: April 2017

While originating in non-academic settings, the “Maker Movement” has quickly made inroads within academia. More significant than the facility that may be referred to as a makerspace is the makerspace culture, including the community that forms around the physical facility and the activities (programs) of that community. This paper reviews the history of the maker-phenomenon, details the development of higher education makerspace cultures over the last five years, and explores the impact of makerspace cultures on mechanical engineering education. The makerspace culture at two higher education institutions is used to illustrate the effect on engineering education within each institution. The paper concludes with a review of common practices within the higher education makerspace ecosystem.
Bactericidal Permeability-Increasing Proteins Shape Host-Microbe Interactions
Authors: Chen Fangmin , Krasity Benjamin C. , Peyer Suzanne M. , Koehler Sabrina , Ruby Edward G. , Zhang Xiaoping , McFall-Ngai Margaret J.
Published: April 2017

We characterized bactericidal permeability-increasing proteins (BPIs) of the squid
Euprymna scolopes
, EsBPI2 and EsBPI4. They have molecular characteristics typical of other animal BPIs, are closely related to one another, and nest phylogenetically among invertebrate BPIs. Purified EsBPIs had antimicrobial activity against the squid’s symbiont,
Vibrio fischeri
, which colonizes light organ crypt epithelia. Activity of both proteins was abrogated by heat treatment and coincubation with specific antibodies. Pretreatment under acidic conditions similar to those during symbiosis initiation rendered
V. fischeri
more resistant to the antimicrobial activity of the proteins. Immunocytochemistry localized EsBPIs to the symbiotic organ and other epithelial surfaces interacting with ambient seawater. The proteins differed in intracellular distribution. Further, whereas EsBPI4 was restricted to epithelia, EsBPI2 also occurred in blood and in a transient juvenile organ that mediates hatching. The data provide evidence that these BPIs play different defensive roles early in the life of
E. scolopes
, modulating interactions with the symbiont.

IMPORTANCE
This study describes new functions for bactericidal permeability-increasing proteins (BPIs), members of the lipopolysaccharide-binding protein (LBP)/BPI protein family. The data provide evidence that these proteins play a dual role in the modulation of symbiotic bacteria. In the squid-vibrio model, these proteins both control the symbiont populations in the light organ tissues where symbiont cells occur in dense monoculture and, concomitantly, inhibit the symbiont from colonizing other epithelial surfaces of the animal.
Can visible signs predict concussion diagnosis in the National Hockey League?
Authors: Echemendia Ruben J , Bruce Jared M , Meeuwisse Willem , Hutchison Michael G , Comper Paul , Aubry Mark
Published: April 2017

Background

Early identification and evaluation of concussions is critical. We examined the utility of using visible signs (VS) of concussion in predicting subsequent diagnosis of concussion in NHL players.

Methods

VS of concussion were identified through video review. Coders were trained to detect and record specific visual signs while viewing videos of NHL regular season games. 2460 games were reviewed by at least two independent coders across two seasons. The reliability, sensitivity and specificity of these VS were examined.

Results

VS were reliably coded with inter-rater agreement rates ranging from 73% to 98.9%. 1215 VS were identified in 861 events that occurred in 735 games. 47% of diagnosed concussions were associated with a VS but 53% of diagnosed concussions had no VS. Of the VS, only loss of consciousness, motor incoordination, and blank/vacant look had positive likelihood ratios greater than 1, indicating a positive association with concussion diagnoses. Slow to get up and clutching of the head were observed frequently but had low positive predictive values. Sensitivity decreased and specificity increased when multiple VS occurred together.

Conclusions

Non-medical personnel can be trained to reliably identify events in which VS occur and to reliably identify specific VS within each of those events. VS can be useful to detect concussion early but they are not enough since more than half of physician diagnosed concussions occurred without the presence of a visual sign. The results underscore the complexity of this injury and highlight the need for comprehensive approaches to injury detection.
Dietary assessment of British police force employees: a description of diet record coding procedures and cross-sectional evaluation of dietary energy intake reporting (The Airwave Health Monitoring Study)
Authors: Gibson Rachel , Eriksen Rebeca , Lamb Kathryn , McMeel Yvonne , Vergnaud Anne-Claire , Spear Jeanette , Aresu Maria , Chan Queenie , Elliott Paul , Frost Gary
Published: April 2017

Objectives

Dietary intake is a key aspect of occupational health. To capture the characteristics of dietary behaviour that is affected by occupational environment that may affect disease risk, a collection of prospective multiday dietary records is required. The aims of this paper are to: (1) collect multiday dietary data in the Airwave Health Monitoring Study, (2) describe the dietary coding procedures applied and (3) investigate the plausibility of dietary reporting in this occupational cohort.

Design

A dietary coding protocol for this large-scale study was developed to minimise coding error rate. Participants (n 4412) who completed 7-day food records were included for cross-sectional analyses. Energy intake (EI) misreporting was estimated using the Goldberg method. Multivariate logistic regression models were applied to determine participant characteristics associated with EI misreporting.

Setting

British police force employees enrolled (2007–2012) into the Airwave Health Monitoring Study.

Results

The mean code error rate per food diary was 3.7% (SD 3.2%). The strongest predictors of EI under-reporting were body mass index (BMI) and physical activity. Compared with participants with BMI<25 kg/m2, those with BMI>30 kg/m2had increased odds of being classified as under-reporting EI (men OR 5.20 95% CI 3.92 to 6.89; women OR 2.66 95% CI 1.85 to 3.83). Men and women in the highest physical activity category compared with the lowest were also more likely to be classified as under-reporting (men OR 3.33 95% CI 2.46 to 4.50; women OR 4.34 95% CI 2.91 to 6.55).

Conclusions

A reproducible dietary record coding procedure has been developed to minimise coding error in complex 7-day diet diaries. The prevalence of EI under-reporting is comparable with existing national UK cohorts and, in agreement with previous studies, classification of under-reporting was biased towards specific subgroups of participants.
Effects of Testosterone and Evoked Resistance Exercise after Spinal Cord Injury (TEREX-SCI): study protocol for a randomised controlled trial
Authors: Gorgey Ashraf S , Khalil Refka E , Gill Ranjodh , O'Brien Laura C , Lavis Timothy , Castillo Teodoro , Cifu David X , Savas Jeannie , Khan Rehan , Cardozo Christopher , Lesnefsky Edward J , Gater David R , Adler Robert A
Published: April 2017

Introduction

Individuals with spinal cord injury (SCI) are at a lifelong risk of obesity and chronic metabolic disorders including insulin resistance and dyslipidemia. Within a few weeks of injury, there is a significant decline in whole body fat-free mass, particularly lower extremity skeletal muscle mass, and subsequent increase in fat mass (FM). This is accompanied by a decrease in anabolic hormones including testosterone. Testosterone replacement therapy (TRT) has been shown to increase skeletal muscle mass and improve metabolic profile. Additionally, resistance training (RT) has been shown to increase lean mass and reduce metabolic disturbances in SCI and other clinical populations.

Methods and analysis

26 individuals with chronic, motor complete SCI between 18 and 50 years old were randomly assigned to a RT+TRT group (n=13) or a TRT group (n=13). 22 participants completed the initial 16-week training phase of the study and 4 participants withdrew. 12 participants of the 22 completed 16 weeks of detraining. The TRT was provided via transdermal testosterone patches (4–6 mg/day). The RT+TRT group had 16 weeks of supervised unilateral progressive RT using surface neuromuscular electrical stimulation with ankle weights. This study will investigate the effects of evoked RT+TRT or TRT alone on body composition (muscle cross-sectional area, visceral adipose tissue, %FM) and metabolic profile (glucose and lipid metabolism) in individuals with motor complete SCI. Findings from this study may help in designing exercise therapies to alleviate the deterioration in body composition after SCI and decrease the incidence of metabolic disorders in this clinical population.

Ethics and dissemination

The study is currently approved by the McGuire VA Medical Center and Virginia Commonwealth University. All participants read and signed approved consent forms. Results will be submitted to peer-reviewed journals and presented at national and international conferences.

Trial registration number

Pre-result,NCT01652040.
Integrated approach of nutritional and molecular epidemiology, mineralogical and chemical pollutant characterisation: the protocol of a cross-sectional study in women
Authors: Barchitta Martina , Quattrocchi Annalisa , Maugeri Andrea , Barone Germana , Mazzoleni Paolo , Catalfo Alfio , De Guidi Guido , Iemmolo Maria , Crimi Nunzio , Agodi Antonella
Published: April 2017

Introduction

Environmentally-related health and disease are the result of the exposome, the totality of a person's environmental exposures, from all sources and routes, across their lifespan. Epigenetic phenomena, including DNA methylation, can be potentially modified by environmental and lifestyle factors, and result in environmental reprogramming of the genome for exposed individuals and for future generations of offspring.

Objective

The objective of the project is to evaluate the risk of DNA hypomethylation due to air pollution, Mediterranean diet adherence, folate intake, and demographic and socioeconomic factors, in healthy women living in the metropolitan area of Catania, Italy.

Methods and analysis

Non-pregnant healthy women will be enrolled in a cross-sectional study. Sociodemographic, lifestyle and dietary intake information will be collected. LINE-1 methylation will be measured by pyrosequencing. The participants' home addresses will be geocoded and each woman will be assigned to the closest monitoring station for particulate matter (PM) exposure assessment. Mineralogical-chemical characterisation of PM and cellular model assays will be performed. An integrated approach will be designed to estimate the combined possible effect of air pollution, Mediterranean diet adherence, folate intake and other lifestyle characteristics on LINE-1 methylation levels.

Ethics and dissemination

The project has been approved by the ethics committees of the involved institution and funded by the University of Catania (Finanziamento della Ricerca, FIR 2014). All participants will be fully informed of the purpose and procedures of the study, and signed written consents will be obtained. All the data collected will be treated confidentially and analysed in an aggregate and anonymous way. The results will be published in peer-reviewed journals and communicated to local public health agencies, in order to provide essential information for timely and effective public health action.
Optimal duration of dual antiplatelet therapy following percutaneous coronary intervention: protocol for an umbrella review
Authors: Elliott Jesse , Kelly Shannon E , Bai Zemin , Liu Wenfei , Skidmore Becky , Boucher Michel , So Derek Y F , Wells George A
Published: April 2017

Introduction

Although dual antiplatelet therapy (DAPT) is routinely given to patients after percutaneous coronary intervention (PCI) with stenting, the optimal duration is unknown. Recent evidence indicates there may be benefits in extending the duration beyond 12 months but such decisions may increase the risk of bleeding. Our objective is to provide a comprehensive overview of the literature for clinicians and policymakers via an umbrella review assessing the optimal duration of DAPT.

Methods and analysis

We will perform a comprehensive search of the published and grey literature for systematic reviews involving randomised controlled trials (RCTs) assessing the optimal duration of DAPT following PCI with stenting. The intervention of interest is extended DAPT (beyond 12 months) compared with short-term DAPT (6–12 months). Studies will be selected for inclusion by two reviewers, and the quality will be assessed. The primary outcomes of interest are all-cause mortality and cardiovascular mortality. Secondary outcomes will be bleeding (major, minor and gastrointestinal), urgent target vessel revascularisation, major adverse cardiovascular events, myocardial infarction, stroke and stent thrombosis. Outcomes will be assessed while on DAPT and after withdrawal of DAPT. Data will be summarised with respect to the number of included RCTs, number of participants, effect estimates and heterogeneity. Data will be reported separately based on patient demographics, procedural parameters (eg, stent types, lesion complexity and concurrent disease) and clinical presentation (eg, acute coronary syndromes, infarct type).

Ethics and dissemination

Our umbrella review aims to provide a comprehensive overview of the benefits and harms associated with extending DAPT beyond 12 months following PCI with stenting. The results of this review will inform clinical and policy decisions regarding the optimal treatment duration and reimbursement of DAPT following PCI with stenting. Results will be disseminated through a peer-reviewed publication and conference presentations. Ethics approval is not required for this study.

Trial registration number

CRD42016047735.
Experiences participating in a community-based exercise programme from the perspective of people living with HIV: a qualitative study
Authors: Montgomery Chantal A , Henning Katherine J , Kantarzhi Sarah R , Kideckel Tamar B , Yang Cheryl F M , O'Brien Kelly K
Published: April 2017

Objectives

Our aim was to explore the experiences of engaging in a community-based exercise programme (CBEP) from the perspective of people living with HIV (PLWH).

Design

We conducted a descriptive qualitative study using semistructured interviews.

Setting

We recruited adults living with HIV who participated in a 16-week CBEP in Toronto, Canada.

Participants

11 participants, the majority men (64%), with a median age of 52 years, and living with a median of 5 concurrent health conditions in addition to HIV participated in the study.

Outcome measures

We asked participants about their overall experiences: strengths, limitations and perceived benefits of the CBEP; factors influencing participation and current level of exercise after completion of the CBEP. We administered a self-reported demographic questionnaire followed by the Rapid Assessment of Physical Activity (RAPA) questionnaire. We analysed interview data using thematic analysis.

Results

We developed a framework that describes the experiences before, during and after the CBEP; and the perceived impact of the CBEP on health, which influenced the intent to, engagement in and sustainability of exercise among PLWH. Participants described the positive impact of the CBEP on their physical, mental and social health. Interviews were completed at a median of 6 months after the CBEP, when 9 participants reported ongoing engagement in exercise, but to a lesser extent than during the CBEP. Intrinsic and extrinsic factors facilitated or hindered engagement in exercise throughout all phases of the CBEP. The episodic nature of HIV and multimorbidity influenced engagement in exercise and posed challenges to re-engagement after periods of inactivity.

Conclusions

CBEPs provide an opportunity to enhance physical activity, perceived health outcomes and knowledge about exercise for PLWH. Community-based exercise is a strategy that may be used by health providers to promote engagement in sustained physical activity for PLWH.
Separation of vanadium(V) using N235 by three-phase system in concentrated HCl media
Authors: Shen Chun , Zhang Yimin , Huang Jing , Bao Shenxu , Yang Xiao , Xiong Pu
Published: April 2017

The third phase formed in the process of extracting vanadium in a N235/HCl system was usually regarded as a limit to the throughput of the plant. To have a deep insight on this problem, the formation of the third phase in the extraction of vanadium by tertiary amine N235 in the concentrated HCl system was studied. The optimum parameters of three-phase system extraction were determined, and FTIR analysis was carried out to characterize the structure of extracted complexes and analyze the mechanism of formation and elimination of the third phase. The results showed that vanadium extraction efficiency was 86.5% with 20% v/v N235 and a phase ratio (O:A) of 1:2 in 2 min at 25 °C, though an obvious third phase was found within the experimental HCl concentration range. Cl− is the participant in the process of increasing the vanadium extraction efficiency, whereas H+ has an inhibitory effect on vanadium extraction. Meanwhile, the structure of the extracted complex was confirmed as (R3N)m(HCl)m+x·([Formula: see text])·(H2O)n through a solvation mechanism with molecular association, which was further proved by FTIR spectral analysis. Furthermore, the limited solubility of the ion-extracted complexes in the nonpolar solvent kerosene made the third-phase form. The third phase disappeared when phase modifier (about 5% v/v TBP) was added into the organic phase, as the polarity of the organic phase increased.
Anti-reflective microstructure array and its performance evaluation in thin film flexible solar cells
Authors: Chen Fei , Zhan Xinghua , Gao Mengyu , Tie Shengnian , Gao Wei
Published: April 2017

The anti-reflective (AR) structure greatly reduces the light reflection. When it is applied on solar cells, it enables more light to be absorbed by the cells, increasing the energy of the incident light and improving the light-to-electricity conversion efficiency. In this study, the optical properties of AR microstructures are investigated followed by the performance evaluation of solar cells. The AR microstructure is arrayed in a uniform and periodic fashion. When it is applied on PMMA, only 1.0% of the light is reflected away while 2.6% of the light is reflected on glass. The angular dependence performance is also improved with AR structure with 9.4% more light absorption, which can increase the effective energy generation duration for the solar cell. The AR structure is applied to amorphous silicon thin film solar cells by nano-imprinting technology. The solar cell with AR structure gained 8.63% more power compared to the conventional solar cells.
Fabricating omnidirectional low-reflection films by nano-imprinting method for boosting solar power generation of silicon-based solar cells
Authors: Gao Mengyu , Zhan Xinghua , Chen Fei , Si Yang , Tie Shengnian , Gao Wei
Published: April 2017

Low-reflection polyethylene terephthalate (PET) films are fabricated with nano-imprinting method. The films are then used to cover polycrystalline silicon solar cells. The morphological and optical properties of films are investigated. The films have periodic cylinder-like nanostructures and relatively low reflectivity in light incident angle ranging from 30[Formula: see text] to 60[Formula: see text]. The nanostructures are with a period of 600 nm and height of 90 nm. Besides, the polycrystalline Si solar cells covered with the films exhibit 12% more power generation than the cells covered with glass. Nano-imprinting method offers a cost-effective approach to fabricate omnidirectional anti-reflection films, which could boost the power generation of Si solar cells. Additionally, the films also have potential applications in different types of solar cells due to its facile fabricating process.
Aluminum electrolytic capacitors for tablet PC
Authors: Liu Longchun , Dong Liangwei , Li Qinglong , Xu Xiangyang
Published: April 2017

Based on the operating conditions of tablet PC, this paper presents the design of a long load life aluminum electrolytic capacitor. Due to the key technology breakthrough of electrolyte with low resistance and excellent temperature stability, the capacitor boasts low leakage current, low impedance, high frequency, high ripple resistance and high temperature resistance. In the meantime, it can pass 5000 h of durability test with load at 105[Formula: see text]C. The aluminum electrolytic capacitor can be used in tablet PC with long load life.
A MATHEMATICAL MODEL TO STUDY THE IMPACT OF MINING ACTIVITIES AND POLLUTION ON FOREST RESOURCES AND WILDLIFE POPULATION
Authors: JYOTSNA KUMARI , TANDON ABHINAV
Published: April 2017

In this paper, we develop a nonlinear mathematical model that investigates the impact of mining activities and pollution on forest resources and wildlife population. It is assumed that concentration of pollutants grows in the environment at a constant rate and also augments due to different mining activities prevailing in the forest area. The model is formulated in terms of differential equations and analyzed using elements of stability theory and numerical simulation. The obtained results depict that both forest resources as well as wildlife population get very much affected, either directly or indirectly, due to mining activities and environmental pollution. It is being concluded that, in order to save forests, an ecological balance is required to be maintained among forest resources, forest-dependent wildlife population, mining activities and environmental pollution.
MODELING THE INFECTION DYNAMICS OF ONCHOCERCIASIS AND ITS TREATMENT
Authors: OMONDI EVANS OTIENO , NYABADZA FARAI , BONYAH EBENEZER , BADU KINGSLEY
Published: April 2017

Onchocerciasis is one of the neglected tropical diseases caused by Onchocerca volvulus. Ivermectin is known to be effective in the treatment of onchocerciasis because it suppresses the production of microfilariae by the adult female worms for a few months following treatment thus reducing transmission. In this study, a deterministic model is developed to assess the effect of mass treatment of onchocerciasis with ivermectin. The basic reproduction number, [Formula: see text], of the model system is determined and it is observed that the model exhibits backward bifurcation for some parameters implying the existence of multiple endemic equilibria when [Formula: see text]. The existence of multiple equilibria emphasizes the fact that [Formula: see text] is not sufficient to eradicate the disease and the need is to lower [Formula: see text] much below one to make the disease-free equilibrium globally stable. Numerical simulations are done and conclusions drawn with respect to the known treatment protocols in endemic areas. The study results suggest that the mass treatment of the disease with ivermectin should cover a higher proportion of the population to control the disease and eventually eliminate it from the population.
Weak inverses of products — Cline’s formula meets Jacobson lemma
Authors: Mary Xavier
Published: April 2017

We study extensions of Cline’s formula and Jacobson lemma for one-sided, commuting and bicommuting weak inverses, in semigroups and general rings. In particular, we provide various isomorphisms between the (one-sided, commuting and bicommuting) weak inverses of [Formula: see text] and those of [Formula: see text] (or [Formula: see text] and [Formula: see text] when [Formula: see text] and [Formula: see text] satisfy additional identities).
On the non-commuting graph in finite Moufang loops
Authors: Ahmadidelir Karim
Published: April 2017

The non-commuting graph associated to a non-abelian group [Formula: see text], [Formula: see text], is a graph with vertex set [Formula: see text] where distinct non-central elements [Formula: see text] and [Formula: see text] of [Formula: see text] are joined by an edge if and only if [Formula: see text]. The non-commuting graph of a non-abelian finite group has received some attention in existing literature. Recently, many authors have studied the non-commuting graph associated to a non-abelian group. In particular, the authors put forward the following conjectures:

Conjecture 1. Let [Formula: see text] and [Formula: see text] be two non-abelian finite groups such that [Formula: see text]. Then [Formula: see text].

Conjecture 2 (AAM’s Conjecture). Let [Formula: see text] be a finite non-abelian simple group and [Formula: see text] be a group such that [Formula: see text]. Then [Formula: see text].

Some authors have proved the first conjecture for some classes of groups (specially for all finite simple groups and non-abelian nilpotent groups with irregular isomorphic non-commuting graphs) but in [Moghaddamfar, About noncommuting graphs, Sib. Math. J. 47(5) (2006) 911–914], Moghaddamfar has shown that it is not true in general with some counterexamples to this conjecture. On the other hand, Solomon and Woldar proved the second conjecture, in [R. Solomon and A. Woldar, Simple groups are characterized by their non-commuting graph, J. Group Theory 16 (2013) 793–824].

In this paper, we will define the same concept for a finite non-commutative Moufang loop [Formula: see text] and try to characterize some finite non-commutative Moufang loops with their non-commuting graph. Particularly, we obtain examples of finite non-associative Moufang loops and finite associative Moufang loops (groups) of the same order which have isomorphic non-commuting graphs. Also, we will obtain some results related to the non-commuting graph of a finite non-commutative Moufang loop. Finally, we give a conjecture stating that the above result is true for all finite simple Moufang loops.
Linear photoabsorption spectra and vertical excitation energies of microsolvated DNA nucleobases in aqueous solution
Authors: Pola Martina , Kochman Michal A. , Picchiotti Alessandra , Prokhorenko Valentyn I. , Miller R. J. Dwayne , Thorwart Michael
Published: April 2017

Employing density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations in combination with the semiclassical nuclear ensemble method, we have simulated the photoabsorption spectra of the four canonical DNA nucleobases in aqueous solution. In order to model the effects of solvation, for each nucleobase, a number of solvating water molecules were explicitly included in the simulations, and additionally, the bulk solvent was represented by a continuous polarizable medium. We find that the effect of the solvation shell in general is significant, and its inclusion improves the realism of the spectral simulations. The involvement of lone electron pairs in the hydrogen bonding with the solvating water molecules has the effect of systematically increasing the energies of vertical excitation into the [Formula: see text]-type states. Apart from a systematic blue shift of around [Formula: see text][Formula: see text]eV observed in the absorption peaks, the calculated photoabsorption spectra reproduce the measured ones with good accuracy. The photoabsorption spectra are dominated by excited states with [Formula: see text] and partial [Formula: see text] character. No low-energy charge transfer states are observed with the use of the CAM-B3LYP and M06-2X functionals.
Double shuffle and Hoffman’s relations for interpolated multiple zeta values
Authors: Wakabayashi Noriko
Published: April 2017

The polynomials interpolating multiple zeta values and multiple zeta-star values using a parameter [Formula: see text] were introduced by Yamamoto. We call these [Formula: see text]-MZVs. In this paper, we establish the shuffle product for [Formula: see text]-MZVs to prove Hoffman type relation and double shuffle relation for [Formula: see text]-MZVs.
Eventually stable rational functions
Authors: Jones Rafe , Levy Alon
Published: April 2017

For a field [Formula: see text], rational function [Formula: see text] of degree at least two, and [Formula: see text], we study the polynomials in [Formula: see text] whose roots are given by the solutions in [Formula: see text] to [Formula: see text], where [Formula: see text] denotes the [Formula: see text]th iterate of [Formula: see text]. When the number of irreducible factors of these polynomials stabilizes as [Formula: see text] grows, the pair [Formula: see text] is called eventually stable over [Formula: see text]. We conjecture that [Formula: see text] is eventually stable over [Formula: see text] when [Formula: see text] is any global field and [Formula: see text] is any point not periodic under [Formula: see text] (an additional non-isotriviality hypothesis is necessary in the function field case). We prove the conjecture when [Formula: see text] has a discrete valuation for which (1) [Formula: see text] has good reduction and (2) [Formula: see text] acts bijectively on all finite residue extensions. As a corollary, we prove for these maps a conjecture of Sookdeo on the finiteness of [Formula: see text]-integral points in backward orbits. We also give several characterizations of eventual stability in terms of natural finiteness conditions, and survey previous work on the phenomenon.