bluuebunny/crossref_metadata_2025 huggingface dataset:
Enriching STEP Product Model With Geometric Dimension and Tolerance Information for One-Dimensional Tolerance Analysis
Authors: Sarigecili Mehmet I. , Roy Utpal , Rachuri Sudarsan
Published: November 2016

Information exchange and sharing become a necessity for digital factory but they have been more challenging as the industry is computerized more. This is mainly because the capabilities of computerized systems have grown significantly in a very rapid pace in their own information structure, and they require to retrieve various data from different computer systems. ISO 10303–STEP has been developed to provide a neutral format for exchanging product data. However, implementation of STEP has several issues, including the following two: (1) the complete STEP file should be processed even for querying a small set of data, and (2) information required for realizing any functional activity (e.g., any analysis on any part of a product) is not explicitly identified. Hence, in this study, functionality-based conformance classes (FCCs) are developed to organize the current conformance classes (CCs) (which are the classes required to be implemented fully in order to be conformant to any particular STEP standard) for supporting different functional activities. Following the concept of data exchange specification (DEX)/template, several templates that are repeatedly used small information groups are introduced in order to create manageable sets of data constructs. In this study, the FCCs for 1D tolerance analysis are developed by enriching the available STEP information models with GD&T. The use of extended STEP models is illustrated with a case study.
Application of Film Cooling to an Unshrouded High-Pressure Turbine Casing
Authors: Collins Matthew , Chana Kamaljit , Povey Thomas
Published: November 2016

In this paper, we describe the design, modeling, and experimental testing of a film cooling scheme employed on an unshrouded high-pressure (HP) rotor casing. The casing region has high thermal loads at both low and high frequency, with the flow being dominated by the potential field of the rotor and over-tip leakage flows. Increasingly high turbine entry temperatures necessitate internal and film cooling of the casing to ensure satisfactory service life and performance. There are, however, very few published studies presenting computational fluid dynamics (CFD) and experimental data for cooled rotor casings. Experimental testing was performed on a film-cooled rotor casing in the Oxford Turbine Research Facility (OTRF)—a rotating transonic facility of engine scale. Unsteady CFD of an HP rotor blade row with a film-cooled casing was undertaken, uniquely with a domain utilizing a sliding interface in the tip gap. A high density array of thin film heat flux gauges (TFHFGs) was used to obtain time-resolved and time-mean results of adiabatic wall temperature and film cooling effectiveness on the film-cooled rotor casing between −30% and +125% rotor tip axial chord. Results are compared to CFD predictions, and mechanisms for interaction of the coolant with the rotor tip are proposed and discussed. Acoustic effects within casing coolant holes due to the passing of the rotor are demonstrated on a 3D CFD geometry, supporting conclusions drawn in earlier work by the authors on the importance of this effect in a casing film cooling system.
On the Transient Three-Dimensional Tribodynamics of Internal Combustion Engine Top Compression Ring
Authors: Baker C. , Theodossiades S. , Rahmani R. , Rahnejat H. , Fitzsimons B.
Published: November 2016

There are increasing pressures upon the automotive industry to reduce harmful emissions as well as meeting the key objective of enhanced fuel efficiency, while improving or retaining the engine output power. The losses in an internal combustion (IC) engine can be divided into thermal and parasitic as well as due to gas leakage because of untoward compression ring motions. Frictional losses are particularly of concern at low engine speeds, assuming a greater share of the overall losses. Piston–cylinder system accounts for nearly half of all the frictional losses. Loss of sealing functionality of the ring pack can also contribute significantly to power losses as well as exacerbating harmful emissions. The dynamics of compression ring is inexorably linked to its tribological performance, a link which has not been made in many reported analyses. A fundamental understanding of the interplay between the top compression ring three-dimensional elastodynamic behavior, its sealing function and contribution to the overall frictional losses is long overdue. This paper provides a comprehensive integrated transient elastotribodynamic analysis of the compression ring to cylinder liner and its retaining piston groove lands' conjunctions, an approach not hitherto reported in the literature. The methodology presented aims to aid the piston ring design evaluation processes. Realistic engine running conditions are used which constitute international drive cycle testing conditions.
A Robust Industrial Procedure for Measuring Modal Sound Fields in the Development of Radial Compressor Stages
Authors: Limacher Peter , Spinder Carsten , Banica Marius C. , Feld Heinz-Jürgen
Published: November 2016

The turbocharger is a significant noise source in large diesel engines, such as those used in container vessels. Its main noise source is the radial compressor, where improvements in silencers and turbocharger insulation have led to a considerable reduction of compressor inlet noise emission over the past few years. As a result, compressor outlet noise is now becoming increasingly significant for large engines. Recently, an in-house compressor testbed was upgraded by adding an acoustic modal measurement system (MSMS) that allows detailed investigation of modal sound fields inside the piping. This forms part of an updated compressor acoustic qualification procedure. This paper is an in-depth treatise of the characteristics of this modal measurement system. The calculation approach for the modal decomposition and a simplified alternative that assumes axial propagation, as well as relevant considerations, such as spatial resolution, averaging, and the use of multiple reference sensors, are addressed. Various measurement parameters, such as repeatability, measurement time, required temperature stability, pressure scaling, flow noise and their impact on measurement uncertainty were investigated. A successful validation of the modal sound measurement system with a well-known modal sound field at the compressor inlet is also presented. Finally, the characteristics of the modal sound fields of the compressor outlet of a typical modern turbocharger are discussed. Modal decompositions at the first two blade passing frequencies (BPFs) are presented for selected operating points (OPs). The response of total sound power levels (PWLs) to compressor speed along the operating line (OL) is examined by means of both the present and the simplified algorithm. A sensitivity analysis shows the impact of volume flow and rotational speed on the modal sound distribution.
Assessment of Solar Gas Turbine Hybridization Schemes
Authors: Kalathakis C. , Aretakis N. , Roumeliotis I. , Alexiou A. , Mathioudakis K.
Published: November 2016

A simulation environment allowing steady state and transient modeling is used for assessing several gas turbine based cycles proposed for solar hybridization. First, representative open cycle gas turbine configurations, namely, (a) single shaft (SS), (b) recuperated single-shaft, (c) twin shaft (TS), and (d) two-spool three-shaft, intercooled, recuperated, are evaluated. The importance of design point selection in terms of solar share value is highlighted. Solar steam injection gas turbine cycle (STIG) alternatives, namely, solar steam only and solar/fuel gas steam, are then assessed. Finally, the concept of a dual fluid receiver (DFR) for exploiting the rejected solar power by producing steam during sunny hours with high irradiation is demonstrated. The effects of hybridization on performance and operability are established and evaluated. Solarization effect on performance is estimated in terms of annual produced power and fossil fuel savings. The results indicate that the spool arrangement affects the suitability of a gas turbine for hybridization. Recuperated configurations performed better for the design constrains imposed by current technology solar parts. Solar steam injection is a promising solution for retrofitted fuel-only and conventional STIG engines.
Observability Analysis of Relative Localization Filters Subjected to Platform Velocity Constraints
Authors: De Silva Oscar , Mann George K. I. , Gosine Raymond G.
Published: November 2016

This research study performs an observability analysis of the relative localization problem related to multirobotic systems. The study considers different constraints related to the availability of relative position measurements and platform velocity measurements. Constraints related to these measurement sources arise due to several reasons such as, sensing limitations especially in aerial platforms, field of view limitations of sensors, and communication bandwidth limitations that may affect the available measurement rate. Although numerous observability studies are reported for localization of multirobot systems, most of these studies do not investigate the problem under constraints related to platform velocity sensing capabilities, and moreover, these do not investigate the global uniqueness of its results. This paper analyzes observability of the relative localization problem in detail for multiple practical scenarios having limited measurement sources and then extends the study with a global uniqueness analysis of the results. The paper establishes theoretical limitations and design recommendations relevant to relative localization frameworks, which are validated through numerical and experimental evaluations using a multirobot system equipped with relative positioning sensors.
Dynamic Characteristics of a Pressure-Compensated Inlet-Metered Pump
Authors: Wisch Julie K. , Manring Noah D. , Fales Roger C.
Published: November 2016

Pressure-compensated pumps are routinely used for supplying fluid power for hydraulic control systems. These pumps traditionally exhibit significant overshoot and oscillation before reaching a steady-state pressure condition, thus requiring the use of downstream safety valves to prevent over pressurization. In addition to over pressurizing the hydraulic control system, the response of the traditional pressure-compensated pump often induces excessive noise and creates instability for other components within the system. In this paper, a nontraditional pressure-compensated hydraulic pump is studied based upon the paradigm that has been offered by diesel-engine technology. This technology uses an inlet-metered pump to provide pressurized fuel for the high-pressure, fuel-injector rail. The analysis of this paper shows that a system of this type may be used to produce a first-order pressure response with no overshoot and oscillation, and that the characteristic time constant and settling time may be designed by specifying parameters that are identified in this research. The problem of cavitation damage is also discussed based upon preliminary testing done at the University of Missouri, and it is suggested that by using hardened machine parts cavitation damage may be prevented in these machines. In conclusion, this paper shows that continued development of the inlet-metered pump may be warranted for those applications where pressure overshoot and oscillation cannot be tolerated due to safety, noise, or other dynamical considerations.
Torque Converter Capacity Improvement Through Cavitation Control by Design
Authors: Liu Cheng , Wei Wei , Yan Qingdong , Weaver Brian K.
Published: November 2016

Heavy cavitation in torque converters can have a significant effect on hydrodynamic performance, particularly with regards to the torque capacity. The objective of this study is to therefore investigate the effects of pump and turbine blade geometries on cavitation in a torque converter and improve the torque capacity without increasing the torus dimension. A steady-state homogeneous computational fluid dynamics (CFD) model was developed and validated against test data at stall operating condition. A full flow passage with a fixed turbine-stator domain was used to improve the convergence and accuracy of the cavitation model. Cavitation analysis was carried out with various pump and turbine blade geometries. It was found that there is a threshold point for pump blade exit angle in terms of its effect on torque capacity due to heavy cavitation. Further increasing the pump blade exit angle past this point will worsen cavitation condition and decrease torque capacity. The study also shows that a higher turbine blade exit angle, i.e., lower stator incidence angle, could reduce flow separation at the stator suction surface and consequently abate cavitation. A base high-capacity torque converter was upgraded utilizing the cavitation model, and the resulting design exhibited a 20.7% improvement in capacity constant without sacrificing other performance metrics.
Analysis of Contact Pressure of Mechanically Lined Corrosion Resistant Alloy Pipe by Hydraulic Expansion Process
Authors: Guo Tianye , Ozturk Fahrettin , Jarrar Firas , Sheikh-Ahmad Jamal Y.
Published: November 2016

In this present study, an improved theoretical model is developed to analyze the manufacturing process of a mechanically lined corrosion resistant alloy (CRA) pipe by a hydraulic expansion. The formula of the relationship between the applied hydraulic pressure and the resulting residual interfacial pressure between the inner liner and outer pipes for the mechanically lined CRA pipe is obtained. The minimum and maximum critical hydraulic pressures are also investigated and an effective forming pressure ranges is found. A 2D axisymmetric finite-element model is built in abaqus™ to simulate the mechanically lined CRA pipe during the hydraulic expansion manufacturing process. The analytical and simulation results are compared with the experimental results found in the literature, which reveals that the theoretically calculated residual contact pressure and the finite-element computed results are in good accord with the experimental results. Therefore, the models built in this paper can be applied in actual manufacturing process of mechanically lined CRA pipes.
Fatigue Damage Analysis of Double-Lap Bolted Joints Considering the Effects of Hole Cold Expansion and Bolt Clamping Force
Authors: Sun Ying , Voyiadjis George Z. , Hu Weiping , Meng Qingchun , Xu Yuanming
Published: November 2016

Hole cold expansion and bolt clamping force are usually applied to improve the fatigue performance of bolted joints. In order to investigate the effects of hole cold expansion and bolt clamping force and reveal the mechanism of these two factors on the fatigue damage of bolted joint, a continuum damage mechanics (CDM) based approach in conjunction with the finite element method is used. The damage-coupled Voyiadjis plasticity constitutive model is used to represent the material behavior, which is implemented by user material subroutine in abaqus. The elasticity and plasticity damage evolutions of the material are described by the stress-based and plastic-strain-based equations, respectively. The fatigue damage of joint is calculated using abaqus cycle by cycle. The fatigue lives of double-lap bolted joints with and without clamping force at different levels of hole cold expansion are all obtained. The characteristics of fatigue damage corresponding to the different conditions are presented to unfold the influencing mechanism of these two factors. The predicted fatigue lives and crack initiation locations are in good agreement with the experimental results available in the literature. The beneficial effects of hole cold expansion and bolt clamping force on the fatigue behavior of bolted joint are presented in this work.
Parallelized Simulation of a Finite Element Method in Many Integrated Core Architecture
Authors: Tak Moonho , Park Taehyo
Published: November 2016

We investigate a domain decomposition method (DDM) of finite element method (FEM) using Intel's many integrated core (MIC) architecture in order to determine the most effective MIC usage. For this, recently introduced high-scalable parallel method of DDM is first introduced with a detailed procedure. Then, the Intel's Xeon Phi MIC architecture is presented to understand how to apply the parallel algorithm into a multicore architecture. The parallel simulation using the Xeon Phi MIC has an advantage that traditional parallel libraries such as the message passing interface (MPI) and the open multiprocessing (OpenMP) can be used without any additional libraries. We demonstrate the DDM using popular libraries for solving linear algebra such as the linear algebra package (LAPACK) or the basic linear algebra subprograms (BLAS). Moreover, both MPI and OpenMP are used for parallel resolutions of the DDM. Finally, numerical parallel efficiencies are validated by a two-dimensional numerical example.
Measurements of humpback whale song sound levels received by a calf in association with a singer
Authors: Chen Jessica , Pack Adam A. , Au Whitlow W. L. , Stimpert Alison K.
Published: November 2016

Male humpback whales produce loud “songs” on the wintering grounds and some sing while escorting mother–calf pairs, exposing them to near-continuous sounds at close proximity. An Acousonde acoustic and movement recording tag deployed on a calf off Maui, Hawaii captured sounds produced by a singing male escort. Root-mean-square received levels ranged from 126 to 158 dB re 1 μPa. These levels represent rare direct measurements of sound to which a newly born humpback calf may be naturally exposed by a conspecific, and may provide a basis for informed decisions regarding anthropogenic sound levels projected near calves.
Twist-induced guidance in coreless photonic crystal fiber: A helical channel for light
Authors: Beravat Ramin , Wong Gordon K. L. , Frosz Michael H. , Xi Xiao Ming , Russell Philip St.J.
Published: November 2016

Twisting the periodic “space” within a coreless photonic crystal fiber creates gravitation-like forces that trap light.
Direct imaging of isofrequency contours in photonic structures
Authors: Regan Emma C. , Igarashi Yuichi , Zhen Bo , Kaminer Ido , Hsu Chia Wei , Shen Yichen , Joannopoulos John D. , Soljačić Marin
Published: November 2016

Photon scattering from minimal disorder in a photonic crystal slab leads to a striking visualization of its isofrequency contours.
Confirmation of a de novo structure prediction for an atomically precise monolayer-coated silver nanoparticle
Authors: Conn Brian E. , Atnagulov Aydar , Yoon Bokwon , Barnett Robert N. , Landman Uzi , Bigioni Terry P.
Published: November 2016

A predicted structure of an organically capped silver nanocluster is confirmed via x-ray diffraction and ab initio theory.
WHO Multi-Country Survey on Abortion-related Morbidity and Mortality in Health Facilities: study protocol
Authors: Kim Caron R , Tunçalp Özge , Ganatra Bela , Gülmezoglu Ahmet Metin ,   WHO MCS-A Research Group
Published: November 2016

Introduction

According to the WHO, abortion accounts for about 8% (4.7–13.2) of maternal mortality worldwide. In 2010, the WHO Multi-Country Survey (MCS) on Maternal and Newborn Health collected data on over 300 000 women who were admitted in health facilities to receive pregnancy-related care. Abortion data were partially captured by centring on severe maternal outcomes (ie, near-miss or maternal deaths). Building on the experiences of the prior MCS as well as current WHO reproductive health projects, we are undertaking a multi-country survey to better capture the burden and severity of abortion-related complications and management among women presenting to the health facilities.

Methods and analysis

This is a large cross-sectional study with prospective data collection. It will be implemented in health facilities in 30 countries across the WHO regions of Africa, Americas, Eastern Mediterranean, Europe, South East Asia and Western Pacific. Countries and facilities will be identified through a multistage sampling methodology. Data collection will be at both the facility and individual levels, involving review of medical records and exit surveys with eligible women using audio computer-assisted self-interview. All women presenting to the health facilities with signs and symptoms of abortion complications will comprise the study population. Online data entry and management will be performed on a web-based data management system. Analysis will include prevalence of abortion-related complications and descriptive frequencies of procedural/non-procedural management and experience of care.

Ethics and dissemination

Ethical issues of the consent process are addressed. Dissemination plans will involve the participating facilities and communities to further strengthen abortion-related research capacity within the MCS on Abortion (MCS-A) countries. Furthermore, dissemination of results will be an iterative process at both the facility and national level to potentially propagate positive changes to abortion-related policies and practices.
Association between job stress and occupational injuries among Korean firefighters: a nationwide cross-sectional study
Authors: Kim Yeong-Kwang , Ahn Yeon-Soon , Kim KyooSang , Yoon Jin-Ha , Roh Jaehoon
Published: November 2016

Objective

We aimed to assess the nature of association between job stress and occupational injuries among firefighters in Korea.

Design

Cross-sectional study.

Setting

We conducted a nationwide survey using self-reported questionnaires in South Korea.

Participants

A survey was conducted among 30 630 firefighters; 25 616 (83.6%) responded. Our study included firefighters who were 20–59 years old. Individuals with <12 months of current job experience and those with missing data were excluded; ultimately, 14 991 firefighters were analysed.

Results

Among fire suppression personnel, high job demands (OR=1.49, 95% CI 1.25 to 1.77), high interpersonal conflicts (OR=1.18, 95% CI 1.02 to 1.37), a poor organisational system (OR=1.33, 95% CI 1.14 to 1.55), and a negative workplace environment (OR=1.41, 95% CI 1.21 to 1.64) were associated with the occurrence of occupational injury; high job demands (OR=1.22, 95% CI 1.01 to 1.47) were also associated with the frequency of injuries. Among emergency medical services personnel, high job demands (OR=1.26, 95% CI 1.03 to 1.54), high interpersonal conflicts (OR=1.40, 95% CI 1.19 to 1.66), a poor organisational system (OR=1.55, 95% CI 1.30 to 1.85), lack of reward (OR=1.43, 95% CI 1.21 to 1.69) and a negative workplace environment (OR=1.30, 95% CI 1.10 to 1.54) were associated with the occurrence of occupational injury; low job control (OR=1.20, 95% CI 1.04 to 1.38), high interpersonal conflicts (OR=1.18, 95% CI 1.03 to 1.36), lack of reward (OR=1.17, 95% CI 1.02 to 1.35) and a negative workplace climate (OR=1.16, 95% CI 1.01 to 1.34) were also associated with a greater number of injuries. Among officers, high job demands (OR=1.96, 95% CI 1.35 to 2.85) and a negative workplace environment (OR=1.54, 95% CI 1.13 to 2.10) were associated with the occurrence of occupational injuries; however, there was no significant correlation between job stress and the number of injuries.

Conclusions

High job stress among firefighters was associated with both the occurrence of occupational injury, and also with an increased frequency of injuries. Therefore, job stress should be addressed to prevent occupational injuries among firefighters.
Phenotypic and antibiogram pattern ofV. choleraeisolates from a tertiary care hospital in Mumbai during 2004–2013: a retrospective cross-sectional study
Authors: Torane V , Kuyare S , Nataraj G , Mehta P , Dutta S , Sarkar B
Published: November 2016

Objectives

Cholera is a major gastroenteric disease with reports on fluctuation and resistance. Hence, the objective is to determine the trend in seasonality, resistance pattern, prevalent biotypes, serotypes and phage types between 2004 and 2013 amongVibrio choleraeisolates.

Design

A retrospective cross-sectional study.

Settings

A single-centre study was carried out at a tertiary care hospital in a metropolitan city (Mumbai) of a developing country (India).

Methods

Records of stool specimen cultures of patients with suspected cholera from January 2004 to December 2013 were analysed. The organisms were identified as per standard protocol. Antimicrobial susceptibility testing was performed as per Clinical Laboratory Standard Institute. Biotyping, serotyping and phage typing were carried out. From the confirmed cases of cholera, demographic and laboratory details were noted. Descriptive analysis was used and the data were presented in the form of percentages.

Results

Vibrio choleraewas predominant in males and was isolated from 9.41% (439/4664) of stool specimens. Variability was found in terms of the gross appearance of stool specimens, seasonal trend and antibiotic resistance pattern. The antimicrobial susceptibility showed a waxing and waning pattern for most of the antibiotics (ampicillin, cefuroxime, chloramphenicol, tetracycline) tested, while for a few others the strains were either uniformly sensitive (gentamicin, norfloxacin) or resistant (trimethoprim-sulfamethoxazole, nalidixic acid). All isolates belonged to subgroup O1 and biotype El Tor. The most common serotype was Ogawa. The predominant phage type was T2 (old scheme) and T27 (new scheme).

Conclusions

The predominant biotype, serotype and phage type were El Tor, Ogawa and T27 phage, respectively. The changing trends in antimicrobial resistance pattern over the years necessitate continued epidemiological and microbiological surveillance of the disease.
Nailfold capillary morphological characteristics of hand-arm vibration syndrome: a cross-sectional study
Authors: Chen QingSong , Chen GuiPing , Xiao Bin , Lin HanSheng , Qu HongYing , Zhang DanYing , Shi MaoGong , Lang Li , Yang Bei , Yan MaoSheng
Published: November 2016

Objective

The purpose of this study was to investigate the characteristics of nailfold capillaroscopy associated with hand-arm vibration syndrome (HAVS).

Methods

In total, 113 male gold miners were recruited: 35 workers who were chronically exposed to vibration and developed vibration-induced white finger were defined as the HAVS group, 39 workers who were exposed to vibration but did not have HAVS were classified as the vibration-exposed controls (VEC) group, and 39 workers without vibration exposure were categorised as the non-VEC (NVEC) group. Video capillaroscopy was used to capture images of the 2nd, 3rd and 4th fingers of both hands. The following nailfold capillary characteristics were included: number of capillaries/mm, avascular areas, haemorrhages and enlarged capillaries. The experiments were carried out in the same winter. All characteristics were evaluated under blinded conditions.

Results

Significant differences in all morphological characteristics existed between the groups (p<0.05). Avascular areas in the HAVS, VEC and NVEC groups appeared in 74.3%, 43.6% and 25.0% of participants, respectively. A higher percentage of participants had haemorrhages in the HAVS group (65.7%) compared with the other groups (VEC: 7.7% and NVEC: 7.5%). The number of capillaries/mm, input limb width, output limb width, apical width, and ratio of output limb and input limb all had more than 70% sensitivity or specificity of their cut-off value.

Conclusions

Nailfold capillary characteristics, especially the number of capillaries/mm, avascular areas, haemorrhages, output limb width, input limb width and apical width alterations, revealed significant associations with HAVS.
Perceived causes of differential attainment in UK postgraduate medical training: a national qualitative study
Authors: Woolf Katherine , Rich Antonia , Viney Rowena , Needleman Sarah , Griffin Ann
Published: November 2016

Objectives

Explore trainee doctors’ experiences of postgraduate training and perceptions of fairness in relation to ethnicity and country of primary medical qualification.

Design

Qualitative semistructured focus group and interview study.

Setting

Postgraduate training in England (London, Yorkshire and Humber, Kent Surrey and Sussex) and Wales.

Participants

137 participants (96 trainees, 41 trainers) were purposively sampled from a framework comprising: doctors from all stages of training in general practice, medicine, obstetrics and gynaecology, psychiatry, radiology, surgery or foundation, in 4 geographical areas, from white and black and minority ethnic (BME) backgrounds, who qualified in the UK and abroad.

Results

Most trainees described difficult experiences, but BME UK graduates (UKGs) and international medical graduates (IMGs) could face additional difficulties that affected their learning and performance. Relationships with senior doctors were crucial to learning but bias was perceived to make these relationships more problematic for BME UKGs and IMGs. IMGs also had to deal with cultural differences and lack of trust from seniors, often looking to IMG peers for support instead. Workplace-based assessment and recruitment were considered vulnerable to bias whereas examinations were typically considered more rigorous. In a system where success in recruitment and assessments determines where in the country you can get a job, and where work–life balance is often poor, UK BME and international graduates in our sample were more likely to face separation from family and support outside of work, and reported more stress, anxiety or burnout that hindered their learning and performance. A culture in which difficulties are a sign of weakness made seeking support and additional training stigmatising.

Conclusions

BME UKGs and IMGs can face additional difficulties in training which may impede learning and performance. Non-stigmatising interventions should focus on trainee–trainer relationships at work and organisational changes to improve trainees’ ability to seek social support outside work.
Northern Manhattan Hispanic Caregiver Intervention Effectiveness Study: protocol of a pragmatic randomised trial comparing the effectiveness of two established interventions for informal caregivers of persons with dementia
Authors: Luchsinger José A , Burgio Louis , Mittelman Mary , Dunner Ilana , Levine Jed A , Kong Jian , Silver Stephanie , Ramirez Mildred , Teresi Jeanne A
Published: November 2016

Introduction

The prevalence of dementia is increasing without a known cure, resulting in an increasing number of informal caregivers. Caring for a person with dementia results in increased stress and depressive symptoms. There are several behavioural interventions designed to alleviate stress and depressive symptoms in caregivers of persons with dementia with evidence of efficacy. Two of the best-known interventions are the New York University Caregiver Intervention (NYUCI) and the Resources for Enhancing Alzheimer's Caregivers Health (REACH). The effectiveness of the NYUCI and REACH has never been compared. There is also a paucity of data on which interventions are more effective in Hispanics in New York City. Thus, we proposed the Northern Manhattan Hispanic Caregiver intervention Effectiveness Study (NHiCE), a pragmatic clinical trial designed to compare the effectiveness of adaptations of the NYUCI and the REACH in informal Hispanic caregivers of persons with dementia in New York City.

Methods and analysis

NHiCE is a 6-month randomised controlled trial comparing the effectiveness of adaptations of the NYUCI and REACH among 200 Hispanic informal adult caregivers of persons with dementia. The planned number of sessions of the NYUCI and REACH are similar. The primary outcome measures are changes from baseline to 6 months in the Zarit Caregiver Burden Scale and Geriatric Depression Scale. Our primary approach to analyses will be intent-to-treat. The primary analyses will use mixed random effects models, and a full information maximum likelihood approach, with sensitivity analyses using generalised estimating equation.

Ethics and dissemination

NHiCE is approved by the Institutional Review Board of Columbia University Medical Center (protocol AAAM5150). A Data Safety Monitoring Board monitors the progress of the study. Dissemination will include reports of the characteristics of the study participants, as well as a report of the results of the clinical trial.

Trial registration number

NCT02092987, Pre-results.
Age-specific and sex-specific incidence of systemic lupus erythematosus: an estimate from cross-sectional claims data of 2.3 million people in the German statutory health insurance 2002
Authors: Brinks Ralph , Hoyer Annika , Weber Sergej , Fischer-Betz Rebecca , Sander Oliver , Richter Jutta G , Chehab Gamal , Schneider Matthias
Published: November 2016

Objective

To provide an estimate of age-specific incidence rate of physician-diagnosed systemic lupus erythematosus (SLE) for German men and women.

Methods

The age-specific and sex-specific prevalence of diagnosed SLE in claims data is used to estimate the incidence in the German male and female population. The claims data set stems from a representative sample of the statutory health insurance in 2002 and comprises 2.3 million people. The statutory health insurance covers >85% of the German population.

Results

The estimated incidence rates are 0.9 (95% CI 0.7 to 1.1) per 100 000 person-years for men and 1.9 (95% CI 1.7 to 2.2) per 100 000 person-years for women. The age-specific incidence rate of SLE in the male population has a maximum of 2.2 (95% CI 1.0 to 3.4) per 100 000 person-years at the age of 65–70 years. In women, the incidence is peaking at the rate of 3.6 (95% CI 2.9 to 4.3) cases per 100 000 person-years at the age of 20–25 years, but has a second local maximum (2.6, 95% CI 1.5 to 3.8) at menopausal age.

Conclusions

For the first time, representative data on the incidence of SLE in Germany are provided. The estimated incidence rates of SLE for men and women in Germany are at the lower end of other estimates from comparable European countries.
Use of the Pipeline embolization device for recurrent and residual cerebral aneurysms: a safety and efficacy analysis with short-term follow-up
Authors: Kühn Anna Luisa , de Macedo Rodrigues Katyucia , Lozano J Diego , Rex David E , Massari Francesco , Tamura Takamitsu , Howk Mary , Brooks Christopher , L'Heureux Jenna , Gounis Matthew J , Wakhloo Ajay K , Puri Ajit S
Published: November 2016

Objective

Evaluation of the safety and efficacy of the Pipeline embolization device (PED) when used as second-line treatment for recurrent or residual, pretreated ruptured and unruptured intracranial aneurysms (IAs).

Methods

Retrospective review of our database to include all patients who were treated with a PED for recurrent or residual IAs following surgical clipping or coiling. We evaluated neurological outcome and angiograms at discharge, 6- and 12-months’ follow-up and assessed intimal hyperplasia at follow-up.

Results

Twenty-four patients met our inclusion criteria. Most IAs were located in the anterior circulation (n=21). No change of preprocedure modified Rankin Scale score was seen at discharge or at any scheduled follow-up. Complete or near-complete aneurysm occlusion on 6- and 12-month angiograms was seen in 94.4% (17/18 cases) and 93.3% (14/15 cases), respectively. Complete or near-complete occlusion was seen in 100% of previously ruptured and 85.7% (6/7 cases) and 83.3% (5/6 cases) of previously unruptured cases at the 6- and 12-months’ follow-up, respectively. One case of moderate intimal hyperplasia was observed at 6 months and decreased to mild at the 12-months’ follow-up. No difference in device performance was observed among pretreated unruptured or ruptured IAs.

Conclusions

Treatment of recurrent or residual IAs with a PED after previous coiling or clipping is feasible and safe. There is no difference in device performance between ruptured or unruptured IAs.
Acquired megaoesophagus in a Suffolk ram
Authors: Laurence Michael , Curnow Megan , Blignaut Dawie
Published: November 2016

A one‐year‐old Suffolk ram was evaluated after a four‐month history of intermittent left‐sided bloating and regurgitation. The ram had been slowly losing condition while other sheep in the cohort were gaining weight. Severe megaoesophagus was confirmed on lateral thoracic and neck radiographs and a firm, 6‐cm mass at the oesophageal sphincter was palpated during standing exploratory laparotomy. Postmortem examination confirmed an abscess was the cause of the partial oesophageal obstruction. The abscess yielded pure light growth of Streptococcus alactolyticus, an organism not reported to be associated with infection in sheep. Intermittent bloating is an unusual presentation in ruminants, and acquired megaoesophagus has been reported only very occasionally in sheep. This case report expands the list of differential diagnoses for abnormal regurgitation and intermittent bloating, and provides another specific cause of obstructive gastrointestinal disease in sheep. Acquired megaoesophagus was an unusual sequela of this primary disease.
Chronic intermittent hypoxia disturbs insulin secretion and causes pancreatic injury via the MAPK signaling pathway
Authors: Wang Yeying , Hai Bing , Niu Xiaoqun , Ai Li , Cao Yu , Li Ran , Li Yongxia
Published: November 2016

Obstructive sleep apnea (OSA) is a breathing disorder during sleep, with a most prominent character of chronic intermittent hypoxia (CIH), which induces the generation of reactive oxygen species (ROS) that damages multiple tissues and causes metabolic disorders. In this study, we established a rat model of varying OSA with different grades of CIH (12.5% O2, 10% O2, 7.5% O2, and 5% O2) for 12 weeks, and found that CIH stimulated insulin secretion, reduced the insulin:proinsulin ratio in pancreatic tissue, and caused pancreatic tissue lesions and cell apoptosis in a dose-dependent manner. Moreover, CIH promoted the production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, and activated mitogen-activated protein kinase (MAPK) family members, extracellular regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), and P38, depending on the O2concentration. In summary, CIH disturbed insulin secretion, and caused inflammation, lesions, and cell apoptosis in pancreatic tissue via the MAPK signaling pathway, which may be of great significance for clinical treatment of OSA and type 2 diabetes mellitus (T2DM).
The effects of riparian disturbance on the condition and summer diets of age-0 brook trout (Salvelinus fontinalis) in three central Appalachian streams
Authors: Studinski Jered M. , Hafs Andrew W. , Niles Jonathan M. , Hartman Kyle J.
Published: November 2016

Forested headwater streams are dependent on their riparian zones for many critical goods and services. It is assumed that riparian disturbance affects stream food webs, but for some ecologically and economically important taxa like brook trout (Salvelinus fontinalis), little research has been performed. This study found that intense but spatially limited riparian disturbance resulted in significant but context-dependent changes in the diets and condition of age-0 brook trout in three central Appalachian streams. Dietary shifts in two of the streams appeared to enable age-0 brook trout to maintain or increase condition following riparian tree removal. A significant relationship between fish condition and the importance of Ephemeroptera as prey was observed. The lack of dietary shift to energetically important ephemeropterans coincided with decreased fish condition within one stream previously identified to be mildly impacted by acid precipitation. The context within which riparian disturbance occurs plays an important role in determining the overall impact to age-0 brook trout and should be an important consideration in future regulatory and management decisions.
EXPLORING DIVERSIFICATION BENEFITS IN ASIAN EQUITY MARKETS
Authors: MENSAH JONES ODEI , PREMARATNE GAMINI
Published: November 2016

This paper examines the benefits of international diversification from the perspective of local investors in 15 Asian markets whose initial portfolio holdings consist of assets from the respective domestic markets. We employ the step-down approach of the mean–variance spanning test to examine the statistical significance of regional and global diversification benefits. The analysis is conducted using three portfolio groups based on relative strength ranking technique. The empirical evidence suggests greater benefits from regional diversification compared to global diversification, in most instances. For Asian economies with restrictions on international investing, these findings suggest a further liberalization of their markets.
RESOURCE REDISTRIBUTION MECHANISM IN THE CLOSED FRACTAL-CLUSTER RESOURCE MODEL
Authors: VOLOV V. T. , ZUBAREV A. P.
Published: November 2016

The evolutional scenario of the resource distribution in the fractal-cluster system which is identified as the “organism” has been suggested. We propose a model in which the resource redistribution dynamics in the closed system is determined with the ultrametric structure of the system’s space. Moreover, each cluster has its own characteristic time of a transfer to the equilibrium state which is determined with the ultrametric size of the cluster. The general equation which determines this dynamics has been written. For the determined type of the resource transitions among clusters, the solution of this equation has been numerically received. The problem of the parameter identification’s modelling for the real systems has been discussed.
A Survey on Lightweight Authentication Schemes in Vertical Handoff
Authors: Ali Ikram , Faisal Mohammad , Abbas Sohail
Published: November 2016

Lightweight authentication is one of the solutions proposed in order to reduce the time required for authentication during vertical handoff across heterogeneous networks. Reducing the handoff latency is considered to be a challenging issue. It arises when a user requires maintaining its service continuity while traveling across heterogeneous networks. For example, a mobile user may change access networks while being engaged in different scenarios, such as browsing Internet, using real-time applications or collaborating in cooperative information systems. Delay in the vertical handoff creates many problems, i.e. packet loss, service interruption, security problems, etc. Fast and lightweight authentication schemes are always tempted in such application domains because of many benefits, for instance seamless and efficient handoff, service continuity, guaranteed quality of service (QoS) and suitability for real-time applications while maintaining security. Various techniques have been proposed in this domain to reduce authentication delay. However, these methods do not fully address all the issues in the problem domain; for example, these methods have deficiencies in terms of security, monetary cost, signaling cost and packet latency. In this paper, a comparative study of different lightweight authentication methods is presented but the main focus of this work is one of the different implementations. An overview of major problems and their solutions are presented along with their strengths and limitations. Different emerging research areas are also presented in the domain of lightweight authentication in the vertical handoff.
Fuzzy Time Series Customers Prediction: Case Study of an E-Commerce Cash Flow Service Provider
Authors: Hsu Spring C.
Published: November 2016

With lower operational costs, many small and medium-sized enterprises (SMEs) trade via e-commerce, but without the abilities to develop the expensive payment system. Therefore, a cash flow service provider plays critical roles to complete the online transactions. A cash flow service provider must precisely predict those outsourcing customers to serve the customers well under the correctly prepared facilities. Since the adaptive neuro-fuzzy inference systems (ANFIS) have demonstrated prediction efficiency for fuzzy circumstances in many fields, this study attempts to innovate deploying the ANFIS model on the time series predictions for e-commerce cash flow service customers. Moreover, this study takes an e-commerce cash flow service provider in Taiwan for numerical analysis. For the ANFIS predictions, an acceptable prediction error rate of 5.6% is achieved. The results show that fashion industry tops the highest customers share for outsourcing the cash flow services; and the credit cards top the highest share in the payment media choices.
Block Compressed Sensing of Images Using Adaptive Granular Reconstruction
Authors: Li Ran , Liu Hongbing , Zeng Yu , Li Yanling
Published: November 2016

In the framework of block Compressed Sensing (CS), the reconstruction algorithm based on the Smoothed Projected Landweber (SPL) iteration can achieve the better rate-distortion performance with a low computational complexity, especially for using the Principle Components Analysis (PCA) to perform the adaptive hard-thresholding shrinkage. However, during learning the PCA matrix, it affects the reconstruction performance of Landweber iteration to neglect the stationary local structural characteristic of image. To solve the above problem, this paper firstly uses the Granular Computing (GrC) to decompose an image into several granules depending on the structural features of patches. Then, we perform the PCA to learn the sparse representation basis corresponding to each granule. Finally, the hard-thresholding shrinkage is employed to remove the noises in patches. The patches in granule have the stationary local structural characteristic, so that our method can effectively improve the performance of hard-thresholding shrinkage. Experimental results indicate that the reconstructed image by the proposed algorithm has better objective quality when compared with several traditional ones. The edge and texture details in the reconstructed image are better preserved, which guarantees the better visual quality. Besides, our method has still a low computational complexity of reconstruction.
Influence of “J”-Curve Spring Stiffness on Running Speeds of Segmented Legs during High-Speed Locomotion
Authors: Wang Runxiao , Zhao Wentao , Li Shujun , Zhang Shunqi
Published: November 2016

Both the linear leg spring model and the two-segment leg model with constant spring stiffness have been broadly used as template models to investigate bouncing gaits for legged robots with compliant legs. In addition to these two models, the other stiffness leg spring models developed using inspiration from biological characteristic have the potential to improve high-speed running capacity of spring-legged robots. In this paper, we investigate the effects of “J”-curve spring stiffness inspired by biological materials on running speeds of segmented legs during high-speed locomotion. Mathematical formulation of the relationship between the virtual leg force and the virtual leg compression is established. When the SLIP model and the two-segment leg model with constant spring stiffness and with “J”-curve spring stiffness have the same dimensionless reference stiffness, the two-segment leg model with “J”-curve spring stiffness reveals that (1) both the largest tolerated range of running speeds and the tolerated maximum running speed are found and (2) at fast running speed from 25 to 40/92 m s−1both the tolerated range of landing angle and the stability region are the largest. It is suggested that the two-segment leg model with “J”-curve spring stiffness is more advantageous for high-speed running compared with the SLIP model and with constant spring stiffness.