bluuebunny/crossref_metadata_2025 huggingface dataset:
IC6A1A6 vs. IC3A1 Squirrel Cage Induction Generator Cooling Configuration Challenges and Advantages for Wind Turbine Application
Authors: Singh Gopal , Saleh Ahmad , Amos John , Sundaram Kalpathy , Kapat Jayanta
Published: October 2018

Totally enclosed air to air cooled (TEAAC) generator with IC6A1A6 (as per IEC 60034-6) cooling is a widely accepted generator cooling solution for squirrel cage induction generators (SCIG) used in wind power generation, where the generator has two cooling systems, internal and external. The internal cooling is a closed loop system, where a shaft mounted mechanical fan helps in recirculating air inside the generator, and transfers the heat from the generator into an air-to-air heat exchanger. The external cooling system is a separate ventilation system creating airflow from the nacelle through the heat exchanger and removing the heat outside the nacelle with the help of an electrical fan mounted near the non-drive end of the generator. Cooling improvement of generator and bearing windings for performance enhancement is a well known research topic in turbo-generation as well as wind energy. Various winding design effort has been made in past for efficient generator cooling for turbogenerator as well as for wind turbine generator. With the increasing demand of power output, winding and bearing temperature class reaching its limit. Challenge is to come up with a solution for improving the performance of generator in terms of reducing temperature experienced by windings and at the same time reducing the cost. Detailed testing has been done on a test turbine to compare results obtained from open ventilated solution IC3A1 (as per IEC60034-6) and IC6A1A6 cooling for the squirrel cage induction generator. Paper presents advantages in case of using IC3A1 cooling where temperature of windings reduced substantially in comparison with IC6A1A6 cooling. To avoid contamination led windings and bearings hotspots, presented IC3A1 cooling configuration uses a unique design with inlet duct, filters, outlet duct and wire mesh.
Distributed Integrated Solar Combined Cycle Power Plants: Despatchable, Reliable, Affordable, Low Carbon Electricity
Authors: Welch Michael , Anttila Heidi
Published: October 2018

Renewable energy has a significant role to play in helping the world achieve the greenhouse gas emission reduction necessary to achieve the pathway to a 2°C increase in global temperature. Electricity generation from wind and solar resources can contribute immensely to the decarbonization of power generation, but these resources are intermittent. High penetration of intermittent renewable power generation can cause grid stability and control issues for network operators, with fast response fossil fuel power plant necessary to provide security of supply and maintain grid stability. Increasingly natural gas-fueled distributed power generation is being installed to provide the necessary grid support.

However, hybrid power plants comprised of a fossil fuel power generating system, a renewable power generation system and energy storage can provide both the low CO2 electricity required to meet environmental constraints, and the despatchability and stability required by grid operators. Integrated Solar Combined Cycle Power Plants (ISCCs), comprising a Concentrated Solar Power plant and a natural gas fired combined cycle plant, have the potential to simultaneously reduce fossil fuel consumption, provide secure, highly predictable electricity generation, and reduce the cost of integrating renewable energy into a power system.

While a number of ISCCs have been built at a larger scale (above 150MW power output), the concept has rarely been adopted for smaller scale distributed power applications. In addition, the traditional ISCC concept uses a steam bottoming cycle, which consumes water, and often locations where distributed ISCC could be utilized suffer from a scarcity of fresh water.

This paper evaluates whether replacing the steam bottoming cycle with an Organic Rankine Cycle (ORC) alternative can provide a simpler, lower cost distributed ISCC solution that can be utilized on smaller and island grid systems, or mini- and micro-grids, to provide an affordable, water-free, low carbon power generation system.
Cyber-Physical Systems: A New Paradigm for Energy Technology Development
Authors: Tucker D. , Pezzini P. , Bryden K. M.
Published: October 2018

Energy based Cyber-physical systems (CPS) find their greatest popularity in smart grid applications, where a complex computational algorithm imparts “intelligence” to a supervisory control and data acquisition (SCADA) system used for balancing load distributions. In contrast to this static application of CPS technology, research conducted jointly by U.S. Department of Energy’s, National Energy Technology Laboratory (NETL) and Ames Laboratory proposes a new paradigm in which CPS is used as a core technology in energy system development, design, and deployment. The goal is to speed up the development and deployment of advanced concept power plants, reduce the cost and thereby encouraging private and public investment, and substantially reduce the risk of failure. The current technology development paradigm generally starts with models and bench-scale tests, leading to a pilot plant demonstration of the technology before construction of a commercial system. The concept proposed by NETL and Ames incorporates CPS before and during the construction of a pilot plant — arguably the highest risk part of implementing new energy technologies — and then extends the cyber physical infrastructure to the full-scale plant creating a fully functional and coupled digital twin. The creation of a cyber-physical platform as a part of the advanced energy system design and deployment has the potential to enable the “customization” of energy systems to meet local needs and resources. This will reduce cost and environmental impact of energy production and use. Examples of how the technology development process can be changed in the energy sector will be discussed using fuel cell turbine hybrids as an example.
Nodalized Reduced Ordered Model for Stability Analysis of Supercritical Fluid in Heated Channel
Authors: Singh Munendra Pal , Rahman Md. Emadur , Singh Suneet
Published: October 2018

In this paper, a novel nodalized reduced order model (NROM) has been developed to analyze the linear stability in a heated channel using supercritical water (SCW) as a coolant. The presented reduced order model is developed based on the two-phase flow system approach. The model is much simplified, which reduced the requirement of computational efforts and resources. In the heated channel, the SCW’s density shows a dramatic downfall near the pseudo-critical temperature, based on which it has been divided into n number of nodes. The one-dimension partial differentiation conservation equations of energy, mass and momentum are used and have been linearized by a small perturbation applied on its steady-state solution. These PDEs are converted into the corresponding time-dependent, nonlinear ordinary differential equations (ODEs) by using weighted residual method applied under some appropriate assumptions and approximations. These sets of ODEs (n+1 equations) are then solved analytically by using a state space approach to capture the stability boundary (SB) in terms of trans-pseudo-critical phase change number (Ntpc), pseudo-subcooling number (Nspc) by applying a constant external pressure drop (ΔPtpc) condition across the channel. The NROM results are found to be in good agreement with the methodology and have been verified by numerical simulation. To extend this as a nonlinear stability analysis, the different types of the Hopf Bifurcation regime are also reported.
Critical Design Elements for Traveling Wave Thermoacoustic Engines
Authors: McGaughy Mitchell , Boessneck Eric , Salem Thomas , Wagner John
Published: October 2018

Thermoacoustic technology potentially offers a sustainable and reliable solution to help address the continuing demand for electric power. Thermoacoustic devices, operating on the principle of standing or traveling acoustic waves, can be designed as a heat pump or a prime mover system. This technical strategy is environmentally friendly as it utilizes noble gases, or air, as the working fluid and does not directly produce harmful emissions. However, heating and cooling sources are required to create the required thermal gradient. Due to the inherit simplicity and limitation of moving components, thermoacoustic devices require little maintenance and have a forecasted long operational lifespan. This paper will present the design considerations necessary to construct a traveling wave thermoacoustic heat engine. The modeling, analysis, fabrication, and testing with integrated sensors will be discussed to offer insight into the capabilities and subtleties. A case study with system operation at 54 Hz and 7.8% thermal to acoustic efficiency will be presented.
North Carolina Wave Energy Resource: Hydrogen Production Potential
Authors: Raut Gagee , Goudarzi Navid
Published: October 2018

Growing concerns about global warming and depletion of fossil fuel have resulted in exploring alternative energy solutions such as renewable energy resources. Among those, marine and hydrokinetic and in particular wave energy have drawing more interest. Ocean waves are predictable, less variable, and offer higher energy density values. As per National Oceanic and Atmospheric Administration (NOAA), North Carolina ranks 6th with total 484 km coastline length. In this work, six-year National Data Buoy Center (NDBC) wave data from five stations along the North Carolina shore including Wilmington Harbor, Mansonboro Inlet, Oregon Inlet, and Duck FRF (17 and 26 m) are collected. The wave parameters such as wave height and period are analyzed and the potential wave power density values are calculated. The power production from the resource is estimated using wave energy converters. Storing excess energy in the form of hydrogen can be used for a variety of applications. Hence, the cost-performance analysis using the cost per unit method is conducted to obtain the maximum and average hydrogen production from the studied site. The results will be useful to a wide range of development activities in both academia and industry.
Derived Cetane Number As Chemical Potential Indicator for Near-Limit Combustion Behaviors in Gas Turbine Applications
Authors: Won Sang Hee , Carpenter Dalton , Nates Stuart , Dryer Frederick L.
Published: October 2018

The objective of this paper is to elucidate the recently observed strong correlation between derived cetane number (DCN) and lean blow out (LBO) characteristics for both petroleum-derived and alternative jet fuels, as well as their blends. In order to evaluate the variability of fuel physical and chemical properties for petroleum-derived jet fuels, the fuel property database appearing in the DSIC-PQIS 2013 report are rigorously analyzed and compared against fuel-specific data for 17 petroleum-derived and alternative jet fuels and their blends obtained previously in our works. The global combustion characteristics of each fuel for fuel/air mixture were characterized experimentally by determining their combustion property targets (CPTs) — the hydrogen to carbon molar ratio (H/C ratio), the derived cetane number (DCN), the average molecular weight (MW), and surrogate fuel mixtures and threshold sooting index (TSI). Surrogate mixtures of known hydrocarbon species were blended to match the CPTs of target real fuel. The known chemical functional group distributions of the surrogate mixtures for each fuel or fuel blend were then used to predict well-known fundamental combustion behaviors — reflected shock ignition delay times and laminar flame speeds — through quantitative structure-property relationship (QSPR) regression analyses developed from a validation base of single component, binary and ternary mixture database. The results show that the DCN is capable of representing ignition propensity and flame propagating characteristics for both petroleum-derived and alternative jet fuels as well as their mixtures with high fidelity. Finally, the chemical functional group distributions of the real fuels themselves were directly measured using 1H nuclear magnetic resonance (NMR) spectra results. QSPR predictions based upon the experimental NMR functional group measurements are shown to provide a rapid, small sample, characterization tool for predicting the above global combustion behaviors of petroleum derived and alternative jet fuel candidates as well as their blends. Through combustor as well as stirred reactor experiments, fuel DCN has been identified as having major influence on LBO in devices that are sensitive to fuel chemical properties.
Fast Fault Diagnosis of a Lithium-Ion Battery for Hybrid Electric Aircraft
Authors: Hashemi Seyed Reza , Nazari Ashkan , Esmaeeli Roja , Aliniagerdroudbari Haniph , Alhadri Muapper , Zakri Waleed , Mohammed Abdul Haq , Mahajan Ajay , Farhad Siamak
Published: October 2018

A well-designed battery management system along with a set of voltage and current sensors is required to properly measure and control the battery cell operational variables for Hybrid Electric Aircrafts (HEAs). Some critical functions of the battery including State-Of-Charge (SOC) and State-Of-Health (SOH) estimations, over-current, and over-/under-voltage protections are mainly related to current and voltage sensor measurements. Therefore, in case of battery faults occur in HEA, designing a reliable and robust diagnostic procedure is essential. In this study, for Li-ion batteries, a new and fast fault diagnosis technique via collecting data is proposed. Finally, the effectiveness of the proposed diagnostic method is validated, and the results show how overcharge, over-discharge and sensor faults can be accurately detected.
CFD and Control Analysis of a Smart Hybrid Vertical Axis Wind Turbine
Authors: Hosseini Arian , Goudarzi Navid
Published: October 2018

Wind energy has become a dominant source of renewable energy during the past decade. Current hybrid wind turbines are primarily designed and manufactured based on a combination of aerodynamic properties for both Darrieus and Savonius turbines. In this work, the aerodynamic performance characteristics of a smart vertical axis wind turbine (VAWT) with an electro-magnetic switch mechanism for dis-/engagement mechanism is studied analytically and numerically. The proposed novel VAWT offers a high start-up torque by a Savonius turbine and high power coefficient values by a Darrieus turbine. The switch mechanism can further improve the system efficiency by running the turbines together or independently. The proposed hybrid VAWT was modeled as a combined Savonius-type Bach turbine and a 3-bladed H-Darrieus turbine. The hybrid turbine has a self-startup feature and reaches a coefficient of power (Cp) of over 40%. The turbine is also estimated to cover a wide operational range up to TSR 6. The follow on research phases of the project include studying the proposed smart VAWT experimentally and validating the results with those obtained through computational analysis.
Numerical Simulation of Oscillating Multiphase Heat Transfer in Parallel Plates Using Pseudopotential Multiple-Relaxation-Time Lattice Boltzmann Method
Authors: Zhao Wandong , Xu Ben , Zhang Ying
Published: October 2018

Multiphase flows frequently occur in many important engineering and scientific applications, but modeling of such flows is a rather challenging task due to complex interfacial dynamics between different phases, let alone if the flow is oscillating in the porous media. Using humid air as the working fluid in the thermoacoustic refrigerator is one of the research focus to improve the thermoacoustic performance, but the corresponding effect is the condensation of humid air in the thermal stack. Due to the small sized spacing of thermal stack and the need to explore the detailed condensation process in oscillating flow, a mesoscale numerical approach need to be developed. Over the decades, several types of Lattice Boltzmann (LB) models for multiphase flows have been developed under different physical pictures, for example the color-gradient model, the Shan-Chen model, the nonideal pressure tensor model and the HSD model. In the current study, a pseudopotential Multiple-Relaxation-Time (MRT) LBM simulation was utilized to simulate the incompressible oscillating flow and condensation in parallel plates. In the initial stage of condensation, the oscillating flow benefits to accumulate the saturated vapor at the exit regions, and the velocity vector of saturated vapor clearly showed the flow over the droplets. It was also concluded that if the condensate can be removed out from the parallel plates, the oscillating flow and condensation will continuously feed the cold surface to form more water droplets. The effect of wettability to the condensation was discussed, and it turned out that by increasing the wettability, the saturated water vapor was easier to condense on the cold walls, and the distance between each pair of droplets was also strongly affected by the wettability. It’s expected that this study can be used to optimize and redesign the structure of thermal stack in order to produce more condensed water, also this multiphase approach can be extended to more complicated 3D structures.
A Review of Darrieus Water Turbines
Authors: Rehman Wajiha , Rehman Fatima , Malik Muhammad Zain
Published: October 2018

Population explosion and rapid industrialization demands increased power production, whereas, environmental concerns are also an issue. The need of time is to develop eco-friendly technology which exploits renewable energy resources. Water is one of the most promising and cheap renewable energy resource. The gross approximate potential of hydro is 128 PW h per year while technically exploitable potential is only 26 PW h per year. Darrieus water turbine (DWT) is like Darrieus wind turbine but it operates in water instead of air. It is an emerging technology for the low head regions. This article focuses on the performance of DWT under different designing parameters i.e. different blade profiles, pitch angle, azimuth angles, tip speed ratio and effect of ducts. It will also focus on the different numerical models used for its simulation. Finally, based on the study an optimum model is selected for practical operations.
BepiColombo set to probe Mercury's mysteries
Authors: Clery Daniel , Normile Dennis
Published: October 2018

European-Japanese mission will examine idea that innermost planet formed out past Mars.
New science minister's activism sparks debate
Authors: Wade Lizzie
Published: October 2018

Biologist Elena Álvarez-Buylla has spoken out against transgenic maize.
Sky rivers
Authors: Hand Eric
Published: October 2018

Streams of stars falling into our galaxy trace its history and mass. They may even record encounters with clumps of dark matter.
Structural basis of the nucleosome transition during RNA polymerase II passage
Authors: Kujirai Tomoya , Ehara Haruhiko , Fujino Yuka , Shirouzu Mikako , Sekine Shun-ichi , Kurumizaka Hitoshi
Published: October 2018

Nucleosomal DNA transcription

In eukaryotes, the basic chromatin unit nucleosome stalls RNA polymerase II (RNAPII) when it transcribes genetic information on DNA. Using cryo–electron microscopy, Kujirai
et al.
explored seven structures of the RNAPII-nucleosome complex, in which RNAPII pauses at four locations on the nucleosome. These serial snapshots of the RNAPII progression reveal the molecular mechanism of how RNAPII peels the nucleosomal DNA off the histone stepwise.

Science
, this issue p.
595
Cancer origins—genetics rules the day
Authors: Kareta Michael S. , Sage Julien
Published: October 2018

Similar cancers from different source tissues share molecular mechanisms
Activating plasmonic chemistry
Authors: Cortés Emiliano
Published: October 2018

Plasmonic photocatalysts can reduce activation barriers and unlock reaction pathways
Renewable energy for Puerto Rico
Authors: Massol-Deyá Arturo , Stephens Jennie C. , Colón Jorge L.
Published: October 2018

Puerto Rico is not prepared for another hurricane. A year ago, Hurricane María obliterated the island's electric grid, leading to the longest power outage in U.S. history. This disrupted medical care for thousands and contributed to an estimated 2975 deaths. The hurricane caused over $90 billion in damage for an island already in economic crisis. Although authorities claim that power was restored completely, some residents still lack electricity. Despite recovery efforts, the continued vulnerability of the energy infrastructure threatens Puerto Rico's future. But disruptions create possibilities for change. Hurricane María brought an opportunity to move away from a fossil fuel–dominant system and establish instead a decentralized system that generates energy with clean and renewable sources. This is the path that will bring resilience to Puerto Rico.
NanI Sialidase Is an Important Contributor to Clostridium perfringens Type F Strain F4969 Intestinal Colonization in Mice
Authors: Navarro Mauricio A. , Li Jihong , McClane Bruce A. , Morrell Eleonora , Beingesser Juliann , Uzal Francisco A.
Published: October 2018

Clostridium perfringens
type F (formerly enterotoxigenic
C. perfringens
type A) strains produce an enterotoxin (CPE) to cause acute cases of food poisoning and chronic nonfoodborne human gastrointestinal diseases (NFD), e.g., antibiotic-associated diarrhea (AAD). NFD strains also produce NanI sialidase, an extracellular enzyme that releases sialic acids from sialyated host macromolecules.
Salinomycin Inhibits Influenza Virus Infection by Disrupting Endosomal Acidification and Viral Matrix Protein 2 Function
Authors: Jang Yejin , Shin Jin Soo , Yoon Yi-Seul , Go Yun Young , Lee Hye Won , Kwon Oh Seung , Park Sehee , Park Man-Seong , Kim Meehyein
Published: October 2018

Influenza virus is a main cause of viral respiratory infection in humans as well as animals, occasionally with high mortality. Circulation of influenza viruses resistant to the matrix protein 2 (M2) inhibitor, amantadine, is highly prevalent. Moreover, the frequency of detection of viruses resistant to the neuraminidase inhibitors, including oseltamivir phosphate (OSV-P) or zanamivir, is also increasing. These issues highlight the need for discovery of new antiviral agents with different mechanisms. Salinomycin as the monovalent cation-proton antiporter exhibited consistent inhibitory effects against influenza A and B viruses. It plays multifunctional roles by blocking endosomal acidification and by inactivating the proton transport function of M2, the key steps for influenza virus uncoating. Notably, salinomycin resulted in marked therapeutic effects in influenza virus-infected mice when combined with OSV-P, suggesting that its chemical derivatives could be developed as an adjuvant antiviral therapy to treat influenza infections resistant or less sensitive to existing drugs.
Persistent Interactions with Bacterial Symbionts Direct Mature-Host Cell Morphology and Gene Expression in the Squid-Vibrio Symbiosis
Authors: Kremer Natacha , Koch Eric J. , El Filali Adil , Zhou Lawrence , Heath-Heckman Elizabeth A. C. , Ruby Edward G. , McFall-Ngai Margaret J.
Published: October 2018

A long-term relationship between symbiotic partners is often characterized by development and maturation of host structures that harbor the symbiont cells over the host’s lifetime. To understand the mechanisms involved in symbiosis maintenance more fully, we studied the mature bobtail squid, whose light-emitting organ, under experimental conditions, can be transiently or persistently colonized by
Vibrio fischeri
or remain uncolonized. Superficial anatomical changes in the organ were largely independent of symbiosis. However, both the microanatomy of cells with which symbionts interact and the patterns of gene expression in the mature animal were due principally to the persistent interactions of host and symbiont cells rather than to a response to early colonization events. Further, the characteristic pronounced daily rhythm on the host transcriptome required persistent
V. fischeri
colonization of the organ. This experimental study provides a window into how persistent symbiotic colonization influences the form and function of host animal tissues.
Sarcoidosis and HIV infection in a native Saudi man
Authors: Ibrahim Islam A , Estaitieh Osama M , Alrabee Hadeel A , Alzahrani Mazen
Published: October 2018

Sarcoidosis is a rare condition among native Saudis. It typically presents with asymptomatic chest radiographs, exertional breathlessness and cough. The coexistence of sarcoidosis and HIV is also rare, and the overlap of the symptoms makes their differential diagnosis challenging. Nevertheless, the outcome of sarcoidosis is favourable with or without the presence of HIV. We present a case of a 55-year-old native Saudi man with extremely atypical sarcoidosis presentation coexisting with HIV. This case highlights the association between the two pathologies, and the difficulties encountered in establishing a proper diagnosis in the presence of two overlapping diseases.
Cardiac arrest due to critical stenosis of a bicuspid aortic valve mimicking left main coronary artery occlusion on ECG
Authors: Saxena Abhinav , Sabharwal Nitin , Topi Bernard , Crooke Gregory
Published: October 2018

A 49-year-old man presented to the emergency room after a cardiac arrest. On arrival, the patient’s ECG showed ST-segment elevations in the aVR and anteroseptal leads with diffuse ST depression suggestive of left main coronary artery occlusion. Subsequent coronary catheterisation showed normal coronaries but revealed severe stenosis of his bicuspid aortic valve. A surgical replacement of the aortic valve was performed, and the patient recovered successfully.
Hereditary angioedema: a mother diagnosing her child using Google as a diagnostic aid
Authors: Srikantharajah Thanusha , Jakobsen Marianne Antonius , Bygum Anette
Published: October 2018

Hereditary angioedema (HAE), due to C1-inhibitor deficiency, is a rare autosomal dominant and potentially life-threatening disease characterised by recurrent oedema attacks of skin, mucosa and viscera. Due to the rarity and the fact that symptoms of HAE imitate other forms of angioedema and other conditions, HAE may be misdiagnosed, especially in emergency settings. Consequently, patients with HAE may experience significant delays in diagnosis. Without an accurate diagnosis patients with HAE may not receive proper treatment. At times ’Doctor Google' may be an important tool in establishing the diagnosis. The aim of this case report is to emphasise the importance of listening to patients and relatives and being humble to ’Doctor Google'. Furthermore, the aim is to remind all healthcare personal of HAE and the importance of considering the rare differential diagnoses to common symptoms.
Impact of workplace violence and compassionate behaviour in hospitals on stress, sleep quality and subjective health status among Chinese nurses: a cross-sectional survey
Authors: Zhang Shu-E , Liu Wenhui , Wang Jinghui , Shi Yu , Xie Fengzhe , Cang Shuang , Sun Tao , Fan Lihua
Published: October 2018

Objectives

The aim of this study is to describe the current state of workplace violence (WPV) and compassionate behaviour towards nurses and to explain how they affect nurses’ stress, sleep quality and subjective health status.

Design

A cross-sectional online survey study.

Setting

The survey was conducted across eight provinces in China.

Participants

A total of 1024 nurses were recruited to complete an online questionnaire survey from February to May 2016 in China.

Results

Approximately 75.4% participants had experienced some form of violence. Most of the participants experienced WPV such as verbal violence (65.2%), made difficulties (54.5%), tarnished reputation (37.5%), mob behaviour (34.9%), intimidation behaviour (18.8%), physical violence (14.6%) and sexual harassment (5.9%). In this study, 92.4% participants experienced compassionate behaviour from their coworkers (84.9%), supervisors (67.3%), and from their patients (65.3%). The results show that the exposure to WPV behaviour significantly affected the psychological stress (β=0.295, p<0.01), sleep quality (β=−0.198, p<0.01) and subjective health status (β=−0.252, p<0.01) of nurses. The exposure to compassionate behaviour significantly affected the psychological stress (β=−0.229, p<0.01), sleep quality (β=0.326, p<0.01) and subjective health status (β=0.342, p<0.01) of nurses. The results of the mediation analysis showed that psychological stress is a partial mediator in the relationship between violence and sleep quality (β=−0.458, p<0.01) and between violence and subjective health (β=−0.425, p<0.01). Moreover, psychological stress also partially mediated the relationship between compassionate behaviour and sleep quality (β=−0.473, p<0.01), and between compassionate behaviour and subjective health (β=−0.405, p<0.01).

Conclusion

In China, most nurses have experienced different forms of WPV from patients and/or their relatives, as well as experiencing various forms of compassionate behaviour from their coworkers, supervisors and/or patients. This study investigates the prevalence of the different types of WPV and compassionate behaviour. Several aspects of harm to nurses from exposure to violence is confirmed. We found that WPV can damage nurses’ health outcomes, while compassionate behaviours were beneficial to their health outcomes. A harmonious nursing environment should be provided to minimise threats to nurses’ health status.
Ultrasound assessment of diaphragmatic dysfunction as a predictor of weaning outcome from mechanical ventilation: a systematic review and meta-analysis
Authors: Qian Zhicheng , Yang Ming , Li Lin , Chen Yaolong
Published: October 2018

Objective

The aim of this systematic review was to assess the diaphragmatic dysfunction (DD) as a predictor of weaning outcome.

Background

Successful weaning depends on several factors: muscle strength, cardiac, respiratory and metabolic. Acquired weakness in mechanical ventilation is a growing important cause of weaning failure. With the development of ultrasonography, DD can be evaluated with ultrasound in weakness patients to predict weaning outcomes.

Methods

The Cochrane Library, PubMed, Embase, Ovid Medline, WanFang Data and CNKI were systematically searched from the inception to September 2017. Ultrasound assessment of DD in adult mechanical ventilation patients was included. Two independent investigators assessed study quality in accordance with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The primary outcome was diaphragmatic thickness and excursion in the weaning success and failure group. The secondary outcome was the influence of DD on weaning outcome.

Results

Eleven studies involving a total of 436 patients were included. There were eight studies comparing diaphragmatic excursion (DE), five comparing the diaphragmatic thickening fraction (DTF) and two comparing DD between groups with and without successful weaning. Overall, the DE or DTF had a pooled sensitivity of 0.85 (95% CI 0.77 to 0.91) and a pooled specificity of 0.74 (95% CI 0.66 to 0.80) for predicting weaning success. There was high heterogeneity among the included studies (I2=80%; p=0.0006). The rate of weaning failure was significantly increased in patients with DD (OR 8.82; 95% CI 3.51 to 22.13; p<0.00001).

Conclusions

Both DE and DTF showed good diagnostic performance to predict weaning outcomes in spite of limitations included high heterogeneity among the studies. DD was found to be a predictor of weaning failure in critically ill patients.
Research protocol for the exploration of experiences of Aboriginal Australian mothers and healthcare professionals when using the Edinburgh Postnatal Depression Scale: a process-oriented validation study using triangulated participatory mixed methods
Authors: Chan Ai Wen , Skeffington Petra , Reid Corinne , Marriott Rhonda
Published: October 2018

Introduction

Adopting a process-oriented framework for test validation can help to establish whether this tool has the potential to be an acceptable, valid and reliable indicator of depression for mothers and mothers-to-be. This mixed-methods research protocol seeks to explore the views and experiences of Aboriginal mothers and healthcare professionals in relation to the Edinburgh Postnatal Depression Scale (EPDS), and is intended to highlight potential barriers in perinatal mental health conceptualisation, engagement and response style.

Methods and analysis

Thematic analysis will be applied to interview transcripts of Aboriginal Australian mothers (n=6+) and healthcare professionals (n=6+) to identify key themes. The process-focused validation model will use narratives about experiences of using the EPDS as the priority point of analysis. Item-level data and process-level (experience) data are key phenomenological data. The interview-based narratives will be then compared with EPDS scores to check for points of congruence and divergence. This will be done at two time points, antenatally and postnatally, to assess changes in assessment processes and perceptions. Bridging evidence-based research with clinical practice in an Aboriginal Australian context will be facilitated by an investigation of the perceived cultural relevance and likely clinical effectiveness of EPDS. Such evidence is critical to understanding whether the EPDS fulfils its intended purpose. The guiding principles in designing this research protocol is to benefit the well-being of young Aboriginal families and communities through partnership with Aboriginal women.

Ethics and dissemination

Ethics approval was obtained from Human Research Ethics Committee of Murdoch University and from Western Australian Aboriginal Health Ethics Committee (WAAHEC). Participating healthcare sites and services have provided letters of support. Results of this study will be submitted for publication in a peer-reviewed journal.
Twenty-year time trends in hypertension prevalence in Yi people of China: three successive cross-sectional studies, 1996–2015
Authors: Zhang Jia , Wan Shaoping , Zhang Biao , Dong Fen , Pan Li , Yihuo Wuli , Gong Haiying , Yang Fang , Xu Guodong , Li Zheng , Li Guoju , Li Yanlong , Wang Xiaoyang , Shan Guangliang
Published: October 2018

Objective

To explore the trend of hypertension prevalence and related factors in Yi people from 1996 to 2015.

Methods

Three successive cross-sectional surveys were conducted in Liangshan Yi Autonomous Prefecture in 1996, 2007 and 2015, respectively. A total of 8448 participants aged 20–80 years (5040 Yi farmers, 3408 Yi migrants) were included in final analysis.

Results

Overall, the age-standardised prevalence of hypertension in migrants was significantly higher than in farmers. Furthermore, the age-standardised prevalence rates increased from 10.1% to 15.3% to 19.6% in Yi migrants and from 4.0% to 6.3% to 13.1% in Yi farmers during 1996 to 2007 to 2015. The highest 2015-to-1996 ratio of age-standardised hypertension prevalence was in male farmers (ratio=4.30), whereas despite the highest prevalence of hypertension, the equivalent figure in male migrants was 1.57. The older age, overweight and obesity were persistent risk factors of hypertension in three periods. After adjusted for age and body mass index, the difference of hypertension prevalence between 1996 and 2015 then vanished in male migrants (OR=1.335; 95% CI: 0.884 to 2.015) and female farmers (OR=1.267; 95% CI: 0.590 to 2.719). The disparities of hypertension prevalence between Yi migrants and farmers were not statistically significant in all subgroups when adjusted for age, body mass index and education.

Conclusions

Over the past two decades, the hypertension prevalence in Yi people has significantly increased. Yi migrants were more likely to be hypertensive than Yi farmers which was predominantly driven by the discrepancy of body mass index between them.
OPtimising Treatment for MIld Systolic hypertension in the Elderly (OPTiMISE): protocol for a randomised controlled non-inferiority trial
Authors: Sheppard James P , Burt Jenni , Lown Mark , Temple Eleanor , Benson John , Ford Gary A , Heneghan Carl , Hobbs F D Richard , Jowett Sue , Little Paul , Mant Jonathan , Mollison Jill , Nickless Alecia , Ogburn Emma , Payne Rupert , Williams Marney , Yu Ly-Mee , McManus Richard J
Published: October 2018

Introduction

Recent evidence suggests that larger blood pressure reductions and multiple antihypertensive drugs may be harmful in older people, particularly frail individuals with polypharmacy and multimorbidity. However, there is a lack of evidence to support deprescribing of antihypertensives, which limits the practice of medication reduction in routine clinical care. The aim of this trial is to examine whether antihypertensive medication reduction is possible in older patients without significant changes in blood pressure control at follow-up.

Methods and analysis

This trial will use a primary care-based, open-label, randomised controlled trial design. A total of 540 participants will be recruited, aged ≥80 years, with systolic blood pressure <150 mm Hg and receiving ≥2 antihypertensive medications. Participants will have no compelling indication for medication continuation and will be considered to potentially benefit from medication reduction due to existing polypharmacy, comorbidity and frailty. Following a baseline appointment, individuals will be randomised to a strategy of medication reduction (intervention) with optional self-monitoring or usual care (control). Those in the intervention group will have one antihypertensive medication stopped. The primary outcome will be to determine if a reduction in medication can achieve a proportion of participants with clinically safe blood pressure levels at 12-week follow-up (defined as a systolic blood pressure <150 mm Hg), which is non-inferior (within 10%) to that achieved by the usual care group. Qualitative interviews will be used to understand the barriers and facilitators to medication reduction. The study will use economic modelling to predict the long-term effects of any observed changes in blood pressure and quality of life.

Ethics and dissemination

The protocol, informed consent form, participant information sheet and all other participant facing material have been approved by the Research Ethics Committee (South Central—Oxford A; ref 16/SC/0628), Medicines and Healthcare products Regulatory Agency (ref 21584/0371/001–0001), host institution(s) and Health Research Authority. All research outputs will be published in peer-reviewed journals and presented at national and international conferences.

Trial registration number

EudraCT 2016-004236-38;ISRCTN97503221; Pre-results.
Health information technology uses for primary prevention in preventive medicine: a scoping review protocol
Authors: Alturkistani Abrar , Majeed Azeem , Car Josip , Brindley David , Wells Glenn , Meinert Edward
Published: October 2018

Introduction

The use of health information technologies (HITs) has been associated with positive benefits such as improved health outcomes and improved health services. Results from empirical studies reported potential benefits of HITs in preventive medicine measures such as primary prevention. This review will examine the broad range of HITs and their uses and effectiveness in primary prevention.

Methods and analysis

We will conduct searches in relevant databases (MEDLINE, EMBASE, the Cochrane Methodology Register, Cochrane Database of Systematic Reviews, CINAHL, SCOPUS and Web of Science) using Arksey and O’Malley’s scoping review methodology. The scoping review will include all study designs to identify the literature on HIT uses. Two reviewers will independently screen the literature following our screening criteria and using a data abstraction form. Findings will be summarised quantitatively (using numerical counts of HITs) and qualitatively (using narrative synthesis).

Ethics and dissemination

The study will synthesise data from published literature and will not require an ethical approval. The results of the review will be disseminated through a peer-reviewed journal.
Plasma concentrations of second-line antituberculosis drugs in relation to minimum inhibitory concentrations in multidrug-resistant tuberculosis patients in China: a study protocol of a prospective observational cohort study
Authors: Davies Forsman Lina , Niward Katarina , Hu Yi , Zheng Rongrong , Zheng Xubin , Ke Ran , Cai Weiping , Hong Chao , Li Yang , Gao Yazhou , Werngren Jim , Paues Jakob , Kuhlin Johanna , Simonsson Ulrika S H , Eliasson Erik , Alffenaar Jan-Willem , Mansjö Mikael , Hoffner Sven , Xu Biao , Schön Thomas , Bruchfeld Judith
Published: October 2018

Introduction

Individualised treatment through therapeutic drug monitoring (TDM) may improve tuberculosis (TB) treatment outcomes but is not routinely implemented. Prospective clinical studies of drug exposure and minimum inhibitory concentrations (MICs) in multidrug-resistant TB (MDR-TB) are scarce. This translational study aims to characterise the area under the concentration–time curve of individual MDR-TB drugs, divided by the MIC forMycobacterium tuberculosisisolates, to explore associations with markers of treatment progress and to develop useful strategies for clinical implementation of TDM in MDR-TB.

Methods and analysis

Adult patients with pulmonary MDR-TB treated in Xiamen, China, are included. Plasma samples for measure of drug exposure are obtained at 0, 1, 2, 4, 6, 8 and 10 hours after drug intake at week 2 and at 0, 4 and 6 hours during weeks 4 and 8. Sputum samples for evaluating time to culture positivity and MIC determination are collected at days 0, 2 and 7 and at weeks 2, 4, 8 and 12 after treatment initiation. Disease severity are assessed with a clinical scoring tool (TBscore II) and quality of life evaluated using EQ-5D-5L. Drug concentrations of pyrazinamide, ethambutol, levofloxacin, moxifloxacin, cycloserine, prothionamide and para-aminosalicylate are measured by liquid chromatography tandem-mass spectrometry and the levels of amikacin measured by immunoassay. Dried blood spot on filter paper, to facilitate blood sampling for analysis of drug concentrations, is also evaluated. The MICs of the drugs listed above are determined using custom-made broth microdilution plates and MYCOTB plates with Middlebrook 7H9 media. MIC determination of pyrazinamide is performed in BACTEC MGIT 960.

Ethics and dissemination

This study has been approved by the ethical review boards of Karolinska Institutet, Sweden and Fudan University, China. Informed written consent is given by participants. The study results will be submitted to a peer-reviewed journal.

Trial registration number

NCT02816931; Pre-results.
Financial Incentives to Increase Uptake of Pediatric HIV Testing (FIT): study protocol for a randomised controlled trial in Kenya
Authors: Wagner Anjuli D , Njuguna Irene N , Neary Jillian , Omondi Vincent O , Otieno Verlinda A , Babigumira Joseph , Maleche-Obimbo Elizabeth , Wamalwa Dalton C , John-Stewart Grace C , Slyker Jennifer A
Published: October 2018

Introduction

Index case testing (ICT) to identify HIV-infected children is efficient but has suboptimal uptake. Financial incentives (FI) have overcome financial barriers in other populations by offsetting direct and indirect costs. A pilot study found FI to be feasible for motivating paediatric ICT among HIV-infected female caregivers. This randomised trial will determine the effectiveness of FI to increase uptake of paediatric ICT.

Methods and analysis

The Financial Incentives to Increase Uptake of Pediatric HIV Testing trial is a five-arm, unblinded, randomised controlled trial that determines whether FI increases timely uptake of paediatric ICT. The trial will be conducted in multiple public health facilities in western Kenya. Each HIV-infected adult enrolled in HIV care will be screened for eligibility: primary caregiver to one or more children of unknown HIV status aged 0–12 years. Eligible caregivers will be individually randomised at the time of recruitment in equal 1:1:1:1:1 allocation to one of five arms (US$0 (control), US$1.25, US$2.50, US$5.00 and US$10.00). The trial aims to randomise 800 caregivers. Incentives will be disbursed at the time of child HIV testing using mobile money transfer or cash. Arms will be compared in terms of the proportion of adults who complete testing for at least one child within 2 months of randomisation and time to testing. A cost-effectiveness analysis of FI for paediatric ICT will also be conducted.

Ethics and dissemination

This study was reviewed and approved by the University of Washington Institutional Review Board and the Kenyatta National Hospital Ethics and Research Committee. Trial results will be disseminated to healthcare workers at study sites, regional and national policymakers, and with patient populations at study sites (regardless of enrolment in the trial). Randomised trials of caregiver-child FI interventions pose unique study design, ethical and operational challenges, detailed here as a resource for future investigations.

Trial registration number

NCT03049917; Pre-results.
Association between socioeconomic status and risk of hospitalization due to child maltreatment in the USA
Authors: Imran Sehyr , Cross Chad , Das Samrat U
Published: October 2018

Child maltreatment remains a significant problem in the USA. There is a dearth of literature examining the association of socioeconomic status (SES) and incidence of child maltreatment among hospitalized children across the entire USA. Our aim was to study the association between SES and incidence and mortality from child maltreatment among hospitalized children in the USA. We used 2013–2014 data from the Nationwide Inpatient Sample, a discharge database representative of all hospitals in the USA. International Classification of Diseases-9 codes for general child maltreatment were used to identify patients discharged with a primary diagnosis of child maltreatment. Trends in the incidence and outcomes of child maltreatment were compared with SES based on quartiles (Qx) of median household income. In 2013–2014, there were a total of about 2.3 million pediatric discharges. Out of these, a total of 8985 had a primary diagnosis of child maltreatment. Approximately 40 per cent of the cases were from families with the lowest SES (Q1). In-hospital mortality was 2.4 per cent in Q1 (lowest SES) compared with 0.4 per cent in Q4 (highest SES). We conclude that children from lower SES households have a higher incidence of child maltreatment and have worse outcomes, including significantly higher in-hospital mortality among hospitalized children. This trend was generally consistent across all age groups and ethnicities. To our knowledge, this is the first report studying the association between SES and children with child maltreatment among hospitalized children across the entire USA.