bluuebunny/crossref_metadata_2025 huggingface dataset:
Hemodialysis Disparities in African Americans: The Deeply Integrated Concept of Race in the Social Fabric of Our Society
Authors: Norris Keith C. , Williams Sandra F. , Rhee Connie M. , Nicholas Susanne B. , Kovesdy Csaba P. , Kalantar‐Zadeh Kamyar , Ebony Boulware L.
Published: March 2017

End‐stage renal disease (ESRD) is one of the starkest examples of racial/ethnic disparities in health. Racial/ethnic minorities are 1.5 to nearly 4 times more likely than their non‐Hispanic White counterparts to require renal replacement therapy (RRT), with African Americans suffering from the highest rates of ESRD. Despite improvements over the last 25 years, substantial racial differences are persistent in dialysis quality measures such as RRT modality options, dialysis adequacy, anemia, mineral and bone disease, vascular access, and pre‐ESRD care. This report will outline the current status of racial disparities in key ESRD quality measures and explore the impact of race. While the term race represents a social construct, its association with health is more complex. Multiple individual and community level social determinants of health are defined by the social positioning of race in the U.S., while biologic differences may reflect distinct epigenetic changes and linkages to ancestral geographic origins. Together, these factors conspire to influence dialysis outcomes among African Americans with ESRD.
Measurement of plasma cell‐free DNA concentrations in dogs with sepsis, trauma, and neoplasia
Authors: Letendre Jo‐Annie , Goggs Robert
Published: March 2017

Objectives

To determine if cell‐free DNA (cfDNA) was identifiable in canine plasma, to evaluate 3 techniques for the measurement of plasma cfDNA concentrations in dogs presented to an emergency service, and to compare the plasma cfDNA concentrations of healthy dogs to those with sepsis, trauma, and neoplasia.

Design

Retrospective study of banked canine plasma samples collected between May 2014 and December 2014.

Setting

Dogs presented to the emergency service of a university veterinary teaching hospital.

Animals

Plasma cfDNA was measured on residual plasma samples obtained from 15 dogs with sepsis, 15 dogs with moderate‐severe trauma, 15 dogs diagnosed with a sarcoma. Plasma cfDNA was also measured in 15 healthy dogs.

Interventions

None.

Measurements and Main Results

Assay linearity, repeatability, and reproducibility were evaluated. Quantification of cfDNA was performed in duplicate on diluted citrated plasma and following DNA purification using 2 fluorescence assays (SYBR‐Gold; Quant‐iT) and by ultraviolet absorbance spectroscopy. Fluorescence intensities (FIs) were converted to cfDNA concentrations using standard curves. Median FI values and cfDNA concentrations were compared to healthy controls using the Kruskal–Wallis test, with adjustment for multiple comparisons. Alpha was set at 0.05. Both assays had excellent linearity, and acceptable repeatability and reproducibility. Compared to controls, plasma cfDNA concentrations were significantly increased in dogs with sepsis or moderate‐severe trauma with both assays (P ≤ 0.003). Dogs with neoplasia had significantly increased cfDNA concentrations with the Quant‐iT assay only (P = 0.003). When measurements were performed on purified DNA, only dogs with moderate‐severe trauma had significantly increased cfDNA concentrations (P < 0.001; SYBR‐Gold assay).

Conclusions

cfDNA can be readily identified in canine plasma using 2 fluorescence assays. DNA extraction offers no advantage over direct measurement. Compared to healthy controls, dogs with sepsis or moderate‐severe trauma have significantly increased plasma cfDNA concentrations.
Implementation of Evidence‐Based Practice From a Learning Perspective
Authors: Nilsen Per , Neher Margit , Ellström Per‐Erik , Gardner Benjamin
Published: March 2017

Introduction

For many nurses and other health care practitioners, implementing evidence‐based practice (EBP) presents two interlinked challenges: acquisition of EBP skills and adoption of evidence‐based interventions and abandonment of ingrained non‐evidence‐based practices.

Aims

The purpose of this study to describe two modes of learning and use these as lenses for analyzing the challenges of implementing EBP in health care.

Methods

The article is theoretical, drawing on learning and habit theory.

Results

Adaptive learning involves a gradual shift from slower, deliberate behaviors to faster, smoother, and more efficient behaviors. Developmental learning is conceptualized as a process in the “opposite” direction, whereby more or less automatically enacted behaviors become deliberate and conscious.

Conclusion

Achieving a more EBP depends on both adaptive and developmental learning, which involves both forming EBP‐conducive habits and breaking clinical practice habits that do not contribute to realizing the goals of EBP.

Linking Evidence to Action

From a learning perspective, EBP will be best supported by means of adaptive learning that yields a habitual practice of EBP such that it becomes natural and instinctive to instigate EBP in appropriate contexts by means of seeking out, critiquing, and integrating research into everyday clinical practice as well as learning new interventions best supported by empirical evidence. However, the context must also support developmental learning that facilitates disruption of existing habits to ascertain that the execution of the EBP process or the use of evidence‐based interventions in routine practice is carefully and consciously considered to arrive at the most appropriate response.
Mentorship Needs of the Teachers Working in Rural Regions Throughout the Early Years of Their Profession
Authors: Kartal Seçil Eda , Ozdemir Tuncay Yavuz , Yirci Ramazan
Published: March 2017

The purpose of this study is to identify the problems that teachers working in rural regions encounter concerning the Turkish educational system during the years they lack knowledge and experience and to determine their needs for mentorship services. The content analysis method, one of the qualitative research methods, was used in the study. An interview form was prepared by the researchers in accordance with the aims of the study and expert opinions were gathered to check content and face validity. The interview form took its final form according to the opinions of the experts. With respect to the study, 11 teachers working in rural regions were contacted through the purposeful sampling method and their opinions were collected. Interview forms were coded as “G1, G2, G3, …, G11” and transcribed to the computer. The data were analyzed through the content analysis processes. According to the findings of the study; teachers working in rural regions encounter serious problems in time management during the early years of their profession and that the effectiveness of presenting teaching contents decrease due to lack of family participation, low level of student academic achievement, poor physical conditions of the school and insufficient amount of teaching materials. It was also observed that they had problems in administrative operations and official correspondence. Arranging effective in-service training activities and offering mentorship services for inexperienced teachers in rural regions during their early years through a counselor or a mentor who will guide them is crucial in resolving these problems. For the effectiveness of the educational system, it is crucial for teachers, who are working in rural regions during their early years, to benefit from mentorship services in practicing the theoretical knowledge they acquired from their bachelor’s degree.
Connectomics of synaptic microcircuits: lessons from the outer retina
Authors: Rogerson Luke Edward , Behrens Christian , Euler Thomas , Berens Philipp , Schubert Timm
Published: March 2017

Photoreceptors form a sophisticated synaptic complex with bipolar and horizontal cells, transmitting the signals generated by the phototransduction cascade to downstream retinal circuitry. The cone photoreceptor synapse shows several characteristic anatomical connectivity motifs that shape signal transfer: typically, ON‐cone bipolar cells receive photoreceptor input through invaginating synapses; OFF‐cone bipolar cells form basal synapses with photoreceptors. Both ON‐ and OFF‐cone bipolar cells are believed to sample from all cone photoreceptors within their dendritic span. Electron microscopy and immunolabelling studies have established the robustness of these motifs, but have been limited by trade‐offs in sample size and spatial resolution, respectively, constraining precise quantitative investigation to a few individual cells. 3D‐serial electron microscopy overcomes these limitations and has permitted complete sets of neurons to be reconstructed over a comparatively large section of retinal tissue. Although the published mouse dataset lacks labels for synaptic structures, the characteristic anatomical motifs at the photoreceptor synapse can be exploited to identify putative synaptic contacts, which has enabled the development of a quantitative description of outer retinal connectivity. This revealed unexpected exceptions to classical motifs, including substantial interaction between rod and cone pathways at the photoreceptor synapse, sparse photoreceptor sampling and atypical contacts. Here, we summarize what was learned from this study in a more general context: we consider both the implications and limitations of the study and identify promising avenues for future research.

image
Experimentally Measured Effects of Incidence Angle on the Adiabatic and Overall Effectiveness of a Fully Cooled Turbine Airfoil With Shaped Showerhead Holes
Authors: Chavez Kyle , Slavens Thomas N. , Bogard David
Published: March 2017

Manufacturing and assembly variation can lead to shifts in the inlet flow incidence angles of a rotating turbine airfoil row. Understanding the sensitivity of the adiabatic film cooling effectiveness to a range of inlet conditions is necessary to verify the robustness of a cooling design. In order to investigate the effects of inlet flow incidence angles, adiabatic and overall effectiveness data were measured in a low speed linear cascade at 0 deg and 10 deg of the designed operating condition. Tests were completed at an inlet Reynolds number of Re = 120,000 and a turbulence intensity of Tu = 5% at the leading edge of the test article. Particle image velocimetry was used to verify the incident flow angle for each angle studied. The test section was first adjusted so that the pressure distribution and stagnation line of the airfoil matched those predicted by an aerodynamic computational fluid dynamics (CFD) model. IR thermography was then used to measure the adiabatic effectiveness levels of the fully cooled airfoil model with nine rows of shaped holes of varying construction and feed delivery. Measurements were taken over a range of blowing ratios and at a density ratio of DR = 1.23. This process was repeated for the two incidence angles measured, while the inlet pressure to the airfoil model was held constant for these incidence angle changes. Differences in laterally adiabatic effectiveness across the airfoil model were most evident in the showerhead, with changes as large as 0.2. The effect persisted most strongly at s/D = ±35 downstream of the stagnation row of holes, but was visible over the whole viewable area of 160 s/D. The effect was due to the stagnation line affecting the film at the showerhead row. Due to this effect, the showerhead was investigated in detail, including the effects of the stagnation line shift as well as the influence of the incidence angle on the overall effectiveness of the showerhead region. It was found that the stagnation line has the tendency to dramatically increase the near-hole adiabatic effectiveness levels when positioned within the breakout footprint of the hole. The effect persisted for the overall effectiveness study, since the hole spacing for this particular configuration was wide enough that the through hole convection was not completely dominant. This is the first study to present measured effectiveness values over both the pressure- and suction-side surfaces of a fully cooled airfoil for appreciably off-nominal incidence angles as well as examine adiabatic and overall effectiveness levels for a conical stagnation row of holes.
Attenuating the ear canal feedback pressure of a laser-driven hearing aid
Authors: Khaleghi Morteza , Puria Sunil
Published: March 2017

Microphone placement behind the pinna, which minimizes feedback but also reduces perception of the high-frequency pinna cues needed for sound localization, is one reason why hearing-aid users often complain of poor sound quality and difficulty understanding speech in noisy situations. In this paper, two strategies are investigated for minimizing the feedback pressure (thereby increasing the maximum stable gain, MSG) of a wide-bandwidth light-activated contact hearing aid (CHA) to facilitate microphone placement in the ear canal (EC): (1) changing the location of the drive force and its direction at the umbo, and (2) placing an acoustic damper within the EC to reduce the feedback pressure at the microphone location. The MSG and equivalent pressure output (EPO) are calculated in a 3D finite element model of a human middle ear based on micro computed tomography (micro-CT) images. The model calculations indicate that changing the umbo-force direction can decrease feedback pressure, but at the expense of decreased EPO. However the model shows improvements in MSG without sacrificing EPO when an acoustic damper is placed in the EC. This was verified through benchtop experimentation and in human cadaver temporal bones. The results pave the path towards a wide-bandwidth hearing aid that incorporates an EC-microphone design.
Dynamics of cortical dendritic membrane potential and spikes in freely behaving rats
Authors: Moore Jason J. , Ravassard Pascal M. , Ho David , Acharya Lavanya , Kees Ashley L. , Vuong Cliff , Mehta Mayank R.
Published: March 2017

Dendrites are more active than expected

Dendrites occupy more than 90% of neuronal tissue. However, it has not been possible to measure distal dendritic membrane potential and spiking in vivo over a long period of time. Moore
et al.
developed a technique to record the subthreshold membrane potential and spikes from neocortical distal dendrites in freely behaving animals. These recordings were very stable, providing data from a single dendrite for up to 4 days. Unexpectedly, distal dendrites generated action potentials whose firing rate was nearly five times greater than at the cell body.

Science
, this issue p.
eaaj1497
Complete Genome Sequence of
Spiroplasma
sp. NBRC 100390
Authors: Haryono Mindia , Lo Wen-Sui , Gasparich Gail E. , Kuo Chih-Horng
Published: March 2017

Spiroplasma
sp. NBRC 100390 was initially described as a duplicate of
S. atrichopogonis
GNAT3597
T
(=ATCC BAA-520
T
) but later found to be different in the 16S rDNA sequences. Here, we report the complete genome sequence of this bacterium to establish its identity and to facilitate future investigation.
Genome Sequence of Porphyromonas gingivalis Strain A7A1-28
Authors: Xie Gary , Chastain-Gross Ryan P. , Bélanger Myriam , Kumar Dibyendu , Whitlock Joan A. , Liu Li , Farmerie William G. , Zeng Collin L. , Daligault Hajnalka E. , Han Cliff S. , Brettin Thomas S. , Progulske-Fox Ann
Published: March 2017

Porphyromonas gingivalis
is an oral opportunistic pathogen. Sequenced
P. gingivalis
laboratory strains display limited diversity in antigens that modulate host responses. Here, we present the genome sequence of A7A1-28, a strain possessing atypical fimbrillin and capsule types, with a single contig of 2,249,024 bp and a G+C content of 48.58%.
Draft Genome Sequences of Candida glabrata Isolates 1A, 1B, 2A, 2B, 3A, and 3B
Authors: Håvelsrud Othilde Elise , Gaustad Peter
Published: March 2017

Here, we report the draft genome sequences of six
Candida glabrata
isolates. The isolates were taken from blood samples from patients after recurrent
C. glabrata
infection. Two isolates were taken from each of three patients a minimum 3 months apart.
Complete Genome Sequences of
Bacillus
Phages DirtyBetty and Kida
Authors: Flounlacker Kelly , Miller Rachel , Marquez Diana , Johnson Allison
Published: March 2017

We report here the genome sequences of two bacteriophages of the
Bacillus cereus
group, DirtyBetty and Kida. These bacteriophages are double-stranded DNA-containing
Myoviridae
isolated from soil samples using
Bacillus thuringiensis
subsp.
kurstaki
as their host bacteria.
Complete Genome Sequence of Human Adenovirus Type 55 Associated with Acute Respiratory Disease, Isolated from a Military Base in the Republic of Korea
Authors: Gu Se Hun , Song Dong Hyun , Lee Daesang , Huh Kyungmin , Yoo Hongseok , Oh Hong Sang , Jung Jaehun , Woo Koung In , Kim Mirang , Seog Woong , Hwang Il-Ung , Jeong Seong Tae
Published: March 2017

Human adenovirus (HAdV) (genus
Mastadenovirus
; family
Adenoviridae
) serotype 55 is a reemerging pathogen associated with acute respiratory disease. Here, we report the complete genome sequence of HAdV-55 strain AFMC 16-0011, isolated from a military recruit, using next-generation sequencing technology.
Complete Genome Sequence of a Foot-and-Mouth Disease Virus of Serotype O, Isolated from Gochang, Republic of Korea, in 2016
Authors: Kim Taeseong , Ryoo Soyoon , Nah Jin Ju , Sagong Min Geun , Lee Sumee , Lee Kwang-Nyeong , Ko Young-Joon , Park Jong-Hyeon , Lee Myoung-Heon , Wee Sung-Hwan , Tark Dongseob , Ku Bok Kyung
Published: March 2017

The complete genome sequence of a foot-and-mouth disease (FMD) serotype O virus isolated from Gochang, Republic of Korea, is reported here.
Draft Genome Sequence of a Polydroxyalkanoate-Synthesizing Bacterium,
Bacillus
sp. Strain PJC48, Isolated from Activated Sludge
Authors: Gu Jin-Jin , Zhou Ying , Lu Jian-Jiang , Ye Bang-Ce
Published: March 2017

The genome sequence of a
Bacillus
strain is capable of synthesizing polyhydroxyalkanoates, and
Bacillus
sp. is considered a platform strain for the production of many biodegradable materials. Here, we present the sequence of the PJC48 strain genome, which is composed of three chromatin structures, an extracellular structure, and a cytoskeleton.
Complete Genome Sequence of
Enterobacter
sp. Strain ODB01, a Bacterium That Degrades Crude Oil
Authors: Lan Hui , Yang Hui , Li Peiwang , Wang Chong , Zhou Haiyan , Zhou Hui , Pan Hu , Yu Ye , Lu Xiangyang , Tian Yun
Published: March 2017

Enterobacter
sp. strain ODB01, which was isolated from the Changqing oil field, can degrade crude oil efficiently and use crude oil as its sole source of carbon and energy. We report the complete genome sequence of ODB01. The results promote its application in the remediation of petroleum contaminants.
Seroprevalence of Zika Virus in Wild African Green Monkeys and Baboons
Authors: Buechler Connor R. , Bailey Adam L. , Weiler Andrea M. , Barry Gabrielle L. , Breitbach Meghan E. , Stewart Laurel M. , Jasinska Anna J. , Freimer Nelson B. , Apetrei Cristian , Phillips-Conroy Jane E. , Jolly Clifford J. , Rogers Jeffrey , Friedrich Thomas C. , O’Connor David H.
Published: March 2017

Zika virus (ZIKV) is a mosquito-borne virus originally discovered in a captive monkey living in the Zika Forest of Uganda, Africa, in 1947. Recently, an outbreak in South America has shown that ZIKV infection can cause myriad health effects, including birth defects in the children of women infected during pregnancy. Here, we sought to investigate ZIKV infection in wild African primates to better understand its emergence and spread, looking for evidence of active or prior infection. Our results suggest that up to 16% of some populations of nonhuman primate were, at some point, exposed to ZIKV. We anticipate that this study will be useful for future studies that examine the spread of infections from wild animals to humans in general and those studying ZIKV in primates in particular.
Healthcare-seeking behaviour, barriers and mental health of non-domestic migrant workers in Singapore
Authors: Ang Jia Wei , Chia Colin , Koh Calvin J , Chua Brandon W B , Narayanaswamy Shyamala , Wijaya Limin , Chan Lai Gwen , Goh Wei Leong , Vasoo Shawn
Published: March 2017

Background

Low-wage migrant workers are vulnerable to healthcare inequities. We sought to identify potential barriers to healthcare and risk factors for mental health issues in non-domestic migrant workers in Singapore, and identify high-risk subgroups.

Methods

A cross-sectional, interviewer-administered survey of 433 non-domestic migrant workers was conducted at subsidised clinics and a foreign worker dormitory from July to August 2016. Questions assessed healthcare usage patterns, affordability issues, barriers to care and psychological distress using a validated screening scale (Kessler-6).

Findings

Bangladeshi workers surveyed were more likely to be single, have more financial dependents, a lower level of education and salary and pay higher agent fees (p<0.01). 61.4% of workers reported that they had insurance, but had poor understanding of whether it covered inpatient/outpatient expenses. The majority of workers had not, or were not sure if they had, received information about company-bought insurance (72.4%). Among those who had, most reported that information was not in their native language (67.7%). Non-specific psychological distress was found in 21.9%, as estimated by the Kessler-6 scale. Multivariate analysis found that psychological distress was independently associated with Bangladeshi nationals (OR 2.98, 95% CI 1.58 to 5.62; p=0.001) and previous experience of financial barriers to healthcare (OR 3.86, 95% CI 2.25 to 6.62; p<0.0001).

Interpretation

We identified gaps in non-domestic migrant workers' knowledge of healthcare coverage, and substantial financial barriers to healthcare. The Bangladeshi population in our study was at higher risk of such barriers and psychological distress. These represent areas for further research and intervention.
Disposable versus non-disposable tonometer prisms: a UK national survey
Authors: Jasani Kirti M , Putri Christine , Pearl Amy , Sattar Nayeem , Mercieca Karl , Spaeth George , Bhan-Bhargava Archana
Published: March 2017

Purpose

To determine the prevalence of disposable tonometer versus non-disposable tonometer use in the UK and to determine methods of decontamination and frequency of replacement of prisms.

A total of 137 ophthalmology departments were interviewed by telephone using a structured questionnaire. The main outcome measured were:

types of tonometer prisms used in clinic (disposable, non-disposable and/or other)

average disposable prisms used per clinic session

average lifespan of non-disposable prisms

prism preference by glaucoma and other teams within department.

A cost and benefit analysis was then performed on the data acquired.

Results

One hundred and fifty-five departments were identified for the survey. Of these, 137 (88.3%) responded. Eighty-one departments (59.1%) used Tonosafe prisms alone, whereas 22 departments (16.1%) used Goldmann non-disposable prisms exclusively. Thirty-five departments (64%) on average have a change rate of 26.5% per year (range: 0–100, median: 20) attributed to damage, loss or theft. Sixteen departments (29%) reported that prisms were used until damaged or lost. Four departments (7%) were uncertain of their prism usage and could not provide further information.

Conclusions

Majority of eye departments in the UK opt for disposable prisms. This survey shows the perceived cost-effectiveness of disposable prisms is overestimated when the true cost of disinfection and damage is taken into account. Significant cost savings coupled with the low risk of infectivity (if decontaminated properly) should prompt clinicians and ophthalmic departments worldwide to reconsider the use of non-disposable prisms.
Study of phase transition and its dependence on target excitation using fractal properties of pionization process
Authors: Saha Ruma , Deb Argha , Ghosh Dipak
Published: March 2017

In the present work, phase transition and its dependence on target excitation in terms of Levy index and Ginzburg–Landau formalism using fractal properties of pionization process have been studied in 16O–AgBr and 32S–AgBr interactions at incident energies of 60 and 200 AGeV, respectively. For this purpose, the pion data are divided into three sets depending upon the number of grey tracks (ng). Two multifractal moments, namely, G-moment and Takagi moment, have been used as analyzing tools. The study reveals that the pion density distribution possesses multifractal structure for the two types of interactions and at all degrees of target excitation. Different types of phase transitions (thermal and non-thermal) at different energies are indicated by the data but no signal of quark–gluon plasma (QGP) phase transition is obtained.
Design and optimization of a portable LQCD Monte Carlo code using OpenACC
Authors: Bonati Claudio , Coscetti Simone , D’Elia Massimo , Mesiti Michele , Negro Francesco , Calore Enrico , Schifano Sebastiano Fabio , Silvi Giorgio , Tripiccione Raffaele
Published: March 2017

The present panorama of HPC architectures is extremely heterogeneous, ranging from traditional multi-core CPU processors, supporting a wide class of applications but delivering moderate computing performance, to many-core Graphics Processor Units (GPUs), exploiting aggressive data-parallelism and delivering higher performances for streaming computing applications. In this scenario, code portability (and performance portability) become necessary for easy maintainability of applications; this is very relevant in scientific computing where code changes are very frequent, making it tedious and prone to error to keep different code versions aligned. In this work, we present the design and optimization of a state-of-the-art production-level LQCD Monte Carlo application, using the directive-based OpenACC programming model. OpenACC abstracts parallel programming to a descriptive level, relieving programmers from specifying how codes should be mapped onto the target architecture. We describe the implementation of a code fully written in OpenAcc, and show that we are able to target several different architectures, including state-of-the-art traditional CPUs and GPUs, with the same code. We also measure performance, evaluating the computing efficiency of our OpenACC code on several architectures, comparing with GPU-specific implementations and showing that a good level of performance-portability can be reached.
Dark matter and excited weak bosons
Authors: Fritzsch Harald
Published: March 2017

The weak bosons are not elementary gauge bosons, but bound states of two fermions. Here the excitations of the weak bosons and the new fermions are discussed — they might provide the dark matter in the universe.
A Novel Cardiac Arrhythmias Detection Approach for Real-Time Ambulatory ECG Diagnosis
Authors: Zhou Haiying , Zhu Xiancheng , Wang Sishan , Zhou Kui , Ma Zheng , Li Jian , Hou Kun-Mean , De Vaulx Christophe
Published: March 2017

In view of requirements of low-resource consumption and high-efficiency in real-time Ambulatory Electrocardiograph Diagnosis (AED) applications, a novel Cardiac Arrhythmias Detection (CAD) algorithm is proposed. This algorithm consists of three core modules: an automatic-learning machine that models diagnostic criteria and grades the emergency events of cardiac arrhythmias by studying morphological characteristics of ECG signals and experiential knowledge of cardiologists; a rhythm classifier that recognizes and classifies heart rhythms basing on statistical features comparison and linear discriminant with confidence interval estimation; and an arrhythmias interpreter that assesses emergency events of cardia arrhythmias basing on a two rule-relative interpretation mechanisms. The experiential results on off-line MIT-BIH cardiac arrhythmia database as well as online clinical testing explore that this algorithm has 92.8% sensitivity and 97.5% specificity in average, so that it is suitable for real-time cardiac arrhythmias monitoring.
THERMALLY-DRIVEN STRUCTURAL CHANGES OF SPUTTERED COPPER ALUMINUM OXIDE FILMS (Cu–Al2O3) GROWN BY LAYER STACKING METHOD
Authors: LIM WEI QIANG , SUBRAMANI SHANMUGAN , DEVARAJAN MUTHARASU
Published: March 2017

Copper aluminium oxide (Cu–Al2O3) films were synthesized on Si(111) substrates through RF magnetron sputtering by using the layer stacking technique. Cu and Al2O3 targets were used to deposit Cu and Al2O3 thin films under Ar atmosphere, respectively and the deposited films were then annealed under N2 environment at 350[Formula: see text]C, 450[Formula: see text]C and 550[Formula: see text]C for 6[Formula: see text]h. The structural properties of the films were investigated by using X-ray diffraction (XRD) while the surface morphology and topography of the deposited films were examined through Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray (EDX) and Atomic Force Microscopy (AFM). XRD analysis revealed the existence of multiple phases of CuO, Al2O3 and CuAl2O4 in the deposited films on Si(111) substrates. As a result of the annealing effect, the peak intensities of CuO, Al2O3 and CuAl2O4 were found to be increased along with the shifting of peak positions. Williamson–Hall (WH) analysis was also implemented to analyze the structural properties such as crystallite size, stress, strain, and energy density. Based on the three models used in WH analysis, the changes in the crystallite size and strain of the films were indicated to be anomalous with the changes in the annealing temperature. Moreover, the strain of films was also showed to be changed from compressive strain into tensile strain. The FESEM results also indicated the formation of various surface morphologies under various annealing temperatures whereas EDX analysis showed an increased atomic percentage of Cu, Al, and O due to the effect of increase in annealing temperature. The AFM analysis showed that the surface roughness of the deposited films increased with the increase in the annealing temperature.
SURFACE CHARACTERIZATION OF ZrO2/Zr COATING ON Ti6Al4V AND IN VITRO EVALUATION OF CORROSION BEHAVIOR AND BIOCOMPATIBILITY
Authors: WANG RUOYUN , SUN YONGHUA , HE XIAOJING , GAO YUEE , YAO XIAOHONG
Published: March 2017

Biocompatibility is crucial for implants. In recent years, numerous researches were conducted aiming to modify titanium alloys, which are the most extensively used materials in orthopedic fields. The application of zirconia in the biomedical field has recently been explored. In this study, the biological ZrO2 coating was synthesized on titaniumalloy (Ti6Al4V) substrates by a duplex-treatment technique combining magnetron sputtering with micro-arc oxidation (MAO) in order to further improve the corrosion resistance and biocompatibility of Ti6Al4V alloys. The microstructures and phase constituents of the coatings were characterized by scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), the surface wettability was evaluated by contact angle measurements. The results show that ZrO2 coatings are porous with pore sizes less than 2[Formula: see text][Formula: see text]m and consist predominantly of the tetragonal ZrO2 (t-ZrO[Formula: see text] and cubic ZrO2(c-ZrO[Formula: see text] phase. Electrochemical tests indicate that the corrosion rate of Ti6Al4V substrates is appreciably reduced after surface treatment in the phosphate buffer saline (PBS). In addition, significantly improved cell adhesion and growth were observed from the ZrO2/Zr surface. Therefore, the hybrid approach of magnetron sputtering and MAO provides a surface modification for Ti6Al4V to achieve acceptable corrosion resistance and biocompatibility.
ADSORPTION OF H2 AND O2 GASES ON ZnO WURTZOID NANOCRYSTALS: A DFT STUDY
Authors: ABDULSATTAR MUDAR AHMED , ALMAROOF HASAN MUDAR
Published: March 2017

In the present work, we apply wurtzoids nanocrystals with density functional theory to explain the sensitivity of ZnO nanostructures towards hydrogen and oxygen molecules. Present results of ZnO nanocrystals’ sensing to H2 and O2 molecules show a reduction in the energy gap and hence electrical resistivity of ZnO nanocrystals upon attachments of these molecules in agreement with experiment. The results also show that higher temperatures increase the sensitivity of ZnO wurtzoids towards H2 and O2 molecules with the maximum sensitivity approximately at 390[Formula: see text]C and 417[Formula: see text]C for H2 and O2 molecules, respectively, after which it begins to decline according to calculated Gibbs free energy. These temperatures are comparable with experimentally reported operating temperatures of 325[Formula: see text]C and 350[Formula: see text]C for the two gases, respectively. The main reaction mechanism is the dissociation of H2 or O2 molecules on ZnO nanocrystal surface in which hydrogen and oxygen atoms are attached to neighboring Zn and O surface atoms. The removal of these molecules from the surface is also performed by the formation of H2 and O2 molecules prior to their removal from the ZnO nanocrystal surface. Electronic charge transfers to the adsorbed atoms and molecules confirm and illustrate the mechanism mentioned above.
MICROSTRUCTURE AND DRY SLIDING WEAR RESISTANCE OF LASER CLADDING Ti-Al-Si COMPOSITE COATING
Authors: ZHANG H. X. , YU H. J. , CHEN C. Z. , DAI J. J.
Published: March 2017

In order to improve the wear resistance of Ti alloys, different mass ratios of Ti-Si-Al powders were designed to fabricate hard phases reinforced intermetallic matrix composite coatings on the Ti-6Al-4V substrate by laser cladding. The corresponding coatings were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and high resolution transmission microscopy (HRTEM). The HV-1000 hardness tester and MM200 wear test machine were employed to test the hardness and the wear resistance of the composite coatings, respectively. The composite coatings mainly consisted of the reinforcements of Ti5Si3, Ti3AlC2 and Ti7Al5Si[Formula: see text] and the matrix of Ti3Al, TiAl, TiAl3 and [Formula: see text]-Ti. The micro-hardness of the Ti-35Al-15Si coating was from 956 HV[Formula: see text] to 1130 HV[Formula: see text], which was approximately 3–4 times of the substrate and the highest in the three samples. The wear rate of the Ti-35Al-15Si coating was 0.023[Formula: see text]cm3[Formula: see text][Formula: see text][Formula: see text]min[Formula: see text], which was about 1/4 of the Ti-6Al-4V substrate. It was the lowest in the three samples.
Extension theorems for various weight functions over Frobenius bimodules
Authors: Gluesing-Luerssen Heide , Pllaha Tefjol
Published: March 2017

In this paper, we study codes where the alphabet is a finite Frobenius bimodule over a finite ring. We discuss the extension property for various weight functions. Employing an entirely character-theoretic approach and a duality theory for partitions on Frobenius bimodules, we derive alternative proofs for the facts that the Hamming weight and the homogeneous weight satisfy the extension property. We also use the same techniques to derive the extension property for other weights, such as the Rosenbloom–Tsfasman weight.
Minimax robust designs for wavelet estimation of nonparametric regression models with autocorrelated errors
Authors: Selvaratnam Selvakkadunko , Oyet Alwell Julius
Published: March 2017

We discuss the construction of designs for estimation of nonparametric regression models with autocorrelated errors when the mean response is to be approximated by a finite order linear combination of dilated and translated versions of the Daubechies wavelet bases with four vanishing moments. We assume that the parameters of the resulting model will be estimated by weighted least squares (WLS) or by generalized least squares (GLS). The bias induced by the unused components of the wavelet bases, in the linear approximation, then inflates the natural variation of the WLS and GLS estimates. We therefore construct our designs by minimizing the maximum value of the average mean squared error (AMSE). Such designs are said to be robust in the minimax sense. Our illustrative examples are constructed by using the simulated annealing algorithm to select an optimal [Formula: see text]-point design, which are integers, from a grid of possible values of the explanatory or design variable [Formula: see text]. We found that the integer-valued designs we constructed based on GLS estimation, have smaller minimum loss when compared to the designs for WLS or ordinary least squares (OLS) estimation, except when the correlation parameter [Formula: see text] approaches 1.
China and Asia in Global Trade Slowdown
Authors: Hong Gee Hee , Lee Jaewoo , Liao Wei , Seneviratne Dulani
Published: March 2017

Asia and China made disproportionate contributions to the slowdown of global trade growth in 2015. China’s import growth slowed starkly, driven by both external and domestic factors, including a rebalancing of demand. Econometric results point to weak investment and rebalancing as the main causes of the import slowdown. Spillover effects from China’s rebalancing are estimated for some 60 countries using value-added trade data, and are found to be more negative on Asia and commodity exporters than others.
Numerical Analysis of a Compressor Type of Dehumidifier: (I) Fluid Flow
Authors: Duong Xuan Quang , Chung Jae Dong
Published: March 2017

A three-dimensional simulation of a compressor dehumidifier was conducted by applying a porous model for condenser and evaporator, and a moving reference frame for the fan. A physical model was simulated for the unit cell of the actual shape of a fin-tube, and the parameters of viscous resistance and initial resistance were obtained. With these values, the porous model showed close agreement with the physical model within a reasonable computation time. A uniform flow across the evaporator and the condenser is desirable for high performance of the dehumidifier. Surface averaged velocity, standard deviation of velocity, and uniformity were chosen as indicators of the design object. A case study showed that two factors, (i) reducing the space between the evaporator and the condenser and (ii) introducing a cover to reduce the by-passing air flow, have the strongest influence on the air distribution in this dehumidifier.
Understanding and Assessing Nutrition
Authors: Carriquiry Alicia L.
Published: March 2017

Most countries collect short-term food consumption information of individuals on a regular basis. These data, after much analysis and interpretation, are used to assess the nutritional status of population subgroups, design food assistance programs, guide nutritional and food policy, and—in epidemiological applications—uncover associations between diet and health. In this review, we focus on surveillance, a broad term that includes, for example, estimation of nutritional status and evaluation of the adequacy of the diet. From a statistical viewpoint, dietary intake and evaluation questions pose tremendous methodological challenges. Nutrient and food adequacy are defined in terms of long-term intakes, yet we can only practically observe short-term consumption, perhaps over one or two days. Food consumption measurements are noisy and subject to both systematic and random error, and in addition, there are very large day-to-day differences in a person's food consumption. Observed distributions of food and nutrient intake tend to be skewed, with long tails to the right and (in the case of episodically consumed items) with a mass at zero that can represent a large proportion of the distribution. We review the literature on this topic and describe some of the newest questions and proposed methodological solutions. The focus is on the use of large national food consumption surveys to address public policy and research questions, but much of what we discuss is applicable in a broader context.
Smooth muscle cell-specific deletion of Col15a1 unexpectedly leads to impaired development of advanced atherosclerotic lesions
Authors: Durgin Brittany G. , Cherepanova Olga A. , Gomez Delphine , Karaoli Themistoclis , Alencar Gabriel F. , Butcher Joshua T. , Zhou Yu-Qing , Bendeck Michelle P. , Isakson Brant E. , Owens Gary K. , Connelly Jessica J.
Published: March 2017

Atherosclerotic plaque rupture with subsequent embolic events is a major cause of sudden death from myocardial infarction or stroke. Although smooth muscle cells (SMCs) produce and respond to collagens in vitro, there is no direct evidence in vivo that SMCs are a crucial source of collagens and that this impacts lesion development or fibrous cap formation. We sought to determine how conditional SMC-specific knockout of collagen type XV (COL15A1) in SMC lineage tracing mice affects advanced lesion formation given that 1) we have previously identified a Col15a1 sequence variant associated with age-related atherosclerosis, 2) COL15A1 is a matrix organizer enhancing tissue structural integrity, and 3) small interfering RNA-mediated Col15a1 knockdown increased migration and decreased proliferation of cultured human SMCs. We hypothesized that SMC-derived COL15A1 is critical in advanced lesions, specifically in fibrous cap formation. Surprisingly, we demonstrated that SMC-specific Col15a1 knockout mice fed a Western diet for 18 wk failed to form advanced lesions. SMC-specific Col15a1 knockout resulted in lesions reduced in size by 78%, with marked reductions in numbers and proliferating SMCs, and lacked a SMC and extracellular matrix-rich lesion or fibrous cap. In vivo RNA-seq analyses on SMC Col15a1 knockout and wild-type lesions suggested that a mechanism for these effects is through global repression of multiple proatherogenic inflammatory pathways involved in lesion development. These results provide the first direct evidence that a SMC-derived collagen, COL15A1, is critical during lesion pathogenesis, but, contrary to expectations, its loss resulted in marked attenuation rather than exacerbation of lesion pathogenesis.

NEW & NOTEWORTHY We report the first direct in vivo evidence that a smooth muscle cell (SMC)-produced collagen, collagen type XV (COL15A1), is critical for atherosclerotic lesion development. SMC Col15a1 knockout markedly attenuated advanced lesion formation, likely through reducing SMC proliferation and impairing multiple proatherogenic inflammatory processes.
Lung epithelial cell focal adhesion kinase signaling inhibits lung injury and fibrosis
Authors: Wheaton Amanda K. , Agarwal Manisha , Jia Shijing , Kim Kevin K.
Published: March 2017

Progressive pulmonary fibrosis is a devastating consequence of many acute and chronic insults to the lung. Lung injury leads to alveolar epithelial cell (AEC) death, destruction of the basement membrane, and activation of transforming growth factor-β (TGF-β). There is subsequent resolution of the injury and a coordinated and concurrent initiation of fibrosis. Both of these processes may involve activation of similar intracellular signaling pathways regulated in part by dynamic changes to the extracellular matrix. Matrix signaling can augment the profibrotic fibroblast response to TGF-β. However, similar matrix/integrin signaling pathways may also be involved in the inhibition of ongoing TGF-β-induced AEC apoptosis. Focal adhesion kinase (FAK) is an integrin-associated signaling molecule expressed by many cell types. We used mice with AEC-specific FAK deletion to isolate the epithelial aspect of integrin signaling in the bleomycin model of lung injury and fibrosis. Mice with AEC-specific deletion of FAK did not exhibit spontaneous lung injury but did have significantly greater terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling-positive cells (18.6 vs. 7.1) per ×200 field, greater bronchoalveolar lavage protein (3.2 vs. 1.8 mg/ml), and significantly greater death (77 vs. 19%) after bleomycin injury compared with littermate control mice. Within primary AECs, activated FAK directly associates with caspase-8 and inhibits activation of the caspase cascade resulting in less apoptosis in response to TGF-β. Our studies support a model in which dynamic changes to the extracellular matrix after injury promote fibroblast activation and inhibition of epithelial cell apoptosis in response to TGF-β through FAK activation potentially complicating attempts to nonspecifically target this pathway for antifibrotic therapy.
Dynamics of middle cerebral artery blood flow velocity during moderate-intensity exercise
Authors: Billinger Sandra A. , Craig Jesse C. , Kwapiszeski Sarah J. , Sisante Jason-Flor V. , Vidoni Eric D. , Maletsky Rebecca , Poole David C.
Published: March 2017

The dynamic response to a stimulus such as exercise can reveal valuable insights into systems control in health and disease that are not evident from the steady-state perturbation. However, the dynamic response profile and kinetics of cerebrovascular function have not been determined to date. We tested the hypotheses that bilateral middle cerebral artery blood flow mean velocity (MCAV) increases exponentially following the onset of moderate-intensity exercise in 10 healthy young subjects. The MCAVresponse profiles were well fit to a delay (TD) + exponential (time constant, τ) model with substantial agreement for baseline [left (L): 69, right (R): 64 cm/s, coefficient of variation (CV) 11%], response amplitude (L: 16, R: 13 cm/s, CV 23%), TD (L: 54, R: 52 s, CV 9%), τ (L: 30, R: 30 s, CV 22%), and mean response time (MRT) (L: 83, R: 82 s, CV 8%) between left and right MCAVas supported by the high correlations (e.g., MRT r = 0.82, P < 0.05) and low CVs. Test-retest reliability was high with CVs for the baseline, amplitude, and MRT of 3, 14, and 12%, respectively. These responses contrasted markedly with those of three healthy older subjects in whom the MCAVbaseline and exercise response amplitude were far lower and the kinetics slowed. A single older stroke patient showed baseline ipsilateral MCAVthat was lower still and devoid of any exercise response whatsoever. We conclude that kinetics analysis of MCAVduring exercise has significant potential to unveil novel aspects of cerebrovascular function in health and disease.

NEW & NOTEWORTHY Resolution of the dynamic stimulus-response profile provides a greater understanding of the underlying the physiological control processes than steady-state measurements alone. We report a novel method of measuring cerebrovascular blood velocity (MCAv) kinetics under ecologically valid conditions from rest to moderate-intensity exercise. This technique reveals that brain blood flow increases exponentially following the onset of exercise with 1) a strong bilateral coherence in young healthy individuals, and 2) a potential for unique age- and disease-specific profiles.