bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of complex model electrocatalysts in ultra-high vacuum and transfer into the electrolyte for electrochemical IR spectroscopy and other techniques
Authors: Faisal Firas , Bertram Manon , Stumm Corinna , Waidhas Fabian , Brummel Olaf , Libuda Jörg
Published: November 2018

Model studies at complex, yet well-defined electrodes can provide a better understanding of electrocatalytic reactions. New experimental devices are required to prepare such model electrocatalysts with atomic-level control. In this work, we discuss the design of a new setup, which enables the preparation of well-defined electrocatalysts in ultra-high vacuum (UHV) using the full portfolio of surface science techniques. The setup allows for direct transfer of samples from UHV and the immersion into the electrolyte without contact to air. As a special feature, the single crystal sample is transferred without any sample holder, which makes the system easily compatible with most electrochemical in situ methods, specifically with electrochemical infrared reflection absorption spectroscopy, but also with other characterization methods such as single-crystal cyclic voltammetry, differential electrochemical mass spectrometry, or electrochemical scanning tunneling microscopy. We demonstrate the preparation in UHV, the transfer in inert atmosphere, and the immersion into the electrolyte for a complex model catalyst that requires surface science methods for preparation. Specifically, we study Pt nanoparticles supported on well-ordered Co3O4(111) films which are grown on an Ir(100) single crystal. In comparison with reference experiments on Pt(111), the model catalyst shows a remarkably different adsorption and reaction behavior during CO electrooxidation in alkaline environments.
New compact density matrix averaged ANO basis sets for relativistic calculations
Authors: Widmark Per-Olof , Zobel J. Patrick , Vysotskiy Victor P. , Tsuchiya Takashi , Veryazov Valera
Published: November 2018

When including relativistic effects in quantum chemical calculations, basis sets optimized for relativistic Hamiltonians such as the atomic natural orbital-relativistic core-correlated (ANO-RCC) basis set have to be used to avoid large errors that appear upon contraction of the basis set. While the large size of the ANO-RCC basis set in terms of primitive basis functions allows for highly accurate calculations, it also hinders its applicability to large sized systems due to the computational costs. To tackle this problem, a new compact relativistic ANO basis set, the ANO-eXtra Small (XS) basis set, is introduced for elements H–Ca. The number of primitive basis functions in ANO-XS is about half that of the ANO-RCC basis set. This greatly reduces the computational costs in the integral calculations especially when used in combination with Cholesky decomposition. At the same time, the ANO-XS basis set is able to predict molecular properties such as bond lengths and excitation energies with reasonable errors compared to the larger ANO-RCC basis set. The main intention for the ANO-XS basis set is to be used in conjunction with the ANO-RCC basis set for large systems that can be divided with regions demanding different qualities of basis sets. This is exemplified in CASPT2 calculations for an Ir(C3H4N)3 complex, where substituting the larger ANO-RCC for the compact ANO-XS basis set at the ligand atoms yields only minor differences for a large number of excited states compared to calculations employing the ANO-RCC basis set on all atoms. Thus, accurate calculations including relativistic effects for large systems become more affordable with the new ANO-XS basis set.
A nanofilter for fluidic devices by pillar-assisted self-assembly microparticles
Authors: AbdelFatah Tamer , Jalali Mahsa , Mahshid Sara
Published: November 2018

We present a nanofilter based on pillar-assisted self-assembly microparticles for efficient capture of bacteria. Under an optimized condition, we simply fill the arrays of microscale pillars with submicron scale polystyrene particles to create a filter with nanoscale pore diameter in the range of 308 nm. The design parameters such as the pillar diameter and the inter-pillar spacing in the range of 5 μm-40 μm are optimized using a multi-physics finite element analysis and computational study based on bi-directionally coupled laminar flow and particle tracking solvers. The underlying dynamics of microparticles accumulation in the pillar array region are thoroughly investigated by studying the pillar wall shear stress and the filter pore diameter. The impact of design parameters on the device characteristics such as microparticles entrapment efficiency, pressure drop, and inter-pillar flow velocity is studied. We confirm a bell-curve trend in the capture efficiency versus inter-pillar spacing. Accordingly, the 10 μm inter-pillar spacing offers the highest capture capability (58.8%), with a decreasing entrapping trend for devices with larger inter-pillar spacing. This is the case that the 5 μm inter-pillar spacing demonstrates the highest pillar wall shear stress limiting its entrapping efficiency. As a proof of concept, fluorescently labeled Escherichia coli bacteria (E. coli) were captured using the proposed device. This device provides a simple design, robust operation, and ease of use. All of which are essential attributes for point of care devices.
Compositional dependency of double-diffusive layers during binary alloy solidification: Full-field measurements and quantification
Authors: Kumar Virkeshwar , Srivastava Atul , Karagadde Shyamprasad
Published: November 2018

Density variations arising from thermal and compositional gradients in multi-component fluids can lead to natural convection flows. The double-diffusive layer is one such flow phenomenon, commonly observed in oceanic and phase change systems. The solidification of high Prandtl number fluids offers a suitable platform to study multi-diffusive convection owing to continuously evolving temperature and compositional fields. In this work, an experimental investigation was conducted to study the influence of transport phenomena on the double-diffusive layer formation, by performing full-field measurements of concentration and flow velocities during bottom-cooled solidification of a hyper-eutectic aqueous mixture. Using a Mach-Zehnder interferometer, the first-ever real-time, quantitative observations of solutal mixing, plume formation, and the evolution of the double-diffusive layers by forming a stepped compositional distribution have been reported. In addition, the associated flow velocities were measured using the particle image velocimetry technique which clearly characterizes the compositional and thermal natural convection patterns along the vertical and horizontal directions, respectively. The study revealed a life-cycle for the existence of the double-diffusive layers, wherein they undergo onset, development, and disappearance depending on the initial composition, and identified critical Rayleigh numbers for each of these stages. The experimental observations were further supported with analytical scale estimates of the critical length, time, and velocities of the system. The quantitative results elucidate the conditions, including a newly hypothesized threshold composition difference, which led to the formation as well as the disappearance of the layers.
Effect of surface passivation process for AlGaN/GaN HEMT heterostructures using phenol functionalized-porphyrin based organic molecules
Authors: Garg Manjari , Naik Tejas Rajendra , Pathak Ravi , Rao Valipe Ramgopal , Liao Che-Hao , Li Kuang-Hui , Sun Haiding , Li Xiaohang , Singh Rajendra
Published: November 2018

In this work, we investigate an unexplored possibility of passivating the charged surface states on AlGaN/GaN high electron mobility transistor (HEMT) heterostructures by using organic molecules. This has further led to remarkable enhancement in the electrical properties of rectifying metal-semiconductor contacts on AlGaN/GaN. Phenol functionalized Zinc metallated-Tetra Phenyl Porphyrin (Zn-TPPOH) organic molecules were adsorbed on AlGaN/GaN via the solution phase to form a molecular layer (MoL). The presence of the MoL was confirmed using X-ray Photoelectron Spectroscopy (XPS). The thickness of the MoL was assessed as ∼1 nm, using Spectroscopic Ellipsometry and cross-sectional Transmission Electron Microscopy. XPS peak-shift analyses together with Kelvin Probe Force Microscopy revealed that the molecular surface modification reduced the surface potential of AlGaN by approximately 250 meV. Consequently, the Barrier height (ideality factor) of Ni Schottky diodes on AlGaN/GaN was increased (reduced) significantly from 0.91 ± 0.05 eV (2.5 ± 0.31) for Ni/AlGaN/GaN to 1.37 ± 0.03 eV (1.4 ± 0.29) for Ni/Zn-TPPOH/AlGaN/GaN. In addition, a noteworthy decrement in the reverse current from 2.6 ± 1.93 μA to 0.31 ± 0.19 nA at −5 V (∼10 000 times) was observed from Current-Voltage (I-V) measurements. This surface-modification process can be fruitful for improving the performance of AlGaN/GaN HEMTs, mitigating the adverse effects of surface states and polarization in these materials.
Very-long distance propagation of high-energy laser pulse in air
Authors: Wang Jingwei , Yu Wei , Yu M. Y. , Rykovanov Sergey , Ju Jingjing , Luan Shixia , Li Kun , Leng Yuxin , Li Ruxin , Sheng Zheng-Ming
Published: November 2018

Long distance propagation of an energetic laser pulse with intensity slightly below that for multi-photon ionization in air is considered analytically, by noting that in the process, it is mainly the peak region of the pulse that interacts with the air molecules. Similar to that of much shorter femtosecond laser pulses of similar intensity, the affected air becomes slightly ionized and self-consistently forms a co-propagating thin and low-density plasma filament along the axis. It is found that a hundred-Joule-level laser pulse with a relatively large spot radius and pulse duration can propagate (also in the form of a self-consistent filament) tens of kilometers through the atmosphere. Such laser propagation properties should have applications in many areas.
Interface-resolved direct numerical simulations of the interactions between neutrally buoyant spheroidal particles and turbulent channel flows
Authors: Zhu Chenlin , Yu Zhaosheng , Shao Xueming
Published: November 2018

A parallel direct-forcing fictitious domain method is employed to perform interface-resolved numerical simulations of the interactions between neutrally buoyant finite-size spheroidal particles and turbulent channel flows. The effects of the aspect ratio of the spheroidal particles on the turbulence modulation and the rotation of the particles are investigated at the friction Reynolds number of 180, with the ratio of the particle equivalent diameter to the channel width being 0.1, the particle volume fraction ranging from 0.79% to 14.16%, and the particle aspect ratio ranging from 1/3 to 8. Our results show that the flow friction decreases as the prolate particles become more slender or the oblate particles become flatter and is smaller than that of the single-phase flow for the aspect ratio being 1/3 and 8 at the particle volume fraction of 2.36%. Both effects of the low particle volume fraction in the near-wall region and the relatively small Reynolds stress are important to the occurrence of the drag-reduction by the non-spherical particles, and a lower flow drag for the oblate particles compared to the prolate particles at comparable aspect ratios (e.g., 1/3 vs 4) is mainly caused by a lower Reynolds stress contribution. The prolate particles preferentially align their symmetry axes with the streamwise direction, and the oblate particles preferentially align their symmetry axes with the wall-normal direction. However, the most probable orientation of the major axes of both prolate and oblate particles in the near-wall region is not exactly the streamwise direction but has a positive inclination angle with the streamwise direction. Generally the prolate particles have higher spinning velocities and lower tumbling velocities in the entire channel region, compared to the oblate particles.
Two-fluid nonlinear theory of response of tokamak plasma to resonant magnetic perturbation
Authors: Fitzpatrick Richard
Published: November 2018

A comprehensive two-fluid nonlinear theory of magnetic reconnection driven at a single, tearing-stable, rational surface embedded in an H-mode tokamak plasma is presented. The surface is assumed to be resonant with one of the dominant helical harmonics of an applied resonant magnetic perturbation (RMP). The theory described in this paper is highly relevant to the problem of understanding the physics of RMP-induced edge localized mode suppression in tokamak plasmas.
Performance analysis and experimental study of traveling wave type rotary ultrasonic motor in high-rotation environment
Authors: Chen Haipeng , Chen Chao , Wang Junshan , Shi Mingyou
Published: November 2018

In this work, the performance evolution of a traveling wave type rotary ultrasonic motor (TRUM) in a high-rotating environment is studied. The dynamic model of the stator of the TRUM in the centrifugal field is established, and the centrifugal stiffening effect on the stator caused by the centrifugal force is described. Furthermore, the warping deflection of the stator caused by the centrifugal force is analyzed. It is found to change the original contact state and decrease the performance of the TRUM. The contact model between the stator and rotor in the centrifugal field is established. Moreover, the performance model of the TRUM in the centrifugal field is established, and the mechanism and varying trend of the mechanical performance of the TRUM in this condition are analyzed. Finally, the performance test system of the TRUM is set, and the mechanical performance of the TRUM at high angular velocities environment is measured. And the methods to improve the tolerance of the TRUM in the centrifugal field are put forward.
The atomic-scale magnetism of Co2FeAl Heusler alloy epitaxial thin films
Authors: Zhang Xiaoqian , Liu Wenqing , Yan Yu , Niu Wei , Lai Bolin , Zhao Yafei , Wang Wei , He Liang , Meng Hao , Xu Yongbing
Published: November 2018

The atomic-scale magnetism of Co2FeAl Heusler alloys has long been an outstanding question, and with the thickness down to the nanometer scale, this becomes even more sophisticated. Here, we report a direct measurement of the Co2FeAl epitaxial thin films on the GaAs(001) substrate with the in-situ magneto-optic Kerr effect and the synchrotron-based X-ray magnetic circular dichroism techniques. Strong uniaxial magnetic anisotropy has been observed from all thicknesses of the Co2FeAl thin films between 3 unit cells (uc) and 20 uc. A critical thickness of 3 uc has been identified, below which an anti-parallel spin component of the Co atoms occurs. This anti-parallel spin component can be responsible for the significantly reduced magnetic moment and the low spin-polarization near the Fermi level of the Co2FeAl.
Point defects and dopants of boron arsenide from first-principles calculations: Donor compensation and doping asymmetry
Authors: Chae S. , Mengle K. , Heron J. T. , Kioupakis E.
Published: November 2018

We apply hybrid density functional theory calculations to identify the formation energies and thermodynamic charge transition levels of native point defects, common impurities, and shallow dopants in BAs. We find that AsB antisites, boron-related defects such as VB, BAs, and Bi-VB complexes, and antisite pairs are the dominant intrinsic defects. Native BAs is expected to exhibit p-type conduction due to the acceptor-type characteristics of VB and BAs. Among the common impurities we explored, we found that C substitutional defects and H interstitials have relatively low formation energies and are likely to contribute free holes. Interstitial hydrogen is surprisingly also found to be stable in the neutral charge state. BeB, SiAs, and GeAs are predicted to be excellent shallow acceptors with low ionization energy (<0.03 eV) and negligible compensation by other point defects considered here. On the other hand, donors such as SeAs, TeAs SiB, and GeB have a relatively large ionization energy (∼0.15 eV) and are likely to be passivated by native defects such as BAs and VB, as well as CAs, Hi, and HB. The hole and electron doping asymmetry originates from the heavy effective mass of the conduction band due to its boron orbital character, as well as from boron-related intrinsic defects that compensate donors.
High-mobility indirect excitons in wide single quantum well
Authors: Dorow C. J. , Hasling M. W. , Choksy D. J. , Leonard J. R. , Butov L. V. , West K. W. , Pfeiffer L. N.
Published: November 2018

Indirect excitons (IXs) are bound pairs of electrons and holes confined in spatially separated layers. We present wide single quantum well (WSQW) heterostructures with high IX mobility, spectrally narrow IX emission, voltage-controllable IX energy, and long and voltage-controllable IX lifetime. This set of properties shows that WSQW heterostructures provide an advanced platform both for studying basic properties of IXs in low-disorder environments and for the development of high-mobility excitonic devices.
Ability of alleles of PPD1 and VRN1 genes to predict flowering time in diverse Australian wheat (Triticum aestivum) cultivars in controlled environments
Authors: Bloomfield Maxwell T. , Hunt James R. , Trevaskis Ben , Ramm Kerrie , Hyles Jessica
Published: November 2018

Flowering time of wheat (Triticum aestivum L.) is a critical determinant of grain yield. Frost, drought and heat stresses from either overly early or overly late flowering can inflict significant yield penalties. The ability to predict time of flowering from different sowing dates for diverse cultivars across environments in Australia is important for maintaining yield as autumn rainfall events become less reliable. However, currently there are no models that can accurately do this when new cultivars are released. Two major Photoperiod1 and three Vernalisation1 development genes, with alleles identified by molecular markers, are known to be important in regulating phasic development and therefore time to anthesis, in response to the environmental factors of temperature and photoperiod. Allelic information from molecular markers has been used to parameterise models that could predict flowering time, but it is uncertain how much variation in flowering time can be explained by different alleles of the five major genes. This experiment used 13 elite commercial cultivars of wheat, selected for their variation in phenology and in turn allelic variation at the major development genes, and 13 near-isogenic lines (NILs) with matching multi-locus genotypes for the major development genes, to quantify how much response in time to flowering could be explained by alleles of the major genes. Genotypes were grown in four controlled environments at constant temperature of 22°C with factorial photoperiod (long or short day) and vernalisation (±) treatments applied. NILs were able to explain a large proportion of the variation of thermal time to flowering in elite cultivars in the long-day environment with no vernalisation (97%), a moderate amount in the short-day environment with no vernalisation (62%), and less in the short-day (51%) and long-day (47%) environments with vernalisation. Photoperiod was found to accelerate development, as observed in a reduction in phyllochron, thermal time to heading, thermal time to flowering, and decreased final leaf numbers. Vernalisation response was not as great, and rates of development in most genotypes were not significantly increased. The results indicate that the alleles of the five major development genes alone cannot explain enough variation in flowering time to be used to parameterise gene-based models that will be accurate in simulating flowering time under field conditions. Further understanding of the genetics of wheat development, particularly photoperiod response, is required before a model with genetically based parameter estimates can be deployed to assist growers to make sowing-time decisions for new cultivars.
Rural general practice training: experience of a rural general practice team and a postgraduate year two registrar
Authors: Scott-Jones Joseph , Lucas Sarah
Published: November 2018

INTRODUCTION: Undertaking training in rural areas is a recognised way of helping recruit staff to work in rural communities. Postgraduate year two medical doctors in New Zealand have been able to undertake a three-month placement in rural practice as part of their pre-vocational training experience since November 2010. AIM: To describe the experience of a rural general practice team providing training to a postgraduate year two medical trainee, and to describe the teaching experience and range of conditions seen by the trainee. METHODS: A pre- and post-placement interview with staff, and analysis of a logbook of cases and teaching undertaken in the practice. RESULTS: The practice teams experience of having the trainee was positive, and the trainee was exposed to a wide range of conditions over 418 clinical encounters. The trainee received 22.5 hours of formal training over the three-month placement. DISCUSSION: Rural general practice can provide a wide range of clinical experience to a postgraduate year two medical trainee. Rural practices in New Zealand should be encouraged to offer teaching placements at this training level. Exposure to rural practice at every level of training is important to encourage doctors to consider rural practice as a career. KEYWORDS: Education, medical, graduate; general practice; rural health services
Viewpoint: Using the patient-centred medicine clinical framework to better appreciate and explore the many barriers to care in Type 2 diabetes
Authors: Janes Ron , Titchener Janet
Published: November 2018

There are many barriers to diabetes care. This paper explores whether organising these barriers to Type 2 diabetes care within the clinical framework of patient-centred medicine (PCM) enables a better appreciation and conceptualisation of these barriers. The terms 'diabetes', 'barriers to care', 'self-management', 'patient-centred care' and 'outcome assessment' were used to identify 28 articles describing multiple barriers (minimum of three) to care in Type 2 diabetes. Identified barriers were organised within the clinical framework of PCM. Barriers to diabetes care were numerous and diverse, but all could be accommodated within the PCM framework, except for one, that of patient non-compliance (non-adherence). This paternalistic concept contradicts patient autonomy, a key component of the PCM paradigm. Accepting non-adherence as a plausible barrier stops providers from recognising the actual barriers to diabetes self-management. Clinicians need to stop attributing blame for poor disease outcomes on patients, and instead to become partners in identifying and addressing their patients' real barriers to better health by using the practical clinical framework of PCM. KEYWORDS: Diabetes mellitus, type 2; medication adherence; patient-centered care; patient compliance; self care
Testicular hyperthermia increases blood flow that maintains aerobic metabolism in rams
Authors: Rizzoto G. , Hall C. , Tyberg J. V. , Thundathil J. C. , Caulkett N. A. , Kastelic J. P.
Published: November 2018

There is a paradigm that testicular hyperthermia fails to increase testicular blood flow and that an ensuing hypoxia impairs spermatogenesis. However, in our previous studies, decreases in normal and motile spermatozoa after testicular warming were neither prevented by concurrent hyperoxia nor replicated by hypoxia. The objective of the present study was to determine the effects of increasing testicular temperature on testicular blood flow and O2 delivery and uptake and to detect evidence of anaerobic metabolism. Under general anaesthesia, the testicular temperature of nine crossbred rams was sequentially maintained at ~33°C, 37°C and 40°C (±0.5°C; 45min per temperature). As testicular temperature increased from 33°C to 40°C there were increases in testicular blood flow (13.2±2.7 vs 17.7±3.2mLmin−1 per 100g of testes, mean±s.e.m.; P<0.05), O2 extraction (31.2±5.0 vs 47.3±3.1%; P<0.0001) and O2 consumption (0.35±0.04 vs 0.64±0.06mLmin−1 per 100g of testes; P<0.0001). There was no evidence of anaerobic metabolism, based on a lack of change in lactate, pH, HCO3− and base excess. In conclusion, these data challenge the paradigm regarding scrotal–testicular thermoregulation, as acute testicular hyperthermia increased blood flow and tended to increase O2 delivery and uptake, with no indication of hypoxia or anaerobic metabolism.
Spatial ecology of an urban eastern grey kangaroo (Macropus giganteus) population: local decline driven by kangaroo–vehicle collisions
Authors: Brunton Elizabeth A. , Srivastava Sanjeev K. , Burnett Scott
Published: November 2018

Context
As urban landscapes proliferate globally, the need for research into urban wildlife interactions is magnified. The eastern grey kangaroo (Macropus giganteus) is a widespread species commonly involved in wildlife–vehicle collisions in urban areas in Australia. Despite the many urban kangaroo populations and associated conflicts with human activities, few studies have examined how eastern grey kangaroos interact with, and are affected by, the urban matrix.

Aims
The present study aimed to quantify kangaroo demography, movements, habitat utilisation and exposure to risks during a period of intensive urban development in a rapidly changing suburb located in a region undergoing high urban growth rates.

Methods
We utilised foot-based census surveys, global positioning system (GPS) collars, direct observations and reports of wildlife mortality between 2014 and 2016. Geographical information systems (GIS) were used to integrate GPS-tracking data with spatial layers, to quantify kangaroo movements and habitat utilisation.

Key results
The kangaroo population underwent a steep decline and kangaroo–vehicle collisions were the main source of mortality (73%) during the study period. Kangaroos were regularly exposed to the risk of injury, with roads intersecting many parts of their home range. Kangaroos showed positive habitat selection both for lawn and forest habitats and kangaroo movement and presence at the study site were influenced by high-quality forage and cover.

Conclusions
The present research has highlighted that despite areas of suitable habitat remaining, road-kill was a major contributor to localised kangaroo-population decline. We showed that habitat preferences of eastern grey kangaroos in this urban area were consistent with those in natural landscapes.

Implications
The present study is the first to implicate kangaroo–vehicle collisions as the major factor in population decline in kangaroos. These findings can be utilised to guide design and placement of kangaroo–vehicle collision mitigation and assist in planning of urban areas, particularly where kangaroo populations are in decline. Local extirpation of urban kangaroo populations would be greatly reduced by incorporating site-specific kangaroo habitat preferences and existing patterns of kangaroo habitat use in infrastructure planning. The study has contributed to our understanding of the effects of roads on urban wildlife in general and highlighted the importance of landscape permeability.
Cats use hollow papillae to wick saliva into fur
Authors: Noel Alexis C. , Hu David L.
Published: November 2018

Significance

Grooming and cleaning are part of a multibillion dollar industry from carpet cleaning to human hair care to pet grooming. Advancements in this field focus primarily on novel cleaning fluids, with less focus on brush development. This study focuses on the cat, one of nature’s most fastidious groomers. We discover structures on the cat tongue, hollow spines that we call cavo papillae, shared across six species of cats. The papillae wick saliva deep into recesses of the fur, and the flexible base of the papilla permits hairs to be easily removed from the tongue. These multifunctional spines may provide inspiration to soft robotics and biologically inspired technologies for sorting, cleaning, and depositing fluids into fur and arrays of flexible filaments.
Klotho Deficiency Accelerates Stem Cells Aging by Impairing Telomerase Activity
Authors: Ullah Mujib , Sun Zhongjie
Published: November 2018

Understanding the effect of molecular pathways involved in the age-dependent deterioration of stem cell function is critical for developing new therapies. The overexpression of Klotho (KL), an antiaging protein, causes treated animal models to enjoy extended life spans. Now, the question stands: Does KL deficiency accelerate stem cell aging and telomere shortening? If so, what are the specific mechanisms by which it does this, and is cycloastragenol (CAG) treatment enough to restore telomerase activity in aged stem cells? We found that KL deficiency diminished telomerase activity by altering the expression of TERF1 and TERT, causing impaired differentiation potential, pluripotency, cellular senescence, and apoptosis in stem cells. Telomerase activity decreased with KL-siRNA knockdown. This suggests that both KL and telomeres regulate the stem cell aging process through telomerase subunits TERF1, POT1, and TERT using the TGFβ, Insulin, and Wnt signaling. These pathways can rejuvenate stem cell populations in a CD90-dependent mechanism. Stem cell dysfunctions were largely provoked by KL deficiency and telomere shortening, owing to altered expression of TERF1, TGFβ1, CD90, POT1, TERT, and basic fibroblast growth factor (bFGF). The CAG treatment partially rescued telomerase deterioration, suggesting that KL plays a critical role in life-extension by regulating telomere length and telomerase activity.
Association of Age at First Severe Respiratory Syncytial Virus Disease With Subsequent Risk of Severe Asthma: A Population-Based Cohort Study
Authors: Homaira Nusrat , Briggs Nancy , Oei Ju-Lee , Hilder Lisa , Bajuk Barbara , Jaffe Adam , Omer Saad B
Published: November 2018

Objective

In a population-based cohort study, we determined the association between the age at first severe respiratory syncytial virus (RSV) disease and subsequent asthma.

Methods

Incidence rates and rate ratios of the first asthma-associated hospitalization after 2 years of age in children hospitalized for RSV disease at <3 months, 3 to <6 months, 6 to <12 months, and 12–24 months of age were calculated.

Results

The incidence of asthma-associated hospitalization per 1000 child-years among children hospitalized for RSV disease at <3 months of age was 0.5 (95% confidence interval [CI], .2–.7); at 3 to <6 months of age, 0.9 (95% CI,.5–1.3); at 6 to <12 months of age, 2.0 (95% CI, 1.4–2.7); and at 12–24 months of age, 1.7 (95% CI, 1.0–2.5). The rate ratio of hospitalization for asthma was 2–7-fold greater among children hospitalized for RSV disease at ages ≥6 months than that among those hospitalized for RSV disease at ages 0 to <6 months.

Conclusions

Although the burden of RSV disease is highest in children aged <6 months, the burden of subsequent asthma is higher in children who develop RSV disease at ages ≥6 months.
Electronic medical record implementation for a healthcare system caring for homeless people
Authors: Angoff Gerald H , O’Connell James J , Gaeta Jessie M , De Las Nueces Denise , Lawrence Michael , Nembang Sanju , Baggett Travis P
Published: November 2018

Objective

Electronic medical record (EMR) implementation at centers caring for homeless people is constrained by limited resources and the increased disease burden of the patient population. Few informatics articles address this issue. This report describes Boston Health Care for the Homeless Program’s migration to new EMR software without loss of unique care elements and processes.

Materials and methods

Workflows for clinical and operational functions were analyzed and modeled, focusing particularly on resource constraints and comorbidities. Workflows were optimized, standardized, and validated before go-live by user groups who provided design input. Software tools were configured to support optimized workflows. Customization was minimal. Training used the optimized configuration in a live training environment allowing users to learn and use the software before go-live.

Results

Implementation was rapidly accomplished over 6 months. Productivity was reduced at most minimally over the initial 3 months. During the first full year, quality indicator levels were maintained. Keys to success were completing before go-live workflow analysis, workflow mapping, building of documentation templates, creation of screen shot guides, role-based phased training, and standardization of processes. Change management strategies were valuable. The early availability of a configured training environment was essential. With this methodology, the software tools were chosen and workflows optimized that addressed the challenges unique to caring for homeless people.

Conclusions

Successful implementation of an EMR to care for homeless people was achieved through detailed workflow analysis, optimizing and standardizing workflows, configuring software, and initiating training all well before go-live. This approach was particularly suitable for a homeless population.
Plasma Cell–Free DNA Next-Generation Sequencing to Diagnose and Monitor Infections in Allogeneic Hematopoietic Stem Cell Transplant Patients
Authors: Fung Monica , Zompi Simona , Seng Hon , Hollemon Desiree , Parham Adama , Hong David K , Bercovici Sivan , Dolan Estelle , Lien Kathy , Teraoka Justin , Logan Aaron C , Chin-Hong Peter
Published: November 2018

Allogeneic hematopoietic stem cell transplant patients are at risk for common and atypical infections. Superior diagnostics can decrease infection-related morbidity and mortality. A novel plasma cell–free DNA next-generation sequencing test detected an uncommon presentation of Chlamydia trachomatis and recurrent and metastatic complications of Staphylococcus aureus bacteremia before standard microbiology.
Fitkids Treadmill Test: Clinical Utility and Factors Associated With Its Use Among Physical Therapists
Authors: Kotte Elles M W , de Groot Janke F , Winkler Alexander M F , Veenhof Cindy , Takken Tim
Published: November 2018

Background

Although the Fitkids Treadmill Test (FTT) has been validated and normative values are available for healthy 6- to 18-year-old children and adolescents, these facts do not automatically imply uptake of the test in routine practice of physical therapists.

Objective

The objectives of this study were to evaluate the utility of the FTT in different diagnostic groups and to explore potential factors affecting the use of the FTT in clinical practice.

Design

Mixed methods with both quantitative and qualitative data were used in this study.

Methods

Outcome parameters from the FTT were retrieved from the Fitkids database. For evaluation of the utility of the FTT, 2 indicators, exercise duration and maximal effort, were used. An online survey was sent to physical therapists in Fitkids practices to identify factors affecting the use of the FTT in clinical practice.

Results

The proportion of children and adolescents in each of the diagnostic groups who reached the minimal duration of a maximal exercise test ranged from 94% to 100%. The proportion of participants who reached a peak heart rate ≥180 beats/min ranged from 46% for participants with cognitive, psychological, or sensory disorders to 92% for participants with metabolic diseases. The most important facilitator for use of the FTT was the fact that most physical therapists were convinced of the additional value of the FTT. The main barriers were therapists’ attitudes (resistance to change/lack of experience) and, on the environmental level, the absence of a treadmill ergometer in physical therapist practice.

Limitations

Structured interviews would have provided more information on potential factors affecting the use of the FTT in clinical practice.

Conclusions

This study has shown the clinical utility of the FTT in different diagnostic groups in pediatric physical therapist practice. Responding to the factors identified in this study should enable improved uptake of the FTT in clinical practice.
Two Medicaid health plans’ models and motivations for improving colorectal cancer screening rates
Authors: Coury Jennifer K , Schneider Jennifer L , Green Beverly B , Baldwin Laura-Mae , Petrik Amanda F , Rivelli Jennifer S , Schwartz Malaika R , Coronado Gloria D
Published: November 2018

Screening rates for colorectal cancer (CRC) remain low, especially among certain populations. Mailed fecal immunochemical testing (FIT) outreach initiated by U.S. health plans could reach underserved individuals, while solving CRC screening data and implementation challenges faced by health clinics. We report the models and motivations of two health insurance plans implementing a mailed FIT program for age-eligible U.S. Medicaid and Medicare populations. One health plan operates in a single state with ~220,000 enrollees; the other operates in multiple states with ~2 million enrollees. We conducted in-depth qualitative interviews with key stakeholders and observed leadership and clinic staff planning during program development and implementation. Interviews were transcribed and coded using a content analysis approach; coded interview reports and meeting minutes were iteratively reviewed and summarized for themes. Between June and September 2016, nine participants were identified, and all agreed to the interview. Interviews revealed that organizational context was important to both organizations and helped shape program design. Both organizations were hoping this program would address barriers to their prior CRC screening improvement efforts and saw CRC screening as a priority. Despite similar motivations to participate in a mailed FIT intervention, contextual features of the health plans led them to develop distinct implementation models: a collaborative model using some health clinic staffing versus a centralized model operationalizing outreach primarily at the health plan. Data are not yet available on the models’ effectiveness. Our findings might help inform the design of programs to deliver mailed FIT outreach.
Magnaporthe oryzae Abp1, a MoArk1 Kinase-Interacting Actin Binding Protein, Links Actin Cytoskeleton Regulation to Growth, Endocytosis, and Pathogenesis
Authors: Li Lianwei , Zhang Shengpei , Liu Xinyu , Yu Rui , Li Xinrui , Liu Muxing , Zhang Haifeng , Zheng Xiaobo , Wang Ping , Zhang Zhengguang
Published: November 2018

The actin cytoskeleton and actin-coupled endocytosis are conserved cellular processes required for the normal growth and pathogenesis of the rice blast fungus Magnaporthe oryzae. We have previously shown that actin regulating kinase MoArk1 regulates actin dynamics and endocytosis to play a key role in virulence of the fungus. To understand the underlying mechanism, we have characterized the actin-binding protein MoAbp1 that interacts with MoArk1 from M. oryzae. The ΔMoabp1 mutant exhibited delayed endocytosis and defects in growth, host penetration, and invasive growth. Consistent with its putative function associated with actin-binding, MoAbp1 regulates the localization of actin patches and plays a role in MoArk1 phosphorylation. In addition, MoAbp1 interacts with MoCap (adenylyl cyclase–associated protein) affecting its normal patch localization pattern and the actin protein MoAct1 through its conserved domains. Taken together, our results support a notion that MoAbp1 functions as a protein scaffold linking MoArk1, MoCap1, and MoAct1 to regulate actin cytoskeleton dynamics critical in growth and pathogenicity of the blast fungus.
Transmission ofFusarium oxysporumf. sp.fragariaeThrough Stolons in Strawberry Plants
Authors: Pastrana A. M. , Watson D. C. , Gordon T. R.
Published: November 2018

Fusarium wilt of strawberry, caused by the soilborne pathogen Fusarium oxysporum f. sp. fragariae, is a growing threat to the strawberry industry worldwide. Symptoms of the disease typically include stunting, wilting, crown discoloration, and eventual plant death. When Fusarium wilt was discovered in California, the disease was not known to occur anywhere else in North America. Long distance movement of the pathogen would most likely occur through transport of infected plants, which seems plausible if strawberry plants can sustain infections without showing symptoms of disease. The results of this study document that F. oxysporum f. sp. fragariae can move through stolons of infected mother plants and colonize first-generation daughter plants. The pathogen can also move through stolons from first to second-generation daughter plants. Daughter plants of both generations were always symptomless. The pathogen was recovered from both roots and petioles of infected daughter plants. Similar results were obtained for two cultivars known to be susceptible to Fusarium wilt, Albion and Monterey. Transmission through stolons from mother to daughter plants also occurred in the resistant cultivar, San Andreas, but less frequently than in Albion and Monterey.
Understanding How an Invasive Vector Drives Pierce’s Disease Epidemics: Seasonality and Vine-to-Vine Spread
Authors: Daugherty Matthew P. , Almeida Rodrigo P. P.
Published: November 2018

For vector-borne plant pathogens, disease epidemics may be attributable to multiple mechanisms, including introduction of a novel vector whose epidemiological role differs from that of native vectors. In such cases, understanding an exotic vector’s ability to drive an epidemic is central to mitigating its impact. We studied how the invasive glassy-winged sharpshooter (Homalodisca vitripennis Germar) can drive Pierce’s disease outbreaks in vineyards, focusing on its potential to promote vine-to-vine (i.e., secondary) spread of Xylella fastidiosa relative to potential constraints stemming from seasonality in the pathosystem. First, we developed a general vector-borne disease model to understand the consequences for disease dynamics of (i) seasonal acquisition efficiency and (ii) seasonal host recovery from infection. Results of the modeling indicate that these two sources of seasonality could constrain disease incidence, particularly when working in concert. Next, we established a field cage experiment to determine whether H. vitripennis promotes vine-to-vine spread, and looked for evidence of seasonality in spread. Broadly, results from the experiment supported assumptions of the model; there was modest to significant increase in the frequency of pathogen spread over the first season, and those new infections that occurred later in the season were more likely to recover during winter. Ultimately, by the end of the second season, there was not evidence of significant secondary spread, likely due to a combination of seasonal constraints and low transmission efficiency by H. vitripennis. Collectively, these results suggest that, although H. vitripennis may be able to promote vine-to-vine spread in certain contexts, it may not be the key factor explaining its impact. Rather, the ability of H. vitripennis to drive epidemics is likely to be more directly related to its potential to reach higher population densities than native vectors.
Transmission Efficiency of Xylella fastidiosa subsp. pauca Sequence Types by Sharpshooter Vectors after In Vitro Acquisition
Authors: Esteves Mariana B. , Kleina Heloisa T. , Sales Tiago de Melo , Oliveira Thiago P. , de Lara Idemauro A. R. , Almeida Rodrigo P. P. , Coletta-Filho Helvécio D. , Lopes João R. S.
Published: November 2018

Xylella fastidiosa subsp. pauca is genetically diverse and has many vector species. However, there is limited information on vector specificity and efficiency for different sequence types (STs) within the pathogen subspecies. Both STs of X. fastidiosa and vectors differ in their associations with plants; therefore, assessment of vector competence should include the standardized vector acquisition ability of bacteria from artificial diets. This work aimed to adapt and validate an in vitro acquisition system for strains of X. fastidiosa that cause citrus variegated chlorosis, and to compare the transmission efficiency of STs of subsp. pauca by different species of sharpshooter vector. First, acquisition and transmission of ST13 by Bucephalogonia xanthophis and Macugonalia leucomelas was tested using an artificial diet with bacteria grown on minimum defined medium (X. fastidiosa medium) with or without 1% galacturonic acid (GA). Subsequently, four sharpshooter species (B. xanthophis, M. leucomelas, M. cavifrons, and Sibovia sagata) were compared as vectors of ST13 acquired from artificial diets, and four STs of subsp. pauca (11, 13, 65, and 70) were tested for acquisition and transmission by M. leucomelas. The artificial system allowed efficient acquisition and transmission of ST13 to plants, with no differences between the media tested. ST13 was transmitted more efficiently by B. xanthophis and M. leucomelas when compared with M. cavifrons and S. sagata. Different STs influenced acquisition and transmission rates by M. leucomelas. The differences in vector competence, despite the standardized acquisition system, suggest that ST–vector foregut or vector–plant interactions may influence bacterial acquisition, retention and inoculation by the insect.
Fusarium graminearum Chemotype–Spring Wheat Genotype Interaction Effects in Type I and II Resistance Response Assays
Authors: Serajazari Mitra , Hudson Kerin , Kaviani Mina , Navabi Alireza
Published: November 2018

Fusarium head blight (FHB), caused by several Fusarium spp., is a worldwide problem that severely impacts cereal grain yield and poses major risks to human and animal health due to production of the mycotoxin deoxynivalenol (DON) and its acetylated forms, 3-acetyl-DON (3-ADON) and 15-acetyl-DON (15-ADON). Recent studies suggest an inconsistent effect of F. graminearum chemotypes and resistance of wheat (Triticum aestivum) genotypes. To gain insight into the interaction effects of F. graminearum chemotypes and spring wheat genotypes on FHB resistance response, 10 spring wheat genotypes with varying levels of FHB resistance were inoculated with 10 F. graminearum isolates, consisting of 5 3-ADON- and 5 15-ADON-producing isolates and evaluated in type I (spray inoculation) and type II (point inoculation) resistance assays. Wheat genotypes carrying the resistance allele of the Fhb1 quantitative trait locus on chromosome 3BS had lower disease in type II evaluations, regardless of F. graminearum isolate or chemotype. Isolates of F. graminearum were also significantly different for disease aggressiveness. In addition, the 3-ADON-producing isolates were 18% more aggressive than the 15-ADON isolates in type I resistance assays. No difference in aggressiveness of the two chemotypes was observed, when tested in type II resistance assays. There was no interaction effect between F. graminearum chemotypes and spring wheat genotypes, suggesting that screening of germplasm for resistance can be performed with limited number of aggressive isolates.