bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soils beneath different arctic shrubs have contrasting responses to a natural gradient in temperature
Authors: Zhao Qiong , Sundqvist Maja K. , Newman Gregory S. , Classen Aimée T. 
Published: June 2018

AbstractShrubs commonly form islands of fertility and are expanding their distribution and dominance in the arctic due to climate change, yet how soil properties may be influenced when different species of shrubs expand under warmer climates remains less explored. Important plant traits, such as their associated root community, are linked to functionally different and dominant shrub species in the arctic and these traits likely shape biogeochemical cycling in areas of shrub expansion. Using an elevational gradient as a proxy for warming, we explored how biochemical processes beneath two important arctic shrubs varied under warmer (low elevation) and cooler (high elevation) climates. Interestingly, the influence of elevation on biogeochemistry varied between the two shrubs. At the low elevation, Betula nana L., an ectomycorrhizal shrub, had high carbon (C) degrading enzyme activities, and relatively low potential net nitrogen (N) mineralization rates. Conversely, Empetrum nigrum ssp. hermaphroditum Hagerup, an ericoid mycorrhizal dwarf‐shrub, had higher enzyme activities and net N immobilization rates at the higher elevation. Further, E. nigrum ssp. hermpahroditum appeared to have a more closed C and nutrient cycle than B. nana—enzymes degrading C, N, and phosphorus were tightly correlated with each other and with total C and ammonium concentrations in the humus beneath E. nigrum ssp. hermaphroditum, but not beneath B. nana. Our results suggest differences in the warming responses of C and N cycling beneath shrub species across an arctic tundra landscape.
Content of phycoerythrin, phycocyanin, alophycocyanin and phycoerythrocyanin in some cyanobacterial strains: Applications
Authors: Basheva Diyana , Moten Dzhemal , Stoyanov Plamen , Belkinova Detelina , Mladenov Rumen , Teneva Ivanka 
Published: June 2018

AbstractCyanobacteria are unique prokaryotes, which are capable to perform oxygenic photosynthesis. Within these organisms, phycobilisomes (PBS) act as an antenna of the photosynthetic pigment apparatus. Phycobilisomes contain several phycobiliproteins (PBP): phycoerythrin (PE), phycocyanin (PC), allophycocyanin (APC) and phycoerythrocyanin (PEC). The application of phycobiliproteins in the biotechnology, food industry and medicine during the last years is rapidly increasing. The aim of our study was to assess the qualitative and quantitative content of phycoerythrin, phycocyanin, allophycocyanin and phycoerythrocyanin in 14 cyanobacterial strains kept in Plovdiv Algal Culture Collection (PACC) and 4 strains purchased from the Culture Collection of Autotrophic Organisms (CCALA). Our data demonstrated that three strains of Microcoleus autumnalis (PACC 5505, PACC 5522 and PACC 5527) have high potential to produce phycoerythrins (0.132, 0.201 and 0.136 mg/mL, respectively). Similarly, one Microcoleus autumnalis strain (PACC 5522) and one strain of Leptolyngbya boryana (CCALA 084) are suitable for biotechnological production of phycocyanins (0.051 and 0.264 mg/mL, respectively) as well as allophycocyanins (0.102 and 0.171 mg/mL, respectively). In addition, the data about the pigment content could be used as a biochemical marker for taxonomic purposes within the group.
Development of a novel in situ gelling skin dressing: Delivering high levels of dissolved oxygen at pH 5.5.
Authors: Moen Ingrid , Ugland Hege , Strömberg Niklas , Sjöström Eva , Karlson Anders , Ringstad Lovisa , Bysell Helena , Amiry‐Moghaddam Mahmood , Haglerød Camilla 
Published: June 2018

AbstractBackground and aimsWound healing requires appropriate oxygen and pH levels. Oxygen therapy and pH‐modulating treatments have shown positive effects on wound healing. Thus, a dressing, which combines high levels of dissolved oxygen (DO) with the pH of intact skin, may improve wound healing. Our aims were to (1) formulate an in situ gelling dressing with high levels of DO and with the pH level of intact skin, (2) evaluate physical and chemical properties of the dressing, and (3) elucidate basic effects of elevated levels of DO on human skin cells in vitro.MethodsA dressing was formulated with 15 to 16 wt% poloxamer 407, acetate buffer, and oxygenated water. Stability of pH and DO, rheology, and shelf life were analysed. Furthermore, in vitro studies of the effect of increased levels of DO were performed.ResultsAn in situ gelling wound dressing, with a DO concentration ranging between 25 and 35 mg/L and a pH of 5.5, was formulated. The DO concentration was stable above 22 mg/L for at least 30 hours when applied on a surface at 35°C and covered for directed diffusion into the intended wound area. At storage, the dressing had stable pH for 3 months and stable DO concentration over 30 mg/L for 7 weeks. Increasing DO significantly enhanced intracellular ATP in human skin cells, without changing reactive oxygen species production, proliferation rate, or viability.ConclusionThe developed dressing may facilitate wound healing by delivering controlled and stable oxygen levels, providing adjustable pH for optimized healing, and increasing intracellular ATP availability.
Association between high‐grade squamous intraepithelial lesion, age, and number and interval of smears in women in Araçatuba, Brazil
Authors: Xavier‐Júnior Jose Candido Caldeira , Camilo‐Júnior Deolino João , Gardini Ana Paula Hehnes Guedes do Amaral , D’ávilla Solange Correa Garcia Pires , Mattar Neivio José 
Published: June 2018

More than half of patients were underscreened and the number of patients aged 20–24 years with high‐grade squamous intraepithelial lesion was not irrelevant.This article includes a Portuguese translation, available in the Supporting Information section.
Effects of Teriparatide and Vibration on Bone Mass and Bone Strength in People with Bone Loss and Spinal Cord Injury: A Randomized, Controlled Trial
Authors: Edwards W Brent , Simonian Narina , Haider Ifaz T , Anschel Alan S , Chen David , Gordon Keith E , Gregory Elaine K , Kim Ki H , Parachuri Ramadevi , Troy Karen L , Schnitzer Thomas J 
Published: June 2018

ABSTRACT

Spinal cord injury (SCI) is associated with marked bone loss and an increased risk of fracture. We randomized 61 individuals with chronic SCI and low bone mass to receive either teriparatide 20 μg/d plus sham vibration 10 min/d (n = 20), placebo plus vibration 10 min/d (n = 20), or teriparatide 20 μg/d plus vibration 10 min/d (n = 21). Patients were evaluated for 12 months; those who completed were given the opportunity to participate in an open-label extension where all participants (n = 25) received teriparatide 20 μg/d for an additional 12 months and had the optional use of vibration (10 min/d). At the end of the initial 12 months, both groups treated with teriparatide demonstrated a significant increase in areal bone mineral density (aBMD) at the spine (4.8% to 5.5%). The increase in spine aBMD was consistent with a marked response in serum markers of bone metabolism (ie, CTX, P1NP, BSAP), but no treatment effect was observed at the hip. A small but significant increase (2.2% to 4.2%) in computed tomography measurements of cortical bone at the knee was observed in all groups after 12 months; however, the magnitude of response was not different amongst treatment groups and improvements to finite element-predicted bone strength were not observed. Teriparatide treatment after the 12-month extension resulted in further increases to spine aBMD (total increase from baseline 7.1% to 14.4%), which was greater in patients initially randomized to teriparatide. Those initially randomized to teriparatide also demonstrated 4.4% to 6.7% improvements in hip aBMD after the 12-month extension, while all groups displayed increases in cortical bone measurements at the knee. To summarize, teriparatide exhibited skeletal activity in individuals with chronic SCI that was not augmented by vibration stimulation. Without additional confirmatory data, the location-specific responses to teriparatide would not be expected to provide clinical benefit in this population. © 2018 American Society for Bone and Mineral Research.
Harnessing microfluidic streak plate technique to investigate the gut microbiome of Reticulitermes chinensis
Authors: Zhou Nan , Sun Yu‐Tong , Chen Dong‐Wei , Du Wenbin , Yang Hong , Liu Shuang‐Jiang 
Published: June 2018

AbstractThe termite gut microbiome is a model system to investigate microbial interactions and their associations with host. For decades, extensive research with molecular tools and conventional cultivation method has been carried out to define the microbial diversity in termite gut. Yet, many bacterial groups of the termite gut microbiome have not been successfully cultivated in laboratory. In this study, we adapted the recently developed microfluidic streak plate (MSP) technique for cultivation of termite gut microbial communities at both aerobic and anaerobic conditions. We found that 99 operational taxonomic units (OTUs) were cultivable by MSP approach and 18 OTUs were documented first time for termite gut microbiota. Further analysis of the bacterial diversities derived by culture‐dependent MSP approach and culture‐independent 16S rRNA gene typing revealed that both methods have bias in recovery of gut microbiota. In total 396 strains were isolated with MSP technique, and potential new taxa at species and/or genus levels were obtained that were phylogenetically related to Burkholderia, Micrococcus, and Dysgonomonas. Results from this study indicate that MSP technique is applicable for cultivating previously unknown and new microbial groups of termite gut microbiota.
A Fixed versus Weight‐Based Dosing Strategy of Daptomycin May Improve Safety in Obese Adults
Authors: Butterfield‐Cowper Jill M. , Lodise Thomas P. , Pai Manjunath P. 
Published: June 2018

ObjectivesTo compare daptomycin exposures and predicted safety outcomes with a simulated weight‐based and fixed dose in morbidly obese and nonobese subjects.MethodsWe performed a nonparametric population pharmacokinetic analysis of daptomycin concentration‐time data from a prior obese and nonobese kidney function–matched cohort of healthy adult volunteers. Monte Carlo simulations were performed to compare the maximum concentrations (Cmax), minimum concentrations (Cmin), and area under the curve (AUC) with the standard daptomycin 6 mg/kg/day dose or a 500‐mg daily fixed dose in obese and nonobese subjects. The probability of exceeding a daptomycin Cmin target (24.3 mg/L or higher) associated with creatine phosphokinase (CPK) elevations was computed with the two regimens.ResultsNo significant differences were observed in clearance, volume of distribution at steady state, or terminal half‐life between the morbidly obese and nonobese PK models. Daptomycin 6 mg/kg/day resulted in AUC, Cmax, and Cmin values that were ~2‐fold higher in morbidly obese subjects relative to nonobese individuals. In contrast, fixed dosing (500 mg/day) resulted in relatively isometric exposures. The fraction of simulated morbidly obese subjects with a Cmin target associated with CPK elevations was 10.8% with 6 mg/kg/day and 2.0% at the 500 mg/day dosage.ConclusionsWeight‐based maintenance dosing of daptomycin is less likely to yield bioequivalent exposures in morbidly obese subjects and provides credence for the evaluation of fixed maintenance doses across adult body size to improve safety.
Critically assessing the utility of portable lead analyzers for wildlife conservation
Authors: Herring Garth , Eagles‐Smith Collin A. , Bedrosian Bryan , Craighead Derek , Domenech Robert , Langner Heiko W. , Parish Chris N. , Shreading Adam , Welch Alacia , Wolstenholme Rachel 
Published: June 2018

ABSTRACTLead (Pb) exposure in wildlife is a widespread management and conservation concern. Quantitative determination of Pb concentrations in wildlife tissues is the foundation for estimating exposure and risk. Development of low‐cost, portable instruments has improved access and cost‐effectiveness of determining Pb concentrations in blood samples, while also facilitating the ability for wildlife researchers to conduct near real‐time Pb testing. However, these instruments, which use anodic stripping voltammetry (ASV) methodology, may produce an analytical bias in wildlife‐blood Pb concentrations. Additionally, their simplicity invites use without appropriate quality‐assurance–quality‐control measures. Together, these factors can reduce data quality and hamper the ability to evaluate it, raising concerns about use of these instruments to inform important conservation issues. We document the extent to which this bias is addressed in the wildlife toxicology literature, develop quantitative approaches for correcting the bias, and provide recommendations to ensure robust data quality when using these instruments. Of the 25 studies we reviewed that referenced ASV use for determining Pb exposure in wildlife, only 32% acknowledged the existence of bias from the instrument. Importantly, another 20% of the studies actually reported ASV and spectroscopic‐based results together without acknowledging their lack of equivalence. Using a multispecies data set of avian blood Pb concentrations, we found that ASV‐based estimates of paired blood Pb concentrations were 30–38% lower than those from standard spectrometric‐based methods. We provide regression equations based on this analysis of 453 blood samples to allow users of ASV instruments to adjust Pb concentrations to spectrometric‐equivalent values, and propose a series of guidelines to follow when using these instruments to improve data validity. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.
A Comparative Study of Feature Selection Methods for Stress Hotspot Classification in Materials
Authors: Mangal Ankita , Holm Elizabeth A. 
Published: June 2018

AbstractThe first step in constructing a machine learning model is defining the features of the dataset that can be used for optimal learning. In this work, we discuss feature selection methods, which can be used to build better models, as well as achieve model interpretability. We applied these methods in the context of stress hotspot classification problem, to determine what microstructural characteristics can cause stress to build up in certain grains during uniaxial tensile deformation. The results show how some feature selection techniques are biased and demonstrate a preferred technique to get feature rankings for physical interpretations.
An update on adolescent sleep: New evidence informing the perfect storm model☆
Authors: Crowley Stephanie J. , Wolfson Amy R. , Tarokh Leila , Carskadon Mary A. 
Published: June 2018

ABSTRACTThe maturation of sleep regulatory systems during adolescence in combination with psychosocial and societal pressures culminate in a “Perfect Storm” of short and ill‐timed sleep and the associated consequences for many youngsters. This model, first described by Carskadon in 2011, guides our current thinking of adolescent sleep behavior. Since the original description, the field has moved forward with remarkable pace, and this review aims to summarize recent progress and describe how this new work informs our understanding of sleep regulation and sleep behavior during this developmental time frame.
Photoconductive semiconductor switch-based triggering with 1 ns jitter for trigatron
Authors: Wang Langning , Jia Yongsheng , Liu Jinliang 
Published: June 2018

Abstract
Synchronization for multiple-pulse at nanosecond range shows a great value on the power multiplication and synchronous electric fields applications. Nanosecond or sub-ns jitter synchronization is essential for the improved working efficiency of the large amounts of pulse modules and accurate requirements for the power coherent combining applications. This paper presents a trigger generator based on a laser diode-triggered GaAs photoconductive semiconductor switch (PCSS) with low jitter and compact size characteristics. It avoids the high currents that are harmful to high-gain mode PCSSs. In the trigger circuit, a 200 pF capacitor is charged by a microsecond-scale 18 kV pulse and then discharged via the high-gain mode GaAs PCSS to trigger the high-power trigatron switch. When triggered by the ∼10 ns pulse generated by the PCSS, the DC-charged trigatron can operate in the 20–35 kV range with 10 ns rise time and 1 ns delay-time jitter.
Can consumers bank on financial services being secure with GDPR?
Authors: Sydekum Ralf 
Published: June 2018

The face of finance is changing. Everywhere you look, institutions are abandoning the high street and moving to faster, more responsive 24-hour online services to meet customer demand. Yet, as digital engagement increases, hacker groups are changing the game and expanding their footprints of destruction with sophisticated tools to infiltrate operations, attack critical applications and gain access to data. Ralf Sydekum of F5 Networks believes that the EU's General Data Protection Regulation (GDPR) might lead to better data management and greater transparency, and will force organisations to improve their security. On the other hand, businesses that ignore requirements for transparency and fairness will suffer severe reputational and financial consequences
Instability of pressure-driven gas–liquid two-layer channel flows in two and three dimensions
Authors: Ó Náraigh Lennon , Spelt Peter D. M. 
Published: June 2018

We study unstable waves in gas–liquid two-layer channel flows driven by a pressure gradient, under stable stratification, not assumed to be set in motion impulsively. The basis of the study is direct numerical simulation (DNS) of the two-phase Navier–Stokes equations in two and three dimensions for moderately large Reynolds numbers, accompanied by a theoretical description of the dynamics in the linear regime (Orr–Sommerfeld–Squire equations). The results are compared and contrasted across a range of density ratios $r=\unicode[STIX]{x1D70C}_{liquid}/\unicode[STIX]{x1D70C}_{gas}$. Linear theory indicates that the growth rate of small-amplitude interfacial disturbances generally decreases with increasing $r$; at the same time, the cutoff wavenumbers in both streamwise and spanwise directions increase, leading to an ever-increasing range of unstable wavenumbers, albeit with diminished growth rates. The analysis also demonstrates that the most dangerous mode is two-dimensional in all cases considered. The results of a comparison between the DNS and linear theory demonstrate a consistency between the two approaches: as such, the route to a three-dimensional flow pattern is direct in these cases, i.e. through the strong influence of the linear instability. We also characterize the nonlinear behaviour of the system, and we establish that the disturbance vorticity field in two-dimensional systems is consistent with a mechanism proposed previously by Hinch (J. Fluid Mech., vol. 144, 1984, p. 463) for weakly inertial flows. A flow-pattern map constructed from two-dimensional numerical simulations is used to describe the various flow regimes observed as a function of density ratio, Reynolds number and Weber number. Corresponding simulations in three dimensions confirm that the flow-pattern map can be used to infer the fate of the interface there also, and show strong three-dimensionality in cases that exhibit violent behaviour in two dimensions, or otherwise the development of behaviour that is nearly two-dimensional behaviour possibly with the formation of a capillary ridge. The three-dimensional vorticity field is also analysed, thereby demonstrating how streamwise vorticity arises from the growth of otherwise two-dimensional modes.
Long-range optical trapping and binding of microparticles in hollow-core photonic crystal fibre
Authors: Bykov Dmitry S. , Xie Shangran , Zeltner Richard , Machnev Andrey , Wong Gordon K. L. , Euser Tijmen G. , Russell Philip St.J. 
Published: June 2018

AbstractOptically levitated micro- and nanoparticles offer an ideal playground for investigating photon–phonon interactions over macroscopic distances. Here we report the observation of long-range optical binding of multiple levitated microparticles, mediated by intermodal scattering and interference inside the evacuated core of a hollow-core photonic crystal fibre (HC-PCF). Three polystyrene particles with a diameter of 1 µm are stably bound together with an inter-particle distance of ~40 μm, or 50 times longer than the wavelength of the trapping laser. The levitated bound-particle array can be translated to-and-fro over centimetre distances along the fibre. When evacuated to a gas pressure of 6 mbar, the collective mechanical modes of the bound-particle array are able to be observed. The measured inter-particle distance at equilibrium and mechanical eigenfrequencies are supported by a novel analytical formalism modelling the dynamics of the binding process. The HC-PCF system offers a unique platform for investigating the rich optomechanical dynamics of arrays of levitated particles in a well-isolated and protected environment.
Overcoming diffusion-related limitations in semiconductor defect imaging with phonon-plasmon-coupled mode Raman scattering
Authors: Hu Changkui , Chen Qiong , Chen Fengxiang , Gfroerer T. H. , Wanlass M. W. , Zhang Yong 
Published: June 2018

AbstractCarrier diffusion is of paramount importance in many semiconductor devices, such as solar cells, photodetectors, and power electronics. Structural defects prevent such devices from reaching their full performance potential. Although a large carrier diffusion length indicates high material quality, it also implies increased carrier depletion by an individual extended defect (for instance, a dislocation) and obscures the spatial resolution of neighboring defects using optical techniques. For commonly utilized photoluminescence (PL) imaging, the spatial resolution is dictated by the diffusion length rather than by the laser spot size, no matter the spot is at or below the diffraction limit. Here, we show how Raman imaging of the LO phonon-plasmon-coupled mode can be used to recover the intrinsic spatial resolution of the optical system, and we demonstrate the effectiveness of the technique by imaging defects in GaAs with diffraction-limited optics, achieving a 10-fold improvement in resolution. Furthermore, by combining Raman and PL imaging, we can independently and simultaneously determine the spatial dependence of the electron density, hole density, radiative recombination rate, and non-radiative recombination rate near a dislocation-like defect, which has not been possible using other techniques.