bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface tension driven flow of blood in a rectangular microfluidic channel: Effect of erythrocyte aggregation
Authors: Pasias D. , Passos A. , Constantinides G. , Balabani S. , Kaliviotis E.
Published: July 2020

Microfluidic platforms have increasingly been explored for in vitro blood diagnostics and for studying complex microvascular processes. The perfusion of blood in such devices is typically achieved through pressure-driven setups. Surface tension driven blood flow provides an alternative flow delivery option, and various studies in the literature have examined the behavior of blood flow in such fluidic devices. In such flows, the influence of red blood cell (RBC) aggregation, the phenomenon majorly responsible for the non-Newtonian nature of blood, requires particular attention. In the present work, we examine differences in the surface tension driven flow of aggregating and non-aggregating RBC and Newtonian suspensions, in a rectangular microchannel. The velocity fields were obtained using micro-PIV techniques. The analytical solution for blood velocity in the channel is developed utilizing the power law model for blood viscosity. The results showed that RBC aggregation has an impact at the late stages of the flow, observed mainly in the bluntness of the velocity profiles. At the initial stages of the flow, the shearing conditions are found moderately elevated, preventing intense RBC aggregate formation. As the flow decelerates in the channel, RBC aggregation increases, affecting the flow characteristics.
Bifurcation analysis for a two-dimensional peristaltic driven flow of power-law fluid in asymmetric channel
Authors: Ali Nasir , Ullah Kaleem , Rasool Husnain
Published: July 2020

In the present article, the bifurcations of equilibrium points and their streamlined patterns for the peristaltic transport of shear-thinning and shear-thickening fluids through an asymmetric channel are studied by incorporating a power-law model. An exact solution in the wave frame of reference is obtained under the vanishing Reynolds number and long wavelength approximations. A system of non-linear autonomous differential equations is developed to locate the equilibrium points in the flow. The qualitative nature of equilibrium points and their bifurcations are investigated through the dynamical system method. There exist three distinct flow conditions (backward flow, trapping, and augmented flow). It is observed that the shifting of these flow phenomena corresponds to bifurcations where non-hyperbolic degenerate points are conceived. The impacts of various embedded parameters on flow phenomena and their bifurcations are demonstrated through graphical representations. It is found that the trapping phenomenon manifests at a high flow rate for shear-thinning fluids. That is, the backward flow region shrinks for large values of the power-law index. Trapping in mechanical devices can be diminished by enlarging the phase difference of channel walls, while an opposite trend is observed for amplitude ratios. The obtained results are concluded through global bifurcation diagrams. At the end, findings of this analysis are verified by making a comparison with the existing literature.
Polarizable charges in a generalized Born reaction potential
Authors: Poier Pier Paolo , Jensen Frank
Published: July 2020

The generalized Born (GB) model is a fast implicit solvent model that is used as an approximation to the Poisson equation for solutes described by point charges. Due to the simple analytical form, GB models are widely used in molecular dynamics simulations to account for (implicit) solvation effects. In this work, we extend the application of the GB model to polarizable charges by coupling it to the bond capacity (BC) model. The resulting BC–GB model is a non-variational polarization model where the reaction potential is calculated from a GB expression and included in the polarization equation to account for solvation effects. Being non-variational, the BC–GB makes use of a Lagrange formulation for an efficient evaluation of energy gradients. The stability of the algorithm in molecular dynamics simulations is tested in the microcanonical ensemble, and the results show energy conservation as well as small fluctuations. The inclusion of implicit solvation increases the computational cost by only 15% compared to vacuum. Combined with a significant reduction in system size by describing the solvent as a continuum makes the BC–GB model an interesting model for applications requiring the combination of solute polarization and extensive conformational space sampling.
Kinetic energy balance in turbulent particle-laden channel flow
Authors: Pan Qingqing , Xiang Hong , Wang Ze , Andersson Helge I. , Zhao Lihao
Published: July 2020

The present study investigates the influence of particle additives on the transfer, conversion, and dissipation of kinetic energy (KE) of a turbulent gas–solid channel flow. We derived the equations of KE, mean-flow KE, and turbulent KE (TKE) of the particle-laden flow and further performed two-way coupled direct numerical simulations of channel flow laden with four-million particles with Stokes number St = 30 (corresponding to a mass loading ratio of around one) with an Eulerian–Lagrangian approach. We found that, in the unladen flow, more than half of the input energy is directly dissipated in the mean flow, whereas the rest is converted to maintain the turbulence. By contrast, in the laden flow, both mean dissipation and energy supply are comparable with the unladen flow. However, the turbulence production is greatly reduced in the particle-laden flow. Another sink term due to the presence of the particle–fluid interactions corresponds to the rest loss of the total energy supply. The results reveal the particle-induced redistribution of mean KE, which is transferred from the mean flow to particles in the channel core, whereas the flow gains energy from particles in the near-wall region. In total, there is a loss of the mean-flow energy due to the presence of the inertial particles. Regarding TKE balance, the particles, gaining energy from the mean flow, transfer the energy to the fluid across the channel, which contributes around one third of the TKE source. The present results provide a general picture of KE balance of a particle-laden channel flow.
Self-compensation of carbon in HVPE-GaN:C
Authors: Piotrzkowski R. , Zajac M. , Litwin-Staszewska E. , Bockowski M.
Published: July 2020

Electrical properties of carbon-doped halide vapor phase epitaxy-GaN are presented and discussed. Crystals of the highest structural quality and with different carbon concentrations are investigated. Resistivity and Hall measurements as a function of temperature are analyzed in detail. It is found that the concentration of free holes systematically decreases with the increase of carbon concentration. Such behavior results from the fact that the compensation of the carbon acceptor level increases with the carbon concentration. It is accepted that carbon is amphoteric impurity in GaN, creating an acceptor as well as a donor state, which leads to self-compensation. The analysis of existing electron paramagnetic resonance results is extremely important. It enabled us to determine the compensation ratio as a function of carbon concentration. A combination of electron paramagnetic resonance, secondary ion mass spectrometry, and Hall data allowed us to conclude that the acceptor level (CN) exhibits rather significant temperature shift equal to 0.35 meV/K.
Surface defect passivation of Ta3N5 photoanode via pyridine grafting for enhanced photoelectrochemical performance
Authors: Li Fan , Jian Jie , Xu Youxun , Liu Wei , Ye Qian , Feng Fan , Li Can , Jia Lichao , Wang Hongqiang
Published: July 2020

Tantalum nitride (Ta3N5) is a promising photoanode material for photoelectrochemical (PEC) water splitting, while the Ta3N5/Ta photoanode synthesized via general thermal oxidation and nitridation on a Ta foil method usually has serious carrier recombination at the surface, which usually reduces the PEC activities. Herein, we demonstrate an efficient strategy of decorating pyridine, a small organic molecule at the surface of the Ta3N5/Ta photoanode, to alleviate the surface recombination. Such decoration yields a stable photocurrent density of 4.4 mA cm−2 at 1.23 VRHE under AM 1.5G (air mass 1.5 global, 100 mW cm−2) simulated sunlight, which is about 1.4 times higher than that of Ta3N5/Ta without modification, and the photocurrent density still remained ∼100% of its original value after a 5 h stability test. Further characterization of the incident photon-to-current conversion efficiency and absorbed photon-to-current efficiency of the pyridine/Ta3N5/Ta photoanode showed a significant increase to 62% and 72% at 500 nm, respectively. The enhanced pyridine/Ta3N5/Ta PEC performance can be attributed to minimizing the density of nitrogen vacancies due to the passivation of pyridine grafting, which results in the decreased recombination centers and improved charge separation efficiency at the surface. We thus believe that our study of surface passivation by using small organic molecules provides an alternative to address the surface recombination of Ta3N5 based photoelectrodes.
Conditions to optimise the developmental competence of immature equine oocytes
Authors: Metcalf Elizabeth S. , Masterson Keith R. , Battaglia David , Thompson Jeremy G. , Foss Robert , Beck Richard , Cook Nancy L. , O'Leary Thomas
Published: July 2020

Optimising the developmental potential of immature equine oocytes and invitro-produced (IVP) embryos was explored through modifications of established media and holding temperature. In Experiment 1, delaying spontaneous resumption of meiosis through the process of simulated physiological oocyte maturation with the addition of the adenylate cyclase activator forskolin (50µM) and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (100µM) to overnight holding medium before maturation improved blastocyst production (P<0.05). In Experiment 2, the blastocyst production rate was increased significantly when cumulin (100ng mL−1) was added to the overnight holding or culture media (P<0.05). In Experiment 3, immature oocytes held overnight at 16°C before maturation had improved developmental competence than those held at 20°C and 5°C (P<0.05). There was no difference between maturation rates, but blastocyst formation per cleaved oocyte was significantly greater in oocytes held overnight at 16°C than at 20°C or 5°C. Furthermore, blastocyst formation per recovered oocyte and per fertilised oocyte was greater when oocytes were held before maturation at 16°C than at 5°C (P<0.05). In Experiment 4, the addition of sodium ascorbate (AC; 50µg mL−1) to the maturation and/or culture media of oocytes and IVP embryos did not improve blastocyst production, but did appear to lower cleavage rates compared with oocytes and embryos cultured without AC.
Black bear translocations in response to nuisance behaviour indicate increased effectiveness by translocation distance and landscape context
Authors: Bauder Javan M. , Roberts Nathan M. , Ruid David , Kohn Bruce , Allen Maximilian L.
Published: July 2020

Abstract
ContextTranslocation is a widely used non-lethal tool to mitigate human–wildlife conflicts, particularly for carnivores. Multiple intrinsic and extrinsic factors may influence translocation success, yet the influence of release-site landscape context on the success of translocations of wildlife involved in nuisance behaviour is poorly understood. Moreover, few studies of translocated wildlife involved in nuisance behaviour have provided estimates of translocation success under different scenarios.
AimsWe evaluated the role of intrinsic (age, sex) and extrinsic (translocation distance, landscape composition) features on translocation success of American black bears (Ursus americanus) involved in nuisance behaviour and provide spatially explicit predictions of success under different scenarios.
MethodsWe analysed data from 1462 translocations of 1293 bears in Wisconsin, USA, from 1979 to 2016 and evaluated two measures of translocation success: repeated nuisance behaviour and probability of returning to a previous capture location.
Key resultsTranslocation distances ranged from 2 to 235km (mean=57km). Repeated nuisance behaviour was recorded following 13.2% of translocation events (192 of 1457) and was not significantly affected by translocation distance. Bears repeated nuisance behaviour and were recaptured at their previous captures site (i.e. returned) after 64% of translocation events (114 of 178). Return probability decreased with an increasing translocation distance, and yearling bears were less likely to return than were adults. The proportions of agriculture and forest within 75km and 100km respectively, of the release site had positive and negative effects on return probability.
ConclusionsMangers can use bear characteristics and landscape context to improve translocation success. For example, achieving a 10% predicted probability of return would require translocation distances of 49–60km for yearlings in low-agriculture and high-forest landscapes. In contrast, estimated return probability for adults was ≥38% across all translocation distances (0–124km) and almost all landscape contexts.
ImplicationsOur results emphasise the importance of considering the effects of landscape conditions for developing spatially explicit guidelines for maximising translocation success.
Mismatch-tolerant, alignment-free sequence classification using multiple spaced seeds and multiindex Bloom filters
Authors: Chu Justin , Mohamadi Hamid , Erhan Emre , Tse Jeffery , Chiu Readman , Yeo Sarah , Birol Inanc
Published: July 2020

Significance

The sustained growth in data throughput in DNA sequencing platforms surpasses the capacity growth in computing infrastructure. For many biological studies, faster alignment algorithms alleviated some of the computational burden, although not all genomics projects require alignments. Accordingly, recent alignment-free methods are enabling a range of tasks from transcript expression analysis, to metagenome characterization, to local de novo assembly. Although faster than alignment-based methods, these methods are often limited in their sensitivity and memory requirements. We demonstrate that by using spaced-seeds and probabilistic data structures, the sensitivity of alignment-free classification methods can be improved, with memory requirements independent of the seed design and linear to the indexed target size. Furthermore, we showcase the scalable parallelism of this approach.
Adaptation of plasticity to projected maximum temperatures and across climatically defined bioregions
Authors: Sandoval-Castillo Jonathan , Gates Katie , Brauer Chris J. , Smith Steve , Bernatchez Louis , Beheregaray Luciano B.
Published: July 2020

Significance

Adaptation to climate change is expected to be influenced by thermal conditions experienced by species during their evolutionary history. We studied plastic capacity as a target of climatic selection, hypothesizing that populations that evolved under warmer climates have greater plastic adaptive resilience to climate change. This was tested experimentally by comparing upper thermal tolerance and gene expression in fish populations from desert, temperate, and subtropical regions of Australia. Divergent adaptive plastic responses to future climates were found across different bioregions, including in key heat stress genes. The greatest adaptive resilience was shown by the subtropical ecotype, followed by the desert and temperate ecotypes. These results have implications for large-scale assessments of climate impacts and for predictions of species distribution changes.
Mixed-flow design for microfluidic printing of two-component polymer semiconductor systems
Authors: Wang Gang , Feng Liang-Wen , Huang Wei , Mukherjee Subhrangsu , Chen Yao , Shen Dengke , Wang Binghao , Strzalka Joseph , Zheng Ding , Melkonyan Ferdinand S. , Yan Jinhui , Stoddart J. Fraser , Fabiano Simone , DeLongchamp Dean M. , Zhu Meifang , Facchetti Antonio , Marks Tobin J.
Published: July 2020

Significance

Blade coating is a promising methodology for the large-scale printing of polymer electronics, affording nonnegligible microstructure control and properties enhancement. Nevertheless, in two-component systems, the optical/electrical/physical properties are largely dominated by phase separation and domain purity phenomena that are challenging to control. Here, we report a mixed-flow microfluidic printing approach to phase purity control, enabled by a printing blade design based on fluid flow simulations. The result is 50% efficiency enhancement for printed all-polymer solar cells vs. conventional printing and similar enhancements for polymer transistors. Mixed flow is a versatile approach to control domain purity in two-component polymeric semiconductor systems and offers a methodology for printing high-performance soft-matter electronics.
Cytoskeletal organization in isolated plant cells under geometry control
Authors: Durand-Smet Pauline , Spelman Tamsin A. , Meyerowitz Elliot M. , Jönsson Henrik
Published: July 2020

Significance

The cytoskeleton, a network of polymers including microtubules and actin, supports many functions in cells. In plants, the cytoskeleton orientation is an important parameter dictating the direction of cell growth. While light, hormonal, or mechanical signals can affect the cytoskeleton organization, the role of cell geometry remains to be clarified. With a microwell-based approach, we confined plant cells lacking walls in different geometries and found that the cytoskeletons align with the long axis in cells in rectangular wells. Basic geometrical rules of the microtubules are computationally modeled in three dimensions and reveal the role of severing proteins in the shape response, which was observed experimentally. These findings demonstrate how cell geometry feeds back on cytoskeletal organization in plant cells.
Identification of the initial nucleocapsid recognition element in the HIV-1 RNA packaging signal
Authors: Ding Pengfei , Kharytonchyk Siarhei , Waller Alexis , Mbaekwe Ugonna , Basappa Sapna , Kuo Nansen , Frank Heather M. , Quasney Christina , Kidane Aaron , Swanson Canessa , Van Verna , Sarkar Mitali , Cannistraci Emily , Chaudhary Ridhi , Flores Hana , Telesnitsky Alice , Summers Michael F.
Published: July 2020

Significance

Understanding the molecular determinants of retroviral genome packaging is important for drug discovery and development of vectors for gene delivery. We show that the HIV-1 leader, which contains the RNA elements necessary for genome packaging, binds approximately two dozen copies of the cognate NC protein with affinities ranging from ∼40 nM to 1.4 µM. Binding to the four highest-affinity “initial” binding sites occurs with endothermic energetics attributed to NC-induced localized RNA melting. Mutations that stabilize these sites inhibit NC binding in vitro and RNA packaging in transfected cells. A small-molecule inhibitor of RNA packaging binds specifically to the initial NC binding sites and stabilizes the RNA structure. Our findings identify a potential RNA Achilles’ heel for HIV therapeutic development.
The Meaning of Murder: Family Members in the Lives of Juvenile Homicide Offenders
Authors: Deegan Simone Jessica
Published: July 2020

This article underscores the litany of problems that arise for significant others when a juvenile is convicted of murder. It focuses on how these individuals confront the precise nature of their child’s criminality while simultaneously defending themselves against a series of attacks from a variety of intra- and extra-familial sources. A major conclusion of the article is that murderers’ relatives disappear into an eternal vortex of guilt, shame and anger with little, if any, formal or informal support as a means to manage or recover from the debilitating stigma and strain.
Temperature Is Sufficient to Condition a Flavor Preference for a Cold-Paired Solution in Rats
Authors: Kay Kristen E , Martin Laura E , James Kimberly F , Haygood Sashel M , Torregrossa Ann-Marie
Published: July 2020

Increasing evidence suggests that stimulus temperature modifies taste signaling. However, understanding how temperature modifies taste-driven behavior is difficult to separate as we must first understand how temperature alone modifies behavior. Previous work has suggested that cold water is more rewarding and “satiating” than warm water, and water above orolingual temperature is avoided in brief-access testing. We explored the strength of cold water preference and warm water avoidance by asking: (1) if cold temperature alone was sufficient to condition a flavor preference and (2) if avoidance of warm stimuli is driven by novelty. We addressed these questions using custom-designed equipment that allows us to monitor and maintain solution temperatures. We conducted two-bottle preference tests, after pairing Kool-Aid flavors with 10 or 40 °C. Rats preferred the flavor paired with cold temperature, both while it was cold and for 1 day while solutions were presented at 22 °C. We then examined the role of novelty in avoidance of 40 °C. Rats were maintained on 10, 22, or 40 °C water in their home cage to increase familiarity with the temperatures. Rats were then subject to a series of brief-access taste tests to water or sucrose at 10 to 40 °C. Rats that had 40 °C experience licked more to 40 °C water, but not sucrose, during brief-access testing. In a series of two-bottle preference tests, rats maintained on 40 °C water had a decreased preference for 10 °C water when paired opposite 40 °C water. Together, these data contribute to our understanding of orosensory-driven behavior with water at different temperatures.
Search and Contain: Impact of an Integrated Genomic and Epidemiological Surveillance and Response Program for Control of Carbapenemase-producing Enterobacterales
Authors: Lane Courtney R , Brett Judith , Schultz Mark , Gorrie Claire L , Stevens Kerrie , Cameron Donna R M , St George Siobhan , van Diemen Annaliese , Easton Marion , Stuart Rhonda L , Sait Michelle , Peleg Anton Y , Stewardson Andrew J , Cheng Allen C , Spelman Denis W , Waters Mary Jo , Ballard Susan A , Sherry Norelle L , Williamson Deborah A , Romanes Finn , Sutton Brett , Kwong Jason C , Seemann Torsten , Goncalves da Silva Anders , Stephens Nicola , Howden Benjamin P
Published: July 2020

Background

Multiresistant organisms (MROs) pose a critical threat to public health. Population-based programs for control of MROs such as carbapenemase-producing Enterobacterales (CPE) have emerged and evaluation is needed. We assessed the feasibility and impact of a statewide CPE surveillance and response program deployed across Victoria, Australia (population 6.5 million).

Methods

A prospective multimodal intervention including active screening, carrier isolation, centralized case investigation, and comparative pathogen genomics was implemented. We analyzed trends in CPE incidence and clinical presentation, risk factors, and local transmission over the program’s first 3 years (2016–2018).

Results

CPE case ascertainment increased over the study period to 1.42 cases/100 000 population, linked to increased screening without a concomitant rise in active clinical infections (0.45–0.60 infections/100 000 population, P = .640). KPC-2 infection decreased from 0.29 infections/100 000 population prior to intervention to 0.03 infections/100 000 population in 2018 (P = .003). Comprehensive case investigation identified instances of overseas community acquisition. Median time between isolate referral and genomic and epidemiological assessment for local transmission was 11 days (IQR, 9–14). Prospective surveillance identified numerous small transmission networks (median, 2; range, 1–19 cases), predominantly IMP and KPC, with median pairwise distance of 8 (IQR, 4–13) single nucleotide polymorphisms; low diversity between clusters of the same sequence type suggested genomic cluster definitions alone are insufficient for targeted response.

Conclusions

We demonstrate the value of centralized CPE control programs to increase case ascertainment, resolve risk factors, and identify local transmission through prospective genomic and epidemiological surveillance; methodologies are transferable to low-prevalence settings and MROs globally.
Adaptive capacity in the foundation tree species Populus fremontii: implications for resilience to climate change and non-native species invasion in the American Southwest
Authors: Hultine Kevin R , Allan Gerard J , Blasini Davis , Bothwell Helen M , Cadmus Abraham , Cooper Hillary F , Doughty Chris E , Gehring Catherine A , Gitlin Alicyn R , Grady Kevin C , Hull Julia B , Keith Arthur R , Koepke Dan F , Markovchick Lisa , Corbin Parker Jackie M , Sankey Temuulen T , Whitham Thomas G
Published: July 2020

Populus fremontii (Fremont cottonwood) is recognized as one of the most important foundation tree species in the southwestern USA and northern Mexico because of its ability to structure communities across multiple trophic levels, drive ecosystem processes and influence biodiversity via genetic-based functional trait variation. However, the areal extent of P. fremontii cover has declined dramatically over the last century due to the effects of surface water diversions, non-native species invasions and more recently climate change. Consequently, P. fremontii gallery forests are considered amongst the most threatened forest types in North America. In this paper, we unify four conceptual areas of genes to ecosystems research related to P. fremontii’s capacity to survive or even thrive under current and future environmental conditions: (i) hydraulic function related to canopy thermal regulation during heat waves; (ii) mycorrhizal mutualists in relation to resiliency to climate change and invasion by the non-native tree/shrub, Tamarix; (iii) phenotypic plasticity as a mechanism for coping with rapid changes in climate; and (iv) hybridization between P. fremontii and other closely related Populus species where enhanced vigour of hybrids may preserve the foundational capacity of Populus in the face of environmental change. We also discuss opportunities to scale these conceptual areas from genes to the ecosystem level via remote sensing. We anticipate that the exploration of these conceptual areas of research will facilitate solutions to climate change with a foundation species that is recognized as being critically important for biodiversity conservation and could serve as a model for adaptive management of arid regions in the southwestern USA and around the world.
Correlation based snapshot models of the archeomagnetic field
Authors: Mauerberger S , Schanner M , Korte M , Holschneider M
Published: July 2020

For the time stationary global geomagnetic field, a new modelling concept is presented. A Bayesian non-parametric approach provides realistic location dependent uncertainty estimates. Modelling related variabilities are dealt with systematically by making little subjective a priori assumptions. Rather than parametrizing the model by Gauss coefficients, a functional analytic approach is applied. The geomagnetic potential is assumed a Gaussian process to describe a distribution over functions. A priori correlations are given by an explicit kernel function with non-informative dipole contribution. A refined modelling strategy is proposed that accommodates non-linearities of archeomagnetic observables: First, a rough field estimate is obtained considering only sites that provide full field vector records. Subsequently, this estimate supports the linearization that incorporates the remaining incomplete records. The comparison of results for the archeomagnetic field over the past 1000 yr is in general agreement with previous models while improved model uncertainty estimates are provided.
A Randomized Controlled Trial to Investigate Safety and Variability of Egg Excretion After Repeated Controlled Human Hookworm Infection
Authors: Hoogerwerf Marie-Astrid , Koopman Jan Pieter R , Janse Jacqueline J , Langenberg Marijke C C , van Schuijlenburg Roos , Kruize Yvonne C M , Brienen Eric A T , Manurung Mikhael D , Verbeek-Menken Petra , van der Beek Martha T , Westra Inge M , Meij Pauline , Visser Leo G , van Lieshout Lisette , de Vlas Sake J , Yazdanbakhsh Maria , Coffeng Luc E , Roestenberg Meta
Published: July 2020

Background

Controlled human hookworm infections could significantly contribute to the development of a hookworm vaccine. However, current models are hampered by low and unstable egg output, reducing generalizability and increasing sample sizes. This study aims to investigate the safety, tolerability, and egg output of repeated exposure to hookworm larvae.

Methods

Twenty-four healthy volunteers were randomized, double-blindly, to 1, 2, or 3 doses of 50 Necator americanus L3 larvae at 2-week intervals. Volunteers were monitored weekly and were treated with albendazole at week 20.

Results

There was no association between larval dose and number or severity of adverse events. Geometric mean egg loads stabilized at 697, 1668, and 1914 eggs per gram feces for the 1 × 50L3, 2 × 50L3, and 3 × 50L3 group, respectively. Bayesian statistical modeling showed that egg count variability relative to the mean was reduced with a second infectious dose; however, the third dose did not increase egg load or decrease variability. We therefore suggest 2 × 50L3 as an improved challenge dose. Model-based simulations indicates increased frequency of stool sampling optimizes the power of hypothetical vaccine trials.

Conclusions

Repeated infection with hookworm larvae increased egg counts to levels comparable to the field and reduced relative variability in egg output without aggravating adverse events.

Clinical Trials Registration

NCT03257072.
N-glycosylation is involved in stomatal development by modulating the release of active abscisic acid and auxin in Arabidopsis
Authors: Jiao Qingsong , Chen Tianshu , Niu Guanting , Zhang Huchen , Zhou ChangFang , Hong Zhi
Published: July 2020

Asparagine-linked glycosylation (N-glycosylation) is one of the most important protein modifications in eukaryotes, affecting the folding, transport, and function of a wide range of proteins. However, little is known about the roles of N-glycosylation in the development of stomata in plants. In the present study, we provide evidence that the Arabidopsis stt3a-2 mutant, defective in oligosaccharyltransferase catalytic subunit STT3, has a greater transpirational water loss and weaker drought avoidance, accompanied by aberrant stomatal distribution. Through physiological, biochemical, and genetic analyses, we found that the abnormal stomatal density of stt3a-2 was partially attributed to low endogenous abscisic acid (ABA) and auxin (IAA) content. Exogenous application of ABA or IAA could partially rescue the mutant’s salt-sensitive and abnormal stomatal phenotype. Further analyses revealed that the decrease of IAA or ABA in stt3a-2 seedlings was associated with the underglycosylation of β-glucosidase (AtBG1), catalysing the conversion of conjugated ABA/IAA to active hormone. Our results provide strong evidence that N-glycosylation is involved in stomatal development and participates in abiotic stress tolerance by modulating the release of active plant hormones.
Experimental stark widths and shifts of V II spectral lines
Authors: Manrique J , Pace D M Díaz , Aragón C , Aguilera J A
Published: July 2020

We have measured the Stark widths and shifts of V II spectral lines in the wavelength range 2000–4200 Å belonging to 75 multiplets. The spectra are emitted by laser-induced plasmas generated from fused glass discs prepared by borate fusion. The electron density and temperature are in the ranges (0.72–6.5) × 1017 cm−3 and (11 000–14 900) K, respectively. To avoid self-absorption, we have used seven samples with vanadium concentrations selected by the CSigma graph methodology. This has allowed to include strong and weak lines in the study, including resonance and forbidden lines. The experimental widths and shifts are compared with theoretical values available in the literature.
SDSS-IV MaNGA: the [α/Fe] of early-type galaxies
Authors: Liu Yiqing
Published: July 2020

The mean stellar alpha-to-iron abundance ratio ([α/Fe]) of a galaxy is an indicator of galactic star formation time-scale. It is important for understanding the star formation history of early-type galaxies (ETGs) as their star formation processes have basically stopped. Using the model templates that are made by Vazdekis et al., we apply the pPXF-based spectral fitting method to estimate the [α/Fe] of 196 high-signal-to-noise ratio ETGs from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey. The velocity dispersions within 1Re (σe) range from 27 to 270 km s−1. We find a flat relation between the mean [α/Fe] within the 1$R_\mathrm{ e}^{\mathrm{ maj}}$ ellipses and log(σe), even if limiting to the massive sample with log(σe/km s−1) > 1.9. However, the relation becomes positive after we exclude the Mg1 feature in our fits, which agrees with the results from the previous work with other stellar population models, albeit with relatively large scatter. It indicates that the Vazdekis models have self-inconsistency and do not actually cover the observations in Mg1. For reference, we also measure the stellar population radial gradients within 1$R_\mathrm{ e}^{\mathrm{ maj}}$ ellipses. Due to the low resolution of age estimations for old objects and the Mg1 issue, the uncertainties of these gradients cannot be neglected.
From rest-frame luminosity functions to observer-frame colour distributions: tackling the next challenge in cosmological simulations
Authors: Bravo Matías , Lagos Claudia del P , Robotham Aaron S G , Bellstedt Sabine , Obreschkow Danail
Published: July 2020

Galaxy spectral energy distributions (SEDs) remain among the most challenging yet informative quantities to reproduce in simulations due to the large and complex mixture of physical processes that shape the radiation output of a galaxy. With the increasing number of surveys utilizing broad-band colours as part of their target selection criteria, the production of realistic SEDs in simulations is necessary for assisting in survey design and interpretation of observations. The recent success in reproducing the observed luminosity functions (LFs) from far-ultraviolet (UV) to far-infrared (IR), using the state-of-the-art semi-analytic model shark and the SED generator ProSpect, represents a critical step towards better galaxy colour predictions. We show that with shark and ProSpect we can closely reproduce the optical colour distributions observed in the panchromatic Galaxy And Mass Assembly (GAMA) survey. The treatment of feedback, star formation, central–satellite interactions, and radiation reprocessing by dust are critical for this achievement. The first three processes create a bimodal distribution, while dust attenuation defines the location and shape of the blue and red populations. While a naive comparison between observation and simulations displays the known issue of overquenching of satellite galaxies, the introduction of empirically motivated observational errors and classification from the same group finder used in GAMA greatly reduces this tension. The introduction of random reassignment of ${\sim} 15{{\ \rm per\ cent}}$ of centrals/satellites as satellites/centrals on the simulation classification closely resembles the outcome of the group finder, providing a computationally less intensive method to compare simulations with observations.
Early-type galaxies in the Antlia cluster: global properties
Authors: Calderón Juan P , Bassino Lilia P , Cellone Sergio A , Gómez Matías , Caso Juan P
Published: July 2020

We present an extension of our previous research on the early-type galaxy population of the Antlia cluster (d ∼ 35 Mpc), achieving a total coverage of ∼2.6 deg2 and performing surface photometry for ∼300 galaxies, 130 of which are new uncatalogued ones. Such new galaxies mainly fall in the low surface brightness (LSB) regime, but there are also some lenticulars (S0), which support the existence of unique functions that connect bright and dwarf galaxies in the scaling relations. We analyse the projected spatial distribution of galaxies up to a distance of ∼800 kpc from NGC 3268, the adopted centre, as well as the radial velocity distribution and the correlation between galaxy colour and effective radius with the projected spatial distribution. We also obtain the luminosity function of the early-type galaxies and the distribution of stellar masses using the T1-band magnitudes and adopted mass-luminosity ratios. Additionally, we correlate the central galaxy distribution with an X-ray emission map from the literature. Based on the analysis of the radial velocities and galaxy colour distributions, we find that galaxies redder than the colour–magnitude relation (CMR) have a velocity distribution strongly concentrated towards the values of the dominant galaxies and are homogeneously distributed throughout the cluster. Those bluer than the CMR, in turn, have a much more extended radial velocity distribution and are concentrated towards the centre of the cluster. We also identify 12 candidates to ultra diffuse galaxies, which seem to be split into two families, and speculate about their origins in the context of the cluster structure.
Improved nearest-neighbor parameters for the stability of RNA/DNA hybrids under a physiological condition
Authors: Banerjee Dipanwita , Tateishi-Karimata Hisae , Ohyama Tatsuya , Ghosh Saptarshi , Endoh Tamaki , Takahashi Shuntaro , Sugimoto Naoki
Published: July 2020

The stability of Watson–Crick paired RNA/DNA hybrids is important for designing optimal oligonucleotides for ASO (Antisense Oligonucleotide) and CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)–Cas9 techniques. Previous nearest-neighbour (NN) parameters for predicting hybrid stability in a 1 M NaCl solution, however, may not be applicable for predicting stability at salt concentrations closer to physiological condition (e.g. ∼100 mM Na+ or K+ in the presence or absence of Mg2+). Herein, we report measured thermodynamic parameters of 38 RNA/DNA hybrids at 100 mM NaCl and derive new NN parameters to predict duplex stability. Predicted ΔG°37 and Tm values based on the established NN parameters agreed well with the measured values with 2.9% and 1.1°C deviations, respectively. The new results can also be used to make precise predictions for duplexes formed in 100 mM KCl or 100 mM NaCl in the presence of 1 mM Mg2+, which can mimic an intracellular and extracellular salt condition, respectively. Comparisons of the predicted thermodynamic parameters with published data using ASO and CRISPR–Cas9 may allow designing shorter oligonucleotides for these techniques that will diminish the probability of non-specific binding and also improve the efficiency of target gene regulation.
Laxative use in patients with advanced chronic kidney disease transitioning to dialysis
Authors: Sumida Keiichi , Dashputre Ankur A , Potukuchi Praveen K , Thomas Fridtjof , Obi Yoshitsugu , Molnar Miklos Z , Gatwood Justin D , Streja Elani , Kalantar-Zadeh Kamyar , Kovesdy Csaba P
Published: July 2020

Background

Constipation is highly prevalent in patients with chronic kidney disease (CKD), particularly among those with end-stage renal disease (ESRD), partly due to their dietary restrictions, comorbidities and medications. Laxatives are typically used for constipation management; however, little is known about laxative use and its associated factors in patients with advanced CKD transitioning to ESRD.

Methods

In a retrospective cohort of 102 477 US veterans transitioning to dialysis between October 2007 and March 2015, we examined the proportion of patients who filled a prescription for any type of laxative within each 6-month period over 36 months pre- and post-transition to ESRD. Factors associated with laxative use during the last 1-year pre-ESRD period were identified by multivariable logistic regression.

Results

The proportion of patients prescribed laxatives increased as patients progressed to ESRD, peaking at 37.1% in the 6 months immediately following ESRD transition, then remaining fairly stable throughout the post-ESRD transition period. Among laxative users, stool softeners were the most commonly prescribed (∼30%), followed by hyperosmotics (∼20%), stimulants (∼10%), bulk formers (∼3%), chloride channel activator (<1%) and several combinations of these. The use of anticoagulants, oral iron supplements, non-opioid analgesics, antihistamines and opioid analgesics were among the factors independently associated with pre-ESRD laxative use.

Conclusion

The use of laxatives increased considerably as patients neared transition to ESRD, likely mirroring the increasing burden of drug-induced constipation during the ESRD transition period. Findings may provide novel insight into better management strategies to alleviate constipation symptoms and reduce medication requirements in patients with advanced CKD.
Preventing Varicella-Zoster: Advances With the Recombinant Zoster Vaccine
Authors: Ilyas Sahrish , Chandrasekar Pranatharthi H
Published: July 2020

Prevention strategies against varicella zoster infection include chemoprophylaxis with acyclovir and live attenuated zoster vaccine. However, resistance to acyclovir has been problematic, and safety concerns have limited the use of the live attenuated vaccine in immunosuppressed patients. Recombinant zoster vaccine, made available in 2017 for the immunocompetent host, has been evaluated for safety, immunogenicity, and efficacy in several immunocompromised settings as well. The present review compares the live attenuated vaccine and the recombinant zoster vaccine and highlights data on the use of recombinant zoster vaccine in different immunocompromised states. Robust data are available for the safety, immunogenicity, and efficacy of the recombinant vaccine in the autologous stem cell population, particularly among patients with multiple myeloma. The vaccine appears safe and immunogenic in populations including those with cancer (solid tumors and hematologic malignancies), HIV-infected patients, and renal transplant recipients. Efficacy and safety data in other populations are awaited before use of the recombinant vaccine can be more widespread. It is anticipated that an increased use of the recombinant zoster vaccine, particularly in immunosuppressed patients, would lead to a decreased use of acyclovir prophylaxis.
Turkey and Russia: Historical Patterns and Contemporary Trends in Bilateral Relations
Authors: Balta Evren , Çelikpala Mitat
Published: July 2020

Turkish-Russian relations have had a tumultuous history characterized by periods of tensions and conflicts but also intense cooperation. This chapter uses a theoretically guided narrative of Turkish-Russian relations to trace how different factors have combined to yield particular foreign policies and changing patterns of bilateral relations. It argues that despite periods of intense cooperation between the two countries, bilateral relations lack institutionalization and an ability to develop a stable and common perspective on regional and global matters. Consequently, the fate of bilateral relations depends on short-term definitions of the national interest and forces the two countries into a fragile cooperation vulnerable to sudden domestic and geopolitical shifts.
Perspectives on Ethics of AI
Authors: Kuipers Benjamin
Published: July 2020

This chapter describes a computational view of the function of ethics in human society and discusses its application to three diverse examples. First, autonomous vehicles are individually embodied intelligent systems that act as members of society. The ethical knowledge needed by such an agent is not how to choose the lesser evil when confronted by a Deadly Dilemma, but how to recognize the upstream decision point that makes it possible to avoid the Deadly Dilemma entirely. Second, disembodied distributed intelligent systems like Google and Facebook provide valuable services while collecting, aggregating, and correlating vast amounts of information about individual users. With inadequate controls, these corporate systems can invade privacy and do substantial damage through either correct or incorrect inferences. Third, acceptance of the legitimacy of the society by its individual members depends on a general perception of fairness. Rage about unfairness can be directed at individual free-riders or at systematic inequality across the society. Ultimately, the promise of a computational approach to ethical knowledge is not simply ethics for computational devices such as robots. It also promises to help people understand the pragmatic value of ethics as a feedback mechanism that helps intelligent creatures, human and nonhuman, live together in thriving societies.
The Decline of Decent Work in the Twenty-First Century: Implications for Career Development
Authors: Gutowski Ellen R. , Blustein David L. , Kenny Maureen E. , Erby Whitney
Published: July 2020

The aim of this chapter is twofold: (1) to provide an overview of the consequences of the decline in available, quality jobs throughout the world for the individual, community, and society; and (2) to discuss the implications of the changing world of work for career development, with a focus on the psychology of working theory. First, this chapter summarizes existing research and points to the necessity of decent work for well-being. It also reviews the rise in precarious work, resulting in work instability and poverty for a growing number of workers throughout the world. The chapter then discusses consequences of the changing labour market for community and society, articulating why the decline of decent work is a social justice issue. Specifically, the chapter highlights how access to decent work has historically been and continues to be disproportionately out of reach for those who face social and economic marginalization. Finally, the psychology of working theory is presented as a particularly enlightening theoretical contribution for career development work in the twenty-first century. The psychology of working theory asserts the important role of marginalization and economic constraints in hindering access to decent work. This theory also offers several implications for how scholars and practitioners might act to mitigate such deleterious social forces that contribute to poverty and inequality.
Bodies That Don’t Matter, but Labor That Does
Authors: Kathiravelu Laavanya
Published: July 2020

Singapore and Dubai are hypermodern city-states that host large temporary migrant populations. The majority of this group is composed of low-wage workers, migrant men from India who labor under conditions of structural inequality and extreme precarity. While there is a growing literature that discusses the issues of debt bondage and unfair conditions of employment that these men face, there is far less interrogation of the everyday and embodied forms of discrimination they encounter. In taking a deeply embodied and ethnographic approach to understanding the experiences of low-wage migrant male workers in these two metropolises, this chapter demonstrates how they are subject to multiple tropes that, in totality, seek to marginalize and devalue their work and the more intangible “learning” of the city that they undertake as part of the migration trajectory. As a result, despite extended periods of sojourn, they are never fully incorporated into the urban.