bluuebunny/crossref_metadata_2025 huggingface dataset:
DNA-templated silver nanoclusters as an efficient catalyst for reduction of nitrobenzene derivatives: a systematic study
Authors: Ji Zhirun , Ji Yuan , Ding Rui , Lin Lei , Li Bingzhi , Zhang Xing
Published: February 2021

Nitrobenzene compounds are highly toxic pollutants with good stability, and they have a major negative impact on both human health and the ecological environment. Herein, it was found for the first time that fluorescent DNA-silver nanoclusters (DNA-AgNCs) can catalyze the reduction of toxic and harmful nitro compounds into less toxic amino compounds with excellent tolerance to high temperature and organic solvents. In this study, the reduction of p-nitrophenol (4-NP) as a model was systematically investigated, followed by expending the substrate to disclose the versatility of this reaction. This report not only expanded the conditions for utilizing catalytic reduction conditions of DNA-AgNCs as an efficient catalyst in the control of hazardous chemicals but also widened the substrate range of DNA-AgNCs reduction, providing a new angle for the application of noble metal nanoclusters.
Investigation of novel optical and waveguide characteristics for an air–graphene–LiNbO3 system
Authors: Liu Kaijing , Lu Fei , Xu Yuhang , Ma Changdong
Published: February 2021

The optical characteristics of a planar thin film waveguide system composed of air–graphene–LiNbO3 have been investigated. Monolayer or bilayer graphene of high quality are characterized by Raman spectroscopy, scanning electron microscopy and atomic force microscopy. The refractivity and reflectivity of the air–graphene–LiNbO3 system are measured experimentally and compared with those of a LiNbO3 waveguide by the prism coupling method. The reflectivity shows an overall decrease due to the lower transmittance for graphene on the LiNbO3 substrate. The refractivity increases significantly at the wavelength of 1540 nm, which may be attributed to the generation of graphene surface plasmons excited by infrared radiation. A shaped air–graphene–LiNbO3 waveguide is designed and simulated by Mode Solutions. The distribution of an optical field is performed and analyzed. The preparation of the proposed air–graphene–LiNbO3 structure incorporates the commonly used chemical vapor deposition and thin film transfer techniques, and is compatible with existing optoelectronic integration processes, which can be employed for building various optical integrated devices.
Porous carbon/graphite nanosheet/ferromagnetic nanoparticle composite absorbents with adjustable electromagnetic properties
Authors: Zhang Chongyang , Liu Zhi , Xu Pan , Zhang Ying , Yue Xigui
Published: February 2021

With the rapid development of electronic devices and wireless communication tools, it is urgent to design and fabricate low-cost, lightweight and effective electromagnetic absorption materials to solve interference of electromagnetic waves. Herein, a new strategy toward porous carbon/graphite nanosheet/ferromagnetic nanoparticle (PC/GNS/Fe) composites was designed to investigate the influence of crystalline carbon on electromagnetic wave absorption. To begin with, graphite nanosheets (GNSs) were incorporated into the porous polyimide by in situ polymerization, and Fe were added as a magnetic particle source and an agent to regulate the pore size. A series of PC/GNS/Fe composite absorbents were obtained. The direct carbonization of porous polymer precursors was beneficial to the design of the pore structure of materials. A hierarchically porous structure derived from the phase separation process was well maintained in the polyimide pyrolysis process. The results demonstrated that the presence of crystalline carbon could influence the reflection loss value and the frequency range. Hence, the absorbing performance can be optimized by adjusting the pore structure and the content of crystalline carbon in materials, which is conducive to obtaining electromagnetic wave absorption materials with excellent comprehensive performance.
Simulation studies of the interaction of laser radiation with additively manufactured foams
Authors: Milovich J L , Jones O S , Berger R L , Kemp G E , Oakdale J S , Biener J , Belyaev M A , Mariscal D A , Langer S , Sterne P A , Sepke S , Stadermann M
Published: February 2021

The interaction of laser radiation with foams of various porosities and low densities has been the subject of several numerical and experimental studies (Nicolaï et al 2012 Phys. Plasmas
19 113105; Perez et al 2014 Phys. Plasmas
21 023102). In all cases, the modeling of low-Z under-dense foams as uniform gases of equivalent average density using standard radiation-hydrodynamics codes has resulted in heat-front velocities that are considerably faster than those observed experimentally. It has been theoretically conjectured that this difference may be attributed to the breakdown of the foam’s morphology, leading to a dynamics of filament expansion where the ion and electron energy partitions are significantly different from those calculated using the uniform gas model. We found that 3D computer simulations employing a disconnected representation of the foam’s microstructure which allowed for the dynamics of foam element heating, expansion, and stagnation largely supported the theoretical picture. Simulations using this model for laser experiments on under-dense 2 mg cc−1 SiO2 aerogel foams (Mariscal et al 2021 Phys. Plasmas
28 013106) reproduced the experimental data fairly well. We used the validated model in simulations of low-density structured foam-like materials (produced via additive manufacturing) with a variety of morphologies. We found that the log-pile configurations were consistent with the analytical propagation model of Gus’kov et al (2011 Phys. Plasmas
18 103114). Further validation of the model was obtained by simulating experiments performed at the Jupiter Laser Facility using the log-pile and octet-truss foam morphologies. Simulations of the foam–laser interaction using a wave propagation code showed that the microstructure was able to enhance stimulated Brillouin scattering (SBS) by concentrating the light energy into density holes. In turn, this promotes laser filamentation, reducing SBS and bringing the predicted values closer to the experimental data.
Polarization-dependent fast-electron emission in high-temporal-contrast femtosecond laser plasmas
Authors: Ke Lintong , Luan Shixia , Xia Changquan , Yu M Y , Feng Ke , Wang Jingwei , Xu Yi , Leng Yuxin , Wang Wentao , Li Ruxin , Xu Zhizhan
Published: February 2021

The generation and transport of fast electrons play an important role in intense laser interaction with dense plasma. Here, we experimentally study fast electron generation using a planar aluminum target obliquely irradiated at a large incident angle by an ultrashort high-temporal-contrast relativistic laser pulse. Simulations show that for near-relativistic laser intensities, s-polarized lasers above a certain energy threshold can generate energetic electrons (

E
e

>
500
 
keV

) with a high yield, which is different from the case of low laser contrast. It is also shown that the most energetic electrons are emitted along the target’s surface and accelerated to high energies. The key features of the acceleration regimes of lasers with different polarizations are also given.
Laplace DLTS studies of the 0.25 eV electron trap properties in n-GaN
Authors: Kruszewski P , Kaminski P , Kozlowski R , Zelazko J , Czernecki R , Leszczynski M , Turos A
Published: February 2021

The thermal emission rate of electrons from a 0.25 eV trap, widely observed in epitaxial GaN by conventional deep-level transient spectroscopy (DLTS), is investigated by the Laplace DLTS (LDLTS) technique. It is demonstrated that the capacitance relaxation waveforms, from which the properties of this trap have been determined until now by the correlation procedure, contain two exponential components induced by the thermal emission of electrons from two traps with the activation energies of 173 meV and 232 meV. In lightly silicon-doped and carbon-doped epitaxial GaN grown on sapphire substrates, the concentrations of these traps were found to be (5.5–7.2) × 1013 and (1.5–3.2) × 1013 cm−3, respectively. Based on formerly reported experimental results and recently published results of theoretical calculations performed with the implementation of the density functional theory with hybrid functionals, the point defects being a potential source of these traps is proposed. It is shown, that a high resolution of LDLTS gives a new insight into the properties of energy levels related to point defects in epitaxial GaN.
Synaptic behaviour of TiO
x
/HfO2 RRAM enhanced by inserting ultrathin Al2O3 layer for neuromorphic computing
Authors: Panda D , Chu C-A , Pradhan A , Chandrasekharan S , Pattanayak B , Sze S M , Tseng T-Y
Published: February 2021

The synaptic linearity of resistive random-access memory (RRAM) based on TiO
x
/HfO2 improved by inserting an ultrathin Al2O3 layer is investigated. A gradual bipolar switching with a positive set and a negative reset is observed for devices with an Al2O3 layer after an electroforming process. The devices with a 1 nm Al2O3 layer exhibit acceptable reliability with >400 cycles DC endurance with no decrement of the on/off ratio after 104 sec. A remarkable enhancement in the synaptic linearity of potentiation 2.15 and depression 1.52 is achieved in this device. The conduction mechanisms at different current regions of the optimized device are studied. The presence of the Al2O3 layer is confirmed by x-ray photoelectron spectroscopy (XPS) and transmission electron microscopy analyses. About 42% of the oxygen vacancy concentration calculated from the XPS spectra is responsible for the synaptic properties. This synaptic RRAM structure is suitable for upcoming neuromorphic computing devices.
Effect of oxide and interface traps on electrical characteristics of post-deposition annealed HfSiO4/n-Si structures
Authors: Kahraman Aysegul , Yilmaz Ercan
Published: February 2021

This study presents detailed results on the modifications in chemical composition, defective bonds, crystal properties based on x-ray photoelectron spectroscopy (XPS) depth profiles and x-ray diffraction of post-deposition annealed HfSiO4/Si structure. It also leads to a link to defect centers and their effect on the electrical characteristics of MOS capacitors. The HfSiO4 films were deposited on n-Si wafers by RF magnetron sputtering and annealed at room temperature (RT), 300 °C, 700 °C, 900 °C, 1100 °C under N2 ambient. That the atomic concentration values of each element in the oxide did not change significantly depending on the annealing temperature showed that the film was deposited with high homogeneity. It was determined that the shift direction of the binding energies of Hf 4f and O 1s XPS spectra were related to the bonding preference of oxygen rather than its concentration. The increase in Hf–M and Hf–Si oxygen defective bonds decreased the binding energy of the XPS spectra. It was determined from the XPS analyses of amorphous films that Hf–Si and Si–Si oxygen defective bonds may cause the positive charge trapping, resulting in the highest negative charge trapping/positive effective oxide charge density (

Q

eff

) in the 300 °C-MOS capacitor. It was determined that Hf–Hf oxygen defective bonds may be the precursors of negative charge trapping. Interface states only contributed to the dielectric constant (k) in the RT-MOS capacitor. The

Φ

B

(barrier height) values showed that the efficiency of acceptor-like and donor-like interface states changes depending on the frequency.
Flexible piezoelectric device directly assembled through the continuous electrospinning method
Authors: Xue Bin , Zhang Feifei , Zheng Jianming , Xu Chunye
Published: February 2021

Flexible piezoelectric devices could be widely used as important components in the future of electronic skin, foldable screens, robotics, and more. Herein, an integrated flexible piezoelectric device based on polyurethane/silver nanowire (PU/AgNW) electrodes and a piezoelectric polyurethane/polyvinylidene fluoride-trifluoroethylene [PU/P(VDF-TrFE)] layer was assembled directly through the continuous electrospinning method. The sheet resistance of the PU/AgNW electrode is 1.4 Ω sq−1 without tensile strain, and the integrated device exhibits high flexibility, high water-vapor permeability, and excellent work stability. Furthermore, both the PU/AgNW electrode and the piezoelectric device perform with excellent antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), attributed to the incorporation of the silver nanowires. The cross-section SEM image shows a uniform structure of the device, which implies a good connection between electrode layers and the piezoelectric layer. The open-circuit output voltage, short-circuit output current and power density of the device can reach up to 47.9 V, 31.8 μA, and 35.3 μw cm−2, respectively. This study presents a fabrication strategy for both flexible conductive electrodes and piezoelectric devices, and it shows a promising application for monitoring human-activity and harvesting energy from ambient environments.
Soft bidirectional haptic I/O module based on bi-convex patterned PVC gel
Authors: Dong-Soo Choi , Jeong SeongWon , Lee Seok-Han , Ryu SiHo , Kim Sang-Youn
Published: February 2021

In this paper, we propose a bidirectional soft haptic I/O module that not only senses the haptic force but also generates a mechanical vibrotactile sensation. Under external pressure, the distance between the moving plate and lower electrode layer decreases, and the bi-convex patterned poly vinyl chloride (bpPVC) gel gets compressed. These two motions make the capacitance of the proposed module change. Moreover, the application of external electric field (EF) creates an electrostatic force between the upper and lower electrode layers and generates the electric-field-induced deformation of the bpPVC gel simultaneously. As soon as the external EF disappears, the proposed module regains its original shape through the elastic restoring forces of the bpPVC gel and planar springs. Therefore, the applied AC voltage makes the proposed module vibrate. The dielectric and mechanical properties of the bpPVC gel are measured to investigate the optimal weight ratio of the PVC and plasticizers. Experiments are conducted to measure the haptic sensing and actuating performance of the proposed method. The capacitance of the proposed haptic I/O module increases from 17.4 pF to 54.8 pF when the external pressure varied from 0 kPa to 100 kPa. On the other hand, the haptic output of the proposed I/O module is observed as 0.81g (g = 9.8 m s−2) at 100 Hz. The results clearly indicate that the proposed haptic I/O module not only senses the static and dynamic pressure but also controls the amplitude of vibrotactile sensation. Owing to its mechanically soft structure, we expect that the proposed haptic I/O module has the potential to be applied or attached to various flexible/soft devices or the human body.
Evaluation of similarities and differences of LiTaO3 and LiNbO3 based on high-T-conductivity, nonlinear optical fs-spectroscopy and ab initio modeling of polaronic structures
Authors: Krampf A , Imlau M , Suhak Y , Fritze H , Sanna S
Published: February 2021

Different aspects of ferroelectric LiTaO3 (LT) such as polaronic defects, optical response and electrical conductivity are investigated by the most recent theoretical and experimental approaches. Comparing the results with the state-of-the-art knowledge of the widely studied LiNbO3 (LN), we evaluate the general assumption that there is little difference between the aforementioned properties of LT and LN. First-principles calculations reveal the existence of point defects in LT qualitatively compatible with the polaronic picture established in LN. Though, peculiar differences with respect to the individual binding energies and polaronic deformation can be revealed. Accordingly, (sub-)picosecond transient absorption measurements show pronounced differences in the kinetics in the sub-ps time domain of small polaron formation and, even more pronounced, in the long-term evolution identified with small polaron hopping. In contrast, (sub-)ps transient luminescence, attributed to the relaxation of self-trapped excitons in LN, shows very similar kinetics. Electrical conductivity measurements are performed in air as function of temperature. Up to about 600 °C they demonstrate similar temperature dependence for the two materials, from which rather comparable activation energies can be extracted. However, in the high-temperature range from about 600 °C to 920 °C both materials show noticeable differences. The results suggest that the fundamental microscopic understanding of LN can be in part transferred to LT. However, due to differences in structure, energetic landscape and temperature behavior, discrepancies between the two materials bear a striking potential for novel applications, even at high temperatures.
Recrystallization-mediated crack initiation in tungsten under simultaneous high-flux hydrogen plasma loads and high-cycle transient heating
Authors: Li Y. , Morgan T.W. , Vermeij T. , Vernimmen J.W.M. , Loewenhoff Th. , Hoefnagels J.P.M. , van Dommelen J.A.W. , Wirtz M. , De Temmerman G. , Verbeken K. , Geers M.G.D.
Published: February 2021

Tungsten and tungsten-based alloys are the leading material choices for the divertor plasma facing components (PFCs) in future fusion reactors. Recrystallization may occur when they undergo high heat loads, drastically modifying the predesigned grain structures and the associated desired mechanical properties. However, the influence of recrystallization on the thermal fatigue behavior of tungsten PFCs still remains unclear. In this study, ITER-grade tungsten was simultaneously exposed to a high-flux hydrogen plasma (∼5 × 1024 m−2 s−1) and high-cycle (104–105) transient heat loads in the linear plasma device Magnum-PSI. By correlating the surface temperature distribution, obtained by analyzing temperature-, wavelength-, and surface-dependent emissivity, and the surface modifications of the plasma exposed specimens, the crack initiation heat flux factor threshold was found to be ∼2 MW m−2 s0.5 (equivalently, ∼0.07 MJ m−2 for a 1 ms pulse). Based on electron backscatter diffraction analyses of cross-sections near the crack initiation sites, faster recrystallization kinetics near the surface compared to literature was observed and the surface cracks preferentially initiated at high angle grains boundaries (HAGBs). Upon recrystallization, the yield strength decreases which entails increasing cyclic plastic strains. The HAGBs fraction is increased, which constrains the transfer of plastic strains at grain boundaries. The recrystallization decreases the dislocation density, which promotes heterogeneous deformation. All these mechanisms explain the reduced crack initiation threshold of recrystallized tungsten compared to its as-received counterpart. The results provide new insights into the structural failure mechanisms in tungsten PFCs exposed to extreme fusion plasmas.
Onset of tearing modes in plasma termination on JET: the role of temperature hollowing and edge cooling
Authors: Pucella G. , Buratti P. , Giovannozzi E. , Alessi E. , Auriemma F. , Brunetti D. , Ferreira D.R. , Baruzzo M. , Frigione D. , Garzotti L. , Joffrin E. , Lerche E. , Lomas P.J. , Nowak S. , Piron L. , Rimini F. , Sozzi C. , Van Eester D. , JET Contributors
Published: February 2021

In this work the onset of tearing modes in the termination phase of plasma pulses on JET is investigated. It is shown that the broadening or the shrinking of the current density profile, as a consequence of a core hollowing or an edge cooling of the electron temperature profile, strongly increases the probability of destabilizing a 2/1 tearing mode also in absence of an external trigger (e.g. a sawtooth crash). Two parameters are defined to highlight changes in the shape of the temperature profile that can lead to MHD instabilities and an empirical stability diagram is introduced into the space of the two new parameters. A large data-set of pulses carried out in the high-current scenario at JET with ITER-like wall is analyzed and criteria for the development of disruption alerts based on the two risk indicators for MHD instabilities are discussed, taking into account the different dynamics of the observed phenomena leading to the onset of 2/1 tearing modes.
Pendulum beams: optical modes that simulate the quantum pendulum
Authors: Galvez E J , Auccapuclla F J , Qin Y , Wittler K L , Freedman J M
Published: February 2021

The wave equation of electromagnetism, the Helmholtz equation, has the same form as the Schrödinger equation, and so optical waves can be used to study quantum mechanical problems. The electromagnetic wave solutions for non-diffracting beams lead to the two-dimensional Helmholtz equation. When expressed in elliptical coordinates the solution of the angular part is the same as the Schrödinger equation for the simple pendulum. The resulting optical eigenmodes, Mathieu modes, have an optical Fourier transform with a spatial intensity distribution that is proportional to the quantum mechanical probability for the pendulum. Comparison of Fourier intensities of eigenmodes are in excellent agreement with calculated quantum mechanical probabilities of pendulum stationary states. We further investigate wave-packet superpositions of a few modes and show that they mimic the libration and the nonlinear rotation of the classical pendulum, including revivals due to the quantized nature of superpositions. The ability to ‘dial a wavefunction’ with the optical modes allows the exploration of important aspects of quantum wave-mechanics and the pendulum that may not be possible with other physical systems.
The instrument transfer function for optical measurements of surface topography
Authors: de Groot Peter J
Published: February 2021

For optical measurements of areal surface topography, the instrument transfer function (ITF) quantifies height response as a function of the lateral spatial frequency content of the surface. The ITF is used widely for optical full-field instruments such as Fizeau interferometers, confocal microscopes, interference microscopes, and fringe projection systems as a more complete way to characterize lateral resolving power than a single number such as the Abbe limit. This paper is a comprehensive review of the ITF, including standardized definitions, ITF prediction using theoretical simulations, common uses, limitations, and evaluation techniques using material measures.
Association between everyday walking activity, objective and perceived risk of falling in older adults
Authors: Jansen Carl-Philipp , Klenk Jochen , Nerz Corinna , Todd Chris , Labudek Sarah , Kramer-Gmeiner Franziska , Becker Clemens , Schwenk Michael
Published: February 2021

Background

older persons can be grouped according to their objective risk of falling (ORF) and perceived risk of falling (PRF) into ‘vigorous’ (low ORF/PRF), ‘anxious’ (low ORF/high PRF), ‘stoic’ (high ORF/low PRF) and ‘aware’ (high ORF/PRF). Sensor-assessed daily walking activity of these four groups has not been investigated, yet.

Objective

we examined everyday walking activity in those four groups and its association with ORF and PRF.

Design

cross-sectional.

Setting

community.

Subjects

N = 294 participants aged 70 years and older.

Methods

ORF was determined based on multiple independent risk factors; PRF was determined based on the Short Falls Efficacy Scale-International. Subjects were allocated to the four groups accordingly. Linear regression was used to quantify the associations of these groups with the mean number of accelerometer-assessed steps per day over 1 week as the dependent variable. ‘Vigorous’ was used as the reference group.

Results

average number of steps per day in the four groups were 6,339 (‘vigorous’), 5,781 (‘anxious’), 4,555 (‘stoic’) and 4,528 (‘aware’). Compared with the ‘vigorous’, ‘stoic’ (−1,482; confidence interval (CI): −2,473; −491) and ‘aware’ (−1,481; CI: −2,504; −458) participants took significantly less steps, but not the ‘anxious’ (−580 steps; CI: −1,440; 280).

Conclusion

we have integrated a digital mobility outcome into a fall risk categorisation based on ORF and PRF. Steps per day in this sample of community-dwelling older persons were in accordance with their ORF rather than their PRF. Whether this grouping approach can be used for the specification of participants’ needs when taking part in programmes to prevent falls and simultaneously promote physical activity remains to be answered in intervention studies.
The Impact of Epidemiology on Fertility and Prenatal Care During the COVID-19 Pandemic
Authors: Dionne-Odom Jodie , Klipstein Sigal
Published: February 2021

The emergence of the novel coronavirus disease 2019 (COVID-19) presented the field of reproductive medicine with many challenges due to an absence of data to guide clinical decision-making and inform patient counseling and management in the early days of the pandemic. Epidemiological studies rapidly filled key gaps in our understanding of the susceptibility of reproductive-aged women to the virus, transmission dynamics during pregnancy and lactation, and the effect of infection during the prenatal, pregnancy, and postpartum periods. This data guided the development of clinical guidelines written by the American Society for Reproductive Medicine as patients and clinicians navigated reproductive decisions during a time of uncertainty. We present a review of epidemiologic studies published between March and December 2020 that have directly informed prenatal and fertility care during the COVID-19 pandemic. Despite a significant increase in our knowledge base over the past year, many questions remain about the impact of COVID-19 on conception, pregnancy, fetal development, and lactation. In the future, a commitment toward inclusion of pregnant persons and those attempting pregnancy in the design of observational and interventional trials is necessary to gain earlier insights about outcomes and assist providers and patients in making data-driven decisions.
Impact of Anti-hypertensive Therapy in the Sexual Health of Men and Women: An Analysis From the SPRINT Trial
Authors: Ferreira João Pedro , Böhm Michael , Rossignol Patrick , Zannad Faiez
Published: February 2021

BACKGROUND

Pharmacologic anti-hypertensive (HT) treatment reduces cardiovascular risk. However, many patients are nonadherent due to perceived or real concern about sexual-related side effects.

METHODS

In a subset of the SPRINT (a randomized trial of intensive vs. standard blood-pressure control) trial, we sought to investigate the impact of anti-HT treatment on sexual activities of men and women over time, and whether this impact varied with a more or less intensive anti-HT therapy. Random-effects models for panel/longitudinal data.

RESULTS

Among the 1,268 men and 613 women included in this substudy, 862 (68%) men and 178 (29%) women declared to be engaged in sexual activity of any kind. Compared with women and men not engaged in sexual activity, those engaged were younger (64 vs. 69 years for women and 65 vs. 75 years for men). Women had an overall low satisfaction with their sexual life but their sexual health was not affected by anti-HT therapy over time nor modified by an intensive treatment. Men’s erections were slightly deteriorated over time (−0.1 to −0.2 points on a scale of 1 (worse) to 5 (best); P < 0.05), but were not aggravated by intensive anti-HT therapy (P > 0.05 for all).

CONCLUSIONS

Self-declared women’s sexual health was not affected by an intensive anti-HT therapy. Men reported a slight deterioration in the quality of their erections, irrespective of standard or intensive therapy. These findings may help reassuring patients about the sexual safety of intensive anti-HT therapy, therefore, potentially improving adherence to intensive therapy strategy.
A Longitudinal Mediation Model of Negative Emotionality, Coping Motives and Drinking Intensity Among Individuals Receiving Community Treatment for Alcohol Use Disorder
Authors: Votaw Victoria R , Stein Elena R , Witkiewitz Katie
Published: February 2021

Aims

Negative emotionality is a key domain in frameworks measuring heterogeneity in alcohol use disorder (AUD), such as the Addictions Neuroclinical Assessment (ANA). Recent research has examined the construct validity of the ANA negative emotionality domain, but has not examined whether this domain demonstrates predictive validity for drinking outcomes. In this study, we examined the association between self-reported negative emotionality at baseline and drinking intensity 1 year following AUD treatment initiation. We also assessed whether coping motives for alcohol use at 6 months following treatment initiation and changes in coping motives mediated this association.

Methods

This was a secondary data analysis of a multisite prospective study of individuals entering AUD treatment (n = 263; 61.6% male; mean age = 33.8). Measures of coping motives and drinking intensity captured those who experienced a lapse to drinking. The associations between the ANA negative emotionality domain, coping motives and drinking intensity over time were assessed using a latent growth curve mediation model.

Results

The ANA negative emotionality domain at baseline was indirectly associated with greater 7–12-month drinking intensity through higher coping motives at 6 months. Negative emotionality was not related to change in coping motives over the assessment period and change in coping motives was not related to 7–12-month drinking intensity.

Conclusions

This analysis provides evidence for the predictive validity of the ANA negative emotionality domain for coping motives and drinking intensity among treatment seekers who experienced a lapse to drinking. Coping motives may be an important target in AUD treatment among those high in negative emotionality.
A water drop-shaped slingshot in plants: geometry and mechanics in the explosive seed dispersal of Orixa japonica (Rutaceae)
Authors: Huang Lan-Jie , Fu Wen-Long
Published: February 2021

Background and Aims

In angiosperms, many species disperse their seeds autonomously by rapid movement of the pericarp. The fruits of these species often have long rod- or long plate-shaped pericarps, which are suitable for ejecting seeds during fruit dehiscence by bending or coiling. However, here we show that fruit with a completely different shape can also rely on pericarp movement to disperse seeds explosively, as in Orixa japonica.

Methods

Fruit morphology was observed by hard tissue sectioning, scanning electron microscopy and micro-computed tomography, and the seed dispersal process was analysed using a high-speed camera. Comparisons were made of the geometric characteristics of pericarps before and after fruit dehiscence, and the mechanical process of pericarp movement was simulated with the aid of the finite element model.

Key Results

During fruit dehydration, the water drop-shaped endocarp of O. japonica with sandwich structure produced two-way bending deformation and cracking, and its width increased more than three-fold before opening. Meanwhile the same shaped exocarp with uniform structure could only produce small passive deformation under relatively large external forces. The endocarp forced the exocarp to open by hygroscopic movement before seed launching, and the exocarp provided the acceleration for seed launching through a reaction force.

Conclusions

Two layers of water drop-shaped pericarp in O. japonica form a structure similar to a slingshot, which launches the seed at high speed during fruit dehiscence. The results suggest that plants with explosive seed dispersal appear to have a wide variety of fruit morphology, and through a combination of different external shapes and internal structures, they are able to move rapidly using many sophisticated mechanisms.
Per-sample standardization and asymmetric winsorization lead to accurate clustering of RNA-seq expression profiles
Authors: Risso Davide , Pagnotta Stefano Maria
Published: February 2021

Motivation

Data transformations are an important step in the analysis of RNA-seq data. Nonetheless, the impact of transformation on the outcome of unsupervised clustering procedures is still unclear.

Results

Here, we present an Asymmetric Winsorization per-Sample Transformation (AWST), which is robust to data perturbations and removes the need for selecting the most informative genes prior to sample clustering. Our procedure leads to robust and biologically meaningful clusters both in bulk and in single-cell applications.

Availability and implementation

The AWST method is available at https://github.com/drisso/awst. The code to reproduce the analyses is available at https://github.com/drisso/awst_analysis

Supplementary information

Supplementary data are available at Bioinformatics online.
Differentially conserved amino acid positions may reflect differences in SARS-CoV-2 and SARS-CoV behaviour
Authors: Bojkova Denisa , McGreig Jake E , McLaughlin Katie-May , Masterson Stuart G , Antczak Magdalena , Widera Marek , Krähling Verena , Ciesek Sandra , Wass Mark N , Michaelis Martin , Cinatl Jindrich
Published: February 2021

Motivation

SARS-CoV-2 is a novel coronavirus currently causing a pandemic. Here, we performed a combined in-silico and cell culture comparison of SARS-CoV-2 and the closely related SARS-CoV.

Results

Many amino acid positions are differentially conserved between SARS-CoV-2 and SARS-CoV, which reflects the discrepancies in virus behaviour, i.e. more effective human-to-human transmission of SARS-CoV-2 and higher mortality associated with SARS-CoV. Variations in the S protein (mediates virus entry) were associated with differences in its interaction with ACE2 (cellular S receptor) and sensitivity to TMPRSS2 (enables virus entry via S cleavage) inhibition. Anti-ACE2 antibodies more strongly inhibited SARS-CoV than SARS-CoV-2 infection, probably due to a stronger SARS-CoV-2 S-ACE2 affinity relative to SARS-CoV S. Moreover, SARS-CoV-2 and SARS-CoV displayed differences in cell tropism. Cellular ACE2 and TMPRSS2 levels did not indicate susceptibility to SARS-CoV-2. In conclusion, we identified genomic variation between SARS-CoV-2 and SARS-CoV that may reflect the differences in their clinical and biological behaviour.

Supplementary information

Supplementary data are available at Bioinformatics online.
Integrating intraspecific variation in species distribution models by quantifying niche differentiation
Authors: Zhang Sheng-Nan , Kubota Kôhei
Published: February 2021

Intraspecific variation provides insight into heterogeneous demography and adaptive history across distribution ranges of organisms. Most species distribution models assume that species respond to the environment as a single undifferentiated entity across their entire distribution. However, populations occupying different niches might differ in their ability to cope with climate change. Here, we assessed potential climatic niche differentiation at the species and subspecies levels and identified the palaeoclimatic range of three cold-adapted, low-dispersal beetle species: Carabus irregularis, Platycerus albisomni and Platycerus takakuwai. Our results showed that: (1) MaxEnt models incorporating information derived from intraspecific variation outperformed the species-level models; (2) tests of niche similarity revealed niche conservatism in most subspecies, except for two subspecies of C. irregularis, C. i. irregularis and C. i. bucephalus; and (3) historical predictions suggested substantial shifts within species ranges, with multiple glacial refugia during the Last Glacial Maximum. In conclusion, we recommend closer examination of intraspecific variation when predicting species distributions, in order to obtain more accurate generalizations regarding range shifts under climate change.
Signatures of north-eastern expansion and multiple refugia: genomic phylogeography of the Pine Barrens tree frog,Hyla andersonii(Anura: Hylidae)
Authors: Warwick Alexa R , Barrow Lisa N , Smith Megan L , Means D Bruce , Lemmon Alan R , Lemmon Emily Moriarty
Published: February 2021

Range fragmentation poses challenges for species persistence over time and can be caused by both historical and contemporary processes. We combined genomic data, phylogeographical model testing and palaeoclimatic niche modelling to infer the evolutionary history of the Pine Barrens tree frog (Hyla andersonii), a seepage bog specialist, in eastern North America to gain a better understanding of the historical context of its fragmented distribution. We sampled H. andersonii populations across the three disjunct regions of the species range: Alabama/Florida (AF), the Carolinas (CL) and New Jersey (NJ). Phylogenetic relationships within H. andersonii were consistent between the nuclear species tree and mitochondrial analyses, indicating divergence between AF and CL/NJ (Atlantic clade) ~0.9 Mya and divergence of the NJ clade ~0.15 Mya. Several predictions of north-eastern expansion along the Atlantic coast were supported by phylogeographical analyses. Model testing using genome-wide single nucleotide polymorphism data and species distribution models both provided evidence for multiple disjunct refugia. This comprehensive phylogeographical study of H. andersonii demonstrates a long history of range fragmentation within an endemic coastal plain species and highlights the influence of historical climate change on the current distribution of species and their genetic diversity.
Interactions between the introduced European honey bee and native bees in urban areas varies by year, habitat type and native bee guild
Authors: Prendergast Kit S , Dixon Kingsley W , Bateman Philip W
Published: February 2021

European honey bees have been introduced across the globe and may compete with native bees for floral resources. Compounding effects of urbanization and introduced species on native bees are, however, unclear. Here, we investigated how honey bee abundance and foraging patterns related to those of native bee abundance and diversity in residential gardens and native vegetation remnants for 2 years in urbanized areas of the Southwest Australian biodiversity hotspot and assessed how niche overlap influenced these relationships. Honey bees did not overtly suppress native bee abundance; however, complex relationships emerged when analysing these relationships according to body size, time of day and floral resource levels. Native bee richness was positively correlated with overall honeybee abundance in the first year, but negatively correlated in the second year, and varied with body size. Native bees that had higher resource overlap with honey bees were negatively associated with honey bee abundance, and resource overlap between honey bees and native bees was higher in residential gardens. Relationships with honey bees varied between native bee taxa, reflecting adaptations to different flora, plus specialization. Thus, competition with introduced bees varies by species and location, mediated by dietary breadth and overlap and by other life-history traits of individual bee species.
Structure-preserving integrated analysis for risk stratification with application to cancer staging
Authors: Wang Tianjie , Chen Rui , Liu Wenshuo , Yu Menggang
Published: February 2021

To provide appropriate and practical level of health care, it is critical to group patients into relatively few strata that have distinct prognosis. Such grouping or stratification is typically based on well-established risk factors and clinical outcomes. A well-known example is the American Joint Committee on Cancer staging for cancer that uses tumor size, node involvement, and metastasis status. We consider a statistical method for such grouping based on individual patient data from multiple studies. The method encourages a common grouping structure as a basis for borrowing information, but acknowledges data heterogeneity including unbalanced data structures across multiple studies. We build on the “lasso-tree” method that is more versatile than the well-known classification and regression tree method in generating possible grouping patterns. In addition, the parametrization of the lasso-tree method makes it very natural to incorporate the underlying order information in the risk factors. In this article, we also strengthen the lasso-tree method by establishing its theoretical properties for which Lin and others (2013. Lasso tree for cancer staging with survival data. Biostatistics 14, 327–339) did not pursue. We evaluate our method in extensive simulation studies and an analysis of multiple breast cancer data sets.
Association between Quantitative MR Markers of Cortical Evolving Organization and Gene Expression during Human Prenatal Brain Development
Authors: Vasung Lana , Zhao Chenying , Barkovich Matthew , Rollins Caitlin K , Zhang Jennings , Lepage Claude , Corcoran Teddy , Velasco-Annis Clemente , Yun Hyuk Jin , Im Kiho , Warfield Simon Keith , Evans Alan Charles , Huang Hao , Gholipour Ali , Grant Patricia Ellen
Published: February 2021

The relationship between structural changes of the cerebral cortex revealed by Magnetic Resonance Imaging (MRI) and gene expression in the human fetal brain has not been explored. In this study, we aimed to test the hypothesis that relative regional thickness (a measure of cortical evolving organization) of fetal cortical compartments (cortical plate [CP] and subplate [SP]) is associated with expression levels of genes with known cortical phenotype. Mean regional SP/CP thickness ratios across age measured on in utero MRI of 25 healthy fetuses (20–33 gestational weeks [GWs]) were correlated with publicly available regional gene expression levels (23–24 GW fetuses). Larger SP/CP thickness ratios (more pronounced cortical evolving organization) was found in perisylvian regions. Furthermore, we found a significant association between SP/CP thickness ratio and expression levels of the FLNA gene (mutated in periventricular heterotopia, congenital heart disease, and vascular malformations). Further work is needed to identify early MRI biomarkers of gene expression that lead to abnormal cortical development.
A Phase 3, Randomized, Double-Blind Study Comparing Tedizolid Phosphate and Linezolid for Treatment of Ventilated Gram-Positive Hospital-Acquired or Ventilator-Associated Bacterial Pneumonia
Authors: Wunderink Richard G , Roquilly Antoine , Croce Martin , Rodriguez Gonzalez Daniel , Fujimi Satoshi , Butterton Joan R , Broyde Natasha , Popejoy Myra W , Kim Jason Y , De Anda Carisa
Published: February 2021

Background

Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP) are associated with high mortality rates. We evaluated the efficacy and safety of tedizolid (administered as tedizolid phosphate) for treatment of gram-positive ventilated HABP/VABP.

Methods

In this randomized, noninferiority, double-blind, double-dummy, global phase 3 trial, patients were randomized 1:1 to receive intravenous tedizolid phosphate 200 mg once daily for 7 days or intravenous linezolid 600 mg every 12 hours for 10 days. Treatment was 14 days in patients with concurrent gram-positive bacteremia. The primary efficacy end points were day 28 all-cause mortality (ACM; noninferiority margin, 10%) and investigator-assessed clinical response at test of cure (TOC; noninferiority margin, 12.5%) in the intention-to-treat population.

Results

Overall, 726 patients were randomized (tedizolid, n = 366; linezolid, n = 360). Baseline characteristics, including incidence of methicillin-resistant Staphylococcus aureus (31.3% overall), were well balanced. Tedizolid was noninferior to linezolid for day 28 ACM rate: 28.1% and 26.4%, respectively (difference, –1.8%; 95% confidence interval [CI]: –8.2 to 4.7). Noninferiority of tedizolid was not demonstrated for investigator-assessed clinical cure at TOC (tedizolid, 56.3% vs linezolid, 63.9%; difference, –7.6%; 97.5% CI: –15.7 to 0.5). In post hoc analyses, no single factor accounted for the difference in clinical response between treatment groups. Drug-related adverse events occurred in 8.1% and 11.9% of patients who received tedizolid and linezolid, respectively.

Conclusions

Tedizolid was noninferior to linezolid for day 28 ACM in the treatment of gram-positive ventilated HABP/VABP. Noninferiority of tedizolid for investigator-assessed clinical response at TOC was not demonstrated. Both drugs were well tolerated.

Clinical Trials Registration

NCT02019420.
Impact of Severe Acute Respiratory Syndrome Coronavirus 2 Infection on Pregnancy Outcomes: A Population-based Study
Authors: Crovetto Francesca , Crispi Fàtima , Llurba Elisa , Pascal Rosalia , Larroya Marta , Trilla Cristina , Camacho Marta , Medina Carmen , Dobaño Carlota , Gomez-Roig Maria Dolores , Figueras Francesc , Gratacos Eduard ,   KidsCorona Pregnancy COVID-19 Group, Arranz Angela , Cantallops Martí , Casas Irene , Tortajada Marta , Cahuana Àlex , Muro Patricia , Valdés-Bango Marta , Boada David , Mundo Anna , Lopez Marta , Goncé Anna , Santano Rebeca , Mercade Imma , Casals Elena , Marcos Maria Ángeles , Yague Jordi , Renau Montserrat Izquierdo , Fumado Vicky , Muñoz-Almagro Carmen , Jou Cristina , García-Osuna Alvaro , Mora Josefina
Published: February 2021

Background

We performed a population-based study to describe the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on pregnancy outcomes.

Methods

This prospective, population-based study included pregnant women who consecutively presented at first/second trimester visits or at delivery at 3 hospitals in Barcelona, Spain. SARS-CoV-2 antibodies (immunoglobulin [Ig] G and IgM/IgA) were measured in all participants, and nasopharyngeal real-time polymerase chain reaction (RT-PCR) was performed at delivery. The primary outcome was a composite of pregnancy complications in SARS-CoV-2–positive vs negative women that included miscarriage, preeclampsia, preterm delivery, perinatal death, small-for-gestational-age newborn, or neonatal admission. Secondary outcomes were components of the primary outcome plus abnormal fetal growth, malformation, or intrapartum fetal distress. Outcomes were also compared between positive symptomatic and positive asymptomatic SARS-CoV-2 women.

Results

Of 2225 pregnant women, 317 (14.2%) were positive for SARS-CoV-2 antibodies (n = 314, 99.1%) and/or RT-PCR (n = 36, 11.4%). Among positive women, 217 (68.5%) were asymptomatic, 93 (29.3%) had mild coronavirus disease 2019 (COVID-19), and 7 (2.2%) had pneumonia, of whom 3 required intensive care unit admission. In women with and without SARS-CoV-2 infection, the primary outcome occurred in 43 (13.6%) and 268 (14%), respectively (risk difference, –0.4%; 95% confidence interval, –4.1% to 4.1). Compared with noninfected women, those with symptomatic COVID-19 had increased rates of preterm delivery (7.2% vs 16.9%, P = .003) and intrapartum fetal distress (9.1% vs 19.2%, P = .004), while asymptomatic women had rates that were similar to those of noninfected cases. Among 143 fetuses from infected mothers, none had anti–SARS-CoV-2 IgM/IgA in cord blood.

Conclusions

The overall rate of pregnancy complications in women with SARS-CoV-2 infection was similar to that of noninfected women. However, symptomatic COVID-19 was associated with modest increases in preterm delivery and intrapartum fetal distress.