bluuebunny/crossref_metadata_2025 huggingface dataset:
Interplay between degree and Boolean rules in the stability of Boolean networks
Authors: Min Byungjoon
Published: September 2020

Empirical evidence has revealed that biological regulatory systems are controlled by high-level coordination between topology and Boolean rules. In this study, we look at the joint effects of degree and Boolean functions on the stability of Boolean networks. To elucidate these effects, we focus on (1) the correlation between the sensitivity of Boolean variables and the degree and (2) the coupling between canalizing inputs and degree. We find that negatively correlated sensitivity with respect to local degree enhances the stability of Boolean networks against external perturbations. We also demonstrate that the effects of canalizing inputs can be amplified when they coordinate with high in-degree nodes. Numerical simulations confirm the accuracy of our analytical predictions at both the node and network levels.
Impact of dopant-induced optoelectronic tails on open-circuit voltage in arsenic-doped Cd(Se)Te solar cells
Authors: Moseley John , Grover Sachit , Lu Dingyuan , Xiong Gang , Guthrey Harvey L. , Al-Jassim Mowafak M. , Metzger Wyatt K.
Published: September 2020

Fluctuations refer to inhomogeneity in the distribution of donors and acceptors at the nanometer scale and occur in many compound solar cell materials such as Cu(In,Ga)Se2, Cu2ZnSn(S,Se)4, and CdSexTe1−x. In this work, numerical simulations show that these fluctuations produce not only electrostatic potential variation, but also, local changes in the carrier density and effective bandgap. For a CdSexTe1−x absorber doped with arsenic, simulations and cathodoluminescence data within single grains demonstrate how donor and acceptor densities—consistent with capacitance-voltage and secondary-ion mass-spectrometry data—produce tails in photoluminescence, quantum efficiency, and absorption measurements. Using multiple theoretical approaches, we demonstrate that the fluctuations can hinder expected performance gains from increased carrier density, and we describe the significant open-circuit voltage deficit observed in the CdSexTe1−x:As solar technology. Our results demonstrate that it is critical to characterize and reduce carrier compensation to realize a higher efficiency.
Shubnikov–de Haas oscillations and Rashba splitting in Bi2Te3 epitaxial film
Authors: Holgado D. P. A. , Bolaños K. , de Castro S. , Monteiro H. S. A. , Pena F. S. , Okazaki A. K. , Fornari C. I. , Rappl P. H. O. , Abramof E. , Soares D. A. W. , Peres M. L.
Published: September 2020

This work presents the results of magnetotransport measurements performed on a 156 nm-thick Bi2Te3 epitaxial film in the temperature range of 1.9–300 K, showing Shubnikov–de Haas oscillations for temperatures below 50 K. A detailed analysis of oscillations as a function of temperature provides the main transport parameters, including the Landé g-factor and cyclotronic masses. A systematic analysis of fast Fourier transform, performed on the oscillations, indicates that the origin of the oscillation pattern is not related to the topological surface states but from the Rashba splitting of the Bi2Te3 Fermi surface.
Lateral and vertical growth of Mg-doped GaN on trench-patterned GaN films
Authors: Su Po-Yi , Liu Hanxiao , Yang Chen , Fu Kai , Fu Houqiang , Zhao Yuji , Ponce Fernando A.
Published: September 2020

Growth of Mg-doped GaN on trench-patterned GaN films consists of competing lateral and vertical growth fronts that result in regions with different electronic properties. Under typical growth conditions, lateral growth from the trench sidewall occurs at a faster rate than vertical growth from the trench base. When the trench width is sufficiently narrow, the growth fronts from opposite sidewalls coalesce and lead to eventual planarization of the top surface. Secondary electron imaging and cathodoluminescence mapping are used to correlate the morphology and the optical properties of regions resulting from lateral and vertical growth. For our growth conditions, the lateral-to-vertical growth rate ratio is found to be about 2.
A stand-alone magnetic guide for producing tuneable radical beams
Authors: Miossec Chloé , Wu Lok Yiu , Bertier Paul , Hejduk Michal , Toscano Jutta , Heazlewood Brianna R.
Published: September 2020

Radicals are prevalent in gas-phase environments such as the atmosphere, combustion systems, and the interstellar medium. To understand the properties of the processes occurring in these environments, it is helpful to study radical reaction systems in isolation—thereby avoiding competing reactions from impurities. There are very few methods for generating a pure beam of gas-phase radicals, and those that do exist involve complex setups. Here, we provide a straightforward and versatile solution. A magnetic radical filter (MRF), composed of four Halbach arrays and two skimming blades, can generate a beam of velocity-selected low-field-seeking hydrogen atoms. As there is no line-of-sight through the device, all species that are unaffected by the magnetic fields are physically blocked; only the target radicals are successfully guided around the skimming blades. The positions of the arrays and blades can be adjusted, enabling the velocity distribution of the beam (and even the target radical species) to be modified. The MRF is employed as a stand-alone device—filtering radicals directly from the source. Our findings open up the prospect of studying a range of radical reaction systems with a high degree of control over the properties of the radical reactants.
Understanding how water models affect the anomalous pressure dependence of their diffusion coefficients
Authors: Teng Xiaojing , Liu Bailang , Ichiye Toshiko
Published: September 2020

The self-diffusion coefficient of water shows an anomalous increase with increasing hydrostatic pressure up to a broad maximum (PmD) near 1 kbar at 298 K, which has been attributed to pressure effects on the tetrahedral hydrogen bond network of water. Moreover, the ability of a water model to reproduce anomalous properties of water is a signature that it is reproducing the network. Here, water was simulated between 1 bar and 5 kbar using three water models, two four-site (with all charges in the molecular plane) and one single-site multipole (which accounts for out-of-molecular plane charge), that have reasonable pressure–temperature properties. For these three models, the diffusion coefficients display a maximum in the pressure dependence and the radial distribution functions show good agreement with the limited experimental structural data at high pressure that are available. In addition, a variety of properties associated with the network are examined, including hydrogen bond lifetimes and occupancies, three-body angle distributions, and tetrahedral order parameters. Results suggest that the initial increasing diffusion with pressure is because hydrogen bonds are distorted and thus weakened by pressure, but above PmD, the hydrogen bonds are weakened to the point it behaves more like a normal liquid. In other words, the PmD may be a measure of the angular strength of hydrogen bonds. In addition, since the four-site models over-predict the values of PmD while the multipole model under-predicts it, out-of-plane charge may improve four-site models.
Transferable interactions of Li+ and Mg2+ ions in polarizable models
Authors: Wineman-Fisher Vered , Delgado Julián Meléndez , Nagy Péter R. , Jakobsson Eric , Pandit Sagar A. , Varma Sameer
Published: September 2020

Therapeutic implications of Li+, in many cases, stem from its ability to inhibit certain Mg2+-dependent enzymes, where it interacts with or substitutes for Mg2+. The underlying details of its action are, however, unknown. Molecular simulations can provide insights, but their reliability depends on how well they describe relative interactions of Li+ and Mg2+ with water and other biochemical groups. Here, we explore, benchmark, and recommend improvements to two simulation approaches: the one that employs an all-atom polarizable molecular mechanics (MM) model and the other that uses a hybrid quantum and MM implementation of the quasi-chemical theory (QCT). The strength of the former is that it describes thermal motions explicitly and that of the latter is that it derives local contributions from electron densities. Reference data are taken from the experiment, and also obtained systematically from CCSD(T) theory, followed by a benchmarked vdW-inclusive density functional theory. We find that the QCT model predicts relative hydration energies and structures in agreement with the experiment and without the need for additional parameterization. This implies that accurate descriptions of local interactions are essential. Consistent with this observation, recalibration of local interactions in the MM model, which reduces errors from 10.0 kcal/mol to 1.4 kcal/mol, also fixes aqueous phase properties. Finally, we show that ion–ligand transferability errors in the MM model can be reduced significantly from 10.3 kcal/mol to 1.2 kcal/mol by correcting the ligand’s polarization term and by introducing Lennard-Jones cross-terms. In general, this work sets up systematic approaches to evaluate and improve molecular models of ions binding to proteins.
Benchmarking Australian sheep parasite control practices: a national online survey
Authors: Colvin A. F. , Reeve I. , Peachey B. , Walkden-Brown S. W.
Published: September 2020

Context
The third Australian national survey on control practices for internal and external parasites of sheep, following similar surveys in 2003 and 2011.

Aims
To document current parasite control practices and attitudes, measure change and to provide a benchmark against which to assess future practices and attitudes.

Methods
An online survey emailed to 6460 sheep producers, with a paper version supplied on request. A follow up short survey was conducted to assess non-response bias. Analysis by region and key sheep enterprise.

Key results
There were 354 and 250 useable responses to the main and short surveys respectively. Mean reported rainfall of 407 mm in 2018 was 27% lower than the average for respondents and >200 mm lower than mean reported rainfall in the previous surveys. The top three methods for worm control over the past 5 years were preventative treatments (74%), preparing clean pastures by spelling paddocks (62%) and treatment on the basis of faecal worm egg count (WEC, 54%). The proportion of respondents using WEC monitoring in 2018 was 40.4%, with a mean frequency of 3.1/year, and this was unaffected by sheep class. The frequency of anthelmintic treatment for ewes and lambs and weaners was 2.1/year. Of the respondents, 36.7% had performed an anthelmintic resistance test in the previous 5 years. The most popular flystrike control methods were timing of crutching (76.4%), preventative chemical treatment (75.9%), timing of shearing (63.1%), mulesing (46.8%) and genetic selection (46.4%). Pain relief was widely used for mulesing ewes (86.6%) and wethers (90.9%). Only 17.3% used Australian Sheep Breeding Values for traits in rams. Most respondents reported ‘evidence of lice’ in the past 5 years (55.8%) and had treated for lice off shears (50.1%), short wool (16.6%) or long wool (6.6%), with only 26.7% having not treated at all in the period. Web-based sources of information on parasite control have become increasingly important.

Conclusions
Notable changes since the earlier surveys were high rates of pain relief when mulesing, an increase in the use of Australian Sheep Breeding Values for parasite-related traits, an increase in WEC monitoring since 2011 and an increased use of web-based resources.

Implications
Parasite control remains important for sheep producers and continues to evolve with new drugs and approaches. The surveys highlight the effectiveness of extension networks and identify where more attention is required.
Homeostatic mechanisms regulate distinct aspects of cortical circuit dynamics
Authors: Wu Yue Kris , Hengen Keith B. , Turrigiano Gina G. , Gjorgjieva Julijana
Published: September 2020

Significance

Despite decades of intense studies on homeostasis, network properties undergoing homeostatic regulation remain elusive. Furthermore, whether diverse forms of homeostatic plasticity are simply redundant or serve distinct functions is unclear. Here, our data show that functional correlations are subject to homeostatic regulation, both in terms of average amplitude and their structure. A computational model demonstrates that synaptic scaling is essential for the restoration of correlations and network structure, whereas intrinsic plasticity is crucial for the recovery of firing rates after perturbations, suggesting that synaptic scaling and intrinsic plasticity distinctly contribute to homeostatic regulation.
Tunable layered composites based on magnetoactive elastomers and piezopolymer for sensors and energy harvesting devices
Authors: Makarova L A , Alekhina Yu A , Isaev D A , Khairullin M F , Perov N S
Published: September 2020

The novel layered structures comprising piezoelectric polymer and magnetoactive elastomer (MAE) were developed and investigated. The influence of iron particles content in the elastomeric layer, its thickness and Young’s modulus of silicone on the multiferroic properties of the structures were analyzed. The investigation included the experimental and numerical characterization of the magnetoelectric effect. The giant values of bending deformations of MAEs in the external gradient magnetic field led to giant values of induced voltage (up to nearly 650 mV) in the composite. The displacement of ferromagnetic particles inside the elastomeric matrix under gradient magnetic field became the main basis for numerical modelling. The molecular dynamic method, ‘virtual springs’ method and Verlet algorithm were used to obtain the results of the numerical experiment. The energy transformation and magnetic field response in the novel composite allow it to be used in sensors and energy-harvesting devices.
Full-space polarization-regulated lightwave steering via single-layer metasurfaces
Authors: Yang Hui , Xie Zhenwei , Zhou Zhangyu , Yuan Xiaocong
Published: September 2020

Metasurfaces can offer unprecedented superiority in manipulating the wavefront of electromagnetic waves and have attracted much attention around the world. However, to date, most of the metasurfaces reported only operate in either transmission or reflection space, leaving half of the space unexplored. Here we propose a general scheme for designing full-space polarization-regulated wavefront steering via single-layer metasurfaces. Specifically, the designed metasurface can change its functionality and working space (from transmission space to reflection space and vice versa) by varying the incident polarization. For a proof of concept, we demonstrate numerically two full-space polarization-regulated metasurfaces. As incident x-polarized light changes to y-polarized light, the functionality of two devices is switched from a reflected metalens and an Airy bean generator to a transmitted focusing vortex generator and a metalens, respectively. Here the design strategy is generalized and can be adapted to design other polarization-regulated meta-devices at other wavelengths. In regard to wavefront control, these results significantly expand the scope of metasurfaces, providing new possibilities to develop full-space multifunctional meta-devices.
The luminosity constraint in the era of precision solar physics
Authors: Vescovi Diego , Mascaretti Carlo , Vissani Francesco , Piersanti Luciano , Straniero Oscar
Published: September 2020

The luminosity constraint is a very precise relationship linking the power released by the Sun as photons and the solar neutrino fluxes. Such a relation, which is a direct consequence of the physical processes controlling the production and the transport of energy in the solar interior, is of great importance for the studies of solar neutrinos and has a special role for the search of neutrinos from the CNO cycle, whose first detection with a 5σ significance has been recently announced by the Borexino collaboration. Here we revise the luminosity constraint, discussing and validating its underlying hypotheses, in the light of latest solar neutrino and luminosity measurements. We generalize the current formulation of the luminosity constraint relation so that it can be easily used in future analysis of solar neutrino data, and we provide a specific application showing the link between CNO and pp neutrino fluxes.
Lifetime measurements in 104Pd
Authors: Majumder C , Sharma H P , Chakraborty S , Tiwary S S , Singh R P , Muralithar S , Bala Indu , Bhattacharjee S S , Garg R , Neelam  , Sharma A , Rao P V Madhusudhana
Published: September 2020

High spin states in 104Pd were populated via 94Zr(13C, 3nγ) fusion-evaporation reaction at a beam energy of 55 MeV. The Indian National Gamma Array was utilized to detect the de-exciting γ-rays. Lifetimes of states in the negative parity bands have been determined using the Doppler shift attenuation method. The present lifetime results suggest a moderate quadrupole deformation (β
2 ≈ 0.2) for the negative parity bands. The Woods–Saxon total Routhian surface calculations have also been carried out which predicted a similar deformation for these bands. In addition, lifetimes of states in the positive parity band have also been determined. Present results found in agreement with the earlier reported values of lifetimes and hence agreed with the antimagnetic rotational character of the band as interpreted earlier.
Multi-frequency-band deep CNN model for tool wear prediction
Authors: Duan Jian , Duan Jie , Zhou Hongdi , Zhan Xiaobin , Li Tianxiang , Shi Tielin
Published: September 2020

A reliable data-driven tool condition monitoring system is more and more promising for cutting down on machine downtime and economic losses. However, traditional methods are not able to address machining big data because of low model generalizability and laborious feature extraction by hand. In this paper, a novel deep learning model, named multi-frequency-band deep convolution neural network (MFB-DCNN), is proposed to handle machining big data and to monitor tool condition. First, samples are enlarged and a three-layer wavelet package decomposition is applied to obtain wavelet coefficients in different frequency bands. Then, the multi-frequency-band feature extraction structure based on a deep convolution neural network structure is introduced and utilized for sensitive feature extraction from these coefficients. The extracted features are fed into full connection layers to predict tool wear conditions. After this, milling experiments are conducted for signal acquisition and model construction. A series of hyperparameter selection experiments is designed for optimization of the proposed MFB-DCNN model. Finally, the prediction performance of typical models is evaluated and compared with that of the proposed model. The results show that the proposed model has outstanding generalizability and higher prediction performance, and a well designed structure can remedy the absence of complicated feature engineering.
Measurement and evaluation of soft soil strength development during freeze-thaw process based on electromechanical impedance technique
Authors: Zhang Chuan , Yan Qixiang , Wang Xianfeng , Panda Guru Prasad , Vipulanandan Cumaraswamy , Song Gangbing
Published: September 2020

In-situ monitoring of soft soil strength development is of great significance in artificial ground freezing (AGF) projects. It can not only help engineers estimate the soil freeze-thaw status, but also provide useful data for predicting and controlling the concurrent adverse effects which may cause serious engineering accidents. As a useful nondestructive testing method, the electromechanical impedance (EMI) method has already been extensively employed in a wide range of monitoring applications. In this research, the applicability of the EMI method was extended to monitoring the soil freeze-thaw process and the strength development for the first time. Through the experimental research, a lead zirconate titanate transducer was adopted to measure the changes in the conductance signature during the freeze-thaw process. Furthermore, the lateral and vertical shifts of the resonance peak in the electromechanical spectra and three statistic indices were employed as indicators for the quantitative evaluation of the unconfined compressive strength of the soil specimen. The experimental results verified the effectiveness and reliability of the proposed method in monitoring the soil compressive strength development. This method will have broad prospects in in-situ monitoring of the soil strength development in AGF projects.
Unusual effects of nanowire-nanowire junctions on the persistent photoconductivity in SnO2 nanowire network devices
Authors: Costa I M , de Araújo E P , Arantes A N , Zaghete M A , Chiquito A J
Published: September 2020

The persistent photoconductivity (PPC) effect is a commonly observed behavior in SnO2 nanostructures. Here we described and studied this effect through a comparative study, based on measurements of electronic transport using network as well as single devices built from SnO2 nanowires under different experimental conditions. At room temperature, the PPC effect was observed to be more accentuated in single nanowire devices. It was found that nanowire-nanowire junctions play a fundamental role in the device behavior: the decay time of nanowire network (τ = 52 s) is about three orders of magnitude lower than those of single nanowire (τ = 4.57 × 104 s). Additionally, it was confirmed that the PPC effect was directly related to the amount of oxygen present in the environment and it is destroyed with increasing temperature. Furthermore, the PPC effect was interpreted based on the surface effect that depends on the capture/emission of electrons by the surface states.
A first-principles study of Janus monolayer TiSSe and VSSe as anode materials in alkali metal ion batteries
Authors: Xiong Fen , Chen Yue
Published: September 2020

Anode materials play an important role in the performance of rechargeable batteries and have been attracting much research interest. In this work, we have investigated the electrochemical properties of two-dimensional (2D) Janus MSSe (M = Ti or V) for potential applications as anode materials in alkali metal ion batteries from density functional theory (DFT), following the recent successful synthesis of 2D Janus MoSSe. Our DFT calculations suggest that 2D Janus TiSSe and VSSe are stable in the 1T phase and 1H phase, respectively. It is found that alkali metal atoms X (X = Li, Na or K) can be stably adsorbed on the surfaces of Janus MSSe, and have low diffusion energy barriers. Additionally, small volume changes are observed in Janus MSSe after the adsorption of alkali metal atoms. It is predicted that the MSSe-2X systems have low open circuit voltages and high capacities. Our results suggest that 2D Janus TiSSe and VSSe are potential anode materials for alkali metal ion batteries.
Hard template synthesis of 2D porous Co3O4 nanosheets with graphene oxide for H2O2 sensing
Authors: Zhang Xinmeng , Zhao Yuanxiao , Huang Shuohan , Wu Yuanting , Mao Zixuan , Wang Xiufeng
Published: September 2020

In this work, we used graphene oxide (GO) as a template that was removed by calcination to finally successfully prepare Co3O4 with 2D porous nanostructure. The results show that 2D porous structure Co3O4 nanosheets were only prepared at pH = 2. After electrochemical tests, the as-prepared Co3O4 nanosheets showed electrochemical properties that are highly suitable for H2O2 detection, such as high current response, short response time (less than 3 s), wide linear range (0.388–44.156 mM), low limit of detection (2.33 μM) and high sensitivity (0.0891 mA mM−1 cm−2). These excellent properties are mainly due to GO, as a 2D template, which connects Co3O4 nanoparticles to each other on a 2D plane, preventing the agglomeration of Co3O4 nanoparticles. The abundant pores between Co3O4 nanoparticles can greatly increase the reaction between the nanoparticles and H2O2 molecules.
SnSe2 realizes soliton rain and harmonic soliton molecules in erbium-doped fiber lasers
Authors: Luo Wenfeng , Liu Xiaoyu , Li Xiaohui , Lv Shuyuan , Xu Wenxiong , Wang Lu , Shi Zhaojiang , Zhang Chenxi
Published: September 2020

Two-dimensional layered metal chalcogenides (LMCs) are widely used in battery anode materials, energy conversion, and semiconductor devices, because of their high energy storage characteristics, high thermoelectric characteristics, and large electron mobility. SnSe2 as a kind of LMC has strong nonlinear optical characteristics. However, its research on dissipative system dynamics as a saturable absorber has not been studied. In this work, we obtained SnSe2 nanosheets using lithium ion intercalation and we reported a passively mode-locked fiber laser with SnSe2 as a saturable absorber to achieve the dissipative soliton in a dissipative system. Due to the high third-order nonlinearity of SnSe2, the evolution of square wave pulses from 2 to 16 ns was obtained in a fiber ring cavity. Through adjusting the polarization state, the evolution phenomenon of soliton rain, the soliton rain phenomenon with a spectrum of dual-wavelengths, and a bound state harmonic phenomenon with a frequency of 313 MHz were obtained. Therefore, the strong nonlinear fiber laser based on SnSe2 provides a good platform for study the pulsation, explosion, rainfall and other phenomena.
Advances in modelling gold nanoparticle radiosensitization using new Geant4-DNA physics models
Authors: Engels Elette , Bakr Samer , Bolst David , Sakata Dousatsu , Li Nan , Lazarakis Peter , McMahon Stephen J , Ivanchenko Vladimir , Rosenfeld Anatoly B , Incerti Sébastien , Kyriakou Ioanna , Emfietzoglou Dimitris , Lerch Michael L F , Tehei Moeava , Corde Stéphanie , Guatelli Susanna
Published: September 2020

Gold nanoparticles have demonstrated significant radiosensitization of cancer treatment with x-ray radiotherapy. To understand the mechanisms at the basis of nanoparticle radiosensitization, Monte Carlo simulations are used to investigate the dose enhancement, given a certain nanoparticle concentration and distribution in the biological medium. Earlier studies have ordinarily used condensed history physics models to predict nanoscale dose enhancement with nanoparticles. This study uses Geant4-DNA complemented with novel track structure physics models to accurately describe electron interactions in gold and to calculate the dose surrounding gold nanoparticle structures at nanoscale level. The computed dose in silico due to a clinical kilovoltage beam and the presence of gold nanoparticles was related to in vitro brain cancer cell survival using the local effect model. The comparison of the simulation results with radiobiological experimental measurements shows that Geant4-DNA and local effect model can be used to predict cell survival in silico in the case of x-ray kilovoltage beams.
Physics and technology of magnetron sputtering discharges
Authors: Gudmundsson J T
Published: September 2020

Magnetron sputtering deposition has become the most widely used technique for deposition of both metallic and compound thin films and is utilized in numerous industrial applications. There has been a continuous development of the magnetron sputtering technology to improve target utilization, increase ionization of the sputtered species, increase deposition rates, and to minimize electrical instabilities such as arcs, as well as to reduce operating cost. The development from the direct current (dc) diode sputter tool to the magnetron sputtering discharge is discussed as well as the various magnetron sputtering discharge configurations. The magnetron sputtering discharge is either operated as a dc or radio frequency discharge, or it is driven by some other periodic waveforms depending on the application. This includes reactive magnetron sputtering which exhibits hysteresis and is often operated with an asymmetric bipolar mid-frequency pulsed waveform. Due to target poisoning the reactive sputter process is inherently unstable and exhibits a strongly non-linear response to variations in operating parameters. Ionized physical vapor deposition was initially achieved by adding a secondary discharge between the cathode target and the substrate and later by applying high power pulses to the cathode target. An overview is given of the operating parameters, the discharge properties and the plasma parameters including particle densities, discharge current composition, electron and ion energy distributions, deposition rate, and ionized flux fraction. The discharge maintenance is discussed including the electron heating processes, the creation and role of secondary electrons and Ohmic heating, and the sputter processes. Furthermore, the role and appearance of instabilities in the discharge operation is discussed.
P-doping with beryllium of long-wavelength InAsSb
Authors: Svensson Stefan P , Sarney Wendy L , Beck William A , Liu Jinghe , Donetsky Dmitri , Suchalkin Sergey , Belenky Gregory , Kyrtsos Alexandros , Bellotti Enrico
Published: September 2020

The properties of low concentrations of Be as a p-dopant in InAsSb with a composition corresponding to absorption in the long wavelength infrared band were studied. Temperature- and magnetic field-dependent Hall effect data were analyzed with a multi-carrier model allowing extraction of the bulk hole concentration and mobility. The hole density exhibits a weak freeze-out with an activation energy of 3.2 meV. Density functional theory calculations indicate that Be favor the In sites as BeIn with an acceptor binding energy near the valence band maximum. The hole mobility increases monotonically as the temperature is lowered, showing an alloy scattering-limited value of about 1000 cm2 V−1 s−1 at 77 K and plateauing at around 3200 cm2 V−1 s−1 at 20 K. Temperature-dependent photoluminescence was measured up to 200 K and did not indicate any deleterious effects induced by the acceptors. A superlinear bandgap vs temperature behavior is tentatively interpreted as a band-filling effect, which is reduced with added concentrations of acceptors.
Recent progress on nanostructured bimetallic electrocatalysts for water splitting and electroreduction of carbon dioxide
Authors: Cui Can , Hu Xiaosong , Wen Liaoyong
Published: September 2020

The exploitation of renewable energy as well as the elimination of the harmful impact of excessive carbon emission are worldwide concerns for sustainable development of the ecological environment on earth. To address that, the technologies regarding energy conversion systems, such as water splitting and electroreduction of carbon dioxide, have attracted significant attention for a few decades. Yet, to date, the production of green fuels and/or high energy density chemicals like hydrogen, methane, and ethanol, are still suffering from many drawbacks including high energy consumption, low selectivity, and sluggish reaction rate. In this regard, nanostructured bimetallic materials that is capable of taking the full benefits of the coupling effects between different elements/components with structure modification in nanoscale are considered as a promising strategy for high-performance electrocatalysts. Herein, this review aims to outline the important progress of these nanostructured bimetallic electrocatalysts. It starts with the introduction of some important fundamental background knowledge about the reaction mechanism to understand how these reactions happen. Subsequently, we summarize the most recent progress regarding how the nanostructured bimetallic electrocatalysts manipulate the activity and selectivity of catalytic reactions in the order of bimetallic alloying effect, interface/substrate effect of bi-component electrocatalyst, and nanostructuring effect.
Metal-organic framework composites for energy conversion and storage
Authors: Wang Hang , Zhang Na , Li Shumin , Ke Qinfei , Li Zhengquan , Zhou Min
Published: September 2020

Metal-organic frameworks (MOFs) with orderly porous structure, large surface area, high electrochemical response and chemical tunability have been widely studied for energy conversion and storage. However, most reported MOFs still suffer from poor stability, insufficient conductivity, and low utilization of active sites. One strategy to circumvent these issues is to optimize MOFs via designing composites. Here, the design principle from the viewpoint of the intrinsic relationships among various components will be illuminated to acquire the synergistic effects, including two working modes: (1) MOFs with assistant components, (2) MOFs with other function components. This review introduces recent research progress of MOF-based composites with their typical applications in energy conversion (catalysis) and storage (supercapacitor and ion battery). Finally, the challenges and future prospects of MOF-based composites will be discussed in terms of maximizing composite properties.
Typical strategies to facilitate charge transfer for enhanced oxygen evolution reaction: Case studies on hematite
Authors: Liao Aizhen , He Huichao , Zhou Yong , Zou Zhigang
Published: September 2020

Hydrogen can be sustainably produced through photoelectrochemical (PEC) water splitting. The process of PEC water splitting is composed of two vital half-reactions: water oxidation to O2 on photoanode, and proton reduction to H2 on photocathode. Both in thermodynamics and kinetics, the oxidation of water on photoanode is much more challenging, because the formation of O2 involves the four-holes reaction process that is more difficult than the two-protons reduction. Accordingly, the oxidation of water into O2 is the rate-determining reaction for PEC water splitting, which is closely affected by the light harvesting, charge separation and transfer, as well as surface activity of photoanode. In principle, water oxidation is initiated by the photo-excited charge of photoanode. In this review, we took hematite photoanode as a typical example to illustrate the progress in modifying the charge separation and migration property of metal-oxide photoanodes for water oxidation. The typical strategies adopted to facilitate the charge transfer and separation of hematite photoanode were specifically summarized. In addition, the views designing and developing hematite photoanode with high-performance for water oxidation were presented. This review provides comprehensive information about the state-of-the-art progress of hematite-based photoanodes and forecast the developing directions of photoanode materials for solar water splitting.
Jumping archer fish exhibit multiple modes of fin–fin interaction
Authors: Mendelson Leah , Techet Alexandra H
Published: September 2020

Aquatic organisms jumping for aerial prey require high-performance propulsion, accurate aim, and trajectory control to succeed. Archer fish, capable of jumping up to twice their body length out of the water, address these considerations through multifaceted fin and body kinematics. In this study, we utilized 3D synthetic aperture particle image velocimetry to visualize the wakes of archer fish throughout the jumping process. We found that multiple modes of interaction between the anal and caudal fins occur during jump behaviors. Time-resolved volumetric measurements presented herein illustrate the hydrodynamics of each interaction mode in detail. Additionally, regardless of which fin uses and interactions were exhibited during a jump, we found similar relationships between the cumulative impulse of multiple propulsive vortices in the wake and the instantaneous ballistic momentum of the fish. Our results suggests that fin use may compensate for variations in individual kinematic events and in the aiming posture assumed prior to jumping and highlight how interactions between tailbeats and other fins help the archer fish reach necessary prey heights in a spatially- and visually-constrained environment. In the broader context of bioinspired propulsion, the archer fish exemplifies that multiple beneficial hydrodynamic interactions can be generated in a high-performance scenario using a single set of actuators.
Hazardous air pollutant exposure as a contributing factor to COVID-19 mortality in the United States
Authors: Petroni Michael , Hill Dustin , Younes Lylla , Barkman Liesl , Howard Sarah , Howell I Brielle , Mirowsky Jaime , Collins Mary B
Published: September 2020

To date, COVID-19 has claimed more than 100 000 American lives. Early inquiry suggests preexisting conditions are key risk factors contributing to COVID-19 mortality and air pollution exposure could exacerbate this relationship. Building on prior research linking deaths from respiratory viruses to air pollution exposures, we investigate how 2014 National Air Toxics Assessment hazardous air pollutants (HAPs) respiratory hazard quotient and respiratory hazard index are related to COVID-19 mortality. Our focus on HAPs builds upon the knowledge base linking poor air quality to COVID-19 mortality, since most (if not all) earlier studies only include criteria pollutants. Herein, we examine the relationship between HAP exposure and US-based COVID-19 mortality, while controlling for socioeconomic status, population health indicators, and exposure to PM2.5 and ozone. We fit county-level negative binomial mixed models, predicting COVID-19 mortality as a function of HAP respiratory toxicity levels and relevant covariates. We include models for combined exposure to HAPs, as well as for specific pollutants. We find that an increase in the respiratory hazard index is associated with a 9% increase in COVID-19 mortality. Although differing in magnitude, this association holds for individual HAPs acetaldehyde, and diesel PM. These findings help us to understand variation in US-based COVID-19 mortality rates, reinforce existing research linking air pollution to mortality, and emphasize the importance of regulatory efforts to limit air pollution exposure risk.
Extensive aircraft activity impacts subsistence areas: acoustic evidence from Arctic Alaska
Authors: Stinchcomb Taylor R , Brinkman Todd J , Betchkal Davyd
Published: September 2020

Aircraft activity is expanding across Arctic Alaska, potentially changing social-ecological systems. Arctic communities report that aircraft disturb wildlife and negatively influence harvest practices and experiences. Limited data have restricted knowledge about the extent of aircraft activity over traditional harvest areas. Our objective was to use soundscape monitoring methods to document aircraft overflights around the rural subsistence-based community of Nuiqsut to inform impact mitigation processes. This study provides the first quantitative estimates of aircraft activity in rural Arctic Alaska. We deployed 20 acoustic monitoring systems in summer 2016 along travel corridors used to harvest caribou (Rangifer tarandus). Sound recordings captured 7465 aircraft events during peak caribou harvest season. Aircraft activity reached a median of 12 overflights per day near human development, approximately six times greater than undeveloped areas. Aircraft noise decreased incrementally with distance from human development. Given that subsistence harvesters report that aircraft startle caribou and prefer to avoid aircraft themselves, this result implies that they will need to travel farther for a successful harvest, incurring higher costs of fuel, equipment, and effort. Such costs could be prohibitive for many harvesters. Our research demonstrates that acoustic data can aid in understanding how human-to-human interactions impact social-ecological dynamics in the Arctic.
Why escape is faster than expected
Authors: Attarchi Hassan , Bunimovich Leonid A
Published: September 2020

We consider chaotic (hyperbolic) dynamical systems which have a generating Markov partition. Then, open dynamical systems are built by making one element of a Markov partition a ‘hole’ through which orbits escape. We compare various estimates of the escape rate which correspond to a physical picture of leaking in the entire phase space. Moreover, we uncover a reason why the escape rate is faster than expected, which is the convexity of the function defining escape rate. Exact computations are present for the skewed tent map and Arnold’s cat map.
Application studies of organomineral fertilizer for restoration under the conditions of the Far North of disturbed illuvious-ferruginous podbur
Authors: Yu Aladin D , Sevostyanov S M , Deeva N F , Demin D V
Published: September 2020

The work is devoted to the use of organomineral fertilizer (OMF) based on food waste for sowing three mixtures of perennial cereals and the reclamation of an illuvial-ferruginous podbur in the Far North. Under the conditions of a model experiment, it was found that when OMF is introduced in fractions of 25 and 50%, the physicochemical properties of the soil improve. There is an increase in the green mass of plants relative to the control by 2.3 times. Adding 50% of the presented fertilizer leads to inhibition of cereals. The mass of plantings at this dose of fertilizer approaches the figures appearing in the experiment with 25% OMF. The presented organic-mineral fertilizer based on food waste can be used for the rehabilitation of disturbed soils of the illuvial-ferruginous podbur as fertilizer.
Polymeric stabilization of drilling drills with low content of solid phase
Authors: Lukanina Yu K , Belenko E V , Sakharov P A , Khvatov A V
Published: September 2020

This article is devoted to identifying the relationship between the structure-forming properties of polymer stabilizers of clay suspensions (drilling fluids) and the structure of their macromolecules based on thermodynamic representations of the stability of polymer-dispersed systems. New types of polymer-micellar gels combining high structural and pseudo-plastic properties and optimal surface-active characteristics characteristic of concentrated micellar systems of the “surfactant-solubilizate” type are presented.
Evaluation of organomineral fertilizer for restoration under the conditions of the Far North of disturbed illuvious-ferruginous podzol
Authors: Sevostyanov S M , Deeva N F , Yu Aladin D , Demin D V
Published: September 2020

The results of a model experiment on the use of organomineral fertilizer (OMF) based on food waste for the sowing of three mixtures of perennial cereals on a sample of the soil type of the Far North: an illuvial -ferruginous podzol with the aim of developing a technology for the restoration of disturbed soil cover are presented. It was revealed that when OMF is added in the amount of 25 and 50%, the physicochemical properties of the soil improve; there is an increase in the green mass of plants relative to control by an average of 3.3 times. When 50% of this fertilizer is applied, signs of plant inhibition are observed on day 18, which indicates an overabundance of nutrients in the soil. The mass of plants at this concentration is close to the values obtained at 25% OMF content. Organomineral fertilizer based on food waste with the obtained characteristics can be used in the restoration of the illuvial-ferruginous podzol as a reclamation fertilizer. Keywords: organic-mineral fertilizer, perennial cereals, physicochemical properties of soils.
Impact of environmental factors on agrofibers based on “green” polymers
Authors: Tertyshnaya Yu V , Olkhov A A , Levina N S , Bidey I A , Moskovskiy M N
Published: September 2020

Influence of different environmental factors on the degradation of fibrous samples based on polylactic acid and poly-3-hydroxybuturate was studied in this work. The article presents data obtained by differential scanning calorimetry (DSC), scanning electron microscopy (SEM). The hydrolytic degradation of nonwoven fibers, degradation in soil and under UV light were investigated. It was found that the degree of degradation of the material obtained from the 5% PHB solution was higher than from 7 and 9 %. It was shown that after 60 days of soil exposure, the samples of nonwoven fibers PLA and PLA-PHB collapsed into fragments and melting temperature of both samples was reduced by 11-12 °C. The degree of crystallinity also significantly decreased.
Distress and Type 2 Diabetes Self-Care: Putting the Pieces Together
Authors: Hoogendoorn Claire J , Schechter Clyde B , Llabre Maria M , Walker Elizabeth A , Gonzalez Jeffrey S
Published: September 2020

Background

Conflicting research emphasizes depression, diabetes distress, or well-being in relation to diabetes self-care and risk for poor health outcomes.

Purpose

The purpose of this study was to test whether a latent variable for general psychological distress derived from shared variance of depression symptoms, diabetes distress, and well-being predicts a latent variable of diabetes self-care and to examine evidence for unique effects once shared effects are adjusted for.

Methods

Adults with suboptimally controlled diabetes were recruited from the South Bronx, NY, for a telephonic diabetes self-management support trial. Baseline diabetes self-care, medication adherence, depression symptoms, diabetes distress, and well-being were measured by validated self-report. Structural equation modeling specified a latent variable for general psychological distress derived from shared variance of depression symptoms, diabetes distress, and well-being. Diabetes self-care was a latent variable indicated by diet, glucose self-monitoring, and medication adherence.

Results

Participants (N = 627, 65% female) were predominantly ethnic minority (70% Hispanic; 45% Black) and 77% reported household income <$20K/year. Mean (standard deviation) age = 56 (12) years; A1c = 9.1% (1.9%); body mass index = 32 (8) kg/m2. The latent variable for psychological distress was a robust predictor of poorer diabetes self-care (coefficient = −0.59 [confidence interval = −0.71, −0.46], p < .001) with good model fit. Unique paths from depression symptoms, diabetes distress, and well-being (all ps > .99) to self-care were not observed.

Conclusions

In this population of disadvantaged adults with suboptimally controlled diabetes, general psychological distress was strongly associated with poorer diabetes self-care and fully accounted for the effects of depression, diabetes distress, and positive well-being. This suggests that general distress may underlie previously reported associations between these constructs and diabetes self-care.
Bronchiolar Adenoma/Pulmonary Ciliated Muconodular Papillary Tumor
Authors: Shirsat Hemlata , Zhou Fang , Chang Jason C , Rekhtman Natasha , Saqi Anjali , Argyropoulos Kimon , Azour Lea , Simms Anthony , Melamed Jonathan , Hung Yin P , Roden Anja C , Mino-Kenudson Mari , Moreira Andre L , Narula Navneet
Published: September 2020

Objectives

To describe the histologic features that are helpful in the diagnosis of the rare bronchiolar adenomas/ciliated muconodular papillary tumors (BAs/CMPTs) during intraoperative consultation.

Methods

Multi-institutional retrospective review of frozen sections of 18 BAs/CMPTs.

Results

In 14 of 18 cases, BA/CMPT was the primary reason for sublobar lung resection, and in 4 cases, BA/CMPT was an incidental finding intraoperatively for resections performed for carcinoma in other lobes. There were 11 proximal-type/classic BAs/CMPTs and 7 distal-type/nonclassic BAs/CMPTs. Only 3 (16.7%) of 18 were correctly diagnosed at the time of frozen section, all of which were proximal type/classic. The remainder were diagnosed as adenocarcinoma (n = 7); invasive mucinous adenocarcinoma (n = 1); non–small cell lung carcinoma (n = 1); cystic mucinous neoplasm, favor adenocarcinoma (either mucinous or colloid type) (n = 1); favor adenocarcinoma, cannot exclude CMPT (n = 1); atypical proliferation (n = 2); mucinous epithelial proliferation (n = 1); and mucous gland adenoma (n = 1).

Conclusions

BA/CMPT can potentially be misdiagnosed as carcinoma during intraoperative consultation. On retrospective review of the frozen sections, the presence of the following may help to avoid misdiagnosis: a mixture of bland ciliated columnar cells, mucinous cells, and, most important, a basal cell layer, as well as a lack of necrosis, significant atypia, and mitoses.