bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance optimization design of lightweight composite thermal insulation structure for vehicle shelter
Authors: ZENG Xiaojie , WANG Liangmo , CHEN Gang , WANG Tao , WANG Weili , LI Xiao
Published: May 2022

Aiming at the thermal insulation problem of vehicle shelter in high heat and cold environment, with polyurethane foam as the base material, vacuum insulation board and aerogel with low thermal conductivity as the core material, a new composite insulation structure called dual-core cladding thermal insulation structure suitable for vehicle shelter is proposed. Based on the secondary development of ANSYS, the batch CFD simulation of the sample points of the dual-core cladding thermal insulation structure is realized, and it is concluded that its surface density increases linearly and effective thermal conductivity decreases nonlinearly with the increasing of thickness of the core material. Comparing with aerogel, the thickness of the vacuum insulation board has a more obvious influence on the performance of the insulation structure. The proxy model and the second-generation non-inferior ranking genetic algorithm are used to perform the multi-objective optimization of performance of the dual-core cladding thermal insulation structure. After optimization, the effective thermal conductivity of the thermal insulation structure reduced by 55.56%, and the thermal insulation effect is better than that of the single-core thermal insulation structure. The new dual-core cladding thermal insulation structure was applied to the middle roof of a vehicle shelter, the analysis results showed that the heat transfer coefficient of the middle roof reduced by 15.76% under the requirement of surface density, which improved significantly the heat insulation performance of the vehicle shelter slab.
Waveform optimization technology of missile borne radar based on FSK-PSK composite modulation for anti repeater jamming
Authors: FEI Zhiting , ZHAO Min , ZHANG Jindong , LI Chen , ZHU Xiaohua
Published: May 2022

Aiming at the waveform of missile borne radar is simple and easy to be affected by the repeater jamming in the terminal guidance, an anti-jamming waveform optimization algorithm based on the frequency shift keying(FSK) and phase shift keying(PSK) composite modulation is proposed. The model function of FSK-PSK composite modulation signal is analyzed. Based on the orthogonality of sub pulses, an optimization algorithm of intra pulse PSK modulation based on the alternating direction multiplier method(ADMM) is designed. The simulation results show that comparing with PSK signal, the intra pulse sub pulse orthogonality of FSK-PSK signal optimized by modulation is improved by about 10 dB, which can effectively suppress the intra pulse forwarding interference.
Study on surface integrity of DD5 nickel-based single crystal super-alloy in creep-feed grinding
Authors: JIN Qichao , CAO Shuaishuai , WANG Wenhu , JIANG Ruisong , GUO Lei
Published: May 2022

In order to control the forming surface quality of signal crystal turbine blade tenon teeth in the creep feed grinding, the influence of the creep feed grinding parameters on the grinding surface integrity of DD5 nickel-based single crystal superalloy was investigated via orthogonal experiment. The results showed that the surface roughness along vertical grinding direction was ranged at 0.56-0.74 μm at the grinding wheel speed range of 15-30 m/s, feeding velocity range of 120-210 mm/min and grinding depth range of 0.1-0.7 mm, and the surface roughness in the grinding direction is about 1/5 of that in the vertical grinding direction. The surface topography and texture results showed that there were the obvious grooves and ridges on the grinding surface caused by the grain ploughing and scratching, the length and height of grooves and ridges on the grinding surface changed obviously under different processing parameters, and the three-dimensional topography of the grinding surface fluctuated obviously. The length of grooves and ridges along the grinding direction were sensitive to the speed of grinding wheel, waviness of grooves and ridges along the vertical grinding direction were sensitive to the grinding depth and workpiece feed rate. The different degrees of work hardening effect were presented at the grinding surface, the biggest work hardening effect achieved at 11.6%, and the maximum depth of work hardening effect was 110 μm. The distinct plastic deformation appeared at the grinding surface. The γ phase presented slip deformation along the grinding direction with various degrees, and the γ' phase presented skewing, twisting, broken and fracture, the maximum depth of plastic deformation was 2.92 μm. The work hardening effect of DD5 creep feed grinding mainly due to the plastic deformation degree at the grinding surface. The experimental conclusions provided theoretical guidance for DD5 signal crystal turbine blade tenon teeth.
Editorial
Authors: Peters Stefan , Streber René
Published: May 2022

Liebe Leserinnen und Leser,

dieses Heft widmet sich einem Thema, das uns alle betrifft: der Gesundheitskompetenz.
Als Gesundheits- wie Bewegungsfachberuf treibt uns die Frage um, wie wir die
Gesundheitskompetenz von Personen stärken und die entsprechenden
Rahmenbedingungen herstellen können, um Personen in die Lage zu versetzen,
im Alltag wie im Gesundheitssystem so agieren zu können, dass es sich
positiv auf die Gesundheit auswirkt.
Change Resistance and Clinical Practice Strategies in Audiology
Authors: Wince Jessica R. , Emanuel Diana C. , Hendy Nhung T. , Reed Nicholas S.
Published: May 2022

Abstract Background Audiology is experiencing pressure from market forces that may change the profession's nature. Research suggests that understanding resistance needs to change and organizational culture may provide insights that can facilitate change.
Purpose This study was designed to examine audiologists' resistance to change, organizational culture, and clinical practices related to hearing aid pricing and audiology assistants. Research Design This study utilized a cross-sectional and nonexperimental survey
design. Study Sample Participants were 205 U.S. audiologists, representing diversity across experience, work setting, and location. Data Collection This survey examined demographics and clinical practice strategies. Resistance to change (RTC) scale examined
disposition toward change. Organizational culture profile (OCP) examined organizational culture perspectives. Results The majority (52%) of respondents use bundled pricing but 42% of these repondents anticipate transitioning to unbundling. Use of hybrid pricing is increasing.
Service-extender personnel were reported by 41%. Although the majority (66%) do not work with audiology assistants currently, 32% of these participants anticipate they will do so in the future. Results indicated lower RTC and greater years of experience were associated with more positive perceptions
about organizational culture. Pricing structure was related to experience. Conclusion Trends indicate use of bundled pricing is decreasing, use of hybrid pricing is increasing, and employment of audiology assistants is increasing. Experienced audiologists are more likely to
report unbundled and hybrid pricing compared with less experienced audiologists.
Interactions among Variables in the P300 Response to a Continuous Performance Task
Authors: Salamat Mimi Τ. , McPherson David L.
Published: May 2022

This study investigated the effect of variable interstimulus intervals (ISIs) on behavioral reaction time (RT) and on the latency and amplitude of the auditory P300 using an auditory continuous performance task (ACPT) paradigm. Twenty subjects were instructed to respond to common stimuli and ignore a rare stimulus. Common stimuli were 1000-, 1500-, and 2000-Hz pure tones. The rare stimulus was a 250-Hz pure tone. ISIs of 1, 2, and 4 seconds were used for this investigation. A significant correlation between ISI, reaction time, P300 latency, correct rejections, and false alarm rates was found. A significant correlation between P300 latency, Ρ amplitude, correct rejections, and false alarm rates was also observed. Likewise, a statistically significant increase in reaction time (RT) was observed as ISI increased. The ACPT paradigm in conjunction with the auditory P300 response can measure both behavioral and electrophysiologic changes that occur during active auditory attention and auditory cognitive processing tasks.

Abbreviations: ACPT = auditory continuous performance task, ADHD = attention deficit hyperactivity disorder, AERP = auditory event-related potential, CAPD = central auditory processing disorder, CCPT = Conner's continuous performance task, CPT = continuous performance task, ISI = interstimulus interval, RT = reaction time, VCPT = visual continuous performance task, VERP = visual event-related potential
Mismatch Negativity to Acoustic Differences Not Differentiated Behaviorally
Authors: Dalebout Susan D. , Stack Janet W.
Published: May 2022

Mismatch negativity (MMN) reportedly reflects the neurophysiologic detection of acoustic differences, rather than the phonemic categorization of speech sounds. The purpose of the present study was to determine if it is elicited by speech contrasts that are acoustically different but are not differentiated by listeners in behavioral tasks. Experimental stimuli were drawn from a synthetically generated continuum that varied in place of articulation from /da/ to /ga/. Contrasts used to elicit MMN were (a) the continuum endpoints, (b) the two-step contrast that straddled each listener's categorical boundary, and (c) a within-category contrast that was not behaviorally differentiated by any of the listeners. MMN responses were elicited by all three experimental contrasts. It appears that MMN may be an index of the neurophysiology underlying the ability or inability to discriminate the acoustic parameters necessary for speech perception, rather than a neurophysiologic correlate of behavioral speech discrimination ability. However, limitations involving identification of MMN in the responses of individual listeners confounded this interpretation.

Abbreviations: 1–9 contrast = contrast between stimulus continuum endpoints, 7–9 contrast = contrast between steps 7 and 9 on the stimulus continuum, Cz = vertex, F1-F5 = first through fifth formants, Fz = 30 percent of the distance between nasion and inion at the midline, listener MAX = the two-step stimulus contrast that was discriminated best by each listener, MMN = mismatch negativity
Theoretical study on Xe⋯N non-covalent interactions: Three hybridization N with XeO3 and XeOF2
Authors: Ji Su-jun , Ding Zhi-ling , Yin Hang , Zheng Dao-yuan , Zhao Jin-feng
Published: May 2022

The interactions of complexes of XeOF2 and XeO3 with a series of different hybridization N-containing donors are studied by means of DFT and MP2 calculations. The aerogen bonding interaction energies range from 6.5 kcal/mol to 19.9 kcal/mol between XeO3 or XeOF2 and typical N-containing donors. The sequence of interaction for N-containing hybridization is sp3>sp2>sp, and XeO3 is higher than XeOF2. For some donors of sp2 and sp3 hybridization, the steric effect plays a minor role in the interaction with the evidence of reduced density gradient plots. The dominant stable part is the electrostatic interaction. In complex of XeO3, the weight of polarization is larger than dispersion, while the situation is opposite for XeOF2 complexes. Except for the sum of the maximum value of molecular electrostatic potential on Xe atom and minimum value of molecular electrostatic potential on N atom, the otherfive interaction parameters including the potential energy density at bond critical point, the equilibrium distances, interaction energies with the basis set superposition error correction, localized molecular orbital energy decomposition analysis interaction energies, and the electron charge density, show great linear correlation coefficients with each other.
Regulation of excited-state intramolecular proton transfer process and photophysical properties for benzoxazole isothiocyanate fluorescent dyes by changing atomic electronegativity
Authors: Zhang Hongling , Liu Qingtong , Wang Yiying , Tang Zhe , Zhou Panwang
Published: May 2022

Excited-state intramolecular proton transfer (ESIPT) is favored by researchers because of its unique optical properties. However, there are relatively few systematic studies on the effects of changing the electronegativity of atoms on the ESIPT process and photophysical properties. Therefore, we selected a series of benzoxazole isothiocyanate fluorescent dyes (2-HOB, 2-HSB, and 2-HSeB) by theoretical methods, and systematically studied the ESIPT process and photophysical properties by changing the electronegativity of chalcogen atoms. The calculated bond angle, bond length, energy gap, and infrared spectrum analysis show that the order of the strength of intramolecular hydrogen bonding of the three molecules is 2-HOB<2-HSB<2-HSeB. Correspondingly, the magnitude of the energy barrier of the potential energy curve is 2-HOB>2-HSB>2-HSeB. In addition, the calculated electronic spectrum shows that as the atomic electronegativity decreases, the emission spectrum has a redshift. Therefore, this work will offer certain theoretical guidance for the synthesis and application of new dyes based on ESIPT properties.
Existence analysis of a stationary compressible fluid model for heat-conducting and chemically reacting mixtures
Authors: Bulíček Miroslav , Jüngel Ansgar , Pokorný Milan , Zamponi Nicola
Published: May 2022

The existence of large-data weak solutions to a steady compressible Navier–Stokes–Fourier system for chemically reacting fluid mixtures is proved. General free energies are considered satisfying some structural assumptions, with a pressure containing a γ-power law. The model is thermodynamically consistent and contains the Maxwell–Stefan cross-diffusion equations in the Fick–Onsager form as a special case. Compared to previous works, a very general model class is analyzed, including cross-diffusion effects, temperature gradients, compressible fluids, and different molar masses. A priori estimates are derived from the entropy balance and the total energy balance. The compactness for the total mass density follows from an estimate for the pressure in Lp with p > 1, the effective viscous flux identity, and uniform bounds related to Feireisl’s oscillation defect measure. These bounds rely heavily on the convexity of the free energy and the strong convergence of the relative chemical potentials.
Logarithmic spiral solutions of the Kopell–Howard lambda–omega reaction–diffusion equations
Authors: Troy William C.
Published: May 2022

Our investigation of logarithmic spirals is motivated by disparate experimental results: (i) the discovery of logarithmic spiral shaped precipitate formation in chemical garden experiments. Understanding precipitate formation in chemical gardens is important since analogous precipitates form in deep ocean hydrothermal vents, where conditions may be compatible with the emergence of life. (ii) The discovery that logarithmic spiral shaped waves of spreading depression can spontaneously form and cause macular degeneration in hypoglycemic chick retina. The role of reaction–diffusion mechanisms in spiral formation in these diverse experimental settings is poorly understood. To gain insight, we use the topological shooting to prove the existence of 0-bump stationary logarithmic spiral solutions, and rotating logarithmic spiral wave solutions, of the Kopell–Howard lambda–omega reaction–diffusion model.
Propagation characteristics of relativistic ultrashort laser pulse in inhomogeneous plasma
Authors: Zhang Xiao-Bo , Huang Mao , Tang Rong-An , Zhang Ai-Xia , Xue Ju-Kui
Published: May 2022

We study the propagation of a relativistic ultrashort laser pulse in two-dimensional inhomogeneous plasma with a density ripple based on the theoretical analysis and the particle-in-cell simulation. An analytical solution of the laser pulse propagating in the homogeneous plasma is completely obtained. It is found that the stable propagation of the relativistic ultrashort laser pulse in homogeneous plasma can be realized, and the propagation distance and intensity of the laser pulse and the spatial distribution of electron density can be effectively modulated by adjusting the pulsewidth of the incident laser and the plasma frequency. More interestingly, in the inhomogeneous plasma with a density ripple, when the wave amplitude of the density ripple is less than a critical value, the intensity of the ultrashort laser pulse is almost unchanged and the propagation characteristics of the laser in the inhomogeneous plasma are basically consistent with those in the homogeneous plasma. However, when the wave amplitude of the density ripple is larger than the critical value, the inhomogeneity of the plasma has an obvious effect on the laser characteristics, and the intensity and the spatial distribution of the laser pulse will be modulated by the plasma density ripple. The influence of the laser pulsewidth, plasma density, and plasma density ripple on the laser characteristics is discussed in detail.
Simulation study of coupled two-stream and current filamentation instability excited by accelerator electron beams in plasmas
Authors: Li Han-Lin , Hu Zhang-Hu , Zhao Quan-Tang , Cheng Rui , Zhao Yong-Tao , Zhang Zi-Min , Li Xue-Chun , Wang You-Nian
Published: May 2022

A gas-discharge plasma device is simulated with COMSOL software, and the obtained plasma density profile is input into a two-dimensional particle-in-cell code, in which the transport of relativistic electron beams in the plasma with an actual density profile is investigated. The results show that the device can produce a wide range of high-density plasmas with the maximum density approaching 5.25×1022 m−3. With the relativistic electron beams produced from a linear electron accelerator, the gas-discharge plasma is shown to be an ideal medium for the investigation of coupled two-stream and current filamentation instability.
Lift coefficient of bubble sliding inside turbulent boundary layers in an inclinable channel flow
Authors: Yoon Dongik , Park Hyun Jin , Tasaka Yuji , Murai Yuichi
Published: May 2022

The behavior of bubbles traveling in the proximity of a tilted wall is studied experimentally to understand the fundamental sliding motion of bubbles inside turbulent boundary layers along an inclined wall. The qualitative visualization of sliding bubbles confirms the contribution of bubble buoyancy on the sliding motion for negative and positive inclinations of the channel. An opto-acoustic combined measurement technique is adopted to explore the sliding motion. Liquid velocity profiles in the bubbly flow and the distance between the wall and bottom of the bubble are obtained using the ultrasound pulsed Doppler method, while the bubble diameters and velocities are obtained from particle-tracking type image processing. The combined measurements reveal that the velocity of bubbles decreases under the negative slope condition and increases under the positive slope condition due to opposite buoyancy effects. In addition, the distance between the wall and bottom of the bubble increases with an increase in negative inclination. The lift coefficient is derived from the measured variables using a force–balance equation among the buoyancy, lift, and surface tension. Finally, we propose modeling equations for the lift coefficient expressed in terms of the Reynolds, Weber, and Bond numbers, which apply to the bubbles inside boundary layers.
Epitaxial growth and polarized Raman scattering of niobium dioxide films
Authors: Shibuya Keisuke , Sawa Akihito
Published: May 2022

We report the structural, electrical, and optical characterization of epitaxial niobium dioxide (NbO2) films fabricated on MgF2(001) substrates. The films were almost stoichiometric, had an indirect bandgap of 0.7 eV, and exhibited a phase transition at ∼1080 K. A polarized Raman scattering study of the films was conducted to investigate the Raman symmetry in the low-temperature phase. Based on the angular-dependent polarized Raman spectra, we assigned 13 modes to Ag symmetry and 14 to Bg symmetry. We also evaluated the Raman tensor elements of the Bg modes and found that the off-diagonal elements were nearly zero in most of the Bg modes, except for a phonon mode at 267 cm−1. This study aids understanding of the lattice dynamics of NbO2, which plays a critical role in the phase transition.
Integration of electroencephalogram (EEG) and motion tracking sensors for objective measure of attention-deficit hyperactivity disorder (MAHD) in pre-schoolers
Authors: Bhattacharyya Neha , Singh Soumendra , Banerjee Amrita , Ghosh Ria , Sinha Oindrila , Das Nairit , Gayen Rajkumar , Pal Somya Shubhra , Ganguly Sahely , Dasgupta Tanmoy , Dasgupta Tanusree , Mondal Pulak , Adhikari Aniruddha , Sarkar Sharmila , Bhattacharyya Debasish , Mallick Asim Kumar , Singh Om Prakash , Pal Samir Kumar
Published: May 2022

We developed an integrated device composed of a single-probe Electroencephalogram (EEG) and Charge Coupled Device (CCD) based motion sensors for objective measurement of Attention-deficit Hyperactivity Disorder (ADHD). While the measurement of attention-deficit hyperactivity disorder (MAHD) relies on the EEG signal for the assessment of attention during a given structured task, the CCD sensor depicts the movement pattern of the subjects engaged in a continuous performance task. A statistical analysis of attention and movement patterns was performed, and the accuracy of completed tasks was analyzed using indigenously developed software. The device with the embedded software is intended to improve certainty with criterion E. We used the EEG signal from a single-channel dry sensor placed on the frontal lobe of the head of the subjects (3–5 year old pre-schoolers). During the performance of the task power for delta and beta, EEG waves from the subjects are found to be correlated with relaxation and attention/cognitive load conditions. While the relaxation condition of the subject hints at hyperactivity, a more direct CCD-based motion sensor is used to track the physical movement of the subject engaged in a continuous performance task. We used our indigenously developed software for statistical analysis to derive a scale for the objective assessment of ADHD. We also compared our scale with clinical ADHD evaluations and found a significant correlation between the objective assessment of the ADHD subjects and the clinician’s conventional evaluation. MAHD, the integrated device, is supposed to be an auxiliary tool to improve the accuracy of ADHD diagnosis by supporting greater criterion E certainty.
Dynamic analysis of the sinusoidal actuation of a flexible fin for paired fin propulsion
Authors: Su Zhengguo , Yu Fusheng , Zhu Baoxing , Han Wenjun , Wang Qingda , Li Wentao
Published: May 2022

In this research, the sinusoidal actuation of a flexible fin for median and/or paired fin propulsion is studied. A prototype of an underwater robot is built, and the computer-aided engineering simulation method is used for the transmission system of the flexible fin. The fin ray at the end of the trajectory and the crankshaft drive the parameters as a function of the fin ray output parameters. Given the fin and the fin surface motion for the coupled simulation analysis, the flexible fin surface and the fin sinusoidal oscillation are studied. The deformation of the fin surface is established outside the edge wave trajectory equation of motion. The equations of motion are verified by simulation. The single fin wave model is solved with the computational fluid dynamics method, and the hydrodynamic performance of the fin surface is obtained. Using the dynamic mesh technique, the complex large fluctuation motion of the fin surface is solved. With different amplitudes and periods of the fin wave as the input parameters, a simulation of the fin wave propulsion is conducted, and the relationship between the fin wave propulsion force and the fin wave resistance is calculated. The correctness of the simulation results of the sinusoidal fixed wave of the fin surface is verified by a fin wave ink experiment.
Energy preserving reduced-order modeling of the rotating thermal shallow water equation
Authors: Karasözen B. , Yıldız S. , Uzunca M.
Published: May 2022

In this paper, reduced-order models (ROMs) are developed for the rotating thermal shallow water equation (RTSWE) in the non-canonical Hamiltonian form with state-dependent Poisson matrix. The high fidelity full solutions are obtained by discretizing the RTSWE in space with skew-symmetric finite-differences, while preserving the Hamiltonian structure. The resulting skew-gradient system is integrated in time by the energy preserving average vector field (AVF) method. The ROM is constructed by applying proper orthogonal decomposition with the Galerkin projection, preserving the reduced skew-gradient structure, and integrating in time with the AVF method. The nonlinear terms of the Poisson matrix and Hamiltonian are approximated with the discrete empirical interpolation method to reduce the computational cost. The solutions of the resulting linear-quadratic reduced system are accelerated by the use of tensor techniques. The accuracy and computational efficiency of the ROMs are demonstrated for a numerical test problem. Preservation of the energy (Hamiltonian) and other conserved quantities, i.e., mass, buoyancy, and total vorticity, show that the reduced-order solutions ensure the long-term stability of the solutions while exhibiting several orders of magnitude computational speedup over the full-order model. Furthermore, we show that the ROMs are able to accurately predict the test and training data and capture the system behavior in the prediction phase.
Water use efficiency in Western Australian cropping systems
Authors: Harries Martin , Flower Ken C. , Renton Michael , Anderson Geoffrey C.
Published: May 2022

Rotations and associated management practices in rainfed farming systems of southwest Australia have shifted towards intensified cropping. Survey data from 184 fields spanning 14 Mha of southwest Australia were used to document water use efficiency (WUE) and water-limited yield potential (WLYP) of commercial crops and crop sequences and identify biophysical variables influencing WUE. WUE achieved in commercial wheat crops was 10.7 kg grain/ha.mm. Using a boundary function Ywl = 25 × (WU − 45), farmers achieved 54% of WLYP. Climate variables affected WUE more than management and biotic variates, the highest latitude region having WUE of 9.0 kg grain/ha.mm, compared to 11.8 kg grain/ha.mm for regions further south. Increased soil nitrogen and nitrogen fertiliser increased WUE, as did sowing earlier; in keeping with farmers in southern Australia sowing crops earlier and trebling fertiliser nitrogen usage since 1990. Wheat yield and WUE increased a small amount after break crop or pasture (12.5 kg grain/ha.mm) compared to wheat grown after wheat (11.2 kg grain/ha.mm), due to good weed and root pathogen control, and high fertiliser nitrogen application. However, WUE of wheat declined to 8.4 kg grain/ha.mm when more than three wheat crops were grown in succession. Farmers continue to improve WUE with increased inputs and new technologies replacing some traditional functions of break crops and pasture. However, break crops and pastures are still required within the rotation to maintain WUE and break effects need to be measured over several years.
-Carnitine improves follicular survival and function in ovarian grafts in the mouse
Authors: Sanamiri Khadijeh , Soleimani Mehranjani Malek , Shahhoseini Maryam , Shariatzadeh Mohammad Ali
Published: May 2022

Context Ovarian tissue transplantation is performed to preserve fertility in patients undergoing chemotherapy and radiotherapy. However, the ischemia-reperfusion injury which occurs after the ovarian tissue transplantation causes follicular depletion and apoptosis. l-Carnitine has antioxidant and anti-inflammation properties. Aims Therefore, we aimed to investigate the beneficial effect of l-carnitine on mouse ovaries following heterotopic autotransplantation. Methods Mice were randomly divided into three groups (six mice per group): control, autografted and autografted + l-carnitine (200 mg/kg daily intraperitoneal injections). Seven days after ovary autografting, the serum levels of malondialdehyde (MDA), total antioxidant capacity, tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-10 were measured. Ovary histology, serum concentrations of progesterone and estradiol were also measured 28 days after autotransplantation. Data were analysed using one-way analysis of variance (ANOVA) and Tukey test, and the means were considered significantly different at P < 0.05. Key results In the autografted + l-carnitine group, the total volume of the ovary, the volume of the cortex, the number of follicles, the serum concentrations of IL-10, estradiol and progesterone significantly increased compared to the autografted group. In the autografted + l-carnitine group, serum concentrations of IL-6, TNF-α and MDA were significantly decreased compared to the autografted group. Conclusions Our results indicated that l-carnitine can ameliorate the consequences of ischemia-reperfusion on the mice ovarian tissue following autotransplantation. Implications l-carnitine improves the structure and function of transplanted ovaries.
Individual and network factors associated with HIV self-testing among men who have sex with men in resource-limited settings in China
Authors: Yang Xing , Jiang Li , Fang Ting , Huang Jiegang , Tan Sumin , Lu Chunyan , Zhu Jiawen , Huang Haimei , Wang Min , Zhang Yun , Liang Hao , Cen Ping , Ning Chuanyi
Published: May 2022

Background HIV self-testing (HIVST) is a potential strategy to overcome challenges of HIV testing among men who have sex with men (MSM). However, for resource-limited settings, technology and diagnostic devices are lagging. Hence, we estimated the status and correlates of HIVST among MSM in resource-limited settings in China to inform the development of HIVST to reach United Nations Programme on HIV and AIDS (UNAIDS) targets to end HIV by 2030. Methods A cross-sectional study was conducted among MSM in Nanning, Guangxi, China, between August 2019 and January 2020. The HIVST status was collected and data on social network features, sociodemographic information, risk behaviours, etc. were compared between prior- and non-HIVST MSM. Logistic regression analyses were conducted to examine the correlates of HIVST. Results The prevalence of HIVST among 446 MSM was 40.4% (95% confidence interval [CI] 35.8–44.9%). The main component of sociocentric network contains more prior-HIVST MSM (38.3%) than non-HIVST MSM (28.6%, P = 0.031). More MSM with individual features such as substance use during anal sex (22.8% vs 15.4%, P = 0.049) and multiple sexual partners (76.1% vs 59.4%, P < 0.001) were detected among prior-HIVST MSM. In multivariable analysis, prior HIVST was associated with the strong strength of ego-alter ties in the egocentric network (adjusted odds ratio [aOR] 1.72; 95% CI 1.09–2.71), HIV-infected partners (aOR, 7.17; 95% CI, 1.40–36.60), and vaginal intercourse (aOR, 0.38; 95% CI, 0.17–0.85). Conclusions HIVST coverage among MSM in resource-limited settings is suboptimal. Integrating social networks into testing services may be viable to promote HIVST in MSM within resource-limited settings.
A novel regulatory gene promotes novel cell fate by suppressing ancestral fate in the sea anemoneNematostella vectensis
Authors: Babonis Leslie S. , Enjolras Camille , Ryan Joseph F. , Martindale Mark Q.
Published: May 2022

Significance

In this study, we demonstrate how a new cell type can arise through duplication of an ancestral cell type followed by functional divergence of the new daughter cell. Specifically, we show that stinging cells in a cnidarian (namely, a sea anemone) emerged by duplication of an ancestral neuron followed by inhibition of the RFamide neuropeptide it once secreted. This finding is evidence that stinging cells evolved from a specific subtype of neurons and suggests other neuronal subtypes may have been coopted for other novel secretory functions.
The cyclic octapeptide antibiotic argyrin B inhibits translation by trapping EF-G on the ribosome during translocation
Authors: Wieland Maximiliane , Holm Mikael , Rundlet Emily J. , Morici Martino , Koller Timm O. , Maviza Tinashe P. , Pogorevc Domen , Osterman Ilya A. , Müller Rolf , Blanchard Scott C. , Wilson Daniel N.
Published: May 2022

Significance

The increase in multidrug-resistant bacteria highlights the urgent need for compounds with novel target sites that can be developed as antibiotics. The argyrins represent a family of naturally produced octapeptides that display promising activity against
Pseudomonas aeruginosa
by inhibiting protein synthesis. Our structural and kinetic analyses reveal that argyrins inhibit protein synthesis by interacting with, and trapping, the translation elongation factor G (EF-G) on the ribosome, analogous to that reported previously for the unrelated antibiotic fusidic acid. However, the binding site of argyrin on EF-G is distinct from that of fusidic acid, indicating that intramolecular movements at the domain III/V interface of EF-G are also essential for facilitating late events in the translocation mechanism.
Garnet secondary ion mass spectrometry oxygen isotopes reveal crucial roles of pulsed magmatic fluid and its mixing with meteoric water in lode gold genesis
Authors: Fan Gao-Hua , Li Jian-Wei , Valley John W. , Scicchitano Maria Rosa , Brown Philip E. , Yang Jin-Hui , Robinson Paul T. , Deng Xiao-Dong , Wu Ya-Fei , Li Zhan-Ke , Gao Wen-Sheng , Li Si-Yuan , Zhao Shao-Rui
Published: May 2022

Significance

There is a common consensus that lode gold deposits mostly precipitated from metamorphic fluids via fluid boiling and/or fluid–rock interaction, but whether magmatic hydrothermal fluids and the mixing of such fluids with an external component have played a vital role in the formation of lode gold deposits remains elusive. We use garnet secondary ion mass spectrometry oxygen isotope analysis to demonstrate that the world-class Dongping lode gold deposit has been formed by multiple pulses of magmatic hydrothermal fluids and their mixing with large volumes of meteoric water. This study opens an opportunity to tightly constrain the origin of lode gold deposits worldwide and other hydrothermal systems that may have generated giant ore deposits in the Earth’s crust.
Cryo-EM structures show the mechanistic basis of pan-peptidase inhibition by human α2-macroglobulin
Authors: Luque Daniel , Goulas Theodoros , Mata Carlos P. , Mendes Soraia R. , Gomis-Rüth F. Xavier , Castón José R.
Published: May 2022

Human α2-macroglobulin (hα2M) is a multidomain protein with a plethora of essential functions, including transport of signaling molecules and endopeptidase inhibition in innate immunity. Here, we dissected the molecular mechanism of the inhibitory function of the ∼720-kDa hα2M tetramer through eight cryo–electron microscopy (cryo-EM) structures of complexes from human plasma. In the native complex, the hα2M subunits are organized in two flexible modules in expanded conformation, which enclose a highly porous cavity in which the proteolytic activity of circulating plasma proteins is tested. Cleavage of bait regions exposed inside the cavity triggers rearrangement to a compact conformation, which closes openings and entraps the prey proteinase. After the expanded-to-compact transition, which occurs independently in the four subunits, the reactive thioester bond triggers covalent linking of the proteinase, and the receptor-binding domain is exposed on the tetramer surface for receptor-mediated clearance from circulation. These results depict the molecular mechanism of a unique suicidal inhibitory trap.
Autistic traits, working memory, and L2 prosodic boundary detection
Authors: Kuo Chen-Hsiu Grace
Published: May 2022

This study aims to examine the roles of second language (L2) learners’autistic traitsandworking memory capacityin detecting prosodic boundaries. Forty-six learners of English with Mandarin as their native language completed questionnaires on personality and cognitive assessment – an Autism-Spectrum Quotient questionnaire (AQ) and a Working Memory questionnaire (WM). They also completed a Rapid Prosody Transcription (RPT) task in which they were asked to mark prosodic boundaries produced by Barack Obama in recordings of his Weekly Address. The results revealed that autistic traits and working memory capacity were positively correlated with each other, andattention to detailwas the primary predictor for the detection ofboundary tones. These findings provide insight into L2 learners’ detection of prosodic boundaries along the autistic traits and working memory capacity continuum and further indicate that EFL instructions should take individual differences into consideration when assessing L2 learners’ performance in listening or comprehension tasks.
En los orígenes del estudio de la variación lingüística
Authors: Ávila-Muñoz Antonio Manuel
Published: May 2022

Abstracta

Este trabajo muestra los resultados de los análisis de los efectos que ejercen las variables estratificacionales y
personales sobre un conjunto de variables léxicas obtenidas a partir de un muestreo basado en pruebas de disponibilidad léxica.
Apoyados en una herramienta semiautomática de análisis léxico (Annotate), se construyen tres medidas que
constituyen las variables dependientes: Índice de Amplitud Léxica (IAL, número de palabras aportadas por cada informante en sus
listas), Índice de Descentralización Léxica (IDL, capacidad léxica individual) e Índice de Vocablos Especializados (IVE, número de
tecnicismos contenido en las listas). Los resultados son esperanzadores: aunque las correlaciones más fuertes se observan con las
variables de hablante tradicionales (educación, profesión y clase social, esencialmente), otras variables capaces de medir el
acceso a vías de información tras el período escolar demuestran que la desigualdad educacional no determina fatalmente las
opciones de ampliación del vocabulario ni el empleo de vocablos especializados.
Microstructural adjustment of hot-rolled Ti–6Al–4V based on a CCT diagram
Authors: Janda Alexander , Ebenbauer Stefan , Prestl Aude , Siller Ingo , Clemens Helmut
Published: May 2022

The effects of post-processing heat treatments on hot-rolled Ti–6Al–4V with extra low interstitial concentration were investigated. The 2 mm sheets were rolled in the single β phase field region and subsequently cooled in air. A continuous cooling transformation (CCT) diagram was generated, revealing the strong influence of the cooling rate on both microstructure and hardness. Cooling rates between 0.01 and 200°C s−1 were selected. While rapid cooling resulted in a martensitic transformation β → α′, a decrease in the cooling rate led to a progressive spheroidization of the lamellar (α + β) microstructure. With a focus on the established CCT continuous cooling transformation diagram, this study contains insight on the microstructure evolution of the Ti–6Al–4V ELI alloy during cooling from the single β phase field region.
Interfacial bonding and abrasive wear behaviours of the iron matrix composites
Authors: Li Cong , Shi Jing , Li Yuehui , Li Yefei , Gao Yimin , Li Bo , Goei Ronn , Cheng Chunyu , Zhao Siyong , Yoong Tok Alfred Iing
Published: May 2022

Ceramic particles reinforced iron matrix composites attract considerable interest in the industrial engineering field due to the ceramic's excellent fatigue and wear resistance. ZTA ceramic particle has been regarded as an ideal reinforcement phase. In this study, three-body abrasive wear behaviours and the mechanism of the ZTA/Fe composites and high chromium white cast iron Cr15 standard samples were investigated. The wear resistance of the ZTA/Fe composite was superior to the Cr15 standard sample under SiO2 abrasives. The extruded ZTA could protect the matrix surrounding ZTA ceramic particles. However, ZTA ceramic particles were cut together with the Cr15 matrix under SiC abrasives. The wear mechanism of the composites was a combination of the cutting and fatigue for SiC abrasives.
Effect of thermomechanical processing on microstructure characteristics of γ-TiAl-based alloy
Authors: Xuanyuan Yaodong , Lv Chengcheng , Chen Cai , Yan Yinbiao , Yang Sen
Published: May 2022

In this study, the grain boundary character distribution (GBCD) of the γ-TiAl-based alloy was modified through the thermomechanical processing route. A compression test was conducted to identify the mechanical property improvements based on the grain boundary engineering (GBE) treatment. After multidirectional isothermal forging (MDIF) and annealing, the average grain size was refined to 20 µm. The length ratio of the low Σ (1 ≤ Σ ≤ 29) coincidence site lattice (CSL) boundaries increased to 64.01%, with the alloy exhibiting a higher compressive strength (2913 MPa) and maximum compression ratio (45.3%), owing to the strengthening mechanism of grain boundaries and dislocations. Consequently, the combination of MDIF and annealing could be used for grain refinement and tuning GBCD of γ-TiAl-based alloys.
“The Idea is to Help People Achieve Greater Success and Liberty”: A Qualitative Study of Expanded Methadone Take-Home access in Opioid use Disorder Treatment
Authors: Suen Leslie W. , Castellanos Stacy , Joshi Neena , Satterwhite Shannon , Knight Kelly R.
Published: May 2022

Background: Prior to the COVID-19 pandemic, the United States (US) was already facing an epidemic of opioid overdose deaths. Overdose deaths continued to surge during the pandemic. To limit COVID-19 spread and to avoid disruptions in access to medications for opioid use disorder (MOUD), including buprenorphine and methadone, US federal and state agencies granted unprecedented exemptions to existing MOUD guidelines for Opioid Treatment Programs (OTPs), including loosening criteria for unsupervised take-home doses. We conducted a qualitative study to evaluate the impact of these policy changes on MOUD treatment experiences for providers and patients at an OTP in California. Methods: We interviewed 10 providers (including two physicians, five social worker associates, and three nurse practitioners) and 20 patients receiving MOUD. We transcribed, coded, and analyzed all interviews to identify emergent themes. Results: Patient participants were middle-aged (median age 51 years) and were predominantly men (53%). Providers discussed clinical decision-making processes and experiences providing take-homes. Implementation of expanded take-home policies was cautious. Providers reported making individualized decisions, using patient factors to decide if benefits outweighed risks of overdose and misuse. Decision-making factors included patient drug use, overdose risk, housing status, and vulnerability to COVID-19. New patient groups started receiving take-homes and providers noted few adverse events. Patients who received take-homes reported increased autonomy and treatment flexibility, which in turn increased likelihood of treatment stabilization and engagement. Patients who remained ineligible for take-homes, usually due to ongoing non-prescribed opioid or benzodiazepine use, desired greater transparency and shared decision-making. Conclusion: Federal exemptions in response to COVID-19 led to the unprecedented expansion of access to MOUD take-homes within OTPs. Providers and patients perceived benefits to expanding access to take-homes and experienced few adverse outcomes, suggesting expanded take-home policies should remain post-COVID-19. Future studies should explore whether these findings are generalizable to other OTPs and assess larger samples to quantify patient-level outcomes resulting from expanded take-home policies.
A Qualitative Study of Patient Experiences with Telemedicine Opioid use Disorder Treatment during COVID-19
Authors: Lockard Rachel , Priest Kelsey C. , Gregg Jessica , Buchheit Bradley M.
Published: May 2022

Background: The drug-related overdose crisis worsened during the COVID-19 pandemic. Recent drug policy changes to increase access to medications for opioid use disorder (MOUD) during COVID-19 shifted some outpatient MOUD treatment into virtual settings to reduce the demand for in-person care. The objective of this study was to qualitatively explore what is gained and lost in virtual patient encounters for patients with opioid use disorder at a low-threshold, addiction treatment clinic that offers buprenorphine and harm reduction services. Methods: Patients were included in this study if they received care at the Harm Reduction and BRidges to Care (HRBR) clinic and utilized virtual visits between November 2019 and March 2021. The study was conceptualized using a health care access framework and prior studies of telemedicine acceptability. Semi-structured interviews were completed between March and April 2021. Interviews were dual-coded and analyzed using directed content analysis. Results: Nineteen interviews were conducted. The sample was predominantly White (84%) and stably housed (79%) with comparable gender (male, 53%) and employment status (employed, 42%). The majority (63%) of patients preferred virtual visits compared to in-person visits (16%) or a combination of access to both (21%). Two overarching tandem domains emerged: availability-accommodation and acceptability-appropriateness. Availability-accommodation reflected participants’ desires for immediate services and reduced transportation and work or caregiving scheduling barriers, which was facilitated by virtual visits. The acceptable-appropriate domain articulated how participants felt connected to their providers, whether through in-person interactions or the mutual trust experienced during virtual visits. Conclusions: Virtual visits were perceived by participants as a valuable and critical option for accessing treatment for OUD. While many participants preferred virtual visits, some favored face-to-face visits due to relational and physical interactions with providers. Participants desired flexibility and the ability to have a choice of treatment modality depending on their needs.
Varied female and male courtship behavior facilitated the evolution of a novel sexual signal
Authors: Fitzgerald Sophia L , Anner Sophia C , Tinghitella Robin M
Published: May 2022

Sexual selection can contribute to speciation when signals and preferences expressed during mate choice are coupled within groups, but come to differ across groups (generating assortative mating). When new sexual signals evolve, it is important to investigate their roles in both mate location and courtship contexts, as both signaling functions are critical in mate choice. In previous work, researchers identified two new male morphs (silent and purring) in Hawaiian populations of the Pacific field cricket, Teleogryllus oceanicus. These morphs likely evolved because they protect males from an acoustically orienting parasitoid, yet still obtain some reproductive success. But, it remains unknown how the purring morph functions in close courtship encounters. We compared the relative success of the very recently evolved purring morph to that of the ancestral and silent morphs during courtship encounters. Purring males produce a novel courtship song and were not as successful in courtship as the ancestral type, but were mounted by females as often and as quickly as the obligately silent morph that arose and spread ~20 years ago. Purring males initiate courtship more quickly than other morphs, and females from populations where purring is common exhibit higher overall mounting rates. Thus, differences in the behavior of purring males and of females from populations where purring is common may have facilitated the origin of this novel sexual signal. We found no assortative mating between males of a given morph and females from their own population, and so we hypothesize that multiple male types will be maintained within the species because each achieves fitness in different ways.