bluuebunny/crossref_metadata_2025 huggingface dataset:
Vascular dysfunction in COVID-19 patients: update on SARS-CoV-2 infection of endothelial cells and the role of long non-coding RNAs
Authors: Pelisek Jaroslav , Reutersberg Benedikt , Greber Urs F , Zimmermann Alexander
Published: November 2022

Although COVID-19 is primarily a respiratory disease, it may affect also the cardiovascular system. COVID-19 patients with cardiovascular disorder (CVD) develop a more severe disease course with a significantly higher mortality rate than non-CVD patients. A common denominator of CVD is the dysfunction of endothelial cells (ECs), increased vascular permeability, endothelial-to-mesenchymal transition, coagulation, and inflammation. It has been assumed that clinical complications in COVID-19 patients suffering from CVD are caused by SARS-CoV-2 infection of ECs through the angiotensin-converting enzyme 2 (ACE2) receptor and the cellular transmembrane protease serine 2 (TMPRSS2) and the consequent dysfunction of the infected vascular cells. Meanwhile, other factors associated with SARS-CoV-2 entry into the host cells have been described, including disintegrin and metalloproteinase domain-containing protein 17 (ADAM17), the C-type lectin CD209L or heparan sulfate proteoglycans (HSPG). Here, we discuss the current data about the putative entry of SARS-CoV-2 into endothelial and smooth muscle cells. Furthermore, we highlight the potential role of long non-coding RNAs (lncRNAs) affecting vascular permeability in CVD, a process that might exacerbate disease in COVID-19 patients.
Self-Report of Voice Model Usage Within the Nonbinary and Gender-Nonconforming Populations
Authors: Hosbach-Cannon Carly Jo , Miholics Kallie , Zendano Alana
Published: November 2022

Purpose:

Nonbinary and gender-nonconforming identities are seeking speech-language pathology services more than ever; however, their needs do not fit into the current rhetoric surrounding gender-affirming communication modification. At present, there are limited peer-reviewed data, assessment materials, or evidence-based techniques to achieve a gender-neutral voice or communication style. In addition, what constitutes a gender-neutral voice is left to broad interpretation. This research note provides descriptive information on voice models self-reported by gender-diverse individuals.

Method:

Voice model data were obtained from a larger survey study assessing barriers to health care and voice dysphoria in nonbinary and gender-nonconforming individuals. Demographic information and continuous speech samples were obtained from publicly available resources. Acoustic information was obtained, edited, and analyzed in Praat.

Results:

Six respondents (five assigned female at birth, one assigned male at birth) reported at least one specific person they identified as having a voice they preferred or would like to model their own voice after, for 13 total voice models (10 cisgender, three transgender). Among the voice models, average fundamental frequency was 154 Hz, average range was 381 Hz, and average minimum–maximum measures were 85–466 Hz.

Conclusions:

Specific parameters that constitute a gender-neutral voice or communication style have yet to be determined. Individuals seeking to achieve a more gender-neutral voice may have varying interpretations of what they perceive as being gender neutral. Speech-language pathologists providing gender-affirming communication modification services need to take these factors into consideration when establishing a collaborative experience for nonbinary or gender-nonconforming individuals.
Feedback Stabilization of Tank-Liquid System with Robustness to Wall Friction
Authors: Karafyllis Iasson , Vokos Filippos , Krstic Miroslav
Published: November 2022

We solve the feedback stabilization problem for a tank, with friction, containing a liquid modeled by the viscous Saint-Venant system of Partial Differential Equations. A spill-free exponential stabilization is achieved, with robustness to the wall friction forces. A Control Lyapunov Functional (CLF) methodology with two different Lyapunov functionals is employed. These functionals determine specific parameterized sets which approximate the state space. The feedback law is designed based only on one of the two functionals (which is the CLF) while the other functional is used for the derivation of estimates of the sup-norm of the velocity. The feedback law does not require the knowledge of the exact relation of the friction coefficient. Two main results are provided: the first deals with the special case of a velocity-independent friction coefficient, while the second deals with the general case. The obtained results are new even in the frictionless case.
Application of Promotion Process Based on Epidemic Models Considering Bidirectionality
Authors: DUAN Zhe , DU Baojun , ZHANG Jiangang
Published: November 2022

In this paper, on the basis of previous epidemic models, we considered the bidirectionality of a certain process of the model and established the Ignorant, Exposers, Resister of product, Supporter of product, Uninterested (IERSU) model, and applied it to a new field. Firstly, the next generation matrix method was used to obtain the threshold parameter which helps to distinguish the equilibrium point of the model. Secondly, the local and global stability of the equilibrium point of the model were proved by the judgment and properties of the negative definite matrix, Lyapunov's first method and LaSalle's invariance principle. Finally, according to the numerical simulation, the influence of different parameters of the model was analyzed and a series of strategies were discussed.
Design of a high-precision, high environmental adaptability temperature measurement system for environments with large temperature variations
Authors: Yang Hongxing , Yang Ruitao , Wang Xinyue , Yin Ziqi , Hu Pengcheng , Tan Jiubin
Published: November 2022

A high-precision, high environmental adaptability thermometer based on proportional divider resistance is proposed for high-precision temperature measurement in a spaceborne environment subjected to large temperature variations. In this method, a constant voltage source was used instead of the traditional current source to increase the short-term stability of the proportional divider resistance measurement. The temperature drift characteristics of the measurement system were analyzed and compensated by the self-calibration of the reference resistance method. Based on the above-mentioned method, the minimum noise requirements were analyzed and designed for each unit of the thermometer. The temperature measurement performance of the thermometer was tested by an equivalent temperature measurement experiment with a precision resistance box and a temperature comparison experiment with platinum resistance (PT1000). The equivalent experimental results showed that the resolution of the thermometer was 0.3 mK at an ambient temperature of 20 °C and the maximum deviation of the measurement error was less than 1 mK in a large working range of 10–40 °C. The comparison experiment using a Fluke thermometer 1594A as the reference instrument showed that the standard deviation of temperature measurement was within 0.8 mK in the range of 17–23 °C.
Effects of radiation, curvature, and preferential diffusion on the extinction of laminar non-premixed flames
Authors: Gao Yushan , Han Wang , Chen Zheng , Fu Qingfei , Yang Lijun
Published: November 2022

The combined effects of radiative heat loss, curvature, and preferential diffusion on laminar non-premixed flames (or flamelets) are investigated in this work by using asymptotic analysis. A general theoretical description of flame temperature and extinction is derived for curved flames with non-unity Lewis numbers and radiative heat loss. Special attention is paid to the effects of curvature and radiative heat loss on the flammability limits. The results show that (1) a curved flamelet always has two extinction limits: one is the kinetic extinction limit, and the other is the curvature-induced extinction limit for the adiabatic case or the radiative extinction limit for the radiative case; (2) the curvature exerts a different influence on the adiabatic and radiative flames. Specifically for the adiabatic flame, it is found that both flame temperature and flame position significantly decrease as the curvature increases and that a new extinction limit at a low stretch rate occurs due to the existence of curvature. Furthermore, a higher curvature coupled with the increase in the Lewis number results in a lower flammability limit and narrower flammable zone. Therefore, the presence of curvature has a negative impact on the adiabatic flame. On the contrary, for the radiative flame, the results show that the increase in curvature has a positive effect on the flammability limit and thereby increases the flammable zone. It is expected that curved flamelets hold smaller (larger) flammable zones than planar flamelets under the adiabatic (radiative) condition. All results show that the change in flame curvature has a stronger effect on the flame structure and extinction than the deviation of the Lewis number from unity.
Linking microwave heating of aqueous spheres to morphology-dependent resonances
Authors: Song Yuchen , Shafe-Purcell John , Slepkov Aaron D.
Published: November 2022

It was recently suggested that the sparking of grape dimers in microwave ovens is due to the interaction of morphology-dependent resonances in aqueous spheres. However, evidence for microwave resonances in individual grape-sized aqueous spheres has remained weak and is open to interpretation. In this work, we provide new experimental evidence for size-dependent resonances in hydrogel spheres via calorimetric measurement of the electromagnetic energy absorbed by hydrogel spheres under microwave irradiation. Using finite-element simulations, we predict the resonant behavior of grape-sized aqueous spheres and further explore the differences between mode intensities in free-space and various in situ positions of a microwave oven. The lowest morphology-dependent resonance—a magnetic dipolar mode—is experimentally confirmed, appearing at the predicted diameter of ∼1.35 cm. Finally, experimental evidence for higher order modes in larger spheres is suggestive but remains unresolved.
Principles, design and implementation of a direct AC-to-AC power converter—Regulated electronic transformer
Authors: Flaxer Eli
Published: November 2022

In the last three decades, the energy conversion market has been dominated by switching power converters due to reduction of size and cost of electronic components. This market includes four types of conversion: DC–DC, DC–AC, AC–DC, and AC–AC. While the first three types are applied directly in a single conversion, the AC–AC converter is comprised of two serial converters leading to an AC–DC–AC conversion. This article introduces, for the first time, a real direct single-stage AC–AC conversion electronic transformer. The single stage AC–AC converter is fabricated using a unique high efficiency topology, combined with the advantages of dual-stage power-quality protection. This single-stage AC–AC regulated electronic transformer is stabilized, controlled, protected, and can lock onto any line voltage (110 or 220 V) with a frequency of 45–65 Hz. Stabilization is achieved by fast pulse-width modulation technology, applied by two-way fast solid-state switches. The transformer is controlled by a 150 MHz digital signal processor and is fully protected against overcurrent and output short circuits. Our first stage transformer is a single-phase device with 5 kW power with an efficiency of better than 97% with one-tenth of the weight and volume of present conventional electromechanical transformers.
Comb-shaped Sb2S3 nanorod arrays on ZnO nanofibers for thin-film photovoltaics
Authors: Zhou Boyang , Sagawa Takashi
Published: November 2022

A hierarchical composite of Sb2S3 nanorods grown on zinc oxide (ZnO) nanofiber was prepared, and the formation of comb-shaped Sb2S3 nanorod arrays on the ZnO nanofibers was confirmed. It was found that the size of the diameter and the density of the nanorods are regulatable by changing the concentration of polyvinyl pyrrolidone as an additive for the growth of Sb2S3 nanorod on ZnO nanofiber. The obtained Sb2S3 nanorod arrays were applied as a light absorber for thin-film solar cells composed of glass-fluorine-doped tin oxide/compact ZnO/ZnO nanofibers−ZnS/Sb2S3 nanorod arrays/poly(3-hexylthiophene-2,5-diyl)/MoOx/Ag. The rectification ratio and photocurrent generation efficiency of the comb-shaped Sb2S3 nanorod arrays were improved as compared with the heterojunction of randomly stacked Sb2S3 nanorods. Smaller series resistance (Rs) of 8.13 Ω cm−2 and an ideality factor (n) of 2.84 with the comb-shaped Sb2S3 nanorod arrays than those of the randomly stacked ones of Rs = 15.01 Ω cm−2 and n = 3.83 also indicated superior charge extraction property and suppressed recombination of the comb-shaped Sb2S3 nanorod arrays at the interface.
Novel simulation of the time fractional Burgers–Fisher equations using a non-polynomial spline fractional continuity method
Authors: Yousif Majeed A. , Hamasalh Faraidun K.
Published: November 2022

In a recent study, we investigate the Burgers–Fisher equation through a developed scheme, namely, the non-polynomial spline fractional continuity method. The proposed models represent nonlinear optics, chemical physics, gas dynamics, and heat conduction. The basic concept of the new approach is constructing a non-polynomial spline with a fractional continuity equation instead of a natural derivative. Furthermore, the truncation error is analyzed to determine the order of convergence for the proposed scheme, and we presented theoretically the stability of the developed scheme using the von Neumann method. One might easily conclude that the new scheme is quite successful and effective in obtaining the numerical solutions of the time partial/fractional partial differential equations. In addition, we plotted contour, 2D, and 3D graphs for some reported solutions to compare the presented solution with an exact solution. The investigated method was tested in some examples and compared to previous solutions for showing the applicability and effectiveness of the developed numerical scheme. The absolute and norm errors L2 and L∞ has calculated to validate the accuracy and efficiency of the presented scheme. To our knowledge, all obtained solutions in this research paper are novel and not published beforehand.
An assessment of global ruminant methane-emission measurements shows bias relative to contributions of farmed species, populations and among continents
Authors: Della Rosa M. M. , Waghorn G. C. , Vibart R. E. , Jonker A.
Published: November 2022

Global ruminant methane (CH4)-mitigation strategies rely on data from in vivo CH4-emission measurements. This survey of 415 peer-reviewed studies of in vivo enteric-CH4 measurements from farmed ruminants details research objectives, diets, and methodology as well as groups within ruminant species. The survey results have been evaluated in relation to ruminant population data and the contributions of each species to CH4 emissions. Despite the highest estimated total CH4 emissions from ruminants in Asia, South America and Africa (accounting for 37%, 23% and 17% of total enteric-CH4 emissions respectively), the number of in vivo studies of CH4 measurements were 15%, 9% and 1% of global studies respectively. Globally, the most studied species were cattle (64%) and sheep (22%), whereas goats and buffalo accounted for 7% and 5% of studies respectively. These species account for 75%, 7%, 5% and 12% of total enteric-CH4 emissions respectively. Most cattle studies were with Bos taurus and only 12% of the cattle studies were with Bos indicus. Respiration chambers have been used in 51% of studies and, despite the development of other methodologies, they remain the dominant technique for measurement of enteric-CH4 production. Most studies involved animals fed high-forage diets; these were 56% of the studies with cattle, 73% with sheep, 47% for goats, but only 15% of studies with buffalo. The evaluation of diets as a mitigation strategy was the prime objective of all regions. The number of studies that have measured CH4 from cattle aligns with their contribution to enteric emissions; however, buffalo, Bos indicus cattle and mature beef cows were under-represented relative to their global populations and contribution to global emissions. Dominance of measurements from cattle was evident in all continents.
Historical ecology of semi-enclosed coastal embayments: tools and techniques for discovering ecological events of the recent past
Authors: Pedretti Yvette M. , Robson Belinda J.
Published: November 2022

The sheltered environments of coastal embayments have played a vital role for humans for millennia and their resources have underpinned modern industrial development globally. Their effective management and restoration remains an enormous challenge, owing, in part, to lack of recognition of the threshold changes that occurred in many bays prior to scientific study (i.e. >50 years ago). Advances in marine extraction technologies and increased clearing of catchments for agriculture and urbanisation in recent history (∼400 years) have resulted in profound physical, chemical and biological changes to these ecosystems. More recently, the integration of ecology, history, archaeology, economics and fisheries science have contributed to the emerging field of ‘marine historical ecology’ (MHE). The synthesis of information from these different disciplines can markedly improve knowledge of past ecosystem condition, thereby assisting managers to set realistic goals for environmental restoration to improve biodiversity and ecosystem function. This paper reviews historical knowledge of long-term environmental degradation processes in coastal embayments, summarising the wide range of methods and techniques used as evidence and providing examples from around the world, thereby illustrating the need for longer time-frames of reference for contemporary restoration ecology.
Prevalence of anti-hepatitis B core in men who have sex with men attending a sexual health clinic in Brighton, UK, from 2012 to 2019
Authors: Gouda Mahmoud , Fitzpatrick Colin , Williams Deborah , Richardson Daniel
Published: November 2022

Objective Hepatitis B is sexually transmitted among men who have sex with men (MSM) and has previously been endemic in some populations of MSM. Presence of anti-hepatitis B core (anti-HBc) determines previous or ongoing infection. We aimed to establish the prevalence and associations of anti-HBc in our clinic population of MSM. Method A cross-sectional study of newly attending MSM to determine the prevalence and associations of testing positive for anti-HBc using our clinic database from 2012 to 2019. We used crude odds ratios to identify any associations. Results There were 3342/5842 (58%) newly attending MSM who were tested for anti-HBc between 2012 and 2019. Of the 3342 MSM tested for anti-HBc, the median age was 30 years (interquartile range 23–43), 442 (13%) were living with HIV, 10 (0.3%) were HBsAg positive, 62 (1.9%) had past/current hepatitis C, 401 (12%) had a positive syphilis enzyme immunoassay (EIA), 455 (14%) were diagnosed with either gonorrhoea or chlamydia and 1080 (32%) were non-UK born. A total of 331 (10%, 95% confidence interval (CI) = 8.9–11.0) tested positive for anti-HBc and the proportion testing positive reduced significantly throughout the study period (P < 0.004). Testing positive for anti-HBc was associated with age >30 years (OR = 8.2, 95% CI = 5.9–11.4, P < 0.0001), having past/current hepatitis C (odds ratio (OR) = 5.0, 95% CI = 3.0–8.6, P < 0.0001), having a positive syphilis EIA (OR = 5.9, 95% CI = 4.4–7.3, P < 0.0001) and being non-UK born (OR = 1.4, 95% CI = 1.1–1.8, P < 0.006). There were no associations with HIV status or having a diagnosis of gonorrhoea or chlamydia. Conclusion Although reducing, the prevalence of anti-HBc remains endemic in MSM locally and further efforts are needed to enhance hepatitis B prevention strategies.
Recounting bias can affect abundance estimates from intensive helicopter surveys of feral goats
Authors: Tracey John P. , Fleming Peter J. S.
Published: November 2022

Context Aerial surveys are widely used for estimating the abundance of wildlife over large areas. The failure to count all animals within survey transects is commonly acknowledged and there are many techniques to measure and correct for underestimation. However, the possibility of animals being counted more than once in intensive surveys, which leads to overestimation, is rarely examined. Animals can move in response to observers or vehicles, and bias can occur when animals move before or after detection. Movement of animals immediately prior to and associated with observation processes is methodologically accommodated in distance sampling but bias attributable to responsive movement after observation platforms have passed requires investigation. Aims We sought to investigate potential biases caused by animal movement during intensive helicopter surveys of feral goats, and to quantify the probability that animals are available for recounting because of their responsive movements. Methods Using ground-based behavioural studies simultaneous with intensive helicopter strip surveys of feral goats, we measured the extent of responsive movement, distances and directions moved, and sampling design parameters, and contrasted those with random movements. Key results Feral goats did not move randomly in response to helicopters. Animals within the transect strips, and therefore potentially visible from the aircraft, were more likely to move than those outside the transect. Considerable responsive movement (flushing) occurred between transects and more animals (64%, n = 448) moved towards unsampled transects than towards transects already sampled. Because of the spatial separation of transects, 21% of goats were available for recounting in adjacent transects, leading to potential overestimation. Conclusions Although most extensive surveys of macropods and other wildlife in Australia account for overestimation in their design, surveys that sample intensively and apply valid corrections for undercounting are likely to produce positively biased estimates of abundance where flushing occurs. Likewise, intensive thermal surveys could be subject to positive bias for animals prone to flushing. This is routinely ignored in wildlife management and research where close transects are used to estimate abundance. Implications Responsive movement requires consideration when designing intensive aerial surveys of wildlife. Randomised transects without replacement or larger distances between transects will counteract recounting bias.
Learning to introduce referents in narration is resilient to the effects of late sign language exposure
Authors: Gür Cansu , Sümer Beyza
Published: November 2022

The present study investigates the effects of late sign language exposure on narrative development in Turkish Sign
Language (TİD) by focusing on the introductions of main characters and the linguistic strategies used in these introductions. We
study these domains by comparing narrations produced by native and late signers in TİD. The results of our study reveal that late
sign language exposure does not hinder the acquisition of linguistic devices to introduce main characters in narrations. Thus, their
acquisition seems to be resilient to the effects of late language exposure. Our study further suggests that a two-year exposure to
sign language facilitates the acquisition of these skills in signing children even in the case of late language exposure, thus
providing further support for the importance of sign language exposure to develop linguistic skills for signing children.
Intestinal toxicity to CTLA-4 blockade driven by IL-6 and myeloid infiltration
Authors: Zhou Yifan , Medik Yusra B. , Patel Bhakti , Zamler Daniel B. , Chen Sijie , Chapman Thomas , Schneider Sarah , Park Elizabeth M. , Babcock Rachel L. , Chrisikos Taylor T. , Kahn Laura M. , Dyevoich Allison M. , Pineda Josue E. , Wong Matthew C. , Mishra Aditya K. , Cass Samuel H. , Cogdill Alexandria P. , Johnson Daniel H. , Johnson Sarah B. , Wani Khalida , Ledesma Debora A. , Hudgens Courtney W. , Wang Jingjing , Wadud Khan Md Abdul , Peterson Christine B. , Joon Aron Y. , Peng Weiyi , Li Haiyan S. , Arora Reetakshi , Tang Ximing , Raso Maria Gabriela , Zhang Xuegong , Foo Wai Chin , Tetzlaff Michael T. , Diehl Gretchen E. , Clise-Dwyer Karen , Whitley Elizabeth M. , Gubin Matthew M. , Allison James P. , Hwu Patrick , Ajami Nadim J. , Diab Adi , Wargo Jennifer A. , Watowich Stephanie S.
Published: November 2022

Immune checkpoint blockade (ICB) has revolutionized cancer treatment, yet quality of life and continuation of therapy can be constrained by immune-related adverse events (irAEs). Limited understanding of irAE mechanisms hampers development of approaches to mitigate their damage. To address this, we examined whether mice gained sensitivity to anti-CTLA-4 (αCTLA-4)–mediated toxicity upon disruption of gut homeostatic immunity. We found αCTLA-4 drove increased inflammation and colonic tissue damage in mice with genetic predisposition to intestinal inflammation, acute gastrointestinal infection, transplantation with a dysbiotic fecal microbiome, or dextran sodium sulfate administration. We identified an immune signature of αCTLA-4–mediated irAEs, including colonic neutrophil accumulation and systemic interleukin-6 (IL-6) release. IL-6 blockade combined with antibiotic treatment reduced intestinal damage and improved αCTLA-4 therapeutic efficacy in inflammation-prone mice. Intestinal immune signatures were validated in biopsies from patients with ICB colitis. Our work provides new preclinical models of αCTLA-4 intestinal irAEs, mechanistic insights into irAE development, and potential approaches to enhance ICB efficacy while mitigating irAEs.
Wannier excitons confined in hexagonal boron nitride triangular quantum dots
Authors: Martins Quintela M F C , Peres N M R
Published: November 2022

With the ever-growing interest in quantum computing, understanding the behavior of excitons in monolayer quantum dots has become a topic of great relevance. In this paper, we consider a Wannier exciton confined in a triangular quantum dot of hexagonal boron nitride. We begin by outlining the adequate basis functions to describe a particle in a triangular enclosure, analyzing their degeneracy and symmetries. Afterwards, we discuss the excitonic Hamiltonian inside the quantum dot and study the influence of the quantum dot dimensions on the excitonic states.
Convolutive blind source separation in the frequency domain of mechanical noise for gas turbines based on bounded component analysis
Authors: Cheng Wei , Chen Shuang , Song Chao , Ou Kai , Chen Xuefeng , Wang Jun , Yan Liqi , Yang Mingsui
Published: November 2022

Noise source identification of gas turbines can provide the basis and guidance for vibration and noise reduction of gas turbines. Independent component analysis (ICA) is one of the most popular techniques for blind source separation (BSS) widely used in vibration and noise source separation in mechanical systems. ICA is suitable for independent source signals. However, in order to identify dependent mechanical noise sources in gas turbines, a convolutive BSS in the frequency domain based on bounded component analysis (BCA) is proposed. First, the basic theory of BSS and BCA is introduced in detail. The convolutive mixing in the time domain is transformed into an instantaneous mixing in the frequency domain by short time Fourier transform (STFT), and complex BCA is performed at each frequency bin. Second, a permutation alignment method based on local and global optimization is proposed to solve the problem of the permutation ambiguity. Finally, the accuracy and robustness of the proposed method are comparatively studied through typical numerical and experimental studies on a three-rotor experimental bench. The results show that the proposed method can effectively separate and identify independent and dependent source signals.
Acoustic suppressed topological refraction in valley sonic crystals
Authors: Wang Bing-bing , Jia Ding , Ge Yong , Yuan Shou-qi , Sun Hong-xiang
Published: November 2022

We report both experimentally and numerically that an acoustic suppressed topological refraction is realized by two kagome-lattice valley sonic crystals (VSCs). By simply rotating triangle rods in the VSCs, acoustic valley Hall phase transitions can be obtained. In a designed topological waveguide composed of two VSCs with distinct valley topological phases, two types of valley edge states can be observed in the domain wall. Furthermore, the topological waveguide can support a suppressed topological refraction of sound, which arises from the excitation of an acoustic dipole mode at the exit of the domain wall. Such a phenomenon is experimentally demonstrated by scanning topological refractions of the edge states from a zigzag termination, in which the theoretical prediction of a negative refraction almost overlaps with the perpendicular bisector of the dipole mode, and thus it is suppressed totally. Finally, the robustness of the suppressed topological refraction is demonstrated experimentally. Our work can find potential applications in designing the devices of robust directional sound transports and communications.
Near-infrared light emitting devices from Er doped silica thin films via introducing SnO2 nanocrystals
Authors: Wang LiXiang , Zhang YangYi , Chen JiaMing , Qu EnZe , Zhao JingJie , Li Dongke , Li Wei , Xu Jun , Chen KunJi
Published: November 2022

To get high performance light emitting devices on Si platform with emission wavelength at 1.55 μm is a challenge for future Si-based opto-electronic integration chips. In this paper, we fabricated near-infrared light-emitting devices based on Er/SnO2 co-doped silica thin films. The introduction of SnO2 nanocrystals with controllable size and density not only contributes to the near-infrared light emission enhancement of Er3+ ions at 1.55 μm, but also provides an effective carrier transport channel to realize efficient and stable electro-luminescence. The corresponding devices exhibit an external quantum efficiency of 5.4% at near infrared light region and the power efficiency is about 1.52 × 10−3. Our present work lays a solid foundation for facilitating Si-based light source towards practical application in the field of optoelectronic interconnection.
Effect of trivalent rare earth doping in cadmium silicates hosts: a theoretical study
Authors: Freire Eduily Benvindo Vaz , Santos Anderson Lira de Sales , Bispo Giordano Frederico da Cunha , Macedo Zélia Soares , Jackson Robert A , Valerio Mário Ernesto Giroldo
Published: November 2022

The objective of the present work is to investigate the possibilities for extrinsic defects in the three cadmium silicate matrices, CdSiO3, Cd2SiO4 and Cd3SiO5 and understand the final geometry of the most energetically favourable defects, which are generators of the luminescence centres in the material. This analysis will be performed out through classical and static computer modelling, using the code GULP. A number different mechanisms were modelled and their related solid state reactions were devised allowing the energetic calculations for the incorporation of trivalent rare Earth ions (R3+) in these matrixes. The results demonstrated that the trivalent rare Earth ions are preferentially incorporated substitutional at Cd sites with cadmium vacancy being created in order to compensate charge unbalance. Careful investigations of the different distances and angles between the ions involved in the defects formation for CdSiO3 found that all investigated R3+ ions have the same lower energetic defect configuration. The lowest energetic costs were found for a configuration where the rare Earth ions and the accompanying vacancy are almost aligned with a distance of around 7 Å and an angle closer to 180°. These results predict a possible set of two dipoles caused by the position of the cadmium vacancy in defect. Cadmium vacancies were expected to be present in the cadmium silicate due to the low vapor pressure of CdO; however, no previous work was able to pre-establish the final geometric structure of the cadmium silicate matrix in the defective region that can modify the luminescent centres in the material. The study of a wide range of possibilities for the insertion of defects and the proposal for the final configuration of these defects is presented, in order to assist in the identification of the sources and the specific chracteristics of the luminescent emissions presented in cadmium silicates doped with R3+.
Rayleigh-Taylor instability of radiation pressure driven foils: 2D effects
Authors: Krishnan Nivedya , Yadav Mamta , Mandal S , Kumar Ashok
Published: November 2022

Rayleigh–Taylor instability of radiation pressure accelerated ultra-thin foils of different thickness profiles and initial curvature is investigated in two dimensions using numerical simulations. The convex curvature of the foil (when viewed from the rear side of the foil) provides radially inward motion to the off-axis ions countering the radial divergence due to the Gaussian intensity distribution of the laser. Nonuniform foils, having maximum thickness on laser axis have similar effect. When a small ripple is superimposed on the foil on the scale of laser wavelength, the radiation pressure acts nonuniformly on the microscopic scale and the perturbation grows as the foil moves. After a certain distance of travel, the foil crests turn into cusps and the phase of quasi mono-energy ion acceleration terminates. The planar foil with uniform laser has a strong growth of Rayleigh–Taylor instability (RTI). The foils with curvature and nonuniform thickness have marginally lower growth rate. However, under all circumstances, RTI is found to induce additional energy spread, in radiation pressure acceleration (RPA) of thin foils.
Quantum tunneling dynamics with robust reciprocity of Bose-Einstein condensate in a quadruple-well potential with synthetic gauge fields
Authors: Wang Lin , Xiao Ke-Wen , Wang Wen-Yuan , Dou Fu-Quan
Published: November 2022

Bose-Einstein condensation (BEC) trapped in quadruple-well potential with complex coupling provides a great useful platform in theoretical and experimental researches. Utilizing analytical and numerical methods, we investigate tunneling dynamics and the reciprocity of quantum transport of BEC in quadruple-well potential formed by the laser-assisted transition. According to the investigation, the tunneling dynamics of BEC in this system is independent of dissipation and complex coupling between wells caused by Raman coupling laser. By adjusting the coupling phase, the coherent destruction of tunneling can be observed. Meanwhile, this system provides an applicable proposal for reciprocal quantum switch by using the tunneling dynamics of BEC.
Evaluating the detection and trapping of small gas molecules on hydrogenated siligene
Authors: Villarreal-Franco L G , Fernandez-Escamilla H N , Paez-Ornelas J I , Ponce-Perez R , Quijano-Briones J J , Perez-Tijerina E G , Takeuchi Noboru , Guerrero-Sánchez J
Published: November 2022

The use of new two-dimensional systems to detect and capture organic molecules remains a vital research area. In this work, we have investigated, by first-principles calculations, the feasibility of using a hydrogenated siligene (HSiGeH) monolayer to detect and capture small gas molecules through a self-propagating reaction mechanism. We have studied the adsorption of formaldehyde (CH2O), acetylene (C2H2), and ethylene (C2H4) on an HSiGeH monolayer with an H-vacancy (including two situations: an H-vacancy on a Si or a Ge atom). In each case, the molecule chemisorbs at the H-vacancy, increasing the C–O or C–C bond lengths, indicating that double and triple bonds of the molecule are partially broken, resulting in unpaired electrons in one C atom of each molecule. We have found that the hydrogenated chemisorbed molecule -with a new H-vacancy formed on the surface- is the most energetically favorable configuration for each reaction. The viability of the reactions was analyzed by describing the minimum energy path (MEP) computed by the climbing image nudged elastic band method (CI-NEB). Our results show that the self-propagating reaction is viable except for one case, where the C2H4 chemisorbs on the monolayer with the H-vacancy on Ge. These results point toward the application of the HSiGeH monolayer as a possible system for novel gas-removal systems.
Modal analysis of silicon-on-insulator based rib waveguide using fully vectorial finite-difference mode solver
Authors: Kumari Shayna , Prince Shanthi
Published: November 2022

In order to interface optical integrated devices with external sources, an understanding of the modal characteristics of the optical waveguide is essential. The finite difference approach is utilized in this work to analyse a rib waveguide based on a silicon-on-insulator platform. A silicon device layer with thickness of 220 nm and a buried oxide with thickness of 2000 nm are considered. It is important to study the modal field distribution and parameters of the waveguide. The simulation results on the behaviour of modal parameters show that both effective refractive index and group index decrease with wavelength. The effective refractive index of the guided mode increases with rib width and slab thickness. It is also observed that energy is more confined in a deeply etched waveguide than in a shallow etched waveguide. Additionally, it is noted that the effective mode area and full-width half maximum increase with rib width and slab thickness.
Standard model effective field theory from on-shell amplitudes*
Authors: Ma Teng , Shu Jing , Xiao Ming-Lei
Published: November 2022

We present a general method of constructing unfactorizable on-shell amplitudes (amplitude basis) and build up their one-to-one correspondence to the independent and complete operator basis in effective field theory (EFT). We apply our method to the Standard Model EFT and identify the amplitude basis in dimensions 5 and 6, which correspond to the Weinberg operator and operators in the Warsaw basis, except for some linear combinations.
Analysis of Dynamic Characteristics of Hydraulic Driven System for Weight Bearing Lower Limb Exoskeleton
Authors: Su QiYing , Pei ZhongCai , Tang ZhiYong
Published: November 2022

A new kind of weight-bearing lower limb exoskeleton driven by hydraulic cylinder is designed, and its structural characteristics and driving principle are analysed. The mathematical model and control block diagram of the valve controlled unsymmetrical cylinder system for the controlled rotary joint are established. The effects of structural parameters such as servo valve bandwidth, load mass and hydraulic cylinder size on the dynamic characteristics of the system are studied, and the force tracking curve optimized by structural parameters is given to prove the correctness of the theoretical analysis of the system, which provides theoretical support for the design of the weight-bearing lower limb exoskeleton.
Thermal Analysis and Static Lubrication Performance Study of Liquid Metal Journal Bearing
Authors: Wang Haifeng , Wang Yazhen , Xu Zhaoxiang
Published: November 2022

The temperature distribution of liquid metal journal bearing system in X-ray tube of medical CT machine was simulated by using simulation software, and the working temperature of the herringbone groove liquid metal journal bearing was initially determined. On this basis, the lubricating properties of the liquid metal lubricant were analyzed. The lubrication model of herringbone groove liquid metal journal bearing with Galinstan liquid metal as lubricant was established, and the influence of herringbone groove structure parameters on the static lubrication performance of liquid metal journal bearings was analyzed. The results show that the Galinstan liquid metal has good high temperature stability and can act as a reliable lubricant in the high temperature working environment of the medical CT machine X-ray tube.
Study on Calibration of Medical Analgesia Pump
Authors: Wang Huijuan , Xiang Mengdie , Xie Chuandong , Xu Yang , Luo Han
Published: November 2022

The medical analgesia pump is a liquid infusion device that can maintain a stable concentration of drugs in the blood and achieve better analgesic treatment with fewer drugs. It generally allows the patient to self-press to add an additional infusion based on the ongoing infusion, known as patient-controlled analgesia (PCA). It makes the treatment more individualized and consistent with the large variation in pain sensation. It is very important to the analgesic effect and medical safety whether the infusion of medical analgesia pump is accurate and the flow rate is stable. However, the current standard testing methods of the pharmaceutical industry are only applicable to the laboratory testing of the medical analgesic pump in the factory inspection, and not applicable to the evaluation of the accuracy of the medical analgesia pump used in medical institutions. In this paper, an infusion pump quality analyzer was used to calibrate the constant speed and the additional PCA infusion of medical analgesia pump, which ensured the accuracy and reliability of analgesic drug infusion.
Dynamic modeling and simulation analysis of steel wire winding of reinforcement cage roll welder
Authors: Huang Pengliang , Zhang Dongmin , Xu Yincang
Published: November 2022

In view of the problem that the spiral reinforcement material plate is out of sync due to the rotation speed during the work of the reinforcement cage roll welding machine, the spiral reinforcement is broken or loose. By discretizing the steel wire into several micro segments, the dynamic model of steel wire winding based on ADAMS virtual prototype technology is established. By analyzing the motion relationship between the material disc and the flower disc in the roll welding machine, the functional relationship between the material disc speed and time is fitted, so as to realize the dynamic simulation of steel wire winding. By analyzing the stress condition of steel wire micro segments, the accuracy of the material disc fitting speed is verified, At the same time, it provides a basis for the automation transformation and detection control scheme of roll welding machine.
Design and test of a tree-climbing and pruning robot
Authors: Wu Jianping , Yang Xi , Gao Chong , Li Wenhui
Published: November 2022

In view of the problems of manual pruning, such as time-consuming, labor-intensive, low efficiency and low degree of automation, the structure and working principle of the robot for tree-climbing and pruning were studied. Finding the problems in the process of product design, analyzing and defining them, transforming them into the standard mode of solving problems, and using TRIZ theory according to the essence of contradictions to solve the contradictions one by one. The virtual prototype was created to carry out the interference analysis and kinematics simulation analysis of the whole machine. The robot for tree-climbing and pruning was designed by modular design method, which can automatically climb to a certain height to realize the function of pruning and cutting the top of the tree trunk. The duty cycle of the motor output is gradually adjusted by PID algorithm to make multiple motors work synchronously and keep the robot stable in the up-tree pruning process and down-tree process. The robot was made and tested. The experimental results show that the diameter of climbing trunk is 100 mm∼300 mm, and the climbing speed is 1 m/min. It can be used for tree-climbing, pruning lateral branches and cutting main trunks of high-straight trunk trees. It can be self-adaptively held, fall-resistant, obstacle-crossing, and manual operate to improve efficiency.
Finite Element Analysis and optimization design of sprinkler Truss Structure
Authors: Wang Changhu , Meng Weiyun , Wang Jianxiang , Min Xiangmei
Published: November 2022

This paper includes three sections. Truss structures have been widely applied in bridges and buildings due to their light weight, reasonable load-bearing, and high material utilization rate. For truss structures serving as load-bearing carriers, their structural strength should be guaranteed, and moreover, their economic performance should be considered. First, the finite element theory was introduced, and the computer-aided simulation analysis was performed by combining numerical analysis and finite element theory. Second, the truss structure of a sprinkler was subjected to a mechanical analysis, and its stability was explored with its maximum displacement and maximum stress as constraints. Finally, the truss structure was optimally designed until its stability, strength, and stiffness met relevant requirements.
A Method of Connecting Traditional Energy-Consuming Equipment to the Internet of Things
Authors: Li Bingchen , Xiong Lei , Jin Zhongwen , Wang Jie , Tian Haoyu
Published: November 2022

The concept of the Internet of things affects the way that people control electrical appliances. Moreover, due to the increasing importance of energy saving, the transformation of electrical power and energy system (EPES) is urgently needed. However, massive waste of energy caused by the inappropriate use of power-consuming equipment and most of the electrical devices controlled in traditional methods. This paper illustrates an Internet of Things (IoT) and edge computing (EC) technique to intellectualize standard energy-consuming equipment via LoRa wireless technology. The proposed system is low power and supports ad-hoc networks. Each node connects to the Internet via a LoRa based gateway. We mainly focus on controlling regular air conditioning and lighting system in office buildings via web pages, apps, etc. To simplify the process of installing the purposed node, several techniques were used to take over the control of traditional power-consuming equipment via user-side. The EC node can receive the short control command and operate itself according to the environment sensing results without control intelligence from cloud server. The experimental results indicate that our intellectualized network can work reliably and save energy-consuming equipment from wasting power.
Paper Defect Detection Algorithm Based on the Mathematical Morphology and Computer Vision
Authors: Gao Zunhai , Qiu Yuzhan , Zhou Jicheng
Published: November 2022

A method for detecting paper’s surface defects is proposed, which is based on mathematical morphology algorithm and computer vision technique. Firstly, the mean filtering and wavelet denoising in image pre-processing are used to eliminate the image noise, and wavelet analysis can achieve image enhancement and increase the contrast between the target area and the background. And then, an improved threshold Canny operator is used to segment the image to extract the complete scratch line and other defect edges. Finally, the target region features are coloured by mathematical morphology processing. The method’s stimulating result is verified in the Matlab software, from which we can conclude that the method’s detecting effect is very effective.
Using an Improved Artificial Hummingbird Algorithm for Vision-Guided Optimization And Grasping of Multi-Objective Robots
Authors: Yang Rui , Zhou Qian , Mo Qinglong , Gan Lin , Hu Ruihan
Published: November 2022

AHA (artificial hummingbird algorithm) is a meta-heuristic optimization algorithm that simulates the unique flight and feeding patterns of hummingbirds. By combining the excellent strategy of the artificial hummingbird algorithm with the framework of the multi-objective optimization algorithm, the multi-objective artificial hummingbird algorithm is created, improved, and further enhanced. Therefore, the research on vision-guided optimization and grasping control of multi-objective robots based on an enhanced artificial hummingbird algorithm has significant academic significance and vast potential for application.