bluuebunny/crossref_metadata_2025 huggingface dataset:
Resultados do manejo de fraturas do rádio distal nos últimos 5 anos: metanálise de ensaios clínicos controlados e randomizados
Authors: Asmara Anak Agung Gede Yuda , Karna Made Bramantya , Meregawa Putu Feryawan , Deslivia Maria Florencia
Published: December 2022

Objetivo Nas últimas décadas, a placa volar bloqueada (PVB) tem sido o tratamento principal para fraturas do rádio distal (FRDs). Com o crescente conjunto de evidências, revisamos sistematicamente estudos sobre modificações recentes na PVB.

Métodos Uma pesquisa sistemática foi realizada utilizando o banco de dados PubMed/MEDLINE por estudos publicados em inglês nos últimos cinco anos. Os critérios de inclusão foram ensaios clínicos controlados e randomizados (ECCRs) sobre o tratamento cirúrgico de FRDs. Excluímos ensaios e estudos em andamento que não abordavam diretamente a FRD. Os desfechos primários avaliados foram desfechos clínicos subjetivos (como as pontuações no questionário de Deficiências do Braço, Ombro e Mão [Disabilities of the Arm, Shoulder and Hand, DASH, em inglês], na Avaliação do Punho Classificada pelo Paciente [Patient-rated Wrist Evaluation, PRWE, em inglês], no questionário Qualidade de Vida Europeia – 5 Dimensões [European Quality of Life–5 Dimensions, EQ-5D, em inglês], na Pesquisa de Saúde por Formulário Curto de 36 Itens [36-item Short Form Health Survey, SF-36, em inglês], e na Escala Visual Analógica [EVA]) e objetivos (taxa de complicações).

Resultados Identificamos 29 artigos publicados entre 2016 e 2020 com alta qualidade de evidência, exceto por um, de qualidade moderada. Ao todo, foram analisadas 3.079 FRDs neste estudo, Todos os estudos analisados, exceto por um, tinham maior proporção de participantes do gênero feminino, e somente em 1 estudo a idade média da amostra foi < 40 anos. Não houve diferença significativa entre a PVB e fixação externa (FE) em termos das pontuações no DASH (p = 0,18) e na PRWE (p = 0,77). Os resultados da PVB isolada, sem qualquer reparo do pronador quadrado (PQ), foram significativamente melhores.

Conclusão Em fraturas instáveis, a PVB e a FE produziram resultados comparáveis no longo prazo. Não há um benefício claro em se adicionar reparo do PQ à técnica cirúrgica atual da PVB.

Nível de Evidência Nível I
Frozen Elephant Trunk Sizing: A 30,000-Feet Perspective with Thoraflex Hybrid Stent Graft
Authors: Tan Sven Z. C. P. , Mohammed Idhrees , Bashir Mohamad
Published: December 2022

There is currently no standard, evidence-based approach for sizing the Thoraflex Hybrid prosthesis in frozen elephant trunk surgery. We present regional data on 906 Thoraflex grafts implanted in the United Kingdom between December 2012 and August 2021 to emphasize the heterogeneity in sizing practices and evaluate the impact this may have on clinical outcomes. Highlighting this heterogeneity will help develop an evidence-based approach to prosthesis sizing, thereby aiding decision-making for arch repair.
Alveolar Bone Loss in Diabetic Patients: A Case–Control Study
Authors: Tabassum Afsheen
Published: December 2022

Objectives Based on literature, very few case–control studies have been executed to confirm the relationship between diabetes mellitus and the severity of mean alveolar bone loss. Therefore, the aim was to assess the differences in mean alveolar bone loss among diabetic (type 2) and nondiabetic patients in the Saudi population.

Materials and Methods Nine-hundred eighty-two patient records were seen in this retrospective study. Patient demographic data and medical records were examined. The mean alveolar bone loss was measured in posterior teeth by calculating the distance from the base of cementoenamel junction to the alveolar crest using the bitewing radiographs. SPSS 20.0 was used for data analysis. An unpaired t-test was utilized to analyze the mean alveolar bone loss across multiple variables. p-Value less than or equal to 0.05 was contemplated as significant.

Results The overall mean alveolar bone loss for all 124 patients was 2.83 ± 1.13 mm. Diabetic patients had greater mean alveolar bone loss measured in millimeters than nondiabetic patients (3.07 ± 1.14mm vs. 2.59 ± 1.08mm, respectively), and the difference was significant (p = 0.018). In terms of the severity of mean alveolar bone loss, diabetic patients experience statistically higher mean alveolar bone loss as compared with nondiabetic patients.

Conclusion In our study population, the overall mean alveolar bone loss prevalence was greater in diabetes patients than in nondiabetic individuals. According to the severity of bone loss, the distribution of moderate and severe periodontitis was higher in diabetic patients. To enhance patients' quality of life, the awareness and education among patients regarding the association among diabetes mellitus and oral health, particularly periodontal disease, should be promoted.
Prevalence, Clinical Characteristics, and Treatment Response in Patients with Post Cricoid Inlet Patch—A Descriptive Retrospective Study
Authors: Ali Irshad H. , Bale Abhijith , Jalihal Umesh , C. Praveen Kumar A. , Bale Ajay , Sreenath Meghana
Published: December 2022

Objectives The aim of this study was to determine the incidence of post cricoid inlet patch (PC-IP) and to assess the clinical characteristics, pathological features, and treatment response.

Materials and Methods A retrospective cross-sectional study was conducted from April 2016 to April 2021 in the tertiary gastroenterology unit of urban India. All patients with symptoms of globus sensation, chronic cough, heartburn, hoarseness, throat pain, dysphagia, and acid regurgitation after a thorough clinical examination underwent esophagogastroduodenoscopy by experienced endoscopists including biopsy. Sociodemographic data, symptoms and its duration, previous hospital visits, and chronic proton pump inhibitor (PPI) use were noted during the study.

Results  Three-thousand two-hundred fifty upper gastrointestinal endoscopies were performed during the study period. The prevalence of PC-IP was 2.7%, comprising 36.3% males and rest females. Mean age was 36.2 ± 17years. The most common symptom among these patients was globus sensation (81.8%) followed by acid regurgitation (75%), dyspepsia (64.7%), dysphagia (48.8%), throat pain (29.54%), chronic cough (22.72%), hoarseness (22.72%), and others (6.81%). Mean diameter of PC-IP was 1.5 ± 0.5 cm, more than one patch was found in 23.76% of patients. Histopathological examination showed heterotrophic gastric mucosa in 77.27%, out of which 38.23% had oxyntic type, 44.11% had mucoid type, and the rest had mixed cell type. On median follow-up after 20 months, 68.18% of patient had persistent symptoms, 77.27% were PPI responsive, and 22.73% were PPI refractory. On follow-up, 38.63% of patients had a repeat endoscopic procedure and biopsy (20.45%); none showed any changes in size or dysplasia.

Conclusion Prevalence of PC-IP could be higher than the estimated. Careful examination of upper esophagus and use of narrow band imaging will increase the possibility of identifying IP. Those symptomatic patients need treatment with PPI, sometimes for long term. Ablative therapy with radiofrequency or argon plasma coagulation needs further clarification.
Recent Advances in Intrahepatic Biliary Epithelial Heterogeneity
Authors: Little Ashleigh , Medford Abigail , O'Brien April , Childs Jonathan , Pan Sharon , Machado Jolaine , Chakraborty Sanjukta , Glaser Shannon
Published: December 2022

Biliary epithelium (i.e., cholangiocytes) is a heterogeneous population of epithelial cells in the liver, which line small and large bile ducts and have individual responses and functions dependent on size and location in the biliary tract. We discuss the recent findings showing that the intrahepatic biliary tree is heterogeneous regarding (1) morphology and function, (2) hormone expression and signaling (3), response to injury, and (4) roles in liver regeneration. This review overviews the significant characteristics and differences of the small and large cholangiocytes. Briefly, it outlines the in vitro and in vivo models used in the heterogeneity evaluation. In conclusion, future studies addressing biliary heterogeneity's role in the pathogenesis of liver diseases characterized by ductular reaction may reveal novel therapeutic approaches.
Perovskite photonic crystal photoelectric devices
Authors: Ji Yanan , Xu Wen , Rasskazov Ilia L. , Liu Haichun , Hu Junhua , Liu Mao , Zhou Donglei , Bai Xue , Ågren Hans , Song Hongwei
Published: December 2022

Metal halide perovskite materials have been extensively explored in modern photonic devices. Photonic crystals (PCs) are periodic structures with specific optical properties, such as photonic stop bands and “slow photon” effects, which can tailor the propagation and distribution of photons in photoelectric devices. PCs have in recent years been widely explored to significantly improve the performance of perovskite luminescent materials and/or photoelectric devices. Therefore, a full understanding of the key role of PCs and a further learning of the correct use of PCs in perovskite photonic/photoelectric devices are essential for realizing the inherent potential of the superior performance of such devices. By means of this first review, we aim at offering a comprehensive framework description for PCs suitable for high-performance perovskite photoelectric devices. We start with a brief introduction to the basic aspects of PCs. Then, we summarize the influences of PCs on emission/absorption for perovskite luminescent materials. Subsequently, we systematically discuss concepts like light extraction, light trapping, slow-light effects, and structural effects of PCs for perovskite devices, with a particular emphasis on their theoretical descriptions. We argue that the marriage of perovskite materials with PCs can open up a novel frontier in photoelectric devices that potentially can spawn many exciting new fields.
The Mediterranean diet and One Health: A study in synergies
Authors: Tangredi Basil P.
Published: December 2022

Food consumption patterns (diets) lie at the nexus of human wellness and environmental conservation. The Mediterranean diet, the traditional food and lifestyle patterns of the Mediterranean populations, is a plant-based whole foods cultural model of a healthy diet. The environmental benefits are rooted in the agro-silvo-pastoral farming systems promoting sustainable productivity, and conserving biodiversity and water resources, while also decreasing greenhouse gas emissions and future land clearing. Pasture-based husbandry results in improved animal health and welfare. Understanding the ancient hierarchy of synergies in this complex system can aid policy-makers, public health planners, agriculturists, and animal advocates meet present and future challenges.

One Health Impact Statement

Food choice can have a profound effect on human health and the environment. Less obvious is the impact on the health and welfare of food-producing animals. The Mediterranean dietary and lifestyle pattern is a plant-based whole foods diet, arising from sustainable agroecological practices, resulting in tangible benefits in all three domains. The synergistic aspects of each domain assemble into a complex system exemplifying the interdisciplinary concept of One Health that is crucial to meeting the challenges of today.
Innovative trends in reducing food waste and ensuring a more sustainable food system and environment
Authors: Areche Franklin Ore , Gondal Aqarab Husnain , Landeo Oliver Taype , Flores Denis Dante Corilla , Rodríguez Alfonso Ruiz , Pérez Peter Llimpe , Huaman Jovencio Ticsihua , Roman Almer Ventura , Correo Rafael Julian Malpartida Yapias
Published: December 2022

Food waste is one of the most important issues affecting modern food systems, with estimates indicating that almost one-third of food is either lost or wasted throughout the food supply chain, resulting in substantial environmental and socioeconomic consequences. We generate tonnes of edible and non-food wastes each year that is lost through inadequate storage or transportation, improper handling, adverse weather conditions, customer behaviour, a lack of cold storage or rejection in relation to aesthetic standards. Reduction in food loss and waste may result in more food for everyone, lower greenhouse gas emissions, less strain on water and land resources, higher productivity, economic development and more sustainable communities. This can be attained by adopting green, digital, innovative and enhanced technologies that are increasingly being used to prevent, reuse and recycle food waste. It has also been explored briefly how food waste might be recycled, waste minimised at source by technological options including machine learning etc. and utilised as a source of energy, biofuels, and nutrients in the agricultural industry. The present study discusses the technological advancement in nanotechnology, digital and green extraction technologies that are promising in the battle to decrease food waste and increase food security. It also explores the digital innovations in novel apps, platforms, social media for preventing and monitoring food waste and loss to raise public awareness. Finally, proposals for reducing waste through public awareness and necessary measures for governments are also presented.
Successful hospitality micro-entrepreneurs in Bandung, Indonesia
Authors: Abdullah Taufik , Carr Neil , Lee Craig
Published: December 2022

This case study investigates factors that contribute to the success of street food vendors based on interviews with vendors in Bandung, Indonesia. The study found that success for street food vendors is not exclusively related to gaining more financial and/or material possessions. Success can also be related to their business, individual and family well-being, and contribution to the community. The findings also show that achieving success for street food vendors can be attributed to several factors: networks, product and service quality, positive attitudes, and the utilization of technology.
A comprehensive review of various non-cyanide electroplating baths for the production of silver and gold coatings
Authors: Satpathy Bangmaya , Jena Sambedan , Das Siddhartha , Das Karabi
Published: December 2022

Cyanide-based baths are generally used industrially to produce silver and gold coatings via electroplating. Baths containing ([Au(CN)2]−) and ([Ag(CN)2]−) are used for the deposition of gold and silver coatings, respectively. However, due to the severe toxicity, the technical personnel involved in work are at risk. Additionally, the disposal of cyanide-containing wastes poses a significant threat to the environment as they pollute various natural resources. The coatings produced from alkaline cyanide-based baths cause embrittlement of electronic circuit patterns. Due to these reasons, many cyanide-free baths have started to replace the existing cyanide-based baths. In the cyanide-free baths, the primary cyanide complexing agent is replaced with eco-friendly alternative compounds like sulphite, thiosulphate, thiourea, DMH, EDTA, and ionic liquids (ILs). This review article provides an overview of the various cyanide-free electroplating baths available for electroplating silver and gold that are either used for commercial practice or are developed for laboratory-scale use.
Gating and modulation of an inward-rectifier potassium channel
Authors: Jogini Vishwanath , Jensen Morten Ø. , Shaw David E.
Published: December 2022

Inward-rectifier potassium channels (Kirs) are lipid-gated ion channels that differ from other K+ channels in that they allow K+ ions to flow more easily into, rather than out of, the cell. Inward rectification is known to result from endogenous magnesium ions or polyamines (e.g., spermine) binding to Kirs, resulting in a block of outward potassium currents, but questions remain regarding the structural and dynamic basis of the rectification process and lipid-dependent channel activation. Here, we present the results of long-timescale molecular dynamics simulations starting from a crystal structure of phosphatidylinositol 4,5-bisphosphate (PIP2)-bound chicken Kir2.2 with a non-conducting pore. After introducing a mutation (G178R) that is known to increase the open probability of a homologous channel, we were able to observe transitions to a stably open, ion-conducting pore, during which key conformational changes occurred in the main activation gate and the cytoplasmic domain. PIP2 binding appeared to increase stability of the pore in its open and conducting state, as PIP2 removal resulted in pore closure, with a median closure time about half of that with PIP2 present. To investigate structural details of inward rectification, we simulated spermine binding to and unbinding from the open pore conformation at positive and negative voltages, respectively, and identified a spermine-binding site located near a previously hypothesized site between the pore cavity and the selectivity filter. We also studied the effects of long-range electrostatics on conduction and spermine binding by mutating charged residues in the cytoplasmic domain and found that a finely tuned charge density, arising from basic and acidic residues within the cytoplasmic domain, modulated conduction and rectification.
Wronskian structures of planar symplectic ensembles
Authors: Byun Sung-Soo , Ebke Markus , Seo Seong-Mi
Published: December 2022

We consider the eigenvalues of non-Hermitian random matrices in the symmetry class of the symplectic Ginibre ensemble, which are known to form a Pfaffian point process in the plane. It was recently discovered that the limiting correlation kernel of the symplectic Ginibre ensemble in the vicinity of the real line can be expressed in a unified form of a Wronskian. We derive scaling limits for variations of the symplectic Ginibre ensemble and obtain such Wronskian structures for the associated universality classes. These include almost-Hermitian bulk/edge scaling limits of the elliptic symplectic Ginibre ensemble and edge scaling limits of the symplectic Ginibre ensemble with boundary confinement. Our proofs follow from the generalised Christoffel–Darboux formula for the former and from the Laplace method for the latter. Based on such a unified integrable structure of Wronskian form, we also provide an intimate relation between the function in the argument of the Wronskian in the symplectic symmetry class and the kernel in the complex symmetry class which form determinantal point processes in the plane.
Multi-step phase transitions and gravitational waves in the inert doublet model
Authors: Benincasa Nico , Delle Rose Luigi , Kannike Kristjan , Marzola Luca
Published: December 2022

The inert doublet model is a well-motivated extension of the Standard Model that contains a dark matter candidate and modifies the dynamics of the electroweak symmetry breaking. In order to detail its phenomenology, we perform a comprehensive study of cosmic phase transitions and gravitational wave signals implied by the framework, accounting for the latest results of collider experiments. We require the neutral inert scalar to constitute, at least, a subdominant part of the observed dark matter abundance. While most of the phase transitions proceed through a single step, we identify regions of the parameter space where the electroweak vacuum is reached after multiple phase transitions. The resulting gravitational wave spectrum is generally dominated by single-step transitions and, in part of the parameter space, falls within the reach of future gravitational wave detectors such as LISA, BBO or DECIGO. We find that direct detection experiments efficiently probe the part of parameter space associated with multi-step phase transitions, which remain unconstrained only in the Higgs resonance region testable with future monojet searches. The implications of the new determination of theWboson mass are also discussed.
On the complete weight distributions of quantum error-correcting codes
Authors: Du Chao , Ma Zhi , Xiong Maosheng
Published: December 2022

In a recent paper, Hu et al. defined the complete weight distributions of quantum codes and proved the MacWilliams identities, and as applications they showed how such weight distributions may be used to obtain the singleton-type and hamming-type bounds for asymmetric quantum codes. In this paper we extend their study much further and obtain several new results concerning the complete weight distributions of quantum codes and applications. In particular, we provide a new proof of the MacWilliams identities of the complete weight distributions of quantum codes. We obtain new information about the weight distributions of quantum MDS codes and the double weight distribution of asymmetric quantum MDS codes. We get new identities involving the complete weight distributions of two different quantum codes. We estimate the complete weight distributions of quantum codes under special conditions and show that quantum BCH codes by the Hermitian construction from primitive, narrow-sense BCH codes satisfy these conditions and hence these estimate applies.
Improved quantum (t, n) threshold group signature
Authors: Zhang Yaodong , Liu Feng , Zuo Haixin
Published: December 2022

Threshold signature is an important branch of the digital signature scheme, which can distribute signature rights and avoid the abuse of signature rights. With the continuous development of quantum computation and quantum information, quantum threshold signatures are gradually becoming more popular. Recently, a quantum (t, n) threshold group signature scheme was analyzed that uses techniques such as quantum-controlled-not operation and quantum teleportation. However, this scheme cannot resist forgery attack and does not conform to the design of a threshold signature in the signing phase. Based on the original scheme, we propose an improved quantum (t, n) threshold signature scheme using quantum (t, n) threshold secret sharing technology. The analysis proves that the improved scheme can resist forgery attack and collusion attack, and it is undeniable. At the same time, this scheme reduces the level of trust in the arbitrator during the signature phase.
Identifying multiple influential spreaders in complex networks based on spectral graph theory
Authors: Cui Dong-Xu , He Jia-Lin , Xiao Zi-Fei , Ren Wei-Ping
Published: December 2022

One of the hot research topics in propagation dynamics is identifying a set of critical nodes that can influence maximization in a complex network. The importance and dispersion of critical nodes among them are both vital factors that can influence maximization. We therefore propose a multiple influential spreaders identification algorithm based on spectral graph theory. This algorithm first quantifies the role played by the local structure of nodes in the propagation process, then classifies the nodes based on the eigenvectors of the Laplace matrix, and finally selects a set of critical nodes by the constraint that nodes in the same class are not adjacent to each other while different classes of nodes can be adjacent to each other. Experimental results on real and synthetic networks show that our algorithm outperforms the state-of-the-art and classical algorithms in the SIR model.
Commensurate and incommensurate Haldane phases for a spin-1 bilinear–biquadratic model
Authors: Dai Yan-Wei , Chen Ai-Min , Liu Xi-Jing , Su Yao-Heng
Published: December 2022

Commensurate and incommensurate Haldane phases for a spin-1 bilinear-biquadratic model are investigated using an infinite matrix product state algorithm. The bipartite entanglement entropy can detect a transition point between the two phases. In both phases, the entanglement spectrum shows double degeneracy. We calculate the nonlocal order parameter of the bond-centered inversion in both phases, which rapidly approaches a saturation value of −1 as the segment length increases. The nonlocal order parameter of the bond-centered inversion with a saturation value −1 and the nonzero value string order indicate that the Haldane phase is a symmetry-protected topological phase. To distinguish the commensurate and incommensurate Haldane phases, the transversal spin correlation and corresponding momentum distribution of the structure factor are analyzed. As a result, the transversal spin correlations exhibit different decay forms in both phases.
Quantum homomorphic broadcast multi-signature based on homomorphic aggregation
Authors: Xu Xin , Yin Ai-Han
Published: December 2022

Quantum multi-signature has attracted extensive attention since it was put forward. Beside its own improvement, related research is often combined with other quantum signature. However, this type of quantum signature has one thing in common, that is, the generation and verification of signature depend heavily on the shared classical secret key. In order to increase the reliability of signature, the homomorphic aggregation technique is applied to quantum multi-signature, and then we propose a quantum homomorphic multi-signature protocol. Unlike previous quantum multi-signature protocols, this protocol utilizes homomorphic properties to complete signature generation and verification. In the signature generation phase, entanglement swapping is introduced, so that the individual signatures of multiple users are aggregated into a new multi-signature. The original quantum state is signed by the shared secret key to realize the verification of the signature in the verification phase. The signature process satisfies the homomorphic property, which can improve the reliability of the signature.
Phase-coherence dynamics of frequency-comb emission via high-order harmonic generation in few-cycle pulse trains
Authors: Liang Chang-Tong , Zhang Jing-Jing , Li Peng-Cheng
Published: December 2022

Frequency-comb emission via high-order harmonic generation (HHG) provides an alternative method for the coherent vacuum ultraviolet (VUV) and extreme ultraviolet (XUV) radiation at ultrahigh repetition rates. In particular, the temporal and spectral features of the HHG were shown to carry profound insight into frequency-comb emission dynamics. Here we present an ab initio investigation of the temporal and spectral coherence of the frequency comb emitted in HHG of He atom driven by few-cycle pulse trains. We find that the emission of frequency combs features a destructive and constructive coherences caused by the phase interference of HHG, leading to suppression and enhancement of frequency-comb emission. The results reveal intriguing and substantially different nonlinear optical response behaviors for frequency-comb emission via HHG. The dynamical origin of frequency-comb emission is clarified by analyzing the phase coherence in HHG processes in detail. Our results provide fresh insight into the experimental realization of selective enhancement of frequency comb in the VUV–XUV regimes.
Diamond/c-BN van der Waals heterostructure with modulated electronic structures
Authors: Jia Su-Na , Li Gao-Xian , Gao Nan , Cheng Shao-Heng , Li Hong-Dong
Published: December 2022

The structural and electronic properties of (100), (110), and (111) diamond/cubic boron nitride (c-BN) heterostructures are systematically investigated by first principles calculation. The interface between diamond and c-BN shows the weak van der Waals interactions, which is confirmed by the interface distance and interface binding energy. The diamond/c-BN structures are the direct bandgap semiconductors with moderate bandgap values ranging from 0.647 eV to 2.948 eV. This work helps to promote the application of diamond in electronic and optoelectronic devices.
Experimental and numerical analyses of electrohydrodynamic force according to air pressure
Authors: Quan Rong-Hui , Wang Bo , Yao Yun-Jia
Published: December 2022

Electrohydrodynamic (EHD) force produced by corona discharge is considered as a new thrust for solar-powered aircraft and stratosphere balloons in near space. However, its performance at low air pressures remains to be clarified. An experiment of measuring the EHD force at 0.02 atm–1.0 atm (1 atm = 1.01325×105 Pa) is carried out with the wire-to-cylinder geometric structure. The ion distribution is analyzed by using the drift-diffusion model with two-dimensional numerical simulation. The experimental result shows that the EHD force is not linearly related to the corona discharge current at low air pressures. Numerical simulation finds that the proportion of ions in the counter-direction electric field increases from approximately 0.36% to 30% when the pressure drops from 1.0 atm to 0.2 atm. As a result, the EHD force with a constant power supply drops faster than the previous theoretical prediction in the ground experiment, suggesting that the consideration of counter-direction EHD force is necessary to improve the ionic wind propulsion efficiency in near-space applications.
Generalized uncertainty principle from long-range kernel effects: The case of the Hawking black hole temperature
Authors: El-Nabulsi Rami Ahmad , Anukool Waranont
Published: December 2022

We prove the existence of an analogy between spatial long-range interactions, which are of the convolution-type introduced in non-relativistic quantum mechanics, and the generalized uncertainty principle predicted from quantum gravity theories. As an illustration, black hole temperature effects are discussed. It is observed that for specific choices of the moment’s kernels, cold black holes may emerge in the theory.
Cascade excitation of vortex motion and reentrant superconductivity in flexible Nb thin films
Authors: Zhang Liping , Xu Zuyu , Li Xiaojie , Zhang Xu , Qin Mingyang , Zhang Ruozhou , Xu Juan , Cheng Wenxin , Yuan Jie , Wang Huabing , Silhanek Alejandro V. , Zhu Beiyi , Miao Jun , Jin Kui
Published: December 2022

High quality Nb films were successfully prepared on both flexible polyimide (PI) and rigid Al2O3 substrates and their transport properties were systematically studied at various applied currents, external magnetic fields, and sample orientations. It is found that a curved Nb/PI film exhibits quite different superconducting transition and vortex dynamics compared to the flat Nb/Al2O3 film. For the curved Nb/PI film, smooth superconducting transitions were obtained at low currents, while unexpected cascade structures were revealed in the ρ(T) curves at high currents. We attribute this phenomenon to the gradient distribution of vortex density together with a variation of superconductivity along the curved film. In addition, reentrant superconductivity was induced in the curved Nb/PI thin film by properly choosing the measurement conditions. We attribute this effect to the vortex pinning from both in-plane vortices and out-of-plane vortices. This work reveals the complex transport properties of curved superconducting thin films, providing important insights for further theoretical investigations and practical developments of flexible superconductors.
Demonstrate chiral spin currents with nontrivial interactions in superconducting quantum circuit
Authors: Yu Xiang-Min , Deng Xiang , Xu Jian-Wen , Zheng Wen , Lan Dong , Zhao Jie , Tan Xinsheng , Li Shao-Xiong , Yu Yang
Published: December 2022

Quantum many-body systems in which time-reversal symmetry is broken give rise to a wealth of exotic phases, and thus constitute one of the frontiers of modern condensed matter physics. Quantum simulation allows us to better understand many-body systems with huge Hilbert space, where classical simulation is usually inefficient. With superconducting quantum circuit as a platform for quantum simulation, we realize synthetic Abelian gauge fields by using microwave drive and tunable coupling in loop configurations to break the time-reversal symmetry of the system. Based on high-precision manipulation and readout of circuit-QED architecture, we demonstrate the chiral ground spin current of a time-reversal symmetry broken system with nontrivial interactions. Our work is a significant attempt to simulate quantum many-body systems with time-reversal symmetry breaking in multi-qubit superconducting processors.
Focused-ion-beam assisted technique for achieving high pressure by uniaxial-pressure devices
Authors: Liu Di , Wang Xingyu , Li Zezhong , Ma Xiaoyan , Li Shiliang
Published: December 2022

Uniaxial pressure or strain can introduce a symmetry-breaking distortion on the lattice and may alter the ground states of a material. Compared to hydrostatic pressure, a unique feature of the uniaxial-pressure measurements is that a tensile force can be applied and thus a “negative” pressure can be achieved. In doing so, both ends of the sample are usually glued on the frame of the uniaxial-pressure device. The maximum force that can be applied onto the sample is sometimes limited by the shear strength of the glue, the quality of the interface between the sample and the glue, etc. Here we use focused ion beam to reduce the width of the middle part of the sample, which can significantly increase the effective pressure applied on the sample. By applying this technique to a home-made piezobender-based uniaxial-pressure device, we can easily increase the effective pressure by one or two orders of magnitude as shown by the change of the superconducting transition temperature of an iron-based superconductor. Our method thus provides a possible way to increase the upper limit of the pressure for the uniaxial-pressure devices.
Superconductivity in epitaxially grown LaVO3/KTaO3(111) heterostructures
Authors: Liu Yuan , Liu Zhongran , Zhang Meng , Sun Yanqiu , Tian He , Xie Yanwu
Published: December 2022

Complex oxide heterointerfaces can host a rich of emergent phenomena, and epitaxial growth is usually at the heart of forming these interfaces. Recently, a strong crystalline-orientation-dependent two-dimensional superconductivity was discovered at interfaces between KTaO3 single-crystal substrates and films of other oxides. Unexpectedly, rare of these oxide films was epitaxially grown. Here, we report the existence of superconductivity in epitaxially grown LaVO3/KTaO3(111) heterostructures, with a superconducting transition temperature of ∼ 0.5 K. Meanwhile, no superconductivity was detected in the (001)- and (110)-orientated LaVO3/KTaO3 heterostructures down to 50 mK. Moreover, we find that for the LaVO3/KTaO3(111) interfaces to be conducting, an oxygen-deficient growth environment and a minimum LaVO3 thickness of ∼ 0.8 nm (∼ 2 unit cells) are needed.
Overview of the III International Conference on Metrological Support of Innovative Technologies – ICMSIT-III-2022
Authors: Antokhina Yu A , Ovodenko A A , Okrepilov V V , Kovalev I V , Voroshilova A A
Published: December 2022

The overview describes the main directions and results of the III International Conference “ICMSIT-III-2022” held in St. Petersburg on 3-5 March 2022. It gives the details about the participants and the proceedings. The anchor partner of Krasnoyarsk Science and Technology City Hall was St. Petersburg State University of Aerospace Instrumentation. A description of the main trends in modern innovative technologies, engineering and industrial physics as well as in the development of the third International Forum “Metrological Support of Innovative Technologies” by the St. Petersburg State University of Aerospace Instrumentation is given in the overview.
Features of the use of bronze alloys to produce elastic elements for various purposes
Authors: Yu Silaev M , Loparev D V , Aksenov A A , Krivonogova A S , Pushkov Yu L
Published: December 2022

The article presents the results of the study of indicators of the relaxation resistance of elastic elements made of bronze alloys. The issues of assessing the quality of the initial material and finished products from bronze alloys are considered. Comprehensive studies of the BrNHK bronze alloy for the manufacture of helical compression springs have been carried out. Prototypes were made, cyclic tests of helical compression springs made of BrNHK alloy were carried out. A comparative analysis of the results of an experimental study on the possibility of using the BrNHK bronze alloy as a material for the manufacture of springs is carried out. The questions of the influence of surface defects of the material on the quality of products and technological properties are considered.
Rehabilitation system of human micromotor capabilities: concept and design
Authors: Berro S M , Timofeev A N
Published: December 2022

Nowadays many modern prostheses hand are available on the market today, but they are still far from being able to completely replace the human hand. In addition, there are many factors that limit the ability to fully use the prostheses by individuals with hand disability caused by amputation or nerve damage. This article presents a new concept of hand disability rehabilitation means, which allows precise manipulation of the instrument and, thus, a system to facilitate the reintegration in the labour market. The operation of tool manipulation is divided into initial rough and final fine movement phases. At the initial phase, the prosthesis is freely transferred in the workspace of the user stump. the precise movement of the instrument at the final phase is performed by a micromanipulator built into the prosthesis and resting on a table or other environmental objects. An inverted system is possible, in which the manipulator is installed on the desktop, where then the prosthesis can rest or the targeted object is fixed on it, for example, assembly process. The manipulator is controlled either by the prosthesis socket or by an external device. In the latter case, the user carries out the control actions by various parts of the body or by voice. As an example of a possible implementation of this concept, the design of a prosthesis with an integrated three-degree manipulator carried on adaptive support is described. The support naturally adjusts to the comfortable height and orientation of the tool, then its braked. A computer model of speed-position control of the rehabilitation system is presented.
Behavior of dispersion-reinforced concrete under dynamic action
Authors: Nikolenko S D , Sazonova S A , Asminin V F , Mozgovoj N V , Zvyagina L N
Published: December 2022

The work of structures under alternating dynamic load has also been studied and modeled. Based on the results of experimental studies, a comparison was made of the work of dispersed-laminated structures under alternating dynamic action of high intensity with the work of reinforced concrete beam elements under similar influences. Dispersed concrete reinforcement changes the properties of the latter. The results of comparative experimental studies of cubes and prisms with different degrees of compression reinforcement are presented. The research results showed a significant effect of dispersed reinforcement on the operation of structures under the investigated influences and the feasibility of combined reinforcement of structures. The use of dispersed reinforcement in structures will improve their performance.
Monitoring of the kinetic regularities of wear of the inner surfaces of technological equipment made of structural steels
Authors: Gadalov V N , Vornacheva I V , Filonovich A V , Plyakin A S , Mazeev O V , Xalin A N
Published: December 2022

The reasons for failures of technological equipment made of structural steels of long-term operation in various environments and fields of application are considered. Investigations of the intensity of wear of equipment failures through the rate of damaging processes are presented. Modeling the processes of wear and tear of steel equipment, its failures was carried out using regression and correlation analyzes. The results of diagnostics are presented in accordance with the theoretical provisions of statistical analysis, experiment in the form of polynomial kinetic models of wear. The results of comparison of experimental and theoretical data on the wear rate for various types of equipment are also presented. The results of the normal distribution of the experimental values of the degree of wear for various types of equipment are shown, which is confirmed by the general uniformity of corrosion.
Distribution of chloride ions along the flight path of aircraft (Overview)
Authors: Laptev A B , Akhiyarov R J , Lapteva A A , Puzanov A I , Zagorskikh O A
Published: December 2022

Based on the analysis of the literature, the number of corrosive particles entering the aircraft engine with air has been determined. It is shown that the atmosphere of the continents has the smallest number of chlorides, their maximum content on the seashore, the troposphere above 10 km has a stable amount of aerosol particles. A method for estimating the chloride content has been developed to predict the rate of sulfide-oxide corrosion of parts of the hot TRD tract.
Investigation of the effect of ion implantation on tribotechnical characteristics of cast iron
Authors: Yu Usanova O , Ryazantseva A V , Kolishchak L M
Published: December 2022

The article presents studies of the tribotechnical characteristics of cast iron after various types of hardening. Samples (chemical composition of the obtained cast iron: C - 3.06%; Cu - 2.38%; Si - 2.2%; Mn - 0.75%; Cr - 0.32%; P - 0.18%; Ni - 0.1%; S - 0.05%, and Brinell hardness - 1.97-2.07 GPa) for wear tests were previously implanted with N+, B+, C+ ions, as well as TiN sputtering and carbonitration. The research was carried out on a friction machine making reciprocating motion along the counterbody. In the course of the work, the main tribotechnical characteristics of cast iron samples were analyzed in the initial state, after implantation, carbonitration and deposition of TiN. The surface morphology of cast iron samples was also studied using a scanning electron microscope in the initial state and after the above types of processing.
Assessment of the influence of moisture content in enclosing concrete structures on heat losses
Authors: Arkulis M B , Logunova O S , Savchenko Y I , Dubsky G A , Ryskuzhina I V
Published: December 2022

The purpose of the study is to determine the effect of wetting of internal surfaces of enclosing concrete structures on heat losses. Based on the experimental data earlier received by the authors, the increase in the value of heat losses under different conditions has been proved. The irreversible character of wetting of concrete in operating conditions at increased humidity has been experimentally proved. The multi-layer model of large-panel residential buildings and the theory of heat conduction at a constant value of the coefficient of heat conductivity inside the layer have been used in the studies. M250 concrete samples made by different manufacturers were chosen as the basic material for the research. Wetting was carried out in laboratory conditions, in a humid environment with a relative humidity of 100% with partial immersion in water at atmospheric pressure and temperature of 200C. The flux through each layer of a given thickness was estimated according to the Fourier law. According to the results of theoretical and experimental research, it was found that: the time of drying of concrete exceeds wetting time more than twice, therefore wetting process in conditions of ineffective ventilation becomes irreversible; when wetting only the internal layer of the building envelope increases heat losses by about 5%, and wetting of internal layer leads to wetting of intermediate layer of building envelope and increase heat losses by 25%.
Effect of UV irradiation on photoluminescence of Er3+ions in matrices of metal oxides and fluorides
Authors: Zharovov D A , Rudakova A V , Shurukhina A V , Kataeva G V , Ryabchuk V K
Published: December 2022

A comprehensive study of UV-irradiation of Er-activated solid luminophores on f-f-luminescence of Er3+ions in metal oxide (ZrO2, La2O3) and fluoride (LaF3, YF3) matrices has been carried out. Both increasing (LaF3, YF3), and decreasing (ZrO2, La2O3) of luminescent emission intensity under monochromatic excitation at 377 nm caused by UV irradiation of dispersed samples have been observed. A possible mechanism of the established effect is briefly discussed
Testing of silicone and composite materials under conditions of extreme deformation
Authors: Ya Minaev A
Published: December 2022

Samples of silicone and composite material are studied in various compression modes up to the limiting permissible deformation levels. In the first series of tests, changes in the elastoplastic properties during deformation of a silicone sample without fillers are studied. In the second series of tests, changes in the elastic-plastic properties of a soft composite sample with special fillers are researched. Depending on the various magnitude of deformation, changes in the elastic modules of the tested materials are defined and analyzed. Based on the constructed characteristics, the ranges of the linear and non-linear regions of the compared materials are developed. Changes in the shape under various compression modes and the destruction of the silicone sample at the limiting permissible deformation level are shown. Changes in the shape of a composite sample with magnetic particles are shown under various compression modes. The unique property of the studied material to self-healing after repeat tests for maximum load limits has been established.
Real-time vertical leveling based on GIS and CAD
Authors: Djumanov Jamolzhon , Khaitov Bafo
Published: December 2022

A method of vertical planning based on graphic-analytical methods for determining the line of the average slope of a flat curve line is proposed. The initial data (ID) for modeling the calculated surface are determined by means of the Google Earth program. On the basis of lines of longitudinal and transverse sections of the relief, a mid-level plane, hereinafter referred to as the “plane of relief”, is determined. By varying the plane of the relief, a balance of earthworks is achieved. Design and calculation work is carried out directly in the CAD systems.
Modeling of the heat conduction process in composite media
Authors: Perevoznikov Evgeniy , Rymkevich Pavel , Stepashkina Anna
Published: December 2022

In this work we proposed a two-channel model of heat conduction processes in composite media on the basis of the general transfer theory. The obtained system of equations can be reduced to both the generalized Fourier equation and the system of Cattaneo equations describing fast processes. The stability of the processes is considered. A system of equations for perturbations is obtained. The calculation of the perturbations’ spectrum is given depending on the parameters of the model. From this fact it follows that in a linear system the stationary process of heat conduction is stable with respect to any small perturbations. If we take into account nonlinearity even in the simplest cases it leads to the appearance of various instabilities and the excitation of heat waves.
Structure of the most unstable modes in anisotropic turbulence
Authors: Balonishnikov Alexander , Kruchkova Julia
Published: December 2022

Dynamics of most unstable modes from isotropic state is the topic of this paper considered. Initial conditions for these modes are given to be agreed with the well-known energy spectra of fully developed turbulence. The simplified equation for the small-scale velocity of incompressible fluid is applied. The simple shear turbulent flow is considered. The final expressions for Reynolds stresses, dissipation transfer should be averaged over the time of the energetic eddies turnover.