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Author Correction: ITO-free silicon-integrated perovskite electrochemical cell for light-emission and light-detection
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作者 Maria Baeva Dmitry Gets +8 位作者 Artem Polushkin Aleksandr Vorobyov Aleksandr Goltaev Vladimir Neplokh Alexey Mozharov Dmitry VKrasnikov Albert GNasibulin Ivan Mukhin Sergey Makarov 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第3期50-50,共1页
Correction to:Opto-Electronic Advances https://doi.org/10.29026/oea.2023.220154 published online 26 April 2023 After the publication of this article1,it was brought to our attention that calculations of the PeLEC devi... Correction to:Opto-Electronic Advances https://doi.org/10.29026/oea.2023.220154 published online 26 April 2023 After the publication of this article1,it was brought to our attention that calculations of the PeLEC device elec-troluminescent(EL)efficiency contained a mistake,leading to an inaccurate quantity value.The device’s maxim-um EL efficiency constitutes not‘~120 klm/W’but‘4.3 lm/W’instead.Correction details are listed below. 展开更多
关键词 value. PEROVSKITE LISTED
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Constructing Representative Collective Signature Protocols Using The GOST R34.10-1994 Standard
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2023年第1期1475-1491,共17页
The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema... The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema helps to create a unique digital signature that deputizes a collective of people representing different groups of signers and may also include personal signers.The advantage of the proposed collective signature is that it can be built based on most of the well-known difficult problems such as the factor analysis,the discrete logarithm and finding modulo roots of large prime numbers and the current digital signature standards of the United States and Russian Federation.In this paper,we use the discrete logarithmic problem on prime finite fields,which has been implemented in the GOST R34.10-1994 digital signature standard,to build the proposed collective signature protocols.These protocols help to create collective signatures:Guaranteed internal integrity and fixed size,independent of the number of members involved in forming the signature.The signature built in this study,consisting of 3 components(U,R,S),stores the information of all relevant signers in the U components,thus tracking the signer and against the“disclaim of liability”of the signer later is possible.The idea of hiding the signer’s public key is also applied in the proposed protocols.This makes it easy for the signing group representative to specify which members are authorized to participate in the signature creation process. 展开更多
关键词 Signing collective signing group discrete logarithm group signature collective signature GOST standards
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ITO-free silicon-integrated perovskite electrochemical cell for light-emission and light-detection
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作者 Maria Baeva Dmitry Gets +8 位作者 Artem Polushkin Aleksandr Vorobyov Aleksandr Goltaev Vladimir Neplokh Alexey Mozharov Dmitry VKrasnikov Albert GNasibulin Ivan Mukhin Sergey Makarov 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第9期45-58,共14页
Halide perovskite light-emitting electrochemical cells are a novel type of the perovskite optoelectronic devices that differs from the perovskite light-emitting diodes by a simple monolayered architecture.Here,we deve... Halide perovskite light-emitting electrochemical cells are a novel type of the perovskite optoelectronic devices that differs from the perovskite light-emitting diodes by a simple monolayered architecture.Here,we develop a perovskite electrochemical cell both for light emission and detection,where the active layer consists of a composite material made of halide perovskite microcrystals,polymer support matrix,and added mobile ions.The perovskite electrochemical cell of CsPbBr3:PEO:LiTFSI composition,emitting light at the wavelength of 523 nm,yields the luminance more than 7000 cd/m2 and electroluminescence efficiency of 4.3 lm/W.The device fabricated on a silicon substrate with transparent single-walled carbon nanotube film as a top contact exhibits 40%lower Joule heating compared to the perovskite optoelectronic devices fabricated on conventional ITO/glass substrates.Moreover,the device operates as a photodetector with a sensitivity up to 0.75 A/W,specific detectivity of 8.56×1011 Jones,and linear dynamic range of 48 dB.The technological potential of such a device is proven by demonstration of 24-pixel indicator display as well as by successful device miniaturization by creation of electroluminescent images with the smallest features less than 50μm. 展开更多
关键词 composite inorganic halide perovskite silicon single walled carbon nanotubes light-emitting electrochemical cell PHOTODETECTOR indicator display
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基于石墨烯的光学控制窄带太赫兹开关(英文) 被引量:2
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作者 GREBENCHUKOV Alexander N ZAITSEV Anton D KHODZITSKY Mikhail K 《中国光学》 EI CAS CSCD 北大核心 2018年第2期166-173,共8页
本文提出了一种光控太赫兹开关,该开关采用覆盖单层石墨烯的十字金属谐振器超表面。利用石墨烯表面电导率模型和有限元法计算了这种复合结构的光谱特性。模拟结果表明,在0.2 W/mm^2的光泵浦后,传输谱(调制深度为36.8%,Q-因子为250)出现... 本文提出了一种光控太赫兹开关,该开关采用覆盖单层石墨烯的十字金属谐振器超表面。利用石墨烯表面电导率模型和有限元法计算了这种复合结构的光谱特性。模拟结果表明,在0.2 W/mm^2的光泵浦后,传输谱(调制深度为36.8%,Q-因子为250)出现了窄带共振衰减现象。另外,这种衰减的调制深度可以通过改变泵浦强度微调节。因此,光学可调谐太赫兹开关的设计将有助于太赫兹通信应用的功能组件开发。 展开更多
关键词 太赫兹 石墨烯 光开关器件
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Intelligent metaphotonics empowered by machine learning 被引量:8
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作者 Sergey Krasikov Aaron Tranter +1 位作者 Andrey Bogdanov Yuri Kivshar 《Opto-Electronic Advances》 SCIE EI 2022年第3期1-24,共24页
In the recent years,a dramatic boost of the research is observed at the junction of photonics,machine learning and artifi-cial intelligence.A new methodology can be applied to the description of a variety of photonic ... In the recent years,a dramatic boost of the research is observed at the junction of photonics,machine learning and artifi-cial intelligence.A new methodology can be applied to the description of a variety of photonic systems including optical waveguides,nanoantennas,and metasurfaces.These novel approaches underpin the fundamental principles of light-matter interaction developed for a smart design of intelligent photonic devices.Artificial intelligence and machine learn-ing penetrate rapidly into the fundamental physics of light,and they provide effective tools for the study of the field of metaphotonics driven by optically induced electric and magnetic resonances.Here we overview the evaluation of meta-photonics induced by artificial intelligence and present a summary of the concepts of machine learning with some specif-ic examples developed and demonstrated for metasystems and metasurfaces. 展开更多
关键词 metaphotonics machine learning artificial intelligence
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Dirac operator on the sphere with attached wires
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作者 E N Grishanov D A Eremin +1 位作者 D A Ivanov I Yu Popov 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期335-338,共4页
An explicitly solvable model for tunnelling of relativistic spinless particles through a sphere is suggested. The model operator is constructed by an operator extensions theory method from the orthogonal sum of the Di... An explicitly solvable model for tunnelling of relativistic spinless particles through a sphere is suggested. The model operator is constructed by an operator extensions theory method from the orthogonal sum of the Dirac operators on a semiaxis and on the sphere. The transmission coefficient is obtained. The dependence of the transmission coefficient on the particle energy has a resonant character. One observes pairs of the Breit–Wigner and the Fano resonances. It correlates with the corresponding results for a non-relativistic particle. 展开更多
关键词 模型算子 狄拉克 球体 相对论粒子 Fano共振 透射系数 可解模型 自旋粒子
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Predictors of heart rhythm disturbances in hypertensive obese patients with obstructive sleep apnea
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作者 Lyudmila Sergeevna Korostovtseva Nadezhda Edvinovna Zvartau +2 位作者 Oxana Petrovna Rotar Yurii Vladimirovich Sviryaev Aleksandra Olegovna Konradi 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第9期553-562,共10页
Objective To assess the incidence and predictors of heart rhythm and conduction disturbances in hypertensive obese patients with andwithout obstructive sleep apnea (OSA). Methods This is an open, cohort, prospective... Objective To assess the incidence and predictors of heart rhythm and conduction disturbances in hypertensive obese patients with andwithout obstructive sleep apnea (OSA). Methods This is an open, cohort, prospective study. Out of 493 screened patients, we selected 279hypertensive, obese individuals without severe concomitant diseases: 75 patients without sleep-disordered breathing (non-SDB group), and204 patients with OSA (OSA group). At baseline, all patients underwent examination, including ECG, Holter ECG monitoring, and sleepstudy. During follow-up (on 3, 5, 7 and 10th years; phone calls once per 6 months), information about new events, changes in therapy and lifestyle was collected, diagnostic procedures were performed. As the endpoints, we registered significant heart rhythm and conduction disordersas following: atrial fibrillation (AF), ventricular tachycardia, atrioventricular block (AV) 2-3 degree, sinoatrial block, significant sinus pauses(〉 2000 ms), and the required pacemaker implantation. Results The median follow-up was 108 (67.5-120) months. The frequency of heartrhythm disorders was higher in OSA patients (29 cases, X^2= 5.5; P = 0.019) compared to the non-SDB patients (three cases; OR: 3.92, 95%CI: 1.16-13.29). AF was registered in 15 patients (n = 12 in OSA group; P = 0.77). Heart conduction disturbance developed in 16 patients,without an association with the rate of coronary artery disease onset. Regression analysis showed that only hypertension duration was anindependent predictor olAF (OR: 1.10, 95% CI: 1.04-1.16; P = 0.001). In case of heart conduction disturbances, apnea duration was thestrongest predictor (P = 0.002). Conclusions Hypertensive obese patients with OSA demonstrate 4-fold higher incidence of heart rhythmand conduction disturbances than subjects without SDB. Hypertension duration is an independent predictor for AF development, while sleepapneaJhypopnea duration is the main factor for heart conduction disorders onset in hypertensive obese patients with OSA. 展开更多
关键词 Atrial FIBRILLATION CARDIOVASCULAR MORBIDITY CARDIOVASCULAR prognosis Heart conduction disorder OBSTRUCTIVE sleep APNEA
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Anomalies in Young's modulus behavior after annealing in polycrystalline SmS
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作者 V.V.Kaminskii N.V.Sharenkova +2 位作者 G.A.Kamenskaya M.A.Grevtsev Yu.V.Lyubimova 《Journal of Semiconductors》 EI CAS CSCD 2021年第3期50-53,共4页
In this paper,the dependencies of Young's modulus and attenuation decrement on samarium sulfide polycrystals(SmS)under various annealing temperatures are studied by the piezoelectric ultrasonic composite oscillato... In this paper,the dependencies of Young's modulus and attenuation decrement on samarium sulfide polycrystals(SmS)under various annealing temperatures are studied by the piezoelectric ultrasonic composite oscillator technique at a frequency of 100 kHz in the temperature range of 80-300 K.A decrease in Young's modulus with an increase of the annealing temperature due to the texturing of the material was revealed.At the same time,attenuation peaks were observed at temperatures about 90 and 125 K,presumably due to Niblett-Wilks and Bordoni relaxations. 展开更多
关键词 SMS ultrasonic spectroscopy Young's modulus annealing in polycrystals Bordoni relaxations attenuation decrement
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葡萄糖浓度对THz频段血液光学特性的影响(英文)
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作者 GUSEV Sviatoslav Igorevich DEMCHENKO Petr S +2 位作者 CHERKASOVA Olga P FEDOROV Vyacheslav I KHODZITSKY Mikhail K 《中国光学》 EI CAS CSCD 北大核心 2018年第2期182-189,共8页
无创性血糖检测仍是糖尿病患者护理安全舒适的现实科学任务。本文研究了血糖光学特性与血糖浓度之间的相关性。用时域THz光谱研究了全血在0.3~0.5 THz频率范围内的透射谱。在注射胰岛素后的短时间内,由同一糖尿病患者产生了生物样品。... 无创性血糖检测仍是糖尿病患者护理安全舒适的现实科学任务。本文研究了血糖光学特性与血糖浓度之间的相关性。用时域THz光谱研究了全血在0.3~0.5 THz频率范围内的透射谱。在注射胰岛素后的短时间内,由同一糖尿病患者产生了生物样品。得到了血液光学特性的频散特性。基于频散,给出了血糖浓度与折射率和介电常数的关系式。这项工作是复杂研究的一部分,重点是无创葡萄糖测量技术的发展。记录血糖水平与血液光学参数之间的依赖关系,使得将来可以使用反射光谱技术进行无创血糖水平检测。 展开更多
关键词 光谱学 太赫兹 葡萄糖 糖尿病
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New Representative Collective Signatures Based on the Discrete Logarithm Problem
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2022年第10期783-799,共17页
The representative collective digital signature scheme allows the creation of a unique collective signature on document M that represents an entire signing community consisting of many individual signers and many diff... The representative collective digital signature scheme allows the creation of a unique collective signature on document M that represents an entire signing community consisting of many individual signers and many different signing groups,each signing group is represented by a group leader.On document M,a collective signature can be created using the representative digital signature scheme that represents an entire community consisting of individual signers and signing groups,each of which is represented by a group leader.The characteristic of this type of letter is that it consists of three elements(U,E,S),one of which(U)is used to store the information of all the signers who participated in the formation of the collective signature on document M.While storing this information is necessary to identify the signer and resolve disputes later,it greatly increases the size of signatures.This is considered a limitation of the collective signature representing 3 elements.In this paper,we propose and build a new type of collective signature,a collective signature representing 2 elements(E,S).In this case,the signature has been reduced in size,but it contains all the information needed to identify the signer and resolve disputes if necessary.To construct the approved group signature scheme,which is the basic scheme for the proposed representative collective signature schemes,we use the discrete logarithm problem on the prime finite field.At the end of this paper,we present the security analysis of the AGDS scheme and a performance evaluation of the proposed collective signature schemes. 展开更多
关键词 Elliptic curve signing group individual signer collective signature group signature
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New Collective Signatures Based on the Elliptic Curve Discrete Logarithm Problem
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2022年第10期595-610,共16页
There have been many digital signature schemes were developed based on the discrete logarithm problem on a finite field.In this study,we use the elliptic curve discrete logarithm problem to build new collective signat... There have been many digital signature schemes were developed based on the discrete logarithm problem on a finite field.In this study,we use the elliptic curve discrete logarithm problem to build new collective signature schemes.The cryptosystem on elliptic curve allows to generate digital signatures with the same level of security as other cryptosystems but with smaller keys.To extend practical applicability and enhance the security level of the group signature protocols,we propose two new types of collective digital signature schemes based on the discrete logarithm problem on the elliptic curve:i)the collective digital signature scheme shared by several signing groups and ii)the collective digital signature scheme shared by several signing groups and several individual signers.These two new types of collective signatures have combined the advantages of group digital signatures and collective digital signatures.These signatures have a fixed size and do not depend on the number of members participating in the creation of the final collective signature.One of the advantages of the proposed collective signature protocols is that they can be deployed on top of the available public key infrastructures. 展开更多
关键词 Elliptic curve signing group individual signer collective signature group signature
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Constructing Collective Signature Schemes Using Problem of Finding Roots Modulo
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2022年第7期1105-1122,共18页
Digital signature schemes are often built based on the difficulty of the discrete logarithm problems,of the problem of factor analysis,of the problem of finding the roots modulo of large primes or a combination of the... Digital signature schemes are often built based on the difficulty of the discrete logarithm problems,of the problem of factor analysis,of the problem of finding the roots modulo of large primes or a combination of the difficult problems mentioned above.In this paper,we use the new difficult problem,which is to find the wth root in the finite ground field GF(p)to build representative collective signature schemes,but the chosen modulo p has a special structure distinct p=Nt_(0)t_(1)t_(2)+1,where N is an even number and t_(0),t_(1),t_(2) are prime numbers of equal magnitude,about 80 bits.The characteristics of the proposed scheme are:i)The private key of each signer consists of 2 components(K_(1),K_(2)),randomly selected,but the public key has only one component(Y)calculated by the formula Y=K_(w)^(1)_(1) K^(w)_(2)^(2);w_(1)=t_(0)t_(1) and w_(2)=t_(0)t_(2);and ii)The generated signature consists of a set of 3 components(e,S_(1),S_(2)).We use the technique of hiding the signer’s public key Y,which is the coefficientλgenerated by the group nanager,in the process of forming the group signature and representative collective signature to enhance the privacy of all members of the signing collective. 展开更多
关键词 Computing roots finding roots modulo collective signature signing collective signing group
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Simulation of detection and scattering of sound waves by the lateral line of a fish
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作者 V M Adamyan I Y Popov +1 位作者 I V Blinova V V Zavalniuk 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期398-404,共7页
A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is proposed.Within the framework of this model it is shown that the ratio of pressure... A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is proposed.Within the framework of this model it is shown that the ratio of pressures on lateral lines on different fish flanks,as well as the cross section of sound scattering on both the lines,strongly depends on angles of incidence of incoming sound waves.The strong angular dependence of the pressure ratio seems to be sufficient for the fish to determine the directions from which the sound is coming. 展开更多
关键词 acoustic equation point self-adjoint perturbations of Laplace operator SCATTERING lateral line
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Vitamin D_(3) attenuates anxiety-like behavior in long-term ovariectomized rats with unpredictable mild stress
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作者 DENIS BARANENKO JULIA FEDOTOVA ANNEMIEKE JOHANNA MARIA VAN DEN TOL 《BIOCELL》 SCIE 2019年第4期299-311,共13页
The impact of various vitamin D3(VD3)doses(1.0,2.5,or 5 mg/kg,s.c.)in mitigating the negative consequences of chronic unpredictable mild stress(CUMS)was investigated.Adult female rats with long-term estrogen deficienc... The impact of various vitamin D3(VD3)doses(1.0,2.5,or 5 mg/kg,s.c.)in mitigating the negative consequences of chronic unpredictable mild stress(CUMS)was investigated.Adult female rats with long-term estrogen deficiency were assessed using the sucrose preference test(SPT),the elevated plus-maze(EPM),the light/dark test(LDT),and the open-field test(OFT)to measure anhedonia-like and anxiety-like behavior.The corticosterone(CS)and adrenocorticotrophic hormone(ACTH)concentrations in blood serum and the brain-derived neurotrophic factor(BDNF)expression in the hippocampus of long-term ovariectomized(OVX)rats were measured by ELISA kits and/or western blotting.Treatment with VD3(5.0 mg/kg),similarly to fluoxetine(10.0 mg/kg),significantly reduced the anhedonia profile in the SPT and anxiety-like behavior in the EPM and LDT,and CS and ACTH levels in blood serum.It also elevated BDNF levels in the hippocampus of long-term OVX/CUMS compared to OVX/CUMS/solvent rats.Thus,these findings suggest that VD3(5.0 mg/kg)administration might attenuate the anxiety-like profile in long-term OVX adult rats subjected to the CUMS.This might occur via activation of the BDNF signaling pathway in the hippocampus and via restoration of CS and ACTH levels in blood serum. 展开更多
关键词 ANXIETY BDNF Chronic unpredictable mild stress Long-term ovariectomy Vitamin D3
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Fuzzy Aggregator Based Energy Aware RPL Routing for IoT Enabled Forest Environment
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作者 S.Srividhya Suresh Sankaranarayanan +1 位作者 Sergei A.Kozlov Joel J.P.C.Rodrigues 《Computers, Materials & Continua》 SCIE EI 2022年第8期4039-4055,共17页
Forested areas are extremely vulnerable to disasters leading to environmental destruction.Forest Fire is one among them which requires immediate attention.There are lot of works done by authors where Wireless Sensors ... Forested areas are extremely vulnerable to disasters leading to environmental destruction.Forest Fire is one among them which requires immediate attention.There are lot of works done by authors where Wireless Sensors and IoT have been used for forest fire monitoring.So,towards monitoring the forest fire and managing the energy efficiently in IoT,Energy Efficient Routing Protocol for Low power lossy networks(E-RPL)was developed.There were challenges about the scalability of the network resulting in a large end-to-end delay and less packet delivery which led to the development of Aggregator-based Energy Efficient RPL with Data Compression(CAAERPL).Though CAA-ERPL proved effective in terms of reduced packet delivery,less energy consumption,and increased packet delivery ratio for varying number of nodes,there is still challenge in the selection of aggregator which is based purely on probability percentage of nodes.There has been research work where fuzzy logic been employed for Mobile Ad-hoc Routing,RPL routing and cluster head selection in Wireless Sensor.There has been no work where fuzzy logic is employed for aggregator selection in Energy Efficient RPL.So accordingly,we here have proposed Fuzzy Based Aggregator selection in Energy-efficient RPL for region thereby forming DODAG for communicating to Fog/Edge.We here have developed fuzzy inference rules for selecting the aggregator based on strength which takes residual power,Node degree,and Expected Transmission Count(ETX)as input metrics.The Fuzzy Aggregator Energy Efficient RPL(FA-ERPL)based on fuzzy inference rules were analysed against E-RPL in terms of scalability(First and Half Node die),Energy Consumption,and aggregator node energy deviation.From the analysis,it was found that FA-ERPL performed better than E-RPL.These were simulated using MATLAB and results. 展开更多
关键词 Fuzzy logic aggregator IOT RPL ROUTING wireless sensor network
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In vivo degradability and biocompatibility of a rheo-formed Mg–Zn–Sr alloy for ureteral implantation
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作者 Di Tie Renguo Guan +6 位作者 Huinan Liu Minfang Chen Sviatlana A.Ulasevich Ekaterina V.Skorb Patricia Holt-Torres Xiaopeng Lu Norbert Hort 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第6期1631-1639,共9页
The introduction of biodegradable implant materials has significantly improved the postoperative subjective feelings of patients within the past few decades,among which magnesium alloy is widely considered a favorable... The introduction of biodegradable implant materials has significantly improved the postoperative subjective feelings of patients within the past few decades,among which magnesium alloy is widely considered a favorable choice as its appropriate biodegradability and evident antibacterial activity.Here,we reveal a semisolid rheo-formed Mg–Zn–Sr alloy ureteral implant that displayed suitable degradability and biocompatibility in a pig model.Refined non-dendritic microstructure was observed in the rheo-formed alloy,which led to ca.47%increase in ultimate tensile strength(from 195.0 MPa to 288.1 MPa)and more homogeneous degradation process compared with the untreated alloy.No post-interventional inflammation or pathological changes of the test animals were observed during the implantation period,and the corrosion rate(0.22±0.04 mm·y^(-1))perfectly fitted the clinical ureteral stent indwelling time.The urine bacteria numbers decreased from 88±13 CFU·mL^(-1)at 7 weeks post operation to 59±8 CFU·mL^(-1)at 14 weeks post operation,which confirmed the evident antibacterial activity of the alloy.Our study demonstrates that the Mg–Zn–Sr alloy is clinically safe for urinary system,enabling its efficacious use as ureteral implant materials. 展开更多
关键词 In vivo Biodegradability BIOCOMPATIBILITY Mg–Zn–Sr alloy Ureteral implant
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Churn Prediction Task in MOOC
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作者 Lisitsyna Liubov Oreshin SA 《Journal of Computer Science Research》 2019年第1期29-35,共7页
Churn prediction is a common task for machine learning applications in business.In this paper,this task is adapted for solving problem of low efficiency of massive open online courses(only 5%of all the students finish... Churn prediction is a common task for machine learning applications in business.In this paper,this task is adapted for solving problem of low efficiency of massive open online courses(only 5%of all the students finish their course).The approach is presented on course“Methods and algorithms of the graph theory”held on national platform of online education in Russia.This paper includes all the steps to build an intelligent system to predict students who are active during the course,but not likely to finish it.The first part consists of constructing the right sample for prediction,EDA and choosing the most appropriate week of the course to make predictions on.The second part is about choosing the right metric and building models.Also,approach with using ensembles like stacking is proposed to increase the accuracy of predictions.As a result,a general approach to build a churn prediction model for online course is reviewed.This approach can be used for making the process of online education adaptive and intelligent for a separate student. 展开更多
关键词 Machine learning Data science Exploratory data analysis Logistic regression Gradient boosting on trees STACKING CLASSIFICATION RANKING
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Simplified Step-by-Step Nonlinear Static Program Investigating Equilibrium Conditions of Electrons in Atom and Ionization Energies: Case Study on Argon
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作者 Panagis G. Papadopoulos Christopher G. Koutitas +1 位作者 Yannis N. Dimitropoulos Elias C. Aifantis 《Open Journal of Physical Chemistry》 2018年第2期33-56,共24页
For investigation of equilibrium conditions of electrons in an atom, and Ionization Energies of Elements, a simplified deterministic static model is proposed. The electrons are initially uniformly and sparsely arrange... For investigation of equilibrium conditions of electrons in an atom, and Ionization Energies of Elements, a simplified deterministic static model is proposed. The electrons are initially uniformly and sparsely arranged on the outer surface of nucleus. Then, by taking into account the nucleus-electron interaction (attractive and repulsive) and the mutual electron-electron repulsions, and by a simple step-by-step nonlinear static analysis program, all the electrons are found to equilibrate on the outer surface of the same sphere, which is concentric and larger than nucleus. In a second stage, starting from an equilibrium sphere of electrons, one of the electrons is subjected to gradual forced removal, radially and outwards with respect to nucleus. Within each removal step, the produced work increment is determined and the increments are summed. When no more significant attraction is exerted by nucleus to removed electron, the total work gives the Ionization Energy. After removing of single electron, the remaining electrons fall on a lower shell, that is, they equilibrate on the outer surface of a smaller concentric sphere. For nucleus-electron interaction, an L-J (Lennard-Jones) type curve, attractive and repulsive, is adopted. When the parameter of this curve is n > 1.0, the Ionization Energy exhibits an upper bound. As parameter n increases from 1.0 up to 2.0, the attractive potential of L-J curve is gradually weakened. The proposed model is applied on Argon. It is observed that, as the number of electrons increases, the radius of equilibrium sphere increases, too, whereas the attractive nucleus-electron potential is reduced;thus the Ionization Energy is reduced, too. Particularly, as the number of electrons and the radius of equilibrium sphere exceed some critical values, the above two last quantities exhibit abrupt falls. A regular polyhedron is revealed, which can accommodate Elements up to atomic number Z = 146, that is 28 more than Z = 118 of existing last Element, as guide for initial locations of electrons in the above first program. 展开更多
关键词 Ionization Energy Electrostatic LAWS LENNARD-JONES Curve Incremental Nonlinear Static Analysis Atomic Radius Rhombic Dodecahedron Regular POLYHEDRON
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Molecular Dynamics Simulation of Interaction of Short Lysine Brush and Oppositely Charged Semax Peptides
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作者 Elena Popova Boris Okrugin Igor Neelov 《Natural Science》 2016年第12期499-510,共12页
The possibility of complex formation by short lysine brush and therapeutic Semax peptides was investigated using molecular dynamics method. Lysine dendrimers and polymer brushes are used for drug and other (e.g., DNA,... The possibility of complex formation by short lysine brush and therapeutic Semax peptides was investigated using molecular dynamics method. Lysine dendrimers and polymer brushes are used for drug and other (e.g., DNA, peptides, and polysaccharides) molecules delivery to different target cells. It is known that they could penetrate blood brain barrier. Since short lysine brush is nontoxic, a system containing of such brush and 8 oppositely charged Semax peptides was studied. It was obtained that stable complexes consisting of brush and peptides formed and structures of these complexes were investigated. Such complex can be used in future for delivery of Semax peptides to brain since these peptides have significant antioxidant, antihypoxic and neuroprotective effects. 展开更多
关键词 Lysine Brush Semax Peptides Computer Simulation Method of Molecular Dynamics
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Intestinal microbiome changes in an infant with right atrial isomerism and recurrent necrotizing enterocolitis:A case report and review of literature
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作者 Aleksandra Kaplina Ekaterina Zaikova +13 位作者 Artem Ivanov Yulia Volkova Tatiana Alkhova Vladimir Nikiforov Alexander Latypov Marina Khavkina Tatiana Fedoseeva Tatiana Pervunina Yulia Skorobogatova Svetlana Volkova Vladimir Ulyantsev Olga Kalinina Stanislav Sitkin Natalia Petrova 《World Journal of Clinical Cases》 SCIE 2022年第29期10583-10599,共17页
BACKGROUND Necrotizing enterocolitis(NEC)is a multifactorial disease that predominantly affects premature neonates.Intestinal dysbiosis plays a critical role in NEC pathogenesis in premature neonates.The main risk fac... BACKGROUND Necrotizing enterocolitis(NEC)is a multifactorial disease that predominantly affects premature neonates.Intestinal dysbiosis plays a critical role in NEC pathogenesis in premature neonates.The main risk factor for NEC in term infants is mesenteric hypoperfusion associated with ductaldependent congenital heart disease(CHD)that eventually leads to intestinal ischemia.The incidence of NEC in neonates with critical CHD is 6.8%-13%.However,the role of the intestinal microbiome in NEC pathogenesis in infants with ductal-dependent CHD remains unclear.CASE SUMMARY A male term neonate with right atrial isomerism underwent modified Blalock-Taussig shunt placement on the 14^(th)day of life and had persistent mesenteric hypoperfusion after surgery.The patient had episodes of NEC stageⅡA on the 1^(st)and 28^(th)days after cardiac surgery.Fecal microbial composition was analyzed before and after cardiac surgery by sequencing region V4 of the 16S rRNA gene.Before surgery,species belonging to genera Veillonella and Clostridia and class Gammaproteobacteria were detected,Bifidobacteriaceae showed a low abundance.The first NEC episode was associated with postoperative hemodynamic instability,intestinal ischemiareperfusion injury during cardiopulmonary bypass,and a high abundance of Clostridium paraputrificum(Clostridium sensu stricto I)(56.1%).Antibacterial therapy after the first NEC episode resulted in increased abundance of Gammaproteobacteria,decreased abundance of Firmicutes,and low alpha diversity.These changes in the microbial composition promoted the growth of Clostridium sensu strictoⅠ(72.0%)before the second NEC episode.CONCLUSION A high abundance of Clostridium sensu strictoⅠand mesenteric hypoperfusion may have contributed to NEC in the present case. 展开更多
关键词 Necrotizing enterocolitis Congenital heart disease Ivemark syndrome HETEROTAXY Right atrial isomerism Intestinal microbiome Case report
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