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Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期 34-42页

作者： Leonarde do Nascimento Rodrigues Wesley Fiorio lnoch Marcos L.F.Gomes Odilon D.D.Couto jr. Bráulio S.Archanjo Sukarno Olavo Ferreira Physics Department Federal University of Vi?osa Instituto de Física Gleb Wataghin Universidade Estadual de Campinas National Institute of Metrology Quality and Technology (Inmetro) Materials Metrology Division (DIMAT)

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

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Estimating the Drought-Induced Yield Loss for Winter Wheat in a Semi-Arid Region of the Southern United States Using a Drought Index

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Agricultural Sciences 2024年第8期15卷 812-829页

作者： Prem Woli Qingwu Xue Gerald R. Smith Charles R. Long Francis M. Rouquette jr. Texas A&M AgriLife Research Center Overton Texas USA Texas A&M AgriLife Research Center Amarillo Texas USA

The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This region is prone to drought and is projected to experience a drier climate. Droughts that coincide with the critical phenological phases of a crop can be remarkably costly. Although drought cannot be prevented, its losses can be minimized through mitigation measures if it is predicted in advance. Predicting yield loss from an imminent drought is an important need of stakeholders. One way to fulfill this need is using an agricultural drought index, such as the Agricultural Reference Index for Drought (ARID). Being plant physiology-based, ARID can represent drought-yield relationships accurately. This study developed an ARID-based yield model for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to water stress. The reasonable values of the drought sensitivity coefficients of the yield model indicated that it could reflect the phenomenon of water stress decreasing the winter wheat yields in this region reasonably. The values of the various metrics used to evaluate the model, including Willmott Index (0.86), Nash-Sutcliffe Index (0.61), and percentage error (26), indicated that the yield model performed fairly well at predicting the drought-induced yield loss for winter wheat. The yield model may be useful for predicting the drought-induced yield loss for winter wheat in the study region and scheduling irrigation allocation based on phenological phase-specific drought sensitivity.

关键词： ARID Drought Drought index Growth-stage Model Phenological-Phase Prediction Semi-Arid Wheat Yield

Machine Learning Empowered Security and Privacy Architecture for IoT Networks with the Integration of Blockchain

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Intelligent Automation & Soft Computing 2024年第2期39卷 353-379页

作者： Sohaib Latif M.Saad Bin Ilyas Azhar Imran Hamad Ali Abosaq Abdulaziz Alzubaidi Vincent Karovic jr. Department of Computer Science The University of ChenabGujrat50700Pakistan Department of Creative Technologies Air UniversityIslamabad42000Pakistan Computer Science Department College of Computer Science and Information SystemsNajran UniversityNajran66244Saudi Arabia Department of Computer Science Umm Alqura UniversityAlQunfudah28821Saudi Arabia Department of Information Systems Faculty of ManagementComenius University in BratislavaBratislava82005Slovakia

The Internet of Things(IoT)is growing rapidly and impacting almost every aspect of our lives,fromwearables and healthcare to security,traffic management,and fleet management *** has generated massive volumes of data and security,and data privacy risks are increasing with the advancement of technology and network *** access control solutions are inadequate for establishing access control in IoT systems to provide data protection owing to their vulnerability to single-point OF ***,conventional privacy preservation methods have high latency costs and overhead for resource-constrained *** machine learning approaches were also unable to detect denial-of-service(DoS)*** study introduced a novel decentralized and secure framework for blockchain *** avoid single-point OF failure,an accredited access control scheme is incorporated,combining blockchain with local peers to record each transaction and verify the signature to ***-based attribute-based cryptography is implemented to protect data storage privacy by generating threshold parameters,managing keys,and revoking users on the *** innovative contract-based DOS attack mitigation method is also incorporated to effectively validate devices with intelligent contracts as trusted or untrusted,preventing the server from becoming *** proposed framework effectively controls access,safeguards data privacy,and reduces the risk of *** results depict that the suggested framework outperforms the results in terms of accuracy,precision,sensitivity,recall,and F-measure at 96.9%,98.43%,98.8%,98.43%,and 98.4%,respectively.

关键词： Machine learning internet of things blockchain data privacy security Industry 4.0

Molecular Docking Studies on Streptomycin Antileishmanial Activity

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Open Journal of Physical Chemistry 2024年第2期14卷 36-48页

作者： Todd A. Young Matthew George jr. Ayele Gugssa William M. Southerland Yayin Fang Clarence M. Lee Department of Biology Howard University Washington DC United States Department of Biochemistry and Molecular Biology Howard University Washington DC United States

Resistance to pentavalent antimonial drugs and the lack of vaccines make it urgent to find novel therapeutic options to treat Leishmaniasis, a tropical disease caused by the Leishmania protozoan parasite. The study reported here is to investigate if Streptomycin, an aminoglycoside, and Amphotericin B, the second-line treatment drug, exhibit antileishmanial activity through a similar mechanism. By using MOE (Molecular Operating Environment), we performed molecular docking studies on these drugs binding to a range of targets including ribosome targets in Leishmania and H. sapiens. Our study shows that the two drugs do not bind to the same pockets in Leishmania targets but to the same pockets in the human ribosome, with some differences in interactions. Moreover, our 2D maps indicated that Amphotericin B binds to the A-site in the human cytoplasmic ribosome, whereas streptomycin does not.

关键词： Leishmaniasis Streptomycin Amphotericin B Molecular Docking Aminoglycosides Antileishmanial

Enhancement of mechanical properties of GTAW joints for ZC63 magnesium alloy by post-weld heat treatment

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Journal of Materials Science & Technology 2024年第2期169卷 251-263页

作者： Weiyang Zhou Qichi Le Ye Shi Qiyu Liao Tong Wang Qi Zou Clodualdo Aranas jr Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Department of Mechanical Engineering University of New BrunswickFrederictonE3B 5A3New BrunswickCanada

To further improve the microstructure and mechanical properties of gas tungsten arc welded(GTAW)welded joints for ZC63 magnesium alloy,post-weld heat treatment is carried *** is found that the majority of the MgZnCu phase in the fusion zone(FZ)is dissolved in theα-Mg matrix under suitable heat treatment *** remainder is diffusely distributed as rods or granules at the grain *** excessive heat treatment temperature(460℃)leads to abnormal grain growth(AGG)in the *** substructure gradient between the abnormally grown grains and the surrounding small grains pro-vides the driving force for ***,the dissolution of the MgZnCu phase weakens the hindering effect of the second phase on grain boundary migration,setting the stage for *** addition,the detri-mental impact of the continuous MgZnCu phase on the mechanical properties of the welded joint is also lessened by its *** ultimate tensile strength(UTS),yield strength(YS)and elongation(EL)of the welded joints are 255 MPa,119 MPa and 27.0%,respectively,under the post-weld heat treatment process of 440℃×12 *** welding coefficient of the welded joint reaches 97.0%,satisfying the service criteria set forth by the mechanical properties of the welded joints.

关键词： GTAW FZ Heat treatment AGG Mechanical properties

Fish culture in biofloc technology(BFT):Insights on stocking density carbon sources,C/N ratio,fish nutrition and health

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Aquaculture and Fisheries 2024年第4期9卷 522-533页

作者： Luciana Kelly Oliveira Wilson Wasielesky jr.Marcelo Borges Tesser Laboratorio de Nutriçao de Organismos Aqu´aticos Instituto de OceanografiaUniversidade Federal do Rio Grande-FURG-Rua do Hotel02-CassinoRio Grande96201-900Brazil Laborat´orio de Carcinocultura Instituto de OceanografiaUniversidade Federal do Rio Grande-FURG-Rua do Hotel02-CassinoRio Grande96201-900Brazil

The growth of aquaculture demands intense consumption of formulated foods,scarce natural resources such as water and *** increase in aquaculture production needs to be sustainable in several aspects of the activity,including the use of more sustainable farming systems that provide reduced water demand,less space dependence for increased production,and availability of complementary natural *** this perspective,the biofloc system(BFT),presents itself as a more friendly cultivation technology as a way to mitigate some impacts of aquaculture *** research has been carried out,addressing different aspects important to the production of fish in *** this review,we address how stocking density,carbon sources and carbon nitrogen ration(C/N)affect animal performance and the nutritional value of bioflocs;the use of microbial aggregates as“in situ”and“ex situ”food and the benefits in feed conversion,and their influence on the immune system and disease resistance.

关键词： Biofloc technology Aquaculture system Natural food Nutritional value Fish health

Development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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Journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher Michael J.LaMonte Andrea Z.LaCroix Eleanor M.Simonsick Steven P.Hooker Humberto Parada jr. John Bellettiere Arun Kumar Herbert Wertheim School of Public Health and Human Longevity Science University of California San DiegoLa JollaCA 92093USA Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego Moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and Halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(ML),and none specifically for older *** direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several ML VO_(2max)prediction ***:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVM)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an inverse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:Measured VO_(2max)is a strong predictor of *** ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithms Epidemiology Mortality

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机器人加速入侵肉类加工业

商业周刊（中文版） 2024年第7期 10-12页

作者： Gerson Freitas jr. Isis Almeida 永年(译) 不详

机器学习和人工智能意味着精通高精度工作的不再只有人类了。在美国大平原上,遥控机器人在为农业巨头嘉吉公司(Cargill)放牛。在美国各地的肉类加工厂里,机器人在准备货物、堆放托盘。在家禽业巨头韦恩-桑德森农场(Wayne-Sanderson Farm... 详细信息

机器学习和人工智能意味着精通高精度工作的不再只有人类了。在美国大平原上,遥控机器人在为农业巨头嘉吉公司(Cargill)放牛。在美国各地的肉类加工厂里,机器人在准备货物、堆放托盘。在家禽业巨头韦恩-桑德森农场(Wayne-Sanderson Farms),一套机器设备在雏鸡出生时给它们接种疫苗,几周后则有另套机器将它们开肠破肚,取出内脏。乍一看,在这个世界上劳动密集程度最高的行业之一,美国肉类加工商似乎已经成功地从人工转向了机器。

关键词：肉类加工业肉类加工厂遥控机器人机器设备机器学习劳动密集家禽业人工智能

Asymptomatic postpubertal male with equally sized normal testicles with palpable left varicocele

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Asian Journal of Andrology 2016年第2期18卷 310-310页

作者： A Scott Polackwich edmund sabanegh jr Male Infertility and Microsurgery Department of Urology Glickman Urological and Kidney Institute Cleveland Clinic Foundation 9500 Euclid Avenue QIOCleveland OH 44195 USA

Varicoceles are a common finding in the general public. The incidence appears to increase later in life with a contemporary study finding an increase in incidence of 10% per decade of life） While common in the general population, they are even more common among those presenting for a fertility evaluation, as high as 39% in some series and are often initially diagnosed during such examinations） Others present without symptoms or fertility issues and are found incidentally on a physical exam by a general practitioner.

关键词： MEN