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Crop adaptation to climate change:An evolutionary perspective

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Molecular Plant 2023年第10期16卷 1518-1546页

作者： Lexuan Gao Michael b.Kantar Dylan Moxley Daniel Ortiz-barrientos Loren H.Rieseberg CAs Center for Excellence in Molecular Plant sciences Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China Department of Tropical Plant&soil sciences University of Hawaii at ManoaHonoluluHIUSA Department of botany and biodiversity Research Centre University of British ColumbiaVancouverBCCanada school of biological sciences and Australian Research Council Centre of Excellence for Plant success in Nature and Agriculture The University of QueenslandBrisbaneQLDAustralia

The disciplines of evolutionary biology and plant and animal breeding have been intertwined throughout their development,with responses to artificial selection yielding insights into the action of natural selection and evolutionary biology providing statistical and conceptual guidance for modern *** we offer an evolutionary perspective on a grand challenge of the 21st century:feeding humanity in the face of climate *** first highlight promising strategies currently under way to adapt crops to current and future climate *** include methods to match crop varieties with current and predicted environments and to optimize breeding goals,management practices,and crop microbiomes to enhance yield and sustainable *** also describe the promise of crop wild relatives and recent technological innovations such as speed breeding,genomic selection,and genome editing for improving environmental resilience of existing crop varieties or for developing new ***,we discuss how methods and theory from evolutionary biology can enhance these existing strategies and suggest novel *** focus initially on methods for reconstructing the evolutionary history of crops and their pests and symbionts,because such historical information provides an overall framework for crop-improvement *** then describe how evolutionary approaches can be used to detect and mitigate the accumulation of deleterious mutations in crop genomes,identify alleles and mutations that underlie adaptation(and maladaptation)to agricultural environments,mitigate evolutionary trade-offs,and improve critical *** feedback between the evolution and crop biology communities will ensure optimal design of strategies for adapting crops to climate change.

关键词： abiotic stress resistance climate change crop adaptation Darwinian agriculture evolutionary biology plant breeding

Design and guidance of a multi-active debris removal mission

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Astrodynamics 2023年第4期7卷 383-399页

作者： Minduli C.Wijayatunga(b) Roberto Armellin Harry Holt Laura Pirovano Aleksander A.Lidtke Te Pūnaha Atea–space Institute The University of AucklandAuckland 1010New Zealand Astroscale Japan Inc. 1-16-4-16 KinshiSumida-kuTokyoJapan

space debris have become exceedingly dangerous over the years as the number of objects in orbit continues to *** debris removal(ADR)missions have gained significant interest as effective means of mitigating the risk of collision between objects in *** study focuses on developing a multi-ADR mission that utilizes controlled reentry and *** mission comprises two spacecraft:a servicer that brings debris to a low altitude and a shepherd that rendezvous with the debris to later perform a controlled reentry.A preliminary mission design tool(PMDT)was developed to obtain time and fuel optimal trajectories for the proposed mission while considering the effect of J2,drag,eclipses,and duty *** PMDT can perform such trajectory optimizations for multi-debris missions with computational time under a *** guidance schemes are also studied,taking the PMDT solution as a reference to validate the design methodology and provide guidance solutions to this complex mission profile.

关键词： active debris removal(ADR) trajectory design optimization autonomous guidance low-thrust electric propulsion △u-law guidance Q-law guidance

Pathogenesis of Thrombocytopenia in Chronic HCV Infection:A Review

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Journal of Clinical and Translational Hepatology 2020年第2期8卷 184-191页

作者： sarah Rawi George y Wu Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

A large proportion of patients with chronic hepatitis C have associated thrombocytopenia (TCP). Due to bleeding risks, TCP, when severe, can limit diagnostic and therapeutic procedures, treatments, and increases risk of complications, especially excessive bleeding. It is important to understand the mechanisms that cause TCP in order to manage it. In general, TCP can be due to increased destruction or decreased production. Proposed mechanisms of increased destruction include autoantibodies to platelets and hyper-splenism with sequestration. Proposed mechanisms of de-creased production include virus-induced bone marrow suppression and decreased TPO production. Autoantibodies directed against platelet surface antigens have demonstrated an inverse correlation with platelet counts. Hypersplenism with sequestration involves the interaction of portal hyper-tension, splenomegaly, and platelet destruction. Decreased production mechanisms involve appropriate and inappropri-ate levels of TPO secretion. There is limited evidence to support viral-induced bone marrow suppression. In contrast, there is strong evidence to support low levels of TPO in liver failure as a major cause of TCP. TPO-agonists, specifically eltrombopag, have been shown in hepatitis C patients to increase platelet counts without reducing portal hypertension or splenomegaly. We conclude that TCP in hepatitis C virus-induced liver disease is often multifactorial, but an under-standing of the mechanisms can lead to judicious use of new drugs for treatment.

关键词： Thrombocytopenia Chronic hepatitis Autoantibodies Hypersplenism Thrombopoietin

Enhanced Metaheuristics with Machine Learning Enabled Cyberattack Detection Model

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Intelligent Automation & soft Computing 2023年第9期37卷 2849-2863页

作者： Ahmed s.Almasoud Department of Information systems College of Computer and Information SciencesPrince Sultan UniversityRiyadh12435Saudi Arabia

The Internet of Things(IoT)is considered the next-gen connection network and is ubiquitous since it is based on the *** Detection system(IDs)determines the intrusion performance of terminal equipment and IoT communication procedures from IoT environments after taking equivalent defence measures based on the identified *** this back-ground,the current study develops an Enhanced Metaheuristics with Machine Learning enabled Cyberattack Detection and Classification(EMML-CADC)model in an IoT *** aim of the presented EMML-CADC model is to detect cyberattacks in IoT environments with enhanced *** attain this,the EMML-CADC model primarily employs a data preprocessing stage to normalize the data into a uniform *** addition,Enhanced Cat swarm Optimization based Feature selection(ECsO-Fs)approach is followed to choose the optimal feature ***,Mayfly Optimization(MFO)with Twin support Vector Machine(TsVM),called the MFO-TsVM model,is utilized for the detection and classification of ***,the MFO model has been exploited to fine-tune the TsVM variables for enhanced *** performance of the proposed EMML-CADC model was validated using a benchmark dataset,and the results were inspected under several *** comparative study concluded that the EMML-CADC model is superior to other models under different measures.

关键词： Metaheuristics cyberattack detection machine learning cat swarm optimization security

Effect of heat treatment on the microstructures and mechanical properties of the sand-cast Mg-2.7Nd-0.6Zn-0.5Zr alloy

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Journal of Magnesium and Alloys 2014年第1期2卷 20-26页

作者： D.Wu y.Q.Ma R.s.Chen W.Ke The Group of Magnesium and Their Applications Institute of Metal ResearchChinese Academy of Sciences62 Wencui RoadShenyang 110016China

The tensile testing bars of the Mg-2.7Nd-0.6Zn-0.5Zr(wt.%)alloy were prepared by sand *** effect of solution temperature and aging time on the microstructures and mechanical properties were *** as-cast alloy was composed ofαmagnesium matrix and Mg12Nd eutectic *** solution treatment at 500℃ for 18 h,the volume fraction of eutectic compounds decreased from∼7.8%to∼2.3%,and some small Zr-containing particles were observed to precipitate at grain *** the solution temperature increased to 525℃ for 14 h,most of the eutectic compounds dissolved into the ***-aged at 200℃ for 12 h,fineβ″particles was the dominant strengthening *** yield strength,ultimate tensile strength and elongation in the peak-aged condition were 191 MPa,258 MPa and 4.2%,***,the Mg-2.7Nd-0.6Zn-0.5Zr alloys under different heat treatment conditions exhibited different tensile fracture modes.

关键词： Magnesium alloy sand-cast Heat treatment Microstructure Mechanical properties

EFFECT OF HEAT TREATMENT ON RECOVERy sTREss OF Fe-18Mn-5si-8Cr-4Ni ALLOy

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Acta Metallurgica sinica(English Letters) 1999年第5期12卷 743-746页

作者： Li, N. Wen, y.H. Xu, y.G. Tu, M.J. Li, P.Q. Liu, y.L. Ma, y.L. sichuan Univ Chengdu China

The effect of quenching temperature on the recovery stress of Fe 18Mn 5si 8Cr 4Ni shape memory alloy has been studied. The results show that both the maximum recovery stress σ h in heating and the recovery stress σ c at room temperature after heating increased as increasing quenching temperature increased, both σ h and σ c reached maximum at 650℃, and then decreased rapidly with the further increase in quenching temperature,but the descent degree of σ c was far bigger than that of σ h; When the quenching temperature is higher than 850℃, the further increase in quenching temperature had little effect on them; At random quenching temperature, σ c was far bigger than σ h.

关键词： shape memory alloy quenching recovery stress

Mercury levels in human population from a mining district in Western Colombia

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Journal of Environmental sciences 2018年第6期30卷 83-90页

作者： Harry Gutiérrez-Mosquera s.b.sujitha M.P.Jonathan s.K.sarkar Fairy Medina-Mosquera Helcias Ayala-Mosquera Gladis Morales-Mira Laura Arreola-Mendoza Facultad de Ingenieria Universidad Tecnologica del Choco Carrera 22 No.18B-10 Quibdo Colombia Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo (CIIEMAD) Instituto Politecnico Nacional (IPN) Calle 30 de junio de 1520 Barrio la Laguna Ticomdn Del. Gustavo A. Madero C.P.07340 Ciudad de Mexico Mexico Department of Marine science University of Calcutta 35 Ballygunge Circular Road Calcutta 700 019 India Instituto de Investigaciones Ambientales del Pacifico (IIAP) Carrera 6 No. 37-39 quibdo Colombia Facultad de Ingenieria Uniuersidad de Medellin Carrera 87 No. 30-65 Medellin Colombia

A biomonitoring study was carried out to examine the adverse impacts of total mercury in the blood（Hgb）, urine（Hg U） and human scalp hair（HgH） on the residents of a mining district in Colombia. Representative biological samples（scalp hair, urine and blood） were collected from volunteered participants（n = 63） to estimate the exposure levels of THg using a Direct mercury analyzer. The geometric mean of THg concentrations in the hair,urine and blood of males were 15.98 μg/g, 23.89 μg/L and 11.29 μg/L respectively, whereas the females presented values of 8.55 μg/g, 5.37 μg/L and 8.80 μg/L. Chronic urinary Hg（HgU）levels observed in male workers（32.53 μg/L） are attributed to their long termed exposures to inorganic and metallic mercury from gold panning activities. On an average, the levels of THg are increasing from blood（10.05 μg/L） to hair（12.27 μg/g） to urine（14.63 μg/L）.significant positive correlation was found between hair and blood urinary levels in both male and female individuals. Thus the present biomonitoring investigation to evaluate the Hg levels and associated health issues would positively form a framework for further developmental plans and policies in building an ecofriendly ecosystem.

关键词： Humans Mercury Gold panning biomarkers Toxicity Colombia

Fruit Juice Production in Abomey-Calavi and Cotonou Municipalities (benin): socio-Professional Profile of Actors and Adoption Level of Hygienic Practices of Enterprises

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Food and Nutrition sciences 2022年第7期13卷 649-668页

作者： Agossou P. Noumavo Messan A. b. Ohin d’Avila y. Dognon stéphane K. Houessou Edmond sacla Aide Farid baba-Moussa Laboratoire de Microbiologie et des Technologies Alimentaires Faculté des Sciences et Techniques Université d’Abomey-Calavi Abomey-Calavi Bénin Laboratoire de biologie et de Typage Moléculaire en Microbiologie Faculté des Sciences et Techniques Université d’Abomey-Calavi Abomey-Calavi Bénin Laboratoire de biomathématiques et Estimation Forestière Faculté des Sciences Agronomiques Université d’Abomey-Calavi Abomey-Calavi Bénin

Fruit juice production sector is developing in benin’s major cities and appears to have both organisational and technical shortcomings. This study aimed to 1) establish the socio-professional profile of actors in the fruit juice production sector in Abomey-Calavi and Cotonou municipalities and 2) evaluate the adoption level of hygienic practices of enterprises. The methodological approach adopted in this study combined a semi-structured survey with direct observations in fifty enterprises. The statistical analysis was carried out using the R.4.0.0 software. The study revealed that fruit juice enterprises in both municipalities are mainly artisanal (90%) and located in residential areas (94%). They are therefore exposed to contamination risks from domestic and road activities. More than half of these enterprises were created less than five years ago. Three administrative types of enterprises were noted: non-structured (32%), semi-structured (34%) and structured (34%). Almost half of the enterprises belong to at least one professional association. Only a few enterprises have marketing authorization. Women predominate in the positions of director and production assistant. The majority of production managers are men. Most directors and production managers have a university education, but not necessarily in the field of food sciences. The adoption level of hygienic practices is significantly influenced by the level of enterprises structuration and size. The level of hygiene in these enterprises is also very weakly influenced by the female gender. structured and semi-industrial enterprises have a higher adoption level of hygienic practices. Those with acceptable or good hygiene level enterprises contain slightly more women.

关键词： Fruit Juice Food Hygiene socio-Demographic Profile Gender benin

spin-correlation function of the fully frustrated Ising model and ±J Ising spin glass on a square lattice

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Chinese Physics b 2013年第6期22卷 549-552页

作者： M y Ali J Poulter Department of Mathematics Faculty of ScienceMahidol University

In this work we study the correlation function of the ground state of a two-dimensional fully frustrated Ising model as well as spin glass. The Pfaffian method is used to calculate free energy and entropy as well as the correlation function. We estimate the exponent of spin correlation function for the fully frustrated model and spin glass. In this paper an overview of the latest results on the spin correlation function is presented.

关键词： spin glass correlation function exponent square lattice