Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical ...Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical design of the system, the causes of the distortion are given and a distortion model is established. Then, a quick and accurate self-calibration method is designed. The experiments indicate that the method can calibrate the two image sensors of the system at the same time,the average pixel deviation of the calibrated system is less than 0.5pixels and the maximum deviation is less than 1 pixel.展开更多
The well-known El Nio event, the abnormal increase of Equatorial sea surface temperature of the east Pacific Ocean exerts significant influence on the global-scale atmospheric circulation and climatical anomaly in var...The well-known El Nio event, the abnormal increase of Equatorial sea surface temperature of the east Pacific Ocean exerts significant influence on the global-scale atmospheric circulation and climatical anomaly in various areas. The El Nio events have been reported to result from an earlier-stage warm water accumulation in the west Pacific and the eastward transmission of Kelvin waves caused by the collapse of the SE trades, or rolated to the weakening of the trades led by decrease of SE Pacific high.展开更多
Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postu...Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic neurons.In addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-synuclein.Although it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s disease.In addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative disorders.Among such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s disease.Environmental enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating neurotransmission.In this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic factors.We describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease.展开更多
In recent decades,genetic advances in yield improvement in the major cereal crops,including wheat,has stagnated or proceeded at a slower rate than is required to meet future global food demand,particularly in the face...In recent decades,genetic advances in yield improvement in the major cereal crops,including wheat,has stagnated or proceeded at a slower rate than is required to meet future global food demand,particularly in the face of climate change.To reverse this situation,and in view of the future climate scenario,there is a need to increase the genetic diversity of wheat to increase its productivity,quality,stability,and adaptation to local agro-environments.The abundant genetic resources and literature are a basis for wheat improvement.However,many species,such as wild relatives,landraces,and old cultivars have not been studied beyond their agronomic characteristics,highlighting the lack of understanding of the physiological and metabolic processes(and their integration) associated with higher productivity and resilience in limiting environments.Retrospective studies using wheat ancestors and modern cultivars may identify novel traits that have not previously been considered,or have been underestimated,during domestication and breeding,but that may contribute to future food security.This review describes existing wheat genetic diversity and changes that occurred during domestication and breeding,and considers whether mining natural variation among wheat ancestors offers an opportunity to enhance wheat agronomic performance,spike architecture,canopy-and organ-level photosynthetic capacity,and responses to abiotic stress,as well as to develop new wheat hybrids.展开更多
In the last decades,vanadium alloyed coatings have been introduced as potential candidates for self-lubrication due to their perfect tribological properties.In this work,the influence of V incorporation on the wear pe...In the last decades,vanadium alloyed coatings have been introduced as potential candidates for self-lubrication due to their perfect tribological properties.In this work,the influence of V incorporation on the wear performance and oxidation resistance of TiSiN/CrN film coatings deposited by direct current(DC)reactive magnetron sputtering is investigated.The results show that vanadium incorporation significantly decreases the oxidation resistance of the coatings.In general,two layers are formed during the oxidation process:i)Ti(V)O_(2) on top,followed by a protective layer,which is subdivided into two layers,Cr_(2)O_(3) and Si-O.ii)The diffusion of V controls the oxidation of V-containing coatings.The addition of vanadium improves the wear resistance of coatings,and the wear rate decreases with increasing V content in the coatings;however,the friction coefficient is independent of the chemical composition of the coatings.The wear of the V-containing coatings is driven by polishing wear.展开更多
The electronic product has gravitated towards component miniaturization and integration, employment of lead-free materials, and low-temperature soldering processes. Noble-metal aerogels have drawn increasing attention...The electronic product has gravitated towards component miniaturization and integration, employment of lead-free materials, and low-temperature soldering processes. Noble-metal aerogels have drawn increasing attention for high conduction and low density. However,the noble metal aerogels with outstanding solderability were rarely studied. This work has successfully synthesized an aerogel derived from silver nanowires(AgNWs) using a liquid phase reduction method. It is found that the noble metal aerogels can be made into diverse aerogel preformed soldering sheets. The influence of bonding temperature(150-300 ℃), time(2-20 min), and pressure(5-20 MPa) on the joint strength of the AgNWs aerogel affixed to electroless nickel/silver copper plates were investigated. Additionally, the AgNWs aerogel displays almost the same shear strength for substrates of various sizes. In a word, this study presents a flux-free, high-strength, and adaptable soldering structural material.展开更多
基金supported by the National High Technology Research and Development Program of China (20152AA7031010B)。
文摘Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical design of the system, the causes of the distortion are given and a distortion model is established. Then, a quick and accurate self-calibration method is designed. The experiments indicate that the method can calibrate the two image sensors of the system at the same time,the average pixel deviation of the calibrated system is less than 0.5pixels and the maximum deviation is less than 1 pixel.
文摘The well-known El Nio event, the abnormal increase of Equatorial sea surface temperature of the east Pacific Ocean exerts significant influence on the global-scale atmospheric circulation and climatical anomaly in various areas. The El Nio events have been reported to result from an earlier-stage warm water accumulation in the west Pacific and the eastward transmission of Kelvin waves caused by the collapse of the SE trades, or rolated to the weakening of the trades led by decrease of SE Pacific high.
文摘Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic neurons.In addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-synuclein.Although it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s disease.In addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative disorders.Among such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s disease.Environmental enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating neurotransmission.In this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic factors.We describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease.
基金the support of Funda??o para a Ciência e a Tecnologia (FCT, Portugal), through the GREEN-IT–Bioresources for Sustainability R&D Unit (UIDB/04551/2020, UIDP/04551/2020)the LS4FUTURE Associated Laboratory (LA/P/0087/2020)+1 种基金funded by FCT through the Program ‘Concurso de Estímulo ao Emprego Científico Institucional’ (CEECINST/00102/2018/CP1567/CT0039)the support from ICREA Acadèmia, Generalitat de Catalunya, and the project PID2019-106650RB-C21 from the Ministerio de Ciencia e Innovación, Spain。
文摘In recent decades,genetic advances in yield improvement in the major cereal crops,including wheat,has stagnated or proceeded at a slower rate than is required to meet future global food demand,particularly in the face of climate change.To reverse this situation,and in view of the future climate scenario,there is a need to increase the genetic diversity of wheat to increase its productivity,quality,stability,and adaptation to local agro-environments.The abundant genetic resources and literature are a basis for wheat improvement.However,many species,such as wild relatives,landraces,and old cultivars have not been studied beyond their agronomic characteristics,highlighting the lack of understanding of the physiological and metabolic processes(and their integration) associated with higher productivity and resilience in limiting environments.Retrospective studies using wheat ancestors and modern cultivars may identify novel traits that have not previously been considered,or have been underestimated,during domestication and breeding,but that may contribute to future food security.This review describes existing wheat genetic diversity and changes that occurred during domestication and breeding,and considers whether mining natural variation among wheat ancestors offers an opportunity to enhance wheat agronomic performance,spike architecture,canopy-and organ-level photosynthetic capacity,and responses to abiotic stress,as well as to develop new wheat hybrids.
基金financially supported by the National Natural Science Foundation of China(Nos.51801081 and 52171071)national funds through FCT of Portugal-Fundacao para a Ciencia e a Tecnologia,under a scientific contract of 2021.04115,CEMMPRE-ref.“UIDB/00285/2020”and LA/P/0112/2020 projects+2 种基金FEDER funds through the COMPETE program-Operational Program on Competitiveness Factorsnational funds through FCT-Foundation for Science and Technology,Outstanding University Young Teachers of“Qing Lan Project”of Jiangsu Province of China,Excellent Talents of“Shenlan Project”of Jiangsu University of Science and Technology of ChinaA part of this study was supported by the Directorate-General of Scientific Research and Technological Development(Algeria)。
文摘In the last decades,vanadium alloyed coatings have been introduced as potential candidates for self-lubrication due to their perfect tribological properties.In this work,the influence of V incorporation on the wear performance and oxidation resistance of TiSiN/CrN film coatings deposited by direct current(DC)reactive magnetron sputtering is investigated.The results show that vanadium incorporation significantly decreases the oxidation resistance of the coatings.In general,two layers are formed during the oxidation process:i)Ti(V)O_(2) on top,followed by a protective layer,which is subdivided into two layers,Cr_(2)O_(3) and Si-O.ii)The diffusion of V controls the oxidation of V-containing coatings.The addition of vanadium improves the wear resistance of coatings,and the wear rate decreases with increasing V content in the coatings;however,the friction coefficient is independent of the chemical composition of the coatings.The wear of the V-containing coatings is driven by polishing wear.
基金the National Natural Science Foundation of China(Grant No.52075125,No.52105331)the Shenzhen Science and Technology Innovation Committee(Grant No.JCYJ20210324124203009,No.JSGG20201102154600003,No.GXWD20220818163456002)+1 种基金Special Fund for Science and Technology Innovation Strategy of Guangdong Province(Grant No.pdjh2022b0570)Sustainedly Supported Fundation by National Key Laboratory of Science and Technology on Space Microwave under Grant HTKJ2022KL504011,and NIO University Programme(NIO UP).
文摘The electronic product has gravitated towards component miniaturization and integration, employment of lead-free materials, and low-temperature soldering processes. Noble-metal aerogels have drawn increasing attention for high conduction and low density. However,the noble metal aerogels with outstanding solderability were rarely studied. This work has successfully synthesized an aerogel derived from silver nanowires(AgNWs) using a liquid phase reduction method. It is found that the noble metal aerogels can be made into diverse aerogel preformed soldering sheets. The influence of bonding temperature(150-300 ℃), time(2-20 min), and pressure(5-20 MPa) on the joint strength of the AgNWs aerogel affixed to electroless nickel/silver copper plates were investigated. Additionally, the AgNWs aerogel displays almost the same shear strength for substrates of various sizes. In a word, this study presents a flux-free, high-strength, and adaptable soldering structural material.
