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Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei 被引量:2
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作者 Shicheng Su Nianqing Jin Xiaoli Wei 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期12-28,共17页
Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in... Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted. 展开更多
关键词 THinNinG Understory light environment Phoebe bournei Photosynthetic performance Growth performance
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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light
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作者 Pranav Gupta Silki Arora 《Journal of Transportation Technologies》 2024年第1期82-87,共6页
Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada... Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the U.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the U.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occurring during a yellow light at intersections. We believe this fairly simple solution will save lives, prevent injuries, reduce damage to public and private property, and decrease insurance costs. 展开更多
关键词 Traffic Accidents Yellow light Traffic light Signals inTERSECTION Crashes Collision Traffic Fatalities Traffic injuries Vehicles SAFETY Speed Limit Driving Pedestrians Bicyclists MOTORCYCLISTS Caution Line Yellow light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT internet of Things infrastructure Accident Reduction Driving Habits Stop Line Red light Jumping Pedestrian Safety Caution light Stopping at intersection Safety at intersections
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Photoperiod Mediates the Effects of Temperature and Light Intensity on the Proliferation of Ulva prolifera
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作者 JIANG Jianan YU Yanyan +2 位作者 CHEN Yili LI Yahe XU Nianjun 《Journal of Ocean University of China》 CAS CSCD 2024年第1期255-263,共9页
In order to study the complex effects of photoperiod,temperature,and light intensity on the spore maturation and release number of Ulva prolifera,we cultured thalli segment(2–3 mm)under three different photoperiods(L... In order to study the complex effects of photoperiod,temperature,and light intensity on the spore maturation and release number of Ulva prolifera,we cultured thalli segment(2–3 mm)under three different photoperiods(L:D=12:12,14:10 and 10:14),temperature(15℃(LT),25℃(MT)and 30℃(HT))and light intensity(100,200 and 400μmol m^(−2)s^(−1),noted as LL,ML and HL,respectively)conditions.Then the maturation time,spore release number and chlorophyll fluorescence were analyzed.The results suggested that:1)The spore maturation time was accelerated by higher temperature or higher light intensity from 62 h to 36 h,and changes in day length accelerated the spore maturation to a certain extent as compared with 12:12 light/dark cycle;2)Higher light intensity significantly decreased the chlorophyll fluorescence(Fv′/Fm′,NPQ,rETRmax andα)of the mature reproductive segment under 30℃with 12:12 light/dark cycle.But when in the other photoperiods(10:14 and 14:10 conditions),the inhibitory effects of high light intensity were alleviated significantly;3)The optimum condition for the spore maturation and release was 12:12 light/dark cycle,25℃,400μmol m^(−2)s^(−1),with both shorter and longer photoperiod reducing the spore release number;4)Higher light intensity significantly increased the spore release number under 25℃,but these effects were alleviated by 30℃treatment.This study is the first attempt to elucidate the coincidence effects of photoperiod,temperature and light intensity on the reproduction of Ulva,which would help to reveal the mechanism of the rapid proliferation of green tide. 展开更多
关键词 light intensity MATURATION PHOTOPERIOD REPRODUCTION TEMPERATURE Ulva prolifera
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Identifying drivers of urban landuse changes in the Wenchuan earthquake- affected area by using night-time light data
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作者 HUANG Tao DING Mingtao +2 位作者 GENG Dongxian GAO Zemin ZHENG Hao 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1140-1159,共20页
To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal... To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas.However,spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation data.This research,leveraging night-time light remote sensing imagery and land cover data,conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone areas.It introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these regions.To validate the proposed methods,the 2008 Wenchuan earthquake-affected area in China was selected as a representative study area.The results indicated that the average Digital Number(DN)values in socio-economically impacted areas showed a trend of rising,falling,and then rising again after the earthquake.DN values in three types of damaged areas including Type Ⅱ,Type Ⅲ,and Type Ⅳ exceeded pre-earthquake levels.The analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake,whereas factors such as slope,elevation,lithology,and faults had a stronger influence on urban land expansion after the earthquake.It can be seen that,in view of the differences in the natural conditions of regions for post-disaster reconstruction,the local government need to actively adjust and adapt to urban spatial planning,so as to leverage the scale effect of large-scale inputs of funds,facilities,human resources and other factors after the disaster,thus enhancing resilience and recovery efficiency in response to disaster impacts. 展开更多
关键词 Wenchuan earthquake Night-time lights Urban land Post-earthquake reconstruction
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Analyzing the Wind-Dominant Electricity Market under Coexistence of Regulated and Deregulated Power Trading
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作者 Yirui Li Dongliang Xiao +2 位作者 Haoyong Chen Weijun Cai Josue Campos do Prado 《Energy Engineering》 EI 2024年第8期2093-2127,共35页
Currently,both regulated and deregulated power trading exist in China’s power system,which has caused imbalanced funds in the electricity market.In this paper,a simulation analysis of the electricity market with wind... Currently,both regulated and deregulated power trading exist in China’s power system,which has caused imbalanced funds in the electricity market.In this paper,a simulation analysis of the electricity market with wind energy resources is conducted,and the calculation methods of unbalanced funds are investigated systematically.In detail,the calculation formulas of unbalanced funds are illustrated based on their definition,and a two-track electricity market clearing model is established.Firstly,the concept of the dual-track system is explained,and the specific calculation formulas of various types of unbalanced funds are provided.Next,considering the renewable energy consumption,the market clearing model based on DC power flow is constructed and solved;by combining fitting methods of mid-and long-term curves,the unbalanced funds are calculated based on clearing results and formulas. 展开更多
关键词 Dual-track system electricity market renewable energy unbalanced funds
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Hepatomegaly and jaundice as the presenting symptoms of systemic light-chain amyloidosis: A case report
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作者 Xu Zhang Fei Tang +2 位作者 Yan-Ying Gao De-Zhao Song Jing Liang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期550-556,共7页
BACKGROUND Light chain(AL)amyloidosis is a plasma cell dyscrasia characterized by the pathologic production and extracellular tissue deposition of fibrillar proteins derived from immunoglobulin AL fragments secreted b... BACKGROUND Light chain(AL)amyloidosis is a plasma cell dyscrasia characterized by the pathologic production and extracellular tissue deposition of fibrillar proteins derived from immunoglobulin AL fragments secreted by a clone of plasma cells,which leads to progressive dysfunction of the affected organs.The two most commonly affected organs are the heart and kidneys,and liver is rarely the dominant affected organ with only 3.9%of cases,making them prone to misdia-gnosis and missed diagnosis.CASE SUMMARY A 65-year-old woman was admitted with a 3-mo history of progressive jaundice and marked hepatomegaly.Initially,based on enhanced computed tomography scan and angiography,Budd-Chiari syndrome was considered and balloon dilatation of significant hepatic vein stenoses was performed.However,addi-tional diagnostic procedures,including liver biopsy and bone marrow-exami-nation,revealed immunoglobulin kapa AL amyloidosis with extensive liver involvement and hepatic vascular compression.The disease course was progre-ssive and fatal,and the patient eventually died 5 mo after initial presentation of symptoms.CONCLUSION AL amyloidosis with isolated liver involvement is very rare,and can be easily misdiagnosed as a vascular disease. 展开更多
关键词 JAUNDICE HEPATOMEGALY Liver amyloidosis Kappa light chain Pseudo-Budd-Chiari syndrome Case report
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Understanding the combustion behavior of electric bicycle batteries and unveiling its relationship with fire extinguishing
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作者 Zhanglong Yu Xueling Shen +6 位作者 Ran Xu Zheng Wang Zengming Wan Mingyang Chen Yi Cui Yanyan Fang Xiaoli Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期609-618,共10页
In this study,a detailed analysis of the combustion behaviors of the lithium iron phosphate(LFP)and lithium manganese oxide(LMO)batteries used in electric bicycles was conducted.This research included quantitative mea... In this study,a detailed analysis of the combustion behaviors of the lithium iron phosphate(LFP)and lithium manganese oxide(LMO)batteries used in electric bicycles was conducted.This research included quantitative measurements of the combustion duration,flame height,combustion temperature,heat release rate,and total heat release.The results indicated that LMO batteries exhibited higher combustion temperatures of 600–700°C,flame heights of 70–75 cm,a significantly higher heat release rate of40.1 k W(12 Ah),and a total heat release of 1.04 MJ(12 Ah)compared to LFP batteries with the same capacity.Based on these experimental results,a normalized total heat release(NORTHR)parameter was proposed,demonstrating good universality for batteries with different capacities.Utilizing this parameter,quantitative calculations and optimization of the extinguishing agent dosage were conducted for fires involving these two types of batteries,and the method was validated by extinguishing fires for these two types of battery packs with water-based extinguishing fluids. 展开更多
关键词 Combustion behavior Electric bicycle Lithium-ion battery fire extinguishing Normalized total heat release
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On a Heuristic Viewpoint Concerning the Conversion and Transformation of Sound into Light
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作者 Alessandro Rizzo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期363-385,共23页
In the study of Terrestrial Gamma-ray Flashes (TGFs) and Sonoluminescence, we observe parallels with larger cosmic events. Specifically, sonoluminescence involves the rapid collapse of bubbles, which closely resembles... In the study of Terrestrial Gamma-ray Flashes (TGFs) and Sonoluminescence, we observe parallels with larger cosmic events. Specifically, sonoluminescence involves the rapid collapse of bubbles, which closely resembles gravitational collapse in space. This observation suggests the potential formation of low-density quantum black holes. These entities, which might be related to dark matter, are thought to experience a kind of transient evaporation similar to Hawking radiation seen in cosmic black holes. Consequently, sonoluminescence could be a valuable tool for investigating phenomena typically linked to cosmic scale events. Furthermore, the role of the Higgs boson is considered in this context, possibly connecting it to both TGFs and sonoluminescence. This research could enhance our understanding of the quantum mechanics of black holes and their relation to dark matter on Earth. 展开更多
关键词 Planck Mass Gravity light PHONONS Phononic Field Vacuum Hydrodynamics SONOLUMinESCENCE Hawking Radiation Quantum Black Holes theory of General Singularity
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The Performance of Small Diameter Aluminum Light Support Structures Containing Handholes under Cyclic Fatigue
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作者 Cameron R. Rusnak Aya Al-Hamami Craig C. Menzemer 《Open Journal of Civil Engineering》 2024年第2期196-213,共18页
Aluminum light poles play a pivotal role in modern infrastructure, ensuring proper illumination along highways and in populated areas during nighttime. These poles typically feature handholes near their bases, providi... Aluminum light poles play a pivotal role in modern infrastructure, ensuring proper illumination along highways and in populated areas during nighttime. These poles typically feature handholes near their bases, providing access to electrical wiring for installation and maintenance. While essential for functionality, these handholes introduce a vulnerability to the overall structure, making them a potential failure point. Although prior research and analyses on aluminum light poles have been conducted, the behavior of smaller diameter poles containing handholes remains unexplored. Recognizing this need, a research team at the University of Akron undertook a comprehensive experimental program involving aluminum light poles with handholes containing welded inserts in order to gain a better understanding of their fatigue life, mechanical behavior, and failure mechanisms. The research involved testing seven large-scale aluminum light poles each 8-inch diameter, with two separate handholes. These handholes included a reinforcement that was welded to the poles. Finite Element Analysis (FEA), statistical analysis, and comparison analysis with their large counterparts (10-inch diameter) were used to augment the experimental results. The results revealed two distinct failure modes: progressive crack propagation leading to ultimate failure, and rupture of the pole near the weld initiation/termination site around the handhole. The comparison analysis indicated that the 8-inch diameter specimens exhibited an average fatigue life exceeding that of their 10-inch counterparts by an average of 30.7%. The experimental results were plotted alongside the fatigue detail classifications outlined in the Aluminum Design Manual (ADM), enhancing understanding of the fatigue detail category of the respective poles/handholes. 展开更多
关键词 light Pole Handhole Cyclic Fatigue Fatigue Analysis Finite Element Analysis Statistical Analysis
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Protective and Regenerative Efficacy of a Plant Oil-Based Day and Night Cream: Investigated by a Novel Approach to Reveal the Impact of Blue Light Irradiation on Epidermal Barrier Integrity and Lipid Matrix
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作者 Dorothee Dähnhardt Stephan Dähnhardt-Pfeiffer +4 位作者 Isabel Simon Dana Ditgen Inge Holland Dörte Segger Peter Staib 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第3期227-241,共15页
In recent years, the harmful effects of blue light (400 - 500 nm) as a component of visible light (400 - 700 nm) have increasingly gained attention of science, industry, and consumers. To date, only a few in vivo test... In recent years, the harmful effects of blue light (400 - 500 nm) as a component of visible light (400 - 700 nm) have increasingly gained attention of science, industry, and consumers. To date, only a few in vivo test methods for measuring the effects of blue light on the skin have been described. A direct measurement method that can detect the immediate effects of blue light on the epidermal permeability barrier (EPB) is still lacking. In this study, we present a new methodological approach that can be used to investigate both the protective and regenerative effects of cosmetic products on the EPB after blue light irradiation. In a study with 14 female volunteers, it was investigated whether the regular application of an O/W emulsion (day cream) can strengthen and protect the epidermal barrier against damaging blue light radiation of 60 J/cm2 (protective study design) and also whether a disruption of the epidermal barrier caused by blue light radiation is restored faster and better by the regular application of another O/W emulsion (night cream) than in product-untreated skin (regenerative study design). The two O/W emulsions are different in plant oil, active ingredient composition and texture. The seven-day treatment with the day cream initially led to a significant increase in the normalized lipid lamellae length in the intercellular space, whereas the irradiation with blue light after 24 hours led to a significant decrease in the lipid lamellae length in the untreated test area, but not in the area previously treated with the product. Regarding the regenerative study design, a two-day treatment with the night cream was able to restore a blue-light-induced decrease in lipid lamellae length in the intercellular space. In summary, with the study designs presented here, the protective and regenerative effect of two cosmetic products could be demonstrated for the first time on the integrity of the EPB after blue light irradiation and the data showed that the Lipbarvis® method is suitable for investigating the damaging effects of blue light on the EPB in vivo. 展开更多
关键词 Skin Care Blue light Irradiation Skin Barrier intercellular Lipid Lamellae Electron Microscopy
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The impacts of market reform on the market penetration of natural gas-fired electricity and renewable energy in China 被引量:4
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作者 Li-Jing Zhu Yan Li +2 位作者 Yan-Yan Tang Yao-Ming Li Qi Zhang 《Petroleum Science》 SCIE CAS CSCD 2017年第4期831-841,共11页
Natural gas-fired electricity(NGFE) is expected to play a more important role in the future due to its characteristics of low pollution, high efficiency and flexibility. However, its development in China is impeded by... Natural gas-fired electricity(NGFE) is expected to play a more important role in the future due to its characteristics of low pollution, high efficiency and flexibility. However, its development in China is impeded by its high regulation price compared with coal power. Market reform is therefore of vital importance to promote the penetration of NGFE. The objective of this study is to analyze the impacts of market reform and the renewable electricity(RE) subsidy policy on the promotion of NGFE and RE. A dynamic game-theoretic model is developed to analyze the interaction among the NG supplier, the power sector and the power grid. Three scenarios are proposed with different policies, including a fixed regulation price of NG and electricity, real-time pricing(RTP) of NG and electricity, and subsidy targeted at RE. The results show that:(1) market reform can sharply decrease the NG price and consequently promote the development of NGFE and RE;(2) subsidy targeted at RE not only promotes the penetration of NGFE and RE, but also increases the utilization ratio of renewables significantly;(3) market reform and the subsidy also enhance consumers’ welfare by reducing their power consumption expenditure. 展开更多
关键词 Natural gas-fired electricity Renewable electricity Real-time pricing Market reform Game-theoretic model
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Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases
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作者 Lifang Zhao Mingkai Zhang +4 位作者 Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai 《Neural Regeneration Research》 SCIE CAS 2025年第8期2373-2381,共9页
Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k... Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results. 展开更多
关键词 Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein NEURODEGENERATION neurofilament light chain plasma biomarkers single molecule array storage time tau
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The Effect of the Novel "light fertilizer" on the Environment Factor in High Tunnel and Growth of Brassica Chinensis 被引量:6
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作者 李文秀 周宁琳 +5 位作者 陈园园 王佳 朱晓玲 王振江 徐磊 冯伟民 《Agricultural Science & Technology》 CAS 2014年第12期2245-2248,共4页
[Objective] The aim was to study the properties of novel "light fertilizer", photo-conversion film, in order to evaluate its effect on the environmental factors and morphogenetic process of crops in the high tunnel.... [Objective] The aim was to study the properties of novel "light fertilizer", photo-conversion film, in order to evaluate its effect on the environmental factors and morphogenetic process of crops in the high tunnel. [Method] Photo-conversion film and Iongevous anti-dropping film were compared in terms of light, air and soil temperature utilizing the Facilities of leafy agriculture high tunnel intelligent monitoring system. Verifying the results by farmland experiment. [Result] Photo- conversion film indeed improved the light quality of high tunnel compared with the Iongevous anti- dripping film. The air and soil temperature was raised several degrees. Results of farmland experiment show that the average value of brassica chinensis fresh weight increased 19.15% compared to the control. [Conclusion] Photo-conversion film promotes more crop growth than Iongevous anti-dropping film due to improvement of light quality, air and soil temperature. 展开更多
关键词 Photo-conversion film Environmental factors light quality WARMinG light quality Yield increase Brassica chinensis
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Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury
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作者 Hang Yang Yulei Xia +4 位作者 Yue Ma Mingtong Gao Shuai Hou Shanshan Xu Yanqiang Wang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1900-1918,共19页
The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically revie... The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed.Here,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion injury.We further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms.Inhibition of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury. 展开更多
关键词 calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STinG pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein
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Effects of Light and Temperature on the Expression of the Lhcb2 Gene in Pea 被引量:5
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作者 孙钦秒 李良璧 +2 位作者 阎久胜 毛大璋 匡廷云 《Acta Botanica Sinica》 CSCD 2000年第3期258-262,共5页
An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting usi... An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting using special probe demonstrated that there existed one copy of Lhcb 2 in pea genome. RT_PCR and Northern blotting revealed the expression of Lhcb 2 which was regulated by light in a time_dependent expression manner. The Lhcb 2 gene didn't express untill 2 h after irradiated with white light. Low temperature (4 ℃) also affected the Lhcb 2 gene by decreasing half of its expression under 25 ℃. 展开更多
关键词 PEA Lhcb 2 gene light and temperature EXPRESSION
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Comparative Study of Photosynthetic and Fluorescence Characters of the Grape under High Temperature and High Light in Turpan 被引量:4
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作者 贾杨 廖康 +4 位作者 马微 江振斌 骆强伟 孙锋 伍国红 《Agricultural Science & Technology》 CAS 2015年第5期868-872,共5页
[Objective] The aim was to explore the photosynthetic characteristics of Turpan grapes under high temperature and strong light conditions. [Method] Using six grape varieties as experimental materials, the photosynthes... [Objective] The aim was to explore the photosynthetic characteristics of Turpan grapes under high temperature and strong light conditions. [Method] Using six grape varieties as experimental materials, the photosynthesis and fluorescence parameters of the grape varieties under high temperature and high light were determined. [Result] The results showed that Thompson Seedless showed strong selfprotection ability on the photosynthetic mechanism in the adversity, and lower photo inhibition on photosynthesis under high temperature and high light than other varieties in which Crimson Seedless was second place. Otherwise the damage on photosynthetic mechanism of Kyoho and Red Globe under the adversity environment is more dipper than the other varieties, and poor self-protection ability. [Conclusion]Thompson Seedless and Crimson Seedless had a strong adaptability for high temperature and strong light. But the adaptability of Kyoho and Red Globe were relatively poor. 展开更多
关键词 Turpan High temperature and high light GRAPE PHOTOSYNtheTIC FLUORESCENCE
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Effect of Light Intensity and Nutrient Availability on Clonal Growth and Clonal Morphology of the Stoloniferous Herb Halerpestes ruthenica 被引量:8
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作者 于飞海 董鸣 《Acta Botanica Sinica》 CSCD 2003年第4期408-416,共9页
In a greenhouse experiment plasticity of clonal growth and clonal morphology of the stoloniferous rosette herb Halerpestes nahenica Ovcz. in response to differing levels of light intensity and nutrient availability wa... In a greenhouse experiment plasticity of clonal growth and clonal morphology of the stoloniferous rosette herb Halerpestes nahenica Ovcz. in response to differing levels of light intensity and nutrient availability was studied. Total plant dry weight, leaf area of primary ramets, total number of ramets and of stolons, and total stolon length were significantly reduced, while specific internode length and specific petiole length significantly increased under deep shading (6.25% of high light intensity, 5.3% of full daylight) or under low nutrient availability. Under low nutrient availability, mean stolon internode length of H. ruthenica was significantly larger while branching intensity and number of ramets smaller than those under high nutrient availability. These responses are consistent with the foraging model of clonal plants, indicating that H. nahenica is able to forage nutrients through the plastic responses of clonal growth and clonal. morphology when it grows in heterogeneous environments. However, under deep shading, both mean stolon internode length and mean petiole length were significantly reduced, which disagrees with the findings of many other stoloniferous herbs in response to low or medium levels of shading (ca. 13%-75% of high light intensity, >10% of full daylight), suggesting that under deep shading stoloniferous herbs may not forage light through the plastic responses of spacer length. Many traits such as total plant dry weight, total number and length of stolons, total length of secondary and tertiary stolons. total number of ramets, leaf area of primary ramets and branching intensity were markedly influenced by the interaction effect of light intensity and nutrient availability. Under high light intensity nutrient availability affected these traits more pronouncedly, however under low light intensity nutrient availability either did not affect or affected less markedly on these traits, indicating that fight intensity had significant effect on nutrient foraging in H. nahenica. Under deep shading or low nutrient availability, H. ruthenica may increase its mean stolon internode length by means of thinning stolon internodes (i.e., an increase in specific internode length), which provides it with more chance to escape from resource-poor sites. 展开更多
关键词 clonal growth clonal morphology foraging behavior Halerpestes ruthenica light NUTRIENT PLASTICITY
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Effects of Salicylic Acid on Photosynthesis and Chlorophyll Fluorescence Characteristics of Fluecured Tobacco Leaf in Subdued Light 被引量:1
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作者 王辉 刘国顺 +2 位作者 云菲 张军 郭超超 《Agricultural Science & Technology》 CAS 2014年第1期33-38,共6页
[Objective] This study aimed to test whether salicylic acid (SA) can im-prove the physiological functions of flue-cured tobacco under subdued light condition, and to determine the mechanism of its action. [Method] T... [Objective] This study aimed to test whether salicylic acid (SA) can im-prove the physiological functions of flue-cured tobacco under subdued light condition, and to determine the mechanism of its action. [Method] The tobacco plants under subdued light were foliar-sprayed with 100 mg/L of SA. Then, the physiological in-dices such as plant fresh weight and dry weight, chlorophyl content, photosynthetic parameters and chlorophyl fluorescence parameters were measured. SPSS17.0 and Excellwere adopted for variance analysis and significance test. [Result] The leaf photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of tobacco plants in subdued light were al decreased while the intercellular CO2 con-centration (Ci) was increased, suggesting that non-stomatal limitation led to the de-crease of Pn under weak light intensity stress. SA released the inhibition of tobacco plant growth in weak light, as it elevated the leaf photosynthetic rate, the maximum photochemical efficiency of PSⅡ, potential activity of PSⅡ, effective photochemical efficiency of PSⅡ and photochemical quenching coefficient in weak light significant-ly, and reduced the non-photochemical quenching coefficient. [Conclusion] SA has significant effects on the photosynthetic characteristics of flue-cured tobacco in weak light, and it can improve the synthesis or distribution of photosynthesis product, and the efficiency of light energy, conducive to plant growth and development. 展开更多
关键词 Flue-cured tobacco Salicylic acid Subdued light PHOTOSYNtheSIS Chlorophyll fluorescence
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Photosynthetic Gas Exchange and Leaflet Movement of Robinia pseudoacacia in Relation to Changing Light Environments 被引量:2
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作者 张守仁 马克平 陈灵芝 《Acta Botanica Sinica》 CSCD 2002年第7期858-863,共6页
On the sunny days, there were little diurnal changes in both azimuth and directional angle for either sun_ or shade_leaflet. However, there existed a significant diurnal change in midrib angle that reflected movements... On the sunny days, there were little diurnal changes in both azimuth and directional angle for either sun_ or shade_leaflet. However, there existed a significant diurnal change in midrib angle that reflected movements regarding evasion of light stress around noon hours. On the cloudy day, a very little diurnal difference was found in azimuth, directional and midrib angle. It is suggested that changing light environment is the main factor for inducing leaflet movement of Robinia pseudoacacia , and the rhythmical movement does not attribute to the leaflet movement. Leaf orientation control test showed that the photosynthetic rate ( Pn ), stomatal conductance ( g s ) and transpiration ( Tr ) of the artificial fixed_leaflets were significantly lower than that of control_leaflets. And the leaf temperature ( Tl ) of the fixed leaflets significantly exceeded that of control_leaflets, which may attribute to the significant difference of light interception between the fixed and control_leaflets. The light_dependent leaflet movement is the morphological adjustment of maintaining optimal physiological status. 展开更多
关键词 Robinia pseudoacacia leaflet movement photosynthetic gas exchange light environment
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Impacts of bird abundance, activity height and light intensity on the number of birds captured by mist netting 被引量:2
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作者 邹发生 陈桂珠 杨琼芳 《Chinese Birds》 2010年第4期221-229,共9页
To understand better the impact on mist net capture rates of the activity height of birds, light intensity, bird richness and abundance, we compared data from mist nets and point counts at the Jianfengling Forest Area... To understand better the impact on mist net capture rates of the activity height of birds, light intensity, bird richness and abundance, we compared data from mist nets and point counts at the Jianfengling Forest Area, Hainan Island. Mist-nets were operated for a total of 7135 net-hours. A total of 587 individuals of 45 bird species were captured. The total mean capture rate was 8.6 ± 10.4 per 100 net-hours. A total of 4932 individuals of 107 bird species were recorded by visual observation alone and 7616 individuals of 120 species were recorded in a visual and aural combination. The Grey-cheeked Fulvetta (Alcippe morrisonia) was the most abundant species, accounting for 38.7% of total captures, 27.9% of visual observations and 22.2% of visual + aural observations. The capture number was correlated with the number observed. Thirty-one species were more likely to be captured than observed. Canopy species, such as members of the Corvidae and Dicruridae, were seldom captured. For all ground feeding species, the capture number was greater than that of observation. Some cryptic species, such as the Lesser Wren Babbler (Napothera epilepidota), Spotnecked Babbler (Stachyris striolata) and Cuckoo Owl (Glaucidium cuculoides) also had a higher relative capture rate than that of observations. There was a significant relationship between light intensity and the number of birds captured. 展开更多
关键词 activity height bird abundance light intensity mist nets point counts
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