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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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Effects of Different Light Qualities on the Growth Characteristics of Populus trinervis
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作者 Jiaqi Li Zhensheng Qiao +1 位作者 Dan Zong Chengzhong He 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期1043-1056,共14页
Populus trinervis is native to China and plays an irreplaceable role in maintaining the ecological balance of boreal and temperate forests.P.trinervis mainly grows in high-altitude areas.At present,there are limited s... Populus trinervis is native to China and plays an irreplaceable role in maintaining the ecological balance of boreal and temperate forests.P.trinervis mainly grows in high-altitude areas.At present,there are limited studies on the response of P.trinervis to different light qualities,so it is necessary to investigate the photosynthetic physiological changes of P.trinervis in different light environments.In our study,P.trinervis was grown for 8 months under light filtered by three different colored films.The three treatments were blue film,green film,and white plastic film.The effects of blue(B),green(G),and white(W)light on photosynthetic pigment content,absolute growth,photosynthetic parameters,soluble sugar content,and chlorophyll fluorescence parameters were studied,respectively.Compared to the Wtreatment,the chlorophyll a and b,carotenoids,total chlorophyll content(a+b),absolute growth of seedling height,net photosynthetic rate(PN),water use efficiency(WUE),total soluble sugars,sucrose,and nonphotochemical quenching(NPQ)of P.trinervis were significantly increased under B treatment.Meanwhile,chlorophyll a and b,carotenoids,total chlorophyll(a+b),transpiration rate(Tr),intercellular CO_(2) concentration(Ci),stomatal conductance(gs),absolute growth of seedling height and leaf length,reducing sugar,total soluble sugar content,and NPQ were significantly increased under G treatment.The results showed that the absolute growth and chlorophyll content of P.trinervis were increased under B light,while the sugar and photosynthetic parameters were increased under G light.Additional studies may look into how B light impacts absolute growth and promotional mechanisms,as well as how G light affects the accumulation of sugar levels. 展开更多
关键词 Blue light green light white light photosynthetic pigment soluble sugar
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Application of Smart Streetlights in Urban Road Lighting
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作者 Huiyan Yang 《Journal of Electronic Research and Application》 2024年第3期83-88,共6页
The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent year... The construction and installation of street lighting is an important element in the modernization of China’s cities.Besides,it also plays an important role in raising the living standards of the people.In recent years,with the technological and economic development,smart street lighting has gradually emerged.Key functions of smart street lighting include road illumination,cultural promotion,meteorological monitoring,public broadcasting,and 5G micro-base stations.The overall quality of smart street lighting construction directly impacts the effectiveness of urban development and the city’s comprehensive growth.This paper analyzes the concept of smart street lighting,its advantages and disadvantages,the functionalities of smart street light systems,and the application of smart street lighting in urban road illumination. 展开更多
关键词 Smart streetlights Urban street lighting LED streetlights
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人LIGHT和HSV-TK-EGFP基因共转染的MSCs抗肿瘤免疫的体内研究
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作者 陈芬 江千秋 +1 位作者 焦兰 唐澍 《实用癌症杂志》 2024年第11期1744-1748,共5页
目的研究与单纯疱疹病毒的糖蛋白D竞争结合单纯疱疹病毒进入介导物(herpes virus entry mediator,HVEM)的淋巴毒素类似物(homologous to lymphotoxins,exhibits inducible expression,and competes with HSV glycoprotein D for HVEM,a ... 目的研究与单纯疱疹病毒的糖蛋白D竞争结合单纯疱疹病毒进入介导物(herpes virus entry mediator,HVEM)的淋巴毒素类似物(homologous to lymphotoxins,exhibits inducible expression,and competes with HSV glycoprotein D for HVEM,a receptor expressed by T lymphocytes,LIGHT)基因和单纯疱疹病毒胸苷激酶(herpes simplex virus thymidine kinase,HSV-TK)基因共转染的骨髓间充质干细胞(mesenchymal stem cells,MSCs)在体内的抗肿瘤免疫功能。方法将pIRES2-LIGHT基因和HSV-TK-EGFP基因共转染小鼠骨髓间充质干细胞(MSCs/LT组),以转染空载体和转染HSV-TK-EGFP基因的骨髓间充质干细胞作对照。流式细胞仪检测LIGHT分子和HSV-TK-EGFP分子在稳定转染的骨髓间充质干细胞上的表达。体内迁移实验观察MSCs/LT在小鼠体内迁移情况。观察更昔洛韦注射前后MSCs/LT对荷瘤小鼠体内肿瘤的治疗作用。ELISA法检测小鼠肿瘤组织中IFN-γ,IL-2和IL-10的水平。结果流式细胞仪检测发现,MSCs/LT能稳定高表达LIGHT分子。MSCs/LT有特异地向肿瘤组织趋化的特性。MSCs/LT和MSCs/T有较好的抑制肿瘤生长的能力,但在更昔洛韦诱导后,MSCs/LT的抗肿瘤效应下降甚至消失。同时,MSCs/LT可促使T细胞进入肿瘤组织,并促进T细胞分泌IL-2、IFN-γ,抑制IL-10分泌(P<0.05)。结论共转染人LIGHT和HSV-TK-EGFP基因的骨髓间充质干细胞能稳定高表达LIGHT分子,能特异性地向荷瘤小鼠体内肿瘤组织趋化并抑制肿瘤的生长,这种体内抗肿瘤功能可能与促进T淋巴细胞IL-2、IFN-γ等细胞因子的分泌,改善局部免疫抑制环境有关。 展开更多
关键词 抗肿瘤免疫 间充质干细胞 转染 light基因 HSV-TK-EGFP基因
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An Investigation of Lighting Levels and Sleep Quality
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作者 Kathy Sexton-Radek Amina Mira 《Health》 2024年第9期794-800,共7页
Sleep quality in young adults is compromised. Instead of the recommended 7 hours, young adults’ schedule interruptions disturb sleep to a typical six and a half hours, with common disturbances in falling asleep and s... Sleep quality in young adults is compromised. Instead of the recommended 7 hours, young adults’ schedule interruptions disturb sleep to a typical six and a half hours, with common disturbances in falling asleep and staying asleep. Recent literature has identified an association between academic performance, negative mood state and low activity level in young adults with sleep disturbances. Young adulthood is a time for the installation of sleep health. Both individual and schedule impositions to the young adults’ sleep schedule are to be modified to obtain Sleep Health. Recent research has identified daytime light effects on sleep such as blue light from electronics as alerting and low level light for relaxation. The aim of this study was to identify sleep quality effects with varying light exposures. It was hypothesized that bright (>450 lux) light conditions would be considered focusing and low light (<220 lux) would be considered calming. We hypothesized that sleep quality would improve by 5% with the introduction of a calm light condition. Undergraduates from a small midwestern university were invited to participate in the study in exchange for a gift card. Six participants completed the study, two males, four females all between 21 - 24 years old. Both hypotheses were supported by qualitative analysis. 展开更多
关键词 light Sleep Quality lightING Sleep Disturbance
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CO_(2)-assisted oxidation dehydrogenation of light alkanes over metal-based heterogeneous catalysts
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作者 Yingbin Zheng Xinbao Zhang +4 位作者 Junjie Li Jie An Longya Xu Xiujie Li Xiangxue Zhu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期40-69,共30页
Light olefins are important platform feedstocks in the petrochemical industry,and the ongoing global economic development has driven sustained growth in demand for these compounds.The dehydrogenation of alkanes,derive... Light olefins are important platform feedstocks in the petrochemical industry,and the ongoing global economic development has driven sustained growth in demand for these compounds.The dehydrogenation of alkanes,derived from shale gas,serves as an alternative olefins production route.Concurrently,the target of realizing carbon neutrality promotes the comprehensive utilization of greenhouse gas.The integrated process of light alkanes dehydrogenation and carbon dioxide reduction(CO_(2)-ODH)can produce light olefins and realize resource utilization of CO_(2),which has gained wide popularity.With the introduction of CO_(2),coke deposition and metal reduction encountered in alkanes dehydrogenation reactions can be effectively suppressed.CO_(2)-assisted alkanes dehydrogenation can also reduce the risk of potential explosion hazard associated with O_(2)-oxidative dehydrogenation reactions.Recent investigations into various metal-based catalysts including mono-and bi-metallic alloys and oxides have displayed promising performances due to their unique properties.This paper provides the comprehensive review and critical analysis of advancements in the CO_(2)-assisted oxidative dehydrogenation of light alkanes(C2-C4)on metal-based catalysts developed in recent years.Moreover,it offers a comparative summary of the structural properties,catalytic activities,and reaction mechanisms over various active sites,providing valuable insights for the future design of dehydrogenation catalysts. 展开更多
关键词 light alkanes dehydrogenation CO_(2)utilization Metal-based catalysts light olefins Coupling reaction
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Light-Material Interactions Using Laser and Flash Sources for Energy Conversion and Storage Applications
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作者 Jung Hwan Park Srinivas Pattipaka +10 位作者 Geon-Tae Hwang Minok Park Yu Mi Woo Young Bin Kim Han Eol Lee Chang Kyu Jeong Tiandong Zhang Yuho Min Kwi-Il Park Keon Jae Lee Jungho Ryu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期468-514,共47页
This review provides a comprehensive overview of the progress in light-material interactions(LMIs),focusing on lasers and flash lights for energy conversion and storage applications.We discuss intricate LMI parameters... This review provides a comprehensive overview of the progress in light-material interactions(LMIs),focusing on lasers and flash lights for energy conversion and storage applications.We discuss intricate LMI parameters such as light sources,interaction time,and fluence to elucidate their importance in material processing.In addition,this study covers various light-induced photothermal and photochemical processes ranging from melting,crystallization,and ablation to doping and synthesis,which are essential for developing energy materials and devices.Finally,we present extensive energy conversion and storage applications demonstrated by LMI technologies,including energy harvesters,sensors,capacitors,and batteries.Despite the several challenges associated with LMIs,such as complex mechanisms,and high-degrees of freedom,we believe that substantial contributions and potential for the commercialization of future energy systems can be achieved by advancing optical technologies through comprehensive academic research and multidisciplinary collaborations. 展开更多
关键词 light light-material interaction NANOMATERIALS Energy conversion and storage devices
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A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope
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作者 Zhipeng Chen Xinyi Wang +3 位作者 Weihua Gui Jilin Zhu Chunhua Yang Zhaohui Jiang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期893-906,共14页
Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material... Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking efficiency.It has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)environment.Based on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is designed.Combined with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh environment.Based on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined space.Industrial experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting. 展开更多
关键词 Blast furnace(BF) burden surface extremely dim light industrial endoscope sensing imaging STARlight
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雷公藤多苷片对IgA肾病大鼠LIGHT-HVEM/LTβR通路的影响
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作者 王旭 方虹 +6 位作者 樊艳敏 季晗舒 宋珂 陈晨晨 卜继常 丁樱 宋纯东 《中国药理学通报》 CAS CSCD 北大核心 2024年第12期2277-2282,共6页
目的 基于炎症相关通路探讨雷公藤多苷片对IgA肾病大鼠肾脏的作用机制。方法 雄性SPF级SD大鼠,随机分为空白组、造模组。造模组采用联合“牛血清白蛋白+四氯化碳+脂多糖”建立IgA肾病大鼠模型。造模成功的大鼠随机分为模型组、泼尼松组... 目的 基于炎症相关通路探讨雷公藤多苷片对IgA肾病大鼠肾脏的作用机制。方法 雄性SPF级SD大鼠,随机分为空白组、造模组。造模组采用联合“牛血清白蛋白+四氯化碳+脂多糖”建立IgA肾病大鼠模型。造模成功的大鼠随机分为模型组、泼尼松组、雷公藤多苷片组,于第13周开始治疗组灌胃给药,给药4周后留取大鼠24 h尿液、血液、肾组织并检测尿红细胞数、24 h-UTP、BUN、Scr;ELISA检测血清IL-1β、TNF-α水平;HE染色观察各组大鼠肾组织病理学变化;Western blot及RT-PCR检测大鼠肾组织LIGHT、HVEM、LTβR蛋白及其mRNA的表达。结果 雷公藤多苷片明显降低IgA肾病大鼠尿红细胞数、24 h-UTP、BUN、Scr水平,改善肾组织病理,降低血清炎症因子IL-1β、TNF-α水平,降低肾组织中LIGHT、HVEM、LTβR蛋白及其mRNA表达水平。结论 雷公藤多苷片可能通过下调LIGHT-HVEM/LTβR信号通路,抑制免疫反应,减少炎症因子释放,从而减轻炎症反应,降低尿红细胞及尿蛋白,改善肾脏病理损伤,保护肾功能。 展开更多
关键词 雷公藤多苷片 IGA肾病 light-HVEM/LTβR 炎症 免疫反应 保护
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Controlled LED Lighting for Horticulture: A Review
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作者 Emmanouil D. Fylladitakis 《Open Journal of Applied Sciences》 CAS 2023年第2期175-188,共14页
As energy gradually becomes a more valuable commodity, the desire for reduced energy losses strengthens. Lighting is a critical field on this matter, as it accounts for a large percentage of the global electricity con... As energy gradually becomes a more valuable commodity, the desire for reduced energy losses strengthens. Lighting is a critical field on this matter, as it accounts for a large percentage of the global electricity consumption and modern lighting systems are greatly more efficient than incandescent, discharge, and fluorescent lights. Previous research has proven that plants do not require the entire visible spectrum but react only to specific wavelengths, making it possible to control their growth and yield via artificial lighting. The flexibility of control of Light Emitting Diode (LED) lights allows for the combination of great energy losses reduction and controlled plant growth, achieving the improvement of two major parameters in a single action. This review paper summarizes the current research on the effect different light wavelengths have on specific plant species and discusses the applications of LED lighting for horticulture, yield storage, and disease protection. 展开更多
关键词 Horticulture lighting Agriculture lighting Controlled LED light light Wavelength Effects light Spectrum VEGETABLES CROPS PHOTORECEPTORS
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Analysis of Current Research and Future Development Trends of Applying Solar Energy in Street Lighting
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作者 Liyan Zhang Qingying Zhou +1 位作者 Yueming Zhan Hu Guo 《Journal of Electronic Research and Application》 2024年第3期191-197,共7页
In the context of promoting green energy transition and addressing climate change globally,solar energy,as a clean and renewable energy source,has gradually become a hot topic for research.Solar streetlight systems re... In the context of promoting green energy transition and addressing climate change globally,solar energy,as a clean and renewable energy source,has gradually become a hot topic for research.Solar streetlight systems realize energy self-sufficiency and environment-friendly lighting by integrating photovoltaic power generation technology and efficient LED lighting technology.By comprehensively analyzing the current status of the application of solar streetlights at home and abroad,this paper discusses its technical advantages,market penetration,and challenges in its development.In terms of technical characteristics,this paper focuses on analyzing the key technologies such as energy conversion efficiency and intelligent control systems of solar streetlights. 展开更多
关键词 Solar streetlights Green energy Photovoltaic power generation LED lighting Intelligent control system
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基于CEEMDAN-VMD-TCN-lightGBM模型的水质预测研究
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作者 项新建 张颖超 +3 位作者 许宏辉 厉阳 王世乾 郑永平 《中国农村水利水电》 北大核心 2024年第3期86-95,共10页
针对目前水质预测模型中因为数据本身的复杂性、在信号处理过程中存在的噪声干扰以及分解深度不够导致单一分解难以全面捕捉信号非线性特征的问题,提出了一种基于二次分解的水质预测模型。该模型采用完全自适应噪声集合经验模态分解(CEE... 针对目前水质预测模型中因为数据本身的复杂性、在信号处理过程中存在的噪声干扰以及分解深度不够导致单一分解难以全面捕捉信号非线性特征的问题,提出了一种基于二次分解的水质预测模型。该模型采用完全自适应噪声集合经验模态分解(CEEMDAN)对原始数据进行分解,再利用变分模态分解(VMD)对熵值最高的模态分量进行二次分解,最终将处理后的时间序列输入到TCN-lightGBM多特征预测模型中。同时,采用麻雀算法(SSA)对预测模型进行优化。以山东省玉符河水质为例,本模型的均方根误差(RMSE)是0.1053,平均绝对误差(MAE)是0.0815,决定系数(R2)是0.9471,与GRU、LSTM、LightGBM、TCN等当下较为流行的模型的预测指标进行比较。结果显示,在R2上本模型提升了53.04%、70.41%、66.07%、65.20%等,在RMSE上减少了62.76%、65.50%、64.93%、64.80%等,在MAE上降低了62.76%、66.24%、63.80%、65.24%等。由此可知,基于CEEMDAN-VMD-TCN-lightGBM的模型具有更好的预测性能、泛化能力和捕捉信号非线性特征的能力。 展开更多
关键词 二次分解 TCN lightGBM 多特征预测 水质预测 麻雀算法
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Light-emitting-diode induced retinal damage and its wavelength dependency in vivo 被引量:5
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作者 Yu-Man Shang Gen-Shuh Wang +2 位作者 David H.Sliney Chang-Hao Yang Li-Ling Lee 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第2期191-202,共12页
AIM: To examine light-emitting-diode(LED)-induced retinal neuronal cell damage and its wavelength-driven pathogenic mechanisms.METHODS: Sprague-Dawley rats were exposed to blue LEDs(460 nm),green LEDs(530 nm),... AIM: To examine light-emitting-diode(LED)-induced retinal neuronal cell damage and its wavelength-driven pathogenic mechanisms.METHODS: Sprague-Dawley rats were exposed to blue LEDs(460 nm),green LEDs(530 nm),and red LEDs(620 nm).Electroretinography(ERG),Hematoxylin and eosin(H&E) staining,transmission electron microscopy(TEM),terminal deoxynucleotidyl transferase d UTP nick end labeling(TUNEL),and immunohistochemical(IHC) staining,Western blotting(WB) and the detection of superoxide anion(O2^-·),hydrogen peroxide(H2O2),total iron,and ferric(Fe^3+) levels were applied.RESULTS: ERG results showed the blue LED group induced more functional damage than that of green or red LED groups.H&E staining,TUNEL,IHC,and TEM revealed apoptosis and necrosis of photoreceptors and RPE,which indicated blue LED also induced more photochemical injury.Free radical production and iron-related molecular marker expressions demonstrated that oxidative stress and ironoverload were associated with retinal injury.WB assays correspondingly showed that defense gene expression was up-regulated after the LED light exposure with a wavelength dependency.CONCLUSION: The study results indicate that LED bluelight exposure poses a great risk of retinal injury in awake,task-oriented rod-dominant animals.The wavelengthdependent effect should be considered carefully when switching to LED lighting applications. 展开更多
关键词 retinal light injury LED light injury bluelight injury iron light injury mechanisms oxidative stress
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Public health importance of light intensity physical activity 被引量:1
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作者 Robert Ross Ian Janssen Mark S.Tremblay 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期674-675,共2页
1.Light intensity physical activity(PA)benefits health PA guidelines worldwide recommend that adults accumulate 150 min of moderate intensity or 75 min of vigorous intensity PA(moderate-to-vigorous PA(MVPA))weekly to ... 1.Light intensity physical activity(PA)benefits health PA guidelines worldwide recommend that adults accumulate 150 min of moderate intensity or 75 min of vigorous intensity PA(moderate-to-vigorous PA(MVPA))weekly to achieve health benefits.1-3 Absent from these guidelines are recommendations for light intensity PA(LPA,e.g.,walking at a leisurely pace of 3 km/h or less,equivalent to 1.5-2.9 metabolic equivalents). 展开更多
关键词 INTENSITY light BENEFITS
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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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Model prediction of inactivation of Aeromonas salmonicida grown on poultry in situ by intense pulsed light 被引量:1
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作者 Jingwen Wang Zhenzhen Ning +2 位作者 Yifan Chen Xinglian Xu Huhu Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1011-1017,共7页
The aim of this study was to evaluate the factors influencing the inactivation effect of intense pulsed light(IPL)on Aeromonas salmonicida grown on chicken meat and skin,and to further develop prediction models of ina... The aim of this study was to evaluate the factors influencing the inactivation effect of intense pulsed light(IPL)on Aeromonas salmonicida grown on chicken meat and skin,and to further develop prediction models of inactivation.In this work,chicken meat and skin inoculated with meat-borne A.salmonicida isolates were subjected to IPL treatments under different conditions.The results showed that IPL had obvious bactericidal effect in the chicken skin and thickness groups when the treatment voltage and time were 7 V combined with 5 s.In addition,the lethality curves of A.salmonicida were fitted under IPL conditions of 3.5-7.5 V.The comparison of statistical parameters revealed that the Weibull model could best fit the mortality curves and could accurately predict the mortality dynamic of A.salmonicida grown on chicken skin.And further a secondary model between the scale factor b and the treatment voltage in Weibull model was established using linear equations,which determined that the secondary model could accurately predict the inactivation of A.salmonicida.This study provides a theoretical basis for future prediction models of Aeromonas,and also provides new ideas for sterilization approaches of meat-borne Aeromonas. 展开更多
关键词 Aeromonas salmonicida Intense pulsed light INACTIVATION Chicken meat MODEL
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基于LightGBM的智能可穿戴设备用户行为预测
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作者 肖新元 《移动信息》 2024年第2期200-202,共3页
智能可穿戴设备产生的大量数据是人类宝贵的数字资源。使用开放数据集和主流数据分析工具,如可进行快速模型开发的PyCaret模块,有助于人们进行数据挖掘工作,且不被细节所困扰。作为Kaggle竞赛爱好者的常用工具,LightGBM分类器对用户行... 智能可穿戴设备产生的大量数据是人类宝贵的数字资源。使用开放数据集和主流数据分析工具,如可进行快速模型开发的PyCaret模块,有助于人们进行数据挖掘工作,且不被细节所困扰。作为Kaggle竞赛爱好者的常用工具,LightGBM分类器对用户行为的预测表现优异,对此文中的研究结果也得到验证。 展开更多
关键词 GBDT lightGBM PyCaret 机器学习
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CAEFusion: A New Convolutional Autoencoder-Based Infrared and Visible Light Image Fusion Algorithm 被引量:1
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作者 Chun-Ming Wu Mei-Ling Ren +1 位作者 Jin Lei Zi-Mu Jiang 《Computers, Materials & Continua》 SCIE EI 2024年第8期2857-2872,共16页
To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed... To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed.The region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map.A multi-scale convolution attention module is suggested to enhance the communication of feature information.At the same time,the feature transformation module is introduced to learn more robust feature representations,aiming to preserve the integrity of image information.This study uses three available datasets from TNO,FLIR,and NIR to perform thorough quantitative and qualitative trials with five additional algorithms.The methods are assessed based on four indicators:information entropy(EN),standard deviation(SD),spatial frequency(SF),and average gradient(AG).Object detection experiments were done on the M3FD dataset to further verify the algorithm’s performance in comparison with five other algorithms.The algorithm’s accuracy was evaluated using the mean average precision at a threshold of 0.5(mAP@0.5)index.Comprehensive experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks. 展开更多
关键词 Image fusion deep learning auto-encoder(AE) INFRARED visible light
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Generation of structured light beams with polarization variation along arbitrary spatial trajectories using tri-layer metasurfaces 被引量:2
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作者 Tong Nan Huan Zhao +3 位作者 Jinying Guo Xinke Wang Hao Tian Yan Zhang 《Opto-Electronic Science》 2024年第5期1-11,共11页
Conventionally,the spatially structured light beams produced by metasurfaces primarily highlight the polarization modulation of the beams propagating along the optical axis or the beams'spatial transmission trajec... Conventionally,the spatially structured light beams produced by metasurfaces primarily highlight the polarization modulation of the beams propagating along the optical axis or the beams'spatial transmission trajectory.In particular,along the optical axis,the polarization state is either constant or varies continuously in each output plane.Here,we develop innovative spatially structured light beams with continually changing polarization along any arbitrary spatial transmission trajectories.With tri-layer metallic metasurfaces,the geometric characteristics of each layer structure can be adjusted to modulate the phase and polarization state of the incident terahertz(THz)wave.The beam will converge to the predefined trajectory along several paths to generate a Bessel-like beam with longitudinal polarization changes.We demonstrate the versatility of the approach by designing two THz-band structured light beams with varying polarization states along the spatial helical transmission trajectory.Continuous linear polarization changes and linear polarization to right circular polarization(RCP)and back to linear polarization changes are realized respectively.The experimental results are basically consistent with the simulated results.Our proposal for arbitrary trajectory structured light beams with longitudinally varying polarization offers a practical method for continuously regulating the characteristics of spatial structured light beams with non-axial transmission.This technique has potential uses in optical encryption,particle manipulation,and biomedical imaging. 展开更多
关键词 structured light beam tri-layer metallic metasurface longitudinal polarization non-axial transmission
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Miscibility of light oil and flue gas under thermal action 被引量:1
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作者 XI Changfeng WANG Bojun +7 位作者 ZHAO Fang HUA Daode QI Zongyao LIU Tong ZHAO Zeqi TANG Junshi ZHOU You WANG Hongzhuang 《Petroleum Exploration and Development》 SCIE 2024年第1期164-171,共8页
The miscibility of flue gas and different types of light oils is investigated through slender-tube miscible displacement experiment at high temperature and high pressure.Under the conditions of high temperature and hi... The miscibility of flue gas and different types of light oils is investigated through slender-tube miscible displacement experiment at high temperature and high pressure.Under the conditions of high temperature and high pressure,the miscible displacement of flue gas and light oil is possible.At the same temperature,there is a linear relationship between oil displacement efficiency and pressure.At the same pressure,the oil displacement efficiency increases gently and then rapidly to more than 90% to achieve miscible displacement with the increase of temperature.The rapid increase of oil displacement efficiency is closely related to the process that the light components of oil transit in phase state due to distillation with the rise of temperature.Moreover,at the same pressure,the lighter the oil,the lower the minimum miscibility temperature between flue gas and oil,which allows easier miscibility and ultimately better performance of thermal miscible flooding by air injection.The miscibility between flue gas and light oil at high temperature and high pressure is more typically characterized by phase transition at high temperature in supercritical state,and it is different from the contact extraction miscibility of CO_(2) under conventional high pressure conditions. 展开更多
关键词 light oil flue gas flooding thermal miscible flooding miscible law distillation phase transition minimum miscible pressure minimum miscible temperature
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