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Single-cell profiling reveals Müller glia coordinate retinal intercellular communication during light/dark adaptation via thyroid hormone signaling
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作者 Min Wei Yanping Sun +10 位作者 Shouzhen Li Yunuo Chen Longfei Li Minghao Fang Ronghua Shi Dali Tong Jutao Chen Yuqian Ma Kun Qu Mei Zhang Tian Xue 《Protein & Cell》 SCIE CSCD 2023年第8期603-617,共15页
Light adaptation enables the vertebrate visual system to operate over a wide range of ambient illumination.Regulation of phototransduction in photoreceptors is considered a major mechanism underlying light adaptation.... Light adaptation enables the vertebrate visual system to operate over a wide range of ambient illumination.Regulation of phototransduction in photoreceptors is considered a major mechanism underlying light adaptation.However,various types of neurons and glial cells exist in the retina,and whether and how all retinal cells interact to adapt to light/dark conditions at the cellular and molecular levels requires systematic investigation.Therefore,we utilized single-cell RNA sequencing to dissect retinal cell-type-specific transcriptomes during light/dark adaptation in mice.The results demonstrated that,in addition to photoreceptors,other retinal cell types also showed dynamic molecular changes and specifically enriched signaling pathways under light/dark adaptation.Importantly,Müller glial cells(MGs)were identified as hub cells for intercellular interactions,displaying complex cell‒cell communication with other retinal cells.Furthermore,light increased the transcription of the deiodinase Dio2 in MGs,which converted thyroxine(T4)to active triiodothyronine(T3).Subsequently,light increased T3 levels and regulated mitochondrial respiration in retinal cells in response to light conditions.As cones specifically express the thyroid hormone receptor Thrb,they responded to the increase in T3 by adjusting light responsiveness.Loss of the expression of Dio2 specifically in MGs decreased the light responsive ability of cones.These results suggest that retinal cells display global transcriptional changes under light/dark adaptation and that MGs coordinate intercellular communication during light/dark adaptation via thyroid hormone signaling. 展开更多
关键词 single cell Müller glial cells intercellular communication light/dark adaptation thyroid hormone signaling
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Ecological adaptation of Eupatorium adenophorum populations to light intensity 被引量:6
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作者 孙晓玉 陆兆华 +2 位作者 李鹏辉 姜骑山 梁震 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期116-120,共5页
Eupatorium adenophorum is one of main invasive plants in China and has caused great economic losses. A study was conducted to determine the biomass allocation, leaf morphology and growth response of E. adenophorum see... Eupatorium adenophorum is one of main invasive plants in China and has caused great economic losses. A study was conducted to determine the biomass allocation, leaf morphology and growth response of E. adenophorum seedlings that grew under five different intensities (relative irradiances RI 10%, 20 %, 30%, 55%, 100%) for 14 months. Results reveal that the species shows typical leaf morphological adaptation to different light conditions. The total biomass of seedlings increased with the increase of light intensity from 10% to 55% RI but decreased at RI 100% (full sunlight). Height growth increased with the increase of light intensity from 10% to 30% RI but decreased when light intensity was over 30% RI. At low light levels, plants enhanced light availability by means of increasing biomass allocation to leaves and formation of larger, thinner leaves with high specific leaf area (SLA), leading to a high leaf area ratio (LAR) and high stem strips length (SSL). The mean relative growth rate (RGR) of the plant increased with the light intensity increase and attained the maximum at 55% RI. The growth of seedlings at 30%-55% RI was much better than that at full light condition. This might be an adaptive strategy that supports the vigorous invasiveness of this species, because a high-shaded canopy could prevent other plant species from surviving and growing. This study indicates that E. adenophorum could adapt to different light conditions, especially to low light habit. This can explain its greater invasiveness. 展开更多
关键词 Ecological adaptation Eupatorium adenophorum INVASIVENESS light intensity
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Recent advances in the dark adaptation investigations 被引量:1
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作者 Guo-Qing Yang Tao Chen +1 位作者 Ye Tao Zuo-Ming Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第6期1245-1252,共8页
Dark adaptation is a highly sensitive neural function and may be the first symptom of many status including the physiologic and pathologic entity, suggesting that it could be instrumental for diagnose. However, shortc... Dark adaptation is a highly sensitive neural function and may be the first symptom of many status including the physiologic and pathologic entity, suggesting that it could be instrumental for diagnose. However, shortcomings such as the lack of standardized parameters, the long duration of examination, and subjective&#x000a0;randomness would substantially impede the use of dark adaptation in clinical work. In this review we summarize the recent research about the dark adaptation, including two visual cycles-canonical and cone-specific visual cycle, affecting factors and the methods for measuring dark adaptation. In the opinions of authors, intensive investigations are needed to be done for the widely use of this significant visual function in clinic. 展开更多
关键词 dark adaptation visual cycle pigment regeneration adaptometer
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A Research on Darkness Adaptation of Drivers
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作者 马国忠 张殿业 金键 《Journal of Modern Transportation》 2001年第1期101-103,共3页
This paper presents the results of darkness adaptationtest for drivers. It is shown that there is a significant difference ( p <0.05)in their darkness adaptation ability between the drivers in accident group and ... This paper presents the results of darkness adaptationtest for drivers. It is shown that there is a significant difference ( p <0.05)in their darkness adaptation ability between the drivers in accident group and non-accident group. It is further revealed that the accident rate of the drivers with darkness adaptation time ≤10 s is 2.6%, while that with darkness adaptation time >10 s is 7.3%, implying that the high accident rate of the drivers in accident group might be caused by their longer darkness adaptation time. 展开更多
关键词 SAFETY traffic accident darkness adaptation safe driving speed
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Optimum Dark Adaptation Period for Evaluating the Maximum Quantum Efficiency of Photosystem II in Ozone-Exposed Rice Leaves
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作者 Hiroki Hiroki Kobayakawa Katsu Imai 《American Journal of Plant Sciences》 2013年第9期1750-1757,共8页
Because the transient O3 injury of leaves is lost with time, the evaluation of O3 effect on the maximum quantum efficiency of PSII (Fv/Fm) is difficult. Thus, the authors examined Fv/Fm in rice leaves exposed to diffe... Because the transient O3 injury of leaves is lost with time, the evaluation of O3 effect on the maximum quantum efficiency of PSII (Fv/Fm) is difficult. Thus, the authors examined Fv/Fm in rice leaves exposed to different O3 concentrations (0, 0.1, and 0.3 cm3·m-3, expressed as O0, O0.1, and O0.3) under different dark adaptation periods (0, 1, 5, 10, 20, and 30 min, expressed as D0, D1, D5, D10, D20, and D30) to ascertain its optimum time span. Fv/Fm was inhibited by O3;however in the O0 and O0.1 plants, it recovered during dark adaptation. In the O0.3 plants, Fv/Fm decreased gradually with time. F0 was found to be increased by O3, and it increased further in the O0.3 plants during dark adaptation. Under a high light intensity, Fm was decreased by O3, and the O3-induced damage to Fv/Fm was therefore more pronounced. However, the sensitivity of 展开更多
关键词 dark-adapted State ORYZA SATIVA OZONE Stress PHOTOSYSTEM II Quantum Efficiency
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A Topological Magueijo-Smolin Varying Speed of Light Theory, the Accelerated Cosmic Expansion and the Dark Energy of Pure Gravity 被引量:8
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作者 Mohamed Salah El Naschie Leila Marek-Crnjac +1 位作者 Mohamed Atef Helal Ji-Huan He 《Applied Mathematics》 2014年第12期1780-1790,共11页
The paper presents a detailed analysis of ordinary and dark energy density of the cosmos based on two different but complimentary theories. First, and starting from the concept of the speed of light being an average o... The paper presents a detailed analysis of ordinary and dark energy density of the cosmos based on two different but complimentary theories. First, and starting from the concept of the speed of light being an average over multi-fractals, we use Magueijo-Smolin’s ingenious revision of Einstein’s special relativity famous formula E = mc2 to a doubly special formula which includes the Planck energy as invariant to derive the ordinary energy density E(O) = mc2/22 and the dark energy density E(D) = mc2(21/22) wheremis the mass andcis the speed of light. Second we use the topological theory of pure gravity to reach the same result thus confirming the correctness of the theory of varying speed of light as well as the COBE, WMAP and Type 1a supernova cosmological measurements. 展开更多
关键词 dark ENERGY QUANTUM GRAVITY VARYING Speed of light THEORY ENERGY of QUANTUM Wave QUANTUM Non-Demolition
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Adaptive illumination light source for online machine vision inspection of tin steel strips 被引量:3
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作者 PENG Tiegen HE Yonghui 《Baosteel Technical Research》 CAS 2013年第4期25-28,共4页
The different reflection characteristics of the surface of tin steel strips and the different speeds of the tinning line demand an adaptive illumination light source for online machine vision inspection. This light so... The different reflection characteristics of the surface of tin steel strips and the different speeds of the tinning line demand an adaptive illumination light source for online machine vision inspection. This light source can be integrated with a time delay integration charge-coupled device (TDI CCD ) to capture the images of moving objects and facilitate inspection of the surface quality of tin steel strips. On-site application show the effectiveness of the TDI camera with the adaptive illumination light source in detecting the surface defects on tin steel strips of three different materials and with different tin coating weights. 展开更多
关键词 adaptive illumination light source tin steel strip TDI camera
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The Light-Dark Dual Universe for the Big Bang and Dark Energy 被引量:2
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作者 Ding-Yu Chung Volodymyr Krasnoholovets 《Journal of Modern Physics》 2013年第7期77-84,共8页
In the proposed light-dark dual universe, the light universe is the observable universe with light and kinetic energy that fueled the Big Bang, and the dark universe without light and kinetic energy has been observed ... In the proposed light-dark dual universe, the light universe is the observable universe with light and kinetic energy that fueled the Big Bang, and the dark universe without light and kinetic energy has been observed as dark energy since about 9 billion years after the Big Bang. The light-dark dual universe started from the zero-energy universe through the four-stage cyclic transformation. Emerging from the zero-energy universe, the four-stage transformation consists of the 11D (dimensional) positive-negative energy dual membrane universe, the 10D positive-negative energy dual string universe, the 10D positive-negative energy dual particle universe, and the 4D (light)-variable D (dark) positive-negative energy dual particle asymmetrical universe. The transformation can then be reversed back to the zero-energy universe through the reverse four-stage transformation. The light universe is an observable four-dimensional universe started with the inflation and the Big Bang, and the dark universe is a variable dimensional universe from 10D to 4D. The dark universe could be observed as dark energy only when the dark universe turned into a four-dimensional universe. The four-stage transformation explains the four force fields in our universe. The theoretical calculated percentages of dark energy, dark matter, and baryonic matter are 72.8. 22.7, and 4.53, respectively, in nearly complete agreement with observed 72.8, 22.7, and 4.56, respectively. According to the calculation, dark energy started in 4.47 billion years ago in agreement with the observed 4.71 ± 0.98 billion years ago. The zero-energy cyclic universe is based on the space-object structures. 展开更多
关键词 Cosmology light UNIVERSE dark UNIVERSE DUAL UNIVERSE Big Bang Inflation Zero-Energy Cyclic UNIVERSE dark ENERGY dark MATTER Baryonic MATTER Force Fields
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The Looped Light of the Triple-Slit Real Experiment as a Confirmation for the Extra Dimensions of Quantum Spacetime and the Reality of Dark Energy 被引量:1
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作者 Mohamed S. El Naschie 《Optics and Photonics Journal》 2017年第2期19-26,共8页
Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence... Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence of extra fractal dimensions and consequently of real dark energy density in full agreement with previous analysis as well as accurate measurements and observations of COBE, WMAP, and the type 1a supernova. 展开更多
关键词 Looped light dark Energy E-INFINITY Cantorian SPACETIME Peano-Hilbert SPACETIME Model Triple-Slit EXPERIMENT Fractal Kaluza-Klein Theory WMAP Type La Supernova
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Research on color image matching method based on feature point compensation in dark light environment 被引量:1
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作者 唐华鹏 QIN Danyang +2 位作者 YAN Mengying YANG Jiaqiang ZHANG Gengxin 《High Technology Letters》 EI CAS 2023年第1期78-86,共9页
Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching ... Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching is widely used in target recognition and tracking,indoor positioning and navigation.Local features missing,however,often occurs in color images taken in dark light,making the extracted feature points greatly reduced in number,so as to affect image matching and even fail the target recognition.An unsharp masking(USM)based denoising model is established and a local adaptive enhancement algorithm is proposed to achieve feature point compensation by strengthening local features of the dark image in order to increase amount of image information effectively.Fast library for approximate nearest neighbors(FLANN)and random sample consensus(RANSAC)are image matching algorithms.Experimental results show that the number of effective feature points obtained by the proposed algorithm from images in dark light environment is increased,and the accuracy of image matching can be improved obviously. 展开更多
关键词 dark light environment unsharp masking(USM) denoising model feature point compensation fast library for approximate nearest neighbor(FLANN) random sample consensus(RANSAC)
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A Unified Newtonian-Relativistic Quantum Resolution of the Supposedly Missing Dark Energy of the Cosmos and the Constancy of the Speed of Light 被引量:3
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作者 M.S.El Naschie 《International Journal of Modern Nonlinear Theory and Application》 2013年第1期43-54,共12页
Time dilation, space contraction and relativistic mass are combined in a novel fashion using Newtonian dynamics. In this way we can surprisingly retrieve an effective quantum gravity energy-mass equation which gives t... Time dilation, space contraction and relativistic mass are combined in a novel fashion using Newtonian dynamics. In this way we can surprisingly retrieve an effective quantum gravity energy-mass equation which gives the accurate experimental value of vacuum density. Furthermore Einstein’s equation of special relativity E = mc2, where m is the mass and c is the velocity of light developed assuming smooth 4D space time is transferred to a rugged Calabi-Yau and K3 fuzzy Kahler manifolds and revised to become E=(mc2)/(22), where the division factor 22 maybe interpreted as the compactified bosonic dimensions of Veneziano-Nambu strings. The result is again an accurate effective quantum gravity energy-mass relation akin to the one found using Newtonian dynamics which correctly predicts that 95.4915028% of the energy in the cosmos is the hypothetical missing dark energy. The agreement with WMAP and supernova measurements is in that respect astounding. In addition different theories are used to check the calculations and all lead to the same quantitative result. Thus the theories of varying speed of light, scale relativity, E-infinity theory, M-theory, Heterotic super strings, quantum field in curved space time, Veneziano’s dual resonance model, Nash Euclidean embedding and super gravity all reinforce, without any reservation, the above mentioned theoretical result which in turn is in total agreement with the most sophisticated cosmological measurements which was deservingly awarded the 2011 Nobel Prize in Physics. Finally and more importantly from certain viewpoints, we reason that the speed of light is constant because it is a definite probabilistic expectation value of a variable velocity in a hierarchical fractal clopen, i.e. closed and open micro space time. 展开更多
关键词 dark Energy Homology of Fuzzy Kahler Betti Numbers Heterotic Strings Revised Special Relativity Speed of light as a Probabilistic Expectation Value
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Calculating the Exact Experimental Density of the Dark Energy in the Cosmos Assuming a Fractal Speed of Light
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作者 Mohamed S. El Naschie 《International Journal of Modern Nonlinear Theory and Application》 2014年第1期1-5,共5页
Fractal speed of light theory is a variation of Magueijo-Smolin varying speed of light (VSL) theoretical modification of Einstein’s energy mass relation. We use this theory to derive an exact value for the missing da... Fractal speed of light theory is a variation of Magueijo-Smolin varying speed of light (VSL) theoretical modification of Einstein’s energy mass relation. We use this theory to derive an exact value for the missing dark energy which is found to be in astonishing agreement with the latest result of the WMAP measurement and the independent supernova analysis. Thus while Einstein’s formula predicts 95.5% more energy than found in highly precise astrophysical measurement, our VSL- based calculation indicates an exact theoretical value of only 4.508497% real energy. Consequently, the exact conjectured missing dark energy must be 95.491502%. By any standards, this is an astounding confirmation for both the cosmological measurement and the VSL theory. 展开更多
关键词 Nonlinear Dynamics Fractals dark Energy Quantum Gravity Varying Speed of light Theory
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Differential gene expression in the body wall of the sea cucumber(Apostichopus japonicus)under strong lighting and dark conditions
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作者 ZHANG Libin FENG Qiming +4 位作者 SUN Lina FANG Yan XU Dongxue ZHANG Tao YANG Hongsheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第5期54-66,共13页
Sea cucumber, Apostichopus japonicus is very sensitive to light changes. It is important to study the influence of light on the molecular response of A. japonicus. In this study, RNA-seq provided a general overview of... Sea cucumber, Apostichopus japonicus is very sensitive to light changes. It is important to study the influence of light on the molecular response of A. japonicus. In this study, RNA-seq provided a general overview of the gene expression profiles of the body walls of A. japonicus exposed to strong light("light"), normal light("control") and fully dark("dark") environment. In the comparisons of "control" vs. "dark", "control" vs. "light" and "dark" vs."light", 1 161, 113 and 1 705 differentially expressed genes(DEGs) were identified following the criteria of|log2 ratio|≥1 and FDR≤0.001, respectively. Gene ontology analysis showed that "cellular process" and "binding"enriched the most DEGs in the category of "biological process" and "molecular function", while "cell" and "cell part" enriched the most DEGs in the category of "cellular component". And the DEGs were mapped to 214, 41 and229 pathways in the Kyoto Encyclopedia of Genes and Genomes database, and 51, 2 and 57 pathways were significantly enriched, respectively. Light-specific DEGs identified in this study will be important targets for further investigation to establish the biochemical mechanisms involved in the adaption of this sea cucumber to changes in the level of environmental light. 展开更多
关键词 sea cucumber Apostichopus japonicus gene expression dark light body wall
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Looped Light on Dark Energy
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作者 Mohamed S. El Naschie 《Journal of Quantum Information Science》 2017年第2期43-47,共5页
We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of q... We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of quantum mechanics. The outcome of the sophisticated experiment revealed the looped path of light on the quantum scale and consequently the Peano-Hilbert geometry of spacetime, ergo its fractal-Cantorian nature. The mathematics used here on the other hand is the remarkably simple and insightful golden mean probability distribution known from a famous paradox known in social sciences as the voter paradox. 展开更多
关键词 dark Energy the VOTER PARADOX Golden Mean Distribution Looped light the Triple-Slit Experiment Cantorian-Fractal SPACETIME
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Light Speed Expansion and Rotation of a Very Dark Machian Universe Having Internal Acceleration
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作者 U. V. S Seshavatharam S. Lakshminarayana 《International Journal of Astronomy and Astrophysics》 2020年第3期247-283,共37页
We present a Machian model of Quantum Cosmology with full dark matter and light speed expansion and rotation. During galaxy formation and evolution, fraction of dark matter transforms to visible matter with a relation... We present a Machian model of Quantum Cosmology with full dark matter and light speed expansion and rotation. During galaxy formation and evolution, fraction of dark matter transforms to visible matter with a relation of the form, m_vis = constant * (m_dark)<sup>2/3</sup>. Using this relation and replacing MOND’s “critical acceleration” with “current cosmic maximum angular acceleration”, galactic flat rotation speed range of (50 to 500) km/sec can be fitted well. Estimated flat rotation speeds of DD168, Milky Way and UGC12591 are 49.96 km/sec, 199.66 km/sec and 521.75 km/sec respectively. Based on these striking coincidences, it is possible to say that, MOND’s approach is implicitly connected with cosmological estimation of 95% invisible matter. With reference to SPARC data for flat rotation speeds and current cosmic maximum angular acceleration, galactic total mass can be estimated. Considering galactic total mass, galactic visible mass and dark mass can be estimated. Proceeding further, galactic working radii, angular velocity and visible matter density can be estimated. Estimated Milky Way’s effective radius is 293 kpc. Even though, this model is free from “big bang”, “inflation”, “dark energy”, “flatness” and “red shift” issues, at 2.722 K, estimated present Hubble parameter is 66.24 km/sec/Mpc, cosmic radius is 146.3 times of the Hubble radius, angular velocity is 146.3 times lower than the Hubble parameter and cosmic age is 146.3 times of the Hubble age. With future observations and advanced telescopes, it may be possible to see far distant galaxies and very old stars far beyond the current observable cosmic radius. 展开更多
关键词 Planck Scale Machian Universe Speed of light Galactic dark Matter Galactic Visible Mass Galactic Visible Mass Density Cosmic Anisotropy Galactic Internal Acceleration Cosmic Graviton Wavelength
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The study of fluorescence characteristics and biochemical composition of a marine diatom Thalassiosira pseudonana 3H in light and dark cyclesI. The effects of nutrients
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作者 Zhu Mingyuan, Yang Xiaolong and J. J. Cullen 1. First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China2. Bigelow Laboratory for Ocean Sciences, U. S. A. 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第4期593-602,共10页
The effects of nutrients on the fluorescence characteristics and biochemical composition of marine diatom Thalassiosira pseudonana 3H in light and dark cycles were investigated with continuous culture. The results sho... The effects of nutrients on the fluorescence characteristics and biochemical composition of marine diatom Thalassiosira pseudonana 3H in light and dark cycles were investigated with continuous culture. The results show that with the increase of nutrient deficiency, the ratio of enhanced fluorescence to fluorescence (Fd/F), cellular chloropyll-a and protein content of the algae decline, but the fluorescence yield (F/Chl) , DCMU enhanced fluorescence yield (Fd/Chl) , cellular carbohydrate content, carbohydrate/Chl, protein/Chl, carbohydrate/protein increase. The changing amplitude of each parameter is different at different nutrition status, sampling time and different light intensity. 展开更多
关键词 The study of fluorescence characteristics and biochemical composition of a marine diatom Thalassiosira pseudonana 3H in light and dark cyclesI The effects of nutrients
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Collective behaviors of suprachiasm nucleus neurons under different light–dark cycles
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作者 顾长贵 张新华 刘宗华 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期98-106,共9页
The principal circadian clock in the suprachiasm nucleus (SCN) regulates the circadian rhythm of physiological and behavioral activities of mammals. Except for the normal function of the circadian rhythm, the ensemb... The principal circadian clock in the suprachiasm nucleus (SCN) regulates the circadian rhythm of physiological and behavioral activities of mammals. Except for the normal function of the circadian rhythm, the ensemble of SCN neurons may show two collective behaviors, i.e., a free running period in the absence of a light-dark cycle and an entrainment ability to an external T cycle. Experiments show that both the free running periods and the entrainment ranges may vary from one species to another and can be seriously influenced by the coupling among the SCN neurons. We here review the recent progress on how the heterogeneous couplings influence these two collective behaviors. We will show that in the case of homogeneous coupling, the free running period increases monotonically while the entrainment range decreases monotonically with the increase of the coupling strength. While in the case of heterogenous coupling, the dispersion of the coupling strength plays a crucial role. It has been found that the free running period decreases with the increase of the dispersion while the entrainment ability is enhanced by the dispersion. These findings provide new insights into the mechanism of the circadian clock in the SCN. 展开更多
关键词 suprachiasm nucleus light--dark cycle free running period entrainment range
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From Darkness to the Light──The 50th Anniversary of Tibet's Peaceful Liberation
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《China Today》 2001年第5期6-7,共2页
关键词 From darkness to the light The 50th Anniversary of Tibet’s Peaceful Liberation
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基于空间自适应剖分的Lightcuts多光源聚类算法
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作者 袁昱纬 刘传辉 +2 位作者 全吉成 王宏伟 吴晨 《海军航空工程学院学报》 2017年第2期181-186,198,共7页
针对Lightcuts算法在面对大规模复杂光源时计算效率较低的问题,提出了一种基于空间自适应剖分的Lightcuts多光源聚类算法。该算法采用二叉树森林代替传统Lightcuts算法中的二叉树,并提出自适应的视景体划分方法对三维场景进行剖分,通过... 针对Lightcuts算法在面对大规模复杂光源时计算效率较低的问题,提出了一种基于空间自适应剖分的Lightcuts多光源聚类算法。该算法采用二叉树森林代替传统Lightcuts算法中的二叉树,并提出自适应的视景体划分方法对三维场景进行剖分,通过构建包含"簇-光源"对的列表,快速剔除与当前渲染点无关的光源,同时利用空间聚类的相似性减少"光源割"搜索过程中的重复计算。实验结果表明,与传统方法相比,文章提出的算法在"光源割"计算阶段能够将搜索步数平均减少30.71%~42.09%,绘制时间平均缩短28.35%~34.84%,有效地加快了Lightcuts算法的计算速度,提高了多光源三维场景的绘制效率。 展开更多
关键词 多光源 lightcuts 自适应空间剖分 二叉树森林 场景绘制
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The Commentary on A Clean, Well-lighted Place by Hemingway
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作者 毛怀周 顾英玲 《海外英语》 2011年第8X期366-367,共2页
The commentary on A Clean, well-lighted Place intends to release general introduction about Hemingway's short story, especially his writing styles through a few short conversations between the young and middle-age... The commentary on A Clean, well-lighted Place intends to release general introduction about Hemingway's short story, especially his writing styles through a few short conversations between the young and middle-aged waiters to evince the value of life in simple words by Hemingway. 展开更多
关键词 Café CONVERSATIONS dark DESPAIR light tidy Nada
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