text stringlengths 14 4.79k | source stringlengths 13 304 | tokens float64 75 1.06k ⌀ | char_length float64 106 4.79k ⌀ | article_title stringlengths 16 300 ⌀ |
|---|---|---|---|---|
The model focuses on five major concerns: (1) location suitability, (2) operational sustainability, (3) environmental sustainability, (4) socioeconomic sustainability, and (5) site capacity sustainability. This framework was developed in 2021, as such most established waste disposal sites do not take these factors into... | Wikipedia - Ecological Design | null | null | null |
Waste facilities such as dumps and incinerators are disproportionately placed in areas with low education and income levels, burdening these vulnerable populations with pollution and exposure to hazardous materials. For example, legislation in the United States, such as the Cerrell Report, has encouraged these types of... | Wikipedia - Ecological Design | null | null | null |
Life cycle engineering is an assessment methodology and practice faced with increasing demand in the architectural, construction, and design industries. The shift toward "green building" or sustainable construction has increased the need for LCE in the design, construction, operation, and demolition of buildings. Newly... | Wikipedia - Life-cycle engineering | null | null | null |
The costs LCE or of conducting life-cycle assessment (LCA) and life-cycle cost analysis (LCCA) are outweighed and justified by the benefits of such assessments, increasing the integration of LCE within sustainable construction practices. Specific demand for LCE in sustainable construction practices can be attributed to... | Wikipedia - Life-cycle engineering | null | null | null |
Green building rating systems have supported and encouraged the use of LCE and LCA as methods to improve the standards and requirements of rating systems, while also advancing industry-wide standards for integrated building sustainability considerations.Concluding paragraph of an earlier article on life cycle assessmen... | Wikipedia - Life-cycle engineering | null | null | null |
“ 1 R.Chattopadhyay: Green Tribology, Green Surface Engineering and Global Warming,2014,ASM International,OH,USA 2. R.Chattopadhyay: Surface Wear, Analysis, Treatment, and Prevention,2001,ASM International, OH, USA 3. R.Chattopadhyay: Advanced Thermally Assisted Surface Engineering Processes, 2004, Springer, NY, USA. 4... | Wikipedia - Life-cycle engineering | null | null | null |
Life cycle engineering is defined in the CIRP Encyclopedia of Production Engineering as: “the engineering activities which include the application of technological and scientific principles to manufacturing products with the goal of protecting the environment, conserving resources, encouraging economic progress, keepin... | Wikipedia - Life-cycle engineering | null | null | null |
Life defined as biologically immortal is still susceptible to causes of death besides aging, including disease and trauma, as defined above. Notable immortal species include: Bacteria – Bacteria reproduce through binary fission. A parent bacterium splits itself into two identical daughter cells which eventually then sp... | Wikipedia - Immortality of the soul | null | null | null |
A 2005 PLoS Biology paper suggests that after each division the daughter cells can be identified as the older and the younger, and the older is slightly smaller, weaker, and more likely to die than the younger. Turritopsis dohrnii, a jellyfish (phylum Cnidaria, class Hydrozoa, order Anthoathecata), after becoming a sex... | Wikipedia - Immortality of the soul | null | null | null |
Its immortal adaptation has allowed it to spread from its original habitat in the Caribbean to "all over the world". Hydra is a genus belonging to the phylum Cnidaria, the class Hydrozoa and the order Anthomedusae. They are simple fresh-water predatory animals possessing radial symmetry. | Wikipedia - Immortality of the soul | null | null | null |
Life expectancy of the Amazon river dolphin in the wild is unknown, but in captivity, the longevity of healthy individuals has been recorded at between 10 and 30 years. However, a 1986 study of the average longevity in captive animals in the United States is only 33 months. An individual named Baby at the Duisburg Zoo,... | Wikipedia - Amazon dolphin | null | null | null |
Life harnesses chemical reactions to generate energy, perform biosynthesis, and eliminate waste. Different organisms use very different metabolic approaches to meet these basic needs. While animals such as ourselves are limited to aerobic respiration, other organisms can "breathe" sulfate (SO42-), nitrate (NO3-), ferri... | Wikipedia - Geobiology | null | null | null |
Plants are photoautotrophs, in that they use the energy of light to fix carbon. Microorganisms employ oxygenic and anoxygenic photoautotrophy, as well as chemoautotrophy. Microbial communities can coordinate in syntrophic metabolisms to shift reaction kinetics in their favor. | Wikipedia - Geobiology | null | null | null |
Many organisms can perform multiple metabolisms to achieve the same end goal; these are called mixotrophs.Biotic metabolism is directly tied to the global cycling of elements and compounds on Earth. The geochemical environment fuels life, which then produces different molecules that go into the external environment. (T... | Wikipedia - Geobiology | null | null | null |
Life has made dramatic changes in the environment. Most dramatic was the Great Oxygenation Event, about 2.4 billion years ago, in which photosynthetic organisms flooded the atmosphere with oxygen. Living organisms also catalyze reactions, creating minerals such as aragonite that are not in equilibrium with their surrou... | Wikipedia - Mineral evolution | null | null | null |
Life has traditionally been seen as driven by energy from the sun, but deep-sea organisms have no access to sunlight, so biological communities around hydrothermal vents must depend on nutrients found in the dusty chemical deposits and hydrothermal fluids in which they live. Previously, Benthic oceanographers assumed t... | Wikipedia - Deep sea vent | null | null | null |
Some hydrothermal vent organisms do consume this "rain", but with only such a system, life forms would be sparse. Compared to the surrounding sea floor, however, hydrothermal vent zones have a density of organisms 10,000 to 100,000 times greater. These organisms include yeti crabs, which have long hairy arms that they ... | Wikipedia - Deep sea vent | null | null | null |
Hydrothermal vent communities are able to sustain such vast amounts of life because vent organisms depend on chemosynthetic bacteria for food. The water from the hydrothermal vent is rich in dissolved minerals and supports a large population of chemoautotrophic bacteria. These bacteria use sulfur compounds, particularl... | Wikipedia - Deep sea vent | null | null | null |
Life requires a loss of entropy, or disorder, when molecules organize themselves into living matter. The emergence of life and increased complexity does not contradict the second law of thermodynamics, which states that overall entropy never decreases, since a living organism creates order in some places (e.g. its livi... | Wikipedia - Origin of Life | null | null | null |
This has been confirmed by experiments and simulations. Unfavorable reactions can be driven by highly favorable ones, as in the case of iron-sulfur chemistry. For example, this was probably important for carbon fixation. Carbon fixation by reaction of CO2 with H2S via iron-sulfur chemistry is favorable, and occurs at n... | Wikipedia - Origin of Life | null | null | null |
Life science organizations have outlined the dangers climate change pose to wildlife. American Association of Wildlife Veterinarians American Institute of Biological Sciences. In October 2009, the leaders of 18 US scientific societies and organizations sent an open letter to the United States Senate reaffirming the sci... | Wikipedia - Scientific consensus on climate change | null | null | null |
The letter goes on to warn of predicted impacts on the United States such as sea level rise and increases in extreme weather events, water scarcity, heat waves, wildfires, and the disturbance of biological systems. It then advocates for a dramatic reduction in emissions of greenhouse gases. American Society for Microbi... | Wikipedia - Scientific consensus on climate change | null | null | null |
Life science, also known as biology, is the natural science that studies life such as microorganisms, plants, and animals including human beings, – including their physical structure, chemical processes, molecular interactions, physiological mechanisms, development, and evolution. Despite the complexity of the science,... | Wikipedia - Scientific discipline | null | null | null |
Life sciences is flourishing with ontologies that biologists use to make sense of their experiments. For inferring correct conclusions from experiments, ontologies have to be structured optimally against the knowledge base they represent. The structure of an ontology needs to be changed continuously so that it is an ac... | Wikipedia - Ontology Engineering | null | null | null |
Based on information theory, it restructures ontologies so that the levels represent the desired specificity of the concepts. Similar information theoretic approaches have also been used for optimal partition of Gene Ontology. | Wikipedia - Ontology Engineering | null | null | null |
Given the mathematical nature of such engineering algorithms, these optimizations can be automated to produce a principled and scalable architecture to restructure ontologies such as GO. Open Biomedical Ontologies (OBO), a 2006 initiative of the U.S. National Center for Biomedical Ontology, provides a common 'foundry' ... | Wikipedia - Ontology Engineering | null | null | null |
Life span, like other phenotypes, is selected for in evolution. Traits that benefit early survival and reproduction will be selected for even if they contribute to an earlier death. Such a genetic effect is called the antagonistic pleiotropy effect when referring to a gene (pleiotropy signifying the gene has a double f... | Wikipedia - Aging process | null | null | null |
LifeAct-TagGFP2 being the most widely used fluorescent variant compared to other LifeAct constructs is composed of the first 17 amino acid from the Saccharomyces cerevisiae Abp140, an actin-binding protein. The Abp140 is highly conserved among Saccharomyces cerevisiae and other closely related organisms. The 17 amino a... | Wikipedia - LifeAct Dye | null | null | null |
Previous experiments involving the analysis of cell mechanics had depended on fluorescently labeled phalloidin and actin GFP fusion proteins obtained from utrophin in Xenopus laevis and ABP120 in Dictyostelium discoideum. However, due to their large protein size, markers such as phalloidin and GFP fusion proteins are l... | Wikipedia - LifeAct Dye | null | null | null |
Lifecycle Modeling Language (LML), is an open-standard modeling language designed for systems engineering that supports the full lifecycle: conceptual, utilization, support and retirement stages. | Wikipedia - Interactive system | null | null | null |
Lifestreams also represent a source of information about people's intents that can be mined. A common bridge between all concepts of lifestreaming is the gathering of statistical data. With computerized support that simplifies one's daily choices and activities, it can be much easier to identify certain common traits i... | Wikipedia - Lifestreaming | null | null | null |
Lifshitz, E. M. & Pitaevskii, L. P. (1981). Physical kinetics. | Wikipedia - List of textbooks in thermodynamics and statistical mechanics | null | null | null |
Vol. 10 of the Course of Theoretical Physics (3rd Ed). Translated by J.B. | Wikipedia - List of textbooks in thermodynamics and statistical mechanics | null | null | null |
Sykes and R.N. Franklin (1981) London: Pergamon ISBN 0-08-026480-8, ISBN 0-7506-2635-6 Zubarev, D. N. (1974). | Wikipedia - List of textbooks in thermodynamics and statistical mechanics | null | null | null |
Nonequilibrium Statistical Thermodynamics. New York: Consultants Bureau. ISBN 978-0-306-10895-2. | Wikipedia - List of textbooks in thermodynamics and statistical mechanics | null | null | null |
Zubarev, D. N.; Morozov V.; Ropke G. (1996). Statistical Mechanics of Nonequilibrium Processes: Basic Concepts, Kinetic Theory. | Wikipedia - List of textbooks in thermodynamics and statistical mechanics | null | null | null |
John Wiley & Sons. ISBN 3-05-501708-0. Zubarev, D. N.; Morozov V.; Ropke G. | Wikipedia - List of textbooks in thermodynamics and statistical mechanics | null | null | null |
(1997). Statistical Mechanics of Nonequilibrium Processes: Relaxation and Hydrodynamic Processes. John Wiley & Sons. ISBN 3-527-40084-2. | Wikipedia - List of textbooks in thermodynamics and statistical mechanics | null | null | null |
Lifshitz, Evgeny M.; Pitaevskii, Lev P. (1980). Statistical Physics, Part 2: Theory of the Condensed State. Vol. | Wikipedia - Course of Theoretical Physics | null | null | null |
9 (1st ed.). Butterworth-Heinemann. ISBN 978-0-7506-2636-1.Volume 9 builds on the original statistical physics book, with more applications to condensed matter theory. | Wikipedia - Course of Theoretical Physics | null | null | null |
Lifshitz, Evgeny M.; Pitaevskii, Lev P. (1981). Physical Kinetics. Vol. | Wikipedia - Course of Theoretical Physics | null | null | null |
10 (1st ed.). Pergamon Press. ISBN 978-0-7506-2635-4.Volume 10 presents various applications of kinetic theory to condensed matter theory, and to metals, insulators, and phase transitions. | Wikipedia - Course of Theoretical Physics | null | null | null |
LigDs form a subfamily of the DNA ligases. These all have a LigDom/ligase domain, but many bacterial LigDs also have separate polymerase domains/PolDoms and nuclease domains/NucDoms. In P. aeruginosa's case the nuclease domains are N-terminus, and the polymerase domains are C-terminus, extensions of the single central ... | Wikipedia - Pseudomonas aeruginosa | null | null | null |
Ligands are ordered alphabetically by name and precede the central atom name. The number of ligands coordinating is indicated by the prefixes di-, tri-, tetra- penta- etc. for simple ligands or bis-, tris-, tetrakis-, etc. for complex ligands. For example: Cl2 pentaamminechloridocobalt(3+) chloride where ammine (NH3)pr... | Wikipedia - IUPAC nomenclature of inorganic chemistry 2005 | null | null | null |
The central atom name(s) come after the ligands. Where there is more than one central atom it is preceded by di- tri-, tetra- etc. Os3(CO)12, dodecacarbonyltriosmiumWhere there are different central atoms they are sequenced using the electronegativity list. nonacarbonylrheniumcobalt | Wikipedia - IUPAC nomenclature of inorganic chemistry 2005 | null | null | null |
Ligands may bridge two or more centres. The prefix μ is used to specify a bridging ligand in both the formula and the name. For example the dimeric form of aluminium trichloride: Al2Cl4(μ-Cl)2di-μ-chlorido-tetrachlorido-1κ2Cl,2κ2Cl-dialuminiumThis example illustrates the ordering of bridging and non bridging ligands of... | Wikipedia - IUPAC nomenclature of inorganic chemistry 2005 | null | null | null |
Ligands targeting the mAChR that are currently approved for clinical use include non-selective antagonists for the treatment of Parkinson's disease, atropine (to dilate the pupil), scopolamine (used to prevent motion sickness), and ipratropium (used in the treatment of COPD). | Wikipedia - Muscarinic receptor | null | null | null |
Ligation may also serve as a DNA analysis method. Some techniques employ rolling circle amplification. The most notable of these is described by Smolina et al., 2007 & Smolina et al., 2008 using fluorescence in situ hybridization and peptide nucleic acids. They developed and employed this technique for analyses of bact... | Wikipedia - Blunt-end ligation | null | null | null |
Light and melatoninMore recently, light therapy and melatonin administration have been explored by Alfred J. Lewy (OHSU), Josephine Arendt (University of Surrey, UK) and other researchers as a means to reset animal and human circadian rhythms. Additionally, the presence of low-level light at night accelerates circadian... | Wikipedia - Biological rhythms | null | null | null |
The location of this clock has been disputed. Working with mice, however, Fuller et al. concluded that the food-entrainable clock seems to be located in the dorsomedial hypothalamus. During restricted feeding, it takes over control of such functions as activity timing, increasing the chances of the animal successfully ... | Wikipedia - Biological rhythms | null | null | null |
Diurnal patterns on the InternetIn 2018 a study published in PLoS ONE showed how 73 psychometric indicators measured on Twitter Content follow a diurnal pattern. A followup study appeared on Chronobiology International in 2021 showed that these patterns were not disrupted by the 2020 UK lockdown. Modulators of circadia... | Wikipedia - Biological rhythms | null | null | null |
Light can be used to transmit data and analog signals. For example, lighting white LEDs can be used in systems assisting people to navigate in closed spaces while searching necessary rooms or objects.Assistive listening devices in many theaters and similar spaces use arrays of infrared LEDs to send sound to listeners' ... | Wikipedia - White LED | null | null | null |
Because LEDs can cycle on and off millions of times per second, very high data bandwidth can be achieved. For that reason, Visible Light Communication (VLC) has been proposed as an alternative to the increasingly competitive radio bandwidth. By operating in the visible part of the electromagnetic spectrum, data can be ... | Wikipedia - White LED | null | null | null |
The main characteristic of VLC, lies on the incapacity of light to surpass physical opaque barriers. This characteristic can be considered a weak point of VLC, due to the susceptibility of interference from physical objects, but is also one of its many strengths: unlike radio waves, light waves are confined in the encl... | Wikipedia - White LED | null | null | null |
Additionally, once the VLC lamps are able to perform lighting at the same time as data transmission, it can simply occupy the installation of traditional single-function lamps. Other applications for VLC involve communication between appliances of a smart home or office. With increasing IoT-capable devices, connectivit... | Wikipedia - White LED | null | null | null |
Light comes in particles and the energy of a light-particle (the photon) is the frequency of the light times Planck's constant. A fundamental property of any photographic method is how it collects the light on its photographic plate or electronic detector. | Wikipedia - Science of photography | null | null | null |
Light conditions may be considered gloomy when the level of light in an environment is too low for the proper function of cone cells, and colour vision is lost. In a study by Rothwell and Campbell, light levels described as "gloomy" fell between 28 and 3.6 cd/m−2.Low light and lack of color of this sort may be associat... | Wikipedia - Gloom | null | null | null |
Also, some studies have found weaker electrical activity in the retinas of depressed people, which gave the individuals studied poor visual contrast, meaning that they saw the world in grayer hues. The naturally weak daylight during winter at extreme latitudes can cause seasonal affective disorder (SAD), although a per... | Wikipedia - Gloom | null | null | null |
Light enters the camera through an aperture, an opening adjusted by overlapping plates called the aperture ring. Typically located in the lens, this opening can be widened or narrowed to alter the amount of light that strikes the film or sensor. The size of the aperture can be set manually, by rotating the lens or adju... | Wikipedia - Still camera | null | null | null |
The smaller the f-stop, the more light is allowed to enter the lens, increasing the exposure. Typically, f-stops range from f/1.4 to f/32 in standard increments: 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, and 32. | Wikipedia - Still camera | null | null | null |
The light entering the camera is halved with each increasing increment.The wider opening at lower f-stops narrows the range of focus so the background is blurry while the foreground is in focus. This depth of field increases as the aperture closes. A narrow aperture results in a high depth of field, meaning that object... | Wikipedia - Still camera | null | null | null |
Light harvesting in photosynthesis employs both classical and quantum mechanical processes with an energy efficiency of almost 100 percent. For light to produce energy in classical processes, photons must reach reaction sites before their energy dissipates in less than one nanosecond. In photosynthetic processes, this ... | Wikipedia - FMO complex | null | null | null |
Because energy can exist in a superposition of states, it can travel all routes within a material at the same time. When a photon finds the correct destination, the superposition collapses, making the energy available. However, no purely quantum process can be wholly responsible, because some quantum processes slow dow... | Wikipedia - FMO complex | null | null | null |
Anderson localization prevents the spread of quantum states in random media. Because the state acts like a wave, it is vulnerable to disruptive interference effects. Another issue is the quantum zeno effect, in which an unstable state never changes if it is continuously measured/watched, because watching constantly nud... | Wikipedia - FMO complex | null | null | null |
The classical interaction with the environment changes the wave-like nature of the quantum state just enough to prevent Anderson localisation, while the quantum zeno effect extends the quantum state's lifetime, allowing it to reach the reaction centre. The proposed long lifetime of quantum coherence in the FMO influenc... | Wikipedia - FMO complex | null | null | null |
Light in thermal equilibrium has a black-body spectrum with an energy density proportional to the fourth power of the temperature (hence the Stefan–Boltzmann law). The wavelength of maximum emission from a blackbody is inversely proportional to its temperature. That is, the frequency, and the energy, of the greatest po... | Wikipedia - Pulsational pair-instability supernova | null | null | null |
Light is absorbed and reflected in water. Visible white light is made up of a spectrum of colors from the rainbow, ranging from red to violet. As the light travels through the water, the waves of light from the red end of the spectrum dissipate (i.e. are absorbed), while those from the blue end, become more prominent.U... | Wikipedia - Blue iceberg | null | null | null |
As the diver swims deeper under water, the colors begin to disappear, starting with red. At an approximate depth of 30 feet (9.1 m), red is no longer visible to the naked eye. At 75 feet (23 m), yellow looks greenish-blue, because the water has absorbed the yellow light. Finally, all that remains visible to the naked e... | Wikipedia - Blue iceberg | null | null | null |
Light is the food of plants, i.e. the form of energy that plants use to build themselves and reproduce. The organs harvesting light in plants are leaves and the process through which light is converted into biomass is photosynthesis. The response of photosynthesis to light is called light response curve of net photosyn... | Wikipedia - Ecophysiology | null | null | null |
Three quantities of the light response curve are particularly useful in characterising a plant's response to light intensities. The inclined asymptote has a positive slope representing the efficiency of light use, and is called quantum efficiency; the x-intercept is the light intensity at which biochemical assimilation... | Wikipedia - Ecophysiology | null | null | null |
As with most abiotic factors, light intensity (irradiance) can be both suboptimal and excessive. Suboptimal light (shade) typically occurs at the base of a plant canopy or in an understory environment. Shade tolerant plants have a range of adaptations to help them survive the altered quantity and quality of light typic... | Wikipedia - Ecophysiology | null | null | null |
Excess light occurs at the top of canopies and on open ground when cloud cover is low and the sun's zenith angle is low, typically this occurs in the tropics and at high altitudes. Excess light incident on a leaf can result in photoinhibition and photodestruction. Plants adapted to high light environments have a range ... | Wikipedia - Ecophysiology | null | null | null |
Light may pass through anisotropic inhomogeneous media at different rates depending on the direction and starting position of a light ray. The boundary of the set of points to which light can travel from a given point q after a time t is known as the wave front after time t, denoted here by Φq(t). It consists of precis... | Wikipedia - Envelope (mathematics) | null | null | null |
Light particles, or photons, travel at the speed of c, the constant that is conventionally known as the speed of light. This statement is not a tautology, since many modern formulations of relativity do not start with constant speed of light as a postulate. Photons therefore propagate along a lightlike world line and, ... | Wikipedia - Spacetime geometry | null | null | null |
Rearranging, E / c = p {\displaystyle E/c=p} , and since for photons, the space and time components are equal, E/c must therefore be equated with the time component of the spacetime momentum vector. Photons travel at the speed of light, yet have finite momentum and energy. For this to be so, the mass term in γmc must b... | Wikipedia - Spacetime geometry | null | null | null |
Infinity times zero is an ill-defined quantity, but E/c is well-defined. By this analysis, if the energy of a photon equals E in the rest frame, it equals E ′ = ( 1 − β ) γ E {\displaystyle E^{\prime }=(1-\beta )\gamma E} in a moving frame. This result can be derived by inspection of Fig. 3-9 or by application of the L... | Wikipedia - Spacetime geometry | null | null | null |
Light pollution impacts migration in some species of fish. For example, juvenile chinook salmon are attracted to and slowed down by artificial light. It is possible that artificial light draws them closer to the shoreline, where they face a greater risk of predation from birds and mammals. Artificial lighting also attr... | Wikipedia - Ecological light pollution | null | null | null |
Light production in fireflies is due to the chemical process of bioluminescence. This occurs in specialized light-emitting organs, usually on a female firefly's lower abdomen. The enzyme luciferase acts on luciferin, in the presence of magnesium ions, ATP, and oxygen to produce light. Oxygen is supplied via an abdomina... | Wikipedia - Firefly | null | null | null |
Gene coding for these substances has been inserted into many different organisms. Firefly luciferase is used in forensics, and the enzyme has medical uses – in particular, for detecting the presence of ATP or magnesium. Fireflies produce a "cold light", with no infrared or ultraviolet frequencies. | Wikipedia - Firefly | null | null | null |
The light may be yellow, green, or pale red, with wavelengths from 510 to 670 nanometers. Some species such as the dimly glowing "blue ghost" of the Eastern US may seem to emit blueish-white light from a distance and in low light conditions, but their glow is bright green when observed up close. Their perceived blue ti... | Wikipedia - Firefly | null | null | null |
Early larval bioluminescence was adopted in the phylogeny of adult fireflies, and was repeatedly gained and lost before becoming fixed and retained as a mechanism of sexual communication in many species. Adult lampyrids have a variety of ways to communicate with mates in courtships: steady glows, flashing, and the use ... | Wikipedia - Firefly | null | null | null |
Some species, especially lightning bugs of the genera Photinus, Photuris, and Pyractomena, are distinguished by the unique courtship flash patterns emitted by flying males in search of females. In general, females of the genus Photinus do not fly, but do give a flash response to males of their own species. Signals, whe... | Wikipedia - Firefly | null | null | null |
Flash signaling characteristics include differences in duration, timing, color, number and rate of repetitions, height of flight, and direction of flight (e.g. climbing or diving) and vary interspecifically and geographically. When flash signals are not sufficiently distinguished between species in a population, sexual... | Wikipedia - Firefly | null | null | null |
Tropical fireflies routinely synchronise their flashes among large groups, particularly in Southeast Asia. At night along river banks in the Malaysian jungles, fireflies synchronize their light emissions precisely. Current hypotheses about the causes of this behavior involve diet, social interaction, and altitude. | Wikipedia - Firefly | null | null | null |
In the Philippines, thousands of fireflies can be seen all year-round in the town of Donsol. In the United States, one of the most famous sightings of fireflies blinking in unison occurs annually near Elkmont, Tennessee, in the Great Smoky Mountains during the first weeks of June. Congaree National Park in South Caroli... | Wikipedia - Firefly | null | null | null |
This provides the females with a supply of the toxic defensive lucibufagin chemicals.Many fireflies do not produce light. Usually these species are diurnal, or day-flying, such as those in the genus Ellychnia. A few diurnal fireflies that inhabit primarily shadowy places, such as beneath tall plants or trees, are lumin... | Wikipedia - Firefly | null | null | null |
One such genus is Lucidota. Non-bioluminescent fireflies use pheromones to signal mates. | Wikipedia - Firefly | null | null | null |
This is supported by the fact that some basal groups do not show bioluminescence and use chemical signaling, instead. Phosphaenus hemipterus has photic organs, yet is a diurnal firefly and displays large antennae and small eyes. These traits strongly suggest pheromones are used for sexual selection, while photic organs... | Wikipedia - Firefly | null | null | null |
Light resets the biological clock in accordance with the phase response curve (PRC). Depending on the timing, light can advance or delay the circadian rhythm. Both the PRC and the required illuminance vary from species to species, and lower light levels are required to reset the clocks in nocturnal rodents than in huma... | Wikipedia - Day length dependent | null | null | null |
Light stress can be tolerated by dissipating excess energy as heat through the xanthophyll cycle. Violaxanthin and zeaxanthin are carotenoid molecules within the chloroplasts called xanthophylls. Under normal conditions, violaxanthin channels light to photosynthesis. However, high light levels promote the reversible co... | Wikipedia - Drought-tolerant plant | null | null | null |
These two molecules are photo-protective molecules. Under high light, it is unfavourable to channel extra light into photosynthesis because excessive light may cause damage to the plant proteins. Zeaxanthin dissociates light-channelling from the photosynthesis reaction - light energy in the form of photons will not be ... | Wikipedia - Drought-tolerant plant | null | null | null |
Light that is governed by sub-Poisson statistics cannot be described by classical electromagnetic theory and is defined by Δ n 2 < ⟨ n ⟩ {\displaystyle {\Delta n}^{2}<\langle n\rangle } . The advent of ultrafast photodetectors has made it possible to measure the sub-Poissonian nature of light. An example of light exhib... | Wikipedia - Photon Statistics | null | null | null |
A technique used to measure the sub-Poissonian structure of light is a homodyne intensity correlation scheme. In this scheme a local oscillator and signal field are superimposed via a beam splitter. | Wikipedia - Photon Statistics | null | null | null |
The superimposed light is then split by another beam splitter and each signal is recorded by individual photodetectors connected to correlator from which the intensity correlation can be measured. Evidence of the sub-Poissonian nature of light is shown by obtaining a negative intensity correlation as was shown in. == R... | Wikipedia - Photon Statistics | null | null | null |
Light that is governed by super-Poissonian statistics exhibits a statistical distribution with variance Δ n 2 > ⟨ n ⟩ {\displaystyle {\Delta n}^{2}>\langle n\rangle } . An example of light that exhibits super-Poissonian statistics is thermal light. The intensity of thermal light fluctuates randomly and the fluctuations... | Wikipedia - Photon Statistics | null | null | null |
Thermal light can be modeled as a collection of N {\displaystyle N} harmonic oscillators. Suppose the j {\displaystyle j} -th oscillator emits an electromagnetic field E j ( t ) = E 0 e − i ω t e i ϕ j ( t ) {\displaystyle E_{j}(t)=E_{0}e^{-i\omega t}e^{i\phi _{j}(t)}} with phase ϕ j ( t ) {\displaystyle \phi _{j}(t)} ... | Wikipedia - Photon Statistics | null | null | null |
Because the oscillators are uncorrelated, the phase of the superposed field will be random. Therefore, the complex amplitude β ( t ) {\displaystyle \beta (t)} is a stochastic variable. It represents the sum of the uncorrelated phases of the oscillators which models the intensity fluctuations in thermal light. | Wikipedia - Photon Statistics | null | null | null |
On the complex plane, it represents a two dimensional random walker with N {\displaystyle N} representing the steps taken. For large N {\displaystyle N} a random walker has a Gaussian probability distribution. Thus, the joint probability distribution for the real and imaginary parts of the complex random variable β ( t... | Wikipedia - Photon Statistics | null | null | null |
e − ϵ I P ( I ) d I {\displaystyle P(n)=\int _{0}^{\infty }{\frac {{\left(\epsilon I\right)}^{n}}{n! }}e^{-\epsilon I}P(I)dI} The factor ϵ = η h ν {\displaystyle \epsilon ={\frac {\eta }{h\nu }}} where η {\displaystyle \eta } is the quantum efficiency describes the efficiency of the photon counter. A perfect detector w... | Wikipedia - Photon Statistics | null | null | null |
I {\displaystyle I} is the intensity incident on an area A of the photodetector and is given by I = ∬ A ∫ t t + τ I ( x , y , t ′ ) d t ′ d x d y {\displaystyle I=\iint \limits _{A}\int _{t}^{t+\tau }\,I(x,y,t')dt'\,dx\,dy} On substituting the intensity probability distribution of thermal light for P(I), Mandel's formu... | Wikipedia - Photon Statistics | null | null | null |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.