Gamma Rays: Penetrating, high-energy electromagnetic radiation emitted from atomic nuclei during NUCLEAR DECAY. The range of wavelengths of emitted radiation is between 0.1 - 100 pm which overlaps the shorter, more energetic hard X-RAYS wavelengths. The distinction between gamma rays and X-rays is based on their radiation source.Positron-Emission Tomography: An imaging technique using compounds labelled with short-lived positron-emitting radionuclides (such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18) to measure cell metabolism. It has been useful in study of soft tissues such as CANCER; CARDIOVASCULAR SYSTEM; and brain. SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY is closely related to positron emission tomography, but uses isotopes with longer half-lives and resolution is lower.Otoacoustic Emissions, Spontaneous: Self-generated faint acoustic signals from the inner ear (COCHLEA) without external stimulation. These faint signals can be recorded in the EAR CANAL and are indications of active OUTER AUDITORY HAIR CELLS. Spontaneous otoacoustic emissions are found in all classes of land vertebrates.Tomography, Emission-Computed: Tomography using radioactive emissions from injected RADIONUCLIDES and computer ALGORITHMS to reconstruct an image.Vehicle Emissions: Gases, fumes, vapors, and odors escaping from the cylinders of a gasoline or diesel internal-combustion engine. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Random House Unabridged Dictionary, 2d ed)Fluorodeoxyglucose F18: The compound is given by intravenous injection to do POSITRON-EMISSION TOMOGRAPHY for the assessment of cerebral and myocardial glucose metabolism in various physiological or pathological states including stroke and myocardial ischemia. It is also employed for the detection of malignant tumors including those of the brain, liver, and thyroid gland. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1162)Radiopharmaceuticals: Compounds that are used in medicine as sources of radiation for radiotherapy and for diagnostic purposes. They have numerous uses in research and industry. (Martindale, The Extra Pharmacopoeia, 30th ed, p1161)Elasmobranchii: A subclass of cartilaginous fish comprising the SHARKS; rays; skates (SKATES (FISH);), and sawfish. Elasmobranchs are typically predaceous, relying more on smell (the olfactory capsules are relatively large) than sight (the eyes are relatively small) for obtaining their food.Skates (Fish): The common name for all members of the Rajidae family. Skates and rays are members of the same order (Rajiformes). Skates have weak electric organs.Tomography, Emission-Computed, Single-Photon: A method of computed tomography that uses radionuclides which emit a single photon of a given energy. The camera is rotated 180 or 360 degrees around the patient to capture images at multiple positions along the arc. The computer is then used to reconstruct the transaxial, sagittal, and coronal images from the 3-dimensional distribution of radionuclides in the organ. The advantages of SPECT are that it can be used to observe biochemical and physiological processes as well as size and volume of the organ. The disadvantage is that, unlike positron-emission tomography where the positron-electron annihilation results in the emission of 2 photons at 180 degrees from each other, SPECT requires physical collimation to line up the photons, which results in the loss of many available photons and hence degrades the image.Greenhouse Effect: The effect of GLOBAL WARMING and the resulting increase in world temperatures. The predicted health effects of such long-term climatic change include increased incidence of respiratory, water-borne, and vector-borne diseases.Fluorine Radioisotopes: Unstable isotopes of fluorine that decay or disintegrate emitting radiation. F atoms with atomic weights 17, 18, and 20-22 are radioactive fluorine isotopes.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Animal Fins: Membranous appendage of fish and other aquatic organisms used for locomotion or balance.Cathode Ray Tube: A vacuum tube equipped with an electron emitting CATHODE and a fluorescent screen which emits visible light when excited by the cathode ray. Cathode ray tubes are used as imaging devises for TELEVISIONS; COMPUTER TERMINALS; TEXT TELECOMMUNICATION DEVICES; oscilloscopes; and other DATA DISPLAY devices.Carbon Footprint: A measure of the total greenhouse gas emissions produced by an individual, organization, event, or product. It is measured in units of equivalent kilograms of CARBON DIOXIDE generated in a given time frame.Air Pollutants: Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or material. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.Methane: The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)Cosmic Radiation: High-energy radiation or particles from extraterrestrial space that strike the earth, its atmosphere, or spacecraft and may create secondary radiation as a result of collisions with the atmosphere or spacecraft.Multimodal Imaging: The use of combination of imaging techniques or platforms (e.g., MRI SCAN and PET SCAN) encompassing aspects of anatomical, functional, or molecular imaging methods.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Ultraviolet Rays: That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.Atmosphere: The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)Volatilization: A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.Pentanes: Five-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Carbon Radioisotopes: Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.Spectrometry, X-Ray Emission: The spectrometric analysis of fluorescent X-RAYS, i.e. X-rays emitted after bombarding matter with high energy particles such as PROTONS; ELECTRONS; or higher energy X-rays. Identification of ELEMENTS by this technique is based on the specific type of X-rays that are emitted which are characteristic of the specific elements in the material being analyzed. The characteristic X-rays are distinguished and/or quantified by either wavelength dispersive or energy dispersive methods.Environmental Monitoring: The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.Gasoline: Volative flammable fuel (liquid hydrocarbons) derived from crude petroleum by processes such as distillation reforming, polymerization, etc.Fossil Fuels: Any combustible hydrocarbon deposit formed from the remains of prehistoric organisms. Examples are petroleum, coal, and natural gas.Fluorescent Dyes: Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.Fluorescence: The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Power Plants: Units that convert some other form of energy into electrical energy.Volatile Organic Compounds: Organic compounds that have a relatively high VAPOR PRESSURE at room temperature.Infrared Rays: That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.Coal: A natural fuel formed by partial decomposition of vegetable matter under certain environmental conditions.Wood: A product of hard secondary xylem composed of CELLULOSE, hemicellulose, and LIGNANS, that is under the bark of trees and shrubs. It is used in construction and as a source of CHARCOAL and many other products.Denitrification: Nitrate reduction process generally mediated by anaerobic bacteria by which nitrogen available to plants is converted to a gaseous form and lost from the soil or water column. It is a part of the nitrogen cycle.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Luminescence: Emission of LIGHT when ELECTRONS return to the electronic ground state from an excited state and lose the energy as PHOTONS. It is sometimes called cool light in contrast to INCANDESCENCE. LUMINESCENT MEASUREMENTS take advantage of this type of light emitted from LUMINESCENT AGENTS.Nitrous Oxide: Nitrogen oxide (N2O). A colorless, odorless gas that is used as an anesthetic and analgesic. High concentrations cause a narcotic effect and may replace oxygen, causing death by asphyxia. It is also used as a food aerosol in the preparation of whipping cream.Cerebrovascular Circulation: The circulation of blood through the BLOOD VESSELS of the BRAIN.Luminescent Measurements: Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.Manure: Accumulations of solid or liquid animal excreta usually from stables and barnyards with or without litter material. Its chief application is as a fertilizer. (From Webster's 3d ed)Image Processing, Computer-Assisted: A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.X-Rays: Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.Organotechnetium Compounds: Organic compounds that contain technetium as an integral part of the molecule. These compounds are often used as radionuclide imaging agents.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Air Pollution: The presence of contaminants or pollutant substances in the air (AIR POLLUTANTS) that interfere with human health or welfare, or produce other harmful environmental effects. The substances may include GASES; PARTICULATE MATTER; or volatile ORGANIC CHEMICALS.Pseudotsuga: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are coniferous evergreen trees with long, flat, spirally arranged needles that grow directly from the branch.Sensilla: Collective name for a group of external MECHANORECEPTORS and chemoreceptors manifesting as sensory structures in ARTHROPODS. They include cuticular projections (setae, hairs, bristles), pores, and slits.Radiation Dosage: The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).Cochlea: The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.Gases: The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)Energy-Generating Resources: Materials or phenomena which can provide energy directly or via conversion.Conservation of Energy Resources: Planned management, use, and preservation of energy resources.Radioisotopes: Isotopes that exhibit radioactivity and undergo radioactive decay. (From Grant & Hackh's Chemical Dictionary, 5th ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Models, Theoretical: Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.Cobalt Radioisotopes: Unstable isotopes of cobalt that decay or disintegrate emitting radiation. Co atoms with atomic weights of 54-64, except 59, are radioactive cobalt isotopes.Photons: Discrete concentrations of energy, apparently massless elementary particles, that move at the speed of light. They are the unit or quantum of electromagnetic radiation. Photons are emitted when electrons move from one energy state to another. (From Hawley's Condensed Chemical Dictionary, 11th ed)Carbon: A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.Phantoms, Imaging: Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)Nitrogen Radioisotopes: Unstable isotopes of nitrogen that decay or disintegrate emitting radiation. N atoms with atomic weights 12, 13, 16, 17, and 18 are radioactive nitrogen isotopes.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Thallium Radioisotopes: Unstable isotopes of thallium that decay or disintegrate emitting radiation. Tl atoms with atomic weights 198-202, 204, and 206-210 are thallium radioisotopes.Bermuda: A British colony in the western North Atlantic Ocean about 640 miles east southeast of Cape Hatteras, North Carolina. It comprises a group of about 300 islands of which only about 20 are inhabited. It is called also the Bermuda Islands or the Bermudas. It was named for the Spanish explorer Juan Bermudez who visited the islands in 1515. (From Webster's New Geographical Dictionary, 1988, p140 & Room, Brewer's Dictionary of Names, 1992, p61)Diagnostic Imaging: Any visual display of structural or functional patterns of organs or tissues for diagnostic evaluation. It includes measuring physiologic and metabolic responses to physical and chemical stimuli, as well as ultramicroscopy.Solar Activity: Any type of variation in the appearance of energy output of the sun. (NASA Thesaurus, 1994)Incineration: High temperature destruction of waste by burning with subsequent reduction to ashes or conversion to an inert mass.Radioactive Tracers: Radioactive substances added in minute amounts to the reacting elements or compounds in a chemical process and traced through the process by appropriate detection methods, e.g., Geiger counter. Compounds containing tracers are often said to be tagged or labeled. (Hawley's Condensed Chemical Dictionary, 12th ed)Raclopride: A substituted benzamide that has antipsychotic properties. It is a dopamine D2 receptor (see RECEPTORS, DOPAMINE D2) antagonist.Copper Radioisotopes: Unstable isotopes of copper that decay or disintegrate emitting radiation. Cu atoms with atomic weights 58-62, 64, and 66-68 are radioactive copper isotopes.Spacecraft: Devices, manned and unmanned, which are designed to be placed into an orbit about the Earth or into a trajectory to another celestial body. (NASA Thesaurus, 1988)Pinus ponderosa: A plant species of the genus PINUS that contains isocupressic acid.TailParticulate Matter: Particles of any solid substance, generally under 30 microns in size, often noted as PM30. There is special concern with PM1 which can get down to PULMONARY ALVEOLI and induce MACROPHAGE ACTIVATION and PHAGOCYTOSIS leading to FOREIGN BODY REACTION and LUNG DISEASES.Deoxyglucose: 2-Deoxy-D-arabino-hexose. An antimetabolite of glucose with antiviral activity.Technetium Tc 99m Exametazime: A gamma-emitting RADIONUCLIDE IMAGING agent used in the evaluation of regional cerebral blood flow and in non-invasive dynamic biodistribution studies and MYOCARDIAL PERFUSION IMAGING. It has also been used to label leukocytes in the investigation of INFLAMMATORY BOWEL DISEASES.Hemiterpenes: The five-carbon building blocks of TERPENES that derive from MEVALONIC ACID or deoxyxylulose phosphate.Oximes: Compounds that contain the radical R2C=N.OH derived from condensation of ALDEHYDES or KETONES with HYDROXYLAMINE. Members of this group are CHOLINESTERASE REACTIVATORS.Gas, Natural: A combustible, gaseous mixture of low-molecular weight PARAFFIN hydrocarbons, generated below the surface of the earth. It contains mostly METHANE and ETHANE with small amounts of PROPANE; BUTANES; and higher hydrocarbons, and sometimes NITROGEN; CARBON DIOXIDE; HYDROGEN SULFIDE; and HELIUM. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Global Warming: Increase in the temperature of the atmosphere near the Earth's surface and in the troposphere, which can contribute to changes in global climate patterns.Linear Energy Transfer: Rate of energy dissipation along the path of charged particles. In radiobiology and health physics, exposure is measured in kiloelectron volts per micrometer of tissue (keV/micrometer T).Technetium Tc 99m Sestamibi: A technetium imaging agent used to reveal blood-starved cardiac tissue during a heart attack.Ear Canal: The narrow passage way that conducts the sound collected by the EAR AURICLE to the TYMPANIC MEMBRANE.Dose-Response Relationship, Radiation: The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.Ammonia: A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.Soil: The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.Predictive Value of Tests: In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.Acoustic Impedance Tests: Objective tests of middle ear function based on the difficulty (impedance) or ease (admittance) of sound flow through the middle ear. These include static impedance and dynamic impedance (i.e., tympanometry and impedance tests in conjunction with intra-aural muscle reflex elicitation). This term is used also for various components of impedance and admittance (e.g., compliance, conductance, reactance, resistance, susceptance).Radiography: Examination of any part of the body for diagnostic purposes by means of X-RAYS or GAMMA RAYS, recording the image on a sensitized surface (such as photographic film).Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Fertilizers: Substances or mixtures that are added to the soil to supply nutrients or to make available nutrients already present in the soil, in order to increase plant growth and productivity.Air Pollutants, Occupational: Air pollutants found in the work area. They are usually produced by the specific nature of the occupation.Radiometry: The measurement of radiation by photography, as in x-ray film and film badge, by Geiger-Mueller tube, and by SCINTILLATION COUNTING.HydrocarbonsTissue Distribution: Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.Agriculture: The science, art or practice of cultivating soil, producing crops, and raising livestock.Myocardial Perfusion Imaging: The creation and display of functional images showing where the blood is flowing into the MYOCARDIUM by following over time the distribution of tracers injected into the blood stream.Extraterrestrial Environment: The environment outside the earth or its atmosphere. The environment may refer to a closed cabin (such as a space shuttle or space station) or to space itself, the moon, or other planets.Iodine Radioisotopes: Unstable isotopes of iodine that decay or disintegrate emitting radiation. I atoms with atomic weights 117-139, except I 127, are radioactive iodine isotopes.Perceptual Distortion: Lack of correspondence between the way a stimulus is commonly perceived and the way an individual perceives it under given conditions.Polycyclic Hydrocarbons, Aromatic: A major group of unsaturated cyclic hydrocarbons containing two or more rings. The vast number of compounds of this important group, derived chiefly from petroleum and coal tar, are rather highly reactive and chemically versatile. The name is due to the strong and not unpleasant odor characteristic of most substances of this nature. (From Hawley's Condensed Chemical Dictionary, 12th ed, p96)Ecosystem: A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Iofetamine: An amphetamine analog that is rapidly taken up by the lungs and from there redistributed primarily to the brain and liver. It is used in brain radionuclide scanning with I-123.Radiation: Emission or propagation of acoustic waves (SOUND), ELECTROMAGNETIC ENERGY waves (such as LIGHT; RADIO WAVES; GAMMA RAYS; or X-RAYS), or a stream of subatomic particles (such as ELECTRONS; NEUTRONS; PROTONS; or ALPHA PARTICLES).Molecular Imaging: The use of molecularly targeted imaging probes to localize and/or monitor biochemical and cellular processes via various imaging modalities that include RADIONUCLIDE IMAGING; ULTRASONOGRAPHY; MAGNETIC RESONANCE IMAGING; FLUORESCENCE IMAGING; and MICROSCOPY.Gallium Radioisotopes: Unstable isotopes of gallium that decay or disintegrate emitting radiation. Ga atoms with atomic weights 63-68, 70 and 72-76 are radioactive gallium isotopes.Household Articles: Various material objects and items in the home. It includes temporary or permanent machinery and appliances. It does not include furniture or interior furnishings (FURNITURE see INTERIOR DESIGN AND FURNISHINGS; INTERIOR FURNISHINGS see INTERIOR DESIGN AND FURNISHINGS).Astronomy: The science concerned with celestial bodies and the observation and interpretation of the radiation received in the vicinity of the earth from the component parts of the universe (McGraw Hill Dictionary of Scientific and Technical Terms, 5th ed)Energy Transfer: The transfer of energy of a given form among different scales of motion. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed). It includes the transfer of kinetic energy and the transfer of chemical energy. The transfer of chemical energy from one molecule to another depends on proximity of molecules so it is often used as in techniques to measure distance such as the use of FORSTER RESONANCE ENERGY TRANSFER.Quantum Dots: Nanometer sized fragments of semiconductor crystalline material which emit PHOTONS. The wavelength is based on the quantum confinement size of the dot. They can be embedded in MICROBEADS for high throughput ANALYTICAL CHEMISTRY TECHNIQUES.Tryptophan: An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.Kinetics: The rate dynamics in chemical or physical systems.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Foot Deformities, Congenital: Alterations or deviations from normal shape or size which result in a disfigurement of the foot occurring at or before birth.Optics and Photonics: A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.Relative Biological Effectiveness: The ratio of radiation dosages required to produce identical change based on a formula comparing other types of radiation with that of gamma or roentgen rays.Fluorescence Polarization: Measurement of the polarization of fluorescent light from solutions or microscopic specimens. It is used to provide information concerning molecular size, shape, and conformation, molecular anisotropy, electronic energy transfer, molecular interaction, including dye and coenzyme binding, and the antigen-antibody reaction.Environmental Exposure: The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.Electron Probe Microanalysis: Identification and measurement of ELEMENTS and their location based on the fact that X-RAYS emitted by an element excited by an electron beam have a wavelength characteristic of that element and an intensity related to its concentration. It is performed with an electron microscope fitted with an x-ray spectrometer, in scanning or transmission mode.Evoked Potentials, Auditory, Brain Stem: Electrical waves in the CEREBRAL CORTEX generated by BRAIN STEM structures in response to auditory click stimuli. These are found to be abnormal in many patients with CEREBELLOPONTINE ANGLE lesions, MULTIPLE SCLEROSIS, or other DEMYELINATING DISEASES.Heart: The hollow, muscular organ that maintains the circulation of the blood.Coronary Circulation: The circulation of blood through the CORONARY VESSELS of the HEART.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Industrial Waste: Worthless, damaged, defective, superfluous or effluent material from industrial operations.Audiometry, Pure-Tone: Measurement of hearing based on the use of pure tones of various frequencies and intensities as auditory stimuli.Confined Spaces: A space which has limited openings for entry and exit combined with unfavorable natural ventilation such as CAVES, refrigerators, deep tunnels, pipelines, sewers, silos, tanks, vats, mines, deep trenches or pits, vaults, manholes, chimneys, etc.Equipment Design: Methods of creating machines and devices.Spectrum Analysis: The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Sulfur Oxides: Inorganic oxides of sulfur.Motor Vehicles: AUTOMOBILES, trucks, buses, or similar engine-driven conveyances. (From Random House Unabridged Dictionary, 2d ed)Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography: Tomography using single-photon emitting RADIONUCLIDES to create images that are captured in times corresponding to various points in the cardiac cycle.Trees: Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.Semiconductors: Materials that have a limited and usually variable electrical conductivity. They are particularly useful for the production of solid-state electronic devices.Populus: A plant genus of the family SALICACEAE. Balm of Gilead is a common name used for P. candicans, or P. gileadensis, or P. jackii, and sometimes also used for ABIES BALSAMEA or for COMMIPHORA.Auditory Threshold: The audibility limit of discriminating sound intensity and pitch.Metatarsophalangeal Joint: The articulation between a metatarsal bone (METATARSAL BONES) and a phalanx.Reflex, Acoustic: Intra-aural contraction of tensor tympani and stapedius in response to sound.Organometallic Compounds: A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)Biofuels: Hydrocarbon-rich byproducts from the non-fossilized BIOMASS that are combusted to generate energy as opposed to fossilized hydrocarbon deposits (FOSSIL FUELS).Caenorhabditis elegans Proteins: Proteins from the nematode species CAENORHABDITIS ELEGANS. The proteins from this species are the subject of scientific interest in the area of multicellular organism MORPHOGENESIS.Sharks: A group of elongate elasmobranchs. Sharks are mostly marine fish, with certain species large and voracious.Nitrogen Oxides: Inorganic oxides that contain nitrogen.Acoustic Stimulation: Use of sound to elicit a response in the nervous system.Fireflies: The family Lampyidae, which are bioluminescent BEETLES. They contain FIREFLY LUCIFERIN and LUCIFERASES. Oxidation of firefly luciferin results in luminescence.Particle Size: Relating to the size of solids.Environmental Pollution: Contamination of the air, bodies of water, or land with substances that are harmful to human health and the environment.Inhalation Exposure: The exposure to potentially harmful chemical, physical, or biological agents by inhaling them.Luminescent Agents: Compound such as LUMINESCENT PROTEINS that cause or emit light (PHYSICAL LUMINESCENCE).Neutrons: Electrically neutral elementary particles found in all atomic nuclei except light hydrogen; the mass is equal to that of the proton and electron combined and they are unstable when isolated from the nucleus, undergoing beta decay. Slow, thermal, epithermal, and fast neutrons refer to the energy levels with which the neutrons are ejected from heavier nuclei during their decay.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Astronomical Phenomena: Aggregates of matter in outer space, such as stars, planets, comets, etc. and the properties and processes they undergo.Animal Structures: Organs and other anatomical structures of non-human vertebrate and invertebrate animals.Hearing Tests: Part of an ear examination that measures the ability of sound to reach the brain.Climate Change: Any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). It may result from natural factors such as changes in the sun's intensity, natural processes within the climate system such as changes in ocean circulation, or human activities.Perciformes: The most diversified of all fish orders and the largest vertebrate order. It includes many of the commonly known fish such as porgies, croakers, sunfishes, dolphin fish, mackerels, TUNA, etc.Technetium: The first artificially produced element and a radioactive fission product of URANIUM. Technetium has the atomic symbol Tc, atomic number 43, and atomic weight 98.91. All technetium isotopes are radioactive. Technetium 99m (m=metastable) which is the decay product of Molybdenum 99, has a half-life of about 6 hours and is used diagnostically as a radioactive imaging agent. Technetium 99 which is a decay product of technetium 99m, has a half-life of 210,000 years.Flumazenil: A potent benzodiazepine receptor antagonist. Since it reverses the sedative and other actions of benzodiazepines, it has been suggested as an antidote to benzodiazepine overdoses.Air Pollution, Indoor: The contamination of indoor air.Dihydroxyphenylalanine: A beta-hydroxylated derivative of phenylalanine. The D-form of dihydroxyphenylalanine has less physiologic activity than the L-form and is commonly used experimentally to determine whether the pharmacological effects of LEVODOPA are stereospecific.Lung Neoplasms: Tumors or cancer of the LUNG.Occupational Exposure: The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Microscopy, Fluorescence: Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.Oxygen: An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.Nitrogen Cycle: The circulation of nitrogen in nature, consisting of a cycle of biochemical reactions in which atmospheric nitrogen is compounded, dissolved in rain, and deposited in the soil, where it is assimilated and metabolized by bacteria and plants, eventually returning to the atmosphere by bacterial decomposition of organic matter.Conservation of Natural Resources: The protection, preservation, restoration, and rational use of all resources in the total environment.Pyrenes: A group of condensed ring hydrocarbons.Aniline CompoundsAir Movements: The motion of air currents.Cadmium Compounds: Inorganic compounds that contain cadmium as an integral part of the molecule.Basilar Membrane: A basement membrane in the cochlea that supports the hair cells of the ORGAN OF CORTI, consisting keratin-like fibrils. It stretches from the SPIRAL LAMINA to the basilar crest. The movement of fluid in the cochlea, induced by sound, causes displacement of the basilar membrane and subsequent stimulation of the attached hair cells which transform the mechanical signal into neural activity.Optical Processes: Behavior of LIGHT and its interactions with itself and materials.Radionuclide Imaging: The production of an image obtained by cameras that detect the radioactive emissions of an injected radionuclide as it has distributed differentially throughout tissues in the body. The image obtained from a moving detector is called a scan, while the image obtained from a stationary camera device is called a scintiphotograph.Acoustics: The branch of physics that deals with sound and sound waves. In medicine it is often applied in procedures in speech and hearing studies. With regard to the environment, it refers to the characteristics of a room, auditorium, theatre, building, etc. that determines the audibility or fidelity of sounds in it. (From Random House Unabridged Dictionary, 2d ed)Thallium: A heavy, bluish white metal, atomic number 81, atomic weight [204.382; 204.385], symbol Tl.Lasers: An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.Dipyridamole: A phosphodiesterase inhibitor that blocks uptake and metabolism of adenosine by erythrocytes and vascular endothelial cells. Dipyridamole also potentiates the antiaggregating action of prostacyclin. (From AMA Drug Evaluations Annual, 1994, p752)Luminescent Proteins: Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.Receptors, Dopamine D2: A subfamily of G-PROTEIN-COUPLED RECEPTORS that bind the neurotransmitter DOPAMINE and modulate its effects. D2-class receptor genes contain INTRONS, and the receptors inhibit ADENYLYL CYCLASES.Spectrometry, Gamma: Determination of the energy distribution of gamma rays emitted by nuclei. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Silver: Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.Radiation Effects: The effects of ionizing and nonionizing radiation upon living organisms, organs and tissues, and their constituents, and upon physiologic processes. It includes the effect of irradiation on food, drugs, and chemicals.Calibration: Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.Metatarsal Bones: The five long bones of the METATARSUS, articulating with the TARSAL BONES proximally and the PHALANGES OF TOES distally.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Cambium: A layer of living cells between the bark and hardwood that each year produces additional wood and bark cells, forming concentric growth rings.Thermoluminescent Dosimetry: The use of a device composed of thermoluminescent material for measuring exposure to IONIZING RADIATION. The thermoluminescent material emits light when heated. The amount of light emitted is proportional to the amount of ionizing radiation to which the material has been exposed.Image Enhancement: Improvement of the quality of a picture by various techniques, including computer processing, digital filtering, echocardiographic techniques, light and ultrastructural MICROSCOPY, fluorescence spectrometry and microscopy, scintigraphy, and in vitro image processing at the molecular level.Caenorhabditis elegans: A species of nematode that is widely used in biological, biochemical, and genetic studies.Plant Stems: Parts of plants that usually grow vertically upwards towards the light and support the leaves, buds, and reproductive structures. (From Concise Dictionary of Biology, 1990)Food Irradiation: Treatment of food with RADIATION.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
  • Abstract: A balanced statistical experiment was conducted to evaluate the effect of four factors on the X-ray emission analysis for calcium (Ca), silicon (Si), iron (Fe), aluminum (Al), magnesium (Mg) and sulfur (S) in portland cement. (dren.mil)
  • References Cited UNITED STATES PATENTS 3,072,822 l/l963 Holmes 315/307 X [451 Oct. 28, 1975 Primary Examiner-James B. Mullins [5 7 ABSTRACT A system for controlling the filament power applied to a rotating anode X-ray tube when used with a three phase generator. (google.com)
  • These scientific goals are feasible with a medium class mission using existing technology combined with innovative instrumental and observational capabilities by: (a) observing with fast reaction Gamma-Ray Bursts with a high spectral resolution (R ~ 500). (uva.nl)
  • b) observing and surveying extended sources (galaxy clusters, WHIM) with high sensitivity using two wide field of view X-ray telescopes (one with a high angular resolution and the other with a high spectral resolution). (uva.nl)
  • Simulations are discussed in this paper of the x-ray spectral emissions from laser-irradiated very low-density Ge-doped silica aerogel targets using a two-dimensional radiation-hydrodynamics code incorporating a modern non-LTE superconfiguration atomic model. (ebscohost.com)
  • Spectral analysis of x-ray emission created by intense laser irradiation of copper materials. (ebscohost.com)
  • Besides the emission lines formed by the characteristic radiation of the anti-cathode, these spectral plates also showed two sharp discontinuities at fixed wave-lengths which seemed independent of the tension on the X-ray tube. (iucr.org)
  • Work carried out in 2015 and 2016 made measurements of the x-ray emission spectrum of the copper Kα complex, one of the most widely used lines for diffraction work. (nist.gov)
  • We are preparing to measure the spectrum of other important X-ray lines. (nist.gov)
  • When a material is exposed to an ion beam, atomic interactions occur that give off EM radiation of wavelengths in the x-ray part of the electromagnetic spectrum specific to an element. (wikipedia.org)
  • Assuming that the supernova remnant (SNR) shell is the site of gamma-ray production, the observed spectrum can be explained either by the decay of neutral pi mesons produced through the proton-proton collisions or by electron bremsstrahlung. (diva-portal.org)
  • The gamma-ray spectrum generated in collisions of the accelerated protons with the ambient gas is also calculated and successfully fitted to the Fermi Observatory data. (aps.org)
  • The detection and the characterization of the highenergy emission component from individual gamma-ray bursts (GRBs) is one of the key science objectives of the currently operating gamma-ray satellite AGILE, launched in April 2007. (diva-portal.org)
  • The elemental analysis of hypertrophic scar tissue, skin and silicone gel sheeting using proton induced X-ray emission, Rutherford backscattering and instrumental neutron activation analysis. (surrey.ac.uk)
  • This type of target though suffers in that surfaces are irregular and proton irradiation and X-ray take-off angles are ill defined. (surrey.ac.uk)
  • To capture the impact of high-energy photons, we include all frequencies from hard X-ray to far-infrared with enough frequency resolution to discern line emission and absorption profiles. (osti.gov)
  • The copper foam at 0.1 times solid density is observed to produce 50% greater Heα line emission than copper foil, and. (ebscohost.com)
  • We measure the coronal line emission in Seyfert 2 to be weaker than in Seyfert 1 of the same bolometric luminosity suggesting obscuration by the nuclear torus. (ufrgs.br)
  • The holes were sometimes filled by an electron belonging to a neighboring atom - emitting X-ray signatures with distinct ionization potentials that would distinguish between different kinds of atoms. (redorbit.com)
  • A field emission x-ray apparatus and pulsed vacuum arc method of operation is described in which a plurality of extremely high voltage pulses of short duration and high repetition rate are applied between the anode and cathode of the x-ray tube to provide an electron discharge of low energy density below. (google.com)
  • There is less crystal charging from Bremsstrahlung radiation, although there is some from the emission of Auger electrons, and there is significantly less than if the primary beam was itself an electron beam. (wikipedia.org)
  • The discrepancy between the model estimates and hard X-ray observations suggests that electron acceleration can occur not only in the coronal part of a loop but also in the footpoints. (berkeley.edu)
  • Using free-electron x-ray laser experiments a precursor state to desorption is detected and also found in simulations if van der Waals effects are included. (diva-portal.org)
  • A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. (innovations-report.com)
  • In a new study, led by Petra Fromme and Nadia Zatsepin at the Biodesign Center for Applied Structural Discovery, the School of Molecular Sciences and the Department of Physics at ASU, researchers investigated the structure of Photosystem I (PSI) with ultrashort X-ray pulses at the European X-ray Free Electron Laser (EuXFEL), located in Hamburg, Germany. (innovations-report.com)
  • Graphic shows the basic design of an X-ray free electron laser or XFEL, in which brilliant X-ray bursts strike crystallized samples, causing diffraction patterns that can be reassembled into detailed images. (innovations-report.com)
  • An XFEL (for X-ray free-electron laser) delivers X-ray light that is a billion times brighter than conventional X-ray-sources. (innovations-report.com)
  • Upon selective excitation using monochromatic synchrotron radiation in the Cl K -edge (Cl 1s) near-threshold region, polarization-selective x-ray emission studies reveal highly polarized molecular valence x-ray fluorescence for all four molecules. (unlv.edu)
  • The degree and the orientation of the polarized emission are observed to be sensitive to the incident excitation energy near the Cl K edge. (unlv.edu)
  • In some cases, the polarization direction for x-ray emission reverses for small changes in incident excitation energy (a few eV). (unlv.edu)
  • The amplitude of the square-wave output from the inverter is varied in response to the operation of a series regulator selectively controlled by the composite output of a summing amplifier having inputs corresponding to filament current, desired MA, and space charge compensation prior to excitation of the X-ray tube but only to the actual MA compared against a reference potential during excitation. (google.com)
  • A broad peak at about 82.3 eV is tentatively assigned to transitions resulting from Kr/sup 2 +/, and effects of excitation energy on M/sub 4,5/ x-ray emission were observed. (unt.edu)
  • nanocrystals exhibited strong red emission under 970-nm excitation. (spiedigitallibrary.org)
  • The IGRB comprises all extragalactic emissions too faint or too diffuse to be resolved in a given survey, as well as any residual Galactic foregrounds that are approximately isotropic. (diva-portal.org)
  • POLARIS FID SE (PF-300SE) is the evolution of our bestseller Polaris FID, the on-site portable TOC Analyser for Stack Emissions in compliance with EN12619, EN13526 and EPA METHOD 25A. (environmental-expert.com)
  • Integrating during the period 2011-05-28 07:58:37 UT to 2011-05-29 06:02:51 UT (MJD=55709.33-55710.25) the AGILE-GRID detected gamma-ray emission above 100 MeV from a source at Galactic coordinates (l, b) = (79.8, 0.3) +/- 0.8 (stat.) +/- 0.1 (syst. (astronomerstelegram.org)
  • For the 64 other GRBs localized during the period July 2007 to October 2009 in the field of view of the AGILE Gamma-Ray Imaging Detector (GRID), but not detected by this instrument, we estimate the count and flux upper limits on the GRB high energy emission in the AGILE-GRID energy band (30 MeV-3 GeV). (diva-portal.org)
  • DEXA scanning is more accurate than other methods (e.g. plain X-ray): quick, non-invasive, exposes the subject to less radiation and is relatively inexpensive. (thefreedictionary.com)
  • With this source it is possible to use high-harmonic radiation for x-ray absorption. (ebscohost.com)
  • From the flux upper limits derived in this work we put some constraint on high-energy radiation from the afterglow emission and from synchrotron self Compton emission in internal shocks. (diva-portal.org)
  • This fact, together with the detected photon indices, suggests that in LS I +61 303 the X-rays are the result of synchrotron radiation of the same electrons that produce VHE emission as a result of inverse Compton scattering of stellar photons. (arxiv.org)
  • The gamma-ray sky can be decomposed into individually detected sources, diffuse emission attributed to the interactions of Galactic cosmic rays with gas and radiation fields, and a residual all-sky emission component commonly called the isotropic diffuse gamma-ray background (IGRB). (diva-portal.org)
  • We argue that the X-ray emission comes from collisionally ionized material, originally cold gas that has been shock heated by the passage of the radio jet, rather than being photoionized by nuclear radiation. (oup.com)
  • It was known that the radiation leaving an X-ray tube was heterogeneous and dependent on the material of the anti-cathode. (iucr.org)
  • The hardness of this radiation depends on the voltage applied to the X-ray tube. (iucr.org)
  • The emission of the electronic component of the secondary radiation was shown to be closely linked to the K- and L-series. (iucr.org)
  • As mentioned above, these earlier researches on characteristic X-radiation were carried out by using the fluorescence method with an ordinary X-ray tube as primary source. (iucr.org)
  • 24.3/angstrom/) radiation from a conventional x-ray source. (unt.edu)
  • In our view, we can shed light on this issue based on the relationship between hard X-ray emissions from the coronal part (looptop) of a flare loop and its footpoints. (berkeley.edu)
  • This Nugget is devoted to the analysis of the hard X-ray emission from different parts of a flare loop based on RHESSI observations for the well-studied solar flare of 2013-Nov-09 06:26:09, SOL2013-11-09 (C1.2) [1, (berkeley.edu)
  • The hard X-ray images (Figure 1) of the solar flare SOL2013-11-09 (C2.6) show three sources . (berkeley.edu)
  • One of them was located between two others and characterized by the strong hard X-ray emission dominated in some time intervals. (berkeley.edu)
  • These estimates apply at the time of maximum of the hard X-ray emission (06:25:41~UT) in terms of the simultaneous Hinode / EIS observations . (berkeley.edu)
  • The estimate thus obtained contradicts the observed intensities of the hard X-ray sources in the energy range 23.0-27.5 keV (see Fig.1) and demonstrates that the standard solar flare model requires at least some modifications. (berkeley.edu)
  • Note that an extended acceleration region in the corona does not significantly improve the relationship (1) since the generation of the hard X-ray emission in the coronal part will be more effective in this case. (berkeley.edu)
  • We notice that the hard X-ray lightcurve of Cygnus X-3 as monitored by the BAT/Swift instrument (public data available at http:///heasarc.gsfc.nasa.gov/docs/swift/results/transients/CygX-3 ) shows an overall decreasing trend starting on MJD ~ 55680. (astronomerstelegram.org)
  • This trend of decreasing hard X-ray emission in conjunction with gamma-ray flaring activity of Cygnus X-3 was already detected several times (Tavani et al. (astronomerstelegram.org)
  • Impulsive extreme-ultraviolet and hard X-ray emission during solar flares. (harvard.edu)
  • 0.075) active galactic nuclei (AGN), selected in the hard X-ray band (14-195 keV) from the Swift-Burst Alert Telescope survey.With the launch of the James Webb Space Telescope, this regime is of increasing importance for dusty and obscured AGN surveys. (ufrgs.br)
  • We find that the correlation between the hard X-ray and the [Si VI] coronal line luminosity is significantly better than with the [OIII] λ5007 luminosity. (ufrgs.br)
  • In addition, we observe potential soft X-ray emissions via ACIS around 0.2 keV that are correlated in intensity to the hard X-ray emissions between 0.4-1.0 keV. (uconn.edu)
  • We present Chandra X-ray observations of the powerful radio galaxy 3C 171, which reveal an extended region of X-ray emission spatially associated with the well-known 10-kpc scale optical emission-line region around the radio jets. (oup.com)
  • The soft x-ray emission from plasma produced in polyacetal and polyethylene capillary discharges excited by current pulses 100 ns full-width half-maximum (FWHM), 50 ns risetime, and peak currents up to 60 kA has been studied. (colostate.edu)
  • Boron K-edge soft x-ray emission and absorption are used to address the fundamental question of whether divalent hexaborides are intrinsic semimetals or defect-doped bandgap insulators. (unt.edu)
  • X-ray microdiffraction study of Cu interconnects. (ebscohost.com)
  • We have used x-ray microdiffraction to study the local structure and strain variation of copper interconnects. (ebscohost.com)
  • It is suggested that the x-ray polarized-fluorescence phenomenon, reported here for simple molecules, can be used as a new approach to study more complicated systems in a variety of environments. (unlv.edu)
  • The study found that over 13,000 deaths and tens of thousands of cases of chronic bronchitis, acute bronchitis, asthma, congestive heart failure, acute myocardial infarction, dysrhythmia, ischemic heart disease, chronic lung disease, and pneumonia each year are attributable to fine particle pollution from U.S. coal plant emissions. (sourcewatch.org)
  • A comprehensive experimental and theoretical study of the X-ray emission from the valence band of Mn coordination complexes was carried out. (esrf.eu)
  • The extended X-ray absorption fine structure (EXAFS) can provide valuable information on bond lengths, but is usually insensitive to H atoms and limited when distinguishing between ligands with similar atomic numbers (C/N/O). We have performed an experimental and theoretical study of the X-ray emission lines just below the Fermi level after creation of a 1s core hole (valence-to-core XES) in Mn complexes. (esrf.eu)
  • After a short study of ultrasound imaging, you will learn about the different X-ray imaging techniques. (epfl.ch)
  • Here we show on a typical 24 kWh lithium-manganese-oxide-graphite battery pack that the degradation of EV battery can be mathematically modeled to predict battery life and to study its effects on energy consumption and GHG emissions from EV operations. (nature.com)
  • Climate change}} Ray D. Nixon Power Plant is a coal-fired power station owned and operated by the City of Colorado Springs, Colorado. (sourcewatch.org)
  • Similarities between the density of lesions and surrounding breast tissue, in addition to x-ray opacity, limit effective detection of small to medium sized tumors in these patients. (grantome.com)
  • The discovery of very high energy (VHE) gamma-ray emitting X-ray binaries has triggered an intense effort to better understand the particle acceleration, absorption, and emission mechanisms in compact binary systems, which provide variable conditions along eccentric orbits. (arxiv.org)
  • We detect a simultaneous outburst at X-ray and VHE bands, with the peak at phase 0.62 and a similar shape at both wavelengths. (arxiv.org)
  • A linear fit to the simultaneous X-ray/VHE pairs obtained during the outburst yields a correlation coefficient of r=0.97, while a linear fit to all simultaneous pairs provides r=0.81. (arxiv.org)
  • This section applies to the control of employee exposure to coke oven emissions, except that this section shall not apply to working conditions with regard to which other Federal agencies exercise statutory authority to prescribe or enforce standards affecting occupational safety and health. (osha.gov)
  • Coke oven emissions means the benzene-soluble fraction of total particulate matter present during the destructive distillation or carbonization of coal for the production of coke. (osha.gov)
  • Emergency means any occurrence such as, but not limited to, equipment failure which is likely to, or does, result in any massive release of coke oven emissions. (osha.gov)
  • Green plush means coke which when removed from the oven results in emissions due to the presence of unvolatilized coal. (osha.gov)
  • The employer shall assure that no employee in the regulated area is exposed to coke oven emissions at concentrations greater than 150 micrograms per cubic meter of air (150 ug/m 3 ), averaged over any 8-hour period. (osha.gov)
  • Each employer who has a place of employment where coke oven emissions are present shall monitor employees employed in the regulated area to measure their exposure to coke oven emissions. (osha.gov)
  • The employer shall obtain measurements which are representative of each employee's exposure to coke oven emissions over an eight-hour period. (osha.gov)
  • The PBD is making new, state-of-the-art measurements of the wavelengths of select atomic X-ray emission lines. (nist.gov)
  • These measurements underpin all precision x-ray diffraction work. (nist.gov)
  • Precise knowledge of the shape and position of x-ray emission lines is the basis of connecting x-ray diffraction measurements to the Système Internationale d'Unités (SI) , the official worldwide standard for making any measurement. (nist.gov)
  • Measurements of position of x-ray emission lines have been made been made over a long period of time. (nist.gov)
  • at NIST on the x-ray optical interferometer (XROI) (see, for example, Update on crystal lattice measurements at NIST ), that provided an absolute measurement of the lattice constant of silicon, that these measurements have been able to be made in a manner directly traceable to base units of the SI. (nist.gov)
  • The space in which it is located is ideally suited to precision X-ray line measurements, since it is very well temperature controlled, to 0.01C, and isolated from most sources of environmental interference. (nist.gov)
  • The use of an X-ray camera to digitize the diffracted X-rays makes it possible to characterize the optical aberrations which have previously set limits on such measurements. (nist.gov)
  • X-ray and ion measurements in laser produced plasma from gold-copper alloy targets. (ebscohost.com)
  • We find that emission-line diagnostics in the NIR are ineffective at identifying bright, nearby AGN galaxies because [Fe II] 1.257 μm/Paβ and H2 2.12 μm/Brγ identify only 25 per cent (25/102) as AGN with significant overlap with star-forming galaxies and only 20 per cent of Seyfert 2 have detected coronal lines (6/30). (ufrgs.br)
  • This hot plasma is also responsible for the depolarization at low frequencies of the radio emission from the jet and hotspots, which allows us to estimate the. (oup.com)
  • We show that it is likely that both the cold emission-line gas and the hot plasma in which it is embedded are being driven out of the host galaxy of 3C 171 at supersonic speeds. (oup.com)
  • Our results also demonstrate the utility of charge-exchange emissions as a remote diagnostics tool of both astrophysical plasma interaction and solar wind composition. (uconn.edu)
  • Improvements in event selection and characterization of cosmic-ray backgrounds, better understanding of the diffuse Galactic emission (DGE), and a longer data accumulation of 50 months allow for a refinement and extension of the IGRB measurement with the LAT, now covering the energy range from 100 MeV to 820 GeV. (diva-portal.org)
  • The total x rays over an energy range of 4-20 keV, which were mainly assigned to bremsstrahlung, showed forward emission particularly at s-polarized incidence and the characteristic x rays (Cu Kα emission) were almost isotropic. (ebscohost.com)
  • The impulsive EUV emission varies with the central meridian distance of the flare, with a peak in EUV intensity for flares near the central meridian and a marked decline in intensity near the solar limb. (harvard.edu)
  • Synthesis, emission characteristics, cellular studies, and bioconjugat" by Man Wai Ray Louie, Alex Wing Tat Choi et al. (edu.hk)
  • An optical emission spectrometric method for major element determination and an X-ray fluorescence method for the determination of trace elements are described. (ngu.no)
  • Si L[subscript 2,emission features are observed above the conventional Si valence band maximum, with intensity scaling linearly with S concentration. (mit.edu)
  • X-ray angiography perfusion (XAP) is a perfusion imaging technique based on conventional DSA. (ovid.com)
  • Electric vehicles (EVs) are widely promoted as clean alternatives to conventional vehicles for reducing greenhouse gas (GHG) emissions from ground transportation. (nature.com)