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Olfactometer
An olfactometer is an instrument used to detect and measure odor dilution. Olfactometers are used in conjunction with human subjects in laboratory settings, most often in market research, to quantify and qualify human olfaction. Olfactometers are used to gauge the odor detection threshold of substances. To measure intensity, olfactometers introduce an odorous gas as a baseline against which other odors are compared. Many scientists use the term "olfactometer" to refer to a device used to study insect behavior in presence of an olfactory stimulus. It consists of a tube with a bifurcation (with "T" or "Y" shape) where an insect walks and decides between two choices, usually clean air versus air carrying an odor. This is why this device is also called dual choice olfactometer. Alternatively, an olfactometer is a device used for producing aromas in a precise and controlled manner. Flow-olfactometer Description A flow-olfactometer is a difficult instrument for creation of well d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odor
An odor (American English) or odour (English in the Commonwealth of Nations, Commonwealth English; American and British English spelling differences#-our, -or, see spelling differences) is caused by one or more volatilized chemical compounds that are generally found in low concentrations that humans and animals can perceive via their sense of Sense of smell, smell. An odor is also called a "smell" or a "scent", which can refer to either a pleasant or an unpleasant odor. While "odor" and "smell" can refer to pleasant and unpleasant odors, the terms "scent", "aroma", and "fragrance" are usually reserved for pleasant-smelling odors and are frequently used in the food and cosmetic industry to describe floral scents or to refer to perfumes. Physiology of smell Sense of smell The perception of odors, or sense of smell, is mediated by the olfactory nerve. The olfactory receptor (OR) cells are neurons present in the olfactory epithelium, which is a small patch of tissue at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olfaction
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it occurs when an odor binds to a receptor within the nasal cavity, transmitting a signal through the olfactory system. Glomeruli aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain responsible for smell identification, memory, and emotion. There are many different causes for alteration, lack, or disturbance to a normal sense of smell, and can include damage to the nose or smell receptors, or central problems affecting the brain. Some causes include upper respiratory infections, traumatic brain injury, and neurodegenerative disease. History of study Early scientific study of the sense of smell includes the extensive doctoral dissertation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olfaction
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it occurs when an odor binds to a receptor within the nasal cavity, transmitting a signal through the olfactory system. Glomeruli aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain responsible for smell identification, memory, and emotion. There are many different causes for alteration, lack, or disturbance to a normal sense of smell, and can include damage to the nose or smell receptors, or central problems affecting the brain. Some causes include upper respiratory infections, traumatic brain injury, and neurodegenerative disease. History of study Early scientific study of the sense of smell includes the extensive doctoral dissertation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entomologist Donald Barnard Demonstrates The Attraction Of Female Yellow Fever Mosquitoes To His Hand In An Olfactometer
Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as arachnids, myriapods, and crustaceans. This wider meaning may still be encountered in informal use. Like several of the other fields that are categorized within zoology, entomology is a taxon-based category; any form of scientific study in which there is a focus on insect-related inquiries is, by definition, entomology. Entomology therefore overlaps with a cross-section of topics as diverse as molecular genetics, behavior, neuroscience, biomechanics, biochemistry, systematics, physiology, developmental biology, ecology, morphology, and paleontology. Over 1.3 million insect species have been described, more than two-thirds of all known species. Some insect species date back to around 400 million years ago. They have many kinds of intera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Market Research
Market research is an organized effort to gather information about target markets and customers: know about them, starting with who they are. It is an important component of business strategy and a major factor in maintaining competitiveness. Market research helps to identify and analyze the needs of the market, the market size and the competition. Its techniques encompass both qualitative techniques such as focus groups, in-depth interviews, and ethnography, as well as quantitative techniques such as customer surveys, and analysis of secondary data. It includes social and opinion research, and is the systematic gathering and interpretation of information about individuals or organizations using statistical and analytical methods and techniques of the applied social sciences to gain insight or support decision making. Market research, marketing research, and marketing are a sequence of business activities; sometimes these are handled informally. The field of ''marketing researc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odor Detection Threshold
The odor detection threshold is the lowest concentration of a certain odor compound that is perceivable by the human sense of smell. The threshold of a chemical compound is determined in part by its shape, polarity, partial charges, and molecular mass. The olfactory mechanisms responsible for a compound's different detection threshold is not well understood. As such, odor thresholds cannot be accurately predicted. Rather, they must be measured through extensive tests using human subjects in laboratory settings. Optical isomers can have different detection thresholds because their conformations may cause them to be less perceivable for the human nose. It is only in recent years that such compounds were separated on gas chromatographs. For raw water treatment and waste water management, the term commonly used is Threshold Odor Number (TON). For instance, the water to be supplied for domestic use in Illinois is 3 TON. Values * The threshold value is the concentration at which an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evoked Potential
An evoked potential or evoked response is an electrical potential in a specific pattern recorded from a specific part of the nervous system, especially the brain, of a human or other animals following presentation of a Stimulus (physiology), stimulus such as a light flash or a pure tone. Different types of potentials result from stimuli of different Stimulus modality, modalities and types. Evoked potential is distinct from spontaneous potentials as detected by electroencephalography (EEG), electromyography (EMG), or other electrophysiology, electrophysiologic recording method. Such potentials are useful for electrodiagnostic medicine, electrodiagnosis and monitoring (medicine), monitoring that include detections of disease and drug-related sensory dysfunction and intraoperative monitoring of sensory pathway integrity. Evoked potential amplitudes tend to be low, ranging from less than a microvolt to several microvolts, compared to tens of microvolts for EEG, millivolts for EMG, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Ranger
Nasal is an adjective referring to the nose, part of human or animal anatomy. It may also be shorthand for the following uses in combination: * With reference to the human nose: ** Nasal administration, a method of pharmaceutical drug delivery ** Nasal emission, the abnormal passing of oral air through a palatal cleft, or from some other type of pharyngeal inadequacy ** Nasal hair, the hair in the nose * With reference to phonetics: ** Nasalization, the production of a sound with a lowered velum, allowing some of the air to escape through the nose; the resulting being either: *** a nasal consonant, or *** a nasal vowel * With reference to the nose of humans or other animals: ** Nasal bone, two small oblong bones placed side by side at the middle and upper part of the face, and form, by their junction, "the bridge" of the nose ** Nasal cavity, a large air filled space above and behind the nose in the middle of the face ** Nasal concha, a long, narrow and curled bone shelf which p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popular Mechanics
''Popular Mechanics'' (sometimes PM or PopMech) is a magazine of popular science and technology, featuring automotive, home, outdoor, electronics, science, do-it-yourself, and technology topics. Military topics, aviation and transportation of all types, space, tools and gadgets are commonly featured. It was founded in 1902 by Henry Haven Windsor, who was the editor and—as owner of the Popular Mechanics Company—the publisher. For decades, the tagline of the monthly magazine was "Written so you can understand it." In 1958, PM was purchased by the Hearst Corporation, now Hearst Communications. In 2013, the US edition changed from twelve to ten issues per year, and in 2014 the tagline was changed to "How your world works." The magazine added a podcast in recent years, including regular features ''Most Useful Podcast Ever'' and ''How Your World Works''. History ''Popular Mechanics'' was founded in Chicago by Henry Haven Windsor, with the first issue dated January 11, 1902. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASTM
ASTM International, formerly known as American Society for Testing and Materials, is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services. Some 12,575 ASTM voluntary consensus standards operate globally. The organization's headquarters is in West Conshohocken, Pennsylvania, about northwest of Philadelphia. It is founded in 1902 as the American Section of the International Association for Testing Materials (see also International Organization for Standardization). History A group of scientists and engineers, led by Charles Dudley, formed ASTM in 1898 to address the frequent rail breaks affecting the fast-growing railroad industry. The group developed a standard for the steel used to fabricate rails. Originally called the "American Society for Testing Materials" in 1902, it became the "American Society for Testing And Materials" in 1961. In 2001, ASTM official ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Nose
An electronic nose is an electronic sensing device intended to detect odors or flavors. The expression "electronic sensing" refers to the capability of reproducing human senses using sensor arrays and pattern recognition systems. Since 1982, research has been conducted to develop technologies, commonly referred to as electronic noses, that could detect and recognize odors and flavors. The stages of the recognition process are similar to human olfaction and are performed for identification, comparison, quantification and other applications, including data storage and retrieval. Some such devices are used for industrial purposes. Other techniques to analyze odors In all industries, odor assessment is usually performed by human sensory analysis, by chemosensors, or by gas chromatography. The latter technique gives information about volatile organic compounds but the correlation between analytical results and mean odor perception is not direct due to potential interactions between s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrogustometry
Electrogustometry is the measurement of taste threshold by passing controlled anodal current through the tongue. When current passes through the tongue a unique and distinct metallic taste is perceived. Electrogustometry has been in existence since the 1950s. However, not much research has been done in this field. Equipment TR Bull developed an electrogustometer, but it lacked precision and was not widely accepted. In the 1990s the Rion (TR-06) was developed. This was precise and is widely used in the market. The TR-06 is probably the only electrogustometer used now for research and diagnosis. This is manual and needs a trained doctor or nurse to use it. It needs to be manually calculated to arrive at the taste threshold and carry out the false positive tests. Small, light and portable, this hand-held, battery-powered device can be easily placed in any environment. It has an inbuilt false positive detect test. This is developed to cater for the psychophysical analysis of the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
