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Singular they
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Cognitive efficiency
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A study of whether "singular they" is more "difficult" to understand than gendered pronouns found that "singular they is a cognitively efficient substitute for generic he or she, particularly when the antecedent is nonreferential" (e.g. anybody, a nurse, or a truck driver) rather than referring to a specific person (e.g. a runner I knew or my nurse). Clauses with singular they were read "just as quickly as clauses containing a gendered pronoun that matched the stereotype of the antecedent" (e.g. she for a nurse and he for a truck driver) and "much more quickly than clauses containing a gendered pronoun that went against the gender stereotype of the antecedent".On the other hand, when the pronoun they was used to refer to known individuals ("referential antecedents, for which the gender was presumably known", e.g. my nurse, that truck driver, a runner I knew), reading was slowed when compared with use of a gendered pronoun consistent with the "stereotypic gender" (e.g. he for a specific truck driver).The study concluded that "the increased use of singular they is not problematic for the majority of readers".
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Singular they
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Comparison with other pronouns
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The singular and plural use of they can be compared with the pronoun you, which had been both a plural and polite singular, but by the 18th century replaced thou for singular referents. For "you", the singular reflexive pronoun ("yourself") is different from its plural reflexive pronoun ("yourselves"); with "they" one can hear either "themself" or "themselves" for the singular reflexive pronoun.
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Singular they
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Comparison with other pronouns
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Singular "they" has also been compared to nosism (such as the "royal we"), when a single person uses first-person plural in place of first-person singular pronouns. Similar to singular "you", its singular reflexive pronoun ("ourself") is different from the plural reflexive pronoun ("ourselves").
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Singular they
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Comparison with other pronouns
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While the pronoun set derived from it is primarily used for inanimate objects, it is frequently used in an impersonal context when someone's identity is unknown or established on a provisional basis, e.g. "Who is it?" or "With this new haircut, no one knows it is me." It is also used for infants of unspecified gender but may be considered dehumanizing and is therefore more likely in a clinical context. Otherwise, in more personal contexts, the use of it to refer to a person might indicate antipathy or other negative emotions.It can also be used for non-human animals of unspecified sex, though they is common for pets and other domesticated animals of unspecified sex, especially when referred to by a proper name (e.g. Rags, Snuggles). Normally, birds and mammals with a known sex are referred to by their respective male or female pronoun (he and she; him and her).
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Singular they
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In other languages
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In German, some nonbinary people use they/them pronouns as an anglicism, for want of an established German gender-neutral pronoun. they in German comes with verbs in singular ("they ist", i.e. "they is"), since there is no plural they in German. In French some prefer to use iel instead of il or elle
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Permanganate
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Permanganate
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A permanganate () is a chemical compound with the manganate(VII) ion, MnO−4, the conjugate base of permanganic acid. Because the manganese atom has a +7 oxidation state, the permanganate(VII) ion is a strong oxidising agent. The ion is a transition metal ion with a tetrahedral structure. Permanganate solutions are purple in colour and are stable in neutral or slightly alkaline media. The exact chemical reaction depends on the carbon-containing reactants present and the oxidant used. For example, trichloroethane (C2H3Cl3) is oxidised by permanganate ions to form carbon dioxide (CO2), manganese dioxide (MnO2), hydrogen ions (H+), and chloride ions (Cl−).
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Permanganate
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Permanganate
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8MnO−4 + 3C2H3Cl3 → 6CO2 + 8MnO2 + H+ + 4H2O + 9Cl−In an acidic solution, permanganate(VII) is reduced to the pale pink manganese(II) (Mn2+) with an oxidation state of +2.
8 H+ + MnO−4 + 5 e− → Mn2+ + 4 H2OIn a strongly basic or alkaline solution, permanganate(VII) is reduced to the green manganate ion, MnO2−4 with an oxidation state of +6.
MnO−4 + e− → MnO2−4In a neutral solution, however, it gets reduced to the brown manganese dioxide MnO2 with an oxidation state of +4.
2 H2O + MnO−4 + 3 e− → MnO2 + 4 OH−
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Permanganate
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Production
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Permanganates can be produced by oxidation of manganese compounds such as manganese chloride or manganese sulfate by strong oxidizing agents, for instance, sodium hypochlorite or lead dioxide: 2 MnCl2 + 5 NaClO + 6 NaOH → 2 NaMnO4 + 9 NaCl + 3 H2O 2 MnSO4 + 5 PbO2 + 3 H2SO4 → 2 HMnO4 + 5 PbSO4 + 2 H2OIt may also be produced by the disproportionation of manganates, with manganese dioxide as a side-product: 3 Na2MnO4 + 2 H2O → 2 NaMnO4 + MnO2 + 4 NaOHThey are produced commercially by electrolysis or air oxidation of alkaline solutions of manganate salts (MnO2−4).
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Permanganate
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Usage
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This is a common and strong disinfectant, used regularly to sanitize baths, toilets, and wash basins, or anything general like that. It is a cheap and extremely effective compound for the task.
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Permanganate
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Properties
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Permanganates(VII) are salts of permanganic acid. They have a deep purple colour, due to a charge transfer transition from oxo ligand p orbitals to empty orbitals derived from manganese(VII) d orbitals. Permanganate(VII) is a strong oxidizer, and similar to perchlorate. It is therefore in common use in qualitative analysis that involves redox reactions (permanganometry). According to theory, permanganate is strong enough to oxidize water, but this does not actually happen to any extent. Besides this, it is stable.
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Permanganate
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Properties
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It is a useful reagent, but it is not very selective with organic compounds. Potassium permanganate is used as a disinfectant and water treatment additive in aquaculture.Manganates(VII) are not very stable thermally. For instance, potassium permanganate decomposes at 230 °C to potassium manganate and manganese dioxide, releasing oxygen gas: 2 KMnO4 → K2MnO4 + MnO2 + O2A permanganate can oxidize an amine to a nitro compound, an alcohol to a ketone, an aldehyde to a carboxylic acid, a terminal alkene to a carboxylic acid, oxalic acid to carbon dioxide, and an alkene to a diol. This list is not exhaustive.
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Permanganate
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Properties
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In alkene oxidations one intermediate is a cyclic Mn(V) species:
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Permanganate
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Compounds
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Ammonium permanganate, NH4MnO4 Barium permanganate, Ba(MnO4)2 Calcium permanganate, Ca(MnO4)2 Potassium permanganate, KMnO4 Sodium permanganate, NaMnO4 Silver permanganate, AgMnO4
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AnyKode Marilou
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AnyKode Marilou
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anyKode Marilou is a modeling and simulation environment for mobile robots, humanoids, articulated arms and parallel robots operating in real-world conditions that respect the laws of physics. This robotics suite is used in research centers and industry for various projects like humanoid architectures, wheeled and multi legged vehicles, and multi-robot systems (Multi-agents).
It also has a real-time engine that uses the ODE (Open Dynamics Engine) for collisions detecting and dynamics management. Various 'real world' variables like forces, torques, masses, damping, friction and others can be adjusted directly to the objects surfaces.
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AnyKode Marilou
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Scenes modeling
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The entities' editor can design the robot's collision model by using any of the static or dynamic objects in the given simulated world. CAD-style editing tools are entirely graphical.
Scenes, dynamics, and robots properties can be changed from a view/document/properties IHM style. Also, the editor takes in charge re-usable physicals entities as well as pure 3D models.
Marilou uses a hierarchical system to present entire objects at the highest level (the current world). This approach makes it possible to reuse members of a complex object as sub-parts of another object.
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AnyKode Marilou
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Key features
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Graphical handling of robots and environments models (physics parts and 3D models) Modeling helpers, Refactoring tools, several documents and viewpoints Rigid bodies, n-axis constraints and springs Mechanical constraints Surface properties (reflection, shock, friction, incidence, rebound, behavior with infra-red or ultrasound …) Hierarchy and complex assemblies Real-time or accelerated simulations (RT-Multiplier) Multi-robots, multiple embedded applications, centralized or distributed Acquisition/measurement cycles as low as 1 ms Interactions with running simulation 3D rendering using pixel and vertex shaders Spot, Point, Ambient and Directional lights Dynamic shadowing Physics Editor for Windows, Exec (the simulator) for Windows, Ubuntu, and Mint (BETA)
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AnyKode Marilou
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Devices
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Marilou includes a complete set of user-modifiable virtual devices. The behavior of these devices may be overridden by the properties of real devices available in robotics. This feature allows the programmer to use a known device's parameters directly.
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AnyKode Marilou
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Devices
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This is a list of supported devices types: Embedded robotic components Absolute Compass Actuating cylinders / jack Accelerometers/Gyro-meters/Gyroscope Air pressure forces Bumpers Distance sensors (Ultrasonic, Infra Red and Laser) Motors and servo motors Emitters and receivers Force and Torque sensors GPS Laser range finders LED LCD display Light Sources Lidar (3D-Scanner) Odometers Standard and panoramic spherical Cameras (Panoramic camera) Touch area
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AnyKode Marilou
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Robots programming
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MODA (Marilou Open Devices Access) is the Marilou generic SDK for handling simulated robots and their embedded devices, such as sensors and actuators. Depending on chosen language, MODA provides libraries (.lib /.a) or .Net assembly (.dll) for accessing simulation over the network. Synchronized to a simulated clock, algorithms can run on any computer in the network. Individual robots may run several programs. In addition, one MODA program can control numerous robots, whether they be in the same world. MODA TCP server can be embedded in real robot.
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AnyKode Marilou
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Robots programming
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Languages: C / C++, C++ CLI, C#, J#, VB# Compilers: Microsoft Visual Studio suites, DevC++, Borland C++ RAD Studio, G++ for Linux, CodeBlocks MODA is open-source and compatible with Linux (Mac coming soon)
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Anomalous oxygen
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Anomalous oxygen
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Anomalous oxygen is hot atomic and singly ionized oxygen believed to be present in Earth's exosphere above 500 km near the poles during their respective summers. This additional component augmenting mainly the hydrogen and helium exosphere is able to explain the unexpectedly high drag forces on satellites passing near the poles in their summers. Anomalous oxygen densities are included in the NRLMSISE-00 models of Earth's atmosphere.
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Sandalore
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Sandalore
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Sandalore is a synthetic sandalwood odorant with odor in some ways similar to sandalwood and consequently used in perfumes, emollients, and skin cleaning agents. Sandalore, and the similar brahmanol, have been identified as agonists of the cutaneous olfactory receptor OR2AT4, and found to induce strong Ca2+ signals in cultured human keratinocytes. The long-term stimulation of keratinocytes with Sandalore positively affected cell proliferation and migration, and regeneration of keratinocyte monolayers in an in vitro wound scratch assay (i.e., sandalore stimulation also enhanced epidermal "wound healing" in human skin organ cultures). Natural sandalwood oil and other synthetic sandalwood odorants did not have the same effect.
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Anti-NMDA receptor encephalitis
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Anti-NMDA receptor encephalitis
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Anti-NMDA receptor encephalitis is a type of brain inflammation caused by antibodies. Early symptoms may include fever, headache, and feeling tired. This is then typically followed by psychosis which presents with false beliefs (delusions) and seeing or hearing things that others do not see or hear (hallucinations). People are also often agitated or confused. Over time, seizures, decreased breathing, and blood pressure and heart rate variability typically occur. In some cases, patients may develop catatonia.About half of cases are associated with tumors, most commonly teratomas of the ovaries. Another established trigger is herpesviral encephalitis, while the cause in others cases is unclear. The underlying mechanism is autoimmune, with the primary target being the GluN1 subunit of the N-methyl D-aspartate receptors (NMDAR) in the brain. Diagnosis is typically based on finding specific antibodies in the cerebral spinal fluid. MRI of the brain is often normal. Misdiagnosis is common.Treatment is typically with immunosuppresive medication and, if a tumor is present, surgery to remove it. With treatment, about 80% of cases have a good outcome. Outcomes are better if treatment is begun earlier. Long-term mental or behavioral problems may remain. About 4% of those affected die from the condition. Recurrence occurs in about 10% of people.The estimated number of cases of the disease is one in 1.5 million people per year. The condition is relatively common compared to other paraneoplastic disorders. About 80% of those affected are female. It typically occurs in adults younger than 45 years old, but it can occur at any age. The disease was first described by Josep Dalmau in 2007.
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Anti-NMDA receptor encephalitis
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Signs and symptoms
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Prior to the development of a symptom complex that is specific to anti-NMDA receptor encephalitis, people may experience prodromal symptoms, including headaches, flu-like illness, or symptoms similar to an upper respiratory infection. These symptoms may be present for weeks or months prior to disease onset. Beyond the prodromal symptoms, the disease progresses at varying rates, and patients may present with a variety of neurological symptoms. During the initial stage of the disease, symptoms vary slightly between children and adults. However, behavior changes are a common first symptom within both groups. These changes often include agitation, paranoia, psychosis, and violent behaviors. Other common manifestations include seizures and bizarre movements, mostly of the lips and mouth, but also including pedaling motions with the legs or hand movements resembling playing a piano. Some other symptoms typical during the disease onset include impaired cognition, memory deficits, and speech problems (including aphasia, perseveration or mutism).The symptoms usually appear psychiatric in nature, which may confound the differential diagnosis. In many cases, this leads to the illness going undiagnosed. As the disease progresses, the symptoms become medically urgent and often include autonomic dysfunction, hypoventilation, cerebellar ataxia, loss of feeling on one side of the body, loss of consciousness, or catatonia. During this acute phase, most patients require treatment in an intensive care unit to stabilize breathing, heart rate, and blood pressure. One distinguishing characteristic of anti-NMDA receptor encephalitis is the concurrent presence of many of the above listed symptoms. The majority of patients experience at least four symptoms, with many experiencing six or seven over the course of the disease.
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Anti-NMDA receptor encephalitis
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Pathophysiology
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The condition is mediated by autoantibodies that target NMDA receptors in the brain. These can be produced by cross reactivity with NMDA receptors in teratomas, which contain many cell types, including brain cells, and thus present a window in which a breakdown in immunological tolerance can occur. Other autoimmune mechanisms are suspected for patients who do not have tumors. Whilst the exact pathophysiology of the disease is still debated, empirical evaluation of the origin of anti-NMDA receptor antibodies in serum and cerebrospinal fluid leads to the consideration of two possible mechanisms.These mechanisms may be informed by some simple observations. Serum NMDA receptor antibodies are consistently found at higher concentrations than cerebrospinal fluid antibodies, on average ten times higher. This strongly suggests the antibody production is systemic rather than in the brain or cerebrospinal fluid. When concentrations are normalized for total IgG, intrathecal synthesis is detected. This implies that there are more NMDA receptor antibodies in the cerebrospinal fluid than would be predicted given the expected quantities of total IgG.
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Anti-NMDA receptor encephalitis
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Pathophysiology
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Passive access involves the diffusion of antibodies from the blood across a pathologically disrupted blood-brain barrier (BBB). This cellular filter, separating the central nervous system from the circulatory system, normally prevents larger molecules from entering the brain. A variety of reasons for such a collapse in integrity have been suggested, with the most likely answer being the effects of acute inflammation of the nervous system. Likewise, the involvement of corticotropin releasing hormone on mast cells in acute stress has been shown to facilitate BBB penetration. However, it is also possible that the autonomic dysfunction manifested in many patients during the later phases of the condition aids antibody entry. For example, an increase in blood pressure would force larger proteins, such as antibodies, to extravasate into the cerebrospinal fluid.
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Anti-NMDA receptor encephalitis
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Pathophysiology
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Intrathecal production (production of antibodies in the intrathecal space) is also a possible mechanism. Dalmau et al. demonstrated that 53 out of 58 patients with the condition had at least partially preserved BBBs, whilst having a high concentration of antibodies in the cerebrospinal fluid. Furthermore, cyclophosphamide and rituximab, drugs used to eliminate dysfunctional immune cells, have been shown to be successful second-line treatments in patients where first-line immunotherapy has failed. These destroy excess antibody-producing cells in the thecal sac, thus alleviating the symptoms.A more sophisticated analysis of the processes involved in antibody presence in the cerebrospinal fluid hints at a combination of these two mechanisms in tandem.
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Anti-NMDA receptor encephalitis
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Pathophysiology
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Antibodies Once the antibodies have entered the CSF, they bind to the NR1 subunit of the NMDA receptor. There are three possible methods in which neuronal damage occurs.
A reduction in the density of NMDA receptors on the post synaptic knob, due to receptor internalization once the antibody has bound. This is dependent on antibodies cross linking.
The direct antagonism of the NMDA receptor by the antibody, similar to the action of the classic dissociative anesthetics phencyclidine and ketamine.
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Anti-NMDA receptor encephalitis
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Pathophysiology
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The recruitment of the complement cascade via the classical pathway (antibody-antigen interaction). Membrane attack complex (MAC) is one of the end products of this cascade and can insert into neurons as a molecular barrel, allowing water to enter. The cell subsequently lyses. Notably, this mechanism is unlikely as it causes the cell to die, which is inconsistent with current evidence.
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Anti-NMDA receptor encephalitis
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Diagnosis
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First and foremost is a high level of clinical suspicion, especially in young adults showing abnormal behavior as well as autonomic instability. Clinical examination may further reveal delusions and hallucinations, which can aid diagnostic efforts.The initial investigation usually consists of clinical examination, MRI of the brain, an EEG, and a lumbar puncture for CSF analysis. MRI of the brain may show abnormalities in the temporal and frontal lobes, but do so in less than half of cases. A FDG-PET scan of the brain may show abnormalities in cases when the MRI scan is normal. EEG is abnormal in almost 90% of cases and typically shows general or focal slow wave activity. CSF analysis often shows inflammatory changes with increased levels of white blood cells, total protein and the presence of oligoclonal bands. NMDA receptor antibodies can be detected in serum and/or CSF. Whole body FDG-PET is usually performed as a part of tumor screening. Gynecological ultrasound or a pelvic MRI might be performed to search for an ovarian teratoma in women.
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Anti-NMDA receptor encephalitis
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Diagnosis
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Diagnostic criteria for probable and definite anti-NMDA receptor encephalitis have been proposed to facilitate diagnosis at an early stage of the disease and help initiate early treatment.
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Anti-NMDA receptor encephalitis
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Management
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If a person is found to have a tumor, the long-term prognosis is generally better and the chance of relapse is much lower. This is because the tumor can be removed surgically, thus eradicating the source of autoantibodies. In general, early diagnosis and aggressive treatment is believed to improve patient outcomes, but this remains impossible to know without data from randomized controlled trials. Given that the majority of patients are initially seen by psychiatrists, it is critical that all physicians (especially psychiatrists) consider anti-NMDA receptor encephalitis as a possible cause of acute psychosis in young patients with no past neuropsychiatric history.
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Anti-NMDA receptor encephalitis
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Management
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If a tumor is detected, its removal should occur in conjunction with first-line immunotherapy. This involves steroids to suppress the immune system, intravenous immunoglobulin, and plasmapheresis to physically remove autoantibodies. A study of 577 patients showed that over four weeks, about half the patients improved after receiving first-line immunotherapy.
Second-line immunotherapy includes rituximab, a monoclonal antibody that targets the CD20 receptor on the surface of B cells, thus destroying the self-reactive B cells. Cyclophosphamide, an alkylating agent that cross-links DNA and is used to treat both cancer and autoimmune diseases, has sometimes proven useful when other therapies have failed.
Other medications, such as alemtuzumab, remain experimental.
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Anti-NMDA receptor encephalitis
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Prognosis
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The recovery process from anti-NMDAR encephalitis can take many months. The symptoms may reappear in reverse order: The patient may begin to experience psychosis again, leading many people to falsely believe the patient is not recovering. As the recovery process continues on, the psychosis fades. Lastly, the person's social behavior and executive functions begin to improve.
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Anti-NMDA receptor encephalitis
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Epidemiology
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The estimated number of cases of the disease is 1.5 per million people per year. According to the California Encephalitis Project, the disease has a higher incidence than its individual viral counterparts in patients younger than 30. The largest case series as of 2013 characterized 577 people with anti-NMDA receptor encephalitis. The data were limited, but provides the best approximation of disease distribution. It found that women make up 81% of cases. Disease onset is skewed toward children, with a median age of diagnosis of 21 years. Over a third of cases were children, while only 5% of cases were patients over the age of 45. This same review found that 394 out of 501 patients (79%) had a good outcome by 24 months. 30 people (6%) died, and the rest were left with mild to severe deficits. The study mentioned that of the 38% presenting with tumors, 94% of those presented with ovarian teratomas. Within that subset, African & Asian women were more likely to have a tumor, but this was not relevant to the prevalence of the disease within those racial groups.
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Anti-NMDA receptor encephalitis
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Society and culture
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Anti-NMDA receptor encephalitis is suspected of being an underlying cause of historical accounts of demonic possession.New York Post reporter Susannah Cahalan wrote a book titled Brain on Fire: My Month of Madness about her experience with the disease. This has subsequently been turned into a film of the same name.Dallas Cowboys defensive lineman Amobi Okoye spent 17 months battling anti-NMDA receptor encephalitis. In addition to three months in a medically-induced coma, he experienced a 145-day memory gap and lost 78 pounds. He returned to practice on October 23, 2014.In the Japanese movie called The 8-Year Engagement, a young Japanese woman ends up being in a coma due to anti-NMDA receptor encephalitis.
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Anti-NMDA receptor encephalitis
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Society and culture
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Knut, a polar bear at the Berlin Zoological Garden that died on 19 March 2011, was diagnosed with anti-NMDA receptor encephalitis in August 2015. This was the first case discovered in a non-human animal.In Hannibal, Will Graham was affected by NMDA receptor or antibody encephalitis, also known as anti-NMDAR encephalitis.The TV series Something's Killing Me featured an episode called "Into Madness" that featured two cases of the disease.
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Carnitine-acylcarnitine translocase
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Carnitine-acylcarnitine translocase
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Carnitine-acylcarnitine translocase (CACT) is responsible for passive transport of carnitine and carnitine-fatty acid complexes and across the inner mitochondrial membrane as part of the carnitine shuttle system.
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Carnitine-acylcarnitine translocase
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Function
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Fatty acyl–carnitine can diffuse from the cytosol across the porous outer mitochondrial membrane to the intermembrane space, but must utilize CACT to cross the nonporous inner mitochondrial membrane and reach the mitochondrial matrix. CACT is a cotransporter, returning one molecule of carnitine from the matrix to the intermembrane space as one molecule of fatty acyl–carnitine moves into the matrix.
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Carnitine-acylcarnitine translocase
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Clinical significance
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A disorder is associated with carnitine-acylcarnitine translocase deficiency. This disorder disrupts the carnitine shuttle system from moving fatty acids across the mitochondrial membrane, leading to a decrease in fatty acid catabolism. The result is an accumulation of fatty acid within muscles and liver, decreased tolerance to long term exercise, inability to fast for more than a few hours, muscle weakness and wasting, and a strong acidic smell on the breath (due to protein catabolism).
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Carnitine-acylcarnitine translocase
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Model organisms
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Model organisms have been used in the study of SLC25A20 function. A conditional knockout mouse line called Slc25a20tm1a(EUCOMM)Wtsi was generated at the Wellcome Trust Sanger Institute. Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion. Additional screens performed: - In-depth immunological phenotyping
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Antaryamin
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Antaryamin
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The Antaryamin, in terms of Hindu philosophy, is related to the "inner-self", the "inner-controller" or the "inner-guidance" that exists in a person and itself manifests on an intuitive way to the one manifesting it. It recalls a teacher or a guru that resides within and once it is manifested - for a higher context of knowledge guidance - usually after one summons or prays for it, the Antaryamin comes to help. In some cases, the Antaryamin is asked to be manifested in order to resolve non-intellectual issues, also performing miracles to the one asking.
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Antaryamin
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Hindu contextualization
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On the Hindu scriptures, we find the concept of the Antaryamin as the Inner Controller after the building of the elementary concepts regarding a deity or an ego - on a unity way - of which is controlling, somehow to a compared intelligence, the universe and all that is. This intelligence may also refer to what is called consciousness or awareness that is far superior, hence capable of doing superior things.
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Vital signs
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Vital signs
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Vital signs (also known as vitals) are a group of the four to six most crucial medical signs that indicate the status of the body's vital (life-sustaining) functions. These measurements are taken to help assess the general physical health of a person, give clues to possible diseases, and show progress toward recovery. The normal ranges for a person's vital signs vary with age, weight, sex, and overall health.There are four primary vital signs: body temperature, blood pressure, pulse (heart rate), and breathing rate (respiratory rate), often notated as BT, BP, HR, and RR. However, depending on the clinical setting, the vital signs may include other measurements called the "fifth vital sign" or "sixth vital sign". Vital signs are recorded using the LOINC internationally accepted standard coding system.Early warning scores have been proposed that combine the individual values of vital signs into a single score. This was done in recognition that deteriorating vital signs often precede cardiac arrest and/or admission to the intensive care unit. Used appropriately, a rapid response team can assess and treat a deteriorating patient and prevent adverse outcomes.
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Vital signs
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Primary vital signs
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There are four primary vital signs which are standard in most medical settings: Body temperature Heart rate or Pulse Respiratory rate Blood pressureThe equipment needed is a thermometer, a sphygmomanometer, and a watch. Although a pulse can be taken by hand, a stethoscope may be required for a patient with a very weak pulse.
Temperature Temperature recording gives an indication of core body temperature which is normally tightly controlled (thermoregulation) as it affects the rate of chemical reactions. Body temperature is maintained through a balance of the heat produced by the body and the heat lost from the body.
Temperature can be recorded in order to establish a baseline for the individual's normal body temperature for the site and measuring conditions.
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Vital signs
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Primary vital signs
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Temperature can be measured from the mouth, rectum, axilla (armpit), ear, or skin. Oral, rectal, and axillary temperature can be measured with either a glass or electronic thermometer. Note that rectal temperature measures approximately 0.5 °C higher than oral temperature, and axillary temperature approximately 0.5 °C less than oral temperature. Aural and skin temperature measurements require special devices designed to measure temperature from these locations.While 37 °C (98.6 °F) is considered "normal" body temperature, there is some variance between individuals. Most have a normal body temperature set point that falls within the range of 36.0 °C to 37.5 °C (96.5–99.5 °F).The main reason for checking body temperature is to solicit any signs of systemic infection or inflammation in the presence of a fever. Fever is considered temperature of 37.8 °C or above. Other causes of elevated temperature include hyperthermia, which results from unregulated heat generation or abnormalities in the body's heat exchange mechanisms.Temperature depression (hypothermia) also needs to be evaluated. Hypothermia is classified as temperature below 35 °C (95 °F).It is also recommended to review the trend of the patient's temperature over time. A fever of 38 °C does not necessarily indicate an ominous sign if the patient's previous temperature has been higher.
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Vital signs
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Primary vital signs
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Pulse The pulse is the rate at which the heart beats while pumping blood through the arteries, recorded as beats per minute (bpm). It may also be called "heart rate". In addition to providing the heart rate, the pulse should also be evaluated for strength and obvious rhythm abnormalities. The pulse is commonly taken at the wrist (radial artery). Alternative sites include the elbow (brachial artery), the neck (carotid artery), behind the knee (popliteal artery), or in the foot (dorsalis pedis or posterior tibial arteries). The pulse is taken with the index finger and middle finger by pushing with firm yet gentle pressure at the locations described above, and counting the beats felt per 60 seconds (or per 30 seconds and multiplying by two). The pulse rate can also be measured by listening directly to the heartbeat using a stethoscope. The pulse may vary due to exercise, fitness level, disease, emotions, and medications. The pulse also varies with age. A newborn can have a heart rate of 100–160 bpm, an infant (0–5 months old) a heart rate of 90–150 bpm, and a toddler (6–12 months old) a heart rate of 80–140 bpm. A child aged 1–3 years old can have a heart rate of 80–130 bpm, a child aged 3–5 years old a heart rate of 80–120 bpm, an older child (age of 6–10) a heart rate of 70–110 bpm, and an adolescent (age 11–14) a heart rate of 60–105 bpm. An adult (age 15+) can have a heart rate of 60–100 bpm.
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Vital signs
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Primary vital signs
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Respiratory rate Average respiratory rates vary between ages, but the normal reference range for people age 18 to 65 is 16–20 breaths per minute. The value of respiratory rate as an indicator of potential respiratory dysfunction has been investigated but findings suggest it is of limited value. Respiratory rate is a clear indicator of acidotic states, as the main function of respiration is removal of CO2 leaving bicarbonate base in circulation.
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Vital signs
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Primary vital signs
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Blood pressure Blood pressure is recorded as two readings: a higher systolic pressure, which occurs during the maximal contraction of the heart, and the lower diastolic or resting pressure. In adults, a normal blood pressure is 120/80, with 120 being the systolic and 80 being the diastolic reading. Usually, the blood pressure is read from the left arm unless there is some damage to the arm. The difference between the systolic and diastolic pressure is called the pulse pressure. The measurement of these pressures is now usually done with an aneroid or electronic sphygmomanometer. The classic measurement device is a mercury sphygmomanometer, using a column of mercury measured off in millimeters. In the United States and UK, the common form is millimeters of mercury, while elsewhere SI units of pressure are used. There is no natural 'normal' value for blood pressure, but rather a range of values that on increasing are associated with increased risks. The guideline acceptable reading also takes into account other co-factors for disease. Therefore, elevated blood pressure (hypertension) is variously defined when the systolic number is persistently over 140–160 mmHg. Low blood pressure is hypotension. Blood pressures are also taken at other portions of the extremities. These pressures are called segmental blood pressures and are used to evaluate blockage or arterial occlusion in a limb (see Ankle brachial pressure index).
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Vital signs
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Other signs
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In the U.S., in addition to the above four, many providers are required or encouraged by government technology-in-medicine laws to record the patient's height, weight, and body mass index. In contrast to the traditional vital signs, these measurements are not useful for assessing acute changes in state because of the rate at which they change; however, they are useful for assessing the impact of prolonged illness or chronic health problems.
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Vital signs
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Other signs
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The definition of vital signs may also vary with the setting of the assessment. Emergency medical technicians (EMTs), in particular, are taught to measure the vital signs of respiration, pulse, skin, pupils, and blood pressure as "the 5 vital signs" in a non-hospital setting.
Fifth vital signs The "fifth vital sign" may refer to a few different parameters.
Pain is considered a standard fifth vital sign in some organizations, such as the U.S. Veterans Affairs. Pain is measured on a 0–10 pain scale based on subjective patient reporting and may be unreliable. Some studies show that recording pain routinely may not change management.
Menstrual cycle Oxygen saturation (as measured by pulse oximetry) Blood glucose level Sixth vital signs There is no standard "sixth vital sign"; its use is more informal and discipline-dependent.
End-tidal CO2 Functional status Shortness of breath Gait speed Delirium
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Vital signs
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Variations by age
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Children and infants have respiratory and heart rates that are faster than those of adults as shown in the following table :
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Vital signs
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Monitoring
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Monitoring of vital parameters most commonly includes at least blood pressure and heart rate, and preferably also pulse oximetry and respiratory rate. Multimodal monitors that simultaneously measure and display the relevant vital parameters are commonly integrated into the bedside monitors in intensive care units, and the anesthetic machines in operating rooms. These allow for continuous monitoring of a patient, with medical staff being continuously informed of the changes in the general condition of a patient.
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Vital signs
|
Monitoring
|
While monitoring has traditionally been done by nurses and doctors, a number of companies are developing devices that can be used by consumers themselves. These include Cherish Health, Scanadu and Azoi.
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Electromagnetic pulse
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Electromagnetic pulse
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An electromagnetic pulse (EMP), also referred to as a transient electromagnetic disturbance (TED), is a brief burst of electromagnetic energy. The origin of an EMP can be natural or artificial, and can occur as an electromagnetic field, as an electric field, as a magnetic field, or as a conducted electric current. The electromagnetic interference caused by an EMP can disrupt communications and damage electronic equipment. An EMP such as a lightning strike can physically damage objects such as buildings and aircraft. The management of EMP effects is a branch of electromagnetic compatibility (EMC) engineering.
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Electromagnetic pulse
|
Electromagnetic pulse
|
The first recorded damage from an electromagnetic pulse came with the solar storm of August 1859, or the Carrington Event.In modern warfare, weapons delivering a high energy EMP pulse are designed to disrupt communications equipment, the computers needed to operate modern warplanes, or even put the entire electrical network of a target country out of commission.
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Electromagnetic pulse
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General characteristics
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An electromagnetic pulse is a short surge of electromagnetic energy. Its short duration means that it will be spread over a range of frequencies. Pulses are typically characterized by: The mode of energy transfer (radiated, electric, magnetic or conducted).
The range or spectrum of frequencies present.
Pulse waveform: shape, duration and amplitude.The frequency spectrum and the pulse waveform are interrelated via the Fourier transform which describes how component waveforms may sum to the observed frequency spectrum.
Types of energy EMP energy may be transferred in any of four forms: Electric field Magnetic field Electromagnetic radiation Electrical conductionAccording to Maxwell's equations, a pulse of electric energy will always be accompanied by a pulse of magnetic energy. In a typical pulse, either the electric or the magnetic form will dominate.
In general, radiation only acts over long distances, with the magnetic and electric fields acting over short distances. There are a few exceptions, such as a solar magnetic flare.
Frequency ranges A pulse of electromagnetic energy typically comprises many frequencies from very low to some upper limit depending on the source. The range defined as EMP, sometimes referred to as "DC to daylight", excludes the highest frequencies comprising the optical (infrared, visible, ultraviolet) and ionizing (X and gamma rays) ranges.
Some types of EMP events can leave an optical trail, such as lightning and sparks, but these are side effects of the current flow through the air and are not part of the EMP itself.
Pulse waveforms The waveform of a pulse describes how its instantaneous amplitude (field strength or current) changes over time. Real pulses tend to be quite complicated, so simplified models are often used. Such a model is typically described either in a diagram or as a mathematical equation.
Most electromagnetic pulses have a very sharp leading edge, building up quickly to their maximum level. The classic model is a double-exponential curve which climbs steeply, quickly reaches a peak and then decays more slowly. However, pulses from a controlled switching circuit often approximate the form of a rectangular or "square" pulse.
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Electromagnetic pulse
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General characteristics
|
EMP events usually induce a corresponding signal in the surrounding environment or material. Coupling usually occurs most strongly over a relatively narrow frequency band, leading to a characteristic damped sine wave. Visually it is shown as a high frequency sine wave growing and decaying within the longer-lived envelope of the double-exponential curve. A damped sinewave typically has much lower energy and a narrower frequency spread than the original pulse, due to the transfer characteristic of the coupling mode. In practice, EMP test equipment often injects these damped sinewaves directly rather than attempting to recreate the high-energy threat pulses.
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Electromagnetic pulse
|
General characteristics
|
In a pulse train, such as from a digital clock circuit, the waveform is repeated at regular intervals. A single complete pulse cycle is sufficient to characterise such a regular, repetitive train.
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Electromagnetic pulse
|
Types
|
An EMP arises where the source emits a short-duration pulse of energy. The energy is usually broadband by nature, although it often excites a relatively narrow-band damped sine wave response in the surrounding environment. Some types are generated as repetitive and regular pulse trains.
Different types of EMP arise from natural, man-made, and weapons effects.
Types of natural EMP events include: Lightning electromagnetic pulse (LEMP). The discharge is typically an initial current flow of perhaps millions of amps, followed by a train of pulses of decreasing energy.
Electrostatic discharge (ESD), as a result of two charged objects coming into proximity or even contact.
Meteoric EMP. The discharge of electromagnetic energy resulting from either the impact of a meteoroid with a spacecraft or the explosive breakup of a meteoroid passing through the Earth's atmosphere.
Coronal mass ejection (CME), sometimes referred to as a solar EMP. A burst of plasma and accompanying magnetic field, ejected from the solar corona and released into the solar wind.Types of (civil) man-made EMP events include: Switching action of electrical circuitry, whether isolated or repetitive (as a pulse train).
Electric motors can create a train of pulses as the internal electrical contacts make and break connections as the armature rotates.
Gasoline engine ignition systems can create a train of pulses as the spark plugs are energized or fired.
Continual switching actions of digital electronic circuitry.
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Electromagnetic pulse
|
Types
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Power line surges. These can be up to several kilovolts, enough to damage electronic equipment that is insufficiently protected.Types of military EMP include: Nuclear electromagnetic pulse (NEMP), as a result of a nuclear explosion. A variant of this is the high altitude nuclear EMP (HEMP), which produces a secondary pulse due to particle interactions with the Earth's atmosphere and magnetic field.
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Electromagnetic pulse
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Types
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Non-nuclear electromagnetic pulse (NNEMP) weapons.
Lightning Lightning is unusual in that it typically has a preliminary "leader" discharge of low energy building up to the main pulse, which in turn may be followed at intervals by several smaller bursts.
Electrostatic discharge (ESD) ESD events are characterized by high voltages of many kV, but small currents sometimes cause visible sparks. ESD is treated as a small, localized phenomenon, although technically a lightning flash is a very large ESD event. ESD can also be man-made, as in the shock received from a Van de Graaff generator.
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Electromagnetic pulse
|
Types
|
An ESD event can damage electronic circuitry by injecting a high-voltage pulse, besides giving people an unpleasant shock. Such an ESD event can also create sparks, which may in turn ignite fires or fuel-vapour explosions. For this reason, before refueling an aircraft or exposing any fuel vapor to the air, the fuel nozzle is first connected to the aircraft to safely discharge any static.
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Electromagnetic pulse
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Types
|
Switching pulses The switching action of an electrical circuit creates a sharp change in the flow of electricity. This sharp change is a form of EMP.
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Electromagnetic pulse
|
Types
|
Simple electrical sources include inductive loads such as relays, solenoids, and brush contacts in electric motors. These typically send a pulse down any electrical connections present, as well as radiating a pulse of energy. The amplitude is usually small and the signal may be treated as "noise" or "interference". The switching off or "opening" of a circuit causes an abrupt change in the current flowing. This can in turn cause a large pulse in the electric field across the open contacts, causing arcing and damage. It is often necessary to incorporate design features to limit such effects.
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Electromagnetic pulse
|
Types
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Electronic devices such as vacuum tubes or valves, transistors, and diodes can also switch on and off very quickly, causing similar issues. One-off pulses may be caused by solid-state switches and other devices used only occasionally. However, the many millions of transistors in a modern computer may switch repeatedly at frequencies above 1 GHz, causing interference that appears to be continuous.
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Electromagnetic pulse
|
Types
|
Nuclear electromagnetic pulse (NEMP) A nuclear electromagnetic pulse is the abrupt pulse of electromagnetic radiation resulting from a nuclear explosion. The resulting rapidly changing electric fields and magnetic fields may couple with electrical/electronic systems to produce damaging current and voltage surges.The intense gamma radiation emitted can also ionize the surrounding air, creating a secondary EMP as the atoms of air first lose their electrons and then regain them.
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Electromagnetic pulse
|
Types
|
NEMP weapons are designed to maximize such EMP effects as the primary damage mechanism, and some are capable of destroying susceptible electronic equipment over a wide area.
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Electromagnetic pulse
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Types
|
A high-altitude electromagnetic pulse (HEMP) weapon is a NEMP warhead designed to be detonated far above the Earth's surface. The explosion releases a blast of gamma rays into the mid-stratosphere, which ionizes as a secondary effect and the resultant energetic free electrons interact with the Earth's magnetic field to produce a much stronger EMP than is normally produced in the denser air at lower altitudes.
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Electromagnetic pulse
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Types
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Non-nuclear electromagnetic pulse (NNEMP) Non-nuclear electromagnetic pulse (NNEMP) is a weapon-generated electromagnetic pulse without use of nuclear technology. Devices that can achieve this objective include a large low-inductance capacitor bank discharged into a single-loop antenna, a microwave generator, and an explosively pumped flux compression generator. To achieve the frequency characteristics of the pulse needed for optimal coupling into the target, wave-shaping circuits or microwave generators are added between the pulse source and the antenna. Vircators are vacuum tubes that are particularly suitable for microwave conversion of high-energy pulses.NNEMP generators can be carried as a payload of bombs, cruise missiles (such as the CHAMP missile) and drones, with diminished mechanical, thermal and ionizing radiation effects, but without the consequences of deploying nuclear weapons.
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Electromagnetic pulse
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Types
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The range of NNEMP weapons is much less than nuclear EMP. Nearly all NNEMP devices used as weapons require chemical explosives as their initial energy source, producing only one millionth the energy of nuclear explosives of similar weight. The electromagnetic pulse from NNEMP weapons must come from within the weapon, while nuclear weapons generate EMP as a secondary effect. These facts limit the range of NNEMP weapons, but allow finer target discrimination. The effect of small e-bombs has proven to be sufficient for certain terrorist or military operations. Examples of such operations include the destruction of electronic control systems critical to the operation of many ground vehicles and aircraft.The concept of the explosively pumped flux compression generator for generating a non-nuclear electromagnetic pulse was conceived as early as 1951 by Andrei Sakharov in the Soviet Union, but nations kept work on non-nuclear EMP classified until similar ideas emerged in other nations.
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Electromagnetic pulse
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Effects
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Minor EMP events, and especially pulse trains, cause low levels of electrical noise or interference which can affect the operation of susceptible devices. For example, a common problem in the mid-twentieth century was interference emitted by the ignition systems of gasoline engines, which caused radio sets to crackle and TV sets to show stripes on the screen. Laws were introduced to make vehicle manufacturers fit interference suppressors.At a high voltage level an EMP can induce a spark, for example from an electrostatic discharge when fuelling a gasoline-engined vehicle. Such sparks have been known to cause fuel-air explosions and precautions must be taken to prevent them.A large and energetic EMP can induce high currents and voltages in the victim unit, temporarily disrupting its function or even permanently damaging it.A powerful EMP can also directly affect magnetic materials and corrupt the data stored on media such as magnetic tape and computer hard drives. Hard drives are usually shielded by heavy metal casings. Some IT asset disposal service providers and computer recyclers use a controlled EMP to wipe such magnetic media.A very large EMP event such as a lightning strike or a air bursted nuclear weapon, is also capable of damaging objects such as trees, buildings and aircraft directly, either through heating effects or the disruptive effects of the very large magnetic field generated by the current. An indirect effect can be electrical fires caused by heating. Most engineered structures and systems require some form of protection against lightning to be designed in. A good means of protection is a Faraday shield designed to protect certain items from being destroyed.
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Electromagnetic pulse
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Control
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Like any electromagnetic interference, the threat from EMP is subject to control measures. This is true whether the threat is natural or man-made.
Therefore, most control measures focus on the susceptibility of equipment to EMP effects, and hardening or protecting it from harm. Man-made sources, other than weapons, are also subject to control measures in order to limit the amount of pulse energy emitted.
The discipline of ensuring correct equipment operation in the presence of EMP and other RF threats is known as electromagnetic compatibility (EMC).
Test simulation To test the effects of EMP on engineered systems and equipment, an EMP simulator may be used.
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Electromagnetic pulse
|
Control
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Induced pulse simulation Induced pulses are of much lower energy than threat pulses and so are more practicable to create, but they are less predictable. A common test technique is to use a current clamp in reverse, to inject a range of damped sine wave signals into a cable connected to the equipment under test. The damped sine wave generator is able to reproduce the range of induced signals likely to occur.
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Electromagnetic pulse
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Control
|
Threat pulse simulation Sometimes the threat pulse itself is simulated in a repeatable way. The pulse may be reproduced at low energy in order to characterise the subject's response prior to damped sinewave injection, or at high energy to recreate the actual threat conditions. A small-scale ESD simulator may be hand-held. Bench- or room-sized simulators come in a range of designs, depending on the type and level of threat to be generated.
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Electromagnetic pulse
|
Control
|
At the top end of the scale, large outdoor test facilities incorporating high-energy EMP simulators have been built by several countries. The largest facilities are able to test whole vehicles including ships and aircraft for their susceptibility to EMP. Nearly all of these large EMP simulators used a specialized version of a Marx generator. Examples include the huge wooden-structured ATLAS-I simulator (also known as TRESTLE) at Sandia National Labs, New Mexico, which was at one time the world's largest EMP simulator. Papers on this and other large EMP simulators used by the United States during the latter part of the Cold War, along with more general information about electromagnetic pulses, are now in the care of the SUMMA Foundation, which is hosted at the University of New Mexico. The US Navy also has a large facility called the Electro Magnetic Pulse Radiation Environmental Simulator for Ships I (EMPRESS I).
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Electromagnetic pulse
|
Safety
|
High-level EMP signals can pose a threat to human safety. In such circumstances, direct contact with a live electrical conductor should be avoided. Where this occurs, such as when touching a Van de Graaff generator or other highly charged object, care must be taken to release the object and then discharge the body through a high resistance, in order to avoid the risk of a harmful shock pulse when stepping away.
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Electromagnetic pulse
|
Safety
|
Very high electric field strengths can cause breakdown of the air and a potentially lethal arc current similar to lightning to flow, but electric field strengths of up to 200 kV/m are regarded as safe.According to research from Edd Gent, a 2019 report by the Electric Power Research Institute, which is funded by utility companies, found that a large EMP attack would probably cause regional blackouts but not a nationwide grid failure and that recovery times would be similar to those of other large-scale outages. It is not known how long these electrical blackouts would last, or what extent of damage would occur across the country. It is possible that neighboring countries of the U.S. could also be affected by such an attack, depending on the targeted area and people.According to an article from Naureen Malik, with North Korea's increasingly successful missile and warhead tests in mind, Congress moved to renew funding for the Commission to Assess the Threat to the U.S. from Electromagnetic Pulse Attack as part of the National Defense Authorization Act. At the moment, the United States lacks preparation against an EMP attack.According to research from Yoshida Reiji, in a 2016 article for the Tokyo-based nonprofit organization Center for Information and Security Trade Control, Onizuka warned that a high-altitude EMP attack would damage or destroy Japan's power, communications and transport systems as well as disable banks, hospitals and nuclear power plants.
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Electromagnetic pulse
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In popular culture
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By 1981, a number of articles on electromagnetic pulse in the popular press spread knowledge of the EMP phenomenon into the popular culture. EMP has been subsequently used in a wide variety of fiction and other aspects of popular culture. Popular media often depict EMP effects incorrectly, causing misunderstandings among the public and even professionals. Official efforts have been made in the U.S. to remedy these misconceptions.
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Carbocisteine
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Carbocisteine
|
Carbocisteine, also called carbocysteine, is a mucolytic that reduces the viscosity of sputum and so can be used to help relieve the symptoms of chronic obstructive pulmonary disorder (COPD) and bronchiectasis by allowing the sufferer to bring up sputum more easily. Carbocisteine should not be used with antitussives (cough suppressants) or medicines that dry up bronchial secretions.
It was first described in 1951 and came into medical use in 1960. Carbocisteine is produced by alkylation of cysteine with chloroacetic acid.
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Olive oil extraction
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Olive oil extraction
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Olive oil extraction is the process of extracting the olive oil present in olive drupes. Olive oil is produced in the mesocarp cells, and stored in a particular type of vacuole called a lipo vacuole, i.e., every cell contains a tiny olive oil droplet. Olive oil extraction is the process of separating the oil from the other fruit contents (vegetative extract liquid and solid material). It is possible to attain this separation by physical means alone, i.e., oil and water do not mix, so they are relatively easy to separate. This contrasts with other oils that are extracted with chemical solvents, generally hexane. The first operation when extracting olive oil is washing the olives, to reduce the presence of contaminants, especially soil which can create a particular flavor effect called "soil taste".
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Olive oil extraction
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Olive presses
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People have used olive presses since Greeks first began pressing olives over 5,000 years ago. Roman olive presses survive to the present time, with a notable collection present at Volubilis in Morocco. An olive press works by applying pressure to olive paste to separate the liquid oil and vegetation water from the solid material. The oil and vegetation water are then separated by standard decantation.
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Olive oil extraction
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Olive presses
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Olive presses were traditionally built within walled structures. Traditional olive-presses consisted of a large, cylindrical millstone mounted by an upper milling-stone used to grind the olives and their pits into a pulp. Formerly, the upper milling-stone was turned by a beast of burden pulling a wooden beam attached to the stone. After which, the pulp was collected and kneaded. It was then placed within frails (being no more than flexible, woven baskets made of thick fibrous material, usually of rushes, palm fronds, hemp or willow splints), stacked one on top of the other, to which was applied a stone weight to release the oil from the pulp. The extracted liquid which is obtained consists of oil and vegetable water (amurca) mixed together, and runs off into a pit. After settling, the oil rises to the surface and is removed by way of decantation. Filtering the oil produces a clearer batch of oil. The olive residue that remained was used for lighting fires.
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Olive oil extraction
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Olive presses
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This basic method is still widely used today, and it is still a valid way of producing high quality olive oil if adequate precautions are taken.
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Olive oil extraction
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Olive presses
|
First the olives are ground into an olive paste using large millstones at a corporate oil mill. The olive paste generally stays under the stones for 30–40 minutes. This has three objectives: Ensure that olives are well ground Allow enough time for the olive drops to join to form the largest droplets of oil Allow the fruit enzymes to produce some of the oil aromas and tasteOlive oil mills very rarely use a modern crushing method with a traditional press.In modern-day mills, after grinding, the olive paste is spread on fibre discs, which are stacked on top of each other, then placed into the mechanical press. In modern times, these discs are made of synthetic fibres which are easier to clean and maintain.
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Olive oil extraction
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Olive presses
|
These discs are then put on a hydraulic piston, forming a pile. Pressure is applied on the disks, thus compacting the solid phase of the olive paste and percolating the liquid phases (oil and vegetation water). The applied hydraulic pressure can go to 400 atm. To facilitate separation of the liquid phases, water is run down the sides of the discs to increase the speed of percolation. The liquids are then separated either by a standard process of decantation or by means of a faster vertical centrifuge.
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Olive oil extraction
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Olive presses
|
The traditional method is a valid form of producing high-quality olive oil, if after each extraction the discs are properly cleaned from the remains of paste; if not the leftover paste will begin to ferment, thereby producing inconsistencies of flavors (called defects) that will contaminate the subsequently produced olive oil. A similar problem can affect the grindstones that, in order to assure perfect quality, also require cleaning after each usage.
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Olive oil extraction
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Olive presses
|
Grades of olive oil In ancient Palestine and the Levant, three methods were used to produce different grades of olive oil. The finest oil was produced from fully developed and ripe olives harvested solely from the apex of the tree, and lightly pressed, "for what flows from light pressure is very sweet and very thin." The remaining olives are pressed with a heavier weight, and vary in ripeness. Inferior oil is produced from unripe olives that are stored for extended periods of time until they grow soft or begin to shrivel to become more fit for grinding. Others are left for extended periods in pits in the ground to induce sweating and decay before they are ground. According to the Geoponica, salt and a little nitre are added when oil is stored. Traditionally, freshly collected olives were laid up within a large tub (Hebrew: מעטן) and sprinkled with salt before they were to be crushed in the mill, and which function served to heat-up the olives and to induce sweating, thereby bringing them to an advanced stage of ripeness, and make it easier to extract the oil once the olives are brought to the mill.
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Olive oil extraction
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Olive presses
|
Advantages and disadvantages Proper cleaning produces higher-quality oil. Grindstones, while ancient in design, are a suitable way to grind olives, because this method breaks up the drupe's pulp while only slightly touching the nut and the skin. This reduces the release of the oil oxidation enzymes present in these organs. In addition, in this extraction method, the introduction of water is minimal when compared to the modern one, thus reducing the washing-off of the polyphenols. The exhausted paste, called pomace, has a low content of water, making it an easier residue to manage.
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Olive oil extraction
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Olive presses
|
Advantages Better grinding of the olives, reducing the release of oil oxidation enzymes Reduced added water, minimizing the washing of polyphenols Pomace with a low content of water easier to manageDisadvantages Difficult to clean Non-continuous process with waiting periods thus exposes the olive paste to oxygen and light Requires more manual labor Longer production time from harvest to pressing
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Olive oil extraction
|
Decanter centrifugation
|
The modern method of olive oil extraction uses an industrial decanter to separate all the phases by centrifugation. In this method the olives are crushed to a fine paste. This can be done by a hammer crusher, disc crusher, depitting machine or knife crusher. This paste is then malaxed for 30 to 60 minutes in order to allow the small olive droplets to agglomerate. The aromas are created in these two steps through the action of fruit enzymes.
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Olive oil extraction
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Decanter centrifugation
|
Afterwards the paste is pumped into an industrial decanter where the phases will be separated. Water is added to facilitate the extraction process with the paste.
The decanter is a large capacity horizontal centrifuge rotating approximately 3,000 rpm, the high centrifugal force created allows the phases to be readily separated according to their different densities (solids > vegetation water > oil). Inside the decanter's rotating conical drum there is a coil that rotates more slowly, pushing the solid materials out of the system.
The separated oil and vegetation water are then rerun through a vertical centrifuge, working around 6,000 rpm that will separate the small quantity of vegetation water still contained in oil and vice versa.
Three, two, and two and a half phases decanters With the three phases oil decanter, a portion of the oil polyphenols is washed out due to the higher quantity of added water (when compared to the traditional method), producing a larger quantity of vegetation water that needs to be processed.
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Olive oil extraction
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Decanter centrifugation
|
The two phases oil decanter was created as an attempt to solve these problems. Sacrificing part of its extraction capability, it uses less added water thus reducing the phenol washing. The olive paste is separated into two phases: oil and wet pomace. This type of decanter, instead of having three exits (oil, water, and solids), has only two. The water is expelled by the decanter coil together with the pomace, resulting in a wetter pomace that is much harder to process industrially. Many pomace oil extraction facilities refuse to work with these materials because the energy costs of drying the pomace for the hexane oil extraction often make the extraction process sub-economical. In practice, then, the two phases decanter solves the phenol washing problem but increases the residue management problem. This residue management problem has been reduced by the collection of this wetter pomace and being transported to specialized facilities called extractors which heat the pomace between 45 °C and 50 °C and can extract up to a further 2 litres per 100 kilos of pomace using adapted two-phase decanters.
|
Olive oil extraction
|
Decanter centrifugation
|
The two-and-a-half-phase oil decanter is a compromise between the two previous types of decanters. It separates the olive paste into the standard three phases, but has a smaller need for added water and also a smaller vegetation water output. Therefore, the water content of the obtained pomace comes very close to that of the standard three-phase decanter, and the vegetation water output is relatively small, minimizing the residue management issues.
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Olive oil extraction
|
Decanter centrifugation
|
Depending on the olives and processing, the Decanter or Tricanter can extract between 85 and 90% of the olive oil in the 1st extraction. The yield from olive oil manufacture can be increased even further with a 2nd extraction. The olive oil yield increases to as much as 96% by combining the 1st and 2nd extractions.
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Olive oil extraction
|
Decanter centrifugation
|
Advantages and disadvantages Advantages Compact machinery: only one decanter required Continuous and automated Limited labor required Highest percent of oil extraction Vegetable water disposal less of a problem Olive oil from two-phase centrifugation systems contains more phenols, tocopherols, trans‑2‑hexenal, and total aroma compounds and is more resistant to oxidation than oil from three-phase ones and from hydraulic pressesDisadvantages Expensive More technical labor required High energy consumption Pomace may end up moist Greater amount of vegetable water to be disposed of Reduced antioxidants due to added water Subject to wear from rocks, grit
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Olive oil extraction
|
Sinolea method
|
The Sinolea method to extract oil from the olives was introduced in 1972; in this process, rows of metal discs or plates are dipped into the paste; the oil preferentially wets and sticks to the metal and is removed with scrapers in a continuous process. It is based on the different surface tension of the vegetation water and the oil, these different physical behaviors allow the olive oil to adhere to a steel plaque while the other two phases remain behind.
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Olive oil extraction
|
Sinolea method
|
Sinolea works by continuously introducing several hundreds of steel plaques into the paste thus extracting the olive oil. This process is not completely efficient leaving a large quantity of oil still in the paste, so the remaining paste has to be processed by the standard modern method (industrial decanter).
|
Olive oil extraction
|
Sinolea method
|
Advantages and disadvantages Advantages Higher polyphenol content of oil Low temperature method Automated Low labor Oil/water separation step is not needed Low energy requirementDisadvantages Often must be combined with one of the above methods in order to maximize oil extraction which requires more space and labor Large surface areas can lead to rapid oxidation of the olive product Sale of future machines currently outlawed in the European Union due to difficulty in cleaning large surface areas
|
Olive oil extraction
|
First cold pressed – cold extraction
|
Many oils are marketed as first cold pressed or cold extraction. "Cold" means no heat is added during extraction. "Pressed" means that the olives are crushed in a mill to extract the oil.In the EU, these designations are regulated by Article 5 of Commission Regulation (EC) No 1019/2002 of 13 June 2002 on marketing standards for olive oil. This article states that in order to use these designations the olive oil bottler must prove that the temperature of malaxation and extraction was under 27 °C (80 °F).
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