Sensory isolation

Because ketamine comes in an iniectahle form and because many of its users are medical personnel, it tends to he taken by injection, usually intramuscularly Given in this way it produces an altered state of consciousness that begins in a few minutes and lasts about half an hour. The feeling is one of dreamy, floating disconnection from external reality. Some ketamine enthusiasts like to cake it while lying in sensory isolation tanks in attempts to have out-of-the-body experiences. 

Sensory isolation tank An oblong, lightproof, soundproof tank partially filled with a strong salt solution maintained at body temperature A person floating in the tank experiences little outside stimulation and can explore inner states Used for relaxation and meditation as well as to investigate altered states of consciousness. 

Self-exploration through drugs, 16 Semisynthetic drugs, 33-34 Sensory isolation tanks, 139 Sernyl, Sernylan, 137-38 Serotonin, 30 Set... 

The development of precise and reproducible methods of sensory analysis is prerequisite to the determination of what causes flavor, or the study of flavor chemistry. Knowing what chemical compounds are responsible for flavor allows the development of analytical techniques using chemistry rather than human subjects to characterize flavor (38,39). Routine analysis in most food production for the quaUty control of flavor is rare (40). Once standards for each flavor quaUty have been synthesized or isolated, they can also be used to train people to do more rigorous descriptive analyses. 

This example demonstrates the most challenging problem of flavor chemistry, ie, each flavor problem may require its own analytical approach however, a sensory analysis is always required. The remaining unknown odorants demand the most sensitive and selective techniques, and methods of concentration and isolation that preserve the sensory properties of complex and often dehcate flavors. Furthermore, some of the subtle odors in one system will be first identified in very different systems, like o-amino acetophenone in weasels and fox grapes. 

Local anesthetics produce anesthesia by blocking nerve impulse conduction in sensory, as well as motor nerve, fibers. Nerve impulses are initiated by membrane depolarization, effected by the opening of a sodium ion channel and an influx of sodium ions. Local anesthetics act by inhibiting the channel s opening they bind to a receptor located in the channel s interior. The degree of blockage on an isolated nerve depends not only on the amount of dmg, but also on the rate of nerve stimulation (153—156). 

R = / -C H ), in low doses, exhibits the former behavior and is used primarily as an extradural agent in obstetrics. The lowest effective extradural concentration of etidocaine (21, X = CH, R = R = 2H, R = / -C H ), however, shows both adequate sensory and profound motor blockade so that it is useful in surgical situations where maximum neuromuscular blockade is necessary. In an isolated nerve preparation, bupivacaine blocks unmyelinated C fibers which are mainly responsible for pain perception at a much greater extent than the myelinated A fibers which carry motor impulses. It is postulated that absorption of bupivacaine by the vasculature at the site of injection, combined with the slow diffusion of this agent, results in an insufficient amount of the drug penetrating the large A fibers to cause motor conduction blockade. Clinically, motor block can be observed in some procedures. 

There have been a number of different synthetic approaches to substituted PTV derivatives proposed in the last decade. Almost all focus on the aromatic ring as the site for substitution. Some effort has been made to apply the traditional base-catalyzed dehydrohalogenation route to PTV and its substituted analogs. The methodology, however, is not as successful for PTV as it is for PPV and its derivatives because of the great tendency for the poly(u-chloro thiophene) precursor spontaneously to eliminate at room temperature. Swager and co-workers attempted this route to synthesize a PTV derivative substituted with a crown ether with potential applications as a sensory material (Scheme 1-26) [123]. The synthesis employs a Fager condensation [124] in its initial step to yield diol 78. Treatment with a ditosylate yields a crown ether-functionalized thiophene diester 79. This may be elaborated to dichloride 81, but pure material could not be isolated and the dichloride monomer had to be polymerized in situ. The polymer isolated... 

Our studies of the absorption, permeation, and extraction properties of containers produced from high nitrile barrier resins have demonstrated that they meet or surpass the basic criteria established for retention of taste and odor characteristics of carbonated soft drinks. Sensory tests, which can isolate and identify end results as well as integrate collective effects, have confirmed this judgement and have established the general compatibility of these containers with a variety of beverage products from a taste and odor standpoint. Furthermore, these materials have the excellent physical properties required for containers which will find wide use in food and beverage packaging. 

British Standard Institution, Methods for the Sensory Analysis of Foods, BS 5929-10 1999/ISOl 1037 1999, London, 1999. 

Cole, D.F. (1984). Sensory and neural mechanisms in contraction of the rabbit isolated spincter pupillae. Exp. Eye Res. 38, 153-163. 

The purpose of preparative-scale liquid chromatography is the isolation of materials conforming to a specified purity in cUBOunts that depend on the intended use of the product [8,570-572]. Possible uses Include the isolation of materials for structural elucidation, for biological or sensory evaluation, for organic synthesis or commercial applications. The scale of the... 

Among the many sensory reactions Phycomyces displays, the study of the photoreceptor and adaptation deserves maximal attention, since Phycomyces shares these two attributes with a variety of other blue light sensitive organisms. Action-spectroscopy indicates a flavin as the photoreceptor of Phycomyces. /3-carotene was positively ruled out as a possible receptor, since mutants with no trace amounts of )3-carotene are phototropical normal. The photoreceptor has not yet been isolated. As in other systems the difficulty consists in distinguishing the flavin photoreceptor from the bulk flavoproteins in the cell. One therefore needs unambiguous criteria for the identification of the photoreceptor. The most promising approach for an isolation would be a photoreceptor mutant and we described the properties those mutants should have. Until now there is no firm evidence that the photomutants, madA or madB are defective in the photoreceptor. 

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