785 research outputs found

    Insertion/deletion-related polymorphisms in the human T cell receptor beta gene complex.

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    Insertion/deletion related polymorphisms (IDRP) involving stretches of 15-30 kb within the human TCR-beta gene complex were revealed by pulse-field gel electrophoresis. Two independent IDRP systems were detected by analysis of Sfi I- and Sal I-digested human DNA samples using probes for TCR C and V region gene segments. The allelic nature of these systems was verified in family studies, and mapping data allowed localization of one area of insertion/deletion among the V gene segments and the other near the C region genes. All but one of 50 individuals tested could be typed for the two allelic systems, and gene frequencies for the two allelic forms were 0.37/0.61 and 0.46/0.54, indicating that these polymorphisms are widespread

    Orienting versus inhibition in the concealed information test: different cognitive processes drive different physiological measures

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    The Concealed Information Test (CIT) provides a valid tool for psychophysiological detection of concealed knowledge. However, its precise theoretical underpinnings remain a matter of debate. The differential physiological responses elicited by concealed, relevant items, relative to control items, were traditionally explained as reflecting an orienting response (OR). According to an alternative account, these responses reflect attempts to inhibit arousal. The present study examined whether and to what extent CIT detection efficiency is affected by instructions aimed at manipulating arousal inhibition (AI). One hundred and forty-eight undergraduate students completed a CIT, while electrodermal, cardiac, and respiratory measures were recorded. Half of the participants were requested to imagine that they are suspected of committing a crime and were motivated to avoid detection (presumably eliciting both OR and AI), while the other half were requested to imagine that they are witnesses of a crime and were motivated to be detected (presumably eliciting OR only). All participants were further requested to remain silent throughout the test. In both conditions, concealed items led to a similar increase in skin conductance as compared to the control items. However, the typically observed heart rate deceleration and respiratory suppression were found in suspects, but not in witnesses. These data imply that different mechanisms drive the responding of different psychophysiological measures used in the CIT, with skin conductance reflecting OR, and heart rate and respiration primarily reflecting AI

    VRA Modeling, phase 1

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    The destruction of organic contaminants in waste water for closed systems, such as that of Space Station, is crucial due to the need for recycling the waste water. A co-current upflow bubble column using oxygen as the gas phase oxidant and packed with catalyst particles consisting of a noble metal on an alumina substrate is being developed for this process. The objective of this study is to develop a plug-flow model that will predict the performance of this three phase reactor system in destroying a multicomponent mixture of organic contaminants in water. Mass balances on a series of contaminants and oxygen in both the liquid and gas phases are used to develop this model. These mass balances incorporate the gas-to-liquid and liquid-to-particle mass transfer coefficients, the catalyst effectiveness factor, and intrinsic reaction rate. To validate this model, a bench scale reactor has been tested at Michigan Technological University at elevated pressures (50-83 psig,) and a temperature range of 200 to 290 F. Feeds consisting of five dilute solutions of ethanol (approx. 10 ppm), chlorobenzene (approx. 20 ppb), formaldehyde (approx. 100 ppb), dimethyl sulfoxide (DMSO approx. 300 ppb), and urea (approx. 20 ppm) in water were tested individually with an oxygen mass flow rate of 0.009 lb/h. The results from these individual tests were used to develop the kinetic parameter inputs necessary for the computer model. The computer simulated results are compared to the experimental data obtained for all 5 components run in a mixture on the differential test column for a range of reactor contact times

    Prolonged dexamethasone exposure enhances zebrafish lateral-line regeneration but disrupts mitochondrial homeostasis and hair cell function

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    The synthetic glucocorticoid dexamethasone is commonly used to treat inner ear disorders. Previous work in larval zebrafish has shown that dexamethasone treatment enhances hair cell regeneration, yet dexamethasone has also been shown to inhibit regeneration of peripheral nerves after lesion. We therefore used the zebrafish model to determine the impact of dexamethasone treatment on lateral-line hair cells and primary afferents. To explore dexamethasone in the context of regeneration, we used copper sulfate (CuS

    The effects of primary elevation of cerebral venous pressure on cerebral hemodynamics and intracranial pressure

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23634/1/0000598.pd
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