22 research outputs found

    Controlled Ecological Life Support Systems (CELSS) physiochemical waste management systems evaluation

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    Parametric data for six waste management subsystems considered for use on the Space Station are compared, i.e.: (1) dry incineration; (2) wet oxidation; (3) supercritical water oxidation; (4) vapor compression distillation; (5) thermoelectric integrated membrane evaporation system; and (6) vapor phase catalytic ammonia removal. The parameters selected for comparison are on-orbit weight and volume, resupply and return to Earth logistics, power consumption, and heat rejection. Trades studies are performed on subsystem parameters derived from the most recent literature. The Boeing Engineering Trade Study (BETS), an environmental control and life support system (ECLSS) trade study computer program developed by Boeing Aerospace Company, is used to properly size the subsystems under study. The six waste treatment subsystems modeled in this program are sized to process the wastes for a 90-day Space Station mission with an 8-person crew, and an emergency supply period of 28 days. The resulting subsystem parameters are compared not only on an individual subsystem level but also as part of an integrated ECLSS

    Gemeinkosten-Controlling mit SAP® R/3®

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    Structural and chiroptical analysis of naturally occurring (-)-strychnine.

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    Structural aspects such as chemical exchange, dimerization, solvent association, nitrogen inversion and protonation status of strychnine were investigated using experimental and calculated data. The information was mainly interpreted in view of a successful determination of the absolute configuration (AC) with strychnine (base and salt) as test molecule due to its importance in chemistry. By geometry optimization a stable isomer of protonated strychnine was found with an inverted nitrogen, however, 25 kcal/mol higher in energy. It is shown that solvent association can be assumed in protic solvents such as methanol and dimerization to a small extent in polar/protic solvents. However, the monomeric structural model neglecting explicit solvent molecules still allows the correct prediction of the AC of base and hydrochloride using optical rotation and ECD data

    The 5-lipoxygenase inhibitor RF-22c potently suppresses leukotriene biosynthesis in cellulo and blocks bronchoconstriction and inflammation in vivo

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    5-Lipoxygenase (5-LO) catalyzes the first two steps in leukotriene (LT) biosynthesis. Because LTs play pivotal roles in allergy and inflammation, 5-LO represents a valuable target for anti-inflammatory drugs. Here, we investigated the molecular mechanism, the pharmacological profile, and the in vivo effectiveness of the novel 1,2-benzoquinone-featured 5-LO inhibitor RF-22c. Compound RF-22c potently inhibited 5-LO product synthesis in neutrophils and monocytes (IC50 ≥ 22 nM) and in cell-free assays (IC50 ≥ 140 nM) without affecting 12/15-LOs, cyclooxygenase (COX)-1/2, or arachidonic acid release, in a specific and reversible manner, supported by molecular docking data. Antioxidant or iron-chelating properties were not evident for RF-22c and 5-LO-regulatory cofactors like Ca2+ mobilization, ERK-1/2 activation, and 5-LO nuclear membrane translocation and interaction with 5-LO-activating protein (FLAP) were unaffected. RF-22c (0.1 mg/kg; i.p.) impaired (I) bronchoconstriction in ovalbumin-sensitized mice challenged with acetylcholine, (II) exudate formation in carrageenan-induced paw edema, and (III) zymosan-induced leukocyte infiltration in air pouches. Taken together, RF-22c is a highly selective and potent 5-LO inhibitor in intact human leukocytes with pronounced effectiveness in different models of inflammation that warrants further preclinical analysis of this agent as anti-inflammatory drug

    Assessment of the audiovestibular system in patients with rheumatoid arthritis

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    Abstract Objective This study was designed to assess hearing and vestibular function in patients with rheumatoid arthritis (RA) in comparison with a control group. In addition, we correlated these findings in disease activity and severity. Materials and methods Totally, 40 RA patients (35 women and five men) diagnosed according to the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria and 20 healthy controls (11 women and nine men), whose age ranged from 25 to 66 years with a mean age of 45.5±12.4 years, were included in the study. Each individuals was tested with pure tone audiometry. Mean values of air and bone conduction at each frequency and tympanometric values were calculated for the study groups. Videonystagmography (VNG) test including smooth pursuit, saccade, optokinetic tests, positioning tests, positional test, and water caloric tests was also carried out. Results The mean air conduction threshold values at high frequencies (4000 and 8000 Hz) in the RA group were lower than in the control group. The difference between mean air conduction threshold values of the control group and the RA group at high frequencies was statistically significant (P0.05). VNG testing revealed central abnormalities in 12 (30%) patients, peripheral abnormalities in nine (22.5%) patients, and mixed abnormalities in one (2.5%) patient. There was no association between VNG abnormalities in patients with RA and age, sex, duration of disease, accompanying vertigo complaint, and the laboratory findings (P>0.05). Conclusion There is an association between RA and audiovestibular system dysfunction regardless clinical and demographic situation of patients. We assume that the shearing and vestibular disturbances in RA are more prevalent than previously recognized. High-frequency hearing loss in RA patients could be an indicator of cochlear involvement

    Endogenous testosterone and cortisol modulate neural responses during induced anger control

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    Research with violent offenders and delinquent adolescents suggests that endogenous testosterone concentrations have the strongest positive correlations with violence among men who have low concentrations of cortisol. The present study tested the hypothesis that testosterone and cortisol would similarly interact to determine neural activation in regions supporting self-regulation in response to anger provocation. Nineteen healthy Asian male participants were insulted and asked to control their anger during functional magnetic resonance imaging (fMRI). When cortisol levels were low, testosterone positively correlated with activation in the dorsolateral prefrontal cortex (dlPFC) and thalamus, but not when cortisol levels were high. During induced anger control, functional connectivity was increased between the amygdala and a top-down prefrontal cortical control network. Moreover, the amygdala-PFC connectivity was strongest among those high in testosterone and low in cortisol. This research highlights a possible neural mechanism by which testosterone and cortisol may influence anger control
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