3,819 research outputs found
Approach path control for powered-lift STOL aircraft
A flight control system concept is defined for approach flightpath control of an augmentor wing (or similar) powered-lift STOL configuration. The proposed STOL control concept produces aircraft transient and steady-state control responses that are familiar to pilots of conventional jet transports, and has potential for good handling qualities ratings in all approach and landing phases. The effects of trailing-edge rate limits, real-engine dynamics, and atmospheric turbulence are considered in the study. A general discussion of STOL handling qualities problems and piloting techniques is included
An approach for configuring space photovoltaic tandem arrays based on cell layer performance
Meeting solar array performance goals of 300 W/Kg requires use of solar cells with orbital efficiencies greater than 20 percent. Only multijunction cells and cell layers operating in tandem produce this required efficiency. An approach for defining solar array design concepts that use tandem cell layers involve the following: transforming cell layer performance at standard test conditions to on-orbit performance; optimizing circuit configuration with tandem cell layers; evaluating circuit sensitivity to cell current mismatch; developing array electrical design around selected circuit; and predicting array orbital performance including seasonal variations
Development of weight and cost estimates for lifting surfaces with active controls
Equations and methodology were developed for estimating the weight and cost incrementals due to active controls added to the wing and horizontal tail of a subsonic transport airplane. The methods are sufficiently generalized to be suitable for preliminary design. Supporting methodology and input specifications for the weight and cost equations are provided. The weight and cost equations are structured to be flexible in terms of the active control technology (ACT) flight control system specification. In order to present a self-contained package, methodology is also presented for generating ACT flight control system characteristics for the weight and cost equations. Use of the methodology is illustrated
PROTECTIVE EFFECT OF SYNTHETIC ANTIOXIDANTS AND ETHANOLIC EXTRACT OF BACOPA MONNIERI AGAINST LEAD TOXICITY INDUCED METABOLIC DYSFUNCTIONS IN MICE BRAIN AND LIVER HOMOGENATES: AN IN VITRO APPROACH
Objective: The main objective of the present study was to investigate the ameliorative potential of synthetic antioxidants mixture comprising N-acetyl cysteine, ascorbic acid, tocopheryl acetate, and thiamine as micronutrient combinational therapy and ethanolic extract of Bacopa monnieri as herbal antioxidant therapy approach against lead toxicity-induced metabolic dysfunctions in vitro.
Methods: Experimental study involved in vitro exposure of mice brain and liver homogenates to different doses (100 μM, 250 μM, and 500 μM) of lead acetate. The study also involved coadministration of high-dose lead acetate (500 μM) and specific dosage of synthetic antioxidants or ethanolic extract of B. monnieri separately to homogenate cultures. Alterations in metabolic parameters of protein levels and lipid peroxidation were analyzed for evaluating the protective effect of synthetic antioxidants and B. monnieri against lead intoxication.
Results: Results revealed dose-dependent statistically significant (p<0.001) reduction in protein levels and elevation in lipid peroxidation in lead acetate exposed mice brain and liver homogenates as compared to their respective control groups. Coadministration of lead acetate and synthetic antioxidants mixture or B. monnieri in the brain and liver homogenates conferred protection and manifested maintenance of studied biochemical parameters nearest to control groups. Ameliorative efficacy of B. monnieri against lead-induced neurotoxicity and hepatotoxicity was found to be more pronounced than that of a mixture of synthetic antioxidants.
Conclusion: Synthetic antioxidants mixture (N-acetyl cysteine, ascorbic acid, tocopheryl acetate, and thiamine) and B. monnieri exhibited remarkable therapeutic efficacy against lead toxicity-induced metabolic dysfunctions in mice brain and liver homogenates by virtue of their antioxidant, neuroprotective, and hepatoprotective abilities
AMELIORATIVE ACTION OF SYNTHETIC AND HERBAL ANTIOXIDANTS ON LEAD INDUCED HEPATOTOXICITY: AN IN VITRO STUDY
ABSTRACTObjective: A lead is one of the most hazardous and persistent environmental toxicants of global concern today. The lead has propensity to act as apotent mammalian systemic toxicant. Therefore, investigation of effective ameliorative techniques against lead toxicity through proper exploration ofmolecular mechanisms is the main objective of the current study.Methods: Present in vitro study deals with the investigation of ameliorative effect of specific synthetic antioxidants in a mixture especially,N-acetyl cysteine (5.5 mM/kg/day), ascorbic acid (200 mg/kg/day), tocopheryl acetate (160 mg/kg/day), and thiamine (30 mg/kg/day) as novelcombinational therapy approach as well as Bacopa monnieri (10 mg/kg/day) as herbal antioxidant therapy against lead induced hepatotoxicity.The current synergistic study involves culturing of goat liver in Dulbecco's Modified Eagle Medium:F12 (1:1 mixture) culture media containing1 ppm lead acetate along with co-administration of selective antioxidants at prescribed dosage for 6 hrs. Selective biochemical parameters suchas lipid peroxidation (LPO), protein levels, alkaline phosphatase (ALPase), acid phosphatase (ACPase), succinate dehydrogenase (SDH), adenosinetriphosphatase (ATPase), and superoxide dismutase (SOD) activities were analyzed and observed for protection against lead intoxication.Results: Results indicate significant alterations in all biochemical parameters studied in lead exposed cultures as compared to control. Total andsoluble proteins, ALPase, SDH, and ATPase showed significant reduction while LPO, ACPase, and SOD activities increased significantly in lead exposedcultures as compared to control. The results also emphasized that simultaneous administration of prescribed antioxidants and lead in culturesmanifested maintenance of all biochemical parameters studied nearest to control group.Conclusion: Synthetic and herbal antioxidants therapy have protective role against lead induced hepatotoxicity.Keywords: Lead toxicity, Synthetic antioxidants, Herbal antioxidant, Bacopa monnieri extract, Hepatotoxicity, Oxidative stress, Plumbism,Hepatoprotective activity, Lipid peroxidation, Superoxide dismutase
Masticatory biomechanics in the rabbit : a multi-body dynamics analysis
Acknowledgement We thank Sue Taft (University of Hull) for the µCT-scanning of the rabbit specimen used in this study. We also thank Raphaël Cornette, Jacques Bonnin, Laurent Dufresne, and l'Amicale des Chasseurs Trappistes (ACT) for providing permission and helping us capture the rabbits used for the in vivo bite force measurements at la Réserve Naturelle Nationale de St Quentin en Yvelines, France.Peer reviewedPublisher PD
Food preservation I
June, 1954."University of Missouri College of Agriculture and the United States Department of Agriculture Cooperating"--Page [14].Title from caption
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