7,106 research outputs found
In Pursuit of Sex Parity: Are Girls Becoming more Educated than Boys?
One of the Millennium Development Goals (MDGs) is the elimination of gender disparity in primary and secondary education. Global initiatives toward this end have mostly been to bring the benefits of education closer to girls so that the gap between them and boys may eventually close. In the Philippines, however, mounting evidence points to a reversed direction of the gender disparity. Are our boys falling behind on education? Why? Read more.education, millennium development goal (MDG), education indicators, Education for All (EFA), sex parity
QUANTITATIVE EFFECTS OF NUTRITIONAL ESSENTIAL AMINO ACID DEFICIENCY UPON IMMUNE RESPONSES TO TUMORS IN MICE
Mice were fed diets deficient in a single essential amino acid, and the primary immune responses to inoculation of allogenic tumor cells was measured by in vitro assay of cellular immunity. Moderate reduction of the amino acids phenylalanine-tyrosine, valine, threonine, methionine-cystine, isoleucine, and tryptophane in the diet produced profound depression of hemagglutinating and blocking antibody responses, although cytotoxic cell-mediated immunity remained intact. These diets had previously been shown to result in a selective depression of tumor growth in mice. Limitation of the amino acids arginine, histidine, and lysine in the diets gave rise to only slight depression of the immune responses. These diets had previously been shown to produce a proportional decrease in both tumor growth and host body weight. Moderate leucine restriction resulted in a paradoxical depression of cytotoxic cell-mediated immunity with little effect on serum blocking activity. Slight increases had previously been noted in the weight of tumors in mice fed leucine-restricted diets. Deficiency or imbalance of essential amino acids in the diet may produce profound depression of immune responses and apparent, marked changes in the immune resistance of the host animal to tumors
Molecular Carbon Chains and Rings in TMC-1
We present mapping results in several rotational transitions of HC3N, C6H,
both cyclic and linear C3H2 and C3H, towards the cyanopolyyne peak of the
filamentary dense cloud TMC-1 using the IRAM 30m and MPIfR 100m telescopes. The
spatial distribution of the cumulene carbon chain propadienylidene H2C3
(hereafter l-C3H2) is found to deviate significantly from the distributions of
the cyclic isomer c-C3H2, HC3N, and C6H which in turn look very similar. The
cyclic over linear abundance ratio of C3H2 increases by a factor of 3 across
the filament, with a value of 28 at the cyanopolyyne peak. This abundance ratio
is an order of magnitude larger than the range (3 to 5) we observed in the
diffuse interstellar medium. The cyclic over linear abundance ratio of C3H also
varies by ~2.5 in TMC-1, reaching a maximum value (13) close to the
cyanopolyyne peak. These behaviors might be related to competitive processes
between ion-neutral and neutral-neutral reactions for cyclic and linear
species.Comment: Accepted for publication in The Astrophysical Journal, part I. 24
pages, including 4 tables, 7 figures, and figure caption
Transonic shock-induced dynamics of a flexible wing with a thick circular-arc airfoil
Transonic shock boundary layer oscillations occur on rigid models over a small range of Mach numbers on thick circular-arc airfoils. Extensive tests and analyses of this phenomena have been made in the past but essentially all of them were for rigid models. A simple flexible wing model with an 18 pct. circular arc airfoil was constructed and tested in the Langley Transonic Dynamics Tunnel to study the dynamic characteristics that a wing might have under these circumstances. In the region of shock boundary layer oscillations, buffeting of the first bending mode was obtained. This mode was well separated in frequency from the shock boundary layer oscillations. A limit cycle oscillation was also measured in a third bending like mode, involving wind vertical bending and splitter plate motion, which was in the frequency range of the shock boundary layer oscillations. Several model configurations were tested, and a few potential fixes were investigated
Experimental flutter boundaries with unsteady pressure distributions for the NACA 0012 Benchmark Model
The Structural Dynamics Div. at NASA-Langley has started a wind tunnel activity referred to as the Benchmark Models Program. The objective is to acquire test data that will be useful for developing and evaluating aeroelastic type Computational Fluid Dynamics codes currently in use or under development. The progress is described which was achieved in testing the first model in the Benchmark Models Program. Experimental flutter boundaries are presented for a rigid semispan model (NACA 0012 airfoil section) mounted on a flexible mount system. Also, steady and unsteady pressure measurements taken at the flutter condition are presented. The pressure data were acquired over the entire model chord located at the 60 pct. span station
What We Did Last Summer: Depicting DES Data to Enhance Simulation Utility and Use
At Kennedy Space Center (KSC), an important use of Discrete Event Simulation (DES) addresses ground operations .of missions to space. DES allows managers, scientists and engineers to assess the number of missions KSC can complete on a given schedule within different facilities, the effects of various configurations of resources and detect possible problems or unwanted situations. For fifteen years, DES has supported KSC efficiency, cost savings and improved safety and performance. The dense and abstract DES data, however, proves difficult to comprehend and, NASA managers realized, is subject to misinterpretation, misunderstanding and even, misuse. In summer 2008, KSC developed and implemented a NASA Exploration Systems Mission Directorate (ESMD) project based on the premise that visualization could enhance NASA's understanding and use of DES
Binding Site and Affinity Prediction of General Anesthetics to Protein Targets Using Docking
BACKGROUND: The protein targets for general anesthetics remain unclear. A tool to predict anesthetic binding for potential binding targets is needed. In this study, we explored whether a computational method, AutoDock, could serve as such a tool. METHODS: High-resolution crystal data of water-soluble proteins (cytochrome C, apoferritin, and human serum albumin), and a membrane protein (a pentameric ligand-gated ion channel from Gloeobacter violaceus [GLIC]) were used. Isothermal titration calorimetry (ITC) experiments were performed to determine anesthetic affinity in solution conditions for apoferritin. Docking calculations were performed using DockingServer with the Lamarckian genetic algorithm and the Solis and Wets local search method (http://www.dockingserver.com/web). Twenty general anesthetics were docked into apoferritin. The predicted binding constants were compared with those obtained from ITC experiments for potential correlations. In the case of apoferritin, details of the binding site and their interactions were compared with recent cocrystallization data. Docking calculations for 6 general anesthetics currently used in clinical settings (isoflurane, sevoflurane, desflurane, halothane, propofol, and etomidate) with known 50% effective concentration (EC50) values were also performed in all tested proteins. The binding constants derived from docking experiments were compared with known EC50 values and octanol/water partition coefficients for the 6 general anesthetics. RESULTS: All 20 general anesthetics docked unambiguously into the anesthetic binding site identified in the crystal structure of apoferritin. The binding constants for 20 anesthetics obtained from the docking calculations correlate significantly with those obtained from ITC experiments (P = 0.04). In the case of GLIC, the identified anesthetic binding sites in the crystal structure are among the docking predicted binding sites, but not the top ranked site. Docking calculations suggest a most probable binding site located in the extracellular domain of GLIC. The predicted affinities correlated significantly with the known EC50 values for the 6 frequently used anesthetics in GLIC for the site identified in the experimental crystal data (P = 0.006). However, predicted affinities in apoferritin, human serum albumin, and cytochrome C did not correlate with these 6 anesthetics\u27 known experimental EC50values. A weak correlation between the predicted affinities and the octanol/water partition coefficients was observed for the sites in GLIC. CONCLUSION: We demonstrated that anesthetic binding sites and relative affinities can be predicted using docking calculations in an automatic docking server (AutoDock) for both water-soluble and membrane proteins. Correlation of predicted affinity and EC50 for 6 frequently used general anesthetics was only observed in GLIC, a member of a protein family relevant to anesthetic mechanism
Effectiveness of Mechanical Horse-Riding Simulators on Postural Balance in Neurological Rehabilitation: Systematic Review and Meta-Analysis
Mechanical horse-riding simulators consist of a device that mimics the movement of a real horse, generating between 50 and 100 three-dimensional physical movements (forward and back, left and right, up and down). The main objective of this study is to analyze the effectiveness of mechanical horse-riding simulators to improve postural balance in subjects with neurological disorders. The search was conducted during January-March 2019 in PubMed, Physiotherapy Evidence Database (PEDro), Cochrane, Web of Science, CINAHL, and Scopus. The methodological quality of the studies was evaluated through the PEDro scale. A total of seven articles were included in this systematic review, of which four contributed information to the meta-analysis. Statistical analysis showed favorable results for balance in stroke patients, measured by the Berg Balance Scale (standardized mean difference (SMD) = 3.24; 95%; confidence interval (CI): 1.66-4.83). Not conclusive results were found in sitting postural balance, measured using the Gross Motor Function Measure-66 (GMFM-66) Sitting Dimension, in patients with cerebral palsy. Most studies have shown beneficial effects on postural balance compared with conventional physical therapy. However, due to the limited number of articles and their low methodological quality, no solid conclusions can be drawn about the effectiveness of this therapy
Integrating Multi-agent System and Microsimulation for Dynamic Modeling of Urban Freight Transport
This work aims to apply an integration between a multi-agent system and microsimulation to take advantage of the large amount of data generated in urban freight transport to improve the overall performance of the urban supply chain without forgetting the principles of autonomy that govern each of its actors, responding to the different dynamic scenarios that may arise in the operational context. The integration framework produces a satisfactory communication process in those modeling methods measured by two indexes: throughput and latency. The results of this integration show a robust response to dynamic scenarios and allow reacting to the different quantity of changes without dismissing the search for optimum solutions
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