State of gas exchange in recumbent and orthostatic positions and under physical load in healthy persons of varying age, sex and body build

Age effect on gas exchange was studied in the recumbent and orthostatic positions and under physical load. In the case of the older age group and for normal as compared with hypersthenic persons, oxygen consumption during rest and during moderate physical overload diminishes. When the vertical position is assumed oxygen consumption in persons of various age groups is distinctly increased, particularly in the elderly group. There is a reduction in the amount of oxygen consumption, oxygen pulse, recovery coefficient, and work efficiency under moderate overload. In persons over 50, physical labor induces a large oxygen requirement and a sharp rise in the level of lactic acid and the blood's lactate/pyruvate ratio. No distinct difference was noted in the amount of oxygen consumed during rest and during physical overload in men and women of the same physical development and age

Analysis of structure-phase states in-a-bulk hardened and a head-hardened rails

A layer-by-layer analysis along the central axis and over the fillet of rails for low-temperature service, rails with enhanced wear resistance and contact fatigue resistance, and for senior-grade rails, bulk oil hardened and DT 350 rails head-hardened under different conditions has been carried out by modern material science methods. Quantitative variables have been established and a comparison of structure-phase states, defective substructure and internal stress fields has been made

Microstructure and crystallographic texture of silicon iron modified by torsion under quasihydrostatic pressure

The electron backscatter diffraction, X-ray diffraction analysis, electromotive force instantaneous measurement, microhardness and coercive force measurement techniques are used to explore the development of the microstructure, crystallographic texture and physico-mechanical properties of silicon iron (Fe-3% Si) alloy under quasi-hydrostatic pressure in a Bridgman anvil. It is found that the alloy deformation is accompanied by its significant hardenin

Virtual Shaping on NACA 0015 by Means of a High Momentum Coefficient Synthetic Jet

Results concerning flow control on a NACA 0015 airfoil using high power synthetic jets are presented for low incidences and for Reynolds numbers ranging from 132000 to 425000. The forcing was operated through a spanwise slit positioned near the leading edge at x/c=1.25% or at x/c=10% on the upper surface. Static pressure distribution measurements around the airfoil, wake surveys and smoke flow visualizations were performed. Pressure distributions were significantly modified around the injection location, showing an area of intense suction which increased the lift and strongly affected the drag. Flow visualizations highlighted that the intense suction was due to a virtual shaping effect caused by the formation of a recirculation bubble capable of displacing the streamlines. Low momentum deficits in the wake velocity distributions and, in certain conditions, jet-like flow was observed for the forced cases. Finally, a scaling law relating the bubble size to the forcing intensity is propose

Deformation behavior of high-mn TWIP steels processed by warm-to-hot working

The deformation behavior of 18%Mn TWIP steels (upon tensile tests) subjected to warm-to-hot rolling was analyzed in terms of Ludwigson-type relationship, i.e., a = K\ e”1 + exp(K - ”2 e). Parameters of Ki and ” depend on material and processing conditions and can be expressed by unique functions of inverse temperatur

The Sunyaev-Zel'dovich Infrared Experiment: A Millimeter-wave Receiver for Cluster Cosmology

Measurements of the Sunyaev-Zel'dovich (S-Z) effect towards distant clusters of galaxies can be used to determine the Hubble constant and the radial component of cluster peculiar velocities. Determination of the cluster peculiar velocity requires the separation of the two components of the S-Z effect, which are due to the thermal and bulk velocities of the intracluster plasma. The two components can be separated practically only at millimeter (mm) wavelengths. Measurements of the S-Z effect at mm wavelengths are subject to minimal astrophysical confusion and, therefore, provide an important test of results obtained at longer wavelengths. We describe the instrument used to make the first significant detections of the S-Z effect at millimeter wavelengths. This instrument employs new filter, detector, and readout technologies to produce sensitive measurements of differential sky brightness stable on long time scales. These advances allow drift scan observations which achieve high sensitivity while minimizing common sources of systematic error.Comment: 19 pages, 15 postscript figures, LaTeX(aaspptwo.sty), ApJ(in press

Optimal measurement of visual motion across spatial and temporal scales

Sensory systems use limited resources to mediate the perception of a great variety of objects and events. Here a normative framework is presented for exploring how the problem of efficient allocation of resources can be solved in visual perception. Starting with a basic property of every measurement, captured by Gabor's uncertainty relation about the location and frequency content of signals, prescriptions are developed for optimal allocation of sensors for reliable perception of visual motion. This study reveals that a large-scale characteristic of human vision (the spatiotemporal contrast sensitivity function) is similar to the optimal prescription, and it suggests that some previously puzzling phenomena of visual sensitivity, adaptation, and perceptual organization have simple principled explanations.Comment: 28 pages, 10 figures, 2 appendices; in press in Favorskaya MN and Jain LC (Eds), Computer Vision in Advanced Control Systems using Conventional and Intelligent Paradigms, Intelligent Systems Reference Library, Springer-Verlag, Berli

Measurement of the Hubble Constant from X-ray and 2.1 mm Observations of Abell 2163

We report 2.1 mm observations of the Sunyaev-Zel'dovich (S-Z) effect; these observations confirm our previous detection of a decrement in the Cosmic Microwave Background intensity towards the cluster Abell 2163. The S-Z data are analyzed using the relativistically correct expression for the Comptonization. We begin by assuming the intracluster (IC) gas to be isothermal at the emission weighted average temperature determined by a combined analysis of the ASCA and GINGA X-ray satellite observations. Combining the X-ray and S-Z measurements, we determine the Hubble constant to be H_0(q_0=0.5)= 60 +40/-23 km/s/Mpc, where the uncertainty is dominated by the systematic difference in the ASCA and GINGA determined IC gas temperatures. ASCA observations suggest the presence of a significant thermal gradient in the IC gas. We determine $H_0$ as a function of the assumed IC gas thermal structure. Using the ASCA determined thermal structure and keeping the emission weighted average temperature the same as in the isothermal case, we find H_0(q_0=0.5)= 78 +54/-28 km/s/Mpc. Including additional uncertainties due to cluster asphericity, peculiar velocity, IC gas clumping, and astrophysical confusion, we find H_0(q_0=0.5)= 78 +60/-40 km/s/Mpc.Comment: 24 pages, 10 postscript figures, LaTeX(aaspptwo.sty), ApJ(in press