Apollo water impact Status report, 1 Apr. - 1 Oct. 1969

Hydrodynamic impact simulated by impacting rigid, right circular cylinder on smooth water surface, and computer progra

Apollo water impact Status report, 1 Oct. 1969 - 1 Mar. 1970

Computer program for Apollo water landin

Hydrodynamic water impact

The hydrodynamic impact of a falling body upon a viscous incompressible fluid was investigated by numerically solving the equations of motion. Initially the mathematical model simulated the axisymmetric impact of a rigid right circular cylinder upon the initially quiescent free surface of a fluid. A compressible air layer exists between the falling cylinder and the liquid free surface. The mathematical model was developed by applying the Navier-Stokes equations to the incompressible air layer and the incompressible fluid. Assuming the flow to be one dimensional within the air layer, the average velocity, pressure and density distributions were calculated. The liquid free surface was allowed to deform as the air pressure acting on it increases. For the liquid the normalized equations were expressed in two-dimensional cylindrical coordinates. The governing equations for the air layer and the liquid were expressed in finite difference form and solved numerically. For the liquid a modified version of the Marker-and-Cell method was used. The mathematical model has been reexamined and a new approach has recently been initiated. Essentially this consists of examining the impact of an inclined plate onto a quiesent water surface with the equations now formulated in cartesian coordinates

Improvement of propeller static thrust estimation Status report, 1 Nov. 1968 - 31 Aug. 1969

Aerodynamic load effects on propeller blade desig

Improvement of propeller static thrust estimation

The problem of improving the performance estimation of propellers operating in the heavily loaded static thrust condition was studied. The Goldstein theory was assessed as it applies to propellers operating in the static thrust. A review of theoretical considerations is presented along with a summary of the attempts made to obtain a numerical solution. The chordwise pressure distribution was determined during operation at a tip speed of 500 ft/sec. Chordwise integration of the pressures leads to the spanwise load distribution and further integration would give the axial thrust

Tests on propellers under static thrust conditions

Dynamometer tests of propellers under static thrust condition

Desiccant Cooling Systems - A Review

Desiccant cooling systems have been investigated extensively during the past decade as alternatives to electrically driven vapor compression systems because regeneration temperatures of the desiccant - about 160°F, can be achieved using natural gas or by solar systems. Comfort is achieved by reducing the moisture content of air by a solid or liquid desiccant and then reducing the temperature in an evaporative cooler (direct or indirect). Another system is one where the dehumidifier removes enough moisture to meet the latent portion of the load while the sensible portion is met by a vapor compression cooling system; desiccant regeneration is achieved by using the heat rejected from the condenser together with other thermal sources. At present, residential desiccant cooling systems are in actual operation but are more costly than vapor compression systems, resulting in relatively long payback periods. Component efficiencies need to be improved, particularly the efficiency of the dehumidifier

Desiccant Cooling Systems - A Review

Desiccant cooling systems have been investigated extensively during the past decade as alternatives to electrically driven vapor compression systems because regeneration temperatures of the desiccant - about 160°F, can be achieved using natural gas or by solar systems. Comfort is achieved by reducing the moisture content of air by a solid or liquid desiccant and then reducing the temperature in an evaporative cooler (direct or indirect). Another system is one where the dehumidifier removes enough moisture to meet the latent portion of the load while the sensible portion is met by a vapor compression cooling system; desiccant regeneration is achieved by using the heat rejected from the condenser together with other thermal sources. At present, residential desiccant cooling systems are in actual operation but are more costly than vapor compression systems, resulting in relatively long payback periods. Component efficiencies need to be improved, particularly the efficiency of the dehumidifier

RSPO3 impacts body fat distribution and regulates adipose cell biology in vitro

Fat distribution is an independent cardiometabolic risk factor. However, its molecular and cellular underpinnings remain obscure. Here we demonstrate that two independent GWAS signals at RSPO3, which are associated with increased body mass index-adjusted waist-to-hip ratio, act to specifically increase RSPO3 expression in subcutaneous adipocytes. These variants are also associated with reduced lower-body fat, enlarged gluteal adipocytes and insulin resistance. Based on human cellular studies RSPO3 may limit gluteofemoral adipose tissue (AT) expansion by suppressing adipogenesis and increasing gluteal adipocyte susceptibility to apoptosis. RSPO3 may also promote upper-body fat distribution by stimulating abdominal adipose progenitor (AP) proliferation. The distinct biological responses elicited by RSPO3 in abdominal versus gluteal APs in vitro are associated with differential changes in WNT signalling. Zebrafish carrying a nonsense rspo3 mutation display altered fat distribution. Our study identifies RSPO3 as an important determinant of peripheral AT storage capacity

The spotted gar genome illuminates vertebrate evolution and facilitates human-teleost comparisons

To connect human biology to fish biomedical models, we sequenced the genome of spotted gar (Lepisosteus oculatus), whose lineage diverged from teleosts before teleost genome duplication (TGD). The slowly evolving gar genome has conserved in content and size many entire chromosomes from bony vertebrate ancestors. Gar bridges teleosts to tetrapods by illuminating the evolution of immunity, mineralization and development (mediated, for example, by Hox, ParaHox and microRNA genes). Numerous conserved noncoding elements (CNEs; often cis regulatory) undetectable in direct human-teleost comparisons become apparent using gar: functional studies uncovered conserved roles for such cryptic CNEs, facilitating annotation of sequences identified in human genome-wide association studies. Transcriptomic analyses showed that the sums of expression domains and expression levels for duplicated teleost genes often approximate the patterns and levels of expression for gar genes, consistent with subfunctionalization. The gar genome provides a resource for understanding evolution after genome duplication, the origin of vertebrate genomes and the function of human regulatory sequences