Genetic studies of the leptin receptor gene in morbidly obese French Caucasian families

Family studies have shown that in some populations up to 75% of the variation of body mass index can be explained by genetic factors. However, in humans, no major obesity gene has been identified to date. In contrast, there are a number of genetically well defined animal models for obesity. In two of those models (ob/ob and db/db), defects in the same pathway are responsible for obesity. Recently, some evidence has been found for the OB gene also being involved in human obesity. In this study we investigated the potential role of the OB receptor (OBR) in the etiology of massive obesity in humans using familial linkage analyses and case-control association studies. The typing of two microsatellite markers (D1S198 and D1S209), flanking the OBR gene, in 256 sib pairs showed no evidence for linkage with obesity. In order to be able to detect small gene effects, association studies with a 3'-UTR insertion/deletion polymorphism were carried out. The results of these analyses remained non-significant (chi 2 = 3.442, P = 0.18). However, subjects heterozygous for the insertion/deletion polymorphism showed a slight trend towards lower insulin values 30 min after an oral glucose load compared to homozygous individuals (P = 0.02). In summary, our results do not support a major role of the human OBR gene in the development of morbid obesity in our population.     

Invitations for Partisan Identification: Attempts to Court Latino Voters Through Televised Latino-Oriented Political Advertisements, 1984–2000

By the year 2050, Latinos will represent the dominant ethnic minority in the United States, and researchers are just beginning to examine the campaign messages targeted to this voting bloc. This article employs identification theory to understand the rhetorical approaches used in campaign advertisements designed for these voters. Through a content analysis of campaign spots targeted to Latinos over four presidential elections (1984, 1988, 1996, 2000), we find that the invitations for party identification sent to this group tend to be positive, focus on the Latino (not the candidate), and depict Latinos as an emergent force in American politics. In trying to foster identification from this desirable voting population, it appears that campaign forces encourage Latinos to view themselves, and politics, as valuable and consequential—a marked alternative to most advertising strategies at the close of the 20th century.     

Effect of Jet Air Content on Plunge Pool Scour

The effect of air discharge on plunge pool scour was investigated by using a simplified experimental configuration. Instead of considering the complete arrangement involving chute and deflector resulting in an air-water jet impinging on a sediment surface, the mixture flow was produced with a circular pipe for which the air concentration and the jet diameter close to impact on the free water surface are known. The results of this study were primarily directed to the definition of a three-phase Froude number that accounts for the combined effects of an air-water mixture jet on scour. The analysis of data allows simple estimates of the scour geometry including a generalized scour profile, the width of scour, and the temporal advance of the extreme scour depths. It was pointed out that for a certain water velocity and selected grain characteristics, the addition of air to the jet results in an increase of scour depth. However, if the reference would be the air-water mixture velocity, scour depth decreases significantly by the addition of air to the jet.     

Undular Hydraulic Jumps in Circular Conduits

Undular hydraulic jumps in circular conduits are considered with an experimental approach. Based on previous findings in rectangular channels, this research indicates differences in terms of shape effects. All present results depend on the filling ratio of the upstream conduit flow in addition to the upstream Froude number. The results include information on the wave crests and troughs, wave lengths, and generalized axial surface profiles. The wall surface profile is shown to be similar to the axial wave profile, but with smaller wave extrema and a wave shift. The design of conduits containing undular jumps should be avoided because of unstable flow. It is also demonstrated that conduits may choke in the presence of undular jumps, with a previously established choking number relating to a design limit. For flows with choking numbers in excess of 1, choking occurs associated with a transition from the free surface to the pressurized conduit flow.     

2,3-Dimethyl-2,3-diphenylbutane mediated grafting of vinyltriethoxysilane to polyethylene: a novel radical initiation system

The melt grafting of vinyltriethoxysilane (VTEOS) to polyethylene using 2,3-dimethyl-2,3-diphenylbutane (bicumene) as a radical initiator is demonstrated and compared to conventional peroxide-initiated processes. A bicumene-initiated modification of high density polyethylene at 290 °C provided no benefits in terms of selectivity when compared to a standard peroxide-based process operating at 180 °C. However, the selectivity of linear low-density polyethylene modification was influenced by chain scission, which counteracted the molecular weight effects of macroradical combination. Reactive extrusion data as well as studies of bicumene decomposition kinetics suggest that initiation occurs through an auto-oxidation mechanism that is facilitated by the interaction of cumyl radicals with oxygen.     

Infrared spectra and composition dependence investigations of the vitreous V2O5/P2O5 system

A series of glasses in the V₂O₅-P₂O₅ system was prepared and their compositions analysed. The glass densities and molar volumes were determined. The results obtained revealed three compositional regions. In addition, the infrared absorption spectra of these glasses were measured at room temperature in the frequency range 1600–200 cm^–1. The compositional dependence of the bands present, attributed to a given band and mode of vibration, was investigated. However, the infrared data confirmed the results obtained from the density and molar volume measurements.     

The TFTR Lithium Blanket Module program

The Lithium Blanket Module (LBM) is an approximately 80×80×80 cm cubic module, representative of a helium-cooled lithium oxide fusion reactor blanket module, that will be installed on the TFTR (Tokamak Fusion Test Reactor) in late 1986. The principal objective of the LBM Program is to perform a series of neutron transport and tritium-breeding measurements throughout the LBM when it is exposed to the TFTR toroidal fusion neutron source, and to compare these data with the predictions of Monte Carlo (MCNP) neutronics codes. The LBM consists of 920 2.5-cm diameter breeder rods constructed of lithium oxide (Li₂O) pellets housed in thin-walled stainless steel tubes. Procedures for mass-producing 25,000 Li₂O pellets with satisfactory reproducibility were developed using purified Li₂O powder, and fabrication of all the breeder rods was completed in early 1985. Tritium assay methods were investigated experimentally using both small lithium metal samples and LBM-type pellets. This work demonstrated that the thermal extraction method will be satisfactory for accurate evaluation of the minute concentrations of tritium expected in the LBM pellets (0.1–1 nCi/g).     

A simplified analytic model for gain saturation and powerextraction in the flowing chemical oxygen-iodine laser

This paper describes the development of a simplified saturation model (SSM) for predicting power extraction from a chemical oxygen-iodine laser (COIL). Using the Fabry-Perot gain saturation assumption, analytic expressions for COIL extraction efficiency are presented for both constant-density and variable-density cavity conditions. The model treats mirror scattering, nonsaturable distributed losses, and diffractive losses from the mode-limiting aperture and is shown to be in excellent agreement with experimental COIL power extraction data. A comparison of the model with the Rigrod power extraction model is presented showing that the Rigrod model accurately predicts COIL extraction efficiency only in the limit that the COIL device no longer behaves as a transfer laser     

Mechanisms responsible for reduced contextual conditioning with massed unsignaled unconditional stimuli.

Massed presentation of unsignaled shock results in less conditional freezing to contextual cues than do distributed presentations. Consistent with an account of the learning deficit based on the perceptual–defensive–recuperative theory, the massed-shock deficit was attenuated by preexposure to shock or the conditioning context. This formulation was also successfully applied to the deficit in conditioning that occurs when a single shock is given immediately after placement in a context. Opponent-process theory was not supported by 2 findings: (1) the deficit was neither enhanced by shock preexposure nor reduced by an opioid antagonist, and (2) unconditional reactions were greater with massed shock. Inconsistent with the suggestion that the effect is a performance artifact specific to freezing, the massed-shock deficit was apparent for a 2nd measure of conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)