Louisiana State University

About: Louisiana State University is a education organization based out in Baton Rouge, Louisiana, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 40206 authors who have published 76587 publications receiving 2566076 citations. The organization is also known as: LSU & Louisiana State University and Agricultural and Mechanical College.

Correlation of the highest-energy cosmic rays with nearby extragalactic objects.

Abstract: Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrate that there is a correlation between the arrival directions of cosmic rays with energy above {approx} 6 x 10{sup 19} eV and the positions of active galactic nuclei (AGN) lying within {approx} 75 Mpc. We reject the hypothesis of an isotropic distribution of these cosmic rays at over 99% confidence level from a prescribed a priori test. The correlation we observe is compatible with the hypothesis that the highest energy particles originate from nearby extragalactic sources whose flux has not been significantly reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources.

Exploring the Sensitivity of Next Generation Gravitational Wave Detectors

Abstract: The second-generation of gravitational-wave detectors are just starting operation, and have already yielding their first detections. Research is now concentrated on how to maximize the scientific potential of gravitational-wave astronomy. To support this effort, we present here design targets for a new generation of detectors, which will be capable of observing compact binary sources with high signal-to-noise ratio throughout the Universe.

Fast-food consumption among US adults and children: Dietary and nutrient intake profile

Abstract: Objective To examine the dietary profile associated with fast-food use. To compare the dietary intake of individuals on the day that they ate fast food with the day that fast food was not eaten. Design Cross-sectional study design. The dietary intake of individuals who reported eating fast food on one or both survey days was compared with those who did not report eating fast food. Among the individuals who reported eating fast food, dietary intake on the day when fast food was eaten was compared with the day when fast food was not eaten. Weighted comparison of mean intakes and pairwise t-test were used in the statistical analysis. Subjects/setting Data from 17,370 adults and children who participated in the 1994-1996 and 1998 Continuing Survey of Food Intakes by Individuals. Dietary intake data were collected by 2 non-consecutive 24-hour dietary recalls. Results Fast-food use was reported by 37% of the adults and 42% of the children. Adults and children who reported eating fast food had higher intake of energy, fat, saturated fat, sodium, carbonated soft drink, and lower intake of vitamins A and C, milk, fruits and vegetables than those who did not reported eating fast food ( P Conclusions Consumers should be aware that consumption of high-fat fast food may contribute to higher energy and fat intake, and lower intake of healthful nutrients.

Evolution and progression of atherosclerotic lesions in coronary arteries of children and young adults.

Abstract: In an autopsy study of the evolution of atherosclerotic lesions in young people, we obtained the coronary arteries and aortas of 1160 male and female subjects who died between full-term birth and age 29 years. In this article, we report the light and electron microscopic observations of the coronary arteries of 565 of these subjects in which we fixed the coronary arteries by perfusion with glutaraldehyde under pressure. From birth, the intima was always thicker in the half of the coronary artery circumference opposite the flow-divider wall of a bifurcation (eccentric thickening). In cases where we found lipid in the intima, there was always more in eccentric thickening. Isolated macrophage foam cells in the intima of infants were the earliest sign of lipid retention. These cells occurred in 45% of infants in the first 8 months of life but decreased subsequently. At puberty, more substantial accumulations of macrophage foam cells reappeared in more children. Foam cells were now accompanied by lipid droplets in existing smooth muscle cells and by thinly scattered extracellular lipid. Sixty-five percent of children between ages 12 and 14 years had such lesions. An additional 8% of children had progressed beyond this early stage and had developed advanced preatheroma or atheroma stages. Such advanced lesions, located only in areas of eccentric thickening, were characterized by the addition of massive extracellular lipid that displaced normal cells and matrix and, thus, damaged and weakened the arterial wall.(ABSTRACT TRUNCATED AT 250 WORDS)

Water escape structures in coarse-grained sediments

Abstract: Three processes of water escape characterize the consolidation of silt-, sand-and gravel-sized sediments. Seepage involves the slow upward movement of pore fluids within existing voids or rapid flow within compact and confined sediments. Liquefaction is marked by the sudden breakdown of a metastable, loosely packed grain framework, the grains becoming temporarily suspended in the pore fluid and settling rapidly through the fluid until a grain-supported structure is re-established. Fluidization occurs when the drag exerted by moving pore fluids exceeds the effective weight of the grains; the particles are lifted, the grain framework destroyed, and the sediment strength reduced to nearly zero. Diagenetic sedimentary structures formed in direct response to processes of fluid escape are here termed water escape structures. Four main types of water escape structures form during the fluidization and liquefaction of sands: (1) soft-sediment mixing bodies, (2) soft-sedimsnt intrusions, (3) consolidation laminations, and (4) soft-sediment folds. These structures represent both the direct rearrangement of sediment grains by escaping fluids and the deformation of hydroplastic, liquefied, or fluidized sediment in response to external stresses. Fundamental controls on sediment consolidation are exerted by the bulk sediment properties of grain size, packing, permeability, and strength, which together determine whether consolidation will occur and, if so the course it follows, and by external disturbances which act to trigger liquefaction and fluidization. The liquefaction and fluidization of natural sands usually accompanies the collapse of loosely packed cross-bedded deposits. This collapse is commonly initiated by water forced into the units as underlying beds, especially muds and clays, consolidate. The consolidation of subjacent units is often triggered by the rapid deposition of the sand itself, although earthquakes or other disturbances are probably influential in some instances. Water escape structures most commonly form in fine- to medium-grained sands deposited at high instantaneous and mean sedimentation rates; they are particularly abundant in cross-laminated deposits but rare in units deposited under upper flow regime plane bed conditions. Their development is favoured by upward decreasing permeability within sedimentation units such as normally graded turbidites. They are especially common in sequences made up of alternating fine-(clay and mud) and coarse-grained (sand) units such as deep-sea flysch prodelta, and, to a lesser extent, fluvial point bar, levee, and proximal overbank deposits.