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.

Determination of the Wavelength Dependence of Refractive Indices of Flame Soot

Abstract: The spectral variation of the optical properties of soot particles is determined by combining classical and dynamic light scattering measurements with the Kramers-Kronig relations. Particle size and number densities are determined from scattering/extinction and autocorrelation measurements at the wavelength of 0.488 μm. This information is then combined with the spectral extinction measurements in the wavelength range 0.2 to 6.4 μm to determine the spectral variation of the refractive indices of flame soot. Results are presented for a premixed propane-oxygen flame with a fuel equivalence ratio ϕ = 1.8. The sensitivity of the technique and its advantage over the previous methods are discussed.

Implications of streamlining theory for microbial ecology

Abstract: Whether a small cell, a small genome or a minimal set of chemical reactions with self-replicating properties, simplicity is beguiling As Leonardo da Vinci reportedly said, 'simplicity is the ultimate sophistication' Two diverging views of simplicity have emerged in accounts of symbiotic and commensal bacteria and cosmopolitan free-living bacteria with small genomes The small genomes of obligate insect endosymbionts have been attributed to genetic drift caused by small effective population sizes (Ne) In contrast, streamlining theory attributes small cells and genomes to selection for efficient use of nutrients in populations where Ne is large and nutrients limit growth Regardless of the cause of genome reduction, lost coding potential eventually dictates loss of function Consequences of reductive evolution in streamlined organisms include atypical patterns of prototrophy and the absence of common regulatory systems, which have been linked to difficulty in culturing these cells Recent evidence from metagenomics suggests that streamlining is commonplace, may broadly explain the phenomenon of the uncultured microbial majority, and might also explain the highly interdependent (connected) behavior of many microbial ecosystems Streamlining theory is belied by the observation that many successful bacteria are large cells with complex genomes To fully appreciate streamlining, we must look to the life histories and adaptive strategies of cells, which impose minimum requirements for complexity that vary with niche

An ordering policy for deteriorating items with allowable shortage and permissible delay in payment

Abstract: In many inventory situations, the purchaser is allowed a permissible period to pay back the cost of goods bought without paying any interest. Depending on the length of that payment period, the purchaser can earn interest on the sales of the inventory. This paper develops a model to determine an optimal ordering policy for deteriorating items under permissible delay of payment and allowable shortage. Different facets of the permissible delays in payment are discussed, and this generalized model exhibits a set of solutions that reduces to an existing model. Results are discussed and demonstrated with an illustrative example.