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.

Testing metabolic ecology theory for allometric scaling of tree size, growth and mortality in tropical forests

Abstract: The theory of metabolic ecology predicts specific relationships among tree stem diameter, biomass, height, growth and mortality. As demographic rates are important to estimates of carbon fluxes in forests, this theory might offer important insights into the global carbon budget, and deserves careful assessment. We assembled data from 10 oldgrowth tropical forests encompassing censuses of 367 ha and > 1.7 million trees to test the theory’s predictions. We also developed a set of alternative predictions that retained some assumptions of metabolic ecology while also considering how availability of a key limiting resource, light, changes with tree size. Our results show that there are no universal scaling relationships of growth or mortality with size among trees in tropical forests. Observed patterns were consistent with our alternative model in the one site where we had the data necessary to evaluate it, and were inconsistent with the predictions of metabolic ecology in all forests.

An investigation of the relationship between graphitization and frictional behavior of DLC coatings

Abstract: In our recent studies, diamond-like carbon (DLC) films were found to possess low coefficient of friction (f < 0.1) and excellent wear resistance. The reduction in f was found to be consistent with wear-induced graphitization of the DLC structure. The purpose of the present work was to study the effect of load and sliding velocity on the frictional behavior and graphitization process occurring in DLC during wear. Pin-on-disc experiments were conducted on DLC-coated SiC substrates at sliding velocities between 0.06 and 1.6 m s−1 under 1 and 10 N loading levels using ZrO2 balls as the pin material. Analytical transmission electron microscopy was used to characterize the structure and microstructure of the wear debris after testing. The results showed that both sliding velocity and contact load influence the graphitization process. Higher sliding velocities increase the contact frequency and the rate of temperature rise that may facilitate the release of hydrogen atoms from the sp3 structure. Higher loading enhances shear deformation and transformation of the weakened hydrogen-depleted DLC structure into graphite [10]. The present findings are consistent with our earlier proposed wear-induced graphitization mechanism for these films. An equation was developed to describe the transformation kinetics of DLC into graphite as a function of sliding velocity and applied stress.

Future employment selection methods: evaluating social networking web sites

Abstract: Purpose – The use of social networking web sites (SNWs), like Facebook and MySpace, has become extremely popular, particularly with today's emerging workforce. Employers, aware of this phenomenon, have begun to use the personal information available on SNWs to make hiring decisions. The purpose of this paper is to examine the feasibility of using applicant personal information currently available on SNWs to improve employment selection decisions.Design/methodology/approach – A total of 378 judge ratings (63 raters×6 subjects) are evaluated to determine if raters can reliably and accurately determine the big‐five personality traits, intelligence, and performance based only on information available on SNWs. Interrater reliability is assessed to determine rater consistency, followed by an assessment of rater accuracy.Findings – Based solely on viewing social networking profiles, judges are consistent in their ratings across subjects and typically able to accurately distinguish high from low performers. In ad...