Collection of CERES Results

Plenary talk in Quark Matter 2005, Budapest

Recovery from Exercise: The Influences of Supplementation and Rest Interval

Recovery from exercise is immensely important and under studied. The experiments conducted throughout this research have focused on testing the effects of rest interval during resistance exercise and the efficacy of acetic acid feeding on recovery rate. To elucidate the relationship between rest interval and recovery energy expenditure two experiments were undertaken. These experiments were designed to alter only rest interval while maintaining work intensity and volume. No difference in the total energy expenditure during the short phase of recovery (first hour) was found, but energy expenditure during the prolonged phase (days post exercise) was minorly increased by lowering rest interval. These results combined with the metabolic and affective data collected have raised questions as to the underlying mechanisms which warrant further study. The third and fourth experiment focused on acetic acid consumption and recovery from exhaustive exercise. Previous studies in animal models have shown significantly improved recovery rates. This research was focused on testing the efficacy of acetic acid feeding in humans to improve performance. Participants therefore exercised, were given a time to rest, and a recovery beverage was consumed. After recovery participant’s ability to perform was assessed, and various metabolic measurements were assessed. The findings of these projects are promising, as acetic acid appears to have positive effects on recovery. The potential benefits to millions of athletes in a variety of sports are immense. The work completed throughout this Dissertation has successfully added to the field of recovery research, and provided more questions to be answered in the future

Open charm contribution to dilepton spectra produced in nuclear collisions at SPS energies

Measurements of open charm hadro-production from CERN and Fermilab experiments are reviewed, with particular emphasis on the absolute cross sections and on their A and sqrt(s) dependences. Differential pt and xf cross sections calculated with the Pythia event generator are found to be in reasonable agreement with recent data. The calculations are scaled to nucleus-nucleus collisions and the expected lepton pair yield is deduced. The charm contribution to the low mass dilepton continuum observed by the CERES experiment is found to be negligible. In particular, it is shown that the observed low mass dilepton excess in S-Au collisions cannot be explained by charm enhancement.Comment: 19 pages, 12 eps figures included. To be published in Z.Phys.

Studies of water diffusion in the vicinity of single-supported lipid membranes

"May 2014."Thesis Supervisor: Dr. Haskell Taub.Includes vita.The insertion and function of membrane-embedded proteins is one of the most fundamental challenges facing biological physics today. At its core, addressing these phenomena requires an understanding of the interaction of proteins with the lipid bilayer and its associated water molecules. As such, the study of water dynamics and structure near model lipid bilayers can provide foundational knowledge upon which more detailed understanding of these core issues may be developed. Previous quasielastic neutron scattering measurements on lipid membranes have used samples of large stacks of membranes with an unknown amount of water between layers. This geometry complicates interpretation and renders comparison to molecular dynamics simulations difficult. Instead, this work investigates water dynamics on single-supported bilayers of the model charge-neutral lipid DMPC (dimyristoyl-sn-glycero-3-phosphocholine) and its anionic analogue DMPG (dimyristoyl-sn-glycero- 3-phosphoglycerol). Single bilayers can be more directly compared to molecular dynamics simulations, can be interrogated with Atomic Force Microscopy, and avoid the uncertainty in quantifying the amount of water in samples. A new method for producing the anionic bilayers is developed, which is a variant of the vesicle fusion method. Atomic Force Microscopy is used to characterize the quality of both DMPC and DMPG membranes supported on SiO?��-coated silicon substrates. Measuring the bilayer thickness as a function of temperature reveals that the gel-to-fluid phase transition is found to be shifted to significantly higher temperatures for adsorbed lipid bilayers in air compared to free vesicles in solution. The temperature-dependent quasielastic spectra from hydrated DMPC bilayers reveal three types of membrane-associated water. First, a large amount of water diffuses similarly to bulk supercooled water and freezes at 265 K. Second, a smaller amount of water closer to the membrane diffuses more slowly than bulk supercooled water at the same temperature and freeIncludes bibliographical references (pages 144-151)

Pion-pion and pion-proton correlations: New results from CERES

Results of a new two-particle correlation analysis of central Pb+Au collision data at 158 GeV per nucleon are presented. The emphasis is put on pion-proton correlations and on the dependence of the two-pion correlation radii on the azimuthal emission angle with respect to the reaction plane.Results of a new two-particle correlation analysis of central Pb+Au collision data at 158 GeV per nucleon are presented. The emphasis is put on pion-proton correlations and on the dependence of the two-pion correlation radii on the azimuthal emission angle with respect to the reaction plane

The acute effects of stretching on pennation angle and force production

PURPOSE: This study was designed to investigate the acute effects of stretching on pennation angle of the Medial Gastrocnemius and maximal voluntary isotonic plantar flexion. METHODS: 24 healthy college age subjects (14 female, 10 male, age 19-30) completed four trials using a randomized crossover design. Trials consisted of assessing the maximal voluntary isotonic contraction (MVC) and pennation angle (PA) before and after each treatment. Treatments consisted of either stretching (S) or mock stretching (MS). The S treatment involved four 30 second periods of stretching with 15 seconds of rest in between. During the MS treatment subjects were maintained in the same relative position as the S treatment, but were not stretched. RESULTS: There were no significant changes observed in PA from pre to post measurements, though during stretch PA was significantly reduced (p≤0.05). MVC was significantly reduced in the S treatments (p≤0.01). CONCLUSIONS: Stretching had little lasting effect on PA, while MVC was significantly reduced. This finding indicates PA is likely not strongly linked to the MVC reductions observed following stretching