Antineutrino-Induced Charge Current Quasi-Elastic Neutral Hyperon Cross-Section on Argon In Argoneut

This thesis outlines the first measurement of CCQE neutral hyperon production cross section in a liquid argon time projection chamber (LArTPC) through a topological study [1] and presents the ongoing progress of the addition of a calorimetric study. The analysis uses 1.20 £ 1020 protons-on-target, in the NuMI beam operating in the low energy antineutrino mode. The results of the topological study provide a total cross section measurement at the mean production energy of 3.42 GeV for CCQE neutral hyperons. The result of the topological study is consistent with the NUANCE cross section model and sets a 90% confidence level on the upper limit of the cross section. The calorimetric study is ongoing and shows promise to provide additional results to compare with results of the topological study [1]. The progress and further steps are presented in this thesis

747-6 Myocardial Blood Flow in Aortic Regurgitation: Comparison of Global and Regional Blood Flow to Regional Wall Stresses

The impact of regional wall stress (WS) abnormalities on regional coronary flow (CBF) in aortic regurgitation (AR) is not known. However, the existence of such a relation is of potential importance since it might account in part for LV dysfunction and myocardial fibrosis seen in AR, and could suggest therapeutic strategies. We have previously developed and validated a method for calculating regional WS in the radial, circumferential and meridional directions from mid wall (MW) to apex (AP) and endocardium (ENDO) to epicardium (EPI) using a 4000 element model of the LV To define the relation of regional WS and CSF in AR, we applied our LV model in 5 normal (NL) and 4 AR rabbits in which regional CBF was measured using fluorescent microspheres. CBF and radial WS were as follows:CBF (ml/min/gm)Radial WS (×103dynes/cm2)MWAPMWAPNLEPI2.491.308329*ENDO2.090.74133133*AREPI1.821.82*8638*ENDO1.410.77*133133**=p<0.001 (EPI vs ENDO for CSF, EPI to ENDO gradient in AR vs NL for radial WS)Thus, in AR, transmural CBF distribution varies significantly at the apex, while this tendency is less marked and less consistent in NL. No discernable transmural variation was apparent elsewhere in either group. These differences paralleled inversely the transmural variations in radial WS in AR vs NL. In contrast, meridional WS and circumferential WS were uniformly and significantly higher in AR than NL at apex and base (all p < 0.001), a pattern which bore no relation to regional CSF pattern. Thus, regional radial WS influences regional transmural CBF pattern in AR. The importance of this relation to regional LV function and regional myocardial fibrosis in AR now must be assessed

Impact of alpha-tocopherol deficiency and supplementation on sacrocaudalis and gluteal muscle fiber histopathology and morphology in horses.

BackgroundA subset of horses deficient in alpha-tocopherol (α-TP) develop muscle atrophy and vitamin E-responsive myopathy (VEM) characterized by mitochondrial alterations in the sacrocaudalis dorsalis medialis muscle (SC).ObjectivesTo quantify muscle histopathologic abnormalities in subclinical α-TP deficient horses before and after α-TP supplementation and compare with retrospective (r)VEM cases.AnimalsProspective study; 16 healthy α-TP-deficient Quarter Horses. Retrospective study; 10 retrospective vitamin E-responsive myopathy (rVEM) cases .MethodsBlood, SC, and gluteus medius (GM) biopsy specimens were obtained before (day 0) and 56 days after 5000 IU/450 kg horse/day PO water dispersible liquid α-TP (n = 8) or control (n = 8). Muscle fiber morphology and mitochondrial alterations were compared in samples from days 0 and 56 and in rVEM cases.ResultsMitochondrial alterations more common than our reference range (<2.5% affected fibers) were present in 3/8 control and 4/8 treatment horses on day 0 in SC but not in GM (mean, 2.2; range, 0%-10% of fibers). Supplementation with α-TP for 56 days did not change the percentage of fibers with mitochondrial alterations or anguloid atrophy, or fiber size in GM or SC. Clinical rVEM horses had significantly more mitochondrial alterations (rVEM SC, 13% ± 7%; GM, 3% ± 2%) and anguloid atrophy compared to subclinical day 0 horses.Conclusions and clinical importanceClinically normal α-TP-deficient horses can have mitochondrial alterations in the SC that are less severe than in atrophied VEM cases and do not resolve after 56 days of α-TP supplementation. Preventing α-TP deficiency may be of long-term importance for mitochondrial viability

Atypical gaze-following behaviour in infants with congenital heart disease

BACKGROUND Neurodevelopmental impairments are the most prevalent non-cardiac long-term sequelae in children with complex congenital heart disease (CHD). Deficits include the social-emotional and social-cognitive domains. Little is known about the predecessors of social-cognitive development in infants with CHD during the first year of life. Gaze-following behaviour can be used to measure early social-cognitive abilities. AIMS To assess gaze-following development in infants with CHD compared to healthy controls. STUDY DESIGN Prospective cohort study. PARTICIPANTS Twenty-three infants who underwent neonatal correction for CHD and 84 healthy controls. OUTCOME MEASURES Gaze-following behaviour was assessed by eye tracking at 6 and 12 months. Difference scores for first fixation, fixation frequency and fixation duration towards the gaze-cued object were calculated across 6 trials and compared between groups at both testing time points while adjusting for known confounders. Linear mixed models were calculated to assess the longitudinal trajectory of gaze-following development while accounting for the nested and dependent data structure. RESULTS At 6 months, no difference in gaze-following behaviour between CHD and healthy controls was found. At 12 months, fixation frequency towards the gaze-cued was lower and looking duration was shorter in CHD compared to controls (p = 0.0077; p = 0.0068). Infants with CHD showed less increase with age in the fixation frequency towards the congruent object (p = 0.041) compared to controls. CONCLUSION During the first year of life, gaze-following development diverges in infants with CHD compared to healthy controls. Further research is needed to investigate the clinical relevance of these findings and the association with later social-cognitive development

A Method for Designing Conforming Folding Propellers

As the aviation vehicle design environment expands due to the in flux of new technologies, new methods of conceptual design and modeling are required in order to meet the customer's needs. In the case of distributed electric propulsion (DEP), the use of high-lift propellers upstream of the wing leading edge augments lift at low speeds enabling smaller wings with sufficient takeoff and landing performance. During cruise, however, these devices would normally contribute significant drag if left in a fixed or windmilling arrangement. Therefore, a design that stows the propeller blades is desirable. In this paper, we present a method for designing folding-blade configurations that conform to the nacelle surface when stowed. These folded designs maintain performance nearly identical to their straight, non-folding blade counterparts

Drag Reduction Through Distributed Electric Propulsion

One promising application of recent advances in electric aircraft propulsion technologies is a blown wing realized through the placement of a number of electric motors driving individual tractor propellers spaced along each wing. This configuration increases the maximum lift coefficient by providing substantially increased dynamic pressure across the wing at low speeds. This allows for a wing sized near the ideal area for maximum range at cruise conditions, imparting the cruise drag and ride quality benefits of this smaller wing size without decreasing takeoff and landing performance. A reference four-seat general aviation aircraft was chosen as an exemplary application case. Idealized momentum theory relations were derived to investigate tradeoffs in various design variables. Navier-Stokes aeropropulsive simulations were performed with various wing and propeller configurations at takeoff and landing conditions to provide insight into the effect of different wing and propeller designs on the realizable effective maximum lift coefficient. Similar analyses were performed at the cruise condition to ensure that drag targets are attainable. Results indicate that this configuration shows great promise to drastically improve the efficiency of small aircraft

The functional role of biodiversity in ecosystems: incorporating trophic complexity

Understanding how biodiversity affects functioning of ecosystems requires integrating diversity within trophic levels (horizontal diversity) and across trophic levels (vertical diversity, including food chain length and omnivory). We review theoretical and experimental progress toward this goal. Generally, experiments show that biomass and resource use increase similarly with horizontal diversity of either producers or consumers. Among prey, higher diversity often increases resistance to predation, due to increased probability of including inedible species and reduced efficiency of specialist predators confronted with diverse prey. Among predators, changing diversity can cascade to affect plant biomass, but the strength and sign of this effect depend on the degree of omnivory and prey behaviour. Horizontal and vertical diversity also interact: adding a trophic level can qualitatively change diversity effects at adjacent levels. Multitrophic interactions produce a richer variety of diversity‐functioning relationships than the monotonic changes predicted for single trophic levels. This complexity depends on the degree of consumer dietary generalism, trade‐offs between competitive ability and resistance to predation, intraguild predation and openness to migration. Although complementarity and selection effects occur in both animals and plants, few studies have conclusively documented the mechanisms mediating diversity effects. Understanding how biodiversity affects functioning of complex ecosystems will benefit from integrating theory and experiments with simulations and network‐based approaches

Antimatter and Matter Production in Heavy Ion Collisions at CERN (The NEWMASS Experiment NA52)

Besides the dedicated search for strangelets NA52 measures light (anti)particle and (anti)nuclei production over a wide range of rapidity. Compared to previous runs the statistics has been increased in the 1998 run by more than one order of magnitude for negatively charged objects at different spectrometer rigidities. Together with previous data taking at a rigidity of -20 GeV/c we obtained 10^6 antiprotons 10^3 antideuterons and two antihelium3 without centrality requirements. We measured nuclei and antinuclei (p,d,antiprotons, antideuterons) near midrapidity covering an impact parameter range of b=2-12 fm. Our results strongly indicate that nuclei and antinuclei are mainly produced via the coalescence mechanism. However the centrality dependence of the antibaryon to baryon ratios show that antibaryons are diminished due to annihilation and breakup reactions in the hadron dense environment. The volume of the particle source extracted from coalescence models agrees with results from pion interferometry for an expanding source. The chemical and thermal freeze-out of nuclei and antinuclei appear to coincide with each other and with the thermal freeze-out of hadrons.Comment: 12 pages, 8 figures, to appear in the proceedings of the conference on 'Fundamental Issues in Elementary Matter' Bad Honnef, Germany, Sept. 25-29, 200

Dynamics of Resonances in Strongly Interacting Systems

The effects of the propagation of particles which have a finite life-time and an according broad distribution in their mass spectrum are discussed in the context of a transport descriptions. In the first part some example cases of mesonic modes in nuclear matter at finite densities and temperatures are presented. These equilibrium calculations illustrate the dynamical range of spectral distributions to be adequately covered by non-equilibrium description of the dynamics of two nuclei colliding at high energies. The second part addresses the problem of transport descriptions which properly account for the damping width of the particles. A systematic and general gradient approximation is presented in the form of diagrammatic rules which permit to derive a self-consistent transport scheme from the Kadanoff--Baym equation. The scheme is conserving and thermodynamically consistent provided the self-energies are obtained within the Phi-derivable two-particle irreducible (2PI) method of Baym. The merits, the limitations and partial cures of the limitations of this transport scheme are discussed in detail.Comment: To appear in the proceedings of the International Conference "Progress in Nonequilibrium Green's Functions III", Kiel, 22.-26. August 200