Bat response to differing fire severity in mixed-conifer forest California, USA

Wildlife response to natural disturbances such as fire is of conservation concern to managers, policy makers, and scientists, yet information is scant beyond a few well-studied groups (e.g., birds, small mammals). We examined the effects of wildfire severity on bats, a taxon of high conservation concern, at both the stand (<1 ha) and landscape scale in response to the 2002 McNally fire in the Sierra Nevada region of California, USA. One year after fire, we conducted surveys of echolocation activity at 14 survey locations, stratified in riparian and upland habitat, in mixed-conifer forest habitats spanning three levels of burn severity: unburned, moderate, and high. Bat activity in burned areas was either equivalent or higher than in unburned stands for all six phonic groups measured, with four groups having significantly greater activity in at least one burn severity level. Evidence of differentiation between fire severities was observed with some Myotis species having higher levels of activity in stands of high-severity burn. Larger-bodied bats, typically adapted to more open habitat, showed no response to fire. We found differential use of riparian and upland habitats among the phonic groups, yet no interaction of habitat type by fire severity was found. Extent of high-severity fire damage in the landscape had no effect on activity of bats in unburned sites suggesting no landscape effect of fire on foraging site selection and emphasizing stand-scale conditions driving bat activity. Results from this fire in mixed-conifer forests of California suggest that bats are resilient to landscape-scale fire and that some species are preferentially selecting burned areas for foraging, perhaps facilitated by reduced clutter and increased post-fire availability of prey and roost

Evaluation of the protein quality of fish meals by means of the NPU method

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Evaluation of in vivo techniques for the determination of apparent ileal amino acid digestibilities in feedstuffs for piglets

Three in vivo techniques were evaluated in terms of their suitability for determination of the apparent ileal amino acid digestibility (AID) of protein sources for piglets. The techniques were: ileo-rectal anastomosis (IRA), cannulation at the distal ileum and a slaughter technique. A standard diet and three diets in which 20% of the standard diet was substituted with either skim milk powder (SMP), fish meal or roasted full-fat soya beans (FFS) were used. Piglets were weaned at 21 days of age, and the respective diets were fed in 24 equal hourly portions per day from days 29-37. Ileal digesta was collected from day 33-37 in IRA and cannulated piglets. Piglets used for the slaughter technique were killed at 37 days of age and ileal digesta was collected. Chromium III oxide was used as an indigestible marker with all three techniques. Although AID means did not differ (p > 0.05) between the different techniques, the cannulation technique resulted in the lowest variation (standard error of the mean) of all treatments (8.2 vs 13.7 and 14.1 for the slaughter and IRA-techniques respectively). AID means obtained using the cannula technique were 1.8 percentage units higher for the SMP diet than values obtained using the other techniques (83.2 versus 81.4 %), and up to 9.3 percentage units higher for the FFS diet (75.4 versus 66.1 %). Growth data suggested that the cannulation technique caused less trauma for the piglets than the IRA-technique. IRA-piglets had not yet regained their initial weaning weight by 37 days of age, while the other piglets gained weight over the trial period. The cannulation technique is the most attractive method for use with piglets in terms of the lower variation in digestibility values. Practical aspects such as ease of handling and sampling, surgical trauma and piglet stress, are also important and contribute to the selection of the cannula technique as the most appropriate. (South African Journal of Animal Science, 2000, 30(1): 7-15

A Local-Sparing Design Methodology for Fault-Tolerant MultiprocessorsaaThis research was supported in part by the Office of Naval Research under Contract N00014-85K0531 and N00014-90J1860, and in part by NSF Grants MIP-9210049 and MIP-9200526.

AbstractWe present a comprehensive design methodology for constructing low-cost multiprocessors that use local spares to tolerate the failure of either processor clusters or individual processors. We first formalize the concepts of global- and local-sparing in terms of graph automorphisms. We then present a method for partitioning a multiprocessor graph by its automorphisms and for incorporating local-sparing to tolerate faults. We emphasize local-sparing designs, since they offer higher reliability-to-cost ratios and can reconfigure faster and in a localized manner. When the spare clusters in each local subsystem are certain sizes, our designs are optimal in the number of spare intersubsystem links. They are all efficient (optimal in some cases) in terms of the number of spare intrasubsystem links. We present switch-based implementations that significantly reduces the spare link complexities of the designs. These implementations are equally efficient for any spare cluster size, so they yield efficient local-sparing designs that can tolerate individual processor faults (cluster size of one). Algorithms for fast, localized, and incremental reconfiguration of our FT designs are also developed. Finally, we demonstrate that our local-sparing designs have higher reliability-to-cost ratios than previous designs

Rebuttal to Hasan and Pedraza in comments and controversies: "Improving the reliability of manual and automated methods for hippocampal and amygdala volume measurements"

Here we address the critiques offered by Hasan and Pedraza to our recently published manuscript comparing the performance of two automated segmentation programs, FSL/FIRST and FreeSurfer (Morey R, Petty C, Xu Y, Pannu Hayes J, Wagner H, Lewis D, LaBar K, Styner M, McCarthy G. (2009): A comparison of automated segmentation and manual tracing for quantifying of hippocampal and amygdala volumes. Neuroimage 45:855-866). We provide an assessment and discussion of their specific critiques. Hasan and Pedraza bring up some important points concerning our omission of sample demographic features and inclusion of left and right hemisphere volumes as independent measures in correlational analyses. We present additional data on demographic attributes of our sample and correlations analyzed separately on left and right hemispheres of the amygdala and hippocampus. While their commentary aids the reader to more critically asses our study, it falls short of substantiating that our omissions ought to lead readers to significantly revise their interpretations. Further research will help to disentangle the advantages and limitations of the various freely-available automated segmentation software packages

A Quantum-Mechanical Equivalent-Photon Spectrum for Heavy-Ion Physics

In a previous paper, we calculated the fully quantum-mechanical cross section for electromagnetic excitation during peripheral heavy-ion collisions. Here, we examine the sensitivity of that cross section to the detailed structure of the projectile and target nuclei. At the transition energies relevant to nuclear physics, we find the cross section to be weakly dependent on the projectile charge radius, and to be sensitive to only the leading momentum-transfer dependence of the target transition form factors. We exploit these facts to derive a quantum-mechanical ``equivalent-photon spectrum'' valid in the long-wavelength limit. This improved spectrum includes the effects of projectile size, the finite longitudinal momentum transfer required by kinematics, and the response of the target nucleus to the off-shell photon.Comment: 19 pages, 5 figure

Pulsed Power Accelerators at CEM-UT

An overview of four accelerator programs utilizing pulsed power is presented. The goals of each project, a description of the power supplies and launchers utilized and test results from each program are provided. The four projects presented illustrate a variety of uses for electromagnetic (EM) launchers and the potential advantages and disadvantages of four different launcher systems. Included in the paper are micrometeorite impact studies of 50 to 500 μm diameter glass beads accelerated up to 11 km/s with plasma armatures and 2.5- kg solid armature packages launched at 2.6 km/s (a record 8.1 MJ of muzzle energy). A compact rep-rateable augmented rail launcher and compulsator system weighing less than 1,100 kg is also described. Finally a skid mounted rep-rateable launcher system capable of providing 9 MJ of muzzle energy is discussed.Center for Electromechanic

Effects of inhomogeneous broadening on reflection spectra of Bragg multiple quantum well structures with a defect

The reflection spectrum of a multiple quantum well structure with an inserted defect well is considered. The defect is characterized by the exciton frequency different from that of the host's wells. It is shown that for relatively short structures, the defect produces significant modifications of the reflection spectrum, which can be useful for optoelectronic applications. Inhomogeneous broadening is shown to affect the spectrum in a non-trivial way, which cannot be described by the standard linear dispersion theory. A method of measuring parameters of both homogeneous and inhomogeneous broadenings of the defect well from a single CW reflection spectrum is suggested.Comment: 27 pages, 6 eps figures; RevTe

Pa jel ’ baš moraš studirat na privatnom sveučilištu : privatno sveučilište – bezrazložni trošak ili investicija u budućnost

U radu su prikazani podaci anketiranja studenata Libertas međunarodnog sveučilišta u Zagrebu, jedinog privatnog sveučilišta u Republici Hrvatskoj. Na poziv za sudjelovanje u anketi odazvalo se samo 349 studenata, tako da uzorak nije reprezentativan, nego predstavlja tek informaciju o onima koji su se odlučili u ispitivanju sudjelovati. Ispitanicima su postavljena 44 pitanja koja su obuhvatila čak 126 varijabli. Međutim, rezultati analize prikupljenih podataka ukazuju na to da se ispitanici uglavnom ne razlikuju od neke opće studentske populacije u Republici Hrvatskoj, da su prije svega pokretani istim motivima, motivima osobnog napretka, a ne „mogućnostima” koje bi im prema nekim poznatim stereotipima pružala „posebna” okolina privatnog sveučilišta

Hamiltonian Light-Front Field Theory: Recent Progress and Tantalizing Prospects

Fundamental theories, such as Quantum Electrodynamics (QED) and Quantum Chromodynamics (QCD) promise great predictive power addressing phenomena over vast scales from the microscopic to cosmic scales. However, new non-perturbative tools are required for physics to span from one scale to the next. I outline recent theoretical and computational progress to build these bridges and provide illustrative results for Hamiltonian Light Front Field Theory. One key area is our development of basis function approaches that cast the theory as a Hamiltonian matrix problem while preserving a maximal set of symmetries. Regulating the theory with an external field that can be removed to obtain the continuum limit offers additional possibilities as seen in an application to the anomalous magnetic moment of the electron. Recent progress capitalizes on algorithm and computer developments for setting up and solving very large sparse matrix eigenvalue problems. Matrices with dimensions of 20 billion basis states are now solved on leadership-class computers for their low-lying eigenstates and eigenfunctions.Comment: 8 pages with 2 figure