13,649 research outputs found
Inspection of transparent surfaces using photosensitive paper
Window surface is laid flat on top of photosensitive paper. Opposite side of glass is covered by black cloth. Window edges are then illuminated by light flash through fiber optics. Exposed paper is processed and inspected. Paper shows scratches, bubbles, dust particles, and fingerprints on glass surface
Statistics of Lead Changes in Popularity-Driven Systems
We study statistical properties of the highest degree, or most popular, nodes
in growing networks. We show that the number of lead changes increases
logarithmically with network size N, independent of the details of the growth
mechanism. The probability that the first node retains the lead approaches a
finite constant for popularity-driven growth, and decays as N^{-phi}(ln
N)^{-1/2}, with phi=0.08607..., for growth with no popularity bias.Comment: 4 pages, 4 figures, 2 column revtex format. Minor changes in response
to referee comments. For publication in PR
Hyperadrenocorticism in the Domestic Ferret
Domestic ferrets (Mustela putorius furo) are becoming increasingly common in the United States. They are very popular as household pets and are also used in large numbers as research animals. With the increase in ferret numbers, there has been a corresponding increase in the number and frequency of diseases described. Neoplastic conditions are at the top of the list of problems occurring in ferrets found in the United States. An exceedingly common condition is adrenal disease as a result of adrenocortical hyperplasia, adenoma, or adenocarcinoma. These conditions present as the same clinical syndrome and anyone examining ferrets in a veterinary setting can expect to see many cases of adrenal disease
The impact of consent on observational research: a comparison of outcomes from consenters and non consenters to an observational study
Background
Public health benefits from research often rely on the use of data from personal medical records. When neither patient consent nor anonymisation is possible, the case for accessing such records for research purposes depends on an assessment of the probabilities of public benefit and individual harm.
Methods
In the late 1990s, we carried out an observational study which compared the care given to affluent and deprived women with breast cancer. Patient consent was not required at that time for review of medical records, but was obtained later in the process prior to participation in the questionnaire study. We have re-analysed our original results to compare the whole sample with those who later provided consent.
Results
Two important findings emerged from the re-analysis of our data which if presented initially would have resulted in insufficient and inaccurate reporting. Firstly, the reduced dataset contains no information about women presenting with locally advanced or metastatic cancer and we would have been unable to demonstrate one of our initial key findings: namely a larger number of such women in the deprived group. Secondly, our re-analysis of the consented women shows that significantly more women from deprived areas (51 v 31%, p = 0.018) received radiotherapy compared to women from more affluent areas. Previously published data from the entire sample demonstrated no difference in radiotherapy treatment between the affluent and deprived groups.
Conclusion
The risk benefit assessment made regarding the use of medical records without consent should include the benefits of obtaining research evidence based on 100% of the population and the possibility of inappropriate or insufficient findings if research is confined to consented populations
Phenomenology of the General NMSSM with Gauge Mediated Supersymmetry Breaking
We investigate various classes of Gauge Mediated Supersymmetry Breaking
models and show that the Next-to-Minimal Supersymmetric Standard Model can
solve the mu-problem in a phenomenologically acceptable way. These models
include scenarios with singlet tadpole terms, which are phenomenologically
viable, e.g., in the presence of a small Yukawa coupling <~ 10^{-5}. Scenarios
with suppressed trilinear A-terms at the messenger scale lead naturally to
light CP-odd scalars, which play the r\^ole of pseudo R-axions. A wide range of
parameters of such models satisfies LEP constraints, with CP-even Higgs scalars
below 114 GeV decaying dominantly into a pair of CP-odd scalars.Comment: 24 pages, 6 figures, typos corrected, reference adde
Berry phases for composite fermions: effective magnetic field and fractional statistics
The quantum Hall superfluid is presently the only viable candidate for a
realization of quasiparticles with fractional Berry phase statistics. For a
simple vortex excitation, relevant for a subset of fractional Hall states
considered by Laughlin, non-trivial Berry phase statistics were demonstrated
many years ago by Arovas, Schrieffer, and Wilczek. The quasiparticles are in
general more complicated, described accurately in terms of excited composite
fermions. We use the method developed by Kjonsberg, Myrheim and Leinaas to
compute the Berry phase for a single composite-fermion quasiparticle, and find
that it agrees with the effective magnetic field concept for composite
fermions. We then evaluate the "fractional statistics", related to the change
in the Berry phase for a closed loop caused by the insertion of another
composite-fermion quasiparticle in the interior. Our results support the
general validity of fractional statistics in the quantum Hall superfluid, while
also giving a quantitative account of corrections to it when the quasiparticle
wave functions overlap. Many caveats, both practical and conceptual, are
mentioned that will be relevant to an experimental measurement of the
fractional statistics. A short report on some parts of this article has
appeared previously.Comment: 14 pages, 9 figure
Higgs Signal for h to aa at Hadron Colliders
We assess the prospect of observing a neutral Higgs boson at hadron colliders
in its decay to two spin-zero states, a, for a Higgs mass of 90-130 GeV, when
produced in association with a W or Z boson. Such a decay is allowed in
extensions of the MSSM with CP-violating interactions and in the NMSSM, and can
dominate Higgs boson final states, thereby evading the LEP constraints on
standard Higgs boson production. The light spin-zero state decays primarily via
a to bb and tau+tau-, so this signal channel retains features distinct from the
main backgrounds. Our study shows that at the Tevatron, there may be potential
to observe a few events in the bb tau+tau- or bbbb channels with relatively
small background, although this observation would be statistically limited. At
the LHC, the background problem is more severe, but with cross sections and
integrated luminosities orders of magnitude larger than at the Tevatron, the
observation of a Higgs boson in this decay mode would be possible. The channel
h to aa to bbbb would provide a large statistical significance, with a
signal-to-background ratio on the order of 1:2. In these searches, the main
challenge would be to retain the adequate tagging efficiency of b's and tau's
in the low p_T region.Comment: Version to be published in JHEP. 20 pages, 5 figure
Characterization of a supercoil-dependent S1 sensitive site 5\u27 to the Drosophila melanogaster hsp 26 gene
We have analyzed the prominent supercoil-dependent S1 nuclease cleavage site 5\u27 to hsp 26 in the plasmid 88B13, which contains 11.7 kilobases from the Drosophila locus 67B1. The double stranded cleavage product is generated by initial nicking on the purine strand, six preferred sites occurring between positions -96 and -90 (relative to the start of transcription) with weaker ones extending to position -84, followed by cleavage on the pyrimidine strand at positions -86 and -84. A derivative of 88B13, 88B13-X, was generated by insertion of an Xho I linker at position -84; this does not affect the positions or strand specificity of the S1 cleavage in that region. A small deletion, delta 41.1, removes the homopurine/homopyrimidine stretch from positions -86 to -132 and is no longer sensitive to cleavage by S1 nuclease 5\u27 to hsp 26. Mung bean and P1 nucleases recognize the same site 5\u27 to hsp 26 and give the same general pattern of cleavage. All three nucleases show an initial cleavage of 88B13 DNA at this site at pH 5.5 but not at pH 6.5, indicating that the DNA structure there may be pH dependent in vitro
LAPORAN KASUS: SUSPECT SWINE POX VIRUS DAN TRAUMATIK
Kepincangan atau gangguan lokomotif merupakan salah satu masalah kesehatan yang paling relevan terjadi pada babi. Penyebab kepincangan secara luas dapat diklasifikasikan sebagai dampak dari gangguan genetik, cedera fisik serta infeksi. Swine pox virus atau yang biasa disebut dengan cacar babi merupakan penyakit menular pada babi yang ditandai dengan adanya Iepuh atau pustule dan keropeng pada kulit. Swine pox virus termasuk dalam famili Poxviridae, genus Suipoxvirus, memiliki untaian ds-DNA, serta berukuran 200-250 nm. Pada penatalaksanaan terapi atau pengobatan yang diberikan pada dua kondisi yang sedang dialami ternak babi tersebut dilakukan dengan pemberian anti inflamasi yang diberikan yakni Dexamethasone® 0.75 mg, antibiotik diberikan Vet-Oxy SB® 5 ml/50 kg BB, dan vitamin diberikan Vit B-Kompleks® serta salep kulit (racikan) yang diberikan secara topikal pada area kulit yang terdapat pustule
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