368 research outputs found
Non Thermal Irreversible Electroporation: Novel Technology for Vascular Smooth Muscle Cells Ablation
Non thermal Irreversible electroporation (NTIRE) is a new tissue ablation method that induces selective damage only to the cell membrane while sparing all other tissue components. Our group has recently showed that NTIRE attenuated neointimal formation in rodent model. The goal of this study was to determine optimal values of NTIRE for vascular smooth muscle cell (VSMC) ablation.33 Sprague-Dawley rats were used to compare NTIRE protocols. Each animal had NTIRE applied to its left common carotid artery using a custom-made electrodes. The right carotid artery was used as control. Electric pulses of 100 microseconds were used. Eight IRE protocols were compared: 1-4) 10 pulses at a frequency of 10 Hz with electric fields of 3500, 1750, 875 and 437.5 V/cm and 5-8) 45 and 90 pulses at a frequency of 1 Hz with electric fields of 1750 and 875 V/cm. Animals were euthanized after one week. Histological analysis included VSMC counting and morphometry of 152 sections. Selective slides were stained with elastic Van Gieson and Masson trichrome to evaluate extra-cellular structures. The most efficient protocols were 10 pulses of 3500 V/cm at a frequency of 10 Hz and 90 pulses of 1750 V/cm at a frequency of 1 Hz, with ablation efficiency of 89+/-16% and 94+/-9% respectively. Extra-cellular structures were not damaged and the endothelial layer recovered completely.NTIRE is a promising, efficient and simple novel technology for VMSC ablation. It enables ablation within seconds without causing damage to extra-cellular structures, thus preserving the arterial scaffold and enabling endothelial regeneration. This study provides scientific information for future anti-restenosis experiments utilizing NTIRE
High-E_T dijet photoproduction at HERA
The cross section for high-E_T dijet production in photoproduction has been
measured with the ZEUS detector at HERA using an integrated luminosity of 81.8
pb-1. The events were required to have a virtuality of the incoming photon,
Q^2, of less than 1 GeV^2 and a photon-proton centre-of-mass energy in the
range 142 < W < 293 GeV. Events were selected if at least two jets satisfied
the transverse-energy requirements of E_T(jet1) > 20 GeV and E_T(jet2) > 15 GeV
and pseudorapidity requirements of -1 < eta(jet1,2) < 3, with at least one of
the jets satisfying -1 < eta(jet) < 2.5. The measurements show sensitivity to
the parton distributions in the photon and proton and effects beyond
next-to-leading order in QCD. Hence these data can be used to constrain further
the parton densities in the proton and photon.Comment: 36 pages, 13 figures, 20 tables, including minor revisions from
referees. Accepted by Phys. Rev.
CT Image Segmentation Using FEM with Optimized Boundary Condition
The authors propose a CT image segmentation method using structural analysis that is useful for objects with structural dynamic characteristics. Motivation of our research is from the area of genetic activity. In order to reveal the roles of genes, it is necessary to create mutant mice and measure differences among them by scanning their skeletons with an X-ray CT scanner. The CT image needs to be manually segmented into pieces of the bones. It is a very time consuming to manually segment many mutant mouse models in order to reveal the roles of genes. It is desirable to make this segmentation procedure automatic. Although numerous papers in the past have proposed segmentation techniques, no general segmentation method for skeletons of living creatures has been established. Against this background, the authors propose a segmentation method based on the concept of destruction analogy. To realize this concept, structural analysis is performed using the finite element method (FEM), as structurally weak areas can be expected to break under conditions of stress. The contribution of the method is its novelty, as no studies have so far used structural analysis for image segmentation. The method's implementation involves three steps. First, finite elements are created directly from the pixels of a CT image, and then candidates are also selected in areas where segmentation is thought to be appropriate. The second step involves destruction analogy to find a single candidate with high strain chosen as the segmentation target. The boundary conditions for FEM are also set automatically. Then, destruction analogy is implemented by replacing pixels with high strain as background ones, and this process is iterated until object is decomposed into two parts. Here, CT image segmentation is demonstrated using various types of CT imagery
EUDAQ - A data acquisition software framework for common beam telescopes
EUDAQ is a generic data acquisition software developed for use in conjunction with common beam telescopes at charged particle beam lines. Providing high-precision reference tracks for performance studies of new sensors, beam telescopes are essential for the research and development towards future detectors for high-energy physics. As beam time is a highly limited resource, EUDAQ has been designed with reliability and ease-of-use in mind. It enables flexible integration of different independent devices under test via their specific data acquisition systems into a top-level framework. EUDAQ controls all components globally, handles the data flow centrally and synchronises and records the data streams. Over the past decade, EUDAQ has been deployed as part of a wide range of successful test beam campaigns and detector development applications
Measurement of the cross-section ratio sigma_{psi(2S)}/sigma_{J/psi(1S)} in deep inelastic exclusive ep scattering at HERA
The exclusive deep inelastic electroproduction of and
at an centre-of-mass energy of 317 GeV has been studied with the ZEUS
detector at HERA in the kinematic range GeV,
GeV and GeV, where is the photon virtuality, is the
photon-proton centre-of-mass energy and is the squared four-momentum
transfer at the proton vertex. The data for GeV were taken in
the HERA I running period and correspond to an integrated luminosity of 114
pb. The data for GeV are from both HERA I and HERA II
periods and correspond to an integrated luminosity of 468 pb. The decay
modes analysed were and for the
and for the . The cross-section ratio
has been measured as a function of
and . The results are compared to predictions of QCD-inspired
models of exclusive vector-meson production.Comment: 24 pages, 8 figure
Toxocariasis in children attending a Public Health Service Pneumology Unit in Paraná State, Brazil
The enzyme-linked immunosorbent assay (ELISA) is the most widely used tool to detect anti-Toxocara IgG antibodies for both serodiagnostic and seroepidemiological surveys on human toxocariasis. In the last eight years a high prevalence of toxocariasis (32.2-56.0%) has been reported in children attending public health units from municipalities in the state of Paraná, Brazil. Therefore, the aim of this work was to compare the frequency found among the general child population with that of children attending a public pneumology service in Maringá, Paraná, Brazil and describe the laboratorial, clinical and epidemiological findings. The research was conducted at the Consórcio Público Intermunicipal de Saúde do Setentrião Paranaense (CISAMUSEP) from July 2009 to July 2010 among children aged between one and 15 years. From a total of 167 children studied, only 4.2% (7/167) tested positive for anti-Toxocara spp. IgG antibodies and presented mild eosinophilia (2/7), increased serum IgE levels (6/7) and a positive allergy test for mites (5/7). The presence of pets (dogs or cats) at home did not correlate with the seroprevalence. In conclusion, cases of toxocariasis involving the respiratory tract are rare in children attending a public health pneumology unit in the northwestern region of Paraná State, despite the high prevalence of this type of toxocariasis among the infantile population attending Basic Health Units in the same geographical area
Inclusive jet cross sections and dijet correlations in photoproduction at HERA
Inclusive jet cross sections in photoproduction for events containing a
meson have been measured with the ZEUS detector at HERA using an integrated
luminosity of . The events were required to have a
virtuality of the incoming photon, , of less than 1 GeV, and a
photon-proton centre-of-mass energy in the range . The measurements are compared with next-to-leading-order (NLO) QCD
calculations. Good agreement is found with the NLO calculations over most of
the measured kinematic region. Requiring a second jet in the event allowed a
more detailed comparison with QCD calculations. The measured dijet cross
sections are also compared to Monte Carlo (MC) models which incorporate
leading-order matrix elements followed by parton showers and hadronisation. The
NLO QCD predictions are in general agreement with the data although differences
have been isolated to regions where contributions from higher orders are
expected to be significant. The MC models give a better description than the
NLO predictions of the shape of the measured cross sections.Comment: 43 pages, 12 figures, charm jets ZEU
Measurement of neutral current e+/-p cross sections at high Bjorken x with the ZEUS detector
The neutral current e+/-p cross section has been measured up to values of
Bjorken x of approximately 1 with the ZEUS detector at HERA using an integrated
luminosity of 187 inv. pb of e-p and 142 inv. pb of e+p collisions at sqrt(s) =
318GeV. Differential cross sections in x and Q2, the exchanged boson
virtuality, are presented for Q2 geq 725GeV2. An improved reconstruction method
and greatly increased amount of data allows a finer binning in the high-x
region of the neutral current cross section and leads to a measurement with
much improved precision compared to a similar earlier analysis. The
measurements are compared to Standard Model expectations based on a variety of
recent parton distribution functions.Comment: 39 pages, 9 figure
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