84 research outputs found

    Silicon Drift Detector Readout Electronics for a Compton Camera

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    A prototype detector for Compton camera imaging is under development. A monolithic array of 19 channel Silicon drift detector with on-chip electronics is going to be used as a scatter detector for the prototype system. Custom designed analog and digital readout electronics for this detector was first tested by using a single cell Silicon drift detector. This paper describes the readout architecture and presents the results of the measurement.Comment: 10 pages, 9 figures, submitted to Nucl. Instr. Meth.

    An Evaluation of Periodontal Status and Cytokine Levels in Saliva and Gingival Crevicular Fluid of Patients with Inflammatory Bowel Diseases.

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    AIMS Periodontal diseases and inflammatory bowel diseases (IBD, ulcerative colitis [UC] and Crohn's disease [CD]) have been reported to present with increased salivary and gingival crevicular fluid (GCF) concentrations of cytokines. The aim of this study was to evaluate the salivary and GCF levels of TNF-α, IL-1β, IL-10, and IL-17A and their associations with the periodontal statuses of UC, CD and non-IBD patients, and to analyze the interrelationships among these cytokines, IBD conditions, and periodontal diseases. MATERIALS AND METHODS This cross-sectional study was performed with a total of 131 patients (62 women and 69 men, mean age 42.96±13.02 years). Patients were divided into three groups: UC, CD, and non-IBD. Periodontal status was defined according to the 2017 World Workshop Disease Classification. Salivary and GCF cytokine levels were analyzed using ELISA. RESULTS UC and CD patients diagnosed as having periodontitis and gingivitis presented with significantly higher levels of TNF-α and lower levels of IL-10 as compared with non-IBD patients (p<0.05). UC patients diagnosed with periodontitis exhibited significantly higher scores of bleeding on probing (p = 0.011) and increased salivary and GCF IL-1β levels as compared with CD patients (p = 0.005, and 0.012 respectively). Considering the active and remission status of IBD, salivary IL-1β was found to be correlated with the parameters representing the severity of periodontal diseases in active UC and CD patients. CONCLUSION(S) In the presence of periodontal diseases, UC and CD patients showed different expression levels of TNF-α, IL-1β, and IL-10 in oral secretions as compared with non-IBD patients. This article is protected by copyright. All rights reserved

    Research of microstructure and microbiological indicators of pasta products from non-traditional raw materials

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    Modern trends in the development of pasta production are based on the use of starch-containing raw materials for the production of medicinal and preventive pasta products. In this connection, an important observation is the state of protein and starch in pasta flour, which can be achieved by electron microscopy of the microstructure of macaroni products. Therefore, the study of microstructures and microbiological indicators of pasta from non-traditional raw materials will be relevant. The practical value of the research is characterized by improved consumer properties of pasta made from non-traditional raw materials. The novelty of the research is the development of scientific and technological bases for the production of pasta from non-traditional polycereal raw materials. The results obtained: the analysis of the obtained electronic micro-drawings showed that the microstructure of pasta from non-traditional raw materials corresponds to the standards in comparison with the control sample. The following types of mycotoxins were found in pasta from non-traditional raw materials in permitted quantities: aflatoxin B1, aflatoxin M1, zearalenone, deoxynivalenol, ochratoxin A, fumonisin, patulin, T-2. For example, the amount of zearalenone (mg/kg): in pasta according to recipe No. 1 – 0.0637, according to recipe No. 2 – 0.0251 and according to recipe No. 3 – 0.0758; in flour raw materials – according to recipe No. 1 – 0.1485, according to recipe No. 2 – 0.0261 and according to recipe No. 3 – 0.2

    Botulinum toxin injection versus lateral internal sphincterotomy in the treatment of chronic anal fissure: a non-randomized controlled trial

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    BACKGROUND: Although lateral internal sphincterotomy is the gold-standard treatment for chronic anal fissure, intrasphincteric injection of botulinum toxin seems to be a reliable new option. The aim of this non-randomized study is to compare the effect of lateral internal sphincterotomy and botulinum toxin injection treatments on the outcome and reduction of anal sphincter pressures in patients with chronic anal fissure. METHODS: Patients with chronic anal fissure were treated with either botulinum toxin injection or lateral internal sphincterotomy by their own choice. Maximal resting pressure and maximal squeeze pressure measurements were performed before and 2 weeks after treatments by anal manometry. Patients were followed for fissure relapse during 14 months. RESULTS: Twenty-one consecutive outpatients with posterior chronic anal fissure were enrolled. Eleven patients underwent surgery and ten patients received botulinum toxin injection treatment. Before the treatment, anal pressures were found to be similar in both groups. After the treatment, the maximal resting pressures were reduced from 104 ± 22 mmHg to 86 ± 15 mmHg in the surgery group (p < 0.05) and from 101 ± 23 mmHg to 83 ± 24 mmHg in the botulinum toxin group (p < 0.05). The mean maximal squeeze pressures were reduced from 70 ± 27 mmHg to 61 ± 32 mmHg (p > 0.05) in the surgery group, and from 117 ± 62 mmHg to 76 ± 34 (p < 0.01) in the botulinum toxin group. The fissures were healed in 70 percent of patients in the botulinum group and 82 percent in the surgery group (p > 0.05). There were no relapses during the 14 months of follow up. CONCLUSION: Lateral internal sphincterotomy and botulinum toxin injection treatments both seem to be equally effective in the treatment of chronic anal fissure

    Time course of collagen peak in bile duct-ligated rats

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    <p>Abstract</p> <p>Background</p> <p>One of the most useful experimental fibrogenesis models is the "bile duct-ligated rats". Our aim was to investigate the quantitative hepatic collagen content by two different methods during the different stages of hepatic fibrosis in bile duct-ligated rats on a weekly basis. We questioned whether the 1-wk or 4-wk bile duct-ligated model is suitable in animal fibrogenesis trials.</p> <p>Methods</p> <p>Of the 53 male Wistar rats, 8 (Group 0) were used as a healthy control group. Bile duct ligation (BDL) had been performed in the rest. Bile duct-ligated rates were sacrificed 7 days later in group 1 (10 rats), 14 days later in group 2 (9 rats), 21 days later in group 3(9 rats) and 28 days later in group 4 (9 rats). Eight rats underwent sham-operation (Sham). Hepatic collagen measurements as well as serum levels of liver enzymes and function tests were all analysed.</p> <p>Results</p> <p>The peak level of collagen was observed biochemically and histomorphometricly at the end of third week (P < 0.001 and P < 0.05). Suprisingly, collagen levels had decreased with the course of time such as at the end of fourth week (P < 0.01 and P < 0.05).</p> <p>Conclusion</p> <p>We have shown that fibrosis in bile duct-ligated rats is transient, i.e. reverses spontaneously after 3 weeks. This contrasts any situation in patients where hepatic fibrosis is progressive and irreversible as countless studies performed by many investigators in the same animal model.</p

    Non-Coding Keratin Variants Associate with Liver Fibrosis Progression in Patients with Hemochromatosis

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    Background: Keratins 8 and 18 (K8/K18) are intermediate filament proteins that protect the liver from various forms of injury. Exonic K8/K18 variants associate with adverse outcome in acute liver failure and with liver fibrosis progression in patients with chronic hepatitis C infection or primary biliary cirrhosis. Given the association of K8/K18 variants with endstage liver disease and progression in several chronic liver disorders, we studied the importance of keratin variants in patients with hemochromatosis. Methods: The entire K8/K18 exonic regions were analyzed in 162 hemochromatosis patients carrying homozygous C282Y HFE (hemochromatosis gene) mutations. 234 liver-healthy subjects were used as controls. Exonic regions were PCRamplified and analyzed using denaturing high-performance liquid chromatography and DNA sequencing. Previouslygenerated transgenic mice overexpressing K8 G62C were studied for their susceptibility to iron overload. Susceptibility to iron toxicity of primary hepatocytes that express K8 wild-type and G62C was also assessed. Results: We identified amino-acid-altering keratin heterozygous variants in 10 of 162 hemochromatosis patients (6.2%) and non-coding heterozygous variants in 6 additional patients (3.7%). Two novel K8 variants (Q169E/R275W) were found. K8 R341H was the most common amino-acid altering variant (4 patients), and exclusively associated with an intronic KRT8 IVS7+10delC deletion. Intronic, but not amino-acid-altering variants associated with the development of liver fibrosis. I

    Response of a CMS HGCAL silicon-pad electromagnetic calorimeter prototype to 20-300 GeV positrons

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    The Compact Muon Solenoid Collaboration is designing a new high-granularity endcap calorimeter, HGCAL, to be installed later this decade. As part of this development work, a prototype system was built, with an electromagnetic section consisting of 14 double-sided structures, providing 28 sampling layers. Each sampling layer has an hexagonal module, where a multipad large-area silicon sensor is glued between an electronics circuit board and a metal baseplate. The sensor pads of approximately 1 cm2^2 are wire-bonded to the circuit board and are readout by custom integrated circuits. The prototype was extensively tested with beams at CERN's Super Proton Synchrotron in 2018. Based on the data collected with beams of positrons, with energies ranging from 20 to 300 GeV, measurements of the energy resolution and linearity, the position and angular resolutions, and the shower shapes are presented and compared to a detailed Geant4 simulation

    Performance of the CMS High Granularity Calorimeter prototype to charged pion beams of 20−-300 GeV/c

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    The upgrade of the CMS experiment for the high luminosity operation of the LHC comprises the replacement of the current endcap calorimeter by a high granularity sampling calorimeter (HGCAL). The electromagnetic section of the HGCAL is based on silicon sensors interspersed between lead and copper (or copper tungsten) absorbers. The hadronic section uses layers of stainless steel as an absorbing medium and silicon sensors as an active medium in the regions of high radiation exposure, and scintillator tiles directly readout by silicon photomultipliers in the remaining regions. As part of the development of the detector and its readout electronic components, a section of a silicon-based HGCAL prototype detector along with a section of the CALICE AHCAL prototype was exposed to muons, electrons and charged pions in beam test experiments at the H2 beamline at the CERN SPS in October 2018. The AHCAL uses the same technology as foreseen for the HGCAL but with much finer longitudinal segmentation. The performance of the calorimeters in terms of energy response and resolution, longitudinal and transverse shower profiles is studied using negatively charged pions, and is compared to GEANT4 predictions. This is the first report summarizing results of hadronic showers measured by the HGCAL prototype using beam test data.Comment: To be submitted to JINS
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