1,014 research outputs found

    Operation of the T2K time projection chambers

    Full text link
    The three time projection chambers of the T2K near detector are micro pattern gaseous detectors based on bulk micromegas technology. They have been operated successfully during the first two physics runs of the experiment. Their design, operation, and performance are presented.Comment: 9 pages, 9 figures, proceedings of MPGD2011, submitted to JINS

    Skeletal anomalies in dusky grouper Epinephelus marginatus (Lowe 1834) juveniles reared with different methodologies and larval densities

    Get PDF
    The first attempts to reproduce dusky grouper (Epinephelus marginatus, Lowe 1834) under controlled conditions started in 1995, but the egg and larvae quality was very low. Mass production is still encountering many difficulties, mainly concentrated in the larval period when very high mortality rates are observed, confirming what has been observed in the rearing of other grouper species. The main bottlenecks have been identified as the difficulty to properly nourish the larvae, stress shock syndrome, and the high deformation rates. We analysed 633 dusky grouper larvae and juveniles (0.2–7.2 cm total length, TL), sampled during two larval rearing cycles carried out in 2001 and 2002 in Italy. The specimens at different development stages were stained in toto for bone and cartilage and examined for skeletal anomalies during dusky grouper ontogenesis. The incidence of anomalies in groupers hatched from the same egg batch but reared using two different methods (green waters and semi-intensive rearing) and three stocking densities (8, 16 and 28 larvae/l) was compared, with a view to providing tools for identifying the most appropriate larval rearing method in order to at least limit the onset of skeletal anomalies. Our results suggest that during development no particular skeletal anomaly patterns (or fate) can be clearly identified as a high variability was observed in malformation typologies and the regions affected. No significant differences in the morphological quality between groupers reared using semi-intensive (LV02 lot) and green water (GW02-01 lot) methodologies were observed, whilst groupers reared at the highest stocking density (28 larvae/l) showed the highest frequency of deformed individuals (75.8%), the highest malformation charge (average of 5.5 anomalies per deformed individual), the largest range of anomaly typologies (38), and the highest incidence of individuals with at least one severe anomaly (30.9%). Whilst in green waters no evident effects of larvae density were observed on survival rates, the survival rate in large volume reared individuals (17.5%) was considerably higher with respect to those reared in green waters (0.2%) at 7–8 larvae/l. This indicates that the semi-intensive methodology should be considered more effective in enhancing the survival rate of dusky grouper larvae

    An update of pitfalls in prostate mpMRI: a practical approach through the lens of PI-RADS v. 2 guidelines

    Get PDF
    ObJECTIVES: The aim of the current report is to provide an update in the imaging interpretation of prostate cancer on multiparametric magnetic resonance imaging (mpMRI), with a special focus on how to discriminate pathological tissue from the most common pitfalls that may be encountered during daily clinical practice using the Prostate Imaging Reporting and Data System (PI-RADS) version 2 guidelines. METHODS: All the cases that are shown in this pictorial review comply with the European Society of Urogenital Radiology (ESUR) guidelines for technical mpMRI requirements. RESULTS: Despite the standardised manner to report mpMRI (PI-RADS v. 2), some para-physiologic appearances of the prostate can mimic cancer. As such, it is crucial to be aware of these pitfalls, in order to avoid the under/overestimation of prostate cancer. CONCLUSIONS: A detailed knowledge of normal and abnormal findings in mpMRI of the prostate is pivotal for an accurate management of the wide spectrum of clinical scenarios that radiologists may encounter during their daily practice. TEACHING POINTS: • Some para-physiologic appearances of the prostate may mimic cancer. • Knowledge of normal and abnormal findings in prostate mpMRI is pivotal. • Any radiologist involved in prostate mpMRI reporting should be aware of pitfalls

    Apparent diffusion coefficient by diffusion-weighted magnetic resonance imaging as a sole biomarker for staging and prognosis of gastric cancer

    Get PDF
    Objective: To investigate the role of apparent diffusion coefficient (ADC) from diffusion-weighted magnetic resonance imaging (DW-MRI) when applied to the 7th TNM classification in the staging and prognosis of gastric cancer (GC). Methods: Between October 2009 and May 2014, a total of 89 patients with non-metastatic, biopsy proven GC underwent 1.5T DW-MRI, and then treated with radical surgery. Tumor ADC was measured retrospectively and compared with final histology following the 7th TNM staging (local invasion, nodal involvement and according to the different groups — stage I, II and III). Kaplan-Meier curves were also generated. The follow-up period is updated to May 2016. Results: Median follow-up period was 33 months and 45/89 (51%) deaths from GC were observed. ADC was significantly different both for local invasion and nodal involvement (P<0.001). Considering final histology as the reference standard, a preoperative ADC cut-off of 1.80×10–3 mm2 /s could distinguish between stages I and II and an ADC value of ≤1.36×10–3 mm2 /s was associated with stage III (P<0.001). Kaplan-Meier curves demonstrated that the survival rates for the three prognostic groups were significantly different according to final histology and ADC cut-offs (P<0.001). Conclusions: ADC is different according to local invasion, nodal involvement and the 7th TNM stage groups for GC, representing a potential, additional prognostic biomarker. The addition of DW-MRI could aid in the staging and risk stratification of GC

    Degenerate PCR method for identification of an antiapoptotic gene in BHV-1

    Get PDF
    To investigate on the hypothetical presence of an antiapoptotic gene, we utilized the CODEHOP (COnsensus-DEgenerate Hybrid Oligonucleotide Primers) strategy amplifying unknown sequences from a background of genomic (bovine herpesvirus type-1) BHV-1 DNA. An alignment of carboxyl-terminal domains belonging to three proteins encoded by gamma 34.5, MyD116 and GADD34 genes, was carried out to design degenerate PCR primers in highly conserved regions. This allowed the amplification of a 110 bp fragment. This fragment was subjected to automatic sequencing and DNA sequence analysis revealed that its position resided between the nt 14363 and the nt 14438 in bovine herpesvirus type-1 (BHV-1) Cooper strain sharing an identity of 86% (UL14). Transient transfections showed that ULI 4 protein is efficient in protecting MDBK and K562 cells from sorbitol induced apoptosis. The protein's anti-apoptotic function may derive from its heat shock protein-like properties

    Imaging quality and prostate MR: it's time to improve

    Get PDF
    The PI-RADS guidelines set out the minimal technical requirements for the acquisition of multiparametric magnetic resonance imaging (mpMRI) of the prostate. However, the rapid diffusion of this technique has inevitably led to variability in scan quality among centres across the UK and the world. Suboptimal image acquisitionreduces the sensitivity and specificity of this technique for the detection of clinically significant prostate cancer and result in clinicians losing confidence in the technique.Two expert panels (one from the UK and one from the ESUR/ESUI) have stressed the importance to establish quality criteria for the acquisition ofmpMRI of the prostate.A first attempt to address this issue has been the publication of the Prostate Imaging Quality (PI-QUAL) score, whichassesses the mpMRI quality against a set of objectivecriteria (PI-RADS version 2.1 guidelines) together with criteria obtained from the image.PI-QUAL represents the first step towards the standardisation of a scoring system toassess the quality of prostate mpMRIprior to reporting and allows clinicians to have more confidence in using the scan to determine patient care. Further refinements after robust consensus among experts at an international level need to be agreed before its widespread adoption in the clinical setting

    Progress in Prostate MRI Quality

    Get PDF

    Solar neutrino detection in a large volume double-phase liquid argon experiment

    Full text link
    Precision measurements of solar neutrinos emitted by specific nuclear reaction chains in the Sun are of great interest for developing an improved understanding of star formation and evolution. Given the expected neutrino fluxes and known detection reactions, such measurements require detectors capable of collecting neutrino-electron scattering data in exposures on the order of 1 ktonne yr, with good energy resolution and extremely low background. Two-phase liquid argon time projection chambers (LAr TPCs) are under development for direct Dark Matter WIMP searches, which possess very large sensitive mass, high scintillation light yield, good energy resolution, and good spatial resolution in all three cartesian directions. While enabling Dark Matter searches with sensitivity extending to the "neutrino floor" (given by the rate of nuclear recoil events from solar neutrino coherent scattering), such detectors could also enable precision measurements of solar neutrino fluxes using the neutrino-electron elastic scattering events. Modeling results are presented for the cosmogenic and radiogenic backgrounds affecting solar neutrino detection in a 300 tonne (100 tonne fiducial) LAr TPC operating at LNGS depth (3,800 meters of water equivalent). The results show that such a detector could measure the CNO neutrino rate with ~15% precision, and significantly improve the precision of the 7Be and pep neutrino rates compared to the currently available results from the Borexino organic liquid scintillator detector.Comment: 21 pages, 7 figures, 6 table

    Measurement of inclusive charged current interactions on carbon in a few-GeV neutrino beam

    Get PDF
    The SciBooNE Collaboration reports a measurement of inclusive charged current interactions of muon neutrinos on carbon with an average energy of 0.8 GeV using the Fermilab Booster Neutrino Beam. We compare our measurement with two neutrino interaction simulations: NEUT and NUANCE. The charged current interaction rates (product of flux and cross section) are extracted by fitting the muon kinematics, with a precision of 6-15% for the energy dependent and 3% for the energy integrated analyses. We also extract CC inclusive interaction cross sections from the observed rates, with a precision of 10-30% for the energy dependent and 8% for the energy integrated analyses. This is the first measurement of the CC inclusive cross section on carbon around 1 GeV. These results can be used to convert previous SciBooNE cross section ratio measurements to absolute cross section values.Comment: 21 pages, 16 figures. Accepted by Phys. Rev. D. Minor revisions to match the accepted versio
    corecore