Operation of the T2K time projection chambers

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

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

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

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

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

Prostate Imaging Quality (PI-QUAL): A New Quality Control Scoring System for Multiparametric Magnetic Resonance Imaging of the Prostate from the PRECISION trial

The PRECISION trial was a multicentre randomised study that demonstrated that multiparametric magnetic resonance imaging (mpMRI)-targeted biopsy is superior to standard transrectal ultrasound-guided biopsy for the detection of prostate cancer. The outcomes of studies reporting mpMRI-targeted biopsies are dependent on the quality of the mpMRI but there are currently no scoring systems available for evaluating this. We introduced a novel scoring system, the Prostate Imaging Quality (PI-QUAL) score, to assess the quality of scans in the PRECISION trial. PI-QUAL is a score on a Likert scale from 1 to 5, where 1 means that no mpMRI sequences are of diagnostic quality and 5 implies that each sequence is independently of optimal diagnostic quality. Fifty-eight out of 252 (23%) mpMRI scans chosen at random from each of the 22 centres in this trial were evaluated by two experienced radiologists from the coordinating trial centre, in consensus, blinded to pathology results. Overall, the mpMRI quality in the centres participating in PRECISION was good. MpMRI quality was of sufficient diagnostic quality (PI-QUAL ≥3) for 55 scans (95%) and of good or optimal diagnostic quality (PI-QUAL ≥4) for 35 scans (60%). Fifty-five out of 58 (95%) scans were of diagnostic quality for T2WI, followed by DWI (46/58 scans; 79%), and DCE (38/58 scans; 66%). Further validation of this scoring system is warranted. PATIENT SUMMARY: In this study we developed a scoring system (PI-QUAL) to assess the quality of multiparametric magnetic resonance imaging (mpMRI) in prostate cancer detection. We used scans from 22 centres that participated in the PRECISION trial. Although there was room for improvement in images that used intravenous contrast, we found that mpMRI in the PRECISION trial was of sufficient diagnostic quality (PI-QUAL score ≥3) for 95% of the scans

Multiparametric prostate MRI quality assessment using a semi-automated PI-QUAL software program

The technical requirements for the acquisition of multiparametric magnetic resonance imaging (mpMRI) of the prostate have been clearly outlined in the Prostate Imaging Reporting and Data System (PI-RADS) guidelines, but there is still huge variability in image quality among centres across the world. It has been difficult to quantify what constitutes a good-quality image, and a first attempt to address this matter has been the publication of the Prostate Imaging Quality (PI-QUAL) score and its dedicated scoring sheet. This score includes the assessment of technical parameters that can be obtained from the DICOM files along with a visual evaluation of certain features on prostate MRI (e.g., anatomical structures). We retrospectively analysed the image quality of 10 scans from different vendors and magnets using a semiautomated dedicated PI-QUAL software program and compared the time needed for assessing image quality using two methods (semiautomated assessment versus manual filling of the scoring sheet). This semiautomated software is able to assess the technical parameters automatically, but the visual assessment is still performed by the radiologist. There was a significant reduction in the reporting time of prostate mpMRI quality according to PI-QUAL using the dedicated software program compared to manual filling (5'54″ versus 7'59″; p = 0.005). A semiautomated PI-QUAL software program allows the radiologist to assess the technical details related to the image quality of prostate mpMRI in a quick and reliable manner, allowing clinicians to have more confidence that the quality of mpMRI of the prostate is sufficient to determine patient care

Prostate MRI quality: a critical review of the last 5 years and the role of the PI-QUAL score

There is increasing interest in the use of multiparametric magnetic resonance imaging (mpMRI) in the prostate cancer pathway. The European Association of Urology (EAU) and the British Association of Urological Surgeons (BAUS) now advise mpMRI prior to biopsy, and the Prostate Imaging Reporting and Data System (PI-RADS) recommendations set out the minimal technical requirements for the acquisition of mpMRI of the prostate.The widespread and swift adoption of this technique has led to variability in image quality. Suboptimal image acquisition reduces the sensitivity and specificity of mpMRI for the detection and staging of clinically significant prostate cancer.This critical review outlines the studies aimed at improving prostate MR quality that have been published over the last 5 years. These span from the use of specific MR sequences, magnets and coils to patient preparation. The rates of adherence of prostate mpMRI to technical standards in different cohorts across the world are also discussed.Finally, we discuss the first standardised scoring system (i.e., Prostate Imaging Quality, PI-QUAL) that has been created to evaluate image quality, although further iterations of this score are expected in the future

Testing for Network and Spatial Autocorrelation

Testing for dependence has been a well-established component of spatial statistical analyses for decades. In particular, several popular test statistics have desirable properties for testing for the presence of spatial autocorrelation in continuous variables. In this paper we propose two contributions to the literature on tests for autocorrelation. First, we propose a new test for autocorrelation in categorical variables. While some methods currently exist for assessing spatial autocorrelation in categorical variables, the most popular method is unwieldy, somewhat ad hoc, and fails to provide grounds for a single omnibus test. Second, we discuss the importance of testing for autocorrelation in network, rather than spatial, data, motivated by applications in social network data. We demonstrate that existing tests for autocorrelation in spatial data for continuous variables and our new test for categorical variables can both be used in the network setting

Neck paraganglioma and follicular lymphoma: A case report

Background: Paragangliomas and pheochromocytomas are sympathetic or parasympathetic tumors derived from the paraganglia and the adrenal medulla, respectively. Paragangliomas and pheochromocytomas can be sporadic or familial, the latter frequently being multifocal and possibly due to succinate dehydrogenase complex genes mutations. In addition, 12% of sporadic paragangliomas are related to covered succinate dehydrogenase complex mutations. The importance of identifying succinate dehydrogenase complex mutations is related to the risk for these patients of developing multiple tumors, including non-endocrine ones, showing an aggressive clinical presentation. Case presentation: We report the case of a 45-year-old Caucasian man with an indolent mass in his neck. Ultrasound of his neck, magnetic resonance imaging, and 1,4,7,10-tetraazacyclododecane-N(I),N(II),N(III),N(IIII)-tetraacetic acid(D)-Phe(1)-thy(3)-octreotide (68Ga-DOTATOC) positron emission tomography-computed tomography and endocrine work-up were consistent with a carotid body paraganglioma with concomitant nodal enlargement in several body regions, which turned out to be a follicular lymphoma at histology. He was found to carry a germline Succinate dehydrogenase subunit B gene (SDHB) mutation. Conclusion: It is crucial to look for a second malignancy in the case of a paraganglioma demonstrating succinate dehydrogenase complex germline mutations