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We present experimental results of the trace argon impurity puffing in the ohmic plasmas of Aditya-U tokamak performed to study the argon transport behaviour. Argon line emissions in visible and Vacuum Ultra Violet (VUV) spectral ranges arising from the plasma edge and core respectively are measured simultaneously. During the experiments, space resolved brightness profile of Ar1+ line emissions at 472.69 nm (3p44s 2P3/2–3p44p 2D3/2), 473.59 nm (3p44s 4P5/2–3p44p 4P3/2), 476.49 nm (3p44s 2P1/2–3p44p 2P3/2), 480.60 nm (3p44s 4P5/2–3p44p 4P5/2) are recorded using a high resolution visible spectrometer. Also, a VUV spectrometer has been used to simultaneously observe Ar13+ line emission at 18.79 nm (2s22p 2P3/2–2s2p22P3/2) and Ar14+ line emission at 22.11 nm (2s21S0–2s2p 1P1). The diffusivity and convective velocity of Ar are obtained by comparing the measured radial emissivity profile of Ar1+ emission and the line intensity ratio of Ar13+ and Ar14+ ions, with those simulated using the impurity transport code, STRAHL. Argon diffusivities ~ 12 m2/s and ~ 0.3 m2/s have been observed in the edge (ρ > 0.85) and core region of the Aditya-U, respectively. The diffusivity values both in the edge and core region are found to be higher than the neo-classical values suggesting that the argon impurity transport is mainly anomalous in the Aditya-U tokamak. Also, an inward pinch of ~ 10 m/s mainly driven by Ware pinch is required to match the measured and simulated data. The measured peaked profile of Ar density suggests impurity accumulation in these discharges. [ABSTRACT FROM AUTHOR]

With its large effective area at hard X-rays, high time resolution and having co-aligned other instruments, AstroSat/LAXPC was designed to usher in a new era in rapid variability studies and wide spectral band measurements of the X-ray binaries. Over the last five years, the instrument has successfully achieved to a significant extent these Science goals. In the coming years, it is poised to make more important discoveries. This paper highlights the primary achievements of AstroSat/LAXPC in unraveling the behavior of black hole and neutron star systems and discusses the exciting possibility of the instrument's contribution to future science. [ABSTRACT FROM AUTHOR]

The Large Area X-ray Proportional Counter (LAXPC) instrument on-board AstroSat has three nominally identical detectors for timing and spectral studies in the energy range of 3–80 keV. The performance of these detectors during the five years after the launch of AstroSat is described. Currently, only one of the detector is working nominally. The variation in pressure, energy resolution, gain and background with time are discussed. The capabilities and limitations of the instrument are described. A brief account of available analysis software is also provided. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Role of pinch in Argon impurity transport in ohmic discharges of Aditya-U Tokamak" published in Scientific Reports. The correction addresses an error in Figure 9 of the original PDF version, where the radial profiles were incorrectly displayed. The correction has been made to the PDF version of the article, while the HTML version was correct at the time of publication. The article was authored by K. Shah, J. Ghosh, S. Patel, M. B. Chowdhuri, K. A. Jadeja, G. Shukla, T. Macwan, A. Kumar, S. Dolui, K. Singh, R. L. Tanna, K. M. Patel, R. Dey, R. Manchanda, N. Ramaiya, R. Kumar, S. Aich, N. Yadava, S. Purohit, M. K. Gupta, U. C. Nagora, S. K. Pathak, P. K. Atrey, and K. B. K. Mayya. [Extracted from the article]

Large area X-ray propositional counter (LAXPC) instrument on AstroSat is aimed at providing high time resolution X-ray observations in 3-80 keV energy band with moderate energy resolution. To achieve large collecting area, a cluster of three co-aligned identical LAXPC detectors, is used to realize an effective area in access of $${\sim }6000\,\hbox {cm}^{2}$$ at 15 keV. The large detection volume of the LAXPC detectors, filled with xenon gas at $${\sim }$$ 2 atmosphere pressure, results in detection efficiency greater than 50%, above 30 keV. In this article, we present salient features of the LAXPC detectors, their testing and characterization in the laboratory prior to launch and calibration in the orbit. Some preliminary results on timing and spectral characteristics of a few X-ray binaries and other type of sources, are briefly discussed to demonstrate that the LAXPC instrument is performing as planned in the orbit. [ABSTRACT FROM AUTHOR]

ASTROSAT is India's first satellite fully devoted to astronomical observations covering a wide spectral band from optical to hard X-rays by a complement of 4 co-aligned instruments and a Scanning Sky X-ray Monitor. One of the instruments is Large Area X-ray Proportional Counter with 3 identical detectors. In order to assess the performance of this instrument, a balloon experiment with two prototype Large Area X-ray Proportional Counters (LAXPC) was carried out on 2008 April 14. The design of these LAXPCs was similar to those on the ASTROSAT except that their field of view (FOV) was 3 × 3 versus FOV of 1 × 1 for the LAXPCs on the ASTROSAT. The LAXPCs are aimed at the timing and spectral studies of X-ray sources in 3-80 keV region. In the balloon experiment, the LAXPC, associated electronics and support systems were mounted on an oriented platform which could be pre-programmed to track any source in the sky. A brief description of the LAXPC design, laboratory tests, calibration and the detector characteristics is presented here. The details of the experiment and background counting rates of the 2 LAXPCs at the float altitude of about 41 km are presented in different energy bands. The bright black hole X-ray binary Cygnus X-1 (Cyg X-1) was observed in the experiment for ∼ 3 hours. Details of Cyg X-1 observations, count rates measured from it in different energy intervals and the intensity variations of Cyg X-1 detected during the observations are presented and briefly discussed. [ABSTRACT FROM AUTHOR]

In this paper, a laboratory-based penning plasma discharge source is reported which has been developed in two anode configurations and is able to produce visible and VUV lights simultaneously. The developed source has simultaneous diagnostics facility using Langmuir probe and optical emission spectroscopy. The two anode configurations, namely, double ring and rectangular configurations, have been studied and compared for optimum use of the geometry for efficient light emissions and recording. The plasma is produced using helium gas and admixture of three noble gases including helium, neon, and argon. The source is capable to produce eight spectral lines for pure helium in the VUV range from 20 to 60 nm and total 24 spectral lines covering the wavelength range 20-106 nm for the admixture of gases. The large range of VUV lines is generated from gaseous admixture rather from the sputtered materials. The recorded spectrum shows that the plasma light radiations in both visible and VUV range are larger in double ring configuration than that of the rectangular configurations at the same discharge operating conditions. To clearly understand the difference, the imaging of the discharge using ICCD camera and particle-in-cell simulation using VORPAL have also been carried out. The effect of ion diffusion, metastable collision with the anode wall and the nonlinear effects are correlated to explain the results. [ABSTRACT FROM AUTHOR]

Background:There are limited data on surgical outcomes in gynaecological oncology. We report on predictors of complications in a multicentre prospective study.Methods:Data on surgical procedures and resulting complications were contemporaneously recorded on consented patients in 10 participating UK gynaecological cancer centres. Patients were sent follow-up letters to capture any further complications. Post-operative (Post-op) complications were graded (I-V) in increasing severity using the Clavien-Dindo system. Grade I complications were excluded from the analysis. Univariable and multivariable regression was used to identify predictors of complications using all surgery for intra-operative (Intra-op) and only those with both hospital and patient-reported data for Post-op complications.Results:Prospective data were available on 2948 major operations undertaken between April 2010 and February 2012. Median age was 62 years, with 35% obese and 20.4% ASA grade ⩾3. Consultant gynaecological oncologists performed 74.3% of operations. Intra-op complications were reported in 139 of 2948 and Grade II-V Post-op complications in 379 of 1462 surgeries. The predictors of risk were different for Intra-op and Post-op complications. For Intra-op complications, previous abdominal surgery, metabolic/endocrine disorders (excluding diabetes), surgical complexity and final diagnosis were significant in univariable and multivariable regression (P<0.05), with diabetes only in multivariable regression (P=0.006). For Post-op complications, age, comorbidity status, diabetes, surgical approach, duration of surgery, and final diagnosis were significant in both univariable and multivariable regression (P<0.05).Conclusions:This multicentre prospective audit benchmarks the considerable morbidity associated with gynaecological oncology surgery. There are significant patient and surgical factors that influence this risk. [ABSTRACT FROM AUTHOR]

Background:In research studies, accurate information of cancer diagnosis is crucial. In women with breast cancer (BC), we compare cancer registration (CR) in England/Wales and self-reporting with independent confirmation.Methods:In the UK Collaborative Trial of Ovarian Cancer Screening, notification of BC diagnosed between randomisation and 31 December 2009 was obtained through (1) CR (17 October 2011) and (2) self-reporting using postal-questionnaire. Breast cancer was confirmed using a detailed questionnaire (BC questionnaire BCQ) completed by the treating clinician (gold standard). Apparent sensitivity and positive-predictive value of CR/self-reporting vs BCQ were calculated.Results:Of 1065 women with possible BC notification, diagnosis was confirmed in 932 (87.5%). A total of 3.1% (28 out of 918) of BC CR and 12.4% (128 out of 1032) of women with self-reported BC only had in-situ carcinoma on BCQ. Another 4.6% (43 out of 932) of BCQ-confirmed cancer did not have a BC registration, and 3.6% (34 out of 932) did not self-report BC. Apparent sensitivity of CR and self-reporting vs BCQ were 95.4 and 96.4%, respectively. Positive-predictive value of self-reporting (87.1%) was significantly lower than that of CR (96.8%). Women aged<65 were more likely to over report in-situ carcinoma as BC. Overall, 73 (6.8%) women would have been misclassified/missed if CR, and 167 (15.6%) if self-reporting data alone was used.Conclusion:This study confirms the reliability of BC registration in England/Wales and highlights the fact that 1 in 10 women self-reporting BC might only have in-situ breast carcinoma. [ABSTRACT FROM AUTHOR]

The purpose of this study is to measure the impact of a multidisciplinary one-stop follow-up clinic (MDOSC) on breast and ovarian surveillance, risk reducing surgery and enrolment in clinical trials in BRCA1/2 carriers. All BRCA1/2 carriers in our region were invited and chose which specialists to see in our MDOSC offering best practice using clinical protocols based on national guidelines and published data. Uptake was evaluated over 24 months recording numbers of individuals undergoing breast and ovarian surveillance, risk reducing surgery, newly diagnosed cancers, their method of detection and participation in clinical trials. 172 (60%) of invited BRCA1/2 carriers chose to attend the MDOSC. Breast surveillance was initiated in 88% and screening frequency altered in 14% of women to comply with national guidelines. Risk reducing salpingo-oophorectomy was chosen by 47% of women and an additional 39% were considering it. The rate of failure to remove fallopian tubes fell from 15 to 3% of procedures ( P < 0.01) and peritoneal washings and serial sectioning of tubes and ovaries rose from 25% and 14% before, to 67% ( P < 0.001) and 63% ( P < 0.001) procedures, respectively, after initiation of our MDOSC. 24% of women considered and 18% decided to undergo risk reducing mastectomy during the follow-up period. Participation in clinical trials increased significantly from 51 to 229 enrolments ( P < 0.001). Our novel MDOSC designed to devise an individually tailored cancer risk management strategy had a high uptake amongst our BRCA1/2 carriers. Attendance resulted in improved breast and ovarian cancer risk management. [ABSTRACT FROM AUTHOR]

A building block-based software framework was developed to simulate electrophysiological networks. The synaptic potentials generated during neurotransmission were simulated in an existing discrete bidomain model of smooth muscle, using cubic, three-dimensional grids of varying sizes. The model is automatically derived and numerically solved, and the results of the simulation agree with previous results obtained analytically. An enhanced model was also proposed, incorporating an additional (junctional) capacitance in the network. The correctness of the model was verified, and the effect of the extra capacitance on the synaptic potentials was explored. It was found that, with a junctional capacitance C(i) of 1.4 x 10(-10) F incorporated, the peak amplitude of the spontaneous excitatory junction potential V(peak) declined by approximately 13% at node 0 and by approximately 37% at node 3x for a system size of 9(3). Similar results were obtained for different system sizes. V(peak) also declined as the junctional capacitance Ci was increased. In a system of size 11(30, a 200-fold increase in C(i) induced a 55% reduction at node 0. It is suggested that the type of modular simulation framework developed here may find general applicability for simulations of other physiological systems. [ABSTRACT FROM AUTHOR]

The effect of the size of syncytial bundles of cells on the passive synaptic potentials generated within them has been explored. Computer simulations have been performed of neuronally produced spontaneous excitatory junction potentials (SEJPs) generated in cubical 'bidomain' model of syncytial tissue. It is found that indical properties of SEJPs vary conspicuously in syncytium sizes smaller than about 15-17-cube, but change very little in syncytium sizes greater than this. At the centroid of the cube, the peak amplitude Vp of the SEJP declines from 14.32 mV to 11.70 mV as syncytium size increases from 7-cube to 15-cube, i.e. a decrease of approximately 18%, while between system sizes 15-cube (Vp = 11.70 mV) and 29-cube (Vp = 11.67 mV), the reduction is only approximately 0.3%. Similar trends are observed for the time to peak of SEJPs. These observations indicate a minimum bundle size in smooth muscle below which syncytial function is modified; the implications of this are discussed. [ABSTRACT FROM AUTHOR]

An hard X-Rays (15-170) KeV measurement of the spectrum of Her X-1, during a mid turn on is presented. The presence of an emission line at about 53 KeV during the mid-on state is confirmed by the present measure. [ABSTRACT FROM AUTHOR]

A 45-day-old infant presented with hepatosplenomegaly and fever since 15 days. Hemogram revealed bicytopenia and bone marrow aspirate showed hemophagocytosis. With the history of death of two siblings, the baby was diagnosed with hemophagocytic lymphohistiocytosis (HLH), likely to be of familial origin. [ABSTRACT FROM AUTHOR]

Cryptococcosis is caused by cryptococcus neoformans. Immunosuppression is a predisposing factor for the development of cryptococcosis. However, reports exist that cryptococcus neoformans can cause infection in immunocompetent hosts. We report a case of disseminated cryptococcosis in a 7.5-year-old immunocompetent child. [ABSTRACT FROM AUTHOR]

Vaginal rupture leading to pneumoperitoneum is well documented to occur after hysterectomy or surgery. However, it is extremely rare in a young woman following conventional intercourse. We report one such case. A 16-year-old woman presented to the accident and emergency department with a clinical picture of an acute abdomen. Results of radiography showed gas under the diaphragm, suggesting the possibility of bowel perforation. A detailed sexual history pointed toward the possibility of vaginal trauma. Diagnosis was confirmed on examination under anesthesia, and the tear repaired. A concomitant laparoscopy ruled out any other intra-abdominal injury. This case reminds us that acute peritoneum can occur after sexual intercourse and also reiterates the importance of a detailed sexual history and vaginal examination in young women presenting with an acute abdomen. [ABSTRACT FROM AUTHOR]