4,058 research outputs found

    Study of insulin resistance and antioxidant vitamin status in prostate cancer patients

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    The incidence of prostate cancer is 5 per 100000 in southern and eastern Asia. Both genetic and environmental factors have been implicated in its etiology. The mitogenic and growth stimulatory effects of Insulin growth factor may be involved in prostate carcinogenesis. To evaluate serum insulin and insulin resistance was passed by HOMA- IR. Prostatic specific antigen passed by immune-enzymatic assay. Vitamins were estimated by high performance liquid chromatography. In our study 30 prostate cancer patients aged 60-80years were taken as cases. 30 normal age matched disease free person were taken as controls in both groups, Insulin resistance and antioxidant vitamin status was studied.  In the present study, the value of HOMA-IR was (P <0.05) is significantly higher compare to controls. Serum vitamin E and vitamin C values for cases was reduced (P <0.05) significantly lower than controls. The development of prostate cancer is a multistep process. Hyperinsulinemia associated with insulin resistance may play a role in pathogenesis of prostate cancer. Prostate cancer cells generate high levels a ROS

    Simultaneous multi-frequency single pulse observations of pulsars

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    We performed simultaneous observations at 326.5 MHz with the Ooty Radio Telescope and at 326, 610 and 1308 MHz with the Giant Meterwave Radio Telescope for a sample of 12 pulsars, where frequency dependent single pulse behaviour was reported. The single pulse sequences were analysed with fluctuation analysis, sensitive to both the average fluctuation properties (using longitude resolved fluctuation spectrum and two-dimensional fluctuation spectrum) as well as temporal changes in these (using sliding two-dimensional fluctuation spectrum ) to establish concurrent changes in subpulse drifting over the multiple frequencies employed. We report subpulse drifting in PSR J0934−-5249 for the first time. We also report pulse nulling measurements in PSRs J0934−-5249, B1508+55, J1822−-2256, B1845−-19 and J1901−-0906 for the first time. Our measurements of subpulse drifting and pulse nulling for the rest of the pulsars are consistent with previously reported values. Contrary to previous belief, we find no evidence for a frequency dependent drift pattern in PSR B2016+28 implied by non-simultaneous observations by Oster et al. (1977). In PSRs B1237+25, J1822−-2256, J1901−-0906 and B2045−-16, our longer and more sensitive observations reveal multiple drift rates with distinct P3. We increase the sample of pulsars showing concurrent nulling across multiple frequencies by more than 100 percent, adding 4 more pulsars to this sample. Our results confirm and further strengthen the understanding that the subpulse drifting and pulse nulling are broadband consistent with previous studies (Gajjar et al. 2014a; Rankin 1986; Weltevrede et al. 2007) and are closely tied to physics of polar gap.Comment: 22 pages, 44 figures, Single pulse studies of pulsars, accepted by A&

    PONDER - A Real time software backend for pulsar and IPS observations at the Ooty Radio Telescope

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    This paper describes a new real-time versatile backend, the Pulsar Ooty Radio Telescope New Digital Efficient Receiver (PONDER), which has been designed to operate along with the legacy analog system of the Ooty Radio Telescope (ORT). PONDER makes use of the current state of the art computing hardware, a Graphical Processing Unit (GPU) and sufficiently large disk storage to support high time resolution real-time data of pulsar observations, obtained by coherent dedispersion over a bandpass of 16 MHz. Four different modes for pulsar observations are implemented in PONDER to provide standard reduced data products, such as time-stamped integrated profiles and dedispersed time series, allowing faster avenues to scientific results for a variety of pulsar studies. Additionally, PONDER also supports general modes of interplanetary scintillation (IPS) measurements and very long baseline interferometry data recording. The IPS mode yields a single polarisation correlated time series of solar wind scintillation over a bandwidth of about four times larger (16 MHz) than that of the legacy system as well as its fluctuation spectrum with high temporal and frequency resolutions. The key point is that all the above modes operate in real time. This paper presents the design aspects of PONDER and outlines the design methodology for future similar backends. It also explains the principal operations of PONDER, illustrates its capabilities for a variety of pulsar and IPS observations and demonstrates its usefulness for a variety of astrophysical studies using the high sensitivity of the ORT.Comment: 25 pages, 14 figures, Accepted by Experimental Astronom
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