भारत की महाचिंगट मात्स्यिकी संपदाएं

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Status and management of lobster fishery resources in India

In India, though lobsters form only 0.12 ± 0.06% of total marine landings, they form an important export product comprising 1.07 ± 0.44% in quantity and 2.59 ± 1.15% in value. Total annual landings have been fluctuating between 1587 to 2917 tonnes for the past fifteen years (1985-2000) with the highest landing of 4075 tonnes in 1985 (Fig.l)

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On the Excess Dispersion in the Polarization Position Angle of Pulsar Radio Emission

The polarization position angles (PA) of pulsar radio emission occupy a distribution that can be much wider than what is expected from the average linear polarization and the off-pulse instrumental noise. Contrary to our limited understanding of the emission mechanism, the excess dispersion in PA implies that pulsar PAs vary in a random fashion. An eigenvalue analysis of the measured Stokes parameters is developed to determine the origin of the excess PA dispersion. The analysis is applied to sensitive, well-calibrated polarization observations of PSR B1929+10 and PSR B2020+28. The analysis clarifies the origin of polarization fluctuations in the emission and reveals that the excess PA dispersion is caused by the isotropic inflation of the data point cluster formed by the measured Stokes parameters. The inflation of the cluster is not consistent with random fluctuations in PA, as might be expected from random changes in the orientation of the magnetic field lines in the emission region or from stochastic Faraday rotation in either the pulsar magnetosphere or the interstellar medium. The inflation of the cluster, and thus the excess PA dispersion, is attributed to randomly polarized radiation in the received pulsar signal. The analysis also indicates that orthogonal polarization modes (OPM) occur where the radio emission is heavily modulated. In fact, OPM may only occur where the modulation index exceeds a critical value of about 0.3.Comment: Accepted for publication in Ap

കേരളത്തിലെ കംകിടി വര്ഗ്ഗ സമ്പത്തും ജലകൃഷിരംഗത്ത് വനിതാശാക്തീകരണസാദ്ധ്യതയും

Training Material for Post Harvest handling of Shrimp and Clam Product

तमिलनाडु-पोण्डिचेरी तट की तारली मात्स्यिकी-हाल की विदोहन प्रवणता और कुछ जैविक सूचनाऐं

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Recent exploitation trend of oil sardine along Tamil nadu - Pondicherry coast

The Indian oil sardine SardineUa lorgiceps.though a non-conventional resource of the east coast, supports now a regular fishery of high magnitude especially along Andhra Pradesh and TanJl Nadu - Pondicheny coasts. The estimated annual average landing from east coast during the period 1993-97 was 60.638 tonnes against 46.000 t obtained along west coast thereby showing the potential of this new resource, especially along the southern maritime states of the east coast. It has been observed that the oil sardine catch during 1993-97 increased to more than three fold in Andhra Pradesh from that of the previous five year period 1988-92 while along Tamil Nadu - Pondicheny coast the catch almost doubled and recorded 80% of the total oil sardine production of east coast

Predictors of angiographic restenosis in patients with coronary artery disease who have undergone percutaneous coronary intervention with drug eluting stents

Background: Percutaneous transluminal coronary angioplasty (PTCA) is now widely accepted as a nonsurgical revascularization procedure for selected patients with CAD. In-stent restenosis (ISR) is a frequent complication after PCI which limits its long-term efficacy. Identification of those clinical and angiographic characteristics that may predict the risk of restenosis is extremely important to eliminate restenosis. In this context we conducted this study to assess the profile of patients with drug eluting stents - ISR with an emphasis on demographic characteristics, risk factors, mode of presentation and coronary angiographic characterization.Methods: This study was a Case control study based on the catheterization registry of all patients who have undergone PCI with DES during the period from October 2012 to April 2015. All patients who have undergone PCI with DES and repeat coronary angiogram for evaluation of symptoms and detected to have ISR during same period were taken as case and age matched patients who had previously undergone PCI with DES and repeat coronary angiogram for evaluation of symptoms between 1/10/2012 to 30/4/2015 and detected to have fully patent stents were taken as control.Results: A total of 26 patients were detected to have ISR during the study period as per the study protocol with equal number of age matched controls. The most common presentation of ISR was as chronic stable angina (70%). Binary logistic regression analysis of 6 factors namely diabetes, hypertension, lesion type, stent diameter, stent length and stent overlap found significant in univariate analysis, showed only the lesion type to be statistically significant with p value of 0.023.Conclusions: Patients who have undergone PCI with DES particularly for complex lesions, diabetics with longer stents, lesser diameter stents and overlapping stents need to be meticulously followed up to rule out the possibility of restenosis, as in a small number of patients the presentation could be ACS with comparatively bad prognosis

The ASCA Spectrum of the Vela Pulsar Jet

ROSAT observations of the Vela pulsar and its surroundings revealed a collimated X-ray feature almost 45' in length (Markwardt & Ogelman 1995), interpreted as the signature ``cocoon'' of a one-sided jet from the Vela pulsar. We report on a new ASCA observation of the Vela pulsar jet at its head, the point where the jet is believed to interact with the supernova remnant. The head is clearly detected, and its X-ray spectrum is remarkably similar to the surrounding supernova remnant spectrum, extending to X-ray energies of at least 7 keV. A ROSAT+ASCA spectrum can be fit by two-component emission models but not standard one-component models. The lower energy component is thermal and has a temperature of 0.29+/-0.03 keV (1 sigma); the higher energy component can be fit by either a thermal component of temperature ~4 keV or a power law with photon index ~2.0. Compared to the ROSAT-only results, the mechanical properties of the jet and its cocoon do not change much. If the observed spectrum is that of a hot jet cocoon, then the speed of the jet is at least 800 km s^-1, depending on the angle of inclination. The mechanical power driving the jet is >10^36 erg s^-1, and the mass flow rate at the head is > 10^-6 M_sun yr^-1. We conclude that the jet must be entraining material all along its length in order to generate such a large mass flow rate. We also explore the possibility that the cocoon emission is synchrotron radiation instead of thermal.Comment: 12 pages, LaTeX in AAS v4.0 preprint style, two PS figures, accepted for publication in the ApJ Letter

Mechanical Failure Analysis of Needles, for Micro-needle Array Dry-electrodes

 Dry electrodes, which have an array of vertically aligned conducting micro-needles over a conducting substrate/base are most suitable for long-term continuous monitoring of EEG-signal, and overcomesthe disadvantages of conventional wet electrodes. A crucial design requirement for thesemicro-needlearrays, is the choice of the needle material with suitable mechanical strength to penetrate the skin without mechanical failure. This paper gives, the results of mechanical failure analysis of different needle materials that have been typically used/proposed for invasive use. A conical needle with 150μ width at the base and 10μ width at the tip, and length in the range 10μ - 200μ was taken up for calculation. The Critical load for failure, falls in the following descending order for the selected materials: viz., Carbon Nanofibre (CNF), Titanium-alloy (Ti 6-4), Single Crystal Silicon, Nickel, Tungsten, Platinum-Iridium (Pt90 percent-Ir10 percent), Stainless Steel (SS304),Poly Methyl Methacrylate (PMMA), Polyimide, Polycarbonate, Gold, Silver, Photoresist-SU8, Polyurethane and Poly DiMethylSiloxane (PDMS).Taking the most accepted value of 0.1N as the penetration force required for needle penetration into skin, it is seen that for a needle length of 100μ, the following materials, Carbon Nanofibre (CNF), Titanium-alloy (Ti 6-4), Single Crystal Silicon, Nickel, Tungsten, Platinum -Iridium (Pt90 percent-Ir10 percent) andStainless Steel (SS304), can penetrate the skin without mechanical failure