Rates of Short-GRB afterglows in association with Binary Neutron Star mergers

Assuming all binary Neutron Star mergers produce Short Gamma Ray Bursts (SGRBs), we combine the merger rates of binary Neutron Stars (BNS) from population synthesis studies, the sensitivities of advanced Gravitational Wave (GW) interferometer networks, and of the electromagnetic (EM) facilities in various wave bands, to compute the detection rate of associated afterglows in these bands. Using the inclination angle measured from GWs as a proxy for the viewing angle and assuming a uniform distribution of jet opening angle between 3 to 30 degrees, we generate light curves of the counterparts using the open access afterglow hydrodynamics package BoxFit for X-ray, Optical and Radio bands. For different EM detectors we obtain the fraction of EM counterparts detectable in these three bands by imposing appropriate detection thresholds. In association with BNS mergers detected by five (three) detector network of advanced GW interferometers, assuming a BNS merger rate of $0.6-774{\rm Gpc}^{-3}{\rm yr}^{-1}$~\citep{dominik2012double}, we find the afterglow detection rates (per year) to be $0.04-53$ ($0.02-27$), $0.03-36$ ($0.01-19$) and $0.04-47$ ($0.02-25$) in the X-ray, optical and radio bands respectively. Our rates represent maximum possible detections for the given BNS rate since we ignore effects of cadence and field of view in EM follow up observations.Comment: Published in MNRA

Exploring Short-GRB afterglow parameter space for observations in coincidence with gravitational waves

Short duration Gamma Ray Bursts(SGRB) and their afterglows are among the most promising electro-magnetic (EM) counterparts of Neutron Star (NS) mergers. The afterglow emission is broadband, visible across the entire electro-magnetic window from $\gamma$-ray to radio frequencies. The flux evolution in these frequencies is sensitive to the multi-dimensional afterglow physical parameter space. Observations of gravitational wave (GW) from BNS mergers in spatial and temporal coincidence with SGRB and associated afterglows can provide valuable constraints on afterglow physics. We run simulations of GW-detected BNS events and assuming all of them are associated with a GRB jet which also produces an afterglow, investigate how detections or non-detections in X-ray, optical and radio frequencies can be influenced by the parameter space. We narrow-down the regions of afterglow parameter space for a uniform top-hat jet model which would result in different detection scenarios. We list inferences which can be drawn on the physics of GRB afterglows from multi-messenger astronomy with coincident GW-EM observations.Comment: Published in MNRA

Performance studies of aerobic FBBR for the treatment of dairy wastewater

As the dairy wastewater produces lot of pollution problems, treatment of wastes before disposal becomes important. The endeavor to have a continuously operating, non clogging biofilm reactor with no need for backwashing, and high specific biofilm surface area culminated in the most advanced technology of Aerobic Fluidized Bed treatment where the biomass grows on small elements that move along with the water in the reactor. By the study, the FBB has been proved as highly efficient for strong dairy wastewater treatment. For an organic loading in the range 2.2 to 10.2 kg COD/m3d the efficiency variation was from 94.58 to 82.11%. The reactor combines all the advantages and best features of conventional treatment systems while eliminating the drawbacks of those

Pemberdayaan Perempuan melalui Daya Saing Produk Berbahan Ramah Lingkungan (Go Green) di USAha Pembuatan Tikar Daun Purun Palembang

Kota Palembang, sebagai ibu kota provinsi Sumatera Selatan terkenal sebagai pusat kuliner dan industri kerajinankhas Palembang. Industri tikar berbahan dasar daun purun merupakan USAha turun temurun dan menjadi USAha yangbanyak dilakukan oleh kaum perempuan terutama ibu-ibu yang memiliki kemampuan menganyam daun purunmenjadi produk tikar daun purun. Pemerintah Daerah berupaya untuk mempertahankan dan melestarikan USAha ini,melalui pemberian akses di bidang permodalan, pelatihan, pemasaran, mengikutsertakan pameran kerajinannusantara di Jakarta. Namun, USAha ini masih belum maksimal karena programm yang diberikan masih berjangkapendek, belum menyentuh akar sebenarnya yaitu masalah kemiskinan. Usaha ini juga, belum diorganisir denganbaik, dan belum dikelola secara profesional, padahal dari USAha ini secara tidak langsung sudah banyak memberikanmanfaat bagi pendapatan keluarga. Rumusan masalah adalah bagaimana memberdayakan kaum perempuan melaluipotensi-potensi yang dimilikinya, sehingga mampu membantu meningkatkan pendapatan keluarga. Penelitian inijuga untuk mengetahui kendala-kendala yang terjadi pada USAha pembuatan tikar daun purun ini, serta solusi yangdiperlukan dari temuan penelitian ini. Tujuan penelitian ini adalah untuk menggali potensi yang dimiliki kaumperempuan pengrajin, dan sekaligus pelaku USAha, menggali dan menggambarkan kendala-kendala kaum perempuandalam memanfaatkan bahan baku daun purun yang ramah lingkungan, serta solusi yang ditawarkan dari temuan ini.Metode yang digunakan adalah dengan metode forum diskusi kelompok dan wawancara. Hasil yang ditemukandalam penelitian ini antara lain; 1). Sebagian besar USAha tikar daun purun dilakukan oleh kaum perempuan, danmerupakan USAha turun temurun. Usaha ini mampu membantu pendapatan keluarga. 2). Kendala yang dihadapiadalah bahan baku daun purun yang jumlahnya semakin menurun karena adanya Perubahan fungsi lahan menjadiperkebunan sawit, dan musibah kebakaran yang kerap muncul setiap musim kemarau tiba, dan 3). Perlu adanyapembinaan yang optimal dari pihak pemerintah daerah, dan lembaga terkait dalam hal keuangan, pemasaran,pelatihan produk yang lebih variatif dan kompetitif serta menjadikan lokasi sekarang ini menjadi daerah sentra barupembuatan tikar daun purun yang berada di dalam kota Palembang

Amplitude death in complex networks induced by environment

We present a mechanism for amplitude death in coupled nonlinear dynamical systems on a complex network having interactions with a common environment-like external system. We develop a general stability analysis that is valid for any network topology and obtain the threshold values of coupling constants for the onset of amplitude death. An important outcome of our study is a universal relation between the critical coupling strength and the largest non-zero eigenvalue of the coupling matrix. Our results are fully supported by the detailed numerical analysis for different network topologies.Comment: 7 pages, 7 figure

Karakteristik Endapan Cairan Rumen Sapi Asal Rumah Potong Hewan Sebagai Feed Supplement

The aims of this experiment were to identify and characterize of sediment product from cattle rumen liquor as a source of amino acids, minerals and vitamins. The sediment were obtained as pellets upon centrifugation of rumen liquor at 10,000 g for 10 minutes for collection of supernatant. The sediment were evaluated for amino acids, minerals and vitamins composition and chararacterized for the pH, solubility of dry matter, specific density, bulk and compacted bulk densities and angle of response. Result of the experiment showed that sediment contained higher minerals: Na, K and Fe compared with the commercial premix, but lower in B-vitamins and amino acids. The composition of mineral Na, K, and Fe from rumen liquor of local cattle was 13.47%, 7.73 % and 14.52 %, while Na, K, and Fe from rumen liquor of imported cattle was 18.40%, 10.25%, and 14.52% respectively. The sediment had pH range from 10.01-10.03, the dry matter solubility was 35.5% up to 39.1%. The sediment from imported cattle had higher specific density, bulk and compacted bulk densities and angle of response than that of local cattle. It is concluded that sediment from cattle rumen liquor contained high Na, K and Fe, low amino acids and B-vitamin, high pH and low solubility

Antibacterial and wound healing efficacy of Chromolaena odorata treated dressings

78-86This paper reports the characteristics of viscose fabric treated with the extracts of Chromolaena odorata, traditionally used for healing the wounds. C. odorata extracts (5%) are nano-sprayed and applied on spun lace viscose fabric using an ultrasonic atomiser and antibacterial competence is optimised for S. aureus and E. coli. The wound healing potential of the C. odorata treated dressing and histopathological analysis of the wound tissues have been studied in vivo on Albino Wistar rats and compared with wound without any dressings, chitosan treated dressing, chitosan and C. odorata treated dressing along with the commercial silver bandage. The FTIR analysis of the phytochemicals finished fabric indicates the presence of phenolic group. Cytotoxicity test reveals 22% cytotoxicity and 78% cell viability with mild toxicity. Shelf life discloses the decrease in antibacterial efficiency after third and fourth week. Curing of C. odorata extracts treated fabric inversely affects the antibacterial efficiency, and sterilisation reports 46.7% E.coli reduction after one hour. The fabricated wound dressings are found to have good wound healing efficiency as compared to commercial silver bandage. The histopathological analysis reveals complete healing of wounds after 21 post wound healing days. The study proves that the phytochemicals can be imparted on spun lace viscose fabric for antibacterial and wound healing application to a certain period of time

Antibacterial and wound healing efficacy of Chromolaena odorata treated dressings

This paper reports the characteristics of viscose fabric treated with the extracts of Chromolaena odorata, traditionally used for healing the wounds. C. odorata extracts (5%) are nano-sprayed and applied on spun lace viscose fabric using an ultrasonic atomiser and antibacterial competence is optimised for S. aureus and E. coli. The wound healing potential of the C. odorata treated dressing and histopathological analysis of the wound tissues have been studied in vivo on Albino Wistar rats and compared with wound without any dressings, chitosan treated dressing, chitosan and C. odorata treated dressing along with the commercial silver bandage. The FTIR analysis of the phytochemicals finished fabric indicates the presence of phenolic group. Cytotoxicity test reveals 22% cytotoxicity and 78% cell viability with mild toxicity. Shelf life discloses the decrease in antibacterial efficiency after third and fourth week. Curing of C. odorata extracts treated fabric inversely affects the antibacterial efficiency, and sterilisation reports 46.7% E.coli reduction after one hour. The fabricated wound dressings are found to have good wound healing efficiency as compared to commercial silver bandage. The histopathological analysis reveals complete healing of wounds after 21 post wound healing days. The study proves that the phytochemicals can be imparted on spun lace viscose fabric for antibacterial and wound healing application to a certain period of time

Optical observations of the bright long duration peculiar GRB 021004 afterglow

The CCD magnitudes in Johnson $B,V$ and Cousins $R$ and $I$ photometric passbands are determined for the bright long duration GRB 021004 afterglow from 2002 October 4 to 16 starting $\sim$ 3 hours after the $\gamma-$ray burst. Light curves of the afterglow emission in $B$,$V$,$R$ and $I$ passbands are obtained by combining these measurements with other published data. The earliest optical emission appears to originate in a revese shock. Flux decay of the afterglow shows a very uncommon variation relative to other well-observed GRBs. Rapid light variations, especially during early times ($\Delta t < 2$ days) is superposed on an underlying broken power law decay typical of a jetted afterglow. The flux decay constants at early and late times derived from least square fits to the light curve are $0.99\pm0.05$ and $2.0\pm0.2$ respectively, with a jet break at around 7 day. Comparison with a standard fireball model indicates a total extinction of $E(B-V)=0.20$ mag in the direction of the burst. Our low-resolution spectra corrected for this extinction provide a spectral slope $\beta = 0.6\pm0.02$. This value and the flux decay constants agree well with the electron energy index $p\sim 2.27$ used in the model. The derived jet opening angle of about $7^{\circ}$ implies a total emitted gamma-ray energy $E_{\gamma} = 3.5\times10^{50}$ erg at a cosmological distance of about 20 Gpc. Multiwavelength observations indicate association of this GRB with a star forming region, supporting the case for collapsar origin of long duration GRBs.Comment: 19 pages, 3 figures, BASI, 31, 1