Development of a metalised carbon fiber reinforced plastic (CFRP) antenna reflector for satellite communication

The Antenna reflectors made of Carbon Fibre Reinforced Plastics (CFRP) are used in spacecrafts for Satellite Communication in C, S and Ku bands. For futuristic Satellite Communication applications in x2018;Kax2019; band, there is a need of improving the reflectivity for Radio Frequency (RF) signals by metallising the surface of CFRP reflectors. The space qualified CFRP reflectors have been developed by ISRO for various GEOSAT projects but the process for developing a space qualified reflector having a metallized surface has not been established in the country. Recently, efforts in this hither to fore unexplored domain have been made jointly by Space Application Center, Ahemadabad and National Aerospace lab, Bangalore to develop reflectors with metallized surface

MODULATION AWARE CONNECTION ADMISSION CONTROL AND UPLINK SCHEDULING ALGORITHM FOR WIMAX NETWORKS

Mobile WiMAX standard defines air interface for mobile broadband wireless access (BWA) systems and aimed to provide high data rate with seamless mobility while maintaining the quality of service (QoS). However, QoS of real-time applications depends on the link quality, which necessitate the channel-aware connection admission control (CAC) and scheduling schemes. In this paper Modulation aware CAC scheme and base station (BS) uplink scheduling algorithm are proposed to improve the system capacity and QoS performance respectively. The proposed CAC scheme aims to increase the admission of higher priority real time services by degrading the bandwidth of admitted lower priority connections on the basis of their channel status without deteriorating their QoS performance much. The performances of proposed algorithms are evaluated through simulation by considering the metrics like throughput, delay and number of connections admitted

Hadron energy response of the Iron Calorimeter detector at the India-based Neutrino Observatory

The results of a Monte Carlo simulation study of the hadron energy response for the magnetized Iron CALorimeter detector, ICAL, proposed to be located at the India-based Neutrino Observatory (INO) is presented. Using a GEANT4 modeling of the detector ICAL, interactions of atmospheric neutrinos with target nuclei are simulated. The detector response to hadrons propagating through it is investigated using the hadron hit multiplicity in the active detector elements. The detector response to charged pions of fixed energy is studied first, followed by the average response to the hadrons produced in atmospheric neutrino interactions using events simulated with the NUANCE event generator. The shape of the hit distribution is observed to fit the Vavilov distribution, which reduces to a Gaussian at high energies. In terms of the parameters of this distribution, we present the hadron energy resolution as a function of hadron energy, and the calibration of hadron energy as a function of the hit multiplicity. The energy resolution for hadrons is found to be in the range 85% (for 1GeV) -- 36% (for 15 GeV).Comment: 14 pages, 10 figures (24 eps files

Kikuchi-Fujimoto disease presenting as pyrexia of unknown origin

Background: Kikuchi-Fujimoto disease, a benign self-limited lymphadenopathy is an uncommon cause of pyrexia of unknown origin (PUO). Methods: We retrospectively studied the case-records of 13 patients presenting with PUO who were diagnosed to have Kikuchi-Fujimoto disease on peripheral lymph node excision biopsy and report the salient clinical manifestations and histopathological findings in them. All of them received symptomatic treatment. Results: Their median age was 28 [interquartile range (IQR) 18.5-38.0] years. Women (11/13, 84.6%) were more frequently affected. All of them were human immunodeficiency virus (HIV) seronegative. Prior to presenting to us, two were being treated for lymph node tuberculosis with DOTS. Cervical lymph nodes were predominantly involved, the distribution being: right cervical (n=10, 76.9%); left cervical (n=4); and bilateral cervical (n=2). Axillary and generalized lymphadenopathy were rare being seen in 2 and 1 patient respectively. The median (IQR) erythrocyte sedimentation rate (n=11) was 53 (35-89) mm at the end of first hour. Salient histopathological features were paracortical patchy zones of eosinophilic fibrinoid necrosis with karyorrhectic debris, large numbers of histiocytes, including histiocytes with peripherally placed “crescentic” nuclei. Spontaneous regression of fever and lymphadenopathy was observed over a median (IQR) period of 8 (6.75-10.25) months in all of them. Conclusions: Kikuchi-Fujimoto disease is a rare but important cause of PUO presenting with peripheral lymphadenopathy. Women are most often affected and cervical lymph nodes are the most frequently involved site. Clinical suspicion and thoughtful collaboration between clinicians and pathologists are essential for accurate diagnosis, and to minimize unnecessary investigations and inappropriate aggressive treatment

Mapping giant magnetic fields around dense solid plasmas by high resolution magneto-optical microscopy

We investigate distribution of magnetic fields around dense solid plasmas generated by intense p-polarized laser (~10^{16} W.cm^{-2}, 100 fs) irradiation of magnetic tapes, using high sensitivity magneto optical microscopy. We present evidence for giant axial magnetic fields and map out for the first time the spatial distribution of these fields. By using the axial magnetic field distribution as a diagnostic tool we uncover evidence for angular momentum associated with the plasma. We believe this study holds significance for investigating the process under which a magnetic material magnetizes or demagnetizes under the influence of ultrashort intense laser pulses.Comment: 17 pages of text with 4 figure

Soil Carbon in Agroforestry Systems: An Unexplored Treasure?

Soil organic matter (SOM), which contains more reactive organic carbon (C) than any other single terrestrial pool, plays a major role in determining C storage in ecosystems and regulating atmospheric concentrations of carbon dioxide (CO2)^1^. Agroforestry, the practice of growing trees and crops in interacting combinations on the same unit of land^2^, primarily by resource-poor smallholder farmers in developing countries, is recognized as a strategy for soil carbon sequestration (SCS) under the Clean Development Mechanism (CDM) of the Kyoto Protocol^3^. The understanding about C storage and dynamics under agroforestry systems (AFS), however, is minimal. Our studies under various AFS in diverse ecological conditions in five countries showed that tree-based agricultural systems, compared to treeless systems, stored more C in deeper soil layers up to 1 m depth under comparable conditions. More C is stored in soil near the tree than away from the tree; higher SOC content is associated with higher species richness and tree density; and C3 plants (trees) contribute to more C in the silt- + clay-sized (<53 µm) fractions that constitute more stable C, than C4 plants, in deeper soil profiles4 - 8. These results provide clear indications of the possibilities for climate change mitigation through SCS in AFS, and opportunities for economic benefit - through carbon trading - to millions of smallholder farmers in developing countries

A Pharmaceutical Study of an Ayurvedic Formulation - Balyadi Lepa

Balyadi lepa is a herbo-mineral formulation mentioned in the classical text called Yogaratnakara. It contains Shuddha Gandhaka, Shuddha Bhallataka, Shuddha Chitraka, Danti, Nimba, Vidanga, and Amlavetasa. Balyadi lepa is useful in the management of Switra. Balyadi lepa should be mixed with lukewarm water and applied on the affected area. Shodhana of Gandhaka is explained in Rasa Ratna Samucchaya, Shodana of Bhallataka and Chitraka is explained in Rasa Tarangin, preparation of Churna is explained in the Sharangadhara samhitha. In the present study, Churna of all drugs were taken in a Khalwa yantra and mixed well to prepare homogenous mixture of Balyadi lepa. Step by step pharmaceutical procedures were carried out according to classical reference and SOP. Loss during the process, total yield is noted. Pharmacological action of the Balyadi lepa is discussed in brief

FORMULATION AND EVALUATION OF FAST DISSOLVING TABLETS OF RANITIDINE HYDROCHLORIDE BY HOLE TECHNOLOGY

Attempts were made to prepare ranitidine fast dissolving tablets by Novel Hole technology. When these fast dissolving tablets contact with gastro intestinal fluids, the fluid will enters the hole present in the tablet and immediate breaking of the tablet is going to takes place. This fast disintegration of tablets is also influenced by the formation of new absolute area. The prepared FDTs were subjected to various pre and post formulation studies. Its disintegration and dissolution rates were compared with the control formulation (without hole).In-vitro drug release of FDTs (DH6) showed almost 100.92percent of the drug was released at 6th minute, whereas the control formulation D12, shows the 99percent drug release at 20th minute. Overall, this technique is novel and most useful for formulation into fast dissolving tablets.Key words: Novel Fast Dissolving Tablets, Ranitidine, Hole technolog