Informatics Publishing Limited

S. Sreekumar ¹

Affiliations
1 Department of Geology and Environmental Sciences, Christ College, Irinjalakuda - 680 125, IN

Abstract

The occurrences of slope failures are frequent in Idukki district of Kerala state particularly along the road cuttings and hill slopes causing disruption in traffic, loss of lives and property. This demands a critical evaluation of stability of slopes along the hill roads. This paper deals with stability analysis of a typical hard rock profile at Chuzhappu and a lateritic profile at Kumili along the road connecting Kottayam and Kumili. A large number of factors have been examined and studied; the orientation of discontinuities has been identified as one of the major inherent factors influencing slope instability along Chuzhappu hard rock profile. These have been analysed carefully using stereographic/equal area projection technique in order to determine the vulnerability to slope failure and to understand the type of rock slide that can occur in this profile. The buoyant force of water acting along the discontinuities after heavy rain storm further aids the down slope movement. As the laterite slope is mostly homogeneous, Bishops method and Swedish method were adopted for stability analysis of laterite slope at Kumili. The study also examines the efficacy and applicability of the different methods employed in soil mechanics to assess the stability of laterite slope. The results obtained by this method are compared by actual field conditions. The stability assessment indicates that two sectors at Chuzhappu and one sector at Kumili profile are at the geo-technical threshold of failure, when piezometric head rises during rainstorm. The study indicates that these methods are highly useful in determining the Factor of Safety in profiles with similar geological setting.

Keywords

Factor of Safety, Stereographic Projections, Slope Stability, Wedge Failure, Kerala.

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M. Kadeeja Beevi ¹, S. Sreekumar ¹, K. Hiran Nazir ¹

Affiliations
1 Department of Geology and Environmental Science, Christ College, Irinjalakuda-680 125, Kerala, IN

Abstract

The backwater of Kerala is becoming polluted due to persistent retting of coconut husk for the manufacture of coir. This paper assesses the ecological status of the retting ground and brings out the occupational health hazards due to coir retting. It is observed that the quality of water becomes deteriorated due to retting, and plankton and benthic fauna show low community diversity. The paper also highlights the occupational health hazards observed among the coir workers.

Keywords

Kayamkulam Backwaters, Coir Retting, Biodiversity, Health Hazards.

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A. R. Rao ¹, D. Bhattacharya ², V. B. Bhalerao ², S. V. Vadawale ³, S. Sreekumar ⁴

Affiliations
1 Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, IN
2 Inter-University Centre for Astronomy and Astrophysics, Pune 411 007, IN
3 Physical Research Laboratory, Ahmedabad 380 009, IN
4 Vikram Sarabhai Space Centre, Thiruvananthapuram 695 024, IN

Abstract

The AstroSat satellite is designed to make multi-waveband observations of astronomical sources and the Cadmium-Zinc-Telluride Imager (CZTI) instrument of AstroSat covers the hard X-ray band. CZTI has a large area position-sensitive hard X-ray detector equipped with a coded aperture mask, thus enabling simultaneous background measurements. Ability to record simultaneous detection of ionizing interactions in multiple detector elements is a special feature of the instrument, and this is exploited to provide polarization information in the 100-380 keV region. CZTI provides sensitive spectroscopic measurements in the 20-100 keV region, and acts as an all-sky hard X-ray monitor and polarimeter above 100 keV. During the first year of operation, CZTI has recorded several gamma-ray bursts, measured the phase-resolved hard X-ray polarization of the Crab pulsar, and the hard X-ray spectra of many bright galactic X-ray binaries. The excellent timing capability of the instrument has been demonstrated with simultaneous observation of the Crab pulsar with radio telescopes like Gaint Metrewave Radio Telescope and Ooty Radio Telescope.

Keywords

All-Sky Hard X-Ray Monitor, Gamma-Ray Bursts, Neutron Stars, X-Ray Polarization.

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N. C. Nisha ¹, S. Sreekumar ¹, D. A. Evans ², C. K. Biju ¹

Affiliations
1 Saraswathy Thangavelu Centre, Biotechnology and Bioinformatics Division, Jawaharlal Nehru Tropical Botanic Garden and Research Institute, Puthenthope, Thiruvananthapuram 695 586, IN
2 Department of Zoology, University College, Thiruvananthapuram 695 034, IN

Abstract

Venomous snakebite is a global serious health issue and in India high rate of mortality is caused by Naja naja (Indian cobra). To evaluate anti-cobra venom activity and identify lead molecules in Aegle marmelos, in vitro and in silico screening was carried out. Leaves, stem and ischolar_main bark of A. marmelos were extracted in ethanol, methanol and hexane and maximum yield was obtained in methanol. All extracts were used for testing in vitro anti-haemolytic, inhibition of anti-acetylcholinesterase and anti-proteolytic activities. The results revealed that ethanol extract of ischolar_main bark has high anti-haemolytic activity, methanol extracts of leaves have the highest inhibitory effect on venom induced anti-acetylcholinesterase activity and ethanol extracts of leaves have maximum anti-proteolytic activity. Docking between 81 phytochemicals from A. marmelos and each of the 14 cobra venom toxic proteins revealed that the plant contains potential molecules for detoxification of all the cobra venom proteins.

Keywords

Aegle marmelos, Cobra Venom, Docking, Phytochemicals, Snakebite.

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Bibin Varghese ¹, S. Sreelal ¹, S. Sreekumar ¹, P. Vinod ¹, M. N. Namboothiripad ¹, Joseph Lal ², K. Anand ²

Affiliations
1 Avionics Entity, and Vikram Sarabhai Space Centre, Indian Space Research Organisation, Thiruvananthapuram 695 022, IN
2 Advanced Space Transportation Systems, Vikram Sarabhai Space Centre, Indian Space Research Organisation, Thiruvananthapuram 695 022, IN

Abstract

This article describes the design details of a Wireless Instrumentation System that was experimented in ISRO’s recent Human in Space Project (HSP) Pad Abort Test (PAT) mission in piggy-back mode. The system consists of a few Wireless Sensor Nodes (WSNs) that acquire parameter data and a Wireless Base Station that collects these over an IEEE 802.15.4 compatible single-hop RF link and forward it to the telemetry subsystem. The circuit configuration, communication link and protocol as well as the measurement plan as adopted for HSP-PAT flight test are described to bring out the scalability of the architecture. The performance of the system in HSP-PAT mission is discussed in detail by way of PFA analysis results. All the parameters monitored through the system, including inertial ones such as acceleration and rotation were compared with reference data obtained from functional Telemetry Telecommand and Power and Navigation Guidance and Control chains and showed normal signatures. Maintaining an uninterrupted wireless communication channel in a hostile and crowded chamber like the Crew Module for all the nodes has called for a robust Medium Access Control (MAC) layer based on the industry-popular IEEE802.15.4 RF PHY. The requirement of such a robust MAC layer is established when the radio frequency links outage encountered in one of the WSN links during the interval of high vehicle dynamics is seen to be taken care of by the diverse link of the same node. A future roadmap towards self-powered wireless sensors is also outlined.

Keywords

Data Acquisition, Human In Space Project, Launch Vehicle Telemetry, Wireless Sensor Network.

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