Informatics Publishing Limited

S. N. Khan , B. M. Misra , R. K. Tiwari , H. S. Sehgal

Abstract

Five fungi namely, Coleosporium evodiae Diet., Phyllachora infectoria Cooke, Guignardia calami (H & P. Sydow) Von Arx and E Muller, Alternaria cassiae Jurair & Khan and Clados. porium uredinicola Speg have been described for the first time from India together with some new host records for India.

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Jyotsna Chauhan ¹, Rachna Tiwari ¹, R. K. Tiwari ²

Affiliations
1 Physics Department in Rajeev Gandhi Technical University Bhopal, IN
2 Physics Department in Jiwaji University Gwalior, IN

Abstract

The activity of fungicides is intimately related to its chemical structure. Knowledge about the chemical structure of a chemical is useful for the synthesis of new compounds with more specific actions and fewer adverse reactions, to increase/ decrease the duration of action of the original drug or to get a more potent compound, to restrict the action to a specific system of the body and to reduce the adverse reactions, toxicity and other disadvantages associated. We can understand the basic chemical groups responsible for drug action. Recently it has been observed that some of the fungicides are loosing their effects. So analogous compounds can be designed as substitute, if their structures are known. A rational approach to test these fungicides is to know the three dimensional structure of these compounds and macromolecular receptor sites as well as their molecular complex .The structures of these compounds can be obtained by X-ray diffraction method in crystalline form and they will invariably be similar to their structure in solutions.

Keywords

X-ray Crystallography, Systemic Fungicides, Triazole Structure.

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M. P. Singh ¹, S. P. S. Rawat ¹, R. K. Tiwari ¹, N. Q. Qazi ¹, S. P. Rai ¹, J. V. Tyagi ¹

Affiliations
1 Climate Change and Forest Influence Division Forest Research Institute, Dehradun, 248006, Uttarakhand, IN

Abstract

The purpose of this study was to establish rainfall-runoff relationship amongst the hydro-meteorological and vegetation characteristics and other site parameters at micro-watershed level. It brings out the assessment impact of forest on hydrological behavior. Efforts were made through present study, in which two micro-watersheds namely Arnigad (Dense Oak Forest) and Bansigad (Degraded Oak Forest) near Mussoorie, India were monitored continuously for the period of three years. The present study indicated that a dense forest cover regulates stream flow and controls the high peak flows, resulting in delayed discharge peaks which makes stream perennial and sustainable.

Keywords

Rainfall-runoff Relationship; Oak Forest; Key Words: Degraded Forest; Hydrological Processes; Micro-watershed

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P. N. Vijayaraghavan ¹, R. K. Tiwari ¹

Affiliations
1 Hindustan Copper Limited, Bandalamottu, Guntur District, Andhra Pradesh, IN

Abstract

Mineralisation is essentially confined to dolomitic host rock. The strict lithological control of mineralisation with its width extremes and layering defined by the bedding planes in the dolomite and the folding of mineralised zones conforming in style to that of the host rock are strong field evidences to suggest syngenetic origin of the deposit.

Due to structural complexity of the deposit, basic information from 100 m spaced drill intersections does not give correct picture regarding the disposition of ore bodies. No fixed norms for mining could, therefore, be established in advance and every mineralised section will have to be negotiated depending upon the structural domain and allied features governing the mineralisation in that particular section.

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S. Sri Lakshmi ¹, R. K. Tiwari ¹

Affiliations
1 Theoretical Modeling Group, National Geophysical Research Institute, Hyderabad - 500 007, IN

Abstract

The modern concept of fractal and chaos theory has invariably been applied to earthquake time series to understand the nature of earthquake dynamics and hence to characterize the model behaviour. However, prior to proposing an earthquake generating model and predictive behavior of earthquake data, it is essential to understand the possible influence of foreshocks and aftershocks on the earthquake dynamics.We study the impact of foreshocks and aftershocks on the nature of earthquake dynamics using the modern nonlinear forecasting approach. We used here monthly frequency earthquake data sets obtained from one of the most Seismo-Tectonically crucial regions of northeast India bounded by latitude 20-28°N and longitude 88-98°E, spanning over a time window of 1920-1988. For the present purpose, two sets of monthly earthquake time series are prepared: (i) original earthquake data and (ii) data after removing foreshocks and aftershocks, and then analyzed separately using the non-linear forecasting approaches. Comparative results indicate that earthquake data free from aftershocks and foreshocks show better predictive behaviour than the original data (i.e. combined with aftershocks and foreshocks), thus revealing a significant effect of foreshocks and aftershocks on the model characterization of earthquake dynamics.

Keywords

Fractals, High Dimensional Chaos, Foreshocks and Aftershocks, Nonlinear Forecasting Analyses, Northeast India Earthquakes.

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U. K. Singh ¹, R. K. Tiwari ², S. B. Singh ², S. Rajan ¹

Affiliations
1 National Centre for Antarctic & Ocean Research, Vasco Goa - 403 804, IN
2 National Geophysical Research Institute, Hyderabad 500 007, IN

Abstract

The artificial neural network (ANN) technique is at present most efficient and modern tool for parameter estimation and inversion of geophysical data. This paper deals with the application of ANN technique for the inversion of vertical electrical resistivity sounding(VES) data obtained from the NNW SSE part of Barmer district, Rajasthan. The efficiency of ANN technique is tested first on synthetic resistivity data generated from the numerical model and then trained on the actual VES field data. The analyses predict sediment thickness of the order of 172 m at Rawtra (S 15, and indicate that there is possibility of fresh aquifers at all sounding locations along the profile except at Sonadi (S 1). These results match with the depth-Resistivity structure obtained by the conventional method. However, the high accuracy and faster ANN imaging system seems to have highly correlated with that of conventional method for mapping the complex subsurface resistivity structures with less ambiguity. These finding also correlate remarkably well with known drilling results and geologic boundaries.

Keywords

Artificial Neural Network, Backpropagation Algorithm, VES Data, Resistivity Layer Parameters, Fresh Aquifer, Saline Aquifer, Barmer District, Rajasthan.

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R. K. Tiwari ¹, K. N. N. Rao ¹

Affiliations
1 Theoretical Geophysics Group, National Geophysical Research Institute, Hyderabad - 500 007, IN

Abstract

We examine here the latest available episodic and continuous records of long-term geo-hydro-bio-chemical processes using the non-parametric and modern spectral approaches. These analyses confirm the earlier findings of a 33 ± 3 million years (Myr) periodicity and reinforce that mega geo-bio-atmosphenc processes are cyclic in nature. Interestingly, six major extinction events coincide well with low phosphorous bunal rate (PBR) indicating that complex geochemical oscillations, probably caused by astronomically induced impact events, may have precipitated ocean productivity crisis leading to the biological upheaval in the earth's history. The present study combined with earlier evidence of a periodicity in the impact cratering record may provide a significant constraint on any theoretical framework attempting to unify terrestrial observations in widely different fields.

Keywords

Mega Geocycles, Phosphorus Burial Rate, Galactic Cycles, Spectral Analyses, Cychcity in Earth-Processes.

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R. K. Tiwari ¹, K. N. N. Rao ¹

Affiliations
1 Theoretical Geophysics Group, National Geophysical Research Institute, Uppal Road, Hyderabad - 500 007, IN

Abstract

The Northeast Indian region (NEI) is characterised by frequent earthquakes associated with swarms and quiescence activities. To gain physical insight about its origin, inter-event time series of earthquakes M≥3 and 5 has been analysed using rank-order statistics and non-linear perspective. The rank-order statistics of inter-event time series intlicates "mixed response" with distinct breaks in slope suggesting unstable, quasi-deterministic and random recurrence time that is sensitive to earthquake dynamics. The break in "slope" possibly suggests that the long term (of recurrence time > 400 days) earthquake dynamics in this region is unstable. The middle segment representing the time range of approximately 30-400 days can be described by Power Law function indicating the possible element of determinism on this time scale. Lastly, the existence of "roll off" towards higher rank-order, however, seerns to indicate the transition in the nature of structure. In order to constrain these results, we further compute the second order Kolmogorov-Sinai entropy (K₂), which reveals a coherent time structure with predictive time limit of about 12 to 16 months, indicating a quasi-deterministic dynamics that apparently is also evident (Power Law) in rank-order statistics. This predictive time limit seems to be too short to be associated with major global tectonics. We therefore, propose an alternative possible physical mechanism, which may coexist with regional tectonics. In the light of present results, we suggest that surface/subsurface water infiltration into the main fractures and faults during a favourable season could increase the pore pressure thereby triggering frequent earthquakes, particularly in critically unstable tectonic regions.

Keywords

Earthquakes, Power Law, Random, Deterministic, Rank-Order, Entropy, Northeast India.

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R. K. Tiwari ¹, R. P. Gupta ¹, M. K. Arora ²

Affiliations
1 Department of Earth Sciences, Indian Institute of Technology-Roorkee, Roorkee 247 667, IN
2 Department of Civil Engineering, Indian Institute of Technology-Roorkee, Roorkee 247 667, IN

Abstract

This article presents results on surface ice velocity of the Chhota-Shigri glacier, Himachal Himalaya, deduced by applying sub-pixel image correlation technique (COSI-Corr software) on the ASTER time series data (2003-2009). The remote sensing-derived measurements are found to match quite well with the field measurements. In general, the surface ice velocity varies from ∼20 m/yr to ∼40 m/yr. Velocity variations occur in different parts of the glacier and also from year to year. In all the years considered for this glacier, the mid-ablation zone and the accumulation zone exhibit higher velocities and zones near the snout and equilibrium line altitude have relatively lower velocities. Further, the velocities are found to be relatively higher in the years 2005-2006 and 2007-2008 and lower in the years 2006-2007 and 2008-2009. These spatial and temporal variations in velocity, which could be related to the glacier morphology and hydro-metrological factors, need to be further studied.

Keywords

Glaciers, Optical Image Correlation, Remote Sensing, Sub-Pixel Images, Surface Ice Velocity.

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R. P. Gupta ¹, N. Srivastava ², R. K. Tiwari ¹

Affiliations
1 Department of Earth Sciences, Indian Institute of Technology-Roorkee, Roorkee 247 667, IN
2 Planetary Sciences and Exploration Programme, Physical Research Laboratory, Ahmedabad 380 009, IN

Abstract

It is generally believed that the Moon became inter-nally dead ∼1 b.y. from the present, and only old ( 1 b.y.) volcanic flows forming largely the mare basins are known to occur. The old volcanic land-forms stand largely obliterated and flows studded with impact craters. However, recent findings have indicated global presence of young thrust faults on the Moon, escape of gases from the interior and also pre-dicted the presence of partially molten lower lunar mantle and core. Here, we have used high-resolution datasets from NASA's LRO, Kaguya of JAXA and ISRO's Chandrayan-1 missions to examine the char-acteristics and origin of multiple relatively fresh, coaxial, superposed viscous flows spotted inside the Lowell crater on the far side of the Moon. Various considerations apparently rule out the possibility of these melts being derived from nearby areas. An asso-ciated likely source crater and tectonic structures (a fault and a fracture) of two different ages but emanat-ing from the same crater and affecting different flows have also been located - exhibiting tectono-volcanic relationship. These features provide evidences of like-ly volcanic activity in the region not too far in the past, are consistent with recent results that the Moon may not be internally dead, and thus have implica-tions to the thermal history and present-day geologic nature of the Moon.

Keywords

Craters, Moon, Tectonic Features, Volcanic Flows.

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Bharti Mishra ¹, R. K. Tiwari ²

Affiliations
1 S.O.S. Physics, Jiwaji University, Gwalior, Madhya Pradesh, IN
2 Jiwaji University, Gwalior, Madhya Pradesh, IN

Abstract

Structural analysis of medicinal compound is important for understanding of the compound and its interaction as a medicine. In the present paper, the chemical studies on Suphamethoxazole (C₁₀H₁₁N₃O₃S) carried out by Gaussian 09 software to determine total energy, molecular energies and atomic mass distributions and also calculate the bond lengths bond angles and torsional angles. And its structural analysis using X-ray technique has been done after growing it with slow evaporation using methanol as a solvent.

Keywords

Sulphamethoxazole, Single Crystal, Medicinal Compound, Slow Evaporation, Crystal Arrangement.

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