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V. K. Gahalaut ¹, R. Chander ¹

Affiliations
1 Department of Earth Sciences, University of Roorkee, Roorkee 247667, IN

Abstract

The data presented suggest that uplift of the outer Himllaya in this region is continuing even today through sudden co-seismic elevation changes during large thrust earthquakes and secular aseismic uplift during intervals between such earthquakes. The observed co-seismic ground elevation changes during the Kangra earthquake are interpreted so as to simulate the cross-sectional shape of the buried active thrust fault responsible for this continuing episodie as well as secular uplift of the Outer Himalaya. This fault is assumed to be the surface of detachment between the Himalayan rocks above and the Indian shield rocks below. It is concluded that over most of its extent in Dehra Dun region, the detachment surface has gentle dip to the northeast but a few interspersed, northeast dipping steeper ramps are not ruled out. The depth of the detachment is estimated to be between 0 and 3 km beneath the SW limit and about 10 km beneath the NE limit of the Outer Himalaya in the Dehra Dun region. The two main levelling observations regarding the current inactive status of the Main Boundary Thrust (MBT) are, (1) the involvement of this thrust in the occurrence of the Kangra earthquake is definitely ruled out from the levelling data, and (2) the measured rate of secular uplift of the ground increases from NE to SW across the surface trace of the thrust suggesting that the Outer Himalaya is rising faster than the Lesser Himalaya to the NE across the MBT.

Keywords

Ground Elevation, Earthquake, Tectonism, Dehra Dun.

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R. P. Gupta ¹, R. Chander ¹, A. K. Tewari ², A. K. Saraf ²

Affiliations
1 Department of Earth Sciences. University of Roorkee, Roorkee-247667, IN
2 Department of Earth Sciences, University of Roorkee, Roorkee-247667, IN

Abstract

Liquefaction in saturated sandy soils as a result of earthquake-induced shaking, poses a major threat to men and materials. Many parts of the Indo-Gangetic plains have experienced such catastrophes repeatedly. The border region of southern Nepal-northern Bihar (India) is a typical existing setting prone to soil liquefaction in the Indo-Gangetic Plains. The Bihar-Nepal earthquake of 1934 (M_s>8) and the earthquake of 1988 (M_b = 6.7) induced extensive liquefaction in the terrain in living memory. Characteristics of soil in this area of nothern Bihar have been determined from field samples. Various parameters (e.g. clay content, D₅₀ - and C-values) indicate high susceptibility to liquefaction among soils in the area.

A close study of remote sensing data (Landsat TM and MSS) products reveals that the boundaries of liquefaction zone in the Bihar-Nepal region during the 1934 earthquake are identifiable on the remote sensing images. This is due to a combination of several inter-related factors, such as landform, soil type, soil moisture and vegetation. These clues have been applied as guides on the adjoining remote sensing images for delineating areas on a regional scale, where liquefaction might possibly occur in the Ganga plains, in the event of future Himalayan earthquakes.

Keywords

Earthquakes, Ganga Plains, Remote Sensing, Seismology.

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R. Chander ¹, Kalpna ¹

Affiliations
1 Department of Earth sciences, University of Roorkee, Roorkee-247 667, IN

Abstract

The individual thrust-fault type fault plane solution of the 1991 Uttarkashi earthquake is considered along with a reverse fault type and a strike-slip type composite fault plane solutions for the Garhwal Himalaya. The two latter solutions are based on data from 49 small and micro-earthquakes. All 50 earthquakes occured in the vicinityof Main Central Thrust over a distance of about 150km from Yamuna to Alaknanda valleys. The data are consistent with the view that a thrust-fault type stress environment prevails throughout the uppercrust in the region. The maximum effective principal stress (σ1) is horizontal to sub-horizontal with azimuth along N42° everywhere in the upper crust except in the hypocental region of the Utrarkashi earthquake, where it is N26°. lntermediate effective principal stress (σ2)is horizontal in the NW quadrant and the minimum effective principal stress (σ3) is vertical to sub-vertical correspondingly. Reactivation of the strike-slip faults occurs under the influence of σ1 and σ2. This is within the theory of fault reactivation under general three dimensional stresses. Pore pressures could be relatively high and may approach lithostatic levels over most parts of upper crust in the region.

Keywords

Seismology, Garhwal Himalaya.

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V. K. Gahalaut ¹, R. Chander ¹

Affiliations
1 Department of Earth Sciences, University of Roorkee, Roorkee - 247 667, IN

Abstract

We interpret here the ground elevation changes along the Saharanpur - Dehradun - Mussoorie line as brought out through the levelling surveys of 1905-07 and 1926-28. These data can be simulated with a model of slips, varying in amount between 3 ± 3 and 16 ± 8 cm, on the same subsurface detachment on which the great Kangra earthquake of 1905 may have occurred as argued elsewhere in the literature. Since ground elevation changes occurred in the Dehradun region during the Kangra earthquake also, we suggest that slips related to plate tectonics on the detachment lead to ground elevation changes partly aseismically during periods between great earthquakes and partly coseismically at the times of such earthquakes. The annual rates of slips obtainable from the above numerical results being much less than the estimated rate of 18 ± 7 mm/year for plate convergence accommodated at the Himalaya, we conclude that earthquake generating strains accumulated in the Dehradun region during the 21 years between the two levelling surveys.

Keywords

Geodetic Levelling, Dehradun Region, Outer Himalaya, Plate Tectonics

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A. Chandra ¹, R. Sabharwal ², R. Chander ¹, F. Mahdi ¹, A. A. Mahdi ³

Affiliations
1 Era’s Lucknow Medical College, Lucknow, U.P, IN
2 Punjab Institute of medical Sciences Jalandhar, Punjab, IN
3 C.S.M. Medical University, Lucknow, U.P, IN

Abstract

Background: Diabetes is one of the commonest and serious metabolic disorders. Much of the morbidity and mortality associated with diabetes is primarily attributed to sequelae requelac of microvascular and macrovascular changes, in which diabetic dyslipidemia is one of the many modifiable risk factors for coronary artery disease, stroke and peripheral vascular disease.

Objectives: The main aim of this study was to evaluate the hypoglycemic and antidyslipidemic effect of selected Indian plants in streptozotocin induced diabetic rats.

Material and Methods: Azadirachta indica and Ocimm sanctum leaves, Allium sativum bulbs and Momordica charantia fruits were collected, identified taxonomically and extract was obtained. Male Albino rats was used and divided into 8 groups, each consisting of 6 animals, one group act as a control. Diabetes in rats was induced with streptozotocin. Blood samples were collected and biochemical analysis was done for blood sugar, lipid peroxide and lipid profile. The diabetic group without drug treatment was compared with the control, and diabetic plus drug-treated groups were compared with the diabetic group without drug treatment. Data were analyzed using Student 't' test.

Results: Our results revealed that administration of streptozotocin in rats caused increase in the levels of glucose, lipid peroxides, cholesterol and triglycerides with lessening of the HDL-cholesterol. Treatment with aqueous extracts of Momordica charantia, Allium sativum, Azadirachta indica and Ocimum sanctum not only reduced the level of blood glucose but also caused lowering of total cholesterol and triglycerides following an increase in the level of HDL-cholesterol.

Conclusion: We concluded that the herbal plants tested possess both hypoglycemic and antidyslipidemic activities and their use as a therapeutic tool in diabetes related complications encourage further investigation in this field.

Keywords

Diabetes, Dyslipidemia, Indian Herbs, Lipid Peroxidation.

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R. Pratap ¹, R. C. Gupta ¹, R. Chander ¹, A. K. Khanna ¹, Vinita Singh ¹, N. K. Kapoor ¹, A. K. Srivastava ¹, D. Raina ¹, S. Singh ¹, A. Ghatak ¹, O. P. Asthana ¹, S. Nityanand ¹, Sukh Dev ², Nitya Anand ¹

Affiliations
1 Central Drug Research Institute, Lucknow 226 001, IN
2 Ambedkar Research Centre, Delhi University South Campus, New Delhi 110 021, IN

Abstract

The increasing incidence of disorders due to metabolic syndrome, which include hyperlipidemias, diabetes and hypertension, has taken serious dimension world over, including in India, and has become a matter of deep concern. Drugs which can inhibit more than one disorder of this syndrome would add much therapeutic value to its management. 3β -Hydroxy-5,16- pregnadien-20-one (80-574, 2), selected based on the structural lead of the presence of a β -enone pharmacophore in/around ring D of Guggulsterone (1), the main active constituent of the phytopharmaceutical Gugulip developed at CDRI, Lucknow from the Ayurvedic herbal drug Gum Guggul, has been found to exhibit both hypolipidemic and hypoglycemic activities in the conventional experimental animal models used for studying these activities. In mode of hypolipidemic action studies in high fat diet-fed rats, compound 80-574 was found to enhance lipolysis of serum lipoproteins, enhance the uptake of LDL by hepatocyte membranes, indicating increased catabolism of LDL, and caused increased faecal excretion of bile acids indicating enhanced mobilization of cholesterol from fatty deposits. Compound 80-574 also exhibited antioxidant activity in in vitro and in vivo experimental models, and protected LDL against oxidation, indicating protection against atherogenesis. Compound 80-574 also exhibited moderate inhibition of cholesterol biosynthesis in liver slices. Treatment with 80-574 also improves glucose tolerance in diabetic rats. With these multiple sites of hypolipidemic action accompanied with its hypoglycemic activity, compound 80-574 appears a promising candidate for the treatment of dyslipidemias and diabetes and thus for management of metabolic syndrome. A synoptic view of the various functional activities exhibited by compound 80-574 is presented in this article.

Keywords

Diabetes, Lipoproteins, Lipid Peroxides, Triglycerides.

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