Biochemical study of the gonads of Mystus vittatus exposed to the fertilizer NPK during the spawning season. Part 1: Carbohydrates     

A. S. Narain  R. K. Pande 《洁净——土壤、空气、水》1988,16(6):643-647

The gonads of spawning Mystus vittatus exposed for 96 h to the LC₅₀-96 h dose (i.e. 550 ppm) of NPK, the agricultural fertilizer, were biochemically analysed for their carbohydrate content. The glucose and glycogen contents of the spawning fish were found to be lowered significantly, and the total carbohydrate and lactic acid contents altered insignificantly, under the pollutional stress. The stressed fish also exhibited the presence of some additional free sugars within their gonads.  相似文献   

Studies on the Lipid Contents in the Gonads during the Annual Reproductive Cycle of Mystus vittatus under the Stress of Agro-Chemical NPK-Fertilizer     

R. K. Pande  A. S. Narain  S. K. Pande 《洁净——土壤、空气、水》1989,17(3):345-348

Specimens of either sex of the freshwater catfish Mystus vittatus were exposed to an acute toxic dose of an agro-chemical NPK, i.e. 550 ppm during the spawning phase of their annual reproductive cycle. The effects on total lipid and its various fractions, viz. phospholipids and cholesterol, were studied in the testes and ovary. The total lipid content of the gonads of unstressed fish showed lowest values during the spawning phase when compared to other phases, the content remained higher in the ovary than in the testes. In fish subjected to NPK-stress during the spawning period, the fall in total lipid content of the gonads was found to be much greater than that in the controls. The phospholipids content of the gonads of unstressed fish showed highest values during the spawning phase when compared to other phases; the content remained higher in the ovary than in the testes. In fish subjected to NPK-stress during the spawning phase the rise in the gonads was found to be higher than that in the control. The cholesterol content of the gonads of unstressed fish showed highest values during the spawning phase when compared to other phases; the content remained higher in the ovary than in the testes. In fish subjected to NPK-stress during the spawning period the rise in the cholesterol content of the gonads was not found to be as high as that in the controls. Agro-chemical NPK seemed to effect the total lipid and cholesterol content adversely during the spawning phase, affecting the vitellogenic process without affecting the biosynthesis of phospholipids as such, which on the contrary increases. The decrease of lipid and cholesterol mobilization from liver to gonads seemed to be restricted as a result of NPK action.  相似文献   

Biochemical Study of the Gonads of Mystus vittatus (Bl.) Exposed to the Acute Toxic Dose of NPK During the Spawning Season: Protein and Amino Acids     

R. K. Pande  A. S. Narain 《洁净——土壤、空气、水》1989,17(5):597-601

The freshwater catfish, Mystus vittatus, were exposed to the LC₅₀, 96 h dose (i.e. 550 ppm.) of the agro-fertilizer NPK for 96 h, during the spawning period (March–June). Their gonads were biochemically analysed for the total protein content and the free amino acids. The protein content of the gonads of the stressed fish was found lowered. The fish also showed disappearence of certain amino acids from their gonads.  相似文献   

Crustal structure of the Indian subcontinent     

Hari Narain 《Tectonophysics》1973,20(1-4):249-260

Studies carried out by various investigators up to 1971 to delineate the Indian crustal structure using body wave travel times, surface wave dispersion and gravity methods are summarised and reviewed. The average crustal thickness is found to be 35–40 km in the Indian peninsular shield, 30–35 km in the Indo Gangetic plains and 60–80 km in the Himalayas and the Tibetan plateau region. The limitations of the various methods used and the errors in the estimation of crustal thickness by them are discussed. As no deep refraction work for crustal studies has been carried out so far in India, this topic is not covered in this study.  相似文献   

On dielectronic recombination coefficients of the H,He and Ne sequences     

N. K. Jain  Udit Narain 《Solar physics》1976,50(2):361-363

A modified expression for dielectronic recombination coefficients for the recombining ions pertaining to the H, He and Ne sequences is presented. The results are in nice agreement with the extensive computations of Ansari et al. (1970) for the cases considered.  相似文献   

Overview of some recent geophysical investigations in Himalaya     

Hari Narain 《Tectonophysics》1980,62(1-2)

Recent work on long-period surface wave dispersion investigations and other geophysical work have shown that in the Himalayan and Tibet Plateau region the crust is extremely thick and the velocities are low: However, the upper mantle below Tibet appears to have normal velocities. Seismic Research Observatories, being established in the vicinity of Himalaya, will be extremely useful for near-source investigations due to their digital data acquisition capabilities and much larger dynamic range. Quantitative seismicity maps prepared for the Himalayan region are useful in comprehending regional tectonics. With international collaboration, Deep Seismic Sounding surveys have been successfully carried out in western Himalaya. It is inferred that the northern boundary of the Indian Plate does not lie along the Main Central Himalayan Thrust or the Indus Suture line, but falls very much north of the combined Indo-Tibetan block. Focal mechanism studies are, by and large, consistent with the northward thrusting of the Indian Plate. Conflicting results regarding the prevalence of isostasy in the Himalayan region have been obtained from gravity surveys. Geophysical investigations and observational facilities need to be intensified for a better understanding of the tectonics.  相似文献   

The protocontinental growth of the Indian Shield and the antiquity of its rift valleys   总被引：1，自引：0，他引：1  

S.M. Naqvi  V. Divakara Rao  Hari Narain 《Precambrian Research》1974,1(4):345-398

The evolution of the Indian Shield has been envisaged from the analysis of available tectono-lithostratigraphic, geochronological, geochemical and geophysical data. It appears that the Dharwar schist belts and their equivalents, except the Kolar schist belt, are not typical greenstone belts, but are representative of a transitional era of rapid transformation from simatic to sialic crust. In the Archaean—Proterozoic tract of India, relics of rocks older than 3.0 b.y. are identified in five widely separated regions of distinct tectono-litho-stratigraphic assemblages which probably represent the primordial continental nucleii. It is suggested that the growth of the Indian Shield has taken place through nucleation, accretion and merger into three protocontinents named Dharwar, Aravalli and Singhbhum. The cratonisation of the Indian unit seems to have been rapid and almost completed by the middle Proterozoic, as there is no significant variation in the composition of the clastic sediments and basalts from middle Proterozoic onwards. The continental nucleii appear to merge along the deep-seated lineaments, which are reflected on the tectonic map of India. Further, the Dharwar, Aravalli and Singhbhum protocontinents also seem to merge along a Y=shaped Narmada—Son—Godavari lineament which along with the Mahanadi lineament, between the two continental nucleii of the Singhbhum protocontinent have later developed into rift valleys.  相似文献   

A Similarity Solution of Hide's Magnetic Wave Equation     

Janardan G. Negi  Rishi Narain Singh 《Geophysical Journal International》1974,39(2):407-409

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Radiative recombination in some ions of astrophysical interest     

Udit Narain  H. P. Mital  Suresh Chandra 《Solar physics》1977,52(2):417-422

Radiative recombination coefficients for some quadruply and quintuply ionized atoms, present in the Sun and its atmosphere, are investigated in the temperature range 10–10⁴ K by using the method of detailed balance. Simple expressions are given for a quick estimation.  相似文献   

On the estimation of the vertical distribution of radiogenic heat production in the crust     

Rishi Narain Singh  Janardan G. Negi 《Geophysical Journal International》1980,62(1):221-224

Summary. A differential-difference equation governing the distribution of radiogenic heat in the crust has been obtained. The solution of this equation gives the exponential model of the heat production distribution with the logarithmic decrement as determined in Singh & Negi.  相似文献