Showing papers by "Jawaharlal Nehru University published in 1977"
TL;DR: The results suggest that the rate of RNA synthesis depends on the overall rate of protein synthesis, and that cAMP inhibited the overall synthesis of protein.
27 citations
TL;DR: Urban malaria, and one might say Anopheles stephensi malaria, is probably more widespread and more significant as an important public health problem than in former times, and once the campaign faltered malaria seems to have diffused from the four foci suggested.
Abstract: The eradication campaign faltered, for historical reasons some of which are tentatively suggested above and which would be worthy of fuller study as an important part of recent medical history; it is one of those historical topics so intertwined with political and social history that an interdisciplinary approach would be fruitful — if the necessary documents could be made accessible, in India and perhaps in international organisations and subscribing government archives too.
23 citations
TL;DR: The oxygen-dependent damage which develops in barley seeds with approximately 7-8 per cent moisture content disappears after post-irradiation storage in vacuo and the oxygen-independent damage which increases with storage at high temperature is further potentiated by caffeine.
Abstract: The oxygen-dependent damage which develops in barley seeds with approximately 7-8 per cent moisture content disappears after post-irradiation storage in vacuo for 48 hours at 40 degrees C and for 24 hours at 50 degrees C. When the diration of storage at 40 degrees C is extended to 384 hours, oxygen-independent damage becomes potentiated. There is oxygen-dependent damage in seeds of approximately 13.3 per cent moisture content and after the seeds have been stored in vacuo at 50 degrees C, the oxygen-dependent damage begins to increase by 168 hours, and it is very significantly potentiated by 192 hours. Under these circumstances, caffeine acts as a radioprotector only as long as the precursors of oxic damage are present in the seeds. Once these sites are lost, caffeine acts only as a radiosensitizer. The oxygen-independent damage which increases with storage at high temperature is further potentiated by caffeine.
9 citations
TL;DR: In this article, the authors make an attempt to explore the factors that contribute to differential levels of entrepreneurial performance by studying the specific activities of the entrepreneurs and relate them to their environment and their social background in a comparative frame.
Abstract: neurs are adaptive, however, their specific modes of adaptation may differ. Some modes may ensure a higher level of entrepreneurial performance than others. Further, the modes of adaptation in turn are dependent on the environmental pressures operating on the entrepreneurs and their specific social background. Hence in order to explore the factors that contribute to differential levels of entrepreneurial performance it is necessary to study the specific activities of the entrepreneurs and relate them to their environment and their social background in a comparative frame. This paper makes such an attempt. The general orientation to the study of entrepreneurs in this paper would closely follow Kilby’s approach which steers clear of a priori discussions of what constitutes entrepreneurship and concentrates on ’the specific kinds of activities that the entrepreneur himself may have to perform for the successful operation of his enterprise....’ (1971: 27). Such an approach would lead us to study both the work world and the non-work world of the entrepreneurs and would enable us to examine the extent of overlap and the interconnections between -them. It would also lead us to examine
8 citations
TL;DR: The roots of urbanism go deep into Indian history, and any attempt to see the various forces in clear array must place them in the perspective of time: more so since the social process in India over the past century or as mentioned in this paper.
Abstract: Over sixty years ago Petrick Geddes wrote his Report on re-planning of six towns in Bombay Presidency (1915), prior to his appointment as the first Professor of Sociology in the University of Bombay. Geddes occupied the Chair only briefly; and G. S. Ghurye, his successor, wrote on the ’Cities of India’ in the March 1953 issue of Sociological bulletin. During the years in between and since, sociologists and others have off and on referred to urban phenomena in India; but this terrain has until recently remained singularly devoid of decisive intellectual landmarks: the key ideas which, cutting through thickets of data, clearly show the road ahead. The problem has its difficulties; but the time has come to confront them, howsoever tentatively.’ The roots of urbanism go deep into Indian history, and any attempt to see the various forces in clear array must place them in the perspective of time: more so since the social process in India over the past century or
8 citations
28 Sep 1977
TL;DR: The changes in the fluorescence of ANS bound to heat-treated chloroplasts plausibly reflect the nature of the structural changes in chloroplastics during the heating upto 55‡ C and indicates that heat-treatment caused some alteration of the microstructure of thylakoid membranes of chloroplast besides the usual loss in the O2 evolving capacity.
Abstract: Structural changes in the chloroplast membranes caused by acidification and heat-treatment are studied by observing the changes in the fluorescence of ANS bound to thylakoid membranes. On addition of acids to buffered suspension of isolated pea chloroplasts, the fluorescence intensity of bound ANS shows a sigmoidal rise on reaching a pH value of about 4.5. A part of the fluorescence enhancement of bound ANS brought about by protons is not reversible on back titration with alkali. The reversible part of acid induced rise in ANS fluorescence possibly reflects structural changes expected to be associated with photophosphorylation. Divalent cations enhance the fluorescence of ANS bound to chloroplasts between a pH range 4.5–7.0 but diminish it if the pH is below 4.5. Addition of acid to heat-treated chloroplasts shows similar sigmoidal rise in ANS fluorescence intensity on lowering the pH to about 4.5. On addition of acid upto a pH of 3.1, the ANS fluorescence is greater than that of untreated chloroplasts, however, at pH below 3.1, the fluorescence of bound ANS is lower than the control chloroplasts. This observation indicates that heat-treatment caused some alteration of the microstructure of thylakoid membranes of chloroplasts besides the usual loss in the O2 evolving capacity. This is further confirmed from the studies of Hill-activity and ANS binding to chloroplasts incubated at various temperatures in the absence and presence of aliphatic alcohol. Hill-activity (DCPIP reduction) of chloroplasts incubated at temperatures between 25‡ C and 55‡ C first increases reaching a maximum at 45‡ C and then declines rather sharply, when the chloroplasts are heated beyond 45‡ C (Tmax). The presence of 200 mM n-butyl alcohol or 40 mM n-amyl alcohol during the warming treatment lowers the temperature by 8‡ C at which the decline in the Hill-activity is observed. An enhancement in the fluorescence intensity and a blue shift of the emission spectrum of bound ANS are noted if the chloroplasts are heated beyond the Tmax either in absence or presence of alcohol. The changes in the fluorescence of ANS bound to heat-treated chloroplasts plausibly reflect the nature of the structural changes in chloroplasts during the heating upto 55‡ C.
7 citations
6 citations
01 Dec 1977
TL;DR: In this article, pole-placement technique, Lyapunov's direct method and optimal linear state-regulator formulation are employed to design stable and optimal controllers for a 2-shaft gas turbine using the model proposed by Mueller.
Abstract: In this paper, pole-placement technique, Lyapunov's direct method and optimal linear state-regulator formulation are employed to design stable and optimal controllers for a 2-shaft gas turbine using the model proposed by Mueller. Analysis and comparison of small-signal transient behaviour of the original system and system with controller are also given.
6 citations
TL;DR: Adding of L-threonine in the diet, not only could cure the signs developed due to excess tyrosine, but also could affect the levels of enzymes studied.
Abstract: The objective of this study was to determine the effect of threonine supplementation on tyrosine metabolism in rats fed a low protein diet with excess tyrosine. The growth retardation and the development of eye and paw lesions that occur in rats ingesting a basal plus 3% or 5% L-tyrosine diet could be alleviated partially by the addition of 0.5% or 1.0% L-threonine to the diet. An increased blood tyrosine level in rats fed excess tyrosine was also lowered by threonine supplementation. In tyrotoxic conditions, the activities of liver tyrosine transaminase (EC 2.6.1.5) and threonine dehydratase (EC 4.2.9.16) were elevated, but p-hydroxyphenyl pyruvic acid oxidase (EC 1.13.11.27) which is also intimately associated with tyrosine toxicity was found to be inactivated. Furthermore, biosyn thesis of ascorbic acid in liver was significantly lowered in this condition. However, addition of L-threonine in the diet, not only could cure the signs developed due to excess tyrosine, but also could affect the levels of enzymes studied. J. Nutr. 107: 1575-1582, 1977.
6 citations
TL;DR: The results suggest that phytochrome regulation of peroxidase activity in maize is not regulated via hormones, acetylcholine or cAMP.
4 citations
TL;DR: In this article, the modification of radiosensitivity of barley seed with 1.75 × 10−3 M and 3.8 × 10 −3 M concentrations of caffeine and ascorbic acid during irradiation in oxygenated and oxygen-free hydration medium was studied at 25 and 37°C, respectively.
TL;DR: Two types of interspecific amoeba hybrids, viz.
TL;DR: In this article, the authors estimate the amplitude using dispersion relation and show that the absorptive part contributes less than 100 keV to the partial width of the Okubo-Zweig-Iizuka rule.
Abstract: The Okubo-Zweig-Iizuka rule forbids the transitionB(1235)→φπ. Unitarity, however, induces a non-vanishing amplitude forB→φπ. We estimate the amplitude using dispersion relation. The absorptive part is shown to be small contributing less than 100 keV to the partial width Γ (B→φπ). For the dispersive part we evaluate the contributions of the\(K*\bar K\) and\(K**\bar K\) intermediate states and point out that the\(K*\bar K*\) state does not contribute significantly. The dispersive part contributes about 300 keV to the partial width. Thus unitarity correction to the Okubo-Zweig-Iizuka rule gives the partial width Γ(B→φπ) to be around 300–400 keV compared with the present experimental upper limit of 1·9 MeV.
TL;DR: The non-linear differential equations describing the Volterra-Gause-Witt system have been solved in the framework of the Brillouin-Wigner perturbation method and expressions for the population densities of the species and the frequencies of oscillations have been obtained.
TL;DR: Experiments with RNA and protein synthesis inhibitors indicate that the appearance of these new enzyme activities are dependet on concomitant new protein synthesis and the inducer operates at a transcriptional level.
Abstract: The levels of hepatic threonine dehydratase and tryptophan pyrrolase are elevated in 5% tyrosine-fed rats, and these increases are dependent on the dietary tyrosine level. Experiments with RNA and protein synthesis inhibitors indicate that the appearance of these new enzyme activities are dependet on concomitant new protein synthesis and the inducer operates at a transcriptional level.