Browsing by Author "S.N. Singh"

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A Chance Mechanism of the Variation in the Number of Births Per Couple
(1968) S.N. Singh
Under certain assumptions a probability distribution for the variation in the number of births per couple has been derived. The distribution involves several parameters. A procedure to find the B.A.N. [best asymptotically normal] estimates of the parameters is outlined. One example of the application of the distribution is discussed in some detail. Copyright Taylor & Francis.
A class of exact solution of magnetohydrostatics
(1989) S.N. Singh; C. Thakur
A simple reduction of magnetohydrostatics to a partial differential equation involving two functions has been achieved. Appropriate specialization of the latter is shown to lead to new solutions to the original equation.
A class of exact solutions and physical behaviour of magnetic field lines in plasma column
(Springer India, 1988) S.N. Singh; D.D. Tripathi
Using hodograph and Legendre transformation functions the basic equations are recast in terms of this function, and the conditions which this function should satisfy are stated. Several applications of this method are considered, and the geometry of magnetic field lines is discussed. © 1988 Indian Academy of Sciences.
A generalized parity dependent model for couple fertility
(1978) S.N. Singh; I.J. Singh
A probability distribution for the number of conceptions to a female during a given time interval since marriage has been derived assuming fecundability to be parity dependent. The distribution involves several parameters. A procedure for finding the estimate of some of the parameters has been outlined. The model has been applied to some observed distributions. The use of the model in the evaluation of family planning programme is also illustrated.
A modification of a continuous time model for first conception
(1976) S.N. Singh; K.C. Chakrabarty; V.K. Singh
The interval between marriage and the first conception leading to a live birth plays an important role in the determination of fertility components. Several probability models (Potter and Parker, 1964; Singh, 1961, 1964, 1967) based on varying sets of assumptions relating to this interval have been propounded in the recent past. All of them are based on the assumption that the females under study are susceptible to conception at the time of marriage. However, in certain situations, where some of the females already pregnant at the time of marriage report to have conceived within a short interval following marriage, this condition is not satisfied and these models become unsuitable. A probability distribution which is an inflated form of the continuous model proposed by Singh, for the time of the first conception leading to a live birth, is presented in this paper. It describes reasonably well the data on first conception times in the context of premarital conceptions. Simple expressions for the maximum likelihood estimators of the parameters involved in the model are obtained and a method for finding the asymptotic covariance matrix of the estimators is outlined. The model is applied to four sets of data. © 1976 Population Association of America.
A probability model for forward birth interval
(1979) S.N. Singh; R.C. Yadav; A. Pandey
[No abstract available]
A probability model for the number of births in an equilibrium birth process
(Springer India, 1981) S.N. Singh; V.K. Singh
A probability model for the number of complete conceptions (that is, live births) taking into account foetal wastages, occurring in a couple during a specified period of time (T0, T0+T) is developed assuming that the data was collected starting a long time after marriage. A method of estimating some of the underlying parameters is given. The model is applied to data obtained in a Varanasi Survey in 1969-70. © 1981 Indian Academy of Sciences.
A study of pattern of out- migration: a regression analysis ( India).
(1984) S.N. Singh; H.I. Sharma
Regression analysis is used to measure the significance of the following three factors in determining the amount of rural-urban migration from villages in the Varanasi area in India: average farm size; proportion of households belonging to upper castes; and distance from Varanasi city. -D.Conyers (CDS)
A study on the fertility of migrants
(1981) S.N. Singh; R.C. Yadava; K.N.S. Yadava
This study explores the impact of temporary separation due to the migration of males leaving their wives at home, on fertility through a theoretical model proposed under reasonable assumptions. The application of this model to an observed set of data relating to migrants from a rural area indicates that although the fertility of such separated couples is slightly lower than the couples living together, their fecundability is quite high (0.18) in comparison to the fecundability (0.05) of the couples living together.
Activity and expression of aspartate aminotransferase during the reproductive cycle of a fresh water fish, Clarias batrachus
(Springer Netherlands, 1999) A.S. Srivastava; I. Oohara; T. Suzuki; S.N. Singh
Aspartate amino transferase (AspT; EC: 2.6.1.1) is one of the key enzyme of aspartate malate shuttle and non-essential amino acid metabolism. In order to clarify the change of the activities of both cytosolic (c-) and mitochondrial (m-) AspT isoenzymes during the different reproductive stages of Clarias batrachus, an air-breathing carnivorous freshwater fish, the c- and m- AspT activities were measured spectrophotometrically in liver, heart, kidney, brain and ovary during the pre-spawning, spawning and post-spawning phases of the annual reproductive cycle of this fish. Maximum activities were observed during the spawning phase, followed by pre- and post-spawning phases. The native agarose gel electrophoretic pattern revealed two AspT forms, c-AspT and m-AspT, throughout the pre- to post-spawning phases. However, the spawning phase was marked by the expression of an additional anionic form of c-AspT in all tissues studied. These results indicate a distinct utilization of aspartate particularly in the spawning phase in fish in the central metabolic path via transamination reactions, and suggest a control of the enzyme activity by the expression of the additional c-AspT gene, especially at the spawning phase.
Age-dependent response of lactate dehydrogenase of pituitary of rat to testosterone
(Birkhäuser-Verlag, 1978) K.V. Giri; S.N. Singh
The effects of time and various doses of testosterone on the responsiveness of lactate dehydrogenase of pituitary of 7-, 38- and 78-week-old rats were studied. The activity of the enzyme increases in 78-week-old rats. Castration decreases the enzyme activity at all ages. Maximum increase in the enzyme activity is seen with 50 and 100 μg of testosterone 4 h after administration of hormone to castrated rats. No further time and dose-dependent effect is observed. The magnitude of increase for the enzyme is higher at the age of 38 weeks and decreases in 78-week-old rats. © 1978 Birkhäuser Verlag.
Age-linked alterations in fructose-2,6-bisphosphate-induced modulation of rat muscle phosphofructokinase
(1989) S.K. Triguu; S.N. Singh
Native muscle phosphofructokinase (PFK: EC 2.7.1.11) isolated from 25- and 100-week-old rats was subjected to in vitro studies on fructose-2,6-bisphosphate-induced alterations in the regulatory roles of other key metabolic modulators of this enzyme. Although fructose 2,6-bisphosphate-mediated reversal of citrate inhibition did not show any age-related difference, synergism with glucose-1,6-bisphosphate effect was found to be slightly increased with the enzyme of 100-week-old rats. In addition, apart from a significant decrease in the extent of fructose-2,6-bisphosphate activation, synergism with AMP activation and reversal of ATP and pyridoxal-5-phosphate inhibitions were observed to be decreased markedly with the enzyme of 100-week-old rats in comparison with that of 25-week-old rats. Such age-dependent alterations in muscle PFK provide evidence for conformational modification in this enzyme as a function of age.
Alterations in rat lactate dehydrogenase: Age-related comparison of M- and H-LDH
(1984) M. Prabhakaram; S.N. Singh
[No abstract available]
Alterations in the activity of glyceraldehyde-3P-dehydrogenase of the rat liver as a function of age
(Birkhäuser-Verlag, 1969) S.N. Singh; M.S. Kanungo
[No abstract available]
Alterations in the sensitivity to endogenous proteolysis due to storage of fructose-1,6-bisphosphatase extracts of liver and muscle of young and old rats.
(1987) S.K. Trigun; S.N. Singh
The sensitivity of fructose-1,6-bisphosphatase (FBPase: EC 3.1.3.11) to endogenous proteolysis was studied in liver and muscle extracts of young (28 weeks) and old (97 weeks) rats (stored at 4 degrees +/- 2 degrees C) by monitoring the alterations in its properties. Apart from the level of total enzyme activity, decrease in activity ratio (at pH 7.0/9.2) and sensitivity to AMP inhibition no age-dependent significant change was found during storage of the liver extract. However, a more significant increase in activity, comparatively less decrease in activity ratio, and retention of sensitivity to AMP inhibition were observed during the storage of muscle enzyme extract from old rats than from young rats. Using gel electrophoresis, an extra degradative active product was observed in all samples except those of old rat muscle. These results may indicate tissue-specific alterations in the susceptibility of FBPase to endogenous proteolysis during old age in the rat.
Alternation in mineral accumulation pattern of Triticum aestivum L. exposed to particulate pollution
(1983) S.N. Singh
Air pollutants influence the pattern of mineral accumulation in plants. In this experiment, wheat plants were grown in 1 m2 plots and treated with the same amount of cement dust at pre-flowering, flowering, and post-flowering stages, separately. The plants were sampled periodically and analysed for N, P, K and Ca concentrations. The observations revealed that under the influence of cement-dust pollution, the accumulation of N and P in plants declined, whereas that of K and Ca was enhanced. It was also noted that changes in mineral accumulation were more pronounced in plants subjected to cement dust at flowering stage than at pre- and post-flowering stages. © 1983.
An adjustment of a selection bias in postpartum amenorrhea from follow-up studies
(1979) S.N. Singh; B.N. Bhattacharya; R.C. Yadava
In a prospective study in which females giving birth in a specified small interval of time are followed to obtain the distribution of the duration of postpartum amenorrhea (PPA), the observed distribution involves a selection bias because of an overrepresentation of smaller PPA. In this article, the nature of this selection bias is investigated and an analytical procedure is outlined to adjust the observed distribution of PPA in order to obtain the true distribution. The proposed technique is illustrated with one set of observed data. © 1979, Taylor & Francis Group, LLC.
Analysis and Performance of a Chopper Controlled Separately Excited DC Motor
(1982) S.N. Singh; D.R. Kohli
A combination of Fourier analysis of load voltage waveform and Laplace transformation is applied for determining the performance of a separately excited dc motor fed from a chopper controlled supply, under all modes of operation. The analysis takes into account the commutation interval and the results show that contrary to the assumption made in works reported earlier, commutation interval significantly affects the performance. For the case of continuous conduction, independent expressions for current and speed are obtained in terms of applied voltage, load torque, and chopper and machine parameters. However, in the case of discontinuous conduction, Fourier coefficients include speed voltage as an additional quantity and hence the equations for current and speed have to be solved as simultaneous equations. The analysis is used to predict the steady-state and transient response. Computed torque-speed characteristics are compared with the results obtained experimentally. © 1982 IEEE
ATHENA detector proposal - a totally hermetic electron nucleus apparatus proposed for IP6 at the Electron-Ion Collider
(Institute of Physics, 2022) J. Adam; L. Adamczyk; N. Agrawal; C. Aidala; W. Akers; M. Alekseev; M.M. Allen; F. Ameli; A. Angerami; P. Antonioli; N.J. Apadula; A. Aprahamian; W. Armstrong; M. Arratia; J.R. Arrington; A. Asaturyan; E.C. Aschenauer; K. Augsten; S. Aune; K. Bailey; C. Baldanza; M. Bansal; F. Barbosa; L. Barion; K. Barish; M. Battaglieri; A. Bazilevsky; N.K. Behera; V. Berdnikov; J. Bernauer; C. Berriaud; A. Bhasin; D.S. Bhattacharya; J. Bielcik; J. Bielcikova; C. Bissolotti; W. Boeglin; M. Bondì; M. Borri; F. Bossù; F. Bouyjou; J.D. Brandenburg; A. Bressan; M. Brooks; S.L. Bültmann; D. Byer; H. Caines; M. Calderon De La Barca Sanchez; V. Calvelli; A. Camsonne; L. Cappelli; M. Capua; M. Castro; D. Cavazza; D. Cebra; A. Celentano; I. Chakaberia; B. Chan; W. Chang; M. Chartier; C. Chatterjee; D. Chen; J. Chen; K. Chen; Z. Chen; H. Chetri; T. Chiarusi; M. Chiosso; X. Chu; J.J. Chwastowski; G. Cicala; E. Cisbani; E. Cline; I. Cloët; D. Colella; M. Contalbrigo; G. Contin; R. Corliss; Y. Corrales-Morales; J. Crafts; C. Crawford; R. Cruz-Torres; D. D'Ago; A. D'Angelo; N. D'Hose; J. Dainton; S. Dalla Torre; S.S. Dasgupta; S. Dash; N. Dashyan; J. Datta; M. Daugherity; R. De Vita; W. Deconinck; M. Defurne; K. Dehmelt; A. Del Dotto; F. Delcarro; G. Dellacasa; Z.S. Demiroglu; G.W. Deptuch; V. Desai; A. Deshpande; K. Devereaux; R. Dhillon; R. Di Salvo; C. Dilks; D. Dixit; S. Dobbs; X. Dong; J. Drachenberg; A. Drees; R. Dupré; M. Durham; R. Dzhygadlo; L. El Fassi; D. Elia; E. Epple; R. Esha; O. Evdokimov; O. Eyser; D. Falchieri; W. Fan; A. Fantini; R. Fatemi; S. Fazio; S. Fegan; A. Filippi; H. Fox; A. Francisco; A. Freeze; S. Furletov; Y. Furletova; C. Gal; S. Gardner; P. Garg; D. Gaskell; K. Gates; M.T.W. Gericke; F. Geurts; C. Ghosh; M. Giacalone; F. Giacomini; S. Gilchrist; D. Glazier; K. Gnanvo; L. Gonella; L.C. Greiner; N. Guerrini; L. Guo; A. Gupta; R. Gupta; W. Guryn; X. He; T. Hemmick; S. Heppelmann; D. Higinbotham; M. Hoballah; A. Hoghmrtsyan; M. Hohlmann; T. Horn; D. Hornidge; H.Z. Huang; C.E. Hyde; P. Iapozzuto; M. Idzik; B.V. Jacak; M. Jadhav; S. Jain; C. Jena; A. Jentsch; Y. Ji; Z. Ji; J. Jia; P.G. Jones; R.W.I. Jones; S. Joosten; S. Joshi; L. Kabir; G. Kalicy; G. Karyan; V.K.S. Kashyap; D. Kawall; H. Ke; M. Kelsey; J. Kim; J. Kiryluk; A. Kiselev; S.R. Klein; H. Klest; V. Kochar; W. Korsch; L. Kosarzewski; A. Kotzinian; F. Krizek; A. Kumar; K.S. Kumar; L. Kumar; R. Kumar; S. Kumar; A. Kunnath; N. Kushawaha; R. Lacey; Y.S. Lai; K. Lalwani; J. Landgraf; L. Lanza; D. Lattuada; M. Lavinsky; J.H. Lee; S.H. Lee; R. Lemmon; A. Lestone; N. Lewis; H. Li; S. Li; W. Li; W. Li; X. Li; X. Li; X. Liang; T. Ligonzo; T. Lin; J. Liu; K. Liu; M. Liu; K. Livingston; N. Liyanage; T. Ljubicic; O. Long; N. Lukow; Y. Ma; J. Mammei; F. Mammoliti; K. Mamo; I. Mandjavidze; S. Maple; D. Marchand; A. Margotti; C. Markert; P. Markowitz; T. Marshall; A. Martin; H. Marukyan; A. Mastroserio; S. Mathew; S. Mayilyan; C. Mayri; M. McEneaney; Y. Mei; L. Meng; F. Méot; J. Metcalfe; Z.-E. Meziani; P. Mihir; R. Milton; A. Mirabella; M. Mirazita; A. Mkrtchyan; H. Mkrtchyan; B. Mohanty; M. Mondal; A. Morreale; A. Movsisyan; D. Muenstermann; A. Mukherjee; C. Munoz Camacho; M.J. Murray; H. Mustafa; M. Myška; B.P. Nachman; K. Nagai; R. Naik; J.P. Naim; J. Nam; B. Nandi; E. Nappi; Md. Nasim; D. Neff; D. Neiret; P.R. Newman; M. Nguyen; S. Niccolai; M. Nie; F. Noferini; J. Norman; F. Noto; A.S. Nunes; T. O'Connor; G. Odyniec; V.A. Okorokov; M. Osipenko; B. Page; C. Palatchi; D. Palmer; P. Palni; S. Pandey; D. Panzieri; S. Park; K. Paschke; C. Pastore; R.N. Patra; A. Paul; S. Paul; C. Pecar; A. Peck; I. Pegg; C. Pellegrino; C. Peng; L. Pentchev; R. Perrino; K. Piotrzkowski; T. Polakovic; M. Płoskoń; M. Posik; S. Prasad; R. Preghenella; S. Priens; E. Prifti; M. Przybycien; P. Pujahari; A. Quintero; M. Radici; S.K. Radhakrishnan; S. Rahman; S. Rathi; B. Raue; R. Reed; P. Reimer; J. Reinhold; E. Renner; L. Rignanese; M. Ripani; A. Rizzo; D. Romanov; A. Roy; N. Rubini; M. Ruspa; L. Ruan; F. Sabatié; S. Sadhukhan; N. Sahoo; P. Sahu; D. Samuel; A. Sarkar; M. Sarsour; W. Schmidke; B. Schmookler; C. Schwarz; J. Schwiening; M. Scott; I. Sedgwick; M. Segreti; S. Sekula; R. Seto; N. Shah; A. Shahinyan; D. Sharma; N. Sharma; E.P. Sichtermann; A. Signori; A. Singh; B.K. Singh; S.N. Singh; N. Smirnov; D. Sokhan; R. Soltz; W. Sondheim; S. Spinali; F. Stacchi; R. Staszewski; P. Stepanov; S. Strazzi; I.R. Stroe; X. Sun; B. Surrow; Z. Sweger; T.J. Symons; V. Tadevosyan; A. Tang; E. Tassi; L. Teodorescu; F. Tessarotto; D. Thomas; J.H. Thomas; T. Toll; L. Tomášek; F. Torales-Acosta; P. Tribedy; Triloki; V. Tripathi; R. Trotta; M. Trzebiński; B.A. Trzeciak; O. Tsai; Z. Tu; R. Turrisi; C. Tuvè; T. Ullrich; G.M. Urciuoli; A. Valentini; S. Vallarino; M. Vandenbroucke; J. Vanek; G. Vino; G. Volpe; H. Voskanyan; A. Vossen; E. Voutier; G. Wang; Y. Wang; D. Watts; N. Wickramaarachchi; F. Wilson; C.-P. Wong; X. Wu; Y. Wu; J. Xie; Q.-H. Xu; Z. Xu; Z.W. Xu; C. Yang; Q. Yang; Y. Yang; Z. Ye; Z. Ye; L. Yi; Z. Yin; M. Yurov; N. Zachariou; J. Zhang; Y. Zhang; Z. Zhang; Z. Zhang; Y. Zhao; Y.X. Zhao; Z. Zhao; L. Zheng; M. Żurek
ATHENA has been designed as a general purpose detector capable of delivering the full scientific scope of the Electron-Ion Collider. Careful technology choices provide fine tracking and momentum resolution, high performance electromagnetic and hadronic calorimetry, hadron identification over a wide kinematic range, and near-complete hermeticity. This article describes the detector design and its expected performance in the most relevant physics channels. It includes an evaluation of detector technology choices, the technical challenges to realizing the detector and the R&D required to meet those challenges. © 2022 The Author(s).
Bilateral generating functions for a new class of generalized legendre polynomials
(1980) A.N. Srivastava; S.D. Singh; S.N. Singh
Recently Chatterjea (1) has proved a theorem to deduce abilateral generating function for the Ultraspherical polynomials. In the present paper an attempt has been made to give a general version of Chatterjea1s theorem. Finally the theorem has been specialized to obtain a bilateral generating function for a class of polynomials {Pn (zx; a,8)} introduced by Bhattacharjya (2). © 1980, Hindawi Publishing Corporation. All rights reserved.