Browsing by Author "A.K. Tiwari"

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An indirect technique for estimations of infant and child mortality: Data analysis from India and Bangladesh
(2003) R.C. Yadava; A.K. Tiwari
The analysis of mortality data is of vital interest to policy planners and health administrators in the formulation of development strategies to meet the health needs and demands of people and also in the implementation and evaluation of public health programmes. The study of child mortality provides useful information on the current demographic situation in that region and indicates on the prospects of potential change in future. Death is a vital event recorded through the system of civil registration. But in developing countries, quality of registered data is not very much reliable because of its failure to reach to all groups of the population affected by illiteracy and ignorance. Because of many unreliable estimates arising out of the civil registration system, exploration of indirect techniques for estimating vital indicators has become a necessity. In the present study, we have utilized an indirect technique for estimating infant mortality and under-five mortality rates by using the data of mean number of children ever born and living to currently married women aged 15-49 years. The method is essentially based on the technique of regression line analysis taking infant mortality rate or under five-mortality rate as a dependent variable and the proportion of dead children among the total children born to currently married females (15-49 years) as independent variable. The regression line analysis was computed and tested using data from National Family Health Survey (India) and Demographic and Health Survey (Bangladesh). The observed and expected rates computed from regression line were found overlapping in most cases showing complete adequacy of the proposed indirect method.
Analysis of Forest Land-use and Vegetation in a Part of Central Himalaya, Using Aerial Photographs
(1987) A.K. Tiwari; J.S. Singh
[No abstract available]
B2 kinin receptors mediate the Indian red scorpion venom-induced augmentation of visceral reflexes via the nitric oxide cyclic guanosine monophosphate pathway
(2009) S. Kanoo; A.B. Alex; A.K. Tiwari; S.B. Deshpande
Aim: This study was performed to delineate the kinin (receptor)-dependent pathways in the Indian red scorpion (Mesobuthus tamulus; MBT) venom-induced pulmonary oedema as well as the augmentation of cardio-pulmonary reflexes evoked by phenyldiguanide (PDG). Methods: In urethane-anaesthetized adult rats, the effect of venom on the PDG reflex responses (blood pressure, heart rate and respiration rate) and the pulmonary water content was ascertained using various antagonists(des- Arg, B1 receptor antagonist; Hoe 140, B2 receptor antagonist; Nω-nitro-l-arginine methyl ester (l-NAME), nitric oxide (NO) synthase inhibitor; methylene blue, soluble guanylate cyclase inhibitor; and glibenclamide, K+ATP channel blocker). The effect of phosphodiesterase V inhibitor (sildenafil citrate) on the reflex response and the pulmonary water content was also examined and compared with venom-induced responses. Results: Intravenous injection of PDG (10 μg kg -1) evoked apnoea, bradycardia and hypotension lasting >60 s. Exposure to MBT venom (100 μg kg-1) for 30 min augmented the PDG reflex responses by two times and increased the pulmonary water content, significantly. Hoe 140 blocked the venom-induced responses (augmentation of PDG reflex and increased pulmonary water content) whereas des-Arg did not. l-NAME, methylene blue or glibenclamide also blocked the venom-induced responses. Furthermore, sildenafil citrate (that increases cGMP levels) produced augmentation of PDG reflex response and increased the pulmonary water content as seen with venom. Conclusion: The results indicate that venom-induced responses involve B2 kinin receptors via the NO-dependent guanylate cyclase-cGMP pathway involving K+ATP channels. © 2009 Scandinavian Physiological Society.
Beneficial effect of an indigenous herbomineral formulation 'Abana' on hyperlipidemic rabbits
(1990) A.K. Tiwari; J.D. Gode; G.P. Dubey
[No abstract available]
Changes in forest cover in a Central Himalayan catchment: Inadequacy of assessment based on forest area alone
(Academic Press, 1997) S.K.S. Rathore; S.P. Singh; J.S. Singh; A.K. Tiwari
The Central Himalayan region experiences severe ecological problems as a result of continuous deforestation, which threatens the subsistence population of the region. In the present study, changes in the forest cover of a catchment over a period of 16 years have been quantified. Baliya catchment (7783 ha) contains 2865.47 ha of different types of forest, i.e. sal (Shorea robusta), mixed sal, pine (Pinus roxburghii), pine-mixed broadleaf, mixed oak (Quercus spp.), cupressus (Cupressus torulosa). The process of fragmentation has been studied through changes in forest area and biomass. There has been a sharp decline in biomass, although only a marginal reduction in forest area (3.5%) has occurred. Decline in the stocking density has also been substantial. Forest area with higher crown cover (> 60%) declined from 736.32 ha to 292 ha during 1971-1989, indicating the intensity of human interference.
Combined effect of magnetic field and ramped temperature in a porous medium bounded by a vertical wall
(International Information and Engineering Technology Association, 2009) A.K. Tiwari
The unsteady hydromagnetic free convective flow of an incompressible and electrically conducting fluid through a porous medium bounded by a vertical wall has been considered. It is assumed that the bounding wall has a ramped temperature profde with respect to time and fluid flow is taken under the influence of a transverse magnetic field fixed relative to this wall. Under the usual Boussinesq approximation, an exact solution for the fluid velocity is obtained with the help of the Laplace transform technique. The effects of magnetic field and permeability parameters on the fluid velocity under two different expressions in which one is valid for the fluids of Prandtl numbers greater than unity and other for Prandtl number equal to unity have been shown graphically. It is observed that the velocity profiles are greater in case of wall having isothermal temperature than ramped temperature for each parameter. We have also observed that the skin friction is less in case of wall having ramped temperature than isothermal temperature.
Different classes ratio and laplace summation operator based intuitionistic fuzzy rough attribute selection
(University of Sistan and Baluchestan, 2021) S. Shreevastava; S. Singh; A.K. Tiwari; T. Som
In real-world data deluge, due to insignificant information and high dimension, irrelevant and redundant attributes reduce the ability of experts both in predictive accuracy and speed, respectively. Attribute selection is the notion of selecting those attributes that are essential as well as enough to specify the target knowledge preferably. Fuzzy rough set-based approaches play a crucial role in selecting relevant and less redundant attributes from a high-dimensional dataset. Intuitionistic fuzzy set-based approaches can handle uncertainty as it gives an additional degree of freedom when compared to fuzzy approaches. So, it has a more flexible and practical ability to deal with vagueness and noise available in the information system. In this paper, we introduce two new robust approaches for attribute selection based on intuitionistic fuzzy rough set theory using the concepts of Different Classes ratio and Laplace Summation operator. Firstly, Different Classes ratio and Laplace Summation operator based lower and upper approximations are established based on intuitionistic fuzzy rough set concept. Moreover, we present algorithms and illustrative examples for a better understanding of our approaches. Finally, experimental analysis is performed on some real-valued datasets for attribute selection and classification accuracies. © 2021, University of Sistan and Baluchestan. All rights reserved.
Effect of Temperature Dependent Sink on Peristaltic Transport in a Differentially Heated Vertical Annulus Filled with a Porous Material
(Taylor and Francis Ltd., 2022) A.K. Tiwari; A.K. Singh
In this article, we have presented a mathematical analysis to study the peristaltic flow through vertical annulus filled with a porous material bounded by two concentric uniform tubes. This analysis can serve as a model which may help in understanding the mechanism of physiological flows and heat transfer in a vertical annulus subject to differentially heating in the presence of a temperature dependent sink. The inner tube is uniform and rigid, while the outer tube has a sinusoidal wave traveling down its wall. It is analyzed in a wave frame of reference moving with velocity of the wave under a zero Reynolds number and long wavelength approximation in the presence of a temperature dependent sink. The analytical solutions are obtained for temperature, axial velocity, stream function and axial pressure-gradient. We also present numerical integration in order to analyze the pressure rise and frictional forces on the inner and outer tubes. In order to have an estimate of the quantitative effects of various emerging physical parameters on flow characteristics which are involved in the solutions of the considered analysis, we have used the MATLAB software for plotting the contour graphs and discussed in details. We have observed that the intensity of heat sink increases when amplitude ratio is increased. The trapped bolus appears when Darcy number is small but the important observation is that for the large values of Darcy number, the trapped bolus disappears and fluid moves like a block, which shows some sort of rigidity. © 2022 Taylor & Francis Group, LLC.
Effect of terminalia arjuna on lipid profiles of rabbits fed hypercholesterolemic diet
(1990) A.K. Tiwari; J.D. Gode; G.P. Dubey
[No abstract available]
Effect of terminalia arjuna on lipid profiles of rabbits fed hypercholesterolemic diet
(Informa Healthcare, 1990) A.K. Tiwari; J.D. Gode; G.P. Dubey
Rabbits Receiving Terminalia Arjuna Along With A High Cholesterol Diet Showed Lesser Increase In Total Cholesterol (P <0.01) and Triglycerides (P < 0.05) and No Change In High Density Lipoprotein Cholesterol Than The Rabbits Receiving Only High Cholesterol Diet. Hypercholesterolemic Rabbits Receiving Terminalia Arjuna Treatment Showed A More Marked Reduction In Total Cholesterol (P <0.02) and Triglycerides (P <0.05) and Elevation In High Density Lipoprotein Cholesterol (P <0.001) Than The Hypercholesterolemic Control Rabbits. © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.
FERTILITY PATTERN IN INDIA AND ESTIMATION OF TOTAL FERTILITY RATE
(DAV College, 2021) A.K. Tiwari; Shivam Mishra
The fertility of India has decreased steadily over the years due to various determining factors but the most important aspect of fertility is that it is much more the subject of individual choice. Hence, when fertility starts to decline, it would be expected that the main changes are due to be parity specific which occurred with a reduction of higher-order births. The authors have attempted to analyse the fertility changes in India by analysing Period Parity Progression Ratios (PPPRs) for each parity transition and transition from birth to marriage also. Then the total fertility rates for all the major states of India in the year 1991 and 2014 have been estimated by using PPPRs. For this study, the birth history information of females has been obtained from the National Family Health Survey (NFHS) dataset. Findings show that the fertility of India has been declined over the years from 1982 to 2014. There is no significant change in the proportions of females having higher order births, but a sharp decline has been observed for the parity transition between second parity to third parity, and third parity to fourth parity. The progression of females is also influenced by their socio-economic and educational status. There is observed a tendency in the increment of age at first marriage of females from 1991 to 2014. © 2021 DAV College. All rights reserved.
Geo-forestry of Landslide-affected Areas in a Part of Central Himalaya
(1986) A.K. Tiwari; J.S. Mehta; O.P. Goel; J.S. Singh
[No abstract available]
Himalayan Forests: A Net Source of Carbon for the Atmosphere
(1985) J.S. Singh; A.K. Tiwari; A.K. Saxena
[No abstract available]
Identification of a novel pulmonary oedema producing toxin from Indian red scorpion (Mesobuthus tamulus) venom
(Elsevier Ltd, 2005) S.B. Deshpande; A.B. Alex; M.V. Jagannadham; G.R.K. Rao; A.K. Tiwari
The experiments were conducted to identify the toxin that produces pulmonary oedema in Mesobuthus tamulus (BT) envenomed animals. Crude BT venom was subjected to Sephadex gel filtration (G-75) and the fractions were screened for optical density (OD), neurotoxicity (prolongation of compound action potential in frog sciatic nerve) and lethality. All these parameters exhibited a peak between 54-94 ml eluates. Fractions of this peak were pooled (SP) and loaded on to carboxymethyl cellulose column. The column was then eluted with increasing buffer concentrations at constant pH and temperature. Eluates were screened for neurotoxicity and OD. Four peaks of neurotoxic activity (T1-T4) were detected. T2 and T3 were lethal whereas T1 and T4 were non-lethal. T2 exhibited mainly neurotoxicity and failed to augment phenyldiguanide (PDG)-induced reflex response or to produce pulmonary oedema. T3 was having minimal neurotoxic actions but augmented PDG-reflex and produced pulmonary oedema. The effects of T3 persisted even after dialysis with 8 kDa cut-off filter but not those of T2. The T3 effects resembled toxic manifestations of BT venom and were blocked by aprotinin pre-treatment. T3 demonstrated a band at ∼100 kDa in SDS-PAGE. The results demonstrate the presence of a lethal, high molecular weight, pulmonary oedema producing toxin in BT venom. © 2005 Elsevier Ltd. All rights reserved.
In-vitro contractility of normal human vermiform appendix involves 5-hydroxytryptamine (5-HT3) pathways in addition to muscarinic transmission
(Research Journal of Pharmaceutical, Biological and Chemical Sciences, 2016) P.B. Singh; A.K. Tiwari; S. Basu; A. Ghosh Kar; A. Akella; Shripad B. Deshpande
Appendicitis is a cause of health concern in all age and sex worldwide. Alteration in appendicular peristalsis/contractility has been implicated as a precipitating factor in appendicitis. But, the neurotransmitters involved in the contractility of normal human vermiform appendix are not well understood. The present study was undertaken to investigate the neurotransmitter mediated pathways involved in mediating the contractility of longitudinal muscles of normal human vermiform appendix. Longitudinal muscle strips of human vermiform appendix were mounted in Dale's organ bath. In vitro contractility to agonist was recorded using Statham's isometric force displacement transducer. Experiments were performed to determine the dose-response of agonists (acetylcholine/5-HT/ histamine) and the dose that produced maximum contractions. In a separate set of experiments, the effect of antagonists (like atropine, ondansetron and chlorpheniramine maleate) on the agonist-induced contractions was evaluated. Acetylcholine (ACh) and 5-HT produced dose-dependent increase in contractions. ACh produced maximum contractions at 10 μM and it was partially (70%) but significantly blocked (p < 0.05) by atropine (100 μM) pretreatment. 5-HT produced maximum contractions at 1 μM and it was blocked (p < 0.05) by 5-HT3 antagonist, ondansetron (10μM). The contractions produced by histamine were small, hence effect of histamine antagonist on histamine induced contractions were not analyzed. Thus, the present study suggests the involvement of 5-HT3 pathway in addition to cholinergic-muscarinic transmission in mediating the contractility of normal human appendix. Histamine plays a minor role in overall contractility of normal appendix.
Managing riparian zones for river health improvement: an integrated approach
(Springer Japan, 2021) Rinku Singh; A.K. Tiwari; G.S. Singh
Riparian zones are among the most valuable ecosystems on the earth. They act as the ecological engineers that improve river health through delivering a range of ecosystem functions. Stream bank stabilization, pollutant and sediment buffering, temperature regulation, provision of energy to river food webs and communities, groundwater recharge and provision of ecological corridors and habitat for wildlife, are among major ecosystem functions of riparian zones that play a great role in river health. Besides these ecosystem functions, riparian zones also provide various ecosystem goods and services for human well-being. But in the current scenario, riparian zones are under severe threat due to agricultural activities, urbanization, river flow alteration, overexploitation, climate change, pollution, and biological invasion. In the present and probable future scenarios of declining river health and global environmental changes, there is a pressing need of an integrated approach for managing riparian zones. This review article aims to advocate an integrated approach for riparian zone management based on various components such as riparian condition assessment, policy framework, stakeholder’s participation, management practices, legislation, and awareness. Authors also discussed riparian zones in context of their concepts, features, functions, and threats. © 2021, International Consortium of Landscape and Ecological Engineering.
Measurement of inequality and study of social influence on distribution of land holding in india
(DAV College, 2020) A.K. Tiwari; Shivam Mishra; Ravi Kant Maurya
In the Indian economic scenario, the primary sector or agriculture-related sector is the major source of national income, and it shares around 18% of India's GDP. Although around 40 percent workforce of the country is employed in this sector, the productivity is relatively at a low level.The unequal and staggered distribution of land leads to the low productivity in agriculture. Inequality in the land distribution is defined as the differences in the size of land holdings possessed by various individuals or households. It is known that the size of landholdings varies from household to household. The widely used measure of inequality i.e. Gini's coefficient has been applied in this study by using NFHS India datasets. In this study, it is observed that the proportion of landless population has increased continuously in the country especially in the states where major population has involved intensely in the agricultural works. © 2020 DAV College. All rights reserved.
MHD flow of a micropolar fluid with asymmetric wall temperatures
(Nova Science Publishers, Inc., 2012) S.K. Ravi; A.K. Tiwari; R.K. Singh
This paper presents the effect of MHD of micropolar fluids with asymmetric wall temperatures in a vertical wall. The transformed boundary layer governing equations are solved by the Matlab software. The dynamic of micropolar fluids has been a popular area of research. As the fluid consist of randomly oriented molecules, and as each volume element of the fluid have translated as well as rotation. The analysis of physical problems in these fluids has revealed several interesting phenomena, which are not found in Newtonian fluids. Increasing the Magnetohydrodynamics parameter tends to decrease the velocity profile while the micro rotation increase as the Magnetohydrodynamics increases in vertical walls. © 2012 Nova Scicence Publishers, Inc. All rights reserved.
Monsoon-influenced variations in productivity and lithogenic flux along offshore Saurashtra, NE Arabian Sea during the Holocene and Younger Dryas: A multi-proxy approach
(Elsevier B.V., 2017) Syed Azharuddin; Pawan Govil; A.D. Singh; Ravi Mishra; Shailesh Agrawal; A.K. Tiwari; Kamlesh Kumar
A sediment core from NE Arabian Sea was studied to reveal the variations in shelf environment of western continental margin of India. A multi-proxy analysis based on planktonic foraminifera abundance (PFA), benthic foraminifera abundance (BFA), planktonic-benthic foraminiferal ratio (P/B), CaCO3 percentage (wt%), Oxygen (δ18OG. ruber) and Carbon (δ18OG. ruber) isotopes of foraminifera as well as sediment X-ray studies were carried out on 3.4 m long core SK-240/485 recovered from offshore Saurashtra, NE Arabian Sea. The study aims to understand the monsoon variability in the NE Arabian Sea offshore Saurashtra since the late Pleistocene-Holocene transition and how monsoon climate coupled with sea-level change influenced paleo-productivity pattern. Six AMS radiocarbon dates place the core in the time interval 12–1 Ka. Our study reveals that there have been three periods of major changes in the monsoonal climate, productivity and sea level; viz. 12–8 Ka (Younger Dryas and early Holocene); 8–4 Ka (middle Holocene) and 4–1 Ka (late Holocene). The studied time period was also marked by weakened south west monsoon (SWM) during the cold events such as Younger Dryas (YD), Abrupt Event (AE) centring around 9.8 Ka as well as 8.2 and 4 Ka cold events. The Younger Dryas and early Holocene shows the low sea level stand and less Indus river discharge. Thereafter during middle and late Holocene the monsoon strengthened which resulted in raised sea level and increased Indus river discharge. The proxy records broadly suggest relatively low foraminiferal productivity at the core location during the Younger Dryas and early Holocene. We record a moderate foraminiferal productivity during the middle Holocene between 8 and 4 Ka, which suggest the mesotrophic condition. The foraminiferal productivity however was relatively high since 4 Ka suggesting the eutrophic conditions at the core site. © 2016 Elsevier B.V.
Natural convection in a cavity with a sloping upper surface filled with an anisotropic porous material
(2012) A.K. Tiwari; A.K. Singh; P. Chandran; N.C. Sacheti
Steady natural convection in a viscous incompressible fluid flowing in a vertical permeable non-rectangular cavity is considered. The permeability of the porous medium and the thermal diffusivity of the fluid are assumed to be anisotropic in nature. Using the Boussinesq approximation and the Darcy law to model the porous medium, the governing equations-recast in terms of a stream function-are solved numerically. An algebraic grid generation technique is employed to transform the non-rectangular domain to a square domain. The influence of a number of parameters, arising due to geometrical and physical aspects, is discussed in relation to the flow and heat transfer. © 2011 Springer-Verlag.