Browsing by Author "Vivek Tiwari"

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Amalaki Rasayana improved memory and neuronal metabolic activity in AβPP-PS1 mouse model of Alzheimer’s disease
(Springer India, 2017) Vivek Tiwari; Kamal Saba; Pandichelvam Veeraiah; Jedy Jose; Subhash C Lakhotia; Anant B Patel
Alzheimer’s disease (AD) is the most common neurodegenerative disorder characterized by progressive loss of memory and cognitive function. The cerebral metabolic rate of glucose oxidation has been shown to be reduced in AD. The present study evaluated efficacy of dietary Amalaki Rasayana (AR), an Ayurvedic formulation used in Indian traditional system, in AβPP-PS1 mouse model of AD in ameliorating memory and neurometabolism, and compared with donepezil, a standard FDA approved drug for AD. The memory of mice was measured using Morris Water Maze analysis. The cerebral metabolism was followed by 13C labelling of brain amino acids in tissue extracts ex vivo using 1H-[13C]-NMR spectroscopy together with a short time infusion of [1,6-13C2]glucose to mice. The intervention with Amalaki Rasayana showed improved learning and memory in AβPP-PS1 mice. The 13C labelings of GluC4, GABAC2 and GlnC4 were reduced in AβPP-PS1 mice when compared with wild-type controls. Intervention of AR increased the 13C labelling of amino acids suggesting a significant enhancement in glutamatergic and GABAergic metabolic activity in AβPP-PS1 mice similar to that observed with donepezil treatment. These data suggest that AR has potential to improve memory and cognitive function in AD. © 2017, Indian Academy of Sciences.
An improved volume power approach to estimate LAI from optimized dual-polarized SAR decomposition
(Taylor and Francis Ltd., 2023) Shubham Kumar Singh; Rajendra Prasad; Vivek Tiwari; Prashant K Srivastava
Synthetic Aperture Radar (SAR) imagery has proven to be a valuable tool for monitoring the Earth’s surface, particularly vegetation. However, many studies using SAR have focused solely on backscattering sensitivity without considering the structural and physical properties of the vegetation being analysed. This study proposes a new approach for vegetation monitoring using the Volume Power (VP) analysis technique. The proposed method aims to improve the accuracy of VP derived from the Freeman-Durden (FD) decomposition technique for dual polarimetric SAR data. To increase the sensitivity of vegetation scattering in SAR analysis, this study modified the VP using Depolarized Volume Power (DVP) and Anisotropic Volume Power (AVP). The first modification, DVP, was achieved by incorporating the degree of polarization ((Formula presented.)) in the analysis. The second modification, AVP, is achieved by considering the anisotropic scattering properties of vegetation. The modified VP is then used to estimate Leaf Area Index (LAI) using an empirical relationship between LAI and the modified VPs. The accuracy of the LAI estimation is evaluated using ground truth measurements. The results demonstrate that the proposed method provides more accurate LAI estimates than traditional methods. The approach also shows improved sensitivity to vegetation scattering compared to the original VP from the FD, indicating the effectiveness of the degree of polarization and anisotropic scattering in reducing the impact of unwanted scattering mechanisms from the surface. The accuracy (R 2) between in-situ LAI and the LAI retrieved from AVP and DVP was 0.85 and 0.82, whereas for FDVP, it was 0.74. These findings highlight the potential of the proposed approach for improving the accuracy of VP estimation in dual-polarimetric SAR data and enabling more accurate and efficient estimation of LAI. © 2023 Informa UK Limited, trading as Taylor & Francis Group.
Energetics of excitatory and inhibitory neurotransmission in aluminum chloride model of alzheimer’s disease: Reversal of behavioral and metabolic deficits by rasa sindoor
(Frontiers Media S.A., 2017) Kamal Saba; Niharika Rajnala; Pandichelvam Veeraiah; Vivek Tiwari; Rohit K. Rana; Subhash C. Lakhotia; Anant B. Patel
Alzheimer’s disease (AD) is an age-related neurodegenerative disorder, characterized by progressive loss of cognitive functions and memory. Excessive intake of aluminum chloride in drinking water is associated with amyloid plaques and neurofibrillary tangles in the brain, which are the hallmark of AD. We have evaluated brain energy metabolism in aluminum chloride (AlCl3) mouse model of AD. In addition, effectiveness of Rasa Sindoor (RS), a formulation used in Indian Ayurvedic medicine, for alleviation of symptoms of AD was evaluated. Mice were administered AlCl3 (40 mg/kg) intraperitoneally once a day for 60 days. The memory of mice was measured using Morris Water Maze test. The 13C labeling of brain amino acids was measured ex vivo in tissue extracts using 1H-[13C]-NMR spectroscopy with timed infusion of [1,6-13C2]glucose. The 13C turnover of brain amino acids was analyzed using a three-compartment metabolic model to derive the neurotransmitter cycling and TCA cycle rates associated with glutamatergic and GABAergic pathways. Exposure of AlCl3 led to reduction in memory of mice. The glutamatergic and GABAergic neurotransmitter cycling and glucose oxidation were found to be reduced in the cerebral cortex, hippocampus, and striatum following chronic AlCl3 treatment. The perturbation in metabolic rates was highest in the cerebral cortex. However, reduction in metabolic fluxes was higher in hippocampus and striatum following one month post AlCl3 treatment. Most interestingly, oral administration of RS (2 g/kg) restored memory as well as the energetics of neurotransmission in mice exposed to AlCl3. These data suggest therapeutic potential of RS to manage cognitive functions and memory in preclinical AD. © 2017 Saba, Rajnala, Veeraiah, Tiwari, Rana, Lakhotia and Patel.
Evaluation of groundwater quality of Prayagraj city using entropy water quality index (EWQI) and new integrated water quality index (IWQI)
(Springer Science and Business Media Deutschland GmbH, 2022) Upma Gautam; Vivek Tiwari; Vinod Kumar Tripathi
Information about groundwater quality and their suitability for drinking purpose is important for the society. Two indices namely entropy water quality index (EWQI) and new integrated water quality index (IWQI) have been used to assess the groundwater quality of Prayagraj city, India. The synthesis of outcomes is presented through geographical information system (GIS). Fifteen groundwater quality parameters namely pH, electrical conductivity, hardness, total dissolved solids, alkalinity, calcium, sodium, magnesium, potassium, nitrate, bicarbonate, chloride, sulphate, fluoride and iron were evaluated during pre- and post-monsoon season. It is revealed that the groundwater in the city is good and hard type with excess concentration of iron. On the basis of EWQI, groundwater is good and suitable for drinking purposes both in pre- and post-monsoon period. IWQI has resulted that during pre-monsoon water quality in 17% of the area is unsuitable for drinking with 25% area having poor water quality but during post-monsoon, the same area has been increased to 25% and 42%, respectively. About 50% of the area is categorised as marginal quality water during pre-monsoon but it is reduce to 33% during post-monsoon. Present study suggests the requirement for regular assessment of groundwater quality for its healthier utilization and management. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
Groundwater quality assessment of Allahabad smart city using GIS and water quality index
(Springer Science and Business Media Deutschland GmbH, 2020) H.K. Pandey; Vivek Tiwari; Saurabh Kumar; Aniket Yadav; S.K. Srivastava
Groundwater quality plays a very important role in groundwater protection as well as demarcation of the groundwater depleted area which may be attempted for its improvement and conservation. An effort has been made to comprehend the water quality of Allahabad city with the help of groundwater sampling, their chemical analysis, and synthesis of results in GIS framework. The assessment of physiochemical parameters of groundwater samples for drinking purpose has been made using Water Quality Index and Geographic Information System. Spatial distribution of pH, electrical conductivity, total dissolved solids, fluoride, iron, total alkalinity, total hardness, chloride, sulphate, sodium, potassium, calcium, magnesium, bicarbonate, and nitrate content of groundwater samples collected from 12 locations and studied for pre-monsoon (May 2016) and post monsoon (Nov 2017) periods has been assessed using Arc-GIS. Water quality maps of pre-monsoon period reveal that 4.23% area is falling under good, 74.82% under moderate, and 12.12% under poor and 0.66% under very poor category while water quality maps for post monsoon period reveal that the 40.33% of area falls under good, 58.89% area under moderate and 0.77% under poor water quality. The observed values of various physiochemical parameters of water samples were also compared with standard values recommended by IS 10,500:2012. It is observed that depth to water has positive correlation with TDS, electrical conductivity, and hardness. The extent of pollution occurred in the city is due to over exploitation of groundwater, urbanization, and anthropogenic activities. © 2020, Springer Nature Switzerland AG.
Moderation effect of Job Involvement on the relationship between Organizational Commitment and Job Satisfaction
(SAGE Publications Inc., 2014) Vivek Tiwari; S.K. Singh
The present study investigates the impact that Job Satisfaction (JS) has on the Organizational Commitment (OC) level of industrial workers and also finds out whether Job Involvement (JI) moderates the relationship between JS and OC. The study has been conducted on 600 employees belonging to different departments of Diesel Locomotive Works (DLW), which is one of the public sector giants of India. Relationship between JS and OC has been established with the help of a 2 × 2 factorial design, and moderation effect of JI on the relationship between JS and OC has been checked with the help of hierarchical multiple regression analysis. The results of the investigation have come out with the findings that OC is positively related to JS. Also, JI does moderate the relationship between JS and OC but in a negative way, and the impact has been found to be weak. © The Author(s) 2014.
Relationship among work- related micro-ob variables: A model approach
(IGI Global, 2017) Vivek Tiwari; Surendra Kumar Singh
The present study investigates the nature of job involvement and its impact on executive's satisfaction level in providing motivation finally leading to organizational commitment. A model has been developed which examines the relationship between the measurable constructs. The model explores the relationship between the executive's job involvement level and their outcome with satisfaction level, motivation and organizational Commitment (named ISMC Model). The results indicate there is a goodness-of-fit for the research model, which has been verified with different measures of goodness-of-fit. The path coefficients explained a significant amount of variation along with the identification that job involvement is a significant attribute in the present model. The study examines executive's perceptions and the significance of job involvement. Management specialists will recognize the dynamics of job involvement and its linkage with job satisfaction, motivation and organizational commitment in an organization. © 2017 by IGI Global. All rights reserved.
Role of occupational stress to the relationship between job satisfaction and organizational commitment
(School of Management Sciences, 2016) Vivek Tiwari; S.K. Singh
Stress, the word whenever strikes the mind is usually interpreted in negative terms though in practice stress as a variable can be a good motivator if present only to a certain level (eustress), but when it crosses that minimum required limit and turns into distress, it may cause an employee loose interest in the job and hence reduce the job satisfaction level and hence may result into a lesser commitment to organization. It may even become such a big de-motivator that can even reduce the energy and zeal of an employee to even work any further. Thus this study is an attempt in finding out the relationship that organizational commitment shares with job satisfaction and the impact that occupational stress has on the relationship. © 2016, School of Management Sciences. All rights reserved.