Indian Agricultural Statistics Research Institute

About: Indian Agricultural Statistics Research Institute is a facility organization based out in New Delhi, India. It is known for research contribution in the topics: Population & Small area estimation. The organization has 454 authors who have published 870 publications receiving 7987 citations.

Outlier Robust Small Area Estimation

Abstract: Recently proposed outlier robust small area estimators can be substantially biased when outliers are drawn from a distribution that has a different mean from that of the rest of the survey data. This naturally leads down to the idea of an outlier robust bias correction for these estimators. In this paper we develop this idea and also propose two different analytical mean squared error estimators for the ensuring bias corrected outlier robust estimators. Simulations based on realistic outlier contaminated data show that the proposed bias correction often leads to more efficient estimators. Furthermore the proposed mean squared error estimators appear to perform well with a variety of outlier robust smal area estimators.

Investigation of heavy metals in frequently utilized medicinal plants collected from environmentally diverse locations of north western India.

Abstract: The increasing prevalence of environmental pollution, especially soil contamination with heavy metals has led to their uptake in the human food chains through plant parts. Accumulation and magnification of heavy metals in human tissues through consumption of herbal remedies can cause hazardous impacts on health. Therefore, chemical profiling of nine heavy metals (Mn, Cr, Pb, Fe, Cd, Co, Zn, Ni and Hg) was undertaken in stem and leaf samples of ten medicinal plants (Acacia nilotica, Bacopa monnieri, Commiphora wightii, Ficus religiosa, Glycyrrhiza glabra, Hemidesmus indicus, Salvadora oleoides, Terminalia bellirica, Terminalia chebula and Withania somnifera) collected from environmentally diverse regions of Haryana and Rajasthan states in North-Western India. Concentration of all heavy metals, except Cr, was within permissible limits in the tested stem and leaf samples. Leaf samples had consistently more Cr compared to respective stem samples with highest concentration in leaf samples of Bacopa monnieri (13.19 ± 0.0480 ppm) and stem samples of Withania somnifera (4.93 ± 0.0185 ppm) both collected from Bahadurgarh (heavy industrial area), Haryana. This amount was beyond the permissible limit of 2.0 ppm defined by WHO for raw herbal material. Other two most perilous metals Pb (2.64 ± 0.0260) and Cd (0.04 ± 0.0274) were also recorded in Bahadurgarh region, although below permissible limits. Concentration of Hg remained below detectable levels in all the leaf and stem samples tested. These results suggested that cultivation of medicinal plants and other dietary herbs should be curtailed near environmentally polluted especially industrial areas for avoidance of health hazards.

Significance of FRAP, DPPH, and CUPRAC assays for antioxidant activity determination in apple fruit extracts

Abstract: Thirteen apple cultivars were analyzed for their total phenolic content, total flavonoids, anthocyanins, ascorbic acid in methanolic extracts of both peel and cortex fractions. Three in vitro assays (FRAP, DPPH, and CUPRAC) were used to determine the antioxidant activity. Concentration of the phytochemicals studied varied greatly between the apple peel and the cortex region. Peels showed ~ 2.8 times higher total phenolic content and ~ 2.68% higher flavonoid content than the cortex. Principal component analysis could successfully explain 76.86% and 84.27% variability in the antioxidant determinants (antioxidants/assays) in the peel and cortex region of apple cultivars, respectively. Major contributor for antioxidant activity in both apple peel and cortex was total flavonoid content. Cultivars ‘Well Spur’ and ‘Oregon Spur II’ were found to be substantially rich in these two antioxidants. The antioxidant activity was best expressed by the in vitro FRAP assay in both the fractions. Non-hierarchical K-medoids clustering reflected the presence of an antioxidant/ assay protocol apart from the antioxidant/assay we considered in this study that needs further exploration to get full spectra of antioxidant profile across apple genotypes. Based on multivariate analysis and the concept of RACI, the FRAP antioxidant assay is recommended for determining antioxidant activity in apples.