North Eastern Hill University

About: North Eastern Hill University is a education organization based out in Shillong, Meghalaya, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 2318 authors who have published 4476 publications receiving 48894 citations.

Brownian rectifiers in the presence of temporally asymmetric unbiased forces.

Abstract: The efficiency of energy transduction in a temporally asymmetric rocked ratchet is studied. Time asymmetry favors current in one direction and suppresses it in the opposite direction due to which large efficiency $\ensuremath{\sim}50%$ is readily obtained. The spatial asymmetry in the potential together with system inhomogeneity may help in further enhancing the efficiency. Fine tuning of system parameters considered leads to multiple current reversals even in the adiabatic regime.

On Construction of Robust Composite Indices by Linear Aggregation

Abstract: In this paper we construct thirteen different types of composite indices by linear combination of indicator variables (with and without outliers/data corruption). Weights of different indicator variables are obtained by maximization of the sum of squared (and, alternatively, absolute) correlation coefficients of the composite indices with the constituent indicator variables. Seven different types of correlation are used: Karl Pearson, Spearman, Signum, Bradley, Shevlyakov, Campbell and modified Campbell. Composite indices have also been constructed by maximization of the minimal correlation. We find that performance of indices based on robust measures of correlation such as modified Campbell and Spearman, as well as that of the maxi-min based method, is excellent. Using these methods we obtain composite indices that are autochthonously sensitive and allochthonously robust. This paper also justifies simple mean-based composite indices, often used in construction of human development index.

Effect of Eupatorium adenophorum Spreng leaf extracts on the mustard aphid, Lipaphis erysimi Kalt: a scanning electron microscope study.

Abstract: Scanning electron microscopic study revealed some remarkable adverse effects of Eupatorium adenophorum Spreng leaf extract on cuticular and antennal sensilla of the mustard aphid, Lipaphis erysimi Kalt. The study appears to be the first of its kind in providing evidence on toxic property of the plant on certain agricultural pests, although the indigenous tribes of the region know the insecticidal property of the plant for a long time. The study further provides indications regarding the neurotoxic nature of the leaf extract since it has caused abnormalities in the sensory structures. The presence of prominent swellings in some sensilla and shrinkage in others suggests that the leaf extract affects different systems through different mechanisms. The possible use of the plant as a potential biopesticide against certain insect pests is discussed.

Therapeutic efficacy of Zanthoxylum rhetsa DC extract against experimental Hymenolepis diminuta (Cestoda) infections in rats.

Abstract: Zanthoxylum rhetsa DC (Rutaceae), commonly called prickly ash, is used in the folk medicine of Naga tribes in India as a deworming remedy. In the present study, the therapeutic efficacy of Z. rhetsa leaf extract was investigated against experimental Hymenolepis diminuta (Cestoda) infections in albino rats. The efficacy of extract was determined on the basis of reduction in the eggs per gram of feces (EPG) counts and worm load following treatment with 100, 200, 400 and 800 mg/kg, p.o. doses of plant extract. For comparison’s sake, animals were also treated with a reference drug, praziquantel at 5 and 25 mg/kg body weight doses. Three treatment regimes were followed to monitor the effects of extract on cestode parasite: (1) Treatment on day 2–4 postinoculation (pi) of cysticercoids against the larval stages; (2) treatment on day 8–10 pi against the immature stages; and (3) treatment on day 21–25 pi against the adult stages of parasite. The extract revealed its maximum efficacy against the larval stage, where its 800 mg/kg dose showed a worm count reduction of 86.60%, compared to 80.00% by the reference drug, praziquantel (5 mg/kg dose). The EPG counts also decreased drastically from 23,389 ± 2,372 to 0 in the same treatment group, compared to 33,161 ± 1,383 recorded in the control group. The efficacy of extract was found to be of moderate level against the immature and adult stages of parasite. The present investigation holds the evidence that the leaves of Z. rhetsa possess significant anticestodal property and supports its use in folk medicine.