Acquiring Vitellogenic Competence in the Rice Pest Nilaparvata lugens Stal: Effects of a Juvenile Hormone Analogue, Hydroprene

Pradeep A. R.,Nair V. S. K. Korean Society of Sericultural Science 2005 International Journal of Industrial Entomology Vol.10 No.2

Though many insecticides are commercially available, development of resistance, pest resurgence and effects on non-target organisms led to the search for alternate insect pest management (IPM) strategy based on larval growth and reproductive fitness. Reproductive potential of insects depends on its acquiring of vitellogenic competence which is under hormonal control. Exogenous application of analogues of JR (JHAs) and ecdysterone could derail normal development and reproduction in insects by manipulating an array of physiological processes. In the rice pest, brown planthopper, Nilaparvata lugens, JHA, hydroprene induced metathetely from the fifth (final) instar nymphs in an age-dependent manner. Day 0 of the final instar showed highest sensitivity to induce this abnormal development. Adults emerged from treated day 3 nymphs looked normal. Both the morphotypes were reproductively incompetent and showed partial to complete sterility. Pre-adult exposure of the ovarian tissue to hydroprene suppressed mitotic division of germinal cells and induced abnormalities in the later s1ages of growth and differentiation of ovary in N. lugens. More over the nymphal exposure to hydroprene inhibited patency changes of follicular epithelium and affected competence of the follicles for yolk sequestration. In the absence of ovarian growth and oocyte differentiation, germarium found disintegrated, trophic core regressed and terminal oocytes resorbed. Hydroprene exposure to newly ecdysed brachypterous females did not affect ovarian development and egg production. Proper larval-adult transition appeared as a. prerequisite for vitellogenic competence in N. lugens for which the ovarian tissues must be exposed to ecdysterone in the internal milieu devoid of JH.

Chemopreventive Potential of an Ethyl Acetate Fraction from Curcuma Longa is Associated with Upregulation of p57^kip2 and Rad9 in the PC-3M Prostate Cancer Cell Line

Rao, K.V.K.,Samikkannu, T.,Dakshayani, K.B.,Zhang, X.,Sathaye, S.S.,Indap, M.A.,Nair, Madhavan P.N. Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.3

Background: Turmeric ($Curcuma$ $longa$) has been shown to possess anti-inflammatory, antioxidant and antitumor properties. However, despite the progress in research with $C.$ $longa$, there is still a big lacuna in the information on the active principles and their molecular targets. More particularly very little is known about the role of cell cycle genes $p57^{kip2}$ and Rad9 during chemoprevention by turmeric and its derivatives especially in prostate cancer cell lines. Methods: Accordingly, in this study, we have examined the antitumor effect of several extracts of $C.$ $longa$ rhizomes by successive fractionation in clonogenic assays using highly metastatic PC-3M prostate cancer cell line. Results: A mixture of isopropyl alcohol: acetone: water: chloroform: and methanol extract of $C.$ $longa$ showed significant bioactivity. Further partition of this extract showed that bioactivity resides in the dichloromethane soluble fraction. Column chromatography of this fraction showed presence of biological activity only in ethyl acetate eluted fraction. HPLC, UV-Vis and Mass spectra studies showed presence three curcuminoids in this fraction besides few unidentified components. Conclusions: From these observations it was concluded that the ethyl acetate fraction showed not only inhibition of colony forming ability of PC-3M cells but also up-regulated cell cycle genes $p57^{kip2}$ and Rad9 and further reduced the migration and invasive ability of prostate cancer cells.

Bioprocess Optimization - a Challenge

( Tapobrata Panda ),( P S R Babu ),( J A Kumari ),( D S Rao ),( K Theodore ),( K Jagannandha Rao ),( S Siva Kesava ),( A Kapat ),( S R Nair ),( J Sinha ),( R Sreenivas ),( G Lakshmi Prasanna ),( V Ven 한국미생물생명공학회 1997 Journal of microbiology and biotechnology Vol.7 No.6

Genetic variability within and among three ecoraces of the tasar silkworm Antheraea mylitta Drury, as revealed by molecular markers

K. Vijayan,C. V. Nair,P. K. Kar,T. P. Mohandas,B. Saratchandra,S. Raje Urs 한국잠사학회 2005 International Journal of Industrial Entomology Vol.10 No.1

Genetic diversity within and between populations of Antheraea mylitta Drury was studied using thirty individuals from three ecoraces using 12 ISSR and 10 RAPD primers. Raily, Daba and Modal ecoraces were collected from Chattisgarh, Jharkhand and Orissa states of India respectively. The ISSR and RAPD primers generated 94.7% and 95.6% polymorphism among the 30 individuals. The cluster analysis grouped these individuals according to their ecorace. The intra-ecoracial heterozygosity estimated with ISSR markers were 0.123 ± 0.18, 0.169 ± 0.17 and 0.214 ± 0.17 respectively for Modal, Raily and Daba ecoraces. Like wise, with RAPD markers the intraecoracial heterozygosity was 0.17 ± 0.22 in Modal, 0.229 ± 0.17 in Raily and 0.23 ± 0.19 in Daba ecoraces.However, the significantly low genetic differentiation (GST) (0.182 for ISSR and 0.161 for RAPD) and the high gene flow (Nm) (2.249 for ISSR and 2.60 for RAPD markers) among the ecoraces revealed that the amount of genetic diversity present among the ecoraces is not significant enough to make drastic genetic drifts among these ecoraces in the near future.

Improvement in the Commercial Traits of Silkworm, Bombyx mori L. by Administration of a Juvenoid, R394

Nair, K.Sashindran,Vijayan, V.A,,Trivedy, Kanika,Nair, Jula S. Korean Society of Sericultural Science 2001 International Journal of Industrial Entomology Vol.3 No.2

A synthetic juvenoid, R394 (Ethyl 9-cyclohexyl-3, 7-dimethyl-2, 4-nonadienoate) which is known to be a strong pest control agent was administered to silkworm, Bombyx mori L. in minute quantity for improving the silk yield. Based on the result of an earlier preliminary screening, three concentrations of the compound, viz., 0.1563, 0.3125, 31.25 nl/ml were prepared in the form of an emulsion and administered topically as a single dose, to separate batches of $5^{th}$ instar silkworm at 24, 48, 72 and 96 hrs to determine the required concentration and critical time of application for an economically favourable response. Two popular commercial silkworm hybrids, PM ${\times}$ NB4D2 (multivoltine${\times}$bivoltine) and KA${\times}$NB4D2 (bivoltine$\times$bivoltine) were subjected to the experiment. The medium and absolute control were maintained in parallel to compare the results. The results showed that 0.3125 nl/ml was the best concentration of the compound and 72 hrs of $5^{th}$instar was the most favourable age for its administration to get the maximum improvement in the commercial traits. The possible role of exogenous juvenoids in eliciting favourable response in silkworm which ultimately leads to improvement in the commercial traits is discussed.

Growth and Nutrient Utilization in Buffalo Calves Fed Ammoniated Wheat Straw Supplemented with Sodium Sulphate

Nair, P.V.,Verma, A.K.,Dass, R.S.,Mehra, U.R. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.3

Ten male buffalo calves (aged 6-8 months, average body wt. $88.5{\pm}0.5kg$) were divided into two groups of five animals in each. All the animals were fed on urea-ammoniated wheat straw (4% urea, 50% moisture) along with concentrate mixture (50:50 on DM basis). In addition animals in group II were given sodium sulphate to see the effect of sulphur on the utilization of nitrogen added through urea-ammoniation. This feeding practice continued for a period of 120 d, during which fortnightly body weights were taken to assess their growth rate. A metabolism trial was conducted after 90 days of feeding to know the digestibility of nutrients and their balance. Results revealed no significant difference in the intake of DM and other nutrients in two groups. The digestibility of DM, OM, EE, NDF, ADF and cellulose was alike in animals fed ammoniated straw and ammoniated straw+sodium sulphate supplemented group, whereas the digestibilities of CP and hemicellulose was significantly (p<0.01) more in group I and II respectively. There was no significant difference in intake of nitrogen, calcium and phosphorus in 2 groups. Similarly, the balance of these 3 nutrients was positive and statistically alike in two groups. Intake and excretion of sulphur through faeces and urine was significantly (p<0.01) more in group II than in group I. Inspite of higher excretion of sulphur through faeces and urine in group II, the sulphur balance was significantly (p<0.05) more in group II than in group I, probably due to significantly (p<0.01) higher intake of sulphur in this group. There was no significant difference in total body weight gain or average daily gain between two groups, indicating that addition of sodium sulphate did not have any positive effect on these parameters. Similarly the intake of DM, DCP and TDN were also alike in two groups. The DCP and TDN values of the two diets were 8.0, 60.4 and 6.8, 56.6% respectively. Feeding cost/unit gain was alike in both the groups.

Improvement in the Commercial Traits of Silkworm, Bombyx mori L. by Administration of a Juvenoid, R394

( K. Sashindran Nair ),( V. A. Vijayan ),( Kanika Trivedy ),( Jula S. Nair ) 한국잠사학회 2001 International Journal of Industrial Entomology Vol.3 No.2

A synthetic juvenoid, R394 (Ethyl 9-cyclohexyl-3, 7-dimethyl-2, 4-nonadienoate) which is known to be a strong pest control agent was administered to silkworm, Bombyx mori L. in minute quantity for improving the silk yield. Based on the result of an earlier preliminary screening, three concentrations of the compound, viz., 0.1563, 0.3125, 31.25 nl/ml were prepared in the form of an emulsion and administered topically as a single dose, to separate batches of 5th instar silkworm at 24, 48, 72 and 96 hrs to determine the required concentration and critical time of application for an economically favourable response. Two popular commercial silkworm hybrids, PM×NB4D2 (multivoltine×bivoltine) and KA×NB4D2 (bivoltine×bivoltine) were subjected to the experiment. The medium and absolute control were maintained in parallel to compare the results. The results showed that 0.3125 nl/ml was the best concentration of the compound and 72 hrs of 5th instar was the most favourable age for its administration to get the maximum improvement in the commercial traits. The possible role of exogenous juvenoids in eliciting favourable response in silkworm which ultimately leads to improvement in the commercial traits is discussed.

Water impact of three dimensional wedges using CFD

Nair, Vinod V.,Bhattacharyya, S.K. Techno-Press 2018 Ocean systems engineering Vol.8 No.2

In this paper the results of CFD simulations, that were carried out to study the impact pressures acting on a symmetric wedge during water entry under the influence of gravity, are presented. The simulations were done using a solver implementing finite volume discretization and using the VOF scheme to keep track of the free surface during water entry. The parameters such as pressure on impact, displacement, velocity, acceleration and net hydrodynamic forces, etc., which govern the water entry process are monitored during the initial stage of water entry. In addition, the results of the complete water entry process of wedges covering the initial stage where the impact pressure reaches its maximum as well as the late stage that covers the rebound process of the buoyant wedge are presented. The study was conducted for a few touchdown velocities to understand its influence on the water entry phenomenon. The simulation results are compared with the experimental measurements available in the literature with good accuracy. The various computational parameters (e.g., mesh size, time step, solver, etc.) that are necessary for accurate prediction of impact pressures, as well as the entry-exit trajectory, are discussed.

Genetic Variability Within and Among Three Ecoraces of the Tasar Silkworm Antheraea mylitta Drury, as Revealed by ISSR and RAPD Markers

( K. Vijayan ),( C. V. Nair ),( P. K. Kar ),( T. P. Mohandas ),( B. Saratchandra ),( S. Raje Urs ) 한국잠사학회 2005 International Journal of Industrial Entomology Vol.10 No.1

Growth and Nutrient Utilization in Buffalo Calves Fed Urea-ammoniated Wheat Straw and Hydrochloric Acid plus Urea Treated Wheat Straw

Nair, P.V.,Verma, A.K.,Dass, R.S.,Mehra, U.R. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.5

Ten growing male buffalo calves (aged 6-8 months, average body weight $88.2{\pm}0.57$ kg were divided randomly into two groups. Animals in group I were fed on concentrate mixture A (CP 20.2%, TDN 77.4%) and urea- ammoniated wheat straw (UAWS) while the animals in group II were fed on concentrate mixture B (CP 17.9%, TDN 77.6%) and HCl plus urea treated wheat straw (HCl UAWS) to meet their nutrient requirement for 500 g gain/d as per Kearl (1982). This feeding practice lasted for 120 days, during which fortnightly body weight were recorded to assess their growth rate. A metabolism trial was conducted after 90 days of experimental feeding to compare the digestibility of nutrients, their balance, plane of nutrition and relative cost of feeding in two groups of animals. Results revealed a significant increase in the CP content of ammoniated wheat straw due to addition of HCl viz 12.1% from 7.5%. There was a decrease in the intake of DM (p<0.05), OM (p<0.05), EE (p<0.05), NDF (p<0.01), ADF (p<0.01), cellulose (p<0.01) and hemicellulose (p<0.01) in group II as compared to group I. The digestibility (%) of DM, OM and CP was significantly (p<0.01) more in group II, whereas the digestibility (%) was significantly more for NDF (p<0.05) and hemicellulose (p<0.01) in group I than group II. There was no significant difference in the N, Ca and P balance in two groups. Intake of total DM (g/d) or (g/kg $W^{0.75}$) was significantly (p<0.01) more in group I as compared to group II, whereas the intake of DCP and TDN (g/d or g/kg $W^{0.75}$) was alike in two groups. The total body weight gain (kg), average daily gain (g/d) and feed conversion efficiency were significantly (p<0.01) more in UAWS fed group as compared to HCl UAWS fed group. Feeding cost (Rs./kg. weight gain) was significantly (p<0.05) more in group II as compared to group I. It is concluded that HCl UAWS is not suitable for the feeding of growing buffalo calves as it reduced the growth rate in comparison to UAWS fed buffalo calves.