143 research outputs found
Patterns of emergence, import of egg energy and energy export via emerging dragonfly populations in a tropical pond
No full textThe most abundant dragonflies Brachythemis contaminata, Orthetrum sabina, Diplacodes trivialis, Pantala flavescens and Trithemis festiva in the tropical pond Idumban emerged from November to April during the years 1973,1974 and 1975. The date of initiation of emergence of all the species was synchronized and tied to the events following the north west monsoon in November. During the seasons '73-74 and '74-75, as many as 10,693 and 7,910 adults emerged; females outnumbered the males in all the 5 species; male populations of B. contaminata, O. sabina, D. trivialis, P. flavescens and T. festiva represented 47, 48, 46, 49 and 44% during the '73-74 season, 48, 48, 46, 46 and 49% during the '74-75 season, respectively. The adult dragonflies equivalent to 2,442 Kcal emerged from the Pond during the season '73'-74. Of this, B. contaminata contributed 30%, D. trivialis 7%, O. sabina 12%, P. flavescens 23% and T. festiva 28%. For the season '74-75, the dragonflies equivalent to 1,602 Kcal emerged from the Pond and the contribution was in the following order: B. contaminata: 31%, O. sabina: 8%, D. trivialis: 13%, P. flavescens: 27% and T. festiva: 21%. Import of energy due to inoculation of B. contaminata eggs into the Pond Idumban was 73 Kcal/ year and the output from the Pond via emerging B. contaminata population alone amounted to 620 Kcal/ year; the net energy loss from the Pond was 548 Kcal/ year. During either season, as much as 99.7% of B. contaminata eggs failed to attain adulthood due to infertility (5.8%), unhatchability (12%) and predation during the egg and nymphal stages (82.5%). During the study, the GPP of the Pond was 26,073 Kcal/m2/ year, and output of energy through emergence of 5 dragonfly species amounted to 0.0045 Kcal/m2/year, i.e. 0.00002% of the GPP is lost through the emerging carnivorous odonates; comparable values available for the emerging detritivorous chironomids, herbivorous dipterans and mayflies fall between 1.0 and 0.1%
Structural and electrical characterization of tamarind seed polysaccharide (TSP) doped with NH4HCO2
No full textEnhanced biocompatibility of multi-walled carbon nanotubes by surface modification: Future perspectives for drug delivery system
No full textPolyethyleneglycol/silver functionalized reduced graphene oxide aerogel for environmental application
No full textConformational, vibrational spectroscopic and nonlinear optical activity studies on N,N-Di-Boc-2-amino pyridine : A DFT approach
No full textStructural, vibrational spectroscopic and quantum chemical studies on indole-3-carboxaldehyde
No full textUse of faecal weight as an indicator of food consumption in some lepidopterans
No full textCorrelation coefficients obtained between food consumed and feces defecated are highly significant in the larva of Achaea junta and other lepidopteran larvae tested. Different factors like species, stage of life, temperature, and food quality do not significantly affect the value of the correlation coefficient in the larvae tested. The reference value (i.e. the ratio between dry food consumed and dry feces weight) of 1.5 for the moths and 1.9 for the butterflies is suggested for use in the estimation of total food consumption in phytophagous lepidopterans, and its applicbility is discussed. In all tested cases, the correlation coefficients between food consumed and number of pellets defecated showed no significance, indicating the unreliablity of fecal count as an index of food consumption
Electroporatic transfer, stable integration, expression and transmission of pZpbetaypGH and pZpbetartGH in Indian catfish, Heteropneustes fossilis (Bloch)
No full textTwo recombinant transformation vectors ZpbetaypGHcDNA (6.5 kb) and ZpbetartGHcDNA (4.9 kb) were constructed with Zp promoter at their respective 5' ends and a beta-reporter gene at their 3' ends. Freshly fertilized eggs of the Indian catfish, Heteropneustes fossilis (Bloch), were electroporated at optimum conditions (0.100 kV voltage; 100 microfarad capacitance; infinity ohms resistance and 2 pulses) in the presence of one of these transformation vectors (100 microgram circular DNA mL(-1)). Survival of the electroporated embryos averaged 56% at hatching against 70% in the control eggs. Southern and expression analyses confirmed the integration and translation of the transgene in all the developmental stages tested; a random Southern analysis confirmed the persistence of the transgene up to 12 months of age in both transformants. Stable expression of the transgene in the adult transformant (G(0)) was confirmed from 30% to 60% increase in the growth of the presumptive transgenics (compared with control) and a two- to sixfold increase in beta-galactosidase (beta-gal) activity. From ZpbetaypGH (G(0)) transformants, 5 out of 10 F(1) progeny inherited the transgene into the genome of the host. Genomic DNA extracts from tailfins of F(1) ZpbetartGH transformants were subjected to Southern analysis seven successive times after digestion with different restriction endonucleases. Consistent evidence for the genomic integration of the transgene was obtained (from 12 out of 12 F(1) positive rtGH transformants) confirming stable integration. Evidence is also given for integration at multiple but identical sites of the host genome. Expression of the transgene in terms of beta-gal activity also affirmed stable integration in F(1) progenies
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