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81.
Allelopathic effect of Ageratum conyzoides L., Cynodon dactylon (L.) Pers., Parthenium hysterophorus L., and Solanum nigrum L. were examined on seed germination, seedling growth, total protein content and protein profile on Ankur, Bhatt, Bragg, PK -416, PS-1042 and Shilajeet varieties of soybean (Glycine max (L) Merill). Aqueous extracts of weeds (10% w/v) showed both inhibitory and stimulatory influence on percent seed germination and seedling growth in different varieties of soybean. On the basis of per cent reduction in different parameters, the variety Bragg and PS-1042, and Shilajeet were resistant and susceptible respectively to different weed extracts, and among weed extracts, S. nigrum was most effective followed by P. hysterophorus compared to others. The total protein content (mg/g f wt.) in different varieties was increased with all the weed extracts except Bragg with C. dactylon and P. hysterophorus, PS-1042 with A. conyzoides and Shilajeet with C. dactylon, in which it was decreased. The protein banding pattern in different varieties not only differ between control and treatments but also among treatments. The order of susceptibility of different varieties with different weed extracts followed the order: Ankur > PK-416 > Bhatt > Shilajeet > Bragg and > PS-1042.  相似文献   
82.
Methane emissions from a coastal lagoon: Vembanad Lake,West Coast,India   总被引:6,自引:0,他引:6  
An attempt has been made to estimate methane fluxes from a tropical coastal wetland the Vembanad Lake, a lagoon along the West Coast of India. It has been found that Vembanad Lake contributes significant amount of methane to the atmosphere. Average emissions varied spatially within the lake. Methane emissions were 193.2 +/- 24.5 mg m(-2) h(-1) at Kumaragam (fresh water) as compared to 9.3 +/- 9.6 mgm(-2) h(-1) at Pullot (brackish water) site. Seasonal variation was significant between pre- and post-monsoons. Soil temperature, time of the day, salinity sediment organic carbon, all control the rate of methane emissions from the Vembanad Lake.  相似文献   
83.
84.
A simple high resolution technique for human chromosomes is described for fibroblasts obtained from amniotic fluid cell cultures. The application and clinical significance of this technique in prenatal diagnosis is discussed.  相似文献   
85.
The indiscriminate and injudicious use of pesticides particularly endosulfan in agriculture and animal husbandry practices has considerably increased the risk of human health hazard. The present work was therefore undertaken to evaluate the toxic effect of endosulfan on the vital organs viz. liver and kidney of rat. Oral administration of endosulfan at the dose level of 10 mg/kg b.wt./day for two and four weeks showed toxic interference with the biochemistry and histology of rat liver and kidney. The biochemical parameters viz. Aspartate amino transferase, alanine amino transferase, acid phosphatase, alkaline phosphatase, bilirubin urea and creatinine were increased which clearly showed the hepato and nephrotoxic effect of endosulfan. Histopathologically the size of liver was increased, sinusoidal dilation, pyknotic nuclei, cytoplasmic degranulation and various nuclear aberrations were observed. Similarly pathological alterations viz. chronic glomerulonephritis, glomerulosclerosis, odenoma and glomerulus deposits were observed in the kidney.  相似文献   
86.
The effects of sublethal concentration of fenvalerate on DNA, RNA, RNA/DNA ratio and protein contents were estimated in gill and kidney tissues of an air breathing fish, Clarias batrachus. Fenvalerate reduced the DNA content in gill, whereas it did not produce any significant effect on DNA in kidney. This tissue-specific change in DNA content may be due to differential effects of fenvalerate or its metabolite(s) on synthesis and/degradation of DNA in gill and kidney cells of the fish. RNA and protein contents declined substantially in both the tissues in response to fenvalerate treatment. However, RNA/DNA ratio remains unchanged. It indicates that decrease in protein content in response to fenvalerate treatment might have been brought about by reduce rate of translation of messenger (mRNA) without a decrease in concentration of ribosomes.  相似文献   
87.
The tropospheric sulfate radiative forcing has been calculated using an interactive chemistry scheme in LMD-GCM. To estimate the radiative forcing of sulfate aerosol on climate, a consistent interaction between atmospheric circulation and radiation computation has been allowed in LMD-GCM. The model results indicate that the change in the sulfate aerosols number concentration is negatively correlated to the indirect radiative forcing. The model simulated annual mean direct radiative forcing ranges from −0.1 to −1.2 W m−2, and indirect forcing ranges from −0.4 to −1.6 W m−2. The global annual mean direct effect estimated by the model is −0.48 W m−2, and that of indirect is −0.68 W m−2.  相似文献   
88.
A case of conjoined twins with open spina bifida prenatally diagnosed at the twenty-third week of gestation is presented. The early detection of this rare and unusual malformation was initiated by the observation of markedly elevated maternal serum alphafetoprotein values. Ultrasound evidence of a misshaped cephalic pole and the appearance of one fetal body on real-time ultrasound was strongly suggestive. Elective midtrimester termination confirmed the prenatal diagnosis and was followed by a benign postpartum course.  相似文献   
89.
Extant species of the supraordinal mammal clade Euarchonta belong to the orders Primates, Scandentia, or Dermoptera. The fossil record of euarchontans suggests that they underwent their initial radiation during the Paleocene (65–55 million years ago) in North America, Eurasia, and Africa. The time and place of origin is poorly resolved due to lack of definitive fossils of euarchontan stem taxa. We describe a fragmentary humerus and two fragmentary ulnae from the latest Cretaceous of India that bear significantly on this issue. The fossils are tentatively referred to Deccanolestes cf. hislopi due to their small size and the fact that Deccanolestes is the only eutherian dental taxon to have been recovered from the same locality. The new fossils are used to evaluate the existing behavioral hypothesis that Deccanolestes was arboreal, and the competing phylogenetic hypotheses that Deccanolestes is a stem eutherian versus a stem euarchontan. The humerus resembles those of euarchontans in possessing a laterally keeled ulnar trochlea, a distinct zona conoidea, and a spherical capitulum. These features also suggest an arboreal lifestyle. The ulnar morphology is consistent with that of the humerus in reflecting an arboreal/scansorial animal. Detailed quantitative comparisons indicate that, despite morphological correlates to euarchontan-like arboreality, the humerus of Deccanolestes is morphologically intermediate between those of Cretaceous “condylarthran” mammals and definitive Cenozoic euarchontans. Additionally, humeri attributed to adapisoriculids are morphologically intermediate between those of Deccanolestes and definitive euarchontans. If adapisoriculids are euarchontans, as recently proposed, our results suggest that Deccanolestes is more basal. The tentative identification of Deccanolestes as a basal stem euarchontan suggests that (1) Placentalia began to diversify and Euarchonta originated before the Cretaceous–Tertiary boundary and (2) the Indian subcontinent, Eurasia, and Africa are more likely places of origin for Euarchonta than is North America.  相似文献   
90.
In the presented work, the effect of crosslinker geometry on the properties of PVA is reported. The aliphatic (suberic) and aromatic (terephthalic) dicarboxylic acids are used as crosslinker molecules. On the basis of tensile test and thermal properties, it is observed that crosslinking of PVA by suberic acid is more effective than terephthalic acid. The maximum strength measured in crosslinked samples is 32.5 MPa for suberic acid crosslinked PVA which is higher than that of neat PVA (22.6 MPa). Swelling study shows that 8 h crosslinked terephthalic acid (35% w/w) samples have a minimum of 5.4% of water uptake compared to neat PVA, which dissolves readily in water. DTGA shows that the decomposition temperature of crosslinked PVA is 345?°C while neat PVA has a decomposition temperature of 315?°C. FTIR spectroscopy confirms the formation of crosslink ester bond in crosslinked PVA. The crosslinked samples kept for bio-degradation show maximum degradation in terephthalic acid (15% w/w) crosslinked PVA.  相似文献   
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