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1.
Helicteres isora root extracts were studied for antinociceptive activity on acetic acid-induced writhing test in mice, at a dose of 250 mg/kg. Petroleum ether, chloroform and aqueous ethanol extracts have shown significant activity. 相似文献
2.
Distribution,habitat associations and conservation implications of Sri Lankan freshwater terrapins outside the protected area network 下载免费PDF全文
Suranjan Karunarathna A. A. Thasun Amarasinghe Sujan Henkanaththegedara Thilina Surasinghe Majintha Madawala Dinesh Gabadage Madhava Botejue 《水产资源保护:海洋与淡水生态系统》2017,27(6):1301-1312
- Terrapins are integral to many freshwater ecosystems, yet are imperilled at a global scale. In Sri Lanka, terrapins are understudied; thus, much of their natural history and distribution status remain unknown. Such paucity of studies impedes conservation.
- In this study, 79 freshwater habitats located outside the protected area network of south‐western Sri Lanka were surveyed to document current population densities and habitat use of two terrapin species: Indian black terrapin (Melanochelys trijuga thermalis ) and flap‐shelled terrapin (Lissemys ceylonensis ). Local inhabitants were interviewed to assess human threats towards terrapins.
- Both species were recorded in low densities: 1–2 individuals ha?1. Indian black terrapin was found in half of the surveyed sites while flap‐shelled terrapin occurred in one‐third of the surveyed sites. Highly urbanized river basins had the lowest densities for both species while rural basins supported higher numbers. Basking was the predominant behaviour of both species and large woody debris and boulders were preferred as basking substrates, together with sparse‐canopy aquatic habitats with intact marshlands.
- Overharvesting for meat was a major threat for terrapins. Most local inhabitants were unaware of legislation on terrapin conservation and the ecological importance of terrapins. Human threats such as pollution, modification of aquatic and wetland habitats, and loss of riparian forests were frequently observed in surveyed sites. Terrapin populations outside the protected area are at risk as evidenced by lower population densities and a multitude of human threats.
- A landscape‐scale ecosystem‐based conservation approach is recommended for Sri Lanka's terrapins with incorporation of lands with different management regimes (privately owned, municipality managed) into the protected area network. Current environmental legislation should be revised to support buffer zone delineation for aquatic habitats, wetland restoration, and landscape‐scale connectivity.
3.
L. T. Khemani M. S. Naik G. A. Momini Krishnanand S. D. Kachre A. Mary Selvam Bh. V. Ramana Murty 《Water, air, and soil pollution》1980,13(3):303-316
Observations on gaseous and particulate pollutants were undertaken at four locations in the region of a thermal power plant (TPP), which is under construction at Tuticorin, south India. The predicted concentrations Of SO2 due to the emissions from the TPP and its possible impact on the inhabitants and climate in the downwind region were evaluated. Also, the predicted concentrations downwind of a Petrochemical Industrial Complex (PIC) located in the vicinity of the TPP were computed and compared with the measured concentrations. The predicted maximum concentration of SO2 at 6 km downwind of TPP is about 530 μg m?3 under most favourable wind conditions. The anticipated increase in SO2 due to the thermal power plant under construction may therefore be substantial. The predicted concentrations Of SO2, at a distance of 1.8 km downwind of the PIC, varied between 34 and 216 μg m?3 for wind directions ranging from 70 to 90° and for Pasquill stability category C. The plume would be over the observational site when the wind direction is 80°. The maximum measured concentration was 23 ug m?3. The discrepancy was due to the rapid fluctuations in the wind direction during the observational period over a wide range from 20 to 90°. 相似文献
4.
Precipitation chemistry at sinhagad-a hill station in India 总被引:1,自引:0,他引:1
Medha S. Naik G. A. Momin A. G. Pillai P. D. Safai P. S. P. Rao L. T. Khemani 《Water, air, and soil pollution》1995,85(4):2161-2166
The chemistry of precipitation in remote sites such as mountain tops is of interest in the study of atmospheric pollution and acid rain. The chemical composition measured at mountain site which is away from industrial and urban areas is useful as a reference level and it allows to determine the extent of anthropogenic contamination. Hence, rain water samples were collected at Sinhagad (18°21N, 73°45E, 1450 m asl during the monsoon season (June-September) of 1992 and were analysed for major ions. The precipitation samples collected at Sinhagad were alkaline in nature and pH values ranged between 5.9 to 6.76. The ionic composition was dominated by soil dust The concentration of Ca2+ was highest among all the ions. The concentrations of excess SO3
2– and NO4
– were small (23.8 and 15.2 eq l–1 respectively) compared to the values of polluted regions in India. The correlation coefficient between the ions and pH values was calculated and it was found to be maximum in case of Ca2+. Precipitation samples collected at Sinhagad were alkaline owing to higher concentration of Ca2+ and lower levels of acidic pollutants (SO4
2– and NO3
–). 相似文献
5.
L. T. Khemani G. A. Momin Medha S. Naik R. Kumar Bh. V. Ramana Murty 《Water, air, and soil pollution》1985,24(2):131-140
Surface measurements of Aitken nuclei have been made at a few representative environments in India. The periods of measurements have ranged from a few days to a few years depending upon the place of measurement. Aircraft measurements of Aitken nuclei were made at one of the locations during three successive monsoon periods. During part of the time simultaneous measurements were made of the trace gases SO2, NH3, NO2, and O3. The study presents the seasonal and diurnal variation of Aitken nuclei in the different environments and their association with the trace gas concentrations. 相似文献
6.
A.G. Pillai Medha S. Naik G.A. Momin P.S.P. Rao P.D. Safai K. Ali Henning Rodhe Lennart Granat 《Water, air, and soil pollution》2001,130(1-4):475-480
Rain water and dustfall deposition samples were collected at Pune, an urban site (1992–98) and at Sinhagad, a rural site (1992–94). The samples were collected with wet-only and bulk collectors at Pune and with bulk collector at Sinhagad. The samples were analyzed for major ions, pH and conductivity. The study showed that the rain water at both places is alkaline (pH > 5.6). The average pH at Pune was 6.1. Neutralising components, indicated by Ca and non sea salt (nss) Mg have higher concentrations than the acidifying components SO4 and NO3. The wet deposition fluxes of all the ionic components were higher than the dustfall fluxes. Relative contribution from dustfall was largest for K, Ca, Mg and NO3. Dustfall was greater at Pune, compared to Sinhagad for all components and up to double for Ca. 相似文献
7.
G.M. Bhopale S.R. Naik G.G. Bhave S.S. Naik A. Gogate 《Comparative immunology, microbiology and infectious diseases》1997,20(4):309-314
An enzyme linked immunosorbent assay (ELISA) using penicillinase was developed in the form of diagnostic kits (Toxokit-G and Toxokit-M) for the detection of IgG and IgM antibodies to Toxoplasma gondii. The performance of both the kits was compared with commercially available diagnostic kits, i.e. Enzygnost-Toxoplasmosis/IgG (Behring Co., Germany), TOXOTEK-G (Flow Lab., U.K.) and Toxoplasma IgM Microassay (Diamedix Corp., U.S.A.) by testing toxoplasma-suspected human serum samples. The results indicate a good reliability between these diagnostic kits. Toxokit-G has 86.66 and 96.05% sensitivity and specificity respectively. The main advantage of Toxokit-G is that the end result can be assessed visually without using sophisticated instruments. Toxokit-M has 100% sensitivity and specificity and test results were not affected by the presence of antitoxoplasma IgG antibodies, rheumatoid factor or antinuclear antibodies. 相似文献
8.
The physical properties of fruit are important in designing and fabricating equipment and structures for handling, transporting, processing and storage, and also for assessing quality. The study was conducted to investigate some physical properties of jatropha fruit at various moisture levels. The average length, width, thickness and 1000 mass were 29.31 mm, 22.18 mm, 21.36 mm and 1522.10 g, respectively, at moisture content of 7.97% d.b. The geometric mean diameter increased from 24.03 to 24.70 mm and the sphericity varied between 0.82 and 0.83 as moisture content increased from 7.97% to 23.33% d.b., respectively. In the same moisture range, the bulk and true densities decreased from 278 to 253 and 546 to 435 kg m?3, respectively, whereas the corresponding porosity also decreased from 49.08% to 41.84%. As the moisture content increased from 7.97% to 23.33% d.b., crushing strength was decreased from 275 to 79 N, whereas the angle of repose and surface areas were found to increase from 36.41° to 41.72° and 1815.73 to 1917.59 mm2, respectively. The static coefficient of friction of jatropha fruit increased linearly against the surfaces of three structural materials, namely plywood (47.81%), mild steel (62.88%) and aluminium (34.82%) as the moisture content increased from 7.97% to 23.33% d.b. 相似文献
9.
The study was conducted to investigate some moisture-dependent physical properties of jatropha seed namely, seed dimension, 1000 seed mass, surface area, sphericity, bulk density, true density, angle of repose and static coefficient of friction against different materials. The physical properties of jatropha seed were evaluated as a function of moisture content in the range of 4.75–19.57% d.w. The average length, width, thickness and 1000 seed mass were 18.65 mm, 11.34 mm, 8.91 mm and 741.1 g, respectively at moisture content of 4.75% d.w. The geometric mean diameter and sphericity increased from 12.32 to 12.89 mm and 0.66 to 0.67 as moisture content increased from 4.75 to 19.57% d.w., respectively. In the same moisture range, densities of the rewetted jatropha seed decreased from 492 to 419 kg m−3, true density increased from 679 to 767 kg m−3, and the corresponding porosity increased from 27.54 to 45.37%. As the moisture content increased from 4.75 to 19.57% d.w., the angle of repose and surface area were found to increase from 28.15° to 39.95° and 476.78 to 521.99 mm2, respectively. The static coefficient of friction of jatropha seed increased linearly against the surfaces of three structural materials, namely plywood (44.12%), mild steel sheet (64.15%) and aluminum (68.63%) as the moisture content increased from 4.75 to 19.57% d.w. 相似文献
10.
Chromosome pairing within genomes in maize-Tripsacum hybrids 总被引:1,自引:0,他引:1
When the ten chromosomes of maize were inserted inlto a polyploid (2n = 72) Tripsacum dactyloides background they formed up to five pairs at meiosis. Two plants that each contained 36 Tripsacum and 14 maize chromosomes were deprived from the F(1) of maize x Tripsacum. Chromo. somes of these plants frequently formed 25 bivalents, 18 between Tripsacum chromosomes and seven between maize chromosomes. Maize chromosomes could be distinguished from Tripsacum chromosomes on the basis of size. The withint-genome pairing is probably induced by the genetic background. 相似文献