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61.
Abstract

Fusarubin analogues of Fusarium oxysporum f. sp. ciceris were investigated for antifungal activity in vitro against five soil borne phytopathogenic fungi. 3-O-Methyl-8-O-methyl-fusarubin was inhibitory towards S. sclerotiorum (EC50 0.33?mmol L?1) and Sclerotium rolfsii (EC50 0.38?mmol L?1). A structure–antifungal activity relationship of fusarubin analogues was established from their activity performance. Possible mechanism of action of these compounds was studied using molecular docking and simulations against three target enzymes which revealed receptor ligand binding affinity. Docking of 3-O-methyl-8-O-methyl-fusarubin into the succinate dehydrogenase site revealed formation of salt bridge, hydrogen bond, π–anion, π–alkyl, and Van der Waals interactions.  相似文献   
62.
The ability of young coral reef fishes to feed using solely ultraviolet-A (UV-A) radiation during ontogeny was examined using natural prey in experimental tanks. Larvae and juveniles of three coral reef fish species (Pomacentrus amboinensis, Premnas biaculeatus and Apogon compressus) are able to feed successfully using UV-A radiation alone during the later half of the pelagic larval phase. The minimum UV radiation intensities required for larval feeding occur in the field down to depths of 90–130 m in oceanic waters and 15–20 m in turbid inshore waters. There was no abrupt change in UV sensitivity after settlement, indicating that UV photosensitivity may continue to play a significant role in benthic juveniles on coral reefs. Tests of UV sensitivity in the field using light traps indicate that larval and juvenile stages of 16 coral reef fish families are able to detect and respond photopositively to UV wavelengths. These include representatives from families that are unlikely to possess UV sensitivity as adults due to the UV transmission characteristics of the ocular media. Functional UV sensitivity may be more widespread in young coral reef fishes than in the adults, and may play a significant role in detecting zooplanktonic prey.  相似文献   
63.
Pseudomonas (PI2) capable of degrading pyridine was isolated from the mixed population of the activated sludge unit which was being used for treating complex effluents, the strain was characterized. Aerobic degradation of pyridine was studied with the isolated strain and the growth parameters were evaluated. Pyridine degradation was further conformed by chromatography (HPLC) analysis. The process parameters like biomass growth and dissolved oxygen consumption were monitored during pyridine degradation. In order to conform with the plasmid capability to degrade pyridine, the requisite plasmid was isolated and transferred to DH 5alpha Escherichia coli. The subsequent biodegradation studies revealed the ability of the transformed plasmid capability to degrade the pyridine.  相似文献   
64.
This is the first report of a prenatally diagnosed case of Neu Laxova syndrome (NLS) from India. This also includes a case of NLS in monochorionic diamniotic twins and two more cases in which we were able to detect most of the features of NLS as early as 19 to 20 weeks by routine antenatal ultrasonography. Severe intrauterine growth retardation (IUGR), microcephaly, central nervous system (CNS) abnormality, joint contractures, and abnormal facies are the major diagnostic features observed in prenatal ultrasonography. Risk factors such as consanguinity and history of intrauterine death or stillbirth in siblings have been noted in all the cases, but none of the three families that were reported had previously had an affected fetus. The spectrum of skin manifestations and frequency of occurrence of major clinical features of the syndrome have been discussed. Review of the literature on NLS and possibility of detecting the syndrome in the second trimester is discussed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
65.
Environmental Science and Pollution Research - Ciprofloxacin (CIP), a widely used antibiotic, is frequently detected in the environment due to insufficient wastewater and water treatment. Hence,...  相似文献   
66.
The separation of the base flow component from a varying streamflow hydrograph is called “hydrograph analysis.” In this study, two digital filter based separation modules, the BFLOW and Eckhardt filters, were incorporated into the Web based Hydrograph Analysis Tool (WHAT) system. A statistical component was also developed to provide fundamental information for flow frequency analysis and time series analysis. The Web Geographic Information System (GIS) version of the WHAT system accesses and uses U.S. Geological Survey (USGS) daily streamflow data from the USGS web server. The results from the Eckhardt filter method were compared with the results from the BFLOW filter method that was previously validated, since measured base flow data were not available for this study. Following validation, the two digital filter methods in the WHAT system were run for 50 Indiana gaging stations. The Nash‐Sutcliffe coefficient values comparing the results of the two digital filter methods were over 0.91 for all 50 gaging stations, suggesting the filtered base flow using the Eckhardt filter method will typically match measured base flow. Manual separation of base flow from streamflow can lead to inconsistency in the results, while the WHAT system provides consistent results in less than a minute. Although base flow separation algorithms in the WHAT system cannot consider reservoir release and snowmelt that can affect stream hydrographs, the Web based WHAT system provides an efficient tool for hydrologic model calibration and validation. The base flow information from the WHAT system can also play an important role for sustainable ground water and surface water exploitation, including irrigation and industrial uses, and estimation of pollutant loading from both base flow and direct runoff. Thus, best management practices can be appropriately applied to reduce and intercept pollutant leaching if base flow contributes significant amounts of pollutants to the stream. This Web GIS based system also demonstrates how remote, distributed resources can be shared through the Internet using Web programming.  相似文献   
67.
Airborne particles in fugitive emissions have been measured at a slagging fixed-bed coal-gasification pilot plant using lignite. Sampling was conducted during shutdown operations and opening of the gasifier following an aborted startup. Aerosol collected with a Sierra high-volume impactor was subjected to analysis by gas chromatography, mass spectrometry, and scanning electron microscopy; aerosol collected with an Andersen low-volume impactor was subjected to flameless atomic absorption analysis. The data show that the bulk of the trace organic material is associated with small particles: these data are similar to data on ambient air reported in the literature. Particle morphologies resemble those of fly ash from coal combustion, including smooth spheres, vesicular spheres, and crystalline material. Trace element size distributions are bimodal and resemble data for ambient air. Pb-containing particles are generally submicron, while particles containing Al, Fe, and other crustal species are mostly of supermicron size. Aluminum-based aerosol enrichment factors calculated from the lignite composition show that the composition of the aerosol resembles that of the coal, with the exception of modest enrichments of Mg, Na, As, and Pb in the submicron size range. Aerosol enrichment factors based on the earth's crustal composition are somewhat greater than those based on coal composition for several elements, suggesting potential errors in using crustal enrichment data to investigate chemical fractionation during aerosol formation.  相似文献   
68.
Comparative toxicological studies of textile dye wastewater (untreated and treated) on a freshwater fish, Gambusia affinis, revealed a marked reduction in mortality and cytotoxic effects on RBCs, measured as reduction in their counts and percent changes in their shape (poikilocytosis) and variation in their size (anisocytosis)}, after subjecting them to both physicochemical and biological treatments. On comparing the data of mortality and the cytotoxic effects on RBCs, we found poikilocytosis is a better indicator for toxicity measurement of both untreated as well as treated wastewater, especially at their lowest concentrations where percent mortality was found to be either nil or lowerer than the percentage of poikilocytic RBCs. Although percent reduction in RBC counts and changes in their size (anisocytosis) indicated toxic effects of wastewaters, but EC5o values for RBC counts were usually higher than those for poikilocytosis and mortality, and non-calculable for anisocytosis suggesting their lesser sensitivity to pollutants. In view of these findings, we recommend monitoring of toxic effects of wastewaters during fish bioassay on both mortality and variation in RBC shape.  相似文献   
69.
The concentrations of polybrominated diphenyl ethers (PBDEs) 17, 28, 47, 49, 66, 85, 99, 100, 153, 154, and 183 were determined in ringed seal blubber from central East Greenland collected in 1986, 1994, 1999 and during the period 2001 to 2004. The trend of PBDEs was compared with the trends of polychlorinated biphenyls (PCBs) 28, 31, 52, 101, 105, 118, 138, 153, 156, and 180 during the same period. The levels of sigmaPBDE in East Greenland ringed seals ranged from 21.8 ng g(-1) lipid weight (1w) in 1986 to 39.3 ng g(-1) lw in 2001 and are among the highest observed in ringed seal from the Arctic. The dominating congeners were BDE-47 (75.4%) and BDE-99 (9.7%). The concentrations of PBDEs and PCBs increased with the age of the seals, and therefore only young seals < or =4 years old) were included in the temporal trend analyses. No significant trend (p > 0.14) was observed in sigmaPBDE or the congeners BDE 28, 47 and, 99 during the period while sigmaPCB decreased significantly (p = 0.004) over the period from 1986 to 2004 with an estimated annual rate of 4.3%.  相似文献   
70.
The mass transfer of naphthalene vapor to water droplets in air was studied in the presence of ozone (O3) in the gas phase. A falling droplet reactor with water droplets of diameters 55, 91, and 182 microm was used for the study. O3 reacted with naphthalene at the air-water interface, thereby decreasing the mass transfer resistance and increasing the rate of uptake of naphthalene into the droplet. A Langmuir-Hinshelwood reaction mechanism at the air-water interface satisfactorily described the surface reaction. The first-order surface reaction rate constant, ks, increased with decreasing droplet size. Three organic intermediates were identified in the aqueous phase as a result of ozonation of naphthalene at the surface of the droplet indicating both peroxidic and nonperoxidic routes for ozonation. The presence of an organic carbon surrogate (fulvic acid) increased both the partition constant of naphthalene and the surface reaction rate of O3. The heterogeneous oxidation of naphthalene by O3 on the droplet was 15 times faster than the homogeneous oxidation by O3 in the bulk air phase, whereas it was only 0.08 times the homogeneous gas-phase oxidation by hydroxyl radicals under atmospheric conditions.  相似文献   
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