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51.
Ruchi Jain Seshagiri Raghukumar Kari Sambaiah Yasuyuki Kumon Toro Nakahara 《Marine Biology》2007,151(5):1657-1664
Thraustochytrid protists characteristically accumulate high amounts of lipids, much of which is comprised of the polyunsaturated
fatty acid, docosahexaenoic acid (DHA). Since DHA is important in human health, thraustochytrids have attracted much attention
from the point of view of biotechnology. However, the biological rationale of DHA production in the storage lipids of these
organisms is not clear. We carried out three experiments to study this. (1) The fate of lipids in thraustochytrids during
development was studied by staining lipids of vegetative cells with the fluorescent vital stain for lipids, namely Nile blue,
following the growth of the cells. The fluorescent lipid bodies decreased in abundance in freshly formed motile limaciform
amoeboid cells and subsequently disappeared when they moved away. When vegetative cells produced vast extensions of plasma
membrane, the ectoplasmic net elements (EN), the fluorescent lipids appeared to be transported to them. (2) Changes in lipids
and DHA during starvation were examined in cells with enhanced lipid and DHA contents and those in which they were not enhanced.
Cells in which lipids and DHA were enhanced by refrigerating them for 48 h survived starvation for a longer period. Compared
to cells that had not been refrigerated, total fatty acids, as well as DHA were marginally higher in pre-refrigerated cells,
while palmitic acid levels were lower. Starvation of cells resulted in a gradual decrease of absolute concentrations and percentage
levels of DHA after 8 days, while percentage of palmitic acid levels increased. (3) The relationship between DHA and specific
gravity of cells was studied by comparing cells pre-refrigerated as above with those which were not pre-refrigerated. Refrigerated
cells with increased lipids and DHA showed higher specific gravities than non-refrigerated cells. We suggest the following
roles for storage lipids and DHA in thraustochytrids: (1) lipids serve as energy sources during movement of cells and for
production of EN; (2) DHA in storage lipids become distributed in the plasma membrane when EN are formed; (3) DHA is preferably
utilized as a fatty acid energy reserve during starvation and (4) an unknown mechanism results in negative buoyancy of cells
when total lipids and DHA are marginally enhanced. DHA in storage lipids might be crucial to the survival of thraustochytrid
cells. 相似文献
52.
Dash K Saha K Pandey AK Jain AK Mukherjee A 《Journal of environmental biology / Academy of Environmental Biology, India》2003,24(3):265-269
Light microscopic and ultra-structural studies of the lymphoid tissues such as blood immunocytes, spleen and pronephros of the freshwater catfish, Clarias batrachus, were carried out. The peripheral blood showed nucleated erythrocytes, total leucocytic count (TLC) more than that observed in mammalian blood and leucocytes with morphological appearance similar to the mammalian white blood cells (WBCs). The spleen and pronephros showed presence of numerous lymphocytes, monocytes and nucleated red blood cells (RBCs) along with hemosiderin-containing macrophages. The morphology of lymphoid organs of the catfish has been discussed in light of the evolution of the immune system in this class of vertebrates. 相似文献
53.
Arun V. Someshwar Ashok K. Jain Ray C. Whittemore Larry E. LaFleur William J. Gillespie 《Chemosphere》1990,20(10-12)
The results of a study designed to quantify the levels of PCDD/Fs in boiler and control device ashes resulting from burning sludge of bleached mill origin, admixed with bark, are summarized. 相似文献
54.
Shalini-Singh Dureja P Kumar S Jain MC 《Journal of environmental science and health. Part. B》1999,34(6):965-974
Laboratory studies were undertaken to evaluate the persistence of alpha-endosulphan, beta-endosulphan and endosulphan sulphate in four diverse soils under non-flooded and flooded conditions. Significant variations were observed in the extent of persistence of the three chemicals in different non-flooded soils with maximum persistence observed in Alfisol and the least in Mollisol having near neutral pH and higher organic matter. Degradation was more in all the flooded soils than in the non-flooded counterpart but in Vertisol under flooded and non-flooded conditions, the rate of degradation of endosulphan sulphate was found to be nearly same. 相似文献
55.
In today’s world of stricter drinking water disinfection standards there is a search for disinfection solutions that abide by the new standards while keeping the disinfection operation cost-efficient and safe. Ozone disinfection has the potential not only to meet but also to exceed the limits. Along with disinfection, the use of ozone for drinking water treatment can also have many other benefits such as taste and color removal, iron and manganese removal, and insecticide removal. p]Ozone disinfection has been used widely in Europe for well over a century, but many of its great benefits are just now being realized in the United States. Ozone disinfection has been the focus of many recent studies in the drinking water field. p]The purpose of the research for this paper was to analyze ozone disinfection from technology transfer and related policy perspectives. This paper reports the aspects used to analyze the technology as well as the results. A modified version of the Strategic Technology Evaluation Program was used to evaluate ozone disinfection’s transfer viability. p]This study has demonstrated that ozone disinfection, to be fully accepted into the drinking water industry, must first be accepted by the American Water Works Association, a nationally recognized professional and trade organization. Once this acceptance is gained, individual municipalities will more readily accept the technology. p]Another driving force that will likely bring about the adoption of ozone disinfection of drinking water would be stricter drinking water disinfection standards that can be best met by this technology. 相似文献
56.
Yong-Chul Jang Pradeep Jain Thabet Tolaymat Brajesh Dubey Timothy Townsend 《Journal of environmental management》2009,90(2):320-327
Disposal and beneficial-use options for street sweeping residuals collected as part of routine roadway maintenance activities in Florida, USA, were assessed by characterizing approximately 200 samples collected from 20 municipalities. Total concentrations (mg/kg or μg/kg) and leachable concentrations (mg/L or μg/L) of 11 metals and a number of organic pollutant groups (volatile organics, semi-volatile organics, pesticides, herbicides, carbamates) in the samples were measured. The synthetic precipitation leaching procedure (SPLP) was performed to evaluate the leachability of the pollutants. From the total metal analysis, several metals (e.g., arsenic, barium, chromium, copper, nickel, lead, and zinc) were commonly found above their detection limits. Zinc was found to have the highest mean concentration of all metals measured (46.7 mg/kg), followed by copper (10.7 mg/kg) and barium (10.5 mg/kg). The metal with the smallest mean concentration was arsenic (0.48 mg/kg). A small fraction of the total arsenic, barium, lead, and zinc leached in some samples using the SPLP; leached concentrations were relatively low. A few organic compounds (e.g., 4,4′-DDT, endrin, and endosulfan II) were detected in a limited number of samples. When the total and leaching results were compared to risk-based Florida soil cleanup target levels and groundwater cleanup target levels, the street sweepings were not found to pose a significant human-health risk via direct exposure or groundwater contamination. 相似文献
57.
Jain Piyush Kumar Lanjewar Atul Rana Kunj Bihari Meena Makkhan Lal 《Environmental science and pollution research international》2021,28(4):4019-4055
Environmental Science and Pollution Research - Solar power is one of the main sources of renewable energy which helps for protecting the environmental and reducing pollution. Technologies and... 相似文献
58.
Muhammad Iftikhar Ozcan Rasim Jain Vipin Ramos-Meza Carlos Samuel Chawla Chanchal 《Environmental science and pollution research international》2023,30(5):11321-11331
Environmental Science and Pollution Research - In light of increasing concerns about climate change and energy security, renewable energy has been seen as the most promising solution to fulfil... 相似文献
59.
Rahul Jain Makkhan Lal Meena Manoj Kumar Sain Govind Sharan Dangayach 《International journal of occupational safety and ergonomics》2019,25(2):194-199
Purpose. In ergonomics and human factors investigations, pulling force (PF) estimation has usually been achieved using various types of biomechanical models, and independent approximation of PF was done with the help of upper extremity joints. Recently, multiple regression methods have gained importance for task-relevant inputs in predicting PF. Artificial neural networks (ANNs) also play a vital role in fitting the data; however, their use in work-related biomechanics and ergonomics is inadequate. Therefore, the current research aimed to accomplish comparative investigation of ANN and regression models by assessing their capacity to predict PF values. Methods. Multipositional PF data were acquired from 200 subjects at three different handle heights and body locations. ANN and regression models were formed using a random sample of three subsets (75% training, 15% selection, 10% validation) for proving the outcomes. Results. The comparison of ANN and regression models shows that the predictions of ANN models had a profoundly explained variance and lower root mean square difference values for the PF data at three handle heights. Conclusions. These outcomes advise that ANNs offer a precise and robust substitute for regression methods, and should be considered a useful method in biomechanics and ergonomics task assessments. 相似文献
60.
Ram B. Jain 《毒物与环境化学》2015,97(9):1276-1287
Data from National Health and Nutrition Examination Survey were used to evaluate the impact of pregnancy on the levels of triclosan (TCS) in urine. Regression models were fitted to evaluate this association with adjustment for other factors that may affect the levels of TCS. Pregnant females had higher levels of TCS than non-pregnant females but the differences were not statistically significant. Levels of TCS were statistically significantly lower during the second trimester than during the third trimester. Smoking was associated with statistically significantly lower levels of TCS. The reasons for the association between smoking and the levels of TCS are not known. Further research is needed in this area. 相似文献