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31.
Environmental Chemistry Letters - Water contamination by emerging contaminants is increasing in the context of rising urbanization, industrialization, and agriculture production. Emerging...  相似文献   
32.
Climate change vulnerability depends upon various factors and differs between places, sectors and communities. People in developing countries whose subsistence livelihood depends mainly upon agriculture and livestock production are identified as particularly vulnerable. Nepal, where the majority of people are in a mixed agro-livestock system, is identified as the world’s fourth most vulnerable country to climate change. However, there is limited knowledge on how vulnerable mixed agro-livestock smallholders are and how their vulnerability differs across different ecological regions in Nepal. This study aims to test two vulnerability assessment indices, livelihood vulnerability index and IPCC vulnerability index, around the Gandaki River Basin of central Nepal. A total of 543 households practicing mixed agro-livestock were surveyed from three districts, namely Dhading, Syangja and Kapilvastu representing three major ecological zones: mountain, mid-hill and Terai (lowland). Data on socio-demographics, livelihood determinants, social networks, health, food and water security, natural disasters and climate variability were collected and combined into the indices. Both indices differed for mixed agro-livestock smallholders across the three districts, with Dhading scoring as the most vulnerable and Syangja the least. Substantial variation across the districts was observed in components, sub-components and three dimensions (exposure, sensitivity and adaptive capacity) of vulnerability. The findings help in designing site-specific intervention strategies to reduce vulnerability of mixed agro-livestock smallholders to climate change.  相似文献   
33.
Environmental Science and Pollution Research - Research on phase change material (PCM) for thermal energy storage is playing a significant role in energy management industry. However, some hurdles...  相似文献   
34.
Environmental Science and Pollution Research - Increasing petroleum consumption and a rise in incidental oil spillages have become global concerns owing to their aquatic and terrestrial toxicity....  相似文献   
35.
Environmental Science and Pollution Research - Climate change and global warming are the visible consequences of the increased amount of carbon dioxide (CO2) in the atmosphere. Among the various...  相似文献   
36.
Effect of cumulative doses of estradiol -17beta (E2-7, 14 and 28 mg/kg body weight) and 17alpha, 20beta-dihydroxy-4-pregnen-3-one (17alpha,20betaP-7, 14 and 28 mg/kg body weight) on total phospholipids (TP) and various phospholipids- phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE) on liver plasma and ovary were investigated during the reproductively active preparatory and prespawning phases of the annual reproductive cycle in the freshwater female catfish, H. fossilis. The effect of E2 on TP was generally stimulatory and has pronounced effect than 17alpha,20betaP during both the phases. The levels of PC was promoted high during prespawning phase by E2 comparatively very less than by 17alpha, 20betaP in studied tissues during both the phases. The levels of PS after E2 treatments was maximum in all tissues during prespawning phase whereas 17alpha,20betaP was effective only in liver during this phase. The PI was elevated in liver during preparatory phase but its elevation was in all studied tissues during prespawning phase after E2 treatments. The levels of PI was most effective in ovary during preparatory phase in response to 17alpha,20betaP. The levels of PE was declined in liver but elevated in ovary after E2 treatments during both the phases. Treatments of E2 during preparatory phase showed greater number of vitellogenic oocytes as compared to 17alpha,20betaP treatments. The present finding has demonstrated that estradiol-17beta has more pronounced effects than the 17alpha,20beta P in regulation of different phospholipids and ovarian recrudescence during reproductively active phases and among the phospholipids the PC is the main phospholipids of vitellogenin/ovarian lipids in H. fossilis.  相似文献   
37.
We describe the effect of inorganic mercury on the emergence, hatching and growth ofArtemia franciscana (commercially obtained). At concentrations as low as 0.01µmol 1–1, mercury delays development of the organism, but the effect on the final number of developed brine shrimp is small. At higher concentrations, mercury has a dramatic effect, inhibiting the developmental process at the emergence and hatching stages. As recorded by light and scanning electron microscopy, organisms stalled at emergence are not immediately killed. Their eye spots continue to darken and some may hatch although partially enclosed in the cyst shell. Completely emerged prenauplii in the presence of mercury often have an abnormal oval shape while hatched organisms may display shortened and deformed bodies and exhibit restricted movement. The results demonstrate that emergingA. franciscana are very sensitive to inorganic mercury and the potential usefulness of this organism for the study of metal effects upon physiological processes is indicated.  相似文献   
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39.
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   
40.
The oxidation of elemental sulphur in the catalytic presence of selected metal ions [Cr(III), Ce(III), Cu(II), Hg(II), Ni(II), Co(II), Mo(VI), Cd(II), Zn(II), Ti(IV), and V(V)], and hydrocarbons (benzene, gasoline, and kerosene) was studied in an alkaline medium buffered by marble powder. The catalytic efficiencies of metal ions were: Cr(III) > Ce(III) > Cu(II) > Hg(II) > Ni(II). The oxidation process was inhibited in the presence of other ions, and the inhibitive effect was in the following order: Co(II) < Mo(VI) < Cd(II) < Zn(II) < Ti(IV) < V(V). In the case of hydrocarbons, the efficiencies were as follows: gasoline > benzene > kerosene. The oxidation of sulphur in sulphur-loaded soils obtained from near a textile mill and a distillery were also carried out in the c both cases was significantly enhanced.To whom all correspondence should be addressed.  相似文献   
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