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21.
We present evidence, based on an ensemble of integrations with NSIPP1 (version 1 of the atmospheric general circulation model developed at NASA's Goddard Space Flight Center in the framework of the Seasonal-to-Interannual Prediction Project) forced only by the observed record of sea surface temperature from 1930 to 2000, to suggest that variability of rainfall in the Sahel results from the response of the African summer monsoon to oceanic forcing, amplified by land-atmosphere interaction. The recent drying trend in the semiarid Sahel is attributed to warmer-than-average low-latitude waters around Africa, which, by favoring the establishment of deep convection over the ocean, weaken the continental convergence associated with the monsoon and engender widespread drought from Senegal to Ethiopia.  相似文献   
22.
Abstract

In recent decades, chemical fertilizers create a thread to organic agriculture and food security. To overcome this issue, the present study aimed to investigate the influence of liquid seaweed extracts (LSEs) prepared from Padina boergesenii (PB) and Gracilaria edulis (GE) on growth, development, biochemical characteristics and yield traits of foxtail millet. The various concentrations of individual (20, 40, 60, and 80%; v/v) and combined (10?+?10, 20?+?20, 30?+?30, and 40?+?40%; v/v) PB and GE LSEs were supplied through foliar spray method. The results imply that germination bioassays, vegetative plant growth were significantly increased in lower concentration of LSEs. Further, exposure of foxtail plants to combined foliar spray application of (20?+?20%; v/v) LSEs enriched photosynthetic pigments, total soluble sugar and total soluble protein, compared with single LSEs and control foliar spray methods. Additionally, LSEs enhanced the yield attributes such as the average number of seeds (971.5/panicle) and mean length of panicle (18.4?cm) in PB?+?GE LSEs (20?+?20%; v/v) treatment. This is the first report, to assess the synergistic biostimulant ability of PB and GE LSEs in plant growth, quality improvement and yield attributes of foxtail millet. In conclusion, this present study suggests that combination of PB?+?GE LSEs foliar spray application could serve as an ideal biostimulant and a potential alternate to hazards chemical fertilizer in the green agriculture.  相似文献   
23.
The extensive use of pharmaceuticals in human and veterinary medicine may enter the aquatic environment and pose a serious threat to non-target aquatic organisms like fish. In this study, Indian major carp Cirrhinus mrigala was exposed to different concentrations (1, 10 and 100 μg L?l) of most commonly used pharmaceutical drugs clofibric acid (CA) and diclofenac (DCF) to evaluate its impacts on certain enzymological parameters during short- and long-term exposures. During short-term (96 h) exposure period, plasma glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and gill Na+/K+-ATPase activity were significantly altered at all concentrations of both the CA- and DCF-treated fish. In long-term exposure (35 days), gill Na+/K+-ATPase activity was found to be significantly increased at all concentration of CA and DCF exposures throughout the study period (except at the end of 7th day in 10 and 100 µg L-1) . However, a biphasic trend was observed in plasma GOT and GPT activity when compared to the control groups. In both short- and long-term exposure, a significant (P < 0.01 and P < 0.05) changes were observed in all enzymological parameters of fish C. mrigala exposed to different concentrations of CA and DCF. The alterations of these enzymological parameters can be effectively used as potential biomarkers in monitoring of pharmaceutical toxicity in aquatic environment and organisms.  相似文献   
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25.
Tropical Animal Health and Production - The low potency of genetic immunization has to date impeded development of commercial vaccines against major infectious diseases. The aim of this study was...  相似文献   
26.
The aim of the present study was to evaluate the possible protective effects of S-allyl cysteine (SAC) on the antioxidant defense system of pancreas in streptozotocin(STZ) induced diabetes in rats. The levels of blood glucose and TBARS in plasma and pancreas were estimated in control and experimental groups of rats. To assess the changes in the cellular antioxidant defense system, the level of reduced glutathione in plasma and pancreas and activities of superoxide dismutase and catalase were assayed in pancreatic tissue homogenate. The levels of glucose, TBARS and enzymatic antioxidants were altered in diabetic rats. These alterations were reverted back to near control levels after the treatment of SAC. The antidiabetic and antioxidant effect of SAC was compared with glyclazide, a well-known hypoglycemic drug. These findings suggest that SAC treatment exerts a therapeutic protective nature in diabetes by decreasing oxidative stress.  相似文献   
27.
When small numbers of colloidal microspheres are attached to the surfaces of liquid emulsion droplets, removing fluid from the droplets leads to packings of spheres that minimize the second moment of the mass distribution. The structures of the packings range from sphere doublets, triangles, and tetrahedra to exotic polyhedra not found in infinite lattice packings, molecules, or minimum-potential energy clusters. The emulsion system presents a route to produce new colloidal structures and a means to study how different physical constraints affect symmetry in small parcels of matter.  相似文献   
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29.
Steps taken for broodstock development of Neopomacentrus nemurus, Coral demoiselle (Bleeker, 1857) in a hatchery, its spawning and development of egg to the juvenile stage are described. Among the three treatments tried, only the trial using Parvocalanus crassirostris nauplii as the first diet helped in the development of larvae. Larval and post‐larval growth was studied for a period of 65 days post hatch. The larva measured 2–2.4 mm in total length at the time of hatching. The mouth size of larva at the time of hatching measured 237.92 µm. By the 5th day, the width of the larval body had significantly increased. All the fins were conjoined, except for the caudal fin which had begun its appearance on the 2nd day itself. The digestive system was functional by the 5th day and the copepod remains were seen in the digestive tract. The larva metamorphosed by the 15th day with fully developed fins and fin rays. On the 20th day, the larval body had begun to display signs of fin pigmentation. The larva assumed adult pigmentation by the 35th day. By the 65th day, the larva grew to a total length of about 27 mm and weighed about 0.56 g.  相似文献   
30.
The present investigation is focused on potential use of banana pseudostem (BPS), which otherwise is disposed off as a waste or incinerated, as a source of polyphenols or antioxidants. The total phenolics (TP) and total flavonoids (TF) in various solvent extracts of pseudostem (PS) of different banana cultivars varied from 7.58 to 291 mg gallic acid equivalent (GAE/g of extract) and from 4 to 80 mg catechin equivalent (CE/g of extract), respectively. Acetone extract showed high antioxidant activity (AOA) in all of the in vitro models tested, whereas methanol extract exhibited high metal chelating activity. Among the banana cultivars, Nanjanagudu Rasabale (NR) showed the highest TP (291 mg GAE/g of extract), TF (80 mg CE/g of extract), and AOA. A detailed study on phenolic acids by reverse phase HPLC and ESI-MS revealed the presence of phenolic acids such as gentisic acid, (+)-catechin, protocatechuic acid, caffeic acid, ferulic acid, and cinnamic acid in cultivar NR. The differences in AOA of banana cultivars are in accordance with their phenolic and flavonoid concentrations.  相似文献   
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