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991.
Aquaculture International - Long-term use of the recirculated water for fish and crop production in the aquaponics system that is the major concern in sustainable aquaculture for reduction of the...  相似文献   
992.
Two new bergenin derivatives, named rivebergenin A and B (1, and 2), together with two known compounds, bergenin (3) and norbergenin (4) were isolated from the stem of Rivea hypocrateriformis (Desr.) Choisy. The structures of the new compound have been assigned from 1H and 13C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. Compounds 1-4 showed the strong antioxidant activity.  相似文献   
993.
This study presents new evidence of historic low-to-moderate-severity fires, intermixed with high-severity fires, in the foothills of the Rocky Mountains of west-central Alberta, Canada. High-severity fires that burned 120-300 years ago initiated even-aged cohorts of fast-growing lodgepole pine at each of the six study sites. Evidence of subsequent, low-to-moderate-severity fires included single and double fire scars on thin-barked lodgepole pine that were as small as 3.6 cm in diameter at the time of the fire, but survived. These low-to-moderate-severity fires resulted in structurally complex stands with a broad range of tree diameters and multiple cohorts of lodgepole pine, white and black spruce, and subalpine fir. At the site level, fire return intervals were variable, ranging from 29 to 167 years, but most were <80 years. Of the 9 years in which we documented low-to-moderate-severity fires, only the fires in 1889 and 1915 scarred trees at more than one site, indicating that these fires were small and had local effects. The new knowledge of historical, low-to-moderate-severity fires provided by this study has important implications for ecologically sustainable forest management. Although we recognize that further research needs to determine the extent of low-to-moderate-severity fires at the landscape scale, our results clearly indicate that a mixed-severity fires occurred at least locally. A broader range of silvicultural systems than is currently practiced would be consistent with historic forest dynamics.  相似文献   
994.

Milk has a high nutritional value and can affect human health. Therefore, it is important to know the factors affecting its quality. The purpose of this study was to evaluate the raw milk microbial quality and factors affecting it. A total of 4260 raw cow milk samples, which were collected from villages around Garmsar city, Iran, and their microbial load were registered at Garmsar Dairy Cow Association between 2013 and 2014, was used in the present study. The total average ± SD of microbial load concentration was 3.02?×?105?±?2.75?×?105 (CFU/ml). The average concentration of total bacteria in 2013 was 2.73?×?105?±?1.58?×?105 (CFU/ml) and in 2014 it was 3.32?×?105?±?3.93?×?105(CFU/ml). Seasonally, it was 2.94?×?105?±?1.72?×?105 (CFU/ml), 3.69?×?105?±?4.55?×?105 (CFU/ml), 2.91?×?105?±?1.62?×?105 (CFU/ml), and 2.63?×?105?±?1.67?×?105 (CFU/ml) for spring, summer, autumn, and winter, respectively. There was a significant difference in seasonal average microbial concentration of milk samples (p?<?0.05). The present study concludes that microbial load of milk can be affected by environmental and hygienic conditions. Ranchers need to pay more attention to hygiene especially in warm seasons. Because in case of high microbial load in raw milk, even after milk pasteurization, it is not possible to have a high-quality and desirable product. Milk producers and distributors need also awareness in order to reduce the incidence of secondary contamination. But, the main correction is to establish direct supervision of the Ministry of Health onto the health of dairy cow farmers by structural integrity of Veterinary Medical Organization as the global one health.

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995.
Three field experiments were conducted at the research fields of Plant Protection Research Institute, Iran, at different locations in 2004–2005 to study the efficacy of different broadleaved herbicides to control weeds in wheat. Treatments were the full-season hand weeded and weed-infested controls, and post-emergence applications of florasulam plus flumetsulam at 8.75, 10.50, and 12.25 g a.i./ha, 2,4-D plus carfentrazone-ethyl at 210, 245, 280, and 490 g a.i./ha, bromoxynil plus MCPA at 75, 100, and 150 g a.i./ha, 2,4-D at 560, 720, and 1120 g a.i./ha, tribenuron methyl, and 2,4-D plus MCPA. Herbicides were applied at wheat tillering stage. Naturally occurring broadleaved weed populations were used in experiments. Results indicated that bromoxynil plus MCPA at 150 g a.i./ha, 2,4-D plus MCPA, and 2,4-D plus carfentrazone-ethyl at 490 g a.i./ha were the best options to control weeds. Bromoxynil plus MCPA at 150 g a.i./ha and 2,4-D plus MCPA also resulted in the highest wheat yield. Overall, it could be concluded that rotational application of bromoxynil plus MCPA at 150 g a.i./ha, 2,4-D plus MCPA, and 2,4-D plus carfentrazone-ethyl at 490 g a.i./ha would be the best option to achieve satisfactory weed control, high grain yield and prevention of evolution of herbicide-resistant weeds.  相似文献   
996.
Background: Data shows vanadium protects pancreatic beta cells (BC) from diabetic animals. Whether this effect is direct or through the relief of glucose toxicity is not clear. This study evaluated the potential effect of oral vanadyl sulfate (vanadium) on glycemic status and pancreatic BC of normal and diabetic rats. Methods: Rats were divided into five groups of normal and diabetic. Diabetes was induced with streptozocin (40 mg/kg, i.v.). Normal rats used water (CN) or vanadium (1 mg/ml VOSO4, VTN). Diabetic rats used water (CD), water plus daily neutral protamine Hagedorn insulin injection (80 U/kg, ITD) or vanadium (VTD). Blood samples were taken for blood glucose (BG, mg/dL) and insulin (ng/dL) measurements. After two months, the pancreata of sacrificed rats were prepared for islet staining. Results: Pre-treated normal BG was 88 ± 2, and diabetic BG was 395 ± 9. The final BG in CD, VTD, and ITD was 509 ± 22, 138 ± 14, and 141 ± 14, respectively. Insulin in VTN (0.75 ± 0.01) and VTD (0.78 ± 0.01) was similar, higher than CD (0.51 ± 0.07) but lower than CN (2.51 ± 0.02). VTN islets compared to CN had larger size and denser central core insulin immunoreactivity with plentiful BC. CD and ITD islets were atrophied and had scattered insulin immunoreactivity spots and low BC mass. VTD islets were almost similar to CN. Conclusion: Besides insulin-like activity, vanadium protected pancreatic islet BC, and the relief of glucose toxicity happening with vanadium had a little role in this action. Key Words: Vanadium, Rats, Diabetes, Protection, Beta cells  相似文献   
997.

Abiotic stress has a negative impact on plant physiology, influencing the overall growth and development of plant crops. Saline stress is one of the most serious environmental issues limiting crop plant production. Biofertilizers are reparative elements used in soil to increase tolerance to salinity and drought stress. We investigated the effect of salinity stress on qualitative and quantitative characteristics of cherry tomato plants (Lycopersicon esculentum cerasiforme) with biofertilizer application 0, 15 and 30 days after transplanting in this study. After different days of transplantation, different levels of salinity (0, 50, 100, and 150?mM) were used with biofertilizer (Azospirillum sp. and Azotobacter sp.) application (0, 15 and 30 days). The salinity (150?mM NaCl) significantly affected the studied variables, which were recorded with minimum levels of leaf area (52.42?cm2), root length (6.54?cm), fresh root weight (13.64?g), yield (6.52 tons/ha), leaf chlorophyll content (36.11?mg/m2) and maximum levels of total soluble solids (TSS, 8.87 °Brix). Control samples had higher leaf area (58.35?cm2), root length (15.23?cm), fresh root weight (17.86?g), yield (9.39 tons/ha), leaf chlorophyll content (44.09?mg/m2), and lower TSS (7.93 °Brix). Plants that received biofertilizer (15 days after transplanting) had higher plant height (73.41?cm), stem diameter (0.74?cm), leaf area (61.16?cm2), root length (15.35?cm), fresh root weight (18.38?g), root dry matter (60.41%), yield (10.43?t/ha), leaf chlorophyll content (42.55?mg/m2), fruit dry matter content (10.12?g), pH 4.52, and TSS (9.30 °Brix). The minimum plant height (51.33?cm), stem diameter (0.55?cm), leaf area (49.60?cm2), root length (7.04?cm), fresh root weight (12.76?g), root dry matter (42.16?g), yield (5.15 tons/ha), leaf chlorophyll content (35.18?mg/m2), fruit dry matter content (6.59?g), pH 4.27 and TSS (7.55 °Brix) were recorded in plants with no application of biofertilizer. The present study revealed that most growth and quality variables were negatively affected by salinity except for TSS, which showed positive effect with application of 150?mM of NaCl. Biofertilizer application at 15 days significantly influences the quantitative and qualitative attributes of cherry tomato under different levels of salinity.

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998.
In this paper, urethane polycarboxylate (UPC) as a novel adsorbent was synthesized and characterized. Dye removal ability of UPC from aqueous solution of single and binary systems was studied. Fourier transform infrared (FTIR) was used to characterize UPC. Basic Blue 41 (BB41), Basic Red 18 (BR18), and Basic Violet 16 (BV16) were used as cationic dyes. Dye removal isotherm and kinetic were evaluated. The effect of UPC dosage, initial dye concentration, and inorganic anions on dye removal was investigated. The capacity of UPC to remove BB41, BR18, and BV16 were 333 mg/g, 278 mg/g, and 222 mg/g, respectively. Dye removal kinetics and isotherm using UPC were fitted with the pseudo-second order and Langmuir model, respectively. The results showed the UPC might be used as a dye adsorbent to treat multicomponent systems containing cationic dyes.  相似文献   
999.
Natural rubber and styrene butadiene rubber (NR/SBR) reinforced with both short nylon fibers and nanoclay (Cloisite 15A) nanocomposites were prepared in an internal and a two roll-mill mixer by a three-step mixing process. The effects of fiber loading and different loading of nanoclay (1, 3 and 5 wt. %) were studied on the microstructure and mechanical properties of the nanocomposites. The adhesion between the fiber and the matrix was improved by the addition of a dry bonding system consisting of resorcinol, hexamethylene tetramine and hydrated silica (HRH). This silicate clay layers was used in place of hydrated silica in a HRH bonding system for SBR/NR-short nylon fiber composite. Nanoclay was also used as a reinforcing filler in the matrix-short fiber hybrid composite. The cure and scorch times of the composites decreased while cure rate increased when the short fiber and nanoclay were added. The mechanical properties of the composites showed improvement in both longitudinal and transverse directions with increasing short fiber and nanoclay content. The structure of the nanocomposites was characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM). X-ray diffraction results of nanocomposites indicated that the interlayer distance of silicate layers increased. The mechanical properties of nanocomposites (tensile, hardness and tear strength) are examined and the outcome of these results is discussed in this paper.  相似文献   
1000.
Influence of four rootstocks (M.9, MM.106, MM.111, and local seedling) on the scion leaf and fruit mineral concentrations, tree growth, yield and fruit quality attributes of ‘Golden Delicious’ and ‘Royal Gala’ apples during four seasons (2008–2011) were significant. The mechanisms behind the influence of rootstock on scion vigor and yield was that the rootstock brought about its effects upon the scion by influencing the amounts of minerals taken up and translocated to the scion. ‘Royal Gala’ and ‘Golden Delicious’ trees on seedling had the highest efficiency in calcium (Ca) and potassium (K) uptake. Whereas, trees of these cultivars on M.9 were more efficient in nitrogen (N), manganese (Mn) and iron (Fe) uptake. MM.106 had the highest efficiency in phosphorous (P) uptake, and M.9 had the lowest K and Ca uptake. The highest N- fruit concentration and the lowest Ca-fruit concentration were observed in cultivars on M.9.  相似文献   
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