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21.
An experiment was conducted to study the effect of heavy disc harrowing in combination with chisel ploughing to depths of 10, 20, and 30 cm, on soil physical properties, cane yield, and sugar yield. The experiment was executed in two non-fallow, two semi-fallow and one fallow field conditions, in Kenana Sugar Estate, Sudan.

Results showed that the final surfaces for all tillage treatments were clean and smooth. Percent residue cover ranged from 4.2 to 5.4. After seedbed preparation percent clods greater than 1 cm in diameter ranged from 31.1 to 35.8, while gravimetric moisture content in the tillage zone ranged from 29.9 to 30.5. No significant differences were observed between treatments in residue cover, clod size and moisture content.

Soil penetration resistance in the five sites measured after the last irrigation showed no significant differences. Cone index ranged from 802 to 934 kPa. Bulk density measurements also showed no significant differences between tillage treatments.

Yield data showed that chisel ploughing to depths of 20 and 30 cm before disc harrowing, significantly increased cane and sugar yields than conventional tillage at Kenana. The highest field productivity (105.27 Mg ha−1) was obtained with the combined disc harrowing and 20 cm chisel ploughing. Yield of cane per hectare under this method was 8.38 Mg ha−1 higher than that under the conventional method. Sugar yield per hectare increased by 1 metric ton, which was 8.6% higher than that of the conventional method.

The relation between tillage depth (x) and cane yield (Y), in tons of cane per hectare, for average Kenana field condition could be expressed by the third-order polynomial:

Y=158.141−7.725x+0.293x2−0.003x3
The fallow, semi-fallow and non-fallow sites were not significantly different in cane yield.

All tillage methods studied were more intensive than adequate levels for soil conservation practices found in the reviewed literature; it is suggested to omit the re-harrowing operation of Kenana conventional tillage.  相似文献   

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Background: Forests are fundamental in maintaining water supplies, providing economic goods, mitigating climate change, and maintaining biodiversity, thus providing many of the world’s poorest with income, food and medicine.Too often, forested lands are treated as "wastelands" or "free" and are easily cleared for agricultural and infrastructure expansion.Methods: In this paper, the sustainability of two forest ecosystems(state and community/private owned) was evaluated using SPOT-5 satellite images of 2005 and 2011. This study was conducted in a sub-watershed area covering 468 km2, of which 201 km2 is managed by the state and 267 km2 by community/private ownership in the Murree Galliat region of Punjab Province of Pakistan. A participatory approach was adopted for the delineation and demarcation of forest boundaries. The Geographic Object-Based Image Analysis(GEOBIA) technique was used for identification and mapping of ten Land Cover(LC) features.Results: The results show that between the years 2005 to 2011, a total of 55 km2(24 km2 in state-owned forest and 31km2 in community/private forest) was converted from forest to non-forest. The conclusion is that conservation is more effective in state-owned forests than in the community/private forests.Conclusions: These findings may help to mobilize community awareness and identify effective initiatives for improved management of community/private forest land for other regions of Pakistan.  相似文献   
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Current study was conducted to identify constituents of Taxus wallichiana Zucc. that might be responsible for its folk use in anti-inflammatory conditions. Taxusabietane A was isolated from the bark extract of Taxus wallichiana Zucc. Taxusabietane A was analyzed for in-vitro and in-vivo anti-inflammatory activities using Lipoxygenase (LOX) inhibition assay and carrageenan-induced paw edema model. Taxusabietane A revealed considerable LOX inhibitory activity with the IC50 value being 57 ± 0.31. Standard compound Baicalein showed the IC50 value being 22.1 ± 0.03 μM. Taxusabietane A also showed significant (5 and 10 mg/kg) anti-inflammatory activity induced by carrageenan. However, this study highlighted the potential of Taxusabietane A to be further explored as a new lead compound for management of conditions associated with inflammation.  相似文献   
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Nonpathogenic and opportunistic bacteria are increasingly recognized as reservoirs of antibiotic resistance genes. However, nothing is known about the mechanisms of antibiotic resistance in such bacteria isolated from the udders of healthy animals. In this study, 150 Gram-negative strains isolated from milk samples of healthy dairy cows were screened for the presence of a large pool of antibiotic resistance markers. Strains carrying β-lactamase-resistance genes, including SHV-1, SHV-11, SHV-27, TEM-1, OXY-1, CTX-M-2 and class 1 integrons, were detected. Our findings give the first evidence that nonpathogenic and opportunistic bacteria carrying antibiotic resistance genes can asymptomatically invade healthy udders and suggest that they may play a role in the dissemination of antibiotic resistance genes to the other udder pathogens.  相似文献   
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Janbaz KH  Saeed SA  Gilani AH 《Fitoterapia》2002,73(7-8):557-563
Rutin, a well-known flavonoid was investigated for its possible protective effect against paracetamol- and CCl(4)-induced hepatic damage. Paracetamol produced 100% mortality at the dose of 1 g/kg in mice while pre-treatment of animals with rutin (20 mg/kg) reduced the death rate to 40%. Oral administration of a sub-lethal dose of paracetamol (640 mg/kg) produced liver damage in rats as manifested by the rise in serum level of transaminases (AST and ALT). Pre-treatment of rats with rutin (20 mg/kg) prevented the paracetamol-induced rise in serum enzymes. The hepatotoxic dose of CCl(4) (1.5 ml/kg; orally) also raised the serum AST and ALT levels. The same dose of rutin (20 mg/kg) was able to prevent the CCl(4)-induced rise in serum enzymes. Rutin also prevented the CCl(4)-induced prolongation in pentobarbital sleeping time confirming its hepatoprotectivity. These results indicate that rutin possesses hepatoprotective activity and the presence of this compound in Artemisia scoparia may explain the folkloric use of the plant in liver damage.  相似文献   
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1. A study was conducted to investigate the effect of environment on ranging in 33 flocks reared with (16) or without (17) range access. Ranging was observed at 8, 16 and 35 weeks. Information on house layout, weather conditions and range characteristics was used to create models predicting the percentage of the flock out on the range and the percentage of ranging birds observed away from the house.

2. Three flocks had range access at 8 weeks. The percentage of birds ranging averaged 28%, with 22% of these ranging away from the house. For the 13 flocks with range access at 16 weeks, the percentage of pullets on the range was 12%, with 29% of these ranging away from the house. At 35 weeks, all flocks had range access and the average percentage of birds out on the range was 13%, with 42% of these ranging away from the house.

3. The percentage of birds seen using the range was higher with reduced flock size and stocking density, increased pop hole availability (cm/bird) and light intensity inside the house. More birds ranged on cooler days and on farms located in areas with fewer days of rain per year and lower average rainfall. The percentage of birds ranging varied with season and was lowest in May. More birds ranged away from the house when cover and more artificial structures were present on the range. The proportion of ranging birds located away from the house increased with lower outdoor humidity levels, higher air pressure, and on warmer days. Lastly, birds ranged away from the house more as they got older.  相似文献   

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Gesunde Pflanzen - Foliar application of micronutrients and plant growth regulators (PGRs) is one of the strategies of plant-feeding direct through leaves to allow rapid uptake irrespective of soil...  相似文献   
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