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71.

Purpose  

There is considerable interest in finding a cost-effective method of site preparation that effectively controls weeds during planting and further reduces the need for recurring herbicide applications. In this study, two weed control methods, herbicide and scalping, were examined. Both methods may have implications for soil organic matter (SOM) dynamics and nitrogen (N) which could consequently affect plant survival and vegetation establishment. This study aimed to investigate the dynamics of SOM, carbon (C) and N pools under site manipulation practices and the associated early plant survival and growth in tropical Australia.  相似文献   
72.
Topography has an important influence on the distribution of soils and their properties, especially in hilly lands, and related data are easily available, measurable and recognizable from digital elevation models (DEMs). To our knowledge, little attention has previously been paid to the effect of DEM attributes on the distribution of soils, using ordination methods. The objective of this study was to analyze relationships between topographical properties derived from DEM and soil distribution and to discuss their applicability in Digital Soil Mapping (DSM). The study was carried out in the Borujen area of central Zagros, Iran. A total of 13 plots (each one of 6.75 ha) were set up to calculate the percentages of the dominant soil series. Fifteen DEM attributes, including slope, aspect, curvature, maximum and minimum curvature, planform curvature, profile curvature, tangent curvature, wetness index, power index, sediment index, area solar radiation, direct radiation, diffuse radiation and direct duration were also computed. Canonical Correspondence Analysis (CCA) was used to summarize the data set and to evaluate the expected relationships. The results obtained show that there was a relatively strong correspondence between soils' series distribution and topographical properties. The DEM attributes that best related to the first axis were maximum curvature, slope and sediment index, all of which significantly positive correlated, and wetness index, direct duration and minimum curvature, all of which were negatively related. The second axis showed a negative trend with wetness index, direct duration and aspect, and a positive trend with sediment index and slope. These gradients were closely related to the first three canonical axes and explained 71.8% of the total variance of the soil series. The residual variance (28.2% of the total variance) was related to other soil forming factors, like parent material and vegetation cover, which were not investigated in this study. Considering that DEMs are still the most important source of environmental information, understanding the role of topographical factors in a region should help us to identify soils and their properties better and enable us to apply these derivates as input data in DSM.  相似文献   
73.
In the present study, we examined the mortality rate, egg production, and clinical signs of quail experimentally infected with a field isolate of A/Chicken/Iran/339/02 (H9N2) avian influenza virus obtained from an infected commercial layer farm with severe morbidity and mortality. A total of 120 quail at 14 days old were randomly divided into four groups of vaccinated (B and C) and unvaccinated (A and D) birds. Vaccination was done on days 20 and 32, and viral inoculation of birds in groups C and D was then carried out on day 43. For evaluation of viral transmission, at 24 hr postinoculation additional unvaccinated birds were placed in direct contact with challenged birds. All the birds were evaluated for clinical signs, egg production, antibody production, viral titration in lung homogenates, and viral transmission following inoculation. All unvaccinated-challenged birds were infected and showed clinical signs, whereas the infection rate along with clinical signs of vaccinated-challenged birds reached 30%-40%. Although vaccination induced high antibody titers, reduction in food and water consumption was evident in this vaccinated-challenged group compared with the unchallenged control group. These results could indicate that inactivated vaccine did not fully prevent the infection, although it was capable of protecting birds against clinical signs and significantly decreased viral titers in lungs after intranasal challenge.  相似文献   
74.
The aim of this study was to evaluate the effects of different concentrations of lycopene and cysteamine on characteristics of sperm, liquid peroxidation and enzymatic activities in seminal plasma of canine semen preserved at 5°C for 72 hr. The semen samples were divided into eight aliquots: control, control sham (dimethyl sulfoxide 5%), lycopene groups (250, 500 and 750 µg/ml) and cysteamine groups (2.5, 5 and 10 mM). Motility, viability, membrane integrity, DNA integrity, total antioxidant capacity (TAC) and malondialdehyde (MDA) levels were evaluated. Progressive motility and total motility were higher with the 500 and 750 µg/ml lycopene concentrations, respectively, compared to the control group and the cysteamine groups following 72 hr of storage in the liquid storage. Motility characteristics, viability and hypo-osmotic swelling test (HOST) percentages were significantly improved in 500 µg/ml lycopene compared to other groups. The 500 and 750 µg/ml lycopene concentrations, respectively, showed significantly reduced percentages of spermatozoa with DNA integrity compared to the control group. The 500 and 750 µg/ml lycopene concentrations, respectively, led to the significant decrease of MDA levels. The 500 µg/ml lycopene enhanced TAC levels after 48 and 72 hr that was not observed in other groups. In conclusion, the findings of this study showed that lycopene supplementation in canine semen extenders improved canine semen parameters and TAC levels and decreased MDA levels in the chilling process.  相似文献   
75.
Tropical Animal Health and Production - The aims of this study was to evaluate inbreeding effects for growth rate (average daily gain from hatch to 8 weeks of age (ADG1–8), average...  相似文献   
76.
The use of organic residue is appropriate in maintaining long-term phosphorus (P) requirement of crops. This study was conducted to investigate the effect of time and organic residue addition on P availability in some calcareous soils. Five plant residues and two manures in a wide range of C/N ratios were added to the soil samples at rates of 20 g kg?1 soil. The samples were incubated for 2, 72, 336, 672, 1440, and 2160 hours at constant temperature and moisture. Extractable phosphorus (Olsen-P) was determined after the incubation. There were decreases in the Olsen-P in all five amended soils during 2160 hours of incubation. The power model was found to be suitable to describe P transformation rates from amended soils. The constant b in the power model of P for amended soils was defined as transformation rate were in the order (average of five soils) vegetables waste > sheep manure > potato > poultry manure > sunflower > rape > weeds residues. There were significant correlations between C/P in residues and parameters a and parameter b. There were significant correlations between clay content and calcium carbonate and transformation rate of P in soils. The model parameters of P are suitable to estimate the P-fertilizer effect of organic residues.  相似文献   
77.
Perioperative hyperglycemia is common in patients with type 2 diabetes undergoing Coronary Artery Bypass Graft (CABG) surgery and there is a direct relation between postoperative hyperglycemia and mortality rate in these patients. The aim of the present study is to determine the efficacy of metformin on glycemic control in diabetic patients after CABG surgery. In a randomized double blind clinical trial, 100 patients with type 2 diabetes admitted in open heart ICU after CABG surgery in Mazandaran Heart Center were enrolled. They were randomly assigned to two intervention and control groups. Three hours after extubation, therapeutic antiglycemic regimens were applied in these two groups and continued for three days. Intervention group received regular insulin infusion along with two metformin 500 mg tablets per twelve hours while control group received regular insulin infusion with two placebo tablets per twelve hours. Blood glucose level and other parameters were measured and recorded in determined intervals. To analyze the data, independent T-test, paired T-test, Mann-Whitney and repeated measure ANOVA tests were employed. Mean blood glucose level was not significantly different in the two groups at the beginning of the ICU admission; however, mean glucose level in insulin-metformin group, twelve hours after the initiation of the study, was significantly lower than insulin group (p < 0.05). In addition, mean doses of potassium and insulin demand as well as mean number of episodes of hyperglycemia, hypoglycemia and glucose levels out of the accepted range were significantly lower in insulin-metformin group (p < 0.05). Alterations in mean levels of lactate, BE, pH and creatinine were not statistically significant in these two groups. It seems that adding metformin to insulin leads to a better glycemic control in type two diabetic patients undergoing CABG surgery without causing metabolic acidosis. Therefore, it might be a potential option in blood glucose control protocol in this group of patients.  相似文献   
78.
Knee osteoarthritis is the most common cause of disability among people and it is a common disease of joints that can lead to cartilage damage. In this study the analgesic effects of a herbal ointment containing cinnamon, ginger, mastic (Saghez) and sesame oil is compared with Salicylate ointment in patients suffering from knee osteoarthritis. It was a double-blind randomized controlled trail study. Patients with diagnosed arthritis were involved in the study and they were divided in two groups via block randomization method. For six weeks, twice a day, intervention group applied herbal ointment and control group used Salicylate ointment. The severity of pain, morning stiffness and limited motion were measured using Visual Analog Pain Scale. In order to analyze the trends of these three indexes, repeated measurement test was used. Ninety two participates with the mean age of 52.2 (+/- 12.4) years and with the mean disease period of 30.45 (+/- 30.3) months were involved in the study. There was no significant difference between two groups regarding the distribution of sex, weight, height, BMI and the duration of illness. No statistical difference was observed between two groups regarding pain relief, morning stiffness and limited motion; nevertheless in repeated measurements during second, forth and sixth weeks in both groups the decreasing trend of these three indexes had been statistically significant (p < 0.0001). It seems that using this herbal combination is clinically effective for patients suffering from knee osteoarthritis in order to decrease their pain, morning stiffness and limited motion; its effect is comparable with Salicylate ointment.  相似文献   
79.

The aim of this study was to evaluate the water and nitrogen use efficiency and some quantitative and qualitative characteristics of forage beet cultivars under the influence of different irrigation methods and nitrogen levels in two cropping years, 2017–18 and 2018–19, at Agricultural Research Station in Karaj, Iran. Experimental factors included the first factor with four irrigation methods (normal leakage, alternate furrow irrigation, fixed furrow irrigation, type (drip-strip)), the second factor was the amount of nitrogen fertilizer with three levels (150, 200 and 250?kg N ha?1) and the third factor included three forage beet cultivars (Sbsi052, Jamon and Kyros). Among irrigation treatments, alternate furrow irrigation and fixed furrow irrigation had the highest sugar content with 9.28% and 9.17%, respectively. The highest yield of digestible organic matter was obtained in leakage irrigation treatment, nitrogen fertilizer of 250?kg ha?1 and in Kyros at the rate of 19.45?t ha?1. The highest yield of root digestible dry matter, potassium, sodium and free nitrogen was observed in leakage irrigation treatment and consumption of 200?kg ha?1 nitrogen was observed in foreign cultivars. The highest crude protein was observed in alternate furrow irrigation conditions with a consumption of 200?kg ha?1 nitrogen in cultivar Sbsi052 at 13.08%. Leakage irrigation and type tape had the highest consumption efficiency and efficiency of nitrogen uptake with application of 150 and 200?kg ha?1 N, and the highest water use efficiency was also observed in leakage irrigation and type tape with application of 250?kg ha?1 N in domestic and foreign cultivars. The type irrigation method showed better quantitative and qualitative yield than the furrow irrigation methods.

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80.
European Journal of Plant Pathology - The effects of three biological control agents (BCAs) including Funneliformis mosseae BEG12 (FM) as arbuscular mycorrhizal fungi (AMF), Bacillus velezensis...  相似文献   
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