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Journal of Plant Diseases and Protection - Wireworms, the larvae of Agriotes spp. (Coleoptera: Elateridae), cause serious damage to a number of crops. To develop an effective management strategy, a...  相似文献   
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The concentrations of the hydrogen radicals OH and HO2 in the middle and upper troposphere were measured simultaneously with those of NO, O3, CO, H2O, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HOx required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O3 than expected.  相似文献   
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To promote integrated weed management (IWM) implementation in Europe, robust evidence on the sustainability of such tools and strategies is needed to motivate their adoption by stakeholders. This can only be achieved through assessing and validating them at real farm scale and using existing farm equipment, under diverse climatic and soil conditions representative of European agriculture. In 2013 and 2014, 12 on‐farm experiments (i.e. real field conditions on commercial farms, with natural weed flora) were conducted in four important European grain maize‐producing regions comparing the efficacy of herbicide band application integrated with inter‐row mechanical weeding as a potential IWM tool with the conventional broadcast herbicide application (CON) used by the farms. The IWM tools tested were as follows: (i) early post‐emergence herbicide band application combined with hoeing, followed by a second hoeing in southern Germany, (ii) early post‐emergence herbicide band application followed by hoeing in eastern Hungary and central Slovenia and (iii) pre‐emergence herbicide band application followed by hoeing in northern Italy. Herbicide band application integrated with hoeing provided good and partial weed control along and between maize rows respectively. No significant yield differences were detected between IWM and CON. IWM greatly reduced herbicide input and was economically sustainable over the duration of this study with no significant difference in gross margin compared with CON in all cases. This IWM tool could therefore be considered for implementation in European maize systems.  相似文献   
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An unusual outbreak of contagious ovine ecthyma   总被引:1,自引:0,他引:1  
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Summary The anaesthetic effects of intravenous tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg (TK) and tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg-xylazine 0.11 mg/kg (TKX) were evaluated in six wethers. Heart rate, respiration rate, arterial blood pressure, and the electrocardiogram were monitored during anaesthesia. Analgesia was tested by electrical stimulation in the left flank. Atropine (0.03 mg/kg) was given intramuscularly before induction, but after recording of baseline heart rate and respiratory rate. The duration of analgesia was 28.7 ± 6.9 min with TK and 82.8 ± 26.6 min with TKX. Heart rate increased significantly within 5 min after TK or TKX administration. Respiratory rate remained unchanged after TK administration, but increased significantly from 5 to 45 min after TKX administration. Arterial blood pressure decreased significantly at 15 min with TK and 30 min with TKX. Sheep remained recumbent for 201 min with TK and 166 min with TKX. All recovered uneventfully. We conclude that either TK or TKX may be used for anaesthetising sheep.  相似文献   
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Seed of Adonis microcarpa (pheasant's eye) fed at 5.6 g/kg of the diet induced virtually total feed refusal within 3 d in growing and finishing pigs. It also caused vomiting, rapid and shallow breathing and death in a minority. These effects were probably caused by cardiac glycosides whose structure and effects closely resemble those of digoxin. Feed intake and growth recovered within 2 weeks of removal of the seed.  相似文献   
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