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41.
Paclobutrazol (2R,3R + 2S,3S)-1-(4 chlorophenyl)-4,4-dimethyl-2-(1,2,4-trizol-1-yl) pentan-3-ol), at 25, 50 and 150 mg active ingredient, was applied as a soil drench or stem application to 1-year-old ‘Topred Delicious’ apples. Root growth measured as relative root surface area was reduced by both soil and stem applications. There was no significant difference in dry weight of the root tissue. The root-to-leaf-area ratio was significantly increased in paclobutrazol-treated plants.Water relations measured as leaf conductance and leaf water potential were significantly influenced by paclobutrazol. Leaf conductance was higher in paclobutrazol-treated plants when the plants were turgid, as well as under some water stress. Leaf water potential was significantly higher in treated plants.There were no significant differences in the total nitrogen, phosphorus, potassium and magnesium levels found in the leaf or root tissue.  相似文献   
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A retrospective survey was carried out at a Florida racetrack in 1984, to determine the prevalence of exercise-induced pulmonary hemorrhage (EIPH) in Appaloosa horses. Of 94 horses examined endoscopically between 30 and 90 minutes after racing, forty-nine (52%) were found to exhibit some degree of EIPH. There was a significantly increased prevalence of EIPH with increasing age in this population. An increased prevalence of EIPH was noted with mares and geldings as compared with stallions, but this was not statistically significant. More horses bled from the right lung than from the left, but the difference was statistically insignificant. An increased prevalence of EIPH with distance run was evident, but this was not significant when animals of the same age were examined.  相似文献   
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Salal (Gaultheria shallon Pursh), which is widely used for floral greenery, is an important non-timber forest product (NTFP) from the coastal forests of the Pacific Northwest of North America. However, there are no known studies on the impacts of commercial salal harvesting on subsequent growth. A study was therefore initiated to quantify the growth of salal 1 year after commercial harvesting, and to compare this with growth of unharvested salal. The amount of biomass removed from shrubs through commercial harvesting (131 g m−2) was the same as the amount of annual growth in adjacent undisturbed plots (135 g m−2). One year later, the amount of regrowth in previously harvested plots (144 g m−2) was greater than the amount of new growth in adjacent undisturbed plots (111 g m−2). As there was little difference in the weight per current stem, the increased biomass after commercial harvesting was attributed to the observed increase in stem number (60 stems m−2) as compared to undisturbed salal (50 stems m−2). Our study does not incorporate either repeated annual harvesting or variable harvesting intensities, both of which have been anecdotally reported to affect levels of re-growth and therefore sustainability.  相似文献   
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The fate of benzofenap [2-[4-(2,4-dicholoro-m-toluoyl)-1,3-dimethylpyrazol-5-yloxy]-4'-methylacetophenone] applied to flooded rice was studied at two locations in New South Wales (Australia). Solid-phase extraction (SPE) was compared with liquid-liquid extraction (LLE) for the determination of the commercial chemical in water samples. SPE performed well as compared to LLE (84 vs 80%) in irrigation waters. However, at the lower end of the concentration range (3 microg/L), LLE achieved higher recoveries than SPE (72 vs 59%). Rates of dissipation (DT50) from floodwaters and soils were measured. Dissipation of the herbicide from water and soil occurred fairly erratically in both mediums and can be best explained by a first-order decay process. The DT50 value for benzofenap was <1 day in irrigation water due to rapid deposition of the suspension concentrate formulation. The DT50 in surface soil was 44 days. The maximum measured concentration of benzofenap in a rice field floodwater was 39 microg/L, taking approximately 32 days to dissipate to <1 microg/L.  相似文献   
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OBJECTIVE: To evaluate the feasibility of undertaking a food skills intervention study in areas of social deprivation aimed at altering cooking confidence, food preparation methods and dietary choices. DESIGN: A standardised skills programme was implemented in community-based settings. Pre- (T1) and post-intervention (T2) and 6-month follow-up (T3) measures (7-day diaries and self-administered questionnaires) were undertaken in intervention and comparison groups. SETTING: Eight urban communities in Scotland. SUBJECTS: One hundred and thirteen adults living in areas of social deprivation. RESULTS: It was clear that many subjects led fragmented lives and found commitment to intervention classes problematic. Sixty-three subjects completed the final (T3) assessments. The response to each component varied due to inability to attend sessions, illness, study requirements, employment, moving out of the area, change in circumstances, loss of interest and loss of postal questionnaires. At baseline, reported consumption of fruit and vegetables was low (mean frequency 8.1 +/- 4.78 times per week). Fruit intake increased significantly (P < 0.05) between T1 and T2 in the intervention group (1.7 +/- 2.36 to 2.7 +/- 3.28 times per week) only. Between T1 and T3, there was a significant increase (P < 0.05) in intervention subjects who reported confidence in following a recipe (67-90%,). CONCLUSIONS: This exploratory trial shows that a food skills intervention is likely to have a small but positive effect on food choice and confidence in food preparation. A full-scale randomised controlled trial in this hard-to-reach group would require a range of flexible approaches rather than a fully defined intervention, and presents challenges for trial design.  相似文献   
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With an apparent increase of harmful algal blooms (HABs) worldwide, healthcare providers, public health personnel and coastal managers are struggling to provide scientifically-based appropriately-targeted HAB outreach and education. Since 1998, the Florida Poison Information Center-Miami, with its 24 hour/365 day/year free Aquatic Toxins Hotline (1–888–232–8635) available in several languages, has received over 25,000 HAB-related calls. As part of HAB surveillance, all possible cases of HAB-related illness among callers are reported to the Florida Health Department. This pilot study evaluated an automated call processing menu system that allows callers to access bilingual HAB information, and to speak directly with a trained Poison Information Specialist. The majority (68%) of callers reported satisfaction with the information, and many provided specific suggestions for improvement. This pilot study, the first known evaluation of use and satisfaction with HAB educational outreach materials, demonstrated that the automated system provided useful HAB-related information for the majority of callers, and decreased the routine informational call workload for the Poison Information Specialists, allowing them to focus on callers needing immediate assistance and their healthcare providers. These results will lead to improvement of this valuable HAB outreach, education and surveillance tool. Formal evaluation is recommended for future HAB outreach and educational materials.  相似文献   
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Journal of Pest Science - The advent of ‘conservation agriculture’ (CA) farming using zero- or no-tillage practices and an accompanying change in crop rotations in the last...  相似文献   
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