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排序方式: 共有469条查询结果,搜索用时 15 毫秒
91.
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Nicholas Clarke Silje Skår O. Janne Kjønaas Kjersti Holt Hanssen Tonje Økland Jørn-Frode Nordbakken 《Scandinavian Journal of Forest Research》2018,33(3):299-307
Short-term (three to four years) effects of forest harvesting on soil solution chemistry were investigated at two Norway spruce sites in southern Norway, differing in precipitation amount and topography. Experimental plots were either harvested conventionally (stem-only harvesting, SOH) or whole trees, including crowns, twigs and branches were removed (whole-tree harvesting, WTH), leaving residue piles on the ground for some months before removal. The WTH treatment had two sub-treatments: WTH-pile where there had been piles and WTH-removal, from where residues had been removed to make piles. Increased soil solution concentrations of NO3–N, total N, Ca, Mg and K at 30?cm depth, shown by peaks in concentrations in the years after harvesting, were found at the drier, less steep site in eastern Norway after SOH and WTH-pile, but less so after WTH-removal. At the wetter, steeper site in western Norway, peaks were often observed also at WTH-removal plots, which might reflect within-site differences in water pathways due largely to site topography. 相似文献
93.
A NOVEL,REMOVABLE, CERROBEND,BEAM‐BLOCKING DEVICE FOR RADIATION THERAPY OF THE CANINE HEAD AND NECK: PILOT STUDY
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Michael S. Kent Davide Berlato Isabelle Vanhaezebrouck Ira K. Gordon Katherine S. Hansen Alain P. Theon Randall W. Holt Earl A. Trestrail 《Veterinary radiology & ultrasound》2017,58(1):100-105
Radiation therapy of the head and neck can result in mucositis and other acute affects in the oral cavity. This prospective pilot study evaluated a novel, intraoral, beam‐blocking device for use during imaging and therapeutic procedures. The beam‐blocking device was made from a metal alloy inserted into a coated frozen dessert mold (Popsicle® Mold, Cost Plus World Market, Oakland, CA). The device was designed so that it could be inserted into an outer shell, which in turn allowed it to be placed or removed depending on the need due to beam configuration. A Farmer type ionization chamber and virtual water phantom were used to assess effects of field size on transmission. Six large breed cadaver dogs, donated by the owner after death, were recruited for the study. Delivered dose at the dorsal and ventral surfaces of the device, with and without the alloy block in place, were measured using radiochromic film. It was determined that transmission was field size dependent with larger field sizes leading to decreased attenuation of the beam, likely secondary to scatter. The mean and median transmission on the ventral surface without the beam‐blocking device was 0.94 [range 0.94–0.96]. The mean and median transmission with the beam‐blocking device was 0.52 [range 0.50–0.57]. The mean and median increase in dose due to backscatter on the dorsal surface of the beam‐blocking device was 0.04 [range 0.02–0.04]. Findings indicated that this novel device can help attenuate radiation dose ventral to the block in dogs, with minimal backscatter. 相似文献
94.
A quantitative model for trade pathway analysis of plant pest entry and transfer to a host in European Union territory
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J. Holt A. W. Leach A. MacLeod D. Tomlinson M. Christodoulou J. D. Mumford 《EPPO Bulletin》2017,47(2):220-226
A quantitative pathway model, QPAFood, has been designed to support risk assessment for plant pest entry into European Union (EU) territory on a range of edible plant commodities via trade flows. The model calculates the distribution of an imported infested/infected commodity along a pathway into and within the EU from source countries, based on Eurostat data and other data/information. The model determines the implications of global trade pathways for the potential arrival of the infested commodity in the EU28 Member States. Within each Member State, the calculation proceeds by distributing the commodity according to uses, notably retail or processing, to the vulnerable area of commercial host crops determined in each NUTS2 region and then quantifies the consequent potential for pest–host contact which could lead to pest transfer. Annual and monthly estimates of contact risk are tabulated and visualized for Member States and NUTS2 regions. The model was developed originally for the European Food Safety Authority using four case studies of specific pest–commodity combinations. These pests had relatively limited host ranges and the model has now been extended in the context of the EC FP7 DROPSA project for the multiple commodity pathways associated with the highly polyphagous fruit pest Drosophila suzukii. 相似文献
95.
AEM Horta JP Barbas CC Marques MC Baptista MI Vasques RM Pereira RD Mascarenhas S Cavaco‐Gonçalves 《Reproduction in domestic animals》2010,45(6):e412-e416
The effect of vaginal administration of misoprostol plus terbutaline sulphate 6 h prior to artificial insemination (AI) upon the site of AI (vaginal or cervical) and fertility was studied using a total of 87 estrous synchronized Serra da Estrela ewes (control n = 42 and treated n = 45). Artificial insemination was performed using refrigerated semen at 54–55 h after sponge removal. Lambing rate (fertility) and prolificacy were compared between control and treated ewes. The effect of the site of semen deposition on fertility was also evaluated. Prolificacy rate was not different between control (1.5) and treated (1.59) ewes. The proportion of cervical AI achieved in control (45.2%) and treated (37.8%) ewes was not significantly different. Overall, fertility was significantly lower in control than in treated ewes (42.9% vs 64.4%; p < 0.04). Fertility following vaginal AI was significantly lower for control for than treated ewes (30.4% vs 60.7%; p < 0.03) but the difference was smaller and not significant for cervical AI (control 57.9% vs 70.6%). It was concluded that vaginal administration of misoprostol plus terbutaline sulphate 6 h prior to artificial insemination did not affect the proportion of cervical inseminations but significantly improved the fertility of treated ewes. Although needing confirmation, it was hypothesized that drugs might have induced local secretory modifications leading to an increase of cervical ability to retain more viable spermatozoa for fertilization. 相似文献
96.
97.
Mithril C Dragsted LO Meyer C Blauert E Holt MK Astrup A 《Public health nutrition》2012,15(10):1941-1947
98.
Objective: To describe preoperative use of skin stretchers to elongate a peninsular thoracodorsal axial pattern flap to close a large antebrachial wound on a dog. Study Design: Case report. Animals: A 21 kg, 7‐year‐old, male intact mixed breed dog. Methods: Two skin stretchers were applied to the site of the thoracodorsal axial pattern flap 4 days before surgery. The elastic cables connecting the adhesive pads were tightened daily to increase the skin available for a peninsular thoracodorsal axial pattern flap, which was created and rotated 180° to cover an antebrachial defect to a level 2 cm proximal to the carpus. Results: The entire flap survived; there was a small amount of incisional separation at the distal margin of the flap that healed without further treatment. Conclusion: Preoperative skin stretching provided additional skin for the axial pattern flap used. 相似文献
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