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31.
The Development of Stain in Wounded Sitka Spruce Stems   总被引:1,自引:0,他引:1  
GREGORY  S. C. 《Forestry》1986,59(2):199-208
In order to investigate the severity of staining in woundedSitka spruce stems, the vertical extent of two categories ofstain (based on colour and termed ‘light’ and ‘heavy’)was measured in stems at two sites in south Scotland. Data wereobtained from 98 wounds most of which were between 8 and 14years old and most of which had been caused by Red deer. Theupward extent of stain and its rate of upward spread were positivelycorrelated with wound surface area and length. Most stain wasof the light type which, although it was associated with nearlyall wounds, usually constituted an insignificant defect anddid not commonly extend for more than 1 m ahve wounds. Heavystain occurred above less than half of all wounds studied butwas common above wounds exceeding 300 cm2 surface area. Forall wounds, the mean value for the upward extent of heavy stainwas 16.1 cm with a mean rate of spread of 1.9 cm y–1.However, for wounds exceeding 300 cm2 surface area, the valueswere 51.7 cm and 5.5 cm y–1. These results suggest that,although there is an important effect of wound size on the typeand extent of stain, wounds of the type studied are unlikelyto lead to severe stain and decay in Sitka spruce over a periodof 8–14 years. The results are discussed in relation toother studies on wound staining in conifers.  相似文献   
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The purpose of this paper is to construct monthly manufacturing output indexes for a metropolitan area, employing a method used by the Federal Reserve Banks to construct regional manufacturing indexes. The Tulsa metropolitan area is the region considered. The index of total manufacturing output is included in a vector autoregression model of the Tulsa economy. The results indicate that the linkages between manufacturing activity and non-manufacturing employment differ from the linkages between employment in those sectors, and that since the early 1980s both sectors have become less sensitive to changes in the price of oil.  相似文献   
34.
The medical records of five dogs diagnosed with infectious pericardial effusion were reviewed. Clinical signs included anorexia, depression, respiratory distress, abdominal distension, collapse, coughing, and vomiting. Anemia and leukocytosis were present in three dogs. Grass awn migration was confirmed as the cause of the pericardial effusion in two dogs and suspected in the other three. Surgery, followed by continuous chest drainage, and appropriate antibiotic therapy was the treatment in four dogs. Chest drains were removed within 4 days of surgery. One dog did not have chest drainage after surgery. Antibiotic treatment was continued for up to 6 months. The dogs were monitored postsurgically for a period ranging from 3 to 24 months. All dogs recovered well without apparent complications.  相似文献   
35.
The hydatid Limitation Program in Tasmania began in 1965 with the annual purging of dogs to identify areas of high prevalence of Echinococcus granulosus combined with a strong educational program aimed at preventing access to offal by dogs. From 1969 to 1975 aenia spp detected in dog purges were submitted for identification and changes in annual prevalences analysed for each species. Despite a significant reduction in the prevalence of E. granulosus since the beginning of the program, the control measures involved have apparently not predisposed to any significant change in the prevalence of T. ovis and T. hydatigena during the period of this survey.  相似文献   
36.
Surface oxygen tension (PSO2) was measured in dogs during experimental manipulation of the portal vein and hepatic artery, and during surgery to correct portosystemic shunting. There was no alteration in PSO2 of liver, pancreas, duodenum, or jejunum during partial (50%) or complete reduction of hepatic artery flow. After 100% reduction in portal vein blood flow, PSO2 was lower in jejunum, duodenum, and liver. With 50% reduction in portal flow, PSO2 was significantly decreased only in jejunum. In six dogs with single extrahepatic shunts, there was a significant correlation between portal pressure and jejunal PSO2. It was concluded that measurement of visceral organ PSO2 represents an accurate noninvasive means of obtaining objective data on the effect of reduction in hepatic blood flow on perfusion of other select splanchnic organs.  相似文献   
37.
Objective To investigate wool organophosphorus concentrations resulting from a range of farm pesticide application methods.
Design Random sampling of wool for pesticide residues and on-farm interviews to determine associated treatments.
Procedure Tasmanian fleece wool lots were sampled at random and tested for organophosphorus residues. The grower was identified and the pesticide treatments applied to the sheep were ascertained by on-farm interview.
Results The residue concentrations showed a large variation that was not accounted for by differences in treatments by growers. Organophosphorus concentrations were proportional to the number of treatments applied, and inversely related to the time between pesticide application and the subsequent shearing, and were significantly influenced by the method of application. After allowing for the time of application, plunge dipping resulted in pesticide residue concentrations 2 to 2.5 times greater than shower dipping, using spray races or hand jetting, and the use of these methods caused larger residues than the use of jetting races.
Conclusions We recommend that plunge or shower dipping should not be used more than 7 weeks after shearing, nor at higher concentration than the standard dose rate used for lice control, whereas jetting may be satisfactory for up to 7 months after shearing, provided only one application is administered.  相似文献   
38.
The purpose of this paper is to examine how regional manufacturing responds to a decline in manufacturing activity nationwide. A trivariate VAR model of the relationships between the Federal Reserve Board's Industrial Production Index for manufacturing, and two regional manufacturing output indexes is estimated. The regions considered correspond to the Fifth and the Seventh Federal Reserve Districts. A negative shock in the national index is imposed on the system to demonstrate the following: durations and general patterns of the impulse responses; severity of the responses in the two patterns; reaction times; and interregional differences in response patterns. The findings indicate that the response patterns generally differ between the regions.  相似文献   
39.
A mare with hemorrhage caused by guttural pouch mycosis was treated by insertion of a balloon-tipped catheter into the left internal carotid artery. During recovery from general anesthesia, the mare had profuse epistaxis, and was anesthetized again to determine the site of hemorrhage. The affected guttural pouch was opened to confirm that hemorrhage was from the left internal carotid artery. The mare was euthanatized, and, at necropsy, the balloon catheter was found in an aberrant branch that arose from the internal carotid artery and joined the basilar artery. The mycotic plaque was on the left internal carotid artery, distal to the origin of the aberrant branch, so that the balloon did not obstruct retrograde flow through the infected segment. Additional dissection of the internal carotid artery before insertion of a balloon catheter is recommended to identify any aberrant branches. Ligation of aberrant branches at their bifurcation with the internal carotid artery is recommended to prevent both inadvertent catheterization and retrograde flow from the cerebral arterial circle.  相似文献   
40.
Contact area and pressure between 6-hole broad dynamic compression plates and 20 pairs of equine third metatarsal bones were measured using nonluted and luted plating techniques. Pressure-sensitive film (pressure ranges 10 to 50 MPa and 50 to 130 MPa) was used as the static pressure transducer. Nonluted and one of two luting techniques were tested on each pair of bones; each luting technique was tested on 20 bones. Quantitative determinations of contact area and pressure were made using computerized image processing techniques. Mean (±SD) total contact area for nonluted plates was 18.49%± 3.5% of the potential plate-bone contact area. Luting increased ( P <.05) total contact area to 25.56%± 4.0% and 31.29%± 6.6% for the respective luting techniques. The effects of luting on contact area were dependent on the contact pressure. At contact pressure ranges 10 to 20 and 21 to 35 MPa, luting increased contact area. In contact pressure ranges 36 to 45 and 50 to 65 MPa, plate-bone contact was inherently greatest and plate luting had no significant effect on contact area. In contact pressure ranges 66 to 99 and 100 to 126 MPa, luting decreased contact area. Contact area was increased at lower contact pressures at the expense of higher pressure contact. Contact in the middle third of the plate was 20% to 40% of the contact at either end of the plate. Plate luting increased contact area best where plate-bone contour was most similar.  相似文献   
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