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41.
The article presents a material-geographic study of contemporary log home manufacturing in the Eastern Woodlands of North America. The study investigated relationships between log conversion (i.e., processing) methods and regional location. Manufacturers were grouped by their conversion methods, using hierarchical cluster analysis; and analyzed for spatial correlation, using standard deviational ellipses (SDEs). Tree species utilization, log treatment, horizontal surface type, and corner notch type were found to be spatially differentiating. These attributes were tested for their ability to predict manufacturers’ culture region using multinomial logistic regression (MLR) models. Tree species utilization was an independent variable in all of the predictive models, suggesting a correspondence between building culture and ecological regions. This is consistent with earlier research. The findings suggest that location drives tree species utilization and, thereby, building methods. Like the eco-region itself, log conversion methods vary on a north-south gradient. It is argued that construction knowledge is geo-contextual and that the replacement of scientific wood extraction with ecosystem management as the central paradigm in forestry calls for geo-contextual approaches to sustainability in the construction industry.  相似文献   
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Objective To determine the long‐term efficacy, complications, and duration of effect of a cyclosporine (CsA) suprachoroidal implant (CSI) in horses with equine recurrent uveitis (ERU). Methods Horses with ERU were treated with a 6‐mm diameter, 25 mg, reservoir matrix CsA implant in the deep sclera adjacent to the suprachoroidal space. Horses with follow‐up >1 year were examined for frequency of uveitis episodes, complications, and vision at last recheck. Results Data from 151 eyes of 133 horses from the USA and Europe that had CsA devices implanted for ERU were reviewed. Follow‐up time ranged from 13 to 85 months after surgery, with a mean and median follow‐up time of 28.9 and 26.3 months, respectively. Overall, at last follow‐up 78.8% of eyes were considered visual and the overall mean frequency of uveitis episodes after CSI was 0.09 ± SD 0.08 episodes per month. The most common complications leading to vision loss at last follow‐up were persistent uveitis episodes (54%), glaucoma (22%), mature cataracts (16%), and retinal detachment (6%). Persistent uveitis episodes tended to be the highest cause of vision loss in horses with <24 months and >48 months of follow‐up. Conclusions This study demonstrated the long‐term maintenance of vision of horses with ERU implanted with a CSI. The increased vision loss related to uveitis episode of inflammation in eyes after the likely depletion of CsA from the CSI suggests that a repeat CSI may be required at or before 48 months after surgery.  相似文献   
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Visceral leishmaniasis was diagnosed in a 5-year-old English Foxhound born and housed in an Ohio research colony. Physical examination revealed pyrexia, hematochezia, panuveitis, splenomegaly, and lymphadenopathy. Hematologic and serum biochemical abnormalities consisted of anemia, thrombocytopenia, hypoalbuminemia, hyperglobulinemia, azotemia, and proteinuria. Postmortem examination revealed widely disseminated (spleen, bone marrow, lymph node, liver, kidney, lungs) Leishmania amastigotes within macrophages.  相似文献   
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Ischemic optic neuropathy accompanied by blindness was induced in 2 horses after surgical occlusion of the external and internal carotid and greater palatine arteries, performed as part of the management of guttural pouch mycosis. The blindness was acute and unilateral and may have been caused by ischemic retinal damage. Vascular occlusion is a recommended procedure for treatment of guttural pouch mycosis. Retinal damage and blindness are a possible complication if all possible sources of hemorrhage are occluded.  相似文献   
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Fourteen animals died or were euthanized after toxic levels of elemental sulfur were accidentally fed to a group of 120 Holstein heifers. Dehydration, rumen stasis, tachycardia, and diarrhea were seen along with metabolic acidosis, hypokalemia, and hypochloremia. The majority of deaths occurred from 3 to 10 days after the sulfur was fed to the heifers. Postmortem examination showed rumenitis, acute alveolitis, and renal tubular necrosis. The toxicity of ingested sulfur was attributed to the conversion of sulfur to hydrogen sulfide in the rumen.  相似文献   
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From 1982 to 1989, inclusive, 20 poisonings were investigated by the Ontario Ministry of Agriculture and Food following ingestion by domestic livestock of granular insecticides including terbufos (13 poisonings), disulfoton (two poisonings), fonofos (two poisonings), phorate (two poisonings), and carbofuran (one poisoning); all are used for rootworm (Diabrotica spp.) control in corn. A further three poisonings of livestock occurred following the ingestion of the foliar insecticide, endosulfan (two poisonings), and the seed protectant insecticides diazinon plus lindane (one poisoning). There were six poisoning cases as a result of excessive topical applications of the three insecticides coumpahos, fenthion, and lindane as dusts or sprays to control external parasites. Together, these events caused the deaths of 258 domestic animals of which 200 were cattle, 23 were swine, and 35 were sheep. Not all deaths are reported to the Ministry and the cases reported here may only represent 30-50% of the actual deaths over the period. Based on total populations of livestock, the percent losses were very small but they represent serious losses to individual growers. The economic loss is estimated at $160,000 over the eight years, or $20,000 per annum, and this does not include veterinary costs.

Some of the poisoned animals died within as little as three to four hours of ingestion while others were sick but survived for several days. Lethal doses of insecticide were found in the rumen, abomasum, or stomach of dead animals. Signs typical of cholinesterase inhibition caused by organophosphorus poisoning were observed in most cases. Cholinesterase readings were found to be zero in dying animals. Necropsy findings were rarely more than pulmonary edema or myocardial hemorrhage. Where organochlorine insecticides were ingested, convulsions were the major manifestation.

Contamination of feed was most often accidental, and chemical analysis was most helpful in identifying both potent and minor sources, thus facilitating cleanup procedures.

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