Three-dimensional finite element analysis of the Japanese traditional post-and-beam connection     

Jung-Pyo Hong  J. David Barrett  Frank Lam 《Journal of Wood Science》2011,57(2):119-125

A three-dimensional finite solid element model for Japanese traditional post-and-beam connections was developed using the wood foundation method, which employed the concept of a beam on a nonlinear foundation. The wood foundation in the model was a three-dimensionally prescribed zone surrounding a nail shank in order to address the intricate wood crushing behavior induced by nail slip. Material models for the wood members and the foundation were developed based on the transversely isotropic plasticity from the software package ANSYS. The Japanese post-and-beam connection modeled was a ten-nail multiple connection with a mortise and tenon joint and is called the CPT (Corner Plate, T-shaped) connection. Details of the model development are presented. As a feasibility study, blind predictions of the model were compared with available connection test data and showed good results for predicting the progress of the load-deformation relations in three dimensions. However, the limitation of the model was found in simulating fracture failures such as wood splitting or nail tear-out from the wood. Model applications and the need for model improvement are discussed.  相似文献   

Modeling organic and inorganic acidity in two Nova Scotia rivers     

D. C. L. Lam  A. G. Bobba  R. A. Bourbonniere  G. D. Howell  M. E. Thompson 《Water, air, and soil pollution》1989,46(1-4):277-287

A watershed acidification model is modified to include organic acids and applied to the colored Moose Pit Brook and Mersey River in Nova Scotia. Comparison with 1983–1985 data confirmed the capability of the model to explain the different levels of organic and inorganic acidity exhibited in these two rivers. Based on the charge balance approach and a triprotic organic acid model, the charge density was found to be about 4 μeq organic anions per mg C of dissolved organic C for these two rivers.  相似文献   

The practice of leaching boron and soluble salts from fly ash-amended soils     

H. T. Phung  H. V. Lam  A. L. Page  L. J. Lund 《Water, air, and soil pollution》1979,12(2):247-254

The leachability of B and salts from two fly ash-amended soils was conducted in a column leaching experiment. Fly ash was applied to the surface 3 cm of a Baywood (acid) sand and an Arizo (calcareous) sandy, loam at 5% by weight; the columns were continously leached with Colorado River water at two different pH's. Boron from fly ash was solubilized more readily in the Baywood than in the Arizo soil. Addition of fly ash increased B levels in the leachates from 0.25 to 2.35 μg ml^?1 (Baywood) and 0.93 μg ml^?1 (Arizo). Acidified leaching water had no significant effect on B leaching patterns but resulted in leaching higher soluble salts. Approximately 348 and 161 cm of water for the Arizo and the Baywood soils respectively, would be required to reduce the B concentration below a critical limit for B sensitive crops. It is suggested that crops planted when fly ash is applied for disposal/recycling on land should be both salt and B tolerant.  相似文献   

Curative effect of topical treatment of digital dermatitis with a gel containing activated copper and zinc chelate     

Holzhauer M  Bartels CJ  van Barneveld M  Vulders C  Lam T 《The Veterinary record》2011,169(21):555

The efficacy of two topical treatments for painful ulcerative stage (M2) of bovine digital dermatitis (BDD) lesions was compared in a clinical trial conducted on five dairy farms in 2009 to 2010. The first treatment was a water-based gel with active components copper and zinc (Intra Hoof-fit gel [IHF]) and the second treatment was a topical chlortetracycline spray (CTC spray). The experimental unit for this study was the hindleg with the presence of a BDD lesion. Cure was defined as the transition of an M2 lesion into a healed (M0) or a non-painful chronic stage (M4) of BDD at D28. On day 0, cows with M2 BDD lesions were photographed and were treated with either IHF or CTC. Subsequently, feet were photographed and scored on D28. The cure rate of M2 BDD lesions treated with IHF at D28 was 0.92 (CI 0.84 to 0.96) and was significantly better than for M2 BDD lesions treated with CTC, which was 0.58 (CI 0.47 to 0.68).  相似文献   

Antimicrobial susceptibility of coagulase-negative staphylococci isolated from bovine milk samples     

Sampimon OC  Lam TJ  Mevius DJ  Schukken YH  Zadoks RN 《Veterinary microbiology》2011,150(1-2):173-179

The aim of this study was to examine whether antimicrobial resistance profiles of coagulase-negative Staphylococcus (CNS) species isolated from milk of dairy cows differed between bacterial species, and to compare results obtained by phenotypic and genotypic profiling of resistance to penicillin, oxacillin and macrolide-lincosamide (ML) antibiotics. Of 170 CNS isolates, 83 (48.8%) were phenotypically susceptible to all antimicrobial agents tested in minimum inhibitory concentration (MIC) assays, 40.6% expressed resistance to a single compound or a single class of compounds, and 10.6% to multiple drug classes. Nine percent, 68%, 19%, 4% and 1% of isolates were negative for all resistance genes tested by PCR or positive for one, two, three or four resistance genes, respectively. Phenotypic resistance and detection of resistance genes other than blaZ were relatively rare in Staphylococcus chromogenes, which was the most common CNS species (36% of 170 genotypically identified isolates). In Staphylococcus epidermidis, which was the second most common CNS species (14% of isolates), phenotypic penicillin resistance was significantly more common than in other CNS species. Almost half of the S. epidermidis isolates carried multiple resistance genes and 30% carried the methicillin resistance gene mecA. Survival analysis using MIC values showed significant associations between phenotypic and genotypic resistance profiles. We conclude that CNS species from bovine milk differ significantly in phenotypic and genotypic antimicrobial resistance profiles, which has implications for treatment and management decisions.  相似文献   

Markers of feline leukaemia virus infection or exposure in cats from a region of low seroprevalence     

Beatty JA  Tasker S  Jarrett O  Lam A  Gibson S  Noe-Nordberg A  Phillips A  Fawcett A  Barrs VR 《Journal of Feline Medicine and Surgery》2011,13(12):927-933

Molecular techniques have demonstrated that cats may harbour feline leukaemia virus (FeLV) provirus in the absence of antigenaemia. Using quantitative real-time polymerase chain reaction (qPCR), p27 enzyme-linked immunosorbent assay (ELISA), anti-feline oncornavirus-associated cell-membrane-antigen (FOCMA) antibody testing and virus isolation (VI) we investigated three groups of cats. Among cats with cytopenias or lymphoma, 2/75 were transiently positive for provirus and anti-FOCMA antibodies were the only evidence of exposure in another. In 169 young, healthy cats, all tests were negative. In contrast, 3/4 cats from a closed household where FeLV was confirmed by isolation, had evidence of infection. Our results support a role for factors other than FeLV in the pathogenesis of cytopenias and lymphoma. There was no evidence of exposure in young cats. In regions of low prevalence, where the positive predictive value of antigen testing is low, qPCR may assist with diagnosis.  相似文献   

Clinical skills and knowledge used by veterinary graduates during their first year in small animal practice     

WT CLARK  L. KANE  PK ARNOLD  ID ROBERTSON 《Australian veterinary journal》2002,80(1):37-40

Objective To determine the clinical skills and areas of knowledge used by veterinarians in small animal practice during their first year after graduation and the degree of assistance and supervision they received while developing these skills. Design A postal survey was sent in December 1999 to 59 veterinarians who completed their training at Murdoch University in December 1998. Procedure The first part of the survey asked for information on veterinary work patterns since leaving university. The second part consisted of a list of diagnostic and therapeutic skills of varying complexity and the graduates were asked to indicate whether they had used these skills in practice and whether they had been assisted or supervised while doing them. The respondents were also asked if they had had the opportunity to practise these skills as undergraduates at university or during extramural experience. In the third part the areas of knowledge used in practice were assessed by analysis of a series of consecutive cases. Results Forty replies were received but since three graduates had done no small animal work the analysis of the skills section is based on 37 responses. Thirty graduates supplied information on 994 canine cases and 308 feline cases. The distribution of the mean work time was dogs and cats 69%, horses 13%, farm animals 11%, birds 3% and others 4%. Skills used by over 90% of graduates included general anaesthesia, examination of the tympanic membrane, taking and interpreting an abdominal radiograph, catheterising a male cat, fine needle aspiration of a mass, neutering dogs and cats, tooth scaling and extraction and treating an aural haematoma. The survey also identified the opportunities for undergraduates to practise some of these skills during extramural experience and the extent of assistance given to new graduates during their first year in practice. The areas of knowledge used in over 10% of the cases included vaccination, anaesthesia/sedation, skin/coat problems, general advice on pet health, neutering and musculoskeletal diseases. Conclusion Veterinarians, in their first year after graduation, use a wide range of complex diagnostic and therapeutic skills. Although many of these skills are acquired during the undergraduate training, a significant contribution is made by extramural practical work undertaken during the clinical years of the undergraduate course and in the first year following graduation. Practising veterinarians play an important role in providing opportunities and supervision for clinical training.  相似文献   

A national serological survey to verify Australia's freedom from porcine reproductive and respiratory syndrome   总被引：4，自引：0，他引：4  

MG GARNER  LJ GLEESON  PK HOLYOAKE  RM CANNON  WJ DOUGHTY 《Australian veterinary journal》1997,75(8):596-600

Objective To provide serological data to support Australia's claim of freedom from porcine reproductive and respiratory syndrome.
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus.  相似文献   

Mycoplasmal pneumonia of swine: serologic response in pigs   总被引：1，自引：0，他引：1  

K M Lam  W P Switzer 《American journal of veterinary research》1972,33(7):1329-1332

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COMPUTED TOMOGRAPHIC FINDINGS IN 15 DOGS WITH EOSINOPHILIC BRONCHOPNEUMOPATHY          下载免费PDF全文

Luis Mesquita  Richard Lam  Christopher R. Lamb  J. Fraser McConnell 《Veterinary radiology & ultrasound》2015,56(1):33-39

Eosinophilic bronchopneumopathy is a disease characterized by the infiltration of the lung and bronchial mucosa by eosinophils. The aim of the present study was to describe the CT findings in a large series of dogs with confirmed diagnosis of eosinophilic bronchopneumopathy. Computed tomographic scans of 15 dogs with confirmed diagnosis of eosinophilic bronchopneumopathy were evaluated retrospectively by two boarded radiologists who reached a consensus. Abnormalities were identified in 14/15 (93%) dogs, including pulmonary parenchymal abnormalities in 14/15 (93%) dogs, bronchial wall thickening in 13 (87%) dogs, which was considered marked in eight (53%), plugging of the bronchial lumen by mucus/debris in 11 (73%) dogs, and bronchiectasis in nine (60%) dogs. Pulmonary nodules were identified in 5/15 (33%) dogs including one dog with a mass. All dogs with a nodular lung pattern had additional abnormalities. Lymphadenopathy was present in 10 dogs (67%). Lesions associated with eosinophilic bronchopneumopathy are variable and heterogeneous and encompass a wider variety of computed tomographic features than reported previously. Computed tomographic images were abnormal in the majority of affected dogs, hence CT is a useful modality to characterize the nature and distribution of thoracic lesions in dogs with eosinophilic bronchopneumopathy.  相似文献