Heats of transfer and activation energy for bound water diffusion in wood     

Ralph M. Nelson Jr. 《Wood Science and Technology》1991,25(3):193-202

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Diffusion of bound water in wood     

R. M. Nelson Jr. 《Wood Science and Technology》1986,20(4):309-328

Summary Choong's (1963) data for isothermal sorption of water vapor by wood are used to compute pressures, chemical potentials, and entropies of water in the wood specimens of his nonisothermal mass equilibrium experiments. Entropies of both the bound water and water vapor were reasonably constant. A balance existed between thermal diffusion and mass diffusion, as indicated by gradients in temperature and chemical potential. This balance also is suggested by opposing gradients in spreading pressure and vapor pressure. Equal chemical potentials showed that the vapor and bound water were in equilibrium. The model proposed by Siau (1980) for nonisothermal diffusion is consistent with these results. Expressions are given for the two unknown parameters in this model: moisture conductivity and heat of transfer. The constant entropy of water vapor is used to show that the heat of transfer exceeds the activation energy for bound water diffusion by about 25 percent.The author wishes to thank Dr. Christen Skaar for his helpful comments during preparation of this paper for publication  相似文献   

Community Perspective on State Forest Management Regime and its Implication on Forest Sustainability: A Case Study of Chobe Forest Reserve,Botswana     

Hesekia Garekae  Joyce Lepetu  Olekae T Thakadu  Venus Sebina  Nelson Tselaesele 《Journal of Sustainable Forestry》2020,39(7):692-709

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Versatility of the Angularis Oris Axial Pattern Flap for Facial Reconstruction          下载免费PDF全文

Sara L. Losinski  Bryden J. Stanley  Sandra P. Schallberger  Laura L. Nelson  Heather A.M. Towle Millard 《Veterinary surgery : VS》2015,44(8):930-938

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Long‐Term Functional Outcome of Tibial Plateau Leveling Osteotomy Versus Extracapsular Repair in a Heterogeneous Population of Dog          下载免费PDF全文

Dirsko von Pfeil  Mike Edwards  Samantha Nelson  Ursula Krotscheck 《Veterinary surgery : VS》2015,44(7):920-920

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Clinical,histopathological and immunohistochemical characterization of a novel equine ocular disorder: heterochromic iridocyclitis with secondary keratitis in adult horses          下载免费PDF全文

Nelson I. Pinto  Richard J. McMullen Jr.  Keith E. Linder  John M. Cullen  Brian C. Gilger 《Veterinary ophthalmology》2015,18(6):443-456

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Identification of glycinin and beta-conglycinin subunits that contribute to the increased protein content of high-protein soybean lines     

Krishnan HB  Natarajan SS  Mahmoud AA  Nelson RL 《Journal of agricultural and food chemistry》2007,55(5):1839-1845

Seed protein concentration of commercial soybean cultivars calculated on a dry weight basis ranges from approximately 37 to 42% depending on genotype and location. A concerted research effort is ongoing to further increase protein concentration. Several soybean plant introductions (PI) are known to contain greater than 50% protein. These PIs are exploited by breeders to incorporate the high-protein trait into commercial North American cultivars. Currently, limited information is available on the biochemical and genetic mechanisms that regulate high-proteins. In this study, we have carried out proteomic and molecular analysis of seed proteins of LG00-13260 and its parental high-protein lines PI 427138 and BARC-6. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed that the high-protein lines accumulated increased amounts of beta-conglycinin and glycinins, when compared with Williams 82. High-resolution two-dimensional electrophoresis utilizing pH 4-7 and pH 6-11 ampholytes enabled improved resolution of soybean seed proteins. A total of 38 protein spots, representing the different subunits of beta-conglycinin and glycinin, were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. High-protein was correlated with an increase in the accumulation of most of the subunits representing beta-conglycinin and glycinin. Comparisons of the amino acid profiles of high-protein soybean lines revealed that the concentration of sulfur amino acids, a reflection of protein quality, was not influenced by the protein concentration. Southern blot analysis showed the presence of genotypic variation at the DNA level between PI 427138 and BARC-6 for the genes encoding group1 glycinin, beta-conglycinin, Bowman-Birk inhibitor (BBI), and the Kunitz trypsin inhibitor (KTI). LG00-13260 inherited the allelic variants of the parental line PI 427138 for glycinin, beta-conglycinin, and KTI, while BBI was inherited from the parental line BARC-6. The results of our study indicate that high-seed protein concentration is attributed to greater accumulation of specific components of beta-conglycinin and glycinin subunits presumably mediated by preferential expression of these genes during seed development.  相似文献   

Clinical Findings,Diagnostic Test Results,and Treatment Outcome in Cats with Spontaneous Hyperadrenocorticism: 30 Cases     

S.Y. Valentin  C.C. Cortright  R.W. Nelson  B.M. Pressler  D. Rosenberg  G.E. Moore  J.C. Scott‐Moncrieff 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):481-487

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A classification and evaluation of Irish water beetle assemblages     

Garth N. Foster  Brian H. Nelson  David T. Bilton  Derek A. Lott  Robert Merritt  Richard S. Weyl  Michael D. Eyre 《水产资源保护:海洋与淡水生态系统》1992,2(2):185-208

1. Modern records of 165 species of wetland beetle (Haliplidae, Hygrobiidae, Noteridae, Dytiscidae, Gyrinidae, Georissidae, Hydrochidae, Helophoridae, Hydrophilidae, Hydraenidae, Scirtidae, Dryopidae, Elmidae, Chrysomelidae, Curculionidae) were assembled for analysis. 2. Two hundred and eighty nine modern lists of seven or more species of water beetle from sites in Ireland were subjected to multivariate analysis. 3. Ten assemblage types were identified using TWINSPAN. Habitats typical of these assemblages are: A. deep rivers; B. rivers with riffles; C. puddles; D. canals and lakes with rich vegetation; E. ponds and ditches; F. turloughs; G. natural, minerotrophic fens; H. base-flushed cutover bogs; I. peat bogs; J. montane flushes. The distribution of these types is discussed. 4. Ordination of site data by DECORANA indicated that the important environmental variables dictating water beetle assemblage type in Ireland were: flow; water permanence; exposure; type of substratum. Acidity could not be isolated as a determinant, except within the analysis of assemblage types conducted using TWINSPAN. DECORANA isolated one brackish site as an outlier but salinity was not otherwise a major factor, probably because few brackish sites were included in the analysis. 5. The number of modern records for each species was used to provide a provisional set of species-quality scores. A simple rationale was devised to weight these scores in favour of relict species and against elusive species, species with short-lived adults and species primarily associated with man-made habitats. 6. The average species-quality score per site and the number of species recorded were used to rank sites within each TWINSPAN end-group. The most diverse sites with the highest quality were some turloughs, rich fens and base-flushed peat cutting complexes. Some montane lakes and flushes with relatively few species had high species-quality scores.  相似文献   

COMPUTED TOMOGRAPHIC IDENTIFICATION OF DYSPLASIA AND PROGRESSION OF OSTEOARTHRITIS IN DOG ELBOWS PREVIOUSLY ASSIGNED OFA GRADES 0 AND 1     

Chelsea M. Kunst  Anthony P. Pease  Nathan C. Nelson  Greg Habing  Elizabeth A. Ballegeer 《Veterinary radiology & ultrasound》2014,55(5):511-520

Elbow dysplasia is a heritable disease that is a common cause of lameness and progressive elbow osteoarthritis in young large breed dogs. The Orthopedic Foundation for Animals (OFA) screens elbow radiographs, and assigns grades 0–3 based on presence and severity of bony proliferation on the anconeal process. Grade 1 is assigned when less than 3 mm is present and considered positive for dysplasia. We investigated the incidence of elbow dysplasia and progression of osteoarthritis in elbows with grades 0 and 1 in 46 elbows screened at least 1 year previously, using CT as a gold standard and with the addition of CT absorptiometry. The incidence of dysplasia based on CT was 62% in grade 0, and 75% in grade 1 elbows, all of which had medial coronoid disease. Progressive osteoarthritis at recheck was consistent with elbow dysplasia. The sensitivity and specificity of the OFA grade for elbow dysplasia compared to CT findings was 75% and 38%, respectively. Increased bone mineral density of the medial coronoid process as characterized by osteoabsorptiometry warrants further investigation with respect to elbow dysplasia. Proliferation on the anconeal process without CT evidence of dysplasia or osteoarthritis was present in 20% of the elbows, and is theorized to be an anatomic variant or enthesopathy of the olecranon ligament/synovium. Results of our study suggest that the “anconeal bump” used for elbow screening by the OFA is a relatively insensitive characteristic, and support the use of CT for identifying additional characteristics of elbow dysplasia.  相似文献