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31.
Evaluation of DRAINMOD using saturated hydraulic conductivity estimated by a pedotransfer function model 总被引:1,自引:0,他引:1
Direct measurement of soil saturated hydraulic conductivity (Ks) is time-consuming and therefore costly. The ROSETTA pedotransfer function model is able to estimate Ks from soil textural data, bulk density and one or two water retention points. This study evaluated the feasibility of running the DRAINMOD field-scale hydrological model with Ks input produced using ROSETTA. A hierarchical approach was adopted to estimate Ks using ROSETTA, with four limited-more extended sets of soil information used as inputs: USDA textural class (H1); texture (H2); texture and bulk density (H3); texture, bulk density, water retention at −33 kPa (θ33 kPa) and −1500 kPa (θ1500 kPa) (H4). ROSETTA-estimated Ks values from these four groups (H1-H4) were used in DRAINMOD to simulate drain outflows during a 4-year period from a conventional drainage plot (CD) and two controlled drainage plots (CWT1 and CWT2) located in south-east Sweden. The DRAINMOD results using ROSETTA-estimated Ks values were compared with observed values and with model results using laboratory-measured Ks values (H0). Deviations in simulated drainage outflow (D), infiltration (F) and evapotranspiration (ET) resulting from the use of ROSETTA-estimated rather than laboratory-measured Ks values were evaluated. During the study period, statistical comparisons showed good agreement on a monthly basis between observed and DRAINMOD-simulated drainage rates using five soil datasets (H0, H1, H2, H3 and H4). The monthly mean absolute error (MAE) ranged from 0.57 to 0.82 cm for CD, 0.38 to 0.41 cm for CWT1, and 0.15 to 0.22 cm for CWT2. On a monthly basis, the modified coefficient efficiency (E′) values were in the range of 0.62 to 0.74 for CD, 0.72 to 0.74 for CWT1, and 0.79 to 0.86 for CWT2. The modified index of agreement (d′) for monthly predictions ranged from 0.80 to 0.86 cm for CD, 0.87 to 0.88 cm for CWT1, and 0.89 to 0.93 cm for CWT2. The absolute values of the percent-normalised error (NE) on an overall basis when using ROSETTA-estimated rather than laboratory-measured Ks values were less than 3% in E, less than 1% in F, and less than 15% in D. The results suggest that ROSETTA-estimated Ks values can be used in DRAINMOD to simulate drainage outflows as accurately as laboratory-measured Ks values (H0) in coarse-textured soils. 相似文献
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Prothrombin time and activated partial thromboplastin time using a point‐of‐care analyser (Abaxis VSpro®) in Bennett's wallabies (Macropus rufogriseus) 下载免费PDF全文
BN Nevitt SK Chinnadurai MK Watson JN Langan MJ Adkesson 《Australian veterinary journal》2016,94(10):384-386
There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point‐of‐care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range. 相似文献
34.
Luis Felipe Falla Zuñiga Yhoiss Smiht Muñoz Cerón Liliana Salazar 《Anatomia, histologia, embryologia》2021,50(1):206-211
Alterations in heart valve development represent more than 20% of congenital cardiovascular malformations. Most of the functional properties of heart valves depend on extracellular matrix. Despite its relevance, little is known about fibrillar components on developing stages. Our objective is to define histological changes on valves fibrillar components in late embryonic development of Mus musculus. We found type III collagen as the predominant fibre type in the ECM in prenatal stages followed by a switch to a type I predominance for postnatal ages. The change in fibrillar components is necessary to support the normal mechanical function of adult heart valves. 相似文献
35.
Outcome of equids with clinical signs of West Nile virus infection and factors associated with death
Salazar P Traub-Dargatz JL Morley PS Wilmot DD Steffen DJ Cunningham WE Salman MD 《Journal of the American Veterinary Medical Association》2004,225(2):267-274
OBJECTIVE: To determine outcome of equids in the western United States with clinical signs of West Nile virus (WNV) infection and identify factors associated with risk of death in infected equids. DESIGN: Cross-sectional study. ANIMALS: 484 equids in Nebraska and Colorado. PROCEDURE: Owners of 484 equids with laboratory-confirmed West Nile virus infection in Nebraska and Colorado were contacted by telephone, and a questionnaire was used to obtain information on signalment, management, clinical signs, date of disease onset, duration of disease, WNV vaccination status, and health status at the time of the interview. RESULTS: 137 of 482 (28.4%) animals died or were euthanatized. Ataxia, lethargy, muscle fasciculations, and weakness were the most common clinical signs of disease. Animals > or = 3 years old were more likely to die than were animals < or = 2 years old. Unvaccinated equids were twice as likely to die as were animals that had been vaccinated at least once prior to the onset of disease. Animals that were recumbent and unable to rise were 78 times as likely to die as were animals that never lost the ability to rise. Females were 2.9 times as likely to die as males. Two hundred seventy-one of 339 (79.9%) animals that survived recovered fully; mean duration of disease for these animals was 22.3 days. CONCLUSIONS AND CLINICAL RELEVANCE: Among equids with WNV infection, age, vaccination status, an inability to rise, and sex were associated with the risk of death. 相似文献
36.
Larrasa J Garcia A Ambrose NC Alonso JM Parra A de Mendoza MH Salazar J Rey J de Mendoza JH 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(3):135-141
Dermatophilus congolensis is the pathogenic actinomycete that causes dermatophilosis in cattle, lumpy wool in sheep and rain scald in horses. Phenotypic variation between isolates has previously been described, but its genetic basis, extent and importance have not been investigated. Standard DNA extraction methods are not always successful for D. congolensis due to its complex life cycle, one stage of which is encapsulated. Here we describe the development of rapid and reliable DNA extraction and random amplified polymorphic DNA (RAPD) methods that can be used for genotyping D. congolensis field isolates. Our results suggest that genotypic variation between isolates correlates with host species. Several DNA extraction methods and RAPD protocols were compared. An extraction method based on incubation of the bacterium in lysozyme, sodium dodecyl sulphate (SDS) and proteinase K treatments and phenolic extraction yielded high-quality DNA, which was used to optimize RAPD-polymerase chain reaction (PCR) protocols for two random primers. An alternative rapid, non-phenolic extraction method based on proteinase K treatment and thermal shock was selected for routine RAPD typing of isolates. DNA extracted from reference strains from cattle, sheep and horse using either method gave reproducible banding patterns with different DNA batches and different thermal cyclers. The rapid DNA extraction method and RAPD-PCR were applied to 38 D. congolensis field isolates. The band patterns of the field and type isolates correlated with host species but not with geographical location. 相似文献
37.
Mahecha L Angulo J Salazar B Cerón M Gallo J Molina CH Molina EJ Suárez JF Lopera JJ Olivera M 《Tropical animal health and production》2008,40(3):209-216
This study was conducted to evaluate if supplementing bypass fat to cows under silvopastoral systems, increases the concentration
of unsaturated fatty acids in milk, thus improving the saturated/unsaturated ratio without a negative effect on total milk
yield in fat or protein. Two concentrations of two different sources of bypass fat were evaluated for 40 days, each in a group
of 24 multiparous Lucerna (Colombian breed) cows. A cross-over design of 8 Latin squares 3 × 3.was used The variables submitted
to analysis were body condition, daily milk production and milk composition. Body condition, milk yield and milk quality were
not different but there was a significant decrease in the amount of saturated fatty acid in both experiments while the unsaturated
fat increased significantly in experiment 1 and remained stable in experiment 2. Results, such as these have as far as we
know, not been reported previously and they provide an approach for the improvement of milk as a “functional food”. 相似文献
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Céspedes CL Lemus A Salazar JR Cabrera A Sharma P 《Journal of agricultural and food chemistry》2003,51(10):2923-2929
This work presents the herbicidal and plant growth regulatory activities of tertiary bismuthines containing heterocyclic aromatic rings of the general formula (2-C(4)H(3)X)(3)Bi, where X = S (3), O (1), or NMe (2). Toxicity against Artemia salina and herbicidal activity on Lactuca sativa, Trifolium pratense, and Lolium multiflorum were tested. In addition to the effects on mitochondrial respiration obtained from roots of Phaseolus vulgaris, these compounds also demonstrated partial radical scavenging properties against 2,2-diphenyl-1-picrylhydrazyl (DPPH). The furyl substituent is the most important structural requirement for the activity measurements observed in this study. 相似文献