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91.
Earthwork operations accounted for great amount of forest road construction costs. Any Optimization in planning road profile needs a reliable objective function that calculates earthwork volume in an appropriate time and accuracy. This study aimed at incorporating the shape of the ground cross sections in calculating cut/fill areas using three alternative methods including: Multiple Linear Regression (MLR), Artificial Neural Network (ANN) and heuristic programming in MATLAB environment. The accuracy of results was validated via AutoCAD as a manual method for area calculation of road’s cross-section. Trapezoidal method applied to calculate the area of cut/fill in the heuristic method. Paired sample T-Test and statistical analysis (ANOVA) with confidence level of 0.95 indicated that the heuristic method not only reduced computing time but also provided accurate estimations as same as the manual AutoCAD based method. It can be concluded that although MLR and ANN estimations were as well as AutoCAD results within a reasonable time, they need to be retrained by adding, removing or changing entrance parameters.  相似文献   
92.
A crude ginseng extract (GS) and the purified ginsenoside R(b1) (R(b1)) were evaluated for their adjuvant effects in dairy cattle at immunisation with ovalbumin (OVA) and/or a Staphylococcus aureus bacterin used for prevention of bovine mastitis. To evaluate a suitable dose of GS as an adjuvant, 36 lactating cows were randomly divided into six groups. The cows were inoculated twice intramuscularly with a 2-week interval, with saline solution, OVA in saline, or OVA in combination with 4, 16 or 64 mg GS, or Al(OH)(3). The level of specific antibodies to OVA in serum and milk whey was measured before immunisations and 1-5 weeks after the second immunisation. The antibody response in serum was significantly higher in animals immunised with OVA and GS than in animals immunised with OVA alone. A significant increase in milk antibody titres compared with OVA only was only found 2 weeks after the second immunisation in the group immunised with OVA and 4 mg GS. In the second part of the study, 18 heifers were randomly divided into three groups and were immunised twice intramuscularly with a two week interval, with the S. aureus bacterin (control), or with the bacterin in combination with 4 mg GS or 1mg R(b1). The specific antibody response to S. aureus and the lymphocyte proliferation after stimulation with PWM, concanavalin A (Con A) or a specific S. aureus antigen was evaluated in blood samples taken before and after immunisations as specified above. Addition of R(b1) resulted both in significantly higher antibody production and lymphocyte proliferation in response to PWM, Con A and S. aureus antigens than in the control group. Addition of GS induced a significantly higher lymphocyte proliferation in response to PWM and Con A than the control, but had no additional effect on the antibody production. In conclusion, both GS and R(b1) were safe adjuvants, and R(b1) had the strongest adjuvant effects, when used for immunisation against S. aureus in dairy cattle. Field trials are warranted to test the ability of GS and R(b1) to enhance the efficacy of mastitis vaccines in protection against intramammary infections.  相似文献   
93.
At least two age-dependent proteins were detected in nasal secretion (NS) of young calves by crossed immunoelectrophoresis. One of them was identified as fetuin. The other one was not identified. The concentration of fetuin in NS was found to increase in cases where a sample of NS had been obtained at birth and a second sample taken within 11 days. Thereafter a decrease was always found towards day 15 or 30.  相似文献   
94.
95.
A cross-sectional study was conducted to determinate the seroprevalence rate of equine brucellosis in the state of Tamaulipas, Mexico. Serum samples from 420 equines were analyzed with the Rose Bengal test at cell concentrations of 3% (RBT-3%) and 8% (RBT-8%), and positive results were confirmed with the Rivanol test (RT). Risk factors were determined with the prevalence ratio (PR) and the use of variables generated from a questionnaire administered to the animals' owners. Serum from 1 stallion had positive results with both the RBT-8% and the RT, for a seroprevalence rate of 0.238%. Drinking of water from a pond that was also used by cattle and dogs was the only associated risk factor for this animal (PR = 0.25). However, the results were considered false-positive, because the results for other horses in the same environmental conditions were negative. Although brucellosis is considered endemic in ruminants in the study area, the results obtained suggest that equines are not a reservoir of brucellosis and do not play an important role in the epidemiologic patterns of this disease in northeastern Mexico.  相似文献   
96.

We evaluated the impact of a combined vitamin E (vit E), a mixture of nucleotide (mixed-NT), Haematococcus pluvialis (H. pluvialis), arachidonic acid (AA), and yeast extract powder (YEP) supplementations on the relative mRNA expression of reproduction and antioxidant-related genes in red claw crayfish Cherax quadricarinatus using an orthogonal design (L16 45) plus control diet for 70 days feeding trial. Five factors with four levels: A, vit E 40, 160, 240, and 320 mg/kg diet; B, mixed-NT 2, 4, 6, and 8 g/kg diet; C, H. pluvialis 2, 4, 6, and 8 g/kg diet; D, AA 5, 10, 15, and 20 g/kg diet; E, YEP 2.5, 5, 10, and 15 g/kg diet were studied. The relative mRNA expression of reproduction-related genes (vitellogenin (vtg) and fatty acid-binding protein (fabp)), and antioxidant-related genes (heat shock protein 70 (hsp70), glutathione peroxidase (gpx), glutathione S-transferase (gst), mitochondrial manganese superoxide dismutase (mmnsod), and ferritin) in hemocyte, hepatopancreas, and ovary tissues were measured. There was a major depression in gene expression levels throughout the experimental diet at high vit E 320 mg/kg level with other factors. Expression of antioxidant enzyme genes significantly increased in treatments of T9, T10, T11, and T12, while significantly decreasing in treatment of T13 and other treatment groups with high vit E 320 mg/kg levels with the other factors. Gene expression of vtg and fabp demonstrated similar patterns to those of antioxidant genes. These results provide evidence that combined supplementations of vit E, mixed-NT, H. pluvialis, AA, and YEP with vit E 240 mg/kg, mixed-NT 8 g/kg, H. pluvialis 4 g/kg, AA 5 g/kg, and YEP 10 g/kg may present a novel strategy for improving reproduction performance and antioxidant activities in RC-crayfish, C. quadricarinatus by the positive impact on the molecular level of reproduction and antioxidant genes.

  相似文献   
97.
98.
This research investigated the impact of semolina dough formulation (percentage of sourdough [SD] addition and presence of yeast [Y] or common wheat gluten [G]) added singly and in combination on the sensory and physicochemical profiles of fresh and stored sourdough‐started durum breads, particularly Moddizzosu type. Main distinctive features of breads were identified, and optimal amounts of SD addition in presence of either yeast or gluten were used to achieve high‐quality fresh and stored soured durum breads made with semolina and remilled semolina at a ratio of 80:20. Common features of durum breads included color parameters and crumb grain characteristics of either fresh or stored samples. Increasing SD significantly increased scores for overall acceptability. In yeasted costarted samples, a linear promotion of both aroma and taste intensity resulted from increasing amounts of SD, whereas the opposite trend was observed for unyeasted breads. Higher values for degree of acidification, specific volume, crumb cohesiveness, resilience, and springiness but lower pH, moisture content, crumb hardness, and chewiness in durum samples were achieved with increased SD. The presence of Y counteracted acidification, harmonized volume increase, hardness, cohesiveness, springiness, and resilience, minimizing the effects of the SD added. Y and G acting singly as crumb softeners when added together to soured durum breads started with SD at a dose >10% provided lower and slower crumb firming kinetics. Breads with especially slow retrogradation kinetics corresponded to yeasted started samples with or without added gluten, regardless the presence or absence of SD. In unyeasted soured breads, the dose of SD slightly decreased the rate and extent of amylopectin retrogradation, irrespective of gluten addition.  相似文献   
99.
When whole or skim milk was incubated with the cationic acrylate polymer Eudragit E100, a biphasic effect on the stability of casein micelles was observed. A precipitation phase was observed at low polymer/casein ratios. Strikingly, a solubilization phase of the aggregates was observed when the ratios of polymer/casein were increased. Purified alpha(s)-, beta-, and kappa-caseins or dephosphorylated caseins were equally precipitated and resolubilized by the cationic polymer, indicating no special selectivity for a particular protein or phosphate residue for these events. An increase in the size of the aggregates as the optimum precipitating amount of Eudragit E100 was reached suggests a crossbridging of the micelles by the polymer. The inhibition of the precipitation phase by high ionic strength indicates that electrostatic interactions play a critical role in complex formation. Furthermore, a dramatic reduction in size of the protein colloidal particles upon solubilization of the aggregates was observed by dynamic light scattering, indicating a dissociation of the micellar structure. Taken together, the results indicate that at low concentration Eudragit E100 may act as a precipitant of casein micelles, mainly by ionic interaction and at high concentration as an amphipathic agent, solubilizing casein micelles with a disruption of their internal structure.  相似文献   
100.
The effect of two sources of Se, selenized yeast (Se-Y) and sodium selenite, added to total mixed rations (TMR) fed to cows on Se milk content and distribution in milk components was studied on three farms for 6 weeks. The maximal increase in milk Se was attained with Se-Y supplemented at 0.3 microg g(-1). The effect was immediate, with an increase of 9 microg L(-1) being observed after only 5 days, and remained steady until the last sample at day 40 of Se supplementation. Se distribution in milk components was constant, 53.6, 42.6, and 9.3% in whey, casein, and fat, respectively, and was unaffected by the form of supplementation. The effect of the level of Se-Y supplementation on milk Se was studied on two farms. Increasing dietary Se-Y from 0 to 0.5 microg g(-1) elevated milk Se content from 20 to 39 microg L(-1). Se-enriched cow's milk at different levels can be produced by varying dietary Se supplementation in the form of selenized yeast.  相似文献   
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