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71.
This work develops a system dynamic simulation model for free-water surface constructed wetlands, as well as provides appropriate values for the parameters of constructed wetland management. The system dynamic model is calibrated and validated by using data from a 1-year study of a constructed wetland in Tainan of southern Taiwan. Additionally, the major parameters that affect the simulation output are obtained via sensitivity analysis by using generalized likelihood uncertainty estimation (GLUE). A high R 2 and Nash?CSutcliffe coefficient of efficiency between the simulated and measured outflow values indicate that in addition to reproducing the changing trends of dissolved oxygen (DO), 5-day biological oxygen demand (BOD5), total nitrogen (TN), total suspended sediment (TSS), and total phosphorous (TP) concentrations, the model can simulate the variations of DO, BOD5, and TSS. Taken into account the interactions among parameters, the GLUE method successfully obtained the model sensitive parameters from the Monte Carlo parameter sets. Sensitivity analysis results indicate that the parameters of microorganisms are sensitive factors that affect DO, BOD5, and TN, while sediment diameter largely influences TP and TSS. Further elucidating environmental microorganisms would increase the model accuracy and provide a valuable reference for constructed wetland management and design.  相似文献   
72.
Organic farming (OF) has significantly increased in importance in recent decades. Disease management in OF is largely based on the maintenance of biological diversity and soil health by balanced crop rotations, including nitrogen‐fixing and cover crops, intercrops, additions of manure and compost and reductions in soil tillage. Most soil‐borne diseases are naturally suppressed, while foliar diseases can sometimes be problematic. Only when a severe disease outbreak is expected are pesticides used that are approved for OF. A detailed overview is given of cultural and biological control measures. Attention is also given to regulated pesticides. We conclude that a systems approach to disease management is required, and that interdisciplinary research is needed to solve lingering disease problems, especially for OF in the tropics. Some of the organic regulations are in need of revision in close collaboration with various stakeholders. © 2015 Society of Chemical Industry  相似文献   
73.
1. The study focused on antioxidant molecular targets of wheat bran fermented by white rot fungi (WRF) in poultry. After solid-state fermentation of wheat bran by WRF for 12 d, scanning electron microscopy found that the lignocellulose structure showed degradation and fragmentation.

2. A total of 300 1-d-old broilers were evenly divided by gender and randomly allocated into the following treatments: (1) maize–soybean meal (control group), (2) 10% of wheat bran replacing maize (10% WB group) or (3) 10% of fermented wheat bran replacing maize (10% FWB group).

3. The results indicated that the antioxidant gene expression, such as haem oxygenase-1 and glutathione-S-transferase of chicken peripheral blood mononuclear cells, of the 10% FWB group was significantly higher than that of the control group at d 35. For genes of Nicotinamide adenine dinucleotide phosphate oxygenase 1 and reactive oxygen species modulator protein 1, the expression of the 10% FWB group was lower than that of the control group at d 21 and 35.

4. In conclusion, wheat bran fermented by WRF could increase lignocellulolytic enzyme activities and the levels of active components that further regulate the expression of antioxidant molecular targets in poultry.  相似文献   

74.
Summary The anaesthetic effects of intravenous tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg (TK) and tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg-xylazine 0.11 mg/kg (TKX) were evaluated in six wethers. Heart rate, respiration rate, arterial blood pressure, and the electrocardiogram were monitored during anaesthesia. Analgesia was tested by electrical stimulation in the left flank. Atropine (0.03 mg/kg) was given intramuscularly before induction, but after recording of baseline heart rate and respiratory rate. The duration of analgesia was 28.7 ± 6.9 min with TK and 82.8 ± 26.6 min with TKX. Heart rate increased significantly within 5 min after TK or TKX administration. Respiratory rate remained unchanged after TK administration, but increased significantly from 5 to 45 min after TKX administration. Arterial blood pressure decreased significantly at 15 min with TK and 30 min with TKX. Sheep remained recumbent for 201 min with TK and 166 min with TKX. All recovered uneventfully. We conclude that either TK or TKX may be used for anaesthetising sheep.  相似文献   
75.
This study investigates the species of Cu and As (enargite) residues present in soils of the Chinkuashih area, northern Taiwan. Two pedons, on the shoulder and footslope along a toposequence, were examined for their metal partitioning and geochemical origins. The bulk soils were analyzed by sequential extraction combined with mineralogical analyses, including X-ray diffraction (XRD) and scanning electron microscopy ∕ energy dispersive spectrometer (SEM ∕ EDS) analyses. Soil pH ranged from 4.23 to 4.91 with low base saturation, and the soils can be classified as fine, mixed, thermic, Typic Kandiudults. Mineralogical study indicated that enargite and pyrite particles mainly coexisted in silt and sand fractions, particularly in lower soil horizons of the footslope, showing high contents of Cu and As. Kaolinite and illite were dominant minerals in clay fractions. The footslope accumulated more total Cu and As than that of shoulder pedon. The sequential extraction experiments resulted in high proportions of Cu remaining in residual fractions, while the most of As was bound in amorphous Fe and Al oxyhydroxide fraction. The risk analyses of Cu and As (enargite) contamination in soils of the Chinkuashih area merits further study.  相似文献   
76.
The selection and assembly of materials are central issues in the development of smaller, more flexible batteries. Cobalt oxide has shown excellent electrochemical cycling properties and is thus under consideration as an electrode for advanced lithium batteries. We used viruses to synthesize and assemble nanowires of cobalt oxide at room temperature. By incorporating gold-binding peptides into the filament coat, we formed hybrid gold-cobalt oxide wires that improved battery capacity. Combining virus-templated synthesis at the peptide level and methods for controlling two-dimensional assembly of viruses on polyelectrolyte multilayers provides a systematic platform for integrating these nanomaterials to form thin, flexible lithium ion batteries.  相似文献   
77.
SUMMARY: The distribution and movement of the hairtail Trichiurus lepturus stock in the Aru Sea were investigated using logbook data from four Taiwanese commercial otter trawlers. Fluctuations in population size, population density index and the distribution of catch per unit effort (CPUE) and fishing effort are discussed. The CPUE data were standardized by using the generalized linear model (GLM) in which fishing month, fishing area and size category of the hairtail were taken into account. The fishing season could be divided into three episodes: aggregation between March and April, dispersion between May and June, and aggregation again between July and December. A seasonal two-peak distribution of the population size of hairtail reflects the aggregation–dispersion pattern. The first peak in May–June can be explained in terms of the hairtails' overwintering migration. The second peak in October–December is likely to be the result of spawning aggregation.  相似文献   
78.
79.
M. S. Chiang  W. K. Nip 《Euphytica》1973,22(2):393-398
Summary Leaf and root tissues of clubroot-resistant cabbage line 8–41 and cultivar Badger Shipper, and clubroot-susceptible cultivars Penn State Ballhead and Golden Acre were analysed for free amino acid content. There was no relationship between total free amino acid content and susceptibility to the disease. Alanine and asparagine contents were higher in the leaf tissue in resistant cabbage. Tyrosine content appeared to be higher in the root tissue of the resistant plants than that of susceptible ones.  相似文献   
80.
Summary Interspecific hybridization between Brassica napus L. (2n=38, a1a1c1c1) and B. oleracea var. capitata L. (2x- and 4x-cabbage; 2n=2x=18, cc and 2n=4x=36, cccc) was carried out for the purpose of transferring clubroot disease resistance from the amphidiploid species to cabbage. Nineteen hybrids with three different chromosome levels (2n=28, a1c1c; 2n=37, a1c1cc and 2n=55, a1c1cccc) were obtained. The F1 plants were mostly intermediate between the two parents but as the number of c genomes in the hybrids increased, the more closely the hybrids resembled the cabbage parent. All F1 hybrids were resistant when tested against race 2 of Plasmodiophora brassicae wor. The complete dominance of resistance over susceptibility suggested that the gene(s) controlling resistance to this particular race of the clubroot pathogen is probably located on a chromosome of the a genome in Brassica.Contribution No. J654.  相似文献   
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