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81.
Tropical Animal Health and Production - Campylobacter is reported as a major cause of foodborne illness worldwide. Consumption of contaminated chicken meat is considered a significant risk factor...  相似文献   
82.
In this study, we evaluated how increased cation supply can alleviate the toxic effects of NaCl on plants and how it affects essential oils (EOs) and phenolic diterpene composition in leaves of rosemary (Rosmarinus officinalis L.) plants grown in pots. Two concentrations of the chloride salts KCl, CaCl2, MgCl2, and FeCl3 were used together with 100 mM NaCl to study the effects of these nutrients on plant mineral nutrition and leaf monoterpene, phenolic diterpene, and EO composition. The addition of 100 mM NaCl, which decreased K+, Ca2+, and Mg2+ concentrations with increasing Na+ in leaves, significantly altered secondary metabolite accumulation. Addition of MgCl2 and FeCl3 altered leaf EO composition in 100 mM NaCl–treated rosemary plants while KCl and CaCl2 did not. Furthermore, addition of CaCl2 promoted the accumulation of the major phenolic diterpene, carnosic acid, in the leaves. The carnosol concentration was reduced by the addition of KCl to salt‐stressed plants. It is concluded that different salt applications in combination with NaCl treatment may have a pronounced effect on phenolic diterpene and EO composition in rosemary leaves thus indicating that ionic interactions may be carefully considered in the cultivation of these species to achieve the desired concentrations of these secondary metabolites.  相似文献   
83.
This communication describes the first record of orf infection in goats following ear-tagging. Typical orf lesions were observed in the affected goats, and the virus was reisolated and identified from them. The threat of orf infection following ear-tagging should be kept in mind in orf-endemic regions.  相似文献   
84.
Performances of an ELISA, an immunofluorescence assay (IFA) and a complement fixation test (CFT) were assessed for detecting antibodies against Coxiella burnetii after Q fever abortions in naturally infected goats. The goal of the study was to provide information useful for veterinary serodiagnosis in regard to categories of goats either experiencing Q fever abortion or not, blood sampling times and recommended cut-offs. The study was conducted on eight goat herds with evidence of C. burnetii abortions. In each herd, at least 5 goats that had aborted and 10 goats prior to parturition or at term were monitored 15, 30 and 60 days (D15, D30, D60) after the onset of Q fever abortion. The overall CFT results distribution did not differ between the two groups of goats and showed poor agreement with the ELISA results. In contrast, the ELISA and IFA results revealed comparable significant differences, but overall the ELISA test was slightly more sensitive than the IFA test. Seroprevalence, according to ELISA and IFA respectively, was higher in the aborting (88% and 82%) than in the non-aborting group (60% and 50%). High levels of serum antibodies were detected in goats post-abortion with an average of 114 %OD using ELISA and a log10(titer) of 2.4 using IFA. Strongly positive ELISA (%OD>80) and positive IFA results (log10(titers)>1.9) were significantly associated with abortion. Sampling on D15 gave the best association with ORs of 10 for ELISA and 6 for IFA. The practical interest of these results is discussed.  相似文献   
85.
Journal of Soils and Sediments - Loess in Northern Italy has been usually considered deposited during the MIS 4-2 period, which corresponds to the last Pleistocene glacial cycle. In particular, no...  相似文献   
86.
Chemical treatment is an often-followed route to improve the physical and mechanical properties of natural fiber reinforced polymer matrix composites. In this study, the effect of chemical treatment on physical and mechanical properties of jute fiber reinforced polypropylene (PP) biocomposites with different fiber loading (5, 10, 15, and 20 wt%) were investigated. Before being manufactured jute fiber/PP composite, raw jute fiber was chemically treated with succinic anhydride for the chemical reaction with cellulose hydroxyl group of fiber and to increase adhesion and compatibility to the polymer matrix. Jute fiber/PP composites were fabricated using high voltage hot compression technique. Fourier Transform Infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) tests were employed to evaluate the morphological properties of composite. Succinic anhydride underwent a chemical reaction with raw jute fiber which was confirmed through FTIR results. SEM micrographs of the fractured surface area were taken to study the fiber/matrix interface adhesion and compatibility. Reduced fiber agglomeration and improved interfacial bonding was observed under SEM in the case of treated jute fiber/PP composites. The mechanical properties of jute/PP composite in terms of Tensile strength and Young’s modulus was found to be increased with fiber loading up to 15 wt% and decreased at 20 wt%. Conversely, flexural strength and flexural modulus increased with fiber loading up to 10 wt% and start decreasing at 15 wt%. The treated jute/PP composite samples had higher hardness (Rockwell) and lower water absorption value compared to that of the untreated ones.  相似文献   
87.
The critical nitrogen (N) requirement of rice crops for maximum yields is well known. To overcome acute N deficiency in rice soils as a result of an increasing yield per unit area in the past 50 years of almost three-fold, this element has been usually supplied to the rice crop as the chemical fertilizer ‘urea’. Unfortunately a substantial amount of the urea-N is lost through different mechanisms, causing environmental pollution problems. In principle, utilization of biological nitrogen fixation technology can supplement the use of urea-N, reducing the environmental problems to a considerable extent by improving nitrogen use efficiency. Different biological nitrogen fixation (BNF) systems have different potentials to provide an N supplement. It is necessary to design appropriate strategies to obtain more sustainable N supply to the rice crop. This paper reviews research to evaluate the potential of different BNF systems to supply N for the rice crop, assessing the current information.  相似文献   
88.
The response of faba bean Vicia faba (Giza 2 variety) towards soaking conditions differed greatly since the absorbed quantities of water (either by the whole or the decorticated forms) are a function of their chemical constituents. On the other hand, 28.45% of the total vicine (vicine + convicine) present in the whole faba bean samples was extracted after soaking for 72 h at room temperature. Subsequently, other soaking mediums, i.e., 0.5% sodium carbonate and/or 1% acetic acid were used in an attempt to increase the level of vicine elimination. Percentage removal of total vicine in whole faba bean was higher in the acidic (61.31%) than the alkaline (38.40%) medium under the conditions tested, i.e., at room temperature for 72 hours. The rates of vicine + convicine elimination in decorticated faba bean for the acidic acid and alkaline soaking media were 78.46 and 79.13%, respectively. The solubility ratio of total vicine relative to soaking solutions (H2O:Na2CO3:Acetic acid) was 1:1.35:2.16 in the whole broad bean and 1:2.41:2.39 in the decorticated samples. The residual amounts of total vicine (78.33% and 77.27%) present after stewing under normal and under pressure cooking conditions could be expected to be decreased to 30.33% for the former and 29.92% for the later after 72 h of soaking. Regression analysis was used to estimate the theoretical zero point of vicine elimination from faba bean through soaking in 1% acetic acid.  相似文献   
89.
Abstract

Enhancing rice yield is a great challenge for rice growers in the tidal flooded ecosystem, where poor agronomic management is one of the major constrains. Improve management practice (IMP) was compared with traditional farmers’ practice (TFP) in evaluating rice productivity, nutrient uptake, translocation and farm income in tidal flooded ecosystem. Results revealed that, IMP significantly produced higher number of panicles m?2, more grain panicle?1 and better grain filling. The rice cultivars produced 2.0 to 2.5 t grain ha?1 with TFP, while 3.0 to 4.0 t ha?1 with IMP. In different rice cultivars, the grain yield in IMP increased 12 to 60% over TFP. Similarly, the grains in IMP treatment absorbed 21.41 to 57.03?kg N ha?1 whereas only 15.85 to 46.94?kg N ha?1 in TFP plot. However, higher nitrogen (N) transfer from shoot to grain in IMP also suggests that the amount of N in soil was too low to meet the plant demand in TFP. Although, the IMP involved additional cost, but it gave significantly higher gross return (438 to 954?US$ha?1) and margin (397 to 913?US$ha?1) which added farm income upto 225?US$ha?1 over TFP. Hence, it could be concluded that IMP is a potential option for increasing grain yield and farm income during aman season in the tidal flooded ecosystem.  相似文献   
90.
An experiment was conducted to study the response of maize to magnesium (Mg) and to find out the residual effect of Mg and green manure (GM) on transplanted aman (T. aman) rice in the maize–GM–T. aman cropping pattern. There were six treatments: T1 (recommended dose of fertilizer (RDF) + 0 kg Mg + 2 t CaCO3 ha?1), T2 (RDF + 10 kg Mg + 2 t CaCO3 ha?1), T3 (RDF + 20 kg Mg +2 t CaCO3 ha?1), T4 (RDF + 30 kg Mg + 2 t CaCO3 ha?1), T5 (RDF) and T6 (2 t CaCO3 ha?1). The response of maize to Mg was quadratic and the optimum dose of Mg was found to be 19 kg ha?1, which resulted in maximum yield of 10,507 kg ha?1. The residual effect of Mg along with GM and reduced dose of chemical fertilizer resulted in significant increase of grain yield of rice. Thus, N250P60K100Mg19S40Zn5B2 kg ha?1 for maize, only 20 kg N ha?1 for GM (Sesbania) and N60P9K33S10Zn1B1 kg ha?1 for T. aman appeared as the best combination for maximizing the productivity and may be recommended for this pattern at non-calcareous light-textured soils of Bangladesh. Application of lime increased soil pH, and this together with fertilizer and GM tended to improve soil fertility and thus may be recommended for soil amelioration.  相似文献   
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