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281.
This study was conducted to analyze the factors that negatively influence Pakistani farmers’ willingness to participate in crop insurance. Probit model was applied to identify the significant factors which influenced our dependent variable "not willing to participate". The results of the analyses showed that crop insurance premium was the most influencing factor which had positive and significant impact on dependent variable. Similarly dissatisfaction with crop loan insurance scheme, lacking of knowledge about crop insurance, believing of being against Islamic rules and time taking process was also found to be positive and significantly influenced the dependent variable. While limited decision power and limited perils were not found to be significant in the results.  相似文献   
282.
This study has been conducted in three districts of Punjab Province namely, Dera Ghazi Khan, RajanPur and Bahawalpur of Pakistan. The study showed the results of a survey of 300 farmers which was organ...  相似文献   
283.
Eryngium bornmuelleri Nab. (Tusî) is an endemic botanical from the Eastern Anatolia region of Turkey traditionally used for preparation of herbal tea. Within this study, phenolic composition, antioxidant capacities and inhibitory activities towards selected digestive enzymes of E. bornmuelleri leaf were investigated. Sequential extracts, obtained by extraction of plant tissue by ethanol, acetone and water exhibited pronounced antioxidant capacities and in a dose-dependent manner suppressed the metabolic syndrome related enzymes: α-amylase, α-glucosidase and pancreatic lipase. All extracts contained high levels of phenolic compounds. Flavonoid glycosides were the main phytochemicals detected, with rutin as the major compound (70 % of total phenolics). Chlorogenic, hydroxybenzoic and caftaric acids as well as traces of caffeic, ferulic and rosmarinic acids were also detected. Correlation analysis indicated that phenolic compounds were the major sources of the enzyme-inhibitory activities. This study suggests that E. bornmuelleri leaf extracts can modulate the metabolism of sugars and fats through inhibition of the relevant digestive enzymes.  相似文献   
284.
This paper presents an investigation of the influences causing failure in the materials comprising polymer matrix composites. Structures with differences in stacking sequences and design configuration are analysed. The objective of this study is to investigate and evaluate the reasons for the failure of composite lamination structures in terms of stress, strength, strain, and Young modulus within a morphology observation of composite materials. The materials selected for the study were a chopped strand mat (CSM) and a woven roving (WR) fabric. These materials are used as reinforcement and are produced by the hand lay-up technique using epoxy and polyester matrix resin. The experiment was performed using specimens made of notched (open-hole; OH) tension and un-notched (UN) shapes. The characteristics of different shapes, materials, and lamination structures are studied in this research. The results showed the failure phenomenon in the structure of the polymer matrix composite is dependent on the characteristics of the material used and the design configuration of both structures.  相似文献   
285.
This study was designed to investigate the effects of restrictive and cyclical feeding on the growth parameters of dolphin cichlid (Cyrtocara moorii Boulenger, 1902). In the study, 300 dolphin cichlid with an initial average weight of 1.12 ± 0.23 g were placed in 15 aquariums (each of them were 60 L). The five experimental groups, were designed as; the control group (A), feeding until satiation twice a day for 90 days, starvation for 1 week (B), starvation for 2 weeks (C), starvation for 1 day/satiation for 3 days (D), starvation for 1 day/satiation for 1 day (E); and the study was carried out in three repetitions. At the end of the study, groups B, C and D showed partial compensatory growth. The highest weight gains and specific growth rates were observed in control group (A), followed by groups B, C and D (p > 0.05). The lowest weight gain was observed in group E (p < 0.05). The feed conversion ratio did not show any significant difference between the groups (p > 0.05). In terms of feed consumption ratio, Control, C and D groups consumed similar amounts of feed (p > 0.05), while B and E groups consumed less feed (p < 0.05) than the other groups.  相似文献   
286.
Microalgae might be considered as an alternative source of fat and/or protein for ruminant's diets. However, changes in populations of ruminal micro‐organisms associated with biohydrogenation process, methane and ammonia production in response to microalgae dietary supplementation have not been well characterized. Thus, 16 cross‐bred goats were divided into two groups. Each goat of both groups was fed individually with alfalfa hay and concentrates separately. The concentrates of the control group had no microalgae while those of the treated group were supplemented with 10 g lyophilized Chlorella vulgaris/kg concentrate (chlor). On the 30th experimental day, samples of rumen fluid were collected for microbial DNA extraction, fatty acid profile and enzyme activity analyses. The results showed that the chlor diet compared with the control increased significantly the populations of Methanosphaera stadtmanae, Methanobrevibacter ruminantium and Methanogens bacteria and protozoa in the rumen of goats. A significant reduction in the cellulase activity and in the abundance of Ruminococcus albus, and a significant increase in the protease activity and in the abundance of Clostridium sticklandii in the rumen liquid of goats fed with the chlor diet, compared with the control, were found. Chlorella vulgaris supplementation promoted the formation of trans C18:1, trans‐11 C18:1 and monounsaturated fatty acids (MUFA), while the proportions of C18:0 and long‐chain fatty acids (LCFA) reduced significantly in the rumen liquid of goats. This shift in ruminal biohydrogenation pathway was accompanied by a significant increase in Butyrivibrio fibrisolvens trans C18:1‐producing bacteria. In conclusion, the supplementation of diets with microalgae needs further investigation because it enhances the populations of methane‐producing bacteria and protozoa.  相似文献   
287.
Acacia hybrids offer a great potential for paper industry in Southeast Asia due to their fast growth and ability to grow on abandoned or marginal lands. Breeding Acacia hybrids with desirable traits can be achieved through marker assisted selection (MAS) breeding. To develop a MAS program requires development of linkage maps and QTL analysis. Two mapping populations were developed through interspecific hybridization for linkage mapping and QTL analysis. All seeds per pod were cultured initially to improve hybrid yield as quality and density of linkage mapping is affected by the size of the mapping population. Progenies from two mapping populations were field planted for phenotypic and genotypic evaluation at three locations in Malaysia, (1) Forest Research Institute Malaysia field station at Segamat, Johor, (2) Borneo Tree Seeds and Seedlings Supplies Sdn, Bhd. (BTS) field trial site at Bintulu, Sarawak, and (3) Asiaprima RCF field trial site at Lancang, Pahang. During field planting, mislabeling was reported at Segamat, Johor, and a similar problem was suspected for Bintulu, Sarawak. Early screening with two isozymes effectively selected hybrid progenies, and these hybrids were subsequently further confirmed by using species-specific SNPs. During field planting, clonal mislabeling was reported and later confirmed by using a small set of STMS markers. A large set of SNPs were also used to screen all ramets in both populations. A total of 65.36% mislabeled ramets were encountered in the wood density population and 60.34% in the fibre length mapping population. No interpopulation pollen contamination was detected because all ramets found their match within the same population in question. However, mislabeling was detected among ramets of the same population. Mislabeled individuals were identified and grouped as they originated from 93 pods for wood density and 53 pods for fibre length mapping populations. On average 2 meiotically unique seeds per pod (179 seeds/93 pods) for wood density and 3 meiotically unique seeds per pod (174 seeds/53 pods) for fibre length mapping population were found. A single step statistical method was used to evaluate the most informative set of SNPs that could subsequently be used for routine checks for mislabeling in multi-location field trials and for labelling superior clones to protect breeder’s rights. A preliminary set of SNPs with a high degree of informativeness was selected for the mislabeling analysis in conjunction with an assignment test. Two subsets were successfully identified, i.e., 51 SNPs for wood density and 64 SNPs for fibre length mapping populations to identify all mislabeled ramets which had been previously identified. Mislabeling seems to be a common problem due to the complexity involved in the production of mapping populations. Therefore, checking for mislabeling is imperative for breeding activities and for analyses such as linkage mapping in which a correlation between genotypic and phenotypic data is determined.  相似文献   
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