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61.
Journal of Crop Science and Biotechnology - There is great interest in the enhancement of isoflavones as one of the functional ingredients in soybean. This study aimed to investigate the effects of...  相似文献   
62.
Abalones ( Haliotis species) are a popular delicacy and commonly preserved in dried form either whole or in slices or small pieces for consumption in Asian countries. Driven by the huge profit from trading abalones, dishonest traders may substitute other molluscan species for processed abalone, of which the morphological characteristics are frequently lost in the processed form. For protection of consumer rights and law enforcement against fraud, there is a need for an effective methodology to differentiate between fake and genuine abalone. This paper describes a method (validated according to the international forensic guidelines provided by SWGDAM) for the identification of fake abalone species using forensically informative nucleotide sequence (FINS) analysis. A study of the local market revealed that many claimed "abalone slice" samples on sale are not genuine. The fake abalone samples were found to be either volutids of the genus Cymbium (93%) or the muricid Concholepas concholepas (7%). This is the first report of Cymbium species being used for the preparation and sale as "abalone" in dried sliced form in Hong Kong.  相似文献   
63.
The Vietnamese Ban pig is a precious genetic resource that needs to be preserved. In vitro embryo production from in vitro matured (IVM) oocytes is an important tool for the utilization of cryopreserved porcine sperm. The aim of this study was to compare two media for the IVM of Ban pig oocytes. Immature oocytes were subjected to IVM either in a non‐defined (TCM‐199 + pig follicular fluid) or in a defined base medium (POM + epidermal growth factor). At the end of IVM, the oocytes were in vitro fertilized (IVF) with frozen Ban sperm. Ten hours after IVF, the oocytes were either subjected to orcein staining to check fertilization and maturation status or cultured in vitro for 7 days. There was no difference between the two IVM media in terms of percentages of oocyte maturation and blastocyst production. However, the percentage of male pronuclear formation after IVF and the total cell numbers in blastocysts were higher with the defined system. Zygotes obtained by the two IVM systems survived vitrification at similar rates. In conclusion, the two IVM systems were both effective for the production of Ban pig embryos; however, better embryo quality was achieved with the defined one.  相似文献   
64.
Ginseng is an important medicinal plant, but almost no genomic information is known for it. For the primary step to understand the Panax genome, we inspected the chloroplast genome sequence diversity and used that to infer the evolution of Panax species using them. We inspected a total of 101 intergenic spacers (IGS) covering 44,563 bp (96.8 % of the total IGS) from four Panax species. Diversity was inspected by three steps: gel electrophoresis, high resolution melting (HRM) analysis, and further confirmation by sequencing. Even though low levels of InDel polymorphism were detected by gel electrophoresis, high levels of reproducible polymorphisms were identified by HRM analysis. Sequencing of the HRM-polymorphic spaces and pair-wise multiple sequence alignments revealed up to 247 sequence variations between species. We have identified 62 IGS showing polymorphism between species. Among them, the trnE-trnT, trnT-psbD, ndhF-rpl32, and rpl14-rpl16 spaces are more informative for studying the diversity of Panax relatives. Phylogenetic analysis and molecular evolution studies revealed that P. notoginseng is most diverged from the other Panax species, with a nucleotide substitution rate of 0.0039. P. quinquefolius shows a close relationship with P. ginseng and P. japonicus, with a nucleotide substitution rate of 0.0009. Meanwhile, no sequence variation was detected between P. ginseng and P. japonicus. Calculation of molecular clocks revealed that P. notoginseng diverged more than 1.30 million years ago from the other Panax species and then, P. quinquefolius diverged from P. ginseng by migration in the American continent more than 0.29 million years ago.  相似文献   
65.
Abstract

Soil dispersion induces soil erosion and colloidal leaching. Nutrients are lost at the same time and this causes water contamination. Phosphate is an essential element for living organisms. Because phosphate influences soil dispersion and it is an important limited resource, this influence must be evaluated well in order to diminish negative effects on soil structure. In this paper, we firstly evaluated the influence of phosphate sorption on soil dispersion by calculating repulsive potential energy between soil particles. Ferralsol, which is a typical soil in rainy tropical regions, was used as the material. The dispersion-flocculation phenomena were investigated with absorbance of soil suspension under different pH, phosphate adsorption and electrolyte concentration in an Na-NO3-PO4 system. The repulsive potential energy was calculated based on the diffuse double layer theory and the measured zeta potential. We indicated that the measured absorbance increased with the increase of the repulsive potential energy. The repulsive potential energy increased with increasing phosphate sorption up to about 5 to 20 mmol kg?1 at all pH, and it induced the soil dispersion, because phosphate sorption increased the negative charge of the soil. After its peak, it decreased with increasing phosphate sorption because the electrolyte concentration increased and the electrolyte screened the electric field near the soil surface. The repulsive potential energy also increased with increasing pH because of the increase of the negative charge of the soil. Even at low pH, after a certain amount of phosphate sorption, the soil dispersed due to the increase of repulsive potential energy, although the soil flocculated before phosphate application. Because the soil dispersion causes soil and phosphorus loss, the influence of soil pH and phosphate sorption on the soil dispersion should be considered for good soil management.  相似文献   
66.
Growing aquatic species in inland saline water (ISW) is one way to reduce the adverse impact of ISW to agriculture farms. This 84‐day laboratory‐trial was conducted to study the growth of Sargassum linearifolium cultured in ocean water (OW), ISW, ISW fortified with potassium equivalent to 100% (ISW100), 66% (ISW66) and 33% (ISW33) of potassium in OW at 35 g/L. The biomass and cumulative specific growth rate (SGR) of S. linearifolium increased significantly (< .05) with increased potassium in ISW until 56 days and then declined. The ISW100 and OW resulted in similar growth patterns and yielded peak biomass at day 42, proving static biomass for the next 28 days before declining. The biomass of S. linearifolium cultured in ISW and ISW33 significantly (p < .05) decreased and was lower than in ISW100 and died after day 56. The SGR of S. linearifolium in OW, ISW100 and ISW66 levelled off and showed no difference during the first 56 days. The S. linearifolium biomass and SGR negatively and significantly (p < .05) correlated with the concentrations of nitrate, phosphate in all waters. The increased potassium concentration in ISW similar to its concentration in SW brought the growth of S. linearifolium cultured to a level that was similar in OW.  相似文献   
67.
The consumption of energy inputs in agricultural production has been increasing rapidly during the past decades. However, given the limitations and costs of non-renewable energy, increasing production while using the least energy possible has become a major concern of most nations. Prompted by this concern, we conducted a face-to-face survey of 90 farming households in Thai Nguyen Province, Vietnam, to find out how energy is being used in agriculture and, specifically, in their rice production. Through analysis of energy input–output balances, combined with economic efficiency analysis, a comparison was made of conventional and SRI methods of rice production. The study found that applying the SRI method can save around 23% of energy inputs, while increasing energy outputs by 11%. Economic benefits per hectare also rise by more than 8 million dong (USD 364) compared to those under the conventional cultivation system. The study also showed conflicts between the energy and economic balances for manual compared with machine ploughing operations. This study contributes to providing an overview of energy consumption in rice cultivation at the household level. Its findings can help stakeholders to assess current policies and make better decisions on the uses of energy in agricultural production. In addition, the comprehensive approach taken here to analysing energy use and efficiency could expand the analysis and comparison of energy uses at sectoral or activity level—still a new field in Vietnam and many other countries.  相似文献   
68.
为实现灌区测量水规范化、标准化和自动化提供参考依据,保证灌区有限水资源科学管理与合理配置,达到公平和高效的利用目的,针对宁夏灌区测量水技术的发展现状进行了综合阐述.总结宁夏目前所采用的量水方法和在生产实际应用中存在的问题,提出灌区量水技术的发展趋势,通过提高灌区测量水的技术装备和测试手段,旨在提高灌区测量水技术水平和精度的有效保证.  相似文献   
69.
Detection of tilapia lake virus (TiLV) in tilapines is mainly from visceral organs of killed fish. However, lethal sampling might not be viable to broodstock and economically important ornamental cichlids. To contribute towards screening of the virus in asymptomatic infected fish, a subclinically infected population of Nile tilapia adults obtained from a local farm was preliminarily tested to compare different non‐lethal sampling methods, for example liver biopsy, gill biopsy, fin clip, mucus, faeces and blood for detection of TiLV. Only liver and blood samples gave positive results by PCR. Since blood sampling is relatively simpler, it was further used for five naturally co‐cultured juvenile fish species from above‐mentioned farm including 40 red tilapia broodstock and 20 Nile tilapia adults from two other different farms. The results showed that from the tested fish, 4 of 5 Nile tilapia, 2 of 5 hybrid red tilapia and 3 of 5 giant gourami blood samples tested positive, while 38 of 40 blood samples of red tilapia tested positive for TiLV in second‐step PCR. Sequencing representative PCR amplicons of positive samples confirmed sequence identity to TiLV. In conclusion, both blood and liver biopsy are practical non‐destructive sampling platforms for TiLV screening in cichlids with blood being more convenient, especially for tilapia broodstock.  相似文献   
70.
Accumulating data suggest a relationship between chemerin and energy metabolism. Our group previously described gene cloning, expression analysis and the regulatory mechanism of chemerin and its own receptor in mice and cattle. The objective of the present study was to investigate the physiological effect of chemerin on endocrine changes and energy metabolism in sheep using a biologically stable chemerin analog. The chemerin analog was intravenously administrated (100 or 500 µg/head) to sheep, and plasma insulin and metabolites (glucose, nonesterified fatty acids (NEFA), triglyceride, total cholesterol and high‐density lipoprotein (HDL) cholesterol) were analyzed. The chemerin analog dramatically increased the insulin levels, and glucose levels were decreased. NEFA levels were slightly decreased at 20 min but then increased gradually from 60 to 180 min after analog administration. In addition, injection of the chemerin analog immediately increased triglyceride and total cholesterol but not HDL levels. These results suggested that chemerin analog regulated insulin secretion related to glucose metabolism and the release of triglycerides in sheep in vivo. This study provides new information about endocrine and metabolic changes in response to chemerin in sheep.  相似文献   
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