Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delim...Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delimitation of sparids in China remain unaddressed. In this study, we used mitochondrial cytochrome oxidase subunit ?(COI) and 16S ribosomal RNA(16S) genes to conduct DNA barcoding and species delimitation in eleven sparid species from the coastal waters of China. Based on Kimura-2 parameter genetic distances, the mean intraspecific/interspecific variation for COI and 16S were calculated as 0.004/0.152 and 0.002/0.072, respectively. All the conspecific individuals formed monophyletic clusters in neighbour-joining trees of both markers. An obvious barcoding gap was detected for each species, and a common genetic threshold of 1.3% sequence divergence was defined for species delimitation in both markers. Although the sequence variation of 16S was generally lower than that of COI, the results indicated that sparid species could be ef fectively and accurately identified and delimited by COI as well as 16S. Thus, we propose that the COI gene serve as the standard DNA barcode for sparids, and that the 16S gene could also be an ideal candidate barcode. Moreover, each of the six sparid species( Argyrops spinifer, Rhabdosargus sarba, Dentex hypselosomus, Acanthopagrus latus, Acanthopagrus australis and Acanthopagrus berda) showed high intraspecific divergence(>1.3% genetic threshold) with the remarkable geographic lineages in the Indo-West Pacific oceans, which supported that potential unrecognized cryptic species were in them. The potential cryptic diversity revealed here might be primarily attributed to the allopatric divergences caused by the long-term geographic isolation between the Indian and West Pacific oceans or between the opposite sides of the Indian Ocean. The results further suggest that a revision of taxonomic status of these species is required, followed by development of a biodiversity conservation strategy.展开更多
Wild and farmed fish generally dif fer in their nutritional composition. In this study, adult wild and farmed broadhead catfish( Clarias macrocephalus Günther, 1864) were collected and were assessed for various c...Wild and farmed fish generally dif fer in their nutritional composition. In this study, adult wild and farmed broadhead catfish( Clarias macrocephalus Günther, 1864) were collected and were assessed for various characteristics, namely morphometrics, digestive indexes, and flesh quality. The morphometrics(standard length, body depth, eye width, fin height and tentacle length) and the digestive indexes(intestosomatic index, digestosomatic index, perivisceral fat index and activities of pepsin and lipase) diff ered significantly between the groups(P <0.05) and can be used to distinguish wild fish from farmed fish. In terms of protein synthesis capacity and color, the flesh quality was similar between the groups. However, radical scavenging activities and reducing power were significantly higher in the wild fish than in the farmraised group. The thermal transition characteristics of sarcoplasmic proteins, as well as myosin denaturation enthalpy and fatty acid profiles(C18:2 n6, C20:0, C22:1 n9, C24:0, Σpolyunsaturated fatty acids, and Σn–6) also exhibited potential to enable calls about the fish origin. The proximate chemical composition of whole body did not diff er between the two fish populations. Our findings suggest bioindicators, in terms of morphometrics, digestive indexes and flesh quality, that can be used to identify the origin of fish for forensic purposes, of for conservation biology of this near threatened species. The new nutritional information may be of interest to marketing, consumers, and has a connection to nutritional eff ects on human health.展开更多
Abstract： This article introduces the development and application of the medium-pressure hydro-upgrading （MHUG） tech- nology developed by the Research Institute of Petroleum Processing （RIPP）. The MHUG technology...Abstract： This article introduces the development and application of the medium-pressure hydro-upgrading （MHUG） tech- nology developed by the Research Institute of Petroleum Processing （RIPP）. The MHUG technology based on the chemistry of diesel hydro-upgrading reactions has the advantages of flexible product slate and excellent product quality that can in- crease the cetane rating of diesel fuel up to more than 15 units. The hydrotreating and hydro-upgrading catalysts associated with the MHUG technology have outstanding performance to meet the demand of MHUG technology for hydro-saturation and selective ring-opening of aromatic rings. New MHUG process flow scheme can further increase the yield and selectivity of target products. Commercial application of multiple MHUG units has revealed that the MHUG technology designated for clean diesel production features good feedstock adaptability and operating stability.展开更多
Understanding the embryo physiology of Hizikia fusiformis（Harvey） Okamura will promote the development of artificial seedlings. In this study, H. fusiformis embryos were cultured under different environmental condit...Understanding the embryo physiology of Hizikia fusiformis（Harvey） Okamura will promote the development of artificial seedlings. In this study, H. fusiformis embryos were cultured under different environmental conditions, including different temperatures（15℃, 20℃, and 25℃）, sunlight intensities（100%, 50%, and 25% of full solar radiation） and types of UVR（UV-A and UV-B）. Then, we determined the lengths, maximal quantum yields（ Fv/Fm）, and survival rates of the embryos. The results showed that the embryos had the highest lengths, Fv/Fm values and survival percentages when cultured under a temperature of 20℃ and 25% sunlight intensity. The full level of solar radiation severely reduced the growth and survival ratios of the embryos. Hizikia embryos recovered within 2 h from the damage caused by short-term（30 min） high radiation（about 70% of full solar radiation） and UVR exposure. However, the viabilities of the embryos were significantly decreased after 4 h exposure to UVR. According to these results, we propose that culture conditions with indoor natural light and room temperature would be favorable for the growth, development and physiology of H izikia embryos.展开更多
Recently, increasing interest has been focused on the hydrolysis of carbohydrates to monosaccharides, among which, glucose and xylose as typical platform sugars can be used to produce chemicals and biofuels. As hetero...Recently, increasing interest has been focused on the hydrolysis of carbohydrates to monosaccharides, among which, glucose and xylose as typical platform sugars can be used to produce chemicals and biofuels. As heterogeneous catalysts, solid acids have gained extensive attention for biomass biorefinery and could replace the conventional process owing to their excellent properties, including acceptable acidity and easy separation. In particular, biochar-based solid acids derived from biomass are promising for biomass conversion owing to the low-cost of feedstocks and the simple preparation procedure. Herein, we attempt to provide a critical overview of biochar-based solid acids for hydrolysis of carbohydrates into glucose and xylose. The preparation methods and properties of biochar-based catalysts as well as the influence of their properties on catalytic performance were discussed in detail. We also highlight the major challenges facing the use of biochar-based solid acids for carbohydrate hydrolysis.展开更多
Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-...Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.展开更多
Fish supplies 25% of the total protein source in developing countries. A techno-economic analysis was performed for developing a good business proposal for aquaculture loans to enhance aquaculture development in Niger...Fish supplies 25% of the total protein source in developing countries. A techno-economic analysis was performed for developing a good business proposal for aquaculture loans to enhance aquaculture development in Nigeria. A case study of catfish Clarias gariepinus framing was conducted in Abeokuta North Local Government of Ogun State, Nigeria. The results show that the fixed cost is N18 338 per year, and the variable cost is N459 700 per year, accounting for the largest amount of the total; therefore, a profit of N43 289 per month can be made. Sensitivity analysis was performed to assess any risk(s) that associated with unfavorable changes in government policy with particular reference to monetary policy. Positive net present value shows that the investment in fish farm is economically feasible and the net investment ratio is 3.52. Also, the benefit-cost ratio is 2.17. The internal rate of return (IRR) is 21% showing that the enterprise is able to offset the interest being charged on the loan. It is therefore worthwhile to invest into fish farm business in the study area. The study suggests that to better sustain the local aquaculture business, the government should create a good conducive environment to foster development of the fish farming. Government intervention is urgently needed to solve problems such as in traditional land tenure, grant credit facilities and subsidies, to enhance the aquacultural development in the country.展开更多
The development ofinternet technology makes the aquatic products retailers change their traditional intermediary function in succession, and improve the information flow in the market relying on internet technology. T...The development ofinternet technology makes the aquatic products retailers change their traditional intermediary function in succession, and improve the information flow in the market relying on internet technology. This text aims to discuss the feasibility of adoption of drop-shipping model by the aquatic products e-retailers under ＂Internet ＋＂ and its influence factors, and provide the aquatic products e-retailers with relevant advices and suggestions on adoption of drop-shipping model.展开更多
The adverse impact of chemical agriculture in the India on the soil, water, environment and human health （of consumers and farm families） exacerbates rural poverty, even as agriculture productivity remains low. Poor...The adverse impact of chemical agriculture in the India on the soil, water, environment and human health （of consumers and farm families） exacerbates rural poverty, even as agriculture productivity remains low. Poor families, especially women, are the most affected by the health and environmental risks that are brought on by chemical agriculture, and they are hardest hit by the deteriorating productivity. On the other hand, the solid waste management problem in India is increasingly being felt in rural and urban areas. In this study, the author proposes to practice ofvermicomposting as technology for both sustainable agriculture and solid waste management, using the Hydro Bioreactor with vegetable waste. This technique is studied in the present research work which is simple and potentially inexpensive. Experiments were conducted to determine the changes in the physicochemical parameters and the dominant species of microorganisms at different temperatures during entire process of vermicomposting were investigated. The vermicompost developed in the hydro bioreactor was found to have comparatively high value of nutrients which can serve as natural fertilizer. The hydro bioreactor vermicomposting has proved very effective and efficient for developing compost from vegetable waste.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.31372532,41006084,41276166)the Project for Outstanding Young Teachers in Higher Education of Guangdong,China(No.Yq2013093)
文摘Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delimitation of sparids in China remain unaddressed. In this study, we used mitochondrial cytochrome oxidase subunit ?(COI) and 16S ribosomal RNA(16S) genes to conduct DNA barcoding and species delimitation in eleven sparid species from the coastal waters of China. Based on Kimura-2 parameter genetic distances, the mean intraspecific/interspecific variation for COI and 16S were calculated as 0.004/0.152 and 0.002/0.072, respectively. All the conspecific individuals formed monophyletic clusters in neighbour-joining trees of both markers. An obvious barcoding gap was detected for each species, and a common genetic threshold of 1.3% sequence divergence was defined for species delimitation in both markers. Although the sequence variation of 16S was generally lower than that of COI, the results indicated that sparid species could be ef fectively and accurately identified and delimited by COI as well as 16S. Thus, we propose that the COI gene serve as the standard DNA barcode for sparids, and that the 16S gene could also be an ideal candidate barcode. Moreover, each of the six sparid species( Argyrops spinifer, Rhabdosargus sarba, Dentex hypselosomus, Acanthopagrus latus, Acanthopagrus australis and Acanthopagrus berda) showed high intraspecific divergence(>1.3% genetic threshold) with the remarkable geographic lineages in the Indo-West Pacific oceans, which supported that potential unrecognized cryptic species were in them. The potential cryptic diversity revealed here might be primarily attributed to the allopatric divergences caused by the long-term geographic isolation between the Indian and West Pacific oceans or between the opposite sides of the Indian Ocean. The results further suggest that a revision of taxonomic status of these species is required, followed by development of a biodiversity conservation strategy.
基金Supported by the Research Fund from the Faculty of Science(No.1-2557-02-005)the Graduate School Research Support Funding for Thesis of the Prince of Songkla University
文摘Wild and farmed fish generally dif fer in their nutritional composition. In this study, adult wild and farmed broadhead catfish( Clarias macrocephalus Günther, 1864) were collected and were assessed for various characteristics, namely morphometrics, digestive indexes, and flesh quality. The morphometrics(standard length, body depth, eye width, fin height and tentacle length) and the digestive indexes(intestosomatic index, digestosomatic index, perivisceral fat index and activities of pepsin and lipase) diff ered significantly between the groups(P <0.05) and can be used to distinguish wild fish from farmed fish. In terms of protein synthesis capacity and color, the flesh quality was similar between the groups. However, radical scavenging activities and reducing power were significantly higher in the wild fish than in the farmraised group. The thermal transition characteristics of sarcoplasmic proteins, as well as myosin denaturation enthalpy and fatty acid profiles(C18:2 n6, C20:0, C22:1 n9, C24:0, Σpolyunsaturated fatty acids, and Σn–6) also exhibited potential to enable calls about the fish origin. The proximate chemical composition of whole body did not diff er between the two fish populations. Our findings suggest bioindicators, in terms of morphometrics, digestive indexes and flesh quality, that can be used to identify the origin of fish for forensic purposes, of for conservation biology of this near threatened species. The new nutritional information may be of interest to marketing, consumers, and has a connection to nutritional eff ects on human health.
文摘Abstract： This article introduces the development and application of the medium-pressure hydro-upgrading （MHUG） tech- nology developed by the Research Institute of Petroleum Processing （RIPP）. The MHUG technology based on the chemistry of diesel hydro-upgrading reactions has the advantages of flexible product slate and excellent product quality that can in- crease the cetane rating of diesel fuel up to more than 15 units. The hydrotreating and hydro-upgrading catalysts associated with the MHUG technology have outstanding performance to meet the demand of MHUG technology for hydro-saturation and selective ring-opening of aromatic rings. New MHUG process flow scheme can further increase the yield and selectivity of target products. Commercial application of multiple MHUG units has revealed that the MHUG technology designated for clean diesel production features good feedstock adaptability and operating stability.
基金Supported by the Science and Technology Planning Project of Guangdong,China(No.2016A020222001)
文摘Understanding the embryo physiology of Hizikia fusiformis（Harvey） Okamura will promote the development of artificial seedlings. In this study, H. fusiformis embryos were cultured under different environmental conditions, including different temperatures（15℃, 20℃, and 25℃）, sunlight intensities（100%, 50%, and 25% of full solar radiation） and types of UVR（UV-A and UV-B）. Then, we determined the lengths, maximal quantum yields（ Fv/Fm）, and survival rates of the embryos. The results showed that the embryos had the highest lengths, Fv/Fm values and survival percentages when cultured under a temperature of 20℃ and 25% sunlight intensity. The full level of solar radiation severely reduced the growth and survival ratios of the embryos. Hizikia embryos recovered within 2 h from the damage caused by short-term（30 min） high radiation（about 70% of full solar radiation） and UVR exposure. However, the viabilities of the embryos were significantly decreased after 4 h exposure to UVR. According to these results, we propose that culture conditions with indoor natural light and room temperature would be favorable for the growth, development and physiology of H izikia embryos.
基金supported by grants from the Program for National Natural Science Foundation of China(No.21576103)the Guangdong Program for Support of Top-notch Young Professionals(No.2016TQ03Z585)the Guangzhou Science and Technology Plan Project(No.201707010059)
文摘Recently, increasing interest has been focused on the hydrolysis of carbohydrates to monosaccharides, among which, glucose and xylose as typical platform sugars can be used to produce chemicals and biofuels. As heterogeneous catalysts, solid acids have gained extensive attention for biomass biorefinery and could replace the conventional process owing to their excellent properties, including acceptable acidity and easy separation. In particular, biochar-based solid acids derived from biomass are promising for biomass conversion owing to the low-cost of feedstocks and the simple preparation procedure. Herein, we attempt to provide a critical overview of biochar-based solid acids for hydrolysis of carbohydrates into glucose and xylose. The preparation methods and properties of biochar-based catalysts as well as the influence of their properties on catalytic performance were discussed in detail. We also highlight the major challenges facing the use of biochar-based solid acids for carbohydrate hydrolysis.
文摘Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.
文摘Fish supplies 25% of the total protein source in developing countries. A techno-economic analysis was performed for developing a good business proposal for aquaculture loans to enhance aquaculture development in Nigeria. A case study of catfish Clarias gariepinus framing was conducted in Abeokuta North Local Government of Ogun State, Nigeria. The results show that the fixed cost is N18 338 per year, and the variable cost is N459 700 per year, accounting for the largest amount of the total; therefore, a profit of N43 289 per month can be made. Sensitivity analysis was performed to assess any risk(s) that associated with unfavorable changes in government policy with particular reference to monetary policy. Positive net present value shows that the investment in fish farm is economically feasible and the net investment ratio is 3.52. Also, the benefit-cost ratio is 2.17. The internal rate of return (IRR) is 21% showing that the enterprise is able to offset the interest being charged on the loan. It is therefore worthwhile to invest into fish farm business in the study area. The study suggests that to better sustain the local aquaculture business, the government should create a good conducive environment to foster development of the fish farming. Government intervention is urgently needed to solve problems such as in traditional land tenure, grant credit facilities and subsidies, to enhance the aquacultural development in the country.
文摘The development ofinternet technology makes the aquatic products retailers change their traditional intermediary function in succession, and improve the information flow in the market relying on internet technology. This text aims to discuss the feasibility of adoption of drop-shipping model by the aquatic products e-retailers under ＂Internet ＋＂ and its influence factors, and provide the aquatic products e-retailers with relevant advices and suggestions on adoption of drop-shipping model.
文摘The adverse impact of chemical agriculture in the India on the soil, water, environment and human health （of consumers and farm families） exacerbates rural poverty, even as agriculture productivity remains low. Poor families, especially women, are the most affected by the health and environmental risks that are brought on by chemical agriculture, and they are hardest hit by the deteriorating productivity. On the other hand, the solid waste management problem in India is increasingly being felt in rural and urban areas. In this study, the author proposes to practice ofvermicomposting as technology for both sustainable agriculture and solid waste management, using the Hydro Bioreactor with vegetable waste. This technique is studied in the present research work which is simple and potentially inexpensive. Experiments were conducted to determine the changes in the physicochemical parameters and the dominant species of microorganisms at different temperatures during entire process of vermicomposting were investigated. The vermicompost developed in the hydro bioreactor was found to have comparatively high value of nutrients which can serve as natural fertilizer. The hydro bioreactor vermicomposting has proved very effective and efficient for developing compost from vegetable waste.
