Field trials were conducted at the University of Uyo Teaching and Research Farm in 2009/2010 and 2010/2011 to evaluate cassava yield, garrification traits, and economic returns as influenced by genotypes grown in an u...Field trials were conducted at the University of Uyo Teaching and Research Farm in 2009/2010 and 2010/2011 to evaluate cassava yield, garrification traits, and economic returns as influenced by genotypes grown in an ultisol. Uyo is located between latitudes 4°30' and 5°27'N and longitudes 7°50'E and 80°20'E. The area, which lies within the humid tropical rainforest zone of southeastern Nigeria, has an annual mean rainfall of 2500 mm with a bimodal rainfall pattern, monthly sunshine of 3.14 hours, and a mean annual temperature of 28°C. The experimental site was previously put into cultivation of some arable crops such as fluted pumpkin, okra, and waterleaf before it was fallowed for two years. A randomized complete block design, replicated three times was used. Treatments were 16 cassava genotypes (AR1-82, NR02/0028, NR03/0174, CR12-45, NR03/0211, TMS98/2132, TMS01/1206, TMS01/1368, TMS01/1371, CR36-5, NR02/0007, NR03/0155, AR37-108, TMS01/1412, TMS30572 and local best variety “Obubit okpo”). Results obtained via combined (pooled) analysis of the two seasons indicated that cassava yield differed significantly among the genotypes. NR02/0018 (42.50 t/ha) out-yielded others by 17% - 52% followed by NR 02/0007 (35.42 t/ha), and NR 03/0155 (32.08 t/ha). TMS 98/2132 had the most preferred garrification attributes followed by NR 02/0018, NR 02/0007, and NR03/01155. NR 02/0018 genotype gave the highest economic returns followed by NR 02/0007 and NR03/0155. NR02/0018 superseded others in yield, garrification traits, and economic returns, which is therefore recommended.展开更多
This review article examines the relationship between health and economic development,highlighting the economic benefits of investing in health.The rise of non-communicable diseases(NCDs)and the COVID-19 pandemic have...This review article examines the relationship between health and economic development,highlighting the economic benefits of investing in health.The rise of non-communicable diseases(NCDs)and the COVID-19 pandemic have exposed high demand for increased investment in health as well as critical gaps in the global health system,particularly in low-and middle-income countries,where investments in primary healthcare and innovations in health technologies are lacking.The article emphasizes the importance of examining the economic impact of health,providing a summary of the different pathways through which health impacts the economy and reviewing various economic analyses,including a novel methodology called the health-augmented macroeconomic model(HMM)for evaluating the macroeconomic value of investing in health.The article suggests that reducing disease burdens can effectively generate sizable economic returns,and it is vital to integrate the concept of economic value in health policies and interventions.展开更多
The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return...The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return of Pelodiscus sinensis cultured in ponds.P.sinensis were stocked at densities of 1 ind./m^2(LD:low stocking density) and 2 ind./m^2(HD:high stocking density) in 3 000-m^2 ponds,with three replicate ponds for each density.P.sinensis juveniles were fed with a commercial dry pellet feed of 46% crude protein and minced fillet of silver carp ans cultured for 122 days.The results showed that the levels of total nitrogen(TN),total phosphorous(TP),Chlorophyll-a(Chl.a) and turbidity in LD treatment were significantly lower than those in HD treatment(P<0.05).The mean TN and TP concentration in LD treatment was 29.3% and 35.7% lower compared to the HD treatment at the end of the experiment,respectively.Mean survival rates,final weight,average growth rates and PER were significantly higher in LD treatment compared with the HD treatment(P<0.05),respectively.Production was significantly affected by stocking density,which was higher in HD treatment,but the net income was higher in LD treatment.The results suggest that turtles with mean weight 55.6 g rearing at a low stocking density(1 ind./m^2) in ponds had a positive effect on overall economic return and was effective at improving turtle growth performance and water quality.展开更多
The recent growth of the global petroleum refining industry and the main technologies and measures for China to process inferior crude oil were introduced. The main technologies and measures include the control over e...The recent growth of the global petroleum refining industry and the main technologies and measures for China to process inferior crude oil were introduced. The main technologies and measures include the control over equipment corrosion induced by sour and acidic crude, in particular the corrosion of atmospheric and vacuum distillation units, the development of technology for processing inferior residue, and the development of desulfurization technology and sulfur recovery technology in the course of processing of petroleum products. In order to meet the needs for national economic development, China’s refining enterprises will uninterruptedly develop and prefect technologies for processing inferior crude, enhance the process and equipment management, sum up the experience for better processing of inferior crude, so as to provide high-quality oil products and petrochemical feedstocks to public with better economic return.展开更多
This study analyzed the financial profitability and the impacts of socioeconomic factors on hiring an external labor force in tilapia farming in Southern Togo.We obtained the primary data from 75 randomly selected til...This study analyzed the financial profitability and the impacts of socioeconomic factors on hiring an external labor force in tilapia farming in Southern Togo.We obtained the primary data from 75 randomly selected tilapia farmers for socioeconomic analysis by a structured questionnaire.Logit regression and return on investment(ROI)were performed to analyze the influence of socioeconomic factors on the decision of tilapia farmers to hire an external labor force and financial profitability of tilapia farming in the study area,respectively.The results indicate that tilapia farming contributes to employment opportunities in the study area.However,the key variables such as economic diversification,farming experience and educational attainment significantly affect the farmers’decision to hire an external labor force in their farms.Furthermore,tilapia farming is a profitable activity based on the positive mean gross margin and mean net farm income.The ROI was 0.31,which implies that a return of USD 0.31 was obtained for the investment of every single dollar.The government must pay more attention by organizing training or re-training workshops for tilapia farmers,which would improve their socio-economic status.展开更多
Loess Plateau of China is a typical dryland agricultural area.Agriculture there has transformed from food shortage toward green development over the past seven decades,and has achieved world-renowned achievements.Duri...Loess Plateau of China is a typical dryland agricultural area.Agriculture there has transformed from food shortage toward green development over the past seven decades,and has achieved world-renowned achievements.During1950–1980,the population increased from 42 to 77 million,increasing grain production to meet food demand of rapid population growth was the greatest challenge.Engineering measures such as terracing and check-dam were the crucial strategies to increase crop production.From 1981 to 2000,most of agronomic measures played a key role in increasing crops yield,and a series of policy support has benefited millions of smallholders.As expected,these measures and policies greatly increased crop production and basically achieved food security;but,low per capita GDP(only about 620 USD in 2000)was still a big challenge.During 2001–2015,the increase in agricultural and non-agricultural income together supported the increase in farmer income to5781 USD·yr^(–1).Intensive agriculture that relies heavily on chemicals increased crop productivity by 56%.Steadfast policy support such as"Grain for Green Program"had an overwhelming advantage in protecting the natural ecological environment.In the new era,the integration of science and technology innovations,policy support and positive societal factors will be the golden key to further improve food production,protect environment,and increase smallholder income.展开更多
Carbon trading and carbon offset markets are potential policy options for mitigating greenhouse gas emissions and climate change. A price on carbon is expected to generate demand for carbon offsets. In a market-based ...Carbon trading and carbon offset markets are potential policy options for mitigating greenhouse gas emissions and climate change. A price on carbon is expected to generate demand for carbon offsets. In a market-based framework, the carbon price should be high enough to compensate for opportunity costs. We studied a highly-modified agricultural system in the Guanzhong–Tianshui economic region of China that is typical of many temperate agricultural zones in western China. We quantified the economic returns from agriculture and from carbon plantings(both monoculture and ecological plantings) under five carbon-price scenarios. The mean carbon sequestration is 34 Mg·hm^(–2)·a^(–1), and the average annual payment increased to 1146 CNY·hm^(–2) at a medium carbon price of 50 CNY·Mg^(–1) CO_2^(–e). Thus, areas of high priority for conservation and restoration may be restored relatively cheaply in the presence of a carbon market.Overall, however, less carbon is sequestered by ecological plantings(i.e., mixed native trees and shrubs) compared to agriculture.展开更多
The reasonable assessment of maize varieties in different ecological regions can allow temperature resources to be fully exploited and reach the goal of high yield and efficiency and is thus an important direction of ...The reasonable assessment of maize varieties in different ecological regions can allow temperature resources to be fully exploited and reach the goal of high yield and efficiency and is thus an important direction of modern maize development in China.In this study,a logistic power nonlinear growth model was used to simulate the accumulated temperature required for kernel dehydration to moisture contents of 25%,20%,and 16%for various maize cultivar,which were divided into six types based on the accumulated temperature required for kernel dehydration to a moisture content of 25%.The relationship between the yield of maize cultivars and the accumulated temperature required for kernel dehydration to a moisture content of 25%was found to follow a unary function model.Changing the planted maize variety was found to increase economic returns by more than 7000 RMB/hm2 in Ningxia,Northwest China.Under the conditions of mechanical grain harvesting,economic benefits can be further increased by means of selecting high yields and fast-dehydrating varieties,selling when the grain dehydration is below 16%.A better way to achieve grain dehydration to a moisture content below 16%is to postpone the harvest date as much as possible rather than drying after the harvest at physiological maturity.The areas of various types of maize varieties can be dehydrated to moisture contents of 25%,20%,and 16%were marked.Based on the distribution of heat resources in different regions of Ningxia from the normal sowing date to October 31 before winter irrigation,the appropriate cultivars for various regions in the province were determined based on production benefits.Therefore,in different areas of Ningxia,selecting suitable maize varieties according to temperature resources can reach a high yield and mechanical kernel harvesting,and ultimately obtain higher economic benefits.展开更多
By probing into the relationship of senior students’demand for“internationalization”,students’expected economic returns in future careers,and their individual concept of modernity,this study attempts to explore se...By probing into the relationship of senior students’demand for“internationalization”,students’expected economic returns in future careers,and their individual concept of modernity,this study attempts to explore several factors that are influencing the demand for overseas higher education.展开更多
文摘Field trials were conducted at the University of Uyo Teaching and Research Farm in 2009/2010 and 2010/2011 to evaluate cassava yield, garrification traits, and economic returns as influenced by genotypes grown in an ultisol. Uyo is located between latitudes 4°30' and 5°27'N and longitudes 7°50'E and 80°20'E. The area, which lies within the humid tropical rainforest zone of southeastern Nigeria, has an annual mean rainfall of 2500 mm with a bimodal rainfall pattern, monthly sunshine of 3.14 hours, and a mean annual temperature of 28°C. The experimental site was previously put into cultivation of some arable crops such as fluted pumpkin, okra, and waterleaf before it was fallowed for two years. A randomized complete block design, replicated three times was used. Treatments were 16 cassava genotypes (AR1-82, NR02/0028, NR03/0174, CR12-45, NR03/0211, TMS98/2132, TMS01/1206, TMS01/1368, TMS01/1371, CR36-5, NR02/0007, NR03/0155, AR37-108, TMS01/1412, TMS30572 and local best variety “Obubit okpo”). Results obtained via combined (pooled) analysis of the two seasons indicated that cassava yield differed significantly among the genotypes. NR02/0018 (42.50 t/ha) out-yielded others by 17% - 52% followed by NR 02/0007 (35.42 t/ha), and NR 03/0155 (32.08 t/ha). TMS 98/2132 had the most preferred garrification attributes followed by NR 02/0018, NR 02/0007, and NR03/01155. NR 02/0018 genotype gave the highest economic returns followed by NR 02/0007 and NR03/0155. NR02/0018 superseded others in yield, garrification traits, and economic returns, which is therefore recommended.
文摘This review article examines the relationship between health and economic development,highlighting the economic benefits of investing in health.The rise of non-communicable diseases(NCDs)and the COVID-19 pandemic have exposed high demand for increased investment in health as well as critical gaps in the global health system,particularly in low-and middle-income countries,where investments in primary healthcare and innovations in health technologies are lacking.The article emphasizes the importance of examining the economic impact of health,providing a summary of the different pathways through which health impacts the economy and reviewing various economic analyses,including a novel methodology called the health-augmented macroeconomic model(HMM)for evaluating the macroeconomic value of investing in health.The article suggests that reducing disease burdens can effectively generate sizable economic returns,and it is vital to integrate the concept of economic value in health policies and interventions.
基金Supported by a grant from the National Scientific and Technological Supporting Program of China(No.2012BAD27B02-6)the Opening Foundation of the Jiangsu Engineering Laboratory for Characteristic Aquatic Species Breeding(No.CASB1306)the Knowledge Innovation Project of the Chinese Academy of Sciences(KSCX2-YW-N-47-06)
文摘The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return of Pelodiscus sinensis cultured in ponds.P.sinensis were stocked at densities of 1 ind./m^2(LD:low stocking density) and 2 ind./m^2(HD:high stocking density) in 3 000-m^2 ponds,with three replicate ponds for each density.P.sinensis juveniles were fed with a commercial dry pellet feed of 46% crude protein and minced fillet of silver carp ans cultured for 122 days.The results showed that the levels of total nitrogen(TN),total phosphorous(TP),Chlorophyll-a(Chl.a) and turbidity in LD treatment were significantly lower than those in HD treatment(P<0.05).The mean TN and TP concentration in LD treatment was 29.3% and 35.7% lower compared to the HD treatment at the end of the experiment,respectively.Mean survival rates,final weight,average growth rates and PER were significantly higher in LD treatment compared with the HD treatment(P<0.05),respectively.Production was significantly affected by stocking density,which was higher in HD treatment,but the net income was higher in LD treatment.The results suggest that turtles with mean weight 55.6 g rearing at a low stocking density(1 ind./m^2) in ponds had a positive effect on overall economic return and was effective at improving turtle growth performance and water quality.
文摘The recent growth of the global petroleum refining industry and the main technologies and measures for China to process inferior crude oil were introduced. The main technologies and measures include the control over equipment corrosion induced by sour and acidic crude, in particular the corrosion of atmospheric and vacuum distillation units, the development of technology for processing inferior residue, and the development of desulfurization technology and sulfur recovery technology in the course of processing of petroleum products. In order to meet the needs for national economic development, China’s refining enterprises will uninterruptedly develop and prefect technologies for processing inferior crude, enhance the process and equipment management, sum up the experience for better processing of inferior crude, so as to provide high-quality oil products and petrochemical feedstocks to public with better economic return.
文摘This study analyzed the financial profitability and the impacts of socioeconomic factors on hiring an external labor force in tilapia farming in Southern Togo.We obtained the primary data from 75 randomly selected tilapia farmers for socioeconomic analysis by a structured questionnaire.Logit regression and return on investment(ROI)were performed to analyze the influence of socioeconomic factors on the decision of tilapia farmers to hire an external labor force and financial profitability of tilapia farming in the study area,respectively.The results indicate that tilapia farming contributes to employment opportunities in the study area.However,the key variables such as economic diversification,farming experience and educational attainment significantly affect the farmers’decision to hire an external labor force in their farms.Furthermore,tilapia farming is a profitable activity based on the positive mean gross margin and mean net farm income.The ROI was 0.31,which implies that a return of USD 0.31 was obtained for the investment of every single dollar.The government must pay more attention by organizing training or re-training workshops for tilapia farmers,which would improve their socio-economic status.
基金supported by the National Natural Science Foundation of China(31902120)Science and Technology Plan Project of Qinghai Province(2019-NK-A11-02)Fundamental Research Funds for Central University(Northwest A&F University,2452018110)。
文摘Loess Plateau of China is a typical dryland agricultural area.Agriculture there has transformed from food shortage toward green development over the past seven decades,and has achieved world-renowned achievements.During1950–1980,the population increased from 42 to 77 million,increasing grain production to meet food demand of rapid population growth was the greatest challenge.Engineering measures such as terracing and check-dam were the crucial strategies to increase crop production.From 1981 to 2000,most of agronomic measures played a key role in increasing crops yield,and a series of policy support has benefited millions of smallholders.As expected,these measures and policies greatly increased crop production and basically achieved food security;but,low per capita GDP(only about 620 USD in 2000)was still a big challenge.During 2001–2015,the increase in agricultural and non-agricultural income together supported the increase in farmer income to5781 USD·yr^(–1).Intensive agriculture that relies heavily on chemicals increased crop productivity by 56%.Steadfast policy support such as"Grain for Green Program"had an overwhelming advantage in protecting the natural ecological environment.In the new era,the integration of science and technology innovations,policy support and positive societal factors will be the golden key to further improve food production,protect environment,and increase smallholder income.
基金supported by the National Natural Science Foundation of China (41371020)Fundamental Research Funds for the Central Universities (GK201502010)+2 种基金China Postdoctoral Science Foundation on the 58th Group (2015M582706)Postdoctoral Scientific Research Project Foundation of Shaanxi Province in 2015China 111 Project (B12007)
文摘Carbon trading and carbon offset markets are potential policy options for mitigating greenhouse gas emissions and climate change. A price on carbon is expected to generate demand for carbon offsets. In a market-based framework, the carbon price should be high enough to compensate for opportunity costs. We studied a highly-modified agricultural system in the Guanzhong–Tianshui economic region of China that is typical of many temperate agricultural zones in western China. We quantified the economic returns from agriculture and from carbon plantings(both monoculture and ecological plantings) under five carbon-price scenarios. The mean carbon sequestration is 34 Mg·hm^(–2)·a^(–1), and the average annual payment increased to 1146 CNY·hm^(–2) at a medium carbon price of 50 CNY·Mg^(–1) CO_2^(–e). Thus, areas of high priority for conservation and restoration may be restored relatively cheaply in the presence of a carbon market.Overall, however, less carbon is sequestered by ecological plantings(i.e., mixed native trees and shrubs) compared to agriculture.
基金This research was supported by the National Key Research and Development Program of China(2016YFD0300110)the National Natural Science Foundation of China(31971849)+1 种基金the National Maize Industrial Technology System of China(CARS-02)the Science and Technology Innovation Project of the Chinese Academy of Agricultural Science and the Key Research and Development Program of Ningxia(2018BBF02018)for their financial support.
文摘The reasonable assessment of maize varieties in different ecological regions can allow temperature resources to be fully exploited and reach the goal of high yield and efficiency and is thus an important direction of modern maize development in China.In this study,a logistic power nonlinear growth model was used to simulate the accumulated temperature required for kernel dehydration to moisture contents of 25%,20%,and 16%for various maize cultivar,which were divided into six types based on the accumulated temperature required for kernel dehydration to a moisture content of 25%.The relationship between the yield of maize cultivars and the accumulated temperature required for kernel dehydration to a moisture content of 25%was found to follow a unary function model.Changing the planted maize variety was found to increase economic returns by more than 7000 RMB/hm2 in Ningxia,Northwest China.Under the conditions of mechanical grain harvesting,economic benefits can be further increased by means of selecting high yields and fast-dehydrating varieties,selling when the grain dehydration is below 16%.A better way to achieve grain dehydration to a moisture content below 16%is to postpone the harvest date as much as possible rather than drying after the harvest at physiological maturity.The areas of various types of maize varieties can be dehydrated to moisture contents of 25%,20%,and 16%were marked.Based on the distribution of heat resources in different regions of Ningxia from the normal sowing date to October 31 before winter irrigation,the appropriate cultivars for various regions in the province were determined based on production benefits.Therefore,in different areas of Ningxia,selecting suitable maize varieties according to temperature resources can reach a high yield and mechanical kernel harvesting,and ultimately obtain higher economic benefits.
基金The authors are grateful to the Study of Demand for Higher Education with Reference to Educational Finance in HK and China’s Mainland.(ARGC Funded Research Project,2003-2004).
文摘By probing into the relationship of senior students’demand for“internationalization”,students’expected economic returns in future careers,and their individual concept of modernity,this study attempts to explore several factors that are influencing the demand for overseas higher education.
