The agro-pasturage ecotone in northern China is not only an important green ecosystem barrier but also an important economic belt. However, the extensive operation manner and harsh natural surroundings lead to the gra...The agro-pasturage ecotone in northern China is not only an important green ecosystem barrier but also an important economic belt. However, the extensive operation manner and harsh natural surroundings lead to the grassland degradation, low agricultural productivity and people living in poverty. In our study, the result has shown that the aboveground biomass and economic benefits of improved grassland, artificial perennial grassland and silage farmland have been increased greatly. Therefore, the development and construction of high-yield silage farmland and artificial perennial grassland in agro-pasturage ecotone not only increase the economic benefits but also protect the ecological environment.展开更多
Identifying the factors affecting drinking water consumption is essential to the rational management of water resources and effective environment protection. In this study, the effects of the factors on rural drinking...Identifying the factors affecting drinking water consumption is essential to the rational management of water resources and effective environment protection. In this study, the effects of the factors on rural drinking water demand were studied using the adaptive neuro-fuzzy inference system (ANFIS) and hybrid models, such as the ANFIS-genetic algorithm (GA), ANFIS-particle swarm optimization (PSO), and support vector machine (SVM)-simulated annealing (SA). The rural areas of Hamadan Province in Iran were selected for the case study. Five drinking water consumption factors were selected for the assessment according to the literature, data availability, and the characteristics of the study area (such as precipitation, relative humidity, temperature, the number of subscribers, and water price). The results showed that the standard errors of ANFIS, ANFIS-GA, ANFIS-PSO, and SVM-SA were 0.669, 0.619, 0.705, and 0.578, respectively. Therefore, the hybrid model SVM-SA outperformed other models. The sensitivity analysis showed that of the parameters affecting drinking water consumption, the number of subscribers significantly affected the water consumption rate, while the average temperature was the least significant factor. Water price was a factor that could be easily controlled, but it was always one of the least effective parameters due to the low water fee.展开更多
Objective:Paid sick leave(PSL)laws mandate employers give workers paid time off when they are sick or injured.This current study aims to examine whether access to PSL is associated with healthcare utilization and heal...Objective:Paid sick leave(PSL)laws mandate employers give workers paid time off when they are sick or injured.This current study aims to examine whether access to PSL is associated with healthcare utilization and health outcomes and to summarize the types of utilization and outcomes which have been reported to be associated with PSL.Methods:We conducted a rapid evidence review.Our search of seven databases,including Medline,Embase,PsycINFO,Cochrane Library,CINAHL,Scopus,and JSTOR,on September 21,2020,identified 757 studies,30 of which were retained.Results:Previous evidence is mostly provided by cross-sectional studies with survey data.In this study,evidence suggests that PSL is significantly associated with some types of healthcare utilization and health outcomes.In terms of healthcare utilization,findings indicate PSL is associated with an increase in the use of some preventive sendees and a decrease in the use of emergency care;while findings are mixed regarding associations of PSL with health provider visits and the use of mammograms and pap smears.As for health outcomes,findings suggest PSL is associated with improved mental and self-rated health,decreased incidence of influenza-like illness,and lower occupational injuries and mortality rates.Conclusion:PSL may be an effective tool in improving some healthcare utilization and health outcomes.Future research could help identify mechanisms through which PSL access works and identify what policy components lead to better outcomes.展开更多
Lodging is the most important constraint for soybean growth at seedling stage in maize-soybean relay strip intercropping system.In the field experiments,three soybean cultivars Nandou 032-4(shade susceptible cultivar;...Lodging is the most important constraint for soybean growth at seedling stage in maize-soybean relay strip intercropping system.In the field experiments,three soybean cultivars Nandou 032-4(shade susceptible cultivar; B1),Jiuyuehuang(moderately shade tolerant cultivar; B2),and Nandou 12(shade tolerant cultivar; B3) were used to evaluate the relationship between stem stress and lignin metabolism in the stem of soybean.Results showed that the intercropped soybean was in variable light condition throughout the day time and co-growth stage with maize.The xylem area and cross section ratio played a main role to form the stem stress.The B3 both in intercropping and monocropping expressed a high stem stress with higher xylem area,lignin content,and activity of enzymes(phenylalanine ammonia-lyase(PAL),4-coumarate: CoA ligase(4CL),cinnamyl alcohol dehydrogenase(CAD),and peroxidase(POD)) than those of B1 and B2.Among the soybean cultivars and planting pattern,lignin content was positively correlated with stem stress.However,a negative correlation was found between lignin content and actual rate of lodging.In conclusion,the shade tolerant soybean cultivar had larger xylem area,higher lignin content and activities of CAD,4CL,PAL,and POD than other soybean cultivars in intercropping.The lodging in maize-soybean intercropping can be minimized by planting shade tolerant and lodging resistant cultivar of soybean.The lignin content in stem could be a useful indicator for the evaluation of lodging resistance of soybean in intercropping and activities of enzymes were the key factors that influence the lignin biosynthesis.展开更多
Most lowlands in Northeast Thailand(Isaan region)are cultivated with rice and large areas are affected by salinity, which drastically limits rice production.A field experiment was conducted during the 2003 rainy seaso...Most lowlands in Northeast Thailand(Isaan region)are cultivated with rice and large areas are affected by salinity, which drastically limits rice production.A field experiment was conducted during the 2003 rainy season to explore the interactions between salinity and land management in two fields representative of two farming practices:an intensively managed plot with organic inputs and efficient water management,and one without organic matter addition.Field measurements,including pH,Eh,electrical conductivity(EC),and soil solution chemistry,were performed at three depths, with a particular focus on Fe dynamics,inside and outside saline patches. High reducing conditions appeared after flooding particularly in plots receiving organic matter and reduction processes leading to oxide reduction and to the release of Fe and,to a lesser extend,Mn to the soil solution.Oxide reduction led to the consumption of H^+ and the more the Fe reduction was,the higher the pH was,up to 6.5.Formation of hydroxy-green rust were likely to be at the origin of the pH stabilization.In the absence of organic amendments,high salinity prevented the establishment of the reduction processes and pH value remained around 4.Even under high reduction conditions,the Fe concentrations in the soil solution were below commonly observed toxic values and the amended plot had better rice production yield.展开更多
To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil ...To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil water conditions were controlled in greenhouse pot experiments using 2-year-old seedlings of Forsythia suspensa(Thunb.) Vahl. Photosynthetic gas exchange and chlorophyll fluorescence variables were measured and analyzed under 13 gradients of soil water content. Net photosynthetic rate(PN), stomatal conductance(gs), and water-use efficiency(WUE) in the seedlings exhibited a clear threshold response to the relative soil water content(RSWC). The highest PNand WUEoccurred at RSWCof51.84 and 64.10%, respectively. Both PNand WUEwere higher than the average levels at 39.79% B RSWCB 73.04%. When RSWCdecreased from 51.84 to 37.52%,PN, gs, and the intercellular CO2 concentration(Ci)markedly decreased with increasing drought stress; the corresponding stomatal limitation(Ls) substantially increased, and nonphotochemical quenching(NPQ) also tended to increase, indicating that within this range of soil water content, excessive excitation energy was dispersed from photosystem II(PSII) in the form of heat, and the reduction in PNwas primarily due to stomatal limitation.While RSWCdecreased below 37.52%, there were significant decreases in the maximal quantum yield of PSII photochemistry(Fv/Fm) and the effective quantum yield of PSII photochemistry(UPSII), photochemical quenching(qP), and NPQ; in contrast, minimal fluorescence yield of the dark-adapted state(F0) increased markedly. Thus,the major limiting factor for the PNreduction changed to a nonstomatal limitation due to PSII damage. Therefore, an RSWCof 37.52% is the maximum allowable water deficit for the normal growth of seedlings of F. suspensa, and a water content lower than this level should be avoided in field soil water management. Water contents should be maintained in the range of 39.79% B RSWCB 73.04% to ensure normal function of the photosynthetic apparatus and high levels of photosynthesis and efficiency in F.suspensa.展开更多
Tremendous advances in artificial intelligence(AI)in medical image analysis have been achieved in recent years.The integration of AI is expected to cause a revolution in various areas of medicine,including gastrointes...Tremendous advances in artificial intelligence(AI)in medical image analysis have been achieved in recent years.The integration of AI is expected to cause a revolution in various areas of medicine,including gastrointestinal(GI)pathology.Currently,deep learning algorithms have shown promising benefits in areas of diagnostic histopathology,such as tumor identification,classification,prognosis prediction,and biomarker/genetic alteration prediction.While AI cannot substitute pathologists,carefully constructed AI applications may increase workforce productivity and diagnostic accuracy in pathology practice.Regardless of these promising advances,unlike the areas of radiology or cardiology imaging,no histopathology-based AI application has been approved by a regulatory authority or for public reimbursement.Thus,implying that there are still some obstacles to be overcome before AI applications can be safely and effectively implemented in real-life pathology practice.The challenges have been identified at different stages of the development process,such as needs identification,data curation,model development,validation,regulation,modification of daily workflow,and cost-effectiveness balance.The aim of this review is to present challenges in the process of AI development,validation,and regulation that should be overcome for its implementation in real-life GI pathology practice.展开更多
A collection of 167 Thai and exotic rice accessions was subjected for evaluation of genetic diversity and assessment of relationship by simple sequence repeat (SSR) markers. Among a total of 49 SSR markers, 13 markers...A collection of 167 Thai and exotic rice accessions was subjected for evaluation of genetic diversity and assessment of relationship by simple sequence repeat (SSR) markers. Among a total of 49 SSR markers, 13 markers distributing over 12 rice chromosomes showed clear polymorphic band patterns, and they were selected for genetic assessment. A total of 110 alleles were detected with an average of 8.46 alleles per locus. The averages of gene diversity, heterozygosity and polymorphic information content were 0.59, 0.02 and 0.56, respectively. The unweighted-pair group method with arithmetic averages (UPGMA) clustering analysis was performed for genetic distance, and phylogenetic tree was constructed. The result showed that this rice collection was divided into two major groups, classified as japonica and indica subspecies. Within the japonica group, temperate japonica and tropical japonica subgroups can be clearly separated. Three-dimensional principal component analysis projection and model-based population structure analysis showed consistent clustering results with two major groups of UPGMA analysis, supporting the classification of japonica and indica subspecies. The indica allelic frequency was also investigated to provide an indicative guide for breeders to overcome the practical problems on sterility of inter-subspecies hybrid offspring. This rice collection and information obtained in this study will be useful for rice breeding programs.展开更多
With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic...With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic of various circles of society. In order to accelerate the poverty alleviation and provide references and recommendations for further development of theory and practice of financial poverty alleviation,this paper made an overview of the organization system,operation mechanism and service products of rural financial poverty alleviation,elaborated the development path of financial poverty alleviation,and came up with recommendations for financial poverty alleviation.展开更多
Oxy fuel combustion and conventional cycle(currently working cycle) in Kazeroon plant are modeled using commercial thermodynamic modeling software. Economic evaluation of the two models regarding the resources of tran...Oxy fuel combustion and conventional cycle(currently working cycle) in Kazeroon plant are modeled using commercial thermodynamic modeling software. Economic evaluation of the two models regarding the resources of transport and injection of carbon dioxide into oil fields at Gachsaran for enhanced oil recovery in the various oil price indices is conducted and indices net present value(NPV) and internal rate of return on investment(IRR) are calculated. The results of the two models reveal that gross efficiency of the oxy fuel cycle is more than reference cycle(62% compared to 49.03%), but the net efficiency is less(41.85% compared to 47.92%) because of the high-energy consumption of the components, particularly air separation unit(ASU) in the oxy fuel cycle. In this model, pure carbon dioxide with pressure of 20×105 Pa and purity of 96.84% was captured. NOX emissions also decrease by 4289.7 tons per year due to separation of nitrogen in ASU. In this model, none of the components of oxy fuel cycle is a major engineering challenge. With increasing oil price, economic justification of oxy fuel combustion model increases. With the price of oil at $ 80 per barrel in mind and $ 31 per ton fines for emissions of carbon dioxide in the atmosphere, IRR is the same for both models.展开更多
Discharging wastewater containing heavy metals of Cu, Pb, Zn and Cd into water bodies can cause toxicity in plants and aquatic animals and some of them will be unable to survive except algae. Wastewater treatment meth...Discharging wastewater containing heavy metals of Cu, Pb, Zn and Cd into water bodies can cause toxicity in plants and aquatic animals and some of them will be unable to survive except algae. Wastewater treatment method to remove heavy metal contaminants includes chemical precipitation, ion exchange, membrane, filtration, adsorption using activated carbon. However, these methods are either expensive or have other disadvantages such as high energy consumption and inefficiencies when existing heavy metals are at trace concentration. Biosorption using algae biomass can be an alternative method to eliminate heavy metals. The objective of the project is to investigate the capability of Marine Algae (MA) and Freshwater Algae (FA) bi-omass in adsorbing heavy metals of Cu, Pb, Zn and Cd from water medium using synthetic water and industrial water. MA and FA were obtained from the eastern coast of Pulau Ubin and local fish farm respectively. After being fully washed with deionised water, dried in a furnace for 105°C, they are grinded to pass 1 mm2 of siever. MA and FA were characterised using FTIR to determine their functional groups. An industrial water was collected from industrial discharge from metal fac-tories in northern side of Singapore. Effect of adsorption time, adsorbent concentra-tion, and pH were studied. The result showed that FA and MA had a higher capability in adsorbing a total metal of about 40 ppm level from an industrial water, or 4 times than synthetic water concentration, at the same adsorbent dosage of 50 mg. In con-clusion, the presence of various functional groups, hydroxyl, carboxylic and amine groups, in all MA and FA samples had enabled the algae biomass to adsorb heavy metals of Cu, Pb, Cd and Zn from synthetic and industrial water. Due to their bio-sorptive properties and fast adsorption capability, algae could be a potential method for cleaning up surface water or post-treatment of wastewater and minimise the cost of eutrophication.展开更多
Owing to the interactions among the complex terrain, bottom materials, and the complicate hydrodynam-ics, typhoon waves show special characteristics as big waves appeared at the high water level (HWL) and small wave...Owing to the interactions among the complex terrain, bottom materials, and the complicate hydrodynam-ics, typhoon waves show special characteristics as big waves appeared at the high water level (HWL) and small waves emerged at low and middle water levels (LWL and MWL) in radial sand ridges (RSR). It is as-sumed that the mud damping, sandy bed friction and wave breaking effects have a great influence on the typhoon wave propagation in this area. Under the low wave energy, a mud layer will form and transport into the shallow area, thus the mud damping effects dominate at the LWL and the MWL. And high Collins coef-ficient (c around 1) can be applied to computing the damping effects at the LWL and the MWL. But under the high wave energy, the bottom sediment will be stirred and suspended, and then the damping effects disappear at the HWL. Thus the varying Collins coefficient with the water level method (VCWL) is imple-mented into the SWAN to model the typhoon wave process in the Lanshayang Channel (LSYC) of the RSR, the observed wave data under “Winnie” (“9711”) typhoon was used as validation. The results show that the typhoon wave in the RSR area is able to be simulated by the VCWL method concisely, and a constant wave breaking coefficient (γ) equaling 0.78 is better for the RSR where wide tidal flats and gentle bed slopes exist.展开更多
Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were d...Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.展开更多
Mitochondrial degradation plays a vital role in seed deterioration.Novel markers were investigated based on a new method for quantifying maize seed deterioration during 12 months’storage under ambient(lab bench,~27℃...Mitochondrial degradation plays a vital role in seed deterioration.Novel markers were investigated based on a new method for quantifying maize seed deterioration during 12 months’storage under ambient(lab bench,~27℃ and 50-80%relative humidity(RH))or controlled((15±1)℃ and(50±5)%RH in bags with low oxygen permeability)conditions involving two techniques:1)fast ethanol assay and 2)quantitative RT-PCR(qPCR)with four mitochondrial-related genes in maize seed:alcohol dehydrogenase(ADH1),alternative oxidase(AOX1),cytochrome c oxidase(COXc),and ATPase.Ethanol production during imbibition and the expression of genes using the new method were compared to the results of two conventional methods:a germination test and an accelerated ageing test.The results showed that germination following ambient seed storage reduced significantly compared to the controlled conditions,especially at 9 months of storage.Ethanol production of maize seed measured by fast ethanol assay increased during storage.After 6 months,the mean(n=4)ethanol production from seed under ambient conditions was 400μg L^-1 which was higher than under the controlled conditions(240μg L^-1).Stored mRNA level of COXc and ATPase significantly decreased over time in ambient storage but were quite stable under the controlled conditions.Maize seed was also treated for artificial ageing at 42℃ in 100%RH for 12,24,and 48 h.At 24 h after treatment(HAT),maize seed produced significantly more headspace ethanol than at 12 HAT and more than the control(non-treated seed).The transcription level of ADH1 and ethanol production increased.The transcription level of COXc was directly related to the severity of the ageing treatment.In conclusion,a combination of fast ethanol assay and qPCR enhanced understanding of maize seed deterioration and provided new possibilities for the evaluation of seed storability based on transcriptional levels.展开更多
[Objective] The paper was to establish an affordable indoor virus inoculation and identification technology. [Method] Taking Tobacco Mosaic Virus (TMV) and Cucumber Mosaic Vires (CMV) of sweet (hot) pepper as th...[Objective] The paper was to establish an affordable indoor virus inoculation and identification technology. [Method] Taking Tobacco Mosaic Virus (TMV) and Cucumber Mosaic Vires (CMV) of sweet (hot) pepper as the sources of virus, an affordable indoor virus inoculation and identification technology was developed in the paper. [ Result] The suitable inoculation concentration of CMV was five to ten times, and the best seedling age for inoculation was five to six leav- es. Suitable inoculation concentration of TMV was 20 to 30 times, and the best seedling age for inoculation was three to six leaves. Single inoculation technology was mainly used for indoor virus inoculation and identification of sweet (hot) pepper, and complex inoculation technology could also be adopted with first, st inoculation of CMV and late inoculation of TMV. For mixed inoculation technology, CMV: TMV should be 1: 1. Complex inoculation and mix inoculation should base on the tech- nology of single inoculation. Disease resistant materials, AID1-W22-dg176, ABgl-W22-48123, AB91-DL-6428, HY031-2-8-1-6, BYT-4-1-3-6-8, JFG-2-1-2-6, JF8S-1-1-5-4-8 and I'502-1-1-3-5, were identified by this method. [ Conclusion] This research provided scientific basis for standardization of indoor inoculation of sweet (hot) pepper virus.展开更多
Smallholder dairy farming in Africa is classified into rural, peri-urban and urban systems. The major classification criterion is demographic. Dairy systems are extensively characterized, but not based on rigorous sta...Smallholder dairy farming in Africa is classified into rural, peri-urban and urban systems. The major classification criterion is demographic. Dairy systems are extensively characterized, but not based on rigorous statistical analyses. We validated this classification based on herd genetic structure and identify determinants of within-system variations, taking Ethiopia as a case study. Discriminant function analysis correctly classified 38% - 50.6% of the 360 sampled farms into the three systems. Multinomial logistic regression analysis showed that rural and peri-urban farmers were 1.26 (P < 0.1) to 1.45 (P < 0.001) times more likely to keep local and low grade crossbreds and fewer high grade crosses (P < 0.05;odds ratio = 2.35) than the urban farmers. In the rural system, proportion of high grade crosses declined and low grades increased over generations, whereas in urban system the reverse was observed. Access to breeding services and land resources significantly determined the adoption of crossbred dairy herd within systems. In conclusion, considering farms within systems as a uniform unit to target development interventions may not be appropriate and thus farm topologies and system specific determinants of farmers’ breeding strategies need to be considered to design and introduce appropriate breeding interventions.展开更多
This study aimed to investigate chlorophyll content and photosynthetic characteristics of 17 pepper inbred lines which were selected independently. The results showed that chlorophyll contents significantly varied amo...This study aimed to investigate chlorophyll content and photosynthetic characteristics of 17 pepper inbred lines which were selected independently. The results showed that chlorophyll contents significantly varied among different inbred lines. To be specific, chlorophyll content of No. 68 inbred line was significantly higher than that of other 14 inbred lines ; chlorophyll content of No. 55 inbred line was signifieandy lower than that of other 15 inbred lines. The chlorophyll content of various inbred lines showed a decreasing order of No. 68 〉 No. 47 〉 No. 66 〉 No. 62 〉 No. 63 〉 No. 60 〉 No. 61 〉 No. 64 〉 No. 56 〉 No. 67 〉 No. 65 〉 No. 48 〉 No. 59 〉 No. 58 〉 No. 57 〉 No. 69 〉 No. 55 ; the photosynthetic rate of various inbred lines showed a decreasing order of No. 68 〉 No. 57 〉 No. 60 〉 No. 48 〉 No. 58 〉 No. 47 〉 No. 62 〉 No. 63 〉 No. 64 〉 No. 65 ; the maximum photesynthetie rate of No. 65 inbred line was significantly lower than other seven inbred lines, while no signifi- cant difference was observed among other nine inbred lines.展开更多
基金supported by the National Comprehensive Agricultural Development Projects (152531188)
文摘The agro-pasturage ecotone in northern China is not only an important green ecosystem barrier but also an important economic belt. However, the extensive operation manner and harsh natural surroundings lead to the grassland degradation, low agricultural productivity and people living in poverty. In our study, the result has shown that the aboveground biomass and economic benefits of improved grassland, artificial perennial grassland and silage farmland have been increased greatly. Therefore, the development and construction of high-yield silage farmland and artificial perennial grassland in agro-pasturage ecotone not only increase the economic benefits but also protect the ecological environment.
文摘Identifying the factors affecting drinking water consumption is essential to the rational management of water resources and effective environment protection. In this study, the effects of the factors on rural drinking water demand were studied using the adaptive neuro-fuzzy inference system (ANFIS) and hybrid models, such as the ANFIS-genetic algorithm (GA), ANFIS-particle swarm optimization (PSO), and support vector machine (SVM)-simulated annealing (SA). The rural areas of Hamadan Province in Iran were selected for the case study. Five drinking water consumption factors were selected for the assessment according to the literature, data availability, and the characteristics of the study area (such as precipitation, relative humidity, temperature, the number of subscribers, and water price). The results showed that the standard errors of ANFIS, ANFIS-GA, ANFIS-PSO, and SVM-SA were 0.669, 0.619, 0.705, and 0.578, respectively. Therefore, the hybrid model SVM-SA outperformed other models. The sensitivity analysis showed that of the parameters affecting drinking water consumption, the number of subscribers significantly affected the water consumption rate, while the average temperature was the least significant factor. Water price was a factor that could be easily controlled, but it was always one of the least effective parameters due to the low water fee.
文摘Objective:Paid sick leave(PSL)laws mandate employers give workers paid time off when they are sick or injured.This current study aims to examine whether access to PSL is associated with healthcare utilization and health outcomes and to summarize the types of utilization and outcomes which have been reported to be associated with PSL.Methods:We conducted a rapid evidence review.Our search of seven databases,including Medline,Embase,PsycINFO,Cochrane Library,CINAHL,Scopus,and JSTOR,on September 21,2020,identified 757 studies,30 of which were retained.Results:Previous evidence is mostly provided by cross-sectional studies with survey data.In this study,evidence suggests that PSL is significantly associated with some types of healthcare utilization and health outcomes.In terms of healthcare utilization,findings indicate PSL is associated with an increase in the use of some preventive sendees and a decrease in the use of emergency care;while findings are mixed regarding associations of PSL with health provider visits and the use of mammograms and pap smears.As for health outcomes,findings suggest PSL is associated with improved mental and self-rated health,decreased incidence of influenza-like illness,and lower occupational injuries and mortality rates.Conclusion:PSL may be an effective tool in improving some healthcare utilization and health outcomes.Future research could help identify mechanisms through which PSL access works and identify what policy components lead to better outcomes.
基金the support of the National Key R&D Program of China (2018YFD1000905,2016YFD0300209)the National Natural Science Foundation of China (31671626)
文摘Lodging is the most important constraint for soybean growth at seedling stage in maize-soybean relay strip intercropping system.In the field experiments,three soybean cultivars Nandou 032-4(shade susceptible cultivar; B1),Jiuyuehuang(moderately shade tolerant cultivar; B2),and Nandou 12(shade tolerant cultivar; B3) were used to evaluate the relationship between stem stress and lignin metabolism in the stem of soybean.Results showed that the intercropped soybean was in variable light condition throughout the day time and co-growth stage with maize.The xylem area and cross section ratio played a main role to form the stem stress.The B3 both in intercropping and monocropping expressed a high stem stress with higher xylem area,lignin content,and activity of enzymes(phenylalanine ammonia-lyase(PAL),4-coumarate: CoA ligase(4CL),cinnamyl alcohol dehydrogenase(CAD),and peroxidase(POD)) than those of B1 and B2.Among the soybean cultivars and planting pattern,lignin content was positively correlated with stem stress.However,a negative correlation was found between lignin content and actual rate of lodging.In conclusion,the shade tolerant soybean cultivar had larger xylem area,higher lignin content and activities of CAD,4CL,PAL,and POD than other soybean cultivars in intercropping.The lodging in maize-soybean intercropping can be minimized by planting shade tolerant and lodging resistant cultivar of soybean.The lignin content in stem could be a useful indicator for the evaluation of lodging resistance of soybean in intercropping and activities of enzymes were the key factors that influence the lignin biosynthesis.
基金the French Ministry of Research under the ACI-FNS"ECCO-PNBC"project"Evaluation du r~■le des paramètres environnementaux et des activités bactériennes dans la dynamique du fer et du manganèse dans la rhizosphère des plantes:application aux sols de rizières"by the French Embassy in Bangkok.
文摘Most lowlands in Northeast Thailand(Isaan region)are cultivated with rice and large areas are affected by salinity, which drastically limits rice production.A field experiment was conducted during the 2003 rainy season to explore the interactions between salinity and land management in two fields representative of two farming practices:an intensively managed plot with organic inputs and efficient water management,and one without organic matter addition.Field measurements,including pH,Eh,electrical conductivity(EC),and soil solution chemistry,were performed at three depths, with a particular focus on Fe dynamics,inside and outside saline patches. High reducing conditions appeared after flooding particularly in plots receiving organic matter and reduction processes leading to oxide reduction and to the release of Fe and,to a lesser extend,Mn to the soil solution.Oxide reduction led to the consumption of H^+ and the more the Fe reduction was,the higher the pH was,up to 6.5.Formation of hydroxy-green rust were likely to be at the origin of the pH stabilization.In the absence of organic amendments,high salinity prevented the establishment of the reduction processes and pH value remained around 4.Even under high reduction conditions,the Fe concentrations in the soil solution were below commonly observed toxic values and the amended plot had better rice production yield.
基金supported by the National Natural Science Foundation of China(Nos.41621061,31500511)the Natural Science Foundation of Shandong Province of China(No.ZR2015CL044)
文摘To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil water conditions were controlled in greenhouse pot experiments using 2-year-old seedlings of Forsythia suspensa(Thunb.) Vahl. Photosynthetic gas exchange and chlorophyll fluorescence variables were measured and analyzed under 13 gradients of soil water content. Net photosynthetic rate(PN), stomatal conductance(gs), and water-use efficiency(WUE) in the seedlings exhibited a clear threshold response to the relative soil water content(RSWC). The highest PNand WUEoccurred at RSWCof51.84 and 64.10%, respectively. Both PNand WUEwere higher than the average levels at 39.79% B RSWCB 73.04%. When RSWCdecreased from 51.84 to 37.52%,PN, gs, and the intercellular CO2 concentration(Ci)markedly decreased with increasing drought stress; the corresponding stomatal limitation(Ls) substantially increased, and nonphotochemical quenching(NPQ) also tended to increase, indicating that within this range of soil water content, excessive excitation energy was dispersed from photosystem II(PSII) in the form of heat, and the reduction in PNwas primarily due to stomatal limitation.While RSWCdecreased below 37.52%, there were significant decreases in the maximal quantum yield of PSII photochemistry(Fv/Fm) and the effective quantum yield of PSII photochemistry(UPSII), photochemical quenching(qP), and NPQ; in contrast, minimal fluorescence yield of the dark-adapted state(F0) increased markedly. Thus,the major limiting factor for the PNreduction changed to a nonstomatal limitation due to PSII damage. Therefore, an RSWCof 37.52% is the maximum allowable water deficit for the normal growth of seedlings of F. suspensa, and a water content lower than this level should be avoided in field soil water management. Water contents should be maintained in the range of 39.79% B RSWCB 73.04% to ensure normal function of the photosynthetic apparatus and high levels of photosynthesis and efficiency in F.suspensa.
文摘Tremendous advances in artificial intelligence(AI)in medical image analysis have been achieved in recent years.The integration of AI is expected to cause a revolution in various areas of medicine,including gastrointestinal(GI)pathology.Currently,deep learning algorithms have shown promising benefits in areas of diagnostic histopathology,such as tumor identification,classification,prognosis prediction,and biomarker/genetic alteration prediction.While AI cannot substitute pathologists,carefully constructed AI applications may increase workforce productivity and diagnostic accuracy in pathology practice.Regardless of these promising advances,unlike the areas of radiology or cardiology imaging,no histopathology-based AI application has been approved by a regulatory authority or for public reimbursement.Thus,implying that there are still some obstacles to be overcome before AI applications can be safely and effectively implemented in real-life pathology practice.The challenges have been identified at different stages of the development process,such as needs identification,data curation,model development,validation,regulation,modification of daily workflow,and cost-effectiveness balance.The aim of this review is to present challenges in the process of AI development,validation,and regulation that should be overcome for its implementation in real-life GI pathology practice.
基金supported by the Center of Excellence on Agricultural Biotechnology,Science and Technology Postgraduate Education and Research Development Office,Office of Higher Education Commission,Ministry of Education(AG-BIO/PERDO-CHE)Agricultural Research Development Agency(ARDA)National Science and Technology Development Agency in Thailand
文摘A collection of 167 Thai and exotic rice accessions was subjected for evaluation of genetic diversity and assessment of relationship by simple sequence repeat (SSR) markers. Among a total of 49 SSR markers, 13 markers distributing over 12 rice chromosomes showed clear polymorphic band patterns, and they were selected for genetic assessment. A total of 110 alleles were detected with an average of 8.46 alleles per locus. The averages of gene diversity, heterozygosity and polymorphic information content were 0.59, 0.02 and 0.56, respectively. The unweighted-pair group method with arithmetic averages (UPGMA) clustering analysis was performed for genetic distance, and phylogenetic tree was constructed. The result showed that this rice collection was divided into two major groups, classified as japonica and indica subspecies. Within the japonica group, temperate japonica and tropical japonica subgroups can be clearly separated. Three-dimensional principal component analysis projection and model-based population structure analysis showed consistent clustering results with two major groups of UPGMA analysis, supporting the classification of japonica and indica subspecies. The indica allelic frequency was also investigated to provide an indicative guide for breeders to overcome the practical problems on sterility of inter-subspecies hybrid offspring. This rice collection and information obtained in this study will be useful for rice breeding programs.
基金Supported by Bidding Project for Social Science Foundation of Hebei Agricultural University in 2017(ZB201702)Key Project of Humanities and Social Science Foundation of Hebei Provincial Department of Education(ZD201713)Social Science Foundation Project of Hebei Agricultural University(SK201604)
文摘With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic of various circles of society. In order to accelerate the poverty alleviation and provide references and recommendations for further development of theory and practice of financial poverty alleviation,this paper made an overview of the organization system,operation mechanism and service products of rural financial poverty alleviation,elaborated the development path of financial poverty alleviation,and came up with recommendations for financial poverty alleviation.
文摘Oxy fuel combustion and conventional cycle(currently working cycle) in Kazeroon plant are modeled using commercial thermodynamic modeling software. Economic evaluation of the two models regarding the resources of transport and injection of carbon dioxide into oil fields at Gachsaran for enhanced oil recovery in the various oil price indices is conducted and indices net present value(NPV) and internal rate of return on investment(IRR) are calculated. The results of the two models reveal that gross efficiency of the oxy fuel cycle is more than reference cycle(62% compared to 49.03%), but the net efficiency is less(41.85% compared to 47.92%) because of the high-energy consumption of the components, particularly air separation unit(ASU) in the oxy fuel cycle. In this model, pure carbon dioxide with pressure of 20×105 Pa and purity of 96.84% was captured. NOX emissions also decrease by 4289.7 tons per year due to separation of nitrogen in ASU. In this model, none of the components of oxy fuel cycle is a major engineering challenge. With increasing oil price, economic justification of oxy fuel combustion model increases. With the price of oil at $ 80 per barrel in mind and $ 31 per ton fines for emissions of carbon dioxide in the atmosphere, IRR is the same for both models.
文摘Discharging wastewater containing heavy metals of Cu, Pb, Zn and Cd into water bodies can cause toxicity in plants and aquatic animals and some of them will be unable to survive except algae. Wastewater treatment method to remove heavy metal contaminants includes chemical precipitation, ion exchange, membrane, filtration, adsorption using activated carbon. However, these methods are either expensive or have other disadvantages such as high energy consumption and inefficiencies when existing heavy metals are at trace concentration. Biosorption using algae biomass can be an alternative method to eliminate heavy metals. The objective of the project is to investigate the capability of Marine Algae (MA) and Freshwater Algae (FA) bi-omass in adsorbing heavy metals of Cu, Pb, Zn and Cd from water medium using synthetic water and industrial water. MA and FA were obtained from the eastern coast of Pulau Ubin and local fish farm respectively. After being fully washed with deionised water, dried in a furnace for 105°C, they are grinded to pass 1 mm2 of siever. MA and FA were characterised using FTIR to determine their functional groups. An industrial water was collected from industrial discharge from metal fac-tories in northern side of Singapore. Effect of adsorption time, adsorbent concentra-tion, and pH were studied. The result showed that FA and MA had a higher capability in adsorbing a total metal of about 40 ppm level from an industrial water, or 4 times than synthetic water concentration, at the same adsorbent dosage of 50 mg. In con-clusion, the presence of various functional groups, hydroxyl, carboxylic and amine groups, in all MA and FA samples had enabled the algae biomass to adsorb heavy metals of Cu, Pb, Cd and Zn from synthetic and industrial water. Due to their bio-sorptive properties and fast adsorption capability, algae could be a potential method for cleaning up surface water or post-treatment of wastewater and minimise the cost of eutrophication.
基金The National High Technology Research and Development Program(863 Program)of China under contract No.2012AA112509the National Natural Science Fundation of China under contract No.41373112the Open Research Foundation from the State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing Hydraulic Research Institute under contract No.2012491311
文摘Owing to the interactions among the complex terrain, bottom materials, and the complicate hydrodynam-ics, typhoon waves show special characteristics as big waves appeared at the high water level (HWL) and small waves emerged at low and middle water levels (LWL and MWL) in radial sand ridges (RSR). It is as-sumed that the mud damping, sandy bed friction and wave breaking effects have a great influence on the typhoon wave propagation in this area. Under the low wave energy, a mud layer will form and transport into the shallow area, thus the mud damping effects dominate at the LWL and the MWL. And high Collins coef-ficient (c around 1) can be applied to computing the damping effects at the LWL and the MWL. But under the high wave energy, the bottom sediment will be stirred and suspended, and then the damping effects disappear at the HWL. Thus the varying Collins coefficient with the water level method (VCWL) is imple-mented into the SWAN to model the typhoon wave process in the Lanshayang Channel (LSYC) of the RSR, the observed wave data under “Winnie” (“9711”) typhoon was used as validation. The results show that the typhoon wave in the RSR area is able to be simulated by the VCWL method concisely, and a constant wave breaking coefficient (γ) equaling 0.78 is better for the RSR where wide tidal flats and gentle bed slopes exist.
文摘Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.
基金supported by a Kasetsart University Graduate Scholarship, from the Graduate School, Kasetsart University, Bangkok, Thailandpartially funded by the Thailand Research Fund (MRG5980180)the Center of Excellence on Agricultural Biotechnology, Science and Technology Postgraduate Education and Research Development Office, Office of Higher Education Commission, Ministry of Education, Thailand (AG-BIO/PERDO-CHE)
文摘Mitochondrial degradation plays a vital role in seed deterioration.Novel markers were investigated based on a new method for quantifying maize seed deterioration during 12 months’storage under ambient(lab bench,~27℃ and 50-80%relative humidity(RH))or controlled((15±1)℃ and(50±5)%RH in bags with low oxygen permeability)conditions involving two techniques:1)fast ethanol assay and 2)quantitative RT-PCR(qPCR)with four mitochondrial-related genes in maize seed:alcohol dehydrogenase(ADH1),alternative oxidase(AOX1),cytochrome c oxidase(COXc),and ATPase.Ethanol production during imbibition and the expression of genes using the new method were compared to the results of two conventional methods:a germination test and an accelerated ageing test.The results showed that germination following ambient seed storage reduced significantly compared to the controlled conditions,especially at 9 months of storage.Ethanol production of maize seed measured by fast ethanol assay increased during storage.After 6 months,the mean(n=4)ethanol production from seed under ambient conditions was 400μg L^-1 which was higher than under the controlled conditions(240μg L^-1).Stored mRNA level of COXc and ATPase significantly decreased over time in ambient storage but were quite stable under the controlled conditions.Maize seed was also treated for artificial ageing at 42℃ in 100%RH for 12,24,and 48 h.At 24 h after treatment(HAT),maize seed produced significantly more headspace ethanol than at 12 HAT and more than the control(non-treated seed).The transcription level of ADH1 and ethanol production increased.The transcription level of COXc was directly related to the severity of the ageing treatment.In conclusion,a combination of fast ethanol assay and qPCR enhanced understanding of maize seed deterioration and provided new possibilities for the evaluation of seed storability based on transcriptional levels.
基金Supported by National Science and Technology Support Program(2012BAD02B02-10)Shijiazhuang Experiment Station of National Staple Vegetable Industrial Technology System(CARS-25-G-05)+2 种基金Science and Technology Support Program of Hebei Province(11220102D-1)Project of Hebei Science and Technology Hall(11220701D)Youth Foundation of Hebei Academy of Agriculture and Forestry Sciences(A2012050302)
文摘[Objective] The paper was to establish an affordable indoor virus inoculation and identification technology. [Method] Taking Tobacco Mosaic Virus (TMV) and Cucumber Mosaic Vires (CMV) of sweet (hot) pepper as the sources of virus, an affordable indoor virus inoculation and identification technology was developed in the paper. [ Result] The suitable inoculation concentration of CMV was five to ten times, and the best seedling age for inoculation was five to six leav- es. Suitable inoculation concentration of TMV was 20 to 30 times, and the best seedling age for inoculation was three to six leaves. Single inoculation technology was mainly used for indoor virus inoculation and identification of sweet (hot) pepper, and complex inoculation technology could also be adopted with first, st inoculation of CMV and late inoculation of TMV. For mixed inoculation technology, CMV: TMV should be 1: 1. Complex inoculation and mix inoculation should base on the tech- nology of single inoculation. Disease resistant materials, AID1-W22-dg176, ABgl-W22-48123, AB91-DL-6428, HY031-2-8-1-6, BYT-4-1-3-6-8, JFG-2-1-2-6, JF8S-1-1-5-4-8 and I'502-1-1-3-5, were identified by this method. [ Conclusion] This research provided scientific basis for standardization of indoor inoculation of sweet (hot) pepper virus.
文摘Smallholder dairy farming in Africa is classified into rural, peri-urban and urban systems. The major classification criterion is demographic. Dairy systems are extensively characterized, but not based on rigorous statistical analyses. We validated this classification based on herd genetic structure and identify determinants of within-system variations, taking Ethiopia as a case study. Discriminant function analysis correctly classified 38% - 50.6% of the 360 sampled farms into the three systems. Multinomial logistic regression analysis showed that rural and peri-urban farmers were 1.26 (P < 0.1) to 1.45 (P < 0.001) times more likely to keep local and low grade crossbreds and fewer high grade crosses (P < 0.05;odds ratio = 2.35) than the urban farmers. In the rural system, proportion of high grade crosses declined and low grades increased over generations, whereas in urban system the reverse was observed. Access to breeding services and land resources significantly determined the adoption of crossbred dairy herd within systems. In conclusion, considering farms within systems as a uniform unit to target development interventions may not be appropriate and thus farm topologies and system specific determinants of farmers’ breeding strategies need to be considered to design and introduce appropriate breeding interventions.
基金Supported by vegetable Station of Ningxia Hui Autonomous Region
文摘This study aimed to investigate chlorophyll content and photosynthetic characteristics of 17 pepper inbred lines which were selected independently. The results showed that chlorophyll contents significantly varied among different inbred lines. To be specific, chlorophyll content of No. 68 inbred line was significantly higher than that of other 14 inbred lines ; chlorophyll content of No. 55 inbred line was signifieandy lower than that of other 15 inbred lines. The chlorophyll content of various inbred lines showed a decreasing order of No. 68 〉 No. 47 〉 No. 66 〉 No. 62 〉 No. 63 〉 No. 60 〉 No. 61 〉 No. 64 〉 No. 56 〉 No. 67 〉 No. 65 〉 No. 48 〉 No. 59 〉 No. 58 〉 No. 57 〉 No. 69 〉 No. 55 ; the photosynthetic rate of various inbred lines showed a decreasing order of No. 68 〉 No. 57 〉 No. 60 〉 No. 48 〉 No. 58 〉 No. 47 〉 No. 62 〉 No. 63 〉 No. 64 〉 No. 65 ; the maximum photesynthetie rate of No. 65 inbred line was significantly lower than other seven inbred lines, while no signifi- cant difference was observed among other nine inbred lines.