Despite the global decline in the severity of the coronavirus disease 2019 (COVID-19) cases, the disease stillrepresents a major concern to the relevant scientific and medical communities. The primary concern of drug ...Despite the global decline in the severity of the coronavirus disease 2019 (COVID-19) cases, the disease stillrepresents a major concern to the relevant scientific and medical communities. The primary concern of drug scientists,virologists, and other concerned specialists in this respect is to find ready-to-use suitable and potent anticoronaviraltherapies that are broadly effective against the different species/strains of the coronaviruses in general, not only againstthe current and previous coronaviruses (e.g., the recently-appeared severe acute respiratory syndrome coronavirus 2“SARS-CoV-2”), i.e., effective antiviral agents for treatment and/or prophylaxis of any coronaviral infections, includingthose of the coming ones from the next species and strains (if any). As an expert in this field, I tried, in this up-to-dateperspective “viewpoint” article, to evaluate the suitability and applicability of using the currently-availableanticoronaviral agents for the next coronavirus diseases (COVIDs) and coronaviral pandemics, highlighting the mostimportant general guidelines that should be considered in the next pandemics from the therapeutic points of view.展开更多
作为应用语言学的一个重要研究领域,ESP(English for Specific Purposes,特殊用途英语)理论近年来有了长足的发展。很多国内外的专家学者在探寻其理论价值的同时,积极寻找其跨学科研究的可能性与可行性。本篇文章在简要分析了ESP理论的...作为应用语言学的一个重要研究领域,ESP(English for Specific Purposes,特殊用途英语)理论近年来有了长足的发展。很多国内外的专家学者在探寻其理论价值的同时,积极寻找其跨学科研究的可能性与可行性。本篇文章在简要分析了ESP理论的形成和特点后,主要探讨了在ESP理论指导下外语专业复合型英语人才培养的模式,并在论证过程中提到了商务英语学科在培养复合型英语人才方面的重大作用。展开更多
To compare the heterosis levels among various groups of parental lines used extensively in China, identify foundational heterotic groups in parental pools and understand the relationship between genetic distance and h...To compare the heterosis levels among various groups of parental lines used extensively in China, identify foundational heterotic groups in parental pools and understand the relationship between genetic distance and heterosis performance, 16 parental lines with extensive genetic variation were selected from various sub-groups, and 39 hybrid combinations were generated and evaluated in Fujian and Hainan Provinces of China. The main results were as follows: (1) The 16 parental lines can be grouped into 7 sub-groups consisting of 1 maintainer sub-group and 6 restorer sub-groups; (2) Mean grain yield of the restorer lines was higher than that of the maintainer lines, and mean yield of parental lines was higher than that of the hybrid combinations; (3) The two best heterotic patterns were II-32A × G5 and II-32A × G6, moreover, the order of restorer sub-groups according to grain yield, from the highest to lowest, was G7, G6, G5, G4, G3 and G2; High specific combining ability values were observed for combinations of II-32A × G5, II-32A × G6 and Tianfeng A × G7; (4) Hybrid combinations derived from II-32A crossed with 13 restorer lines had higher yield trait values (mid-parent heterosis, better-parent heterosis, standard heterosis over check and specific combining ability) than any other combinations; (5) Genetic distance was positively correlated with panicle number, grain length and length-to-width ratio (P 〈 0.05) and negatively correlated with grain width, grain yield, seed-setting rate, as well as mid-parent heterosis, standard heterosis over check, and specific combining ability for grain yield (P 〈 0.01). These heterotic groups and patterns and their argonomic traits will provide useful information for future hybrid rice breeding programs.展开更多
The two most important activities in maize breeding are the development of inbred lines with high values of general combining ability(GCA)and specific combining ability(SCA),and the identification of hybrids with high...The two most important activities in maize breeding are the development of inbred lines with high values of general combining ability(GCA)and specific combining ability(SCA),and the identification of hybrids with high yield potentials.Genomic selection(GS)is a promising genomic tool to perform selection on the untested breeding material based on the genomic estimated breeding values estimated from the genomic prediction(GP).In this study,GP analyses were carried out to estimate the performance of hybrids,GCA,and SCA for grain yield(GY)in three maize line-by-tester trials,where all the material was phenotyped in 10 to 11 multiple-location trials and genotyped with a mid-density molecular marker platform.Results showed that the prediction abilities for the performance of hybrids ranged from 0.59 to0.81 across all trials in the model including the additive effect of lines and testers.In the model including both additive and non-additive effects,the prediction abilities for the performance of hybrids were improved and ranged from 0.64 to 0.86 across all trials.The prediction abilities of the GCA for GY were low,ranging between-0.14 and 0.13 across all trials in the model including only inbred lines;the prediction abilities of the GCA for GY were improved and ranged from 0.49 to 0.55 across all trials in the model including both inbred lines and testers,while the prediction abilities of the SCA for GY were negative across all trials.The prediction abilities for GY between testers varied from-0.66 to 0.82;the performance of hybrids between testers is difficult to predict.GS offers the opportunity to predict the performance of new hybrids and the GCA of new inbred lines based on the molecular marker information,the total breeding cost could be reduced dramatically by phenotyping fewer multiple-location trials.展开更多
With the application of hybrid wheat, lodging is becoming one of the major factors limiting high yield in its production. However,few studies have focused on combining ability and heterosis analysis of stem-related tr...With the application of hybrid wheat, lodging is becoming one of the major factors limiting high yield in its production. However,few studies have focused on combining ability and heterosis analysis of stem-related traits. In this study, 24 crosses were made according to NCII genetic design, using the three(photo-sensitive male sterile lines)×eight(restorer lines) incomplete diallel crosses. The length of basal second internode(LBSI) and breaking strength of basal second internode(BSBSI)as well as other stem-related traits were used to perform the principal component analysis(PCA), combining ability and heterosis analysis. The PCA results showed that the variables could be classified into two main factors, which were named as the positive factor(factor 1) and the negative factor(factor 2), and accounted for 52.3 and 33.2%, respectively, of the total variance in different variables, combined with the analysis for index weight indicated that the factor 1-related traits play positive roles in lodging resistance formation of hybrids. Combining ability variance analysis indicated that its genetic performance was mainly dominated by additive gene effects, and the hybrid combinations with higher lodging resistance can be selected by using of 14 GF6085(R1), 14 GF6343-2(R4), 14 GF6937(R6), 14 GF7433-1(R7), and BS1086(M3),which are with the features with lower general combining ability(GCA) effects of factor 2-related traits whereas higher GCA effects of factor 1-related traits. The heterosis analysis showed that the wide range of heterosis varied with the traits and combinations, and GCA or specific combining ability(SCA) effects of factor 1-related traits except wall thickness of basal second internode(WTBSI) were positively and closely related to the heterosis of lodging resistance. Generally, the correlation coefficients of heterosis to GCA effects of sterile lines(GCAm) of factor 1-related traits are significantly higher than that to GCA of restorer lines(GCAr) and SCA, combined with the higher GCAm variance values of factor 1-related traits compared to GCAr, the GCAm of factor 1-related traits should be particularly considered when breeding hybrid combinations.The heritability analysis showed that the narrow-sense heritability of the diameter of basal second internode(DBSI) and the center of gravity height(TCGH) were obviously lower(<60%) than other traits, suggesting that these two traits were suitable for selection in higher generation for parental breeding. These could provide a theoretical basis for parental breeding and heterosis utilization of lodging resistance.展开更多
A 3×3 complete diallel cross comprising three families of the clam Meretrix meretrix(P1, P2 and P3) was used to determine the combining ability of parental families and heterosis of F1 under indoor and openair ...A 3×3 complete diallel cross comprising three families of the clam Meretrix meretrix(P1, P2 and P3) was used to determine the combining ability of parental families and heterosis of F1 under indoor and openair environments for growth traits. Analysis of variance for shell length and whole body weight indicated highly significant cross effects, environment effects and the interaction of cross by environment. General combining ability(GCA) and specific combing ability exhibited great variation among crosses and between two environments. Pooled over environments, P2 was the top combiner among the three parental families for both traits studied. The cross of P1 and P3 had the highest SCA. Additionally, significant reciprocal effects were observed. For individual environment, about half of the crossbred combinations showed favorable Mid-parent heterosis(MPH)(〉1%) for the shell length and whole body weight. Our data has shown that non-additive genetic and reciprocal effects constituted the major sources of genetic variation for both shell length and whole body weight, which indicates that crossbreeding among selective families could further explore the heterotic effects.展开更多
A new lattice Boltzmann model for compressible perfect gas is proposed. The numerical example shows that it can be used to simulate shock wave and contact discontinuity. The results are comparable with those obtained ...A new lattice Boltzmann model for compressible perfect gas is proposed. The numerical example shows that it can be used to simulate shock wave and contact discontinuity. The results are comparable with those obtained by traditional methods. The ratio of specific heats gamma may be chosen according to the requirement of problems.展开更多
Dormancy indices of hulled and dehulled seeds were investigated by using 19 cytoplasmic male sterile (CMS) lines, 9 restorer lines and their 109 F1 hybrids of indica hybrid rice. The seeds of each F1 and the parents...Dormancy indices of hulled and dehulled seeds were investigated by using 19 cytoplasmic male sterile (CMS) lines, 9 restorer lines and their 109 F1 hybrids of indica hybrid rice. The seeds of each F1 and the parents were harvested on 35 days after flowering. Combining ability was analyzed in 25 combinations made by 5 CMS lines and 5 restorer lines (North Carolina II mating design). The seed dormancy index of F1 was positively and highly significantly correlated with those of their parents and mid-parent value. Out of the 109 combinations, 82 combinations showed mid-parent heterosis, and 43 heterobeltiosis. Seed dormancy indices of F1s and their parents declined dramatically in dehulled seeds compared with hulled seeds, indicating that the hull played an important role in seed dormancy. However, the trends were similar in hulled seeds and dehulled seeds in terms of relationships between the seed dormancy indicices in F1 and their parents. The influence of hull on seed dormancy mainly depended on F1 genotype, not on the hull from maternal parent. The variances of general combining ability (GCA) in female and male parents occupied 59.2% and 31.1% of total variance, respectively. The variance of specific combining ability (SCA) in combinations occupied 9.7% of total variance, indicating that gene additive effects were principal. Among the 5 CMS lines, II112A had the highest GCA effect for seed dormancy, followed by D62A. Among the 5 restorer lines, IRl12 had the highest GCA effect for seed dormancy, followed by 2786. These lines are elite parental materials for breeding F1 hybrid rice with stronger seed dormancy.展开更多
A study of combining ability for improving rice cooking quality was carried out via genotype plus genotype x environment (GGE) biplot. Four restorer lines and three male sterile lines were used to obtain F1 in a lin...A study of combining ability for improving rice cooking quality was carried out via genotype plus genotype x environment (GGE) biplot. Four restorer lines and three male sterile lines were used to obtain F1 in a line x tester trial at the Rice Research Institute, Amol, Iran in 2009. GGE biplot analysis showed that Neda and IR56 were the best general combiners for amylose content (AC), whereas Nemat and IR28 had the highest general combining ability (GCA) effects for gelatinization temperature (GT), and IR58 and IR59 showed the highest GCA effects in terms of gel consistency (GC). Meanwhile IR58 and IR59 showed large specific combining ability (SCA) effects for AC, while Neda and SA13 had high SCA effects for GT. Nemat and IR28 had large SCA effects for GC. Because intermediate levels ofAC, GT and GC are ideal, Nemat × IR59 was considered as the best possible cross. Based on these results, the GGE biplot showed good potential for identifying suitable parents, heterotic crosses and the best hybrids in line x tester data.展开更多
The teaching of English for Specific Purposes has been in existence for over 30 years,and has beenprominence for more than 20 years,and is still in the ascendant.ESP teaching accounts for a consider-able proportion of...The teaching of English for Specific Purposes has been in existence for over 30 years,and has beenprominence for more than 20 years,and is still in the ascendant.ESP teaching accounts for a consider-able proportion of the teaching of English as a foreign language in China.It is therefore necessary forus Chinese teacher s to know more about ESP.展开更多
Lycopene is a red pigment in tomato with purported antioxidant properties. As the amount of lycopene has been reported to differ in different colored tomatoes or even absent in non-red tomatoes, the objective of this ...Lycopene is a red pigment in tomato with purported antioxidant properties. As the amount of lycopene has been reported to differ in different colored tomatoes or even absent in non-red tomatoes, the objective of this study was to investigate the inheritance of lycopene content and the color parameters of hybrids using a 10 parent diallel excluding reciprocals. Parents differed in general combining ability (GCA) for lycopene and color parameters. “Chocolate Stripe” (purple and brown striped) had the highest lycopene content followed by NC 1CS (red colored with the crimson gene) with the best general combining ability among parental lines. Hybrids differed in lycopene content and color parameters across two summer and greenhouse experiments, with no interaction between experiments indicating that the lycopene content was consistent. Narrow-sense heritability for lycopene was only 9% whereas broad-sense heritability was estimated to be 25%. The order of dominance for lycopene content was found as purple-brown > red > blue > yellow > green. Heritability estimates for color parameters were close to those for lycopene. This information may be useful in developing specialty type tomatoes or increasing lycopene content in tomatoes.展开更多
The assessment of heterotic F1 combinations is a basic requisite for hybrid seed development. A set of 30 F1 hybrids along with their parental inbred lines were evaluated under both normal and water deficit conditions...The assessment of heterotic F1 combinations is a basic requisite for hybrid seed development. A set of 30 F1 hybrids along with their parental inbred lines were evaluated under both normal and water deficit conditions for various physiological and agronomic traits. Highly significant mean squares due to general combining ability, specific combining ability and reciprocal effect were observed for all traits under both water regimes. Components of variation exhibited greater estimates for GCA variance (б2g) than SCA variance (б2s) for majority of the traits under both normal and stress conditions depicting the predominant role of additive genetic component. Inbred lines NCIL-20-20, D-157 and OH-8 were found to be the best general combiner on the basis of performance regarding grain yield per plant under water deficit condition. The F1 combinations namely, NCIL-20-20 × D-109, NCIL-20-20 × OH-8 and D-157 × NCIL-20-20 were out-performers based on yield and yield attributes under water deficit conditions. On the basis of our results, we recommend these hybrids for further exploitation to assess their potential for commercial cultivation under water deficit condition.展开更多
Since the development of China's economy and the strengthening of globalization, China's international trade is increas-ingly thriving and the total volume of trade is growing as well. The country's demand...Since the development of China's economy and the strengthening of globalization, China's international trade is increas-ingly thriving and the total volume of trade is growing as well. The country's demand for bilingual trade talents is increasing at the same time. As the result, it is necessary to make the reform and corresponding adjustments according to the training objectives of Business English curriculum in order to cultivate job-oriented and interdisciplinary trade talents that can meet the needs of mod-ern commercial society.展开更多
Pre-harvest sprouting in wheat is the germination of seeds within the spikes when rains occur after or during grain ripening, which occurs commonly in the barani tract of Pakistan. Therefore, 10 cultivars and five adv...Pre-harvest sprouting in wheat is the germination of seeds within the spikes when rains occur after or during grain ripening, which occurs commonly in the barani tract of Pakistan. Therefore, 10 cultivars and five advanced lines of spring bread wheat were evaluated for pre-harvest sprouting resistance. After natural rainfall,seeds were immediately collected from the wet spikes and tested for germinating ability. Three different germination tests were applied to hand-threshed seed:(1) spikes threshed on the day of sampling and germination tested immediately,(2) spikes threshed on the day of sampling and germination tested 1 week later, and(3) spikes threshed 1 week after sampling and germination test immediately after threshing. Seeds and spikes kept for 1 week were place on blotting paper at room temperature.Cultivars BARS-09, 09 FJ17, Doukkala-12, NARC-09 and Ouassou-20 exhibited higher sprouting resistance while other genotypes were susceptible to pre-harvest sprouting in each of the three tests. A diallel crossing was conducted with six susceptible and two resistant genotypes to assess the genetic behavior of pre-harvest sprouting resistance.The combining ability(CA) demonstrated a higher proportion of additive genetic effects for sprouting resistance, because of higher variance of general and specific CA for both parameters under study. Doukkala-12 and BARS-09 showed increased pre-harvest sprouting resistance in their F1 descendants.展开更多
Improving budget transparency is imperative in establishing a modern government framework in China.Current research into budget transparency normally focuses on revealing budget information but overlooks the principle...Improving budget transparency is imperative in establishing a modern government framework in China.Current research into budget transparency normally focuses on revealing budget information but overlooks the principle of neutrality in budgeting,thus being of little use in promoting a democratic budgeting system.We believe that the issue of budget transparency goes beyond the boundaries of the budget but is also about a tax-sharing mechanism based on budget neutrality1.The core of transparent budgeting is an orderly,moderate,fair and just budgeting decision-making.In the public’s eye,a transparent budget must display fairness and justice.A fiscal mechanism with transparent budgeting should adhere to the rule of neutrality and display fairness and justice in its implementation.Neutral taxation and neutral budgeting systems are indispensible in a transparent budget:general expenditures are to be covered by general fiscal revenue and specific expenditures by specifically selected tax revenue.In this way,it will be easier to achieve orderly,moderate,transparent,fair and just government budget decisions.展开更多
This paper studies the allocative efficiency in a Moscarini (2005)-type equilibrium search environment with learning. It is shown that the stationary equilib- rium is efficient if and only if the Hosios condition ho...This paper studies the allocative efficiency in a Moscarini (2005)-type equilibrium search environment with learning. It is shown that the stationary equilib- rium is efficient if and only if the Hosios condition holds no matter whether learning is about finn-specific human capital or about general human capital. However, the stationary equilibrium can never be efficient if externalities exist from unemployment. In contrast, even with externalities, the stationary equilibrium can be efficient under some modified Hosios condition if there is no uncertainty (standard Mortensen and Pissarides (1994)-type equilibrium search environment). The key intuition is that the equilibrium can only be efficient if firm-worker matching is formed and terminated efficiently.展开更多
文摘Despite the global decline in the severity of the coronavirus disease 2019 (COVID-19) cases, the disease stillrepresents a major concern to the relevant scientific and medical communities. The primary concern of drug scientists,virologists, and other concerned specialists in this respect is to find ready-to-use suitable and potent anticoronaviraltherapies that are broadly effective against the different species/strains of the coronaviruses in general, not only againstthe current and previous coronaviruses (e.g., the recently-appeared severe acute respiratory syndrome coronavirus 2“SARS-CoV-2”), i.e., effective antiviral agents for treatment and/or prophylaxis of any coronaviral infections, includingthose of the coming ones from the next species and strains (if any). As an expert in this field, I tried, in this up-to-dateperspective “viewpoint” article, to evaluate the suitability and applicability of using the currently-availableanticoronaviral agents for the next coronavirus diseases (COVIDs) and coronaviral pandemics, highlighting the mostimportant general guidelines that should be considered in the next pandemics from the therapeutic points of view.
文摘作为应用语言学的一个重要研究领域,ESP(English for Specific Purposes,特殊用途英语)理论近年来有了长足的发展。很多国内外的专家学者在探寻其理论价值的同时,积极寻找其跨学科研究的可能性与可行性。本篇文章在简要分析了ESP理论的形成和特点后,主要探讨了在ESP理论指导下外语专业复合型英语人才培养的模式,并在论证过程中提到了商务英语学科在培养复合型英语人才方面的重大作用。
基金supported by grants from the Hi-Tech Research and Development(863)Program of China(Grant Nos.2014AA10A603 and 2014AA10A604)the Special Foundation of Non-Profit Research Institutes of Fujian Province,China(Grant No.2015R1021-8)
文摘To compare the heterosis levels among various groups of parental lines used extensively in China, identify foundational heterotic groups in parental pools and understand the relationship between genetic distance and heterosis performance, 16 parental lines with extensive genetic variation were selected from various sub-groups, and 39 hybrid combinations were generated and evaluated in Fujian and Hainan Provinces of China. The main results were as follows: (1) The 16 parental lines can be grouped into 7 sub-groups consisting of 1 maintainer sub-group and 6 restorer sub-groups; (2) Mean grain yield of the restorer lines was higher than that of the maintainer lines, and mean yield of parental lines was higher than that of the hybrid combinations; (3) The two best heterotic patterns were II-32A × G5 and II-32A × G6, moreover, the order of restorer sub-groups according to grain yield, from the highest to lowest, was G7, G6, G5, G4, G3 and G2; High specific combining ability values were observed for combinations of II-32A × G5, II-32A × G6 and Tianfeng A × G7; (4) Hybrid combinations derived from II-32A crossed with 13 restorer lines had higher yield trait values (mid-parent heterosis, better-parent heterosis, standard heterosis over check and specific combining ability) than any other combinations; (5) Genetic distance was positively correlated with panicle number, grain length and length-to-width ratio (P 〈 0.05) and negatively correlated with grain width, grain yield, seed-setting rate, as well as mid-parent heterosis, standard heterosis over check, and specific combining ability for grain yield (P 〈 0.01). These heterotic groups and patterns and their argonomic traits will provide useful information for future hybrid rice breeding programs.
基金financial support of the Shanghai Agriculture Applied Technology Development Program of China(Z20190101)the Harvest Plus Project+7 种基金the Genomic Opensource Breeding Informatics Initiative(GOBII)(OPP1093167)supported by the Bill&Melinda Gates Foundationthe CGIAR Research Program(CRP)on MAIZEW1&W2 support from the Governments of Australia,Belgium,Canada,China,France,India,Japan,Republic of Korea,Mexico,the Netherlands,New Zealand,Norway,Sweden,Switzerland,the United Kingdom,the United States,and the World Bankgrants from the National Key Research and Development Program of China(2016YFD0101803)the National Natural Science Foundation of China(31801442)Shenyang City Key Laboratory of Maize Genomic Selection,Liaoning Province Key Scientific and Technological Research and Development Project(2011208001)the CIMMYT-China Specialty Maize Research Center Project funded by the Shanghai Municipal Finance Bureau(KF201802)the Chinese Scholarship Council。
文摘The two most important activities in maize breeding are the development of inbred lines with high values of general combining ability(GCA)and specific combining ability(SCA),and the identification of hybrids with high yield potentials.Genomic selection(GS)is a promising genomic tool to perform selection on the untested breeding material based on the genomic estimated breeding values estimated from the genomic prediction(GP).In this study,GP analyses were carried out to estimate the performance of hybrids,GCA,and SCA for grain yield(GY)in three maize line-by-tester trials,where all the material was phenotyped in 10 to 11 multiple-location trials and genotyped with a mid-density molecular marker platform.Results showed that the prediction abilities for the performance of hybrids ranged from 0.59 to0.81 across all trials in the model including the additive effect of lines and testers.In the model including both additive and non-additive effects,the prediction abilities for the performance of hybrids were improved and ranged from 0.64 to 0.86 across all trials.The prediction abilities of the GCA for GY were low,ranging between-0.14 and 0.13 across all trials in the model including only inbred lines;the prediction abilities of the GCA for GY were improved and ranged from 0.49 to 0.55 across all trials in the model including both inbred lines and testers,while the prediction abilities of the SCA for GY were negative across all trials.The prediction abilities for GY between testers varied from-0.66 to 0.82;the performance of hybrids between testers is difficult to predict.GS offers the opportunity to predict the performance of new hybrids and the GCA of new inbred lines based on the molecular marker information,the total breeding cost could be reduced dramatically by phenotyping fewer multiple-location trials.
基金supported by the National Key R&D Program of China(2016YFD0101601)the Beijing Natural Science Foundation,China(6194035)the Training Programme Foundation for the Beijing Municipal Excellent Talents,China(2017000020060G130)。
文摘With the application of hybrid wheat, lodging is becoming one of the major factors limiting high yield in its production. However,few studies have focused on combining ability and heterosis analysis of stem-related traits. In this study, 24 crosses were made according to NCII genetic design, using the three(photo-sensitive male sterile lines)×eight(restorer lines) incomplete diallel crosses. The length of basal second internode(LBSI) and breaking strength of basal second internode(BSBSI)as well as other stem-related traits were used to perform the principal component analysis(PCA), combining ability and heterosis analysis. The PCA results showed that the variables could be classified into two main factors, which were named as the positive factor(factor 1) and the negative factor(factor 2), and accounted for 52.3 and 33.2%, respectively, of the total variance in different variables, combined with the analysis for index weight indicated that the factor 1-related traits play positive roles in lodging resistance formation of hybrids. Combining ability variance analysis indicated that its genetic performance was mainly dominated by additive gene effects, and the hybrid combinations with higher lodging resistance can be selected by using of 14 GF6085(R1), 14 GF6343-2(R4), 14 GF6937(R6), 14 GF7433-1(R7), and BS1086(M3),which are with the features with lower general combining ability(GCA) effects of factor 2-related traits whereas higher GCA effects of factor 1-related traits. The heterosis analysis showed that the wide range of heterosis varied with the traits and combinations, and GCA or specific combining ability(SCA) effects of factor 1-related traits except wall thickness of basal second internode(WTBSI) were positively and closely related to the heterosis of lodging resistance. Generally, the correlation coefficients of heterosis to GCA effects of sterile lines(GCAm) of factor 1-related traits are significantly higher than that to GCA of restorer lines(GCAr) and SCA, combined with the higher GCAm variance values of factor 1-related traits compared to GCAr, the GCAm of factor 1-related traits should be particularly considered when breeding hybrid combinations.The heritability analysis showed that the narrow-sense heritability of the diameter of basal second internode(DBSI) and the center of gravity height(TCGH) were obviously lower(<60%) than other traits, suggesting that these two traits were suitable for selection in higher generation for parental breeding. These could provide a theoretical basis for parental breeding and heterosis utilization of lodging resistance.
基金The National High-Tech R&D Program of China(863 Program)under contract No.2012AA10A410the Key Technologies R&D Program of Jiangsu Province under contract No.BE2011372
文摘A 3×3 complete diallel cross comprising three families of the clam Meretrix meretrix(P1, P2 and P3) was used to determine the combining ability of parental families and heterosis of F1 under indoor and openair environments for growth traits. Analysis of variance for shell length and whole body weight indicated highly significant cross effects, environment effects and the interaction of cross by environment. General combining ability(GCA) and specific combing ability exhibited great variation among crosses and between two environments. Pooled over environments, P2 was the top combiner among the three parental families for both traits studied. The cross of P1 and P3 had the highest SCA. Additionally, significant reciprocal effects were observed. For individual environment, about half of the crossbred combinations showed favorable Mid-parent heterosis(MPH)(〉1%) for the shell length and whole body weight. Our data has shown that non-additive genetic and reciprocal effects constituted the major sources of genetic variation for both shell length and whole body weight, which indicates that crossbreeding among selective families could further explore the heterotic effects.
基金The project supported by the National Natural Science Foundation of China
文摘A new lattice Boltzmann model for compressible perfect gas is proposed. The numerical example shows that it can be used to simulate shock wave and contact discontinuity. The results are comparable with those obtained by traditional methods. The ratio of specific heats gamma may be chosen according to the requirement of problems.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University of China (Grant No. IRT0432)
文摘Dormancy indices of hulled and dehulled seeds were investigated by using 19 cytoplasmic male sterile (CMS) lines, 9 restorer lines and their 109 F1 hybrids of indica hybrid rice. The seeds of each F1 and the parents were harvested on 35 days after flowering. Combining ability was analyzed in 25 combinations made by 5 CMS lines and 5 restorer lines (North Carolina II mating design). The seed dormancy index of F1 was positively and highly significantly correlated with those of their parents and mid-parent value. Out of the 109 combinations, 82 combinations showed mid-parent heterosis, and 43 heterobeltiosis. Seed dormancy indices of F1s and their parents declined dramatically in dehulled seeds compared with hulled seeds, indicating that the hull played an important role in seed dormancy. However, the trends were similar in hulled seeds and dehulled seeds in terms of relationships between the seed dormancy indicices in F1 and their parents. The influence of hull on seed dormancy mainly depended on F1 genotype, not on the hull from maternal parent. The variances of general combining ability (GCA) in female and male parents occupied 59.2% and 31.1% of total variance, respectively. The variance of specific combining ability (SCA) in combinations occupied 9.7% of total variance, indicating that gene additive effects were principal. Among the 5 CMS lines, II112A had the highest GCA effect for seed dormancy, followed by D62A. Among the 5 restorer lines, IRl12 had the highest GCA effect for seed dormancy, followed by 2786. These lines are elite parental materials for breeding F1 hybrid rice with stronger seed dormancy.
文摘A study of combining ability for improving rice cooking quality was carried out via genotype plus genotype x environment (GGE) biplot. Four restorer lines and three male sterile lines were used to obtain F1 in a line x tester trial at the Rice Research Institute, Amol, Iran in 2009. GGE biplot analysis showed that Neda and IR56 were the best general combiners for amylose content (AC), whereas Nemat and IR28 had the highest general combining ability (GCA) effects for gelatinization temperature (GT), and IR58 and IR59 showed the highest GCA effects in terms of gel consistency (GC). Meanwhile IR58 and IR59 showed large specific combining ability (SCA) effects for AC, while Neda and SA13 had high SCA effects for GT. Nemat and IR28 had large SCA effects for GC. Because intermediate levels ofAC, GT and GC are ideal, Nemat × IR59 was considered as the best possible cross. Based on these results, the GGE biplot showed good potential for identifying suitable parents, heterotic crosses and the best hybrids in line x tester data.
文摘The teaching of English for Specific Purposes has been in existence for over 30 years,and has beenprominence for more than 20 years,and is still in the ascendant.ESP teaching accounts for a consider-able proportion of the teaching of English as a foreign language in China.It is therefore necessary forus Chinese teacher s to know more about ESP.
文摘Lycopene is a red pigment in tomato with purported antioxidant properties. As the amount of lycopene has been reported to differ in different colored tomatoes or even absent in non-red tomatoes, the objective of this study was to investigate the inheritance of lycopene content and the color parameters of hybrids using a 10 parent diallel excluding reciprocals. Parents differed in general combining ability (GCA) for lycopene and color parameters. “Chocolate Stripe” (purple and brown striped) had the highest lycopene content followed by NC 1CS (red colored with the crimson gene) with the best general combining ability among parental lines. Hybrids differed in lycopene content and color parameters across two summer and greenhouse experiments, with no interaction between experiments indicating that the lycopene content was consistent. Narrow-sense heritability for lycopene was only 9% whereas broad-sense heritability was estimated to be 25%. The order of dominance for lycopene content was found as purple-brown > red > blue > yellow > green. Heritability estimates for color parameters were close to those for lycopene. This information may be useful in developing specialty type tomatoes or increasing lycopene content in tomatoes.
文摘The assessment of heterotic F1 combinations is a basic requisite for hybrid seed development. A set of 30 F1 hybrids along with their parental inbred lines were evaluated under both normal and water deficit conditions for various physiological and agronomic traits. Highly significant mean squares due to general combining ability, specific combining ability and reciprocal effect were observed for all traits under both water regimes. Components of variation exhibited greater estimates for GCA variance (б2g) than SCA variance (б2s) for majority of the traits under both normal and stress conditions depicting the predominant role of additive genetic component. Inbred lines NCIL-20-20, D-157 and OH-8 were found to be the best general combiner on the basis of performance regarding grain yield per plant under water deficit condition. The F1 combinations namely, NCIL-20-20 × D-109, NCIL-20-20 × OH-8 and D-157 × NCIL-20-20 were out-performers based on yield and yield attributes under water deficit conditions. On the basis of our results, we recommend these hybrids for further exploitation to assess their potential for commercial cultivation under water deficit condition.
文摘Since the development of China's economy and the strengthening of globalization, China's international trade is increas-ingly thriving and the total volume of trade is growing as well. The country's demand for bilingual trade talents is increasing at the same time. As the result, it is necessary to make the reform and corresponding adjustments according to the training objectives of Business English curriculum in order to cultivate job-oriented and interdisciplinary trade talents that can meet the needs of mod-ern commercial society.
基金supported by Government of Punjab, PakistanHigher Education Commission of Pakistan
文摘Pre-harvest sprouting in wheat is the germination of seeds within the spikes when rains occur after or during grain ripening, which occurs commonly in the barani tract of Pakistan. Therefore, 10 cultivars and five advanced lines of spring bread wheat were evaluated for pre-harvest sprouting resistance. After natural rainfall,seeds were immediately collected from the wet spikes and tested for germinating ability. Three different germination tests were applied to hand-threshed seed:(1) spikes threshed on the day of sampling and germination tested immediately,(2) spikes threshed on the day of sampling and germination tested 1 week later, and(3) spikes threshed 1 week after sampling and germination test immediately after threshing. Seeds and spikes kept for 1 week were place on blotting paper at room temperature.Cultivars BARS-09, 09 FJ17, Doukkala-12, NARC-09 and Ouassou-20 exhibited higher sprouting resistance while other genotypes were susceptible to pre-harvest sprouting in each of the three tests. A diallel crossing was conducted with six susceptible and two resistant genotypes to assess the genetic behavior of pre-harvest sprouting resistance.The combining ability(CA) demonstrated a higher proportion of additive genetic effects for sprouting resistance, because of higher variance of general and specific CA for both parameters under study. Doukkala-12 and BARS-09 showed increased pre-harvest sprouting resistance in their F1 descendants.
基金This research is a major project from Ministry of Education,“China’s Public Fiscal Risk Evaluation and Counter Measures”(No.10JZD0023).
文摘Improving budget transparency is imperative in establishing a modern government framework in China.Current research into budget transparency normally focuses on revealing budget information but overlooks the principle of neutrality in budgeting,thus being of little use in promoting a democratic budgeting system.We believe that the issue of budget transparency goes beyond the boundaries of the budget but is also about a tax-sharing mechanism based on budget neutrality1.The core of transparent budgeting is an orderly,moderate,fair and just budgeting decision-making.In the public’s eye,a transparent budget must display fairness and justice.A fiscal mechanism with transparent budgeting should adhere to the rule of neutrality and display fairness and justice in its implementation.Neutral taxation and neutral budgeting systems are indispensible in a transparent budget:general expenditures are to be covered by general fiscal revenue and specific expenditures by specifically selected tax revenue.In this way,it will be easier to achieve orderly,moderate,transparent,fair and just government budget decisions.
文摘This paper studies the allocative efficiency in a Moscarini (2005)-type equilibrium search environment with learning. It is shown that the stationary equilib- rium is efficient if and only if the Hosios condition holds no matter whether learning is about finn-specific human capital or about general human capital. However, the stationary equilibrium can never be efficient if externalities exist from unemployment. In contrast, even with externalities, the stationary equilibrium can be efficient under some modified Hosios condition if there is no uncertainty (standard Mortensen and Pissarides (1994)-type equilibrium search environment). The key intuition is that the equilibrium can only be efficient if firm-worker matching is formed and terminated efficiently.