[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu...[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 as experimental materials,we preliminarily measured the dynamic changes of dry matter accumulation and moisture content with the days after pollination lasted,and investigated the effect of moisture content in kernels on mechanical harvesting of Zhengdan 958 and Liyu 16.[Results] During summer growing season,Zhengdan 958 and Liyu 16 became physiologically mature and suitable for harvesting at about 51 days after pollination,Xianyu 335 and Hongda 8 required 58 days to become physiologically mature and suitable for harvesting after pollination.At physiologically mature stage,the moisture contents in kernels of Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 were respectively 33.74%,28.86%,32.05% and 35.24%,respectively.Adopting mechanical harvesting at physiologically mature stage,the kernel loss rate of Zhengdan 958 and Liyu 16 was consistent with the range of mechanical operation index（kernel loss rate of 0.84%≤2%）,while the percentage of broken kernels did not accord with the range of mechanical operation index（kernel crashing rate of 10.12%≧1%）.The results indicate that Zhengdan 958 and Liyu 16 are not suitable for mechanical harvesting using full feeding combine havester.[Conclusion] This study provided theoretical basis for improving the maize harvest index under delayed harvesting.展开更多
Variation in weather conditions during grain filling has substantial effects on maize kernel weight(KW). The objective of this work was to characterize variation in KW with sowing date-associated weather conditions an...Variation in weather conditions during grain filling has substantial effects on maize kernel weight(KW). The objective of this work was to characterize variation in KW with sowing date-associated weather conditions and examine the relationship between KW, grain filling parameters, and weather factors. Maize was sown on eight sowing dates(SD) at 15–20-day intervals from mid-March to mid-July during 2012 and 2013 in the North China Plain. With sowing date delay, KW increased initially and later declined, and the greatest KW was obtained at SD6 in both years. The increased KW at SD6 was attributed mainly to kernel growth rate(Gmean), and effective grain-filling period(P). Variations in temperature and radiation were the primary factors that influenced KW and grain-filling parameters. When the effective cumulative temperature(AT) and radiation(Ra)during grain filling were 950 °C and 1005.4 MJ m-2, respectively, P and KW were greatest. High temperatures(daily maximum temperature [Tmax] > 30.2 °C) during grain filling under early sowing conditions, or low temperatures(daily minimum temperature [Tmin] < 20.7 °C) under late sowing conditions combined with high diurnal temperature range(Tmax-min> 7.1 °C) decreased kernel growth rate and ultimately final KW. When sowing was performed from May 25 through June 27, higher KW and yield of maize were obtained. We conclude that variations in environmental conditions(temperature and radiation) during grain filling markedly affect growth rate and duration of grain filling and eventually affect kernel weight and yield of maize.展开更多
Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenome...Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenomenon in subclasses,so that edge classes and outliers cannot be effectively dealt with and the modeling result is not satisfactory.In order to solve these problems,a new feature extraction method based on weighted kernel Fisher criterion is presented to improve the clustering accuracy,in which feature mapping is adopted to bring the edge classes and outliers closer to other normal subclasses.Furthermore,the classified data are used to develop a multiple model based on support vector machine.The proposed method is applied to a bisphenol A production process for prediction of the quality index.The simulation results demonstrate its ability in improving the data classification and the prediction performance of the soft sensor.展开更多
Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW...Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW. One is Baudin/AWCS276(BA) for which a linkage map was available. Several largeeffect QTL controlling KW were detected in this population. Another is Morex/AWCS276(MA). A linkage map with 5273 makers formed 1454 clusters, was constructed by the genotyping by sequence(GBS) data of 201 RILs from this population. A single marker was selected to represent each of the clusters and the linkage map constructed with these markers covers a total length of 1022.4 c M with an average interval of approximately 0.7 cM between loci. Three of the large-effect loci controlling KW(located on 2 HL, 6 HL,and 7 HL, respectively) identified from the BA population were also detected in the MA population under different environments. The locus on 6 HL was detected in each of the experiments conducted for both populations thus was selected for developing near isogenic lines(NILs). Apart from KW, the two isolines for each pair of the putative NILs obtained showed no significant difference for any of the morphological characteristics assessed. The average difference in KW between the isolines for all the NILs obtained was about 15% based on assessments under both glasshouse and field conditions. Taken advantage that high quality genome assemblies for both Morex and AWCS276 are available, we identified candidate genes underlying two of the three loci based on an orthologous analysis. The NILs developed and the candidate genes identified in this study should facilitate the cloning and functional analysis of genes regulating KW in barley.展开更多
When the attributes of unknown targets are not just numerical attributes,but hybrid attributes containing linguistic attributes,the existing recognition methods are not effective.In addition,it is more difficult to id...When the attributes of unknown targets are not just numerical attributes,but hybrid attributes containing linguistic attributes,the existing recognition methods are not effective.In addition,it is more difficult to identify the unknown targets densely distributed in the feature space,especially when there is interval overlap between attribute measurements of different target classes.To address these problems,a novel method based on intuitionistic fuzzy comprehensive evaluation model(IFCEM)is proposed.For numerical attributes,targets in the database are divided into individual classes and overlapping classes,and for linguistic attributes,continuous interval-valued linguistic term set(CIVLTS)is used to describe target characteristic.A cloud modelbased method and an area-based method are proposed to obtain intuitionistic fuzzy decision information of query target on numerical attributes and linguistic attributes respectively.An improved inverse weighted kernel fuzzy c-means(IWK-FCM)algorithm is proposed for solution of attribute weight vector.The possibility matrix is applied to determine the identity and category of query target.Finally,a case study composed of parameter sensitivity analysis,recognition accuracy analysis.and comparison with other methods,is taken to verify the superiority of the proposed method.展开更多
The objective of the current study is to investigate the effects of different stages of shading after anthesis on grain weight and quality of maize at cytology level. The shading experiments were conducted in the fiel...The objective of the current study is to investigate the effects of different stages of shading after anthesis on grain weight and quality of maize at cytology level. The shading experiments were conducted in the field from 2005 to 2006, with a common maize cultivar （TY2） as the experimental material. Plants were given stress using horizontal shading net and the light intensity was reduced by 55%. Field-grown maize plants were shaded at 1-14 d （S1）, 15-28 d （$2）, and 29-42 d （$3） after pollination, respectively. Control plants （SO） were grown under natural light. Grain weight, quality, endosperm cell proliferation, cob sugar content, and grain pedicel vascular bundle cross section area were measured. The ultrastructural changes of endosperm ceils and endosperm transfer cells were observed after pollination. The result indicated that the grain weight, starch content, endosperm cell number, and volume were declined after shading. On the contrary, the proportion of embryo and endosperm, protein content, and fat content in grain increased. Shading treatments significantly delayed the development of the starch granules and remarkably reduced the endosperm filling status. Among the three treatments, the number of the grain endosperm was the least under shading stress at 1-14 d after pollination. However, the volume of starch granules and the substantiation of endosperm under shading treatment at 15-28 d after pollination were the worst. Compared with the control （natural sunlight without shading）, the soluble sugar of maize cob increased significantly, while there was no obvious change in vascular structure of small cluster stalk. The number of protein body in maize endosperm was influenced markedly by low light at different stages after pollination. Low light decreased the volume of the grain endosperm transfer and the cell wall extensions of the basal transfer ceils became thinner and shorter under shading treatment than those of the control. Furthermore, the degree of connection and the capacity of the nutrient transport were decreased and the mitochondrion number of the transfer cell was reduced after shading. The change in grain quality after shading was observed due to increase in the proportion of embryo and endosperm. The morphology and functions in endosperm transfer cell and the shortage of energy restricted the nutrient transport greatly with shading at different stages, suggesting that an impeded flux may be one of the important reasons for the reduction of maize grain weight of maize grain at later growth stage under low light condition.展开更多
As a major abiotic stress,drought causes instability and deterioration of malt barley quality.There is distinct difference among barley cultivars in the responses of the main malt quality traits to drought stress.In t...As a major abiotic stress,drought causes instability and deterioration of malt barley quality.There is distinct difference among barley cultivars in the responses of the main malt quality traits to drought stress.In the previous study,we identified some Tibetan wild barley accessions with relatively less change of malt quality traits under drought.In this study,we examined the impact of drought stress during grain filling stage on grain weight and several important malt quality traits,including total protein content,β-glucan content,limit dextrinase activity,β-amylase activity,and protein fractions in four barley genotypes(two Tibetan wild accessions and two cultivars).Drought treatment reduced grain weight,β-glucan content,and increased total protein content,β-amylase activity.These changes differed among barley genotypes and treatments,and are closely associated with grain filling process and kernel weight.All the results indicated Tibetan wild barley had great potential for developing drought tolerant barley cultivars.Relatively stable kernel weight or filling process under water stress should be highlighted in malt barley breeding in order to reduce the effect of water stress on malt barley quality.展开更多
Ear morphological traits such as volume and shape are important features of maize and the quantitative associations among them can help understand kernel yield determination. 150 mature ears each of 4 maize cultivars ...Ear morphological traits such as volume and shape are important features of maize and the quantitative associations among them can help understand kernel yield determination. 150 mature ears each of 4 maize cultivars were collected from field experiments, and ear length(L), diameter(D), area(S) and volume(V) were recorded for individual ears, kernel weight per ear also recorded for a portion of the examined ears. Following principles of dimensional analysis, 8 theoretical equations of 3 sets,which relate ear higher dimensions to its length and diameter, were developed and parameterized and validated with the field observations. The 3 optimized equations showed that the shape of ears in maize can be featured with 3 dimensionless form factors, namely diameter-to-length ratio(c=D/L), areal form factor(b=S/L/D), and volumetric form factor(a=V/L/D/D). Statistically,all of them were significantly different among cultivars, and a's values varied from 0.582 to 0.612, and b's 0.839-0.868, and c's 0.242-0.308. Volumetric form factor and areal form factor could estimate precisely ear volume and area respectively, but diameter-to-length ratio was not suitable to estimate ear diameter by its length. Ear volume explained almost all variation of ear kernel weight and product L*D*D did the same substantially. Dimensional analysis proved to be promising in understanding relationship among morphological traits of ears in maize. Its application in crop researches should improve our knowledge of the physical properties of crop plants.展开更多
In this paper, using the kernel weight function, we obtain the parameter estimation of p-norm distribution in semi-parametric regression model, which is effective to decide the distribution of random errors. Under the...In this paper, using the kernel weight function, we obtain the parameter estimation of p-norm distribution in semi-parametric regression model, which is effective to decide the distribution of random errors. Under the assumption that the distribution of observations is unimodal and symmetry, this method can give the estimates of the parametric. Finally, two simulated adjustment problem are constructed to explain this method. The new method presented in this paper shows an effective way of solving the problem; the estimated values are nearer to their theoretical ones than those by least squares adjustment approach.展开更多
Grain number,one of the major determinants of yield in Triticeae crops,is largely determined by spikelet number and spike rachis node number(SRN).Here,we identified three quantitative trait loci(QTLs)for SRN using 145...Grain number,one of the major determinants of yield in Triticeae crops,is largely determined by spikelet number and spike rachis node number(SRN).Here,we identified three quantitative trait loci(QTLs)for SRN using 145 recombinant inbred lines derived from a barley R90/1815D cross.qSRN1,the major-effect QTL,was mapped to chromosome 2H and explained up to 38.77%of SRN variation.Map-based cloning revealed that qSRN1 encodes the RAWUL domain-containing protein HvSRN1.Further analysis revealed that two key SNPs in the HvSRN1 promoter region(-2 kb upstream of the transcription start site)affect the transcript level of HvSRN1 and contribute to variation in SRN.Similar to its orthologous proteins OsLAX2 and ZmBA2,HvSRN1 showed protein–protein interactions with HvLAX1,suggesting that the LAX2–LAX1 model for spike morphology regulation may be conserved in Poaceae crops.CRISPR-Cas9-induced HvSRN1 mutants showed reduced SRN but increased grain size and weight,demonstrating a trade-off effect.Our results shed light on the role of HvSRN1 variation in regulating the balance between grain number and weight in barley.展开更多
Let L =-△+V(x) be a Schrodinger operator, where △ is the Laplacian on R^n,while nonnegative potential V(x) belonging to the reverse Holder class. The aim of this paper is to give generalized weighted Morrey estimate...Let L =-△+V(x) be a Schrodinger operator, where △ is the Laplacian on R^n,while nonnegative potential V(x) belonging to the reverse Holder class. The aim of this paper is to give generalized weighted Morrey estimates for the boundedness of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators.Moreover, the boundedness of the commutator operators formed by BMO functions and Marcinkiewicz integrals with rough kernel associated with Schrodinger operators is discussed on the generalized weighted Morrey spaces. As its special cases, the corresponding results of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators have been deduced, respectively. Also, Marcinkiewicz integral operators, rough Hardy-Littlewood(H-L for short) maximal operators, Bochner-Riesz means and parametric Marcinkiewicz integral operators which satisfy the conditions of our main results can be considered as some examples.展开更多
String kernels are popular tools for analyzing protein sequence data and they have been successfully applied to many computational biology problems. The traditional string kernels assume that different substrings are ...String kernels are popular tools for analyzing protein sequence data and they have been successfully applied to many computational biology problems. The traditional string kernels assume that different substrings are independent. However, substrings can be highly correlated due to their substructure relationship or common physico-chemical properties. This paper proposes two kinds of weighted spectrum kernels： The correlation spectrum kernel and the AA spectrum kernel. We evMuate their performances by predicting glycan-binding proteins of 12 glycans. The results show that the correlation spectrum kernel and the AA spectrum kernel perform significantly better than the spectrum kernel for nearly all the 12 glycans. By comparing the predictive power of AA spectrum kernels constructed by different physico-chemical properties, the authors can also identify the physico- chemical properties which contributes the most to the glycan-protein binding. The results indicate that physico-chemical properties of amino acids in proteins play an important role in the mechanism of glycamprotein binding.展开更多
We obtain the explicit formulae for the harmonic Bergman kernels of Bn／{0} and Rn／Bn and study the connection between harmonic Bergman kernel and weighted harmonic Bergman kernel.We also get the explicit formula for...We obtain the explicit formulae for the harmonic Bergman kernels of Bn／{0} and Rn／Bn and study the connection between harmonic Bergman kernel and weighted harmonic Bergman kernel.We also get the explicit formula for the weighted harmonic Bergman kernel of Bn／{0} with the weight 1/｜x｜4.展开更多
This paper presents a method using support vector machine with polyspectral kernels for classification of individual transmitters.Then,the neighborhood-roughset-based weighted feature set is proposed.The experiments o...This paper presents a method using support vector machine with polyspectral kernels for classification of individual transmitters.Then,the neighborhood-roughset-based weighted feature set is proposed.The experiments of the algorithms mentioned above indicate that they have consistency,which raises a new weighted kernel.The experiment shows that better classification rate can be achieved.展开更多
In this article, we consider a semiparametric model for contrast function which is defined asthe conditional expected outcome difference under comparative treatments. The contrast function can be used to recommend tre...In this article, we consider a semiparametric model for contrast function which is defined asthe conditional expected outcome difference under comparative treatments. The contrast function can be used to recommend treatment for better average outcomes. Existing approachesmodel the contrast function either parametrically or nonparametrically. We believe our approachimproves interpretability over the non-parametric approach while enhancing robustness overthe parametric approach. Without explicit estimation of the nonparametric part of our model,we show that a kernel-based method can identify the parametric part up to a multiplying constant. Such identification suffices for treatment recommendation. Our method is also extendedto high-dimensional settings. We study the asymptotics of the resulting estimation procedure inboth low- and high-dimensional cases. We also evaluate our method in simulation studies andreal data analyses.展开更多
基金Supported by Supporting Program for Sci & Tech Research of China(2009BADA6B01)Natural Science Foundation of Anhui Province(090411017)~~
文摘[Objective] The aim of this study was to investigate the dry matter accumulation,moisture content in maize kernel and their influences on mechanical harvesting.[Methods] Using Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 as experimental materials,we preliminarily measured the dynamic changes of dry matter accumulation and moisture content with the days after pollination lasted,and investigated the effect of moisture content in kernels on mechanical harvesting of Zhengdan 958 and Liyu 16.[Results] During summer growing season,Zhengdan 958 and Liyu 16 became physiologically mature and suitable for harvesting at about 51 days after pollination,Xianyu 335 and Hongda 8 required 58 days to become physiologically mature and suitable for harvesting after pollination.At physiologically mature stage,the moisture contents in kernels of Zhengdan 958,Xianyu 335,Hongda 8 and Liyu 16 were respectively 33.74%,28.86%,32.05% and 35.24%,respectively.Adopting mechanical harvesting at physiologically mature stage,the kernel loss rate of Zhengdan 958 and Liyu 16 was consistent with the range of mechanical operation index（kernel loss rate of 0.84%≤2%）,while the percentage of broken kernels did not accord with the range of mechanical operation index（kernel crashing rate of 10.12%≧1%）.The results indicate that Zhengdan 958 and Liyu 16 are not suitable for mechanical harvesting using full feeding combine havester.[Conclusion] This study provided theoretical basis for improving the maize harvest index under delayed harvesting.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201203096)the National Key Technology R&D Program of China(Nos.2013BAD07B00 and 2013BAD08B00)the China Agriculture Research System(No.CARS-02)
文摘Variation in weather conditions during grain filling has substantial effects on maize kernel weight(KW). The objective of this work was to characterize variation in KW with sowing date-associated weather conditions and examine the relationship between KW, grain filling parameters, and weather factors. Maize was sown on eight sowing dates(SD) at 15–20-day intervals from mid-March to mid-July during 2012 and 2013 in the North China Plain. With sowing date delay, KW increased initially and later declined, and the greatest KW was obtained at SD6 in both years. The increased KW at SD6 was attributed mainly to kernel growth rate(Gmean), and effective grain-filling period(P). Variations in temperature and radiation were the primary factors that influenced KW and grain-filling parameters. When the effective cumulative temperature(AT) and radiation(Ra)during grain filling were 950 °C and 1005.4 MJ m-2, respectively, P and KW were greatest. High temperatures(daily maximum temperature [Tmax] > 30.2 °C) during grain filling under early sowing conditions, or low temperatures(daily minimum temperature [Tmin] < 20.7 °C) under late sowing conditions combined with high diurnal temperature range(Tmax-min> 7.1 °C) decreased kernel growth rate and ultimately final KW. When sowing was performed from May 25 through June 27, higher KW and yield of maize were obtained. We conclude that variations in environmental conditions(temperature and radiation) during grain filling markedly affect growth rate and duration of grain filling and eventually affect kernel weight and yield of maize.
基金Supported by the National Natural Science Foundation of China(61273070)the Foundation of Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenomenon in subclasses,so that edge classes and outliers cannot be effectively dealt with and the modeling result is not satisfactory.In order to solve these problems,a new feature extraction method based on weighted kernel Fisher criterion is presented to improve the clustering accuracy,in which feature mapping is adopted to bring the edge classes and outliers closer to other normal subclasses.Furthermore,the classified data are used to develop a multiple model based on support vector machine.The proposed method is applied to a bisphenol A production process for prediction of the quality index.The simulation results demonstrate its ability in improving the data classification and the prediction performance of the soft sensor.
基金supported by the National Natural Science Foundation of China(31771794)the National Key Research and Development Program of China(2017YFD0100900 and 2016YFD0101004)+1 种基金the Outstanding Youth Foundation of the Department of Science and Technology of Sichuan Province(2016JQ0040)the International Science&Technology Cooperation Program of the Bureau of Science and Technology of Chengdu China(2015DFA306002015-GH03-00008-HZ)。
文摘Kernel weight(KW), together with kernel number per unit area, determines yield of cereal crops. Here,two barley recombinant inbred lines(RILs) populations with a shared parent were used to identify loci controlling KW. One is Baudin/AWCS276(BA) for which a linkage map was available. Several largeeffect QTL controlling KW were detected in this population. Another is Morex/AWCS276(MA). A linkage map with 5273 makers formed 1454 clusters, was constructed by the genotyping by sequence(GBS) data of 201 RILs from this population. A single marker was selected to represent each of the clusters and the linkage map constructed with these markers covers a total length of 1022.4 c M with an average interval of approximately 0.7 cM between loci. Three of the large-effect loci controlling KW(located on 2 HL, 6 HL,and 7 HL, respectively) identified from the BA population were also detected in the MA population under different environments. The locus on 6 HL was detected in each of the experiments conducted for both populations thus was selected for developing near isogenic lines(NILs). Apart from KW, the two isolines for each pair of the putative NILs obtained showed no significant difference for any of the morphological characteristics assessed. The average difference in KW between the isolines for all the NILs obtained was about 15% based on assessments under both glasshouse and field conditions. Taken advantage that high quality genome assemblies for both Morex and AWCS276 are available, we identified candidate genes underlying two of the three loci based on an orthologous analysis. The NILs developed and the candidate genes identified in this study should facilitate the cloning and functional analysis of genes regulating KW in barley.
基金supported by the Youth Foundation of the National Science Foundation of China(62001503)the Excellent Youth Scholar of the National Defense Science and Technology Foundation of China(2017-JCJQ-ZQ-003)the Special Fund for Taishan Scholar Project(ts201712072).
文摘When the attributes of unknown targets are not just numerical attributes,but hybrid attributes containing linguistic attributes,the existing recognition methods are not effective.In addition,it is more difficult to identify the unknown targets densely distributed in the feature space,especially when there is interval overlap between attribute measurements of different target classes.To address these problems,a novel method based on intuitionistic fuzzy comprehensive evaluation model(IFCEM)is proposed.For numerical attributes,targets in the database are divided into individual classes and overlapping classes,and for linguistic attributes,continuous interval-valued linguistic term set(CIVLTS)is used to describe target characteristic.A cloud modelbased method and an area-based method are proposed to obtain intuitionistic fuzzy decision information of query target on numerical attributes and linguistic attributes respectively.An improved inverse weighted kernel fuzzy c-means(IWK-FCM)algorithm is proposed for solution of attribute weight vector.The possibility matrix is applied to determine the identity and category of query target.Finally,a case study composed of parameter sensitivity analysis,recognition accuracy analysis.and comparison with other methods,is taken to verify the superiority of the proposed method.
基金supported by the National Basic Research Program of China (973 Program,2006CB101700)the National Natural Science Foundation of China (30871476)the Opening Foundation of State Key Laboratory of Crop Biology, and the Shandong Agricultural University (2009KF07)
文摘The objective of the current study is to investigate the effects of different stages of shading after anthesis on grain weight and quality of maize at cytology level. The shading experiments were conducted in the field from 2005 to 2006, with a common maize cultivar （TY2） as the experimental material. Plants were given stress using horizontal shading net and the light intensity was reduced by 55%. Field-grown maize plants were shaded at 1-14 d （S1）, 15-28 d （$2）, and 29-42 d （$3） after pollination, respectively. Control plants （SO） were grown under natural light. Grain weight, quality, endosperm cell proliferation, cob sugar content, and grain pedicel vascular bundle cross section area were measured. The ultrastructural changes of endosperm ceils and endosperm transfer cells were observed after pollination. The result indicated that the grain weight, starch content, endosperm cell number, and volume were declined after shading. On the contrary, the proportion of embryo and endosperm, protein content, and fat content in grain increased. Shading treatments significantly delayed the development of the starch granules and remarkably reduced the endosperm filling status. Among the three treatments, the number of the grain endosperm was the least under shading stress at 1-14 d after pollination. However, the volume of starch granules and the substantiation of endosperm under shading treatment at 15-28 d after pollination were the worst. Compared with the control （natural sunlight without shading）, the soluble sugar of maize cob increased significantly, while there was no obvious change in vascular structure of small cluster stalk. The number of protein body in maize endosperm was influenced markedly by low light at different stages after pollination. Low light decreased the volume of the grain endosperm transfer and the cell wall extensions of the basal transfer ceils became thinner and shorter under shading treatment than those of the control. Furthermore, the degree of connection and the capacity of the nutrient transport were decreased and the mitochondrion number of the transfer cell was reduced after shading. The change in grain quality after shading was observed due to increase in the proportion of embryo and endosperm. The morphology and functions in endosperm transfer cell and the shortage of energy restricted the nutrient transport greatly with shading at different stages, suggesting that an impeded flux may be one of the important reasons for the reduction of maize grain weight of maize grain at later growth stage under low light condition.
基金supported by the National Natural Science Foundation of China(31620103912)the earmarked fund for China Agriculture Research System(CARS-05)the Jiangsu Collaborative Innovation Center for Modern Crop Production,China(JCIC-MCP)。
文摘As a major abiotic stress,drought causes instability and deterioration of malt barley quality.There is distinct difference among barley cultivars in the responses of the main malt quality traits to drought stress.In the previous study,we identified some Tibetan wild barley accessions with relatively less change of malt quality traits under drought.In this study,we examined the impact of drought stress during grain filling stage on grain weight and several important malt quality traits,including total protein content,β-glucan content,limit dextrinase activity,β-amylase activity,and protein fractions in four barley genotypes(two Tibetan wild accessions and two cultivars).Drought treatment reduced grain weight,β-glucan content,and increased total protein content,β-amylase activity.These changes differed among barley genotypes and treatments,and are closely associated with grain filling process and kernel weight.All the results indicated Tibetan wild barley had great potential for developing drought tolerant barley cultivars.Relatively stable kernel weight or filling process under water stress should be highlighted in malt barley breeding in order to reduce the effect of water stress on malt barley quality.
基金Supported by the National Natural Science Foundation of China(31271658)National Key Research and Development Program of China(2016YFD0300306)
文摘Ear morphological traits such as volume and shape are important features of maize and the quantitative associations among them can help understand kernel yield determination. 150 mature ears each of 4 maize cultivars were collected from field experiments, and ear length(L), diameter(D), area(S) and volume(V) were recorded for individual ears, kernel weight per ear also recorded for a portion of the examined ears. Following principles of dimensional analysis, 8 theoretical equations of 3 sets,which relate ear higher dimensions to its length and diameter, were developed and parameterized and validated with the field observations. The 3 optimized equations showed that the shape of ears in maize can be featured with 3 dimensionless form factors, namely diameter-to-length ratio(c=D/L), areal form factor(b=S/L/D), and volumetric form factor(a=V/L/D/D). Statistically,all of them were significantly different among cultivars, and a's values varied from 0.582 to 0.612, and b's 0.839-0.868, and c's 0.242-0.308. Volumetric form factor and areal form factor could estimate precisely ear volume and area respectively, but diameter-to-length ratio was not suitable to estimate ear diameter by its length. Ear volume explained almost all variation of ear kernel weight and product L*D*D did the same substantially. Dimensional analysis proved to be promising in understanding relationship among morphological traits of ears in maize. Its application in crop researches should improve our knowledge of the physical properties of crop plants.
文摘In this paper, using the kernel weight function, we obtain the parameter estimation of p-norm distribution in semi-parametric regression model, which is effective to decide the distribution of random errors. Under the assumption that the distribution of observations is unimodal and symmetry, this method can give the estimates of the parametric. Finally, two simulated adjustment problem are constructed to explain this method. The new method presented in this paper shows an effective way of solving the problem; the estimated values are nearer to their theoretical ones than those by least squares adjustment approach.
基金supported by the National Key R&D Program of China (2018YFD1000706)Hainan Yazhou Bay Seed Laboratory (B21Y10214)+1 种基金the National Natural Science Foundation of China (no.31771774)the Agricultural Science and Technology Innovation Program,and the China Agricultural Research System (CARS-05).
文摘Grain number,one of the major determinants of yield in Triticeae crops,is largely determined by spikelet number and spike rachis node number(SRN).Here,we identified three quantitative trait loci(QTLs)for SRN using 145 recombinant inbred lines derived from a barley R90/1815D cross.qSRN1,the major-effect QTL,was mapped to chromosome 2H and explained up to 38.77%of SRN variation.Map-based cloning revealed that qSRN1 encodes the RAWUL domain-containing protein HvSRN1.Further analysis revealed that two key SNPs in the HvSRN1 promoter region(-2 kb upstream of the transcription start site)affect the transcript level of HvSRN1 and contribute to variation in SRN.Similar to its orthologous proteins OsLAX2 and ZmBA2,HvSRN1 showed protein–protein interactions with HvLAX1,suggesting that the LAX2–LAX1 model for spike morphology regulation may be conserved in Poaceae crops.CRISPR-Cas9-induced HvSRN1 mutants showed reduced SRN but increased grain size and weight,demonstrating a trade-off effect.Our results shed light on the role of HvSRN1 variation in regulating the balance between grain number and weight in barley.
文摘Let L =-△+V(x) be a Schrodinger operator, where △ is the Laplacian on R^n,while nonnegative potential V(x) belonging to the reverse Holder class. The aim of this paper is to give generalized weighted Morrey estimates for the boundedness of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators.Moreover, the boundedness of the commutator operators formed by BMO functions and Marcinkiewicz integrals with rough kernel associated with Schrodinger operators is discussed on the generalized weighted Morrey spaces. As its special cases, the corresponding results of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators have been deduced, respectively. Also, Marcinkiewicz integral operators, rough Hardy-Littlewood(H-L for short) maximal operators, Bochner-Riesz means and parametric Marcinkiewicz integral operators which satisfy the conditions of our main results can be considered as some examples.
基金supported in part by Research Grants Council of Hong Kong under Grant No.17301214HKU CERG Grants+2 种基金Hung Hing Ying Physical Research Grantthe Research Funds of Renmin University of Chinathe National Natural Science Foundation of China under Grant Nos.11271144,11101382,11471256,and S201201009985
文摘String kernels are popular tools for analyzing protein sequence data and they have been successfully applied to many computational biology problems. The traditional string kernels assume that different substrings are independent. However, substrings can be highly correlated due to their substructure relationship or common physico-chemical properties. This paper proposes two kinds of weighted spectrum kernels： The correlation spectrum kernel and the AA spectrum kernel. We evMuate their performances by predicting glycan-binding proteins of 12 glycans. The results show that the correlation spectrum kernel and the AA spectrum kernel perform significantly better than the spectrum kernel for nearly all the 12 glycans. By comparing the predictive power of AA spectrum kernels constructed by different physico-chemical properties, the authors can also identify the physico- chemical properties which contributes the most to the glycan-protein binding. The results indicate that physico-chemical properties of amino acids in proteins play an important role in the mechanism of glycamprotein binding.
基金Supported by National Natural Science Foundation of China(Grant No.10401024)
文摘We obtain the explicit formulae for the harmonic Bergman kernels of Bn／{0} and Rn／Bn and study the connection between harmonic Bergman kernel and weighted harmonic Bergman kernel.We also get the explicit formula for the weighted harmonic Bergman kernel of Bn／{0} with the weight 1/｜x｜4.
基金This work was supported by the National High Technology Research and Development Program of China(Grant No.2009AA01Z430)the Natural Science Foundation of Beijing(No.9092009)the National Science and Technology Major Program(2009ZX03004-003-03).
文摘This paper presents a method using support vector machine with polyspectral kernels for classification of individual transmitters.Then,the neighborhood-roughset-based weighted feature set is proposed.The experiments of the algorithms mentioned above indicate that they have consistency,which raises a new weighted kernel.The experiment shows that better classification rate can be achieved.
基金This research was partially supported through a PatientCentered Outcomes Research Institute(PCORI)award[ME-1409-21219]The first and third authors’research was partially supported by the Chinese Ministry of Education 111 Project[B14019]+1 种基金the US National Science Foundation[grant number DMS-1305474][grant number DMS-1612873].
文摘In this article, we consider a semiparametric model for contrast function which is defined asthe conditional expected outcome difference under comparative treatments. The contrast function can be used to recommend treatment for better average outcomes. Existing approachesmodel the contrast function either parametrically or nonparametrically. We believe our approachimproves interpretability over the non-parametric approach while enhancing robustness overthe parametric approach. Without explicit estimation of the nonparametric part of our model,we show that a kernel-based method can identify the parametric part up to a multiplying constant. Such identification suffices for treatment recommendation. Our method is also extendedto high-dimensional settings. We study the asymptotics of the resulting estimation procedure inboth low- and high-dimensional cases. We also evaluate our method in simulation studies andreal data analyses.
