In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values w...In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values with a large numberof samples has been sought for long. In order to achieve the goal of obtaining meaningful results directly from raw data,we developed a robust and user-friendly software platform with a series of tools for analysis in association study withhigh efficiency. The platform has been well evaluated by several sets of real data.展开更多
Carcinoma of the stomach is still the second most common cause of cancer death worldwide, although the incidence and mortality have fallen dramatically over the last 50 years in many regions. The incidence of gastric ...Carcinoma of the stomach is still the second most common cause of cancer death worldwide, although the incidence and mortality have fallen dramatically over the last 50 years in many regions. The incidence of gastric cancer varies in different parts of the world and among various ethnic groups. Despite advances in diagnosis and treatment, the 5-year survival rate of stomach cancer is only 20 per cent. Stomach cancer can be classified into intestinal and diffuse types based on epidemiological and clinicopathological features. The etiology of gastric cancer is multifactorial and includes both dietary and nondietary factors. The major diet-related risk factors implicated in stomach cancer development include high content of nitrates and high salt intake. Accumulating evidence has implicated the role of Helicobacter pylori (H. pylori) infection in the pathogenesis of gastric cancer. The development of gastric cancer is a complex, multistep process involving multiple genetic and epigenetic alterations of oncogenes, tumor suppressor genes, DNA repair genes, cell cycle regulators, and signaling molecules. A plausible program for gastric cancer prevention involves intake of a balanced diet containing fruits and vegetables, improved sanitationand hygiene, screening and treatment of H. pylori infection, and follow-up of precancerous lesions. The fact that diet plays an important role in the etiology of gastric cancer offers scope for nutritional chemoprevention. Animal models have been extensively used to analyze the stepwise evolution of gastric carcinogenesis and to test dietary chemopreventive agents. Development of multitargeted preventive and therapeutic strategies for gastric cancer is a major challenge for the future.展开更多
The genetic transformation was achieved by pollen_mediated approach on maize ( Zea mays L.) inbred lines Tai 9101 and Zong 31. Plasmid DNA of pGLⅡ_RC_1 was mixed with fresh pollen of maize inbreds in sucrose ...The genetic transformation was achieved by pollen_mediated approach on maize ( Zea mays L.) inbred lines Tai 9101 and Zong 31. Plasmid DNA of pGLⅡ_RC_1 was mixed with fresh pollen of maize inbreds in sucrose solution. The pollens were treated by ultrasonication and collected, pollinated on silks of maize ears. Transformants were confirmed by dot blot hybridization, PCR amplification and PCR_Southern blot hybridization. The pollen_mediated transformation approach could circumvent the tedious tissue culture procedures like in particle bombardment and Agrobacterium infection, etc. This approach is simple, easy to operate, and could be widely used in practice.展开更多
Gastric cancer(GC) remains an important cause of cancer death worldwide with a high mortality rate due to the fact that the majority of GC cases are diagnosed at an advanced stage when the prognosis is poor and the tr...Gastric cancer(GC) remains an important cause of cancer death worldwide with a high mortality rate due to the fact that the majority of GC cases are diagnosed at an advanced stage when the prognosis is poor and the treatment options are limited. Unfortunately, the existing circulating biomarkers for GC diagnosis and prognosis display low sensitivity and specificity and the GC diagnosis is based only on the invasive procedures such as upper digestive endoscopy. There is a huge need for less invasive or non-invasive tests but also highly specific biomarkers in case of GC. Body fluids such as peripheral blood, urine or saliva,stomach wash/gastric juice could be a source of specific biomarkers, providing important data for screening and diagnosis in GC. This review summarized the recently discovered circulating molecules such as microRNAs, long non-coding RNAs, circular RNAs, which hold the promise to develop new strategies for early diagnosis of GC.展开更多
RAPD (random amplified polymorphic DNA) markers were generated from filaments of 15 Porphyra lines representing four important groups, P. yezoensis, P. haitanensis, P. katadai var. hemiphylla and P. olig...RAPD (random amplified polymorphic DNA) markers were generated from filaments of 15 Porphyra lines representing four important groups, P. yezoensis, P. haitanensis, P. katadai var. hemiphylla and P. oligospermatangia . Among the total 69 fragments generated by 6 selected primers (among 50 primers), 67 appeared to be polymorphic (97.1%). Cluster analysis based on the RAPD results was performed. The 15 Porphyra lines were divided into 3 groups. This result was consistent with that from taxonomy analysis. A DNA fingerprinting based on 8 bands amplified with OPN_02 and OPJ_18 was constructed and might be used in Porphyra variety identification. Five specific RAPD fragments of 5 Porphyra lines were isolated and cloned into pGEM_T easy vector. These five RAPD fragments may be useful in germplasm identification and property protection of Porphyra .展开更多
This letter proposes two algorithms: a novel Quantum Genetic Algorithm (QGA)based on the improvement of Han's Genetic Quantum Algorithm (GQA) and a new Blind Source Separation (BSS) method based on QGA and Indepen...This letter proposes two algorithms: a novel Quantum Genetic Algorithm (QGA)based on the improvement of Han's Genetic Quantum Algorithm (GQA) and a new Blind Source Separation (BSS) method based on QGA and Independent Component Analysis (ICA). The simulation result shows that the efficiency of the new BSS method is obviously higher than that of the Conventional Genetic Algorithm (CGA).展开更多
Pro-inflammatory cytokines are produced in the gastric mucosa by inflammatory cells activated by chronic Helicobacter pylori (H. pylori) infection. Polymorphisms of these cytokine genes are associated with individual ...Pro-inflammatory cytokines are produced in the gastric mucosa by inflammatory cells activated by chronic Helicobacter pylori (H. pylori) infection. Polymorphisms of these cytokine genes are associated with individual differences in gastric mucosal cytokine mRNA level, which result in differences in gastric mucosal inflammation, acid inhibition and gastroduodenal disease risk in response to H. pylori infection. Although polymorphisms of interleukin (IL)-1B, IL-1RN and TNF-A have been reported to relate well with gastric cancer and peptic ulcer risk, those of IL-2, IL-4, IL-6 and IL-8 genes are unclear. In combined analyses using data from previous studies, we found that the risk of gastric non-cardia cancer development was significantly associated with IL-4-168 C allele (OR: 0.81, 95% CI: 0.69-1.00) and IL-4-590 T allele carrier status (0.61, 0.53-0.73), and IL-6-174 G/G genotype (2<Abstract>Pro-inflammatory cytokines are produced in the gastric mucosa by inflammatory cells activated by chronic Helicobacter pylori (H. pylori) infection. Polymorphisms of these cytokine genes are associated with individual differences in gastric mucosal cytokine mRNA level, which result in differences in gastric mucosal inflammation, acid inhibition and gastroduodenal disease risk in response to H. pylori infection. Although polymorphisms of interleukin (IL)-1B, IL-1RN and TNF-A have been reported to relate well with gastric cancer and peptic ulcer risk, those of IL-2, IL-4, IL-6 and IL-8 genes are unclear. In combined analyses using data from previous stud- ies, we found that the risk of gastric non-cardia cancer development was significantly associated with IL-4-168 C allele (OR: 0.81, 95% CI: 0.69-1.00) and IL-4-590 T allele carrier status (0.61, 0.53-0.73), and IL-6-174 G/G genotype (2.02, 1.31-3.10). In peptic ulcer development, IL-2-330 G and IL-4-590 T allele carriers had a significantly decreased risk (0.37, 0.27-0.50 and 0.58, 0.34-0.99, respectively). Moreover, IL-2, IL-4, IL-6 and IL-8 gene genotypes prevalence differs am展开更多
Molecular and genetic characterizations of mutants have led to a better understanding of many developmental processes in the model system Arabidopsis thaliana. However, the leaf development that is specific to plants ...Molecular and genetic characterizations of mutants have led to a better understanding of many developmental processes in the model system Arabidopsis thaliana. However, the leaf development that is specific to plants has been little studied. With the aim of contributing to the genetic dissection of leaf development, we have performed a large-scare screening for mutants with abnormal leaves. Among a great number of leaf mutants we have generated by T-DNA and transposon tagging and ethylmethae sulfonate (EMS) mutagenesis, four independent mutant lines have been identified and studied genetically. Phenotypes of these mutant lines represent the defects of four novel nuclear genes designated LL1 (LOTUS LEAF 1), LL2 (LOTUS LEAF 2), URO (UPRIGHT ROSETTE), and EIL (ENVIRONT CONDITION INDUCED LESION). The phenotypic analysis indicates that these genes play important roles during leaf development. FOr the further genetic analysis of these genes and the map-based cloning of LL1 and LL2, we have mapped these genes to chromosome regions with an efficient and rapid mapping method.展开更多
Since whole-genome sequencing of many crops has been achieved,crop functional genomics studies have stepped into the big-data and high-throughput era.However,acquisition of large-scale phenotypic data has become one o...Since whole-genome sequencing of many crops has been achieved,crop functional genomics studies have stepped into the big-data and high-throughput era.However,acquisition of large-scale phenotypic data has become one of the major bottlenecks hindering crop breeding and functional genomics studies.Nevertheless,recent technological advances provide us potential solutions to relieve this bottleneck and to explore advanced methods for large-scale phenotyping data acquisition and processing in the coming years.In this article,we review the major progress on high-throughput phenotyping in controlled environments and field conditions as well as its use for post-harvest yield and quality assessment in the past decades.We then discuss the latest multi-omics research combining high-throughput phenotyping with genetic studies.Finally,we propose some conceptual challenges and provide our perspectives on how to bridge the phenotype-genotype gap.It is no doubt that accurate high-throughput phenotyping will accelerate plant genetic improvements and promote the next green revolution in crop breeding.展开更多
The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one str...The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one strain of V. riparia L. Genetic diversity among these grapes was investigated based on RAPD analysis. The screening of 280 decamer oligonucleotides allowed the selection of 20 primers used for the analysis. A total of 191 RAPD markers were produced from the 20 selected primers. Relationships among the 83 clones or accessions based on their genetic distances were clustered using unweighted pair_group method arithmetic average (UPGMA) analysis in a dendrogram. Twenty_two clusters which fortunately adapted to 22 grape species level were clearly resolved on the dendrogram. The 18 wild grape species native to China were grouped into ten subclusters. The largest distance was found between V. riparia L., V. vinifera L., interspecific hybrid ( V. vinifera L.× V. larbrusca L.) and the wild grapes native to China. Among the wild grapes native to China, the largest distance was found between V. hancockii Hance and the other wild species. V. qinlingensis P.C.He was the second. Large genetic variation occurred among the different flower_type clones in one species.展开更多
Drought is the most important environmental stress affecting agriculture worldwide. Exploiting yield potential and maintaining yield stability of crops in water-limited environments are urgent tasks that must be under...Drought is the most important environmental stress affecting agriculture worldwide. Exploiting yield potential and maintaining yield stability of crops in water-limited environments are urgent tasks that must be undertaken in order to guarantee food supply for the increasing world population. Tremendous efforts have been devoted to identifying key regulators in plant drought response through genetic, molecular, and biochemical studies using, in most cases, the model species Arabidopsis thaliana. However, only a small portion of these regulators have been explored as potential candidate genes for their application in the improvement of drought tolerance in crops. Based on biological functions, these genes can be classified into the following three categories： （1） stress-responsive transcriptional regulation （e.g. DREB1, AREB, NF-YB）; （2） post-transcriptional RNA or protein modifications such as phosphorylation/dephosphorylation （e.g. SnRK2, ABI1） and farnesylation （e.g. ERA1）; and （3） osomoprotectant metabolism or molecular chaperones （e.g. CspB）. While continuing down the path to discovery of new target genes, serious efforts are also focused on fine-tuning the expression of the known candidate genes for stress tolerance in specific temporal and spatial patterns to avoid negative effects in plant growth and development. These efforts are starting to bear fruit by showing yield improvements in several crops under a variety of water-deprivation conditions. As most such evaluations have been performed under controlled growth environments, a gap still remains between early success in the laboratory and the application of these techniques to the elite cultivars of staple crops in the field. Nevertheless, significant progress has been made in the identification of signaling pathways and master regulators for drought tolerance. The knowledge acquired will facilitate the genetic engineering of single or multiple targets and quantitative trait loci in key crops to create commercialrade cultiv展开更多
Complex adaptive systems （cas） - systems that involve many components that adapt or learn as they interact - are at the heart of important contemporary problems. The study of cas poses unique challenges： Some of ou...Complex adaptive systems （cas） - systems that involve many components that adapt or learn as they interact - are at the heart of important contemporary problems. The study of cas poses unique challenges： Some of our most powerful muthemutical tools, particularly methods involivng fixed points, attractors, and the like, are of limited help in understanding the development of cas. This paper suggests ways to modify research methods and tools, with an emphasis on the role of computer-based models, to increase our understanding of cas.展开更多
基金This work was supported by the Major State Basic Research Development program of Chinathe National High Technology Research and Development Program of China.
文摘In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values with a large numberof samples has been sought for long. In order to achieve the goal of obtaining meaningful results directly from raw data,we developed a robust and user-friendly software platform with a series of tools for analysis in association study withhigh efficiency. The platform has been well evaluated by several sets of real data.
基金Supported by A Grant from the Department of Biotechnology,New Delhi, India under the 7th FP of the Indo-EU Joint Collaborative Project on "FUNCFOOD"
文摘Carcinoma of the stomach is still the second most common cause of cancer death worldwide, although the incidence and mortality have fallen dramatically over the last 50 years in many regions. The incidence of gastric cancer varies in different parts of the world and among various ethnic groups. Despite advances in diagnosis and treatment, the 5-year survival rate of stomach cancer is only 20 per cent. Stomach cancer can be classified into intestinal and diffuse types based on epidemiological and clinicopathological features. The etiology of gastric cancer is multifactorial and includes both dietary and nondietary factors. The major diet-related risk factors implicated in stomach cancer development include high content of nitrates and high salt intake. Accumulating evidence has implicated the role of Helicobacter pylori (H. pylori) infection in the pathogenesis of gastric cancer. The development of gastric cancer is a complex, multistep process involving multiple genetic and epigenetic alterations of oncogenes, tumor suppressor genes, DNA repair genes, cell cycle regulators, and signaling molecules. A plausible program for gastric cancer prevention involves intake of a balanced diet containing fruits and vegetables, improved sanitationand hygiene, screening and treatment of H. pylori infection, and follow-up of precancerous lesions. The fact that diet plays an important role in the etiology of gastric cancer offers scope for nutritional chemoprevention. Animal models have been extensively used to analyze the stepwise evolution of gastric carcinogenesis and to test dietary chemopreventive agents. Development of multitargeted preventive and therapeutic strategies for gastric cancer is a major challenge for the future.
文摘The genetic transformation was achieved by pollen_mediated approach on maize ( Zea mays L.) inbred lines Tai 9101 and Zong 31. Plasmid DNA of pGLⅡ_RC_1 was mixed with fresh pollen of maize inbreds in sucrose solution. The pollens were treated by ultrasonication and collected, pollinated on silks of maize ears. Transformants were confirmed by dot blot hybridization, PCR amplification and PCR_Southern blot hybridization. The pollen_mediated transformation approach could circumvent the tedious tissue culture procedures like in particle bombardment and Agrobacterium infection, etc. This approach is simple, easy to operate, and could be widely used in practice.
基金Supported by a grant of the Romanian National Authority for Scientific Research and Innovation,CNCS-UEFISCDI,No.PN-Ⅲ-P4-ID-PCCF2016-0158(contract PCCF17/2018)within PNCDI Ⅲ
文摘Gastric cancer(GC) remains an important cause of cancer death worldwide with a high mortality rate due to the fact that the majority of GC cases are diagnosed at an advanced stage when the prognosis is poor and the treatment options are limited. Unfortunately, the existing circulating biomarkers for GC diagnosis and prognosis display low sensitivity and specificity and the GC diagnosis is based only on the invasive procedures such as upper digestive endoscopy. There is a huge need for less invasive or non-invasive tests but also highly specific biomarkers in case of GC. Body fluids such as peripheral blood, urine or saliva,stomach wash/gastric juice could be a source of specific biomarkers, providing important data for screening and diagnosis in GC. This review summarized the recently discovered circulating molecules such as microRNAs, long non-coding RNAs, circular RNAs, which hold the promise to develop new strategies for early diagnosis of GC.
文摘RAPD (random amplified polymorphic DNA) markers were generated from filaments of 15 Porphyra lines representing four important groups, P. yezoensis, P. haitanensis, P. katadai var. hemiphylla and P. oligospermatangia . Among the total 69 fragments generated by 6 selected primers (among 50 primers), 67 appeared to be polymorphic (97.1%). Cluster analysis based on the RAPD results was performed. The 15 Porphyra lines were divided into 3 groups. This result was consistent with that from taxonomy analysis. A DNA fingerprinting based on 8 bands amplified with OPN_02 and OPJ_18 was constructed and might be used in Porphyra variety identification. Five specific RAPD fragments of 5 Porphyra lines were isolated and cloned into pGEM_T easy vector. These five RAPD fragments may be useful in germplasm identification and property protection of Porphyra .
基金Supported by the National Natural Science Foundation of China (No.60171029)
文摘This letter proposes two algorithms: a novel Quantum Genetic Algorithm (QGA)based on the improvement of Han's Genetic Quantum Algorithm (GQA) and a new Blind Source Separation (BSS) method based on QGA and Independent Component Analysis (ICA). The simulation result shows that the efficiency of the new BSS method is obviously higher than that of the Conventional Genetic Algorithm (CGA).
文摘Pro-inflammatory cytokines are produced in the gastric mucosa by inflammatory cells activated by chronic Helicobacter pylori (H. pylori) infection. Polymorphisms of these cytokine genes are associated with individual differences in gastric mucosal cytokine mRNA level, which result in differences in gastric mucosal inflammation, acid inhibition and gastroduodenal disease risk in response to H. pylori infection. Although polymorphisms of interleukin (IL)-1B, IL-1RN and TNF-A have been reported to relate well with gastric cancer and peptic ulcer risk, those of IL-2, IL-4, IL-6 and IL-8 genes are unclear. In combined analyses using data from previous studies, we found that the risk of gastric non-cardia cancer development was significantly associated with IL-4-168 C allele (OR: 0.81, 95% CI: 0.69-1.00) and IL-4-590 T allele carrier status (0.61, 0.53-0.73), and IL-6-174 G/G genotype (2<Abstract>Pro-inflammatory cytokines are produced in the gastric mucosa by inflammatory cells activated by chronic Helicobacter pylori (H. pylori) infection. Polymorphisms of these cytokine genes are associated with individual differences in gastric mucosal cytokine mRNA level, which result in differences in gastric mucosal inflammation, acid inhibition and gastroduodenal disease risk in response to H. pylori infection. Although polymorphisms of interleukin (IL)-1B, IL-1RN and TNF-A have been reported to relate well with gastric cancer and peptic ulcer risk, those of IL-2, IL-4, IL-6 and IL-8 genes are unclear. In combined analyses using data from previous stud- ies, we found that the risk of gastric non-cardia cancer development was significantly associated with IL-4-168 C allele (OR: 0.81, 95% CI: 0.69-1.00) and IL-4-590 T allele carrier status (0.61, 0.53-0.73), and IL-6-174 G/G genotype (2.02, 1.31-3.10). In peptic ulcer development, IL-2-330 G and IL-4-590 T allele carriers had a significantly decreased risk (0.37, 0.27-0.50 and 0.58, 0.34-0.99, respectively). Moreover, IL-2, IL-4, IL-6 and IL-8 gene genotypes prevalence differs am
基金supported by a grant from the Chinese Academy of Sciences,KJ951-B1-604 and a National Distinguished Young Scholar Award to Hai HUANG.
文摘Molecular and genetic characterizations of mutants have led to a better understanding of many developmental processes in the model system Arabidopsis thaliana. However, the leaf development that is specific to plants has been little studied. With the aim of contributing to the genetic dissection of leaf development, we have performed a large-scare screening for mutants with abnormal leaves. Among a great number of leaf mutants we have generated by T-DNA and transposon tagging and ethylmethae sulfonate (EMS) mutagenesis, four independent mutant lines have been identified and studied genetically. Phenotypes of these mutant lines represent the defects of four novel nuclear genes designated LL1 (LOTUS LEAF 1), LL2 (LOTUS LEAF 2), URO (UPRIGHT ROSETTE), and EIL (ENVIRONT CONDITION INDUCED LESION). The phenotypic analysis indicates that these genes play important roles during leaf development. FOr the further genetic analysis of these genes and the map-based cloning of LL1 and LL2, we have mapped these genes to chromosome regions with an efficient and rapid mapping method.
基金the National Key Research and Development Program of China(2016YFD0100101-18,2016YFD0100103)the National Natural Science Foundation of China(31770397,21800305)+2 种基金the Fundamental Research Funds for the Central Universities(2662017PY058,2662017QD044)UK-China grant BBSRC(grant no.BB/R02118X/1)the National Institute of Food and Agriculture,U.S.Department of Agriculture,Hatch project(ALA014-1-16016).
文摘Since whole-genome sequencing of many crops has been achieved,crop functional genomics studies have stepped into the big-data and high-throughput era.However,acquisition of large-scale phenotypic data has become one of the major bottlenecks hindering crop breeding and functional genomics studies.Nevertheless,recent technological advances provide us potential solutions to relieve this bottleneck and to explore advanced methods for large-scale phenotyping data acquisition and processing in the coming years.In this article,we review the major progress on high-throughput phenotyping in controlled environments and field conditions as well as its use for post-harvest yield and quality assessment in the past decades.We then discuss the latest multi-omics research combining high-throughput phenotyping with genetic studies.Finally,we propose some conceptual challenges and provide our perspectives on how to bridge the phenotype-genotype gap.It is no doubt that accurate high-throughput phenotyping will accelerate plant genetic improvements and promote the next green revolution in crop breeding.
基金openfoundationofNationalKeyBiotechnologyLaboratoryforTropicalCropsHaikou China
文摘The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one strain of V. riparia L. Genetic diversity among these grapes was investigated based on RAPD analysis. The screening of 280 decamer oligonucleotides allowed the selection of 20 primers used for the analysis. A total of 191 RAPD markers were produced from the 20 selected primers. Relationships among the 83 clones or accessions based on their genetic distances were clustered using unweighted pair_group method arithmetic average (UPGMA) analysis in a dendrogram. Twenty_two clusters which fortunately adapted to 22 grape species level were clearly resolved on the dendrogram. The 18 wild grape species native to China were grouped into ten subclusters. The largest distance was found between V. riparia L., V. vinifera L., interspecific hybrid ( V. vinifera L.× V. larbrusca L.) and the wild grapes native to China. Among the wild grapes native to China, the largest distance was found between V. hancockii Hance and the other wild species. V. qinlingensis P.C.He was the second. Large genetic variation occurred among the different flower_type clones in one species.
文摘Drought is the most important environmental stress affecting agriculture worldwide. Exploiting yield potential and maintaining yield stability of crops in water-limited environments are urgent tasks that must be undertaken in order to guarantee food supply for the increasing world population. Tremendous efforts have been devoted to identifying key regulators in plant drought response through genetic, molecular, and biochemical studies using, in most cases, the model species Arabidopsis thaliana. However, only a small portion of these regulators have been explored as potential candidate genes for their application in the improvement of drought tolerance in crops. Based on biological functions, these genes can be classified into the following three categories： （1） stress-responsive transcriptional regulation （e.g. DREB1, AREB, NF-YB）; （2） post-transcriptional RNA or protein modifications such as phosphorylation/dephosphorylation （e.g. SnRK2, ABI1） and farnesylation （e.g. ERA1）; and （3） osomoprotectant metabolism or molecular chaperones （e.g. CspB）. While continuing down the path to discovery of new target genes, serious efforts are also focused on fine-tuning the expression of the known candidate genes for stress tolerance in specific temporal and spatial patterns to avoid negative effects in plant growth and development. These efforts are starting to bear fruit by showing yield improvements in several crops under a variety of water-deprivation conditions. As most such evaluations have been performed under controlled growth environments, a gap still remains between early success in the laboratory and the application of these techniques to the elite cultivars of staple crops in the field. Nevertheless, significant progress has been made in the identification of signaling pathways and master regulators for drought tolerance. The knowledge acquired will facilitate the genetic engineering of single or multiple targets and quantitative trait loci in key crops to create commercialrade cultiv
文摘Complex adaptive systems （cas） - systems that involve many components that adapt or learn as they interact - are at the heart of important contemporary problems. The study of cas poses unique challenges： Some of our most powerful muthemutical tools, particularly methods involivng fixed points, attractors, and the like, are of limited help in understanding the development of cas. This paper suggests ways to modify research methods and tools, with an emphasis on the role of computer-based models, to increase our understanding of cas.
