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1.
IEEE Trans Neural Netw Learn Syst ; 34(7): 3501-3515, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34637381

RESUMO

This article investigates the problem of relaxed exponential stabilization for coupled memristive neural networks (CMNNs) with connection fault and multiple delays via an optimized elastic event-triggered mechanism (OEEM). The connection fault of the two or some nodes can result in the connection fault of other nodes and cause iterative faults in the CMNNs. Therefore, the method of backup resources is considered to improve the fault-tolerant capability and survivability of the CMNNs. In order to improve the robustness of the event-triggered mechanism and enhance the ability of the event-triggered mechanism to process noise signals, the time-varying bounded noise threshold matrices, time-varying decreased exponential threshold functions, and adaptive functions are simultaneously introduced to design the OEEM. In addition, the appropriate Lyapunov-Krasovskii functionals (LKFs) with some improved delay-product-type terms are constructed, and the relaxed exponential stabilization and globally uniformly ultimately bounded (GUUB) conditions are derived for the CMNNs with connection fault and multiple delays by means of some inequality processing techniques. Finally, two numerical examples are provided to illustrate the effectiveness of the results.


Assuntos
Redes Neurais de Computação , Fatores de Tempo
2.
IEEE Trans Cybern ; 53(3): 1485-1498, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34495857

RESUMO

This article is concerned with the exponential synchronization of coupled memristive neural networks (CMNNs) with multiple mismatched parameters and topology-based probability impulsive mechanism (TPIM) on time scales. To begin with, a novel model is designed by taking into account three types of mismatched parameters, including: 1) mismatched dimensions; 2) mismatched connection weights; and 3) mismatched time-varying delays. Then, the method of auxiliary-state variables is adopted to deal with the novel model, which implies that the presented novel model can not only use any isolated system (regard as a node) in the coupled system to synchronize the states of CMNNs but also can use an external node, that is, not affiliated to the coupled system to synchronize the states of CMNNs. Moreover, the TPIM is first proposed to efficiently schedule information transmission over the network, possibly subject to a series of nonideal factors. The novel control protocol is more robust against these nonideal factors than the traditional impulsive control mechanism. By means of the Lyapunov-Krasovskii functional, robust analysis approach, and some inequality processing techniques, exponential synchronization conditions unifying the continuous-time and discrete-time systems are derived on the framework of time scales. Finally, a numerical example is provided to illustrate the effectiveness of the main results.

3.
J Agric Food Chem ; 69(4): 1206-1213, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33481586

RESUMO

Starch biosynthesis in cereal crops is a complex pathway regulated by multiple starch synthetic enzymes. Starch synthase IIa (SSIIa) is well-known to be one of the major starch synthases and is very important in amylopectin biosynthesis. It has significant effects on grain composition and kernel traits. However, there are few reports on the association of natural variation of SSIIa in barley and grain composition and characteristics. In this work, two SSIIa isoforms were first identified as SSIIaH and SSIIaL by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis, mass spectrometry, and Western blotting. Sequence analysis of the SSIIa gene demonstrated that a 33 bp insertion coding a peptide of APPSSVVPAKK caused different SSIIa, e.g., SSIIaH and SSIIaL. Based on this molecular difference, a polymerase chain reaction marker was developed, which could be used to screen different SSIIa genotypes easily. Kernel hardness of SSIIaL genotypes was significantly higher than that of SSIIaH Chinese barley cultivars. The proportion of SSIIaL genotypes was extremely low in Australian barley cultivars (5/24) and much higher in Tibetan hull-less barley cultivars (46/74), consistent with the end-use requirements of barley grain. This study provided new information in barley endosperm starch synthesis and indicated that it is valuable for choosing the preferred SSIIa genotype according to the end-use requirements.


Assuntos
Hordeum/enzimologia , Proteínas de Plantas/metabolismo , Sementes/química , Sintase do Amido/metabolismo , Sequência de Aminoácidos , Amilopectina/química , Amilopectina/metabolismo , Austrália , Hordeum/química , Hordeum/genética , Proteínas de Plantas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sementes/enzimologia , Sementes/genética , Amido/química , Amido/metabolismo , Sintase do Amido/genética
4.
IEEE Trans Neural Netw Learn Syst ; 32(1): 308-321, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32217485

RESUMO

This article investigates the problem of robust exponential stability of fuzzy switched memristive inertial neural networks (FSMINNs) with time-varying delays on mode-dependent destabilizing impulsive control protocol. The memristive model presented here is treated as a switched system rather than employing the theory of differential inclusion and set-value map. To optimize the robust exponentially stable process and reduce the cost of time, hybrid mode-dependent destabilizing impulsive and adaptive feedback controllers are simultaneously applied to stabilize FSMINNs. In the new model, the multiple impulsive effects exist between two switched modes, and the multiple switched effects may also occur between two impulsive instants. Based on switched analysis techniques, the Takagi-Sugeno (T-S) fuzzy method, and the average dwell time, extended robust exponential stability conditions are derived. Finally, simulation is provided to illustrate the effectiveness of the results.


Assuntos
Lógica Fuzzy , Redes Neurais de Computação , Algoritmos , Simulação por Computador , Retroalimentação , Modelos Teóricos
5.
J Food Sci ; 85(10): 3141-3149, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32857867

RESUMO

Hull-less barley (HLB), especially waxy HLB, contains many physiologically active ingredients; however, its poor processing performance and end-product quality are unfavorable. In this study, 80% waxy or normal HLB wholegrain flour (WGF) and 20% wheat flour were used for baking bread. The farinograph and pasting properties of composite powders, and the nutritional value, textural properties, and in vitro hydrolysis of resultant breads were evaluated. The addition of a high proportion of HLB WGFs significantly increased the nutritional value of breads, especially the ß-glucan contents of waxy HLB breads. The addition of HLB WGFs and a suitable amount of wheat gluten led to a lower degree of softening of HLB bread flours but improved its farinograph characteristics, such as higher water absorption rate, development time, stability time, and farinograph quality number. Although the sensory profiles of HLB breads were considerably lower than those of wheat bread, they still received a good overall acceptability from a panel of sensory evaluators. HLB breads, particularly the waxy types, exhibited higher hardness, gumminess, chewiness, and lower specific volume, glycemic index and equilibrium concentration in starch hydrolysis. After baking, the starch crystallinity of dough changed from A to V type, and the relative crystallinity decreased. Overall, waxy HLB breads had more nutritional value than normal HLB breads. Higher ß-glucan and total dietary fiber content in HLB might have a positive effect on the nutritional value of the resultant breads. However, high ß-glucan and total dietary fiber was also accompanied by a negative effect on the sensory quality and processing performance of the end product. PRACTICAL APPLICATION: The composite flour with 80 g hull-less barley wholegrain flour, 20 g wheat flour, and 30 g wheat gluten can be substituted in breadmaking. Compared to wheat bread, hull-less barley bread exhibited different but acceptable sensory properties and had more nutritional value, particularly the waxy one. Therefore, a high proportion of hull-less barley could be recommended for bread production.


Assuntos
Pão/análise , Farinha/análise , Manipulação de Alimentos/métodos , Hordeum/química , Amido/análise , Fibras na Dieta/análise , Digestão , Aditivos Alimentares/análise , Manipulação de Alimentos/instrumentação , Glutens/análise , Índice Glicêmico , Dureza , Humanos , Valor Nutritivo , Triticum/química
6.
Nat Commun ; 9(1): 5433, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30575759

RESUMO

Tibetan barley (Hordeum vulgare L., qingke) is the principal cereal cultivated on the Tibetan Plateau for at least 3,500 years, but its origin and domestication remain unclear. Here, based on deep-coverage whole-genome and published exome-capture resequencing data for a total of 437 accessions, we show that contemporary qingke is derived from eastern domesticated barley and it is introduced to southern Tibet most likely via north Pakistan, India, and Nepal between 4,500 and 3,500 years ago. The low genetic diversity of qingke suggests Tibet can be excluded as a center of origin or domestication for barley. The rapid decrease in genetic diversity from eastern domesticated barley to qingke can be explained by a founder effect from 4,500 to 2,000 years ago. The haplotypes of the five key domestication genes of barley support a feral or hybridization origin for Tibetan weedy barley and reject the hypothesis of native Tibetan wild barley.


Assuntos
Domesticação , Efeito Fundador , Genoma de Planta , Hordeum/genética , Filogeografia , Tibet
7.
Sci Rep ; 8(1): 14928, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297768

RESUMO

Powdery mildew is a fungal disease that represents a ubiquitous threat to crop plants. Transcriptomic and metabolomic analyses were used to identify molecular and physiological changes in Tibetan hulless barley in response to powdery mildew. There were 3418 genes and 405 metabolites differentially expressed between the complete resistance cultivar G7 and the sensitive cultivar Z13. Weighted gene coexpression network analysis was carried out, and the differentially expressed genes were enriched in five and four major network modules in G7 and Z13, respectively. Further analyses showed that phytohormones, photosynthesis, phenylpropanoid biosynthesis, and flavonoid biosynthesis pathways were altered during Qingke-Blumeria graminis (DC.) f.sp. hordei (Bgh) interaction. Comparative analyses showed a correspondence between gene expression and metabolite profiles, and the activated defenses resulted in changes of metabolites involved in plant defense response, such as phytohormones, lipids, flavone and flavonoids, phenolamides, and phenylpropanoids. This study enabled the identification of Bgh responsive genes and provided new insights into the dynamic physiological changes that occur in Qingke during response to powdery mildew. These findings greatly improve our understanding of the mechanisms of induced defense response in Qingke and will provide new clues for the development of resistant Tibetan hulless barley varieties.


Assuntos
Ascomicetos/fisiologia , Regulação da Expressão Gênica de Plantas , Hordeum/genética , Hordeum/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Resistência à Doença , Redes Reguladoras de Genes , Hordeum/metabolismo , Metaboloma , Metabolômica , Proteínas de Plantas/metabolismo , Tibet , Transcriptoma
8.
BMC Genet ; 18(1): 102, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29207956

RESUMO

BACKGROUND: Clarifying genetic diversity in a large germplasm resource plays important roles in experimental designs that provides flexible utility in fundamental research and breeding in crops. However, the work is limited due to small collections of barley that are insufficient representatives. RESULTS: In the present study, we collected 562 hulless barley (Hordeum vulgare L.) accessions with worldwide geographic origins and evaluated their genetic variability and relatedness based on 93 simple sequence repeat (SSR) markers. In an integrated analysis of the population structure, analysis of molecular variance (AMOVA) and pairwise F ST, the 562 barley accessions exhibited a strong stratification that allowed for them to be divided into two major subpopulations (p1 and p2) and an admixture subpopulation, with 93, 408 and 61 accessions, respectively. In a neutral test, considerable proportions of SSR alleles expressed the strong non-neutrality in specific subpopulations (44 and 37), which are probably responsible for population differentiation. To reduce the diversity redundancy in large barley collections, we delicately selected a core set of 200 barley accessions as a tradeoff between diversity and representativeness in an easily handled population. In comparing the 562 barley accessions, the core barley set accounted for 96.2% of allelic diversity and 93% to 95% of phenotypic variability, whereas it exhibited a significant enhancement in minor allelic frequencies, which probably benefit association mapping in the barley core set. CONCLUSIONS: The results provided additional insight into the genetic structure in a large barley germplasm resource, from which an easily manageable barley core set was identified, demonstrating the great potential for discovering key QTLs and ultimately facilitating barley breeding progress.


Assuntos
Hordeum/classificação , Hordeum/genética , Repetições de Microssatélites , Cruzamento , Variação Genética , Sementes
9.
Mitochondrial DNA B Resour ; 1(1): 430-431, 2016 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-33490399

RESUMO

Hulless barley (Hordeum vulgar L. var. nudum) is one of the staple foods for Tibetans and an important livestock feed in the Tibetan Plateau. We report the complete mitochondrial genome of Tibetan hulless barely. The complete mitochondrial genome size is 416,675 bp. Hulless barely mitochondrial genome encode 34 protein-coding genes, 19 tRNA genes and three rRNA genes. The mitochondrial genome has 50 forward and palindrome repeats totally. Nucleotide sequence of coding region takes over 13.60%, GC content is 44.33%. The maximum-likelihood (ML) phylogenetic tree based on 11 protein-coding genes common to seven plant mitochondrial genomes using Arabidopsis thaliana as out-group support that hulless barely is close to Triticum species.

10.
Proc Natl Acad Sci U S A ; 112(4): 1095-100, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25583503

RESUMO

The Tibetan hulless barley (Hordeum vulgare L. var. nudum), also called "Qingke" in Chinese and "Ne" in Tibetan, is the staple food for Tibetans and an important livestock feed in the Tibetan Plateau. The diploid nature and adaptation to diverse environments of the highland give it unique resources for genetic research and crop improvement. Here we produced a 3.89-Gb draft assembly of Tibetan hulless barley with 36,151 predicted protein-coding genes. Comparative analyses revealed the divergence times and synteny between barley and other representative Poaceae genomes. The expansion of the gene family related to stress responses was found in Tibetan hulless barley. Resequencing of 10 barley accessions uncovered high levels of genetic variation in Tibetan wild barley and genetic divergence between Tibetan and non-Tibetan barley genomes. Selective sweep analyses demonstrate adaptive correlations of genes under selection with extensive environmental variables. Our results not only construct a genomic framework for crop improvement but also provide evolutionary insights of highland adaptation of Tibetan hulless barley.


Assuntos
Aclimatação/fisiologia , Variação Genética/fisiologia , Genoma de Planta/fisiologia , Hordeum/genética , Sequência de Bases , Dados de Sequência Molecular , Tibet
11.
J Agric Food Chem ; 62(47): 11369-85, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25345815

RESUMO

Granule-bound starch synthase I (GBSS I) plays an important role in the synthesis of amylose and in the determination of starch properties in barley grains. Genomic DNAs for the Waxy gene encoding GBSS I protein were sequenced from 34 barley accessions or lines from Qinghai-Tibet plateau in China, to identify Waxy gene nucleotide variations and study the roles of polymorphic sites of the Waxy gene on expression levels of Waxy transcripts and GBSS I proteins and on resulting starch properties. A total of 116 DNA polymorphic sites were identified within the barley Waxy gene, which divided the studied accessions into 11 haplotypes. Among 33 nucleotide polymorphic sites in coding regions, 5 SNPs in three exons were found to play different roles on the expression level of the Waxy transcript and the GBSS I protein and on the amylose content and starch properties. One SNP G(3935)-to-T substitution in the 10th exon in the accession Z999 (HP II-2) caused a high expression level of the Waxy transcript and the GBSS I protein and the amylose free phenotype. The other SNP alteration was a C(2453)-to-T in the fifth exon in the accession Z1191 (HP I-5), which drastically reduced the expression level of the Waxy transcript and the GBSS I protein and, finally, produced the amylose free phenotype. Three SNPs in the seventh exon in the accession Z1337 (HP I-6) did not significantly change the level of Waxy transcript, the GBSS I protein, and starch properties, except obviously reducing the breakdown value of starch viscosity and extending the peak time. A total of 84 DNA polymorphic sites were found in the noncoding regions. A 403 bp deletion at 5'UTR in the accession Z1979 (HP I-3) had low transcript level, low GBSS I protein level, and low amylose content due to the deletion of cis-acting DNA regulatory elements. A 191 bp insertion and a 15 bp insertion in the first intron and second exons, respectively, may be closely related to a higher transcript level of the Waxy gene and significant differences in some starch properties of the Waxy I DNA group as compared to the Waxy II DNA group. This study indicates the specific variations of the Waxy gene have a great effect on amylose synthesis and starch properties of hull-less barley, which could be very useful to produce new barley with variable starch properties.


Assuntos
Regulação da Expressão Gênica de Plantas , Hordeum/química , Hordeum/genética , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Sintase do Amido/genética , Amido/química , Sequência de Aminoácidos , Amilose/análise , Sequência de Bases , China , Elementos de DNA Transponíveis , DNA de Plantas/genética , Eletroforese em Gel de Poliacrilamida , Haplótipos , Hordeum/classificação , Dados de Sequência Molecular , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Sintase do Amido/metabolismo
12.
PLoS One ; 9(5): e98144, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24871534

RESUMO

BACKGROUND: Hulless barley is attracting increasing attention due to its unique nutritional value and potential health benefits. However, the molecular biology of the barley grain development and nutrient storage are not well understood. Furthermore, the genetic potential of hulless barley has not been fully tapped for breeding. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we investigated the transcriptome features during hulless barley grain development. Using Illumina paired-end RNA-Sequencing, we generated two data sets of the developing grain transcriptomes from two hulless barley landraces. A total of 13.1 and 12.9 million paired-end reads with lengths of 90 bp were generated from the two varieties and were assembled to 48,863 and 45,788 unigenes, respectively. A combined dataset of 46,485 All-Unigenes were generated from two transcriptomes with an average length of 542 bp, and 36,278 among were annotated with gene descriptions, conserved protein domains or gene ontology terms. Furthermore, sequences and expression levels of genes related to the biosynthesis of storage reserve compounds (starch, protein, and ß-glucan) were analyzed, and their temporal and spatial patterns were deduced from the transcriptome data of cultivated barley Morex. CONCLUSIONS/SIGNIFICANCE: We established a sequences and functional annotation integrated database and examined the expression profiles of the developing grains of Tibetan hulless barley. The characterization of genes encoding storage proteins and enzymes of starch synthesis and (1-3;1-4)-ß-D-glucan synthesis provided an overview of changes in gene expression associated with grain nutrition and health properties. Furthermore, the characterization of these genes provides a gene reservoir, which helps in quality improvement of hulless barley.


Assuntos
Hordeum/crescimento & desenvolvimento , Hordeum/genética , Proteínas de Plantas/metabolismo , Transcriptoma/genética , Sequência de Bases , Perfilação da Expressão Gênica , Ontologia Genética , Hordeum/enzimologia , Hordeum/metabolismo , Anotação de Sequência Molecular , Dados de Sequência Molecular , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas de Armazenamento de Sementes/genética , Análise de Sequência de RNA , Especificidade da Espécie , Amido/biossíntese
13.
ScientificWorldJournal ; 2014: 594579, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25587568

RESUMO

Hulless barley is an important cereal crop worldwide, especially in Tibet of China. However, this crop is usually susceptible to powdery mildew caused by Blumeria graminis f. sp. hordei. In this study, we aimed to understand the functions and pathways of genes involved in the disease resistance by transcriptome sequencing of a Tibetan barley landrace with high resistance to powdery mildew. A total of 831 significant differentially expressed genes were found in the infected seedlings, covering 19 functions. Either "cell," "cell part," and "extracellular region" in the cellular component category or "binding" and "catalytic" in the category of molecular function as well as "metabolic process" and "cellular process" in the biological process category together demonstrated that these functions may be involved in the resistance to powdery mildew of the hulless barley. In addition, 330 KEGG pathways were found using BLASTx with an E-value cut-off of <10(-5). Among them, three pathways, namely, "photosynthesis," "plant-pathogen interaction," and "photosynthesis-antenna proteins" had significant matches in the database. Significant expressions of the three pathways were detected at 24 h, 48 h, and 96 h after infection, respectively. These results indicated a complex process of barley response to powdery mildew infection.


Assuntos
Ascomicetos/fisiologia , Resistência à Doença/imunologia , Hordeum/genética , Hordeum/microbiologia , Doenças das Plantas/imunologia , Análise de Sequência de RNA/métodos , Transcriptoma/genética , Bases de Dados Genéticas , Éxons/genética , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Hordeum/imunologia , Íntrons/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Tibet
14.
Ecohealth ; 5(2): 104-14, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18787914

RESUMO

Tibetan nomads in the Tibetan Autonomous Region of China have experienced profound transitions in recent decades with important implications for land use, livelihoods, and health development. The change from being traditional nomads to agropastoralists engaged in permanent agriculture, a sedentary village life (known as "sedentarization"), has been associated with a remarkable change in diet and lifestyle, decline in spatial mobility, increase in food production, and emerging infectious and noncommunicable diseases. The overarching response of the government has been to emphasize infrastructure and technological solutions. The local adaptation strategies of Tibetan nomads through maintaining balanced mobile herding, reindeer husbandry, as well as off-farm labor and trade could address both the cause of environmental degradation and improve the well-being of local people. Drawing on transdisciplinary, preliminary field work in Gangga Township of Dingri County in the foothills of Mt. Everest, we identify pertinent linkages between land use and health, and spatial and temporal mismatch of livelihoods and health care services, in the transition to sedentary village life. We suggest emerging imperatives in Ecohealth to help restore Tibetan livelihoods in transition to a sedentary lifestyle.


Assuntos
Ecossistema , Saúde Ambiental , Política Pública , Características de Residência , Mudança Social , Migrantes , Populações Vulneráveis/etnologia , Agricultura/tendências , Altitude , Criação de Animais Domésticos/tendências , Animais , China , Doença Crônica/epidemiologia , Clima , Saúde Ambiental/economia , Poluição Ambiental , Feminino , Transição Epidemiológica , Humanos , Infecções/etnologia , Masculino , Fatores Socioeconômicos , Tibet/epidemiologia , Tibet/etnologia
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