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1.
Opt Express ; 31(13): 20941-20954, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381206

RESUMO

Metasurface has extraordinary capability in the wavefront manipulation of electromagnetic waves, which provides an effective method for meta-holographic technology. However, holographic technology mostly focuses on the generation of the single-plane image, which lacks a systematic design method to generate, store, and reconstruct multi-plane holographic images. In this paper, the Pancharatnam-Berry phase meta-atom is designed as electromagnetic controller with the characteristics of the full phase range and high reflection amplitude. Different from the single-plane holography method, a novel multi-plane retrieval algorithm is proposed for the computation of the phase distribution. The metasurface, containing only 24 × 24 (30 × 30) elements, can produce high-quality single-(double-) plane image(s) with fewer elements. Meanwhile, the implementation of the compressed sensing approach stores almost all the holographic image information under a 25% compression ratio and reconstructs the image by the compressed data. The experimental measurements of the samples are consistent with the theoretical and simulated results. This systematic scheme provides an innovative and effective way for designing miniaturized meta-devices to generate high-quality images, which relate to practical applications including high-density data storage, information security, and imaging.

2.
Phys Chem Chem Phys ; 25(43): 29690-29697, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37882700

RESUMO

With the advent of graphene, two-dimensional (2D) materials have emerged as promising candidates for next-generation electronic and optoelectronic applications. The most anticipated 2D materials have been synthesized and exploited for novel applications. Multilayered zinc chalcogenides (ZnX) are the best precursors for obtaining atomic layer two-dimensional materials by exfoliation. Therefore, we carry out a detailed density functional theory-based study to achieve an exfoliation process of ZnX non-van der Waals sheets by straining and provide a microscopic understanding of the ferroelectric, optic, and spin behaviors of ZnX systems and the corresponding self-healable two-dimensional ZnX devices. The results revealed that 2D ZnX sheets can be obtained when strain is 14% for ZnS and ZnSe, and the peak values of exfoliation energy have a similar order of magnitude to those of traditional 2D materials, indicating the possibility of obtaining 2D ZnX monolayers. For intrinsic 2D ferroelectric materials with in-plane electric polarization, the direction of ZnX sheets can be reversed using an electric field with an energy barrier of ∼0.175 eV per atom for ZnSe, offering a promising functional basis for their application in ferroelectric nanodevices. The first absorption of photons for polarization perpendicular to the monolayer plane occurs in a high energy range of photons, facilitating their application in LEDs. The spin splitting in non-centrosymmetric ZnX crystals exhibits a Rashba spin-texture according to first-principles calculations. The self-healable two-dimensional nanodevices have a smooth curve from -0.5 to 0.5 eV. This work indicates the potential value of non-van der Waals ZnX 2D materials for their application in photoelectric and spintronic nanodevices.

3.
Sensors (Basel) ; 23(12)2023 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-37420663

RESUMO

In order to improve the stability and economy of 4WID-4WIS (four-wheel independent drive-four-wheel independent steering) electric vehicles in trajectory tracking, this paper proposes a trajectory tracking coordinated control strategy considering energy consumption economy. First, a hierarchical chassis coordinated control architecture is designed, which includes target planning layer, and coordinated control layer. Then, the trajectory tracking control is decoupled based on the decentralized control structure. Expert PID and Model Predictive Control (MPC) are employed to realize longitudinal velocity tracking and lateral path tracking, respectively, which calculate generalized forces and moments. In addition, with the objective of optimal overall efficiency, the optimal torque distribution for each wheel is achieved using the Mutant Particle Swarm Optimization (MPSO) algorithm. Additionally, the modified Ackermann theory is used to distribute wheel angles. Finally, the control strategy is simulated and verified using Simulink. Comparing the control results of the average distribution strategy and the wheel load distribution strategy, it can be concluded that the proposed coordinated control not only provides good trajectory tracking but also greatly improves the overall efficiency of the motor operating points, which enhances the energy economy and realizes the multi-objective coordinated control of the chassis.


Assuntos
Algoritmos , Fenômenos Fisiológicos , Eletricidade , Fenômenos Físicos , Registros
4.
Sensors (Basel) ; 21(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200363

RESUMO

In the process of vehicle chassis electrification, different active actuators and systems have been developed and commercialized for improved vehicle dynamic performances. For a vehicle system with actuation redundancy, the integration of individual chassis control systems can provide additional benefits compared to a single ABS/ESC system. This paper describes a Unified Chassis Control (UCC) strategy for enhancing vehicle stability and ride comfort by the coordination of four In-Wheel Drive (IWD), 4-Wheel Independent Steering (4WIS), and Active Suspension Systems (ASS). Desired chassis motion is determined by generalized forces/moment calculated through a high-level sliding mode controller. Based on tire force constraints subject to allocated normal forces, the generalized forces/moment are distributed to the slip and slip angle of each tire by a fixed-point control allocation algorithm. Regarding the uneven road, H∞ robust controllers are proposed based on a modified quarter-car model. Evaluation of the overall system was accomplished by simulation testing with a full-vehicle CarSim model under different scenarios. The conclusion shows that the vertical vibration of the four wheels plays a detrimental role in vehicle stability, and the proposed method can effectively realize the tire force distribution to control the vehicle body attitude and driving stability even in high-demanding scenarios.

5.
Sensors (Basel) ; 21(10)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067746

RESUMO

The collision warning system (CWS) plays an essential role in vehicle active safety. However, traditional distance-measuring solutions, e.g., millimeter-wave radars, ultrasonic radars, and lidars, fail to reflect vehicles' relative attitude and motion trends. In this paper, we proposed a vehicle-to-vehicle (V2V) cooperative collision warning system (CCWS) consisting of an ultra-wideband (UWB) relative positioning/directing module and a dead reckoning (DR) module with wheel-speed sensors. Each vehicle has four UWB modules on the body corners and two wheel-speed sensors on the rear wheels in the presented configuration. An over-constrained localization method is proposed to calculate the relative position and orientation with the UWB data more accurately. Vehicle velocities and yaw rates are measured by wheel-speed sensors. An extended Kalman filter (EKF) is applied based on the relative kinematic model to combine the UWB and DR data. Finally, the time to collision (TTC) is estimated based on the predicted vehicle collision position. Furthermore, through UWB signals, vehicles can simultaneously communicate with each other and share information, e.g., velocity, yaw rate, which brings the potential for enhanced real-time performance. Simulation and experimental results show that the proposed method significantly improves the positioning, directing, and velocity estimating accuracy, and the proposed system can efficiently provide collision warning.

6.
J Cell Biochem ; 120(1): 470-480, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30161272

RESUMO

Gastric cancer (GC) is one of the most common malignancies and a leading cause of cancer-related death worldwide. Accumulating evidence reported that microRNA (miR)-133a was involved in GC. This study aimed to investigate the function and mechanism of miR-133a in the development and progression of GC. The expression of miR-133a and presenilin 1 (PSEN1) in two GC cell lines, SGC-7901 and BGC-823, were inhibited and overexpressed by transient transfections. Thereafter, cell viability, migration, and apoptosis were measured by trypan blue exclusion assay, transwell migration assay, and flow cytometry assay, respectively. Dual-luciferase reporter assay was conducted to verify whether PSEN1 was a direct target of miR-133a. Furthermore, quantitative real-time polymerase chain reaction and Western blot analysis were mainly performed to assess the expression changes of epithelial-mesenchymal transition (EMT)-associated proteins, apoptosis-related proteins, and Notch pathway proteins. MiR-133a inhibitor significantly increased cell viability and migration, while miR-133a mimic decreased cell viability, migration, and induced apoptosis. miR-133a suppression accelerated transforming growth factor-ß1 (TGF-ß1)-induce EMT, as evidenced by upregulation of E-cadherin, and downregulation of N-cadherin, vimentin, and Slug. Of contrast, miR-133a overexpression blocked TGF-ß1-induce EMT by altering these factors. PSEN1 was a direct target of miR-133a, and suppression of PSEN1 abolished the promoting functions of miR-133 suppression on cell growth and metastasis. Moreover, PSEN1 inhibition decreased Notch 1, Notch 2, and Notch 3 protein expressions. This study demonstrates an antigrowth and antimetastasis role of miR-133a in GC cells. Additionally, miR-133a acts as a tumor suppressor may be via targeting PSEN1.


Assuntos
Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , MicroRNAs/genética , Presenilina-1/genética , Neoplasias Gástricas/genética , Antígenos CD/metabolismo , Apoptose/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Mimetismo Molecular , Presenilina-1/metabolismo , RNA Interferente Pequeno/genética , Receptores Notch/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Transfecção , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima , Vimentina/metabolismo
7.
Plant Cell Rep ; 37(11): 1585-1595, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30099612

RESUMO

KEY MESSAGE: OsHSP50.2, an HSP90 family gene up-regulated by heat and osmotic stress treatments, positively regulates drought stress tolerance probably by modulating ROS homeostasis and osmotic adjustment in rice. Heat-shock proteins (HSPs) serve as molecular chaperones for a variety of client proteins in abiotic stress response and play pivotal roles in protecting plants against stress, but the molecular mechanism remains largely unknown. Here, we report an HSP90 family gene, OsHSP50.2, which acts as a positive regulator in drought stress tolerance in rice (Oryza sativa). OsHSP50.2 was ubiquitously expressed and its transcript level was up-regulated by heat and osmotic stress treatments. Overexpression of OsHSP50.2 in rice reduced water loss and enhanced the transgenic plant tolerance to drought and osmotic stresses. The OsHSP50.2-overexpressing plants exhibited significantly lower levels of electrolyte leakage and malondialdehyde (MDA) and less decrease of chlorophyll than wild-type plants under drought stress. Moreover, the OsHSP50.2-overexpressing plants had significantly higher SOD activity under drought stress compared with the wild type. These results imply that OsHSP50.2 positively regulates drought stress tolerance in rice, probably through the modulation of reactive oxygen species (ROS) homeostasis. Additionally, the OsHSP50.2-overexpressing plants accumulated significantly higher content of proline than the wild type under drought stress, which contributes to the improved protection ability from drought stress damage via osmotic adjustment. Our findings reveal that OsHSP50.2 plays a crucial role in drought stress response, and it may possess high potential usefulness in drought tolerance improvement of rice.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/metabolismo , Oryza/fisiologia , Secas , Expressão Gênica , Proteínas de Choque Térmico/genética , Homeostase , Temperatura Alta , Oryza/genética , Osmose , Pressão Osmótica , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Prolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico
8.
Genomics ; 102(1): 57-62, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23598252

RESUMO

Eulaliopsis binata is one of the best fiber grass plants for its high fiber quality and production. Large scale trancriptome sequencing of E. binata was first performed using mixed leaf samples of 20 wild clusters. A total of 26,438,832 clean reads were generated and were assembled into 59,134 isogenes with an average length of 845bp. BLAST against the NCBI non-redundant protein, KEGG and GO databases has classified these isogenes into functional categories for understanding gene functions and regulation pathways. Only 15.0% of the assembled isogenes were similar to known proteins and 24.4% has no hits in the nr protein database. The total isogenes and 5306 highly expressed isogenes were performed by BLASTx with the MAIZEWALL, the cell wall navigator and the PlantTFDB databases. A total of 6681 simple sequence repeats (SSRs) and 147,177 single nucleotide polymorphisms (SNPs) were detected in the isogenes and 5723 pairs of SSR primers were designed.


Assuntos
Perfilação da Expressão Gênica , Repetições de Microssatélites/genética , Anotação de Sequência Molecular , Poaceae/genética , Bases de Dados de Proteínas , Proteínas de Plantas , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
9.
Oncol Lett ; 27(2): 70, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38192676

RESUMO

Gastric cancer (GC) is the fifth most common cause of cancer-associated deaths; however, its treatment options are limited. Despite clinical improvements, chemotherapy resistance and metastasis are major challenges in improving the prognosis and quality of life of patients with GC. Therefore, effective prognostic biomarkers and targets associated with immunological interventions need to be identified. Solute carrier family 2 member 2 (SLC2A2) may serve a role in tumor development and invasion. The present study aimed to evaluate SLC2A2 as a prospective prognostic marker and chemotherapeutic target for GC. SLC2A2 expression in several types of cancer and GC was analyzed using online databases, and the effects of SLC2A2 expression on survival prognosis in GC were investigated. Clinicopathological parameters were examined to explore the association between SLC2A2 expression and overall survival (OS). Associations between SLC2A2 expression and immune infiltration, immune checkpoints and IC50 were estimated using quantification of the tumor immune contexture from human RNA-seq data, the Tumor Immune Estimation Resource 2.0 database and the Genomics of Drug Sensitivity in Cancer database. Differential SLC2A2 expression and the predictive value were validated using the Human Protein Atlas, Gene Expression Omnibus, immunohistochemistry and reverse transcription-quantitative PCR. SLC2A2 expression was downregulated in most types of tumor but upregulated in GC. Functional enrichment analysis revealed an association between SLC2A2 expression and lipid metabolism and the tumor immune microenvironment. According to Gene Ontology term functional enrichment analysis, SLC2A2-related differentially expressed genes were enriched predominantly in 'chylomicron assembly', 'plasma lipoprotein particle assembly', 'high-density lipoprotein particle', 'chylomicron', 'triglyceride-rich plasma lipoprotein particle', 'very-low-density lipoprotein particle'. 'intermembrane lipid transfer activity', 'lipoprotein particle receptor binding', 'cholesterol transporter activity' and 'intermembrane cholesterol transfer activity'. In addition, 'cholesterol metabolism', and 'fat digestion and absorption' were significantly enriched in the Kyoto Encyclopedia of Genes and Genomes pathway analysis. Patients with GC with high SLC2A2 expression had higher levels of neutrophil and M2 macrophage infiltration and a significant inverse correlation was observed between SLC2A2 expression and MYC targets, tumor mutation burden, microsatellite instability and immune checkpoints. Furthermore, patients with high SLC2A2 expression had worse prognosis, including OS, disease-specific survival and progression-free interval. Multivariate regression analysis demonstrated that SLC2A2 could independently prognosticate GC and the nomogram model showed favorable performance for survival prediction. SLC2A2 may be a prospective prognostic marker for GC. The prediction model may improve the prognosis of patients with GC in clinical practice, and SLC2A2 may serve as a novel therapeutic target to provide immunotherapy plans for GC.

10.
Mol Biol Rep ; 40(3): 2679-88, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23238922

RESUMO

There is increasing evidence for considerable interlinking between the responses to heat stress (HS) and light signaling. In the present work, we provide molecular evidence that BBX18, a negative regulator in photomorphogenesis belonging to the B-box zinc finger protein family in Arabidopsis thaliana, is involved in the regulation of thermotolerance. Using quantitative RT-PCR, GUS staining and immunoblot analysis, our results indicate that the expression of BBX18 was induced by HS. BBX18-RNAi and 35S::BBX18 transgenic Arabidopsis plants were obtained for functional analysis of BBX18. Under-expression of BBX18 displayed increased both basal and acquired thermotolerance in the transgenic plants, while over-expression of BBX18 reduced tolerance to HS in transgenic lines. Moreover, when wild-type, BBX18-RNAi and 35S::BBX18 transgenic plants were treated with HS, HR-related digalactosyldiacylglycerol synthase 1 (DGD1) was down-regulated by BBX18 in both normal and heat shock conditions. Besides, the expression levels of Hsp70, Hsp101 and APX2 were increased in BBX18-RNAi transgenic plants, but lower in 35S::BBX18 transgenic plants. However, the expression of HsfA2 was lower in BBX18-RNAi transgenic plants and higher in the 35S::BBX18 after high-temperature treatment. These results suggesting that, by modulated expression of a set of HS-responsive genes, BBX18 weakened tolerance to HS in Arabidopsis. So our data indicate that BBX18 plays a negative role in thermotolerance.


Assuntos
Adaptação Fisiológica/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Temperatura Alta , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Estudos de Associação Genética , Genótipo , Fenótipo , Dedos de Zinco
11.
Plant Cell Rep ; 32(11): 1795-806, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23949687

RESUMO

KEY MESSAGE: Expression of OsHsfB2b was strongly induced by heat, salt, ABA and PEG treatments. Drought and salt tolerances were significantly decreased by OsHsfB2b overexpression, but were enhanced by RNA interference. ABSTRACT: Plants have more than 20 heat shock factors (Hsfs) that were designated class A, B, and C. Many members of Class A Hsfs were characterized as activators of transcription, but the functional roles of class B and C Hsfs have not been fully recognized. OsHsfB2b is a member of class B Hsfs in rice (Oryza sativa). Expression of OsHsfB2b was strongly induced by heat, salt, abscisic acid (ABA) and polyethylene glycol (PEG) treatments but was almost not affected by cold stress. Drought and salt tolerances were significantly decreased in OsHsfB2b-overexpressing transgenic rice, but were enhanced in the OsHsfB2b-RNAi transgenic rice. Under drought stress, the OsHsfB2b-overexpressing transgenic rice exhibited increased relative electrical conductivity (REC) and content of malondialdehyde (MDA) and decreased proline content compared with the wild type, while the lower REC and MDA content and increased proline content were found in the OsHsfB2b-RNAi transgenic rice. These results suggest that OsHsfB2b functions as a negative regulator in response to drought and salt stresses in rice, with its existing B3 repression domain (BRD) that might be necessary for the repressive activity. The present study revealed the potential value of OsHsfB2b in genetic improvement of rice.


Assuntos
Secas , Proteínas de Choque Térmico/metabolismo , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Tolerância ao Sal/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Oryza/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Estresse Fisiológico/genética
12.
ScientificWorldJournal ; 2013: 397401, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24459431

RESUMO

During the long evolutionary process, plant gradually formed a series of strategies and mechanisms to cope with stress environment such as drought, heat, cold, and high salinity. Six highly heat responsive genes were identified in rice by microarray data analysis. The qRT-PCR analysis confirmed that the expression of these six genes were highly heat inducible and moderately responded to salt stress, polyethylene glycol, and abscisic acid treatment, but little affected by cold treatment. Promoters of the three highly heat-inducible genes (OsHsfB2cp, PM19p, and Hsp90p) were used to drive GUS gene expression in rice. The results of the GUS gene expression, histochemical staining, and GUS activities in panicles and flag leaves of the transgenic rice plants confirmed high heat-induced GUS activities and moderate drought-induced activities. The three promoters exhibited similar high activity lever in rice leaf under heat, but OsHsfB2cp and PM19p showed much higher activities in panicles under heat stress. Our work confirmed that the OsHsfB2c and PM19 promoters were highly heat inducible and further characterization and reconstruction of cis-elements in their promoters could lead to the development of highly effective heat-inducible promoters for plant genetic engineering.


Assuntos
Adaptação Biológica/genética , Evolução Biológica , Regulação da Expressão Gênica de Plantas/genética , Resposta ao Choque Térmico/genética , Oryza/genética , Ácido Abscísico , Biologia Computacional , Primers do DNA/genética , Perfilação da Expressão Gênica , Análise em Microsséries , Polietilenoglicóis , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real , Salinidade
13.
Mol Biol Rep ; 39(5): 6289-96, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22294104

RESUMO

Bast fibre crops are the second most important natural fibre crops following cotton. Of these, flax (Linum ustitatissimum L.) is the most widely planted in the world, with its fibre used for high quality linen textile. A cDNA library of flax bark tissues was constructed with the purpose of identifying genes involved in the Bast fibre development. A total of 2,297 unigene sequences were obtained from 3,200 randomly selected clones of the cDNA library. These sequences were grouped into 155 clusters and 2,142 singletons, which have been submitted to the GenBank databases. By putative functional annotation, 23.3% of these sequences were similar to known proteins in GenBank, 44.0% of these sequences were similar to unknown proteins, and 32.7% of these sequences showed no significant similarity to any other protein sequences in existing databases. Classified by the Gene Ontology, 24.8, 23.1 and 14.3% were assigned to molecular function, biological process, and cellular component GO terms, respectively. By further bioinformatics approaches, about 110 ESTs matched cell wall related genes in the MAIZEWALL database, representing 16 functional categories of all 19 categories, of which, the most abundant category was protein synthesis. Based on the PlantTFDB database, 39 of the 64 transcription factor families in the Arabidopsis thaliana genome were identified as being involved in flax cell wall formation. The sequences and bioinformatics analysis data generated in this paper will be useful for gene expression, cloning and genetic engineering studies to characterize bast fibre development and improve the properties of the bast fibres.


Assuntos
Etiquetas de Sequências Expressas , Linho/genética , Biblioteca Gênica , Casca de Planta/genética , Parede Celular/genética , Genes de Plantas/genética , Anotação de Sequência Molecular , Dados de Sequência Molecular , Análise de Sequência de DNA , Fatores de Transcrição/metabolismo
14.
Sci Prog ; 105(1): 368504211064476, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341410

RESUMO

The modeling and simulation research of fuel cell buses' power system is an important part of accelerating the process of industrialization. This paper firstly analyzes the advantages and disadvantages of different topologies of power systems to determine the optimal configuration, then conducts the parameter matching study of the power system, derives and determines the main vehicle dynamics parameters and the total power demand of the power system, and further completes the parameter matching of the drive motor, gear ratio and power supply, as well as the design of the fuel cell stack. On the Matlab/Simulink platform, the forward-backward energy flow balance method is used to establish a fuel cell power system model divided into power calculation modules and power shunt modules. Finally, model simulation and comparative analysis was car-ried out. The simulation results of the power system model in this paper were compared with the data of the 2010 World Expo FCB real-vehicle test. The result shows that the simulation results of the dynamic system is in good agreement with the real vehicle data. The power system model conforms to the actual situation, has feasibility and high engineering value.

15.
Plant Cell Rep ; 30(12): 2155-65, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21769604

RESUMO

Rice is the most important food crop worldwide. Global warming inevitably affects the grain yields of rice. Recent proteomics studies in rice have provided evidence for better understanding the mechanisms of thermal adaptation. Heat stress response in rice is complicated, involving up- or down-regulation of numerous proteins related to different metabolic pathways. The heat-responsive proteins mainly include protection proteins, proteins involved in protein biosynthesis, protein degradation, energy and carbohydrate metabolism, and redox homeostasis. In addition, increased thermotolerance in transgenic rice was obtained by overexpression of rice genes and genes from other plants. On the other hand, heterologous expression of some rice proteins led to enhanced thermotolerance in bacteria and other easily transformed plants. In this paper, we review the proteomic characterization of rice in response to high temperature and achievements of genetic engineering for heat tolerance in rice.


Assuntos
Engenharia Genética , Resposta ao Choque Térmico/genética , Temperatura Alta , Oryza/fisiologia , Proteoma/análise , Metabolismo dos Carboidratos , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/análise , Metaboloma , Oryza/genética , Oxirredução , Proteínas de Plantas/análise , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Transcriptoma
16.
Sci Prog ; 104(4): 368504211050284, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34723673

RESUMO

The plug-in hybrid electric vehicle not only has the advantages of low emissions from electric vehicles, but also takes advantage of the high specific energy and high specific power of petroleum fuels, which can significantly improve the emissions and fuel economy of traditional vehicles. Studying its comprehensive energy consumption evaluation method is an important part of analyzing the economics of plug-in hybrid electric vehicles. This paper first puts forward the concept of statistical energy consumption and then proposes an innovative calculation method of plug-in hybrid electric vehicle energy consumption based on statistical energy consumption by referring to and analyzing the energy consumption test regulations of the United States, the European Union, and China. Given the two use case assumptions of charge depleting mode priority and charge sustaining mode only, considering the fuel consumption and the energy consumption that converts electrical energy consumption to fuel consumption, the probability density function of travel mileage distribution and energy consumption is derived. Finally, the interpretation and analysis of statistical energy consumption evaluation results are carried out.

17.
J Phys Chem Lett ; 12(12): 3217-3223, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33761265

RESUMO

The recent discovery of negative Poisson's ratio (NPR) in two-dimensional (2D) atomic crystals has stimulated extensive research interest in their intriguing physical properties. Here, via density functional theory (DFT) calculations, we reveal in the family of 2D IV-VI semiconductors that an iso-symmetry structure variation concerning the switch of the cation (IV) versus anion (VI) in the outermost layers leads to the change of sign of Poisson's ratio. Such iso-symmetry structural pseudo-phase transition can be induced by external strains, as well as electric fields, realizing the possibility of an electrically switchable Poisson effect. The phase transition process could involve a dynamic intermediate state with an alternative cation/anion switch in the frequencies of 2-3 THz according to the real-time time-dependent DFT (rt-TDDFT) calculations. The results open the way for studying pseudophases in 2D materials associated with sharply different physical properties, such as Poisson's ratio, for electromechanical and optoelectronic applications.

18.
J Plant Res ; 123(1): 119-23, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19882206

RESUMO

Thirty-five microsatellite loci were isolated and characterized in Linum usitatissimum using enriched genomic libraries. These loci were screened in eight cultivars from different countries and regions and were found to be polymorphic, with the number of alleles per locus ranging from two to six, and observed and expected heterozygosities ranging from 0.125 to 0.375 (mean 0.013) and from 0.233 to 0.842 (mean 0.601), respectively. These polymorphic new microsatellite loci will be useful for genetic linkage map construction, germplasm classification and identification, gene identification and quantitative trait loci mapping, and marker-assisted selection in breeding in L. usitatissimum.


Assuntos
Linho/genética , Repetições de Microssatélites/genética , Polimorfismo Genético/genética , Alelos , Sequência de Bases , Repetições de Dinucleotídeos/genética , Frequência do Gene/genética , Genoma de Planta/genética , Dados de Sequência Molecular
19.
Int J Genomics ; 2020: 7582612, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33015150

RESUMO

To explore heat response mechanisms of mircoRNAs (miRNAs) in rice post-meiosis panicle, microarray analysis was performed on RNA isolated from rice post-meiosis panicles which were treated at 40°C for 0 min, 10 min, 20 min, 60 min, and 2 h. By integrating paired differentially expressed (DE) miRNAs and mRNA expression profiles, we found that the expression levels of 29 DE-miRNA families were negatively correlated to their 178 DE-target genes. Further analysis showed that the majority of miRNAs in 29 DE-miRNA families resisted the heat stress by downregulating their target genes and a time lag existed between expression of miRNAs and their target genes. Then, GO-Slim classification and functional identification of these 178 target genes showed that (1) miRNAs were mainly involved in a series of basic biological processes even under heat conditions; (2) some miRNAs might play important roles in the heat resistance (such as osa-miR164, osa-miR166, osa-miR169, osa-miR319, osa-miR390, osa-miR395, and osa-miR399); (3) osa-miR172 might play important roles in protecting the rice panicle under the heat stress, but osa-miR437, osa-miR418, osa-miR164, miR156, and miR529 might negatively affect rice fertility and panicle flower; and (4) osa-miR414 might inhibit the flowering gene expression by downregulation of LOC_Os 05g51830 to delay the heading of rice. Finally, a heat-induced miRNA-PPI (protein-protein interaction) network was constructed, and three miRNA coregulatory modules were discovered.

20.
Soft Robot ; 6(2): 276-288, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30650016

RESUMO

The improvement of the load capacity of soft grippers has always been a challenge. To tackle this load capacity challenge, this work presents four novel types of high-load (HL) soft grippers that are bioinspired by bionic winding models. The winding models are found commonly in many animals and plants, where different winding patterns are used to grip different objects. Inspired by the winding models, we design four bionic winding structures that are driven by pneumatic artificial muscles (PAMs), and then four HL soft grippers are formed out of the winding structures. The inner cavities of the HL soft grippers contract after the PAMs are inflated, which enables objects to be wrapped to achieve gripping. Compared with most existing soft grippers, the HL soft grippers have a higher load capacity, and they can also grip various objects that have different shapes and stiffnesses without damaging them. In addition, in man-machine collaboration, operators can be in direct contact with them without being hurt. Our study helps lay the foundation for engineered systems with bionic winding structures.


Assuntos
Biônica/instrumentação , Força da Mão/fisiologia , Robótica/instrumentação , Animais , Desenho de Equipamento/instrumentação
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