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1.
Struct Dyn ; 11(5): 054301, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39386199

RESUMO

The application of dynamic strain holds the potential to manipulate topological invariants in topological quantum materials. This study investigates dynamic structural deformation and strain modulation in the Weyl semimetal WTe2, focusing on the microscopic regions with static strain defects. The interplay of static strain fields, at local line defects, with dynamic strain induced from photo-excited coherent acoustic phonons results in the formation of local standing waves at the defect sites. The dynamic structural distortion is precisely determined utilizing ultrafast electron microscopy with nanometer spatial and gigahertz temporal resolutions. Numerical simulations are employed to interpret the experimental results and explain the mechanism for how the local strain fields are transiently modulated through light-matter interaction. This research provides the experimental foundation for investigating predicted phenomena such as the mixed axial-torsional anomaly, acoustogalvanic effect, and axial magnetoelectric effects in Weyl semimetals, and paves the road to manipulate quantum invariants through transient strain fields in quantum materials.

2.
J Hazard Mater ; 480: 135826, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39270588

RESUMO

Cadmium (Cd), a highly toxic heavy metal, profoundly impacts crop productivity. The bHLH-type transcription factors regulate plant stress responses, yet their involvement in maize's Cd stress response remains unclear. Here, we studied ZmbHLH105, a maize bHLH gene induced by Cd exposure. Overexpression of ZmbHLH105 in maize seedlings, which were treated with 1.0 mM CdCl2 for 7 days, increased endogenous ABA levels, decreased Cd accumulation, and enhanced Cd stress tolerance. ZmbHLH105 directly bound to promoter regions of two key ABA biosynthesis genes ZmNCED1/2, activating their transcription, thus boosting ABA levels and Cd tolerance. ZmbHLH105-overexpression promoted lignin synthesis, while ZmbHLH105-RNAi attenuated this effect. Exogenous ABA supplementation increased lignin content in Cd-stressed maize roots, suggesting ZmbHLH105-mediated Cd tolerance involves ABA-induced lignin deposition and cell wall thickening. Moreover, Cd transport-related gene expression was suppressed in ZmbHLH105 overexpression lines. Our findings demonstrate that ZmbHLH105 decreases Cd accumulation, improving Cd tolerance by enhancing ABA biosynthesis, increasing lignin deposition, thickening cell walls, and inhibiting Cd absorption in maize roots. This study unveils ZmbHLH105's mechanisms in Cd tolerance, highlighting its potential in breeding low Cd-accumulating crops for food and environment safety.

3.
Polymers (Basel) ; 16(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39204532

RESUMO

It is a formidable challenge in thermoplastic/lignin composites to simultaneously boost tensile strength and elongation performance due to the rigidity of lignin. To address this issue, sodium-alginate-doped lignin nanoparticles (SLNPs) were prepared by combining solvent exchange and a coprecipitation method and used as an eco-friendly filler for poly(butylene adipate-co-terephthalate) (PBAT). The results indicated that the 1% polyanionic sodium alginate solution contributed to the formation of SLNP in lignin/THF solution. SLNP with a mean hydrodynamic diameter of ~500 nm and a Zeta potential value of -19.2 mV was obtained, indicating more hydrophobic lignin nanoparticles and a smaller number of agglomerates in SLNP suspension. Only 0.5 wt% SLNP addition improved the yield strength, tensile strength, and elongation at break by 32.4%, 31.8%, and 35.1% of the PBAT/SLNP composite films, respectively. The reinforcing effect resulted from the rigid aromatic structure of SLNP, whereas the enhanced elongation was attributed to the nanostructural feature of SLNP, which may promote boundary cracking. Additionally, the PBAT/SLNP composite films displayed excellent ultraviolet (UV) resistance with a UV shielding percentage near 100% for UVB and more than 75% for UVA, respectively. The addition of SLNP hindered water vapor, enhancing the moisture barrier properties. Overall, this study provides an effective strategy to eliminate the decrement in elongation performance for PBAT/lignin composites and suggest they are good candidates to be extensively utilized.

4.
Int J Biol Macromol ; 271(Pt 1): 132499, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777014

RESUMO

In light of the depletion of petrochemical resources and increase in environmental pollution, there has been a significant focus on utilizing natural biomass, specifically lignin, to develop sustainable and functional materials. This research presents the development of a lignin-based polyurethane (DLPU) with photothermal-responsiveness by incorporating lignin and oxime-carbamate bonds into polyurethane network. The abundant hydrogen bonds between lignin and the polyurethane matrix, along with its cross-linked structure, contribute to DLPU's excellent mechanical strength (30.2 MPa) and toughness (118.7 MJ·m-3). Moreover, the excellent photothermal conversion ability of DLPU (54.4 %) activates dynamic reversible behavior of oxime-carbamate bonds and hydrogen bonds, thereby endowing DLPU with exceptional self-healing performance. After 15 min of near-infrared irradiation, DLPU achieves self-healing efficiencies of 96.0 % for tensile strength and 96.3 % for elongation at break. Additionally, DLPU exhibits photocontrolled solid-state plasticity as well as an excellent phototriggered shape-memory effect (70 s), with shape fixity and recovery ratios reaching 98.8 % and 95.3 %, respectively. By exploiting the spatial controllability and photothermal-responsiveness of DLPU, we demonstrate multi-dimensional responsive materials with self-healing and shape-shifting properties. This work not only promotes the development of multi-functional polyurethanes but also provides a pathway for the high-value utilization of lignin.


Assuntos
Lignina , Poliuretanos , Poliuretanos/química , Lignina/química , Resistência à Tração , Temperatura , Ligação de Hidrogênio , Fenômenos Mecânicos
5.
Animals (Basel) ; 14(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38672325

RESUMO

Sexual dimorphism of calls is common in animals, whereas studies on the molecular basis underlying this phenotypic variation are still scarce. In this study, we used comparative transcriptomics of cochlea to investigate the sex-related difference in gene expression and alternative splicing in four Rhinolophus taxa. Based on 31 cochlear transcriptomes, we performed differential gene expression (DGE) and alternative splicing (AS) analyses between the sexes in each taxon. Consistent with the degree of difference in the echolocation pulse frequency between the sexes across the four taxa, we identified the largest number of differentially expressed genes (DEGs) and alternatively spliced genes (ASGs) in R. sinicus. However, we also detected multiple DEGs and ASGs in taxa without sexual differences in echolocation pulse frequency, suggesting that these genes might be related to other parameters of echolocation pulse rather than the frequency component. Some DEGs and ASGs are related to hearing loss or deafness genes in human or mice and they can be considered to be candidates associated with the sexual differences of echolocation pulse in bats. We also detected more than the expected overlap of DEGs and ASGs in two taxa. Overall, our current study supports the important roles of both DGE and AS in generating or maintaining sexual differences in animals.

6.
Sci Rep ; 14(1): 8983, 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637684

RESUMO

Histone deacetylases (HDACs) contribute significantly to the initiation, progression, and prognosis of colorectal adenocarcinoma (COAD). Additionally, HDACs regulate the tumor microenvironment, immune escape, and tumor stem cells, and are closely linked to COAD prognosis. We developed a prognostic model for COAD that incorporates HDACs to evaluate their specific roles. The COAD dataset containing clinical and mutation data was collected using the TCGA and GEO databases to obtain genes associated with HDAC. LASSO analysis and univariate and multivariate Cox regression analysis were used to determine the presence of prognostic genes. Multivariate Cox analysis was also used to determine risk scores for HDAC-related features. Furthermore, genomic alterations, immune infiltration, and drug response were compared between high- and low-risk groups. Cellular experiments validated the potential regulatory role of BRD3 on COAD proliferation, migration, and apoptosis. The median risk scores, calculated based on the characteristics, demonstrated a more significant prognostic improvement in patients in the low-risk group. Furthermore, HDAC-related features were identified as important independent prognostic factors for patients with COAD. Additionally, genomic mutation status, immune infiltration, and function, as well as response to immunotherapy and chemotherapy, were found to be associated with risk scores. Subgroup analyses indicate that anti-PD-1 therapy may be beneficial for patients in the low-risk group. Additionally, a decrease in risk score was associated with a decrease in immune infiltration. Finally, HCT116 and HT29 cells exhibited inhibition of BRD3 gene proliferation and migration, as well as promotion of apoptosis. In patients with COAD, HDAC-related characteristics may be useful in predicting survival and selecting treatment.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Neoplasias Colorretais , Humanos , Prognóstico , Neoplasias do Colo/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Genes Reguladores , Histona Desacetilases/genética , Microambiente Tumoral/genética
7.
ACS Appl Bio Mater ; 7(3): 1801-1809, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38416780

RESUMO

Bacterial nanocellulose (BNC) is an attractive green-synthesized biomaterial for biomedical applications and various other applications. However, effective engineering of BNC production has been limited by our poor knowledge of the related metabolic processes. In contrast to the traditional perception that genome critically determines biosynthesis behaviors, here we discover that the glucose metabolism could also drastically affect the BNC synthesis in Gluconacetobacter hansenii. The transcriptomic profiles of two model BNC-producing strains, G. hansenii ATCC 53582 and ATCC 23769, which have highly similar genomes but drastically different BNC yields, were compared. The results show that their BNC synthesis capacities were highly related to metabolic activities such as ATP synthesis, ion transport protein assembly, and carbohydrate metabolic processes, confirming an important role of metabolism-related transcriptomes in governing the BNC yield. Our findings provide insights into the microbial biosynthesis behaviors from a transcriptome perspective, potentially guiding cellular engineering for biomaterial synthesis.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Transcriptoma/genética , Materiais Biocompatíveis , Engenharia Celular , Transporte de Íons
8.
ACS Appl Mater Interfaces ; 16(3): 4295-4305, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38217873

RESUMO

The interfacial solar-driven evaporation has been deemed as an environmentally friendly approach for freshwater generation. Nevertheless, there is still a challenge to obtain solar evaporators with efficient vapor production from low-cost and renewable biomass through a simple preparation process. Herein, the JUJUNCAO stem was selected as the substrate material, and a kind of interfacial solar-driven evaporator with natural two-phase composite structures and inherent ultralow water vaporization enthalpy was constructed by a dip-coating process. The natural two-phase composite structures were utilized as independent functional partition: the low-tortuosity and hydrophilic vascular bundles served as hierarchical channels for rapid water transportation and continuous steam escape, and the honeycomb-like parenchyma cells were considered natural heat insulators for effective thermal management. Furthermore, the JUJUNCAO stem exhibited inherent ultralow water vaporization enthalpy which was only 1.15 kJ g-1. Benefiting from the natural two-phase composite structures of functional partition and inherent ultralow water vaporization enthalpy, the C-Js evaporator could achieve an evaporation rate of 2.77 kg m-2 h-1 with an efficiency of 85.6% under 1 sun illumination. Meanwhile, the C-Js exhibited a stable and ideal evaporation performance and metal ion rejection behavior in the actual brine desalination process. Owing to the cost-effective and simple pretreatment process, the C-Js evaporator has the potential for freshwater generation in undeveloped areas.

9.
J Integr Plant Biol ; 65(12): 2645-2659, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37929676

RESUMO

Maize (Zea mays) requires substantial amounts of nitrogen, posing a challenge for its cultivation. Recent work discovered that some ancient Mexican maize landraces harbored diazotrophic bacteria in mucilage secreted by their aerial roots. To see if this trait is retained in modern maize, we conducted a field study of aerial root mucilage (ARM) in 258 inbred lines. We observed that ARM secretion is common in modern maize, but the amount significantly varies, and only a few lines have retained the nitrogen-fixing traits found in ancient landraces. The mucilage of the high-ARM inbred line HN5-724 had high nitrogen-fixing enzyme activity and abundant diazotrophic bacteria. Our genome-wide association study identified 17 candidate genes associated with ARM across three environments. Knockouts of one candidate gene, the subtilase family gene ZmSBT3, confirmed that it negatively regulates ARM secretion. Notably, the ZmSBT3 knockout lines had increased biomass and total nitrogen accumulation under nitrogen-free culture conditions. High ARM was associated with three ZmSBT3 haplotypes that were gradually lost during maize domestication, being retained in only a few modern inbred lines such as HN5-724. In summary, our results identify ZmSBT3 as a potential tool for enhancing ARM, and thus nitrogen fixation, in maize.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Zea mays/genética , Zea mays/microbiologia , Nitrogênio , Polissacarídeos , Bactérias
11.
Artigo em Inglês | MEDLINE | ID: mdl-37818577

RESUMO

INTRODUCTION: Magnolol is beneficial against inflammation-mediated damage. However, the underlying mechanisms by which m+agnolol exerts anti-inflammatory effects on macrophages remain unclear. OBJECTIVE: In this study, network pharmacology and experimental validation were used to assess the effect of magnolol on inflammation caused by lipopolysaccharide (LPS) in RAW264.7 cells. MATERIALS AND METHODS: Genes related to magnolol were identified in the PubChem and Swiss Target Prediction databases, and gene information about macrophage polarization was retrieved from the GeneCards, OMIM, and PharmGKB databases. Analysis of protein-protein interactions was performed with STRING, and Cytoscape was used to construct a component-target-disease network. GO and KEGG enrichment analyses were performed to ascertain significant molecular biological processes and signaling pathways. LPS was used to construct the inflammatory cell model. ELISA and qRT‒PCR were used to examine the expression levels of inflammationassociated factors, immunofluorescence was used to examine macrophage markers (CD86 and CD206), and western blotting was used to examine protein expression levels. RESULTS: The hub target genes of magnolol that act on macrophage polarization were MDM2, MMP9, IL-6, TNF, EGFR, AKT1, and ERBB2. The experimental validation results showed that magnolol treatment decreased the levels of proinflammatory factors (TNF-α, IL-1ß, and IL-6). Moreover, the levels of anti-inflammatory factors (IL-10 and IL-4) were increased. In addition, magnolol upregulated the expression of M2 markers (Agr-1, Fizzl, and CD206) and downregulated M1 markers (CD86). The cell experiment results supported the network pharmacological results and demonstrated that magnolol alleviated inflammation by modulating the PI3k-Akt and P62/keap1/Nrf2 signaling pathways. CONCLUSION: According to network pharmacology and experimental validation, magnolol attenuated inflammation in LPS-induced RAW264.7 cells mainly by inhibiting M1 polarization and enhancing M2 polarization by activating the PI3K/Akt and P62/keap1/Nrf2 signaling pathways.

12.
BMC Complement Med Ther ; 23(1): 239, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37461034

RESUMO

INTRODUCTION: Colon cancer remains one of the most prevalent cancers worldwide. Unfortunately, there are no recognized and effective therapeutic strategies to prevent tumor recurrence after radical resection and chemotherapy, and the disease-free survival (DFS) in patients with stage IIIB or IIIC disease remains unsatisfactory. Xian-Lian-Jie-Du optimization decoction (XLJDOD) is a Chinese herbal medicine (CHM) empirical prescription, which has been validated experimentally and clinically that could inhibit the progression of colorectal cancer and ameliorate the symptoms. The purpose of this study is to evaluate the efficacy and safety of XLJDOD in prevention of recurrence of colon cancer. METHODS: This study is a multi-center, double-blind, randomized, placebo-controlled trial conducted at 13 hospitals of China. Following the completion of surgery and adjuvant 5- fluorouracil-based chemotherapy, a total of 730 subjects with stage IIIB or IIIC colon cancer will be randomized in a 1:1 ratio to an intervention group (n = 365; XLJDOD compound granule) and a control group (n = 365; Placebo). Patients will receive 6-month treatments and be followed up with 3 monthly assessments for 2 years. The primary outcome is 2-year DFS rate and the secondary outcomes are 1, 2-year relapse rate (RR), overall survival (OS) and quality of life (QoL). Safety outcomes such as adverse events will be also assessed. A small number of subgroup analysis will be carried out to explore the heterogeneity of effects of XLJDOD. DISCUSSION: The outcomes from this randomized controlled trial will provide objective evidences to evaluate XLJDOD's role as an adjuvant treatment in colon cancer. TRIAL REGISTRATION: www. CLINICALTRIALS: gov , identifier: NCT05709249. Registered on 31 Jan 2023.


Assuntos
Neoplasias do Colo , Qualidade de Vida , Humanos , Resultado do Tratamento , Neoplasias do Colo/tratamento farmacológico , Intervalo Livre de Doença , Método Duplo-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
13.
Microbiol Resour Announc ; 12(8): e0034923, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37395667

RESUMO

A complete genome is presented for Microbacterium proteolyticum ustc, a member of the Gram-positive order Micrococcales of the phylum Actinomycetota that is resistant to high concentrations of heavy metals and participates in metal detoxification. The genome consists of one plasmid and one chromosome.

14.
Plant Biotechnol J ; 21(9): 1812-1826, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37293701

RESUMO

Fusarium verticillioides (F. verticillioides) is a widely distributed phytopathogen that incites multiple destructive diseases in maize, posing a grave threat to corn yields and quality worldwide. However, there are few reports of resistance genes to F. verticillioides. Here, we reveal that a combination of two single nucleotide polymorphisms (SNPs) corresponding to ZmWAX2 gene associates with quantitative resistance variations to F. verticillioides in maize through a genome-wide association study. A lack of ZmWAX2 compromises maize resistance to F. verticillioides-caused seed rot, seedling blight and stalk rot by reducing cuticular wax deposition, while the transgenic plants overexpressing ZmWAX2 show significantly increased immunity to F. verticillioides. A natural occurrence of two 7-bp deletions within the promoter increases ZmWAX2 transcription, thus enhancing maize resistance to F. verticillioides. Upon Fusarium stalk rot, ZmWAX2 greatly promotes the yield and grain quality of maize. Our studies demonstrate that ZmWAX2 confers multiple disease resistances caused by F. verticillioides and can serve as an important gene target for the development of F. verticillioides-resistant maize varieties.


Assuntos
Fusarium , Zea mays/genética , Estudo de Associação Genômica Ampla , Resistência à Doença/genética , Variação Genética/genética , Doenças das Plantas/genética
15.
Toxicology ; 491: 153513, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37075930

RESUMO

Microplastics (MPs) with a diameter of < 5 mm are emerging as a new type of environmental pollutants. With the discovery of MPs in human tissues, the health risks of MPs have attracted considerable attention in recent years. In this study, we aimed to investigate the impact of MPs on acute pancreatitis (AP). We exposed male mice to 100 and 1000 µg/L polystyrene MPs for 28 days, then intraperitoneally injected mice with cerulein to develop acute pancreatitis (AP). The results demonstrated that MPs dose-dependently exacerbated pancreatic injuries and inflammation in AP. High-dose MPs significantly increased intestinal barrier disruption in AP mice, which may be partly responsible for the aggravation of AP. Moreover, through tandem mass tag (TMT)- based proteomics of pancreatic tissues, we screened 101 differentially expressed proteins (DEPs) between AP mice and high-dose MPs-treated AP mice. Gene Ontology and KEGG Pathway analysis revealed that the DEPs were mainly implicated in the molecular events including cytoskeleton organization, acute inflammatory response, arginine metabolism, etc. These mechanisms may also contribute to the aggravating AP effects of MPs. Collectively, our data provide new evidence for the harmful potential of MPs.


Assuntos
Pancreatite , Camundongos , Masculino , Humanos , Animais , Pancreatite/induzido quimicamente , Pancreatite/metabolismo , Poliestirenos/toxicidade , Microplásticos/toxicidade , Plásticos , Doença Aguda , Inflamação
16.
Ecotoxicol Environ Saf ; 254: 114746, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36905845

RESUMO

Heat stress (HS) has become a serious threat to crop growth and yield. Sulfur dioxide (SO2) is being verified as a signal molecule in regulating the plant stress response. However, it is unknown whether SO2 plays a significant role in the plant heat stress response (HSR). Herein, maize seedlings were pretreated with various concentrations of SO2 and then kept at 45 °C for heat stress treatment, aiming to study the effect of SO2 pretreatment on HSR in maize by phenotypic, physiological, and biochemical analyses. It was found that SO2 pretreatment greatly improved the thermotolerance of maize seedlings. The SO2-pretreated seedlings showed 30-40% lower ROS accumulation and membrane peroxidation, but 55-110% higher activities of antioxidant enzymes than the distilled water-pretreated seedlings under heat stress. Interestingly, endogenous salicylic acid (SA) levels were increased by ∼85% in SO2-pretreated seedlings, as revealed by phytohormone analyses. Furthermore, the SA biosynthesis inhibitor paclobutrazol markedly reduced SA levels and attenuated SO2-triggered thermotolerance of maize seedlings. Meanwhile, transcripts of several SA biosynthesis and signaling, and heat stress-responsive genes in SO2-pretreated seedlings were significantly elevated under HS. These data have demonstrated that SO2 pretreatment increased endogenous SA levels, which activated the antioxidant machinery and strengthened the stress defense system, thereby improving the thermotolerance of maize seedlings under HS. Our current study provides a new strategy for mitigating heat stress damage for safe crop production.


Assuntos
Antioxidantes , Termotolerância , Antioxidantes/farmacologia , Plântula , Zea mays , Dióxido de Enxofre/farmacologia , Ácido Salicílico/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-36884009

RESUMO

Currently, there have been widespread investigation conducted into responsive photonic crystal hydrogels (RPCHs) characterized by high selectivity and sensitivity for colorimetric indicators and physical/chemical sensors. In spite of this, it remains challenging to use RPCHs for sensing due to their limited mechanical property and molding capability. In the present study, a double-network structure is proposed to design highly stretchable, sensitive, and reusable ion-detection photonic papers (IDPPs) for assessing the quality of visual and portable comestible liquids (e.g., soy sauce). It is constructed by integrating polyacrylamide and poly-methacryloxyethyl trimethyl ammonium chloride with highly ordered polystyrene microspheres. The double-network structure improves the mechanical properties of IDPPs with their elongation at break increasing from 110 to 1600%. Meanwhile, the optical properties of photonic crystals are retained. The IDPPs achieve a fast ion response by applying control on the swelling behavior of the hydration radius of the counter ions through ion exchange. Given a certain concentration range (0.01-0.10 M), chloride ions can be detected fast (3-30 s) by exchanging ions with a small hydration radius through an IDPP, which is clearly observable. Due to the improvement of mechanical properties and the reversible exchange of ions derived from IDPPs, their reusability is significantly enhanced (>30 times). Characterized by a simple operation, high durability, and excellent sustainability, these IDPPs are promising for practical application in food security and human health assessment.

18.
Adv Sci (Weinh) ; 9(29): e2203305, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35986431

RESUMO

Microwaves have become a promising wireless driving strategy due to the advantages of transmissivity through obstacles, fast energy targeting, and selective heating. Although there are some studies on microwave powered artificial muscles based on different structures, the lack of studies on microwave control has limited the development of microwave-driven (MWD) robots. Here, a far-field MWD parallel robot controlled by adjusting energy distribution via changing the polarization direction of microwaves at 2.47 GHz is first reported. The parallel robot is based on three double-layer bending actuators composed of wave-absorbing sheets and bimetallic sheets, and it can implement circular and triangular path at a distance of 0.4 m under 700 W transmitting power. The thermal response rate of the actuator under microwaves is studied, and it is found that the electric-field components can provide a faster thermal response at the optimal length of actuator than magnetic-field components. The work of the parallel robot is demonstrated in an enclosed space composed of microwave-transparent materials. This developed method demonstrates the multi-degree-of-freedom controllability for robots using microwaves and offers potential solutions for some engineering cases, such as pipeline/reactors inspection and medical applications.


Assuntos
Micro-Ondas , Robótica , Calefação/métodos , Campos Magnéticos , Músculos
19.
Artigo em Inglês | MEDLINE | ID: mdl-35830501

RESUMO

Developing a shape memory polyurethane with high mechanical properties, excellent self-healing has become a huge challenge for the development of smart materials. Herein, we report the design and fabrication of a shape memory polyurethane network terminated with coumarin units (HEOMC-PU) to address this conundrum. The synthesized HEOMC-PU exhibits exceptional mechanical performance with a breaking elongation of 746% and toughness of 55.5 MJ·m-3. By utilizing the dynamically reversible behavior of coumarin units to repair the damaged network, the efficient self-healing performance (99.2%) of HEOMC-PU is obtained. In addition, the prepared network and light-induced dynamic reversibility endow the HEOMC-PU with both liquid-state remoldability and solid-state plasticity, respectively, enabling polyurethane to be recycled and processed multiple times. Furthermore, based on the fluorescence responsive characteristic of coumarin, HEOMC-PU with a fluorescent pattern can be deformed into specific three-dimensional configurations by combining photolithography, self-healing, and the shape memory effect. Such a multilevel and multidimensional anti-counterfeiting platform with rewritable fluorescent patterns and reconfigurable shapes can open up a new encryption approach for future intelligent anti-counterfeiting.

20.
Mol Plant Pathol ; 23(10): 1446-1460, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35700097

RESUMO

Although microRNAs (miRNAs) regulate the defence response against multiple pathogenic fungi in diverse plant species, few efforts have been devoted to deciphering the involvement of miRNA in resistance to Fusarium verticillioides, a major pathogenic fungus affecting maize production. In this study, we discovered a novel F. verticillioides-responsive miRNA designated zma-unmiR4 in maize kernels. The expression of zma-unmiR4 was significantly repressed in the resistant maize line but induced in the susceptible lines upon exposure to F. verticillioides exposure, whereas its target gene ZmGA2ox4 exhibited the opposite pattern of expression. Heterologous overexpression of zma-unmiR4 in Arabidopsis resulted in enhanced growth and compromised resistance to F. verticillioides. By contrast, transgenic plants overexpressing ZmGA2ox4 or the homologue AtGA2ox7 showed impaired growth and enhanced resistance to F. verticillioides. Moreover, zma-unmiR4-mediated suppression of AtGA2ox7 disturbed the accumulation of bioactive gibberellin (GA) in transgenic plants and perturbed the expression of a set of defence-related genes in response to F. verticillioides. Exogenous application of GA or a GA biosynthesis inhibitor modulated F. verticillioides resistance in different plants. Taken together, our results suggest that the zma-unmiR4-ZmGA2ox4 module might act as a major player in balancing growth and resistance to F. verticillioides in maize.


Assuntos
Fumonisinas , Fusarium , MicroRNAs , Fumonisinas/metabolismo , Fusarium/metabolismo , MicroRNAs/genética , Plantas Geneticamente Modificadas/metabolismo , Zea mays/microbiologia
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