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1.
Soft Matter ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623704

RESUMO

Hydrogel-based flexible electronic devices serve as a next-generation bridge for human-machine interaction and find extensive applications in clinical therapy, military equipment, and wearable devices. However, the mechanical mismatch between hydrogels and human tissues, coupled with the failure of conformal interfaces, hinders the transmission of information between living organisms and flexible devices, which resulted in the instability and low fidelity of signals, especially in the acquisition of electromyographic (EMG) and electrocardiographic (ECG) signals. In this study, we designed an ion-conductive hydrogel (ICHgel) utilizing multiple physical interactions, successfully applied for human motion monitoring and the collection of epidermal physiological signals. By incorporating fumed silica (F-SiO2) nanoparticles and calcium chloride into an interpenetrating network (IPN) composed of polyvinyl alcohol (PVA) and polyacrylamide (AAm)/acrylic acid (AA) chains, the ICHgel exhibited exceptional tunable stretchability (>1450% strain) and conductivity (10.58 ± 0.85 S m-1). Additionally, the outstanding adhesion of the ICHgel proved to be a critical factor for effective communication between epidermal tissues and flexible devices. Demonstrating its capability to acquire stable electromechanical signals, the ICHgel was attached to different parts of the human body. More importantly, as a flexible electrode, the ICHgel outperformed commercial Ag/AgCl electrodes in the collection of ECG and EMG signals. In summary, the synthesized ICHgel with its outstanding conformal interface capabilities and mechanical adaptability paves the way for enhanced human-machine interaction, fostering the development of flexible electronic devices.

2.
ACS Sens ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502945

RESUMO

The flexible bimodal e-skin exhibits significant promise for integration into the next iteration of human-computer interactions, owing to the integration of tactile and proximity perception. However, those challenges, such as low tactile sensitivity, complex fabrication processes, and incompatibility with bimodal interactions, have restricted the widespread adoption of bimodal e-skin. Herein, a bimodal capacitive e-skin capable of simultaneous tactile and proximity sensing has been developed. The entire process eliminates intricate fabrication techniques, employing DLP-3D printing for the electrode layers and sacrificial templating for the dielectric layers, conferring high tactile sensitivity (1.672 kPa-1) and rapid response capability (∼30 ms) to the bimodal e-skin. Moreover, exploiting the "fringing electric field" effect inherent in parallel-plate capacitors has facilitated touchless sensing, thereby enabling static distance recognition and dynamic gesture recognition of varying materials. Interestingly, an e-skin sensing array was created to identify the positions and pressure levels of various objects of different masses. Furthermore, with the aid of machine learning techniques, an artificial neural network has been established to possess intelligent object recognition capabilities, facilitating the identification, classification, and training of various object configurations. The advantages of the bimodal e-skin render it highly promising for extensive applications in the field of next-generation human-machine interaction.

3.
Med Sci Monit ; 30: e942945, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38442083

RESUMO

BACKGROUND The aim of this study was to assess clinical outcomes of arthroscopic surgery for gluteal muscle contracture (GMC) with at least 2 years of follow-up in a large sample. MATERIAL AND METHODS A total of 665 patients who underwent arthroscopic release procedure at our institution between March 2014 and December 2018 and met the inclusion criteria were included in this study. All the patients were operated on by the same surgeon and the surgeon released the contracture band from anterior to posterior starting from the anterior edge of the ITB, the contracture band of the gluteus maximus, and vastus medialis tensor. After exclusion, 544 patients (218 males and 326 females) were finally included. Clinical outcomes at 2 years of postoperative follow-up were evaluated by a combination of several methods, including a new criterion we proposed for postoperative assessment, which included the cross-leg test, difficulty in squatting with legs together, and abnormal gait, the visual analogue scale (VAS), the modified Harris hip score (mHHS), and the satisfaction of patients. RESULTS The average follow-up time was 48.2±14.9 months. Based on the new criteria, 513 (94.3%) patients were evaluated as good, 25 (4.6%) as fair, and 6 (1.1%) as poor. The mHHS increased from 72.1±6.0 (range, 56.0-81.3) to 97.3±2.2 (range, 92.3-100.0) (P<0.001). The VAS decreased from 3.3±1.1 (range, 0-5) to 0.062±0.13 (range, 0-1) (P<0.001). For subjective satisfaction, 526 (96.7%) patients were satisfied, 14 (2.6%) patients were neutral, and 4 (0.7%) patients were dissatisfied. CONCLUSIONS In a large sample, favorable and durable clinical outcomes were observed after the arthroscopic procedure. Clinical symptoms and mHHS showed significant improvement with a minimum 2-year follow-up.


Assuntos
Artroscopia , Contratura , Feminino , Masculino , Humanos , Extremidade Inferior , Contratura/cirurgia , Perna (Membro) , Músculo Quadríceps
5.
Respir Res ; 25(1): 16, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178098

RESUMO

BACKGROUND: Growing evidence from observational studies and clinical trials suggests that the gut microbiota is associated with tuberculosis (TB). However, it is unclear whether any causal relationship exists between them and whether causality is bidirectional. METHODS: A bidirectional two-sample Mendelian randomization (MR) analysis was performed. The genome-wide association study (GWAS) summary statistics of gut microbiota were obtained from the MiBioGen consortium, while the GWAS summary statistics of TB and its specific phenotypes [respiratory tuberculosis (RTB) and extrapulmonary tuberculosis (EPTB)] were retrieved from the UK Biobank and the FinnGen consortium. And 195 bacterial taxa from phylum to genus were analyzed. Inverse variance weighted (IVW), MR-Egger regression, maximum likelihood (ML), weighted median, and weighted mode methods were applied to the MR analysis. The robustness of causal estimation was tested using the heterogeneity test, horizontal pleiotropy test, and leave-one-out method. RESULTS: In the UK Biobank database, we found that 11 bacterial taxa had potential causal effects on TB. Three bacterial taxa genus.Akkermansia, family.Verrucomicrobiacea, order.Verrucomicrobiales were validated in the FinnGen database. Based on the results in the FinnGen database, the present study found significant differences in the characteristics of gut microbial distribution between RTB and EPTB. Four bacterial taxa genus.LachnospiraceaeUCG010, genus.Parabacteroides, genus.RuminococcaceaeUCG011, and order.Bacillales were common traits in relation to both RTB and TB, among which order.Bacillales showed a protective effect. Additionally, family.Bacteroidacea and genus.Bacteroides were identified as common traits in relation to both EPTB and TB, positively associating with a higher risk of EPTB. In reverse MR analysis, no causal association was identified. No significant heterogeneity of instrumental variables (IVs) or horizontal pleiotropy was found. CONCLUSION: Our study supports a one-way causal relationship between gut microbiota and TB, with gut microbiota having a causal effect on TB. The identification of characteristic gut microbiota provides scientific insights for the potential application of the gut microbiota as a preventive, diagnostic, and therapeutic tool for TB.


Assuntos
Microbioma Gastrointestinal , Tuberculose Pulmonar , Tuberculose , Humanos , Microbioma Gastrointestinal/genética , Análise da Randomização Mendeliana , Estudo de Associação Genômica Ampla , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/genética
6.
Sensors (Basel) ; 23(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37960609

RESUMO

Dynamic characteristics play a crucial role in evaluating the performance of weight sensors and are essential for achieving fast and accurate weight measurements. This study focuses on a weight sensor based on optical coherence displacement. Using finite element analysis, the sensor was numerically simulated. Frequency domain and time domain dynamic response characteristics were explored through harmonic response analysis and transient dynamic analysis. The superior dynamic performance and reduced conditioning time of the non-contact optical coherence-based displacement weight sensor were confirmed via a negative step response experiment that compared the proposed sensing method to strain sensing. Moreover, dynamic performance metrics for the optical coherence displacement-type weight sensor were determined. Ultimately, the sensor's dynamic performance was enhanced using the pole-zero placement method, decreasing the overshoot to 4.72% and reducing the response time to 0.0132 s. These enhancements broaden the sensor's operational bandwidth and amplify its dynamic response capabilities.

7.
Mater Horiz ; 10(9): 3610-3621, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37334834

RESUMO

Conductive elastomers with both softness and conductivity are widely used in the field of flexible electronics. Nonetheless, conductive elastomers typically exhibit prominent problems such as solvent volatilization and leakage, and poor mechanical and conductive properties, which limit their applications in electronic skin (e-skin). In this work, a liquid-free conductive ionogel (LFCIg) with excellent performance was fabricated by utilizing the innovative double network design approach based on a deep eutectic solvent (DES). The double-network LFCIg is cross-linked by dynamic non-covalent bonds, which exhibit excellent mechanical properties (2100% strain while sustaining a fracture strength of 1.23 MPa) and >90% self-healing efficiency, and a superb electrical conductivity of 23.3 mS m-1 and 3D printability. Moreover, the conductive elastomer based on LFCIg has been developed into a stretchable strain sensor that achieves accurate response recognition, classification, and identification of different robot gestures. More impressively, an e-skin with tactile sensing functions is produced by in situ 3D printing of sensor arrays on flexible electrodes to detect light weight objects and recognize the resulting spatial pressure variations. Collectively, the results demonstrate that the designed LFCIg has unparalleled advantages and presents wide application potential in flexible robotics, e-skin and physiological signal monitoring.


Assuntos
Percepção do Tato , Dispositivos Eletrônicos Vestíveis , Elastômeros , Tato
8.
Mater Horiz ; 10(3): 1012-1019, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36655678

RESUMO

Natural biological tissues such as ligaments, due to their anisotropic across scale structure, have high water content, while still maintaining high strength and flexibility. Hydrogels are ideal artificial materials like human ligaments. However, conventional gel materials fail to exhibit high strength or fatigue resistance at high water content in human tissues. To address this challenge, we propose a simple integrated strategy to prepare an anisotropic hierarchical hydrogel architecture for artificial ligaments by combining freeze-casting assisted compression annealing and salting-out treatments. The hybrid polyvinyl alcohol hydrogels are of water content up to 79.5 wt%. Enhanced by the added carbon nanotubes, the hydrogels exhibit high strength of 4.5 MPa and a fatigue threshold of 1467 J m-2, as well as excellent stress sensitivity. The outstanding durability of the artificial ligament provides an all-around solution for biomedical applications.


Assuntos
Hidrogéis , Nanotubos de Carbono , Humanos , Água
9.
Membranes (Basel) ; 12(10)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36295760

RESUMO

Due to the complexity of both material composition and the structure of the catalyst layer (CL) used in the proton-exchange membrane fuel cell (PEMFC), conjugated heat and mass transfer as well as electrochemical processes simultaneously occur through the CL. In this study, a microstructure model of CL was first reconstructed using images acquired by Nano-computed tomography (Nano-CT) of a real sample of CL. Then, the multiphysics dynamic distribution (MPDD) simulation, which is inherently a multiscale approach made of a combination of pore-scale and homogeneous models, was conducted on the reconstructed microstructure model to compute the corresponded heat and mass transport, electrochemical reactions, and water phase-change processes. Considering a computational domain with the size of 4 um and cube shape, this model consisting of mass and heat transport as well as electrochemical reactions reached a stable solution within 3 s as the convergence time. In the presence of sufficient oxygen, proton conduction was identified as the dominant factor determining the strength of the electrochemical reaction. Additionally, it was concluded that current density, temperature, and the distribution of water all exhibit similar distribution trends, which decrease from the interface between CL and the proton-exchange membrane to the interface between CL and the gas-diffusion layer. The present study not only provides an in-depth understanding of the mass and heat transport and electrochemical reaction in the CL microstructure, but it also guides the optimal design and fabrication of CL components and structures, such as improving the local structure to reduce the number of dead pores and large agglomerates, etc.

10.
J Appl Microbiol ; 133(2): 808-818, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35429104

RESUMO

AIMS: NDT80, a known transcriptional factor, regulates various targets, including regulation of meiosis, stress responses, filamentous growth, sexual development, biofilm formation, drug resistance, and virulence. But the numbers and roles of Ndt80-like genes in different fungi are highly variable. This study aims to address the numbers and functions of Ndt80-like genes in Coniothyrium minitans, a well-known biocontrol agent against Sclerotinia diseases. METHODS AND RESULTS: Here, two genes (CmNdt80a and CmNdt80b) encoding NDT80-like proteins were obtained by searching the genomic sequence of C. minitans. RT-PCR analysis showed that both CmNdt80 genes were constitutively expressed in C. minitans from the hyphal growth stage (48 hpi) to the pycnidial maturation stage (120 hpi). The roles of CmNdt80a and CmNdt80b in C. minitans were verified through gene knockout and complementation experiments. The results showed that the ΔCmNdt80a mutants exhibited a lighter colour and normal growth rate on potato dextrose agar plates. The ability of the ΔCmNdt80a mutants to produce conidia and parasitize the colony and sclerotia of Sclerotinia sclerotiorum was markedly diminished compared with the wild-type strain and complemented strain. Interestingly, the ΔCmNdt80a mutant showed less sensitivity to cell wall stressors and cell wall-degrading enzymes, and had thicker cell walls than the wild-type strain and complemented strain. However, no phenotypic consequences were discovered for the deletion of CmNdt80b. CONCLUSIONS: Two Ndt80-like genes, CmNdt80a and CmNdt80b, were present in C. minitans. CmNdt80a, but not CmNdt80b, plays a crucial role in conidiogenesis, mycoparasitism, and cell wall integrity. SIGNIFICANCE AND IMPACT OF THE STUDY: Understanding the mechanisms that regulate the conidiation and parasitism of C. minitans could help us to more efficiently utilize this biological control agent and advance our knowledge of fungal biology.


Assuntos
Ascomicetos , Fatores de Transcrição , Ascomicetos/metabolismo , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Esporos Fúngicos
11.
Mitochondrial DNA B Resour ; 6(11): 3263-3264, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712804

RESUMO

We report the complete mitochondrial genome (mtDNA) of Pareas formosensis (Squamata: Colubridae). This circular mtDNA is 17,703 bp in size and consists of 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, and 2 non-coding sequence (D-loop). The total of mtDNA was composition of 57.26% A + T and 42.74% G + C (T: 25.21%, C: 28.84%, A: 32.05%, G: 13.90%). The phylogenetic analysis revealed that P. formosensis formed a clade with other species of Pareas. This mtDNA sequence of P. formosensis provides useful data for studying the population genetics and phylogeography of Colubridae.

12.
Pediatr Investig ; 5(3): 203-210, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34540320

RESUMO

Importance: The Coronavirus disease 2019 (COVID-19) global pandemic poses a considerable challenge for pediatricians. Objective: This study aimed to identify the epidemiological characteristics and clinical features of pediatric patients with COVID-19 in China. Methods: This multicenter retrospective study included pediatric patients from 46 hospitals in China, covering 12 provinces and two municipalities. Epidemiological, demographic, clinical, laboratory, treatment, and outcome data were analyzed. Results: In total, 211 pediatric patients with COVID-19 were included in this study. The median age was 7.0 years (range: 22 days to 18 years). Approximately 16.3% of the patients exhibited asymptomatic infections, 23.0% had upper respiratory tract infections, and 60.7% had pneumonia, including two with severe pneumonia and one with critical illness. Approximately 78.7% of the pediatric patients occurred in familial clusters. The most three common symptoms or signs at onset in children with COVID-19 were fever (54.5%), cough (49.3%), and pharyngeal congestion (20.8%). Only 17.6% of the patients presented with decreased lymphocyte count, whereas 13.6% had increased lymphocyte count. Among the patients with pneumonia who exhibited abnormal chest computed tomography findings, 18.2% (23/127) of the patients had no other symptoms. Generally, the chest radiographs showed abnormalities that affected both lungs (49.6%); ground-glass opacity (47.2%) was the most common manifestation. The cure and improvement rates were 86.7% (183/211) and 13.3% (28/211), respectively. Only one patient with an underlying condition received invasive mechanical ventilation; none of the patients died. Interpretation: Similar to adults, children of all age groups are susceptible to COVID-19. Fortunately, most pediatric patients have mild symptoms or remain asymptomatic, despite the high incidence of pneumonia. Decreased proportions of white blood cells and lymphocytes are less frequent in children than in adults.

14.
ACS Appl Mater Interfaces ; 12(36): 40815-40827, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32794689

RESUMO

Hydrogels are important for stretchable and wearable multifunctional sensors, but their application is limited by their low mechanical strength and poor long-term stability. Herein, a conductive organohydrogel with a 3D honeycomb structure was prepared by integrating carbon nanotubes (CNTs) and carbon black (CB) into a poly(vinyl alcohol)/glycerol (PVA/Gly) organohydrogel. Such a nanocomposite organohydrogel is built on a physical cross-linking network formed by the hydrogen bonds among PVA, glycerol, and water. CNTs and CB had an add-in synergistic impact on the mechanical and electrical performances of the PVA/Gly organohydrogel because of the distinct aspect ratios and geometric shapes. The prepared organohydrogel integrated with a tensile strength of 4.8 MPa, a toughness of 15.93 MJ m-3, and flexibility with an elongation at break up to 640%. The organohydrogels also showed good antifreezing feature, long-term moisture retention, self-healing, and thermoplasticity. Sensors designed from these organohydrogels displayed high stretching sensitivity to tensile strain and temperature, with a gauge factor of 2.1 within a relatively broad strain range (up to ∼600% strain), a temperature coefficient of resistance of -0.935%·°C-1, and long-term durability. The sensors could detect full-range human physiological signals and respond to the change in temperature, which are highly desired for multifunctional wearable electronic devices.

15.
Sci Rep ; 10(1): 12576, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724140

RESUMO

Biological control mechanisms of plant diseases have been intensively studied. However, how plant pathogens respond to and resist or alleviate biocontrol agents remains largely unknown. In this study, a comparative transcriptome analysis was performed to elucidate how the pathogen of sclerotinia stem rot, Sclerotinia sclerotiorum, responds and resists to the biocontrol agent, Bacillus amyloliquefaciens. Results revealed that a total of 2,373 genes were differentially expressed in S. sclerotiorum samples treated with B. amyloliquefaciens fermentation broth (TS) when compared to control samples (CS). Among these genes, 2,017 were upregulated and 356 were downregulated. Further analyses indicated that various genes related to fungal cell wall and cell membrane synthesis, antioxidants, and the autophagy pathway were significantly upregulated, including glucan synthesis, ergosterol biosynthesis pathway, fatty acid synthase, heme-binding peroxidase related to oxidative stress, glutathione S-transferase, ABC transporter, and autophagy-related genes. These results suggest that S. sclerotiorum recruits numerous genes to respond to or resist the biocontrol of B. amyloliquefaciens. Thus, this study serves as a valuable resource regarding the mechanisms of fungal pathogen resistance to biocontrol agents.


Assuntos
Ascomicetos/genética , Bacillus amyloliquefaciens/química , Agentes de Controle Biológico/farmacologia , Proteínas Fúngicas/genética , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Bacillus amyloliquefaciens/metabolismo , Agentes de Controle Biológico/química , Agentes de Controle Biológico/metabolismo , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , /microbiologia
16.
Nanotechnology ; 31(33): 335504, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32353833

RESUMO

Flexible sensors at small scales have potential applications in many fields. Until now, the research on high-performance vibration sensors based on soft materials with high sensitivity and precision, fast response and high stability are still in its infancy. In this work, a flexible, wearable and high precision film sensor based on multi-walled carbon nanotube (MWCNT) was prepared via a vacuum filtration process and then encapsulated within polydimethylsiloxane (PDMS). The sensor exhibits an ultrahigh sensitivity with gauge factor of 214.3 at flexural strain of 0.4%. When used to monitor the vibration responses of a carbon-fiber beam induced by the base excitation and impact hammer, the time and frequency responses were comparable with the results obtained by the accelerometer, with difference less than 1\!%. In addition, when the MWCNT/PDMS thin film was employed as an electronic skin sensor attached on the human body to detect human activities, the high sensitivity and repeatability demonstrate a great potential application in monitoring human motion.

17.
Appl Environ Microbiol ; 86(5)2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31836578

RESUMO

Coniothyrium minitans is an important mycoparasite of the notorious phytopathogenic fungus Sclerotinia sclerotiorum The mycoparasitism system of C. minitans-S. sclerotiorum is unique and important in probing fungi and fungal interactions. Here, we report a conidiation-deficient mutant, ZS-1TN1961, which was screened from a transfer DNA (T-DNA) insertional library of C. minitans A single-copy gene, encoding a protein with high sequence similarity to Aim24 (altered inheritance of mitochondria protein 24) in Saccharomyces cerevisiae, was disrupted by T-DNA insertion in this mutant. Gene replacement and complementation experiments confirmed that mutants lacking CmAim24 exhibited significantly reduced conidial production and germination as well as reduced sclerotial mycoparasitic ability. Furthermore, cellular localization assays showed that CmAim24 localized to mitochondria, and abnormal mitochondria were observed in the ΔCmAim24 mutant. The ΔCmAim24 mutant exhibited significant accumulation of reactive oxygen species (ROS) and a reduced ATP content in mycelia. In summary, our results suggest that CmAim24 plays a key role in mitochondrial architecture and function, conidiogenesis, and mycoparasitism in C. minitansIMPORTANCE Aim24 proteins are involved in mitochondrial biogenesis and accumulate between the two membranes of a mitochondrion. Their function in prokaryotes and filamentous fungi is as yet unknown. In the present study, we characterized an Aim24 protein, CmAim24, in the mycoparasite Coniothyrium minitans and proved its critical role in mitochondrial morphology and function, conidiogenesis, conidial germination, and mycoparasitism to S. sclerotiorum.


Assuntos
Ascomicetos/fisiologia , Proteínas Fúngicas/genética , Interações entre Hospedeiro e Microrganismos , Esporos Fúngicos/crescimento & desenvolvimento , Proteínas Fúngicas/metabolismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo
18.
Sensors (Basel) ; 19(2)2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30646618

RESUMO

A flexible hybrid film consisting of graphene nanoplatelets (GNPs) and multi-walled carbon nanotubes (MWCNTs) was prepared and employed as a multifunctional sensor to monitor temperature and liquid leakage, based on the piezoresistive effect. The influences of the GNP content on the mechanical, thermal, and sensing properties were investigated. Experimental results showed that both the hardness and Young's modulus of the hybrid film were decreased with an increasing GNP content, while the thermal conductivity exhibited in an opposite trend. The electrical resistance of the hybrid film decreased was linearly with an increase in temperature. The resistance change increased linearly with an increase of the solvent adsorption. These features demonstrated the potential applications of the hybrid film in the detection of temperature, and liquid leakage. The sensitivity of leakage detection is increasing with the increase of the GNP loading, while temperature sensitivity is in the opposite trend.

19.
Front Microbiol ; 9: 2658, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30467498

RESUMO

Coniothyrium minitans is a sclerotial parasite, which has been investigated for commercial control of crop diseases caused by Sclerotinia sclerotiorum. Previously, we obtained a T-DNA insertional mutant, ZS-1TN24363, which did not produce melanin during conidiation. To understand the function of melanin in C. minitans, we cloned the gene that was disrupted by the T-DNA insertion, and found that this gene, called CmMR1, encoded a putative protein of 1,011 amino acids, which is a homolog of the transcription factor MR. Full-length CmMR1 contains 3,167 bp, with three exons and two introns. To confirm that the disrupted gene is responsible for the melanin-deficiency of the mutant, CmMR1 was disrupted and three targeted knockout mutants were obtained. Biological assays showed that the phenotype of the targeted knockout mutants was similar to that of the T-DNA insertional mutant. Furthermore, gene complementation confirmed that CmMR1 is responsible for the mutant phenotype. CmMR1 disruption did not affect hyphal growth, conidiation, and parasitization of C. minitans, however, the ROS accumulation increased and tolerance to UV light decreased significantly in the mutants. Our result may enhance the understanding of melanin in the ecology of C. minitans on molecular level.

20.
Nanomaterials (Basel) ; 8(10)2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30287756

RESUMO

Graphene nanoplatelet (GNP) and multi-walled carbon nanotube (MWCNT) hybrid films were prepared with the aid of surfactant Triton X-100 and sonication through a vacuum filtration process. The influence of GNP content ranging from 0 to 50 wt.% on the mechanical and electrical properties was investigated using the tensile test and Hall effect measurement, respectively. It showed that the tensile strength of the hybrid film is decreasing with the increase of the GNP content while the electrical conductivity exhibits an opposite trend. The effectiveness of the MWCNT/GNP hybrid film as a strain sensor is presented. The specimen is subjected to a flexural loading, and the electrical resistance measured by a two-point probe method is found to be function of applied strain. Experimental results demonstrate that there are two different linear strain-sensing stages (0⁻0.2% and 0.2⁻1%) in the resistance of the hybrid film with applied strain. The strain sensitivity is increasing with the increase of the GNP content. In addition, the repeatability and stability of the strain sensitivity of the hybrid film were conformed through the cyclic loading⁻unloading tests. The MWCNT/GNP hybrid film shows promising application for strain sensing.

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