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1.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(2): 338-344, 2024 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-38595255

RESUMO

OBJECTIVE: To observe the clinical effect of arthrocentesis combined with liquid phase concentrated growth factor (CGF) injection in the treatment of unilateral temporomandibular joint osteoarthritis (TMJOA), in order to provide a new treatment option for TMJOA patients. METHODS: In this non-randomized controlled study, patients diagnosed with unilateral TMJOA who visited the center for temporomandibular joint disorder and orofacial pain of Peking University School and Hospital of Stomatology from June 2021 to January 2023 were selected as research objects. The patients were divided into experimental group and control group, which were selected by patients themselves. The experimental group received arthrocentesis combined with liquid phase CGF injection and the control group received arthrocentesis combined with HA injection. Both groups were treated 3 times, once every two weeks. The clinical effect was evaluated by the maximum mouth opening, pain value and the degree of mandibular function limitation 6 months after treatment. The change of condylar bone was evaluated by cone beam CT (CBCT) image fusion technology before and after treatment. RESULTS: A total of 20 patients were included in the experimental group, including 3 males and 17 females, with an average age of (34.40±8.41) years. A total of 15 patients were included in the control group, including 1 male and 14 females, with an average age of (32.20±12.00) years. There was no statistical difference in general information between the two groups (P > 0.05). There were no statistical differences in the mouth opening, pain value and the degree of jaw function limitation between the two groups before treatment (P > 0.05), and all of them improved 6 months after treatment compared with before treatment (P < 0.05). However, the mouth opening of experimental group was significantly higher than that of control group 6 months after treatment (P < 0.05), and the degree of jaw function limitation was significantly lower than that of control group (P < 0.05). CBCT 2D images showed that the condylar bone of both groups was smoother after treatment than before treatment, and image fusion results showed that 10 patients (50.0%) in the experimental group and 5 patients (33.3%) in the control group had reparative remodeling area of condylar bone, and there was no statistical difference between them (P > 0.05). Except for one CGF patient, the other patients in both groups had some absorption areas of condylar bone. CONCLUSION: The arthrocentesis combined with liquid phase CGF injection can improve the clinical symptoms and signs of unilateral TMJOA patients in short term, and is better than HA in increasing mouth opening and improving jaw function. CBCT fusion images of both patient groups show some cases of condylar bone reparative remodeling and its relevance to treatment plans still requires further study.


Assuntos
Artrocentese , Osteoartrite , Feminino , Humanos , Masculino , Adulto , Adulto Jovem , Articulação Temporomandibular , Osteoartrite/tratamento farmacológico , Dor/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intercelular , Resultado do Tratamento , Injeções Intra-Articulares , Ácido Hialurônico/uso terapêutico
2.
mSphere ; 9(1): e0056423, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38170984

RESUMO

The emergence of antibiotic-resistant and biofilm-producing Staphylococcus aureus isolates presents major challenges for treating staphylococcal infections. Biofilm inhibition is an important anti-virulence strategy. In this study, a novel maleimide-diselenide hybrid compound (YH7) was synthesized and demonstrated remarkable antimicrobial activity against methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) in both planktonic cultures and biofilms. The minimum inhibitory concentration (MIC) of YH7 for S. aureus isolates was 16 µg/mL. Quantification of biofilms demonstrated that the sub-MIC (4 µg/mL) of YH7 significantly inhibits biofilm formation in both MSSA and MRSA. Confocal laser scanning microscopy analysis further confirmed the biofilm inhibitory potential of YH7. YH7 also significantly suppressed bacterial adherence to A549 cells. Moreover, YH7 treatment significantly inhibited S. aureus colonization in nasal tissue of mice. Preliminary mechanistic studies revealed that YH7 exerted potent biofilm-suppressing effects by inhibiting polysaccharide intercellular adhesin (PIA) synthesis, rather than suppressing bacterial autolysis. Real-time quantitative PCR data indicated that YH7 downregulated biofilm formation-related genes (clfA, fnbA, icaA, and icaD) and the global regulatory gene sarX, which promotes PIA synthesis. The sarX-dependent antibiofilm potential of YH7 was validated by constructing S. aureus NCTC8325 sarX knockout and complementation strains. Importantly, YH7 demonstrated a low potential to induce drug resistance in S. aureus and exhibited non-toxic to rabbit erythrocytes, A549, and BEAS-2B cells at antibacterial concentrations. In vivo toxicity assays conducted on Galleria mellonella further confirmed that YH7 is biocompatible. Overall, YH7 demonstrated potent antibiofilm activity supports its potential as an antimicrobial agent against S. aureus biofilm-related infections. IMPORTANCE Biofilm-associated infections, characterized by antibiotic resistance and persistence, present a formidable challenge in healthcare. Traditional antibacterial agents prove inadequate against biofilms. In this study, the novel compound YH7 demonstrates potent antibiofilm properties by impeding the adhesion and the polysaccharide intercellular adhesin production of Staphylococcus aureus. Notably, its exceptional efficacy against both methicillin-resistant and methicillin-susceptible strains highlights its broad applicability. This study highlights the potential of YH7 as a novel therapeutic agent to address the pressing issue of biofilm-driven infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Camundongos , Coelhos , Staphylococcus aureus , Staphylococcus aureus Resistente à Meticilina/genética , Meticilina/farmacologia , Antibacterianos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Biofilmes
3.
Clin Implant Dent Relat Res ; 26(1): 197-205, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37674300

RESUMO

OBJECTIVES: The main purpose of this retrospective study was to assess the difference in the incidence of peri-zygomatic complications (PZCs) when zygomatic implants (ZIs) penetrate or do not penetrate the external surface of zygoma. MATERIALS AND METHODS: This study included 32 patients with edentulous maxillae or potentially edentulous maxillae undergo zygomatic implantation. The patients were divided into the penetration group (P-group) and the non-penetration group (N-group) according to whether the apex of implants penetrated the external surface of zygoma in postoperative CBCT. The extension length, the penetration section of the implants, and the skin thickness at the corresponding position were simultaneously measured. Clinical follow-up was conducted regularly until 2 years after surgery. The occurrence of PZCs (including peri-zygomatic infection, skin numbness, non-infectious pain, and foreign body sensation) was recorded. A mixed effect logistic model was used to compare the difference of complication rate between the P-group and the N-group, and odds ratio (OR) was calculated. Then identify the impact of the extension length, penetration section and skin thickness in P-group with the same model. RESULTS: A total of 71 ZIs were implanted in 32 patients, including 37 implants in the P-group and 34 implants in the N-group. During the 2-year follow-up, a total of 13 implants occurred PZCs, with an overall complication rate of 18.3%. Thereinto, the incidence rate was 29.7% in the P-group, and 5.9% in the N-group (OR = 6.77). In P-group, there was a significant difference in complication rate of different extension lengths, while the penetration section and skin thickness had no statistical significance on the complication rate. CONCLUSION: Under the limitation of this study, to minimize the risk of PZCs, ZI should be placed in a manner that avoids the apex penetrating the external surface of the zygoma.


Assuntos
Implantes Dentários , Arcada Edêntula , Humanos , Implantação Dentária Endóssea , Implantes Dentários/efeitos adversos , Estudos Retrospectivos , Zigoma/cirurgia , Prótese Dentária Fixada por Implante , Maxila/cirurgia , Arcada Edêntula/cirurgia , Seguimentos
4.
Artigo em Inglês | MEDLINE | ID: mdl-38158268

RESUMO

OBJECTIVE: Herein, we aimed to study the clinical, radiographical, and histopathologic features of synovial chondromatosis in the temporomandibular joint (SC in TMJ) and provide references for early diagnosis and treatment prognosis. STUDY DESIGN: The medical records and imaging examinations of patients with SC in TMJ, diagnosed using postoperative histopathologic examination, were reviewed and analyzed. Among them, 18 cases who lacked calcified loose bodies on spiral computed tomography or cone beam computed tomography (SCT/CBCT) were selected for further study. Descriptive statistical methods were used to analyze the clinical characteristics of patients. RESULTS: The study included 100 patients with SC in TMJ, who were predominantly female (male to female: 1:3), and were aged from 21 to 77 years (median, 47). Radiopaque calcified lesions on SCT/CBCT were missing in 18 cases, but cartilaginous nodules were observed during surgery. The cases lacking calcification had a relatively shorter disease course, suggesting they were in the early stages of SC. CONCLUSION: In the early stage of SC, although calcified loose bodies cannot be detected on SCT/CBCT, attention should be paid to the widening of the posterior superior joint space and sclerosis or slight erosion of the joint fossa. Magnetic resonance imaging would be helpful to detect the early-stage SC in TMJ.


Assuntos
Condromatose Sinovial , Humanos , Feminino , Masculino , Condromatose Sinovial/diagnóstico por imagem , Condromatose Sinovial/cirurgia , Estudos Retrospectivos , Articulação Temporomandibular/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Progressão da Doença
5.
Microbiol Spectr ; 11(6): e0159623, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37819121

RESUMO

IMPORTANCE: Biofilms are an important virulence factor in Staphylococcus aureus and are characterized by a structured microbial community consisting of bacterial cells and a secreted extracellular polymeric matrix. Inhibition of biofilm formation is an effective measure to control S. aureus infection. Here, we have synthesized a small molecule compound S-342-3, which exhibits potent inhibition of biofilm formation in both MRSA and MSSA. Further investigations revealed that S-342-3 exerts inhibitory effects on biofilm formation by reducing the production of polysaccharide intercellular adhesin and preventing bacterial adhesion. Our study has confirmed that the inhibitory effect of S-342-3 on biofilm is achieved by downregulating the expression of genes responsible for biofilm formation. In addition, S-342-3 is non-toxic to Galleria mellonella larvae and A549 cells. Consequently, this study demonstrates the efficacy of a biologically safe compound S-342-3 in inhibiting biofilm formation in S. aureus, thereby providing a promising antibiofilm agent for further research.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Biofilmes , Aderência Bacteriana , Staphylococcus aureus Resistente à Meticilina/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Testes de Sensibilidade Microbiana
6.
Nanoscale ; 15(38): 15513-15551, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37740390

RESUMO

Although electrospinning (e-spinning) has witnessed rapid development in recent years, it has also been criticized by environmentalists due to the use of organic solvents. Therefore, aqueous e-spinning (green e-spinning) is considered a more attractive technique. However, considering the poor water resistance and mechanical properties of electrospun (e-spun) nanofibers, cross-linking is a perfect solution. In this review, we systematically discuss the cross-linking e-spinning system for the first time, including cross-linking strategies (in situ, liquid immersion, vapor, and spray cross-linking), cross-linking mechanism (physical and chemical cross-linking) of e-spun nanofibers, and the various applications (e.g., tissue engineering, drug delivery, water treatment, food packaging, and sensors) of cross-linked e-spun nanofibers. Among them, we highlight several cross-linking methods, including UV light cross-linking, electron beam cross-linking, glutaraldehyde (and other commonly used cross-linking agents) chemical cross-linking, thermal cross-linking, and enzymatic cross-linking. Finally, we confirm the significance of cross-linking e-spinning and reveal the problems in the construction of this system.

7.
Talanta ; 265: 124924, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37437393

RESUMO

Point-of-care testing methods currently utilize rapid, portable, inexpensive, and multiplexed on-site detection. Microfluidic chips have become a very promising platform with broad development prospects due to their breakthrough improvement in miniaturization and integration. However, the conventional microfluidic chips still have disadvantages, such as difficulty in fabrication processing, long production time and high cost, which hinder its applications in the fields of POCT and in vitro diagnostics. In this study, a capillary-based microfluidic chip with the characteristics of low cost and easy fabrication was developed for the rapid detection of acute myocardial infarction (AMI). Several short capillaries, which were already conjugated with the capture antibodies respectively, were connected by peristaltic pump tubes and then formed the working capillary. Two working capillaries were encapsulated in the plastic shell and ready for the immunoassay. Multiplex detection of Myoglobin (Myo), cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) were chosen to demonstrate the feasibility and analytical performance of the microfluidic chip, which requires rapid and accurate detection during diagnosis and therapy for AMI. The capillary-based microfluidic chip required tens of minutes to prepared, and its cost was less than $1. The limit of detection (LOD) was 0.5 ng/mL for Myo, 0.1 ng/mL for cTnI and 0.5 ng/mL for CK-MB respectively. The capillary-based microfluidic chips with easy fabrication and low cost hold promise for the portable and low-cost detection of target biomarkers.


Assuntos
Microfluídica , Infarto do Miocárdio , Humanos , Capilares , Infarto do Miocárdio/diagnóstico , Troponina I , Creatina Quinase Forma MB , Biomarcadores , Mioglobina
8.
Microbiol Spectr ; 11(3): e0004523, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37166296

RESUMO

Staphylococcus aureus is an important human pathogen and brings about many community-acquired, hospital-acquired, and biofilm-associated infections worldwide. It tends to form biofilms, triggering the release of toxins and initiating resistance mechanisms. As a result of the development of S. aureus tolerance to antibiotics, there are few drugs can availably control biofilm-associated infections. In this study, we synthesized a novel small-molecule compound CY-158-11 (C22H14Cl2NO2Se2) and proved its inhibitory effect on the biofilm formation of S. aureus at a subinhibitory concentration (1/8 MIC). The subinhibitory concentration of CY-158-11 not only did not affect the growth of bacteria but also had no toxicity to A549 cells or G. mellonella. Total biofilm biomass was investigated by crystal violet staining, and the results were confirmed by SYTO 9 and PI staining through confocal laser scanning microscopy. Moreover, CY-158-11 effectively prevented initial attachment and repressed the production of PIA instead of autolysis. RT-qPCR analysis also exhibited significant suppression of the genes involved in biofilm formation. Taken together, CY-158-11 exerted its inhibitory effects against the biofilm formation in S. aureus by inhibiting cell adhesion and the expression of icaA related to PIA production. IMPORTANCE Most bacteria exist in the form of biofilms, often strongly adherent to various surfaces, causing bacterial resistance and chronic infections. In general, antibacterial drugs are not effective against biofilms. The small-molecule compound CY-158-11 inhibited the biofilm formation of S. aureus at a subinhibitory concentration. By hindering adhesion and PIA-mediated biofilm formation, CY-158-11 exhibits antibiofilm activity toward S. aureus. These findings point to a novel therapeutic agent for combating intractable S. aureus-biofilm-related infections.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Antibacterianos/farmacologia , Biofilmes , Infecções Estafilocócicas/tratamento farmacológico , Violeta Genciana/farmacologia , Testes de Sensibilidade Microbiana
9.
Nanoscale ; 15(5): 2003-2017, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36645211

RESUMO

Thermal management plays a vital role in technology (electronic and electrical equipment) and life (high-temperature injury). Therefore, thermal regulation has attracted worldwide attention. This review addresses the applications of electrospinning (e-spinning) in the thermal management of polymer matrix composites, mainly involving enhanced thermal conductivity (TC), thermal insulation, and passive daytime radiative cooling (PDRC). In particular, in the regulation of TC, e-spinning can uniformly distribute active fillers in the composites to achieve bidirectional control. The types of active filler and its connection forms in the composites are discussed emphatically. In addition, PDRC without energy consumption is also highlighted. Finally, the current challenges and future development are addressed.

10.
Emerg Microbes Infect ; 12(1): 2165969, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36628606

RESUMO

Previous studies have shown that the increased prevalent ST764 clone in China, Japan, and other Asian areas. However, the knowledge of the genetic features and virulence characteristics of methicillin-resistant Staphylococcus aureus (MRSA) ST764 in China is still limited. In this study, we identified 52 ST764-SCCmec type II isolates collected from five cities in China between 2014 and 2021. Whole genome sequencing showed that the most common staphylococcal protein A (spa) types of ST764 in China were t002 (55.78%) and t1084 (40.38%). Virulence assays showed that ST764-t1084 isolates had high haemolytic activity and α-toxin levels. Of the critical regulatory factors affecting α-toxin production, only the SaeRS was highly expressed in ST764-t1084 isolates. Mouse abscess model indicated that the virulence of ST764-t1084 isolates was comparable to that of S. aureus USA300-LAC famous for its hypervirulence. Interestingly, ST764-t002 isolates exhibited stronger biofilm formation and cell adhesion capacities than ST764-t1084 isolates. This seems to explain why ST764-t002 subclone has become more prevalent in China in recent years. Phylogenetic analysis suggested that all ST764 isolates from China in Clade III were closely related to KUN1163 (an isolate from Japan). Notably, genomic analysis revealed that the 52 ST764 isolates did not carry arginine catabolic mobile element (ACME), which differed from ST764 isolates in Japan. Additionally, most ST764 isolates (69.23%) harboured an obvious deletion of approximately 5 kb in the SCCmec II cassette region compared to KUN1163. Our findings shed light on the potential global transmission and genotypic as well as phenotypic characteristics of ST764 lineage.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Camundongos , Staphylococcus aureus Resistente à Meticilina/genética , Antibacterianos , Filogenia , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus , Virulência , Genótipo , Fatores de Virulência/genética
11.
Front Plant Sci ; 13: 1085409, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570905

RESUMO

Plants are exposed to increasingly severe drought events and roots play vital roles in maintaining plant survival, growth, and reproduction. A large body of literature has investigated the adaptive responses of root traits in various plants to water stress and these studies have been reviewed in certain groups of plant species at a certain scale. Nevertheless, these responses have not been synthesized at multiple levels. This paper screened over 2000 literatures for studies of typical root traits including root growth angle, root depth, root length, root diameter, root dry weight, root-to-shoot ratio, root hair length and density and integrates their drought responses at genetic and morphological scales. The genes, quantitative trait loci (QTLs) and hormones that are involved in the regulation of drought response of the root traits were summarized. We then statistically analyzed the drought responses of root traits and discussed the underlying mechanisms. Moreover, we highlighted the drought response of 1-D and 2-D root length density (RLD) distribution in the soil profile. This paper will provide a framework for an integrated understanding of root adaptive responses to water deficit at multiple scales and such insights may provide a basis for selection and breeding of drought tolerant crop lines.

12.
Micromachines (Basel) ; 13(11)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36422395

RESUMO

A novel three-dimensional (3D) wafer-level sandwich packaging technology is here applied in the dual mass MEMS butterfly vibratory gyroscope (BFVG) to achieve ultra-high Q factor. A GIS (glass in silicon) composite substrate with glass as the main body and low-resistance silicon column as the vertical lead is processed by glass reflow technology, which effectively avoids air leakage caused by thermal stress mismatch. Sputter getter material is used on the glass cap to further improve the vacuum degree. The Silicon-On-Insulator (SOI) gyroscope structure is sandwiched between the composite substrate and glass cap to realize vertical electrical interconnection by high-vacuum anodic bonding. The Q factors of drive and sense modes in BFVG measured by the self-developed double closed-loop circuit system are significantly improved to 8.628 times and 2.779 times higher than those of the traditional ceramic shell package. The experimental results of the processed gyroscope also demonstrate a high resolution of 0.1°/s, the scale factor of 1.302 mV/(°/s), and nonlinearity of 558 ppm in the full-scale range of ±1800°/s. By calculating the Allen variance, we obtained the angular random walk (ARW) of 1.281°/√h and low bias instability (BI) of 9.789°/h. The process error makes the actual drive and sense frequency of the gyroscope deviate by 8.989% and 5.367% compared with the simulation.

13.
Microbiol Spectr ; 10(6): e0134622, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36374095

RESUMO

With the globally prevailing carbapenemase-producing (CP) Citrobacter spp., polymyxin antibiotics have been reconsidered as one of the last-resort treatment options. Our study was conducted to investigate the prevalence of mcr-9 in Citrobacter species. From October to November 2021, 650 fecal samples and 215 Citrobacter isolates were collected from healthy individuals and infected patients, respectively. Isolates were screened for the presence of the mcr-9 gene by the PCR method. mcr-9-carrying strains were identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Due to the susceptibility to colistin, Citrobacter spp. isolates were first induced to increase the expression of mcr-9 on China blue agar plates containing colistin and were then subjected to conjugation experiments. Whole-genome sequencing was performed on the Illumina NovaSeq PE150 system. The prevalence of mcr-9 in the Citrobacter genus from healthy guts and infected patients was 0.62% and 1.86%, respectively. In all mcr-9-positive strains, MICs of polymyxin B were observed at ≤2 µg/mL, displaying a nonresistant phenotype. As for conjugation experiments, only one isolate successfully transferred the mcr-9 gene to Escherichia coli C600. Whole-genome sequencing showed that eight mcr-9-positive Citrobacter isolates carried mcr-9 and genes encoding resistance to beta-lactam antibiotics, including blaCMY, blaDHA, blaSHV, blaTEM, and blaCTX-M. We also discovered that mcr-9 could be located on the pKPC-CAV1321 plasmid. Our study investigated the prevalence of mcr-9 in Citrobacter spp. in both healthy individuals and infected patients and described the carriage of mcr-9 on the pKPC-CAV1321 plasmid for the first time. IMPORTANCE The emergence of mcr homologues posed a serious threat to the therapeutic efficiency of polymyxin antibiotics. Citrobacter freundii is generally regarded as an opportunistic pathogen associated with a variety of nosocomial infections. In this study, we investigated the prevalence of mcr-9 in Citrobacter spp. isolates from healthy individuals and infected patients and highlighted the importance of the rational use of antibiotics. In addition, this epidemiological investigation is the first to describe the carriage of mcr-9 on plasmid pKPC-CAV1321 and confirms the horizontal transfer of this plasmid. Our research may shed new light on further studies of mcr-9 dissemination in humans.


Assuntos
Citrobacter , Colistina , Humanos , Antibacterianos/farmacologia , beta-Lactamases/genética , Citrobacter/genética , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli , Testes de Sensibilidade Microbiana , Plasmídeos/genética
14.
Nanoscale ; 14(30): 11018-11027, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35866357

RESUMO

Quantum transport in multi-channel silicon nanowire transistors presents enhanced data capacity and driving ability by overlapping current, which are essential for constructing quantum logic platforms. However, the overlapping behavior of the quantum transport through multi-channels remains elusive. Herein, we demonstrated bias-dependent hole transport spectroscopy from zero-dimensional (0D) to one-dimensional (1D) features in a lightly boron-doped multi-channel silicon nanowire transistor. The evolution of the initial 0D conductance peak splitting with source/drain bias voltages reveals the statistically distributed positions of single dopant atoms in multi-channels relative to the source or drain side. Two sets of 1D subbands are determined separately for heavy and light holes with different effective masses by measuring the positions of transconductance valleys, which have a negative shift with increasing bias voltage. Our results will benefit the practical utilization of silicon-based devices with atomic-level functionality in the field of quantum computation.

15.
Small ; 18(26): e2201989, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35620957

RESUMO

Rechargeable zinc-ion batteries (ZIBs) with exceptional theoretical capacity have garnered significant interest in large-scale electrochemical energy storage devices due to their low cost, abundant material, inherent safety, high specific energy, and ecofriendly nature. Metal carbides/nitrides, known as MXenes, have emerged as a large family of 2D transition metal carbides or carbonitrides with excellent properties, e.g., high electrical conductivity, large surface functional groups (e.g., F, O, and OH), low energy barriers for the diffusion of electrolyte ions with wide interlayer spaces. After a decade of effort, significant development has been achieved in the synthesis, properties, and applications of MXenes. Thus, it has opened up various exciting opportunities to construct advanced MXene-based nanostructures for ZIBs with excellent specific energy and power. Herein, this review summarizes the advances across multiple synthesis routes, related properties, morphological and structural characteristics, and chemistries of MXenes for ZIBs. The recent development of MXene-based electrodes is introduced, and electrolytes for ZIBs are elucidated in detail. MXene-based rocking chair ZIBs, strategies to enhance the performance of MXene-based cathodes, suppress the dendrites in MXene-based anodes, and MXene-based flexible ZIBs are pointed out. A rational design and modification of the MXenes as well as the production of composites with metal oxides exhibits promise in solving issues and enhancing the electrochemical performance of ZIBs. Finally, the present challenges and future prospects for MXene-based ZIBs are discussed.

16.
Mater Horiz ; 9(7): 1999-2006, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35608360

RESUMO

Metal oxide semiconductors are promising candidate photoelectrodes for photoelectrochemical H2O2 production if the issues of poor efficiency and selectivity can be resolved. An unfavorable charge transport barrier causes poor carrier collection and kinetics, limiting their efficiency and selectivity. Herein, BiFeO3 was used as the model photocathode, and its interfacial charge transport barrier between fluorine-doped tin oxide substrates was modulated by introducing a LaNiO3 layer as the charge collection layer. Our findings show the significantly enhanced photoelectrochemical activity of the composite photocathode with an improved photocurrent by three times (-0.9 mA cm-2 at 0.6 V vs. RHE) and the H2O2 formation up to 278 µmol L-1 with doubled faradaic efficiency. It is shown that these enhancements are due to the promoted charge carrier collection and kinetics. This work demonstrates the significant role of the charge collection layer in improving the collection and usage of photocarriers to accelerate the application of solar-to-fuel conversion.

17.
J Agric Food Chem ; 70(1): 184-195, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35016506

RESUMO

The mechanisms of coffee against Parkinson disease (PD) remained incompletely elucidated. Numerous studies suggested that gut microbiota played a crucial role in the pathogenesis of PD. Here, we explored the further mechanisms of coffee against PD via regulating gut microbiota. C57BL/6 mice were intraperitoneally injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to induce a PD mouse model, then treated with coffee for 4 consecutive weeks. Behavioral tests consisting of the pole test and beam-walking test were conducted to evaluate the motor function of mice. The levels of tyrosine hydroxylase (TH) and α-synuclein (α-syn) were assessed for dopaminergic neuronal loss. The levels of occludin, glial fibrillary acidic protein (GFAP), Bcl-2, Bax, cleaved caspase-3, and cytochrome c (Cyt c) were detected. Moreover, microbial components were measured by 16s rRNA sequencing. Our results showed that coffee significantly improved the motor deficits and TH neuron loss, and reduced the level of α-syn in the MPTP-induced mice. Moreover, coffee increased the level of BBB tight junction protein occludin and reduced the level of astrocyte activation marker GFAP in the MPTP-induced mice. Furthermore, coffee significantly decreased the levels of proapoptotic proteins, including Bax, cleaved caspase-3, and cytochrome c, while it increased the level of antiapoptotic protein Bcl-2, consequently preventing MPTP-induced apoptotic cascade. Moreover, coffee improved MPTP-induced gut microbiota dysbiosis. These findings suggested that the neuroprotective effects of coffee on PD were involved in the regulation of gut microbiota, which might provide a novel option to elucidate the effects of coffee on PD.


Assuntos
Microbioma Gastrointestinal , Fármacos Neuroprotetores , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Café , Modelos Animais de Doenças , Neurônios Dopaminérgicos , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S
18.
Nanomicro Lett ; 14(1): 15, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34870786

RESUMO

The recombination loss of photo-carriers in photocatalytic systems fatally determines the energy conversion efficiency of photocatalysts. In this work, an electrostatic field was used to inhibit the recombination of photo-carriers in photocatalysts by separating photo-holes and photo-electrons in space. As a model structure, (010) facet-exposed BiVO4 nanowires were grown on PDMS-insulated piezo-substrate of piezoelectric transducer (PZT). The PZT substrate will generate an electrostatic field under a certain stress, and the photocatalytic behavior of BiVO4 nanowires is influenced by the electrostatic field. Our results showed that the photocatalytic performance of the BiVO4 nanowires in CO2 reduction in the negative electrostatic field is enhanced to 5.5-fold of that without electrostatic field. Moreover, the concentration of methane in the products was raised from 29% to 64%. The enhanced CO2 reduction efficiency is mainly attributed to the inhibited recombination loss of photo-carriers in the BiVO4 nanowires. The increased energy of photo-carriers and the enhanced surface absorption to polar molecules, which are CO in this case, were also play important roles in improving the photocatalytic activity of the photocatalyst and product selectivity. This work proposed an effective strategy to improve photo-carriers separation/transfer dynamics in the photocatalytic systems, which will also be a favorable reference for photovoltaic and photodetecting devices.

19.
Opt Lett ; 46(19): 4726-4729, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598184

RESUMO

A four-channel coarse wavelength division multiplexing (CWDM) (de)multiplexer on a thin film lithium niobate-silicon rich nitride hybrid platform has been designed, fabricated, and experimentally measured. Enabled by cascaded multimode waveguide Bragg gratings, the (de)multiplexer has a box-like spectral response, wide 1-dB bandwidth (10 nm), low excess loss (<1.08dB), and low channel cross talk (<-18dB). The central wavelengths of the (de-)multiplexer are 1531/1551/1571/1591 nm, which align to the wavelength grids stipulated by the standard ITU-T G.694.2.

20.
Opt Lett ; 46(13): 3179-3182, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197410

RESUMO

A four-mode (de-)multiplexer with transverse electric field light (TE0-TE3) is experimentally demonstrated on a thin film lithium niobate-silicon rich nitride hybrid platform. Enabled by cascaded asymmetrical directional couplers, a (de-)multiplexer with low insertion loss (0.38 dB to 1.6 dB) and low cross talk (-18.46dB to -20.43dB) is obtained at 1550 nm. All channels have cross talk <-16dB from 1480 nm to 1580 nm. The transmission of 4×50 Gbps on-off keying signals is experimentally achieved on the proposed (de-)multiplexer. Experimental results show that the proposed (de-)multiplexer is a promising approach to enhance the transmission capacity in thin film lithium niobate based photonics integrated circuits.

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