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1.
Heliyon ; 10(6): e27555, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38545225

RESUMO

Proton Exchange Membrane Fuel Cells (PEMFCs) are promising sources of clean and renewable energy, but their performance and efficiency depend on an accurate modeling and identification of their system parameters. However, existing methods for PEMFC modeling suffer from drawbacks, such as slow convergence, high computational cost, and low accuracy. To address these challenges, this research work proposes an enhanced approach that combines a modified version of the SqueezeNet model, a deep learning architecture that reduces the number of parameters and computations, and a new optimization algorithm called the Modified Transient Search Optimization (MTSO) Algorithm, which improves the exploration and exploitation abilities of the search process. The proposed approach is applied to model the output voltage of the PEMFC under different operating conditions, and the results are compared with empirical data and two other state-of-the-art methods: Gated Recurrent Unit and Improved Manta Ray Foraging Optimization (GRU/IMRFO) and Grey Neural Network Model integrated with Particle Swarm Optimization (GNNM/PSO). The comparison shows that the proposed approach achieves the lowest Sum of Squared Errors (SSE) and the highest accuracy, demonstrating its superiority and effectiveness in PEMFC modeling. The proposed approach can facilitate the optimal design, control, and monitoring of PEMFC systems in various applications.

2.
J Plast Reconstr Aesthet Surg ; 86: 72-78, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37716252

RESUMO

BACKGROUND: The predictability and concordance between simulated and actual outcomes in rhinoplasty are uncertain. Here, we introduce a suture positioning technique (SPT), a simple and low-cost method to minimize the gap between the simulated and actual outcomes of rhinoplasty. METHODS: Seventy patients were enrolled in this study between January 2018 and January 2021. Preoperative simulations were performed using Adobe Photoshop. The control group underwent surgery using simulation and intuition. In the SPT group, sutures were used to assist in the preoperative identification of the ideal nasal tip position. The SPT effectiveness was tested by measuring the nasal parameters and using the patient's subjective satisfaction questionnaire at T1 (Time 1, immediately postoperatively) and T2 (Time 2, at least 1 year postoperatively). RESULTS: The intraclass correlation coefficient test showed a satisfactory correlation between simulation and postoperative outcomes in both groups. However, the SPT group had a higher correlation than the control group, especially for the nasal length (16% higher at T1 and 15% higher at T2). The mean absolute difference (MAD) between the outcomes and simulation indicated that the MAD of nasal tip projection between T2 and simulation and MAD of nasal length between T1 (or T2) and simulation were statistically significant between groups. Additionally, the SPT group was more satisfied with the postoperative outcomes and were consistent with the preoperative simulation. CONCLUSION: This study demonstrated the effectiveness of SPT in intraoperative quality control. This technique may be adopted by surgeons to achieve good concordance between simulated and actual surgical outcomes.


Assuntos
Rinoplastia , Humanos , Rinoplastia/métodos , Resultado do Tratamento , Estética , Nariz/cirurgia , Suturas , Septo Nasal/cirurgia
3.
Ultrasonics ; 132: 106988, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37003206

RESUMO

Surface acoustic wave (SAW) filter with a low insertion loss (IL) of 4.415 dB has been demonstrated on Carbon-doped semi-insulating c-plane bulk GaN without external lumped element matching. The center frequency, 3 dB bandwidth, out-of-band attenuation, return loss of the filter are 477.05 MHz, 0.308 MHz, 32.5 dB, and -9.72 dB, respectively. The electromechanical coupling coefficient (Kt2), and temperature coefficient of frequency (TCF) of the filter are 0.21 % and -26.0 ppm/°C, respectively. The impact of the number of interdigital transducers (NIDT) and acoustic propagation direction on filter performance has been studied. The IL of filters reduces from 16.07 dB to 4.415 dB with the increase of NIDT from 50 to 150 due to the enhanced acoustic superposition. The numerical distribution of elastic stiffness ([cij]), and piezoelectric constants ([eik]) of GaN has been calculated in Euler angle space, indicating that they are isotropic on c-plane. The small performance difference of filters along the m- and a-direction on c-plane bulk GaN can be attributed to the small offset angle of 0.5° of the bulk GaN wafer or IDT quality variation.

4.
Micromachines (Basel) ; 12(6)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071834

RESUMO

AlGaN/GaN E/D-mode GaN inverters are successfully fabricated on a 150-mm Si wafer. P-GaN gate technology is applied to be compatible with the commercial E-mode GaN power device technology platform and a systematic study of E/D-mode GaN inverters has been conducted with detail. The key electrical characters have been analyzed from room temperature (RT) to 200 °C. Small variations of the inverters are observed at different temperatures. The logic swing voltage of 2.91 V and 2.89 V are observed at RT and 200 °C at a supply voltage of 3 V. Correspondingly, low/high input noise margins of 0.78 V/1.67 V and 0.68 V/1.72 V are observed at RT and 200 °C. The inverters also demonstrate small rising edge time of the output signal. The results show great potential for GaN smart power integrated circuit (IC) application.

5.
J Dermatolog Treat ; 32(2): 231-235, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31403357

RESUMO

BACKGROUND: Circular RNA ITCH has been proved as a tumor suppressor in several types of cancer. Genetic alterations are known to play important roles in melanoma development. However, the function of circular RNAs and the role of ITCH in melanoma are still hardly known. METHODS: We investigated the expression levels of ITCH and the correlation between ITCH expression and GLUT1 expression, which showed that ITCH was downregulated in melanoma tissues and inversely correlated with GLUT1. RESULTS: ITCH overexpression resulted in the downregulation of GLUT1 and suppressed glucose uptake in melanoma. GLUT1 overexpression promoted glucose uptake but failed to affect ITCH. ITCH overexpression resulted in increased, while GLUT1 overexpression resulted in decreased rate of melanoma cell proliferation. In addition, GLUT1 overexpression reduced the effects of ITCH overexpression on cell proliferation. CONCLUSIONS: We concluded that ITCH may downregulate GLUT1 and suppresses glucose uptake in melanoma to inhibit cancer cell proliferation.


Assuntos
Proliferação de Células , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Melanoma/patologia , Proteínas Repressoras/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Adulto , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Transportador de Glucose Tipo 1/genética , Humanos , Masculino , Melanoma/genética , Pessoa de Meia-Idade , RNA Circular/genética , RNA Circular/metabolismo , Proteínas Repressoras/genética , Ubiquitina-Proteína Ligases/genética
6.
Micromachines (Basel) ; 13(1)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35056205

RESUMO

The impact of device parameters, including AlN film thickness (hAlN), number of interdigital transducers (NIDT), and acoustic propagation direction, on the performance of c-plane AlN/sapphire-based SAW temperature sensors with an acoustic wavelength (λ) of 8 µm, was investigated. The results showed that resonant frequency (fr) decreased linearly, the quality factor (Q) decreased and the electromechanical coupling coefficient (Kt2) increased for all the sensors with temperature increasing from -50 to 250 °C. The temperature coefficients of frequency (TCFs) of sensors on AlN films with thicknesses of 0.8 and 1.2 µm were -65.57 and -62.49 ppm/°C, respectively, indicating that a reduction in hAlN/λ favored the improvement of TCF. The acoustic propagation direction and NIDT did not obviously impact the TCF of sensors, but they significantly influenced the Q and Kt2 of the sensors. At all temperatures measured, sensors along the a-direction exhibited higher fr, Q and Kt2 than those along the m-direction, and sensors with NIDT of 300 showed higher Q and Kt2 values than those with NIDT of 100 and 180. Moreover, the elastic stiffness of AlN was extracted by fitting coupling of modes (COM) model simulation to the experimental results of sensors along different directions considering Euler transformation of material parameter-tensors. The higher fr of the sensor along the a-direction than that along the m-direction can be attributed to its larger elastic stiffness c11, c22, c44, and c55 values.

7.
Reprod Domest Anim ; 55(5): 584-593, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32053743

RESUMO

As common overexpression of Aurora A in various tumours, much attention has focused on its function in inducing cancer, and its value in cancer therapeutics, considerably less is known regarding its role in the first cleavage division of mammalian embryos. Here, we highlight an indispensable role of Aurora A during the first mitotic division progression of pig embryos just after meiosis. The expression and spatiotemporal localization of Aurora A were initially assessed in pig embryos during the first mitotic division by Western blot analysis and indirect immunofluorescent staining. Then, the potential role of Aurora A was further evaluated using a highly selective Aurora A inhibitor, MLN8054, during this mitotic progression in pig embryos. Aurora A was found to express and exhibit a specific dynamic intracellular localization pattern during the first mitotic division in pig embryos. Aurora A was diffused in the cytoplasm at the prophase stage, and then exhibited a dynamic intracellular localization which was tightly associated with the chromosome and spindle dynamics throughout subsequent mitotic phases. Inhibition of Aurora A by MLN8054 treatment led to the failure of the first cleavage, with the majority of embryos being arrested in prophase of the mitotic division. Further subcellular structure examination showed that Aurora A inhibition not only led to the failure of spindle microtubule assembly, but also resulted in severe defects in chromosome condensation, accompanied by an obvious decrease in p-TACC3(S558) expression during the prophase of the first mitosis. Together, these results illustrated that Aurora A is crucial for both spindle assembly and chromosome condensation during the first mitotic division in pig embryos, and that the regulation of Aurora A may be associated with its effects on p-TACC3(S558) expression.


Assuntos
Aurora Quinase A/antagonistas & inibidores , Benzazepinas/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Mitose/efeitos dos fármacos , Animais , Cromossomos/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Fuso Acromático/efeitos dos fármacos , Suínos
8.
An Bras Dermatol ; 92(4): 474-477, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28954094

RESUMO

BACKGROUND:: Surgical sutures, wound tension, additional skin incisions and other factors may result in recurrence of tumor-like scar. OBJECTIVE:: To investigate the role of wound natural healing therapy in tumor-like hypertrophic scar. METHODS:: In this study, tumor-like hypertrophic scars of 47 cases were excised completely and the residual wounds were treated with natural healing. The short-term and long-term effects of treatment were evaluated. RESULTS:: All cases were successfully cured by natural healing therapy. The healing time of the maximum wound (80mm × 20mm) and the minimal wound (5mm× 5mm) was 25 days and 7 days respectively. The size of new skin scars ranged from 3mm to 11 mm. Clinical followed-up was performed in 34 cases for 36 months. Among them, no recurrence happened in 31 cases and new scar size ranged from 2mm to 8mm, while local recurrence happened in 3 cases whose scar size were less than 5 mm. STUDY LIMITATIONS:: The cure rate of the therapy was 91.2%. CONCLUSION:: The wound natural healing therapy is effective in treating tumor-like hypertrophic scar, which can prevent recurrence and has good cosmetic results.


Assuntos
Cicatriz Hipertrófica/cirurgia , Técnicas de Fechamento de Ferimentos , Cicatrização/fisiologia , Adolescente , Adulto , Idoso , Criança , Cicatriz Hipertrófica/patologia , Cicatriz Hipertrófica/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Período Pré-Operatório , Recidiva , Infecção da Ferida Cirúrgica/etiologia , Técnicas de Sutura/efeitos adversos , Suturas/efeitos adversos , Resultado do Tratamento , Adulto Jovem
9.
An. bras. dermatol ; 92(4): 474-477, July-Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-887001

RESUMO

Abstract: Background: Surgical sutures, wound tension, additional skin incisions and other factors may result in recurrence of tumor-like scar. Objective: To investigate the role of wound natural healing therapy in tumor-like hypertrophic scar. Methods: In this study, tumor-like hypertrophic scars of 47 cases were excised completely and the residual wounds were treated with natural healing. The short-term and long-term effects of treatment were evaluated. Results: All cases were successfully cured by natural healing therapy. The healing time of the maximum wound (80mm × 20mm) and the minimal wound (5mm× 5mm) was 25 days and 7 days respectively. The size of new skin scars ranged from 3mm to 11 mm. Clinical followed-up was performed in 34 cases for 36 months. Among them, no recurrence happened in 31 cases and new scar size ranged from 2mm to 8mm, while local recurrence happened in 3 cases whose scar size were less than 5 mm. Study Limitations: The cure rate of the therapy was 91.2%. Conclusion: The wound natural healing therapy is effective in treating tumor-like hypertrophic scar, which can prevent recurrence and has good cosmetic results.


Assuntos
Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Cicatrização/fisiologia , Cicatriz Hipertrófica/cirurgia , Técnicas de Fechamento de Ferimentos , Período Pós-Operatório , Recidiva , Infecção da Ferida Cirúrgica/etiologia , Suturas/efeitos adversos , Técnicas de Sutura/efeitos adversos , Resultado do Tratamento , Cicatriz Hipertrófica/patologia , Cicatriz Hipertrófica/prevenção & controle , Período Pré-Operatório
10.
J Antibiot (Tokyo) ; 63(11): 657-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20877368

RESUMO

The objective of this paper was to investigate the in vitro effects of fusidic acid combined with fosfomycin against methicillin-resistant Staphylococcus aureus (MRSA). In all, 196 MRSA strains isolated from three clinical specimens of human infections from hospitals in China were used in this study. The checkerboard method was used to determine whether combinations act synergistically against these strains. The susceptibility results for fusidic acid and fosfomycin were interpreted according to the guidelines of the Clinical and Laboratory Standards Institute. The combination of fusidic acid and fosfomycin demonstrated the following interactions: 87.76% (172/196) synergism, 12.24% (24/196) indifference and no antagonism was seen (minimum and maximum fractional inhibitory concentration index 0.14 and 0.75, respectively). Thus, combinations of fusidic acid and fosfomycin show synergism for most of the MRSA isolates tested in this study, and may be a future therapeutic alternative for infections caused by MRSA.


Assuntos
Antibacterianos/farmacologia , Fosfomicina/farmacologia , Ácido Fusídico/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/administração & dosagem , China , Sinergismo Farmacológico , Quimioterapia Combinada , Fosfomicina/administração & dosagem , Ácido Fusídico/administração & dosagem , Guias como Assunto , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia
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