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1.
Sensors (Basel) ; 23(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37960544

RESUMO

The upcoming Salinity Satellite, scheduled for launch in 2024, will feature the world's first phased array radar scatterometer. To validate its capability in measuring ocean surface backscatter coefficients, this paper conducts an in-depth analysis of the onboard verification flight test for the Salinity Satellite scatterometer. This paper provides a detailed introduction to the system design of the Salinity Satellite scatterometer, which utilizes phased array radar technology and digital beamforming techniques to achieve accurate measurements of sea surface scattering characteristics. The paper elaborates on the derivation of backscatter coefficients, system calibration, and phase amplitude correction for the phased array scatterometer. Furthermore, it describes the process of the onboard calibration flight test. By analyzing internal noise signals, onboard calibration signals, and external noise signals, the stability and reliability of the scatterometer system are validated. The experiment covers both land and ocean observations, with a particular focus on complex sea surface conditions in nearshore areas. Through the precise analysis of backscatter coefficients, the paper successfully distinguishes the different backscatter coefficient characteristics between ocean and land. The research results effectively demonstrate the feasibility of the Salinity Satellite scatterometer for measuring backscatter coefficients in a phased array configuration, as well as its outstanding performance in complex marine environments.

2.
Bioengineering (Basel) ; 9(12)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36550983

RESUMO

Apical Lesions, one of the most common oral diseases, can be effectively detected in daily dental examinations by a periapical radiograph (PA). In the current popular endodontic treatment, most dentists spend a lot of time manually marking the lesion area. In order to reduce the burden on dentists, this paper proposes a convolutional neural network (CNN)-based regional analysis model for spical lesions for periapical radiographs. In this study, the database was provided by dentists with more than three years of practical experience, meeting the criteria for clinical practical application. The contributions of this work are (1) an advanced adaptive threshold preprocessing technique for image segmentation, which can achieve an accuracy rate of more than 96%; (2) a better and more intuitive apical lesions symptom enhancement technique; and (3) a model for apical lesions detection with an accuracy as high as 96.21%. Compared with existing state-of-the-art technology, the proposed model has improved the accuracy by more than 5%. The proposed model has successfully improved the automatic diagnosis of apical lesions. With the help of automation, dentists can focus more on technical and medical diagnoses, such as treatment, tooth cleaning, or medical communication. This proposal has been certified by the Institutional Review Board (IRB) with the certification number 202002030B0.

3.
J Ethnopharmacol ; 269: 113716, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33352238

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Jiaolong capsule (JLC) was approved for the therapy of gastrointestinal diseases by the State Food and Drug Administration (SFDA) of China. It has a satisfactory curative effect in the treatment of patients with inflammatory bowel disease, however, the mechanism remains to be elucidated. AIM OF THE STUDY: In current study, the effects and possible mechanisms of JLC on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis were investigated. MATERIALS AND METHODS: Sulfasalazine and JLC were administrated orally and initialized 6 h after TNBS enema, once a day for seven consecutive days. The effect of JLC on intestinal microbial populations and LPS/TLR-4/NF-κB pathway was observed and assessed. Thirty female SD rats were distributed into six groups randomly and equally, namely, control, TNBS, TNBS + sulfasalazine (625 mg/kg), and TNBS + three different doses of JLC (25, 50, and 100 mg/kg) groups. RESULTS: The effect of JLC on restoring normal structures of colorectum and repairing colonic damage were superior to that of sulfasalazine. JLC showed a positive effect in re-balancing intestinal bacteria population of colitis, and suppressed the activation of LPS/TLR-4/NF-κB pathway. CONCLUSION: The results suggest that JLC demonstrated a beneficial effect on treating colitis in a rat model. The possible mechanisms may be through the regulatory effect of intestinal commensal bacteria and down-regulation of LPS/TLR-4/NF-κB pathway.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Fármacos Gastrointestinais/farmacologia , Substâncias Protetoras/farmacologia , Ácido Acético/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Colite Ulcerativa/induzido quimicamente , Colo/efeitos dos fármacos , Colo/patologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Fármacos Gastrointestinais/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos Endogâmicos ICR , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Dor/induzido quimicamente , Dor/tratamento farmacológico , Substâncias Protetoras/química , Substâncias Protetoras/uso terapêutico , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sulfassalazina/farmacologia , Sulfassalazina/uso terapêutico , Receptor 4 Toll-Like/biossíntese , Receptor 4 Toll-Like/efeitos dos fármacos , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Ácido Trinitrobenzenossulfônico/toxicidade
4.
PLoS One ; 14(11): e0225644, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31770413

RESUMO

BACKGROUND: High levels of suspended particulate matters (PMs) and bioaerosols are created by dental procedures. The present study aimed to evaluate the size and concentration of PMs produced by drilling and grinding teeth, and to assess the efficiency of central vacuum system and protective masks for the removal of PMs. METHODS: A total of 20 extracted permanent teeth were collected. A novel experimental system and particle counter were used to evaluate the PMs produced by dental procedures and the PM removal efficiency of a central vacuum system and surgical/N95 masks. RESULTS: The number concentration of total PMs produced by drilling and grinding teeth was significantly higher than the indoor background concentration. The average aerodynamic diameter of particle was generally less than 1 µm. The average number concentration of ultrafine particles was 2.1x1011 particles/m3 during tooth drilling and grinding. The efficiency of the central vacuum system was 35.74% for PM≥0.5 and 35.41% for PM10. For PM≥0.5, the ratios of inside and outside masks were 0.8-1.34 without vacuum and 1.18-1.36 with vacuum. No difference was found with the use of surgical/N95 masks during dental therapy, with or without vacuum use. CONCLUSIONS: High levels of PMs were found during tooth drilling and grinding procedures, especially among PM1. The PM removal efficiency of a central vacuum system and surgical/N95 masks were limited.


Assuntos
Raspagem Dentária , Máscaras , Material Particulado/análise , Poluição do Ar em Ambientes Fechados/análise , Humanos , Tamanho da Partícula , Material Particulado/isolamento & purificação , Dispositivos de Proteção Respiratória , Vácuo
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