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1.
Front Plant Sci ; 15: 1387350, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38751836

RESUMEN

Introduction: Accurate detection of potato seedlings is crucial for obtaining information on potato seedlings and ultimately increasing potato yield. This study aims to enhance the detection of potato seedlings in drone-captured images through a novel lightweight model. Methods: We established a dataset of drone-captured images of potato seedlings and proposed the VBGS-YOLOv8n model, an improved version of YOLOv8n. This model employs a lighter VanillaNet as the backbone network in-stead of the original YOLOv8n model. To address the small target features of potato seedlings, we introduced a weighted bidirectional feature pyramid network to replace the path aggregation network, reducing information loss between network layers, facilitating rapid multi-scale feature fusion, and enhancing detection performance. Additionally, we incorporated GSConv and Slim-neck designs at the Neck section to balance accuracy while reducing model complexity. Results: The VBGS-YOLOv8n model, with 1,524,943 parameters and 4.2 billion FLOPs, achieves a precision of 97.1%, a mean average precision of 98.4%, and an inference time of 2.0ms. Comparative tests reveal that VBGS-YOLOv8n strikes a balance between detection accuracy, speed, and model efficiency compared to YOLOv8 and other mainstream networks. Specifically, compared to YOLOv8, the model parameters and FLOPs are reduced by 51.7% and 52.8% respectively, while precision and a mean average precision are improved by 1.4% and 0.8% respectively, and the inference time is reduced by 31.0%. Discussion: Comparative tests with mainstream models, including YOLOv7, YOLOv5, RetinaNet, and QueryDet, demonstrate that VBGS-YOLOv8n outperforms these models in terms of detection accuracy, speed, and efficiency. The research highlights the effectiveness of VBGS-YOLOv8n in the efficient detection of potato seedlings in drone remote sensing images, providing a valuable reference for subsequent identification and deployment on mobile devices.

2.
Sci Rep ; 13(1): 22378, 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38104203

RESUMEN

In this study, detrital zircon U-Pb geochronology, trace element and Hf isotopic compositional data from the Early-Middle Triassic clastic rocks in the eastern Sichuan Basin were obtained to distinguish the sediment provenance and constrain the timing of the initial collision between the South China and North China blocks. Detrital zircons from the Early Triassic Feixianguan Formation clastic rocks yield one major age peak at 2476 Ma and three minor age peaks at 1886, 802 and 304 Ma. These detrital zircons may be derived from the South China Block. Detrital zircons from the Early Triassic Jialingjiang Formation clastic rocks yield multiple age peaks at 979, 856, 392 and 269 Ma, indicating a mixed sediment provenance from the South China Block and Qinling Orogenic Belt. This is the first appearance of the detritus with the Qinling Orogenic Belt affinity in the eastern Sichuan Basin. Detrital zircons from the Middle Triassic Leikoupo Formation clastic rocks yield two centralized age peaks at 447 and ca. 245 Ma. These zircons may mainly be derived from the Qinling Orogenic Belt. The results indicate an abrupt change in the detrital zircon U-Pb provenance from the South China Block to the Qinling Orogenic Belt during the Early-Middle Triassic. Integrating the provenance change and other geological characteristics, we suggest that the initial collision in the eastern Qinling Orogenic Belt occurred in the Early Triassic.

3.
JMIR Mhealth Uhealth ; 6(5): e126, 2018 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-29792290

RESUMEN

BACKGROUND: The proliferation of mobile health apps has greatly changed the way society accesses the health care industry. However, despite the widespread use of mobile health apps by patients in China, there has been little research that evaluates the effect of mobile health apps on patient experience during hospital visits. OBJECTIVE: The purpose of our study was to examine whether the use of mobile health apps improves patient experience and to find out the difference in patient experience between users and nonusers and the characteristics associated with the users of these apps. METHODS: We used the Chinese Outpatient Experience Questionnaire to survey patient experience. A sample of 300 outpatients was randomly selected from 3 comprehensive public hospitals (3 tertiary hospitals) in Hubei province, China. Each hospital randomly selected 50 respondents from mobile health app users and 50 from nonusers. A chi-square test was employed to compare the different categorical characteristics between mobile health app users and nonusers. A t test was used to test the significance in continuous variables between user scores and nonuser scores. Multiple linear regression was conducted to determine whether the use of mobile health apps during hospital visits was associated with patient experience. RESULTS: The users and nonusers differed in age (χ22=12.2, P=.002), education (χ23=9.3, P=.03), living place (χ21=7.7, P=.006), and the need for specialists (χ24=11.0, P=.03). Compared with nonusers, mobile health app users in China were younger, better educated, living in urban areas, and had higher demands for specialists. In addition, mobile health app users gave significantly higher scores than nonusers in total patient experience scores (t298=3.919, P<.001), the 18 items and the 5 dimensions of physician-patient communication (t298=2.93, P=.004), health information (t298=3.556, P<.001), medical service fees (t298=3.991, P<.001), short-term outcome (t298=4.533, P<.001), and general satisfaction (t298=4.304, P<.001). Multiple linear regression results showed that the use of mobile health apps during hospital visits influenced patient experience (t289=3.143, P=.002). After controlling for other factors, it was shown that the use of mobile health apps increased the outpatient experience scores by 17.7%. Additional results from the study found that the self-rated health status (t289=3.746, P<.001) and monthly income of patients (t289=2.416, P=.02) influenced the patient experience as well. CONCLUSIONS: The use of mobile health apps could improve patient experience, especially with regard to accessing health information, making physician-patient communication more convenient, ensuring transparency in medical charge, and ameliorating short-term outcomes. All of these may contribute to positive health outcomes. Therefore, we should encourage the adoption of mobile health apps in health care settings so as to improve patient experience.

4.
Int J Qual Health Care ; 29(1): 40-46, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27836998

RESUMEN

OBJECTIVE: The objective of this study is to describe the development of the Outpatient Experience Questionnaire (OPEQ) and to assess the validity and reliability of the scale. DESIGN: Literature review, patient interviews, Delphi method and Cross-sectional validation survey. SETTING: Six comprehensive public hospitals in China. PARTICIPANTS: The survey was carried out on a sample of 600 outpatients. MAIN OUTCOME MEASURE(S): Acceptability of the questionnaire was assessed according to the overall response rate, item non-response rate and the average completion time. Correlation coefficients and confirmatory factor analysis were used to test construct validity. Delphi method was used to assess the content validity of the questionnaire. Cronbach's coefficient alpha and split-half reliability coefficient were used to estimate the internal reliability of the questionnaire. RESULTS: The overall response rate was 97.2% and the item non-response rate ranged from 0% to 0.3%. The mean completion time was 6 min. The Spearman correlations of item-total score ranged from 0.466 to 0.765. The results of confirmatory factor analysis showed that all items had factor loadings above 0.40 and the dimension intercorrelation ranged from 0.449 to 0.773, the goodness of fit of the questionnaire was reasonable. The overall authority grade of expert consultation was 0.80 and Kendall's coefficient of concordance W was 0.186. The Cronbach's coefficients alpha of six dimensions ranged from 0.708 to 0.895, the split-half reliability coefficient (Spearman-Brown coefficient) was 0.969. CONCLUSIONS: The OPEQ is a promising instrument covering the most important aspects which influence outpatient experiences of comprehensive public hospital in China. It has good evidence for acceptability, validity and reliability.


Asunto(s)
Pacientes Ambulatorios/psicología , Satisfacción del Paciente , Encuestas y Cuestionarios , China , Estudios Transversales , Análisis Factorial , Hospitales Públicos , Humanos , Psicometría , Reproducibilidad de los Resultados
5.
Med Hypotheses ; 74(1): 92-4, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19700246

RESUMEN

It is well known that the mechanism of action of chemotherapeutic drugs and their ability to induce multidrug resistance (MDR) are of relevance to cancer treatment. Although MDR is a multifactorial process, the main obstacle is the expression of multidrug-efflux pumps that lowers the intracellular drug levels. P-glycoprotein (P-gp) is the longest identified efflux pump. Thus, P-gp has been looked as a well established mediator of MDR and it became a therapeutic target for circumventing multidrug resistance. However, the mechanism of adjusting the expression of P-gp is not clear yet. The results of the effect of genetic polymorphism on P-gp expression and function remain conflicting. More recently, studies on the regulation of MDR1 has widened to examine the role of epigenetics and some new results were found to support the effect of epigenetic variance in vitro. It is hence hypothesized that epigenetic variants play more important roles than genetic polymorphism, thus adjusting the epigenetic factors could alter the expression of MDR, leading to the reverse of MDR. And it is further hypothesized that histone deacetylase inhibitors could be another strategy to overcome MDR. The mechanism may include a bidirectional modulation of P-gp by histone deacetylase inhibitors.


Asunto(s)
Resistencia a Múltiples Medicamentos/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Línea Celular Tumoral , Metilación de ADN , Epigénesis Genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Humanos , Modelos Biológicos , Modelos Genéticos , Modelos Teóricos , Polimorfismo Genético
6.
Pharmacogenomics ; 9(12): 1801-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19072639

RESUMEN

AIMS: To investigate the correlation between the methylation status in the MDR1 promoter region and the MDR1 genetic polymorphism. METHODS: A total of 194 unrelated subjects (105 men and 89 women) with a median age of 26 years were enrolled in this study. DNA was extracted and PCR-RFLP was performed for C1236T, C3435T and G2677T/A polymorphism genotyping. The combined bisulfite restriction analysis (COBRA) method was also performed to determine DNA methylation levels in the MDR1 promoter region. Genotype frequencies for the variants SNPs were assessed for deviation from Hardy-Weinberg equilibrium using the chi2 test. Nonparametric tests including Kruskal-Wallis method and the Mann-Whitney U test were used to compare the DNA methylation levels between different genotypes. RESULTS: The allelic frequency distribution of the C1236T, C3435T and G2677T/A was found to be in good agreement with previous reports. Our study revealed significant correlation between different genotypes of C3435T and G2677T/A, but there is no significant difference between the different genotypes of C1236T. CONCLUSION: A correlation between MDR1 genetic polymorphisms C3435T and G2677T/A, as well as haplotypes derived from C1236T, G2677T/A and C3435T, with methylation status of MDR1 promoter region was found in this study. Further investigations are needed to explore the molecular mechanism and clinical significance of this correlation.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Pueblo Asiatico/genética , Metilación de ADN , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Adulto , Interpretación Estadística de Datos , Epigénesis Genética , Femenino , Genotipo , Haplotipos , Humanos , Masculino , Adulto Joven
7.
J Environ Sci (China) ; 16(4): 651-5, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15495974

RESUMEN

Osmotic distillation (OD) was found to be a coupled process in membrane absorption (MA) for the treatment of high strength ammonia wastewater. As a result, ammonia could not be concentrated in absorption solution(AS) as expected. The inhibition of the coupled OD in MA process was investigated as well as various factors affecting the inhibition. The results indicated that the coupled OD can be effectively inhibited by heating concentrated solution and cooling dilute solution. It was also found that experimental minimum inhibition temperature difference(MITD) between concentrated and dilute solutions was different when using polyvinylidene fluoride(PVDF) and polypropylene(PP) membranes respectively, which could be ascribed to material properties, such as OD and membrane distillation (MD) coefficients of the membranes. Experimental MITDs were found to be higher than theoretical MITDs which were calculated using a simplified method.


Asunto(s)
Amoníaco/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Absorción , Amoníaco/química , Membranas Artificiales , Ósmosis
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