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1.
BMC Public Health ; 24(1): 1351, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769481

RESUMEN

BACKGROUND: Adolescent weight problems have become a growing public health concern, making early prediction of non-normal weight status crucial for effective prevention. However, few temporal prediction tools for adolescent four weight status have been developed. This study aimed to predict the short- and long-term weight status of Hong Kong adolescents and assess the importance of predictors. METHODS: A population-based retrospective cohort study of adolescents was conducted using data from a territory-wide voluntary annual health assessment service provided by the Department of Health in Hong Kong. Using diet habits, physical activity, psychological well-being, and demographics, we generated six prediction models for successive weight status (normal, overweight, obese and underweight) using multiclass Decision Tree, Random Forest, k-Nearest Neighbor, eXtreme gradient boosting, support vector machine, logistic regression. Model performance was evaluated by multiple standard classifier metrics and the overall accuracy. Predictors' importance was assessed using Shapley values. RESULTS: 442,898 Primary 4 (P4, Grade 4 in the US) and 344,186 in Primary 6 (P6, Grade 6 in the US) students, with followed up until their Secondary 6 (Grade 12 in the US) during the academic years 1995/96 to 2014/15 were included. The XG Boosts model consistently outperformed all other model in predicting the long-term weight status at S6 from P4 or P6. It achieved an overall accuracy of 0.72 or 0.74, a micro-averaging AUC of 0.92 or 0.93, and a macro-averaging AUC of 0.83 or 0.86, respectively. XG Boost also demonstrated accurate predictions for each predicted weight status, surpassing the AUC values obtained by other models. Weight, height, sex, age, frequency and hours of aerobic exercise were consistently the most important predictors for both cohorts. CONCLUSIONS: The machine learning approaches accurately predict adolescent weight status in both short- and long-term. The developed multiclass model that utilizing easy-assessed variables enables accurate long-term prediction on weight status, which can be used by adolescents and parents for self-prediction when applied in health care system. The interpretable models may help to provide the early and individualized interventions suggestions for adolescents with weight problems particularly.


Asunto(s)
Aprendizaje Automático , Humanos , Adolescente , Hong Kong , Masculino , Femenino , Estudios Retrospectivos , Peso Corporal , Ejercicio Físico , Obesidad Infantil
2.
J Esthet Restor Dent ; 35(4): 621-624, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36810946

RESUMEN

OBJECTIVE: To detail a technique for bonding periodontal splint precisely in a digital workflow. CLINICAL CONSIDERATIONS: Periodontal splinting can be considered to stabilize the mobile teeth, especially for mandibular anterior teeth. Reliable bonding of periodontal splints is a prerequisite for successful clinical performance. However, when bonding the indirect splint to place or making direct splint intraorally, there is a significant risk of mobile teeth drifting away from the splint. To guide accurate insertion of periodontal splint with no risk of displacement of mobile teeth, a guide device fabricated by digital workflow is introduced in this article. CONCLUSIONS: Periodontal compromised teeth can be provisionally fixed during splinting, with the help of the guided device, and precise bonding of the splint is readily accomplished by using such digital workflow. This technique is not only applicable to the lingual splints, but also suitable for the labial ones. CLINICAL SIGNIFICANCE: The use of a guided device, after being digitally designed and fabricated, enables to stabilize the mobile teeth, in case of any displacement during splinting. It is straightforward, and beneficial to reduce the risk of complications, such as debonding of the splint, and secondary occlusal trauma.


Asunto(s)
Ferulas Periodontales , Movilidad Dentaria , Humanos , Flujo de Trabajo , Movilidad Dentaria/terapia , Férulas (Fijadores)
3.
Sensors (Basel) ; 22(16)2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-36015947

RESUMEN

RGB-D salient object detection (SOD) demonstrates its superiority in detecting in complex environments due to the additional depth information introduced in the data. Inevitably, an independent stream is introduced to extract features from depth images, leading to extra computation and parameters. This methodology sacrifices the model size to improve the detection accuracy which may impede the practical application of SOD problems. To tackle this dilemma, we propose a dynamic knowledge distillation (DKD) method, along with a lightweight structure, which significantly reduces the computational burden while maintaining validity. This method considers the factors of both teacher and student performance within the training stage and dynamically assigns the distillation weight instead of applying a fixed weight on the student model. We also investigate the issue of RGB-D early fusion strategy in distillation and propose a simple noise elimination method to mitigate the impact of distorted training data caused by low quality depth maps. Extensive experiments are conducted on five public datasets to demonstrate that our method can achieve competitive performance with a fast inference speed (136FPS) compared to 12 prior methods.


Asunto(s)
Algoritmos , Superóxido Dismutasa , Humanos
4.
Org Biomol Chem ; 15(19): 4072-4076, 2017 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-28443892

RESUMEN

Novel BODIPYs undergoing excited state intramolecular proton transfer are reported. The molecules afford NIR emission with a large Stokes shift and possess a free hydroxyl unit that is easy to functionalize, allowing the dyes to be exploited as a valuable scaffold in probe design.

5.
Polymers (Basel) ; 14(14)2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35890611

RESUMEN

BACKGROUND: In this study, we evaluated the effect of periodontal splints made from different materials on the stress distributions in compromised periodontal tissues and cement layers, using a computer simulation of mastication. METHODS: Twenty-five 3D models were created for a segment of mandibular teeth with different periodontal splints bilaterally extended to the canines. The models were divided into five groups according to the different materials and thicknesses (mm) of the splints: the non-splinted group, PEEK 0.7 group, PEEK 1.0 group, FRC group, and titanium group. Each group was subdivided based on five bone loss levels. Tooth 41 of each model was subjected to vertical and oblique (θ = 45°) static loads of 100 N, respectively, onto the incisal edge. The von Mises stresses and maximum principal stress were analyzed using Abaqus software. RESULTS: Oblique loading resulted in higher stresses on periodontal tissues, cement layers, and splints than those caused by vertical loading. The lower the supporting bone level, the greater the stress difference between the splinted groups and the non-splinted group. In model 133,331, with severe bone loss, the maximum von Mises stress values on the alveolar bone in tooth 41 under oblique loading dramatically decreased from 406.4 MPa in the non-splinted group to 28.62 MPa in the PEEK group and to 9.59 MPa in the titanium group. The four splinted groups presented similar stress distributions in periodontal tissues. The lowest stress level on the splint was observed in the PEEK 0.7 group, and the highest stress level was transferred to the cement layer in this group. Stress concentrations were primarily exhibited at the connectors near the load-carrying area. CONCLUSIONS: The tested splinted groups were all effective in distributing the loads on periodontal tissues around splinted teeth with similar patterns. Using splinting materials with low elastic moduli reduced the stress concentration at the splint connectors, whereas the tensile stress concentration was increased in the cement layer. Thus, the use of adhesive cement with a higher elastic modulus is recommended when applying less rigid PEEK splints.

6.
Polymers (Basel) ; 14(21)2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36365609

RESUMEN

The high-performance thermoplastic polyetheretherketone (PEEK) has excellent mechanical properties, biocompatibility, chemical stability, and radiolucency. The present article comprehensively reviews various applications of PEEK in removable dental prostheses, including in removable partial dentures (RPDs) (frameworks and clasps), double-crown RPDs, and obturators. The clinical performance of PEEK in removable dental prostheses is shown to be satisfactory and promising based on the short-term clinical evidence and technical complications are scarce. Moreover, the accuracy of RPDs is a vital factor for their long-term success rate. PEEK in removable dental prostheses is fabricated using the conventional lost-wax technique and CAD/CAM milling, which produces a good fit. Furthermore, fused deposition modeling is considered to be one of the most practical additive techniques. PEEK in removable prostheses produced by this technique exhibits good results in terms of the framework fit. However, in light of the paucity of evidence regarding other additive techniques, these manufacturers cannot yet be endorsed. Surface roughness, bacterial retention, color stability, and wear resistance should also be considered when attempting to increase the survival rates of PEEK removable prostheses. In addition, pastes represent an effective method for PEEK polishing to obtain a reduced surface roughness, which facilitates lower bacterial retention. As compared to other composite materials, PEEK is less likely to become discolored or deteriorate due to wear abrasion.

7.
Zhong Yao Cai ; 34(12): 1894-7, 2011 Dec.
Artículo en Zh | MEDLINE | ID: mdl-22500427

RESUMEN

OBJECTIVE: To study the fat-soluble components in different parts of Pileostegia viburnoides. METHODS: The fat-soluble components in different parts of Pileostegia viburnoides were extracted by Herbal Blitzkrieg Extractor (HBE), and its constituents were analyzed by GC-MS. RESULTS: 37 compounds from the stems, 14 compounds from the leaves were separated and identified. The ratios of identification of total compounds were 90. 63% and 81.61%, respectively. CONCLUSION: This result provides the scientific basis for ex-ploiting resources of Miao ethnomedicine Pileostegia viburnoides.


Asunto(s)
Ácidos Grasos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Saxifragaceae/química , Tecnología Farmacéutica/métodos , Ésteres/análisis , Grasas/análisis , Ácido Linoleico/análisis , Medicina Tradicional , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Ácido Palmítico/análisis , Hojas de la Planta/química , Tallos de la Planta/química
8.
PLoS Negl Trop Dis ; 15(2): e0009056, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33626051

RESUMEN

While many studies have focused on identifying the association between meteorological factors and the activity of COVID-19, we argue that the contribution of meteorological factors to a reduction of the risk of COVID-19 was minimal when the effects of control measures were taken into account. In this study, we assessed how much variability in COVID-19 activity is attributable to city-level socio-demographic characteristics, meteorological factors, and the control measures imposed. We obtained the daily incidence of COVID-19, city-level characteristics, and meteorological data from a total of 102 cities situated in 27 provinces/municipalities outside Hubei province in China from 1 January 2020 to 8 March 2020, which largely covers almost the first wave of the epidemic. Generalized linear mixed effect models were employed to examine the variance in the incidence of COVID-19 explained by different combinations of variables. According to the results, including the control measure effects in a model substantially raised the explained variance to 45%, which increased by >40% compared to the null model that did not include any covariates. On top of that, including temperature and relative humidity in the model could only result in < 1% increase in the explained variance even though the meteorological factors showed a statistically significant association with the incidence rate of COVID-19. In conclusion, we showed that very limited variability of the COVID-19 incidence was attributable to meteorological factors. Instead, the control measures could explain a larger proportion of variance.


Asunto(s)
COVID-19/epidemiología , Ambiente , Control de Infecciones/métodos , Conceptos Meteorológicos , China/epidemiología , Humanos , Incidencia , Estudios Retrospectivos , SARS-CoV-2/aislamiento & purificación
9.
J Mater Chem B ; 8(28): 6013-6016, 2020 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-32633308

RESUMEN

We present an approach for constructing a H2S-specific nanoprobe by the entrapment of a small molecule probe within the hydrophobic interior of surface cross-linked micelles (SCMs), endowing the designed nanoprobes with good water solubility and biocompatibility. Importantly, the obtained nanoprobes displayed good responsiveness to H2S in both ratiometric fluorescence and light-up NIR emission modes, thus enabling accurate identification of H2S-rich colorectal cancer cells.


Asunto(s)
Materiales Biocompatibles/química , Neoplasias Colorrectales/diagnóstico por imagen , Colorantes Fluorescentes/química , Sulfuro de Hidrógeno/análisis , Nanopartículas/química , Imagen Óptica , Materiales Biocompatibles/síntesis química , Colorantes Fluorescentes/síntesis química , Células HCT116 , Humanos , Micelas , Tamaño de la Partícula , Propiedades de Superficie , Agua/química
10.
PeerJ ; 8: e10350, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33194456

RESUMEN

BACKGROUND: Monitoring the reproduction number (Rt ) of the disease could help determine whether there is sustained transmission in a population, but areas with similar epidemic trends could have different transmission dynamics given the risk from imported cases varied across regions. In this study, we examined the Rt of coronavirus disease 2019 (COVID-19) by taking different dynamics of imported cases into account and compared the transmissibility of COVID-19 at different intervention periods in Hangzhou and Shenzhen. METHODS: We obtained the daily aggregated counts of laboratory-confirmed imported and local cases of COVID-19 infections in Hangzhou and Shenzhen from January 1 to March 13, 2020. Daily Rt and piecewise Rt before and after Wuhan lockdown were estimated, accounting for imported cases. RESULTS: Since the epidemic of COVID-19 in Shenzhen was dominated by imported cases, Rt was around 0.1 to 0.7 before the Wuhan lockdown. After the lockdown of Wuhan and the initialization of measures in response to the outbreak, local transmission was well-controlled as indicated by a low estimated value of piecewise Rt , 0.15 (95% CI [0.09-0.21]). On the contrary, Rt obtained for Hangzhou ranged from 1.2 to 4.9 with a piecewise Rt of 2.55 (95% CI [2.13-2.97]) before the lockdown of Wuhan due to the surge in local cases. Because of the Wuhan lockdown and other outbreak response measures, Rt dropped below unity in mid-February. CONCLUSIONS: Even though Shenzhen had more cases than Hangzhou, local transmission did not sustain probably due to limited transmission from imported cases owing to the reduction in local susceptibles as residents left the city during Chunyun. The lockdown measures and local outbreak responses helped reduce the local transmissibility.

11.
Int J Infect Dis ; 96: 128-130, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32417744

RESUMEN

Owing to the frequent travel connections between Wuhan and Zhejiang, Zhejiang was the third worst-affected province in China with 1,205 cases confirmed before 26 February 2020. The transmissibility of the 2019 novel coronavirus disease was monitored in Zhejiang, accounting for the transmissions from imported cases. Even though Zhejiang was one of the worst-affected provinces, an interruption of disease transmission (i.e. instantaneous reproduction numbers <1) was observed in early/mid-February after a comprehensive set of interventions combating the outbreak.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/transmisión , Neumonía Viral/transmisión , Número Básico de Reproducción , COVID-19 , China/epidemiología , Infecciones por Coronavirus/epidemiología , Humanos , Pandemias , Neumonía Viral/epidemiología , SARS-CoV-2
12.
J Chromatogr Sci ; 54(2): 206-15, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26472809

RESUMEN

Xiong Ma Tang (XMT), one of the ancient herbal prescriptions, has been used in treatment of migraine disease. In this study, efficient high-performance liquid chromatographic fingerprints were developed for identification of 11 major marker components, named 1-(ß-D-ribofuranosyl)-1H-1,2,4-triazone, gastrodin, ligustrazine, 3,4-bihydroxy benzaldehyde, p-hydroxy benzaldehyde, p-hydroxybenzoic acid, benzoic acid, vanillin, ferulic acid, caffeic acid and senkyunolide I, respectively, in XMT and three related preparations. The analysis of 11 marker compounds was carried out using a Kromasil C18 reserved-phase column (5 µm, 4.6 × 250 mm) and gradient elution with methanol and aqueous phosphoric acid (0.1%, v/v). The flow rate was 1.0 mL/min and the detector wavelength was set at 276 nm. Mean chromatograms and correlation coefficients of samples were calculated by the software "Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine". The correlation coefficients of XMT and three related preparations ranged from 0.935 to 0.986, 0.909 to 0.949, 0.900 to 0.926 and 0.937 to 0.988, respectively. It was the first time 11 peaks of XMT and three related preparations were identified by comparing with standard compounds. These results have shown that the developed method was efficient for the quality evaluation of XMT and its related preparations.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Control de Calidad , Espectrometría de Masa por Ionización de Electrospray
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