RESUMEN
This case report illustrates the successful nonsurgical and nonextraction treatment of a 12-year-old boy with skeletal Class II deep bite malocclusion undergoing two-phase clear aligner treatment. During A6 mandibular advancement phase, Class II buccal segment relationship was corrected by differential forward growth of the mandible, unplanned distalization of maxillary posterior teeth, and unplanned mesialization of mandibular posterior teeth. The maxillary sagittal curve of occlusion was deepened, the mandibular curve of Spee was not fully levelled, and the maxillary arch experienced downward-backward rotation resulting in premature contact on anterior and posterior open bite. Buccal crown tipping of maxillary posterior teeth was observed after arch expansion. The forward growth of the mandible improved the skeletal relationship, and the advancement of the chin position and sagittal movements of the incisors altered the nose-lip-chin relationship, resulting in an improved profile of the patient. During refinement phase, the posterior open bite was corrected. The mandibular plane angle did not increase throughout the treatment. The patient was satisfied with the aesthetic and functional outcome.
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Maloclusión Clase II de Angle , Mordida Abierta , Aparatos Ortodóncicos Removibles , Masculino , Humanos , Niño , Mordida Abierta/diagnóstico por imagen , Mordida Abierta/terapia , Estética Dental , Mandíbula/cirugía , Maloclusión Clase II de Angle/terapia , Maloclusión Clase II de Angle/cirugía , Técnicas de Movimiento Dental , Cefalometría/métodosRESUMEN
Material-enhanced heterogeneous peroxymonosulfate (PMS) activation for degradation of antibiotic in water has attracted intensive attention. However, one challenge is the electron transfer efficiency from the material to PMS for reactive oxygen species (ROS) production. Considering that the B-sites of perovskite oxides are closely associated with the catalytic performance, partial substitution of the B-sites of perovskite oxides can enhance the redox cycle of metals. Consequently, adjusting the ratio of each element at the B site can introduce oxygen vacancies on the surface of perovskite. Herein, a method was developed in which manganese (Mn) partially substitutes B-sites to modify surface properties of SrCoO2.52 perovskite oxides, resulting in the enhancement of catalytic activity. In degradation kinetics studies using SrCoMnO3-δ-0.5/PMS (SrCoMnO3-δ-0.5 denotes that the molar substitution of Mn at the B site of SrCoO2.52 perovskite oxide is 0.5) reaction system and sulfamethoxazole (SMX) as the target pollutant, it was found that the reaction rate constant (kobs) is 0.287 min-1 which is 2.4 times that of SrCoO2.52/PMS system. Experimental and theoretical analyses revealed that Mn-O covalent bonding governs the intrinsic catalytic activity of SrCoMnO3-δ-0.5 perovskite oxides. The Mn sites exhibits stronger adsorption energy with PMS than the Co sites, facilitating the breaking of O-O bond. Simultaneously, oxygen vacancies and surface adsorbed oxygen species have a synergistic effect for PMS adsorption. This work can provide a potential route in developing advanced catalysts based on manipulation of the B-sites of perovskite oxides for PMS activation.
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Contaminantes Ambientales , Manganeso , Especies Reactivas de Oxígeno , Peróxidos/química , Óxidos/química , Sulfametoxazol/química , Oxígeno , Agua , AntibacterianosRESUMEN
INTRODUCTION: The objectives of this study were to evaluate the clinical efficacy of SmartTrack aligner in rotational movement of the anterior tooth by 15°-30°, and to analyze the factors influencing anterior tooth rotational movement. METHODS: A total of 212 teeth, including 4 tooth types (maxillary central incisor, maxillary lateral incisor, mandibular central incisor, and mandibular canine) that require anterior tooth rotational movement by 15°-30° were selected from 123 patients, with a mean age of 25.6 years. Rotational movements were calculated from the superimposition of the initial and predicted models (predicted rotational movement) and from the superimposition of the initial and achieved models (achieved rotational movement) using the best-fit alignment tool in NX Imageware. The difference between the predicted and achieved rotational movements (DPARM) was calculated. Univariate analysis, categorical regression analysis, and subgroup analysis were performed on 7 variables: age, gender, tooth type, predicted rotational movement, attachment type, interproximal reduction (IPR), and the total number of active aligners. RESULTS: The mean DPARM when the anterior tooth was rotated 15°-30° was 4.46° (range, -3.52° to 25.28°). Regression analysis showed that the patient's age, IPR, tooth type, and predicted rotational movement affected DPARM (P <0.01). CONCLUSIONS: Factors influencing the DPARM of the anterior tooth include the patient's age, tooth type, the magnitude of the predicted rotational movement, and whether or not IPR was prescribed.
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Maloclusión , Aparatos Ortodóncicos Removibles , Humanos , Rotación , Resultado del Tratamiento , Técnicas de Movimiento DentalRESUMEN
Dementia has been cited as a critical public health risk in the contemporary world, while few empirical researchers try to reveal the casual relationship between air pollutant concentrations (APCs) and dementia, especially given the increasing prevalence of air pollution on a global scale. Accordingly, this paper tries to infer the causal relationship between APCs and dementia. The 59,605 valid data was compiled through a combination of the statistic from the China Family Panel Study, China Environmental Statistics Yearbook, World Meteorological Association and China National Bureau of Statistics. The RD design of this study utilizes the discontinuous variation in APCs and dementia as one crosses the Huai River boundary, which is an arbitrary heating policy that causes the significant difference in APCs between the north and south of China. We used stata17.0 to analyze the data. The results of the RD regression indicated that a 100 µ g/m3 rise in APCs led to an increase of 42.4% in the hazard ratio of suffering dementia (Coeff=-0.58, SD= 0.23, P < 0.05). Meanwhile, heterogeneous models revealed that the hazard ratio of suffering dementia by APCs was more significant in the older compared to younger (coeff= 1.35 vs coeff= 1.55, P < 0.05), male compared to female (coeff= 1.62 vs coeff= 0.71, P < 0.05), smoking compared to non-smoke (coeff= 2.12 vs coeff= 0.93, P < 0.05), and thin groups compared to medium and obesity (coeff= 2.05 vs coeff= 1.22, coeff= 1.28, P < 0.05). In addition, the O3 and SO2 were the air pollutants with the highest (coeff= 1.54, P < 0.05) and lowest effects (coeff= 0.81, P < 0.05) on the hazard ratio of suffering dementia among the five APCs, respectively. And the robustness of the results was ensured by changing the RD bandwidth, polynomial order. The results indicated that APCs significantly induced the hazard ratio of suffering dementia of Chinese residents, which provides empirical evidence in supporting the Chinese government to invest more in combating air pollution and ensure the public health of Chinese residents.
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Contaminantes Atmosféricos , Contaminación del Aire , Demencia , Masculino , Femenino , Humanos , Material Particulado/análisis , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , China/epidemiologíaRESUMEN
Background: COVID-19 has influenced education systems worldwide, and significantly increased screen time for college students, posing a potential risk of myopia. In China, ninety percent of college students suffer from myopia. Excessive screen time changes college students' lifestyles, imposes potential health risks, and affects opportunities for employment. It is important to identify the potential correlation between screen time use and myopia among college students. Methods: This paper conducted a nationwide experiment using Chinese college students and set a multiple-mediator SEM model to analyze the potential correlation between screen time and myopia. The two mediators were sedentary behavior and physical activity, respectively. Results: We obtained three valuable conclusions as follows: First, there was no significant direct relationship between screen time and myopia among Chinese college students during the COVID-19 pandemic. Second, sedentary behavior and physical activity significantly predicted the increase/decrease of myopia among Chinese college students, respectively. Third, a serial multiple mediator that encompassed sedentary behavior and physical activity sequentially fully mediated the relationship between screen time and myopia. Conclusions: Although there was no directly significant relationship between screen time and myopia, screen time can indirectly influence the risk of suffering myopia by influencing sedentary behavior and physical activity. Our study demonstrates the need to prevent the potential influence of overuse of electronic devices on myopia in college students, especially during the COVID-19 pandemic.
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COVID-19 , Miopía , Humanos , Tiempo de Pantalla , Pandemias , COVID-19/epidemiología , Conducta Sedentaria , Miopía/epidemiologíaRESUMEN
Alzheimer's disease and related dementias are more prevalent in rural areas than in urban areas in China. This study aims to examine the role of dementia beliefs and knowledge in influencing dementia worry among rural adults in China. Data were generated in a cross-sectional survey of 577 participants. Hierarchical regression analyses found that both the beliefs and knowledge of dementia contributed to higher levels of dementia worry. The propensity score matching method affirmed the robustness of regression results. In addition, those aged 45-64 reported higher worry about dementia than those aged 65 or older, while being married was related to lower dementia worry. As one of the first kind studies that examined dementia worry in rural Chinese population, our findings suggest that policy and practice efforts should address cultural beliefs of dementia as they contributed to higher worry about dementia in rural areas.
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Enfermedad de Alzheimer , Población Rural , Adulto , Enfermedad de Alzheimer/epidemiología , Ansiedad , China/epidemiología , Estudios Transversales , HumanosRESUMEN
During the economic boom, China's government was mainly concerned with economic development; however, numerous environmental problems have arisen. Evidence suggests that Chinese individuals' pro-environmental behavior (PEB) is at a low level in Asia. However, it does not match their high-quality environmental knowledge. In this paper, the database of the Chinese General Social Survey was used to explore the correlation between environmental knowledge and PEB in a broader context. Subsequently, environmental perception and post-materialistic values (PMV) were taken as the mediator and moderator into structural equation modeling, and every variable kept robust and consistent through exploratory factor analysis. The empirical results indicated that: (i) individuals with higher environmental knowledge always show higher passion to PEB; (ii) environmental perception plays a partially mediating role between environmental knowledge and PEB; (iii) PMV moderate the formation of environmental behavior systematically; and (iv) compared with public counterpart, the relation between environmental knowledge and PEB is significantly higher in private environmental behavior. The study results could become the basis for the Chinese government and environmental NGOs to effectively spread environmental knowledge, advocate a post-materialistic lifestyle, and improve the authenticity of online media reports on environmental issues.