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A series of Ca3Al2Ge3O12: xDy3+, yEu3+ phosphors were successfully prepared by the high-temperature solid-phase method. The phase and morphology of the phosphors were studied by means of Rietveld refinement and scanning electron microscopy. The results show that the phase is pure, and the crystal structure is the Ia3Ì d space group. In the Ca3Al2Ge3O12: xDy3+ phosphors, using 380 nm excitation, phosphors showed blue (4F9/2 â 6H15/2) and yellow (4F9/2 â 6H13/2) emission peaks at 481 and 581 nm, respectively. In Ca3Al2Ge3O12: xDy3+, yEu3+ phosphors, the energy transfer was inferred by the spectrum overlap of Dy3+ and Eu3+, and the lifetime attenuation was analyzed from the perspective of dynamics; finally, the band gap structure of the phosphors was analyzed by combining diffuse reflection spectra with the first principle, and the energy transfer mechanism and luminescence mechanism were elaborated by combining theory and practice. The transition from blue white light to red light can be achieved by tuning the range of y in Ca3Al2Ge3O12: 0.015Dy3+, yEu3+. Wherein, when y = 0.07, phosphors, the chromaticity coordinate of warm white CIE is (0.3932, 0.3203), the color temperature is 3093 K, and the warm white light is synthesized. The thermal stability of the synthesized warm white phosphors is 90.1% (423 K), the thermal sensing factors are Samax = 5.51 × 10-4 K-1 (303 K) and Srmax = 0.0359% K-1 (303 K), and the actual quantum efficiency is IQE = 52.48%. These results prove that Ca3Al2Ge3O12: Dy3+, Eu3+ have good application prospects as single-component warm w-LED devices.
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OBJECTIVES: The aims of this study were to evaluate the effect of related factors that influence orthodontic treatment time and to identify the predictors of orthodontic treatment duration in a Chinese population. MATERIALS AND METHODS: Information for 29 sociodemographic, malocclusion and orthodontic treatment characteristics was collected. Patients were divided into two groups: the duration ≤24 months group and duration >24 months group. The treatment dates of the initial visit and end of orthodontic treatment were obtained to calculate duration. The data were subjected to univariate and multivariate logistic regression modelling to quantify the association between characteristics and the treatment duration; odds ratios (ORs) and 95% confidence intervals (95% CIs) are reported. RESULTS: Of 2120 patients, 704 patients (mean age, 15.9 ± 6.0 years) were included. Age, extraction, Bolton ratio (overall), rotated teeth, overjet and crowding (lower arch) were predictors for duration. The nomogram based on predictive factors exhibited strong discrimination ability, with concordance indices of 0.755 (95% CI = 0.712-0.798) in the training cohort model and 0.717 (95% CI = 0.647-0.787) in the validation cohort model. The calibration curves for the training and validation cohorts showed that the probabilities of the nomogram agreed well with actual probabilities. CONCLUSIONS: Young age, non-extraction and severe crowding (lower arch) can increase the chance of durations of ≤24 months. Rotated teeth, excessive overjet and Bolton ratio (overall) can increase the chance of durations of >24 months.
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Maloclusión , Sobremordida , Humanos , Niño , Adolescente , Adulto Joven , Adulto , Estudios Retrospectivos , Ortodoncia Correctiva , Maloclusión/terapia , Aparatos Ortodóncicos Fijos , Factores SocioeconómicosRESUMEN
OBJECTIVE: To determine the efficacy of acupuncture for hypertension. METHOD: Seven electronic databases were searched on April 13, 2014 to include eligible randomized controlled trials (RCTs). Data were extracted and risk of bias was assessed. Subgroup analyses and meta- analysis were performed. RESULTS: 23 RCTs involving 1788 patients were included. Most trials had an unclear risk of bias regarding allocation concealment, blinding, incomplete outcome data and selective reporting. Compared with sham acupuncture plus medication, a meta-analysis of 2 trials revealed that acupuncture as an adjunct to medication was more effective on systolic (SBP) and diastolic (DBP) blood pressure change magnitude (n=170, SBP: mean difference (MD)= -7.47,95% confidence intervals (CI):-10.43 to -4.51,I2 =0%; DBP: -4.22,-6.26 to -2.18, 0%).A subgroup analysis of 4 trials also showed acupuncture combined with medication was superior to medication on efficacy rate (n=230, odds ratio (OR)=4.19, 95%CI: 1.65 to 10.67, I2 =0%). By contrast, compared with medication, acupuncture alone showed no significant effect on SBP /DBP after intervention and efficacy rate in the subgroup analysis. (7 trials with 510 patients, SBP: MD=-0.56, 95%CI:-3.02 to 1.89,I2 =60%; DBP: -1.01,-2.26 to 0.24, 23%; efficacy rate: 10 trials with 963 patients, OR=1.14, 95% CI: 0.70 to 1.85, I2 =54%).Adverse events were inadequately reported in most RCTs. CONCLUSION: Our review provided evidence of acupuncture as an adjunctive therapy to medication for treating hypertension, while the evidence for acupuncture alone lowing BP is insufficient. The safety of acupuncture is uncertain due to the inadequate reporting of it. However, the current evidence might not be sufficiently robust against methodological flaws and significant heterogeneity of the included RCTs. Larger high-quality trials are required.
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Terapia por Acupuntura/métodos , Antihipertensivos/uso terapéutico , Hipertensión/terapia , Presión Sanguínea/efectos de los fármacos , Terapia Combinada , Humanos , Hipertensión/fisiopatología , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
OBJECTIVE: To evaluate the influence of different surface treatments on porcelain surface topography. METHODS: Metal ceramic prostheses in 6 groups were treated according to the different surface treatment methods, and the surface topography was observed through scanning electron microscope (SEM). Group A was the control one (untreated), group B was etched by 9.6% hydrofluoric acid(HF), group C was deglazed by grinding and then etched by 9.6% HF, group D was treated with Nd: YAG laser irradiation(0.75 W) and HF etching, group E was treated with Nd: YAG laser irradiation (1.05 W) and HF etching, and group F was treated with laser irradiation (1.45 W) and HF etching. RESULTS: Surface topography was different in different groups. A lot of inerratic cracks with the shapes of rhombuses and grid, and crater with a shape of circle were observed on the ceramic surface after treatment with energy parameters of 1.05 W Nd: YAG laser irradiation and 9.6% HF etching (group E). Surface topography showed a lot of concaves on the inner wall of the cracks, and the concaves with diameter of 1-5 microm could be observed on the inner wall of the holes, which had a diameter of 20 microm under SEM. CONCLUSION: The use of Nd: YAG laser irradiation with the energy parameters of 1.05 W and the HF with a concentration of 9.6% can evenly coarsen the porcelain surface, that is an effective surface treatment method.
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Recubrimiento Dental Adhesivo , Porcelana Dental , Cerámica , Ácido Fluorhídrico , Láseres de Estado Sólido , Resistencia al Corte , Propiedades de SuperficieRESUMEN
OBJECTIVE: In order to find out the cause of molar intrusion and how to avoid molar intrusion, we analyze the movement tendency of tooth by changing the angles of upper accentuated-curve and the height of free traction hook. METHODS: Spiral CT scanning and Mimics 10.0 software were employed in this study to construct the three dimensional finite element model of maxillary teeth, periodontal ligaments and alveolar bone as well as the inch stainless steel upper accentuated-curve archwires with different angles (5 degrees, 10 degrees, 15 degrees, 20 degrees, 25 degrees) and the free traction hook with different height (2.1, 4.0, 5.5 mm). By exerting 1.5 N backward force to analysis the displacement trend of maxillary tooth. RESULTS: Upper accentuated-curve archwires made the incisors labially tip, intruse, distally upright and mesilabially torsion; made the canines labially tip, prolong, mesial-tipped and mesi-labially torsion; made the second premolars and the first molars buccal tip, intruse, distal upright and mesi-labially torsion. With the angle of upper accentuated-curve archwires increased, all tooth movement tendency increased; while with the height of free traction hook increased, all tooth movement tendency decreased. CONCLUSION: When the angle of upper accentuated-curve archwires increased, the extent of molar intrusion increased, but when the height of free traction hook increased, the degree of molar intrusion decreased. The degree of molar intrusion was minimum using 5 degrees upper accentuated-curve archwires cooperated with 5.5 mm free traction hook.
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Maxilar , Técnicas de Movimiento Dental , Diente Premolar , Tornillos Óseos , Análisis de Elementos Finitos , Humanos , Incisivo , Diente Molar , Ligamento Periodontal , DienteRESUMEN
OBJECTIVE: To investigate the effects of alcohol intake on penile structure and function in rats. METHODS: Thirty adult male Wistar rats were randomly divided into two groups: control group and alcohol intake group. They were administered with 2 mL of normal saline and 40% alcohol solution respectively through gastric tubes every day. Three months later, the animal model of alcohol intake was evaluated by modified Nayagida's method, and the effects of alcohol on the rats were studied by sexual behavior, the number of apomorphine-induced penile erection, level of testosterone in the sera, and the content of penile smooth muscle. RESULTS: The scores of animal model of alcohol intake evaluated by Nayagida's method were 0.66 +/- 2.05 in the control group and 9.26 +/- 5.50 in the alcohol intake group (P < 0.05), which indicated that an animal model of alcohol intake was successfully established. Sexual behavior, the number of apomorphine-induced penile erection, testosterone level in the sera, and the content of penile smooth muscle of the alcohol intake group were all statistically different as compared with the control group (P < 0.05). CONCLUSION: Alcohol intake induces sexual dysfunction in rats, which may be due to the decline of testosterone level in the sera and decline of penile smooth muscle.