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1.
Inorg Chem ; 62(42): 17241-17253, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37820375

RESUMEN

In order to utilize the synergistic effect between a conductive polymer and an inorganic semiconductor to efficaciously enhance charge transfer and solve the problem of unsatisfactory performance of a single photocatalyst, thiophene (Th) was polymerized on the Cd0.5Zn0.5S nanoparticle surface to prepare a conductive polymer-inorganic polythiophene/Cd0.5Zn0.5S (PTh/CZS) heterostructrue through a simple in situ oxidation polymerization for the first time. The as-prepared PTh/CZS heterostructures significantly improved photocatalytic TCH degradation and hydrogen production activities. Especially, the 15PTh/CZS sample exhibited the optimal hydrogen production rate (18.45 mmol g-1 h-1), which was 2.51 times higher than pure Cd0.5Zn0.5S nanoparticles. In addition, 15PTh/CZS also showed very fast and efficient photodegradation ability for degrading 88% of TCH in 25 min. Moreover, the degradation rate (0.06229 min-1) was five times more than that of Cd0.5Zn0.5S. The π-π* transition characteristics, high optical absorption coefficient, wide absorption wavelength of PTh, the tight contact interface, and synergistic effect of PTh and Cd0.5Zn0.5S efficiently boosted charge transfer rate and increased the light absorption of PTh/CZS photocatalysts, which greatly enhanced the photocatalytic abilities. Besides, the mechanism of improved photocatalytic activities for TCH degradation and H2 production was also carefully proposed. Undoubtedly, this work would provide new insights into coupling conductive polymers to inorganic photocatalysts for achieving multifunctional applications in the field of photocatalysis.

2.
Vaccine ; 41(40): 5825-5833, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37580210

RESUMEN

BACKGROUND: The global burden of disease caused by congenital cytomegalovirus (CMV) infection is high. Previous modeling studies have suggested that CMV vaccination may be cost-effective in developed countries. Congenital CMV infection is more likely driven by maternal non-primary infection in China. We aimed to measure the effectiveness and cost-effectiveness of population-level CMV vaccination in Chinese females. METHODS: A decision tree Markov model was developed to simulate potential CMV vaccination strategies in a multi-cohort setting, with a population size of 1,000,000 each for the infant, adolescent (10-year-old) and young adult (20-year-old) cohorts. The hypothetical vaccines were assumed to have 50% efficacy, 20 years of protection, 70% coverage, at a price of US$120/dose for base-case analysis. Costs and disability-adjusted life years (DALYs) were discounted by 3% per year and the vaccination would be considered cost-effective if an incremental cost-effectiveness ratio (ICER) was lower than 2021 Chinese per capita GDP (US$12,500). FINDINGS: For the pre-infection (PRI) vaccine efficacy type, the adolescent strategy was the most cost-effective, with an ICER of US$12,213 (12,134 to 12,291) pre DALY averted, compared with the next best strategy (young adult strategy). For pre- and post-infection (P&PI) efficacy type, the young adult strategy was the most cost-effective as it was cost-saving. In one-way analysis varying the PRI vaccine price, the infant strategy, adolescent strategy and the young adult strategy would be a dominant strategy over others if the vaccine cost ≤US$60, US$61-121 and US$122-251 per dose respectively. In contrast, the young adult strategy continued to be the preferred strategy until the P&PI vaccine price exceeded US$226/dose. Our main results were robust under a wide variety of sensitivity analyses and scenario analyses. INTERPRETATION: CMV vaccination for females would be cost-effective and even cost-saving in China. Our findings had public health implications for control of CMV diseases.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Lactante , Femenino , Adolescente , Adulto Joven , Humanos , Niño , Adulto , Análisis Costo-Beneficio , Vacunación/métodos , Infecciones por Citomegalovirus/prevención & control , China
3.
Shanghai Kou Qiang Yi Xue ; 32(1): 101-104, 2023 Feb.
Artículo en Chino | MEDLINE | ID: mdl-36973853

RESUMEN

PURPOSE: To investigate the difference of osteogenic effect and stability of maxillary sinus implants 6 months after maxillary sinus elevation with or without bone grafting. METHODS: A total of 150 patients with maxillary sinus floor lift and simultaneous implantation in Lishui People's Hospital from December 2019 to December 2021 were divided into group A (internal maxillary sinus lift + bone grafting) and group B (internal lift without bone grafting). Preoperative and postoperative CBCT data and implant stability of all patients were measured and analyzed to compare whether there were differences in clinical efficacy between the two groups. SPSS 25.0 software package was used for data analysis. RESULTS: A total of 199 implants were implanted, the implant retention rate was 97.6% in group A and 95.7% in group B one year after surgery, with no significant difference between the two groups(P>0.05). There was no significant difference in residual bone height(RBH) and gray scale value (HU) between the two groups before and 6 months after operation (P>0.05). There was no significant difference in ISQ value between the two groups during operation and 6 months after operation(P>0.05). CONCLUSIONS: In cases with the remaining alveolar bone height of 3~8 mm and the planned lifting height of 3~4 mm, maxillary sinus floor lifting procedure achieved good clinical results in both groups with or without bone grafting, which indicated that bone grafting had little effect on retention rate and stability of the implants.


Asunto(s)
Implantes Dentales , Elevación del Piso del Seno Maxilar , Humanos , Implantación Dental Endoósea/métodos , Trasplante Óseo , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Resultado del Tratamiento , Maxilar/diagnóstico por imagen , Maxilar/cirugía
4.
Inorg Chem ; 61(48): 19552-19566, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36409305

RESUMEN

Light-driven splitting of water to produce H2 and reduction of molecular oxygen to synthesize H2O2 from water are the emerging environmentally friendly methods for converting solar energy into green energy and chemicals. In this paper, vacancy defect and heterojunction engineering effectively adjusted the conduction band position of Zn3In2S6, enriched the electron density, broadened the optical absorption range, increased the specific surface area, and accelerated the charge carrier transfer and separation of g-C3N4/sulfur-vacancy-containing Zn3In2S6 (CN/Vs-ZIS) heterostructures. As a result, all of the CN/Vs-ZIS heterostructures possessed greatly enhanced photocatalytic activities and the optimized sample 2CN/Vs-ZIS exhibited the highest visible-light photocatalytic performance. The rate of generation of H2 of 2CN/Vs-ZIS under visible light (λ > 420 nm) was 6.55 mmol g-1 h-1, which was 1.76 and 6.06 times higher than those of Vs-Zn3In2S6 and g-C3N4, respectively, and the apparent quantum yield (AQY) was 18.6% at 420 nm. Meanwhile, the 2 h yield of H2O2 of 2CN/Vs-ZIS was 792.02 µM, ∼4.72 and ∼6.04 times higher than those of pure Vs-Zn3In2S6 and g-C3N4, respectively. The enhanced reaction mechanisms for the production of photocatalytic H2 and H2O2 were also investigated. This work undoubtedly demonstrates that the synergistic effects of defect and heterojunction engineering will be the great promise for improving the photocatalytic efficiency of Zn3In2S6-based materials.

5.
J Dent Sci ; 17(3): 1151-1159, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35784115

RESUMEN

Background/purpose: Clinical esthetic evidence for the performance of monolithic high-translucency multilayer zirconia is lacking. The aim of this study was to compare monolithic high-translucency multilayer zirconia with traditional veneered zirconia in clinical situation. Material and methods: A total of 30 participants who were provided with both monolithic zirconia crowns (Group 1) and traditional veneered crowns (Group 2) for single implant restoration in maxillary esthetic areas were enrolled. Patients' subjective outcome (Visual Analog Scale, VAS) were recorded. Photos were taken and then evaluated by 9 evaluators with Pink and White Esthetic Score (WES). Wilcoxon signed rank test was used for comparison between Group 1 and Group 2 in VAS, WES and five variables in WES. Kendall's coefficient of concordance test was used to calculate inter-rater reliability of WES variables. Spearman correlation was used to analyze association between patients' outcome and evaluators' scores. Results: There was no significant difference in patients' subjective outcome between monolithic zirconia and traditional veneered crowns: overall VAS were 9.0 (8.0-9.0) and 9.0 (8.5-9.5), respectively (P > 0.05). However, in professional view, significant difference between Group 1 and Group 2 in WES was observed: 7.5 (6.0-8.0) and 8.0 (6.5-8.5), respectively (P < 0.05). Kendall's test showed, among WES variables, translucency demonstrated the highest agreement. Professionally reported evaluations did not correlate with patient-reported outcomes (Spearman correlation were 0.246 and 0.224 for Group 1 and Group 2, respectively). Conclusion: Within the limitation of this study, it can be concluded that monolithic high-translucency multilayer zirconia restoration might be a treatment modality.

6.
Mater Horiz ; 9(7): 1978-1983, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35603715

RESUMEN

Piezocatalysis, the process of directly converting mechanical energy into chemical energy, has emerged as a promising alternative strategy for green H2 production. Nevertheless, conventional inorganic piezoelectric materials suffer from limited structural tailorability and small surface area, which greatly impedes their mechanically driven catalytic efficiency. Herein, we design and fabricate a novel UiO-66(Zr)-F4 metal-organic framework (MOF) nanosheet for piezocatalytic water splitting, with the highest H2 evolution rate reaching 178.5 µmol g-1 within 5 h under ultrasonic vibration excitation (110 W, 40 kHz), far exceeding that of the original UiO-66 host. A reduced bandgap from 2.78 to 2.43 eV is achieved after introducing a fluorinated ligand. Piezoresponse force microscopy measurements demonstrate a much stronger piezoelectric response for UiO-66(Zr)-F4, which may result from the polarity of the introduced fluorinated ligand. This work highlights the potential of MOF-based porous piezoelectric nanomaterials in harvesting mechanical energy to drive chemical reactions such as water splitting.

7.
Shanghai Kou Qiang Yi Xue ; 31(1): 38-43, 2022 Feb.
Artículo en Chino | MEDLINE | ID: mdl-35587666

RESUMEN

PRUPOSE: To investigate the effect of a compound of BMSCs-Bio-Oss-bFGF on microstructure of extraction sockets in rats. METHODS: Bone mesenchymal stem cells (BMSCs) were isolated from bone marrow of 3-week SD rats by adherent method. Maxillary posterior teeth of 36 6-week SD rats were extracted and materials were implanted into sockets according to grouping. The rats were divided into 4 groups: compound group with implanting BMSCs-Bio-Oss-bFGF compound, powder group with implanting Bio-Oss, BMSCs group with implanting BMSCs, and control group without implanting any materials. The sockets were scanned by micro-CT 4 weeks, 12 weeks and 24 weeks after implantation. Two-way ANOVA was used to assess whether there was significant difference between groups with GraphPad Prism 6.0 software package. RESULTS: There was no significant difference among groups in bone mineral density (BMD), trabecular separation(Tb.Sp), trabecular thickness(Tb.Th), degree of anisotropy(DA), and trabecular number(Tb.N) 4 weeks after implantation. By 12 weeks, BMD of compound group was significantly greater than those of BMSCs group, powder group and control group (P<0.05), and significantly greater than those of powder group and control group at 24 weeks (P<0.05). Tb.Th of compound group was significantly greater than that of BMSCs group at 12 and 24 weeks(P<0.05). DA had no significant difference among groups at 4, 12, and 24 weeks (P>0.05). Tb.Sp of compound group was significantly smaller than those of powder group, BMSCs group and control group at 24 weeks(P<0.05). Tb.N of compound group was significantly greater than those of BMSCs group and control group(P<0.05). CONCLUSIONS: The compound of rat allogeneic BMSCs-Bio-Oss-bFGF improves socket healing.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Células Madre Mesenquimatosas , Animales , Factor 2 de Crecimiento de Fibroblastos , Minerales , Polvos , Ratas , Ratas Sprague-Dawley , Extracción Dental , Alveolo Dental , Microtomografía por Rayos X
8.
J Colloid Interface Sci ; 623: 109-123, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35569220

RESUMEN

In this work, a novel hierarchical 1D/2D core/shell Sb2S3-ZnIn2S4 (SB-ZIS) heterostructure with highly efficient photocatalytic activities for both hydrogen production from water and organic pollutant degradation was designed and fabricated via a simple one-step hydrothermal method. The as-prepared SB-ZIS heterostructure, where ZnIn2S4 nanosheets uniformly grew onto Sb2S3 nanorod to form a tight and large intimate contacted interface, was conducive to improve the absorption capacity of light, increase the surface area, shorten the distance of electronic transmission channels and accelerate the separation and migration of photogenerated carriers. As a result, the presented SB-ZIS composites demonstrated significantly enhanced photocatalytic performances for H2 generation and Tetracycline Hydrochloride (TCH) photodegradation. The photocatalytic H2 production rate of optimal SB-ZIS-2 sample (1685.14 µmol·g-1·h-1) was about 12.24 times as large as that of pure ZnIn2S4 (137.63 µmol·g-1·h-1). The apparent quantum efficiency (AQE) at 420 nm was up to 3.8%. In addition, the highest rate constant for TCH removal (0.514 h-1) was 20.3 and 2.89 times larger than those of pure Sb2S3 and Znln2S4, respectively. The possible reaction routes of TCH and the photocatalytic reaction mechanism of SB-ZIS sample were also discussed in detail. This work will provide some useful information for the development of dual-functional Sb2S3-based type I core-shell heterostructure with an efficient photocatalytic activity for solving environmental pollution and producing clean hydrogen energy.


Asunto(s)
Contaminantes Ambientales , Nanotubos , Hidrógeno/química , Fotólisis , Tetraciclina/química
9.
Environ Res ; 209: 112800, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35085566

RESUMEN

In recent years, carbon quantum dots (CQDs) and CdIn2S4 have considered as the representatives of the most potential photocatalysts applied in the field of photocatalysis for efficiently solving energy shortage and environmental pollution. In this work, a novel CQDs hybridized CdIn2S4 (CQDs/CIS) heterostructure with 2D nanosheet/3D nanooctahedra morphology was successfully fabricated by a simple in-situ solvothermal method. Most interestingly, the morphology of hybrid gradually evolved from 3D octahedron to 2D nanosheet with the increase of CQDs. This unique 2D/3D structure and synergistic effect between CQDs and CdIn2S4 increased the multi-dimensional active reaction sites and enhanced the quantum yield and the separation efficiency of photogenerated electron pairs. Therefore, CQDs/CIS hybrids showed excellent photocatalytic activities of H2 generation, RhB and TCH degradation. Especially, CQDs/CIS-3 heterostructure presented the highest photocatalytic efficiency and its hydrogen generation activity (956.79 µmol g-1 h-1) was 7.57-fold improvement by contrast with pure CdIn2S4 (126.35 µmol g-1 h-1). Moreover, RhB and TCH degradation rate constants of CQDs/CIS-3 were about 8.14 and 2.32 times higher than those of CdIn2S4, respectively. Furthermore, the effect of CQDs on the evolution of heterostructure morphology and photocatalytic mechanism were also proposed. This research work would offer useful enlightenment for elucidating the affect of CQDs on the morphology evolution and construction of CQDs-based hybrid with excellent performances for H2 production and pollutant removal.


Asunto(s)
Contaminantes Ambientales , Puntos Cuánticos , Carbono , Catálisis , Hidrógeno , Puntos Cuánticos/química
10.
Shanghai Kou Qiang Yi Xue ; 30(5): 551-555, 2021 Oct.
Artículo en Chino | MEDLINE | ID: mdl-34888613

RESUMEN

PURPOSE: To perceive the dental undergraduate's policy of coping with online learning and their decision-making laws during the COVID-19 pandemic. METHODS: For dental undergraduate students from the 2016 grade to 2018 grade of Lishui University, two prospective questionnaire surveys were conducted before the online course starting and four weeks later. SPSS Modeler18.0 software was used to screen, review, and analyze the data. TAN (tree augmented naive) Bayesian network models were utilized to analyze and predict variables. Indicators like the overall prediction accuracy, receiver operating characteristic curve (ROC curve), and area under the ROC curve(AUC value) were applied to evaluate the model's predicting performances. RESULTS: The case score of each survey was 422 and 382, and the Cronbach's α coefficients of internal consistency were 0.91 and 0.82. Among the decision-making variables in the aspect of "whether to preview online learning materials", the top-two variables were "looking forward to the semester beginning" and "the validity of the network materials". In speaking of "whether the online courses meet the offline course standards", the top-three variables were "the rhythm of lecturing on live or in recorded videos", "how many online tasks', and" the data frame and organization". The overall prediction accuracy of each constructed TAN Bayesian network model was 89.42% and 87.82%, and their AUC values were 0.75 and 0.93, respectively. CONCLUSIONS: To truly make online courses comparable to the off-line curriculum, teachers should fully understand how the students cope with their online learning at first. Then, only by perceiving and recognizing the students' expectations for education, by efficiently preparing and organizing online materials with all-round, clearly-structured, vivid, comprehensible contents and moderate difficult tasks, by well interacting with students through different websites and social media, can we truly achieve " ongoing learning with suspended class".


Asunto(s)
COVID-19 , Educación a Distancia , Humanos , Teorema de Bayes , Toma de Decisiones , Pandemias , Estudios Prospectivos , SARS-CoV-2 , Estudiantes
11.
JAMA Netw Open ; 4(9): e2125544, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34533568

RESUMEN

Importance: Early identification and intervention for newborns with hearing loss (HL) may lead to improved physiological and social-emotional outcomes. The current newborn hearing screening is generally beneficial but improvements can be made. Objective: To assess feasibility and evaluate utility of a modified genetic and hearing screening program for newborn infants. Design, Setting, and Participants: This population-based cohort study used a 4-stage genetic and hearing screening program at 6 local hospitals in Nantong city, China. Participants were newborn infants born between January 2016 and June 2020 from the Han population. Statistical analysis was performed from April 1 to May 1, 2021. Exposures: Limited genetic screening for 15 variants in 4 common HL-associated genes and newborn hearing screening (NHS) were offered concurrently to all newborns. Hearing rescreening and/or diagnostic tests were provided for infants with evidence of HL on NHS or genetic variants on screening. Expanded genetic tests for a broader range of genes were targeted to infants with HL with negative results of limited genetic tests. Main Outcomes and Measures: The detection capability for infants with hearing impairment who passed conventional hearing screening, as well as infants with normal hearing at risk of late-onset HL due to genetic susceptibility. Results: Among a total of 35 930 infants, 32 512 infants completed the follow-up and were included for analysis. Among the infants included in the analysis, all were from the Han population in China and 52.3% (16 988) were male. The modified genetic and hearing screening program revealed 142 cases of HL and 1299 cases of genetic variation. The limited genetic screening helped identify 31 infants who passed newborn hearing screening, reducing time for diagnosis and intervention; 425 infants with normal hearing with pathogenic SLC26A4 variation and 92 infants with MT-RNR1 variation were at risk for enlarged vestibular aqueduct and aminoglycoside-induced ototoxicity respectively, indicating early aversive or preventive management. Conclusions and Relevance: This study found that performing modified genetic and hearing screening in newborns was feasible and provides evidence that the program could identify additional subgroups of infants who need early intervention. These findings suggest an advantage for universal adoption of such a practice.


Asunto(s)
Pruebas Genéticas , Pérdida Auditiva/diagnóstico , Pruebas Auditivas , Tamizaje Neonatal/métodos , China , Diagnóstico Precoz , Estudios de Factibilidad , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Genotipo , Pérdida Auditiva/genética , Humanos , Recién Nacido , Masculino , Fenotipo , Proyectos Piloto , Factores de Riesgo
12.
J Dent Sci ; 16(3): 948-956, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34141109

RESUMEN

BACKGROUND/PURPOSE: Information regarding agreements between periapical radiograph (PA) and cone beam computed tomography (CBCT) in detecting peri-implant defect is still scarce. The aim of this clinical study was to compare agreements between PA and CBCT in detecting peri-implant bone defect. MATERIALS AND METHODS: This retrospective clinical study enrolled 32 patients with both PA and CBCT filmed right after implant placement. Four modalities were used for film reading: PA1 (original), PA2 (enhanced brightness/contrast), CBCT1 (selected axial and mesial-distal direction images) and CBCT2 (all data with software). 2 experienced and 2 inexperienced observers scored all films. Intra- and inter-observer agreements were estimated with Cohen's kappa coefficient. Categorized agreements were compared and differences among four modalities were calculated. RESULTS: Agreements of PA were better than CBCT when detecting peri-implant bone defects in inter-observer agreements (median kappa 0.471 vs. 0.192; p = 0.016). Moreover, agreements in experienced observers were better than inexperienced observers (median kappa 0.883 vs. 0.567; p < 0.001). There was significant difference among four modalities except for experienced observer 2 (p = 0.218). CONCLUSION: Agreements of PA are better than CBCT when detecting peri-implant bone defects, especially for inter-observer agreements. Experienced observers are more consistent in assessment than inexperienced ones.

13.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(5): 558-565, 2020 Oct 01.
Artículo en Chino | MEDLINE | ID: mdl-33085242

RESUMEN

OBJECTIVE: This study aims to investigate the expression of fibroblast growth factor receptor like 1 (FGFRL1) in oral squamous cell carcinoma (OSCC) and reveals its association with tumor cell proliferation and migration. METHODS: Western blot was performed to detect the expression of FGFRL1 protein in OSCC tissues, adjacent normal tissues, OSCC cell lines and normal epithelial cells. After knocking down of FGFRL1 in HN4 cells, CCK-8 and Ki67 assays were performed to detect cell proliferation, wounding healing assay and transwell were performed to detect cell-migration. Western blot was used to detect the expression of protein related to epithelial-mesenchymal transition (EMT). RESULTS: The expression of FGFRL1 in OSCC tissues was higher than that in adjacent nontumor tissues, respectively (t=2.820, P=0.047 8). Moreover, the expression of FGFRL1 in OSCC cells was higher than that in HOK cells. Quantitative real-time polymerase chain reaction (qRT-PCR) showed that FGFRL1 expression of FGFRL1 RNA in HOK cells was lower than that in OSCC cells. HN4 cells transfected with FGFRL1 siRNA were included in the experimental group, whereas HN4 cells treated with NC siRNA were included in the control group. CCK-8 experiment showed no significant difference between the experimental and control groups with regard to proliferation ability at 48 h (P=0.478 1) and 72 h (P=0.334 2). Migration experiment showed that the wound healing areas in the experimental group after 12 h (P=0.022 8), 24 h (P=0.005 1), and 36 h (P=0.009 5)were smaller than that in the control group. Transwell invasion assay showed that the number of invaded cells in the experimental group after 16 h (P=0.008 7) and 24 h (P=0.008 6) were lower than that in the control group. Knocking-down FGFRL1 up-regulated the expression of E-cadherin and down-regulated the expression of N-cadherin and Vimentin in HN4 cells. CONCLUSIONS: FGFRL1 expression in the OSCC tissues was significantly higher than that in the adjacent nontumor tissues. FGFRL1 expression in the OSCC cells was significantly higher than that in the HOK cells, and FGFRL1 had no effect on cell proliferation but promoted tumor cell migration and EMT.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Boca , Línea Celular Tumoral , Proliferación Celular , Humanos , Receptor Tipo 5 de Factor de Crecimiento de Fibroblastos/fisiología , Receptores de Factores de Crecimiento de Fibroblastos
14.
J Colloid Interface Sci ; 576: 505-513, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32512403

RESUMEN

The electrolyte additives of potassium ferricyanide and potassium persulfate can ensure that CoO-supercapacitors achieve a fast charge/slow discharge and long cycling stability. The redox couple of Fe(CN)63-/Fe(CN)64- can induce S2O82- to produce the sulfate radical ( [Formula: see text] ). Strong oxidizing species, including S2O82-, Fe(CN)63- and [Formula: see text] , can accelerate oxidation of the CoO electrode surface from Co2+ to Co3+ in the charge process. The additives can achieve a good synergistic effect on accelerating CoO oxidation during the charge process. In a three-electrode cell, a CoO electrode with electrolyte additives achieves a fast-charge and slow-discharge time of 939 s and 1699 s at a current density of 1 A g-1, respectively. The capacitance retention can be maintained at 84.5% after 10,000 cycles at a current density of 5 A g-1. As a supercapacitor, the device can achieve a fast-charge and slow-discharge time of 156 s and 191 s at a current density of 1 A g-1, respectively. The capacitance retention can be maintained at 85.5% after 10,000 cycles at a current density of 5 A g-1.

15.
Shanghai Kou Qiang Yi Xue ; 29(1): 55-59, 2020 Feb.
Artículo en Chino | MEDLINE | ID: mdl-32524122

RESUMEN

PURPOSE: To observe the effect of bone grafting during the extraction of mandibular third molar on repair of distal alveolar bone defect distal to the second molar. METHODS: The risks of the distal alveolar bone defect in the second molar were estimated after removal of the impacted teeth according to the position of the third molar and second molar before operation. It was divided into three groups: low risk group, medium risk group and high risk group. The medium risk group and high risk group were further divided into bone graft subgroup (group A) and non-bone graft subgroup (group B). There were 36 cases in group A and 45 cases in group B. Postoperative re-examination indicators included subjective perception of the patients, depth of probing and height of alveolar bone in the distal molar of the second molar by X-ray examination. The data were analyzed with SPSS 19.0 software package. RESULTS: Six months after operation, in mediun risk group, 0 cases in group A had subjective feelings of cold and heat stimulation; in group B, the number was 6 cases, the difference was significant (P<0.05). Distal periodontal probing depth of the second molar was (2.93±0.34) mm in group A and (2.95±0.50) mm in group B. There was no significant difference between 2 groups (P=0.931). X-ray examination of the alveolar bone height increment of the second molar Δh: (3.31±1.02) mm in group A, (3.10±1.72) mm in group B, the difference was not significant (P=0.794). In high risk group, 4 cases in group A had subjective feelings of cold and heat stimulation; in group B, the number was 10 cases,the difference was significant (P<0.05). Distal periodontal probing depth of the second molar was (3.08±0.37) mm in group A and (3.24±0.41) mm in group B. There was no significant difference between 2 groups(P=0.931). X-ray examination of the alveolar bone height increment of the second molar Δh: (5.21±1.79) mm in group A, (2.99±2.42) mm in group B, the difference was significant (P<0.05). CONCLUSIONS: Risk classification of the second molar distal bone defects after extraction of the impacted teeth is essential, which is helpful to determine whether bone grafting is needed during operation. Autologous bone mixed with Bio-Oss artificial bone powder can promote recovery of the alveolar bone height of the second molar, especially in high risk group, and discomfort caused by exposure can be reduced.


Asunto(s)
Diente Impactado , Trasplante Óseo , Humanos , Mandíbula , Diente Molar , Tercer Molar , Extracción Dental
16.
J Colloid Interface Sci ; 575: 168-176, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32361233

RESUMEN

The rational design and simple synthesis of high performance electrodes are important aspects of energy storage fields. However, it is difficult to determine a facile preparation method to obtain hierarchical Ni3S2 nanorod/sheet arrays. Herein, hydrogen peroxide-induced growth by the hydrothermal method is used to fabricate the hierarchical Ni3S2 nanorod/sheet arrays on nickel foam substrates. Hydrogen peroxide can accelerate the hydrolysis of Na2S2O3 to release sulfur ions and then induce formation of the hierarchical nanorod/sheet. The one-dimensional nanorod skeleton acting as high-speed electron transfer channels can support the nanosheets. The two-dimensional nanosheets can provide abundant active edge sites and protect the backbone from electrochemical corrosion. The hierarchical structure integrates the advantages of sufficient active sites, effective protection and high-speed electron transfer. The electrode based on the Ni3S2 nanorod/sheet delivers a high specific capacitance of 6.87 F cm-2 at 2 mV s-1 (6.24 F cm-2 at 5 mA cm-2) and long cycling stability (85.7% capacitance retention at 15 mA cm-2 after 3000 cycles). The asymmetric supercapacitor gains a high energy density of 1.16 mWh cm-3 at 15.00 W cm-3. The hierarchical Ni3S2 nanorod/sheet arrays are expected to be candidates for the electrodes of practical supercapacitors.

17.
Sci Rep ; 10(1): 4735, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32170188

RESUMEN

Surveying the quality and quantity of carbon stock in litter layer and woody debris of Eucalyptus and Acacia plantations is critical in understanding their carbon pools. Here, the focus of the present study was on a number of Eucalyptus and Acacia plantations of different stand aged in the Pearl River Delta region of southern China. The plantation type proved to be a crucial driver of the carbon concentration in litter layer and woody debris, with Acacia exhibiting a superior ability to Eucalyptus to accumulate carbon with stand age in both these materials. The relative contribution of the litter layer and woody debris to the carbon stock of the ecosystem was also significantly higher under mature Acacia (8% and 7%, respectively) than that under mature Eucalyptus (4% and 1%, respectively). Most of the carbon stock within the litter layer was present in the leaf debris. The carbon stock in woody debris was mainly contained in the components within the 10-20 cm diameter class during the primary decay stage, represented as snags in middle-aged and mature Acacia, and as logs for mature Eucalyptus, respectively. The results indicate that both plantation type and stand age influence the characteristics of carbon stored in litter layer and woody debris significantly.


Asunto(s)
Acacia/metabolismo , Biomasa , Carbono/análisis , Ecosistema , Eucalyptus/metabolismo , Carbono/metabolismo , China , Agricultura Forestal , Suelo/química
18.
Appl Spectrosc ; 73(11): 1284-1291, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31219335

RESUMEN

Toxic metals in medicinal herbs are potentially harmful for people taking herbal medicines. In this work, laser-induced breakdown spectroscopy-laser-induced fluorescence (LIBS-LIF) spectroscopy was first applied to carry out rapid and sensitive trace lead analysis in medicinal herb samples. To overcome the problem of diversity on the sample size, shape, and density for different samples, original samples were pulverized to powder and then pressed into pellets for spectral analysis. A series of standard samples were self-made for building a calibration curve. As an exemplary study, lead in Rheum officinale was analyzed with LIBS-LIF spectroscopy with significantly improved analytical sensitivity. The R2 of the build linear calibration curve was 0.996 and the detection limit of lead in R. officinale was determined to be 0.13 ppm. The enhancement factor on the signal-to-background ratio was >100 under low lead concentrations if compared with LIBS analysis. The lead concentrations in several original R. officinale samples were quantitatively determined. This work demonstrated that LIBS-LIF can be successfully applied to carry out rapid, sensitive, and quantitative trace lead analysis for medicinal herbs.


Asunto(s)
Plomo/análisis , Plantas Medicinales/química , Espectrometría de Fluorescencia/métodos , Rayos Láser , Límite de Detección , Modelos Lineales
19.
Shanghai Kou Qiang Yi Xue ; 27(4): 440-444, 2018 Aug.
Artículo en Chino | MEDLINE | ID: mdl-30483719

RESUMEN

With the degree of enrollment of postgraduates in medical specialty expanding year by year, medical colleges have been exposed the deficiencies in the education of professional degree, which is paying more attention to clinic but less to scientific research. Postgraduate students have weak scientific awareness and less enthusiasm. This study forward on reforming the teaching model and incentive strategy based on the questionnaire survey. The purpose was to encourage the professional degree postgraduate students to be involved in scientific research initiative, innovation ability, and improve the quality of postgraduate education.


Asunto(s)
Educación en Odontología , Motivación , Universidades , Selección de Profesión , Estudiantes , Encuestas y Cuestionarios
20.
Shanghai Kou Qiang Yi Xue ; 27(3): 302-304, 2018 Jun.
Artículo en Chino | MEDLINE | ID: mdl-30411129

RESUMEN

PURPOSE: To evaluate the influence of pretreatment radiographic features (angle, distance, and location) on the duration of active orthodontic traction. METHODS: Sixty maxillary unilateral impacted canines were selected to analyze the panoramic features(angle, line spacing, and location) in pre-treatment patients, the results were evaluated using SPSS19.0 software package for multivariate regression analysis. RESULTS: Pretreatment radiographic variables (angle, line spacing, and location) were significantly associated with the duration of orthodontic traction. The sex and site of impaction did not significantly affect the duration of traction. CONCLUSIONS: Impacted canine angle, distance and position can predict the orthodontic traction time.


Asunto(s)
Maxilar , Radiografía Panorámica , Diente Impactado , Diente Canino , Humanos , Maxilar/diagnóstico por imagen , Diente Impactado/diagnóstico por imagen
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