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1.
Nat Mater ; 23(3): 383-390, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38062169

RESUMEN

Transparent conducting oxides are a critical component in modern (opto)electronic devices and solar energy conversion systems, and forming textured functional films on them is highly desirable for property manipulation and performance optimization. However, technologically important materials show varied crystal structures, making it difficult to establish coherent interfaces and consequently the oriented growth of these materials on transparent conducting oxides. Here, taking lattice-mismatched hexagonal α-Fe2O3 and tetragonal fluorine-doped tin oxide as the example, atomic-level investigations reveal that a coherent ordered structure forms at their interface, and via an oxygen-mediated dimensional and chemical-matching manner, that is, matched Voronoi cells of oxygen sublattices, [110]-oriented α-Fe2O3 films develop on fluorine-doped tin oxide. Further measurements of charge transport characteristics and photoelectronic effects highlight the importance and advantages of coherent interfaces and well-defined orientation in textured α-Fe2O3 films. Textured growth of lattice-mismatched oxides, including spinel Co3O4, fluorite CeO2, perovskite BiFeO3 and even halide perovskite Cs2AgBiBr6, on fluorine-doped tin oxide is also achieved, offering new opportunities to develop high-performance transparent-conducting-oxide-supported devices.

2.
Angew Chem Int Ed Engl ; : e202409876, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38923765

RESUMEN

Lattice-oxygen activation has emerged as a popular strategy for optimizing the performance and selectivity of oxide-based thermocatalysis and electrolysis. However, the significance of lattice oxygen in oxide photocatalysts has been ignored, particularly in gas‒solid reactions. Here, using methane oxidation over a Ru1@ZnO single-atom photocatalyst as the prototypical reaction and via 18O isotope labelling techniques, we found that lattice oxygen can directly participate in gas‒solid reactions. Lattice oxygen played a dominant role in the photocatalytic reaction, as determined by estimating the kinetic constants in the initial stage. Furthermore, we discovered that dynamic diffusion between O2 and lattice oxygen proceeded even in the absence of targeted reactants. Finally, single-atom Ru can facilitate the activation of adsorbed O2 and the subsequent regeneration of consumed lattice oxygen, thus ensuring high catalyst activity and stability. The results provide guidance for next-generation oxide photocatalysts with improved activities and selectivities.

3.
J Oral Rehabil ; 50(5): 351-359, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36704914

RESUMEN

BACKGROUND: Mouth breathing (MB) can affect morphological changes in the craniofacial structures, electromyography is widely used for quantitative analysis of muscle function. OBJECTIVE: The aim was to evaluate the electromyographic (EMG) activities of the anterior temporalis (TA), masseter muscle (MM), orbicularis oris superior (OOS) and mentalis muscle (MT) in children with different vertical skeletal patterns and breathing modes during rest and various functional mandibular movements. METHODS: BioEMG III was used to measure the variations in EMG activities of TA, MM, OOS, and MT in 185 subjects aged 6-12 years during continuous clenching, rest, maximal intercuspation, lips closed lightly and swallowing. RESULTS: The results of logistic regression analysis showed that the model with vertical skeletal patterns as the dependent variable was ineffective (p = .106), while the model with breathing modes as the dependent variable was effective (p = .000). When considering both vertical skeletal patterns and breathing modes, the following significant differences were found. (1) In the normal-angle group, the EMG ratio in OOS with lips closed lightly of MB was significantly higher than NB (p = .005). (2) In the low-angle group, EMG ratios in TA and MM during the swallowing of MB were significantly lower than NB (p = .020, p = .040, respectively). (3) In the high-angle group, EMG ratios of MB were significantly higher in MT during continuous clenching, rest, lips closed lightly and swallowing (p = .038, p = .036, p = .005, p = .028, respectively), and OOS with lips closed lightly compared to NB (p = .005). CONCLUSION: Breathing modes and vertical skeletal patterns interacted to alter maxillofacial EMG activities, with breathing modes having a greater effect.


Asunto(s)
Músculos Faciales , Labio , Niño , Humanos , Músculos Faciales/fisiología , Labio/fisiología , Músculo Masetero/fisiología , Mandíbula , Músculo Temporal/fisiología , Electromiografía/métodos , Respiración por la Boca
4.
BMC Pediatr ; 22(1): 506, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-36008795

RESUMEN

OBJECTIVES: This study aimed to examine the clinical effects of myofunctional treatment on children with functional mouth breathing by cephalometric radiographs and study models. METHODS: A total of 224 children (6-10 years old; 114 males and 110 females; SNA°: 82.24 ± 1.67°; ANB°: 2.79 ± 0.80°, 28° < SN-GoGn° < 37°) formed three groups: MB-M group (mouth breathers with myofunctional treatment,n = 75); MB-N group (mouth breathers with no treatment,n = 70); NB group (nasal breathers with no treatment, n = 79). A blind evaluation of cephalometric radiographs and study models was conducted at T1(pre-study) and T2 (post-study), respectively. RESULTS: Two hundred four children (MB-M:66, MB-N:68, NB:70) completed the present study. At T1, MB-M and MB-N groups, compared to their NB counterpart, had greater anterior lower facial height(P < 0.01) and overjet(P < 0.001) but shorter overbite and maxillary canines width (P < 0.001). At T2, the MB-N group exhibited a higher ANB angle, anterior lower facial height, and overjet, but shorter overbite and maxillary canines width (P < 0.001). From T1 to T2, the anterior lower facial height increased, overbite and the maxillary canines width further decreased in the MB-N group (P < 0.001). However, in the MB-M group, the incisors were retracted, overbite increased (P < 0.001), anterior lower facial height increased insignificantly (P > 0.05), and maxillary canines width increased slightly (P < 0.05). In the NB and MB-M groups, the mandible showed a normal tendency to grow forward, whereas, in the MB-N group, the mandible showed a tendency to grow downward (P < 0.001). CONCLUSIONS: Mouth breathers demonstrated increased anterior facial height and overjet but reduced overbite and maxillary arch width, which improved significantly following myofunctional treatment. TRIAL REGISTRATION: TCTR: TCTR20220401001 . Registered 1stApril 2022-Retrospectively registered.


Asunto(s)
Respiración por la Boca , Sobremordida , Cefalometría , Dentición Mixta , Femenino , Humanos , Masculino , Mandíbula , Respiración por la Boca/terapia
5.
BMC Oral Health ; 22(1): 228, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35681197

RESUMEN

BACKGROUND: This retrospective study investigated the effect of breathing pattern, skeletal class (Class I, Class II), and age on the hyoid bone position (HBP) in normodivergent subjects. METHODS: A total of 126 subjects (61 males, 65 females) aged 7-9 years and 10-12 years were scanned using cone-beam computed tomography (CBCT). All participants were classified according to the anteroposterior skeletal pattern into (Class I, Class II). Each skeletal group was further divided according to the breathing mode into mouth breathers (MB) and nasal breathers (NB). The HBP was measured accordingly. Independent sample t-test and Mann Whitney U test were used to detect significant differences between the groups, and binary logistic regression was used to identify MB predictive indicators. RESULTS: The breathing mode and skeletal class affected the vertical HBP in subjects with 7-9 years, while they affected the anteroposterior HBP in subjects with 10-12 years. Regarding the age effect, hyoid bone was located more anteriorly in the older NB subjects, and hyoid bone was more inferiorly in the older age group. A regression equation of the significant variables was formulated, C3-Me (P: 001, OR: 2.27), and H-EB (P: 0.046, OR: 1.16) were positively correlated with occurrence of MB. CONCLUSION: There were significantly different HBPs among subjects with different anteroposterior skeletal classes, breathing modes, and age cohorts. Moreover, C3-Me, and H-EB were significant predictors and correlated with increased likelihood of being MB subject.


Asunto(s)
Hueso Hioides , Respiración por la Boca , Anciano , Cefalometría/métodos , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Hueso Hioides/diagnóstico por imagen , Masculino , Mandíbula , Respiración por la Boca/diagnóstico por imagen , Estudios Retrospectivos
6.
BMC Oral Health ; 22(1): 320, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35915494

RESUMEN

OBJECTIVE: This study aimed to investigate whether the subjects with mouth breathing (MB) or nasal breathing (NB) with different sagittal skeletal patterns showed different maxillary arch and pharyngeal airway characteristics. METHODS: Cone-beam computed tomography scans from 70 children aged 10 to 12 years with sagittal skeletal Classes I and II were used to measure the pharyngeal airway, maxillary width, palatal area, and height. The independent t-test and the Mann-Whitney U test were used for the intragroup analysis of pharyngeal airway and maxillary arch parameters. RESULTS: In the Skeletal Class I group, nasopharyngeal airway volume (P < 0.01), oropharyngeal airway volume (OPV), and total pharyngeal airway volume (TPV) (all P < 0.001) were significantly greater in subjects with NB than in those with MB. Furthermore, intermolar width, maxillary width at the molars, intercanine width, maxillary width at the canines, and palatal area were significantly larger in subjects with NB than in those with MB (all P < 0.001). In the Skeletal Class II group, OPV, TPV (both P < 0.05) were significantly greater in subjects with NB than in those with MB. No significant differences in pharyngeal airway parameters in the MB group between subjects with Skeletal Class I and those with Skeletal Class II. CONCLUSION: Regardless of sagittal Skeletal Class I or II, the pharyngeal airway and maxillary arch in children with MB differ from those with NB. However, the pharyngeal airway was not significantly different between Skeletal Class I and II in children with MB.


Asunto(s)
Imagenología Tridimensional , Maxilar , Respiración por la Boca , Faringe , Cefalometría/métodos , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Imagenología Tridimensional/métodos , Mandíbula , Maxilar/diagnóstico por imagen , Hueso Paladar , Faringe/diagnóstico por imagen
7.
Angle Orthod ; 93(4): 467-475, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36928926

RESUMEN

OBJECTIVES: To investigate hyoid bone position and airway volume in subjects with adenoid hypertrophy, tonsillar hypertrophy, and adenotonsillar hypertrophy compared to subjects with nonobstructive adenoids or tonsils and to assess the correlation between hyoid bone and airway parameters. MATERIALS AND METHODS: A total of 121 subjects were grouped based on adenoid or tonsillar hypertrophy into four groups, as follows: (1) control group (C-group), (2) adenoid hypertrophy group (AH-group), (3) adenotonsillar hypertrophy group (ATH-group), and (4) tonsillar hypertrophy group (TH-group). Hyoid bone position and airway volumes were measured. The Kruskal-Wallis test was used for intergroup comparison, followed by pairwise comparison using the Mann-Whitney U-test. Bivariate correlation was conducted using Spearman correlation coefficients. Multiple linear regression was performed to create a model for airway volume based on hyoid bone predictive variables. RESULTS: No significant difference was found between subjects with isolated adenoid or tonsillar hypertrophy compared to the C-group. However, the ATH-group exhibited a significantly decreased hyoid bone vertical distance (HV), total airway volume (TA volume), and retroglossal airway volume (RG volume) compared to the C-group. HV and age had a high potential in terms of explaining the RG volume, whereas the TA volume and retropalatal airway volume (RP volume) models were not as successful as the RG volume counterpart. CONCLUSIONS: Subjects in ATH-group were characterized by an elevated hyoid bone position and constricted TA volume and RG volume compared to those in the C-group. HV and age were predictor variables that best explained retroglossal airway volume.


Asunto(s)
Tonsila Faríngea , Tonsila Palatina , Humanos , Tonsila Palatina/diagnóstico por imagen , Tonsila Faríngea/diagnóstico por imagen , Hueso Hioides/diagnóstico por imagen , Hipertrofia/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico
8.
J Agric Food Chem ; 68(6): 1684-1690, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31957431

RESUMEN

The carotenoid-derived volatile ß-ionone plays an important role in the formation of green and black tea flavors due to its low odor threshold, but its formation and the gene(s) involved in its biosynthesis during the tea withering process is(are) still unknown. In this study, we found that the content of ß-ionone increased during the tea withering process catalyzed by an unknown enzyme(s). Correlation analysis of expression patterns of Camellia sinensis carotenoid cleavage dioxygenase genes (CsCCDs) and the ß-ionone content during the withering period revealed CsCCD4 as the most promising candidate. The full-length CsCCD4 gene was amplified from C. sinensis, and the biochemical function of the recombinant CsCCD4 protein was studied after coexpression in Escherichia coli strains engineered to accumulate ß-carotene. The recombinant protein was able to cleave a variety of carotenoids at the 9-10 and 9'-10' double bonds. Volatile ß-ionone was detected as the main product by gas and liquid chromatography-mass spectrometry. The accumulation of ß-ionone was consistent with the expression levels of CsCCD4 in different tissues and during the withering process. The CsCCD4 expression was induced by low temperature and mechanical damage stress but not by dehydration stress. The results demonstrate that CsCCD4 catalyzes the production of ß-ionone in the tea plant and provide insight into its formation mechanism during the withering process.


Asunto(s)
Camellia sinensis/enzimología , Carotenoides/metabolismo , Dioxigenasas/metabolismo , Norisoprenoides/metabolismo , Proteínas de Plantas/metabolismo , Secuencia de Aminoácidos , Biocatálisis , Camellia sinensis/química , Camellia sinensis/genética , Camellia sinensis/metabolismo , Dioxigenasas/genética , Manipulación de Alimentos , Espectrometría de Masas , Filogenia , Hojas de la Planta/química , Hojas de la Planta/enzimología , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Plantas/clasificación , Plantas/enzimología , Plantas/genética , Alineación de Secuencia
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