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J Phys Chem Lett ; 11(3): 818-823, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31933374


All-inorganic halide perovskites are promising materials for optoelectronic applications. The surface or interface structure of the perovskites plays a crucial role in determining the optoelectronic conversion efficiency, as well as the material stability. A thorough understanding of surface atomic structures of the inorganic perovskites and their contributions to their optoelectronic properties and stability is lacking. Here we show a scanning tunneling microscopy investigation on the atomic and electronic structure of CsPbBr3 perovskite. Two different surface structures with a stripe and an armchair domain are identified, which originates from a complex interplay between Cs cations and Br anions. Our findings are further supported and correlated with density functional theory calculations and photoemission spectroscopy measurements. The stability evaluation of photovoltaic devices indicates a higher stability for CsPbBr3 in comparison with MAPbBr3, which is closely related to the low volatility of Cs from the perovskite surface.

Nanoscale ; 10(17): 7991-7998, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29610784


Atomically thin, two-dimensional (2D) indium selenide (InSe) has attracted considerable attention due to the large tunability in the band gap (from 1.4 to 2.6 eV) and high carrier mobility. The intriguingly high dependence of the band gap on layer thickness may lead to novel device applications, although its origin remains poorly understood, and is generally attributed to the quantum confinement effect. In this work, we demonstrate via first-principles calculations that strong interlayer coupling may be mainly responsible for this phenomenon, especially in the fewer-layer region, and it could also be an essential factor influencing other material properties of ß-InSe and γ-InSe. The existence of strong interlayer coupling manifests itself in three aspects: (i) indirect-to-direct band gap transitions with increasing layer thickness; (ii) fan-like frequency diagrams of the shear and breathing modes of few-layer flakes; and (iii) strong layer-dependent carrier mobilities. Our results indicate that multiple-layer InSe may be deserving of attention from FET-based technologies and may also be an ideal system to study interlayer coupling, possibly inherent in other 2D materials.

Taiwan J Obstet Gynecol ; 56(2): 165-170, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28420501


OBJECTIVE: The aim of this study was to gain a better understanding of the molecular mechanisms and identify more critical genes associated with the pathogenesis of postmenopausal osteoporosis (PMOP). MATERIALS AND METHODS: Microarray data of GSE13850 were download from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified either in B cells from postmenopausal female nonsmokers with high bone mineral density (BMD) compared with those with low BMD (defined as DEG1 group) or in B cells from postmenopausal female smokers with high BMD compared with postmenopausal female nonsmokers with high BMD (defined as DEG2 group). Gene ontology and immune-related functional enrichment analysis of DEGs were performed. Additionally, the protein-protein interaction network of all DEGs was constructed and subnetworks of the hub genes were extracted. RESULTS: A total of 51 DEGs were identified in the DEG1 group, including 30 up- and 21 downregulated genes. Besides, 86 DEGs were identified in the DEG2 group, of which 46 were upregulated and 40 were downregulated. Immune enrichment analysis showed DEGs were mainly enriched in functions of CD molecules and chemokines and receptor, and the upregulated gene interleukin 4 receptor (IL-4R) was significantly enriched. Moreover, guanine nucleotide-binding protein G (GNAI2), filamin A alpha (FLNA), and transforming growth factor-ß1 (TGFB1) were hub proteins in the protein-protein interaction network. CONCLUSION: IL-4R, GNAI2, FLNA, and TGFB1 may be potential target genes associated with the pathogenesis of PMOP. In particular, FLNA, and TGFB1 may be affected by smoking, a risk factor of PMOP.

Linfócitos B/fisiologia , Osteoporose/genética , Osteoporose/imunologia , Transcriptoma , Antígenos CD/genética , Densidade Óssea , Biologia Computacional , Bases de Dados Genéticas , Regulação para Baixo/genética , Feminino , Filaminas/genética , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/genética , Ontologia Genética , Humanos , Pós-Menopausa , Mapas de Interação de Proteínas , Receptores de Interleucina-4/genética , Fumar/genética , Fator de Crescimento Transformador beta1/genética , Regulação para Cima/genética
Aging Clin Exp Res ; 28(6): 1067-1074, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26676054


BACKGROUND: Postmenopausal osteoporosis is a common bone disease and characterized by low bone mineral density. AIM: This study aimed to reveal key genes associated with postmenopausal osteoporosis (PMO), and provide a theoretical basis for subsequent experiments. METHODS: The dataset GSE7429 was obtained from Gene Expression Omnibus. A total of 20 B cell samples (ten ones, respectively from postmenopausal women with low or high bone mineral density (BMD) were included in this dataset. Following screening of differentially expressed genes (DEGs), coexpression analysis of all genes was performed, and key genes in the coexpression network were screened using the random walk algorithm. Afterwards, functional and pathway analyses were conducted. Additionally, protein-protein interactions (PPIs) between DEGs and key genes were analyzed. RESULTS: A set of 308 DEGs (170 up-regulated ones and 138 down-regulated ones) between low BMD and high BMD samples were identified, and 101 key genes in the coexpression network were screened out. In the coexpression network, some genes had a higher score and degree, such as CSTA. The key genes in the coexpression network were mainly enriched in GO terms of the defense response (e.g., SERPINA1 and CST3), immune response (e.g., IL32 and CLEC7A); while, the DEGs were mainly enriched in structural constituent of cytoskeleton (e.g., CYLC2 and TUBA1B) and membrane-enclosed lumen (e.g., CCNE1 and INTS5). In the PPI network, CCNE1 interacted with REL; and TUBA1B interacted with ESR1. CONCLUSIONS: A series of interactions, such as CSTA/TYROBP, CCNE1/REL and TUBA1B/ESR1 might play pivotal roles in the occurrence and development of PMO.

Densidade Óssea , Osteoporose Pós-Menopausa , Idoso , Regulação para Baixo , Feminino , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/genética , Osteoporose Pós-Menopausa/fisiopatologia , Mapas de Interação de Proteínas , Regulação para Cima
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 28(2): 197-200, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24796192


OBJECTIVE: To evaluate the effectiveness of arthroscopic treatment of superior labrum anterior and posterior (SLAP) injury by absorbable anchors through anterior and posterior approach. METHODS: Between January 2010 and August 2012, 28 patients with Snyder II type of SLAP injury underwent arthroscopic operation by absorbable anchors through anterior and posterior approach. There were 15 males and 13 females, aged from 30 to 45 years (mean, 36.5 years). The left shoulder was involved in 12 cases and the right shoulder in 16 cases. All patients had a clear history of trauma. The disease duration ranged from 2 weeks to 3 years (median, 13 months). The results of O'Brien test and Speed test were positive in 25 cases and 26 cases respectively. Shoulder pain visual analogue scale (VAS) was 7.6 +/- 1.4. The Constant score of shoulder joint function was 60.2 +/- 4.3. RESULTS: Operation was successfully completed, and the incision healed well in all cases, with no complication. The follow-up time ranged from 12 to 36 months (mean, 24.5 months). The symptoms of shoulder joint interlocking, snapping, and instability disappeared. The joint pain was significantly improved. At 12 months after surgery, Constant score of shoulder joint function was 92.7 +/- 4.5, showing significant difference when compared with preoperative score (t = -30.279, P = 0.000); the shoulder pain VAS score was 1.1 + 0.9, showing significant difference when compared with preoperative score (t = 23.810, P = 0.000). At 1 year after operation, MRI examination showed complete healing in 25 cases, and high signal in 3 cases, but the pain and activity were significantly improved. CONCLUSION: Arthroscopic treatment of SLAP injury by absorbable anchors through anterior and posterior approach has the advantages of less injury, small incision, and quick recovery, so it is an ideal operation method.

Artroscopia/métodos , Articulação do Ombro/lesões , Articulação do Ombro/cirurgia , Âncoras de Sutura , Traumatismos dos Tendões/cirurgia , Implantes Absorvíveis , Adulto , Feminino , Humanos , Instabilidade Articular/cirurgia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Medição da Dor , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Articulação do Ombro/fisiopatologia , Dor de Ombro/etiologia , Dor de Ombro/cirurgia , Traumatismos dos Tendões/fisiopatologia , Resultado do Tratamento
Acta Orthop Belg ; 79(5): 502-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24350509


We describe our experience with a two-incision anterolateral acromial approach in locking plate fixation of proximal humeral fractures in older adults. Mean time between injury and surgery was 3.08 +/- 1.24 days. A proximal anterolateral transverse incision and a more distal longitudinal incision were used. A locking plate was inserted along the lateral side of the humerus from the proximal incision to the distal fragment of the humerus. Mean operation time was 62.37 +/- 19.05 minutes. There were no instances of axillary nerve paralysis or infection. Postoperative imaging results were satisfactory in all cases. Three obese patients experienced fat liquefaction at the incision site. Mean total Neer score one year after surgery was 88.16 +/- 5.05. We conclude that the two-incision anterolateral acromial approach with use of locking plates appears to be an effective means to treat proximal humeral fractures in older adults.

Fixação Interna de Fraturas/métodos , Fraturas do Ombro/cirurgia , Acidentes por Quedas/estatística & dados numéricos , Acidentes de Trânsito/estatística & dados numéricos , Idoso , Placas Ósseas , Parafusos Ósseos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos