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2.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 58(10): 971-977, 2023 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-37818530

RESUMO

Stomatognathic system rehabilitation (SSR) is an important component of dental implant therapy, involving multiple disciplines and factors. This article focuses on the importance of clinical issues, such as mandibular position, vertical distance, occlusion and temporomandibular joint in SSR, in order to provide reference for dentists in clinical diagnosis and treatment.


Assuntos
Implantes Dentários , Transtornos da Articulação Temporomandibular , Humanos , Articulação Temporomandibular , Sistema Estomatognático , Oclusão Dentária , Transtornos da Articulação Temporomandibular/cirurgia
3.
RSC Adv ; 12(32): 20423-20431, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35919158

RESUMO

High-index perovskite ferroelectric thin films possess excellent dielectric permittivity, piezoelectric coefficient, and exotic ferroelectric switching properties. They also exhibit complications in the ferroelastic domains, misfit dislocations, and strain-relaxation behaviors. Exploring the relationship of the ferroelastic domains and misfit dislocations may be of benefit for promoting the high-quality growth of these thin films. Here, the strain field of the ferroelastic domains and misfit dislocations in [101]-oriented PbTiO3/(La, Sr)(Al, Ta)O3 epitaxial thin films were investigated by advanced aberration-corrected (scanning) transmission electron microscopy (TEM) combined with geometry phase analysis (GPA). Two types of misfit dislocations with projected Burgers vectors of a[001] or a[100] on the (010) plane were elucidated, whose strain fields included in-plane strain and lattice rotation coupled with the c domains above them. Besides, it was demonstrated that the coupling was kept inside the PbTiO3 films when the film thickness was increased. Furthermore, the polarization rotation was observed in both narrow c domains and around the misfit dislocation cores, which may be attributed to the flexoelectric effect. These results are expected to provide useful information for understanding the nucleation and propagation mechanism of ferroelastic domains and for further modifying the growth of high-index ferroelectric thin films.

4.
Zhonghua Yan Ke Za Zhi ; 58(7): 506-512, 2022 Jul 11.
Artigo em Chinês | MEDLINE | ID: mdl-35796123

RESUMO

Objective: To investigate the effect of phacoemulsification on the Berger space (BS). Methods: A prospective cohort study. Patients with cataract who underwent phacoemulsification and intraocular lens implantation in the Department of Ophthalmology, Affiliated Hospital of Nantong University from May 2021 to October 2021 were enrolled. The BS was observed by slit-lamp microscopy and anterior segment optical coherence tomography (AS-OCT) before and 1 month after operation. Intraoperative optical coherence tomography with a 25G optical fiber was performed to observe the BS. The number of eyes with the BS and materials in the BS (MIB) detected perioperatively was counted, and the width of the BS was measured. Statistical analysis was carried out by the Chi-square test, generalized estimating equations, Mann-Whitney U test and binary logistic regression analysis. Results: A total of 119 patients (119 eyes) were included [44 males, 75 females; mean age, (65±12) years]. Preoperatively, the BS was identified in only 4 eyes (3.4%), and no MIB was found. Intraoperatively, the BS was identified in 47 eyes (39.5%), and the MIB was observed in 20 eyes (16.8%). At one month postoperatively, the BS was identified in 33 eyes (27.7%), of which 16 eyes (13.4%) still had MIB. There were significant differences in the detection rates of the BS and MIB between intraoperative and preoperative groups (both P<0.001). The difference in the detection rate of the BS postoperatively compared to intraoperatively was statistically significant (P=0.001), while the difference in the detection rate of MIB was not statistically significant (P>0.05). The intraoperative and postoperative width of the BS [M (Q1, Q3)] was 160.3 (61.6, 273.1) µm and 106.8 (0, 259.4) µm, respectively, and the difference was statistically significant (Z=-2.28, P=0.023). In addition, the detection rate of the BS and MIB in patients with a high risk of zonular fiber weakness [60.7% (17/28) and 42.9% (12/28)] was significantly higher than that in patients without this risk factor [33.0% (30/91) and 8.8% (8/91)] (χ²=6.90, P=0.009; P<0.001). In the multivariable model, weakness of zonular fibers (OR=0.214, 95%CI: 0.081 to 0.561) and higher cumulative dissipated energy (OR=1.255, 95%CI: 1.047 to 1.504) were the main risk factors for structural changes of the BS intraoperatively. Conclusion: Phacoemulsification can damage the normal anatomical structure of the BS, resulting in intraoperative entrance of fluid and particulates to the BS.


Assuntos
Catarata , Facoemulsificação , Idoso , Catarata/etiologia , Feminino , Humanos , Implante de Lente Intraocular/efeitos adversos , Masculino , Pessoa de Meia-Idade , Facoemulsificação/efeitos adversos , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(7): 980-984, 2022 Jul 06.
Artigo em Chinês | MEDLINE | ID: mdl-35899352

RESUMO

To provide basis for prevention and treatment by analyzing the clinical features, emotional and cognitive states and their correlations of idiopathic tinnitus. Cross-sectional study was used. Thirty-six right, 44 left, and 46 bilateral idiopathic tinnitus patients diagnosed in Beijing Tongren Hospital were prospectively enrolled from October, 2020 to February, 2022. The clinical data was recorded and the THI, DBI, STAI, and MoCA were evaluated. The clinical features and the incidence of severe tinnitus, hearing lose, anxiety, and cognitive impairment were compared by one-way ANOVA, Kruskal-Wallis H, and chi-square test. The correlation between tinnitus or hearing and emotional and cognitive states were evaluated by multivariable correlation analysis. There was no significant difference in age, BMI, years of education, tinnitus duration, and the incidence of hearing loss among groups (F=0.730,P=0.484;F=1.535,P=0.219;F=1.506,P=0.226;χ²=4.242,P=0.120;χ²=6.672,P=0.083). In right, left, and bilateral tinnitus patients, the number of severe tinnitus was 12, 7, and 20 cases and the incidence was 33.3%, 15.9%, and 43.5%; the number of depression was 13, 14, and 26 cases and incidence was 36.1%, 31.8%, and 53.5%; the number of trait anxiety was 3, 2, and 10 cases and the incidence was 8.3%, 4.5%, and 21.7%. Compared with left tinnitus patients, the incidence of severe tinnitus, depression, and trait anxiety was higher in bilateral tinnitus patients (χ²=8.139,P=0.004;χ²=5.558,P=0.018;χ²=5.753,P=0.007). The incidence of state anxiety and cognitive impairment were no significant difference among groups (χ²=0.142,P=0.931;χ²=1.338,P=0.512). The overall incidence of state anxiety and cognitive impairment were 16.7%(21/126) and 37.3%(47/126) respectively. There was positive correlation between THI score and BDI, S-AI, and T-AI scores (r=0.529,P=0.001; r=0.649,P<0.001; r=0.483,P=0.003) and negative correlation between THI and MoCA scores (r=-0.364,P=0.029) in right tinnitus group. The positive correlation was found between THI score and BDI, S-AI, and T-AI scores in left tinnitus group (r=0.508,P<0.001; r=0.506,P<0.001; r=0.357,P=0.017). The positive correlation between THI score and BDI, S-AI, and T-AI scores (r=0.753,P<0.001; r=0.527,P<0.001; r=0.536,P<0.001) and the positive correlation between tinnitus duration and MoCA score(r=0.334,P=0.023) were also found in bilateral tinnitus group.


Assuntos
Zumbido , Cognição , Estudos Transversais , Humanos , Incidência , Inquéritos e Questionários , Zumbido/diagnóstico , Zumbido/epidemiologia , Zumbido/etiologia
6.
Zhonghua Yi Xue Za Zhi ; 102(19): 1417-1422, 2022 May 24.
Artigo em Chinês | MEDLINE | ID: mdl-35599405

RESUMO

Objective: To explore the changes of cerebral blood perfusion in patients with unilateral sudden sensorineural hearing loss (SSNHL) by using the three-dimensional pseudo-continuous arterial spin labeling (3D pCASL) technique. Methods: The clinical characteristics and ASL data of the 32 patients with unilateral SSNHL were retrospectively collected from November 2020 to June 2021 in Beijing Fuxing Hospital of Capital Medical University, among them, there were 7 males and 25 females, aged from 17 to 73 (44.9±14.4) years. According to the location of SSNHL, they were divided into the left SSNHL (L-SSNHL) group (18 cases) and the right SSNHL (R-SSNHL) group (14 cases). A total of 34 healthy volunteers, which including 14 males and 20 females, aged from 24 to 68 (46.2±14.4) years were enrolled from the local community. The parameter of cerebral blood flow (CBF) of each brain area was obtained using the CereFlow software. The Brainnetome Atlas software package based on MATLAB was used for visualization. The independent-samples t test was conducted to compare the difference of cerebral blood perfusion between the unilateral SSNHL group and healthy control (HC) group. Pearson correlation analysis was used to evaluate the correlation between changes in cerebral blood perfusion and clinical scale scores. Results: The CBF of left orbital gyrus part 5, left inferior temporal gyrus part 7, right orbital gyrus part 5, right inferior temporal gyrus part 1, right inferior temporal gyrus part 7, and right parahippocampal gyrus part 3 of the L-SSNHL group were higher than that in the HC group[(49.1±8.8) vs (31.6±10.9)ml·100g-1·min-1;(42.8±14.3) vs (27.1±13.6)ml·100g-1·min-1;(51.8±9.4) vs (27.2±11.2)ml·100g-1·min-1;(38.8±5.7) vs (28.0±9.2)ml·100g-1·min-1;(38.4±13.8) vs (23.6±10.3)ml·100g-1·min-1;(42.4±9.4) vs (30.1±12.6)ml·100g-1·min-1; all P<0.05]. The CBF of left superior frontal gyrus part 7 and left middle frontal gyrus part 3 of the L-SSNHL group were lower than that in the HC group[(48.2±7.9) vs (59.3±13.7)ml·100g-1·min-1;(46.4±10.3) vs (59.3±16.9)ml·100g-1·min-1;all P<0.05]. The CBF of left orbital gyrus part 5, right orbital gyrus part 5, right inferior temporal gyrus part 1, and right inferior temporal gyrus part 7 of the R-SSNHL group were higher than that in the HC group[(50.6±7.0) vs (31.6±10.9)ml·100g-1·min-1;(50.9±8.8) vs (27.2±11.2)ml·100 g-1·min-1;(38.0±7.2) vs (28.0±9.2)ml·100g-1·min-1;(35.7±8.5) vs (23.6±10.3)ml·100g-1·min-1;all P<0.05]; the CBF of right insular part 4 was lower than that in the HC group [(44.2±6.1) vs (54.4±11.3) ml·100 g-1·min-1, P=0.018]. In the L-SSNHL group, the CBF of left superior frontal gyrus part 7 and right orbital gyrus part 5 were negatively correlated with the VAS score(r=-0.83, -0.81, all P<0.05), and the CBF of right orbital gyrus part 5 was negatively correlated with the THI score(r=-0.75, P=0.013). There was no statistically significant correlation between the remaining differences in brain regions and clinical scale scores(all P>0.05). Conclusion: Changes in cerebral blood perfusion in multiple brain regions were found in patients with unilateral SSNHL by using the 3D pCASL technique.


Assuntos
Perda Auditiva Neurossensorial , Imageamento por Ressonância Magnética , Encéfalo , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Perfusão , Estudos Retrospectivos , Marcadores de Spin
7.
Plant Dis ; 2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35285267

RESUMO

Tiller onion is a biennial herb and a fascicular variety of onion. Tiller onion has strong tillering ability and can produce up to ten bulbs per plant. It is widely cultivated due to nutrition and special flavor. In July 2020, we observed a disease that seriously affected the normal growth of tiller onion in Halahai Town, Nongan County, Jilin Province, China. At least 70% of tiller onions in the field were affected by this disease. Aboveground parts of the symptomatic plants showed stunted growth, wilting and drying. Underground parts of infected plants were shown that onion increase tiller number but did not grow and expand. Root appeared red lesions and rot in severe cases. The bulb disc appeared brown to dark brown rot. Symptomatic roots were cut into 0.5 cm pieces and surface-sterilized by dipping in 75% ethanol for 60 s, 3% NaOCl for 3 min, and rinsing three times with sterile distilled water. Pieces were placed on potato dextrose agar (PDA) plates and incubated at 25±1℃ for 4 days. Fifteen isolates were obtained and pure-cultured through single-sporing. On PDA plates, the colonies initially had white aerial mycelia that then turned pale purple. The color of the colonies on the back of the plates was purple. Macroconidia were hyaline, falcate and 14.4 to 38.7 × 1.2 to 3.0 µm. Microconidia were hyaline, reniform or elliptic, unicellular or bicellular and were 7.62 to 19.61 µm in length, and 3.23 to 8.41 µm in width. Based on these morphological and culture characteristics, the causal agent was tentatively identified as F. proliferatum. To confirm the pathogen identity, segments of the internal transcribed spacer region of the rRNA gene ( ITS, primers ITS4 and ITS5, White et al., 1990), ß-tubulin gene (TUB2, primers T1 and T2, O'Donnell and Cigelnik, 1997), and translation elongation factor 1-alpha gene (TEF-1α, primers EF1 and EF2 from O'Donnell et al., 1998) were amplified by PCR. Per the BLASTN search, TEF-1α (Accession No. OL355013), TUB2 (Accession No. OL355012), and ITS (Accession No. OL355011) queries showed 99.26%, 100%, and 99.82% homology to F. proliferatum GenBank accessions KU872098, MH398224, and MH997878, respectively. Pathogenicity of fifteen isolates of F. proliferatum from tiller onion was confirmed by inoculating healthy tiller onion roots and bulb disc with a spore suspension (1 × 106 spores/ml) produced on PDA. For each treatment, five plants were injected with 5 ml of spore suspension. Control plants (n=5) were injected with sterilized water. All plants were enclosed in plastic bags for 48 h in a greenhouse at 28℃ and 12 h/d light cycle. After 10 days, inoculated plants showed similar symptoms to those on the original diseased plants, while control plants remained symptomless. F. proliferatum was successfully re-isolated from symptomatic plants to fulfill Koch's postulates. Diseases caused by F. proliferatum are only reported in A. cepa. To our knowledge, this is the first report of F. proliferatum in Allium cepa L. var. agrogatum Don in China. Our findings are important for informed surveillance of the disease in China as F. proliferatum infection can not only reduce the quality and yield of tiller onion but also can contaminate the bulbs with harmful mycotoxins.

8.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(2): 168-172, 2022 Feb 09.
Artigo em Chinês | MEDLINE | ID: mdl-35152653

RESUMO

Objective: To compare the accuracy of photogrammetry and conventional impression techniques for complete-arch implant rehabilitation. Methods: An edentulous maxillary stone cast containing 8 screw-retained implant abutment replicas was derived from a 74-year-old male patient who visited the Department of Dental Implant Center, Capital Medical University School of Stomatology in September 2019. The stone cast was copied through the open-tray splinted impression, and the copied cast was used as the master cast for this study. The abutment-level impressions of master cast were made by photogrammetry (PG) and the conventional impression technique (CNV) by one attending doctor. Group PG: after which scan bodies were connected to each implant replica, a photogrammetry system was used to obtain digital impressions of the master cast (n=10); Group CNV: conventional open-tray splinted impression technique was performed to fabricate conventional definitive casts (n=10). After connecting the scan bodies onto each implant replicas, the master cast and the 10 definitive casts from group CNV were digitized with a laboratory reference scanner. All data of group PG, group CNV and mater cast were saved as ".stl" files. For all test scans and reference scan, the three-dimensional information of scan bodies were converted to implant abutment replicas using a computer aided design software (Exocad). The data of the group PG and the group CNV were respectively registered with the reference data (trueness analysis) and pairwise within group (precision analysis) for accuracy evaluation in a three-dimensional analysis software (Geomagic Control X). Results: The trueness and precision of group PG [(17.33±0.34) and (2.50±0.79) µm ] were significantly statistically better than those of group CNV [(24.30±4.16) and (26.12±4.54) µm] respectively (t=-5.29 and -34.35, P<0.001). Conclusions: For complete-arch implant abutment-level impression, photogrammetry produces significantly better accuracy than conventional impression technique.


Assuntos
Implantes Dentários , Técnica de Moldagem Odontológica , Idoso , Desenho Assistido por Computador , Materiais para Moldagem Odontológica , Humanos , Modelos Dentários , Fotogrametria
9.
Zhonghua Yi Xue Za Zhi ; 101(39): 3195-3201, 2021 Oct 26.
Artigo em Chinês | MEDLINE | ID: mdl-34689530

RESUMO

Objective: To determinate the range of quantitative myocardial perfusion parameters (MBF, MBV) in subjects without coronary artery lesions by dynamic computed tomography myocardial perfusion imaging (CTP). Methods: Subjects with occasional chest tightness or family history of coronary artery disease coming to Fuwai Hospital underwent coronary computed tomography angiography (CCTA) were prospectively enrolled. A total of 34 subjects [mean age (50±7) years, range from 33 to 65 years; 15 male and 19 female] were enrolled. Coronary lesions were not confirmed in any subjects using CCTA and volunteered for stress and rest dynamic CTP examination. MBF and MBV values were calculated in each myocardial segment using a 17-segment model. The global ranges of MBF and MBV were analyzed, and the gender variability and regional variability were compared. Results: The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g-1·min-1, (212.8±40.8) ml·100 g-1·min-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g, respectively. The absolute and resolute reserves of MBF and MBV [(102.8±41.5) ml·100 g-1·min-1, 107.7%±52.5%; (9.3±5.2) ml/100 g, 62.1%±47.4%] were highest in the right coronary artery territory, but without any significant differences. The stress MBF and absolute reserve of MBF in females were higher than those of males [(228.6±39.9) ml·100 g-1·min-1, (113.3±46.2) ml·100 g-1·min-1; (192.8±33.4) ml·100 g-1·min-1, (77.0±41.2) ml·100 g-1·min-1] (both P<0.05). The MBF resolute reserve, rest MBV, stress MBV and MBV absolute and resolute reserves were higher in females, but without significant differences (all P>0.05). Conclusion: The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g-1·min-1, (212.8±40.8) ml·100 g-1·min-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g. The MBF under stress perfusion and MBF absolute reserve of females are higher than those of males.


Assuntos
Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Adulto , Idoso , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Perfusão , Valor Preditivo dos Testes
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(2): 278-283, 2021 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-33626616

RESUMO

Objective: To understand the current status of HIV self-testing reagent use in pre-exposure prophylaxis (PrEP) and related factors in men who have sex with men (MSM). Methods: From December 2018 to December 2019, "Gold data" online platform (www.jinshuju.com) was used to conduct multicenter PrEP studies in Shenyang, Beijing, Chongqing and Shenzhen of China. Results: A total of 1 222 MSM PrEP users were included in the multicenter study. The average age of the participants was (31.5±8.7) years, and the number of sexual partners in the past three months was 3 (P25,P75:2,6). The proportions of those who did not use condoms in anal sex with fixed, casual and commercial partners were 62.7% (456/727), 56.3% (440/781) and 41.0% (16/39), respectively. Up to 74.5% (910/1 222) of participants had used HIV self-testing reagents, and the number of HIV self-testing during last year was 3 (P25,P75:2,5). The multivariate logistic regression analysis indicated that compared with age group >40 years, those with education level of junior high school or below, those with psychological identity as female, event driven PrEP users, those never using new type drugs in past 3 months, the participants aged 18- years (aOR=2.06, 95%CI: 1.35-3.14), 26- years (aOR=2.72, 95%CI: 1.77-4.17), 31- years (aOR=1.76, 95%CI: 1.19-2.59), undergraduates (aOR=2.18, 95%CI: 1.35-3.49), graduate students and above (aOR=3.06, 95%CI: 1.69-5.54), those with psychological identity as male (aOR=3.22, 95%CI: 1.55-6.70), daily PrEP users (aOR=1.35, 95%CI: 1.03-1.78), and new type drug users in the past three months (aOR=1.72, 95%CI: 1.30-2.28) had higher proportions of HIV self-testing behaviors. Conclusions: The proportion of HIV self-testing in MSM PrEP users was high, while it was relatively low in older age group, event driven PrEP users and MSM never using new type drugs. To assess and improve the effectiveness and compliance of PrEPs, it is necessary to provide better HIV self-testing service for MSM with low HIV self-testing rate.


Assuntos
Infecções por HIV , Homossexualidade Masculina , Profilaxia Pré-Exposição , Autoteste , Adolescente , Adulto , China , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Indicadores e Reagentes , Masculino , Fatores Socioeconômicos , Adulto Jovem
11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(11): 891-896, 2020 Nov 09.
Artigo em Chinês | MEDLINE | ID: mdl-33171564

RESUMO

Objective: To evaluate the clinical outcomes of digital technique-aided occlusal rehabilitation based on implant-supported fixed prostheses (ISFP), and to provide some information for clinical application of digital technique. Methods: Retrospectively reviewed the cases which had used neuromuscular system and condylar movement tracing device to reconstruct occlusion in one or double jaw fully edentulous ISFP from January, 2013 to January, 2020. A total of 6 eligible patients were enrolled in the present study with 56 implants and 8 ISFP, including 4 male patients and 2 female patients, aged from 43 to 74 years. The clinical outcomes were evaluated in four aspects, including implant survival rate, implants success rate, marginal bone loss and the occurrence of prosthesis complications. Results: The follow-up time was (4.0±2.2) years (1-7 years). The implant survival rate was 100% (56/56) and the implant success rate was 98% (55/56), with an average missal and distal marginal bone loss of (0.04±0.11) mm/year. Veneer chipping occurred at incisal edge of 2 adjacent incisors in only one prosthesis 3 years after rehabilitation. Conclusions: Combination of digital techniques of neuromuscular system and condylar movement tracing device to assist occlusal rehabilitation based on ISFP showed a high implant success rate. The complication seldom happened. Long and stable occlusion has been observed. The clinical outcomes were favorable.


Assuntos
Implantes Dentários , Arcada Edêntula , Boca Edêntula , Adulto , Idoso , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Feminino , Seguimentos , Humanos , Arcada Edêntula/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
J Phys Chem Lett ; 11(17): 7015-7020, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32786653

RESUMO

Vacancy diffusion is fundamental to materials science. Hydrogen atoms bind strongly to vacancies and are often believed to retard vacancy diffusion. Here, we use a potential-of-mean-force method to study the diffusion of vacancies in Cu and Pd. We find H atoms, instead of dragging, enhance the diffusivity of vacancies due to a positive hydrogen Gibbs excess at the saddle-point: that is, the migration saddle attracts more H than the vacancy ground state, characterized by an activation excess ΓHm ≈ 1 H, together with also-positive migration activation volume Ωm and activation entropy Sm. Thus, according to the Gibbs adsorption isotherm generalized to the activation path, a higher µH significantly lowers the migration free-energy barrier. This is verified by ab initio grand canonical Monte Carlo simulations and direct molecular dynamics simulations. This trend is believed to be generic for migrating dislocations, grain boundaries, and so on that also have a higher capacity for attracting H atoms due to a positive activation volume at the migration saddles.

13.
Nat Mater ; 19(8): 881-886, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32483242

RESUMO

A topological meron features a non-coplanar structure, whose order parameters in the core region are perpendicular to those near the perimeter. A meron is half of a skyrmion, and both have potential applications for information carrying and storage. Although merons and skyrmions in ferromagnetic materials can be readily obtained via inter-spin interactions, their behaviour and even existence in ferroelectric materials are still elusive. Here we observe using electron microscopy not only the atomic morphology of merons with a topological charge of 1/2, but also a periodic meron lattice in ultrathin PbTiO3 films under tensile epitaxial strain on a SmScO3 substrate. Phase-field simulations rationalize the formation of merons for which an epitaxial strain, as a single alterable parameter, plays a critical role in the coupling of lattice and charge. This study suggests that by engineering strain at the nanoscale it should be possible to fabricate topological polar textures, which in turn could facilitate the development of nanoscale ferroelectric devices.

14.
J Phys Chem Lett ; 11(7): 2637-2646, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32188242

RESUMO

To have a fully first-principles description of the moiré pattern in transition-metal dichalcogenide heterobilayers, we have carried out density functional theory calculations on a MoTe2(9 × 9)/MoS2(10 × 10) stacking, which has a superlattice larger than an exciton yet not large enough to justify a continuum model treatment. Lattice corrugation is found to be significant in both monolayers, yet its effect on the electronic properties is marginal. We reveal that the variation of the average local potential near Mo atoms in both MoTe2 and MoS2 layers displays a conspicuous moiré pattern. They are the intralayer moiré potentials correlating closely with the spatial variation of the valence band maximum and conduction band minimum. The interlayer moiré potential, defined as the difference between the two intralayer moiré potentials, changes roughly in proportion to the band gap variation in the moiré cell. This finding might be instructive in chemical engineering of van der Waals bilayers.

15.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 38(12): 919-921, 2020 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-33406553

RESUMO

Objective: To explore the feasibility of soft copy image of chest digital radiography (DR(SC)) in pneumoconiosis diagnosis by observing the reading effect of DR(SC) and comparing it with high kV film-screen chest radiography (FSR(HkV)) . To provide a basis for the establishment of a regional information network platform for pneumoconiosis diagnosis. Methods: A total of 119 miners who were exposed to silica dust and engaged in copper or lead-zinc mining were collected by the Third People's Hospital of Yunnan from October 2017 to August 2019. The pulmonary X-ray findings of DRSC and FSR(HkV) in each case were independently judged and diagnosed by three experienced diagnostic physicians, and the final decision was made according to the consensus of most doctors. The consistency of the two imaging methods was analyzed by observing the main small opacity shape, the overall density, the range of distribution, the aggregation of the small opacity and the big opacity, and the diagnosis stage. Results: there were 118 males and 1 female with an average age of 46.21 years. Average exposure time 7.38 years. The pulmonary X-ray findings of 113 cases with two imaging methods were mainly the round small opacity of p,q and r,but the reticular irregular opacity were not prominent, Only one case of FSR(HkV) judgment p shape and DR(SC) judgment q shape were observed, The coincidence rate was 99.12% (112/113) . huger opacity were observed in the other 6 cases. The coincidence rate was 95.51% (4/89) between pneumoconiosis-free and stageⅠ, and there was no significant difference between stageⅡand stage Ⅲ (30/30, P>0.05) . Conclusion: The x-ray findings of Silicosis with small round shadow in lung can be used by DR(SC) in diagnosis and staging.


Assuntos
Pneumoconiose , Silicose , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumoconiose/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Radiografia , Radiografia Torácica , Silicose/diagnóstico por imagem
16.
Acta Gastroenterol Belg ; 82(3): 397-400, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31566327

RESUMO

BACKGROUND AND AIMS: Early prediction of severe acute pancreatitis (SAP)would be helpful for triaging patients to the appropriate level of care and intervention. The aim of this study is to compare the performance of the Change in Amylase And Body mass index (CAB) score and BISAP score for predicting SAP. PATIENTS AND METHODS: A total of 406 with AP were enrolled. The age, gender, body mass index(BMI), blood urea nitrogen determined at the time of admission and serum amylase determined on day 1 and day 2 after hospitalization were collected and analyzed statistically. RESULTS: Multivariable analysis confirmed that blood urea nitrogen (OR 1.06; 95%CI 1.03-1.09) and percentage change in amylase day 2 (OR 0.75; 95%CI 0.65-0.87) were independently associated with development of SAP. No statistically significant association was observed between BMI (OR 1.04; 95%CI 0.951.13) and severity of acute pancreatitis. The area under the receiver operating characteristic curve for Body mass index (BMI), percentage change in amylase day 2, BISAP score and CAB score were 0.57±0.05, 0.68±0.04, 0.84±0.03 and0.53±0.05, respectively. CONCLUSION: BISAP is more accurate for predicting the severity of acute pancreatitis than the CAB score.


Assuntos
Amilases/sangue , Nitrogênio da Ureia Sanguínea , Índice de Massa Corporal , Pancreatite/diagnóstico , Índice de Gravidade de Doença , Doença Aguda , Biomarcadores/sangue , Humanos , Pancreatite/classificação , Pancreatite/patologia , Admissão do Paciente/estatística & dados numéricos , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos
17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(11): 1501-1506, 2018 Nov 10.
Artigo em Chinês | MEDLINE | ID: mdl-30462962

RESUMO

Objective: To analyze and reveal the distribution, research hotspots and study trend of worldwide published articles correlated with HIV/AIDS post-exposure prophylaxis (PEP), and provide information for related studies in China. Methods: CiteSpace software 5.1 was used to visualize all related papers in the web of science database published during 2000-2017. Results: The average growth rate of international PEP-related papers was 10.78%,and number of published papers in 2016 was highest (n=34), relevant research hotspots have shifted from the prevention of occupational HIV exposure to the prevention of non-occupational HIV exposure in group at high risk, such as MSM, in recent years. Clustering analysis classified research hotspots into three categories, including risk reduction through enhanced intervention, current status of global HIV PEP and German-Austrian Recommendation. Conclusions: Non-occupational HIV PEP in groups at high-risk, especially MSM, has received increasing attention in recent years, the research of PEP mainly focus on improving the awareness and use of PEP in MSM and compliance in the course of medication. In the context of severe HIV epidemic in MSM without effective control in China, PEP should be strengthened to assess and explore the risk of HIV infection in MSM to provide reference for medical personnel and related departments to implement HIV non-occupation exposure blockade and formulate PEP medication.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Bibliometria , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Publicações Periódicas como Assunto , Profilaxia Pós-Exposição , Pesquisa Biomédica , China , HIV , Infecções por HIV/epidemiologia , Humanos , Masculino , Profilaxia Pós-Exposição/métodos
18.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(10): 1362-1367, 2018 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-30453438

RESUMO

Objective: To understand the impact of HIV and Mycobacterium tuberculosis (MTB) co-infectious (HIV/MTB) on related mortality in Guangxi Zhuang Autonomous Region, provide evidence for the development of a better HIV/MTB co-infection control and prevention program. Methods: A multiple cross-systems check (MCSC) approach was used to confirm the HIV/MTB co-infection individuals on data related to treatment, follow-up, epidemiological comprehensive and Tuberculosis (TB) special report system. Social demography characteristics, incidence of TB among HIV positive individuals, HIV incidence among MTB infection persons etc., were described. We compared the mortalities and related risks between HIV/MTB co-infection and mono HIV positive individuals as well as between the HIV/MTB co-infection and mono MTB infection persons, using both the Chi Square test and the Cox's proportional hazard regression model (Cox). Results: Reported data showed that the incidence of MTB co-infection in the HIV cohort was 17.72% (2 533/14 293), while HIV incidence in the TB patients was 5.57% (2 351/42 205), respectively. The mortality of HIV/MTB co-infection in the HIV/AIDS cohort was 15.16% (384/2 533) within one-year of observation and was significantly higher than the mortality (13.63%,1 603/11 760) of mono HIV positive individuals (P<0.000 1). The percentage of the HIV/AIDS death cases was 19.33% (384/1 987) who registered and died in the 2011 calendar year were caused by MTB co-infection. Among all the HIV/MTB co-infection patients who had been identified from the HIV cohort, 60.05% (1 521/2 533) had initiated ART, 15.48% (392/2 533) had been cured for TB and 27.48% (696/2 533) had been under complete TB regimen. Among the confirmed HIV/MTB cases from the TB cohort, the cure rate of TB was 19.70% (463/2 351) and the percentage of completed TB regimen was 37.26% (876/2 351). The percentage of the individuals whose CD(4)(+) T lymphocyte cells count appeared less than 200 cell/µl was 64.13% (785/1 224), upon the HIV diagnoses were made. Compared with individuals who were under mono HIV infection, the mortality risk on HIV/MTB co-infection was 1.17 times higher during the five-year observation period, then the patients with only mono MTB infection and the mortality risk in patients with HIV/MTB co-infection was 25.68 times higher under the 12-month observation period. Conclusions: Both the incidence and mortality of HIV/MTB appeared high in Guangxi, with mortality and the risk of mortality in the HIV/MTB co-infection group significantly higher than that in both the HIV mono infection and the MTB mono infections groups. Both the rate of antiretroviral treatment coverage and the cure rate of TB treatment should be increased in no time as well as the capability of early TB case-finding among people living with HIV.


Assuntos
Coinfecção/epidemiologia , Infecções por HIV/mortalidade , HIV , Mycobacterium tuberculosis , Tuberculose/mortalidade , China/epidemiologia , Feminino , Infecções por HIV/etnologia , Infecções por HIV/virologia , Humanos , Masculino , Tuberculose/etnologia , Tuberculose/virologia
19.
Zhonghua Yu Fang Yi Xue Za Zhi ; 52(11): 1173-1176, 2018 Nov 06.
Artigo em Chinês | MEDLINE | ID: mdl-30419704

RESUMO

Objective: To investigation the situation of cold chain on vaccine in parts of Zhejiang Province and to provide recommendations for the management. Methods: From October to December, 2016, we each selected an immunization clinic in Cangnan County of Wenzhou, Yongkang City of Jinhua, Jianggan District of Hangzhou. Temperature recorder and vaccine viral monitor (VVM) labels were used to monitor the cold chain during all the storage and transportation process. In Jianggan District, we use optical density sensor to detected 20 VVM labels every time when the vaccine was stock in and out. Results: In total, 54 958 records were collected by temperature recording devices in all the three immunization clinic. 275 records exceeded the temperature limit required for store and transportation, of which 270 (98.2%) were above 8 ℃ and 5 (1.9%) were under 2 ℃. Excessive temperature exposure mainly occurred during the transportation (38.2%, n=105), followed by storage process in CDCs at different levels (26.2%, n=72), stock in and out (20.7%, n=50) and storage in the refrigerators in immunization clinics (14.9%, n=41). The average optical density difference between VVM labels and the reference circular decreased from 0.404 to 0.344 when the vaccines were delivered from the Zhejiang provincial CDC to immunization clinics. The color of VVMs did not significantly changed before use. Conclusions: The potential risk of vaccine cold chain in the monitoring sites is over-temperature. The weak links of cold chain management include the transportation, storage process, and stock in and out.


Assuntos
Armazenamento de Medicamentos/métodos , Refrigeração , Vacinas , China , Humanos
20.
HIV Med ; 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-29923304

RESUMO

OBJECTIVES: The HIV epidemic is worsening among men who have sex with men (MSM) in China, especially among those who are younger than 25 years old [younger MSM (YMSM)]. The aim of the study was to compare the prevalences of HIV incidence and recent HIV infection as well as factors associated with recent HIV infection in YMSM and older MSM (OMSM). METHODS: A multicentre cross-sectional survey was conducted among 4496 MSM recruited from seven Chinese cities. YMSM were defined as those aged < 25 years. Data on demographics and sexual behaviours were collected using structural questionnaires. Blood samples were tested for recent HIV infection and other sexually transmitted infections. RESULTS: Among the participants, 1313 were YMSM and 3183 were OMSM. Compared with OMSM, YMSM had a higher prevalence of recent HIV infection [5.4% (71 of 1313) for YMSM vs. 3.6% (115 of 3175) for OMSM; P = 0.006] and a higher HIV incidence [11.8 per 100 person-years (PY) (95% confidence interval (CI) 9.0-14.5) for YMSM vs. 7.6 per 100 PY (95% CI 6.3-9.0) for OMSM]. The incidence increased with age among YMSM, especially between the ages of 16 and 21 years. In contrast, the incidence declined with age among OMSM. Anal bleeding, recreational drug use, syphilis and herpes simplex virus 2 (HSV-2) infection were independent risk factors for recent HIV infection among YMSM. The prevalence of all these risk factors increased with age between the ages of 16 and 21 years. Anal bleeding (19.8%) and recreational drug use (19.5%) had the highest adjusted population attributable fractions (aPAFs) among YMSM. The highest aPAFs of anal bleeding (27.4%) and syphilis infection (25.5%) were found between the ages of 19 and 21 years. CONCLUSIONS: The HIV incidence in Chinese YMSM was significantly higher than that in OMSM. YMSM aged 16-21 years had an extremely high risk of recent HIV infection.

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