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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(1): 47-53, 2020 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-31914569

RESUMO

Objective: To understand the health literacy and relevant factors of cancer prevention consciousness in Chinese urban residents from 2015 to 2017. Methods: A cross-sectional survey was conducted in 16 provinces covered by the Cancer Screening Program in Urban China from 2015 to 2017. A total of 32 257 local residents aged ≥18 years old who could understand the investigation procedure were included in the study by using the cluster sampling method and convenient sampling method. All local residents were categorized into four groups, which contained 15 524 community residents, 8 016 cancer risk assessment/screening population, 2 289 cancer patients and 6 428 occupational population, respectively. The self-designed questionnaire was used to collect the information of demographic characteristics and cancer prevention consciousness focusing on nine common risk factors, including smoking, alcohol, fiber food, food in hot temperature or pickled food, chewing betel nut, helicobacter pylori, moldy food, hepatitis B infection, estrogen, and exercise. The logistic regression model was adopted to identify the influencing factors. Results: The overall health literacy of the cancer prevention consciousness was 77.4% (24 980 participants), with 77.4% (12 018 participants), 79.9% (6 406 participants), 77.2% (1 766 participants) and 74.5% (4 709 participants) in each group (P<0.001). The correct response rates for nine risk factors ranged from 55.2% to 93.0%. The multivariate logistic regression analysis showed that compared with community residents, people with primary school level education or below, and the number of people living together in the family <3, the cancer risk assessment/screening intervention population, cancer patients, those with junior high school level educationor above and the number of people living in the family ≥3 had better health literacy of the cancer prevention consciousness (all P values <0.05). Compared with females, 39 years old and below, government-affiliated institutions or civil servants, from the eastern region, males, older than 40 years, company or enterprise employees, and from the middle or western region had worse health literacy of the cancer prevention consciousness (all P values <0.05). Conclusion: The health literacy of the cancer prevention consciousness in Chinese urban residents should be improved. The cancer screening intervention, gender, age, education, occupation, the number of people co-living in the family, and residential region were associated with the health literacy of the cancer prevention consciousness.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Alfabetização em Saúde/estatística & dados numéricos , Neoplasias/prevenção & controle , População Urbana , Adolescente , Adulto , China , Estudos Transversais , Feminino , Humanos , Masculino , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(1): 54-61, 2020 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-31914570

RESUMO

Objective: To understand the consciousness of the cancer early detection among urban residents and identify the influencing factors from 2015 to 2017. Methods: A cross-sectional survey was conducted in 16 provinces covered by the Cancer Screening Program in Urban China from 2015 to 2017. A total of 32 257 local residents aged ≥18 years old who could understand the investigation procedure were included in the study by using the cluster sampling method and convenient sampling method. All local residents were categorized into four groups, which contained 15 524 community residents, 8 016 cancer risk assessment/screening population, 2 289 cancer patients and 6 428 occupational population, respectively. Self-designed questionnaires were used to collect population, socioeconomic indicators, self-cancer risk assessment, regular participation in physical examination and other information. The multivariate logistic regression model was used to identify the factors of people who had not regularly participated in the regular physical examination in the past five years. Results: The self-assessment results of 32 357 residents showed that there were 27.54% (8 882) of total study population with self-reported cancer risk, 45.48% (14 671) without cancer risk and 26.98% (8 704) with unclear judgement on their own cancer risk. Among population with cancer risk, 79.84% (7 091) considered physical examination accounted. In the past five years, there were 21 105 (65.43%) residents participated in regular physical examination and 11 148 (34.56%) participated in non-scheduled one, respectively. The multivariate logistic regression analysis showed that compared with unmarried and western region residents, divorced, middle and eastern region residents had a stronger consciousness to participate in the regular physical examination (P<0.05). Compare with residents with annual household income less than 20 000 CNY in 2014, cancer risk assessment/screening intervention population, and self-assessment with cancer risk, residents with annual household income between 20 000 CNY and 59 000 CNY in 2014, occupational population, community residents, cancer patients, self-reported cancer-free risk, and self-assessment with unclear judgement of cancer risk were less likely to participate in the regular physical examination (all P values <0.05). Conclusion: From 2015 to 2017, the Chinese urban residents had a acceptable consciousness of the cancer early detection. The marital status, annual household income, population group and self-assessment of cancer risk were related to the consciousness of the cancer early detection of people who had not participated in the regular physical examination in the past five years.


Assuntos
Detecção Precoce de Câncer/psicologia , Conhecimentos, Atitudes e Prática em Saúde , População Urbana , Adolescente , Adulto , China , Estudos Transversais , Humanos , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(1): 62-68, 2020 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-31914571

RESUMO

Objective: To understand the consciousness of the cancer early diagnosis among urban residents and identify the related factors from 2015 to 2017. Methods: A cross-sectional survey was conducted in 16 provinces covered by the Cancer Screening Program in Urban China from 2015 to 2017. A total of 32 257 local residents aged ≥18 years old who could understand the investigation procedure were included in the study by using the cluster sampling method and convenient sampling method. All local residents were categorized into four groups, which contained 15 524 community residents, 8 016 cancer risk assessment/screening population, 2 289 cancer patients and 6 428 occupational population, respectively. The general demographic characteristics, the consciousness of the cancer early diagnosis (whether people would have a willingness or encourage their relatives/friends to confirm the abnormal results once which were detected from the physical examination) and other information were collected by using the self-designed questionnaire. The non-conditional logistic regression model was used to identify the relateol factors related to the consciousness of the cancer early diagnosis. Results: As for residents with abnormal result from the physical examination, 89.29% (28 802) of residents would choose to seek medical treatment for further diagnosis. If their relatives/friends had abnormal results from the physical examination, 89.55% (28 886) of residents would encourage their relatives/friends to confirm the diagnosis in time. The non-conditional logistic regression model analysis showed that compared with the public institution staff/civil servants, annual household income less than 20 000 CNY, the western region and the cancer risk assessment/screening intervention population, the company staff, annual household income about 40 000 CNY and more, and the residents from the middle and eastern region had a stronger consciousness to seek further diagnosis; while the unemployed residents and community residents were less likely to seek further diagnosis (P<0.05). Conclusions: From 2015 to 2017, the Chinese urban residents had a good consciousness of the cancer early diagnosis. Occupation, annual household income, residential region and population group were related to the consciousness of the cancer early diagnosis.


Assuntos
Detecção Precoce de Câncer/psicologia , Conhecimentos, Atitudes e Prática em Saúde , População Urbana , Adolescente , Adulto , China , Estudos Transversais , Humanos , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(1): 69-75, 2020 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-31914572

RESUMO

Objective: To understand the consciousness of the cancer early treatment and its demographic and socioeconomic factors. Methods: A cross-sectional survey was conducted in 16 provinces covered by the Cancer Screening Program in Urban China (CanSPUC) from 2015 to 2017. A total of 32 257 local residents aged ≥18 years old who could understand the investigation procedure were included in the study by using the cluster sampling method and convenient sampling method. All local residents were categorized into four groups, which contained 15 524 community residents, 8 016 cancer risk assessment/screening population, 2 289 cancer patients and 6 428 occupational population, respectively. The questionnaire collected personal information, the consciousness of the cancer early treatment and relevant factors. The Chi square test was used to compare the difference between the consciousness of the cancer early treatment and relevant factors among the four groups. The logistic regression model was used to analyze the influencing factors related to the consciousness of the cancer early treatment. Results: With the assumption of being diagnosed as precancer or cancer, 89.97% of community residents, 91.84% of cancer risk assessment/screening population, 93.00% of cancer patients and 91.52% of occupational population would accept active treatments (P<0.001). If the immediate family members were diagnosed as precancer or cancer, people who would encourage their family members to receive early treatment in the four groups accounted for 91.96%, 91.94%, 92.44% and 91.55%, respectively (P<0.001). The company employees, annual household income with 40 000 yuan and more and other three groups had a relatively better consciousness of the cancer early treatment (P<0.05). Male, widowed, unemployed and from the central and western regions had a relatively worse consciousness of the cancer early treatment (P<0.05). Conclusion: Residents in urban China participants had a good consciousness of the cancer early treatment. The marital status, occupation, annual household income and residential regions were major factors related to the consciousness of the cancer early treatment.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Neoplasias/terapia , Tempo para o Tratamento/estatística & dados numéricos , População Urbana , Adolescente , Adulto , China , Estudos Transversais , Feminino , Humanos , Masculino , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(1): 76-83, 2020 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-31914573

RESUMO

Objective: To understand the health literacy of the cancer prevention and treatment among urban residents of China, and explore the related factors. Methods: A cross-sectional survey was conducted in 16 provinces covered by the Cancer Screening Program in Urban China (CanSPUC) from 2015 to 2017. A total of 32 257 local residents aged ≥18 years old who could understand the investigation procedure were included in the study by using the cluster sampling method and convenient sampling method. All local residents were categorized into four groups, which contained 15 524 community residents, 8 016 cancer risk assessment/screening population, 2 289 cancer patients and 6 428 occupational population, respectively. The health literacy of the cancer prevention, early discovery, early diagnosis, early treatment and the demands of cancer prevention and treatment knowledge was analyzed. The level of health literacy among different groups were calculated and compared. The binary logistic regression model was used to analyze the influencing factors of the health literacy of the cancer prevention and treatment. Results: The level of health literacy of the cancer prevention and treatment was 56.97% among all study population; in each group it was 55.01% for community residents, 59.08% for cancer risk assessment/screening population, 61.99% for cancer patients and 57.31% for occupational population, respectively (P<0.001). The level of health literacy of the cancer prevention and treatment of residents aged 50 to 69 years old, other occupational groups, unmarried, the central and western region residents and the group with unclear self-assessment of cancer risk was significantly lower than that of residents younger than 40 years old, personnel of public institutions/civil servants, married, the eastern region residents and the group whose self-assessment without cancer risk (P<0.05) . The level of health literacy of cancer prevention and treatment of females, people who went to high school or over, cancer risk assessment/screening population, cancer patients and occupational population was significantly higher than that of males, people who had an education level of primary school or below and community residents (P<0.05) . Conclusion: The health literacy of the cancer prevention and treatment of urban residents in China was relatively high, but there was still room for improvement. Gender, age, educational level, occupation, region, marital status, self-assessment of cancer risk, and type of respondents were the key influencing factors of the health literacy of the cancer prevention and treatment. Male, 50-69 years old, lower educational level, central and western regions, unclear cancer risk self-assessment, and without specific environmental exposure to cancer prevention and treatment knowledge or related risk factors were the characteristics of the key intervention group of the health literacy of the cancer prevention and treatment.


Assuntos
Alfabetização em Saúde/estatística & dados numéricos , Neoplasias/prevenção & controle , População Urbana , Adolescente , Adulto , Idoso , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(1): 84-91, 2020 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-31914574

RESUMO

Objective: To investigate the demand and access to the cancer prevention and treatment knowledge and related factors among urban residents in China from 2015 to 2017. Methods: A cross-sectional survey was conducted in 16 provinces covered by the Cancer Screening Program in Urban China from 2015 to 2017. A total of 32 257 local residents aged ≥18 years old who could understand the investigation procedure were included in the study by using the cluster sampling method and convenient sampling method. All local residents were categorized into four groups, which contained 15 524 community residents, 8 016 cancer risk assessment/screening population, 2 289 cancer patients and 6 428 occupational population, respectively. The self-designed questionnaire was used to collect the information of general demographic characteristics, the demand and access to cancer prevention and treatment knowledge, and the influencing factors of the attitude. The Chi-square test was used to analyze the difference of the demand of the cancer prevention knowledge among different groups and the corresponding factors of the cancer prevention and treatment knowledge were analyzed by using the logistic regression model. Results: The proportion of residents who need the cancer prevention and treatment knowledge was 79.5%. The demand rate of the inducement, symptom and diagnosis methods of cancer in the occupational population was highest, about 66.8%, 71.0% and 20.8%, respectively. The demand rate of treatment methods and cost in current cancer patients was the highest, about the 45.9% and 21.9%, respectively. The top three sources to acquire the cancer prevention and treatment knowledge were "broadcast or television" (69.5%), "books, newspapers, posters or brochures" (44.7%) and "family and friends" (33.8%). The multivariate analysis showed that compared with public institution personnel/civil servants, unmarried/cohabiting/divorced/widowed and others, annual household income less than 20 000 CNY, from the eastern region, people without cancer diagnosis and people with self-assessment of cancer risk, the demand rate of cancer prevention and treatment knowledge was higher in enterprise personnel/workers, married, annual household income between 60 000 CNY and 150 000 CNY, from the central region, people with cancer and people with unclear cancer risk (all P values <0.05). Conclusion: There was a high demand for the cancer prevention and treatment knowledge among urban residents in China from 2015 to 2017. The main access to the knowledge is from the radio or television. The occupation, marital status, annual household income, residential region, health status and risk of disease were the main factors of the demand of the cancer prevention and treatment knowledge.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Acesso aos Serviços de Saúde/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Neoplasias/prevenção & controle , População Urbana , Adolescente , Adulto , China , Estudos Transversais , Humanos , Fatores Socioeconômicos , Inquéritos e Questionários , População Urbana/estatística & dados numéricos
7.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 54(10): 707-711, 2019 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-31607010

RESUMO

With the emergence and development of new dental materials, chairside computer aided design/computer aided manufacture (CAD/CAM) materials, as an important part of digital technology, is gaining increasing progress to meet the needs of implant restorations and digital processing technology for the mechanical properties, chemical stability, biocompatibility and processing properties. A large number of in-vitro experiments and clinical studies have been reported on various materials, such as polycrystalline ceramic, glass ceramic and indirect composite. The purpose of this article is to review the performance, the clinical indications and applications of the CAD/CAM materials for chairside digital workflow in implant prosthodontics.


Assuntos
Projeto Auxiliado por Computador , Planejamento de Prótese Dentária , Prostodontia , Materiais Dentários , Fluxo de Trabalho
8.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 54(1): 3-9, 2019 Jan 09.
Artigo em Chinês | MEDLINE | ID: mdl-30630252

RESUMO

Objective: To establish a quantitative three-dimensional method based on intraoral scan and apply it to evaluation of the facial soft tissue contour alterations following single immediate implant and immediate provisionalization (IIPP) in central incisor via intraoral scanning. Methods: This study was a prospective clinical study. The trial was conducted at Department of Implantology, Peking University School and Hospital of Stomatology, from January 2016 to September 2017. Twenty-nine eligible consecutive patients (15 women, 14 men) with a mean age of (34.3±12.0) were included and received immediate replacement of the failure maxillary single central incisor. A screw-retained immediate restoration was delivered for each patient. At 6-month follow-up, impression was taken and a screw-retained permanent restoration was performed for each patient. The anterior maxillary region was scanned by an intraoral scanning system at pre-surgery and 1-year follow-up. The Standard Tessellation Language (STL) files were output to a dedicated software and superimposed. Mid-facial recession and gingival zenith symmetry at 1-year follow-up were measured in the digital models. Three-dimensional configurations of the contour change volume were calculated and reconstructed for visual analysis. Furthermore, the following parameters were used to analyze the reconstructed volume: mean contour change in thickness (△d), mesio-distal width (D(W)), coronal-apical height (D(H)), contour change at 0, 1, 2, 3, 4, 5 mm apical to the free gingival margin on the implant site. Results: Twenty-seven out of twenty-nine enrolled patients were finally available for analysis. At 1-year follow-up, the mid-facial mucosa level at implant site was (0.23±0.39) mm apical to the gingival zenith of the contralateral tooth. In general, a contour collapse was found in every patient. △d, D(W) and D(H) of the collapsed volume were (0.62±0.22), (11.03±1.74) and (6.82±1.52) mm, respectively. Contour change at 0, 1, 2, 3, 4, 5 mm apical to the free gingival margin on the implant site were (0.54±0.48), (0.87±0.62), (1.03±0.46), (0.96±0.52), (0.90±0.52), (0.89±0.57) mm. Conclusions: The described quantitative measurement based on intraoral scan can be an effective method for assessment of soft tissue contour changes. At 1 year following single IIPP treatment in maxillary incisor, free gingival margin is stable, with only mild recession. The mean level of the facial soft tissue contour collapse is 0.62 mm.


Assuntos
Implantes Dentários para Um Único Dente , Imagem Tridimensional , Carga Imediata em Implante Dentário , Incisivo , Estética Dentária , Feminino , Humanos , Masculino , Maxila , Estudos Prospectivos , Resultado do Tratamento
9.
Zhonghua Gan Zang Bing Za Zhi ; 25(4): 263-267, 2017 Apr 20.
Artigo em Chinês | MEDLINE | ID: mdl-28494544

RESUMO

Objective: To investigate the expression of programmed death-1 (PD-1) in liver tissue and its association with liver pathology in patients with autoimmune hepatitis (AIH). Methods: A total of 54 AIH patients (38 in the active stage and 16 in the remission stage) were enrolled, and 9 healthy volunteers were enrolled as control group. Immunohistochemistry combined with quantitative image analysis was used to measure the expression of PD-1 in liver tissue. The t-test, rank sum test, one-way analysis of variance, least significant difference t-test, Mann-Whitney U test, and Pearson relation analysis were used for statistical analysis of different types of data. Results: The AIH group had a significantly higher positive rate of PD-1 in liver tissue than the control group (13.57%±6.84% vs 2.22%±0.66%, P < 0.01), and the patients in the active stage of AIH had a significantly higher positive rate of PD-1 in liver tissue than those in the remission stage (16.53%±7.72% vs 6.56%±3.16%, P < 0.01). The positive rate of PD-1 in liver tissue was 6.56%±3.16% in G0 group, 14.33%±5.08% in G1-2 group, and 19.23%±5.41% in G3-4 group (P < 0.01), but there was no significant difference in the positive rate of PD-1 between S0, S1-2, and S3-4 groups (P > 0.05). In AIH patients, the positive rate of PD-1 in liver tissue was positively correlated with the levels of total bilirubin, alanine aminotransferase, aspartate aminotransferase, and IgG (r = 0.665, 0.721, 0.711, and 0.813, all P < 0.01). Conclusion: AIH patients have regulated PD-1 expression in liver tissue, which is closely associated with liver inflammation and is not associated with fibrosis degree, suggesting that PD-1 is involved in the development and progression of inflammation in AIH patients.


Assuntos
Aspartato Aminotransferases/sangue , Hepatite Autoimune/metabolismo , Inflamação/imunologia , Receptor de Morte Celular Programada 1/imunologia , Alanina Transaminase , Estudos de Casos e Controles , Hepatite Autoimune/diagnóstico , Humanos , Receptor de Morte Celular Programada 1/fisiologia
10.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 52(1): 3-9, 2017 Jan 09.
Artigo em Chinês | MEDLINE | ID: mdl-28072987

RESUMO

Objective: To evaluate the primary clinical outcomes of immediate provisionalization with a monolithic crown utilizing a novel chairside computer aided design and computer aided manufacture (CAD/CAM) workflow for single tooth immediate implant placement. Methods: This pilot study was a prospective within-subjects design. Thirteen consecutive patients were included and diagnosed with untreatable single incisor or premolar with fine general and local anatomical conditions. The trial was conducted at Department of Implantology, Peking University School and Hospital of Stomatology, Beijing, between January 2016 and June 2016. The teeth were extracted atraumatically and implants were immediately placed in the fresh sockets. Two screw-retained interim crowns were fabricated for the same site utilizing different workflows, a monolithic lithium disilicate (LS2) crown produced by CEREC (Sirona, Germany) chairside CAD/CAM system (CER group) and a manually fabricated resin crown utilizing conventional workflow (CONV group) respectively. The patients were blinded to the group allocation of the two interim crowns. After the clinical try-in for both crowns in a randomized sequence, the patients' level of satisfaction was assessed with a virtual analogue scale (VAS) questionnaire. The restorations chosen by patients themselves were seated in the implants by one experienced prosthodontist. The accuracy, aesthetic effect and clinical time consumption of both groups were compared. Statistical analyses were performed with the Wilcoxon signed rank test. Results: All patients were treated with atraumatic tooth extraction, immediate implant placement using flapless surgery and immediate provisionalization in a single visit. The interim crowns of both groups could be fitted with or without slight adjustments. For each patient, the interim crown of CER group was chosen to be seated with a relatively higher VAS result. The white esthetic score (WES) results demonstrated no statistically significant difference between CER group (7.5±1.1) and CONV group (7.9±0.9) (P>0.05). The mean total work time was significantly different resulting in (131.9±5.0) min for CER group and (205.2±6.3) min(P<0.05). The major difference lied in the laboratory work time, resulting in (113.5±6.3) min for CER group which was significantly shorter than (185.6±6.6) min for CONV group. As for impression taking time, the CER group (7.5±0.8) min was significantly shorter than CONV group (11.7± 1.1) min (P<0.05). However, analysis for clinical adjustment time showed a significantly longer time for CER group [(11.0±2.1) min vs (8.0±2.8) min, P<0.05]. After 3-6 months of observation, the overall survival rate was 100%. Screw loosening occurred in 4 patients and was tightened again. No other major complication soccurred. Conclusions: The full digital workflow utilizing CEREC chairside CAD/CAM system to fabricate interim crowns after immediate implant placement in one single visit was feasible. It was more time-efficient and could effectively shorten the laboratory work time compared to the conventional workflow. Patients demonstrated high satisfaction and there was no statistical difference in WES results compared to the conventional workflow. Favorable clinical outcomes were gained in this short-term follow-up study.


Assuntos
Projeto Auxiliado por Computador , Coroas , Implantes Dentários para Um Único Dente , Cerâmica , Porcelana Dentária , Seguimentos , Humanos , Projetos Piloto , Estudos Prospectivos , Distribuição Aleatória , Extração Dentária , Resultado do Tratamento
11.
Epidemiol Infect ; 143(13): 2822-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25648505

RESUMO

HBV genotypes have specific geographical distributions and can serve as epidemiological markers. Accumulated data have shown that the major HBV genotypes in China are B and C. Here, the HBV genotypes were examined from 6817 blood samples, which were collected from patients with chronic HBV infection in Fujian Province during 2006-2013; genotype B was identified in 3384 patients (49·6%), while genotype C was identified in 3430 patients (50·3%). The percentage of patients infected with genotype C gradually increased with age from 39·5% (patients aged 50 years), reaching a peak of 67·3% in the 45-50 years age group. These results clearly demonstrate that the genotype distribution of HBV in Fujian Province has significantly changed in recent years with almost equal numbers of genotype B and genotype C infections existing in the entire patient population, while higher incidence of genotype C infection exists in older patients, but genotype B is no longer dominant in the Fujian area as previously reported.


Assuntos
Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Adolescente , Adulto , China/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
12.
J Phys Chem Lett ; 4(2): 310-6, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-26283440

RESUMO

To realize the origin of efficient spin injection at organic-ferromagnetic contact in organic spintronics, we have implemented the formation of quasi-molecular magnet via surface restructuring of a strong organic acceptor, tetrafluoro-tetracyano-quinodimethane (F4-TCNQ), in contact with ferromagnetic cobalt. Our results demonstrate a spin-polarized F4-TCNQ layer and a remarkably enhanced magnetic anisotropy of the Co film. The novel magnetic properties are contributed from strong magnetic coupling caused by the molecular restructuring that displays an angular anchoring conformation of CN and upwardly protruding fluorine atoms. We conclude that the π bonds of CN, instead of the lone-pair electrons of N atoms, contribute to the hybridization-induced magnetic coupling between CN and Co and generate a superior magnetic order on the surface.

13.
Phys Rev Lett ; 109(15): 156602, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23102348

RESUMO

We demonstrate that a giant spin Hall effect (SHE) can be induced by introducing a small amount of Bi impurities in Cu. Our analysis, based on a new three-dimensional finite element treatment of spin transport, shows that the sign of the SHE induced by the Bi impurities is negative and its spin Hall (SH) angle amounts to -0.24. Such a negative large SH angle in CuBi alloys can be explained by applying the resonant scattering model proposed by Fert and Levy [Phys. Rev. Lett. 106, 157208 (2011)] to 6p impurities.

14.
Nat Commun ; 3: 1058, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22968704

RESUMO

The spin Hall effect and its inverse have key roles in spintronic devices as they allow conversion of charge currents to and from spin currents. The conversion efficiency strongly depends on material details, such as the electronic band structure and the nature of impurities. Here we show an anomaly in the inverse spin Hall effect in weak ferromagnetic NiPd alloys near their Curie temperatures with a shape independent of material details, such as Ni concentrations. By extending Kondo's model for the anomalous Hall effect, we explain the observed anomaly as originating from the second-order nonlinear spin fluctuation of Ni moments. This brings to light an essential symmetry difference between the spin Hall effect and the anomalous Hall effect, which reflects the first-order nonlinear fluctuations of local moments. Our finding opens up a new application of the spin Hall effect, by which a minuscule magnetic moment can be detected.

15.
J Nanosci Nanotechnol ; 11(3): 2593-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21449433

RESUMO

Thermal process effect on the microstructure and magnetic characterizations of epitaxial FePd multilayer films grown on MgO(001) substrates via electron-beam deposition have been investigated. For the FePd films directly grown at 400 degrees C, the isolated island-like morphology was observed and displayed a perpendicular magnetic anisotropy with a large coercivity of 8000 Oe. On the other hand, the FePd films grown at 100 degrees C and then post-annealed at 400 degrees C showed continuous film morphology and with a lower remanence corresponded to the alternate up and down orientations of the magnetization. The significant distinction in magnetic exhibition of the FePd films was due to the remarkable change in surface and magnetic domain structures caused by varied interfacial energy during different thermal processes.


Assuntos
Ferro/química , Óxido de Magnésio/química , Magnetismo , Membranas Artificiais , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Paládio/química , Cristalização/métodos , Temperatura Alta , Teste de Materiais , Tamanho da Partícula
16.
J Nanosci Nanotechnol ; 11(3): 2598-602, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21449434

RESUMO

Monodispersed FePt nanoparticles with hydrophobic ligand were chemically synthesized and with controllable surface-functional properties. In order to enhance the saturation magnetization of FePt nanoparticles, the initial mole ratio of Fe to Pt precursors and reaction times were controlled to effectively increase magnetization due to the increased particle size and formation of FePt-Fe3O4 nanocomposites. The surface modification of FePt nanoparticles by using mercaptoacetic acid (C2H4O2S) as a phase transfer reagent through ligand exchange turned the nanoparticles hydrophilic, and the nanoparticles could water-dispersible. The streptavidin-biotin binding pair was used to conjugate with carboxylic acid (COOH) functional group on the surface of FePt nanoparticles that could be further functionalized to provide a biotin moiety for specific interactions with streptavidin protein.


Assuntos
Cristalização/métodos , Ferro/química , Magnetismo , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Platina/química , Estreptavidina/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Ligação Proteica , Propriedades de Superfície
17.
Phys Rev Lett ; 106(12): 126601, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21517335

RESUMO

We study the extrinsic spin Hall effect induced by Ir impurities in Cu by injecting a pure spin current into a CuIr wire from a lateral spin valve structure. While no spin Hall effect is observed without Ir impurity, the spin Hall resistivity of CuIr increases linearly with the impurity concentration. The spin Hall angle of CuIr, (2.1±0.6)% throughout the concentration range between 1% and 12%, is practically independent of temperature. These results represent a clear example of predominant skew scattering extrinsic contribution to the spin Hall effect in a nonmagnetic alloy.

18.
J Nanosci Nanotechnol ; 10(7): 4581-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21128460

RESUMO

Periodic Ag line arrays with different line pitches from 500 nm to 950 nm on ITO coated glass substrates have been fabricated by using electron-beam lithography (EBL) technique for studying the color light guide in a display system. The patterned Ag line array is used as a light outcoupling and color-selection component due to the emission wavelength changed by the Ag line arrays with different periodic distances that could achieve color variation. We have demonstrated that the ITO coated glass substrates containing periodic Ag line arrays with varied line pitches can be used as a color filter in a display device. This means that with a proper metallic nanostructure layer, the red, green, and blue colors in a display system can be obtained without a traditional color filter for modern multi-applications of optoelectronic display devices.

19.
Phys Rev Lett ; 104(17): 177204, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20482136

RESUMO

To emulate the interfacial regimes of a Co/Pc/Co spin-valve structure, we fabricated ultrathin pentacene/cobalt (Pc/Co) and cobalt/pentacene (Co/Pc) bilayers. Through measurement of the magneto-optical Kerr effect, we found the Co layer has its magnetic properties depend strongly upon the order of deposition. Further x-ray spectroscopy and microscopy investigation indicated Co/Pc was chemically stable, whereas Pc/Co was reactive and exhibited complex magnetization pattern. The different chemistry and magnetic configurations at interfaces could cause additional complication for spin injection.

20.
Phys Rev Lett ; 103(22): 225504, 2009 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-20366107

RESUMO

Submonolayer deposition of 3d transition metals such as Cr, Mn, Fe, Co, and Ni on Pd(110) at room temperature causes the formation of monoatomic chains of Pd as identified with scanning tunneling microscopy and spectroscopy. In agreement with recent theoretical predictions [Phys. Rev. B 79, 155410 (2009)], the substitution of Pd substrate atoms with the deposited atoms of 3d metals is found to be responsible for the formation of Pd atomic chains. This finding clarifies the long-debated issue about the chemical composition of the atomic chains grown on Pd(110) and points out the intriguing processes in the formation of self-assembled and self-organized nanostructures.

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