Thickness-Dependent Polar Domain Evolution in Strained, Ultrathin PbTiO3 Films.

Ferroelectric ultrathin films have great potential in electronic devices and device miniaturization with the innovation of technology. In the process of product commercialization, understanding the domain evolution and topological properties of ferroelectrics is a prerequisite for high-density storage devices. In this work, a series of ultrathin PbTiO3 (PTO) films with varying thicknesses were deposited on cubic KTaO3 substrates by pulsed laser deposition and were researched by Cs-corrected scanning transmission electron microscopy (STEM), reciprocal space mapping (RSM), and piezoresponse force microscopy (PFM). RSM experiments indicate the existence of a/c domains and show that the lattice constant varies continuously, which is further confirmed by atomic-scale STEM imaging. Diffraction contrast analysis clarifies that with the decrease in PTO film thickness, the critical thickness for the formation of a/c domains could be missing. When the thickness of PTO films is less than 6 nm, the domain configurations in the ultrathin PTO films are the coexistence of a/c domains and bowl-like topological structures, where the latter ones were identified as convergent and divergent types of meron. In addition, abundant 90° charged domain walls in these ultrathin PTO films were identified. PFM studies reveal clear ferroelectric properties for these ultrathin PTO films. These results may shed light on further understanding the domain evolution and topological properties in ultrathin ferroelectric PTO films.

[Structure validity of an occupational commitment scale for traditional Chinese medical practitioners].

OBJECTIVE: To test the structure validity of an occupational commitment scale for traditional Chinese medical (TCM) practitioners. METHODS: Based on in-depth interviews with 18 TCM practitioners and an open-ended questionnaire survey of 67 TCM practitioners, an occupational commitment scale was developed. The questionnaire was tested in 324 TCM practitioners and revised after an exploratory factor analysis (EFA). The revised questionnaire was tested again in another 507 TCM practitioners. A measurement model (structural equation model) by confirmation factor analysis (CFA) was used to confirm the construct validity of the questionnaire. The occupational change intention was used to verify the criterion-related validity of the questionnaire. The reliability of the questionnaire was tested with Cronbach's alpha coefficient. RESULTS: The EFA indicated that the occupational commitment scale consisted of four components from 13 items. The cumulative contribution of the four components reached 61.437%. The factor loading of each item attached to the relevant common factor ranged from 0.591 to 0.861. The CFA indicated a good fit of construct, with 1.79, 0.039, 0.97, 0.97, 0.98, and 0.72 fit index for chi2/ df, RMSEA, GFI, NNFI, CFI, and PNFI respectively. The occupational change intention correlated with the componets of occupational commitment negatively (P < 0.01). The Cronbach's alpha coefficients of the questionnaire and the four components ranged from 0.602 to 0.847. CONCLUSION: The occupational commitment scale for TCM practitioners has a valid structure of four dimensions, measuring affective commitment, limited alternatives commitment, professional self-efficacy commitment and occupational risk commitment. The questionnaire is valid and reliable.

[Effect of occupational commitment on job burnout of traditional Chinese medicine doctors].

OBJECTIVE: To investigate the status of job burnout in traditional Chinese medicine (TCM) doctors and explore the effect of occupational commitment on job burnout. METHODS: A test of occupational commitment and job burnout was carried out in 507 TCM doctors with occupational commitment questionnaire and Maslach Burnout Inventory-Human Services Survey (MBI-HSS). RESULTS: The age group of < 30 years scored lowest (2.352 +/- 0.660) in personal accomplishment compared with 30 years old group and 40 years old group [(2.136 +/- 0.704) and (2.127 +/- 0.628) respectively] (P < 0.01). The score of emotional exhaustion and depersonalization increased with educational levels. There was significantly negative correlation between job burnout and occupational commitment (P < 0.01). Occupational commitment had significant effect on job burnout (P < 0.01). Occupational trouble commitment was a major predictor for emotional exhaustion (P < 0.01). Professional self-efficacy commitment was a major predictor for depersonalization (P < 0.01). Affective commitment was a major predictor for personal accomplishment (P < 0.01). CONCLUSION: Occupational commitment is a good predictor for job burnout. Improving occupational commitment is an important measure to prevent job burnout.

Association between interleukin-10-3575T>A (rs1800890) polymorphism and cancer risk.

BACKGROUND: Previous studies investigated the associations of interleukin-10 (IL-10) polymorphisms with different types of cancer, indicating an influence on cancer risk. IL-10-3575T>A (rs1800890) has been studied concerning a potential implication in terms of some cancer site risks, but the results from single studies are contradictory. METHODS: Eligible articles were identified by a search of the PubMed, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) databases until November 30, 2014. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the cancer risk by cancer sites, ethnicity, and other study features. RESULTS: We identified 15 published studies to research the link of the IL-10-3575T>A polymorphism with cancer risk. Our meta-analysis indicated that the IL-10-3575T>A polymorphism has a significant association with decreased melanoma risk in the heterozygote model (OR=0.67, 95% CI=0.49-0.92, p=0.02) and dominant model (OR=0.70, 95% CI=0.52-0.95, p=0.01), but increased diffuse large B-cell lymphoma (DLBCL) risk in all the different genetic models. CONCLUSION: Our analysis suggests that the IL-10-3575T>A mutation may associate with melanoma and DLBCL and exert a differential effect in different cancer sites. However, other factors may influence the association, and large-scale multicenter with adequate methodological quality studies are needed to confirm the impact on cancer susceptibility.

[Association between the functional monoamine oxidase A gene polymorphism and aggressively driving behavior].

OBJECTIVE: This study is purposed to explore the relationship between aggressively driving behavior and functional polymorphism in the promoter region of the monoamine oxidase-A (MAOA) gene. METHODS: A total of 348 automobile drivers were investigated with Deffenbacher's driver anger scale, driving vengeance questionnaire (DVQ) and driver aggression behavior questionnaire. Eighty-eight drivers were selected as more, medium and less aggressive group, each. Polymerase chain reaction (PCR) and 2.5% agarose gel electrophoresisi were adopted to detect the polymorphism of functional 30 bp-uVNTR in the promoter region of the X-chromosomal MAOA gene and their frequencies of varied genotypes were estimated. RESULTS: Two alleles with 3 and 4 repeats of 30 bp-uVNTR were detected in the drivers. Among the more aggressive group, number of the allele with 3 repeats of 30 bp-uVNTR (63/88) was significantly more than that with 4 repeats (25/88) (chi(2) = 10.21, P < 0.01), and number of the allele with 4 repeats of 30 bp-uVNTR was more in the less aggressive group, indicating that persons with allele of 3 repeats of 30 bp VNTR were more aggressive in their driving than those with 4 repeats. CONCLUSIONS: Aggressively driving behavior in drivers possibly related to their functional MAOA-uVNTR polymorphism. Effect of the gene on aggressively driving behavior should be further studied.

[Human factors of drivers and traffic accidents].

OBJECTIVE: To find out the relationship of traffic accidents with life events, driving stress, aggressive driving, etc. METHODS: A total of 905 automobile drivers were investigated with life events scale (LES), general driver stress questionnaire, driver behavior inventory and accidents experience, etc. RESULTS: The scores of life events, driving stress, and aggressive driving in accident drivers (21.79 +/- 14.10, 23.81 +/- 11.86, 9.42 +/- 8.25 respectively) were higher than those in nonaccident drivers (16.82 +/- 8.45, 20.09 +/- 10.63, 5.66 +/- 7.54) (P < 0.01). The number of vehicle accidents was significantly correlated with the scores of LES, driving stress, driver's aggressive behavior, drowsy driving, weekly time of driving, drinking index (P < 0.05). A logistic analysis (Forward:LR) showed that the driving hour, drowsy driving, aggressive driving, and drinking index were closely related with traffic accidents (P < 0.01). CONCLUSION: Life events, driving stress and aggressive driving of the drivers are important factors related to traffic accidents.