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Background With the aging of the population, the prevalence of atrial fibrillation is increasing year by year. As the "gatekeepers" of community residents' health, grassroots medical staff with a high level of knowledge about atrial fibrillation is particularly important for standardized management of atrial fibrillation. Objective To analyze the mastery of atrial fibrillation-related knowledge among grassroots medical staff in Fengxian District, Shanghai and its influencing factors, thus, providing a theoretical basis for subsequent training work. Methods This study is a cross-sectional survey study. From June to July 2021, a systematic sampling method was used to select 1 393 grassroots medical staff as the research objects including general practitioners, nurses, pharmacists, public health physicians and other medical staff (imaging technology/physician, laboratory technician, traditional Chinese medicine doctor and so on) from 21 community health service centers in Fengxian District, Shanghai. This study used a self-developed electronic questionnaire to investigate them. The contents of the questionnaire included general information and knowledge related to atrial fibrillation (basic knowledge about atrial fibrillation, knowledge about anticoagulant therapy and knowledge about rhythm/heart rate control) . This study compared the mastery of atrial fibrillation-related knowledge among grassroots medical staff in different positions, and used univariate Logistic regression, ordinal multiple classification or binary Logistic regression to analyze the influencing factors of grassroots medical staff's mastery of atrial fibrillation-related knowledge. Results A total of 1 383 valid questionnaires were recovered, and the valid questionnaire recovery rate was 99.28%. Among 1 383 grassroots medical staff, 506 cases (36.59%) were general practitioners. 54.88% (759/1 383) , 97.69% (1 351/1 383) and 69.63% (963/1 383) failed in the basic knowledge about atrial fibrillation, knowledge about anticoagulation and knowledge about heart rhythm/heart rate control, respectively. There were statistically significant differences in the scores of atrial fibrillation knowledge, anticoagulation knowledge and heart rhythm/heart rate control knowledge among grassroots medical staff in different positions (P

From the Institute of Scientific Information (ISI) Eigenfactor Project 2015 category, 115 journals in six disciplines which are ranked top 20 in order of impact scores in their own disciplines were selected. A total of 1002 industrial cluster research studies collected from the Web of Science between 1998 to 2019 were used as samples. BibExcel software was used for data cleaning and literature co-citation analysis, and co-occurrence matrix was inserted into SPSS software and Pajek software for exploratory factor analysis and network analysis, respectively. The differences and commonalities of the two results obtained from exploratory factor analysis and network analysis were compared by reading literature abstracts and manuscripts to robustly identify the knowledge base. According to the framework of 2W1H, the knowledge module was integrated into a problem-oriented system to understand the internal logic mechanism of the entire study. The top 41 studies in the citation frequency of each period from 1998 to 2005, 2006 to 2012, and 2013 to 2019 were selected to analyze the keyword co-occurrence in different periods, main theoretical basis, contextual focus, evolution of research topics, and important research trends. The results show that: 1) The knowledge base of industrial clusters can be divided into nine modules: external economics and new economic geography, new industrial district theory, competitive advantage theory, evolutionary economic geography, buzz and pipelines, regional innovation system, new economic sociology, absorptive capacity, and global chains; 2) The knowledge structure of these modules can be reflected through the 2W1H research framework, in which the WHAT part is composed of four modules: external economics, new economic geography, new industrial district theory, competitive advantage theory, and evolutionary economic geography. It answers the questions regarding concept, types and development stages of the cluster. The knowledge base of cluster type research in this part is less, which reflects the lack of corresponding research literature, and therefore this needs to be enriched using typology theory. The part WHY is composed of external economics and this is divided into two modules, i.e., new economic geography and competitive advantage theory, which answer the questions about the causes of cluster and its impact on regional or enterprise competitive advantage. In the 21st century, researchers have paid increasing attention to the causes of urban cultural and creative industry cluster formation. The part HOW is composed of five modules: buzz and pipelines, regional innovation system, new economic sociology, absorptive capacity, and global chains. This part is the most important, and can be categorized into three levels: enterprise, region, and country; 3) Between 1998-2019, the regional innovation system had been the main theoretical source of cluster. Evolutionary economic geography had occupied a significant position between 2006 and 2012 and it tended to blend with the global chain. The important theoretical sources of the three periods were constantly updated and enriched, thereby increasing the degree of integration with management theory. The focused industries of the three periods were more diverse, especially the status of the service industry, and the focus regions were later transferred to emerging markets and underdeveloped markets; innovation and local economic development had always been the core topics of the three periods. From 2006 to 2012, globalization and entrepreneurial activities received more attention. From 2013 to 2019, management theory occupied the main position, as it focused on new topics such as environmental governance and stakeholder management, and paid more attention to social, ecological, and other issues. Finally, based on the results, some suggestions for domestic research were presented.

To evaluate the effect of poly(methyl) siloxane(PMSQ) on the mechanical and physicochemical properties of PHB/PCL films, 2 wt % PMSQ was added to the polyhydroxybutyrate(PHB) /polycaprolactone(PCL) blending systems with mass ratios of 25:75, 50:50, 75:25 to prepare films by solution casting method. The results indicated that PMSQ exhibited an optimal enhancing effect on the tensile performance of the PHB25/PCL75 blends, resulting in an increase in elongation at break from 22.45 % to 70.83 %. FTIR spectra demonstrated the disappearance of the methyl (-CH3) absorption peak of PMSQ along with an enhancement in the absorption peak intensity of the C=O bond in the PHB/PCL blending system. These results indicated that PHB and PCL were grafted onto PMSQ microspheres. SEM observation showed that the addition of PMSQ reduced the particle size of the PHB and PCL domains. The phase separation between the PHB and PCL phases was depressed due to an enhancement in their compatibility. DSC analysis suggested that the addition of PMSQ restricted the motion of PHB and PCL molecular chains and disrupted their spatial regularity, thus resulting in a decrease in crystallinity. In addition, TGA analysis indicated the addition of PMSQ increased the onset degradation temperature of the PHB/PCL blending systems and enhanced their thermal stability in accordance with the mass ratio of the two components. [ABSTRACT FROM AUTHOR]

In order to optimize the coil design of high power resonant wireless power transmission (WPT) system and improve its transmission efficiency, an equivalent circuit model of two-coil series-series topology with current source is analyzed, from which four factors to optimize the coil design are proposed, i. e. more coil turns, bigger coil average radius, shorter transmission distance and suitable load and it is simulation verified using the COMSOL software. Moreover, two magnetic field distribution diagrams of both transmitting and receiving coils during each resonance are obtained using COMSOL. Therefore, complete and intuitive optimization of coils design of the resonant WPT system can be achieved, and thus high efficiency transmission of the high power resonant WPT system can be realized. The results show that the coils can be optimized by increasing the number of coil turns, increasing the average radius of the coils, reducing the transmission distance and selecting the proper load, at the same time, considering reducing the difference between the inner and outer diameters of the planar circular coils as much as possible, so as to enhance the transmission efficiency of the resonant WPT system. [ABSTRACT FROM AUTHOR]

Objective: To investigate the impairment of lead exposure on rat hypothalamus and striatum., Methods: Forty-five healthy SPF male SD rats were randomly divided into three groups, control group( double distilled water), low( 60 mg/kg BW) and high dose( 120 mg/kg BW) groups. The rats were treated with lead acelate water solution in lead exposure group by gavage for 9 weeks. Open-field test was used to detect behavioral changes of the rats. The lead content of hypothalamus and striatum was determined by inductively coupled plasma mass spectrometry( ICP-MS). The mRNA expressions of toll-like receptor 4( TLR4), nuclear transcription factor kappa B( NF-κB), tumor necrosis factors alpha( TNF-α), interleukin-1( IL-1β) and 8-oxoguanine DNA glycosylase( OGG1) were measured by real-time PCR. Enzyme linked immunosorbent assay( ELISA) was applied to detect the protein content of TLR4, NF-κB, TNF-α, IL-1β and 8-hydroxy-2-deoxyguanosine( 8-OHd G)., Results: There were no significant differences in terms of body weight among three groups of rats. Compared with the control group, total movement distance, the total number of lattice and the distance of the central region in low and high lead exposure group were significantly decreased( P < 0. 05). The lead contents in hypothalamus and striatum of rats of low and high lead exposure group were( 60. 10 ± 6. 71), ( 71. 20 ± 11. 24), ( 44. 07 ± 9. 63)and( 66. 67 ± 8. 78) μg/g, respectively, higher than those in the control group(( 33. 77± 8. 19), ( 25. 75 ± 6. 33) μg/g)( P < 0. 05). While compared with the control group, the mRNA expression of NF-κB and OGG1 of the low and high lead exposure group were( 3. 47 ± 0. 15), ( 1. 43 ± 0. 16) and( 0. 67 ± 0. 13), ( 0. 57 ± 0. 19) folds in hypothalamus, there were marked differences in the mRNA expression of TLR4 and NF-κB between low and high lead group. The NF-κB, TNF-α, IL-1β protein contents in hypothalamus of the low lead exposure group were( 5. 85 ± 1. 10), ( 56. 15 ± 6. 96) and( 1. 18 ± 0. 20) ng/g, respectively higher than those in control group(( 3. 03 ± 0. 71), ( 49. 25 ± 7. 21) and( 0. 86 ± 0. 11) ng/g)( P < 0. 05). The TLR4, NF-κB, TNF-α, IL-1β protein contents in hypothalamus of the high lead exposure group were( 0. 67 ± 0. 12), ( 4. 74 ± 0. 68), ( 69. 73 ± 9. 61) and( 1. 43 ± 0. 29) ng/g, respectively, higher than those in control group. There were marked differences in the protein contents of TLR4 and TNF-α significant between low and high lead group in hypothalamus. The mRNA expression of TLR4, NF-κB, IL-1β in the striatum of rats in the high lead exposure group were significantly higher than those in control group( P < 0. 05). The TLR4, NF-κB, TNF-α, IL-1β, 8-OHd G protein contents of the high lead exposure group were( 0. 33 ±0. 02) ng/g, ( 4. 66 ± 0. 51), ( 82. 63 ± 7. 99), ( 1. 92 ± 0. 35) and( 1. 21 ± 0. 14) ng/g, respectively higher than those in control group( P < 0. 05), NF-κB protein content of the high lead exposure group was higher than that in low lead exposure group( P < 0. 05)., Conclusion: Lead exposure does result in the impairment of hypothalamus and striatum, indicating that inflammation and oxidative damage might be involved in this process.

Objective: To investigate the impact of NU7026 and Wortmannin, inhibitors of DNA-dependent protein kinase (DNA-PK), in HL60 cells apoptosis induced by 1, 4-benzoquinone (1, 4-BQ)., Methods: HL60 cells were divided into three groups according to the exposures: the poisoned groups which were treated with 0, 5, 10, 25 and 50 µmol/L 1, 4-BQ for 24 h, respectively, the NU7026 groups which were preincubated with 10 µmol/L NU7026 for 1h prior to the 24h treatment of 0, 5, 10, 25 and 50 µmol/L 1, 4-BQ and the Wortmannin groups which were preincubated with 25 µmol/L Wortmannin for 1h prior to the 24 h treatment of 0, 5, 10, 25 and 50 µmol/L 1, 4-BQ. Then we detected the apoptosis via flowcytometry Annexin V-FITC/PI and the DNA Ladder, respectively. We also tested the expressions of Bax mRNA with Real-Time PCR in HL60 cells which were exposed to 10 µmol/L NU7026 for 24 h, 25 µmol/L Wortmannin 24 h, 10 µmol/L 1, 4-BQ 24 h, 10 µmol/L NU7026 1h+10 µmol/L 1, 4-BQ 24 h and 25 µmol/L Wortmannin 1 h+10 µmol/L 1, 4-BQ 24 h, as well as null (control). We also examed the expressions of p53 in HL60 cells with Western blot., Results: Annexin V-FITC/PI apoptosis tests suggested that apoptosis rates of NU7026+10 µmol/L 1, 4-BQ group and Wortmannin +10 µmol/L 1, 4-BQ were 17.6±1.19% and 15.2±1.22%, respectively. Both of results were higher than that of 10 µmol/L 1, 4-BQ group (6.3±1.04%); Apoptosis of NU7026+25 µmol/L 1, 4-BQ group was 46.2±3.55%, and Wortmannin +25 µmol/L 1, 4-BQ group 26.9±2.62%. Both of results were also higher than that of 25 µmol/L 1, 4-BQ group (14.1±1.54%); Apoptosis of NU7026+50 µmol/L 1, 4-BQ group (61.8±1.78%) was higher than that of 50 µmol/L 1, 4-BQ group (35.9±4.51%). The above results were all statistically significant (P < 0.05)., Results: of DNA-Ladder were basically consistent with those of Annexin V-FITC/PI apoptosis tests. In addition, both NU7026 and Wortmannin pretreatment elicited the higher expression of Bax mRNA in HL60 treated by 1, 4-benzoquinone with statistically significance (P < 0.05). However, p53 protein was not detected in HL60 cells as the western blot indicated., Conclusion: Inhibitors of DNA-PK, NU7026 and Wortmannin, promote p53-independent apoptosis induced by 1, 4-benzoquinone in HL60 cells.

Objective: To investigate the effects of antidepressant citalopram on the gene expressions of tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL-1β), and to discuss the impacts of citalopram on p38 and c-jun N-terminal kinase (JNK) of mitogen-activated protein kinase (MAPK) family in microglial cells., Methods: BV2 cells were induced by lipopolysaccharide (LPS) to produce TNF-α and IL-1β. After pretreatment with citalopram (20 μmol/L) for 4 h, the mRNA levels of TNF-α and IL-1β were measured by quantitative real-time PCR (qRT-PCR); after pretreatment for 24 h, the protein levels of TNF-α and IL-1β were analyzed by ELISA; the effects of citalopram on the phosphorylation of p38MAPK and JNK were observed after pretreatment for 30 min., Results: Citalopram significantly inhibited the mRNA and protein expressions of TNF-α and IL-1β, and the phosphorylation of p38MAPK and JNK., Conclusion: Citalopram may play the anti-inflammatory role by inhibiting MAPK pathway in microglial cells.