Objective: To develop a suitable scale for assessing the public health safety literacy in residents in China. Methods: The initial scale of Chinese public health safety literacy was developed through theoretical conceptualization, item pooling, field verifying and item inclusion and exclusion. Then the initial scale was converted into an electronic questionnaire. A total of 2 809 residents from 4 provinces were randomly selected for field testing. Classical test theory (CTT) and item response theory (IRT) were used for item reduction. SPSS 23.0 was used for exploratory factor analysis (EFA) and unidimensional testing. Package R 4.1.1 ltm and mirt were used for the analysis of the psychometric properties of items and generate the ICC, IIC and TIF. Results: The initial scale had 30 items (B1-B30), and the test took 9.8 s to complete one item averagely. According to the CTT, B2 was deleted due to coefficient of total correlation (CITC) <0.3 and the item-dimension correlation coefficient (IDCC) <0.4. B23 was deleted due to CITC<0.3, IDCC<0.4 and difficulty index (W) <0.2. B30 was deleted due to CITC<0.3 and W<0.2. The total Cronbach's α of the scale was 0.923 after deletion. EFA indicated that 14 items should be deleted due to lower factor loadings <0.7. EFA was conducted for remaining 13 items and 2 common factors were extracted, the factor loadings of all items were >0.7, the accumulated variance contribution of the 2 common factors was 63.361%, and the total Cronbach's α was 0.891, showing unidimensionality, IRT was used to test the remaining items. B14 and B20 were deleted due to discrimination coefficient (a) <0.3, difficulty threshold coefficient (b) ∉[-3,3], the small amount of information and the flat, crowded, non-monotonic ICC, and IIC. Finally, the Cronbach's α of the 11-itemed scale was 0.936 with TLI=0.97, CFI=0.99, and RMSEA=0.03. Conclusion: The final scale has good reliability, validity, discrimination, difficulty level and feasibility, and can be applied for the rapid assessment of public health safety literacy in China.

Objective: To develop a measurement scale for the public health and safety literacy of university freshmen. Methods: Item pooling was conducted through literature review and in-depth interview with public health experts, and a nominal group was organized to develop the initial items to form the questionnaire. A total of 250 freshmen were randomly selected to complete the questionnaire, and the assessment of psychometric properties were performed to carry out item reduction by using classical test theory and item response theory. Exploratory factor analysis method (EFA) was employed to calculate the item-factor loadings. The data collected from another 318 freshmen were analyzed using confirmatory factor analysis method (CFA). Results: The scale contained 3 dimensions and 9 items with all content validity index ≥0.8. The difficulty coefficient of 9 items was 1.18-2.43. The discriminative validity analysis showed that the difficulty index was 0.41-0.78, and the discrimination index was 0.38-0.64. Each of the remaining items had a statistically significant difference in the score value between the top 27% and lowest 27% of respondents (t>3, P<0.05). The item's Cronbach's α was 0.72-0.77, corrected item-total correlation was 0.33-0.60 and the overall α of the scale was 0.77. EFA indicated all item-factor loading were higher than 0.680, and the accumulated variance contribution of the 3 factors was 62.484%. Results of CFA showed that the overall fitness index of the model reached the fitness standard except for the χ2 value. There was no statistical significance in the total score of the scale and the scores of each item among groups with different demographic characteristics (P>0.05). Conclusions: The newly developed public health safety literacy scale had a good reliability,validity,stability and item constancy.It can be used in measurement of the public health and safety literacy of university freshmen.

The composite thin films of tin with 0wt.%, 3.2wt.%, 6.0wt.%, and 11.8wt.% graphite on the Cu foil were fabricated by magnetron sputtering (MS). The surface morphology, the composition and the electrochemical performance of the composite films were characterized by scanning electron microscopy (SEM), energy disperse spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and galvanostatic charge/discharge (GC) measurements. It is found that the capacity loss of tin can be significantly reduced by its composite with graphite, but its discharge capacity decreases with increasing the content of graphite. The composite with 6.0wt.% graphite show its good discharge capacity and cyclic stability. Its initial discharge capacity is 750mAhg−1 and it keeps 85% of its initial discharge capacity after 10 cycles, comparing to the 14% for the pure tin.

Spinel lithium manganese oxides (LiMn2O4) modified with and without bismuth by sol–gel method were investigated by theoretical calculation and experimental techniques, including galvanostatic charge/discharge test (GC), cyclic voltammetry (CV), chronopotentiometry (CP), electrochemical impedance spectroscopy (EIS), inductively coupled plasma (ICP), powder X-ray diffraction (XRD), BET measurement, and infrared spectroscopy (IR). It is found that the performance of LiMn2O4 can be improved by the bismuth modification. The modified and the unmodified samples have almost the same initial discharge capacity, 118 and 120mAhg−1, respectively. However, the modified sample has better cyclic stability than the unmodified sample. After 100 cycles, the capacity remains 100 and 89mAhg−1 for the modified and the unmodified samples, respectively. Moreover, the results from EIS show that the modified sample has a quicker kinetic process for Li ion intercalation/de-intercalation than the unmodified one; the charge-transfer resistance of the former is less than one-sixth of that of the latter. After immersion in electrolyte (DMC:EC:EMC=1:1:1, 1molL−1 LiPF6) for 10h at room temperature, the modified sample has less change in open circuit potential, crystal volume, and vibration absorption of Mn–O bond, and has less dissolution of manganese into solution than the unmodified sample.

BACKGROUND:Helicobacter pylori, especially the CagA-positive strains, are closely associated with peptic ulcers and gastric cancers. We performed a large scale gastric cancer screening project and examined the prevalence of H. pylori and CagA-positive strains in Changle, China, an area with one of the World's highest gastric cancer mortality. We also compared the prevalence with that in Hong Kong which has one-tenth of the gastric cancer mortality of that in Changle.METHODS:A total of 2424 subjects in Changle and 523 subjects in Hong Kong had endoscopic examination and venesection. Sera were tested for anti-H. pylori antibody and anti-CagA antibody and correlated with endoscopic findings.RESULTS:In Changle, 80. 9% of the subjects were H. pylori carriers. Out of 551 carriers, 408 (74%) were positive for anti-CagA antibody. A total of 76% and 87% of the asymptomatic and gastric cancer patients were positive for anti-CagA antibody, respectively (P > 0.05). Compared to Hong Kong, there was a significantly (P < 0.0001) higher prevalence of CagA-positive strains in asymptomatic subjects in Changle (76%) than in Hong Kong (28%), but not in peptic ulcers or gastric cancers.CONCLUSIONS:Subjects in Changle had a high prevalence of H. pylori infection and a high prevalence of the CagA-positive strains. The contrast in the prevalence of CagA-positive strains, in asymptomatic subjects in two areas with differing gastric cancer mortality, supports the pathogenic role of CagA-positive strains in gastric carcinogenesis.

Background: Carriers of Helicobacter pylori are believed to have a three‐ to six‐fold increased risk of developing gastric cancer. We have recently conducted a simultaneous cross‐sectional population study on the prevalence of H. pylori infection in a cohort of asymptomatic adult volunteers in two contrasting gastric cancer risk regions of South China, Hong Kong and Changle of Fujian. Their mean annual gastric cancer mortality has been approximately 7.5 and 75/100 000 population, respectively, since the beginning of the last decade. The aim of this study was to evaluate if H. pylori prevalence bears any relationship to gastric cancer mortality rates in these two southern regions of China. Methods: Sera were obtained from 397 volunteers in Hong Kong. They were tested for anti‐H.pylori immunoglobulin (Ig) G antibody by using a commercial enzyme‐linked immunosorbent assay (ELISA) kit. Volunteers of Changle (1456) had upper endoscopy examination and were also tested for anti‐H. pylori IgG antibody by the same ELISA method. Results: The overall H. pylori infection prevalence was significantly higher in Changle (80.4%) than in Hong Kong (58.4%; P < 0.01). The high prevalence is associated with more atrophic gastritis. The overall risk of gastric cancer in people of Changle is approximately five‐fold that of Hong Kong (adjusted odds ratio 4.9, 95% CI 2.5–9.8). Conclusions: It is concluded that the prevalence of H. pylori infection rates bear a direct relationship to gastric cancer mortality rates in these two southern regions of China. Thus, H. pylori most likely plays a significant aetiopathogenetic role in gastric carcinogenesis in subjects living in Changle.

• G1359 AGE IS A PREDICTING FACTOR FOR THE ASSOCIATION BETWEEN CagA POSITIVE HELICOBACTER PYLORI (Hp) INFECTION AND SERUM PEPSINOGEN I:II RATIO IN A HIGH GASTRIC CANCER RISK REGION IN CHINA. BCY Wone. SK Lam, CK Ching, J Ho, ST Yuen, E Kwok, WHC Hu, KC Lai, LY Ong, Z Gao, JS Chen, BW Chen, XW Jiang, XH Hou, JY Lu, WH Wang, K Miki, A Covacci. Department of Medicine & Pathology, University of Hong Kong, Hong Kong; Public Health Bureau, Changle, and Changle Institute for Cancer Research, Fujian, China, First Dept of Internal Medicine, University of Tokyo, Japan, and *Immunobiological Research Institute, Siena, Italy.

Conclusion.These results indicate that there is selection for particular bacterial phenotypes during chronic infection of rhesus monkeys, in particular for a pattern of Le expression related to that of the host.We propose that this exemplifies host-mimicry by H. pylori that contributes to its remarkable persistence.

Background: In areas with high prevalence of Helicobacter pylori (Hp) infection and high gastric cancer mortality such as China and Japan, Hp status is not a good marker for increased risk of gastric cancer.The increased risk associated with CagA+ Hp strains are controversial in these areas as well.Hong Kong has a moderate to high prevalence of Hp infection and a gastric cancer mortality of 7.9/105 population.We examine the relationship between Hp, particularly CagA+ strains, and gastric cancer in Hong Kong adults.Methods: Sera from 52 patients (29 male and 23 females, mean age 59.8 yrs) with non-cardiac type of gastric cancer and 52 age and sex matched asymptomatic controls were examined for anti-Hp antibody by using the commercial ELISA kit (Bio-rad, USA).CagA status was determined by an anti-CagA antibody assay using a purified recombinant CagA fusion protein as antigen using the method described(Am

There are suggestions that duodenal ulcer protects individuals from gastric cancer and that rice is ulcerogenic while wheat is gastro‐protective. We aimed to examine the relationship of gastric cancer, duodenal and gastric ulcers in different geographical regions in China and identified dietary risk factors for duodenal ulcer and gastric cancer. The prevalence of peptic ulcer and gastric cancer among symptomatic patients in eight major cities, four each from the north and the south representing all the six defined regions of China were studied. Endoscopy and case records over a 10 year period were reviewed and cases of confirmed duodenal and gastric ulcer and gastric cancer, together with the total number of endoscopies performed per year, were recorded. Rates were expressed as cases/1000 endoscopies. Results were compared to another epidemiological study on diet and mortality in the same regions in China conducted at the same time. Duodenal ulcer rates were 2.4‐fold higher in southern China than northern China, whereas gastric cancer rates were 1.6‐fold higher in the north than in the south. Correlation studies showed for the first time an inverse linear relationship between the gastric cancer rates and the duodenal ulcer rates (r=‐0.8076, P=0.015), as well as the duodenal ulcer: gastric ulcer ratios (r=‐0.9133, P=0.002). Gastric ulcer rates were higher in southern China but did not correlate with the gastric cancer rates (r=0.1455, P=0.731). Duodenal ulcer rates were found to be related to daily rice intake (r=0.8554, P=0.029) and inversely related to daily wheat flour intake (r=‐0.8472, P=0.033). Gastric cancer rates were not related to any dietary risk factors tested. We concluded there was an inverse relationship between gastric cancer rates and duodenal ulcer rates. Although duodenal ulceration and gastric cancer are both linked to Helicobacter pylori infection, the findings of this study indicate independent additional aetiological factors for the pathogenesis of these conditions. Dietary factors such as rice or wheat intake may play a role.