BACKGROUNDSalt substitutes with reduced sodium levels and increased potassium levels have been shown to lower blood pressure, but their effects on cardiovascular and safety outcomes are uncertain. METHODSWe conducted an open-label, cluster-randomized trial involving persons from 600 villages in rural China. The participants had a history of stroke or were 60 years of age or older and had high blood pressure. The villages were randomly assigned in a 1:1 ratio to the intervention group, in which the participants used a salt substitute (75% sodium chloride and 25% potassium chloride by mass), or to the control group, in which the participants continued to use regular salt (100% sodium chloride). The primary outcome was stroke, the secondary outcomes were major adverse cardiovascular events and death from any cause, and the safety outcome was clinical hyperkalemia. RESULTSA total of 20,995 persons were enrolled in the trial. The mean age of the participants was 65.4 years, and 49.5% were female, 72.6% had a history of stroke, and 88.4% a history of hypertension. The mean duration of follow-up was 4.74 years. The rate of stroke was lower with the salt substitute than with regular salt (29.14 events vs. 33.65 events per 1000 person-years; rate ratio, 0.86; 95% confidence interval [CI], 0.77 to 0.96; P = 0.006), as were the rates of major cardiovascular events (49.09 events vs. 56.29 events per 1000 person-years; rate ratio, 0.87; 95% CI, 0.80 to 0.94; P<0.001) and death (39.28 events vs. 44.61 events per 1000 person-years; rate ratio, 0.88; 95% CI, 0.82 to 0.95; P<0.001). The rate of serious adverse events attributed to hyperkalemia was not significantly higher with the salt substitute than with regular salt (3.35 events vs. 3.30 events per 1000 person-years; rate ratio, 1.04; 95% CI, 0.80 to 1.37; P = 0.76). CONCLUSIONSAmong persons who had a history of stroke or were 60 years of age or older and had high blood pressure, the rates of stroke, major cardiovascular events, and death from any cause were lower with the salt substitute than with regular salt.

Objective To determine whether an education programme targeted at schoolchildren could lower salt intake in children and their families. Design Cluster randomised controlled trial, with schools randomly assigned to either the intervention or control group. Setting 28 primary schools in urban Changzhi, northern China. Participants 279 children in grade 5 of primary school, with mean age of 10.1; 553 adult family members (mean age 43.8). Intervention Children in the intervention group were educated on the harmful effects of salt and how to reduce salt intake within the schools’ usual health education lessons. Children then delivered the salt reduction message to their families. The intervention lasted for one school term (about 3.5 months). Main outcome measures The primary outcome was the difference between the groups in the change in salt intake (as measured by 24 hour urinary sodium excretion) from baseline to the end of the trial. The secondary outcome was the difference between the two groups in the change in blood pressure. Results At baseline, the mean salt intake in children was 7.3 (SE 0.3) g/day in the intervention group and 6.8 (SE 0.3) g/day in the control group. In adult family members the salt intakes were 12.6 (SE 0.4) and 11.3 (SE 0.4) g/day, respectively. During the study there was a reduction in salt intake in the intervention group, whereas in the control group salt intake increased. The mean effect on salt intake for intervention versus control group was −1.9 g/day (95% confidence interval −2.6 to −1.3 g/day; P<0.001) in children and −2.9 g/day (−3.7 to −2.2 g/day; P<0.001) in adults. The mean effect on systolic blood pressure was −0.8 mm Hg (−3.0 to 1.5 mm Hg; P=0.51) in children and −2.3 mm Hg (−4.5 to −0.04 mm Hg; P<0.05) in adults. Conclusions An education programme delivered to primary school children as part of the usual curriculum is effective in lowering salt intake in children and their families. This offers a novel and important approach to reducing salt intake in a population in which most of the salt in the diet is added by consumers. Trial registration ClinicalTrials.gov NCT01821144.

BackgroundThroughout China, a growing number of physicians are leaving or intending to depart from their organizations owing to job dissatisfaction. Little information is available about the role of occupational burnout in this association. We set out to analyze the relationship between job satisfaction, burnout, and turnover intention, and further to determine whether occupational burnout can serve as a mediator among Chinese physicians from urban state-owned medical institutions.MethodsA cross-sectional survey was carried out in March 2010 in Hubei Province, central China. The questionnaires assessed sociodemographic characteristics, job satisfaction, burnout, and turnover intention. The job satisfaction and occupational burnout instruments were obtained by modifying the Chinese Physicians' Job Satisfaction Questionnaire (CPJSQ) and the Chinese Maslach Burnout Inventory (CMBI), respectively. Such statistical methods as one-way ANOVA, Pearson correlation, GLM-univariate and structural equation modeling were used.ResultsOf the 1600 physicians surveyed, 1451 provided valid responses. The respondents had medium scores (3.18 +/-0.73) on turnover intention, in which there was significant difference among the groups from three urban areas with different development levels. Turnover intention, which significantly and negatively related to all job-satisfaction subscales, positively related to each subscale of burnout syndrome. Work environment satisfaction (b = -0.074, p < 0.01), job rewards satisfaction (b = -0.073, p < 0.01), organizational management satisfaction (b = -0.146, p < 0.01), and emotional exhaustion (b = 0.135, p < 0.01) were identified as significant direct predictors of the turnover intention of physicians, with 41.2% of the variance explained unitedly, under the control of sociodemographic variables, among which gender, age, and years of service were always significant. However, job-itself satisfaction no longer became significant, with the estimated parameter on job rewards satisfaction smaller after burnout syndrome variables were included. As congregated latent concepts, job satisfaction had both significant direct effects (gamma21 = -0.32, p < 0.01) and indirect effects (gamma11 × beta21 = -0.13, p < 0.01) through occupational burnout (62% explained) as a mediator on turnover intention (47% explained).ConclusionsOur study reveals that several, but not all dimensions of both job satisfaction and burnout syndrome are relevant factors affecting physicians' turnover intention, and there may be partial mediation effects of occupational burnout, mainly through emotional exhaustion, within the impact of job satisfaction on turnover intention. This suggests that enhancements in job satisfaction can be expected to reduce physicians' intentions to quit by the intermediary role of burnout as well as the direct path. It is hoped that these findings will offer some clues for health-sector managers to keep their physician resource motivated and stable.

Oxygen vacancies (OVs) are important for changing the geometric and electronic structures as well as the chemical properties of MnO 2 . In this study, we performed a DFT+U calculation on the electronic structure and catalytic performance of a β-MnO 2 catalyst for oxygen reduction reaction (ORR) with different numbers and extents of OVs. Comparing to the experimental XRD analysis, we determined that OVs produce a new crystalline phase of β-MnO 2 . Changes in the electronic structure (Bader charges, band structure, partial density of states (PDOS), local density of states (LDOS), and frontier molecular orbital), proton insertion and oxygen adsorption in β-MnO 2 (110) were investigated as a function of the bulk OVs. The results show that a moderate concentration of bulk OVs reduced the band gap, increased the Fermi and HOMO levels of the MnO 2 (or MnOOH), and elongated the O-O bond of the adsorbed O 2 and co-adsorbed O 2 with H. These changes substantially increase the conductivity of MnO 2 for the catalysis of ORR. However, an excessively high concentration of OVs in β-MnO 2 (110) will work against the catalytic enhancement of MnO 2 for ORR. The DFT+U calculation reveals that a moderate concentration of OVs induced a large overlap of the surface Mn d z2 orbitals and thus introducing an extra donor level at the bottom of the conductive band (CB), which increased the conductivity of β-MnO 2 (110). Such a curvilinear change of the catalytic activity and electronic structure as a function of the oxygen vacancy concentration suggests that the β-MnO 2 with moderate concentration OVs exhibits the highest conductivity and catalytic activity for ORR.