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1.
Nanoscale ; 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32150185

RESUMO

Hierarchical porosity and functionalization are recognized as two crucial parameters in mediating the catalytic performance of heterogeneous catalysts, however, they are rarely achieved simultaneously in the development of metal-organic frameworks (MOFs). In this work, a simple and efficient method has been developed to synchronously construct hierarchical porosity and functionalization within a sulfonic acid group functionalized microporous MOF via a palladium-reduction induced strategy, for the first time. The generation mechanism of the mesopore has been explained using two-dimensional 1H DQ-SQ MAS NMR. The content of the mesopore and the active sites within mesoPd@NUS-6 could be finely tuned by simply controlling Pd loading. Particularly, the combination of hierarchical porosity and functionalization, as well as the ultra-stable structure endow the composites with great potential in bulk, for adsorption and heterogeneous catalysis.

2.
J Environ Sci (China) ; 91: 1-9, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32172957

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are a typical class of persistent organic pollutants that is ubiquitous worldwide. Previous animal studies suggested that PAHs had adverse effects on female reproduction. However, the human data regarding relationship of PAHs exposure with women reproductive health, such as ovarian dysfunction, are scarce. In this case-control study, the associations of serum levels of PAHs with the risk of premature ovarian failure (POF) and reproductive hormones in Chinese women were investigated, with recruiting 157 POF patients and 217 healthy women. The serum levels of 12 types of PAHs, as well as reproductive hormones, including follicle-stimulating hormone, luteinizing hormone and anti-mullerian hormone, were determined. In the logistic regression models, most individual PAH congeners showed significantly positive correlations with the risk of POF (p < 0.05), except for fluorine and pyrene. Benzo(a)pyrene (BaP), as the most carcinogenic PAH congener, was observed to be significantly positively associated with the risk of POF. After adjustment for age, body mass index, educational levels and household income, per one-unit increase in the log-transformed BaP concentration was significantly correlated with 2.191-fold increased risk of POF (OR = 2.191, 95%CI: 1.634-2.938, p < 0.05). To the best of our knowledge, this is the first study to report an association between internal exposure levels of PAHs and the increased risk of POF in women.

3.
BMC Complement Med Ther ; 20(1): 82, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32164649

RESUMO

BACKGROUND: Daily "eye exercises," massaging of periocular acupuncture pressure points, have been part of China's national vision care policy in schools for some 50 years. However, the effect of eye exercises on myopia progression and eyeglasses wear has not been definitively investigated. This study evaluates the effectiveness of eye exercises on visual acuity and the propensity of rural children to wear eyeglasses. METHODS: Cohort study in 252 randomly-selected rural schools with baseline in September 2012 and follow up surveys 9 and 21 months later. Outcomes were assessed using propensity-score matching (PSM), multivariate linear regression and logistic regression to adjust for differences between children performing and not performing eye exercises. RESULTS: Among 19,934 children randomly selected for screening, 2374 myopic (spherical equivalent refractive error ≤ - 0.5 diopters in either eye) children (11.9%, mean age 10.5 [Standard Error 1.08] years, 48.5% boys) had VA in either eye ≤6/12 without eyeglasses correctable to > 6/12 with eyeglasses. Among these who completed the 21-month follow up, 1217 (58.2%) children reported practicing eye exercises on school days and 874 (41.8%) did not. After propensity-score matching, 1652 (79%) children were matched: 826 (50%) in the Eye Exercises group and 826 (50%) in the No Exercise group. Performing eye exercises was not associated with change in LogMAR uncorrected visual acuity and wear of eyeglasses, using either logistic regression or PSM at 9 or 21 months. CONCLUSIONS: We found no evidence for an effect of eye exercises on change in vision or eyeglasses wear. TRIAL REGISTRATION: The original trial (Registration site: http://isrctn.org. Registration number: ISRCTN03252665) was retrospectively registered 25/09/2012.

4.
Inorg Chem ; 59(3): 1736-1745, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31927961

RESUMO

With fossil energy resources increasingly drying up and gradually causing serious environmental impacts, pursuing a tandem and green synthetic route for a complex and high-value-added compound by using low-cost raw materials has attracted considerable attention. In this regard, the selective and efficient conversion of light olefins with CO2 into high-value-added organic cyclic carbonates (OCCs) is of great significance owing to their high atom economy and absence of the isolation of intermediates. To fulfill this expectation, a multifunctional catalytic system with controllable spatial arrangement of varied catalytic sites and stable texture, in particular, within a single catalyst, is generally needed. Here, by using a stepwise electrostatic interaction strategy, imidazolium-based ILs and Au nanoparticles (NPs) were stepwise immobilized into a sulfonic group grafted MOF to construct a multifunctional single catalyst with a highly ordered arrangement of catalytic sites. The Au NPs and imidazolium cation are separately responsible for the selective epoxidation and cycloaddition reaction. The mesoporous cage within the MOF enriches the substrate molecules and provides a confined catalytic room for the tandem catalysis. More importantly, the highly ordered arrangement of the varied active sites and strong electrostatic attraction interaction result in the intimate contact and effective mass transfer between the catalytic sites, which allow for the highly efficient (>74% yield) and stable (repeatedly usage for at least 8 times) catalytic transformation. The stepwise electrostatic interaction strategy herein provides an absolutely new approach in fabricating the controllable multifunctional catalysts, especially for tandem catalysis.

5.
J Hazard Mater ; 383: 121132, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31518813

RESUMO

To investigate the effect of salinity (1% sodium chloride) on anaerobic microbial community structure in high strength telephthalic wastewater treatment system, the performances of anaerobic-aerobic process and the shifts of microbial community in anaerobic tank were studied and determined. Results showed that the chemical oxygen demand (COD) removal in the whole process remained above 90%. And the effluent concentrations of targeted pollutants were lower than 10 mg/L, other than para-toluic acid (PT, 38.09 mg/L). However, methane production significantly decreased compared to no salinity situation. This might be due to the inhibition of salinity on methanogens, which hindered the conversion of acetate to methane. Furthermore, the dominant genus in bacterial level changed from Tepidisphaera to Syntrophus, which facilitated the syntrophic association with hydrogenotrophic methanogens. The prevailed archaea remained acetoclastic Methanothrix above 90%. Therefore, the salinity on anaerobic microbial community structure mainly reflects in the methanogen process, remarkably decreasing methane production.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31795178

RESUMO

Background: To provide an updated estimate of the level and change in catastrophic health expenditure in China and examine the association between catastrophic health expenditure and family net income, we obtained data from four waves of the China Family Panel Studies conducted between 2010 and 2016. Method: We defined catastrophic health expenditure as out-of-pocket payments equaling or exceeding 40% of the household's capacity to pay. The Poisson regression with robust variance and generalized estimated equation (Poisson-GEE) model was used to quantify the level and change of catastrophic health expenditure, as well as the association between catastrophic heath expenditure and family net income. Result: Overall, the incidence of catastrophic expenditure in China experienced a 0.70-fold change between 2010 (12.57%) and 2016 (8.94%). The incidence of catastrophic health expenditure (CHE) decreased more in the poorest income quintile than the richest income quintile (annual decrease of 1.17% vs. 0.24% in urban areas, p < 0.001; 1.64% vs. -0.02% in rural areas, p < 0.001). Every 100% increase in income was associated with a 14% relative-risk reduction in CHE (RR = 0.86, 95% CI: 0.85-0.88) after adjusting for demographics, health needs, and health utilization characteristics; this association was weaker in recent years. Conclusion: Our analysis found that China made progress to reduce catastrophic health expenditure, especially for poorer groups. Income growth is strongly associated with this change.

7.
Adv Mater ; 31(52): e1904969, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31736178

RESUMO

Hierarchical porosity and functionalization help to fully make use of metal-organic frameworks (MOFs) for their diverse applications. Herein, a simple strategy is reported to construct hierarchically porous MOFs through a competitive coordination method using tetrafluoroborate (M(BF4 )x , where M is metal site) as both functional sites and etching agents. The resulting MOFs have in situ formed defect-mesopores and functional sites without sacrificing their structure stability. The formation mechanism of the defect-mesopores is elucidated by a combination of experimental and first-principles calculation method, indicating the general feasibility of this new approach. Compared with the original microporous counterparts, the new hierarchical MOFs exhibit superior adsorption for the bulky dye molecules and catalytic performance for the CO2 conversion attributed to their specific hierarchical pore structures.

8.
Emerg Infect Dis ; 25(12): 2274-2277, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31742514

RESUMO

During 2013-2017, a total of 211 cases of listeriosis were reported by 64 sentinel hospitals in China to a national foodborne disease surveillance network. The average case-fatality rate was 31.2% for perinatal cases and 16.4% for nonperinatal cases. Sequence types 87 and 8 were the most prevalent types.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31775283

RESUMO

OBJECTIVES: Evidence of school-based physical activity (PA) on academic performance in children and adolescents was inconsistent, especially in high school students who face a high academic burden. In this study, we tested the efficacy of a strengthened physical education (PE) program on academic outcomes in Shanghai. METHODS: A quasi-experimental design was conducted to investigate the effect of strengthened PE on academic scores by calculating the grade-cohort difference before and after the intervention. PE curriculum switched from traditional short duration (40 minutes) general fitness training to long duration (90 minutes) specialized sports (e.g., football, aerobics). A total of 460 high school students (236 pre-intervention and 224 post-intervention) were enrolled in grade 10 and followed for two and three semesters. The academic outcome was assessed by district-standardized test scores. A difference-in-difference approach was employed. RESULTS: After two semesters, the standardized Chinese language scores and English language scores for the post intervention group were increased by 0.61 SD (95% confidence interval (CI): 0.44, 0.78, p < 0.001) and 0.28 SD (95% CI: 0.09, 0.47, p = 0.01). However, the standardized math scores for the post intervention group were decreased in girls. After three semesters, standardized Chinese language scores for the post intervention group were increased by 0.27 SD (95% CI: 0.06, 0.48, p = 0.01). Math scores and English language scores decreased by 0.18 SD (95% CI: -0.36, -0.01, p = 0.04) and 0.23 SD (95% CI: -0.38, -0.09, p = 0.00), respectively. CONCLUSION: A school-based physical education program had mixed effects on academic scores in high school students.

10.
BMC Infect Dis ; 19(1): 910, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664944

RESUMO

BACKGROUND: On September 4, 2018, a boarding school in the Shunyi District of Beijing, China reported an outbreak of acute gastroenteritis. At least 209 suspected students caused of diarrhea and vomiting. The case was investigated, and control measures were taken to prevent further spread. METHODS: A retrospective cohort study was conducted among the school students and staff in order to test hypothesis that high risk of food served at the school canteen. We collected information on demographics, refectory records, person to person transmission by uniform epidemiological questionnaire. Risk ratios (RR) and 95% confidence intervals (CI) were calculated. Stool specimens of cases and canteen employees, retained food, water, and environmental swabs were investigated by laboratory analysis. RESULTS: We identified 209 cases (including 28 laboratory-confirmed cases) which occurred from August 29 to September 10. All cases were students, and the average age was 20, 52% were male. The outbreak lasted for 13 days, and peaked on September 5. Consumption of Drinks stall and Rice flour stall on September 1 (RR:3.4, 95%CI:1.5-7.8, and RR:7.6, 95%CI:2.8-20.2), Rice flour stall and Fish meal stall on September 2 (RR:4.0, 95%CI:1.2-13.6, and RR:4.6, 95%CI:1.7-12.5), muslim meal stall on September 4 (RR:2.7, 95%CI:1.3-5.4), Barbeque stall on September 5 (RR:3.0, 95%CI:1.2-7.0) were independently associated with increased risk of disease within the following 2 days. Among 35 specimens of rectal swabs or feces from students, 28 specimens were positive. Norovirus GI.6 alone was detected in 23 specimens, Bacillus cereus alone in 3 specimens and both norovirus GI.6 and Bacillus cereus in 2 specimens. Ten specimens of rectal swabs from canteen employees were positive for norovirus GI, and 2 specimens were positive for Bacillus cereus. Four retained food specimens were positive for Bacillus cereus, and environmental samples were negative for any viruses or bacteria. CONCLUSION: Our investigation indicated that canteen employees were infected by two pathogens (norovirus and Bacillus cereus) and transmission may have been possible due to unhygienic practices. Student consumption of food or drink at high-risk stalls was determined as the probable cause of the outbreak.


Assuntos
Bacillus cereus/isolamento & purificação , Infecções por Caliciviridae/epidemiologia , Surtos de Doenças , Doenças Transmitidas por Alimentos/microbiologia , Gastroenterite/epidemiologia , Norovirus/isolamento & purificação , Adolescente , Pequim/epidemiologia , Infecções por Caliciviridae/complicações , Diarreia/complicações , Fezes/microbiologia , Fezes/virologia , Feminino , Contaminação de Alimentos , Doenças Transmitidas por Alimentos/virologia , Gastroenterite/complicações , Higiene das Mãos , Humanos , Masculino , Razão de Chances , Estudos Retrospectivos , Inquéritos e Questionários , Universidades , Vômito/complicações , Adulto Jovem
11.
Wei Sheng Yan Jiu ; 48(4): 589-593, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601340

RESUMO

OBJECTIVE: To estimate the burden of foodborne acute gastrointestinal illness(AGI) in community residents, and to provide the basis for prevention and control of foodborne diseases. METHODS: Muli-stage stratified random cluster sampling was used to select samples in community population. A retrospective cross-sectional face-to-face household interviews were conducted over a 12-month period. Respondents were asked questions about vomiting and diarrhea within the 28 days prior to the interviews, healthcare seeking behavior and the related cost due to AGI. RESULTS: There were 0. 15(95%CI 0. 13-0. 16)AGI episodes per person-year, foodboren infection resulted in 911975 AGI cases. About 290 190 cases sought healthcare, resulting in 9120 hospitallizations. The overall economic burden of foodborne AGI was 147 million Yuan per year, accounting for 0. 07᾿of the GDP. The direct cost of medical care was 107 million Yuan(medical costs and non-medical cost were 9. 4 million and 1. 2 million), and the direct cost was 4 million Yuan. CONCLUSION: The burden of foodborne AGI in Beijing should not be ignored. It is necessary to improve the foodborne disease surveillance system to more accurately assess the impact of foodborne disease on society and health.


Assuntos
Doenças Transmitidas por Alimentos/epidemiologia , Gastroenteropatias/epidemiologia , Pequim/epidemiologia , Efeitos Psicossociais da Doença , Estudos Transversais , Diarreia , Humanos , Estudos Retrospectivos
12.
Data Brief ; 26: 104430, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31516952

RESUMO

The dataset presented in this article supports "Selected persistent organic pollutants associated with the risk of primary ovarian insufficiency in women" (Pan et al., 2019). The supplementary data were as follows: (1) Detailed information regarding pretreatment methods, instrumental analysis and methods validation of quantification of serum concentrations of persistent organic pollutants (POPs). (2) The total dioxin equivalents (TEQs) levels of dioxin-like PCBs (DL-PCBs) in primary ovarian insufficiency (POI) cases and controls, as well as the association of TEQ levels with the risk of POI. (3) The results of principal components analyses (PCA) about 20 POPs that were detected in >40% samples.

13.
Sci Rep ; 9(1): 13784, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31551504

RESUMO

Dew collection is significant in harvesting water and relieving water shortages in arid regions. However, current methods for collecting dew or steam are mainly focusing on the millimeter-sized droplets condensed on the superhydrophobic surfaces. Here, we present a concept for harvesting micro droplets that can spontaneously bounce on the cooling superhydrophobic aluminum surface with randomly micro-nano composite structures, which were fabricated by using a two-step surface structural process. Moreover, an integrated device has been developed, which consists of a triboelectric nanogenerator and the superhydrophobic aluminum sheet. We experimentally explained that the triboelectric nanogenerator, which provides an external electric field by converting wind energy to electric energy with DC voltage pulse peaks of about 60 V, can be utilized to enhance the collection capacity of the jumping water droplets.

14.
J Colloid Interface Sci ; 557: 207-215, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521970

RESUMO

The development of a suitable catalytic system in the single catalyst has always been the pursuit for synthetic chemists in order to perform the traditional stepwise reactions in one-pot mode. In this work, an ultra-stable bifunctional catalyst of Pd@MIL-101-SO3H was successfully constructed and applied in the one-pot oxidation-acetalization reaction whose products have been widely utilized as fuel additives, perfumes, pharmaceuticals and polymer chemistry. The excellent catalytic performance (>99% yields), on the one hand, can be ascribed to the synergistic effects of Pd NPs with both Lewis and Bronsted acid encapsulated within a sulfonated MIL-101(Cr). On the other hand, the exceptionally high capacity of water adsorption in MIL-101(Cr) could promote the equilibrium movement via interrupting the reversible process. More importantly, Pd@MIL-101-SO3H is recyclable and can be reused for at least 8 times without sacrificing its catalytic activities. As far as we know, this is the first time that a water adsorption enhanced equilibrium movement of reversible reaction by porous catalyst to achieve high yields has been realized in Pd@MIL-101-SO3H, which may provide an absolutely new and efficient strategy especially for designing reaction-oriented catalysts.

15.
Bioresour Technol ; 293: 122074, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491652

RESUMO

Effect of pH on waste activated sludge (WAS) hydrolysis and decomposition treating with lysozyme and rhamnolipid combined (Ly + RL) was investigated in this study. Results showed that Ly + RL system could significantly improve the release of soluble organic matters at the optimal RL dosage of 0.3 g/gSS and lysozyme dosage of 0.15 g/gSS. Alkali conditions showed better effect than that of acid on the release of soluble organics, improvement of WAS biodegradability and reduction of big floc size within Ly + RL treatment system and the optimal pH was 10. And 9591.6 mg/L soluble chemical oxygen demand (SCOD), 1612.0 mg/L protein and 1211.6 mg/L polysaccharide were released at pH10 after 12 h co-digestion. 83.7% bacteria and 92.2% archaea were decomposed at pH10. Class Gammaproteobacteria (82.4%) was the predominant bacteria after treated by Ly + RL system, and the treated WAS was beneficial for the subsequent organics bio-degradation and volatile fatty acids accumulation.


Assuntos
Muramidase , Esgotos , Glicolipídeos , Concentração de Íons de Hidrogênio , Hidrólise , Eliminação de Resíduos Líquidos
16.
Patient Prefer Adherence ; 13: 1111-1123, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371928

RESUMO

Purpose: Hypertension is a rapidly growing epidemic in People's Republic of China, yet it remains inadequately controlled. This study aimed to identify the relative contributions of program effects and patients' characteristics to the differences in antihypertensive medication nonadherence between drug benefit program enrollees and non-enrollees. Patients and methods: Data were from a cross-sectional survey of 1,969 community-dwelling elderly adults with hypertension. Self-reported adherence was measured following previous studies in People's Republic of China. The Blinder-Oaxaca nonlinear decomposition method was used to identify the relative contributions of program effects and patients' individual characteristics. Results: Eleven percent of the drug benefit program enrollees were nonadherent to their medication, while 17% of non-enrollees were. Blinder-Oaxaca decomposition identified that over 60% of the gap between the two groups was due to the program effects (P=0.024). The rest could be explained by differences in observable characteristics (P<0.001), such as diabetic status, duration of hypertension, and blood pressure control. Conclusion: The study confirmed that drug benefit program enrollees were more likely to be adherent to their antihypertensive medication than non-enrollees in the context of People's Republic of China.

17.
J Med Internet Res ; 21(7): e14210, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31359864

RESUMO

BACKGROUND: Cognitive decline is a major risk factor for disability and death and may serve as a precursor of dementia. Digital devices can provide a platform of cognitively stimulating activities which might help to slow cognitive decline during the process of normal aging. OBJECTIVE: This longitudinal study aimed to examine the independent protective factors of desktop and cellphone ownership against cognitive decline in mid-life and older adulthood and to examine the combined effect of desktop and cellphone ownership on the same outcome. METHODS: Data was obtained from a China Health and Retirement Longitudinal Studies (CHARLS) cohort made up of 13,457 community-dwelling adults aged 45 years or above in 2011-2012. They were followed for 4 years, with baseline measurements taken as well as 2 two-year follow-up visits. Cognitive function was tested during the baseline test and follow-up visits. A global cognition z-score was calculated based on two domains: word recall and mental intactness. The key independent variables were defined as: whether one had desktops with internet connection at home and whether one had a cellphone. An additional categorical variable of three values was constructed as: 0 (no desktop or cellphone), 1 (desktop or cellphone alone), and 2 (desktop and cellphone both). Mixed-effects regression was adjusted for demographic and health behavior as well as health condition risk factors. RESULTS: Adjusted for demographic and health behavior as well as health condition risk factors, desktop and cellphone ownership were independently associated with subsequent decreased cognitive decline over the four-year period. Participants without a desktop at home had an adjusted cognitive decline of -0.16 standard deviations (95% CI -0.18 to -0.15), while participants with a desktop at home had an adjusted cognitive decline of -0.10 standard deviations (95% CI -0.14 to -0.07; difference of -0.06 standard deviations; P=.003). A similar pattern of significantly protective association of 0.06 standard deviations (95% CI 0.03-0.10; P<.001) between cellphone ownership and cognitive function was observed over the four-year period. Additionally, a larger longitudinal protective association on cognitive decline was observed among those with both of the digital devices, although the 95% CIs for the coefficients overlapped with those with a single digital device alone. CONCLUSIONS: Findings from this study underscored the importance of digital devices as platforms for cognitively stimulating activities to delay cognitive decline. Future studies focusing on use of digital devices are warranted to investigate their longitudinal protective factors against cognitive decline at mid- and later life.

18.
Bioresour Technol ; 289: 121703, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31271912

RESUMO

Feasibility of combined lysozyme and rhamolipid (RL) pretreatment on the enhancement of excess sludge (ES) hydrolysis and decomposition was assessed in this study. Results showed lysozyme and RL combined treatment could significantly promote ES hydrolysis and decomposition, an additional 1196.9 mg/L soluble chemical oxygen demand (SCOD), 792.5 mg/L protein and 133.5 mg/L polysaccharide were released compared with the sum of sole RL and sole lysozyme treatment at the optimal RL dosage of 0.3 g/gSS and lysozyme dosage of 0.15 g/gSS after 8 h co-digestion. 45.3% bacteria and 84.5% archaea decomposition degree were gained under the combined treatment at the optimal RL dosage. Class Gammaproteobacteria and genus Methanothrix were the predominant bacteria and archaea with the relative abundance of 72.4% and 60.8%, respectively. After the combined pretreatment, ES was beneficial for volatile fatty acids accumulation and acetic acid dependent methane generating inferred from the results of microbial community composition.


Assuntos
Glicolipídeos/metabolismo , Muramidase/metabolismo , Esgotos/microbiologia , Archaea/metabolismo , Bactérias/metabolismo , Análise da Demanda Biológica de Oxigênio , Ácidos Graxos Voláteis/biossíntese , Hidrólise , Metano/metabolismo , Microbiota
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