F-53B, the commercial product of chlorinated polyfluoroalkyl ether sulfonic acids (Cl-PFESAs), has been used in Chinese chrome plating industry for 30 years, and was recently identified in the ...environment, which caused great concerns. So far, limited investigations have been performed on their environmental occurrence, fate and impact. In this study, we demonstrated the wide occurrence of Cl-PFESAs and their trophic transfer behavior in marine organisms from Chinese Bohai Sea. 6:2 Cl-PFESA (<0.016–0.575 ng/g wet weight) was the dominant congener, and 8:2 Cl-PFESA (<0.022–0.040 ng/g) was occasionally detected. Compared to other perfluoroalkyl and polyfluoroalkyl substances (PFASs) of concern, the levels of Cl-PFESAs were relatively lower in marine organisms. Based on the comparative analysis of Cl-PFESA contamination in mollusk samples collected in 2010–2014, both the concentrations and detection frequencies of Cl-PFESAs tended to increase in this region. And this kind of chemicals were more vulnerable to be accumulated in marine organisms at relatively higher trophic levels. Similar to perfluorooctanesulfonate (PFOS) and the long chain perfluorinated carboxylates (PFCAs), 6:2 Cl-PFESA could be magnified along the food chain. Accordingly, the potential threat might be posed to the wildlife and human beings due to unintended exposure to Cl-PFESAs.
Although the abiotic and biotic transformation/degradation (T/D) processes of tetrabromobisphenol A (TBBPA) have been widely investigated in model experiments, few reviews have focused on these ...processes along with their metabolites or degradation products. In this paper, we summarize the current knowledge on the T/D of TBBPA and its derivatives, including abiotic and biotic T/D strategies/conditions, mechanisms, metabolites and environmental occurrences. Various treatments, such as pyrolysis, photolysis, chemical reactions and biotransformation, have been employed to study the metabolic mechanism of TBBPA and its derivatives and to remediate associated contaminated environments. To date, more than 100 degradation products and metabolites have been identified, dominated by less brominated compounds such as bisphenol A, 2,6-dibromo-4-isopropylphenol, 2,6-dibromo-4-hydroxyl-phenol, 2,6-dibromophenol, isopropylene-2,6-dibromophenol, 4-(2-hydroxyisopropyl)-2,6-dibromophenol, etc. It can be concluded that the T/D of TBBPA mainly takes place through debromination and β-scission. In some environmental media and human and animal tissues, brominated metabolites, glucoside and sulfate derivatives are also important T/D products. Here, the T/D products of TBBPA and its derivatives have been most comprehensively presented from the literature in recent 20 years. This review will enhance the understanding of the environmental behaviors of TBBPA-associated brominated flame retardants along with their ecological and health risks.
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•Transformation/degradation (T/D) of TBBPA is most comprehensively reviewed.•T/D is involved in thermo-treatment, chemical reaction, microbe, organism, etc.•Debromination and β-scission are the main T/D pathways.•More than 100 intermediates or metabolites have been identified in recent years.•Fate and risk of metabolites are rarely studied for the lack of purity standards.
T/D of TBBPA and its derivatives, including strategies/conditions, mechanism, metabolites and environmental occurrence is most systematically reviewed from the literature over the past 20 years.
In this paper, 65 pesticides, including banned ones of DDTs, etc. and non-banned ones of iprobenfos, etc. have been detected in 31 surface sediment samples from the East China Sea (ECS) to study ...their pollution levels, sources, and risks. There were 8 banned pesticides (90–97%) and 10 non-banned pesticides (26–100%) presenting higher detection frequencies. For the 18 pesticides detected, their total contents ranged from 183.49 to 1363.77 ng/g dry weight (d.w.) and presented a seaward decreasing trend. Higher contents of banned pesticides were concentrated in the inner shelf close to Zhoushan Island. Iprobenfos, one of non-banned pesticides, showed the highest detection frequency (100%) and pollution level (79.14–1169.18 ng/g d.w.), indicating its continuous input in recent years. The pesticides concentrations in water calculated by the equilibrium partitioning (EqP) method were lower than the toxicological endpoint for tested aquatic invertebrates and fish, indicating ecological risks of these pesticides were at low levels.
•Eighteen banned and non-banned pesticides showed detection frequency of 26–100%.•Non-banned pesticides showed a seaward decreasing trend.•Levels of iprobenfos in sediments of coast areas of China were firstly reported.•Iprobenfos was the representative non-banned pesticides with highest contents.•Terrestrial input was continuous for non-banned pesticides.
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•3D MnCo2O4@MnMoO4 CSNs on NF have been constructed.•The CSNs were built by growing MnMoO4 nanosheets onto MnCo2O4 NAs.•Such CSNs exhibit a high specific capacity of 885 C g−1 at ...3 A g−1.•95% capacitance retention are be achieved after 5000 cycles at 10 A g−1.•The assembled ASC delivers an energy density of 49.4 W h kg−1 at 815 W kg−1.
Rational design and fabrication of core-shell nanoarrays (CSNs) with distinctive architectures and desirable capacitive performances are believed to be a promising and challenging strategy toward advanced electrode materials for supercapacitors (SCs). In this work, we report a two-step synthesis of three-dimensional (3D) MnCo2O4 nanosheets@MnMoO4 nanosheets CSNs on Ni foam (NF), which are constructed by vertically growing MnMoO4 nanosheets onto interconnected MnCo2O4 nanosheets arrays (NAs). Such MnCo2O4@MnMoO4 CSNs can make full use of its unique 3D architecture and the synergistic effect between MnCo2O4 and MnMoO4. Therefore, the prepared MnCo2O4@MnMoO4 CSNs, as a binder-free electrode for SCs, demonstrate a significantly enhanced specific capacity (885 C g−1 at 3 A g−1), higher rate capability (629 C g−1 at 30 A g−1), and better cycling stability (95% capacitance retention after 5000 cycles at 10 A g−1) compared with the single MnCo2O4 or MnMoO4 NAs electrode. Moreover, the assembled asymmetric SC cell (ASC) based on MnCo2O4@MnMoO4//activated carbon (AC) also exhibits a specific capacity (222 C g−1 at 1 A g−1) and an energy density (49.4 W h kg−1 at 815 W kg−1), indicating a promising practical application for the prepared MnCo2O4@MnMoO4 CSNs in high-performance SCs.
•All selected articles were cohort studies, which could better provide a causal relationship of the analyzed factors than a cross-sectional design.•Our meta-analysis include the analysis of both ...crude and adjusted HR of cohort studies about the relationship between sarcopenia and fracture. By reporting pooled effect size of unadjusted and adjusted data, we present all available evidence on this topic.
The association between sarcopenia and risk of fracture remained controversial. This systematic review and meta-analysis was conducted to evaluate the association between sarcopenia and fracture incidence in the middle-aged and elderly people.
Web of Science, PubMed, EMBASE, and the Cochrane Library were searched. Weighted averages were reported as hazard risk (HR) values with 95% confidence interval (CI). Statistical heterogeneity scores were assessed with the standard Cochran's Q test and the I2 statistic.
A total of 5 cohort studies involving 27 990 participants were included in our study. The crude and adjusted effect sizes between sarcopenia and fracture were extracted from 2 and 5 studies, respectively. Sarcopenia was significantly associated with fracture incidence without adjusting covariates (crude HR, 1.69; 95% CI, 1.34–2.13). After adjusting for potential confounders, sarcopenia still demonstrated significant positive association with fracture (adjusted HR, 1.50;95%CI, 1.08–2.08). The sensitivity analysis confirmed the stability of the results. In the subgroup analysis of studies after adjusting covariates, there were significant associations between sarcopenia and fracture in the subgroups of male, older people, American and hip fracture patients.
Our meta-analysis found that sarcopenia was significantly associated with fracture in middle aged and elderly people. However, more homogeneous studies are needed to fully clarify the relationship between sarcopenia and fracture.
Intra-articular injection of mesenchymal stem cells (MSCs) in an osteoarthritic joint can help slow down cartilage destruction. However, cell survival and the efficiency of repair are generally low ...due to mechanical damage during injection and a high rate of cell loss. We, thus, investigated an improved strategy for cell delivery to an osteoarthritic joint through the use of three-dimensional (3D) microcryogels. MSCs were seeded into 3D microcryogels. The viability and proliferation of MSCs in microcryogels were determined over 5 d, and the phenotype of MSCs was confirmed through trilineage differentiation tests and flow cytometry. In Sprague Dawley rats with induced osteoarthritis (OA) of the knee joint, a single injection was made with the following groups: saline control, low-dose free MSCs (1 × 105 cells), high-dose free MSCs (1 × 106 cells), and microcryogels + MSCs (1 × 105 cells). Cartilage degeneration was evaluated by macroscopic examination, micro-computed tomographic analysis, and histology. MSCs grown in microcryogels exhibited optimal viability and proliferation at 3 d with stable maintenance of phenotype in vitro. Microcryogels seeded with MSCs were, therefore, primed for 3 d before being used for in vivo experiments. At 4 and 8 wk, the microcryogels + MSCs and high-dose free MSC groups had significantly higher International Cartilage Repair Society macroscopic scores, histological evidence of more proteoglycan deposition and less cartilage loss accompanied by a lower Mankin score, and minimal radiographic evidence of osteoarthritic changes in the joint compared to the other two groups. In conclusion, intra-articular injection of cell-laden 3D microcryogels containing a low dose of MSCs can achieve similar effects as a high dose of free MSCs for OA in a rat model. Primed MSCs in 3D microcryogels can be considered as an improved delivery strategy for cell therapy in treating OA that minimizes cell dose while retaining therapeutic efficacy.
In this study, 166 surface sediments and 3 sediment cores from the Bohai Sea (BS), Yellow Sea (YS) and East China Sea (ECS) in China were collected to investigate the spatial and temporal ...distributions and the transport of PFASs. PFASs concentrations in the surface sediments ranged from below detection limit (<LOD) to 2.78 ng g−1 with an average value of 0.55 ng g−1 on a dry weight basis (dw). A general decreasing trend of PFASs from the coast areas to the open sea was found. Multivariate regression analysis indicated pH and longitude were the major factors influencing surficial distributions of PFASs in the sampling areas (R2 = 0.29, p < 0.01). Total PFASs concentrations in the sediment cores ranged from <LOD to 1.65 ng g−1 dw, with an increasing trend from the lower to the upper layers, corresponding well to the increasing production and usage in China in recent years.
•A general decreasing trend of PFASs from the coast areas to the open sea was found.•The major factors influencing spatial distributions of PFASs were pH and longitude.•Sediment cores showed increasing trend of PFASs from the lower to the upper layers.
PFASs concentrations in the sediments from the China seas were moderate and the most important factor influencing the spatial distributions was pH.
HIV testing rates are suboptimal among at-risk men. Crowdsourcing may be a useful tool for designing innovative, community-based HIV testing strategies to increase HIV testing. The purpose of this ...study was to use a stepped wedge cluster randomized controlled trial (RCT) to evaluate the effect of a crowdsourced HIV intervention on HIV testing uptake among men who have sex with men (MSM) in eight Chinese cities.
An HIV testing intervention was developed through a national image contest, a regional strategy designathon, and local message contests. The final intervention included a multimedia HIV testing campaign, an online HIV testing service, and local testing promotion campaigns tailored for MSM. This intervention was evaluated using a closed cohort stepped wedge cluster RCT in eight Chinese cities (Guangzhou, Shenzhen, Zhuhai, and Jiangmen in Guangdong province; Jinan, Qingdao, Yantai, and Jining in Shandong province) from August 2016 to August 2017. MSM were recruited through Blued, a social networking mobile application for MSM, from July 29 to August 21 of 2016. The primary outcome was self-reported HIV testing in the past 3 months. Secondary outcomes included HIV self-testing, facility-based HIV testing, condom use, and syphilis testing. Generalized linear mixed models (GLMMs) were used to analyze primary and secondary outcomes. We enrolled a total of 1,381 MSM. Most were ≤30 years old (82%), unmarried (86%), and had a college degree or higher (65%). The proportion of individuals receiving an HIV test during the intervention periods within a city was 8.9% (95% confidence interval CI 2.2-15.5) greater than during the control periods. In addition, the intention-to-treat analysis showed a higher probability of receiving an HIV test during the intervention periods as compared to the control periods (estimated risk ratio RR = 1.43, 95% CI 1.19-1.73). The intervention also increased HIV self-testing (RR = 1.89, 95% CI 1.50-2.38). There was no effect on facility-based HIV testing (RR = 1.00, 95% CI 0.79-1.26), condom use (RR = 1.00, 95% CI 0.86-1.17), or syphilis testing (RR = 0.92, 95% CI 0.70-1.21). A total of 48.6% (593/1,219) of participants reported that they received HIV self-testing. Among men who received two HIV tests, 32 individuals seroconverted during the 1-year study period. Study limitations include the use of self-reported HIV testing data among a subset of men and non-completion of the final survey by 23% of participants. Our study population was a young online group in urban China and the relevance of our findings to other populations will require further investigation.
In this setting, crowdsourcing was effective for developing and strengthening community-based HIV testing services for MSM. Crowdsourced interventions may be an important tool for the scale-up of HIV testing services among MSM in low- and middle-income countries (LMIC).
ClinicalTrials.gov NCT02796963.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Due to the endocrine disturbing effects of bisphenol A (BPA) on organisms, rapid detection has become one of the most important techniques for monitoring its levels in the aqueous solutions ...associated with plastics and human beings. In this paper, a glassy carbon electrode (GCE) modified with molybdenum selenide/reduced graphene oxide (MoSe₂/rGO) was fabricated for in situ determination of bisphenol A in several beverages. The surface area of the electrode dramatically increases due to the existence of ultra-thin nanosheets in a flower-like structure of MoSe₂. Adding phosphotungstic acid in the electrolyte can significantly enhance the repeatability (RSD = 0.4%) and reproducibility (RSD = 2.2%) of the electrode. Under the optimized condition (pH = 6.5), the linear range of BPA was from 0.1 μM⁻100 μM and the detection limit was 0.015 μM (S/
= 3). When using the as-prepared electrode for analyzing BPA in beverage samples without any pretreatments, the recoveries ranged from 98⁻107%, and the concentrations were from below the detection limit to 1.7 μM, indicating its potential prospect for routine analysis of BPA.
Owing to the advantages of transient, broadband, low-energy, transmission and high frequency accuracy, terahertz frequency domain spectroscopy (THz-FDS) has been introduced and pioneered for ...determining chlortetracycline hydrochloride (CCH) and tetracycline hydrochloride (TCH) in environmental samples, such as chicken, rice and soils. Their THz fingerprint spectra were located in the range of 0.4–1.1 THz, with the peaks at 0.49, 0.60, 0.76, 0.90 and 1.03 THz for CCH and at 0.52, 0.67, 0.79, 0.92 and 1.05 THz for TCH, respectively. By simple pressing treatment, dry soil, chicken and rice samples spiked with standards can be used for direct analysis. For the quantitative analysis, partial least squares regression (PLSR) algorithms were utilized for optimizing the analysis accuracy, calculation and prediction. Lower root mean square error of cross validation (RMSECV < 0.1689), calibration (RMSEC < 0.0623), prediction (RMSEP < 0.1280) and higher correlation coefficient (R > 0.9089) for these two compounds in soil, chicken and rice samples have been obtained. Our results indicated that THz-FDS combined with PLSR model could be a useful analytical technique for monitoring CCH and TCH in environmental samples.
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•THz-FDS was firstly introduced for qualitative and quantitative analysis of CCH and TCH in soil, chicken and rice samples.•Samples spiked with CCH and TCH can be directly analyzed without complex separation and purification process.•PLSR algorithms were chosen for calculating and predicting the contents of CCH and TCH.
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