This study was designed to evaluate the epidemiology and clinical characteristics on metabolic syndrome (MetS) among overweight and obese children aged from 6 to 13 years old in Kazakh ethnic ...populations.
Based on the data including body mass index (BMI), waist circumference (WC) and blood pressure measured from the 'Kazakh ethnic child Health examination study in Yili', 5360 Kazakh children aged 6 - 13 were screened for overweight and obesity in Xinjiang, using the Chinese BMI cutoffs for schoolchildren (7 - 18 years) and WHO growth reference for school-aged children and adolescents (6 year). Simultaneously a group of children with normal BMI were selected as the control group. Fasting plasma glucose (FPG), insulin (FINS), serum high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) were examined. HOMA-IR index was calculated to estimate the individual insulin resistance. Children under study were older than or equal to 10 years and met the criteria according to the definition of metabolic syndro
Membrane fouling, in particular biofouling is a major problem in membrane applications for water and wastewater treatment. In this study, cation-exchange membranes were modified with conductive ...polymer polyethyleneimine and nanomaterials such as titanium dioxide (TiO2) and graphene oxide (GO) to improve membrane anti-microbial properties and energy efficiency during electrodialysis. The anti-fouling potential was evaluated by quantitative measurement of biomass and biofilm accumulation on membrane surface with Escherichia coli (E. coli) as model microbes. Experimental results showed polyethyleneimine and nanomaterials coating changed membrane surface hydrophilicity and significantly improved anti-biofouling properties with an optimal nanomaterial dosage of 37.5 μg/mL of coating solution. Polyethyleneimine had limited effect on preventing microbial cell attachment, but demonstrated remarkable anti-biofilm growth by its cytotoxicity. Overall desalination performance of polyethyleneimine coated membrane was similar to unmodified membrane. GO coating significantly improved desalination efficiency because of its high conductivity and negative charge, while TiO2 coated membrane showed decreased overall desalination performance due to its reduced electrical conductivity.
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•Anti-biofouling and energy-efficient cation exchange membranes were developed.•Polyethyleneimine (PEI) reduced biofilm by 67% but not cell attachment.•PEI-TiO2 coating reduced cell attachment and biofilm coverage by 60% and 78%.•PEI-GO coating reduced cell attachment and biofilm coverage by 96% and 98%.•PEI-GO coating significantly enhanced energy efficiency during electrodialysis.
•Nanocomposite cation-exchange membranes were developed for organic fouling control.•The nanocomposite membranes showed superior antifouling and desalination capacity.•All modified membranes did not ...show any acute toxicity towards Vibrio fischeri.
Organic fouling hinders the application of membrane treatment of alternative water. In this study, polyethyleneimine (PEI), titanium dioxide (TiO2) nanoparticles, and graphene oxide (GO) nanosheets were used for modifying cation-exchange membranes to enhance anti-organic fouling and desalination performance during electrodialysis of synthetical water and municipal wastewater. Fouling propensity of the unmodified and modified membranes was quantitatively evaluated by measuring organic accumulation on membrane surface using humic acid (HA, simulating natural organic matter) and bovine serum albumin (BSA, simulating organic matter in municipal wastewater effluent) as model foulants. Significant surface deposition of HA was observed on the unmodified, PEI-TiO2, and PEI-modified membrane surfaces while trivial HA fouling was detected on the PEI-GO membrane. BSA fouling was minor for all the modified membranes compared to the unmodified membrane.
Desalination efficiency of electrodialysis with the modified membranes, except the PEI-modified membrane, was significantly improved in treating synthetical water with HA foulant compared to the electrodialysis with the unmodified membrane (20%~40% reduction of normalized salt removal). Relatively stable desalination behaviors were observed for each membrane system in treating BSA-containing synthetical water, and enhanced desalination was demonstrated with the modified membranes. Subsequent long-term fouling experiments with wastewater effluent revealed the superior antifouling capacity of the nanocomposite membranes (especially for the PEI-GO membrane) over 100-hour operation, while the unmodified membranes exhibited severe fouling (with total more than 60% decline of normalized salt removal) after approximately 50-hour treating wastewater. In a standard Microtox® acute toxicity assay, the nanocomposite membranes did not show any acute toxicity towards Vibrio fischeri due to potential leaching of PEI and nanomaterials, indicating safe utilization of the modified membranes for water treatment.
The highly organized contractile machinery in skeletal and cardiac muscles requires an assembly of myofilament proteins with stringent stoichiometry. To understand the maintenance of myofilament ...protein stoichiometry under dynamic protein synthesis and catabolism in muscle cells, we investigated the equilibrium of troponin I (TnI) in mouse cardiac muscle during developmental isoform switching and in under- and over-expression models. Compared with the course of developmental TnI isoform switching in normal hearts, the postnatal presence of slow skeletal muscle TnI lasted significantly longer in the hearts of cardiac TnI (cTnI) knockout (cTnI-KO) mice, in which the diminished synthesis was compensated by prolonging the life of myofilamental TnI. Transgenic postnatal expression of an N-terminal truncated cTnI (cTnI-ND) using α-myosin heavy chain promoter effectively rescued the lethality of cTnI-KO mice and shortened the postnatal presence of slow TnI in cardiac muscle. cTnI-KO mice rescued with different levels of cTnI-ND over-expression exhibited similar levels of myocardial TnI comparable to that in wild type hearts, demonstrating that excessive synthesis would not increase TnI stoichiometry in the myofilaments. Consistently, haploid under-expression of cTnI in heterozygote cTnI-KO mice was sufficient to sustain the normal level of myocardial cTnI, indicating that cTnI is synthesized in excess in wild type cardiomyocytes. Altogether, these observations suggest that under wide ranges of protein synthesis and turnover, myofilament incorporation determines the stoichiometry of troponin subunits in muscle cells.
Microplastic (MP) pollution is ubiquitous in the terrestrial and marine environments, even in the air. However, ecological risk assessment studies of microplastics are scarce. In the present study, ...an ecological risk assessment model was built to evaluate the risks of microplastics in the Yangtze River Estuary and adjacent marine areas. A basic index database of the impacts of MP pollution on the ecosystem was constructed around three types of indices, namely, the pressure, status, and response indices. While the expert scoring method was used to determine the weights of these indices, in view of the complexity of the ecosystem in the Yangtze River Estuary, the fuzzy comprehensive evaluation method was used to evaluate its ecological risk. According to the model, microplastic pollution in the Yangtze River Estuary and adjacent marine areas was within a lower risk state, indicating that its risks for the marine ecosystem were still within a controllable range.
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•An ecological risk assessment model of microplastics was built.•Index weights for the microplastic pollution risk assessment were set up.•Microplastic pollution was reviewed in the Yangtze River Estuary and adjacent marine areas.•Microplastic pollution was within a lower risk state in the study region.
•The highly dissolved rubber asphalt was prepareed using a compound method of waste engine oil and microwave desulfurization.•The extraction of non-diddolved rubber was utilized to evaluate the ...solubility of rubber asphalt.•The solubility, rheological properties and storage stability of the prepared rubber asphalt were studied.•The highly dissolved rubber asphalt is potentially to improve the performance of rubber asphalt pavement.
Using recycled rubber waste in the construction of asphalt pavements not only improves pavement performance, but also promotes sustainable development. Consequently, rubber asphalt pavements have received significant attention in recent years. However, conventional rubber asphalt has numerous disadvantages such as low solubility, high viscosity, uneven dispersion, and poor storage stability. In this study, a composite method involving waste engine oil addition and microwave desulfurization to prepare highly dissolved rubber asphalt was proposed. Four types of rubber asphalt—conventional rubber asphalt, microwave-treated rubber asphalt, rubber asphalt with added waste engine oil, and highly dissolved rubber asphalt using the proposed composite method—were prepared and tested. The solubility, rheological properties, and storage stability of the prepared rubber asphalt specimens were studied. Specifically, the extraction of undissolved rubber was used to characterize the solubility of rubber asphalt. The results demonstrate that the solubility of the highly dissolved rubber asphalt prepared using the composite method was around 40%, which is 10%–20% higher than that of conventional rubber asphalt. The low-temperature performance and storage stability of the highly dissolved rubber asphalt improved significantly, and it also exhibited good high-temperature performance. The findings obtained herein indicate that the proposed composite treatment method for waste crumb rubber can significantly improve the performance of rubber asphalt, thereby promoting the application of rubber asphalt in the construction of asphalt pavements.
State and local governments consider payment for ecosystem services (PES) a valuable tool for watershed protection. However, regional differences in PES policies, which significantly influence ...province-scale cooperation, have been seldom documented. The interrelationships among these policies directly affect overall PES development in the Yangtze River Economic Belt (YREB). Textual analysis was used to categorize the content of PES policies in 11 provinces from 2004 to 2018. Then, we assessed these PES policies with four indicators (i.e., policy intensity, interdepartmental coordination, diversity, and duration). Finally, we analyzed the impact factors of these regional differences. The results showed that the number of PES policies increased yearly, reaching a peak in 2017. Provinces in the upper reaches had the highest policy-intensity score (7.38), followed by downstream provinces (6.39) and provinces in the middle reaches (4.52). Regarding interdepartmental coordination, the downstream areas exhibited the most interdepartment interaction (27.92%), followed by the upstream areas (20.76%) and the middle areas (19.18%). Diversity in the middle reaches was the highest (scored 4.3) while the upstream area exhibited the lowest diversity value (3.25). Downstream provinces issued PES policies the earliest, with a duration 5.52 years, followed by the upstream provinces (4.68) and middle provinces (4.28). Policy intensity was significantly correlated with fixed-asset investment, solid-waste generation, and population. The results suggest that PES in the YREB needs to be strengthened by enhancing policy consistency. In this regard, identifying regional differences in PES policies can help improve the coordination of PES policies for the whole YREB.
•Text analysis was used to access the implementation of regional PES policies.•Number of PES policies increased yearly in Yangtze River Ecocnomic Belt.•Regional differences were found in policy intensity, coordination and diversity.•Economic level was significantly correlated with policy intensity and diversity.•Identifying PES heterogeneities can help enhance policy coordination of efficiency.
Background
Glucaric acid, one of the aldaric acids, has been declared a “top value-added chemical from biomass”, and is especially important in the food and pharmaceutical industries. Biocatalytic ...production of glucaric acid from glucuronic acid is more environmentally friendly, efficient and economical than chemical synthesis. Uronate dehydrogenases (UDHs) are the key enzymes for the preparation of glucaric acid in this way, but the poor thermostability and low activity of UDH limit its industrial application. Therefore, improving the thermostability and activity of UDH, for example by semi-rational design, is a major research goal.
Results
In the present work, three UDHs were obtained from different
Agrobacterium tumefaciens
strains. The three UDHs have an approximate molecular weight of 32 kDa and all contain typically conserved UDH motifs. All three UDHs showed optimal activity within a pH range of 6.0–8.5 and at a temperature of 30 °C, but the UDH from
A. tumefaciens
(At) LBA4404 had a better catalytic efficiency than the other two UDHs (800 vs 600 and 530 s
−1
mM
−1
). To further boost the catalytic performance of the UDH from AtLBA4404, site-directed mutagenesis based on semi-rational design was carried out. An A39P/H99Y/H234K triple mutant showed a 400-fold improvement in half-life at 59 °C, a 5 °C improvement in
T
50
10
value and a 2.5-fold improvement in specific activity at 30 °C compared to wild-type UDH.
Conclusions
In this study, we successfully obtained a triple mutant (A39P/H99Y/H234K) with simultaneously enhanced activity and thermostability, which provides a novel alternative for the industrial production of glucaric acid from glucuronic acid.
Biocatalysis has found enormous applications in sorts of fields as an alternative to chemical catalysis. In the pursue of green and sustainable chemistry, ionic liquids (ILs) have been considered as ...promising reaction media for biocatalysis, owing to their unique characteristics, such as nonvolatility, inflammability and tunable properties as regards polarity and water miscibility behavior, compared to organic solvents. In recent years, great developments have been achieved in respects to biocatalysis in ILs, especially for preparing various chemicals. This review tends to give illustrative examples with a focus on representative chemicals production by biocatalyst in ILs and elucidate the possible mechanism in such systems. It also discusses how to regulate the catalytic efficiency from several aspects and finally provides an outlook on the opportunities to broaden biocatalysis in ILs.
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