Search

Presented herein is a facile approach, which is easy, cost-effective, environmental benign without any secondary environmental pollution and no requirement for post purification, towards the synthesis of graphene oxides (GOs) with different oxidation degrees by ozone treatment. The synthesized GOs with controlled oxidation degrees can not only increase the quantity of oxygen-containing functional groups on GOs surfaces, but also decrease the sizes of GOs sheets to facilitate their dispersion abilities in aqueous solution, as revealed by characterization. The ozonized GOs were further applied as Co(II) adsorbents from aqueous solutions. The adsorption results showed that this adsorption processes was endothermic and spontaneous, and followed the pseudo-second-order kinetics and the Langmuir adsorption models. The microcosmic mechanism displayed that cobalt can complex with the oxygen-containing functional groups on GOs surfaces. As expected, increased adsorption capacities were observed by GOs with higher oxidation degrees. [ABSTRACT FROM AUTHOR]

ABSTRACT A lactose-containing monomer, N-(2-lactosylethyl)acrylamide, was synthesized and polymerized with N-hydroxyethyl acrylamide and 1 wt % of N, N'-methylenebis(acrylamide) and potassium persulfate as the initiator to produce hydrogels. The weight percent of N-(2-lactosylethyl)acrylamide were increased from 0 to 100% in increments of 10%. Hydrogels were successfully produced with up to 90 wt % of N-(2-lactosylethyl)acrylamide. Gelation was confirmed by inverted vial tests and rheology measurements. The as-prepared hydrogels were used for papain stabilization against heat burden and papain that was loaded into hydrogels showed 45% more activity after heating as compared to papain that was heated without hydrogel stabilization. This hydrogel stabilization technique has potential applications in preserving enzyme activity. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2507-2514 [ABSTRACT FROM AUTHOR]

ABSTRACT Covalently crosslinked polyurethane/urea polymers were synthesized using diamine monomers modified with pendant glucose groups and 2,4-toluene diisocyanate, poly(ethylene glycol) (PEG), and 1,1,1-tris(hydroxymethyl)ethane (triol) comonomers. The polymers showed shape memory behavior with a switching temperature dependent on the glass transition temperature. The glass transition temperature is tuned by varying the mole ratio between the glucose-diamine and PEG used in the polymerization. Increasing PEG content resulted in decreasing glass transition temperature, and a glass transition temperature of 39 °C, close to physiological temperatures, was obtained. The fixed shape showed gradual shape recovery behavior, but a fixity of 70% was achieved when the material was stored at 25 °C. The polymer recovered to the permanent shape when heated to 50 °C. Finally, the surface of a film of the polymer can be sulfated to achieve increased blood-compatibility without sacrificing the shape memory properties. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2252-2257 [ABSTRACT FROM AUTHOR]

Soil saline–alkalization inhibits plant growth and development and seriously affects crop yields. Over their long-term evolution, plants have formed complex stress response systems to maintain species continuity. R2R3-MYB transcription factors are one of the largest transcription factor families in plants, widely involved in plant growth and development, metabolism, and stress response. Quinoa (Chenopodium quinoa Willd.), as a crop with high nutritional value, is tolerant to various biotic and abiotic stress. In this study, we identified 65 R2R3-MYB genes in quinoa, which are divided into 26 subfamilies. In addition, we analyzed the evolutionary relationships, protein physicochemical properties, conserved domains and motifs, gene structure, and cis-regulatory elements of CqR2R3-MYB family members. To investigate the roles of CqR2R3-MYB transcription factors in abiotic stress response, we performed transcriptome analysis to figure out the expression file of CqR2R3-MYB genes under saline–alkali stress. The results indicate that the expression of the six CqMYB2R genes was altered significantly in quinoa leaves that had undergone saline–alkali stress. Subcellular localization and transcriptional activation activity analysis revealed that CqMYB2R09, CqMYB2R16, CqMYB2R25, and CqMYB2R62, whose Arabidopsis homologues are involved in salt stress response, are localized in the nucleus and exhibit transcriptional activation activity. Our study provides basic information and effective clues for further functional investigation of CqR2R3-MYB transcription factors in quinoa. [ABSTRACT FROM AUTHOR]

Background: We documented previously the entity of trichloroethylene (TCE) hypersensitivity syndrome (THS) in occupational workers. Objectives: To identify the culprit causative compound, determine the type of hypersensitivity of THS, and establish a screening test for subjects at risk of THS. Methods: TCE and its main metabolites chloral hydrate (CH), trichloroethanol (TCOH) and trichloroacetic acid (TCA) were used as allergens at different concentrations in skin patch tests. The study included 19 case subjects diagnosed with occupational THS, 22 control healthy workers exposed to TCE (exposure >12 weeks), and 20 validation new workers exposed to TCE for <12 weeks free of THS. All subjects were followed-up for 12 weeks after the patch test. Results: The highest patch test positive rate in subjects with THS was for CH, followed by TCOH, TCA and TCE. The CH patch test positive rate was 100% irrespective of CH concentrations (15%, 10% and 5%). The TCOH patch test positive rate was concentration-dependent (89.5%, 73.7% and 52.6% for 5%, 0.5% and 0.05%, respectively). Lower patch test positive rates were noted for TCA and TCE. All patch tests (including four allergens) were all negative in each of the 22 control subjects. None of the subjects of the validation group had a positive 15% CH patch test. Conclusions: Chloral hydrate seems to be the culprit causative compound of THS and type IV seems to be the major type of hypersensitivity of THS. The CH patch test could be potentially useful for screening workers at risk of THS. [ABSTRACT FROM AUTHOR]

Polyurea-based synthetic glycopolymerscontaining sulfated glucose,mannose, glucosamine, or lactose as pendant groups have been synthesizedby step-growth polymerization of hexamethylene diisocyanate and correspondingsecondary diamines. The obtained polymers were characterized by gelpermeation chromatography, nuclear magnetic resonance spectroscopy,and Fourier transform infrared spectroscopy. The nonsulfated polymersshowed similar results to the commercially available biomaterial polyurethaneTECOFLEX in a platelet adhesion assay. The average degree of sulfationafter reaction with SO3was calculated from elemental analysisand found to be between three and four −OSO3groupsper saccharide. The blood-compatibility of the synthetic polymerswas measured using activated partial thromboplastin time, prothrombintime, thrombin time, anti-IIa, and anti-Xa assays. Activated partialthromboplastin time, prothrombin time, and thrombin time results indicatedthat the mannose and lactose based polymers had the highest anticoagulantactivities among all the sulfated polymers. The mechanism of actionof the polymers appears to be mediated via an anti-IIa pathway ratherthan an anti-Xa pathway. [ABSTRACT FROM AUTHOR]

Saline-alkali stress seriously affects the yield and quality of crops, threatening food security and ecological security. Improving saline-alkali land and increasing effective cultivated land are conducive to sustainable agricultural development. Trehalose, a nonreducing disaccharide, is closely related to plant growth and development and stress response. Trehalose 6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) are key enzymes catalyzing trehalose biosynthesis. To elucidate the effects of long-term saline-alkali stress on trehalose synthesis and metabolism, we conducted an integrated transcriptome and metabolome analysis. As a result, 13 TPS and 11 TPP genes were identified in quinoa (Chenopodium quinoa Willd.) and were named CqTPS1-13 and CqTPP1-11 according to the order of their Gene IDs. Through phylogenetic analysis, the CqTPS family is divided into two classes, and the CqTPP family is divided into three classes. Analyses of physicochemical properties, gene structures, conservative domains and motifs in the proteins, and cis-regulatory elements, as well as evolutionary relationships, indicate that the TPS and TPP family characteristics are highly conserved in quinoa. Transcriptome and metabolome analyses of the sucrose and starch metabolism pathway in leaves undergoing saline-alkali stress indicate that CqTPP and Class II CqTPS genes are involved in the stress response. Moreover, the accumulation of some metabolites and the expression of many regulatory genes in the trehalose biosynthesis pathway changed significantly, suggesting the metabolic process is important for the saline-alkali stress response in quinoa. [ABSTRACT FROM AUTHOR]

ABSTRACT N-alkyl urea peptoid oligomers containing glucose or mannose have been synthesized and characterized. The oligomers were subsequently polymerized using a step-growth polymerization with hexamethylene diisocyanate. Equal moles of both monomers were used to guarantee high-molecular weight polymers. The polymers were characterized by gel permeation chromatography, nuclear magnetic resonance, and Fourier-transform infrared spectroscopy, and contact angle measurements of solvent cast thin films. Sulfation of the final polymers was achieved using a SO3/pyridine complex in pyridine to afford the heparin biomimetics. The average degree of sulfation was calculated to be 3.5 sulfates per saccharide as measured by elemental analysis. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 5230-5238 [ABSTRACT FROM AUTHOR]

ABSTRACT Nitrate is an important nitrogen source used by plants. Despite of the considerable variation in the amount of soil nitrate, plants keep cytosolic nitrate at a homeostatic controlled level. Here we describe a set of homeostatic controller motifs and their interaction that can maintain robust cytosolic nitrate homeostasis at fluctuating external nitrate concentrations and nitrate assimilation levels. The controller motifs are divided into two functional classes termed as inflow and outflow controllers. In the presence of high amounts of environmental nitrate, the function of outflow controllers is associated to efflux mechanisms removing excess of nitrate from the cytosol that is taken up by low-affinity transporter systems (LATS). Inflow controllers on the other hand maintain homeostasis in the presence of a high demand of nitrate by the cell relative to the amount of available environmental nitrate. This is achieved by either remobilizing nitrate from a vacuolar store, or by taking up nitrate by means of high-affinity transporter systems (HATS). By combining inflow and outflow controllers we demonstrate how nitrate uptake, assimilation, storage and efflux are integrated to a regulatory network that maintains cytosolic nitrate homeostasis at changing environmental conditions. [ABSTRACT FROM AUTHOR]

Shape-persistent arylenevinylene macrocycles (AVMs) were successfully prepared in one step from readily available aromatic diene monomers through olefin metathesis in good yields. 1H NMR, UV-Vis absorption and fluorescence studies revealed the aggregation behavior of the obtained macrocycles. SEM characterization showed AVM nanofibril formation. [ABSTRACT FROM AUTHOR]

Introduction: An increasing number of original studies suggested that occupational noise exposure might be associated with the risk of hypertension, but the results remain inconsistent and inconclusive. In addition, the attributable fraction (AF) of occupational noise exposure has not been well quantified. We aimed to conduct a large-scale occupational population-based study to comprehensively investigate the relationship between occupational noise exposure and blood pressure and different hypertension subtypes and to estimate the AF for hypertension burden attributable to occupational noise exposure. Methods: A total of 715,135 workers aged 18–60 years were included in this study based on the Key Occupational Diseases Surveillance Project of Guangdong in 2020. Multiple linear regression was performed to explore the relationships of occupational noise exposure status, the combination of occupational noise exposure and binaural high frequency threshold on average (BHFTA) with systolic and diastolic blood pressure (SBP, DBP). Multivariable logistic regression was used to examine the relationshipassociation between occupational noise exposure status, occupational noise exposure combined with BHFTA and hypertension. Furthermore, the attributable risk (AR) was calculated to estimate the hypertension burden attributed to occupational exposure to noise. Results: The prevalence of hypertension among occupational noise-exposed participants was 13·7%. SBP and DBP were both significantly associated with the occupational noise exposure status and classification of occupational noise exposure combined with BHFTA in the crude and adjusted models (all P < 0·0001). Compared with workers without occupational noise exposure, the risk of hypertension was 50% greater among those exposed to occupational noise in the adjusted model (95% CI 1·42–1·58). For participants of occupational noise exposed with BHFTA normal, and occupational noise exposed with BHFTA elevated, the corresponding risks of hypertension were 48% (1·41–1·56) and 56% (1·46–1·63) greater than those of occupational noise non-exposed with BHFTA normal, respectively. A similar association was found in isolated systolic hypertension (ISH) and prehypertension. Subgroup analysis by sex and age showed that the positive associations between occupational noise exposure and hypertension remained statistically significant across all subgroups (all P < 0.001). Significant interactions between occupational noise status, classification of occupational noise exposure combined with BHFTA, and age in relation to hypertension risk were identified (all P for interaction < 0.001). The associations of occupational noise status, classification of occupational noise exposure combined with BHFTA and hypertension were most pronounced in the 18–29 age groups. The AR% of occupational noise exposure for hypertension was 28·05% in the final adjusted model. Conclusions: Occupational noise exposure was positively associated with blood pressure levels and the prevalence of hypertension, ISH, and prehypertension in a large occupational population-based study. A significantly increased risk of hypertension was found even in individuals with normal BHFTA exposed to occupational noise, with a further elevated risk observed in those with elevated BHFTA. Our findings provide epidemiological evidence for key groups associated with occupational noise exposure and hypertension, and more than one-fourth of hypertension cases would have been prevented by avoiding occupational noise exposure. [ABSTRACT FROM AUTHOR]

Lead (Pb) exposure is well recognized as a significant environmental factor associated with the high incidence of cardiovascular diseases. However, the carriers and molecular targets of Pb in human blood remain to be understood, especially for a real Pb exposure scenario. In this study, a total of 350 blood samples were collected from the smelting workers and systematically analyzed using metallomics and metalloproteomics approaches. The results showed that the majority of Pb (∼99.4%) could be presented in the blood cells. Pb in the cytoplasm of blood cells accounted for approximately 83.1% of the total blood Pb, with nearly half of Pb being bound to proteins. Pb-binding proteins in the blood of workers were identified as hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. Multiple linear regression analysis demonstrated that higher levels of Pb bound to proteins (Mix-bound Pb and Protein-bound Pb) were positively associated with higher systolic blood pressure (p < 0.05). However, the association between blood lead level, Pb levels in the blood cells and systolic blood pressure was not observed (p > 0.05). This study suggested that Pb bound to proteins could be a suitable biomarker for indicating the potential risk of occupational hypertension. [Display omitted] • 99.4% of Pb was concentrated in blood cells of workers, and primarily (83.1%) existed in cytoplasm, the distribution patterns of Pb in the blood was affected by workplaces. • Pb selectively bound to proteins in blood cells of workers, including hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. • Protein-bound Pb is an earlier and more sensitive indicator than blood lead levels, as it is positively correlated with systolic blood pressure, indicating the risk of hypertension. [ABSTRACT FROM AUTHOR]

The increased production of carbon dots (CDs) and the release and accumulation of CDs in both surface and groundwater has resulted in the increasing interest in their research. To assess the environmental behavior of CDs, the interaction between CDs and goethite was studied under different environmental conditions. Electrokinetic characterization of CDs suggested that the ?-potential and size distribution of CDs were affected by pH and electrolyte species, indicating that these factors influenced the stability of CDs in aqueous solutions. Traditional Derjaguin-Landau-Verwey-Overbeek theory did not fit well the aggregation process of CDs. Results of the effects of pH and ionic strength suggested that electronic attraction dominated the aggregation of CDs. Compared with other minerals, hydrogen-bonding interactions and Lewis acid-base interactions contributed to the aggregation of CDs, in addition to van der Waals and electrical double-layer forces. Adsorption isotherms and microscopic Fourier transformed infrared spectroscopy indicated that chemical bonds were formed between CDs and goethite. These findings are useful to understand the interaction of CDs with minerals, as well as the potential fate and toxicity of CDs in the natural environment, especially in soils and sediments. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) is an ideal adsorbent due to excellent physicochemical properties. Humic acid (HA) is ubiquitous in aquatic and soil environment, which can affect the migration of metal ions. In this study, we investigated the sorption mechanisms of U(VI) onto GO surfaces in the presence of HA. pH dependent and ionic strength independent sorption process were observed and the concentration of HA is positively proportional to U(VI) sorption capacities. Results also suggest that a pre-mixing HA + U(VI) gave better results than a pre-mixing of GO + HA, which can be explained by the size distribution of different GO systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Atmospheric environmental issues in workplaces should be taken seriously. • Evidence is scarce on the interaction between environmental and occupational factors. • We conducted a cross-sectional study among 363,788 workers in south China in 2020. • PM 2.5 and its components were positively associated with an increased risk of OVD. • Less-dust workers and those exposed to occupational noise and heat were more susceptible. The new round of WHO/ILO Joint Estimates of the Work-related Burden of Disease assessment requires futher research to provide more evidence, especially on the health impact of ambient air pollution around the workplace. However, the evidence linking obstructive ventilatory dysfunction (OVD) to fine particulate matter (PM 2.5) and its chemical components in workers is very limited. Evidence is even more scarce on the interactive effects between occupational factors and particle exposures. We aimed to fill these gaps based on a large ventilatory function examination of workers in southern China. We conducted a cross-sectional study among 363,788 workers in southern China in 2020. The annual average concentration of PM 2.5 and its components were evaluated around the workplace through validated spatiotemporal models. We used mixed-effect models to evaluate the risk of OVD related to PM 2.5 and its components. Results were further stratified by basic characteristics and occupational factors. Among the 305,022 workers, 119,936 were observed with OVD. We found for each interquartile range (IQR) increase in PM 2.5 concentration, the risk of OVD increased by 27.8 (95 % confidence interval (CI): 26.5–29.2 %). The estimates were 10.9 % (95 % CI : 9.7–12.1 %), 15.8 % (95 % CI : 14.5–17.2 %), 2.6 % (95 % CI : 1.4–3.8 %), 17.1 % (95 % CI : 15.9–18.4 %), and 11 % (95 % CI : 9.9–12.2 %), respectively, for each IQR increment in sulfate, nitrate, ammonium salt, organic matter and black carbon. We observed greater effect estimates among females, younger workers, workers with a length of service of 24–45 months, and professional skill workers. Furthermore, it is particularly noteworthy that the noise-exposed workers, high-temperature-exposed workers, and less-dust-exposed workers were at a 5.7–68.2 % greater risk than others. PM 2.5 and its components were significantly associated with an increased risk of OVD, with stronger links among certain vulnerable subgroups. [ABSTRACT FROM AUTHOR]

MP2/6-31+G(d,p)//MP2/6-31G(d) method was employed to investigate the pyrolyses of O-sec-butyl S-methyl xanthate (Chugeav reaction) and S-sec-butyl O-methyl xanthate, which gave regioselective products of E-butene, Z-butene and 1-butene. Both procedures were found to have 13 possible pathways, of which nine pathways would generate the alkene products. For O-sec-butyl S-methyl xanthate, the computational results indicated that the most favorable three pathways corresponded to a two-step mechanism, with the rate-determining step to be a thion sulfur atom involved six-membered ring transition states. The calculated products distribution was consistent with the experimental observations. However, for S-sec-butyl O-methyl xanthate, thiol-participated four-membered ring transition states were found to be more energetically favored than the six-membered ring transition state to produce 1-butene, which can be attributed to a larger sulfur atomic size than an oxygen atom. As the calculation result, only trace amount of 1-butene could be obtained with a major product being E-butene and Z-butene as a minority. [ABSTRACT FROM AUTHOR]

Silicosis is a severe occupational lung disease caused by inhalation of silica particles. Unfortunately, there are currently limited treatment options available for silicosis. Recent advances have indicated that bone marrow mesenchymal stem cells (BMSCs) have a therapeutic effect on silicosis, but their efficacy and underlying mechanisms remain largely unknown. In this study, we focused on the early phase of silica-induced lung injury to investigate the therapeutic effect of BMSCs. Our findings demonstrated that BMSCs attenuated silica-induced acute pulmonary inflammation by inhibiting NLRP3 inflammasome pathways in lung macrophages. To further understand the mechanisms involved, we utilized RNA sequencing to analyze the transcriptomes of BMSCs co-cultured with silica-stimulated bone marrow-derived macrophages (BMDMs). The results clued tumor necrosis factor-stimulated gene 6 (TSG-6) might be a potentially key paracrine secretion factor released from BMSCs, which exerts a protective effect. Furthermore, the anti-inflammatory and inflammasome pathway inhibition effects of BMSCs were attenuated when TSG-6 expression was silenced, both in vivo and in vitro. Additionally, treatment with exogenous recombinant mouse TSG-6 (rmTSG-6) demonstrated similar effects to BMSCs in attenuating silica-induced inflammation. Overall, our findings suggested that BMSCs can regulate the activation of inflammasome in macrophages by secreting TSG-6, thereby protecting against silica-induced acute pulmonary inflammation both in vivo and in vitro. • TSG-6 is one of the key compounds secreted by BMSCs in response to silica-induced inflammation. • TSG-6 attenuates silica-induced acute pulmonary inflammation both in vivo and in vitro. • TSG-6 inhibits NLRP3 inflammasome signaling pathway of silica-stimulated macrophages [ABSTRACT FROM AUTHOR]

Shape-persistent arylenevinylene macrocycles (AVMs) were successfully prepared in one step from readily available aromatic diene monomers through olefin metathesis in good yields. 1H NMR, UV-Vis absorption and fluorescence studies revealed the aggregation behavior of the obtained macrocycles. SEM characterization showed AVM nanofibril formation. [ABSTRACT FROM AUTHOR]

Objectives: The objective of our study was to evaluate the association between occupational exposure to trichloroethylene (TCE), a suspected lymphomagen, and serum levels of miRNAs in a cross-sectional molecular epidemiology study of TCE-exposed workers and comparable unexposed controls in China. Methods: Serum levels of 40 miRNAs were compared in 74 workers exposed to TCE (median: 12 ppm) and 90 unexposed control workers. Linear regression models were used to test for differences in serum miRNA levels between exposed and unexposed workers and to evaluate exposure–response relationships across TCE exposure categories using a three-level ordinal variable [i.e., unexposed, < 12 ppm, the median value among workers exposed to TCE) and ≥ 12 ppm)]. Models were adjusted for sex, age, current smoking, current alcohol use, and recent infection. Results: Seven miRNAs showed significant differences between exposed and unexposed workers at FDR (false discovery rate) < 0.20. miR-150-5p and let-7b-5p also showed significant inverse exposure–response associations with TCE exposure (Ptrend= 0.002 and 0.03, respectively). The % differences in serum levels of miR-150-5p relative to unexposed controls were − 13% and − 20% among workers exposed to < 12 ppm and ≥ 12 ppm TCE, respectively. Conclusions: miR-150-5p is involved in B cell receptor pathways and let-7b-5p plays a role in the innate immune response processes that are potentially important in the etiology of non-Hodgkin lymphoma (NHL). Further studies are needed to replicate these findings and to directly test the association between serum levels of these miRNAs and risk of NHL in prospective studies. [ABSTRACT FROM AUTHOR]

Natural bacterial isolates from heavily contaminated sites may evolve diverse tolerance strategies, including biosorption, efflux mechanism, and intracellular precipitation under the continually increased stress of toxic lead (Pb) from anthropogenic activities. These strategies utilize a large variety of functional groups in biological macromolecules (e.g., exopolysaccharides (EPSs) and metalloproteins) and inorganic ligands, including carboxyl, phosphate and amide groups, for capturing Pb. The amount and type of binding sites carried by biologically originated materials essentially determines their performance and potential for Pb removal and remediation. Many factors, e.g., metal ion radius, electronegativity, the shape of the cell surface sheath, temperature and pH, are thought to exert significant influences on the abovementioned interactions with Pb. Conclusively, understanding the chemical basis of Pb-binding in these bacteria can allow for the development of effective microbial Pb remediation technologies and further elucidation of Pb cycling in the environment. Unlabelled Image [ABSTRACT FROM AUTHOR]

• 2D MOFs nano-sheets were successfully prepared in a one-step and cost-effective synthetic route. • The solvent ratios have a great effect on their structural morphologies. • The Qmax of 2D MOFs nano-sheets can be as high as 591.79 mg g−1 for U(VI) immobilization. • The U(VI) immobilization process is exothermic and spontaneous. • The U(VI) immobilization mechanism is proposed via the binding interactions between U(VI) and −OH/C–N(H) groups. In this study, a new kind of thin 2D MOFs nano-sheets (MNS) was successfully prepared through complexation between 2-methylimidazole and Cu(II) by a one-step, and cost-effective route. The structural morphologies can be tuned by adjusting the ratio of MeOH/H 2 O. The synthesized MNS (MNS-1, MNS-2, MNS-3 and MNS-4) were fully characterized and the results indicated that the synthesized MNS were freestanding and possess micro-sized lateral dimensions and nanoscale thickness of sub-25 nm. All the obtained MNS display great performance with the adsorption capacity hierarchy of MNS-2 (591.79 mg·g-1) > MNS-3 (409.49 mg·g−1) > MNS-4 (387.07 mg·g−1) > MNS-1 (384.84 mg·g−1) at pH ˜ 6.0, and 298 K. The thermodynamic parameters indicated the exothermic and spontaneous nature of U(VI) immobilization. The U(VI) immobilization mechanism was achieved through the complexation between U(VI) and C–N(H) /−OH groups. This work supplies a facile and purposeful approach for developing 2D MOFs nano-sheets toward a highly efficient immobilization of U(VI), and it also promotes the preparation of structure-based design of nanomaterials for radionuclide-containing-medium pretreatment. [ABSTRACT FROM AUTHOR]

Abstract: N‐alkylation of fulleropyrrolidines in the presence of polyformaldehyde and p‐toluenesulfonic acid was systematically investigated. With the addition of ketones/arylboronic acids, a series of novel N‐alkyl fulleropyrrolidines were formed. Nevertheless, in the absence of ketones/arylboronic acids, scarce N‐methyl fulleropyrrolidines were obtained with the aid of benzyl alcohol. Possible reaction pathways for the formation of N‐alkyl fulleropyrrolidines were proposed to elucidate the above reaction process. [ABSTRACT FROM AUTHOR]

The magnesium perchlorate-mediated reaction of [60]fullerene with aldehydes and triethylamine under air conditions afforded a series of rare cyclopentafullerenes in moderate to good yields with high stereoselectivity. A plausible reaction mechanism was suggested to elucidate the formation of cyclopentafullerenes. [ABSTRACT FROM AUTHOR]

Metal silicates have attracted extensive interests due to their unique structure and promising properties in adsorption and catalysis. However, their applications were hampered by the complex and expensive synthesis. In this paper, three-dimensional (3D) hierarchical flower-like metal silicate, including magnesium silicate, zinc silicate, nickel silicate and cobalt silicate, were for the first time prepared by using rice husks as a sustainable silicon source. The flower-like morphology, interconnected ultrathin nanosheets structure and high specific surface area endowed them with versatile applications. Magnesium silicate was used as an adsorbent with the maximum adsorption capacities of 557.9, 381.3, and 482.8 mg/g for Pb 2+ , tetracycline (TC), and UO 2 2+ , respectively. Ni nanoparticles/silica (Ni NPs/SiO 2 ) exhibited high catalytic activity and good stability for 4-nitrophenol (4-NP) reduction within only ∼160 s, which can be attributed to the ultra-small particle size (∼6.8 nm), good dispersion and high loading capacity of Ni NPs. Considering the abundance and renewability of rice husks, metal silicate with complex architecture can be easily produced at a large scale and become a sustainable and reliable resource for multifunctional applications. [ABSTRACT FROM AUTHOR]

Carbonaceous nanofibers (CNFs) were synthesized by a hydrothermal carbonization method and characterized by microstructure characterization methods (SEM, TEM, XPS, FTIR) and potentiometric titration. The effect of the environmental facts on the adsorption of Eu(III) on CNFs were examined by the batch experiments. The maximum adsorption capacity of Eu(III) on CNFs was calculated to be 62.6 mg ∙ g − 1 at pH 4.5 and 288 K. The thermodynamic parameters from Eu(III) adsorption isotherms at three temperatures suggested that this adsorption process was both spontaneous and endothermic. The CNFs/Eu(III) interactions were investigated by using diffuse layer modeling. The combination of a predominated XOEu(OH) + complex at pH < 3.5 and XOEu(OH) + and SOEu(OH) 2 complex at pH > 3.5 was consistent with the experiment data. CNFs can be regarded as a promising environmental functional nanomaterial for the removal of lanthanides from radionuclide contaminated water. [ABSTRACT FROM AUTHOR]

An organic–inorganic polypyrrole/titanium(IV) biphosphate hybrid, PPy/Ti(HPO 4 ) 2 , was successfully synthesized by oxidative polymerization and applied to remove Cr(VI) from aqueous solutions. The as-prepared organic–inorganic hybrid was characterized by scanning electron microscope, X-ray diffraction, zeta potential analysis and X-ray photoelectron spectroscopy. The adsorption conditions, such as contact time, pH value and ionic strength, were investigated, indicating a pH and ionic strength dependent adsorption process. The adsorption kinetics fitted well with the pseudo-second-order kinetic model and the equilibrium data can be described by the Langmuir isotherm with a maximum adsorption capacity of 1.67 mmol/g at pH = 3.5 ± 0.1 and T = 288.15 K. Thermodynamic parameters calculated from the temperature-dependent adsorption isotherms suggested that the adsorption of Cr(VI) on PPy/Ti(HPO 4 ) 2 hybrid was an endothermic and spontaneous process. These results suggested that the PPy/Ti(HPO 4 ) 2 hybrid might be a potential candidate for the separation of Cr(VI) from aqueous solution. [ABSTRACT FROM AUTHOR]

Highlights: [•] Amidoxime-functionalized silica coated Fe3O4 was synthesized and characterized. [•] Fe3O4@SiO2-AO exhibited fast and efficient sorption for U(VI). [•] Fe3O4@SiO2-AO could be easily separated from aqueous solutions with a magnet. [•] Fe3O4@SiO2-AO was resistant to acid corrosion. [•] U(VI)-loaded Fe3O4@SiO2-AO could be efficiently regenerated and reused. [Copyright &y& Elsevier]

Bacterial degradation is unequivocally considered as an important way for the cleanup of polycyclic aromatic hydrocarbon (PAHs) in the aquatic environment. However, the diversity and distribution of PAH-degrading bacterial communities and PAH degradation-related genes (PAHDGs) in ambient environment need to be investigated. In this study, bacteria in the water of the Pearl River Estuary (PRE) were initially separated as the particle-attached bacteria (PAB) and free-living bacteria (FLB), and were further characterized using metagenomic approaches. Proteobacteria (80.1 %) was identified as the most abundant PAH-degrading phylum in the PRE water, followed by Bacteroidetes, Actinobacteria, and Firmicutes. A substantial difference in the community structure was observed between PAH-degrading PAB and FLB. Both of PAH-degrading bacteria and PAHDGs were enriched on the suspended particulate matters (SPMs), with the range of enrichment factor (EF) from 7.84 × 104 to 6.64 × 106 (PAH-degrading bacteria) and from 1.14 × 103 to 1.76 × 105 (PAHDGs). The levels of PAH-degrading bacteria 16 S rRNA genes and PAHDGs on the SPMs were both significantly correlated with those in the aqueous phase (AP) in the PRE water (p < 0.05), indicating a dynamic distribution of PAH-degrading bacteria between these two phases. The total PAH concentrations on the SPMs of the PRE water were also significantly correlated with the total PAHDG levels in the PAB (p < 0.05). Our results suggested that the SPMs could be the important compartment for the elimination of PAHs from the aquatic environment. • Proteobacteria was identified as the most abundant PAH-degrading phylum in the PRE. • PAH-degrading bacteria were enriched on the suspended particulate matters (SPMs). • There was a dynamic equilibrium of PAH-degrading bacteria between the SPMs and AP. • SPMs were the main location for bacterial degradation of PAHs in aquatic environment. [ABSTRACT FROM AUTHOR]

• Occupational exposures were associated with DNA methylation aging biomarkers. • Benzene and trichloroethylene exposures increased epigenetic age acceleration. • Epigenetic aging biomarkers capture impacts of environmental chemicals on health. Epigenetic aging biomarkers are associated with increased morbidity and mortality. We evaluated if occupational exposure to three established chemical carcinogens is associated with acceleration of epigenetic aging. We studied workers in China occupationally exposed to benzene, trichloroethylene (TCE) or formaldehyde by measuring personal air exposures prior to blood collection. Unexposed controls matched by age and sex were selected from nearby factories. We measured leukocyte DNA methylation (DNAm) in peripheral white blood cells using the Infinium HumanMethylation450 BeadChip to calculate five epigenetic aging clocks and DNAmTL, a biomarker associated with leukocyte telomere length and cell replication. We tested associations between exposure intensity and epigenetic age acceleration (EAA), defined as the residuals of regressing the DNAm aging biomarker on chronological age, matching factors and potential confounders. Median differences in EAA between exposure groups were tested using a permutation test with exact p -values. Epigenetic clocks were strongly correlated with age (Spearman r > 0.8) in all three occupational studies. There was a positive exposure-response relationship between benzene and the Skin-Blood Clock EAA biomarker: median EAA was −0.91 years in controls (n = 44), 0.78 years in workers exposed to <10 ppm (n = 41; mean benzene = 1.35 ppm; p = 0.034 vs. controls), and 2.10 years in workers exposed to ≥10 ppm (n = 9; mean benzene = 27.3 ppm; p = 0.019 vs. controls; p trend = 0.0021). In the TCE study, control workers had a median Skin-Blood Clock EAA of −0.54 years (n = 71) compared to 1.63 years among workers exposed to <10 ppm of TCE (n = 27; mean TCE = 4.22 ppm; p = 0.035). We observed no evidence of EAA associations with formaldehyde exposure (39 controls, 31 exposed). Occupational benzene and TCE exposure were associated with increased epigenetic age acceleration measured by the Skin-Blood Clock. For TCE, there was some evidence of epigenetic age acceleration for lower exposures compared to controls. Our results suggest that some chemical carcinogens may accelerate epigenetic aging. [ABSTRACT FROM AUTHOR]

Fish consumption is one of the major ways through which humans receive exposure to mercury (Hg). The existing forms of Hg in food, particularly Hg bound to proteins, may affect the absorption of Hg by humans and subsequently its potentially toxic effects. However, the knowledge regarding Hg-binding proteins in edible fish muscle is scarce. In the present study, salmon and tuna fish muscles, collected from seven different regions and countries, were analyzed using metallomics- and proteomics-based techniques. The concentration of Hg in sashimi samples ranged from 4.4 to 317.4 ng/g. Size exclusion chromatography (SEC) coupled with inductively coupled plasma mass spectrometer (ICP-MS) showed that beta-actin was a novel Hg-binding protein from the fish muscles, and this protein could also bind bismuth (Bi), silver (Ag), and copper (Cu). Hg bound to beta-actin accounted for approximately 30.2–37.6% of the total Hg in the tuna muscles and was significantly correlated to total Hg in the fish muscles (r = 0.98, p < 0.01) and in the fraction of soluble proteins (r = 0.94, p < 0.01). These findings suggest that proteins act as the main Hg accumulation sites in edible fish; thus, increasing human exposure to Hg following gastrointestinal digestion. • More than half of Hg was deposited in the soluble protein fraction of fish muscle. • Beta-actin was identified as a novel Hg-binding protein in the fish muscle. • More than 30% of the total Hg in tuna muscle was bound to beta-actin. [ABSTRACT FROM AUTHOR]

Gadolinium-based contrast agents (GBCAs), frequently applied in clinical diagnosis, may cause nephrogenic systemic fibrosis (NSF) probably due to the gadolinium ion (Gd3+) released from the GBCAs. However, Gd-binding proteins and related mechanism responsible for Gd toxicity remained to be understood. In this study, NIH-3T3 cells were chosen as a model for Gd exposure assays and identification of Gd-binding proteins. A comparative assay showed that gadolinium chloride (GdCl 3) was much more toxic than gadolinium diamide (Gd-DTPA-BMA, a GBCAs). Majority of Gd were absorbed by cells and existed in the fractions of the cell fragment and soluble proteins. High performance liquid chromatography-inductively coupled plasma mass spectrometry(HPLC-ICP-MS), polyacrylamide gel electrophoresis (SDS PAGE) and liquid chromatography-triple time of flight mass spectrometry (LC-Triple TOF) were employed for the identification and characterization of potential Gd-binging proteins. Tubulin was identified as a novel Gd-binding protein in the NIH-3T3 cells. The binding of Gd to tubulin might inhibit assembling of tubulin or depolymerize microtubules in cells. Our results suggested that the formation of microtubules interfered by binding of free Gd3+ to tubulin could be an important molecular mechanism of Gd toxicity. Image 1 • Gadolinium chloride (GdCl 3) was much more toxic than gadolinium diamide (Gd-DTPA-BMA) to NIH-3T3 cells. • HPLC-ICP-MS, SDS PAGE, LC-Triple TOF were employed for identification and characterization of potential Gd-bining proteins. • Tubulin was identified as a novel Gd-binding protein in the NIH-3T3 cells. • Binding of Gd to tubulin might inhibit assembling of tubulin or depolymerize microtubules, which causing the cytotoxicity. [ABSTRACT FROM AUTHOR]