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Amine acid transformation is an important chemical process in biological systems. As a well-developed and acknowledged tool, chiral aldehyde catalysis provides good catalytic activation and stereoselective control abilities in the asymmetric reaction of N-unprotected amino acid esters and amino acid esters analogs, in which the key to success is the design of the catalysts derived from chiral BINOL aldehyde, which is based on the face control of enolate intermediates. In this review, one of the co-catalytic systems that combined with a transition metal to form a multiplex catalytic system and the well-established multiplex stereocenters of chiral aldehyde catalysis have been reviewed. Finally, a novel organocatalysis is prospected.

Objective. To study the effect of liraglutide on the thickness of epicardial adipose tissue (EAT) in type 2 diabetes mellitus (T2DM) patients with abdominal obesity. Methods. Abdominal obesity T2DM patients with poor glycemic control were collected and treated with liraglutide. The changes of blood glucose, blood lipid, waist circumference, body mass index (BMI), and EAT thickness were compared after 3 months of treatment with liraglutide. Cardiac magnetic resonance imaging (MRI) was used to measure EAT thickness. Results. After 3 months of treatment with liraglutide, glycosylated hemoglobin (HbA1c) decreased from 9.81 ± 1.46 % to 6.94 ± 1.29 % ( 95 % CI = 2.14 – 3.59 , p < 0.001 ). The weight decreased from 91.67 ± 16.29 kg to 87.29 ± 16.43 kg ( 95 % CI = 2.97 – 5.79 , p < 0.001 ). Waist circumference before treatment was 103.69 ± 9.14 cm, and after treatment was 96.42 ± 8.42 cm ( 95 % CI = 5.04 – 9.50 , p < 0.001 ). Total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were significantly lower than those before treatment. TC decreased from 5.34 ± 1.05 mmol/L to 4.86 ± 0.97 mmol/L ( 95 % CI = 0.15 – 0.82 , p < 0.001 ). TG was 1.89 (1.48-3.17) and then to 1.92 ± 0.69 ( p = 0.03 ). LDL-C decreased from 3.39 ± 0.84 mmol/L to 3.01 ± 0.74 mmol/L ( 95 % CI = 0.17 – 0.59 , p = 0.001 ). HDL-C increased by 1.7% after treatment, with no significant difference ( p = 0.062 ). More importantly, the thickness of EAT decreased from 5.0 (5.0-7.0) mm to 3.95 ± 1.43 mm ( p < 0.001 ) after liraglutide administered for 3 months. Conclusion. Liraglutide significantly reduces EAT thickness in T2DM with abdominal obesity, which provides theoretical support for the cardiovascular benefits of liraglutide.

To investigate the effect of multifactorial intervention on the urinary albumin to creatinine ratio (UACR) and the estimated glomerular filtration rate (eGFR) in short-duration type 2 diabetes.A total of 150 type 2 diabetes patients, with disease duration1 year and with no evidence of atherosclerosis were randomized to either the intensive intervention group (IG, n = 75), or the conventional group (CG, n = 75) for 7 years. The predefined endpoint of microvascular complications was the progression of renal impairments (the development of albuminuria and the change of eGFR).The incidence of progression to albuminuria (UACR ≥30 mg/g) was 12% in IG and 28% in CG (HR 0.37, 95% CI: 0.19-0.70, P = .0025). eGFR was significantly lower in IG than that in CG in the year 2 (P = .043) and 3 (P = .032) follow-up. Sex, fasting plasma glucose (FPG), HbA1c, and systolic blood pressure (SBP) were independently associated with the UACR (β = -5.112, P = .015; β = 0.908, P = .045; β = 2.087, P = .038; and β = 2.787, P = .002, respectively); aging was independently associated with eGFR (β = -0.447, P = .000).Intensive multifactorial intervention delayed the progression to albuminuria, and reduced eGFR rapidly in early stage of intervention in short-duration type 2 diabetes. FPG, HbA1c, and SBP were risk factors for UACR increase; aging was a risk factor for eGFR decline.

Carboxymethyl chitosan (CMCS), acrylamide, and methacryloxyethyltrimethyl ammonium chloride were used as co-monomers to produce a sludge dewatering agent carboxymethyl chitosan-graft-poly(acrylamide-methacryloxyethyltrimethyl ammonium chloride) (CCPAD) by UV-induced graft polymerization. Single-factor experiments and response surface methodology were employed to investigate and optimize the grafting rate, grafting efficiency, and intrinsic viscosity influenced by the total monomer concentration, CMCS concentration, cationic degree, pH value, and illumination time. The structure, surface morphology, and thermal stability of CCPAD were characterized by infrared spectroscopy, hydrogen nuclear magnetic resonance, X-ray diffraction, scanning electron microscopy, and differential thermal-thermogravimetry. The raw sludge with 97.9% water content was sourced from the concentrated tank of a sewage treatment plant and used in the sludge condition experiments. In addition, CCPAD was applied as the sludge conditioner to investigate the effects of cationic degree, intrinsic viscosity, and pH on the supernatant turbidity, moisture content, specific resistance to filtration, and sludge settling ratio. Moreover, the mechanism of sludge conditioning by CCPAD was discussed by examining the zeta potential and extracellular polymeric substance (EPS) content of the supernatant. The sludge dewatering results confirmed that CCPAD had excellent performance for improving sludge dewaterability.

Vanadium and chromium co-exist commonly with elevated levels in groundwater at vanadium smelting sites. While bioremediation has been recognized promising for this co-contamination treatment in aquifer, interactions during vanadium (V) [V(V)] and chromium (VI) [Cr(VI)] bio-reductions under autotrophic condition remain largely unknown. In this study, efficient reductions of V(V) and Cr(VI) from synthetic groundwater were realized simultaneously in a continuous flow autotrophic sulfur-based biosystem, with more than 85% overall removals under hydrochemical and hydrodynamic fluctuations during 276-d operation. Soluble Cr(VI) was reduced to insoluble Cr(III) preferentially, while reduction of soluble V(V) to insoluble V(IV) was easily inhibited. Elemental sulfur [S(0)] was bio-oxidized to sulfate. Analyses of carbon isotope, microbial community and metabolic pathway revealed the synergetic mechanisms. Autotrophs (e.g., Sulfuricurvum) utilized energy released from S(0) oxidation to synthesize volatile fatty acids (VFAs), which were consumed by heterotrophic V(V) and/or Cr(VI) reducers (e.g., Geobacter). Functional genes responsible for S(0) oxidation and reduction of V(V) and Cr(VI) were detected. V(V) and Cr(VI) reductions were catalyzed by both cytochrome c and nicotinamide adenine dinucleotide. VFAs were also transformed to glycogen in cells to store energy. Robust remediation strategy is thereby proposed for aquifer co-contaminated by V(V) and Cr(VI).

Silicalite-1 (S-1) zeolite membrane synthesized by seed method with superior features attracts intensive attentions, while the influences of key parameters during synthesis process and its applications for organics removal require further investigation. This study revealed the morphology and the structure of the prepared membranes under different crystallization temperatures and seed concentrations by using a suite of characterization methods. The as-prepared membrane under optimal condition (crystallization temperature of 175 °C and seed concentration of 1.0 wt. %) possessed high membrane integrity, with ideal separation factor of 4.0. It also exhibited outstanding performance for organics removal, with dyes retention of 99.9% and 99.2% for 500 mg L−1 neutral red and 500 mg L−1 methyl blue, respectively. Excellent antifouling property of the synthesized membrane was also proved. Results of this work can guide the characteristic improvement of the S-1 zeolite membrane by adjusting key parameters and broaden its applications in dye wastewater treatment.

Adsorption is recognized as one of the most efficient approaches for antibiotics removal from water. Inspired by the enzyme-substrate interaction model, we proposed induced-fit adsorption (IFA) model, and rationally designed and fabricated diol-based porous organic polymers (POPs) as adsorbents for tetracycline (TC) removal. For 2,3-naphthalenediol-based POP (NTdiol-POP), the preferable geometry of diol-groups contributed to the high binding energy with TC species and flexible methylene linkages between neighboring rigid naphthalene rings gave rise to precisely matching between TC species and adsorbents, that is, the induced-fit conformation change. As a result, NTdiol-POP exhibited a high saturated adsorption capacity of 155.8 mg g−1. More importantly, NTdiol-POP exhibited excellent TC removal efficiencies in both concentrated solution (96% for 4 p.p.m) and trace level solution (97% for 250 p.p.b).

Bioelectricity generated from the microbial fuel cell (MFC) is applied to the bioelectrical reactor (BER) directly to enhance microbial reduction of vanadium (V) (V(V)) in groundwater. With the maximum power density of 543.4 mW m −2 from the MFC, V(V) removal is accelerated with efficiency of 93.6% during 12 h operation. Higher applied voltage can facilitate this process. V(V) removals decrease with the increase of initial V(V) concentration, while extra addition of chemical oxygen demand (COD) has little effect on performance improvement. Microbial V(V) reduction is enhanced and then suppressed with the increase of conductivity. High-throughput 16S rRNA gene pyrosequencing analysis implies the accumulated Enterobacter and Lactococcus reduce V(V) with products from fermentative microorganisms such as Macellibacteroides . The presentation of electrochemically active bacteria as Enterobacter promotes electron transfers. This study indicates that application of bioelectricity from MFCs is a promising strategy to improve the efficiency of in-situ bioremediation of V(V) polluted groundwater.

We present here a novel, low cost and environmental-friendly synthetic strategy for fabricating flowerlike magnetic mesoporous carbon (MMC) microspheres by using silica coated Fe3O4 as core, anisotropic layered double hydroxide (LDH) nanocrystals as hard template and dopamine as carbon source, respectively. The resulting MMC spheres has high surface areas (90.3 m(2) g(-1)), excellent magnetic response (16.99 emu g(-1)), and large mesopore volume (0.22 cm(3) g(-1)), as well as good chemical inertness and mechanical stability. The MMC spheres were used to adsorb 2,4,6-trichlorophenol (TCP) from simulated water samples. Experiment results suggest that the adsorption was favorable at acidic pH and increased with the rise of initial TCP concentration and temperature. Kinetic parameters were proved to follow the pseudo-second-order kinetics model and the equilibrium data was more favorable for Freundlich isotherm. The equilibrium absorption capacity was 210 mg g(-1) at initial TCP concentration of 20 mg L-1 and increased to 587 mg g(-1) when the initial TCP concentration was up to 100 mg L-1, which was much higher than those of other carbon-based adsorbents reported in literature. To the best of our knowledge, this is the first report on the synthesis of flowerlike MMC material by using LDH as template and its application as adsorbent to remove TCP. (C) 2014 Elsevier Inc. All rights reserved.

The effect of ion-doping on TiO2 nanotubes were investigated to obtain the optimal TiO2 nanotubes for the effective decomposition of humic acids (HA) through O3/UV/ion-doped TiO2 process. The experimental results show that changing the calcination temperature, which changed the weight fractions of the anatase phase, the average crystallite sizes, the Brunauer-Emmett-Teller surface area, and the energy band gap of the catalyst, affected the photocatalytic activity of the catalyst. The ionic radius, valence state, and configuration of the dopant also affected the photocatalytic activity. The photocatalytic activities of the catalysts on HA removal increased when Ag+, Al3+, Cu2+, Fe3+, V5+, and Zn2+ were doped into the TiO2 nanotubes, whereas such activities decreased as a result of Mn2+- and Ni2+-doping. In the presence of 1.0 at.% Fe3+- doped TiO2 nanotubes calcined at 550°C, the removal efficiency of HA was 80% with a pseudo-first-order rate constant of 0.158 min–1. Fe3+ in TiO2 could increase the generation of •OH, which could remove HA. However, Fe3+ in water cannot function as a shallow trapping site for electrons or holes.

The present study evaluated the efficacy of switching from premixed insulin or an insulin analogue to insulin glargine plus oral antidiabetic drugs (OADs) in patients with type 2 diabetes mellitus (T2DM). The feasibility and suitability of the regimen to the patients was examined based on islet function. Patients with T2DM (n=30) treated with stable doses of premixed insulin or an insulin analogue for eight weeks were divided into two groups according to islet function. Group A had a 2 h of C peptide (2hCP)/fasting C peptide (FCP) ratio ≤3, whereas group B had a 2hCP/FCP ratio >3. Eight weeks following the switch to insulin glargine plus OADs, a significant decrease in fasting blood glucose (FBG), 2 h postprandial blood glucose (2hPBG) and glycosylated‑haemoglobin (HbA1c) were observed in the two groups, with effective rates of 75, 42.9 and 39.3%, respectively. A distinct reduction in the insulin dose was particularly evident in group B. There was a marked decrease in FBG in group A, more so than that observed in group B. By contrast, the decrease in HbA1c was more evident in group B following the switch. A larger number of patients in group B had HbA1c≤7.0%, compared with group A. No difference in the incidence of hypoglycaemia and change of body weight were observed. Following the switch to insulin glargine plus OADs, patients with T2DM demonstrated improved blood glucose control and reduced insulin dosage. The results revealed that this switch in regimen is more suitable for patients with T2DM with 2hCP/FCP>3 and that administration of insulin glargine plus OADs is more efficacious for patients with T2DM with increased FBG levels.

Toluene is an extensively used reagent that could cause water pollution and endanger human health. In this work, an O 3 /UV/ion-doped TiO 2 nanotubes process was investigated to obtain the optimum TiO 2 nanotubes for effective toluene decomposition. Photocatalytic activity is found to be influenced by the doped-ion type by affecting the ionic radius, valence state, and configuration of the dopant. The calcination temperature and doping concentration, which change the weight fractions of the anatase phase ( f A ), the Brunauer–Emmett–Teller surface area ( S BET ), and the energy band gap ( E g ) of the catalyst, also affect the photocatalytic activity. When TiO 2 is doped with ions, S BET decreases and E g becomes narrower. The photocatalytic activities of TiO 2 for toluene removal increase after doping with Ag + , Al 3+ , Cu 2+ , Fe 3+ , Mn 2+ , Ni 2+ , V 5+ , and Zn 2+ . Moreover, the 1.0% Fe 3+ -doped TiO 2 nanotubes calcined at 550 °C have the highest catalytic activity, with a toluene removal efficiency of 70.7%.

In aquatic environments, organisms are exposed to mixtures of pollutants which may change the toxicity profile of each contaminant, compared to its toxicity alone. Carbamazepine (CBZ) and cadmium (Cd) are among the pollutants that co-occur in aquatic environments. To date, most research about their toxicity towards aquatic vertebrates is based on single exposure experiments. The present study aims to evaluate single and combined effects of CBZ and Cd on biomarkers in female Danio rerio (zebrafish) by exposing them to environmentally relevant concentrations of these two pollutants for ten days. Four kinds of biomarkers involved in antioxidant systems, energy metabolism, nervous system, and endocrine disruption, respectively, were studied. Our research results coincided with those of former studies in single exposure experiments. However, the combined exposure of CBZ and Cd exerted different responses from other studies in which these two contaminants were examined alone in zebrafish. The present study evidenced the need to conduct more coexposure studies to enhance the environmental relevance of these experimental results.

One of the most common taste and odour compounds (TOCs) in drinking water is 2-methylisoborneol (2-MIB) which cannot be readily removed by conventional water treatments. Four bacterial strains for degrading 2-MIB were isolated from the surface of a biological activated carbon filter, and were characterized as Micrococcus spp., Flavobacterium spp., Brevibacterium spp. and Pseudomonas spp. based on 16S rRNA analysis. The removal efficiencies of 2-MIB with initial concentrations of 515 ng·L−1 were 98.4%, 96.3%, 95.0%, and 92.8% for Micrococcus spp., Flavobacterium spp., Brevibacterium spp. and Pseudomonas spp., respectively. These removal efficiencies were slightly higher than those with initial concentration at 4.2 mg·L−1 (86.1%, 84.4%, 86.7% and 86.0%, respectively). The kinetic model showed that biodegradation of 2-MIB at an initial dose of 4.2 mg·L−1 was a pseudo-first-order reaction, with rate constants of 0.287, 0.277, 0.281, and 0.294 d−1, respectively. These degraders decomposed 2-MIB to form 2-methylenebornane and 2-methyl-2-bornane as the products.

Three strains of Gram-negative bacteria capable of removing geosmin from drinking water were isolated from biologically active carbon and identified to be Chryseobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp. based on physio-biochemistry analysis and 16S rRNA gene sequence analysis. Removal efficiencies of 2 mg/L geosmin in mineral salts medium were 84.0%, 80.2% and 74.4% for Chryseobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp., respectively, while removal efficiencies of 560 ng/L geosmin in filter influent were 84.8%, 82.3% and 82.5%, respectively. The biodegradation of geosmin was determined to be a pseudo first-order reaction, with rate constants at 2 mg/L and 560 ng/L being 0.097 and 0.086 day−1, 0.089 and 0.084 day−1, 0.074 and 0.098 day−1 for the above mentioned degraders, respectively. The biomass of culture in the presence of geosmin was much higher than that in the absence of geosmin.

Biological contact oxidation process of low dissolved oxygen was applied to the treatment of ABR tail water, which were pretreatment effluent for Island sewage. The reactor was built and filled with polyurethane suspension filler as carrier for biofilm growth in laboratory. The dissolved oxygen in the reactor is kept at 1.3-1.8mg/L to distinguish between traditional method which is 2.5-3.5mg/L. Influence of hydraulic retention time(HRT) on ABR tail water treatment by the process was studied. Results show that the system has good effect on removal of COD and TN under this condition. When HRT is among 4h to 12h, the removal rate of COD can be maintained at 80-90%.From period 1 to period 3, the removal rate of NH4 +N and TN at the end of each period can be recovered to a higher level, and the average removal rate after stabilization is 99% and 67% respectively which can come up to first grade of the national standard GB18918-2002. It is remarkable that when HRT is 4h, the removal rate of NH4 +-N and TN showed a significant decrease trend, the concentration of effluent was 14.79mg/L and 19.5mg/L, respectively.

An up-flow anaerobic sludge blanket reactor–microbial fuel cell–biological aerated filter (UASB–MFC–BAF) system was developed for simultaneous bioelectricity generation and molasses wastewater treatment in this study. The maximum power density of 1410.2 mW/m 2 was obtained with a current density of 4947.9 mA/m 2 when the high strength molasses wastewater with chemical oxygen demand (COD) of 127,500 mg/l was employed as the influent. The total COD, sulfate and color removal efficiencies of the proposed system were achieved of 53.2%, 52.7% and 41.1%, respectively. Each unit of this system had respective function and performed well when integrated together. The UASB reactor unit was mainly responsible for COD removal and sulfate reduction, while the MFC unit was used for the oxidation of generated sulfide with electricity generation. The BAF unit dominated color removal and phenol derivatives degradation. This study is a beneficial attempt to combine MFC technology with conventional anaerobic–aerobic processes for actual wastewater treatment.

BACKGROUND: Sulfide-containing wastewater (also containing organics) and vanadium(V)-containing wastewater exist widely and can be treated in microbial fuel cells (MFCs) based on their chemical conditions. A novel process has been investigated using MFC technologies by employing sulfide, organics and V(V) as electron donors and acceptor, respectively. RESULTS: Electrons produced by oxidation of sulfide and organics in the anode compartment were transferred to the anode surface, then flowed to the cathode through an external circuit, where they were consumed to reduce V(V). Sulfide and total organics removal approached 84.7 ± 2.8% and 20.7 ± 2.1%, with a V(V) reduction rate of 25.3 ± 1.1%. The maximum power output obtained was 572.4 ± 18.2 mW m−2. The effects of the microbes on electricity generation as well as the products of sulfide oxidation and V(V) reduction were also evaluated and analyzed. CONCLUSION: This process achieves both sulfide and V(V) removal with electricity generation simultaneously, providing an economical route for treating these kinds of wastewaters. Copyright © 2009 Society of Chemical Industry

Sulfide and vanadium (V) are pollutants commonly found in wastewaters. A novel approach has been investigated using microbial fuel cell (MFC) technologies by employing sulfide and V(V) as electron donor and acceptor, respectively. This results in oxidizing sulfide and deoxidizing V(V) simultaneously. A series of operating parameters as initial concentration, conductivity, pH, external resistance were carefully examined. The results showed that these factors greatly affected the performance of the MFCs. The average removal rates of about 82.2 and 26.1% were achieved within 72 h operation for sulfide and V(V), respectively, which were accompanied by the maximum power density of about 614.1 mW m(-2) under all tested conditions. The products generated during MFC operation could be deposited, resulting in removing sulfide and V(V) from wastewaters thoroughly.

Methyl orange (MO), a typical azo dye, is a well-known recalcitrant pollutant in dye wastewater. An aeration electrochemical system with single-chamber microbial fuel cell (MFC) as renewable power sources is proposed for MO decolorization. The enhanced color removal efficiency up to 90.4% within 360 min is observed with voltage across the aeration electrolytic reactor fixed at 700 mV. The results from gas chromatography–mass spectrometry (GC–MS) analysis indicate the destruction of MO, with generation of low molecular weight compounds such as benzene derivatives. Comparison experiments imply the indirect electrochemical oxidation of MO by generated H2O2 is mainly responsible for MO decolorization in present study. This work offers a cost-effective electrochemical method for enhancing electrochemical degradation of dyes with bioelectricity generated from MFCs.

Background Selenoprotein S (SelS) is an important endoplasmic reticulum and plasma membrane-located selenoprotein implicated in inflammatory responses and insulin resistance. However, the effects of SelS on endothelial cells (ECs) have not been reported. In the present study, the role of SelS in oxidative stress and the underlying mechanism were investigated in human ECs. Methods A SelS over-expression plasmid (pc-SelS) and a SelS-siRNA plasmid were transfected into human umbilical vein endothelial cells (American Type Culture Collection, USA). The cells were divided into four groups: control, SelS over-expression (transfected with pc-SelS), vector control, and SelS knockdown (transfected with siRNA-SelS). After treating the cells with H2O2, the effects of oxidative stress and the expression of caveolin-1 (Cav-1) and protein kinase Cα (PKCα) were investigated. Results Following treatment with H2O2, over-expression of SelS significantly increased cell viability and superoxide dismutase (SOD) activity, and decreased malondialdehyde (MDA) production and Cav-1 gene and protein expression. However, no effects on PKCα were observed. In contrast, knockdown of SelS significantly decreased cell viability, SOD activity, and PKCα gene and protein expression, and increased MDA production and Cav-1 gene and protein expression. Conclusions SelS protects ECs from oxidative stress by inhibiting the expression of Cav-1 and PKCα.

Ozone has been widely used in drinking water treatment because of its high oxidation and disinfection capability. In order to make the ozone oxidation reliable, the structure of 3 sections of the ozone contactor was employed. By changing the operation conditions of the contactor, focused was on ozone transfer effect. The results showed the best operation condition of ozone transfer was downstream in the first section and the ozone dosing ratio of 3∶3∶1 among three sections was preferred.

2-methylisoborneol (MIB) and geosmin cannot readily be removed by conventional water treatments. Biological activated carbon (BAC) process is an attractive option for MIB and geosmin removal. For BAC filter inoculated with a consortium of MIB and geosmin biodegraders, the removal efficiency of MIB (geosmin) in a period of 4d was 100% (100%), and the figure was 75% (90%) for ceramic filter. For BAC filter, removal of MIB and geosmin increased rapidly with the extension of empty bed contact time (EBCT) at first, and resulted in no obvious change when EBCT was longer than 12min. MIB (geosmin) removal efficiency of BAC filter was 99% (99%) at the stage of 12min when filter height was 550mm, among which 32–35% (18–20%) was removed by ceramic filter. The MIB and geosmin concentrations apparently decreased in the up layers of the biofilter (0–100 mm). For MIB and geosmin with an initial concentration of 500ng/L, filter height of 400mm was enough for removing MIB and geosmin to below its odor threshold concentration.

2-methylisoborneol (MIB) and geosmin cannot readily be removed by conventional water treatments. Ozonation-biological activated carbon (O 3 -BAC) process is an attractive option for MIB and geosmin removal. For MIB and geosmin with an initial concentration of 500ng/L, the removal efficiencies of MIB (geosmin) by ozonation, biodegradation and activated carbon adsorption were 51% (73%), 19% (17%) and 30% (10%), respectively when ozone dose was 2.0mg/L, empty bed contact time 12min and filter height 550mm. Filter height of 300mm was enough for removing MIB and geosmin to below its odor threshold concentration from 500ng/L. About 48% (57%), 32% (30%) and 10% (13%) of MIB (Geosmin) were removed by ozonation, biodegradation and activated carbon adsorption, respectively.