Cost-effective method of benzene-containing wastewater treatment using floating electro-Fenton system.

Traditional electro-Fenton systems must continuously supply oxygen to the cathode, which leads to extensive volatilisation of benzene in solutions. In this study, we adopted a floating cathode electro-Fenton system without bubbling oxygen into the solution to treat benzene-containing wastewater. The effects of the floating cathode position and main reaction parameters on benzene degradation were analysed, and the degradation cost was estimated. The results indicated that the electro-Fenton system with floating cathode could effectively degrade benzene in solutions. For the cathode, the complete utilisation of air and oxygen released from the anode was crucial. The benzene degradation rate increased with an increase in benzene concentrations. Additionally, pH mainly affected the existing ionic state of iron and production ratio of active substances. The current intensity significantly influenced the reaction activity. Using the floating cathode electro-Fenton method, the benzene removal ratio in the solution could reach 74.80% after 60 min under the optimum reaction conditions. For the floating cathode electro-Fenton system, the cost of treating benzene-containing sewage per cubic metre was $1.2187, which is significantly lower than that for traditional electro-Fenton technology ($1.4000). Hence, the floating cathode electro-Fenton system is an economical and efficient method for benzene degradation in solutions.

Observational comparisons of intestinal microbiota characterizations, immune enzyme activities, and muscle amino acid compositions of loach in paddy fields and ponds in Sichuan Province.

A balanced intestinal microbial ecosystem is crucial for the growth and health of animals because it can influence the digestion and absorption of nutrients in the intestine. Different culture conditions may change the ecology of microbial in intestine and thus affect the overall growth performance of an animal. In this study, we compared intestinal morphologies, microbiota characterizations, immune enzyme activities, and muscle amino acid compositions of loach cultured in paddy fields and ponds. The fish were fed with the same diets from May 5 to November 5 (2015) in three paddy or ponds. Fish samples were collected for analysis in the August (summer season) and November (fall season) during the feeding trial. In both culture conditions, results based on microscopy observation showed that the intestinal perimeter, fold height, fold radical, and total absorption of the gut were significantly higher in the foregut than that found in the midgut and hindgut (P < 0.01). The average final body weight of fish was similar between the two culture conditions (P > 0.05). The percentage of carcass weight to whole loach weight for samples collected from paddy field (91.6 ± 1.1) was significantly higher than the index measured for loach from pond (87.3 ± 3.4, P < 0.05). Results based on denaturing gradient gel electrophoresis demonstrated that the Shannon-diversity index, evenness, and richness of intestinal flora were increased from summer to fall in paddy cultivation. In pond culture condition, however, the above indexes obtained from mucosa and intestinal contents decreased in fish from summer to fall. The sequencing results of bands indicated that the predominant microorganisms are Proteobacteria, Firmicutes, and Actinobacteria in the intestine of fish being cultured in both cultures. Activities of alkaline phosphatase (AKP, in two culture conditions) and superoxide dismutase (SOD, in paddy field) presented a gradual decrease trend from foregut to hindgut of fish. The activities of acid phosphatase (ACP, in midgut), AKP (in midgut and hindgut), SOD (in foregut), and lysozyme (LZM, in midgut) were significantly higher in fish cultured in paddy than those in pond (P < 0.01). In addition, the percentage of some essential amino acids (valine, methionine, and phenylalanine) based on total amino acids in muscle was significantly higher in fish cultured in paddies than in ponds. In summary, the fish cultured in paddy or pond was not significantly different in growth but the two culture conditions seems to generate different carcass yield and changed the amino acid profiles of fish muscle. The similar predominance microorganisms were identified in the intestine of fish from two conditions, and the quantification of microbial in the intestine will be determined in the future, but part activities involved in immune protection were higher for fish cultured in paddy fields.

TRAF3 gene regulates macrophage migration and activation by lung epithelial cells infected with Aspergillus fumigatus.

IMPORTANCE: Aspergillus fumigatus can infect immunocompromised individuals and cause chronic and fatal invasive fungal infections. A better understanding of the molecular mechanisms of A. fumigatus-host interactions may provide new references for disease treatment. In this study, we demonstrated that the TRAF3 gene plays an important role in the early infection of A. fumigatus by regulating the resistance of lung epithelial cells to A. fumigatus. Macrophages are the most abundant innate immune cells in the alveoli; however, few studies have reported on the interactions between lung epithelial cells and macrophages in response to A. fumigatus invasion. In our study, it was demonstrated that the TRAF3 gene reduces migration to macrophages and cytokine production by negatively regulating lung epithelial cell adhesion and internalization of A. fumigatus spores. Together, our results provide new insights into lung epithelial cell-macrophage interactions during A. fumigatus infection.

Effect of oxygen functional groups on competitive adsorption of benzene and water on carbon materials: Density functional theory study.

It is important to study the effect of oxygen-containing functional groups on the competitive adsorption mechanism of benzene and water on the surface of carbon materials, and to directional modification of activated carbon to improve its selective adsorption of benzene in air. In this study, the adsorption characteristics of benzene and water on original and linked ester, carboxyl, hydroxyl, carbon materials linked by ether groups were calculated by quantum chemical simulation based on density functional theory. The types and proportions of weak interactions in the adsorption process were calculated by energy decomposition analysis, and the adsorption mechanism of carbon materials for water and benzene was described. The influence and contribution of oxygen-containing functional groups on the adsorption of benzene and water were further analyzed by van der Waals potential and electrostatic potential, respectively, so as to determine the difference in the adsorption effect of different types of oxygen-containing functional groups on the two molecules. It was found that the carboxyl group has a great influence on the hydrophilicity of carbon materials, and the electrostatic potential distribution before and after linking the carboxyl group changed significantly. Therefore, they can attract each other with water through hydrogen bonds and occupy the surface adsorption sites of carbon materials, thereby inhibiting the adsorption of benzene on carbon materials. On the contrary, due to its hydrophobic properties, the ether group will free up adsorption space for the adsorption of benzene on the surface of the carbon material, which is beneficial to the adsorption of benzene. The adsorption experiments were carried out, and the results were consistent with the simulation. This study provides an idea for preparing efficient carbonaceous adsorbent of benzene and reducing benzene pollution in industry.

Does a Polycentric Spatial Structure Help to Reduce Industry Emissions?

City planners are increasingly drawn to ways of transforming urban spatial structure as an important strategy for reducing pollutant emissions. As its main contribution, this paper uses firm-level emissions data to quantify impact mechanisms related to factor flow, firm size, and division of labour. We examine the effects of spatial polycentricity on firm-level industrial emissions, using a pooled cross-sectional model, based on emissions data from individual firms in China. We show that, all else being equal, polycentric spatial structures help to reduce the emissions of industrial firms. This finding is not affected by index measures, changes in industrial structure, or city-sample selection. A mechanism analysis shows that polycentric structures not only enhance the emission-reduction effects of factor flow and firm size, but also reduce firm-level emissions by strengthening the urban division of labour. Our findings support the emission-reduction performance of polycentric spatial structures, promoting the integration of city planning and industrial policies that jointly contribute to reducing firm-level emissions and preventing and controlling air pollution.

Role of upregulation of the KATP channel subunit SUR1 in dopaminergic neuron degeneration in Parkinson's disease.

Accumulating evidence suggests that ATP-sensitive potassium (KATP ) channels play an important role in the selective degeneration of dopaminergic neurons in the substantia nigra (SN). Furthermore, the expression of the KATP channel subunit sulfonylurea receptor 1 (SUR1) is upregulated in the remaining nigral dopaminergic neurons in Parkinson's disease (PD). However, the mechanism underlying this selective upregulation of the SUR1 subunit and its subsequent roles in PD progression are largely unknown. In 3-, 6-, and 9-month-old A53T α-synuclein transgenic (α-SynA53T+/+ ) mice, only the SUR1 subunit and not SUR2B or Kir6.2 was upregulated, accompanied by neuronal damage. Moreover, the occurrence of burst firing in dopaminergic neurons was increased with the upregulation of the SUR1 subunit, whereas no changes in the firing rate were observed except in 9-month-old α-SynA53T+/+ mice. After interference with SUR1 expression by injection of lentivirus into the SN, the progression of dopaminergic neuron degeneration was delayed. Further studies showed that elevated expression of the transcription factors FOXA1 and FOXA2 could cause the upregulation of the SUR1 subunit in α-SynA53T+/+ mice. Our findings revealed the regulatory mechanism of the SUR1 subunit and the role of KATP channels in the progression of dopaminergic neuron degeneration, providing a new target for PD drug therapy.

Contribution of NADPH-cytochrome P450 Reductase to Azole Resistance in Fusarium oxysporum.

Fusarium species exhibit significant intrinsic resistance to most antifungal agents and fungicides, resulting in high mortality rates among immunocompromised patients. Consequently, a thorough characterization of the antifungal resistance mechanism is required for effective treatments and for preventing fungal infections and reducing antifungal resistance. In this study, an isolate of Fusarium oxysporum (wild-type) with broadly resistant to commonly antifungal agents was used to generate 1,450 T-DNA random insertion mutants via Agrobacterium tumefaciens-mediated transformation. Antifungal susceptibility test results revealed one mutant with increased sensitivity to azoles. Compared with the resistant wild-type, the mutant exhibited low MICs to KTZ, ITC, VRC, POS, and PCZ (0.125, 1, 0.06, 0.5, and 0.125µg/ml, respectively). The T-DNA insertion site of this mutant was characterized as involving two adjacent genes, one encoding a hypothetical protein with unknown function and the other encoding the NADPH-cytochrome P450 reductase, referred as CPR1. To confirm the involvement of these genes in the altered azole susceptibility, the independent deletion mutants were generated and the Cpr1 deletion mutant displayed the same phenotypes as the T-DNA random mutant. The deletion of Cpr1 significantly decreased ergosterol levels. Additionally, the expression of the downstream Cyp51 gene was affected, which likely contributed to the observed increased susceptibility to azoles. These findings verified the association between Cpr1 and azole susceptibility in F. oxysporum. Furthermore, this gene may be targeted to improve antifungal treatments.

Chronic chlorpyrifos exposure induces oxidative stress, apoptosis and immune dysfunction in largemouth bass (Micropterus salmoides).

This study was undertaken to (a) evaluate the destructive effects of chronic exposure to low-dose of chlorpyrifos (CPF) on antioxidant system and immune function in largemouth bass (Micropterus salmoides), and (b) to examine whether dietary supplementation of curcumin can mitigate the adverse effects induced by CPF contamination. The experiment consisted of three groups (with three replicates, 30 fish per replicate) which lasted for 60 days: A control group (without CPF exposure or CU application), CP group (exposed to 0.004 mg/L of CPF), and CU group (exposed to 0.004 mg/L of CPF and fed a diet containing 100 mg curcumin per kg feed). The results showed that CPF contamination leads to reduced weight gain, severe histopathological lesions, decreased activity of antioxidant enzymes and down-regulated expression of antioxidant-related genes. Moreover, CPF upregulated the expression of pro-inflammatory genes such as TNF-α, IL-8, IL-15, downregulated anti-inflammatory genes TGF-ß1, IL-10, and promoted apoptosis through overexpression of Caspase-3, Caspase-8, caspase-9 and Bax. In addition, curcumin supplementation showed significant improvement in oxidative stress, apoptosis and immune dysfunction, but the improved effect gradually weakened during the exposure last. Gas chromatography-mass spectrometry (GC-MS) analysis for accumulation of CPF in muscle supported the changes of general physiological structure, excessive apoptotic responses, abnormal antioxidant and immune system functions and posed potential human health risks to children based on target hazard quotient. These results suggested that chronic exposure to CPF can cause oxidative stress, apoptosis and immune dysfunction, and that curcumin have the potential to reduce pesticides residues in fish. This also highlights the importance of monitoring pesticides residues in aquatic products and aquaculture aquatic environments.

Time-delay estimation based computed torque control with robust adaptive RBF neural network compensator for a rehabilitation exoskeleton.

A new approach to gait rehabilitation task of a 12 DOF lower limb exoskeleton is proposed combining time-delay estimation (TDE) based computed torque control (CTC) and robust adaptive RBF neural networks. In addition to the conventional advantages of the CTC, TDE technique is integrated to estimate unmodeled dynamics and external disturbance. To realize more accurate tracking, a robust adaptive RBF neural networks compensator is designed to approximate and compensate TDE error. The final asymptotic stability is guaranteed with Lyapunov criteria. To validate the proposed approach, co-simulation experiments are realized using SolidWorks, SimMechanics and MATLAB/Robotics Toolbox. Compared to CTC, sliding mode based CTC and TDE based CTC, the higher performances of the proposed controller are demonstrated by co-simulation.

Series of Cadmium(II) Coordination Polymers Based on a Versatile Multi-N-Donor Tecton or Mixed Carboxylate Ligands: Synthesis, Structure, and Selectively Sensing Property.

Five Cd(II) metal-organic frameworks (MOFs), [Cd(HL)2] (1), [Cd(HL)2(H2O)2] (2), [Cd3(HL)2(obda)2] (3), [Cd2(HL)2(ohmbda)(DMA)(H2O)] (4), and [Cd2(HL)(btc)(H2O)2]·3H2O (5), were prepared by reactions of Cd(NO3)2·4H2O with 1-(1H-imidazol-4-yl)-4-(4H-tetrazol-5-yl)benzene (H2L) or mixed carboxylate ancillary ligands of 1,2-benzenedicarboxylic acid (H2obda), 5-hydroxy-1,3-benzenedicarboxylic acid (H2ohmbda), and 1,3,5-benzenetricarboxylic acid (H3btc), respectively. Their structures have been characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy (IR), thermogravimetric analysis, and powder X-ray diffraction. Compounds 1 and 2 are supramolecular isomeric frameworks without consideration of the solvent molecules. Complex 1 exhibits a binodal (3, 5)-connected two-dimensional (2D) layer structure with the point (Schläfli) symbol of (52·6)(55·64·7), while complex 2 shows a 2D + 2D → 3D (three-dimensional) framework. Complex 3 is a (3, 5, 6)-connected tetranodal 3D net with the point (Schläfli) symbol of (4·82)2(45·6·84)2(45·65)2(48·66·8). Compound 4 is a (3, 3, 8)-connected trinodal 3D net with the point (Schläfli) symbol based on a binuclear [Cd2N2O] subunit, while 5 is a 2-nodal (3, 4)-connected 2D V2O5-type network based on [Cd2N2(COO)2] SBU. The studies of molecular sensing properties show that the luminescent MOFs can be employed as fluorescent sensors for the detection of Fe3+ and nitro compounds. Compound 1 and 3 exhibit quenching responses for Fe3+ in dimethylformamide solution with detection limits of 2.3 × 10-6 and 8.6 × 10-7 M, respectively. Meanwhile, compound 5 can sense 4-nitrophenol with a detection limit as low as 5.75 × 10-7 M.

The expression of KATP channel subunits in alpha-synuclein-transfected MES23.5 cells.

BACKGROUND: SUR1, one of the subunits of ATP-sensitive potassium (KATP) channels, was found to be highly expressed in mRNA levels in the substantia nigra (SN) of Parkinson's disease (PD) brains. Though the mechanism of the selective dopamine (DA) neurons death is still unknown, some studies have demonstrated that selective activation of the KATP channels in the SN might be associated with the degeneration of DA neurons. The objective of our study is to examine the expressions of KATP channel subunits in dopaminergic cells with alpha-synuclein (α-Syn) transfection. METHODS: In this study, we detected the KATP channel subunits mRNA levels in MES23.5 cells by real-time quantitative PCR after the cells transfected with α-Syn. RESULTS: Our results showed that the mRNA levels of SUR1 subunit were markedly increased by 35% in WT α-Syn overexpression cells and by 31% in A53T α-Syn overexpression cells, respectively. However, the mRNA levels of SUR2B and Kir6.2 subunit have no obviously differences from the controls. CONCLUSIONS: We showed that the mRNA levels of SUR1 but not SUR2B or Kir6.2 were selectively upregulated in MES23.5 cells over-expressed with α-Syn. The findings demonstrated that the SUR1 overexpressed might be involved in the process of PD.

Investigation of Behavioral Dysfunctions Induced by Monoamine Depletions in a Mouse Model of Parkinson's Disease.

Parkinson's disease (PD) is characterized not only by typical motor symptoms, but also by nonmotor symptoms in the early stages. In addition to the loss of dopaminergic (DAergic) neurons, progressive degenerations of noradrenergic (NA) and serotonergic (5-HT) neurons were also observed. However, the respective effects and interactions of these monoamine depletions on certain nonmotor symptoms are still largely unknown. In the present study, we performed selective depletions of NA, 5-HT and DA in mice by intraperitioneal injection of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSP-4), 4-chloro-L-phenylalanine (pCPA) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), respectively. DSP-4 led to a 34% decrease in the number of NAergic neurons in the locus coeruleus, and MPTP led to a 30% decrease in the number of DAergic neurons in the substantia nigra. Although there was no obvious change in the number of 5-HTergic neurons in the dorsal raphe nucleus after pCPA treatment, the levels of 5-HT and its metabolite in the frontal cortex and hippocampus were reduced, respectively. Locomotor activity deficit was induced by DA depletion and a decrease in traveled distance was potentiated by additional NA depletion. Despair-associated depressive-like behavior could be observed in every group. Anxiety states emerged only from the combined depletion of two or three monoamines. However, combined depletion of the three monoamines dramatically induced anhedonia, and it could also aggravate the depressive-like and anxiety behavior. Furthermore, NA depletion significantly reduced spatial learning and memory ability, which was not enhanced by additional 5-HT or DA depletion. Our data highlighted the interactive role of NA, 5-HT and DA in the motor, emotional and cognitive deficits, providing new insight into the complex orchestration of impaired monoaminergic systems that related to the pathology of PD.

Fabrication of a multifunctional carbon nanotube "cotton" yarn by the direct chemical vapor deposition spinning process.

A continuous cotton-like carbon nanotube fiber yarn, consisting of multiple threads of high purity double walled carbon nanotubes, was fabricated in a horizontal CVD gas flow reactor with water vapor densification by the direct chemical vapor deposition spinning process. The water vapor interaction leads to homogeneous shrinking of the CNT sock-like assembly in the gas flow. This allows well controlled continuous winding of the dense thread inside the reactor. The CNT yarn is quite thick (1-3 mm), has a highly porous structure (99%) while being mechanically strong and electrically conductive. The water vapor interaction leads to homogeneous oxidation of the CNTs, offering the yarn oxygen-functionalized surfaces. The unique structure and surface of the CNT yarn provide it multiple processing advantages and properties. It can be mechanically engineered into a dense yarn, infiltrated with polymers to form a composite and mixed with other yarns to form a blend, as demonstrated in this research. Therefore, this CNT yarn can be used as a "basic yarn" for various CNT based structural and functional applications.