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In this study, a Cu–Cu2O junction structure was grown in situ on the surface of Cu plates via chemical etching at room temperature. A novel dopamine (DA) electrochemical sensor based on Cu–Cu2O/glassy carbon electrode (Cu–Cu2O/GCE) was constructed. The Cu–Cu2O/GCE sensor exhibited a wide linear range of 0.03–2.45 mM and a low limit of detection of 7.1 nM (S/N = 3) for DA. The enhanced performance was due to the unique void structure, which increased catalytic active sites and electrochemical active surface areas. Moreover, the optimization of the Cu2O–to–Cu ratio allowed for the effective regulation of the electron configuration of the Cu–Cu2O junction structure. The Cu–Cu2O/GCE sensor also exhibited good reproducibility, stability, and anti-interference ability. [ABSTRACT FROM AUTHOR]

The article offers information on a study which investigates the localization of Bordetella avium in chickens with bacterial infection through indirect immunoperoxidase technique.

The adsorption of PFOS by activated sludge and EPS-removed sludge was conducted to investigate the adsorption mechanism of activated sludge and the effect of EPS on this adsorption process. The experimental results indicated that the adsorption process of PFOS onto activated sludge and EPS-removed sludge fitted the pseudo-second-order model, with equilibrium absorption capacities ( q e ) of 0.46 mg·g -1 and 0.38 mg·g -1 , respectively. The sorption isotherm accorded well with the Freundlich, Langmuir, and Temkin models. Chemisorption played an important role in the adsorption of PFOS on the activated sludge. Ca 2+ and Cu 2+ contributed to PFOS adsorption on the activated sludge through an ion-bridging effect. Adsorption efficiency was better on the normal activated sludge compared to the EPS-removed sludge. FTIR and XPS were used to analyze the variations of functional groups before and after sorption. The results showed that the amount of functional groups such as hydroxyl, carboxyl, and amidogen on EPS-removed sludge was lower; however, these functional groups were found to have participated in the PFOS adsorption process. It is concluded that carboxyl and amidogen contained in protein of EPS provided reaction sites for PFOS adsorption, thus EPS components played a vital role in PFOS adsorption on the activated sludge.

In this study, municipal sludge, sawdust, and mushroom residues were used as raw materials for composting, and thermophiles and white-rot fungi were added into the compost in stages. By measuring physicochemical factors, including temperature, pH value, organic matter, water-soluble organic carbon, moisture content, total nitrogen, NH 4 + -N, NO 3 - -N, and germination index during the composting process, the effect of exogenous bacteria inoculation on the efficiency of compost was determined. By means of high-throughput sequencing technology, the variation of bacterial community structure and the impact of exogenous bacteria inoculation on bacterial community structure during sludge composting were also investigated. The results showed that the inoculation extended the high temperature duration, decreased the nitrogen loss, and accelerated the decomposition and detoxification of the compost. During the entire period of composting, the structure of bacterial community changed significantly. There was low similarity of bacterial community structure among different stages of the same composting, but high similarity was observed in different composting of the same period. The inoculation of thermophilic bacteria improved the abundance of bacterial community and increased the proportions of dominant genera in thermophilic phase, but changed no species of dominant genera. Canonical correspondence analysis showed that pH had the highest influence on the structure of bacterial community and that temperature possessed positive correlation with nine genera.

To investigate population structure and marker assisted breeding, fast isolation by AFLP of sequences containing repeats (FIASCO) and GenBank database mining were used to develop novel microsatellite markers for sea perch (Lateolabrax japonicus). Genomic DNA fragments containing SSR sequences were captured by hybridization to (GT)(13) biotin-labeled probe and were ligated to PMD18-T vector. Among 150 randomly chosen clones from the SSR-enriched library, 66 sequences contained microsatellite motif over five repeats. In addition, 540 cDNA sequences and 132 ESTs of Lateolabrax japonicus were downloaded from GenBank and screened for di-, tri- and tetra-nucleotide repeats, while 22 sequences were found to contain microsatellites. As a result, 15 microsatellite loci were shown to be polymorphic in 30 Lateolabrax japonicus individuals, with the alleles ranging from two to ten, the observed heterozygosities from 0.6000-1.0000, and the expected heterozygosities from 0.5079-0.8890. Four loci (SP17, SP52, SP94 and SP468) were deviated from HWE in the sampled population after Bonferroni's correction, and no linkage disequilibrium was found among all loci (P<0.003), whereas null alleles were detected at locus SP52 (P<0.05). Among 15 polymorphic loci, the PIC values, which can be used for related population genetics analysis, were all above 0.5, with the exception of SP17 and SP468.

Glutamate dehydrogenase (GDH) is a key enzyme in the biosynthesis of glutamate. The GDHs from Corynebacterium glutamicum S9114 the most commonly used strain in glutamate fermentation, were purified and their molecular structures and properties characterized. The coenzymes were also studied in the hope to increase glutamate production. Cells were harvested at mid-exponential phase by centrifugation and washed with Tris-HCl buffer containing DTT and EDTA (pH 7.5). The cells were then disrupted using a French pressure cell press and the supernatant was collected by centrifugation. The extract was concentrated by 70-fold using the AKTA-100 FPLC system employing a DEAE-cellulose ion exchange column, a hydrophobic interaction chromatography (HIC) and Sephadex G-200 gel filtration. The purified extracts contained NADPH-dependent GDH and NADH-dependent GDH. Both of the enzymes were highly specific for the coenzymes. The molecular masses of the NADPH-dependent GDH and its subunit were 188kD and 32kD respectively, suggesting the enzyme is a homo-hexamer. Our data reported for the first time the presence of NADH- dependent GDH in Corynebacterium glutamicum S9114, similar to other microorganisms containing both GDHs. The NADPH-dependent and NADH-dependent GDH in Corynebacterium glutamicum S9114 may participate in the assimilation and dissimilation of ammonia respectively. The absorptions of NADPH-dependent GDH was very weak at 280nm but very high at 215nm, suggesting a low phenylalanine and tyrosine content in the enzyme.