A Tape-Wrapping Strategy towards Electrochemical Fabrication of Water-Dispersible Graphene.

Graphene has achieved mass production via various preparative routes and demonstrated its uniqueness in many application fields for its intrinsically high electron mobility and thermal conductivity. However, graphene faces limitations in assembling macroscopic structures because of its hydrophobic property. Therefore, balancing high crystal quality and good aqueous dispersibility is of great importance in practical applications. Herein, we propose a tape-wrapping strategy to electrochemically fabricate water-dispersible graphene (w-Gr) with both excellent dispersibility (~4.5 mg/mL, stable over 2 months), and well-preserved crystalline structure. A large production rate (4.5 mg/min, six times faster than previous electrochemical methods), high yield (65.4% ≤5 atomic layers) and good processability are demonstrated. A mechanism investigation indicates that the rational design of anode configuration to ensure proper oxidation, deep exfoliation and unobstructed mass transfer is responsible for the high efficiency of this strategy. This simple yet efficient electrochemical method is expected to promote the scalable preparation and applications of graphene.

A chiral two-dimensional perovskite-like lead-free bismuth(III) iodide hybrid with high phase transition temperature.

Bismuth(III) iodide perovskites have attracted great attention as lead-free hybrid semiconductors, but they mainly show zero- and one-dimensional structures. Herein, we report the first two-dimensional chiral perovskite-like bismuth(III) iodide hybrid [(S)-3-aminopyrrolidinium I]2Bi2/3I4 (1) with a high phase transition temperature of 408.8 K, higher than most of the reported chiral lead-free hybrid semiconductors.

Cold Plasma Controls Nitrite Hazards by Modulating Microbial Communities in Pickled Radish.

The hazard of nitrite caused by microorganisms is the main food safety problem in the pickle production. To seek a method to control the nitrite hazards of pickles by regulating microbial community without additional substances, we focused on cold plasma because Gram-negative and Gram-positive bacteria have different degrees of sensitivity to the sterilization of cold plasma. Using radish pickles as the experimental object, based on colony counting, dynamic monitoring of pH and nitrite, qPCR and high-throughput sequencing, it was found that when the raw material was treated with dielectric barrier discharge (DBD) cold plasma at 40 kV for 60 s, Gram-negative bacteria with the potential to produce nitrite were preferentially sterilized. Meanwhile, Gram-positive bacteria dominated by the lactic acid bacteria were retained to accelerate the acid production rate, initiate the self-degradation of nitrite in advance and significantly reduce the peak value and accumulation of nitrite during the fermentation process of pickled radish. This study preliminarily verified that DBD cold plasma can inhibit the nitrite generation and accelerate the self-degradation of nitrite by regulating the structure and abundance of microbial community in radish pickles, which provides an important reference for the control of nitrite hazards in the fermentation process of pickles without additives.

A photoluminescent chiral lead-free hybrid ferroelastic semiconductor with switchable second-harmonic generation.

Chiral organic-inorganic hybrid semiconductors (COIHSs) dominated by lead halides have recently gained tremendous interest. Here, we report a lead-free photoluminescent COIHS [R-3-hydroxylpiperidinium]2SbCl5 with a bandgap of 3.14 eV. It shows a ferroelastic phase transition at 341 K accompanied by a switchable second-harmonic generation response and presents clear ferroelastic domains, which are rarely found in lead-free COIHSs.

Genomic and Metabolic Features of an Unexpectedly Predominant, Thermophilic, Assistant Starter Microorganism, Thermus thermophilus, in Chinese Inner Mongolian Cheese.

Inner Mongolian cheese is a traditional dairy product in China. It is produced without rennet, using naturally acidified milk that is simmered to achieve whey separation. In order to analyse the impact of simmering on the microbial community structure, high-throughput sequencing was performed to obtain bacterial 16S rRNA sequences from cheeses from the Ordos (ES), Ulanqab (WS), Horqin (KS) and Xilingol (XS) grasslands of Inner Mongolia. The relative abundance of an unexpected microorganism, Thermus thermophilus, ranged from 2% to 9%, which meant that its dominance was second only to that of lactic acid bacteria (LABs). Genome sequencing and fermentation validation were performed in T. thermophilus N-1 isolated from the Ordos, and it was determined that T. thermophilus N-1 could ingest and metabolise lactose in milk to produce lactate during the simmering process. T. thermophilus N-1 could also produce acetate, propionate, citrate and other organic acids through a unique acetate production pathway and a complete propionate production pathway and TCA cycle, which may affect texture and flavour development in Inner Mongolian cheese. Simultaneously, the large amount of citrate produced by T. thermophilus N-1 provides a necessary carbon source for continuous fermentation by LABs after the simmering step. Therefore, T. thermophilus N-1 contributes to cheese fermentation as a predominant, thermophilic, assistant starter microorganism unique to Chinese Inner Mongolian cheese.

Microbial Regulation of Deterioration and Preservation of Salted Kelp under Different Temperature and Salinity Conditions.

High salinity is an effective measure to preserve kelp, but salted kelp can still deteriorate after long-term preservation. In order to clarify the key conditions and microbial behavior of salted kelp preservation, 10% (S10), 20% (S20), and 30% (S30) salt concentrations were evaluated at 25 °C (T25) and 4 °C (T4). After 30 days storage, these salted kelps showed different states including rot (T25S10), softening (T25S20), and undamaged (other samples). By detecting polysaccharide lyase activity and performing high-throughput sequencing of the prokaryotic 16S rRNA sequence and metagenome, we found that deteriorated kelps (T25S10 and T25S20) had significantly higher alginate lyase activity and bacterial relative abundance than other undamaged samples. Dyella, Saccharophagus, Halomonas, Aromatoleum, Ulvibacter, Rhodopirellula, and Microbulbifer were annotated with genes encoding endonuclease-type alginate lyases, while Bacillus and Thiobacillus were annotated as the exonuclease type. Additionally, no alginate lyase activity was detected in undamaged kelps, whose dominant microorganisms were halophilic archaea without alginate lyase-encoding genes. These results indicated that room-temperature storage may promote salted kelp deterioration due to the secretion of bacterial alginate lyase, while ultra-high-salinity and low-temperature storage can inhibit bacterial alginate lyase and promote the growth of halophilic archaea without alginate lyase, thus achieving the preservation of salted kelp.

Pelagibacterium limicola sp. nov., isolated from a soda alkali-saline soil.

A Gram-staining negative, motile, non-spore-forming, rod-shaped bacterium, designated NAJP-14T, was isolated from the alkali-saline soil in Heilongjiang, Northeast China. Phylogenetic analysis based on 16S rRNA gene sequencing illustrated that strain NAJP-14T was a member of the genus Pelagibacterium, and shared 94.6-96.6% sequence identities to species from the genus Pelagibacterium. Strain NAJP-14T grew at 20-45 °C (optimum, 30 °C), pH 7.0-10.0 (optimum, pH 8.0) and in the presence of up to 5% w/v NaCl. The menaquinone was determined to be Q (10). The major fatty acids were identified as C18:1w6c (38.7%), C16:0 (16.2%) and C19:0 cyclo w8c (13.9%). The G + C content of the genomic DNA was 61.2%. Out of the 3442 predicted genes, 3391 were protein-coding genes and 51 were ncRNA. Digital DNA-DNA hybridization (dDDH) estimation and average nucleotide identity (ANI) of the strain NAJP-14T and the type strains of related species in the same family ranged between 17.9 and 21.8% and between 61.4 and 78.7%, respectively. Based on these data, it is concluded that strain NAJP-14T possesses sufficient characteristics to differentiate it from all recognized Pelagibacterium species, and should be considered as a novel species for which the name Pelagibacterium limicola sp. nov. is proposed. The type strain is NAJP-14T (= CGMCC 1.16631T, = JCM 33746T).

Optical partial discharge diagnostic in SF6 gas insulated system via multi-spectral detection.

Light emitted from partial discharges (PDs) in SF6 gas is investigated in the view point of insulation status diagnostics. Light intensity and integral spectrum of PD are proved to have significant correlations with PD activities and the involved dielectric interfaces. Based on synchronous light pulse detections in ultraviolet (UV), visible (VIS) and near-infrared (NIR) regions, the multispectral stochastic PD diagnosis is realized with more information beyond the conventional PD detections. The optical PD detection is also compared with ultra-high frequency (UHF) PD detection and acoustic emission (AE) PD detection in term of linearity, sensitivity and statistical property. Beyond that, a clustering analysis is performed on the multispectral photon counts of different conditions by quantifying them in a ternary diagram where some distinguishable regions emerge for PD recognition.

Advanced Modified Polyacrylonitrile Membrane with Enhanced Adsorption Property for Heavy Metal Ions.

Advanced modified polyacrylonitrile (PAN) membrane with high adsorption property for heavy metal ions was designed and fabricated for the first time. The introduced diazoresin-ethylenediaminetetraacetic acid (DR-EDTA) layer could effectively absorb the metal ion, such as Cu2+, Pb2+, Hg2+ in the waste water. The effects of layers, metal ion concentration, pH, temperature and cycle time were investigated. The results showed that the adsorption isotherms for Cu2+ were well fitted by Langmuir model. The maximum adsorption capacity of the modified membrane for Cu2+ was approximately 47.6 mg/g. In addition, the prepared PAN-(DR-EDTA)3 membrane could be regenerated more than 720 h based on their adsorption/desorption cycles. The results demonstrated that the modified PAN membrane could be used as effective adsorbents for heavy metal removal from waste water.

Preparation of Humidity-Sensitive Poly(Ethylene Glycol) Inverse Opal Micropatterns Using Colloidal Lithography.

Humidity-sensitive poly(ethylene glycol) (PEG) inverse opals with micropatterns of 2 µm wide anti-swell-broken grooves were prepared using polystyrene (PS) colloidal crystals as templates and colloidal lithography. Monodisperse PS colloids were deposited in an ordered manner onto glass slides using a double-substrate vertical deposition method to form colloidal crystal templates. Poly(ethylene glycol) diacrylate (PEGDA) with photoinitiator was infiltrated into the interspaces of the colloidal crystals and photo-crosslinked by UV irradiation through a photomask. After removal the PS templates and unexposed PEGDA by tetrahydrofuran (THF), PEG hydrogel micropatterns with three-dimensional ordered porous structures were obtained. The band gaps of the PS colloidal crystals and corresponding PEG hydrogel inverse opals were measured by UV-VIS reflection spectrometer, calculated by Bragg law and simulated by Band SOLVE. The obtained PEG hydrogel inverse opal micropatterns can be used as sensors for humidity sensing due to absorption and desorption of moisture in the band gap structures. The sensor had a very reliable performance after repeated humidity sensing, and could be mass produced facilely with very low cost. The photopatterned anti-swell-broken grooves play an important role in the reliability of the sensors.

A density functional theory study on the thermodynamic and dynamic properties of anthraquinone analogue cathode materials for rechargeable lithium ion batteries.

Organic redox compounds have become the emerging electrode materials for rechargeable lithium ion batteries. The high electrochemical performance provides organic electrode materials with great opportunities to be applied in electric energy storage devices. Among the different types of organic materials, conjugated carbonyl compounds are the most promising type at present, because only they can simultaneously achieve, high energy density, high cycling stability, and high power density. In this research, a series of heteroatom substituted anthraquinone (AQ) derivatives were designed theoretically so that the high theoretical capacity of AQ remained. The discharge and charge mechanism as well as the thermodynamic and dynamic properties of AQ and its derivatives were investigated using first-principles density functional theory. Using heteroatom substitution, both the thermodynamic and dynamic properties of AQ as cathode materials could be largely improved. Among these conjugated carboxyl compounds, BDOZD and BDIOZD with a simultaneously high theoretical capacity and high working potential exhibit the largest energy density of about 780 W h kg-1, which is 41% larger than that of AQ. The PQD with the smallest value of λ gives the largest charge transfer rate constant, which is about four times as large as the prototype molecule, AQ. The most interesting finding is that the lithium ion transfer plays a very important role in influencing both the discharge potential and electrochemical charge transfer rate. The present study illustrates that theoretical calculations provide a highly effective way to discover potential materials for use with rechargeable lithium ion batteries.

A novel diazoresin/poly(N-vinyl aminobutyric acid) covalent capillary coating for the analysis of proteins by capillary electrophoresis.

A novel method for the preparation of covalently linked capillary coatings of poly(N-vinyl aminobutyric acid) (PVAA) obtained from hydrolyzed polyvinylpyrrolidone was demonstrated using photosensitive diazoresin (DR) as a coupling agent. A layer-by-layer self-assembled film of DR and PVAA based on ionic bonding was first fabricated on the inner wall of capillary, then ionic bonding was converted into covalent bonding after treatment with UV light through a unique photochemical reaction of DR. The covalently bonded coatings suppressed protein adsorption on the inner surface of the capillary, and thus a baseline separation of lysozyme, cytochrome c, BSA, amyloglucosidase, and myoglobin was achieved using CE. Compared with bare capillary or noncovalently bonded DR/PVAA coatings, the covalently linked DR/PVAA capillary coatings not only improved the CE separation performance for proteins, but also exhibited good stability and repeatability. Due to the replacement of the highly toxic and moisture-sensitive silane coupling agent by DR in the covalent coating preparation, this method may provide a green and easy way to make covalently coated capillaries for CE.

Induction of antimicrobial peptides from Rana dybowskii under Rana grylio virus stress, and bioactivity analysis.

The skin glands of Ranidae are a rich source of antimicrobial peptides. In this study, the genomic RNA of Rana dybowskii was extracted from its skin while under Rana grylio virus stress. Five new cDNA sequences encoding 5 mature peptides, Ranatuerin-2YJ (GLMDIFKVAVNKLLAAGMNKPRCKAAHC), Dybowskin-YJb (IIPLPLGYFAKKP), Dybowskin-YJa (IIPLPLGYFAKKKKKKDPVPLDQ), Temperin-YJa (VLPLLETCSMTCWENNQTFGK), and Temperin-YJb (VLPLVGNLLNDLLGK), were obtained by reverse transcription polymerase chain reaction with a pair of degenerate primers designed according to the conserved terminal sequences of cDNA encoding antimicrobial peptide precursors of genus Rana. The antimicrobial activities of the peptides were analyzed, and the results demonstrated that all these peptides showed a significant anti-Rana grylio virus activity, and the virus was gradually cleared with the increase in gene expression. Among the 5 peptides obtained in this work, Ranatuerin-2YJ also showed a broad-spectrum anti-Gram-positive bacteria and anti-Gram-negative bacteria activity with a minimal inhibitory concentration of 22.5 µg/mL and 7.64% hemolysis activity, both of which were significantly lower (p < 0.05) than that of the other peptides. Moreover, Ranatuerin-2YJ was widely distributed in the skin, liver, spleen, and blood of R. dybowskii, while the other 4 peptides could only be cloned from the skin, indicating that the Ranatuerin-2YJ in vivo plays an important role in the protection against pathogen invasion.

Alpha-methylacyl coenzyme A racemase overexpression in gallbladder carcinoma confers an independent prognostic indicator.

AIMS: Increased ß-oxidation of branched-chain fatty acids provides an additional metabolic advantage for cancer cells thereby enhancing tumour development and progression. Alpha-methylacyl coenzyme A racemase (AMACR) is an enzyme essential for the catabolism of branched-chain fatty acids that allows their subsequent ß-oxidation and thus plays an important role in generating biological energy. However, the expression of AMACR has never been systemically investigated in gallbladder carcinoma. This study evaluated the expression status, associations with clinicopathological variables and prognostic implications of AMACR in a well-defined cohort of gallbladder carcinoma and confirmed their expression status in gallbladder carcinoma cells. METHODS: AMACR immunostaining was assessable in 89 cases on tissue microarrays of gallbladder carcinoma, and it was correlated with clinicopathological factors and patient survival. In three gallbladder carcinoma cell lines and one non-tumorigenic cholangiocyte, AMACR mRNA expression was measured by real-time reverse transcription PCR and the endogenous expression of AMACR protein was analysed by western blotting. RESULTS: AMACR overexpression was significantly associated with an advanced primary tumour status (p=0.027) and American Joint Committee on Cancer stage (p=0.027), an increased histological grade (p=0.002) and vascular invasion (p=0.017). Importantly, AMACR overexpression independently predicted worse disease-specific survival (p=0.0452, RR 1.887). Expression levels of AMACR mRNA and total protein in various cells were comparable. The abundance of AMACR expression increased in tumour cells and was even higher in the metastatic cell line. CONCLUSIONS: In primary gallbladder carcinoma, AMACR overexpression was correlated with important prognosticators and independently portended worse outcomes, highlighting the potential prognostic and therapeutic utility of AMACR in gallbladder carcinoma.

[Research and analysis of data source--analysis of the items of medical plants in Xiandai Bencao Gangmu].

Scientific data is the source of innovation in knowledge. In order to change the situation that there is few information in plenty of data and to obtain useful knowledge which has high information content, it is necessary to clean data and ensure data's accuracy and without noise off when database is established initially. High-quality data comes from high-quality data source. But incomplete and incorrect and irregular data exist widely in the data source of Chinese materia medica. The phenomenon of synonyms and homonym is quite serious, and there is no unified description for the name and origin of Chinese materia medica among different data sources. So data processing including data analysis and research is very important in the establishment of Chinese materia medica database. In order to get the most accurate and standard data, this paper analyzed the items of Medical Plants in Xiandai Bencao Gangmu, including classification analysis of medical plants: distribution analysis of different classes and analysis of medical part; analysis of synonyms and homonym; analysis of incorrect data and analysis of advantage and disadvantage of data sources.

Optimization of sterilization of Escherichia coli in milk by surfactin and fengycin using a response surface method.

In this paper, the sensitivity of Escherichia coli to surfactin and fengycin was observed, and the optimization of the antimicrobial activity of surfactin and fengycin to E. coli in milk by a response surface methodology was studied. Results showed that E. coli had high sensitivity to these antibiotics, whose minimal inhibitory concentrations were 15.625 microg.mL(-1) and 31.25 microg.mL(-1), respectively. The optimization result indicated that E. coli could be sterilized by 5 orders of magnitude when the temperature was 5.5 degrees C, the action time was 15.8 h, and the concentration (surfactin/fengycin weight ratio 1:1) was 14.63 microg.mL(-1).

[Discussion on optimizing data processing of Chinese materia medica].

Correct data without noise is the basis for obtaining useful information and knowledge. The database system of Chinese materia medica is the application of database technology in the field of Chinese materia medica. Its establishment is based on the analysis, processing and supplementary of much irregular raw data during studying Chinese materia medica information. This paper reviewed several key problems in the data processing of Chinese materia medica based on the information system of Chinese herbal medicine that we are constructing.

Optimization of inactivation of endospores of Bacillus cereus by antimicrobial lipopeptides from Bacillus subtilis fmbj strains using a response surface method.

Bacillus subtilis fmbj can produce a lipopeptide antimicrobial substance, the main components of which are surfactin and fengycin. In this paper, the sensitivity of Bacillus cereus to antimicrobial lipopeptides from B. subtilis fmbj was observed, and the effect of the microstructure of antimicrobial lipopeptide on spores of B. cereus was investigated. At the same time, the optimization of the inactivation of antimicrobial lipopeptides to spores of B. cereus by a response surface methodology was studied. Results showed that B. cereus had high sensitivity to it, whose minimal inhibitory concentration was 156.25 microg/ml. It could result in the death of spores by destroying the structure of resting spores and sprouting spores, as was observed by transmission electron microscopy. The optimization result indicated that spores of B. cereus could be inactivated by 2 orders of magnitude when the temperature was 29.6 degrees C, the action time was 7.6 h, and the concentration was 3.46 mg.ml(-1).