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Purified liquid is obtained in the last stage of the zinc-smelting purification process, and real-time detection of its trace metal ion concentration is beneficial in providing effective information for the purification of zinc hydrometallurgy. We added Cu(Ⅱ), Co(Ⅱ) and Fe(Ⅲ) standard solutions to the purified liquid obtained from zinc smelting based on the analysis system of Nitroso R salt to simulate the fluctuation of the actual ion concentration, and adopted UV-vis spectrometry to determine the concentration of metal ions. Then, we adopted the strategy of "separation-extraction-calibration" strategy to quantitatively analyze the concentration of trace metal ions, namely, Cu, Co, and Fe, simultaneously. Elite Variable Cluster and Improved Local Weighted Partial Least Squares (EVC-ILWPLS) algorithm are proposed for feature extraction and multivariate calibration model. In the approach, the most effective information variable clustering is filtered using forward elimination and backward clustering, and then ILWPLS based on variable weighted and sample weighted is used to determine trace metal ions concentration. Experimental results indicate that EVC-ILWPLS can not only select effective variables quickly and accurately, but also establish a reliable regression model for spectral data with complex multivariate relationships and strong collinearity. A comparison between the proposed and other conventional methods shows that this proposed strategy can determine the concentration of Cu, Co, and Fe with the lowest RMSE and MRE. Therefore, the developed method can be implemented as a promising method for quantitatively analyzing trace metal ions concentration, and it provides a guiding significance in the analysis and processing of multivariate collinearity spectrum data.

Paralytic shellfish toxins (PSTs) produced by certain marine dinoflagellates accumulate in filter-feeding marine bivalves. We used LC-MS/MS to detect and quantify 13 PSTs in 188 shellfish samples of 14 species collected from Shenzhen city’s Buji seafood wholesale market from March 2019 to February 2020. Twenty-six of 188 shellfish samples (13.8%) were PSTs detectable. Within 14 species, 10 out of 34 noble clam Chlamys nobilis samples contain detectable PSTs with the highest detection rate 29.4%. Seven out of 17 samples from Nan’ao island contained detectable PSTs with the highest detection rate 41.2% among 11 origins. Samples containing PSTs were concentrated in spring and winter, with the highest levels in March>December>January. Among PSTs detected, C1 was dominant. Acute dietary exposure assessment for Shenzhen residents were based on mean adult body weight, 99th percentile daily shellfish consumption of Shenzhen food consumption survey 2008 and maximum PSTs concentration for each shellfish species. The outcome for Chlamys nobilis was 2.4~3.7-fold higher than recommended ARfDs. Mean PSTs concentration, P99, and mean shellfish consumption were used to assess chronic dietary exposure. The results were lower than recommended ARfDs. In conclusion, residents in Shenzhen are at risk for acute PSTs poisoning, while relatively safe from chronic PSTs exposure.

Milk fan is a cheese-like fermented milk product produced in Yunnan Province, China. In this study, we characterized the microbial communities of milk fan from 6 distinct geographical origins and investigated their generation of volatile organic compounds (VOC). The microbial communities found in all milk fan samples were dominated by Lactococcus, Lactobacillus, and Raoultella bacteria and Rhodotorula, Torulaspora, and Candida fungi. Samples from the Kunming and Weishan regions had greater bacterial richness, and samples from Xizhou had greater fungal community richness. Sixty prominent VOC (i.e., those having odor activity values ≥1), including esters, acids, alcohols, aldehydes, ketones, and aromatic compounds, were identified by gas chromatography-mass spectrometry analysis of milk fan samples. Pearson correlation analysis revealed that Lactobacillus, Rhodotorula, Lodderomyces, and Debaryomyces had significant correlations with various VOC, revealing a total of 13 compounds that are characteristic of the odor of milk fan. These bacteria and fungi are therefore identified as functional microorganisms that collectively create the complex VOC profile of milk fan. This study provides a comprehensive overview of the microbial community of milk fan and demonstrates its contribution to the unique aroma profile of this fermented milk product

Producing hydrogen through photocatalytic water splitting is a feasible and efficient route for resolving the problems associated with energy and the environment, and great efforts have been devoted to improving solar-to-hydrogen (STH) efficiency. Here, we study an arsenene/g-C3N4 van der Waals heterostructure as a possible photocatalyst for water splitting. Using first principles calculations, we find that the heterostructure is an indirect-gap semiconductor with a type-II band alignment and low exciton binding energy, facilitating the effective separation of photogenerated electrons and holes. Comparing the band edge positions with the redox potentials of water demonstrates that the heterostructure is a potential photocatalyst for water splitting in a neutral environment. Meanwhile, the heterostructure shows significantly enhanced optical absorption beyond the constituent monolayers in both visible and ultraviolet regions. Its STH efficiency limit can reach up to 15.8%, which is quite promising for commercial applications. Thermodynamic analyses for redox reactions suggest facile hydrogen generation on the heterostructure. These extraordinary properties enable the arsenene/g-C3N4 heterostructure to be a promising water-splitting photocatalyst.

Constructing two-dimensional (2D) van der Waals heterostructures with novel physical properties is regarded as a promising strategy to obtain desirable optoelectronic devices. Here, by systematic first-principles calculations, we demonstrate that the 2D blue phosphorene/Sc2CX2 (X = O, F) van der Waals heterostructures are robust type-II band alignment semiconductors with an indirect band gap, and exhibit low exciton binding energies as well as having a strong light-harvesting ability in the UV-visible region. Remarkably, both are found to be potential photocatalysts for water splitting in acidic and/or neutral solutions. Interestingly, the external strain can significantly increase the power conversion efficiency (PCE) of the blue phosphorene/Sc2CF2 heterostructure up to 20.87% (increased by 36%). These results indicate that the blue phosphorene/Sc2CX2 heterostructures will have extensive application prospects in the field of solar energy utilization.

The effects of S and Se treatment on cabbage, especially the interactions of S and Se metabolism with the biosynthesis of glucosinolate (GSL), including glucoraphanin, which is a major aliphatic GSL in cruciferous vegetables and the precursor of the anticancer compound sulforaphane, were examined. Cabbage plants were treated with sulfate and selenite (SeO32−), and the total S, Se, and GSL contents of cabbage head and outer foliage leaves were measured. Results showed that selenite treatment was beneficial to GSL biosynthesis and Se accumulation in cabbage head and outer foliage leaves. GSL synthesis was induced by exogenous selenite-elevated sulfate treatment at certain concentration ratios, i.e., 50-μΜ selenite + 1-mΜ sulfate or 100-μΜ selenite + 4-mΜ sulfate. A high exogenous sulfate concentration was more favorable to GSL accumulation than a low sulfate concentration. According to the relative expression of genes on GSL synthesis, an increase in the GSL content was attributed to the upregulation of gene expression and possible transportation from the outer foliage leaf to the head of cabbage. These results might be helpful for increasing the health benefits of cabbage by supplying exogenous S and Se. Further research should explore the effects of sulfate and selenite on GSL precursor substances to reveal the reason why total GSL contents increased.

A special target structure for erbium (Er)-zirconium (Zr) co-deposition is proposed, based on the hollow cathode effect. To study the effect of rare earth on the alloyed layer, Zr-Er alloyed layers...

A series of Ce3+, Tb3+ and Yb3+ tri-doped feldspar CaAl2Si2O8 (CASO) phosphors have been successfully synthesized at ∼ 1350 °C under reducing atmosphere. Optical properties of these phosphors have been investigated as a function of doping concentrations by using fluorescence spectra and decay lifetime analysis in detail. The XRD patterns and structure refinements indicate that the dopants do not change the phase structure of host lattice. For Ce3+/Tb3+/Yb3+ all occupied at Ca2+ sites, charge compensation requires cationic vacancies ( V C a / / ) to maintain electrical neutrality instead of oxygen at interstitial site ( O i 2 − ) because the phosphors were synthesized under reducing atmosphere. The near ultraviolet (n-UV) converted to near-infrared (NIR) emission of the aluminosilicate phosphors have achieved via Ce3+ → Tb3+ → Yb3+ resonant energy transfer (ET), enabling their potential application as down-conversion (DC) converter in Si-based solar cells. The role of Tb3+ is acting as ET bridge to connect Ce3+ and Yb3+ ion pairs. Through adjusting optimal doping concentrations, these NIR DC phosphors can exhibit excitation bands in n-UV region and strong NIR emissions.

Ginger (Zingiber officinale), the type species of Zingiberaceae, is one of the most widespread medicinal plants and spices. Here, we report a high-quality, chromosome-scale reference genome of ginger ‘Zhugen’, a traditionally cultivated ginger in Southwest China used as a fresh vegetable, assembled from PacBio long reads, Illumina short reads, and high-throughput chromosome conformation capture (Hi-C) reads. The ginger genome was phased into two haplotypes, haplotype 1 (1.53 Gb with a contig N50 of 4.68 M) and haplotype 0 (1.51 Gb with a contig N50 of 5.28 M). Homologous ginger chromosomes maintained excellent gene pair collinearity. In 17,226 pairs of allelic genes, 11.9% exhibited differential expression between alleles. Based on the results of ginger genome sequencing, transcriptome analysis, and metabolomic analysis, we proposed a backbone biosynthetic pathway of gingerol analogs, which consists of 12 enzymatic gene families, PAL, C4H, 4CL, CST, C3’H, C3OMT, CCOMT, CSE, PKS, AOR, DHN, and DHT. These analyses also identified the likely transcription factor networks that regulate the synthesis of gingerol analogs. Overall, this study serves as an excellent resource for further research on ginger biology and breeding, lays a foundation for a better understanding of ginger evolution, and presents an intact biosynthetic pathway for species-specific gingerol biosynthesis.

Lactiplantibacillus plantarum is frequently exposed to salt stress during industrial applications. Catabolite control protein (CcpA) controls the transcription of many genes, but its role in the response to salt stress remains unclear. In this study, we used transcriptome analyses to investigate differences in the logarithmic growth phases of Lactiplantibacillus plantarum ST-III and its ccpA-knockout mutant when grown with or without salt and glycine betaine (GB). The deletion of ccpA significantly affected bacterial growth under different conditions. Among the comparisons, the highest proportion of differentially expressed genes (64%) was observed in the comparison between the wild-type and ccpA mutant grown with NaCl, whereas the lowest proportion (6%) was observed in the comparison between the ccpA mutant strain cultures grown with NaCl alone or with GB together. Transcriptomic analyses showed that CcpA could regulate GB uptake, activate iron uptake, produce acetyl-CoA, and affect fatty acid composition to maintain membrane lipid homeostasis in the adaptation of high-salinity conditions. Conclusively, these results demonstrate the importance of CcpA as a master regulator of these processes in response to salt stress, and provide new insights into the complex regulatory network of lactic acid bacteria. KEY POINTS: • The absence of CcpA significantly affected growth of L. plantarum and its response to salt stress. • CcpA regulates compatible solutes absorption and ions transport to resist salt stress. • CcpA alters fatty acids composition to maintain membrane lipid homeostasis towards salt stress.

In this study, three micro/mesoporous composites with MCM-41 materials overgrowing on external surfaces of Y zeolite crystals were prepared. For the three composites, average crystal particle sizes of their zeolite components differed from each other, resulting from the different levels of alkali-treatments to the original Y zeolite before the composite synthesis. Hydroisomerization of n-dodecane (n-C12) was used to evaluate the catalytic performances of bi-porous Pt-loaded composite catalysts with similar metal-acid balances but different average zeolite crystal particle sizes, which leaded to the distinction of alkene intermediates’ journey distances inside the acid-rich micropores between two accessible Pt metal sites on three catalysts. The number of protonic sites encountered by alkene intermediates along their diffusion paths, determining the skeletal transformation frequencies, was considered to be proportional to the above-mentioned intermediates’ journey distances. Results showed that bifunctional catalysts with smaller average zeolite crystal particle sizes outperformed the catalyst containing the original Y zeolite in the regard of isomerization selectivity. This implied the significant effect of intermediates’ journey distances within the microporous arrays between two Pt sites on bifunctional behaviors of catalysts. It can be confirmed that shortening this distance within certain limits indeed contributed to inhibiting secondary reactions, including the skeletal multiple branching and cracking.

Smart near-infrared (NIR) light-responsive poly N-isopropylacrylamide (PNIPAM) nanocomposite hydrogels were prepared by incorporating sparse chemical cross-linking of small molecules. The thermo-sensitive, NIR light-responsive, toughness and strength of the pure PNIPAM, PNIPAM-Graphene oxide(GO) and PNIPAM-GO-Zirconia(ZrO2) hydrogels were invesitgated. The introduction of GO induced PNIPAM the transformation from the thermosensitive to NIR light-responsive, and the oxidized groups of GO nanosheets could physically cross-link the PNIPAM chains to increase the toughness of the hydrogel networks. The loading capability and penetration resistance of PNIPAM-GO-ZrO2 composite hydrogel was obviously improved due to that the ZrO2 powder stabilize the hydrogel networks and strengthen the hydrogen bond interaction with the amide groups of PNIPAM chains compared with that of the pure PNIPAM and PNIPAM-GO, respectively.

Constructing van der Waals heterostructures can enhance two-dimensional (2D) materials with desired properties and greatly extend the applications of the original materials. On the basis of density functional theory calculations, we verify that a blue phosphorene (BlueP)/BSe inter-layer heterostructure possesses an indirect gap and intrinsic type-II band alignment. In particular, this heterostructure is found to be a potential photocatalyst for water splitting under different pH conditions and exhibits enhanced optical properties in the visible and ultraviolet light zones. Besides, we confirm that the band gap, band edge position, and optical absorption of the BlueP/BSe heterostructure can be tailored by biaxial strain. And the tensile strain increases the optical absorption significantly over the entire energy range of visible light, which can increase the efficiency of solar energy conversion. Furthermore, we determine that adjusting the number of sublayers is another effective method to modulate the band gaps and band alignments of heterostructures. Our studies provide a promising route to design new BlueP-based vdW heterostructures and explore their potential applications in electronic and optoelectronic devices.

We demonstrated a new method by preparing a large-area graphene-oxide (GO) film on the quartz plates using the double glow plasma surface alloying technology (DGPSA). The relationship between UV photo-induced wettability and tribological performance was investigated. The results indicated that GO film exhibited the special hydrophilic-hydrophobic conversion under the ultraviolet irradiation. The wettability of GO film increased from 32° to 75° after 5 min of irradiation, indicating a photo-induced hydrophobic surface. In view that UV irradiation induced the hydrophobicity of graphene, the friction coefficient of the obtained GO film after UV irradiation is lower than that before UV irradiation and their wear-proof properties are also improved. This work aims to confirm that the GO film prepared by DGPSA can display the obvious surface hydration behaviors and the tribological properties under the UV irradiation.

The petrophysical and logging response characteristics of asphaltene carbonate reservoirs were examined based on the measurement of porosity and permeability, density, compressional and shear wave slowness, resistivity and Nuclear Magnetic Resonance transverse relaxation time (T2) of cores before and after the bitumen dissolving. The results show that (1) the asphalt can damage the pore structure of the reservoir and cause reduction of effective reservoir space and permeability; (2) with the increase of asphalt content, the compression and shear wave slowness generally decrease while the density and resistivity increase; (3) with the increase of asphalt content, the compressional wave slowness and density change less, while the shear wave slowness and resistivity change larger; and (4) the T2 values of asphalt are generally less than 3 ms, and the higher the maturity of the asphalt, the lower the T2 value. Based on these experiments, a method based on conventional and special logging methods was presented to evaluate asphalt content, effective porosity and water saturation in asphaltene carbonate reservoirs. The method has already been applied to 80 wells in the Longwangmiao Formation of the Anyue gas field in the Sichuan Basin to pick out zones rich in asphalt on the plane, which has effectively guided the selection of well location in the gas reservoir development. Key words: Sichuan Basin, Cambrian Longwangmiao Formation, asphalt, carbonate reservoir, nuclear magnetic resonance logging, petrophysical properties, logging evaluation

A practical solid-phase extraction (SPE) method coupled with liquid chromatography/tandem mass spectrometry (LC-MS/MS) has been developed for the determination of the fish anesthetic MS-222 in water. Water samples were concentrated and purified using three SPE cartridges of different specifications. Elution curves of MS-222 were constructed using various methanol-water solutions on the different cartridges, and SPE conditions were optimized in accordance with the elution curves. The mobile phase containing methanol and 0.1% formic acid solution with a linear gradient elution was utilized to separate MS-222 on a C18 column. Detection was carried out by a triple-quadrupole mass spectrometry with an electrospray ion source in positive mode. Recoveries of three MS-222 fortified levels of 0.05, 0.5 and 5 μg/L ranged of 82.6-101% with relative standard deviations (RSDs) below 9.36%. The limit of detection (LOD) and limit of quantification (LOQ) of MS-222 were 0.01 μg/L and 0.03 μg/L, respectively. This method was satisfactorily applied to the determination of MS-222 in actual water samples collected from aquatic product transportation vehicles or from the natural water catchments.

A two-dimensional (2D) metallic carbon allotrope is proposed, which consists of linearly aligned bipentagon-octagon and hexagon rings in a planar sheet. The relatively high percentage of hexagon and the regular arrangement of the polygons make it energetically more favorable than most of other predicted 2D carbon allotropes. Phonon dispersions without negative frequencies also indicate its stability. Electronic structure calculations show that its metallic nature is mainly due to the atoms shared by the pentagon, hexagon and octagon. Its lattice thermal conductivity is only about one fifth of that of graphene. Armchair- and zigzag-edged nanoribbons of this structure are also studied. The former is metallic while the latter has a small band gap due to the spin-polarized edge states. The appropriate band gap and the significantly reduced thermal conductivity suggest potential applications in thermoelectricity.

An efficient strategy for the synthesis of benzofuro[2,3- b]pyrazines was developed. These tricyclic scaffolds were formed through a multistep cascade sequence, which includes double insertion of isonitriles and chemoselective bicyclization. In this reaction, a nanopalladium was used as a recyclable catalyst. Product 3w exhibited excellent anticancer activity toward T-24 (IC

We developed a significantly improved ultra-high performance liquid chromatography-tandem mass spectrometry method for determination of 5-nitro-2-furaldehyde (NF) as a surrogate using a novel internal standard for the detection of nitrofurazone. We used 2,4-dinitrophenylhydrazine derivatization and furfural as the internal standard. Derivatization was easily performed in HCl using ultrasonic manipulation for 5 min followed by liquid extraction using ethyl acetate. The samples were concentrated and purified using reverse phase and alumina cartridges in tandem. The derivatives were separated using a linear gradient elution on a C18 column with methanol and water as the mobile phase in negative ionization mode and multiple reaction monitoring. Under the optimized conditions, the calibration curves were linear from 0.2 to 20 μg/L with correlation coefficients >0.999. Mean recoveries were 80.8 to 104.4% with the intra- and inter-day relative standard deviations

Aim This study investigated the relationship between intima-media thickness (IMT) and immune parameters in obese children from five to 16 years of age. Methods We enrolled 185 obese children with a mean age of 10.65 ± 2.10 years and 211 controls with a mean age of 10.32 ± 1.81 years. Glycometabolism, lipid metabolism, sex hormones, immune indices and carotid IMT were measured. Results Serum interleukin (IL)-6, IL-10, tumour necrosis factor (TNF)-alpha, white blood cells and common and internal carotid artery IMTs in the obese group were higher than those in the control group (p < 0.05, respectively). Bivariate correlation analysis showed that the common carotid arterial IMT was positively correlated with alanine aminotransferase, triglyceride, uric acid, apolipoprotein B, IL-6, IL-10, TNF-alpha, follicle-stimulating hormone and testosterone. Internal carotid artery IMT was positively correlated with alanine aminotransferase and follicle-stimulating hormone. Both common and internal carotid artery IMTs were inversely correlated with apolipoprotein A1 (p < 0.05, respectively). Stepwise multiple regression analysis showed that testosterone, alanine aminotransferase and TNF-alpha were the independent determinants of common carotid arterial IMT. Conclusion Tumour necrosis factor-alpha, alanine aminotransferase and testosterone were associated with intima thickening in the early life in obese children and may increase later risks of premature atherogenicity and adult cardio-cerebrovascular diseases.

Finding novel atomically thin heterostructures and understanding their electronic properties is critical for developing better nanoscale electronic and optoelectronic devices. In this work, we investigate the structural and electronic properties of arsenene/GaS van der Waals (vdW) heterostructures using first-principles calculations. Our results suggest that this heterostructure has an intrinsic type-II band alignment and an indirect band gap. Comparing the calculated band edge positions to the redox potentials of water, we identify that the arsenene/GaS vdW heterostructure is a promising photocatalyst for water splitting. Moreover, we also find that intriguing indirect–direct and semiconductor–metal transitions can be induced by strain. In particular, under certain strain, degenerate valleys of conduction band bottoms will be created, which suggests potential applications in valleytronics.

A series of single phase calcium lanthanum borates Ca3La3(BO3)5:Dy3+ (CLBD) phosphors were synthesized via conventional solid-state reaction. The introduction of Dy3+ with a preferred location on La3+ over Ca2+ site in CLB is owing to the different ionic radii and charge valent and confirmed by XRD, Rietveld refinements and photoluminescence analysis. Under ultraviolet (UV) excitation, tunable colors of high-brightness emissions were realized by controlling the Dy3+ doping concentrations. The CLBD demonstrated potential application as non-contact and self-calibration thermometer. Two different effective strategies for temperature sensing were investigated, namely, fluorescent intensity ratio (FIR) and emission decays. The FIR method was employed the fluorescence ratio of 4I15/2 → 6H15/2/4F9/2 → 6H15/2 due to the Boltzmann-like distribution of the two exited energy levels with temperature while the decay lifetimes were fitted and compared by adopting three different theoretical models: multiphonon relaxation (MR), charge transfer (CT) and transformed CT (TCT, which further consideration the relationship between CT energy and temperature). Altogether, the CLBD phosphors show promising potentials for temperature sensing.

A practical multi-residue method based on ultra-performance liquid chromatography/tandem mass spectrometry was developed for the simultaneous determination of 23 perfluorinated alkylated substances (PFASs) in water and suspended particles. Suspended particle samples were extracted with 1% formic acid-acetonitrile and cleaned by matrix solid phase dispersion extraction using a C

W-10 wt.% Cr (W-10Cr) and W-20 wt.% Cr (W-20Cr) alloys were fabricated through mechanical alloying and spark plasma sintering technology. The microstructure of W-Cr alloys was characterized by XRD, SEM, TEM. The Cr added into W-20Cr alloy remarkably improves its relative density and the microhardness from 333.5 HV to 960.7 HV. The semicoherent precipitated phase Cr-O in W-20Cr alloy enhances the boundary strength, which consequently changes the fracture mode from typical intergranular fracture to a thorough transgranular fracture. Oxidation experiments at 800 °C and 1000 °C confirmed that W-20Cr alloy shows better oxidation resistance. During the oxidation process, W-rich phase exerts adverse effect on the antioxidant property of W-Cr alloys, Cr2WO6 and CrWO4 in oxide layer help improve the oxidation resistance. During the irradiation process, the doping of Cr element reduces the irradiation damage of W matrix and protects from forming the fuzz structure.

Background To investigate the clinical and molecular characteristics of Chinese children with maturity onset diabetes of the young (MODY). Methods A total of 42 Chinese patients suspected MODY referred to our unit from 2014 to 2018 were enrolled. Mutational analysis of monogenic diabetes mellitus genes was performed by next-generation sequencing and confirmed by Sanger sequencing. Results There were 28 males (66.7%) and 14 females (33.3%) with a mean age of 9.49 ± 3.46 years (range, 1.4–15.3 years) and a mean birth weight of 3.38 ± 0.49 kg (range, 2.55–4.90 kg). Among these patients, 15 patients had polyuria, polydipsia or weight loss. Two patients (4.8%) were obese and six (14.3%) were overweight. Moreover, 13 patients (30.9%) had a family history of diabetes. Thirty variants were identified in 28 patients. Twenty-six variants in 25 patients were pathogenic or likely pathogenic genes (59.5%, 25/42), including 15 patients (60.0%, 15/25) with GCK mutation, four (16.0%, 4/25) with PAX4 mutation, three (12.0%, 3/25) with HNF4A mutation, one (4.0%, 1/25) with INS mutation, one (4.0%, 1/25) with NEUROD1 mutation and one (4.0%, 1/25) with HNF1A mutation. Nine mutations (36.0%, 9/25) were novel. There was no difference between mutation-suspected patients and MODY-confirmed patients except for a 2-h glucose increment in an oral glucose tolerance test (OGTT), while the GCK-MODY had lower glycated hemoglobin (HbA1c) and a significantly smaller 2-h glucose increment in an OGTT compared with transcription factor MODYs. The GCK-MODY was identified by incidental hyperglycemia without glycosuria. GCK-MODY without drug management and hepatocyte nuclear factor-1 alpha (HNF4A) or HNF1A-MODY with sulfonylurea therapy obtained good glucose controlling. Conclusions Mutation of the GCK gene is the most common in MODY patients in China followed by PAX4. The screening criteria can improve the cost-effectiveness of disease diagnosis and treatment. A precise molecular diagnosis would lead to optimal treatment of the patients.

Deoxynivalenol (DON) is well-known enteropathogenic mycotoxin which can alter intestinal barrier functions. Consistently, Ochratoxin A (OTA) ingestion has been found to induce intestinal injuries, including inflammation and diarrhea. However, little is known whether OTA aggravates DON-induced toxicity. This study is designed to explore the effects of OTA on DON-induced intestinal barrier function and involved mechanism. Our results showed either DON or OTA could disrupt intestinal barrier function in a time- and dose-dependent manner, as demonstrated by decreased transepithelial electrical resistance (TEER) and increased paracellular permeability to 4 kDa dextran. However, to eliminate the involvement of cell death, nonlethal concentrations of DON and OTA were used in following experiments. The nontoxic concentration of OTA was observed to aggravate DON-induced intestinal barrier dysfunction, accompanied with tight junction disruption (Claudin-3 and Claudin-4). Moreover, nontoxic concentrations of OTA aggravated DON-induced up-regulation of pro-inflammatory cytokines expression and activated nuclear factor-κB (NF-κB) in IPEC-J2 cells. Adding NF-κB inhibitor (PDTC) alleviated the aggravating effects of nontoxic concentrations of OTA on DON-induced intestinal barrier dysfunction and inflammation. These findings indicate that nontoxic concentrations of OTA promoted DON-induced barrier dysfunction via NF-κB signaling pathway. Our experiment suggests that exposure to nontoxic concentrations of toxins also poses potentially harmful effects.

The electronic structure, dielectric, piezoelectric, and nonlinear optical properties of recently synthesized polar iodate BiO(IO3) are systematically investigated by density functional theory calculations. The energy band structure shows that it is an indirect-band-gap semiconductor. The analyses of its zone-center phonon modes, it is found that there are 17A1, 18A2, 17B1, and 17 B2 optical phonon modes. The elastic stiffness tensors satisfy the Born stability restriction, indicating that this compound is mechanically stable. Importantly, the large piezoelectric and nonlinear optical susceptibilities show that polar iodate BiO(IO3) is a highly competitive piezoelectric and nonlinear optical material.

In search of half-metallic ferromagnetism, we have studied the electronic and magnetic properties of Co2VSb by using the different tools like GGA, LSDA+U and mBJ potential based on density functional theory (DFT). The compound Co2VSb is analogous to Co2VAl, Co2VSn and Co2VGa , these compounds were studied theoretically and experimentally by Buschow and Engen. We expect the similar kind of properties from Co2VSb as that of Co2VAl, Co2VSn and Co2VGa. The mBJ potential is considered to be more effective as compared to LDA and GGA which gives higher value of band gap. The theoretical lattice constant obtained from volume optimization is 6.072 A. The calculated value of energy gaps was found to be 0.20 eV, 1.00 eV and 1.30 eV for GGA, LSDA+U and mBJ respectively. Our results of band gap calculation predicts that mBJ overestimate the results of GGA, LSDA and LSDA+U.

The band-gap modulation of zigzag and armchair graphane-like SiC nanoribbons (GSiCNs) under uniaxial elastic strain is investigated using the density functional theory. The results show that band gap of both structures all decreases when being compressed or tensed. In compression, both zigzag and armchair GSiCNs are semiconductors with a direct band gap. However, in tension, the armchair GSiCNs undergo a direct-to-indirect band-gap transition but the zigzag GSiCNs still have a direct band gap. These results are also proved by HSE06 method. This implies a potential application of the graphane-like SiC nanoribbons in the future pressure sensor and optical electronics nanodevices.

Physisorption of hydrogen molecules in metal-organic frameworks (MOFs) provides a promising way for hydrogen storage, in which the van der Waals (vdW) interaction plays an important role but cannot be described by the density functional theory (DFT). Using the vdW density functional (vdW-DF) method, we perform ab initio calculations for the MOF-5 crystal with one or multiple H2 adsorbed in its primitive cell. It is found that the binding with the organic linker is much smaller than with the metal oxide corner, which limits the H2 loading. We show that this can be improved significantly (from 5.50 to 10.39 kJ/mol) by replacing the H atoms of the organic linker with F atoms which causes extra electrostatic interaction.

The thermal properties of monolayers of group-VA elements (P, As, Sb) with graphenelike buckled and black phosphorenelike puckered honeycomb structures are investigated systematically by theoretical calculations based on the phonon Peierls-Boltzmann equation. These structures are found to be thermodynamically stable with no appreciable negative frequencies in the phonon dispersion spectra. Generally, the thermal conductivity decreases as the atomic number increases. Anisotropy of relaxation time and thermal conductivity between armchair and zigzag directions is observed in the puckered structure but absent in the buckled structure. By analyzing the phase space of the thermal resistive three-phonon-scattering process, it is found that the acoustic-optical phonon gaps presented in the buckled structures have significant effects on thermal conductivity, not only affecting relative contribution from each process but also leading to a slight difference in the temperature dependence for buckled phosphorene. Our findings indicate a useful route for tuning the thermal conductivity of structurally similar materials by phonon engineering.

The photoabsorption spectra of linear double Na atomic chains with different lengths and inter-chain spacings are investigated using the time-dependent density functional theory (TDDFT) in the frequency domain. The formation and development of the collective resonances in the spectra are studied in terms of the spacing and length. With the decreasing spacing, the enhanced coupling between the chains lead to the emergence of extra peaks. For the well coupled double chains, the excitations show a single longitudinal mode but twin bimodal structure for the transverse modes. Our calculation reveals the formation and evolution of plasmon excitations in atomic nanostructures.

Understanding of the physisorption of H2 in metal-organic frameworks (MOFs) is critical to improving its performance for hydrogen storage. By using first-principles calculations employing the van der Waals density functional (vdW-DF) method which can properly describe the vdW interaction, we investigate the binding energy of H2 in MOF-5 crystal. The accuracy of this methodology is first examined and good accuracy comparable to the correlated wavefunction methods is found. Calculations for the true crystal structure show that the small fragment models used in previous calculations cannot represent well the property of the crystal. The good accuracy and the ability to deal with the true crystal structure make the vdW-DF method a good candidate for investigating hydrogen storage in MOFs.

Oxygen gas usually presents in carbon nanotube (CNT) based devices and can affect their transport properties. Here, we perform simulations for O2 adsorption on a (5, 5) CNT with a double vacancy. We first use first-principles plane-wave calculation to optimize the structures and then use single-particle Green function method to study their transport properties. It is found that an O2 can be either physisorbed or chemisorbed on the defective CNT. The physisorption has only minor effects on the transport while the chemisorption can improve it and the resulting conductance is affected by the orientation of the O2 bonding.

A new nano-TiO_2 multiplex photocatalyst codoped with Eu~(2+)and Gd~(3+)was prepared by a modified acidic sol-gel process.TEM and XRD results demonstrate that as-produced samples are anatase structure,and the crystallite size has relationship only with total doped Eu~(2+)/Gd~(3+)content and the minimum size appeares at 1% doped content.UV-Vis absorption spectra show that Eu~(3+)/Gd~(3+) codoping can enhance the visible light response of the TiO_2.The photocatalyst activity of Eu~(2+)/Gd~(3+) codoped TiO_2 is evaluated by photodegradation of methyl orange in an aqueous solution under natural light irradiation,A synergetic effect is observed due to Eu~(2+)/Gd~(3+)codoping,and the optimal doping concentration for Gd~(3+)and Eu~(2+)are in the range from 0.1% to 1.0% and 0.5% to 1.5% respectively. The relationship and function between Eu~(2+),Gd~(3+)and TiO_2 are also discussed.

The phase behavior of polystyrene (PS) degradation in toluene was investigated in a visual high-pressure reactor. The system of PS and toluene was heated from room temperature and atmospheric pressure to 350°C and 5.0 MPa. It was observed that during this process, PS dissolved quickly, and then, the system appeared to be a homogeneous phase, and PS degradation occurred in this system. With another high-pressure batch reactor, PS degradation was studied in the temperature range 275–360°C and the pressure ranges 4.5–10.5 MPa. The drop-in molecular weights in the temperature ranges and the amount of PS converted into volatile products were observed. Moreover, the effects of the temperature, pressure, and ratio of toluene to PS on the rate of PS degradation are discussed. The kinetic studies showed that the rate of PS degradation in supercritical toluene increased substantially because the degradation occurred in a homogeneous phase. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Anodization of Ti using ethylene glycol containing 0.5wt% NH4F as electrolyte resulted in ordered arrays of TiO2 nanotube with a smooth surface. Electrochemical anodization was carried out at room temperature. The microstructures and morphologies of the TiO2 nanotube were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD). A series of studies were carried out to investigate the properties of TiO2 nanotubes (anatase) for lithium anode materials and for the materials of photocatalyzing degradation of aqueous methyl orange. The results show that high density, well ordered and uniform TiO2 nanotube arrays are fabricated. TiO2 nanotube shows a comparatively reversible reaction when it is used for lithium ion battery by CV measurement. Adding H2O2 into the solution can improve the photocatalysis of TiO2 nanotube.

A series of extractants (tert-butylcalix(6)arene, tert-butylcalix(8)arene and octeacetate of tert-butylcalix(8)arene) were synthesized, and their structures were identified by IR and 1 H-NMR. The distribution behavior of ester catechins monomer in the aqueous and chloroform two-phase system containing one of calixarene was studied. The influences of different extractants, concentration of tert-butylcalix(8)arene and extraction temperature on the partition coefficients and the separation factors were investigated. The experiment results show that tert-butylcalix(8)arene is the best extractant that forms a more stable supramolecular compound with gallocatechin gallate (GCG) than with epigallocathechin gallate (EGCG) or epicatechin gallate (ECG). When the concentration of p-tert-butylcalix(8)arene is 3.79 mmol/L, the extraction temperature is 4 ℃, the partition coefficients of KGCG, KECG, KEGCG are 0.987, 0.629, 0.449, the separation factors of α1 and α2 are 1.450 and 1.596, respectively. The important factors influencing the extraction properties of calixarene are discovered to be its cavity size and hydrogen bonding.