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Goiter is one of common endocrine diseases, and its etiology has not been fully elucidated. The changes in trace elements' levels have an important impact on the thyroid. We designed a case-control study, which involved 383 goiter cases and 383 matched controls. We measured these elements in the urine of participants by inductively coupled plasma optical emission spectrometry (ICP-OES), graphite furnace atomic absorption spectrometry (GFAAS) and As3+-Ce4+ catalytic spectrophotometry. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to select the elements into multi-element models, conditional logistic regression models were applied to analyze the association between elements and goiter risk. Bayesian kernel machine regression (BKMR) model was used to depict elements' mixtures and evaluate their joint effects. Finally, 7 elements were included in the multi-element model. We found that the concentrations of lithium (Li), strontium (Sr) and barium (Ba) had a negative effect with goiter risk, and lead (Pb) and iodine (I) showed an extreme positive effect. Additionally, compared with the lowest levels, patients with highest quartiles of I and Pb were 6.49 and 1.94 times more likely to have goiter, respectively. On the contrary, in its second and third quartiles, arsenic (As) showed a negative effect (both OR

From the view of nanostructures, hierarchical lamellar heterostructures are one of the ideal candidates for high-performance electrode materials. Herein, hierarchical lamellar Co3O4–CoMoO4 heterostructures (Co3O4–CoMoO4 HLHs) are synthesized via a facile solvothermal approach with subsequent annealing treatment. The obtained HLHs consist of lamellar parallel stacked CoMoO4 nanosheets, where Co3O4 nanoflakes uniformly grow into an array on the surface of CoMoO4 nanosheets. The formation mechanism of Co3O4–CoMoO4 HLHs can be attributed to the sequential precipitation of CoMoO4 and Co3O4 precursors during the solvothermal process. The early nucleated parallel stacked 2D nanosheets serve as templates for the growth of Co hydroxide nanoflake arrays. Owing to the structural advantage, the as-obtained Co3O4–CoMoO4 HLHs endow the constructed electrode with enhanced electrochemical activity, high specific capacity and long-term cycling stability.

In this study, a chemiluminescence immunoassay (CLIA) for human serum 25-hydroxyvitamin D (25(OH)D) was established by a competition model. In serum, more than 99% of total circulating 25(OH)D binds to protein and less than 1% of 25(OH)D is in free form (Jassil et al., 2017). Before measuring concentration of 25(OH)D in serum, a releasing procedure should be conducted. A new reagent is used to release binding 25(OH)D to free form. Streptavidin (SA) was labeled to magnetic beads by a 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) method. Biotinylated VD was used as a competitor of 25(OH)D in samples. Anti-VD antibody (aby) was labeled to horseradish peroxidase (HRP) by EDC to react with 25(OH)D and biotinylated-VD molecules. The pretreated samples or standards were added into the reaction tube with biotin-VD and anti-VD aby-HRP, free 25(OH)D in the sample competes with biotinylated VD for binding to anti-VD aby-HRP, an SA-labeled magnetic particle is added to isolate the signal-generating complex, and the signal is inversely proportional to the 25(OH)D concentration in the sample. The method established shows good thermostability and performance. The limitation of detection (LoD) is 1.43 ng/mL. The intra-assay coefficient of variation (CV) is 3.66%–6.56%, the interassay CV is 4.19%–7.01%, and the recovery rate is 93.22%–107.99%. Cross-reactivity (CR) was remarkably low with vitamin D2, vitamin D3, 1, 25-dihydroxyvitamin D3, and 1, 25-dihydroxyvitamin D2. At the same time, the cross-reaction values with 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 were 97% and 100%, respectively. The developed method shows good correlation with the total VD product from Roche and DiaSorin. 1096 clinical patient samples were measured with developed reagent kit in this study. 7 types of disease were involved, and the concentration of 25(OH)D is less than 30 ng/mL in 94.98% of patients.

The influences of different preparation conditions for surface characteristics on removing organic sulfur were studied. From BET, XRD, FTIR, DRIFTS, TG/DTA, CO 2 -TPD results, it can be seen that these preparation conditions had great influences on the pore structure, specific surface area, crystal structure and surface functional groups. The micropore volume, amorphous structure and alkalinity site strength played major roles in desulfurization process. H 2 S was oxidized by oxygen containing functional groups, such as COO, C O. H 2 O molecule could be converted into some groups, such as CH and C OH groups, and promoted the hydrolysis reaction. The strong alkalinity site was the key factor for chemical adsorption and hydrolysis. H 2 O molecule, CH, C OH groups promoted the hydrolysis reaction and COO, C O groups promoted the oxidation of H 2 S on the surface of WSB. Meanwhile, the main desulfurization process over WSB after carbonization was adsorption and it changed to hydrolysis reaction after activation on the surface of WSB. Furthermore, the reaction mechanism was investigated by DRIFTS measurement according to the change of surface functional groups.

Walnut shell-based activated carbon (WSBAC) was prepared used to simultaneously remove H2S, COS and CS2 from yellow phosphorus tail gas and closed carbide furnace tail gas. The influences of different preparation conditions (carbonization temperature, activating agent species, activating agent content, activation temperature) on the simultaneous removal efficiency of H2S, COS and CS2 were investigated. The results showed that the WSBAC carbonizated at 600 °C, then activated with 0.5 times KOH at 700 °C had the highest sulfur capacity (52.67 mgS/gWSBAC). The structure and surface properties of the catalysts were characterized by Brunauer–Emmett–Teller (BET) method, and the results showed that the high BET surface area (484.26 m2/g), high micropore volume (0.261 cm3/g) and more pore sizes of 0.3–1.8 nm were conducive to the simultaneous removal of H2S, COS and CS2. X-ray photoelectron spectroscopy results showed that the most of products on the exhausted WSBAC were S/SO4 2− species which accumulated on the WSBAC’s surface and had a negative effect on the adsorption activity.

C9H10CeO11, triclinic, P1̄ (no. 2), a = 6.9100(14) Å, b = 9.1700(18) Å, c = 10.720(2) Å, α = 69.53(3)°, β = 83.56(3)°, γ = 87.01(3)°, V = 632.3(2) Å3, Z = 2, R gt(F) = 0.0265, wR ref(F 2) = 0.0487, T = 298(2) K.

CdS quantum dots/ Boron and Nitrogen co-doped TiO2 photocatalyst emulsions were synthesized by a complexation-controlled hydrolysis method at room temperature. Boron compounds and Nitrogen compounds were added to TiO2 precursor solution, and CdS quantum dots were attached to TiO2 particles surfaces by using chemical reaction. The hybird composite photocatalysts were characterized by XRD, UV-Vis. Their photocatalytic properties were evaluated through the degradation of acid red 3R dye. The results indicate that when TiO2 emulsion add to Boron ions, Nitrogen ions, and CdS quantum dots, the photocatalytic performance of the emulsion is the best.

PbS quantum dots/ Boron and Nitrogen co-doped TiO2 photocatalyst emulsions were synthesized by a complexation-controlled hydrolysis method at room temperature. Boron compounds and Nitrogen compounds were added to TiO2 precursor solution, and PbS quantum dots were attached to TiO2 particles surfaces by using chemical reaction. The hybird composite photocatalysts were characterized by nanoparticle size analyzer. Their photocatalytic properties were evaluated through the degradation of acid red 3R dye. The results indicate that when TiO2 emulsion added to Boron ions, Nitrogen ions, and PbS quantum dots, the reflux time is 15 min, the photocatalytic performance of the emulsion is the best.

Background Sinapic acid and its esters have broad functions in different stages of seed germination and plant development and are thought to play a role in protecting against ultraviolet irradiation. To better understand the interactions between sinapic acid esters and seed germination processes in response to various stresses, we analyzed the role of the plant hormone abscisic acid (ABA) in the regulation of sinapic acid esters involved in seed germination and early seedling growth. Results We found that exogenous sinapic acid promotes seed germination in a dose-dependent manner in Arabidopsis thaliana. High-performance liquid chromatography mass spectrometry analysis showed that exogenous sinapic acid increased the sinapoylcholine content of imbibed seeds. Furthermore, sinapic acid affected ABA catabolism, resulting in reduced ABA levels and increased levels of the ABA-glucose ester. Using mutants deficient in the synthesis of sinapate esters, we showed that the germination of mutant sinapoylglucose accumulator 2 (sng2) and bright trichomes 1 (brt1) seeds was more sensitive to ABA than the wild-type. Moreover, Arabidopsis mutants deficient in either abscisic acid deficient 2 (ABA2) or abscisic acid insensitive 3 (ABI3) displayed increased expression of the sinapoylglucose:choline sinapoyltransferase (SCT) and sinapoylcholine esterase (SCE) genes with sinapic acid treatment. This treatment also affected the accumulation of sinapoylcholine and free choline during seed germination. Conclusions We demonstrated that sinapoylcholine, which constitutes the major phenolic component in seeds among various minor sinapate esters, affected ABA homeostasis during seed germination and early seedling growth in Arabidopsis. Our findings provide insights into the role of sinapic acid and its esters in regulating ABA-mediated inhibition of Arabidopsis seed germination in response to drought stress. Electronic supplementary material The online version of this article (doi:10.1186/s12870-017-1048-9) contains supplementary material, which is available to authorized users.

The aqueous solutions of lower alcohols such as methanol, ethanol, 1-propanol and 2-propanol, were studied by fluorescence spectroscopy of pyrene, defining the Py scale for polarity. Sigmoidal curves were used to fit the Py values of aqueous alcohol solutions as a function of the logarithm of water–alcohol mole ratio, i.e., log(WAR). The results from curve fittings were discussed in terms of the structural transitions of aqueous alcohol solutions, as well as the dissociation constants for alcohol– and water–pyrene complexes. The microscopic alcohol and water phases were considered to be saturated with each other, and the structures of dilute aqueous alcohol solutions were found to be more complicated than those of concentrated ones.

By using spatially resolved Raman spectroscopy together with in situ microscopy, mixed Na2SO4/MgSO4 aerosol particles with molar ratios of 1:1 and 2:1 deposited on a quartz substrate were carefully examined in their evaporation processes. Upon decreasing the relative humidity (RH), phase separations were found to occur for these droplets. For Na2SO4/MgSO4 droplets with a molar ratio of 1:1, two paths of phase separation were identified, and a large amount of small crystals were observed to disorderly distribute in the residual solutions. By comparisons with the known Raman spectra of crystals, it was concluded that the scattered crystals in the two paths were anhydrous Na2SO4 in metastable phase III and the double salt of Na2SO4· MgSO4 · 4H2O, respectively. For Na2SO4/MgSO4 aerosol droplets with a molar ratio of 2:1, only anhydrous Na2SO4 in metastable phase III precipitated with the decrease of RH. Copyright © 2008 John Wiley & Sons, Ltd.

We report on the investigation of the phase separation of individual seawater droplets in the efflorescence processes with the spatially resolved Raman system. Upon decreasing the relative humidity (RH), CaSO4.0.5H2O separated out foremost fromthe droplet atan unexpectedly high RH of approcimately 90%. Occasionally, CaSO4.2H2O substituted for CaSO4.O.5H2O crystallizing first at approximately 78% RH. Relatively large NaCI solids followed to crystallize at approximately 55% RH and led to the great loss of the solution. Then, the KMgCl3.6H2O crystallites separated out from the residual solutions, adjacentto NaCl at approximately 44% RH. Moreover, a shell structure of dried sea salt particle was found to form at low RHs, with the NaCl crystals in the core and minor supersaturated solutions covered with MgSO4 gel coating on the surface. Ultimately, the shielded solution partly effloresced into MgSO4 hydrates at very dry state (5% RH).

We consider the dynamics of locally coupled calcium oscillation systems, each cell is subjected to extracellular contaminated signal, which contains common sub-threshold signal and independent Gaussian noise. It is found that intermediate noise can enhance synchronized oscillations of calcium ions, where the frequency of noise-induced oscillations is matched with the one of sub-threshold external signal. We show that synchronization is enhanced as a result of the entrainment of external signal. Furthermore, the effect of coupling strength is considered. We find above-mentioned phenomenon exists only when coupling strength is very small. Our findings may exhibit that noise can enhance the detection of feeble external signal through the mechanism of synchronization of intercellular calcium ions.

We study the dynamic behaviour of two intracellular calcium oscillators that are coupled through gap junctions both to Ca2+ and inositol(1,4,5)-trisphosphate (IP3). It is found that synchronized anti-phase and in-phase oscillations of cytoplasmic calcium coexist in parameters space. Especially, synchronized anti-phase oscillations only occur near the onset of a Hopf bifurcation point when the velocity of IP3 synthesis is increased. In addition, two kinds of coupling effects, i.e., the diffusions of Ca2+ and IP3 among cells on synchronous behaviour, are considered. We find that small coupling of Ca2+ and large coupling of IP3 facilitate the emergence of synchronized anti-phase oscillations. However, the result is contrary for the synchronized in-phase case. Our findings may provide a qualitative understanding about the mechanism of synchronous behaviour of intercellular calcium signalling.

A series of novel all-metal sandwich species, [SbnAunSbn]m (n= 3, 4, 5, 6; m= -3, -2, -1, -2), are carefully designed and are systematically investigated in term of structure, bonding nature, stability, and potential application. These results show that [SbnAunSbn]m (n=3, 4, 5, 6; m= -3, -2, -1, -2), have local minimum values on their potential energy surfaces. For the Sb-Sb and Sb-Au bond, they are obviously covalent features, while in Au-Au, there is a typical aurophilic interaction. Furthermore, these species present expected stability owing to the positive dissociation energy, great Egap, ionization potential (IP), aromaticity and perfected mechanical stability. Interestingly, [Sb5Au5Sb5]- and [Sb6Au6Sb6]2- are aromatic, while both [Sb3Au3Sb3]3- and [Sb4Au4Sb4]2- possess conflicting aromaticity. And all the title species hold tube aromaticty and δ aromaticty. prediction The application suggests that the Sb site is favorable for absorbing CO in the units, and [Sb3Au3Sb3]3- is more suitable than others; CO is absorbed by the p-p interaction between the C and Sb atoms.

Micro-Raman and FTIR spectroscopy have been used to investigate the micrometer-sized MnSO(4) droplets. The concentration of solute within the droplet is controlled accurately by decreasing the relative humidity (RH) of the surroundings. According to the Raman spectra of MnSO(4) droplets, when the RH decreased from approximately 94% to approximately 76%, the full width of the peak at half-maximum (fwhm) of the v(1)-SO(4)(2-) band at 983 cm(-1) initially increased from 95.7 to 104.2 cm(-1). Two shoulders at approximately 993 and approximately 1002 cm(-1) occurred in the v(1)-SO(4)(2-) band at approximately 76% RH, while the v(2)-SO(4)(2-) band at 450 cm(-1) split into two bands at 442 and 462 cm(-1), indicating the formation of monodentate and bidentate contact ion pairs (CIPs) in supersaturated MnSO(4) droplets. From component band analysis of the v(1)-SO(4)(2-) band, four peaks at 983, 993, 1002, and 1010 cm(-1) were identified and assigned to the free SO(4)(2-), monodentate CIPs, bidentate CIPs, and more complex ion aggregates, respectively. Signatures of monodentate and bidentate CIPs reached their maximum values at approximately 76% and 60% RH, respectively. With further decreasing the RH, great abundance of various ion pairs presented in the droplet, corresponding the v(1)-SO(4)(2-) band steadily blue-shifted, and the fwhm increased continuously until it went through a plateau at approximately 60% RH. When the RH was between approximately 44% and 13%, the intensity of the signature from four species of ion pairs was almost invariant, corresponding to the formation of an amorphous phase of MnSO(4).2.8H(2)O. Further decreasing the RH below 13% RH, monodentate CIPs changed to bidentate ones. In the meantime, MnSO(4).2.8H(2)O was deduced to transform into another amorphous phase with a stoichiometry of MnSO(4).1.7H(2)O. This transition was also supported by the observation of the FTIR spectra according to a sharp increase of the fwhm of the v(3)-SO(4)(2-) band (at approximately 1091 cm(-1)) because of the appearance of a shoulder at 1132 cm(-1).

High signal-to-noise ratio (S/N) Raman spectra of (NH(4))(2)SO(4) droplets deposited on a quartz substrate were obtained from dilute to supersaturated states upon decreasing the relative humidity (RH). When the molar water-to-solute ratio (WSR) decreases from 16.8 to 3.2, the v(1)-SO(4)(2-) band changes very little, that is, showing a red-shift of only about 1 cm(-1) (from 979.9 to 978.8 cm(-1)) and an increase of its full width at half-maximum (fwhm) from 8.3 to 9.8 cm(-1). Other vibration modes such as v(2)- and v(4)-SO(4)(2-) bands appear almost constantly at 452 and 615 cm(-1). Such kind of a spectroscopic characteristic is different from previous observation on other cations, indicating that the interactions between SO(4)(2-) and NH(4)+ in supersaturated states are similar to those between SO(4)(2-) and H(2)O in dilute states. After fitting the Raman spectra with Gaussian functions in the spectral range of 2400-4000 cm(-1), we successfully extracted six components at positions of 2878.7, 3032.1, 3115.0, 3248.9, 3468.4, and 3628.8 cm(-1), respectively. The first three components are assigned to the second overtone of NH(4)+ umbrella bending, the combination band of NH(4)+ umbrella bending and rocking vibrations, and the NH(4)+ symmetric stretching vibration, while the latter three components are from the strongly, weakly, and slightly hydrogen-bonded components of water molecules, respectively. With a decrease of the RH, the proportion of the strongly hydrogen-bonded components increases, while that of the weakly hydrogen-bonded components decreases in the droplets. The coexistence of strongly, weakly, and slightly hydrogen-bonded water molecules must hint at a similar hydrogen-bonding network of NH(4)+, SO(4)(2-), and H(2)O to that of pure liquid water in supersaturated (NH(4))(2)SO(4) droplets.

The reliability of the solder joints is very important for lead-free solders to be applied extensively. The properties of joints have a close relationship with microstructure of the joints (W. Yang et al., J. Electr. Mater. vol. 24, no. 10, 1995). Therefore, this paper studied the microstructure evolution of Sn-3Ag-0.5Cu-XBi/Cu (where X=0-3%) solder joints after aging at varying temperatures. Sn-Ag-Cu-Bi solders have been selected for research because experiments revealed the eutectic Sn-Ag-Cu alloy to be a very promising solder in avionics and automotive applications where the solder joints are subject to numerous thermal cycles and mechanical vibrations. It has good wetting properties and forms good quality joints with copper, and also has good thermo-mechanical properties and soldering technology (C.M. Miller et al, ibid., vol. 23, no. 7, 1994), but compared with SnPb eutectic, it has higher melting temperature and high cost. It is well known that Bi has beneficial effect on mechanical properties of bulk solder when the addition of Bi is within 3%; however, there are only initial reports on the effect of Bi in solder joints, and a full understanding of Bi effects in solder applications is crucial.

Ketogulonicigenium vulgare Y25 is used in the production of vitamin C, which is responsible for the conversion reaction of l-sorbose to l-ketogulonic acid in mixed culture fermentation with Bacillus species 8. The entire genome of Ketogulonicigenium vulgare Y25 was sequenced to elucidate the metabolic pathway of sorbose and to obtained detailed insights into the growth potential of the organism. The complete genome sequence of Ketogulonicigenium vulgare Y25 was determined by the Beijing Genome Institute (Shenjun, China) using Solexa technology. A total of 221 million high-quality base pairs, giving 67.2-fold coverage of the genome, were assembled into 36 contigs using by SOAP software (http://soap.genomics.org.cn) 7. Then, the contigs were joined into 14 scaffolds using paired-end information. Gaps between contigs were closed by custom primer walks or by PCR amplification followed by DNA sequencing. The genome of Ketogulonicigenium vulgare Y25 consists of a circular chromosome and two plasmids. The chromosome is composed of 2,776,084 bp, with a G+C content of 61.72%. One plasmid contains 268,675 bp, with a G+C content of 61.35%, and the other contains 243,645 bp, with a G+C content of 62.63%. Hence, the total size of the genome is 3,288,404 bp and the average G+C content is 61.76%. There are a total of 3,290 putative open reading frames (2,807 [chromosome], 256 [pYP1], and 227 [pYP2]) using Glimmer, giving a coding intensity of 91.05%. A total of 59 tRNA genes for all 20 amino acids but tyrosine and five 16S-23S-5S rRNA operons were identified. Four genes encoding sorbose dehydrogenase were found in the chromosome. All of them were cloned and characterized. The result indicated that every one could transform l-sorbose into 2-keto-gulonic acid and required pyrroloquinoline quinine for the prosthetic groups in vitro (unpublished data). Sequence alignment analysis showed that they hadhigh homology in nucleic acid and amino acid sequences 1, 4, 9, and 10. It is estimated that multiple copies of the sorbose dehydrogenase gene can be attributed to highly efficient conversion of sorbose to 2-keto-gulonic acid. A pqqABCDE cluster of coenzyme PQQ biosynthesis has also been isolated. It shows the same arrangement of pqq genes as that in other species: a small pqqA gene with its own promoter followed by an operon with the other four genes2, 3, 5, 6. In addition, several genes encoding sorbitol dehydrogenase, sorbose reductase, sorbsone dehydrogenase, etc., were annotated in the genome. The Y25 genome sequence and its curated annotation are important assets to better understand the physiology and metabolic potential of Ketogulonicigenium vulgare and will open up new opportunities in the functional genomics of this species.