Abstract
We present the second release of value-added catalogues of the LAMOST Spectroscopic Survey of the Galactic Anticentre (LSS-GAC DR2). The catalogues present values of radial velocity Vr, ...atmospheric parameters – effective temperature Teff, surface gravity log g, metallicity Fe/H, α-element to iron (metal) abundance ratio α/Fe (α/M), elemental abundances C/H and N/H and absolute magnitudes MV and $M_{K_{\rm s}}$ deduced from 1.8 million spectra of 1.4 million unique stars targeted by the LSS-GAC since 2011 September until 2014 June. The catalogues also give values of interstellar reddening, distance and orbital parameters determined with a variety of techniques, as well as proper motions and multiband photometry from the far-UV to the mid-IR collected from the literature and various surveys. Accuracies of radial velocities reach 5 km s−1 for the late-type stars, and those of distance estimates range between 10 and 30 per cent, depending on the spectral signal-to-noise ratios. Precisions of Fe/H, C/H and N/H estimates reach 0.1 dex, and those of α/Fe and α/M reach 0.05 dex. The large number of stars, the contiguous sky coverage, the simple yet non-trivial target selection function and the robust estimates of stellar radial velocities and atmospheric parameters, distances and elemental abundances make the catalogues a valuable data set to study the structure and evolution of the Galaxy, especially the solar-neighbourhood and the outer disc.
Summary
Background
Vitiligo is an autoimmune chronic depigmentation disorder caused by melanocyte loss. Previous studies found that CD4+CD25+ regulatory T‐cell (Treg) dysfunction was involved in the ...pathogenesis of vitiligo and that gene polymorphisms in forkhead box P3 (FOXP3) – a master regulator of Treg development and function – were associated with susceptibility to some autoimmune disorders. Therefore, we hypothesized that functional polymorphisms of the FOXP3 gene might be associated with vitiligo via dysregulation of Treg cells.
Objectives
To evaluate whether FOXP3 polymorphisms are associated with vitiligo risk.
Material and methods
In this hospital‐based case–control study of 682 patients with vitiligo and 682 vitiligo‐free age‐ and sex‐matched controls, we genotyped three single nucleotide polymorphisms (SNPs) of the FOXP3 gene – rs2232365, rs3761548 and rs5902434 – by performing polymerase chain reaction with sequence‐specific primers (PCR‐SSP).
Results
Significantly increased vitiligo risk was associated with the rs2232365 GG odds ratio (OR) 1·68, 95% confidence interval (CI) 1·17–2·39, P = 0·004 and rs3761548 AA (OR 1·82, 95% CI 1·10–3·01, P = 0·033) genotypes compared with the rs2232365 AA and rs3761548 CC genotypes. On combined analysis of these three variant alleles, we found that individuals carrying 2–6 variant alleles had significantly increased vitiligo risk (OR 1·34, 95% CI 1·08–1·66). This risk was more pronounced in the following subgroups: age > 20 years, male sex, active vitiligo, nonsegmental vitiligo and other accompanying autoimmune diseases.
Conclusions
FOXP3 gene polymorphisms contributed to vitiligo risk in a Han Chinese population.
What's already known about this topic?
Previous findings have suggested that forkhead box P3 (FOXP3) is a master regulator of regulatory T cells (Tregs) for maintaining immune tolerance and abrogating autoimmune diseases.
Dysfunction of Tregs is involved in the autoimmune mechanism of vitiligo.
FOXP3 polymorphisms negatively affect the expression and functions of FOXP3 as well as of its target genes.
What does this study add?
Our study suggests an association between FOXP3 gene polymorphisms and vitiligo susceptibility.
Often, the sources of polycyclic aromatic hydrocarbons (PAHs) in environmental media can be identified by comparing the ratios of concentrations of selected pairs of PAH congeners in the source ...emissions to the ratios in the contaminated environmental media. However, these ratios can be altered significantly due to differences in the transport of the PAH compounds in a multimedia environment. To examine such changes, a fugacity model was applied to PAH ratios in a model environment. A linear relationship between the rate of emission and the bulk media concentration was identified for each PAH compound in an environmental medium at steady state and was quantified by a receptor-to-source ratio (R RS). It was demonstrated that the R RS values of the two congeners usually differ significantly. Consequentially, PAH ratios changed remarkably from the source emissions to various environmental media. A site-specific rectification factor (RF) was defined as the ratio of the two R RS values of the paired congeners for a specific PAH ratio in a given medium, which can be applied to account for the ratio changes in a multimedia environment. The PAH ratio changes were further verified with the surface soil data collected from Tianjin, China, and the observed changes of PAH ratios were compared favorably with the model predictions. The sensitivity analysis revealed that PAH ratios of the low molecular weight compounds were less stable. The most influential parameters controlling PAH ratios were those pertaining to dry precipitation, surface-to-air diffusion, degradation in air and water, and exchange between water and sediment.
Accurate determinations of atmospheric parameters (effective temperature Teff, surface gravity log g, and metallicity Fe/H) and distances for large complete samples are of vital importance for ...various Galactic studies. We have developed a photometric method to select red giant stars and estimate their atmospheric parameters from the photometric colors provided by SkyMapper Southern Survey (SMSS) data release (DR) 1.1, using stars in common with the LAMOST Galactic spectroscopic surveys as a training set. Distances are estimated with two different approaches: one based on the Gaia DR2 parallaxes for nearby (d ≤ 4.5 kpc) bright stars and another based on the absolute magnitudes predicted by intrinsic color (g − i)0 and photometric metallicity Fe/H for distant (d > 4.5 kpc) faint stars. Various tests show that our method is capable of delivering atmospheric parameters with a precision of ∼80 K for Teff, ∼ 0.18 dex for Fe/H, and ∼0.35 dex for log g but with a significant systematic error at log g ∼ 2.3. For distances delivered from (g − i)0 and photometric Fe/H, our test with the member stars of globular clusters show a median uncertainty of 16% with a negligible zero-point offset. Using this method, the atmospheric parameters and distances of nearly one million red giant stars are derived from SMSS DR1.1. Proper motion measurements from Gaia DR2 are available for almost all of the red giant stars, and radial velocity measurements from several large spectroscopic surveys are available for 44% of these. This sample will be accessible at https://yanghuang0.wixsite.com/yangh/research.
We present a three-dimensional extinction map in the r band. The map has a spatial angular resolution, depending on latitude, between 3 and 9 arcmin and covers the entire Xuyi Schmidt Telescope ...Photometric Survey of the Galactic Anticentre (XSTPS-GAC) survey area of over 6000 deg2 for Galactic longitude 140 < l < 240 deg and latitude −60 < b < 40 deg. By cross-matching the photometric catalogue of the XSTPS-GAC with those of 2MASS and WISE, we have built a multiband photometric stellar sample of about 30 million stars and applied spectral energy distribution (SED) fitting to the sample. By combining photometric data from the optical to the near-infrared, we are able to break the degeneracy between the intrinsic stellar colours and the amounts of extinction by dust grains for stars with high photometric accuracy, and trace the extinction as a function of distance for low Galactic latitude and thus highly extincted regions. This has allowed us to derive the best-fitting extinction and distance information of more than 13 million stars, which are used to construct the three-dimensional extinction map. We have also applied a Rayleigh–Jeans colour excess (RJCE) method to the data using the 2MASS and WISE colour (H − W2). The resulting RJCE extinction map is consistent with the integrated two-dimensional map deduced using the best-fitting SED algorithm. However for individual stars, the amounts of extinction yielded by the RJCE method suffer from larger errors than those given by the best-fitting SED algorithm.
•Al2CrFeNiCoCuTix high-entropy alloy coatings were prepared by laser cladding.•Al2CrFeNiCoCuTix coatings show excellent corrosion resistance and wear resistance.•Al2CrFeNiCoCuTix coatings play a good ...protective effect on Q235 steel.•Ti element promotes the formation of a BCC structure in a certain extent.
The Al2CrFeNiCoCuTix high-entropy alloy coatings were prepared by laser cladding. The structure, hardness, corrosion resistance, wear resistance and magnetic property were studied by metallurgical microscope, scanning electron microscopy with spectroscopy (SEM/EDS), X-ray diffraction, micro/Vickers hardness tester, electrochemical workstation tribometer and multi-physical tester. The result shows that, Al2CrFeNiCoCuTix high-entropy alloy samples consist of the cladding zone, bounding zone, heat affected zone and substrate zone. The bonding between the cladding layer and the substrate of a good combination; the cladding zone is composed mainly of equiaxed grains and columnar crystal; the phase structure of Al2CrFeNiCoCuTix high-entropy alloy coatings simple for FCC, BCC and Laves phase due to high-entropy affect. Ti element promotes the formation of a BCC structure in a certain extent. Compared with Q235 steel, the free-corrosion current density of Al2CrFeNiCoCuTix high-entropy alloy coatings is reduced by 1–2 orders of magnitude, the free-corrosion potential is more “positive”. With the increasing of Ti content, the corrosion resistance of Al2CrFeCoCuNiTix high-entropy alloy coatings enhanced in 0.5mol/L HNO3 solution. Compared with Q235 steel, the relative wear resistance of Al2CrFeCoCuNiTix high-entropy alloy coatings has improved greatly; both the hardness and plasticity are affecting wear resistance. Magnetization loop shows that, Ti0.0 high-entropy alloy is a kind of soft magnetic materials.
Modern large-scale surveys have allowed the identification of large numbers of white dwarfs. However, these surveys are subject to complicated target selection algorithms, which make it almost ...impossible to quantify to what extent the observational biases affect the observed populations. The LAMOST (Large Sky Area Multi-Object Fiber Spectroscopic Telescope) Spectroscopic Survey of the Galactic anticentre (LSS-GAC) follows a well-defined set of criteria for selecting targets for observations. This advantage over previous surveys has been fully exploited here to identify a small yet well-characterized magnitude-limited sample of hydrogen-rich (DA) white dwarfs. We derive preliminary LSS-GAC DA white dwarf luminosity and mass functions. The space density and average formation rate of DA white dwarfs we derive are 0.83 ± 0.16 × 10−3 pc−3 and 5.42 ± 0.08 × 10−13 pc−3 yr−1, respectively. Additionally, using an existing Monte Carlo population synthesis code we simulate the population of single DA white dwarfs in the Galactic
anticentre, under various assumptions. The synthetic populations are passed through the LSS-GAC selection criteria, taking into account all possible observational biases. This allows us to perform a meaningful comparison of the observed and simulated distributions. We find that the LSS-GAC set of criteria is highly efficient in selecting white dwarfs for spectroscopic observations (80–85 per cent) and that, overall, our simulations reproduce well the observed luminosity function. However, they fail at reproducing an excess of massive white dwarfs present in the observed mass function. A plausible explanation for this is that a sizable fraction of massive white dwarfs in the Galaxy are the product of white dwarf–white dwarf mergers.
The extracellular signal-regulated kinase (ERK) is one of the three major types of mitogen-activated protein kinases. Previous studies showed that ERKs mediate various signaling pathways for cell ...proliferation, differentiation, survival and transformation in mammals. In the present study, we use goldfish as a model system and demonstrate that ERK kinases play important roles in promoting embryonic survival and regulate development of eye and trunk in vertebrates. ERKs are highly expressed in multiple tissues including lens epithelial cells, lens fiber cells, retina, brain, muscle and heart of adult goldfish. Injection of the dominant negative ERK mutant (DNM-ERK) into the fertilized eggs of goldfish significantly inhibited ERK activity at blastula stage, and completely blocked ERK activity at gastrula and later stages. As a result, the blastula cells were induced into apoptosis, and majority of the injected embryos were lethal at embryonic stages. At the molecular level, inhibition of ERK activity by DNM-ERKs suppressed phosphorylation of Bad at Ser-112 to promote apoptosis. Similar results were observed when MEK activity was inhibited by U0126 treatment. The survived embryos display significant abnormality in the phenotypes of both eye and trunk. Associated with the abnormality in the eye development, phosphorylation in Pax-6 and expression of HSF4 were significantly decreased and expression of the β-crystallin gene was also downregulated. These results provide novel information regarding the roles of ERKs in regulating vertebrate development.
Sanguinarine (SAG) is an alkaloid derived from the root of Sanguinaria canadensis with demonstrated anti-inflammatory, antioxidant, and antimicrobial properties. SAG is routinely used in animal feed ...as an alternative to antibiotics. However, its effect on intestinal microbiota in fish has not been clarified. Herein, we evaluated the effect of SAG on immune response, digestive enzyme activity, intestinal histology, and microbiota in Koi carp to gain a better understanding of the intestinal microbes. Three hundred fish were randomly assigned to four treatment groups consisting of basal diet alone or basal diet supplemented with three doses of SAG (50, 150, or 450 mg/kg). Blood was collected at the end of the feeding periods from 36 fish (n = 9 per treatment) and analyzed for serum parameters. Intestinal samples were collected to evaluate digestive enzyme activity, intestinal histology, mRNA expression of cytokines and bacterial community. Then remaining fish (n = 66 per treatment) were then challenged with exposure to Aeromonas hydrophila (A. hydrophila) to assess cumulative survival. The results indicated that dietary SAG decreased serum interleukin (IL)-1β in SAG-50 mg/kg (P = .0045), and IL-6 in SAG-50 mg/kg and SAG-150 mg/kg (P = .0021). The level of lysozyme (P < .0001), complement C3 (P = .0013) and glutathione peroxidase (GPx) (P < .0001) increased in all SAG-treated groups. The level of superoxide dismutase activity (SOD) increased in SAG-50 mg/kg (P < .0001), but malondialdehyde (MDA) decreased in SAG-50 mg/kg and SAG-150 mg/kg (P < .0001). Lipase activity was significantly decreased in SAG-50 mg/kg (P < .0001). No difference was observed in intestinal villus height, crypt depth, muscle thickness, and ratio of villus height to crypt depth (V/C ratio) in any group. Furthermore, SAG decreased the expression of TNF-α (P < .0001) and IL-1β (P < .0001) in the intestine. The 7-day cumulative survival increased in all SAG-treated groups (P = .0029). Moreover, low dose SAG induced changes in the β-diversity of bacterial community structure (P = .050). In conclusion, dietary SAG showed anti-inflammatory and anti-oxidative effects in koi carp. SAG enhanced non-specific immunity and survival in response to A. hydrophila infection. These SAG-mediated benefits may be associated with the structure of intestinal bacterial community.
•Dietary sanguinarine showed anti-inflammation and anti-oxidant effects in koi carp.•Sanguinarine enhanced innate immune response, and elevated the resistance against A. hydrophila infection.•Low dosage of sanguinarine induced changes in Beta-diversity of bacterial community structure (P = .050).•Sanguinarine-mediated benefits may be associated with the structure of intestinal bacterial community.
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