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We calculated empirical reddening and extinction coefficients with respect to the dust reddening map of Schlegel et al. (1998) for the Swift -UVOT passbands, using the 'star pair' method and photometric data from the UVOT Serendipitous Source Catalogue and 2MASS as well as spectroscopic data from LAMOST Data Release 7. The reddening coefficients for the UVW 2 − UVM 2, UVM 2 − UVW 1, UVW 1 − U ,  U − B , and B − V colours are −1.39, 2.08, 0.78, 0.72, and 0.84, respectively. The extinction coefficients for the UVW 2, UVM 2, UVW 1, U ,  B , and V bands are 5.60, 6.99, 4.91, 4.13, 3.41, and 2.57, respectively. The numbers are consistent with predictions by the Fitzpatrick's extinction law of R (V)  = 3.0. Temperature-dependent variations of the coefficients are found and discussed, particularly for the ultraviolet passbands. We recommend using the new reddening and extinction coefficients in future when dereddening the Swift -UVOT data. [ABSTRACT FROM AUTHOR]

2,5-Furandicarboxylic acid (FDCA) is an important renewable biotechnological building block because it serves as an environmentally friendly substitute for terephthalic acid in the production of polyesters. Currently, FDCA is produced mainly via chemical oxidation, which can cause severe environmental pollution. In this study, we developed an environmentally friendly process for the production of FDCA from 5-hydroxymethyl furfural (5-HMF) using a newly isolated strain, Raoultella ornithinolytica BF60. First, R. ornithinolytica BF60 was identified by screening and was isolated. Its maximal FDCA titer was 7.9 g/liter, and the maximal molar conversion ratio of 5-HMF to FDCA was 51.0% (mol/mol) under optimal conditions (100 mM 5-HMF, 45 g/liter whole-cell biocatalyst, 30°C, and 50 mM phosphate buffer [pH 8.0]). Next, dcaD, encoding dicarboxylic acid decarboxylase, was mutated to block FDCA degradation to furoic acid, thus increasing FDCA production to 9.2 g/liter. Subsequently, aldR, encoding aldehyde reductase, was mutated to prevent the catabolism of 5-HMF to HMF alcohol, further increasing the FDCA titer, to 11.3 g/liter. Finally, the gene encoding aldehyde dehydrogenase 1 was overexpressed. The FDCA titer increased to 13.9 g/liter, 1.7 times that of the wild-type strain, and the molar conversion ratio increased to 89.0%. [ABSTRACT FROM AUTHOR]

The impact of navigation satellite ephemeris error on satellite common-view time transfer was analyzed. The impact varies depending on the angle in view of a satellite relative to a user (elevation) and the baseline distance between 2 users. Some extents of the impact were figured out for several elevations and different baseline. As an example, results from several common-view time transfer links in China via Compass satellite were given. [ABSTRACT FROM AUTHOR]

An abstract of the article "Analysis of Pathogens and Antimicrobial Resistance in Lower Respiratory Tract Bacterial Infection," by Ying Liu and colleagues is presented.

We develop a method to estimate photometric metallicities by simultaneously fitting the dereddened colors , , , and from the SDSS with those predicted by the metallicity-dependent stellar loci. The method is tested with a spectroscopic sample of main-sequence stars in Stripe 82 selected from the SDSS DR9 and three open clusters. With 1% photometry, the method is capable of delivering photometric metallicities precise to about 0.05, 0.12, and 0.18 dex at metallicities of 0.0, −1.0, and −2.0, respectively, comparable to the precision achievable with low-resolution spectroscopy at a signal-to-noise ratio of 10. We apply this method to the re-calibrated Stripe 82 catalog and derive metallicities for about 0.5 million stars of colors mag and distances between 0.3 and 18 kpc. Potential systematics in the metallicities thus derived, due to the contamination of giants and binaries, are investigated. Photometric distances are also calculated. About 91%, 72%, and 53% of the sample stars are brighter than r = 20.5, 19.5, and 18.5 mag, respectively. The median metallicity errors are around 0.19, 0.16, 0.11, and 0.085 dex for the whole sample, and for stars brighter than r = 20.5, 19.5, and 18.5 mag, respectively. The median distance errors are 8.8%, 8.4%, 7.7%, and 7.3% for the aforementioned four groups of stars, respectively. The data are publicly available. Potential applications of the data in studies of the distribution, (sub) structure, and chemistry of the Galactic stellar populations, are briefly discussed. The results will be presented in future papers. [ABSTRACT FROM AUTHOR]

The present study investigated the pharmacodynamic role and therapeutic mechanism of demethylzeylasteral in the suppression of inflammation in a rat model of unilateral ureteral obstruction and reduction in nuclear factor (NF)-κB pathway activity. The rats in the unilateral ureteral obstruction model were treated with 30-120 mg/kg demethylzeylasteral for 8 weeks. The activities of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and caspase-3/9, and the protein expression levels of cyclooxygenase (COX)-2 and intercellular adhesion molecule-1 (ICAM-1) and NF-κB p65 were analyzed using ELISA kits and western blot analyses, respectively. Compared with the rats in the unilateral ureteral obstruction model group, demethylzeylasteral treatment markedly inhibited the increased concentrations of serum creatinine and blood urea nitrogen, urinary protein/creatinine ratio, and concentrations of high-density lipoprotein and low-density lipoprotein cholesterol, and prevented kidney damage. In addition, demethylzeylasteral inhibited the levels of TNF-α andIL-6 and suppressed the protein expression levels of COX-2 and ICAM-1 in the kidneys of the rats in the unilateral ureteral obstruction model. Demethylzeylasteral also significantly suppressed the protein expression of NF-κB p65. The results of the present study suggested that demethylzeylasteral unilateral ureteral obstruction and inhibited inflammation via inhibiting the activation of COX-2, ICAM-1 and NF-κB p65, and suppressing the activities of caspase-3/9 in rats with unilateral ureteral obstruction. [ABSTRACT FROM AUTHOR]

An aim of the experiments is to study alloying techniques of dollop-like MM, as-cast and extruded Mg-MM master alloy in die casting AZ91D magnesium alloy at conventional cold chamber die casting temperature. The as-cast AZ91D-1.2wt%MM alloys were prepared and MM was added by different way at 720°C. The results showed that the efficiency of alloying achieved less than 50% within 30 min when dollop-like MM was added. When MM was added by as-cast and extruded Mg-21wt%MM master alloy, the efficiency of alloying was improved significantly. The microstructure and analytical studies were carried out using optical microscopy and differential scanning calrimetry (DSC). Testing results showed the Mg-MM master alloy could melt easily down at die casting temperature because Mg-RE phases with lower melting point were formed. The grain refining efficiency of the master alloy was improved by extrusion. The improvement could be attributed to the decrease in Mg-RE particle size and increase in the number of nucleating sizes for Mg. Then die-casting AZ91D-0.44wt%MM test bars were produced with addition of extruded Mg-21wt%MM master alloy and the efficiency of alloying was around 80%. [ABSTRACT FROM AUTHOR]

Interstellar extinction in ultraviolet is the most severe in comparison with optical and infrared wavebands and a precise determination plays an important role in correctly recovering the ultraviolet brightness and colors of objects. By finding the observed bluest colors at the given effective temperature and metallicity range of dwarf stars, stellar intrinsic colors, , , , and , are derived according to the stellar parameters from the LAMOST spectroscopic survey and photometric results from the GALEX and APASS surveys. With the derived intrinsic colors, the ultraviolet color excesses are calculated for about 25,000 A- and F-type dwarf stars. Analysis of the color excess ratios yields the extinction law related to the GALEX UV bands: ENUV,B/EB,V = 3.77, EFUV,B/EB,V = 3.39, and EFUV,NUV/EB,V = −0.38. The results agree very well with previous works in the NUV band and in general with the extinction curve derived by Fitzpatrick (1999) for RV = 3.35. [ABSTRACT FROM AUTHOR]

We present a three-dimensional modeling of the Milky Way dust distribution by fitting the value-added star catalog of the LAMOST spectral survey. The global dust distribution can be described by an exponential disk with a scale length of 3192 pc and a scale height of 103 pc. In this modeling, the Sun is located above the dust disk with a vertical distance of 23 pc. Besides the global smooth structure, two substructures around the solar position are also identified. The one located at 150° < l < 200° and −5° < b < −30° is consistent with the Gould Belt model of Gontcharov, and the other one located at 140° < l < 165° and 0° < b < 15° is associated with the Camelopardalis molecular clouds. [ABSTRACT FROM AUTHOR]

We report deep spectroscopy of 10 planetary nebulae (PNe) in the Andromeda Galaxy (M31) using the 10.4 m Gran Telescopio Canarias (GTC). Our targets reside in different regions of M31, including halo streams and the dwarf satellite M32, and kinematically deviate from the extended disk. The temperature-sensitive [O iii] λ4363 line is observed in all PNe. For four PNe, the GTC spectra extend beyond 1 μm, enabling the explicit detection of the [S iii] λ6312 and λλ9069, 9531 lines and thus determination of the [S iii] temperature. Abundance ratios are derived and generally consistent with AGB model predictions. Our PNe probably all evolved from low-mass (<2 M☉) stars, as analyzed with the most up-to-date post-AGB evolutionary models, and their main-sequence ages are mostly ∼2–5 Gyr. Compared to the underlying, smooth, metal-poor halo of M31, our targets are uniformly metal rich ([O/H] ≳ −0.4), and seem to resemble the younger population in the stream. We thus speculate that our halo PNe formed in the Giant Stream’s progenitor through extended star formation. Alternatively, they might have formed from the same metal-rich gas as did the outer-disk PNe but were displaced into their present locations as a result of galactic interactions. These interpretations are, although speculative, qualitatively in line with the current picture, as inferred from previous wide-field photometric surveys, that M31's halo is the result of complex interactions and merger processes. The behavior of the N/O of the combined sample of the outer-disk and our halo/substructure PNe signifies that hot bottom burning might actually occur at <3 M☉ but careful assessment is needed. [ABSTRACT FROM AUTHOR]

We present deep spectroscopy of planetary nebulae (PNe) that are associated with the substructures of the Andromeda Galaxy (M31). The spectra were obtained with the Optical System for Imaging and low-intermediate-Resolution Integrated Spectroscopy spectrograph on the 10.4 m Gran Telescopio Canarias. Seven targets were selected for the observations, three in the Northern Spur and four associated with the Giant Stream. The most distant target in our sample, with a rectified galactocentric distance 100 kpc, was the first PN discovered in the outer streams of M31. The [O iii] λ4363 auroral line is well detected in the spectra of all targets, enabling electron temperature determination. Ionic abundances are derived based on the [O iii] temperatures, and elemental abundances of helium, nitrogen, oxygen, neon, sulfur, and argon are estimated. The relatively low N/O and He/H ratios, as well as abundance ratios of α-elements, indicate that our target PNe might belong to populations as old as ∼2 Gyr. Our PN sample, including the current seven and the previous three observed by Fang et al., have rather homogeneous oxygen abundances. The study of abundances and the spatial and kinematical properties of our sample leads to the tempting conclusion that their progenitors might belong to the same stellar population, which hints at a possibility that the Northern Spur and the Giant Stream have the same origin. This may be explained by the stellar orbit proposed by Merrett et al. Judging from the position and kinematics, we emphasize that M32 might be responsible for the two substructures. Deep spectroscopy of PNe in M32 will help to assess this hypothesis. [ABSTRACT FROM AUTHOR]