As a major component of the LAMOST Galactic surveys, the LAMOST Spectroscopic Survey of the Galactic Anticentre (LSS-GAC) aims to survey a significant volume of the Galactic thin/thick discs and halo ...for a contiguous sky area of over 3400 deg2 centred on the Galactic anticentre (|b| ≤ 30°, 150 ≤ l ≤ 210°), and obtain λλ3700–9000 low-resolution (R ∼ 1800) spectra for a statistically complete sample of ∼3 M stars of all colours down to a limiting magnitude of r ∼ 17.8 mag (to 18.5 mag for limited fields). Together with Gaia, the LSS-GAC will yield a unique data set to advance our understanding of the structure and assemblage history of the Galaxy, in particular its disc(s). In addition to the main survey, the LSS-GAC will also target hundreds of thousands objects in the vicinity fields of M 31 and M 33 and survey a significant fraction (over a million) of randomly selected very bright stars (r ≤ 14 mag) in the Northern hemisphere. During the Pilot and the first year Regular Surveys of LAMOST, a total of 1042 586 750 867 spectra of a signal-to-noise ratio S/N(7450 Å) ≥ 10 S/N(4650 Å) ≥ 10 have been collected. In this paper, we present a detailed description of the target selection algorithm, survey design, observations and the first data release of value-added catalogues (including radial velocities, effective temperatures, surface gravities, metallicities, values of interstellar extinction, distances, proper motions and orbital parameters) of the LSS-GAC.
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.
Background
Postoperative complications have a great impact on the postoperative course and oncological outcomes following major cancer surgery. Among them, infective complications play an important ...role. The aim of this study was to evaluate whether postoperative infective complications influence long‐term survival after liver resection for hepatocellular carcinoma (HCC).
Methods
Patients who underwent resection with curative intent for HCC between July 2003 and June 2016 were identified from a multicentre database (8 institutions) and analysed retrospectively. Independent risk factors for postoperative infective complications were identified. After excluding patients who died 90 days or less after surgery, overall survival (OS) and recurrence‐free survival (RFS) were compared between patients with and without postoperative infective complications within 30 days after resection.
Results
Among 2442 patients identified, 332 (13·6 per cent) had postoperative infective complications. Age over 60 years, diabetes mellitus, obesity, cirrhosis, intraoperative blood transfusion, duration of surgery exceeding 180 min and major hepatectomy were identified as independent risk factors for postoperative infective complications. Univariable analysis revealed that median OS and RFS were poorer among patients with postoperative infective complications than among patients without (54·3 versus 86·8 months, and 22·6 versus 43·2 months, respectively; both P < 0·001). After adjustment for other prognostic factors, multivariable Cox regression analyses identified postoperative infective complications as independently associated with decreased OS (hazard ratio (HR) 1·20, 95 per cent c.i. 1·02 to 1·41; P = 0·027) and RFS (HR 1·19, 1·03 to 1·37; P = 0·021).
Conclusion
Postoperative infective complications decreased long‐term OS and RFS in patients treated with liver resection for HCC.
From a multi‐institutional database, 2442 patients who underwent resection with curative intent for hepatocellular carcinoma between 2003 and 2016 were analysed retrospectively. Among them, 332 patients (13·6 per cent) had postoperative infective complications within 30 days after surgery. Multivariable Cox regression revealed that postoperative infective complications decreased long‐term overall and recurrence‐free survival after liver resection for hepatocellular carcinoma.
Complications decrease long‐term overall survival
We introduce the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) stellar parameter pipeline at Peking University – lsp3, developed and implemented for the determinations of radial ...velocity V
r and stellar atmospheric parameters (effective temperature T
eff, surface gravity log g, metallicity Fe/H) for the LAMOST Spectroscopic Survey of the Galactic Anticentre (LSS-GAC). We describe the algorithms of lsp3 and examine the accuracy of parameters yielded by it. The precision and accuracy of parameters yielded are investigated by comparing results of multi-epoch observations and of candidate members of open and globular clusters, with photometric calibration, as well as with independent determinations available from a number of external data bases, including the PASTEL archive, the APOGEE, SDSS and RAVE surveys, as well as those released in the LAMOST DR1. The uncertainties of lsp3 parameters are characterized and quantified as a function of the spectral signal-to-noise ratio (SNR) and stellar atmospheric parameters. We conclude that the current implementation of lsp3 has achieved an accuracy of 5.0 km s−1, 150 K, 0.25 dex, 0.15 dex for the radial velocity, effective temperature, surface gravity and metallicity, respectively, for LSS-GAC spectra of FGK stars of SNRs per pixel higher than 10. The lsp3 has been applied to over a million LSS-GAC spectra collected hitherto. Stellar parameters yielded by the lsp3 will be released to the general public following the data policy of LAMOST, together with estimates of the interstellar extinction E(B − V) and stellar distances, deduced by combining spectroscopic and multiband photometric measurements using a variety of techniques.
Minocycline, a second generation broad‐spectrum antibiotic, has been frequently postulated to be a “microglia inhibitor.” A considerable number of publications have used minocycline as a tool and ...concluded, after achieving a pharmacological effect, that the effect must be due to “inhibition” of microglia. It is, however, unclear how this “inhibition” is achieved at the molecular and cellular levels. Here, we weigh the evidence whether minocycline is indeed a bona fide microglia inhibitor and discuss how data generated with minocycline should be interpreted. GLIA 2016;64:1788–1794
Main Points
Minocycline is not a specific microglia inhibitor.
Minocycline has bona fide effects on neuroinflammation in vivo.
Data generated with minocycline are difficult to interpret.
This paper develops a methodology for optimizing the hydro unit commitment (HUC) for the Three Gorges Project (TGP) in China. The TGP is the world's largest and most complex hydropower system in ...operation. The objective is to minimize the total operational cost. The decision variables are the startup or shutdown of each of the available units in the system and the power releases from the online units. The mathematical formulation must take into account the head variation over the operation periods as the net head changes from hour to hour and affects power generation. Additionally, the formulation must consider the operation of 32 heterogeneous generating units and the nonlinear power generation function of each unit. A three-dimensional interpolation technique is used to accurately represent the nonlinear power generation function of each individual unit, taking into account the time-varying head as well as the non-smooth limitations for power output and power release. With the aid of integer variables that represent the on/off and operation partition statuses of a unit, the developed HUC model for the TGP conforms to a standard mixed integer linear programming (MILP) formulation. We demonstrate the performance and utility of the model by analyzing the results from several scenarios for the TGP.
Background
Dopamine (DA) is a negative modulator of gut motility. Monoamine oxidase‐B (MAO‐B) is an important metabolic enzyme degrading DA. Rasagiline, an irreversible MAO‐B inhibitor, is used to ...treat Parkinson’s disease because of its neuroprotective effect and increasing central DA. However, it is unclear whether MAO‐B exists in the colon and rasagiline increases colonic DA, thereby affecting colonic motility.
Methods
Immunohistochemistry, western blotting, enzyme activity assay, colonic motility recording, gut transit test, and high‐performance liquid chromatography‐electrochemical detection were employed in this study.
Key Results
Monoamine oxidase‐B was distributed in the colonic muscular layers including neurons and glias of rat and human. When oral treatment of rats with rasagiline for 4 weeks, in vitro colonic motility was significantly reduced, but it was greatly reversed by SCH‐23390, an antagonist of DA D1 receptor. The rasagiline‐treated rats also manifested decreased MAO‐B activity and increased DA content in the colonic muscular layer, but no alterations were detected in the protein expressions of D1 and D2 receptors, and MAO‐A and MAO‐B, as well as in the content of 5‐hydroxytryptamine and noradrenaline. Moreover, acute administration of rasagiline did not affect the colonic motility in vitro and the colonic DA level in rats, although MAO‐B activity was significantly inhibited.
Conclusions & Inferences
Monoamine oxidase‐B is abundant in the colonic muscular layer including myenteric plexus of rat and human. Long‐term administration of rasagiline can increase colonic DA thereby inhibiting colonic motility, suggesting that colonic MAO‐B could be a potential drug target for colonic dysmotility.
Monoamine oxidase‐B was distributed in the colonic muscular layers including neurons and glias of rat and human. Long‐term treatment of rasagiline significantly inhibited colonic monoamine oxidase‐B activity and increased the dopamine content, which may contribute to colonic hypomotility.
SUMMARY
Diabetes mellitus has the probability to impair the anastomotic healing and cause postesophagectomy anastomotic leakages but previous studies showed controversial results. This review aims to ...summary the impact of diabetes mellitus on the risk of anastomotic leakage after esophagectomy. We searched the PubMed and EMBASE databases to recognize English articles that met our eligibility criteria. Odds ratio with 95% confidence interval serves as the appropriate summarized statistic. Sensitivity analysis, meta-regression analysis, and publication bias tests were also performed to perceive potential bias risks. Finally, 16 observational studies with 12359 surgical patients were included. An overall analysis identified that diabetes mellitus was significantly associated with the risk of anastomotic leakage after esophagectomy (odds ratio = 1.63; 95% confidence interval = 1.25–2.12; P < 0.001). Further subgroup analysis showed a significant impact of diabetes mellitus in surgical populations from the Europe and America (odds ratio = 1.42; 95% confidence interval = 1.22–1.65; P < 0.001) but not in the Asian populations (odds ratio = 2.27; 95% confidence interval = 0.86–6.05; P = 0.1). The robustness of these estimates was confirmed by meta-regression analysis and sensitivity analysis. No significant publication bias exists between studies. In conclusion, this systematic review demonstrates that diabetes mellitus can be a significant risk factor of anastomotic leakage for patients undergoing esophagectomy. Our findings need to be further confirmed and modified by more well-designed worldwide multivariable analyses in the future.
Hydraulic fracturing has been widely employed to enhance the permeability of tight geological formations including deep geothermal reservoirs. However, due to the complex in-situ stresses, ...high-temperature conditions and heterogeneity of the formations, hydraulic fracturing under deep geothermal conditions is poorly understood to date. The aim of the current study is, therefore, to investigate the effect of reservoir depth, temperature, and sample heterogeneity during hydraulic fracturing and the influences of rock micro-structure on fracture propagation. A series of hydraulic fracturing experiments was conducted on two Australian granite types under a wide range of confining pressures from 0 to 60 MPa and temperatures from room temperature to 300 °C simulating different geothermal environments. The corresponding micro-structural effects on the rock matrix were investigated employing high-resolution CT imaging using the IMBL facility of the Australian Synchrotron. According to the results, the breakdown pressure of reservoir rock linearly increases with reservoir depth (confining pressure). However, with increasing temperature breakdown pressure linearly decreases. This corresponds to the linear reduction of tensile strength measured by high-temperature Brazilian tensile tests. In addition, CT images showed that the injection of cold water into hot rock can result in a porous zone with porosity ranging from 2 to 3% close to the wellbore due to thermally-induced inter- and intra-crystalline cracks. In this condition, fluid leak-off is high and the measured fracture aperture of the main hydraulic fracture is relatively small. Further, fracture propagation paths and apertures are mainly controlled by the stress state and the heterogeneity of the rock matrix. It was found that fractures tend to propagate along preferential paths, mainly along grain boundaries and in large quartz and biotite minerals (grain size > 0.3 mm) and minerals with pre-existing micro-cracks.
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