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The MnII(HCO3–)–H2O2 (MnII-BAP) system shows high reactivity toward oxidation of electron-rich organic substrates; however, the predominant oxidizing species and its formation pathways involved in ...

The aim of the present study was to evaluate the antitumor effects of 2,2',4'-trihydroxychalcone (7a) on the A549 human lung cancer cell line. A549 cells were treated with different concentrations of 7a for different time periods. Cells without 7a were used as the negative control group. Cell proliferation, invasion, vasculogenic mimicry (VM) formation, heterogeneous adhesion and apoptosis were measured using Cell Counting Kit-8, Transwell invasion, VM, adhesion and flow cytometric assays, respectively. In addition, the expression of related proteins was determined using western blot analysis or ELISA. The present study found that 7a had a significant inhibitory effect on the survival rate of the A549 lung cancer cells but almost no effect on BEAS-2B human lung epithelial cells or human venous endothelial cells. The migration rate, VM length, invasion rate and heterogeneous adhesion number of cells treated with 7a significantly decreased as the concentration increased, while the apoptosis rate increased. Western blot analysis showed that 7a treatment significantly increased the expression levels of E-cadherin, cleaved poly (ADP-ribose) polymerase, Bax and caspase-3 and simultaneously decreased the expression levels of metalloproteinase-2/9, Bcl-2, phosphorylated (p)-PI3K, p-AKT, p-mTOR, vascular endothelial growth factor (VEGF), E-selectin and N-cadherin. At the same time, the ELISA results showed that the level of the pro-angiogenic factor VEGF in the culture media was reduced in the presence of 7a. In addition, 7a could also reduce the nuclear NF-κB protein expression, which could inhibit the gene transcription of tumor apoptosis and metastasis-related proteins. Therefore, 7a may exert inhibitory effects on A549 cells by inhibiting cell proliferation, migration, VM formation and heterogeneous adhesion, as well as by inducing apoptosis through the suppression of the PI3K/AKT/NF-κB signaling pathway; these findings suggested that 7a may be a promising agent for the treatment of lung cancer.

Bi2+xWO6 is a cost-effective and environmentally friendly photocatalyst that shows high reactivity in the oxidation of various contaminants under visible light. However, under alkaline conditions, the reactive oxidative species in the Bi2+xWO6 system are still not clear yet. In this study, it is observed that the oxidation rates of As(III) increase with increasing pH values in the Bi2.15WO6 system. Photoluminescence and the Mott–Schottky analyses confirm that OH− promotes the separation and transfer of photogenerated electron–hole pairs over Bi2.15WO6, thus facilitating the oxidation of As(III). Electron spin resonance spectra analysis and quenching experiments rule out contributions of •OH, O2˙−, 1O2 and superoxo species to As(III) oxidation and indicate that surface –OOH and/or H2O2 are indeed the predominant species under alkaline conditions. The improved production of H2O2 by H-donors such as glucose and phenol, as well as the UV-vis diffuse reflectance and Raman analyses, further confirms the formation of surface –OOH on Bi2.15WO6 under alkaline conditions. In the dark, the significant higher oxidation rate of As(III) by H2O2–Bi2.15WO6 than that by H2O2 alone reveals that surface −OOH, instead of H2O2, plays an important role in As(III) oxidation. This study enriches our understanding of the diversity of reactive oxygen species (ROS) in the Bi2.15WO6 system and gives new insight into the mechanism involved in the oxidation of As(III) under alkaline conditions.

Bi2+xWO6 is a cost-effective and environmentally friendly photocatalyst that shows high reactivity in the oxidation of various contaminants under visible light. However, under alkaline conditions, the reactive oxidative species in the Bi2+xWO6 system are still not clear yet. In this study, it is observed that the oxidation rates of As(iii) increase with increasing pH values in the Bi2.15WO6 system. Photoluminescence and the Mott-Schottky analyses confirm that OH- promotes the separation and transfer of photogenerated electron-hole pairs over Bi2.15WO6, thus facilitating the oxidation of As(iii). Electron spin resonance spectra analysis and quenching experiments rule out contributions of •OH, O2˙-, 1O2 and superoxo species to As(iii) oxidation and indicate that surface -OOH and/or H2O2 are indeed the predominant species under alkaline conditions. The improved production of H2O2 by H-donors such as glucose and phenol, as well as the UV-vis diffuse reflectance and Raman analyses, further confirms the formation of surface -OOH on Bi2.15WO6 under alkaline conditions. In the dark, the significant higher oxidation rate of As(iii) by H2O2-Bi2.15WO6 than that by H2O2 alone reveals that surface -OOH, instead of H2O2, plays an important role in As(iii) oxidation. This study enriches our understanding of the diversity of reactive oxygen species (ROS) in the Bi2.15WO6 system and gives new insight into the mechanism involved in the oxidation of As(iii) under alkaline conditions.

The Mn

Study Design: Hospital-based retrospective study Objectives: To evaluate the pathogenetic features of traumatic spinal cord injury (TSCI) during 1999–2016 according to changed injury etiology with time, explore different characteristics of patients suffered a TSCI during 1999–2007 and 2008–2016 in Tianjin, China. Setting: Tianjin Medical University General Hospital Methods: In this study, the medical records of TSCI patients were obtained from Tianjin Medical University General Hospital (TMUGH) from 1st January 1999 to 31th December 2016. Variables were recorded, including age, gender occupation, etiology, the level of injury, America Spinal Injury Association (ASIA) impairment scale, the severity, concomitant injuries, death and its cause. To explore the differences in characteristics by etiology and by two periods, related statistical methods were used to calculate the correlation of some variables. Differences in etiology of TSCI during 1999–2016 were evaluated and differences in epidemiological characteristics were separately compared and analyzed between the 1999–2007 period and the 2008–2016 period. Results: From 1999–2016, 831 TSCI cases were identified and 96 cases were excluded from analyses. The male-to-female ratio was 2.9:1 and the mean age was 49.7±15.2 years, which changed significantly between 1999–2007 (45.1±14.2) and 2008–2016 (51.6±15.2). Traffic accidents (45.8%) were the leading cause of TSCI during the 1999–2007 period, followed by low falls (30.7%). However, the opposite result was observed during the 2008–2016 period. Significant difference was observed compared with thoracic, lumbar and sacral levels, cervical level was the most commonly affected levels and the percentage decreased to a certain degree between 1999–2007 and 2008–2016 (from 84.4% to 68.9%). The proportions of ASIA grades A, B, C, and D were 20.5%, 10.3%, 23.3%, and 45.9%, respectively. The percentage of complete tetraplegia decreased from 22.9% in 1999–2007 to 13.2% in 2008–2016, and the percentage of incomplete paraplegia increased from 9.7% to 27.9%. Conclusion: According to the changes in the epidemiological characteristics of TSCI, relevant health service, laws and regulations, preventative strategies should be readjusted to follow up the changing situation and epidemiological characteristics of TSCI.

A novel polyvinyl alcohol (PVA)-degrading strain Bacillus cereus RA23 was isolated from an oil sludge sample and environmental factors affecting its PVA degradation efficiency were optimized in detail. Inorganic nitrogen source, ammonium chloride (NH(4)Cl), was found to be the best nitrogen source and enhanced the PVA degradation rate greatly. The optimal medium for PVA biodegradation consisted of (g/L) PVA 1, NH(4)Cl 1, K(2)HPO(4) 1.6, MgSO(4)·7H(2)O 0.05, FeSO(4)·6H(2)O 0.02, CaCl(2) 0.05, NaCl 0.02. The optimal temperature and pH for PVA biodegradation by strain RA23 was 28 °C and 7.0, respectively, and 85% of 0.1% PVA was degraded after 5 days under these conditions. FTIR studies showed that the carboxylic acids (possibly including aldehyde or ketone) could be the intermediate product of PVA biodegradation. The investigation of strain RA23 for PVA degradation will provide important information to facilitate the removal of wastewater pollution in industrial zones.

Turning heterocyclic contaminants into polymers from industrial wastewater is a promising method that opens a new door for feasible and cost-effective treatment for aromatic wastewater. In this study, CuO shows the high reactivity in the catalytic oxidation of thiophene by persulfate (PS) under pH-neutral condition, and the observed rate constant (kobs) in the PS-CuO system is about 10 times of that in the PS-alone system at pH 7.0. The linear relationship between the consumed PS and the removed thiophene reveals that a complete removal of 1.0 mM thiophene from solution requires 1.11 mM PS in the PS-CuO system, indicating that thiophene has not been completely mineralized into CO2 and H2O. Quenching experiments and EPR analysis rule out contributions of O2•− and 1O2 to thiophene oxidation, and suggest that although both SO4•− and •OH contribute to thiophene oxidation to some extent, they are not the primary oxidants in the PS-CuO system at pH 7.0. Meanwhile, the presence of thiophene radical cation indicates that electron abstraction from thiophene is an important pathway in the oxidation. The produced thiophene radical cations are then polymerized into polymers. Solid characterizations further confirm that polythiophene S,S-dioxide is the primary oxidation product. The electrochemical analysis indicates that the produced polythiophene S,S-dioxide polymers show pseudocapacitive characteristics and can be used for capacitors.

Pyrite is an extensively-distributed mineral that catalyzes oxidation of As(III) to As(V) by dissolved oxygen (DO) in natural environments; however, the catalytic mechanism of pyrite under alkaline conditions is still not clear. In this study, we observed increased oxidation rates of soluble As(III) with increasing pHs under alkaline conditions (7.5-11.0). ESR analysis and quenching experiments rule out contributions of •OH, O2•- and 1O2 to As(III) oxidation, and indicate that Fe(III)-OOH and/or H2O2 are indeed the primary oxidative species at pHs 9.0 and 11.0, and Fe(IV)=O also contributes at pH 11.0. Selective oxidation of a series of organic substrates to the corresponding oxidation products confirms the presence of Fe(III)-OOH and/or Fe(IV)=O in the pyrite system in alkaline solutions or organic solvents. Although the addition of glucose apparently increases the production of H2O2 at pHs 9.0 and 11.0, such an increase does not apparently accelerate the oxidation rate of As(III), implying that H2O2 is not the predominant species in the oxidation of As(III). This study provides new insight into the oxidative species in the pyrite-DO system under alkaline conditions.

Double PWM welding power source can restrain the net side current harmonic. In order to suppress the transient when the intermediate DC link voltage fluctuation, generally adopt the method of increasing capacitor capacity, the disadvantages of this approach are: slow dynamic response, large volume, low service life, high cost of equipment. Therefore put forward a kind of double PWM welding power source based on feed-forward control power, using the power of feed-forward can effectively inhibit the intermediate DC link voltage fluctuation, based on the control method of the power system has a high power factor, good dynamic performance, simple and easy, good application prospect.

This paper accomplished a system of high-rise building’s fire monitoring system based on CAN bus. It is applied in avoiding the harm of leakage current , over current and short circuit, and protecting electric power distribution circuits and electrical equipment, thus to prevent the occurrence of electrical fire. The monitoring system can detect phase current signal and the leakage current signal, and can display real-time and alarm. It also can proceed network service and complete the distributed remote control and fault diagnosis. Practice shows that the system the characteristics of high precision, safe and reliable, low rate of false positives, easy operation and maintenance, etc .It can satisfy the demand of large high-rise building electrical fire.

The double PWM welding power supply which can inhibit network side current harmonics,in order to suppress the transient intermediate DC link voltage fluctuations in large, by increasing the DC capacitor capacity its weaknesses are: slow dynamic response, equipment of large volume,high cost, low life.This paper presented a welding power supply double PWM power based on feedforward control, voltage fluctuation suppression intermediate DC link power using feedforward strategy is feasible. Power system composed of this control method has the advantages of small size capacitor , high power factor, good dynamic performance,simple and feasible,and has application prospect.

Based on modal strain energy method, the paper discusses viscoelastic free layer damping sheet, establishes the finite element model of it and obtains the natural frequencies and loss factor. Then the paper calculates the loss factor of viscoelastic free layer damping structure with engineering empirical formula, and compares the result with that obtained by finite element method. By comparing the two results, it indicates that the finite element method is effective in analyzing this kind of problems.

Effective extraction of data association rules can provide a reliable basis for classification of stellar spectra. The concept of stellar spectrum weighted itemsets and stellar spectrum weighted association rules are introduced, and the weight of a single property in the stellar spectrum is determined by information entropy. On that basis, a method is presented to mine the association rules of a stellar spectrum based on the weighted frequent pattern tree. Important properties of the spectral line are highlighted using this method. At the same time, the waveform of the whole spectrum is taken into account. The experimental results show that the data association rules of a stellar spectrum mined with this method are consistent with the main features of stellar spectral types.

To analyze clinical efficiency and intraoperative considerations of ankle arthroscopy for ankle impingement syndrome through anterior and posterior passage.From April 2011 to April 2015, the clinical data of 17 patients diagnosed as ankle impingement syndrome were performed arthroscopy, including 12 males and 5 females, with an average age of 32.4 years (ranging from 22 to 47). Ankle arthroscopy cleaning were carried out according to clinical symptoms and radiological imaging, crashed part were cleaned too. Non steroidal anti-inflammatory drugs and intra-articular injection of sodium hyaluronate were used as conventional postoperatively treatment. AOFAS score and Ogilvie-Harris score were used to assess preoperative situation and postoperative situation.Intra-operative conditions showed 8 cases with anterior lateral impingement syndromes, 2 cases with anterior medial impingement syndromes, 2 cases with posterior impingement syndromes and 3 cases combined with anterior and posterior impingement syndromes. Distal bundle of anterior tibiofibular ligament, anterior talusfibular ligament and synovial tissue and scar tissue were cleared up during operation. Four patients were combined with concomitant articular cartilage injury, and damage area were about 1 mm×3 mm to 1.5 mm×4 mm. Microfracture treatment were performed by 1.2 mm diameter Kirschner wire. All patients were followed up from 8 to 24 months with an average of 14.3 months. AOFAS score increased from 62.3±5.20 preoperatively to 87.6±5.40 postoperatively, Ogilvie-Harris ankle score increased from 6.70±0.98 preoperatively to 12.80±1.21 postoperatively. No neurovascular damage, wound infection or wound healing problem occurred. Ankle swelling were appeared with different degrees, but disappeared at 4 to 8 weeks postoperatively.For ankle impingement syndrome patients, ankle arthroscopy through anterior with posterior passage could effectively clear up bone and soft tissue impingement. Postoperatively non-steroidal anti-inflammatory drugs and intra-articular injection of sodium hyaluronate could effectively relieve ankle pain and swollen and achieve good therapeutic effect.

This paper describes the data release of the LAMOST pilot survey, which includes data reduction, calibration, spectral analysis, data products and data access. The accuracy of the released data and the information about the FITS headers of spectra are also introduced. The released data set includes 319 000 spectra and a catalog of these objects.

Designing the mine staff management system based on the RFID technology and GIS technology. The personnel ID information can be collected by the locating substation and transmitted to monitor center by the wireless network and cables. User’s personnel ID information which is collected by the locating substation can be used to check the staff attendance and offer the rescuer some information with the trapped victims.

We report the discovery of eight new quasars in one extragalactic field (five degree centered at RA=$08^h58^m08.2^s$, Dec=$01^o32'29.7''$) with the LAMOST commissioning observations on December 18, 2009. These quasars, with $i$ magnitudes from 16.44 to 19.34 and redshifts from 0.898 to 2.773, were not identified in the SDSS spectroscopic survey, though six of them with redshifts less than 2.5 were selected as quasar targets in SDSS. Except one source without near-IR $Y$-band data, seven of these eight new quasars meet a newly proposed quasar selection criterion involving both near-IR and optical colors. Two of them were found in the 'redshift desert' for quasars ($z$ from 2.2 to 3), indicating that the new criterion is efficient for recovering the missing quasars with similar optical colors as stars. Although LAMOST met some problems during the commissioning observations, we were still able to identify other 38 known SDSS quasars in this field, with $i$ magnitudes from 16.24 to 19.10 and redshifts from 0.297 to 4.512. Our identifications imply that a substantial fraction of quasars may be missing in the previous quasar surveys. The implication of our results to the future LAMOST quasar survey is discussed.

We present preliminary analyses of spectra of quasar candidates in two Guoshoujing Telescope (GSJT, formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope - LAMOST) test fields near M 31 where one is close to the optical center of the disk and the other is towards the northeastern outskirts of the halo, obtained during the early stage of the GSJT commissioning in the last season of 2009. Both fields contain background low-redshift quasar candidates selected from the SDSS photometry. In total, 14 new quasars with redshifts up to 2 and i magnitudes between 16.7 and 19.2, are discovered, including 7 within the 2.5° central region of M 31. We briefly discuss the potential applications of these newly discovered bright quasars.

We present new quasars discovered in the vicinity of the Andromeda and Triangulum galaxies with the LAMOST during the 2010 and 2011 observational seasons. Quasar candidates are selected based on the available SDSS, KPNO 4 m telescope, XSTPS optical, and WISE near infrared photometric data. We present 509 new quasars discovered in a stripe of ~135 sq. deg from M31 to M33 along the Giant Stellar Stream in the 2011 pilot survey datasets, and also 17 new quasars discovered in an area of ~100 sq. deg that covers the central region and the southeastern halo of M31 in the 2010 commissioning datasets. These 526 new quasars have i magnitudes ranging from 15.5 to 20.0, redshifts from 0.1 to 3.2. They represent a significant increase of the number of identified quasars in the vicinity of M31 and M33. There are now 26, 62 and 139 known quasars in this region of the sky with i magnitudes brighter than 17.0, 17.5 and 18.0 respectively, of which 5, 20 and 75 are newly-discovered. These bright quasars provide an invaluable collection with which to probe the kinematics and chemistry of the ISM/IGM in the Local Group of galaxies. A total of 93 quasars are now known with locations within 2.5 deg of M31, of which 73 are newly discovered. Tens of quasars are now known to be located behind the Giant Stellar Stream, and hundreds behind the extended halo and its associated substructures of M31. The much enlarged sample of known quasars in the vicinity of M31 and M33 can potentially be utilized to construct a perfect astrometric reference frame to measure the minute PMs of M31 and M33, along with the PMs of substructures associated with the Local Group of galaxies. Those PMs are some of the most fundamental properties of the Local Group., 26 pages, 6 figures, AJ accepted

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) had been built. A telescope information service system (TISS) for LAMOST is planning to be developed, which will be used as a maintenance tool to improve the efficiency of LAMOST. In this paper, the maintenance extent of software and hardware are presented, and the standard of interface is introduced. The driving of the model and the communication between TISS and different subsystems are also analyzed. Besides, the methods of information collection, storage and display of data are shown.

Test observation of LAMOST controlled by the software Observatory Control System (OCS) had been carried out. In this paper, the process of the observation and some test are presented, and the command model and interface agent of the OCS are introduced. The driving of the model and the communication between OCS and different subsystems are also analyzed. Test for observation flow by single steps are achieved.

We present a spectroscopic catalog of 67082 M dwarfs from the LAMOST pilot survey. For each spectrum of the catalog, spectral subtype, radial velocity, equivalent width of H${\alpha}$, a number of prominent molecular band indices and the metal sensitive parameter $\zeta$ are provided . Spectral subtype have been estimated by a remedied Hammer program (Original Hammer: Covey et al. 2007), in which indices are reselected to obtain more accurate auto-classified spectral subtypes. All spectra in this catalog have been visually inspected to confirm the spectral subtypes. Radial velocities have been well measured by our developed program which uses cross-correlation method and estimates uncertainty of radial velocity as well. We also examine the magnetic activity properties of M dwarfs traced by H${\alpha}$ emission line. The molecular band indices included in this catalog are temperature or metallicity sensitive and can be used for future analysis of the physical properties of M dwarfs. The catalog is available on the website \url{http://sciwiki.lamost.org/MCatalogPilot/}., Comment: 29 pages, 9 figures,submitted to AJ