4,473 research outputs found
Ozonation of trace organic compounds in different municipal and industrial wastewaters : kinetic-based prediction of removal efficiency and ozone dose requirements
For the wide application of ozonation in (industrial and municipal) wastewater treatment, prediction of trace organic compounds (TrOCs) removal and evaluation of energy requirements are essential for its design and operation. In this study, a kinetics approach, based on the correlation between the second order reaction rate constants of TrOCs with ozone and hydroxyl radicals ((OH)-O-center dot) and the ozone and (OH)-O-center dot exposure (i.e., integral (sic)O-3(sic)dt and integral [(OH)-O-center dot]dt, which are defined as the time integral concentration of O-3 and (OH)-O-center dot for a given reaction time), was validated to predict the elimination efficiency in not only municipal wastewaters but also industrial wastewaters. Two municipal wastewater treatment plant effluents from Belgium (HB-effluent) and China (QG-effluent) and two industrial wastewater treatment plant effluents respectively from a China printing and dyeing factory (PD-effluent) and a China lithium-ion battery factory (LZ-effluent) were used for this purpose. The (OH)-O-center dot scavenging rate from the major scavengers (namely alkalinity, effluent organic matter (EfOM) and NO2-) and the total (OH)-O-center dot scavenging rate of each effluent were calculated. The various water matrices and the (OH)-O-center dot scavenging rates resulted in a difference in the requirement for ozone dose and energy for the same level of TrOCs elimination. For example, for more than 90% atrazine (ATZ) abatement in HB-effluent (with a total (OH)-O-center dot scavenging rate of 1.9 x 10(5) s(-1)) the energy requirement was 12.3 x 10(-2) kWh/m(3), which was lower than 30.1 x 10(-2) kWh/m(3) for PD-effluent (with the highest total (OH)-O-center dot scavenging rate of 4.7 x 10(5) s(-1)). Even though the water characteristics of selected wastewater effluents are quite different, the results of measured and predicted TrOCs abatement efficiency demonstrate that the kinetics approach is applicability for the prediction of target TrOCs elimination by ozonation in both municipal and industrial wastewater treatment plant effluents
ELUCID - Exploring the Local Universe with reConstructed Initial Density field III: Constrained Simulation in the SDSS Volume
A method we developed recently for the reconstruction of the initial density
field in the nearby Universe is applied to the Sloan Digital Sky Survey Data
Release 7. A high-resolution N-body constrained simulation (CS) of the
reconstructed initial condition, with particles evolved in a 500 Mpc/h
box, is carried out and analyzed in terms of the statistical properties of the
final density field and its relation with the distribution of SDSS galaxies. We
find that the statistical properties of the cosmic web and the halo populations
are accurately reproduced in the CS. The galaxy density field is strongly
correlated with the CS density field, with a bias that depend on both galaxy
luminosity and color. Our further investigations show that the CS provides
robust quantities describing the environments within which the observed
galaxies and galaxy systems reside. Cosmic variance is greatly reduced in the
CS so that the statistical uncertainties can be controlled effectively even for
samples of small volumes.Comment: submitted to ApJ, 19 pages, 22 figures. Please download the
high-resolution version at http://staff.ustc.edu.cn/~whywang/paper
Mapping the real space distributions of galaxies in SDSS DR7: I. Two Point Correlation Functions
Using a method to correct redshift space distortion (RSD) for individual
galaxies, we mapped the real space distributions of galaxies in the Sloan
Digital Sky Survey (SDSS) Data Release 7 (DR7). We use an ensemble of mock
catalogs to demonstrate the reliability of our method. Here as the first paper
in a series, we mainly focus on the two point correlation function (2PCF) of
galaxies. Overall the 2PCF measured in the reconstructed real space for
galaxies brighter than agrees with the direct
measurement to an accuracy better than the measurement error due to cosmic
variance, if the reconstruction uses the correct cosmology. Applying the method
to the SDSS DR7, we construct a real space version of the main galaxy catalog,
which contains 396,068 galaxies in the North Galactic Cap with redshifts in the
range . The Sloan Great Wall, the largest known
structure in the nearby Universe, is not as dominant an over-dense structure as
appears to be in redshift space. We measure the 2PCFs in reconstructed real
space for galaxies of different luminosities and colors. All of them show clear
deviations from single power-law forms, and reveal clear transitions from
1-halo to 2-halo terms. A comparison with the corresponding 2PCFs in redshift
space nicely demonstrates how RSDs boost the clustering power on large scales
(by about at scales ) and suppress it on
small scales (by about at a scale of ).Comment: 19 pages, 13 figure
Mapping the Real Space Distributions of Galaxies in SDSS DR7: II. Measuring the growth rate, clustering amplitude of matter and biases of galaxies at redshift
We extend the real-space mapping method developed in Shi et at. (2016) so
that it can be applied to flux-limited galaxy samples. We use an ensemble of
mock catalogs to demonstrate the reliability of this extension, showing that it
allows for an accurate recovery of the real-space correlation functions and
galaxy biases. We also demonstrate that, using an iterative method applied to
intermediate-scale clustering data, we can obtain an unbiased estimate of the
growth rate of structure , which is related to the clustering
amplitude of matter, to an accuracy of . Applying this method to the
Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7), we construct a real-space
galaxy catalog spanning the redshift range , which
contains 584,473 galaxies in the north Galactic cap (NGC). Using this data, we
infer \fss at a median redshift , which is consistent with the WMAP9
cosmology at the level. By combining this measurement with the
real-space clustering of galaxies and with galaxy-galaxy weak lensing
measurements for the same sets of galaxies, we are able to break the degeneracy
between , , and . From the SDSS DR7 data alone, we obtain the
following cosmological constraints at redshift :
, , and
, ,
, and for galaxies within
different absolute magnitude bins and , respectively
Enhancement of recombinant myricetin on the radiosensitivity of lung cancer A549 and H1299 cells
OBJECTIVE: Myricetin, a common dietary flavonoid is widely distributed in fruits and vegetables, and is used as a health food supplement based on its immune function, anti-oxidation, anti-tumor, and anti-inflammatory properties. The aim of this study was to investigate the effects of myricetin on combination with radiotherapy enhance radiosensitivity of lung cancer A549 and H1299 cells. METHODS: A549 cells and H1299 cells were exposed to X-ray with or without myricetin treatment. Colony formation assays, CCK-8 assay, flow cytometry and Caspase-3 level detection were used to evaluate the radiosensitization activity of myricetin on cell proliferation and apoptosis in vitro. Nude mouse tumor xenograft model was built to assessed radiosensitization effect of myricetin in vivo. RESULTS: Compared with the exposed group without myricetin treatment, the groups treated with myricetin showed significantly suppressed cell surviving fraction and proliferation, increased the cell apoptosis and increased Caspase-3 protein expression after X-ray exposure in vitro. And in vivo assay, growth speed of tumor xenografts was significantly decreased in irradiated mice treated with myricetin. CONCLUSIONS: The study demonstrated both in vitro and in vivo evidence that combination of myricetin with radiotherapy can enhance tumor radiosensitivity of pulmonary carcinoma A549 and H1299 cells, and myricetin could be a potential radiosensitizer for lung cancer therapy. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/579151800121063
Exploring the fate, transport and risk of Perfluorooctane Sulfonate (PFOS) in a coastal region of China using a multimedia model
Perfluorooctane Sulfonate (PFOS) and related substances have been widely applied in both industrial processes and domestic products in China. Exploring the environmental fate and transport of PFOS using modeling methods provides an important link between emission and multimedia diffusion which forms a vital part in the human health risk assessment and chemical management for these substances. In this study, the gridded fugacity based BETR model was modified to make it more suitable to model transfer processes of PFOS in a coastal region, including changes to PFOS partition coefficients to reflect the influence of water salinity on its sorption behavior. The fate and transport of PFOS in the Bohai coastal region of China were simulated under steady state with the modified version of the model. Spatially distributed emissions of PFOS and related substances in 2010 were estimated and used in these simulations. Four different emission scenarios were investigated, in which a range of half-lives for PFOS related substances were considered. Concentrations of PFOS in air, vegetation, soil, fresh water, fresh water sediment and coastal water were derived from the model under the steady-state assumption. The median modeled PFOS concentrations in fresh water, fresh water sediment and soil were 7.20ng/L, 0.39ng/g and 0.21ng/g, respectively, under Emission Scenario 2 (which assumed all PFOS related substances immediately degrade to PFOS) for the whole region, while the maximum concentrations were 47.10ng/L, 4.98ng/g and 2.49ng/g, respectively. Measured concentration data for PFOS in the Bohai coastal region around the year of 2010 were collected from the literature. The reliability of the model results was evaluated by comparing the range of modeled concentrations with the measured data, which generally matched well for the main compartments. Fate and transfer fluxes were derived from the model based on the calculated inventory within the compartments, transfer fluxes between compartments and advection fluxes between sub-regions. It showed that soil and costal water were likely to be the most important sinks of PFOS in the Bohai costal region, in which more than 90% of PFOS was stored. Flows of fresh water were the driving force for spatial transport of PFOS in this region. Influences of the seasonal change of fresh water fluxes on the model results were also analyzed. When only seasonal changes of the fresh water flow rates were considered, concentrations of PFOS in winter and spring were predicted to be higher than that under annual average conditions, while the concentrations in summer and autumn were lower. For PFOS fluxes entering the sea, opposite conclusions were drawn compared to the concentrations. Environmental risks from the presence of PFOS in fresh water were assessed for this region through comparison with available water quality criteria values. The predicted concentrations of PFOS in the Bohai coastal region provided by the model were lower than the water quality criteria published by the United States Environmental Protection Agency and Chinese researchers, while the concentrations in more than 80% of the sampling locations exceeded the European Union Water Framework Directive Environmental Quality Standards values. Seasonal variations of flow rate might cause a significant increase in environmental risks
Video-assisted thoracic bronchial sleeve lobectomy with bronchoplasty for treatment of lung cancer confined to a single lung lobe: a case series of Chinese patients
BACKGROUND: The outcomes of video-assisted thoracic bronchial sleeve lobectomy (VABSL), a minimally invasive video-assisted thoracoscopic (VATS) lobectomy, are mostly unknown in Chinese patients. OBJECTIVES: To investigate operative and postoperative outcomes of VABSL in a cases series of Chinese patients with lung cancer. METHODS: Retrospective study of 9 patients (male:female 8:1; mean age 59.4 ± 17.6 years, ranging 21–79 years) diagnosed with lung cancer of a single lobe, treated with VABSL between March 2009 and November 2011, and followed up for at least 2 months (mean follow-up: 14.17 ± 12.91 months). Operative outcomes (tumor size, operation time, estimated blood loss and blood transfusion), postoperative outcomes (intensive care unit [ICU] stay, hospitalization length and pathological tumor stage), death, tumor recurrence and safety were assessed. RESULTS: Patients were diagnosed with carcinoid cancer (11.1%), squamous carcinoma (66.7%) or small cell carcinoma (22.2%), affecting the right (77.8%) or left (22.2%) lung lobes in the upper (55.6%), middle (11.1%) or lower (33.3%) regions. TNM stages were T2 (88.9%) or T3 (11.1%); N0 (66.7%), N1 (11.1%) or N2 (22.2%); and M0 (100%). No patient required conversion to thoracotomy. Mean tumor size, operation time and blood loss were 2.50 ± 0.75 cm, 203 ± 20 min and 390 ± 206 ml, respectively. Patients were treated in the ICU for 18.7 ± 0.7 hours, and overall hospitalization duration was 20.8 ± 2.0 days. No deaths, recurrences or severe complications were reported. CONCLUSIONS: VABSL surgery is safe and effective for treatment of lung cancer by experienced physicians, warranting wider implementation of VABSL and VATS training in China
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