Research on Classification Algorithm of Silicon Single-Crystal Growth Temperature Gradient Trend Based on Multi-Level Feature Fusion.

In the process of silicon single-crystal preparation, the timely identification and adjustment of abnormal conditions are crucial. Failure to promptly detect and resolve issues may result in a substandard silicon crystal product quality or even crystal pulling failure. Therefore, the early identification of abnormal furnace conditions is essential for ensuring the preparation of perfect silicon single crystals. Additionally, since the thermal field is the fundamental driving force for stable crystal growth and the primary assurance of crystal quality, this paper proposes a silicon single-crystal growth temperature gradient trend classification algorithm based on multi-level feature fusion. The aim is to accurately identify temperature gradient changes during silicon crystal growth, in order to promptly react to early growth failures and ensure the stable growth of high-quality silicon single crystals to meet industrial production requirements. The algorithm first divides the temperature gradient trend into reasonable categories based on expert knowledge and qualitative analysis methods. Then, it fuses the original features of actual production data, shallow features extracted based on statistical information, and deep features extracted through deep learning. During the fusion process, the algorithm considers the impact of different features on the target variable and calculates mutual information based on the difference between information entropy and conditional entropy, ultimately using mutual information for feature weighting. Subsequently, the fused multi-level feature vectors and their corresponding trend labels are input into a Deep Belief Network (DBN) model to capture process dynamics and classify trend changes. Finally, the experimental results demonstrate that the proposed algorithm can effectively predict the changing trend of thermal field temperature gradients. The introduction of this algorithm will help improve the accuracy of fault trend prediction in silicon single-crystal preparation, thereby minimizing product quality issues and production interruptions caused by abnormal conditions.

[Source Analysis and Health Risk Assessment of PAHs in PM2.5, Lüliang City].

To investigate the seasonal variation, health risks, and potential sources of polycyclic aromatic hydrocarbons(PAHs) in PM2.5 in the Lüliang area, PM2.5 samples were collected in Lishi District(downtown area) and Xiaoyi City(suburban area) from October 23, 2018 to July 1, 2019, and the concentrations of 14 PAHs were determined using gas chromatography-mass spectrometry(GC-MS). The annual average concentration of PAHs was 95.50 ng·m-3, and the concentration of 5-6 ring PAHs was mainly(49.7%), with 3 ring PAHs accounting for a relatively low proportion(8.3%).The concentration of PAHs in Lüliang City showed a seasonal pattern of winter>autumn>spring>summer. The results of the ILCRs model and Monte Carlo simulation showed that the toxicity of PAHs in Lüliang City followed the rule of adults>youth>children. Except in summer, the ILCRs values in the Lishi area were between 10-6 and 10-4, much higher than those in Xiaoyi City, indicating that there was a high potential risk of polycyclic aromatic hydrocarbons in the urban area. Through the characteristic ratio method and positive matrix factorization(PMF), it was shown that the PAHs in Lüliang City were mainly from the combustion of coal and biomass(61.9%) and vehicle exhaust emissions(38.1%). Based on the backward trajectory and potential source factor contribution analysis model, it was determined that the potential sources of PAHs in Lüliang City were mainly distributed in southern Shanxi, northern Shaanxi, and western Inner Mongolia.

Menthol induces apoptosis and inhibits proliferation and migration of nonsmall cell lung carcinoma in vitro and in vivo through Akt pathway.

BACKGROUND: About 40% of nonsmall cell lung cancers (NSCLCs) have already progressed in an advanced stage at the time of diagnosis. Development of effective prevention and therapy approaches against NSCLC is critical for reducing mortality. As a fundamental ingredient of peppermint oil, menthol has been demonstrated to possess an antitumor activity in several types of carcinomas. However, the potential role of menthol on NSCLC has not been reported. The present study aims to investigate the effect and underlying mechanism of menthol on proliferation, apoptosis, and mobility of human lung adenocarcinoma. METHODS: Cell apoptosis was examined by MTT and flow cytometry. The motility of cells was determined by Transwell assay. Western blot analysis was performed to determine expression level of proteins. In vivo model of nude mice was established for evaluating the influence of menthol on tumorigenicity of A549 cells. The expression lentiviral vector of Akt was established in NSCLC cells for further verifying the inhibiting effect of menthol on survival and mobility of NSCLC cells via Akt pathway. RESULTS: The results showed that menthol promoted A549 cell apoptosis, suppressed cell proliferation, and motility by altering the phosphorylated protein level of Akt. Menthol enhanced the expression level of Bax while decreasing expression of Bcl-2, Caspase-3, and MMPs proteins. In vivo experiments suggested that menthol exhibited an inhibitory effect in tumor growth on xenografts. These results were further validated in Akt over-expressed A549 and H1299 cells. CONCLUSIONS: Menthol could display an inhibitory effect on NSCLC cells through Akt signaling pathway, making it a potential target for NSCLC treatment.

Emission factors and source profiles of VOCs emitted from coke production in Shanxi, China.

Coking plants in China generate a substantial amount of volatile organic compounds (VOCs). The emission factors (EFs) of VOCs from coking plants are not well known, and thus, this study characterized the VOCs in the emissions from four coking plants in Shanxi, China. The EFs of VOCs from different stages of the coking process were calculated, and coal charging exhibited the highest EFs of VOCs, followed by the flue gases from combustion of coke oven gas, wastewater treatment, coke pushing and chemical byproduct recycling. The VOCs in emissions differed by coking process. Alkanes, aromatics and alkenes were the main VOCs emitted during the coking, wastewater treatment and chemical byproduct recycling processes, respectively. To effectively control the contribution of VOCs from coking processes to secondary organic aerosols and ozone formation, attention should be given to wastewater treatment and coal loading processes. The mean annual weight of VOCs emitted from coking plants in China from 2019 to 2021 was estimated to be 32.91 Gg with coking, chemical byproduct recycling, and wastewater treatment processes accounting for 91.34%, 7.85%, and 0.80% of total VOCs, respectively. An uneven spatial distribution of VOCs emissions in China was identified, with Shanxi, Shaanxi, Hebei, Inner Mongolia and Shandong being the largest contributors.

Characteristics and source apportionment of water-soluble inorganic ions in atmospheric particles in Lvliang, China.

Seasonal atmospheric particulate matter samples with different particle sizes (< 2.5 µm [PM2.5], 2.5-5 µm [PM2.5-5], 5-10 µm [PM5-10], and 10-100 µm [PM10-100]) were collected to analyze the mass concentration and distribution characteristics of nine water-soluble ions (WSIs; F-, Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+, and Ca2+) in Lvliang in China. The results of chemical composition analysis indicated that the average concentration of total WSIs was 29.08 µg·m-3 and accounted for 40.45% of PM2.5, 80.99% of which was attributable to SO42-, NH4+, and NO3-; the concentration demonstrated obvious distribution characteristics. NO3- and NH4+ primarily exist as NH4NO3 and (NH4)2SO4, respectively, in fine particles but as NaNO3 and NH4Cl, respectively, in coarse particles. The PM2.5 was alkaline overall, and K+ and NH4+ caused the highest RC/A values in autumn. Stationary sources contribute more to WSIs in particulates than mobile sources. The secondary transformation degree of SO2 was higher than that of NOx, especially in fine particles. The positive matrix factorization (PMF) and potential source contribution function (PSCF) models were combined to determine the sources of WSIs in PM2.5. Through use of the PMF model, five source factors were categorized: secondary aerosols (43.0%), biomass combustion (21.7%), coal combustion (17.6%), dust (10.9%), and vehicular traffic (6.8%). The results of the PSCF model suggested that the transport of pollutants from Shanxi, northwestern Shaanxi, Gansu, Inner Mongolia and Henan, had the greatest effect on air quality in Lvliang.

KIF15 upregulation promotes leiomyosarcoma cell growth via promoting USP15-mediated DEK deubiquitylation.

Kinesin Family Member 15 (KIF15) is a plus end-directed microtubule motor, which exerts complex regulations in cancer biology. This study aimed to explore the functional role of KIF15 in leiomyosarcoma (LMS). Bioinformatic analysis was carried out using data from The Cancer Genome Atlas (TCGA)-Sarcoma (SARC). LMS cell lines SK-UT-1 and SK-LMS-1 were used as in vitro cell models. Results showed that LMS patients with high KIF15 expression had significantly worse survival than the low KIF15 expression counterparts. KIF15 knockdown slowed, while KIF15 overexpression increased the proliferation of SK-UT-1 and SK-LMS-1 cells. Co-IP assay confirmed mutual interaction between endogenous KIF15 and DEK (encoded by DEK proto-oncogene). KIF15 knockdown facilitated DEK degradation, while KIF15 overexpression slowed DEK degradation. In ubiquitination assay, a significant increase in DEK polyubiquitylation was observed when KIF15 expression was suppressed. USP15 physically interacted with both DEK and KIF15 in the cells. USP15 knockdown decreased DEK protein stability and canceled KIF15-mediated DEK stabilization. USP15 overexpression enhanced DEK stability, the effect of which was impaired by KIF15 knockdown. USP15 overexpression reduced DEK polyubiquitination. USP15 knockdown increased DEK polyubiquitination and canceled the effect of KIF15 overexpression on reducing DEK polyubiquitination. DEK overexpression enhanced the proliferation of SK-UT-1 and SK-LMS-1 cells. DEK knockdown decreased cell proliferation and canceled the effect of KIF15 overexpression on cell proliferation. In conclusion, this study revealed a novel mechanism that KIF15 enhances LMS cell proliferation via preventing DEK protein from degradation by increasing USP15 mediated deubiquitylation.

Characterization and emission factors of carbonaceous aerosols originating from coke production in China.

Coking is a substantial source of carbonaceous aerosols in China, but the emission characteristics and pollution levels of coking-produced organic carbon (OC) and elemental carbon (EC) remain unknown, causing considerable uncertainty in emission estimates. In this study, the emission factors of OC (EFOC) and EC (EFEC) of typical coking plants in Shanxi, China, were measured. The measured EFEC and EFOC from fugitive emissions (7.43 and 9.54 g/t) were significantly higher than those from flue gas (1.67 and 3.71 g/t). The technological conditions of coke production affect the emissions of OC and EC. For example, the total emissions from coke plants that use 3.2-m-high coke ovens were greater than those from plants that use 4.3- and 6-m-high ovens. The EFOC and EFEC for plants conducting stamp charging were considerably higher than those for plants using top charging. The stable carbon isotopes of total carbon (δ13CTC), OC (δ13COC), and EC (δ13CEC) for fly ash during coking were -23.74‰ to -24.17‰, -23.32‰ to -23.87‰, and -23.84‰ to -24.14‰, respectively, and no clear isotopic fractionation was found during coke production. Different EC/OC ratios from different emission pathways and the carbon isotope signature of coke production should be considered when investigating the sources of carbonaceous aerosols. The total estimated EC and OC emissions from coke production in China were 3.93 and 5.72 Gg in 2017, and Shanxi, Hebei, and Shaanxi made the largest contributions.

[Characteristics, Sources, and Health Risks of Elements in PM2.5 in Shanxi University Town].

In order to investigate the pollution characteristics and sources of elements in PM2.5 in the Shanxi University Town in 2017, an energy dispersive X-ray fluorescence spectrometer (ED-XRF) was used to analyze 21 kinds of elements in PM2.5 samples. A health risk assessment was conducted for Mn, Zn, Cu, Sb, Pb, Cr, Co, and Ni. The main sources of elements were identified by the principal component analysis (PCA) and positive matrix factorization (PMF). The results found that, among the 21 kinds of elements in PM2.5 in Shanxi University Town, the mass concentration of Ca was the highest, followed by Si, Fe, Al, S, K, and Cl. These seven elements accounted for 95.71% of the total element concentrations. The concentration of Cr exceeded the annual average concentration limit of ambient air quality standards in China by 104 times. The concentration of Ca in PM2.5 was the highest in spring, summer, and winter, while in autumn the concentration of S was the highest. Mn was the element that had non-carcinogenic risks to the three population types, and the level of risks were in the order of children > adult men > adult women. Cr and Co had tolerable carcinogenic risks, and the risk levels were in the order of adult men > adult women > children. The main sources of elements in PM2.5 in Shanxi University Town in 2017 were natural mineral dust, urban dust, coal combustion, and traffic.

Alginate Microparticle Arrays as Self-Polishing Bio-Fouling Release Coatings.

Biofouling is a severe problem of any water borne structure. Since the ban of tin-organic compounds and expected bans of other poisonous chemical formulations in the near future, replacement of these compounds are sought. This study investigates antibiofouling properties of micro- and nanostructured alginate layer films. Alginate is a natural product from brown algae and was in this study electro-sprayed and crosslinked with divalent calcium and copper ions to produce homogeneous micro- and nanoparticles. These calcium- and copper-alginate particles were assembled into micro- and nanostructured layer films and the antifouling properties of these low elastic modulus, hydrophilic, biodegradable system were evaluated with the microalgae chlorella. Comparison with pristine glass slides, smooth copper- and calcium alginate bulk films was performed. The comparison shows less biofouling for smooth bulk films compared to micro-nanostructured alginate, while all alginate systems are less bio-fouled on long timescales compared to pristine glass.

Interdependent nitric oxide and hydrogen peroxide independently regulate the coix seed oil-induced triterpene acid accumulation in Ganoderma lingzhi.

Recent progress has been made in adding exogenous vegetable oils in culture media to promote bioactive metabolite production in several medicinal mushrooms, but the mechanism is still unclear. In this study, we found that the vegetable oil coix seed oil (CSO) could induce the biosynthesis of triterpene acids (TAs) and also significantly increase cytoplasmic nitric oxide (NO) and hydrogen peroxide (H2O2) concentrations in the mycelium of Ganoderma lingzhi. The change in TA biosynthesis caused by CSO could be reversed by adding NO scavenger or H2O2 scavenger, and adding NO scavenger or H2O2 scavenger resulted in the reduction of the cytoplasmic H2O2 or NO concentration under CSO treatment, respectively. Moreover, adding NO scavenger or H2O2 scavenger reversed TA biosynthesis, which could be rescued by H2O2 or NO donor, respectively. Taken together, our study indicated that both NO and H2O2 were involved in the regulation of TA biosynthesis, and CSO-activated NO and H2O2 were interdependent but independently regulated the TA biosynthesis under CSO treatment in G. lingzhi.

Magnetically-propelled hydrogel particle motors produced by ultrasound assisted hydrodynamic electrospray ionization jetting.

One of the most promising future applications of hydrogels is drug delivery. The hydrogels act as a biomedical cargo model to reach the target and release drugs to cure diseases. This application requires no side effects of the hydrogel and the ability to pass through porous media (e.g. membranes, interstitial tissue etc.) with nanoscaled channels. At the same time, the hydrogel must be mass-producible in an economic way. In this work, we show that hydrodynamic electrospray ionization jetting combined with ultrasound can fulfill these high requirements. This method can produce mucoadhesive micro-/nano-particles, which are small enough to pass through the gastrointestinal epithelium. The average size of the produced particles is exactly predictable by controlling the spraying distance, spraying mode, alginate concentration, ultrasound bath frequency and counter electrode shape. These micro-/nano-particles are loaded with biocompatible magnetite nanoparticles, and propelled by a rotating magnetic field between 5 to 20 m T and a frequency from 1 Hz to 100 Hz. These rotating micro-/nano-particle motors perform directional motion in solution, offering a promising possibility for magnetically controlled drug delivery.

[Intervention with Schistosoma japonicum cysteine protease inhibitor for treatment of lipopolysaccharide-induced sepsis in mice].

OBJECTIVE: To observe the effect of Schistosoma japonicum cysteine protease inhibitor (rSjCystatin) for treatment of lipopolysaccharide (LPS)-induced sepsis in mice. METHODS: After a week of adaptive feeding, 54 BALB/c mice were randomly divided into normal control group (group A), sepsis group (group B), and rSjCystatin intervention group (group C). The mice in group A received an intraperitoneal injection of PBS (100 µL), and those in groups B and C were injected with PBS (100 µL) containing LPS (10 mg/kg); the mice in group C were also intraperitoneally injected with 25 µg sjCystatin in 100 µL PBS 30 min after LPS injection. From each group, 10 mice were randomly selected 24 h after PBS or LPS injection for detecting serum levels of TNF-α, IL-6, and IL-10 using ELISA and the levels of ALT, AST, BUN, and Cr using automatic biochemical analyzer; the pathological changes in the liver, lung and kidney were observed with HE staining. The remaining 8 mice in each group were used for observing the changes in the general condition and the 72-h survival. RESULTS: The 72-h survival rates of the mice was 100% in group A, 0 in group B, and 36% in group C, showing a significant difference among the 3 groups (P<0.05). Compared with those in group A, the mice in group B exhibited obvious liver, lung, and renal pathologies with increased levels of ALT, AST, BUN, Cr, IL-6, and TNF-α (P<0.05). Treatment with sjCystatin significantly lessened LPS-induced organ pathologies, lowered the levels of liver and renal functional indexes and the pro-inflammatory cytokines, and increased the serum level of IL-10 in the mice (P<0.05). CONCLUSION: SjCystatin can produce a significant therapeutic effect on sepsis induced by LPS in mice.

NFκB mediated elevation of KCNJ11 promotes tumor progression of hepatocellular carcinoma through interaction of lactate dehydrogenase A.

It has been well documented that changes in ion fluxes across cellular membranes is fundamental in maintaining cellular homeostasis. Dysregulation and/or malfunction of ion channels are critical events in the pathogenesis of diverse diseases, including cancers. In this study, we focused on the study of K+ channels in hepatocellular carcinoma (HCC). By data mining TCGA cohort, the expression of 27 K+ channels was investigated and KCNJ11 was identified as a key dysregulated K+ channels in HCC. KCNJ11 was differentially expressed in HCC and predicted a poor prognosis in HCC patients. Inhibition of NFκB signaling suppressed KCNJ11 expression in HCC cells. Knockdown of KCNJ11 expression inhibited cell proliferation, promoted cell apoptosis, and reduced cell invasive capacity. Mechanistically, we found that KCNJ11 promotes tumor progression through interaction with LDHA and enhancing its enzymatic activity. Pharmacological inhibition of LDHA largely compromised the oncogenic function of KCNJ11 in cell proliferation, cell apoptosis, and cell invasion. Collectively, our data, as a proof of principle, demonstrate that KCNJ11 acts as an oncogene in HCC though forming a complex with LDHA and suggest that targeting KCNJ11 can be developed as a candidate tool to dampen HCC.

[Chemical Compositions and Source Apportionment of Road Dust in Yuncheng].

Samples of particulate sources in Yuncheng including road dust, salt lake dust, coal dust, soil dust, construction,cement dust and vehicle exhaust dust were collected. Elements, ions and carbon species in particulate sources samples were analyzed. Enrichment factors and potential ecological risk assessment were used to analyze the characteristics of road dust, and chemical mass balance model was applied to identify the source of road dust. The results showed that, compared with other cities, the proportions of Na(12.1970%) and SO42-(8.5971%) were relatively high while that of Si(9.1123%) was low in road dust in Yuncheng, and enrichment factors showed that the sources of Pb, Cu, Cr, V, As, Ni, Na and Zn in road dust were obviously influenced by human activities; the potential ecological risk of heavy metals in road dust was high, which was affected by anthropogenic sources such as industrial production, the combustion of fossil fuels and vehicle exhaust; the profiles of coal dust, vehicle exhaust dust, construction and cement dust were similar to those of other cities, the Na and SO42- concentrations in soil dust were relatively high, and the proportions of Na and SO42- in salt lake dust were 30.3% and 22.7% respectively; salt lake dust was the largest contributor (53%) to road dust, followed by the soil dust (21%), vehicle exhaust dust (8%), construction and cement dust (7%), and coal dust (5%).

[Characteristics of Chemical Components in PM2.5 from the Coal Dust of Power Plants].

The ashes under dust catcher of typical power plants in Yangquan was collected and the contents of elements, irons, EC (elemental carbon) and OC (organic carbon) were measured in PM2. The characteristics of its chemical composition was studied and the degree of similarity of coal dust's source profiles of PM2.5 between Yangquan and other cities were compared using the coefficient of divergence method. The result indicated that the main chemical components of PM2.5 from the coal dust were SO4²â»,Ca, NO3⁻, OC, EC, Al, Si, Na, Fe, Mg and Cl⁻, accounting for 57.22% of the total mass. The enrichment factor of Pb in PM2.5 of coal dust was the largest with a significant enrichment condition, reaching 10.66-15.91. The coefficient of divergence of source profiles of PM2.5 between blind coal and fault coal was 0.072, so it was believed that they must be similar. Compared with other cities, the chemical composition of coal dust in Yangquan had specificity, in particular, the content of Ca was obviously higher than those in other domestic cities.

[Chemical Compositions and Sources Apportionment of Re-suspended Dust in Jincheng].

In order to make effective plan to provide the scientific basis for prevention and control of re-suspended dust (RD), samples of particulate sources including RD and other pollution sources of Jincheng were collected. Elements, ions and carbon in particulate sources were analyzed. Enrichment factor, potential ecological risk assessment, and chemical mass balance model were used to analyze the chemical composition and the source of RD. The result indicated that the main components in RD of Jingeheng were Si, TC, Ca, OC, Al, Mg, Na, Fe, K and SO4(2-), contributing 61.14% of total mass of RD. The most abundant content of RD was crustal elements, and the ions were enriched in the fine particles. The mass fraction of OC in PM2. was higher, whereas the mass fraction of EC in PM10 was higher, indicating that secondary organic pollutants were mainly dominated in the fine particles. The dust PM2.5 and PM10 potential ecological risk indexes were extremely strong, and PM2.5 had higher ecological harm than PM10. Pb had the highest enrichment factor of 196.97 in PM2.5, which was followed by As, Cr, Ni, V, Zn and Cu, the enrichment factors of which were all greater than 10, indicating that they were apparently enriched and affected by human activities. Soil dust, construction dust, vehicle exhaust, and coal dust were the main sources of RD.

Characteristics of hopanoid hydrocarbons in ambient PM10 and motor vehicle emissions and coal ash in Taiyuan, China.

Hopanoid hydrocarbon content in ambient particulate matter (PM) of less than or equal to 10 µm aerodynamic diameter (PM10) was sampled at seven sites representative of different functional districts, and measured by gas chromatography-mass spectrometry. 17α(H),21ß(H)-hopane (C30αß) and 17α(H),21ß(H)-30-norhopane (C29αß) were dominant in all samples. Hopanes in motor vehicle emissions from various fuel-type engines (gasoline, diesel and natural gas) and coal ash were qualitatively measured, and the amount of C30αß was about two to three times greater than that of C29αß. Distinct seasonal variations (winter/summer differences) were observed at higher concentrations (45.54-108.29 ng/m(3)) of total hopanes in winter and lower (2.59-28.26 ng/m(3)) in summer. There were also clear spatial variations of hopanes in Taiyuan, with samples with greater hopane concentrations in downtown areas, but less in summer. The spatial distribution reversed in winter. Distributions and relative abundances of selected hopanes from PM10 and source emissions indicated that in summer, vehicle exhaust was the dominant fossil fuel combustion source (C30αß was >C29αß), and that the contribution of coal combustion was slightly greater at suburban sites. However, the contribution of coal combustion sources increased significantly at all sites in winter, especially in suburban areas, where C29αß exceeded C30αß. Hopanoid indexes revealed a classification of vehicle exhaust and coal combustion emissions in PM10. The results imply that during rapid urbanization, it is crucial to strengthen the construction of infrastructure such as central heating in new city districts and to increase the use of natural gas instead of residential coal burning.

[Characteristics of organic carbon and elemental carbon in PM2.5 in Shuozhou City].

PM2.5 samples were collected at four sampling sites in Shuozhou during the heating and non-heating periods. Organic carbon (OC) and elemental carbon (EC) in PM2.5 were analyzed by Elementar Analysensysteme GmbH vario EL cube and the concentration, spatial and temporal distribution characteristics and main sources of OC and EC were studied. The results were as following: average concentrations of OC and EC in PM2.5 during non-heating period were (14.3 ± 2.7) µg x m(-3) and (10.3 ± 3.1) µg x m(-3) while (23.3 ± 5.9) µg xm(-3) and (20.0 ± 5.7) µg x m(-3) during heating period. The concentrations of OC and EC at four sites during the heating period were higher than those during the non-heating period. The concentrations of OC and EC at SW site during heating were the highest which were 28.5 µg x m(-3) and 28.1 µg x m(-3) while the concentrations at PS sites during non-heating period were the highest, which were 17.7 µg x m(-3) and 14.1 µg x m(-3). The ratios between OC and EC during the heating and non-heating period were all below 2 and the correlation between OC and EC was not good with R2 of 0. 66 during heating period and 0.52 during non-heating period which indicated that sources of carbon aerosols were complex. Carbonaceous aerosol pollution should be reduced by controlling the primary emissions such as coal combustion, vehicle exhaust and biomass burning, and by paying attention to secondary pollution at the same time to improve the air quality in Shuozhou City. The concentrations of SOC during heating and non-heating period were (6.44 ± 2.77) µg x m(-3) and (4.11 ± 1.92) µg x m(-3).

Health risk assessment of toxic VOCs species for the coal fire well drillers.

In this study, the health risk of toxic volatile organic compounds (VOCs) species for well drillers, working at an exposure site around a well of underground coal fire site, was presented in a case of Shanxi province. The samples were collected by Teflon sampling bags and measured by gas chromatography-mass spectrometry (GC-MS). The results showed that isopropyl alcohol was the most abundant compound of VOCs, with the geometric mean concentrations of 1700.38 µg/m(3). The geometric mean concentrations of individual BTEX compounds obtained in all of the sampling campaign were 131.64, 10.15, 15.53, and 25.38 µg/m(3) for benzene, toluene, ethyl-benzene, and xylenes, respectively. Relative proportion of BTEX averaged as 8.5:0.7:1:1.6. High B/T ratio (13.0) and low T/E ratio (0.7) was observed in this study. For non-cancer risk in this study, the hazardous quotient (HQ) of 1,2-dibromoethane, 1,3-butadiene, and benzene was 17.91, 1.71, and 43.88, respectively, mean their non-cancer risk was at the level of definite concern. The HQ sum of 20 VOCs was 64.94, much higher than 1. The cancer risk values of benzene (7.01E-04), 1,2-dibromoethane (1.91E-04), carbon tetrachloride (1.55E-04), and 1,3-butadiene (1.09E-04) were greater than 10(-4), indicating that they were all definite risk. The total cancer risk of all VOCs species was 1.39E-03, almost 14 times more than the level of definite risk. The stochastic exposure assessment of all VOCs species total cancer risk using the Monte Carlo simulation analysis shows that 5 and 95 % cancer risks were predicted to be 7.60E-04 and 2.75E-03, respectively. The cancer risk for all VOCs species is unacceptable. The results of sensitivity analysis show that benzene, carbon tetrachloride, and 1,3-butadiene exposure account for more than 98 % contributions to the estimated risk for drillers, indicating that those VOCs species exposure has greater impact than other species on risk assessment. Both combined effects and independent effects of each VOCs species have to be considered.

The expression analysis of nanog in the developing rat myocardial tissues.

OBJECTIVES: To investigate the expression dynamic of nanog gene in the development of rat myocardial tissues. METHODS: SD rats were studied at 5 time points before and after birth. The techniques of immunohistochemistry, immunofluorescence, western blotting and RT-PCR were used to investigate the expression of nanog gene in the rat myocardial tissues at different embryonic (E) and postnatal (P) stages, and image analysis system was used for the quantitative analysis. RESULTS: The immunohistochemistry, immunofluorescence and western blotting analyses have shown that expression of nanog protein was highest in the rat myocardial tissues at E18, then it gradually declined at postnatal stages (P<0.05), and became nearly undetectable in most myocardial tissues at P30 with very few remaining nanog-positive cells. RT-PCR result indicated that the expression of nanog gene was strong at E18, but gradually decreased from E18 to P30. CONCLUSION: The mRNA transcription and protein translation of nanog gene in the rat heart gradually decreased with every consecutive growth stage. This indicates that nanog gene has potential regulatory functions in the differentiation of myocardial cells during rat development.