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The atmospheric mixing state and emission rates play decisive roles in public exposure to urban air pollution. This study utilizes atmospheric radon measurements taken with the SM200 “stability monitor,” which reflect changes in the atmospheric mixing state, to evaluate and forecast air quality. Using six months (March–August 2016) of atmospheric radon measurements in Jinhua, China, we classify the nocturnal atmospheric stability conditions into four distinct categories, “well-mixed”, “weakly stable”, “moderately stable”, and “most stable”, by applying a modified radon-based stability technique. We calculate the atmospheric self-cleaning ability index (ASI) and evaluate it with the four-category stability scheme, and the results confirm that the atmospheric radon measurements reliably represent the atmospheric mixing state. Analyzing PM2.5, PM10, SO2, NO2, CO, and O3 measurements from three nearby stations during the campaign, we find that the pollutant concentrations and air quality index (AQI) values assigned using the aforementioned stability scheme are consistent with the defined atmospheric mixing states. We subsequently demonstrate that the modified radon-based stability method is suitable for targeting the most unfavorable air quality conditions and determining where the emissions originated. Finally, we propose a simple ASI-based model for predicting regional severe air pollution.

A recently-developed radon-based technique is modified to quantify the seasonal influences of atmospheric stability on urban emissions in Lanzhou, China, based on 11 months of observations at three sites with contrasting pollution characteristics. Near-surface concentrations of primary (CO, SO 2 , NO x ) and secondary (O 3 ) gas phase pollutants responded to changing atmospheric stability in markedly different ways in winter and summer, primarily because monsoonal fetch changes strongly influenced the distance between measurement sites and their nearest upwind pollutant sources, but also due to mean diurnal changes in mixing depth. Typically, morning peak primary pollution concentrations increased by a factor of 2–5 from the most well-mixed to stable conditions, whereas nocturnal ozone concentrations reduced with increasing stability due to surface loss processes and the progressively reduced coupling between the nocturnal boundary layer and overlying free atmosphere. The majority of pollution exceedance events (cf. China National Air Quality Standard guideline values) occurred in winter, when all measurement stations were downwind of the city's main pollution sources, and were directly attributed to morning periods and stable atmospheric conditions. In the sheltered valley region of Lanzhou, extremes of winter nocturnal stability states represented a change in mean nocturnal wind speed of only 0.25 m s −1 (from 0.6 to 0.85 m s −1 ). Daily-integrated PM 10 concentrations increased by a factor of 2 in winter from the most well-mixed to stable conditions, and were usually above guideline values at the industrial and residential sites for all atmospheric stability conditions. In summer, however, daily mean PM 10 exceedances usually only occurred at the industrial site, under stable conditions. Finally, a simple model – based on mean radon concentrations between 1900 and 0400 h – is proposed to predict haze conditions in the city prior to commencement of the peak morning commuting time.

Within the Sino-Italian environmental protection cooperation framework established in 2002, a comprehensive air quality monitoring network has been developed in urban Suzhou, a medium-sized Chinese city, in compliance with European standards (Directive 96/62/EC). This paper is among the first attempts to present a systematic and scientific analysis of benzene, toluene, and xylenes (BTX) pollution in China. It presents our analysis of BTX space-related and time-related measurement results. Background BTX concentrations were investigated by passive sampler Analyst(R) in 2003. We depicted the spatial distribution of average BTX concentrations collected from three 15-day campaigns on isoconcentration maps. This is the first time such detailed BTX concentration maps have been developed in China in a city scale. Continuous measurement of BTX by automatic gas chromatography was carried out at two fixed monitoring stations, one in an urban residential zone and one in a heavy traffic zone, from April to December 2005. The results show similar seasonal trends at both sites, the similarities reaching their greatest level in December and their lowest level in August. The average daily profile of BTX shows greater fluctuation in spring and winter with clear morning and evening peaks. Daily average benzene, toluene, and m,p-xylenes concentrations for the study period were 2.64, 11.52, and 3.52 microg m(-3), respectively. The benzene/toluene ratio we found was lower in Suzhou than those published in studies of other worldwide cities, which indicates serious levels of toluene pollution from local stationary sources. The similarities in seasonal trend and spatial distribution in these manual and automatic measurement results were compared with each other, though the concentration values differed.

Purpose: Classification based on a combination of molecular and pathologic predictors had never been done using hierarchical cluster analysis. For this purpose, we identified prognostic classification based on molecular predictors, pathologic and molecular predictors, and compared their respective prognostic efficacy together with that of tumor-node-metastasis (TNM) stage. Moreover, we investigated the prognostic significance of molecular classification in different TNM stage. Experimental Design: Six pathologic predictors (p) and 13 immunohistochemical predictors (m) were investigated in 221 colorectal carcinomas. Unsupervised hierarchical clustering analysis was done to group the data. Survival analysis was done by Kaplan-Meier method and log-rank test, and by multivariate COX proportional hazard model. Results: Six pathologic predictors and four molecular predictors were of significant prognostic value (P ≤ 0.05). One molecular predictor showed a trend toward significance (P = 0.085). Hierarchical clustering analysis was done based on different combinations (5p, 13m, 5m, 5p13m, and 5p5m), and distinct groups were produced except 5p (the TNM stage was excluded). Groups identified by 5m (P = 0.053) and 5p5m (P = 0.000) showed significant differences in prognosis. Groups identified by 5p5m and TNM stage were confirmed as the independent prognostic factors in a multivariate COX proportional hazard model. Moreover, groups identified by 5m could predict different prognoses in patients with stage II disease. Conclusions: Classification based on pathologic and immunohistochemical predictors is superior to that based only on molecular predictors on prognosis. Classification based on 5m could identify additional different prognoses in patients with stage II disease.

Commercially-available “stability monitors” based on in situ atmospheric radon progeny measurements remain underutilised as a tool for urban pollution studies, due in part to difficulties experienced in relating their standard output directly to the atmospheric mixing state in a consistent manner. The main confounding factor has been a lack of attention to the fact that the observed near-surface atmospheric radon concentration includes large synoptic and fetch-related components in addition to the local stability influence. Here, a technique recently developed for stability classification using a research-quality dual-flow-loop two-filter radon detector is adapted for use with a commercially-available radon-based stability monitor. Performance of the classification scheme is then tested in Lanzhou, China, a topographically-complex region renowned for low mean annual wind speeds (0.8 m s −1 ) and winter stagnation episodes. Based on an 11-month composite, a factor of seven difference is estimated between peak NO x concentrations in the city's industrial region and a rural background location under stable conditions. The radon-based scheme is evaluated against the Pasquil-Gifford “radiation” (PGR) scheme, and assigns pollutant concentrations more consistently between defined atmospheric stability states than the PGR scheme. Furthermore, the PGR scheme consistently underestimates all peak pollutant concentrations under stable conditions compared with the radon-based scheme, in some cases (e.g. CO in the industrial region) by 25%.

Vertical distribution of traffic-related pollutants inside an open street-canyon were observed in Suzhou, P.R. China, in 2005. The aim was to explore transfer and diffusion characteristics of vehicular exhaust emissions, as well as monitoring constraints associated with street canyons, courtyards and enclosed spaces. Vertical wind speed was found to strongly affect the fluctuation of all the pollutants. Daily average concentrations of NO x , NO 2 and NO, as well as NO 2 /NO x ratio, were found to vary significantly alongside the vertical, proportionate to different average daily trends. Oxidation processes and photochemical activity are discussed to explain these phenomena. Daily CO trends were found to track closely with both NO x and Benzene, while the corresponding ratios were different relative to other published works. Different emission factors and driving conditions, as well as other emission sources types (especially for Benzene) are used to explain this point.

The particle formation and growth events observed at a semirural background site in Denmark were analyzed based on particle number size distribution data collected during the period from February 2005 to December 2010. The new particle formation (NPF) events have been classified visually in detail according to 3D daily plots in combination with an automatic routine. A clear seasonal variation was found in the way that events occurred more frequently during the warm season from May to September and especially in June. The mean values of the apparent 6 nm particle formation rates, the growth rate and the condensation sink were about 0.36 cm−3 s−1, 2.6 nm h−1, 4.3 × 10−3 s−1, respectively. A positive relationship of oxidation capacity (OX = O3 + NO2) of the atmosphere and the appearance of NPF events was found indicating that the oxidation of the atmosphere was linked to the formation of new particles. An analysis of a 3-day backward trajectories revealed that NW air masses from the North Sea were giving the highest probability of NPF events, namely between 20 and 40 %.

Colorectal carcinoma with a micropapillary component (MP) is an exceptionally aggressive variant, but has never been investigated in terms of survival analysis. Thirty colorectal carcinomas with a MP were identified from a series of 221 colorectal carcinomas. Carcinomas with and without a MP were compared in terms of histologic and immunohistochemical markers. Colorectal carcinoma with a MP seemed to have a lower differentiation status, increased tumor budding, more frequent lymphovascular and perineural invasion, more frequent lymph node metastasis, higher tumor node metastasis (TNM) stage, and less nuclear beta-catenin staining (P

Passive sampling technique was used to preliminary assess the spatial and temporal distribution of air pollution in Suzhou (P.R. China) in 2003, with the aim to determine the representativeness of zones where to monitor air quality. 100 sites were selected to measure 15-days average concentrations of SO2, NOx, NO2, O-3, NH3, Benzene, Toluene and Xylene in winter and summer. The distribution trend of NO and NO2, as well as the ratio of NO2/NOx was used to identify the heavy traffic polluted zones and design a network of monitoring stations (macrositing). NO2/NOx ratios varied throughout the two selected seasons and from site to site clearly demonstrating the different extent and completeness of NO -> NO2 oxidation processes in time and space. The exceedance frequencies of pollutants was used to design the type of monitoring equipment to be installed at each station (micrositing). An air quality monitoring network composed by 9 monitoring stations has been finally established in 2004 according to the result of this Survey and is now currently running.

Nitrogen oxides (NO 2 and NO x ), sulphur dioxide (SO 2 ), and benzene, toluene, xylene (BTX) in ambient air were preliminarily assessed, by diffusive sampling technique, in 2003 through three measurement campaigns at 100 locations in the Chinese city of Suzhou. Statistical analysis of space series so-generated was performed to infer source contributions and frequency distributions (FD). It was found that nitrogen oxides, benzene and xylene were mostly emitted from motor vehicles; in contrast, industrial sources were a major contributor to sulfur and toluene pollution. Normal FD (NFD) described significantly SO 2 in summer and NO 2 and NO x in autumn (95% confidence interval); on the contrary, BTX presented a most peculiar FD rather different to the NFD. Lognormal distribution was often unacceptable. Predominant factors influencing FDs and its normality were found to be associated to those elements conditioning air pollutant diffusion: meteorology (wind speed and direction), relevant emission sources (especially for toluene), emission seasonality (mainly for SO 2 and NO x ), and photochemistry (mainly for NO 2 and xylene).

A novel H7N9 influenza A virus has been discovered as the causative identity of the emerging acute respiratory infection cases in Shanghai, China. This virus has also been identified in cases of infection in the neighboring area Hangzhou City in Zhejiang Province. In this study, epidemiologic, clinical, and virological data from three patients in Hangzhou who were confirmed to be infected by the novel H7N9 influenza A virus were collected and analyzed. Human respiratory specimens and chicken feces from a contacted free market were tested for influenza virus by real-time reverse transcription PCR (RT-PCR) and sequencing. The clinical features of the three cases were similar featured with high fever and severe respiratory symptoms; however, only one of the patients died. A certain degree of diversity was observed among the three Hangzhou viruses sequenced from human samples compared with other reported H7N9 influenza A viruses. The sequences of the novel avian-origin H7N9 influenza viruses from Hangzhou City contained important amino acid substitutions related to human adaptation. One of the Hangzhou viruses had gained a novel amino acid substitution (Q226I) in the receptor binding region of hemagglutinin. More importantly, the virus sequenced from the chicken feces had a 627E substitution in the PB2 protein instead of the mammalian-adapted 627K substitution that was found in the PB2 proteins from the Hangzhou viruses from the three patients. Therefore, the newly-emerging H7N9 virus might be under adaptation pressure that will help it “jump” from avian to human hosts. The significance of these substitutions needs further exploration, with both laboratory experiments and extensive field surveillance.

Background A total of 453 laboratory-confirmed cases infected with avian influenza A (H7N9) virus (including 175 deaths) have been reported till October 2,2014, of which 30.68% (139/453) of the cases were identified from Zhejiang Province. We describe the largest reported cluster of virologically confirmed H7N9 cases, comprised by a fatal Index case and two mild secondary cases. Methods A retrospective investigation was conducted in January of 2014. Three confirmed cases, their close contacts, and relevant environments samples were tested by real-time reverse transcriptase-polymerase chain reaction (RT-PCR), viral culture, and sequencing. Serum samples were tested by haemagglutination inhibition (HI) assay. Results The Index case, a 49-year-old farmer with type II diabetes, who lived with his daughter (Case 2, aged 24) and wife (Case 3, aged 43) and his son-in-law (H7N9 negative). The Index case and Case 3 worked daily in a live bird market. Onset of illness in Index case occurred in January 13, 2014 and subsequently, he died of multi-organ failure on January 20. Case 2 presented with mild symptoms on January 20 following frequent unprotected bed-side care of the Index case between January 14 to 19, and exposed to live bird market on January 17. Case 3 became unwell on January 23 after providing bedside care to the Index case on January 17 to 18, and following the contact with Case 2 during January 21 to 22 at the funeral of the Index case. The two secondary cases were discharged on February 2 and 5 separately after early treatment with antiviral medication. Four virus strains were isolated and genome analyses showed 99.6 ~100% genetic homology, with two amino mutations (V192I in NS and V280A in NP). 42% (11/26) of environmental samples collected in January were H7N9 positive. Twenty-five close contacts remained well and were negative for H7N9 infection by RT-PCR and HI assay. Conclusions In the present study, the Index case was infected from a live bird market while the two secondary cases were infected by the Index case during unprotected exposure. This family cluster is, therefore, compatible with non-sustained person-to-person transmission of avian influenza A/H7N9. Electronic supplementary material The online version of this article (doi:10.1186/s12879-014-0698-6) contains supplementary material, which is available to authorized users.