Fetal marfan syndrome: Prenatal ultrasound diagnosis with pathological confirmation of skeletal and aortic lesions

Sonography was performed during the second trimester in two pregnancies at risk for the Marfan syndrome. In one, the limbs were significantly longer than expected (p < 0·0025) and a diagnosis of the Marfan syndrome was established. Pathological examination of the fetus after pregnancy interruption showed typical foci of cystic medial necrosis in the ascending aorta.     

Pretreatment of sludge with microwaves for pathogen destruction and improved anaerobic digestion performance.

A new way of generating Class A sludge using microwaves was evaluated through a series of laboratory-scale experiments. Microwaves provide rapid and uniform heating throughout the material. Other benefits of microwave treatment include instant and accurate control and selective and concentrated heating on materials, such as sludge, that have a high dielectric loss factor. Sludge was irradiated with 2450-MHz microwaves, and fecal coliforms were counted. Fecal coliforms were not detected at 65 degrees C for primary sludge and anaerobic digester sludge and at 85 degrees C for waste activated sludge when sludge was irradiated with 2450-MHz microwaves. During the bench-scale anaerobic digester operation, the highest average log reduction of fecal coliforms was achieved by the anaerobic digester fed with microwave-pretreated sludge (> or = 2.66 log removal). The anaerobic digester fed with microwave-irradiated sludge was more efficient in inactivation of fecal coliforms than the other two digesters fed with raw sludge and externally heated sludge, respectively. It took more than three hydraulic retention times for a bench-scale mesophilic anaerobic digester to meet Class A sludge requirements after feeding microwave-irradiated sludge. Class A sludge can be produced consistently with a continuously fed mesophilic anaerobic digester if sludge is pretreated with microwaves to reach 65 degrees C.     

A direct passive method for measuring water and contaminant fluxes in porous media

This paper introduces a new direct method for measuring water and contaminant fluxes in porous media. The method uses a passive flux meter (PFM), which is essentially a self-contained permeable unit properly sized to fit tightly in a screened well or boring. The meter is designed to accommodate a mixed medium of hydrophobic and/or hydrophilic permeable sorbents, which retain dissolved organic/inorganic contaminants present in the groundwater flowing passively through the meter. The contaminant mass intercepted and retained on the sorbent is used to quantify cumulative contaminant mass flux. The sorptive matrix is also impregnated with known amounts of one or more water soluble 'resident tracers'. These tracers are displaced from the sorbent at rates proportional to the groundwater flux; hence, in the current meter design, the resident tracers are used to quantify cumulative groundwater flux. Theory is presented and quantitative tools are developed to interpret the water flux from tracers possessing linear and nonlinear elution profiles. The same theory is extended to derive functional relationships useful for quantifying cumulative contaminant mass flux. To validate theory and demonstrate the passive flux meter, results of multiple box-aquifer experiments are presented and discussed. From these experiments, it is seen that accurate water flux measurements are obtained when the tracer used in calculations resides in the meter at levels representing 20 to 70 percent of the initial condition. 2,4-Dimethyl-3-pentanol (DMP) is used as a surrogate groundwater contaminant in the box aquifer experiments. Cumulative DMP fluxes are measured within 5% of known fluxes. The accuracy of these estimates generally increases with the total volume of water intercepted.     

The effect of positive work reflection during leisure time on affective well‐being: Results from three diary studies

Previous research showed that psychological detachment from work during leisure time is beneficial and that reflecting on negative aspects of work is detrimental for employees' well‐being. However, little is known about the role of positive reflection about work during leisure time. In the present research, we examined the effects of positive work reflection on affective well‐being. Additionally, we tested the effectiveness of an intervention to increase positive work reflection and to improve well‐being with a randomized controlled field experiment. Findings from three diary studies showed that positive work reflection was related to an increase in affective well‐being with regard to both positive and negative moods. The results further indicated that the benefits of positive work reflection were incremental to that of psychological detachment and the absence of negative work reflection. Contrary to our expectation, no evidence was found for the effectiveness of the intervention. Theoretical implications of main findings as well as supplementary findings are further discussed. Copyright © 2015 John Wiley & Sons, Ltd.     

Microbial Degradation of PCBs in Contaminated Sediments

The extent of natural dechlorination varies widely in sediments and fails to reach its maximum potential. Recent laboratory and field studies have suggested that the potential for further dechlorination is low in the Hudson and St. Lawrence Rivers. Laboratory investigations have also indicated that polychlorinated biphenyl (PCB) dechlorination is directly coupled to the growth of dechlorinating microorganisms in that: (a) there was no growth of dechlorinating microorganisms below the threshold concentration, (b) the rate of chlorine removal per gram sediment was significantly correlated to the growth rate of the microorganisms, (c) the negative effect of lower moisture levels on dechlorination was correlated to the microorganism death rate, and (d) the extent of natural dechlorination in the St. Lawrence River appears to be related to the in-situ population size of dechlorinators. There also appear to be many dechlorinating populations, each with different requirements and competence. Therefore, the growth enhancement of these microorganisms is the key to promoting PCB dechlorination either in situ or ex situ. © 1999 John Wiley & Sons, Inc.     

Controlling various contaminants in wastewater effluent through membranes and engineered wetland

For effective wastewater reclamation and water recovery, the treatment of natural and effluent organic matters (NOM and EfOM), toxic anions, and micropollutants was considered in this work. Two different NOM (humic acid of the Suwannee River, and NOM of US and Youngsan River, Korea), and one EfOM from the Damyang wastewater treatment plant, Korea, were selected for investigating the removal efficiencies of tight nanofiltration (NF) and ultrafiltration (UF) membranes with different properties. Nitrate, bromate, and perchlorate were selected as target toxic anions due to their well known high toxicities. Tri-(2-chloroethyl)-phosphate (TCEP), oxybenzone, and caffeine, due to their different K _ow and pK _a values, were selected as target micropollutants. As expected, the NF membranes provided high removal efficiencies in terms of all the tested contaminants, and the UF membrane provided fairly high removal efficiencies for anions (except for nitrate) and the relatively hydrophobic micropollutant, oxybenzon. Through the wetlands, nitrate was successfully removed. Therefore, a fair process of combining membranes with an engineered wetland could be proposed for sustainable wastewater reclamation and optimum control of contaminats.     

Effects of heavy rainfall on the composition of airborne bacterial communities

Wet deposition scavenges particles and particle-associated bacteria from the air column, but the impact of raindrops on various surfaces on Earth causes emission of surface-associated bacteria into the air column. Thus, after rainfall, these two mechanisms are expected to cause changes in airborne bacterial community composition (BCC). In this study, aerosol samples were collected at a suburban site in Seoul, Korea before and after three heavy rainfall events in April, May, and July 2011. BCC was investigated by pyrosequencing the 16S rRNA gene in aerosol samples. Interestingly, the relative abundance of non-spore forming Actinobacteria operational taxonomic units (OTUs) was always higher in post-rain aerosol samples. In particular, the absolute and relative abundances of airborne Propionibacteriaceae always increased after rainfall, whereas those of airborne Firmicutes, including Carnobacteriaceae and Clostridiales, consistently decreased. Marine bacterial sequences, which were temporally important in aerosol samples, also decreased after rainfall events. Further, increases in pathogen-like sequences were often observed in post-rain air samples. Rainfall events seemed to affect airborne BCCs by the combined action of the two mechanisms, with potentially adverse effects on human and plant health.

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Review of total suspended particles (TSP) and PM<Subscript>2.5</Subscript> concentration variations in Asia during the years of 1998–2015

In Asian countries such as China, Malaysia, Pakistan, India, Taiwan, Korea, Japan and Hong Kong, ambient air total suspended particulates and PM_2.5 concentration data were collected and discussed during the years of 1998–2015 in this study. The aim of the present study was to (1) investigate and collect ambient air total suspended particulates (TSP) and PM_2.5 concentrations for Asian countries during the past two decades. (2) Discuss, analyze and compare those particulates (TSP and PM_2.5) annual concentration distribution trends among those Asian countries during the past two decades. (3) Test the mean concentration differences in TSP and PM_2.5 among the Asian countries during the past decades. The results indicated that the mean TSP concentration order was shown as China > Malaysia > Pakistan > India > Taiwan > Korea > Japan. In addition, the mean PM_2.5 concentration order was shown as Vietnam > India > China > Hong Kong > Mongolia > Korea > Taiwan > Japan and the average percentages of PM_2.5 concentrations for Taiwan, China, Japan, Korea, Hong Kong, Mongolia and Other (India and Vietnam) were 8, 21, 6, 8, 14, 13 and 30%, respectively, during the past two decades. Moreover, t test results revealed that there were significant mean TSP and PM_2.5 concentration differences for either China or India to any of the countries such as Taiwan, Korea and Japan in Asia during the past two decades for this study. Noteworthy, China and India are both occupied more than 60% of the TSP and PM_2.5 particulates concentrations out of all the Asia countries. As for Taiwan, the average PM_2.5 concentration displayed increasing trend in the years of 1998–1999. However, it showed decreasing trend in the years of 2000–2010. As for Korea, the average PM_2.5 concentrations showed decreasing trend during the years of 2001–2013. Finally, the average PM_2.5 concentrations for Mongolia displayed increasing trend in the years of 2004–2013.     

Identification of the sources of PM10 in a subway tunnel using positive matrix factorization

The level of particulate matter of less than 10 μm diameter (PM₁₀) at subway platforms can be significantly reduced by installing a platform screen-door system. However, both workers and passengers might be exposed to higher PM₁₀ levels while the cars are within the tunnel because it is a more confined environment. This study determined the PM₁₀ levels in a subway tunnel, and identified the sources of PM₁₀ using elemental analysis and receptor modeling. Forty-four PM₁₀ samples were collected in the tunnel between the Gireum and Mia stations on Line 4 in metropolitan Seoul and analyzed using inductively coupled plasma–atomic emission spectrometry and ion chromatography. The major PM₁₀ sources were identified using positive matrix factorization (PMF). The average PM₁₀ concentration in the tunnels was 200.8 ± 22.0 μg/m³. Elemental analysis indicated that the PM₁₀ consisted of 40.4% inorganic species, 9.1% anions, 4.9% cations, and 45.6% other materials. Iron was the most abundant element, with an average concentration of 72.5 ± 10.4 μg/m³. The PM₁₀ sources characterized by PMF included rail, wheel, and brake wear (59.6%), soil combustion (17.0%), secondary aerosols (10.0%), electric cable wear (8.1%), and soil and road dust (5.4%). Internal sources comprising rail, wheel, brake, and electric cable wear made the greatest contribution to the PM₁₀ (67.7%) in tunnel air.

ImplicationsWith installation of a platform screen door, PM₁₀ levels in subway tunnels were higher than those on platforms. Tunnel PM₁₀ levels exceeded 150 μg/m³ of the Korean standard for subway platform. Elemental analysis of PM₁₀ in a tunnel showed that Fe was the most abundant element. Five PM₁₀ sources in tunnel were identified by positive matrix factorization. Railroad-related sources contributed 68% of PM₁₀ in the subway tunnel.