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Water treatment plants (WTPs) that intake raw water from the Paldang Dam of the Han River have generally adopted ozone + granular activated carbon (GAC) processes for the effective removal of taste and odor substances. In recent years, the concentration and duration of the substances causing taste and odor in Paldang Lake have gradually increased. Therefore, it is necessary to review the appropriateness of the advanced water treatment processes introduced in the WTPs located in the Han River. This study attempted to compare and review two processes for geosmin removal, one using a pre-ozone GAC filter-adsorber (pre-ozone + F/A) at the B WTP and the other using a post-ozone GAC adsorber (post-ozone + GAC) at the G WTP. The results of the investigation for geosmin and 2-MIB concentrations upstream of the Paldang Dam over the past 5 years showed that 2-MIB exceeded the standard concentration for less than 5 d per year and geosmin was the main cause of taste and odor. At the B WTP in the winter of 2011, the total geosmin concentration in the treated water exceeded 20 ng/L twice. Additionally, the average total geosmin concentration of the treated water after the application of the F/A was 7.81 ng/L. On the other hand, in the case of the G WTP, the total geosmin concentration after post-ozone and GAC treatment was 0.45 ng/L. In the summer of 2012, the fraction of particulate geosmin (66.9%-82.3%) was higher than that of dissolved geosmin (17.7%-33.1%) in the raw water of the two WTPs. During this period, the average removal rates of total geosmin in the final treated water of the G WTP were 0.7% higher than that of the B WTP. Therefore, ozone injection into filtered water after removing particulate geosmin and organic substances through the standard treatment process (coagulation, sedimentation, and filtration) is thought to be effective for removal to lower the concentration of dissolved organic matter and dissolved geosmin. In conclusion, the treatment efficiency was confirmed to vary according to the stage at which the process was used, even when the same ozone + activated carbon adsorption process was used. In addition, the 'post-ozone + GAC' method is considered advantageous when introducing advanced WTPs in the Han River. [ABSTRACT FROM AUTHOR]

Purpose/objective(s): To monitor intrafraction motion during spine stereotactic radiosurgery (SRS) treatment delivery with readily available device, we implemented triggered kV imaging using the on-board imager of the medical linear accelerator advanced imaging package.Materials/methods: Triggered kV imaging technique was clinically implemented and applied to 32 spine SBS patients (75 fx, 20 T-spine tumors, 12 L-spine tumors) during VMAT delivery. Currently available trigger options in the medical linear accelerator software package are MU, gantry angle, time, and respiratory gating. Time trigger was selected to acquire kV images every 15 seconds, in an effort to balance temporal resolution with reasonable time for image evaluation. Upon each image acquisition, a 2D projection of the 3D image-guided radiotherapy (IGRT) structures was automatically calculated and updated at arbitrary angles as a qualitative visual guide for patient alignment during treatment delivery. For IGRT structures, patient anatomy (vertebra and spinous process) and orthopedic hardware if present were contoured, with a 1 mm expansion. As the technique depends on visual inspection, decisions could vary depending on interobserver variability. Therefore, a survey of 10 trained physicists (4) and physicians (6) was conducted to evaluate efficiency and accuracy of clinical decision with kV images collected using an anthropomorphic phantom with different CT slice thicknesses and shifts introduced. The survey consisted of 192 sample images. The participants were asked to determine if a shift requiring intervention was observed. Average time per decision was recorded.Results: The robustness of our current patient immobilization system was validated in our clinical implementation. Based on visual inspection of projected IGRT contours on planar kV images, appreciable movement was detected in only one fraction (1.3%). However, in this instance, motion was well beyond PTV/PRV margins (2.4 mm) and treatment was stopped to take a CBCT and correct the displacement, which otherwise would have not been detected. From the survey, the average time spent per decision was 7.5 seconds. In all shift directions, detectability was proportional to the shift size and superior detectability was observed with contours drawn using CT images with 1 mm slice thickness. Shifts smaller than 1 mm are less noticeable (12.6%) compared to 2 mm shifts (42.6%). Participant detection capability was dependent on the level of training.Conclusion: This approach provides an effective, non-invasive intrafraction motion monitoring solution, using the built in triggered-imaging technique of the medical linear accelerator. One of the benefits this technique offers is that it can serve as a quality assurance approach to verify adequacy of a patient immobilization system. An important limitation is that the monitoring result is qualitative and depends on observer visual detection capability. Enhanced precision and utility could be achieved if an automated quantitative evaluation feature is implemented.Author Disclosure: J. Koo: None. L.Nardella: None. M.Degnan: None. J.Andreozzi: None. H.M. Yu: Honoraria; UpToDate. Speaker's Bureau; BrainLab. Advisory Board; Novocure, AbbVie. J.A.Penagaricano: None. P.A. Johnstone: None. D.E. Oliver: None. K.A. Ahmed: Research Grant; Bristol-Myers Squibb, Genentech. S.Rosenburg: Consulting; Novocure. E.J.Wuthrick: Research Grant; BMS. Honoraria; Regeneron/Sanofi, Varian. Consultant; Regeneron/Sanofi, Varian. R. Diaz: Honoraria; Zeiss; Global Health Outreach. V.Feygelman: None. E.G. Moros: Research Grant; Varian Medical Systems. Promote research in the AAPM; American Association of Physicists in Medicine. Promoting research in the AAPM; American Association of Physicists in Medicine. G.Redler: None. [ABSTRACT FROM AUTHOR]

In Korea, the percentage of pipelines more than 21 years old is reaching 22.7% and the demand for renewal will increase rapidly. This study is intended to determine the validation of renewal through Contingent Valuation Method (CVM) and through the estimation of pipeline burst in the future. Considering calculated benefit and cost, analysis period and social discount rate, the benefit/cost ratio is calculated and the result of B/C value is 1.004. Since the ratio of benefit/cost is bigger than 1.0, pipeline renewal with rehabilitation and double-piping is financially validated in this study. [ABSTRACT FROM AUTHOR]

Abstract: Chlorine compounds are widely used in water distribution systems to prevent waterborne diseases. Maintaining a sustainable level of residual chlorine in domestic tap water is important to ensure the quality of drinking water. In this study, we designed and fabricated a pilot-scale water distribution system to explore the relationship between the hydraulic conditions and the temporal variation in chlorine concentration. Various hydraulic conditions were introduced during operation, and temporal variations in chlorine concentration were recorded. The existing chlorine models that are used for water distribution systems can be categorized into three distinct groups. A genetic algorithm was used to calibrate the parameters of the various models and hydraulics. Regression analysis under turbulent conditions indicated that the fitted parameters from several chlorine models significantly were correlated with Reynolds numbers. The parameter space of several chlorine decay models was configured in conjunction with the hydraulic condition, and parameters were modeled under various flow conditions. Validation of the chlorine decay models under turbulent flow condition (Reynolds numbers of 15,000-40,000) showed good agreement (R2 > 0.8) with the experimental observations obtained from the pilot plant system. [Copyright &y& Elsevier]

Abstract: The phase change material (PCM) could be added to the wallboard to increase the thermal mass to decrease in indoor temperature fluctuation and improve thermal comfort. In this study, experimentally validated simulation was performed to investigate the effects of various parameters of PCM including the nominal average phase change temperature, its range, the convective heat transfer coefficients and the wallboard thickness on the thermal storage performance of the wallboard such as the thermal energy storage and the time shift. It was found that the average phase change temperature should be close to the average room temperature to maximize the thermal heat storage in the wallboards. The phase change temperature should be narrow to maximize the thermal heat storage in the PCM wallboards. The thermal heat storage increased with the convective heat transfer coefficient, and the optimal average phase change temperature to maximize the storage shifted a bit to a higher temperature with it. The time shift was found to decrease with the convective heat transfer coefficient and the phase change temperature range. [Copyright &y& Elsevier]

Background: The objective of the study was to evaluate the implications of androgen receptor (AR) in breast cancers.Patients and methods: We investigated immunohistochemical AR expression from the tissue microarrays of 931 patients between 1999 and 2005, and analyzed demographics and outcomes using uni-/multivariate analyses. Tumors with ≥10% nuclear-stained cells were considered positive for AR.Results: AR was expressed in 58.1% of patients. AR was significantly related to older age at diagnosis, smaller size, well-differentiated tumors, higher positivity of hormone receptors, non-triple-negative breast cancers (non-TNBCs), and lower proliferative index. In estrogen receptor (ER)-negative tumors, AR was distinctively associated with human epidermal growth factor receptor type 2 (HER2) overexpression. With a mean follow-up of 72.7 months, AR was positively related to survival in ER-positive but not in ER-negative tumors. In Cox’s models, AR was an independent prognostic factor for disease-free survival in ER-positive cancers. Interestingly, molecular apocrine tumors (ER negative and AR positive) with HER2 positive status showed trends of poorer outcome, but AR had no impact on survival in patients with TNBC.Conclusions: AR is significantly associated with favorable features in breast cancers and related to better outcomes in ER-positive not in ER-negative tumors. These results suggest that AR could be an additional marker for endocrine responsiveness in ER-positive cancers and a candidate for therapeutic targeting of ER-negative tumors. [ABSTRACT FROM AUTHOR]

Background: To investigate the clinicopathological significance of androgen receptor (AR) expression in primary breast cancers. [ABSTRACT FROM PUBLISHER]

Segmentation of head and neck (HN) organs at risk (OARs) is a laborious process. Here we introduce and validate a newly developed deep-learning-based auto-segmentation program and compare with a commercially available system, and the same system trained on internal data. A total of 864 previously treated HN cancer patients were available to train and evaluate a prototype deep learning-based normal tissue 3D auto-segmentation algorithm. The algorithm is based on a fully convolutional network with U-Net and V-net features combined as the backbone of the network. A Dice loss function with the Adam optimizer was used in training the models with between 150-500 patients used per model. The OARs were delineated by a single experienced physician (gold data). A subset of 75 cases was withheld from training and used for validation. On those, we generated new OAR sets with three different deep-learning models and compared to the gold data: A) the prototype model trained with gold data, B) a commercial software package trained with the gold data (n=213), and C) the same commercial software with the model trained at another institution (n=589). The agreement between the gold data and auto-segmented structures was evaluated with Dice similarity coefficient (DSC) and voxel-penalty metric that penalizes each missing or extra pixel as a function of distance with forgiveness threshold distance. An ANOVA test with post hoc pair-wise analysis was performed to assess the differences in those metrics. The auto-segmented contours were also qualitatively evaluated by the physician on a scale of 0-5. The average DSC and voxel penalty metric scores for algorithms A, B, and C across all OARs in the 75 evaluation cases were 0.80/77.68, 0.74/62.75, and 0.66/45.26, respectively. The difference in mean DSC scores was statistically significant (p<0.05) for all 11 OARs where the data for all three algorithms were available. The A/B difference was significant in 6 OARs. Algorithm A scored the highest DSC and voxel penalty metric score in all OARs except for the pharyngeal constrictors. All OARs except for the pharyngeal constrictors showed DSC≥0.7 with algorithm A. For three structures the mean DSC was significantly different between the same algorithm trained at different institutions(B/C). From the qualitative evaluation by a blinded expert, 51 structures (20.2%) of model A were clinically acceptable without edits. The percentages of 'clinically useful' scores were largest in model A (95.2%) followed by model B (88.0%) and C (80.6%). The prototype algorithm had improved performance compared to a commercial algorithm, even when trained on data from the same institution. Auto segmentation results can differ significantly when the same algorithm is trained on data from different institutions. [ABSTRACT FROM AUTHOR]

Abstract: As the pattern size scales down and the wafer size increases, the particle defects should be controlled more strictly in the modern microelectronics fabrication. Single wafer cleaning processes are introduced in the industry due to higher particle removal efficiency and lower particle reattachment possibility. In this study, the origins of watermark defects in single wafer cleaning system were identified, and the ways to avoid the problems were suggested through a model based numerical simulation. The watermark defects observed in the single wafer cleaning systems were found to originate from the failure of controlling water and iso-propyl alcohol (IPA) relative humidities in the surrounding gas. Increasing the IPA relative humidity in the surrounding gas during the drying phase could improve watermark defects and increase product yields. [Copyright &y& Elsevier]

Abstract: Participation in carbon (C) markets could provide farmers in developing countries incentives for improving soil fertility. However carbon traders need assurances that contract levels of C are being achieved. Thus, methods are needed to monitor and verify soil C changes over time and space to determine whether target levels of C storage are being met. Because direct measurement over the large areas needed to sequester contract amounts of C in soil is not practical, other approaches are necessary. An integrated approach is described in which an Ensemble Kalman Filter (EnKF) is used to assimilate in situ soil carbon measurements into a stochastic soil C model to estimate soil C changes over time and space. The approach takes into account errors in in situ measurements and uncertainties in the model to estimate mean and variance of soil C for each land unit within a larger land area. The approach requires initial estimates of soil C over space along with uncertainties in these estimates. Model predictions are made to estimate soil C for the next year, in situ soil C measurements update these predictions using maximum likelihood methods, and the spatial pattern of soil C mean, variance, and covariance thus evolve over time. This approach can also be used to provide yearly estimates of the changes in soil C over multiple fields, the variance in those estimates, and aggregate soil carbon mean and variance values each year. In this paper, the use of the EnKF is shown for an area in Ghana with 12 fields, comparing numbers of fields sampled each year and ways of selecting which fields to sample each year. The model predicts soil C changes over time using first order decomposition of existing soil C and addition of C from plant residues. The lowest intensity sampling method (sampling only 1/4 of the fields per year) resulted in the highest level of uncertainty in aggregate soil C estimate. Rotating sample fields each year improved the performance of the EnKF. These results demonstrated a quantifiable tradeoff between field sampling intensity and uncertainty in aggregate soil C estimates. The framework could be modified to use more complex biophysical models and to assimilate remote sensing data. [Copyright &y& Elsevier]

Abstract: In response to the ever increasing demand for smaller and lighter high-performance cooling devices, steady laminar liquid nanofluid flow in microchannels is simulated and analyzed. Considering two types of nanofluids, i.e., copper-oxide nanospheres at low volume concentrations in water or ethylene glycol, the conjugated heat transfer problem for microheat-sinks has been numerically solved. Employing new models for the effective thermal conductivity and dynamic viscosity of nanofluids, the impact of nanoparticle concentrations in these two mixture flows on the microchannel pressure gradients, temperature profiles and Nusselt numbers are computed, in light of aspect ratio, viscous dissipation, and enhanced temperature effects. Based on these results, the following can be recommended for microheat-sink performance improvements: Use of large high-Prandtl number carrier fluids, nanoparticles at high volume concentrations of about 4% with elevated thermal conductivities and dielectric constants very close to that of the carrier fluid, microchannels with high aspect ratios, and treated channel walls to avoid nanoparticle accumulation. [Copyright &y& Elsevier]

Abstract: Modern heat rejection systems, such as micro-heat sinks, are attractive because of their potential for high performance at small size and low weight. However, the impact of microscale effects on heat transfer have to be considered and quantitatively analyzed in order to gain physical insight and accurate Nusselt number data. The relative surface roughness (SR) was selected as a key microscale parameter, represented by a porous medium layer (PML) model. Assuming steady laminar fully developed liquid flow in microchannels and microtubes, the SR effects in terms of PML thermal conductivity ratio and Darcy number on the dimemsionless temperature profile and Nusselt number were analyzed. In summary, the PML characteristics, especially the SR-number and conductivity ratio k m/k f, greatly affect the heat transfer performance where the Nusselt number can be either higher or lower than the conventional value. The PML influence is less pronounced in microtubes than in parallel-plate microchannels. [Copyright &y& Elsevier]

The effects of viscous dissipation on the temperature field and ultimately on the friction factor have been investigated using dimensional analysis and experimentally validated computer simulations. Three common working fluids, i.e., water, methanol and iso-propanol, in different conduit geometries were considered. It turns out that for microconduits, viscous dissipation is a strong function of the channel aspect ratio, Reynolds number, Eckert number, Prandtl number and conduit hydraulic diameter. Thus, ignoring viscous dissipation could affect accurate flow simulations and measurements in microconduits. [Copyright &y& Elsevier]

The overall aim of this research was to develop egg freshness prediction models in terms of selected quality indices. Six experiments (4 constant temperatures and 2 variable temperatures) were carried out on hen eggs for a total period of 10, 21, 26, 13, and 105 d at storage temperatures of 30, 20, 20 to 10, 30 to 10, and 5 and 10°C, to observe trends in the relative weight loss (RWL), Haugh unit (HU), yolk index (YI), albumin index (AI), yolk pH, and albumin pH. The results showed that there was an increasing trend in the RWL and a decreasing trend in the YI, AI, and HU for all temperature conditions. The changes in the yolk and albumin pH were not uniform. The data from the constant temperature conditions were used to determine the coefficients of the egg quality prediction models, which consisted of the primary model controlling the change rate of the quality indicator at a temperature condition in differential equation form, and the secondary model controlling the change rate with temperature, which was in quadratic polynomial form. The models were applied to the data from the fluctuating temperature conditions, and the zeroth, third, and eighth order kinetic models described the stepwise change in the RWL, HU, and YI, respectively. The accuracy and bias factor values for the RWL, HU, and YI were 1.116 and 0.940, 1.028 and 1.001, and 1.038 and 0.966, respectively. It can be concluded that the models can be used to predict egg freshness in terms of the RWL, HU, and YI at any temperature condition with in the range of 5 to 30°C during storage. [ABSTRACT FROM AUTHOR]

Recently, temporal changes in Aerosol Optical Thickness (AOT) have been investigated based on model simulations, satellite and ground-based observations. Most AOT trend studies used monthly or annual arithmetic means that discard details of the generally right-skewed AOT distributions. Potentially, such results can be biased by extreme values (including outliers). This study additionally uses percentiles (i.e., the lowest 5%, 25%, 50%, 75% and 95% of the monthly cumulative distributions fitted to Aerosol Robotic Network (AERONET)-observed and ECHAM/MESSy Atmospheric Chemistry (EMAC)-model simulated AOTs) that are less affected by outliers caused by measurement error, cloud contamination and occasional extreme aerosol events. Since the limited statistical representativeness of monthly percentiles and means can lead to bias, this study adopts the number of observations as a weighting factor, which improves the statistical robustness of trend estimates. By analyzing the aerosol composition of AERONET-observed and EMAC-simulated AOTs in selected regions of interest, we distinguish the dominant aerosol types and investigate the causes of regional AOT trends. The simulated and observed trends are generally consistent with a high correlation coefficient (R = 0.89) and small bias (slope±2σ = 0.75 ± 0.19). A significant decrease in EMAC-decomposed AOTs by water-soluble compounds and black carbon is found over the USA and the EU due to environmental regulation. In particular, a clear reversal in the AERONET AOT trend percentiles is found over the USA, probably related to the AOT diurnal cycle and the frequency of wildfires. In most of the selected regions of interest, EMAC-simulated trends are mainly attributed to the significant changes of the dominant aerosols; e.g., significant decrease in sea salt and water soluble compounds over Central America, increase in dust over Northern Africa and Middle East, and decrease in black carbon and organic carbon over Australia. [ABSTRACT FROM AUTHOR]

This investigation examines aerosol dynamics during major fine mode aerosol transboundary pollution events in South Korea primarily during the KORUS-AQ campaign from May 1 – June 10, 2016, particularly when cloud fraction was high and/or fog was present to quantify the change in aerosol characteristics due to near-cloud or fog interaction. We analyze the new AERONET Version 3 data that have significant changes to cloud screening algorithms, allowing many more fine-mode observations in the near vicinity of clouds or fog. Case studies for detailed investigation include May 25–26, 2016 when cloud fraction was high over much of the peninsula, associated with a weak frontal passage and advection of pollution from China. These cloud-influenced Chinese transport dates also had the highest aerosol optical depth (AOD), surface PM 2.5 concentrations and fine mode particle sizes of the entire campaign. Another likewise cloud/high relative humidity (RH) case is June 9 and 10, 2016 when fog was present over the Yellow Sea that appears to have affected aerosol properties well downwind over the Korean peninsula. In comparison we also investigated aerosol properties on air stagnation days with very low cloud cover and relatively low RH (May 17 & 18, 2016), when local Korean emissions dominated. Aerosol volume size distributions show marked differences between the transport days (with high RH and cloud influences) and the local pollution stagnation days, with total column-integrated particle fine mode volume being an order of magnitude greater on the pollution transport dates. The PM 2.5 over central Seoul were significantly greater than for coastal sites on the transboundary transport days yet not on stagnation days, suggesting additional particle formation from gaseous urban emissions in cloud/fog droplets and/or in the high RH humidified aerosol environment. Many days had KORUS-AQ research aircraft flights that provided observations of aerosol absorption, particle chemistry and vertical profiles of extinction. AERONET retrievals and aircraft in situ measurements both showed high single scattering albedo (weak absorption) on the cloudy or cloud influenced days, plus aircraft profile in situ measurements showed large AOD enhancements (versus dried aerosol) at ambient relative humidity (RH) on the pollution transport days, consistent with the significantly larger fine mode particle radii and weak absorption. • Highest AOD and PM 2.5 over S. Korea had significant cloud cover and/or sea fog. • Particle volume was at least 10 times larger on high RH pollution transport days. • Particle SSA was high (0.97–0.99 in mid-visible) on pollution transport days. • The PM 2.5 was higher over central Seoul than the coast during pollution transport. [ABSTRACT FROM AUTHOR]