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The occurrence of pathogen bacteria in surface waters is a threat to public health worldwide. In particular, inadequate sanitation resulting in high contamination of surface water with pathogens of fecal origin is a serious issue in developing countries such as Lao P.D.R. Despite the health implications of the consumption of contaminated surface water, the environmental fate and transport of pathogens of fecal origin and their indicators (Fecal Indicator Bacteria or FIB) are still poorly known in tropical areas. In this study, we used measurements of flow rates, suspended sediments and of the FIB Escherichia coli (E. coli) in a 60-ha catchment in Northern Laos to explore the ability of the Soil and Water Assessment Tool (SWAT) to simulate watershed-scale FIB fate and transport. We assessed the influences of 3 in-stream processes, namely bacteria deposition and resuspension, bacterial regrowth, and hyporheic exchange (i.e. transient storage) on predicted FIB numbers. We showed that the SWAT model in its original version does not correctly simulate small E. coli numbers during the dry season. We showed that model's performance could be improved when considering the release of E. coli together with sediment resuspension. We demonstrated that the hyporheic exchange of bacteria across the Sediment-Water Interface (SWI) should be considered when simulating FIB concentration not only during wet weather, but also during the dry season, or baseflow period. In contrast, the implementation of the regrowth process did not improve the model during the dry season without inducing an overestimation during the wet season. This work thus underlines the importance of taking into account in-stream processes, such as deposition and resuspension, regrowth and hyporheic exchange, when using SWAT to simulate FIB dynamics in surface waters.

The goal of this study was to investigate the optimal pH and temperature allowing enhanced nitrification in communities of nitrifying bacteria in full-scale wastewater treatment plants (WWTPs). Although maximum nitrification of activated sludge in WWTPs was achieved using similar optimal conditions, nitrification performance was uniquely influenced by simultaneous variations in temperature and pH. These results led to development of different model equations predicting the combined effects of temperature and pH on nitrification rates at WWTPs, reflecting the propensity of nitrifying bacterial communities to flourish under different conditions. Different end products of nitrification resulted not only from certain factors such as pH and temperature, but from differences in proportions of nitrifying bacteria among total bacteria. Therefore, proper adjustment of optimal pH and temperature in nitrifying bacteria communities can provide an implementable approach to improve nitrification performance of WWTPs, incorporating those specific conditions shown to favor the acclimatization of certain nitrifying bacteria.

The goal of this study was to investigate the bacterial community associated with a pilot-scale thermophilic aerobic digestion (TAD) reactor treating sewage sludge. The digestion system removed up to approximately 30% of volatile solids (VS); VS and total solids (TS) decreased from 38.4 to 26.9 g/L and from 51.2 to 43.8 g/L, respectively, and the ratio of VS/TS declined from 75.4% to 62.8%. Coincident with the thermal reduction of sludge, 16S rRNA clone library data showed that a significant shift occurred in the bacterial community composition with the selection of the Firmicutes and Deinococcus-Thermus families as well as a marked decrease in the relative abundance of a large part of bacterial taxa such as Proteobacteria. A unique bacterial community in the TAD reactor developed resulting from specific environmental pressures such as thermal stress. A predominance of thermophilic bacteria belonging to Bacillus sp., Geobacillus sp., Thermaerobacter sp. and Thermus thermophilus sp. suggest their putative roles for potentially high thermophilic degradation of sewage sludge.

Adapting best management practices (BMPs) is influenced by target reduction efficiency BMP size, and BMP type. The System for Urban Storm water Treatment and Analysis INtegration (SUSTAIN) model was evaluated to determine optimal size and type of BMP with monitoring results from a commercial area and a public park in Korea. The hydrology model in SUSTAIN was tested in a commercial area (impervious area: 85%) and a public park (impervious area: 36%) in South Korea. A sensitivity analysis revealed that the significant parameters for total flow were impervious area Manning’s roughness (IMPN) and saturated hydraulic conductivity (HYDCON); and those for peak flow were IMPN, Manning’s roughness of conduit (ROUGH) and HYDCON. The observed average run-off ratios of the two study sites were 0.59 and 0.30 for the commercial area and the public park, respectively. In contrast, the simulated average run-off ratios were 0.53 and 0.22, respectively. The SUSTAIN hydrology model was also evaluated statistically b...

BACKGROUND Epidermal growth factor (EGF) has been known to induce epithelial–mesenchymal transition (EMT) and prostate cancer cell progression. However, a detailed underlying mechanism by which EGF induces EMT and prostate cancer cell progression remained to be answered. Hypoxia-inducible factor (HIF)-1α and TWIST1 are transcription factors implicated in EMT and cancer metastasis. The purpose of this study is to determine the underlying mechanism of EGF-induced TWIST1 expression and prostate cancer invasion. METHODS siRNAs were used to silence genes. Immunoblotting, quantitative RT-PCR and immunofluorescence analysis were used to examine protein or mRNA expression. Modified Boyden chamber and invasion assay kit with Matrigel-coated inserts were used to determine prostate cancer cell migration and invasion, respectively. RESULTS We observed that EGF induced HIF-1α expression and morphological change of prostate cancer epithelial cells to mesenchymal cells. Silencing HIF-1α expression dramatically reduced EGF-induced TWIST1 expression and prostate cancer cell EMT. Conversely, transfection of the cells with HIF-1α siRNA reversed the reduced E-cadherin expression by EGF. Pretreatment of the cells with pharmacological inhibitors of reactive oxygen species [ROS, N-acetylcysteine (NAC)] and STAT3 (WP1066) but not p38 MAPK (SB203580) significantly reduced EGF-induced HIF-1α mRNA and protein expression. Further, pretreatment of the cells with NAC attenuated EGF-induced STAT3 phosphorylation. In addition, we showed that TWIST1 mediated EGF-induced N-cadherin expression, leading to prostate cancer invasion. CONCLUSIONS We demonstrate a mechanism by which EGF promotes prostate cancer cell progression through a ROS/STAT3/HIF-1α/TWIST1/N-cadherin signaling cascade, providing novel biomarkers and promising therapeutic targets for prostate cancer cell progression. Prostate 74:528–536, 2014. © 2014 Wiley Periodicals, Inc.

Blocking the natural bi-directional flow in an estuarine system using an artificial dyke has commonly caused serious water quality problems. In the southwestern part of South Korea, a parallel triple-reservoir system was constructed by blocking the mouth of three different rivers (Yeongsan, Okcheon, and Kumja), which were then interconnected using two open channels. This system has experienced a deterioration in water quality due to pollutants accumulated from the upper watershed, and has continually discharged pollutant loads to the outer ocean. Therefore, the objective of this study is to establish an effective dam operation plan for reducing nutrient loads released from the integrated reservoir. In this study, the CE-QUAL-W2 model, which is a 2-dimentional hydrodynamic and water quality model, was applied to predict the pollutant load released from each reservoir in response to different flow scenarios for the interconnecting channel. The model was calibrated using two novel methods: a sensitivity analysis to determine meaningful model parameters, and a pattern search to optimize the parameters. From the scenario analysis using flow control, it was determined that the total nitrogen (TN) and total phosphorus (TP) loadings could be reduced by 27.2% and 6.6%, respectively, under the optimal channel flow scenario by regulating the chlorophyll-a concentration in the reservoir. The results confirm that effective dam operation could contribute to a decrease in pollutant loads in the receiving seawater body. As such, this study suggests operational strategies for a multi-reservoir system that can be used to reduce the nutrient load being discharged from reservoirs.

The indoor air quality of subway systems can significantly affect the health of passengers since these systems are widely used for short-distance transit in metropolitan urban areas in many countries. The particles generated by abrasion during subway operations and the vehicle-emitted pollutants flowing in from the street in particular affect the air quality in underground subway stations. Thus the continuous monitoring of particulate matter (PM) in underground station is important to evaluate the exposure level of PM to passengers. However, it is difficult to obtain indoor PM data because the measurement systems are expensive and difficult to install and operate for significant periods of time in spaces crowded with people. In this study, we predicted the indoor PM concentration using the information of outdoor PM, the number of subway trains running, and information on ventilation operation by the artificial neural network (ANN) model. As well, we investigated the relationship between ANN's performance and the depth of underground subway station. ANN model showed a high correlation between the predicted and actual measured values and it was able to predict 67∼80% of PM at 6 subway station. In addition, we found that platform shape and depth influenced the model performance.

Mathematical models have been developed to obtain a better understanding of membrane fouling mechanisms. However, those models could not simulate the membrane fouling behaviors accurately because of the large number of fitting parameters related to feed water quality and flow pattern in a membrane filtration system. In this study, we developed a deep neural network (DNN) to model membrane fouling during nanofiltration (NF) and reverse osmosis (RO) filtration using in-situ fouling image data from optical coherence tomography (OCT). The performance of the DNN model was compared with that of existing mathematical models. In total, 13,708 high-resolution fouling layer images were used to develop the DNN model and validate the model performance. The DNN model was trained to simulate both organic fouling growth and flux decline, and it reproduced two- or three-dimensional images of the organic fouling growth. The DNN model demonstrated better predictive performance than the existing mathematical models. It achieved an R2 value of 0.99 and RMSE of 2.82 μm for the fouling growth simulation and R2 of 0.99 and RMSE of 0.30 Lm−2h−1 for the flux decline simulation. Therefore, the data-driven approach is an alternative way to model the membrane fouling and flux decline processes under high-pressure filtrations.

Background: Rab coupling protein (RCP), also called family interacting protein 1 (Rab11fip1) is a protein encoded by the RAB11FIP1 gene and has been known to augment cancer tumorigenesis, invasion, and metastasis. Recently, RCP was reported to aggravate cancer cell invasion and metastasis by stabilizing beta1 integrin and inducing epithelial-mesenchymal transition (EMT) in breast and ovarian cancer. Further, a high RCP expression was significantly correlated with shorter overall survival and disease-free survival of HNSCC patients. However, the molecule mechanisms by which RCP increases HNSCC invasion and metastasis are unclear. In the present study, we demonstrate the role of RCP in oral cancer cell invasiveness and its underlying mechanism. Methods: Oral cancer YD-10B and YD-38 cells were transiently transfected with RCP constructs. siRNAs were used to analyze the role of specific proteins for Slug and Zeb1 expression. Immunoblotting and immunofluorescence were used to analyze protein expression. Matrigel-coated in vitro insert and wound healing assay were used to analyze cancer cell invasion and migration, respectively. Results: We observed that ectopic expression of RCP induces invasion of oral cancer cells. Conversely, silencing of RCP expression increased E-cadherin expression and reduced oral cancer cell invasion. In addition, RCP upregulated Zeb1 and Slug expression that is important for RCP-induced oral cancer cell EMT and invasion. Furthermore, we identified that silencing of beta1 integrin efficiently attenuates RCP-induced Zeb1 and Slug expression. In addition, we observed that a selective inhibitor of EGFR kinase activity, Gefitinib, significantly reduces RCP-induced Zeb1 and Slug expression and that RasN17 recovers RCP-induced Zeb1 expression. Finally, RCP increased the viability of oral cancer cells against a chemotherapeutic agent cisplatin. Conclusion: Collectively, we demonstrate that RCP augments oral cancer cell EMT and invasiveness through a beta1 integrin/EGFR/Ras/Slug and Zeb1 signaling axis, providing potential biomarkers for oral cancer patients therapy. Citation Format: Jin Young Kim, Kyung Hwa Cho, Bo Young Jeong, Zi Hae Song, Chang Gyo Park, Hoi Young Lee. RCP augments oral cancer cell invasion through Zeb1 and Slug expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2860.

The majority of chemotherapy treatments for lung cancer use cisplatin; however, its use is limited as it has several side-effects. Autophagy (or type II cell death) is an important mechanism by which programmed cell death occurs. The purpose of this study was to determine whether low-dose cisplatin treatment induces autophagy in lung cancer cells. We also examined whether autophagy inhibition results in p53-mediated apoptosis. NCI-H460 (wild-type p53) and NCI-H1299 (null-type p53) cells were treated with 5 or 20 µM cisplatin for 12, 24 or 48 h. An MTT assay was performed to measure the cell viability following cisplatin treatment. To detect cisplatin-induced autophagy, cell morphology (autophagic vacuole) and LC3 localization were examined. The outcome of autophagy inhibition was determined using 3-methyladenine (3-MA) to detect Annexin V (+), propidium iodide (PI) (-) and acridine orange (+) cells by FACS analysis. To determine whether cisplatin induced autophagy, we examined the role of p53 as a cell survival regulator in autophagy. Low-doses of cisplatin (5 µM) induced cell death and this was augmented by 3-MA in both cell lines. Autophagic vacuoles and cytoplasmic LC3 formation was more evident in H460 cells than in H1299 cells. The induction of autophagy by low-dose cisplatin was increased by 2-fold in H460 compared to H1299 cells. However, the tests for apoptosis showed no difference between the 2 cell lines. Following 3-MA pretreatment, cisplatin-induced autophagy was found to be markedly reduced (a 3-fold reduction) in wild-type p53 compared to null-type p53 cells. However, cisplatin-induced apoptosis increased in wild-type p53 compared to null-type p53 cells. Autophagy induction and apoptotic shift after autophagy inhibition may be mediated by p53 activation in lung cancer cells treated with low-dose cisplatin.

Over a 3 year period, interactions between nitrifying bacterial communities and the operational parameters of a full-scale wastewater treatment plant were analyzed to assess their impact on nitrification performance. Throughout the study period, nitrification fluctuated while Nitrosomonas europaea and Nitrosomonas nitrosa, the two major ammonia oxidizing bacteria (AOB) communities, showed resistance to changes in operational and environmental conditions. Nitrobacter populations mostly exceeded those of Nitrospira within nitrite oxidizing bacteria (NOB). Meanwhile, principal component analysis (PCA) results revealed that a close association between Nitrobacter and nitrite concentration as well as a direct correlation between the quantity of AOB and influent SCN- concentration. The serial shifts of data points over time showed that the nitrification of a full-scale treatment plant has been gradually suppressed by the influence of influent COD and phenol concentrations.

The effect of bentonite and sand, as natural capping agents, on the fluxes of nutrients and trace metals across the sediment-water interface was studied through sediment incubation, and the ecotoxicological impact was assessed by using Daphnia magna. Bentonite and sand were layered on the sediment at 15, 75, and 225 mg cm(-2), and the concentration of cations, nutrients, and trace metals was measured. Sediment incubation showed that bentonite reduced the N flux but increased the P flux as a result of dissolution of non-crystalline P from bentonite, while sand slightly decreased the N fluxes but not the P flux. The concentration of Na increased in the overlying water with increasing application rates of bentonite, while that of Ca decreased. However, regardless of the rate of sand application, concentrations of all cation species remained unchanged. The concentration of As and Cr increased with bentonite application rate but decreased with sand. Both capping materials suppressed fluxes of Cd, Cu, Ni, and Zn compared to control, and the extent of suppression was different depending on the trace metal species and capping agents used. During sediment incubation, the survival rate of D. magna significantly decreased in bentonite suspension but began to decrease at the end in sand suspension. Sediment capping of mildly polluted sediments by using bentonite and sand lowered the level of nutrients and trace metals. However, unexpected or undesirable side effects, such as influxes of P and As from bentonite to the overlying water and a possibility of toxic impacts to aquatic ecosystems, were observed, suggesting that capping agents with an adequate assessment of their side effects and toxicity should be predetermined for site-specific sediment management strategies.

Hippo/YAP signaling is implicated in tumorigenesis and progression of various cancers. By inhibiting a plethora signaling cascades, resveratrol has strong anti-tumorigenic and anti-metastatic activity. In the present study, we demonstrate that resveratrol decreases the expression of YAP target genes. In addition, our data showed that resveratrol attenuates breast cancer cell invasion through the activation of Lats1 and consequent inactivation of YAP. Strikingly, we also demonstrate that resveratrol inactivates RhoA, leading to the activation of Lats1 and induction of YAP phosphorylation. Further, resveratrol in combination with other agents that inactivate RhoA or YAP showed more marked suppression of breast cancer cell invasion compared with single treatment. Collectively, these findings indicate the beneficial effects of resveratrol on breast cancer patients by suppressing the RhoA/Lats1/YAP signaling axis and subsequently inhibiting breast cancer cell invasion.

PAHs are potentially carcinogenic substances that are persistent in the environment. Increasing concentrations of PAHs were observed due to rapid urbanization, thus; monitoring PAHs concentrations is necessary. However, it is expensive to conduct intensive monitoring activities of a large number of PAHs. This study addressed this issue by developing a multimedia model coupled with a hydrological model (i.e., Soil and Water Assessment Tool (SWAT)) for Taehwa River (TR) watershed in Ulsan, the industrial capital of South Korea. The hydrologic module of the SWAT was calibrated, and further used to simulate the fate and transport of PAHs in soil and waterbody. The model demonstrated that the temporal or seasonal variation of PAHs in soil and waterbody can be well reproduced. Meanwhile, the spatial distribution of PAHs showed that urban areas in TR watershed have the highest PAH loadings compared to rural areas. Sensitivity analyses of the PAH soil and PAH water parameters were also able to determine the critical processes in TR watershed: degradation, deposition, volatilization, and wash off mechanism. We hope that this model will be able to aid the stakeholders in: regulating PAH concentrations emitted by various sources; and also apply the model to other Persistent Organic Pollutants (POPs).

The goal of this study was to investigate the individual and combined effects of temperature, salinity, and pressure on permeate flux and salt rejection of the reverse osmosis (RO) process used for reclamation of tunnel construction wastewater. Regardless of changes in temperature, higher operating pressures enhanced both permeate flux and salt rejection, while effects of temperatures on performance varied depending on the operating pressures. Increasing temperatures to less than 35 bar did not improve the permeate flux and salt rejection, while to more than 50 bar led to higher rejection as well as more permeate flux of reclaimed wastewater. Based on analysis of model equations developed, the extent of flux and salt rejection required for reuse of the reclaimed wastewater occurred under different optimal conditions depending on variations in seasons and salinity of wastewater. In particular, it was necessary to add additional pressure exceeding 50 bar or increase the temperature to over 20°C when wastewater of more than 20‰ salinity flows into the treatment system. Adjustment of influential variables can provide an implementable approach to improve operation of the RO process as well as optimize a process for practical construction on-site applications.

Renewed harmful algal blooms and hypoxia in Lake Erie have drawn significant attention to phosphorus loads, particularly increased dissolved reactive phosphorus (DRP) from highly agricultural watersheds. We use the Soil and Water Assessment Tool (SWAT) to model DRP in the agriculture-dominated Sandusky watershed for 1970-2010 to explore potential reasons for the recent increased DRP load from Lake Erie watersheds. We demonstrate that recent increased storm events, interacting with changes in fertilizer application timing and rate, as well as management practices that increase soil stratification and phosphorus accumulation at the soil surface, appear to drive the increasing DRP trend after the mid-1990s. This study is the first long-term, detailed analysis of DRP load estimation using SWAT.

Different numerical schemes for the fate and transport models of fecal indicator bacteria (FIB) were used to predict the concentration of FIB in a creek, which were then compared to a steady state model (QUAL2E). Escherichia coli (EC) and enterococci bacteria (ENT) were selected as representative FIB to compare the model performance under different flow and weather conditions in the Gwangju Creek in Korea. The results revealed that model accuracy of the forward time centered space (FTCS) scheme is the highest compared to the upstream, Dufort-Frankel, Crank-Nicolson methods and steady state model (QUAL2E) under dry weather conditions. In wet weather conditions, however, the upstream scheme shows the best performance among the five models. The upstream scheme thus represented a potential method for predicting the fate and transport of FIB originating from nonpoint sources during the rainy season. This study demonstrates that prediction results could vary in response to different numerical schemes a...

Faulty field sensors cause unreliability in the observed data that needed to calibrate and assess hydrology models. However, it is illogical to ignore abnormal or missing values if there are limited data available. This study addressed this problem by applying data imputation to replace incorrect values and recover missing streamflow information in the dataset of the Samho gauging station at Taehwa River (TR), Korea from 2004 to 2006. Soil and Water Assessment Tool (SWAT) and two machine learning techniques, Artificial Neural Network (ANN) and Self Organizing Map (SOM), were employed to estimate streamflow using reasonable flow datasets of Samho station from 2004 to 2009. The machine learning models were generally better at capturing high flows, while SWAT was better at simulating low flows.

Summary Seasonal and spatial variation in the genotypic rich- ness of 3480 Escherichia coli isolates obtained from the Yeongsan River basin in South Korea was inves- tigated by using the horizontal fluorophore-enhanced rep-PCR (HFERP) DNA fingerprinting technique. The relationship between 60 E. coli isolates from each of 58 freshwater samples was determined by using multidimensional scaling (MDS) analysis and self- organized maps (SOMs). The MDS analysis, done based on HFERP DNA fingerprints, showed that E. coli isolates obtained in October through Decem- ber clustered tightly, while those obtained in other sampling periods were more genetically diverse. However, site-specific E. coli genotypes were not observed. SOMs analysis, done using the 10 most frequently isolated E. coli genotypes, showed the occurrence of season-specific E. coli genotypes and the main SOMs clusters were most influenced by tem- perature, strain diversity and biochemical oxygen demand. Diversity among E. coli genotypes tended to decrease as water temperature decreased, and the numbers of E. coli genotypes observed in urban area were greater, more diverse and less dependent on water temperature than those obtained from agricul- tural areas. Taken together, our findings indicate that that an ecological approach needs to be considered in order to obtain a better understanding of E. coli community dynamics in the environment and that SOMs analysis is useful to visualize the multidimen- sional dependent variables that are influencing the types and dynamics of specific E. coli genotypes in the environment.

Summary Escherichia coli release from streambed sediments may substantially affect microbial water quality. Models of E. coli release and transport commonly use a single set of parameters for the whole stream or reservoir, yet little is known about the magnitude and sources of the variability of parameters of the streambed bacteria release. The objectives of this work were: (a) to obtain and compare parameters of streambed E. coli resuspension in three stream reaches with distinctly different bottom sediment textures, and (b) to see whether the modeling of streambed E. coli resuspension with reach-specific parameters could provide substantially better accuracy than modeling with a single set of parameters. Sediment particle size distributions and the streambed E. coli concentrations were measured along a first-order creek in the USDA-ARS OPE3 experimental watershed in Maryland. Afterwards, 80 m3 of water were released into the creek at a rate of 60 L per second in four equal allotments separated by 1–3 min intervals. Flow rates and E. coli concentrations were monitored with automated samplers at the ends of the three reaches with a total length of 630 m. A high concentration of streambed E. coli (“hotspot”) resuspended within the first reach caused a pulse of high E. coli concentrations that propagated along the creek without substantial attenuation; inputs of sediment-borne E. coli from the next two reaches were relatively small. The E. coli transport model included one-dimensional Saint–Venant and advective–dispersive equations. The calibrated roughness coefficient values were comparable for the three reaches, whereas the critical stress and the entrainment rate differed among reaches by a half order and an order of magnitude, respectively. Overall, better accuracy was observed when the model contained reach-specific parameters. Additional research is needed to understand which and how sediment properties affect parameters of streambed E. coli release into the water column.

This study reveals land-use factors that explain stream water quality during wet and dry weather conditions in a large river basin using two different linear models-multiple linear regression (MLR) models and constrained least squares (CLS) models. Six land-use types and three topographical parameters (size, slope, and permeability) of the watershed were incorporated into the models as explanatory variables. The suggested models were then demonstrated using a digitized elevation map in conjunction with the land-use and the measured concentration data for Escherichia coli (EC), Enterococci bacteria (ENT), and six heavy metal species collected monthly during 2007-2008 at 50 monitoring sites in the Yeongsan Watershed, Korea. The results showed that the MLR models can be a powerful tool for predicting the average concentrations of pollutants in stream water (the Nash-Sutcliffe (NS) model efficiency coefficients ranged from 0.67 to 0.95). On the other hand, the CLS models, with moderately good prediction performance (the NS coefficients ranged 0.28-0.85), were more suitable for quantifying contributions of respective land-uses to the stream water quality. The CLS models suggested that industrial and urban land-uses are major contributors to the stream concentrations of EC and ENT, whereas agricultural, industrial, and mining areas were significant sources of many heavy metal species. In addition, the slope, size, and permeability of the watershed were found to be important factors determining the extent of the contribution from each land-use type to the stream water quality. The models proposed in this paper can be considered useful tools for developing land cover guidelines and for prioritizing locations for implementing management practices to maintain stream water quality standard in a large river basin.

As a representative urban stream in Korea, the Gwangju (GJ) stream suffers from chronic fecal contamination. In this study, to characterize levels of fecal pollution in the GJ stream, the monthly monitoring data for seven years (from 2001 to 2007) and the hourly monitoring data from two field experiments were examined with respect to seasonal/daily variations and spatial distribution under wet and dry weather conditions. This research revealed that concentrations of fecal indicator bacteria strongly varied depending on the prevalent meteorological conditions. That is, during the dry daytime, fecal indicator bacteria concentrations decreased due to inactivation from solar irradiation, but rapidly increased in the absence of sunlight, suggesting external source inputs. In addition, bacterial concentrations substantially increased during rainfall events, due probably to a major contribution from combined sewer overflow. The observations in this study can be useful for implementing fecal pollution management strategies and for predicting fecal contamination as a function of meteorological conditions.

Gwangju Creek (GJC) in Korea, which drains a highly urbanized watershed, has suffered from substantial fecal contamination, thereby limiting the beneficial use of the water in addition to threatening public health. In this study, to quantitatively estimate the sinks and sources of fecal indicator bacteria (FIB) in GJC under varying meteorological conditions, two FIB (i.e., Escherichia coli and enterococci bacteria) were monitored hourly for 24 h periods during both wet and dry weather conditions at four sites along GJC, and the collected data was subsequently used to develop a spatiotemporal FIB prediction model. The monitoring data revealed that storm washoff and irradiational die-off by sunlight are the two key processes controlling FIB populations in wet and dry weather, respectively. FIB populations significantly increased during precipitation, with greater concentrations occurring at higher rainfall intensity. During dry weather, FIB populations decreased in the presence of sunlight in daytime but quickly recovered at nighttime due to continuous point-source inputs. In this way, the contributions of the key processes (i.e., irradiational die-off by sunlight, settling, storm washoff, and resuspension) to the FIB levels in GJC under different meteorological conditions were quantitatively estimated using the developed model. The modeling results showed that the die-off by sunlight is the major sink of FIB during the daytime in dry weather with a minor contribution from the settling process. During wet weather, storm washoff and resuspension are equally important processes that are responsible for the substantial increase of FIB populations.

The small GTP-binding protein Rab25 is associated with tumor formation and progression. However, recent studies have shown discordant effects of Rab25 on cancer cell progression depending on cell lineage. In the present study, we elucidate the underlying mechanisms by which Rab25 induces cellular invasion. We demonstrate that Rab25 increases β1 integrin levels and subsequent activation of EGFR and upregulation of VEGF-A expression, leading to increased Snail expression, epithelial-to-mesenchymal transition and cancer cell invasiveness. Strikingly, we identify that Snail mediates Rab25-induced cancer cell invasiveness through fascin expression and that ectopic expression of Rab25 aggravates metastasis of ovarian cancer cells to the lung. We thus demonstrate a novel role of a β1 integrin/EGFR/VEGF-A/Snail signaling cascade in Rab25-induced cancer cell aggressiveness through induction of fascin expression, thus providing novel biomarkers and potential therapeutic targets for Rab25-expressing cancer cells.

This study focused on the analysis of As levels in human hair samples collected from six villages in the Kandal Province of Cambodia. Of interest were the influence of, and interactions among, certain factors affecting As intake into the human body: As concentrations in groundwater, period of groundwater consumption, age and gender. The results revealed As levels in human hair ranging from 0.06 to 30 μg g −1 with median and arithmetic mean values of 0.61 and 3.20 μg g −1 ( n = 68), respectively. Furthermore, a linear relationship was found between As concentrations in human hair and in the local groundwater. Arsenic (III) is the dominant species in Kandal groundwater, constituting in most cases at least 60% of the total As. Arsenic concentration ranged from 5 to 1543 μg L −1 , with the median value 348 μg L −1 and arithmetic mean 454 μg L −1 . In large rural, poor areas holding most of Kandal’s 1.1 million people, up to 2 in 1000 people are believed to be at risk of cancer through the As-enriched water they drink. A toxicity risk assessment provides a hazard quotient (HQ) equaling 5.12, also a clear indication of non-carcinogenic exposure risk. On the authors’ visit to Kampong Kong commune, Kandal Province, cases of arsenicosis were diagnosed in patients as a result of drinking As-enriched groundwater.

The present study proposes a methodology for determining the effective dispersion coefficient based on the field measurements performed in Gwangju (GJ) Creek in South Korea which is environmentally degraded by the artificial interferences such as weirs and culverts. Many previous works determining the dispersion coefficient were limited in application due to the complexity and artificial interferences in natural stream. Therefore, the sequential combination of N-Tank-In-Series (NTIS) model and Advection-Dispersion-Reaction (ADR) model was proposed for evaluating dispersion process in complex stream channel in this study. The series of water quality data were intensively monitored in the field to determine the effective dispersion coefficient of E. coli in rainy day. As a result, the suggested methodology reasonably estimates the dispersion coefficient for GJ Creek with 1.25 m2/s. Also, the sequential combined method provided Number of tank-Velocity-Dispersion coefficient (NVD) curves for convenient evaluation of dispersion coefficient of other rivers or streams. Comparing the previous studies, the present methodology is quite general and simple for determining the effective dispersion coefficients which are applicable for other rivers and streams.

The Yeongsan (YS) Reservoir is an estuarine reservoir which provides surrounding areas with public goods, such as water supply for agricultural and industrial areas and flood control. Beneficial uses of the YS Reservoir, however, are recently threatened by enriched non-point and point source inputs. A series of multivariate statistical approaches including principal component analysis (PCA) were applied to extract significant characteristics contained in a large suite of water quality data (18 variables monthly recorded for 5 years); thereby to provide the important phenomenal information for establishing effective water resource management plans for the YS Reservoir. The PCA results identified the most important five principal components (PCs), explaining 71% of total variance of the original data set. The five PCs were interpreted as hydro-meteorological effect, nitrogen loading, phosphorus loading, primary production of phytoplankton, and fecal indicator bacteria (FIB) loading. Furthermore, hydro-meteorological effect and nitrogen loading could be characterized by a yearly periodicity whereas FIB loading showed an increasing trend with respect to time. The study results presented here might be useful to establish preliminary strategies for abating water quality degradation in the YS Reservoir.

Statistical regression models involve linear equations, which often lead to significant prediction errors due to poor statistical stability and accuracy. This concern arises from multicollinearity in the models, which may drastically affect model performance in terms of a trade-off scenario for effective water resource management logistics. In this paper, we propose a new methodology for improving the statistical stability and accuracy of regression models, and then show how to cope with pitfalls in the models and determine optimal parameters with a decreased number of predictive variables. Here, a comparison of the predictive performance was made using four types of multiple linear regression (MLR) and principal component regression (PCR) models in the prediction of chlorophyll-a (chl-a) concentration in the Yeongsan (YS) Reservoir, Korea, an estuarine reservoir that historically suffers from high levels of nutrient input. During a 3-year water quality monitoring period, results showed that PCRs could be a compact solution for improving the accuracy of the models, as in each case MLR could not accurately produce reliable predictions due to a persistent collinearity problem. Furthermore, based on R2 (goodness of fit) and F-overall number (confidence of regression), and the number of explanatory variables (R-F-N) curve, it was revealed that PCR-F(7) was the best model among the four regression models in predicting chl-a, having the fewest explanatory variables (seven) and the lowest uncertainty. Seven PCs were identified as significant variables, related to eight water quality parameters: pH, 5-day biochemical oxygen demand, total coliform, fecal indicator bacteria, chemical oxygen demand, ammonia–nitrogen, total nitrogen, and dissolved oxygen. Overall, the results not only demonstrated that the models employed successfully simulated chl-a in a reservoir in both the test and validation periods, but also suggested that the optimal parameters should cautiously be considered in the design of regression models.

As a means of optimizing desalination processes, site-specificity in the determination of seawater quality conditions is a crucial point for improving the overall energy efficiency of a seawater reverse osmosis (SWRO) process. To this end, field studies were carried out at 16 sampling sites along the shoreline in South Korea to investigate the site-specific features of seawater quality. Also, two mathematical models were developed for the simulation of SWRO processes dependent on seawater quality in macroscopic and microscopic contexts, respectively. As a result, the microscopic dynamic model revealed that concentration polarization in the vicinity of the membrane surface and permeate concentration are affected by the feed seawater concentration and pressure. Then, the application of Fujairah SWRO plant operation data to the macroscopic simulation of a non-isobaric SWRO process model resulted in significant energy savings in terms of operational pressure savings, reducing 0.3 bar from the annual average value in the first pass operational pressure. These findings suggest that a cost-effective SWRO operation can be feasible using non-isobaric pressure controls by considering site-specific feed seawater concentrations. Results of the study presented here can be applied to improving the energy efficiency in SWRO plants through the optimization of pressurized systems.

Background Cancer metastasis is a multi-step event including epithelial-to-mesenchymal transition (EMT). Breast cancer metastasis suppressor 1 (BRMS1) is a novel metastasis suppressor protein without anti-proliferating activity. However, a detailed underlying mechanism by which BRMS1 attenuates cancer cell EMT and invasion remained to be answered. In the present study, we report an additional mechanism by which BRMS1 attenuates Transforming growth factor-beta1 (TGF-β1)-induced breast cancer cell EMT and invasion. Methods Experimental analysis involving chromosome immunoprecipitation (ChIP) and luciferase reporter assays were used to validate hypoxia inducible factor-1alpha (HIF-1α) as a transcriptional regulator of TWIST1 and Snail. Quantitative RT-PCR was used to analyze transcript expression. Immunoblotting and immunofluorescence were used to analyze protein expression. Matrigel-coated in vitro invasion insert was used to analyze cancer cell invasion. Results BRMS1 strongly inhibited TGF-β1-induced breast cancer cell EMT and invasion. Unexpectedly, we observed that BRMS1 downregulates not only TWIST1 but also Snail expression, thereby inhibiting breast cancer cell invasion. In addition, we provide evidence that HIF-1α is required for Snail and TWIST1 expression. Further, BRMS1 reduced TGF-β1-induced HIF-1α transcript expression through inactivation of nuclear factor kappaB (NF-κB). Conclusion Collectively, the present study demonstrates a mechanical cascade of BRMS1 suppressing cancer cell invasion through downregulating HIF-1α transcript and consequently reducing Snail and TWIST1 expression.

Stress hormone norepinephrine (NE) has been associated with acquisition of cancer progression, and naturally occurring phytoalexin resveratrol (REV) has been known to suppress cancer growth and progression. In the present study, we determine the effect of REV on NE-induced ovarian cancer invasiveness. Pretreatment of REV significantly inhibited NE-induced ovarian cancer cell epithelial-to-mesenchymal transition with concomitant recovery of E-cadherin expression. In addition, our data showed that REV downregulates NE-induced human telomerase reverse transcriptase (hTERT) expression through inhibiting Src phosphorylation and HIF-1α expression. Further, REV reduced NE-induced Slug expression and subsequent ovarian cancer invasion. More importantly, combined treatment of REV with a pharmacological inhibitor of beta adrenergic receptor significantly attenuated NE-induced ovarian cancer invasion compared to single treatment. Therefore, we demonstrate interference of a Src and HIF-1α/hTERT/Slug signaling cascade by REV, providing potential therapeutic targets and inhibition of ovarian cancer.

Pemetrexed, a multitarget antifolate used to treat malignant mesothelioma and non-small cell lung cancer (NSCLC), has been shown to stimulate autophagy. In this study, we determined whether autophagy could be induced by pemetrexed and simvastatin cotreatment in malignant mesothelioma and NSCLC cells. Furthermore, we determined whether inhibition of autophagy drives apoptosis in malignant mesothelioma and NSCLC cells. Malignant mesothelioma MSTO-211H and A549 NSCLC cells were treated with pemetrexed and simvastatin alone and in combination to evaluate their effect on autophagy and apoptosis. Cotreatment with pemetrexed and simvastatin induced greater caspase-dependent apoptosis and autophagy than either drug alone in malignant mesothelioma and NSCLC cells. 3-Methyladenine (3-MA), ATG5 siRNA, bafilomycin A, and E64D/pepstatin A enhanced the apoptotic potential of pemetrexed and simvastatin, whereas rapamycin and LY294002 attenuated their induction of caspase-dependent apoptosis. Our data indicate that pemetrexed and simvastatin cotreatment augmented apoptosis and autophagy in malignant mesothelioma and NSCLC cells. Inhibition of pemetrexed and simvastatin-induced autophagy was shown to enhance apoptosis, suggesting that this could be a novel therapeutic strategy against malignant mesothelioma and NSCLC.

To characterize fluorescent dissolved organic matter (FDOM) in Yeongsan River in Korea, 110 water samples were acquired from March 2008 to November 2009 around the watershed. Excitation emission matrix data of fluorescence was obtained using spectrophotometric analysis and parallel factor (PARAFAC) model was used to characterize FDOM. The spatiotemporal variation and effect on FDOM were studied using an exploratory analysis and analysis of variance (ANOVA). According to the spatial and seasonal characteristics, we used post hoc analysis to identify significantly different sites and season. The PARAFAC results identified three most important PARAFAC components explaining 95.32% of total variance of original data-set. Seasons and sites had a significant effect on PARAFAC Components I and II (p ≤ 0.05), whereas season had a significant effect on Component III (p ≤ 0.05). There was no significant interaction between seasons and sites for all the three PARAFAC components (p > 0.05). For Components I and II, summer season was significantly different from other seasons (p ≤ 0.05), whereas for Component III, the fall season was significantly different from winter and summer seasons (p ≤ 0.05). These results indicate that ANOVA and post hoc analysis in our study not only confirmed the results of previous studies, but also revealed differences in seasons and sites for identified FDOMs as a new information. The methodology proposed in this paper can be a useful tool for finding sources and sinks of FDOMs in a riverine system influenced by natural organic matter impairment.

Stress hormones have been implicated in both tumor initiation and progression. Human telomerase reverse transcriptase (hTERT) is overexpressed in cancer cells and associated with malignant tumor progression and poor outcome. We thus sought to determine whether the stress hormone norepinephrine (NE) could induce hTERT expression and subsequently ovarian cancer progression. Unexpectedly, NE induced hTERT transcript and protein expression, and subsequently ovarian cancer cell invasion. Pharmacologic inhibition of β2-adrenergic receptor 2 and protein kinase A, as well as silencing of hypoxia-inducible factor-1α and c-Myc expression, profoundly attenuated NE-induced hTERT expression. Strikingly, stimulation of the cells with NE or ectopic expression of hTERT induced expression of Slug, ovarian cancer cell epithelial-mesenchymal transition (EMT) and invasion. Silencing of hTERT expression abrogated NE-induced ovarian cancer cell invasion, EMT and Slug expression. In addition, silencing of Slug expression significantly inhibited NE- and hTERT-induced ovarian cancer cell EMT and invasion. Moreover, continuous exposure to NE was sufficient to enhance in vivo hTERT expression and metastasis of ovarian cancer cells to the lung. Finally, we provide evidence that hTERT links Src to Slug expression in NE-induced ovarian cancer EMT and metastasis. We thus demonstrate a novel role of hTERT in stress hormone-induced ovarian cancer aggressiveness through inducing Slug, providing novel biomarkers and potential therapeutic targets for ovarian cancer.

Biofouling is a crucial issue, and it causes seawater reverse osmosis membrane to deteriorate the performance of desalination. In this study, excitation emission matrix (EEM) fluorescence spectroscopy and parallel factor analysis (PARAFAC) were used to monitor the strength of biofouling on the fouled membrane which was obtained from real plant. Based on EEM and PARAFAC results of raw seawater, feed water, permeate, brine and fouled membrane, three components were identified as the major peaks: (1) microbial product-like materials at Ex/Em = 280/370 nm, (2) humic-like substances at Ex/Em = 330/420 nm, and (3) aromatic proteins at Ex/Em = 240/320 nm. Using the fluorescence intensity changes, the effects of replacing fouled RO membranes were found to be most significant at one of the components (Ex/Em = 270–300/350–380 nm) which could be considered the substances desorbed from fouled RO membrane. Compared to the data for salt rejection, this component monitoring of the brine EEM image is shown to be more sensitive than conductivity monitoring for predicting the biofouling strength during the desalination process.

Science Walden, which is inspired by two prominent literary works, namely, Walden by Henry David Thoreau (1817–1862) and Walden Two by Burrhus Frederic Skinner (1904–1990), is aimed at establishing a community that embodies humanistic values while embracing scientific advancement to produce renewable energy and water sources. This study attempts to capitalize on feces standard money (FSM) and artistic collaboration between scientists and artists as a means of achieving the forms of life depicted in Walden and Walden Two. On our campus, we designed and built a pavilion that serves as a laboratory where scientific advantages, design, and art are merged. In the pavilion, feces are processed in reactors and facilities for sustainable energy production, and rainwater is harvested and treated for use in daily life. Our application of design and art contributes to easing interaction between the general public and scientists because it visualizes an ambiguous theory and concretizes it into an understandable image.

Epidermal growth factor (EGF) has been known to induce epithelial-mesenchymal transition (EMT) and prostate cancer cell progression. However, a detailed underlying mechanism by which EGF induces EMT and prostate cancer cell progression remained to be answered. Hypoxia-inducible factor (HIF)-1α and TWIST1 are transcription factors implicated in EMT and cancer metastasis. The purpose of this study is to determine the underlying mechanism of EGF-induced TWIST1 expression and prostate cancer invasion.siRNAs were used to silence genes. Immunoblotting, quantitative RT-PCR and immunofluorescence analysis were used to examine protein or mRNA expression. Modified Boyden chamber and invasion assay kit with Matrigel-coated inserts were used to determine prostate cancer cell migration and invasion, respectively.We observed that EGF induced HIF-1α expression and morphological change of prostate cancer epithelial cells to mesenchymal cells. Silencing HIF-1α expression dramatically reduced EGF-induced TWIST1 expression and prostate cancer cell EMT. Conversely, transfection of the cells with HIF-1α siRNA reversed the reduced E-cadherin expression by EGF. Pretreatment of the cells with pharmacological inhibitors of reactive oxygen species [ROS, N-acetylcysteine (NAC)] and STAT3 (WP1066) but not p38 MAPK (SB203580) significantly reduced EGF-induced HIF-1α mRNA and protein expression. Further, pretreatment of the cells with NAC attenuated EGF-induced STAT3 phosphorylation. In addition, we showed that TWIST1 mediated EGF-induced N-cadherin expression, leading to prostate cancer invasion.We demonstrate a mechanism by which EGF promotes prostate cancer cell progression through a ROS/STAT3/HIF-1α/TWIST1/N-cadherin signaling cascade, providing novel biomarkers and promising therapeutic targets for prostate cancer cell progression.

In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over three times greater than any previously observed bloom. Here we show that long-term trends in agricultural practices are consistent with increasing phosphorus loading to the western basin of the lake, and that these trends, coupled with meteorological conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormally long residence times that incubated the bloom, and warm and quiescent conditions after bloom onset allowed algae to remain near the top of the water column and prevented flushing of nutrients from the system. We further find that all of these factors are consistent with expected future conditions. If a scientifically guided management plan to mitigate these impacts is not implemented, we can therefore expect this bloom to be a harbinger of future blooms in Lake Erie.

The Wachusett Reservoir is a primary drinking water resource for the greater Boston, Massachusetts, area. With a drainage area of 280 km 2 , the watershed has been gradually urbanized with increased residential, commercial, industrial, and transportation land uses. Increased impervious surface area as a result of urbanization results in increased runoff volume and pollutant loads to the reservoir. This study estimated annual stormwater pollutant mass loads in the watershed to prioritize sub-basins and to identify areas susceptible to stormwater pollution. Catchment Prioritization Index (CPI) was calculated using annual stormwater pollutant mass loads, which were further used to identify clustered hotspots through application of the Getis-Ord Gi * statistic. Validation with observed data showed higher levels of fecal coliform bacteria loading from identified hotspots. This approach will be useful to prioritize sub-basins for future (1) development of stormwater monitoring strategies and (2) best management practices (BMPs) in the watershed. 1.

Purpose C-reactive protein (CRP) has been implicated in various inflammatory and advanced malignant states. Increased serum CRP (s-CRP) levels have been shown to be associated with independent prognostic factors for survival in patients with advanced lung cancer. However, only few studies have focused on the role of CRP in pleural effusions. This study aimed to evaluate the diagnostic and prognostic value of pleural CRP (p-CRP) in lung cancer patients with malignant pleural effusion (MPE). Materials and Methods Pleural effusion (PE) samples were collected from patients with MPE (68 lung cancers; 12 extrathoracic tumors), and from 68 patients with various benign conditions (31 with pneumonia; 37 with tuberculosis). Concentrations of p- and s-CRP were measured by enzyme-linked immunosorbent assay. CRP level in pleural fluid and its association with survival were examined. Results p-CRP levels correlated with s-CRP levels (r=0.82, p

TGF-β1 induces epithelial-mesenchymal transition (EMT) to stimulate cancer cell progression, and TWIST1 is a critical regulator of EMT. In the present study, we determined the underlying mechanisms of TGF-β1-induced TWIST1 expression and its effect on prostate cancer cell invasion. TGF-β1 stimulated STAT3 phosphorylation and HIF-1α expression. Silencing either STAT3 or HIF-1α efficiently attenuated TGF-β1-induced TWIST1 expression. Further ectopic expression of a dominant negative mutant of STAT3 reduced TGF-β1-induced TWIST1 expression. In addition, STAT3 and HIF-1α up-regulated TWIST1 expression by direct binding to a TWIST1 promoter. Strikingly, STAT3 also enhanced TGF-β1-induced TWIST1 expression through HIF-1α stabilization. Collectively, we demonstrate a mechanistic cascade of TGF-β1 up-regulating STAT3 activation and HIF-1α stabilization and subsequent TWIST1 expression, leading to prostate cancer invasion.

Background: Rab25 is a member of the Rab11 subfamily and exclusively expressed in epithelial cells. As a small GTP-binding protein, Rab25 has been known to mediate recycling of proteins from the endosome to the plasma membrane. Cancer metastasis is multi-step events including epithelial-to-mesenchymal transition (EMT). Various transcription factors mediate EMT through downregulation of E-cadherin. In the present study, we investigate whether Rab25 induces EMT transcription factors, thereby increasing cancer invasiveness. Methods: Immunoblotting, quantitative RT-PCR and immunofluorescence assay were used to examine the expression of Rab25 and EMT factors. siRNAs of Rab25 and Snail were transfected to determine their role in Rab25-induced cancer cell EMT and invasiveness. Transwell invasion assay were used to determine cancer cell invasiveness. Results: Ectopic expression of Rab25 marked reduced E-cadherin expression, while Snail expression was upregulated. In addition, Rab25 significantly aggravated cancer cell invasiveness. However, silencing Snail expression by utilizing specific siRNA significantly attenuated cancer cell invasion. In addition, Rab25 induced phosphorylation of Akt and GSK-3beta. However, pharmacological inhibition of Akt and GSK-3beta marked attenuated Rab25-induced Snail expression. Further, we observed that a beta1integrin located upstream of an Akt/GSK-3beta signaling is important for Rab25-induced Snail expression and cancer cell invasion. Conclusion: Our results show for the first time that Snail mediates Rab25-induced cancer cell EMT and invasiveness through a beta1 integrin /Akt/GSK-3beta signaling cascade, providing novel biomarkers, and potential therapeutic targets for deadly cancers. Citation Format: Bo Young Jeong, Kyung Hwa Cho, Seung Hwa Kim, Yu Na Kim, Chang Gyo Park, Hoi Young Lee. Rab25 aggravates cancer cell invasion through Snail expression. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr B36.