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Additional file 2:Table S2. Baseline serum pH determinants according to the pH clusters.

Additional file 1:Table S1. Baseline patient characteristics after extreme gradient boosting model with inverse probability treatment weighting-based propensity scores matching.

In national water quality policy, it changed previous regulation method that focuses on concentration of pollutants in effluent water to the way that regulates total amount of pollutants. The target of water quality in watershed of each river was set up, as the government instituted Total Maximum Daily Loads(TMDL). In order to accomplish successfully TMDL, it requires that the amount of pollutant loads discharged from point and nonpoint pollutant source should be investigated. This study, therefore, conducted the monitoring of the stormwater runoff at field region in farming area. And pollutants loads and unit loads discharged from field region results is calculated. As a result, the concentration of pollutants were calculated as follows: 10.5 BOD mg/L, 19.6 CODMn mg/L , 4.5 TN mg/L and 2.4 TP mg/L. The unit load of BOD, CODMn, TOC, TSS, TN and TP discharged from field region, also, were determined to 31.8kg/km/yr, 56.7kg/km/yr, 8.5kg/km/yr, 560.9kg/km/yr, 8.3kg/km/yr and 5.1kg/km/yr, respectively. It was identified that there were some differences of unit loads between the results obtained from this study and previous one. To calculate exact unit loads, therefore, long term monitoring should be conducted.

This work elucidates the effects of pretreatment on primary and secondary sludge using microwave irradiation before the application of elutriated acid fermentation (EAF) systems conducted under different temperature conditions. The EAF used water to elutriate volatile free acids generated in the fermenter which thickened the sludge generated. The results of this study focus on sludge reduction conducted under different temperatures. The SCOD production utilizing a microwave pretreatment method (MW) followed by EAF, with 35°C after the microwave as pretreatment, and from only the EAF at 35 and 55°C was 0.33, 0.11, and 0.22 g SCODprod./g VSfed. Volatile fatty acids (VFAs) production was found to be similar to that of the results of SCOD production. Coliforms and Escherichia coli were not detected after pretreatment with microwave irradiation for time over 5 min.

A laboratory scale bio-reactor equipped with a filter module was examined for the separation of activated sludge, where the effluent was withdrawn by mesh filtration. The synthetic wastewater containing phenol was fed into the reactors, and the removal performance was evaluated under the following conditions: 7 or 14 d of HRT, room temperature (ca. 20°C), synthetic wastewater containing 5,000–20,000 mg/L of phenol, 262 mg/L of NH4-N, 43.7 mg/L of PO4-P, maximum phenol loading rate: 1.43 kg/m3/d, feeding the synthetic wastewater for 5 or 10 h (Run-1) or feeding at once (Run-2), and filtration once a day. The reactors maintained high concentrations of MLSS (10,000–15,000 mg/L), and the filtration was carried out stably in a short time. When the synthetic wastewater containing 5,000 mg/L of phenol was fed into the reactor at 7 d of HRT (0.7 kg/m3/d of phenol loading rate), in the operation of Run-1, the removal rates for phenol, NH4-N, and D-TN were above 99.9, 98, and 96%, respectively. Similar resu...

Many countries including Korea and the USA have carried out many studies on point pollution sources to preserve rivers and lakes over the past 30 years. According to the Ministry of the Environment, Korea, the pollutant loading rate caused by non-point pollutant sources at the major four rivers of Korea comprise of 22–40% of the total pollutant loading rate. The Ministry of the Environment, Korea, predicted that in 2020, non-point pollutant sources should comprise up to 62.5% of the river pollutant loading. For the stable management of non-point pollutant sources, a study of basic data, such as concentration range and run-off pattern of pollutants discharged with land use patterns is very important. This study examined the characteristics of pollutants during rainfall events at the zones for recyclable material separation. The biochemical oxygen demand and chemical oxygen demand (CODcr) concentrations in three rainfall events ranged from 27.4 to 72 mg/L and 66.8 to 168.8 mg/L, respectively. The to...

Combined sewer overflows (CSOs) were examined in an urban catchment with three areas of 11.9, 19.9, and 57.7 ha located in northern Daegu city in Korea. A total of two non-rainfall run-off events were monitored and a variety of water quality parameters were analyzed. During the non-rainfall run-off, most water quality parameters, particularly organic pollutants, were fluctuated accordingly to the discharge of sewage flow. Event mean concentrations (EMCs) during the storm water run-off were shown higher than EMCs of non-rainfall events. The loading rates of overflows against total flow particularly, SS load was 14 times higher. Total CSOs emissions were expected to be around 1.38 to 5.18 kg/ha per event. Few obvious first flush phenomenons were observed due to the inflow of unknown sources and dilution with incessant duration of rainfall.

Total maximum daily load enforced in 2004 is a program to evaluate the amount of pollutants by each land use type and manage to meet a target water quality of each waterbody. The many research to calculate runoff load of pollutants by landuse type have been studied. This study was conducted to calculate pollutants EMC, load and unit load in stormwater runoff generated from tomato growing area. Monitoring was conducted about 32 event during 4years and water quality parameters such as BOD, CODMn, TOC, TSS, TN, TP, NH3-N, NO3-N, PO4-P were analyzed at the laboratory. The average EMC were measured as follows: 9.6 BOD ㎎/L, 17.2 CODMn ㎎/L, 5.5 TOC ㎎/L, 319.4 TSS ㎎/L, 4.4 T-N ㎎/L, 2.6 T-P ㎎/L, 0.5 NH3-N ㎎/L, 0.04 NO2-N ㎎/L, 2.6 NO3-N ㎎/L, 0.8 PO4-P ㎎/L. TN and TP is dichargeed as NO3-N and particle phosphorus type, respectively.