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Previous studies reported the impact of intrinsic and extrinsic factors on intraoperative hypothermia. However, no clinical study to date has considered the effects of both the phase of the menstrual cycle (an intrinsic factor) and the fresh gas flow rate (FGF) during anesthesia (an extrinsic factor) on the core body temperature and intraoperative hypothermia. This study is aimed at investigatig the effect of the menstrual cycle phase on intraoperative hypothermia when considering the FGF in patients who underwent laparoscopic gynecologic surgery. This study included 667 women aged 19-65 years with menstruation cycles and menopause. The patients were divided into the follicular, luteal, and menopause groups. The primary outcome was the correlations of hormonal status with intraoperative hypothermia. Secondary outcomes included the incidence of intraoperative hypothermia, time to onset of hypothermia, incidence of shivering after anesthesia, and frequency of antishivering drug use in the three groups and risk factors for hypothermia. Overall, the hypothermia incidence was the lowest and the time to onset of hypothermia was the longest in the luteal phase group. At a high FGF, the incidence of hypothermia in the luteal phase group was lower than that in the other two groups ( P < 0.05 ). At a low FGF, the time to onset of hypothermia in the luteal phase group was longer than that in the other two groups ( P < 0.05 ). The female hormonal status had weak positive correlations with hypothermia at low and high FGF rates. A high FGF in univariate and multivariate analyses, follicular phase and menopause in multivariate analysis, and estradiol and progesterone levels in univariate analysis were risk factors for hypothermia. When considering the FGF, the luteal phase is associated with better outcomes concerning intraoperative hypothermia.

The natural attenuation potential of a vadose zone against diesel is critical for optimizing remedial actions and determining groundwater vulnerability to contamination. Here, diesel attenuation in unsaturated soils was systematically examined to develop a qualitative relationship between physical soil properties and the natural attenuation capacity of a vadose zone against diesel. The uniformity coefficient (C

The failure of Medium Voltage (MV) induction motors is a major concern in the steel industry since it can cause an unplanned outage resulting in significant economic consequences. Predictive maintenance based on offline and online testing of the induction motors is critical for maintaining reliable, efficient, and safe plant operations. Many years of experience has indicated that the MV induction motor failure rate can be reduced with periodic motor testing, resulting in improved plant reliability and productivity. It has been observed that false fault indications are commonly produced by commercially available test equipment. Considering that the application of multiple types of tests can improve outcome reliability, the effectiveness of a new test approach based on the analysis of the motor starting current was investigated for detecting defects in the rotor cage and reactor starting. An analysis of the starting data obtained from 614-MV induction motors operating at a steel mill over the past 10+ years showed that these two types of faults were present in 45-MV motors. Five successful case studies of rotor cage and four cases of reactor starting defects are presented in this article to demonstrate the advantages of starting current analysis for induction motor monitoring.

Biogeochemical reactions take place when reactants are present at the same location and time, which occurs through pore-scale mixing. Although the degree of mixing should be variable in space and time, most conventional reactive transport models do not consider mixing-dependent reaction rates and often make predictions based on rates measured with batch experiments. We quantify the effect of pore-scale mixing on the biodegradation rate of dissolved organic carbon (DOC) with sediment batch experiments, and study its potential impact on the field-scale fate and transport of DOC with numerical simulations. We collected sediment samples from an aquifer storage transfer and recovery (ASTR) field site located in Busan, South Korea, and conducted batch experiments to measure mixing-dependent biodegradation rates. Complete mixing conditions were realized by continuously shaking the batch, and diffusion-limited mixing conditions were realized by keeping the batch under static conditions. The two mixing conditions are most widely used conditions in batch experiments and they also represent the maximum and minimum degree of mixing. The different mixing conditions led to significant differences in the biodegradation rates (a factor of 4.9 on average). We then performed reactive transport modeling using the measured biodegradation rates to study the potential impact of pore-scale incomplete mixing on the field-scale DOC biodegradation. The results show that pore-scale mixing can significantly affect the effectiveness of biodegradation at the ASTR site. We generalize this finding by performing a comprehensive nondimensional sensitivity analysis of the fate and transport of DOC to pore-scale mixing conditions over a wide range of P e ´ clet and Damkohler numbers. We show that pore-scale incomplete mixing can be a major source of uncertainty in field-scale model predictions.

Various hydrogeochemical processes can modify the quality of river water during riverbank filtration (RBF). Identifying the subsurface processes responsible for the bank-filtered water quality is challenging, but essential for predicting water quality changes and determining the necessity of post-treatment. However, no systematic approach for this has been proposed yet. In this study, the subsurface hydrogeochemical processes that caused the high concentrations of total iron (Fe) and sulfate (SO42−) in the bank-filtered water were investigated at a pilot-scale RBF site in South Korea. For this purpose, water quality variations were monitored in both the extraction well and the adjacent river over five months. The volumetric mixing ratio between the river water and the native groundwater in the RBF well was calculated to understand the effect of mixing on the quality of water from the well and to assess the potential contribution of subsurface reactions to water quality changes. To identify the subsurface processes responsible for the evolution of Fe and SO42− during RBF, an inverse modeling based on the chemical mass balance was conducted using the water quality data and the calculated volumetric mixing ratio. The modeling results suggest that pyrite oxidation by abundant O2 present in an unsaturated zone could be a primary process explaining the evolution of total Fe and SO42− during RBF at the study site. The presence of pyrite in the aquifer was indirectly supported by iron sulfate hydroxide (Fe(SO4)(OH)) detected in oxidized aquifer sediments.

Identifying the cause of inconsistent landfarming efficacy is critical to designing optimal remedial strategies for petroleum-contaminated sites. We assessed contaminated soils collected from two former military bases in South Korea to better understand the role and influence of different factors. Landfarming remediation was simulated in the laboratory by applying comparable practices (such as tillage and bioaugmentation) and the relevant mechanism was examined. We then systematically examined potential factors affecting petroleum-removal efficacy, including the content of fine soil particles, the initial concentration and composition of petroleum contaminants, and the degree of soil-contaminant interaction. The distribution range of total petroleum hydrocarbons (TPHs) and the size of unresolved complex mixture (UCM) found in gas chromatography data showed that petroleum composed of TPHs with lower carbon numbers and having smaller size of UCM could be treated more effectively by landfarming. Incorporating the evaluation of the distribution range and UCM properties of petroleum, rather than simply considering its total concentration, is a more accurate and efficient method for determining the site-specific suitability of landfarming as a remedial option, as well as for assessing the necessity of supplementary processes.

Riverbank filtration is a commonly-used technology that improves water quality by passing river water through aquifers. In this study, a riverbank filtration site in Busan, South Korea, was investigated to understand the spatiotemporal evolution of high iron and sulfate concentrations observed in the riverbank-filtered water. Discrepancies between the nonreactive transport results and field measurements suggest that iron-sulfate-related geochemical reactions play a major role in the spatiotemporal evolution of the hydrochemical properties. Pyrite oxidation was hypothesized to be the main process driving the release of iron and sulfate. To test this hypothesis, a reactive transport model was developed, that implemented pyrite oxidation as a kinetic process and subsequent ferrous iron oxidation and ferric iron precipitation as equilibrium processes. The model accurately captured the temporal evolution of sulfate; however, iron concentrations were underestimated. Sensitivity tests revealed that adjusting reaction constants significantly improved the prediction of iron concentrations. The results of this study suggest that pyrite oxidation can affect the hydrochemistry of riverbank-filtered water and highlight the potential limitations of using theoretical reaction constants in field modeling applications.

INTRODUCTION AND OBJECTIVE:To identify whether the concurrent systematic biopsy (SB) is still necessary in the magnetic resonance imaging fusion-targeted biopsy (MRIFTB) eraMETHODS:Total of 714 men...