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PURPOSE: To examine the diagnostic performance for the longitudinal extent of extrahepatic bile duct (EHD) cancer on computed tomography (CT) after biliary drainage (BD) and investigate the appropriate timing of magnetic resonance imaging (MRI) acquisition. METHODS: This retrospective study included patients who underwent curative-intent surgery for EHD cancer and CT pre- and post-BD between November 2005 and June 2021. The biliary segment-wise longitudinal tumor extent was evaluated according to the 2019 Korean Society of Abdominal Radiology consensus recommendations, with pre-BD CT, post-BD CT, and both pre- and post-BD CT. The performance for tumor detectability was compared using generalized estimating equation (GEE) method. When preoperative MRI was performed, patients were divided into two subgroups according to the timing of MRI with respect to BD, and the performance of MRI obtained pre- and post-BD was compared. RESULTS: In 105 patients (mean age: 67 ± 8 years; 74 men and 31 women), the performance for tumor detectability was superior using both CT scans compared with using post-BD CT alone (reader 1: sensitivity, 72.6% vs. 64.6%, P < 0.001; specificity, 96.9% vs. 94.8%, P = 0.063; reader 2: sensitivity, 77.2% vs. 72.9%, P = 0.126; specificity, 97.5% vs. 94.2%, P = 0.003), and it was comparable with using pre-BD CT alone. In biliary segments with a catheter, higher sensitivity and specificity were observed using both CT scans than using post-BD CT (reader 1: sensitivity, 74.4% vs. 67.5%, P = 0.006; specificity, 92.4% vs. 88.0%, P = 0.068; reader 2: sensitivity, 80.5% vs. 74.4%, P = 0.013; specificity, 94.3% vs. 88.0%, P = 0.016). Post-BD MRI (n = 30) exhibited a comparable performance to pre-BD MRI (n = 55) (reader 1: sensitivity, 77.9% vs. 75.0%, P = 0.605; specificity, 97.2% vs. 94.9%, P = 0.256; reader 2: sensitivity, 73.2% vs. 72.6%, P = 0.926; specificity, 98.4% vs. 94.9%, P = 0.068). CONCLUSION: Pre-BD CT provided better diagnostic performance in the preoperative evaluation of EHD cancer. The longitudinal tumor extent could be accurately assessed with post-BD MRI, which was similar to pre-BD MRI. CLINICAL SIGNIFICANCE: The acquisition of pre-BD CT could be beneficial for the preoperative evaluation of EHD cancer when BD is planned. Post-BD MRI would not be significantly affected by BD in terms of the diagnostic performance of the longitudinal tumor extent.

Background : Pre-diabetes can develop into type 2 diabetes mellitus, but can prevented by regular exercise. However, the outcomes when combining unsupervised Kinect-based mixed-reality (KMR) exercise with continuous glucose monitoring (CGM) remain unclear. Therefore, this single-arm pilot trial examined changes in blood glucose (BG) concentrations over 672 hours (4 weeks), including a 2-week period of KMR exercise and CGM in individuals with pre-diabetes. Methods : This was a pre-and post-treatment case-control study with nine participants. General questionnaires were administered and body composition, fasting BG concentrations, and 2-hour oral glucose tolerance test (2-OGTT) results were measured pre-and post-treatment. Weekly average glucose concentrations, hyperglycemia rate, hypoglycemia rate, average glucose concentration over time, amount of physical activity, amount of food intake, and pre- and postprandial BG (immediately and 30, 60, 90, and 120 minutes after lunch) were measured over 4 weeks (pre-test, exercise, and post -test weeks). Glucose concentrations were measured before exercising, between sets, and 30 and 60 minutes after exercise during the 2 weeks of unsupervised exercise (3 days/week). Results : In all participants, body mass index (27.16±2.92 kg/m2;), fasting BG (108.00±7.19 mg/dL), 2-OGTT (162.56±18.12 mg/dL), hyperglycemia rate (P=0.040), and 90-minute postprandial BG (P=0.035) were significantly reduced during the 2 exercise weeks, and the 2-OGTT result (P=0.044) and diastolic blood pressure (DBP) (P=0.046) were significantly reduced at the post -test as compared with the pre-test. Conclusion : This study found that 2 weeks of unsupervised KMR exercise reduced 2-OGTT, DBP, hyperglycemia rate, and 90-minute postprandial BG concentration. We believed this effect could be identified more clearly in studies involving a larger number of participants and longer durations of exercise.

Background: Recognizing the risk factors and understanding the mechanisms underlying steroid-induced ocular hypertension (SIOH) are vital to prevent potent vision loss and ensure the safety and effectiveness of dexamethasone (DEX) injections. The study aimed to develop a novel nomogram for predicting the risk of SIOH and determining safety zones for steroid injections. Methods: This single-center, retrospective, case-control study included a total of 154 eyes with available measured axial length that had undergone AS-OCT and DEX implantation at the Yonsei University Health System. The eyes were categorized into the SIOH (n = 39) and post-steroid normal IOP (n = 115) groups. We measured intraocular pressure (IOP) for all eyes prior to DEX implantation, at 1 week post-implantation, and at 1, 2, 3, 6, and 12 months thereafter. We used AS-OCT to analyze the trabecular meshwork (TM) height and ocular parameters. Results: The predictive nomogram, including TM height, yielded an AUC of 0.807 (95 % confidence interval [CI], 0.737–0.877) and demonstrated significantly higher predictive accuracy than that of previous nomograms, which did not consider TM height and had an AUC of 0.644 (95 % CI, 0.543–0.745) (p = 0.031). The calibration plot demonstrated a strong predictive accuracy for a predicted value of approximately 0.4. We established cutoff values to ensure different levels of sensitivity and specificity within the safety zone following DEX implantation. Conclusion: Our improved nomogram incorporating TM height as a newly identified risk factor, established a safety threshold for intravitreal DEX implantation, helping identify safe individuals from those who require caution.

Abstract This study aimed to identify the factors causing NH3 emissions in the South Korean Peninsula and West Sea region. To analyze the trends of NH3 and other air pollutants, such as NOx, CO, and NR-PM1, we collected samples from six supersites across the peninsula, a roadside in Seoul, and the West Sea over different sampling periods, ranging from 1 month to 1 year. The highest NH3 concentrations were found at rural areas, ascribed to agricultural activities, particularly NH4NO3 decomposition at high summer temperatures. Areas with low population densities recorded the lowest NH3 concentrations, attributed to the lack of anthropogenic activities. A roadside field experiment confirmed the close link between ambient NH3 and vehicle emissions in urban regions by showing a strong correlation between CO and NOx concentrations and that of NH3. Moreover, we examined oceanic emissions near the eastern coast of South Korea in the West Sea. Long-range transportation studies confirmed that most of the pollutants (NH3, CO, and PM1) were transported by wind from the northeastern region of China. A maritime origin study showed that oceanic emissions and NH4NO3 decomposition in the atmosphere owing to high temperatures were the causing NH3 pollution. These findings provided valuable insights into the emission sources of NH3 in primary air pollutants in South Korea, highlighting the contributions of land-based and oceanic sources. Our study can help inform policymakers and stakeholders for developing effective regional air pollution control strategies.

IntroductionPheochromocytoma is a rare catecholamine-producing neuroendocrine tumor originating from the adrenal medulla chromaffin cells. Hemodynamic instability can occur during the induction of anesthesia and surgical manipulation of the tumor. This study investigated the effects of intraoperative dexmedetomidine administration on hemodynamic stability in patients undergoing laparoscopic adrenalectomy for pheochromocytoma.MethodsForty patients who underwent laparoscopic adrenalectomy for pheochromocytoma were randomly assigned to the dexmedetomidine (n = 20) or control (n = 20) group. The primary outcome of this study was intraoperative hemodynamic stability, and the secondary endpoint was the plasma catecholamine concentrations, specifically of epinephrine and norepinephrine.ResultsThe intraoperative maximum blood pressures were significantly lower in the dexmedetomidine group (control vs. dexmedetomidine group: 182 ± 31 vs. 161 ± 20, 102 ± 17 vs. 90 ± 10, and 128 ± 22 vs. 116 ± 12 [mean ± SD] mmHg and p = 0.020, 0.015, and 0.040 for systolic, diastolic, and mean blood pressure, respectively). The maximum heart rate during surgery was 108 ± 15 bpm in the control group and 95 ± 12 bpm in the dexmedetomidine group (p = 0.010). Other parameters of hemodynamic instability were comparable between both groups. Plasma catecholamine concentrations did not differ between the groups.ConclusionDexmedetomidine infusion following the induction of anesthesia at a rate of 0.5 μg/kg/h significantly attenuated the maximum intraoperative SBP, DBP, MBP, and HR, contributing to improved hemodynamic stability.

Background The endothelial glycocalyx (EG) is an important structure that regulates vascular homeostasis. Deep inferior epigastric perforator (DIEP) flap is expected to cause substantial EG breakdown owing to the long procedural duration and ischemia–reperfusion injury. This prospective, randomized, controlled study aimed to compare syndecan-1 levels during sevoflurane-remifentanil and propofol-remifentanil anesthesia in patients who underwent DIEP flap breast reconstruction. Methods Fifty-one patients were randomized to either sevoflurane (n = 26) or propofol (n = 25) groups. Anesthesia was maintained with remifentanil in combination with either sevoflurane or propofol. The primary endpoint was the concentration of serum syndecan-1 measured at 1 h after surgery. Results Fifty patients (98.0%) completed the study. Patients in the propofol group had significantly lower levels of syndecan-1 than patients in the sevoflurane group at 1 h after operation (23.8 ± 1.6 vs. 30.9 ± 1.7 ng/ml, respectively; Bonferroni corrected P = 0.012). There were no significant differences between groups in postoperative complications. The postoperative hospital stay was 8.4 ± 2.5 days in the sevoflurane group and 7.4 ± 1.0 days in the propofol group (P = 0.077). Conclusions Propofol-remifentanil anesthesia resulted in lesser increases in syndecan-1 levels compared to increases with sevoflurane-remifentanil anesthesia in patients who underwent DIEP flap reconstruction. Our results suggest that propofol-remifentanil anesthesia shows protective effects against EG damage during DIEP flap breast reconstruction in contrast to sevoflurane-remifentanil anesthesia.

Abstract Intraoperative hemodynamics can affect postoperative kidney function. We aimed to investigate the effect of intraoperative mean arterial pressure (MAP) as well as other risk factors on the occurrence of acute kidney injury (AKI) after robot-assisted laparoscopic prostatectomy (RALP). We retrospectively evaluated the medical records of 750 patients who underwent RALP. The average real variability (ARV)-MAP, standard deviation (SD)-MAP, time-weighted average (TWA)-MAP, area under threshold (AUT)-65 mmHg, and area above threshold (AAT)-120 mmHg were calculated using MAPs collected within a 10-s interval. Eighteen (2.4%) patients developed postoperative AKI. There were some univariable associations between TWA-MAP, AUT-65 mmHg, and AKI occurrence; however, multivariable analysis found no association. Alternatively, American Society of Anesthesiologists physical status ≥ III and the low intraoperative urine output were independently associated with AKI occurrence. Moreover, none of the five MAP parameters could predict postoperative AKI, with the area under the receiver operating characteristic curve values for ARV-MAP, SD-MAP, TWA-MAP, AUT-65 mmHg, and AAT-120 mmHg being 0.561 (95% confidence interval [CI], 0.424–0.697), 0.561 (95% CI, 0.417–0.704), 0.584 (95% CI, 0.458–0.709), 0.590 (95% CI, 0.462–0.718), and 0.626 (95% CI, 0.499–0.753), respectively. Therefore, intraoperative MAP changes may not be a determining factor for AKI after RALP.

We performed continuous long-term measurements of PM2.5 mass, comprehensive chemical composition, and optical properties, including scattering and absorption coefficients, from March 2011 to December 2020 at the Metropolitan Air Quality Research Center in Seoul, South Korea. PM2.5 peaked at 38 μg/m3 in 2013 and has been declining steadily since then, reaching 22 μg/m3 in 2020. The extinction coefficients also decreased with the decline in PM2.5, but the correlation between the two factors was not as pronounced. This deviation was mainly attributed to the rapid changes in the chemical composition of PM2.5 over the same period. The mass contribution of sulphate to PM2.5 decreased from 33.9 to 24.1%, but the fraction of nitrate and organic carbon increased from 23.4 and 20.0 to 34.1 and 32.2%, respectively, indicating that sulphate has been replaced by nitrate and organic carbon over the past decade. To assess the effect of changing aerosol chemical compositions on light extinction, we compared the measured extinction coefficients with those estimated via the various existing light extinction approaches, including the revised IMPROVE algorithm. We found that the simplified linear regression model provided the best fit to our data, with a slope of 1.03 and R2 of 0.87, and that all non-linear methods, such as the IMPROVE algorithms, overestimated the observed long-term light extinction by 23 to 48%. This suggests that the simple linear regression scheme may be more appropriate for reflecting the varying aerosol conditions over long periods of time, especially for urban air. However, for conditions where the chemical composition does not change much, non-linear methods such as the IMPROVE scheme are likely to be more appropriate for reproducing light extinction.

Abstract The Observation-Constrained Atmospheric BOX model (OCABOX) was used to analyze the formation of secondary inorganic PM species in the Seoul Metropolitan Area (SMA), South Korea. The measurement data of the ionic components of PM2.5 and their gaseous precursors made at the Olympic Park ground site (37.53°N, 127.12°E) during the Korea-United States Air Quality field campaign were used to run OCABOX in observation-based mode and compare the simulation results. The use of the HNO3 concentrations measured at a marine background site as the boundary conditions appeared to increase the accuracy of the model prediction of HNO3 and particulate NO3− concentrations. For the primary precursors emitted considerably throughout the SMA, such as NOx and NH3, using the data measured inside the SMA as the boundary conditions could lead to more accurate predictions. OCABOX was shown to be a reliable tool to analyze the formation of secondary inorganic aerosol in the SMA if used with appropriate regional background concentrations and observation-based constraints

The endotracheal tube (ETT) with laryngeal adhesive electrodes for intraoperative neural monitoring (IONM) may be related to laryngopharyngeal complications, such as postoperative sore throat (POST), hoarseness, and coughing. We aimed to evaluate the effects of the ETT with laryngeal adhesive electrodes for IONM on the occurrence of laryngopharyngeal complications during thyroidectomy. In this retrospective study, we included 176 patients who underwent thyroidectomy for thyroid cancer between September 2020 and February 2021. The patients were categorized into control (n = 108) and IONM (n = 68) groups. Patients in the IONM group were intubated with the ETT with surface electrodes. Characteristics of the patients and surgery, perioperative variables, and laryngopharyngeal complications, including POST, hoarseness, and cough, were evaluated. The severity and incidence of POST were comparable between the two groups on postoperative days 0, 1, and 2 (p = 0.103, 0.386, and 0.056, respectively). Furthermore, no significant differences were observed in the occurrence of postoperative hoarseness and cough between the groups. The ETT with laryngeal adhesive electrodes for IONM during thyroidectomy did not affect the incidence and severity of postoperative laryngopharyngeal complications, including POST, hoarseness, and cough. Further prospective, double-blinded, randomized clinical trials are required to gain a clearer understanding.

Nipple-areolar complex (NAC)-related complications are common during nipple-sparing mastectomy (NSM), with obesity as a risk factor. Although the incidence of NAC-related complications after robotic NSM (RNSM) with immediate breast reconstruction (IBR) is lower than that after conventional NSM, it remains one of the most unwanted complications. We aimed to evaluate body composition-based risk factors for NAC-related complications after RNSM with IBR. Data of 92 patients with breast cancer who underwent RNSM with IBR using direct-to-implant or tissue expander from November 2017 to September 2020 were analyzed retrospectively. Risk factors for NAC-related complications were identified with a focus on body composition using preoperative transverse computed tomography at the third lumbar vertebra level. Postoperative complications were assessed for 6 months. The most common complication was NAC ischemia, occurring in 15 patients (16%). Multivariate analysis revealed a low skeletal muscle index/total adipose tissue index (SMI/TATI) ratio as an independent NAC ischemia risk factor. An increase in the SMI/TATI ratio by one decreased the incidence of NAC ischemia by 0.940-fold (p = 0.030). A low SMI/TATI ratio is a risk factor for postoperative NAC ischemia in patients undergoing RNSM with IBR for breast cancer. Preoperative body composition-focused evaluation is more valuable than simple body mass index assessment.

Acute myocardial infarction is an acute-stage disease that requires prompt diagnosis and treatment. Primary percutaneous coronary intervention (pPCI) for ST-elevation myocardial infarction (STEMI) is a high-risk factor for post-contrast acute kidney injury (PC-AKI). This retrospective cohort study analyzed the data of 754 patients with STEMI who underwent pPCI and were integrated into the Fast Interrogation Rule for STEMI critical pathway program between 2015 and 2019. We aimed to determine the optimal cutoff baseline eGFR for identifying a high risk of PC-AKI after multivariable adjustment with statistically significant risk factors. We also compared the incidence rates of PC-AKI between the previous and current diagnostic criteria. The probability of PC-AKI increased when the baseline estimated glomerular filtration rate (eGFR) was ≤ 79mL/min/1.73 m2. The optimal cutoff baseline eGFR for high risk of PC-AKI was found to be an eGFR of ≤ 61 mL/min/1.73 m2 after multivariable adjustment. The current diagnostic criteria more accurately identified the patient group with impaired renal function. Our results have clinically significant implications for identifying patients at a high risk of developing PC-AKI, especially before and after the use of contrast agents in patients who require PCI for STEMI in the emergency department.

Abstract Background Interpretation of chest radiographs (CRs) by emergency department (ED) physicians is inferior to that by radiologists. Recent studies have investigated the effect of deep learning-based assistive technology on CR interpretation (DLCR), although its relevance to ED physicians remains unclear. This study aimed to investigate whether DLCR supports CR interpretation and the clinical decision-making of ED physicians. Methods We conducted a prospective interventional study using a web-based performance assessment system. Study participants were recruited through the official notice targeting board for certified emergency physicians and residents working at the present ED. Of the eight ED physicians who volunteered to participate in the study, seven ED physicians were included, while one participant declared withdrawal during performance assessment. Seven physicians’ CR interpretations and clinical decision-making were assessed based on the clinical data from 388 patients, including detecting the target lesion with DLCR. Participant performance was evaluated by area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, and accuracy analyses; decision-making consistency was measured by kappa statistics. ED physicians with

BackgroundA robotic deep inferior epigastric perforator (DIEP) flap created through a totally extraperitoneal approach minimizes violation of the donor site, which may lead to postoperative pain reduction and rapid recovery. The authors compared the clinical outcomes of robotic and conventional DIEP flap breast reconstructions.MethodsData from consecutive patients who underwent mastectomy with DIEP flaps for breast reconstruction between July 2017 and January 2021 were retrospectively reviewed. Patients were divided into robotic and conventional DIEP groups, and the two groups were matched using the inverse probability of treatment weighting method. They were compared based on the reconstruction time, drainage amount, postoperative pain, rescue analgesics, hospital stay, complications, and BREAST-Q scores.ResultsAfter matching, a dataset of 207 patients was formed, including 21 patients in the robotic DIEP group and 186 patients in the conventional DIEP group. The mean reconstruction time was longer in the robotic DIEP group than in the conventional DIEP group (P

Abstract Postural change from a steep Trendelenburg position to a supine position (T-off) during robot-assisted laparoscopic prostatectomy (RALP) induces a considerable abrupt decrease in the mean arterial pressure (MAP). We investigated the variables for predicting postural hypotension induced by T-off using esophageal Doppler monitoring (EDM). One hundred and twenty-five patients undergoing RALP were enrolled. Data on the MAP, heart rate, stroke volume index (SVI), cardiac index, peak velocity, corrected flow time, stroke volume variation, pulse pressure variation, arterial elastance (Ea), and dynamic arterial elastance were collected before T-off and at 1, 3, 5, 7, and 10 min after T-off using EDM. MAP

Abstract This study aimed to compare the effects of volatile anesthesia and total intravenous anesthesia (TIVA) on syndecan-1 shedding in patients with gastric cancer undergoing minimally invasive gastrectomy. Patients were randomly assigned to either the Volatile (n = 68) or the TIVA (n = 68) group. Anesthesia was maintained with sevoflurane/remifentanil or propofol/remifentanil in the Volatile and TIVA groups, respectively. Serum syndecan-1 was evaluated at pre-operation, end of operation, and postoperative day (POD) 1. Inflammatory markers including white blood cell (WBC) count, neutrophil-to-lymphocyte ratio (NLR), and C-reactive protein (CRP), were also measured at pre-operation, end of operation, and POD 1, 2, 3, and 5. The TIVA group showed significantly lower levels of syndecan-1 at the end of the operation compared to the Volatile group; however, no difference was seen between the groups at POD 1. The WBC count and NLR were significantly lower in the TIVA group at the end of the operation than the Volatile group, but there were no differences between the groups at POD 1, 2, 3, and 5. CRP levels were similar between the groups at all time points. In conclusion, despite TIVA being superior to volatile anesthesia in protecting endothelial glycocalyx during the operation, both did not prevent postoperative syndecan-1 shedding after gastrectomy. Clinical trial registration number: NCT04183296 (ClinicalTrial.gov, 03/12/2019).

Red blood cell (RBC) transfusion and albumin administration can affect kidney function. We aimed to evaluate the association between intraoperative 20% albumin administration and acute kidney injury (AKI), along with the duration of hospitalization and 30-day mortality in patients undergoing major abdominal surgery with RBC transfusion. This retrospective study included 2408 patients who received transfusions during major abdominal surgery. Patients were categorized into albumin (n = 842) or no-albumin (n = 1566) groups. We applied inverse probability of treatment weighting (IPTW), propensity score (PS) matching (PSM), and PS covariate adjustment to assess the effect of albumin administration on the outcomes. In the unadjusted cohort, albumin administration was significantly associated with increased risk of AKI, prolonged hospitalization, and higher 30-day mortality. However, there was no significant association between albumin administration and AKI after adjustment (OR 1.26, 95% CI 0.90–1.76 for the IPTW; OR 1.03, 95% CI 0.72–1.48 for the PSM; and OR 1.04, 95% CI 0.76–1.43 for the PS covariate adjustment methods). While albumin exposure remained associated with prolonged hospitalization after adjustment, it did not affect 30-day mortality. Our findings suggest that hyper-oncotic albumin can be safely administered to patients who are at risk of developing AKI due to RBC transfusion.

OBJECTIVES:. Patients with aneurysmal subarachnoid hemorrhage (ruptured brain aneurysm) often have reduced health-related quality of life at follow-up in multiple domains (e.g., cognitive function and social function). We tested the hypothesis that there are distinct patterns of patient outcomes across domains of health-related quality of life, “complex patient outcomes,” in survivors of subarachnoid hemorrhage. DESIGN:. Patients with subarachnoid hemorrhage were prospectively identified. Clinical data were prospectively recorded. Health-related quality of life was prospectively assessed at 3-month follow-up using the National Institutes of Health Patient Reported Outcomes Measurement Information System and neuro-quality of life in the domains of mobility, cognitive function, satisfaction with social roles, and depression. We used k-means clustering to analyze prospectively recorded health-related quality of life data, identifying clusters of complex patient outcomes. Decision tree analysis identified index hospital stay factors predictive of a patient having a particular complex patient outcome at follow-up. SETTING:. Academic medical center. PATIENTS:. One hundred three survivors of subarachnoid hemorrhage. INTERVENTIONS:. None. MEASUREMENTS AND MAIN RESULTS:. We analyzed 103 patients, of whom 75 (72.8%) were female, and mean age was 53.6 ± 13.4 years. There were three complex patient outcomes: health-related quality of life greater than 1 sd better than the U.S. mean across all domains (n = 23, 22.3%), health-related quality of life greater than 1 sd worse than U.S. mean across all domains (n = 26, 25.2%), and satisfaction with social roles greater than 0.5 sd worse than U.S. mean with cognitive function, depression, and mobility scores near the U.S. mean (n = 54, 52.4%). In decision tree analysis, hospital disposition and Hunt and Hess Grade were associated with complex patient outcome. CONCLUSIONS:. Complex patient outcomes across multiple domains of health-related quality of life at follow-up after subarachnoid hemorrhage are distinct and may be predictable.

The model and forecasting performances were evaluated to investigate the effectiveness of bias correction for forecasting PM2.5 concentrations for the period May 2012 to December 2014. Measured concentrations of PM2.5 and major components were obtained from five monitoring stations by region in the Korean Peninsula, and predicted concentrations were obtained from PM2.5 simulations using WRF model v3.4.1 and the CMAQ modeling system v4.7.1. Underestimation was prevalent at all stations for all components except NO3-. The effect of bias correction was pronounced at the Gangwon station, where the difference in PM2.5 between measured and predicted concentrations was largest. The performances for SO42- and the unresolved other component were primarily improved, whereas the performance for NO3-, which was originally overestimated, was degraded. The accuracy of the four-level forecast was moderate at 58% overall, but the probability of detection (POD) of high-concentration events was low at 23%. Bias correction improved the accuracy and POD to 68% and 52%, respectively; however, the rate of false detection of high-concentration events increased as well.

The Korea – United States Air Quality Study (May – June 2016) deployed instrumented aircraft and ground-based measurements to elucidate causes of poor air quality related to high ozone and aerosol concentrations in South Korea. This work synthesizes data pertaining to aerosols (specifically, particulate matter with aerodynamic diameters

This study was conducted for analyzing the contribution factors on ozone concentrations and its long term trends in each major city and province in Korea through several statistical methods such as simple linear regression, generalized linear model, KZ-filer, correlation matrix, Kringing method, and cluster analysis. The overall ozone levels in South Korea have been consistently increasing over the past 10 years. The ozone concentrations in Seoul, the biggest city in Korea, are the lowest in all areas with the highest increasing ratio for 95th% ozone. It is thought that the active photochemical reaction could affect the higher ozone concentration increase. On the other hand, the ozone concentrations in Jeju are the highest in Korea with the highest increasing ratio for 5th%, 33th%, and 50th% ozone. It is also thought that the weak NOx titration could be the reason of higher ozone concentrations in Jeju. In case of Jeju, transport related factors is the major factor affecting the ozone trend. Thus, it is assumed that the variation of ozone trend of Asian region affecting the ozone trend in Jeju, where domestic ozone photochemical reaction is less active than urban area. It is thought that the photochemical reaction plays the role of increasing of ozone concentrations in the urban area, even though the LRT affected on the increase of ozone concentrations in non-urban area.

The dramatic increase in the prevalence of obesity and its accompanying comorbidities are major health concerns in Korea. Obesity is defined as a body mass index ≥25 kg/m2 in Korea. Current estimates are that 32.8% of adults are obese: 36.1% of men and 29.7% of women. The prevalence of being overweight and obese in national surveys is increasing steadily. Early detection and the proper management of obesity are urgently needed. Weight loss of 5% to 10% is the standard goal. In obese patients, control of cardiovascular risk factors deserves the same emphasis as weight-loss therapy. Since obesity is multifactorial, proper care of obesity requires a coordinated multidisciplinary treatment team, as a single intervention is unlikely to modify the incidence or natural history of obesity.

Vitamin D is an essential component of bone and mineral metabolism; its deficiency causes growth retardation and skeletal deformities in children and osteomalacia and osteoporosis in adults. Hypovitaminosis D (vitamin D insufficiency or deficiency) is observed not only in adults but also in infants, children, and adolescents. Previous studies suggest that sufficient serum vitamin D levels should be maintained in order to enhance normal calcification of the growth plate and bone mineralization. Moreover, emerging evidence supports an association between 25-hydroxyvitamin D (25[OH]D) levels and immune function, respiratory diseases, obesity, metabolic syndrome, insulin resistance, infection, allergy, cancers, and cardiovascular diseases in pediatric and adolescent populations. The risk factors for vitamin D insufficiency or deficiency in the pediatric population are season (winter), insufficient time spent outdoors, ethnicity (non-white), older age, more advanced stage of puberty, obesity, low milk consumption, low socioeconomic status, and female gender. It is recommended that all infants, children, and adolescents have a minimum daily intake of 400 IU (10 µg) of vitamin D. Since the vitamin D status of the newborn is highly related to maternal vitamin D levels, optimal vitamin D levels in the mother during pregnancy should be maintained. In conclusion, given the important role of vitamin D in childhood health, more time spent in outdoor activity (for sunlight exposure) and vitamin D supplementation may be necessary for optimal health in infants, children, and adolescents.

This study was conducted for understanding of characteristics of two different high PM episodes occurred during the spring of 2014 in Seoul, Korea. Case 1 was the phenomenon by complex of long range transport and following domestic stagnation. Case 2 was caused by the Asian dust event. During high PM episodes, atmospheric condition became more acidic. The equivalent concentration ratio of nitrate to sulfate decreased to 0.75 and 0.95 in Case 1 and Case 2, respectively, implying that sulfate concentration increase was greater than nitrate concentration increase in high PM episode possibly caused by long range transport. In high PM episodes, SOR and NOR increased with steeper rate for NOR. Considering correlation between temperature and SOR, it was suggested that the homogeneous formation of sulfate was not active in the Korean Peninsula, especially in high PM episodic periods. On the other hand, heterogeneous sulfate formation reaction was dominant for high PM episodes. Considering NOR and its correlation with temperature and humidity, it was suggested that NO2 oxidation was mainly caused by homogeneous oxidation in Case 1. For Case 2, heterogeneous oxidation mainly contributed to forming the nitrate due to the extremely high particle concentrations in Asian dust.

PurposeTo validate the Dinamap ProCare 200 blood pressure (BP) monitor against a mercury sphygmomanometer in children 7 to 18 years old in accordance with the 2010 International Protocol of European Society of Hypertension (ESH-IP2) and the British Hypertension Society (BHS) protocol.MethodsForty-five children were recruited for the study. A validation procedure was performed following the protocol based on the ESH-IP2 and BHS protocols for children and adolescents. Each subject underwent 7 sequential BP measurements alternatively with a mercury sphygmomanometer and the test device by trained nurses. The results were analyzed according to the validation criteria of ESH-IP2.ResultsThe mean (±SD) difference in the absolute BP values between test device and mercury sphygmomanometer readings was 1.85±1.65 mmHg for systolic BP (SBP) and 4.41±3.53 mmHg for diastolic BP (DBP). These results fulfilled the Association for the Advancement of Medical Instrumentation criterion of a mean±SD below 5±8 mmHg for both SBP and DBP. The percentages of test device-observer mercury sphygmomanometer BP differences within 5, 10, and 15 mmHg were 96%, 100%, and 100% for SBP, and 69%, 92%, and 100% for DBP, respectively, in the part 1 analysis; both SBP and DBP passed the part 1 criteria. In the part 2 analysis, SBP passed the criteria but DBP failed.ConclusionAlthough the Dinamap ProCare 200 BP monitor failed an adapted ESH-IP2, SBP passed. When comparing BP readings measured by oscillometers and mercury sphygmomanometers, one has to consider the differences between them, particularly in DBP, because DBP can be underestimated.

Organic carbon (OC) accounts for a large fraction of particulate matter. Since many atmospheric organic compounds have different optical properties, it is difficult to determine the optical properties of OC accurately. In particular, hygroscopicity and light absorption of OC are important factors in understanding the aerosol optical properties. In this study, the sensitivity of organic carbon (OC) to aerosol optical properties was tested. Both the refractive index and the hygroscopicity of OC were considered. Based on the filter-based monthly averaged sampling measurement data from an intensive observation site in Seoul, Korea, the contribution of each component on the aerosol optical properties was estimated. The aerosol optical properties were simulated by combining the aerosol dynamic model for polydispersed aerosols with an optical properties model based on Mie code. The optical properties were compared with the AERONET Aerosol Optical Thickness (AOT) measurement data. In order to estimate the contribution of the light absorption and hygroscopicity of organic carbon (OC) on the optical properties of the aerosols, a sensitivity test was conducted with different imaginary refractive indices and OC hygroscopic growth factors. The results show that mass absorption efficiency can be fitted linearly as the imaginary refractive index increases. This means that one can estimate the mass absorption efficiency of OC as a function of the imaginary refractive index. The results also show that mass extinction and absorption efficiency decrease as the hygroscopic factor of OC increases because of the increase in water content. The contribution of OC to the mass extinction efficiency, however, depends on the chemical composition of other aerosol mixtures and hence, more comprehensive studies are required in this regard.

Objective: The aim of this study was to audit the 22 items and assessed each item's predictive value on surgical outcomes. Background: The KLASS-02 trial revealed that the oncologic outcomes of laparoscopic distal gastrectomy are not inferior to open distal gastrectomy in patients with advanced gastric cancer. The surgeons participating in this trialwere chosen based on the assessment scores from the KLASS-02-QC trial, which used 22 items for standardization of D2 lymphadenectomy and quality control. Methods: We reviewed proficiency scores (PSs) for 22 items for 20 surgeons who participated in KLASS-02. The surgeons were divided into 2 groups according to PS, and the perioperative outcomes of 924 patients enrolled in KLASS-02 were compared between groups. Each item's predictive value for perioperative outcome was then assessed using multivariable regression models. Results: Of the total 924 patients, 529 were operated on by high-score surgeons (high PS) and 395 were operated on by low-score surgeons (low-PS). High-PS group had less intraoperative blood loss, longer operation times, and fewer complications,major complications, reoperations, and shorter first flatus and hospital stay than low-PS group (P=0.006, P<0.001, P<0.001, P<0.001, P=0.042, P=0.013, and P<0.001, respectively). Some items used in KLASS-02-QC predicted perioperative outcomes, such as intraoperative blood loss, major complications, reoperation, and hospital stay. Conclusions: Although this study only analyzed data associated with qualified surgeons, the 22 items effectively assessed the surgeons based on PS. A high score was associated with longer operation times, but better perioperative outcomes. [ABSTRACT FROM AUTHOR]