A Comparison of Health Risks from PM2.5 and Heavy Metal Exposure in Industrial Complexes in Dangjin and Yeosu·Gwangyang.

Particulate matter (PM) can cause illness, including respiratory diseases, and PM2.5 compositions are likely to vary according to the emission profiles of industrial complexes. This study analyzed and compared the concentrations and distributions of PM2.5 and heavy metals in two regions of Republic of Korea: Yeosu·Gwangyang, which houses a massive national industrial complex, and Dangjin, which houses power plants. Further, we conducted a health risk assessment on the residents of the areas near these industrial complexes. Measurements were taken at five different points in each setting over a two-year period from August 2020 to August 2022. We found differences in PM2.5 concentrations and heavy metal composition ratios across the sites. Specifically, PM2.5 concentrations exceeded the standard of 1 at all measurement sites, while the specific heavy metals exceeding the standard varied across the sites. Ultimately, we observed regional differences in PM2.5 composition across measurement sites across and within the two regions and variations in health risks and according health effects due to the absence of PM2.5 toxicity values, and compared the health risks of two industrial complexes with different characteristics. These findings underscore the importance of considering not only PM2.5 but also its composition in exposure and health risk assessments.

Comparative Study on the Outcome of Trauma Patients Transferred by Doctor Helicopters and Ground Ambulance in South Korea.

OBJECTIVE: The purpose of this study was to analyze the cost-effectiveness of helicopter emergency medical services (HEMS) for its economic operations in South Korea. METHODS: This study targeted trauma patients that were transported by either HEMS or ground emergency medical services (GEMS) from the scene of an accident to a regional emergency medical center. From this patient population, severe trauma patients (injury severity score ISS ≥ 16 points) with a distance travelled from the scene of the injury to the hospital that was 30 km or longer and with analyzable outcome data were extracted and included in this study. Cost-effectiveness was analyzed from survival and efficiency based on medical costs incurred from the pre-hospital setting to hospital discharge. This study included a total of 34 HEMS and 105 GEMS patients with an Injury Severity Score (ISS) ≥ 16 points from a pool of 357 potential patients. RESULTS: The survival-to-discharge rate of HEMS was 29 of 34 patients (85.3%) and was significantly higher than that of GEMS, where only 66 of 105 patients (62.8%) survived to discharge (P = 0.024). The expected and the actual mortality was higher in HEMS than it was in GEMS. Statistical significant difference in cost was found between the 2 groups (P = 0.002). CONCLUSIONS: The results of the present study indicate the increased discharge rate, survival rate and reduced in hospital mortality of HEMS with reduced admission time. This result association leads to reasonable cost effectiveness and efficient estimates overall.

Coarsening behavior of bulk nanobubbles in water.

In recent years, minuscule gas bubbles called bulk nanobubbles (BNBs) have drawn increasing attention due to their unique properties and broad applicability in various technological fields, such as biomedical engineering, water treatment, and nanomaterials. However, questions remain regarding the stability and behavior of BNBs. In the present work, BNBs were generated in water using a gas-liquid mixing method. NB analysis was performed using a nanoparticle tracking analysis (NTA) method to investigate the coarsening behavior of BNBs in water over time. The diameters of the BNBs increased, and their cubic radii increased linearly (r3 ~ t) over time. While the concentration of BNBs decreased, the total volume of BNBs remained the same. The size distribution of the BNBs broadened, and the concentration of larger BNBs increased over time. These results indicate that relatively small BNBs disappeared due to dissolution and larger BNBs grew through mass transfer between BNBs instead of coalescence. In other words, BNBs underwent Ostwald ripening: gas molecules from smaller BNBs diffused through the continuous phase to be absorbed into larger BNBs.

Comparative Study on the Outcome of Stroke Patients Transferred by Doctor Helicopters and Ground Ambulances in South Korea: A Retrospective Controlled Study.

The purpose of this study was to analyze the effectiveness of helicopter emergency medical services (HEMS) for its economic operations in South Korea. This study targeted stroke patients who were transported via HEMS or ground emergency medical services (GEMS) from the scene of an accident to a regional emergency medical center. From this patient population, stroke patients who traveled at least 50 km from the scene of the cerebral infarction to the hospital with analyzable outcome data were extracted and included in this study. This study included 26 HEMS and 102 GEMS stroke patients from a pool of 183 potential patients. The survival-to-discharge rate of patients transported via HEMS (96.2%; 25/26) was significantly higher than that of patients transported via GEMS (83.2%; 104/128) (P=0.001). The HEMS transfer was quicker with respect to the decision-making process because the emergency physician actively evaluates and communicates on-site and during in-transit travel to request an appointment immediately upon arrival at the emergency room. These results indicate that using HEMS increased discharge and survival rates and reduced in-hospital mortality of HEMS of stroke patients with a reduced admission time. This result association leads to reasonable cost-effectiveness and efficient estimates overall. In conclusion, HEMS indicate reduced time taken for stroke patients to be hospitalized and treated and decreased mortality after 24 hours. According to this result, HEMS transport can be more effective than GEMS in long-distance delivery of stroke patients.

Effect of dissolved-gas concentration on bulk nanobubbles generation using ultrasonication.

In this study, the effects of dissolved-gas concentration in liquid water on the nucleation and growth of bubbles and nanobubble (NB) generation were investigated by measuring the concentration and size distribution of NBs. Three types of liquids with different dissolved-gas concentrations-undersaturated, saturated, and supersaturated deionized (DI) water-were prepared, and NBs were generated via ultrasonic irradiation. As the dissolved-gas concentration increased, a large number of bubbles with relatively large diameters (several tens of micrometers or more) were generated, but the NB concentration decreased. The surface tension decreased with an increase in the dissolved gas concentration, and thus, the tensile strength which required for bubble growth became lower. Therefore, there were barely any NBs in supersaturated conditions because of the accelerated nucleation and bubble growth.

Assessment of the disaster medical response system through an investigation of a 43-vehicle mass collision on Jung-ang expressway.

PURPOSE: It was considered the challenges of the actual response and the potential for improvement, including the activities of the disaster response system, national emergency medical center, and the regional base hospital for the treatment of multiple traffic accident victims. The purpose of this study was to analyze the accident management system through real investigating the multiple collision over 10 vehicles with mass casualty events as a disaster situation. METHODS: This study was retrospective study to analyze the disaster event with multiple collision traffic accident on the expressway in Korea. We visited five medical centers for eight days since the accident occurred and interviewed the injured patients in this accident to examine the health status and medical records. After that, we visited the sixteen car-repair shops in four cities for real investigate about damaged vehicles. According to the arrangement of the accident situation for the accident vehicles through real-world investigation, we reproduced all parts of the accident scene, which were real-world investigated, by the accident situation sketch program. The collected data were summarized by Collision Deformation Classification (CDC) codes, and the medical records of the occupants were assessed using the Injury Severity Score (ISS). RESULTS: The cause of the accident was snow freezing of the road. The information about 72 injured patients on 31 damaged vehicles was collected by phone, visit, and actual accident investigation. Of the 72 patients who were examined, 4 were severely injured and 68 were mildly injured. The accident occurred in the order of Sedan 13 (41.9%), SUV 11 (35.5%), Truck 4 (12.9%), Van 2 (6.5%) and Bus 1 (3.2%). The median value of the age [lower quartile and upper quartile] was 43 [34.5-52] years old and the patients included 25 drivers, 11 passengers, 7 back seat passengers, and 29 bus passengers. CONCLUSION: The primary cause of this mass collision accident was road surface freezing, but the more serious secondary cause was a driver's inability to avoid the accident scene after the first collision. The severely injured occupants were occurred on the roads outside and inside the vehicle. In the event of a disaster, various teams from the police team, firefighting team, DMAT, EMS, road management team are gathered, and communication and command system between each team is important in order to identify and solve the disaster situation. To do this, it is important to develop manuals and prepare for training through repeated simulations.

Indoor contamination from pesticides used for outdoor insect control.

The present study assessed the indoor level of pesticide residue contamination at a total of 45 dwelling facilities in 5 cities of South Korea from June to November 2014. Pesticide residue contamination was assessed by measuring the frequency and concentration of chlorpyrifos, dichlorvos, and cypermethrin residues in airborne particles, indoor dust, and surface wipes. A preparatory test showed a decreasing tendency in the concentrations of pesticide residues in indoor air over time: from 0.458 to 0.073mg/m3 in dichlorvos for 4weeks and from below 0.050mg/m3 to non-detection in the other substances for 2weeks. Then, pesticide residues were detected indoors 4weeks after outdoor chemical control, implying the infiltration of pesticide particles from outdoors. Airborne particles of dichlorvos were found at a higher level (74.4% of samples at a concentration of 0.053mg/m3), whereas those of the other substances were detected at lower levels (6.1% at 0.002mg/m3 in chlorpyrifos and 9.4% at 0.022mg/m3 in cypermethrin). There was no consistent tendency in the indoor levels of pesticide residue contamination according to dwelling types or indoor height. The indoor levels of dichlorvos residue contamination were lower in industrial districts than in urban or rural districts: 63.9% and 0.013mg/m3 for airborne particles, 13.3% and 0.002µg/g for indoor dust, and 6.7% and 0.001mg/cm2 for surface wipes, respectively. There were no significant differences in the indoor levels of pesticide residue contamination between urban and rural districts. The current study found that most dwelling facilities managed their indoor levels of pesticide residue contamination below permissible exposure limit (PEL, 1.0mg/m3) or threshold limit value (TVL, 0.1mg/m3), whereas some facilities did not. So, we suggest that certain guidelines should be drawn up regarding the indoor environment management.

Emergency medical service systems in Sri Lanka: problems of the past, challenges of the future.

INTRODUCTION: The concept of emergency medical services (EMS) is new to Sri Lanka. This article describes the development, delivery, and future ideas for EMS in Sri Lanka. Sri Lanka also faces frequent natural hazards that justify the establishment of an EMS service. METHODOLOGY: Data and information regarding emergency medical care in Sri Lanka were collected and reviewed from resources including websites and research papers. RESULTS: Currently, there are no qualified emergency medical physicians in Sri Lanka. However, a specialist training program for emergency physicians was initiated in 2012. There is no formal system to train emergency medical technicians (EMTs). Sri Lankans usually use taxies or their private vehicles to get to the hospital in the case of an emergency. All of the hospitals have ambulances that they can use to transport patients between hospitals. Most hospitals have emergency treatment units. Those at larger hospitals tend to be better than those at smaller hospitals. Although there is a disaster management system, it is not focused on emergency medical needs. DISCUSSION: Many aspects of the EMS system in Sri Lanka need improvement. To start, the emergency telephone number should cover the entire country. Training programs for EMTs should be conducted regularly. In addition, ambulances should be allocated for prehospital care. In the process of these developmental changes, public awareness programs are essential to improve the function of the EMS system. CONCLUSION: Despite many current shortcomings, Sri Lanka is capable of developing a successful EMS system.

Management of Clevudine-Resistant Chronic Hepatitis B: A Multicenter Cohort Study.

BACKGROUND/AIMS: Data are lacking regarding the management of chronic hepatitis B (CHB) with resistance to clevudine (CLV). This study evaluated the efficacy of different rescue therapies for CLV-resistant CHB. METHODS: Patients with CLV-resistant CHB were enrolled in the cohort, and all patients developed virologic breakthrough during CLV therapy and had confirmed-genotypic resistance to CLV (rtM204I mutation) before enrollment. RESULTS: Of the 107 patients, 12 received adefovir (ADV), 21 received a CLV plus ADV combination (CLV+ADV), 34 received a lamivudine plus ADV combination (LAM+ADV), and 40 received entecavir (ETV) therapy for 48 weeks. The CLV+ADV group had the lowest hepatitis B virus (HBV) DNA level (p<0.0001) and showed the greatest reduction of HBV DNA levels from baseline compared to all other groups (p=0.004) at week 48. HBV DNA was undetectable (<70 IU/mL) in 0%, 57.1%, 21.2%, and 27.5% (p=0.003) of the patients in each group, respectively, at week 48. At the end of the study, the mean alanine transaminase (ALT) level, rate of ALT normalization, and rate of hepatitis B envelope antigen loss or seroconversion did not differ between groups. CONCLUSIONS: CLV+ADV combination therapy in patients with CLV-resistant CHB more effectively suppresses HBV replication than ETV, ADV, or LAM+ADV therapy.

Evaluation of an International Disaster Relief Team After Participation in an ASEAN Regional Forum Disaster Relief Exercise.

OBJECTIVE: Devastating disasters around the world directly contribute to significant increases in human mortality and economic costs. The objective of this study was to examine the current state of the Korea Disaster Relief Team that participated in an international training module. METHODS: The whole training period was videotaped in order to observe and evaluate the respondents. The survey was carried out after completion of the 3-day training, and the scores were reported by use of a 5-point Likert scale. RESULTS: A total of 43 respondents were interviewed for the survey, and the results showed that the overall preparedness score for international disasters was 3.4±1.6 (mean±SD). The awareness of the Incident Command System for international disasters was shown to be low (3.5±1.1). Higher scores were given to personnel who took on leadership roles in the team and who answered "I knew my duty" (4.4±0.6) in the survey, as well as to the training participants who answered "I clearly knew my duty" (4.5±0.5). CONCLUSION: The preparedness level of the Korea Disaster Relief Team was shown to be insufficient, whereas understanding of the roles of leaders and training participants in the rescue team was found to be high. It is assumed that the preparedness level for disaster relief must be improved through continued training. (Disaster Med Public Health Preparedness. 2016;1-5).

Effects of Eucommia ulmoides extract on longitudinal bone growth rate in adolescent female rats.

Eucommia ulmoides is one of the popular tonic herbs for the treatment of low back pain and bone fracture and is used in Korean medicine to reinforce muscles and bones. This study was performed to investigate the effects of E. ulmoides extract on longitudinal bone growth rate, growth plate height, and the expressions of bone morphogenetic protein 2 (BMP-2) and insulin-like growth factor 1 (IGF-1) in adolescent female rats. In two groups, we administered a twice-daily dosage of E. ulmoides extract (at 30 and 100 mg/kg, respectively) per os over 4 days, and in a control group, we administered vehicle only under the same conditions. Longitudinal bone growth rate in newly synthesized bone was observed using tetracycline labeling. Chondrocyte proliferation in the growth plate was observed using cresyl violet dye. In addition, we analyzed the expressions of BMP-2 and IGF-1 using immunohistochemistry. Eucommia ulmoides extract significantly increased longitudinal bone growth rate and growth plate height in adolescent female rats. In the immunohistochemical study, E. ulmoides markedly increased BMP-2 and IGF-1 expressions in the proliferative and hypertrophic zones. In conclusion, E. ulmoides increased longitudinal bone growth rate by promoting chondrogenesis in the growth plate and the levels of BMP-2 and IGF-1. Eucommia ulmoides could be helpful for increasing bone growth in children who have growth retardation.

A table-shaped tactile sensor for detecting triaxial force on the basis of strain distribution.

A slim and flexible tactile sensor applicable to the interaction of human and intelligent robots is presented. In particular, a simple sensing principle for decoupling of three-dimensional force is proposed. Sensitivity of the proposed tactile sensor is tested experimentally. To improve the sensitivity of the sensor, a table-shaped sensing element was designed. Table-shaped structure can convert an external acting force into concentrated internal stress. A "triaxial force decoupling algorithm" was developed by combining two-dimensional mapping data calculated by finite element analysis. The sensor was calibrated under normal and tangential forces. The external loads applied to the sensor could be decoupled independently as a function of the strain-gauge responses.

Phenotypic, physiological, and molecular evaluation of rice chilling stress response at the vegetative stage.

Rice is a chilling-sensitive plant that is particularly prone to injury during the early stages of seedling development and during flowering. Significant variation exists between subspecies with japonica cultivars generally being less sensitive than most indica cultivars. In most temperate and subtropical countries where rice is grown, crop damage often occurs during the early stages of seedling development due to occasional cold snaps coinciding with the first few weeks after direct seeding in late spring to early summer. Irreversible injuries often result in seedling mortality or if the crop survives a stress episode, plant vigor and resistance to pests and diseases are severely compromised. Recent physiological and molecular studies have shown that oxidative stress is the primary cause of early chilling injuries in rice and the differential responses of indica and japonica cultivars are defined to a large extent by gene expression related to oxidative signaling and defenses. In this chapter, we summarize basic phenotypic, physiological, and molecular procedures that can be adopted for routine evaluation of differential responses between cultivars as well as for functional genomics studies.

Treatment of lamivudine-resistant chronic hepatitis B infection: a multicenter retrospective study.

OBJECTIVES: To compare the efficacy of rescue therapies in lamivudine (LAM)-resistant chronic hepatitis B (CHB) infections including: (1) adefovir dipivoxil (ADV) monotherapy, (2) ADV plus LAM combination therapy and (3) entecavir (ETV) 1.0 mg monotherapy. MATERIALS AND METHODS: The authors designed a multicenter-retrospective study. Eight institutions participated in the study from Korea. RESULTS: A total of 343 LAM-resistant CHB patients were enrolled. The proportion of patients with undetectable serum hepatitis B virus (HBV) DNA levels at month 24 after the initiation of rescue therapy was higher in the ADV plus LAM combination therapy group (39/64, 60.9%) than in the ADV monotherapy (50/126, 39.7%) and ETV 1.0 mg monotherapy (19/48, 39.6%) groups (p = 0.014). Mean serum HBV DNA levels at 24 months were 2.07 ± 1.21 log(10) IU/ml in the ADV plus LAM combination therapy group, 2.74 ± 1.74 log(10) IU/ml in the ADV monotherapy group and 3.08 ± 1.97 log(10) IU/ml in the ETV 1.0 mg monotherapy group (p = 0.014). In multivariate analysis, a finding of undetectable serum HBV DNA level at 6 months and ADV plus LAM combination therapy (vs. ADV) was an independent factor for predicting undetectable serum HBV DNA at month 24 (odds ratio, 1.003; 95% confidence interval, 1.000-1.006; p = 0.026). CONCLUSIONS: ADV plus LAM combination therapy is more effective in reducing viral load than switching to ADV or ETV 1.0 mg in patients with LAM-resistant CHB.

Acute comitant esotropia in a child with a cerebellar tumor.

We report a case of acute comitant esotropia in a child with a cerebellar tumor. A 3-year-old boy was referred for management of a 9 month history of acute acquired comitant esotropia. On first presentation, the patient's angle of esodeviation was 50 prism-diopters (PD) at distance and near fixation without any lateral incomitance. The cycloplegic refraction revealed +0.75 diopters in both eyes. Very mild bilateral papilledema was found on the fundus examination, but the neurological examination did not reveal any other pathological findings. Brain MRI showed a 5 cm mass located in the midline of the cerebellum as well as hydrocephalus. The mass was completely excised and histological examination confirmed the diagnosis of pilocytic astrocytoma. Despite neurosurgery, the patient's strabismus remained unresolved. One year after neurosurgery, both medial rectus muscles were surgically recessed by 6 mm, resulting in esotropia of 8PD at distant and near fixation without restoration of bifoveal fusion at follow-up 2 years after the eye muscle surgery. Therefore, acute onset comitant esotropia in a child can be the first sign of a cerebellar tumor, even without any other neurological signs and symptoms.