• Korean Journal of Environmental Agriculture
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• v.41 no.3
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• pp.199-205
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• 2022

BACKGROUND: The freezing injury by pruning can be reduced by suspending pruning work when severe cold weather (-23 to -49℃) is forecast. Minimum air temperature of the study area, Gunwi region at February 3, 2012 was -21.9℃, and the subzero temperature continued until April 8, 2012. This study was conducted in two years to investigate the effect of delaying winter pruning until full bloom on shoot growth and fruit quality of 'Fuji'/M.9 apple trees. METHODS AND RESULTS: The time of pruning were March 26 for dormant, April 3 for bud break, and May 2 for full bloom. The winter pruning at full bloom significantly reduced fruit weight for two years compared with the control (winter pruning at dormant), and shoot growth was reduced only in the following year. There was no significant effect of delaying winter pruning at bud break on soluble solid content, fruit red color, return bloom, and pruning weight for two years compared with the control. CONCLUSION(S): These results indicated the delaying winter pruning at bud break of 'Fuji'/M.9 apple tree did not offer any disadvantage over comparable dormant pruning, since the fruit quality was not affected. The delayed pruning at full bloom resulted in decreased fruit weight, though shoot growth, fruit quality, and return bloom were not affected by the delayed pruning. So, the delayed pruning should be considered carefully only for the fruit tree orchards in diseases.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.3
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• pp.251-261
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• 2022

Tuna purse seine fishery (TPF) constitute more than 60% of distant water fishery production in Korea based on a statistic of 2018, and 28 ships from four different companies were under operation at the western and central Pacific Ocean. On this research, common risk factors during TPF were investigated via enumeration of five years Korean fisherman's insurance payment statement, followed by some counterplans to diminish the accident rate. The accident rate of TPF on the Pacific Ocean peaked by 43.0% in 2014 and constantly decreased to 23.0% until 2018, presenting an average of 33.6%. Meanwhile, the accident rate on the Indian Ocean reached the highest point 55.1% in 2014 and declined to 11.6% in 2016, having an average of 24.7%. The average accident rate of the Indian Ocean scored 8.9% lower than the rate of the Pacific Ocean, but no statistic significance was observed. Depending on the process of operation, 'casting or hauling of net' was the most frequent part that people received an injury (40.4%). When the accidents were classified by their types, 'falling down' was the most recurrent cause of the injuries (28.5%). At the point of severity, the worst injuries were induced by crush hazard. Considering aforementioned accident frequency and severity, all the factors on the accident type list were divided into three different groups including high risk, moderate risk, and common risk. This study is expected to contribute to the reduction of occupational accidents during the work of fishermen and establishment of a safety management system for distance water fishing vessels.

• Physical Therapy Korea
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• v.30 no.1
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• pp.15-22
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• 2023

Background: Delivery workers repeatedly get in and out of trucks and walk or run to deliver packages during work. Iliotibial band syndrome (ITBS) is a well-known non-traumatic overuse injury of the lateral side of the knee caused by frequent knee flexion and extension. Hip muscle strength is among the factors that prevent lower extremity injuries. Although many studies have examined the relationship between ITBS and hip muscle strengths, there was no study comparing hip muscle strength and ratio between delivery workers with and without ITBS. Objects: This study aimed to compare hip muscle strength and hip internal/external rotator and adductor/abductor strength ratios between delivery workers with and without ITBS. Methods: Fourteen delivery workers with ITBS matched inclusion criteria in the present study among 20 participants. Because total sample size was required 28 subjects by G*power program (ver. 3.1.9.4; University of Trier), 14 delivery workers without ITBS were recruited. Hip muscle strengths were measured in a side-lying position using a Smart KEMA pulling sensor (KOREATECH Co. Ltd.). An independent t-test was used to compare hip muscle strengths and hip internal/external rotator and hip adductor/abductor strength ratios between delivery workers with and without ITBS. Results: The adductor/abductor strength ratio was significantly greater in delivery workers without ITBS than in those with ITBS (p < 0.05). The strengths of the hip abductor, hip adductor, hip internal rotator, hip external rotator, and the ratio of internal/external rotator strengths were not significantly different between the delivery workers with and without ITBS (p > 0.05). Conclusion: This study's findings showed that delivery workers with ITBS had significantly lesser adductor/abductor strength ratio, while the strengths of the hip abductor and adductor muscles did not differ significantly. These results suggest that adductor/abductor strength ratio should be considered when evaluating and treating ITBS in delivery workers.

• Safety and Health at Work
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• v.14 no.1
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• pp.118-123
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• 2023

Background: Chronic exposure to silica is related with the provocation of an inflammatory response and oxidative stress mechanism. Vitamin D has multiple benefits in biological activities particularly respiratory system disease. Method: In this research, 20 male Wistar rats were randomly allocated into four groups (5 rats /group) as follow: Group1 received saline as (negative control) group. The group 2 received a single IT instillation of silica (positive control) group; the group 3 was co-administrated with single IT silica and Vitamin D (20 mg/kg/day) daily for a period of 90 days. The rats of group 4 received Vitamin D daily for a period of 90 days. Results: Silica significantly increased serum and lung total Oxidant Status (TOS). Meanwhile, silica reduced serum and lung total antioxidant capacity (TAC), GSH and tumor necrosis factor-α (TNF-a). Vitamin D treatment meaningfully reversed oxidative stress, antioxidants status and inflammatory response. Also, Vitamin D improved histopathological changes caused by silica. Conclusion: These findings indicate that Vitamin D exerts protective effects against silica-induced lung injury. It seems that Vitamin D has potential use as a therapeutic object for silica induced lung injure.

• Advances in nano research
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• v.14 no.5
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• pp.435-442
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• 2023

Sports activities, including playing tennis, are popular with many people. As this industry has become more professionalized, investors and those involved in sports are sure to pay attention to any tool that improves athletes' performance Tennis requires perfect coordination between hands, eyes, and the whole body. Consequently, to perform long-term sports, athletes must have enough muscle strength, flexibility, and endurance. Tennis rackets with new frames were manufactured because tennis players' performance depends on their rackets. These rackets are distinguished by their lighter weight. Composite rackets are available in many types, most of which are made from the latest composite materials. During physical exercise with a tennis racket, nanocomposite materials have a significant effect on reducing injuries. Materials as strong as graphite and thermoplastic can be used to produce these composites that include both fiber and filament. Polyamide is a thermoplastic typically used in composites as a matrix. In today's manufacturing process, materials are made more flexible, structurally more vital, and lighter. This paper discusses the production, testing, and structural analysis of a new polyamide/Multi-walled carbon nanotube nanocomposite. This polyamide can be a suitable substitute for other composite materials in the tennis racket frame. By compression polymerization, polyamide was synthesized. The functionalization of Multi-walled carbon nanotube (MWCNT) was achieved using sulfuric acid and nitric acid, followed by ultrasonic preparation of nanocomposite materials with weight percentages of 5, 10, and 15. Fourier transform infrared (FTIR) and Nuclear magnetic resonance (NMR) confirmed a synthesized nanocomposite structure. Nanocomposites were tested for thermal resistance using the simultaneous thermal analysis (DTA-TG) method. scanning electron microscopy (SEM) analysis was used to determine pores' size, structure, and surface area. An X-ray diffraction analysis (XRD) analysis was used to determine their amorphous nature.

• Journal of Trauma and Injury
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• v.36 no.3
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• pp.231-241
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• 2023

Purpose: Overtriage and undertriage rates are critical metrics in trauma, influenced by both trauma team activation (TTA) criteria and compliance with these criteria. Analysis of undertriaged patients at a level I trauma center revealed suboptimal compliance with existing criteria. This study assessed triage patterns after implementing compliance-focused process interventions. Methods: A physician-driven, free-text alert system was modified to a nonphysician, hospital dispatcher-guided system. The latter employed dropdown menus to maximize compliance with criteria. The preintervention period included patients who presented between May 12, 2020, and December 31, 2020. The postintervention period incorporated patients who presented from May 12, 2021, through December 31, 2021. We evaluated appropriate triage, overtriage, and undertriage using the Standardized Trauma Assessment Tool. Statistical analyses were conducted with an α level of 0.05. Results: The new system was associated with improved compliance with existing TTA criteria (from 70.3% to 79.3%, P=0.023) and decreased undertriage (from 6.0% to 3.2%, P=0.002) at the expense of increasing overtriage (from 46.6% to 57.4%, P<0.001), ultimately decreasing the appropriate triage rate (from 78.4% to 74.6%, P=0.007). Conclusions: This study assessed a workflow change designed to improve compliance with TTA criteria. Improved compliance decreased undertriage to below the target threshold of 5%, albeit at the expense of increased overtriage. The decrease in appropriate triage despite compliance improvements suggests that the current criteria at this institution are not adequately tailored to optimally balance the minimization of undertriage and overtriage. This finding underscores the importance of improved compliance in evaluating the efficacy of TTA criteria.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.52-52
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• 2023

Ageing has been known to be deeply related to oxidative activities. Furthermore, inflammation is a response initiated by conditions such as infection and injury. It has been known that complex connections occur between oxidative stress and the inflammatory response, however underlying mechanism needs to be investigated. Chinese resource plants have been widely used as functional food and medicine for a long time, however it is not studied well how many of these resource plants work. We first decided testing anti-oxidant and anti-inflammatory activities with 95% ethanol extracts of the chinese resource plants, Boehmeria pilosinscula (Blume) Hassk., Carlemannia tetragona Hook f. and Clausena emarginata C.C.Huang. To measure anti-oxidant activity, we performed DPPH assay in Raw264.7 cells with 95% ethanol extracts. Clausena extracts showed significantly higher anti-oxidant activity than those of Boehmeria and Carlemannia. We then performed Nitric Oxide assay to measure the inflammation suppression levels with 95% ethanol extracts of these plants. Clausena extracts showed significantly higher suppression of nitric oxide production than those of Boehmeria and Carlemannia. This indicates that inflammation levels are significantly reduced by Clausena. After measuring anti-oxidant and anti-inflammatory activities, we then performed MTT assay to measure the cell survival rate of Raw264.7 cells treated with these extracts. Boehmeria showed much more cell survival rate than Carlemannia and Clausena. Taken together, this result suggests that Clausena extracts have more anti-oxidant and antiinflammatory activities than Boehmeria and Carlemannia, while Boehmeria extracts have more cell survival rate than Carlemannia and Clausena.

• Journal of the Korean Burn Society
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• v.24 no.2
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• pp.21-29
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• 2021

Purpose: Frostbite is a hazard to people exposed to cold environments. With the progression of modern industrial development and change of leisure behavior encountering cold environments, frequent accidental exposure to frostbite injury during work and human behavior is increasing, and the predisposing factors of frostbite were greatly changed than before. The purpose of this study was to make epidemiological analysis, and to review the treatment outcomes of frostbite. Methods: From March 2010 to February 2021, this study has included 27 patients with second- to third-degree frostbite injuries in Advanced Burn Reconstruction Center, Bundang Jesaeng Hosptial. A retrospective study was made about the distribution of age, gender, predisposing factors, prevalent area, type of managements, and the length of treatment period. Results: In our institution, acute management of frostbite patients has included rewarming, anticoagulation therapy (acetylsalicylic acid), and agents to improve vascular perfusion (lipo-prostaglandin E1 [Eglandin^®]). The 25 frostbite patients with second-degree frostbite (92.6%) were successfully managed by the conservative treatment alone with a mean of 20.3 days healing time. Two patients with third-degree frostbite (7.4%) also showed good outcomes after surgical reconstruction with a mean of 59 days healing time. In our clinical experiences of third-degree frostbite, definitive surgical reconstruction should be recommended to wait for more than 4~6 weeks for identification of clear demarcation of necrotic tissue caused by frostbite. In this study, 43 frostbite injuries site in 27 frostbite patients occurred. Among them, 15 patients (55.6%) had multiple-site frostbite injury. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments (40.8%), misapplying ice pack for treatment purposes (7.4%), barefoot walking on the cold ground (3.7%), and loss of consciousness in cold grounds (3.7%). The most prevalent sites of frostbite injuries revealed as the hand (58.1%), followed by the foot (32.6%), face (7.0%), and abdomen (2.3%). And in the winter season from the November to March, the incidence rate of frostbite injuries was high at 74.1%. Conclusion: This study included 27 frostbite patients with 43 frostbite sites since last decade in a single institution at the community hospital. The frostbite patients with second-degree frostbite (92.6%) were successfully healed by the conservative treatment alone with a mean of 20.3 days healing time. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments, etc. The most prevalent site of frostbite injuries was the hand (58.1%). And the most prevalent seasonal incidence of frostbite was from November to March (74.1%).

• Journal of the Korean Society of Safety
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• v.33 no.5
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• pp.170-176
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• 2018

Laboratory inspection and diagnosis is a means of investigating and assessing various hazards or the state of research equipment in a laboratory, then taking appropriate safety measures to prevent accidents and injury. In many cases, laboratory inspection and diagnosis carried out by agencies are performed in a perfunctory manner that only barely satisfies the legal requirements. The aim of the present study is to provide clearly established pricing criteria for laboratory inspection and diagnosis, so as to prevent recurrence of laboratory accidents and to establish a safe laboratory environment. In order to clarify previously unclear matters, such as the lower limit for bids submitted by laboratory inspection and diagnosis agencies, technical manpower requirements, and number of laboratories inspected and diagnosed per day, a questionnaire survey was administered to agency personnel. First, when asked what the lower limit for bids submitted by agencies should be in order to improve reliability of inspection and diagnosis results and make up for the shortcomings of the lowest-bidder-wins system, 85.5% of respondents answered that the lower limit for bids should stand at no lower than 90% of the estimated price. The level of technical expertise among the technical personnel committed to laboratory inspection and diagnosis was shown to impact the reliability of results, and questionnaire results indicated a need to vary technical expertise levels depending on the degree of hazard, substances handled, and equipment used in a given laboratory. Level of technical expertise(67.1%) and number of personnel(52.6%) were shown to have a greater impact on reliability of diagnosis than on reliability of inspection. According to the results, it is determined that three persons(specialist, advanced and intermediate) should be committed to inspections, while four persons(professional, specialist, advanced and intermediate) should be committed to diagnoses. The respondents indicated a larger number of laboratories could be inspected than diagnosed per day. This can be attributed to differences in the amount of work each task involves, and the time each task takes. Assuming a six-hour work day not counting transportation, paperwork and rest, it is thought that inspection of up to 36 laboratories will be possible if each laboratory is assigned no more than 10 minutes(34.7%), while up to 24 laboratories could be inspected and diagnosed if each laboratory is assigned 15 to 20 minutes(35.1%).

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.2
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• pp.175-187
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• 2014

The subways play an important part in serious traffic problems. Almost seven million citizens a day are using subways as a means of traffic communication in the Seoul metropolitan city in 2012. However, the subway system is a semi-closed environment, so many serious problems occurred in subway stations and injured passengers' health. Platform screen doors (PSD) are expected to prevent negligent accident such as injury or death from falling and improve the air quality of the subway station. Installation of PSD at stations in Seoul metropolitan subway had been completed in December 2009. Consequently, the underground transportation system became a closed environment, so the air quality has improved the platforms, but it has deteriorated in the tunnels. Especially, the subway cabin has many doors, and the doors are frequently opened and closed. For this reason, the effect of door opening on subway cabin, dust flow inside the subway cabin. In this process, the maintenance work may influence the health of people who work underground, as well as that of subway users (passengers). In this study, we measured air quality inside and outside of the subway cabin line 2 in Seoul, Korea. This study focused on the investigation of Indoor Air Quality (IAQ) and measurement target pollutants are PM10, CO, $CO_2$, $NO_2$, $O_3$. It was found that levels of PM10, $CO_2$, and $NO_2$ inside subway cabin line 2 exceeded the Korea IAQ standard. Concentrations of PM10, $CO_2$, and $NO_2$ inside of the cabin are higher than outside of the cabin (Indoor Outdoor ratio is higher than 1.). Concentrations of CO, $O_3$ inside of the cabin are lower than outside of the cabin (Indoor Outdoor ratio is lower than 1.). There is a high correlation between $CO_2$ and passengers inside of the cabin and PM10 is only the weakest correlation with passengers. Therefore, it is important to find out the emission source of $NO_2$. The results of this study will be useful as fundamental data to study indoor air quality of a subway cabin.