OBJECTIVES: This study examined how ethanolamines (EAs) with the same functional alcohol group (HOCH2CH2), such as mono-EA (MEA), di-EA (DEA), and tri-EA (TEA), in water-based metalworking fluids (wbMWFs) are vaporized, condensed, and transformed by heat generated during metalworking. METHODS: Two types of experimental apparatus were manufactured to achieve these objectives. RESULTS: Vaporization tests using a water bath showed that the vaporization rate increased markedly from 0.19 mg/m2.min at 23.5degrees C to 8.04 mg/m2.min at 60degrees C. Chamber tests with a heat bulb revealed that "spiked" MEA was fully recovered, while only 13.32% of DEA and no TEA were recovered. Interestingly, non-spiked types of EAs were detected, indicating that heat could convert EAs with more alcohol groups (TEA or DEA) into other EAs with fewer group(s) (DEA or MEA). The EA composition in fresh fluid was 4% DEA, 66% TEA, and 30% MEA, and in used fluids (n = 5) was 12.4% DEA, 68% TEA, and 23% MEA. Conversion from TEA into DEA may therefore contribute to the DEA increment. Airborne TEA was not detected in 13 samples taken from the central coolant system and near a conveyor belt where no machining work was performed. The DEA concentration was 0.45 mg/m3 in the only two samples from those locations. In contrast, airborne MEA was found in all samples (n = 53) regardless of the operation type. CONCLUSION: MEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.
Baths ; Ethanolamines ; Hot Temperature ; Tea ; Volatilization ; Water

Background: Ablative fractional CO2 laser treatment is popular for improving atrophic acne scars; however, complications after laser treatment are unavoidable. The purpose of this study was to investigate the efficacy and safety of a moisturizer containing Centella asiatica extract when applied after ablative fractional CO2 laser resurfacing. Methods: A split-face study was conducted between September 2020 and December 2020 on 34 patients (16 females and 18 males) who were treated with ablative fractional CO2 laser resurfacing. After laser treatment, C. asiatica extract was applied to the right side of the face and purified water was applied to the left side. We compared the right and left sides of the face at various time points after laser treatment using an automatic skin analysis device to investigate the degree of moisture and post-inflammatory hyperpigmentation. Results: No significant difference in the degree of moisture was found between the two sides of the face immediately after laser treatment (P=0.059), but there was a significant difference at 1 and 4 hours after post-laser treatment care (P<0.001). Regarding post-inflammatory hyperpigmentation, there was no significant difference between the two sides of the face before laser treatment (P=0.184), but a significant difference was found at 6 weeks after laser treatment (P<0.001). Conclusions Our results show that applying C. asiatica extract is a novel post-laser treatment modality that can provide satisfactory results without complications after ablative fractional CO2 laser resurfacing.

Background: Ablative fractional CO2 laser treatment is popular for improving atrophic acne scars; however, complications after laser treatment are unavoidable. The purpose of this study was to investigate the efficacy and safety of a moisturizer containing Centella asiatica extract when applied after ablative fractional CO2 laser resurfacing. Methods: A split-face study was conducted between September 2020 and December 2020 on 34 patients (16 females and 18 males) who were treated with ablative fractional CO2 laser resurfacing. After laser treatment, C. asiatica extract was applied to the right side of the face and purified water was applied to the left side. We compared the right and left sides of the face at various time points after laser treatment using an automatic skin analysis device to investigate the degree of moisture and post-inflammatory hyperpigmentation. Results: No significant difference in the degree of moisture was found between the two sides of the face immediately after laser treatment (P=0.059), but there was a significant difference at 1 and 4 hours after post-laser treatment care (P<0.001). Regarding post-inflammatory hyperpigmentation, there was no significant difference between the two sides of the face before laser treatment (P=0.184), but a significant difference was found at 6 weeks after laser treatment (P<0.001). Conclusions Our results show that applying C. asiatica extract is a novel post-laser treatment modality that can provide satisfactory results without complications after ablative fractional CO2 laser resurfacing.

Background: This study aimed to evaluate the efficacy and safety of a topical antioxidant cream containing tocotrienol after 1064-nm picosecond neodymium-doped yttrium aluminum garnet (Nd:YAG) laser treatment for environment-induced skin pigmentation. Methods: A split-face study was conducted between December 2020 and March 2021 in 26 patients (25 women and one man) who were treated with a 1064-nm picosecond Nd:YAG laser. On the right side of the face, an antioxidant cream containing tocotrienol was applied after picosecond laser treatment, and on the left side, only picosecond laser treatment was performed. We compared the right and left sides of the face at 4 weeks after laser treatment using an automatic skin analysis device to investigate skin pigmentation. The melasma severity scores of the two sides were evaluated before and 4 weeks after picosecond laser treatment. Results: The skin pigmentation score showed a significant difference between pretreatment and 4 weeks after picosecond laser treatment on both sides of the face (P<0.001), and there was a significant difference in skin pigmentation score improvement between the right and left sides (P<0.001). The melasma severity score showed a significant difference on the right side between pretreatment and 4 weeks after laser treatment (P<0.001), but there was no significant change on the left side (P>0.05). Conclusions Our results show that, for the treatment of environment-induced skin pigmentation, the application of a tocotrienol-containing antioxidant cream after 1064-nm picosecond laser treatment can provide good results without any complications.

Phthalates and bisphenol A (BPA) are synthetic chemicals widely used in daily life. This study investigated urinary phthalate and BPA levels in Korean children and their associations with obesity. Methods: A total of 2,351 children aged 3 to 17 years who participated in the Korean National Environmental Health Survey 2015 to 2017 were included. Urinary dilution was corrected using covariate-adjusted standardization (CAS). We examined the geometric mean (GM) concentrations of urinary phthalate metabolites, including di (2-ethylhexyl) phthalate (DEHP) metabolites (mono [2-ethyl-5-hydroxyhexyl] phthalate, mono [2-ethyl-5-oxohexyl] phthalate, and mono [2-ethyl-5-carboxypentyl] phthalate [MECPP]), mono-benzyl-phthalate (MBzP), mono (carboxyoctyl) phthalate (MCOP), mono (carboxy-isononyl) phthalate (MCNP), mono (3-carboxypropyl) phthalate, and mono-n-butyl-phthalate (MnBP), and BPA. We also analyzed the odds ratio (OR) for obesity according to the quartiles of each analyte. Results: The urinary GM levels of DEHP metabolites and MnBP were notably higher among Korean children than among American, Canadian, and German children. The CAS-applied GM concentrations of most analytes, except for MBzP, MCOP, and MCNP, were higher in children aged 3 to 5 years than in those aged 6 to 17 years. The OR for obesity in the highest quartile of MECPP was significantly higher than in the lowest quartile after adjusting for covariates. However, the other phthalate metabolites and BPA were not significantly associated with obesity. Conclusion: The concentrations of urinary DEHP metabolites and MnBP were higher in Korean children than in children in Western countries. Urinary MECPP exposure, but not other phthalates or BPA, showed a positive association with obesity in Korean children. Further studies are required to elucidate the causal relationships.

Background: This study aimed to evaluate the efficacy and safety of a topical antioxidant cream containing tocotrienol after 1064-nm picosecond neodymium-doped yttrium aluminum garnet (Nd:YAG) laser treatment for environment-induced skin pigmentation. Methods: A split-face study was conducted between December 2020 and March 2021 in 26 patients (25 women and one man) who were treated with a 1064-nm picosecond Nd:YAG laser. On the right side of the face, an antioxidant cream containing tocotrienol was applied after picosecond laser treatment, and on the left side, only picosecond laser treatment was performed. We compared the right and left sides of the face at 4 weeks after laser treatment using an automatic skin analysis device to investigate skin pigmentation. The melasma severity scores of the two sides were evaluated before and 4 weeks after picosecond laser treatment. Results: The skin pigmentation score showed a significant difference between pretreatment and 4 weeks after picosecond laser treatment on both sides of the face (P<0.001), and there was a significant difference in skin pigmentation score improvement between the right and left sides (P<0.001). The melasma severity score showed a significant difference on the right side between pretreatment and 4 weeks after laser treatment (P<0.001), but there was no significant change on the left side (P>0.05). Conclusions Our results show that, for the treatment of environment-induced skin pigmentation, the application of a tocotrienol-containing antioxidant cream after 1064-nm picosecond laser treatment can provide good results without any complications.

OBJECTIVES: In establishing policies for agricultural safety, evaluating injury burdens as well as investigating the rates and characteristics of work injury is important. This study investigated the types and characteristics of agricultural injury subjective burdens. METHODS: By analyzing the injured farmers identified in the 2013 Korean Farmers' Occupational Injury Survey, the burdens caused by injuries were categorized using one direct cost item (medical costs) and five indirect cost items (including productivity decreases and wage increases). Statistical differences among the burden items were analyzed using logistic regression analysis according to the characteristics of the farmers and their farm injuries. RESULTS: Among the subjective burdens indicated by the 457 injured farmers, disruption to work was most common. The major influences on each subjective burden item are as follows: for the item of disruption to work, age, time of injury occurrence, treatment period, and farming machine use were influential; for an increased family member's burden of farm works, the number of family members and treatment period were influential. Regarding cost burden of treatment, the results varied according to whether or not the patient was hospitalized and annual income. CONCLUSION: Subjective burdens induced by indirect costs rather than those induced by direct costs were found to be higher in ratio. In regard to each burden item, the results varied according to the characteristics of the farmers and their farm injuries. To support injured farmer, setting goals to reduce indirect cost burdens and preparing concrete methods is necessary.
Efficiency ; Humans ; Logistic Models ; Occupational Injuries ; Salaries and Fringe Benefits

Background: Malarplasty is widely performed for zygoma reduction. The effects of body segmentation, plate bending, and postoperative arch location on zygomatic movement have not been analyzed using computed tomography (CT). Results: We quantitatively analyzed the effects of surgical factors on zygomatic movements via superimposition of preoperative and postoperative CT images using three-dimensional software. Our results showed that segmentation had the most significant effect on the horizontal reduction of malar eminence (β = 0.593, r = 0.696, adjusted r2 0.479, F = 79.595; p < 0.001). In addition, upward and posterior arch movements had significant effects on the anteriorand posterior movements of the eminence (β = − 0.379 for vertical arch movement, β = 0.324 for arch setback, r = 0.603, adjusted r2 = 0.352, F = 31.943; p < 0.001). The major factors that influenced inward arch movement at thecoronoid process included segmentation and inward movement at the arch osteotomy site. To prevent interference of the coronoid process and arch, surgeons should pay attention to the degree of segmentation (β = 0.349) and inward movement at the arch osteotomy site (β = 0.494; r = 0.688, adjusted r2 = 0.464, F = 50.412; p < 0.001). Conclusions Surgical factors related to malarplasty affect the movement of specific parts of the zygoma. In addition, accurate application is possible by considering the anatomical structure of the application area when using the bending plate.

In the case of complete edentulous patients, as the mandibular alveolar bone absorption progresses, the maintenance and stability of the existing dentures, which had satisfactory functions in the past, are deteriorated. Despite of the need to fabricate new dentures, they often hesitate due to physical burdens on the duration and intensity of future treatment progress due to the effects of aging and systemic diseases. In the case of these completely edentulous patients, it is necessary to consider the treatment goals that can reduce the number of visits and the adaptation period for new dentures before starting the treatment. This case is a case of producing complete dentures of elderly patients with deteriorated physical ability. In addition to producing suction dentures through preliminary and definitive closed mouth functional impression suggested by Sato, CAD / CAM technique was used to transfer occlusal functional information of existing dentures to facilitate adaptation to new dentures.

Traditional removable partial denture is a successful treatment for partial edentulous patients. When the abutment is formed with unilateral minority teeth, satisfaction with the use of removable partial denture may be lowered due to patient's discomfort and damage of the abutment. Recently, it has been reported that the unilateral posterior extension partial denture is used as a bilateral posterior extension partial denture using implant fixed prostheses as abutments. In this case, by using implant surveyed crown prostheses, bilateral posterior extension partial denture is fabricated in site that is predicted to have a poor prognosis. This resulted in improved support, maintenance, and stabilization of the removable partial denture, which were economically beneficial to patient and satisfied with use.
Crowns ; Denture, Partial ; Denture, Partial, Removable ; Humans ; Prognosis ; Prostheses and Implants ; Tooth