• Resources Recycling
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• v.10 no.4
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• pp.34-41
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• 2001

A research was performed to evaluate a use of shredder residue to currently dispose of at landfills. Laboratory analyses were conducted to determine especially the fuel characteristics of shredder residue. For this aim, shredder residue was classified by the particle size as well as by the type of material and the content of Cl, S, ash, and calorific value were determined. Due to the chlorinated plastic content of shredder residue, mean concentration of Cl was found to exceed 4wt% except one sample while that of S was ranged from 0.25 to 0.39 wt%. As far as calorific value was concemed, plastic was observed to be more than 10,000 kcal/kg while wood/paper and fiber accounted for approximately 4,000 kcal/kg. Shredder residue was found to contain varying trace amounts of metal elements, including Fe of 6∼8.5 wt%. Hg and Cr(VI) were not detected, however, while Cd was contained as small as 0.0004-0.0009 wt%.

• The Korean Journal of Applied Statistics
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• v.28 no.5
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• pp.1035-1046
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• 2015

Variance components models incorporate various random factors in the form of linear models. There are two experimental Layouts for the classification of factors under variance components models: nested classification and crossed classification. We consider two-way variance components models and investigate the effect of experimental Layout on the performance of model selection criteria AIC and BIC. The effect of experimental Layout is studied through a simulation study with various combinations of parameters in a systematic fashion. The simulation study shows differences in performance of model selection methods between the two classification. There is a particular tendency to prefer the smaller model than the true model when the variance component of a nested factor becomes relatively larger than a nesting factor that is persistent even when the sample size is not small.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.577-584
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• 1997

Validation and Standardization of neurobehavioral instrument in Korean occupational setting has not been studied ever. This study tried to validate the newly developed computerized psychomotor tests, Neurobehavioral Tests for Occupational Screening (NTOS). Male patients with Parkinson's disease(n=12) and male workers who never exposed to occupational neurotoxic materials and didn't have neurologic disease(n=21), performed some tests from NTOS; simple reaction time, choice reaction time(2 choice), and finger tapping(both hands). In simple analysis, difference between patient group and worker group was significantly great. Adjusted for age and education years, simple reaction time and finger tapping(both hand) were statistically significantly different between two groups(p<.05). Choice reaction time was also different(p<.1) but error frequency of choice reaction time test was not. Generally, this results showed NTOS could detect impairment of psychomotor function. But insensitive results of choice reaction time was partly due to small sample size and confounding variables and so required future study and refinement at improvement of NTOS.

• Journal of Welding and Joining
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• v.28 no.2
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• pp.66-73
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• 2010

Conventional fracture test of resistance spot weld had been performed without consideration of paint baking process in automobile manufacturing line. This study was aim to investigate the effect of paint baking on fracture mode and load carrying capacity in fracture test for resistance spot welded 780TRIP steels. With paint baking cycle after resistance spot welds, peel tests and microhardness were conducted on the as-welded and baked samples. Resistance spot welds in AHSS (Advanced High Strength Steels) are prone to display partial interfacial fractures during fracture test or vehicle crash. Baking cycle increased the load-carrying capacity of the resistance spot welded samples and improved the fracture appearance from partial to full button fracture for the L-type peel tests. Specially, the differences in fracture appearance are apparent when the nugget size of spot welds is small enough to produce the partial interfacial fracture. The comparison of macrohardness and microstructure between as-welded and baked samples showed that there are no large difference in change the fracture mode. However, the results of the instrumented indentation test suggested that fusion zone and HAZ of baked sample have less tensile and yield strength and proves that the tempering effects are applied and enhanced the resistance to fracture on welds with application of baking cycle.

• Journal of Menopausal Medicine
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• v.24 no.3
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• pp.204-209
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• 2018

Objectives: Aim of present study was designed to investigate the soporific effect of fennel among menopausal women. Methods: The present double-blinded and placebo-controlled trial examined the fennel effect on Pittsburgh Sleep Quality Index (PSQI). Total score and relevant 7 components, including sleep duration, sleep latency, use of sleeping medication, subjective sleep quality, sleep disturbances, daytime dysfunction and habitual sleep efficiency among 50 menopausal women compared to control group within a 12-week follow-up. Results: The patients in both groups reported no certain side effects and all subjects completed the study. The mean actual sleep duration was 5 hours and 66 minutes. Intergroup comparison revealed no statistically significant differences in the mean total PSQI score (P = 0.439), subjective sleep quality (P = 0.826), habitual sleep efficiency (P = 0.127), sleep disturbances (P = 0.130), use of sleeping medication (P = 0.52) and daytime dysfunction (P = 0.439). A tendency toward significant between 2 groups was seen concerning the sleep duration (P = 0.059). Intergroup comparison showed significantly borderline levels (P = 0.059). Conclusions: The treatment of 12 weeks with fennel caused a slight effect that did not reach to significant. These findings should be considered cautiously because of small sample size, short-term follow-up and subjective measure of sleep quality.

• Nutrition Research and Practice
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• v.13 no.6
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• pp.498-508
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• 2019

BACKGROUND/OBJECTIVES: Lower circulating 25-hydroxyvitamin D [25(OH)D] levels are associated with a higher risk of hypertension (HTN); however, it remains unclear whether the relationship is causal. We aimed to evaluate the causal effects of circulating 25(OH)D levels on the prevalence of HTN in the Korean population using the Mendelian randomization (MR) approach. SUBJECTS/METHODS: Epidemiological data, serum 25(OH)D data, and genomic DNA biospecimens were obtained from 2,591 participants, a subset of the study population in the Korea National Health and Nutrition Survey 2011-2012. Five 25(OH)D-related single nucleotide polymorphisms (SNPs; DHCR7 rs12785878, CYP2R1 rs10741657, CYP2R1 rs12794714, CYP24A1 rs6013897, and GC rs2282679), identified a priori from genome-wide association studies, were used as instrument variables (IVs) for serum 25(OH)D levels. In the MR analysis, we performed IV analyses using the two-stage least squares method. RESULTS: In the observational analysis, circulating 25(OH)D levels were found to be inversely associated with the HTN prevalence in ordinary least squares models (odds ratio: 0.97, 95% confidence interval: 0.96, 0.99) after adjusting for the potential confounders. There were differences in the circulating 25(OH)D levels across genotypes of individual SNPs. In the MR analysis, using individual SNPs as IVs, 25(OH)D levels were not associated with the HTN prevalence. CONCLUSIONS: We found no association between genetically determined circulating 25(OH)D levels and HTN in Korean adults. Our results are listed owing to the relatively small sample size and possible weak instrument bias; therefore, further studies are needed to confirm these results.

• Journal of Veterinary Science
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• v.22 no.3
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• pp.38.1-38.17
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• 2021

Background: The feline viral rhinotracheitis, calicivirus, and panleukopenia (FVRCP) vaccine, prepared from viruses grown in the Crandell-Rees feline kidney cell line, can induce antibodies to cross-react with feline kidney tissues. Objectives: This study surveyed the prevalence of autoantibodies to feline kidney tissues and their association with the frequency of FVRCP vaccination. Methods: Serum samples and kidneys were collected from 156 live and 26 cadaveric cats. Antibodies that bind to kidney tissues and antibodies to the FVRCP antigen were determined by enzyme-linked immunosorbent assay (ELISA), and kidney-bound antibody patterns were investigated by examining immunofluorescence. Proteins recognized by antibodies were identified by Western blot analysis. Results: The prevalences of autoantibodies that bind to kidney tissues in cats were 41% and 13% by ELISA and immunofluorescence, respectively. Kidney-bound antibodies were observed at interstitial cells, apical border, and cytoplasm of proximal and distal tubules; the antibodies were bound to proteins with molecular weights of 40, 47, 38, and 20 kDa. There was no direct link between vaccination and anti-kidney antibodies, but positive antibodies to kidney tissues were significantly associated with the anti-FVRCP antibody. The odds ratio or association in finding the autoantibody in cats with the antibody to FVRCP was 2.8 times higher than that in cats without the antibody to FVRCP. Conclusions: These preliminary results demonstrate an association between anti-FVRCP and anti-cat kidney tissues. However, an increase in the risk of inducing kidney-bound antibodies by repeat vaccinations could not be shown directly. It will be interesting to expand the sample size and follow-up on whether these autoantibodies can lead to kidney function impairment.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.4
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• pp.311-315
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• 2021

Objective: As clinicians and patients await consensus on intraovarian platelet-rich plasma (PRP) treatment, this project evaluated contemporary research trends in the literature. Methods: A PubMed/NLM search aggregated all ovarian PRP-related publications (n=54) to evaluate their scope, abstract utility, submission-to-publication interval, journal selected, article processing charge (APC), free reader access to full-text manuscripts, number and nationality of authors, and inclusion of international collaborators. The NIH Clinical Trials database was also audited. Results: Published output on intraovarian PRP has increased consistently since 2016, especially among investigators in Greece, Iran, USA, and Turkey. Between 2013 and 2021, 42 articles met the relevancy criteria, of which 40.5% reported clinical studies, small series, or case reports, 33% described experimental animal models, and 23.8% were opinion/review papers. Only two works included a placebo control group. The submission-to-publication interval (mean±standard deviation) was 130±96 days, there were 5.9±3.2 authors per project, and journals invoiced US $1,613±1,466 (range, $0-$3,860) for APCs. Conclusion: There was no correlation between APC and time to publish (Pearson's r=-0.01). Abstract content was inconsistent; sample size and patient age were often missing, yet free full-text "open access" was available for most publications (59.5%). The NIH Clinical Trials portal lists eight registered studies on "ovarian rejuvenation," of which two are actively recruiting patients, while four have been terminated or have an uncertain status. Two studies have concluded, with results from one posted to the NIH website. PRP and its derivatives for ovarian treatment show early promise, but require further investigation. Research is accelerating and should be encouraged, particularly placebo-controlled randomized clinical trials.

• Journal of Korean society of Dental Hygiene
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• v.19 no.5
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• pp.743-752
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• 2019

Objectives: Grip strength is a measure for assessing overall muscle strength, muscle mass, and nutritional status, and is a useful tool for early examination of a person's general health. Thus, this study analyzed the association between oral health-related factors and grip strength, using the 6th Korea National Health and Nutrition Examination Survey (KNHANES) data. Methods: Data were analyzed using the IBM SPSS version 25.0 (IBM Co., Armonk, NY, USA) software with a complex sampling analysis of stratified and clustered variables, all with weighted values, applied for every analysis conducted. From the 6th KNHANES data, a total of 26,101 people were selected as the study population. A complex sample generalized linear model analysis was performed for participants' sociodemographic characteristics, health status, use of oral care products, and factors such as adult mastication and speaking habits. Results: Grip strength was found to be higher among men compared to women. Grip strength was the highest in the 20-39 year old group. Furthermore, grip strength was statistically significantly higher among married and employed individuals, and in the right hand (p<0.001). Grip strength was statistically significantly higher among people who perceived themselves to have good health and among those who did not have health-related problems in the past two weeks (p<0.001). It was also higher among those who used interdental brushes and electronic toothbrushes (p<0.001), but decreased with greater discomfort in mastication and speaking among adults (p<0.05). Conclusions: Grip strength was found to be associated with oral health-related factors and therefore, these could be helpful tools in evaluating both general and subjective health statuses. In general, oral care products are small in size with oral care involving the use of hands and certain precise motions and actions to remove foreign substances in the oral cavity. As shown in the findings, grip strength declines with increased age and as a result, the use of oral care products should be strongly recommended in order to promote better general health.

• Journal of Acupuncture Research
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• v.38 no.2
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• pp.96-109
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• 2021

The purpose of this study was to evaluate the effectiveness and safety of acupotomy for the treatment of patients with knee osteoarthritis. There were 9 databases searched to retrieve randomized controlled trials until August 3, 2019 regarding acupotomy versus conventional Western medicine, conventional Western medicine treatment with and without acupotomy, and Korean medicine treatment with and without acupotomy, and meta-analysis was performed. Of 303 potentially relevant studies retrieved, 43 were systematically reviewed. All studies were conducted in China. Effective rate, visual analogue scale, and Western Ontario and McMaster Universities Osteoarthritis index were used as the evaluation scales. The Ashi point was selected most frequently. In all studies, the intervention group was more effective than the control group. Meta-analysis revealed that acupotomy showed statistically significant beneficial results. Although acupotomy had a beneficial effect on knee osteoarthritis, the risk of bias of the included studies was not low. The majority of the results from the evaluation scales used were highly heterogeneous (> 50%) which reduced confidence in the estimation of effect, or had a small sample size. Further clinical research and development is required in the future.