• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1808-1819
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• 2017

Knowledge on the functional characteristics and temporal variation of anaerobic bacterial populations is important for better understanding of the microbial process of two-stage anaerobic reactors. However, owing to the high diversity of anaerobic bacteria, close attention should be prioritized to the frequently abundant bacteria that were defined as core bacteria and putatively functionally important. In this study, using MiSeq sequencing technology, the core bacterial community of 98 operational taxonomic units (OTUs) was determined in a two-stage upflow blanket filter reactor treating pharmaceutical wastewater. The core bacterial community accounted for 61.66% of the total sequences and accurately predicted the sample location in the principal coordinates analysis scatter plot as the total bacterial OTUs did. The core bacterial community in the first-stage (FS) and second-stage (SS) reactors were generally distinct, in that the FS core bacterial community was indicated to be more related to a higher-level fermentation process, and the SS core bacterial community contained more microbes in syntrophic cooperation with methanogens. Moreover, the different responses of the FS and SS core bacterial communities to the temperature shock and influent disturbance caused by solid contamination were fully investigated. Co-occurring analysis at the Order level implied that Bacteroidales, Selenomonadales, Anaerolineales, Syneristales, and Thermotogales might play key roles in anaerobic digestion due to their high abundance and tight correlation with other microbes. These findings advance our knowledge about the core bacterial community and its temporal variability for future comparative research and improvement of the two-stage anaerobic system operation.

• Physical Therapy Korea
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• v.23 no.1
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• pp.38-45
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• 2016

Background: Chronic back pain shows a high correlation with lumbar disability, physical disability for daily activities, and psychosocial factors, such as depression. Object: The purpose of this study was to examine the correlation of the level of pain and disability with psychosocial factors, which are potential disturbance variables, in patients with chronic lumbar pain. Method: The sample included 258 patients, who had complained of chronic lumbar pain for more than three months. The Quadruple Visual Analogue Scale was used to measure the level of pain, and a Korean version of Oswestry Disability Index was used to measure the level of disability. Psychosocial factors were measured using the Tampa scale for Kinesiophobia-11, Fear Avoidance Beliefs Questionnaire, and Pain Self-Efficacy Questionnaire. The collected data was analyzed using PASW 18.0, and an independent samples t-test was used to examine frequency, percentage, mean, and standard deviation of sociodemographic characteristics and major variables. Pearson's correlation coefficient was used to investigate the correlation between the level of pain and disability and psychosocial factors. Stepwise multiple regression analysis was done to determine the level of pain and psychosocial factors of functional disorder. The significance level was set at ${\alpha}=.05$. Result: There is a strong correlation between the level of pain and functional disorder and psychosocial factors in patients with chronic lumbar pain. The study also revealed that as the levels of pain and fear avoidance increase, pain self-efficacy decreases. Conclusion: The results suggest that negative perceptions towards pain, limitations of physical movement, and severe fear avoidance directly affect the decrease in pain self-efficacy. Therefore, it is recommended to test pain self-efficacy when measuring the level of pain and disability in patients with chronic low back pain.

• Ocean and Polar Research
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• v.29 no.3
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• pp.205-216
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• 2007

The purpose of this study was to investigate effects of large scale marine sand mining on the marine ecological community. For the study, four stations along the coast were selected and monitored in 1998 and 2001 at mining areas and non-mining areas about the Gyeonggi Bay. The result revealed that in 1998, 9 species of fishes, 16 species of crustaceans, and 6 species of mollusks were collected where as in 2001, 11 species of fishes, 5 species of crustaceans, and 2 species of mollusks were collected, uncovering the fact that fishes have diversified while crustaceans and mollusks have reduced on a grand scale. Also, there were two key characteristics regarding the changes of biological communities in mining and nonmining areas. The first was the dwindling of crustaceans inhabiting the sand area. This outcome may be accounted for by the facts that physical removal of seabed sediments and re-sediment due to expansion of floating particles cause direct influence on the ocean floor ecosystem and have continuous effect on the communities of crustaceans which feed on them. Secondly, the newly arrived species and their population during spring and summer seasons have increased in the non-mining areas and have decreased in the mining area. It can be concluded that highly nomadic fish species migrate toward areas with less disturbance or destruction of ecosystem from marine sand mining, and consequently, the communities of fishes change in the sea area. Setting aside the characteristics of the investigated sea areas where the arriving conditions of species vary by seasons, the clear differences of population of organisms in those areas are due to environmental alterations owing to the marine sand mining ; if those large-scale marine sand mining activities continue in the Gyeonggi Bay, their effects on biological communities in the areas will only grow.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7555-7560
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• 2013

Background: Beedi rollers are exposed to unburnt tobacco dust through cutaneous and pharyngeal route and it is extremely harmful to the body since it is carcinogenic in nature and can cause cancer during long exposure. This indicates that occupational exposure to tobacco imposes considerable genotoxicity among beedi workers. Materials and Methods: In the present study, 27 beedi workers and age and sex matched controls were enrolled for clinical, cytogenetics and molecular analysis. Clinical features were recorded. The workers were in the age group of 28-67 years and were workers exposure from 8-60 years. Blood samples were collected from workers and control subjects and lymphocyte cultures were carried out by using standard technique, slides were prepared and 50 metaphases were scored for each sample to find the chromosomal abnormalities. For molecular analysis the genomic DNA was extracted from peripheral blood, to screen the variations in gene, the exon 1 of CYP1A1 gene was amplified by polymerase chain reaction (PCR) and then screened with Single Strand Conformation Polymorphism (SSCP) analysis. Results: A statistically significant increase was observed in the frequencies of chromosomal aberrations in exposed groups when compared to the respective controls and variations observed in Exon 1 of CYP1A1(Cytochrome P450, family 1, subfamily A, polypeptide 1) gene. Conclusions: This study shows that, the toxicants present in the beedi that enter into human body causes disturbance to normal state and behavior of the chromosomes which results in reshuffling of hereditary material causing chromosomal aberrations and genomic variations.

• Journal of the Korean Geosynthetics Society
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• v.11 no.1
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• pp.47-56
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• 2012

Discharge capacity of PBD is sensitive in proportion to thickness and ground condition, and drainage of PBD declines due to disturbance effect in surrounding ground by mandrel used for vertical drainage setting and setting machines and type. Also, deviation of discharge capacity gets larger according to ground condition, construction condition and soil properties. But cause and analysis of those problems like reduced discharge of capacity and delayed dissipation of pore water pressure for discharge capacity is lack. Thus, in this text, ground improvement and discharge capacity is investigated by implementing composite discharge capacity test for analysis of an effect factor of PBD discharge capacity with in-situ ground condition. After fixing the vertical drain on a cylindrical cylinder, put churned sample into the cylinder. After in-situ ground and reclamation of ground are dredged, load following the loading step of 30, 70 and 120kPa using a pressure device. Result of the test, The discharge capacity was SM>ML>CL>CL(dredged soil) in situ condition and more fine-grained content, the amount of discharge was greater.

• Journal of Food Hygiene and Safety
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• v.24 no.2
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• pp.124-127
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• 2009

The aim of this study is to evaluate the estrogenic activity of Cucurbita pepo seed extract which includes ${\beta}-sitosterol$ and other phytosterols. Sample was extracted from Cucurbita pepo seed by supercritical carbondioxide method and resuspended with ethanol. Estrogenic activity was measured by recombinant yeast assay which detects estrogenic activity using recombinant yeast with high level of estrogenic receptor. However, estrogenic activity of pumpkin seed extract was not found in this study. Based on this data, pumpkin seed extract will not cause estrogenic disturbance.

• The Korean Journal of Ecology
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• v.28 no.2
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• pp.79-83
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• 2005

We investigated the species richness of macrolepidoptera (including pyralid moths) in the evergreen broad-leaved forests of southwestern coast of Korea. The studied site was Mt. Duryunsan and its neighboring area, Haenam-gun, Jollanam-do and moths were identified and analyzed after collecting them with UV light traps from 2001 to 2004. A total number of species comprised 18 families and 489 species. We expected that the number of species would be increased when the species of microlepidoptera and butterflies were included. The family Noctuidae with 181 species was dominant in the area followed by Geometridae with 129 species and Pyralidae with 72 species. Based on number of collected individuals, Geometridae was the highest and followed by Noctuidae, Pyralidae and Drepanidae. Fifty-one percent of the total species consisted of less than two specimens in the collected sample. Monthly changes of numbers of species and individuals were examined and indices of Simpson's heterogeneity and evenness were also drawn. We briefly discussed the possibility of moth species or group of species as bioindicator for assessing the condition of forest after disturbance.

• The Korean Journal of Pain
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• v.34 no.2
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• pp.241-245
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• 2021

Background: It has been reported that a new type of headache may develop as a result of face mask use during the COVID-19 pandemic. The aim of this study is to investigate the clinical features of face mask-related headache during the COVID-19 pandemic. Methods: This is a cross-sectional study carried out on healthcare workers at the Afyonkarahisar Health Sciences University. The number of workers at our university was established. Sample size was calculated using the G*Power program. A questionnaire consisting of questions relating to pre-existing headache, an aggravation in headache, and de-novo headache was filled out by 3 neurologists with all participants. Results: Data was collected from a total of 375 participants, after the exclusion of 5 individuals who refused to participate. Out of all participants, 26 (6.9%) used a filtering mask, 274 (73.1%) used a surgical mask, 75 (20.0%) participants used a combination of both masks. The number of participants with preexisting headache was 114 (30.4%) had pre-existing headache. Of those with pre-existing headache, 77 (67.5%) healthcare workers had reported an aggravation in their headache after mask use. De-novo headache was observed in 116 (30.9%) of participants. De-novo headache characteristics included throbbing in 17 (14.7%) participants and pressing in 99 (85.3%) participants. In addition, symptoms such as tachypnea, sleep disturbance, and fatigue were found to be significantly higher. Conclusions: This study indicates that healthcare workers develop headaches due to use of masks during the COVID-19 outbreak.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5C
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• pp.333-342
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• 2006

In this study, a consolidometer for radially inward drainage under constant rate of strain (CRS) loading was developed. Their analytical solutions for evaluating consolidation characteristics of soils were also derived. With reconstituted kaolinite samples, comparative tests of the developed CRS loading consolidation in radially inward drainage together with incremental loading (IL) consolidation in radially inward, vertical and radially outward drainages and CRS loading consolidation in radially outward and vertical drainages were carried out. From the test results, It is confirmed that the results of the developed consolidometer were not only in good agreement with those of other consolidation tests but also they were more stable and reliable with less sample disturbance effect.

• Journal of Korean Academy of Dental Administration
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• v.11 no.1
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• pp.78-88
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• 2023

This study aimed to analyze the correlation between working from home and sleep disorders among domestic workers using data from the 5th Working Environment Survey in 2017. Out of the total 30,108 wage workers, 818 employees work from home and 4,090 work in an office. A random sample of 1:5 pairs, considering gender and occupational group, was selected from these employees as the study subjects. The analysis included personal characteristics, occupational characteristics, work-from-home arrangements, and sleep disorders. Age, education, employment status, years in the workforce, weekly working hours, work-life balance, self-perceived health, depression, and anxiety were all adjusted as potential confounding variables. Conditional logistic regression analysis was conducted to examine the relationship between working from home (independent variable) and sleep disorder (dependent variable). This analysis aimed to analyze the correlation between working from home and sleep disorder. The analysis revealed that working from home was associated with sleep onset latency disorder OR=3.23 (95% CI=2.67~3.91), sleep maintenance disorder OR=3.67 (95% CI=3.02~4.45), and non-restorative sleep OR=3.01 (95% CI=2.46~3.67), which showed a statistically significant relationship with all three types of sleep disorders. Factors influencing the correlation between working from home and sleep disorders included work-life balance, social isolation, and anxiety.