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We aimed to characterize the genomes of monkeypox virus isolates from the Far East, providing insights into viral transmission and evolution. Genomic analysis was conducted on 8 isolates obtained from patients with monkeypox virus disease in the Republic of Korea between May 2022 and early 2023. These isolates were classified into Clade IIb. Distinct lineages, including B.1.1, A.2.1, and B.1.3, were observed in 2022 and 2023 isolates, with only the B.1.3 lineage detected in six isolates of 2023. These genetic features were specific to Far East isolates (the Republic of Korea, Japan, and Taiwan), distinguishing them from the diverse lineages found in the Americas, Europe, Africa, and Oceania. In early 2023, the prevalence of the B.1.3 lineage of monkeypox virus identified in six patients with no overseas travel history is considered as an indicator of the potential initiation of local transmission in the Republic of Korea.
Subject(s)
Genome, Viral , Monkeypox virus , Mpox (monkeypox) , Phylogeny , Republic of Korea/epidemiology , Humans , Mpox (monkeypox)/epidemiology , Mpox (monkeypox)/virology , Monkeypox virus/genetics , Monkeypox virus/isolation & purification , Epidemics , Genomics/methods , Male , RNA, Viral/genetics , FemaleABSTRACT
This study introduces a novel concrete-filled tube (CFT) column system featuring a steel tube comprised of four internal triangular units. The incorporation of these internal triangular units serves to reduce the width-thickness ratio of the steel tube and augment the effective confinement area of the infilled concrete. This design enhancement is anticipated to result in improved structural strength and ductility, contributing to enhanced overall performance and sustainability. To assess the effectiveness of the newly proposed column system, a full-scale test was conducted on five square steel tube column specimens subjected to axial compression. Among these specimens, two adhered to the conventional steel tube column design, while the remaining three featured the new CFT columns with internal triangular units. The shape of the CFT column, the presence of infilled concrete and the presence of openings on the ITUs were considered as test parameters. The test results reveal that the ductility of the newly proposed CFT column system exhibited a minimum 30% improvement compared to the conventional CFT column. In addition, the initial stiffness and axial compressive strength of the new system were found to be comparable to those of the conventional CFT column.
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Data Compression , Compressive Strength , Physical Phenomena , Steel , Tensile StrengthABSTRACT
INTRODUCTION: Firefighters, compared to other occupational groups, are exposed more frequently in their working environment not only to physical issues, such as musculoskeletal disease, respiratory disease, and burns but also to mental health issues, such as PTSD and depression. Specifically, Korean firefighters experience significantly higher rates of work-related injuries compared to those in other countries. Recent statistics from the Korea National Fire Agency indicate a steady increase in the number of firefighting work-related injuries. However, there is a shortage of measures in place to address these issues. This study aims to investigate the health needs, overall healthcare usage, and unmet needs of firefighters in Korea. We also aim to investigate, through in-depth interviews, perceptions and hindering factors for integrative medicine approaches to fulfilling unmet needs. METHOD: This study was conducted in accordance with the consolidated criteria for reporting qualitative research. Convenience and snowball sampling methods will be used to recruit firefighters to participate in the study, and interviews will be conducted using a semi-structured interview guide. The data will be analyzed in four stages using the qualitative analysis method of Krippendorff. DISCUSSION: In this study, we examine the state of health issues and healthcare usage among Korean firefighters and investigate their perceptions of and needs for integrative medicine. In this way, we aim to explore how integrative medicine and Korean medicine approaches could improve and assist healthcare services for firefighters. Furthermore, our findings will provide policymakers and healthcare providers with the necessary basic information to develop integrative medicine systems suited to firefighters.
Subject(s)
Firefighters , Fires , Occupational Injuries , Humans , Qualitative Research , Republic of KoreaABSTRACT
Following the worldwide surge in mpox (monkeypox) in 2022, cases have persisted in Asia, including South Korea, and sexual contact is presumed as the predominant mode of transmission, with a discernible surge in prevalence among immunocompromised patients. Drugs such as tecovirimat can result in drug-resistant mutations, presenting obstacles to treatment. This study aimed to ascertain the presence of tecovirimat-related resistant mutations through genomic analysis of the monkeypox virus isolated from a reported case involving prolonged viral shedding in South Korea. Here, tecovirimat-resistant mutations, previously identified in the B.1 clade, were observed in the B.1.3 clade, predominant in South Korea. These mutations exhibited diverse patterns across different samples from the same patient and reflected the varied distribution of viral subpopulations in different anatomical regions. The A290V and A288P mutant strains we isolated hold promise for elucidating these mechanisms, enabling a comprehensive analysis of viral pathogenesis, replication strategies, and host interactions. Our findings imply that acquired drug-resistant mutations, may present a challenge to individual patient treatment. Moreover, they have the potential to give rise to transmitted drug-resistant mutations, thereby imposing a burden on the public health system. Consequently, the meticulous genomic surveillance among immunocompromised patients, conducted in this research, assumes paramount importance.
Subject(s)
Benzamides , Immunocompromised Host , Humans , Virus Shedding , Isoindoles , Mutation , Republic of KoreaABSTRACT
Knowledge of input blood to the brain, which is represented as total cerebral blood flow (tCBF), is important in evaluating brain health. Phase-contrast (PC) magnetic resonance imaging (MRI) enables blood velocity mapping, allowing for noninvasive measurements of tCBF. In the procedure, manual selection of brain-feeding arteries is an essential step, but is time-consuming and often subjective. Thus, the purpose of this work was to develop and validate a deep learning (DL)-based technique for automated tCBF quantifications. To enhance the DL segmentation performance on arterial blood vessels, in the preprocessing step magnitude and phase images of PC MRI were multiplied several times. Thereafter, a U-Net was trained on 218 images for three-class segmentation. Network performance was evaluated in terms of the Dice coefficient and the intersection-over-union (IoU) on 40 test images, and additionally, on externally acquired 20 datasets. Finally, tCBF was calculated from the DL-predicted vessel segmentation maps, and its accuracy was statistically assessed with the correlation of determination (R2), the intraclass correlation coefficient (ICC), paired t-tests, and Bland-Altman analysis, in comparison to manually derived values. Overall, the DL segmentation network provided accurate labeling of arterial blood vessels for both internal (Dice=0.92, IoU=0.86) and external (Dice=0.90, IoU=0.82) tests. Furthermore, statistical analyses for tCBF estimates revealed good agreement between automated versus manual quantifications in both internal (R2=0.85, ICC=0.91, p=0.52) and external (R2=0.88, ICC=0.93, p=0.88) test groups. The results suggest feasibility of a simple and automated protocol for quantifying tCBF from neck PC MRI and deep learning.
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PURPOSE: This study aimed to examine the role of parental monitoring and help seeking in the relationship between cyberbullying victimization and suicidal thoughts and behaviors in male and female college students. METHOD: Data were collected for 336 college students (71.72% female and 28.28% male) aged 18 to 24 or older years from two universities in the Midwest and the South Central regions. RESULTS: Logistic regression indicated the interaction term of cyberbullying victimization and parental monitoring was negatively related to suicidal thoughts and behaviors in a male group (B = -.155, p < .05, Exp(B) = .86). DISCUSSION: Male students whose parents monitored about being safe on the computer had dramatically fewer suicidal thoughts/behaviors. In both male and female groups, seeking professional help was not a significant moderator that weakened the relationship. CONCLUSION: There is a need for additional research on the importance of prevention and intervention efforts to foster open dialogue between students and their parents.
Subject(s)
Crime Victims , Cyberbullying , Humans , Male , Female , Suicidal Ideation , Students , ParentsABSTRACT
Rose crown gall caused by Agrobacterium tumefaciens is a major disease that damages the production of cut-roses in Korea. The effective prevention methods for this disease include the use of resistant varieties. This study was conducted to evaluate the resistance of 58 Korean cultivars and six foreign cultivars to crown gall disease with nodal explants in vitro. Among 180 A. tumefaciens strains, pathogenic strain RC12 was selected as an inoculant strain. The strain RC12 was identified based on characteristics of some selective media, pathogenicity test, and polymerase chain reaction analysis. Forty rose cultivars formed tumors on explants inoculated with A. tumefaciens RC12. However, 24 cultivars, including 22 Korean cultivars and 2 foreign cultivars, showed resistance to A. tumefaciens RC12 without forming any tumors. Six cultivars with tumor formation rates of over 30% formed initial tumors within 23 days after inoculation. Six cultivars with low tumor formation rates of around 5% formed initial tumors after 28 days of inoculation. It was found that gall formation rate was highly correlated with the initial gall formation period. Thus, the relationship between the period of gall formation and the rate of gall formation could be useful for assessing resistance to crown gall disease. In vitro inoculation methods could be used to evaluate resistance of cut-rose cultivars to crown gall diseases.
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OBJECTIVE: Guided by the routine activity theory, the current study proposes and tests pathways by which an absence of a capable guardian can contribute to interactions with motivated offenders and suitable targets, increasing the likelihood of teasing others and using alcohol. SAMPLE: The study participants consisted of 612 African American adolescents in four low-income neighborhoods in Chicago's Southside. MEASURES: Measures include alcohol use, absence of a capable guardian, the presence of a motivated offender, target suitability, and teasing. Covariates include age, biological sex, and government assistance. Analyses included descriptive statistics, correlation analysis, and structural equation modeling. RESULTS: The absence of a capable guardian variable positively correlated with the presence of a motivated offender. The presence of a motivated offender variable was positively associated with target suitability, which was positively related to teasing and alcohol use. The presence of a motivated offender and target suitability variables were positively associated with teasing and alcohol use. CONCLUSION: Findings highlight the importance of capable guardians and potentially have implications for nursing practice.
Subject(s)
Black or African American , Poverty , Humans , Adolescent , Chicago , Alcohol DrinkingABSTRACT
This study aimed to investigate the association between polyvictimization and offline and online sexual harassment and whether the association might be mediated by internalizing problems, low school satisfaction, and dropping out of school. The analytic sample was derived from the Children and Youth Rights Survey in South Korea. It consisted of 6353 adolescents' responses to the sexual harassment question and a set of other questions in the middle and high school questionnaires. The findings showed a direct association between polyvictimization and offline and online sexual harassment. Adolescents who were polyvictimized were more likely to be victims of both forms of sexual harassment. Furthermore, polyvictimization was positively related to dropping out of school, which was positively associated with offline sexual harassment. The findings from the study have significant implications for future research and practice.
Subject(s)
Bullying , Crime Victims , Sexual Harassment , Adolescent , Child , Humans , Surveys and Questionnaires , East Asian People , Republic of KoreaABSTRACT
High-fat and high-salt diets are risk factors for metabolic syndrome development. However, gochujang, which has a high salt content, possesses antiobesity properties in cell and animal models. We aimed to evaluate the effects of Sunchang traditional and modern factory produced gochujang on metabolic syndrome factors in high-fat diet (HFD)-induced obese mice. For 14 weeks, 4-week-old C57BL/6J male mice were separated into five groups and fed a normal diet (ND), a high-fat diet only (HD), a HD with salt (SALT), a HD with traditional Sunchang gochujang (TS), and HD with modern factory made Sunchang gochujang (FS). Compared to HD and SALT groups, the gochujang groups had lower body weight, blood leptin, and insulin levels with reduced Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index and improved serum and liver lipid profiles. In addition, gochujang supplemented groups exhibited a significant reduction in mRNA expression of anabolic lipid metabolism related factors; PPARγ, CEBPα, and FABP4, and a significant increase in mRNA expression of energy expenditure-related factors; PPARα and CPT1. Protein expressions of SREBP1 were downregulated in the gochujang fed groups. TS and FS intakes improved obesity in HFD-induced obese mice. Compared to the gochujang groups, the SALT group did not exhibit any of those benefits suggesting that the high salt content of gochujang has different effects compared with added salt alone. Our findings provide evidence that gochujang could be a functional food to attenuate metabolic syndrome.
Subject(s)
Insulin Resistance , Metabolic Syndrome , Animals , Mice , Male , Mice, Obese , Diet, High-Fat/adverse effects , Metabolic Syndrome/etiology , Metabolic Syndrome/metabolism , Mice, Inbred C57BL , Obesity/metabolism , Liver/metabolism , RNA, Messenger/metabolismABSTRACT
Peer-to-peer (P2P) accommodation markets have been disrupted by the COVID-19 pandemic. However, little attention is paid to how to remedy the disruption in terms of P2P accommodation performance. This study empirically investigates the spatially heterogeneous COVID-19 disruptions in the Airbnb business and offers place-based remedying strategies through local resources, including tourism clusters and community resilience. Using real data on Airbnb operating performance and local resources in Florida, we employ spatial econometric models and visualization techniques to estimate the pandemic-disrupted Airbnb performance model. The results show that leisure and hospitality clusters and three resilience resources-social, community capital, and environmental-had spatially heterogeneous effects on Airbnb revenue and booking performance across Floridian counties during the pandemic. Furthermore, community resilience moderated the effect of tourism clusters on Airbnb performance across individual and subclustered counties. These findings enable P2P accommodation hosts and policymakers to adopt destination-specific remedying strategies to cope with the pandemic.
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This study retrospectively reviews the medical service usage data of North Korean arrivals collected from 2015 to 2019. The purpose of this study is to understand the medical use status of North Korean arrivals and to design health policies for them. We reviewed 32,653 medical records of North Korean arrivals who visited the National Medical Center as outpatients and inpatients during a 5-year period. Among 1453 patients with an average age of 46.7 years, we found that among the treated patients, there were many women in their 40s and 50s who complained of psychiatric disorders. The most frequently visited department was psychiatry. The most frequently diagnosed disorder was unspecified depression. 88% of patients utilized Medical Care assistance type 1, which means that they are medical aid beneficiaries because they are usually in difficult economic circumstances. Medical examination and treatment fees of North Korean arrivals increased in general, and older patients paid more. Among North Korean arrivals, middle-aged women and mentally ill patients showed high medical needs. This study recommends that the government provide policy support to North Korean arrivals for professional psychiatric treatment and improvement of medical access. We also expect these results to be applied to the health problems of other refugees.
Subject(s)
Mental Disorders , Refugees , Middle Aged , Humans , Female , Retrospective Studies , Democratic People's Republic of Korea/epidemiology , Republic of Korea/epidemiology , Refugees/psychology , Mental Disorders/epidemiology , Mental Disorders/therapyABSTRACT
We report the complete genome sequence of the monkeypox virus strain MPXV-ROK-P1-2022, isolated from the first patient diagnosed with monkeypox in the Republic of Korea in June 2022. The virus was fully sequenced on the Illumina MiSeq instrument, and the phylogenetic tree showed that the strain belongs to lineage B.1.1.
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The National Institute of Environmental Research, under the Ministry of Environment of Korea, provides two-day forecasts, through AirKorea, of the concentration of particulate matter with diameters of ≤ 2.5 µm (PM2.5) in terms of four grades (low, moderate, high, and very high) over 19 districts nationwide. Particulate grades are subjectively designated by human forecasters based on forecast results from the Community Multiscale Air Quality (CMAQ) and artificial intelligence (AI) models in conjunction with weather patterns. This study evaluates forecasts from the long short-term memory (LSTM) algorithm relative to those from CMAQ-solely and AirKorea using observations from 2019. The skills of the one-day PM2.5 forecasts over the 19 districts were 39-70% for CMAQ, 72-79% for LSTM, and 73-80% for AirKorea; the AI forecasts showed comparable skills to the human forecasters at AirKorea. The one-day forecast skill levels of high and very high PM2.5 pollution grades are 31-98%, 31-74%, and 39-81% for the CMAQ-solely, the LSTM, and the AirKorea forecasts, respectively. Despite good skills for forecasting the high and very high events, CMAQ-solely forecasts also generate substantially higher false alarm rates (up to 86%) than the LSTM and AirKorea forecasts (up to 58%). Hence, applying only the LSTM model to the CMAQ forecasts can yield reasonable forecast skill levels comparable to the operational AirKorea forecasts that elaborately combine the CMAQ model, AI models, and human forecasters. The present results suggest that applications of appropriate AI models can greatly enhance PM2.5 forecast skills for Korea in a more objective way. Supplementary Information: The online version contains supplementary material available at 10.1007/s13143-022-00293-2.
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OBJECTIVES: Monkeypox outbreaks in nonendemic countries have been reported since early May 2022. The first case of monkeypox in the Republic of Korea was confirmed in a patient who traveled to Europe in June 2022, and an attempt was made to isolate and identify the monkeypox virus (MPXV) from the patient's specimens. METHODS: Clinical specimens from the patient were inoculated in Vero E6 cells. The isolated virus was identified as MPXV by the observation of cytopathic effects on Vero E6 cells, transmission electron microscopy, conventional polymerase chain reaction (PCR), and sequencing of PCR products. RESULTS: Cytopathic effects were observed in Vero E6 cells that were inoculated with skin lesion swab eluates. After multiple passages from the primary culture, orthopoxvirus morphology was observed using transmission electron microscopy. In addition, both MPXV-specific (F3L and ATI) and orthopoxvirus-specific genes (A39R, B2R, and HA) were confirmed by conventional PCR and Sanger sequencing. CONCLUSION: These results indicate the successful isolation and identification of MPXV from the first patient in the Republic of Korea. The isolated virus was named MPXV-ROK-P1-2022.
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The COVID-19 pandemic has led to an abrupt transition from face-to-face learning to online learning, which has also affected the mental health of college students. In this study, we examined the relationship between students' adjustment to online learning and their mental health by using the Dual-Continua Model. The model assumes that mental disorder and mental well-being are related yet distinct factors of mental health. For this purpose, 2,933 college students completed an online survey around the beginning of the Fall semester of 2020 (N = 1,724) and the Spring semester of 2021 (N = 1,209). We assessed participants' mental well-being, mental disorders, and academic distress by means of the online survey. In addition, we incorporated grades and log data accumulated in the Learning Management System (LMS) as objective learning indicators of academic achievement and engagement in online learning. Results revealed that two dimensions of mental health (i.e., mental well-being and mental disorder) were independently associated with all objective and subjective online learning indicators. Specifically, languishing (i.e., low levels of mental well-being) was negatively associated with student engagement derived from LMS log data and academic achievement and was positively associated with self-reported academic distress even after we controlled for the effects of mental disorder. In addition, mental disorder was negatively related to student engagement and academic achievement and was positively related to academic distress even after we controlled for the effects of mental well-being. These results remained notable even when we controlled for the effects of sociodemographic variables. Our findings imply that applying the Dual-Continua Model contributes to a better understanding of the relationship between college students' mental health and their adaptation to online learning. We suggest that it is imperative to implement university-wide interventions that promote mental well-being and alleviate psychological symptoms for students' successful adjustment to online learning.
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A rapid outbreak of monkeypox is ongoing in non-endemic countries since May 2022. We report the first case of monkeypox in the Republic of Korea. This occurred in a 34-year-old male patient who traveled to Europe in June 2022. On the day of his return to the Republic of Korea (June 21, 2022), the patient presented with a genital lesion. The results of the monkeypox real-time polymerase chain reaction tests were positive in the penile ulcer, oropharyngeal and nasopharyngeal specimens. The patient subsequently developed fever and skin rash after hospital admission. Careful history taking along physical examination should be conducted in the patients who have epidemiologic risk factors for monkeypox. Moreover, appropriate specimens should be obtained from lesions and tested for the monkeypox virus.
Subject(s)
Exanthema , Mpox (monkeypox) , Adult , Disease Outbreaks , Fever/etiology , Humans , Male , Mpox (monkeypox)/diagnosis , Mpox (monkeypox)/epidemiology , Monkeypox virus , Republic of Korea/epidemiologyABSTRACT
BACKGROUND: It has been reported that significant endothelial dysfunction or clinically evident vasospasm can be associated with drug-eluting stents (DESs). However, the impact of DES associated coronary artery spasm (CAS) on long-term clinical outcomes has not been fully elucidated as compared with those of patients with vasospastic angina. METHODS: A total of 2797 consecutive patients without significant coronary artery lesion (<70%), who underwent the Acetylcholine (Ach) provocation test, were enrolled between Nov 2004 and Oct 2010. DES-associated spasm was defined as significant CAS in proximal or distal to previously implanted DES site at follow-up angiography with Ach test. Patients were divided into two groups (DES-CAS; n = 108, CAS; n = 1878). For adjustment, propensity score matching (PSM) was done (C-statistics = 0.766, DES-CAS; n = 102, CAS; n = 102). SPSS 20 (Inc., Chicago, Illinois) was used to analyze this data. RESULTS: Baseline characteristics were worse in the DES-CAS group. After PSM, both baseline characteristics and the Ach test results were balanced except higher incidence of diffuse CAS and ECG change in the DES-CAS group. During Ach test, the incidence of diffuse spasm (93.1% vs. 81.3%, p = 0.012) and ST-T change (10.7% vs. 1.9%, p = 0.010) were higher in the DES-CAS group. At 3-year, before and after adjustment, the DES-CAS group showed a higher incidence of coronary revascularization (9.8% vs. 0.0%, p = 0.001), recurrent chest pain requiring follow up coronary angiography (CAG, 24.5% vs. 7.8%, p = 0.001) and major adverse cardiac events (MACEs, 9.8% vs. 0.9%, p < 0.005). CONCLUSION: In this study, DES associated CAS was associated with higher incidence of diffuse spasm, ST-T change and adverse 3-year clinical outcomes. Special caution should be exercised in this particular subset of patients.
Subject(s)
Coronary Vasospasm , Drug-Eluting Stents , Percutaneous Coronary Intervention , Acetylcholine/adverse effects , Coronary Angiography/methods , Coronary Vasospasm/diagnosis , Coronary Vasospasm/epidemiology , Coronary Vasospasm/etiology , Coronary Vessels/diagnostic imaging , Coronary Vessels/surgery , Drug-Eluting Stents/adverse effects , Humans , Propensity Score , Spasm/diagnosis , Spasm/epidemiology , Spasm/etiology , Treatment OutcomeABSTRACT
BACKGROUND: As the COVID-19 (Coronavirus disease 2019) pandemic is prolonged, psychological responses to the pandemic have changed, and a new scale to reflect these changes needs to be developed. In this study, we attempt to develop and validate the COVID-19 Impact Scale (CIS) to measure the psychological stress responses of the COVID-19 pandemic, including emotional responses and difficulty with activities of daily living. METHODS: We recruited 2152 participants. Participants completed the CIS, the Fear of COVID-19 Scale (FCV-19S), and other mental health related measures. The factor structure, reliability, and validity of the CIS were analyzed. In addition, the validity of the scale was confirmed by its relationships to the existing measures assessing fear of COVID-19, depression, anxiety, subjective well-being, and suicidal ideation. RESULTS: Using exploratory factor analysis (N1 = 1076), we derived a one-factor structure. In confirmatory factor analysis (N2 = 1076), the one-factor model showed good to excellent fitness. The CIS was positively correlated with depression, anxiety, suicidal ideation, fear of COVID-19 and negatively correlated with subjective well-being. The FCV-19S did not show significant correlations with subjective well-being or suicidal ideation, and FCV-19S's explanatory powers on depression and anxiety were lower than those of the CIS. CONCLUSIONS: These results support that the CIS is a valid assessment of emotional problems and deterioration of the quality of life caused by the COVID-19 pandemic. Finally, the limitations of this study and future research directions are discussed.
Subject(s)
COVID-19 , Activities of Daily Living , Humans , Pandemics , Quality of Life , Reproducibility of ResultsABSTRACT
The potentiality of Saccharomyces cerevisiae SRCM 501804 to remove arsenite (As[III]) in an aqueous solution was investigated in this study. The S. cerevisiae SRCM 501804 was isolated from Korean turbid rice wine (Makgeolli). The S. cerevisiae SRCM 501804 was characterized by phylogenetic analysis, Fourier transform infrared (FT-IR) spectroscopy, visual minerals technologies (MINTEQ) model, and point of zero charge (pHpzc). The relationship between the factors (pH, biosorbent dosage, contact time, and concentration) and biosorption capacity was investigated. The S. cerevisiae SRCM 501804 was removed 31.1-90.1% of the As(III) depending on the initial biomass dosage within 1 h. Co-existing anions in aqueous solution showed a negative influence on the biosorption performance of As(III) in the order Cl- > NO3- > SO42- > CO32-. The results of isotherms and kinetics suggested the Langmuir (R2 > 0.95) and Pseudo-second order (R2 > 0.99) models fit well with the equilibrium experimental data. The maximum biosorption capacity (qm) of S. cerevisiae SRCM 501804 biomass for As(III) was found to be 113.9 mg/g from Langmuir isotherm. Based on the results, it can be concluded that the biomass of S. cerevisiae SRCM 501804 could be used as an effective bio-sorbent for As(III) biosorption in an aqueous solution.