• Journal of the Korea Society of Computer and Information
• /
• v.29 no.5
• /
• pp.21-29
• /
• 2024

Reducing the radiation dose during CT scanning can lower the risk of radiation exposure, but not only does the image resolution significantly deteriorate, but the effectiveness of diagnosis is reduced due to the generation of noise. Therefore, noise removal from CT images is a very important and essential processing process in the image restoration. Until now, there are limitations in removing only the noise by separating the noise and the original signal in the image area. In this paper, we aim to effectively remove noise from CT images using the wavelet transform-based GAN model, that is, the WT-GAN model in the frequency domain. The GAN model used here generates images with noise removed through a U-Net structured generator and a PatchGAN structured discriminator. To evaluate the performance of the WT-GAN model proposed in this paper, experiments were conducted on CT images damaged by various noises, namely Gaussian noise, Poisson noise, and speckle noise. As a result of the performance experiment, the WT-GAN model is better than the traditional filter, that is, the BM3D filter, as well as the existing deep learning models, such as DnCNN, CDAE model, and U-Net GAN model, in qualitative and quantitative measures, that is, PSNR (Peak Signal-to-Noise Ratio) and SSIM (Structural Similarity Index Measure) showed excellent results.

• Journal of Environmental Health Sciences
• /
• v.50 no.2
• /
• pp.102-112
• /
• 2024

Background: Despite the rise in the number of domestic indoor climbing gyms, there is a lack of specific hygiene standards and research on the holds installed in them. Holds can act as vectors for microbial transmission through the hands, posing a risk of infectious diseases, especially with damaged skin. Objectives: The aim of this study is to investigate the contamination level and species of microorganisms on holds according to the management methods practiced in indoor climbing gyms and identify effective strategies for reducing microbial contamination. Methods: We investigated factors that may influence microbial contamination of holds, including hold management methods, user information, and hygiene management at three climbing gyms in Seoul. A total of 72 holds were sampled, 18 for each management method of brushing, high-pressure washing, and ethanol disinfection. Samples were cultured on LB and blood agar at 37℃ for 48 hours to calculate CFUs. PCR assay targeting 16S rRNA was carried out to identify microorganisms. Dunn-Bonferroni was employed to see the microbial reduction effect of the management method and the difference in microbial contamination by management method and climbing gym. Results: As a result of microbial identification, microorganisms such as Bacillus, Staphylococcus, and Micrococcus, which were derived from various environments such as skin and soil, were discovered on the surface of the climbing hold. Among the discovered microorganisms, some species had potential pathogenic properties that could cause food poisoning, gastrointestinal disease, bacteremia, and sepsis. All hold management methods were effective in reducing microorganisms (p<0.05), with ethanol disinfection being the most effective (p<0.001). Conclusions: Our results indicate that there are potential pathogens on holds that demand thorough management for microbial prevention. Proposed methods include regular brushing and ethanol disinfection in addition to high-pressure washing with long cycles, which are the existing forms of hold management. Further studies on shoe management are advised to curb soil-derived microorganisms.

• Korean Circulation Journal
• /
• v.54 no.9
• /
• pp.549-561
• /
• 2024

Background and Objectives: The efficacy of sodium-glucose cotransporter-2 inhibitors (SGLT2i) may depend on renal function, and this raises theoretical concern over its effects on cardiovascular outcomes in patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD). Methods: This systematic review and updated meta-analysis of randomized controlled trials (RCTs) compared cardiovascular outcomes of patients with T2DM and CKD treated with SGLT2i to placebo. PubMed, Embase, and Cochrane were systematically searched. Prespecified subgroup analyses were performed in strata of estimated glomerular filtration rate (eGFR) of <45 mL/min/1.73 m² and 45 to 59 mL/min/1.73 m². Results: Nine RCTs comprising 29,146 patients were selected. Average follow-up ranged from 0.75 to 4.2 years. SGLT2i were shown to reduce the risk of all-cause mortality (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.79-0.97; p=0.01), the composite of cardiovascular mortality or hospitalizations for heart failure (HHF: HR, 0.71; 95% CI, 0.65-0.78; p<0.001), cardiovascular mortality (HR, 0.86; 95% CI, 0.76-0.98; p=0.02), HHF (HR, 0.62; 95% CI, 0.55-0.71; p<0.001), major adverse cardiovascular events (HR, 0.85; 95% CI, 0.77-0.94; p=0.002), stroke (HR, 0.76; 95% CI, 0.59-0.97; p=0.03), and myocardial infarction (HR, 0.78; 95% CI, 0.67-0.91; p=0.001). These findings were consistent over strata of eGFR, albeit with a lower incidence of stroke in patients treated with SGLT2i with eGFR <45 mL/min/1.73 m² (p-value for interaction=0.04). Conclusions: Compared with a placebo, patients with T2DM and CKD treated with SGLT2i experience a reduction in all-cause mortality, cardiovascular mortality, and HHF.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.37 no.4
• /
• pp.251-258
• /
• 2024

This study investigated the effect of bearing aging on the seismic response of a three-span continuous concrete girder bridge with pot bearings installed. The pot bearings were modeled as elastic springs in the longitudinal, transverse, and vertical directions of the bridge to reflect the stiffness of fixed and movable supports. The effect of bearing aging on the seismic response of the bridge was examined by considering two factors: a decrease in the horizontal stiffness of the fixed bearings and an increase in the horizontal stiffness of the movable bearings. The finite element model of the three-span continuous girder bridge was validated by comparing its numerical natural frequencies with the designed natural frequencies. Using artificial ground motions that conform to the design response spectrum specified by the KDS bridge seismic design code, the seismic responses of the bridge's girders and bearings were calculated, considering the bearing stiffness variation due to aging. The results of a numerical analysis revealed that a decrease in the horizontal stiffness of the fixed bearings led to an increase in the absolute maximum relative displacement of the bearings during an earthquake. This increases the risk of the mortar block that supports the bearing cracking and the anchor bolt breaking. However, an increase in the horizontal stiffness of the movable bearings due to aging decreased the absolute maximum shear on the fixed bearings. Despite the shear reduction in the fixed bearings, the aging of the pot bearings change could cause additional tensile bending stress in the girder section above the free bearings, which could lead to unexpected structural damage to the continuous bridge during an earthquake.

• Journal of agricultural medicine and community health
• /
• v.49 no.3
• /
• pp.257-270
• /
• 2024

Objective: This study aimed to empirically evaluate the effectiveness of chronic disease management services utilizing ICT for patients with chronic illnesses. Methods: From May to December, 2023, 452 people who were diagnosed with hypertension and diabetes at 9 participating public health centers were provided with customized health care services for 24 weeks, and 15 performance indicators were analyzed to evaluate their effectiveness. Results: Health behavior indicators and health risk factors decreased before and after participation in the project, blood pressure control rate, hypertension and diabetes management rate, medication compliance, weight, BMI, BP, WC, FBG, and HDL-cholesterol improved(p<0.001). Service factors that influence the improvement of health behaviors included the number of activity monitor transmissions(p=0.049), confirmed concentrated consultations on physical activity(p=0.003) and nutrition(p=0.005), and the adherence to medication missions for hypertension(p=0.020). As for service factors influencing chronic disease management, the improvement in blood pressure regulation rate was due to the number of times the blood pressure monitor was linked(p=0.004), and the number of confirmed intensive consultations on physical activity(p=0.026), and nutrition(p=0.049); the improvement in hypertension control rate was due to the number of times the activity monitor and blood pressure monitor were linked(p<0.001), and the number of hypertension medication missions carried out (p=0.004); and the improvement in diabetes control rate was due to the number of times the blood pressure monitor(p=0.022) and blood sugar system were linked(p=0.017). Conclusion: Although this study has limitations as a comparative study before and after the service, it has proved that chronic disease management using ICT has a positive effect on improvement of health behavior indicator, reduction of health risk factors, hypertension, diabetes management index, weight, BMI, TG, BP, FBG improvement.

• Journal of Chest Surgery
• /
• v.39 no.8 s.265
• /
• pp.611-618
• /
• 2006

Background: There have been controversies whether mitral valvular surgery is necessary in the patients with moderate ischemic mitral regurgitation undergoing coronary artery bypass grafting. The purpose of this study is to evaluate the long term clinical results of patients with moderate ischemic mitral regurgitation. Material and Method: Between January 1992 and February 2005, 44 patients with moderate ischemic mitral regurgitation underwent coronary artery bypass grafting. Concomitant mitral valvular procedure was performed in 20 patients (group 1) and isolated coronary artery bypass grafting was performed in 24 patients (group 2). There were no significant difference between groups except cardiopulmonary bypass time (p<0.01). Postoperative follow up duration was $30.1{\pm}29.6$ months and last follow up echocardiographic examination was performed at $21.2{\pm}28.0$ months. Result: There was no difference in operative mortality between groups (group 1 vs group 2, 15.0% vs 8.3%, p=0.493). Grade of mitral regurgitation ${(0.81{\pm}0.91\;vs\;1.50{\pm}0.05,\;p=0.046)}$ and reduction in regurgitation grade ${(1.75{\pm}0.93\;vs\;0.70{\pm}1.26,\;p=0.009)}$ were different between two groups. But there were no significant differences in left ventricular ejection fraction ${(34.1{\pm}11.4%\;vs\;41.6{\pm}12.9%)}$, left ventricular end systolic volume ${(118.2{\pm}63.9\;ml%\;vs\;85.6{\pm}281\;ml)}$, New York Heart Association functional class ${(2.1{\pm}0.2\;vs\;2.4{\pm}1.2)}$ and 5 year survival rate ${(85{\pm}8%\;vs\;82{\pm}8%)}$. There was no risk factor for operative mortality and the only risk factor for late death was preoperative atrial fibrillation (p=0.042). There was no significant correlation between mitral valvular surgery and late death. Conclusion: Concomitant mitral valvular procedure in patients with moderate ischemic mitral regurgitation undergoing coronary artery bypass grafting had no significant positive effect on survival and ventricular function compared with isolated coronary artery bypass grafting. Prospective randomized study may be needed to evaluate the necessity of concomitant mitral procedure and to find more effective method for the improvement of ventricular function.

• Clinical and Experimental Pediatrics
• /
• v.46 no.12
• /
• pp.1253-1259
• /
• 2003

Backgroud : Seizures in the neonate are relatively common and their clinical features are different from those in children and adults. The study aimed to provide the clinical profiles of neonatal seizure in our hospital. Methods : A total of 41 newborns with seizures were enrolled in this study over a period of three years. They were evaluated with special reference to risk factors, neurologic examinations, laboratory data, neuroimaging studies, EEG findings, seizure types, response to treatment, and prognosis, etc. Results : The average age at onset of seizures was $6.1{\pm}4.6days$ and the majority of patients(42%) had multifocal clonic seizure and 24% had subtle seizure. Factors that are known to increase risk of neonatal seizures include abnormal delivery history, birth asphyxia, and electrolyte imbalance, etc. However, they remain obscure in about 20% of cases. More than 50 percent showed abnormal lesions on neuroimaging studies such as brain hemorrhage, periventricular leukomalacia, brain infarction, cortical dysplasia, hydrocephalus, etc. and 17 out of 32 patients showed abnormal electroencephalographic patterns. Phenobarbital was tried as a first line antiepileptic drug and phenytoin was added if it failed to control seizures. The treatments were terminated in the majority of patients during the hospital stay. The overall prognosis was relatively good except for those with abnormal EEG background or congenital central nervous system malformations. Conclusion : Neonatal seizures may permanently disrupt brain development. Better understanding of their clinical profiles and appropriate management may lead to a reduction in neurological disability in later childhood.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.4
• /
• pp.2159-2164
• /
• 2016

Background: A diagnosis of chronic myeloid leukemia (CML) is made on discovery of the presence of a Philadelphia (Ph) chromosome. The success of the treatment of this form of leukemia with tyrosine kinase inhibitor (TKI) is monitored by reduction of the Ph chromosome. Objective: To compare the role of conventional cytogenetic (CC) methods with a real time quantitative polymerase chain reaction (RQ-PCR) and fluorescence in situ hybridization (FISH) for diagnosis and treatment monitoring of CML patients. The secondary outcome was to analyze the treatment responses to TKI in CML patients. Materials and Methods: This was a retrospective study of CML patients who attended the Hematology clinic at Chiang Mai University Hospital from 2005-2010. Medical records were reviewed for demographic data, risk score, treatment response and the results of CC methods, FISH and RQ-PCR. Results: One hundred and twenty three cases were included in the study, 57.7% of whom were male with a mean age of 46.9 years. Most of the patients registered as intermediate to high risk on the Sokal score. At diagnosis, 121 patients were tested using the CC method and 118 (95.9%) were identified as positive. Five patients failed to be diagnosed by CC methods but were positive for BCR-ABL1 using the FISH method. Imatinib was the first-line treatment used in 120 patients (97.6%). In most patients (108 out of 122, 88.5%), a complete cytogenetic response (CCyR) was achieved after TKI therapy and in 86 patients (70.5%) CCyR was achieved long term by the CC method. Five out of the 35 analyzed patients in which CCyR was achieved by the CC method had a positive FISH result. Out of the 76 patients in which CCyR was achieved, RQ-PCR classified patients to only CCyR in 17 patients (22.4%) with a deeper major molecular response (MMR) in 4 patients (5.3%) and complete molecular response (CMR) in 55 patients (72.4%). In the case of initial therapy, CCyR was achieved in 95 patients (79.1%) who received imatinib and in both patients who received dasatinib (100%). For the second line treatment, nilotinib were used in 30 patients and in 19 of them (63.3%) CCyR was achieved. In half of the 6 patients (50%) who received dasatinib as second line or third line treatment CCyR was also achieved. Conclusions: CML patients had a good response to TKI treatment. FISH could be useful for diagnosis in cases where CC analysis failed to detect the Ph chromosome. RQ-PCR was helpful in detecting any residual disease and determining the depth of the treatment response at levels greater than the CC methods.

• The Journal of Korean Society for Radiation Therapy
• /
• v.30 no.1_2
• /
• pp.35-40
• /
• 2018

Purpose : The range of force differs from the size of proton energy used in our hospital. The compensator enables to change energy size based on distal thickness which also makes changes in dose rate. Therefore, the purpose of this study is to evaluate the effect of changing the thickness of compensator distal on dose range and beam on time. Subject and Methodology : Five low energy patients who have received proton therapy were selected as subjects for this study. Beam on was checked for the selected patients during the existing therapy. After then, the thickness of distal of compensator was increased by 2 cm up to 14 cm through proton therapy plan system(TPS) for comparative analysis. For the evaluation of dose range, the value of the target's conformity index(CI) and the maximum dose of rear side target's organ at risk(OAR) were compared. Furthermore, to evaluate the effect of therapy time, beam on time was compared by making compensator distal in each thickness. Result : The result of homogeneity index and conformity index of the increased compensator distal showed the same level in all patients. The comparison results of OAR of target rear side showed 7 cGy at spine cord of abdomen at maximum, 88 cGy at eyeball's RT lens, 391 cGy at RT lens of nasal cavity 51 cGy at trachea of the mediastinum, and 661 cGy at a small bowl of the pelvis. The comparison results of the beam on time showed a reduction from 126 seconds to 62 seconds for the abdomen, from 105 seconds to 37 seconds for the eyeball, from 187 seconds to 134 seconds for nasal cavity, from 100 seconds to 40 seconds for mediastinum, from 440 seconds to 118 seconds for the pelvis. Conclusion : The research result showed that as the distal thickness of compensator increased, the size of energy increased. In addition, beam on decreased due to the increase of dose rate. It is expected that the result would help reduce the treatment time and increase the convenience of patients if it is applied to liver patients who need respiratorygated therapy and pediatric patients. However, distal penumbra increased as the size energy increased. Therefore, in treating cases where OAR is in the vicinity of the target rear side, the influence of penumbra should be taken into account in adjusting thickness level of the compensator in proton therapy plan.

• Korea Science and Art Forum
• /
• v.37 no.4
• /
• pp.297-308
• /
• 2019

Air pollution due to the fine dust level updating every day, and the problem of indoor air pollution due to ventilation difficulties and indoor discharge pollutants is also serious. In order to improve the indoor air quality, the air purification effect using the plants is prominent. In this study was started to investigated the living environment of modern people, the risk of indoor air pollution and the improvement function of plants, and to activate plant application. The purpose of this study is to analyze the main functions and design status of domestic and overseas plant - related applications, and to understand the actual use of modern plant applications and to help them learn more convenient plant - related knowledge. Therefore, this paper attempted to establish a basis for suggesting a new plant application by conducting a survey on the health effects of indoor air pollution and user awareness of plant - related applications. The results and contents of the study are as follows. First, as a theoretical review, indoor air pollution is more dangerous to modern people who have a high proportion of indoor living time and adversely affects their health. In order to solve such a problem, it has been shown that air conditioning and stress reduction can be effectively achieved by placing plants in the indoor space. Second, the analysis of the previous study shows the risk of indoor air pollution and its adverse effects on health. In addition, I have been able to find some researches related to the improvement of the indoor air by using the air purifying plants, and I can see the improvement of the user's behavior through the development or improvement of the application. Third, as a result of the survey on the status of domestic and overseas plant application, the main function of the application having high installation number was watering notification, provision of basic information of plants, and most of the functions were plant discerment through cameras. Fourth, most of the survey respondents have either raised or raised plants. Those who have little experience with plant applications have also shown positive feedback in the future on the use of plant-related applications. In addition, due to social problems such as air pollution, air purification using plants and functional plants showed high interest. Based on these results, we propose the need for a multi-functional plant application that can improve the indoor air pollution and facilitate the provision of information related to it.