• Journal of The Korean Association For Science Education
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• v.43 no.6
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• pp.495-507
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• 2023

Teachers often encounter challenges in supporting students with question generation and the development of investigation plans in sensemaking activities. A primary challenge stems from the ambiguity surrounding how students apply their conceptual understandings in this process. This study aims to explore how students apply their conceptual understandings to generate questions and design investigation processes in a sensemaking activity. Two types of student group activities were identified and examined for comparison: One focused on designing a process to achieve the goal of sensemaking, and the other focused on following the step-by-step scientific inquiry procedures. The design of investigation process in each group was concretized with epistemic criteria used for evaluating the designs. The students' use of conceptual understandings in discussions around each was then examined. The findings reveal three epistemic criteria employed in generating questions and designing investigation processes. First, the students examined the interestingness of natural phenomena, using their conceptual understandings of the structure and function of entities within natural phenomena to identify a target phenomenon. This process involved verifying their existing knowledge to determine the need for new understanding. The second criterion was the feasibility of investigating specific variables with the given resources. Here, the students relied on their conceptual understandings of the structure and function of entities corresponding to each variable to assess whether each variable could be investigated. The third epistemic criterion involved examining whether the factors of target phenomena expressed in everyday terms could be translated into observable variables capable of explaining the phenomena. Conceptual understandings related to the function of entities were used to translate everyday expressions into observable variables and vice versa. The students' conceptual understanding of a comprehensive mechanism was used to connect the elements of the phenomenon and use the elements as potential factors to explain the target phenomenon. In the case where the students focused on carrying out step-by-step procedures, data collection feasibility was the sole epistemic criterion guiding the design. This study contributes to elucidating how the process of a sensemaking activity can be developed in the science classroom and developing conceptual supports for designing sensemaking activities that align with students' perspectives.

• Pediatric Infection and Vaccine
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• v.31 no.1
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• pp.12-24
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• 2024

The number of pediatric coronavirus disease 2019 (COVID-19) cases worldwide are increasing compared to the early phase of the pandemic, along with highly transmissible severe acute respiratory syndrome coronavirus variant and the increase in adult COVID-19 vaccination. We conducted a rapid systematic review and meta-analysis of published randomized clinical trials (RCTs) of the COVID-19 vaccines and the observational retrospective studies on adverse events after COVID-19 vaccination in adolescents. Seventeen studies were finally included in this systematic review. Meta-analysis showed that although vaccination in adolescents was significantly effective to prevent COVID-19 infection in retrospective studies (risk ratio [RR], 0.29; 95% confidence interval [CI], 0.22-0.37; I² =100%), however the effect of preventing COVID-19 infection was lower than in RCTs (RR, 0.05; 95% CI, 0.01-0.27). In five retrospective studies, the pooled estimated proportion of participants with myocarditis and/or pericarditis was 2.33 per 100,000 of the population (95% CI, 0.97-5.61 per 100,000). Sub-group analysis with sex and vaccine doses showed that male (5.35 per 100,000) and the second dose (9.71 per 100,000) had significantly higher incidence of myocarditis and/or pericarditis than female (1.09 per 100,000) and the first dose (1.61 per 100,000), respectively. Our study showed that mRNA COVID-19 vaccines in adolescent recipients were favorable and effective against COVID-19 in RCT as well as observational studies. The safety findings of BNT162b2 vaccine in adolescents were explored and we found the difference of safety according to sex and vaccine doses. The occurrence of adverse events after mRNA COVID-19 vaccination should be monitored.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.3
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• pp.169-175
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• 2016

Saccharin (o-benzoic sulfimide) is the first artificial and non-caloric sweetener that was first synthesized in 1879. In this study, we examined the biological activity of saccharin against various human cancer cell lines and human bone marrow-derived mesenchymal stem cells. A viability assay based on the conversion of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was performed to test for the cytotoxicity of saccharin about the four human cancer cell lines (H460, H157, A549 and SKOV3), one murine cancer cellline (Raw264.7), and MSCs. In order to find the differentially expressed gene in saccharin-treated MSCs against untreated MSCs, we performed annealing control primer (ACP)-based differential display reverse transcriptionp-olymerase chain reaction (DDRT-PCR). All tested cells were treated with saccharin at various concentrations (0.0, 4.8, 7.2, 9.6, 12.0, 14.4 mg/mL) for 48 hr. The number of metabolically active cancer cells decreased when treated with the saccharin at various concentrations for 48 hr as compared with the untreated cells. The decrease in cell survival was more evident with increasing concentrations of saccharin. Moreover, novel candidate genes, which were differentially expressed in MSCs in response to saccharin, were identified in 16 bands on 2% agarose gel. This revealed 16-7 up-regulated and 9 down-regulated-differentially expressed genes indicated by arrows. One of these candidate genes was a FK506-binding protein gene. The functional roles of FK506 binding proteins, with respect to the activities of stem cell proliferation, were not characterized. Further studies are required to get a better understanding of FK506-binding proteins in its roles in increasing stem cell proliferative activities from using saccharin.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.123-131
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• 2009

Purpose: We tested a sample of nuclear medicine workers at Korean healthcare institutions for internal contamination with radioactive isotopes, measuring concentrations and evaluating doses of individual exposure. Materials and Methods: The detection and measurement was performed on urine samples collected from 25 nuclear medicine workers at three large hospitals located in Seoul. Urine samples were collected once a week, 100~200 mL samples were gathered up to 6~10 times weekly. A high-purity germanium detector was used to measure gamma radiations in urine samples for the presence of radioactive isotopes. Based on the detection results, we estimated the amounts of intake and committed effective doses using IMBA software. In cases where committed effective doses could not be adequately evaluated with IMBA software, we estimated individual committed effective doses for radionuclides with a very short half life such as $^{99m}Tc$ and $^{123}I$, using the methods recommended by International Atomic Energy Agency. Results: Radionuclides detected through the analysis of urine samples included $^{99m}Tc$, $^{123}I$, $^{131}I$ and $^{201}Tl$, as well as $^{18}F$, a nuclide used in Positron Emission Tomography examinations. The committed effective doses, calculated based on the radionuclide concentrations in urine samples, ranged from 0 to 5 mSv, but were, in the majority of cases, less than 1 mSv. The committed effective dose exceeded 1 mSv in three of the samples, and all three were workers directly handling radioactive sources. No nurses were found to have a committed effective dose in excess of 1 mSv. Conclusions: To improve the accuracy of results, it may be necessary to conduct a long-term study, performed over a time span wide enough to allow the clear determination of the influence of seasonal factors. A larger sample should also help increase the reliability of results. However, as most Korean nuclear medicine workers are currently not necessary to monitored routinely for internal contamination with radionuclides. Notwithstanding, a continuous effort is recommended to reduce any unnecessary exposure to radioactive substances, even if in inconsequential amounts, by regularly surveying workplace environments and frequently monitoring atmospheric concentrations of radionuclides.

• Journal of Hospice and Palliative Care
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• v.11 no.1
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• pp.42-50
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• 2008

Purpose: Undertreatment of canter pain, especially due to the differences in the perception of pain between the patients and caregivers, is a well recognized problem. The purpose of this study were to determine if there exist differences in communication about pain intensity scores between patients and their family caregivers in Korea. Methods: A total of 127 patient-family caregiver dyads who have experienced canter pain participated in this study at a hospital in Seoul for six months. The data were obtained by fare to face interview with a structured questionnaire based on Brief Pain Inventory-Korean version and other previous researches. The clinical information for all patients was compiled by reviewing their medical records. Results: Patients' 'worst-pain for 24-hour' and 'right-now-pain' scores estimated by family caregivers were significantly higher than those by patient themselves. The degree of agreement between patients and family caregivers in the estimate of patients' 'worst-pain for 24-hour' intensity categories was 78.7% for 'severe pain', 40% for 'no pain', 27.5% for 'mild pain' and 22.9% for 'moderate pain'. In case of 'right-now-pain' intensity categories, the agreement was 50% for 'severe pain', 47.2% for mild pain, 46.3% for 'no pain', and 26.3% for 'moderate pain'. Conclusion: This study demonstrates that the degree of agreement between patients and family caregivers in the estimate of patients 'pain intensity categories was less than 50% except for 'severe pain'. The results indicate that Korean family caregivers tend to overestimate the canter pain intensity of their caring patients, especially, when a lancer patient has 'moderate' or 'mild pain'. Health Providers are advised to educate patient-family caregiver dyads to use a pain measurement scale to promote their agreement in pain Intensity stores. Further analyses and studies are needed to identify the factors and differences that influence their communication about pain intensity scores between patients and their family caregivers.

• Clinical and Experimental Pediatrics
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• v.48 no.10
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• pp.1102-1106
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• 2005

Purpose : The present study examined the etiology, management, and the difference of prognosis according to methodology of treatment in severe hyperbilirubinemia with total serum bilirubin levels of more than 25 mg/dL. Methods : Medical records of severe hyperbilirubiemia in newborns(serum level=25 mg/dL) admitted to the NICU of Samsung Medical Center between October 1994 and June 2004 were reviewed retrospectively. Infants were grouped according to methodology of treatment : Group I(phototherapy only, n=42), Group II(exchange transfusion, n=6). And In addition, we evaluated the etiology and the difference of prognosis. Results : A total of 48 documented cases of severe hyperbilirubinemia were identified. Birth weight was significantly lower in Group 2($2,852{\pm}1,085g$) compared to Group 1($3,137{\pm}437g$)(P<0.05). There were no significant differences in gestational age, sex, mode of delivery, inborn, age at presentation, and age at first examination and admission between the two study groups. Maximal bilirubin level was significantly higher in Group 2($45{\pm}16mg/dL$) compared to Group 1($29{\pm}6mg/dL$) (P<0.05). But there were no significant differences in neurologic outcome. Conclusion : Our study suggests that the present guidelines for managing hyperbilirubinemia in newborns should be effective but follow-up with the first postnatal week would be necessary for each detection and treatment in the newborn infants with high risk of severe hyperbilirubinemia.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.87-94
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• 2007

This study was carried out to know the effect of the oriental medicinal plants byproduct containing vitamin E and 0.1% antibiotics (T1) and the oriental medicinal plants byproduct containing vitamin E and the replacing antibiotics by 0.03% herb extracts (T2) and 0.1% aminolevulinic acid (T3) on production performance of finishing hog and its meat qualities. There were no significant differences in the daily weight gain, feed intake, and feed conversion rate values between all treatment groups. However, the T2 group tends to have a higher daily weight gain (g/day) than the other groups (p>0.05). The T2 group showed lower total-cholesterol and LDL-cholesterol contents (114.71 and 68.09 mg/dl, respectively) than the control in the blood serum (p<0.001), and all the treated groups of oriental medicinal plants byproduct and vitamin E increased HDL-cholesterol and decreased LDL-cholesterol contents in the blood serum. Content of vitamin E in muscles from the group T1, T2 and T3 (2.11, 2.21 and 2.18 mg $kg^{-1}$, respectively) showed higher levels than those of control. The presence of antibiotics (chlortetracycline) in hog loin meat were detected (0.08 ppm) in control sample. However, there was no antibiotic in other treated hog loin meats (T1, T2 and T3, respectively). The thiobarbituric acid reactive substances and volatile basic nitrogen values of the groups T2 (0.06 mg MA $kg^{-1}$ and 11.21 mg%, respectively) and T3 (0.05 mg MA $kg^{-1}$ and 8.23 mg%, respectively) were significantly (p<0.05) lower than that of control in loin meat. However, there was no significant difference between treated samples (T1, T2 and T3, respectively) and control in cooking loss and drip loss.

• Journal of the Korean Society of Radiology
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• v.5 no.3
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• pp.143-148
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• 2011

The purpose of this study was to examine the usefulness of SPIO contrast agent in Magnetic Resonance Cholangiopancreatography (MRCP) by performing a quantitative comparative analysis in patients undergoing MRCP for gallbladder stones with and without oral injection of SPIO (Superparamagnetic iron oxide) contrast agent. The subjects were 36 patients undergoing MRCP for suspected gallbladder stones between January 2009 and February 2010 and they were divided into halves to compare the two groups of with and without SPIO agent. For each subject in both the injected and non-injected group, T2-weighted images on a 1.5T MR scanner were obtained, using both the breath-holding and respiratory-triggered methods, respectively. The following regions were measured; for breath-hold T2-weighted images, the measurement regions were located at the central part of the gallbladder, and the areas 15 mm away from its center, toward the front and back, respectively, which were chosen to include surrounding tissues, while for respiratory-triggered T2-weighted images, at the central part of the gallbladder, and segment 5 and 6 of liver. In a quantitative analysis, average signal to noise ratio (SNR) in each of regions of interest (ROI) for each group were calculated and then average contrast to noise ratio (CNR) in each of ROI were obtained by using the SNR in the gallbladder as the basis to compare and analyze the values between the two groups. The CNR were higher for the injected group in those regions.

• Journal of Hospice and Palliative Care
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• v.14 no.2
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• pp.81-90
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• 2011

Purpose: This study is to understand how community members perceive past life recollection and preparation for death. Methods: Using a questionnaire, we surveyed 160 adult residents of one of the districts (gu) in Seoul, Korea. Descriptive statistics were used. Results: Participants chose their 30s and 40s as the most difficult time in their lives. The most painful experience was "an illness of a family member", followed by "trouble with a spouse", and "trouble with children". As for the most difficult social experience, "sense of loss in life" was ranked the highest. Personally, the happiest time was "accomplishment of a goal", while it was "happiness through children" in family relationship and "contribution to society through my career" in social life. As for the most regrettable experience, personally "having lived without purpose" was the highest, "not meeting my parents' expectation more" in family relationship; "not providing sufficient education" in relationship with children; "not having an occupation that I wanted" in work life, and "lack of social skills" in social life. More than 87% of the surveyed showed a positive attitude about the system of the do not resuscitate (DNS) order. For a situation where participants were supposed to have an incurable disease, "I want to be notified of the true condition" and "I want to write a will and advanced directives" ranked high, receiving more than 3.1 points out of 4. Conclusion: These results demonstrate the need for death education to provide people with an opportunity to accept their regrettable experiences in the past as part of their life. Also, this study suggests the importance of writing advanced directives for people to prepare for "death with dignity" how it can help their decision to be better respected.

• The Journal of the Korean Society for Microbiology
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• v.3 no.1
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• pp.35-41
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• 1968

An outbreak of typhoid fever in Samchunpo city was surveyed and the results were summarized as follows: 1. 638 of clinical cases were detected in 17 Dongs(districts) of the city of Samchunpo,(54,064), during the epidemic period from 1st September to the end of November, 1967. 2. The morbidity rate was 1,189 per 100,000 population;(1,300 female, and 1,060 male). 3. The highest peak was reached in the third week of September and a second peak appeared at the end of September 1967. 4. The mode of infection was suspected strongly as a water-borne and the source of infection as an old public well called Gal-Dae-Saim, since the causative agent was found in close public latrine and the contaminated sewage ditch witch was connected with the well. 5. All patients and carriers were treated at their home under the supervision of local medical authorities. 6. The Gal-Dae-Saim was closed immediately on 7th October, 1967 by the order of the mayor. 7. At the end of November, 1967 when the outbreak in Samchunpo was almost ended, another small epidemic occurred in Koseong county which bordered the eastern outskirt of the city. 8. During the survey, a strain of Shigella flexneri was isolated from the sewage located three meters from Gal-Dae-Saim and also from one case. 9. It was reported by the local health center in May, 1968, that no carrier had been detected in the survey made among the persons who had had typhoid fever in 1967. Also thereafter no cases of typhoid fever were reported through October, 1968.