• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.2
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• pp.197-208
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• 2003

Objective：In this study, we hypothesized that deficit in processing rapid linguistic stimuli is at the heart of Reading Disability(RD) and deficit in response inhibition is at the heart of Attention Deficit/Hyperactivity(ADHD). We conducted experiments to identify the core cognitive characteristics of children either with RD or with ADHD or with both, using attentional tasks and phoneme differential tests. Method：In the study 1, 28 children with ADHD, 16 children with RD+ADHD were individually administered visual/auditory performance tests. Then, the differences of performance on attentional tasks between two groups were compared while IQs of two groups were controlled. In the study 2, 13 children with RD+ADHD/RD, 13 children with ADHD, and 13 normal children were administered computerized phoneme differential tests. Result：Visual attentional tasks did not distinguish an ADHD group from a RD+ADHD group. With auditory attentional tasks, however, the comorbid group showed significantly more difficulties, causing a large variance in reaction time. RD, RD+ADHD, and ADHD groups showed more errors in phoneme differential tests than a normal control group, and each group showed distinctive performance patterns. Discussion：An ADHD group had difficulty in response inhibition and sustained attention, and children who also had RD along with ADHD magnified the auditory attentional difficulties. Even though children with RD had more trouble with responding correctly to target stimuli, their responses were not significantly different from those of children with ADHD.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.1-10
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• 2010

Background: Bioprosthetic materials have been made using glutaraldehyde fixation of porcine or bovine pericardium during cardiovascular surgery. But these bioprostheses have the problems of calcification and mechanical failure. We determined changes in tensile strength and elasticity of pericardium after glutaraldehyde, solvent, decellularization and detoxification. Material and Method: Tissues were allocated to four groups: glutaraldehyde with and without solvent, decellularization, and detoxification. We studied tensile strength and strain on tissues. We measured the tensile strength of fresh pericardium stretched in six directions (with 5 mm width), and % strain, which we calculated from the breaking point when we pulled the pericardium in two directions. Result: Tensile strength was reduced when we used the usual concentrated glutaraldehyde fixation (n=83, $MPa=11.47{\pm}5.40$, p=0.006), but there was no change when we used solvent. Elasticity was increased after glutaraldehyde fixation (n=83, strain $(%)=24.55{\pm}9.81$, p=0.00), but there was no change after solvent. After decellularization of pericardium, the tensile strength was generally reduced. The decrease in tensile strength after concentrated glutaraldehyde fixation for a long time was significantly greater less than after concentrated solvent (p=0.01, p=0.00). After detoxification, the differences in strength and strain were not significant. Conclusion: After glutaraldehyde treatment of pericardium there is no loss in tensile strength (even though we did the glutaraldehyde, solvent and detoxification treatments LOGIC IS UNCLEAR). Also, these treatments had a tendency to increase elasticity. Although post-treatment decellularization led to a significant loss in strength, this effect could be attenuated using a low concentration of solvent or hypertonic solution.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.372-380
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• 2009

After supercritical water treatment of poplar wood meals (passed through 60 mesh) for 60s between 325 and $425^{\circ}C$ at the fixed pressure at $220{\pm}10atm$, some solid residues were present in the degradation products. They mainly consisted of chemically modified lignin and fibrous materials. Glucose and xylose were identified as main sugar components of fibrous materials, and the highest ratio of glucose/xylose was achieved at the highest reaction temperature. As reaction temperature was elevated, the portion of fibrous materials decreased in the solid residues, while lignin was further accumulated. The H : G : S ratio of lignin in solid residues was estimated by analytical pyrolysis. Irrespective of reaction temperatures, the H:G:S ratios were not significantly changed in the lignin in solid residues. Compared to poplar milled wood lignin (MWL), it was remarkable that H type monomers were further lowered, while portion of S type monomers increased. The amount of G type monomers were relative stable. In presence of HCl catalyst, lowering H type as well as enhancing S type was further distinguishable. According to the result of nitrobenzene oxidation (NBO), ca. 265 mg of vanillin and syringaldehyde was yielded from poplar MWL as main products. However, remarkably reduced amount of NBO products were determined from solid residues by raising operating temperature as well as by the addition of HCl catalyst. These results strongly indicate that $\beta$-O-4 linkage could be easily cleaved during supercritical water treatment, so that the lignins in the solid residues seem to be condensed phenol polymers, which are mainly formed by carbon-carbon linkages rather than $\beta$-O-4 linkage.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.375-395
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• 2006

Purpose: Lingual nerve (LN) damage may be caused by either tumor resection or injury such as wisdom tooth extraction, Although autologous nerve graft is sometimes used to repair the damaged nerve, it has the disadvantage of necessity of another operation for nerve harvesting. Moreover, the results of nerve grafting is not satisfactory. The nerve growth factor (NGF) is well-known to play a critical role in peripheral nerve regeneration and its local delivery to the injured nerve has been continuously tried to enhance nerve regeneration. However, its application has limitations like repeated administration due to short half life of 30 minutes and an in vivo delivery model must allow for direct and local delivery. The aim of this study was to construct a well-functioning $rhNGF-{\beta}$ adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with enhanced and extended secretion of hNGF from the injured nerve by injecting $rhNGF-{\beta}$ gene directly into crush-injured LN in rat model. Materials and Methods: $hNGF-{\beta}$ gene was prepared from fetal brain cDNA library and cloned into E1/E3 deleted adenoviral vector which contains green fluorescence protein (GFP) gene as a reporter. After large scale production and purification of $rhNGF-{\beta}$ adenovirus, transfection efficiency and its expression at various cells (primary cultured Schwann cells, HEK293 cells, Schwann cell lines, NIH3T3 and CRH cells) were evaluated by fluorescent microscopy, RT-PCR, ELISA, immunocytochemistry. Furthermore, the function of rhNGF-beta, which was secreted from various cells infected with $rhNGF-{\beta}$ adenovirus, was evaluated using neuritogenesis of PC-12 cells. For in vivo evaluation of efficacy of $rhNGF-{\beta}$ adenovirus, the LNs of 8-week old rats were exposed and crush-injured with a small hemostat for 10 seconds. After the injury, $rhNGF-{\beta}$ adenovirus($2{\mu}l,\;1.5{\times}10^{11}pfu$) or saline was administered into the crushed site in the experimental (n=24) and the control group (n=24), respectively. Sham operation of another group of rats (n=9) was performed without administration of either saline or adenovirus. The taste recovery and the change of fungiform papilla were studied at 1, 2, 3 and 4 weeks. Each of the 6 animals was tested with different solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) by two-bottle test paradigm and the number of papilla was counted using SEM picture of tongue dorsum. LN was explored at the same interval as taste study and evaluated electro-physiologically (peak voltage and nerve conduction velocity) and histomorphometrically (axon count, myelin thickness). Results: The recombinant adenovirus vector carrying $rhNGF-{\beta}$ was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. GFP expression was observed in 90% of $rhNGF-{\beta}$ adenovirus infected cells compared with uninfected cells. Total mRNA isolated from $rhNGF-{\beta}$ adenovirus infected cells showed strong RT-PCR band, however uninfected or LacZ recombinant adenovirus infected cells did not. NGF quantification by ELISA showed a maximal release of $18865.4{\pm}310.9pg/ml$ NGF at the 4th day and stably continued till 14 days by $rhNGF-{\beta}$ adenovirus infected Schwann cells. PC-12 cells exposed to media with $rhNGF-{\beta}$ adenovirus infected Schwann cell revealed at the same level of neurite-extension as the commercial NGF did. $rhNGF-{\beta}$ adenovirus injected experimental groups in comparison to the control group exhibited different taste preference ratio. Salty, sweet and sour taste preference ratio were significantly different after 2 weeks from the beginning of the experiment, which were similar to the sham group, but not to the control group.

• Journal of The Korean Association For Science Education
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• v.42 no.3
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• pp.311-324
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• 2022

This study analyzed the types of scientific emoticons made by science-gifted elementary school students and their perceptions on making scientific emoticons. To do this, 71 students from 4th to 6th graders of two gifted science education center in Seoul were selected. Scientific emoticons made by the students were analyzed according to the number and types. Their perceptions on making scientific emoticons were also analyzed through a questionnaire and group interviews. In the analyses for types of text in the scientific emoticons, 'word type' and 'sentence type' were made more than 'question and answer type'. And the majority of students made more 'pun using pronunciation type' and 'mixed type' than other types. They also made more 'graphic type' and 'animation type' than 'text type' in the images of the scientific emoticons. In the analyses for the information of the scientific emoticons, 'positive emotion type' and 'negative emotion type' of scientific emoticons were made evenly. The students made more 'new creation type' than 'partial correction type' and 'entire reconstruction type'. They also used scientific knowledge that preceded the knowledge of science curriculum in their grade level. The scientific knowledge of chemistry was used more than physics, biology, earth science, and combination field. 'Name utilization type' was more than 'characteristic utilization type' and 'principle utilization type'. Students had various positive perceptions in making scientific emoticons such as 'increase of scientific knowledge', 'increase of various higher-order thinking abilities', 'ease of explanation, use, memory, and understanding of scientific knowledge', 'increase of fun, enjoyment, and interest about science and science learning', and 'increase of opportunity to express emotions'. They were also aware of some limitations related to 'difficulties in the process of making scientific emoticons', 'lack of time', and 'limit that it may end just for fun'. Educational implications of these findings are discussed.

• Korean Journal of Materials Research
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• v.7 no.4
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• pp.347-353
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• 1997

BaTiO$_{3}$물질은 뛰어난 유전체로 널리 알려져 왔으며 특히 Heywang등이 제안한 PTCR특성은 이 물질의 응용범위를 세라믹 필터, 회로보호소자, 온도감지소자 및 저항가열장치 등으로 확대시켰다. 이러한 특성의 발현기구는 아직까지 밝혀지지 않은 상태이지만 제 특성을 향상시키기 위한 노력은 계속되어왔다. 특히 개발목적에 맞게 온도에 따른 정저항 특성(PTCR; Positive temperature constnat of resistivity phenomena)을 설계하려는 시도가 계속되어 왔으며 그 중에서도 페로브스카아트계의 2가와 4가의 양이온 자리를 등가나 원자가가 다른 양이온으로 치환하여 특성을 개선하려는 시도가 계속되어 왔다. 특히 $Ca^{2+}$나 Sr$^{2+}$는 $Ba^{2+}$자리를 치환할 수 있는 물질로 개별적인 첨가에 대한 연구는 많은 연구자들에 의해 진행된 상태이지만 최종적인 영향이나 해석에 대해서는 연구자들간에 이견이 많은 상태이다. 이번 실험에서는 BaTiO$_{3}$계에 합성한 (Ca, Sr)TiO$_{3}$를 Ca와 Sr의 상대적인 비를 변화시키면서 전체적인 첨가량을 변화시켜 그에 따른 전기적 특성 및 미세구조를 살펴보았다. (Ca, Sr)TiO$_{3}$의 첨가로 상온저항 및 PTCR특성을 변화시킬 수 있었으며 이를 통해 PTCR물질의 활용범위를 넓힐 수 있는 발판을 마련할 계기가 되었다. 특히 기존의 연구가 주로 개별적인 Ca나 Sr의 첨가에 의한 미세구조와 전기적 특성변화의 연구에 치중해 있었던 것과는 달리 Sr과 Ca을 함께 치환하여 상대적인 비가 특성에 더 중요한 영향을 끼치는 것을 확인하였으며 적절한 합성비를 선택하면 퀴리온도에서의 저항변화폭을 유지하면서 상온저항을 낮출 수 있음을 확인하였다.문했던 연구소인 Shanghai Research Center of Biotechnology, Shanghai Institute of Industrial Microbiology 및 Scientific Research Institute of Food and Fermentation Industry을 소개하고저 한다. 짧은 기간의 방문이라 주로 해당연구소의 자체소개 자료를 중심으로 방문하면서 느낀점을 기술하고저 한다.초염기성암 기원의 사문암이 열수변질작용을 받아 생성되었음을 명확하게 지시하며, 따라서 활석 광석내에 존재하는 녹니석은 활석의 근원 광물로서 녹니석편암 및 녹니석 편마암 매의 녹니석이 활석화되고 남은 잔존광물이 아니라, 주변암에 의해 성분상의 영향을 받은 열수와 사문암과의 변질교대작용에 의한 활석화과정 중에 주로 생성된 것으로 추정된다. 이러한 결과는 연구지역의 활석광상이 초염기성암의 사문암화 작용과 활석화 작용의 두 가지 변질작용에 의해 형성되어졌음을 알려준다.농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았다이 낮았으나 통계학적 의의는 없었다[10.0%(4/40) : 8.2%(20/244), p>0.05]. 결론: 비디오흉강경술에서 재발을 낮추기 위해 수술시 폐야 전체를 관찰하여 존재하는 폐기포를 놓치지 않는 것이 중요하며, 폐기포를 확인하지 못한 경우와 이차성 자연기흉에 대해서는 흉막유착술에 더 세심한 주의가 필요하다는 것을 확인하였다. 비디오흉강경수술은 통증이 적고, 입원기간이 짧고, 사회로의 복귀가 빠르며, 고위험군에 적용할 수 있고, 무엇보다도 미용상의 이점이 크다는 면에서 자연기흉에 대해 유용한 치료방법임에는 틀림이 없으나 개흉술에 비해 재발율이 높고 비용이 비싸다는 문제가 제기되고 있는 만큼 더 세심한 주의와 장기 추적관찰이 필요하리라 사료된다.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.660-665
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• 1999

Structure of water soluble chitosan (WSC) was confirmed by Fourier transform infrared spectrometer (FT-IR), X-ray diffractometer and thermal analyser. The viscosity average molecular weight of WSC ranged from $3.0{\times}10^{4}$ to $4.5{\times}10^{4}$. Using the WSC having viscosity average molecular weight of $3.0{\times}10^{4}$, the antimicrobacterial effects against microorganism and oral microorganism showed 81.7% and 80.6% for Staphyloccus aureus and Bacillus subtilis, respectively, while the anitmicrobacterial effect exhibited 100% and 73.8% against Streptococcus mutans and Streptococcus sanguis, respectively. Therefore it is concluded that WSC is more effective against oral microorganism that microorganism in terms of antimicrobacterial effects. WSC sample with the viscosity average molecular weight of $4.5{\times}10^{4}$ exhibited a half of the antimicrobacterial effect of the low MW sample, indicating that the WSC with low MW was better than that with high MW. Chitin and chitosan showed a drastic decrease of acidity from pH 7.0 to 4.9 after 8 minute incubation time and reached an equilibrium after that. WSC, however, restrained pH of the sample from lowering up to about 16 minutes of incubation and reached an equilibrium after that. WSC obviously showed a buffering effect against pH change.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.201-208
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• 2008

Statement of problem: A new implant impression technique which use abutments as impression coping, and use resin cement as a splinting material was described. Accuracy of this technique was compared with conventional closed tray and resin splinted open tray technique for a $15^{\circ}$ angled 3-implant model Material and methods: A dental stone master model with 3 linearly positioned implant analogue and a reference framework which was passively fitted to it were fabricated. The center analogue was perpendicular to the plane of model and the outer analogues had a $15^{\circ}$angulation forward or backward. 10 closed tray impressions, 10 resin splinted open tray impressions, 10 abutment-resin framework cementation impressions and 10 abutment-metal framework cementation impressions were made with additional silicone material and poured with dental stone. A light microscope with image processing was used to record the vertical gap dimension between reference framework and analogue of duplicated cast made with each 4 impression techniques. Statistical analysis used one-way ANOVA with post-hoc tests Tukey test of .05 level of significance Results: Significant difference in the vertical gap dimension was found between closed tray technique; 74.3 (${\pm}33.4$)${\mu}m$ and resin splinted open tray technique, and two other new technique. (P<.05) Abutment-metal framework cementation technique;42.5 (${\pm}11.9$)${\mu}m$ was significantly different from resin splinted open tray technique. (P<.05) Abutmentresin framework cementation technique;51.0 (${\pm}14.1$)${\mu}m$ did not differ significantly from resin splinted open tray technique;50.3 (${\pm}16.9$)${\mu}m$. (P>.05) Conclusion: Within limitations of this study, the accuracy of implant level impressions of resin splinted open tray technique was superior to that of closed tray technique. A new technique using abutment and metal framework cementation was more accurate than resin splinted open tray technique.

• Research in Plant Disease
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• v.29 no.4
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• pp.331-344
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• 2023

More than a year has passed after the 6th edition of 'List of Plant Diseases in Korea (LPDK)' was published in April 2022. The 6.1st edition (2023) of List of Plant Diseases in Korea was made by correcting errors found in the 6th edition of list and adding new diseases reported after the 6th edition. There were 397 corrections from the 6th edition, most of which were simple spelling errors or minor issues. However, 12 diseases were deleted due to duplication or unclear literature proof, and 2 diseases had their diseases' common names changed. We added 158 diseases that were reported before 2021 but not included in the 6th edition, or reported after the 6th edition. After all, 146 diseases were added to the 6,534 diseases in the 6th edition, resulting in a total of 6,680 diseases in the 6.1st edition. Thirty host taxa were also added, increasing the number from 1,390 in the 6th edition to 1,420 in the 6.1st edition. Pathogens were also added to 62 taxa, from 2,400 in the 6th edition, bringing the total to 2,462 taxa in the 6.1st edition. Ultimately, the 6.1st edition (2023) of 'The List of Plant Diseases in Korea' contains 6,680 diseases caused by pathogens of 2,462 taxa on 1,420 hosts. The 6.1st edition is not printed as a book, but is provided through the online 'List of Plant Diseases in Korea' (https://genebank. rda.go.kr/kplantdisease.do).

• Radiation Oncology Journal
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• v.25 no.1
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• pp.7-15
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• 2007

[ $\underline{Purpose}$ ]: To determine the patterns of evaluation and treatment in patients with breast cancer after mastectomy and treated with radiotherapy. A nationwide study was performed with the goal of improving radiotherapy treatment. $\underline{Materials\;and\;Methods}$: A web- based database system for the Korean Patterns of Care Study (PCS) for 6 common cancers was developed. Randomly selected records of 286 eligible patients treated between 1998 and 1999 from 17 hospitals were reviewed. $\underline{Results}$: The ages of the study patients ranged from 20 to 80 years (median age 44 years). The pathologic T stage by the AJCC was T1 in 9.7% of the cases, T2 in 59.2% of the cases, T3 in 25.6% of the cases, and T4 in 5.3% of the cases. For analysis of nodal involvement, N0 was 7.3%, N1 was 14%, N2 was 38.8%, and N3 was 38.5% of the cases. The AJCC stage was stage I in 0.7% of the cases, stage IIa in 3.8% of the cases, stage IIb in 9.8% of the cases, stage IIIa in 43% of the cases, stage IIIb in 2.8% of the cases, and IIIc in 38.5% of the cases. There were various sequences of chemotherapy and radiotherapy after mastectomy. Mastectomy and chemotherapy followed by radiotherapy was the most commonly performed sequence in 47% of the cases. Mastectomy, chemotherapy, and radiotherapy followed by additional chemotherapy was performed in 35% of the cases, and neoadjuvant chemoradiotherapy was performed in 12.5% of the cases. The radiotherapy volume was chest wall only in 5.6% of the cases. The volume was chest wall and supraclavicular fossa (SCL) in 20.3% of the cases; chest wall, SCL and internal mammary lymph node (IMN) in 27.6% of the cases; chest wall, SCL and posterior axillary lymph node in 25.9% of the cases; chest wall, SCL, IMN, and posterior axillary lymph node in 19.9% of the cases. Two patients received IMN only. The method of chest wall irradiation was tangential field in 57.3% of the cases and electron beam in 42% of the cases. A bolus for the chest wall was used in 54.8% of the tangential field cases and 52.5% of the electron beam cases. The radiation dose to the chest wall was $45{\sim}59.4\;Gy$ (median 50.4 Gy), to the SCL was $45{\sim}59.4\;Gy$ (median 50.4 Gy), and to the PAB was $4.8{\sim}38.8\;Gy$, (median 9 Gy) $\underline{Conclusion}$: Different and various treatment methods were used for radiotherapy of the breast cancer patients after mastectomy in each hospital. Most of treatment methods varied in the irradiation of the chest wall. A separate analysis for the details of radiotherapy planning also needs to be followed and the outcome of treatment is needed in order to evaluate the different processes.