• 한국초등과학교육학회지:초등과학교육
• /
• 제31권3호
• /
• pp.386-397
• /
• 2012

The purpose of this study was to find a way to improve the science textbook graph through analyzing teachers' interpretation process with eye movement tracking when they try to read the science textbook graph. Participants in this project were 10 elementary school teachers while bar graphs, line graphs, pie charts in 2007 revision science textbooks were used as materials. SMI (SensoMotoric Instruments)' iView X TM RED 120 Hz was used in order to collect eye movement data. Although subjects paid attention to the title of the graph at first, the consequence of the eye fixation was changed by the composition of the graph in case of the rest of areas. In particular, the flow of visual attention and fixation time were affected by the form and configuration of the graph. The diversity of graph construction caused confusion in interpreting graphs; the manner of presenting title, the difference of background colors, size of characters, the name of X-axis and Y-axis. Out results showed that the conformation of graphs as well as the presentation of each factor should be composed in accordance with the educational purpose for helping users to easier understanding.

• 미생물학회지
• /
• 제24권3호
• /
• pp.211-220
• /
• 1986

Nitrogen fixation (nif) genes of Rhizobium leguminosarum were transferred to nif Klebsiella pneumoniae and E. coli by conjugation after partial heat induction of $RP_4$ :: Mu cts in Rhizobium $R^+$ transconjugant, and the hybrid plasmids in the transconjugant strains were isolated and characterized. In order to transfer the nif genes from Rhizobium, the hybrid plasmid $RP_4$ :: Mu cts was transferred by conjugation from E. coil to the symbiotic nitrogen fixer, R. leguminosarum. After stabillity test, the $RP_4$ :: Mu cts in Rhixobium $R^+$ transconjugant was subjected to partial heat induction by culturing it statically at $38^{\circ}C$ for 16 hours, and then conjugated with the nif defective mutant strains of K. pneumoniae or nif mutant strains of E. coli having whole nif gene plasmid. Recombinant strains of K. pneumoniae, which could grow in a N-free medium and exhibit the nitrogenase activity were selected. However, in the case of E. coli, they could grow well in a NA medium containing antibiotices, but hardly frow in a N-free medium. The hybrid plasmids in these transconjugal strains were isolated by gel electrophoresis and compared their molecular sizes.

• The Journal of Advanced Prosthodontics
• /
• 제6권6호
• /
• pp.491-497
• /
• 2014

PURPOSE. This study evaluated the influence of abutment materials on the stability of the implant-abutment joint in internal conical connection type implant systems. MATERIALS AND METHODS. Internal conical connection type implants, cement-retained abutments, and tungsten carbide-coated abutment screws were used. The abutments were fabricated with commercially pure grade 3 titanium (group T3), commercially pure grade 4 titanium (group T4), or Ti-6Al-4V (group TA) (n=5, each). In order to assess the amount of settlement after abutment fixation, a 30-Ncm tightening torque was applied, then the change in length before and after tightening the abutment screw was measured, and the preload exerted was recorded. The compressive bending strength was measured under the ISO14801 conditions. In order to determine whether there were significant changes in settlement, preload, and compressive bending strength before and after abutment fixation depending on abutment materials, one-way ANOVA and Tukey's HSD post-hoc test was performed. RESULTS. Group TA exhibited the smallest mean change in the combined length of the implant and abutment before and after fixation, and no difference was observed between groups T3 and T4 (P>.05). Group TA exhibited the highest preload and compressive bending strength values, followed by T4, then T3 (P<.001). CONCLUSION. The abutment material can influence the stability of the interface in internal conical connection type implant systems. The strength of the abutment material was inversely correlated with settlement, and positively correlated with compressive bending strength. Preload was inversely proportional to the frictional coefficient of the abutment material.

• 대한족부족관절학회지
• /
• 제19권3호
• /
• pp.97-101
• /
• 2015

Purpose: The purpose of this study was to analyze the clinical results of application of bioabsorbable screws in hallux valgus surgery using modified Mau osteotomy. Materials and Methods: We retrospectively reviewed medical records of 25 patients. Operations were performed between May 2013 and January 2014. We performed 33 modified Mau osteotomies and fixed using bioabsorbable screws. Mean age of patients was 52 years (range 19 to 71). Mean follow up duration was 13.2 months (range 12.3 to 18.9). The clinical evaluations included pain visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, and satisfaction score. Weight bearing anteroposterior radiographs were taken for measurement of hallux valgus angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (DMAA). All radiographs were evaluated in order to detect complications related to bioabsorbable screws such as osteolysis, cyst formation, and fixation failure. Results: The mean pre- and postoperative pain VAS scores were 4.0 and 1.7 (p<0.05). The mean AOFAS score improved from 52.6 to 82.8 (p<0.05). Preoperative HVA and IMA were 31.2 and 13.9, respectively. Postoperative HVA and IMA were 5.2 and 6.2 (p<0.05). The DMAA increased from 7.8 to 9.9 (p<0.05). There was one case of superficial wound infection and one loss of correction, and no case of osteolysis, cystic formation around the screw, or deep infection. All patients showed union without fixation failure. Conclusion: The clinical and radiological evaluation of this study demonstrates reliable results without fixation failure or allergic reaction. The use of bioabsorbable screw appears not to be inferior to metal screw fixation in hallux valgus surgery.

• Journal of Korean Neurosurgical Society
• /
• 제45권4호
• /
• pp.219-223
• /
• 2009

Objective : Functional magnetic resonance imaging (fMRI) is frequently used to localize language areas in a non-invasive manner. Various paradigms for presurgical localization of language areas have been developed, but a systematic quantitative evaluation of the efficiency of those paradigms has not been performed. In the present study, the authors analyzed different language paradigms to see which paradigm is most efficient in localizing frontal language areas. Methods : Five men and five women with no neurological deficits participated (mean age, 24 years) in this study. All volunteers were right-handed. Each subject performed 4 tasks, including fixation (Fix), sentence reading (SRI. pseudoword reading (PR), and word generation (WG). Fixation and pseudoword reading were used as contrasts. The functional area was defined as the area(s) with a t-value of more than 3.92 in fMRI with different tasks. To apply an anatomical constraint, we used a brain atlas mapping system, which is available in AFNI, to define the anatomical frontal language area. The numbers of voxels in overlapped area between anatomical and functional area were individually counted in the frontal expressive language area. Results : Of the various combinations, the word generation task was most effective in delineating the frontal expressive language area when fixation was used as a contrast (p<0.05). The sensitivity of this test for localizing Broca's area was 81 % and specificity was 70%. Conclusion : Word generation versus fixation could effectively and reliably delineate the frontal language area. A customized effective paradigm should be analyzed in order to evaluate various language functions.

• 한국안전학회지
• /
• 제32권5호
• /
• pp.41-46
• /
• 2017

The coefficient of derailment and the rate of wheel load reduction were used as the index of train running safety that was directly affected the train derailment safety. In aspects of track, the train running safety depends on the complex interaction between wheel and rail, and the track-vehicle conditions (i.e., the curvature, cant, track system, vehicle speed and the operation conditions, etc). In this study, the relationship between the train running safety and the track curvature and vehicle speed for direct fixation concrete tracks currently employed in Korean light rapid transit was assessed by performing field tests using actual vehicles running along the service lines. The measured dynamic wheel load, lateral wheel load and lateral displacement of rail head were measured for same train running on four tested tracks under real conditions, which included curved and tangent tracks placed on the tunnel and bridge, thus increasing the train speed by approximately maximum design speed of each test site. Therefore, the measured dynamic track response was applied to the running safety analysis in order to evaluate the coefficient of derailment, the rate of wheel load reduction and the track gauge widening at each test site, and compare with the corresponding Korean train running safety standard. As the results, the lateral track response of direct fixation concrete track appeared to increase with the decreased track curvature; therefore, it was inferred that the track curvature directly affected the train running safety.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제33권5호
• /
• pp.499-503
• /
• 2007

Introduction: In orthognathic surgery, internal fixation has been usually done with titanium plates and screws. Recently, Biodegradable plates and screws have been frequently used but the reports of long term results of postoperative stability are rare, especially after maxillary reposition in orthognathic surgery. Objective: In order to clarify the clinical utility of self-reinforced bioresorbable poly-70L/30DL-Lactide miniplates & screws in maxillary fixation after LeFort I osteotomy, this study examined the postsurgical changes in maxilla and complications of biodegradable plates and screws. Study design: Nineteen patients who had undergone maxillary internal fixation using biodegradable plates and screws were evaluated radiographically and clinically. A comparison study of the changes in maxilla position after surgery in all 19 patients was performed with 1-week, 1-month, 3-months, 6-months and/or 1-year postoperative lateral cephalograms by tracing. Complication of the biodegradable plates and screws was evaluated by follow-up roentgenograms and clinical observation. And one-way ANOVA test was used for statistical analysis. Results: The position of the maxillary bone was stable after surgery and was not changed significantly from 1 week to 1 year after operation. And we could not find any complication of biodegradable plates and screws. Conclusions: Internal fixation of the maxilla after LeFort I osteotomy using self-reinforced biodegradable plates and screws is a reliable method for maintaining postoperative position of the maxilla after LeFort I osteotomy.

• Nuclear Engineering and Technology
• /
• 제5권4호
• /
• pp.310-320
• /
• 1973

천연점토 광물의 이온 교환 흡착능은 비교적 낮지만, 여러가지 활성화법이 고찰되고 있음으로서 성능의 개선이 기대되고 있다. 그중에서도 교환흡착능이 크며, 많은 양이 산출되고 있는 국산 vermiculite의 Nacl 및 KCI 처리에 의한 Cs+ ion의 교환흡착 및 고착상태에 관하여 방사성 폐액 처리의 응용면에서 연구되었으며, 그 결과는 다음과 같다. (1) pH의 증가와 더불어 Cs+ ion의 제렴율도 증가하였다. (2) 약 $10^{-3}$M CsCl 용액중 에서 Cs+ ion의 제렴효율이 가장 높았다. (3) Na-vermiculite에 의한 Cs+ ion의 교환 흡착능이 K-vermiculite에 비해 양호하였다. (4) $H_2O$, CsCl, NaCl 및 KCl 용액에 의한 추출 실험에서 80% 정도의 Cesium이 vermiculite상에 고착되었다. 이상의 결과로 부티 국산 vermiculite도 Ca+ ion의 교환흡착에 대한 친화력이 크며, NaCl 처리에 의하여 그 성능을 크게 향상시킬 수 있고, 고 준위 방사성 폐액의 지하저장에서 오는 누출천상을 저지시키기 위한 외각 충진제로서도 그 효율성을 보여 주고 있다. 또한 X-ray 회절상에서 보여 준 바와 같이 인위적으로 NaCl 처리에 의하여 biotite를 vermiculite로 전환시킬 수 있다는 것을 암시하고 있다.

• Applied Biological Chemistry
• /
• 제11권
• /
• pp.29-33
• /
• 1969

1. $NADPH_2$산화효소존재하(酸化酵素存在下)에 있어서 Quinone에 의(依)한 $NADPH_2$의 산화(酸化)를 시험관내(試驗管內)에서 조사(調査)하였다. 그 결과(結果)를 $3{\times}10^{-5}M$.의 각종(各種) Quinone 류(類)로 $^{14}CO_2$고정(固定) 10분전급고정시험중(分前及固定試驗中) 처리(處理)한 Chlorella의 $^{11}CO_2$고정율(固定率)과 비교(比較)하였다. 2. 각종(各種) Quinone 류(類)의 $NADPH_2$ 산화속도(酸化速度)와 $^{14}CO_2$ 고정율(固定率)사이에는 밀접(密接)한 관계(關係)가 있음이 밝혀졌다. $NADPH_2$ 산화(酸化)와 $^{14}CO_2$ 고정(固定)에 대(對)한 Quinone의 영향(影響)은 그 세기가 다음 순서(順序)와 같다. Dichlone>06-K>NQ>BQ 3. Chlorella에 대(對)한 Quinone의 독성(毒性)은 NADPH를 식물체(植物體)에서 없앰으로서 $^{14}CO_2$ 고정(固定)을 방해(妨害)하여 세포(細胞)를 결과적(結果的)으로 죽이는 것이라고 생각이된다. 4. Chlorella의 아미노산(酸) 생합성(生合成)에 대(對)한 Quinone류(類)의 영향(影響)은 전반적(全般的)으로 이를 억제(抑制)하는 것이라 하겠다. 이것은 특(特)히 Dichlone에 있어서 현저(顯著)하다. 이 현상(現象)은 식물(植物)에 $NADPH_2$가 없어지고 $^{14}CO_2$고정(固定)이 조해(阻害)되기 때문일 것이다. 자당(蔗糖)의 생합성(生合成)은 영향(影響)을 받지않거나 오히려 자극(刺戟)을 받는데 그 이유(理由)는 불분명(不分明)하다.

• Clinics in Shoulder and Elbow
• /
• 제19권4호
• /
• pp.249-251
• /
• 2016

iepicondylar fracture of the humerus is very rare in adults. To date, there have been limited evidence of this injury in the English literature. We report a case of a 65-year-old female with a biepicondylar fracture of the left distal humerus without dislocation. Open reduction and internal fixation with K-wires, cannulated screw, and suture anchor were performed. We obtained stability of the elbow and a satisfactory functional outcome. Because this type of injury is associated with varus and valgus instability, operative reduction and fixation are essential in order to gain stability and early recovery of normal function.