• Steel and Composite Structures
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• 제24권3호
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• pp.277-285
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• 2017

Single-storey industrial buildings are one of the most often type of structures built among various skeletal framed steel constructions. These metallic buildings offer an exceptional opportunity to minimise the material employed, contributing to a more sustainable construction. In particular, the mansard portal frame is a typology made up of broken beams that involves different lengths and discontinuous slopes. This study aims the weight reduction of the standard mansard portal frame with design purposes by means of varying four parameters: the kink position, the eaves-apex slope, the span and the columns height. In this work, we suggest some guidelines that can improve the economical competitive capabilities of their structural design. In all the cases analysed, the joints of the portal frame are placed over the theoretical non-funicular shape to uniform loads. This allows reducing the bending moment and the shear force, but increasing the axial force. In addition, the performance of mansard and typical pitched portal frames submitted to the same boundary conditions is compared in terms of efficiency in the use of steel. In the large majority of the cases, mansard typologies are lighter than the common pitched frames and, hence, more economical.

• 대한골관절종양학회지
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• 제13권1호
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• pp.14-21
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• 2007

Bone is a common site for metastatic spread from many kinds of malignancies. The morbidity associated with this metastatic spread can be significant, including severe pain. When it comes to spinal metastasis, occupying nearly 40% of skeletal metastases, the risks of complications, such as vertebral body collapse, nerve root impingement, or spinal cord compression, are also significant. Because of the necessity of preserving the integrity of the spinal column and the proximity of critical structures, surgical treatment has limitations when durable local control is desired. Radiotherapy, therefore, is often used as an adjunct treatment or as a sole treatment. A considerable limitation of standard radiotherapy is the reported recurrence rate or ineffective palliation of pain, either clinically or symptomatically. This may be due to limited radiation doses to tumor itself because of the proximity of critical structures. CyberKnife is an image-guided robotic radiosurgical system. The image guidance system includes a kilovoltage X-ray imaging source and amorphous silica detectors. The radiation delivery device is a mobile X-band linear accelerator (6 MV) mounted on a robotic arm. Highly conformal fields and hypofractionated radiotherapy schedules are increasingly being used as a means to achieve biologic dose escalation for body tumors. Therefore, we can give much higher doses to the targeted tumor volume with minimizing doses to the surrounding critical structures, resulting in more effective local control and less severe side effects, compared to conventional fractionated radiotherapy. A description of this technology and a review of clinical applications to bone metastases are detailed herein.

• KCI Concrete Journal
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• 제12권2호
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• pp.55-72
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• 2000

This paper proposes a mechanical model to describe the load-deformation responses of the reinforced concrete plate members under service load state. An Analytical method is introduced on the basis of the rotating crack model which considers equilibrium, compatibility conditions, load-strain relationship of cracked member, and constitutive law for materials. The tension stiffening effect in reinforced concrete structures is taken into account by the average tensile stress-strain relationship from the load-strain relationship for the cracked member and the constitutive law for material. The strain compatibility is used to find out the crack direction because the crack direction is an unknown variable in the equilibrium and compatibility conditions. The proposed theory is verified by the numerous experimental data such as the crack direction, moment-steel strain relationship, moment-crack width relationship. The present paper can provide some basis for the provision of the definition of serviceability for plate structures of which reinforcements are deviated from the principal stresses, because the present code defines the serviceability by the deflection, crack control, vibration and fatigue basically for the skeletal members. The proposed theory is applicable to predict the service load state behavior of a variety of reinforced concrete plate structures such as skew slab bridges, the deck of skew girder bridges.

• 한국기계가공학회지
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• 제21권2호
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• pp.79-86
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• 2022

Numerous fabrication techniques have been used to mimic cylindrical natural tissues, such as blood vessels, tendons, ligaments, and skeletal muscles. However, most processes have limitations in achieving the biomimetic properties of multilayered and porous architectures. In this study, to embrace both features, a novel self-assembly method was proposed using electrospun microfibrous sheets. A bilayer microfibrous structure, comprising two sheets with different internal stresses, was fabricated by electrospinning a polycaprolactone (PCL) sheet on a uniaxially stretched thermoplastic polyurethane (TPU) sheet. Then, by removing the stretching tension, the sheet was rolled into a hollow cylindrical structure with a specific internal diameter. The internal diameter could be quantitatively controlled by adjusting the thickness of the PCL sheet against that of the TPU sheet. Through this self-assembly method, biomimetic cylindrical structures with multilayer and porous features can be manufactured in a stable and controllable manner. Therefore, the resulting structures may be applied to various tissue engineering scaffolds, especially vascular and connective tissues.

• Asian-Australasian Journal of Animal Sciences
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• 제30권10호
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• pp.1471-1477
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• 2017

Objective: Since athletic performance is a most importance trait in horses, most research focused on physiological and physical studies of horse athletic abilities. In contrast, the molecular analysis as well as the regulatory pathway studies remain insufficient for evaluation and prediction of horse athletic abilities. In our previous study, we identified AXL receptor tyrosine kinase (AXL) gene which was expressed as alternative spliced isoforms in skeletal muscle during exercise. In the present study, we validated two AXL alternative splicing transcripts (named as AXLa for long form and AXLb for short form) in equine skeletal muscle to gain insight(s) into the role of each alternative transcript during exercise. Methods: We validated two isoforms of AXL transcripts in horse tissues by reverse transcriptase polymerase chain reaction (RT-PCR), and then cloned the transcripts to confirm the alternative locus and its sequences. Additionally, we examined the expression patterns of AXLa and AXLb transcripts in horse tissues by quantitative RT-PCR (qRT-PCR). Results: Both of AXLa and AXLb transcripts were expressed in horse skeletal muscle and the expression levels were significantly increased after exercise. The sequencing analysis showed that there was an alternative splicing event at exon 11 between AXLa and AXLb transcripts. 3-dimentional (3D) prediction of the alternative protein structures revealed that the structural distance of the connective region between fibronectin type 3 (FN3) and immunoglobin (Ig) domain was different between two alternative isoforms. Conclusion: It is assumed that the expression patterns of AXLa and AXLb transcripts would be involved in regulation of exercise-induced stress in horse muscle possibly through an $NF-{\kappa}B$ signaling pathway. Further study is necessary to uncover biological function(s) and significance of the alternative splicing isoforms in race horse skeletal muscle.

• 생명과학회지
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• 제18권2호
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• pp.264-272
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• 2008

풀망둑(Acanthogobius hasta) 조직의 젖산탈수소효소(EC 1.1.1.27 Lactate dehydrogenase, LDH) 동위 효소의 특성을 생화학적, 면역화학적 및 역학적 방법에 의해 연구하였다. 풀망둑 골격근과 눈 조직의 젖산탈수소효소 활성이 65.30과 53.25 units였고, 심장과 간 조직에서는 낮게 나타났다. 골격근 조직의 LDH/CS는 22.29로 가장 높고, LDH 특이활성도는 뇌 56.45, 눈 38.04 및 골격근 11.04 units/mg였다. 각 조직에 대해 $A_4,\;B_4$, eye-specific $C_4$, 및 liver-specific $C_4$에 대한 항혈청으로 면역 침강 반응시킨 후 Polyacrylamide gel 전기영동 하였다. 골격근, 뇌 및 눈 조직에서 $A_4$ 동위효소가 우세하게 확인되었고, 심장에서는 $A_4$ 동위효소가 확인되었다. 또한 양극의 eye-specific t와 음극의 liver-specific $C_4$가 한 종에서 함께 발현되었으며, 눈 조직의 eye-specific $C_4$는 활성이 크고 간 조직의 liver-Specific $C_4$의 활성은 낮게 나타났다. 결과 $A_4$와 $C_4,\;A_4$와 $B_4$ 및 eye-specific $C_4$와 liver-specific $C_4$의 분자구조의 일부가 서로 유사하지만 $B_4$와 $C_4$의 구조는 서로 다른 것으로 나타났으므로 하부단위체 A는 보존적이고 하부단위체 B는 하부단위체 A보다 빠르게 진화된 것으로 사료된다. 골격근 조직의 LDH $A_4$ 동위효소는 affinity chromatography에서 $NAD^+$를 함유한 buffer를 유입한 후 용출된 분획에서 정제되었고, eye-specific $C_4$ 동위효소는 $A_4$ 분획에 이어 용출되었으므로 eye-specific $C_4$가 $A_4$의 분자 구조와 유사한 것으로 보인다. 그리고 LDH에 대한 피루브산의 저해 실험 결과 35.22-43.47% 의 활성이 남았고, $Km_{pyr}$은 0.080-0.098 mM이고 골격근과 눈조직의 Vmax은 153.85와 35.09 units였다. 또한 $B_4$ 동위효소가 열에 대해 가장 안정하였고 $C_4$는 $A_4$보다 안정하였으며, 최적 pH는 6.5로 나타났다. 본 실험 결과 풀망둑은 저 산소 환경조건에 적응되어져 조직들의 동위효소들이 $A_4$와 $B_4$ 동위효소 사이의 특성을 나타냈고, 골격근과 눈 조직에서 피루브산에 대한 LDH의 친화력이 상당히 크므로 LDH가 혐기적 조건에서 효율적으로 기능을 하는 것으로 사료된다.

• 대한치과교정학회지
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• 제21권2호
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• pp.447-455
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• 1991

This research was carried out in order to study the effects of Rapid Maxillary Expansion on maxilla and it's surrounding skeletal structures. The sample for this study consists of 14 patients who were in retention period after rapid maxillary expansion. Following results were obtained after performing comparative analysis of cephalograms taken before and after rapid maxillary expansion. 1. In almost every cases, inferior displacement of palatal planes with concurrent changes in their inclination were observed. 2. Changes in the inclination of palatal plane can be categorized into inferiorty inclined group, superiorly inclined group and constant group in relation to the states before rapid masillary expansion. 3. Decrease in < Se-FMN/PMV and increase in < Se-FMN-A were evident in the superiorly inclined group and vice versa for the inferiorly inclined group.

• 한국동물학회지
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• 제33권4호
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• pp.402-410
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• 1990

한국산 P. cantonensis의 골격 특징을 조사하기 위하여 같은 망둑어과 어류에 해당되는 Tridentiger obscurus, Synechogobius hasta 및 Odontogobius platycephala등의 골격들과 비교 검토한 결과, 새조골이 5개이고, 상미축골이 2개이며, hypomeral이 존재하는 점은 서로 일치하였으나, 뇌두개를 구성하는 골격들이 융합되었고, 익상골이 사각형이면서 방형골과 떨어져 있으며, 3개의 사출골은 융합하고, hypomeral이 늑골에 100% 부착하며, 준하미축골이 매우 퇴축되었으며, 또 치골과 관절골 사이의 관절이 잘 움직이고, 훙대와 요대의 관절과 이들의 지느러미 기부에 근육이 발달된 점 등으로 본 P. cantonensis에서만 독특하게 나타나고 있어 본 종은 망둑어과 어류 중에서도 계통분류학적으로 매우 특이한 분류군으로 사료되었다.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of the Pharmaceutical Society of Korea
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• pp.90-94
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• 2001

Wondonins A and B, aromatic alkaloids of an unprecedented skeletal class have been isolated form and association of the sponges Poecillastra wondoensis and Jaspis sp. In addition, four novel bromotyrosine-derived metabolites, psammaplins $A_1$ and $A_2$, aplysinellins A and B, have been isolated from the tropical sponge Aplysinella rhax. The structures of these compounds have been determined on the basis of combined chemical and spectral analyses. The new compounds exhibited significant cytotoxicity and antiangiogenic activity as well as inhibitory activities against farnesyl protein transferase and leucine aminopeptidase. In addition to these compounds, several bioactive metabolites have been isolated from sponges of Korean and tropical waters.

• Animal Systematics, Evolution and Diversity
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• 제32권1호
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• pp.38-43
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• 2016

Dendrophyllia compressa Ogawa and Takahashi, 1995 is newly reported from Korea. The specimen was collected off Seogwipo, Jeju-do, Korea in 1969. It is described herein based on the morphological characters of the skeletal structures. Dendrophyllia compressa is characterized by its small and bushy growth form with branches, vertical growth direction, small calicular diameter, compressed calice, Pourtalès Plan with vertical septal inner edges, flat and spongy columella, exserted septal upper margins, and epitheca. Dendrophyllia compressa has been synonymized with Cladopsammia eguchii . However, the former species differs from the latter species in its growth form, growth direction, colony size, corallite size, and corallite shape.