• Steel and Composite Structures
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• 제38권5호
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• pp.547-562
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• 2021

This paper aims to explore the mechanical behavior and moment-rotation model of blind bolted joints between concrete-filled double skin steel tubular columns and steel-concrete composite beams. For this type of joint, the inner tube and sandwiched concrete were additionally identified as basic components compared with CFST blind bolted joint. A modified moment-rotation model for this type of connection was developed, of which the compatibility condition and mechanical equilibrium were employed to determine the internal forces of basic components and neutral axis. Following this, load transfer mechanism among the inner tube, sandwiched concrete and outer tube was discussed to assert the action area of the components. Subsequently, assembly processes of basic coefficients in terms of their stiffness and resistances based on the component method by simplifying them as assemblages of springs in series or in parallel. Finally, an experimental investigation on four substructure joints with CFDST columns for validation purposes was carried out to capture the connection details. The predicted results derived from the mechanical models coincided well with the experimental results. It is demonstrated that the proposed mechanical model is capable of evaluating the complete moment-rotation relationships of blind bolted CFDST column composite connections.

• 대한두경부종양학회지
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• 제37권2호
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• pp.97-100
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• 2021

Pilomatricoma(or calcifying epithelioma) is a not common benign solitary tumor originated from outer root sheath cell of hair follicle or hair follicle of sebaceous glands. The tumor usually presents as an asymptomatic, hard, superficial located, and skin colored to reddish blue cutaneous mass. Most of the tumors are less than 10mm in diameter and adherent to the skin. Recently, 48-year-old man presented with cheek mass. The tumor was 2.6cm sized and located at the subcutaneous layer of cheek on CT scan. The tumor was clearly removed via transoral approach with buccal incision leaving no wound on face. The mass was confirmed as pilomatricoma on pathologic examination. Herein, we report our experience with literature review.

• Wind and Structures
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• 제35권3호
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• pp.213-227
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• 2022

The design of a building is a complex process that encompasses different fields: one of the most relevant is nowadays the energetic one, which has led to the introduction of new typologies of building envelopes. Among them, the Permeable Double Skin Façades (PDSF) are capable to reduce the solar impact and so to improve the energetic performances of the building. However, the aerodynamic characterization of a building with a PDSF is still little investigated in the current literature. The present paper proposes an experimental study to highlight the modifications induced by the outer porous façade in the aerodynamics of a building. A dedicated wind tunnel study is conducted on a rigid model of a prismatic high-rise building, where different façade configurations are tested. Specifically, the single-layer façade is compared to two PDSFs, the former realized with perforated metal and the latter with expanded metal. Outcomes of the tests allow estimating the cladding loads for all the configurations, quantifying the shielding effects ascribable to the porous layers that are translated in a significant reduction of the design pressure that could be up to 50%. Moreover, the impact of the PDSFs on the vortex shedding is investigated, suggesting the capability of the façade to suppress the generation of synchronised vortices and so mitigate the structural response of the building.

• 동의생리병리학회지
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• 제25권3호
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• pp.496-502
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• 2011

The present study was undertaken to investigate the effect of bee venom acupuncture therapy on the hair follicle growth by macroscopic, microscopic and immunohistochemical observation of skin 10 and 17 days after treatment. The results were as follows : Macroscopic hair follicle growth of 0.2 ml S.B.V. acupuncture treated group was more prominent than those of 0.1 ml S.B.V. acupuncture treated group and control group. Microscopic observation indicated that the hair follicle growth of control group reached anagen phase IV of hair growing cycle, and that of 0.1 ml and 0.2 ml S.B.V. acupuncture treated groups reached anagen phase VI and catagen, respectively. Immunohistochemical observations of the expression of various cytokines, enzymes and receptors in association with hair follicle cycle after local treatment of S.B.V. acupuncture therapy are as follows: Expression of fibroblast growth factor was more intense in epidermis and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of 0.1 ml S.B.V. acupuncture treated group and control group. Expression of epidermal growth factor was more intense in bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of 0.1 ml S.B.V. acupuncture treated group and control group. Expression of c-kit receptor was more intense in epidermis, bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of control group. Expression of vascular endothelial growth factor was more intense in epidermis, bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than that of control group. Expression of protein kinase C-${\alpha}$ was more intense in epidermis, bulge and outer root sheath in 0.2 ml S.B.V. acupuncture treated group than control group. It is concluded that bee venom acupuncture therapy promoted the expression of various cytokines, enzymes and receptors related to the hair growth cycle for hair growth. This findings indicates that bee venom acupuncture therapy is applicable to the treatment of hair loss.

• 대한화장품학회지
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• 제41권4호
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• pp.341-350
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• 2015

피부는 외부 유해물질로부터 내부기관을 보호하는 장벽기능을 하는 대표적인 기관으로 자외선(ultraviolet radiation, UV), 중금속, 각종 산화 물질들과 같은 외부의 위협에 항상 노출되어 있어 손상을 받기 쉽다. 특히 자외선 B (UVB)는 진피의 상부까지 도달하여 화상이나 홍반과 같은 염증반응을 일으키며 멜라닌 생성을 촉진시켜 색소 침착을 유발한다. 지나친 자외선 B의 피부세포로의 유입은 각질세포 및 진피 섬유아세포의 DNA손상을 야기하고, 세포외기질의 합성을 방해하여 피부탄력감소, 주름생성, 진피 결합조직의 손상과 함께 피부장벽을 붕괴시켜 노화를 일으키며, 장기간 노출 시 심각한 피부 병변으로 이어져 피부세포 사멸 및 종양의 발생으로까지 이어진다. Haloarcula vallismortis는 사해로부터 분리 동정한 미생물로 호염성 고생물의 생장적 특징은 아직 자세히 연구된 바는 없다. 대게 10% 이상의 염도에서 자라는데 실제 생장염도는 평균 20 ~ 25% 염도에서 자란다. 염도가 높은 호수나 염전에서 주로 발견되기 때문에 강한 햇빛에 대한 방어기작이 존재한다. 그중 하나로 다른 ATP를 생성하기 위한 bacteriorhodopsin외에 halorhodopsin이라는 색소를 이용, 광자(photon)를 흡수하고 염화이온 채널을 개방시켜 생기는 전위차를 이용해 추가로 에너지를 생산한다. 또 carotenoid 색소로 인해 농도가 높을시 분홍색 또는 빨간색을 띄는 특징이 있는데 이것이 강한 자외선에 대한 방어기작을 할 것이라고 여겨진다. 본 연구는 호염성 고세균이 자외선을 에너지 소스로 이용하는 특성을 이용하여 자외선으로부터 피부를 방어하는 방법을 개발하고자 이들의 피부각질세포에서 자외선에 의한 항염 효과 및 DNA 손상 방어 효과를 확인하였다. 그리고 이들을 천연 자외선 차단제의 소재로서 사용할 수 있음을 확인하였다.

• 동의생리병리학회지
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• 제22권4호
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• pp.778-790
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• 2008

This experiment investigated the effect of mixed extracts obtained from Mylabris phalerata Pall. and Drynariae Rhizoma on hair growth activity of the normal and spontaneous alopecia areata model of C57BL/6N mice for 16 days. First, we examined morphological regrowth of hair in normal and spontaneous alopecia model of C57BL/6N mice. Second, we examined immunoreactive density of vascular endothelial growth factor(VEGF), c-kit and protein kinase $C-{\alpha}(PKC-{\alpha})$ in skin of normal C57BL/6N mice by immunohistochemical methods. Third, we investigated expression of $TGF-{\beta}$, prolactin and placenta lactogen after topical application of mixed extracts of Mylabris phalerata Pall. and Drynariae Rhizoma to skin by RT-PCR. The results were as follows: Hair growth effect from middle and high concentration of mixed extracts of Mylabris phalerata Pall. and Drynariae Rhizoma was observed in 80% of normal mice in whose hair had been clipped in 15th days. Hair growth effect of all concentrations of mixed extracts of Mylabris phalerata Pall. and Drynariae Rhizoma was observed in 100% of spontaneous alopecia model of C57BL/6N mice in 15th days. Immunoreactive density of VEGF, c-kit and $PKC-{\alpha}$ in skin of all concentrations of mixed extracts of Mylabris phalerata Pall. and Drynariae Rhizoma were strongly stained in epidermis, bulge, secondary hair germ cells and cutaneous trunci m. compare to control group in 10th day. In experimental III group, Immunoreactive density of VEGF, c-kit and $PKC-{\alpha}$ in skin were strongly stained in inner and outer root sheath of skin. The treatment of mixed extracts of Mylabris phalerata Pall. and Drynariae Rhizoma increased the expression of $TGF-{\beta}$, placenta lactogen and prolactin in the skin of normal C57BL/6N mice compared to control group. These experiments suggest that mixed extracts of Mylabris phalerata Pall. and Drynariae Rhizoma may stimulate the topical hair growth activity and it can be useful for treatment of alopecia areata.

• 터널과지하공간
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• 제12권4호
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• pp.277-283
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• 2002

본 연구는 안쪽축이 회전하고 바깥쪽 실린더는 정지해있는 반경비가0.52이고 30$^{\circ}$ 경사진 동심 환형관내의 헬리컬 유동 특성에 관한 것이다. 비뉴튼 유체인 UC 수용액과 벤토나이트 수용액을 사용하여 안쪽축이 0~400pm으로 회전할 때 축방향 유동을 완전히 발달시킨 후 축방향 압력손실값을 측정하였다. 또한, 헬리컬 유동의 가시화는 불안정한 파를 관찰하기 위해 수행되었다. 현재 연구 결과는 표면마찰계수에 대해 로스비순(Ro)와 레이놀즈수(Re)의 관계를 나타내었다. 또한, 그 결과들은 유동 불안정성 메카니즘의 존재를 보인다. 축회전수가 증가함에 따라 압력손실이 증가하지만, 그 증가폭은 천이 및 난류영역에서는 레이놀즈수가 증가할수록 감소하며, 회전의 영향으로 유동교란이 증진되어 천이가 촉진된다. 또, 이런 유동교란의 증진은 표면마찰계수값의 증가와 함께 임계 레이놀즈수(Re$_{c}$)를 작게 만든다.

• ALGAE
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• 제32권3호
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• pp.261-273
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• 2017

Fine dust (FD) particles have become a major contributor to air pollution causing detrimental effects on the respiratory system and skin. Although some studies have investigated the effects of FD on the respiratory system, their possible effects on the skin remain under-explored. We investigated the FD mediated inflammatory responses in keratinocytes, present in the outer layers of skin tissues and the transfer of inflammatory potential to macrophages. We further evaluated the anti-inflammatory effects of the polyphenolic derivative, diphlorethohydroxycarmalol (DPHC) isolated from Ishige okamurae against FD-induced inflammation. Size distribution of FD particles was analyzed by scanning electron microscopy. FD particles induced the production of cyclooxygenase-2, prostaglandin E2 ($PGE_2$), interleukin (IL)-$1{\beta}$, and IL-6 in HaCaT keratinocytes and the expression of nitric oxide (NO), inducible nitric oxide synthases (iNOS), $PGE_2$, tumor necrosis factor-${\alpha}$ expression in RAW 264.7 macrophages. Further, we evaluated the inflammatory potential of the culture medium of inflammation-induced HaCaT cells in RAW 264.7 macrophages and observed a marked increase in the expression of NO, iNOS, $PGE_2$, and proinflammatory cytokines. DPHC treatment markedly attenuated the inflammatory responses, indicating its effectiveness in suppressing a broad range of inflammatory responses. It also showed anti-inflammatory potential in in-vivo experiments using FD-stimulated zebrafish embryos by decreasing NO and reactive oxygen species production, while eventing cell death caused by inflammation.

• 한국수산과학회지
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• 제50권6호
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• pp.714-720
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• 2017

Exposure to ultraviolet (UV) radiation is associated with the development of adverse effects in skin. Among the three types of UV rays, UV-B causes the most damaging effects, inducing sunburn and penetrating the outer skin, resulting in DNA mutations and skin cancer. The objective of this study was to formulate a UV-protective film by incorporating Ecklonia cava extracts. Cells covered with the film were exposed to UV-B (50, 80, and $100mJ/cm^2$). To determine the protective effects of the film, we evaluated cell viability, intracellular ROS generation, and apoptosis. We found that all E. cava extracts absorbed UV light and exhibited protective effects against UV-B-induced photodamage. Among the protective films examined in this study, that incorporating an E. cava 70% ethanol extract (70EX) formed the most effective protection against UV-B in HaCaT cells. These findings suggest that the application of film containing E. cava extract could prevent UV-B-induced photodamage, and offer protection against the detrimental effects of UV radiation, thus maintaining physiological condition.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권5호
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• pp.440-453
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• 2005

Objectives : To develop a bioactive membrane for guided bone regeneration (GBR), the biocompatibility and bone regenerating capacity of the cellulose membrane obtained from the Ascidians squirt skin were evaluated. Materials and methods : After processing the pure cellulose membrane from the squirt skin, the morphological study, amino acid analysis and the immunoreactivity of the cellulose membrane were tested. Total eighteen male Spraque-Dawley rats (12 weeks, weighing 250 to 300g) were divided into two control (n=8) and another two experimental groups (n=10). In the first experimental group (n=5), the cellulose membrane was applicated to the 8.0 mm sized calvarial bone defect and the same sized defect was left without cellulose membrane in the first control group (n=4). In the another experimental group (n=5), the cellulose membrane was applicated to the same sized calvarial bone defect after femoral bone graft and the same sized defect with bone graft was left without cellulose membrane in the another control group (n=4). Each group was sacrificed after 6 weeks, the histological study with H&E and Masson trichrome stain was done, and immunohistochemical stainings of angiogenin and VEGF were also carried out. Results : The squirt skin cellulose showed the bio-inductive effect on the bone and mesenchymal tissues in the periosteum of rat calvarial bone. This phenomenon was found only in the inner surface of the cellulose membrane after 6 weeks contrast to the outer surface. Bone defect covered with the bioactive cellulose membrane showed significantly greater bone formation compared with control groups. Mesenchymal cells beneath the inner surface of the bioactive cellulose membrane were positive to the angiogenin and VEGF antibodies. Conclusion : We suppose that there still remains extremely little amount of peptide fragment derived from the basement membrane matrix proteins of squirt skin, which is a kind of anchoring protein composed of glycocalyx. This composition could prevent the adverse immunological hypersensitivity and also induce bioactive properties of cellulose membrane. These properties induced the effective angiogenesis with rapid osteogenesis beneath the inner surface of cellulose membrane, and so the possibilities of clinical application in dental field as a GBR material will be able to be suggested.