• Title/Summary/Keyword: Damaging Factor

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IATROGENIC IMPACTION OF LOWER LEFT PERMANENT CANINE : CASE REPORT (하악 영구 견치의 의원성 매복에 대한 증례 보고)

  • Kim, Song-Yi;Choi, Sung-Chul;Choi, Yeong-Chul;Park, Jae-Hong
    • Journal of the korean academy of Pediatric Dentistry
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    • v.35 no.2
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    • pp.339-344
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    • 2008
  • When a delayed eruption of tooth is diagnosed, the causative factor should be detected before an establishment of treatment plan, if possible. Although a panoramic radiograph is enough to evaluate the position of tooth and the stage of tooth development, a 3-D Dental CT would be a powerful tool to reveal a spatial relationships between objects. The reported case showed a delayed eruption of lower left permanent canine and a mini-plate with screws adjacent to the impacted canine. Although the screws adjacent to the root of impacted tooth showed a close proximity, it was not presumed that these screws would interfere the eruption of the tooth. The impacted canine did not show any spontaneous eruption during observation. After the mini-plate and screws were removed, an orthodontic traction using elastic power chain was performed. The position of mini-plates and screws should be carefully designed to avoid damaging the tooth follicles or tooth roots in the jaw. Also the screws should be removed before an orthodontic traction to prevent damaging the root surface of impacted tooth.

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The Research of Condition for Mural Tomb in Goa-ri, Goryeong in Gaya period (대가야 시기 고령 고아리 벽화 고분의 보존 상태 연구)

  • Lee, Kyeong Min;Lee, Hwa Soo;Han, Kyeong Soon
    • Korean Journal of Heritage: History & Science
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    • v.48 no.4
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    • pp.44-61
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    • 2015
  • Mural tomb in Goa-ri(Goryeong) built in the 6th Century Gaya period investigated precisely by the scientific method. They were used to optical equipments for investigation and made a damage map according to the damaging types. The mortar layer was mostly exfoliated from the rest of the wall except for the burial chamber ceiling and corridor ceiling. Also painting layers rarely not observed. Most of the paintings were damaged except lotus painting in burial chamber ceiling. Various damage types that exfoliation, earthen dirt, film coating were found in murals. Damage factors of mural were the porous characteristics of mortar layer and the movement of moisture in the murals. They were caused physical damage such as crack, exfoliation. It was getting worse and causing to secondary damage like earthen dirt, film coating.

Incorporating ground motion effects into Sasaki and Tamura prediction equations of liquefaction-induced uplift of underground structures

  • Chou, Jui-Ching;Lin, Der-Guey
    • Geomechanics and Engineering
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    • v.22 no.1
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    • pp.25-33
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    • 2020
  • In metropolitan areas, the quantity and density of the underground structure increase rapidly in recent years. Even though most damage incidents of the underground structure were minor, there were still few incidents causing a great loss in lives and economy. Therefore, the safety evaluation of the underground structure becomes an important issue in the disaster prevention plan. Liquefaction induced uplift is one important factor damaging the underground structure. In order to perform a preliminary evaluation on the safety of the underground structure, simplified prediction equations were introduced to provide a first order estimation of the liquefaction induced uplift. From previous studies, the input motion is a major factor affecting the magnitude of the uplift. However, effects of the input motion were not studied and included in these equations in an appropriate and rational manner. In this article, a numerical simulation approach (FLAC program with UBCSAND model) is adopted to study effects of the input motion on the uplift. Numerical results show that the uplift and the Arias Intensity (Ia) are closely related. A simple modification procedure to include the input motion effects in the Sasaki and Tamura prediction equation is proposed in this article for engineering practices.

Experimental Study of Relation between Air exclusion & Quality of the Concrete (공기 침투성과 콘크리트 품질의 상관관계에 관한 실험적 연구)

  • 박성우;윤성훈
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.10a
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    • pp.685-691
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    • 2002
  • Air exclusion test which is the way to assess the quality of the concrete is a part destructive test for minor damaging and accurate measurement. it has been well known but the test process is complexed, so it has been well known in foreign country but it is not usable in our country. For this experiment, it analyze its special quality through the inspection for the factor which effect to the result or accuracy for the Air exclusion test, and it examine through the experiment for the Non destructive test and cylinder compressive test which is different from the air exclusion test. We suggest the suitable classified table for the domestic concrete condition through the comparative analysis against the overseas result that has been suggested before.

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Overview of Innate Immunity in Drosophila

  • Kim, Tae-Il;Kim, Young-Joon
    • BMB Reports
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    • v.38 no.2
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    • pp.121-127
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    • 2005
  • Drosophila protects itself from infection by microbial organisms by means of its pivotal defense, the so-called innate immunity system. This is its sole defense as it lacks an adaptive immunity system such as is found in mammals. The strong conservation of innate immunity systems in organisms from Drosophila to mammals, and the ease with which Drosophila can be manipulated genetically, makes this fly a good model system for investigating the mechanisms of virulence of a number of medically important pathogens. Potentially damaging endogenous and/or exogenous challenges sensed by specific receptors initiate signals via the Toll and/or Imd signaling pathways. These in turn activate the transcription factors Dorsal, Dorsal-related immune factor (Dif) and Relish, culminating in transcription of genes involved in the production of antimicrobial peptides, melanization, phagocytosis, and the cytoskeletal rearrangement required for appropriate responses. Clarifying the regulatory interactions between the various pathways involved is very important for understanding the specificity and termination mechanism of the immune response.

Strength Properies of Concrete Using Waste Slag Aggregates as the Products of Steel Industry (산업폐기물인 제강 슬래그쇄석을 이용한 콘크리트의 강도특성)

  • Lee, Bong-Hak;Kim, Tae-Kyung
    • Journal of Industrial Technology
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    • v.16
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    • pp.45-50
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    • 1996
  • An experimental study os performed to examine the feasibility of using wastes steel furnace slag construction materials and its utility as a replacement for the natural resources to prevent the economic loss was investigated. A half factorial exprements was performed with the variables of W/C ratio, S/A, Coarse aggrigate/Slag ratio and slump as a preliminary study for optimum mix design of concrete. The results show that the W/C ratio and Slump ratio are the most important factor to the concrete strength. The substitute of waste Slag up to 100% has little influence, saying that it can substitute the coarse aggregate without damaging the concrete properties.

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Investigation of Cumulative Trauma Disorders in Manual Tasks - Case Study at Osram Sylvania, Inc. - (장기간의 작업으로 인한 손상 누적성 장애에 관한 연구 -Osram Sylvania, Inc.의 사례 연구-)

  • ;Andris Freivalds
    • Journal of the Korean Society of Safety
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    • v.12 no.4
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    • pp.153-160
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    • 1997
  • The purpose of this paper is to present design recommendations intended to reduce the risk of cumulative trauma disorders(CTD) at the Osram Slvania, Inc. The CTD risk index score is a method which quantifies the risk factors to CTD incidence, namely extreme postures, high force elements, frequent damaging hand motions, and other miscellaneous factors. The risk index score quantified the jobs as a single composite value by weighting the scores for each risk factor. Jobs were prioritized for capital outlays in workstation redesign, and the factors of highest risk within each job could be identified. Three jobs which presented the greatest risk of CTD incidence were redesigned ergonomically.

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Decomposition of Biological Macromolecules by Plasma Generated with Helium and Oxygen

  • Kim Seong-Mi;Kim Jong-Il
    • Journal of Microbiology
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    • v.44 no.4
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    • pp.466-471
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    • 2006
  • In this study, we attempted to characterize the biomolecular effects of an atmospheric-pressure cold plasma (APCP) system which utilizes helium/oxygen $(He/O_2)$. APCP using $He/O_2$ generates a low level of UV while generating reactive oxygen radicals which probably serve as the primary factor in sterilization; these reactive oxygen radicals have the advantage of being capable to access the interiors of the structures of microbial cells. The damaging effects of plasma exposure on polypeptides, DNA, and enzyme proteins in the cell were assessed using biochemical methods.

Long-term Activation of c-Jun N-terminal Kinase through Receptor Interacting Protein is Associated with DNA Damage-induced Cell Death

  • Seok, Jeong-Ho;Park, Kyeong-Ah;Byun, Hee-Sun;Won, Min-Ho;Shin, Sang-Hee;Choi, Byung-Lyul;Lee, Hyun-Ji;Kim, Young-Rae;Hong, Jang-Hee;Park, Jong-Sun;Hur, Gang-Min
    • The Korean Journal of Physiology and Pharmacology
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    • v.12 no.4
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    • pp.185-191
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    • 2008
  • Activation of c-Jun N-terminal kinase (JNK), a member of the mitogen-activated protein kinase family, is an important cellular response that modulates the outcome of the cells which are exposed to the tumor necrosis factor (TNF) or the genotoxic stress including DNA damaging agents. Although it is known that JNK is activated in response to genotoxic stress, neither the pathways to transduce signals to activate JNK nor the primary sensors of the cells that trigger the stress response have been identified. Here, we report that the receptor interacting protein (RIP), a key adaptor protein of TNF signaling, was required to activate JNK in the cells treated with certain DNA damaging agents such as adriamycin (Adr) and 1-${\beta}$-D-arabinofuranosylcytosine (Ara-C) that cause slow and sustained activation, but it was not required when treated with N-methyl-N-nitro-N-nitrosoguanidine (MNNG) and short wavelength UV, which causes quick and transient activation. Our findings revealed that this sustained JNK activation was not mediated by the TNF (tumor necrosis factor) receptor signaling, but it required a functional ATM (ataxia telangiectasia) activity. In addition, JNK inhibitor SP-600125 significantly blocked the Adr-induced cell death, but it did not affect the cell death induced by MNNG. These findings suggest that the sustained activation of JNK mediated by RIP plays an important role in the DNA damage-induced cell death, and that the duration of JNK activation relays a different stress response to determine the cell fate.

Estimation for Dynamic Deformation of the Cushioning Materials of Packaging for the Pears by Shock and Vibration During Transportation (유통 중 진동충격에 의한 배 포장 완충재의 동적 변위 추정)

  • Jung, Hyun-Mo;Park, In-Sig;Kim, Man-Soo
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.11 no.1
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    • pp.17-24
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    • 2005
  • During handling unitized products, they are subjected to a variety environmental hazards. Shock and vibration hazards are generally considered the most damaging of the environmental hazards on a product, and it may encounter while passing through the distribution environment. A major cause of shock damage to products is drops during manual handling. The increasing use of unitization on pallets has been resulted in a reduction in the manual handling of products and with it a reduction in the shock hazards. This has caused and increasing interest in research focused on vibration caused damage. the use of pallets as a base for unitizing loads, aids in the mechanical handling, transportation and storage of products. Besides aiding in the handling, transportation and storage of products, a pallet also acts on and interface between the packaged goods and the distribution environment. The determination of the impact deformation of the cushioning materials such as tray cup (polymeric foam) and corrugated fiberboard pad must be carried out to design the proper packaging system providing adequate protection for the fruit, and to understand the complex interaction between the components of fruit when they relate to expected transportation vibration inputs. In this study, the theoretical analysis of impact deformation for cushioning materials by dynamic vibration. The impact deformations of SW and DW corrugated fiberboard pad in acceleration amplitudes of 0.25 G-rms and 0.5 G-rms that were usually generated in transport vehicles during distribution environments were very small compare with the thickness of corrugated fiberboard pad. The maximum of vibration acceleration level of tray cup by vibration impact was about 3.2 G-rms. The theoretical allowable acceleration (G-factor) of the pear was 0.7102 G-rms, and the maximum dynamic deformation estimated within G-factor was about 1 mm.

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