• Title/Summary/Keyword: Fine lines

Search Result 158, Processing Time 0.025 seconds

Dosimetric Characteristics of Multileaf Collimator-based Intensity-modulated Arc Therapy for Stereotactic Radiosurgery (방사선수술 시 다엽 콜리메이터를 기초로 한 IMAT의 선량분포)

  • Yun, Sang-Mo;Kim, Sung-Kyu
    • Progress in Medical Physics
    • /
    • v.18 no.2
    • /
    • pp.93-97
    • /
    • 2007
  • This study was designed to evaluate radiosurgery technique using multiple noncoplanar arc therapy with intensity modulated fine MLC shaped photon beam. The stereotactic radiosurgery was performed with 6-MV X-ray beams from a Clinac 21EX LINAC (Varian, Palo Alto, CA, USA) with a MLC-120, which features a full $40{\times}40cm$ field and is the first MLC for general use that offers 0.5 cm resolution for high precision treatment of small and irregular fields. We used a single isocenter and five gantry-couch combinations with a set of intensity modulated arc therapy. We investigated dosimetric characteristics of 2 cm sized spherical target volume with film (X-OMAT V2 film, Kodak Inc, Rochester NY, USA) dosimetry within $25{\times}25cm$ acrylic phantom. A simulated single isocentric treatment using inversely Planned 3D radiotherapy planning system demonstrated the ability to conform the dose distribution to an spherical target volume. The 80% dose level was adequate to encompass the target volume in frontal, sagittal, and transverse planes, and the region between the 40% and 80% isodose lines was $4.0{\sim}4.5mm$ and comparable to the dose distribution of the Boston Arcs. We expect that our radiosurgery technique could be a treatment option for irregular-shaped large intracranial target.

  • PDF

A Lab-Made Wound Maker for Analysis of Cell Migration in a 96-Well Plate (세포 이동능력 분석을 위한 96-Well Plate 전용 Lab-Made Wound Maker)

  • Lee, Tae Bok;Kim, Hwa Ryoung;Park, Seo Young
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.52 no.1
    • /
    • pp.53-61
    • /
    • 2020
  • Cell migration is a central process for recovering from wounds triggered by physical distress besides embryogenesis and cancer metastasis. Wound healing assay is widely used as a fundamental research technique for investigation of two-dimensional cell migration in vitro. The most common approach for imitating physical wound in vitro is mechanical scratching on the surface of the confluent monolayer by using sharp materials. The iron metal pin with a suspension spring for fine adjustment of the orthogonal contact surface between the scratching point and the individual bottom of multi-well plate with planar curvatures were adopted for the creative invention of a 96-well plate wound maker. While classic tips drew diverse and zigzag scratching patterns on the confluent monolayer, our wound maker displayed synchronized linear wounds in the middle of each well of a 96-well plate that was seeded with several cell lines. Given that several types of multi-well plates commercially available are compatible with our lab-made wound maker for creating uniform scratches on the confluent monolayer for the collective cell migration in wound healing assay, it is certain that the application of this wound maker to the real-time wound healing assay in high content screening (HCS) is superior than utilization of typical polypropylene pipette tips.

Effects of the Ge Prearmophization Ion Implantation on Titanium Salicide Junctions (게르마늄 Prearmophization 이온주입을 이용한 티타늄 salicide 접합부 특성 개선)

  • Kim, Sam-Dong;Lee, Seong-Dae;Lee, Jin-Gu;Hwang, In-Seok;Park, Dae-Gyu
    • Korean Journal of Materials Research
    • /
    • v.10 no.12
    • /
    • pp.812-818
    • /
    • 2000
  • We studied the effects of Ge preamorphization (PAM) on 0.25$\mu\textrm{m}$ Ti-salicide junctions using comparative study with As PAM. For each PAM schemes, ion implantations are performed at a dose of 2E14 ion/$\textrm{cm}^2$ and at 20keV energy using $^{75}$ /As+and GeF4 ion sources. Ge PAM showed better sheet resistance and within- wafer uniformity than those of As PAM at 0.257m line width of n +/p-well junctions. This attributes to enhanced C54-silicidation reaction and strong (040) preferred orientation of the C54-silicide due to minimized As presence at n+ junctions. At p+ junctions, comparable performance was obtained in Rs reduction at fine lines from both As and Ge PAM schemes. Junction leakage current (JLC) revels are below ~1E-14 A/$\mu\textrm{m}^{2}$ at area patterns for all process conditions, whereas no degradation in JLC is shown under Ge PAM condition even at edge- intensive patterns. Smooth $TiSi_2$ interface is observed by cross- section TEM (X- TEM), which supports minimized silicide agglomeration due to Ge PAM and low level of JLC. Both junction break- down voltage (JBV) and contact resistances are satisfactory at all process conditions.

  • PDF

Down-regulation of Tyrosinase, MITF, TRP-1, and TRP-2 Expressions by Juniperus rigida Sieb. in Murine B16F10 Melanoma (멜라노마세포(B16F10)에서 노간주나무의 tyrosinase, MITF, TRP-1 및 TRP-2 발현 저해능)

  • Lee, Soo-Yeon;Jun, Hye-Ji;Lee, In-Chul;Lee, Jin-Young
    • Journal of Life Science
    • /
    • v.23 no.12
    • /
    • pp.1445-1453
    • /
    • 2013
  • Human skin is constantly exposed to ultraviolet (UV) radiation, polluted air, and chemical products. UV rays, in particular, will affect the skin in a variety of ways, including causing wrinkles, fine lines, rough skin, and xeroderma, thereby resulting in skin aging. This study aimed to investigate the whitening effects of Juniperus rigida Sieb., which is a cedar tree that is found throughout the world. The whitening efficacy that was measured by tyrosinase inhibition revealed 49.4% efficacy in water extract and 80.0% efficacy in ethanol extract. Among the B16F10 black cells, the effect of the ethanol extract was higher than the effect of the water extract in the restrain creation of melanin pigment, tyrosinase, microphthalmia-associated transcription factor (MITF), tyrosinase related protein-1 (TRP-1), and tyrosinase related protein-2 (TRP-2). Thus, the results of these studies demonstrated that the ethanol extract had greater efficacy than the water extract and Juniperus rigida Sieb. Ethanol extracts could be utilized as materials for functional cosmetics, such as whitening products.

Meaning of Basic Geometry Patterns to Ancient Koreans and Its Classification (고대 한국인이 선호한 기본도형의 의미와 유형)

  • Park, Seon-Hwa;Kim, Ji-Soo;Na, Young-Joo
    • Science of Emotion and Sensibility
    • /
    • v.22 no.2
    • /
    • pp.83-100
    • /
    • 2019
  • The purposes of this study are to identify the meaning of the geometrical patterns preferred by ancient Korean peoples and to classify them into some groups by their similarity. We investigated various patterns found on clothing and relics from GoJoseon to Goguryeo period, and utilized secondary sources such as history articles, Internet materials and photo and analyzed the associations of the varied patterns found in pottery, handicrafts, and clothing with the ancient cultures. We found the letters (ㅇ, ㅁ, and ㅅ of Korean alphabet, Hangul) preferred by ancestors who worshipped nature to identify the significations attached by them to particular patterns. The results confirm the following: first, the circle pattern indicated the sun, moon, stars in the sky, a bronze mirror, and a man's face. Circles and ovals were also observed to represent the individual souls of the clan or community. Second, square patterns symbolized the land and the patterns that signified the wellbeing of family and the country. Oblique rectangles were more frequently used as they represented a double use of the triangle, a shape that implied mystic power. Third, triangle symbolized regeneration, power, and humanity. While the Neolithic Age jade remnants of hair combs appear not to be irrelevant to the process of comb-shaped pottery production of the time, many fine comb-like lines may be found on bronze mirrors. Through its review of the glorious designs inherited from and established by ancient ancestors, the present research endeavor may help in identifying the spirits and traditions of Korean history.

Analysis on the Rainfall Driven Slope Failure Adjacent to a Railway : Flume Tests (강우로 인한 철도 연변사면의 활동분석 : 실내모형실험)

  • SaGong Myung;Kim Min-Seok;Kim Soo-Sam;Lee In-Yong
    • Journal of the Korean Geotechnical Society
    • /
    • v.22 no.5
    • /
    • pp.83-91
    • /
    • 2006
  • Recently, the intensive rainstorm possibly induced by global warming plays a key role on the instability of railway adjacent slopes. The instability of slopes results as covering and loss of railway lines induced by slided soil mass. According to the site investigation on the failed slopes triggered by rainfall, low types of slope failure were observed: shallow, intermediate, gully erosion, and soil-rock interface failures. The observation reveals the different characteristics of slope failure depending on the thickness of soil layer, morphological features of slope, etc. Based upon the observations, flume tests were conducted to analyze the sliding mechanism of each failure. The variables of flume test are soil layer thickness, rainfall intensity, and morphology of slope under the constant condition of the percentage of fine, initial soil moisture content, slope angle and compaction energy. Test results show that shallow failure was mostly observed from the surface of the slope and caused by the soil erosion; in addition, compared to the other types of failure, the occurrence of initial erosion is late, however, the development of erosion is fast. In gully erosion failure, the collected water from the water catchment area helps erosion of the upper soil layer and transfer of residual corestone, which impedes the erosion process once the upper soil layers are eroded and corestone are exposed. The soil-rock interface failure shows the most fast initial erosion process among the failure types. Interestingly, the common feature observed from the different types of failure was the occurrence of the initial deformation near the toe of slopes which implies the existence of surbsurface flow along the downslope direction.

Seasonal Variation of Surface Sediments in the Myeongsasipri Tidal Flat, Gochanggun, SW Korea (고창군 명사십리 조간대 표층 퇴적물의 계절 변화)

  • So, Kwang-Suk;Ryang, Woo-Hun;Kwon, Yi-Kyun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.14 no.3
    • /
    • pp.181-188
    • /
    • 2009
  • The macro tidal flat of the Gochanggun Myongsasipri, located on the southwestern coast of Korea, is studied in terms of seasonal variations of surface sediment and sedimentary environment. Surface sediments of 45 sites in the winter (February) and the summer (August) are sampled across three survey lines (15 sites in each survey line), respectively. The tidal flat of open-coast Myongsasipri is mainly composed of fine to medium sand, the distribution of which shows a coast-parallel trend. Grain-size distribution has a bi-modal trend, and grain size in the winter is coarser than that in the summer. During the winter, the upper tidal flat is dominated by medium sand, while the lower tidal flat is dominated by find sand. Such a feature is attributed to wave-dominated sedimentation in the winter. The finer grains of the summer rather than that of the winter and relationship between texture parameters suggest that tidal energy plays an important role in tidal-flat sedimentation during the summer. This study represents an environmental change from wave-dominated conditions in the winter to tide-dominated conditions in the summer as a result of the seasonal variation in the intensity of onshore-directed winds and waves in the Myongsasipri tidal flat.

Fluvial Deposits Distributed along the Seomjin River (섬진강 유역의 하성 퇴적층에 관한 연구)

  • You, Hoen-Su;Cho, Seok-Hee;Koh, Yeong-Koo
    • Journal of the Korean earth science society
    • /
    • v.21 no.2
    • /
    • pp.174-187
    • /
    • 2000
  • The Quaternary coarse-grained sandy sediments are distributed along the channels of Seomjin River. The fluvial sediments were sedimentologically studied in horizontal and vertical distributions. To analyze depositional environments and facies changes in the sediments, sediment sampling from river mouth to upper stream and desctriptive approaches to the sediment profiles outcropped near Kurye were carried out. The sediments along the stream lines of the river are assigned to very coarse to coarse sand in grain size. The sediment grains are widely scattered in sorting and moderately sorted in average. For skewness and kurtosis, the sediments ranges from very fine to very coarse skewed and from very lepto-kurtic to extremelyl epto-kurtic states, respectively. The sediments are divided into slightly gravelly sand, gravelly sand and sandy gravel in sediment type. The pain shape in the sandy sediments are dominant in equant and tabular forms showing wide varieties. The sandy sediments are mostly poorly sorted and are highly variable in surface texture with SEM. Some smaller grains in the sediments ordinarily show polished surfaces. Of those grains, quartz ones are commonly angular to surounded. On the basis of facies changes and sedimentary structures, outcropped fluvial sediment profiles in Kurye are classified into xGyS, mGyS, gGyS, xSM, xS, mS, mGyM, IgM in facies. These eight facies are reformed as facies assemblage I and ll. The facies assemblage I and II are interpreted as the products of the channel deposits in braided stream and flood plain ones besides channels, respectively. The change facies assemblage I with facies assemblage ll imply that depositional environments hadbeen migrated from braied sream to flood plain ones.

  • PDF

The Paradox of Grant Allen's Physiological Reductionism (그랜트 알렌의 생리학적 환원주의의 역설)

  • Lee, Sungbum
    • Cross-Cultural Studies
    • /
    • v.44
    • /
    • pp.411-430
    • /
    • 2016
  • One of central issues in the Literature and Science discourses during the Victorian era is the relation of physiology to psychology. Many thinkers tackle the question of whether or not psychic phenomena can be reducible to their physiological bases. For instance, Victorian physiologist William Benjamin Carpenter claims that there should be a boundary between physiological and psychological qualities. Yet, his contemporary writer Grant Allen contends for the reduction of psychology into physiology. In the essay, I discuss Grant Allen's work Physiological Aesthetics (1877) so as to eventually problematize his physiological reductionism. I especially highlight the paradox of his physiological aesthetics. In order to clarify my argument, I introduce two concepts: evolutionary aesthetics and physiological reductionism. On the one hand, Allen argues for the development of aesthetic appreciation. The gradual evolution from gaudy to serene colors, for instance, reflects the fine differentiation of sensory organs. He believes that the existence of varied aesthetic pleasures corresponds to the evolution of sensory nerve structures. Nonetheless, Allen ironically gives more weight to the commonality of aesthetic experiences than to this teleological ordering of aesthetic experiences. He argues that there is no fundamental difference among humans in terms of their aesthetic assessments. Furthermore, there is even no essential distinction among plants, animals, and humans in light of their aesthetic appraisals, he states firmly. Although he asserts the gradual advance of aesthetic feelings caused by the intricacy of nervous systems, he simultaneously trivializes the evolution of aesthetic appraisal. In the essay, I highlight this paradox in Allen's physiological aesthetics. It should be underscored, lamentably enough, that Allen seeks biological purity by erasing fine lines among physiology, psychology, and sociality. He estranges aesthetic experiences from subjective variations and their socio-cultural contexts. He makes great efforts to eliminate individual differences and socio-cultural specificities in order to extremely biologize aesthetic experiences. Hence, Allen's physiological aesthetics is marked as the politics of physiological purification.

Identification of DNA Markers Related to Resistance to Herbicide Containing Mesotrione in Tongil Type Rice (통일형 벼에서 메소트리온계 제초제 저항성 연관 DNA marker 탐색)

  • Lee, Ji-Yoon;Cho, Jun-Hyeon;Lee, Jong-Hee;Cho, Su-Min;Kwon, Young-Ho;Park, Dong-Soo;Song, You-Chun;Ko, Jong-Min
    • Korean Journal of Breeding Science
    • /
    • v.50 no.4
    • /
    • pp.387-395
    • /
    • 2018
  • This study was conducted to identify DNA markers related to resistance to herbicide containing mesotrione in Tongil type rice. Two Tongil type elite lines; Milyang154 and Suweon382, showed resistance to mesotrione, whereas the others were susceptible at 20 days after mesotrione application, and severe growth inhibition was observed in the remaining 13 lines. As a result of analysis of mesotrione resistance using 190 $F_2$ populations derived from a cross of Hanareum2 (susceptible) and Milyang154 (resistant), the mesotrione resistance locus was shown to be a single dominant gene with a 3:1 segregation ratio ($X^2=1.19$, P=0.31). To identify a DNA marker closely linked to the mesotrione resistance gene, bulked segregant analysis (BSA) was adopted. The DNA marker RM3501 was identified on chromosome 2 with a recombinant value of 0.53 to the mesotrione resistance gene. Mst1(t) was located between SSR (simple sequence repeat) markers RM3501 and RM324 with a physical map distance of 10.2 Mb-11.4 Mb on chromosome 2. The band pattern of agarose gel electrophoresis of the SSR marker RM3501 showed the same segregation pattern with respect to mesotrione treatment in 20 Tongil type varieties and a $BC_2F_2$ segregation population derived from a cross between Unkwang (resistant) and Hanareum2 (susceptible). Thus, the RM3501 DNA marker could be used in breeding programs for Marker Assisted Selection in mesotrione resistant rice breeding.