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Study on the Fine Structure of Retina of Anterior Lateral Eyes in Pardosa astrigera L. Koch (Aranea: Lycosidae) (별늑대거미 (Pardosa astrigera L. Koch) 전측안(前側眼) 망막(綱膜)의 미세구조(微細構造)에 관한 연구)

  • Jeong, Moon-Jin;Moon, Myung-Jin
    • Applied Microscopy
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    • v.24 no.3
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    • pp.1-9
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    • 1994
  • Pardosa astrigera possessed eight eyes arranged in three rows on the frontal carapace. A pair of small anterior lateral eyes (ALE) flanked each side by an anterior median eyes (AME) lay along the anterior margin that was situated on the anterior row of clypeus. The anterior lateral eye was composed of cornea, vitreous body, and retina. Cornea was made up mainly of exocuticle lining the cuticle. Lens in anterior lateral eye was biconvex type which bulged into the cavity of the eyecup. Outer and inner central region of lens were approximately spherical with radius of curvature $5.6{\mu}m$ and $12.5{\mu}m$, respectly. Vitreous body formed a layer between the cuticular lens and retina. They formed biconcave shape. Retina of the anterior lateral eyes was composed of three types of cells: visual cells, glia cells, and pigment cells. The visual cells were unipolar neuron, as were the receptor of the posterior lateral eye. But cell body was unique to the anterior lateral eyes. They were giant cell, relatively a few in number, and under the layer of vitreous bodies. Each visual cell healed rhabdomeres for a short stretch beneath the cell body. Rhabdomes were irregulary pattern in retina and electron dense pigment granules scattered between the rhabdomes. Glia cell situated at the cell body of visual cell and glia cell process reached to rhabdomere portion. Below the rhabdome, tapetum were about $30{\mu}m$ distance from lens, which composed of 4-5 layers. It was about $25{\mu}m$ length that intermediate segment of distal portion of visual cell. Electron dense pigment granules between the intermediate segment were observed.

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Spatial Genetic Structure and Genetic Diversity of a Rare Endemic Juniperus chinensis var. sargentii in Mt. Halla, Korea (희귀식물인 눈향나무(Juniperus chinensis var. sargentii)의 공간분포에 따른 유전구조 및 유전적 다양성)

  • Choi, Hyung-Soon;Hong, Kyung-Nak;Chung, Jae-Min;Kim, Won-Woo
    • The Korean Journal of Ecology
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    • v.27 no.5
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    • pp.257-261
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    • 2004
  • Juniperus chinensis var. sargentii Henry is a short and creeping evergreen shrub which reaches about 50㎝ in height and occurs in the northeast Asia and in high mountains over the South Korea. Its distribution is restricted, and the number of individuals are gradually decreasing. This study was conducted to estimate spatial pattern, genetic diversity and spatial genetic structure of J. chinensis var. sargentii. A total of 131 clumps were studied in the study area (40m × 60m). The spatial pattern of this population was random (Aggregation index R=1.031). In spite of the small number and the limited distribution, the level of genetic diversity (Shannon's index 1=0.463) was relatively high as compared with those of other plant species with similar ecological characteristics. ISSR genotypes of all individuals were investigated to find the genetic relationship of clumps and genets. Fifteen clumps were composed to be clones, and a total of 116 unique genotypes were composed by separate genets. Spatial autocorrelation analysis using Tanimoto distance showed that the genetic patch was established within 8m. The effect of clonal reproduction on genetic structure was almost nothing.

THREE DIMENSIONAL FINITE ELEMENT ANALYSIS ON THE MANDIBULAR CANTILEVERED PROSTHESIS SUPPORTED BY IMPLANTS (임프란트로 지지된 하악 켄티레버 보철물의 3차원 유한요소 분석)

  • Cho, Chul;Shin, Sang-Wan;Kwon, Jong-Jin
    • The Journal of Korean Academy of Prosthodontics
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    • v.38 no.5
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    • pp.724-743
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    • 2000
  • One of the biggest clinical problems of osseointegrated implant prosthesis is the excessive stress caused by bite forces which are transfered directly into the bone through the osseointegrated implant fixtures. So several biodynamic problems occur when there is an excessive fatigue stress. The factors of stress distribution are the number, kind, position, arrangement of the implants, and the distance between the implants, and the kind, quality of superstructure prosthesis and connection type between the rest implant and the superstructure. Recently, a distal short additional implant, socalled rest implant, is employed to reduced the stresses in conventional cantilevered prostheses. This study was undertaken to analyze the stresses transfered by osseointegrated implant cantilevered prostheses depending upon the number and the position of implants, the presence of rest implant, and the type of their connection. Three dimensional finite element analysis was attempted using ANSIS ver. 5.3 program under IBM INDIGO computer. The results were as follows : 1. The rest implant influenced on the pattern of stress distribution on the anterior area of the mandible and the superstructure. 2. In the group employing the rest implants, the fixed type of connection between the rest implant and the superstructure was more stable than the ball attachment type on the stress distribution. 3. In the group employing the ball attachment between the rest implant and the superstructure, the case with 4-implants(on canine, premolar) was little more stable than the case with 6-implants and the case with 4-implants(on incisor, premolar) on the stress distribution. 4. In the cantilevered group, the case with 4-implants(on incisor, premolar) and the case with 6-implants were more stable than the case with 4-implants(on canine, premolar) on the stress distribution. 5. In all of the group, the case with 6-implants and the fixed type of connection was the most stable and the case with 4-implants (on canine, premolar) was the most unstable on the stress distribution.

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Development of Biotelemetry Method by Combining the SSBL Method and the Pinger Synchronizing Method (1) - Design and production of system - (SSBL 방식과 핑거동기 방식을 조합한 바이오텔레메터리 방식의 개발 (1) -시스템의 설계 및 제작 -)

  • 박주삼;고탁창언
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.3
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    • pp.218-229
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    • 2003
  • A new biotelemetry method that the installation and the treatment of equipment is convenient and the instantaneously detailed location of the fish attached the pinger is able to track comparatively easily was developed. The receiving system in this biotelemetry method was advanced for track the detailed behavior of the fish by the miniature tracking pinger, because it was a burden to fish to add the pinger with the water temperature and the pressure sensor. By combining of the super short base line (SSBL) method to detect the direction of pinger and the pinger synchronizing method to measure the range from receiving transducer to pinger, the three dimensional locations of fish to the receiving transducer is gotten instantaneously. The receiving system is devised to realize the high precision or wide detection range by application of the basic design method for receiving system of biotelemetry developed by the present authors and the hydrophone array configuration. The measurement distance error in the pinger synchronizing method is minimized through the correction of which the deviation of transmission pluse period of pinger is caused by changing water temperature. A prototype system which is able to track the instantaneously detailed location of the fish by the SSBL and pinger synchronizing biotelemetry (SPB) method was produced.

Loop Suture Technique for Flexor Digitorum Profundus Tendon Repair in the Insertion Site (고리 봉합법을 이용한 심부 수지 굴건 종지부에서의 건봉합)

  • Lee, Kyu-Cheol;Lee, Dong-Chul;Kim, Jin-Soo;Ki, Sae-Hwi;Roh, Si-Young;Yang, Jae-Won
    • Archives of Plastic Surgery
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    • v.37 no.5
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    • pp.650-658
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    • 2010
  • Purpose: In the case of repair for far distal parts of FDP (Flexor digitorum profundus) division, the method of either pull-out suture or fixation of tendon to the distal phalanx is preferred. In this paper, the results of a modified loop suture technique used for the complete division of FDP from both zone 1a and distal parts of zone 1b in Moiemen classification are presented. Methods: From July 2006 to July 2009, the modified loop suture technique was used for the 10 cases of FDP in complete division from zone 1a and distal parts of zone 1b, especially where insertion sites were less than 1 cm apart from a tendon of a stump. In a suture technique, a loop is applied to each distal and proximal parts of tendon respectively. Core suture of 2-strand and epitendinous suture are done with PDS 4-0. Out of 10 patients, the study was done on 6 patients who were available for the followup. The average age of the patients was 49.1 years (in the range from 26 to 67). 5 males and 1 female patients were involved in this study. There were 3 cases with zone 1a and distal parts of zone 1b. The average distance to the distal tendon end was 0.6 cm. There were 5 cases underwent microsurgical repair where both artery and nerve divided. One case of only tendon displacement was presented. The dorsal protective splint was kept for 5 weeks on average. The results of the following tests were measured: active & passive range of motion, grip strength test, key pinch and pulp pinch test. Results: The follow-up period on average was 11 months, in the range from 2 to 20 months. There was no case of re-rupture, but tenolysis was performed in 1 cases. In all 6 cases, the average active range of motion of distal interphalangeal joint was 50.8 degree. The grip strength (ipsilateral/contralateral) was measured as 88.7% and the pulp pinch test was 79.2% as those of contralateral side. Flexion contracture was presented in 2 cases (15 degree on average) and there was no quadrigia effect found. Conclusion: Despite short length of tendon from the insertion site in FDS rupture in zone 1a and distal parts of zone 1b, sufficient functional recovery could be expected with the tendon to tendon repair using the modified loop suture technique.

Characteristics of Plasma Discharge according to the Gas-flow Rate in the Atmospheric Plasma Jets (대기압 플라즈마 제트의 기체 유량에 대한 방전 특성)

  • Lee, Won Young;Jin, Dong Jun;Kim, Yun Jung;Han, Gook Hee;Yu, Hong Keun;Kim, Hyun Chul;Jin, Se Whan;Koo, Je Huan;Kim, Do Young;Cho, Guangsup
    • Journal of the Korean Vacuum Society
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    • v.22 no.3
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    • pp.111-118
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    • 2013
  • The influence of gas flow on the plasma generation in the atmospheric plasma jet is described with the theory of hydrodynamics. The plasma discharge is affected by the gas-flow streams with Reynolds number (Re) as well as the gas pressure with Bernoulli's theorem according to the gas flow rate inserted into the glass tube. The length of plasma column is varied with the flow types such as the laminar flow of Re<2,000 and the turbulent flow of Re>4,000 as it has been known in a general fluid experiments. In the laminar flow, the plasma column length is increased as the increase of flow rate. Since the pressure in the glass tube becomes low as the increase of flow velocity by the Bernoulli's theorem, the breakdown voltage of plasma discharge is reduced by the Paschen's law. Therefore, the plasma length is increased as the increasing flow rate with the fixed operation voltage. In the transition of laminar and turbulent flows, the plasma length is decreased. When the flow becomes turbulent as the flow rate is increasing, the plasma length becomes short and the discharge is shut down ultimately. In the discharge of laminar flow, the diameter of plasma beam exposed on the substrate surface is kept less than the glass diameter, since the gas flow is kept to the distinct distance from the nozzle of glass tube.

Prevalence and environmental risk factors for respiratory symptoms among elementary school children in a city (도시지역 초등학교 저학년 학생들의 호흡기계 증상 유병률에 영향을 주는 환경위험요인)

  • Park, Hye-Sook;Lee, Bo-Eun;Ha, Eun-Hee;Kim, Nam-Hee;Hong, Yun-Chul;Lee, Youn-Kyung;Cho, Yong-Sung
    • Journal of the Korean Society of School Health
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    • v.16 no.2
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    • pp.1-11
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    • 2003
  • PURPOSE: The aim of our study was to assess the prevalence of respiratory symptoms and to determine their environmental risk factors in school children living in a city where traffic is particularly heavy. METHODS: From November 12th to November 19th, 2002, we sent questionnaires to parents for children's health and environmental factors, and ninety eight percent (516) of parents responded. RESULTS: The lifetime prevalence of chronic respiratory illness was 12.2% and 13.2% for wheeze, and 6.6% for physician diagnosed asthma. Using multiple logistic regression model, we found that family history of asthma(OR=3.47, 95% CI 1.36-8.78), atopy dermatitis(OR=5.48, 95% CI 2.37-12.66), and pets at home(OR=3.22, 95% CI 1.26-8.23) were associated with chronic respiratory illness in last 12 months. We also found that family history of asthma(OR=3.28, 95% CI 1.16-9.31), atopy dermatitis(OR=2.89, 95% CI 1.11-7.54), and short distance between the house and road(OR=2.85, 95% CI 1.03-7.87) were associated with asthma in last 12 months. CONCLUSIONS: Elementary school children in a city had a relatively high prevalence of chronic respiratory illness and symptoms. In addition to genetic factors, pets at home and outdoor air pollution are associated with respiratory illness and Symptoms in school children.

A Study on the Optimal Message Length of File Transfer Protocol via Satellite and Terrestrial Links (위성과 지상 회선에서 파일 전송 프로토콜의 최적 메세지 길이에 대한 연구)

  • Park, Jin-Yang;Lee, Yong-Hun;Kim, Jeong-Ho;Lee, Sang-Beom
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.1
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    • pp.215-223
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    • 1997
  • The advantages of service in satellite links are representatively a long distance and large capacity transfer and simultaneous communication. And terrestrial links are of high speed and high quality data transfer Therefore a combined form of characteristics of satellite and terrestrial links is desirable to furnish a good quality service to subscribers. And in satellite links an analysis method and a simulation method of file transfer are conducted to evaluate the efficiency of file transfer. The parameters are used the message length and transmission time, and the number of chain record and transmission time. From the results of evaluation, in satellite links, it is found that when the message length is shorter than 512 bytes, the file transmission time becomes extremely long and when the message length is set at 1024 bytes, the file transmission time abruptly increase from 2048 bytes. Also it is confirmed that when the number of chain record is under 15, the file transmission time becomes extremely long and if the number increase up to 90,the time becomes gradually short and over 90,it becomes constant.Therefore,from the result of file transmission in th case of utilizing satelite links,it is confirmed that the optimum message length in the minmum transmission time is present closely at 1024 bytes.Also it is confirmed that when the satelite transmission sped becoms smaller from 24kbps to2400bps,the optimum message length also becomes smaller from 640 bytes to 256bytes.

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A Study on Effect of Earth Pressure Reduction and the Silo Earth Pressure of the Retaining Wall by CLSM Backfill with Waste Foundry Sand (폐주물사를 이용한 유동성 채움재의 절토구간 옹벽 뒤채움시 사일로토압 및 토압경감효과 연구)

  • Cho, Jae-Yun;Lee, Kwan-Ho;Cho, Yoon-Ho
    • International Journal of Highway Engineering
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    • v.4 no.2 s.12
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    • pp.19-31
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    • 2002
  • The recycling of waste foundry sand(WFS) and fly ash as by-products of industry is one of the urgent problem to deal with. For the recycling of these materials, CLSM(controlled low strength materials) concept was adopted. This research has been done for last three years. In this research, couple of selected waste foundry sand and fly ash were used as fine aggregate. Also, WFS modified by Proper chemical liquid was used for the comparison. The main focus is to evaluate the silo earth pressure and the reduction effect due to the use of CLSM instead of normal fine aggregate. Silo effect, which occurs at short distance between retaining wall and backfill, was not detected because the characterization of CLSM is highly different from that of normal aggregate. Therefore, the theory for earth pressure, like Rankine theory or Coulomb theory, should be carefully used for CLSM. The reduction of earth pressure for modified WFS is higher than the others. But, the final earth pressure is converged at very small value, even though the reduction effect depends on the curing time.

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Spatial Interpolation of Hourly Air Temperature over Sloping Surfaces Based on a Solar Irradiance Correction (일사 수광량 보정에 의한 산악지대 매시기온의 공간내삽)

  • 정유란;윤진일
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.4 no.2
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    • pp.95-102
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    • 2002
  • Spatial interpolation has become a common procedure in converting temperature forecasts and observations at irregular points for use in regional scale ecosystem modeling and the model based decision support systems for resource management. Neglection of terrain effects in most spatial interpolations for short term temperatures may cause erroneous results in mountainous regions, where the observation network hardly covers full features of the complicated terrain. A spatial interpolation model for daytime hourly temperature was formulated based on error analysis of unsampled site with respect to the site topography. The model has a solar irradiance correction scheme in addition to the common backbone of the lapse rate - corrected inverse distance weighting. The solar irradiance scheme calculates the direct, diffuse and reflected components of shortwave radiation over any surfaces based on the sun-slope geometry and compares the sum with that over a reference surface. The deviation from the reference radiation is used to calculate the temperature correction term by an empirical conversion formula between the solar energy and the air temperature on any sloped surfaces at an hourly time scale, which can be prepared seasonally for each land cover type. When this model was applied to a 14 km by 22 km mountainous region at a 10 m horizontal resolution, the estimated hourly temperature surfaces showed a better agreement with the observed distribution than those by a conventional method.