• 제목/요약/키워드: Sickle

검색결과 49건 처리시간 0.027초

영양학 연구의 생택학적 접근 (An Ecological Approach to Nutritional Research)

  • 문수재
    • Journal of Nutrition and Health
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    • 제34권1호
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    • pp.98-111
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    • 2001
  • The article demonstrates a method of studying human health and nutrition by applying a multi-disciplinary approach and examines how humans developed and survived by adjusting to their environment. This process involves physiological, cultural and genetic adaptation both independently and interactively. This study postulates that a sound human health may be the result of balance between nutrition and environmental conditions. It is noted that there is a positive correlation between malaria and fava bean intake, and sickle cell anemia and cassava intake. It is also suggested that the difference in disease structure in soybean and non-soybean consumption cultures can be explained by an ecological approach to studying nutrition. This study further suggest that the relationship between nutrition and socio-cultural system. epidmiological study of nutrition and cultural environment nutrition and conceptual characteristics, nutrition and food intake pattern, nutrition and health sociological functions and the physioloical, cultural and genetic adaptation can all be stimulating research subjects to be studied form and ecological point of view. This article also includes the results from a series of ecological studies conducted by the author investigating the relationship between nutritional status of Korean breast-feeding mothers and the composition of the human milk and also the Vitamin D status of Korean and their lifestyle. (Korean J Nutrition 34(1):98-111, 2001)

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접목선인장 줄기썩음병균, Fusarium oxysporum Schlecth. emend. Snyd. & Hans.의 균학적 특성과 병원성 (Mycological Characteristics and Pathogenicity of Fusarium oxysporum Schlecht. emend. Snyld. & Hans. Causing Stem Rot of Cactus)

  • 현익화;이상덕;이영희;허노열
    • 한국식물병리학회지
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    • 제14권5호
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    • pp.463-466
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    • 1998
  • A Fusarium species was isolated from stems of cactus(Hylocereus trigonus) showing rot symptoms at Koyang, Kyonggi province in 1997. This pathogen was identified as Fusarium oxysporum based on mycological characteristics. The rot symptom appeared at the soil line and roughly circular lesions, 1∼3 mm in diameter, appeared on basal stems. The pathogen formed both microconidia and macroconidia. Microconidia were formed abundantly in false-heads on short monophialides, oval to kidney-shaped. Macroconidia were slightly sickle-shaped, 3∼5-septated with an attenuated apical cell and a foot-shaped basal cell. Colony color on PDA was white, peach or purple. Chlamydospores were formed abundantly on PDA. The pathogen was able to cause stem rot symptoms to cactus by wound inoculation as well as non-wound inoculation.

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Fine Structural Observations on Spermatogenesis of the Goldeye Rockfish, Sebastes thompsoni (Teleostei: Scorpaenidae)

  • LEE Jung Sick;OH Yung Keun;HUH Sung-Hoi
    • 한국수산과학회지
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    • 제30권6호
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    • pp.1005-1012
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    • 1997
  • Fine structural changes of the germ cells during spermatogenesis in the goldeye rockfish, Sebastes thompson; were examined by means of the transmission and scanning electron microscopy. A spermatogonium has a large nucleus with a single nucleolus in the interphase. Primary spermatocytes are characterized by the formation of chromatin clumps and presence of the synaptonemal complex in the nucleus. The nucleoplasm of secondary spermatocytes is more condensed than that of primary spermatocytes, and the cytoplasm contains numerous mitochondria, endoplasmic reticulum and Golgi complex. The nuclei of spermatids in metamorphosis show sickle-like shape as the nucleoplasm becomes more condensed. In the cytoplasm of spermatids, the proacrosomal granules are not found at all. A spermatozoon consists of head, neck and tail. The acrosome is absent in the head. Four to five cytoplasmic collars are observed in the posterior portion of the head of spermatozoon. The well developed axonemal lateral fins are observed in the flagellum of spermatozoon.

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광주 효천유적 출토 청동기시대 석기의 재질특성과 원산지 추정 (Material Characteristics and Provenance Presumption for Stone Artifacts of Bronze Age from the Hyocheon Site in Gwangju, Korea)

  • 박성미;이찬희;김지영;정일
    • 보존과학회지
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    • 제21권
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    • pp.5-20
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    • 2007
  • 이 연구는 광주 효천 2지구 유적지에서 출토된 청동기시대 석기를 대상으로 재질분석과 석재의 원산지를 검토한 것이다. 연구대상 석기는 안산암제 굴지구 1점, 납석제 갈돌 1점, 편암제 석겸 1점, 점판암제 반제품 4점이다. 굴지구로 이용된 안산암은 이 유적지 일대에서 쉽게 관찰할 수 있는 암석이다. 그러나 갈돌, 석겸 및 석촉이나 반제품으로 사용된 납석과 편암 및 점판암은 유적지에서 최소한 10km 이상 떨어진 화순군 동면 화순광업소 부근의 노두에서 관찰할 수 있으며 분포지역도 비교적 넓다. 이들을 각각의 석기와 동일 근원암석으로 짝을 이루어 분석하였을 때, 석기와 추정산지 암석은 모두 재질 및 광물학적 특징이 거의 동일하였다. 원소의 거동과 부화 및 호정성과 불호정성을 이용하여 표준화하였을 때도, 석기와 추정산지 암석의 지구화학적 진화경향이 동일한 것으로 보아, 굴지구는 무등산으로부터 운반되어 온 유적지 주변에 분포하는 암석을 원료로 제작한 자급형 석기일 가능성이 상당히 높다. 한편 갈돌과 석겸 및 석촉이나 반제품 석기의 구성암석은 유적지에서 10km 이상 떨어진 화순광업소 부근에서 재료를 조달하여 제작한 외래형 석기일 가능성이 높다. 따라서 외래형 석기의 도입과정에 대하여는 당시 인류의 이동과 함께 전래되었을 가능성, 주변 부족간의 거래에 의한 확산, 전쟁을 통한 전리품 또는 노획품, 물자의 이동과 교역 등, 모든 가능성을 명확히 규명할 수 있는 고고학적 연구가 필요할 것이다.

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금산 수당리유적 출토 철제유물의 금속학적 연구 (Metallurgical Study on the Iron Artifacts Excavated from Sudang-ri Site in Geumsan)

  • 박형호;조남철;이훈
    • 헤리티지:역사와 과학
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    • 제46권3호
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    • pp.134-149
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    • 2013
  • 금산 수당리유적은 5세기 백제세력이 금산 진안을 통해 가야로 연결되는 내륙교통로를 장악하여 가야 세력과 교류를 하였던 것으로 추정되는 유적이다. 출토된 철제대도와 철부, 철겸 등에 대한 금속학적 미세조직 분석을 실시하여 수당리유적에 대한 철기 제작기술을 확인하였으며 비슷한 시기 제작된 철제유물과 비교하여 5세기 전 후의 백제시대 철기 제작기술에 대한 특징과 기술체계를 파악하고자 하였다. 금산 수당리유적에서 출토된 철제유물은 다양한 제작방법이 적용된 것으로 파악되며 제작방법은 단순히 성형만 이루어진 것과 성형 후 제강공정이 이루어진 것, 성형 후 제강공정과 열처리가 함께 이루어진 것으로 크게 세 가지 방법으로 나누어진다. 성형만 실시한 1호 석실분 철겸의 경우 인부와 배부 모두 연한 페라이트 조직이 주를 이루고 있어 무기로서 가지는 실용적 기능이 떨어져 피장자의 부장 의장용으로 제작되었을 것으로 추정된다. 성형을 실시하고 침탄과 같은 제강공정을 실시한 1호 석곽묘의 철부, 12호 석곽묘의 철겸은 담금질과 같은 열처리는 생략하였지만 부위에 따른 제작 공정의 변화를 주게 되어 단순히 부장 의장용이 아닌 농경과 같이 실생활에서 사용할 목적을 가지고 제작된 것으로 판단된다. 성형을 실시하고 침탄, 열처리로 이어지는 제작방법은 5호, 12호 석곽묘 철제대도에서 확인할 수 있다. 열처리로 인하여 강해진 인부조직과 강하면서도 부러지지 않는 배부의 조직은 제작 과정에서부터 무기가 가지는 목적에 맞게 제작되어 피장자가 직접 사용하였던 것으로 추정된다. 금산 수당리 출토 철제유물의 분석결과를 토대로 비슷한 시기 백제권역에 조성된 고분군들 가운데 철제유물의 금속학적 미세조직 연구가 이루어진 천안 용원리유적, 서천 봉선리유적, 서산 부장리유적과 비교하여 철기 제작기술의 특징을 살펴보았다. 분석을 실시한 철제유물의 수가 많지 않아 공통적으로 출토된 철제대도(목병대도)를 통하여 기술변화과정을 살펴본 결과 철제대도(목병대도)는 4세기 이후 담금질이라는 열처리기술이 적용됨을 확인할 수 있었다.

일부 치위생과 학생들의 치면세마교과목 만족도에 관한 연구 (A study on the oral prophylaxis subject satisfaction of the dental hygiene department students in some area)

  • 심형순;이향님
    • 한국치위생학회지
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    • 제9권1호
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    • pp.15-26
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    • 2009
  • The purpose of this study was to prepare improved education guideline by grasping parts and items felt difficult to apply instruments by the students of the dental hygiene department in the practice of oral prophylaxis using manikin and analyzing factors influencing the satisfaction at the oral prophylaxis subject. To achieve this purpose, 285 senior students of the dental hygiene department located in the Kwangju. Jeonnam area who took theory and practice courses of oral prophylaxis but only practiced the manikin from the second semester of 1st year were selected as the subjects. The following results were obtained. 1. In the manikin, the most difficult part was maxillary anterior lingual in the use of explorer, sickle scaler, and universal curet, and maxillary right posterior lingual was in the use of gracey curet. In the dentiform, the most difficult item was instrument stroke in the use of explorer, sickle scaler, universal curet and gracey curet. 2. The highest stressor was the lack of knowledge and skill in practice of oral prophylaxis, followed by the lack of confidence, and difference between theory and practice in oral prophylaxis. The overall practice satisfaction was 3.23 at oral prophylaxis. The highest satisfaction was found in patient and operator position(3.51), followed by basic skill(3.34), the way to use hand instrumentation(3.16), and the way to use oral examination instrumentation(3.01). 3. According to school records, satisfaction at oral prophylaxis practice satisfaction was 3.36 of good, 3.24 of fair, and 3.06 of poor, suggesting significant difference(p<0.05). Students who participated just in practice during a school term showed 3.47 of satisfaction. The highest satisfaction was found in a full-time professor as a professor in charge(3.24) and there was significant difference(p<0.05). 4. The highest correlated factor between oral prophylaxis theory and practice satisfaction was curriculum satisfaction. The use of hand instrumentation was found to have the greatest effect on the practice satisfaction at oral prophylaxis, followed by basic skill, the way of basic instrumentation, and position. There was statistically significant difference(p<0.01).

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Rotary Mower의 제작과 그 이용에 관한 연구 (A Study on the Design of Rotary Mower and Its Utilization.)

  • 최규홍
    • 한국농공학회지
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    • 제17권4호
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    • pp.3897-3920
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    • 1975
  • Since the most of Korean dairy and cattle raising farms are too small to introduce western mechanized farming, it is necessary to develope small size equipments. This study has been carried to develop a rotary mower as on attachment of 8 to 10 horse powertiller which is widely spread in rural area. It will not ony be helpfull for the farmers to harvesting hay grass but also desirable to increase the power tiller utility. The protto type rotary mower designed through the fundamental investigations, has been modified and improved through the field trials, and a series of field tests has been carried to investigate its performance and economic feasibility comparing with existing vailable harvesting equipments. The results are as follows; 1. To increase the stability, two guide wheels are attached to both side of the protto type rotary mower. 2. To prevent the clinging of tall grasses, the vertical driving shafts are covered with cylindrical protectors. 3. The cutting height is adjustable in 8 steps from 2.5 to 20 centimeters by changing the length of guide wheel legs. 4. The practical Critical cutting speed were always higher than theoretical value in both case of single cutting blade and three when the cutting depth was 25 millimeter. 5. The peripheral speed of cutting blade was varied in response to the change of engine speed, mean while the peripheral speed was adequate as it was changhed from 25 to 35 meter per second when the power tiller is operated in proper working ground speed. 6. The time requirement to harvest 10 a were 88.7, 54.6 and 41.4 minutes for the first, second and third stage of ground speed respectively, and because of the difficulty of delivery, it was observed that operating with fourth stage of ground speed was not recomanendable when the grass height is taller than 90 centimeters. 7. The performance of rotary mower were 1.1-1.7, 1.4-4.0, 3.8-11.8 and 7.4-22.0 times of reciprocating mower, portable disc type cutter, hay scythe and ordinary sickle respectively. 8. When the slope exceeds, 20 degree the downward harvesting operation was impossible because of the excessive front end weight, while less than 5 degree of land slope did not effect in field operation. 9. Increased traveling spee caused higher cutting height and slight cutting failure, but seems not to effect to the gross yield, and the efficiency of cutting width were from 83 to 94 precent. 10. Tn rank of economy were rotary mower (3,2 stage operation), reciprocating mower, hay scythe, portable disc type cutter and sickle in order when the annul operation exdeeds 100 hours. From the above results, it is convinced that the protto type rotary mower is good enough to the livestock farmers as a hay harvesting equipment because of its economy, hardiness in operating and its out standing performance and hopefully it will contribute to the extension of Korean livestock farming.

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우리나라 남해에서 출현한 새다래과(농어목) 한국미기록종, 흰꼬리타락치 Taractichthys steindachneri (First Reliable Record of the Sickle pomfret, Taractichthys steindachneri (Bramidae: Perciformes) from Korea)

  • 김병직;김진구;유정화;박지태
    • 한국어류학회지
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    • 제24권3호
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    • pp.230-233
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    • 2012
  • 과거 우리나라 남해에 출현하는 것으로 알려졌던 농어목 새다래과의 한국미기록종 흰꼬리타락치(Taractichthys steindachneri)에 대해 제주도를 포함한 남해에서 채집된 2개체(표준체장 224.7~406.5 mm)의 표본을 근거로 형태적 특징을 상세히 기재하였다. 본 종은 양측 배지느러미가 서로 멀리 떨어져 위치하는 점, 미병부 배측에 반월상의 홈이 있는 점, 등지느러미와 뒷지느러미가 길게 신장하는 점, 그리고 체색이 전체적으로 검고 꼬리지느러미 후연이 백색인 점이 특징이다.

광주(光州) 신창동(新昌洞) 저습지출토(低濕地出土) 나무문짝(비문(扉門))에 관한 연구(硏究) (A Study on the Door Discovered at the Shinchang-dong Wetland Site)

  • 천득염;신상효
    • 건축역사연구
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    • 제15권5호
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    • pp.7-18
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    • 2006
  • A lot of relics were unearthed in the Shinchang-dong wetland site, which can help restore prehistoric life style, including construction tools such as wood doors, wood hammers, ax handgrips, sickle handgrips, wedges, awls, wood pillars and connection members, food vessels made of earth or wood and fish, shell fish, seeds and remains of weapons. In particular, a door was found in the site, which was measured at 110cm long and 37cm wide. If restored it will be 75cm wide. The door seems to date back as far as the 1st century B. C., which would be the oldest one ever discovered in Korea. This paper is intended to explore the implications of the door by investigating the environment of the Shinchang-dong wetland site bearing the relics intact, manufacturing techniques and times of manufacturing of the door as well as attributes of doors presented in the literature related to old time architecture such as Goguryeo tomb paintings and house-shaped vessels. It also intends to provide basic data for study of residential architecture in prehistoric times.

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The Design and Development of An Oil Palm Fresh Fruit Bunch Cutting Device

  • Ahmad, Desa
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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    • pp.458-468
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    • 1996
  • The Oil Palm industry has developed tremendously with the increasing of planted area from 54,000 hectaresin 1960 to about 2.28 million hectares in 1995. This is expected to increase further to 2.5 million hectares by the year 2000. However, there has been an increasing difficulty in obtaining sufficient labour for the oil palm plantations. At present , harvesting of oil palm fresh fruit is facing an acute shortage of workforce as the workers are much more attracted to the better working environment and salary in the industrial sector. Harvesting of short palm is easily done by using a chisel attached to a short steel pole. Cutting is done by moving the tool at high speed to the target. The weight of the tool coupled with the speed of throwing will produce enough energy to cut the bunch stalk. In this cutting method, sharpness of the cutting device, weight of tool and the speed of throwing contribute to the efficiency of the tool . For the tall palms, a sickle attached to a ong pole is used and the job is more difficult compared to the short palms. Lifting of pole and cutting jobs require great effort and skills. This paper describes the basic design needs in developing an appropriate device that is practical for field use. A prototype design was developed and tested.

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