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배추무사마귀병 뿌리혹의 부패에 미치는 몇가지 환경요인 (Some Environmental factors Affecting Decay of Root Galls in Club Root Disease of Chinese Cabbage)

  • 김충회;조원대;김홍모
    • 농약과학회지
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    • 제4권4호
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    • pp.61-65
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    • 2000
  • 배추 무사마귀병 뿌리혹의 부패에 미치는 온도 토양수분 담수, 토양미생물의 영향을 실내에서 조사하였다. 뿌리혹의 완전부패까지 소요일수는 온도가 높을수록 빨라서 $32^{\circ}C$ 이상에서는 3일, $16{\sim}20^{\circ}C$에서는 12일, $8^{\circ}C$에서는 28일이 소요되었다. 토양수분이 높을수록 뿌리혹의 부패도 빨라서 포화수분의 경우 $32^{\circ}C$에서는 3일, $24^{\circ}C$에서는 8일이 소요되었고, $32^{\circ}C$에서는 토양수분의 영향이 $24^{\circ}C$에서 보다 낮았다. 담수에 의한 뿌리혹의 부패촉진효과는 $32^{\circ}C$에서는 나타나지 않았으나, $24^{\circ}C$$12^{\circ}C$에서는 높았다. 뿌리혹의 부패에 대한 외부 토앙미생물의 영향은 나타나지 않았다. 뿌리혹의 부패에 가장 큰 영향을 미치는 요인은 온도였으며 온도가 비교적 낮을수록 다른 환경요인에 의해 영향을 많이 받는 것으로 나타났다. 뿌리혹내 휴면포자는 뿌리혹의 부패 후 시간이 경과할수록 그 성숙도가 증가하였으며, 신선한 뿌리혹은 부패한 혹에 비하여 휴면포자의 밀도도 낮았고 그 성숙도도 저조하였다. 완전히 부패한 뿌리혹내 휴면포자의 밀도는 1 g 조직당 $6.5{\times}10^{6}$개였으며 성숙 휴면포자율도 95% 이상에 달하였다.

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협설만곡치아의 파노라마방사선영상소견에 대한 연구 (A study of the panoramic radiographic images of the buccolingual dilaceration)

  • 김영호;정환석;허경회;이원진;허민석;이삼선;최순철
    • Imaging Science in Dentistry
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    • 제40권1호
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    • pp.39-44
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    • 2010
  • Purpose : We want to identify the appearance of the buccolingual root dilaceration teeth in the panoramic views and specify the characteristics of these teeth. Materials and Methods : One thousand-six patients were examined on the basis of both panoramic and CT image criteria. We diagnosed and excluded certain teeth from the samples; both prosthodontic or pathologic lesion appearing teeth and mesiodistally dilacerated ones. We meticulously discerned buccolingually dilacerated teeth in the CT images and total 48 samples were selected. The degree of severity in dilaceration was standardized by 2 types of criteria. The samples were differentiated into 3 groups and again categorized into six types showing from the panoramic views: irregular view on the root apex area, clear blunt on the root tip, stepping on root tip, double lamina dura or double tip, arrow-target shaped root, bull's eye, normal view. Results : The types of teeth selected from total 48 buccolingual root dilaceration samples were mandibular first and second molar, premolars, canines, and lateral incisors. The direction of dilaceration was an even percentage to each buccal and lingual side for most selected teeth, however, that of both canines and lateral incisors were directed in almost a buccal side. In the panoramic views, the root types of the buccolingually dilacerated teeth were irregular view on the root apex area, clear blunt on the root tip, stepping on root tip and normal types were almost always normal view. The more severity in dilareated degree, the more chances of observation in the panoramic views were clear blunt on the root tip and stepping on root tip. Conclusion : As observed in the shape of stepping on root tip or double lamina dura in the panoramic views, there can be much more probability to diagnose as a buccolingually dilacerated root.

GT rotary file을 이용한 만곡 근관형성시 작업 효율 및 file 변형 발생에 관한 연구 (A STUDY OF WORKING EFFICIENCY AND FILE DEFORMATION OF GT ROTARY FILE IN CURVED CANALS)

  • 신주희;백승호;배광식;임성삼;윤수한;김병현
    • Restorative Dentistry and Endodontics
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    • 제26권5호
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    • pp.418-435
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    • 2001
  • Root canal preparation process is of utmost importance in successful treatment of root canal. Also, one of the most important purpose of the root canal preparation is to enlarge the root canal three dimensionally without changing the curvature of the root canal However as the curvature of the root canal increases, there are many difficulties involved in formation of optimum root canal. Therefore in order to solve the above mentioned problems, new developments in methods of root canal preparation and equipments for such purposes were made. Recently, vigorous studies about newly introduced engine-driven nickel-ti-tanium rotary file are conducted. As shown in research results to dates, it is well established that the use of nickel-titanium file is better suited for curved root canal than stainless steel file in maintaining the curvature or root canal and reducing the deformation of root canal. However it is also acknowledged that there are a few discrepancies in research results according to protocol, due to failure to remove variables in experiments. In addition, although it is recommended by the manufacturer that the GT rotary file should maintain a low rotational speed of 150~350rpm and 'light pressure' as light as not to break the lead of a pencil, academic studies about the vertical force which is not yet standardized are not sufficiently explored. Therefore, this research devised and utilized a special research equipment to standardize the appropriate range of vertical force for GT rotary file through experiments by breaking of the lead of a pencil as expressed by the manufacturer and to accurately measure factors involved through repeating and recreating the environment of root canal preparation. Forming nine experimental groups by varying the vertical forces (150g. 220g, 300g) and rpm (150rpm, 250rpm, 350rpm), the effects of changing vertical forces and rpm on working efficiency were measured in terms of time expended in root canal preparation by crown-down method using a transparent resin block with 35 degree curvature and GT rotary file (z-test). The following research using this special research equipment that involved nine experimental groups and varying the vertical force for root canal preparation from 300g which is within the normal vertical force range to 700g and 1000g which fall outside the normal rpm range. The results were as follows : 1. Analysis of the experiment results revealed that the time spent in root canal preparation decreased as the vertical forces and rpm increased (p<0.05). Also, the effects of rpm were greater than those of the vertical forces within the normal vertical force range ($\beta$-weight test). 2. Observation of the deformation of GT rotary file revealed that deformation increases in a direct correlation with the vertical force increase and in a reverse correlation with the rpm decrease. In the case of the vertical forces close to the normal range, the probability of GT rotary file deformation were quite different depending on the rpm changes. In the case of greater vertical forces, the occurrences of deformation of the file were more frequent regardless of the rpm changes. 3. Deformation and breakage of file were also commonly observed in the expended time measurement experiments and GT rotary file deformation experiments in which low speed rpm (150rpm) was used and at the curved portion of the resin block.

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적변삼 외피에서 지질, 페놀성물질 및 철 성분의 축적에 관한 연구 (Accumulation of Crude Lipids, Phenolic Compounds and Iron in Rusty Ginseng Root Epidermis)

  • 이태수;목성균;천성기;윤종혁;백남인;최정
    • Journal of Ginseng Research
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    • 제28권3호
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    • pp.157-164
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    • 2004
  • 인삼재배지에서 나타나는 적변삼 외피세포 조직의 특성과 화학성분을 조사하였던 바 그 결과를 요약하면 다음과 같다. 1. 적변외피는 현미경 관찰결과 적색이 아닌 황색으로 보였으며, 적변외피의 세 포층수는 10∼13층으로 건전외피의 5∼6층에 비해 2배 정도 많았고, 외피층의 두께에 있어서는 적변외피가 179 $\mu\textrm{m}$로서 건전외피의 55$\mu\textrm{m}$에 비해 3.2배 정도 더 두꺼웠다. 2. 착색도는 적변외피가 건전외피에 비해 5.5배 정도 짙게 나타났으며, 적변물질의 각 추출분획별 용해도는 비극성 보다는 극성용매에서 높았고, 또한 UV-spectrum은 275∼280nm에서 흡광 최대를 나타냈다. 3. 적변외피는 지질성 물질은 물론 산불용성 에스테르화 페놀물질, 산불용성 결합 페놀물질, 산불용 축합성 페놀물질, 불용성 결합 페놀물질 및 유리 페놀 물질 함량이 건전외피에 비해 많았으며 철의 함량에 있어서도 적변외피가 2,220 ppm으로 건전외피의 820 ppm 보다 2.7배 정도 많았다. 4. 적변삼은 인삼뿌리가 분포된 근권환경의 어떤 외적환경에 의해 뿌리가 stress를 받을 때 자체방어 물질인 phenol 물질이 외피로 배출되면서 외피의 지질성 물질과 polymerization되고 이때 철(Fe)이 체놀성 물질과 강하게 chelating 되는 것으로 추정된다.

창포(Acorus calamus L. )뿌리 건조분말의 식품학적 성분 (II)지방산, 유기산, 무기질, 비타민 C, 총페놀 및 사포닌 (Food Nutritional Compositions in Dried Powder of Root of Acorns calamus L. (II) Fatty Acids, Organic Acids, Minerals, Vitamin C, Total Phenolics and Saponin)

  • 김준한;구건효;김종국;이진만;문광덕
    • 한국식품저장유통학회지
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    • 제9권4호
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    • pp.380-384
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    • 2002
  • 창포의 뿌리를 주근(main root)과 측근(lateral root)으로 분리하여 3$0^{\circ}C$ 열풍건조분말의 주된 포화지방산으로는 caprylic acid, pentadecanoic acid, stearic acid 및 heneicosanoic acid 등 10종이 확인되었고, 이들은 각각 주근과 측근의 경우 caprylic acid가 28.35%, 31.44%이었고, 불포화지방산으로는 linoleic acid, palmitoleic acid 및 linolenic acid 등 6종이 확인되었고 이들 중 가장 높은 함유량을 보인 linoleic acid가 주근에 25.55%, 측근에 23.43%가 함유되어 있었다. 주요 유기산으로는 주근과 측근에 succinic acid, malic acid 및 citric acid 등으로 구성되어 있었고, 특히 succinic acid가 주근과 측근에서 각각 2,790 mg%, 2,630 mg%로 높은 함량을 함유하고 있었다. 무기질로는 K, Ca, p, Mg, Na, Fe, Zn, Mn, Cu 등 9종을 함유하고 있었으며, 창포뿌리의 주된 무기질로 확인된 K의 함량은 측근에 454 mg%로 주근의 194 mg% 보다 매우 높은 함량을 나타내었다. Ascorbic acid 함량은 주근과 측근에 각각 113.8 $\mu\textrm{g}$/g, 125.1 $\mu\textrm{g}$/g을 함유하고 있었고, 총페놀성 물질 함량은 주근에 463 mg%, 측근에 474 mg%로 매우 높은 수준이었으며 조사포닌의 함량은 주근에 2.51%, 측근에 3.39%로 높은 함량을 보였다.

고수의 향미성분에 관한 연구 (A Study on the flavor constituents of the Coriander(Coriandrum sativum L))

  • 김경자;최옥자;김용두;강성구;황금희
    • 한국식품조리과학회지
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    • 제17권1호
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    • pp.80-90
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    • 2001
  • This study was carried out to investigate to proximate compositions, free sugars, organic acids, amino acids, and volatiles from the fresh leaf, root and seed of coriander. The research results are as follows: Moisture was 79.93% in the leaf, 81.89% in the root. Crude protein, crude lipid and crude ash were the highest in the seed. Ascorbic acid was 65.4mg% in the leaf and 37.83mg% in the root. Glucose, fructose and sucrose were the major free sugars. Glucose was 7.92mg% and fructose 7.51mg% in the leaf. Sucrose was 17.34mg% in the root, highest level. Among organic acids, malic acid was 354.55mg% in the leaf, the highest level. The content rate of organic acids was high in the order of leaf, seed and root. The content rate of total amino acid was high in the order of seed, root and leaf. Glutamic acid and aspartic acid were high in the leaf and root. Glutamic acid and proline were high in the seed. The content rate of free amino acid is the same as that of total amino acid. Glutamic acid and serine were high in the leaf and seed. Glutamic acid and treonine were high in the root. The contents of total amino acid in each parts of the coriander was higher than that of free amino acid, The composition of amino acid in the total amino acid and free amino acid was different. The volatile constituents were extracted by steam distillation method and analyzed by GC-Mass. The content of the volatile constituents was 45.31mg% in the leaf, (E)-2-decenal was the highest, followed by decanal, 2-dodecenal, (E)-2-decen-1-ol in order, aldehyde and alcohol was major constituents. The content of the volatile constituents was 36.01mg% in the root and 54.37mg% in the seed. linalool was the highest in the root and seed. it was 22.27 %, 53.67% in root and seed.

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삼칠근(三七根)의 형태(形態)에 관한 연구(硏究) (A Study on a Morphological Identification of Notoginseng Radix)

  • 문성호;이영종
    • 대한본초학회지
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    • 제23권2호
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    • pp.25-31
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    • 2008
  • Objectives : In order to distinguish morphological characteristics of trunk bark and root bark of Ulmus davidiana var. japonica (Rehder) Nakai and the trunk bark and root bark of Hemiptelea davidii Planchon were sampled and compared in terms of their external and internal features with flour states according to their medical use, through microscopic examination. Methods : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and the flour of it was mounted by the liquid made by the same ratio of each of glycerin, acetic acid, and water, and then observed and photographed by olymphus-BHT. Results : 1. Internal Features 1) A large parenchymatous cell was observed in the phloem of the slice of both trunk bark and root bark of Ulmi Cortex, However, both of the trunk bark and root bark of Hemipteleae Cortex did not have parenchymatous cell in the phloem; instead, stone cells including much square crystal of calcium oxalate were distributed around fiber bundle, and the parenchymatous cell included much druse crystal of calcium oxalate. 2) In both the Ulmi Cortex and Hemipteleae Cortex, rhytidome was observed in trunk bark, but not in root bark, but in the parenchymatous cell of the root bark of the Ulmi Cortex contained starch grain. 2. Flour States 1) In the flour of root bark of the Ulmi Cortex, a large parenchymatous cell was observed. However, in the flour of trunk bark and root bark of Hemipteleae Cortex, no parenchymatous eel was found; instead, stone cell including square crystal of calcium oxalate and druse crystal of calcium oxalate were observed. 2) There was no remarkable difference between the trunk bark and root bark of Hemipteleae Cortex. However, starch grain was contained in the parenchymatous cell of the root bark of Ulmi Cortex but not in the trunk bark of it. Conclusions : There were some morphological differences in external, internal, and flour parts of Ulmi Cortex and Hemipteleae Cortex. In particular, there was a morphological difference in flour states between the trunk bark and root bark of Ulmi Cortex, it is possible to use microscope to distinguish their flour states.

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Morphologic Changes of L5 Root at Coronal Source Images of MR Myelography in Cases of Foraminal or Extraforaminal Compression

  • Kim, Soo-Beom;Jang, Jee-Soo;Lee, Sang-Ho
    • Journal of Korean Neurosurgical Society
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    • 제46권1호
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    • pp.11-15
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    • 2009
  • Objective: Two findings easily found at coronal source images of MR myelography (MRM) were evaluated : dorsal root ganglion (DRG) swelling and running course abnormality (RCA) of L5 exiting root at foramen or extraforamen. We tried to find the sensitivity of each finding when root was compressed. Methods: From 2004 July to 2006, one hundred and ten patients underwent one side paraspinal decompression for their L5 root foraminal or extraforaminal compression at L5-S1 level. All kinds of conservative treatments failed to improve leg symptom for several months. Before surgery, MRI, CT and MRM were done. Retrospective radiologic analysis for their preoperative MRM coronal source images was done to specify root compression sites and L5 root morphologic changes. Results: DRG swelling was found in 66 (60%) of 110 patients. DRG swelling has statistically valuable meaning in foraminal root compression (chi-square test, p<0.0001). Seventy-two (66%) in 110 patients showed abnormal alteration of running course. Abnormal running course has statistically valuable meaning in foraminal or extraforaminal root compression (chi-square test, p<0.0001). Conclusion: Three-dimensional MRM provides precise thin sliced coronal images which are most close to real operative views. DRG swelling and running course abnormality of L5 exiting root are two useful findings in diagnosing L5 root compression at L5-S1 foramen or extraforamen. MRM is thought to provide additional diagnostic accuracy expecially in L5-S1 foraminal and extraforaminal area.

Influence of Initial Seedling Size and Root Pruning Intensity on Growth of Transplanting Seedling of Quercus acutissma

  • Na, Sung-Joon;Lee, Do-Hyung;Kim, In-Sik
    • 한국자원식물학회지
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    • 제26권6호
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    • pp.709-717
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    • 2013
  • The objective of this study was to examine the effect of root pruning intensity in combination with different initial seedling size on the growth of transplanting seedlings of Quercus acutissima. One-year-old seedlings were divided into three groups depending on their height, i.e. small (< 15 cm), medium (25-35 cm) and large size (35 cm <). Root of seedlings was pruned by three intensity such as, leaving 5 cm (severe), 10 cm (medium) and 15 cm (light) of taproot from the root-collar. After one year, we investigated survival rate, height and root-collar diameter (RCD) increment and final shoot dry weight. Also we measured characteristics of newly developed lateral roots such as number, total length, dry weight and diameter. Severe root pruning showed the lowest survival rate in all seedling size. Height increment, RCD increment and shoot dry weight were decreased with increasing intensity of root pruning. Seedlings of medium and light root pruning showed similar above-ground growth and dry weight of lateral roots. More large seedlings showed good survival rate, height increment and final shoot dry mass in all root pruning intensity. Therefore, one-year-old seedlings of Q. acutissima should be pruned taproot by 10 cm and transplanted to obtain excellent performance and increase the efficiency of transplanting work. Based on the findings of this study, it is important that applying to different root pruning intensity depending on initial seedling size for producing 2-year-old seedlings with excellent growth and high quality.

확장된 근궤적법을 이용한 PI 제어기 설계 방법 (PI Controller Design Method by an Extension of Root-Locus Technique)

  • 권민희;장혁준
    • 제어로봇시스템학회논문지
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    • 제22권2호
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    • pp.126-132
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    • 2016
  • The root-locus method is often employed when a controller is designed to find controller gain. It is usually used to determine one parameter gain while most controllers for industrial applications have more than one controller gain. For example PID controller has three controller gains, i.e. P, I, and D gains. Thus the conventional root-locus technique cannot complete the design of a controller with more than one controller gain. One way to overcome this drawback has been to apply the root-locus technique for one parameter while other parameters are assumed to be proportional to the parameter or to be constant. However this approach could lead to limited performance of the controller and if we try to adjust the proportional ratio or constants then it could be a long and tedious process of trial and error. Thus it is required to find an effective method for the root-locus technique to design controllers with more than one parameter. To this end this paper proposes an extended root-locus method for controllers with two parameters. In this paper Matlab is used as a computation tool to show the effectiveness of our method by solving examples numerically. As a result we obtained an extended root-locus illustrated in two-dimensional space for a control system with two parameters. The paper then presents how to find two controller gains based on this result of the extended root-locus. The main idea is that we can find the parameters by approaching the desired poles. It is expected that the proposed idea will help control engineers to easily design control systems using the root-locus technique, resulting in more accurate and faster control systems. Note that the extended root-locus idea can be applied to controller design problems with multiple parameters.