• 제목/요약/키워드: L-index

검색결과 3,084건 처리시간 0.029초

DVH를 이용한 선량 균등률 및 덮임률 지수에 관한 연구 (A Simple Scoring Method to Calculate the Homogeneity and Coverage Indices of Dose Volume Histogram)

  • 윤명근;박성용;신동호;박중헌;이세병;김대용;김주영;조관호
    • 한국의학물리학회지:의학물리
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    • 제17권1호
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    • pp.6-16
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    • 2006
  • 본 연구의 목적은 세기변조 방사선 치료법(IMRT)에 의해 만들어진 DVH를 이용하여 선량의 균등률(homogeneity) 및 덮임률(coverage) 지수를 구하는 간편한 방법을 제시하는 데 있다. 새로 개발된 지수들은 DVH 곡선을 수학적으로 계단 함수에 fitting 함으로써 구해졌다. 새로 제안된 지수 l는 종양에 대한 선량의 덮임률을 잘 나타내고 있으며 이 지수가 작으면 작을수록 더 좋은 덮임률을 보여주고 있다. 또한 종양의 균등률 지수로 제안된 n 지수는 기존에 사용되고 있는 균등률 지수들보다 좀 더 정확하게 선량의 균등성을 나태내고 있음을 확인하였다. 이들 지수를 이용하여 치료계획에 바탕이 되는 토대를 제시하였으며 여기에서 제안된 지수들이 선량의 균등성과 덮임성에 대해 매우 효과적인 방법이 될 수 있음을 보여주고 있다.

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Use of Cardiac Computed Tomography for Ventricular Volumetry in Late Postoperative Patients with Tetralogy of Fallot

  • Kim, Ho Jin;Mun, Da Na;Goo, Hyun Woo;Yun, Tae-Jin
    • Journal of Chest Surgery
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    • 제50권2호
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    • pp.71-77
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    • 2017
  • Background: Cardiac computed tomography (CT) has emerged as an alternative to magnetic resonance imaging (MRI) for ventricular volumetry. However, the clinical use of cardiac CT requires external validation. Methods: Both cardiac CT and MRI were performed prior to pulmonary valve implantation (PVI) in 11 patients (median age, 19 years) who had undergone total correction of tetralogy of Fallot during infancy. The simplified contouring method (MRI) and semiautomatic 3-dimensional region-growing method (CT) were used to measure ventricular volumes. Results: All volumetric indices measured by CT and MRI generally correlated well with each other, except for the left ventricular end-systolic volume index (LV-ESVI), which showed the following correlations with the other indices: the right ventricular end-diastolic volume index (RV-EDVI) (r=0.88, p<0.001), the right ventricular end-systolic volume index (RV-ESVI) (r=0.84, p=0.001), the left ventricular end-diastolic volume index (LV-EDVI) (r=0.90, p=0.001), and the LV-ESVI (r=0.55, p=0.079). While the EDVIs measured by CT were significantly larger than those measured by MRI (median RV-EDVI: $197mL/m^2$ vs. $175mL/m^2$, p=0.008; median LV-EDVI: $94mL/m^2$ vs. $92mL/m^2$, p=0.026), no significant differences were found for the RV-ESVI or LV-ESVI. Conclusion: The EDVIs measured by cardiac CT were greater than those measured by MRI, whereas the ESVIs measured by CT and MRI were comparable. The volumetric characteristics of these 2 diagnostic modalities should be taken into account when indications for late PVI after tetralogy of Fallot repair are assessed.

붉은쏨뱅이(Sebastiscus tertius)의 생식 주기 (Reproductive Cycle of the Red Marbled Rockfish Sebastiscus tertius)

  • 임상구;김광수;김철원;김정우
    • 한국수산과학회지
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    • 제44권6호
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    • pp.701-708
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    • 2011
  • The aim of the present study was to analyze the reductive cycle of the red marbled rockfish Sebastiscus tertius. The analysis was based on annual changes in the gonadosomatic index (GSI), the hepatosomatic index (HSI), histology of the gonadal structure, and plasma sex steroid hormone levels of adult fish from April 1997 to April 1998. GSI of females began to increase in February and peaked ($10.8{\pm}2.72$) in May. HIS levels ($3.41{\pm}0.49$) peaked in February and elevated plasma steroid hormones ($1.47{\pm}0.75$ ng/mL for estradiol-$17{\beta}$ ($E_2$) and $230.7{\pm}27.6$ pg/mL for testosterone (T)) were observed in April. However, in male fish, GSI levels started to increase in August and remained high until November ($0.21{\pm}0.05$). T levels were was also elevated in August and peaked in October ($188.1{\pm}43.5$ pg/mL) and November ($186.8{\pm}28.0$ pg/mL), but started to decline 1 month than the GSI. These results suggest that female ovoviviparious periods span from April to June and amle mating periods occur from November to February.

씨앗발아 및 발아지수에 근거한 나노입자 독성평가 (Toxicity Assessment of Nanopariticles Based on Seed Germination and Germination Index)

  • 구본우;공인철
    • 대한환경공학회지
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    • 제36권6호
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    • pp.396-401
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    • 2014
  • 나노물질은 다양한 분야에 널리 사용되고 있다. 본 연구에서는 Lactuca(상추)와 Raphanus(알타리무) 씨앗의 발아와 발아지수에 금속산화물 나노입자(CuO, NiO, $Fe_2O_3$, $Co_3O_4$, $TiO_2$, ZnO)가 미치는 영향을 조사하였다. 용액상 노출에서 CuO가 가장 큰 영향을 나타내었으며, 발아와 발아지수의 $EC_{50}$는 각 0.46 mg/L와 0.37%로 조사되었다. 씨앗 이용 식물독성 측정에서 상추가 알타리무보다 나노입자 노출에 대해 더욱 민감한 반응을 나타내었다. 일반적으로 나노입자의 씨앗발아와 발아지수에 근거한 영향은 다음의 순서로 조사되었다: CuO > ZnO >NiO > $TiO_2$, $Fe_2O_3$, $Co_3O_4$. 특히 $TiO_2$, $Fe_2O_3$$Co_3O_4$는 최대 노출 농도 1,000 mg/L 농도에서도 뚜렷한 영향을 나타내지 않았다.

The Effects of Dietary Supplementation of L-carnitine and Humic Substances on Performance, Egg Traits and Blood Parameters in Laying Hens

  • Yalcin, Sakine;Ergun, Ahmet;Ozsoy, Bulent;Yalcin, Suzan;Erol, Handan;Onbasilar, Ilyas
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권10호
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    • pp.1478-1483
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    • 2006
  • This experiment was carried out to determine the effects of supplementation of L-carnitine and humic substances alone or in combination in laying hen diets on performance, egg traits and blood parameters. A total of 180 IGH type brown laying hens aged 22 weeks were employed in a completely randomized block design with one control group and three treatment groups. Each group was divided into five replicates as subgroups, each comprising 9 hens. The diets of the first, second and third treatment groups were supplemented with 0.1 g/kg L-carnitine, 1.5 g/kg humic substances (Farmagulator$^{(R)}$ Dry Plus) and 0.1 g/kg L-carnitine+1.5 g/kg humic substances, respectively. The experimental period lasted 18 weeks. Feeding supplemental carnitine, humic substances or carnitine+humic substances resulted in increases in body weight gain (p<0.05). Dietary treatments did not significantly affect daily feed intake, daily metabolizable energy intake, egg production, egg weight, feed efficiency, mortality, egg shape index, egg breaking strength, egg shell thickness, egg albumen index, egg yolk index, egg Haugh unit and the percentages of egg shell, albumen and yolk. Supplementation of humic substances reduced egg yolk cholesterol as mg per g yolk and mg per yolk (p<0.05). Blood serum parameters were not affected by the supplementation of carnitine, humic substances or carnitine+humic substances. The results in this study demonstrated that humic substances supplementation reduced egg cholesterol without adverse effects on performance, egg traits and blood parameters of laying hens. It was concluded that the usage of L-carnitine alone or in combination with humic substances in diets had no beneficial effects in laying hens.

고속 통신용 DFB 레이저의 빔 분포 해석 (Beam Profile Analysis of DFB Laser for High Speed Communications)

  • 권기영
    • 문화기술의 융합
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    • 제6권3호
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    • pp.419-425
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    • 2020
  • 본 연구에서는 무반사 코팅을 하지 않은, 두 개의 거울 면을 갖는 1.55um 파장용 DFB(Distributed Feedback) 레이저에서 굴절률 격자와 이득 격자가 동시에 존재할 때, 해석 프로그램을 개발하여 종 방향으로 발진 모드의 빔 분포를 해석하였다. 굴절률 격자와 이득 격자가 거울 면에서 갖는 위상 값의 변화에 따라서, δL<0인 경우에 대하여, DFB 레이저의 발진 모드에 대한 발진 이득, 빔 분포 |R(z)|와 |S(z)|, 그리고 방사전력비 Pl/Pr를 비교 분석하였다. 거울 면에서의 격자 위상 값에 관계없이 발진 모드의 문턱 전류를 낮추고 주파수 안정성을 높이기 위해서는, κL이 8보다 커야한다.

ACCRETION-JET MODEL FOR THE HARD X-ray Γ - LX CORRELATION IN BLACK HOLE X-ray BINARIES

  • YANG, QI-XIANG;XIE, FU-GUO;YUAN, FENG;ZDZIARSKI, ANDRZEJ A.;GIERLINSKI, MAREK;HO, LUIS C.;YU, ZHAOLONG
    • 천문학논총
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    • 제30권2호
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    • pp.565-568
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    • 2015
  • In this work, we study the correlation between the photon index (${\Gamma}$) of the X-ray spectrum and the 2-10 keV X-ray luminosity ($L_X$) for black hole X-ray binaries (BHBs). The BHB sample is mainly from the quiescent, hard and intermediate states, with values of $L_X$ ranging from ${\sim}10^{30.5}$ to $10^{37.5}$ erg $s^{-1}$. We find that the photon index ${\Gamma}$ is positively or negatively correlated with the X-ray luminosity $L_X$, for $L_X$ above or below a critical value, ${\sim}10^{36.5}$ erg $s^{-1}$. This result is consistent with previous works. Moreover, when $L_X{\leq}{\sim}10^{33}$ erg $s^{-1}$, we found that the photon index is roughly independent of the X-ray luminosity. We interpret the above correlations in the framework of a coupled hot accretion flow - jet model. Besides, we also find that in the moderate-luminosity region, different sources may have different anti-correlation slopes, and we argue this diversity is caused by the different value of ${\delta}$, which describes the fraction of turbulent dissipation that directly heats electrons.

Factors Affecting Cage Obliquity and the Relationship between Cage Obliquity and Radiological Outcomes in Oblique Lateral Interbody Fusion at the L4-L5 Level

  • CheolWon Jang;SungHwan Hwang;Tae Kyung Jin;Hyung Jin Shin;Byung-Kyu Cho
    • Journal of Korean Neurosurgical Society
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    • 제66권6호
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    • pp.703-715
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    • 2023
  • Objective : This retrospective study investigated the factors that affect cage obliquity angle despite orthogonal maneuvers performed during oblique lateral interbody fusion (OLIF) and assessed the relationship between cage obliquity angle and radiological outcomes post-surgery. Methods : Twenty-nine males who underwent L4-L5 OLIF for lumbar degenerative disease between 2019 and 2021 with a followup duration greater than 12 months were analyzed. Radiological parameters were measured including psoas muscle volume, total psoas area index (total psoas muscle area [cm2]/height squared [m2]), distance from the iliac artery to the origin of the psoas muscle (DIAPM), angle between the origin of the psoas muscle and the center of the vertebral disc (APCVD), iliac crest height, disc height, lumbar flexibility (lumbar flexion angle minus extension angle), cage location ratio, cage-induced segmental lumbar lordosis (LL) (postoperative index level segmental LL minus used cage angle), foraminal height changes, fusion grade. Results : DIAPM, APCVD, iliac crest height, postoperative index level segmental LL, and cage-induced segmental LL were significantly correlated with OLIF cage obliquity angle. However, other radiological parameters did not correlate with cage obliquity. Based on multiple regression analysis, the predictive equation for the OLIF cage obliquity angle was 13.062-0.318×DIAPM+0.325×1APCVD+0.174×iliac crest height. The greater the cage obliquity, the smaller the segmental LL compared to the cage angle used. Conclusion : At the L4-L5 level, OLIF cage obliquity was affected by DIAPM, APCVD, and iliac crest height, and as the cage obliquity angle increases, LL agnle achievable by the used cage could not be obtained.

준임상적 갑상선 기능저하증과 혈청 지질 및 비만도의 상관관계 (Correlations of Subclinical Hypothyroidism with Serum Lipid Profiles and Obesity Index)

  • 김호준;박정현;이명종;박지훈;송미영
    • 대한한의학회지
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    • 제29권3호
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    • pp.38-49
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    • 2008
  • Objectives: Though overt thyroid dysfunction is well recognized to affect serum lipid profiles and obesity, there are conflicting reports on the effect of subclinical hypothyroidism on serum lipid profiles and obesity. In most reports, the definition of the upper normal limit of serum thyroid stimulation hormone (TSH) of 4.0${\sim}$5.0mU/L has been used to diagnose. However, recent studies have suggested a much lower TSH cut off with an upper limit of 2.5mU/L, because >95% of rigorously screened normal euthyroid volunteers had serum TSH values between 0.4 and 2.5mU/L. Therefore we defined subclinical hypothyroidism as a TSH level greater than 2.5mU/L. We sought to evaluate the correlations of subclinical hypothyroidism with obesity index and serum lipid profiles Methods: TSH levels were measured in 6190 men and 4223 women that participated in health examination and free T4, lipid profiles (total-cholesterol, triglyceride, LDL-C), and obesity index (body mass index, body fat, waist circumference, C-reactive protein) were also measured. Results: There were significant differences of triglyceride between subclinical hypothyroidism men and normal control subjects. In women, there were also significant differences of triglyceride and LDL-C between subclinical hypothyroidism and normal control subjects. Subclinical hypothyroidism women showed significant correlations of TSH with total cholesterol, LDL-C, triglyceride, and C-reactive protein. Subclinical hypothyroidism men and women with a TSH level 2.5${\sim}$4.0mU/L had significant differences of triglyceride and body fat. In men, there were significant differences of waist circumference andC-reactive protein. In women, there were significant differences of LDL-C. Conclusions: We have demonstrated correlations of subclinical hypothyroidism with serum lipid profiles and obesity index. These findings suggested that subclinical hypothyroidism people had an increased risk of dyslipidemia and obesity. Subclinical hypothyroidism people with a TSH level 2.5${\sim}$4.0mU/L may be also considered suspect since it may signal a case of evolving thyroid underactivity eligible to be prevented.

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전라남도에서 쯔쯔가무시병 매개체인 털진드기의 개체군 밀도에 관한 조사 (Population density of chigger mites, the vector of tsutsugamushi disease in Chollanam-do, Korea)

  • 송현제;김개환
    • Parasites, Hosts and Diseases
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    • 제34권1호
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    • pp.27-34
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    • 1996
  • 쯔쯔가무시병 환자가 집중 발생하는 10월부터 12월에 걸쳐 전라남도 6개 지역에서 들쥐와 들쥐에 기생하는 털진드기의 지리적 분포상에 대한 조사를 실시하여 다음과 같은 결과를 얻었다. Chemla식 wooden trap 814개를 사용하여 총 142마리의 들쉬를 포획하였는데 등줄쥐(Aponemr agrarius)가 131마리(92.3%)를 차지하여 절대 우점종이었고, 땃쥐(Crocidurarnwa)가 11마리로 7.7%였다 털진드기의 기생률은 들쥐 142마리 중 92마리에 털진드기가 기생하고 있어 69.0%이었고 총 10.532따리의 털진드기가 채집되어 74.2개체의 chi껄erindeu를 보였다. 이 중 등줄쥐는 73.3%의 기생률과 80.깊개체의 chiggor index를 땃쥐는 18.2%의 기생률과 05개체의 chiggor index를 보였다. 총 10.532개체 채집된 털찐드기는 4속 11종으로 동정되었는데 쯔쯔가무시병의 매개종인 Leptotrombidium pallidum과 L. scutellgre가 각각 8.038개체(76.3%)와 1.359개체 (12.9%)가 채집되어 우점종인 것으로 나타났다. 털진드기의 개체군 밀도에 대한 지리적 분포상이 종에 따라 심한 차이를 보여 각 조사지역마다 우점종이 다르게 나타났다. 장흥군 장흥읍과 보성군 복내면에서는 L. sueuwe가 8.9개체(100%)와 13.7개체(41.5%)로 절대 우점종이었고, 화순군 능주면과 곡성군 삼기면은 L. pallidum이 각각 191.9개페(88.8%). 46.0개페(59.2%)로 우점종이 었으며 함평군 월야면은 L. zetum이 5.1개체(77.3%) 담양군 담양읍은 L. pdpole가 2.6개체 (63.4%)로 우점종이었다. 지역별 털진드기의 밀도 비교에서 화순군 능주면이 216.2개체(62.4%) 로 가장 많은 개체수를 나타냈으며 그 다음으로 곡성군 삼기면의 77.7개체(22.4%)로 많았다.

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