Differentiating Benign from Malignant Bone Tumors Using Fluid-Fluid Level Features on Magnetic Resonance Imaging

Hong Yu,Jian-Ling Cui,Sheng-Jie Cui,Ying-Cai Sun,Feng-Zhen Cui 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.6

Objective: To analyze different fluid-fluid level features between benign and malignant bone tumors on magnetic resonance imaging (MRI). Materials and Methods: This study was approved by the hospital ethics committee. We retrospectively analyzed 47 patients diagnosed with benign (n = 29) or malignant (n = 18) bone tumors demonstrated by biopsy/surgical resection and who showed the intratumoral fluid-fluid level on pre-surgical MRI. The maximum length of the largest fluid-fluid level and the ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane were investigated for use in distinguishing benign from malignant tumors using the Mann-Whitney U-test and a receiver operating characteristic (ROC) analysis. Fluid-fluid level was categorized by quantity (multiple vs. single fluid-fluid level) and by T1-weighted image signal pattern (high/low, low/high, and undifferentiated), and the findings were compared between the benign and malignant groups using the χ2 test. Results: The ratio of the maximum length of the largest fluid-fluid level to the maximum length of bone tumors in the sagittal plane that allowed statistically significant differentiation between benign and malignant bone tumors had an area under the ROC curve of 0.758 (95% confidence interval, 0.616–0.899). A cutoff value of 41.5% (higher value suggests a benign tumor) had sensitivity of 73% and specificity of 83%. Conclusion: The ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane may be useful to differentiate benign from malignant bone tumors.

Two-fluid non-Newtonian models for blood flow in catheterized arteries - A comparative study

D. S. Sankar,Usik Lee 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.9

Steady flow of blood through catheterized arteries is studied by assuming the blood as a two-fluid model with the suspension of all the erythrocytes in the core region as a non-Newtonian fluid and the plasma in the peripheral layer as a Newtonian fluid. The non-Newtonian fluid in the core region of the artery is modeled as (i) Casson fluid and (ii) Herschel-Bulkley fluid. The expressions for the shear stress, velocity, flow rate, wall shear stress and flow resistance, obtained by Sankar and Lee (2008a, 2008b) for the two-fluid Casson model and two-fluid Herschel-Bulkley model are used to get the data for comparison. It is noticed that the plug flow velocity, velocity distribution and flow rate for the two-fluid H-B model are considerably higher than that of the two-fluid Casson model for a given set of values of the parameters. Further, it is found that the resistance to flow is significantly lower for the two-fluid H-B model than that of the two-fluid Casson model. Thus, the two-fluid H-B model is more useful than the two-fluid Casson model to analyze the blood flow through catheterized arteries.

Non-uniform Distribution of Magnetic Fluid in Multistage Magnetic Fluid Seals

Wang Zhongzhong,Li Decai,Zhou Jing 한국자기학회 2017 Journal of Magnetics Vol.22 No.2

Magnetic fluid, a new type of magnetic material, is a colloidal liquid constituted of nano-scale ferromagnetic particles suspended in carrier fluid. Magnetic fluid sealing is one of the most successful applications of magnetic fluid. As a new type of seal offering the advantages of no leakage, long life and high reliability, the magnetic fluid seal has been widely utilized under vacuum- and low-pressure-differential conditions. In practical applications, for improved pressure capacity, a multistage sealing structure is always used. However, in engineering applications, a uniform distribution of magnetic fluid under each tooth often cannot be achieved, which problem weakens the overall pressure capacity of the seals. In order to improve the pressure capacity of magnetic fluid seals and broaden their applications, the present study theoretically and experimentally analyzed the degree of non-uniform distribution of multistage magnetic fluid seals. A mathematical model reflecting the relationship between the pressure capacity and the distribution of magnetic fluid under a single tooth was constructed, and a formula showing the relationship between the volume of magnetic fluid and its contact width with the shaft was derived. Furthermore, the relationship of magnetic fluid volume to capacity was analyzed. Thereby, the causes of non-uniform distribution could be verified: injection of magnetic fluid; the assembly of magnetic fluid seals; the change of magnetic fluid silhouette under pressure loading; the magnetic fluid sealing mechanism of pressure transmission, and seal failure. In consideration of these causes, methods to improve the pressure capacity of magnetic fluid seals was devised (and is herein proposed).

세포원침법을 이용하여 Wright 염색 후 악성종양 세포 검출 경험

이영진,박도심,조지현 대한임상검사정도관리학회 2001 臨床檢査와 精度管理 Vol.23 No.1

여러가지 자기장 배치 기법에 따른 자성유체 속도 및 압력 분포에 관한 수치해석적 연구

송준호(Joon-Ho Song),이육형(Yuk-Hyung Lee),배형섭(Hyung-Sub Bae) 한국기계가공학회 2008 한국기계가공학회지 Vol.7 No.2

In this paper, we analyzed the dynamic behavior of magnetic fluid in a circular pipe with multiple permanent magnets. Magnetic fluid react on magnetic field against the normal fluid. In other words, magnetic fluid flow has the electromagnetism and fluid mechanics. So magnetic fluids has studied about the fluids properties and experiment. In this paper we studied the magnetic fluids velocity and pressure distribution for the novel type actuator. Because the velocity and pressure distribution is the important element of the magnetic fluids flow. First, we analyzed the Maxwell equation for the multiple permanent magnet and then concluded the governing equations for the magnetic fluid flow using the equation of Navier-Stokes. And, we simulated the dynamic behavior of magnetic fluid flow using the FEM(Finite Element Method). And we illustrated the relation between magnetic field and dynamic behavior of magnetic fluid flow.

Evaluation of Matrix Effect in Body Fluid Chemistry on Roche Cobas 8000 c702 System

서종도,이지교,김승환,남영원,이준희,이경훈,송정한,송상훈 대한진단검사의학회 2021 Laboratory Medicine Online Vol.11 No.4

Background: Analysis of body fluids aids in diagnosis and monitoring disease. However, only a few testing platforms and reagents have been validated for a range of body fluids or analytes. In this study, we evaluated a testing system, which has been approved for blood samples, in analyzing body fluid specimens upon matrix mixing. Methods: Serum and body fluid samples, including cerebrospinal fluid (CSF), ascites, pleural fluid, amniotic fluid, and synovial fluid, were mixed, then the matrix effect and linearity for major analytes, namely amylase, chloride, glucose, LDH, and protein were evaluated (N = 30 serum-body fluid pairs) on the Cobas 8000 c702. The obtained data was compared with that of open reagents evaluated on the Architect c16000. Results: For all analyte-body fluid pairs, the mean percent recovery ranged from 98.4% to 101.7%, and this was within the acceptable range for matrix effect. In the linearity test, maximum non-linearity for each analyte-body fluid pair ranged from -5.0% to +4.2%. In interference test, proteins showed positive hemolytic, icteric, and lipemic interference in CSF and hemolytic interference in amniotic fluid. There was no significant interference in the other analyte-body fluid pairs. Results were highly correlated between the Cobas 8000 c702 and the Architect c16000 system. Conclusions: Our findings revealed that the matrix effect of major analytes in body fluid specimens can be excluded and they also validated the linearity of the analytes in the body fluid specimens. Therefore, reagents specified for blood samples can be readily adopted for the analysis of body fluids.

체외배양 기술로 생산된 초기배에 의한 한우 송아지 생산 기술 개발 I. 소 난포액의 Fraction이 난모세포의 성숙, 수정 및 배발생에 미치는 효과

서경덕,김호중,김광식 한국동물번식학회 1997 Reproductive & developmental biology Vol.21 No.2

We determined the effects of follicular fluid fractions in the maturation medium on bovine oocyte maturation, fertilization and subsequent development, as well as on number of cells in blastocysts following culture. Follicular fluid and oocytes from bovine follicles less than 5 mm in diameter were collected from the ovaries of slaughtered cows. Follicular fluid was separated into different molecular weight fractions by untrafiltration through a membrane using a centrifuge at 500$\times$g, for 2h. For the maturation medium, follicular fluid fractions (30%, v/v), whole fluid (30%) or PVP(3mg/ml) were added to TCM 199(0.1$\mu\textrm{g}$/ml estradiol-17$\beta$, 100IU hCG). After maturation for 24h, oocytes were fertilized in vitro with bull frozen-thawed spermatozoa and cultured on a monolayer of granulosa cells for 9 days after fertilization. There were no differences in maturation rates or fertilization rates among any maturation conditions. The rates of development to >2-cell stage of the oocytes were significantly decreased when fraction of follicular fluid below 10,000 MW were added into maturation medium, compared with control and fraction above 10,000 MW(26.0% vs 40.8% to 64.0%, respectveily. p<0.01). Likewise, the rates of development to blastocysts of fertilized oocytes were significantly decreased in maturation medium containing fraction of follicular fluid (<10,000 MW). The average cell number of blastocysts derived from oocytes that matured in the fraction(>10,000 MW) of follicular fluid was 154.7$\pm$13.7. These embryos contained more cells than those matured in whole follicular fluid, or the fraction(<10, 000 MW) of follicular fluid or control(107.0$\pm$8.4, 91.8$\pm$11.8 and 95.8$\pm$6.2, respectively). In conclusion, we found that fractions of follicular fluid contained factors stimulating or inhibiting oocyte cytoplasmic matruation. These suggest that a factor(s) inducing cytoplasmic maturation of oocytes may exist in >10,000 MW fraction of follicular fluid.

사각형 구조물에 저장된 유체의 동적거동에 유체높이와 구조물 폭의 비가 미치는 영향

박건,윤형철,홍기남 한국구조물진단유지관리공학회 2020 한국구조물진단유지관리공학회 논문집 Vol.24 No.5

In the case of an earthquake, the fluid storage structure generates hydraulic pressure due to the fluctuation of the fluid. At this time, the hydraulic pressure of the fluid changes not only the peaked acceleration of the earthquake but also the sloshing height of the fluid free water surface. Factors influencing this change in load include the shape of the seismic wave, the maximum seismic strength, the size of the fluid storage structure, the width of the structure, and the height of the fluid. In this study, the effect of the ratio between the height of the fluid and the width of the structure was investigated on the fluctuation characteristics of the fluid. 200mm and 140mm of fluid were placed in a water storage tank with a width of 500mm, and a real seismic wave was applied to measure the shape of the fluctuation of the fluid free water surface. The similarity between the experiment and the analysis was verified through the S.P.H(Smoothed Particle Hydrodynamic) technique, one of the numerical analysis techniques. It was confirmed that the free water surface of the fluid showed a similar shape, through comparison of experiment and analysis. And based on this results, SPH technique was applied to analyze the fluctuation shape of the fluid free water surface while varying the ratio between the fluid height and the structure width. An equation to predict the maximum and minimum heights of the fluid free water surface during an earthquake was proposed, and it was confirmed that the error between the maximum and minimum heights of the fluid free water surface predicted by the proposed equation was within a maximum of 3%. 유체 저장 구조물은 지진 시 유체의 출렁임에 의해 동수압이 발생한다. 이 때, 유체의 동수압은 지진의 강도뿐만 아니라 유체 자유수면의 출렁임 높이(sloshing height)에 의해서도 변화한다. 이러한 하중 변화에 영향을 미치는 인자로는 지진파의 형상, 최대지진강도, 유체 저장 구조물의 크기, 구조물의 폭, 유체의 높이 등이 있으며, 본 연구에서는 유체높이와 구조물 폭의 비가 유체의 출렁임 특성에 미치는 영향을 규명하고자 한다. 이를 위하여 구조물의 폭이 500mm인 수조에 구조물의 전체 높이 대비 50%인 200mm와 35%인 140mm의 유체를 담아 실지진파를 적용시켜 유체 자유수면의 출렁임 높이를 측정하였다. 또한 수치해석기법 중 하나인 SPH기법을 통하여 실험과 해석의 유사성을 검증하였다. 실험과 해석의 비교를 통하여 유체의 자유 수면이 유사한 형상을 나타냄을 확인하였으며, 이를 바탕으로 SPH기법을 적용하여 유체높이와 구조물 폭의 비를 다양하게 변화시키면서 유체 자유수면의 출렁임 형상을 분석하였다. 이상의 결과를 바탕으로 지진시 유체 자유수면의 최대높이 및 최소높이를 예측할 수 있는 식을 제안하였으며, 제안식에 의해 예측된 유체 자유수면의 최대 높이 및 최소 높이의 오차는 최대 3% 이내임을 확인하였다.

Effect of Changing Amniotic Fluid Osmolarity on the $Li^+$ Transport Through the Membrane Surrounding Amniotic Fluid in the Rabbit

Chang, Jin-Keun,Lee, Sang-Jin,Sung, Ho-Kyung The Korean Physiological Society 1993 대한생리학회지 Vol.27 No.1

To study the regulation of amniotic fluid volume and electrolyte concentration by the Membranes surrounding the amniotic fluid, the rate of $Li^+$ disappearance from amniotic sac of expired fetuses were examined while increasing the amniotic volume and osmolarity in rabbits. After intraamniotic injection of 1 ml isosmotic saline (about 20% of the amniotic fluid volume) containing 15 mM LiCl and 0.5 g/L Censored, the time courses of $Li^+$ and Censored disappearance were determined. From there the $Li^+$ clearance through the extrafetal routes was estimated and compared with that obtained from living fetuses. The volume, $Na^+$ concentration and osmolarity of amniotic fluid were measured and their relationships with $Li^+$ disappearance were evaluated. The fellowing results were obtained: 1. The rate of disappearance from amniotic fluid of living fetuses during the first 30 minutes was strikingly higher for $Li^+$ than for Censored, suggesting that extrafetal routes exist. At 60 and 90 minutes, however, the disappearance rate of $Li^+$ was less than that of Censored, suggesting the possibility of $Li^+$ reentry through fetal urination. 2. The disappearance of $Li^+$ from the amniotic fluid of the expired fetus was substantial, although lower than that of living fetuses, throughout the experimental period. 3. The $Na^+$ concentration and the osmolarity of the amniotic fluid of expired fetus measured 30 minutes after an intraamniotic injection of isoosmotic saline showed wide variation, but thereafter they changed gradually towards the normal extracellular fluid level. 4. When the amniotic fluid was iso- or hyposmolar, the rate of $Li^+$ disappearance from the amniotic fluid of the expired fetuses showed little variation. However, when the amniotic fluid was hyperosmolar, the rate at 30 minutes was markedly lower than those of isosmotic or hyposmotic amniotic fluid. At 90 minutes, the rate of $Li^+$ disappearance in hyperosmolar fluid reached a similar level to the rate in isosmolar fluid. 5. The intraamniotic injection of 400 mOsm/L saline solution decreased the disappearance rate of $Li^+$ from expired fetuses, while the injection of mannitol into the maternal vein induced no significant change. From these results it is concluded that: 1) a significant amount of $Li^+$ may leave the amniotic fluid via filtration through the membranes surrounding the amniotic fluid, 2) during hyperosmolar challenge to amniotic fluid, osmotic bulk flow might counteract the filterable loss, and 3) $Li^+$ disappearance might continue even after the volume and osmolarity of the amniotic fluid have recovered to control values.

Effect of Changing Amniotic Fluid Osmolarity on the Li⁺ Transport Through the Membrane Surrounding Amniotic Fluid in the Rabbit

Chang. Jin-Keun,Lee. Sang-Jin,Sung. Ho-Kyung 대한생리학회 1993 대한생리학회지 Vol.27 No.1

To study the regulation of amniotic fluid volume and electrolyte concentration by the Membranes surrounding the amniotic fluid, the rate of Li⁺ disappearance from amniotic sac of expired fetuses were examined while increasing the amniotic volume and osmolarity in rabbits. After intraamniotic injection of 1 ml isosmotic saline (about 20% of the amniotic fluid volume) containing 15 mM LiCl and 0.5 g/L Censored, the time courses of Li⁺ and Censored disappearance were determined. From there the Li⁺ clearance through the extrafetal routes was estimated and compared with that obtained from living fetuses. The volume, Na⁺ concentration and osmolarity of amniotic fluid were measured and their relationships with Li⁺ disappearance were evaluated. The fellowing results were obtained: 1. The rate of disappearance from amniotic fluid of living fetuses during the first 30 minutes was strikingly higher for Li⁺ than for Censored, suggesting that extrafetal routes exist. At 60 and 90 minutes, however, the disappearance rate of Li⁺ was less than that of Censored, suggesting the possibility of Li⁺ reentry through fetal urination. 2. The disappearance of Li⁺ from the amniotic fluid of the expired fetus was substantial, although lower than that of living fetuses, throughout the experimental period. 3. The Na⁺ concentration and the osmolarity of the amniotic fluid of expired fetus measured 30 minutes after an intraamniotic injection of isoosmotic saline showed wide variation, but thereafter they changed gradually towards the normal extracellular fluid level. 4. When the amniotic fluid was iso- or hyposmolar, the rate of Li⁺ disappearance from the amniotic fluid of the expired fetuses showed little variation. However, when the amniotic fluid was hyperosmolar, the rate at 30 minutes was markedly lower than those of isosmotic or hyposmotic amniotic fluid. At 90 minutes, the rate of Li⁺ disappearance in hyperosmolar fluid reached a similar level to the rate in isosmolar fluid. 5. The intraamniotic injection of 400 mOsm/L saline solution decreased the disappearance rate of Li⁺ from expired fetuses, while the injection of mannitol into the maternal vein induced no significant change. From these results it is concluded that: 1) a significant amount of Li⁺ may leave the amniotic fluid via filtration through the membranes surrounding the amniotic fluid, 2) during hyperosmolar challenge to amniotic fluid, osmotic bulk flow might counteract the filterable loss, and 3) Li⁺ disappearance might continue even after the volume and osmolarity of the amniotic fluid have recovered to control values.