• Title/Summary/Keyword: 초음파 속도

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A Study on the Diel Distribution and Activity Patterns of Fishes in the Korean Eastern Sea (한국 동해 어족생물의 일주기적 유영행동특성에 관한 연구)

  • 이대재;김성기
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.2
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    • pp.85-94
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    • 2001
  • The vertical distribution and activity patterns of fishes during the evening and morning transitions were investigated acoustically and by pelagic trawling on October 2-10, 1997 in the Korean Eastern Sea. The acoustic data were collected from four stations with a scientific echo sounder operating at a frequency of 38 kHz, and the echogram was used to analyze the diel vertical migration of fish. Biological sampling was accomplished by pelagic trawling to identify fish species recorded on the echograms, and the species and length compositions were investigated. Vertical profiles of water temperature, salinity at the trawl station were taken with a CTD system and were related to the diel movement and the depth distribution of fish. During the day, one group of fish mainly distributed above the depth layer of 50 m, the other group was at deeper water, approximately 250 m, but began to migrate toward the surface before sunset with a time difference. During the night, they were dispersed between the surface and the depth of 125 m. Just prior to sunrise, the scattering layer was divided with 2 groups and began to migrate downwards, respectively. Several trials of pelagic trawling for scattering layers suggest that the most dominant scatterer in the survey area of this study was Japanese flying squid, Todarodes pacificus..

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Liposome-Microencapsulation of Lysozyme and Its Stimulated Release (Lysozyme의 Liposome 미세캡슬화와 유출 촉진)

  • Kim, Tae-Jong;Kim, Young-Sook;Pyun, Yu-Ryang
    • Korean Journal of Food Science and Technology
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    • v.28 no.3
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    • pp.399-404
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    • 1996
  • Encapsulation of lysozyme using lecithin vesicles and its stimilated release properties were studied. Lecithin vesicles were prepared by the dehydration-rehydration (DR)method. The highest encapsulation efficiency (EE) value of 80.1% was obtained by sonicating the multilamellar vesicles (MLVs) at 100 KHz for 120 min in bath sonicator. The value of entrapment progressively increased with the concentration of lysozyme, while the EE value decreased with the increase of enzyme concentration up to 50mg per 100mg per 100mg of lecithin, and then became nearly constant. At the pH of 5.9, only a small amount of lysozyme was released from DR vesicles during incubation at $37^{\circ}C$ As the pH decreased to 3.0, lysozyme was released more rapidly. Lysozyme release was accelerated for 24h and reached a plateau after 72h incubation with 1% Tween 80, $Ca^{2+}$ gave a pulse-like-release in the first hour, which was followed by a slow release.

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Tuberous Sclerosis Complex with Crohn's Disease (크론병과 병발한 결절성경화증 1예)

  • Kim, Min Hee;Lee, Yoon Jin;Kim, Jae Young;Yi, Yoon Young;Kang, Joon Won
    • Journal of the Korean Child Neurology Society
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    • v.26 no.4
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    • pp.284-287
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    • 2018
  • Tuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by mutation of one of two genes, TSC1 (encoding hamartin, 9q34) and TSC2 (encoding tuberin, 16p13). It invades the central nervous system and various parts of the body, causing various symptoms. Crohn's disease (CD) is a chronic immune-mediated disease that has not been clearly elucidated. It is thought to be caused by an excessive immune response of the body to bacteria that normally exist in the digestive tract with genetic factors. No cases have been reported in which both of the above-mentioned diseases occurred simultaneously. We report a case of CD in a patient with TSC. A 12-year-old boy was brought to our hospital because of abdominal pain. Skin lesions were observed in the TSC. Fundus examination revealed a hamartoma in the right retina. Brain magnetic resonance imaging revealed a subendothelial giant cell astrocytoma (SEGA). On the basis of these findings, he was diagnosed as having TSC. Blood test results showed increased levels of inflammatory markers. On abdominal ultrasonography, his colon walls were observed to be thickened with increased vascularity of the proximal ascending colon, ileocecal valve, and terminal ileum. Colonoscopy revealed discontinuous ulcerations and inflammations of the ileum, IC valve, and cecum, similar to those found in CD. Everolimus was administered orally for the SEGA but was discontinued frequently owing to the exacerbation of CD. The possibility of CD should be kept in mind in patients with TSC considering to undergo treatment for SEGA.

A Study on Reaction of Metachromasy by means of Polyphenol Derivatives and Hematoxylin-Eosin in Vesicle of Dipalmitoyl Phosphatidyl Choline (Dipalmitoyl Phosphatidyl Choline의 Vesicle에서 Polyphenol Derivatives와 Hematoxylin-Eosin Stain에 의한 Metachromasy 반응에 관한 연구)

  • Kim, Ki-Jun;Sung, Wanmo;Kim, Joohan;Yoon, Sunghyun
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.1
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    • pp.348-354
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    • 2019
  • Dipalmitoyl phosphatidyl choline(DPPC), Polyphenol Derivatives, and Hematoxylin-Eosin were directly sonicated in acidic condition for 6 minutes to give clear stock solutions. Absorbtion properties of Polyphenol Derivatives in lecithin vesicle of Diphalmitoyl phosphatidyl choline system at $25^{\circ}C$ have been studied by absorbtion spectroscopy. The equilibrium of Polyphenol Derivatives between monomer and dimer in lecithin vesicles have been existed at low concentration of Polyphenol Derivatives, but oligomer has been formed in vesicle at high concentration of lecithin vesicles. By adding Bacteriorhodopsin(BR) to constant concentration of Polyphenol Derivatives decreased the absorbtion ratio(${\alpha}/{\beta}$) of Polyphenol Derivatives was increased during phase transition of dipalmitoyl phosphatidyl choline. In the presence of column eluted lamella vesicle and mixture of uni- and multilamella aggregates. The differences of rate between column eluted- and mixture were observed, therefore column eluted lamella reaction was represented more catalytic effect. The phase transition temperature of hydrolysis on Dipalmitoyl phosphatidyl choline and Polyphenol Derivatives were measured higher than it of Dipalmitoyl phosphatidyl choline and no Polyphenol Derivatives.

Evaluation and Physicochemical Property for Building Materials from the Japanese Ministry of General Affairs in Joseon Dynasty (일제강점기 조선통감부 건축재료의 물리화학적 특성과 평가)

  • Park, Seok Tae;Lee, Jeongeun;Lee, Chan Hee
    • Economic and Environmental Geology
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    • v.55 no.4
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    • pp.317-338
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    • 2022
  • Physicochemical characteristics and evaluation were studied by subdividing the concretes, bricks and earth pipes on the site of the Japanese Ministry of General Affairs in Joseon Dynasty, known as modern architecture, into three periods. Concretes showed similar specific gravity and absorption ratio, and large amounts of aggregates, quartz, feldspar, calcite and portlandite were detected. Porosity of the 1907 bricks were higher than those of 1910 and 1950 bricks. All earthen pipe is similar, but the earlier one was found to be more dense. Bricks and earthen pipes are dark red to brown in color within many cracks and pores, but the matrix of the earthen pipe is relatively homogeneous. Quartz, feldspar and hematite are detected in bricks, and mullite is confirmed with quartz and feldspar in earthen pipes, so it is interpreted that the materials have a firing temperature about 1,000 to 1,100℃. Concretes showed similar CaO content, but brick and earthen pipe had low SiO2 and high Al2O3 in the 1907 specimen. However, the materials have high genetic homogeneity based on similar geochemical behaviors. Ultrasonic velocity and rebound hardness of the concrete foundation differed due to the residual state, but indicated relatively weak physical properties. Converting the unconfined compressive strength, the 1st extended area had the highest mean values of 45.30 and 46.33 kgf/cm2, and the 2nd extended area showed the lowest mean values (20.05 and 24.76 kgf/cm2). In particular, the low CaO content and absorption ratio, the higher ultrasonic velocity and rebound hardness. It seems that the concrete used in the constructions of the Japanese Ministry of General Affairs in Joseon Dynasty had similar mixing characteristics and relatively constant specifications for each year. It is interpreted that the bricks and earthen pipes were through a similar manufacturing process using almost the same raw materials.

Predictive Value for Vesicoureteral Reflux in Children with Urinary Tract Infection (요로감염 환아에서 방광요관 역류를 예측할 수 있는 인자에 대한 연구)

  • Lee, Seung-Hyun;Noh, Sung-Hoon;Oh, Jeung-Eun;Kim, Min-Sun;Lee, Dae-Yeol
    • Childhood Kidney Diseases
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    • v.12 no.1
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    • pp.62-69
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    • 2008
  • Purpose: The most concerning issue in children with urinary tract infection(UTI) is the probability of underlying genitourinary anomalies and vesicoureteral reflux (VUR), which is frequently associated with renal scarring and eventually end-stage renal disease. Therefore, voiding cystourethrography(VCUG) is usually recommended at the earliest convenient time for children with UTI. However, VCUG is an invasive procedure that requires catheterization and exposure to X-ray. In this study, we aimed to determine the predictability of clinical, laboratory and imaging parameters for VUR in children with UTI. Methods: Data of children with bacteriologically proven UTI who underwent VCUG were evaluated retrospectively for clinical(age, gender, fever), laboratory(leukocytosis, ESR, CRP, pyuria, blood urea nitrogen, serum creatinine) and imaging(renal ultrasound and DMSA renal scan) findings. First, children with UTI were divided into two groups according to the presence of VUR as non-VUR group and with VUR group, and clinical, laboratory variables were compared between these groups. Second, patients who had VUR were reclassified as low-grade VUR(grade I-II) group and high-grade(grade III-V) VUR group according to grading of VUR, and clinical, laboratory and imaging variables were compared between these groups. Results: Among 410 children with UTI, 137 had VUR and 78 high-grade VUR. Fever, leukocytosis, ESR, CRP, pyuria were associated with VUR. In addition, abnormal findings of ultrasonography and DMSA renal scan were closely related to VUR. However, these clinical and laboratory variable in patients with high grade VUR were not different significantly, compared to those with low-grade VUR group. Conclusion: Fever, leukocytosis, ESR, CRP seems to be potentially useful predictors of VUR in pediatric patients with UTI. In addition, renal ultrasonography and DMSA renal scan findings supported the presence of VUR. Further study of these findings could limit unnecessary VCUG in patients with UTI.

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Assesment of Bone Strength Using a New Quantitative Ultrasound Device in Children with Renal Diseases (신질환 환아에서 초음파 골량측정법을 이용한 골상태 평가)

  • Kang Ju-Hyung;Shin Yun-Hye;Cho Nam-Han;Pai Ki-Soo
    • Childhood Kidney Diseases
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    • v.9 no.1
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    • pp.21-30
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    • 2005
  • Purpose : Metabolic bone diseases have been mai or problems in children with renal diseases and steroid treatment is the main precipitating factor reducing bone mineral density(BMD). This study was performed to assess the prevalence of osteoporosis and to evaluate the clinical factors associated with decreased BMD in children with renal diseases. Methods : Forty-four children with renal diseases who were diagnosed at the Pediatric no phrology division of Ajou University hospital since Oct. 1994 were included. Using a new quantitative ultrasound device, BMD and the prevalence of osteoporosis were evaluated. The clinical and serological data were analyzed in association with decreased BMD. Results : A total of 44 patients were evaluated. The age at initial diagnosis was 6.7$\pm$4.2 years. At the time of evaluation, the chronological and bone age was 9.3$\pm$4.2 years and 8.2 $\pm$ 4.6 years, respectively. The renal diseases included nephrotic syndrome 24(54.5%), Henoch Schonlein purpura nephritis 7(15.9%), IgA nephropathy 6(13.9%), reflux nephropathy(RN) 2 (4.5%), and other renal disease 5(%). The prevalence of osteoporosis was 11%. There was no difference in the clinical factors between the long-term and the short-term treated steroid groups. Conclusion : The prevalence of osteoporosis was 12% in 44 children with renal diseases No significant factor was found in association with decreased BMD and there was no relationship between osteoporosis and steroid usage duration or cumulative dose. A new quantitative ultrasound, which is relatively easy to perform, especially in children, is expected to be in common use and will enable clinicians to evaluate metabolic bone disorders with ease.

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Clinical Significance of Electrolyte Imbalance in Pediatric Urinary Tract Infection (요로감염과 동반된 전해질 불균형의 임상적 의의)

  • Cho, Sea-Eun;Choi, Lim;Yim, Hyung-Eun;Yoo, Kee-Hwan;Hong, Young-Sook;Lee, Joo-Won
    • Childhood Kidney Diseases
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    • v.15 no.1
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    • pp.58-65
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    • 2011
  • Purpose: Some hormonal and electrolyte abnormalities have been reported in pediatric patients with urinary tract infection (UTI). This study aimed to investigate the relationships between the imbalance of electrolytes and the severity of infection and associated urologic anomalies in children with febrile UTI. Methods: We retrospectively reviewed 267 patients with febrile UTI who were admitted to Korea University Guro Hospital during the period from January, 2007 until February, 2010. According to the presence of hyponatremia or hyperkalemia, clinical parameters and associated renal anomalies, such as hydronephrosis, cortical defects and vesicoureteral reflux, were compared. Results: 42.7% of all patients had decreased concentration of serum sodium. In patients with decreased concentration of serum sodium, cortical defects were significantly increased compared to normal patients (40.4% vs. 14.4%, P <0.05). White blood cell (WBC) counts ($15,721{\pm}6,553/uL$ vs. $12,885{\pm}5,367/uL$, P <0.05), C-reactive protein (CRP) ($61.8{\pm}56.1$ mg/L, vs. $29.9{\pm}39.8$ mg/L, P <0.05), and erythrocyte sedimentation rate (ESR) ($43.9{\pm}34.3$ mm/hr vs. $27.4{\pm}26.8$ mm/hr, P <0.05) in peripheral blood showed significant increases in the group with decreased concentration of serum sodium. Duration of fever, presence of gastrointestinal symptom, the incidence of hydronephrosis and vesicoureteral reflux did not differ between the two groups. None of the patients had significant hyperkalemia. Conclusion : We suggest that decreased concentration of serum sodium in febrile UTI might be a helpful marker for leukocytosis and increased CRP and ESR in peripheral blood, and acute pyelonephritis.

Intermediate-term Result of Tricuspid Annuloplasty for Tricuspid Regurgitation Associated with Congenital Heart Disease in Adult (성인 선천성 심기형에 동반된 삼첨판막 폐쇄부전의 판막륜 성형술 후 중기성적)

  • Yun, Tae-Jin;Kim, Sang-Hwa;Lee, Jun-Wan;Park, Jeong-Jun;Song, Hyun;Lee, Jae-Won;Seo, Dong-Man;Song, Meong-Gun;Song, Jong-Min;Kang, Duck-Hyun;Song, Jae-Kwan;Jang, Wan-Sook;Kim, Young-Hwue;Ko, Jae-Kon;Park, In-Sook
    • Journal of Chest Surgery
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    • v.36 no.3
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    • pp.136-141
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    • 2003
  • We assessed the intermediate-term result of tricuspid annuloplasty (TAP) for tricuspid valve regurgitation (TR) associated with congenital heart disease in adults. Risk factors for residual TR were also analysed. Material and Method: From August 1989 to June 2001, seventy three adult patients, 51 females and 22 males, underwent TAP for TR associated with various congenital heart disease. Their age ranged from 46 years to 73 years (mean:43). Associated heart anomalies were atrial septal defect (55), ventricular septal defect (6), partial anomalous pulmonary venous return (4) and others (8). Preoperative and post-operative TR velocities were 3.25 m/sec and 2.56 m/sec respectively, and the types of TAP were De Vega in 43, Kay in 18 and Ring annuloplasty in 12. Postoperative follow-up duration was 2,347 patient-month (mean: 32.6 months), and 134 two-dimensional echocardiographic examinations were done during this period. Residual TR greater than III/IV was considered as TAP failure. Result: TAP failure was observed in 7 patients (9.6%), and one patient among them underwent tricuspid valve replacement. Risk factors for TAP failure were diagnosis other than atrial septal defect (p=0.001), preoperative (p=0.038) and postoperative (p=0.028) high TR velocity. There was no statistical significance in terms of TAP methods. Conclusion: Careful evaluation of valve morphology and aggressive surgical intervention are mandatory for the repair of TR with preoperative or residual RV pressure overload.

Distinction and Tracking of Multiple Pingers Using a Single Frequency (단일 주파수에 의한 복수의 초음파 핑거의 식별 및 추적)

  • 신현옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.4
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    • pp.360-364
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    • 1990
  • To testy time division scheme, we performed some experiments in a circular water tank(13m in diameter and 1m deep). A result of that is shown in figure 4. The 2-dimensional position of the pinger was calculated by the method of hyperbolic line of position calculation. The resolution of the time difference on the base line is 2.5cm. In experiments, the multiple pingers of a single frequency were distinguished and tracked successfully. When the experiment is carried out in the water tank, some multi-path pulses always occur. To delete it, several 10 ms of time delay is inserted onto the program after a group of the normal signals are received. Some normal pulses are not received by the time delay, however there is no problem, practically, for the distinction and the tracking of the pulse. In 2-dimensional positioning, the pinger position can be calculated with three hydrophones. However, if four hydrophones are available, the positioning accuracy will be higher than three hydrophones only by some techniques. Another good feature of the use of four hydrophones is that the positioning of the pinger is capable if a hydrophone fails in receiving them. We also tested this distinguishing method in the field using another type pingers(APPENDIXA).

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