• Title/Summary/Keyword: organ distribution

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Identification of frequency determining sound generating organ of cicadas with the Helmholtz resonator structure (헬름홀쯔 공명기 구조 매미 소리의 주파수 결정 발음기관 규명)

  • Yoon, Ki-sang;Cho, Se-hyun;Jung, Yoon-sang;Lee, Dong-hyun
    • The Journal of the Acoustical Society of Korea
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    • v.37 no.5
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    • pp.276-283
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    • 2018
  • The purpose of the study is to identify a sound generating organ that has a major influence on the central frequency of the cicadas with the Helmholtz resonator structure for the first time. The sound of cicadas Cryptotympana atrata and Hyalessa fuscata were recorded and analyzed, then the motion of the tymbals was analyzed with a high-speed camera to compare the relationship between the frequency of sound and the motion of the tymbals. As a result, there was little difference in the frequency distribution of calling song and scream for two species. The tymbals of C. atrata oscillated in three vibration modes, while those of H. fuscata oscillated in one mode. There was no difference in the frequency of both tymbals of both cicadas, and three vibration modes of C. atrata generated sound with different frequency bands. The frequency band of tymbals and the central frequency band of calling song were very similar. In conclusion, it is presumed that the frequency of the cicadas with the Helmholtz resonator structure was determined by mode frequency of the tymbals than resonance condition of the abdomen.

A Study on Effective Application of $Methylenediphosphonate-^{99m}Tc$ ($Methylenediphosphonate-^{99m}Tc$의 효과적 이용에 관한 연구)

  • Kim, Jae-Rok;Awh, Ok-Doo;Park, Kyung-Bae;Koo, Hyeon-Sook
    • The Korean Journal of Nuclear Medicine
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    • v.16 no.1
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    • pp.55-61
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    • 1982
  • Biodistribution studies has been carried out to elucidate the cause of poor bone imagings often encountered in using $methylenediphosphonate(MDP)-^{99m}Tc$ and to establish effective conditions in using the popular bone imaging agent. After 150 minutes from the I.V. injection of $MDP-^{99m}Tc$ to mice, the radioactivities accumulated at bone(B), liver(L), and stomach(S) were counted. The radiochemical purity (RCP), the volume, the radioactivity concentration and the amount of radioactivity of $MDP-^{99m}Tc$ were controlled. Data were expressed either in %cpm/g organ or % cpm/organ. The organ distribution ratios(B/L and B/S) were correlated with the RCP, the volume of injection, the radioactivity concentration etc. Results indicated that the RCP plays a major role in biodistributions. High radioactivity concentration and injection of a small amount is recommended. Negligible effect was observed with the amount of radioactivity. It has been confirmed that the up-to-date methods of RCP determinations cannot sensitively detect the sharply affecting trace impurities. A particular biodistribution pattern of crossed B/L and B/S lines was observed in case of using $MDP-^{99m}Tc$ of low RCP. In such a case, rather a higher dosage would be effective for improving the contrast between bone and liver.

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Effect of Vitamin E Supplementation on Lipid Distribution and Serum Insulin in Experimental Model Rats with Impaired Glucose Tolerance (내당능 장애 모델 흰쥐에서 Vitamin E의 과잉섭취가 지질 분포와 혈청 Insulin 농도변화에 미치는 영향)

  • 이영주
    • Journal of Nutrition and Health
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    • v.31 no.8
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    • pp.1226-1234
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    • 1998
  • The aim of the study was to determine whether vitamin E supplementation in three experimental model rats with impaired glucse tolerance could change serum insulin concentration and lipid distribution. The three groups were adult(AS) and neonatal (NS) streptozotocin-induced groups, and a high sucrose diet(HS) group. Each group was divided into control and vitamin E supplementatino groups at the age of 9 weeks. The level of vitamin E supplementation was 5g/kg diet. Blood and organ samples were taken at 5 and 10 weeks and were examined for changes in the level of serum insulin, glucose, lipids, liver lipids, and oxidative status. Vitamin E supplementation significantly reduced serum insulin in the HS group and caused the significant beneficial changes in serum lipids and triglycerides in As grouop at 10 weeks . In all groups, serum vitamin E was increased and malondialdehyde(MDA) in serumand liver were decreased significantly by vitamin E supplementation. The results suggest that vitamin E supplementation improves lipid distribution in adult streptozotocin-induced rats and serum insulin concentration in high sucrose diet-induced rats. Vitamin E might prevent on reduce oxidative injury in all experimental model rats with impaired glucose tolerance.

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A Clinical Evaluation of the Traumatic Sternal Fracture (외상성 흉골 골절에 대한 임상적 고찰)

  • Kim, Jae-Ryeon;Im, Jin-Su;Choe, Hyeong-Ho
    • Journal of Chest Surgery
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    • v.28 no.6
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    • pp.601-605
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    • 1995
  • Clinical evaluations were performed on 54 cases of the traumatic sternal fracture, those were admitted and treated at the department of Thoracic and Cardiovascular Surgery in Chosun University Hospital during the past 5 years period from January 1990 to December 1994. The frequency was about 7.8% of the nonpenetrating chest trauma. The ratio of male to female was 2 : 1 in male predominance. Average age was 45.7 years old and age distribution was from 18 to 80 years old. The most common cause in the sternal fracture were high decelerating injury[ 38 cases . The most common fracture site was sternal body. Associated intrathoracic organ injuries were cardiac contusion[11cases , hemopneumothorax and pulmonary contusion. Added, thoracic cage and extrathoracic organ injuries were rib fracture, head injuries, thoracic spinal fracture and long bone fracture. Abnormal ECG findings were sinus bradycardia[4 cases , sinus tachycardia[3 cases , bundle branch block, atrial fibrillaton, left ventricular hypertrophy and myocardial ischemia. The average days of admission was 19.1 days. All patients were treated with conservative treatment. The complications after treatment were atelectasis[2 cases ,empyema[1 cases , ARDS[1 cases .

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Evaluation of apoptosis after ionizing radiation in feeding and starving rats

  • Lee, Jae-Hyun;Cho, Kyung-Ja;Hong, Seok-Il;Park, Min-Kyung
    • Korean Journal of Veterinary Pathology
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    • v.2 no.1
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    • pp.37-46
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    • 1998
  • It has been known that $\gamma$-irradiation usually induces cell death in regenerating stem cell in normal tissues like skin, intestine and hematopoietic organ. The experiment were carried out to evaluate the early response of radiation injury in radiosensitive and intermediate radiosensitive tissues in feeding and starving rats with the doses of 3.5 and 7.0 Gy. The results of the study showed that the histological phenomenon was apoptosis in the doses of the radiation as the early response of tissue injury. Apoptosis were showed organ-specific and cellular specific responses suggesting that the selection of apoptosis be exactly focused on highly renewal organs and cells. It was interesting that the rats starved for 72 hours prior to irradiation induced less apoptosis in liver than fed rats. As for cellular responses it appeared that apoptotic cells were mostly distributed in ductal or periportal cells in liver of feeding rats unlikely in liver of Starving rots which showed no difference in zonal distribution. In salivary gland apoptotic cells in fed rats were highly induced in intercalating and ductal cell population than in acinar cell population although unlikely in starved rats. This study showed the value of apoptosis using the detection system of TUNEL for evaluating cellular damage after radiation injury and the diminished effect of starvation on cell damage after ionizing irradiation.

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Evaluation Internal Radiation Dose of Pediatric Patients during Medicine Tests Using Monte Carlo Simulation (몬테칼로 시뮬레이션을 이용한 소아 핵의학검사 시 인체내부 장기선량 평가)

  • Lee, Dong-yeon;Kang, Yeong-rok
    • Journal of radiological science and technology
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    • v.44 no.2
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    • pp.109-115
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    • 2021
  • In this study, a physical evaluation of internal radiation exposure in children was conducted using nuclear medicine test(Renal DTPA Dynamic Study) to simulate the distribution and effects of the radiation throughout the tracer kinetics over time. Monte Carlo simulations were performed to determine the internal medical radiation exposure during the tests and to provide basic data for medical radiation exposure management. Specifically, dose variability based on changes in the tracer kinetic was simulated over time. The internal exposure to the target organ (kidney) and other surrounding organs was then quantitatively evaluated and presented. When kidney function was normal, the dose to the target organ(kidney) was approximately 0.433 mGy/mCi, and the dose to the surrounding organs was approximately 0.138-0.266 mGy/mCi. When kidney function was abnormal, the dose to the surrounding organs was 0.228-0.419 mGy/mCi. This study achieved detailed radiation dose measurements in highly sensitive pediatric patients and enabled the prediction of radiation doses according to kidney function values. The proposed method can provide useful insights for medical radiation exposure management, which is particularly important and necessary for pediatric patients.

Development and validation of an analytical method to quantify baphicacanthin A by LC-MS/MS and its application to pharmacokinetic studies in mice

  • Jeon, So Yeon;Kim, San;Park, Jin-Hyang;Song, Im-Sook;Han, Young Taek;Choi, Min-Koo
    • Analytical Science and Technology
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    • v.35 no.2
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    • pp.60-68
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    • 2022
  • In this study, we developed and validated a sensitive analytical method to quantify baphicacanthin A in mouse plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The standard calibration curves for baphicacanthin A ranged from 0.5 to 200 ng/mL and were linear, with an r2 of 0.985. The inter- and intra-day accuracy and precision and the stability fell within the acceptance criteria. Besides, we investigated the pharmacokinetics of baphicacanthin A following its intravenous (5 mg/kg) and oral administration (30 mg/kg). Intravenously injected baphicacanthin A showed biphasic elimination kinetics with high clearance and volume of distribution values. Furthermore, baphicacanthin A showed a rapid absorption but low aqueous solubility (182.51±0.20 mg/mL), resulting in low plasma concentrations and low oral bioavailability (2.49 %). Thus, we successfully documented the pharmacokinetic properties of baphicacanthin A using this newly developed sensitive LC-MS/MS quantification method, which could be used in future lead optimization and biopharmaceutic studies.

Studies on the Nitrogen Metabolism of Soybeans -II. Variation of Free Amino acids during the Growth of Younger Plants (대두(大豆)의 질소대사(窒素代謝)에 관(關)한 연구(硏究) -II. 유(幼) 식물시기(植物時期)에서의 유리(遊離)아미노산(酸)의 소장(消長))

  • Kang, Y.H.
    • Korean Journal of Soil Science and Fertilizer
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    • v.3 no.1
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    • pp.49-54
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    • 1970
  • In an effort of determine the metabolism and bio-synthesis of nitrogen, was studied at variance of souble nitrogens, free amino acids and total alcohol soluble amino acids during the growth of younger soybean plants, and saybean divides into cotyledon and embryonic organ (shoot and root system) in this experiment. 1. In the soluble nitrogen of soybean, ratio of increase and decrease in the amino acids of them was displayed the near phenomena both cotyledon and embryonic organ of soybean. But, in the 17th days after seed germination, that is the developmeatal stage of adult leaf of soybeans, was appear the maximum value. It has been suggested that the stage of first half period of growth as boundary the stage of adult leaf development which indicated clear morphologically, at the younger soybean plants, is the step that nitrogen assimilation. 2. It was investigated the amino acids of seventeen kinds in the seed state, but at the third days after seed germination, was investigated the amino acids of nineteen kinds. Ultimately, it appears the translocation from cotyledon to embryonic organ in the distribution of amino acid, the nineth day which differentiation begining day of embryonic organ, then after, it happen the variation of number of inspected amino acid in the cotyledon and embryonic organ but only the variance changes in the distribution and quantitative aspects. Especially, the most conspicuous fact was indicated the accumulation of Asparagine, that is the phenomena of Asparagine-accumulation was constitute, not with standing no fertilization from outside. It may be concluded from the results of this investigation that the difference of special phenomena of soybean from the embryo of other plans. 3. In the initial stage of differentiation at embryonic organ number of inspected amino acid was very few, and then, it was slightly appeared the increase-phenomena in the number of them. It was that the amino acid inspecting the initial stage was translocated from the cotyledon. It is suggested that the intermediate-metabolism of amino acid was constituted on the basis of above the result. 4. The phenomena of increase and decrease of total alcohol soluble amino acid were essentially identical to the water soluble amino acid of soybean, but it was appeared the severe difference of amounts in both of them.

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Evaluation of the Apron Effectiveness during Handling Radiopharmaceuticals in PET/CT Work Environment (PET/CT 업무 환경에서 선원 취급 시 Apron의 실효성 평가)

  • Cho, Yong-In;Ye, Soo-Young;Kim, Jung-Hoon
    • Journal of radiological science and technology
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    • v.38 no.3
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    • pp.237-244
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    • 2015
  • Health professionals in nuclear medicine were known that they get high radiation exposure. To reduce radiation exposure, using shielding materials is needed. In this study, we analyzed the shielding effect about apron during 18F-FDG treatment by using simulation based on Monte Carlo techniques and actual measurement. As a result, absorbed dose distribution of organ varies with handling position of the source. Dose reduction ratio by lead thickness of apron tended to decease, when handling position of the source come close to organ and away from radiation source for simulation. In the case of actual measurement with the dosimetry device, It showed that mean spatial dose distribution was different due to characteristics of dosimetry device. However, spatial dose rate was exponentially reduced according to distance with increasing lead content.

Uncertainty Analysis of a Pharmacokinetic Modeling for Inhalation Exposure of Benzene from the Use of Groundwater at Dwelling (거주지의 지하수사용에서 유래한 벤젠의 흡입노출에 대한 동적약리학 모델의 불확실성 분석)

  • 김상준;이현호;박지연;이유진;유동한;양지원
    • Journal of Soil and Groundwater Environment
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    • v.9 no.1
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    • pp.28-38
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    • 2004
  • This study presents the result of uncertainty and sensitivity analysis of a pharmacokinetic model which describes the distribution and removal of benzene at each organ when an indivisual inhales indoor contaminated air with benzene originated from groundwater. The pharmacokinetic model simulates the distribution of benzene deposited in organs of human body through inhalation of contaminated indoor air as well as degradation-metabolism in liver. This study focused on the uncertainty problem induced from the use of the single values for blood flow, partition coefficient, degradation constant, volume, etc. of each organ which was due to a lack of knowledge about these parameters or their measurements. To solve this problem, uncertainty analysis on the pharmacokinetic model was conducted simultaneously which would help understanding the risk assessment associated with VOCs.