• Title/Summary/Keyword: MCA

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First Principle Studies on Magnetism and Electronic Structure of Perovskite Structured CoFeX3 (X = O, F, S, Cl) (페로브스카이트 구조를 가지는 CoFeX3(X = O, F, S, Cl) 합금의 자성과 전자구조에 대한 제일원리계산)

  • Jekal, Soyoung;Hong, Soon Cheol
    • Journal of the Korean Magnetics Society
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    • v.26 no.6
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    • pp.179-184
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    • 2016
  • For an industrial spin-transfer torque (STT) MRAM, low switching current and high thermal stability are required, simultaneously. For this point of view, it is essential to find magnetic materials which satisfy high spin polarization and strong perpendicular magnetocrystalline anisotropy (MCA). In this paper, we investigate electronic structures and MCA energies of perovskite $CoFeX_3$ (X = O, F, S, Cl). For X = F and Cl, spin polarization at the Fermi level are 97 % and 96 %, respectively, which are close to a half metal. Furthermore, Co-terminated 5-monolayer (ML) $CoFeX_3$ (X = O, F, S, Cl) films show perpendicular MCA. In particular, the MCA energy of the Co-terminated $CoFeCl_3$ is about 1.0 meV/cell which is three times larger than that of a 5-ML CoFe film. Therefore, we expect to realize a magnetic material with high spin polarization and strong perpendicular MCA energy by utilizing group 6 and 7 elements in the periodic table, and to contribute to commercializing of the STT-MRAM.

Anti-inflammatory action of p-methoxycinnamic acid (p-Methoxycinnamic acid의 소염작용)

  • 신국현;이은방;우원식
    • YAKHAK HOEJI
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    • v.14 no.3_4
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    • pp.45-50
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    • 1970
  • Anti-infalmmatory action of p-methoxycinnamic acid (p-MCA) was investigated. p-MCA showed a significant decrease in carrageenin and acetic acid induced edema of the rat hind paw, and increased capillary permeability by anaphylaxis and chemical mediators of pontamine sky blue in the mouse peritoneal cavity. It, however, showed only weak inhibitory effect on cotton pellet-induced granuloma formation of the rat.

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Postoperative Change in Hypertrophic Rhinitis(Study Using Nasometer, CSL and Acoustic Rhinometer) (비후성 비염환자에서 음성검사 및 음향비강통기도검사를 이용한 수술전후 비교)

  • 유영삼;우훈영;윤자복;최정환;조경래
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.12 no.1
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    • pp.34-38
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    • 2001
  • Background and Objectives : With the development of computerized systems, an objective evaluation methods of nasal speech and nasal geometry have become readily available by means of a simple, noninvasive technique. In this study, we assessed the nasality, nasal formant, nasal volume and nasal area in patients with hypertrophic rhinitis before and after turbinate surgery. Material and Method : With the nasometer, we measured nasalance, which reflects the ratio of acoustic energy output of nasal sounds from the nasal and oral cavities. With CSL 4300B, we measured nasal formants. We used acoustic rhinometer to measure nasal area and nasal volume. Postoperative changes of above factors were compared with preoperative values. Paired t-test and Pearson's correlation were used for statistical analysis. Results : The first nasal formant frequency, nasalance scores of three passages(baby, mamma and rabbit passages), minimal cross sectional area(MCA) of narrow side, nasal volume of narrow side and nasal volume of wide side had increased significantly after turbinate surgery (p <0.05). The MCA and nasal volume of narrow side and MCA of wide side showed significant correlation with nasalance score of rabbit passage and baby passage showed significant correlation with nasal volume of narrow side(p<0.05). Conclusion : There were significant increases in nasalance scores, first nasal formant frequency, MCA and nasal volume after turbinate surgery. Thus, we must consider the possibility of voice changes postoperatively in professional voice users.

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The Clinical Analysis of Bleeding Pattern in Patients with Ruptured Middle Cerebral Artery Aneurysm (중대뇌동맥 동맥류 파열 환자의 출혈 양상에 대한 임상적 분석)

  • Kim, Hun;Shim, Young Bo;Hwang, Hyung-Sik;Choi, Jae Jun;Kim, Sung Min;Park, Yong Kee;Choi, Sun Kil
    • Journal of Korean Neurosurgical Society
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    • v.30 no.6
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    • pp.699-704
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    • 2001
  • Objectives : The rupture of middle cerebral artery(MCA) aneurysm usually cause or is associated with higher incidence of intracerebral hemorrhages(ICH) than any other aneurysmal ruptures. Also, the outcome of patients who had ICH is known to be worse than patients who had subarachnoid hemorrhage(SAH) only. The authors report the bleeding pattern and outcome of ruptured MCA aneurysm patients. Patients and Methods : A total 106 ruptured MCA aneurysm patients who were surgically treated were included and they were divided into 2 groups by the initial brain CT findings according to the presence or absence of ICH over 10cc in amount. The clinical data were analysed retrospectively. Results : The overall mortality was 18.9%. Among 81 patients(76.4%) who had subarachnoid hemorrhage(SAH) only, 68 patients(84%) showed favorable outcome. Twenty five patients(23.6%) had ICH over 10cc in amount with or without SAH, and among them, 11 patients(44%) showed favorable outcome. The ICH was located in temporal lobe(15 patients, 60%), frontal lobe(3, 12%), sylvian fissure(6, 24%) and frontal-temporal lobe(1, 4%). Among 15 patients who had ICH in temporal lobe, only 4 patients(26.6%) showed favorable outcome and all 3 patients who had ICH in frontal lobe showed favorable outcome. Conclusion : ICH was presented in 23.6% of ruptured MCA aneurysm patients and the prognosis of patients with ICH was worse than patients with SAH only. The ICH was located mainly in the temporal lobe and sylvian fissure.

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Production of Monoclonal Antibody to Infectious Laryngo- tracheitis Virus by Cell Fusion (닭 전염성 후두기관염 바이러스에 대한 단크론성 항체생산)

  • Chung Ok Choi;Chung Gil Lee;Sung Man Cho;Soo Hwan An;Joon Hun Kwon
    • Korean Journal of Poultry Science
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    • v.15 no.3
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    • pp.199-206
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    • 1988
  • A total of 3 hybridoma clones producing monoclonal antibody (MCA) against infectious laryngotracheitis virus (ILTV) was established by somatic cell hybridization between mouse myeloma cells and spleen, cells from mice immunized with ILTV. The MCAs were screened by the indirect flourescent antibody (IFA) staining and the specific hybridomas were cloned by limiting dilution method. The MCAs produced by the 3 hybriomas were all classified as immunogloblin G and found to be reacting against common antigen(s) of high and low pathogenic ILTV examined. The titer of these antibodies in mouse ascitic fluid was from $10^5$ to $10^6$. Indirect fluorescent antibody test using these antibodies was found to be quite effective for the detection of ILTV from infected chickens being the most sensitive among the test methods adopted.

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Changes of Cerebral Metabolism and the Related Factors during Cardiac Surgery

  • Park, Seok-Cheol
    • Biomedical Science Letters
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    • v.8 no.3
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    • pp.143-154
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    • 2002
  • The effect of cardiopulmonary bypass (CPB) on cerebral physiology during heart surgery remains incompletely understood. This study was carried out to investigate changes of cerebral metabolism and the association between the changes and clinical factors during heart surgery. Seventy adult patients (n=70) scheduled for elective cardiac surgery were participated in the present study. Middle cerebral artery blood flow velocity (V$_{MCA}$), cerebral arteriovenous oxygen content difference (C(a-v)O$_2$), cerebral oxygen extraction (COE), and modified cerebral metabolic rate for oxygen (MCMRO$_2$) were measured during six phases of the operation; Pre-CPB, CPB-10 min, Rewarm-1 (nasopharyngeal temperature 34$^{\circ}C$), Rewarm-2 (nasopharyngeal temperature 37$^{\circ}C$), CPB-off, and Post-OP (at skin closure after CPB-off). Each relationship of age, arterial blood gas parameters, or other variables to V$_{MCA}2$, C(a-v)O$_2$, COE, or MCMRO$_2$ was evaluated. V$_{MCA}$ increased (P<0.0001) whereas C(a-v)O$_2$ decreased (P<0.01) throughout the five phases of the operation compared to Pre-CPB value (control). COE diminished at CPB-10, Rewarm-1, and CPB-off (P<0.05) while MCMRO$_2$ reduced at CPB-10 and Rewarm-1 (P<0.05) compared to Pre-CPB value. Positive correlation was found between age and cerebral metabolic parameters (V$_{MCA}$, C(a-v)O$_2$, COE, or MCMRO$_2$) during CPB (range r=0.24 to 0.38, p<0.05). Four cerebral metabolic parameters had partially negative or positive correlation with arterial blood gas parameters and other variables (arterial blood pH, $O_2$ tension, $O_2$ content, $CO_2$ tension, blood pressure, blood flow, temperature, or hematocrit) during the operation. In conclusion, CPB led to marked alterations of cerebral metabolism and age, pH, and $CO_2$ tension profoundly influenced the changes during cardiac surgery.

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Study on the Effect of Gamigehyuldeung-tang on Gultamate Receptor, free Radical and Brain Damage in Rats (가미계혈등탕이 Glutamate receptor와 Free radical 및 뇌손상 보호에 미치는 영향)

  • An Jong suk;Kim Dong Hee;Kim Yun Sik;Lee Young Gu;Park Jong Ho;Namgung Uk;Seol In Chan
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.3
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    • pp.728-737
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    • 2003
  • This study was investigated to prove the effect of GMGHT on the gultamate receptor, free radical and brain damage in rats sujected to Brain Ischemia The results were as follows; 1, GMGHT showed significant inhibitory effect of GMGHT on LDH release induced by NMDA, AMPA, and kinate. 2. GMGHT showed significant inhibitory effect of GMGHT on LDH release induced by BSO and Fe/sup 2+/. 3. GMGHT decreased coma duration time in a infatal dose of KCN and showed 30% of survival rate in a fatal dose. 4. GMGHT decreased ischemic area and edema incited by the MCA blood flow block. 5. GMGHT showed improvement of forelimb and hindlimb test after MCA occulusion in neurological exemination. 6. GMGHT showed no significant change after MCA occulusion in pathological observation as normal group. These results indicate that GMGHT can be used in the brain damage sujected to Brain Ischemia. Further study will be needed about the functional mechanism and etc.

The comparison between normal and cerebral infarction subject;using Transcranial Doppler (경두개 도플러(TCD)를 이용한 정상군과 뇌경색군의 상호비교연구)

  • Choi, Jae-Young;Lee, Dong-Won;Jeong, Sung-Hyun;Lee, Won-Chul
    • The Journal of Internal Korean Medicine
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    • v.19 no.1
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    • pp.157-167
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    • 1998
  • Background and Purpose : Cerebrovascular reactivity(CVR) can be estimated by measuring the change of cerebral blood flow that occurs during vasostimulation. To estimate the cerebrovascular reactivity, we investigated the change of flow velocity of the middle cerebral artery(MCA) during hyperventilation and hypoventilation with the transcranial doppler. So we studied whether the CVR measured by this method could show a significant difference between the normal and the cerebral infarction subjects and whether the CVR may decrease with age in normal subjects. Methods : Using transcranial doppler, we measured the mean velocity(Vm), the pulsatility index(P.I.) at the resting state, the end of breath-holding and the end of hyperventilation in 36 normal and 10 cerebral infarction subjects, so we calculated the percentile change of mean velocity(%${\Delta}$Vm) and P.I.(%${\Delta}$P.I.) after the vasostimulation. We estimated the change of Vm, P.I., %${\Delta}$Vm and %${\Delta}$P.I. by the age group and compared those parameters between the age-matched normal control and cerebral infarction subjects. Results : The Vm in MCA significantly decreased with age(p<0.05), but there was no significant difference in Vm and P.I. between normal and cerebral infarction subjects. The %${\Delta}$Vm and %${\Delta}$P.I. in response to hyperventilation significantly decreased with age in MCA and there was significant difference in $%{\Delta}Vm$ of MCA after breath-holding between the normal and cerebral infarction subjects. Conclusion : The breath-holding and hyperventilation tests could be non-invasive and useful methods in estimation of the cerebrovascular reactivity and could be applied in the basal and follow-up evaluation of the cerebrovascular reserve of the ischemic stroke patients.

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Evaluation of BTA1 and BTA5 QTL Regions for Growth and Carcass Traits in American and Korean Cattle

  • Kim, K.S.;Kim, S.W.;Raney, N.E.;Ernst, C.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.11
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    • pp.1521-1528
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    • 2012
  • Previously identified QTL regions on BTA1 and BTA5 were investigated to validate the QTL regions and to identify candidate genes for growth and carcass traits in commercial cattle populations from the USA and Korea. Initially, a total of 8 polymorphic microsatellite (MS) markers in the BTA1 and 5 QTL regions were used for Chi-square tests to compare the frequencies of individual alleles between high and low phenotypic groups for the US (Michigan Cattleman's Association/Michigan State University; MCA/MSU) cattle. For a subsequent study, 24 candidate genes containing missense mutations and located within the QTL regions based on bovine genome sequence data were analyzed for genotyping in the two commercial cattle populations. Re-sequencing analyses confirmed 18 public missense SNPs and identified 9 new SNPs. Seventeen of these SNPs were used for genotyping of the MCA/MSU cattle (n = 98) and Korean native cattle (n = 323). On BTA1, UPK1B, HRG, and MAGEF1 polymorphisms residing between BM1312 and BMS4048 were significantly associated with growth and carcass traits in one or both of the MCA/MSU and Korean populations. On BTA5, ABCD2, IL22 and SNRPF polymorphisms residing between BL4 and BR2936 were associated with marbling and backfat traits in one or both of the MCA/MSU and Korean cattle populations. These results suggested that BTA 1 and 5 QTL regions may be segregating in both Korean Hanwoo and USA commercial cattle populations and DNA markers tested in this study may contribute to the identification of positional candidate genes for marker-assisted selection programs.

Influences of an Experimental Exposure to Excavator Noise on the Cardiac Factors and Cerebral Hemodynamics

  • Hyun Kyung-Yae;Choi Seok-Cheol;Oh Kwang-Seok;Kwon Heun-Young;Kim Jai-Young;Kim Tae-Un
    • Biomedical Science Letters
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    • v.11 no.3
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    • pp.397-405
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    • 2005
  • Noise may cause damage of the auditory system, hypertension, and cardiovascular disease. However, we haven't the data enough to be available for understanding various effects of noise on the human body. The current study was prospectively designed to investigate the changes of the cardiac factors and cerebral hemodynamics following a transient exposure to noise in young people. 80 subjects (mean aged $23.45\pm2.40$ years) participated in this experiment and were exposed to excavator-noise with 90 decibels for 15 minutes using ear-phone. Cardiac factors such as heart rate (HR), blood pressure (BP) and heart rate-systolic pressure product (RPP), and cerebral hemodynamics such as mean blood flow velocities (Vm), pulsatility indexes (PI), resistance indexes (RI) and mean blood flow velocities at breathing-hold (Vh) in the middle (MCA), anterior (ACA) and posterior cerebral arteries (PCA) were measured before (baseline) and during the noise-exposure. Although there were individual differences in above mentioned parameters, HR, systolic and diastolic BP, RPP, MCA-Vm, MCA-PI, MCA-RI, ACA-Vm, ACA-PI, ACA-RI, PCA-Vm, PCA-PI, and PCA-RI during the noise-exposure decreased compared with the baselines (P<0.05 or P<0.01), The findings of the present study suggest that a transient exposure to excavator-noise at rest causes changes in the cardiac factors and cerebral hemodynamics with individual differences. Further studies need to be carried out for clarifying the effects of longer exposure and combined mental activity with noise exposure.

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