• Current Optics and Photonics
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• 제7권1호
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• pp.73-82
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• 2023

In this study, we demonstrate ultrahigh-resolution spectral-domain optical coherence tomography with a 200-kHz line rate using a superluminescent diode with a -3-dB bandwidth of 100 nm at 849 nm. To increase the line rate, a subset of the total number of camera pixels is used. In addition, a partial-spectrum detection method is used to obtain OCT images within an imaging depth of 2.1 mm while maintaining ultrahigh axial resolution. The partially detected spectrum has a flat-topped intensity profile, and side lobes occur after fast Fourier transformation. Consequently, we propose and apply the super-Gaussian window function as a new window function, to reduce the side lobes and obtain a result that is close to that of the axial-resolution condition with no window function applied. Upon application of the super-Gaussian window function, the result is close to the ultrahigh axial resolution of 4.2 ㎛ in air, corresponding to 3.1 ㎛ in tissue (n = 1.35).

• Anatomy and Cell Biology
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• 제56권2호
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• pp.276-279
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• 2023

The arterial support of the liver is most commonly from the celiac trunk via the proper hepatic artery (PHA). The PHA divides into left and right branches: the right hepatic artery (RHA) supplies the right and caudate lobes while the left hepatic artery (LHA) supplies the left and quadrate lobes. Aberrant hepatic arteries are relatively common, and the most frequent contributors are the superior mesenteric artery and left gastric artery. Herein we present findings from postmortem dissection of an abdominal cavity that revealed a rare combination of reported variations. Specifically, this subject had three extrahepatic arteries - a replaced LHA (rLHA), a PHA, and a replaced RHA (rRHA). The rLHA originated from the left gastric and the rRHA originated from the superior mesenteric artery. Knowledge of these variations is important for surgical and radiological procedures to avoid complications during treatment and improve patient outcomes.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 12th Asian Congress of Fluid Mechanics
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• pp.66.1-66.1
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• 2008

• 한국임상수의학회지
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• 제31권3호
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• pp.233-236
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• 2014

피부염 치료를 위해 스테로이드를 처방받은 경력이 있는 11년령 수컷 시추가 비만, 얇은 피모, 복부 팽만으로 내원하였다. 방사선 사진상 폐야 전반에 기관지-간질패턴과 뚜렷한 흉막음영이 관찰되었으나 신체검사상 이와 관련한 증상은 보이지 않았다. 복부 초음파상 부신은 정상크기이며 간실질의 에코성 상승을 나타내었다. 컴퓨터 단층촬영상 폐 중앙부는 간유리음영을 나타내었으며 변연부는 중앙부에 비해 저감약성을 띄고, 고감약성 결절음영이 폐 실질전반에 산재되어 있었다. 영상진단학적 소견과 부신피질자극 호르몬 검사결과를 바탕으로 의인성 부신피질기능항진증과 속발성 폐 석회화로 진단하였다.

• 생물정신의학
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• 제12권1호
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• pp.68-72
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• 2005

Object:Nicotine dependence is the most common substance abuse disorder. One of the characteristics of nicotine dependence is craving. Regional activation of the brain induced by craving for nicotine was evaluated by using functional magnetic resonance imaging to investigate neuroanatomical site of smoking craving. Method:A smoker who satisfied DSM-IV criteria for nicotine dependence and a non smoker was studied. MRI data were acquired on a 1.5T Magnetom Vision Plus with a head volume coil. Two sets of visual stimuli were presented to subjects in a random manner. One was the film scenes of inducing smoking craving and the other was neutral stimuli not related to smoking. There were two fMRI sessions before and after smoking or sham smoking. Data were analyzed using SPM99. Results:fMRI showed significant activated area in anterior cingulate and medial frontal lobes in the smoker during smoking craving. Right dorsolateral prefrontal cortex and parietal lobes were activated in the control during visual stimulation before smoking. After smoking, there was no brain activation during visual stimulation in both of smoker and non smoker. Conclusion:Metabolic activity of the anterior cingulate and medial frontal lobes increased during craving for smoking. This result suggests that fMRI may be a valuable tool in the identification of neurobiological process of craving.

• Annals of Clinical Neurophysiology
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• 제19권2호
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• pp.101-112
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• 2017

Detection of underling proteinopathies is becoming increasingly important across neurodegenerative conditions due to upcoming disease intervention trials. In this review, we explored how temporal lobe changes in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) can potentially predict underlying TDP-43 pathology subtypes in FTD. To date, emphasis has been given to frontal lobe changes in the study of the cognitive and behavioural impairments in both syndromes but an increasing number of pathological, imaging and neuropsychological studies suggest how temporal lobe changes could critically affect the cognition and behaviour of these conditions. In this current article, we reviewed pathological, imaging as well as clinical/neuropsychological findings of temporal involvement in the ALS-FTD continuum, how they relate to temporal lobe changes and the underlying TDP-43 pathology in FTD. Findings across studies show that TDP-43 pathology occurs and coincides in many structures in ALS and FTD, but especially in the temporal lobes. In particular, anterior and medial temporal lobes atrophy is consistently found in ALS and FTD. In addition, memory and language impairment as well as emotional and Theory of Mind processing deficits that are characteristics of the two diseases are highly correlated to temporal lobe dysfunction. We conclude by showing that temporal lobe changes due to TDP-43 type B might be particular predictive of TDP-43 type B pathology in behavioural variant FTD, which clearly needs to be investigated further in the future.

• 감성과학
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• 제16권4호
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• pp.527-534
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• 2013

본 연구에서는 코히어런스 분석을 통하여 시각집중 기간 동안 시간 변화에 대한 뇌기능과 관련된 공간-주파수간 연관관계를 해석하였다. 집중관련 시각자극 실험 데이터를 통해 ${\theta}$와 ${\alpha}$ 대역에서 서로 다른 두피 위치간 위상연관변화를 확인하였다. 좌우 전두엽, 전두엽과 두정엽 간 뇌유발전위는 P100, N200지점에서 위상동조를 보였으며, 전두엽과 후두엽 간 뇌유발전위는 시각 처리 정보가 반영되는 P300지점에서 위상동조를 보였다. 고정된 길이의 창을 이용하는 단구간 푸리에 변환에 비하여 연속 웨이블릿 변환은 모 웨이블릿의 파라미터 조정을 통한 다중해상도 분석이 가능하였다. 따라서 연속 웨이블릿 변환을 이용한 코히어런스 결과가 시간변화에 대한 뇌유발전위의 공간-주파수간 연관관계의 변화를 확인하는데 유효함을 확인하였다. 비 집중 자극수행에 대해서는 위상동조 현상이 나타나지 않았다.

• Journal of Chest Surgery
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• 제23권4호
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• pp.698-706
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• 1990

Congenital Cystic Lung Disease is a spectrum of closed related anomalies that arise during an early stage of embryonic lung bud maturation-namely bronchogenic cyst, congenital lobar emphysema, pulmonary sequestration and congenital cystic adenomatoid malformation. And they show similar surgical strategies. So they are called as the term bronchopulmonary-foregut malformations, firstly proposed by Gerle[1968]. From Aug. 1979 to Aug 1989, 47 patients were operated upon on Dept. of Thoracic & Cardiovascular Surgery at the CUMC. There were 21 females and 26 males ranging in age from age of 21 day to age of 56 year [15 cases under 15 years old]. 30 patients had bronchogenic cysts - 23 of intrapulmonary type, 7 of mediastinal type in location. Affected lobes and locations were as follows: 11 in upper lobe, 3 in middle lobe, 11 in lower lobe and anterosuperior, middle, and posterior mediastinal type were 3, 2, 2 respectively. There were 9 pulmonary sequestrations[all intralobar type] with the distribution of 5 in right lower lobe and 4 in left lower lobe. And associated anomalies were presented with arterial supply originating from thoracic aorta[8 cases], abdominal aorta[1 case] and with venous drainage into azygos vein[1 case]. They all were operated upon lower lobectomy [8 case], pneumonectomy[1 case] in case of pulmonary hypoplasia Congenital lobar emphysema and congenital cystic adenomatoid malformation had 4 cases respectively. Their affected lobes were as follows: the former were 3 in upper lobes, 1 in middle lobe and the latter were 3 in upper lobe, 1 in lower lobe. They were treated with lobectomy and segmentectomy. Diagnosis was aided by chest X - ray, bronchography, aortography, DSA and CT scan, They all were confirmed by pathologic exams. There were no hospital death but few minor morbidities such as, atelectasis-pneumonia[2], wound infection[2], prolonged chest tube placement[2]. We experienced surgical treatments of 47 cases for 10 years and reported them with literature review.

• 수산해양기술연구
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• 제46권2호
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• pp.173-183
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• 2010

In a split beam echo sounder, the transducer design needs to have minimal side lobes because the angular position and level of the side lobes establishes the usable signal level and phase angle limits for determining target strength. In order to suppress effectively the generation of unwanted side lobes in the directivity pattern of split beam transducer, the spacing and size of the transducer elements need to be controlled less than half of a wavelength. With this purpose, a 50 kHz tonpilz type transducer with a half-wavelength diameter in relation to the development of a split beam transducer was designed using the equivalent circuit model, and the underwater performance characteristics were measured and analyzed. From the in-air and in-water impedance responses, the measured value of the electro-acoustic conversion efficiency for the designed transducer was 51.6%. A maximum transmitting voltage response (TVR) value of 172.25dB re $1{\mu}Pa/V$ at 1m was achieved at 52.92kHz with a specially designed matching network and the quality factor was 10.3 with the transmitting bandwidth of 5.14kHz. A maximum receiving sensitivity (SRT) of -183.57dB re $1V/{\mu}Pa$ was measured at 51.45kHz and the receiving bandwidth at -3dB was 1.71kHz. These results suggest that the designed tonpilz type transducer can be effectively used in the development of a split beam transducer for a 50kHz fish sizing echo sounder.

• 한국산학기술학회논문지
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• 제22권4호
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• pp.430-440
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• 2021

본 연구는 난청 고령자의 우울정도, 인지기능, 의사소통능력 및 정량뇌파를 분석하고, 관련성을 규명할 목적으로 시도하였다. Y 시 소재의 S 청능재활 센터를 내원한 60세 이상의 난청 고령자 중 모집공고문을 통해 남성 37명, 여성 26명이 2020년 6월 20일부터 2020년 9월 3일까지 자발적으로 참여했다. 구조화된 설문지를 통해 대상자의 전반적인 특성, 우울정도, 인지기능을 평가하였다. 의사소통능력의 척도인 단어인지도는 한국표준 단음절어를 사용하여 진단용 청력검사기로 평가하였다. 정량뇌파는 전전두엽 Fp1과 Fp2에 건식 전극을 사용하여 2채널 뇌파 측정기로 측정하였다. 수집된 자료는 SPSS/WIN 25.0 프로그램으로 인구 사회학적 특성 파악을 위한 빈도분석, 변수간 Pearson's correlation분석, 3분할 집단 간 One-way ANOVA분석을 하였다. 결과를 요약하면 다음과 같다. 의사소통능력은 전전두엽 좌우 대칭성(**p<.01)과 정(+)적 상관관계를 보였고, 우뇌 정신적 산만 및 스트레스(*p<.05)와 부(-)적 상관관계를 보였다. 그러나 우울정도와 인지기능과는 유의한 상관관계는 없었다. 의사소통능력에 따른 3분할 집단별 차이 검정에서도 전전두엽 좌우 대칭성(**p<.01)이 우울정도와 인지능력보다 높은 수준의 상관관계를 보였다. 이상의 결과는 정량뇌파에서 측정된 전전두엽 좌우 대칭성이 난청 고령자의 의사소통능력의 강력한 생체적 지표 가능성을 시사 하였다.