• Current Optics and Photonics
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• v.7 no.1
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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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• v.56 no.2
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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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• 2008.08a
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• pp.66.1-66.1
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• 2008

• Journal of Veterinary Clinics
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• v.31 no.3
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• pp.233-236
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• 2014

An 11-year-old, intact male Shih Tzu presented with obesity, thin hair coat, and abdominal distention. The patient had previously received corticosteroid therapy for dermatitis. Thoracic radiographs showed incidental findings of a generally diffuse bronchointerstitial pattern and markedly radiolucent pleural lines between the middle and caudal lung lobes, but clinical signs related to the thoracic radiographic findings were absent. Echogenicity of the hepatic parenchyma was increased and bilateral adrenal glands were not enlarged on ultrasonography. On computed tomography, the central regions of the lung lobes showed ground-glass attenuation, the peripheral regions of the lung lobes were relatively hypoattenuated compared with the central regions, and hyperattenuated nodules were distributed throughout the pulmonary parenchyma. Iatrogenic hyperadrenocorticism and secondary pulmonary mineralization was diagnosed on the basis of diagnostic imaging and adrenocorticotropic hormone stimulation test.

• Korean Journal of Biological Psychiatry
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• v.12 no.1
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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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• v.19 no.2
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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.

• Science of Emotion and Sensibility
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• v.16 no.4
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• pp.527-534
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• 2013

In this study, we analyzed spatial-frequency relationship related brain function for change of the time during attentional visual stimulus through the analysis of Coherence. With experimentation about ERP(Event Related Potential)data, it revealed that change of the phase synchronization between different scalp locations at ${\theta}$, ${\alpha}$ band. ERP between left and right frontal lobes, between the frontal and central lobes showed the phase synchronization at the P100, N200, ERP between the frontal and occipital lobes showed the phase synchronization at the P300 related information of visual stimulus. Compared to STFT using the window of a fixed length, CWT is able to multi-resolution analysis with the adjustment of parameters of mother wavelet. Thus, coherence results with CWT was found to be effective for analysis of time-varying spatial-frequency relationship in ERP. The phase synchronization for inattentional visual stimulus was not observed.

• Journal of Chest Surgery
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• v.23 no.4
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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.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.2
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.430-440
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• 2021

The purpose of this study was to analyze the degree of depression, cognitive function, communication ability, and the quantitative electroencephalogram (EEG) in elderly individuals with hearing loss and to investigate their inter-relationship. Hearing-impaired elderly participants, aged 60 years or older (37 men and 26 women) who visited the S Hearing Rehabilitation Center in Y City from June 20, 2020, to September 3, 2020, participated voluntarily after a recruitment announcement.The participants' overall characteristics, depression, and cognitive functions were evaluated with a structured questionnaire. The Word Recognition Score (WRS) was evaluated with an audiometer using the Korean Standard Monosyllabic Word Lists for Adults (KS-MWL-A). The quantitative EEG was measured with dry electrodes using a 2-channel EEG on the frontal lobes Fp1 and Fp2. The results are summarized as follows: Communication ability showed a positive correlation with the left-right symmetry of the frontal lobes (**p<.01) and a negative correlation with right-brain mental distraction and stress (*p<.05). In the difference WRS test for each group, the left-right symmetry of the frontal lobes (**p<.01) showed the greatest correlation with communication ability. Our results suggest that the left-right symmetry of the frontal lobes can be a biomarker indicative of the communication ability of older people with hearing impairments.