• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권11호
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• pp.2924-2944
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• 2023

Alzheimer's disease (AD) is a neurological condition that is recognized as one of the primary causes of memory loss. AD currently has no cure. Therefore, the need to develop an efficient model with high precision for timely detection of the disease is very essential. When AD is detected early, treatment would be most likely successful. The most often utilized indicators for AD identification are the Mini-mental state examination (MMSE), and the clinical dementia. However, the use of these indicators as ground truth marking could be imprecise for AD detection. Researchers have proposed several computer-aided frameworks and lately, the supervised model is mostly used. In this study, we propose a novel 3D Convolutional Neural Network Multilayer Perceptron (3D CNN-MLP) based model for AD classification. The model uses Attention Mechanism to automatically extract relevant features from Magnetic Resonance Images (MRI) to generate probability maps which serves as input for the MLP classifier. Three MRI scan categories were considered, thus AD dementia patients, Mild Cognitive Impairment patients (MCI), and Normal Control (NC) or healthy patients. The performance of the model is assessed by comparing basic CNN, VGG16, DenseNet models, and other state of the art works. The models were adjusted to fit the 3D images before the comparison was done. Our model exhibited excellent classification performance, with an accuracy of 91.27% for AD and NC, 80.85% for MCI and NC, and 87.34% for AD and MCI.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.116-116
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• 2017

Low-temperature is one of the environmental stress factors that affect plant growth and development and consequently limit crop productivity. The control of seed germination under low-temperature is organized by many genes which are called quantitative trait loci (QTLs). High germination rate for low-temperature is an important factor of growing rice. Previously, we identified a major QTL controlling low-temperature germinability in rice using 96 introgression lines (ILs) derived from a cross between Oryza rufipogon (Rufi) and the Korean japonica cultivar, 'Hwaseongbyeo (HS)'. A $BC_3F_7$ line (TR5) showed better low-temperature germinability than its recurrent parent. TR5 was crossed with HS to develop a segregating F2:3 populations for the target QTL. Six SSR markers polymorphic between HS and Rufi were used to screen and fine map the qLTG1. The qLTG1 on chromosome 1, which accounted for 55.5% of the total phenotypic variation, confirmed that Rufi allele enhanced the low-temperature germinability. Intervals between markers CRM16 and CRM15, four candidate genes were identified. The identified candidate genes, which are encoded by a protein of unknown function, showed their direct involvement on seed germination at low-temperature. To identify genes targeted by qLTG1, we investigated the expression profiles of these candidate genes and germination behavior of qLTG1 under different stress conditions and compared to HS, Rufi, and TR5 at $13{\pm}2^{\circ}C$ for 3 days after incubation. Furthermore, transgenic rice plants will also be developed to conduct a detailed investigation on low-temperature germinability. Hence, the QTL for low-temperature germinability would be useful in rice breeding programs especially in the development of lines possessing low-temperature germinability.

• Investigative Magnetic Resonance Imaging
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• 제22권2호
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• pp.79-85
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• 2018

Purpose: To determine the impact of pseudoglandular formation on apparent diffusion coefficient (ADC) values of hepatocellular carcinoma (HCC) in diffusion-weighted imaging (DWI), and to validate the results using histopathological grades. Materials and Methods: We assessed 182 HCCs surgically resected from 169 consecutive patients. Each type of tumor pseudoglandular formation was categorized into "non-," "mixed-," or "pure-," based on official histopathology reports. The ADC for each tumor was independently measured, using the largest region of interest on the ADC map. Data were assessed using the analysis of variance test, with Bonferroni correction for post hoc analysis to stratify the relationship of ADCs with pseudoglandular formation, followed by subgroup analysis according to the histopathological tumor grades. Results: The mean ADC was significantly higher in pure pseudoglandular lesions (n = 5, $1.29{\pm}0.08{\times}10^{-3}mm^2/s$) than in non-pseudoglandular lesions (n = 132, $1.08{\pm}0.17{\times}10^{-3}mm^2/s$; P = 0.003) or mixed-pseudoglandular lesions (n = 45, $1.16{\pm}0.24{\times}10^{-3}mm^2/s$; P = 0.034). The ADC values and pseudoglandular formation were significantly correlated in moderately differentiated HCCs (n = 103; r = 0.307, P = 0.007), while well- (n = 19) and poorly-differentiated HCCs (n = 60) did not show significant correlation (r = 0.105 and 0.068, respectively; P = 0.600 and 0.685, respectively). Conclusion: The degree of pseudoglandular formation could be one of the determinants of ADC in DWI of HCCs-especially moderately differentiated HCCs-while its influence does not appear to be significant in well- or poorly differentiated HCCs.

• 한국치위생학회지
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• 제16권2호
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• pp.241-248
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• 2016

Objectives: The purpose of the study is to evaluate the dental website usability in Korea. The dental website included dental university hospital, network dental hospital and dental office. Methods: The study was carried out by three age groups including twenties, thirties, and forties. Each group consisted of ten customers and evaluated twelve websites of dental hospitals. Each was assigned to four hospitals and three tasks including easiness of online reservation, preventive information, and treatment information. They filled out the self-administered questionnaire. The questionnaire included the easiness of on-line reservation, satisfaction on the quality and quantity of preventive informations, satisfaction on the quality and quantity of treatment informations, predictiveness on the sub-menu, usefulness of site map, information on the main page of web site, usefulness of decision on visit to dentistry, and revisit intention. Results: The easiness of on-line reservation was the highest in the private dental office, and university dental hospital and network dental hospitals followed in conducting task(1). The anticipated value and measurement on the usefulness of web site were the lowest in network dental hospitals and the time interval between two values was 57 seconds. This discrepancy showed the largest difference. The satisfaction on treatment information in task(3) was higher than that of the satisfaction on preventive information in task (2). The revisit intention was the highest in dental university hospitals. Conclusions: This study showed the comparison in usefulness of web site of university dental hospitals, network dental hospitals and private dental office. The web site focused on the treatment information rather than preventive information. This study suggested that the most important function of dental web site would be the preventive information that was mainly operated by the role of dental hygienists rather than treatment information in the future.

• 대한원격탐사학회지
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• 제34권2_1호
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• pp.267-282
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• 2018

인공위성 영상을 활용한 식생 계절 추정 연구의 지속적 발전에도 불구하고 현장 자료와의 비교를 통한 검증은 다소 미흡한 실정이다. 특히, 다양한 형태로 패치화 되어 있는 우리나라 산림의 경우, 인공위성 영상과 해상도가 일치하지 않는 한계가 존재하여 위성 영상만으로 개엽일을 추정하는데 어려움이 따른다. 본 연구는 식생 계절 추정의 신뢰도를 향상시키기 위해 대축적 임상도(1:5,000)를 MODIS 픽셀 해상도에 맞게 재구성하여 MODIS의 NDVI와 EVI 두 식생지수들로부터 시계열 식물계절 곡선을 생산하여 현장 자료를 바탕으로 우리나라의 산림에 적합한 식생 지수와 개엽일 추출 방법을 비교 및 평가하였다. 또한 각 픽셀의 임상 구성비율과 식생지수로부터의 식물계절 추출 간의 상관관계를 분석하였다. 국립수목원에서 실측된 개엽일을 바탕으로 NDVI와 EVI를 비교하였을 때 우리나라의 산림에는 EVI가 더 적합하였고, 식생지수 계절 곡선으로는 일차도함수가 개엽일 추출에 가장 적합하였다. 현장 개엽일이 조사된 7개의 활엽수종이 속한 픽셀과(중앙픽셀) 이웃한 8개의 픽셀을 실측 개엽일과 비교하였을 때, 실측과 가장 높은 상관관계를 보이는 베스트 픽셀을 구성하는 임상은 활엽수림 67.9%, 침엽수림 14.3%, 혼효림 7.7% 구성을 보였고 평균 결정계수($R^2$)는 0.64으로 나타나 높은 상관관계를 보였다. MODIS EVI로 추출한 전국 평균 개엽일은 최소 112.9일(2014년)에서 최대 129.1일(2010년)으로 2003년 이래로 약 0.16일 빨라졌다. 향후 연구에서는 활엽수림과 혼효림의 개엽일 분석 외에도 다양한 기후 및 지형 인자들의 영향을 파악하기 위해 침엽수림의 개엽일 추출까지 확장할 필요가 있으며 우리나라 산림 생태계의 다양성을 고려한 종합적인 연구가 진행되어야 할 것이다.

• 대한원격탐사학회지
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• 제36권5_2호
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• pp.975-988
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• 2020

변화탐지는 서로 다른 시점에 촬영된 영상에서 일어난 변화를 관측하는 기술로 위성영상을 활용한 원격탐사 분야에서 중요한 기술이다. 변화탐지 기법 중 하나인 무감독 변화탐지 기법은 단시간 내에 변화지역을 추출할 수 있는 장점을 지니지만, 임계값을 통해 변화된 지역을 이진영상으로 나타내기 때문에 토지피복변화를 파악하기 어렵다는 단점이 있다. 본 연구는 이러한 무감독 변화탐지의 단점을 보완하기 위해 공간정보를 기반으로 생성된 격자 포인트를 이용하여 위성영상의 토지피복변화 및 정확도 평가를 수행하였다. 변화탐지 알고리즘은 Spectral Angle Mapper(SAM)를 사용하였으며, 김제자유무역지역 일대를 촬영한 KOMPSAT-3A(K3A) 위성영상을 대상으로 진행하였다. 변화탐지결과는 자동 임계값 추출 알고리즘들 중 Otsu, Kittler, Kapur, Tsai 방법을 사용하여 이진영상으로 나타냈다. 또한, 변화탐지에 사용된 두 시점의 위성영상은 계절에 의한 식생 변화가 존재하기 때문에 확률밀도함수를 통한 Differenced Normalized Difference Vegetation Index(dNDVI)의 임계값으로 계절적 영향을 받는 지역을 제거하였다. 연구 결과, 자동 임계값 추출 알고리즘 중 Otsu와 Kapur의 정확도가 58.16%로 나타났고, dNDVI를 통해 계절적 영향을 제거하였을 때 85.47%로 정확도가 개선된 결과를 보였다. 본 연구결과를 기반으로 생성된 알고리즘은 무감독 변화탐지를 수행할 때 정확도 평가와 토지피복변화를 정량적으로 파악하여 기존의 단점을 보완할 수 있다고 판단된다.

• 한국버섯학회지
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• 제16권1호
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• pp.22-30
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• 2018

본 연구는 표고균사체 발효 적하수오 열수 최적 추출조건 탐색을 목적으로 수행하였으며, 표고균사로 배양된 하수오의 독립변수로는 독립변수(Xi)로서 추출온도(X1), 추출시간(X2) 및 시료에 대한 용매비(X3)에 대한 실험범위를 설정하여 각각을 5단계로 부호화하였고 중심합성계획에 따라 16구로 설정하여 추출하였다. 또한 이들 독립변수에 영향을 받을 종속변수(Yn)로는 고형분 함량(Y1) 및 당도(Y2), TPC (total polyphenol contents, Y3), TFC (total flavonoid contents, Y4), ABTS cation radical scavenging activity (Y5), DPPH radical scavenging activity (Y6)으로 하였다. 고용분 함량 최대값과 최소값은 각각 31.99%와 16.84%로 나타났다. 이를 회귀분석한 결과 고형분 함량에 대한 모델식의 $R^2$은 0.867로 나타났다. 당도는 7번(8 hrs, $85^{\circ}C$, 67 mg/mL)과 15번(6 hrs, $70^{\circ}C$, 100 mg/mL)시험구에서 3.0 brix로 다른 시험구에 비하여 높은 함량을 보였다. 항산화물질인 총 폴리페놀과 플라보노이드 함량은 8번 시험구(8 hrs, $85^{\circ}C$, 40 mg/mL)에서 총 폴리페놀 함량이 30.40 mg GAE/g, 총 플라보노이드 함량이 146.50 mg QE/g으로 가장 높게 나타났으며, 16가지 시험구의 항산화 활성도 총 폴리페놀과 총 플라보노이드 함량의 결과와 같이 8번 시험구(8 hrs, $85^{\circ}C$, 40 mg/mL)에서 가장 높은 활성을 보였다. 이상의 결과를 참조하여 표고균 사체 발효 적하수오에 대한 열수 추출조건을 최적화할 목적으로 추출온도를 $95^{\circ}C$로 고정하고 용매비와 추출시간에 대한 종속변수들의 contour map을 superimposing하여 추출물의 특성 중 생리활성물질 함량과 생리활성을 만족시켜주는 최적조건은 $91.22^{\circ}C$에서 39.71 mg/mL 용매비와 7.72 추출시간으로 각각 분석되었다. 본 연구는 적하수오에 표고균사체를 배양한 후 생리활성이 우수한 원료를 추출 생산하고자 최적 추출조건을 확립하기 위하여 반응표면분석법을 활용하였다. 향후 생리활성부분에 대한 추가적인 연구가 이루어진다면 더욱 완성도가 높은 표고균사체 발효 적하수오 식품개발에 가능할 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권1호
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• pp.43-50
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• 2016

Quantitative trait locus (QTL) is a particular region of the genome containing one or more genes associated with economically important quantitative traits. This study was conducted to identify QTL regions for body weight and growth traits in purebred Korean native chicken (KNC). F1 samples (n = 595) were genotyped using 127 microsatellite markers and 8 single nucleotide polymorphisms that covered 2,616.1 centi Morgan (cM) of map length for 26 autosomal linkage groups. Body weight traits were measured every 2 weeks from hatch to 20 weeks of age. Weight of half carcass was also collected together with growth rate. A multipoint variance component linkage approach was used to identify QTLs for the body weight traits. Two significant QTLs for growth were identified on chicken chromosome 3 (GGA3) for growth 16 to18 weeks (logarithm of the odds [LOD] = 3.24, Nominal p value = 0.0001) and GGA4 for growth 6 to 8 weeks (LOD = 2.88, Nominal p value = 0.0003). Additionally, one significant QTL and three suggestive QTLs were detected for body weight traits in KNC; significant QTL for body weight at 4 weeks (LOD = 2.52, nominal p value = 0.0007) and suggestive QTL for 8 weeks (LOD = 1.96, Nominal p value = 0.0027) were detected on GGA4; QTLs were also detected for two different body weight traits: body weight at 16 weeks on GGA3 and body weight at 18 weeks on GGA19. Additionally, two suggestive QTLs for carcass weight were detected at 0 and 70 cM on GGA19. In conclusion, the current study identified several significant and suggestive QTLs that affect growth related traits in a unique resource pedigree in purebred KNC. This information will contribute to improving the body weight traits in native chicken breeds, especially for the Asian native chicken breeds.

• 천문학회보
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• 제40권1호
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• pp.67.4-68
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• 2015

We present a multi-wavelength observational study of a low-mass star-forming region, L1251-C, with observational results at wavelengths from the near-infrared to the millimeter. Spitzer Space Telescope observations confirmed that IRAS 22343+7501 is a small group of protostellar objects. The extended emission to east-west direction with its intensity peak at the center of L1251A has been detected at 350 and 850 mm with the CSO and JCMT telescopes, tracing dense envelope materials around L1251A. The single-dish data from the KVN and TRAO telescopes show inconsistencies between the intensity peaks of several molecular line emission and that of the continuum emission, suggesting complex distributions of molecular abundances around L1251A. The SMA interferometer data, however, show intensity peaks of CO 2-1 and $^{13}CO$ 2-1 located at the position of IRS 1, which is both the brightest source in IRAC image and the weakest source in the 1.3 mm dust continuum map. IRS 1 is the strongest candidate for being the driving source of a newly detected the compact CO 2-1 outflow. Over the whole region ($14^{\prime}{\times}14^{\prime}$) of L125l-C, 3 Class I and 16 Class II sources have been detected, including three YSOs in L1251A. A comparison with the average projected distance among 19 YSOs in L1251-C and that among 3 YSOs in L1251A suggests L1251-C is an example of low-mass cluster formation, where protostellar objects are forming in a small group.

• Molecules and Cells
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• 제23권1호
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• pp.72-79
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• 2007

Demand for low-input sustainable crop cultivation is increasing to meet the need for environment-friendly agriculture. Consequently, developing genotypes with high nutrient use efficiency is one of the major objectives of crop breeding programs. This study was conducted to identify QTLs for traits associated with physiological nitrogen use efficiency (PNUE). A recombinant inbred population (DT-RILs) between Dasanbyeo (a tongil type rice, derived from an indica ${\times}$ japonica cross and similar to indica in its genetic make-up) and TR22183 (a Chinese japonica variety) consisting of 166 $F_8$ lines was developed and used for mapping. A frame map of 1,409 cM containing 113 SSR and 103 STS markers with an average interval of 6.5 cM between adjacent marker loci was constructed using the DT-RILs. The RILs were cultivated in ordinary-N ($N-P_2O_5-K_2O=100-80-80kg/ha$) and low-N ($N-P_2O_5-K_2O=50-80-80kg/ha$) (100 kg/ha) conditions. PNUE was positively correlated with the harvest index and grain yield in both conditions. Twenty single QTLs (S-QTLs) and 58 pairs of epistatic loci (E-QTLs) were identified for the nitrogen concentration of grain, nitrogen concentration of straw, nitrogen content of shoot, harvest index, grain yield, straw yield and PNUE in both conditions. The phenotypic variance explained by these S-QTLs and E-QTLs ranged from 11.1 to 44.3% and from 16.0% to 63.6%, respectively. The total phenotypic variance explained by all the QTLs for each trait ranged from 35.8% to 71.3%, showing that the expression of PNUE and related characters depends signify- cantly upon genetic factors. Both S-QTLs and E-QTLs may be useful for marker-assisted selection (MAS) to develop higher PNUE genotypes.