• Radiation Oncology Journal
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• v.22 no.2
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• pp.77-90
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• 2004

Purpose: The purpose of this review Is to provide an update on novel radiation treatments for head and neck cancer Recent Findings: Despite the remarkable advances In chemotherapy and radiotherapy techniques, the management of advanced head and neck cancer remains challenging. Epidermal growth factor receptor (EGFR) Is an appealing target for novel therapies In head and neck cancer because not only EGFR activation stimulates many important signaling pathways associated with cancer development and progression, and importantly, resistance to radiation. Furthermore, EGFR overexpression Is known to be portended for a worse outcome in patients with advanced head and neck cancer. Two categories of compounds designed to abrogate EGFR signaling, such as monoclonal antibodies (Cetuxlmab) and tyrosine kinase inhibitors (ZD1839 and 051-774) have been assessed and have been most extensively studied In preclinical models and clinical trials. Additional TKIs In clinical trials include a reversible agent, Cl-1033, which blocks activation of all erbB receptors. Encouraging preclinical data for head and neck cancers resulted In rapid translation Into the clinic. Results from Initial clinical trials show rather surprisingly that only minority of patients benefited from EGFR inhibition as monotherapy or In combination with chemotherapy. In this review, we begin with a brief summary of erbB- mediated signal transduction. Subsequently, we present data on prognostic-predictive value of erbB receptor expression in HNC followed by preclinlcal and clinical data on the role of EGFR antagonists alone or in combination with radiation In the treatment of HNC. Finally, we discuss the emerging thoughts on resistance to EGFR biockade and efforts In the development of multiple-targeted therapy for combination with chemotherapy or radiation. Current challenges for investigators are to determine (1 ) who will benefit from targeted agents and which agents are most appropriate to combine with radiation and/or chemotherapy, (2) how to sequence these agents with radiation and/or cytotoxlc compounds, (3) reliable markers for patient selection and verification of effective blockade of signaling in vivo, and (4) mechanisms behind intrinsic or acquired resistance to targeted agents to facilitate rational development of multi-targeted therapy, Other molecuiar-targeted approaches In head and neck cancer were briefly described, Including angloenesis Inhibitors, farnesyl transferase inhibitors, cell cycle regulators, and gene therapy Summary: Novel targeted theraples are highly appealing in advanced head and neck cancer, and the most premising strategy to use them Is a matter of intense Investigation.

• Journal of Intelligence and Information Systems
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• v.24 no.4
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• pp.111-136
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• 2018

In this paper, we propose a methodology to extract answer information about queries from various types of unstructured documents collected from multi-sources existing on web in order to expand knowledge base. The proposed methodology is divided into the following steps. 1) Collect relevant documents from Wikipedia, Naver encyclopedia, and Naver news sources for "subject-predicate" separated queries and classify the proper documents. 2) Determine whether the sentence is suitable for extracting information and derive the confidence. 3) Based on the predicate feature, extract the information in the proper sentence and derive the overall confidence of the information extraction result. In order to evaluate the performance of the information extraction system, we selected 400 queries from the artificial intelligence speaker of SK-Telecom. Compared with the baseline model, it is confirmed that it shows higher performance index than the existing model. The contribution of this study is that we develop a sequence tagging model based on bi-directional LSTM-CRF using the predicate feature of the query, with this we developed a robust model that can maintain high recall performance even in various types of unstructured documents collected from multiple sources. The problem of information extraction for knowledge base extension should take into account heterogeneous characteristics of source-specific document types. The proposed methodology proved to extract information effectively from various types of unstructured documents compared to the baseline model. There is a limitation in previous research that the performance is poor when extracting information about the document type that is different from the training data. In addition, this study can prevent unnecessary information extraction attempts from the documents that do not include the answer information through the process for predicting the suitability of information extraction of documents and sentences before the information extraction step. It is meaningful that we provided a method that precision performance can be maintained even in actual web environment. The information extraction problem for the knowledge base expansion has the characteristic that it can not guarantee whether the document includes the correct answer because it is aimed at the unstructured document existing in the real web. When the question answering is performed on a real web, previous machine reading comprehension studies has a limitation that it shows a low level of precision because it frequently attempts to extract an answer even in a document in which there is no correct answer. The policy that predicts the suitability of document and sentence information extraction is meaningful in that it contributes to maintaining the performance of information extraction even in real web environment. The limitations of this study and future research directions are as follows. First, it is a problem related to data preprocessing. In this study, the unit of knowledge extraction is classified through the morphological analysis based on the open source Konlpy python package, and the information extraction result can be improperly performed because morphological analysis is not performed properly. To enhance the performance of information extraction results, it is necessary to develop an advanced morpheme analyzer. Second, it is a problem of entity ambiguity. The information extraction system of this study can not distinguish the same name that has different intention. If several people with the same name appear in the news, the system may not extract information about the intended query. In future research, it is necessary to take measures to identify the person with the same name. Third, it is a problem of evaluation query data. In this study, we selected 400 of user queries collected from SK Telecom 's interactive artificial intelligent speaker to evaluate the performance of the information extraction system. n this study, we developed evaluation data set using 800 documents (400 questions * 7 articles per question (1 Wikipedia, 3 Naver encyclopedia, 3 Naver news) by judging whether a correct answer is included or not. To ensure the external validity of the study, it is desirable to use more queries to determine the performance of the system. This is a costly activity that must be done manually. Future research needs to evaluate the system for more queries. It is also necessary to develop a Korean benchmark data set of information extraction system for queries from multi-source web documents to build an environment that can evaluate the results more objectively.

• Investigative Magnetic Resonance Imaging
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• v.8 no.2
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• pp.100-108
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• 2004

Purpose : Early degeneration of articular cartilage is accompanied by a loss of glycosaminoglycan (GAG) and the consequent change of the integrity. The purpose of this study was to biochemically quantify the loss of GAG, and to evaluate the $Gd(DTPA)^{2-}$-enhanced, and T1, T2, rho relaxation map for detection of the early degeneration of cartilage. Materials and Methods : A cartilage-bone block in size of $8mm\;\times\;10mm$ was acquired from the patella in each of three pigs. Quantitative analysis of GAG of cartilage was performed at spectrophotometry by use of dimethylmethylene blue. Each of cartilage blocks was cultured in one of three different media: two different culture media (0.2 mg/ml trypsin solution, 1mM Gd $(DTPA)^{2-}$ mixed trypsin solution) and the control media (phosphate buffered saline (PBS)). The cartilage blocks were cultured for 5 hrs, during which MR images of the blocks were obtained at one hour interval (0 hr, 1 hr, 2 hr, 3 hr, 4 hr, 5 hr). And then, additional culture was done for 24 hrs and 48 hrs. Both T1-weighted image (TR/TE, 450/22 ms), and mixed-echo sequence (TR/TE, 760/21-168ms; 8 echoes) were obtained at all times using field of view 50 mm, slice thickness 2 mm, and matrix $256\times512$. The MRI data were analyzed with pixel-by-pixel comparisons. The cultured cartilage-bone blocks were microscopically observed using hematoxylin & eosin, toluidine blue, alcian blue, and trichrome stains. Results : At quantitation analysis, GAG concentration in the culture solutions was proportional to the culture durations. The T1-signal of the cartilage-bone block cultured in the $Gd(DTPA)^{2-}$ mixed solution was significantly higher ($42\%$ in average, p<0.05) than that of the cartilage-bone block cultured in the trypsin solution alone. The T1, T2, rho relaxation times of cultured tissue were not significantly correlated with culture duration (p>0.05). However the focal increase in T1 relaxation time at superficial and transitional layers of cartilage was seen in $Gd(DTPA)^{2-}$ mixed culture. Toluidine blue and alcian blue stains revealed multiple defects in whole thickness of the cartilage cultured in trypsin media. Conclusion : The quantitative analysis showed gradual loss of GAG proportional to the culture duration. Microimagings of cartilage with $Gd(DTPA)^{2-}$-enhancement, relaxation maps were available by pixel size of $97.9\times195\;{\mu}m$. Loss of GAG over time better demonstrated with $Gd(DTPA)^{2-}$-enhanced images than with T1, T2, rho relaxation maps. Therefore $Gd(DTPA)^{2-}$-enhanced T1-weighted image is superior for detection of early degeneration of cartilage.

• Economic and Environmental Geology
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• v.48 no.4
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• pp.301-312
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• 2015

A commercial gas field was found in the southwestern continental shelf of the Ulleung Basin, East Sea in the late 1990s. To develop additional gas field, an exploration well was drilled through the coarse infill of submarine canyon near the gas field, but it was uneconomic to develop hydrocarbons. Using newly acquired deep seismic reflection and previous well data, we have identified additional geological structure which has hydrocarbon potentials below submarine canyons in the southwestern margin of the basin. Based on the interpretation of the deep seismic reflection and well data, the sequences of the study area can be classified into the syn-rift megasequence(MS1), post-rift megasequence(MS2), syn-compressional megasequence(MS3), and post-compressional megasequence(MS4) in relation to the tectonic events. MS1, deposited simultaneously with the basin formation before the middle Miocene, is characterized by chaotic seismic facies with low- to moderate-amplitude and low frequency reflections. MS2 comprises laterally continuous, low- to moderate-amplitude reflections, showing progradational stacking patterns due to high rates of sediment supply during basin expansion in the middle Miocene. MS3 is mainly composed of continuous reflections with high amplitude and moderate- to high-frequency which are interpreted as coarse-grained sediments. The coarse-grained sediments of MS3 sequence is widely truncated by several submarine canyons which filled with fine-grained sediment of MS4 to form a stratigraphic trap of hydrocarbon. Therefore, the reservoir and seal of the hydrocarbon trap in the study area are coarse-grained sediment of MS3 and submarine canyon filled with fine-grained sediment of MS4, respectively. A flat-spot seismic anomaly, which may indicate the presence of hydrocarbon, is observed within the stratigraphic trap.

• Biomedical Science Letters
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• v.4 no.1
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• pp.11-25
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• 1998

The HLA genes located in the short arm of chromosome 6 specify heterodimeric glycoproteins involved in the regulation of the immune response. Recently, in the elucidation of HLA polymorphism, serological and cellular typing methods have been replaced by DNA typing using polymerase chain reaction (PCR). The purpose of this study was to establish the HLA DNA typing methods and determine gene frequencies of HLA molecules in Koreans. PCR-SSP (sequence specific primers) and PCR-RFLP (restriction fragment length polymorphism) techniques were used for the analysis of HLA-A, -B, -C, DRBl genes and HLA-DQAl, DQBl, DPBl genes, respectively. The results of B-lymphoblastoid cells used for control experiment were consistent with the previous data identified in the 11th International Histocompatibility Workshop. Seventeen, 23, 16, 8, 16, 13 and 37 types of HLA-A, B, C, DQAl, DQBl, DPBl and DRBl alleles were found, respectively, in a total of unrelated 120 Korean individuals. The most frequent HLA alleles were $A^*$02 (27.0%), B$^*$40 (17.6%), Cw$^*$01 (19.2%), DQAl$^*$0301 (32.1%), DQBl$^*$0303 (12.9%), DPBl$^*$0501 (31.3%) and DRBl$^*$1501 (9.2%) among Koreans. This study shows that DNA typing method using PCR technique is a relatively simple, fast and practical tool for the determination of the HLA-class I and II genes. Moreover, the data of HLA gene frequencies could be useful for the Korean database before clinical applications, including organ and unrelated bone marrow transplantation, anthropological study, disease association and individual identification.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.119-124
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• 1997

Purpose: To assess the utility of magnetic resonance(MR) cerebral blood volume (CBV) map in the evaluation of brain tumors. Materials and Methods: We performed perfusion MR imaing preoperatively in the consecutive IS patients with intracranial masses(3 meningiomas, 2 glioblastoma multiformes, 3 low grade gliomas, 1 lymphoma, 1 germinoma, 1 neurocytoma, 1 metastasis, 2 abscesses, 1 radionecrosis). The average age of the patients was 42 years (22yr -68yr), composed of 10 males and S females. All MR images were obtained at l.ST imager(Signa, CE Medical Systems, Milwaukee, Wisconsin). The regional CBV map was obtained on the theoretical basis of susceptibility difference induced by first pass circulation of contrast media. (contrast media: IScc of gadopentate dimeglumine, about 2ml/sec by hand, starting at 10 second after first baseline scan). For each patient, a total of 480 images (6 slices, 80 images/slice in 160 sec) were obtained by using gradient echo(CE) single shot echo-planar image(EPI) sequence (TR 2000ms, TE SOms, flip angle $90^{\circ}$, FOV $240{\times}240mm,{\;}matrix{\;}128{\times}128$, slice-thick/gap S/2.S). After data collection, the raw data were transferred to CE workstation and rCBV maps were generated from the numerical integration of ${\Delta}R2^{*} on a voxel by voxel basis, with home made software (${\Delta}R2^{*}=-ln (S/SO)/TE). For easy visual interpretation, relative RCB color coding with reference to the normal white matter was applied and color rCBV maps were obtained. The findings of perfusion MR image were retrospectively correlated with Cd-enhanced images with focus on the degree and extent of perfusion and contrast enhancement. Results: Two cases of glioblastoma multiforme with rim enhancement on Cd-enhanced Tl weighted image showed increased perfusion in the peripheral rim and decreased perfusion in the central necrosis portion. The low grade gliomas appeared as a low perfusion area with poorly defined margin. In 2 cases of brain abscess, the degree of perfusion was similar to that of the normal white matter in the peripheral enhancing rim and was low in the central portion. All meningiomas showed diffuse homogeneous increased perfusion of moderate or high degree. One each of lymphoma and germinoma showed homogenously decreased perfusion with well defined margin. The central neurocytoma showed multifocal increased perfusion areas of moderate or high degree. A few nodules of the multiple metastasis showed increased perfusion of moderate degree. One radionecrosis revealed multiple foci of increased perfusion within the area of decreased perfusion. Conclusion: The rCBV map appears to correlate well with the perfusion state of brain tumor, and may be helpful in discrimination between low grade and high grade gliomas. The further study is needed to clarify the role of perfusion MR image in the evaluation of brain tumor.

• Journal of radiological science and technology
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• v.26 no.2
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• pp.57-61
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• 2003

The purpose of this study is to compare both 1.5T and 4.7T in Praietal White matter material Phantom using the same methodology at both field strengths. Data at both field strengths are compared in terms of $T_2$ relaxation times, line widths and SNRs MR imaging and $^1H$ MR spectroscopy were performed on GE 1.5T SIGNA system and Broker Biospec 4.7T/30 MRI/MRS system. After phantom axial scan $^1H$ MRS was obtained from T2 weighted image by 3-dimensional localization technique(PRESS : Point RE solved spectroscopy Sequence) this phantom is composed of an aqueous solution 36.7 mmol/L of NAA, 25.0 mmol/L of Cr, 6.3 mmol/L of choline chloride, 30.0 mmol/L or Glu, and 22.5 mmol/L of MI(adjusted to a pH of 7,15 in a phosphate buffet). Data processed using software developed inhouse. At 1.5T, T2 relaxation times for Cho, Cr, and NAA were $0.41{\pm}0.07,\;0.26{\pm}0.04,\;0.46{\pm}0.07$ while at 4.7T they were $0.17{\pm}0.03,\;0.14{\pm}0.05,\;0.20{\pm}0.03$ respectively. At 1.5T, line widths for water, Cho, Cr and NAA were $2.9{\pm}0.7,\;1.6{\pm}0.7,\;1.7{\pm}0.8,\;2.2{\pm}0.02Hz$ while at 4.7T they were $5.2{\pm}1.1,\;4.6{\pm}1.9,\;4.01{\pm}1.8,\;4.8{\pm}1.9Hz$ respectively. It can be seen that $T_2$ relaxation times were significantly shorter at 4.7 compared to 1.5T and that the line widths were also broader. The average SNRs for NAA for subjects at short and long TEs were $23.5{\pm}11.3$ at TE=20 msec ; $15.4{\pm}7.7$ at TE=272 msec at 1.5T and $40{\pm}8.3$ and $17{\pm}3.5$ respectively at 4.7T higher field strength is superior because of improved sensitivity and chemical shift dispersion. However these improvements are partially offset by increased line widths and decrease $T_2$ relaxation times, which act to reduce both sensitivity and resolution. In our experiments with the equipment available to us, 4.7T proton spectra at short TEs exhibit moderately improved sensitivity compared to 1.5T.

• Korean Journal of Agricultural Science
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• v.29 no.2
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• pp.43-52
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• 2002

This study was performed to provide the basic data for preservation and improvement of genetic resources according to finding genetic construction obtained from analysis of genetic characteristics of $\beta$-casein gene in Korean Native goat and Saanen using the PCR-RFLP. This study confirmed the amplified products of 481bp fragments obtained from the amplification of $\beta$-casein loci by PCR. The $\beta$-casein AB genotype showed 481, 284 and 197bp, and $\beta$-casein BB genotype showed 284 and 197bp fragments in Korean Native goat and Saanen. The frequencies of $\beta$-casein genotype in Korean Native goat were 6.25 and 93.75% for AA and AB and the frequencies of $\beta$-casein genotype in Saanen were 57.14 and 42.86% for AA and AB types. The frequencies of $\beta$-casein A and B alleles were 0.031 and 0.969 in Korean Native goat and the frequencies of $\beta$-casein A and B alleles are 0.286 and 0.714 in Saanen, respectively. The nucleotide sequence of $\beta$-casein gene of Korean Native goat was 97.71% higher homology with 11 nucleotide sequences difference of that of goat reported in GeneBank (M90556). Therefore, this study of molecular genetic characteristics by the analysis of genetic polymorphism and sequencing for $\beta$-casein gene should be used as basic and applying data for preservation and improvement of genetic resources in Korean Native goat breeding.

• Progress in Medical Physics
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• v.19 no.2
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• pp.95-101
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• 2008

In this study, we observed the alteration of choline signal intensity in hippocampus region of the depressive rat model induced by forced swimming test (FST). The purpose of this study was to evaluate the antidepressant efficacy in the depressive animal model using MR spectroscopy. Fourteen experimentally naive male Sprague-Dawley rats weighting $160{\sim}180\;g$ were used as subjects. Drug injection group was exposed to the FST except for control group. The drugs were administered subcutaneously (SC) in a volume equivalent to 2ml/kg. And three injections were administered 23, 5, and 1h before beginning the given test. 1H MR spectra were obtained with use of a point resolved spectroscopy (PRESS) localization sequence performed according to the following parameters: repetition time, 2500 ms; echo time, 144 ms; 512 average; 2048 complex data points; voxel dimensions, $1.5{\times}2.5{\times}2.5\;mm^3$ ; acquisition time, 25min. There were no differences in NAA/Cr and Cho/Cr ratio between the right and the left hippocampus both normal control rats and antidepressant-injected rats. Also, no differences were observed in NAA/Cr and Cho/Cr ratio between the normal control rats and the antidepressant-injected rats both the right and the left hippocampus. In this study, we found the recovery of choline signals in the depressive animal model similar to normal control groups as injecting desipramine-HCl which was antidepressant causing anti-immobility effects. Thus, we demonstrated that MR spectroscopy was able to aid in evaluating the antidepressant effect of desipramine-HCl.

• Journal of Internet Computing and Services
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• v.18 no.1
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• pp.77-88
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• 2017

Recently, with the advent of knowledge based society where information and knowledge make values, patents which are the representative form of intellectual property have become important, and the number of the patents follows growing trends. Thus, it needs to classify the patents depending on the technological topic of the invention appropriately in order to use a vast amount of the patent information effectively. IPC (International Patent Classification) is widely used for this situation. Researches about IPC automatic classification have been studied using data mining and machine learning algorithms to improve current IPC classification task which categorizes patent documents by hand. However, most of the previous researches have focused on applying various existing machine learning methods to the patent documents rather than considering on the characteristics of the data or the structure of patent documents. In this paper, therefore, we propose to use two structural fields, technical field and background, considered as having impacts on the patent classification, where the two field are selected by applying of the characteristics of patent documents and the role of the structural fields. We also construct multi-label classification model to reflect what a patent document could have multiple IPCs. Furthermore, we propose a method to classify patent documents at the IPC subclass level comprised of 630 categories so that we investigate the possibility of applying the IPC multi-label classification model into the real field. The effect of structural fields of patent documents are examined using 564,793 registered patents in Korea, and 87.2% precision is obtained in the case of using title, abstract, claims, technical field and background. From this sequence, we verify that the technical field and background have an important role in improving the precision of IPC multi-label classification in IPC subclass level.