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Feature Weighting for Opinion Classification of Comments on News Articles (뉴스 댓글의 감정 분류를 위한 자질 가중치 설정)

  • Lee, Kong-Joo;Kim, Jae-Hoon;Seo, Hyung-Won;Rhyu, Keel-Soo
    • Journal of Advanced Marine Engineering and Technology
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    • v.34 no.6
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    • pp.871-879
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    • 2010
  • In this paper, we present a system that classifies comments on a news article into a user opinion called a polarity (positive or negative). The system is a kind of document classification system for comments and is based on machine learning techniques like support vector machine. Unlike normal documents, comments have their body that can influence classifying their opinions as polarities. In this paper, we propose a feature weighting scheme using such characteristics of comments and several resources for opinion classification. Through our experiments, the weighting scheme have turned out to be useful for opinion classification in comments on Korean news articles. Also Korean character n-grams (bigram or trigram) have been revealed to be helpful for opinion classification in comments including lots of Internet words or typos. In the future, we will apply this scheme to opinion analysis of comments of product reviews as well as news articles.

Valproic Acid Increases Expression of Neuronal Stem/Progenitor Cell in Spinal Cord Injury

  • Bang, Woo-Seok;Kim, Kyoung-Tae;Cho, Dae-Chul;Kim, Hye-Jeong;Sung, Joo-Kyung
    • Journal of Korean Neurosurgical Society
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    • v.54 no.1
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    • pp.8-13
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    • 2013
  • Objective : This study investigates the effect of valproic acid (VPA) on expression of neural stem/progenitor cells (NSPCs) in a rat spinal cord injury (SCI) model. Methods : Adult male rats (n=24) were randomly and blindly allocated into three groups. Laminectomy at T9 was performed in all three groups. In group 1 (sham), only laminectomy was performed. In group 2 (SCI-VPA), the animals received a dose of 200 mg/kg of VPA. In group 3 (SCI-saline), animals received 1.0 mL of the saline vehicle solution. A modified aneurysm clip with a closing force of 30 grams was applied extradurally around the spinal cord at T9, and then rapidly released with cord compression persisting for 2 minutes. The rats were sacrificed and the spinal cord were collected one week after SCI. Immunohistochemistry (IHC) and western blotting sample were obtained from 5 mm rostral region to the lesion and prepared. We analyzed the nestin immunoreactivity from the white matter of ventral cord and the ependyma of central canal. Nestin and SOX2 were used for markers for NSPCs and analyzed by IHC and western blotting, respectively. Results : Nestin and SOX2 were expressed significantly in the SCI groups but not in the sham group. Comparing SCI groups, nestin and SOX2 expression were much stronger in SCI-VPA group than in SCI-saline group. Conclusion : Nestin and SOX2 as markers for NSPCs showed increased expression in SCI-VPA group in comparison with SCI-saline group. This result suggests VPA increases expression of spinal NSPCs in SCI.

Food behaviors accounting for the recent trends in dietary fatty acid profiles among Korean adults

  • Song, SuJin;Shim, Jae Eun
    • Nutrition Research and Practice
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    • v.16 no.3
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    • pp.405-417
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    • 2022
  • BACKGROUND/OBJECTIVES: This study examined the changes in food behaviors of dietary fatty acids over 2007-2018 among Korean adults. SUBJECTS/METHODS: This study used data from the 4th (2007-2009), 5th (2010-2012), 6th (2013-2015), and 7th (2016-2018) Korea National Health and Nutrition Examination Surveys. A total of 46,307 adults aged 19-64 yrs were selected and dietary data were obtained from a single 24-h recall. In the 4th and 7th data, the major food sources for each fatty acid based on the contributing percentage of the food item were compared. The consumption trends in the major food sources were presented as grams per day over 2007-2018 and compared across the survey periods using the multiple regression model. RESULTS: From 2007 to 2018, for total fat, saturated fatty acid (SFA), and monounsaturated fatty acid, the contribution of animal food sources, including beef, chicken, and eggs increased but plant food sources (e.g., tofu, soybean, and plant oil) decreased. As polyunsaturated fatty acid sources, mayonnaise, eggs, and bread showed higher contributions, whereas soybean and tofu showed lower contributions in the 7th data compared to the 4th data. For n-3 fatty acids, the contribution of fish decreased between the 4th and 7th data. Over 12 yrs, the significant increases in the absolute amount of consumption from animal sources were observed. In contrast, decreases in the consumption from plant sources and fish were seen across the survey periods. CONCLUSIONS: In Korean adults, increases in the intake of dietary fatty acids along with changes in the food behaviors during 2007-2018 have evoked great concern for SFA intake, which is a cardiovascular disease risk factor. Healthy food sources of dietary fatty acids should be emphasized in this population.

THE VERIFICATION OF THE MTT ASSAY ON THE VIABILITY OF PERIODONTAL LIGAMENTAL CELLS IN RAT MOLARS THROUGH THE HISTOLOGIC EXAMINATION (쥐치아 치근면의 치주인대세포의 활성도를 평가하는 방법으로 MTT검색법의 적절성에 대한 조직학적인 검증)

  • Kim, Hyun-Ki;Kim, Eui-Seoung;Choi, In-Bok;Kim, Jin;Lee, Seung-Jong
    • Restorative Dentistry and Endodontics
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    • v.28 no.5
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    • pp.385-391
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    • 2003
  • The purpose of this study is to examine the viability of PDL cells in rat molars by using MTT assay and to verify the MTT assay through the histologic observation. Thirty of Sprague-Dawley white female rats of 4-weeks old with a body weight of about 100 grams were used. Groupings are as follows : Immediate Group : Positive control group(n=10)-after extraction immediately. Dried Group : Negative control group(n=10)-after drying for an hour under warm dry. $ViaSpan^{\circledR}$ Group : 1hour $ViaSpan^{\circledR}$ group(n=10)-after storing in $ViaSpan^{\circledR}{\;}at{\;}4^{\circ}C$ for 1hour. Ten teeth of each group were treated as same as above and replanted to the original socket of experimental animals. After two weeks of replantation. all the experimental animals were sacrificed. And after fixation, extracted maxillary jaw was dimineralized. After it was embedded in paraffin. serial section by $5\mu\textrm{m}$ was carried out and for construction of specimen, hematoxylin-eosin dye was used. The mean MTT measurement of immediate group(positive control) is 2.81 and the mean measurement of dried group(negative control) is 0.98 which is significantt differnt(P<0.05), The mean measurement of $ViaSpan^{\circledR}$ group is 2.65 and there is significant difference between dried group and $ViaSpan^{\circledR}$ group(P<0.05), However, there is no difference between immediate group and $ViaSpan^{\circledR}$ group. The average resorption points of immediate group is 3.03 points. In the dried group, average 6.44 points resorption and 2.68 points showed resorption in the $ViaSpan^{\circledR}$ group. Unlike with MTT assay, there was no significant difference between the immediate group and $ViaSpan^{\circledR}$ group. The usage of MTT assay as a viable cell marker may give us a better indication of the maintenance of periodontal ligament cell vitality.

Alveolar bone turnover during experimental tooth movement in Streptozotocin-induced diabetic rat (스트렙토조토신 유발 당뇨병 백서에서 실험적 치아이동중의 치조골 교체)

  • Lee, Ki-Soo;Lee, Taek-Woo;Kim, Sung-Jin
    • The korean journal of orthodontics
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    • v.31 no.3 s.86
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    • pp.357-367
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    • 2001
  • The purpose of this study was to investigate the alveolar bone turnover in diabetic rat, and to compare the alveolar bone turnover during tooth movement in diabetes with that in normal control Eighty Male Sprague-Dawley strain rats(8th week) were divided into normal control(N), normal-tooth movement (N-tm), diabetes(D), and diabetes-tooth movement(D-tm) groups. Eighteen days before the start of the experiment, diabetes was induced with a single injection of streptozotocin 50 mg/kg of body weight in citrate buffer as vehicle via the tail vein. Maxillary first molars of rats were moved mesially by 40 grams of the closed coil spring. Experimental animals were sacrificed after 1d, 3d, 7d, and 14d experimental period, and the alveolar bone around the maxillary first molars were assayed biochemically for acid phsophatase(ACP) and tartrate-resistant acid phosphatase (TRAP) as bone resorption markers, and alkaline phosphatase(ALP) and osteocalcin(OC) as bone formation markers. TRAP and OC concentration in serum and alveolar bone of D group were lower than those in N group, and especially OC concentration decreased mote following diabetes prolonged, which showed the decreased skeletal and alveolar bone resorption and formation potential in diabetic rats. In N-tm group compared with N group, alveolar bone ACP and TRAP concentrations were highest at 1d and 3d(p<0.01), decreased after then, and showed lowest at 14d, and alveolar bone OC concentration was higher at 3d, 7d, and 14d(p<0.001) and showed a tendency of peak level at 7d. which showed the peak of concentration of bone resorption markets at 1d-3d and those of bone formation markers at 7d. In D-tm group compared with N group, alveolar bone ACP and TRAP concentrations were higher at 3d, 7d and 14d(p<0.001), and tended to reach peak value at 7d and persisted through 14d, and alveolar bone ALP and OC concentration increased but not different from that of N group. The amount of tooth movement in D group were greater than that of N group at all experimental period. Those results were suggested that during diabetes, the alveolar and skeletal bone undergo low bone turnover and the mote amount of tooth movement, hut because the peak time of alveolar bone resorption activity was delayed and sustained in longer period of tooth movement and alveolar bone formation activity is lower than that of normal tooth movement, the periodontal space is supposed to be larger doting tooth movement.

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A Classification Model for Attack Mail Detection based on the Authorship Analysis (작성자 분석 기반의 공격 메일 탐지를 위한 분류 모델)

  • Hong, Sung-Sam;Shin, Gun-Yoon;Han, Myung-Mook
    • Journal of Internet Computing and Services
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    • v.18 no.6
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    • pp.35-46
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    • 2017
  • Recently, attackers using malicious code in cyber security have been increased by attaching malicious code to a mail and inducing the user to execute it. Especially, it is dangerous because it is easy to execute by attaching a document type file. The author analysis is a research area that is being studied in NLP (Neutral Language Process) and text mining, and it studies methods of analyzing authors by analyzing text sentences, texts, and documents in a specific language. In case of attack mail, it is created by the attacker. Therefore, by analyzing the contents of the mail and the attached document file and identifying the corresponding author, it is possible to discover more distinctive features from the normal mail and improve the detection accuracy. In this pager, we proposed IADA2(Intelligent Attack mail Detection based on Authorship Analysis) model for attack mail detection. The feature vector that can classify and detect attack mail from the features used in the existing machine learning based spam detection model and the features used in the author analysis of the document and the IADA2 detection model. We have improved the detection models of attack mails by simply detecting term features and extracted features that reflect the sequence characteristics of words by applying n-grams. Result of experiment show that the proposed method improves performance according to feature combinations, feature selection techniques, and appropriate models.

The use of Intravenous Albumin for the Prevention of Ovarian Hyperstimulation Syndrome in Patients at High Risk in in Vitro Fertilization (과배란유도에 의한 난소과자극증후군 발생 고위험군에 있어서 알부민 정맥투여요법의 효과에 관한 연구)

  • Moon, Shin-Yong;Roh, Jae-Sook;Lee, Kyung-Soon;Suh, Chang-Suk;Kim, Seok-Hyun;Choi, Young-Min;Shin, Chang-Jae;Kim, Jung-Gu;Lee, Jin-Yong;Chang, Yoon-Seok
    • Clinical and Experimental Reproductive Medicine
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    • v.22 no.2
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    • pp.171-181
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    • 1995
  • Ovarian hyperstimulation syndrome(OHSS) is one of the well-known complication of controlled ovarian hyperstimulation(COH). Though there have been numerous measures to prevent the occurrence of OHS, it has not been completely preventable until now. The fluid shift from the intravascular space to the third space is due to decreased oncotic pressure of the serum. The objective of this study was to evaluate if IV administration of 20% albumin in those patients with OHSS risk can make prevention of severe OHSS. We retrospectively analysed 70 patients undergoing IVF-ET who had serum peak estradiol($E_2$) level of >2,500 pg/ml and/or the number of oocytes retrieved over 20. The treatment group(n=39) received albumin while the control group(n=31) did not. After 40 grams of human albumin diluted in 1,000 ml of 0.9% sodium chloride solution, the treatment group received half of the fluid during oocyte retrieval, the remainder in the recovery suite. The results were as follows; There were significant differences in the levels of serum peak $E_2$ and number of oocytes retrieved between the two groups(p<0.05). However, there were no significant differences in the incidence of OHSS and pregnancy rate or multifetal pregnancy rate. In conclusion, administration of albumin to OHSS risk patients did not reduce the rate of OHSS in IVF-ET. However, if we consider the fact that there were differences in the level of peak serum $E_2$ and oocyte numbers, further prospective study may be needed.

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Effect of Temperature on Soil Microbial Biomass, Enzyme Activities, and PLFA content during Incubation Period of Soil Treated with Organic Materials (유기물원 항온배양 온도가 토양미생물체량과 효소활성 및 PLFA함량에 미치는 영향)

  • Joa, Jae-Ho;Moon, Doo-Gyung;Chun, Seung-Joung;Kim, Chun-Hwan;Choi, Kyung-San;Hyun, Hae-Nam;Kang, Ui-Gum
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.6
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    • pp.500-512
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    • 2009
  • This study was carried out to evaluate the effect of temperature on soil microbial biomass, enzyme activities, and PLFA content in the volcanic(VAS) and the non-volcanic ash soil(NVAS). The soils were treated with organic materials such as organic fertilizer pelleted(OFPL), organic fertilizer powdered(OFPD), pig manure compost(PMC), and food waste compost(FWC). Two grams of organic materials were well mixed with 30g of dried volcanic and non-volcanic ash soil(< 2 mm) with 50% of soil moisture content. And the soils were incubated at 10, 20, $30^{\circ}C$ in incubator. Soils were analysed on the incubation times as followed; soil pH, total nitrogen, organic matter(at 75, 150, 270 days), microbial biomass C and PLFA (at 75, 270 days), microbial biomass N and soil enzyme(at 150, 270 days). pH values of soils treated with PMC and FWC had no changes on soil type, and incubation temperature. However, the pH was increased with temperature in the soils treated with OFPL. The changes in NVAS was higher than in VAS. Soil microbial biomass C content were high in the condition of high temperature and organic fertilizers treatment in VAS. But the contents were gradually decreased with incubation period in both NVAS and VAS. Soil microbial biomass N was high in NVAS treated with organic fertilizers and in VBS treated with PMC and FWC. PLFA content was higher in NVBS than in VBS at 75 days but showed high in VBS at 270 days. Urease activity of NVBS treated with OFPL showed $10^{\circ}C$ (75.0)> $20^{\circ}C$ (16.3)>$30^{\circ}C$ ($4.6ug\;NH{_4-}N\;g^{-1}\;2h^{-1}$) at 150 days. It were decreased gradually high temperature and time passes. And it showed high at $10^{\circ}C$ in VBS. Glucosidase activity was higher in NVBS than in VBS. Correlation coefficient of between soil microbial biomass C and microbial activity indicators showed that PLFA was high significantly at $r^2=0.91$ in NVBS and ${\beta}-glucosidase$ was $r^2=0.83$ in VBS. Soil microbial activities showed differences in the relative sensitivities of soil type and soil temperature.

The effects of pregnancy on alveolar bone turnover during experimental tooth movement in rats (백서에서 실험적 치아이동시 임신이 치조골 교체(Turnover)에 미치는 영향에 대한 연구)

  • Kim, Young-Sun;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.30 no.4 s.81
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    • pp.413-421
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    • 2000
  • The purpose of this study was to observe the effects of pregnancy on the experimental tooth movement and alveolar bone turnover process of Sprague-Dawley female rat. Sixty rats were divided into pregnant-tooth movement group(P-Tm), normal-tooth movement group(N-Tm) and normal group(N). Maxillary first molar appliances were inserted bilaterally and activated to 40grams. To measure the amount of tooth movement, x-ray was taken 2 times after appliance insertion and before sacrifice. Animals were sacrificed at 1,3,7,14 days(N=5). Just after sacrifice, alveolar bones were collected and frozen immediately for biochemical analysis. Tooth movement was assessed cephalometrically and tartrate-resistant acid(TRAP) and alkaline phosphatase (ALP) activities were measured in extracts of paradental alveolar bone. The results were as follows: 1. The amount of tooth movement in P-Tm group was greater than that of N-Tm group(p<0.01). 2. Alveolar bone ALP of normal tooth movement group was not significantly different from the control, TRAP was significantly different from the control(p<0.01). In normal tooth movement group, alveolar bone ALP was increased gradually and peak(day 7) fell off significantly at day 14(p<0.05). The Peak of alveolar bone TRAP(day 7) fell off slightly, sustained day 14(p<0.01). 3. Alveolar bone ALP and TRAP of pregnant tooth movement group were not significantly different from that of normal tooth movement group. In pregnant tooth movement group, alveolar bone ALP was increased at day 3(p<0.01) and fell off significantly at day 7-14, alveolar bone TRAP were increased at day 3 and sustained day 14. 4. The peak of alveolar bone phosphatases in pregnant tooth movement group(day3) preceded the peak in normal tooth movement group(day7) (p<0.01). According to the above results, we suggested that bone resorption activity was increased in alveolar bone of pregnant rat, and the degree of tooth movement in pregnancy may be greater than that of normal group because of high bone turnover of alveolar bone in pregnant rat.

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Linolenic Acid in Association with Malate or Fumarate Increased CLA Production and Reduced Methane Generation by Rumen Microbes

  • Li, X.Z.;Choi, S.H.;Jin, G.L.;Yan, C.G.;Long, R.J.;Liang, C.Y.;Song, Man K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.6
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    • pp.819-826
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    • 2009
  • An in vitro study was conducted to investigate the effect of malate or fumarate on fermentation characteristics, and production of conjugated linoleic acid (CLA) and methane ($CH_4$) by rumen microbes when incubated with linolenic acid (${\alpha}-C_{18:3}$). Sixty milligrams of ${\alpha}-C_{18:3}$ alone (LNA), or ${\alpha}-C_{18:3}$ with 24 mM malic acid (M-LNA) or ${\alpha}-C_{18:3}$ with 24 mM fumaric acid (F-LNA) were added to the 150 ml culture solution consisting of 75 ml strained rumen fluid and 75ml McDougall's artificial saliva. Culture solution for incubation was also made without malate, fumarate and ${\alpha}-C_{18:3}$ (Control). Two grams of feed consisting of 70% concentrate and 30% ground alfalfa (DM basis) were also added to the culture solution of each treatment. In vitro incubation was made anaerobically in a shaking incubator up to 12 h at $39^{\circ}C$. Supplementation of malate (M-LNA) or fumarate (F-LNA) increased pH at 6 h (p<0.01) and 12 h (p<0.001) incubation times compared to control and linolenic acid (LNA) treatments. Both malate and fumarate did not influence the ammonia-N concentration. Concentration of total VFA in culture solution was higher for M-LNA and F-LNA supplementation than for control and LNA treatments from 6 h (p<0.040) to 12 h (p<0.027) incubation times, but was not different between malate and fumarate for all incubation times. Molar proportion of $C_3$ was increased by F-LNA and M-LNA supplementation from 6 h (p<0.0001) to 12 h (p<0.004) incubation times compared to control and LNA treatments. No differences in $C_{3}$ proportion, however, were observed between M-LNA and F-LNA treatments. Accumulated total gas production for 12h incubation was increased (p<0.0002) by M-LNA or F-LNA compared to control or LNA treatment. Accumulated $CH_4$ production for 12 h incubation, however, was greatly reduced (p<0.0002) by supplementing malate or fumarate compared to the control, and its production from M-LNA or F-LNA treatment was smaller than that from LNA treatment. Methane production from LNA, M-LNA or F-LNA treatment was steadily lower (p<0.01 - p<0.001) from 3 h incubation time than that from the control, and was also lower for M-LNA or F-LNA treatment at incubation times of 6 h (p<0.01) and 9 h (p<0.001) than for LNA treatment. Methane production from LNA, however, was reduced (p<0.01 - p<0.001) from 3 h to 9 h incubation times compared to the control. Both malate and fumarate increased concentration of trans11-$C_{18:1}$ from 3 h to 12 h incubation (p<0.01), cis9,trans11-CLA up to 6 h incubation (p<0.01 - p<0.01), trans10,cis12-CLA at 3 h (p<0.05) and 12 h (p<0.01), and total CLA for all incubation times (p<0.05) compared to corresponding values for the ${\alpha}-C_{18:3}$ supplemented treatment (LNA). In conclusion, malate and fumarate rechanneled the metabolic $H_2 pathway to production of propionate and CLA, and depressed the process of biohydrogenation and methane generation. Linolenic acid alone would also be one of the optimistic alternatives to suppress the $CH_4$ generation.