• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.128-135
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• 2022

Because construction work is conducted outdoors, construction workers are affected by harmful environmental factor. Especially, Particulate Matter (PM₁₀) is one of the harmful environmental factors with a diameter of 10㎍/m³ or less. When PM₁₀ is inhaled by human, it can cause fatal impact on the human. Contrary to the various analyses of health impact on PM₁₀, the research on the relationship between construction accidents and PM₁₀ are few. Therefore, this study aims to conduct the relative frequency analysis which find out the correlation between construction accidents and PM₁₀, and the modified PM₁₀ grade is suggested to expect accidents probability caused by PM₁₀ in the construction industry. This study is conducted by four steps. i) Establishment of the database; ii) Classification of data; iii) Analysis of the Relative Frequency of accidents in the construction industry by PM₁₀ concentration; iv) Modified PM₁₀ groups to classify the impact of PM₁₀ on accident. In terms of frequency analysis, the most accidents were occurred in the average concentration of PM₁₀ (32㎍/m³). However, we found that the relative frequency of accident was increased as the concentration of PM₁₀ increased. This means the higher PM₁₀ concentration can cause more accidents during construction. In addition, PM₁₀ concentration was divided as 6 groups by the WHO, but the modified PM₁₀ grade by the relative frequency on accident was suggested as 3 groups.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.533-539
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• 1992

Sixteen crossbred (Sahiwal $\times$ Holstein) male rumen fistulated calves of 18 to 24 months of age were randomly divided into four groups of four animal, each. Animals in all the groups were fed wheat straw ad lib as basal roughage. However, the animals in group I were fed concentrate mixture at maintenance level, whereas, the animals in groups II, III and IV had free access to existing, modified (A) and modified (B) urea molasses mineral block licks respectively. Daily wheat straw intake (kg) was significantly (p<0.01) higher in groups II ($4.20{\pm}0.13$), III ($4.07{\pm}0.16$) and IV ($4.22{\pm}0.20$) as compared to group I ($3.21{\pm}0.14$). Total N and TCA precistrained rumen liquor) was significantly higher in groups II ($22.36{\pm}0.25$), III ($21.63{\pm}0.25$) and IV ($21.77{\pm}0.55$) as compared to group I ($18.31{\pm}0.41$). Bacterial production rate (g/day and g/kg digestible organic matter intake) were non-significantly different amongst groups I ($214.4{\pm}13.28;\;85.38{\pm}3.69$); II ($198.7{\pm}5.70;\;86.17{\pm}3.53$); III ($214.4{\pm}8.19;\;96.15{\pm}2.16$) and IV ($218.2{\pm}10.62;\;94.44{\pm}5.52$). Similarly, percent efficiency of N incorporation into bacterial protein was not found significantly different amongst groups I, II, III and IV. These studies indicate that when concentrate mixture (upto maintenance level) in the diet of ruminants was replaced with UMMB licks, various N fraction in SRL and efficiency of bacterial production rates in the rumen were not affected.

• Journal of Chest Surgery
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• 제30권9호
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• pp.847-853
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• 1997

Although the effects of adenosine on the heart, including the clinical suppression of cardiac arrhythmias, have been recognized for more than half a century, it is only in the last decade that the therapeutic potential of adenosine has been recognized. The objective of this study was to determine if augmentation of myocardial adenosine levels during global ischemia improves functional recovery after reperfusion. We used to modified Langendonf system to evaluate myocardial protective effect. Isolated rat hearts were subjected to 90 minutes of deep hypothermic arrest(15$^{\circ}C$) with modified St. Thomas'Hospital cardioplegic solution used to provide myocardial protection. Myocardial adenosine levels were augmented during ischemia by providing exogenous adenosine in the cardioplegic solution. Two groups of hearts w re studied: (1) control group(n=10) cardioplegia alone; (2) adenosine group(n=10) adenosine(0.75mg/kg/min) added to the cardioplegic solution. Significantly better percent recovery(p<0.01) in hemodynamics(except heart rate) at 60 minutes after reperfusion was evident compared to baseline values in the adenosine group. (systolic no란ic pressure : 78.5$\pm$3.6% vs 66.6$\pm$5.9%, airtic overflow volume : 61.7$\pm$ 11.6% vs 37.2$\pm$ 15.4%, coronary flow volume 77.1$\pm$7.5% vs 57.2$\pm$ 11.1%, and cardiac output : 65.6$\pm$ 11.5% vs 44.2$\pm$ 12.4%). Heart rate was similar in two groups(94.4$\pm$4.8% vs 95.3 $\pm$ 6.8%). Adenosine groups resulted in significantly rapid recovery time of heart beat after reperEusion(p<0.01) (24.5$\pm$7.6 sec. vs 179.0$\pm$ 131.1sec.). In biochemical study, CPK levels(0.1 $\pm$0.3U/L vs 1.4$\pm$0.8U/L) and lactic acid levels(0.08$\pm$0.Immol/L vs 0.34$\pm$0.2 mmol/L) were significantly low in adenosine groups(p<0.01). We concluded that adenosine included cardioplegia have better recovery effects after r perfusion in myocardial ischemia compared to adenosine free cardioplegia.

• 한국임상수의학회지
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• 제16권1호
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• pp.1-7
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• 1999

The purpose of the present study was to evaluate the easiness of suture and fixation of modified total ring prostheses (m-TRP). Twelve healthy dogs (B.W.2-10 kg) were randomly assigned to three groups. In group A (3 dogs), total ring prostheses was fixed by penetrating a suture material through tracheal mucosa. In group B (3 dogs), TRP was fixed by suturing on tracheal cartilage and muscular layer not penetrating through tracheal mucosa. m-TRP was applied to the cervical portions (group M-C,3 dogs), and thoracic portions (group M-T,3 dogs). Operating time of group M-C (37.33$\pm$6.80 min.) was shorter than those of groups B (83.33$\pm$8.50 min.) and A (63.33$\pm$11.06 min.) (p＜0.01). Clinical complications were minimal and limited to mild, short-term hematoma, vomiting, edema, and inflammation. Coughing remarkably decreased in group B rather than group A. Dyspnea was not showed in group A, B, and M-C, but group M-T had a mild dyspnea. Gross postmortem findings were similar in all groups. Mild adhesions were present between prostheses and adjacent structures, but tracheal lumen was clean. Severe adhesions were present where m-TRP had been applied in the thoracic portions. Histopathologic abnormalities included mild to moderate adventitial and periprosthetic fibrosis and mild adventitial inflammation. The present study indicated that m-TRP were easier in suture and fixation than TRP and had no differences in support for trachea and side effects.

• Asian-Australasian Journal of Animal Sciences
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• 제25권2호
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• pp.170-176
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• 2012

Genetic diversities, population genetic structures and demographic histories of the thread-sail filefish Stephanolepis cirrhifer were investigated by nucleotide sequencing of 336 base pairs of the mitochondrial DNA (mtDNA) control region in 111 individuals collected from six populations in Korean coastal waters. A total of 70 haplotypes were defined by 58 variable nucleotide sites. The neighbor-joining tree of the 70 haplotypes was shallow and did not provide evidence of geographical associations. Expansion of S. cirrhifer populations began approximate 51,000 to 102,000 years before present, correlating with the period of sea level rise since the late Pleistocene glacial maximum. High levels of haplotype diversities ($0.974{\pm}0.029$ to $1.000{\pm}0.076$) and nucleotide diversities (0.014 to 0.019), and low levels of genetic differentiation among populations inferred from pairwise population FST values (-0.007 to 0.107), support an expansion of the S. cirrhifer population. Hierarchical analysis of molecular variance (AMOVA) revealed weak but significant genetic structures among three groups ($F_{CT}$ = 0.028, p<0.05), and no genetic variation within groups (0.53%; $F_{SC}$ = 0.005, p = 0.23). These results may help establish appropriate fishery management strategies for stocks of S. cirrhifer and related species.

• 대한치과교정학회지
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• 제40권6호
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• pp.432-443
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• 2010

이번 연구의 목적은 기존의 페이스 마스크와 변형된 페이스 마스크의 치아 및 골격적 효과를 평가하고자 III급 부정교합환에서 치료군과 비치료군을 비교하였다. 24명의 환자(여자: 13명, 남자: 11)로 구성된 기존의 페이스 마스크 그룹(Group 1, mean age, $9.2{\pm}1.4$ years)과 24명의 환자(여자: 12명, 남자: 12명)로 구성된 변형된 페이스 마스크(Group 2, mean age, $9.3{\pm}1.6$ years); 그리고 21 명(여자: 11 명, 남자: 10명)으로 구성된 대조군 그룹(Group 3, mean age, $9.8{\pm}1.9$ years)으로 분류하였다. 그룹 내 그룹 간에 치료군과 대조군을 통계학적으로 분석하였다. 그룹 내 비교는 비모수적인 방법의 Wilcoxon's test으로 그룹 간의 변화는 Kruskal-Wallis test를 이용하여 분석하였다. 이후 그룹 간의 통계적인 유효성 검증을 위하여 Mann-Whitney test와 Bonferroni's correction 을 시행하였다 (p < 0.016). Group 1에서 SNB 변화가 대조군보다 적었다. SNA, ANB, SN-MP, A to N perp과 Upper lip to E plane이 증가하였다. Group 2에서는 SNB, U1-NA (mm) U1-NA ($^{\circ}$) and Pog to N perp (mm) 변화는 대조군보다 적었다. SNA, ANB, SN-MP, A to N perp과 Upper lip to E plane이 증가하였다. 변형된 페이스 마스크는 상악 열성장이 있는 III급 부정교합 환자에게 효과적으로 사용될 수 있다. 상악궁 확장을 동반한 페이스 마스크를 통하여 상악은 회전을 야기시키지 않고 전방으로 이동하였으며 모든 치료군에서 하악은 후하방으로 이동하였다.

• Journal of Periodontal and Implant Science
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• 제29권3호
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• pp.621-636
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• 1999

When mucoperiosteal flaps are positioned and sutured to desirable position, the wound contains several interface between tissues which differ fundamentally in composition & biological reaction. Thus the C-T surface of the flap will, on one hand, oppose another vascularized surface, and on the other, the avascular dental material for example, when root resoptions, fractured root, endodontic perforation, deep root carious lesions were filled with amalgam, glass ionomer, resin etc. Recently, a number of case report described the successful treatment of a subgingival root lesion with restorative material & free gingival graft, open flap surgery, but more objective research was needed . Most of study on restorative materials were concerned for cytotoxicity not for actual healing event on that materials and its influencing factors such as biocompatibility, surface wettability, surface topography . The aim of this in vitro study was to evaluate the effect of amalgam, resin modified glass ionomer, composite resin per se, and their surface roughness on the growth of human gingival fibroblast. The cells were obtained and placed on culture flask and incubated for 3 days with the prepared test materials. Then count the attached cell number with hemocytometer,(n=12) and 2 samples were examined with SEM about attachment cell morphology . Another 4 samples were evaluated on their surface roughness with Talysurf and average surface roughness value(Ra) were obtained. Statistical difference in attached cell number, roughness value were analyzed using ANOVA. The number of attached cell was as follows, for root dentin specimen 16.7${\pm}$4.41, resin modified glass ionomer 14.0${\pm}$4.15, resin 8.13${\pm}$3.63, amalgam 0.72${\pm}$3.33(${\times}10^3$). Between root dentin and resin-modified glass ionomer, no significant difference was observed, but resin, amalgam showed a significant less cell numbers than for root dentin, resin modified glass ionomer cement. SEM examination expressed many cell surface attachment apparatus in root dentin and resin modified glass ionomer specimens. For resin specimen, cell attachment was observed but exposed less appratus. The average surface roughness value are following results. Dentin specimen 0.6972${\pm}$ 0.104, resin modified glass ionomer 0.0822${\pm}$0.009, resin 0.0875${\pm}$0.005, amalgam 4.2145${\pm}$0.985(${\mu}m$). Between root dentin, resin-modified glass ionomer, and resin, no significant difference was observed, but amalgam showed a significant more rough surface than other groups. When evlauated the interrelationship between cell attachment and surface roughness, therefore, there was weak reverse correlation.(pearson correlation : - 0.593) These results suggest that resin modified glass ionomer have the favorable healing potential when used for subgingival restoration. And for relationship between cell attachment and surface characteristics, further investigations were needed.

• 동아시아식생활학회지
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• 제7권3호
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• pp.365-374
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• 1997

The purpose of this study was to assess the effect of nutrition education by the difference of BMI(Body Mass Index) group for adults at rural area. Eighty four adults (mean age : 55.9$\pm$11.8) participated in nutrition education program. Data collection includes measured physical status and serum collections for health status. The impact of nutrition KAP (knowledge attitude and practice) and retention was examined among participants who were assessed at program entry, 3 times of education and 1 month of follow-up. The results were as follows: The participants were composed 14 persons of under 20kg/$m^2$ of BMI, 40 persons of 20-25 and 27 persons over 25 of BMI , female 60 persons but male 23 only. Serum albumin and calcium content of female(3.5$\pm$1.2g/㎗, 7.5$\pm$3.9mg/㎗) were significantly lower than males(4.7$\pm$0.9g/㎗, 11.2$\pm$4.6mg/㎗) but there was not significantly different with BMI groups. Serum TG and cholesterol contents of over 25kg/$m^2$ of BMI group(157$\pm$87mg/㎗, 249$\pm$16mg/㎗) were higher than other groups, but significantly different in cholesterol contents only. Via the 10 questions of nutrition attitude, the participants improved significantly between pre and post education(the score of pre, post and after 1 month, 6.5$\pm$1.8, 7.2$\pm$1.5, 7.2$\pm$1.9), and were also attributed to better personal feeling health by modified CMI test, but dietary food habit was not significantly improved. As the differences of BMI groups were compared, 20-25kg/$m^2$ group had better the effect of nutrition education score than other groups, and female had better nutrition attitude and practice score than male.

• Membrane and Water Treatment
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• 제10권2호
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• pp.113-120
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• 2019

To investigate surface properties and interception performances of the new modified PVDF membrane coated with Graphene Oxide (GO) and nano-$TiO_2$ (for short the modified membrane) via the interface polymerization method combined with the pumping suction filtration way, filtration experiments of the modified membrane on Humic Acid (HA) were conducted. Results showed that the contact angle (characterizing the hydrophilicity) of the modified membrane decreased from $80.6{\pm}1.8^{\circ}$ to $38.6{\pm}1.2^{\circ}$. The F element of PVDF membrane surface decreased from 60.91% to 17.79% after covered with GO and $TiO_2$. O/C element mass ratio has a fivefold increase, the percentage of O element on the modified membrane surface increased from 3.83 wt% to 20.87%. The modified membrane surface was packed with hydrophilic polar groups (like -COOH, -OH, C-O, C=O, N-H) and a functional hydrophilic GO-polyamide-$TiO_2$ composite configuration. This configuration provided a rigid network structure for the firm attachment of GO and $TiO_2$ on the surface of the membrane and for a higher flux as well. The total flux attenuation rate of the modified membrane decreased to 35.6% while 51.2% for the original one. The irreversible attenuation rate has dropped 71%. The static interception amount of HA on the modified membrane was $158.6mg/m^2$, a half of that of the original one ($295.0mg/m^2$). The flux recovery rate was increased by 50%. The interception rate of the modified membrane on HA increased by 12% approximately and its filtration cycle was 2-3 times of that of the original membrane.

• The Journal of Advanced Prosthodontics
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• 제4권3호
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• pp.127-133
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• 2012

PURPOSE. Many dentists use desensitizing agents to prevent hypersensitivity. This study compared and evaluated the effect of two desensitizing agents on the retention of cast crowns when cemented with various luting agents. MATERIALS AND METHODS. Ninety freshly extracted human molars were prepared with flat occlusal surface, 6 degree taper and approximately 4 mm axial length. The prepared specimens were divided into 3 groups and each group is further divided into 3 subgroups. Desensitizing agents used were GC Tooth Mousse and $GLUMA^{(R)}$ desensitizer. Cementing agents used were zinc phosphate, glass ionomer and resin modified glass ionomer cement. Individual crowns with loop were made from base metal alloy. Desensitizing agents were applied before cementation of crowns except for control group. Under tensional force the crowns were removed using an automated universal testing machine. Statistical analysis included one-way ANOVA followed by Turkey-Kramer post hoc test at a preset alpha of 0.05. RESULTS. Resin modified glass ionomer cement exhibited the highest retentive strength and all dentin treatments resulted in significantly different retentive values (In Kg.): GLUMA ($49.02{\pm}3.32$) > Control ($48.61{\pm}3.54$) > Tooth mousse ($48.34{\pm}2.94$). Retentive strength for glass ionomer cement were GLUMA ($41.14{\pm}2.42$) > Tooth mousse ($40.32{\pm}3.89$) > Control ($39.09{\pm}2.80$). For zinc phosphate cement the retentive strength were lowest GLUMA ($27.92{\pm}3.20$) > Control ($27.69{\pm}3.39$) > Tooth mousse ($25.27{\pm}4.60$). CONCLUSION. The use of $GLUMA^{(R)}$ desensitizer has no effect on crown retention. GC Tooth Mousse does not affect the retentive ability of glass ionomer and resin modified glass ionomer cement, but it decreases the retentive ability of zinc phosphate cement.