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Notes on Powdery mildew of Ailanthus altissima caused by Phyllactinia corylea (Pers.) Karst (Phyllactinia corylea (Pers.) Karst에 의(依)한 가중나무 흰가루병(病))

  • Kim, Ki Chung
    • Journal of Korean Society of Forest Science
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    • v.4 no.1
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    • pp.9-13
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    • 1965
  • Powdery mildew of Ailanthus altissima Sw. was first reported by J.S. Park in Korea, 1961. According to his report, this disease was found on the leaves of this tree species collected in Jeongup, 1957, and in Taejon, 1958. He described morphological characters of this pathogen and described also that the causal fungus may be closely related with Phyllactinia corylea. This disease which appears dusty grayish yellow molds under surface of leaves was collected again by the author in Kwangju, 1962. The present works were undertaken to make clear the species of causal fungus by means of the morphology and pathogenecity. According to the following results, the pathogen was identified as Phyllactinia corylea (Pers.) Karst. Morphological characters of the fungus Mycelia persistent or more or less evanescent; matured conidia solitary, aseptate, short-clavate to clavate to clavate, hyaline or yellowish, granulate, $44.6-89.2{\times}9.3-24.2{\mu}$, average $64.8-17.8{\mu}$ in size; conidiophores elongate clavate or columnar, hyaline, 2-3 septate, $122.8-346.0{\times}3.7-7.4{\mu}$, average $208.8{\times}6.3{\mu}$; per-thecia usually scattered, rarely gregarious, dark brown to black, depressed globose to globose, $223.2-297.6{\mu}$, average $267.8{\mu}$ in diameter; appendages 12-19, usually 15 in number, hyaline, straight, needle-shaped, sharply pointed at the apex and bulbous at the base, aseptate, $93.0-310.0{\times}5.0-8.0{\mu}$, average $173.3{\times}6.4{\mu}$ in size; asci elongate ellipsoidal to broadly clavate, hyaline, more or less stalked, 8-13 in number, $68.5-76.6{\times}26.1-34.2{\mu}$, average $71.4{\times}29.0{\mu}$ in size; ascospores 2-4, usually 2 in number, hyaline or yellowish, aseptate, ellipsoidal or ovate, $27.7-34.2{\times}14.7-17.9{\mu}$, average $25.5{\times}13.9{\mu}$ in size. Pathogenicity of the fungi In order to make clear the species of the fungus and the pathogenic differences of Phyllactinia fungi which are collected around the contaminated area and seemed to be related to Ailanthus powdery mildew, some inoculation experiments were performed. 1. Cross inoculation to several tree species with their pathogen: Tested materials; Phyllactinia in question on Ailanthus altissima Sw. Ph. fraxini (DC.) Homma. On Alnus firma S. et Z. Ph. moricola (P. Henn.) Homma on morus alba L. According to the results of the experiments, the reactions were all negative with the exception of the original hosts of tested fungi. 2. Inoculation to Picrasma ailanthoides Planch. : The appearance of symptom on the leaves of P. ailanthoides is not distinct, but more or less mycelial growth. Therefore, under the optimal condition in glass chamber, it may be possible to success artificially.

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Development of a Flavor-Enriched Yeast Extract with a High Glutathione Content (글루타치온 고함유 정미성 효모추출물 개발)

  • Bae, In-Young;Koo, Seung-Hyun;Yoo, Hyun-Jae;Kim, Jong-Min;Bae, Hyun-Ah;Jeon, Eun-Jung;Oh, Eon;Lee, Dae-Hee;Hur, Byung-Serk;Lee, Hyeon-Gyu
    • Korean Journal of Food Science and Technology
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    • v.42 no.5
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    • pp.549-553
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    • 2010
  • Yeast strains with good sensory properties were selected, and those yeasts were subjected to mutation to develop high glutathione producing yeasts. In addition, the antiradical activity and flavoring effect of the yeast extract were evaluated. A total of 68 strains were screened, and three strains of Saccharomyces utilis, four strains of Candida utilis, and one strain of Zygosaccharomyces rouxii were selected based on the flavoring effect. Among them, a random mutation was elicited against SEM-Y8, resulting in a high flavoring effect and growth rate. The glutathione production by SEM-Y8 increased 2.0-fold following the mutation, and the DPPH radical quenching effect of the SY8-M2-1-derived extract increased 3.2-fold compared to that of the wild type. The sensory properties of the SY8-M2-1-derived extract were better than those of garlic or onion extract in umami and mouthfulness. Thus, the SY8-M2-1 extract could be used as a functional flavoring material with improved antiradical activity.

The Crystal and Molecular Structure of P-Aminobenzaldehyde Cyclohexylthiosemicarbazone (P-Aminobenzaldehyde Cyclohexylthiosemicarbazone의 결정 및 분자구조)

  • Chung Hoe Koo;Chong Hee Kim;Young Ja Park
    • Journal of the Korean Chemical Society
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    • v.25 no.6
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    • pp.343-350
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    • 1981
  • The crystal and molecular structure of P-aminobenzaldehyde cyclohexylthiosemicarbazone, C14H20N4S, has been determined from 2712 integrated intensities measured on a computer controlled four circle diffractometer with monochromated $CuK_{\alpha}$, X-ray radiation. The crystals are monoclinic, space group C2/c with eight molecules in a unit cell of dimensions, a = 12.488(2), b = 12.276(4), c = 19.997(6)${\AA}$ and ${\beta}=103.55(3)^{\circ}$. The structure was solved by Patterson and Fourier method and refined by a full-matrix least squares method to a final R value of 0.058 for all reflections. The C(8)-S bond is trans to N(2)-N(3) and C(8)-N(1) is cis to N(2)-N(3) bond. The cyclohexane ring has chair conformation and makes an angle of $40.7^{\circ}$ with the benzene ring. The molecules are linked by N(2)H…S hydrogen bonds into dimer-like units which are held together by $N-H{\ldots}N$ hydrogen bonds. Sulfur accepts second rather weak hydrogen bond from N(4). An intramolecular hydrogen bond exists between N(1) and N(3) atoms.

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A STUDY ON MICROLEAKAGE OF COMPOSITE RESIN AFTER SURFACE TREATMENT (표면 처리방법에 따른 복합레진의 미세누출에 관한 실험적 연구)

  • Lee, Chang-Woo;Kim, Jung-Wook;Lee, Sang-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.1
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    • pp.103-115
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    • 1998
  • Adhesion of composite resin to tooth structure has been of tremendous signgicance in clinical dentistry. Due to the lack of adhesion between composite restorative resins and enamel and dentin, microleakage occurs at the tooth/restoration interface. This may lead to discoloration, secondary caries, marginal breakdown, postoperative sensitivity, and even pulpal pathology. According to extensive use of composite resin, every effort on improving bonding strength and reducing microleakage between a tooth and composite resin has been continued. This study was conducted to determine the difference in microleakage in enamel and dentin treated with air-abrasion, acid etching and combination when restored with composite resin. Class V cavities were prepared on 30 premolars. The specimens were divided into following groups. group 1:air-abrasion+Scotchbond Multi-purpose group 4 :air-abrasion+All-Bond 2 group 2:acid etching+Scotchbond Multi-purpose group 5 :acid etching+All-Bond 2 group 3:combination+Scotchbond Multi-purpose group 6 :combination+All-Bond 2 #combination:air-abrasion + acid etching The specimens were filled with Z-100 after application of Scotchbond Multi-purpose and All-Bond 2. Thermocycling was conducted by alternately dipping the specimens in $5^{\circ}C$ and $55^{\circ}C$ water for 30 seconds 500 times. 1% methylene blue was applied and the specimens were left for 24 hours at $37^{\circ}C$. After washing out the dye, the tooth was sectioned buccolingually along the axis. The sectioned surface was observed with stereoscope for dye penetration. The author has measured the microleakage in teeth prepared with air-abrasion, acid ethching and combination to study the difference in microleakage following different methods of tooth surface treatment and has come to following results. 1. In comparing microleakage between groups, group 1 and 4 showed statistically significant difference from group 2, 3, 5 and 6(p<0.05). There was no significant difference among group 2, 3, 5, 6(p>0.05) nor between group 1 and 4(p>0.05). 2. In comparing microleakage among tooth surface treatment methods, Air-abrasion group showed significantly more microleakage than acid etching group and combination(airabrasion + acid etching) group(p<0.05). Combination(acid etching+air-abrasion)group tended to show lesser microleakage than acid etching group, but this was not statistically significant(p>0.05). 3. In comparing microleakage between bonding agents, there was no statistically significant difference between Scotch bond Multi-purpose and All-Bond 2(p>0.05).

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A Study on Selective Metal Ion Sensing Membrane for Bio Environment Measurement (바이오 환경측정용 선택적 금속이온 감지 막의 특성 연구)

  • Park, Hyung-Jun;Jang, Gab-Soo;Kim, In-Su
    • Journal of IKEEE
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    • v.22 no.4
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    • pp.1062-1067
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    • 2018
  • In this study, the research processed with a chemical sensor for measuring trace amount of heavy metal ions which is based on the requirements of the efficient sensing technology as recent equipment is applies molecular system in the chemical sensing section that can precisely recognizing selective target substance and transmit its data to physical signal as a result. In this research is concentrated on realize highly precise by utilizing SPR sensor application of recognition functional sensing membrane. Consequently, according to DTSQ-dye sensing membrane, the resonance angle from low-concentration to the highest concentration $10^{-4}M$ of $Ag^+$ ion is $2.17[^{\circ}]$ and this result indicating 4.3 times larger resonance angle changes compare to the other metal substance. Based on SQ-dye sensing membrane, the difference of resonance angle between low concentration and the highest concentration $10^{-4}M$ of $Cu^{2+}$ ion is $2.3[^{\circ}]$ and this outcome is indicating 4.5 times greater resonance angle change to the other metal substance.

Impacts of Relative Advantage of Fast Food Restaurant's O2O Service and Consumer Involvement on Consumer Engagement, and Store Loyalty: Focused on MZ Generationsin Untact Consumption Era

  • LEE, Young-Eun;LEE, Yong-Ki
    • The Korean Journal of Franchise Management
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    • v.11 no.2
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    • pp.41-51
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    • 2020
  • Purpose: Fast food franchise companies are trying a variety of innovative services to increase their competitiveness in response to changes in population composition in the fast food market and rapid changes in consumption trends due to technological development. From this point of view, franchise companies that have focused on offline store operations are providing O2O (offline to online) service as a core service for customer convenience. This new attempt is a strategy to increase loyalty by applying an interaction method based on understanding the characteristics of new generation consumers. However, existing studies are focused on the relationship between O2O service and acceptance, so very little is known about how O2O service affects customer loyalty. Therefore, this study examines the impacts of customer involvement and relative advantages of fast food O2O service on customer brand engagement (cognitive and affective engagement) and store loyalty for MZ(Millennials - Z) generations. Research design, data, and methodology: In order to achieve the purposes of this research, several hypotheses were developed. The data were collected from 247 questionnaires in their 16-30s and were analyzed using SPSS 22.0 and SmartPLS 3.0 program. Measurement model analysis was carried out to assess convergent and discriminant validity. Also, common method bias was tested using the values of VIF (variance inflation factor). The hypotheses was tested using structural equation modeling. Result: First, involvement has a positive effect on cognitive and affective engagement. Second, relative advantages have has a positive effect on cognitive and affective engagement. Third, cognitive influences affective engagement. Finally, both cognitive and affective engagement affect store loyalty, but affective engagement has a stronger effect on store loyalty than cognitive engagement. Conclusions: In the process of consumer-brand interaction, it was confirmed that store loyalty was influenced by cognitive and affective engagement sequentially. However, the results show that affective engagement has a relatively stronger on store loyalty than cognitive engagement. Therefore, it is necessary to establish an O2O service strategy to maintain long-term loyal customers by inducing cognitive participation with high-involved consumer, as well as affective interaction, in order to obtain new customers and increase customer loyalty.

A study on the ecological habitat and protection of natural Sorbus commixta forest at Mt. Seorak (설악산(雪嶽山)에 분포(分布)하는 마가목 천연림(天然林)의 생태환경(生態環境)과 보호(保護)에 관(關)한 연구(硏究))

  • Shin, Jai Man;Kim, Tong Su;Han, Sang Sup
    • Journal of Forest and Environmental Science
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    • v.3 no.1
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    • pp.1-9
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    • 1983
  • The purpose of this study was to elucidate the ecophysiological habitat of natural Sorbus commixta forest at Mt. Seorak. The results obtained were as follows: 1. The Sorbus commixta trees mainly distributed from 900m to 1,500m altitude. In there, the warm index(WI) was about 42$3.2{\times}10^3$ to $9.2{\times}10^3$, cation exchange capacity(CEC) was 13.7 to 19.5mg/100g, N content 0.21 to 0.39%, $P_2O_5$ content was 22.6 to 38.7ppm, and pH value was 5.6 to 5.8 respectively. 4. The upper crown trees in Sorbus commixta communities were Abies nephrolepis, Taxus cuspidata, Betula platyphylla var. japonica, Quercus${\times}$grosseserrata, Acer mono, Prunus sargentii, Carpinus cordata, Tilia amurensis, and the under crown trees were Rhododendron brachycarpum, Acer pseudo-sieboldianum, Thuja olientalis, Corylus heterohpylla, Philadelphus schrenckii, Rhododendron schlippenbachii, Rhododendron mucronulatum, and Magnolia sieboldii. 5. The stand densities were 1,156 trees/ha at 1,160m and 3,600 trees/ha at 1,300m respectively. The coverages by the DBH basal area were 0.37 at 1,160m and 0.31 at 1,300m respectively, and the vegetation coverages by the crown projection area were 2.04 at 1,160m and 1.61 at 1,300m respectively. 6. The light extinction coefficient(k) in Beer-Lambert's law, showed the distance, F(z), from top canopy to aboveground, was 0.17. 7. The water relations parameters of Sorbus commixta shoot were obtained by the pressure chamber technique. The osmotic pressure, ${\pi}_o$, at maximum turgor was -16.2 bar, and VAT pressure was 14.5bar. The osmotic pressure, ${\pi}_p$, at incipient plasmolysis was -19.4bar. The relative water contents at incipient plasmolysis were 83.1% ($v_p/v_o$) and 87.1%($v_p/w_s$;$w_s$, total water at maximum turgor). 8. The bulk modulus of elasticity(E) of shoot was about 69.6. The total symplasmic water to total water in shoot was 67.7%, and the apoplastic water to total water was 32.3%.

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Shear bond strength of dental CAD-CAM hybrid restorative materials repaired with composite resin (치과용 복합레진으로 수리된 CAD-CAM hybrid 수복물의 전단결합강도)

  • Moon, Yun-Hee;Lee, Jonghyuk;Lee, Myung-Gu
    • The Journal of Korean Academy of Prosthodontics
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    • v.54 no.3
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    • pp.193-202
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    • 2016
  • Purpose: This study was performed in order to assess the effect of the surface treatment methods and the use of bonding agent on the shear bond strength (SBS) between the aged CAD-CAM (computer aided design-computer aided manufacturing) hybrid materials and added composite resin. Materials and methods: LAVA Ultimate (LU) and VITA ENAMIC (VE) specimens were age treated by submerging in a $37^{\circ}C$ water bath filled with artificial saliva (Xerova solution) for 30 days. The surface was ground with #220 SiC paper then the specimens were divided into 9 groups according to the combination of the surface treatment (no treatment, grinding, air abrasion with aluminum oxide, HF acid) and bonding agents (no bonding, Adper Single Bond 2, Single Bond Universal). Each group had 10 specimens. Specimens were repaired (added) using composite resin (Filtek Z250), then all the specimens were stored for 7 days in room temperature distilled water. SBS was measured and the fractured surfaces were observed with a scanning electron microscope (SEM). One-way ANOVA and Scheffe test were used for statistical analysis (${\alpha}=.05$). Results: Mostly groups with bonding agent treatment showed higher SBS than groups without bonding agent. Among the groups without bonding agent the groups with aluminum oxide treatment showed higher SBS. However there was no significant difference between groups except two subgroups within LU group, which revealed a significant increase of SBS when Single Bond Universal was used on the ground LU specimen. Conclusion: The use of bonding agent when repairing an aged LAVA Ultimate restoration is recommended.

Synthesis of ${\alpha}$-Alumina Nanoparticles Through Partial Hydrolysis of Aluminum Chloride Vapor (염화알미늄 증기의 부분가수분해를 통한 알파 알루미나 나노입자 제조)

  • Park, Hoey Kyung;Yoo, Youn Sug;Park, Kyun Young;Jung, Kyeong Youl
    • Korean Chemical Engineering Research
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    • v.49 no.5
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    • pp.664-668
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    • 2011
  • Spherical alumina precursors represented by $AlO_xCl_y(OH)_z$, 30~200 nm in particle diameter, were prepared by partial hydrolysis of $AlCl_3$ vapor in a 500 ml reactor. Investigated on the particle morphology and size were the effects of the reaction time, the stirring speed and the reaction temperature. The particle morphology and size was insensitive to the reaction time in the range 20 to 300 s. The variation of the stirring speed from 0 to 300 and 800 rpm showed that the particle size was the largest at 0 rpm. As the temperature was varied from 180 to 190, 200, $140^{\circ}C$, the particle size showed a maximum at $190^{\circ}C$. By calcination of the as-produced particles at $1,200^{\circ}C$ for 6h with a heating rate of $10^{\circ}C$/min, ${\alpha}$-alumina particles 45 nm in surface area equivalent diameter were obtained. The particle shape after calcination turned wormlike due to sintering between neighboring particles. A rapid calcination at $1400^{\circ}C$ for 0.5 h with a higher heating rate of $50^{\circ}C$/min reduced the sintering considerably. An addition of $SiCl_4$ or TMCTS(2,4,6,8-tetramethylcyclosiloxane) to the $AlCl_3$ reduced the sintering effectively in the calcination step; however, peaks of ${\gamma}$ or mullite phase appeared. An addition of $AlF_3$ to the particles obtained from the hydrolysis resulted in a hexagonal disc shaped alumina particles.

Kinematic Analysis of Airborne Movement of Dismount from High Bar(I) (철봉 내리기 공중 동작의 운동학적 분석(I))

  • Choi, Ji-Young;Kim, Youg-Ee;Jin, Young-Wan
    • Korean Journal of Applied Biomechanics
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    • v.12 no.2
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    • pp.159-177
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    • 2002
  • The purpose of this study was to investigate the relations between the segments of the body, the three dimensional anatomical angle and the angular velocity of the air born phase and understand the control mechanism of the high-bar movement, the somersault, the double somersault, the double somersault with full twist. For this study seven well trained university gymnastic volunteered, Zatsiorky and Seluyanov(1983, 1985)'s sixteen segment system anatomical model was used for this study. For the movement analysis three dimensional cinematographical method(Arial Performance Analysis System : APAS) was used and for the calculation of the kinematic variables a self developed program was used with the LabVIEW 5.1 graphical profromming(Johnson, 1999) program. By using Eular's equations the three dimensional anatomical Cardan angles of the joint and angular velocity were defined. As a result of this study 1. As the rotation of the body increased in the air born phase the projection angle of the CM of the total increased, this resulted the increased of the max hight of the CM. 2. In three dimensional angular velocity the Z axis(vertical direction) projection angular velocity increased as the rotation of the body increased in the airborn phase, but the Y axis and the X axis projection angular velocity did not show significant differences. 3. As the rotation of the body increased in the air born phase the angular movement of the shoulder and the hip showed significant change. These movement act as the starter in the preparation phase. 4. The somersault angle, the twist angle, the tilt angle of the upper body related to the global reference frame in the releas phase the average somersault angle of the three types of high-bar movement was $57.7^{\circ}$, $38.8^{\circ}$, $39.7^{\circ}$, the average tilt angle was $-1.5^{\circ}$, $-5.4^{\circ}$, $-8.4^{\circ}$, the average twist angle was $13.4^{\circ}$, $10.6^{\circ}$, $23.3^{\circ}$. This result showed that the somersault with full twist had the largest movement.