• 제목/요약/키워드: attachment material

검색결과 269건 처리시간 0.025초

담체의 소수성과 표면 거칠기가 미생물 부착에 미치는 영향 (Effect of the Hydrophobicity and the Surface Roughness of Support Material on the Microbial Attachment)

  • 박영식;서정호;송승구
    • 한국환경과학회지
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    • 제6권6호
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    • pp.689-696
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    • 1997
  • This paper discussed effect of the surface roughness and the hydrophobicity of support material on the microbial attachment In a rotating biological contactor. The by- drophoblclty of each support material was determined by the measurement of contact angle of water and the surface roughness was measured by the surface roughness In- strument. Microorganisms have well attached on the surface of more hydrophilic support material like Nylon6 than that of the hydrophobic support material like PE. When the relatively hydrophilic surface was roughen, the microbial attachment was increased but when the relatively hydrophobic surface was roughen, the attachment was slightly In- creased because the hydrophobicity of support material was Increased by roughening the hydrophobic surface. Although both variables, the surface hydrophobicity and the surface roughness, have Influenced the microbial attachment, the influence of the surface roughness overruled that of the surface hydrophobicity. Support material whose surfaces were roughened about 1mm, 6mm and 11mm were allowed for attached 3, 7 and 24hr, but the differences of maximum and minimum attachment of each material gave nearly constant values and similar trend with time.

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Comparative Evaluation of the Fluoride Releasing Ability and Microbial Attachment of Glass-Hybrid Restorative Material

  • MinKi Choi;Howon Park;Siyoung Lee;Haeni Kim;Juhyun Lee
    • 대한소아치과학회지
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    • 제51권2호
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    • pp.132-139
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    • 2024
  • This study aimed to compare the fluoride-releasing ability and degree of microbial attachment of a newly developed glass-hybrid restorative material (GH) with those of a high-viscosity glass ionomer (HvGIC), resin-modified glass ionomer (RMGI), and composite resin (CR). In addition, the correlation between fluoride-releasing ability and microbial attachment between materials was evaluated. Specimens were prepared in a disc shape and divided into 4 groups according to the materials (GH, HvGIC, RMGI, and CR). The fluoride release experiments were performed in each group (n = 15). The amount of fluoride released was measured on days 1, 3, 7, 14, 28, and 42 after storage. For the microbial attachment experiment, 12 specimens were produced per group using Mutans Streptococci (S.mutans ), a cariogenic microorganism. S. mutans was cultured on the specimens for 24 hours, and the number of bacteria was measured. GH had the highest cumulative fluoride release and showed a significant difference when compared with RMGI (p = 0.001) and CR (p < 0.0001). Microbial attachment was the lowest in GH; however, no significant difference was observed between the materials (p = 0.169). There was no significant correlation between fluoride release from materials and microbial attachment (p > 0.05). From this perspective, remineralization of low-mineralized areas could be expected due to the high fluoride release of GH, and the effect of delaying the progression of dental caries could be predicted from the low cariogenic microbial attachment. Therefore, GH might be a useful restorative material for treating immature permanent teeth with hypomineralized enamel. However, further studies are needed about the degree of remineralization of hypomineralized areas after restoration and the capacity to recharge fluoride.

타인 양육 영아-어머니 애착에 대한 생태학적 연구 (An Ecological Study on Infant-Mother Attachment in a Nonmaternal Care)

  • 양연숙
    • 대한가정학회지
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    • 제40권7호
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    • pp.1-14
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    • 2002
  • This study investigated infant, mother/famny, and nonmaternal care characteristics contribution to infant- mother attachment through ecological perspective. Participants were forty 12-to 18-month-o1d infants and their mothers. Infants were observed in the Strange Situation to assess the pattern of infant-mother attachment; the Observational Ratings of the Caregiving Environment was used to assess the caregiving environment. Mothers were interviewed with the questionnaires, and observed in the laboratory "living room". There were significant effects of material sensitivity/responsiveness and good quality child care on secure attachment. Infant, mother/family, and nonmaternal care characteristics were mutually related.

Quality of life, patient preferences, and implant survival and success of tapered implant-retained mandibular overdentures as a function of the attachment system

  • Ilze Indriksone;Pauls Vitols;Viktors Avkstols;Linards Grieznis;Kaspars Stamers;Susy Linder;Michel Dard
    • Journal of Periodontal and Implant Science
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    • 제53권3호
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    • pp.194-206
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    • 2023
  • Purpose: A novel attachment system for implant-retained overdentures (IRODs) with novel material combinations for improved mechanical resilience and prosthodontic success (Novaloc) has been recently introduced as an alternative to an existing system (Locator). This study investigated whether differences between the Novaloc and Locator attachment systems translate into differences in implant survival, implant success, and patient-centered outcomes when applied in a real-world in-practice comparative setting in patients restored with mandibular IRODs supported by 2 interforaminal implants (2-IRODs). Methods: This prospective, intra-subject crossover comparison compared 20 patients who received 2 intra-foraminal bone level tapered implants restored with full acrylic overdentures using either the Locator or Novaloc attachment system. After 6 months of function, the attachment in the corresponding dentures was switched, and the definitive attachment system type was delivered based on the patient's preference after 12 months. For the definitive attachment system, implant survival was evaluated after 24 months. The primary outcomes of this study were oral health-related quality of life and patient preferences related to prosthetic and implant survival. Secondary outcomes included implant survival rate and success, prosthetic survival, perceived general health, and patient satisfaction. Results: Patient-centered outcomes and patient preferences between attachment systems were comparable, with relatively high overall patient satisfaction levels for both attachment systems. No difference in the prosthetic survival rate between study groups was detected. The implant survival rate over the follow-up period after 24 months in both groups was 100%. Conclusions: The results of this in-practice comparison indicate that both attachment systems represent comparable candidates for the prosthodontic retention of 2-IRODs. Both systems showed high rates of patient satisfaction and implant survival. The influence of material combinations of the retentive system on treatment outcomes between the tested systems remains inconclusive and requires further investigations.

The influence of parent-child attachment on child's servant leadership -focused on mediator effect of self-efficacy-

  • Seo, Jung-Sook;Cho, Sung-je
    • 한국정보전자통신기술학회논문지
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    • 제10권6호
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    • pp.570-579
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    • 2017
  • The purpose of this study is to examine the mediator effect of child self-efficacy in the influence of parent-child attachment on child's servant leadership. The study subjects were 260 parents and teachers attending child education institution Ulsan. The survey was conducted from 1st July 2016 to 29th July 2016. As a result, first, parent-child attachment did not have influence on servant leadership, but it did have influence on child-s self-efficacy. Second, in relationship between parent-child attachment and servant leadership, child's self-efficacy showed to play mediator role. This study will be the fundamental material for improving parent-child attachment and child's servant leadership.

CNC 공작기계 장착형 고속스핀들을 이용한 고속가공 실용화 기술 (High-speed Machining Technology using CNC Machining Center Equipped with Attachment Type High-Speed Spindle)

  • 이용철;곽태수;김경년;이종열
    • 한국기계가공학회지
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    • 제11권2호
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    • pp.152-158
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    • 2012
  • A newly developed attachment type high-speed spindle can be easily attached to the conventional CNC machining center to allow high-speed machining with low investment costs. This study has focused on the application of a conventional CNC machining center equipped with an attachment type high-speed spindle. A specimen of plastic mold material has been machined to compare the cutting effectiveness of the high-speed machining center and the conventional machining center with the attachment type high-speed spindle respectively. The rotational accuracy of the spindles are measured by a transmission optic measurement system and the surface roughness of the workpiece in accordance with revolution speed(rpm) of the spindle are investigated respectively. As the experimental results, it was shown that the surface roughness of the machined workpiece was $3.42{\mu}mR_{max}$, $0.46{\mu}mR_a$ in the case of attachment type spindle and $1.81{\mu}mR_{max}$, $0.275{\mu}mR_a$ in the case of the high-speed machining center. Moreover, the mean rotational accuracy was $7.57{\mu}m$ in the case of the attachment type spindle and $7.39{\mu}m$ in the case of the high-speed machining center.

고분자 물질 도포가 미생물 부착과 생물막 성장에 미치는 영향 (Effect of Polymer Coating on the Initial Microorganism Attachment and the Biofilm Growth)

  • 박영식;송승구
    • 한국환경보건학회지
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    • 제24권2호
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    • pp.104-109
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    • 1998
  • The objective of this study was to examine the effect of polymer coating on the initial microorganism attachment and the biofilm growth. Such as nonion(polyacrylamine), anion(CMC-Na) and cation polymer coagulant(chitosan and PEI) were used for coating material of the support carrier(acryl plate). When polymer coagulant was coated with 5, 10, 20, 35, 50, 100 and 200 mg/l on the surface of acryl plate, initial microorganism attachment increased and optimum concentration for the attachment was 35 mg/l. Biofilm growth experiments were conducted with the substrate loading of 12.7gSCOD/$m^2\cdot$ day using RBC. The polymer coagulants such as CMC-Na, polyacrylamide, PEI and chitosan coating on the acryl plate facilitated the biofilm growth of microorganisms. Until the biofilm dry weight grows up to 0. 0038g/cm$^2$, biofilm growth on the plate coated with cation polymer like chitosan was better than that on the coated plate of nonion(polyacrylamine), anion(CMC-Na) polymer coagulant.

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전문병원 역량이 고객 행동 의도에 미치는 영향 연구 (The Effects of Special Hospital Competencies on Customer Behavior Intentions)

  • 소권섭
    • 보건의료산업학회지
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    • 제7권4호
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    • pp.153-165
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    • 2013
  • This study aims to analyze how the competencies of specialized hospitals affect the customer behavior intentions. The research involved 14 specialized hospitals among 42 nationwide, which are selected by the Ministry of Health and Welfare in 2007. The results of the study are below. First, the competencies of specialized hospitals are emotional attachment and customer satisfaction proved to have the significant relationship. Second, the competencies of human resources and technology-related resources has a moderating effect with accessibility while the ability of material effect doesn't have such relation. Third, it was verified that the emotional attachment formed the customer satisfaction. Fourth, it turned out that the emotional attachment and customer satisfaction has the significant influence on customer behavior intentions. In conclusion, the competencies of specialized hospitals influences on the customer behavior intentions through the mediating effects of emotional attachment and customer satisfaction.

표면염화물량 산정을 위한 건축마감재별 비래염분 부착율 분석 (Attachment Rate Analysis of Airborne Chlorides by Construction Finish Material to Measure the Amount of Chlorides on the Surface)

  • 조규환;지동헌;정재민;박동천
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
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    • pp.57-58
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    • 2014
  • For durability design to protect against chloride-induced corrosion, it is important to estimate the amount of chlorides on the surface. However, it is difficult to estimate the airborne chlorides, a boundary condition, due to the difference between the amount of chlorides attached to a surface of an actual structure and that in the air. Therefore, in this study the attachment rate analysis of airborne chlorides was evaluated for 13 types of finish materials. As a result, despite differences in the amount of airborne chlorides according to the finishing type, it was found that 60 percent of airborne chlorides were attached to mortar, 30 percent were attached to steel, and 25 percent were attached to tiles compared with the amount of chlorides in the air.

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WEAR BEHAVIOR OF ATTACHMENTS FOR IMPLANT RETAINED OVERDENTURE ACCORDING TO MATERIAL IN VITRO

  • Lee Seok-Hyung
    • 대한치과보철학회지
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    • 제41권6호
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    • pp.747-761
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    • 2003
  • Statement of problem. The proper materials of attachments for implant retained overdenture are unknown, such as the correlation between retention and abrasion, as well as the types of materials that are suitable for patrix and for matrix individually. Purpose of this study. The aim of this study was to select a proper clinical attachment system for a successful treatment as well as patient satisfaction. Methods. Retention and abrasion of 14 commercial attachments were measured during 15,000 removes. Results. A retentive part (matrix) which requires elasticity has to be made of gold while the patrix part which does not require elasticity has to be made of titanium. This gold matrix / titanium patrix combination showed the most retentive force and the least retention loss.