• Title/Summary/Keyword: Primary retention

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Comparison of Nitrogen Removal in Reed Wetlands with and Without Open Water Purifying Effluent from a Treatment Pond (하천수를 정화하는 갈대습지의 개수부에 의한 질소제거 비교)

  • Yang, Hongmo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.1
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    • pp.37-44
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    • 2005
  • Nitrate($NO_3-N$) and total nitrogen(TN) removal by a reed wetland with open water(Wetland 1) was compared with that of a reed wetland without open water(Wetland 2) from March to October 2002. The two wetlands were 25mL by 6mW. An open water area, 3mL by 6mW was designed at the middle of Wetland 1. Reeds(Phragmites australis) were transplanted into the wetlands in June 2000. Water of Sinyang Stream flowing into the Kohung Estuarine Lake located in the southern part of Korea was pumped into a primary treatment pond, whose effluent was discharged into the secondary pond. Effluent from the secondary pond was funneled into the wetlands. Inflow into the wetlands averaged about 20.0$m^3$/day and their hydraulic retention time was approximately 1.5 days. Average $NO_3-N$ removal by Wetland 1 was 117.61mg/$m^2{\cdot}day$ and that by Wetland 2 was 106.39mg/$m^2{\cdot}day$. $NO_3-N$ removal efficiency of Wetland 1 and 2 was 37% and 34%, respectively. TN removal by Wetlands 1 and 2 averaged 226.80 and 214.54mg/$m^2{\cdot}day$, respectively. TN abatement efficiency of Wetland 1 was 43% and that of Wetland 2 was 40%. $NO_3-N$ removal efficiency of Wetland 1 was significantly higher(p=0.038) than Wetland 2. TN removal efficiency of Wetland 1 was also significantly higher(p=0.044) than Wetland 2. The wetland with open water was more efficient for removal of $NO_3-N$ and TN than one without.

MANDIBULAR EXPANSION IN A CONGENITAL AGLOSSIA PATIENT (선천적 무설증 환자에서의 하악골 확장)

  • Cho, Jae-Yong;Kim, Jung-Wook;Jang, Ki-Taeg;Kim, Chong-Chul;Hahn, Se-Hyun;Lee, Sang-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.30 no.4
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    • pp.673-677
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    • 2003
  • Congenital aglossia is a very rare condition. The oral manifestations of an aglossia include micrognathia, high arched or cleft palate, defects of the lower lip, an absence of lateral incisors and a mandibular growth deficiency. Although the etiology of congenital aglossia is unclear, both genetic and teratogenic mechanisms have been proposed. Treatment of aglossia patients depends on the nature and severity of the condition which includes surgical rehabilitation of the tongue tip to some extent, orthopedic expansion of the mandible to guide mandibular growth, and mandibular expansion by a distraction osteogenesis. In the present case, a 6 year old female aglossia patient with situs inversus was treated. A bonded hyrax screw was used to increase her mandibular primary intercanine width and intermolar width. A second phase orthodontic and surgical treatment will be possible after some retention phase.

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A Study on Drawing Priority of Competitiveness Factors of Ship Management Company in Korea Using AHP (AHP를 이용한 우리나라 선박관리기업의 경쟁력 요인 우선순위 도출에 관한 연구)

  • Lee, Chang-Ho;Ryoo, Dong-Keun;Sohn, Bo-Ra;Seo, Young-Joon
    • Journal of Navigation and Port Research
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    • v.34 no.3
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    • pp.243-249
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    • 2010
  • The competition between ship management companies is fierce as a result of global trend towards increased specialization. In order for ship management companies to remain competitive, it is necessary to understand the local and global factors and the changing circumstances that impact shipping markets and trade patterns. To better understand these factors, a study and analysis of drawing priority of the competitiveness-evaluation factors of ship management companies was conducted using Analytical Hierarchy Process(AHP) as a method dealing with dicision-making problem. As a consequence of this analysis, it was determined that human resources, both shipboard and land management, were a primary factor in ship management company's competitiveness. Thus, the acquisition and retention of capable staff was a key aspect of assuring a ship management company's competitiveness.

Graphene/Multi-Walled Carbon Nanotubes Hybrid Materials for Supercapacitors

  • Lee, Bo-Reum;Chang, Dong Wook
    • Clean Technology
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    • v.21 no.1
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    • pp.62-67
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    • 2015
  • We have developed a versatile method for the preparation of chemically linked graphene/multi-walled carbon nanotubes (MWNTs) hybrid materials via simple acid-catalyzed dehydration reaction between graphene oxide (GO) and amine-functionalized MWNTs (af-MWNTs). In this condition, ketone (-C=O) groups in GO and primary amine (-NH2) moieties in af-MWNTs readily react to form imine (-C=N-) linkage. The chemical structures of graphene/MWNTs hybrid materials have been investigated using various microscopic and spectroscopic measurements. As a result of the synergetic effects of hybrid materials such as improved surface area and the superior structural restoration of graphitic networks, the hybrid materials demonstrate improved capacitance with excellent long-term stability. Furthermore, controlled experiments were conducted to optimize the weight ratio of graphene/MWNTs in hybrid materials. The highest capacitance of 132.4 F/g was obtained from the GM7.5 material, in which the weight ratio between graphene and MWNTs was adjusted to 7.5/1, in 1M KOH electrolyte at a scan rate of 100 mV/s.

Chuna Manual Therapy on Gynecologic Disease: A Systematic Review and Meta-analysis (부인과 질환에 대한 추나 요법: 체계적 문헌 고찰 및 메타분석)

  • Yeon-Woo Lee;Jae-Uk Sul;Jin-Hyun Lee;Dong-Chan Jo;Yun-Kyung Song;Man-Suk Hwang
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.17 no.2
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    • pp.27-37
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    • 2022
  • Objectives This study aimed to investigate the clinical trial trends of Chuna manual therapy (CMT) on gynecologic disease and suggest the effectiveness and safety evidence for further study. Methods We searched nine electronic databases (CENTRAL, CiNii, CNKI, EMBASE, KMbase, KISS, MEDLINE PubMed, NDSL, and OASIS) using the search terms "Chuna" and "Tuina" and identified relevant literature that investigated the CMT as an intervention for gynecologic disease. All relevant papers were extracted and selected to be analyzed. Results Among the 1456 studies that were searched and screened, 18 randomized controlled trials (RCTs) satisfied the designated criteria. A meta-analysis showed that CMT had a curative effect on patients with primary dysmenorrhea, postpartum hypogalactia, breast hyperplasia, postpartum urinary retention, and pelvic pain. Conclusions Based on this study, CMT should be comprehensively considered for gynecologic disease. The treatment response was significantly enhanced after treatment; however, there were some limitations in the study. More well-designed RCTs are needed to ensure that all gynecologic patients have a safe and effective therapy.

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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    • v.53 no.3
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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.

Applicability Evaluation of Nitritation with Various Wastewater (다양한 하수를 대상으로 아질산화 반응 적용성 평가)

  • Im, Jiyeol;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.17 no.1
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    • pp.11-18
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    • 2015
  • As the seriousness of water pollution resulted from nitrogen is being magnified, research has been conducted to reduce nitrogen in sewage as well as wastewater. Particularly research on innovative nitrogen removal methods that are based on the reaction of nitritation and are economically feasible and eco-friendly has been receiving attention. However, research on the applicability and efficiency of the methods based on the reaction of nitritation has not been completely done yet. Accordingly, the current study has analyzed the characteristics of sewage flowing into municipal wastewater treatment plants, primary clarifier supernatant, recycled water, and livestock wastewater and also operated a laboratory-level reactor. The result shows that recycled water and livestock wastewater contain higher-concentration nitrogen than other kinds of sewage, so they increase nitrogen loading in the water treatment line. And the result of operating a reactor shows that because of ammonium nitrogen low concentration, sewage and primary clarifier supernatant do not induce the reaction of nitritation. Also, there exist differences in the conditions of retention time inducing the reaction of nitritation by the types of sewage, and this seems to be attributed to organic compound and ammonium nitrogen concentration. Among the kinds of sewage inducing the reaction of nitritation, anaerobic digester supernatant indicates the highest efficiency.

ERUPTION GUIDANCE FOR TOOTH GERM OF PREMOLAR DISPLACED BY INFRAOCCLUDED UPPER DECIDUOUS MOLAR (저위교합된 상악 유구치에 의해 변위된 소구치 치배의 맹출유도)

  • Jung, Jung-Hwa;Kim, Young-Jin;Kim, Hyun-Jung;Nam, Soon-Hyeun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.39 no.4
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    • pp.390-396
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    • 2012
  • Infraocclusion is defined as tooth whose relative occlusal movement was blocked during the period of active eruption due to ankylosis and so on. Then infraoccluded tooth remains under the occlusal plane composed by adjacent structures showing normal eruption patterns. Untreated infraocclusion may cause: prolonged retention of infraoccluded teeth; extrusion of apposed teeth; destruction of periodontal tissues by occlusal force and food packing; increased sensitivity for dental caries; and disturbances on eruption pathway of succedaneous teeth. Therefore, periodic check-ups and proper treatments are required. There are many treatment options on infraoccluded deciduous molars such as periodic observation, conservative method, restoration and space regaining with extraction of the teeth. The choice of treatment may depend on the presence of succedaneous teeth, time of diagnosis and degree of infraocclusion. In this case report, three patients showing displacement of the second premolars due to infraocclusion of upper second primary molars, were treated by means of space regaining with removable orthodontic appliances and extraction of ankylosed primary molars. All malpositioned permanent premolars in the 3 cases showed ordinary eruption pathways after treatment.

Cellular and Molecular Pathology of Fungi on Plants Studied by Modern Electron Microscopy

  • Sanwald, Sigrun-Hippe
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 1995.06b
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    • pp.27-53
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    • 1995
  • In plant pathology there is an increasing necessity for improved cytological techniques as basis for the localization of cellular substances within the dynamic fine structure of the host-(plant)-pathogen-interaction. Low temperature (LT) preparation techniques (shock freezing, freeze substitution, LT embedding) are now successfully applied in plant pathology. They are regarded as important tools to stabilize the dynamic plant-pathogen-interaction as it exists under physiological conditions. - The main advantage of LT techniques versus conventional chemical fixation is seen in the maintenance of the hydration shell of molecules and macromolecular structures. This results in an improved fine structural preservation and in a superior retention of the antigenicity of proteins. - A well defined ultrastructure of small, fungal organisms and large biological samples such as plant material and as well as the plant-pathogen (fungus) infection sites are presented. The mesophyll tissue of Arabidopsis thaliana is characterized by homogeneously structured cytoplasm closely attached to the cell wall. From analyses of the compatible interaction between Erysiphe graminis f. sp. hordei on barley (Hordeum vulgare), various steps in the infection sequence can be identified. Infection sites of powdery mildew on primary leaves of barley are analysed with regard to the fine structural preservation of the haustoria. The presentation s focussed on the ultrastructure of the extrahaustorial matrix and the extrahaustorial membrane. - The integration of improved cellular preservation with a molecular analysis of the infected host cell is achieved by the application of secondary probing techniques, i.e. immunocytochemistry. Recent data on the characterization of freeze substituted powdery mildew and urst infected plant tissue by immunogold methodology are described with special emphasis on the localization of THRGP-like (threonine-hydrxyproline-rich glycoprotein) epitopes. Infection sites of powdery mildew on barley, stem rust as well as leaf rust (Puccinia recondita) on primary leaves of wheat were probed with a polyclonal antiserum to maize THRGP. Cross-reactivity with the anti-THRGP antiserum was observed over the extrahaustorial matrix of the both compatible and incompatible plant-pathogen interactions. The highly localized accumulation of THRGP-like epitopes at the extrahaustorial host-pathogen interface suggests the involvement of structural, interfacial proteins during the infection of monocotyledonous plants by obligate, biotrophic fungi.

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Evaluation of removal forces of implant-supported zirconia copings depending on abutment geometry, luting agent and cleaning method during re-cementation

  • Rodiger, Matthias;Rinke, Sven;Ehret-Kleinau, Fenja;Pohlmeyer, Franziska;Lange, Katharina;Burgers, Ralf;Gersdorff, Nikolaus
    • The Journal of Advanced Prosthodontics
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    • v.6 no.3
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    • pp.233-240
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    • 2014
  • PURPOSE. To evaluate the effects of different abutment geometries in combination with varying luting agents and the effectiveness of different cleaning methods (prior to re-cementation) regarding the retentiveness of zirconia copings on implants. MATERIALS AND METHODS. Implants were embedded in resin blocks. Three groups of titanium abutments (pre-fabricated, height: 7.5 mm, taper: $5.7^{\circ}$; customized-long, height: 6.79 mm, taper: $4.8^{\circ}$; customized-short, height: 4.31 mm, taper: $4.8^{\circ}$) were used for luting of CAD/CAM-fabricated zirconia copings with a semi-permanent (Telio CS) and a provisional cement (TempBond NE). Retention forces were evaluated using a universal testing machine. Furthermore, the influence of cleaning methods (manually, manually in combination with ultrasonic bath or sandblasting) prior to re-cementation with a provisional cement (TempBond NE) was investigated with the pre-fabricated titanium abutments (height: 7.5 mm, taper: $5.7^{\circ}$) and SEM-analysis of inner surfaces of the copings was performed. Significant differences were determined via two-way ANOVA. RESULTS. Significant interactions between abutment geometry and luting agent were observed. TempBond NE showed the highest level of retentiveness on customized-long abutments, but was negatively affected by other abutment geometries. In contrast, luting with Telio CS demonstrated consistent results irrespective of the varying abutment geometries. Manual cleaning in combination with an ultrasonic bath was the only cleaning method tested prior to re-cementation that revealed retentiveness levels not inferior to primary cementation. CONCLUSION. No superiority for one of the two cements could be demonstrated because their influences on retentive strength are also depending on abutment geometry. Only manual cleaning in combination with an ultrasonic bath offers retentiveness levels after re-cementation comparable to those of primary luting.