• Membrane and Water Treatment
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• v.6 no.3
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• pp.237-249
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• 2015

In this study we investigate a laboratory scale vacuum membrane distillation system to produce pure water from model oil in water emulsion. Experimental determination of liquid entry pressure (LEP) of a commercial Durapore$^{TM}$ GVPH flat sheet membrane using model emulsions in various oil concentrations has been carried out. Two different methods of liquid entry pressure determination - a frequently used, so-called static and a novel dynamic method - have been investigated. In case of static method, LEP value was found to be 2.3 bar. No significant effect of oil content on LEP was detected up to 3200 ppm. In contrast, LEP values determined with dynamic method showed strong dependence on the oil concentration of the feed and decreased from 2.0 bar to a spontaneous wetting at 0.2 bar in the range 0-250 ppm, respectively. Vacuum membrane distillation tests were also performed. The separation performance is evaluated in terms of flux behavior, total organic carbon removal and droplet size distribution of the feed and final retentate. No significant effect of oil content on the flux was found ($5.05{\pm}0.31kgm^{-2}h^{-1}$) up to 250 ppm, where a spontaneous wetting occurred. High separation performance was achieved along with the increasing oil concentration between 93.4-97.0%.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.6
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• pp.293-298
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• 2015

Objectives: Infection involving the orbit, zygomatic space, lateral pharyngeal space, or hemifacial and oral floor phlegmon is referred to as cervicofacial infection (CFI). When diagnosis and/or adequate treatment are delayed, these infections can be life-threatening. Most cases are the result of odontogenic infections. We highlight our experiences in the management of this life-threatening condition. Materials and Methods: This was a retrospective study of patients who presented with CFI from December 2005 to June 2012 at the Oral and Maxillofacial Surgery Clinic or the Accident and Emergency Unit of Ahmadu Bello University Teaching Hospital (Zaria, Nigeria). The medical records of all patients who presented with either localized or diffuse infection of the maxillofacial soft tissue spaces were retrospectively collected. Data collected was analyzed using SPSS version 13.0 and are expressed as descriptive and inferential statistics. Results: Of the 77 patients, 49 patients (63.6%) were males, a male to female ratio of 1:7.5. The ages ranged from two years to 75 years with a mean of $35.0{\pm}19.3$ years, although most patients were older than 40 years. The duration of symptoms prior to presentation ranged from 6 to 60 days, with a mean of $11.0{\pm}9.4$ days. More than 90% of the patients presented to the clinic within the first 10 days. The most commonly involved anatomical space was the submandibular space (n=29, 37.7%), followed by hemifacial space (n=22, 28.6%) and buccal space (n=7, 9.1%). Ludwig angina accounted for about 7.8% of the cases. Conclusion: CFI most commonly involves the submandibular space, typically affects individuals with a low level of education, and is influenced by traditional medical practices. Despite improved health care delivery, CFI remains a significant problem in developing countries.

• Journal of architectural history
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• v.24 no.1
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• pp.29-40
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• 2015

This study is on historiography of Modern Architecture since its beginning to present. As a critical review of the history of the writing history of Modern Architecture, this study tends to be a meta-history and criticism of historical text. This study try to analyse historiographical project of Modern architecture at specific phase since the beginning of modern architecture. The historiography of Modern architecture shows that writing a history is making a discourse of Modern architecture as a imaginative representation to define and justify Modernism in architecture. The analysis of canonic text since early 20th century proves that the history of writing history of Modern architecture played a critical role not only to shape of our ideal but the practice of architecture with a ideology construction in retrospect. With a name of truth or morality they made myths about the modernity in architecture. So we can find deep 'Hagelean Unconscious' in writing history of Modern architecture not even the first generation of historians but the second generation who were influenced by earlier writer in spite of their intention of revision and overcoming, which is in itself the key concept of Hegel's philosophy of History. Under this kind of 'operative' discourse our view point of Modern architecture were confined and the historiography of Modern architecture itself was narrowly defined as a kind of melodrama that a few architect and work of art matters. The rise of critical history fundamentally has changed the way of seeing and writing the history of Modern architecture. but it has also a new kind of dilemma as regard to writing history and involving practice. This review of historiography traces the texts of historians as like Pevsner, Giedion, Banham, Rowe, Tafuri, Frampton, and Curtis relating to different discours making. When we consider Benjamin's famous concept of constellation, writing history necessarily is a kind of montage making in time and we always need to recognize the historicity of historiography.

• Advances in environmental research
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• v.2 no.2
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• pp.155-166
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• 2013

A preliminary investigation to establish the status of contamination of trace metals in the Western coast of Ghana was conducted prior to the commercial production of crude oil in the area. The study revealed the presence of heavy metals such as Pb (4.00-79.64 mg/kg), As (8.81-236 mg/kg), Cu (12.86-108.06 mg/kg), V (28.07-953.32 mg/kg), Zn (7.08-264.25 mg/kg), Cr (101.69-1366.62 mg/kg), Ni (42.41-451.43 mg/kg), Mn (16.77-1890.45mg/kg), Br (7.66-142.78 mg/kg), Ti (542.03-19960 mg/kg) and Fe (7472.88-97120 mg/kg) at six sites sampled along the coast. With the exception of Ti and Fe which showed no variation in metal concentration, the rest of the metals varied significantly among the sampled locations. Potential ecological risk of metals particularly of Co, As and Br which exhibited extreme enrichment of the sediments indicates considerable metal pollution in the studied areas. The degree of contamination is of particular concern especially to benthic biota that inhabit this environment for survival.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.221-226
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• 2006

Around 2002, the United States Coast Guard (USCG) identified a need to re-capitalize their Reference Station (RS) and Integrity Monitor (IM) equipment used in the Nationwide Differential Global Position System (NDGPS). Commercially available off-the-shelf differential RS and IM equipment lacked the open architecture required to support long-term goals that include future system improvements such as use of new civil frequencies on L2 and L5 and realization of a higher rate NDGPS beacon data channel intended to support RTK. The first step in preparing for this future NDGPS was to port current RTCM SC-104 compatible RS and IM functionality onto an open architecture PC-based platform. Trimble's product Charisma is a PC-based RS and IM software designed to meet these USCG goals. In fact USCG engineers provided key designs and design insights throughout the development. We cannot overstate the contribution of the USCG engineers. Fundamental requirements for this effort were that it be sufficiently flexible in hardware and software design to support fluid growth and exploitation of new signals and technologies as they become available, yet remain backward compatible with legacy user receivers and existing site hardware and system architecture. These fundamental goals placed an implicit adaptability requirement on the design of the replacement RS and IM. Additionally, project engineers were to remain focused on sustaining the high level of differential GPS service that 1.5 million legacy users have come to depend on. This paper will present new hardware and software (i.e., Trimble's Charisma software) architecture for the next generation NDGPS RS and IM. This innovative approach to engineering on an open architecture PC-based platform allows the system to continue to fulfill legacy NDGPS system requirements and allows the USCG and others to pursue a scalable hardware re-capitalization strategy. We will use the USCG's recapitalization project to explain the essential role of the Charisma software.

• Restorative Dentistry and Endodontics
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• v.45 no.2
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• pp.23.1-23.12
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• 2020

Objectives: This study aimed to summarize the outcome of in vitro studies comparing the antibacterial effectiveness of QMix with other irrigants against Enterococcus faecalis. Materials and Methods: The research question was developed by using population, intervention, comparison, outcome, and study design framework. The literature search was performed using 3 electronic databases: PubMed, Scopus, and EBSCOhost until October 2019. The additional hand search was performed from the reference list of the eligible studies. The risk of bias of the studies was independently appraised using the revised Cochrane Risk of Bias tool (RoB 2.0). Results: Fourteen studies were included in this systematic review. The overall risk of bias for the selected studies was moderate. QMix was found to have a higher antimicrobial activity compared to 2% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), mixture of tetracycline isonomer, an acid and a detergent (MTAD), 0.2% Cetrimide, SilverSol/H2O2, HYBENX, and grape seed extract (GSE). QMix had higher antibacterial efficacy compared to NaOCl, only when used for a longer time (10 minutes) and with higher volume (above 3 mL). Conclusions: QMix has higher antibacterial activity than 17% EDTA, 2% CHX, MTAD, 0.2% Cetrimide, SilverSol/H2O2, HYBENX, GSE and NaOCl with lower concentration. To improve the effectiveness, QMix is to use for a longer time and at a higher volume.

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.28.1-28.13
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• 2020

Objectives: To evaluate the outcome of in vitro studies comparing the effectiveness of QMix irrigant in removing the smear layer in the root canal system compared with other irrigants. Materials and Methods: The research question was developed by using Population, Intervention, Comparison, Outcome and Study design framework. Literature search was performed using 3 electronic databases PubMed, Scopus, and EBSCOhost until October 2019. Two reviewers were independently involved in the selection of the articles and data extraction process. Risk of bias of the studies was independently appraised using revised Cochrane Risk of Bias tool (RoB 2.0) based on 5 domains. Results: Thirteen studies fulfilled the selection criteria. The overall risk of bias was moderate. QMix was found to have better smear layer removal ability than mixture of tetracycline isonomer, an acid and a detergent (MTAD), sodium hypochlorite (NaOCl), and phytic acid. The efficacy was less effective than 7% maleic acid and 10% citric acid. No conclusive results could be drawn between QMix and 17% ethylenediaminetetraacetic acid due to conflicting results. QMix was more effective when used for 3 minutes than 1 minute. Conclusions: QMix has better smear layer removal ability compared to MTAD, NaOCl, Tubulicid Plus, and Phytic acid. In order to remove the smear layer more effectively with QMix, it is recommended to use it for a longer duration.

• Journal of the Institute of Convergence Signal Processing
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• v.7 no.2
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• pp.81-86
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• 2006

In this paper, a new process detection circuit is proposed. The proposed process detection circuit compares a long channel MOS transistor (L > 0.4um) to a short channel MOS transistor which uses lowest feature size of the process. The circuit generates the differential current proportional to the deviation of carrier mobilities according to the process variation. This method keep the two transistor's drain voltage same by implementing the feedback using a high gain OPAMP. This paper also shows the new design of the simple high gam self-biased rail-to-rail OPAMP using a proposed self-biased super MOS composite circuit. The gain of designed OPAMP is measured over 100dB with $0.2{\sim}1.6V$ wide range CMR in single stage. Finally, the proposed process detection circuit is applied to a differential VCO and the VCO showed that the proposed process detection circuit compensates the process corners successfully and ensures the wide rage operation.

• The Journal of Art Theory & Practice
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• no.5
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• pp.25-41
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• 2007

Despite continuous efforts to redraw the boundaries between art and culture, the conventional concept of originality has persisted in approaches to the practice of contemporary art. In the discourse of originality, various forms of lesser arts that employ the method of replication have been referred to as kitsch, or "rear-guard," the opposite of avant-garde. This categorization points to the contested issue regarding the oppositional relation between modernism and mass culture. With its easily accessible content and financial affordability, mass culture has become both an irresistible attraction and a most powerful threat to modernism. This threat has instigated a discursive system that has situated mass culture as a cultural other of modernism. Taking the marginalized category of kitsch as the area of contention, this paper examines a discursive repression of kitsch. It analyzes the conceptual framework that defends originality and autonomy in art and, conversely, degrades kitsch as an inferior and dangerous cultural category. Greenberg'S concept of kitsch as a by-product of industrialization evolved into the criticism that advocates the autonomy of art. The Frankfurt School scholars, particularly Theodor Adorno and Max Horkheimer, practiced comparable cultural critiques. Focusing on mass culture such as film, radio, and television, instead of art works, they critically analyzed the system of mass culture and theorized the negative implications of the ubiquitous presence of kitsch. Some critics, on the other hand, perceived the growth of mass culture as opening possibilities in cultural development. Walter Benjamin and Harold Rosenberg asserted the socio-cultural dynamics of mass culture underlining the potential for continual transformation in reality and in the subject. They acknowledged that technological advances changed the condition of creation and enabled unmediated interactions between media. By scrutinizing conflicting views on kitsch, this paper intends to reassess arts that draw "the forces of the outside."

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.5
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• pp.351-359
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• 2021

Objectives: Despite treatment, the pre-traumatic facial appearance of patients with maxillofacial fractures might not be able to be restored, and this difference can affect the person's quality of life (QoL). This study was designed to evaluate changes in QoL of people with maxillofacial fractures. Materials and Methods: The study population was comprised of participants with maxillofacial fracture and age- and sex-matched healthy controls without history of such fracture. QoL was measured using the World Health Organization Quality of Life BREF (WHOQOL-BREF) questionnaire, which was administered to the patients before treatment (Time 1), at 6 weeks post-treatment (Time 2), and at 12 weeks postoperatively (Time 3). The values were compared with those of healthy controls. The QoL was compared between closed reduction group and open reduction and internal fixation group. Results: The QoL scores of people with maxillofacial fracture before treatment were significantly lower (P=0.001) than those of healthy controls in all domains of the WHOQOL-BREF. The QoL scores in the psychological and social domains of patients with maxillofacial fracture at Time 3 were still lower than those of healthy controls (P=0.001). Conclusion: The QoL of patients with maxillofacial fracture was significantly reduced before treatment in all domains and remained reduced in both psychological and social domains weeks after treatment. Therefore, clinicians must be aware of and manage the residual psychosocial issues that can accompany the post-treatment period of maxillofacial injury.