Peel strength of denture liner to PMMA and polyamide: laser versus air-abrasion

Korkmaz, Fatih Mehmet,Bagis, Bora,Ozcan, Mutlu,Durkan, Rukiye,Turgut, Sedanur,Ates, Sabit Melih The Korean Academy of Prosthodonitics 2013 The Journal of Advanced Prosthodontics Vol.5 No.3

PURPOSE. This study investigated the effect of laser parameters and air-abrasion on the peel strength of silicon-based soft denture liner to different denture resins. MATERIALS AND METHODS. Specimens (N=180) were prepared out of three different denture base resins (Rodex, cross-linked denture base acrylic resin; Paladent, heat-cured acrylic resin; Deflex, Polyamide resin) ($75mm{\times}25mm{\times}3mm$). A silicon-based soft denture liner (Molloplast B) was applied to the denture resins after the following conditioning methods: a) Air-abrasion ($50{\mu}m$), b) Er,Cr:YSGG laser (Waterlase MD Turbo, Biolase Technology) at 2 W-20 Hz, c) Er,Cr:YSGG laser at 2 W-30 Hz, d) Er,Cr:YSGG laser at 3 W-20 Hz, e) Er,Cr:YSGG laser at 3 W-30 Hz. Non-conditioned group acted as the control group. Peel test was performed in a universal testing machine. Failure modes were evaluated visually. Data were analyzed using two-way ANOVA and Tukey's test (${\alpha}$=.05). RESULTS. Denture liner tested showed increased peel strength after laser treatment with different parameters ($3.9{\pm}0.4-5.58{\pm}0.6$ MPa) compared to the control ($3.64{\pm}0.5-4.58{\pm}0.5$ MPa) and air-abraded groups ($3.1{\pm}0.6-4.46{\pm}0.3$ MPa), but the results were not statistically significant except for Paladent, with the pretreatment of Er,Cr:YSGG laser at 3 W-20 Hz. Polyamide resin after air-abrasion showed significantly lower peel strength than those of other groups ($3.1{\pm}0.6$ MPa). CONCLUSION. Heat-cured acrylic resin, PMMA, may benefit from Er,Cr:YSGG laser treatment at 3 W-20 Hz irradiation. Air-abrasion of polyamide resins should be avoided not to impair their peel bond strengths to silicon-based soft denture liners.

Hypoparathyroidism in children and adolescents

Korkmaz Hüseyin Anıl,Ozkan Behzat 대한소아내분비학회 2023 Annals of Pediatirc Endocrinology & Metabolism Vol.28 No.3

Hypoparathyroidism is characterized by insufficient parathyroid hormone (PTH) release from the parathyroid glands to maintain serum calcium level within normal limits and unresponsiveness of target tissues despite normal serum PTH level. Hypoparathyroidism is defined as low or inappropriately normal serum PTH level. In this narrative review, we discuss the etiology of hypoparathyroidism in children.

Reliability of Stool Antigen Tests: Investigation of the Diagnostic Value of a New Immunochromatographic Helicobacter pylori Approach in Dyspeptic Patients

Korkmaz, Huseyin,Findik, Duygu,Ugurluoglu, Ceyha,Terzi, Yuksel Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.2

Background: A diagnosis of H. pylori infection can be made by invasive or non-invasive methods. Several noninvasive diagnostic tests based on the detection of H. pylori stool antigen (HpSA) have been developed. The Genx H. pylori stool antigen card test is a new rapid, non-invasive test that is based on monoclonal immunochromatographic assay. The aim of this study was to determine its sensitivity, specificity, and diagnostic accuracy for diagnosing H. pylori infection in adult patients. Materials and Methods: A total of 162 patients were included in the study. A gastric biopsy was collected for histopathology and rapid urease testing. Stool specimens for HpSA testing were also collected. Patients were considered H. pylori positive if two invasive tests (histological and rapid urease tests) were positive. Results: Using the reference test, 50.6% of the samples were positive for H. pylori infection. The Genx H. pylori antigen test was positive in 19.7% of patients. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the Genx H. pylori antigen test were 51.6%, 96.0%, 88.8%, 76.1%, and 79.0%, respectively. Conclusions: The Genx H. pylori stool antigen card test is a new non-invasive method that is fast and simple to perform but provides less reliable results.

THE INVESTIGATION OF BURNUP CHARACTERISTICS USING THE SERPENT MONTE CARLO CODE FOR A SODIUM COOLED FAST REACTOR

Korkmaz, Mehmet E.,Agar, Osman Korean Nuclear Society 2014 Nuclear Engineering and Technology Vol.46 No.3

In this research, we investigated the burnup characteristics and the conversion of fertile $^{232}Th$ into fissile $^{233}U$ in the core of a Sodium-Cooled Fast Reactor (SFR). The SFR fuel assemblies were designed for burning $^{232}Th$ fuel (fuel pin 1) and $^{233}U$ fuel (fuel pin 2) and include mixed minor actinide compositions. Monte Carlo simulations were performed using Serpent Code1.1.19 to compare with CRAM (Chebyshev Rational Approximation Method) and TTA (Transmutation Trajectory Analysis) method in the burnup calculation mode. The total heating power generated in the system was assumed to be 2000 MWth. During the reactor operation period of 600 days, the effective multiplication factor (keff) was between 0.964 and 0.954 and peaking factor is 1.88867.

The Epidemiological and Clinical Characteristics of 81 Children with COVID-19 in a Pandemic Hospital in Turkey: an Observational Cohort Study

Korkmaz Muhammet Furkan,Türe Esra,Dorum Bayram Ali,Kılıç Zeliha Banu 대한의학회 2020 Journal of Korean medical science Vol.35 No.25

Background: Coronavirus disease-2019 (COVID-19) pandemic has affected millions of people throughout the world since December 2019. However, there is a limited amount of data about pediatric patients infected with the disease agent, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods: The epidemiological, laboratory, radiological, and treatment features of the pediatric patients who were positive for SARS-CoV-2 based on the reverse-transcription polymerase chain reaction (RT-PCR) test, were investigated retrospectively. Results: The median age of 81 children included in the study was 9.50 years (0–17.75 years). The most frequent symptoms at the time of admission were fever (58%), cough (52%), and fatigue or myalgia (19%). The abnormal laboratory findings in these cases were decreased lymphocytes (2.5%, n = 2), leucopenia (5%, n = 4), and increased lactate dehydrogenase (17.2%, n = 14), C-reactive protein (16%, n = 13), procalcitonin (3.7%, n = 3), and D-dimer (12.3%, n = 10). Three (4%) patients had consolidation in chest computed tomography, and three (4%) had ground-glass opacities. None of the patients needed intensive care except for the newborns. The median time to turn SARS-CoV-2 negative in the RT-PCR test was 5 (3–10) days. The median length of hospital stay was 5 (4–10) days. The time to turn SARS-CoV-2 negative in the RT-PCR test and the length of hospital stay were significantly longer for those aged five years or younger than others (P = 0.037, P = 0.01). Conclusion: Compared to adults, COVID-19 is milder and more distinctive in children. As a result, more conservative approaches might be preferred in children for the diagnostic, clinical, and even therapeutic applications.

Comparison of Safety Perception between Foreign and Local Workers in the Construction Industry in Republic of Korea

Korkmaz, Serdar,Park, Dal Jae Occupational Safety and Health Research Institute 2018 Safety and health at work Vol.9 No.1

Background: Since the Republic of Korea became a labor-force-importing country, the number of foreign workers has increased gradually, especially in the construction industry. The main objective of this study was to examine the differences in safety perception between domestic and foreign workers at Korean construction sites. Methods: A total of 891 Korean and foreign workers were surveyed: 140 foreign and 751 Korean workers. The general characteristics and 25 factors influencing safety perception were considered in the questionnaire. Regression and correlation analyses were conducted to examine the variables of workers' safety perception. Results: Differences of nationality (F = 7.379, p < 0.001) and workplace accidents were statistically significant for both domestic (F = 1.503, p < 0.05) and foreign workers (F = 7.868, p < 0.05). In contrast, age, education, and Korean language level were significant variables only for foreign workers. Correlation coefficients of $0.428^{**}$ for Korean and 0.148 for foreign workers between two items - namely, "management's commitment to safety" and "blaming staff when they make mistakes" - support the conclusion that foreign workers do not trust management's commitment to safety, while Korean workers have confidence in these commitments. Conclusion: Foreign workers' level of safety perception should rise to the same level as Korean workers, especially in terms of obeying safety rules, safety education performance, and safety beliefs. Therefore, an improvement plan for the Korean construction industry is suggested in order to have a better safety level at construction sites with foreign workers.

SIMULATION OF FREE SURFACE FLOW OVER TRAPEZOIDAL OBSTACLE WITH LATTICE BOLTZMANN METHOD

Emrah Korkmaz(코르크마츠 엠라),Rho-Taek Jung(정노택) 한국전산유체공학회 2014 한국전산유체공학회지 Vol.19 No.2

An air-water free surface flow simulation by using the Lattice Boltzmann Method(LBM) has not been studied a lot compared with the done by the Navier-Stoke equation. This paper shows the LBM is as one of the application tools for the free surface movement over an obstacle. The Mezo scaled application tool has been developed with two dimensional and nine discretized velocity direction using conventional lattice Bhatnagar-Gross-Krook model. Boundary conditions of a halfway-based for solid wall and a kinematic-based for interface are adopted. A validation case with a trapezoidal shape bump to make a comparison between freesurface movements from computational results and experimental ones was described with grid size dependency.

Could Sumac Be Effective on COVID-19 Treatment?

Hasan Korkmaz 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.6

Sumac is an herbal product, commonly consumed as a spice and was used for medical treatment for centuries. The phytochemical structure of Sumac was studied extensively, and it was established that the herb contained tannins, polyphenols, flavonoids, organic acids, and essential oils. Various scientific studies demonstrated that Sumac had a free oxygen radical-scavenging effect, a protective effect against liver damage, antihemolytic, leukopenia, and antifibrogenic effects, along with its antiviral, antimicrobial, anti-inflammatory, and antioxidant properties. Recently, several scientific studies described the pathophysiology, clinical course, and the treatment of COVID-19 infection. The examination of the characteristics of COVID-19 infection revealed via the clinical studies suggests that Sumac extract could be useful in the treatment of COVID-19. Given the scientific studies focusing on the beneficial effects of Sumac, the present review aims to provide an encouraging viewpoint to investigate whether Sumac is effective in treating COVID-19 infection.

A Curvature Property of Complex Contact Metric Structures

Belgin Korkmaz KYUNGPOOK UNIVERSITY 1998 Kyungpook mathematical journal Vol.38 No.1

.

한국어의 ‘-에, -에서’에 대응되는 터키어의 부사격조사 대조 연구

코르크마즈에므레 ( Korkmaz Muhammet Emre ),조은숙 ( Cho Eunsuk ) 연세대학교 언어정보연구원(구 연세대학교 언어정보개발원) 2018 언어사실과 관점 Vol.44 No.-

In this research, we have analyzed the errors of ‘-e’ and ‘-esoe’ of Turkish KFL learners and approached it in terms of comparative linguistics. Korean and Turkish have a commonality in that both languages are agglutinative languages due to Altaic systems. Therefore, there are affixes in Turkish which correspond to Korean adverbial cases. This fact can be very beneficial for acquiring the affixes of Korean language for Turkish learners in Turkey, but intrusive interference can be much more. In this paper, we applied a grammar and a translation test to Turkish KFL learners to examine whether intrusive interference occurs to Turkish L1 learners. As a result of the analysis, the error rate was high when using different usage for the same adverbial case. However, different usage for the same adverbial case may also result in lower rates of error and interference within the language. We listed the affixes of Turkish which corresponds to ‘-e’ and ‘-esoe’ in Korean, and hope to actively utilize in Korean language education such as teaching materials development and teaching methods.