Investigation of bar parameters occurred by cross-shore sediment transport

Demirci, Mustafa,Akoz, M. Sami The Society of Naval Architects of Korea 2013 International Journal of Naval Architecture and Oc Vol.5 No.2

Cross-shore sediment transport is very important factor in the design of coastal structures, and the beach profile is mainly affected by a number of parameters, such as wave height and period, beach slope, and the material properties of the bed. In this study cross-shore sediment movement was investigated using a physical model and various offshore bar geometric parameters were determined by the resultant erosion profile. The experiments on cross- shore sediment transport carried out in a laboratory wave channel for initial base slopes of 1/8, 1/10 and 1/15. Using the regular waves with different deep-water wave steepness generated by a pedal-type wave generator, the geometrical of sediment transport rate and considerable characteristics of beach profiles under storm conditions and bar parameters affecting on-off shore sediment transport are investigated for the beach materials with the medium diameter of $d_{50}$=0.25, 0.32, 0.45, 0.62 and 0.80 mm. Non-dimensional equations were obtained by using linear and non-linear regression methods through the experimental data and were compared with previously developed equations in the literature. The results have shown that the experimental data fitted well to the proposed equations with respect to the previously developed equations.

Investigation of bar parameters occurred by cross-shore sediment transport

Mustafa Demirci,M. Sami Aköz 대한조선학회 2013 International Journal of Naval Architecture and Oc Vol.5 No.2

Cross-shore sediment transport is very important factor in the design of coastal structures, and the beach profile is mainly affected by a number of parameters, such as wave height and period, beach slope, and the material properties of the bed. In this study cross-shore sediment movement was investigated using a physical model and various offshore bar geometric parameters were determined by the resultant erosion profile. The experiments on cross- shore sediment transport carried out in a laboratory wave channel for initial base slopes of 1/8, 1/10 and 1/15. Using the regular waves with different deep-water wave steepness generated by a pedal-type wave generator, the geometrical of sediment transport rate and considerable characteristics of beach profiles under storm conditions and bar parameters affecting on-off shore sediment transport are investigated for the beach materials with the medium diameter of d50=0.25,0.32, 0.45, 0.62 and 0.80 mm. Non-dimensional equations were obtained by using linear and non-linear regression methods through the experimental data and were compared with previously developed equations in the literature. The results have shown that the experimental data fitted well to the proposed equations with respect to the previously developed equations.

The Effect of Cross-Shore Sediment Transport on Bar Parameters: an Experimental Study

Demirci, Mustafa,Akoz, M. Sami Korean Society of Ocean Engineers 2012 International journal of ocean system engineering Vol.2 No.1

The cross-shore sediment transport in a coastal region causes the important changes in beach morphological properties. The accurate estimation of the cross-shore sediment transport is important for the designing of the marine structures such as seawalls, jetties, breakwaters etc, and the preventing coastal erosion and accretion due to on-off shore sediment transportation. In this study, the experiments on cross- shore sediment transport carried out in a laboratory wave channel for initial beach slopes of 1/8, 1/10 and 1/15. Using the regular waves with different deep-water wave steepness generated by a pedal-type wave generator, the geometrical characteristics of beach profiles under storm conditions and the parameters affecting on-off shore sediment transport are investigated for the beach materials having medium diameters of $d_{50}$=0.25, 0.32, 0.45, 0.62 and 0.80 mm. The experimental results obtained from this study compared with previous experimental work and found to be of the same magnitude as the experimental measurements and followed the expected basic trend.

Xanthan Gum Production under Different Operational Conditions by Xanthomonas axonopodis pv vesicatoria Isolated from Pepper Plant

Mustafa Mirik,Ahmet Sukru Demirci,Tuncay Gumus,Muhammet Arici 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.5

The influence of operational conditions (pH,stirrer speed, and temperature) used in the process of xanthan production by Xanthomonas axonopodis pv vesicatoria (XCVA3-1) isolated from pepper plant were evaluated through yield of xanthan and compared with control strain Xanthomonas campestris NRRL-B 1459. Different conditions used during the fermentation affected the xanthan production. In this study the best combination of yield was obtained, reaching 1.325 g/100 mL with the use of pH 7.0, 30^oC, and 250 rpm during fermentation. Increased yield of xanthan production can be obtained at high agitation values, with the maximum at 400 rpm. Higher yields of gum production can be obtained at 30^oC and the optimum pH was found 7.0. This results were similar for the X. campestris NRRL-B 1459.

Lymphoproliferative Disorders in Multiple Primary Cancers

Demirci, Umut,Ozdemir, Nuriye,Benekli, Mustafa,Babacan, Nalan Akgul,Cetin, Bulent,Baykara, Meltem,Coskun, Ugur,Zengin, Nurullah,Buyukberber, Suleyman Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Background: Cancer survivors are at increased risk of second cancers. Lymphoproliferative disorders (LPD) are common neoplasms that are primary or subsequent cancers in cases of multiple primary cancer. We here analyzed metachronous or synchronous LPD in multiple primary cancers. Methods: Between 2001 and 2010, LPD were assessed retrospectively in 242 multiple primary cancers patients. Results: Forty nine (20.2%) patients with LPD were detected. Six patients had two LPD where one patient had three LPD. The median age of patients was 60.5 years (range: 28-81). LPD were diagnosed in 29 patients as primary cancer, in 23 patients as second cancer, and in three patients as third cancer in multiple primary cancers. Primary tumor median age was 56 (range: 20-79). Diffuse large B cell lymphoma (n=16), breast cancer (n=9), and lung cancer (n=6) were detected as subsequent cancers. Alklylating agents were used in 19 patients (43.2%) and 20 patients (45.5%) had received radiotherapy for primary cancer treatment. The median follow-up was 70 months (range: 7-284). Second malignancies were detected after a median of 51 months (range: 7-278), and third malignancies with a median of 18 months (range: 6-72). Conclusions: In this study, although breast and lung cancer were the most frequent detected solid cancers in LPD survivors, diffuse large B cell lymphoma was the most frequent detected LPD in multiple primary cancers.

Docetaxel and Cisplatin in First Line Treatment of Patients with Unknown Primary Cancer: A Multicenter Study of the Anatolian Society of Medical Oncology

Demirci, Umut,Coskun, Ugur,Karaca, Halit,Dane, Faysal,Ozdemir, Nuriye Yildirim,Ulas, Arife,Baykara, Meltem,Benekli, Mustafa,Ozkan, Metin,Buyukberber, Suleyman Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.4

Background: The overall prognosis for cancers of unknown primary (CUP) is poor, median overall survival (OS) being 6-12 months. We evaluated our multicentric retrospective experience for CUP administered docetaxel and cisplatin combination therapy. Materials and Methods: A total of 29 patients that were pathologically confirmed subtypes of CUP were included in the study. The combination of docetaxel ($75mg/m^2$, day 1) and cisplatin ($75mg/m^2$, day 1) was performed as a first line regimen every 21 days. Results: The median age was 51 (range: 27-68). Some 17 patients had multimetastatic disease on the inital diagnosis. Histopathological diagnoses were well-moderate differentiated adenocarcinoma (51.7%), undifferentiated carcinoma (27.6%), squamous cell cancer (13.8%), mucoepidermoid carcinoma (3.4%) and neuroendocrine differentiated carcinoma (3.4%). Median number of cycles was 3 (range: 1-6). Objective response rate was 37.9% and clinical benefit was 58.6%. Median progression free survival (PFS) and overall survival (OS) were 6 months (range: 4.3-7.7 months) and 16 months (range: 8.1-30.9 months), respectively. Fourteen patients (60.8%) were treated in a second line setting. There was no treatment related death. Most common toxicities were nausia-vomiting (44.6%) and fatigue (34.7%), serious cases (grade 3/4) suffering nausia-vomiting (10.3%), neutropenia (13.8%) and febrile neutropenia (n=1). Conclusion: The combination of cisplatin and docetaxel is an effective regimen for selected patients with CUP.

Cytotoxic effects of different self-adhesive resin cements: Cell viability and induction of apoptosis

Sismanoglu, Soner,Demirci, Mustafa,Schweikl, Helmut,Ozen-Eroglu, Gunes,Cetin-Aktas, Esin,Kuruca, Serap,Tuncer, Safa,Tekce, Neslihan The Korean Academy of Prosthodonitics 2020 The Journal of Advanced Prosthodontics Vol.12 No.2

PURPOSE. The effects of four different self-adhesive resin cement materials on cell viability and apoptosis after direct and indirect exposure were evaluated using different cell culture techniques. MATERIALS AND METHODS. Self-adhesive cements were applied to NIH/3T3 mouse fibroblasts by the extract test method, cell culture inserts, and dentin barrier test method. After exposure periods of 24 h and 72 h, the cytotoxicity of these self-adhesive materials was evaluated using the MTT assay (viability) and the Annexin-V-FITC/PI staining (apoptosis). RESULTS. The lowest cell viability was found in cells exposed to BeautiCem SA for 24 h in the extract test method. Cell viability was reduced to 70.6% compared to negative controls. After the 72 h exposure period, viability rate of cell cultures exposed to BeautiCem SA decreased more than 2- fold (29.5%) while cells exposed to RelyX U200 showed the highest viability rate of 71.4%. In the dentin barrier test method, BeautiCem SA induced the highest number of cells in apoptosis after a 24 h exposure (4.1%). Panavia SA Cement Plus was the material that caused the lowest number of cells in apoptosis (1.5%). CONCLUSION. The used self-adhesive cements have showed different cytotoxic effects based on the evaluation method. As exposure time increased, the materials showed more cytotoxic and apoptotic effects. BeautiCem SA caused significantly more severe cytotoxic and apoptotic effects than other cements tested. Moreover, cements other than BeautiCem SA have caused necrotic cell death rather than apoptotic cell death.

Microhybrid versus nanofill composite in combination with a three step etch and rinse adhesive in occlusal cavities: five year results

Safa Tuncer,Mustafa Demirci,Evren Öztaş,Neslihan Tekçe,Ömer Uysal 대한치과보존학회 2017 Restorative Dentistry & Endodontics Vol.42 No.4

Objectives: The aim of the study was to evaluate the 5-year clinical performance of occlusal carious restorations using nanofill and microhybrid composites, in combination with 3-step etch-and-rinse adhesives, in patients who were going to commence orthodontic treatment. Materials and Methods: A total of 118 restorations for occlusal caries were conducted prior to orthodontic treatment. Occlusal restorations were performed both with Filtek Supreme XT (3M ESPE) and Filtek Z250 (3M ESPE) before beginning orthodontic treatment with fixed orthodontic bands. Restorations were clinically evaluated at baseline and at 1, 2, 3, 4, and 5-year recalls. Results: None of the microhybrid (Filtek Z250) and nanofill (Filtek Supreme XT) composite restorations was clinically unacceptable with respect to color match, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, or surface texture. A 100% success rate was recorded for both composite materials. There were no statistically significant differences in any of the clinical evaluation criteria between Filtek Z250 and Filtek Supreme XT restorations for each evaluation period. Conclusions: The composite restorations showed promising clinical results relating to color matching, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, and surface texture at the end of the 5-year evaluation period.

Microhybrid versus nanofill composite in combination with a three step etch and rinse adhesive in occlusal cavities: five year results

Tuncer, Safa,Demirci, Mustafa,Oztas, Evren,Tekce, Neslihan,Uysal, Omer The Korean Academy of Conservative Dentistry 2017 Restorative Dentistry & Endodontics Vol.42 No.4

Objectives: The aim of the study was to evaluate the 5-year clinical performance of occlusal carious restorations using nanofill and microhybrid composites, in combination with 3-step etch-and-rinse adhesives, in patients who were going to commence orthodontic treatment. Materials and Methods: A total of 118 restorations for occlusal caries were conducted prior to orthodontic treatment. Occlusal restorations were performed both with Filtek Supreme XT (3M ESPE) and Filtek Z250 (3M ESPE) before beginning orthodontic treatment with fixed orthodontic bands. Restorations were clinically evaluated at baseline and at 1, 2, 3, 4, and 5-year recalls. Results: None of the microhybrid (Filtek Z250) and nanofill (Filtek Supreme XT) composite restorations was clinically unacceptable with respect to color match, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, or surface texture. A 100% success rate was recorded for both composite materials. There were no statistically significant differences in any of the clinical evaluation criteria between Filtek Z250 and Filtek Supreme XT restorations for each evaluation period. Conclusions: The composite restorations showed promising clinical results relating to color matching, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, and surface texture at the end of the 5-year evaluation period.

The effect of sandblasting duration on the bond durability of dual-cure adhesive cement to CAD/CAM resin restoratives

Neslihan Tekçe,Safa Tuncer,Mustafa Demirci 대한치과보철학회 2018 The Journal of Advanced Prosthodontics Vol.10 No.3

PURPOSE. To evaluate the effect of prolonged sandblasting on the bond durability of dual-cure adhesive resin cement to computer-aided design and computer-aided manufacturing (CAD/CAM) restoratives. MATERIALS AND METHODS. Nano-ceramic LAVA Ultimate and hybrid-ceramic VITA Enamic CAD/CAM blocks were used for this study. Each CAD/CAM block was sectioned into slabs of 4-mm thickness for the microtensile test (μTBS) test and 2-mm thickness for the surface roughness test. Three groups were created according to the sandblasting protocols; group 1: specimens were sandblasted for 15 seconds, group 2: specimens were sandblasted for 30 seconds, and group 3: specimens were sandblasted for 60 seconds. After sandblasting, all specimens were luted using RelyX Ultimate Clicker. Half the specimens were subjected to μTBS tests at 24 hours, and the other half were subjected to tests after 5000 thermocycles. Additionally, a total of 96 CAD/CAM block sections were prepared for surface roughness tests and scanning electron microscopy (SEM) evaluations. The Mann-Whitney U test, Kruskal-Wallis one-way analysis of variance, and Dunn’s post hoc test were used to compare continuous variables among the groups. RESULTS. At baseline, group 1, group 2, and group 3 exhibited statistically similar μTBS results for LAVA. However, group 3 had significantly lower μTBS values than groups 1 and 2 for VITA. After 5000 thermocycles, μTBS values significantly decreased for each block (P<.05). CONCLUSION. It is important to perform controlled sandblasting because it may affect bond strength results. Sixty seconds of sandblasting disturbs the initial μTBS values and the stability of adhesion of CAD/CAM restoratives to dual-cure adhesive resincement for VITA Enamic.