Dentin hassasiyet giderici ajanların tek aşamalı bir self-etch adezivin makaslama bağlanma dayanımına etkisi

Amaç: Bu çalışmanın amacı içerikleri farklı 12 adet dentin hassasiyet giderici ajanın (DHGA) bir self-etch adeziv rezinin makaslama bağlanma dayanımına etkisinin belirlenmesidir. Gereç ve Yöntem: Bu çalışmada kullanılmak üzere 195 adet çürüksüz daimi alt 3. molar dişin bukkal yüzeyindeki dentin dokusu açığa çıkacak şekilde mine dokusu uzaklaştırıldı. Dentin örnekleri rastgele 13 gruba ayrıldı (n=15). On iki farklı DHGA (Smart Protect, Systemp Desensitizer, Seal&Protect, Aqua-Prep F, Isodan, Gluma, BisBlock, D/Sense Crystal, UltraEZ, Colgate Sensitive Pro-  Relief, Topex ve Clinpro White Varnish) uygulama talimatlarına göre dentin yüzeylerine uygulandı. Kontrol grubuna DHGA uygulanmadı. Dentin örnekleri 14 gün boyunca 37°C’de yapay tükrük içinde bekletildi. Sonra yumuşak bir diş fırçası yardımıyla dentin yüzeyindeki kalıntılar 8-10 kez uygulanan dairesel hareketlerle uzaklaştırıldı. Clearfil Tri-S Bond (Kuraray Medical) dentin yüzeylerine uygulandıktan sonra silindirik kalıplar yardımıyla kompozit rezin (Filtek Z 250, 3M ESPE, USA) dentin yüzeyine uygulandı. Hazırlanan örnekler 24 saat boyunca distile suda, 37 ºC’de, etüvde bekletildi. Makaslama bağlanma dayanımının ölçüm testleri Universal Çekme-Basma Test Sistemi (Instron 3382, USA) kullanılarak yapıldı. Her bir grup için 3 adet dentin örneği hazırlanarak DHGA’nın dentin tübül tıkaç etkinliği SEM ile incelendi. Gruplar arasında bağlanma dayanımı yönünden farkın önemliliği Tek Yönlü Varyans Analizi (One-Way ANOVA) ve post hoc Tukey testi kullanılarak tespit edildi. p0.05). Sonuçlar: Bu in vitro çalışmada fluorür ve potasyum okzalat içeren DHGA uygulamaları tek aşamalı bir self-etch adezivin rezin-dentin makaslama bağlanma dayanım değerinde azalmaya neden olmuştur. Bunun muhtemel nedeni SEM incelemelerinde görüntülendiği gibi bu ajanların oluşturduğu dentin tübül tıkaçlarının, zayıf asiditesi olan self-etch adezivin dentin tübüllerine penetrasyonunu engellemesi olabilir

Planktonic foraminiferal, calcareous nannoplankton biostratigraphy, ostracod assemblage and paleoenvironmental interpretation of the Eocene Seydiler formation (Kastamonu, NW Turkey)

Bu çalışmada; Kastamonu ili kuzeyinde, Şeydiler ve Ağlı ilçeleri ile İmranlar köyü arasında yüzeylenen Seydiler formasyonundan derlenen örneklerden Bartoniyen-Priaboniyen zaman aralığını temsil eden Truncoro-taloides rohri, Globigerinatheka semiinvoluta ve Turborotalia cerroazulensis s.l. planktonik foraminifer zonları ile Reticulofenestra umbilica ve Discoaster barbadiensis kalkerli nannoplankton zonları tanımlanmıştır. Örneklerdeki planktonik/bentonik foraminifer oranlarının dağılımları ve ostrakod toplulukları birlikte değerlendirildiğinde, inceleme alanında Bartoniyen-Priaboniyen zaman aralığında yöredeki denizin genel olarak önce transgresif, Priaboniyen sonunda ise regresif karakterde olduğu belirlenmiştir. Isıya karşı duyarlı kalkerli nannoplankton türlerinin bolluk dağılımları (%) değerlendirildiğinde, Bartoniyen-Priaboniyen zaman aralığında yörede deniz yüzey suyunun genel olarak ılıman-sıcak karakterde olduğu, bazı seviyelerde zaman zaman ılıman-serin ve ılıman-sıcak fazların birbirlerini izledikleri, dolayısıyla bu dönemde yörede zaman zaman soğuk su akıntılarının etkin olduğu belirlenmiştir.In this, study, Truncorotaloides rohri, Globigerinatheka semiinvoluta and Turborotalia cerroazulensis s.l. planktonic foraminiferal zones and Reticulofenestra umbilica and Discoaster barbadiensis calcareous nannoplankton zones, indicating Bartonian-Priabonian interval, were recognized in the samples from the Seydiler formation located between Seydiler and Ağlı towns and İmranlar village at the north of Kastamonu city. According to distribution of the planktonic/benthonic foraminiferal ratio (%) and ostracod assemblage in the samples of the formation, it was determined that the sea was generaly in transgressive character during the Bartonian-Priabonian interval, after that it was in regressive character during the Late Priabonian time in the studied area. Moreover, abundance percentage and diversity of temperature-sensitive calcareous nannoplankton groups indicate that the sea-surface water in the study area had a tropical-temperate character in the Bartonian-Priabonian time interval. In addition, it was determined that tropical-temperate and temperate-cool phases have been occasionally prevailed on the sea and this was only related with cool-water currents at the some intervals in the Priabonian time

Eosen yafll› Seydiler formasyonunun (Kastamonu, KB Türkiye) planktonik foraminifer, kalkerli nannoplankton biyostratigrafisi, ostrakod topluluğu ve eski ortam yorumu

Yıldız, Ayşegül ( Aksaray, Yazar )In this study, Truncorotaloides rohri, Globigerinatheka semiinvoluta and Turborotalia cerroazulensis s.l. planktonic foraminiferal zones and Reticulofenestra umbilica and Discoaster barbadiensis calcareous nannoplankton zones, indicating Bartonian-Priabonian interval, were recognized in the samples from the Seydiler formation located between Seydiler and Aǧli towns and Imranlar village at the north of Kastamonu city. According to distribution of the planktonic/benthonic foraminiferal ratio (%) and ostracod assemblage in the samples of the formation, it was determined that the sea was generaly in transgressive character during the Bartonian-Priabonian interval, after that it was in regressive character during the Late Priabonian time in the studied area. Moreover, abundance percentage and diversity of temperature-sensitive calcareous nannoplankton groups indicate that the sea-surface water in the study area had a tropical-temperate character in the Bartonian-Priabonian time interval. In addition, it was determined that tropical-temperate and temperate-cool phases have been occasionally prevailed on the sea and this was only related with cool-water currents at the some intervals in the Priabonian time

Planktonic foraminiferal, calcareous nannoplankton biostratigraphy, ostracod assemblage and paleoenvironmental interpretation of the Eocene Seydiler formation (Kastamonu, NW Turkey) [Eosen yaşli Seydiler formasyonunun (Kastamonu, KB Türkiye) planktonik foraminifer, kalkerli nannoplankton biyostratigrafisi, ostrakod toplulugu ve eskiortam yorumu]

In this study, Truncorotaloides rohri, Globigerinatheka semiinvoluta and Turborotalia cerroazulensis s.l. planktonic foraminiferal zones and Reticulofenestra umbilica and Discoaster barbadiensis calcareous nannoplankton zones, indicating Bartonian-Priabonian interval, were recognized in the samples from the Seydiler formation located between Seydiler and Agli towns and Imranlar village at the north of Kastamonu city. According to distribution of the planktonic/benthonic foraminiferal ratio (%) and ostracod assemblage in the samples of the formation, it was determined that the sea was generaly in transgressive character during the Bartonian-Priabonian interval, after that it was in regressive character during the Late Priabonian time in the studied area. Moreover, abundance percentage and diversity of temperature-sensitive calcareous nannoplankton groups indicate that the sea-surface water in the study area had a tropical-temperate character in the Bartonian-Priabonian time interval. In addition, it was determined that tropical-temperate and temperate-cool phases have been occasionally prevailed on the sea and this was only related with cool-water currents at the some intervals in the Priabonian time

Biodiesel production from hempseed (Cannabis sativa L.) oil: Providing optimum conditions by response surface methodology

This study focuses on the optimization of biodiesel synthesis using non-edible hempseed oil as the feedstock. The response surface method was used to find the best methanol: oil molar ratio, catalyst concentration, reaction temperature, and reaction duration for the transesterification process. The center composite design experimental design was used to make the design. A total of 30 cycles were conducted to adjust the four parameters at five different levels in order to optimize the biodiesel production process. It was found that the best conditions for transesterification of hempseed oil were a KOH catalyst concentration of 0.80 wt.%, a molar ratio of 7.41:1, a reaction time of 62.83 min, and a reaction temperature of 61.92 °C. Under these optimized reaction conditions, the predicted biodiesel yield was 95.57%, while the experimental yield was 95.24%. The biodiesel produced using the optimized parameters was analyzed for its properties, and the findings demonstrated that it met the requirements of EN 14214, a standard for biodiesel quality. The optimization of the biodiesel synthesis process using non-edible hempseed oil contributes to the exploration of alternative and sustainable feedstocks for biodiesel production. The values of the produced biodiesel within the standard range demonstrate its suitability for commercial applications and strengthen the potential of hemp seed oil as a suitable raw material for biodiesel production

Bond Strength of Calcium Silicate-Based Sealers to Dentine Dried with Different Techniques

Objective To assess the influence of various canal-drying techniques on the push-out bond strength between radicular dentine and both MTA Fillapex and iRoot SP sealers. Materials and Methods Eighty extracted single-root teeth were instrumented with ProTaper Universal rotary instruments to a size F4. The teeth were randomly assigned to 1 of 4 groups as follows: group 1, excess fluid in the canals was removed using a Luer vacuum adapter; group 2, the canals were dried with a single paper point; group 3, the canals were dried with 3–5 paper points, and group 4, the canals were rinsed with 95% ethanol and then dried with 3–5 paper points. In each group, the specimens were subgrouped according to root canal sealer into either subgroup A (MTA Fillapex) or subgroup B (iRoot SP sealer). Horizontal sections (thickness 1 ± 0.1 mm) were obtained from each specimen and a push-out test was performed using a universal testing machine at a crosshead speed of 1 mm/min on root slices. Statistical analysis was done using the Kruskal-Wallis test and Dunn's test for pair-wise comparisons. p 0.05). Conclusions The canal-drying technique influenced the adhesive bond strength between calcium silicate-based root canal sealers and the root canal wall.PubMedWoSScopu

The aspects of the Late Quaternary (Holocene) setting belong to the eastern Gulf of Izmit, Adapazari, the delta of Sakarya and their environments ̇Izmit Körfezi'nin doǧusu, Adapazari, Sakarya Deltasi ve çevreleri Geç Kuvaterner (Holosen) çökellerinin özellikleri

This study is carried out on the settings of Holocene at eastern Gulf of ̇Izmit, Adapazari, Sakarya Delta and its vicinity, and based on 86 samples collected from the boreholes. The pollen diagram, based on the data from the boreholes drilled at Adapazari and its vicinity, suggested that high herbaceous pollen percentages of particularly Chenopodiaceae and Compositae, and Pinus and Quercus were present during the Early Holocene (approximately 11.300 BP years). Absent of the foraminifers in deltaik environment indicates that there was no any sea effect on the delta. In addition, the Gulf of Izmit, which was connected to Sakarya River in the Middle Pleistocene, moved to west. Moreover, when the elevations of the boreholes and different numerical ages (11.000-3.780 BP years) assigned at different depths are considered, it can be concluded that the region was under the control of tectonic activities in the forms of subsidence and uplift