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Synthesıs And Characterızatıon Of Au Nanopartıcle By Laser Ablatıon Technıque
No full textAltın nanoparçacıklar (Au NP ’ler), mükemmel biyouyumluluk, kimyasal stabilite ve teşvik edici optik özellikleri sebebiyle nanotıpdaki araştırma ve uygulamaların odak noktasıdır. Tez çalışmasının amacı, su veya polimer çözeltilerinde hazırlanan, lazerle sentezlenmiş Au NP ’lerin insan hücre dizilerindeki güvenilirlik, yükleme ve biyolojik davranışlarını karşılayacak üretim yapılmasıdır. Bu Au NP ’lerin üretimi, sıvı ortamda darbeli lazer ablasyon tekniği ile yapılmıştır. Lazer ablasyon işlemi, fiber lazer kullanan lazer nanoparçacık sentez sistemi (lazer ablasyon) ile yapılmıştır. Au NP numunelerinin saf deiyonize suda, küçük boyut dağılımına sahip olarak elde edilmesi için, lazer ablasyonu ile üretilen NP ’lere lazer parçalanma aşaması uygulanmıştır. Yüksek çözünürlüklü transmisyon elektron mikroskobu (TEM) ile mikroyapı, NP ’lerin UV / Vis spektrometresi ile optik absorbsiyon spektrumu ve NP ’lerin bir spektrofotometre kullanarak akış spektrumları elde edilmiştir. Elde edilen spektrum sonuçlarının literatür ile uygunluğu değerlendirilmiştirGold nanoparticles (Au NPs) are the focus of research and applications in nanomedicine because of their excellent biocompatibility, chemical stability and stimulating optical properties. The aim of the thesis is to produce the safety, loading and biological behavior of laser synthesized Au NPs prepared in water or polymer solutions in human cell lines. This production has been prepared for pulsed laser ablation technique in Au medium with Au NPs. Laser ablation was performed with laser nanoparticle synthesis system (laser ablation) using fiber laser. In order to obtain Au NP samples in pure deionized water with small size distribution, the laser fragmentation step was applied to the NPs produced by laser ablation. Microstructure were investigated by using high resolution transmission electron microscopy (TEM), optical absorption was examined using UV / Vis spectrometry of NPs and flow spectra of NPs were characterized by a spectrophotometer. The suitability of the obtained spectrum results with the literature was evaluate
Novel Coronavirus disease 2019 (COVID-19) in Newborns and Children [Yenidoǧanlarda ve Çocuklarda Yeni Koronavirus Hastaliǧi 2019 (COVID-19)]
No full textAnterior segment analysis and evaluation of corneal biomechanical properties in children with joint hypermobility
No full textA cross-sectional study in non-anaemic pregnant women in Turkey to assess necessity of iron supplementation [Étude transversale auprès de femmes enceintes non anémiques en Turquie pour évaluer la nécessité d'une supplémentation en fer]
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Investigation of Pseudomonas aeruginosa Biofilm Formation and Quorum Sensing Genes in Piperacillin/Tazobactam and Ciprofloxacin Sub-minimal Inhibitory Concentrations
No full textPseudomonas aeruginosa is a non-fermentative, oxidase-positive, motile
gram-negative bacillus widespread in nature. The virulence factors of
P.aeruginosa including the ability to grow under minimal growth
conditions, the widespread presence in nature, and the ability to form
biofilms make P.aeruginosa a highly important bacterium along with its
resistance mechanisms against many antibiotics. The ability to form
biofilms increases the symptom severity in diseases caused by
P.aeruginosa and causes difficulties in the treatment. The aim of this
study was to investigate the effects of sub-minimal inhibitory
concentrations (sub-MIC) of piperacillin/tazobactam (TZP) and
ciprofloxacin (CIP) which are used for the treatment of P.aeruginosa
infections on biofilm formation and to investigate the relationship
between the severity of biofilm formation and Quorum Sensing (QS) genes.
The study included 24 P.aeruginosa isolates from the culture collection
of Medical Microbiology Laboratory of Gazi University Faculty of
Medicine. MIC values of TZP and CIP antibiotics were determined by the
microdilution method. The biofilm layers in the antibiotic-free medium
and in the sub-MIC (MIC/2, MIC/4 ve MIC/8) concentrations of antibiotics
were visualized by using a scanning electron microscope (SEM). The QS
genes (lasl, lasR, rh/I, and MIR) of the 24 isolates with known biofilm
characteristics were identified via the amplification of chromosomal DNA
by using PCR method. In the study, it was foundthat both antibiotics
reduced biofilm formation in a dose-dependent manner in sub-MIC
concentrations compared to the antibiotic-free condition and that MIC/2
was the concentration, which reduced the biofilm formation most. These
results were further confirmed by viewing the SEM images. The QS genes
lasl, lasR, and Mil were detected in a total of 19 isolates with
moderately strong and strong biofilm formation, the rh/R gene was
detected in six of the strong biofilm-forming isolates, in four of the
moderately strong biofilm-forming isolates, and in three of the weak
biofilm-forming isolates, respectively. The investigation of the effects
of sub-MIC concentrations of antimicrobials, used for the treatment of
P.aeruginosa infections, on the biofilm formation of P.aeruginosa and
the investigation and better understanding of the QS systems associated
with biofilm production will allow for finding out new treatment
approaches and offer different options in combating infections with high
morbidity and mortality
An investigation into the relationship between willingness to communicate and classroom environment in a Turkish EFL context [İngilizce'yi yabancı dil olarak öğrenin Türk öğrencilerinin iletişim istekliliği ve sınıf iklimi algısı arasındasındaki ilişkinin incelenmesi]
No full textEFFECT OF STRAIGHT AND ANGLED ABUTMENTS ON THE STRAIN ON A ZIRCONIA CROWN AND IMPLANT IN THE MANDIBULAR SECOND MOLAR REGION: A FEA-BASED STUDY
No full textIn a literature search no study evaluating implant-supported posterior
restorations using zircon crowns with straight and angled abutments was
found. In this study, the stress distribution of a zircon-crown
restoration that will be prepared by using an angular and straight
abutment in a mandibular second-molar deficiency, under functional
forces, stress over zircon crown and environmental tissues of implant
will be evaluated using the finite-element analysis (FEA) method. The
FEA result showed that the use of straight implants contributes to the
lowest stresses. The selection of a straight and angular abutment is
very important for the balance of distributed loading
