TR Dizin İndeksli Yayınlar Koleksiyonu / TR Dizin Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14365/4
Browse
51 results
Search Results
Article İnfluenza A/B Virüs ve RSV Validasyon Standartlarının Dijital PCR ile Kantitasyonu(Ankara Microbiology Soc, 2025-07-26) Sayıner, Ayca Arzu; Bulgurcu, AlıhanMikrobiyolojik tanı laboratuvarlarında kullanılacak tanı testleri için kantitatif standartların kullanıldığı yöntem doğrulama (verification) veya geçerli kılma (validation) çalışmaları gereklidir. Nükleik asit testlerinde sentetik nükleik asit veya plazmit yerine tam virüs içeren standartların kullanılması; ekstraksiyon, revers transkripsiyon ve amplifikasyonu içerecek şekilde tanı testinin tüm basamaklarının gerçek yaşam koşullarında değerlendirilmesini sağlar. Solunum yolu virüsleri için nükleik asit testlerine yönelik ticari kantitatif standart materyaller sınırlıdır. Bu çalışmada; influenza A virüs (infA), influenza B virüs (infB) ve respiratuvar sinsityal virüs (RSV) için dijital polimeraz zincir reaksiyonu [digital polymerase chain reaction (dPCR)] kullanılarak, kantitatif nükleik asit standartları geliştirilmesi amaçlanmıştır. Çalışmada; RSV, infA, infB RNA pozitif olduğu bilinen nazofarengeal sürüntü örneklerinin havuzlanmasıyla hazırlanan örneklerdeki viral nükleik asit miktarı, ticari primer/prob setleri (Qiagen, Almanya) kullanılarak dPCR (QIAcuity, Qiagen) yöntemiyle belirlenmiştir. Nükleik asit ekstraksiyonu, ticari bir kit (Xi’an Tianlong Science&Technology Co, Çin) kullanılarak yapılmıştır. dPCR yönteminin infA, infB ve RSV için analitik duyarlılık (LoD) ve kantitasyon alt sınırı (LoQ), çalışma içi ve çalışmalar arası tekrarlanabilirliği ve doğrusallığı belirlenmiştir. dPCR ile çalışılan örnekler, kantitatif revers transkripsiyon gerçek zamanlı [quantitative reverse transcription realtime (qrRT)] PCR (qRT-PCR) ile de çalışılarak Ct değerleri belirlenmiştir. Ct değerleri ile dPCR-kantitasyon sonuçları arasındaki ilişki lineer regresyon ile değerlendirilmiştir. İstatistiksel analiz GraphPad Prism 10.4.0 (GraphPad, ABD) ve Excel Analysis ToolPak kullanılarak yapılmıştır. İnfA, infB ve RSV için dPCR yönteminin LoD değerleri sırasıyla 93.75, 15.59 ve 26.23 kopya/mL olarak belirlenmiştir. dPCR yönteminin çalışma içi tekrarlanabilirliği (varyasyon katsayısı, %CV), düşük viral yükü olan örneklerde daha yüksek olmak üzere 0.06-7.97 arası saptanmıştır. Çalışmalar arası tekrarlanabilirlik 0.73-5.41 olarak bulunmuştur. İnfA ve infB için 3-4 log10, RSV için 7 log10 aralığında dilüsyonlar ile yapılan doğrusallık analizinde her üç virüs için de r 2≥ 0.99 olarak bulunmuştur. dPCR ile ölçülen konsantrasyonların, qRT-PCR Ct sonuçları ile korele olduğu saptanmıştır. dPCR ile qRT-PCR testlerinin çalışma içi ve çalışmalar arası tekrarlanabilirlik sonuçları karşılaştırıldığında, dPCR’nin %CV değerinin anlamlı olarak daha düşük olduğu saptanmıştır (p= 0.0312). Çalışma sonuçları dPCR yönteminin, kantitatif nükleik asit standartları elde etmede tekrarlanabilirliği yüksek ve güvenilir bir yöntem olduğunu göstermiştir. Elde edilen kantitatif standartlar ile viral yük belirlemeye yönelik tanı yöntemleri geliştirmek ve/veya bu tür testlerin yöntem onayı analizlerini yapmak mümkündür. Sonuç olarak çalışmada, havuzlanmış hasta örnekleri kullanılarak dPCR yöntemiyle infA, infB ve RSV için güvenilir kantitatif nükleik asit standartlar elde edilmiş ve dPCR yönteminin performans analizleri gerçekleştirilmiştir. Bu çalışma, dPCR ile kantitatif viral nükleik asit standartlarının üretimine bir örnek olmuştur.Article Investigation of Glass Ceiling Syndrome Among Radiation Professionals: a Comparative Analysis(Dokuz Eylul Univ inst Health Sciences, 2025-05-31) Şişman, Gizem; Çilengiroğlu, Özgül Vupa; Alkan, TurkanBackground and Purpose: This study investigates the perception of the glass ceiling syndrome among radiology, nuclear medicine, and radiation oncology technicians in healthcare institutions in Turkey. Methods: A comparative approach was used to examine the prevalence and impact of the glass ceiling on female workers. Data was collected via questionnaires from 311 participants in Turkey, and analyzed using descriptive statistics, chi-square analysis, and independent sample tests. Results: The results indicate that 78.1% of the participants were women, 64% were medical imaging technicians and 65.3% were employed in private institutions. A significant difference was found in the total and subscale scores of the glass ceiling scale (excluding mentoring) based on gender (p<0.05). Conclusion: This study enhances understanding of gender dynamics among radiation workers and highlights the need for targeted interventions to address the glass ceiling syndrome. The findings provide key insights for promoting workforce equity and organizational development in healthcare institutions.Article Second Order Latent Growth Models and Measurement Equivalence(Turkish Education Assoc, 2011) Dural, Seda; Somer, Oya; Korkmaz, Mediha; Can, Seda; Ogretmen, Tuncay; Çetinkaya, Seda DuralResearch problems related to individuals' behaviors and attitudes requires examining inevitable changes over time. Because learning by nature implies change, analysis of longitudinal data becomes an important topic especially in the field of education. In this article, linear changes of a particular attribute over time was studied in the framework of the second order latent growth models by using data generated from Monte Carlo simulation. All analyses were performed by using Mplus 5.1 software. Related Mplus syntaxes were introduced and the interpretation of the model parameters was discussed. Additionally, it was explained how to study measurement equivalence in these models. Analyses were performed in three steps: (1) basic latent growth model, (2) latent growth model with weak measurement equivalence, and (3) strong measurement equivalence.Article Impacts of Augmented Reality Marketing on Gen-Z Fashion Consumers Behavioral Intention(Chamber of Textile Engineers, 2024-12-31) Günduru, Beliz; Deniz, DenizYenilikçi teknolojiler tekstil ve moda endüstrisi için büyük önem arz etmektedir. Bu bağlamda bu araştırma çalışması, belirli bir artırılmış gerçeklik (AR) uygulamasını kullanarak AR teknolojilerinin Z Kuşağı moda tüketicilerinin davranışsal niyetleri üzerindeki etkisini anlamayı amaçlamaktadır. Bu çalışma, araştırma verilerini toplamak amacıyla 5 puanlık Likert Ölçeği ile modifiye edilmiş olan UTAUT2 modeline dayalı bir anket kullanılmıştır. Anket, yedi yapı altında dağıtılmış yirmi üç sorudan oluşmaktadır. 310 erkek ve kadın Z Kuşağı tüketicisi örneklem kullanılarak yapılan bulgular, algılanan değer (PV) boyutunun, Z Kuşağı tüketicilerinin moda alışverişi için AR teknolojisini kullanma niyetlerini olumlu yönde etkilediğini göstermektedir. Bulgular, araştırma modelinin davranışsal niyetin %75'ini açıkladığını ortaya koymaktadır. Tüm araştırma sonuçlarıyla, teknoloji kabul ve kullanım birleştirilmiş modeli-2 (UTAUT2) altı boyutu ile doğrulanmıştır. UTAUT2 modeline eklenen algılanan değer (PV) boyutu, modeli iyileştirmiştir. Orijinallik açısından, bu araştırma çalışması, gelişmiş bir AR uygulaması aracılığıyla belirli bir kullanıcı grubu olan Z Kuşağı moda tüketicilerinin davranışsal niyetleri üzerindeki artırılmış gerçeklik teknolojisinin etkilerini tanımlamaktadır.Article Upregulated Acute Systemic Inflammation-Related Genes Based on Endotoxin Exposure Provide ‘Survival Benefit’ or Create ‘High Risk of Death’ in Leukaemia and Colon Cancer(Istanbul University, 2024-07-10) Duran, Gizem Ayna; Duran, Assist. Prof. Dr. Gizem Ayna; Ayna Duran, GizemObjective: Although endotoxin exposure has been shown to trigger innate immune responses and promote cancer, it has also been shown to prevent cancer formation. In our study, survival analysis was performed to determine whether the upregulated genes triggered by endotoxins have hazardous effects on cancers or provide a survival benefit. Materials and Methods: Gene intensity values of control and bacterial endotoxin-administered individuals were obtained from the Gene Expression Omnibus database. Using the R "Linear Models for Microarray Data" package, differentially expressed gene analyses were conducted to determine genes that differ between healthy and bacterial endotoxin-administered samples. "ShinyGo 0.80" web-based tool was used to determine the disease types indicated by these genes. The "Kaplan-Meier Plotter" web-based tool was used to conduct survival analysis. Results: Genes that create an innate immune response to bacterial endotoxin exposure and are upregulated differently than in individuals without exposure were identified. According to gene enrichment analyses, the two main types of cancer identified were leukaemia/lymoma and colon cancer. We detected that MLF1, STAT5B, and BCL3 genes led to poor survival; however, the ARHGAP26 gene was protective for acute myeloid leukaemia patients. In the case of colon cancer, SMAD7 and TLR2 genes were determined as leading to "high risk of death". Conclusion: Once the systemic inflammation-related genes identified in our study are confirmed through laboratory experiments in samples taken from solid tissue in the case of colon cancer and at the level of genes obtained from blood samples in leukemias, genetically targeted treatments will also be possible.Article Citation - Scopus: 2A Bibliometric Analysis of Publications on Emergency Medicine in Turkiye(Wolters Kluwer Medknow Publications, 2024-07) Guzelce, Mustafa Can; Orhan, Ertug; Ozgur, SeferOBJECTIVES: Publications and literature related to emergency medicine (EM) have been consistently increasing. There are 4048 studies in total in the EM journals published until the present day in Turkiye in the Web of Science (WoS) database. Our aim is to define the bibliometric features of scientific studies published in EM journals in Turkiye, to gain insights into the trends of the literature. METHODS: We retrospectively analyzed the bibliometric data of scientific studies published in EM journals in Turkiye until today on the WoS database related to the EM field. The bibliometrix package of R statistical software was used in the bibliometric analyses in the study. RESULTS: A total of 4048 scientific studies from Turkiye indexed on the WoS database from 10,263 authors in four different journals were analyzed. Among these, 3681 (90.9%) were articles, 188 (4.7%) were reviews, 97 (2.4%) were editorial material, 60 (1.5%) were letters, and 5 (0.1%) were corrections. Average number of citations per study was 3.6, with the most cited study having 2016 citations. The most frequent title's words were emergency, patient, and acute. CONCLUSION: This study shows that there is an increasing trend in the number of EM publications and citations in Turkiye with the first most cited study having 2016 citations, and the top contributing countries were Turkiye, Iran, and India. The results of this study may be useful in understanding the historical and prospective development of EM, including the identification of general information about its publications, differentiation of the top-cited ones, and presentation of a bibliometric analysis of scientific activity to date.Article When Are You Going To Marry? Intention To Marry Through the Lens of Theory of Planned Behavior and Self-Regulatory Focus(Turkish Psychological Counseling and Guidance Association, 2024-03-29) Koçak, Aylin; Mouratidis, A.What makes people to take important decisions in their lives, such as marriage? To answer this question, we relied on theory of planned behavior to examine the degree to which peoples' attitudes, subjective-norms, and behavioral control perceptions predict their intentions to marry. Furthermore, we used self-regulatory focus theory to examine whether such attitudes, norms, and perceptions could be partly explained by peoples' focus on pursuing-gains versus securing non-losses. We conducted a cross-sectional, web-based survey with a sample of 699 Turkish young adults (70.7% females; Mage =24.89 years, SD = 4.31). The results of the structural equation modeling showed that promotion-focus positively and prevention-focus negatively related to perceived behavioral control, which in turn negatively related to intentions to marry. Intentions also related positively to attitudes but not to subjective-norms, which however related positively to promotion-focus and negatively to prevention-focus. Gender and age differences were also found. The results are discussed in light of the two theories. © 2024 The Authors. Turkish Journal of Counseling Psychology and Guidance is published by Turkish Psychological Counselling and Guidance Association.Article Citation - WoS: 5Citation - Scopus: 7Detection of Olfactory Stimulus in Electroencephalogram Signals Using Machine and Deep Learning Methods(Istanbul University, 2024-01-30) Akbuğday, Burak; Akbugday, S.P.; Sadikzade, R.; Akan, A.; Unal, S.; Sadighzadeh, RezaThe investigation of olfactory stimuli has become more prominent in the context of neuromarketing research over the last couple of years. Although a few studies suggest that olfactory stimuli are linked with consumer behavior and can be observed in various ways, such as via electroencephalogram (EEG), a universal method for the detection of olfactory stimuli has not been established yet. In this study, 14-channel EEG signals acquired from participants while they were presented with 2 identical boxes, scented and unscented, were processed to extract several linear and nonlinear features. Two approaches are presented for the classification of scented and unscented cases: i) using machine learning (ML) methods utilizing extracted features; ii) using deep learning (DL) methods utilizing relative sub-band power topographic heat map images. Experimental results suggest that the olfactory stimulus can be successfully detected with up to 92% accuracy by the proposed method. Furthermore, it is shown that topographic heat maps can accurately depict the response of the brain to olfactory stimuli. © 2024 Istanbul University. All rights reserved.Article Fluorescence Microscopy Denoizing Via Neighbor Linear Embedding(Istanbul University, 2024-01-31) Kırmızıay, Çağatay; Aydeniz, Burhan; Türkan, MehmetOne of the difficulties in studying fluorescence imaging of biological structures is the presence of noise corruption. Even though hardware- and software-related technologies have undergone continual improvement, the unavoidable effect of Poisson–Gaussian mixture type is generally encountered in fluorescence microscopy images. This noise should be mitigated to allow the extraction of valuable information from fluorescence images for various types of biological analysis. Thus, this study introduces a new and efficient learning-based denoizing approach for fluorescence microscopy. The proposed approach is based mainly on linear transformations between noise-free and noisy submanifold structures of patch spaces, benefiting from linear neighbor embeddings of local image patches. According to visual and statistical results, the developed algorithm called "neighbor linear-embedding denoizing" algorithm has a highly competitive and generally superior performance in comparison with the other algorithms used for fluorescence microscopy image denoizing in the literature. © 2024 Istanbul University. All rights reserved.Article Citation - WoS: 1Life Cycle Assessment of Tomato Paste Production: a Case Study(Pamukkale Unıv, 2024) Üçtuğ, Fehmi Görkem; Tekin, Zehranur; Dayıoglugil, Zeynep; Ulusoy, Ercan; Oktaylar Keyik, Şule; Keyik, Sule OktaylarThis study involves the cradle -to -gate life cycle assessment of tomato paste production in Turkey. All the data was obtained from a large-scale production company located in north-west Turkey in 2020. CCaLC software with Ecoinvent2 database alongside CML2001 method was used for the analysis and the following impacts were taken into account: acidification potential, carbon footprint, eutrophication potential, human toxicity potential, ozone layer depletion potential, and photochemical smog potential. Functional unit was chosen as 1 kg of tomato paste sold in glass jars. The results show that the biggest contributor to environmental impacts was the raw material supply stage, mainly due to fungicide (for agriculture) and metal (for packaging) use. Energy required for agricultural and production processes were also found to have significant effects of the impacts. The results were found to be in very good consistency with earlier literature. Using photovoltaic panels for meeting 10% of the electricity demand of agricultural and production processes or utilizing tomato harvesting waste to produce biomethane were found to have almost no positive effects as far as impact reduction is concerned. These results show that switching to organic farming seems to be essential if environmental impacts of processed food products such as tomato paste are to be reduced.