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Preparation, characterization, and antimicrobial activities of ceragenins incorporated into polyvinyl alcohol/gelatin/sodium alginate-based hydrogels for treatment of burn wounds
No full textCeragenins are synthetic molecules that mimic antimicrobial peptides (AMPs) in the human immune system. They feature a bile acid-based structure with appended positively charged groups that disrupt bacterial cell membranes, leading to microbial cell death or inactivation. In this study, ceragenin CSA-44 was incorporated into a polyvinyl alcohol (PVA)/gelatin (G)/sodium alginate (SA)-based hydrogel (PGA-CSA). The hydrogel was cross-linked with glutaraldehyde (GA) for 20 min using a 0.125% GA (v/v) solution. The optimized volume ratios of the polymer solutions in the hydrogel were determined to be 2:1:3 (PVA:SA:G). PGA-CSA and PGA hydrogels were characterized using scanning electron microscopy (SEM), mercury porosimetry, and Fourier transform infrared spectroscopy (FTIR). The maximum swelling ratio of PGA-CSA was 780.48% +/- 14.80%, and the WVTR value was 905.4 +/- 35.4 g/m2/d. Drug release studies showed a cumulative CSA-44 release of 29.07% over 7 days. The antibacterial activity of the hydrogel was tested against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 19151, Staphylococcus aureus ATCC 29213, and MRSA. The tested bacteria were inhibited within 2, 2.5, 3, and 3.5 h, respectively. The developed PGA-CSA hydrogel demonstrated outstanding potential and unique characteristics as an antibacterial dressing for burn wounds
Zeugma’daki Poseidon Villası emblemasında betimlenen Eros ve sözde “Psykhe”
No full textThe aim of this research is an iconographical and iconological analysis focused on the emblema with Eros and so-called “Psyche” from the Poseidon Villa at Zeugma. At a methodological level the mosaic has been duly contextualised in relation to the house and the site of origin, considering the other mosaics from the Poseidon Villa. For this purpose mosaics and other finds were analysed from both the eastern (Syria, Egypt) and western parts of the Roman Empire (Italy) passing through Greece. A new identification of the female figure (Psyche or Telete?) in the emblema from the Poseidon Villa was proposed. The Dionysiac context of the scene (Eros-Dionysus adolescent) was related to the presence of Dionysus in other mosaic panels from the house, highlighting the nuptial character of this representation and the role of Dionysus regarding the marriage rites (Cfr. the Dionysiac frieze of the Villa of the Mysteries at Pompeii and the Aldobandrini Wedding). In this perspective the identification of the so-called “Psyche” with a bride belonging to the human sphere has been proposed. But it is a human sphere that interacts closely with the divine one. The human bride next to Eros has a clothing, posture and attitude that is both modest and seductive, so as to evoke the famous Aphrodite Sosandra. This statuary type must have been well known in the eastern part of the Roman Empire, especially at Zeugma, as documented through the circulation of several copies, in the second half of the 2nd century AD. We suggest that the dominus-client perhaps must have been a Roman high-ranking army officer, belonging to the IV Legio Scythica and resident in a cosmopolitan context.Bu araştırmanın amacı, Zeugma’daki Poseidon Villası’ndan Eros ve sözde “Psykhe” tasvirli emblema üzerine ikonografik ve ikonolojik bir analiz yapmaktır. Metodolojik olarak mozaik, hem ev hem de bulunduğu yerle ilişkilendirilerek kontekste oturtulmuş, Poseidon Villası’ndaki diğer mozaikler de dikkate alınmıştır. Bu amaçla hem Roma İmparatorluğu’nun doğu bölgelerinden (Suriye, Mısır) hem de batı bölgelerinden (İtalya), ayrıca Yunanistan’dan mozaikler ve diğer buluntular analiz edilmiştir. Poseidon Villası’ndaki emblema üzerindeki kadın figürünün (Psykhe mi yoksa Telete mi?) yeni bir şekilde tanımlanması önerilmiştir. Sahnedeki Dionysos betimi (ergen Eros-Dionysos) evdeki diğer mozaik panolarda Dionysos’un varlığıyla ilişkilendirilmiş, bu temsilin evlilik karakterine ve Dionysos’un evlilik ritüellerindeki rolüne dikkat çekilmiştir (Pompeii’deki Gizemler Villası’nın Dionysos frizi ve Aldobrandini Düğünü örnekleriyle karşılaştırılabilir). Bu bakış açısıyla, sözde “Psykhe”nin insani dünyadan bir gelin olarak tanımlanması önerilmiştir. Ancak bu, ilahi alanla yakın etkileşim içinde olan bir insani dünyadır. Eros’un yanındaki insan gelin, hem mütevazı hem de çekici bir duruş ve tavır sergileyen giysilerle betimlenmiştir; bu da ünlü Aphrodite Sosandra’yı çağrıştırır. Bu heykel tipi özellikle Zeugma’da olmak üzere Roma İmparatorluğu’nun doğu kesimlerinde çok iyi biliniyor olmalıydı; nitekim İS 2. yüzyılın ikinci yarısına ait çok sayıda kopyanın dolaşımıyla bu durum belgelenmiştir. Araştırmacılar ayrıca, evin sahibinin muhtemelen IV. Scythica Lejyonu’na mensup, kozmopolit bir ortamda yaşayan üst düzey bir Roma askeri olabileceğini önermektedi
The effect of magnesium on tumor-associated myeloid cells in Triple-Negative Breast Cancer (TNBC)
No full textÜçlü negatif meme kanseri (ÜNMK), hormonal ve HER2 reseptörlerinin ekspresyonunun bulunmadığı, invaziv ve tedaviye dirençli bir alt tiptir. Bu tümörlerde mikroçevre, genellikle artmış PD-L1 ekspresyonu ve CD8⁺ T hücre infiltrasyonu ile karakterize immün baskılayıcı bir yapıya sahiptir. Myeloid kaynaklı baskılayıcı hücreler (MDSC), bu ortamda T hücre yanıtlarını baskılayarak tümör progresyonunu destekler. MDSC’lerin immün regülasyondaki kritik rolleri, bu hücreleri hedefleyen tedavileri önemli hale getirmektedir. Bu çalışmada, MgCl₂ formundaki magnezyumun MDSC’ler ve lenfositler üzerindeki etkileri in vitro, ex vivo ve in vivo düzeylerde incelenmiştir. BV-2, N9 ve Raw 264.7 miyeloid hücre hatlarında MgCl₂’nin seçici sitotoksik etkisi gösterilmiş; MgCl₂ varlığında 4T1 meme kanseri hücrelerinin proliferasyonunun azaldığı gözlemlenmiştir. Ex vivo kültürlerde splenosit canlılığı ve proliferasyonu artmıştır. Sağlıklı farelerde düşük (30 mg/kg) ve yüksek (60 mg/kg) doz uygulamaları, miyelopoezi artırmış ve CD4⁺/CD8⁺ T hücre oranlarını etkilemiştir. 4T1 tümör modelinde yüksek doz ve tümör sonrası MgCl₂ uygulamaları sağ kalımı anlamlı şekilde artırmıştır. Bu gruptan izole edilen MDSC alt grupları, T hücrelerini baskılamak yerine proliferasyonlarını desteklemiştir. Sonuçlar, MgCl₂’nin MDSC fonksiyonlarını yeniden programlayarak anti-tümöral bağışıklığı güçlendirebileceğini göstermektedir.Triple-negative breast cancer (TNBC) is an invasive and treatment-resistant subtype characterized by the absence of hormonal and HER2 receptor expression. Its tumor microenvironment (TME) often exhibits an immunosuppressive structure with increased PD-L1 expression and CD8⁺ T cell infiltration. Myeloid-derived suppressor cells (MDSCs) contribute to this suppressive milieu by inhibiting T cell responses, thereby promoting tumor progression. Given their pivotal role in immune regulation, targeting MDSCs is considered a promising immunotherapeutic strategy. This study investigates the selective effects of magnesium in the form of MgCl₂ on MDSCs and lymphocytes at in vitro, ex vivo, and in vivo levels. MgCl₂ showed selective cytotoxicity in myeloid cell lines (BV-2, N9, Raw 264.7), and its presence reduced the proliferation and survival of 4T1 breast cancer cells in co-culture. Ex vivo cultures revealed enhanced splenocyte viability and proliferation. In healthy mice, low (30 mg/kg) and high (60 mg/kg) doses of MgCl₂ induced myelopoiesis, increased neutrophil precursors, and modulated CD4⁺/CD8⁺ T cell distributions. In vivo experiments using the 4T1 tumor model demonstrated that high-dose, post-tumoral MgCl₂ administration significantly improved survival. M-MDSC and G-MDSC subsets isolated from these animals supported, rather than suppressed, T cell proliferation. These findings indicate that MgCl₂ not only inhibits tumor growth but also reprograms MDSC phenotype and function to promote anti-tumor immune responses. Overall, the study suggests that magnesium modulates MDSC function in a dose- and timing-dependent manner, potentially opening new avenues for immunotherapy in TNBC
Investigating the impact of STEAM based science activities on the science engagement and scientific creativity of artistically talented middle school students
No full textMevcut tez çalışmasında; STEAM temelli fen bilimleri etkinliklerinin, sanatsal yetenekli ortaokul öğrencilerinin fene katılım ve bilimsel yaratıcılıklarına etkisi araştırılmaktadır. Çalışmada tek grup ön test – son test deneysel tasarım kullanılmaktadır. Araştırma Bursa Uludağ Üniversitesi Devlet Konservatuvarı Müzik ve Bale İlköğretim Kurumu’nda, 2024-2025 yılı güz döneminde ortaokul seviyesinde öğrenim gören 5. sınıfta 18 ve 6. sınıfta 18 olmak üzere toplam 36 öğrenci ile gerçekleştirilmiştir. Bu çalışmada kolay ulaşılabilir örnekleme yöntemi kullanılmaktadır. Araştırmanın ana problem cümlesi; ‘STEAM temelli fen bilimleri etkinliklerinin, sanatsal yetenekli ortaokul öğrencilerinin fene katılım ve bilimsel yaratıcılıklarına etkisi var mıdır?’ şeklinde belirlenmiştir. Bu kapsamda beşinci ve altıncı sınıflar için 3 hafta sürecek ve haftada 3 ders olmak üzere uygulanacak STEAM temelli fen bilimleri etkinliklerini içeren ders planları oluşturulmuştur. Beşinci sınıflarda ‘Kuvveti Tanıyalım’ ünitesi, altıncı sınıflarda ‘Kuvvet ve Hareket’ ünitesi STEAM temelli fen bilimleri etkinlikleri ile MEB müfredatına uygun olacak şekilde öğretilmiştir. STEAM temelli fen bilimleri etkinliklerinin öğrencilerin fene katılım ve bilimsel yaratıcılıklarına etkisini ölçmek için etkinlikler öncesinde ve sonrasında öğrencilere bilimsel yaratıcılık ve fene katılım ölçekleri uygulanmıştır. Ölçekler betimsel istatistik ile analiz edilmiştir ve bağımlı gruplar t – testi olarak incelenmiştir. Sonuçlar incelendiğinde 5. sınıf ve 6. sınıf düzeyinde uygulanan STEAM temelli etkinliklerin öğrencilerin bilimsel yaratıcılık düzeylerini önemli ölçüde arttırdığı görülmektedir; fene katılım düzeylerinde ise istatistiksel açıdan anlamlı bir fark bulunamamıştır. Öneriler olarak, farklı illerde bulunan konservatuvarlarda yeni araştırmalar gerçekleştirilmesi; çalışmanın aynı ya da farklı sınıf düzeylerinde ve konularında uygulanarak etkisinin araştırılması; uygulanmış STEAM etkinliklerinin farklı değişkenler açısından değerlendirilmesi; farklı alanlardaki özel yetenekli öğrenciler ile çalışılması; etkinliklerin farklı eğitim yöntemleri ile denenmesi sunulmaktadır.In the current thesis, the effect of STEAM-based science activities on the science engagement and scientific creativity of artistically gifted middle school students is investigated. The study uses a one-group pretest-posttest experimental design. The research was conducted with a total of 36 students, 18 in the 5th grade and 18 in the 6th grade, studying at the middle school level in the fall semester of 2024-2025 at Bursa Uludağ University State Conservatory Music and Ballet Primary School. In this study, convenience sampling method was used. The main problem statement of the study was determined as; 'Do STEAM-based science activities have an effect on the science participation and scientific creativity of artistically gifted middle school students? In this context, lesson plans were created for the fifth and sixth grades, including STEAM-based science activities to be implemented for 3 weeks and 3 lessons per week. The 'Let's Recognize Force' unit in the fifth grade and the 'Force and Motion' unit in the sixth grade were taught with STEAM-based science activities in accordance with the MEB curriculum. In order to measure the effect of STEAM-based science activities on students' science engagement and scientific creativity, scientific creativity and science engagement scales were applied to students before and after the activities. The scales were analyzed with descriptive statistics and dependent groups were analyzed as t-test. When the results are examined, it is seen that STEAM-based activities implemented at the 5th and 6th grade levels significantly increased the scientific creativity levels of the students; however, no statistically significant difference was found in the level of science engagement. As suggestions, it is suggested to conduct new research in conservatories located in different provinces; to investigate the effect of the study by applying it at the same or different grade levels and subjects; to evaluate the implemented STEAM activities in terms of different variables; to work with gifted students in different fields; to test the activities with different educational methods
New accurate deep learning model for diabetic retinopathy detection utilizing sequential pre-processing and transfer learning
No full textThis study considers the detection of Diabetic Retinopathy (DR) using deep learning. DR affects 80% of diabetic patients worldwide and is the second leading cause of blindness. Many studies have shown that early diagnosis and treatment are critical to prevent disease progression. The contribution of this study is the development of an accurate DR detection algorithm and corresponding model, where hemorrhages were brought to a more apparent form by an efficient processing pipeline. To handle limited DR data resources and to make the visibility of bleeding in the eye more apparent, we have developed an efficient deep learning model by combining data augmentation, pre-processing, transfer learning, and adaptation of a compatible CNN. The employed dataset comprises fundus images of individuals, which are categorized into five stages of DR. For evaluation, comprehensive ablation studies are conducted on the model. Next, the developed model is evaluated against state-of-theart algorithms and demonstrates promising results in key metrics. Particularly, the model yields 96.95% accuracy and introduces a false negative rate below 1%. Efficient metrics of the study minimize the risk of missed diagnoses and reduce the likelihood of severe vision loss in diabetic patients. Therefore, our model has the potential to contribute to clinical patient care
Optimization of process parameters in rotary ultrasonic-assisted drilling of quartz
No full textProcessing hard and brittle quartz glass using traditional production methods is challenging. Thus, ultrasonic machining is the recommended method for working with these types of materials. This paper explores the machining of quartz material through rotary ultrasonic drilling (RUD) using a trepanning tool. The study investigates the effect of ultrasonic power, tool rotational speed, feed rate, and pecking drilling depth parameters on chipping area (CA), material removal rate (MRR), and surface roughness (SR). The design of the experiments utilized response surface methodology (RSM) with the Box-Behnken design. The optimal process parameters (26th) were determined by ranking the gray relational grade (GRG) in gray relational analysis (GRA) based on the results of all 27 experiments. The settings of the 26th experiment were as follows: ultrasonic power (P) was set to 90%, tool rotational speed (n) to 1300 rpm, feed rate (Vf) to 30 mm/min, and pecking drilling depth (dp) to 0.75 mm, and the results were CA = 56.96 mm2, SR = 1.222 mu m and MRR = 162.68 mm3/s. The optimum parameters (P = 60%; n = 1600 rpm; Vf = 30 mm/min; dp = 0.40 mm) were determined by calculating the average GRG for each parameter level using GRA. The desirability approach in multi-response optimization was used to determine the optimum values for the parameters (P = 61.52%; n = 1478.79 rpm; Vf = 28.18 mm/min; dp = 0.69 mm). The RSM analysis revealed that these settings resulted in a minimum CA of 55.93 mm2, a minimum SR of 0.938 mu m, and a maximum MRR of 147.63 mm3/s. Additional experiments were conducted with the RUD and CD (conventional drilling) method with the ideal configuration. As per the GRA analysis, the parameter of rotating speed of the tool had the most influence on its results of CA, SR, and MRR. ANOVA analysis revealed that the factors with the most effect were P for SR, n for CA, and Vf for MRR
The development of a fuzzy logic system using MATLAB for early detection of hereditary cancer in BRCA1/2 negative cases
No full textThe purpose of our study is to expedite cancer diagnosis through the development of software for rapid detection of hereditary breast cancer (BC) with negative BRCA1/2 on MATLAB, utilizing a fuzzy logic system with several variants of genes associated with BC. This system serves as a clinical decision-support tool, assisting in early classification and interpretation of genetic variants by combining clinical and genetic data. Clinical data were obtained from Erciyes University Faculty of Medicine Department of Medical Genetics and Uludağ University Faculty of Medicine Department of Medical Genetics. 488 individuals were studied. Only 90 of them were relevant to our investigation since their BRCA1/2 genes did not exhibit notable genetic mutations. We examined 16 distinct breast cancer risk factors and focused on mutations related to 18 hereditary BC genes. The collected data were integrated into the developed system, and various membership functions were given varying degrees of possibility, ranging from 0 to 1, depending on their participation in input clusters. After the system was trained on 90 cases and validated on six independent patients, its accuracy was assessed, yielding reliable results. Following the training phase, outcomes revealed the presence of two pathogenic variants at 0.92 (92%), two benign variants at 0.25 (25%), and two variants of unknown significance at 0.5 (50%). Given the high incidence of breast cancer, early prediction is paramount. Despite the emergence of fuzzy logic systems in medical applications, limited research akin to our study exists. The establishment of this artificial intelligence software holds promise for advancing the early detection of BC in future clinical applications
Effect of pre-and post-harvest processing on the chemistry and functionality of fruits and vegetables preface
No full textFR4 ve aluminyum PCB malzemelerinin MAC metodu kullanılarak titreşim davranışlarının incelenmesi
No full textIn this study, plates made of two different materials used in PCB (Printed Circuit Board), FR4 and Aluminum, have been investigated by experimental modal analysis (EMA) and finite element method (FEM) modal analysis. Firstly, dynamic structural characteristics of plates, consisting of modal shapes, natural frequencies have been calculated by the help of ANSYS® R23 software. Afterwards, to determine the vibrational characteristics of the plates by EMA, roving hammer, roving accelerometer, and modal shaker tests have been performed by the help of DEWESOFT® data acquisition hardware and its corresponding software. Frequency response function (FRF) is measured by EMA software and FRF were exported to be analyzed by MEScope® modal analysis software. In MEScope® software, FRF’s between excitation points and measurement points were matched with corresponding points of the structure geometry. Modal assurance criteria (MAC) were calculated between the EMA and FEA modal shapes. Results of impact hammer test method obtained to closer to the results of numerical analysis than other methods. It has also been observed that the dimensions of the variable plates affect the MAC results. Additionally, importance of the gravity and mass balance on the structure were analyzed specially for thin structures, indicated actions to cope with mass balance issue.Bu çalışmada, PCB'de (Baskılı Devre Kartı) kullanılan iki farklı malzeme olan FR4 ve Alüminyumdan yapılmış plakalar, deneysel modal analiz (EMA) ve sonlu elemanlar yöntemi (FEM) modal analizi ile incelenmiştir. İlk olarak, plakaların modal şekilleri, sönümleme oranları, doğal frekanslarından oluşan dinamik yapısal özellikleri ANSYS® R23 yazılımı yardımıyla hesaplanmıştır. Daha sonra, plakaların titreşim özelliklerini EMA ile belirlemek için DEWESOFT® veri toplama donanımı ve yazılımı ile birlikte darbe çekici gezdirme, ivmeölçer gezdirme ve modal sarsıcı testleri gerçekleştirilmiştir. Frekans tepki fonksiyonu (FRF), EMA yazılımı ile ölçülmüş ve FRF’den elde edilen veriler numerik analiz ile karşılaştırılmak için MEScope® yazılıma aktarılmıştır. MEScope® yazılımında, tetikleyici noktalar ile ölçüm noktaları arasındaki FRF'ler yapı geometrisinin ilgili noktaları ile eşleştirilmiştir. EMA ve FEA modal şekilleri arasında modal güvence kriterleri (MGM) hesaplanmıştır. Darbe çekici test yönteminin sonuçlarının diğer modal test yöntem sonuçlarına göre, numerik analizlere daha yakın olduğu görülmüştür ve mod şekillerinin benzerliği açıklanmıştır. Değişken plakaların boyutlarının MGM sonuçlarını etkilediği de gözlemlenmiştir. Ayrıca, yerçekimi ve kütle dengesinin yapı üzerindeki önemi özellikle ince yapılar için analiz edilmiş ve kütle dengesinden kaynaklanan sorunlar için aksiyonlar belirtilmiştir
The turkish version of the self-care behaviors scale for rheumatoid arthritis patients: Cross-cultural adaptation and psychometric evaluation
No full textBackgroundSelf-care behaviors play an important role in disease management and improving the health outcomes of rheumatoid arthritis (RA) patients. However, currently available Turkish instruments to measure self-care behaviors in RA patients are not disease-specific or have low reliability. The aim of this study was to adapt the Self-Care Behaviors Scale (SCBS), developed specifically for RA patients, into Turkish and evaluate its psychometric properties. MethodsThe study was conducted with 378 RA patients admitted to the Rheumatology Outpatient Clinic of a university hospital. Content validity, construct validity, internal consistency and test-retest reliability examined the psychometric properties of the scale. ResultsThe SCBS-T with its seven factors and 25 items was found to be valid (KMO = 0.957; Bartlett's test chi 2 = 6614.69, p < 0.001), to explain 67.80% of the total variance, and to have good fit indices (chi 2/df = 2.920; GFI = 0.861; CFI = 0.925; RMSEA = 0.078; TLI = 0.912; SRMR = 0.045). The scale's overall Cronbach's alpha coefficient was 0.86, while the subscales ranged between 0.74 and 0.81. One-week interval test-retest reliability was 0.81. ConclusionsThe high validity and reliability results of the SCBS-T indicate that the scale will form a strong basis for its routine use by health professionals in clinical settings and for the development of educational programs on the self-care of RA patients