İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
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Topoloji optimizasyonu tabanlı hafifletilmiş şasi tasarımı: Otonom bir model aracın yapısal verimliliği üzerine uygulama
No full textThis study aims to enhance structural efficiency and achieve material savings by employing the topology optimization method for the lightweight design of an autonomous model vehicle chassis. During the design process, the penalty-based Solid Isotropic Material with Penalization (SIMP) method, available within ANSYS Academic software, was utilized. Initially, a structural analysis of the chassis was conducted, followed by the application of topology optimization based on the finite element method (FEM) results. Through iterative solutions under specified loading conditions and boundary constraints, a mass reduction of approximately 27% was achieved compared to the initial geometry. Despite the reduction in mass, the design maintained its structural integrity. Graphical analyses indicated that the optimization process reached convergence after the fifth iteration, with a stabilized distribution of material. The results demonstrate the potential of topology optimization to develop low-cost, lightweight, yet robust structural solutions, emphasizing its effectiveness as an engineering tool in systems where weight reduction is critical, such as autonomous model vehicles
A comparative study of deep learning models for automated liver and tumor segmentation in 2d contrast-enhanced MRI images
No full textThis paper presents a comprehensive investigation into deep learning techniques for the automated segmentation of the liver and tumors from 2D abdominal contrast-enhanced Magnetic Resonance Imaging (MRI) slices. Addressing a significant challenge in medical image analysis, our study leverages the public ATLAS dataset [1], using a selection of 60 3D abdominal MRI scans, from which we extracted approximately 3,750 2D slices for model training and evaluation. The core objective was the precise identification and delineation of both the liver organ and any intrahepatic lesions. A comparative analysis was conducted on three U-Net-based architectures: the standard Attention U-Net model incorporating EfficientNet-b3 and CBAM but without Focal Loss, the Attention U-Net model with integrated Focal Loss, and the ResNet34-Based U-Net model. To optimize performance, we explored the efficacy of different loss functions, namely DiceLoss and a hybrid DiceLoss with Focalcoss. Our findings are promising: Among the evaluated models, the ResNet34-Based U-Net demonstrated the highest performance with a Dice score of 91.36% and an IoU score of 89.52%. It was followed by the Attention U-Net with Focal Loss, which achieved 86.41% Dice and 81.61% IoU scores, and the standard Attention U-Net, which obtained 85.93% Dice and 81.19% IoU scores. These results underscore the significant potential of our 2D-based methodology to enhance the precision and efficiency of liver and tumor detection from abdominal scans, offering a valuable tool to support clinicians in early diagnosis and to alleviate their workload
A randomized controlled trial of internet-based cognitive behavioral therapy (iCBT) and EMDR-flash technique (iEMDR-FT) for improving mental health in breast cancer patients
No full textThis study aims to compare the effectiveness of internet-based Cognitive Behavioral Therapy (iCBT) and internet-based Eye Movement Desensitization and Reprocessing (EMDR) Flash Technique (iEMDR-FT) in reducing fear of cancer recur rence, traumatic stress, anxiety, depression, and increasing the quality of life among patients diagnosed with breast cancer. A randomized controlled trial was conducted with a sample of patients, equally divided into two treatment groups. The iCBT program was administered over 7 weeks, while the iEMDR-FT was delivered in three sessions in three days. The participants were given a sociodemographic data form, Posttraumatic Stress Disorder Control List DSM-5 (PCL-5), Fear of Cancer Recurrence Scale, Depression-Anxiety-Stress 21 scale (DASS-21), and World Health Organization Quality of Life Scale Short Form. Participants were assessed before, immediately after, and three months post-intervention. The mean age of the participants was 43.79 (7.45) years. In comparing the two groups, a statistical difference was found only in the age variable (p=0.025). As a result, there was no significant difference between the two groups when sociodemographic and cancer-related ratings were compared (p>0.05). It was determined that the change in iEMDR-FT scores in all scales was not statistically significantly different compared to the iCBT group (p>0.05). Initial analysis indicates that both iCBT and iEMDR-FT resulted in notable decreases in traumatic stress, fear of cancer recurrence, anxiety, and depression among breast cancer patients. However, this therapeutic improvement is similar in both applications. This result supports the argu ment that two methods with similar effectiveness can be used as alternatives to each other in treatment
The role of breast milk in the formation of the newborn’s circadian rhythm
No full textCircadian rhythm, also called the biological rhythm, refers to the repetition of an individual's 24-hour biochemical, physiological, and behavioral cycles. The sleep wake cycle is the most basic circadian rhythm. The hormones that play a key role in regulating it are cortisol and melatonin. In the first years of life, breast milk plays an important role in the formation of the circadian rhythm and helps the newborn adapt to its new environment outside the womb. The composition of breast milk is quite variable, and this variability provides the baby with clues about the outside world. Breast milk secreted during the day has a high lactose content, which provides energy for the baby, improves learning ability, and quenches thirst. Breast milk secreted at night has a lower lactose concentration but higher fat and melatonin concentrations. In the case of feeding with expressed milk, the time of expression and the time of feeding should align to maintain the sleep-wake cycle
The effects of light and vibration on the correction of lower incisor crowding with aligners
No full textObjective: To compare the effects of low-frequency vibration (LFV), photobiomodulation (PBM), and their combination (HOT) on the rate of mandibular incisor alignment during clear aligner therapy. Methods: This retrospective study included 89 patients treated with a single clear aligner system for mild-to-moderate mandibular anterior crowding. Patients were assigned to four groups: control (n=19), LFV (n=26), PBM (n=21), and HOT (n=23). LFV [30 Hz, 0.25 N (≈25 g)] and PBM (850 nm, 16×5 mm LEDs, ≈9.5 J/cm2 ) devices were used daily for 20 minutes in relevant groups. The primary outcome was the change in Little’s Irregularity Index at baseline (T0), 28 days (T1), 48 days (T2), and 62 days (T3). Statistical analyses included one-way ANOVA, repeated measures ANOVA, and Pearson’s correlation. Results: The HOT group showed significantly greater crowding reduction compared to all other groups (p<0.05). LFV and PBM alone were not significantly different from the control. Within-group analysis revealed significant reductions in all groups over time, with the HOT group showing consistent improvements at each interval. Correlation analyses revealed no significant associations between device usage or aligner wear time and crowding reduction. Conclusion: Combining LFV and PBM during clear aligner therapy produced greater short-term acceleration of mandibular incisor alignment than either modality alone. Further randomized controlled trials are warranted to confirm long-term efficacy and safety
Senior nursing students' perspectives on nursing management: A qualitative study
No full textBackground Theoretical and practical classes in nursing management are part of nursing programmes; however, students often state a need for more preparation to apply leadership and management skills in clinical settings, highlighting the need for innovative educational approaches. This gap between theoretical preparation and the practical application of leadership and management skills underscores the importance of understanding students’ views on what constitutes effective nurse management. Aim This study aimed to explore final-year nursing students’ perspectives on the essential skills, practice and attitudes that nurse managers should demonstrate. Methods This is a descriptive qualitative study. It comprises written narratives of 35 senior undergraduate nursing students. Data were collected between 23 November 2023, and 4 December 2023. Descriptive thematic analysis was undertaken. Results Five themes were identified: (1) What makes a successful nurse manager, (2) Perspectives on effective leadership in nursing, (3) Fostering empowerment in the nursing team, (4) Building and strengthening team cohesion in nursing and (5) Effective care delivery models. Students believe nurse managers should take on a more effective leadership role. Conclusions Nursing students’ reflections can be utilised to update nursing curricula, to improve student leadership and managerial knowledge and skills as they enter the workforce
Protetik diş hekimliğinde fotopolimer dental reçineler
No full textProtetik diş hekimliğinde kullanılan üretim yöntemleri, son yıllarda dijital teknolojilerin gelişimine paralel olarak önemli bir dönüşüm süre cinden geçmektedir. Geleneksel döküm, presleme ve frezeleme temelli üretim yöntemlerinin yerini, bilgisayar destekli tasarım ve üretim sistem leri (Computer-Aided Design/Computer-Aided Manufacturing – CAD/ CAM) ile birlikte eklemeli üretim teknolojileri (Additive Manufacturing – AM) almaya başlamıştır. Bu teknolojiler, üretim doğruluğunu ve işlem hızını artırarak materyal kullanımında verimlilik sağlamış, aynı zaman da kişiye özgü protetik restorasyonların üretilmesini mümkün kılmıştır
Febril konvülsiyonlu olgularımızın demografik, klinik, laboratuvar bulguları ve tedavilerinin değerlendirilmesi: Tanımlayıcı araştırma
No full textObjective: In this study, we aimed to determine the sociodemographic, clinical and laboratory characteristics, responses to treatment options, and risk factors for the development of epilepsy in cases who presented to our clinic with febrile convulsions (FC) and were diagnosed with FC. Material and Methods: 200 patients who applied to Trakya University Faculty of Medicine, Department of Pediatrics Outpatient Clinic and Child Neurology Polyclinic between January 2014-December 2018 and were diagnosed with febrile convulsion were evaluated retrospectively. In recurrent simple febrile convulsions and in all complicated febrile convulsions, electroencephalography (EEG) was performed. In case of abnormal EEG findings, appropriate treatment was started. Results: The male/female ratio was 1.22/1, 78% were term births. The average age at diagnosis was 21.82±12.69 months. 52.5% were complicated. The common source of fever was upper respiratory tract infection (83%). 10% had a family history of epilepsy and 25% had a history of febrile convulsions. The recurrence rate was 22.5%. Abnormal EEG was detected in 8% of the patients. Patients with recurrence had higher platelet counts and patients with epilepsy had higher C-reactive protein levels. Conclusion: Epilepsy was observed in %13 of febrile convulsions. The rate of epilepsy diagnosis was high in those with abnormal EEG (81%). As a result; monitoring of febrile convulsions is important due to the increased risk of epilepsy and frequent recurrence compared to the general population. Although we found no significant difference between treatment options in preventing recurrence, rectal diazepamand antipyretics may be preferred since it is easy to apply and has few side effects.Amaç: Bu çalışmamızda, ateşli havaleyle kliniğimize başvurup febril konvülsiyon tanısı alan vakaların sosyodemografik, klinik, laboratuvar özelliklerini, tedavi seçeneklerine yanıtlarını, epilepsi gelişimi açısından risk faktörlerini belirlemeyi amaçladık. Gereç ve Yöntemler: Ocak 2014-Aralık 2018 arasında Trakya Üniversitesi Tıp Fakültesi Çocuk Sağlığı ve Hastalıkları Genel Pediatri ve Çocuk Nörolojisi Polikliniği'ne başvurup febril konvülsiyon tanısı alan 200 hasta retrospektif olarak değerlendirildi. Tekrarlayan basit febril konvülsiyonlarda ve tüm komplike febril konvulsiyonlarda poliklinik takiplerinde en geç bir haftada elektroensefalografi (EEG) çekildi ve anormal bulgusu olanlarda uygun tedavi başlandı. Bulgular: Olguların erkek/kız oranı 1,22/1, %78i term doğumdu. Tanı yaşı ortalama 21,82±12,69 aylıktı. %52,5'u komplike febril konvulziyondu. En sık ateş odağı üst solunum yolu enfeksiyonuydu. (%83). Vakaların %10'unda ailede epilepsi öyküsü, %25'inde febril konvülsiyon öyküsü vardı. Rekürrens oranı %22,5'ti. Hastaların %8'inde anormal EEG saptandı. Rekürrensi olan hastaların trombosit değerleri, epilepsi gelişen hastaların C-reaktif protein seviyeleri daha yüksekti. Sonuç: Febril konvülsiyonların %13'ünde epilepsi geliştiği görüldü. Anormal EEG'si olanların (%81) epilepsi tanısı alma oranı yüksek tespit edildi. Sonuç olarak; febril konvülsiyonların genel popülasyona göre artmış epilepsi riski ve rekürrensin sık görülmesi nedeniyle izlemi önemlidir. Rekürrensi önlemede tedavinin belirgin farkı olmasa da rektal diazepam ve antipiretik tercihleri uygulaması kolay, yan etkisi az gruptadır
Artificial intelligence in planetary science and astronomy: Applications and research potential
No full textArtificial Intelligence (AI) is one of the most influential fields of the 21st century (Zhang et al., 2021). Rich, E (2019) candidly described it as “the study of how to make computers do things which, at the moment, people do better”, today AI often surpasses human ability in tasks like large scale data mining and pattern recognition - its true strength. AI’s subfields - Machine Learning (ML) and deep learning (DL), play a critical role in expanding the usage to a vast variety of fields like planetary science, astronomy, earth observations, and remote sensing, just to name a few. There is an expected inclination towards incorporating AI more frequently in the studies of planetary science given the vast and complex nature of planetary data. In fact, AI has already been instrumental in extracting meaningful insights and advancing research in both interplanetary and astronomical studies. In planetary sciences, several AI techniques have been employed in order to bridge gaps in our understanding of the varied patterns and occurrences for studying the natural features observable from the data returned by scientific payloads. For example, PCA and cluster analysis can help in detecting patterns of compositional variation from multi and hyper-spectral imagery (Moussaoui et al., 2008; D’Amore & Padovan, 2022). Furthermore, to study specific features and patterns in their occurrences, correlations with neighbouring features; unsupervised algorithms and more complex -supervised techniques can be helpful depending on the scale of the task. From simple methods of unsupervised learning like clustering used to study the spectral signatures of Jezero crater on Mars (Pletl et al., 2023) to applying large language models to track asteroids affected by gravitational effects which alter the asteroid’s orbit (Carruba et al., 2025), such applications highlight the prospects of AI in the field of planetary science. Henceforth, to develop a deeper understanding of the potential and applications of ML, below is a typical AI workflow
Preparation and characterization of an acrylated-coumarin-containing photo-crosslinked thiol-ene network: Investigation of the free-volume, thermal, UV, and photoluminescence properties
No full textCoumarin, a versatile compound, has attracted great interest in polymer science due to its unique properties and diverse applications. The use of coumarins in polymer research opens avenues for the development of materials with improved functionalities. In this study, an acrylated coumarin (a-coumarin) compound containing polymeric films was obtained via UV curing through a thiol-ene click reaction with a free radical mechanism. The obtained a-coumarin-containing polymeric films were subjected to functional characterization using FTIR and NMR analyses and thermal characterization via DSC and TGA. UV–vis and PL analyses were performed to determine the optical properties. Using positron anni hilation lifetime spectroscopy (PALS), the free volume and proportional free volume fraction of the films were analyzed both below and above the glass transi tion temperature (Tg). The Tg values obtained from PALS were several degrees lower than those obtained via DSC. A-coumarin additives inhibit segmental mobility, hence reducing the proportional free volume fraction and increasing the Tg. This study is the first in the literature to investigate the free volume properties of coumarin-containing polymeric films. The study reveals the impact of a-coumarin on thermal, optical, and free volume properties, paving the way for the design of advanced functional materials