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Modelling intra-sinus fluid movements and drainage through computational fluid dynamics before and after maxillary sinus augmentation: a simulation-based pilot study
No full textObjectives: Sinus lifting, a procedure to augment bone in the maxilla, may cause complications such as sinusitis due to impaired drainage. This study aimed to assess how sinus lifting impacts airflow in the sinus cavity, which is essential for patients undergoing dental implants. Using computational fluid dynamics (CFD), this research analyzed airflow changes after sinus floor elevation, offering insights into the aerodynamic consequences of the procedure. Methods: Digital modeling and CFD analysis were performed using patient cone-beam computed tomography data. Three different sinus elevation scenarios, each with varying implant heights, were simulated. Airflow simulations were conducted to assess how reshaping the sinus cavity affects aerodynamics and airflow dynamics. Nasal resistance, calculated through pressure drops and flow rates, and wall shear stress, indicating potential mucosal damage, were evaluated. Results: Although some airflow changes occurred post-surgery, the implants primarily affected the front and rear of the elevated area, with little impact being seen on air entry points. Conclusions: Maxillary sinus lifting for dental implant placement may impair sinus drainage, especially at higher elevations, increasing the risk of mucosal damage due to intensified airflows in the reduced sinus volume. A more uniform, simplified intra-sinus structure may enhance fluid dynamics and reduce complications.Foundation of Scientific Research Committee of the Istanbul Medipol University, Istanbul, Turke
Long terms results of temporal facelift: 6 years of experience in 250 cases
No full textBackground: Temporal facelift (TFL) is an innovative technique for lifting the upper and mid-face. It is characterized by a unique dissection plane above the subgaleal fascia, which seamlessly transitions into the sub-superficial muscular aponeurotic system (SMAS) layer in the mid-face. This approach enables comprehensive mid-face elevation, robust canthopexy, and a significant brow lift in various vectors. Objectives: The authors present their experience with 250 TFL procedures over a period of 6 years. Patients and Methods: This retrospective study analyzed 250 of 441 patients who underwent TFL surgery. The surgical procedures, conducted under general anesthesia by a senior surgeon following the TFL method, involved a vertical-vector deep-plane mid-face lift, canthopexy, and brow-lift triad. Close monitoring of complications and detailed photographic documentation of the outcomes were performed. Postoperative care included taping the operation area to reduce swelling, with subsequent follow-up examinations and interventions such as lymphatic massage and botulinum toxin injections for asymmetric brow movements or steroid injections for excessive mid-face swelling. Results: Among 250 patients (248 female, 2 male; mean age, 37 y), unilateral neuropraxia of the frontal branch of the facial nerve occurred in 5.6% and resolved spontaneously within 2.8 months. Persistent dimples (2.8%) resolved by the fifth postoperative month. Six patients (2.4%) underwent revision surgery with no observed complications like hematoma, necrosis, infection, or seroma. Conclusions: The TFL technique represents a significant advancement in upper and mid-face lifting procedures and offers several advantages over the traditional methods
Predictor scales of cognitive factors affecting physical activity in individuals surviving cancer: psychometric properties of Turkish versions
No full textBackground: Increasing physical activity in individuals surviving cancer is crucial in reducing treatment-related side effects and recurrence. Valid and reliable measurement tools are needed that will enable the factors affecting exercise to be addressed holistically and theoretically. This study aimed to adapt the Exercise Goal-Setting Scale, Exercise Planning and Scheduling Scale, Multidimensional Outcome Expectations for Exercise Scale, and Physical Activity Neighborhood Environment Scale into Turkish language and to explore psychometric properties of the Turkish versions of these scales in individuals surviving cancer. Methods: This methodologically designed research collected data from 153 participants at a hospital in Istanbul, Türkiye. The scales used in the study were adapted to the Turkish language through forward and backward translation and expert opinion. Content validity was assessed with a 2-week test-retest reliability, Cronbach's α reliability coefficient for stability, item-total correlation, and confirmatory factor analysis. Results: The scales showed good content validity (CVI = 0.95-0.99). Internal consistencies were acceptable to excellent (Cronbach's α =.79-.94), and moderate to good reproducibility estimates were observed (r =.67-.84). The MOEES factor structure also showed excellent fit. Conclusions: This study demonstrates that the adapted scales evaluated are valid and reliable for examining physical activity based on social cognitive processes in individuals surviving cancer in Türkiye. The scales examined in the study can be used to determine the cognitive factors affecting activity and to plan effective programs when providing physical activity counseling to individuals surviving cancer in Türkiye
Applications of deep learning in alzheimer's disease: a systematic literature review of current trends, methodologies, challenges, innovations, and future directions
No full textAlzheimer’s Disease (AD) constitutes a significant global health issue. In the next 40 years, it is expected to affect 106 million people. Although more and more people are getting AD, there are still no effective drugs to treat it. Insightful information about how important it is to find and treat AD quickly. Recently, Deep Learning (DL) techniques have been used more and more to diagnose AD. They claim better accuracy in drug reuse, medication recognition, and labeling. This essay meticulously examines the works that have talked about using DL with Alzheimer’s disease. Some of the methods are Natural Language Processing (NLP), drug reuse, classification, and identification. Concerning these methods, we examine their pros and cons, paying special attention to how easily they can be explained, how safe they are, and how they can be used in medical situations. One important finding is that Convolutional Neural Networks (CNNs) are most often used for AD research and Python is most often used for DL issues. Some security problems, like data protection and model stability, are not looked at enough in the present research, according to us. This study thoroughly examines present methods and also points out areas that need more work, like better data integration and AI systems that can be explained. The findings should help guide more research and speed up the creation of DL-based AD identification tools in the future
Impact of global capabilities on performance in international logistics companies
No full textPurpose: In order to make a difference in a globally competitive environment, companies should analyze their competitors, which is one of the factors around them, well, do research, observe the environment and know how to adapt. For this purpose, the research examines the effects of competitive intensity and marketing and sales capabilities, together with the global capabilities of logistics companies operating internationally (third-party logistics companies (3PL)), which are examined. Design/methodology/approach: To establish and test the model, a sample of 504 participants working at senior levels in internationally operating logistics companies (third-party logistics companies (3PL)) with their headquarters in Istanbul was taken and a scale consisting of a total of 32 statements was presented to them. Analyses were performed using Jamovi and SmartPLS 3.3.5. This program was used because, in addition to estimating path models with latent variables, it also calculated standard results evaluation criteria. First, the results of factor analysis are given. After these analyses were completed, the hypotheses were tested. Findings: This research is supported by hypotheses as a result of the analysis that global capabilities are an important factor for logistics companies at the international level, and that the competitive intensity also affects the performance outputs and that marketing and sales capabilities also have an impact. Research limitations/implications: Since data are collected from logistics companies operating globally, it is necessary to pay attention when the analysis results are compared with different sectors. Because the intensity of competition may vary depending on the sector and market in which companies operate. At the same time, the data were collected from authorized white-collar employees working at a senior level in logistics companies. Because, in terms of the level of being able to answer the questions about the variables examined in the research model, data were collected from high-level officials. Practical implications: It is getting harder and harder to compete on a global scale by going beyond national borders. The results of the analysis show how important the global capabilities of logistics companies are, especially the increasing importance of logistics activities for countries. For this reason, logistics companies operating on an international scale need to attach importance to the competitive intensity and develop their marketing and sales capabilities. Originality/value: The research is original in that it examines the global capabilities of logistics companies in their international activities and the effects of competition intensity. In addition, it is important for companies in this sector to examine the effects of marketing and sales capabilities so that logistics companies can reach more customers in their international activities and be more effective in the market compared to their competitors
Evaluation of the sella morphology in chiari malformation type ı
No full textAIM: To investigate the morphology of sella turcica (ST) in Chiari malformation type I (CM-I) using computed tomography. MATERIAL and METHODS: The size and shape of ST were examined using the radiological images of 32 CM-I patients (21 female/11 male, mean age: 26.09 ± 15.39 years), and 32 normal participants (19 female/13 male, mean age: 28.56 ± 19.37 years). RESULTS: The height, diameter, width, and length of ST were similar in CM-I and control groups (p>0.05). According to the Axelsson classification, the ST shape in CM-I was identified as normal in 16 patients (50%), oblique anterior wall in 2 patients (6.25%), irregularity in 6 patients (18.75%), and pyramidal shape of the dorsum sellae in 8 patients (25%). In controls, the ST shape was identified as normal in 18 patients (56.25%), oblique anterior wall in 4 patients (12.50%), irregularity in 2 patients (6.25%), and pyramidal shape of the dorsum sellae in 8 patients (25%). According to the Camp classification, the ST shape in CM-I was identified as oval in 6 patients (18.80%), round in 21 patients (65.60%), and flattened in 5 patients (15.60%). In controls, the ST shape was identified as oval in 19 subjects (59.40%), round in 10 patients (31.30%), and flattened in 3 patients (9.40%). CONCLUSION: The size of ST in patients with CM-I was similar to that in healthy partcipants. The only difference in ST morphology was that patients with CM-I had more round-shaped sella, whereas normal subjects had more oval-shaped sella
A novel fuzzy decision-making approach to pension fund investments in renewable energy
No full textPension fund must consider some significant issues when making renewable energy project investment decisions. It is necessary to determine the most important factors and prioritize the indicators. Accordingly, the purpose of this study is to conduct a priority analysis of the determinants of investment in renewable energy projects by pension funds. This study constructs a novel fuzzy decision-making model. First, five indicators for this process are weighted using an entropy methodology based on sine trigonometric Pythagorean fuzzy sets. The CRITIC methodology is also considered to make a comparative evaluation. Second, five different clean energy investment alternatives for pension funds are ranked using the RATGOS methodology. Similarly, this ranking analysis is also made by considering TOPSIS technique to check the reliability of the results. The main contribution of this study is the creation of a new and comprehensive fuzzy decision-making model to identify the most important factors in renewable energy project investments for pension funds. The proposed model uses the RATGOS technique to rank clean energy investment alternatives for pension funds. By considering the geometrical mean in the RATGOS calculation process, criticisms related to existing ranking techniques can be overcome. The use of sine trigonometric Pythagorean fuzzy numbers provides significant benefits to the quality of the proposed decision-making model. The defuzzification process can be implemented appropriately using these sets. Therefore, this study’s findings pave the way for investors to make investment decisions under these circumstances. It is concluded that the most important criterion is risk minimization. Effective regulations are another critical issue. Furthermore, the ranking results indicate that the most suitable renewable energy alternative is green bonds. The comparative results with STPFY-TOPSIS show that the proposed model generates coherent and reliable findings
Is hotel revenue performance effective for destination competitiveness? an assessment by wavelet coherence analysis
No full textHotel industry is crucial for destination competitiveness as part of quality tourist infrastructure. The high performance of the industry promises a positive effect on destination competitive. This study aims to develop a approach focusing on the hotel revenue-related performance data in the case of European cities (Istanbul, London, Madrid, Paris, and Rome). Wavelet coherence analysis was applied on revenue data of the years 2013–2022 from 4000+ hotels. Findings reveal time–frequency relationships between hotel revenue variables, highlighting consistent coherence in supply–demand relationships during the pandemic, except for Rome. Furthermore, the analysis detected differentiated patterns in supply–revenue coherence, with Istanbul’s market showing unique fluctuations. London is the city with higher revenue expertise. Key revenue performance indicators of hotels emerged as significant determinants of a city’s competitiveness. These insights present implications for policymakers, community stakeholders, and industry practitioners, emphasizing the pivotal role of adept revenue professionals in improving competitiveness in their destinations
Intracavernosal mesenchymal stem cell therapy in ischaemic priapism: an experimental study
No full textIntroduction: The most common form of priapism is ischaemic and its prevalence in men has increased in recent years as a result of intracavernosal drug use. Currently, there is no approved specific treatment for ischaemic priapism other than cavernosal aspiration, which can only provide detumescence. This study aims to evaluate the efficacy of intracavernosal mesenchymal stem cell (MSC) therapy in an ischaemic priapism model. Material and methods: Thirty male Wistar albino rats were divided into three groups: sham (n = 6), priapism (n = 12) and priapism + MSC treatment (n = 12). The experimental groups were also divided into 1 and 12 h subgroups of ischaemic priapism. The experimental model was created using a vacuum erection device and constrictive tape technique, and intracavernosal MSC were applied immediately after the tape was removed. After 4 weeks, intracavernosal pressures (ICPs) and systemic mean arterial pressure (MAP) were measured. Penectomy was then performed to assess histopathological and molecular changes in the rats’ penile tissues. Results: In the ischaemic priapism model, MSC therapy showed significant improvements in peak and mean ICPs and mean ICP/MAP ratio. Histopathological analysis showed significant increases in smooth-muscle/collagen ratio and e-NOS and n-NOS expression. Although there was a decrease in fibrosis, it was not significant. At the molecular level, there were significant decreases in TGF-beta and VEGF mRNA expression, whilst NGF and BDNF mRNA-expression levels showed significant increases with MSC therapy. In terms of ICPs, the therapy showed more significant improvements in short-term priapism. However, when looking at histopathological and molecular parameters, the therapy had positive effects on a wider range of parameters in the long-term priapism. Conclusion: MSC treatment improved cavernosal physiology and had positive effects at the histopathological and molecular level in the ischaemic priapism model