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Exploring the lacrimal sac fossa: anatomical insights for optimizing external dacryocystorhinostomy
No full textBackgroundExternal dacryocystorhinostomy is considered the gold standard for treating epiphora resulting from nasolacrimal duct obstruction. Despite the success of the procedure, a visible facial skin scar often undermines the surgical outcome. The aim of this study is to prevent visible facial scarring following oculoplastic interventions by improving the insight into the anatomical details of the lacrimal sac fossa (LSF), lacrimo-maxillary suture (LMS), periosteum, and lacrimal diaphragm.MethodsThe study examined the medial canthal region of eighty adult male sspecimens to investigate the landmarks associated with the LSF. The periorbital area was dissected to reveal the skin, subcutaneous tissues, orbicularis oculi muscles, and the lacrimal drainage system, all of which were detached from their bony attachments. The lengths of the lacrimal crests, midline length, midline width, dorsolateral angle, composition of the LMS, and area of the LSF were evaluated using the ImageJ program. The LSF was categorized into six distinct shapes: ellipsoid, oval, inverted pear, straight pear, oblique hammer, and quadrangular.ResultsThe measurements of the anterior lacrimal crest averaged 2.2 +/- 0.4 cm, the posterior edge 2.0 +/- 0.4 cm, and the midline 1.9 +/- 0.3 cm. The area of the LSF was found to be 1.4 +/- 0.5 cm(2). The analysis reveals that about half of the LSF consists of equal parts maxillary and lacrimal bones. The dorsolateral angle values where the maxilla and os lacrimale equally contributed to the structure of the LSF were higher than those completely formed by the maxilla. The shapes of the LSF were classified as ellipsoid (35%), oblique hammer (21.3%), oval (13.7%), inverted pear (15%), with the ellipsoid type being the most frequent. The anterior lacrimal crest length of the oval-shaped LSF was shorter than that of the oblique hammer-shaped LSF. Similarly, the posterior lacrimal crest of the oval-shaped LSF was shorter than that of the oblique hammer-shaped LSF. The midline length of ellipsoid, oval, and inverted pear-shaped LSFs was shorter than that of oblique hammer-shaped LSFs.ConclusionThe length of anterior lacrimal crest and LMS are suggested as the most reliable navigational references for locating the type of LSF. Mastery of the transversal and vertical orientation of the LSF is essential for surgeons performing oculoplastic surgeries tailored to individual anatomical variations. This study is clinically valuable as it underscores the necessity for oculoplastic surgeons to adapt surgical techniques in response to anatomical differences encountered during surgery
Boundary value problems for bi-polyanalytic functions on the upper half plane
No full textIn this study, explicit solutions for certain boundary value problems in the upper half-plane are obtained. Various types of boundary conditions are examined in detail, and their effects on the solutions are analyzed. The solution methodology relies on higher-order Cauchy-Pompeiu representations, which are used to address boundary value problems for bi-polyanalytic functions and inhomogeneous Cauchy-Riemann equations. In this context, the solutions obtained extend classical boundary value problems, including the Schwarz, Dirichlet and Neumann problems, providing a more general framework for analyzing these equations
Classification of radiographic and non-radiographic axial spondylarthritis in pelvic radiography using deep convolution neural network models
No full textDiscriminating radiographic axial spondyloarthritis (r-axSpA) from nonradiographic axial spondyloarthritis (nr-axSpA) using pelvic radiographs is challenging, especially for inexperienced clinicians. This study aims to perform deep convolution neuronal network (CNN) models to aid in this diagnostic challenge by using their radiographs. Six-hundred sacroiliac joint exams (300 pelvic radiographs) of patients from axSpA cohort were enrolled (screened between Jan 2010 and Jan 2020). All radiographs were examined and graded by a blinded expert rheumatologist. Four CNN models (VGG16, ResNet, DenseNet, and MobileNet) were proposed by combining them with the YOLOv7 object detection algorithm to mark the sacroiliac joints. The classification results of CNNs were evaluated by performance metrics [accuracy, AUROC (area under the receiver operating characteristic curve)]. The VGG16 model with the YOLOv7 algorithm yielded the best performance [accuracy of 83.8% (95% CI; 73.3–92.9%)]. The accuracy values of other models were 70.7% (58.3–82.7%), 77.1% (65.1–87.3%), and 71.8% (59.0-83.1%) for ResNet, DenseNet, and MobileNet, respectively. In the ROC analysis, the AUC value of the VGG16 model (AUC = 0.882) was higher than other CNNs (AUCs = 0.836, 0.808, and 0.787; DenseNet, ResNet, and MobileNet, respectively). This paper revealed deep learning architectures were able to differentiate r-axSpA from nr-axSpA on pelvic radiographs. Hereby, these models might be used as a clinical decision support system in clinical practice. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024
Optical performance and luminescence properties of Dy3+-doped LaMgB5O10 phosphors
No full textDespite significant advancements in borate-based phosphors, improving luminescent efficiency and thermal stability, particularly at high temperatures, remains a persistent challenge. In this study, Dy3+-doped LaMgB5O10 (LMBO) phosphors were synthesized and characterized for their photoluminescent properties to address these issues. Under 344 nm excitation, the Dy3+-activated LMBO phosphors exhibited strong luminescence with characteristic peaks at 482 nm (blue), 578 nm (yellow), and 663 nm (red), corresponding to specific Dy3+ transitions. Optimal luminescence was achieved at a doping level of 2 wt% Dy3+, beyond which quenching effects reduced emission intensity. The critical quenching distance (Rc) was estimated at 24.66 & Aring;, indicating predominant non-radiative energy transfer. Moreover, thermal quenching was reduced, with the activation energy for thermal quenching determined to be 0.1975 eV, demonstrating that the material can maintain reasonable luminescence efficiency at elevated temperatures. Time-resolved photoluminescence spectroscopy revealed multi-exponential decay behavior, indicating the presence of multiple decay processes. The average luminescence lifetimes were calculated as 632 mu s for the 2 wt% Dy3+ sample and 539 mu s for the 3 wt% Dy3+ sample, with a clear concentration quenching effect observed at higher dopant levels. Colorimetric analysis in the CIE 1931 color space revealed a shift toward yellow with increasing Dy3+ concentration, achieving a correlated color temperature (CCT) of 6595 K at 2 wt% Dy3+. This shift supports the material's potential for photonic and lighting applications. These findings highlight a significant advancement in addressing the thermal stability issue in phosphor materials, making Dy3+-doped LMBO phosphors promising candidates for advanced photonic technologies.Deanship of Graduate Studies and Scientific Research, Jazan University, Saudi Arabia [RG24-M06]The authors gratefully acknowledge the funding of the Deanship of Graduate Studies and Scientific Research, Jazan University, Saudi Arabia, through Project Number: RG24-M06
A digital maturity assessment from annual activity reports in higher education institutions
No full textA total Digital Transformation (DT) in Higher Education Institutions (HEIs) requires eliminating the digital gaps between institutions and creating and implementing well-designed DT road maps. To create successful digital road maps, it is necessary to assess the current digitalization levels of HEIs in detail. This assessment would help universities understand a) where they are currently in DT, b) what are their strengths and weaknesses, c) how to determine development areas, and d) how they can support better decisions on all issues related to their DT. In this context, the aim of this study is twofold. First, develop a methodology to assess the DM level of HEIs and rank them. Second, based on assessment and analysis, identify development areas for their DT advantages. One of the most important obstacles to the assessment of DT is that HEIs do not have the data and metrics to use in the measurement of DT. For this reason, this study uses the annual activity reports of universities as a data source. This also allows researchers to compare different universities with each other to make comparisons between universities and assess their relative strengths and weaknesses. Annual activity reports from 24 universities are analyzed with a textmining approach. The results are expected to contribute to both the relevant literature and practitioners. Moreover, this study is expected to form a basis for HEIs to determine successful holistic DT strategies so that they can both train the workforce of the future and position themselves strategically as institutions that offer quality and competitive education. © 2025 Nova Science Publishers, Inc. All rights reserved
Effect of surface coatings on endothelialization and biofilm in PTFE vascular grafts
No full textPolytetrafluoroethylene (PTFE) grafts are of great importance for vascular surgery and many methods have been developed to improve their biocompatibility. The most important of these methods is the coating of the inner surfaces of the grafts. In this study, the effects of surface coatings used in vascular grafts on endothelialization and bacterial biofilm formation were investigated. Three different PTFE graft types, heparin coated, carbon coated and uncoated, were compared. HUVEC cell culture was used for endothelialization experiments and Staphylococcus aureus strain was used for biofilm formation. Endothelialization was evaluated by inverted microscopy and scanning electron microscopy (SEM). Heparin-coated grafts showed more biofilm formation than other graft types (p < 0.01). Moderate biofilm formation was observed in carbon-coated grafts (p < 0.05). When evaluating endothelialization, heparin-coated grafts showed more cell adhesion in the first days, but lagged behind the other graft types in the following days. Carbon-coated grafts showed more endothelial cell proliferation in the long term. While biofilm formation was high in heparin-coated grafts, carbon-coated grafts provided better endothelialization. Our study showed that the coating of PTFE grafts significantly affects biocompatibility and infection risk.Research Fund of the Aydimath;n Adnan Menderes University; Ege University Application and Research Center For Testing and AnalysisThe authors would like to acknowledge Ege University Application and Research Center For Testing and Analysis (EGE MATAL) for the SEM imaging
Forecasting urban shifts post-earthquake: LULC change analysis in Elazığ, Turkey using ANN and Markov models
No full textUnderstanding land use and land cover (LULC) dynamics in seismically active regions is crucial for risk-informed urban planning and sustainable post-disaster recovery. This study investigates the impact of the Mw 6.8 Elaz & imath;& gbreve; earthquake (24 January 2020) on LULC patterns in eastern Turkey by integrating high-resolution Sentinel-2 satellite imagery with geographic information systems (GIS), remote sensing (RS), artificial neural networks (ANNs), and Markov chain modelling. The methodology comprises four phases: establishing a pre-earthquake baseline (2015-2019), assessing post-earthquake changes (2015-2023), analysing transition probabilities to identify key LULC drivers, and forecasting land-use scenarios for 2030 and 2050 under seismic and non-seismic conditions. Results reveal that seismic activity significantly accelerates urban expansion, shifting development towards geologically stable zones. By 2050, artificial surfaces are projected to occupy 54.70% of the region under seismic influence, compared to 48.87% without it. Agricultural land is more preserved in the seismic scenario (26.54%) than in the non-seismic case (22.68%), while pasture and meadow areas decline sharply to 6.18%, raising concerns for biodiversity and ecosystem services. These findings emphasise the importance of integrating ecological considerations and seismic risk into land-use planning frameworks. By combining multicriteria decision-making with machine learning-based forecasting, the study offers a replicable and scalable model for balancing urban growth, environmental conservation, and resilience. Framed within interdisciplinary insights from disaster resilience theory, urban governance, and spatial risk modelling, this research contributes to the global discourse on sustainable urban transformation in the face of increasing natural hazards
Gender-specific foot morphology and biomechanical patterns in young adults: a combined photogrammetric and plantar pressure analysis
No full textPurpose Understanding gender-based foot morphological differences is critical for ergonomic footwear design. This study investigated these variations in young adults using photogrammetric and plantar pressure analysis. Methods We analyzed 200 healthy participants (100 males, 100 females; aged 19-21 years) through digital photogrammetry and RSscan Footscan pressure mapping. Key parameters included foot length (FL), ball width (BWF), hallux valgus angle (HVd), lateral foot angle (LdF), and Clarke's Index for arch classification. Plantar pressure distribution was assessed across 10 anatomical zones. ResultsWe revealed significant gender disparities: males had longer (26.6 vs. 25.2 cm) and wider feet (10.2 vs. 9.1 cm), while 75% of participants exhibited HVd (5.1 degrees-6.3 degrees), with no gender difference. Dynamic Clarke's Index showed 80% had high arches, correlating with lower BMI (p < 0.001). Pressure analysis highlighted higher midfoot loading (37.8-41.2 cm2) and medial forefoot pressure in HVd cases. Females predominantly wore smaller shoes (sizes 36-38), whereas 89% of males wore sizes 42-44. BMI influenced midfoot pressure (r = 0.3) and arch height, with flat arches linked to higher BMI. Foot asymmetry (38%) and HVd prevalence underscored the need for gender-specific shoe designs. ConclusionIt emphasize prioritizing ergonomic footwear to mitigate pressure imbalances, HVd progression, and asymmetry, particularly in high-BMI individuals. This dual-method approach provides actionable insights for biomechanical applications and footwear customization
Evaluating the impact of altitudinal variations on COVID-19 mortality rates: a comprehensive analysis
No full textBackground High altitude, known for its effects on respiratory diseases, was analyzed for its potential protective role. Data from the New York Times COVID-19 repository, U.S. Census Bureau, and topographic maps were utilized, covering January 2020 to August 2022, including pre- and post-vaccination periods. This study investigates the influence of high altitude on COVID-19 mortality, fatality rates, and vaccination outcomes in the United States. COVID-19, caused by SARS-CoV-2, has shown significant disparities in severity and outcomes across populations. Methods This study utilized publicly available data from the New York Times COVID-19 repository and the US Census Bureau's American Community Survey to analyze case fatality rates across mainland US counties from January 21, 2020, to August 13, 2022. Average altitude data were obtained from topographic maps, and counties outside the mainland USA were excluded. Vaccination-related data were assessed using the cutoff date of December 14, 2020. The rural-urban status of counties was determined using the Index of Relative Rurality (IRR) from Waldorf and Kim's study, which included 3105 of 3109 counties. Results Counties above 1500 m exhibited significantly lower case numbers, deaths, cases per million, and fatality rates compared to counties below this altitude. Pre-vaccination fatality rates were notably reduced in high-altitude regions (p = 0.0001), while post-vaccination data continued to demonstrate lower fatality rates (p < 0.0001). A positive correlation between rurality and post-vaccination fatality rates was observed (rho = 0.176, p = 0.0001). Altitude, alongside vaccination status, was identified as a critical factor influencing fatality rates (p = 0.001 for both). Additionally, a significant positive correlation between rurality (Index of Relative Rurality) and post-vaccination fatality rates was observed (rho = 0.176, p = 0.0001). Conclusions Our findings highlight that high-altitude adaptations, such as increased lung capacity and epigenetic changes, may mitigate COVID-19 severity. However, the role of environmental and genetic factors remains insufficiently explored. Importantly, the study underscores healthcare inequities in rural high-altitude areas, where limited vaccination access exacerbates mortality risks. While altitude shows promise as a protective factor, addressing healthcare access disparities and further investigating high-altitude physiological and genetic adaptations are imperative for optimizing COVID-19 outcomes in diverse populations
Evaluation of measurement uncertainty of coagulation parameters according to two different current guidelines
No full textObjectives: This study aims to calculate the measurement uncertainty values of prothrombin time (PT), activated partial thromboplastin time (APTT), D-dimer, and fibrinogen tests according to ISO/TS 20914 and Nordtest 2017 guidelines and to compare these values with the total allowable error (TEa%) and maximum expanded allowable measurement uncertainty (MAU) values established by international organizations. Methods: Normal and pathological level internal quality control data for PT, APTT, D-dimer, and fibrinogen tests performed on the Sysmex CS2100 device between January and May 2024 were obtained from the Laboratory Information System. External quality control data for October 2023 and September 2024 were sourced from the external quality control system. Measurement uncertainty was calculated following ISO/TS 20914 and Nordtest 2017 guidelines. Results: According to the ISO/TS 20914 guideline, the measurement uncertainty values for PT, APTT, D-dimer, and fibrinogen tests were 10.42%, 3.49%, 4.81%, and 19.10%, respectively. According to the Nordtest guideline, the measurement uncertainty values were 10.44%, 12.64%, 17.94%, and 21.69%, respectively. Conclusion: Based on the ISO/TS 20914 guideline, it was observed that the measurement uncertainty values for all coagulation tests met the TEa% analytical targets. According to the Nordtest guideline, all tests except fibrinogen met these targets. When evaluated against the MAU criterion, it was determined that D-dimer met the targeted quality specification according to both guidelines; however, the measurement uncertainty values for PT, APTT, and fibrinogen exceeded the allowed targets. Standardization of the measurement uncertainty calculation model and the determination of analytical targets based on laboratory priorities can ensure reliable monitoring of analytical performance. © 2025, Association of Clinical Biochemistry Specialists (Klinik Biyokimya Uzmanlari Dernegi). All rights reserved