Search Results (1,237)

Background: In clinical practice, visual outcomes with anti-VEGF therapy may be worse than those observed in clinical trials. In this study, we aim to investigate the long-term outcomes of neovascularization treated with intravitreal aflibercept injections (IAI) in a teaching hospital setting. Methods: This is a retrospective, single-center study including 81 nAMD patients (116 eyes), those both newly diagnosed and switched from ranibizumab. All patients had a follow-up duration of at least seven years. Treatment involved three monthly injections followed by either a pro re nata (PRN) or treat and extend regimen. Follow-up care was primarily conducted by training physicians. The primary endpoint was the change in best-corrected visual acuity (BCVA) over seven years. Secondary endpoints included central retinal thickness changes, qualitative OCT parameters, macular atrophy progression, injection frequency, and treatment adherence. Results: Among the 116 eyes, 52 (44.8%) completed the seven-year follow-up. Visual acuity improved by +2.1 letters in the overall population (+6.3 letters in treatment-naive eyes) after the loading phase but gradually declined, resulting in a loss of −12.3 letters at seven years. BCVA remained stable (a loss of fewer than 15 letters) in 57.7% of eyes. Central retinal thickness (CRT) decreased significantly during follow-up in both naive and switcher eyes. Macular atrophy occurred in 94.2% of eyes, progressing from 1.42 mm² to 8.55 mm² over seven years (p < 0.001). The mean number of injections was 4.1 ± 1.8 during the first year and 3.7 per year thereafter. Advanced age at diagnosis was a risk factor for loss to follow-up, with bilaterality being a protective factor against loss to follow-up (p < 0.05). Conclusions: This study highlights the challenges faced by a retina clinic in a teaching hospital. Suboptimal functional and anatomical outcomes in real life may derive from insufficient patient information and inconsistent monitoring, which contributes to undertreatment and affects long-term visual outcomes. It also raises concerns about supervision in a teaching hospital which needs to be improved. Full article

Traffic-related pollutants remain a challenging global issue, with significant policy implications. Within the European Union, Romania has the highest yearly societal cost per capita due to air pollution, which kills 29,000 Romanians every year, whereas the health and economic costs are also significant. In this context, municipal authorities in the country, particularly in high-density areas, should place a strong focus on mitigating air pollution. In particular, the capital city, Bucharest, ranks among the most congested cities in the world while registering the highest pollution index in Romania, with traffic pollution responsible for two-thirds of its air pollution. Consequently, studies that assess and model pollution trends are paramount to inform local policy-making processes and assist pollution-mitigation efforts. In this paper, a generalized additive modeling (GAM) framework is employed to model hourly concentrations of nitrogen dioxide (NO₂), i.e., a relevant traffic-pollution proxy, at a busy urban traffic location in central Bucharest, Romania. All models are developed on a wide, fine-granularity dataset spanning January 2017–December 2022 and include extensive meteorological covariates. Model robustness is assured by switching between the generalized additive model (GAM) framework and the generalized additive mixed model (GAMM) framework when the residual autoregressive process needs to be specifically acknowledged. Results indicate that trend GAMs explain a large amount of the hourly variation in traffic pollution. Furthermore, meteorological factors contribute to increasing the models’ explanation power, with wind direction, relative humidity, and the interaction between wind speed and the atmospheric pressure emerging as important mitigators for NO₂ concentrations in Bucharest. The results of this study can be valuable in assisting local authorities to take proactive measures for traffic pollution control in the capital city of Romania. Full article

Background and Objectives: Long-acting cabotegravir and rilpivirine (LA-CAB/RPV) offers an alternative to daily oral antiretroviral therapy (ART) for people living with HIV (PLWH). Although LA-CAB/RPV has been approved in Turkey, the country remains in the pre-rollout period, and national data on patient perspectives are lacking. This is the first nationwide study from Turkey, a setting of increasing HIV incidence, assessing PLWH perspectives on switching to LA-CAB/RPV and the influence of motivational factors on treatment preferences. Materials and Methods: A prospective, multicenter, cross-sectional study was conducted across 11 HIV treatment centers representing all regions of Turkey. Virologically suppressed PLWH meeting current eligibility criteria for LA-CAB/RPV were included. Treatment preferences (switch to LA-CAB/RPV or remain on oral ART) and five anticipated motivational domains, namely perceived efficacy, safety, convenience, privacy, and cost, were systematically assessed through structured, face-to-face interviews. Results: Among 200 eligible participants, 86% (n = 172) preferred switching to LA-CAB/RPV. In all subgroups, LA-CAB/RPV was preferred over oral ART, except for those with no formal literacy. Prior awareness of LA-CAB/RPV was significantly associated with the switching preference (p < 0.001), with healthcare providers being the most common source of information, at 45.5% (n = 172) (p < 0.001). Residential proximity to the healthcare center (p = 0.018) and all motivational factors significantly influenced the preference (p < 0.05). Notably, when participants who initially chose to remain on oral ART were asked whether they would reconsider switching if injections were administered every six months, overall preference for long-acting therapy increased from 86% to 98%. Conclusions: High clinical eligibility and strong acceptability for LA-CAB/RPV were observed among Turkish PLWH. Our findings demonstrate that structured motivational factors significantly influence the treatment preference. Addressing these patient-centered factors and logistical barriers may support the successful integration of long-acting therapies into routine HIV care. Future longer-interval agents may improve patient-centered acceptability. Full article

Background: Understanding the duration and quality of immune memory following SARS-CoV-2 infection and vaccination is critical for informing public health strategies and vaccine development. While waning antibody levels have raised concerns about long-term protection, the persistence of memory B cells (MBCs) and T cells plays a vital role in sustaining immunity. Materials and Methods: We conducted a longitudinal prospective study over 12 months, enrolling 285 participants in total, either after natural infection or vaccination with BNT162b2 or mRNA-1273. Peripheral blood samples were collected at four defined time points (baseline, 1–2 months, 6–7 months, and 12–13 months after vaccination or disease onset). Immune responses were assessed through serological assays quantifying anti-RBD IgG and neutralizing antibodies, B-ELISPOT, and multiparameter flow cytometry for S1-specific memory B cells. Results: Both mRNA vaccines induced robust B cell and antibody responses, exceeding those observed after natural infection. Memory B cell frequencies peaked at 6 months and declined by 12 months, but remained above the baseline. The mRNA-1273 vaccine elicited stronger and more durable humoral and memory B-cell-mediated immunity compared to BNT162b2, likely influenced by its higher mRNA dose and longer prime-boost interval. Class-switched memory B cells and S1-specific B cells were significantly expanded in vaccine recipients. Natural infection induced more heterogeneous immune memory. Conclusions: Both mRNA vaccination and natural SARS-CoV-2 infection induce a comparable expansion of memory B cell subsets, reflecting a consistent pattern of humoral immune responses across all studied groups. These findings highlight the importance of vaccination in generating sustained immunological memory and suggest that the vaccine platform and dosage influence the magnitude and durability of immune responses against SARS-CoV-2. Full article

This study investigates whether audit tenure mandates—designed to curb managerial discretion—may unintentionally enable disguised opinion shopping. Specifically, it examines whether firms benefit from observed mandates that align with their unobservable preferences, despite appearing to comply with mandatory audit firm rotation or retention rules. A counterfactual framework is developed to estimate firms’ preference for switching or retention in the absence of regulation, allowing identification of strategic alignment under constraint. Empirical analysis using Korean data from 2000 to 2009 reveals that firms classified as disguised opinion shoppers are more likely to receive unmodified audit opinions and exhibit lower audit quality, as indicated by higher discretionary accruals and more frequent reporting irregularities. These effects are concentrated under mandatory retention and not observed under rotation, suggesting that forced auditor turnover weakens firms’ ability to secure favorable outcomes. Additional evidence shows that these firms are more likely to retain the same auditor after mandates expire, consistent with a reward-for-accommodation mechanism. Thus, this study not only provides empirical evidence that opinion shopping can persist under auditor tenure mandates, but also introduces a novel method for identifying such behavior when traditional signals—such as voluntary dismissals—are unavailable. These findings inform ongoing regulatory debates on the effectiveness of tenure-based reforms. Full article

Relaxation behavior of water confined in reverse micelles under temperature-induced micelle clustering is undertaken using broadband dielectric spectroscopy in frequency range 1 Hz–20 GHz. All microemulsion systems with sufficiently noticeable micelle water pool (water/surfactant molar ratio W > 10) depict three relaxation processes, in low, high and microwave frequencies, anchoring with relaxation of shell (bound) water, orientation of surfactant anions at water-surfactant interface and relaxation of bulk water confined in reverse micelles. The analysis of dielectric relaxation processes in AOT-based w/o microemulsions under temperature induced clustering of reverse micelles were made according to structural information obtained in NMR and conductometry experiments. The “wait and switch” relaxation mechanism was applied for the explanation of results for water in the bound and bulk states under spatial limitation in reverse micelles. It was shown that surfactant layer predominantly influences the bound water. The properties of water close to AOT interface are determined by strong interactions between water and ionic AOT molecules, which perturb water H-bonding network. The decrease in micelle size causes a weakening of hydrogen bonds, deformation of its steric network and reduction in co-operative relaxation effects. Full article

Memristors with resistive switching capabilities are vital for information storage and brain-inspired computing, making them a key focus in current research. This study demonstrates non-volatile analog resistive switching behavior in Al/TiO_x/TiN/Si(n⁺⁺)/Al memristive devices. Analog resistive switching offers gradual, controllable conductance changes, which are essential for mimicking brain-like synaptic behavior, unlike digital/abrupt switching. The amorphous titanium oxide (TiO_x) active layer was deposited using the pulsed-DC reactive magnetron sputtering technique. The impact of increasing the oxide thickness on the electrical performance of the memristors was investigated. Electrical characterizations revealed stable, forming-free analog resistive switching, achieving endurance beyond 300 DC cycles. The charge conduction mechanisms underlying the current–voltage (I–V) characteristics are analyzed in detail, revealing the presence of ohmic behavior, Schottky emission, and space-charge-limited conduction (SCLC). Experimental results indicate that increasing the TiO_x film thickness from 31 to 44 nm leads to a notable change in the current conduction mechanism. The results confirm that the memristors have good stability (>1500 s) and are capable of exhibiting excellent long-term potentiation (LTP) and long-term depression (LTD) properties. The analog switching driven by oxygen vacancy-induced barrier modulation in the TiO_x/TiN interface is explained in detail, supported by a proposed model. The remarkable switching characteristics exhibited by the TiO_x-based memristive devices make them highly suitable for artificial synapse applications in neuromorphic computing systems. Full article

This study investigates whether internationally diversified firms substitute between accrual-based and real earnings management and examines how institutional supervision moderates this relationship. Drawing on a sample of Taiwanese firms listed on the Taiwan Stock Exchange from 2003 to 2016, we conduct regression analyses to test our hypothesis. We find that internationally diversified firms actively shift between accrual and real earnings management strategies depending on the constraints they face. Specifically, firms tend to rely more on accrual-based manipulation when information asymmetry is high and switch to real earnings management when accruals are more easily detected. We also show that stronger institutional supervision—measured by information transparency and investor protection—significantly curbs accrual-based earnings management. These findings reflect the higher volatility and agency problems associated with international operations, such as exposure to foreign risks and the distance between parent and subsidiary firms. By highlighting the conditions under which firms manage earnings and the supervisory mechanisms that constrain such behavior, this study offers practical insights for managers seeking to smooth earnings, investors aiming to evaluate firm transparency, and policymakers designing regulations to deter opportunistic financial reporting. Full article

This paper provides a reliability analysis of selected components in the electrical power supply systems used for railway traffic control equipment. It includes rectifiers, controllers, inverters, generators, batteries, sensors, and switching elements. The study used failure data from power supply system elements on selected railway lines. The analysis was performed using a mathematical model based on Markov processes. Based on the findings, recommendations were made to improve safety levels. The results presented in the paper could serve as a valuable source of information for operators of power supply systems in railway traffic control, helping them optimize maintenance processes and increase equipment reliability. Full article

This study examines how Chinese EFL learners behave in peer interactions by negotiating meaning through communication strategies. This is a small-scale study with both quantitative and qualitative analysis. Sixteen Chinese EFL students and one native English teacher were observed in an intensive English program. The students were asked to interact with their peers in a decision-making task and an information-gap task. Video-recorded data were collected, transcribed and analyzed. The results showed that negotiation occur more frequently in information-gap tasks than decision-making tasks and students primarily employed confirmation checks. For communication strategies used to negotiate, direct strategies were employed most frequently, in which students mainly used code-switch and mime. Indirect strategies followed, with repetition occurring as the most frequently employed strategy. Interactional strategies, including co-construction and appeal for help, were less frequently used. The findings highlight the influence of cultural factors and students’ motivation on their behaviors. Full article

Accurate and automated detection and tracking of cells in microscopy images is a persistent challenge in biotechnology and biomedical research. Effective detection and tracking are crucial for understanding biological processes and extracting meaningful data for subsequent simulations. In this study, we present an integrated pipeline that leverages a fine-tuned YOLOv8x model for detecting cells and cell divisions across microscopy image series. While YOLOv8x exhibits strong detection capabilities, it occasionally misses certain cells, leading to gaps in data. To mitigate this, we incorporate the DeepSORT tracking algorithm, which enhances data association and reduces the cells’ identity (ID) switches by utilizing a pre-trained convolutional network for robust multi-object tracking. This combination ensures continuous detection and compensates for missed detections, thereby improving overall recall. Our approach achieves a recall of 93.21% with the enhanced DeepSORT algorithm, compared to the 53.47% recall obtained by the original YOLOv8x model. The proposed pipeline effectively extracts detailed information from structured image datasets, providing a reliable approximation of cellular processes in culture environments. Full article

This research paper presents a comprehensive comparison between Permanent Magnet Synchronous Motors (PMSMs) and Switched Reluctance Motors (SRMs) in the context of drone applications. The study focuses on motors designed for an output power of 500 watts, with a torque of 0.8 Nm. Simulation results demonstrate that both motor types achieve the specified power rating, exhibiting a torque output of 0.8 Nm. In this comparative analysis, key performance parameters, efficiency, and operational characteristics of PMSM and SRM are systematically evaluated. The study addresses the unique features and challenges associated with each motor type, providing valuable insights for optimizing drone propulsion systems. Additionally, the influence of these motor choices on drone efficiency, weight, and overall performance is discussed. The research contributes to the understanding of motor selection in drone design, offering practical guidance for engineers and researchers involved in unmanned aerial vehicle development. As drone applications continue to diversify, this comparative study aids in making informed decisions regarding motor technologies, balancing power requirements, and maximizing operational efficiency. Full article

High efficiency and high power density are key targets in modern power conversion. Operating power converters at high switching frequencies enables the use of smaller passive components, which, in turn, facilitate achieving high power density. However, the concurrent increase in switching frequency and power density leads to efficiency and overheating issues. Soft switching techniques are typically employed to minimize switching losses and significantly improve efficiency by reducing power losses. However, the hysteresis behavior of the power electronics devices’ output capacitance, C_OSS, is the cause of regrettable losses in Super-Junction (SJ) MOSFETs, SiC MOSFETs, and GaN HEMTs, which are usually adopted in soft switching-based conversion schemes. This paper reviews the techniques for measuring hysteresis traces and power losses, as well as the understanding of the phenomenon to identify current research trends and open problems. A few studies have reported that GaN HEMTs tend to exhibit the lowest hysteresis losses, while Si superjunction (SJ) MOSFETs often show the highest. However, this conclusion cannot be generalized by comparing the results from different works because they are typically made across devices with different (when the information is reported) breakdown voltages, on-state resistances, die sizes, and test conditions. Moreover, some recent investigations using advanced TCAD simulations have demonstrated that newer Si-SJ MOSFETs employing trench-filling epitaxial growth can achieve significantly reduced hysteresis losses. Similarly, while multiple studies confirm that hysteresis losses increase with increasing dv/dt and decreasing temperature, the extent of this dependence varies significantly with device structure and test methodology. This difficulty in obtaining a general conclusion is due to the lack of proper figures of merit that account for hysteresis losses, making it problematic to evaluate the suitability of different devices in resonant converters. This problem highlights the primary current challenge, which is the development of a standard and automated method for characterizing C_OSS hysteresis. Consequently, significant research effort must be invested in addressing this main challenge and the other challenges described in this study to enable power electronics researchers and practitioners to develop resonant converters properly. Full article

This research studies the impact of macroeconomic announcement surprises on daily U.S. Treasury excess returns during the heart of Alan Greenspan’s tenure as Federal Reserve Chair, addressing the possible limitations of standard static regression (SSR) models, which may suffer from omitted variable bias, parameter instability, and poor mis-specification diagnostics. To complement the SSR framework, an automated general-to-specific (Gets) modeling approach, enhanced with modern indicator saturation methods for robustness, is applied to improve empirical model discovery and mitigate potential biases. By progressively reducing an initially broad set of candidate variables, the Gets methodology steers the model toward congruence, dispenses unstable parameters, and seeks to limit information loss while seeking model congruence and precision. The findings, herein, suggest that U.S. Treasury market responses to macroeconomic news shocks exhibited stability for a core set of announcements that reliably influenced excess returns. In contrast to computationally costless standard static models, the automated Gets-based approach enhances parameter precision and provides a more adaptive structure for identifying relevant predictors. These results demonstrate the potential value of incorporating interpretable automated model selection techniques alongside traditional SSR and Markov switching approaches to improve empirical insights into macroeconomic announcement effects on financial markets. Full article

It is well established that different fasting strategies offer a range of benefits and may even serve as potential therapeutic approaches for metabolic diseases. The biological effects of intermittent fasting (IF) are multidimensional, involving the induction of metabolic switching from glucose to fatty acid and ketone utilization, thereby enhancing fat metabolism and improving glucose tolerance and insulin sensitivity. In addition, IF modulates the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis by lowering IGF-1 levels, a change associated with enhanced cellular protection, reduced tumorigenesis, and delayed aging. Moreover, IF modulates key signaling pathways, including mitogen-activated protein kinases, Notch, and nuclear factor kappa B, which collectively contribute to reduced oxidative stress, attenuated inflammation, and hepatoprotection. Although fasting may present certain challenges, it is essential to be adequately informed about its potential benefits and appropriate preparatory strategies before undertaking various fasting protocols. This review summarizes the current knowledge on various IF protocols and periodic short-term fasting (PSTF) lasting more than 24 h and up to 72 h, highlighting the signaling pathways through which these interventions affect metabolic processes. Additionally, it aims to provide a practical guide for the safe preparation for PSTF lasting more than 24 h and up to 72 h. Full article