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Comparative evaluation of different bleaching agents on the color stability, hardness and surface roughness of indirect esthetic restorative materials with different manufacturing methods
Full text linkBackground: To evaluate the effect of various bleaching agents of on color, surface roughness and microhardness of indirect restorative materials with different manufacturing methods.
Methods: A total of 150 disc-shaped specimens (Ø=8 mm, h = 1.5 mm) were fabricated from 3D-printed resin (Saremco print-CROWNTEC, SAREMCO Dental, Switzerland), milled resin (Lava Ultimate; 3 M ESPE, USA), and conventional resin (Enamel Plus HRi; Micerium, Italy) following the manufacturers' instructions (N = 50/group). Color measurements were performed using a spectrophotometer (VITA Easyshade-V; VITA Zahnfabrik, Germany) under standardized lighting conditions. Microhardness was measured using a Micro Vickers Hardness Tester (HMV-G, Shimadzu, Japan) at a load of 300-gf for 15 s. Surface roughness was measured with a contact profilometer (Perthometer M1, Mahr, Germany). After initial color, microhardness, and surface roughness measurements each group was divided into 5 subgroups: control group, 16% carbamide peroxide (Whiteness Perfect), 35% hydrogen peroxide (Whiteness HP Blue), 16% carbamide peroxide (Opalescence PF), and 40% hydrogen peroxide (Opalescence Boost). After bleaching procedure final color, microhardness and surface roughness of specimens were measured. Color change values were analyzed using Kruskal-Wallis tests followed by Mann-Whitney U tests, while microhardness and surface roughness values were analyzed using two-way ANOVA with Tukey-HSD post-hoc tests (p < 0.05).
Results: Significant differences in ΔE00 values were observed among restorative materials within each bleaching agent group, and among bleaching agents within each restorative material group (p 0.05). The milled-resin group showed the highest Vickers hardness, whereas the printed resin group showed the lowest (p < 0.05). Surface roughness was significantly affected by material type and bleaching agent (p < 0.05). Significantly higher surface roughness was observed in the conventional resin group exposed to Whiteness HP Blue agent (p < 0.05).
Conclusions: The type of indirect restorative material and bleaching agent had an impact on color and surface roughness, while bleaching agents did not influence microhardness. This highlights the importance of material selection in clinical practice
Cyclic codes over F2[u, v, w]/hu2 = v2, uv = 0, w2 = wi and its applications
No full textWe investigate linear and cyclic codes over the ring F2[u, v, w]/hu2 = v2, uv = 0, w2 = wi. This is a commutative Frobenius non-chain ring, which, to the best of our knowledge, is studied here for the first time in the literature. We define a homogeneous weight on the ring and, with respect to a Gray map induced by this weight, obtain the optimal Reed-Muller code RM (1, 7). We analyze the algebraic structure of the ring in detail, determine its ideals, and present code constructions together with their Gray images
Trastuzumab Deruxtecan plus Pertuzumab for HER2-Positive Metastatic Breast Cancer
No full textBackground Trastuzumab deruxtecan has shown efficacy in patients with previously treated human epidermal growth factor receptor 2 (HER2)-positive advanced or metastatic breast cancer. The efficacy and safety of trastuzumab deruxtecan in patients with no previous therapy for HER2-positive advanced or metastatic breast cancer are unclear. Methods We conducted a phase 3 trial involving patients with HER2-positive advanced or metastatic breast cancer and no previous chemotherapy or HER2-directed therapy for metastatic disease. Patients were randomly assigned in a 1:1:1 ratio to receive trastuzumab deruxtecan plus pertuzumab; trastuzumab deruxtecan plus placebo; or a taxane, trastuzumab, and pertuzumab (THP). The primary end point was progression-free survival as assessed by blinded independent central review. Secondary end points included objective response, duration of response, and safety. Results For this prespecified interim analysis, data for trastuzumab deruxtecan plus pertuzumab and for THP are reported; data for trastuzumab deruxtecan plus placebo remain blinded until the final analysis of progression-free survival. At the data-cutoff date (February 26, 2025), the median progression-free survival was 40.7 months with trastuzumab deruxtecan plus pertuzumab (383 patients) and 26.9 months with THP (387 patients) (hazard ratio for progression or death, 0.56; 95% confidence interval [CI], 0.44 to 0.71; P<0.00001 [P-value boundary for superiority, 0.00043]). The incidence of a confirmed response was 85.1% with trastuzumab deruxtecan plus pertuzumab and 78.6% with THP (complete responses in 15.1% and 8.5%, respectively), with a median duration of response of 39.2 months and 26.4 months. Safety was consistent with the known profiles of the individual treatments. The incidence of grade 3 or higher adverse events was 63.5% with trastuzumab deruxtecan plus pertuzumab and 62.3% with THP; the most common were neutropenia, hypokalemia, and anemia with trastuzumab deruxtecan plus pertuzumab and neutropenia, leukopenia, and diarrhea with THP. Adjudicated drug-related interstitial lung disease or pneumonitis occurred in 12.1% of patients receiving trastuzumab deruxtecan plus pertuzumab (grade 1 or 2 in 44 patients and grade 5 [death] in 2 patients) and in 1.0% of those receiving THP (all grade 1 or 2). Conclusions Trastuzumab deruxtecan plus pertuzumab led to a significantly lower risk of progression or death than THP when used as first-line treatment for HER2-positive advanced or metastatic breast cancer, with no new safety signals.Funding agency : AstraZeneca, Daiichi Sankyo Company Limited
The Effects of Information Technologies on Youth Access to Education: Educational Purposes and Gender Inequalities
No full textWith the Covid-19 pandemic commencing in March 2020 and the initiation of online education, information technologies have become more popular among young people, thus making education and information retrieval the primary uses of the internet. This motivates us to investigate the probability of young people using the internet for informational purposes, utilizing the Household Information Technology Usage Survey (HITUS) micro-dataset collected by the Turkish Statistical Institute between 2004 and 2021, using Heckman's two-stage probit method. Our findings revealed that males are more likely to use the Internet for educational purposes than females and that young people in urban regions are more likely to engage in online educational activities. Interestingly, larger household sizes reduce the probability of Internet use for educational purposes. We also discovered that Southeastern Anatolia was the least likely to use the Internet for educational purposes during the period studied. Finally, we found that individuals whose household heads have a high school or university degree are more likely to use the Internet for educational purposes
Vampire squid optimization algorithm for energy-efficient intrusion detection in cyber-physical networks
Full text linkIntrusion Detection Systems (IDS) are increasingly challenged by the complexity, dimensionality, and energy demands of modern network environments, where achieving high detection accuracy often comes at the cost of excessive computational overhead. Existing metaheuristic optimizers, though effective in feature selection and parameter tuning, frequently suffer from premature convergence and high evaluation costs, limiting their real-time applicability. To address these limitations, this paper proposes the Vampire Squid Optimization Algorithm (VSOA)—a novel bio-inspired metaheuristic that models the energy-efficient “drift and strike” foraging behavior of deep-sea vampire squids. VSOA introduces three innovations: (1) a dual-phase adaptive search mechanism that dynamically balances global exploration and local exploitation; (2) a bioluminescent threshold control for selective intensification based on contextual fitness; and (3) an energy-aware phase scheduler that minimizes redundant evaluations for computational efficiency. Applied to benchmark IDS datasets (NSL-KDD, UNSW-NB15, and CICIDS2017), VSOA demonstrates consistent superiority over state-of-the-art optimizers such as PSO, GA, Bat, and HFOA, achieving up to 3.8% higher detection accuracy and a 22% reduction in false-positive rate while using fewer fitness evaluations. These findings confirm that VSOA delivers a robust and resource-efficient optimization strategy for next-generation IDS, effectively bridging the gap between detection accuracy and energy-constrained deployment
Spectral biomarker detection for diagnosis of bladder cancer from urine using ATR-FTIR spectroscopy
No full textFunding agency : European Union's Horizon Europe research and innovation programme
Grant Number : 101135175
Meeting Abstract : P-31-019..
Symmetry-Based Structural Optimization of 50 Dutch Buildings: Quantitative Framework for Material and Carbon Reduction
Full text linkArticle number: 3962.Structural symmetry of constructions directly influences material efficiency and construction complexity. This study presents the Symmetry Optimization and Detection for Architecture (SODA) framework for assessing and improving structural symmetry in existing buildings. The system employs computer vision methods for symmetry detection, the Continuous Symmetry Measure (CSM) based on molecular research, and genetic algorithms for optimization. A total of 50 structures of the Netherlands (Dutch) were examined, which encompassed an area of 2.287 million m2, categorized into five distinct groups. It was indicated that average symmetry improvements were observed, with an increase from 68.4% to 82.7%. The average material reductions were observed to be 18.5%, which was accompanied by a reduction in construction time of 19.2%. The total acknowledged cost reductions were recorded at €87.3 million, with a corresponding reduction of 21,450 tons of CO2 emissions. The results of a statistical analysis suggest that a negative correlation exists between building height and optimization potential (R2 = 0.72). The framework illustrates that systematic symmetry optimization yields substantial efficiency enhancements while preserving architectural integrity and code adherence
3D Cardiac MRI Segmentation Using Spatio-Temporal Convolutional Neural Networks with Shape-Aware Loss Functions
No full textThis research proposes a high-precision spatio-temporal deep learning framework for 3D cardiac MRI segmentation, integrating dynamic feature encoding with anatomically guided supervision. Leveraging a hybrid architecture based on 3D convolutional layers and ConvLSTM modules, the model captures both spatial structures and temporal motion patterns across full cardiac cycles. Shape-aware loss functions - including signed distance function (SDF) loss and boundary-based constraints - are incorporated to ensure anatomical fidelity, reducing segmentation artifacts and improving topological correctness. Evaluated across benchmark datasets such as ACDC, M&Ms, and UK Biobank, the model consistently achieved Dice scores above 92.1% and reduced Hausdorff distances to 5.2mm. Compared to conventional 2D/3D CNNs, this framework showed a 3.7-4.5% increase in segmentation accuracy and an 18-25% reduction in boundary leakage, particularly in complex regions such as the apex and basal slices. The suggested technique accomodates strong generalization over pathological cases, ensuring temporal coherence and clinical applicability. Its encoder-decoder framework is still flexible to different sequence lengths and resolutions to facilitate scalable deployment in real-time diagnostic and surgical planning applications
Structural Changes in the Temporomandibular Joint After Botulinum Toxin Injection Into the Masseter Muscle in Experimentally Induced Osteoarthritis in Rats
No full textBackground: Botulinum neurotoxin (BoNT) injections into the masticatory muscles have been used as a treatment to improve symptoms related to temporomandibular joint (TMJ) disorders. However, its safety and long-term effects on TMJ structures remain inconclusive and are still under discussion. Objective: The purpose of this study is to evaluate whether the effects of BoNT injection into the masseter affect the mandibular condyle in a rat model of TMJ osteoarthritis (TMJ-OA). Methods: Sixteen male Wistar albino rats were used. The 32 TMJ joints were divided into four groups: (1) TMJ-OA with BoNT (OA + BTX), (2) TMJ-OA without BoNT (OA), (3) BoNT without TMJ-OA (BTX) and (4) control. TMJ-OA was induced by CFA injections. One week later, BoNT was administered to the masseter in the OA + BTX and BTX groups. Micro-CT imaging was performed 8 weeks later to assess the TMJ condyle. Results: The analysis revealed significant differences in bone mineral density and microarchitectural changes between the BTX/control and the OA/OA-BTX groups, except for trabecular separation (p < 0.05). The OA and OA + BTX groups exhibited lower bone volume fraction and bone mineral density compared to the BTX and control groups. No significant differences were observed between the BTX and the groups without BoNT, suggesting that BoNT did not result in bone loss in healthy TMJs or in TMJ-OA cases. Conclusions: BoNT does not have a significant effect on healthy or existing degenerative conditions in the TMJ. Long-term experimental studies and clinical trials are needed to validate the safety of BoNT in managing TMJ-OA
Neural network based frequency adaptive digital predistortion of RF power amplifiers
Full text linkArticle number : 62
CODEN : AICPELinearization of power amplifiers (PAs) is a big challenge in high-dimensional radio frequency (RF) designs, and to tackle this drawback we propose an adaptive strategy with the combination of neural networks (NNs) and band-pass filters for input signals with different frequencies that results in reduced computational costs. The proposed linearization approach is based on utilization of NN for modeling the PA and band-pass filters for contributing to frequency adaptability without feedback loop. Thus, even if the frequency of the input signal changes, the system may still produce linear output. The proposed model consists of sub-digital predistortion (DPD) blocks where each sub-DPD block generates DPD coefficients only for the specified frequency range. Thanks to sub-DPD blocks without feedback, the computational load of the model is reduced and computation time is saved. To validate the proposed model, the PA is first characterized using the neural network. Then, the frequency of the input signal is determined via band-pass filtering. Based on this frequency information, the corresponding NN-based sub-DPD block is activated to linearize the PA’s nonlinear behavior. For the presented PA that is operating from 1.7 GHz to 2 GHz, four different input signal frequencies values as 1.7 GHz, 1.9 GHz, 2.1 GHz, 2.4 GHz respectively are carried out. The achieved results prove that the proposed model provides improved PA modeling and nonlinear compensation compared to the other methods. The 1-dB compression point of the PA is measured as–6.88 dBm without DPD, 4.49 dBm with look-up table-based DPD, and 7 dBm with NN-based DPD