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13 pages, 776 KiB  
Systematic Review
Factors Associated with Non-Compliance with Healthcare Accreditation in Saudi Arabia: A Systematic Review and Meta-Analysis
by Khalid Saad Alkhurayji, Abdulmunim Alsuhaimi, Hesham Alangari, Saja A. Alrayes and Arwa Alumran
Healthcare 2025, 13(6), 580; https://doi.org/10.3390/healthcare13060580 (registering DOI) - 7 Mar 2025
Abstract
Background/Objectives: Compliance with healthcare standards is an absolute must for every healthcare organization seeking accreditation. Several factors were found to affect compliance, and in Saudi Arabia, certain standards were observed for non-compliance. Therefore, this systematic review and meta-analysis seeks to identify the [...] Read more.
Background/Objectives: Compliance with healthcare standards is an absolute must for every healthcare organization seeking accreditation. Several factors were found to affect compliance, and in Saudi Arabia, certain standards were observed for non-compliance. Therefore, this systematic review and meta-analysis seeks to identify the factors associated with non-compliance with healthcare accreditation in Saudi Arabia. Methods: This study adheres to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. The population, intervention, comparison, and outcome (PICO) model was used to refine the research question. The Peer Review of Electronic Search Strategies (Press) guidelines were used to improve the search strategy. The databases used for the search were PubMed, Web of Science, Scopus, and Google Scholar. The dates searched were from 1 January 2000 to 1 November 2024. We used a data extraction form for study characteristics and outcome data, which was piloted on five studies in this review. The risk of bias was assessed by using the Joanna Briggs Institute (JBI) tool and the Mixed Methods Appraisal Tool (MMAT). The analysis was carried out using the Fisher r-to-z transformed correlation coefficient as the outcome measure. A random-effects model was fitted to the data. Results: A total of ten studies were included for qualitative synthesis and five for quantitative synthesis. Several factors were observed for non-compliance, including insufficient training organization hurdles, a lack of implementation strategies, and the attitudes of healthcare providers. The estimated average correlation coefficient based on the random-effects model was 0.2568 (95% CI: −0.1190 to 0.6326). Conclusions: The dimension of quality in healthcare through pooled correlations from various studies highlighted a weak association among these dimensions. Full article
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<p>PRISMA flowchart.</p>
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<p>Forest plot of non-compliance factors [<a href="#B29-healthcare-13-00580" class="html-bibr">29</a>,<a href="#B30-healthcare-13-00580" class="html-bibr">30</a>,<a href="#B35-healthcare-13-00580" class="html-bibr">35</a>,<a href="#B36-healthcare-13-00580" class="html-bibr">36</a>,<a href="#B37-healthcare-13-00580" class="html-bibr">37</a>].</p>
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28 pages, 1473 KiB  
Article
Maximum Trimmed Likelihood Estimation for Discrete Multivariate Vasicek Processes
by Thomas M. Fullerton, Michael Pokojovy, Andrews T. Anum and Ebenezer Nkum
Economies 2025, 13(3), 68; https://doi.org/10.3390/economies13030068 (registering DOI) - 6 Mar 2025
Abstract
The multivariate Vasicek model is commonly used to capture mean-reverting dynamics typical for short rates, asset price stochastic log-volatilities, etc. Reparametrizing the discretized problem as a VAR(1) model, the parameters are oftentimes estimated using the multivariate least squares (MLS) method, which can be [...] Read more.
The multivariate Vasicek model is commonly used to capture mean-reverting dynamics typical for short rates, asset price stochastic log-volatilities, etc. Reparametrizing the discretized problem as a VAR(1) model, the parameters are oftentimes estimated using the multivariate least squares (MLS) method, which can be susceptible to outliers. To account for potential model violations, a maximum trimmed likelihood estimation (MTLE) approach is utilized to derive a system of nonlinear estimating equations, and an iterative procedure is developed to solve the latter. In addition to robustness, our new technique allows for reliable recovery of the long-term mean, unlike existing methodologies. A set of simulation studies across multiple dimensions, sample sizes and robustness configurations are performed. MTLE outcomes are compared to those of multivariate least trimmed squares (MLTS), MLE and MLS. Empirical results suggest that MTLE not only maintains good relative efficiency for uncontaminated data but significantly improves overall estimation quality in the presence of data irregularities. Additionally, real data examples containing daily log-volatilities of six common assets (commodities and currencies) and US/Euro short rates are also analyzed. The results indicate that MTLE provides an attractive instrument for interest rate forecasting, stochastic volatility modeling, risk management and other applications requiring statistical robustness in complex economic and financial environments. Full article
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Figure 1
<p>Simulated <math display="inline"><semantics> <mover accent="true"> <mo form="prefix">err</mo> <mo>^</mo> </mover> </semantics></math> values for <math display="inline"><semantics> <mrow> <mi>ε</mi> <mo>=</mo> <mn>0.20</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>ncp</mi> <mo>=</mo> <mn>50</mn> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <mi>bdp</mi> <mo>=</mo> <mn>0.25</mn> </mrow> </semantics></math>.</p>
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<p>Simulated <math display="inline"><semantics> <mover accent="true"> <mo form="prefix">err</mo> <mo>^</mo> </mover> </semantics></math> values for <math display="inline"><semantics> <mrow> <mi>ε</mi> <mo>=</mo> <mn>0.30</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>ncp</mi> <mo>=</mo> <mn>25</mn> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <mi>bdp</mi> <mo>=</mo> <mn>0.35</mn> </mrow> </semantics></math>.</p>
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<p>Simulated <math display="inline"><semantics> <mover accent="true"> <mo form="prefix">err</mo> <mo>^</mo> </mover> </semantics></math> values for <math display="inline"><semantics> <mrow> <mi>ε</mi> <mo>=</mo> <mn>0.20</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>ncp</mi> <mo>=</mo> <mn>25</mn> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <mi>bdp</mi> <mo>=</mo> <mn>0.25</mn> </mrow> </semantics></math>.</p>
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<p>Simulated <math display="inline"><semantics> <mover accent="true"> <mo form="prefix">err</mo> <mo>^</mo> </mover> </semantics></math> values for <math display="inline"><semantics> <mrow> <mi>ε</mi> <mo>=</mo> <mn>0.10</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>ncp</mi> <mo>=</mo> <mn>25</mn> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <mi>bdp</mi> <mo>=</mo> <mn>0.35</mn> </mrow> </semantics></math>.</p>
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<p>Historic US/EU 3-month rates (1 January 2023–31 12 December 2023) as well as forecasted mean and 90% projection bands (1 January 2024–31 March 2024).</p>
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<p>The contour plots of the probability density function of the forecasted short rate <math display="inline"><semantics> <msub> <mi mathvariant="bold-italic">R</mi> <mi>t</mi> </msub> </semantics></math> distribution on 31 March 2024.</p>
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<p>Sphered empirical residuals for MTLE (<math display="inline"><semantics> <mrow> <mi>bdp</mi> <mo>=</mo> <mn>0.2</mn> </mrow> </semantics></math>), MLTS (<math display="inline"><semantics> <mrow> <mi>bdp</mi> <mo>=</mo> <mn>0.2</mn> </mrow> </semantics></math>), MLE and MLS estimators with respective 95% prediction circles.</p>
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<p>Empirical backtesting root-MSE and MAPE using MTLE, MLTS, MLE and MLS estimators.</p>
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<p>Daily logged volatilities: July 2017–June 2020.</p>
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<p>Estimates of <math display="inline"><semantics> <msup> <mi mathvariant="bold-italic">R</mi> <mo>∗</mo> </msup> </semantics></math> for daily log-volatilities with <math display="inline"><semantics> <mrow> <mi>w</mi> <mo>=</mo> <mn>50</mn> </mrow> </semantics></math>.</p>
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26 pages, 11289 KiB  
Article
Angle Estimation Based on Wave Path Difference Rate of Change Ambiguity Function
by Jianye Xu, Maozhong Fu and Zhenmiao Deng
Remote Sens. 2025, 17(5), 943; https://doi.org/10.3390/rs17050943 (registering DOI) - 6 Mar 2025
Abstract
Modern radar systems commonly utilize monopulse angle estimation techniques for target angle estimation, with the phase comparison method being one of the most widely adopted approaches. While the phase comparison method achieves high estimation precision, it is highly susceptible to noise and exhibits [...] Read more.
Modern radar systems commonly utilize monopulse angle estimation techniques for target angle estimation, with the phase comparison method being one of the most widely adopted approaches. While the phase comparison method achieves high estimation precision, it is highly susceptible to noise and exhibits a suboptimal performance under low Signal-to-Noise Ratio (SNR) conditions, leading to a high SNR threshold. Moreover, conventional monopulse angle estimation methods provide limited target information, as a single measurement cannot reveal the target’s motion direction. To address these shortcomings, a novel approach based on the phase comparison method is proposed in this study, with the variation in the wave path difference modeled as a first-order motion model. By accumulating the conjugate-multiplied signals over multiple time steps, the Wave Path Difference Rate of Change Ambiguity Function (WPD-ROC AF) is constructed. A fast algorithm employing the 2D Chirp-Z Transform (2D-CZT) is proposed, enabling multi-pulse angle estimation through the identification of frequency and phase values corresponding to spectral peaks. Simulation results validate that the proposed method outperforms traditional monopulse angle estimation techniques under low-SNR conditions and effectively suppresses static clutter interference. Furthermore, the sign of the WPD-ROC AF is shown to be correlated with the target’s motion direction, providing practical utility for determining the direction of movement in remote sensing scenarios. Full article
(This article belongs to the Section Remote Sensing Image Processing)
34 pages, 586 KiB  
Article
A Fractional Adams Method for Caputo Fractional Differential Equations with Modified Graded Meshes
by Yuhui Yang and Yubin Yan
Mathematics 2025, 13(5), 891; https://doi.org/10.3390/math13050891 (registering DOI) - 6 Mar 2025
Abstract
In this paper, we introduce an Adams-type predictor–corrector method based on a modified graded mesh for solving Caputo fractional differential equations. This method not only effectively handles the weak singularity near the initial point but also reduces errors associated with large intervals in [...] Read more.
In this paper, we introduce an Adams-type predictor–corrector method based on a modified graded mesh for solving Caputo fractional differential equations. This method not only effectively handles the weak singularity near the initial point but also reduces errors associated with large intervals in traditional graded meshes. We prove the error estimates in detail for both 0<α<1 and 1<α<2 cases, where α is the order of the Caputo fractional derivative. Numerical experiments confirm the convergence of the proposed method and compare its performance with the traditional graded mesh approach. Full article
(This article belongs to the Section E: Applied Mathematics)
13 pages, 774 KiB  
Article
Association of Hormone Replacement Therapy with Inflammatory Bowel Disease Risk in Women with Menopausal Disorders: A Population-Based Retrospective Cohort Study
by Yuan-Tsung Tseng, I-I Chen and Chun-Hsiang Wang
Healthcare 2025, 13(5), 578; https://doi.org/10.3390/healthcare13050578 - 6 Mar 2025
Abstract
Abstract: Background: The long-term effects of hormone replacement therapy (HRT) on inflammatory bowel disease (IBD) remain unclear, necessitating further investigations of the association between HRT and the development of ulcerative colitis and Crohn’s disease in postmenopausal women. Methods: This retrospective cohort study [...] Read more.
Abstract: Background: The long-term effects of hormone replacement therapy (HRT) on inflammatory bowel disease (IBD) remain unclear, necessitating further investigations of the association between HRT and the development of ulcerative colitis and Crohn’s disease in postmenopausal women. Methods: This retrospective cohort study utilized Taiwan’s National Health Insurance claims (2001–2018) to identify postmenopausal women aged ≥50 years with HRT use. A one-year washout period was applied before the index date to ensure new HRT users. To address the immortal time bias, follow-up for HRT users began at HRT initiation. The non-HRT group was selected by 1:1 propensity score matching. Cox proportional hazards models with adjustments for comorbidities and medications were used to estimate hazard ratios. Results: A total of 10,126 postmenopausal women (5063 per group) were included. During a mean follow-up of 11.1 years, the incidence rates of ulcerative colitis were 0.14 and 0.11 per 1000 person-years in the HRT and non-HRT groups, respectively. The adjusted hazard ratios were 1.33 (95% CI, 0.46–3.83; p = 0.600) for ulcerative colitis and 0.72 (95% CI, 0.45–1.16; p = 0.177) for Crohn’s disease. Conclusions: This longitudinal study suggests that HRT use is not significantly associated with the risk of IBD among postmenopausal women. These findings indicate that IBD risk may not need to be a primary concern when considering HRT in this population. Full article
18 pages, 24582 KiB  
Article
A Simple Model for Estimating the Kinematics of Tape-like Unstable Bases from Angular Measurements near Anchor Points
by Heinz Hegi and Ralf Kredel
Sensors 2025, 25(5), 1632; https://doi.org/10.3390/s25051632 - 6 Mar 2025
Abstract
Sensorimotor training on an unstable base of support is considered to lead to improvements in balance and coordination tasks. Here, we intend to lay the groundwork for generating cost-effective real-time kinematic feedback for coordination training on devices with an unstable base of support, [...] Read more.
Sensorimotor training on an unstable base of support is considered to lead to improvements in balance and coordination tasks. Here, we intend to lay the groundwork for generating cost-effective real-time kinematic feedback for coordination training on devices with an unstable base of support, such as Sensopros or slacklines, by establishing a model for estimating relevant tape kinematic data from angle measurements alone. To assess the accuracy of the model in a real-world setting, we record a convenience sample of three people performing ten exercises on the Sensopro Luna and compare the model predictions to motion capture data of the tape. The measured accuracy is reported for each target measure separately, namely the roll angle and XYZ-position of the tape segment directly below the foot. After the initial assessment of the model in its general form, we also propose how to adjust the model parameters based on preliminary measurements to adapt it to a specific setting and further improve its accuracy. The results show that the proposed method is viable for recording tape kinematic data in real-world settings, and may therefore serve as performance indicator directly or form the basis for estimating posture and other measures related to human motor control in a more intricate training feedback system. Full article
(This article belongs to the Special Issue Sensors for Human Posture and Movement)
19 pages, 2730 KiB  
Article
Sub-Pixel Displacement Measurement with Swin Transformer: A Three-Level Classification Approach
by Yongxing Lin, Xiaoyan Xu and Zhixin Tie
Appl. Sci. 2025, 15(5), 2868; https://doi.org/10.3390/app15052868 - 6 Mar 2025
Abstract
In order to avoid the dependence of traditional sub-pixel displacement methods on interpolation method calculation, image gradient calculation, initial value estimation and iterative calculation, a Swin Transformer-based sub-pixel displacement measurement method (ST-SDM) is proposed, and a square dataset expansion method is also proposed [...] Read more.
In order to avoid the dependence of traditional sub-pixel displacement methods on interpolation method calculation, image gradient calculation, initial value estimation and iterative calculation, a Swin Transformer-based sub-pixel displacement measurement method (ST-SDM) is proposed, and a square dataset expansion method is also proposed to rapidly expand the training dataset. The ST-SDM computes sub-pixel displacement values of different scales through three-level classification tasks, and solves the problem of positive and negative displacement with the rotation relative tag value method. The accuracy of the ST-SDM is verified by simulation experiments, and its robustness is verified by real rigid body experiments. The experimental results show that the ST-SDM model has higher accuracy and higher efficiency than the comparison algorithm. Full article
17 pages, 591 KiB  
Article
Enhancing Uplink Communication in Wireless Powered Communication Networks Through Rate-Splitting Multiple Access and Joint Resource Optimization
by Iqra Hameed, Mario R. Camana, Mohammad Abrar Shakil Sejan and Hyoung Kyu Song
Mathematics 2025, 13(5), 888; https://doi.org/10.3390/math13050888 - 6 Mar 2025
Abstract
Wireless powered communication networks (WPCNs) provide a sustainable solution for energy-constrained IoT devices by enabling wireless energy transfer (WET) in the downlink and wireless information transmission (WIT) in the uplink. However, their performance is often limited by interference in uplink communication and inefficient [...] Read more.
Wireless powered communication networks (WPCNs) provide a sustainable solution for energy-constrained IoT devices by enabling wireless energy transfer (WET) in the downlink and wireless information transmission (WIT) in the uplink. However, their performance is often limited by interference in uplink communication and inefficient resource allocation. To address these challenges, we propose an RSMA-aided WPCN framework, which optimizes rate-splitting factors, power allocation, and time division to enhance spectral efficiency and user fairness. To solve this non-convex joint optimization problem, we employ the simultaneous perturbation stochastic approximation (SPSA) algorithm, a gradient-free method that efficiently estimates optimal parameters with minimal function evaluations. Compared to conventional optimization techniques, SPSA provides a scalable and computationally efficient approach for real-time resource allocation in RSMA-aided WPCNs. Our simulation results demonstrate that the proposed RSMA-aided framework improves sum throughput by 12.5% and enhances fairness by 15–20% compared to conventional multiple-access schemes. These findings establish RSMA as a key enabler for next-generation WPCNs, offering a scalable, interference-resilient, and energy-efficient solution for future wireless networks. Full article
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<p>The RSMA-aided wireless powered communication network (WPCN) framework. The hybrid access point (H-AP) first transmits energy to users <math display="inline"><semantics> <msub> <mi>U</mi> <mn>1</mn> </msub> </semantics></math> and <math display="inline"><semantics> <msub> <mi>U</mi> <mn>2</mn> </msub> </semantics></math> via wireless energy transfer (WET), followed by wireless information transmission (WIT) in the uplink. Each user employs RSMA, where messages are split into two parts, optimally allocated for power and transmitted to the H-AP.</p>
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<p>Convergence of proposed SPSA-based algorithm for different transmit power levels.</p>
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<p>Sum throughput versus transmit power at H-AP for different schemes.</p>
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<p>Throughput of <math display="inline"><semantics> <msub> <mi>U</mi> <mn>2</mn> </msub> </semantics></math> versus transmit power at H-AP for different schemes.</p>
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<p>Sum throughput versus distance between <math display="inline"><semantics> <msub> <mi>U</mi> <mn>1</mn> </msub> </semantics></math> and <math display="inline"><semantics> <msub> <mi>U</mi> <mn>2</mn> </msub> </semantics></math> for different schemes.</p>
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<p>Throughput of <math display="inline"><semantics> <msub> <mi>U</mi> <mn>2</mn> </msub> </semantics></math> versus distance between <math display="inline"><semantics> <msub> <mi>U</mi> <mn>1</mn> </msub> </semantics></math> and <math display="inline"><semantics> <msub> <mi>U</mi> <mn>2</mn> </msub> </semantics></math> for different schemes.</p>
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<p>Sum throughput versus transmit power at H-AP.</p>
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17 pages, 1257 KiB  
Article
Enhanced Emotion Recognition Through Dynamic Restrained Adaptive Loss and Extended Multimodal Bottleneck Transformer
by Dang-Khanh Nguyen, Eunchae Lim, Soo-Hyung Kim, Hyung-Jeong Yang and Seungwon Kim
Appl. Sci. 2025, 15(5), 2862; https://doi.org/10.3390/app15052862 - 6 Mar 2025
Abstract
Emotion recognition in video aims to estimate human emotions using acoustic, visual, and linguistic information. This problem is considered multimodal and requires learning different modalities, such as visual, verbal, and vocal cues. Although previous studies have focused on developing sophisticated deep learning models, [...] Read more.
Emotion recognition in video aims to estimate human emotions using acoustic, visual, and linguistic information. This problem is considered multimodal and requires learning different modalities, such as visual, verbal, and vocal cues. Although previous studies have focused on developing sophisticated deep learning models, this work proposes a different approach using dynamic restrained adaptive loss inspired by multitask learning to understand multimodal inputs jointly. This training strategy allows predictions from one modality to enhance the accuracy of predictions from other modalities, mirroring the concept of multitask learning, where the results of one task can improve the performance of related tasks. Furthermore, this work introduces the extended multimodal bottleneck transformer, an efficient and effective mid-fusion method designed for problems involving more than two modalities to enhance the performance of emotion recognition systems. The proposed method significantly improves results compared to other end-to-end multimodal fusion techniques on three multimodal benchmarks—Interactive Emotional Dyadic Motion Capture (IEMOCAP), Carnegie Mellon University Multimodal Opinion Sentiment and Emotion Intensity (CMU-MOSEI), and the Chinese Multimodal Sentiment Analysis dataset with independent unimodal annotations (CH-SIMS). Full article
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Figure 1
<p>Proposed multimodal learning framework (<b>a</b>) developed from traditional multimodal learning (<b>b</b>) and inspired by multitask learning (<b>c</b>).</p>
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<p>Block diagram of the proposed framework.</p>
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<p>Illustration of proposed XMBT.</p>
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<p>CMU-MOSEI and IEMOCAP test results for XMBT by training strategy.</p>
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<p>Evaluation metrics of IEMOCAP.</p>
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<p>CMU-MOSEI test results of XMBT and open-ended MBT variants.</p>
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<p>CMU-MOSEI test results of XMBT by temperature and number of bottleneck layers.</p>
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<p>T-SNE visualization of modal-specific representations of IEMOCAP samples using (<b>upper</b>) conventional loss function and (<b>lower</b>) DRA loss function.</p>
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39 pages, 810 KiB  
Article
Limit Theorems for Kernel Regression Estimator for Quasi-Associated Functional Censored Time Series Within Single Index Structure
by Said Attaoui, Oum Elkheir Benouda, Salim Bouzebda and Ali Laksaci
Mathematics 2025, 13(5), 886; https://doi.org/10.3390/math13050886 - 6 Mar 2025
Abstract
In this paper, we develop kernel-based estimators for regression functions under a functional single-index model, applied to censored time series data. By capitalizing on the single-index structure, we reduce the dimensionality of the covariate-response relationship, thereby preserving the ability to capture intricate dependencies [...] Read more.
In this paper, we develop kernel-based estimators for regression functions under a functional single-index model, applied to censored time series data. By capitalizing on the single-index structure, we reduce the dimensionality of the covariate-response relationship, thereby preserving the ability to capture intricate dependencies while maintaining a relatively parsimonious form. Specifically, our framework utilizes nonparametric kernel estimation within a quasi-association setting to characterize the underlying relationships. Under mild regularity conditions, we demonstrate that these estimators attain both strong uniform consistency and asymptotic normality. Through extensive simulation experiments, we confirm their robust finite-sample performance. Moreover, an empirical examination using intraday Nikkei stock index returns illustrates that the proposed method significantly outperforms traditional nonparametric regression approaches. Full article
(This article belongs to the Special Issue Probability, Stochastic Processes and Machine Learning)
24 pages, 8456 KiB  
Article
Design and Implementation of a Low-Pressure Briquetting Machine for the Use of Pinus spp. Wood Residues: An Approach to Appropriate Rural Technology
by Mario Morales-Máximo, Víctor Manuel Ruíz-García, José Guadalupe Rutiaga-Quiñones and Luis Bernado López-Sosa
Clean Technol. 2025, 7(1), 22; https://doi.org/10.3390/cleantechnol7010022 - 6 Mar 2025
Abstract
This research analyzes the technical feasibility and implementation of an appropriate technology for the production of briquettes from Pinus spp. waste (sawdust and shavings) in a rural community in Michoacán, Mexico. The results indicate that local small-scale briquette production in the Pichátaro community [...] Read more.
This research analyzes the technical feasibility and implementation of an appropriate technology for the production of briquettes from Pinus spp. waste (sawdust and shavings) in a rural community in Michoacán, Mexico. The results indicate that local small-scale briquette production in the Pichátaro community has the potential to boost a local economy based on the manufacturing and marketing of densified solid biofuels. The design of the manual briquetting machine was developed through a participatory approach with community users. Structural simplicity and locally accessible maintenance were prioritized, the aspects that were addressed little in previous studies. The machine allows for the production of briquettes using a low-cost mixture composed of sawdust and Pinus spp. shavings, corn starch, and water. Based on local conditions and production needs, parameters such as reduced processing times and simplified manufacturing methods were identified as essential to establishing an efficient regional production and supply chain. Furthermore, the valorization of solid waste through the production of alternative biofuels contributes to the diversification of the energy matrix in rural residential sectors and small industries in communities in Mexico. The estimated cost of the machine is USD 75.44, and most of its components are easily replaceable, which favors its sustainability and prolonged use. This study demonstrates that the implementation of a low-pressure briquette system based on appropriate rural technologies represents a viable strategy for the use of wood waste and the promotion of sustainable energy solutions in rural communities. Full article
28 pages, 5467 KiB  
Article
AFSA-FastICA-CEEMD Rolling Bearing Fault Diagnosis Method Based on Acoustic Signals
by Jin Yan, Fubing Zhou, Xu Zhu and Dapeng Zhang
Mathematics 2025, 13(5), 884; https://doi.org/10.3390/math13050884 - 6 Mar 2025
Abstract
As one of the key components in rotating machinery, rolling bearings have a crucial impact on the safety and efficiency of production. Acoustic signal is a commonly used method in the field of mechanical fault diagnosis, but an overlapping phenomenon occurs very easily, [...] Read more.
As one of the key components in rotating machinery, rolling bearings have a crucial impact on the safety and efficiency of production. Acoustic signal is a commonly used method in the field of mechanical fault diagnosis, but an overlapping phenomenon occurs very easily, which affects the diagnostic accuracy. Therefore, effective blind source separation and noise reduction of the acoustic signals generated between different devices is the key to bearing fault diagnosis using acoustic signals. To this end, this paper proposes a blind source separation method based on an AFSA-FastICA (Artificial Fish Swarm Algorithm, AFSA). Firstly, the foraging and clustering characteristics of the AFSA algorithm are utilized to perform global optimization on the aliasing matrix W, and then inverse transformation is performed on the global optimal solution W, to obtain a preliminary estimate of the source signal. Secondly, the estimated source signal is subjected to CEEMD noise reduction, and after obtaining the modal components of each order, the number of interrelationships is used as a constraint on the modal components, and signal reconstruction is performed. Finally, the signal is subjected to frequency domain feature extraction and bearing fault diagnosis. The experimental results indicate that,  the new method successfully captures three fault characteristic frequencies (1fi, 2fi, and 3fi), with their energy distribution concentrated in the range of 78.9 Hz to 228.7 Hz, indicative of inner race faults. Similarly, when comparingthe diffent results with each other, the denoised source signal spectrum successfully captures the frequencies 1fo, 2fo, and 3fo and their sideband components, which are characteristic of outer race faults. The sideband components generated in the above spectra are preliminarily judged to be caused by impacts between the fault location and nearby components, resulting in modulated frequency bands where the modulation frequency corresponds to the rotational frequency and its harmonics. Experiments show that the method can effectively diagnose the bearing faults. Full article
(This article belongs to the Special Issue Numerical Analysis in Computational Mathematics)
16 pages, 14943 KiB  
Article
Immunohistochemical Evaluation of the Tumor Immune Microenvironment in Pancreatic Ductal Adenocarcinoma
by Gelu Mihai Breaza, Raluca Maria Closca, Alexandru Cristian Cindrea, Florin Emil Hut, Octavian Cretu, Laurentiu Vasile Sima, Marina Rakitovan and Flavia Zara
Diagnostics 2025, 15(5), 646; https://doi.org/10.3390/diagnostics15050646 - 6 Mar 2025
Abstract
Background: Pancreatic ductal adenocarcinoma is an aggressive neoplasm with a complex carcinogenesis process that must be understood through the interactions between tumor cells and tumor microenvironment cells. Methods: This study was retrospective with a chronological extension period of 16 years and [...] Read more.
Background: Pancreatic ductal adenocarcinoma is an aggressive neoplasm with a complex carcinogenesis process that must be understood through the interactions between tumor cells and tumor microenvironment cells. Methods: This study was retrospective with a chronological extension period of 16 years and included 56 cases of pancreatic ductal adenocarcinoma. This study identified, quantified, and correlated the cells of the tumor immune microenvironment in pancreatic ductal adenocarcinoma with major prognostic factors as well as overall survival, using an extensive panel of immunohistochemical markers. Results: Three tumor immunotypes were identified: subtype A (hot immunotype), subtype B (intermediate immunotype), and subtype C (cold immunotype). Patients with immunotype C exhibit considerably higher rates of both pancreatic fistulas and acute pancreatitis. Immunotypes B and C significantly increased the risk of this complication by factors of 3.68 (p = 0.002) and 3.94 (p = 0.001), respectively. The estimated probabilities of fistula formation for each immunotype are as follows: 2.5% for immunotype A, 25% for immunotype B, and 28% for immunotype C. There was a statistically significant difference in median survival times according to tumor immunotype (p < 0.001). Specifically, patients with immunotype C tumors had a median survival time of only 120.5 days, compared to 553.5 days for those with immunotype A and 331.5 for immunotype B tumors. Conclusions: The identification of the immunotype of pancreatic ductal adenocarcinoma can be a predictive factor for the occurrence of complications such as pancreatic fistula as well as for overall survival. Full article
(This article belongs to the Special Issue Diagnosis of Pancreatic Diseases)
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<p>Flowchart of the case selection.</p>
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<p>Morphological aspect and immunohistochemical profile of the pancreatic ductal adenocarcinoma immunotype A, ob.10× (ob.40× in the corner): (<b>a</b>) hematoxylin-eosin staining; (<b>b</b>) LCA; (<b>c</b>) CD20; (<b>d</b>) CD3; (<b>e</b>) CD4; (<b>f</b>) CD8; (<b>g</b>) CD5; (<b>h</b>) CD117; (<b>i</b>) CD68; (<b>j</b>) CD1a; FI: front of invasion.</p>
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<p>Morphological aspect and immunohistochemical profile of the pancreatic ductal adenocarcinoma immunotype B, ob.10× (ob.40× in the corner): (<b>a</b>) hematoxylin-eosin staining; (<b>b</b>) LCA; (<b>c</b>) CD20; (<b>d</b>) CD3; (<b>e</b>) CD4; (<b>f</b>) CD8; (<b>g</b>) CD5; (<b>h</b>) CD117.</p>
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<p>Morphological aspect and immunohistochemical profile of the pancreatic ductal adenocarcinoma immunotype C, ob.10× (ob.40× in the corner): (<b>a</b>) hematoxylin-eosin staining; (<b>b</b>) LCA; (<b>c</b>) CD20; (<b>d</b>) CD3; (<b>e</b>) CD4; (<b>f</b>) CD8; (<b>g</b>) CD5; (<b>h</b>) CD117.</p>
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<p>Histochemical aspects of tumor immunotypes in Masson’s trichrome staining, ob.5×: (<b>a</b>) immunotype A; (<b>b</b>) immunotype B; (<b>c</b>) immunotype C.</p>
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<p>Box plots for survival time by cancer subtype.</p>
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<p>Survival curves by cancer subtype.</p>
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13 pages, 8983 KiB  
Systematic Review
Efficacy and Safety of Combination Therapy with PARP Inhibitors and Anti-Angiogenic Agents in Ovarian Cancer: A Systematic Review and Meta-Analysis
by István Baradács, Brigitta Teutsch, Ádám Vincze, Péter Hegyi, Bence Szabó, Péter Nyirády, Nándor Ács, Zsolt Melczer, Ferenc Bánhidy and Balázs Lintner
J. Clin. Med. 2025, 14(5), 1776; https://doi.org/10.3390/jcm14051776 - 6 Mar 2025
Abstract
Introduction: Ovarian cancer is a significant contributor to gynecological cancer-related mortality, necessitating innovative treatment strategies. This systematic review and meta-analysis aimed to assess the efficacy and safety of combining PARP inhibitors with anti-angiogenic agents (AAAs) in the treatment of ovarian cancer. Methods: This [...] Read more.
Introduction: Ovarian cancer is a significant contributor to gynecological cancer-related mortality, necessitating innovative treatment strategies. This systematic review and meta-analysis aimed to assess the efficacy and safety of combining PARP inhibitors with anti-angiogenic agents (AAAs) in the treatment of ovarian cancer. Methods: This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and was registered on PROSPERO (CRD42022319461). A systematic search of three electronic databases, including MEDLINE (via PubMed), EMBASE, and Cochrane Library was conducted to identify relevant randomized controlled trials (RCT) that evaluated the efficacy and safety of the combination therapy. Subgroup analyses were based on BRCA mutation status. Meta-analysis was conducted to estimate pooled hazard ratios (HR) and risk ratios (RR) for progression-free survival (PFS) and adverse events, respectively. The combination therapy was compared to PARP inhibitors alone and to chemotherapy. Heterogeneity was assessed using Higgins and Thompson’s I2 statistic where applicable. Results: Seven RCTs involving 2397 patients were included. Combination therapy did not show a statistically significant improvement in PFS compared to PARP inhibitor monotherapy in the general population (HR 0.63, CI 0.37–1.06), or in BRCA-mutated (HR 0.70, CI 0.30–1.63) and BRCA wild-type subgroups (HR 0.39, CI 0.14–1.07). When compared to chemotherapy, combination therapy produced no significant PFS benefit in recurrent ovarian cancer (HR 0.83, CI 0.42–1.63) in the total population. Safety analysis revealed that hypertension and diarrhea were significantly more frequent in combination therapy compared with PARP inhibitors alone (RR 6.80, CI 2.87–16.06 and RR 10.04, CI 2.25–44.75) or chemotherapy alone (RR 13.80, CI 3.43–55.57 and RR 6.57, CI 2.84–15.24). Conclusions: The combination of PARP inhibitors and AAAs did not demonstrate a statistically significant benefit in PFS compared to PARP inhibitors or chemotherapy alone in recurrent ovarian cancer. While the combination therapy was generally well tolerated, hypertension and diarrhea occurred significantly. These findings suggest that combination therapy may not provide a clear survival advantage in the recurrent setting. Further high-quality, biomarker-driven clinical trials are needed to refine patient selection, optimize toxicity management, and determine the potential role of combination therapy in ovarian cancer treatment. Full article
(This article belongs to the Section Obstetrics & Gynecology)
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<p>PRISMA 2020 flowchart representing the study selection process.</p>
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<p>Forest plot representing the efficacy of combination therapy vs. PARP inhibitor alone in recurrent ovarian cancer. The asterisk (*) indicates that this is the second publication by the same author in the same year.</p>
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<p>Forest plot representing the efficacy of combination therapy vs. chemotherapy alone in recurrent ovarian cancer.</p>
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<p>Forest plot representing risk ratios of grade 3 ≤ adverse events for combination therapy vs. PARP inhibitors alone in recurrent ovarian cancer.</p>
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<p>Forest plot representing risk ratios of grade 3 ≤ adverse events for combination therapy vs. chemotherapy alone in recurrent ovarian cancer.</p>
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17 pages, 9938 KiB  
Article
Study on Spatially Nonstationary Impact on Catering Distribution: A Multiscale Geographically Weighted Regression Analysis Using POI Data
by Lu Tan and Xiaojun Bu
ISPRS Int. J. Geo-Inf. 2025, 14(3), 119; https://doi.org/10.3390/ijgi14030119 - 6 Mar 2025
Abstract
Factors related to catering distribution are typically characterized by local changes, but few studies have quantitatively investigated the inherent spatial nonstationarity correlations. In this study, a multiscale geographically weighted regression (MGWR) model was adopted to locally examine the impact of various factors on [...] Read more.
Factors related to catering distribution are typically characterized by local changes, but few studies have quantitatively investigated the inherent spatial nonstationarity correlations. In this study, a multiscale geographically weighted regression (MGWR) model was adopted to locally examine the impact of various factors on catering distribution, which were obtained through a novel method incorporating GeoDetector analysis and exploratory factor analysis (EFA) using point of interest (POI) data. GeoDetector analysis was used to identify the effective variables that truly contribute to catering distribution, and EFA was adopted to extract interpretable latent factors based on the underlying structure of the effective variables and thus eliminate multicollinearity. In our case study in Nanjing, China, four primary factors, namely commuting activities, shopping activities, tourism activities, and gathering activities, were retained from eight categories of POIs with respect to catering distribution. The results suggested that GeoDetector working in tandem with EFA could improve the representativeness of factors and infer POI configuration patterns. The MGWR model explained the most variations (adj. R2: 0.903) with the lowest AICc compared to the OLS regression model and the geographically weighted regression (GWR) model. Mapping MGWR parameter estimates revealed the spatial variability of relationships between various factors and catering distribution. The findings provide useful insights for guiding catering development and optimizing urban functional spaces. Full article
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<p>Location of the study area.</p>
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<p>The normalized spatial distribution of (<b>a</b>) catering point density and the candidate variables: (<b>b</b>) transportation, (<b>c</b>) residential, (<b>d</b>) office, (<b>e</b>) commerce, (<b>f</b>) education, (<b>g</b>) healthcare, (<b>h</b>) tourism, and (<b>i</b>) venues.</p>
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<p>The normalized spatial distribution of (<b>a</b>) catering point density and the candidate variables: (<b>b</b>) transportation, (<b>c</b>) residential, (<b>d</b>) office, (<b>e</b>) commerce, (<b>f</b>) education, (<b>g</b>) healthcare, (<b>h</b>) tourism, and (<b>i</b>) venues.</p>
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<p>Research framework.</p>
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<p>Interaction detection results.</p>
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<p>Distribution of local residuals from the OLS model (<b>a</b>), the GWR model (<b>b</b>), and the MGWR model (<b>c</b>).</p>
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<p>MGWR local parameter estimates for (<b>a</b>) Factor 1, (<b>b</b>) Factor 2 (<b>c</b>), Factor 3, and (<b>d</b>) Factor 4.</p>
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<p>MGWR local parameter estimates for (<b>a</b>) Factor 1, (<b>b</b>) Factor 2 (<b>c</b>), Factor 3, and (<b>d</b>) Factor 4.</p>
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