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17 pages, 3511 KiB  
Article
Fixed-Time Trajectory Tracking Control of Fully Actuated Unmanned Surface Vessels with Error Constraints
by Bowen Sui, Jianqiang Zhang, Zhong Liu and Junbao Wei
J. Mar. Sci. Eng. 2024, 12(4), 584; https://doi.org/10.3390/jmse12040584 (registering DOI) - 29 Mar 2024
Abstract
This paper proposes a fixed-time prescribed performance control technique to address the challenge of precise trajectory tracking control for unmanned surface vessels (USVs) in the presence of external time-varying disturbances and input saturation. To begin with, a fixed-time disturbance observer is created to [...] Read more.
This paper proposes a fixed-time prescribed performance control technique to address the challenge of precise trajectory tracking control for unmanned surface vessels (USVs) in the presence of external time-varying disturbances and input saturation. To begin with, a fixed-time disturbance observer is created to handle the time-varying external interference. The observer can accurately estimate and compensate for the disturbance in a fixed time, which effectively improves the robustness of the system. Furthermore, to guarantee both the transient and steady-state response of the system, we employed a specific control technology that ensures the trajectory tracking error remains within a preset bounded range. Then, combined with the fixed-time disturbance observer, the command filter, the prescribed performance control technology, and the fixed-time stability theory, a fixed-time trajectory tracking control law is designed to make the trajectory tracking error of the system converge in a fixed time. Finally, an experiment was designed to validate the suggested control scheme. The results show that under the same conditions, compared with the nonlinear controller and the finite-time controller, the absolute error tracking index of this paper is the lowest, which means that the presented control scheme has higher accuracy. Full article
(This article belongs to the Section Ocean Engineering)
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17 pages, 4364 KiB  
Article
Broadband Beam-Scanning Phased Array Based on Microwave Photonics
by Yuchen Luan, Tian Yang, Jian Ren, Ruoming Li and Zhuo Zhang
Electronics 2024, 13(7), 1278; https://doi.org/10.3390/electronics13071278 (registering DOI) - 29 Mar 2024
Abstract
A one-dimensional active broadband phased array based on microwave photonics that works in the Ku band is proposed to achieve a large instantaneous bandwidth. The phased array uses a feeding network based on microwave photonics to provide the true time delay and a [...] Read more.
A one-dimensional active broadband phased array based on microwave photonics that works in the Ku band is proposed to achieve a large instantaneous bandwidth. The phased array uses a feeding network based on microwave photonics to provide the true time delay and a wide operating bandwidth. The array is mainly composed of a broadband horn antenna, an RF transmitting/receiving module, an optical network module, and a temperature control module. The form of a horn was selected for the antenna unit, and it was fed through a waveguide to obtain a wide operating bandwidth. An optical fiber delay line that could realize the true time delay at different frequencies was adopted for the time-delay module of the optical network. To obtain a large time delay and small quantization error, a hybrid time-delay diagram utilizing electrical and optical time delays was used in the design. In addition, a temperature control module was added to the antenna system to enhance the stability of the photonic time-delay module. For verification, a prototype of the presented antenna system was designed, fabricated, and measured. The experimental results showed that the optical phased array antenna was able to scan ±20° from 12 GHz to 17 GHz, and the beam pointing did not appear to be offset over the wide operating bandwidth. Full article
(This article belongs to the Special Issue Advanced Technologies in Antennas and Their Applications)
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18 pages, 19106 KiB  
Article
Thermodynamic Assessment of Molten Bix-Sn1−x (x = 0.1 to 0.9) Alloys and Microstructural Characterization of Some Bi-Sn Solder Alloys
by Florentina Niculescu, Ion Pencea, Gheorghe Iacob, Mihai Ghi??, Mariana-Mirela St?nescu, Mircea-Ionu? Petrescu, Emanuel-Lauren?iu Niculescu, Mihai Bu?u, Constantin-Domenic St?ncel, Nicolae ?erban, Roxana-Marina ?olea and Andrei-Alexandru Ilie
Materials 2024, 17(7), 1579; https://doi.org/10.3390/ma17071579 (registering DOI) - 29 Mar 2024
Abstract
Properties such as lower melting temperature, good tensile strength, good reliability, and well creep resistance, together with low production cost, make the system Bi-Sn an ideal candidate for fine soldering in applications such as reballing or reflow. The first objective of the work [...] Read more.
Properties such as lower melting temperature, good tensile strength, good reliability, and well creep resistance, together with low production cost, make the system Bi-Sn an ideal candidate for fine soldering in applications such as reballing or reflow. The first objective of the work was to determine the thermodynamic quantities of Bi and Sn using the electromotive force measurement method in an electrolytic cell (Gibbs’ enthalpies of the mixture, integral molar entropies, and the integral molar excess entropies were determined) at temperatures of 600 K and 903 K. The second objective addressed is the comprehensive characterization of three alloy compositions that were selected and elaborated, namely Bi25Sn75, Bi50Sn50, and Bi75Sn25, and morphological and structural investigations were carried out on them. Optical microscopy and SEM-EDS characterization revealed significant changes in the structure of the elaborated alloys, with all phases being uniformly distributed in the Bi50Sn50 and Bi75Sn25 alloys. These observations were confirmed by XRD and EDP-XRFS analyses. Diffractometric analysis reveals the prevalence of metallic Bi and traces of Sn, the formation of the Sn0.3Bi0.7, Sn0.95Bi0.05 compounds, and SnO and SnO2 phases. Full article
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13 pages, 458 KiB  
Article
The Effects of Slaughter Age and Sex on Carcass Traits, Meat Quality, and Leg Bone Characteristics of Farmed Common Pheasants (Phasianus colchicus L.)
by Dariusz Kokoszyński, Joanna ?ochowska-Kujawska, Marek Kotowicz, Hubert Pi?tek, Karol W?odarczyk, Henrieta Arpá?ová, Barbara Biesiada-Drzazga, Marcin Wegner, Mohamed Saleh and Maciej Imański
Animals 2024, 14(7), 1050; https://doi.org/10.3390/ani14071050 (registering DOI) - 29 Mar 2024
Abstract
The aim of this study was to determine the effects of slaughter age and sex on the carcass characteristics, meat quality parameters, and leg bone dimensions of common pheasants. The study material consisted of 40 common pheasants, including 10 males and 10 females [...] Read more.
The aim of this study was to determine the effects of slaughter age and sex on the carcass characteristics, meat quality parameters, and leg bone dimensions of common pheasants. The study material consisted of 40 common pheasants, including 10 males and 10 females at 12 weeks of age and 10 males and 10 females at 15 weeks of age. The birds were kept on a farm in a semi-intensive system. The slaughter age had significant effects on the eviscerated carcass weight; the percentage of skin with subcutaneous fat; the wings percentage; electrical conductivity (EC24); the work required to cut the samples (cutting work); redness (a*); the intramuscular fat content in the breast meat; and the protein, intramuscular fat, water, and collagen contents in the leg meat. The sex of the pheasants had significant effects on the eviscerated carcass weight; the contents of leg muscles, skin with subcutaneous fat, and wings in the carcasses; and the electrical conductivity, thermal loss, lightness (L*), and redness (a*) of the breast muscles. It also significantly affected the protein and water contents of the pectoral and leg muscles, the intramuscular fat contents of the leg muscles, the texture traits of the pectoralis major muscle, and all femur and tibia bone dimensions. The results indicate a greater influence of sex compared to slaughter age on the pheasant traits studied. We confirmed the occurrence of a clearly marked sexual dimorphism in birds of this species. Both factors (slaughter age and gender) have significant effects on the nutritional and technological value of pheasant meat. The few studies on meat texture and the dimensions of pheasant leg bones indicate a need for continued research in this area in the future. Full article
(This article belongs to the Section Animal Products)
16 pages, 599 KiB  
Article
Enhancing Patient Care in Radiotherapy: Proof-of-Concept of a Monitoring Tool
by Guillaume Beldjoudi, Rémi Eugène, Vincent Grégoire and Ronan Tanguy
Technologies 2024, 12(4), 46; https://doi.org/10.3390/technologies12040046 (registering DOI) - 29 Mar 2024
Abstract
Introduction: A monitoring tool, named Oncology Data Management (ODM), was developed in radiotherapy to generate structured information based on data contained in an Oncology Information System (OIS). This study presents the proof-of-concept of the ODM tool and highlights its applications to enhance patient [...] Read more.
Introduction: A monitoring tool, named Oncology Data Management (ODM), was developed in radiotherapy to generate structured information based on data contained in an Oncology Information System (OIS). This study presents the proof-of-concept of the ODM tool and highlights its applications to enhance patient care in radiotherapy. Material & Methods: ODM is a sophisticated SQL query which extracts specific features from the Mosaiq OIS (Elekta, UK) database into an independent structured database. Data from 2016 to 2022 was extracted to enable monitoring of treatment units and evaluation of the quality of patient care. Results: A total of 25,259 treatments were extracted. Treatment machine monitoring revealed a daily 11-treatement difference between two units. ODM showed that the unit with fewer daily treatments performed more complex treatments on diverse locations. In 2019, the implementation of ODM led to the definition of quality indicators and in organizational changes that improved the quality of care. As consequences, for palliative treatments, there was an improvement in the proportion of treatments prepared within 7 calendar days between the scanner and the first treatment session (29.1% before 2020, 40.4% in 2020 and 46.4% after 2020). The study of fractionation in breast treatments exhibited decreased prescription variability after 2019, with distinct patient age categories. Bi-fractionation once a week for larynx prescriptions of 35 x 2.0Gy achieved an overall treatment duration of 47.0 ± 3.0 calendar days in 2022. Conclusions: ODM enables data extraction from the OIS and provides quantitative tools for improving organization of a department and the quality of patient care in radiotherapy. Full article
(This article belongs to the Topic Smart Healthcare: Technologies and Applications)
21 pages, 5647 KiB  
Article
Physical Modeling of a Water Hydraulic Proportional Cartridge Valve for a Digital Twin in a Hydraulic Press Machine
by Oscar Bautista Gonzalez and Daniel R?nnow
Processes 2024, 12(4), 693; https://doi.org/10.3390/pr12040693 (registering DOI) - 29 Mar 2024
Abstract
Digital twins are an emerging technology that can be harnessed for the digitalization of the industry. Steel industry systems contain a large number of electro-hydraulic components as proportional valves. An input–output model for a water proportional cartridge valve was derived from physical modeling [...] Read more.
Digital twins are an emerging technology that can be harnessed for the digitalization of the industry. Steel industry systems contain a large number of electro-hydraulic components as proportional valves. An input–output model for a water proportional cartridge valve was derived from physical modeling based on fluid mechanics, dynamics, and electrical principles. The valve is a two-stage valve with two two/two-way water proportional valves as the pilot stage and a marginally stable poppet-type cartridge valve as the main valve. To our knowledge, this is the first time that an input–output model was derived for a two-stage proportional cartridge valve with a marginally stable main valve. The orifice equation, which is based on Bernoulli principles, was approximated by a polynomial, which made the parameter estimation easier and modeling possible without measuring the pressure of the varying control volume, in contrast with previous studies of similar types of valves situated in the pilot stage part of the valve. This work complements previous studies of similar types of valves in two ways: (1) data were collected when the valve was operating in a closed loop and (2) data were collected when the valve was part of a press mill machine in a steel manufacturing plant. Model parameters were identified from data from these operating conditions. The parameters of the input–output model were estimated by convex optimization with physical constraints to overcome the problems caused by poor system excitation. For comparison, a simple linear model was derived and the least squares method was used for the parameter estimation. A thorough estimation of the parameters’ relative errors is presented. The model contains five parameters related to the design parameters of the valve. The modeled position output was in good agreement with experimental data for the training and test data. The model can be used for the real-time monitoring of the valve’s status by the model parameters. One of the model parameters varied linearly with the production cycles. Thus, the aging of the valve can be monitored. Full article
(This article belongs to the Section Automation Control Systems)
16 pages, 824 KiB  
Article
Calculation of DC Stark Resonances for the Ammonia Molecule
by Patrik Pirkola and Marko Horbatsch
Molecules 2024, 29(7), 1543; https://doi.org/10.3390/molecules29071543 (registering DOI) - 29 Mar 2024
Abstract
A model potential previously developed for the ammonia molecule is treated in a single-center partial-wave approximation in analogy with a self-consistent field method developed by Moccia. The latter was used in a number of collision studies. The model potential is used to calculate [...] Read more.
A model potential previously developed for the ammonia molecule is treated in a single-center partial-wave approximation in analogy with a self-consistent field method developed by Moccia. The latter was used in a number of collision studies. The model potential is used to calculate DC Stark resonance parameters, i.e., resonance positions and shifts using the exterior complex scaling method for the radial coordinate. Three molecular valence orbitals are investigated for fields along the three Cartesian coordinates, i.e., along the molecular axis and in two perpendicular directions. The work extends previous work on the planar-geometry water molecule for which non-monotonic shifts were observed. We find such non-monotonic shifts for fields along the molecular axis. For perpendicular fields, we report the splitting of the 1e orbitals into a fast- and a slow-ionizing orbital. Full article
(This article belongs to the Section Computational and Theoretical Chemistry)
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18 pages, 4398 KiB  
Article
Sex-Dependent Metabolic Effects in Diet-Induced Obese Rats Following Intermittent Fasting Compared with Continuous Food Restriction
by Laia Bosch de Basea, Marina Bogu?à, Alicia Sánchez, Montserrat Esteve, Mar Grasa and Maria del Mar Romero
Nutrients 2024, 16(7), 1009; https://doi.org/10.3390/nu16071009 (registering DOI) - 29 Mar 2024
Abstract
Recently, intermittent fasting has gained relevance as a strategy to lose weight and improve health as an alternative to continuous caloric restriction. However, the metabolic impact and the sex-related differences are not fully understood. The study aimed to compare the response to a [...] Read more.
Recently, intermittent fasting has gained relevance as a strategy to lose weight and improve health as an alternative to continuous caloric restriction. However, the metabolic impact and the sex-related differences are not fully understood. The study aimed to compare the response to a continuous or intermittent caloric restriction in male and female rats following a previous induction of obesity through a cafeteria diet by assessing changes in body weight, energy intake, metabolic parameters, and gene expression in liver hepatic and adipose tissue. The continuous restriction reduced the energy available by 30% and the intermittent restriction consisted of a 75% energy reduction on two non-consecutive days per week. The interventions reduced body weight and body fat in both sexes, but the loss of WAT in females was more marked in both models of caloric restriction, continuous and intermittent. Both caloric restrictions improved insulin sensitivity, but more markedly in females, which showed a more pronounced decrease in HOMA-IR score and an upregulation of hepatic IRS2 and Sirt1 gene expression that was not observed in males. These findings suggest the fact that females are more sensitive than males to reduced caloric content in the diet. Full article
(This article belongs to the Special Issue Nutritional Regulation of Insulin Resistance and Lipid Metabolism)
31 pages, 3592 KiB  
Article
Cross-Modal Supervised Human Body Pose Recognition Techniques for Through-Wall Radar
by Dongpo Xu, Yunqing Liu, Qian Wang, Liang Wang and Qiuping Shen
Sensors 2024, 24(7), 2207; https://doi.org/10.3390/s24072207 (registering DOI) - 29 Mar 2024
Abstract
Through-wall radar human body pose recognition technology has broad applications in both military and civilian sectors. Identifying the current pose of targets behind walls and predicting subsequent pose changes are significant challenges. Conventional methods typically utilize radar information along with machine learning algorithms [...] Read more.
Through-wall radar human body pose recognition technology has broad applications in both military and civilian sectors. Identifying the current pose of targets behind walls and predicting subsequent pose changes are significant challenges. Conventional methods typically utilize radar information along with machine learning algorithms such as SVM and random forests to aid in recognition. However, these approaches have limitations, particularly in complex scenarios. In response to this challenge, this paper proposes a cross-modal supervised through-wall radar human body pose recognition method. By integrating information from both cameras and radar, a cross-modal dataset was constructed, and a corresponding deep learning network architecture was designed. During training, the network effectively learned the pose features of targets obscured by walls, enabling accurate pose recognition (e.g., standing, crouching) in scenarios with unknown wall obstructions. The experimental results demonstrated the superiority of the proposed method over traditional approaches, offering an effective and innovative solution for practical through-wall radar applications. The contribution of this study lies in the integration of deep learning with cross-modal supervision, providing new perspectives for enhancing the robustness and accuracy of target pose recognition. Full article
(This article belongs to the Section Radar Sensors)
15 pages, 837 KiB  
Case Report
Evolutionary Echoes: A Four-Day Fasting and Low-Caloric Intake Study on Autonomic Modulation and Physiological Adaptations in Humans
by Pedro Belinchón-deMiguel, Eduardo Navarro-Jiménez, Carmen Cecilia Laborde-Cárdenas and Vicente Javier Clemente-Suárez
Life 2024, 14(4), 456; https://doi.org/10.3390/life14040456 (registering DOI) - 29 Mar 2024
Abstract
This study evaluates the psychophysiological response to a simulated hunter–gatherer endurance task with restricted caloric intake over four days. It assesses changes in body composition, autonomic modulation, and physical and cognitive performance. Participants underwent daily 8 h fasted walks followed by a 150 [...] Read more.
This study evaluates the psychophysiological response to a simulated hunter–gatherer endurance task with restricted caloric intake over four days. It assesses changes in body composition, autonomic modulation, and physical and cognitive performance. Participants underwent daily 8 h fasted walks followed by a 150 kcal meal to replicate hunter–gatherer activity and dietary patterns. Measurements of metabolic, respiratory, and subjective well-being, along with heart rate variability (HRV) monitoring, were conducted pre- and post-activity to evaluate the impact of endurance activity under caloric restriction. We found weight loss, decreased body and visceral fat, and reduced skeletal muscle mass and water percentage. High sympathetic activation and stable urinary markers, except for increased proteinuria, indicated stress responses and muscular degradation. Elevated perceived exertion post-exercise with good adaptation to prolonged effort underlines the body’s adaptability to ancestral lifestyle conditions, highlighting the connection among endurance, nutrition, and psychophysiological health. Full article
(This article belongs to the Special Issue Advances and Applications of Sport Physiology)
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18 pages, 522 KiB  
Article
Effects of Two Online Mindfulness-Based Interventions for Early Adolescents for Attentional, Emotional, and Behavioral Self-Regulation
by Bárbara Porter, Cristian Oyanadel, Ignacio Betancourt, Frank C. Worrell and Wenceslao Pe?ate
Pediatr. Rep. 2024, 16(2), 254-271; https://doi.org/10.3390/pediatric16020022 (registering DOI) - 29 Mar 2024
Abstract
(1) Background: Mindfulness-based interventions (MBIs) have shown interesting preliminary effects on self-regulation processes in early adolescence. However, programs have typically combined different types of interventions with no understanding of the specific effect of each intervention type on attentional, emotional, and behavioral regulation. The [...] Read more.
(1) Background: Mindfulness-based interventions (MBIs) have shown interesting preliminary effects on self-regulation processes in early adolescence. However, programs have typically combined different types of interventions with no understanding of the specific effect of each intervention type on attentional, emotional, and behavioral regulation. The objective of this research was to evaluate the effect of two MBIs—one focused on classic attentional practices and another focused on the recognition and expression of emotions—on attentional, emotional, and behavioral self-regulation in early adolescents. (2) Method: An experimental paradigm was used. A sample of 74 children aged between 8 and 12 years old were randomly assigned to three experimental conditions: (1) an MBI with a focus on attentional practices, (2) an MBI with a focus on recognition and expression of emotions, and (3) a control group. The interventions lasted 8 weeks, with a weekly, 1 h online synchronous session plus home practices. Children were evaluated before starting the intervention and at the end of the 8-week period. The assessed outcomes were (1) mindfulness; (2) emotional regulation; (3) attentional regulation, and (4) behavioral regulation. (3) Results: Children who participated in both intervention programs increased their mindfulness and emotional and behavioral regulation scores. Only children who participated in the MBI with a focus on attention showed significant changes in their ability to self-regulate attention. (4) Conclusions: The use of online MBIs, with attention to external and internal stimuli practices, can be a good strategy to strengthen self-regulation skills for attention, emotions, and behavior in early adolescence. Full article
28 pages, 2702 KiB  
Article
EPOPTIS: A Monitoring-as-a-Service Platform for Internet-of-Things Applications
by Petros Zervoudakis, Nikolaos Karamolegkos, Eleftheria Plevridi, Pavlos Charalampidis and Alexandros Fragkiadakis
Sensors 2024, 24(7), 2208; https://doi.org/10.3390/s24072208 (registering DOI) - 29 Mar 2024
Abstract
The technology landscape has been dynamically reshaped by the rapid growth of the Internet of Things, introducing an era where everyday objects, equipped with smart sensors and connectivity, seamlessly interact to create intelligent ecosystems. IoT devices are highly heterogeneous in terms of software [...] Read more.
The technology landscape has been dynamically reshaped by the rapid growth of the Internet of Things, introducing an era where everyday objects, equipped with smart sensors and connectivity, seamlessly interact to create intelligent ecosystems. IoT devices are highly heterogeneous in terms of software and hardware, and many of them are severely constrained. This heterogeneity and potentially constrained nature creates new challenges in terms of security, privacy, and data management. This work proposes a Monitoring-as-a-Service platform for both monitoring and management purposes, offering a comprehensive solution for collecting, storing, and processing monitoring data from heterogeneous IoT networks for the support of diverse IoT-based applications. To ensure a flexible and scalable solution, we leverage the FIWARE open-source framework, also incorporating blockchain and smart contract technologies to establish a robust integrity verification mechanism for aggregated monitoring and management data. Additionally, we apply automated workflows to filter and label the collected data systematically. Moreover, we provide thorough evaluation results in terms of CPU and RAM utilization and average service latency. Full article
(This article belongs to the Special Issue Advances in Intelligent Sensors and IoT Solutions)
11 pages, 413 KiB  
Systematic Review
Robotic Vascular Resection in Pancreatic Ductal Adenocarcinoma: A Systematic Review
by Victoria Zecchin Ferrara, Alessandro Martinino, Francesco Toti, Davide Schilirò, Federico Pinto, Francesco Giovinazzo and on behalf of the SMAGEICS Group
J. Clin. Med. 2024, 13(7), 2000; https://doi.org/10.3390/jcm13072000 (registering DOI) - 29 Mar 2024
Abstract
(1) Background: This study comprehensively compared robotic pancreatic surgery with vascular resection (RPS-VR) to other surgical procedures in the treatment of pancreatic ductal adenocarcinoma (PDAC). (2) Methods: A systematic review of relevant literature was conducted to assess a range of crucial surgical and [...] Read more.
(1) Background: This study comprehensively compared robotic pancreatic surgery with vascular resection (RPS-VR) to other surgical procedures in the treatment of pancreatic ductal adenocarcinoma (PDAC). (2) Methods: A systematic review of relevant literature was conducted to assess a range of crucial surgical and oncological outcomes. (3) Results: Findings indicate that robotic surgery with vascular resections (VRs) significantly prolongs the duration of surgery compared to other surgical procedures, and they notably demonstrate an equal hospital stay. While some studies reported a lower conversion rate and a higher rate of blood loss and blood transfusion in the RPS-VR group, others found no significant disparity. Furthermore, RPS-VR consistently correlated with comparable recurrence rates, free margins R0, postoperative mortality, and complication rates. Concerning the last one, certain reviews reported a higher rate of major complications. Overall survival and disease-free survival remained comparable between the RPS-VR and other surgical techniques in treating PDAC. (4) Conclusions: The analysis emphasizes how RPS-VR is a resembling approach in terms of surgical outcomes and aligns with existing literature findings in this field. Full article
(This article belongs to the Special Issue Advances in Hepatobiliary Surgery)
17 pages, 1689 KiB  
Article
Benefits of Respite Services on the Psycho-Emotional State of Families of Children Admitted to Hospice Palliative Care Unit: Preliminary Study on Parents’ Perceptions
by Mihaela Hizanu (Dumitrache), Estera Boeriu, Sonia Tanasescu, Ada Balan, Licinia Andrada Oprisoni, Maria Valentina Popa, Cristian Gutu, Dan Dumitru Vulcanescu, Iulia Cristina Bagiu, Radu Vasile Bagiu, Tiberiu Liviu Dragomir, Casiana Boru, Cecilia Roberta Avram and Leti?ia Doina Duceac
Healthcare 2024, 12(7), 748; https://doi.org/10.3390/healthcare12070748 (registering DOI) - 29 Mar 2024
Abstract
Background: In children’s palliative care, the term “respite” refers to a temporary break offered to primary caregivers of a child with a life-limiting illness. The aim of this study was to assess the perceptions of parents who have benefited from respite care services [...] Read more.
Background: In children’s palliative care, the term “respite” refers to a temporary break offered to primary caregivers of a child with a life-limiting illness. The aim of this study was to assess the perceptions of parents who have benefited from respite care services in the Lumina Association, Bacău hospice unit and the benefits it can bring in improving their psycho-emotional state. Methods: The study consisted of quantitative research involving 34 parents/caregivers who responded to a questionnaire with 26 questions, and qualitative research which involved the organization of a focus group with 12 parents who benefited from respite services. Results: The use of respite services was associated with a significant reduction of psycho-emotional distress on the part of primary caregivers; 91% of respondents said that this type of service reduces the level of psycho-emotional stress. Conclusions: All participants in the study confirmed that the most important benefit of respite is the time gained to care for family and health. The development of respite services could reduce the risk of emotional exhaustion and mental health problems. Full article
16 pages, 724 KiB  
Article
Optimization of Signal Detection Using Deep CNN in Ultra-Massive MIMO
by Chittapon Keawin, Apinya Innok and Peerapong Uthansakul
Telecom 2024, 5(2), 280-295; https://doi.org/10.3390/telecom5020014 (registering DOI) - 29 Mar 2024
Abstract
This paper addresses the evolving landscape of communication technology, emphasizing the pivotal role of 5G and the emerging 6G networks in accommodating the increasing demand for high-speed and accurate data transmission. We delve into the advancements in 5G technology, particularly the implementation of [...] Read more.
This paper addresses the evolving landscape of communication technology, emphasizing the pivotal role of 5G and the emerging 6G networks in accommodating the increasing demand for high-speed and accurate data transmission. We delve into the advancements in 5G technology, particularly the implementation of millimeter wave (mmWave) frequencies ranging from 30 to 300 GHz. These advancements are instrumental in enhancing applications requiring massive data transmission and reception, facilitated by massive MIMO (multiple input multiple output) systems. Looking towards the future, this paper forecasts the necessity for faster data transmission technologies, shifting the focus toward the development of 6G networks. These future networks are projected to employ ultra-massive MIMO systems in the terahertz band, operating within 0.1–10 THz frequency ranges. A significant part of our research is dedicated to exploring advanced signal detection techniques, helping to mitigate the impact of interference and improve accuracy in data transmission and enabling more efficient communication, even in environments with high levels of noise, and including zero forcing (ZF) and minimum mean square error (MMSE) methods, which form the cornerstone of our proposed approach. Additionally, signal detection contributes to the development of new communication technologies such as 5G and 6G, which require a high data transmission efficiency and rapid response speeds. The core contribution of this study lies in the application of deep learning to signal detection in ultra-massive MIMO systems, a critical component of 6G technology. We compare this approach with existing ELMx-based machine learning methods, focusing on algorithmic efficiency and computational performance. Our comparative analysis included the regularized extreme learning machine (RELM) and the outlier robust extreme learning machine (ORELM), juxtaposed with ZF and MMSE methods. Simulation results indicated the superiority of our convolutional neural network for signal detection (CNN-SD) over the traditional ELMx-based, ZF, and MMSE methods, particularly in terms of channel capacity and bit error rate. Furthermore, we demonstrate the computational efficiency and reduced complexity of the CNN-SD method, underscoring its suitability for future expansive MIMO systems. Full article
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17 pages, 4844 KiB  
Article
Analysis of Magnetohydrodynamic Free Convection in Micropolar Fluids over a Permeable Shrinking Sheet with Slip Boundary Conditions
by Param R. Tangsali, Nagaraj N. Katagi, Ashwini Bhat and Manjunath Shettar
Symmetry 2024, 16(4), 400; https://doi.org/10.3390/sym16040400 (registering DOI) - 29 Mar 2024
Abstract
The convective micropolar fluid flow over a permeable shrinking sheet in the presence of a heat source and thermal radiation with the magnetic field directed towards the sheet has been studied in this paper. The mathematical formulation considers the partial slip condition at [...] Read more.
The convective micropolar fluid flow over a permeable shrinking sheet in the presence of a heat source and thermal radiation with the magnetic field directed towards the sheet has been studied in this paper. The mathematical formulation considers the partial slip condition at the sheet, allowing a realistic representation of the fluid flow near the boundary. The governing equations for the flow, heat, and mass transfer are formulated using the conservation laws of mass, momentum, angular momentum, energy, and concentration. The resulting nonlinear partial differential equations are transformed into a system of ordinary differential equations using suitable similarity transformations. The numerical solutions are obtained using robust computational techniques to examine the influence of various parameters on the velocity, temperature, and concentration profiles. The impact of slip effects, micropolar fluid characteristics, and permeability parameters on the flow features and heat transfer rates are thoroughly analyzed. The findings of this investigation offer valuable insights into the behavior of micropolar fluids in free convection flows over permeable shrinking sheets with slip, providing a foundation for potential applications in various industrial and engineering processes. Key findings include the observation that the velocity profile overshoots for assisting flow with decreasing viscous force and rising magnetic effects as opposed to opposing flow. The thermal boundary layer thickness decreases due to buoyant force but shows increasing behavior with heat source parameters. The present result agrees with the earlier findings for specific parameter values in particular cases. Full article
(This article belongs to the Section Mathematics)
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19 pages, 10507 KiB  
Article
Innovative Cellular Insulation Barrier on the Basis of Voronoi Tessellation—Influence of Internal Structure Optimization on Thermal Performance
by Beata Anwajler, Sara Zielińska and Anna Witek-Krowiak
Materials 2024, 17(7), 1578; https://doi.org/10.3390/ma17071578 (registering DOI) - 29 Mar 2024
Abstract
The optimization of structure and thermal properties in 3D-printed insulation materials remains an underexplored area in the literature. This study aims to address this gap by investigating the impact of 3D printing on the thermal properties of manufactured cellular composites. The materials studied [...] Read more.
The optimization of structure and thermal properties in 3D-printed insulation materials remains an underexplored area in the literature. This study aims to address this gap by investigating the impact of 3D printing on the thermal properties of manufactured cellular composites. The materials studied were closed-cell foams with a complex cell structure based on the Voronoi cell model, manufactured using incremental technology (3D printing). The influence of the cellular structure of the composite, the type of material used, and the number of layers in the composite structure on its thermal properties, i.e., thermal conductivity coefficient, thermal resistance, and coefficient of heat transfer, was analyzed. Samples of different types of thermosetting resins, characterized by different values of emissivity coefficient, were analyzed. It was shown that both the type of material, the number of layers of the composite, and the number of pores in its structure significantly affect its thermal insulating properties. Thermal conductivity and permeability depended on the number of layers and decreased up to 30% as the number of layers increased from one to four, while thermal resistance increased to 35%. The results indicate that material structure is key in regulating thermal conduction. Controlling the number of cells in a given volume of composite (and thus the size of the air cells) and the number of layers in the composite can be an effective tool in designing materials with high insulation performance. Among the prototype composites produced, the best thermal performance was that of the metalized four-layer cellular composites (λ = 0.035 ± 0.002 W/m·K, Rc = 1.15 ± 0.02 K·m2/W, U = 0.76 ± 0.01 W/m2·K). Full article
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17 pages, 397 KiB  
Article
Study of the Influence of Doping Efficiency of CeO2 Ceramics with a Stabilizing Additive Y2O3 on Changes in the Strength and Thermophysical Parameters of Ceramics under High-Temperature Irradiation with Heavy Ions
by Artem L. Kozlovskiy, Sholpan G. Giniyatova, Dmitriy I. Shlimas, Daryn B. Borgekov, Ruslan M. Rspayev and Maxim V. Zdorovets
Crystals 2024, 14(4), 320; https://doi.org/10.3390/cryst14040320 (registering DOI) - 29 Mar 2024
Abstract
The article outlines findings from a comparative analysis of the effectiveness of doping CeO2 ceramics with a stabilizing additive Y2O3 on alterations in the strength and thermophysical parameters of ceramics under high-temperature irradiation with heavy ions comparable in energy [...] Read more.
The article outlines findings from a comparative analysis of the effectiveness of doping CeO2 ceramics with a stabilizing additive Y2O3 on alterations in the strength and thermophysical parameters of ceramics under high-temperature irradiation with heavy ions comparable in energy to fission fragments of nuclear fuel, which allows, during high-temperature irradiation, to simulate radiation damage that is as similar as possible to the fission processes of nuclear fuel. During the studies, it was found that the addition of a stabilizing additive Y2O3 to the composition of CeO2 ceramics in the case of high-temperature irradiation causes an increase in stability to swelling and softening because of a decrease in the thermal expansion of the crystal lattice by 3–8 times in comparison with unstabilized CeO2 ceramics. It has been determined that the addition of a stabilizing additive Y2O3 leads not only to a rise in the resistance of the crystal structure to deformation distortions and swelling, but also to a decrease in the effect of thermal expansion of the crystal structure, which has an adverse effect on the structural ordering of CeO2 ceramics exposed to irradiation at high temperatures. Full article
(This article belongs to the Section Polycrystalline Ceramics)
14 pages, 2471 KiB  
Article
Detection of Hardening in Mangosteens Using Near-Infrared Hyperspectral Imaging
by Saranya Workhwa, Thitirat Khanthong, Napatsorn Manmak, Anthony Keith Thompson and Sontisuk Teerachaichayut
Horticulturae 2024, 10(4), 345; https://doi.org/10.3390/horticulturae10040345 (registering DOI) - 29 Mar 2024
Abstract
Mangosteens can develop a postharvest physiological disorder, called “hardening”, which affects their marketability and is not detectable using visual inspection. The hardening disorder of mangosteens was determined by firmness value using the texture analyzer. Near-infrared hyperspectral imaging (NIR-HSI) in the region of 935–1720 [...] Read more.
Mangosteens can develop a postharvest physiological disorder, called “hardening”, which affects their marketability and is not detectable using visual inspection. The hardening disorder of mangosteens was determined by firmness value using the texture analyzer. Near-infrared hyperspectral imaging (NIR-HSI) in the region of 935–1720 nm was tested as a possible rapid and non-destructive method to detect this disorder. The spectra from a region of interest of mangosteens were acquired and used for analysis. Calibration models for firmness of a similarly sized group and a mixed-size group were established using partial least squares regression (PLSR) and support vector machine regression (SVMR). Chemometric algorithms were investigated in order to determine the optimal conditions for establishing the models for firmness. The optimum model was obtained when the fruit were graded into similarly sized groups. Using partial least squares regression (PLSR), the correlation coefficient of prediction (Rp) was 0.87 and the root mean square error of prediction (RMSEP) was 6.25 N. The predictive images for firmness of the fruit were created by interpreting predicted firmness visualized as colors in every pixel. From the data, it was concluded that NIR-HSI can potentially be used to visualize hardening of individual mangosteens based on their predictive images. Full article
(This article belongs to the Section Postharvest Biology, Quality, Safety, and Technology)
18 pages, 5343 KiB  
Article
Gentiopicrin-Loaded Chitosan Nanoparticles as a Topical Agent for the Treatment of Psoriasis
by Guohua Cheng, Xiaojie Zhang, Huiling Zhang, Zhixuan Feng, Jiaxiu Cai, Jingjing Li, Libo Du and Ke Liu
Nanomaterials 2024, 14(7), 610; https://doi.org/10.3390/nano14070610 (registering DOI) - 29 Mar 2024
Abstract
Psoriasis, a chronic inflammatory skin disease induced by various factors, including genetic factors, immune factors, environmental factors, and psychological factors, is characterized by thickening of the epidermis, excessive proliferation of keratinocytes, abnormal differentiation, and an excessive inflammatory response. Traditional treatments for psoriasis still [...] Read more.
Psoriasis, a chronic inflammatory skin disease induced by various factors, including genetic factors, immune factors, environmental factors, and psychological factors, is characterized by thickening of the epidermis, excessive proliferation of keratinocytes, abnormal differentiation, and an excessive inflammatory response. Traditional treatments for psoriasis still face challenges because of limited curative effects, notable side effects, and a tendency for recurrence. In contrast, topical therapy provides a favorable option for psoriasis treatment because of its noninvasive and self-administered method. In this study, gentiopicrin (Gen) is encapsulated in the liposomes to form a nanodrug, and then chitosan is covered on the nanodrug to assemble the nanodrug delivery system (CS@Gen), which is used as a topical agent for treating psoriasis. Then M5 (a mixture of five pro-inflammatory cytokines, i.e., IL-17A, IL-22, IL-1α, oncostatin M, and TNF-α)-induced HacaT cells and imiquimod-induced psoriasis mouse models are established, whose results show that CS@Gen induces apoptosis and inhibits the proliferation and cell migration of psoriasis keratinocytes. Additionally, the application of CS@Gen cream can significantly reduce epidermal thickness, diminish skin scaling, and improve other related mechanisms in mice affected by psoriasis. Meanwhile, the prepared CS@Gen can significantly reduce the expression levels of IL-17a, Cxcl2, S100a, Mki67, and other related inflammatory factors, resulting in indirectly inhibiting the inflammation of keratinocytes. In summary, the present study provides an ideal loading for an anti-inflammatory and immunomodulatory drug delivery system for the treatment of psoriasis. Full article
(This article belongs to the Section Biology and Medicines)
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10 pages, 4593 KiB  
Article
New Diterpenes and Diterpene Glycosides with Antibacterial Activity from Soft Coral Lemnalia bournei
by Xiao Han, Huiting Wang, Bing Li, Xiaoyi Chen, Te Li, Xia Yan, Han Ouyang, Wenhan Lin and Shan He
Mar. Drugs 2024, 22(4), 157; https://doi.org/10.3390/md22040157 (registering DOI) - 29 Mar 2024
Abstract
Five new biflorane-type diterpenoids, biofloranates E–I (15), and two new bicyclic diterpene glycosides, lemnaboursides H–I (67), along with the known lemnabourside, were isolated from the South China Sea soft coral Lemnalia bournei. Their chemical [...] Read more.
Five new biflorane-type diterpenoids, biofloranates E–I (15), and two new bicyclic diterpene glycosides, lemnaboursides H–I (67), along with the known lemnabourside, were isolated from the South China Sea soft coral Lemnalia bournei. Their chemical structures and stereochemistry were determined based on extensive spectroscopic methods, including time-dependent density functional theory (TDDFT) ECD calculations, as well as a comparison of them with the reported values. The antibacterial activities of the isolated compounds were evaluated against five pathogenic bacteria, and all of these diterpenes and diterpene glycosides showed antibacterial activities against Staphylococcus aureus and Bacillus subtilis, with MICs ranging from 4 to 64 µg/mL. In addition, these compounds did not exhibit noticeable cytotoxicities on A549, Hela, and HepG2 cancer cell lines, at 20 μM. Full article
(This article belongs to the Special Issue Bioactive Compounds from Soft Corals and Their Derived Microorganisms)
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36 pages, 3402 KiB  
Article
Strain Monitoring of Concrete Using Carbon Black-Based Smart Coatings
by Gabriele Milone, Christos Vlachakis, Jean-Marc Tulliani and Abir Al-Tabbaa
Materials 2024, 17(7), 1577; https://doi.org/10.3390/ma17071577 (registering DOI) - 29 Mar 2024
Abstract
Given the challenges we face of an ageing infrastructure and insufficient maintenance, there is a critical shift towards preventive and predictive maintenance in construction. Self-sensing cement-based materials have drawn interest in this sector due to their high monitoring performance and durability compared to [...] Read more.
Given the challenges we face of an ageing infrastructure and insufficient maintenance, there is a critical shift towards preventive and predictive maintenance in construction. Self-sensing cement-based materials have drawn interest in this sector due to their high monitoring performance and durability compared to electronic sensors. While bulk applications have been well-discussed within this field, several challenges exist in their implementation for practical applications, such as poor workability and high manufacturing costs at larger volumes. This paper discusses the development of smart carbon-based cementitious coatings for strain monitoring of concrete substrates under flexural loading. This work presents a physical, electrical, and electromechanical investigation of sensing coatings with varying carbon black (CB) concentrations along with the geometric optimisation of the sensor design. The optimal strain-sensing performance, 55.5 ± 2.7, was obtained for coatings with 2 wt% of conductive filler, 3 mm thickness, and a gauge length of 60 mm. The results demonstrate the potential of applying smart coatings with carbon black addition for concrete strain monitoring. Full article
15 pages, 371 KiB  
Article
Characterization of Vestibular Phenotypes in Patients with Genetic Hearing Loss
by Ji Hyuk Han, Seong Hoon Bae, Sun Young Joo, Jung Ah Kim, Se Jin Kim, Seung Hyun Jang, Dongju Won, Heon Yung Gee, Jae Young Choi, Jinsei Jung and Sung Huhn Kim
J. Clin. Med. 2024, 13(7), 2001; https://doi.org/10.3390/jcm13072001 (registering DOI) - 29 Mar 2024
Abstract
The vestibular phenotypes of patients with genetic hearing loss are poorly understood. Methods: we performed genetic testing including exome sequencing and vestibular function tests to investigate vestibular phenotypes and functions in patients with genetic hearing loss. Results: Among 627 patients, 143 (22.8%) had [...] Read more.
The vestibular phenotypes of patients with genetic hearing loss are poorly understood. Methods: we performed genetic testing including exome sequencing and vestibular function tests to investigate vestibular phenotypes and functions in patients with genetic hearing loss. Results: Among 627 patients, 143 (22.8%) had vestibular symptoms. Genetic variations were confirmed in 45 (31.5%) of the 143 patients. Nineteen deafness genes were linked with vestibular symptoms; the most frequent genes in autosomal dominant and recessive individuals were COCH and SLC26A4, respectively. Vestibular symptoms were mostly of the vertigo type, recurrent, and persisted for hours in the genetically confirmed and unconfirmed groups. Decreased vestibular function in the caloric test, video head impulse test, cervical vestibular-evoked myogenic potential, and ocular vestibular-evoked myogenic potential was observed in 42.0%, 16.3%, 57.8%, and 85.0% of the patients, respectively. The caloric test revealed a significantly higher incidence of abnormal results in autosomal recessive individuals than in autosomal dominant individuals (p = 0.011). The genes, including SLC26A4, COCH, KCNQ4, MYH9, NLRP3, EYA4, MYO7A, MYO15A, and MYH9, were heterogeneously associated with abnormalities in the vestibular function test. Conclusions: In conclusion, diverse vestibular symptoms are commonly concomitant with genetic hearing loss and are easily overlooked. Full article
(This article belongs to the Special Issue Clinical Insights into Vestibular Disorders)

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