The 2023 MDPI Annual Report has
been released!
 
31 pages, 9940 KiB  
Article
Combining Transformer, Convolutional Neural Network, and Long Short-Term Memory Architectures: A Novel Ensemble Learning Technique That Leverages Multi-Acoustic Features for Speech Emotion Recognition in Distance Education Classrooms
by Eman Abdulrahman Alkhamali, Arwa Allinjawi and Rehab Bahaaddin Ashari
Appl. Sci. 2024, 14(12), 5050; https://doi.org/10.3390/app14125050 (registering DOI) - 10 Jun 2024
Abstract
Speech emotion recognition (SER) is a technology that can be applied to distance education to analyze speech patterns and evaluate speakers’ emotional states in real time. It provides valuable insights and can be used to enhance students’ learning experiences by enabling the assessment [...] Read more.
Speech emotion recognition (SER) is a technology that can be applied to distance education to analyze speech patterns and evaluate speakers’ emotional states in real time. It provides valuable insights and can be used to enhance students’ learning experiences by enabling the assessment of their instructors’ emotional stability, a factor that significantly impacts the effectiveness of information delivery. Students demonstrate different engagement levels during learning activities, and assessing this engagement is important for controlling the learning process and improving e-learning systems. An important aspect that may influence student engagement is their instructors’ emotional state. Accordingly, this study used deep learning techniques to create an automated system for recognizing instructors’ emotions in their speech when delivering distance learning. This methodology entailed integrating transformer, convolutional neural network, and long short-term memory architectures into an ensemble to enhance the SER. Feature extraction from audio data used Mel-frequency cepstral coefficients; chroma; a Mel spectrogram; the zero-crossing rate; spectral contrast, centroid, bandwidth, and roll-off; and the root-mean square, with subsequent optimization processes such as adding noise, conducting time stretching, and shifting the audio data. Several transformer blocks were incorporated, and a multi-head self-attention mechanism was employed to identify the relationships between the input sequence segments. The preprocessing and data augmentation methodologies significantly enhanced the precision of the results, with accuracy rates of 96.3%, 99.86%, 96.5%, and 85.3% for the Ryerson Audio–Visual Database of Emotional Speech and Song, Berlin Database of Emotional Speech, Surrey Audio–Visual Expressed Emotion, and Interactive Emotional Dyadic Motion Capture datasets, respectively. Furthermore, it achieved 83% accuracy on another dataset created for this study, the Saudi Higher-Education Instructor Emotions dataset. The results demonstrate the considerable accuracy of this model in detecting emotions in speech data across different languages and datasets. Full article
(This article belongs to the Special Issue Computer Vision and AI for Interactive Robotics)
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18 pages, 32602 KiB  
Article
Three-Dimensional Thermo–Chemo–Mechanical Coupled Curing Analysis for the Filament Wound Composite Shell
by Linjiao Lu, Shengsheng Huan, Mengkai Lu, Tao Shen, Yanhui Tian, Jianying Hu, Jianke Du and Minghua Zhang
Polymers 2024, 16(12), 1643; https://doi.org/10.3390/polym16121643 (registering DOI) - 10 Jun 2024
Abstract
Carbon fiber resin-based composite materials are widely employed in the manufacturing of composite shells. During the curing process, the temperature gradients and cure degree gradients make it easy to generate thermal strains in both carbon fibers and resin, with the resin experiencing cure [...] Read more.
Carbon fiber resin-based composite materials are widely employed in the manufacturing of composite shells. During the curing process, the temperature gradients and cure degree gradients make it easy to generate thermal strains in both carbon fibers and resin, with the resin experiencing cure shrinkage strain due to the curing reaction, ultimately leading to residual stresses and strains. In this paper, a three-dimensional thermo–chemo–mechanical coupled curing model of the composite shell was established based on a resin test, and the changes of temperature, curing degree, residual stress, and strain during the solidification of the composite shell were investigated. First, the curing property parameters and elastic modulus of HCM-2184 resin were obtained through a curing dynamic test and a tensile test. Then, considering the heat release and shrinkage reaction of solidification, a coupled thermo–chemo–mechanical curing model was developed with the CHILE (α) elastic model, and the curing process of the composite shell was simulated numerically. The results show that the resin used in the test belongs to the autocatalytic reaction. For thin composite shells, the heat accumulation inside the shell during curing is not obvious. During the curing process, the curing shrinkage behavior of the resin is an important factor for the generation of residual stress and residual strain. Full article
(This article belongs to the Section Polymer Composites and Nanocomposites)
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21 pages, 2546 KiB  
Article
Multizone Modeling for Hybrid Thermal Energy Storage
by Sarah Jäger, Valerie Pabst and Peter Renze
Energies 2024, 17(12), 2854; https://doi.org/10.3390/en17122854 (registering DOI) - 10 Jun 2024
Abstract
This study presents a one-dimensional mathematical model developed to simulate multi-zone thermal storage systems using phase change materials (PCMs). The model enables precise analysis of temperature distribution in the layered storage based on several PCM configurations and properties. It is distinguished by its [...] Read more.
This study presents a one-dimensional mathematical model developed to simulate multi-zone thermal storage systems using phase change materials (PCMs). The model enables precise analysis of temperature distribution in the layered storage based on several PCM configurations and properties. It is distinguished by its adaptability to various tank geometries and the number of PCM capsules, enabling its application under diverse operating conditions. By simplifying the implementation of heat transfer processes that depend on the shape of the capsule and the thermal properties of the PCM, the computation time can be reduced to a level that makes simulations over longer periods feasible. Experimental validation confirmed the accuracy of the model, with deviations below 6%, underscoring its practical applicability. The study demonstrates that individual layering in the storage tank can be achieved by filling it with PCMs of different melting points without compromising the maximum storage capacity. It is shown that including a PCM layer can maintain the outlet temperature 20% longer while storing 14% more energy. The results point out the model’s potential to improve the performance of thermal storage systems through targeted PCM layer configurations. The model serves as the basis for the planning and optimization of these systems. Full article
(This article belongs to the Special Issue Highly Efficient Thermal Energy Storage (TES) Technologies)
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9 pages, 1458 KiB  
Technical Note
Preliminary Verification of the PHITS Code Applicability to Conversion Efficiency Calculation of Direct Charge Nuclear Battery
by Hiroki Takezawa, Ryuma Kigeuchi, Hibiki Umeda, Fumihiro Tamura, Yuki Uchida and Kikuchi Takashi
Machines 2024, 12(6), 395; https://doi.org/10.3390/machines12060395 (registering DOI) - 10 Jun 2024
Abstract
A direct charge nuclear battery, or DCNB, is one of the nuclear batteries based on direct energy conversion and is characterized by exceptional high voltage generation and conversion efficiency higher than other nuclear batteries. For studying potential applications of DCNB, a preliminary estimation [...] Read more.
A direct charge nuclear battery, or DCNB, is one of the nuclear batteries based on direct energy conversion and is characterized by exceptional high voltage generation and conversion efficiency higher than other nuclear batteries. For studying potential applications of DCNB, a preliminary estimation of DCNB electrical power and performance is required; hence, conversion efficiency analysis is crucial. For preliminary verification purposes, an ideal DCNB conversion efficiency was calculated under the simplified electron transport model by using the general-purpose Monte Carlo particle transport calculation code PHITS. The result was compared with a reference experimental efficiency for a T-loaded parallel plate DCNB, and the resulting relative error was approximately 12%. Considering the relative error of 20% or less in DCNB conversion efficiency shown by preceding studies, the resulting error was comparable, and it was concluded that the PHITS code is sufficiently applicable to DCNB conversion efficiency analysis. Full article
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12 pages, 2683 KiB  
Article
Retrospective Correlation of the Circulation Time of Test Bolus Injections in MR Angiography and Cardiac Function
by David F. Möller, Borut Mohorko, Theresia E. Aschauer, Tobias Schwager and Manuela A. Aschauer
J. Vasc. Dis. 2024, 3(2), 212-223; https://doi.org/10.3390/jvd3020017 (registering DOI) - 10 Jun 2024
Abstract
This retrospective study examines 248 test bolus examinations preceding contrast-enhanced magnetic resonance angiography (CE-MRA) to extract clinically relevant data for critical limb ischemia (CLI) management. The method involved a retrospective review of test bolus exams, analysing 60 graphs for time to peak (TTP), [...] Read more.
This retrospective study examines 248 test bolus examinations preceding contrast-enhanced magnetic resonance angiography (CE-MRA) to extract clinically relevant data for critical limb ischemia (CLI) management. The method involved a retrospective review of test bolus exams, analysing 60 graphs for time to peak (TTP), full-width half-maximum (FWHM) time, and time to continual rise in signal intensity. These values were correlated with heart function parameters (ejection fraction, ASA classification, Lee index, and MET score). The results indicate a mean TTP of 31.2 ± 7.3 s, showing a correlation between the ejection fraction and ASA classification. Patients with atrial fibrillation exhibited prolonged TTP compared to those without. Despite population heterogeneity, these findings facilitate risk stratification for limb-saving interventions in CLI. TTP emerges as a potential clinical cardiovascular parameter and a risk factor for vascular interventions. Given the variation in injection protocols across centres, this study underscores the importance of precise bolus arrival time documentation for future multicentre studies. Full article
(This article belongs to the Section Peripheral Vascular Diseases)
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10 pages, 778 KiB  
Article
Determination of Volatile Organic Compounds in Some Epipactis, Neottia, and Limodorum Orchids Growing in Basilicata (Southern Italy)
by Maurizio D’Auria, Richard Lorenz, Rocco Racioppi and Vito Antonio Romano
Compounds 2024, 4(2), 366-375; https://doi.org/10.3390/compounds4020022 (registering DOI) - 10 Jun 2024
Abstract
SPME analysis of the scent of Epipactis microphylla showed the presence of limonene as the main component of the scent. Other components were 2,4,4,6,6,8,8-heptamethyl-1-nonene, pentadecane, and heptadecane. The scent of Epipactis palustris was characterized by pentadecane, 2,4,4,6,6,8,8-heptamethyl-1-nonene, and heptadecane. The scent of Neottia [...] Read more.
SPME analysis of the scent of Epipactis microphylla showed the presence of limonene as the main component of the scent. Other components were 2,4,4,6,6,8,8-heptamethyl-1-nonene, pentadecane, and heptadecane. The scent of Epipactis palustris was characterized by pentadecane, 2,4,4,6,6,8,8-heptamethyl-1-nonene, and heptadecane. The scent of Neottia nidus avis showed the presence of kaur-16-ene as the main component of the scent. Other components were heinecosane, tetradecane, pentadecane, hexadecane, heptadecane, and 5,9,13-trimethyl-4,8,12-tetradecanal. The scent of Neottia ovata is due to pentadecane, hexadecane, and heptadecane. The scent of Limodorum abortivum showed the presence of 2,4,4,6,6,8,8-heptamethyl-1-nonene, pentadecane, hexadecane, heptadecane, and 2-(dodecyloxy)-ethanol. Full article
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36 pages, 5054 KiB  
Article
Graphical Insight: Revolutionizing Seizure Detection with EEG Representation
by Muhammad Awais, Samir Brahim Belhaouari and Khelil Kassoul
Biomedicines 2024, 12(6), 1283; https://doi.org/10.3390/biomedicines12061283 (registering DOI) - 10 Jun 2024
Abstract
Epilepsy is characterized by recurring seizures that result from abnormal electrical activity in the brain. These seizures manifest as various symptoms including muscle contractions and loss of consciousness. The challenging task of detecting epileptic seizures involves classifying electroencephalography (EEG) signals into ictal (seizure) [...] Read more.
Epilepsy is characterized by recurring seizures that result from abnormal electrical activity in the brain. These seizures manifest as various symptoms including muscle contractions and loss of consciousness. The challenging task of detecting epileptic seizures involves classifying electroencephalography (EEG) signals into ictal (seizure) and interictal (non-seizure) classes. This classification is crucial because it distinguishes between the states of seizure and seizure-free periods in patients with epilepsy. Our study presents an innovative approach for detecting seizures and neurological diseases using EEG signals by leveraging graph neural networks. This method effectively addresses EEG data processing challenges. We construct a graph representation of EEG signals by extracting features such as frequency-based, statistical-based, and Daubechies wavelet transform features. This graph representation allows for potential differentiation between seizure and non-seizure signals through visual inspection of the extracted features. To enhance seizure detection accuracy, we employ two models: one combining a graph convolutional network (GCN) with long short-term memory (LSTM) and the other combining a GCN with balanced random forest (BRF). Our experimental results reveal that both models significantly improve seizure detection accuracy, surpassing previous methods. Despite simplifying our approach by reducing channels, our research reveals a consistent performance, showing a significant advancement in neurodegenerative disease detection. Our models accurately identify seizures in EEG signals, underscoring the potential of graph neural networks. The streamlined method not only maintains effectiveness with fewer channels but also offers a visually distinguishable approach for discerning seizure classes. This research opens avenues for EEG analysis, emphasizing the impact of graph representations in advancing our understanding of neurodegenerative diseases. Full article
(This article belongs to the Special Issue New Insights into Motor Neuron Diseases)
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36 pages, 11751 KiB  
Review
Ferroelectric Material in Triboelectric Nanogenerator
by Zhiyu Zhang, Tong Wu, Enqi Sun, Yahui Chen and Ning Wang
Materials 2024, 17(12), 2834; https://doi.org/10.3390/ma17122834 (registering DOI) - 10 Jun 2024
Abstract
Ferroelectric materials, with their spontaneous electric polarization, are renewing research enthusiasm for their deployment in high-performance micro/nano energy harvesting devices such as triboelectric nanogenerators (TENGs). Here, the introduction of ferroelectric materials into the triboelectric interface not only significantly enhances the energy harvesting efficiency, [...] Read more.
Ferroelectric materials, with their spontaneous electric polarization, are renewing research enthusiasm for their deployment in high-performance micro/nano energy harvesting devices such as triboelectric nanogenerators (TENGs). Here, the introduction of ferroelectric materials into the triboelectric interface not only significantly enhances the energy harvesting efficiency, but also drives TENGs into the era of intelligence and integration. The primary objective of the following paper is to tackle the newest innovations in TENGs based on ferroelectric materials. For this purpose, we begin with discussing the fundamental idea and then introduce the current progress with TENGs that are built on the base of ferroelectric materials. Various strategies, such as surface engineering, either in the micro or nano scale, are discussed, along with the environmental factors. Although our focus is on the enhancement of energy harvesting efficiency and output power density by utilizing ferroelectric materials, we also highlight their incorporation in self-powered electronics and sensing systems, where we analyze the most favorable and currently accessible options in attaining device intelligence and multifunctionality. Finally, we present a detailed outlook on TENGs that are based on ferroelectric materials. Full article
(This article belongs to the Special Issue Nanoarchitectonics in Materials Science)
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15 pages, 20489 KiB  
Article
Contribution of EBSD for the Microstructural Study of Archaeological Iron Alloy Artefacts from the Archaeological Site of Loiola (Biscay, Northern Spain)
by Céline Rémazeilles, Maria Cruz Zuluaga, Haizea Portillo-Blanco, Egle Conforto, Abdelali Oudriss, Luis Àngel Ortega, Ainhoa Alonso-Olazabal and Juan José Cepeda-Ocampo
Heritage 2024, 7(6), 3179-3193; https://doi.org/10.3390/heritage7060150 (registering DOI) - 10 Jun 2024
Abstract
Iron palaeometallurgy was carried out on three artefacts, classified as nails and excavated from the archaeological site of Loiola (La Arboleda, Biscay, northern Spain), to investigate Roman manufacturing techniques. Energy Dispersive Spectroscopy (EDS) coupled with Environmental Scanning Electron Microscopy (ESEM) and micro-Raman spectroscopy [...] Read more.
Iron palaeometallurgy was carried out on three artefacts, classified as nails and excavated from the archaeological site of Loiola (La Arboleda, Biscay, northern Spain), to investigate Roman manufacturing techniques. Energy Dispersive Spectroscopy (EDS) coupled with Environmental Scanning Electron Microscopy (ESEM) and micro-Raman spectroscopy were used to obtain elemental composition and structural characterization of mineral phases. Metallurgical properties and crystallographic texture were studied by combining microscopic methods such as optical microscopy (OM), Electron Backscatter Diffraction realized in environmental mode (EBSD) and measurements of local Vickers microhardness. The three artefacts had different microstructures, distinguished by a large gradient of carbon content, although important segregations (inclusions) were observed in all of them. Two pearlite-rich artefacts showed a high density of structural defects (geometrically necessary dislocations and large crystallographic orientation gradients in pearlitic ferrite, curved pearlitic cementite) resulting from a high level of plastic deformation that occurred during the manufacturing process. The third artefact consisted of pure ferrite without structural defects. This one was clearly manufactured differently from the two others, so it probably had another functionality. Full article
(This article belongs to the Special Issue Conservation and Restoration of Metal Artifacts)
14 pages, 3642 KiB  
Article
Comparison of the Climate Change Tolerance of Native and Non-Native Species Used or Potentially Used as Ornamentals in Mediterranean Areas
by Pilar Soriano, Reyes Mora, Elena Estrelles and M. Isabel Martínez-Nieto
Horticulturae 2024, 10(6), 620; https://doi.org/10.3390/horticulturae10060620 (registering DOI) - 10 Jun 2024
Abstract
As a consequence of climate change, temperature and rainfall regimes are being modified, threatening the survival of the current gardening concept in many areas of the world. This situation highlights the need to investigate the potential of other species, especially in more sensitive [...] Read more.
As a consequence of climate change, temperature and rainfall regimes are being modified, threatening the survival of the current gardening concept in many areas of the world. This situation highlights the need to investigate the potential of other species, especially in more sensitive areas such as the Mediterranean Basin. The aim of this research is to study the resilience of adapted species to promote sustainable gardening. To achieve this, seven species belonging to three families (Amaranthaceae, Lamiaceae and Asteraceae) used or potentially used as ornamentals were selected to compare their tolerance at the germinative stage to different levels of temperature (10 °C to 35 °C) and water stress created by PEG 6000 (−0.10 MPa to −2.5 MPa). Germination percentage, mean germination time, base temperature, thermal time, base water potential and hydrotime were calculated. The results showed a good response to high temperature and low osmotic potential in most of the species, and germination even increased under certain stress levels. Salsola oppositifolia presented by far the best results in terms of germination under high-water-stress conditions and the second best at high temperatures. The extraordinary response of Celosia argentea, an alien species, highlighted the risk of it becoming an invasive species. Full article
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30 pages, 9402 KiB  
Review
Design Principles and Development Status of Flexible Integrated Thin and Lightweight Zinc-Ion Batteries
by Xuxian Liu, Yongchang Jiang, Yaqun Wang and Lijia Pan
Batteries 2024, 10(6), 200; https://doi.org/10.3390/batteries10060200 (registering DOI) - 10 Jun 2024
Abstract
The rapid advancement of wearable devices and flexible electronics has spurred an increasing need for high-performance, thin, lightweight, and flexible energy storage devices. In particular, thin and lightweight zinc-ion batteries require battery materials that possess exceptional flexibility and mechanical stability to accommodate complex [...] Read more.
The rapid advancement of wearable devices and flexible electronics has spurred an increasing need for high-performance, thin, lightweight, and flexible energy storage devices. In particular, thin and lightweight zinc-ion batteries require battery materials that possess exceptional flexibility and mechanical stability to accommodate complex deformations often encountered in flexible device applications. Moreover, the development of compact and thin battery structures is essential to minimize the overall size and weight while maintaining excellent electrochemical performance, including high energy density, long cycle life, and stable charge/discharge characteristics, to ensure their versatility across various applications. Researchers have made significant strides in enhancing the battery’s performance by optimizing crucial components such as electrode materials, electrolytes, separators, and battery structure. This review provides a comprehensive analysis of the design principles essential for achieving thinness in zinc-ion batteries, along with a summary of the preparation methods and potential applications of these batteries. Moreover, it delves into the challenges associated with achieving thinness in zinc-ion batteries and proposes effective countermeasures to address these hurdles. This review concludes by offering insights into future developments in this field, underscoring the continual advancements and innovations that can be expected. Full article
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24 pages, 13251 KiB  
Article
Analysis of Spatial and Temporal Distribution and Changes in Extreme Climate Events in Northwest China from 1960 to 2021: A Case Study of Xinjiang
by Yang Yang and Wei Chang
Sustainability 2024, 16(12), 4960; https://doi.org/10.3390/su16124960 (registering DOI) - 10 Jun 2024
Abstract
Xinjiang, as a climate-sensitive region in Northwest China, holds significant importance in studying extreme climate events for agricultural production and socioeconomic development. Using data spanning from 1960 to 2021 from 52 meteorological stations across Xinjiang, encompassing 23 indices of extreme climate events, the [...] Read more.
Xinjiang, as a climate-sensitive region in Northwest China, holds significant importance in studying extreme climate events for agricultural production and socioeconomic development. Using data spanning from 1960 to 2021 from 52 meteorological stations across Xinjiang, encompassing 23 indices of extreme climate events, the 5-year moving average, linear trend fitting, and inverse distance weighting (IDW) are used to analyze the distribution patterns and temporal changes in extreme climatic phenomena within the region. The results indicate that, over the period from 1960 to 2021, the Amplitude Temperature Index, Heat Index, and Warm Spell Duration Index in Xinjiang exhibited a marked increasing trend, whereas the Cold Index and Cold Spell Duration Index displayed a significant decreasing trend. The range of changes in the extreme temperature indices from 1990 to 2021 is higher than that of 1960 to 1989. The areas with high values of amplitude temperature extreme indices are primarily concentrated in the southern part, while the areas with high values of cold indices are mainly distributed in the northern part. The upward/downward trends all account for over 80.00% of the entire region. The precipitation scale indices, precipitation day indices, intense precipitation index, and extreme precipitation index all showed a significant growth trend from 1960 to 2021, and the range of change in the extreme precipitation indices from 1990 to 2021 was lower than that from 1960 to 1989. Furthermore, areas with high precipitation values and regions with high trend values of climate tendency are predominantly concentrated in the northern and western parts of Xinjiang, with over 71.00% of the entire region experiencing an upward trend. The research results provide theoretical foundations for formulating climate risk strategies in the northwest region of China. Full article
25 pages, 9727 KiB  
Article
Low-Sidelobe Imaging Method Utilizing Improved Spatially Variant Apodization for Forward-Looking Sonar
by Lu Yan, Juan Yang, Feng Xu and Shengchun Piao
Remote Sens. 2024, 16(12), 2100; https://doi.org/10.3390/rs16122100 (registering DOI) - 10 Jun 2024
Abstract
For two-dimensional forward-looking sonar imaging, high sidelobes significantly degrade the quality of sonar images. The cosine window function weighting method is often applied to suppress the sidelobe levels in the angular and range dimensions, at the expense of the main lobe resolutions. Therefore, [...] Read more.
For two-dimensional forward-looking sonar imaging, high sidelobes significantly degrade the quality of sonar images. The cosine window function weighting method is often applied to suppress the sidelobe levels in the angular and range dimensions, at the expense of the main lobe resolutions. Therefore, an improved spatially variant apodization imaging method for forward-looking sonar is proposed, to reduce sidelobes without degrading the main lobe resolution in angular-range dimensions. The proposed method is a nonlinear postprocessing operation in which the raw complex-valued sonar image produced by a conventional beamformer and matched filter is weighted by a spatially variant coefficient. To enhance the robustness of the spatially variant apodization approach, the array magnitude and phase errors are calibrated to prevent the occurrence of beam sidelobe increase prior to beamforming operations. The analyzed results of numerical simulations and a lake experiment demonstrate that the proposed method can greatly reduce the sidelobes to approximately −40 dB, while the main lobe width remains unchanged. Moreover, this method has an extremely simple computational process. Full article
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15 pages, 3005 KiB  
Article
Disintegrated Waste-Activated Sludge (NO2/FNA Method) as a Source of Carbon for Denitrification in the Mainstream of a WWTP
by Dorota Szypulska, Kamil Janiak, Bartosz Zięba, Anna Wizimirska, Marek Mołczan, Sławomir Szerzyna and Renata Tomczak-Wandzel
Resources 2024, 13(6), 80; https://doi.org/10.3390/resources13060080 (registering DOI) - 10 Jun 2024
Abstract
The deficiency of readily biodegradable organic carbon can be a significant limitation to effective nitrogen removal during wastewater denitrification. Waste-activated sludge (WAS) is a source of carbon produced directly at wastewater treatment plants (WWTPs). Raw WAS has a large molecular weight and complex [...] Read more.
The deficiency of readily biodegradable organic carbon can be a significant limitation to effective nitrogen removal during wastewater denitrification. Waste-activated sludge (WAS) is a source of carbon produced directly at wastewater treatment plants (WWTPs). Raw WAS has a large molecular weight and complex chemical structure molecules that are not easily available for microorganisms. In this study, easily biodegradable organic fractions were released using pH control and/or nitrites and nitric acid (NO2/FNA). The obtained results indicated that WAS can be a sufficient carbon source for denitrification in WWTPs that are at risk of minor effluent violations. The implementation of WAS disintegration with the use of pH control and NO2/FNA allowed for the denitrification of an additional 0.5 and 0.8 mgN-NO3/L. WAS disintegration, besides being a source of carbon generation, reduces the volume of sludge and leads to the implementation of a closed-loop system. Full article
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24 pages, 3027 KiB  
Article
Metabolic Changes in Pseudomonas oleovorans Isolated from Contaminated Construction Material Exposed to Varied Biocide Treatments
by Muatasem Latif Ali, Lionel Ferrieres, Jana Jass and Tuulia Hyötyläinen
Metabolites 2024, 14(6), 326; https://doi.org/10.3390/metabo14060326 (registering DOI) - 10 Jun 2024
Abstract
Biocide resistance poses a significant challenge in industrial processes, with bacteria like Pseudomonas oleovorans exhibiting intrinsic resistance to traditional antimicrobial agents. In this study, the impact of biocide exposure on the metabolome of two P. oleovorans strains, namely, P. oleovorans P4A, isolated from [...] Read more.
Biocide resistance poses a significant challenge in industrial processes, with bacteria like Pseudomonas oleovorans exhibiting intrinsic resistance to traditional antimicrobial agents. In this study, the impact of biocide exposure on the metabolome of two P. oleovorans strains, namely, P. oleovorans P4A, isolated from contaminated coating material, and P. oleovorans 1045 reference strain, were investigated. The strains were exposed to 2-Methylisothiazol-3(2H)-one (MI) MIT, 1,2-Benzisothiazol-3(2H)-one (BIT), and 5-chloro-2-methyl-isothiazol-3-one (CMIT) at two different sub-inhibitory concentrations and the lipids and polar and semipolar metabolites were analyzed by ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry UPLC–Q–TOF/MS. Exposure to the BIT biocide induced significant metabolic modifications in P. oleovorans. Notable changes were observed in lipid and metabolite profiles, particularly in phospholipids, amino acid metabolism, and pathways related to stress response and adaptation. The 1045 strain showed more pronounced metabolic alterations than the P4A strain, suggesting potential implications for lipid, amino acid metabolism, energy metabolism, and stress adaptation. Improving our understanding of how different substances interact with bacteria is crucial for making antimicrobial chemicals more effective and addressing the challenges of resistance. We observed that different biocides trigged significantly different metabolic responses in these strains. Our study shows that metabolomics can be used as a tool for the investigation of metabolic mechanisms underlying biocide resistance, and thus in the development of targeted biocides. This in turn can have implications in combating biocide resistance in bacteria such as P. oleovorans. Full article
(This article belongs to the Section Microbiology and Ecological Metabolomics)
28 pages, 30608 KiB  
Article
Cracking Methods for Testing of Self-Healing Concrete: An Experimental Approach
by João Miguel Peres Medeiros and Luigi Di Sarno
Buildings 2024, 14(6), 1744; https://doi.org/10.3390/buildings14061744 (registering DOI) - 10 Jun 2024
Abstract
With the advent of new sustainable construction materials, self-healing concrete has been used and tested in the last decade, raising the question of the efficacy of said mechanisms to prevent water permeation after crack formation. Thus, new novel mechanical methodologies have been introduced [...] Read more.
With the advent of new sustainable construction materials, self-healing concrete has been used and tested in the last decade, raising the question of the efficacy of said mechanisms to prevent water permeation after crack formation. Thus, new novel mechanical methodologies have been introduced to induce controlled cracks in concrete specimens to improve the standardisation and effectiveness of permeability tests. This research explores those new mechanical techniques to create consistent and reproducible crack patterns, crucial for assessing the efficacy of self-healing mechanisms in concrete. This study systematically evaluates how different crack configurations influence the self-healing ability of the material. Findings from this research are expected to aid in refining testing protocols and to contribute significantly to the field of material science within civil engineering by demonstrating the potential of self-healing concrete to revolutionise building practices. Full article
(This article belongs to the Collection Advanced Concrete Materials in Construction)
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13 pages, 970 KiB  
Article
Assessment of Landslide Susceptibility in the Moxi Tableland of China by Using a Combination of Deep-Learning and Factor-Refinement Methods
by Zonghan He, Wenjun Zhang, Jialun Cai, Jing Fan, Haoming Xu, Hui Feng, Xinlong Luo and Zhouhang Wu
Appl. Sci. 2024, 14(12), 5042; https://doi.org/10.3390/app14125042 (registering DOI) - 10 Jun 2024
Abstract
Abstract: Precisely assessing the vulnerability of landslides is essential for effective risk assessment. The findings from such assessments will undoubtedly be in high demand, providing a solid scientific foundation for a range of critical initiatives aimed at disaster prevention and control. In the [...] Read more.
Abstract: Precisely assessing the vulnerability of landslides is essential for effective risk assessment. The findings from such assessments will undoubtedly be in high demand, providing a solid scientific foundation for a range of critical initiatives aimed at disaster prevention and control. In the research, authors set the ancient core district of Sichuan Moxi Ancient Town as the research object; they conduct and give the final result of the geological survey. Fault influences are commonly utilized as key markers for delineating strata in the field of stratigraphy, and the slope distance, slope angle, slope aspect, elevation, terrain undulation, plane curvature, profile curvature, mean curvature, relative elevation, land use type, surface roughness, water influence, distance of the catchment, cumulative water volume, and the Normalized Vegetation Index (NDVI) are used along roads to calculate annual rainfall. With the purpose of the establishment of the evaluation system, there are 17 factors selected in total. Through the landslide-susceptibility assessment by the coupled models of DNN-I-SVM and DNN-I-LR nine factors had been selected; it was found that the Area Under the Curve (AUC) value of the Receiver Operating Characteristic Curve (ROC) was high, and the accuracy of the model is relatively high. The coupler, DNN-I-LR, gives 0.875 of an evaluation accuracy of AUC, higher than DNN-I-SVM, which yielded 0.860. It is necessary to note that, in this region, compared to the DNN-I-SVM model, the DNN-I-LR coupling model has better fitting and prediction abilities. Full article
15 pages, 912 KiB  
Review
Exploring the Potential Use of Natural Products Together with Alkalization in Cancer Therapy
by Masahide Isowa, Reo Hamaguchi, Ryoko Narui, Hiromasa Morikawa, Toshihiro Okamoto and Hiromi Wada
Pharmaceutics 2024, 16(6), 787; https://doi.org/10.3390/pharmaceutics16060787 (registering DOI) - 10 Jun 2024
Abstract
Cancer treatment is a significant focus in medicine, owing to the increasing global incidence of cancers. Patients with advanced cancers that do not respond to conventional therapies have limited options and an unfavorable prognosis. Consequently, researchers are investigating complementary approaches to conventional treatments. [...] Read more.
Cancer treatment is a significant focus in medicine, owing to the increasing global incidence of cancers. Patients with advanced cancers that do not respond to conventional therapies have limited options and an unfavorable prognosis. Consequently, researchers are investigating complementary approaches to conventional treatments. One such approach is alkalization therapy, which aims to neutralize the acidic tumor microenvironment (TME) by increasing its pH level. The acidic TME promotes inflammation, tumor progression, and drug resistance. Alkalization therapy has been demonstrated to be effective for various cancers. In addition, natural products, such as triterpenoids, parthenolides, fulvic acid, Taxus yunnanensis, and apple pectin have the potential to alleviate symptoms, maintain physical fitness, and improve treatment outcomes of cancer patients through their anti-inflammatory, antioxidant, and anticancer properties. In this review, we focus on the effects of alkalization therapy and natural products on cancer. Furthermore, we present a case series of advanced cancer patients who received alkalization therapy and natural products alongside standard treatments, resulting in long-term survival. We posit that alkalization therapy together with supplementation with natural products may confer benefits to cancer patients, by mitigating the side effects of chemotherapy and complementing standard treatments. However, further research is warranted to validate these clinical findings. Full article
(This article belongs to the Special Issue Natural Products for Anticancer Application)
23 pages, 1374 KiB  
Article
Origanum dubium Boiss. (Cypriot oregano) Use for the Preservation of Fresh Spearmint Quality and Safety
by Panayiota Xylia, Antonios Chrysargyris and Nikolaos Tzortzakis
Agronomy 2024, 14(6), 1252; https://doi.org/10.3390/agronomy14061252 (registering DOI) - 10 Jun 2024
Abstract
Very little is known about the preservation and storage of fresh medicinal and aromatic plants (MAPs) and/or herbs. As with many leafy vegetables, i.e., lettuce, fresh spearmint is a very perishable product throughout the production line and requires special handling/processing. The current study [...] Read more.
Very little is known about the preservation and storage of fresh medicinal and aromatic plants (MAPs) and/or herbs. As with many leafy vegetables, i.e., lettuce, fresh spearmint is a very perishable product throughout the production line and requires special handling/processing. The current study aimed to examine the antibacterial activity of selected MAPs (Origanum dubium, Salvia fruticosa and Sideritis cypria) grown in Cyprus towards foodborne pathogens. Then, the most effective MAPs’ essential oil (EO) and hydrosol (at different doses; combination of concentration and time of dipping submerge) were tested to preserve fresh spearmint quality and safety. The results showed that O. dubium EO and hydrosol presented great in vitro antibacterial activity against four foodborne pathogens and those products were further selected for application on fresh spearmint. During sensory evaluation, it was observed that higher O. dubium EO concentrations and longer time of application resulted into a less marketable product (less acceptable with less spearmint-like aroma), while hydrosol resulted in a more marketable product even at high doses. In general, EO and hydrosol applications increased spearmint’s antioxidants (including polyphenols, flavonoids, and ascorbic acid), resulting in a product of increased nutritional value. The bacterial populations of Salmonella enterica and Listeria monocytogenes inoculated on fresh spearmint were decreased with the EO and hydrosol application doses applied, and their effects were evident even after six days of storage at 4 °C. From the findings of this study, it can be concluded that O. dubium EO and hydrosol could be a potential sanitation method for fresh spearmint preservation. Full article
13 pages, 10227 KiB  
Article
Electrochemical Polishing of Ti and Ti6Al4V Alloy in Non-Aqueous Solution of Sulfuric Acid
by Agata Kołkowska, Joanna Michalska, Rafał Zieliński and Wojciech Simka
Materials 2024, 17(12), 2832; https://doi.org/10.3390/ma17122832 (registering DOI) - 10 Jun 2024
Abstract
This paper reports the results of our study on electrochemical polishing of titanium and a Ti-based alloy using non-aqueous electrolyte. It was shown that electropolishing ensured the removal of surface defects, thereby providing surface smoothing and decreasing surface roughness. The research was conducted [...] Read more.
This paper reports the results of our study on electrochemical polishing of titanium and a Ti-based alloy using non-aqueous electrolyte. It was shown that electropolishing ensured the removal of surface defects, thereby providing surface smoothing and decreasing surface roughness. The research was conducted using samples made of titanium and Ti6Al4V alloy, as well as implant system elements: implant analog, multiunit, and healing screw. Electropolishing was carried out under a constant voltage (10–15 V) with a specified current density. The electrolyte used contained methanol and sulfuric acid. The modified surface was subjected to a thorough analysis regarding its surface morphology, chemical composition, and physicochemical properties. Scanning electron microscope images and profilometer tests of roughness confirmed significantly smoother surfaces after electropolishing. The surface profile analysis of processed samples also yielded satisfactory results, showing less imperfections than before modification. The EDX spectra showed that electropolishing does not have significant influence on the chemical composition of the samples. Full article
(This article belongs to the Special Issue Precision Manufacturing of Advanced Alloys and Composites)
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22 pages, 1132 KiB  
Guidelines
Recommendations for The Management of Patients with Hairy-Cell Leukemia and Hairy-Cell Leukemia-Like Disorders: A Work by French-Speaking Experts and French Innovative Leukemia Organization (FILO) Group
by Jérôme Paillassa, Elsa Maitre, Nadia Belarbi Boudjerra, Abdallah Madani, Raihane Benlakhal, Thomas Matthes, Eric Van Den Neste, Laura Cailly, Luca Inchiappa, Mohammed Amine Bekadja, Cécile Tomowiak and Xavier Troussard
Cancers 2024, 16(12), 2185; https://doi.org/10.3390/cancers16122185 (registering DOI) - 10 Jun 2024
Abstract
Introduction: Hairy-cell leukemia (HCL) is a rare B-cell chronic lymphoproliferative disorder (B-CLPD), whose favorable prognosis has changed with the use of purine nucleoside analogs (PNAs), such as cladribine (CDA) or pentostatin (P). However, some patients eventually relapse and over time HCL becomes resistant [...] Read more.
Introduction: Hairy-cell leukemia (HCL) is a rare B-cell chronic lymphoproliferative disorder (B-CLPD), whose favorable prognosis has changed with the use of purine nucleoside analogs (PNAs), such as cladribine (CDA) or pentostatin (P). However, some patients eventually relapse and over time HCL becomes resistant to chemotherapy. Many discoveries have been made in the pathophysiology of HCL during the last decade, especially in genomics, with the identification of the BRAFV600E mutation and cellular biology, including the importance of signaling pathways as well as tumor microenvironment. All of these new developments led to targeted treatments, especially BRAF inhibitors (BRAFis), MEK inhibitors (MEKis), Bruton’s tyrosine kinase (BTK) inhibitors (BTKis) and recombinant anti-CD22 immunoconjugates. Results: The following major changes or additions were introduced in these updated guidelines: the clinical relevance of the changes in the classification of splenic B-cell lymphomas and leukemias; the increasingly important diagnostic role of BRAFV600E mutation; and the prognostic role of the immunoglobulin (IG) variable (V) heavy chain (H) (IGHV) mutational status and repertory. We also wish to insist on the specific involvement of bones, skin, brain and/or cerebrospinal fluid (CSF) of the disease at diagnosis or during the follow-up, the novel targeted drugs (BRAFi and MEKi) used for HCL treatment, and the increasing role of minimal residual disease (MRD) assessment. Conclusion: Here we present recommendations for the diagnosis of HCL, treatment in first line and in relapsed/refractory patients as well as for HCL-like disorders including HCL variant (HCL-V)/splenic B-cell lymphomas/leukemias with prominent nucleoli (SBLPN) and splenic diffuse red pulp lymphoma (SDRPL). Full article
(This article belongs to the Section Cancer Survivorship and Quality of Life)
15 pages, 21277 KiB  
Article
Microstructure Evolution of TB18 Alloy after Thermal Treatment and the Effect of Recrystallization Texture on Mechanical Properties
by Wei Xiang, Qineng Li, Feng Zhang, Yuan Fan and Wuhua Yuan
Materials 2024, 17(12), 2828; https://doi.org/10.3390/ma17122828 (registering DOI) - 10 Jun 2024
Abstract
In industrial production, the deformation inhomogeneity after metal forging affects the mechanical properties of various parts of the forgings. The question of whether the organization and mechanical properties of β-titanium alloy can be improved by controlling the amount of forging deformation needs to [...] Read more.
In industrial production, the deformation inhomogeneity after metal forging affects the mechanical properties of various parts of the forgings. The question of whether the organization and mechanical properties of β-titanium alloy can be improved by controlling the amount of forging deformation needs to be answered. Therefore, in this paper, a new sub-stable β-Ti alloy TB 18 (Ti-5.3Cr-4.9Mo4.9V-4.3Al-0.9Nb-0.3Fe) was subjected to three different levels of deformation, as well as solid solution-aging treatments, and the variation rules of microstructure and mechanical properties were investigated. During the solid solution process, the texture evolution pattern of the TB18 alloy at low deformation (20–40%) is mainly rotational cubic texture deviated into α-fiber texture; at high deformation (60%), the main components of the deformed texture are α-fiber texture with a specific orientation of (114)<113-3>. After subsequent static recrystallization, the α-fiber texture is deviated to an α*-fiber texture, while the specific orientation (114)<113-3> can still be inherited as a major component of the recrystallized texture. The plasticity of the alloy in the normal direction (ND) after the solid solution is influenced by the existence of the <110>//ND texture, and the plasticity of the alloy in the ND direction after aging is determined by a combination of the volume fraction of the <110>//ND texture in the matrix phase and the volume fraction of [112-0]α//ND in the α phase. The results show that it is feasible to change the characteristics of the recrystallization texture of TB18 by controlling the deformation level of hot forging, thus realizing the modulation of the mechanical properties. Full article
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13 pages, 3635 KiB  
Article
Injection Pultrusion of Glass-Reinforced Epoxy: Cure Kinetics, Rheology, and Force Analysis
by Fausto Tucci, Vitantonio Esperto, Germana Pasquino and Pierpaolo Carlone
Polymers 2024, 16(12), 1642; https://doi.org/10.3390/polym16121642 (registering DOI) - 10 Jun 2024
Abstract
Pultrusion is a highly efficient continuous process to manufacture advanced fiber-reinforced composites. The injection pultrusion variant permits a higher control of the resin flow, enabling the manufacturing of a high reinforcement volume fraction. Moreover, it reduces the emission of volatile compounds that are [...] Read more.
Pultrusion is a highly efficient continuous process to manufacture advanced fiber-reinforced composites. The injection pultrusion variant permits a higher control of the resin flow, enabling the manufacturing of a high reinforcement volume fraction. Moreover, it reduces the emission of volatile compounds that are dangerous for the operators and for the working environment. The present study proposes an experimental analysis of injection pultrusion in three different operative conditions. In particular, the activity focused on the effects of the temperature setup on the thermochemical and rheological behaviors of the resin system and on the interaction between the processed materials and the pultrusion die wall. The setup of the parameters was selected to evidence the behavior of the viscous interaction during the thermoset transition to the solid state, which is particularly challenging due to the localization of high adhesive forces related to the sharp increase in resin viscosity. Microscope observations of the cross-sections were performed to discuss the effects of the process parameters. Full article
(This article belongs to the Special Issue New Progress of Polymeric Materials in Advanced Manufacturing)

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