The 2023 MDPI Annual Report has
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13 pages, 1066 KiB  
Article
Occupational Safety Assessment for Surface Mine Systems: The Case in Jordan
by Samir K. Khrais, Tamer Elia Yared, Noor Majid Saifan, Tarek H. Al-Hawari and Fikri Dweiri
Safety 2024, 10(2), 40; https://doi.org/10.3390/safety10020040 (registering DOI) - 25 Apr 2024
Abstract
Surface mining is one of the hazardous industries that have several risky operations, including transportation, treatment, and mineral extraction. To avoid the risk of disaster, it is important to evaluate safety procedures and determine expected hazards. The aim of this study is to [...] Read more.
Surface mining is one of the hazardous industries that have several risky operations, including transportation, treatment, and mineral extraction. To avoid the risk of disaster, it is important to evaluate safety procedures and determine expected hazards. The aim of this study is to develop a thorough safety evaluation model for the surface mining industry based on the analytic hierarchy process (AHP), one important multi-criteria decision-making approach. A total of 11 criteria and 36 sub-criteria that are both independent and homogeneous were involved in the decision problem. Further, a deep sensitivity analysis was conducted to assess the stability of the ranking preference. The findings indicate that four out of the eleven criteria are particularly significant. To test the model’s applicability and effectiveness, a case study was conducted involving three surface mining companies located in the north of Jordan. The results demonstrate that the model is reliable, applicable, and effective in addressing real-world problems. Full article
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14 pages, 826 KiB  
Article
Effects of Deuterium Depletion on Age-Declining Thymopoiesis In Vivo
by Nataliya V. Yaglova, Sergey S. Obernikhin, Ekaterina P. Timokhina, Dibakhan A. Tsomartova, Valentin V. Yaglov, Svetlana V. Nazimova, Elina S. Tsomartova, Marina Y. Ivanova, Elizaveta V. Chereshneva and Tatiana A. Lomanovskaya
Biomedicines 2024, 12(5), 956; https://doi.org/10.3390/biomedicines12050956 (registering DOI) - 25 Apr 2024
Abstract
The thymus provides maturation and migration of T cells to peripheral organs of immunity, where they recognize diverse antigens and maintain immunological memory and self-tolerance. The thymus is known to be involved with age and in response to stress factors. Therefore, the search [...] Read more.
The thymus provides maturation and migration of T cells to peripheral organs of immunity, where they recognize diverse antigens and maintain immunological memory and self-tolerance. The thymus is known to be involved with age and in response to stress factors. Therefore, the search for approaches to the restoration of thymopoiesis is of great interest. The present investigation was aimed at evaluating how prolonged deuterium depletion affects morphogenetic processes and the physiological transition of the thymus to age-related involution. The study was performed on 60 male Wistar rats subjected to consumption of deuterium-depleted water with a 10 ppm deuterium content for 28 days. The control rats consumed distilled water with a normal deuterium content of 150 ppm. The examination found no significant differences in body weight gain or the amount of water consumed. The exposed rats exhibited similar to control dynamics of the thymus weight but significant changes in thymic cell maturation according to cytofluorimetric analysis of thymic subpopulations. Changes in T cell production were not monotonic and differentially engaged morphogenetic processes of cell proliferation, differentiation, and migration. The reactive response to deuterium depletion was a sharp increase in the number of progenitor CD4CD8 cells and their differentiation into T cells. The compensatory reaction was inhibition of thymopoiesis with more pronounced suppression of differentiation of T-cytotoxic lymphocytes, followed by intensification of emigration of mature T cells to the bloodstream. This period lasts from 3 to 14 days, then differentiation of thymic lymphocytes is restored, later cell proliferation is activated, and finally the thymopoiesis rate exceeds the control values. The increase in the number of thymic progenitor cells after 3–4 weeks suggests consideration of deuterium elimination as a novel approach to prevent thymus involution. Full article
24 pages, 3021 KiB  
Article
Influence of TiO2 Nanoparticles on the Physical, Mechanical, and Structural Characteristics of Cementitious Composites with Recycled Aggregates
by Carmen Teodora Florean, Horațiu Vermeșan, Timea Gabor, Bogdan Viorel Neamțu, Gyorgy Thalmaier, Andreea Hegyi, Alexandra Csapai and Adrian-Victor Lăzărescu
Materials 2024, 17(9), 2014; https://doi.org/10.3390/ma17092014 (registering DOI) - 25 Apr 2024
Abstract
The aim of this study is to analyze the effect of the addition of TiO2 nanoparticles (NTs) on the physical and mechanical properties, as well as the microstructural changes, of cementitious composites containing partially substituted natural aggregates (NAs) with aggregates derived from [...] Read more.
The aim of this study is to analyze the effect of the addition of TiO2 nanoparticles (NTs) on the physical and mechanical properties, as well as the microstructural changes, of cementitious composites containing partially substituted natural aggregates (NAs) with aggregates derived from the following four recycled materials: glass (RGA), brick (RGB), blast-furnace slag (GBA), and recycled textolite waste with WEEE (waste from electrical and electronic equipment) as the primary source (RTA), in line with sustainable construction practices. The research methodology included the following phases: selection and characterization of raw materials, formulation design, experimental preparation and testing of specimens using standardized methods specific to cementitious composite mortars (including determination of apparent density in the hardened state, mechanical strength in compression, flexure, and abrasion, and water absorption by capillarity), and structural analysis using specialized techniques (scanning electron microscopy (SEM) images and energy dispersive X-ray spectroscopy (EDS)). The analysis and interpretation of the results focused primarily on identifying the effects of NT addition on the composites. Results show a decrease in density resulting from replacing NAs with recycled aggregates, particularly in the case of RGB and RTA. Conversely, the introduction of TiO2 nanoparticles resulted in a slight increase in density, ranging from 0.2% for RTA to 7.4% for samples containing NAs. Additionally, the introduction of TiO2 contributes to improved compressive strength, especially in samples containing RTA, while flexural strength benefits from a 3–4% TiO2 addition in all composites. The compressive strength ranged from 35.19 to 70.13 N/mm2, while the flexural strength ranged from 8.4 to 10.47 N/mm2. The abrasion loss varied between 2.4% and 5.71%, and the water absorption coefficient varied between 0.03 and 0.37 kg/m2m0.5, the variations being influenced by both the nature of the aggregates and the amount of NTs added. Scanning electron microscopy (SEM) images and energy dispersive X-ray spectroscopy (EDS) analysis showed that TiO2 nanoparticles are uniformly distributed in the cementitious composites, mainly forming CSH gel. TiO2 nanoparticles act as nucleating agents during early hydration, as confirmed by EDS spectra after curing. Full article
20 pages, 1049 KiB  
Article
Influencing Factors and Mechanisms of Corporate Social Responsibility Reputation under Green and Low-Carbon Transition: Evidence from Chinese Listed Companies
by Shuke Fu, Mengxia Tian, Yingchen Ge, Tingting Yao and Jiali Tian
Energies 2024, 17(9), 2044; https://doi.org/10.3390/en17092044 (registering DOI) - 25 Apr 2024
Abstract
Amid China’s pursuit of a green and low-carbon transition, corporate social responsibility (CSR) is facing new challenges. Our research delves into the influencing factors and mechanisms for CSR reputation under green and low-carbon transition and provides practical enlightenment for enterprises to achieve sustainable [...] Read more.
Amid China’s pursuit of a green and low-carbon transition, corporate social responsibility (CSR) is facing new challenges. Our research delves into the influencing factors and mechanisms for CSR reputation under green and low-carbon transition and provides practical enlightenment for enterprises to achieve sustainable development. This paper constructs a comprehensive index system of CSR from five dimensions (innovation, coordination, sustainability, openness, and sharing), and CSR reputation of China’s A-share listed companies is comprehensively estimated by using an entropy method and data from 2013 to 2021. Then, from the perspective of external supervision and internal governance, we discuss the influence factors of CSR reputation, with an emphasis on the impact of public environmental concerns. Finally, the realization mechanism of CSR is further revealed. It is found that public environmental concern and the expansion of the enterprise scale boost the enhancement of CSR reputation. However, a higher proportion of female managers tends to hinder CSR reputation. Furthermore, public environmental concern plays a more prominent role in improving CSR reputation of non-state-owned and eastern enterprises. Additionally, public environmental concern significantly enhances CSR reputation through green technology innovation and executive environmental awareness. This research provides valuable insights for improving CSR reputation and optimizing regulatory compliance and governance practices. Full article
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15 pages, 512 KiB  
Article
Recognizable Languages of k-Forcing Automata
by Marzieh Shamsizadeh, Mohammad Mehdi Zahedi, Khadijeh Abolpour and Manuel De la Sen
Math. Comput. Appl. 2024, 29(3), 32; https://doi.org/10.3390/mca29030032 (registering DOI) - 25 Apr 2024
Abstract
In this study, we show that automata theory is also a suitable tool for analyzing a more complex type of the k-forcing process. First, the definition of k-forcing automata is presented according to the definition of k-forcing for graphs. Moreover, we study and [...] Read more.
In this study, we show that automata theory is also a suitable tool for analyzing a more complex type of the k-forcing process. First, the definition of k-forcing automata is presented according to the definition of k-forcing for graphs. Moreover, we study and discuss the language of k-forcing automata for particular graphs. Also, for some graphs with different k-forcing sets, we study the languages of their k-forcing automata. In addition, for some given recognizable languages, we study the structure of graphs. After that, we show that k-forcing automata arising from isomorph graphs are also isomorph. Also, we present the style of words that can be recognized with k-forcing automata. Moreover, we introduce the structure of graphs the k-forcing automata arising from which recognize some particular languages. To clarify the notions and the results obtained in this study, some examples are submitted as well. Full article
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14 pages, 2990 KiB  
Article
Charge Storage Properties of Ferrimagnetic BaFe12O19 and Polypyrrole–BaFe12O19 Composites
by Silin Chen and Igor Zhitomirsky
Molecules 2024, 29(9), 1979; https://doi.org/10.3390/molecules29091979 (registering DOI) - 25 Apr 2024
Abstract
This investigation is motivated by an interest in multiferroic BaFe12O19 (BFO), which combines advanced ferrimagnetic and ferroelectric properties at room temperature and exhibits interesting magnetoelectric phenomena. The ferroelectric charge storage properties of BFO are limited due to high coercivity, low [...] Read more.
This investigation is motivated by an interest in multiferroic BaFe12O19 (BFO), which combines advanced ferrimagnetic and ferroelectric properties at room temperature and exhibits interesting magnetoelectric phenomena. The ferroelectric charge storage properties of BFO are limited due to high coercivity, low dielectric constant, and high dielectric losses. We report the pseudocapacitive behavior of BFO, which allows superior charge storage compared to the ferroelectric charge storage mechanism. The BFO electrodes show a remarkably high capacitance of 1.34 F cm−2 in a neutral Na2SO4 electrolyte. The charging mechanism is discussed. The capacitive behavior is linked to the beneficial effect of high-energy ball milling (HEBM) and the use of an efficient dispersant, which facilitates charge transfer. Another approach is based on the use of conductive polypyrrole (PPy) for the fabrication of PPy-BFO composites. The choice of new polyaromatic dopants with a high charge-to-mass ratio plays a crucial role in achieving a high capacitance of 4.66 F cm−2 for pure PPy electrodes. The composite PPy-BFO (50/50) electrodes show a capacitance of 3.39 F cm−2, low impedance, reduced charge transfer resistance, enhanced capacitance retention at fast charging rates, and good cyclic stability due to the beneficial effect of advanced dopants, HEBM, and synergy of the contribution of PPy and BFO. Full article
31 pages, 1077 KiB  
Article
How Does Digital Leadership Foster Employee Innovative Behavior: A Cognitive–Affective Processing System Perspective
by Pengbin Gao and Yinghui Gao
Behav. Sci. 2024, 14(5), 362; https://doi.org/10.3390/bs14050362 (registering DOI) - 25 Apr 2024
Abstract
Employee innovative behavior is crucial for organizations to engage in innovative activities and gain competitive advantages in the context of digital transformation. Despite many studies having focused on the relationship between leadership and employee innovative behavior, the role of digital leadership and the [...] Read more.
Employee innovative behavior is crucial for organizations to engage in innovative activities and gain competitive advantages in the context of digital transformation. Despite many studies having focused on the relationship between leadership and employee innovative behavior, the role of digital leadership and the underlying mechanisms for employee innovative behavior remain unclear. Using the cognitive–affective processing system framework, the study investigated the dual mediating role of psychological empowerment and affective commitment between digital leadership and employee innovative behavior and the moderating role of a proactive personality in such relationships. Employing data from 359 employees, the study conducted structure equation modeling to examine the hypotheses. The results show that digital leadership influences employee innovative behavior through psychological empowerment but not affective commitment. Furthermore, a proactive personality does not moderate the direct effect of digital leadership on psychological empowerment and affective commitment or the indirect effect of digital leadership on employee innovative behavior. Theoretical and practical implications are discussed. Full article
(This article belongs to the Section Organizational Behaviors)
22 pages, 11461 KiB  
Article
Comprehensive Stable Control Strategy for a Typical Underactuated Manipulator Considering Several Uncertainties
by Zixin Huang, Wei Wang, Ba Zeng, Chengsong Yu and Yaosheng Zhou
Appl. Sci. 2024, 14(9), 3663; https://doi.org/10.3390/app14093663 (registering DOI) - 25 Apr 2024
Abstract
This article proposes a comprehensive stable control strategy for the planar multi-link underactuated manipulator (PMLUM), considering several uncertainties. According to the nilpotent approximation property, the control procedure is split into two stages. In the first stage of control, we postulate the idea of [...] Read more.
This article proposes a comprehensive stable control strategy for the planar multi-link underactuated manipulator (PMLUM), considering several uncertainties. According to the nilpotent approximation property, the control procedure is split into two stages. In the first stage of control, we postulate the idea of model degradation, reducing the PMLUM to a planar virtual Pendubot (PVP). This occurs by controlling the active link (AL) to a specific desired position and the passive link (PL) moves along with it. When the AL moves to the desired position, the second phase of control is entered. Meanwhile, all ALs are regarded as a whole, so the PMLUM can be regarded as a mechanical arm with 2-DOF. In the second stage of control, due to the nilpotent approximation feature of the PVP, the PVP is guided to the desired angle using the iterative steering technique. Simulation experiments are carried out on active–active–passive (AAP) and active–active–active–passive (AAAP) systems under major uncertainties, which contain initial velocity and torque disturbances. The final results validate the effectiveness of the method proposed. Full article
(This article belongs to the Section Robotics and Automation)
14 pages, 754 KiB  
Review
Reflections on the Origin of Coded Protein Biosynthesis
by Juan Carlos Fontecilla-Camps
Biomolecules 2024, 14(5), 518; https://doi.org/10.3390/biom14050518 (registering DOI) - 25 Apr 2024
Abstract
The principle of continuity posits that some central features of primordial biocatalytic mechanisms should still be present in the genetically dependent pathway of protein synthesis, a crucial step in the emergence of life. Key bimolecular reactions of this process are catalyzed by DNA-dependent [...] Read more.
The principle of continuity posits that some central features of primordial biocatalytic mechanisms should still be present in the genetically dependent pathway of protein synthesis, a crucial step in the emergence of life. Key bimolecular reactions of this process are catalyzed by DNA-dependent RNA polymerases, aminoacyl-tRNA synthetases, and ribosomes. Remarkably, none of these biocatalysts contribute chemically active groups to their respective reactions. Instead, structural and functional studies have demonstrated that nucleotidic α-phosphate and β-d-ribosyl 2′ OH and 3′ OH groups can help their own catalysis, a process which, consequently, has been called “substrate-assisted”. Furthermore, upon binding, the substrates significantly lower the entropy of activation, exclude water from these catalysts’ active sites, and are readily positioned for a reaction. This binding mode has been described as an “entropy trap”. The combination of this effect with substrate-assisted catalysis results in reactions that are stereochemically and mechanistically simpler than the ones found in most modern enzymes. This observation is consistent with the way in which primordial catalysts could have operated; it may also explain why, thanks to their complementary reactivities, β-d-ribose and phosphate were naturally selected to be the central components of early coding polymers. Full article
(This article belongs to the Section Enzymology)
11 pages, 395 KiB  
Article
Assessing Uveitis Risk following Pediatric Down Syndrome Diagnosis: A TriNetX Database Study
by Alan Y. Hsu, Yu-Hsun Wang, Chun-Ju Lin, You-Ling Li, Ning-Yi Hsia, Chun-Ting Lai, Hou-Ting Kuo, Huan-Sheng Chen, Yi-Yu Tsai and James Cheng-Chung Wei
Medicina 2024, 60(5), 710; https://doi.org/10.3390/medicina60050710 (registering DOI) - 25 Apr 2024
Abstract
Background and Objectives: The risks of uveitis development among pediatric patients with Down syndrome (DS) remain unclear. Therefore, we aimed to determine the risk of uveitis following a diagnosis of DS. Materials and Methods: This multi-institutional retrospective cohort study utilized the TriNetX database [...] Read more.
Background and Objectives: The risks of uveitis development among pediatric patients with Down syndrome (DS) remain unclear. Therefore, we aimed to determine the risk of uveitis following a diagnosis of DS. Materials and Methods: This multi-institutional retrospective cohort study utilized the TriNetX database to identify individuals aged 18 years and younger with and without a diagnosis of DS between 1 January 2000 and 31 December 2023. The non-DS cohort consisted of randomly selected control patients matched by selected variables. This included gender, age, ethnicity, and certain comorbidities. The main outcome is the incidence of new-onset uveitis. Statistical analysis of the uveitis risk was reported using hazard ratios (HRs) and 95% confidence intervals (CIs). Separate analyses of the uveitis risk among DS patients based on age groups and gender were also performed. Results: A total of 53,993 individuals with DS (46.83% female, 58.26% white, mean age at index 5.21 ± 5.76 years) and 53,993 non-DS individuals (45.56% female, 58.28% white, mean age at index 5.21 ± 5.76 years) were recruited from the TriNetX database. Our analysis also showed no overall increased risk of uveitis among DS patients (HR: 1.33 [CI: 0.89–1.99]) compared to the non-DS cohort across the 23-year study period. Subgroup analyses based on different age groups showed that those aged 0–1 year (HR: 1.36 [CI: 0.68–2.72]), 0–5 years (HR: 1.34 [CI: 0.75–2.39]), and 6–18 years (HR: 1.15 [CI: 0.67–1.96]) were found to have no association with uveitis risk compared to their respective non-DS comparators. There was also no increased risk of uveitis among females (HR: 1.49 [CI: 0.87–2.56]) or males (HR: 0.82 [CI: 0.48–1.41]) with DS compared to their respective non-DS comparators. Conclusions: Our study found no overall increased risk of uveitis following a diagnosis of DS compared to a matched control population. Full article
17 pages, 333 KiB  
Article
The Linkage between Corporate Research and Development Intensity and Stock Returns: Empirical Evidence
by Sameena Ghazal, Tariq Aziz, Mosab I. Tabash and Krzysztof Drachal
J. Risk Financial Manag. 2024, 17(5), 180; https://doi.org/10.3390/jrfm17050180 (registering DOI) - 25 Apr 2024
Abstract
Research and development (R&D) is a significant driver of innovation that leads to superior performance. The present study attempts to examine the relationship between R&D intensity and a firm’s performance at both aggregate and industry levels in the emerging market of India using [...] Read more.
Research and development (R&D) is a significant driver of innovation that leads to superior performance. The present study attempts to examine the relationship between R&D intensity and a firm’s performance at both aggregate and industry levels in the emerging market of India using a battery of R&D intensity measures and stock market returns as a measure of a firm’s performance. The study was conducted on 1097 companies from six R&D-intensive industries. The Fama-French portfolio formation method was used to evaluate the stock market performance of R&D-intensive firms for both equal-weighted (EW) and value-weighted (VW) returns. The findings suggest that R&D intensity and stock returns show a positive relationship. A long–short strategy in R&D-intense firms has yielded 1.43% (t = 4.22) per month in the sample. In general, the results suggest an undervaluation of highly R&D-intensive firms that investors can exploit for above-average returns. The effect is not homogeneous across return schemes (equal-weighted and value-weighted) or across industries. R&D growth measures and R&D capital are not found to have significant impacts on stock returns. Both the market firm size and age are included as control variables, and the results reveal that the relationship is robust to these control variables. The sub-periods ranging from 2000 to 2007 and 2008 to 2019 have been considered in the present study and the results are consistent with the overall sample. The study fills the existing empirical void for R&D intensity and stock returns in relation to the emerging market of India. Full article
(This article belongs to the Section Financial Markets)
17 pages, 4682 KiB  
Article
Purified Pyropia yezoensis Pigment Extract-Based Tandem Dye Synthesis
by Hojun Lee, Taejun Han and Jihae Park
Mar. Drugs 2024, 22(5), 197; https://doi.org/10.3390/md22050197 (registering DOI) - 25 Apr 2024
Abstract
Red phycoerythrin (R-PE) is a highly valuable protein found in an edible seaweed, Pyropia yezoensis. It is used extensively in biotechnological applications due to its strong fluorescence and stability in diverse environments. However, the current methods for extracting and purifying R-PE are [...] Read more.
Red phycoerythrin (R-PE) is a highly valuable protein found in an edible seaweed, Pyropia yezoensis. It is used extensively in biotechnological applications due to its strong fluorescence and stability in diverse environments. However, the current methods for extracting and purifying R-PE are costly and unsustainable. The aim of the present study was to enhance the financial viability of the process by improving the extraction and purification of R-PE from dried P. yezoensis and to further enhance R-PE value by incorporating it into a tandem dye for molecular biology applications. A combination of ultrafiltration, ion exchange chromatography, and gel filtration yielded concentrated (1 mg·mL–1) R-PE at 99% purity. Using purified PE and Cyanine5 (Cy5), an organic tandem dye, phycoerythrin-Cy5 (PE-Cy5), was subsequently established. In comparison to a commercially available tandem dye, PE-Cy5 exhibited 202.3% stronger fluorescence, rendering it suitable for imaging and analyzes that require high sensitivity, enhanced signal-to-noise ratio, broad dynamic range, or shorter exposure times to minimize potential damage to samples. The techno-economic analysis confirmed the financial feasibility of the innovative technique for the extraction and purification of R-PE and PE-Cy5 production. Full article
(This article belongs to the Section Marine Biotechnology Related to Drug Discovery or Production)
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25 pages, 3177 KiB  
Article
Experimental Research on the Floating Amount of Shield Tunnel Based on the Innovative Cumulative Floating Amount Calculation Method
by Jingrong Wu and Jing Chen
Buildings 2024, 14(5), 1228; https://doi.org/10.3390/buildings14051228 (registering DOI) - 25 Apr 2024
Abstract
The study of shield tunnel segment flotation is crucial for controlling the precision of underground excavation projects. Based on Winkler’s beam foundation theory, the load structure method, and the equivalent continuous beam model, and by considering the mechanical and spatial conditions that cause [...] Read more.
The study of shield tunnel segment flotation is crucial for controlling the precision of underground excavation projects. Based on Winkler’s beam foundation theory, the load structure method, and the equivalent continuous beam model, and by considering the mechanical and spatial conditions that cause segment flotation, a novel theoretical calculation method for cumulative flotation is proposed using a simplified equivalent stiffness model of the tunnel. Additionally, a new concept of “equivalent flotation force” is introduced. The rationality and applicability of this theoretical calculation method are verified by comparing it with on-site construction data from the Yuanjiang River Crossing Tunnel Project in Changde, Hunan Province, China. The experimental results demonstrate that the theoretical calculation closely approximates the surface deformation monitoring data of the tunnel alignment in the eastern section of the project, and their deformation patterns are similar. Near the starting shaft, there is significant settlement influenced by stratum loss due to smaller tunnel flotation, with greater settlement occurring in the upper part. However, at approximately 45 m into both sections, they enter a deformation stability zone showing significant correlation in longitudinal deformation. Through comparison and verification of on-site experiments and theoretical model analysis, we preliminarily elucidate the feasibility of this innovative cumulative flotation theoretical calculation method which provides an important theoretical basis for assessing segment flotation issues in subsequent tunnel shield construction evaluations. Full article
(This article belongs to the Section Building Structures)
32 pages, 5019 KiB  
Article
Trophic Position of the White Worm (Enchytraeus albidus) in the Context of Digestive Enzyme Genes Revealed by Transcriptomics Analysis
by Łukasz Gajda, Agata Daszkowska-Golec and Piotr Świątek
Int. J. Mol. Sci. 2024, 25(9), 4685; https://doi.org/10.3390/ijms25094685 (registering DOI) - 25 Apr 2024
Abstract
To assess the impact of Enchytraeidae (potworms) on the functioning of the decomposer system, knowledge of the feeding preferences of enchytraeid species is required. Different food preferences can be explained by variations in enzymatic activities among different enchytraeid species, as there are no [...] Read more.
To assess the impact of Enchytraeidae (potworms) on the functioning of the decomposer system, knowledge of the feeding preferences of enchytraeid species is required. Different food preferences can be explained by variations in enzymatic activities among different enchytraeid species, as there are no significant differences in the morphology or anatomy of their alimentary tracts. However, it is crucial to distinguish between the contribution of microbial enzymes and the animal’s digestive capacity. Here, we computationally analyzed the endogenous digestive enzyme genes in Enchytraeus albidus. The analysis was based on RNA-Seq of COI-monohaplotype culture (PL-A strain) specimens, utilizing transcriptome profiling to determine the trophic position of the species. We also corroborated the results obtained using transcriptomics data from genetically heterogeneous freeze-tolerant strains. Our results revealed that E. albidus expresses a wide range of glycosidases, including GH9 cellulases and a specific digestive SH3b-domain-containing i-type lysozyme, previously described in the earthworm Eisenia andrei. Therefore, E. albidus combines traits of both primary decomposers (primary saprophytophages) and secondary decomposers (sapro-microphytophages/microbivores) and can be defined as an intermediate decomposer. Based on assemblies of publicly available RNA-Seq reads, we found close homologs for these cellulases and i-type lysozymes in various clitellate taxa, including Crassiclitellata and Enchytraeidae. Full article
(This article belongs to the Special Issue State-of-the-Art Molecular Genetics and Genomics in Poland 2.0)
3 pages, 166 KiB  
Editorial
Editorial: Impact of Special Issue “The Microbial Population of the Gastrointestinal Tract of Animals: Impacts on Host Physiology”
by Jeferson M. Lourenco and Todd R. Callaway
Microorganisms 2024, 12(5), 859; https://doi.org/10.3390/microorganisms12050859 (registering DOI) - 25 Apr 2024
Abstract
In recent years, there has been an exponential increase in the number of papers that have investigated the microbiome of animals and humans [...] Full article
16 pages, 654 KiB  
Article
Views on Gender Differences in the Physics Classroom
by Natascha Musters, Rian Aarts, Marije Van Amelsvoort and Marc Swerts
Educ. Sci. 2024, 14(5), 457; https://doi.org/10.3390/educsci14050457 (registering DOI) - 25 Apr 2024
Abstract
Concerns about the differences between boys and girls in educational achievement, school careers and educational choices have existed since the last century. Despite ongoing research, we still do not have a complete picture of gender-based differences in education. In particular, there is little [...] Read more.
Concerns about the differences between boys and girls in educational achievement, school careers and educational choices have existed since the last century. Despite ongoing research, we still do not have a complete picture of gender-based differences in education. In particular, there is little comparative research on how teachers and students experience and deal with gender differences in their classrooms. Therefore, this study focuses on teacher and student perspectives on gender differences in the physics classroom of Dutch upper secondary education. The data were collected through questionnaires distributed among physics teachers (N = 72) and students (N = 212). The questionnaires for students and teachers were designed to reveal their perceptions of gender differences in the classroom, focusing on student learning characteristics and teacher–student interactions. Gender differences are reported to a larger extent by teachers than by students, especially in the area of students’ learning characteristics (e.g., boys showing more talent and interest in physics, girls showing more effort and self-regulation) and some in teacher–student interactions (e.g., girls asking teachers more questions). We conclude that concerns about differences between boys and girls are still present and need further research. More work is needed to fully understand the implications of these differences, which are expected to have an important impact on classroom interventions and guidelines for teachers to use in their classrooms. Full article
(This article belongs to the Special Issue Gender and STEM Education)
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21 pages, 3759 KiB  
Article
A Modified SVPWM Strategy for Reducing PWM Voltage Noise and Balancing Neutral Point Potential
by Renxi Gong, Hao Wu, Jing Tang and Xingyuan Wan
Electronics 2024, 13(9), 1656; https://doi.org/10.3390/electronics13091656 (registering DOI) - 25 Apr 2024
Abstract
PWM (pulse width modulation) is the most widely applied current conversion technology, but the high-frequency harmonics it causes have a significant negative impact on inverter system performance. This paper focuses on the three-phase T-type three-level inverter as the research object and addresses existing [...] Read more.
PWM (pulse width modulation) is the most widely applied current conversion technology, but the high-frequency harmonics it causes have a significant negative impact on inverter system performance. This paper focuses on the three-phase T-type three-level inverter as the research object and addresses existing PWM voltage noise and midpoint potential imbalance issues by proposing an improved random SVPWM strategy, named Neutral Point Potential Balance Random Space Vector PWM (NPB−RSVPWM). The NPB−RSVPWM strategy includes three main steps: (1) introducing a midpoint potential balancing control loop to adjust the synthesis timing of the effective vectors to generate pulse signals, optimizing midpoint potential balance; (2) employing a randomly varying carrier frequency in place of the carrier used in the SVPWM strategy to generate the driving signals for switching devices; and (3) controlling the inverter through the driving pulse signals. This strategy optimizes the synthesis sequence of traditional SVPWM strategy vectors and incorporates random frequency modulation techniques. The mathematical model analyzes PWM harmonic expressions corresponding to fixed switching frequencies, and a random frequency carrier is chosen to suppress these PWM harmonics. The effective vector’s equivalent circuit is analyzed, proposing a technique for optimized vector synthesis timing. The simulation and experimental results verify that the NPB−RSVPWM technique can disperse PWM harmonic energy, reduce voltage noise, and optimize midpoint potential balance. Under the NPB−RSVPWM strategy, the line voltage spectrum becomes uniform, the maximum harmonic content is greatly reduced, and the fluctuation in the DC side midpoint potential is significantly improved. Compared with the traditional SVPWM strategy and random PWM strategy, the NPB−RSVPWM strategy has a lower voltage noise, smaller total harmonic distortion, and a more stable midpoint potential. The effectiveness and feasibility of the NPB−RSVPWM strategy are verified by simulation and experimental results. Full article
17 pages, 1039 KiB  
Review
The Causes and Consequences of DNA Damage and Chromosomal Instability Induced by Human Papillomavirus
by Kathryn M. Jones, Ava Bryan, Emily McCunn, Pate E. Lantz, Hunter Blalock, Isabel C. Ojeda, Kavi Mehta and Pippa F. Cosper
Cancers 2024, 16(9), 1662; https://doi.org/10.3390/cancers16091662 (registering DOI) - 25 Apr 2024
Abstract
High-risk human papillomaviruses (HPVs) are the main cause of cervical, oropharyngeal, and anogenital cancers, which are all treated with definitive chemoradiation therapy when locally advanced. HPV proteins are known to exploit the host DNA damage response to enable viral replication and the epithelial [...] Read more.
High-risk human papillomaviruses (HPVs) are the main cause of cervical, oropharyngeal, and anogenital cancers, which are all treated with definitive chemoradiation therapy when locally advanced. HPV proteins are known to exploit the host DNA damage response to enable viral replication and the epithelial differentiation protocol. This has far-reaching consequences for the host genome, as the DNA damage response is critical for the maintenance of genomic stability. HPV+ cells therefore have increased DNA damage, leading to widespread genomic instability, a hallmark of cancer, which can contribute to tumorigenesis. Following transformation, high-risk HPV oncoproteins induce chromosomal instability, or chromosome missegregation during mitosis, which is associated with a further increase in DNA damage, particularly due to micronuclei and double-strand break formation. Thus, HPV induces significant DNA damage and activation of the DNA damage response in multiple contexts, which likely affects radiation sensitivity and efficacy. Here, we review how HPV activates the DNA damage response, how it induces chromosome missegregation and micronuclei formation, and discuss how these factors may affect radiation response. Understanding how HPV affects the DNA damage response in the context of radiation therapy may help determine potential mechanisms to improve therapeutic response. Full article
10 pages, 410 KiB  
Article
Cosmological Test of an Ultraviolet Origin of Dark Energy
by Hans Christiansen, Bence Takács and Steen H. Hansen
Universe 2024, 10(5), 193; https://doi.org/10.3390/universe10050193 (registering DOI) - 25 Apr 2024
Abstract
The accelerated expansion of the Universe is impressively well described by a cosmological constant. However, the observed value of the cosmological constant is much smaller than expected based on quantum field theories. Recent efforts to achieve consistency in these theories have proposed a [...] Read more.
The accelerated expansion of the Universe is impressively well described by a cosmological constant. However, the observed value of the cosmological constant is much smaller than expected based on quantum field theories. Recent efforts to achieve consistency in these theories have proposed a relationship between Dark Energy and the most compact objects, such as black holes (BHs). However, experimental tests are very challenging to devise and perform. In this article, we present a testable model with no cosmological constant in which the accelerated expansion can be driven by black holes. The model couples the expansion of the Universe (the Friedmann equation) with the mass function of cosmological halos (using the Press–Schechter formalism). Through the observed link between halo masses and BH masses, one thus gets a coupling between the expansion rate of the Universe and the BHs. We compare the predictions of this simple BH model with SN1a data and find poor agreement with observations. Our method is sufficiently general to allow us to also test a fundamentally different model, also without a cosmological constant, where the accelerated expansion is driven by a new force proportional to the internal velocity dispersion of galaxies. Surprisingly enough, this model cannot be excluded using the SN1a data. Full article
(This article belongs to the Special Issue The Nature of Dark Energy)
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11 pages, 620 KiB  
Review
Therapeutic Applications of Aggregatibacter actinomycetemcomitans Leukotoxin
by Scott C. Kachlany and Brian A. Vega
Pathogens 2024, 13(5), 354; https://doi.org/10.3390/pathogens13050354 (registering DOI) - 25 Apr 2024
Abstract
Aggregatibacter actinomycetemcomitans is a Gram-negative oral bacterium that has been primarily studied for its role in causing periodontal disease. The bacterium has also been implicated in several systemic diseases such as endocarditis and soft tissue abscesses. Leukotoxin (LtxA) is perhaps the best studied [...] Read more.
Aggregatibacter actinomycetemcomitans is a Gram-negative oral bacterium that has been primarily studied for its role in causing periodontal disease. The bacterium has also been implicated in several systemic diseases such as endocarditis and soft tissue abscesses. Leukotoxin (LtxA) is perhaps the best studied protein virulence factor from A. actinomycetemcomitans. The protein can rapidly destroy white blood cells (WBCs), helping the bacterium to subvert the host immune system. The functional receptor for LtxA is lymphocyte function associated antigen-1 (LFA-1), which is expressed exclusively on the surfaces of WBCs. Bacterial expression and secretion of the protein are highly regulated and controlled by a number of genetic and environmental factors. The mechanism of LtxA action on WBCs varies depending on the type of cell that is being killed, and the protein has been shown to activate numerous cell death pathways in susceptible cells. In addition to serving as an important virulence factor for the bacterium, because of its exquisite specificity and rapid activity, LtxA is also being investigated as a therapeutic agent that may be used to treat diseases such as hematological malignancies and autoimmune/inflammatory diseases. It is our hope that this review will inspire an increased intensity of research related to LtxA and its effect on Aggressive Periodontitis, the disease that led to its initial discovery. Full article
(This article belongs to the Special Issue Aggregatibacter actinomycetemcomitans)
16 pages, 674 KiB  
Review
Epigenetic and Coping Mechanisms of Stress in Affective Disorders: A Scoping Review
by Brenda-Cristiana Bernad, Mirela-Cleopatra Tomescu, Teodora Anghel, Diana Lungeanu, Virgil Enătescu, Elena Silvia Bernad, Vlad Nicoraș, Diana-Aurora Arnautu and Lavinia Hogea
Medicina 2024, 60(5), 709; https://doi.org/10.3390/medicina60050709 (registering DOI) - 25 Apr 2024
Abstract
This review aims to explore the intricate relationship among epigenetic mechanisms, stress, and affective disorders, focusing on how early life experiences and coping mechanisms contribute to susceptibility to mood disorders. Epigenetic factors play a crucial role in regulating gene expression without altering the [...] Read more.
This review aims to explore the intricate relationship among epigenetic mechanisms, stress, and affective disorders, focusing on how early life experiences and coping mechanisms contribute to susceptibility to mood disorders. Epigenetic factors play a crucial role in regulating gene expression without altering the DNA (deoxyribonucleic acid) sequence, and recent research has revealed associations between epigenetic changes and maladaptive responses to stress or psychiatric disorders. A scoping review of 33 studies employing the PRISMA-S (Preferred Reporting Items for Systematic Reviews and Meta-Analyses—Statement) guidelines investigates the role of stress-induced epigenetic mechanisms and coping strategies in affective disorder occurrence, development, and progression. The analysis encompasses various stress factors, including childhood trauma, work-related stress, and dietary deficiencies, alongside epigenetic changes, such as DNA methylation and altered gene expression. Findings indicate that specific stress-related genes frequently exhibit epigenetic changes associated with affective disorders. Moreover, the review examines coping mechanisms in patients with bipolar disorder and major depressive disorder, revealing mixed associations between coping strategies and symptom severity. While active coping is correlated with better outcomes, emotion-focused coping may exacerbate depressive or manic episodes. Overall, this review underscores the complex interplay among genetic predisposition, environmental stressors, coping mechanisms, and affective disorders. Understanding these interactions is essential for developing targeted interventions and personalized treatment strategies for individuals with mood disorders. However, further research is needed to elucidate specific genomic loci involved in affective disorders and the clinical implications of coping strategies in therapeutic settings. Full article
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16 pages, 844 KiB  
Review
A Comprehensive Review and Tutorial on Confounding Adjustment Methods for Estimating Treatment Effects Using Observational Data
by Amy X. Shi, Paul N. Zivich and Haitao Chu
Appl. Sci. 2024, 14(9), 3662; https://doi.org/10.3390/app14093662 (registering DOI) - 25 Apr 2024
Abstract
Controlling for confounding bias is crucial in causal inference. Causal inference using data from observational studies (e.g., electronic health records) or imperfectly randomized trials (e.g., imperfect randomization or compliance) requires accounting for confounding variables. Many different methods are currently employed to mitigate bias [...] Read more.
Controlling for confounding bias is crucial in causal inference. Causal inference using data from observational studies (e.g., electronic health records) or imperfectly randomized trials (e.g., imperfect randomization or compliance) requires accounting for confounding variables. Many different methods are currently employed to mitigate bias due to confounding. This paper provides a comprehensive review and tutorial of common estimands and confounding adjustment approaches, including outcome regression, g-computation, propensity score, and doubly robust methods. We discuss bias and precision, advantages and disadvantages, and software implementation for each method. Moreover, approaches are illustrated empirically with a reproducible case study. We conclude that different scientific questions are better addressed by certain estimands. No estimand is uniformly more appropriate. Upon selecting an estimand, decisions on which estimator can be driven by performance and available background knowledge. Full article
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18 pages, 3985 KiB  
Article
Study on Properties of Micro-Nano Magnetic Composite Prepared by Mechanochemical Method of NdFeB Secondary Waste and Removal of As (V) from Mine Water
by Xiujuan Feng and Yicheng Rao
Water 2024, 16(9), 1234; https://doi.org/10.3390/w16091234 (registering DOI) - 25 Apr 2024
Abstract
The secondary waste produced by NdFeB waste after rare earth recycling, with an annual output of more than tens of thousands of tons, is the largest solid waste emission source in the rare earth industry, and long-term storage causes land resource occupation and [...] Read more.
The secondary waste produced by NdFeB waste after rare earth recycling, with an annual output of more than tens of thousands of tons, is the largest solid waste emission source in the rare earth industry, and long-term storage causes land resource occupation and environmental pollution. Arsenic-containing mine wastewater has serious harm, wide distribution, and long duration of pollution. In this study, the mechanical ball milling method was used to activate NdFeB secondary waste to prepare micro-nano magnetic composite materials, the main components of which are Fe2O3, Fe3O4, and C. Under mechanical mechanochemical action, the particles are more dispersed, the particle size decreases, the specific surface area increases significantly, the crystal structure changes to amorphous structure, the degree of amorphous shape increases, and the content of Fe-OH increases. Applied to the treatment of As (V) in simulated mine water, it was found that the removal of As (V) by this material was mainly based on chemisorption and monolayer adsorption, and the maximum adsorption amount reached 10.477 mg/g. Zeta, FT-IT, and XPS characterization confirmed that the removal of As (V) was a coordination exchange reaction between the material and As (V) to form an inner sphere complex. The removal rate of As (V) decreased from 94.33% to 73.56% when the initial concentration of solution was 10 mg/L, pH value was 3.0, and material dosage was 1 g/L after 5 times of regrowth. This study provides a new way for the application of NdFeB secondary waste, which has low cost, green environmental protection, and wide application prospects. Full article
(This article belongs to the Special Issue Water, Wastewater and Waste Management for Sustainable Development)

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