Saved Queries

by Vladimir Guterman, Anastasia Alekseenko, Sergey Belenov, Vladislav Menshikov, Elizaveta Moguchikh, Irina Novomlinskaya, Kirill Paperzh and Ilya Pankov

Nanomaterials 2024, 14(20), 1672; https://doi.org/10.3390/nano14201672 (registering DOI) - 18 Oct 2024

Abstract

Bimetallic platinum-containing catalysts are deemed promising for electrolyzers and proton-exchange membrane fuel cells (PEMFCs). A significant number of laboratory studies and commercial offers are related to PtNi/C and PtCo/C electrocatalysts. The behavior of PtPd/C catalysts has been studied much less, although palladium itself is the metal closest to platinum in its properties. Using a series of characterization methods, this paper presents a comparative study of structural characteristics of the commercial PtPd/C catalysts containing 38% wt. of precious metals and the well-known HiSpec4000 Pt/C catalyst. The electrochemical behavior of the catalysts was studied both in a three-electrode electrochemical cell and in the membrane electrode assemblies (MEAs) of hydrogen–air PEMFCs. Both PtPd/C samples demonstrated higher values of the electrochemically active surface area, as well as greater specific and mass activity in the oxygen reduction reaction in comparison with conventional Pt/C, while not being inferior to the latter in durability. The MEA based on the best of the PtPd/C catalysts also exhibited higher performance in single tests and long-term durability testing. The results of this study conducted indicate the prospects of using bimetallic PtPd/C materials for cathode catalysts in PEMFCs. Full article

(This article belongs to the Section Energy and Catalysis)

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18 pages, 4401 KiB

Open AccessArticle

Performance Optimization of Alkaline Multi-Industrial Waste-Based Cementitious Materials for Soil Solidification

by Xiaoli Wang, Xiancong Wang, Pingfeng Fu, Jinjin Shi and Miao Xu

Materials 2024, 17(20), 5077; https://doi.org/10.3390/ma17205077 (registering DOI) - 18 Oct 2024

Abstract

This study presents the development of eco-friendly cementitious materials for soil stabilization, based on alkaline multi-industrial waste (AMIW), using steel slag (SS), blast furnace slag (BFS), carbide slag (CS), fly ash (FA) and flue gas desulfurization gypsum (FGDG) as the raw materials. The optimal AMIW-based cementitious material composition determined through orthogonal experiments was SS:CS:FGDG:BFS:FA = 15:10:15:44:16. Central composite design (CCD) in response surface methodology (RSM) was employed to optimize the curing process parameters. The maximum 7-day unconfined compressive strength (7d UCS) was achieved under the optimal conditions of 18.51% moisture content, 11.46% curing agent content and 26.48 min of mix-grinding time. The 7d UCS of the AMIW-stabilized soil showed a 24% improvement over ordinary Portland cement (OPC)-stabilized soil. Rietveld refinement results demonstrated that the main hydration products of the stabilized soil were C-S-H and ettringite. After curing for 7 days to 28 days, the C-S-H content increased from 3.31% to 5.76%, while the ettringite content increased from 1.41% to 3.54%. Mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) analysis revealed that with the extension of curing time, the pores of the stabilized soil become smaller and the structure becomes denser, resulting in an improvement in compressive strength. Full article

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24 pages, 1279 KiB

Open AccessArticle

Evaluation of a Model of Transitional Care After Preterm Birth on Parents’ Mental Health and Self-Efficacy: A Randomized Controlled Pilot Trial

by Natascha Schuetz Haemmerli, Liliane Stoffel, Kai-Uwe Schmitt, Tilman Humpl, Mathias Nelle, Odile Stalder and Eva Cignacco

Children 2024, 11(10), 1260; https://doi.org/10.3390/children11101260 (registering DOI) - 18 Oct 2024

Abstract

Background/Objectives: Parents of premature infants experience depression, anxiety, post-traumatic stress disorder, and increased stress, which can negatively impact parent–infant relationships and infant development. To reduce negative consequences and optimally support families, we developed the Transition to Home model (TtH). In this randomized controlled pilot trial (RCT), the feasibility of performing an experimental study to analyse the effects of TtH on parental mental health over time was evaluated. Methods: The following domains were assessed: recruitment, follow-up and study burden, outcome measures used and parental mental health outcomes. We included n = 22 parent couples with their preterm infants in the control group and n = 23 in the intervention group. Depression, anxiety and post-traumatic stress disorders, parenting stress, and parental self-efficacy were assessed at five timepoints. The study burden was evaluated once at the end of the study. Results: The control and intervention groups had similar socio-demographic characteristics. The groups showed no differences in the mental health outcomes except for depression in mothers at T2 (p = 0.042) and T5 (p = 0.027) and state anxiety in fathers at T2 (p = 0.016). Conclusions: This pilot RCT established a framework for the evaluation of the TtH model of care and demonstrated the viability of the evaluation scheme. The results confirm the suitability of the RCT’s structure and the feasibility of the methods and instruments used. Minor adjustments are recommended to include a more diverse sample in future studies. Full article

(This article belongs to the Section Pediatric Neonatology)

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CONSORT Flow diagram [<a href="#B28-children-11-01260" class="html-bibr">28</a>]. * transferred to another hospital during the recruiting process (n = 97, 27%), discharge during the recruiting process (n = 3, 1%), recruiting stop (n = 20, 6%), completeness of gestational group (n = 15, 4%), parental non-decision (n = 4, 1%), mother or children very sick (n = 7, 2%), parental non-compliance (n = 1, 0.3%). ** includes family transferred to another hospital after T1. Full article ">Figure 2
Course of depression (CES-D) scores from birth until six months after preterm infants’ discharge in mothers and fathers of the CG and the IG. Full article ">

13 pages, 2723 KiB

Open AccessArticle

Research on Wi-Fi Fingerprint Database Construction Method Based on Environmental Feature Awareness

by Jiaxuan Wu, Tianzhong Yang and Zengting Zhang

Appl. Syst. Innov. 2024, 7(5), 99; https://doi.org/10.3390/asi7050099 (registering DOI) - 18 Oct 2024

Abstract

Indoor localization technology is becoming increasingly widespread, but traditional methods for constructing Wi-Fi fingerprint databases face significant challenges, particularly in large, multi-room environments. These methods often suffer from low efficiency and high costs associated with manual data collection. To address these issues, various approaches like crowdsourcing and sparse collection have been introduced, but they still struggle with limitations such as inadequate data accuracy and uneven distribution. In this paper, we present a novel method for constructing Wi-Fi fingerprint databases based on environmental feature awareness. By leveraging deep learning to analyze the relationship between environmental features and Wi-Fi signal strength, our method enables faster and more efficient database construction. Experimental results demonstrate that our environmental feature-aware model significantly outperforms existing methods in prediction accuracy, greatly enhancing both the efficiency and accuracy of Wi-Fi fingerprint database construction. This approach also reduces the need for manual intervention and improves generalization capabilities. Our method proves to be highly practical and adaptable, especially in large-scale structures like nursing homes. It holds a substantial potential for broader application in extensive indoor environments, offering considerable value for widespread adoption. Full article

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General view of the environmental feature perception model. Full article ">Figure 2
Schematic diagram of Wi−Fi fingerprint segmentation. Full article ">Figure 3
Structure of fully connected neural network. Full article ">Figure 4
Structural layout of target objects. Full article ">Figure 5
Comparison of actual and predicted values. Full article ">Figure 6
Loss curve diagram. Full article ">Figure 7
Comparison of deep learning models. Full article ">

11 pages, 6959 KiB

Open AccessCommunication

Metasurface Source Antenna Gain Improvement Using Simple Side Metal Structure

by HongGuk Bae, JaeGon Lee and SangWook Park

Sensors 2024, 24(20), 6695; https://doi.org/10.3390/s24206695 (registering DOI) - 18 Oct 2024

Abstract

As metasurfaces are in the spotlight, research is being conducted to incorporate them into transmitarray (TA) antennas. Among these, as an attempt to create a low-profile design, a patch antenna classified as low-gain can be utilized as an appropriate source antenna. However, for high efficiency of the TA, the gain of the source antenna must be fundamentally improved. For this, a simple side metal structure was applied to a metallic cross-type slot transmitarray. This acts as a resonant element and reflector by utilizing the electromagnetic wave radiated from the source antenna. The changes in the center frequency and gain due to the application of the side metal structure to the source antenna were analyzed. The gain of the source antenna was improved by a total of 4.63 dB. This is expected to be applied to create various source waves and to conduct future research on improving the gain in transmitarray antennas. Full article

(This article belongs to the Collection Advances in Metamaterials or Plasmonics-Based Sensors)

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11 pages, 262 KiB

Open AccessArticle

On Properties of Karamata Slowly Varying Functions with Remainder and Their Applications

by Azam A. Imomov, Erkin E. Tukhtaev and János Sztrik

Mathematics 2024, 12(20), 3266; https://doi.org/10.3390/math12203266 (registering DOI) - 18 Oct 2024

Abstract

In this paper, we study the asymptotic properties of slowly varying functions of one real variable in the sense of Karamata. We establish analogs of fundamental theorems on uniform convergence and integral representation for slowly varying functions with a remainder depending on the types of remainder. We also prove several important theorems on the asymptotic representation of integrals of Karamata functions. Under certain conditions, we observe a “narrowing” of classes of slowly varying functions concerning the types of remainder. At the end of the paper, we discuss the possibilities of the application of slowly varying functions in the theory of stochastic branching systems. In particular, under the condition of the finiteness of the moment of the type

E [x ln x]

for the particle transformation intensity, it is established that the property of slow variation with a remainder is implicitly present in the asymptotic structure of a non-critical Markov branching random system. Full article

(This article belongs to the Special Issue Extreme Values, Regular Variation and Empirical Processes)

19 pages, 2417 KiB

Open AccessArticle

Modification of 316L Stainless Steel, Nickel Titanium, and Cobalt Chromium Surfaces by Irreversible Immobilization of Fibronectin: Towards Improving the Coronary Stent Biocompatibility

by Hesam Dadafarin, Evgeny Konkov, Hojatollah Vali, Irshad Ali and Sasha Omanovic

Molecules 2024, 29(20), 4927; https://doi.org/10.3390/molecules29204927 (registering DOI) - 18 Oct 2024

Abstract

An extracellular matrix protein, fibronectin (Fn), was covalently immobilized on 316L stainless steel, L605 cobalt chromium (CoCr), and nickel titanium (NiTi) surfaces through an 11-mercaptoundecanoic acid (MUA) self-assembled monolayer (SAM) pre-formed on these surfaces. Polarization modulation infrared reflection adsorption spectroscopy (PM-IRRAS) confirmed the presence of Fn on the surfaces. The Fn monolayer attached to the SAM was found to be stable under fluid shear stress. Deconvolution of the Fn amide I band indicated that the secondary structure of Fn changes significantly upon immobilization to the SAM-functionalized metal substrate. Scanning electron microscopy and energy dispersive X-ray analysis revealed that the spacing between Fn molecules on a modified commercial stent surface is approximately 66 nm, which has been reported to be the most appropriate spacing for cell/surface interactions. Full article

(This article belongs to the Special Issue Biomimetic and Functional Materials for Biomedical and Dental Applications)

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15 pages, 15159 KiB

Open AccessArticle

Apoptosis, Mitochondrial Autophagy, Fission, and Fusion Maintain Mitochondrial Homeostasis in Mouse Liver Under Tail Suspension Conditions

by Lu-Fan Li, Jiao Yu, Rui Li, Shan-Shan Li, Jun-Yao Huang, Ming-Di Wang, Li-Na Jiang, Jin-Hui Xu and Zhe Wang

Int. J. Mol. Sci. 2024, 25(20), 11196; https://doi.org/10.3390/ijms252011196 (registering DOI) - 18 Oct 2024

Abstract

Microgravity can induce alterations in liver morphology, structure, and function, with mitochondria playing an important role in these changes. Tail suspension (TS) is a well-established model for simulating the effects of microgravity on muscles and bones, but its impact on liver function remains unclear. In the current study, we explored the regulatory mechanisms of apoptosis, autophagy, fission, and fusion in maintaining liver mitochondrial homeostasis in mice subjected to TS for 2 or 4 weeks (TS2 and TS4). The results showed the following: (1) No significant differences were observed in nuclear ultrastructure or DNA fragmentation between the control and TS-treated groups. (2) No significant differences were detected in the mitochondrial area ratio among the three groups. (3) Cysteine aspartic acid-specific protease 3 (Caspase3) activity and the Bcl-2-associated X protein (bax)/B-cell lymphoma-2 (bcl2) ratio were not higher in the TS2 and TS4 groups compared to the control group. (4) dynamin-related protein 1 (DRP1) protein expression was increased, while mitochondrial fission factor (MFF) protein levels were decreased in the TS2 and TS4 groups compared to the control, suggesting stable mitochondrial fission. (5) No significant differences were observed in the optic atrophy 1 (OPA1), mitofusin 1 and 2 (MFN1 and MFN2) protein expression levels across the three groups. (6) Mitochondrial autophagy vesicles were present in the TS2 and TS4 groups, with a significant increase in Parkin phosphorylation corresponding to the duration of the TS treatment. (7) ATP synthase and citrate synthase activities were significantly elevated in the TS2 group compared to the control group but were significantly reduced in the TS4 group compared to the TS2 group. In summary, the coordinated regulation of apoptosis, mitochondrial fission and fusion, and particularly mitochondrial autophagy preserved mitochondrial morphology and contributed to the restoration of the activities of these two key mitochondrial enzymes, thereby maintaining liver mitochondrial homeostasis in mice under TS conditions. Full article

(This article belongs to the Special Issue Mitochondrial Medicine: Pharmacological Targeting of Mitochondria in Disease 2.0)

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Influence of TS on morphological data in mice. Numerical values are mean ± standard deviation. n = 8. CON, control group; TS2, tail suspension 2-week group; and TS4, tail suspension 4-week group. ** p < 0.01 and * p < 0.05. Full article ">Figure 2
Histological morphology of mouse liver under different TS treatments. (a) Scale = 100 μm. (b) Scale = 20 μm. Arrows point to hepatocytes. Dashed arrows point to sinusoids. # shows vasculature. Cells within square boxes are necrotic liver cells. CON, control group; TS2, tail suspension 2-week group; and TS4, tail suspension 4-week group. Full article ">Figure 3
Ultrastructure of mouse liver tissue and analysis of mitochondrial number and area under different TS treatments. (a) Scale = 1 μm. * shows mitochondrial autophagic vesicles. Arrows point to mitochondria. (b) Scale = 10 μm. # shows liver nucleus. Arrows point to mitochondria. (c) Number of mitochondria. (d) Mitochondrial cross-sectional area. (e) Mitochondrial area ratio. Numerical values are mean ± standard deviation. Fifteen pictures were analyzed in each group. CON, control group; TS2, tail suspension 2-week group; and TS4, tail suspension 4-week group. ** p < 0.01 and * p < 0.05. Full article ">Figure 4
Activities of ATP synthase (a), CS (b), and Caspase3 (c) in mouse liver under different TS treatments. Numerical values are mean ± standard deviation. n = 8. CON, control group; TS2, tail suspension 2-week group; and TS4, tail suspension 4-week group. ** p < 0.01. Full article ">Figure 5
TUNEL staining of mouse liver under different TS treatments. (a) Scale = 20 μm. Arrows point to DNA fragmentation. Blue fluorescence indicates nuclei; green fluorescence indicates DNA fragmentation. (b) Negative control for TUNEL staining of mouse liver. Scale = 20 μm. CON, control group; TS2, tail suspension 2-week group; and TS4, tail suspension 4-week group. Full article ">Figure 6
Expression levels of liver apoptosis-associated proteins in mice under different TS treatments. (a) Representative Western blot gels. (b) Polyacrylamide gel of total protein. (c) Apoptosis-associated protein level. Numerical values are mean ± standard deviation. n = 8. CON, control group; TS2, tail suspension 2-week group; and TS4, tail suspension 4-week group. * p < 0.05. Full article ">Figure 7
Expression levels of mitochondrial fission- and fusion-associated proteins in mice liver mitochondria under different TS treatments. (a) Representative Western blot gels. (b) Polyacrylamide gel of total protein in the liver. (c) Mitochondrial fission-associated protein levels. (d) Expression levels of mitochondrial fusion-associated proteins. Numerical values are mean ± standard deviation. n = 8. CON, control group; TS2, tail suspension 2-week group; and TS4, tail suspension 4-week group. * p < 0.05. Full article ">Figure 8
Expression levels of autophagy-associated proteins in mouse liver mitochondria under different TS treatments. (a) Representative Western blot gels. (b) Polyacrylamide gel of total protein. (c) Mitochondrial autophagy-associated protein levels. Numerical values are mean ± standard deviation. n = 8. ** p < 0.01 and * p < 0.05. Full article ">Figure 9
Summary of impact of TS on liver mitochondrial homeostasis in mice. bcl2, B-cell lymphoma-2; bax, Bcl-2-associated X protein; caspase3, cysteine aspartic acid-specific protease 3; MFN1, mitofusin 1; MFN2, mitofusin 2; OPA1, optic atrophy 1; MFF, mitochondrial fission factor; DRP1, dynamin-related protein 1; Parkin, Parkinson disease protein 2; P-Parkin, phosphorylated Parkin; ATP synthase, adenosine triphosphate synthase; and CS, citrate synthase. Yellow represents apoptosis-related proteins. Gray represents mitochondrial fusion-related proteins. Pink represents mitochondrial fission-related proteins. Green represents mitochondrial autophagy-related proteins. Blue represents oxidative phosphorylation-related proteins. Red arrows represent up- or down-regulation in TS2 group. Blue arrows represent up- or down-regulation in TS4 group. Full article ">

20 pages, 25074 KiB

Open AccessArticle

Unraveling Magnet Structural Defects in Permanent Magnet Synchronous Machines—Harmonic Diagnosis and Performance Signatures

by Mehdi Abdolmaleki, Pedram Asef and Christopher Vagg

Magnetism 2024, 4(4), 348-367; https://doi.org/10.3390/magnetism4040023 (registering DOI) - 18 Oct 2024

Abstract

Rare-earth-based permanent magnets (PMs) have a vital role in numerous sustainable energy systems, such as electrical machines (EMs). However, their production can greatly harm the environment and their supply chain monopoly presents economic threats. Alternative materials are emerging, but the use of rare-earth PMs remains dominant due to their exceptional performance. Damage to magnet structure can cause loss of performance and efficiency, and propagation of cracks in PMs can result in breaking. In this context, prolonging the service life of PMs and ensuring that they remain damage-free and suitable for re-use is important both for sustainability reasons and cost management. This paper presents a new harmonic content diagnosis and motor performance analysis caused by various magnet structure defects or faults, such as cracked or broken magnets. The proposed method is used for modeling the successive physical failure of the magnet structure in the form of crack formation, crack growth, and magnet breakage. A surface-mounted permanent magnet synchronous motor (PMSM) is studied using simulation in Ansys Maxwell software (Version 2023), and different cracks and PM faults are modeled using the two-dimensional finite element method (FEM). The frequency domain simulation results demonstrate the influence of magnet cracks and their propagation on EM performance measures, such as stator current, distribution of magnetic flux density, back EMF, flux linkage, losses, and efficiency. The results show strong potential for application in health monitoring systems, which could be used to reduce the occurrence of in-service failures, thus reducing the usage of rare-earth magnet materials as well as cost. Full article

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13 pages, 4004 KiB

Open AccessEssay

Genome-Wide Identification and Expression Analysis of the PsTPS Gene Family in Pisum sativum

by Hao Yuan, Baoxia Liu, Guwen Zhang, Zhijuan Feng, Bin Wang, Yuanpeng Bu, Yu Xu, Zhihong Sun, Na Liu and Yaming Gong

Horticulturae 2024, 10(10), 1104; https://doi.org/10.3390/horticulturae10101104 (registering DOI) - 18 Oct 2024

Abstract

This study aimed to explore the role of the trehalose-6-phosphate synthase (TPS) gene family in the adaptation of peas to environmental stress. A comprehensive analysis of the PsTPS gene family identified 20 genes with conserved domains and specific chromosomal locations. Phylogenetic analysis delineated evolutionary relationships, while gene structure analysis revealed compositional insights, and motif analysis provided functional insights. Cis-regulatory element identification predicted gene regulation patterns. Tissue-specific and stress-induced expression profiling highlighted eight genes with ubiquitous expression, with PsTPS15 and PsTPS18 displaying elevated expression levels in roots, nodules, and young stems, and PsTPS13 and PsTPS19 expression downregulated in seeds. Transcriptome analysis identified a differential expression of 20 PsTPS genes, highlighting the significance of 14 genes in response to drought and salinity stress. Notably, under drought conditions, the expression of PsTPS4 and PsTPS6 was initially upregulated and then downregulated, whereas that of PsTPS15 and PsTPS19 was downregulated. Salinity stress notably altered the expression of PsTPS4, PsTPS6, and PsTPS19. Taken together, these findings elucidate the regulatory mechanisms of the PsTPS gene family and their potential as genetic targets for enhancing crop stress tolerance. Full article

(This article belongs to the Section Genetics, Genomics, Breeding, and Biotechnology (G2B2))

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Chromosomal locations of the PsTPS genes on the seven pea chromosomes. The distribution of PsTPS genes is relatively sparse, and they are not distributed on every chromosome. The highest distribution of PsTPS genes is observed on Chr5, which contains seven genes. Full article ">Figure 2
Phylogenetic tree incorporating TPS proteins from Pisum sativum L, Arabidopsis, and Glycine max. The tree of the TPS gene family was constructed by the IQ-TREE 2 software (Version 2.2.0) using the maximum likelihood (ML) method with 1000 bootstrap replicates. The color of the outer ring and branches denote TPS subfamilies. Full article ">Figure 3
The phylogenetic relationship, conserved motifs, and gene structure of PsTPSs. (a) The maximum likelihood (ML) phylogenetic tree of PsTPS proteins was constructed using a full-length sequence with 1000 bootstrap replicates; (b) Distribution of conserved motifs in PsTPS proteins. A total of 10 motifs were predicted, and the scale bar represents 100 aa; (c) Distribution of the TPS domain in PsTPSs; (d) The gene structures of PsTPSs, including introns (black lines) and exons (green rectangles). The scale bar indicates 1000 bp. Full article ">Figure 4
CREs on the putative promoters of PsTPSs. (a) Distribution of CREs identified in the 2000 bp upstream promoter region of PsTPSs; (b) The number of CREs on the putative promoters of PsTPSs. Numbers in the heatmap represent the number of elements. Full article ">Figure 5
Syntenic analyses of TPS genes in Pisum sativum, Arabidopsis, G. max. (a) Seven chromosomes from Pisum sativum (Ps1–Ps7) are mapped, with chromosome length expressed as Mb. Lines denote syntenic TPS gene pairs on the chromosomes. (b) The seven chromosomes of Pisum sativum (Ps1–7), five chromosomes of A. thaliana (At1–5), and twenty chromosomes of G. max (Gm1–20) are mapped. Lines represent syntenic TPS gene pairs. Full article ">Figure 6
Predicted protein–protein interaction networks of PsTPS proteins with other proteins using the STRING tool. Interactions between proteins are represented by gray lines. Full article ">Figure 7
Expression profiles of the eight PsTPS genes. The color scale from blue to red indicates increasing log2-transformed FPKM values. Full article ">Figure 8
Transcriptome analysis depicting the expression levels of 14 PsTPS genes in Pisum sativum under drought stress conditions induced by 10%, 20%, and 30% PEG6000 and salt stress induced by 100 mM, 200 mM, and 300 mM NaCl. Each experiment was conducted independently with a minimum of three replicates. “CK_0h” denotes the control group. Full article ">

18 pages, 4253 KiB

Open AccessArticle

The D75N and P161S Mutations in the C0-C2 Fragment of cMyBP-C Associated with Hypertrophic Cardiomyopathy Disturb the Thin Filament Activation, Nucleotide Exchange in Myosin, and Actin–Myosin Interaction

by Anastasia M. Kochurova, Evgenia A. Beldiia, Victoria V. Nefedova, Daria S. Yampolskaya, Natalia A. Koubassova, Sergey Y. Kleymenov, Julia Y. Antonets, Natalia S. Ryabkova, Ivan A. Katrukha, Sergey Y. Bershitsky, Alexander M. Matyushenko, Galina V. Kopylova and Daniil V. Shchepkin

Int. J. Mol. Sci. 2024, 25(20), 11195; https://doi.org/10.3390/ijms252011195 (registering DOI) - 18 Oct 2024

Abstract

About half of the mutations that lead to hypertrophic cardiomyopathy (HCM) occur in the MYBPC3 gene. However, the molecular mechanisms of pathogenicity of point mutations in cardiac myosin-binding protein C (cMyBP-C) remain poorly understood. In this study, we examined the effects of the D75N and P161S substitutions in the C0 and C1 domains of cMyBP-C on the structural and functional properties of the C0-C1-m-C2 fragment (C0-C2). Differential scanning calorimetry revealed that these mutations disorder the tertiary structure of the C0-C2 molecule. Functionally, the D75N mutation reduced the maximum sliding velocity of regulated thin filaments in an in vitro motility assay, while the P161S mutation increased it. Both mutations significantly reduced the calcium sensitivity of the actin–myosin interaction and impaired thin filament activation by cross-bridges. D75N and P161S C0-C2 fragments substantially decreased the sliding velocity of the F-actin-tropomyosin filament. ADP dose-dependently reduced filament sliding velocity in the presence of WT and P161S fragments, but the velocity remained unchanged with the D75N fragment. We suppose that the D75N mutation alters nucleotide exchange kinetics by decreasing ADP affinity to the ATPase pocket and slowing the myosin cycle. Our molecular dynamics simulations mean that the D75N mutation affects myosin S1 function. Both mutations impair cardiac contractility by disrupting thin filament activation. The results offer new insights into the HCM pathogenesis caused by missense mutations in N-terminal domains of cMyBP-C, highlighting the distinct effects of D75N and P161S mutations on cardiac contractile function. Full article

(This article belongs to the Special Issue Research Progress on the Mechanism and Treatment of Cardiomyopathy)

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Temperature dependences of excess heat capacity (Cp) monitored by DSC for the WT C0-C2 fragment and C0-C2 fragments with D75N and P161S mutations. Full article ">Figure 2
Binding of C0-C2 fragments to F-actin. (a) Examples of images of F-actin bound to the flow cell surface at 100 nM, 300 nM, and 500 nM loading concentrations of C0-C2 fragments. (b) The dependence of the mean fluorescence intensity in the microscope field of view on the C0-C2 fragment concentration. The intensity was averaged by 10 fields of view in three experiments. Experimental data (mean ± SD) were fitted using the Hill equation corresponding fits shown as lines. Full article ">Figure 3
Effects of cMyBP-C mutations in the N-terminal part of cMyBP-C on the actin–myosin interaction. (a) Dependence of the sliding velocity of thin filaments over myosin in the in vitro motility assay on the C0-C2 fragment loading concentration at pCa4. (b) Calcium dependence of the sliding velocity of thin filaments over myosin. (c) Effect of cMyBP-C mutations on the relationship between the thin filament sliding velocity and myosin concentration at pCa4. (d) Influence of cMyBP-C mutations on the dependence of the sliding velocity of F-actin–Tpm filaments on myosin concentration. In (a), the experimental data (mean ± SD) are fitted by the logistic function. In (b–d), the data (mean ± SD) are fitted to the Hill equation. The equation parameters are given in <a href="#ijms-25-11195-t001" class="html-table">Table 1</a> and <a href="#ijms-25-11195-t002" class="html-table">Table 2</a>. Full article ">Figure 4
Effect of saturated Ca2+ concentration on the sliding velocity of F-actin over myosin in the presence of 500 nM cMyBP-C fragments. The velocity is presented as the mean ± SD. The symbol * indicates the statistically significant difference between the sliding velocity of F-actin at saturating Ca2+ concentration (+Ca2+) from those without Ca2+ (−Ca2+), p < 0.05. Statistical significance was estimated using the Student’s t-test. Full article ">Figure 5
(a) Dependence of the sliding velocity of thin filaments on the ATP concentration. The experimental data are fitted to the Hill equation. (b) Dependence of the sliding velocity of thin filaments on the ADP concentration. The experimental data (mean ± SD) for 500 nM D75N C0-C2 fragment are fitted by a linear function; experimental data (mean ± SD) for 0 nM WT C0-C2 fragment, 500 nM WT C0-C2 fragment, and 500 nM P161S C0-C2 fragment were fitted to the Hill equation. The values of the ATP and ADP concentration, at which the velocity was half-maximal, are given in <a href="#ijms-25-11195-t003" class="html-table">Table 3</a>. Full article ">Figure 6
(a) The minimal distance between Glu2, first charged N-terminal residue of C0 domain, and actin surface in MD trajectory. (b,c) Fluctuations of Tpm strands from the actin helix shown as standard deviations of the mean of the azimuthal angles of the residues in two chains of the Tpm strand 1 and 2, respectively, from the actin helix defined by the positions of the K328 residues in the corresponding long pseudo-helical actin strand. Full article ">

28 pages, 2807 KiB

Open AccessArticle

The Mechanism of Tendentious Information Dissemination in Cyberspace

by Teng Zong, Bing Chen, Fengsi Wang, Xin Wei, Yibo Liu, Zongmin Hu and Taowei Li

Appl. Sci. 2024, 14(20), 9505; https://doi.org/10.3390/app14209505 (registering DOI) - 18 Oct 2024

Abstract

Cyberspace has evolved into a hub for the dissemination of large amounts of tendentious information, posing significant challenges to the role of mainstream value information. As netizens’ are the main recipients of tendentious information, their personal cognition, attitude, and behavioral ability affect their willingness to re-disseminate information, making them an inalienable force in the promotion of information dissemination. Exploring the dissemination mechanism of tendentious information in cyberspace can help to understand the law of information dissemination and predict the trend of information diffusion, which is of great significance to maintaining information security and social stability. However, the existing research has overlooked the potential influence of the attribute characteristics of information in terms of content, and has failed to overcome the methodological constraints of traditional statistical analysis to accurately describe the variables and mechanisms influencing the dissemination of tendentious information at the cognitive level. Therefore, using structural equation modeling, we propose a research index system based on the Theory of Planned Behavior and the characteristics of tendentious information. To this end, confirmatory factor and model fitting analyses were conducted to develop a tendentious information dissemination mechanism model, which we validated through testing and comparative experiments. Path analysis revealed that Attitude Toward Dissemination, Information Dissemination Intention, and Information Dissemination Behavior are the main links in the information dissemination process. Moreover, Information Sentiment Orientation was found to strongly promote the dissemination of tendentious information, while Subject Norm of Dissemination had a minor inhibiting effect. Full article

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Theoretical framework for examining the dissemination mechanism of tendentious information. Full article ">Figure 2
Model hypotheses for researching the mechanism of tendentious information dissemination. Full article ">Figure 3
Flowchart of tendentious information dissemination analysis. Full article ">Figure 4
The measurement model (ATD). Full article ">Figure 5
Final TIDM model. Full article ">Figure 6
Model comparison based on different modeling theories: (a) based on TIDM and (b) based on TPB. Full article ">Figure 7
Model comparison based on different modeling methods: (a) based on structural equation modeling and (b) based on traditional statistical modeling. Full article ">Figure 8
Cross-validation based on different data samples: (a) N = 227 and (b) N = 516. Full article ">

14 pages, 546 KiB

Open AccessArticle

Ethnobotanical and Ethnopharmacological Study of Paris polyphylla var. yunnanensis in Yunnan Province, China

by Xiuxiang Yan, Angkhana Inta, Ge Li, Hataichanok Pandith, Terd Disayathanoowat and Lixin Yang

Plants 2024, 13(20), 2914; https://doi.org/10.3390/plants13202914 (registering DOI) - 18 Oct 2024

Abstract

The traditional medicinal knowledge in the northwest of Yunnan Province, China have been poorly studied. Paris polyphylla var. yunnanensis (PPvY) is widely cultivated and used as indigenous traditional Chinese medicine (TCM) to treat cancer in northwest Yunnan. This study aims to reveal the traditional medicinal knowledge of PPvY and folk formulas related to PPvY through literature research and ethnobotanical investigation. Semi-structured interviews were conducted with 14 highly regarded folk doctors in the northwest of Yunnan, China, based on relevant data collected in the initial phase of the research. We identified twenty-three traditional treatments, thirty pairing herbs used with PPvY in therapy, and eight processing methods of PPvY. The results indicated that PPvY and its associated formulas containing PPvY were primarily used for treating cancer and inflammation and for clearing heat and detoxifying. The TCM herbs most frequently used alongside PPvY included Engleromyces sinensis and Glycyrrhiza yunnanensis. The commonly employed processing methods primarily involved using PPvY in both its dry and fresh forms, while special processing methods, such as processing in wine and honey, steaming, and foil-packet boiling, were worth further research. Our results highlight the diversity of medicinal plants and the richness of traditional medical knowledge in northwest Yunnan, China. This study may offer clues for the development and research of indigenous medicinal plants. Additionally, a collective effort is needed to create a plan for the sustainable use of indigenous medicinal plants, enhancing local economic development while safeguarding biodiversity and traditional medicinal knowledge. Full article

(This article belongs to the Special Issue Valuable Sources of Bioactive Natural Products from Plants, 2nd Edition)

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Location map of study sites in northwest Yunnan, China. The red star indicates the survey sites. The green circle indicates the location of the snow mountains. The blue lines represent the Jinsha River. Full article ">

12 pages, 6333 KiB

Open AccessArticle

Tribological and Corrosion Properties of Al₂O₃@Y₂O₃-Reinforced Ni60A Composite Coatings Deposited Using Laser Cladding

by Yu Yin, Xing-Hua Ma, Jingwei Li, Shuling Zhang, Zihao Yin, Minghao Ma and Feng Guo

Coatings 2024, 14(10), 1334; https://doi.org/10.3390/coatings14101334 (registering DOI) - 18 Oct 2024

Abstract

Since rare earth oxides and hard ceramic particles improve coating quality, a novel Al₂O₃@Y₂O₃ core–shell structure was prepared. Then, Ni60A coatings with different amounts (2~6 wt.%) of Al₂O₃@Y₂O₃ core–shell structures were prepared using laser cladding technology on an H13 steel surface. To demonstrate the unique effect of the core–shell structure on the performance of the coatings, a set of controlled experiments was also conducted with different proportions of Al₂O₃-Y₂O₃ mechanically mixed powders. The effect of Al₂O₃@Y₂O₃ addition on the phase composition, element distribution, microstructure, wear, and corrosion resistance of the coatings was characterized and tested thoroughly. By comparing the forming quality, hardness, wear, and corrosion resistance of the different coatings, 2 wt.% was confirmed as the optimal concentration of Al₂O₃@Y₂O₃, and its corresponding friction coefficient was about 0.44. The wear rate was approximately 4.15 × 10⁻³ mm³·(N·m)⁻¹, the self-corrosion potential was around −0.3659 V, and the self-corrosion current density was about 1.248 × 10⁻⁶ A·cm⁻². Full article

(This article belongs to the Section Laser Coatings)

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20 pages, 3549 KiB

Open AccessReview

Rare-Earth Metal-Based Materials for Hydrogen Storage: Progress, Challenges, and Future Perspectives

by Yaohui Xu, Xi Yang, Yuting Li, Yu Zhao, Xing Shu, Guoying Zhang, Tingna Yang, Yitao Liu, Pingkeng Wu and Zhao Ding

Nanomaterials 2024, 14(20), 1671; https://doi.org/10.3390/nano14201671 (registering DOI) - 18 Oct 2024

Abstract

Rare-earth-metal-based materials have emerged as frontrunners in the quest for high-performance hydrogen storage solutions, offering a paradigm shift in clean energy technologies. This comprehensive review delves into the cutting-edge advancements, challenges, and future prospects of these materials, providing a roadmap for their development and implementation. By elucidating the fundamental principles, synthesis methods, characterization techniques, and performance enhancement strategies, we unveil the immense potential of rare-earth metals in revolutionizing hydrogen storage. The unique electronic structure and hydrogen affinity of these elements enable diverse storage mechanisms, including chemisorption, physisorption, and hydride formation. Through rational design, nanostructuring, surface modification, and catalytic doping, the hydrogen storage capacity, kinetics, and thermodynamics of rare-earth-metal-based materials can be significantly enhanced. However, challenges such as cost, scalability, and long-term stability need to be addressed for their widespread adoption. This review not only presents a critical analysis of the state-of-the-art but also highlights the opportunities for multidisciplinary research and innovation. By harnessing the synergies between materials science, nanotechnology, and computational modeling, rare-earth-metal-based hydrogen storage materials are poised to accelerate the transition towards a sustainable hydrogen economy, ushering in a new era of clean energy solutions. Full article

(This article belongs to the Special Issue Featured Reviews in Physical Chemistry at Nanoscale)

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