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Perspective
Ethically Researching Local Impacts of Environmental Change without Travel
Geosciences 2021, 11(8), 316; https://doi.org/10.3390/geosciences11080316 (registering DOI) - 27 Jul 2021
Abstract
Responses to the COVID-19 pandemic, which began in 2020, included local and international travel restrictions alongside limits on face-to-face gatherings. These measures impinged on participatory research examining local impacts of environmental change. In response, many researchers adopted techniques that could be implemented without [...] Read more.
Responses to the COVID-19 pandemic, which began in 2020, included local and international travel restrictions alongside limits on face-to-face gatherings. These measures impinged on participatory research examining local impacts of environmental change. In response, many researchers adopted techniques that could be implemented without travel. This article explores some of the consequent research ethics issues. Full article
(This article belongs to the Collection Ethics in Geosciences)
Article
Antioxidant Effect of Lonicera caerulea L. in the Cardiovascular System of Obese Zucker Rats
Antioxidants 2021, 10(8), 1199; https://doi.org/10.3390/antiox10081199 (registering DOI) - 27 Jul 2021
Abstract
Background: Lonicera caerulea L. (Loni) represents a promising source of beneficial polyphenols with therapeutical potential in cardiovascular diseases. We aimed to study the effects of Loni and coenzyme Q10 (CoQ10) on selected cardiometabolic parameters and NO/ROS balance in obese Zucker rats. Methods: Male [...] Read more.
Background: Lonicera caerulea L. (Loni) represents a promising source of beneficial polyphenols with therapeutical potential in cardiovascular diseases. We aimed to study the effects of Loni and coenzyme Q10 (CoQ10) on selected cardiometabolic parameters and NO/ROS balance in obese Zucker rats. Methods: Male Zucker rats were divided into the control group and groups treated with CoQ10 (30 mg/kg/day) or Loni (5 g/kg/day) for 6 weeks. Blood pressure, body weight, heart weight, and plasma lipid profile were determined. NOS activity and protein expressions of eNOS, SOD, NADPH oxidase, and NF-kappa B were measured in the heart and aorta. Results: Neither body weight nor blood pressure were significantly changed after six weeks of Loni or CoQ10 treatment. Both Loni and CoQ10 decreased the plasma LDL level. Moreover, Loni decreased the total cholesterol level. The total NOS activity did not change in the heart after the treatments. However, in the aorta, Loni treatment increased NOS activity and protein expression of SOD and decreased expressions of NADPH oxidase and NF-kappa B compared to both the control and CoQ10 groups. There were no changes in the eNOS protein expression within the groups. In conclusion, it seems that the antioxidant effect of Loni was responsible for both the decrease of plasma LDL and the total cholesterol levels and the increase of vascular NOS activity. Full article
(This article belongs to the Special Issue Antioxidant Foods and Cardiometabolic Health)
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Article
Meat Quality of the Native Carpathian Goat Breed in Comparison with the Saanen Breed
Animals 2021, 11(8), 2220; https://doi.org/10.3390/ani11082220 (registering DOI) - 27 Jul 2021
Abstract
Goats provide valuable products that are appreciated by consumers who are looking for food that is not only tasty but also healthy, and, probably, one of them is goat meat. Breeding of local breeds such as the native Carpathian goat has been gaining [...] Read more.
Goats provide valuable products that are appreciated by consumers who are looking for food that is not only tasty but also healthy, and, probably, one of them is goat meat. Breeding of local breeds such as the native Carpathian goat has been gaining importance in recent years, which creates an opportunity for the development of the goat meat market. The aim of this study was to investigate the influence of goat breed on the basic chemical, fatty and amino acid composition, colour and sensory evaluation of meat. The research material consisted of Carpathian goats from the NRIAP experimental plant located in the southern part of Poland, and goats from a farm keeping Saanen goats in south-eastern Poland. Ten male goat kids from each breed were taken to the NRIAP farm. The quality of meat obtained from the leg (m. biceps femoris) of male goat kids about 150 days old at slaughter was analysed. The meat of the Carpathian goat was characterised by a lower content of protein and cholesterol (p < 0.01), and a higher content of fat and general collagen compared to the meat from Saanen goats (p < 0.05). Cholesterol content in goat meat of both breeds was similar and ranged from 55.08 mg/100 g (Carpathian) to 56.79 mg/100 g (Saanen). Despite the higher collagen content, the goat meat of Carpathian breeds was characterised by lower shear force, less hardness (p < 0.05) and chewiness, being a more delicate meat. The fat of Carpathian goat breeds was characterised by a higher content of monounsaturated acids, mainly C 18:1n:9, and a more favourable (lower) saturation index, S/P (p < 0.05). The meat of Carpathian goats was characterised by a higher health-promoting quality compared to the meat from Saanen goats. In the goat meat of both breeds, there were no differences between the total content of exogenous and endogenous amino acids. The essential/nonessential amino acids (EAA/NEAA) ratio in the meat of the analysed breeds was 0.88:0.89. However, the meat of the Carpathian goats was statistically significantly higher concerning the content of phenylalanine, histidine, proline, alanine and tyrosine, as compared to the meat of the Saanen goats. The obtained results confirm the high quality of the meat of the local Carpathian breed in comparison to the Saanen breed. Full article
(This article belongs to the Special Issue Carcass Composition and Meat Quality of Small Ruminants)
Article
Antibodies Enhance the Suppressive Activity of Extracellular Vesicles in Mouse Delayed-Type Hypersensitivity
Pharmaceuticals 2021, 14(8), 734; https://doi.org/10.3390/ph14080734 (registering DOI) - 27 Jul 2021
Abstract
Previously, we showed that mouse delayed-type hypersensitivity (DTH) can be antigen-specifically downregulated by suppressor T cell-derived miRNA-150 carried by extracellular vesicles (EVs) that target antigen-presenting macrophages. However, the exact mechanism of the suppressive action of miRNA-150-targeted macrophages on effector T cells remained unclear, [...] Read more.
Previously, we showed that mouse delayed-type hypersensitivity (DTH) can be antigen-specifically downregulated by suppressor T cell-derived miRNA-150 carried by extracellular vesicles (EVs) that target antigen-presenting macrophages. However, the exact mechanism of the suppressive action of miRNA-150-targeted macrophages on effector T cells remained unclear, and our current studies aimed to investigate it. By employing the DTH mouse model, we showed that effector T cells were inhibited by macrophage-released EVs in a miRNA-150-dependent manner. This effect was enhanced by the pre-incubation of EVs with antigen-specific antibodies. Their specific binding to MHC class II-expressing EVs was proved in flow cytometry and ELISA-based experiments. Furthermore, by the use of nanoparticle tracking analysis and transmission electron microscopy, we found that the incubation of macrophage-released EVs with antigen-specific antibodies resulted in EVs’ aggregation, which significantly enhanced their suppressive activity in vivo. Nowadays, it is increasingly evident that EVs play an exceptional role in intercellular communication and selective cargo transfer, and thus are considered promising candidates for therapeutic usage. However, EVs appear to be less effective than their parental cells. In this context, our current studies provide evidence that antigen-specific antibodies can be easily used for increasing EVs’ biological activity, which has great therapeutic potential. Full article
Article
Transient Current Density in a Pair of Long Parallel Conductors
Appl. Sci. 2021, 11(15), 6920; https://doi.org/10.3390/app11156920 (registering DOI) - 27 Jul 2021
Abstract
Two infinitely long parallel conductors of arbitrary cross section connected to a voltage source form a loop. If the source voltage depends on time, then due to induction there is no constant current density in the loop conductors. It is only recently that [...] Read more.
Two infinitely long parallel conductors of arbitrary cross section connected to a voltage source form a loop. If the source voltage depends on time, then due to induction there is no constant current density in the loop conductors. It is only recently that a method has been published for accurately calculating current density in a group of long parallel conductors. The method has thus far been applied to the calculation of steady-state current density in a loop connected to a sinusoidal voltage source. In the present article, the method is used for an accurate calculation of transient current using transient current density. The transient current is analysed when connecting and short-circuiting the sources of sinusoidal, constant and sawtooth voltages. For circular cross section conductors, the dependences of maximum current density, maximum current and the time of achieving steady state on the source frequency, the distance of the conductors and their resistivity when connecting the source of sinusoidal voltage are examined. Full article
(This article belongs to the Section Electrical, Electronics and Communications Engineering)
Article
Determination of a Tentative Epidemiological Cut-Off Value (ECOFF) for Dalbavancin and Enterococcus faecium
Antibiotics 2021, 10(8), 915; https://doi.org/10.3390/antibiotics10080915 (registering DOI) - 27 Jul 2021
Abstract
Dalbavancin is a lipoglycopeptide antibiotic that shows potent activity against Gram-positive bacteria. It circumvents vanB-type glycopeptide resistance mechanisms; however, data on the in vitro activity of dalbavancin for Enterococcus faecium (E. faecium) are scarce, and thus, no breakpoints are provided. [...] Read more.
Dalbavancin is a lipoglycopeptide antibiotic that shows potent activity against Gram-positive bacteria. It circumvents vanB-type glycopeptide resistance mechanisms; however, data on the in vitro activity of dalbavancin for Enterococcus faecium (E. faecium) are scarce, and thus, no breakpoints are provided. In recent years, there has been a continuing shift from vanA-type to vanB-type vancomycin-resistance in enterococci in Central Europe. Therefore, we aimed to investigate the in vitro activity of dalbavancin against different van-genotypes, with particular focus on vanB-type E. faecium. Dalbavancin susceptibility was determined for 25 van-negative, 50 vanA-positive, and 101 vanB-positive clinical E. faecium isolates (typed by cgMLST). Epidemiological Cut-Off Values (ECOFFs) were determined using ECOFFinder. For vanB-type E. faecium isolates, dalbavancin MICs were similar to those of vancomycin-susceptible isolates reaching values no higher than 0.125 mg/L. ECOFFs for van-negative and vanB-positive isolates were 0.5 mg/l and 0.25 mg/L respectively. In contrast, E. faecium possessing vanA predominantly showed dalbavancin MICs >8 mg/L, therefore preventing the determination of an ECOFF. We demonstrated the potent in vitro activity of dalbavancin against vancomycin-susceptible and vanB-type E. faecium. On the basis of the observed wildtype distribution, a dalbavancin MIC of 0.25 mg/L can be suggested as a tentative ECOFF for E. faecium. Full article
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Article
Spectroscopic Studies of Laser-Based Far-Ultraviolet Plasma Light Source
Appl. Sci. 2021, 11(15), 6919; https://doi.org/10.3390/app11156919 (registering DOI) - 27 Jul 2021
Abstract
A series of experiments is described which were conducted to measure the absolute spectral irradiances of laser plasmas created from metal targets over the wavelength region of 123–164 nm by two separate 1.0 μm lasers, i.e., using 100 Hz, 10 ns, 2–20 kHz, 60–100 ns full-width-at-half-maximum pulses. A maximum radiation conversion efficiency of ≈ 3%/2πsr is measured over a wavelength region from ≈ 125 to 160 nm. A developed collisional-radiative solver and radiation-hydrodynamics simulations in comparison to the spectra detected by the Seya–Namioka-type monochromator reveal the strong broadband experimental radiations which mainly originate from bound–bound transitions of low-ionized charges superimposed on a strong continuum from a dense plasma with an electron temperature of less than 10 eV. Full article
(This article belongs to the Section Applied Physics)
Article
On the Role of Cs4PbBr6 Phase in the Luminescence Performance of Bright CsPbBr3 Nanocrystals
Nanomaterials 2021, 11(8), 1935; https://doi.org/10.3390/nano11081935 (registering DOI) - 27 Jul 2021
Abstract
CsPbBr3 nanocrystals have been identified as a highly promising material for various optoelectronic applications. However, they tend to coexist with Cs4PbBr6 phase when the reaction conditions are not controlled carefully. It is therefore imperative to understand how the presence [...] Read more.
CsPbBr3 nanocrystals have been identified as a highly promising material for various optoelectronic applications. However, they tend to coexist with Cs4PbBr6 phase when the reaction conditions are not controlled carefully. It is therefore imperative to understand how the presence of this phase affects the luminescence performance of CsPbBr3 nanocrystals. We synthesized a mixed CsPbBr3-Cs4PbBr6 sample, and compared its photo- and radioluminescence properties, including timing characteristics, to the performance of pure CsPbBr3 nanocrystals. The possibility of energy transfer between the two phases was also explored. We demonstrated that the presence of Cs4PbBr6 causes significant drop in radioluminescence intensity of CsPbBr3 nanocrystals, which can limit possible future applications of Cs4PbBr6-CsPbBr3 mixtures or composites as scintillation detectors. Full article
(This article belongs to the Special Issue Luminescent Nanomaterials and Their Applications)
Article
Stability of Methylphenidate under Various pH Conditions in the Presence or Absence of Gut Microbiota
Pharmaceuticals 2021, 14(8), 733; https://doi.org/10.3390/ph14080733 (registering DOI) - 27 Jul 2021
Abstract
Methylphenidate is one of the most widely used oral treatments for attention-deficit/hyperactivity disorder (ADHD). The drug is mainly absorbed in the small intestine and has low bioavailability. Accordingly, a high interindividual variability in terms of response to the treatment is known among ADHD [...] Read more.
Methylphenidate is one of the most widely used oral treatments for attention-deficit/hyperactivity disorder (ADHD). The drug is mainly absorbed in the small intestine and has low bioavailability. Accordingly, a high interindividual variability in terms of response to the treatment is known among ADHD patients treated with methylphenidate. Nonetheless, very little is known about the factors that influence the drug’s absorption and bioavailability. Gut microbiota has been shown to reduce the bioavailability of a wide variety of orally administered drugs. Here, we tested the ability of small intestinal bacteria to metabolize methylphenidate. In silico analysis identified several small intestinal bacteria to harbor homologues of the human carboxylesterase 1 enzyme responsible for the hydrolysis of methylphenidate in the liver into the inactive form, ritalinic acid. Despite our initial results hinting towards possible bacterial hydrolysis of the drug, up to 60% of methylphenidate is spontaneously hydrolyzed in the absence of bacteria and this hydrolysis is pH-dependent. Overall, our results indicate that the stability of methylphenidate is compromised under certain pH conditions in the presence or absence of gut microbiota. Full article
(This article belongs to the Section Pharmacology)
Article
Towards Robust Representations of Spatial Networks Using Graph Neural Networks
Appl. Sci. 2021, 11(15), 6918; https://doi.org/10.3390/app11156918 (registering DOI) - 27 Jul 2021
Abstract
The effectiveness of a machine learning model is impacted by the data representation used. Consequently, it is crucial to investigate robust representations for efficient machine learning methods. In this paper, we explore the link between data representations and model performance for inference tasks [...] Read more.
The effectiveness of a machine learning model is impacted by the data representation used. Consequently, it is crucial to investigate robust representations for efficient machine learning methods. In this paper, we explore the link between data representations and model performance for inference tasks on spatial networks. We argue that representations which explicitly encode the relations between spatial entities would improve model performance. Specifically, we consider homogeneous and heterogeneous representations of spatial networks. We recognise that the expressive nature of the heterogeneous representation may benefit spatial networks and could improve model performance on certain tasks. Thus, we carry out an empirical study using Graph Neural Network models for two inference tasks on spatial networks. Our results demonstrate that heterogeneous representations improves model performance for down-stream inference tasks on spatial networks. Full article
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Article
Contextuality in Classical Physics and Its Impact on the Foundations of Quantum Mechanics
Entropy 2021, 23(8), 968; https://doi.org/10.3390/e23080968 (registering DOI) - 27 Jul 2021
Abstract
It is shown that the hallmark quantum phenomenon of contextuality is present in classical statistical mechanics (CSM). It is first shown that the occurrence of contextuality is equivalent to there being observables that can differentiate between pure and mixed states. CSM is formulated [...] Read more.
It is shown that the hallmark quantum phenomenon of contextuality is present in classical statistical mechanics (CSM). It is first shown that the occurrence of contextuality is equivalent to there being observables that can differentiate between pure and mixed states. CSM is formulated in the formalism of quantum mechanics (FQM), a formulation commonly known as the Koopman–von Neumann formulation (KvN). In KvN, one can then show that such a differentiation between mixed and pure states is possible. As contextuality is a probabilistic phenomenon and as it is exhibited in both classical physics and ordinary quantum mechanics (OQM), it is concluded that the foundational issues regarding quantum mechanics are really issues regarding the foundations of probability. Full article
(This article belongs to the Special Issue Quantum Probability and Randomness III)
Review
Free Amino Acid Alterations in Patients with Gynecological and Breast Cancer: A Review
Pharmaceuticals 2021, 14(8), 731; https://doi.org/10.3390/ph14080731 (registering DOI) - 27 Jul 2021
Abstract
Gynecological and breast cancers still remain a significant health problem worldwide. Diagnostic methods are not sensitive and specific enough to detect the disease at an early stage. During carcinogenesis and tumor progression, the cellular need for DNA and protein synthesis increases leading to [...] Read more.
Gynecological and breast cancers still remain a significant health problem worldwide. Diagnostic methods are not sensitive and specific enough to detect the disease at an early stage. During carcinogenesis and tumor progression, the cellular need for DNA and protein synthesis increases leading to changes in the levels of amino acids. An important role of amino acids in many biological pathways, including biosynthesis of proteins, nucleic acids, enzymes, etc., which serve as an energy source and maintain redox balance, has been highlighted in many research articles. The aim of this review is a detailed analysis of the literature on metabolomic studies of gynecology and breast cancers with particular emphasis on alterations in free amino acid profiles. The work includes a brief overview of the metabolomic methodology and types of biological samples used in the studies. Special attention was paid to the possible role of selected amino acids in the carcinogenesis, especially proline and amino acids related to its metabolism. There is a clear need for further research and multiple external validation studies to establish the role of amino acid profiling in diagnosing gynecological and breast cancers. Full article
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Article
A Composite Membrane System with Gold Nanoparticles, Hydroxyapatite, and Fullerenol for Dual Interaction for Biomedical Purposes
Membranes 2021, 11(8), 565; https://doi.org/10.3390/membranes11080565 (registering DOI) - 27 Jul 2021
Abstract
Background: Wound dressing plays a vital role in post-operative aftercare. There is the necessity to develop dressings for application on the border of soft and hard tissue. This study aimed to develop multifunctional polyelectrolyte layers enhanced by hydroxyapatite nanoparticles, gold nanoparticles (AuNPs), and/or [...] Read more.
Background: Wound dressing plays a vital role in post-operative aftercare. There is the necessity to develop dressings for application on the border of soft and hard tissue. This study aimed to develop multifunctional polyelectrolyte layers enhanced by hydroxyapatite nanoparticles, gold nanoparticles (AuNPs), and/or fullerenol nanocomposites to achieve a wound dressing that could be applied on the bone-skin interface. Methods: Constructed shells were examined using TEM, STEM, and EDX techniques. The human osteoblasts or fibroblasts were immobilized within the shells. The systems morphology was assessed using SEM. The functioning of cells was determined by flow cytomery. Moreover, the internalization of AuNPs was assessed. Results: Involvement of fullerenol and/or hydroxyapatite nanoparticles influenced the immobilized cell systems morphology. Membranes with fullerenol and hydroxyapatite nanoparticles were observed to block the internalization of AuNPs by immobilized hFOB cells. Conclusions: The designed bilayer membranes incorporating fullerenol, and bacteriostatic elements, prevented the internalization of AuNPs by hFOB cells and ensured the proper counts and morphology of eukaryotic cells. The developed material can be recommended for dressings at the bone-skin interface. Full article
(This article belongs to the Special Issue Membrane Systems for Biomedical Engineering)
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Article
Testing Strategies of the In Vitro Micronucleus Assay for the Genotoxicity Assessment of Nanomaterials in BEAS-2B Cells
Nanomaterials 2021, 11(8), 1929; https://doi.org/10.3390/nano11081929 (registering DOI) - 27 Jul 2021
Abstract
The evaluation of the frequency of micronuclei (MN) is a broadly utilised approach in in vitro toxicity testing. Nevertheless, the specific properties of nanomaterials (NMs) give rise to concerns regarding the optimal methodological variants of the MN assay. In bronchial epithelial cells (BEAS-2B), [...] Read more.
The evaluation of the frequency of micronuclei (MN) is a broadly utilised approach in in vitro toxicity testing. Nevertheless, the specific properties of nanomaterials (NMs) give rise to concerns regarding the optimal methodological variants of the MN assay. In bronchial epithelial cells (BEAS-2B), we tested the genotoxicity of five types of NMs (TiO2: NM101, NM103; SiO2: NM200; Ag: NM300K, NM302) using four variants of MN protocols, differing in the time of exposure and the application of cytochalasin-B combined with the simultaneous and delayed co-treatment with NMs. Using transmission electron microscopy, we evaluated the impact of cytochalasin-B on the transport of NMs into the cells. To assess the behaviour of NMs in a culture media for individual testing conditions, we used dynamic light scattering measurement. The presence of NMs in the cells, their intracellular aggregation and dispersion properties were comparable when tests with or without cytochalasin-B were performed. The genotoxic potential of various TiO2 and Ag particles differed (NM101 < NM103 and NM302 < NM300K, respectively). The application of cytochalasin-B tended to increase the percentage of aberrant cells. In conclusion, the comparison of the testing strategies revealed that the level of DNA damage induced by NMs is affected by the selected methodological approach. This fact should be considered in the interpretation of the results of genotoxicity tests. Full article
(This article belongs to the Special Issue Genotoxicity of Nanomaterials)
Article
Antioxidant Enzyme Activities Correlated with Growth Parameters of Wheat Sprayed with Silver and Gold Nanoparticle Suspensions
Agronomy 2021, 11(8), 1494; https://doi.org/10.3390/agronomy11081494 (registering DOI) - 27 Jul 2021
Abstract
Application of nanotechnology is crucial for a sustainable increase in food production to cope with the increasing food demand of the burgeoning population. Wheat production has to increase significantly for food security in Pakistan with the help of nanotechnology. In biological systems, utilization [...] Read more.
Application of nanotechnology is crucial for a sustainable increase in food production to cope with the increasing food demand of the burgeoning population. Wheat production has to increase significantly for food security in Pakistan with the help of nanotechnology. In biological systems, utilization of nanoparticles has been increased due to their growth-promoting effects on germination, photosynthetic attributes, nutrient use efficiency and metabolic activities. An experiment was conducted with the objective to establish a relationship between growth parameters and antioxidant enzyme activity in response to silver (Ag) and gold (Au) nanoparticles (NPs). Application of Ag (20 mg/L) and Au NPs (10 mg/L) significantly enhanced the antioxidant enzyme activities of ascorbate peroxidase, catalase and guaiacol peroxidase. Consequently, growth parameters: fresh and dry biomass, leaf area, chlorophyll (a, b) and total chlorophyll contents, also increased significantly. These results suggest that application of Ag and Au NPs has the potential to promote wheat growth through enhancing the antioxidant enzyme activities. Full article
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Article
SBS Modified Bitumen with Organic Layered Double Hydroxides: Compatibility and Aging Effects on Rheological Properties
Materials 2021, 14(15), 4201; https://doi.org/10.3390/ma14154201 (registering DOI) - 27 Jul 2021
Abstract
SBS-modified bitumen (SMB) is susceptible to aging, which seriously influences its service performance and life. In order to strengthen the anti-aging ability of SMB, triethoxyvinylsilane was designed to organically modify layered double hydroxides (LDHs) and was applied to modify SMB. The dispersibility and [...] Read more.
SBS-modified bitumen (SMB) is susceptible to aging, which seriously influences its service performance and life. In order to strengthen the anti-aging ability of SMB, triethoxyvinylsilane was designed to organically modify layered double hydroxides (LDHs) and was applied to modify SMB. The dispersibility and storage stability of LDHs in SMB were markedly enhanced after triethoxyvinylsilane organic modification, and the compatibility and storage stability of SBS in bitumen were simultaneously enhanced. Compared with SMB, the introduction of LDHs and organic LDHs (OLDHs) could ameliorate the high-temperature properties of SMB, and the thermostability of SBS in bitumen at a high temperature was also distinctly improved, especially OLDHs. After aging, due to the oxidation of molecular bitumen and the degradation of molecular SBS, SMB became hardened and brittle, and the rheological properties were significantly deteriorated, which had serious impacts on the performance of SMB. LDHs can mitigate the detriment of aging to bitumen and SBS, and the deterioration of the rheological properties of SMB is obviously alleviated. As a result of the better dispersibility and storage stability, OLDHs exerted superior reinforcement of the anti-aging ability of SMB. Full article
(This article belongs to the Section Construction and Building Materials)
Article
Exploring the Early Stages of the Amyloid Aβ(1–42) Peptide Aggregation Process: An NMR Study
Pharmaceuticals 2021, 14(8), 732; https://doi.org/10.3390/ph14080732 (registering DOI) - 27 Jul 2021
Abstract
Alzheimer’s disease (AD) is a neurodegenerative pathology characterized by the presence of neurofibrillary tangles and amyloid plaques, the latter mainly composed of Aβ(1–40) and Aβ(1–42) peptides. The control of the Aβ aggregation process as a therapeutic strategy for AD has prompted the interest [...] Read more.
Alzheimer’s disease (AD) is a neurodegenerative pathology characterized by the presence of neurofibrillary tangles and amyloid plaques, the latter mainly composed of Aβ(1–40) and Aβ(1–42) peptides. The control of the Aβ aggregation process as a therapeutic strategy for AD has prompted the interest to investigate the conformation of the Aβ peptides, taking advantage of computational and experimental techniques. Mixtures composed of systematically different proportions of HFIP and water have been used to monitor, by NMR, the conformational transition of the Aβ(1–42) from soluble α-helical structure to β-sheet aggregates. In the previous studies, 50/50 HFIP/water proportion emerged as the solution condition where the first evident Aβ(1–42) conformational changes occur. In the hypothesis that this solvent reproduces the best condition to catch transitional helical-β-sheet Aβ(1–42) conformations, in this study, we report an extensive NMR conformational analysis of Aβ(1–42) in 50/50 HFIP/water v/v. Aβ(1–42) structure was solved by us, giving evidence that the evolution of Aβ(1–42) peptide from helical to the β-sheet may follow unexpected routes. Molecular dynamics simulations confirm that the structural model we calculated represents a starting condition for amyloid fibrils formation. Full article
(This article belongs to the Special Issue High Field NMR and Ultra-High Field NMR in Medicinal Chemistry)
Review
Phytochemicals in Cancer Immune Checkpoint Inhibitor Therapy
Biomolecules 2021, 11(8), 1107; https://doi.org/10.3390/biom11081107 (registering DOI) - 27 Jul 2021
Abstract
The interaction of immune checkpoint molecules in the tumor microenvironment reduces the anti-tumor immune response by suppressing the recognition of T cells to tumor cells. Immune checkpoint inhibitor (ICI) therapy is emerging as a promising therapeutic option for cancer treatment. However, modulating the [...] Read more.
The interaction of immune checkpoint molecules in the tumor microenvironment reduces the anti-tumor immune response by suppressing the recognition of T cells to tumor cells. Immune checkpoint inhibitor (ICI) therapy is emerging as a promising therapeutic option for cancer treatment. However, modulating the immune system with ICIs still faces obstacles with severe immunogenic side effects and a lack of response against many cancer types. Plant-derived natural compounds offer regulation on various signaling cascades and have been applied for the treatment of multiple diseases, including cancer. Accumulated evidence provides the possibility of efficacy of phytochemicals in combinational with other therapeutic agents of ICIs, effectively modulating immune checkpoint-related signaling molecules. Recently, several phytochemicals have been reported to show the modulatory effects of immune checkpoints in various cancers in in vivo or in vitro models. This review summarizes druggable immune checkpoints and their regulatory factors. In addition, phytochemicals that are capable of suppressing PD-1/PD-L1 binding, the best-studied target of ICI therapy, were comprehensively summarized and classified according to chemical structure subgroups. It may help extend further research on phytochemicals as candidates of combinational adjuvants. Future clinical trials may validate the synergetic effects of preclinically investigated phytochemicals with ICI therapy. Full article
(This article belongs to the Section Molecular Medicine)
Article
Low-Molecular-Weight Fucoidan as Complementary Therapy of Fluoropyrimidine-Based Chemotherapy in Colorectal Cancer
Int. J. Mol. Sci. 2021, 22(15), 8041; https://doi.org/10.3390/ijms22158041 (registering DOI) - 27 Jul 2021
Abstract
This study investigated the roles of low-molecular-weight fucoidan (LMWF) in enhancing the anti-cancer effects of fluoropyrimidine-based chemotherapy. HCT116 and Caco-2 cells were treated with LMWF and 5-FU. Cell viability, cell cycle, apoptosis, and migration were analyzed in both cell types. Potential mechanisms underlying [...] Read more.
This study investigated the roles of low-molecular-weight fucoidan (LMWF) in enhancing the anti-cancer effects of fluoropyrimidine-based chemotherapy. HCT116 and Caco-2 cells were treated with LMWF and 5-FU. Cell viability, cell cycle, apoptosis, and migration were analyzed in both cell types. Potential mechanisms underlying how LMWF enhances the anti-cancer effects of fluoropyrimidine-based chemotherapy were also explored. The cell viability of HCT116 and Caco-2 cells was significantly reduced after treatment with a LMWF-–5FU combination. In HCT116 cells, LMWF enhanced the suppressive effects of 5-FU on cell viability through the 1) induction of cell cycle arrest in the S phase and 2) late apoptosis mediated by the Jun-N-terminal kinase (JNK) signaling pathway. In Caco-2 cells, LMWF enhanced the suppressive effects of 5-FU on cell viability through both the c-mesenchymal–epithelial transition (MET)/Kirsten rat sarcoma virus (KRAS)/extracellular signal-regulated kinase (ERK) and the c-MET/phosphatidyl-inositol 3-kinases (PI3K)/protein kinase B (AKT) signaling pathways. Moreover, LMWF enhanced the suppressive effects of 5-FU on tumor cell migration through the c-MET/matrix metalloproteinase (MMP)-2 signaling pathway in both HCT116 and Caco-2 cells. Our results demonstrated that LMWF is a potential complementary therapy for enhancing the efficacies of fluoropyrimidine-based chemotherapy in colorectal cancers (CRCs) with the wild-type or mutated KRAS gene through different mechanisms. However, in vivo studies and in clinical trials are required in order to validate the results of the present study. Full article
Article
The WL_PCR: A Planning for Ground-to-Pole Transition of Wheeled-Legged Pole-Climbing Robots
Robotics 2021, 10(3), 96; https://doi.org/10.3390/robotics10030096 (registering DOI) - 27 Jul 2021
Abstract
Hybrid mobile robots with two motion modes of a wheeled vehicle and truss structure with the ability to climb poles have significant flexibility. The motion planning of this kind of robot on a pole has been widely studied, but few studies have focused [...] Read more.
Hybrid mobile robots with two motion modes of a wheeled vehicle and truss structure with the ability to climb poles have significant flexibility. The motion planning of this kind of robot on a pole has been widely studied, but few studies have focused on the transition of the robot from the ground to the pole. In this study, a locomotion strategy of wheeled-legged pole-climbing robots (the WL_PCR) is proposed to solve the problem of ground-to-pole transition. By analyzing the force of static and dynamic process in the ground-to-pole transition, the condition of torque provided by the gripper and moving joint is proposed. The mathematical expression of Centre of Mass (CoM) of the wheeled-legged pole-climbing robots is utilized, and the conditions for the robot to smoothly transition from the ground to the vertical pole are proposed. Finally, the feasibility of this method is proved by the simulation and experimentation of a locomotion strategy on wheeled-legged pole-climbing robots. Full article
(This article belongs to the Topic Motion Planning and Control for Robotics)
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Article
Microstructure and Mechanical Properties of Al-Mg-Si Similar Alloy Laminates Produced by Accumulative Roll Bonding
Materials 2021, 14(15), 4200; https://doi.org/10.3390/ma14154200 (registering DOI) - 27 Jul 2021
Abstract
As the applications of heterogeneous materials expand, aluminum laminates of similar materials have attracted much attention due to their greater bonding strength and easier recycling. In this work, an alloy design strategy was developed based on accumulative roll bonding (ARB) to produce laminates [...] Read more.
As the applications of heterogeneous materials expand, aluminum laminates of similar materials have attracted much attention due to their greater bonding strength and easier recycling. In this work, an alloy design strategy was developed based on accumulative roll bonding (ARB) to produce laminates from similar materials. Twin roll casting (TRC) sheets of the same composition but different cooling rates were used as the starting materials, and they were roll bonded up to three cycles at varying temperatures. EBSD showed that the two TRC sheets deformed in distinct ways during ARB processes at 300°C. Major recrystallizations were significant after the first cycle on the thin sheet and after the third cycle on the thick sheet. The sheets were subject to subsequent aging for better mechanical properties. TEM observations showed that the size and distribution of nano-precipitations were different between the two sheet sides. These nano-precipitations were found to significantly promote precipitation strengthening, and such a promotive effect was referred to as hetero-deformation induced (HDI) strengthening. Our work provides a new promising method to prepare laminated heterogeneous materials with similar alloy TRC sheets. Full article
(This article belongs to the Topic Modern Technologies and Manufacturing Systems)
Proceedings
Coffee in the Workplace: A Social Break or a Performance Enhancer?
Med. Sci. Forum 2021, 5(1), 44; https://doi.org/10.3390/msf2021005044 (registering DOI) - 27 Jul 2021
Abstract
Coffee is a socially rooted drink with pharmacological properties. It is embedded in different everyday rituals, including ‘coffee breaks’ during working hours. This paper analyzes the role of coffee at workplace. Focusing on three professional areas associated with high pressure and responsive demands, [...] Read more.
Coffee is a socially rooted drink with pharmacological properties. It is embedded in different everyday rituals, including ‘coffee breaks’ during working hours. This paper analyzes the role of coffee at workplace. Focusing on three professional areas associated with high pressure and responsive demands, we explore the social expression of coffee use at work, and how it is mobilized as a tool for managing sleepiness, fatigue, stress, and concentration problems, amongst other work-related issues. Full article
Article
Benefits and Trade-Offs of Tillage Management in China: A Meta-Analysis
Agronomy 2021, 11(8), 1495; https://doi.org/10.3390/agronomy11081495 (registering DOI) - 27 Jul 2021
Abstract
In China, deep tillage (DT; to >20 cm soil depth) has increased crop yields by improving soil properties, while no-tillage (NT) has been recommended to reduce the labor and machinery costs. Local farmers are willing to adopted rotary tillage (RT; harrowing to 10–15 [...] Read more.
In China, deep tillage (DT; to >20 cm soil depth) has increased crop yields by improving soil properties, while no-tillage (NT) has been recommended to reduce the labor and machinery costs. Local farmers are willing to adopted rotary tillage (RT; harrowing to 10–15 cm depth) for easy management. However, the effects of these tillage management methods on agronomic productivity, greenhouse gas (GHG) emissions, soil organic carbon (SOC) sequestration, and economic return have not been quantified systematically, and their effectiveness remains in question. Here, we present a meta-analysis of the effects of these methods using 665 paired measurements from 144 peer-reviewed studies. The results indicated that DT significantly increased crop yields by 7.5% relative to RT, and even greater increases were observed in regions with low temperatures and with a wheat cropping system. In contrast, NT resulted in a yield reduction of 3.7% relative to RT, however, controlling for the appropriate temperature and long extension duration (>15 yr) could reduce yield losses and even increase the yield. Both DT and NT significantly enhanced SOC sequestration relative to RT. Adoption of DT would lead to both higher total GHG emissions (N2O and CH4) and increased energy costs, while NT reduced GHG emissions. DT management exhibited a positive net profit for all cropping systems; NT decreased the net profit for rice and wheat but increased the profit for maize. Our study highlighted the agronomic, environmental, and economic benefits and trade-offs for the different tillage methods and should enable investors and policymakers to ensure the best tillage management decisions are made depending on the location-specific conditions. Full article
(This article belongs to the Section Farming Sustainability)

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