bluuebunny/crossref_metadata_2025 huggingface dataset:
Proteomic Analysis Unveils Expressional Changes in Cytoskeleton- and Synaptic Plasticity-Associated Proteins in Rat Brain Six Months after Withdrawal from Morphine
Authors: Drastichova Zdenka , Hejnova Lucie , Moravcova Radka , Novotny Jiri
Published: July 2021

Drug withdrawal is associated with abstinence symptoms including deficits in cognitive functions that may persist even after prolonged discontinuation of drug intake. Cognitive deficits are, at least partially, caused by alterations in synaptic plasticity but the precise molecular mechanisms have not yet been fully identified. In the present study, changes in proteomic and phosphoproteomic profiles of selected brain regions (cortex, hippocampus, striatum, and cerebellum) from rats abstaining for six months after cessation of chronic treatment with morphine were determined by label-free quantitative (LFQ) proteomic analysis. Interestingly, prolonged morphine withdrawal was found to be associated especially with alterations in protein phosphorylation and to a lesser extent in protein expression. Gene ontology (GO) term analysis revealed enrichment in biological processes related to synaptic plasticity, cytoskeleton organization, and GTPase activity. More specifically, significant changes were observed in proteins localized in synaptic vesicles (e.g., synapsin-1, SV2a, Rab3a), in the active zone of the presynaptic nerve terminal (e.g., Bassoon, Piccolo, Rims1), and in the postsynaptic density (e.g., cadherin 13, catenins, Arhgap35, Shank3, Arhgef7). Other differentially phosphorylated proteins were associated with microtubule dynamics (microtubule-associated proteins, Tppp, collapsin response mediator proteins) and the actin–spectrin network (e.g., spectrins, adducins, band 4.1-like protein 1). Taken together, a six-month morphine withdrawal was manifested by significant alterations in the phosphorylation of synaptic proteins. The altered phosphorylation patterns modulating the function of synaptic proteins may contribute to long-term neuroadaptations induced by drug use and withdrawal.
Outcomes of Migraine and Tension-Type Headache in Children and Adolescents
Authors: Genizi Jacob , Hendler-Sade Ayellet , Segal Idan , Bamberger Ellen , Srugo Isaac , Kerem Nogah C.
Published: July 2021

The aim of our study was to evaluate the long-term outcomes of pediatric migraine and TTH in a clinical setting. We conducted a cohort study. Pediatric patients who visited the pediatric neurology clinic due to diagnoses of migraine or TTH were contacted by phone 8–10 years after their initial diagnosis and interviewed about their outcomes. Of 147 children, we were able to reach 120 (81%) patients. Of these 120 patients, 59 were seen initially due to migraine and 61 due to TTH. For the migraine patients, headaches improved in 48 (81.4%) and worsened in four (6.8%). Regarding diagnosis at follow-up, 59% still had migraine, 17% had TTH, and 23% were headache-free. Aura and photophobia were significantly associated with persistence of a migraine diagnosis. For the TTH patients, headaches improved in 49 (81.7%) and worsened in nine (15.0%). Regarding diagnosis at follow-up, 36.7% still had TTH, 18.3% had migraine, and 45% were headache-free. Of the patients with TTH, 36.7% retained their initial diagnosis compared to 59.3% among the migraine patients. Most pediatric patients presenting with migraine or TTH will experience a favorable outcome over 10 years, with TTH patients having twice the chance of complete resolution.
Lignans from Bursera fagaroides: Chemistry, Pharmacological Effects and Molecular Mechanism. A Current Review
Authors: Antúnez-Mojica Mayra , Romero-Estrada Antonio , Hurtado-Díaz Israel , Miranda-Molina Alfonso , Alvarez Laura
Published: July 2021

Bursera fagaroides is a medicinal tree endemic to México, it belongs to the Burseraceae family and has proven antitumor activity. Modern research, performed principally with the bark extracts, have indicated that lignans are the main active constituents of B. fagaroides, with a high content of aryltetralin, aryldihydronaphtalene, dibenzylbutirolactone, and dibenzylbutane-type lignans as the constituents of the active extracts. In general, lignans from B. fagaroides exhibited potent anti-cancer activity, although antitumor, anti-bacterial, anti-protozoal, anti-inflammatory, and anti-viral properties have also been described. This review covers literature-reported lignans from B. fagaroides, chemical structures, nomenclature, chromatographic techniques of isolation, characterization strategies, and highlights the anti-cancer molecular mechanisms of lignans. Evaluation of the anticancer function of lignans has been extensively investigated since the cytotoxic in vitro results and in vivo assays in mice and zebrafish models to the tubulin molecular recognition by NMR. Also, we discuss the future direction for studying this important plant species and its lignan metabolites.
Mitogenomics, Phylogeny and Morphology Reveal Ophiocordyceps pingbianensis Sp. Nov., an Entomopathogenic Fungus from China
Authors: Chen Siqi , Wang Yuanbing , Zhu Kongfu , Yu Hong
Published: July 2021

The new entomopathogenic fungus Ophiocordyceps pingbianensis, collected from Southeast China, was described by mitogenomic, morphological, and phylogenetic evidence. The systematic position of O. pingbianensis was determined by phylogenetic analyses based on six nuclear gene (ITS, tef1-α, nrSSU, nrLSU, rpb1 and rpb2) and 14 mitochondrial protein-coding gene (PCGs) (cox1, cox2, cox3, atp6, atp8, atp9, cob, nad1, nad2, nad3, nad4, nad5, nad6 and nad4L) data. Phylogenetic analyses reveal that O. pingbianensis was belonged to the Hirsutella nodulosa clade in the genus Ophiocordyceps of Ophiocordycipiaceae. This fungus exhibits distinctive characteristics which differed from other related Ophiocordyceps species with slender and geminate stromata, monophialidic conidiogenous cells with an inflated awl-shaped base, a twisty and warty phialide neck and a fusiform or oval conidia, as well as being found on a tiger beetle of Coleoptera buried in moss at the cave. The complete mitochondrial genome of O. pingbianensis was a circular DNA molecule 80,359 bp in length, containing 15 PCGs, 24 open reading frames genes (ORFs), 25 transfer RNA genes (tRNAs) and 27 introns. Ophiocordyceps pingbianensis, containing 27 introns, has the second largest mitogenome in Ophiocordycipiaceae and was next to O. sinensis. To our knowledge, this is the first report of the mitogenome from a new entomopathogenic fungus, and thus provides an important foundation for future studies on taxonomy, genetics and evolutionary biology of Ophiocordycipiaceae.
Metabolome Profiling of Eight Chinese Yam (Dioscorea polystachya Turcz.) Varieties Reveals Metabolite Diversity and Variety Specific Uses
Authors: Zeng Xiaoxuan , Liu Dahui , Huang Luqi
Published: July 2021

The Chinese yam (Dioscorea polystachya Turcz.) is an underutilized orphan tuber crop. However, in China it has been used in traditional medicine and food for centuries due to the presence of high starch, protein, fiber, and biologically active compounds. Knowledge on the metabolomic profiles of Chinese yam varieties is needed to explore the underutilized metabolites and variety specific uses. Here, the metabolome of eight Chinese yam varieties that are cultivated in different Chinese regions was profiled. A total of 431 metabolites belonging to different biochemical classes was detected. The majority of detected metabolites were classified as amino acids and derivatives. The different yam varieties offer unique uses; e.g., Hebei Ma Yam, Henan Huai Yam, and Henan Wild Yam were the most metabolically enriched and suitable as food and medicine. Yams from Hubei region had comparable nutritional profiles, which is most probably due to their geographical origin. Specifically, Henan Wild Yam had the highest concentrations of diosgenin, vitamins, and polysaccharides. Overall, this study presents a metabolome reference for D. polystachya varieties.
Quantitative Evaluation of the Movement Distance of Deep Fascia and Change of Muscle Shape Related to Chain Response in Fascia Tissue of Lower Limb
Authors: Sugawara Kazuyuki , Aoki Mitsuhiro , Yamane Masahiro
Published: July 2021

By using ultrasonography, we measured the longitudinal movement distance of the deep fascia (LMDDF), change of the pennation angle (PA) and muscle thickness (MT) in both the tensor fasciae latae muscle (TFL) and the gluteus medius muscle (G-Med) during passive movement of the toes/ankle joints. 21 right lower limbs of 21 healthy males were evaluated in this study. We measured the LMDDF of the TFL and G-Med by measuring distance between the designated landmark on skin and the intersection of the major deep-fascia (D-fascia) and the fascial bundle. We also measured change of the PA and MT of both muscles. Additionally, we also measured the reliability of the measurement and the measurement error. The measurement was performed during three manual positions on the toes/ankle; manual holding of the toes and ankle joint in neutral, toes flexion and ankle plantar flexion/inversion position, toes extension and ankle extension/valgus position. The existence of muscle contraction of both the muscles during passive motion was monitored by active surface electrodes. This study confirmed mobility of the D-fascia in which the TFL’s D-fascia moves and change of muscle shape in the distal direction during no muscle contraction due to passive movement. This fact suggests the possibility that passive tension on fascia tissue of the ankle extends to the proximal part of the limb, i.e., to the D-fascia of the TFL.
‘Whole Organism’, Systems Biology, and Top-Down Criteria for Evaluating Scenarios for the Origin of Life
Authors: Brunk Clifford F. , Marshall Charles R.
Published: July 2021

While most advances in the study of the origin of life on Earth (OoLoE) are piecemeal, tested against the laws of chemistry and physics, ultimately the goal is to develop an overall scenario for life’s origin(s). However, the dimensionality of non-equilibrium chemical systems, from the range of possible boundary conditions and chemical interactions, renders the application of chemical and physical laws difficult. Here we outline a set of simple criteria for evaluating OoLoE scenarios. These include the need for containment, steady energy and material flows, and structured spatial heterogeneity from the outset. The Principle of Continuity, the fact that all life today was derived from first life, suggests favoring scenarios with fewer non-analog (not seen in life today) to analog (seen in life today) transitions in the inferred first biochemical pathways. Top-down data also indicate that a complex metabolism predated ribozymes and enzymes, and that full cellular autonomy and motility occurred post-LUCA. Using these criteria, we find the alkaline hydrothermal vent microchamber complex scenario with a late evolving exploitation of the natural occurring pH (or Na+ gradient) by ATP synthase the most compelling. However, there are as yet so many unknowns, we also advocate for the continued development of as many plausible scenarios as possible.
In Vitro Measurements of Cellular Forces and their Importance in the Lung—From the Sub- to the Multicellular Scale
Authors: Kolb Peter , Schundner Annika , Frick Manfred , Gottschalk Kay-E.
Published: July 2021

Throughout life, the body is subjected to various mechanical forces on the organ, tissue, and cellular level. Mechanical stimuli are essential for organ development and function. One organ whose function depends on the tightly connected interplay between mechanical cell properties, biochemical signaling, and external forces is the lung. However, altered mechanical properties or excessive mechanical forces can also drive the onset and progression of severe pulmonary diseases. Characterizing the mechanical properties and forces that affect cell and tissue function is therefore necessary for understanding physiological and pathophysiological mechanisms. In recent years, multiple methods have been developed for cellular force measurements at multiple length scales, from subcellular forces to measuring the collective behavior of heterogeneous cellular networks. In this short review, we give a brief overview of the mechanical forces at play on the cellular level in the lung. We then focus on the technological aspects of measuring cellular forces at many length scales. We describe tools with a subcellular resolution and elaborate measurement techniques for collective multicellular units. Many of the technologies described are by no means restricted to lung research and have already been applied successfully to cells from various other tissues. However, integrating the knowledge gained from these multi-scale measurements in a unifying framework is still a major future challenge.
The Influence of Mechanical Deformations on Surface Force Measurements
Authors: Lhermerout Romain
Published: July 2021

Surface Force Balance (SFB) experiments have been performed in a dry atmosphere and across an ionic liquid, combining the analysis of surface interactions and deformations, and illustrate that the mechanical deformations of the surfaces have important consequences for the force measurements. First, we find that the variation of the contact radius with the force across the ionic liquid is well described only by the Derjaguin–Muller–Toporov (DMT) model, in contrast with the usual consideration that SFB experiments are always in the Johnson–Kendall–Roberts (JKR) regime. Secondly, we observe that mica does not only bend but can also experience a compression, of order 1nm with 7μm mica. We present a modified procedure to calibrate the mica thickness in a dry atmosphere, and we show that the structural forces measured across the ionic liquid cannot be described by the usual exponentially decaying harmonic oscillation, but should be considered as a convolution of the surface forces across the liquid and the mechanical response of the confining solids. The measured structural force profile is fitted with a heuristic formulation supposing that mica compression is dominant over liquid compression, and a scaling criterion is proposed to distinguish situations where the solid deformation is negligible or dominant.
Formation of ZrC–SiC Composites from the Molecular Scale through the Synthesis of Multielement Polymers
Authors: Bouzat Fabien , Lucas Romain , Leconte Yann , Foucaud Sylvie , Champavier Yves , Coelho Diogo Cristina , Babonneau Florence
Published: July 2021

In the field of non-oxide ceramic composites, and by using the polymer-derived ceramic route, understanding the relationship between the thermal behaviour of the preceramic polymers and their structure, leading to the mechanisms involved, is crucial. To investigate the role of Zr on the fabrication of ZrC–SiC composites, linear or hyperbranched polycarbosilanes and polyzirconocarbosilanes were synthesised through either “click-chemistry” or hydrosilylation reactions. Then, the thermal behaviours of these polymeric structures were considered, notably to understand the impact of Zr on the thermal path going to the composites. The inorganic materials were characterised by thermogravimetry-mass spectrometry (TG-MS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). To link the macromolecular structure to the organisation involved during the ceramisation process, eight temperature domains were highlighted on the TG analyses, and a four-step mechanism was proposed for the polymers synthesised by a hydrosilylation reaction, as they displayed better ceramic yields. Globally, the introduction of Zr in the polymer had several effects on the temperature fragmentation mechanisms of the organometallic polymeric structures: (i) instead of stepwise mass losses, continuous fragment release prevailed; (ii) the stability of preceramic polymers was impacted, with relatively good ceramic yields; (iii) it modulated the chemical composition of the generated composites as it led, inter alia, to the consumption of free carbon.
Strength Analysis and Stress-Strain Deformation Behavior of 3 mol% Y-TZP and 21 wt.% Al2O3-3 mol% Y-TZP
Authors: Vladislavova Liliya , Smolorz Tomasz , Orlovskaya Nina , Lugovy Mykola , Reece Michael J. , Kӧbel Stefan , Kopia Agnieszka , Makowska Malgorzata , Graule Thomas , Blugan Gurdial
Published: July 2021

The mechanical behavior of 3 mol% Y2O3-ZrO2 ceramic and 21 wt.% Al2O3-3 mol% Y2O3-ZrO2 ceramic composite with submicron grain size was studied. Mechanical properties, such as hardness, Young’s modulus, four-point bending strength, and fracture toughness of both materials were measured. Linear stress-strain deformation behavior of both 3 mol% Y2O3-ZrO2 and 21 wt.% Al2O3-3 mol% Y2O3-ZrO2 was observed in flexure, both at room temperature and at 400 °C. A small deviation from linear elastic deformation was detected in 21 wt.% Al2O3-3 mol% Y2O3-ZrO2 ceramic composite when loaded above a stress of 1500 MPa. Therefore, it was concluded that only elastic deformation occurred at low stresses upon loading, which exclude the presence of domain switching in zirconia upon bending under the loading conditions of this study.
A Review of Conductive Carbon Materials for 3D Printing: Materials, Technologies, Properties, and Applications
Authors: Zheng Yanling , Huang Xu , Chen Jialiang , Wu Kechen , Wang Jianlei , Zhang Xu
Published: July 2021

Carbon material is widely used and has good electrical and thermal conductivity. It is often used as a filler to endow insulating polymer with electrical and thermal conductivity. Three-dimensional printing technology is an advance in modeling and manufacturing technology. From the forming principle, it offers a new production principle of layered manufacturing and layer by layer stacking formation, which fundamentally simplifies the production process and makes large-scale personalized production possible. Conductive carbon materials combined with 3D printing technology have a variety of potential applications, such as multi-shape sensors, wearable devices, supercapacitors, and so on. In this review, carbon black, carbon nanotubes, carbon fiber, graphene, and other common conductive carbon materials are briefly introduced. The working principle, advantages and disadvantages of common 3D printing technology are reviewed. The research situation of 3D printable conductive carbon materials in recent years is further summarized, and the performance characteristics and application prospects of these conductive carbon materials are also discussed. Finally, the potential applications of 3D printable conductive carbon materials are concluded, and the future development direction of 3D printable conductive carbon materials has also been prospected.
Combination of Au-Ag Plasmonic Nanoparticles of Varied Compositions with Carbon Nitride for Enhanced Photocatalytic Degradation of Ibuprofen under Visible Light
Authors: Jiménez-Salcedo Marta , Monge Miguel , Tena María Teresa
Published: July 2021

Au-Ag/g-C3N4 nanohybrids 2–3 were synthesized by the one-pot self-reduction of the organometallic precursor [Au2Ag2(C6F5)4(OEt2)2]n in the presence of graphitic carbon nitride (g-C3N4), leading to two populations of alloyed Au-Ag nanoparticles (NPs) of different size and composition on the surface of g-C3N4, i.e., Ag-enriched Au-Ag NPs of smaller size and Au-enriched Au-Ag NPs of larger size. The combination of these two types of plasmonic NPs with g-C3N4 semiconductor displays enhanced photocatalytic properties towards the degradation of ibuprofen under visible light by the increased charge carrier separation provided by the inclusion of the plasmonic NPs on g-C3N4.
The Role of La2O3 in Enhancement the Radiation Shielding Efficiency of the Tellurite Glasses: Monte-Carlo Simulation and Theoretical Study
Authors: Almuqrin Aljawhara H. , Hanfi Mohamed , Mahmoud K. G. , Sayyed M. I. , Al-Ghamdi Hanan , Aloraini Dalal Abdullah
Published: July 2021

The radiation shielding competence was examined for a binary glass system xLa2O3 + (1 − x) TeO2 where x = 5, 7, 10, 15, and 20 mol% using MCNP-5 code. The linear attenuation coefficients (LACs) of the glasses were evaluated, and it was found that LT20 glass has the greatest LAC, while LT5 had the least LAC. The transmission factor (TF) of the glasses was evaluated against thicknesses at various selected energies and was observed to greatly decrease with increasing thickness; for example, at 1.332 MeV, the TF of the LT5 glass decreased from 0.76 to 0.25 as the thickness increased from 1 to 5 cm. The equivalent atomic number (Zeq) of the glasses gradually increased with increasing photon energy above 0.1 MeV, with the maximum values observed at around 1 MeV. The buildup factors were determined to evaluate the accumulation of photon flux, and it was found that the maximum values for both can be seen at around 0.8 MeV. This research concluded that LT20 has the greatest potential in radiation shielding applications out of the investigated glasses due to the glass having the most desirable parameters.
Prediction of the Compressive Strength of Recycled Aggregate Concrete Based on Artificial Neural Network
Authors: Bu Liangtao , Du Guoqiang , Hou Qi
Published: July 2021

Recycled aggregate concrete (RAC), due to its high porosity and the residual cement and mortar on its surface, exhibits weaker strength than common concrete. To guarantee the safe use of RAC, a compressive strength prediction model based on artificial neural network (ANN) was built in this paper, which can be applied to predict the RAC compressive strength for 28 days. A data set containing 88 data points was obtained by relative tests with different mix proportion designs. The data set was used to develop an ANN, whose optimal structure was determined using the trial-and-error method by taking cement content (C), sand content (S), natural coarse aggregate content (NCA), recycled coarse aggregate content (RCA), water content (W), water–colloid ratio (WCR), sand content rate (SR), and replacement rate of recycled aggregate (RRCA) as input parameters. On the basis of different numbers of hidden layers, numbers of hidden layer neurons, and transfer functions, a total of 840 different back propagation neural network (BPNN) models were developed using MATLAB software, which were then sorted according to the correlation coefficient R2. In addition, the optimal BPNN structure was finally determined to be 8–12–8–1. For the training set, the correlation coefficient R2 = 0.97233 and RMSE = 2.01, and for the testing set, the correlation coefficient R2 = 0.96650 and RMSE = 2.42. The model prediction deviations of the two were both less than 15%, and the results show that the ANN achieved pretty accurate prediction on the compressive strength of RAC. Finally, a sensitivity analysis was carried out, through which the impact of the input parameters on the predicted compressive strength of the RAC was obtained.
Selective Doping in Silicon Carbide Power Devices
Authors: Roccaforte Fabrizio , Fiorenza Patrick , Vivona Marilena , Greco Giuseppe , Giannazzo Filippo
Published: July 2021

Silicon carbide (SiC) is the most mature wide band-gap semiconductor and is currently employed for the fabrication of high-efficiency power electronic devices, such as diodes and transistors. In this context, selective doping is one of the key processes needed for the fabrication of these devices. This paper concisely reviews the main selective doping techniques for SiC power devices technology. In particular, due to the low diffusivity of the main impurities in SiC, ion implantation is the method of choice to achieve selective doping of the material. Hence, most of this work is dedicated to illustrating the main features of n-type and p-type ion-implantation doping of SiC and discussing the related issues. As an example, one of the main features of implantation doping is the need for post-implantation annealing processes at high temperatures (above 1500 °C) for electrical activation, thus having a notable morphological and structural impact on the material and, hence, on some device parameters. In this respect, some specific examples elucidating the relevant implications on devices’ performances are reported in the paper. Finally, a short overview of recently developed non-conventional doping and annealing techniques is also provided, although these techniques are still far from being applied in large-scale devices’ manufacturing.
The Influence of the Hydrophobic Polymeric Coating on 5-ASA Release from the Bipolymeric Milibeads with Amidated Pectin
Authors: Wójcik-Pastuszka Dorota , Barczyszyn Kinga , Musiał Witold
Published: July 2021

The industrial polymeric carriers for peroral mesalazine application exploit, i.a., cellulose or polyacrylic acid derivatives, polyvinylpyrrolidone, and modified starch. Pectins, as natural polymers, are interesting materials in pharmaceutical applications due to properties such as non-toxicity, biocompatibility, and biodegradability. The aim of the study was the evaluation of the release of the drug from coated pectin beads doped with synthetic polymers as drug carriers to the colon, as well as interactions between ingredients. The drug release was carried out using basket apparatus. The amount of 5-ASA (5-aminosalicylic acid, mesalazine) released to the pH = 7.4 buffer with pectinase was measured at selected time intervals using UV-Vis spectroscopy. The zero-, first-, and second-order kinetics, as well as Higuchi, Korsmeyer–Peppas, and Hixon–Crowell equations, were used to analyze the release pattern. The interactions between beads components were investigated employing FTIR spectrophotometry and DSC study. The dissolution of the drug was divided into two parts. It was found that the release of 5-ASA followed mainly the Higuchi equation. The mass transport in the first stage of the release followed a non-Fickian model and the parameter n was in the range of 0.74 ± 0.2–0.99 ± 0.2. The formulation doped with PA (polyacrylic acid) was the most appropriate and capable of overcoming the variable conditions of the gastrointestinal tract.
Analysis of Flexural Vibrations of a Piezoelectric Semiconductor Nanoplate Driven by a Time-Harmonic Force
Authors: Li Mengen , Zhang Qiaoyun , Wang Bingbing , Zhao Minghao
Published: July 2021

The performance of devices fabricated from piezoelectric semiconductors, such as sensors and actuators in microelectromechanical systems, is superior; furthermore, plate structures are the core components of these smart devices. It is thus important to analyze the electromechanical coupling properties of piezoelectric semiconductor nanoplates. We established a nanoplate model for the piezoelectric semiconductor plate structure by extending the first-order shear deformation theory. The flexural vibrations of nanoplates subjected to a transversely time-harmonic force were investigated. The vibrational modes and natural frequencies were obtained by using the matrix eigenvalue solver in COMSOL Multiphysics 5.3a, and the convergence analysis was carried out to guarantee accurate results. In numerical cases, the tuning effect of the initial electron concentration on mechanics and electric properties is deeply discussed. The numerical results show that the initial electron concentration greatly affects the natural frequency and electromechanical fields of piezoelectric semiconductors, and a high initial electron concentration can reduce the electromechanical fields and the stiffness of piezoelectric semiconductors due to the electron screening effect. We analyzed the flexural vibration of typical piezoelectric semiconductor plate structures, which provide theoretical guidance for the development of new piezotronic devices.
Low-Diffusion Fricke Gel Dosimeters with Core-Shell Structure Based on Spatial Confinement
Authors: Zhang Wei , Wang Kaikai , Zeng Yufeng , Hu Xiaodan , Zhang Xiaohong , Chang Shuquan , Zhang Haiqian
Published: July 2021

The diffusion of ferric ions is an important challenge to limit the application of Fricke gel dosimeters in accurate three-dimensional dose verification of modern radiotherapy. In this work, low-diffusion Fricke gel dosimeters, with a core-shell structure based on spatial confinement, were constructed by utilizing microdroplet ultrarapid freezing and coating technology. Polydimethylsiloxane (PDMS), with its excellent hydrophobicity, was coated on the surface of the pellets. The concentration gradient of the ferric ion was realized through shielding half of a Co-60 photon beam field size, and ion diffusion was measured by both ultraviolet-visible spectrophotometry and magnetic resonance imaging. No diffusion occurred between the core-shell pellets, even at 96 h after irradiation, and the diffusion length at the irradiation boundary was limited to the diameter (2–3 mm) of the pellets. Furthermore, Monte Carlo calculations were conducted to study dosimetric properties of the core-shell dosimeter, which indicated that a PDMS shell hardly affected the performance of the dosimeter.
Bonding Interface and Repairability of 3D-Printed Intraoral Splints: Shear Bond Strength to Current Polymers, with and without Ageing
Authors: Kuscu Ebru , Klink Andrea , Spintzyk Sebastian , Kraemer Fernandez Pablo , Huettig Fabian
Published: July 2021

This in-vitro study investigates the bonding interfaces reached by the conditioning of a splint material additively manufactured by digital light processing (AM base) as well as the shear bond strength (SBS) of resins bonded to these surfaces (repair material). Therefore, the AM base was either stored in dry for 12 h or wet environment for 14 days to simulate ageing by intraoral wear. The dry and wet group was bonded after physical and/or chemical conditioning to cylinders made from polymethylmethacrylate or four novel polymers allowing splint modifications. Blasted and methylmethacrylate (MMA)-conditioned Polymethylmethacrylate (PMMA) bonded to PMMA acted as the gold standard. The surface profiles revealed highest differences of Ra towards the gold standard in AM base conditioned with other than MMA after sandblasting. The adhesively bonded repair materials of the wet AM base were further aged in wet environment for 14 days. The SBS of the gold standard (25.2 MPa and 25.6 MPa) was only reached by PMMA bonded to blasted and MMA-conditioned AM base after dry (22.7 MPa) and non-conditioned after wet storage (23 MPa). Four repair materials failed to reach the threshold of 5 MPa after dry storage and three after wet storage, respectively. Non-conditioned AM base revealed the highest risk for adhesive fractures when using other resins than PMMA.
Experimental Study on the Axial Tensile Properties of FRP Grid-Reinforced ECC Composites
Authors: Deng Langni , Lei Lizhen , Lai Shijin , Liao Ling , Zhou Zheng
Published: July 2021

The axial tensile properties of FRP mesh-reinforced ECC composites (TRE) were investigated experimentally under the consideration of four influencing factors: grid type, number of reinforcement layers, ECC matrix thickness, and sticky sand treatment on the grid surface. The test results showed that the axial stiffness and tensile strength of the composite were significantly increased, and the tensile properties were significantly improved under the effect of FRP grid reinforcement. Increasing the thickness of the ECC matrix can obviously improve the crack resistance of composites. The ultimate tensile strength of FRP lattice-reinforced ECC composites increased significantly with the increase in the number of lattice layers, but had no significant effect on the crack resistance. The tensile properties of CFRP grid-reinforced ECC composites were slightly better compared to BFRP grid-reinforced ECC composites. The crack resistance and ultimate tensile strength of the composites were slightly improved by impregnating the surface of the FRP grid with adhesive-bonded sand treatment. Based on the experimental data, the tensile stress–strain constitutive model of FRP grid-reinforced ECC composites is established. The calculation results show that the theoretical values of the model agree well with the experimental values. Therefore, it can be used to reflect the stress–strain change state of FRP lattice-reinforced ECC composites during axial tension.
Autologous Platelet Gel (APG): A Preliminary Evaluation of the Mechanical Properties after Activation with Autologous Thrombin and Calcium Chloride
Authors: Scarano Antonio , Bugea Calogero , Leo Lucia , Santos de Oliveira Pablo , Lorusso Felice
Published: July 2021

The tensional and mechanical behavior of regenerative components, grafts, and blood clots represent an essential condition for the success of bone regeneration protocols. Autologous platelet growth factors represent a useful protocol to enhance the soft and hard tissue healing in several fields of medicine and craniofacial surgery. Different protocols for blood concentrates with and without activation have been proposed in literature. The aim of the present study was to investigate in vitro the mechanical properties of autologous platelet gel (APG) with autologous thrombin and calcium chloride. Materials and Methods: A total of 20 APG samples were evaluated; 10 samples were activated by autologous thrombin and calcium chloride (Group I) and 10 samples were non-activated (Group II). The tensile strength and modulus of elasticity were calculated through a static loading test (Lloyd 30 K, Lloyd Instruments Ltd., Segensworth, UK). Results: Group I (activated) reported a tensile strength of 373.5 ± 14.3 MPa, while Group II showed a significantly lower value of 360.5 ± 16.3 MPa (p < 0.05). The Young’s modulus was 145.3 ± 10.4 MPa for Group I and 140.3 ± 15.3 MPa for Group II (p < 0.05). Conclusions: The effectiveness of the present in vitro simulation showed that the APG activation protocol is able to increase the mechanical characteristics of the blood derivates and could be clinically useful to enhance regenerative procedures.
Microstructural Characterization of Laser Weld of Hot-Stamped Al-Si Coated 22MnB5 and Modification of Weld Properties by Hybrid Welding
Authors: Šebestová Hana , Horník Petr , Mikmeková Šárka , Mrňa Libor , Doležal Pavel , Novotný Jan
Published: July 2021

The presence of Al-Si coating on 22MnB5 leads to the formation of large ferritic bands in the dominantly martensitic microstructure of butt laser welds. Rapid cooling of laser weld metal is responsible for insufficient diffusion of coating elements into the steel and incomplete homogenization of weld fusion zone. The Al-rich regions promote the formation of ferritic solid solution. Soft ferritic bands cause weld joint weakening. Laser welds reached only 64% of base metal’s ultimate tensile strength, and they always fractured in the fusion zone during the tensile tests. We implemented hybrid laser-TIG welding technology to reduce weld cooling rate by the addition of heat of the arc. The effect of arc current on weld microstructure and mechanical properties was investigated. Thanks to the slower cooling, the large ferritic bands were eliminated. The hybrid welds reached greater ultimate tensile strength compared to laser welds. The location of the fracture moved from the fusion zone to a tempered heat-affected zone characterized by a drop in microhardness. The minimum of microhardness was independent of heat input in this region.
Improved Biological Responses of Titanium Coating Using Laser-Aided Direct Metal Fabrication on SUS316L Stainless Steel
Authors: Kim Tae-In , Lee Se-Won , Jo Woo-Lam , Kim Yong-Sik , Kim Seung-Chan , Kwon Soon-Yong , Lim Young-Wook
Published: July 2021

Direct metal fabrication (DMF) coatings have the advantage of a more uniform porous structure and superior mechanical properties compared to coatings provided by other methods. We applied pure titanium metal powders to SUS316L stainless steel using laser-aided DMF coating technology with 3D printing. The purpose of this study was to determine the efficacy of this surface modification of stainless steel. The capacity of cells to adhere to DMF-coated SUS316L stainless steel was compared with machined SUS316L stainless steel in vitro and in vivo. Morphological in vitro response to human osteoblast cell lines was evaluated using scanning electron microscopy. Separate specimens were inserted into the medulla of distal femurs of rabbits for in vivo study. The distal femurs were harvested after 3 months, and were then subjected to push-out test and histomorphometrical analyses. The DMF group exhibited a distinct surface chemical composition, showing higher peaks of titanium compared to the machined stainless steel. The surface of the DMF group had a more distinct porous structure, which showed more extensive coverage with lamellipodia from osteoblasts than the machined surface. In the in vivo test, the DMF group showed better results than the machined group in the push-out test (3.39 vs. 1.35 MPa, respectively, p = 0.001). In the histomorphometric analyses, the mean bone-to-implant contact percentage of the DMF group was about 1.5 times greater than that of the machined group (65.4 ± 7.1% vs. 41.9 ± 5.6%, respectively; p < 0.001). The porous titanium coating on SUS316L stainless steel produced using DMF with 3D printing showed better surface characteristics and biomechanical properties than the machined SUS316L.
Correction: Pfeifer, D.; Ragulina, O. Adaptive Bernstein Copulas and Risk Management. Mathematics 2020, 8, 2221
Authors: Pfeifer Dietmar , Ragulina Olena
Published: July 2021

The authors wish to make the following corrections to this paper [1]:1 [...]
ICT Use and Successful Learning: The Role of the Stock of Human Capital
Authors: Gimenez Gregorio , Vargas-Montoya Luis
Published: July 2021

Previous empirical studies have found a weak nexus between the use of information and communication technologies (ICT) for learning and students’ outcomes. However, this literature has not considered the role that the countries’ stock of human capital can have in the successful use of ICT for learning. In this paper, we test empirically the existence of complementarities between human capital and technology adoption for learning. We carry out an empirical analysis with PISA data from a large-scale sample of 363,412 students enrolled in 13,215 schools in 48 countries. We estimate a hierarchical linear model (HLM) of three levels: students, schools, and countries. Our results strongly support the evidence of a positive externality of the stock of human capital on ICT use for learning. When we consider the moderator-effect of the stock of human capital, we find that the negative outcome of ICT use on students’ outcomes in mathematics, reading and science turns positive (greater and more positive the higher the stocks of human capital are). The greater the stock of human capital an economy has, the more benefits it can get from investments in ICT for learning.
Potential-Growth Indicators Revisited: Higher Generality and Wider Merit of Indication
Authors: Logofet Dmitrii , Razzhevaikin Valerii
Published: July 2021

The notion of a potential-growth indicator came to being in the field of matrix population models long ago, almost simultaneously with the pioneering Leslie model for age-structured population dynamics, although the term has been given and the theory developed only in recent years. The indicator represents an explicit function, R(L), of matrix L elements and indicates the position of the spectral radius of L relative to 1 on the real axis, thus signifying the population growth, or decline, or stabilization. Some indicators turned out to be useful in theoretical layouts and practical applications prior to calculating the spectral radius itself. The most senior (1994) and popular indicator, R0(L), is known as the net reproductive rate, and we consider two others, R1(L) and RRT(A), developed later on. All the three are different in terms of their simplicity and the level of generality, and we illustrate them with a case study of Calamagrostis epigeios, a long-rhizome perennial weed actively colonizing open spaces in the temperate zone. While the R0(L) and R1(L) fail, respectively, because of complexity and insufficient generality, the RRT(L) does succeed, justifying the merit of indication.
On the Dimension of a New Class of Derivation Lie Algebras Associated to Singularities
Authors: Hussain Naveed , Yau Stephen S.-T. , Zuo Huaiqing
Published: July 2021

Let (V,0)={(z1,…,zn)∈Cn:f(z1,…,zn)=0} be an isolated hypersurface singularity with mult(f)=m. Let Jk(f) be the ideal generated by all k-th order partial derivatives of f. For 1≤k≤m−1, the new object Lk(V) is defined to be the Lie algebra of derivations of the new k-th local algebra Mk(V), where Mk(V):=On/((f)+J1(f)+…+Jk(f)). Its dimension is denoted as δk(V). This number δk(V) is a new numerical analytic invariant. In this article we compute L4(V) for fewnomial isolated singularities (binomial, trinomial) and obtain the formulas of δ4(V). We also verify a sharp upper estimate conjecture for the δ4(V) for large class of singularities. Furthermore, we verify another inequality conjecture: δ(k+1)(V)<δk(V),k=3 for low-dimensional fewnomial singularities.
Fuzzy Results for Finitely Supported Structures
Authors: Alexandru Andrei , Ciobanu Gabriel
Published: July 2021

We present a survey of some results published recently by the authors regarding the fuzzy aspects of finitely supported structures. Considering the notion of finite support, we introduce a new degree of membership association between a crisp set and a finitely supported function modelling a degree of membership for each element in the crisp set. We define and study the notions of invariant set, invariant complete lattices, invariant monoids and invariant strong inductive sets. The finitely supported (fuzzy) subgroups of an invariant group, as well as the L-fuzzy sets on an invariant set (with L being an invariant complete lattice) form invariant complete lattices. We present some fixed point results (particularly some extensions of the classical Tarski theorem, Bourbaki–Witt theorem or Tarski–Kantorovitch theorem) for finitely supported self-functions defined on invariant complete lattices and on invariant strong inductive sets; these results also provide new finiteness properties of infinite fuzzy sets. We show that apparently, large sets do not contain uniformly supported, infinite subsets, and so they are invariant strong inductive sets satisfying finiteness and fixed-point properties.
Deep-Sea Coral Garden Invertebrates and Their Associated Fungi Are Genetic Resources for Chronic Disease Drug Discovery
Authors: Marchese Pietro , Young Ryan , O’Connell Enda , Afoullouss Sam , Baker Bill , Allcock A. , Barry Frank , Murphy J.
Published: July 2021

Chronic diseases characterized by bone and cartilage loss are associated with a reduced ability of progenitor cells to regenerate new tissues in an inflammatory environment. A promising strategy to treat such diseases is based on tissue repair mediated by human mesenchymal stem cells (hMSCs), but therapeutic outcomes are hindered by the absence of small molecules to efficiently modulate cell behaviour. Here, we applied a high-throughput drug screening technology to bioprospect a large library of extracts from Irish deep-sea organisms to induce hMSC differentiation toward musculoskeletal lineages and reduce inflammation of activated macrophages. The library included extracts from deep-sea corals, sponges and filamentous fungi representing a novel source of compounds for the targeted bioactivity. A validated hit rate of 3.4% was recorded from the invertebrate library, with cold water sea pens (octocoral order Pennatulacea), such as Kophobelemnon sp. and Anthoptilum sp., showing the most promising results in influencing stem cell differentiation toward osteogenic and chondrogenic lineages. Extracts obtained from deep-sea fungi showed no effects on stem cell differentiation, but a 6.8% hit rate in reducing the inflammation of activated macrophages. Our results demonstrate the potential of deep-sea organisms to synthetize pro-differentiation and immunomodulatory compounds that may represent potential drug development candidates to treat chronic musculoskeletal diseases.
Blue Biotechnology: Computational Screening of Sarcophyton Cembranoid Diterpenes for SARS-CoV-2 Main Protease Inhibition
Authors: Ibrahim Mahmoud A. A. , Abdelrahman Alaa H. M. , Atia Mohamed A. M. , Mohamed Tarik A. , Moustafa Mahmoud F. , Hakami Abdulrahim R. , Khalifa Shaden A. M. , Alhumaydhi Fahad A. , Alrumaihi Faris , Abidi Syed Hani , Allemailem Khaled S. , Efferth Thomas , Soliman Mahmoud E. , Paré Paul W. , El-Seedi Hesham R. , Hegazy Mohamed-Elamir F.
Published: July 2021

The coronavirus pandemic has affected more than 150 million people, while over 3.25 million people have died from the coronavirus disease 2019 (COVID-19). As there are no established therapies for COVID-19 treatment, drugs that inhibit viral replication are a promising target; specifically, the main protease (Mpro) that process CoV-encoded polyproteins serves as an Achilles heel for assembly of replication-transcription machinery as well as down-stream viral replication. In the search for potential antiviral drugs that target Mpro, a series of cembranoid diterpenes from the biologically active soft-coral genus Sarcophyton have been examined as SARS-CoV-2 Mpro inhibitors. Over 360 metabolites from the genus were screened using molecular docking calculations. Promising diterpenes were further characterized by molecular dynamics (MD) simulations based on molecular mechanics-generalized Born surface area (MM-GBSA) binding energy calculations. According to in silico calculations, five cembranoid diterpenes manifested adequate binding affinities as Mpro inhibitors with ΔGbinding < −33.0 kcal/mol. Binding energy and structural analyses of the most potent Sarcophyton inhibitor, bislatumlide A (340), was compared to darunavir, an HIV protease inhibitor that has been recently subjected to clinical-trial as an anti-COVID-19 drug. In silico analysis indicates that 340 has a higher binding affinity against Mpro than darunavir with ΔGbinding values of −43.8 and −34.8 kcal/mol, respectively throughout 100 ns MD simulations. Drug-likeness calculations revealed robust bioavailability and protein-protein interactions were identified for 340; biochemical signaling genes included ACE, MAPK14 and ESR1 as identified based on a STRING database. Pathway enrichment analysis combined with reactome mining revealed that 340 has the capability to re-modulate the p38 MAPK pathway hijacked by SARS-CoV-2 and antagonize injurious effects. These findings justify further in vivo and in vitro testing of 340 as an antiviral agent against SARS-CoV-2.