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The formation of a S-shaped filament was investigated to determine if and how magnetoacoustic waves in the solar corona can trigger filament excitation. The study investigated how magnetoacoustic waves interact with two magnetic null points in the solar corona. Since the solar corona has a complex magnetic field structure, it is expected that magnetic structures are predominantly responsible for the occurrence of coronal events. Simulation methods are required because of the complex nature of the reconnection problem and the way MHD waves behave. Because of notable progress in the production of supercomputers and the enhancement of techniques, it is now possible to analyze the behaviour of nonlinear plasma near the magnetic null point through numerical methods. This article aims to explore the idea of a 2.5D null point pair and investigate the motion and generation of plasma flow resulting from a solitary magnetoacoustic pulse passing through a particular magnetic structure that contains two null points. In this statement, the PLUTO code, which is a type of code called Godunov, is used to solve a set of equations known as resistive magnetohydrodynamic equations. It was depicted that when transitioning from X-point to O-point, twisted formations are formed, which play a significant role in developing S-shaped filaments. These formations also have a vital function right before the excitement of the filaments. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Waste (polyethylene terephthalate) (PET) water bottles are among the most common plastic wastes in nature. These plastic wastes disappear within hundreds of years after they are released into nature. Therefore, it causes serious environmental pollution. Therefore, it is important to make these wastes reusable. This study aims to bring a new perspective to the reuse literature. It is aimed to produce smart polymer blend from waste PET, which is highly demanded and important in practical applications. Therefore, in this study, waste polymer PET was blended with smart polymer PLA into filament blends. The thermal properties of the blends were analysed by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA), chemical bond structures were determined by Attenuated Total Reflectance-Fourier transform infrared spectroscopy (ATR-FTIR spectroscopy) and shape memory tests were performed to determine whether the blends exhibit smart material properties. As a result of this study, it was observed that the thermal stability of the blended filaments varied according to the polymer ratio and the blend was characterized as an immiscible polymer blend. It was also found that the polymer blends exhibit shape memory properties. [ABSTRACT FROM AUTHOR]

Recently, there has been a significant global focus on the development of fully biobased, strong, and tough filaments. This paper presents a deep investigation into the reinforcing effect of chitin nanofibers (ChNFs) on the fabrication of robust cellulose nanofiber (CNF)-ChNF composite filaments. Three types of ChNFs were produced using distinct. Methods aqueous counter-collision (ChACC), acid hydrolysis (ChAH), and TEMPO-oxidization (ChTEMPO). Subsequently, these ChNFs were blended with CNFs derived from hardwood bleached-kraft pulp to create the nanocomposites. The CNFs underwent TEMPO-oxidization and aqueous counter-collision (ACC) treatment. The composite filaments were fabricated via wet spinning, followed by coagulation in a CaCl2 solution bath. A comparative analysis was conducted among all composites comprising various ChNFs and CNFs, examining their morphological, thermal, optical, and mechanical properties. Among them, the CNF-ChACC filament displayed the highest UV protection, while the CNF-ChAH filament demonstrated the highest tensile strength (614 MPa) and elongation-at-break, surpassing pure CNF filaments by 31.5% and 47%, respectively. It is anticipated that this study will contribute to a deeper understanding of the production of strong biobased filaments for advanced applications. [ABSTRACT FROM AUTHOR]

Femtosecond laser filament enables energy transfer over long distances, which is of great value for studying long-range ablation. However, the energy coupling of filament with the plasma generated by the ablation process leads to a very complex behavior which limits the ablation efficiency. This study systematically investigated the ablation mechanism of laser-induced filament in alumina ceramic. The plasma shock wave was initially investigated using spectral detection techniques combined with Sedov-Taylor theory. The results indicated that the maximum plasma shock wave reached 30 MPa under the irradiated by a 1 mJ fs laser. The theoretical analysis confirmed the effectiveness of the filament-induced plasma shock wave in enhancing the ablation rate of alumina ceramic. In this context, the experimental studies were conducted with varying filament positions and pulse energies, and the corresponding ablation rates for each parameter were investigated. The filament in the ablation process was found to has a secondary sputtering effect, which is an effective contributor to enhance the ablation rate. The corresponding ablation depth reach to 550 μm while achieving an ablation rate of 3.1 μm3/μJ. Finally, the coupling mechanism between the femtosecond laser filament and the plasma shock wave was systematically revealed. This research will facilitate future laser remote ablation applications with high efficiency. [ABSTRACT FROM AUTHOR]

To date, supercontinuum light in the visible and near‐infrared ranges is readily realizable by the optical Kerr effect through self‐phase modulation of ultrashort laser pulses in transparent media. However, it is still a challenge to extend the supercontinuum spectrum down to the deep‐ultraviolet (DUV) range, which is particularly needed for exploring ultrafast dynamics in chemistry, materials, and biology. Here, an approach of non‐resonant coherent Raman scattering is developed to generate ultra‐broadband visible‐DUV supercontinuum in ambient air with a spectral range spanning over 250 nm and a wavelength down to 220 nm. A rovibrational coherence is established in air molecules by filamentation of a near‐infrared femtosecond 800 nm pulse and two femtosecond Raman laser pulses at 267 and 400 nm are introduced into the coherent media to induce non‐resonant coherent Stokes and anti‐Stokes Raman scatterings, which serve as the spectral bridges to link the neighboring Raman pump laser spectra, resulting in ultra‐broadband supercontinuum light. The mechanism is further verified by examining the broadening of picosecond N2+ laser lines with narrow bandwidths (10–30 cm−1), which forms a supercontinuum spectrum spanning over 150 nm. The work provides a viable route for the establishment of coherent DUV supercontinuum in the gas media at designed wavelength ranges. [ABSTRACT FROM AUTHOR]

Given a metric continuum X, we consider the collection of all regular subcontinua of X and the collection of all meager subcontinua of X, these hyperspaces are denoted by D(X) and M(X), respectively. It is known that D(X) is compact if and only if D(X) is finite. In this way, we find some conditions related about the cardinality of D(X) and we reduce the fact to count the elements of D(X) to a Graph Theory problem, as an application of this, we prove in particular that | D ( X ) | ∉ { 2,3,4,5,8 , 9 } h t ) for any continuum X. Also, we prove that D(X) is never homeomorphic to ℕ . On the other hand, given a point p ∈ X , we consider the meager composant and the filament composant of p in X, denoted by MXp and FcsX(p), respectively, and we study some relations between MXp and FcsX(p) such as the equality of them as a subset of X. Also, we construct examples showing that the collection Fcs ( X ) = { FcsX ( p ) : p ∈ X } can be homeomorphic to: any finite discrete space, the harmonic sequence, the closure of the harmonic sequence and the Cantor set. Finally, we study the contractibility of M(X); we prove the arc of pseudo-arcs, which is a no contractible continuum, satisfies that its hyperspace of meager subcontinua is contractible, given a solution to an open problem. Also, we rise open problems.

In this study, we investigate the relationship between structure and properties of fiber–matrix adhesion for material extrusion–based 3‐dimensional (3D) printed composites. We examine the influence of fiber length and fiber content on the tensile properties of glass, basalt, and carbon fiber–reinforced polylactic acid (PLA) composites. Short fiber–reinforced filaments were produced, then, simple micromechanical models were used to predict the in‐plane tensile properties. We found that interlayer tensile properties are strongly influenced by fiber–matrix adhesion. If adhesion is sufficient, the fibers and matrix deform together under tensile load. A second‐order relationship describes interlayer tensile strength in relation to fiber content between 5 and 25 w%, with a maximum at 15 w%, for carbon and basalt fiber–reinforced composites. If adhesion is weak, the crack propagates along the fiber–matrix interface, causing brittle fracture and low strength. This behavior was noted for the glass fiber composite, for which the calculated interface shear strength was the lowest (1.4 MPa). In this case, fiber content is inversely proportional to interlayer tensile strength. Our results show the role of fiber–matrix adhesion quality on tensile properties, which has a major impact on both the accuracy of predictions and the damage processes. Highlights: Critical fiber length determines accuracy of tensile property estimatesQuality of fiber–matrix adhesion governs interlayer damage processPoor adhesion causes brittle fracture and low strengthSecond‐order relationship of interlayer tensile strength and fiber contentLoss of interlayer tensile strength in composite due to fiber–matrix interface [ABSTRACT FROM AUTHOR]

Introduction: We aim to examine how magnetic resistivity impacts the movement of magnetoacoustic waves near a magnetic null-point in the solar corona. Method: The resistive, nonlinear MHD simulations are solved by the PLUTO code in 2.5D for different amount of the resistivity. Results and Discussion: Propagation of magnetoacoustic waves in the vicinity of a magnetic null point has the potential to create current sheets with high current density excitation and plasmoid generation. During the entire duration of the simulation, it is discovered that plasma density became significant due to the plasmoid and also current density is high for high resistivity. It is depicted that high resistivity also leads to bigger plasmoids or magnetic islands in comparison to small resistivity. [ABSTRACT FROM AUTHOR]

The silkworm Nocardia infection model has been established as a useful animal model for screening the pathogenicity of Nocardia and evaluating the therapeutic effects of antimicrobial agents against Nocardia infection. No histopathological analysis of silkworms infected with Nocardia farcinica has yet been performed. In this study, we performed histological analyses on organs of silkworms infected with N. farcinica. One day after infection with N. farcinica, the organism developed a branching filamentous form from coccid cells in the hemolymph. In addition, we evaluated effective doses (ED50) values by treating infected silkworms with amikacin 30 seconds and 24 hours after infection and found that the ED50 values treated within 30 seconds and 24 hours after infection were 4.1 µg/larva and 5.6 µg/larva, respectively. Evaluation of treatment with amikacin against the infected silkworms was unaffected by the growth process form of Nocardia. These results suggest that the silkworm Nocardia infection model is a useful tool for evaluating the antimicrobial therapy in the growth process of the N. farcinica. [ABSTRACT FROM AUTHOR]

The current study explores the fabrication of 3D printing filament using waste glass powder (WGP) and high-density polyethylene (HDPE) thermoplastic aiming to enhance the mechanical properties and sustainability of the composite material. The matrix and filler were blended in varying weight ratios (HDPE: WGP) of 100:0, 95:5, 90:10, 85:15, and 80:20 to prepare a raw material for filament extrusion. The filament of diameter 1.65 ± 0.05 mm diameter was extruded. Thereafter, a chemical and thermo-mechanical characterization of extruded filament was conducted. Fourier-transform infrared spectroscopy (FTIR) analysis confirmed the successful integration of WGP into the HDPE matrix, while X-ray diffraction (XRD) examination revealed alterations in crystallinity attributed to WGP reinforcement. Thermogravimetric Analyzer (TGA) analysis demonstrated enhanced thermal stability upon WGP incorporation, which is attributed to its role as a thermal barrier. Tensile test exhibit 45.41% and 17.22% increase in yield stress and ultimate tensile stress for 90:10 composition ratio, respectively. Moreover, including waste glass powder in HDPE, thermoplastic composite offers a sustainable solution for repurposing glass waste, thereby reducing the volume of glass destined for landfills or incineration. Potential applications of this composite filament include its use in construction, automotive, and packaging industries through 3D printing, where improved mechanical properties and sustainability are highly valued. [ABSTRACT FROM AUTHOR]

Lignocellulosic waste materials are among the most abundant raw materials on Earth, and they have been widely studied as natural additives in materials, especially for polymer composites, with interesting results when it comes to improving physiochemical properties. The main components of these materials are cellulose, hemicellulose, and lignin, as well as small amounts of other polysaccharides, proteins, and other extractives. Several kinds of lignocellulosic materials, mainly fibers, have been evaluated in polymer matrices, and recently, the use of particles has increased due to their high surface area. Garlic is a spice seed that generates a waste husk that does not have applications, and there are no reports of industrial use of this kind of lignocellulosic material. Additive manufacturing, also known as 3D printing, is a polymer processing technique that allows for obtaining complex shapes that are hard to obtain with ordinary techniques. The use of composites based on synthetic polymers and lignocellulosic materials is a growing field of research. In the present work, the elaboration and evaluation of 3D-printed polypropylene–garlic husk particle (PP-GHP) composites are reported. First, the process of obtaining a filament by means of a single extrusion was carried out, using different GHP contents in the composites. Once the filament was obtained, it was taken to a 3D printer to obtain probes that were characterized using differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) was performed with the aim of evaluating the thermal behavior of the 3D-printed PP-GHP composites. According to the obtained results, the crystallization process and thermal stability of the PP-GHP composites were modified with the presence of GHP compared with pristine PP. Dynamic mechanical analysis (DMA) showed that the addition of GHP decreased the storage modulus of the printed composites and that the Tan δ peak width increased, which was associated with an increase in toughness and a more complex structure of the 3D-printed composites. X-ray diffraction (XRD) showed that the addition of GHP favored the presence of the β-phase of PP in the printed composites. [ABSTRACT FROM AUTHOR]

Filament-based material extrusion (MEX) represents one of the most commonly used additive manufacturing techniques for polymer materials. In a special variation of this process, highly filled polymer filaments are used to create metal parts via a multi-step process. The challenges associated with creating a dense final part are versatile due to the different and partly contrary requirements of the individual processing steps. Especially for processing in MEX, the compound must show sufficiently low viscosity, which is often achieved by the addition of wax. However, wax addition also leads to a significant reduction in ductility. This can cause filaments to break, which leads to failure of the MEX process. Therefore, the present study investigates the influence of different ethylene–propylene copolymers (EPCs) with varying ethylene contents as a ductility-enhancing component within the feedstock to improve filament processing behavior. The resulting feedstock materials are evaluated regarding their mechanical, thermal and debinding behavior. In addition, the processability in MEX is assessed. This study shows that a rising ethylene content within the EPC leads to a higher ductility and an enhanced filament flexibility while also influencing the crystallization behavior of the feedstock. For the MEX process, an ethylene fraction of 12% within the EPC was found to be the optimum regarding processability for the highly filled filaments in MEX and the additional processing steps to create sintered metal parts. [ABSTRACT FROM AUTHOR]

The correct conditions for measuring the luminescence intensities in fi laments formed by the action of femtosecond laser pulses were found for lithium fluoride crystals. The determined conditions ensured that the measured intensities were proportional to the concentrations of luminescent color centers created in the crystals by the laser radiation and allowed conclusions to be drawn about the processes occurring in the filaments. Near-cluster color centers were found, indicating the presence of nanosized clusters in all areas of the fi laments. [ABSTRACT FROM AUTHOR]

This scientific study, which brings completely new results, is characteristically divided into chapters where the authors deal with the extrusion mechanism, filament production, 3D printing of samples, and mechanical testing of samples. This research deals with a current topic in the field of production and testing of filaments composed of biodegradable polymers based on custom made PLA/PHB material. The authors of this study managed to produce and test a new type of biomaterial in the form of a filament called PLA BIOPOLYMER 20. The individual components forming this new type of material are described in the detailed statistics of this scientific article. After optimizing the parameters during single-screw extrusion on a filament maker, where the extrusion temperatures were set to 180° and the subsequent additive manufacturing of samples using FFF technology was started, where "dogbone type 5A" samples were printed. The authors managed to optimize the parameters of additive manufacturing and achieve significant results, which are also represented by individual printed samples, intended for subsequent mechanical testing, specifically for tensile testing. Important testing of materials for mechanical tensile tests was carried out according to generally applicable standards STN EN ISO 527-2, on the Inspekt table 5kN device. By mechanical testing, the individual stresses of the samples were determined. The average stress was 5.28 MPa. The authors compared the values obtained with samples printed from the new type of PLA BIOPOLYMER 20 material with the tension obtained with samples printed from pure PLA filament without admixture of other components. These tests are intended to determine the future application of the given material. This article brings new knowledge in the given field. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advanced Textile Technology is the property of Zhejiang Sci-Tech University Magazines and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plastic pollution causes serious environmental issues and endangers the health of humans and animals in both land and aquatic environments. Despite the fact that Nigeria produces hundreds of tons of plastic waste every day, a greater proportion still finds its way back into the ecosystem because only a small portion of it is recycled. Nigeria's growing production of single-use plastics and careless disposal of plastic waste into the land and ocean are the main causes of the country's growing plastic pollution problems.. For this reason, recycling and reusing plastics is necessary to lessen the harmful effects that plastic utilization has on both human and the environment.. Plastics can be recycled into filaments used in 3D printing also known as additive manufacturing. In this study, a plastic filament extrusion machine for waste plastic was designed and developed with the aim of recycling high-density polyethene, thereby lessening the negative environmental effects that come with disposing of it.. The basic components of the extruder comprised of a hopper, screw, barrel, die, and motor system. Temperature, oxygen, and shear stress all cause the plastics to deteriorate during the extrusion of plastics for filament.. Thus, this study examined the impact of different extrusion temperatures on the filament quality made from high-density polyethylene polyethene (HDPE). The plastic pellets melt and flow into the die as a result of friction between them and the barrel surface and the heat generated by the heating bands. Plastic filament was extruded with a combination of optimal pellet compression, temperatures between 150 and 230 degrees Celsius, and a gradual increase in the pressure of the molten pellets inside the barrel.. Melted plastic adhered itself to the barrel at low temperatures but turned to char at high temperature. Consequently, in order to produce quality 3D filament using HDPE, it is imperative to maintain acceptable temperature conditions. Based on the results, the extruder produced excellent filament suitable for 3D printing at 200 °C. The results of this study emphasize the significance of temperature regulation during the extrusion process in order to guarantee the intended filament quality. [ABSTRACT FROM AUTHOR]

A theoretical model is proposed that is capable of describing the current–voltage characteristic for a bipolar filament-type memristor during reversible switching. The model makes it possible to describe various types of current–voltage curves observed in experiments. It is established that the initially formed filament, after a series of switchings, acquires a stationary shape that repeatedly reproduces the current–voltage characteristic during further switchings. [ABSTRACT FROM AUTHOR]

This study aims to develop 3D printing filament composites that support sustainability and waste reduction goals by utilizing wood waste and recycled polypropylene. This study evaluated the effect of Maleic Anhydride Polyethylene (MAPE) and Maleic Anhydride Polypropylene (MAPP) compatibilizers on the mechanical properties of the filament. The study found that r-WoPPc filament with MAPP and MAPE had higher tensile strength compared to r-WoPPc with significant increments of 13% and 74%, respectively, compared to v-WoPPc. The flexural strength of r-WoPPc increased by 18% and 60% after adding optimum loading MAPP and MAPE, respectively. The finding also reveals a significant enhancement in the tensile and flexural strength of the composite, proportional to the increase in MAPP percentage. In contrast, as the MAPE content increases, the tensile strength and flexural strength of the r-WoPPc experience a gradual decrease. Consequently, the addition of MAPP and MAPE improved the interfacial adhesion between wood and polypropylene, as revealed by the surface morphology of the r-WoPPc tensile fractured surface. Moreover, the reduced water absorption in r-WoPPc is attributed to the enhanced interfacial adhesion between wood fibers and the r-PP matrix, associated with improved tensile and flexural strength. The highest tensile strength of r-WoPPc with MAPP absorbs 14% water, while the lowest tensile strength absorbs 26%. Likewise, the highest tensile strength of r-WoPPc with MAPE absorbs only 0.8% water, compared to the lowest strength, which absorbs 2% water. This study demonstrated the potential for producing 3D printing filament from recycled polypropylene and wood waste, which benefits sustainability. [ABSTRACT FROM AUTHOR]

Polyether-ether-ketone (PEEK) is a recently commonly used high-performance thermoplastic material with high heat resistance, high chemical resistance, high water resistance, and high wear resistance. Polyether-ether-ketone products with complex structures manufactured through the 3D printing process of fused filament fabrication (FFF) are emerging in the medical field. However, similar to other plastics, PEEK materials are also hygroscopic. This may have an impact on 3D printed products. The effect of storage time of filament on 3D printed PEEK products under specific temperature and humidity conditions has not been further explored. This study is mainly to explore the moisture absorption of PEEK filament for different storage time and the effect of moisture absorption on the performance of 3D printed PEEK products. The correlation between storage time and moisture absorption is verified by experiment. It is found that moisture will affect the surface quality of PEEK products. In addition, the mechanical test results show that the increase in the amount of water absorbed leads to the decrease of material properties, such as tensile strength, density, and hardness. Therefore, it is recommended to store unused or leftover PEEK filaments under vacuum drying conditions. For PEEK filaments that are being printed, it should be ensured to replace them every less than 24 h.Article Highlights: PEEK filament absorbed moisture over time, affecting 3D printed product surface quality. Longer storage time correlated with decreased mechanical properties of 3D printed PEEK. Unused PEEK filaments should be stored under vacuum drying conditions. [ABSTRACT FROM AUTHOR]

Enhancing typhoon forecasts hinges on a deeper understanding of the upper‐ocean's response and feedback mechanisms to typhoons. Presently, our knowledge of typhoon‐ocean interactions is largely derived from low‐resolution numerical simulations (often >10 km) and limited observations, which inadequately capture submesoscale processes (SPs) in the ocean. Connecting extreme typhoons to upper‐ocean SPs remains a challenge. This study reveals the formation of a distinctive vortex filament pool (VFP) in high‐resolution (∼1.2 km) numerical experiments. The experiments show that under specific conditions, typhoons can generate this visually striking phenomenon, displaying SP dynamics and kinematics typical of the upper ocean, with Rossby numbers and the nondimensional strain and divergence rates exceeding 2. The VFP formation is mainly driven by strain‐induced frontogenesis linked to the flow generated by Typhoon Nangka after a major turn. Initially, the pool consists of many near‐parallel filaments, but processes such as merging, stretching, and destabilization subsequently occur lead to numerous small vortices with a mean radius of ∼13 km. While the high‐resolution numerical experiments highlight phenomena requiring observational validation, they suggest the presence of natural processes previously undetectable with low‐resolution models and limited observations. This study underscores the need for enhanced observations and numerical models to better understand refined ocean dynamical processes. Plain Language Summary: Our understanding of the upper‐ocean's response and feedback to typhoons is limited by sparse observations and low‐resolution numerical models. High‐resolution numerical simulations have uncovered new features, revealing that under specific conditions, a vortex filament pool can form in the upper ocean following a super typhoon. Analysis shows that these filaments exhibit characteristics typical of upper ocean submesoscale processes. The pool then undergoes interesting processes like merging, stretching, and destabilization, resulting in numerous small vortices. Although these findings need further observational evidence, they highlight possible complex interactions among submesoscale processes. This emphasizes the critical need for better observational tools and enhanced numerical models to identify unfamiliar oceanic phenomena. Key Points: High resolution model results reveal a vortex filament pool left by a super typhoonThe filaments undergo merging, stretching, and eventually breaking into multiple smaller vorticesThe filament pool is produced by the strain‐induced frontogenesis associated with the flow induced by Typhoon Nangka after a major turn [ABSTRACT FROM AUTHOR]

Purpose: This article aims to present an overview of additive manufacturing technologies, including the latest research trends and a heuristic comparative analysis of the selected technologies group. Design/methodology/approach: Quantitative analysis of research articles from the past 5 years was performed using the most referred scientific databases - Scopus and Web of Science. Qualitative analysis included a State-of-the-Art overview of 3D printing by means of photopolymerization, material and binder jetting, extrusion techniques and powder fusion. Heuristic comparative analysis of the abovementioned technologies was performed using a dendrological matrix, considering the potential and attractiveness traits of the listed methods. Findings: The quantitative analysis results indicate that powder fusion technologies have received the most attention in the last 5 years. Heuristic procedural benchmarking analysis has found that Powder Bed Fusion is the most promising group of additive manufacturing technologies. Research limitations/implications: Presented review indicates that industrial applications of additive manufacturing are continuously growing, compared to other manufacturing technologies, such as casting, forming and subtractive treatment. The upward trend is expected to continue in the near future, and the range of practical industrial applications will expand rapidly. Practical implications: The quantitative, qualitative, and comparative analysis of additive manufacturing technologies presented in this article might be useful for researchers looking for interesting new research areas. The same applies to entrepreneurs interested in implementing modern additive manufacturing techniques in business practice. Originality/value: The value of this paper is the presentation of a wide spectrum of additive manufacturing technologies using various technical solutions and engineering materials, considering the latest development trends in their area. [ABSTRACT FROM AUTHOR]

Given a metric continuum X, we consider the collection of all regular subcontinua of X and the collection of all meager subcontinua of X, these hyperspaces are denoted by D(X) and M(X), respectively. It is known that D(X) is compact if and only if D(X) is finite. In this way, we find some conditions related about the cardinality of D(X) and we reduce the fact to count the elements of D(X) to a Graph Theory problem, as an application of this, we prove in particular that |D(X)| G {2, 3,4, 5, 8, 9} for any continuum X. Also, we prove that D(X) is never homeomorphic to N. On the other hand, given a point p G X, we consider the meager composant and the filament composant of p in X, denoted by Mpf and FcsX (p), respectively, and we study some relations between Mpx and FcsX (p) such as the equality of them as a subset of X. Also, we construct examples showing that the collection Fcs(X) = {FcsX (p): p G X} can be homeomorphic to: any finite discrete space, the harmonic sequence, the closure of the harmonic sequence and the Cantor set. Finally, we study the contractibility of M(X); we prove the arc of pseudo-arcs, which is a no contractible continuum, satisfies that its hyperspace of meager subcontinua is contractible, given a solution to Problem 3 of [10]. Most of the results shown in this paper are focus to answer problems and questions posed in [6], [9] and [10]. Also, we rise open problems. [ABSTRACT FROM AUTHOR]

The fabrication of a biodegradable polycaprolactone (PCL)/hydroxyapatite (HAp) scaffold prepared from local waste blue crab shells (Portunus pelagicus) by melt spinning method was investigated. The effect of different KH2PO4 concentrations on the physico‐chemical properties of HAp is evaluated. Furthermore, the influence of PCL/HAp ratios on mechanical strength and particle size distribution is reported. The formation of HAp is confirmed by Infrared (IR) spectroscopy and X‐ray diffraction (XRD). The biocompatibility of the PCL/HAp composites was evaluated using MTT assay and mechanical tests. The results reveal that the increase in KH2PO4 concentration contributed to the higher yield of HAp. However, the crystal and particle sizes are relatively invariable. SEM micrograph shows that the HAp introduction into PCL improves the material's porosity. Moreover, adding 10 % HAp into the PCL matrix significantly improved the mechanical strength of the filament compared to commercial PCL. MTT assay exhibits above 90 % cell viability, implying that the prepared PCL/HAp composite is non‐toxic and biocompatible with artificial bone replacement. After all, this study demonstrates that PCL/HAp filament derived from local blue crab waste is highly promising as a bone scaffolding material. [ABSTRACT FROM AUTHOR]

Low-temperature additive manufacturing of magnesium (Mg) alloy implants is considered a promising technique for biomedical applications due to Mg's inherent biocompatibility and 3D printing's capability for patient-specific design. This study explores the influence of powder volume content, size, and morphology on the mechanical properties and viscosity of polylactic acid (PLA) matrix composite filaments containing in-house-produced magnesium–calcium (Mg-Ca) particles, with a focus on their application towards low-temperature additive manufacturing. We investigated the effects of varying the Mg-Ca particle content in a PLA matrix, revealing a direct correlation between volume content and bending strength. Particle size analysis demonstrated that smaller particles (D50: 57 μm) achieved a bending strength of 63.7 MPa, whereas larger particles (D50: 105 μm) exhibited 49.6 MPa at 20 vol.%. Morphologically, the filament containing spherical particles at 20 vol.% showed a bending strength that was 11.5 MPa higher than that of the filament with irregular particles. These findings highlight the critical role of particle content, size, and shape in determining the mechanical and rheological properties of Mg-Ca/PLA composite filaments for use in material extrusion additive manufacturing. [ABSTRACT FROM AUTHOR]

Although various additive manufacturing techniques are used intensively to mold materials for solid oxide fuel cell (SOFC) applications, 3D printing has not been applied to obtain sealants which are crucial components for SOFC stacking. It is essential to develop different methods for molding sealing products based on glasses and glass-ceramics which are the most promising materials for SOFC stacking. This study reveals the potential of fused deposition modeling (FDM) for the production of complex shape objects for the sealing of tubular SOFC in the example of the composition based on thermoplastic, thermoplastic elastomer, oil, and a filler (glass sealant). The highest filler content in the mixture is 63 wt %. Two aluminosilicate sealants of different compositions are used as the filler and the printed products are successfully applied for tubular supporting anode|sealant|steel joints. • FDM is successfully used to obtain products for tubular SOFC sealing. • Bubbles in the sealant volume do not violate the sealing. • Tubular supporting anode|sealant|steel joints are prepared using printed products. [ABSTRACT FROM AUTHOR]

Agricultural waste is a renewable source of lignocellulosic components, which can be processed in a variety of ways to yield added-value materials for various applications, e.g., polymer composites. However, most lignocellulosic biomass is incinerated for energy. Typically, agricultural waste is left to decompose in the fields, causing problems such as greenhouse gas release, attracting insects and rodents, and impacting soil fertility. This study aims to valorise nonedible tomato waste with no commercial value in Additive Manufacturing (AM) to create sustainable, cost-effective and added-value PLA composites. Fused Filament Fabrication (FFF) filaments with 5 and 10 wt.% tomato stem powder (TSP) were developed, and 3D-printed specimens were tested. Mechanical testing showed consistent tensile properties with 5% TSP addition, while flexural strength decreased, possibly due to void formation. Dynamic mechanical analysis (DMA) indicated changes in storage modulus and damping factor with TSP addition. Notably, the composites exhibited antioxidant activity, increasing with higher TSP content. These findings underscore the potential of agricultural waste utilization in FFF, offering insights into greener waste management practices and addressing challenges in mechanical performance and material compatibility. This research highlights the viability of integrating agricultural waste into filament-based AM, contributing to sustainable agricultural practices and promoting circular economy initiatives. [ABSTRACT FROM AUTHOR]

Skeletal muscle is an important structure responsible for producing movement, storing nutrients, maintaining posture and providing stability across joints. Unlike smooth and cardiac muscle, control can be voluntary. This review article will outline the macroscopic and microscopic appearance of skeletal muscle, the method by which it contracts, the types of skeletal muscle and pathology associated with it. [ABSTRACT FROM AUTHOR]

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A new technique of additive prototyping filament volumetric nanostructuring based on the high-speed mechanical mixing of acrylonitrile-butadiene-styrene (ABS) copolymer granules and single-walled carbon nanotube (CNT) powder (without prior dispersion in solvents) is considered. The morphological spectra of scanning electron microscopy (SEM) images of nanostructured filament slice surfaces were obtained and characterized with the original mathematical simulation. The relations of structural changes in the "ingredient-matrix" polymer system with dielectric and mechanical properties of the ABS-based filaments were established. The supplementation of 1.5 mass.% of CNT powder to the ABS filament composition leads to the tensile strength increasing from 36 ± 2 to 42 ± 2 MPa. It is shown that the greater the average biharmonic amplitude and the morphological spectrum localization radius of the slice surfaces' SEM images, the lower the electrical resistance of the corresponding nanostructured filaments. The possibility of carbon nanotube-modified filament functional layers forming using the extrusion additive prototyping technique (FFF) on the surface of plasma-chemically modified PET substrates (for the creation of load cell elements) is experimentally demonstrated. [ABSTRACT FROM AUTHOR]

Filaments used in textile products have many design parameters such as length, diameter, tip shape, material properties, etc. In order to design and develop the products efficiently that satisfy the desired functions, it is important to estimate the mechanical properties of filaments with various design parameters and to quantify the effects of design parameters on the mechanical behavior. In this study, we focused on as one of the design parameters of textile products, and evaluated the effects of this parameter on the mechanical properties of filaments under the sliding behavior based on the numerical and experimental approach. The results had shown that the difference in the tip shape of filaments affects the load value applied to the contacting body. It was also shown that the difference in the tip shape affected the deformation behavior. The difference of the tip shape was caused by the strain energy density of filaments during sliding movement. We believed that the results obtained in this study would be useful for the design and development of textile products efficiently. [ABSTRACT FROM AUTHOR]

Based on data from the national waste information system, total waste in Indonesia in 2022 will be 36.1 million tons per year. Referring to this data, there is still a lack of waste processing and requires quite large costs for waste processing resulting from the increase in population, changes in consumption patterns and people's lifestyles. As a solution, researchers have developed a tool to make 3D printing filament using used bottles as the main material. The tool is equipped with a stepper motor that controls the process of winding plastic bottle tape into 3D printing filament. Regulating the rotation of the stepper motor and controlling the tool as a whole uses an Arduino UNO microcontroller and a potentiometer. Based on research results, on PET and PP bottles, speed control results were obtained for PET bottles using a speed of 49 rpm, the results obtained were good with a diameter of 1.75 mm. and for pp bottles it is at a speed of 26 rpm. For the PP type, good quality filament results were obtained with a diameter of 1.75 mm. in further research to use PID control so that PWM changes are more stable for motor rotation, use a power supply with a more stable output, and determine the right angle for cutting plastic bottles to produce the same cut. [ABSTRACT FROM AUTHOR]

The filament material extrusion (ME) process manufactures functional components for a wide range of personalized applications in medicine, fashion and remanufacturing cases, or customized batch production for aviation and automotive industries. Therefore, structural and welding parameters affect porosity during 3D printing and are of paramount interest concerning the parts' mechanical response to static and dynamic loadings. This work aims to arrange the literature's experimental findings of crucial processing parameters' effects on the fused filament fabrication (FFF) part's porosity and structural strength. Therefore, the materials and structure parameters, including the filament material properties, deposited strand geometry, infill rate, infill pattern design type and orientation, and part orientation, as well as welding parameters such as material flow, nozzle temperature, bed temperature, printing feed, and environmental conditions, are critically reviewed and study in profoundness regarding porosity and mechanical loading of 3D printed parts. Experimental studies are critically examined, emphasizing the effects of parameters and interactions between them. [ABSTRACT FROM AUTHOR]

Introduction: We aim to examine how magnetic resistivity impacts the movement of magnetoacoustic waves near a magnetic null-point in the solar corona.Method: The resistive, nonlinear MHD simulations are solved by the PLUTO code in 2.5D for different amount of the resistivity.Results and Discussion: Propagation of magnetoacoustic waves in the vicinity of a magnetic null point has the potential to create current sheets with high current density excitation and plasmoid generation. During the entire duration of the simulation, it is discovered that plasma density became significant due to the plasmoid and also current density is high for high resistivity. It is depicted that high resistivity also leads to bigger plasmoids or magnetic islands in comparison to small resistivity.

3-methylcrotonyl-CoA carboxylase (MCC) is a biotin-dependent mitochondrial enzyme necessary for leucine catabolism in most organisms. While the crystal structure of recombinant bacterial MCC has been characterized, the structure and potential polymerization of native MCC remain elusive. Here, we discovered that native MCC from Leishmania tarentolae (LtMCC) forms filaments, and determined the structures of different filament regions at 3.4, 3.9, and 7.3 Å resolution using cryoEM. α6β6 LtMCCs assemble in a twisted-stacks architecture, manifesting as supramolecular rods up to 400 nm. Filamentous LtMCCs bind biotin non-covalently and lack coenzyme A. Filaments elongate by stacking α6β6 LtMCCs onto the exterior α-trimer of the terminal LtMCC. This stacking immobilizes the biotin carboxylase domains, sequestering the enzyme in an inactive state. Our results support a new model for LtMCC catalysis, termed the dual-swinging-domains model, and cast new light on the function of polymerization in the carboxylase superfamily and beyond.

Consumer preferences for comfortable and well-fitting clothing have led to an increased demand for yarns (elastic) in denim fabric production. The study focuses on the manufacture of yarns (dual core) with various core components including T400® (Polyethylene terephthalate) / poly trimethylene terephthalate), PBT (Polybutylene terephthalate), Polyester (PES), and elastane (Lycra®) and their impact on denim fabric properties. The study involves the production of Ne 18/1 yarns (dual core) using an adjusted spinning method (ring) with elastane and different filaments in the core and additionally, twill (3/1 ‘Z’) fabric (denim) is manufactured using those yarns, and then fabric and yarn characteristics are evaluated. The results show significant variations in fabric and yarn characteristics based on the type of core material used. The yarn properties, such as the neps (+200), strength, thin place (-50), hairiness, elongation %, unevenness %, and thick place (+50) of yarns (dual core) are affected by the selection of filament. Fabric properties like weight, elasticity %, strength (tensile), strength (tearing), shrinkage %, and stiffness exhibit differences depending on the core filament. The statistical analysis employs one-way ANOVA to investigate the significance of differences in yarn and fabric properties within various core materials. The outcomes of this experimental work contribute valuable understandings of the production of yarns (dual core) with several filaments for enhancing fabric (denim) performance.

In recent years, metal chip powders obtained from solid-state processes have shown great potential as a sustainable raw material for powder technologies. The material and fragmentation process of the chips has a significant role in the final characteristics of the powder particles, such as size and particle size distribution, shape, surface, and structure, which are essential parameters to consider when converting chips to powder for applications. However, tool steel chips as a powder raw material have not yet been significantly studied. In this study, the steel chips were from machining AISI H13 steel and the milling process used a ball mill, and the challenge was to obtain powder particle sizes of around 20 µm with suitable properties from the application of envisaged material extrusion (MEX). A comparison study with the commercial raw material for MEX, such as powder metal filament extrusion, was performed. This study highlights the behaviors of chip powders during all steps of MEX, namely, feedstock and filament production, 3D object shaping, thermal de-binding, and sintering. A comparison of the mixture based on powder from chips and commercial powders for MEX was performed after evaluating the mixing torque of the powder and the system of binders and additives suitable for the rheological characteristics required for an extrusion mixture, and optimizing the binder removal and the sintering conditions. The 3D objects resulting from chip powders had a refined microstructure, showing an increase of 15% in the microhardness when compared with the those resulting from commercial powders.

The efficacy of current treatments is still insufficient for Alzheimer's disease (AD), the most common cause of Dementia. Out of the two pathological hallmarks of AD amyloid-ß plaques and neurofibrillary tangles, comprising of tau protein, tau pathology strongly correlates with the symptoms of AD. Previously, screening for inhibitors of tau aggregation that target recombinant tau aggregates have been attempted. Since a recent cryo-EM analysis revealed distinct differences in the folding patterns of heparin-induced recombinant tau filaments and AD tau filaments, this study focused on AD seed-dependent tau aggregation in drug repositioning for AD. We screened 763 compounds from an FDA-approved drug library using an AD seed-induced tau aggregation in SH-SY5Y cell-based assay. In the first screening, 180 compounds were selected, 72 of which were excluded based on the results of lactate dehydrogenase assay. In the third screening with evaluations of soluble and insoluble tau, 38 compounds were selected. In the fourth screening with 3 different AD seeds, 4 compounds, lansoprazole, calcipotriene, desogestrel, and pentamidine isethionate, were selected. After AD seed-induced real-time quaking-induced conversion, lansoprazole was selected as the most suitable drug for repositioning. The intranasal administration of lansoprazole for 4 months to AD seed-injected mice improved locomotor activity and reduced both the amount of insoluble tau and the extent of phosphorylated tau-positive areas. Alanine replacement of the predicted binding site to an AD filament indicated the involvement of Q351, H362, and K369 in lansoprazole and C-shaped tau filaments. These results suggest the potential of lansoprazole as a candidate for drug repositioning to an inhibitor of tau aggregate formation in AD. [ABSTRACT FROM AUTHOR]

Neuroepithelial cells (NECs) within the fish gill contain the monoamine neurochemical serotonin (5-HT), sense changes in the partial pressure of oxygen (PO2) in the surrounding water and blood, and initiate the cardiovascular and ventilatory responses to hypoxia. The distribution of neuroepithelial cells (NECs) within the gill is known for some fish species but not for the Gulf toadfish, Opsanus beta, a fish that has always been considered hypoxia tolerant. Furthermore, whether NEC size, number, or distribution changes after chronic exposure to hypoxia, has never been tested. We hypothesize that toadfish NECs will respond to hypoxia with an increase in NEC size, number, and a change in distribution. Juvenile toadfish (N = 24) were exposed to either normoxia (21.4 ± 0.0 kPa), mild hypoxia (10.2 ± 0.3 kPa), or severe hypoxia (3.1 ± 0.2 kPa) for 7 days and NEC size, number, and distribution for each O2 regime were measured. Under normoxic conditions, juvenile toadfish have similar NEC size, number, and distribution as other fish species with NECs along their filaments but not throughout the lamellae. The distribution of NECs did not change with hypoxia exposure. Mild hypoxia exposure had no effect on NEC size or number, but fish exposed to severe hypoxia had a higher NEC density (# per mm filament) compared to mild hypoxia-exposed fish. Fish exposed to severe hypoxia also had longer gill filament lengths that could not be explained by body weight. These results point to signs of phenotypic plasticity in these juvenile, lab-bred fish with no previous exposure to hypoxia and a strategy to deal with hypoxia exposure that differs in toadfish compared to other fish. [ABSTRACT FROM AUTHOR]