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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]

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]

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]

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.

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]

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]

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]

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]

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]

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.

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.

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]

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]

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]

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 Candida auris, an emerging multidrug-resistant fungal pathogen, predominately colonizes the human skin long term leading to subsequent life-threatening invasive infections. Fungal morphology is believed to play a critical role in modulating mucocutaneous antifungal immunity. In this study, we used an intradermal mouse model of C. auris infection to examine fungal colonization and the associated innate and adaptive immune response to yeast and filamentous C. auris strains. Our results indicate that mice infected with a filamentous C. auris had significantly decreased fungal load compared to mice infected with the yeast form. Mice infected with yeast and filamentous forms of C. auris stimulated distinct innate immune responses. Phagocytic cells (CD11b+Ly6G+ neutrophils, CD11b+Ly6Chi inflammatory monocytes, and CD11b+MHCII+CD64+ macrophages) were differentially recruited to mouse skin tissue infected with yeast and filamentous C. auris. The percentage and absolute number of interleukin 17 (IL-17) producing innate lymphoid cells, TCRγδ+, and CD4+ T cells in the skin tissue of mice infected with filamentous C. auris were significantly increased compared to the wild-type of yeast strain. Furthermore, complementation of filamentous mutant strain of C. auris (Δelm1 + ELM1) strain exhibited wild-type yeast morphology in vivo and induced comparable level of skin immune responses similar to mice infected with yeast strain. Collectively, our findings indicate that yeast and filamentous C. auris induce distinct local immune responses in the skin. The decreased fungal load observed in mouse skin infected with filamentous C. auris is associated with a potent IL-17 immune response induced by this morphotype.IMPORTANCECandida auris is a globally emerging fungal pathogen that transmits among individuals in hospitals and nursing home residents. Unlike other Candida species, C. auris predominantly colonizes and persists in skin tissue resulting in outbreaks of systemic infections. Understanding the factors that regulate C. auris skin colonization and host immune response is critical to develop novel preventive and therapeutic approaches against this emerging pathogen. We identified that yeast and filamentous forms of C. auris induce distinct skin immune responses in the skin. These findings may help explain the differential colonization and persistence of C. auris morphotypes in skin tissue. Understanding the skin immune responses induced by yeast and filamentous C. auris is important to develop novel vaccine strategies to combat this emerging fungal pathogen.

3D printing is one of the plastic recycling processes that deliver a mechanically sustainable product and may be used for 4D printing applications, such as self-assembly, sensors, actuators, and other engineering applications. The success and implementation of 4D printing are dependent on the tendency of the shape memory with the action of external stimuli, such as heat, force, fields, light, and pH. Acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) are the most common materials for fused filament fabrication-based 3D printing processes. However, the low-shaped memory tendency on heating and weaker and less rigidity of ABS limit the application domains. PLA is an excellent responsive behavior when the action of heat has high stiffness. The incorporation of PLA into ABS is one of the solutions to tune the shape memory effect for better applicability in the 4D printing domain. In this study, the primary recycled PLA was incorporated into the primary recycled ABS matrix from 5 to 40% (weight%), and composites were made by extrusion in the form of cylindrical filaments for 4D printing. The tensile and shape memory properties of the recycled ABS–PLA composites were investigated to select the best combination. The results of the study were supported by fracture analysis by shape memory analysis, scanning electron microscopy, and optical microscopy. This study revealed that the prepared ABS–PLA-based composites have the potential to be applied in self-assembly applications.

The preparation and characterization of filaments from janeng have been studied. The janeng filament (PCl-JS) process starts with the preparation and gelatinization of janeng starch, and then the resulting starch gelatinization, which is usually called thermoplastically processable starch (TPS) is carried out by filament processing by mixing PCl-g-GMA and JS at a temperature of 170 °C and 80 rpm for 15 min. The prepared filaments were analyzed. SEM studies show that the fracture surface of PCl-JS0 filaments provides a uniform fiber dispersion, in contrast to the morphology showing large and interconnected starch domains as the starch concentration increases from 1% to 9%. The intensity of hydrogen bonds observed in the spectrum via FTIR increased in band as the concentration of JS increased. XRD analysis observed that the crystallinity and crystal size of filaments without starch were higher than those of other PCl filaments that had undergone modification with starch. Mechanical analysis showed that starch did not have a negative effect on the tensile strength of the filaments, indicating good compatibility between JS and the PCl matrix. When the additional concentration of JS increased to 9%, the strength of PCl-JS filaments increased to 37 MPa, which was caused by the higher crystallinity induced by starch. The glass temperature of the filament sample was observed using DSC, which showed that PCl without JS occurred at 48.2 °C and shifted (+2 °C) towards 49.4 °C when JS was added. For all DSC curves, the exothermic peak was observed around 56–59 °C. The melt flow behavior of PCl-JS filaments decrease with increasing starch content.

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.

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.

This paper presents the development and characterization of cost-effective short Kevlar fiber reinforced nylon composite filaments. The effect of Kevlar fiber content on the tensile properties and the fiber distribution morphology was explored. A small amount of short Kevlar fiber was twin-screw compounded with nylon to study the reinforcing effects. Optical microscopy was used to investigate the morphology and the fiber distribution in the nylon matrix. The tensile strength of Kevlar composites increased to 90 MPa and 99 MPa at the fiber content of 1 wt% and 3 wt%, respectively, compared with the tensile strength of 84 MPa for pure nylon. As the fiber content increased from 0 to 3 wt%, the tensile modulus increased from 3.28 to 3.77 GPa. The optical microscopy and SEM images indicate that the twin-screw compounder with a proper screw configuration could disperse and distribute the Kevlar fibers uniformly in the nylon matrix. Statistically, this study demonstrates that the tensile strength and tensile modulus of nylon filament can be effectively enhanced with the addition of small amount of Kevlar fiber (i.e., less than 3 wt%), without sacrificing the ductility. [ABSTRACT FROM AUTHOR]

Lilies are important cut and pot flowers locally and globally; however, qualified planting materials from in vitro culture are still limited. The culture generally uses scales and leaves, while filaments and ovules are rarely utilized. Filaments and ovules of EXO CF/E, RDF CG/E, and DZ CG/E genotypes of Lilium sp. were explored for their potential to establish in vitro propagation protocol using different Chu N6 medium and their modifications. The 9.9 shoots/explant from 1.5 regenerative explants/replication of RDF CG/E filaments was proven on Chu N6 medium containing 6.79 µM 2,4-dichlorophenoxyacetic acid (2,4-D), 2.27 µM thidiazuron (TDZ), and 90 g L-1 sucrose; 3.3 regenerative explants/replication and 8.4 shoots/explant of EXO CF/E ovules were determined on Chu N6 medium with 2.26 µM 2,4-D, 6.81 µM TDZ and 90 g L-1 sucrose; and slightly improved on Chu N6 macro elements, full vitamins of MS basal medium with 3.39 µM 2,4-D, 3.41 µM TDZ, 150 ml L-1 coconut water (CW) and 60 g L-1 sucrose. The shoots were proliferated on the established media. The shoots of EXO CF/E, RDF CG/E and DZ CG/E genotypes produced varied leaves/shoot, leaf length, leaf width, roots/shoot, root length and bulb diameter on Chu N6 medium hormone free with 1.5% AC, followed by hardening them in a glass house for one month. The hardened-plantlets were acclimatized in plastic pots containing charcoal husk and bamboo compost (1:1) with 39.8-63.6% survivability. The protocol has the potential to be applied to other genotypes or lilies by specific improvements at the acclimatization stage. [ABSTRACT FROM AUTHOR]

Backround. Polymer products produced by 3D printing are inferior in strength characteristics to cast parts. To increase the strength characteristics, impact strength and heat resistance of products, a composite filament was created, and a technology for its production and use was developed. The purpose of the study is to develop technological regimes for the production and use of composite filament, to evaluate the mechanical properties of products obtained through layer-by-layer synthesis from the proposed composite material based on polyetheretherketone. Results. Equipment for the production of composite raw materials for 3D printing has been developed and the influence of technological modes on the quality of the resulting product has been studied. The results of assessing the mechanical properties of prototypes obtained by 3D printing from composite raw materials are presented.

In this work, we study the characteristics of femtosecond-filament-laser-matter interactions and laser-induced periodic surface structures (LIPSS) at a beam-propagation distance up to 55 m. The quantification of the periodicity of filament-induced self-organized surface structures was accomplished by SEM and AFM measurements combined with the use of discrete two-dimensional fast Fourier transform (2D-FFT) analysis, at different filament propagation distances. The results show that the size of the nano-scale surface features increased with ongoing laser filament processing and, further, periodic ripples started to form in the ablation-spot center after irradiation with five spatially overlapping pulses. The effective number of irradiating filament pulses per spot area affected the developing surface texture, with the period of the low spatial frequency LIPSS reducing notably at a high pulse number. The high regularity of the filament-induced ripples was verified by the demonstration of the angle-of-incidence-dependent diffraction of sunlight. This work underlines the potential of long-range femtosecond filamentation for energy delivery at remote distances, with suppressed diffraction and long depth focus, which can be used in biomimetic laser surface engineering and remote-sensing applications.

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-β 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.

Research has been conducted to analyze and characterize ten 3D printing materials as potential Radiological Phantoms of Lung Organs. Eight filaments of PLA, ABS, HIPS, Carbon, Nylon, TPU, PETG, and Wood were printed using an FDM type 3D printer, and two resins, PLA resin and Water washable resin, were printed using an SLA type 3D printer. The phantoms were printed with thickness variations of 3 mm, 6 mm, and 9 mm. 8 parameters were used to obtain the best material, namely material density, CT number, electron density (Ne), effective electron density (EDG), electron density per volume (EDV), effective atomic number (Zeff), material constituent elements, and elastic Modulus. Based on comparing the values of 8 parameters, the most potential to be used as phantom material for lung organs is PLA.

Lilies are important cut and pot flowers locally and globally; however, qualified planting materials from in vitro culture are still limited. The culture generally uses scales and leaves, while filaments and ovules are rarely utilized. Filaments and ovules of EXO CF/E, RDF CG/E, and DZ CG/E genotypes of Lilium sp. were explored for their potential to establish in vitro propagation protocol using different Chu N6 medium and their modifications. The 9.9 shoots/explant from 1.5 regenerative explants/replication of RDF CG/E filaments was proven on Chu N6 medium containing 6.79 µM 2,4-dichlorophenoxyacetic acid (2,4-D), 2.27 µM thidiazuron (TDZ), and 90 g L-1 sucrose; 3.3 regenerative explants/replication and 8.4 shoots/explant of EXO CF/E ovules were determined on Chu N6 medium with 2.26 µM 2,4-D, 6.81 µM TDZ and 90 g L-1 sucrose; and slightly improved on Chu N6 macro elements, full vitamins of MS basal medium with 3.39 µM 2,4-D, 3.41 µM TDZ, 150 ml L-1 coconut water (CW) and 60 g L-1 sucrose. The shoots were proliferated on the established media. The shoots of EXO CF/E, RDF CG/E and DZ CG/E genotypes produced varied leaves/shoot, leaf length, leaf width, roots/shoot, root length and bulb diameter on Chu N6 medium hormone free with 1.5% AC, followed by hardening them in a glass house for one month. The hardened-plantlets were acclimatized in plastic pots containing charcoal husk and bamboo compost (1:1) with 39.8-63.6% survivability. The protocol has the potential to be applied to other genotypes or lilies by specific improvements at the acclimatization stage.

Theoretical studies on oceans and large lakes have shown that submesoscale instabilities in frontal zones tend to reduce horizontal density gradients and enhance vertical density gradients, thereby re-stratifying the Surface Mixed Layer (SML). Submesoscale filament dynamics are primarily studied using numerical models and remote sensing imagery. However, in large lakes, this concept remains without substantial field validation, mainly due to the difficulty in conducting the necessary high-resolution water column measurements. Using a procedure we recently developed to predict the time and location of mesoscale and submesoscale features generated by strong wind fields, this work presents direct field evidence demonstrating the role of submesoscale cold filaments in re-stratifying the SML under weakly stratified conditions in a large lake (Lake Geneva). The dynamics of the observed filaments were further investigated with a high-resolution three-dimensional (3D) numerical model and Lagrangian particle-tracking. The numerical model accurately captured the formation of these filaments. The enhancement of thermal stratification strength, N², reached O(10-5) s-2 in areas adjacent to cold filaments under atmospheric cooling and heating conditions. In the pelagic zone (offshore), strong vertical velocities of O(100 m d-1) were associated with secondary circulation that rapidly transports and accumulates passive particles in the thermocline and hypolimnion layers, as confirmed by Acoustic Doppler Current Profiler (ADCP) backscattering intensity data. The field observations indicate that under weak stratification, Dissolved Oxygen (DO) variability reaches 0.5 mg l-1 near cold filaments. This documentation of strong vertical motions associated with submesoscale filaments is expected to contribute to the understanding of the vertical exchange of heat, contaminants and oxygen between the atmosphere and the pelagic zone of large lakes, as well as in oceans where carrying out such field measurements is very challenging. [ABSTRACT FROM AUTHOR]

The expansion and low cost of additive manufacturing technologies have led to a revolution in the development of materials used by these technologies. There are several varieties of materials that can be used in additive manufacturing by fused deposition modeling (FDM). However, some of the properties of these materials are unknown or confusing. This article addresses the need to know the thermal conductivity in different filaments that this FDM technology uses, because there are multiple applications for these additive manufacturing products in the field of thermal insulation. For the study of thermal conductivity, the DTC-25 commercial conductivity measurement bench was used, where the tests were carried out on a set of seven different materials with 100% fabrication density—from base materials such as acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA), to materials with high mechanical and thermal resistance such as thermoplastic polyurethane (TPU), polyether ether ketone (PEEK), and high-performance polyetherimide thermoplastic (ULTEM), to materials with metal inclusions (aluminum 6061) that would later be subjected to thermal after-treatments. This study shows how the parts manufactured with aluminum inclusions have a higher thermal conductivity, at 0.40 ± 0.05 W/m·K, compared to other materials with high mechanical and thermal resistance, such as TPU, with a conductivity of 0.26 ± 0.05 W/m·K. [ABSTRACT FROM AUTHOR]

This study investigates the effects of thermal treatment and silver nanoparticles on the mechanical and thermal properties of additively manufactured wood/polylactic acid (PLA) specimens. The 5 and 10 wt% additions of the wood flour into the PLA matrix are done in the twin screw extruder. The test specimens are produced from the filaments with a diameter of 1.75 mm using 3D printer. The mechanical properties of the 3D‐printed wood/PLA specimens are affected by the wood flour content, thermal treatment of wood, and silver nanoparticles. The 3D‐printed neat PLA specimens have better mechanical properties than the wood flour‐filled PLA specimens. The bending strength of the specimens enhances with increasing wood flour content while the tensile strength decreases. The increases in the mechanical properties reveal that the thermal treatment of the wood improves the compatibility between wood and PLA matrix, which hereby improves the interfacial adhesion. The addition of the silver nanoparticles positively affects the mechanical properties and it is more compatible with thermally modified wood particles as compared to the untreated wood particles. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printing has been used as a promising technology in biomedical sciences and engineering. However, there is a lack of ready-to-use feedstock for biomedical applications. In this work, a series of PLA biocomposite filled with calcium sulfate (CaS) particles up to a maximum content of 40 wt% has been prepared by solvent casting method and subsequently processed into filament form through the melt compounding method. The objective of this study was to investigate the processibility of composite filament with maximum ceramic content through fused filament fabrication (FFF) process to improve the mechanical, thermal and biological performance of virgin PLA for biomedical application. The composite filament was extruded at a temperature of 160 °C at a constant speed with an average diameter of 1.70 ± 08 mm, compatible with the 3D printer's feeding system. Morphological, thermal, mechanical, and crystallization analysis using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric (TGA) analysis was performed on the extruded filament to evaluate the effect of ceramic content in the polymeric matrix. The thermal stability was improved upon addition of CaS particles into the PLA matrix. Subsequently, PLA-CaS solid specimen was 3D-printed and characterized for its mechanical, and geometrical accuracy. The maximum compressive strength obtained is 115 MPa for 20% ceramic loading, which then decreases with increased ceramic content. The biocompatibility test using MC3T3E1 cells confirmed zero cytotoxicity and cell grows well on all PLA and composite specimen. The results revealed that the composite biomaterials could be easily printed even at high ceramic loading and maintain their structural integrity and stability during the additive manufacturing process. These composites could be potential candidates for various biomedical applications, such as bone scaffolds and bioresorbable screws for Anterior Cruciate Ligament (ACL) reconstruction. [Display omitted] [ABSTRACT FROM AUTHOR]

Composite 3D printing filaments integrating antimicrobial nanoparticles offer inherent microbial resistance, mitigating contamination and infections. Developing antimicrobial 3D-printed plastics is crucial for tailoring medical solutions, such as implants, and cutting costs when compared with metal options. Furthermore, hospital sustainability can be enhanced via on-demand 3D printing of medical tools. A PLA-based filament incorporating 5% TiO2 nanoparticles and 2% Joncryl as a chain extender was formulated to offer antimicrobial properties. Comparative analysis encompassed PLA 2% Joncryl filament and a TiO2 coating for 3D-printed specimens, evaluating mechanical and thermal properties, as well as wettability and antimicrobial characteristics. The antibacterial capability of the filaments was explored after 3D printing against Gram-positive Staphylococcus aureus (S. aureus, ATCC 25923), as well as Gram-negative Escherichia coli (E. coli, ATCC 25922), and the filaments with 5 wt.% embedded TiO2 were found to reduce the viability of both bacteria. This research aims to provide the optimal approach for antimicrobial and medical 3D printing outcomes. [ABSTRACT FROM AUTHOR]

The successful integration of hot-melt extrusion (HME) and fused deposition modelling (FDM) depends on a better understanding of the impact of environmental conditions on the printability of formulations, since they significantly affect the properties of the raw materials, whose control is crucial to enable three-dimensional printing (3DP). Hence, the objective of this work was to investigate the correlation between the environmental settings and the properties of paroxetine (PRX)-loaded filaments, previously produced by HME, which affect printability by FDM. The influence of different drying methods of the physical mixtures (PMs) and HME-filaments (FILs) on the quality and printability of these products was also assessed. The printability of FILs was evaluated in terms of the water content, and the mechanical and thermal properties of the products. Stability studies and physicochemical, thermal, and in vitro dissolution tests were carried out on the 3D-printed tablets. Stability studies demonstrated the high ductility of the PRX loaded FILs, especially under high humidity conditions. Under low humidity storage conditions (11% RH), the FILs became stiffer and were successfully used to feed the FDM printer. Water removal was slow when carried out passively in a controlled atmosphere (desiccator) or accelerated by using active drying methods (heat or microwave). Pre-drying of the PRX/excipients and/or PMs did not show any positive effect on the printability of the FIL. On the contrary, dry heat and, preferably, microwave mediated drying processes were shown to reduce the holding time required for successful FDM printing, enabling on-demand production at the point of care. [ABSTRACT FROM AUTHOR]

A linear stability analysis is carried out for viscoelastic filaments (formed by an unentangled polymer solution) during capillary thinning in the regime of unfolded polymer coils taking into account the relative motion of the solvent and the polymer. The conditions for the onset of filament instability with respect to axisymmetric modulation of its surface are found. The analysis is valid for relatively fast processes occurring at times shorter than the characteristic thinning time. It is shown that the growth rate of such pearling instability is determined by the osmotic modulus of the solution and the degree of orientation of macromolecules. In the case of nonassociative polymers, the instability develops (with the growth rate exceeding the rate of filament thinning) when the longitudinal length of stretched polymer chains exceeds the diameter of the filament. The theory is also applicable to soft gels and associative polymer solutions with very long relaxation times. The predictions of the theory are in agreement with experimental data. [ABSTRACT FROM AUTHOR]

SUMMARY: Switch defective/sucrose non‐fermentable (SWI/SNF) chromatin remodeling complexes are evolutionarily conserved, multi‐subunit machinery that play vital roles in the regulation of gene expression by controlling nucleosome positioning and occupancy. However, little is known about the subunit composition of SPLAYED (SYD)‐containing SWI/SNF complexes in plants. Here, we show that the Arabidopsis thaliana Leaf and Flower Related (LFR) is a subunit of SYD‐containing SWI/SNF complexes. LFR interacts directly with multiple SWI/SNF subunits, including the catalytic ATPase subunit SYD, in vitro and in vivo. Phenotypic analyses of lfr‐2 mutant flowers revealed that LFR is important for proper filament and pistil development, resembling the function of SYD. Transcriptome profiling revealed that LFR and SYD shared a subset of co‐regulated genes. We further demonstrate that the LFR and SYD interdependently activate the transcription of AGAMOUS (AG), a C‐class floral organ identity gene, by regulating the occupation of nucleosome, chromatin loop, histone modification, and Pol II enrichment on the AG locus. Furthermore, the chromosome conformation capture (3C) assay revealed that the gene loop at AG locus is negatively correlated with the AG expression level, and LFR‐SYD was functional to demolish the AG chromatin loop to promote its transcription. Collectively, these results provide insight into the molecular mechanism of the Arabidopsis SYD‐SWI/SNF complex in the control of higher chromatin conformation of the floral identity gene essential to plant reproductive organ development. Significance Statement: This study provides insight into the molecular mechanism of the Arabidopsis SYD‐SWI/SNF complex in the control of higher chromatin conformation of the floral identity gene essential to plant reproductive organ development. [ABSTRACT FROM AUTHOR]

Desminopathy is the most common intermediate filament disease in humans. The most frequent mutation causing desminopathy in patients is a R350P DES missense mutation. We have developed a rat model with an analogous mutation in R349P Des. To investigate the role of R349P Des in mechanical loading, we stimulated the sciatic nerve of wild-type littermates (WT) (n = 6) and animals carrying the mutation (MUT) (n = 6) causing a lengthening contraction of the dorsi flexor muscles. MUT animals showed signs of ongoing regeneration at baseline as indicated by a higher number of central nuclei (genotype: P

The atomic structure of the complete myosin tail within thick filaments isolated from Lethocerus indicus flight muscle is described and compared to crystal structures of recombinant, human cardiac myosin tail segments. Overall, the agreement is good with three exceptions: the proximal S2, in which the filament has heads attached but the crystal structure doesn't, and skip regions 2 and 4. At the head-tail junction, the tail α-helices are asymmetrically structured encompassing well-defined unfolding of 12 residues for one myosin tail, ∼4 residues of the other, and different degrees of α-helix unwinding for both tail α-helices, thereby providing an atomic resolution description of coiled-coil "uncoiling" at the head-tail junction. Asymmetry is observed in the nonhelical C termini; one C-terminal segment is intercalated between ribbons of myosin tails, the other apparently terminating at Skip 4 of another myosin tail. Between skip residues, crystal and filament structures agree well. Skips 1 and 3 also agree well and show the expected α-helix unwinding and coiled-coil untwisting in response to skip residue insertion. Skips 2 and 4 are different. Skip 2 is accommodated in an unusual manner through an increase in α-helix radius and corresponding reduction in rise/residue. Skip 4 remains helical in one chain, with the other chain unfolded, apparently influenced by the acidic myosin C terminus. The atomic model may shed some light on thick filament mechanosensing and is a step in understanding the complex roles that thick filaments of all species undergo during muscle contraction.

A new chapter in the pharmaceutical industry has been created by 3D printing, particularly in the manufacturing of solid preparations. This technology can support the modification of medicine in terms of drug dosage. Furthermore, it is achieved by adjusting the volume of tablets while being designed using the software to meet the required dose. The research aims to review several polymers used in 3D printing through the fused deposition modeling (FDM) technique. The polymers in filament fabrication for 3D printed tablets should be thermoplastic and have the appropriate mechanical properties for further processing steps. This review focuses on studying the characteristics of polymers such as polylactic acid, polyvinyl alcohol, polycaprolactone, polyvinyl pyrrolidone, polyethylene oxide, ethylene vinyl acetate, ethyl cellulose, hydroxypropyl methyl cellulose, and hydroxypropyl cellulose. Additionally, it discusses the effect of these polymers on the drug release profile from the 3D printed tablets.

Abstract This study investigates the effects of thermal treatment and silver nanoparticles on the mechanical and thermal properties of additively manufactured wood/polylactic acid (PLA) specimens. The 5 and 10 wt% additions of the wood flour into the PLA matrix are done in the twin screw extruder. The test specimens are produced from the filaments with a diameter of 1.75 mm using 3D printer. The mechanical properties of the 3D‐printed wood/PLA specimens are affected by the wood flour content, thermal treatment of wood, and silver nanoparticles. The 3D‐printed neat PLA specimens have better mechanical properties than the wood flour‐filled PLA specimens. The bending strength of the specimens enhances with increasing wood flour content while the tensile strength decreases. The increases in the mechanical properties reveal that the thermal treatment of the wood improves the compatibility between wood and PLA matrix, which hereby improves the interfacial adhesion. The addition of the silver nanoparticles positively affects the mechanical properties and it is more compatible with thermally modified wood particles as compared to the untreated wood particles.

Theoretical studies on oceans and large lakes have shown that submesoscale instabilities in frontal zones tend to reduce horizontal density gradients and enhance vertical density gradients, thereby re-stratifying the Surface Mixed Layer (SML). Submesoscale filament dynamics are primarily studied using numerical models and remote sensing imagery. However, in large lakes, this concept remains without substantial field validation, mainly due to the difficulty in conducting the necessary high-resolution water column measurements. Using a procedure we recently developed to predict the time and location of mesoscale and submesoscale features generated by strong wind fields, this work presents direct field evidence demonstrating the role of submesoscale cold filaments in re-stratifying the SML under weakly stratified conditions in a large lake (Lake Geneva). The dynamics of the observed filaments were further investigated with a high-resolution three-dimensional (3D) numerical model and Lagrangian particle-tracking. The numerical model accurately captured the formation of these filaments. The enhancement of thermal stratification strength, N2, reached O(10-5) s-2 in areas adjacent to cold filaments under atmospheric cooling and heating conditions. In the pelagic zone (offshore), strong vertical velocities of O(100 m d-1) were associated with secondary circulation that rapidly transports and accumulates passive particles in the thermocline and hypolimnion layers, as confirmed by Acoustic Doppler Current Profiler (ADCP) backscattering intensity data. The field observations indicate that under weak stratification, Dissolved Oxygen (DO) variability reaches 0.5 mg l-1 near cold filaments. This documentation of strong vertical motions associated with submesoscale filaments is expected to contribute to the understanding of the vertical exchange of heat, contaminants and oxygen between the atmosphere and the pelagic zone of large lakes, as well as in oceans where carrying out such field measurements is very challenging.

The mechanical properties improving filler introduction into polymer filaments often lead to the formation of defects in 3D-printed products. Studying the bulk modification of polyethylene terephthalate glycol (PETG) filaments with 0.5–1.5 wt% of natural shungite and molybdenum disulfide, we found the melt flow index (MFI) value reduced by 18%–30%. We investigate the effect of bulk modification on the filaments' rheological properties, develop a technique that eliminates typical additive prototyping defects by regulation of the extrusion parameters in Cura slicing software, and propose an effective method for the MFI-measurement of the 3D-printed filaments that does not require special laboratory equipment (plastometers). [ABSTRACT FROM AUTHOR]

Ocean dynamics at the submesoscale play a key role in mediating upper‐ocean energy dissipation and dispersion of tracers. Observations of ocean currents from synoptic mesoscale surveys at submesoscale resolution (250 m–100 km) from a novel airborne instrument (MASS DoppVis) reveal that the kinetic energy spectrum in the California Current System is nearly continuous from 100 km to sub‐kilometer scales, with a k−2 spectral slope. Although there is not a transition in the kinetic energy spectral slope, there is a transition in the dynamics to non‐linear ageostrophic interactions at scales of O $\mathcal{O}$(1 km). Kinetic energy transfer across spatial scales is enabled by interactions between the rotational and divergent components of the flow field at the submesoscale. Kinetic energy flux is patchy and localized at submesoscale fronts. Kinetic energy is transferred both downscale and upscale from 1 km in the observations of a cold filament. Plain Language Summary: Ocean dynamics at scales of 100 m–10 km, called the submesoscale, are important because they are associated with large velocity gradients and non‐linear interactions. Large gradients lead to vertical velocity, which facilitates ocean‐atmosphere interactions and ocean biological processes. Velocity gradients and non‐linear processes combine to transfer kinetic energy from the large‐scale flow to small‐scale perturbations. This can lead to instabilities that dissipate energy in the ocean surface layer (rather than the seafloor). Here we analyze novel observations that provide insight into ocean dynamics through the distributions of velocity gradients and energy transfer at 1 km scale. Dynamics at these scales have previously been modeled, but have not been observed directly. We observe a transition where non‐linear dynamics become more important at scales of order 10 km. We also introduce new interpretations of spectral analysis (analysis of energy and correlations across scales). Moreover, we analyze covariance of velocity gradient quantities and flow energetics to demonstrate that energy flux is episodic and localized at fronts. Together, these observations demonstrate that fronts play an important role in boundary‐layer kinetic energy processes and highlight the evolution of upwelling filaments. Key Points: Remote sensing observations reveal a kinetic energy spectrum with a continuous slope from 100 to 1 km in an eastern boundary regionBetween 1 and 10 km, ageostrophic non‐linear interactions become dynamically importantCross‐scale kinetic energy transfers computed from 2D velocity observations are associated with shear strain in the observed front [ABSTRACT FROM AUTHOR]