Small Beads Research Articles

CaO-B2O3-SiO2 glass fibers for wound healing

It was reported by Jung and Day in 2011 that a cotton-like glass fiber pad made of borate glass 13-93B3 demonstrated a remarkable wound healing effect. It was approved for sale as a novel wound dressing in the management of acute and chronic wounds in 2016. However, the detailed mechanism of its wound healing effect has not been reported. In the present study, glass fibers of different composition in the system CaO-B2O3-SiO2 were prepared and their in vitro properties investigated to determine the role of the constituent components in wound healing. Fine glass fibers that were 0.6–2.0 μm in diameter were obtained by a melt blown method. However, these fibers were accompanied by small glass beads because of the low viscosity of the glass melts. 13-93B3 glass released an appreciable amount of borate and calcium ions into simulated body fluid (SBF). The amounts of these released ions decreased with partial replacement of the B2O3 in 13-93B3 with SiO2. The addition of large amounts of the borate and calcium ions into the culture medium decreased the viability of the L929 fibroblasts. Partial replacement of the B2O3 in 13-93B3 with SiO2 induced the formation of an apatite-like phase amenable to the adsorption of biological components on its surface in SBF. The wound healing effect of these glass fibers of different composition is worth examining in future animal experiments.

Preparation of glass-like carbon with micrometer-sized pores by mixing thermosetting resin with thermoplastic microbeads

Glass-like carbon (GLC) is an agranular carbon material with a pseudo-glass-like appearance on the surface and fractured face. In this study, GLCs with numerous micrometer-sized pores were prepared by mixing thermosetting resins with two sizes of thermoplastic microbeads. For these GLCs, the carbonization yields and apparent densities decreased when they were mixed with microbeads. SEM results suggested that the surfaces and fracture faces of GLCs mixed with small beads possess smaller pores compared to those prepared with large beads. The electrical resistances of GLCs with small beads heat-treated at 1000 ℃ or above were almost unchanged compared to those of the neat GLCs.

Shape, size, and polymer dependent effects of microplastics on Daphnia magna

The effects of microplastic (MP) pollution on organisms are gaining increasing attention. To date, a variety of polymers of different shapes and sizes are used in ecotoxicology. Although polystyrene (PS) is the predominant polymer type used in effect studies, it is still unclear whether the observed effects derive from the polymer itself or from a certain particle shape and size. To elucidate whether the effects are polymer specific, we conducted a systematic study on Daphnia magna by comparing various PS-MPs to nonplastic control particles with similar properties. In chronic exposure experiments, we used PS beads (6 µm; 20 µm), fibers (Ø 3 µm, length: 75.5 µm), and fragments (5.7 µm; 17.7 µm) in two different size classes and two different concentrations (500 and 5000 particles ml-1) and in-house-produced control particles of comparable size, shape, concentration and, if possible, density. Although most PS properties did not elicit effects on the tested endpoints, we observed sublethal effects on D. magna life history and morphology for small PS beads and fragments. Interestingly, no adverse effects were detected for any of the control particles. Hence, the observed effects are polymer-specific, related to the size and shape of the polymer, and do not result from particle exposure per se.

PENERAPAN BEADING EMBROIDERY DENGAN KOMBINASI CABOCHON TECHNIQUE SEBAGAI HIASAN PADA EVENING GOWN

Evening gown is one type of party dress that is divided according to the time of use, namely late afternoon or late evening. Evening gowns usually have more prominent characteristics than other types of party dress. Both of the model and decoration/garniture. The application of beads as an evening gown decoration is one way to impress a luxurious impression of evening party dress. Beads or in English called "beads" comes from the Middle English bede which means "prayer" (object of Worship). Because at first the beads were associated with occult things in previous religious ceremonies. Beads are usually made of stone, bone, wood, shell, glass, metal, and so on. The technique of stringing beads is known as beading embroidery. Beading embroidery is usually done by stringing beads on fabric using the help of a needle and thread. One of the techniques in making beading embroidery is the Cabochon technique. The term of Cabochon comes from French which means head, this term is often used for gemstones that have been polished so that it has a smooth round shape. In its development, the cabochon is decorated with small beads strung around a large gemstone which is likened to the head or center of this ornament..The study aims to 1) To apply the knowledge obtained from the course milineris accessories and Houte Couture as the basis in making milineris accessoires and garniture on the evening gown. 2) To introduce beading embroidery especially the cabochon technique as one of the alternative for garniture or ornament on the evening gown,and 3) To improve the student’s creativities in making garniture on the evening gown through making beading embroidery with cabochon technique. This kind of study is experimental study. The method used is the PBL (Project Base Learning) method. Namely learning methods that use projects / activities as a medium by conducting exploration, assessment, interpretation, synthesis, and information to produce various forms of learning outcomes.

Production of endo-β-mannanase, superoxide radicals, hydrogen peroxide, and peroxidase in the micropylar endosperm of pepper seed during germination is determined by the endosperm itself

Cell wall-loosening enzymes and non-enzymatic factors have been demonstrated to be expressed specifically in the micropylar endosperm during seed germination, but the reason remains poorly understood. In this study, we used pepper seeds as plant materials to investigate this. At first, we showed that endo-β-mannanase, O2.−, H2O2, and ∙OH production-related peroxidase were tissue-specifically expressed also in the micropylar endosperm prior to radicle protrusion and thus played important roles in seed germination. Next, we incubated isolated de-embryonated seed halves with endosperm and seed coat but without embryo (shorted as endosperm-halves) alone in the water and found that they could still produce endo-β-mannanase, O2∙־, H2O2, and peroxidase specifically in the micropylar endosperm. We also utilized small glass beads to mimic radicles to touch onto the lateral areas of the incubated isolated endosperm-halves but found no endo-β-mannanase, O2∙־, H2O2, and peroxidase were induced specifically in the touched areas. Therefore, we propose that tissue-specific production of endo-β-mannanase, O2∙־, H2O2, and peroxidase in the micropylar endosperm is determined by the endosperm itself.

Electrospun antibacterial and antiviral poly(ε-caprolactone)/zein/Ag bead-on-string membranes and its application in air filtration

In this study, poly (ε-caprolactone) (PCL)/zein/Ag nanoparticle (AgNP) fibrous membranes were prepared by ultrasonication-assisted electrospinning. The effects of the AgNP content and ultrasonication time on the membrane morphology, chemical structure, biodegradability, mechanical properties, antibacterial/antiviral activity, and air filtration performance were studied. The best-performing membrane (AgNP content = 1% (w/v), sonication time = 30 min) exhibited a bead-on-string morphology, an air permeability of 93.6 ± 1.5 mm s−1, and the Escherichia coli and Staphylococcus aureus removal efficiencies of 98.1 ± 1.2% and 97.4 ± 2.5%, respectively. In an experiment with E. coli phage, the above-mentioned membrane exhibited a 97.1 ± 2.1% virus removal efficiency after 60 min. The high performance of this bead-on-string membrane for air filtration was ascribed to the low packing density due to the presence of open interconnected beaded airflow channels and small beads.

Automated Planning for Robotic Multi-Resolution Additive Manufacturing

Abstract Conventional material extrusion additive manufacturing (AM) processes require the user to make a trade-off between surface quality and build time of the part. A large bead filament deposition can speed up the build process; however, it leads to surfaces with high roughness due to the stair-stepping effect. The surface quality can be improved by using a small bead filament deposition, which increases the build time of the part. We present a new approach incorporating hybrid multi-resolution layers in material extrusion additive manufacturing to provide excellent surface quality without increasing the build time. Our slicing algorithm generates planar layers with large filaments to fill the interior regions in less time. The generated exterior layers are conformal and use small filaments to reduce the stair-stepping effect and improve surface quality. We also present a path planning algorithm to build parts with a single manipulator using a multi-nozzle extrusion tool. The path planning algorithm generates a smooth material deposition path by avoiding collision between the tool and the already built layers. It reduces the collision checks and performs collision detection in a computationally efficient manner. We build five parts to validate our approach and illustrate the benefits of multi-resolution AM.

The application of an innovative integrated Swiss-roll-combustor/Stirling-hot-end component on an unpressurized Stirling engine

An innovative integrated Swiss-roll-combustor/Stirling-hot-end component is proposed in this paper. A power generation system in conjunction with a Stirling engine is also built around the component and tested. The Stirling engine is a compact-size, unpressurized, γ-type engine that uses air as working gas. The Swiss-roll combustor is laden with small catalytic beads to decrease the ignition temperature and improve combustion efficiency. Experiments respectively burning dimethyl ether and syngas were conducted to better understand the potential of the system on tapping into green biomass energy. The marriage between the Swiss-roll combustor and the Stirling engine’s hot end offers many advantages as follows: The structural support from the spiral-channel wall in the Swiss-roll combustor enables the bottom wall of the Stirling engine to be made very thin, which improves the rate of heat transfer from the heat source to the engine significantly. Meanwhile, the system inherits those advantageous features in combustion from the Swiss-roll combustor, including a broader range of fuel/air ratio, higher combustion efficiency, and higher efficiency in harvesting the heat of flue gas. Compared to the predecessor of the present engine, the incorporation of the proposed component is proven to improve engine’s performance remarkably. In the experiment of burning dimethyl ether, the system produced 18.7 W of electric power and achieved 2.4% thermal to electric efficiency under a temperature difference of 254 °C. Such performance is remarkable among atmospheric-pressure Stirling engines. The proposed component has accomplished its design goal and would hopefully inspire new ideas for the development of green-energy Stirling-engine power generation systems in the future.

The Biology of Evaluating Skin-Care Products

The goal of this inquiry activity is to evaluate a variety of skin-care products on simulated skin cells using Orbeez, a brand of superabsorbent polymers. These small beads can quickly absorb water but will dry out in the air, thus perfectly representing our own skin cells. This property makes Orbeez an acceptable model for human skin, and test material for evaluating various skin-care products. Students will observe the quantitative changes that happened to the mass of the samples to determine the percent change. They will also observe the qualitative changes that happened throughout the lab investigation and record their observations in a lab notebook. After completing the experiment, students will create a presentation of the quantitative and qualitative results.

Application of Engineered Zinc Finger Proteins Immobilized on Paramagnetic Beads for Multiplexed Detection of Pathogenic DNA.

Micro-scale magnetic beads are widely used for isolation of proteins, DNA, and cells, leading to the development of in vitro diagnostics. Efficient isolation of target biomolecules is one of the keys to developing a simple and rapid point-of-care diagnostic. A zinc finger protein (ZFP) is a double-stranded (ds) DNA-binding domain, providing a useful scaffold for direct reading of the sequence information. Here, we utilized two engineered ZFPs (Stx2-268 and SEB-435) to detect the Shiga toxin (stx2) gene and the staphylococcal enterotoxin B (seb) gene present in foodborne pathogens, Escherichia coli O157 and Staphylococcus aureus, respectively. Engineered ZFPs are immobilized on a paramagnetic bead as a detection platform to efficiently isolate the target dsDNA-ZFP bound complex. The small paramagnetic beads provide a high surface area to volume ratio, allowing more ZFPs to be immobilized on the beads, which leads to increased target DNA detection. The fluorescence signal was measured upon ZFP binding to fluorophore-labeled target dsDNA. In this study, our system provided a detection limit of ≤ 60 fmol and demonstrated high specificity with multiplexing capability, suggesting a potential for development into a simple and reliable diagnostic for detecting multiple pathogens without target amplification.

Improvement in joint efficiency with high productivity and narrow weld formation in friction stir welding

High productivity, excellent joint strength and small weld bead make friction stir welding an emerging joining technique to join difficult to weld dissimilar aluminum alloys. Effect of rotational speed, traverse speed and shoulder diameter on the joint strength and elongation of the friction stir welded dissimilar aluminum alloys (AA7475-AA2219) is investigated. In addition, parameters are optimized to obtain joint with narrow weld bead and high joint efficiency using the entropy-weighted technique for order of preference by similarity to ideal solution method. Nine experiments are performed as per the L9 orthogonal array and mechanical properties of the welded joints are measured. Results of the study reveal that optimum values of ultimate tensile strength and percentage elongation are obtained at a rotational speed of 710 rev/min, welding speed of 250 mm/min and shoulder diameter of 10 mm resulting in good joint strength, high productivity and narrow weld bead. From the selected process parameter range, tool shoulder diameter is found to be the most significant parameter. The findings of the present study are discussed in light of the friction stir welding process mechanism, available literature, mechanical testing, microstructure and fractography.

Immobilization of active ammonia-oxidizing archaea in hydrogel beads

Ammonia-oxidizing archaea (AOA) are major players in the nitrogen cycle but their cultivation represents a major challenge due to their slow growth rate and limited tendency to form biofilms. In this study, AOA was embedded in small (~2.5 mm) and large (~4.7 mm) poly(vinyl alcohol) (PVA)—sodium alginate (SA) hydrogel beads cross-linked with four agents (calcium, barium, light, or sulfate) to compare the differences in activity, the diffusivity of nitrogen species (NH4+, NO2−, and NO3−), and polymer leakage in batch systems over time. Sulfate-bound PVA-SA beads were the most stable, releasing the lowest amount of polymer without shrinking. Diffusion coefficients were found to be 2 to 3 times higher in hydrogels than in granules, with ammonium diffusivity being ca. 35% greater than nitrite and nitrate. Despite a longer lag phase in small beads, embedded AOA sustained a high per volume rate of ammonia oxidation compatible with applications in research and wastewater treatment.

On the Tactics of Ab Initio Search for the Shape of Protein Particles from Small-Angle X-Ray Scattering Data

The determination of 3D particle shapes from the one-dimensional data on small-angle scattering from macromolecule solutions is ambiguous. In addition, due to the poor conditionality of the inverse problem, the determination is unstable and depends on the search algorithm parameters. Consequently, in practice, it is necessary not only to estimate the degree of stability of the solution of the problem but also to select the parameters of both the search method and the model itself. A search tactic is considered which consists in sequential determination of a set of models of particle shape represented in the form of a structure consisting of small close-packed spherical beads. The set of solutions is obtained by varying the relative contributions of objective function terms: the criterion for the deviation of the model scattering curve from the experimental one and the penalties for the looseness and discontinuity of the body structure, and the deviation of the average number of bead contacts from a specified value. Examples of the solution of model problems and the determination of molecular shape from the measurements available in the SASBDB bank of structures are presented.

Transpiration through hydrogels

We present experiments and theory relating to transpiration through unrestrained hydrogel beads in contact with a water reservoir below and air above. Experimentally, we find that saturated hydrogel beads shrink until a steady state is reached in which water flows continuously through the beads. The size of the bead in steady state is sensitive to the evaporation rate, which depends on the relative humidity and speed of the surrounding air, and to the pressure head imposed by the fluid reservoir. Specifically, the bead size decreases with increasing pressure head or evaporation rate. Our one-dimensional model proposes that transport in the hydrogel is driven by gradients in osmotic pressure, caused by gradients in polymer concentration in the hydrogel that correspond to gradients in swelling. If the evaporation rate or the pressure head changes, the adjustment of this gradient requires the bead to change shape and size. Smaller beads have larger gradients of osmotic pressure, which drive higher transpiration rates and can draw water against larger pressure heads.

Actuating water droplets on liquid infused surfaces: A rickshaw for droplets

An efficient actuation method for millimetric droplets is described: Single droplets are driven on a liquid infused surface by a small bead that acts as a carrier, like a rickshaw. When the bead is moved at a fixed velocity the droplet follows its trajectory, up to a critical value of the velocity at which the bead and the droplet lose contact. The critical velocity is predicted from a balance between the bead/droplet adhesion force and the friction acting on the droplet where it is in contact with the substrate.

An inexpensive, simple and effective method of genome DNA fragmentation for NGS libraries.

Next-generation sequencing (NGS)-library preparation for whole-genome sequencing (WGS) starts with DNA fragmentation, and sonication is a physical approach used most often due to its simplicity and reproducibility. However, the commercially available Covaris instrument has a high price for both the device and consumables. Here, we describe our in-house method of DNA shearing by sonication with small (100-600 µm) glass beads and an ultrasonic bath. The fragmentation conditions were optimized for the bacterial WGS with ∼550-bp fragment size (the ultrasonic bath water temperature 5-10°C, glass beads 0.06 g, the fragmentation time 50 s) and for human DNA with ∼250 bp (fragmentation with the same parameters for 4 min). Fragmentation results were compared with the Covaris instrument for preparing several bacterial NGS libraries for Illumina NGS platforms by several characteristics. We obtained close mean fragment lengths (523-623 versus 480-646), similar mono- and dinucleotide specificity of shearing, and comparable indicators of read alignment and de novo assembly for both methods. Thus, the described method is a new fast, and effective DNA fragmentation approach that can be used in different WGS applications.

Simple and portable on-site system for nucleic acid-based detection of Clostridium difficile in stool samples using two columns containing microbeads and loop-mediated isothermal amplification.

It is challenging to employ nucleic acid-based diagnostics for the in situ detection of Clostridium difficile from complex fecal samples because essential sample preparation and amplification procedures require various experimental resources. In this study, a simple and effective on-site nucleic acid-based detection system was used to detect C. difficile in stool samples. Two columns containing different microbeads, namely, glass and functionalized graphene oxide-coated microbeads, were designed to remove relatively large impurities by filtration and concentrate bacteria, including C. difficile, from stool samples by adsorption. The bacterial nucleic acids were effectively extracted using a small bead beater. The effectiveness of enzyme inhibitors remaining in the sample was efficiently reduced by the direct buffer developed in this study. This sample preparation kit consisting of two simple columns showed better performance in real-time polymerase chain reaction (PCR) and equivalent performance in loop-mediated isothermal amplification (LAMP) than other sample preparation kits, despite 90% simplification of the process. The amplification-ready samples were introduced into two microtubes containing LAMP pre-mixtures (one each for E. coli as an external positive control and C. difficile) by a simple sample loader, which was operated using a syringe. LAMP, which indicates amplification based on color change, was performed at 65 °C in a small water bath. The limit of detection (L.O.D) and analytical sensitivity/specificity of our simple and effective kit were compared with those of a commercial kit. C. difficile in stool samples could be detected within 1 h with 103 cfu/10 mg using LAMP combined simple on-site detection kit.

Transcatheter Arterial Chemoembolization with Drug-Eluting Beads for the Treatment of Hepatocellular Carcinoma: Recommended Selection for Small-Caliber (

Drug-eluting beads transarterial chemoembolization (DEB-TACE) is an alternative to conventional lipiodol-based TACE (cTACE) to treat hepatocellular carcinoma (HCC). With the advancement in pharmacology, small-caliber DEB-TACE (<100 μm) has been introduced since 2016. For the treatment of hepatic neoplasms or HCC, there is a tendency to use smaller beads by DEB-TACE to achieve more extensive tumor necrosis and a significant reduction in liver toxicity in comparison with that caused by cTACE. However, the indications and potential complications of small-caliber DEB-TACE remain uncertain and have not been well established, due to lack of randomized phase III clinical trials. Instead of systematic or meta-analysis review, this narrative review article describes the suggested indications and contraindications of DEB-TACE with small DEBs, benefit of super-selective embolization of the feeding arteries and the recommended selection of small-caliber DEB. This review was approved by the institutional review board (File Number: 1-105-05-158).

Fluidization behavior of graphitized glassy particles in a fluidized carbon bed cooling process for investment casting

Fluidized Carbon Bed Cooling (FCBC) is an innovative investment casting process for directional solidification of superalloy components. It takes advantage of a fluidized bed with a base of small glassy carbon beads for cooling and other low-density particles that form an insulating layer by floating to the bed surface. This so-called “Dynamic Baffle” protects the fluidized bed from the direct heat input from the high-temperature heating zone and provides the basis for an improved bed microstructure. The prerequisites for a stable casting process are stable fluidization conditions where neither collapse of the bed nor particle blow out at excessive bubble formation occur.This work aimed to investigate the fluidization behavior of spherical carbon bed material in argon and air at temperatures between 20 to 350 °C. Systematic studies at reduced pressures using the FCBC prototype device were performed to understand the stable fluidization conditions at all stages of the investment casting process. The particle shape factor and size distribution characterization and the measurement of the powder’s minimum fluidization velocity and bed voidage show that this material can be fully utilized as a cooling and buoyancy medium during the FCBC process.

Temperature-responsive spin column for sample preparation using an all-aqueous eluent

We present a temperature-responsive spin column using an all-aqueous eluent. The method is intended as a simple sample preparation method for protein removal from serum, which is required for serum drug analysis. As packing materials for the spin column, we prepared two types of silica beads via surface-initiated radical polymerization. The large beads (diameter, 40–63 μm) were grafted with a temperature-responsive cationic copolymer, poly(N-isopropylacrylamide-co-N,N-dimethylaminopropyl acrylamide-co-n-butyl methacrylate) (P(NIPAAm-co-DMAPAAm-co-BMA)), and the small beads (diameter, 5 μm) were grafted with a temperature-responsive hydrophobic copolymer, P(NIPAAm-co-BMA). The beads were packed into the spin column as a double layer: P(NIPAAm-co-BMA) silica beads on the bottom and P(NIPAAm-co-DMAPAAm-co-BMA) silica beads on the top. The sample purification efficacy of the prepared spin column was evaluated on a model sample analyte (the antifungal drug voriconazole mixed with blood serum proteins). At 40 °C, the serum proteins and voriconazole were adsorbed on the prepared spin column via hydrophobic and electrostatic interactions. When the temperature was decreased to 4 °C, the adsorbed voriconazole was eluted from the column with the pure water eluent, while the serum proteins remained in the column. This temperature-responsive spin column realizes sample preparation simply by changing the temperature.