Extraneous Particles Research Articles

Investigating the content of microplastics and other extraneous particles in Polish bottled water

Bottled water has enjoyed a global increase in popularity since it is generally perceived to be superior in quality to tap water and necessary when tap water is non-potable. As a result, ensuring that it meets the requisite quality standards is of vital importance. This work aims to examine the content of solid particles, including microplastics, in bottled water available in Polish stores. The second aspect is the preliminary determination of the influence of the water gassing process, together with thermal and light factors, on the content of particles in the water. The number of particles was counted by colour and shape, with the number ranging from 87 to 188 per litre of water; on average, there were 136 ±32 particles per litre of water, demonstrating that water from disposable plastic bottles is contaminated with various substances. The difference in the number of particles may be due to the origin of the waters, the processes they were subjected to prior to bottling, the properties of the bottles as packaging, and the conditions and length of storage and transport. Additional Fourier-transform infrared spectroscopy (FT-IR) analysis confirmed that about 75% of the particles were polymers, and 50% of them were plastics. Particularly alarming is the fact that the bottled waters mostly contained microplastic particles (MP) of smaller sizes, the kind which is recognized as being the most dangerous to human health. In the study, most particles were in the form of irregular shapes, which may indicate that they come from the destruction of waste or plastic products. This is also indicated by the domination of colourless particles. More particles were found in waters exposed to high and low temperatures than in waters stored at room temperature, potentially indicating that storage conditions for drinking water are important. Taking into account the results obtained, increasing attention should be paid to the health risks posed by such microplastics and there is a clear need to introduce legal regulations on the matter. The lack of any legal guidelines or unified standards in the field of MP research means that the results are not always representative, and it also makes it difficult to compare the results from different studies.

Nanoparticle Incorporation to Enhance Titanium Alloy Electric Discharge Machining Capabilities

The primary objective of this study was to examine the effects of the Powder-blended Micro Electric Discharge Machining (PMEDM) technique on micromachining applications, specifically when sea water is employed as the dielectric medium. Tiny apertures with a width of 200µm were punctured over Ti-6Al-4V plates. In the initial round of experimentation, the machining performance was evaluated by subjecting sea water to various process variables without the inclusion of any other ingredients. The effects of input variables, including electrode material, hole voltage, current, Pulse-on-time, and Duty factor, on the Material Removal Rate (MRR), Tool Wear Rate (TWR), Overcut (OC), Circularity Error (CE), and Taper Ratio (TR) were analysed by conducting tests in accordance with Taguchi's L18 plan design. The method employed to ascertain the optimal parametric configuration for multi-objective enhancement involved utilising the strategy of soliciting inclination based on similarity to an ideal arrangement. The present study aimed to investigate the effects of foreign materials on the dielectric-based miniature electrical discharge machining (EDM) process in sea water. This was achieved by utilising powders with varying weight concentrations and molecule sizes, including non-conductive (Al2O3), semi-conductive (SiC), and conductive (Al) powders. The experimental setup ensured that the variable boundaries were maintained at their ideal settings. The results indicate that the choice of tool has a notable influence on the functioning of micro EDM when sea water is employed as the dielectric, without the inclusion of extraneous particles. The performance metric of multi-objective execution in PMEDM is influenced by the conductivity of supplementary compounds. An 83.18 percent increase in Material Removal Rate (MRR) was observed when SiC added compounds were utilised in Powder Mixed Electrical Discharge Machining (PMEDM). Conversely, there was a drop in Tool Wear Rate (TWR) by 36.42 percent, Open Circuit voltage (OC) by 21.48 percent, Current Efficiency (CE) by 45.15 percent, and Tool Roughness (TR) by 22.87 percent.

WITHDRAWN: Novel machine learning models for flow imaging microscopy sub-visible particle classification in protein formulations

Understanding the particulate content of formulated drug products is essential for ensuring patient safety. In particular, it is critical to assess the presence of aggregated proteins or extraneous particles (e.g. fibres) that pose potential dangers. Additionally, it is useful to be able to distinguish non-proteinaceous particles, such as silicone oil droplets that commonly occur in formulations stored in pre-filled syringes. Standard particle counting methods (e.g. light obscuration) provide only total numbers of particles of a given size, but provide no mechanism for particle classification. Significant recent work has focused on the use of flow imaging microscopy to enable simultaneous classification and counting of particles using machine learning (ML) models including convolutional neural networks (CNN). In this paper we expand upon this theme by exploring techniques for achieving high prediction accuracy when the size of the labeled dataset used for model training is limited. We demonstrate that maximum performance can be achieved by combining multiple techniques such as data augmentation, transfer learning, and novel (to this field) models combining imaging and tabular data.

Collagen sponge scaffolds containing growth factors for the functional regeneration of tracheal epithelium

Tracheal epithelia have barrier and mucociliary clearance functions that prevent invasion of extraneous particles and infectious materials. Hence, following tracheal reconstructions, functional and morphological regeneration of epithelia is required to prevent respiratory declines and infectious diseases. Although growth factors (GFs) promote the regeneration of tracheal epithelial morphologies, it remains unclear whether tracheal grafts containing GFs are beneficial for regeneration of tracheal epithelial functions. Thus, we fabricated collagen sponge scaffolds containing insulin-like GF-1 (IGF-1) and the basic fibroblast, hepatocyte, and epidermal GFs (bFGFs, HGFs, and EGFs, respectively), and we evaluated the effects of the grafts on the functional regeneration of tracheal epithelia. Partial tracheal defects were imposed surgically, and collagen sponges containing IGF-1, bFGF, HGF, or EGF were then transplanted to defect sites. Subsequent immunofluorescence studies suggested that EGF and bFGF contribute to regular distributions of tight junction molecules, and tracer permeability assays suggested that EGF and bFGF promote regeneration of barrier function. Increased ciliogenesis was also observed using scanning electron microscopy in reconstructed regions treated with EGF- and bFGF-supplemented collagen sponges. However, bFGF-supplemented collagen sponges led to greater microsphere transport than did EGF-supplemented sponges. The present data suggested that collagen sponge scaffold containing bFGF promotes functional regeneration of tracheal epithelial tissues.

STUDY OF THE PHASES OF ACICULA (LAMELLAR) MORPHOLOGY IN THE MATERIAL OF TURBINE BLADES OF GAS TURBINE ENGINES

We present the results of studying features of separating phases of acicular (lamellar) morphology in the structure of blade material of operating gas turbine engines (GTD). A decrease in the strength characteristics and plasticity of the blade feather material in the zone of phase separation which contributes to in-service fatigue destruction of the turbine blade is revealed and illustrated with a specific example. Separation of the phases of needle (lamellar) morphology can be considered a criterion for the quality control of the structure and performance of the turbine blade material which requires appropriate rating. Difficulties in revealing the identification differences in the topologically close-packed (TCP) phases and carbides of Me6C type with acicular (lamellar) morphology are noted. A tend of a heat-resistant alloy to form σ-phase (i.e., the serviceability of the alloy) can be estimated in calculation of the chemical composition from the number of electron vacancies. At the same time, detection and rejection of the blades with inadmissible discharge of σ-phases can be done methods of direct non-destructive control. We develop a method of non-destructive electromagnetic control of TCP-phase (of σ-type) present in the structure of the material of highly oxidized blades (also with extraneous ferromagnetic particles present in internal cavities. Timely detection of σ-phases present in the structure of blade materials upon manufacture or repair will eliminate using the blades with reduced strength and plastic characteristics in GTE.

IMPURITY INDUCED WRINKLING PATTERNS IN METAL FILMS DEPOSITED ON SOFT ELASTIC SUBSTRATES

Metal (iron and nickel) films have been deposited on soft elastic polydimethylsiloxane (PDMS) substrates by direct current sputtering technique and the impurity induced wrinkling patterns are investigated by using optical microscopy and atomic force microscopy. It is found that the metal films can spontaneously form disordered wrinkles due to the isotropic compressive stress. In the vicinity of film impurities such as extraneous particles, linear defects, cracks and thickness-gradient film edges, the stress field becomes anisotropic owing to symmetry breaking and thus complex wrinkling patterns including straight stripes, herringbones, crossings, labyrinths and their transitions can be observed. The morphological evolutions, structural characteristics and physical mechanisms of the impurity induced wrinkles have been discussed and analyzed based on the continuum elastic theory.

A Unified CFD Based Approach to a Variety of Condensation Processes in a Viscous Turbulent Wet Steam Flow

A family of quasi linear mathematical models is presented and calculations made for viscous turbulent wet steam flow with a variety of condensation phenomena. These models can be applied to the analysis of equilibrium condensation, homogeneous (spontaneous) condensation, heterogeneous condensation on extraneous particles, and condensation of charged dispersed phase moving in an electrostatic field. The unified model is represented by coupled systems of gas dynamic equations for viscous turbulent two-phase flow, kinetic and electro-kinetic equations tracing out combined processes of size and charge growth, and electromagnetic field equations described an electric field with an account of self-induced in-part by a moving electrical cluster. The numerical procedure is time marching, monotone, implicit, of second order accuracy by space and time coordinates, and exhibits high resolution shock capturing ability. Viscous flow field calculations made with this procedure reveal significant influence on condensation by the shear boundary layers and wakes. Distributions of cooling rate, droplet radius and parameters of the bulk flow are predicted. Verification of the codes against known experimental data is presented.

Semi-Quantitative Analysis of Inherent Visible Particles for Biopharmaceutical Products

Visible particles must be monitored as part of the control strategy for parenteral biopharmaceutical drug products. In these products, formation of protein particles is a natural occurrence. All protein drugs contain particles that vary greatly in visibility and size from invisible (sub-micron) to visible (millimeter), and pharmaceutical companies are required to monitor and minimize the presence of visible and sub-visible particles in their products. There is an industry-wide unmet need for particle standards for visual inspection of protein drugs. A new, semi-quantitative method using particle standards for assessing the levels of small, naturally occurring visible particles is presented. This method can be used during drug development to identify a formulation that minimizes particle formation and also during testing of final clinical or commercial drug product to monitor and control naturally occurring proteinaceous visible particles.

Characterization of mineral matter particles in gasification and combustion processes

Slagging and fouling mechanisms in high temperature solid fuel conversion processes are usually related to the presence of mineral components in the fuel. These mineral components can be extraneous particles or organically bound to the fuel. Both types will be released during the combustion or gasification process. The released mineral particles are diverse and can undergo certain transformation mechanisms along the flue gas path. Common fuel investigation methods rely on bulk ash analysis and other methods that do not take into account the process parameters. It is difficult to predict the deposition and also corrosion behavior of a certain fuel with these laboratory methods alone. An approach with more information about the actual particle situation and where the actual process parameters can be reproduced would be preferable.One way to make the released mineral particles visible, depending on temperature and concentration, is the so called Particle-Wire-Mesh method. Flue gas is extracted from the process through a wire-mesh formed by twilled Dutch weave. The twilled Dutch weave serves as a filter, i.e. particles that are contained in the flue gas will deposit in the pockets or on the wires of the weave.This weave also serves as the sample holder for SEM and EDS analyses. With these analyses the particles can be made visible in the same form as they are extracted from the process. The particles can then be characterized in terms of size, shape, and elemental composition. Size and shape give information about whether the particle has possibly been fused during the combustion process (spherical particles) or not (regularly shaped particles with sharp edges). The location where a particle is found on the wire-mesh can typically be either the wire itself or the pocket. It indicates whether the particle has a probability to stick on furnace walls and heat exchanger surfaces and form a deposit. In order to be found on the wires a particle has to have a sticky surface or impact at a surface that is sticky itself. Particles that are found in the pockets are not sticky.The Particle-Wire-Mesh method of collecting particle samples gives the opportunity to characterize a certain fuel toward the behavior of its mineral content. The metal weave makes it possible to differentiate between single particles. Together with extracting particle samples at different locations in the process, to get the influence of different temperatures, this results in a detailed image of the different species contained in the mineral matter of the fuel.

Ancient DNA analysis of dental calculus

Dental calculus (calcified tartar or plaque) is today widespread on modern human teeth around the world. A combination of soft starchy foods, changing acidity of the oral environment, genetic pre-disposition, and the absence of dental hygiene all lead to the build-up of microorganisms and food debris on the tooth crown, which eventually calcifies through a complex process of mineralisation. Millions of oral microbes are trapped and preserved within this mineralised matrix, including pathogens associated with the oral cavity and airways, masticated food debris, and other types of extraneous particles that enter the mouth. As a result, archaeologists and anthropologists are increasingly using ancient human dental calculus to explore broad aspects of past human diet and health. Most recently, high-throughput DNA sequencing of ancient dental calculus has provided valuable insights into the evolution of the oral microbiome and shed new light on the impacts of some of the major biocultural transitions on human health throughout history and prehistory. Here, we provide a brief historical overview of archaeological dental calculus research, and discuss the current approaches to ancient DNA sampling and sequencing. Novel applications of ancient DNA from dental calculus are discussed, highlighting the considerable scope of this new research field for evolutionary biology and modern medicine.

Discovery and anatomy of the arenophilic system of cuspidariid clams (Bivalvia: Anomalodesmata)

The arenophilic system of anomalodesmatan clams comprises multicellular glands, muscular papillae, and radial lines of adhesive secretion, which glue sand grains and other extraneous particles to the external surface of the shell. The presence and morphology of these organs have been established in an increasing number of taxa, but arenophilic glands were not previously known to occur in the deep-sea, carnivorous family Cuspidariidae. Dissections, histological sections and ultrastructural examination of members of the cuspidariid genera Cuspidaria and Cardiomya revealed a functional arenophilic system positioned around the siphonal apparatus. Glands are contained in muscular papillae at the posterior tip of the siphonal sheath, from where they deposit their adhesive secretion onto the shell rostrum. Discovery of an arenophilic system in cuspidariid clams adds support to the idea that the glands are a synapomorphy of Anomalodesmata, secondarily absent in only one of the major component branches (the clade joining Thraciidae, Cleidothaeridae, and Myochamidae). Moreover, similarity between the arenophilic papillae we observed on the siphonal sheath of Cuspidaria, Cardiomya, and Myonera, and literature reports on the crown of tentacles of Multitentacula is puzzling and highlights the need for further studies of the latter genus.

Synthesis and characterization of single-crystal CdS nanosheet for high-speed photodetection

One-dimensional nanostructures have several unique advantages over bulk material and thin films, which can be exploited for high-speed photodetection. Furthermore, as bulk CdS has a high photosensitivity and quantum efficiency, there is considerable potential for the use of CdS nanostructures in advanced devices. In this study, single-crystal CdS nanosheets were grown by thermal evaporation and fully characterized to determine their potential for application in high-speed photodetectors. A high-quality nanosheet was confirmed to have a smooth surface with no extraneous particles and a strong orientation to the (110) plane of the wurtzite (hexagonal) phase of CdS. The Cd/S ratio was found to be nearly stoichiometric at 1.09. Photoluminescence measurement of a single-crystal CdS nanosheet showed a high emission intensity at a wavelength of 493nm. The current–voltage characteristics of the CdS nanosheet on Al thin film indicated an Ohmic contact in dark and under illumination by ambient, 365-nm, 405-nm, and 460-nm light. The light responsivity showed a peak at 460nm. Under 365-nm, 405-nm, and 460-nm chopped light, at a bias voltage of 1, 3, and 5V, the photocurrent rise and decay times were investigated. The device showed faster response times for 460-nm light. This fast response was attributed to the high quality of the single crystal, the absence of defect states, and the high surface/volume ratio. The device showed a high quantum efficiency of 22.3×103% when it was illuminated by 365-nm light under a bias of 5V; this efficiency increased to 36.3×103% and 40.5×103% when the device was illuminated by 405-nm and 460-nm light, respectively.

LED와 CMOS 이미지 센서 기반 간 기능 분석용 소형 광학장치

This paper presents a portable and compact optical device which can conveniently be used to perform a functional analysis of human liver function. The proposed system employed red/green LEDs, as a light source, and CMOS image sensor, which is commonly used in cellular phones. With this system, several blood serum samples have been evaluated for liver functional analysis by measuring light absorption level through the blood serum samples depending on aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin concentration. The light absorption through the blood serum samples containing AST, ALT, or total bilirubin can provide their concentrations. The green light absorption is more sensitive to the concentration of AST or ALT, and the red light absorption is more sensitive to the total bilirubuin concentration. Additional calibration steps were performed by using a MATLAB program in order to eliminate the light scattering effects from the extraneous particles existing in each blood serum sample. From the blind test, three standard light intensity curves through each enzyme have been obtained and the enzyme concentration values have been compared to those obtained from a commercially available biochemistry analyzer (Toshiba 200 FR). The average percent difference in the obtained concentrations from two systems for AST, ALT, and total bilirubin concentration came out to be 7.79%, 7.98%. and 7.56%, respectively, with the adjusted coefficient of determination (R2) higher than 0.98. This system can possibly lead to a low-cost and simple system that can be used as a point-of-care (POC) system in a condition without advanced equipments.

The morphology of gills of Haliotis tuberculata (Linnaeus, 1758)

AbstractManganaro, M., Laurà, R., Guerrera, M.C., Lanteri, G., Zaccone, D. and Marino, F. 2011. The morphology of gills of Haliotis tuberculata (Linnaeus, 1758). —Acta Zoologica (Stockholm) 93: 436–443.Although the morphology of abalone gills has been studied by some authors, up to date no data are available about the gills of Haliotis tuberculata. This study was carried out, by light and electron microscopy, on 10 wild adult H. tuberculata. Gills lamellae produce an undulated surface increasing the area in contact with water. At the level of skeletal rods, we observed a joint‐like structure that allows a checked movement. The left ctenidium is always decidedly larger than the right, probably because of the enormous size of the shell muscle. The cilia permit oxygenated water that leaves the afferent border and is thrust away at the tips of the lamellae by the extremely long cilia. Ciliary movement may take part in sweeping mucous secretions to capture extraneous particles and remove them from the gills. Three types of mucous cells are distributed along the epithelium of the afferent and efferent zones of the gill filament. They seem to play a role in the cleansing of gills in coordination with the muscle contraction and ciliary movement. The presence of microvilli on particular cells reflects their role associated with the absorption of substances from the environment. A haemolymphatic vessel is located in the central zone of the gill filament. The backbone of the haemolymphatic vessel is a chitino‐like structure, which gives support to the gills.

Contribution of the light filth method to the Integrated Pest Management of a flour mill

An important contribution to Integrated Pest Management in stored-product protection can be provided by the light-filth method since it gives particular attention to the extraneous particles contaminating food (such as insects, insect fragments, mites, hairs, feather barbules, etc.), extending to the identification of the material from which they have originated or the animals and vegetables from which they derive or have been part of in the past. In this regard, semolina produced by an industrial mill (processing 500 t of durum wheat per day) located in South Italy was examined for light filth according to the method established by Italian regulation. During the investigations we verified the presence of insect fragments in 250 semolina samples collected from June 2008 to July 2009. Our results show that the number of insect fragments found in the samples (from 0 to 15 fragments per 50 g semolina) remained below the limit of 75 fragments per 50 g flour established by the Italian regulation. The fragments of arthropods found in the semolina samples had different origins. Numerous fragments came from both immature and adult insects infesting plants of wheat in fields (thrips and aphids); many other fragments belong to internal feeding insects and external feeding insects ( Sitophilus spp., Rhyzopertha dominica, Tribolium spp., Cryptolestes spp., Oryzaephilus spp., and Nemapogon granellus ) which are able to infest cereals during post-harvest processing or to colonize millrooms in which dusts, cereal debris, and flour residues are present. We also found fragments associable to structural pests like flies and psocids that are present in environments contaminated by mould spores and fungal hyphae. The results revealed that the fumigation of the mill realized in August 2008 did not modify the number of fragments contaminating the semolina, which remained at the same level during the 14 months of the experiment. Keywords : Light filth, Semolina, IPM, Flour mill, Italy.

Structural features of eggs of the basal phasmatodean Timema monikensis Vickery & Sandoval, 1998 (Insecta: Phasmatodea: Timematidae)

Structural features of the eggs of a basal phasmatodean, Timema monikensis Vickery & Sandoval, 1998 (Timematidae) were examined. The eggs of this species are soft and deposited coated with soil and/or other extraneous particles. The chorion, which is transparent and weakly sclerotized, is composed of an endochorion and an exochorion. The non-inclined operculum is located at the anterior pole of the egg. The chorion in the marginal region of the operculum is thinned to form an opercular collar together with the chorion of the egg body. An inverted triangular micropylar plate is on the ventral side of the egg attached to the opercular collar. The micropylar plate is without external differentiations but is specialized inside the chorion. A single micropyle, with a simple funnel-shaped chorionic opening, occurs on either side of the micropylar plate. The posterior mound, located at the posterior pole, is a thickened chorion rich in fine vertical striations, and the serosal cuticle beneath is thickened and highly specialized. The eggs of Timematidae were characterized and compared with those of Euphasmatodea and Embioptera. A phylogenetic discussion is presented, strongly supporting the assemblage of Timematodea, Euphasmatodea and Embioptera as monophyletic.

Occlusal microwear texture analysis and the diets of historical/prehistoric hunter‐gatherers

AbstractWith the exception of few studies, occlusal microwear of pre‐agricultural modern humans has not been documented. In this study, microwear fabrics of samples from seven historic/prehistoric hunter‐gatherer populations with known and diverse dietary habits, representing mostly meat‐eaters from different environments, arctic/tundra (Tigara from Point Hope), cold‐steppe (Fuegians) and Mediterranean (Chumash), and mixed‐diet hunter‐gatherers from tropical climates (Andamanese and Khoe‐San from Matjes River, Riet River, and Oakhurst Shelter), were analysed to better understand how dietary differences affect microwear in these groups and to establish a reasonable comparative database for interpreting fossil hominins microwear.Significant microwear differences, related to diet and food preparation techniques, between the meat‐eaters and mixed‐diet hunter‐gatherers were detected. Finer scale differences within each of these dietary categories were also observed. Ethnographic accounts indicate that the Tigara and Andamanese ingested hard particles attached to their food as a result of their food preparation techniques; their microwear fabrics also reflect highly abrasive diets. On the other hand, as expected, the microwear signatures of the Chumash and Fuegians indicate a diet low in abrasives, reflecting their almost exclusive reliance on marine meat for subsistence and the low amounts of extraneous particles attached to this meat. The mixed‐diet Khoe‐San occupy an intermediate position between the Tigara and Andamanese on the one hand, and the Chumash and Fuegians on the other, with regard to the level of abrasives ingested. The Khoe‐San ate large amounts of hard plants, most likely responsible for abrading their enamel surface. Copyright © 2008 John Wiley & Sons, Ltd.

Particulatization of gas–solids fluidization

Several theories and methods for particulatization of aggregative fluidization have been proposed, including particle design (size, density, shape, surface structure, extraneous particles), external force field design (axial uniform magnetic field, transverse rotating magnetic field), reactor internals and configuration design (ring-shaped internals, fan-shaped internals, floating balls, internal and external circulating fluidizing beds), and fluid design (density, viscosity, supercritical CO 2). Experimental results showed that the above theories and methods have been effective in restraining or suppressing the formation of bubbles and agglomerates, and in changing gas–solids fluidization from aggregative to particulate. In addition, methods and indices for evaluating the quality of fluidization have been established, and several instruments have been developed.

“Verso” laser cleaning of mechanically thin films

In usual dry laser cleaning of opaque samples, short laser pulses are projected onto the sample surface to be cleaned. Energy transferred from light ejects extraneous particles away from the surface. Laser beam fluence is limited by the damage reached by high temperature that the sample surface can produce. We have experimentally shown that for thin samples, the thermo-elastic wave propagates within the whole sample thickness, thus also the rear surface, while temperature effects are limited to the front surface. Therefore, the proposed “verso” laser cleaning technique (the pulsed laser beam impinges on rear sample surface) can be applied to any opaque “mechanically thin” film and is useful for samples having delicate treatments on the surface to be cleaned (e.g. written paper, painted tiles, magnetic films). We have applied our technique to paper sheets showing that it is possible to efficiently clean the surface without damaging ink marks on it. Using a probe beam deflection (PBD) technique in both direct and reverse configuration we have shown that the “verso” cleaning effect is due to the higher penetration depth of the thermo-elastic wave with respect to the temperature profile propagation.

Redistribution of Extraneous Solid Particles Suspended in Molten Metal during Passage of an Electric Current

Redistribution of nickel-base heat-resistant alloy suspended in molten tin under the action of a direct electric current is studied by experiment and analyzed. It is established that there is an increase in solid particle concentration over the height and in the radial direction under the action of a current passing along the container axis. This is explained by the simultaneous effect of thermal convection and Lorentz contraction electromagnetic forces directed radially.