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Purpose: The aim of the present study was to compare the histomorphometrically evaluated new bone formation (NB), the radiographically measured graft stability, and the clinical implant outcome for maxillary sinus augmentation grafted with deproteinized bovine bone mineral (DBBM) with either small (Bio-Oss-S, Geistlich) or large (Bio-Oss-L, Geistlich) particles. Materials and Methods: Using a split-mouth study design, bilateral maxillary sinus augmentation was performed in 13 patients either with Bio-Oss-S particles (0.25 to 1 mm) or Bio-Oss-L particles (1 to 2 mm). After a healing period of 6 months, bone biopsies were axially retrieved in the molar region for histologic/histomorphometric analysis of NB, including subsequent staged implant placement. To determine graft stability, the maxillary sinus augmentation vertical graft heights were radiographically measured immediately after sinus augmentation, at implant placement, and at the 2- and 4-year post-augmentation follow-ups. In addition, the clinical implant-prosthodontic outcome (survival/success/marginal bone loss) was assessed at 1 and 3 years post-loading. Results: A total of 22 sinuses from 11 patients with split-mouth evaluation were ultimately available for data and statistical analysis. Histomorphometric analysis of the axially retrieved bone biopsies revealed the presence of NB (S: 25.5% ± 7.0% vs L: 23.6% ± 11.9%; P = .640), residual graft particles (S: 19.6% ± 9.2% vs L: 17.5% ± 6.3%; P = .365) as well as connective tissue (S: 54.9% ± 9.2% vs L: 58.9% ± 12.5%; P = .283), without significant differences between the use of small (Bio-Oss-S) and large (Bio-Oss-L) particles. However, there was significantly (P = .021) higher bone-to-graft contact (BGC) for the small-particle graft sites (27.9% ± 14.8%) compared to the large-particle graft sites (19.9% ± 12.9%), representing a significantly higher osteoconductivity. Both particle sizes showed significant (P < .01) vertical graft height reduction over time (4 years) of about 10%, with predominant graft reduction in the time period between sinus augmentation and implant placement compared to any follow-up periods after implant placement. At the 3-year post-loading implant evaluation, all implants and prostheses survived (100%), and the peri-implant marginal bone loss (S: 0.52 ± 0.19 mm; L: 0.48 ± 0.15 mm) as well as the peri-implant health conditions (S: 87.5%, L:81.2%) did not differ between implants inserted with the two different xenograft particles used. Conclusions: The use of small and large bovine xenograft particles for maxillary sinus augmentation provides for comparable bone formation, ensuring stable graft dimensions combined with high implant success and healthy peri-implant conditions. However, small particle size resulted in a higher BGC, providing for higher osteoconductivity than with the larger particle size. [ABSTRACT FROM AUTHOR]

Boron doped MoSi 2 particles have been envisioned as sacrificial particles for self-healing thermal barrier coatings (TBCs) but their oxidation behaviour is yet not well understood. In this work, oxidation of MoSi 2 based particle is studied in the temperature range of 1050–1200 °C. The oxidation proceeds from a transient to a steady-state oxidation stage. The kinetics during steady-state oxidation is captured with a thermal diffusion-based model. As compared to the oxidation of pure MoSi 2 particles, the addition of boron strongly enhances the silica formation. Also, a finer dispersion of MoB x in the MoSi 2 matrix accelerates the formation of silica. The oxide growth rate constant increases proportional with the boron content of the MoSi 2 particles. This enhanced oxidation is related to the microstructure of the oxide scale. Upon oxidation, boron yields B 2 O 3 , which promptly merge with SiO 2 to form amorphous borosilicate, hindering the formation of crystalline SiO 2. Consequently, the migration of oxygen in the borosilicate oxide scale is faster than in the silica oxide scale on pure MoSi 2 particles. [ABSTRACT FROM AUTHOR]

There has been great interest in developing high‐performance, sustainable and eco‐friendly materials. This study presents an innovative development and research of the mechanical properties of dog bone–reinforced epoxy composites to determine their suitability for biomedical applications. Good surface compatibility for the matrix and reinforcement was the target, complementing the structural compatibility needed for such applications. Hand‐lay open mould technique was used to fabricate the composites with varying weight percentage of dog bone particles (DBPs), and mechanical properties (tensile strength, Young's modulus, percentage elongation and flexural strength) were determined. The results show that the developed composites' mechanical properties were enhanced, and the tensile strength of 21.10 MPa–27.97 MPa, Young's modulus of 1531.00 MPa–1732.90 MPa, ductility of 2.10%–2.60% and flexural strength of 27.53 MPa–35.67 MPa were recorded for the biocomposites. Energy‐dispersive X‐ray spectroscopy (EDS) revealed the main elements' contents of the DBPs as calcium (50.3%), carbon (20.77%) and oxygen (11.76%). Scanning electron microscopy (SEM) examination of the fractured surfaces revealed the homogeneous distribution of the dog bone particulates within the epoxy matrix, which caused the property enhancement. The findings of this research underline the potency of processed animal waste as filler materials. [ABSTRACT FROM AUTHOR]

The present study addresses advanced monitoring techniques for particles and airborne molecular contaminants (AMCs) in cleanroom environments, which are crucial for ensuring the integrity of semiconductor manufacturing processes. We focus on quantifying particle levels and a representative AMC, hydrogen chloride (HCl), having known detrimental effects on equipment longevity, product yield, and human health. We have developed a compact laser sensor based on open-path cavity ring-down spectroscopy (CRDS) using a 1742 nm near-infrared diode laser source. The sensor enables the high-sensitivity detection of HCl through absorption by the 2-0 vibrational band with an Allan deviation of 0.15 parts per billion (ppb) over 15 min. For quantifying particle number concentrations, we examine various detection methods based on statistical analyses of Mie scattering-induced ring-down time fluctuations. We find that the ring-down distributions' 3rd and 4th standard moments allow particle detection at densities as low as ~105 m−3 (diameter > 1 μm). These findings provide a basis for the future development of compact cleanroom monitoring instrumentation for wafer-level monitoring for both AMC and particles, including mobile platforms. [ABSTRACT FROM AUTHOR]

This paper addresses the computational modeling of selective laser sintering (SLS) and 3D concrete printing (3DCP) processes in advanced manufacturing. We focus on the phenomena experienced by their feedstock materials at the level of their mesoscale (the sintering powder grain and concrete aggregate scales) during the manufacturing process. Our approach is based on the discrete element method (DEM) for representing the material's mechanical behavior. In SLS, the DEM is then combined with a lumped heat transfer model for describing the powder particles' thermal states when scanned by the laser beam. In 3DCP, in turn, the DEM is combined with the so-called discrete fresh concrete (DFC) model for representing the fresh concrete paste rheology. We then present a simple numerical solution scheme followed by numerical simulations on two model-problems, with which we illustrate the applicability of such modeling approach. [ABSTRACT FROM AUTHOR]

In this research, the finite-element numerical software COMSOL Multiphysics is used to simulate the electric pulse rock-breaking process, and the novel numerical model takes into account the multiple fields of electrical, thermal, and mechanical physics. The electric field strength inside the rock under the action of the electric pulse is updated by the full coupling function of COMSOL (version 6.1) software, and the electric damage variable χ is used to describe the process of electric breakdown inside the rock, to simulate the formation of plasma channel in the process of electric pulse rock-breaking. The voltage change curves and plasma channel trajectories in the electric breakdown process of the model in this paper are compared with the literature to verify the accuracy of the model. The formation process of plasma channels captures the temperature and stress changes during the whole process of electric pulse rock-breaking, to reveal the mechanism of the electric pulse rock-breaking process. With the presence of conductive particles inside the rock, the particles can effectively promote the formation of plasma channels, increase the area of electrical damage, and improve rock-breaking efficiency. Before the formation of the plasma channel, the internal temperature of the rock is about 600 K, and the stress is about 10−2 MPa; when the channel is formed, the energy of the electric pulse is mainly concentrated in the plasma channel, and the temperature of the plasma channel rises to 104 K. When the maximum stress exceeds the critical stress of the rock, the rock undergoes fracture. Furthermore, an appropriate increase in the rise time of the electric pulse increases the speed and area of rock-breaking, subsequently improving the efficiency of rock fracture. The results of the numerical modeling in this paper help to better understand the mechanism of the electric pulse rock-breaking process, which is of great engineering significance for the development of new electric pulse rock-breaking technology in the realm of geotechnical engineering. [ABSTRACT FROM AUTHOR]

BACKGROUND: High-flow nasal cannula (HFNC) systems employ different methods to provide aerosol to patients. This study compared delivery efficiency, particle size, and regional deposition of aerosolized bronchodilators during HFNC in neonatal, pediatric, and adult upper-airway and lung models between a proximal aerosol adapter and distal aerosol circuit chamber. METHODS: A filter was connected to the upper airway to a spontaneously breathing lung model. Albuterol was nebulized using the aerosol adapter and circuit at different clinical flow settings. The aerosol mass deposited in the upper airway and lung was quantified. Particle size was measured with a laser diffractometer. Regional deposition was assessed with a gamma camera at each nebulizer location and patient model with minimum flow settings. RESULTS: Inhaled lung doses ranged from 0.2-0.8% for neonates, 0.2-2.2% for the small child, and 0.5-5.2% for the adult models. Neonatal inhaled lung doses were not different between the aerosol circuit and adapter, but the aerosol circuit showed marginally greater lung doses in the pediatric and adult patient models. Impacted aerosols and condensation in the non-heated HFNC and aerosol delivery components contributed to the dispersion of coarse liquid droplets, high deposition (11-44%), and occlusion of the supine neonatal upper airway. In contrast, the upright pediatric and adult upper-airway models had minimal deposition (0.3-7.0%) and high fugitive losses (~24%) from liquid droplets leaking out of the nose. The high impactive losses in the aerosol adapter (56%) were better contained than in the aerosol circuit, resulting in less cannula sputter (5% vs 22%), fewer fugitive losses (18% vs 24%), and smaller inhaled aerosols (5 µm vs 13 µm). CONCLUSIONS: The inhaled lung dose was low (1-5%) during HFNC. Approaches that streamline aerosol delivery are needed to provide safe and effective therapy to patients receiving aerosolized medications with this HFNC system. [ABSTRACT FROM AUTHOR]

Background: This study aimed to explore the effects of the titanium dioxide (TiO2) concentration and particle size in hydrogen peroxide (HP) on tooth bleaching effectiveness and enamel surface properties. Methods: TiO2 at different concentrations and particle sizes was incorporated into 40% HP gel to form an HP/TiO2 gel. The specimens were randomly divided into 8 groups: C1P20: HP + 1% TiO2 (20 nm); C3P20: HP + 3% TiO2 (20 nm); C5P20: HP + 5% TiO2 (20 nm); C1P100: HP + 1% TiO2 (100 nm); C3P100: HP + 3% TiO2 (100 nm); C5P100: HP + 5% TiO2 (100 nm); C0: HP with LED; and C0-woL: HP without LED. Bleaching was conducted over 2 sessions, each lasting 40 min with a 7-day interval. The color differences (ΔE00), whiteness index for dentistry (WID), surface microhardness, roughness, microstructure, and composition were assessed. Results: The concentration and particle size of TiO2 significantly affected ΔE00 and ΔWID values, with the C1P100 group showing the greatest ΔE00 values and C1P100, C3P100, and C5P100 groups showing the greatest ΔWID values (p < 0.05). No significant changes were observed in surface microhardness, roughness, microstructure or composition (p > 0.05). Conclusions: Incorporating 1% TiO2 with a particle size of 100 nm into HP constitutes an effective bleaching strategy to achieve desirable outcomes. [ABSTRACT FROM AUTHOR]

Direct-on-Filter (DoF) analysis of respirable crystalline silica (RCS) by Fourier Transform Infrared (FTIR) spectroscopy is a useful tool for assessing exposure risks. With the RCS exposure limits becoming lower, it is important to characterize and reduce measurement uncertainties. This study systematically evaluated two filter types (i.e., polyvinyl chloride [PVC] and polytetrafluoroethylene [PTFE]) for RCS measurements by DoF FTIR spectroscopy, including the filter-to-filter and day-to-day variability of blank filter FTIR reference spectra, particle deposition patterns, filtration efficiencies, and pressure drops. For PVC filters sampled at a flow rate of 2.5 L/min for 8 h, the RCS limit of detection (LOD) was 7.4 μg/m3 when a designated laboratory reference filter was used to correct the absorption by the filter media. When the spectrum of the pre-sample filter (blank filter before dust sampling) was used for correction, the LOD could be up to 5.9 μg/m3. The PVC absorption increased linearly with reference filter mass, providing a means to correct the absorption differences between the pre-sample and reference filters. For PTFE, the LODs were 12 and 1.2 μg/m3 when a designated laboratory blank or the pre-sample filter spectrum was used for blank correction, respectively, indicating that using the pre-sample blank spectrum will reduce RCS quantification uncertainty. Both filter types exhibited a consistent radially symmetric deposition pattern when particles were collected using 3-piece cassettes, indicating that RCS can be quantified from a single measurement at the filter center. The most penetrating aerodynamic diameters were around 0.1 µm with filtration efficiencies ≥ 98.8% across the measured particle size range with low-pressure drops (0.2–0.3 kPa) at a flow rate of 2.5 L/min. This study concludes that either the PVC or the PTFE filters are suitable for RCS analysis by DoF FTIR, but proper methods are needed to account for the variability of blank absorption among different filters. [ABSTRACT FROM AUTHOR]

The present study was aimed at preparing stable dry adsorbed nanoparticles (DANs) of olanzapine (OLZ) loaded solid lipid nanoparticles (SLNs) for sustained release. OLZ SLNs were prepared by hot melt emulsification and ultrasonication using Precirol ATO 5 (PRE) as a solid lipid, combination of Kolliphor ELP (KELP) and Tween 80 (T80) as surfactants, after optimising formulation and process variables. The SLN system was subjected to evaluation of particle size, zeta potential, entrapment efficiency (EE), in-vitro drug release and ex-vivo intestinal permeability studies using the chicken intestinal segments (jejunum). Further, these SLNs were converted into stable DANs by adsorbing onto a Neusilin US2 (NUS2) and Avicel CL 611 (ACL) carriers using the granulation-evaporative drying method. The DANs were characterised for redispersion properties, in-vitro drug release, thermal behaviour, crystallinity, and morphology. The SLN and DAN had a particle size of 238.0 nm [0.274 polydispersity index (PdI)] and 302.4 [0.494 PdI] respectively. The zeta potentials of SLN and DAN were found to be −29.3 mV and −26.3 mV, respectively. The SLN had 67% EE, and showed a sustained drug release in various media. The highest permeability of SLNs was observed in ex-vivo permeation model compared to the OLZ suspension, indicating that SLNs have the potential to bypass hepatic metabolism. The adsorption of SLNs onto carriers was confirmed by surface morphology. The DAN had good flow properties and sustained drug release similar to that of SLNs. The X-ray diffraction (XRD) patterns and endothermic peaks confirmed the complete encapsulation of actives in lipid matrices. The encapsulating of OLZ in SLNs and converting it into DAN showed a sustained release and adsorption technique that can be used for improving the stability of NLC dispersion. The DANs can be offered in dosage forms such as filling into sachets, capsules and compressed into tablets. [ABSTRACT FROM AUTHOR]

Foods containing bits and pieces are often less liked by children; however, there is a limited understanding of how perceptions and preferences for foods with particles change during childhood. This study aimed to investigate preferences and perceptions of particle‐containing foods in children aged 5–12 years. Children (n = 485) completed a forced‐choice questionnaire on drawings of six pairs of foods, each available with or without particles. Additionally, children tasted yogurts added with muesli differing in particle size (median diameter: 3.9 or 7.5 mm) and evaluated their perception of particle size in mouth and their liking. The questionnaire results showed that children had a clear preference for foods without particles. The average probability of choosing the 'with‐particle' foods was 28%, significantly below the midpoint of 50% (p <.0001). Preferences for particle‐containing foods were lowest at age six and increased significantly with age (p =.0007). In the taste test, muesli particle size affected oral size perception (p <.0001) but not liking (p =.60). Older children were better able to differentiate particle size than younger children. However, there was no relationship between individual preferences for particle‐containing foods and oral size perception of muesli particles. The observation that children's texture preferences changed with age highlights the role of increased experience in shaping preferences for foods with particles. [ABSTRACT FROM AUTHOR]

Tunnel boring machines (TBMs) are used to excavate tunnels in a manner where the rock is constantly penetrated with rotating cutter heads. Fine particles of the rock minerals are thereby generated. Workers on and in the vicinity of the TBM are exposed to particulate matter (PM) consisting of bedrock minerals including α-quartz. Exposure to respirable α-quartz remains a concern because of the respiratory diseases associated with this exposure. The particle size distribution of PM and α-quartz is of special importance because of its influence on adverse health effects, monitoring and control strategies as well as accurate quantification of α-quartz concentrations. The major aim of our study was therefore to investigate the particle size distribution of airborne PM and α-quartz generated during tunnel excavation using TBMs in an area dominated by gneiss, a metamorphic type of rock. Sioutas cascade impactors were used to collect personal samples on 3 separate days. The impactor fractionates the dust in 5 size fractions, from 10 µm down to below 0.25 µm. The filters were weighted, and the α-quartz concentrations were quantified using X-ray diffraction (XRD) analysis and the NIOSH 7500 method on the 5 size fractions. Other minerals were determined using Rietveld refinement XRD analysis. The size and elemental composition of individual particles were investigated by scanning electron microscopy. The majority of PM mass was collected on the first 3 stages (aerodynamic diameter = 10 to 0.5 µm) of the Sioutas cascade impactor. No observable differences were found for the size distribution of the collected PM and α-quartz for the 3 sampling days nor the various work tasks. However, the α-quartz proportion varied for the 3 sampling days demonstrating a dependence on geology. The collected α-quartz consisted of more particles with sizes below 1 µm than the calibration material, which most likely affected the accuracy of the measured respirable α-quartz concentrations. This potential systematic error is important to keep in mind when analyzing α-quartz from occupational samples. Knowledge of the particle size distribution is also important for control measures, which should target particle sizes that efficiently capture the respirable α-quartz concentration. [ABSTRACT FROM AUTHOR]

Abstract—Gadolinium molybdate powder is produced by a mechanochemical method from a stoichiometric mixture of molybdenum oxide and dysprosium oxide. Using the XRF, TEM, and SEM methods, it has been shown that, during mechanochemical treatment for 30 min, owing to the occurrence of mechanochemical reactions between the initial powders, a fine powder of the Dy2MoO6 compound is formed, containing up to 8% Dy2(MoO4)3. The technological properties (fluidity, compactibility) of mechanically synthesized dysprosium molybdate powder, as well as its microstructure after sintering, have been studied. [ABSTRACT FROM AUTHOR]

Adsorption performances of one pollutant on different adsorbents likely depend on the adsorbent microstructures heavily. Hereon, zeolite, diatomite and kaolinite particles were selected as inexpensive adsorbents in this study with 2,4,6-trinitrotoluene (TNT) as an organic pollutant for the batch test to verify the effect of adsorbent microstructure on TNT adsorption performance. The results of kinetic, adsorption isothermic, and thermodynamic analyses indicated that the adsorption process of TNT on three particles is controlled by chemisorption, and that both are non-spontaneous entropic endothermic reactions, although they have their own specific adsorption capacities, equilibration times, and kinetic rates. Comprehensively analyzing the characterization data and adsorption performances of the particles shows that, the pore physical properties including the pore diameter distribution and volume obviously control the adsorption capacities, and well the pore surface chemical properties such as the functional groups affect the adsorption kinetics; the microstructure affects the performances through the synergistic effect of physical and chemical pathways and results in the special performances. Briefly, a particle has its special microstructure and then determinedly unique performance. The finding provides insights into the role of the microstructure of the particles in their performances, and significances for selecting and utilizing the adsorbents in water treatment.Highlights: Effect of the particle microstructure on TNT adsorption was reported. Chemical properties of the particle pores affected adsorption performance. Adsorption of TNT was a non-spontaneous entropy-enhancing endothermic reaction. The adsorption mechanism of clay minerals was revealed. [ABSTRACT FROM AUTHOR]

On days 2023‐364 and 2024‐034, the Juno spacecraft made close passages of Jupiter's moon Io, at altitudes of about 1,500 km. Data obtained from the first flyby, when the spacecraft was on magnetic field lines connected to both Jupiter and Io, revealed deep flux decreases. In addition, Juno's energetic particle detectors observed tens to hundreds of keV electron and proton beams. Such beams could be generated near Jupiter on field lines associated with Io. The second encounter occurred in the plasma wake and a more modest flux decrease was observed. Furthermore, data from both encounters suggest a spatially extensive decrease in >1 MeV electrons that includes regions inward of Io's orbit. In the immediate vicinity of Io, signatures of absorption likely dominate the data whereas diffusion and wave‐particle interactions are expected to be needed to understand MeV electron data in the wider spatial region around Io. Plain Language Summary: Jupiter's magnetospheric plasma overtakes Io in its orbit. This causes a cavity to be formed over the hemisphere of Io that leads its orbital motion. Within this cavity subtle details of the plasma and energetic charged particle environment can be extracted from the signal, usually dominated by radiation at these distances. Examples include beams traveling in the direction from Jupiter to the moon, with little evidence of reflection at Io. Another major finding of this work is that there is a large region both along Io's orbit and even radially inward of it with a lower level of MeV electron flux. Guided by previous modeling, the most likely candidates for shaping the data are absorption by the moon, wave‐particle interactions that can scatter particles into Jupiter's atmosphere, and diffusion. Key Points: Deep flux decreases over Io and in its immediate wake caused by losses to the moon's surface were observed in Juno JEDI dataJuno JEDI detected narrow field‐aligned beams of electrons and protons directed toward Io's north poleMoon absorption and wave‐particle interactions may explain the loss of >1 MeV electrons that extend both inward and outward of Io's orbit [ABSTRACT FROM AUTHOR]

Due to climate change, wildfires have increased in intensity and duration. While wildfires threaten lives directly, the smoke has more far-reaching adverse health impacts. During an extreme 2017 wildfire event, residents of Seeley Lake, Montana were exposed to unusually high levels of wood smoke (WS) causing sustained effects on lung function (decreased FEV1/FVC). Objective: The present study utilized an animal model of WS exposure to research cellular and molecular mechanisms of the resulting health effects. Methods: Mice were exposed to inhaled WS utilizing locally harvested wood to recapitulate community exposures. WS was generated at a rate resulting in a 5 mg/m3 PM2.5 exposure for five days. Results: This exposure resulted in a similar 0.28 mg/m2 particle deposition (lung surface area) in mice that was calculated for human exposure. As with the community observations, there was a significant effect on lung function, increased resistance, and decreased compliance, that was more pronounced in males at an extended (2 months) timepoint and males were more affected than females: ex vivo assays illustrated changes to alveolar macrophage functions (increased TNFα secretion and decreased efferocytosis). Female mice had significantly elevated IL-33 levels in lungs, however, pretreatment of male mice with IL-33 resulted in an abrogation of the observed WS effects, suggesting a dose-dependent role of IL-33. Additionally, there were greater immunotoxic effects in male mice. Discussion: These findings replicated the outcomes in humans and suggest that IL-33 is involved in a mechanism of the adverse effects of WS exposures that inform on potential sex differences. [ABSTRACT FROM AUTHOR]

A numerical simulation of the gasdynamic processes accompanying the formation and propagation of vortex rings obtained with the use of a piston-type generator has been performed. The formation of a vortex ring, the capture of particles of a disperse admixture by it, and their carry by the ring are considered. The numerical calculations were conducted with the use of nonstationary Navier–Stokes equations, and the movement of particles was defined using the discrete-trajectory method. The distribution of the admixture particles in a vortex ring was determined depending on the conditions of its formation. The influence of the characteristics of a vortex ring on the carry of a passive admixture by it was investigated. The reasons for the qualitative and quantitative differences between the losses of particles in a vortex ring in the path of its movement in different regimes are discussed. [ABSTRACT FROM AUTHOR]

In West African cities, the impacts of the air quality on the health of the population is expected to increase significantly in the near future. For the first time to our knowledge, we conducted a high-resolution modeling study over Abidjan (Côte d'Ivoire) using the WRF-Chem model and the simplified GOCART model to simulate carbonaceous aerosols BC and OC, sulfate, dust, sea salt, PM2.5, and PM10. The simulations were carried out during January and February 2019, a period over which there are databases of observations available. The DACCIWA inventory provided anthropogenic emissions at the regional scale, whereas a new emission inventory has been developed for the city of Abidjan. In 2019, the emissions were 4986.8 Gg for BC, 14,731.4 Gg for OC, and 7751.6 Gg for SO2. Domestic fires were the primary OC source (7719.5 Gg), while road traffic was the largest BC emitter (2198.8 Gg). Our modeling results generally overestimate urban particle concentrations, despite having a better agreement for those based on the inventory of the city of Abidjan. Modeled concentrations of BC are higher in administrative centers due to road traffic, while OC concentrations are significant in densely populated neighborhoods. [ABSTRACT FROM AUTHOR]

In the present study, magnesium nanoparticles (Mg NPs) were synthesized utilizing an aqueous extract of Berberis aristate rhizome and evaluated for antimicrobial and anti-inflammatory activity. Technofunctional properties of rhizome powder were evaluated and during thermal stability evaluation four stages of decomposition with a maximum delta Y value of 76.04 % was observed. Optimization of Mg NPs was carried out by employing eight different concentrations (C1-C8) and the C4 showed maximum absorbance at 330 nm confirming the NPs synthesis. The Mg NPs showed the particle size of 62 nm, zeta potential of −24.7 mV and hexagonal mprphology. Potential inhibition against S. aureus and E. coli (76.78 ± 0.05% and 74.62 ± 0.17%)and anti-inflammatory activity ranging from 42.43 ± 0.07–82.92 ± 0.04% was observed for Mg NPs. Therefore, green synthesis of Mg NPs is a promising approach for the development ofbiological active NPs to cure microbial infections. [ABSTRACT FROM AUTHOR]

Ultrasonic wave propagates with strong penetration, high stability, and has non-contact nature, therefore it is widely used in the petroleum industry. As an application example, an ultrasonic flowmeter can accurately measure the annular flow rate of water-based drilling fluid. According to the outlet flow rate, it can be noticed if there is an abnormal situation in the well to avoid accidents such as well kick and blowout. However, due to the attenuation of ultrasonic wave in the drilling fluid, the relevant research results are not reliable. Herein, based on the theory of acoustics, the influences of water-based drilling fluid density, solid particle size and solid particle number on the ultrasonic attenuation characteristics under different frequencies are studied by numerical simulation. First, the propagation characteristics of ultrasonic wave in water-based drilling fluid are systematically analyzed, then the accuracy of the above results is verified by laboratory tests. The results show that the ultrasonic attenuation rate is positively correlated with the solid particle size, solid particle number and ultrasonic frequency in water-based drilling fluid, while it is negatively correlated with the density of water-based drilling fluid. Furthermore, it is established that the ultrasonic energy decreases with increasing propagation distance. The results of this study can provide a theoretical basis and practical guidance for using an ultrasonic flowmeter to accurately measure the annulus return flow rate of drilling fluid and develop an intelligent drilling system, so as to improve the efficiency of field operation and drilling success rate. [ABSTRACT FROM AUTHOR]

In this research, we sought to establish whether adult non-native English speakers interpret aspectual phrasal verbs by means of the continuous or discontinuous position of the particle that goes with them and whether this is related to their level of proficiency in English as a second language (L2). An image selection task was designed and applied to adult native and non-native English speakers, the latter were divided into four groups based on their hours of exposure to the target language (100–200 h, 300–400 h, 600–700 h, +1000 h.). The results obtained suggest that the position of the particle can sometimes affect the interpretation of phrasal verbs of English by non-native speakers; however, this does not occur in the same way for all phrasal verbs, since the interpretation is also linked to the category to which they belong and to the particle present in each case. Finally, non-native speakers of English with a greater number of hours of exposure to the target language do not have a significantly different performance from non-native speakers when interpreting phrasal verbs, although in some cases the differences are pronounced. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to examine the forms and functions of answers to proposals for joint action, implemented through polar interrogatives, in Greek telephone calls. Our analysis indicates a distinct functional distribution of three types of accepting answers to such proposals. Particle-type answers do 'simple' acceptance of the proposal, i.e. they only display the respondent's willingness to take on the proposed action and nothing else, while repetition-type answers display the speaker's epistemic/deontic stance towards additional aspects of the proposal. With a third type of responses, speakers accept the proposal in a mitigated manner. Our findings align with Enfield et al.'s (2019) conclusion that particles serve as pragmatically unmarked polar answers. They do not, however, evince the prevalence of this type of answer to proposals to the same extent as to epistemically oriented polar interrogatives. [ABSTRACT FROM AUTHOR]

With the rapid development of biotechnology, the importance of microfluidic bioseparation and bioassay in biomedicine, clinical diagnosis, and other fields has become increasingly prominent. Microfluidic technology, with its significant advantages of high throughput, automated operation, and low sample consumption, has brought new breakthroughs in the field of biological separation and bioassay. In this paper, the latest research progress in microfluidic technology in the field of bioseparation and bioassay is reviewed. Then, we focus on the methods of bioseparation including active separation, passive separation, and hybrid separation. At the same time, the latest research results of our group in particle separation are introduced. Finally, some application examples or methods for bioassay after particle separation are listed, and the current challenges and future prospects of bioseparation and bioassay are discussed. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the influence of chitosan particles loaded with sodium sulfate on the structure and properties of the gelatin films by using gelatin as the film-forming matrix and adding chitosan particles loaded with sodium sulfate to prepare composite gelatin films. The thickness, hydration properties, barrier properties, mechanical properties, optical properties, thermal stability and oxidation resistance of the gelatin films were measured, and its structure was characterized. The results showed that the addition of chitosan particles loaded with sodium sulfate significantly decreased the thickness (P<0.05), significantly increased the swelling rate (P<0.05), decreased the dissolution rate from 79.41% to 18.21%, increased the tensile strength from 79.10 MPa to 128.96 MPa, increased the opacity from 3.75 to 6.77, improved the thermal stability, and increased the DPPH radical scavenging capacity from 14.41% to 65.05% of the gelatin films. However, there were no significant changes in the water vapor permeability and elongation at break of the gelatin films. In addition, there was a high compatibility between chitosan particles loaded with sodium sulfate and gelatin molecules, and the addition of chitosan particles loaded with sodium sulfate changed the structure of gelatin films. In conclusion, the incorporation of chitosan particles loaded with sodium sulfate can change the structure of gelatin films to some extent and improve the properties of gelatin films. This study provides theoretical guidance and data reference for the preparation and application of antioxidant composite gelatin films. [ABSTRACT FROM AUTHOR]

HypothesisThe dip coating of suspensions made of monodisperse non-Brownian spherical particles dispersed in a Newtonian fluid leads to different coating regimes depending on the ratio of the particle diameter to the thickness of the film entrained on the substrate. In particular, dilute particles dispersed in the liquid are entrained only above a threshold value of film thickness. In the case of anisotropic particles, in particular fibers, the smallest characteristic dimension will control the entrainment of the particle. Furthermore, it is possible to control the orientation of the anisotropic particles depending on the substrate geometry. In the thick film regime, the Landau-Levich-Derjaguin model remains valid if one account for the change in viscosity.ExperimentTo test the hypotheses, we performed dip-coating experiments with dilute suspensions of non-Brownian fibers with different length-to-diameter aspect ratios. We characterize the number of fibers entrained on the surface of the substrate as a function of the withdrawal velocity, allowing us to estimate a threshold capillary number below which all the particles remain in the liquid bath. Besides, we measure the angular distribution of the entrained fibers for two different substrate geometries: flat plates and cylindrical rods. We then measure the film thickness for more concentrated fiber suspensions.FindingsThe entrainment of the fibers on a flat plate and a cylindrical rod is primarily controlled by the smaller characteristic length of the fibers: their diameter. At first order, the entrainment threshold scales similarly to that of spherical particles. The length of the fibers only appears to have a minor influence on the entrainment threshold. No preferential alignment is observed for non-Brownian fibers on a flat plate, except for very thin films, whereas the fibers tend to align themselves along the axis of a cylindrical rod for a large enough ratio of the fiber length to the radius of the cylindrical rod. The Landau-Levich-Derjaguin law is recovered for more concentrated suspension by introducing an effective capillary number accounting for the change in viscosity.

The study aimed to investigate the influence of chitosan particles loaded with sodium sulfate on the structure and properties of the gelatin films by using gelatin as the film-forming matrix and adding chitosan particles loaded with sodium sulfate to prepare composite gelatin films. The thickness, hydration properties, barrier properties, mechanical properties, optical properties, thermal stability and oxidation resistance of the gelatin films were measured, and its structure was characterized. The results showed that the addition of chitosan particles loaded with sodium sulfate significantly decreased the thickness (P

[Display omitted] Aqueous solutions of long-chain water-soluble sucrose ester surfactants exhibit non-trivial response to temperature variations, revealing a peak in viscosity around 40–50 °C. While previous investigations have explored the structures within sucrose stearate systems at various constant temperatures, a comprehensive understanding of the entire temperature dependence and the underlying molecular factors, contributing to this phenomenon is currently missing. Temperature dependent properties and supramolecular structures formed in aqueous solutions of commercial sucrose palmitate were examined using SAXS/WAXS, DSC, optical microscopy, rheological measurements, NMR, and cryo-TEM. The underlying mechanism governing this unusual behavior is revealed and is shown to relate to the mono- to di-esters ratio in the solutions. Solutions primarily containing sucrose monoesters (monoesters molecules ≳ 98% of all surfactant molecules) exhibit behavior typical of nonionic surfactants, with minimal changes with temperature. In contrast, the coexistence of mono- and di-esters results in the formation of discrete monodisperse diester particles and a network of partially fused diester particles at low temperature. As the temperature approaches the diesters' melting point, wormlike mixed micelles form, causing a viscosity peak. The height of this peak increases significantly with the diester concentration. Further temperature increase leads to fluidization of surfactant tails and formation of branched micelles, while excess diester molecules phase separate into distinct droplets. [ABSTRACT FROM AUTHOR]

Quarry fines are secondary materials that can be reused for road construction, commonly after improving their properties through stabilising. To better understand and characterise these recycled materials, we created an image-based, two-dimensional representation of the particles that compose the material. This computational representation enables (1) the quantification of the (area-based) gradation from images, (2) a detailed particle-by-particle characterisation and (3) potentially, random rearrangement of the particles into reconstructed specimens for further computational analyses. The images of cement-stabilised quarry fines were obtained using a scanning electron microscope. The particles were isolated and characterised using image processes and a computational approach (MATLAB code). The techniques and code presented herein can be applied as well to other granular-based materials. The MATLAB code and associated files are available as an open resource in GitHub (). [ABSTRACT FROM AUTHOR]

This in vitro study investigated color stability of two photo-polymerized nano-filled and nano-hybrid composite resins in different polymerization modes immersed in different staining solutions before and after brushing. Disc-shaped specimens (n = 120) were prepared from two composite resins based on filler particle size: nano-filled (Filtek Z350, shade A1, 3M ESPE) and nano-hybrid (Spectra ST-HV, shade A1, Dentsply Sirona) composite resins (n = 60 per composite type). Specimens of each resin type were photopolymerized using the following polymerization modes: LED conventional, ramp, and pulse (n = 20 specimens per resin type and LED mode). After preparation, baseline color of the specimens was evaluated using a spectrophotometer (Easyshade V, VITA), and color change was evaluated using the CIE L*a*b* formula. Specimens were soaked in distilled water for 4 weeks in separate containers. The specimens from each polymerization-mode group were separated into two groups of 10 specimens; one group was stored in tea and the other group was stored in cola, each 1 hour daily for 4 weeks. After 4 weeks, the color was measured again. The specimens were brushed for 2 minutes under 200-g weight using an electronically powered toothbrush on the polymerized side of the specimen. The color was reevaluated immediately after brushing. Color-difference data (ΔE) between groups were analyzed by one-way analysis of variance for main comparison and by independent t test for color change after brushing. Nano-filled composite resin was more color-stable than nano-hybrid composite resin (P < .001), regardless of the staining media. For both composite resin types, the conventional polymerization method produced a more color-stable result (P < .0001). ΔE after brushing was reduced significantly (P < .0001). Both staining solutions have significant effects on color change, with tea staining more than cola (P < .0001). Nanofilled composite resin had greater color stability than nano-hybrid composite resin after immersion in staining solutions. Polymerization mode influences the color stability of both composite resin types. [ABSTRACT FROM AUTHOR]

Abstract Higher concentrations of air pollutants, such as nitrogen dioxide (NO $$_\text {2}$$ 2 ) and particulate matter (PM), are observed in streets compared to the urban background. These concentrations could be predominantly attributed to road traffic, which remains an important source despite relentless efforts. In this study, performed over the Paris area, the impacts of the evolution of the fleet composition on urban air quality down to the street scale is assessed with two scenarios assuming the introduction of very-low-emission vehicles. Exhaust emission factors for these vehicles are based on the improvement of engine and after-treatment technologies, leading to factors lower than those proposed for the European emission standard Euro 7. Using the year 2014 as the baseline, very-low-emission vehicles are introduced up to the year 2030 for the Paris region. NO $$_\text {2}$$ 2 emissions are thus reduced by 68 % in streets, and concentrations by 53 %. However, PM concentration reduction is limited to 18 % in streets as non-exhaust emissions from tyre and brake wear and road abrasion are preponderant. PM emissions from non-exhaust sources represent 59 % of the total road-traffic emission of PM in 2014 and 89 % in 2030. Non-regulated pollutant concentrations are also reduced, by 42 % for black carbon and 30 % for organic matter. Considering only very-low-emission and electric vehicles in the fleet further reduce NO $$_\text {2}$$ 2 emissions and concentrations by 99.5 % and 80 % respectively. PM concentrations are only reduced by 22 %. This study highlights the high reduction potential of NO $$_\text {2}$$ 2 concentrations with very-low-emission and electric vehicles, because of reduction of exhaust emissions. However, difficulties remain to reduce PM concentrations in urban areas, with the large majority of PM traffic emissions coming from non-exhaust sources.

The further development of lightweight and energy-saving engineering materials is a great challenge for scientists in the 21st century. Magnesium and its composites, as the metal materials with the lowest density among metal structural materials, have good thermal conductivity, good dimensional stability, high specific strength, good biocompatibility, which can meet the requirements of energy-saving, emission reduction, environmental protection. In recent years, magnesium and its composites have found the major applications in various fields such as aerospace, automotive industry, electronics and medical industry. However, the fabrication of magnesium matrix composites is difficult, and the deformation behaviors and strengthening mechanisms of particulate reinforced magnesium matrix composites have unique characteristics. This article reviews the recent research progress of the magnesium matrix composites, including different fabrication methods and strengthening mechanisms. According to the classification of solidification rate, the advantages and disadvantages of various techniques used to fabricate magnesium matrix composites were introduced. The traditional and novel fabrication techniques were discussed. The influence mechanisms of particulates on solidification microstructures, recrystallization behaviors, texture strength and twin behaviors of magnesium matrix composites during solidification and extrusion were summarized, and the roles of particulates in solidification and extrusion of magnesium matrix composites were analyzed. The strengthening mechanisms of particulates on the mechanical properties, corrosion resistance, fatigue resistance and creep resistance of magnesium matrix composites were revealed. Finally, the development prospect and research direction of magnesium matrix composites were prospected. It is hoped that this paper can provide a reference for the further development of magnesium matrix composites.

Background: Tendon stem/progenitor cell (TSPC) senescence contributes to tendon degeneration and impaired tendon repair, resulting in age-related tendon disorders. Ferroptosis, a unique iron-dependent form of programmed cell death, might participate in the process of senescence. However, whether ferroptosis plays a role in TSPC senescence and tendon regeneration remains unclear. Recent studies reported that Platelet-derived exosomes (PL-Exos) might provide significant advantages in musculoskeletal regeneration and inflammation regulation. The effects and mechanism of PL-Exos on TSPC senescence and tendon regeneration are worthy of further study. Methods: Herein, we examined the role of ferroptosis in the pathogenesis of TSPC senescence. PL-Exos were isolated and determined by TEM, particle size analysis, western blot and mass spectrometry identification. We investigated the function and underlying mechanisms of PL-Exos in TSPC senescence and ferroptosis via western blot, real-time quantitative polymerase chain reaction, and immunofluorescence analysis in vitro. Tendon regeneration was evaluated by HE staining, Safranin-O staining, and biomechanical tests in a rotator cuff tear model in rats. Results: We discovered that ferroptosis was involved in senescent TSPCs. Furthermore, PL-Exos mitigated the aging phenotypes and ferroptosis of TSPCs induced by t-BHP and preserved their proliferation and tenogenic capacity. The in vivo animal results indicated that PL-Exos improved tendon-bone healing properties and mechanical strength. Mechanistically, PL-Exos activated AMPK phosphorylation and the downstream nuclear factor erythroid 2-related factor 2 (Nrf2)/glutathione peroxidase 4 (GPX4) signaling pathway, leading to the suppression of lipid peroxidation. AMPK inhibition or GPX4 inhibition blocked the protective effect of PL-Exos against t-BHP-induced ferroptosis and senescence. Conclusion: In conclusion, ferroptosis might play a crucial role in TSPC aging. AMPK/Nrf2/GPX4 activation by PL-Exos was found to inhibit ferroptosis, consequently leading to the suppression of senescence in TSPCs. Our results provided new theoretical evidence for the potential application of PL-Exos to restrain tendon degeneration and promote tendon regeneration. [ABSTRACT FROM AUTHOR]

The complex air environment makes it urgent to build good and safe indoor environments, and the study and application of new materials have become the focus of current research. In this study, we tested and analyzed the structural parameters and filtration performances of the four most commonly used new filter materials in the current market. The results showed that all four new filter materials showed a trend of first increasing and then decreasing their filtration efficiency with an increase in filtration velocity. The filtration efficiency of the materials was as follows: PTFE > glass fiber > nanomaterial > electret. The filtration efficiency of all materials reached its maximum when the filtration velocity was 0.2 m/s. The filtration efficiency of the PTFE for PM10, PM2.5, and PM1.0 was higher than that of the other three materials, with values of 0.87% to 24.93%, 1.21% to 18.69%, and 0.56% to 16.03%, respectively. PTFE was more effective in capturing particles smaller than 1.0 μm. Within the testing velocity range, the resistance of the filter materials was as follows: glass fiber > PTFE > electret > nanomaterial, and the resistance of the four materials showed a good fitting effect. It is also necessary to match the resistance with the filtration efficiency during use, as well as to study the effectiveness of filter materials in blocking microorganisms and absorbing toxic gases. Overall, PTFE showed the best comprehensive performance, as well as providing data support for the selection of related materials or the synthesis and research of filter materials in the future. [ABSTRACT FROM AUTHOR]

The study concerns measurement and evaluation of the geometric characteristics of the inhalable fraction of particulate matter generated in the process of grinding dental restorations, which is a process that generates a large quantity of particulates. The research is based on measurements taken with a personal sampler, whereby the characteristics of particulates are determined based on the particle mass collected on filters. The collected filters were examined using scanning electron microscopy (SEM), and the resulting micrographs were processed through image analysis. The complex geometry of particles was examined through the analysis of 14 parameters, of which 6 define size and 8 describe morphological characteristics. Two software programs were used for the image analysis process to gather a wide range of parameters describing particle geometry. The relationship and dependence between the geometric parameters used to describe particle shape and size were investigated using multivariate analysis methods. Through correlation analysis, principal component analysis, and cluster analysis, parameter selection and reduction were performed to provide an understanding of the particles inhaled by exposed workers, which also influences the biological response of exposed organisms and the burden on the working environment. [ABSTRACT FROM AUTHOR]

Plastic is one of the most widely used materials worldwide. The problem with plastic arises when it becomes waste, which needs to be treated. One option is to transform plastic waste into synthetic fuels, which can be used as replacements or additives for conventional fossil fuels and can contribute to more sustainable plastic waste treatment compared with landfilling and other traditional waste management processes. Thermal and catalytic pyrolysis are common processes in which synthetic fuels can be produced from plastic waste. The properties of pyrolytic oil are similar to those of fossil fuels, but different additives and plastic stabilizers can affect the quality of these synthetic fuels. The quality of fuels and the permissible particle sizes and number density are regulated by fuel standards. Particle size in fuels is also regulated by fuel filters in vehicles, which are usually designed to capture particles larger than 4 μm. Problems can arise with the number density (quantity) of particles in synthetic fuels compared to that in fossil fuels. The present work is a numerical study of how particle size and number density (quantity) influence cavitation phenomena and cavitation erosion (abrasion) in common-rail diesel injectors. The results provide more information on whether pyrolysis oil (synthetic fuel) from plastic waste can be used as a substitute for fossil fuels and whether their use can contribute to more sustainable plastic waste treatments. The results indicate that the particle size and number density slightly influence cavitation phenomena in diesel injectors and significantly influence abrasion. [ABSTRACT FROM AUTHOR]

Higher concentrations of air pollutants, such as nitrogen dioxide (NO 2 ) and particulate matter (PM), are observed in streets compared to the urban background. These concentrations could be predominantly attributed to road traffic, which remains an important source despite relentless efforts. In this study, performed over the Paris area, the impacts of the evolution of the fleet composition on urban air quality down to the street scale is assessed with two scenarios assuming the introduction of very-low-emission vehicles. Exhaust emission factors for these vehicles are based on the improvement of engine and after-treatment technologies, leading to factors lower than those proposed for the European emission standard Euro 7. Using the year 2014 as the baseline, very-low-emission vehicles are introduced up to the year 2030 for the Paris region. NO 2 emissions are thus reduced by 68 % in streets, and concentrations by 53 %. However, PM concentration reduction is limited to 18 % in streets as non-exhaust emissions from tyre and brake wear and road abrasion are preponderant. PM emissions from non-exhaust sources represent 59 % of the total road-traffic emission of PM in 2014 and 89 % in 2030. Non-regulated pollutant concentrations are also reduced, by 42 % for black carbon and 30 % for organic matter. Considering only very-low-emission and electric vehicles in the fleet further reduce NO 2 emissions and concentrations by 99.5 % and 80 % respectively. PM concentrations are only reduced by 22 %. This study highlights the high reduction potential of NO 2 concentrations with very-low-emission and electric vehicles, because of reduction of exhaust emissions. However, difficulties remain to reduce PM concentrations in urban areas, with the large majority of PM traffic emissions coming from non-exhaust sources. [ABSTRACT FROM AUTHOR]

Plastic materials are used in various domains, such as constructions, textile, or medical applications, due to their durability and versatility. Despite plastics contribution to human wellbeing, these materials can also have a negative impact on ecosystems, leading to water pollution and loss of aquatic life. However, no study has been made, so far, to determine the impact of plastic products on natural particle size distribution in water systems. The aim of this study is to evaluate if plastic affects aquatic particulate matter of different size ranges, from 0.3 to 16 000 nm. Three types of plastics (polystyrene [PS], polypropylene [PP], and low‐density polyethylene [LDPE]) have been added to lake water samples and incubated for nine months at room temperature. Results show that the average particle size increases toward the end of the experiment indicating that small particles (<1200 nm) adhere to plastic surfaces, while medium and large particles sediment in the water sample. Also, substances migrating from plastic may alter the aggregating properties of particles. However, the influence may be less substantial in the environment, as plastic types and concentrations differ. Moreover, more studies are needed to establish additional implications in relation to bacterial communities, transport of pollutants, or chemical composition. [ABSTRACT FROM AUTHOR]

The effect of removing suction on energy consumption, displacement, and separation of particles with different sizes and densities in the jig was investigated by CFD-DEM coupling. Water velocity functions were categorized into four modes: normal sinusoidal, partial removal of suction, complete removal of suction, and optimal. Particles rise to a certain height in the normal sinusoidal mode, while their jump height increases in the case of partial or complete removal of suction. The jump was controlled by fluid and added (Hutch) water velocities. Increasing the maximum jump height of particles leads to a decrease in separation, an increase in operational costs, and heightened particle mixing and energy consumption. In both modes of partial or complete suction removal, the fluid velocity should be reduced. The extent of velocity reduction depends on the power required to move the particles. The simulation of coarse particles (7 and 8 mm) revealed that in the complete removal of suction, the velocity should be decreased to less than half of the normal sinusoidal mode, and the hutch water velocity should be equivalent to the velocity amplitude. The energy consumption for the optimal mode was significantly lower than that of the other modes. [ABSTRACT FROM AUTHOR]

This article explores the challenges and potential impacts of micro and nanoplastic particles (MNPs) on the innate immune system. MNPs, small plastic particles, are released into the environment and can interact with various species, including humans. The innate immune system, responsible for recognizing and eliminating foreign materials, plays a crucial role in responding to MNPs. The article suggests that studying the effects of MNPs on the innate immune system across different species can provide valuable insights into the mechanisms and potential impacts of MNP exposure. It emphasizes the importance of adopting an evolutionary immunology framework and proposes using in vitro and in vivo models, as well as genome-wide association studies and multiomics analyses, to understand these interactions. This research aligns with the One Health initiative and can contribute to a better understanding of the environmental and human health risks associated with MNP pollution. [Extracted from the article]

Background: Periodontal diseases may benefit more from topical treatments with nanoparticles rather than systemic treatments due to advantages such as higher stability and controlled release profile. This study investigated the preparation and characterization of thermosensitive gel formulations containing clindamycin-loaded niosomes and solid lipid nanoparticles (SLNs) loaded with fluconazole (FLZ), as well as their in vitro antibacterial and antifungal effects in the treatment of common microorganisms that cause periodontal diseases. Methods: This study loaded niosomes and SLNs with clindamycin and FLZ, respectively, and assessed their loading efficiency, particle size, and zeta potential. The particles were characterized using a variety of methods such as differential scanning calorimetry (DSC), dynamic light scattering (DLS), and Transmission Electron Microscopy (TEM). Thermosensitive gels were formulated by combining these particles and their viscosity, gelation temperature, in-vitro release profile, as well as antibacterial and antifungal effects were evaluated. Results: Both types of these nanoparticles were found to be spherical (TEM) with a mean particle size of 243.03 nm in niosomes and 171.97 nm in SLNs (DLS), and respective zeta potentials of -23.3 and -15. The loading rate was 98% in niosomes and 51% in SLNs. The release profiles of niosomal formulations were slower than those of the SLNs. Both formulations allowed the release of the drug by first-order kinetic. Additionally, the gel formulation presented a slower release of both drugs compared to niosomes and SLNs suspensions. Conclusion: Thermosensitive gels containing clindamycin-loaded niosomes and/or FLZ-SLNs were found to effectively fight the periodontitis-causing bacteria and fungi. [ABSTRACT FROM AUTHOR]

In multiphase particulate systems, the turbulence of the continuous phase (gas or liquid) is modulated due to interactions between the continuous phase and the suspended particles. Such phenomena are non-trivial in the essence that addition of a dispersed phase to a turbulent flow complicates the existing flow patterns depending on the physical properties of the particles leading to either augmentation or attenuation of continuous phase turbulence. In the present study, this aspect has been comprehensively analysed based on the available experimental data obtained from the well-studied turbulent flow systems such as channel and pipes, free jets and grids. Relevant non-dimensional parameters such as particle diameter to integral length scale ratio, Stokes number, particle volume fraction, particle momentum number, and particle Reynolds number have been utilised to characterise the reported turbulence modulation behavior. Some limitations of these commonly used dimensionless parameters to characterise turbulence modulation are discussed, and possible improvements are suggested. [ABSTRACT FROM AUTHOR]

This study investigates the impact of various instrumentation techniques on material removal and surface changes in titanium (Ti)- and zirconia (Zr) implant discs. Ti- and Zr discs were subjected to standardized experiments using various instruments including airflow, ultrasound, carbide, and diamond burs. Instrumentation was performed for 60 s with continuous automatic motion. Abrasion and changes in surface roughness were assessed using profilometry, while scanning electron microscopy was used to examine morphological changes and particle size. Carbide burs predominantly caused abrasion on Ti discs, while diamond burs caused more abrasion on Zr discs. The Ti discs were more susceptible to surface changes. However, among the materials tested, machined Zr discs treated with diamond burs produced the largest particle. In certain cases, a statistical significance (p < 0.05) was observed between the groups, while in others, there was no considerable difference among the means (p > 0.05). These results highlighted the statistical significance of our findings. These results found diverse alterations in surface characteristics of Ti- and Zr discs due to different instruments, with carbide and diamond burs causing notable effects. The findings highlight the need for a careful balance between promoting healing and minimizing harm during implantoplasty. [ABSTRACT FROM AUTHOR]

Inline (or in situ) photon density wave spectroscopy was used to monitor the disintegration of secondary titania particles into their primary particles. Photon density wave spectroscopy can be applied to determine the reduced scattering coefficient μs′$\mu _{\mathrm{s}}^{\prime}$ of a dispersion without dilution or calibration, and thus enables process analysis in materials that are usually unsuitable for established particle characterization techniques. In this work, amorphous titania particles were precipitated from tetraethyl orthotitanate in ethanol by addition of water in presence of different alkali metal salts (NaCl, KCl, CsCl, K2SO4) with concentrations between 0 and 1.6 mM. The present results suggest that the synthesized titania secondary particles disintegrate into their primary particles if the electrostatic repulsion between the primary particles is promoted. This can be achieved by an increased alkali chloride concentration in the synthesis or by addition of larger alkali metal ions. In contrast, the particles are only weakly charged upon addition of sulfate ions, and the disintegration stops. The conclusions drawn from photon density wave spectroscopy results are supported by gravimetric determination of the particle yield, dynamic light scattering measurements, zeta‐potential measurements, and electron micrographs. Additionally, the disintegration was driven to completion by addition of hydrochloric acid to create a transparent suspension of titania primary particles as small as 4.7 nm. [ABSTRACT FROM AUTHOR]

Sufficient homogeneity of the certified parameter(s) over the whole fill series of a matrix reference material (RM) is a fundamental quality criterion. In practice, the heterogeneity of the target parameter is evaluated, whereby a relative value can be calculated of how much the target parameter is varying over the RM-batch. A high degree of homogeneity (low heterogeneity) is an inherent quality mark of a good RM. Here, we report how challenging matrix RMs were produced by using particle suspensions at the core of the material processing step. The examples of matrix RMs produced span from whole water reference materials for persistent organic pollutants, PM2.5-like atmospheric dust certified for specific ions to microplastic RMs. Most of these RMs were subsequently used in different phases of analytical method development or for method validation. Common to all these matrices is that they cannot be easily mixed, handled, or dosed to prepare larger sample batches. In all cases, a continuously stirred suspension of particles was used during material processing. In general, relative between-bottle heterogeneities from 1.6 to 6% were achieved for the target parameters in these matrix presentations. Concerning developments of new CRMs in emerging fields, the co-dependence between the availability of validated analytical methods with good repeatability and testing materials with a known and high homogeneity of the target parameter(s) becomes particularly challenging. This situation is an RM/Method causality dilemma. To overcome that hurdle, strategies are proposed for stepwise processes where RM producers and a network of analytical method developers could work hand in hand. In addition, development of a portfolio of inexpensive and well-homogenised common samples coupled with a reporting interface is suggested. This would benefit method developers and RM producers alike. As more and more data is compiled for a specific matrix, it paves the way for new and challenging RMs that can later be used by a wider community. [ABSTRACT FROM AUTHOR]