Particle Size Research Articles

The Cumulation of Debris Clouds around a Fast-rotating Asteroid

Abstract The rotational mass loss has been realized to be a prevalent mechanism to produce low-speed debris near the asteroid, and the size composition of the asteroid’s surface regolith has been closely measured by in situ explorations. However, the full-scale evolution of the shedding debris has not been examined using the observed particle sizes, which may hold vital clues to the initial growth of an asteroid moonlet and help us to understand the general mechanisms that dominate the formation of asteroid systems. This paper presents our study on the cumulative evolution of the debris cloud formed by a rotationally unstable asteroid. A semianalytical model is developed to characterize the spatiotemporal evolution of the debris cloud posterior to a shedding event. Large-scale discrete element method (DEM) simulations are performed to quantify the clustering behavior of the debris particles in the mechanical environment near the asteroid. As a result, we found that the cumulation of a steady debris cloud is dominated by large pieces of debris, and the shedding particles follow a common migration trend, which fundamentally determines the mass distribution of the debris cloud. For the accretion analysis, we sketched the life cycle of a debris cluster and showed its dependency on particle size. The DEM simulations adopt physical parameters estimated from observations and asteroid missions. The results confirm that porous fluffy cluster structures can form shortly after a shedding event with magnitudes the same as the observed shedding activities. Measurements of these structures show that they themselves possess a certain strength and have the capacity to collisions to absorb dissociative particles that collide with them.

Estimating the snow density using collocated Parsivel and Micro-Rain Radar measurements: a preliminary study from ICE-POP 2017/2018

Abstract. A new method is developed to derive the bulk density and bulk water fraction of a population of particles from collocated measurements from the Micro-Rain Radar (MRR) and Particle Size and Velocity disdrometer (Parsivel). A rigorous particle-scattering simulation, namely the T-matrix method, is applied to Parsivel's particle size distribution data to calculate the reflectivity (ZHH). The possible combinations of the particle's ice, air, and water are derived to compare them with the MRR-measured ZHH. The combination of the minimum water fraction and maximum ice fraction subsequently determines the bulk density (ρbulk). The proposed method is applied to the data collected from the International Collaborative Experiments for Pyeongchang 2018 Olympic and Paralympic winter games (ICE-POP 2018) projects and its pre-campaign. The estimated ρbulk was examined independently by a comparison of the liquid-equivalent snowfall rate (SR) of collocated Pluvio devices. The bias values are adequately low (SR: −0.25–0.06 mm h−1). The retrieved bulk density also shows good consistency with collocated Precipitation Imaging Package (PIP) retrievals. The results indicate the capability of the proposed algorithm to derive reliable ρbulk, leveraging the compact and easily deployable designs of MRR and Parsivel. The derived bulk density of the two warm–low cases (28 February and 7 March 2018) shares a similar transition as the systems were decaying. The higher bulk density and bulk water fraction were found in the coastal sites (BKC and GWU have a median value of ρbulk and are 0.05 to 0.12 g cm−3), typically accompanied by higher liquid-water constituents (mean values of the top 5 % bulk water fraction are 0.07 to 0.45) than the inland sites (YPO and MHS have a median value of ρbulk and are 0.06 to 0.10, and mean values of the top 5 % bulk water fraction are 0.001 to 0.008) during such synoptic conditions.

Crystallite size and phase purity in Pb1-xSrxTiO3 ferroelectric perovskites for biomedical applications via controlled sintering

ABSTRACT Lead strontium titanate (Pb1-xSrx)TiO3 (PST) is a ferroelectric perovskite material with tunable properties, including Curie temperature, spontaneous polarization, and high dielectric permittivity, making it promising for advanced biomedical applications, such as biosensors, bioimaging, and light-activated therapeutics. This study investigates the effect of varying sintering temperatures on the crystallite size and phase purity of PST, aiming to optimize its performance for biomedical devices. PbCO3, SrCO3, and TiO2 powders were processed via ball milling for 58 hours, followed by sintering at temperatures ranging from 500°C to 1100°C. Laser diffraction particle size analysis and X-ray diffraction (XRD) were used to assess the particle size and crystal phase transformations. The results demonstrate that higher sintering temperatures improve the PST phase composition, reducing impurities and enhancing crystallite growth. The most significant crystal growth was observed at 900°C, while the optimal phase purity and crystallite size (91.5 nm) were achieved at 1100°C, producing 100% single-phase PST. These findings emphasize the critical role of sintering temperature in tailoring PST’s properties, enhancing its suitability for electronic and microelectronic biomedical devices. Controlled sintering in perovskite materials opens new pathways for their application in medical diagnostics and therapeutic technologies.

Nonalkaline Fabrication of Al-Based Metal-Organic Frameworks with Tailored Water Sorption Properties via Polymeric Hydroxy-Aluminum Basicity Modulation.

Metal-organic frameworks (MOFs) are porous crystalline materials composed of metallic nodes and organic ligands, demonstrating increasing potential in water harvesting in arid and semiarid regions. This study presents a nonalkaline, water-based, and scalable synthesis strategy designed to adjust the water sorption properties of aluminum-based MOFs (Al-MOFs), specifically, AlFum and MOF-303, by modifying the basicity of the metal source, polymeric hydroxy-aluminum, as an alternative. Characterizations, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analyses (TGA), confirmed the successful synthesis of Al-MOFs. The results revealed that high-basicity polymeric hydroxy-aluminum introduced additional mesoscopic intraparticle defects, interparticle voids, and hydrophilic surface sites to the primary microporous Al-MOFs. This led to an enhanced external surface area and uniformity in the particle size. Consequently, the water sorption performance of basicity-modulated Al-MOFs was significantly improved. Specifically, within the typical working humidity between 0.05 and 0.3, using polymeric hydroxy-aluminum of the highest basicity resulted in a 23% and 68% increase in water uptake for AlFum and MOF-303, respectively, achieving capacities of 0.43 and 0.37 g·g-1. Cyclic water adsorption-desorption tests further indicated the hydrolytic stability of prepared Al-MOFs. This study offers a novel approach to engineering MOF properties through metal source modulation, with important implications for applications in water harvesting and heat transfer.

Alginate-chitosan hydrogel formulations for VEGFA expressed baculovirus delivery promoting angiogenesis for wound healing and revascularization

Abstract Background Baculoviruses, engineered to express growth factors, offer a promising avenue for short-term gene therapy, such as wound dressings, due to their safety and specificity. Encapsulation in natural polymers like alginate and chitosan addresses limitations like serum inactivation and fragility, while promoting sustained delivery and shielding from immune inactivation. Wound healing involves complex processes that can be enhanced by maintaining an antimicrobial, moist environment, which promotes cell migration and angiogenesis. Vascular endothelial cell growth factor A (VEGFA) is known to be one of the most potent pro-angiogenic factors and plays a key role in wound healing. Purpose This investigation seeks to enhance wound healing and angiogenesis, support the revascularization process, and provide anti-inflammatory and anti-microbial effects. Additionally, it aims to assess the preclinical efficacy and safety of the approach. Methods Ionic cross-linking was used for virus encapsulation under aseptic conditions. The capsules were assessed for their surface morphology, particle size, zeta potential, and in vitro release profile. Additionally, their therapeutic potential was studied using cell lines. The efficacy of hydrogel delivery of VEGFA-expressing baculoviruses in promoting cell migration and angiogenesis for wound healing applications was investigated on Human Umbilical Vein Endothelial Cells (HUVECs). Hydrogel morphology, swelling, and encapsulation efficiency were evaluated, along with endothelial tube formation assays and hemocompatibility studies on HUVECs. Results Encapsulation of baculovirus expressing the VEGFA gene in alginate and chitosan–alginate hydrogels achieve a high encapsulation efficiency of 99.9%. This allows for prolonged virus delivery and an increased therapeutic window. The encapsulated baculovirus maintains activity and is released over eight days, with a transduction efficiency of over 40%. This promotes tube formation, cell proliferation, and cell migration for angiogenesis, particularly beneficial for chronic wound-healing applications. The hydrogels also prevented E. coli and C. albicans growth directly below and inhibited C. albicans growth surrounding the alginate–chitosan hydrogels. The hydrogels demonstrated no cytotoxicity and good blood compatibility. Conclusion This proof of concept underscores the potential of encapsulated baculovirus delivery systems for various gene therapy applications including cardiovascular tissue regeneration and revascularization.

A baculoviral gene and drug-eluting (GDES) stent to promote re-endothelialization and prevent restenosis caused by atherosclerosis

Abstract Background Coronary artery disease (CAD) is a prevalent condition affecting approximately one in every 20 individuals over the age of 20, resulting in significant health and economic burdens worldwide. Atherosclerosis, characterized by plaque buildup in the arteries, is a leading cause of CAD, involving endothelial dysfunction, inflammation, and smooth muscle cell hyperproliferation. The standard interventions for CAD, namely bare-metal stents (BMS) or drug-eluting stents (DES), often lead to complications such as blood clotting, inflammation, and arterial re-narrowing, necessitating further interventions and potentially leading to severe outcomes like heart failure, stroke, or death. Additionally, the TGFβ1 gene regulates SMC proliferation and ECM secretion, promoting endothelial cell proliferation, inhibiting smooth muscle cell hyperproliferation, reducing reactive oxygen species production. Purpose This innovative stent aims to mitigate complications associated with conventional stents by promoting endothelial health and preventing inflammation and hyperproliferation downstream. The purpose of this study is to design a new gene and drug eluting stent and evaluate their preclinical efficacy and safety in addressing some of the key limitations of currently available coronary stents. Methods The TGFβ1 expressing baculoviruses loaded PLGA nanoparticles are prepared by double emulsion solvent evaporation method. The formulated nanoparticles were characterized by their surface morphology, particle size, zeta potential, and in vitro release. Moreover, the designed nanoparticles undergo a further investigation for their therapeutic efficiency using cell lines. The GDES is synthesized by dip-coating a BMS into a solution containing Everolimus and genipin carrying baculoviruses expressing TGFβ1 in nanoparticles. The stent elutes the gene and drug over specific durations pertaining to a sustained release profile. The study assesses the functionality and safety of the GDES through in vitro and in vivo experiments, including cell culture studies and animal models. Results The PLGA nanoparticles at 115.3±1.4 nm with a polydipersity (pdi) index of 0.152 have a sustained release profile for the TGFβ1 expressing baculovirus. The findings demonstrate that the GDES effectively promotes endothelial health and prevents inflammation and hyperproliferation downstream. The expression of TGFβ1 facilitates the formation of a fully reconstituted endothelial lining, reducing the risk of complications. Additionally, the prolonged release of Everolimus prevents inflammation and the progression of neointimal hyperplasia. The stent coating and system exhibit non-cytotoxicity and hemocompatibility, ensuring safety during expansion and degradation over time. Overall, the combined action of gene and drug elution in the GDES shows promising results in addressing current complications associated with cardiovascular stents.

Diacerein-loaded surface modified iron oxide microparticles (SMIOMPs): an emerging magnetic system for management of osteoarthritis via intra-articular injection

IntroductionOsteoarthritis (OA) is regarded as one of the most prevealent irreversible joint degenerative disorder worldwide. Recently, considerable interest in utilizing intra-articular (IA) injections for managing OA has been raised.MethodsIn this study, IA injectable surface modified iron oxide microparticles (SMIOMPs) loaded with Diacerein (DCN) were developed. The effects of formulation parameters on particle size, entrapment efficiency, and zeta potential were explored using factorial design. The optimized formulation was characterized regarding morphology and in vitro release. Differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR) were done to assess interactions. Further, sterilization and in vivo performance in rats with induced arthritis has been performed for the optimized formulation.Results and DiscussionThe selected optimized system included 2M FeCL3 and 1% chitosan as a surface modifier achieved high drug entrapment of 85.25% with a PS of 1.54 µm and sustained DCN release. Morphological examination of the optimized formulation revealed spherical particles with chitosan coat. DSC and FTIR results indicated the absence of undesired interactions between DCN and the used components. No significant change in the measured parameters was observed following sterilization using gamma radiation. In vivo assessment revealed superior performance for the optimized formulation in reducing cartilage inflammation and degradation. Plasma levels of tumor necrosis factor α and Interleukin-1 beta, as well as knee diameter, were significantly reduced in the treated groups compared to the untreated ones.ConclusionOverall, the results suggest that the proposed DCN-loaded SMIOMPs represent a promising advancement in the arena of cartilage regeneration.

Utilising date palm fibres as a permeable reactive barrier to remove methylene blue dye from groundwater: a batch and continuous adsorption study.

This study aimed to utilise cheap and abundantly available date palm fibre (DPF) wastes for the remediation of methylene blue (MLB) dye-contaminated groundwater. The DPF adsorbents were first prepared, followed by various characterisation analyses, including surface morphology, functional groups, and material structure. Subsequently, the DPF adsorbents were applied in the batch and continuous adsorption studies to assess the MLB dye removal from aqueous environments. The batch adsorption study achieved 98% maximum removal efficiency with a contact time, adsorbents dosage, initial pH, temperature, particle size, initial dye concentration, and agitation speed of 105min, 3g/L, 7.0, 45°C, 0.075mm, 50mg/L, and 150rpm, respectively. Langmuir was the best-fitted isotherm model depending on a higher correlation coefficient (R2 = 0.985), with a maximum monolayer dye adsorption capacity (qmax) of 54.204mg/g. Additionally, the second order was the best-fitted kinetic model (R2 = 0.990), indicating that MLB dye was removed through chemisorption. Besides, the positive enthalpy change (ΔH°) and negative Gibb's free energy (ΔG°) values verified the endothermic process and spontaneous adsorption. According to the impact analysis of initial dye concentrations and flow rates on the permeable reactive barrier (PRB) performance in the continuous adsorption study using the Thomas, Belter, and Yan models, the experimental results and predicted breakthrough curves reflected an excellent agreement (R2 ≥ 0.8767) and a sum of squared errors (SSE) ≤ 0.4834. In short, the results demonstrated DPF as an effective adsorbent material in PRB technology.

Production of (B4C+FeTi) reinforced and Fe based composites by mechanical alloying

Abstract In this study, the microstructure and mechanical performance of Fe-based composites reinforced by FeTi+B4C at various ratios were determined. The study was based on the production of Fe based nano carbide and boride (B4C, Fe2B, Fe7C3, TiB2) reinforced composites. Mechanical alloying technique was chosen to reduce the reinforcement material to nano size and distribute it homogeneously. Sintering temperature was used as 1,100 °C and sintering time as 2 h. The reionforcement “FeTi+B4C” ratio was raised up to 15 wt.%. The microstructure and phases of the composite samples were descrived by scanning electron microscopy, energy dispersive spectroscopy, X-RD analysis and hardness. The concentration of voids and the stiffness changes of the samples were determined. The size of TiC and TiB2 particles reduced significantly with the rise in B4C ratio. Since the hardness of TiB2 was less than that of the B4C matrix, the hardness reduced with increasing TiB2 ratio.

Triple-hormone receptor agonist retatrutide significantly improves lipoprotein and apolipoprotein profiles in participants with obesity or overweight

Abstract Background In a phase 2 study in participants who have obesity or overweight but not type 2 diabetes (T2D) (n=338), retatrutide (RETA), an agonist of GIP, GLP-1 and glucagon receptors, reduced body weight, glycated hemoglobin, triglycerides (TG), LDL-C and VLDL-C. Purpose To better understand the effects of RETA on the serum lipid profile we analyzed changes in apolipoprotein levels and distribution and size of lipoprotein particles. Methods Adult participants with obesity (BMI ≥30 kg/m2), or overweight (BMI ≥ 27 kg/m2 and < 30 kg/m2) with a weight-related comorbidity, and without T2D were randomized to receive RETA 1, 4, 8, 12 mg or placebo for 48 weeks. Lipids panel (including calculated non-HDL-C), apolipoproteins (apo) and NMR lipoprotein profiles were measured at baseline, 24 and 48 weeks in fasting plasma samples. Data were analyzed using a mixed model for repeated measures after log transformation. Results RETA dose-dependently reduced non-HDL-C up to 22.2% and 26.9% and apoB up to 19.6% and 24.2% at 24 and 48 weeks, respectively (Figure). At 48 weeks, RETA reduced TG and apoC-III levels up to 40.6% and 38.0%, respectively. RETA greatly reduced the total number of TG-rich lipoprotein particles (TRLP) and all subfractions of TRLP (large, medium and small) at 48 weeks (Table). Since the reduction in large and medium TRLP was greater than the reduction in small TRLP, the average size of TRLP was smaller following treatment with RETA. RETA reduced the number of total and highly atherogenic small LDL particles (LDLP), while total and small HDL particles (HDLP) were only slightly reduced. The average size of HDLP increased following treatment with RETA. At 48 weeks, the NMR-derived lipoprotein insulin resistance score was dose-dependently decreased by 27.4%, 31.7% and 32.5% with 4 mg, 8 mg and 12 mg, respectively, following RETA treatment. Conclusions RETA treatment for 48 weeks dose-dependently reduced levels of non-HDL-C and apoB and the number of total and small LDL particles, suggesting an improvement in atherogenic lipoprotein profile and cardiovascular risk in subjects who have obesity or overweight but not T2D.

Detection and analysis of ship emissions using single-particle mass spectrometry: A land-based field study in the port of rostock, Germany

The regulation of ship emissions has become more restrictive due to their significant impact on global air quality, particularly in coastal regions. According to the International Maritime Organization (IMO) regulations, current restrictions mainly limit the sulfur content of the fuel mass to 0.5 % and 0.1 % respectively. In compliance with these regulations, exhaust SO2 cleaning systems (scrubbers) and new low-sulfur fuels are increasingly used. For comprehensive monitoring of ship emissions, advanced measurement techniques are demanded. Our study reports on the results of a land-based field campaign conducted in the port of Rostock, Germany. The chosen location strategically positions the measurement setup to capture all incoming and outgoing ships passing within a distance of up to 2 km. Potential ship exhaust plumes are indicated by rapid changes in particle number and size distribution monitored by an optical particle sizer (OPS) and a scanning mobility particle sizer (SMPS). Additionally, single-particle mass spectrometry (SPMS) was used to qualitatively characterize ambient single-particles (0.2–2.5 μm) by their chemical signatures. In a one-week time span, the exhaust plumes of 73 ships were identified. The high sensitivity of SPMS to transition metals and polycyclic aromatic hydrocarbons (PAH) in individual particles make it possible to distinguish between different marine fuels.

Simultaneous qualitative and quantitative analysis for evaluating constituents of Atractylodis macrocephalae rhizome by UPLC-QTOF-MS

AbstractAtractylodis macrocephalae rhizome (AMR) belongs to medicine food homology. Its' clinical application of invigorating the spleen-stomach of AMR was applied to various diseases. In this research, a UPLC-QTOF-MS method was developed for qualitative and quantitative analysis of AMR, simultaneously. A Waters Acquity BEH C18 column (2.1 mm × 100 mm, 1.7 μm particle size) was used for separation of AMR multi-components. The column was eluted with a mobile phase of 0.1% formic acid-water and 0.1% formic acid-acetonitrile. Electron spray ionization with positive-ion mode and external standard method was utilized for quantifying the nine analytes in AMR. Constituents of AMR were scanned by UPLC-QTOF-MS and then identified by mass fragments and chromatographic information compared with the published literature and reference standards. Under positive mode, a total of 61 chemical compositions including 16 terpenoids, 8 polyacetylenes, 6 aromatics, 5 flavonoids, 5 coumarins, 5 organic acids, 4 amino acids, 3 fatty acids, 3 aliphatics, 2 steroids, and 2 alkenes, a nucleoside and an aldehyde were identified. Simultaneously, the contents of three amino acids (L-tyrosine, L-phenylalanine, and L-tryptophan), three sesquiterpenoids (atractylenolide Ⅲ, atractylenolide Ⅱ, and atractylenolide Ⅰ), a flavonoid (rutin), an organic acid (ferulic acid), and a pentacyclic triterpenoid (oleanolic acid) were determined in seventeen AMR batches. Amino acids and triterpenoid were quantified for the first time in AMR. The UPLC-QTOF-MS method developed in this article was reliable, practical, and useful for qualitative and quantitative evaluation of AMR multi-components.

Numerical investigations of heat transfer and pressure drop in packed bed duct exposed to forced convection boundaries under local thermal non-equilibrium conditions

The present study is a 2-D numerical study which discusses the thermohydraulic performance of packed bed duct under local thermal non-equilibrium and steady state conditions exposed to forced convection boundaries (BC-6). The numerical model is well validated with the experimental work reported in the literature and found to be accurate enough to perform further parametric investigations. The analysis is done to see the effect of different ball diameter (5 mm, 9 mm and 11 mm), bed porosity, heat transfer fluid (air, water and engine oil - Pr = 0.70–645) and ball material (EPS, steel and bronze) on heat transfer and fluid flow characteristics in turbulent flow region of Reynolds number ranging from 900 to 14,320. The numerical results obtained using commercial CFD software COMSOL shows that, the heat transfer coefficient and pressure drop in packed bed increases with increase in ball diameter, thermal conductivity of ball and bed porosity which is exactly reverse as reported in literature for BC-1 to BC-5. The maximum thermal performance factor with bronze particles is 2.45 and 24.5 times more than stainless steel and EPS particles respectively for larger particle size and bed porosity. Engine oil exhibits significantly higher heat transfer coefficient (9.7 × 105 W/m2K) and pressure drop (3.3 × 106 Pa) compared to water (40,126 W/m2K and 2028 Pa) and air (600 W/m2K and 250 Pa) respectively. Overall, the combination of water as heat transfer fluid along with bronze particles of larger diameter and larger bed porosity emerges as the optimal choice for enhancing heat transfer in the packed duct exposed to forced convection boundary condition BC-6.

ZIF‐67 Derived Cobalt Catalysts for the Hydroformylation of Liquid Olefins

AbstractIn this work, we described a general monometallic cobalt heterogeneous catalyst for the hydroformylation of olefins, achieving good yields and recyclability up to five times with no loss in catalytic activity. These catalysts were prepared through the pyrolysis of the well‐defined metal–organic framework ZIF‐67. The addition of steam during the pyrolysis did not affect the final phase composition of the cobalt particles; nonetheless, it resulted in an increase of the cobalt particle size and the partial removal of the carbonaceous matrix. The materials were extensively characterized by several techniques, and it was observed that the N‐doped carbon matrix played a crucial role in terms of activity and stability. Different liquid olefins, including internal, terminal, and cyclic were successfully tested in our hydroformylation protocol. Aldehydes yields of 48%–77% for different liquid olefins were achieved with the optimal catalyst. No leaching of the active sites was observed over five catalytic cycles. The high stability of the catalyst is attributed to the presence of stabilizing nitrogen atoms bearing the cobalt sites.

Preparation of Magnesium Titanate by Using Magnesium Chloride a Byproduct of Titanium Plant

This study explores the preparation of magnesium titanate using magnesium chloride, a byproduct of the titanium production plant as a precursor. The synthesis involves the reaction of MgCl2 with titanium tetrachloride under controlled thermal conditions. Initially, MgCl2 and TiCl4 are thoroughly mixed in stoichiometric proportions with an excess of oxalic acid solution to produce magnesium titanyl oxalate. The mixture is then subjected to a calcination process at temperatures ranging from 300 °C to 1000 °C in an oxygen-rich environment. The physicochemical properties of the synthesized MgTiO3 were analyzed using EDS, XRD, TG/DTA, SEM, and particle size analysis. This comprehensive set of analytical techniques provides a thorough understanding of the elemental, structural, thermal, morphological and physical characteristics of magnesium titanate. The formation of pure magnesium titanate is confirmed at temperatures above 800 °C, with lower temperatures leading to the presence of intermediate phases such as MgTi2O5. The synthesized MgTiO3 exhibits a homogeneous microstructure with well-defined grain boundaries, indicating successful preparation of the desired ceramic material.

Longevity of size-dependent particle removal performance of do-it-yourself box fan air filters.

Filtration performance of do-it-yourself (DIY) box fan filters deployed across a university campus was assessed over an academic year. Four DIY air filters were constructed from box fans and air filters with a minimum efficiency reporting value (MERV) of 13 and deployed in four spaces (two laboratories that include sources of particles and two offices). They were operated 9 hours daily with a programmable timer and were continuously monitored with power meters. Particle concentrations in the spaces were continuously monitored with low-cost nephelometers. The particle size dependent clean air delivery rate (CADR) and single pass filtration efficiency for each box was measured in a laboratory before deployment and every 10 weeks, for a total of five measurements over 40 weeks. We find that these DIY box fan filters maintain robust performance over time, with each air filter maintaining at least 60% of its initial CADR at the end of the 40 week study even with daily operation in environments with modest particle concentrations. CADR values for particles of 1.0-3.0 μm optical diameter averaged 34% higher than CADR values for 0.35-1.0 μm particles, aligning with MERV 13 filter size-dependent filtration expectations. Reductions in CADR over time were attributed to a reduction in filtration efficiency, likely due to a loss of filter electrostatic charge over time. There was no strong indication that increased resistance due to particle accumulation on filters appreciably decreased flow rates over time for any of the fans. The long-term robustness of DIY box fan air filters demonstrates their validity as a cost-effective, high performance, alternative to portable high efficiency particulate air (HEPA) filters.

Comparative Analysis of Milling Technologies in Dark and Milk Cocoa Topping Production for Ice Cream

Chocolate and cocoa toppings are widely used for confectionery products. Toppings used for ice creams contain higher fat content (about 40-60%) to ensure a greater flow to cover the whole product. The dark cocoa topping consists of cocoa and sugar powder distributed in vegetable fat, while cocoa topping with the added 7% non-fat milk fraction is regarded as a milk cocoa topping. This research aimed to determine and compare the impact of the ball mill, and five-roll mill and conching used for the production of dark and milk cocoa toppings regarding the particle size distribution, rheology properties and content of moisture, sucrose, fat and lactose. The obtained results showed that the volume-weighted mean parameter D (4,3) was lower in the samples produced in a ball mill. Additionally, the viscosity, linear and Casson, slightly increased in samples produced in a ball mill except for the milk cocoa topping which had 0.55 fold higher value of linear viscosity compared to the sample produced using a five-roll mill and conching. Regarding the results of NIR spectroscopy, it was found that the samples produced in a ball mill showed higher values of moisture, but lower values of sucrose, lactose and fat.

Comparative Analysis of the Strength of Concretes Made from Different Aggregates

The paper aimed to explore the replacement of river sand in concrete with iron fillings and sawdust at various percentages (10%, 20%, and 30%). The study used a 1:2:4 mix design and a water-cement ratio of 0.5. Wooden square cubes of dimensions 100 x 100 x 100 mm were employed, resulting in 42 concrete cubes. Tests were conducted to assess particle size distribution, specific gravity, bulk density, aggregate impact value, aggregate abrasion value, and compressive strength at 7th and 28th days of curing. Notably, after 7 days, compressive strength results showed that concrete with a 10% iron fillings replacement (18.5 N/mm²) had a higher average strength than concrete with 100% river sand (17.6 N/mm²). However, as the percentage of iron fillings increased to 20% (9.8 N/mm²) and 30% (7.1N/mm²), the compressive strength decreased. On the other hand, concrete with sawdust replacements at 10% (3.7 N/mm²), 20% (1.4 N/mm²), and 30% (0.5 N/mm²) exhibited significantly lower load-bearing capacity. These trends persisted at the 28th day, with the compressive strength decreasing with increasing percentages of iron fillings (10%: 20.3 N/mm², 20%: 11.2 N/mm², 30%: 11.6 N/mm²) and sawdust (10%: 3.4 N/mm², 20%: 2.3 N/mm², 30%: 1.4 N/mm²). The findings suggest that a low percentage of iron fillings can be used in combination with river sand to maintain load-bearing capacity, but sawdust or wood particles should be avoided as they adversely affect compressive strength. This research contributes valuable insights into the use of these materials in concrete mixtures.

The ApoB/LDL-C ratio predicts cardiovascular events in coronary artery disease patients independent of type 2 diabetes status

Abstract A high ApoB/LDL-C ratio reflects small LDL particle size which like type 2 diabetes (T2DM) is associated with insulin resistance. Whether the ApoB/LDL-C ratio and the presence of T2DM are mutually independent predictors of cardiovascular events is unclear and is addressed in the present study. We enrolled a large high-risk cohort of 1200 patients with coronary artery disease. T2DM was diagnosed according to current ADA guidelines. Prospectively, cardiovascular events were recorded over a mean follow-up period of 10.5±4.9 years. At baseline, the ApoB/LDL-C ratio was significantly higher in patients with T2DM (n=422) than in subjects who did not have T2DM (0.81±0.18 vs. 0.74±0.15 p<0.001). During follow-up, 662 patients suffered cardiovascular events. The Apo B/LDL-C ratio predicted cardiovascular events in univariate analysis (HR=1.11 [1.03-1.20] p= 0.006), and the event rate was higher in patients with than in those without T2DM (62.2% vs. 52.3%; p=0.001). In a multivariate adjusted Cox regression model both the ApoB/LDL-C ratio and T2DM significantly predicted cardiovascular events in a mutually independent manner, with standardized adjusted HRs of 1.11 [1.03-1.20]; p=0.008 and 1.39 [1.18- 1.64]; p<0.001, respectively. We conclude that in subjects with coronary artery disease the ApoB/LDL-C and T2DM are mutually independent predictors of cardiovascular events.

Size effect of ZIF-8 based nanocarrier pesticide delivery system on targeted release and insecticidal activity.

Traditional chemical pesticides are easily lost by surface runoff and only small quantities reach the target, thus causing serious environmental pollution. In this work, dinotefuran@zeolitic imidazolate framework-8@polydopamine@zein (DNF@ZIF-8@PDA@zein), was constructed to deliver DNF with pH and enzyme double response of release, thereby achieving targeted release and efficient long-term pest control. DNF@ZIF-8@PDA@zein was synthesized with three hydrated diameters (249.73 ± 9.99 nm, 142.94 ± 5.63 nm and 75.16 ± 4.66 nm, respectively). The release of DNF from DNF@ZIF-8@PDA@zein after 28 h was significantly higher at pH 5.0 (89.22 ± 7.18%) compared to that at pH 8 (81.8 ± 6.11%). Protease-assisted release of DNF was notably higher than that without protease (pH 5: 89.22 ± 5.55% versus 27.19 ± 3.22%; pH 8: 81.8 ± 6.11% versus 25.39 ± 3.87%). The stimuli-responsive release of DNF from DNF@ZIF-8@PDA@zein increased with decreased particle size due to increased pore size, reduced binding forces (i.e., weaker π-π stacking, hydrogen bonding, and Zn-N covalent bonding), and the shortening of diffusion path, leading to faster disintegration and drug release. Additionally, the anti-photolysis ability of DNF@ZIF-8@PDA@zein was 3.2 times that of pure DNF. The insecticidal activity improved with smaller nanoparticles due to higher drug release rate and greater inhibition of detoxification enzyme activity by more zinc ion (Zn2+) dissolution. The pH and enzyme dual-responsive release as well as insecticidal activity of DNF@ZIF-8@PDA@zein increase with decreased nanoparticle size, showing effective pest management in long-term and potential application prospects in sustainable agriculture. © 2024 Society of Chemical Industry.