Range Of Ratios Research Articles

MRNA delivery enabled by metal–organic nanoparticles

mRNA therapeutics are set to revolutionize disease prevention and treatment, inspiring the development of platforms for safe and effective mRNA delivery. However, current mRNA delivery platforms face some challenges, including limited organ tropism for nonvaccine applications and inflammation induced by cationic nanoparticle components. Herein, we address these challenges through a versatile, noncationic nanoparticle platform whereby mRNA is assembled into a poly(ethylene glycol)-polyphenol network stabilized by metal ions. Screening a range of components and relative compositional ratios affords a library of stable, noncationic, and highly biocompatible metal–organic nanoparticles with robust mRNA transfection in vitro and in mice. Intravenous administration of the lead mRNA-containing metal–organic nanoparticles enables predominant protein expression and gene editing in the brain, liver, and kidney, while organ tropism is tuned by varying nanoparticle composition. This study opens an avenue for realizing metal–organic nanoparticle-enabled mRNA delivery, offering a modular approach to assembling mRNA therapeutics for health applications.

Advanced design strategies and applications for enhanced higher-order multisegment denatured Pascal curve gears

The existing Pascal curve gears are limited by inflexible pitch curves and constrained transmission ratio changes, which hinders the application in a range of mechanical systems that require more adaptable gear solutions. To address this, a design procedure for higher-order multisegment denatured Pascal curve gear is proposed. A unified mathematical expression for the Pascal curve gear family is derived, enabling the construction of non-circular gears with free-form pitch curves by adjusting key parameters and offering more flexible pitch curve and a wider range of transmission ratios. Compared with elliptical gears and eccentric circular gears, its transmission ratio range can be expanded by up to 35%. Then the transmission characteristics of these gears are analyzed in detail. To validate the design, the visual analysis and design software of the gear is compiled based on Visual Basic, and is verified with the example. The novelty Pascal curve gears is applied to drive the differential velocity vane pump. The displacement, instantaneous flow rate, and pulsation rate of the differential velocity vane pump are calculated. The comparison with the differential pumps driven by eccentric non-circular gears and Fourier non-circular gears shows that when the pitch curves are not concave, the displacement driven by Pascal curve circular gears is the highest (compared to differential pumps driven by eccentric non-circular gears, and Fourier non-circular gears, their flow rates increased by 50.6%, and 175.7%, respectively), and the instantaneous flow pulsation rate of single pump is the smallest.This study shows that the higher-order multisegment denatured Pascal curve gear provides a viable solution for systems requiring flexible transmission mechanisms and improved operational performance.

Accurately measuring slowly propagating flame speeds: Application to ammonia/air flames

Environmental concerns have driven the development of alternative fuels and refrigerant working fluids with low global warming potential. Ammonia (NH3) is a potential zero-carbon fuel, while hydrofluorocarbons (HFCs) like R-32 and R-1234yf are being adopted as refrigerants. When mixed with air, these compounds can sustain slowly propagating flames with laminar flame speeds less than 10 cm/s. Unlike typical hydrocarbon-fueled flames, these slow flames are influenced by buoyancy-induced flow and radiation heat loss. In this study, we experimentally investigate the flame speeds of NH3/air mixtures using the constant-pressure spherically expanding flame method, while circumventing gravity-induced natural convection, and account for radiation-induced inward flow. To mitigate buoyant convection, a low-cost drop tower was built and used to study slow spherically expanding flames in free fall. A computational model (SRADIF) is utilized that combines thermodynamic equilibrium and finite rate optically thin limit radiation heat loss calculations to estimate the inward flow. The developed methodology is utilized to investigate slowly propagating NH3/air flames over a range of equivalence ratios. A systematic approach was undertaken to understand and quantify the errors that could arise when deriving the laminar flame speed. It was found that attempting to study slowly propagating flames in a static configuration, as opposed to in free fall, results in large differences in flame dynamics and subsequently all derived quantities. It is necessary to study slowly propagating flames in free-fall. Additionally, using experimental data that has not been corrected for radiation-induced flow leads to large errors in all derived quantities. Furthermore, direct comparisons of experimental measurements and detailed flame simulations are found to be necessary to determine if existing extrapolation approaches are applicable to these slowly propagating flames, which are challenging to study.

Experimental Determination of a Mixture Composed of Camisea Natural Gas and CO2 Laminar Burning Velocity

The aim of this work is to provide new experimental data on laminar burning velocities for a new synthetic mixture composed of Camisea natural gas and CO2. It was found that the relevant published experimental background data are l imited to mixtures composed of methane and CO2; considering the fact that Camisea natural gas is widely used in Peru, this experimental research will serve as a supportive resource for further experimental and industrial implementations in this country, such as the design and modeling of new engines or industrial burners that are designed to be fueled by this mixture. An experimental setup for analyzing three types of flame geometry, which is feasible to implement for a wide range of conditions, was built in PUCP PI0735 laboratory and all the measurements were obtained for a range of mixtures (0%, 21.2%, 28.5%, 38.9%, 50% CO2) and ratios from around 0.55 to 0.95 at atmospheric conditions. The laminar burning velocities results obtained were analyzed in groups based on %CO2. In addition, the experimental margin error was determined by considering all the sources. The following conclusions were reached: (1) The laminar burning velocity decreases with the increase in CO2 percentage in the mixture due to the CO2 decreasing the flame temperature effect. (2) The flat flame type provided the highest value of burning velocity for each group of CO2 percentage in which it appears. (3) The highest obtained laminar burning velocity value was 22.64 ± 0.15 cm/s, for a flat flame with a ratio of 0.72 and 29.98% of CO2, while the lowest obtained value was 6.78 ± 0.15 cm/s for a conical trunk flame with a ratio of 0.59 and 49.83% of CO2. (4) The highest evaluated CO2 percentage was 50.97% for a conical trunk flame with a ratio of 0.69 and a burning velocity value of 11.04.

Near-Field Mixing in a Coaxial Dual Swirled Injector

AbstractImproving mixing between two coaxial swirled jets is a subject of interest for the development of next generations of fuel injectors. This is particularly crucial for hydrogen injectors, where the separate introduction of fuel and oxidizer is preferred to mitigate the risk of flashback. Raman scattering is used to measure the mean compositions and to examine how mixing between fuel and air streams evolves along the axial direction in the near-field of the injector outlet. The parameters kept constant include the swirl level $$S_e = 0.67$$ S e = 0.67 in the annular channel, the injector dimensions, and the composition of the oxidizer stream, which is air. Experiments are carried out in cold flow conditions for different compositions of the central stream, including hydrogen and methane but also helium and argon. Three dimensionless mixing parameters are identified, the velocity ratio $$u_e/u_i$$ u e / u i between the external stream and internal stream, the density ratio $$\rho _e/\rho _i$$ ρ e / ρ i between the two fluids, and the inner swirl level $$S_i$$ S i in the central channel. Adding swirl to the central jet significantly enhances mixing between the two streams very close to the injector outlet. Mixing also increases with higher velocity ratios $$u_e/u_i$$ u e / u i , independently of the inner swirl. Additionally, higher density ratios $$\rho _e/\rho _i$$ ρ e / ρ i enhance mixing between the two streams only in the case without swirl conferred to the central flow. A model is proposed for coaxial swirled jets, yielding a dimensionless mixing progress parameter that only depends on the velocity ratio $$u_e/u_i$$ u e / u i and geometrical features of the swirling flow that can be determined by examining the structure of the velocity field. Comparing the model with experiments, it is shown to perform effectively across the entire range of velocity ratios $$0.6 \le u_e/u_i \le 3.8$$ 0.6 ≤ u e / u i ≤ 3.8 , density ratios $$0.7 \le \rho _e/\rho _i \le 14.4$$ 0.7 ≤ ρ e / ρ i ≤ 14.4 , and inner swirl levels $$0.0 \le S_i \le 0.9$$ 0.0 ≤ S i ≤ 0.9 . This law may be used to facilitate the design of coaxial swirled injectors.

An Experimental Investigation into Ammonia Oxidation and NOx Emission in a Packed-Bed of Quartz Particles

ABSTRACT The effect of temperature, initial NH3 concentration, equivalence ratio, and flowrate on the characteristics of ammonia (NH3) oxidation and associated NOx formation in a fixed-bed reactor packed with quartz particles has been systematically investigated with a stream of NH3 and O2 in He over a range of furnace set temperatures (900 K – 1400 K), initial NH3 concentrations (2% – 10%), equivalence ratios (ɸ = 0.8, 0.9, 1.0, 1.1), and total flowrates (145 mL/min, 289 mL/min, and 434 mL/min). Benchmark flow reactor experiments, without the quartz particles in the reactor under otherwise similar conditions, were previously performed and served as a reference case for this work. Compared to the flow reactor results, the packed-bed data indicated a lower reaction onset temperature and more gradual NH3 conversion across the temperature range. Both packed-bed and flow reactor experiments indicated that decreasing flowrate, thus increasing residence time, resulted in greater NH3 conversion. NH3 conversion in the fixed-bed reactor was similar for all equivalence ratios at temperatures ≤1200 K, above which NH3 conversion increased with decreasing equivalence ratio, a trend broadly aligned with previous flow reactor experiments. For all conditions examined, NO was the major NOx component and NO2 was insignificant. Across the range of equivalence ratios, NO emission was low, yet noticeable, from 900 K – 1100 K, before spiking at 1200 K. Above 1200 K, NO emissions decreased before drastically increasing again at 1400 K under fuel-lean conditions. At temperatures ≤1300 K, NO was generally found to decrease with decreasing equivalence ratio, while at 1400 K, NO increased with decreasing equivalence ratio. NO emissions were significantly lower in the packed-bed compared to the flow reactor scenario at temperatures ≥1300 K.

Association of Perceived Neighborhood Disorder with Substance Use Behaviors and Retail Access Among Southern California Adolescents.

Neighborhood disadvantage is associated with a higher concentration of tobacco, cannabis and alcohol retailers and greater risk of certain substance use behaviors among youth. Less is known about the impact of subjective neighborhood disorder, which captures distinct exposures that may be relevant to substance use outcomes, including neighborhood social processes, safety, physical characteristics, and neighborhood drug use. Data are from two waves (Feb-Dec 2022) of a prospective cohort of Southern California high school students (n = 2,139; mean[SD] age = 15.7.[0.6]). We examined associations of perceived neighborhood disorder at baseline with (a) perceived ease of purchase (continuous scale 0-100) for alcohol, cannabis, e-cigarettes, cigarettes, hookah, cigars/cigarillos, and oral nicotine at baseline and follow-up, and (b) repeated measures of past 6-month and past-30-day alcohol, vaped cannabis, smoked cannabis, cannabis edibles, e-cigarette, cigarette, cigarillo, hookah, and oral nicotine use. E-cigarettes were perceived to be the easiest product to purchase. Participants in the highest (vs. lowest) quartile of neighborhood disorder reported greater mean ease of purchasing scores for all products (mean difference range = 5.43 [95%CI: 1.64-9.21] for mint/menthol oral nicotine products to 9.40 [95%CI: 6.16-12.64] for hookah) and greater odds of e-cigarette, smoked cannabis, edibles, vaped THC, and alcohol use (odds ratio range = 1.52 [95%CI: 1.05 to 2.18] for past 6-month alcohol to 5.40 [95% CI: 3.46 to 8.42] for 30-day smoked cannabis). Interventions that shape youth perceptions of their neighborhood and reduce youth retail access in disadvantaged neighborhoods are needed and may help to prevent youth substance use.

Laminar burning velocity of ethanol-ethyl acetate mixtures in air

Alcohols, esters, and their mixtures are ubiquitous in the process industry. However, safety data remain limited, especially for mixtures. In this work, the laminar burning velocity, Sl, of ethanol-ethyl acetate mixtures in air was investigated (at 90 °C and atmospheric pressure) through computations performed using three different detailed chemical kinetic mechanisms, and measurements obtained from pressure time histories recorded during closed vessel explosion experiments. Computations were run varying the equivalence ratio, φ, from 0.6 to 1.7, and the mole fraction of ethanol in the fuel mixture from 0 (only ethyl acetate) to 1 (only ethanol). For all systems, explosion experiments were carried out at φ = 1.1, i.e., the composition at which, according to calculations, Sl achieves its maximum value. Regardless of the kinetic mechanism, reasonable agreement is found between computed and experimental data, including experimental data retrieved from the literature for ethanol and ethyl acetate. Results show that the behavior of ethanol-ethyl acetate is bounded between the behaviors of ethanol and ethyl acetate, approaching the former/latter as the mixture is enriched in ethanol/ethyl acetate. Over the whole range of equivalence ratios explored, the values of Sl for ethanol-ethyl acetate are smaller than those obtained by averaging the corresponding values of ethanol and ethyl acetate according to their mole proportions in the fuel mixture. This is also confirmed experimentally. A simple Le Chatelier’s mixing rule-like formula is proved to predict values of Sl that closely match both computed and experimental data, suggesting that the nature of the interaction between ethanol and ethyl acetate is predominantly thermal rather than chemical.

Highly-selective and well-effective removal of cesium ions by segregative titanium-ferrocyanide/chitosan melamine sponge composite

Selectively and efficiently removing Cs is of great urgency and challenge for the treatment of radioactive wastewater. In this work, titanium-ferrocyanide/chitosan melamine sponge composite (TFCM) was synthesized by cross-linking and titanium-doping strategy, and employed to remove Cs+ from water. The obtained TFCM exhibited excellent adsorption performance for Cs+, due to its porous and 3D skeleton structure. The TFCM demonstrated a broad range of pH (pH = 3–11) suitability and high removal ratio of Cs+. The adsorption behavior of TFCM on Cs+ conformed to the Langmuir adsorption process and pseudo-second-order kinetics model. Remarkably, TFCM displayed a high selectivity in Cs+ adsorption with the presence of other cationic (K+, Na+, Ca2+, Mg2+). TFCM could easily be separated from water because of loading on the melamine sponges. Besides, the TFCM could maintain more than 78.1 % removal ratio of Cs+ after five adsorption-desorption cycles. Furthermore, the concentration of Cs+ could decrease to 10 μg/L from 20 mg/L with a prominent removal ratio of 99.95 %. Characterization results revealed that the adsorption process of Cs+ by TFCM was dominated by ion-exchange. In summary, the TFCM is a high selectivity, efficiently and easily separable adsorbent with excellent application prospects for removing Cs from radioactive wastewater.

Impact of density ratio on droplet dynamics in pulsating flow

Secondary atomization is extensively studied by investigating a droplet subjected to a steady air/gas stream. However, droplets are often subjected to unsteady or pulsating flows, such as in aero-engines or rockets, because of thermo-acoustic instabilities in the combustion chambers. The investigation focuses on the droplet dynamics and breakup in a pulsating flow for a range of density ratios (ρr), 1000 to 10, under sinusoidal airflow of different amplitudes and frequencies as compared to the dynamics in a steady flow. The volume of fluid multiphase model tracks the liquid–gas interface, and the governing equations are solved using the finite volume method. The two-dimensional axisymmetric pulsating simulations demonstrate accuracy comparable to the corresponding three-dimensional simulations at a much lower computational cost and are used for parametric studies. The droplets under the pulsating flow show a wavy surface, and larger vortex structures are observed during the deceleration period. At a high-density ratio (1000), pulsating flow enhances droplet deformation for a faster breakup, with the flow amplitude having more impact than its frequency. For a medium-density ratio (100), where breakup occurs under steady flow, droplet breakup is inhibited in the pulsating flow at low amplitude and high frequency. In the case of a low-density ratio (10), there is no breakup under steady flow, but pulsating flow promotes breakup, except at low amplitude and high frequency. The droplet breakup is always achieved for the highest amplitude, while lower frequencies push the liquid mass from the center of the droplet to the rim.

Post mortem chiral analysis of MDMA and MDA in human blood and hair

Drug-related fatalities in the EU are predominantly associated with opioids. MDMA (Ecstasy) consumption results in fewer lethal intoxications despite its widespread use. This study investigates MDMA-related fatalities, focusing on enantiomer ratios of MDMA and its metabolite MDA to explore the role of metabolism in fatal outcomes.MDMA induces euphoria, increased empathy, and physiological effects such as tachycardia, hypertension, and hyperthermia. Metabolism mainly involves CYP1A2 and CYP2D6, with polymorphism of the latter influencing metabolism rates. Our institute observed several MDMA-related fatalities, which prompted an investigation into the potential role of inefficient drug metabolism in these cases.A novel quantitative chiral analysis method was developed and validated for MDMA, MDA, amphetamine and methamphetamine enantiomers in human blood. Analysis of post mortem blood samples from eleven MDMA-related fatalities exhibited a wide range of concentrations and enantiomer ratios. Variability in R/S MDMA ratios, however, could be linked to the time period of metabolism. Hair analysis revealed high MDMA concentrations in all segments, irrespective of prior drug abuse anamnesis. Therefore, hair analysis may not be suitable for the assessment of past drug use in ecstasy-related fatalities.The results indicated that elevated levels of the MDMA enantiomer are correlated with longer survival times in cases of intoxication. However, there was no clear evidence for slowed MDMA metabolism as a cause of lethal intoxications. While challenges remain due to the diversity of cases, this study contributes valuable insights into ecstasy intoxications, aiding future interpretation of post mortem analysis.

The global flow state in a precessing cylinder

We examine the fluid flow forced by precession of a rotating cylindrical container using numerical simulations and experimental flow measurements with ultrasonic Doppler velocimetry. The analysis is based on the decomposition of the flow field into contributions with distinct azimuthal symmetry or analytically known inertial modes and the corresponding calculation of their amplitudes. We show that the predominant fraction of the kinetic energy of the precession-driven fluid flow is contained only within a few large-scale modes. The most striking observation shown by simulations and experiments is the transition from a flow dominated by large-scale structures to a more turbulent behaviour with the small-scale fluctuations becoming increasingly important. At a fixed rotation frequency (parametrized by the Reynolds number, $Re$ ) this transition occurs when a critical precession ratio is exceeded and consists of a two-stage collapse of the directly driven flow going along with a massive modification of the azimuthal circulation (the zonal flow) and the appearance of an axisymmetric double-roll mode limited to a narrow range of precession ratios. A similar behaviour is found in experiments which make it possible to follow the transition up to Reynolds numbers of $Re\approx 2\times 10^6$ . We find that the critical precession ratio decreases with rotation, initially showing a particular scaling ${\propto }Re^{-({1}/{5})}$ but developing an asymptotic behaviour for $Re\gtrsim 10^5$ which might be explained by the onset of turbulence in boundary layers.

Development of a complex antioxidant for stabilization of dressing enriched with omega-3 fatty acids

The solution to the problem of developing a complex antioxidant for the oxidative stabilization of emulsion systems with a high content of ω-3 polyunsaturated fatty acids (PUFAs) is considered. The object of the study is the oxidative stabilization of dressing using a complex antioxidant of plant origin. The ratio of ω-3:ω-6 PUFAs in model samples of the emulsion system was 1:5.46 and 1:2.21. The reasonable range of antioxidant ratios in the complex was substantiated. The ratio of tocopherol extract, garlic and laurel essential oils in the complex antioxidant is 1:1:1, respectively. Over 30 days of storage of the emulsion system model samples stabilized with a complex antioxidant, there is a gradual accumulation of organic acids (from 0.73 % to 0.75 %). The content of primary oxidation products increases for sample No. 2 – from 0.7 to 1.9 mmol ½ O2/kg, for sample No. 3 – from 0.4 to 1.2 mmol ½ O2/kg. The obtained values of physicochemical parameters meet the requirements of regulatory documentation (DSTU 4561). The peculiarity of the obtained results is that the complex antioxidant showed a significant increase in the stability of the emulsion system of high nutritional value, in particular, slowed down the accumulation of organic acids and peroxides. From a practical point of view, the development can effectively stabilize food emulsion systems with a high content of oxidation-labile PUFAs. An applied aspect of the obtained scientific result is the possibility of modeling and developing new formulations of emulsion and individual fat systems with high nutritional value, containing high PUFA concentrations

Performance of a Small Hydrodynamic Journal Bearing Involving Adsorbed Layer and Surface Elastic Deformation

The load and friction performances of a small elastohydrodynamic journal bearing with the shaft radius 1mm have been computationally studied. The effect of the adsorbed layer is incorporated and the multiscale hydrodynamic flow theory is used. It is shown that the multiscale performance of this bearing occurs in the wide eccentricity ratio range from 0.3 to nearly unity because of the influence of the adsorbed layer, and thus the generated pressures and carried load of this bearing are significantly greater than the classical hydrodynamic theory calculations. The effect of the adsorbed layer is more stronger for rigid bearing surfaces than for elastic bearing surfaces especially for a strong fluid-bearing surface interaction, and it is strong for the high eccentricity ratios over 0.9. In this bearing, when the effect of the adsorbed layer is incorporated, the friction coefficients on both bearing surfaces are reduced in the wide eccentricity ratio range as compared to the classical calculation; Stronger the fluid-bearing surface interaction, greater the reduction of the friction coefficient, showing the pronounced non-continuum effect of the adsorbed layer. However, for elastic surfaces the friction coefficient is a bit higher than that for rigid surfaces especially for high eccentricity ratios and strong fluid-bearing surface interactions.

An observational study of lower limb muscle imbalance assessment and gait analysis of badminton players

PurposeThe imbalance of muscle strength indicators has a negative impact on players. Lower limb muscle imbalance can cause gait abnormalities and increase the risk of muscle injury or decreased performance in significantly asymmetrical situations. This study aims to assess the lower limb muscle imbalance and gait feature between the dominant and non-dominant sides of badminton players and the associations between the two variables.MethodsThe study included 15 badminton players with years of training experience. Muscle strength and gait parameters were obtained from isokinetic muscle strength testing and plantar pressure analysis systems. The symmetry index was calculated based on formulas such as plantar pressure distribution and percentage of plantar contact area.ResultsIn the isokinetic muscle strength test, significant differences were found in bilateral knee flexors’ average power and total work at 60°/s angular speed. The hamstring to quadriceps ratio (H/Q) range of knee joints of the dominant and non-dominant sides is 0.63–0.74 at low speed, while the H/Q range is 0.81–0.88 at fast speed. The H/Q of bilateral knees increases with increasing angular velocity. As the angular velocity increases, the peak torque to body weight ratio (PT/BW) of the participants’ bilateral knee flexors and extensors shows a decreasing trend. The asymmetry score of H/Q at 180°/s angular speed is positively related with step time and stance time. There are varying degrees of differences in gait staging parameters, plantar pressure in each area, plantar contact area, and symmetry index between the dominant and non-dominant sides of badminton players when walking.ConclusionBadminton players have weaker flexors of the knee joint, imbalanced muscle strength in flexors and extensors, decreased lower limb stability, and a risk of knee joint injury on the non-dominant side. The bending and stretching strength of the knee joint on the dominant side of the players is greater than that on the non-dominant side. The pressure in the first metatarsal region of the dominant side is higher, while that in the midfoot and heel regions is higher on the non-dominant side. badminton players have better forward foot force and heel cushioning ability. Long term badminton sports result in specialized changes in plantar pressure distribution and reduced symmetry.

What is the optimal range of fasting stress hyperglycemia ratio for all-cause mortality in American adults: An observational study.

To date, no studies have been conducted to assess the impact of fasting stress hyperglycemia ratio (SHR) on all-cause mortality. Therefore, the objective of our study is to investigate the association between SHR and all-cause mortality in a population of American adults. The study population was derived from NHANES data spanning from 2005 to 2018. The exposure variable SHR was derived from fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c%), and the specific calculation formula was as follows: (FBG (mmol/L))/(1.59 × HbA1c (%) - 2.59). The outcome variable was all-cause mortality. A total of 18,457 participants were enrolled in this prospective cohort study. Following a median follow-up period of 90 months, all-cause mortality was observed in 10.32% of the subjects. Cox proportional hazards regression model indicates that there is no significant difference between SHR and all-cause mortality in the fully adjusted model, whether analyzed as a continuous or categorical variable (P for trend > 0.05). Through the 2-piecewise Cox proportional hazards regression model, we have determined that the inflection point of SHR in relation to all-cause mortality is 0.88. It has also been observed that when the value of SHR is on the left side of the inflection point (SHR ≤ 0.88), there is a significant 77% (HR: 0.23; 95% CI: 0.10-0.50) reduction in all-cause mortality for each additional unit increase in SHR. Conversely, when the value of SHR exceeds 0.88, there is a substantial 2.40-fold (HR: 2.40; 95% CI: 1.61-3.58) increase in the risk of all-cause mortality (P for log likelihood ratio test < .001). The subgroup analysis results demonstrate that sex has the potential to modify the association between SHR and all-cause mortality within the population exhibiting SHR ≤ 0.88. The relationship between SHR and all-cause mortality follows a U-shaped pattern, where in the lowest risk of death for the average American adult is observed at an SHR value of 0.88. Furthermore, in men with SHR ≤ 0.88, there is a significant inverse relationship between the increase in SHR and the risk of all-cause mortality.

Incidence of symptomatic discoid meniscus in Korea: epidemiologic big data analysis from HIRA database

BackgroundThere is a lack of evidence of the diagnosis and treatment-related epidemiological studies of symptomatic discoid meniscus. This study analyzed the national epidemiological data for discoid meniscus in South Korea.MethodsFrom 2011 to 2019, data related to the diagnosis and procedure codes of discoid meniscus were obtained from the Korean Health Insurance Review and Assessment Service database. All patients encoded as discoid meniscus were included. Data were extracted and further analyzed as follows: (1) the total number and the incidence (cases per 100,000) of discoid meniscus diagnosis per year, (2) sex distribution, (3) age distribution, (4) discoid meniscus ratio (total discoid meniscus coding per total meniscus injury coding), and (5) surgical procedures after discoid meniscus injury.ResultsThe total number of discoid meniscus diagnosed was 4576 in 2011 and increased to 6639 in 2019, representing a 45.1% increase. The incidence was 9.5 in 2011 and increased to 13.0 in 2019. Concerning sex, discoid meniscus was more common in females (55%) than in males (45%) over the study period. Regarding age, the peak age of discoid meniscus in 2011 was “under 19,” whereas in 2019, the peak age was observed in the 50s. The discoid meniscus ratio range was 2.12–2.60% from 2011 to 2019. The total number of meniscectomy increased by 20% from 2000 in 2011 to 2475 in 2014. However, the total number of meniscus repairs was 318 in 2011 and increased to 502 in 2019, indicating an increase of 58%.ConclusionsThe total number and incidence of symptomatic discoid as well as the discoid meniscus ratio and the incidence of total discoid meniscus repair steadily increased from 2011 to 2019. The number of meniscus repair procedures increased more rapidly than that of meniscectomy. The current study helps understand the epidemiology of symptomatic discoid meniscus, its prevention, and cost-saving measures in South Korea.

Influence of Aqueous Phase Salt and Oil Phase Surfactants and Viscosity on the Dynamic Interfacial Tension and Coalescence Timescales.

Liquid-liquid separation is a critically important process in the treatment of emulsions that can occur in our environment, such as oily stormwater, shipboard bilgewater, or off-shore oil spill treatment. Effective filtration systems, including coalescing filters, are essential for mitigating these environmental pollutants. Achieving this requires a comprehensive understanding of liquid-liquid interface dynamics influenced by additives and surfactants. Furthermore, understanding the impact of surfactants on emulsion stability in saline environments is vital for optimizing filtration processes and ensuring the protection of marine and freshwater ecosystems. In this work, these effects are highlighted using measurements performed across a range of droplet size, surfactant concentration, viscosity ratios, and saline presence. Dynamic IFT measurements are conducted using the pendant drop method for water in light mineral oil, with and without salt in the water phase. The effect of salt addition is also highlighted by using microfluidic coalescence experiments, in which it was found that the addition of salt increases the dimensionless drainage time below the critical micelle concentration. The second focus of this work is to study the effect of bulk phase viscosity on the stability. Dynamic IFT measurements are performed at both millimeter and micrometer scales using pendant drop experiments and microfluidic tensiometry, respectively, involving light and heavy mineral oils with varying SPAN80 surfactant concentrations. The surfactant diffusivity and interfacial adsorption and desorption rates are then extracted by fitting a surfactant diffusion and equation of state equations to the dynamic IFT measurements. The results of the IFT decay, surfactant diffusivity, and adsorption rates are compared at two different viscosity ratios. This study also compares the times required for IFT relaxation with the film drainage times in water-in-oil systems. The comparison aids in comprehending the impact of competing timescales during film drainage. The findings presented in this paper offer valuable insights into the design and optimization of liquid-liquid filtration systems, especially when operating under challenging environmental conditions, such as in saline environments. The principles explored here can be applied to improving industrial water treatment and in the design of advanced filtration technologies for chemical and petrochemical industries, particularly those involving flow, contributing to more sustainable and efficient practices in handling emulsified waste streams.

High-Entropy Magnet Enabling Distinctive Thermal Expansions in Intermetallic Compounds.

The high-entropy strategy has gained increasing popularity in the design of functional materials due to its four core effects. In this study, we introduce the concept of a "high-entropy magnet (HEM)", which integrates diverse magnetic compounds within a single phase and is anticipated to demonstrate unique magnetism-related properties beyond that of its individual components. This concept is exemplified in AB2-type layered Kagome intermetallic compounds (Ti,Zr,Hf,Nb,Fe)Fe2. It is revealed that the competition among individual magnetic states and the presence of magnetic Fe in originally nonmagnetic high-entropy sites lead to intricate magnetic transitions with temperature. Consequently, unusual transformations in thermal expansion property (from positive to zero, negative, and back to near zero) are observed. Specifically, a near-zero thermal expansion is achieved over a wide temperature range (10-360 K, αv = -0.62 × 10-6 K-1) in the A-site equal-atomic ratio (Ti1/5Zr1/5Hf1/5Nb1/5Fe1/5)Fe2 compound, which is associated with successive deflection of average Fe moments. The HEM strategy holds promise for discovering new functionalities in solid materials.

Study on the Properties of All-Solid Waste Fluidized Filling Materials Applied to Mine Void Area Filling Engineering

The extraction of mining resources, as well as processing processes such as ore beneficiation and smelting, generate large amounts of tailings that are difficult to directly utilize. Meanwhile, substantial filling materials are required for the voids formed after mining operations, and the environmental issues and safety hazards brought on by massive solid waste disposal cannot be ignored. By utilizing solid waste with alkaline and pozzolanic activity as the binder component and gold tailings as filler aggregate to prepare filler material to fill up the void areas, the purpose of waste treatment can be achieved. In this study, salt sludge, steel slag, ground granulated blast furnace slag, and gold tailings were used to prepare all-solid waste fluidized filling material for filling mine void areas, which not only solves the engineering safety problem of easy collapse of the mine airspace in the mining process but also ensures a backfill effect with high strength, which continuously guarantees the uninterrupted progress of the mining project. At the same time, the preparation of fluidized materials can consume a large amount of tailings and other solid waste, solving the problem of their stockpiling. The components of the solid wastes used are all general industrial solid wastes, so the preparation of the fluidized materials will not have an impact on the surrounding environment. The effects of binder ratios on the workability of the filling materials were investigated by means of the slump and slump flow tests. Combined with the unconfined compressive strength test, the change in backfill material strength with curing age and the water–binder ratio was studied. The experimental results showed that the slump and slump flow value of the filling material were positively correlated with the water–binder ratio. The water–binder ratio range satisfying a slump value of 180~260 mm and a slump flow value not less than 400 mm was 0.95~1.106. However, the strength decreased with the increase in the water–binder ratio, conforming to a hyperbolic relationship. The all-solid waste fluidized filling material had strengths not less than 0.22, 1.09, and 1.95 MPa at 3, 7, and 28 d, respectively, meeting the workability requirements. Finally, a method for determining the optimal range of water–binder ratio considering both workability performance and strength is proposed based on the relationship between slump value, slump flow value, unconfined compressive strength, and the water–binder ratio.