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This study examined the effects of spread formulation and the structural/lubricant properties of six different commercial hazelnut and cocoa spreads on sensory perception. Rheology, tribology, and quantitative descriptive analysis (QDA) was assessed by also evaluating the correlation coefficients between the quality descriptor and the rheological and textural parameters. The viscosity was evaluated at different temperatures to better simulate conditions before and after ingestion. Tribological analysis was executed at 37°C to mimic the human oral cavity. The effect of saliva presence and the number of runs on tribological behaviors was investigated. Moreover, textural, calorimetric, and particle size distribution measurements were performed to reinforce the correlation between structural/thermal parameters (e.g., firmness, stickiness, sugar melting point) and sensory aspects. "Visual viscosity," defined as a sensory attribute evaluated prior to consumption, negatively correlated with apparent viscosity measured at 20°C and 10 s−1, whereas "body," defined during oral processing and related to creaminess, positively correlated with apparent viscosity measured at 37°C and 50 s−1. These attributes were mainly influenced by particulate microstructure and solid volume fraction within the formulation. Textural stickiness positively correlated with sensory "adhesiveness" and was related to fat composition and milk powder addition, while "sweetness" was related to sucrose content and sugar melting enthalpy. Tribological data provided meaningful information related to particle‐derived attributes, as well as after‐coating perception (fattiness/oiliness), thus better predicting food evolution during oral consumption. [ABSTRACT FROM AUTHOR]

In the present study, a phenolic extract derived from the Pimpinella affinis plant underwent nanoencapsulation. The nanoencapsulation process employed chitosan, Salvia macrosiphon gum (SMG), and a chitosan–SMG complex (1:1) (CCS) as coating agents. The evaluation of nanoemulsions encompassed measurements of particle size, polydispersity index (PDI), ζ‐potential, encapsulation efficiency, and intensity distribution parameters. The overall results of these assessments indicated that the nanoemulsion coated with CCS exhibited the most favorable characteristics when compared to other treatments. Subsequently, this specific nanoencapsulated sample was utilized to enhance the oxidative stability of canola oil at concentrations of 100, 200, and 300 ppm (parts per million). Oxidative stability tests, assessed through the total oxidation value (TOTOX) index, highlighted the superior performance of the nanoencapsulated extract, particularly at a concentration of 300 ppm. This enhancement can be attributed to the increased release of phenolic compounds from the CCS coating into the canola oil. The findings illustrate that the nanoencapsulation process can significantly enhance the efficacy of P. affinis extract in improving the oxidative stability of canola oil. [ABSTRACT FROM AUTHOR]

Soft tissues, such as muscle could autonomously grow through re‐alignment and/or ‐combination of collagen nanofibrils upon the mechanical training. This adaptive capability is highly expected in artificial materials, particularly in hydrogel actuator. In order to avoid the failure for devices by suffering from the accumulated mechanical loading, in this work, a double layered thermo‐responsive hydrogel actuator capable of self‐strengthening was successfully prepared. In the bilayer, PVA nanocrystals with different particle sizes were uniformly distributed in each monolayer matrix, giving rise to the asymmetric structure and the resultant differentiated de‐swelling behaviors. Thus, the obtained hydrogel actuator with the semi‐interpenetrating network of P(NIPAM‐co‐NMA) can display diverse programmable transformations by varying the temperatures. The existence of PVA nanocrystals in both layers not only can enhance the mechanical strength, dramatically minimizing the collapse of hydrogel actuator in service due to the imbalance of the mechanical properties for bilayer structure, but also was greatly involved in the self‐reinforcing behavior. After repetitive tensile training with 80% strain, the tensile strength and fracture strain increased from 29.6 to 45.8 kPa and 95% to 104%, respectively. The experimental results indicated that the anisotropic orientation and strain‐induced‐crystallization for PVA crystalline domains readily occurred along the tensile direction, finally leading to the synchronous enhancement in mechanical strength for both layers. This work provides a new strategy for designing smart and robust biomimetic hydrogel systems that can be further used as the intelligent soft robotics in various fields. [ABSTRACT FROM AUTHOR]

The leaf‐cutter ant Atta sexdens is crucial in ecological balance and economic activities, due to its contribution to the aeration and accumulation of organic matter in the soil, but it may also be an agricultural pest when it defoliates plants for the fungus growth used as a food source. This leaf‐cutter ant exhibits a polymorphic worker caste system with distinct activities in the colony. These functions are performed by workers classified into subcastes, including gardeners, which are responsible for the fungus and brood care; cleaners (waste removers), which remove wastes; foragers, which collect and transport plant parts to the nest; and soldiers, which are responsible for colony defence and the support of foraging activities. In our previous work, we showed that A. sexdens has five types of circulating haemocytes in the haemolymph, which play a vital role in immune defence. Herein, we further investigated the population profile of circulating haemocytes in the haemolymph of different worker subcastes of A. sexdens using flow cytometry. Each subcaste exhibited a single population of haemocytes in the haemolymph. However, a detailed 3D dispersion analysis uncovered five distinct haemocyte subpopulations, two of which presented higher quantities. The soldier displayed haemocytes with high fluorescence intensity, compared with the gardener, waste remover, and forager, along with increased complexity, compared with the gardener subcaste. These results suggest that these cells may be granulocytes and plasmatocytes, which are known for their role in insect immune defence. [ABSTRACT FROM AUTHOR]

The misuse of antibiotics has led to antibiotic‐resistant "superbugs," prompting the exploration of alternative antibacterial strategies. This study focuses on the promising avenue of photothermal therapy (PTT). Despite numerous advantages, the clinical applicability of PTT as a sole sterilization strategy is hindered by the necessity for higher temperatures, potentially causing harm to healthy tissues. To overcome this challenge, this study introduces antimicrobial peptides (AMPs) to modify the surface of gallium‐based liquid metal (LM) nano‐antimicrobial agents, thereby enhancing their photothermal antibacterial effects within a lower temperature range. First, a novel LM composite nanomaterial, LM@AMP nanoparticles, is synthesized through a sonication process involving 1,2‐distearoyl‐sn‐glycero‐3‐phosphoethanolamine‐N‐[carboxy(polyethylene glycol)], AMP, and LM in an aqueous solution. Herein, AMPs not only contribute to the structural stability of LM nanoparticles but also enhance their selective interaction with bacterial cell membranes. Then, a thorough characterization of LM@AMP nanoparticles is performed, encompassing analyses through electron microscopy, determination of particle size, and assessment of zeta potential. Moreover, the exceptional photothermal properties exhibited by these nanoparticles are validated. Finally, this investigation demonstrates that LM@AMP nanoparticles selectively target bacterial cell membranes, showcasing efficient bactericidal effects (near 100%) at relatively low temperatures under near‐infrared irradiation. [ABSTRACT FROM AUTHOR]

Understanding aerosol‐cloud interactions under pristine atmospheric conditions is crucial for meaningful global climate change predictions. However, ability of aerosol particles to act as cloud condensation nuclei (CCN) activity of aerosols in pristine atmosphere remains limited, mainly because of the difficulty of measuring it in pristine environments. Given the extremely low CCN number concentration under low supersaturations (SSs) and the complex impact of the kinetic limitation in CCN measurements, size‐resolved CCN activity measurements at low SSs cannot be achieved with traditional methods using differential mobility analyzers and a CCN counter (CCNC) because of the low sample efficiency and the impact of particles with multiple charges. To overcome this difficulty, we propose a new method for measuring size‐resolved CCN activity at low aerosol number concentrations. The new method is based on a combined system comprising an aerodynamic aerosol classifier (AAC) and a CCNC (AAC‐CCNC system). A control program was developed to achieve high‐resolution scans of the SS and particle size within a reasonable time frame. A data inversion scheme, including corrections for the transfer function and kinetic limitation, was developed to obtain accurate size‐resolved CCN activity. In July‐August 2022, the new method was used to measure the size‐resolved CCN activity on the Tibetan Plateau. This new method can advance the size‐resolved CCN measurements, thereby enhancing our understanding of aerosol‐cloud interactions in pristine atmosphere. Plain Language Summary: Cloud condensation nuclei (CCN) are the aerosols which can form cloud droplets. Assessing the ability of aerosols to serve as CCN (CCN activity) is fundamental for understanding the interactions between aerosol and clouds and their impacts on climate and precipitation. Particularly in regions with minimal human influence, such as polar areas and the Tibetan Plateau, the low aerosol concentration makes aerosol‐cloud interaction and its climate impact highly sensitive to aerosol CCN activity. However, traditional CCN activity measurement techniques are not applicable at conditions of extremely low aerosol concentrations, restricting the understanding of aerosol‐cloud interactions and their impacts in those regions. In this study, we developed a new system for CCN activity measurements at low aerosol concentration and corresponding data processing algorithm based on a particle size selection technique distinct from that used in traditional systems. The new system was successfully deployed in a field experiment conducted in Qinghai‐Tibet Plateau in summer 2022. Comparison with CCN concentration measurement indicates that the uncertainty of the CCN activity measurement is within a reasonable range. Notably, this marks the first instance of online measurement of particle size‐resolved CCN activity in the hinterland of the Qinghai‐Tibet Plateau. Key Points: A new aerodynamic aerosol classifier‐cloud condensation nuclei counter (AAC‐CCNC) system is developed for measureing size‐resolved cloud condensation nuclei (CCN) activity under low supersaturated conditions in pristine atmospheresUncertainty correction relating to the impact of kinetic limitations in the CCN counter and the transfer function of the AAC is developedThe AAC‐CCNC system is successfully deployed for size‐resolved CCN activity measurements in the Tibetan Plateau [ABSTRACT FROM AUTHOR]

Microphysical observations of precipitating particles are critical data sources for numerical weather prediction models and remote sensing retrieval algorithms. However, obtaining coherent data sets of particle microphysics is challenging as they are often unindexed, distributed across disparate institutions, and have not undergone a uniform quality control process. This work introduces a unified, comprehensive Northern Hemisphere particle microphysical data set from the National Aeronautics and Space Administration precipitation imaging package (PIP), accessible in a standardized data format and stored in a centralized, public repository. Data is collected from 10 measurement sites spanning 34° latitude (37°N–71°N) over 10 years (2014–2023), which comprise a set of 1,070,000 precipitating minutes. The provided data set includes measurements of a suite of microphysical attributes for both rain and snow, including distributions of particle size, vertical velocity, and effective density, along with higher‐order products including an approximation of volume‐weighted equivalent particle densities, liquid equivalent snowfall, and rainfall rate estimates. The data underwent a rigorous standardization and quality assurance process to filter out erroneous observations to produce a self‐describing, scalable, and achievable data set. Case study analyses demonstrate the capabilities of the data set in identifying physical processes like precipitation phase‐changes at high temporal resolution. Bulk precipitation characteristics from a multi‐site intercomparison also highlight distinct microphysical properties unique to each location. This curated PIP data set is a robust database of high‐quality particle microphysical observations for constraining future precipitation retrieval algorithms, and offers new insights toward better understanding regional and seasonal differences in bulk precipitation characteristics. Plain Language Summary: This work introduces a new particle microphysics data set that is useful for improving weather prediction models and in enhancing precipitation estimation techniques. The data set, produced from National Aeronautics and Space Administration's precipitation imaging package, is comprehensive, well documented, and easy to access. It includes observations from 10 locations across the Northern Hemisphere over 10 years, providing information on both rain and snow. This information includes details like particle size, speed, and density, as well as estimates of rainfall and snowfall rates. The data has been standardized and checked for quality, making it reliable and easy to use. This product is a valuable resource for refining methods to measure precipitation, and offers new insights into regional and seasonal precipitation patterns. Key Points: This data set contains high temporal resolution, disdrometer‐derived precipitation microphysics observations from 10 sites over 10 yearsRigorous quality control practices yield a scalable, self‐describing data set packaged into a common, standardized NetCDF formatThe data's diverse geographic and environmental coverage offers new insights into regional and seasonal precipitation processes and patterns [ABSTRACT FROM AUTHOR]

The gain factor of the optical parametric amplification (OPA) process is known to be negligible in the small scale due to low‐interaction‐medium length. Hence, in the nanoscale, OPA is deemed as infeasible. Therefore, in small‐scale‐integrated optical devices, stimulated‐emission‐based amplifiers (lasers) are employed instead of OPAs. In contrast, the major advantage of OPAs over lasers is that unlike lasers which only provide amplification over a narrow spectral band, OPAs provide high‐gain amplification over a very large, user‐controlled spectral band. In this article, it is shown that OPA can yield wideband high‐gain amplification over a nanoscale beam propagation distance through dispersion engineering. This is achieved by a proper tuning of the pump (source) wave frequency, which can maximize the effective medium nonlinearity by a few orders of magnitude, while concurrently maximizing the intracavity energy density, thereby compensating for the small co‐propagation distance for the input (signal) and pump beams. In this study, it is shown that an input wave can be amplified by a factor 108$\left(10\right)^{8}$ in a nanoscale cavity via precise dispersion engineering. Both empirical and computational formulations are used for the investigation, which display a reasonable agreement. [ABSTRACT FROM AUTHOR]

The Assimilative Canadian High Arctic Ionospheric Model (A‐CHAIM) is a near‐real‐time data assimilation model of the high latitude ionosphere, incorporating measurements from many instruments, including slant Total Electron Content measurements from ground‐based Global Navigation Satellite System (GNSS) receivers. These measurements have receiver‐specific Differential Code Biases (DCB) which must be resolved to produce an absolute measurement, which are resolved simultaneously with the ionospheric state using Rao‐Blackwellized particle filtering. These DCBs are compared to published values and to DCBs determined using eight different Global Ionospheric Maps (GIM), which show small but consistent systematic differences. The potential cause of these systematic biases is investigated using multiple experimental A‐CHAIM test runs, including the effect of plasmaspheric electron content. By running tests using the GIM‐derived DCBs, it is shown that using A‐CHAIM DCBs produces the lowest overall error, and that using GIM DCBs causes an overestimation of the topside electron density which can exceed 100% when compared to in situ measurements from DMSP. Plain Language Summary: The Assimilative Canadian High Arctic Ionospheric Model (A‐CHAIM) is a near‐real‐time space weather model of the high latitude ionosphere. A‐CHAIM combines measurements from many different kinds of instruments, including from Global Navigation Satellite System (GNSS) receivers. These GNSS receivers require calibration in order to produce useful data, and a poor calibration can cause A‐CHAIM to produce incorrect results. A‐CHAIM uses a unique technique to calibrate the GNSS receivers self‐consistently without needing outside references. This new technique results in significantly improved performance in the weather model, but produces different calibration results than other GNSS calibration techniques. It is shown that if the other common calibration techniques were used, the weather model would produce large errors when compared to satellite measurements. Key Points: Rao‐Blackwellized particle filtering is used to solve for GNSS Differential Code Biases (DCBs) in a near‐real‐time data assimilation modelThis method produces DCBs with systematic differences when compared to Global Ionospheric Maps, due in part to plasmaspheric effectsDCBs determined using Global Ionospheric Maps can cause significant errors in reconstructed electron density when used in data assimilation [ABSTRACT FROM AUTHOR]

The hour‐to‐hour variability of 388 nm aerosol optical depth (AOD) and single scattering albedo (SSA) derived from near UV observations by the Earth Polychromatic Imaging Camera (EPIC) on the Deep Space Climate Observatory has been evaluated at multiple locations around the world. AOD retrievals by the EPIC near UV algorithm (EPICAERUV) have been compared to ground based AOD measurements at 16 Aerosol Robotic Network (AERONET) stations representative of the most commonly observed aerosol types over geographic regions in three continents. Obtained results show that, in general, the EPICAERUV algorithm reproduces closely the hour‐to‐hour AOD variability reported by AERONET ground‐truth observations. Although most sites in the analysis show high correlation between the AOD hourly measurements by the ground‐based and space‐borne measuring techniques. Best algorithm performance is observed in the presence of carbonaceous and desert dust aerosols. The diurnal cycle of the retrieved SSA product was also analyzed. Although, a direct comparison of hourly EPICAERUV retrievals to equivalent ground‐based observations was not possible, the satellite result shows that diurnal SSA variability as large as 0.05 can be observed mostly associated with carbonaceous aerosols. EPICAERUV observed diurnal cycle of retrieved AOD on a regional basis was examined for the unusually active seasons of aerosol production of Saharan desert dust aerosols in 2020, and during the 2023 Canadian wildfires. Results presented in this study confirm the EPIC near UV aerosol product is well suited for observing diurnal variability of aerosols and, therefore, it is an important resource for climate and air quality studies. Plain Language Summary: Solid and liquid particles suspended in the atmosphere (aerosols) can be measured from space. The Earth Polychromatic Imaging Camera (EPIC) sensor on the Deep Space Climate Observatory satellite, placed about 1 million miles between the Earth and Sun and beyond the Moon (Lagrangian one point), measures the daytime multi‐spectral upwelling radiation emanating from the Earth's sunlit disk on a quasi‐hourly basis. Those measurements combined with accurate radiative transfer modeling and educated assumptions on aerosol particle size distribution and composition allow the determination of the aerosol amount (reported as aerosol optical depth). In this work we evaluate the performance of the EPIC sensor in measuring the diurnal variability of the aerosol load, by direct comparison with ground‐based observations. Reported results show a remarkable level of agreement between two fundamentally different measuring techniques. Applications to observation of the diurnal cycle of aerosols generated by the 2020 flow of desert dust aerosols over the North Atlantic and by the 2023 wildfires season in Canada are also discussed. Key Points: The diurnal variability of aerosol optical depth retrieved from L1 point satellite radiance measurements closely matches surface observationsSeasonal variability of retrieved single scattering albedo is in good qualitative agreement with equivalent ground‐based observationsEarth Polychromatic Imaging Camera aerosol products can be used in the qualitative and quantitative monitoring of extraordinary aerosol events resulting from wildfires and desert dust storms [ABSTRACT FROM AUTHOR]

This study employed density functional theory (DFT) embedded in Wien2K code to evaluate the physical features of the XGeCl3 (X = Rb/Cs) cubic halide perovskites. The structural optimization has been performed considering generalized gradient approximation (GGA) and electronic properties have been computed considering modified Becke‐Johnson potential (mBJ). The formation energy and phonon dispersion analysis establish the stability of the investigated compounds. Mechanical stability is further confirmed by the computed diverse elastic coefficients. It has been discovered that the examined substances are naturally ductile. The refractive index, reflectivity, and absorption coefficient, are among the optical parameters that have been estimated and analyzed. Interesting results have been obtained for the transport properties of XGeCl3 (X = Rb/Cs). The XGeCl3 (X = Rb/Cs) exhibits a high Seebeck coefficient (X = Rb/Cs) and the largest figure of merit (about 0.99), indicating significant potential for thermoelectric applications. [ABSTRACT FROM AUTHOR]

A finite‐difference time‐domain (FDTD) method for modified Lorentz (mLor) media is proposed based on the order reduction of the governing differential equations. The introduced algorithm is verified in the benchmark problem of wave propagation through a thin slab. Several FDTD methods for the modeling of mLor media are also discussed and a numerical dispersion analysis is conducted. Comparisons in terms of accuracy and numerical simulations prove the validity of the schemes for the study of optics and photonic applications. [ABSTRACT FROM AUTHOR]

UV‐C treatment of food products is a non‐thermal, energy‐ and cost‐efficient alternative to traditional thermal treatment. To ensure a shelf‐stable product, it is necessary to understand the UV‐C dose–response relationship of spoilage microorganisms in liquid food. Two product parameters in particular have a significant affect on the UV‐C propagation through liquid food: the absorption of dissolved substances and the absorption and scattering of suspended particles in the liquid. The aim of this study was to investigate the effect of suspended solids on the UV‐C inactivation of Saccharomyces cerevisiae in model suspensions with different opacifiers (silicon dioxide, titanium dioxide, microcrystalline cellulose, calcium carbonate, and polymethyl methacrylate [PMMA]). PMMA spheres with 11 different diameters ranging from 100 to 6 μm were used to determine the influence of particle size on the inactivation process. Particles with a high imaginary part with respect to the refractive index at 254 nm absorb the UV‐C light instead of scattering it. This energy loss results in less inactivation of S. cerevisiae. Non‐absorbing particles affect inactivation if their size results in Mie scattering. Suspensions of particles between 500 nm and 2 μm significantly reduce the efficiency of the process. The greatest influence is seen at a size of about 900 nm, where the Mie scattering efficiency of PMMA in water is at its maximum. Suspensions with turbidity of 1000 NTU, consisting of particles larger than 2 μm, had no effect on the inactivation of S. cerevisiae. Particle sizes that are in the Rayleigh scattering range (<500 nm) show little to no effect on inactivation. This correlation was confirmed by inactivation experiments of S. cerevisiae in cloudy and clarified apple and grape juice. The results show, that the determination of the particle size distribution and its ratio to the wavelength is crucial for predicting the efficiency of microorganism inactivation by UV‐C light. Practical Applications: UV‐C treatment is a cold pasteurization process. It is a cost‐effective alternative to the conventional heat treatment. The inactivation of organisms only occurs when they are directly exposed to the UV‐C light. Liquid foods rather are suspensions than solutions. The presence of suspended particles can significantly reduce the efficacy of the treatment. It is imperative to understand the effect of suspended particles on process efficiency. [ABSTRACT FROM AUTHOR]

Accurate particle size distribution (PSD) measurements of suspended particulate matter (SPM) composed of flocs and aggregates are important to improve understanding of ecological and geomorphological processes, and for environmental engineering applications. PSDs can be measured in situ (in the field) using a submersible sensor, or ex situ (in the laboratory) using samples. The methodological choice is often guided by logistical factors, and the differences in PSDs acquired by in situ and ex situ measurements is of concern. In this study, a laser‐diffraction instrument (the LISST‐200X) was used to compare in situ and ex situ PSD measurements. Samples measured ex situ were stored for three consecutive weeks and measured each week in a laboratory using different stirrer speeds. We observed that ex situ measurements display a higher D50 (median particle size) than in situ measurements of the same sample (up to 613% larger, 112% on average). Our experiments show that the difference between in situ and ex situ measurements can be explained by flocculation of the riverine sediments during the first week of storage. During the subsequent ex situ measurements, the stirring results in a significantly lower D50. Ex situ measurements are therefore unsuitable for flocculated SPM. This study provides recommendations for optimizing PSD measurements by calculating the measurement times required to obtain robust PSD measurements (exceeding 3 min per sample), which are larger for field samples with coarser particles and wider PSDs. Plain Language Summary: Measurements of the size of particles suspended in a water column are important for understanding many processes related to river ecology and morphology. It is possible to measure these particles directly in the field using a submersible sensor (in situ), or by taking samples and transporting them to a laboratory (ex situ). The choice between these options often depends on logistics, with little recognition of the impact that this choice can have on the measurements. In this research, the differences between in situ and ex situ measurements are explored. We find that ex situ measured particle sizes are on average 112% larger than in situ measurements, which can be related to flocculation of the riverine particles. Flocs are a combination of mineral particles (such as silt or clay) and organic particles, forming larger aggregates. Our results show that flocs grow when a sample is taken to the laboratory and stored. During ex situ measurements, which involve stirring, they break apart. Ex situ measurements are therefore unsuitable for determining the natural particle size. We show how long a measurement should last to give a representative particle size. In situ, longer measurement periods are needed. Key Points: The D50, a generic way to parametrize particle size distributions (PSDs), is not an absolute number, but depends on the measurement methodDifferences between in situ and ex situ measured PSDs are caused by the ex situ alteration of flocculated particlesA robust PSD measurement with laser diffraction takes longer for coarser field samples with a wider distribution [ABSTRACT FROM AUTHOR]

This paper presents the feasibility of Fraunhofer diffraction analysis as a measure of the size of fast‐moving inkjet droplets. This measurement method showed that an inkjet droplet measurement tool was possible with a good balance of real‐time measurement and accuracy. [ABSTRACT FROM AUTHOR]

Incorporation of antioxidants, such as phenolic compounds into edible oils has limitations such as rapid release of phenolic compounds, low solubility, low penetration, low accessibility, and rapid degradation by environmental compounds. To solve this problem, the nano‐encapsulation process is offering promising opportunities. In this research, for the first time, the phenolic extract of Mentha aquatica was nano‐encapsulated in nano‐emulsions coated with chitosan, Lepidium perfoliatum gum (LPG), and complex of chitosan and LPG (CCL) (1:1 ratio). Based on various tests (particle size measurement, ζ‐potential, polydispersity index, encapsulation efficiency index, and intensity curve), the LPG coating was the most optimum option for nano‐encapsulation compared to the other coatings. Thus, the LPG‐assisted nano‐encapsulated phenolic extract of M. aquatica was used to improve the oxidative stability of canola oil at three concentrations (100, 200, and 300 ppm). The results of peroxide value and anisidine index tests (as initial and secondary oxidation indicators, respectively) showed that the nano‐encapsulation improved the antioxidant effect of M. aquatica when compared with free extract in canola oil. In a comparative approach, the best sample was obtained from the LPG‐assisted nano‐encapsulated extract (200 ppm) due to the release of more phenolic compounds. The findings from this study showcase how nano‐encapsulation enhances the efficacy of antioxidants in edible oils. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) materials offer great potential in various fields like superconductivity, quantum systems, and topological materials. However, designing them systematically remains challenging due to the limited pool of fewer than 100 experimentally synthesized 2D materials. Recent advancements in deep learning, data mining, and density functional theory (DFT) calculations have paved the way for exploring new 2D material candidates. Herein, a generative material design pipeline known as the material transformer generator (MTG) is proposed. MTG leverages two distinct 2D material composition generators, both trained using self‐learning neural language models rooted in transformers, with and without transfer learning. These models generate numerous potential 2D compositions, which are plugged into established templates for known 2D materials to predict their crystal structures. To ensure stability, DFT computations assess their thermodynamic stability based on energy‐above‐hull and formation energy metrics. MTG has found four new DFT‐validated stable 2D materials: NiCl4, IrSBr, CuBr3, and CoBrCl, all with zero energy‐above‐hull values that indicate thermodynamic stability. Additionally, GaBrO and NbBrCl3 are found with energy‐above‐hull values below 0.05 eV. CuBr3 and GaBrO exhibit dynamic stability, confirmed by phonon dispersion analysis. In summary, the MTG pipeline shows significant potential for discovering new 2D and functional materials. [ABSTRACT FROM AUTHOR]

Background: The analysis of genetically modified organisms (GMOs) in food and feed is broadly based on the detection of target DNA sequences using PCR‐based methods. The first step of a typical workflow in a GMO testing laboratory is DNA extraction and purification. Several DNA extraction methods have been described for this purpose so far. Whatever the method adopted, the yield and the quality of the extracted DNA are essential factors for the success of GMO analysis. Results: The DNA extraction yield was variable between the different methods, while quality and efficiency appeared comparable. Each method allowed a different yield and a slight correlation between inhibition and the food/feed matrix extracted was observed. Particularly for challenging matrices, the method used for DNA extraction has a remarkable influence on both the quality and quantity of the recovered DNA. Small variations in value % GM content were observed in complex, heterogeneous matrices but not in CRMs and homogeneous matrices. Conclusions: In this study, the purpose is not to establish the best method of extraction but to examine several parameters that play an important role in GMO detection and verify a possible effect on the quantified GMO percentage. In particular, it was found that the yield and quality of extracted DNA depends on the type of sample, notably the degree of processing, composition, particle size, and the protocol used, especially in relation to sample intake. The slightly different GM content observed in heterogeneous matrices could raise doubt in the case of samples close to the legal threshold. [ABSTRACT FROM AUTHOR]

Hansen solubility parameters (HSPs), for particles understood as Hansen similarity parameters, can provide valuable information about the surface behavior of nanoparticles. In the past years, several methodologies are developed for scoring and ranking of probe liquids for HSP determination. Two methods available to carry out this determination in a structured way are based on integral extinctions (IE) by Süß et al. and particle size determinations by Anwar et al., respectively. In this study, these two methods of HSP determination are applied on titania, carbon black, and silicon/carbon composites. The differences in scoring and subsequent ranking of a probe liquid list are compared between both methods. Comparable HSPs from both methods are reported as a best‐practice example and additional considerations that need to be considered to properly derive HSPs from the IE‐based method are emphasized. [ABSTRACT FROM AUTHOR]

Backgrounds: The polyelectrolyte complex (PEC) formation using chitosan (Cs) and alginate (Alg) has been employed to carry out Vitamin C (VC) nanoencapsulation because of its instability in adverse conditions. This method includes VC nanoencapsulation using physical cross‐linking. The effect of the mixing order as well as the different mass ratios of both the polymer and the VC content, were investigated on the size, pdi, zeta potential, encapsulation efficiency (EE%), and yield%. Hence, considering different mass ratios of both polymer (4:1–1:4) and VC content (10%–30% w/w of Cs) as independent variables, PECs were formed using 0.1% (w/v) of Cs and Alg solution. Result: The result showed that, for equal mass ratio (1:1) of Cs and Alg, the addition of Alg solution to Cs solution led to lower particle size, while higher particle size was observed with reverse order of addition. However, no significant effect of polymer mass ratios was observed on particle size and NPs stability, while EE varied with VC concentration. Artificial neural network (ANN) was applied to train the experimental parameters Cs: Alg ratios (X1:X2) and VC content (X3) for the output variables. Moreover, process optimization was carried out using multi‐objective genetic algorithm (MOGA) with the goal of lowering particle size and increasing EE while increasing nanoparticle yield. Conclusion: The PEC method effectively encapsulated VC as obtained from higher EE. The Cs: Alg ratio of 4:2.1 and 18% VC content (w/w of Cs) was found optimum for nanoencapsulation. The final ANN‐GA model showed an acceptable agreement with experimental data. [ABSTRACT FROM AUTHOR]

Herein, elastic, optical, and thermoelectric properties of zinc chalcogenides with 2D square lattice and hexagonal phases [s‐ and h‐ZnX (X = GrVI)] are reported. The s‐ZnX and h‐ZnX structures are achieved to be dynamically stable, according to the phonon dispersion studies. All s‐ and h‐ZnX compounds are found to be semiconductor, with direct and indirect bandgaps ranging from 0.81 to 2.77 eV under PBE and 1.70 to 4.15 eV by HSE06 calculations. The effective mass, mobility, and relaxation time of electron and hole carriers in the band structures of s‐ and h‐ZnX are investigated to gain a better insight of these materials. In addition to the phonon dispersion analysis, their mechanical stability in terms of elastic properties is evaluated, and the resulting elastic parameters validate their mechanical stability. The optical properties of s‐ and h‐ZnX are inspected in the occurrence of field polarizations across parallel and perpendicular directions. At room temperature, s‐ZnTe compound has an optimum figure of merit (ZT) value, indicating it as the superlative thermoelectric material in the entire series. These compounds may also be explored in ultraviolet lasers, solar cells, electronic image displays, high‐density optical memory, photodetectors, and solid‐state laser devices. [ABSTRACT FROM AUTHOR]

The study of thermodynamics and kinetics of leaching rare earth elements (REEs) is a fundamental aspect in understanding the mechanism behind the leaching process. Leaching of REEs from coal ash with aqueous solution of organocarboxylic acid is a heterogeneous fluid‐particle system. In the present study, the leaching mechanisms of these three potential organocarboxylic acids, tartaric acid, lactic acid, and citric acid were examined over a range of temperature (30–90°C) at various leaching durations. The kinetic data thus obtained were found to follow deviation from the conventional shrinking core model (SCM). A mixed mechanism model was deduced to be the optimum fit to the data with high precision (R2 > 0.95) and desired graphical linearity with closer interception to the origin. Aluminosilicate matrix remained unaltered after acid treatment which is the unchanged core concluded as from the kinetic mechanism. Morphological analysis using Scanning Electron Microscope (SEM) and particle size determinations were suggestive of significant reduction in grain size post leaching with organocarboxylic acids, tartaric acid being the most effective of all. [ABSTRACT FROM AUTHOR]

This paper studies extremely low frequency (ELF) whistler‐mode waves' behavior within small‐scale magnetic field irregularities in the Earth's magnetosphere, known as magnetic ducts. Based on the magnetic fields' magnitude inside and outside these ducts, they are categorized as high‐magnetic ducts and low‐magnetic ducts (LBD). Using the whistler‐mode dispersion relation analysis, our primary focus is to show that LBDs are prone to leak electromagnetic energy outside the duct. We further investigate the hypothesis that whistlers can propagate within LBDs without any signal loss when the width of the duct corresponds to an integer multiple of the perpendicular wavelengths of the waves inside it. This condition offers a straightforward and effective method for identifying non‐leaking eigenmodes of LBDs. Our analysis of this non‐leaking condition reveals that every LBD possesses a finite number of non‐leaking eigenmodes directly proportional to the duct's width and the magnitude of the ambient magnetic field within it. The analytical results are then validated using two‐dimensional, time‐dependent simulations of the electron‐Magnetohydrodynamics model. Also, we model the non‐leaking propagation of an ELF whistler‐mode wave observed inside the LBD by the NASA Magnetospheric Multiscale mission satellites. Key Points: Magnetospheric Multiscale mission satellites observe whistler‐mode waves inside the low‐magnetic ducts (LBD)We provide an analytical explanation for the occurrence of leaking ducts and show that the LBD are prone to leakSimulations confirm our analytical prediction of the most trapped extremely low frequency wave in the LBD, provided by least degree of leakage [ABSTRACT FROM AUTHOR]

Organs transplanted across donor‐specific HLA antibodies (DSA) are associated with a variety of clinical outcomes, including a high risk of acute kidney graft rejection. Unfortunately, the currently available assays to determine DSA characteristics are insufficient to clearly discriminate between potentially harmless and harmful DSA. To further explore the hazard potential of DSA, their concentration and binding strength to their natural target, using soluble HLA, may be informative. There are currently a number of biophysical technologies available that allow the assessment of antibody binding strength. However, these methods require prior knowledge of antibody concentrations. Our objective within this study was to develop a novel approach that combines the determination of DSA‐affinity as well as DSA‐concentration for patient sample evaluation within one assay. We initially tested the reproducibility of previously reported affinities of human HLA‐specific monoclonal antibodies and assessed the technology‐specific precision of the obtained results on multiple platforms, including surface plasmon resonance (SPR), bio‐layer interferometry (BLI), Luminex (single antigen beads; SAB), and flow‐induced dispersion analysis (FIDA). While the first three (solid‐phase) technologies revealed comparable high binding‐strengths, suggesting measurement of avidity, the latter (in‐solution) approach revealed slightly lower binding‐strengths, presumably indicating measurement of affinity. We believe that our newly developed in‐solution FIDA‐assay is particularly suitable to provide useful clinical information by not just measuring DSA‐affinities in patient serum samples but simultaneously delivering a particular DSA‐concentration. Here, we investigated DSA from 20 pre‐transplant patients, all of whom showed negative CDC‐crossmatch results with donor cells and SAB signals ranging between 571 and 14899 mean fluorescence intensity (MFI). DSA‐concentrations were found in the range between 11.2 and 1223 nM (median 81.1 nM), and their measured affinities fall between 0.055 and 24.7 nM (median 5.34 nM; 449‐fold difference). In 13 of 20 sera (65%), DSA accounted for more than 0.1% of total serum antibodies, and 4/20 sera (20%) revealed a proportion of DSA even higher than 1%. To conclude, this study strengthens the presumption that pre‐transplant patient DSA consists of various concentrations and different net affinities. Validation of these results in a larger patient cohort with clinical outcomes will be essential in a further step to assess the clinical relevance of DSA‐concentration and DSA‐affinity. [ABSTRACT FROM AUTHOR]

Lanthanum germanide (La6Ge) thin films are successfully fabricated using the thermal evaporation technique under a vacuum pressure of 10−5 mbar. The resulting films display an orthorhombic structure, characterized by lattice parameters of a = 8.725 Å, b = 8.063 Å, and c = 5.569 Å. Optical analysis of the La6Ge thin films reveal their high transparency, with an energy bandgap of 3.75±0.04 eV. The bandgap exhibits indirect allowed transitions and featured energy band tails with widths measuring (1.64±0.14) eV. In addition, dielectric dispersion analyses indicate the presence of two dominant dielectric resonance peaks centered at 3.15 and 2.08 eV. Moreover, the La6Ge films demonstrate a terahertz (THz) cutoff frequency of 1.0 THz when illuminated with infrared and visible light. This cutoff frequency increases to 45.6 THz in the ultraviolet range. Furthermore, by utilizing the Drude–Lorentz method, the investigation of optical conductivity parameters reveals that the lanthanum germanide optical filters can achieve free hole density and drift mobility values of 14.44 cm2 V−1 s−1 and 2.8×1018 cm−3, respectively, under infrared light irradiation. The outstanding optical and dielectric properties exhibited by the La6Ge thin films make them excellent candidates for highly transparent optical filters suitable for terahertz technology. [ABSTRACT FROM AUTHOR]

In this study, uneven urban streets are explored with different standard deviations (σH = 0–0.6) through numerical simulations. The ventilation and pollutant diffusion conditions are investigated under the combined action between the thermal buoyancy force and mechanical wind force. When the thermal buoyancy is uniformly distributed, the upstream vortex gradually occupies the most area of the flow unit with the increase in σH. Three configurations of green roof systems (roof, leeward, and windward cooling schemes) are assumed to represent different thermal buoyancy distributions in the street canyon. The average air exchange rate and pollutant retention time (τ) are proposed to evaluate the ventilation efficiency and pollutant dispersion condition. The "free airflow" phenomenon occurs and gradually expands with the increase in the standard deviation of each model. The flow structure and pollutant distribution inside the urban canopy are similar in the uniformly heated and leeward cooling scheme. The windward cooling scheme presents the least local retention time in most working conditions. The roof cooling scheme aggravates the pollutant accumulation conditions inside the street canyon. This study can provide some constructive guidelines in the urban planning process and benefit the design of urban greening with different building morphologies. [ABSTRACT FROM AUTHOR]

The detailed characterization of snow particles is critical for understanding the snow settling behavior and modeling the ground snow accumulation for various applications such as prevention of avalanches and snowmelt‐caused floods, etc. In this study, we present a snow particle analyzer for simultaneous measurements of various properties of fresh falling snow, including their size, shape, type, and density. The analyzer consists of a digital inline holography module for imaging falling snow particles in a sample volume of 88 cm3 and a high‐precision scale to measure the weight of the same particles in a synchronized fashion. The holographic images are processed in real‐time using a machine learning model and post‐processing to determine snow particle size, shape, and type. Such information is used to obtain the estimated volume, which is subsequently correlated with the weight of snow particles to estimate their density. The performance of the analyzer is assessed using monodispersed spherical glass and foam beads, irregular salt crystals, and thin disks with various shapes with known density, which shows <10% density measurement errors. In addition, the analyzer was tested in a number of field deployments under different snow and wind conditions. The system is able to achieve measurements of various snow properties at single particle resolution and statistical robustness. The analyzer was also deployed for 4 hr of operation during a snow event with changing snow and wind conditions, demonstrating its potential for long‐term and real‐time monitoring of the time‐varying snow properties in the field. Plain Language Summary: Our study introduces a snow particle analyzer designed to simultaneously measure various properties of falling snow, including size, shape, type, and density. The analyzer uses a compact digital holography system to capture images of snow particles and a high‐precision scale to weigh them. A machine learning‐based software processes the images in real‐time to extract snow particle properties, which are crucial for estimating the cumulative snow volume and average density. These properties are essential for the investigation of snow morphology, fall speed, accumulation rate, and related study of avalanches and snow drift. The analyzer is accurate, with less than 10% error in density measurement as assessed through laboratory tests. It has been successfully deployed under various snow conditions and provides continuous, real‐time monitoring of changing snow properties, even within the same snowfall event. This information is vital for improving models of snow settling and weather forecast. Compared to existing methods, the snow particle analyzer measures frozen hydrometeors in a larger range of sizes and offers faster, more accurate volume estimation. In addition to snow, the system could be applied to other geophysical processes where the measured particle properties are important, such as monitoring mineral dust, embers, sediments, volcanic ashes, and pollens. Key Points: Snow analyzer measures size, shape, type, and density of falling snow particles using digital inline holography (DIH) and high precision scaleInstrumentation is tested under various snow and wind conditions, providing real‐time snow classification and accurate density measurementsConditions under which single snow particle density can be estimated with sufficient accuracy are discussed [ABSTRACT FROM AUTHOR]

A novel explicit time integration method is formulated with sub‐step strategy and Cubic B‐spline interpolation method. Theoretical and numerical analysis are conducted to obtain optimized algorithm properties including algorithm accuracy, spectral stability and numerical dissipation/dispersion. A demonstrative dispersion analysis for wave propagation is presented to acquire optimal algorithm parameter value for finite element analysis of wave propagation problems. Numerical tests demonstrate that new method show desirable algorithm accuracy and convergence for dynamic problems. Especially, for highly nonlinear problems, the new method can provide very accurate and stable solutions. [ABSTRACT FROM AUTHOR]

Optical and acoustic backscatter measurements are routinely utilized to monitor suspended‐sediment concentration (M); however, both measurements are affected by changes in particle size and density. In this study, optical and acoustic backscatter measurements are combined to a single parameter, the sediment composition index (SCI), to quantify M, mean particle radius by number (ao), the fraction of sediment <20 μm by diameter (f20 $f20$), and particle bulk apparent density (ρbulk). Data are analyzed from Chesapeake Bay and five rivers of Queensland, Australia. SCI is utilized to predict the ratio of M to acoustic backscatter under changes in ao and ρbulk (R2 ranged from 0.6 to 0.98 across all data sets) and combined with acoustic backscatter to predict estimates of M that are independent of changes in ao and ρbulk. SCI is proportional to log10(ao) and f20 $f20$ for SCI from acoustic backscatter measured at 6 MHz (R2 = 0.8 and 0.74, respectively, p‐value < 0.001, n = 133), while SCI(log10(ao)) and SCI(f20 $f20$) from acoustic backscatter measured at 2 MHz or lower are sensitive to changes in floc fractal dimension. Estimates of ρbulk from SCI are biased by changes in particle size (R2 is 0.1–0.5 across all datasets). This study builds upon recent work that derived SCI to quantify composition of sand and mud in suspension and demonstrates the utility of the approach in systems transporting flocculated silt and clay. Future research directions are discussed. Plain Language Summary: Accurate measurement of suspended‐sediment load, the product of discharge and suspended‐sediment concentration, is needed to inform numerous management efforts that aim to either mitigate or enhance the supply of sediment to waterways. Furthermore, given sediment‐related impairments on aquatic ecosystems and the importance of sediment supply to shoreline stability, suspended‐sediment load measurements delineated by particle size across the freshwater to marine domain are of increasing interest. Optical and acoustic backscatter measurements are routinely utilized to monitor suspended‐sediment concentration needed to compute suspended‐sediment load; however, both measurements are affected by changes in particle size and density. In this study we evaluate the use of combining acoustic and optical backscatter measurements to improve the estimation of suspended‐sediment concentration and particle size in suspensions dominated by muddy flocculated sediment. We demonstrate from theory and field observations that combining optical and acoustic backscatter measurements provide estimates of suspended‐sediment concentration that are not biased by changes in particle size and density. Key Points: Optical and acoustic backscatter are combined to estimate the mass concentration, particle size, and density of flocculated silt and clayEstimates of suspended‐sediment concentration and particle size are unbiased by changes in particle size and densityImplications for suspended‐sediment load monitoring and research are discussed [ABSTRACT FROM AUTHOR]

A novel amphiphilic photoreactive block copolymer was synthesized by electrochemically mediated atom transfer radical polymerization (eATRP) of glycidyl methacrylate (GMA), N-vinyl carbazole (VK) with polyethylene glycol-based initiator (PEG-Br). And then the double bond and the boric acid group were introduced through the epoxy group. Fluorescent molecularly imprinted nanoparticles (nano-FMIPs) were prepared using self-assembly imprinting technology with PEG-b-P(GMA-co-VK) as a functional monomer and sialic acid (SA) as a template molecule. The nano-FMIPs prepared by this method have the advantages of uniform size and small particle size, which greatly improves their recognition performance. It is found that the SA template can significantly quench the fluorescence intensity of nano-FMIPs linearly within a concentration range of 4 x 10-4-4 x 10-6 mol L-1, which is well described by Stern-Volmer equation. The nano-FMIPs can selectively and sensitively detect down to 2.9 µM of SA concentration. This study provides a new and general strategy for the preparation of nano-MIPs with high selective recognition ability in aqueous media, which has good application prospects in biomedicine. [ABSTRACT FROM AUTHOR]

Aim: The geography and genesis of diversity remain an enduring topic in ecology and evolution. Mediterranean Climate Ecosystems (MCEs), with their high plant diversities in winter rainfall climates, pose a challenge to popular hypotheses evoking high water availability and temperature as necessary for the evolution of high diversity. We test the hypothesis of environmental stability as a driver for the evolution of regional‐scale floristic diversity using speleothem oxygen (δ18O) and carbon (δ13C) isotopic values as proxies for past climatic variability in the Cape Floristic Region (CFR) and other MCEs. Location: south‐western Africa, California, Mediterranean Basin. Taxon: Plantae. Methods: We present new speleothem δ18O and δ13C records from a cave near Robertson in the western CFR. Stable isotope samples included in the analyses cover the time intervals between 240 and 670 ka BP with hiatuses at 630–500 ka and 360–310 ka. The dispersion of these stable isotope records is used as a measure for climatic variability. We compare our new analyses to speleothem records that cover full glacial and interglacial conditions in other MCEs (California and the Mediterranean Basin) as well as in eastern regions of the CFR. All sites used in this comparison have lower vascular plant biodiversity than the western CFR. Results: Analyses of the dispersion of the δ18O and δ13C datasets suggest that the highly diverse western CFR experienced climatic stability across several glacial–interglacial cycles, compared with the less diverse regions within and outside of the CFR. Main Conclusion: This result provides support for the hypothesis that lower extinction rates associated with Pleistocene biome stability may explain the higher diversity in the CFR relative to other MCEs. [ABSTRACT FROM AUTHOR]

We analyze seismic records collected at the oldest (170–180 Ma) Pacific seafloor using broadband dispersion array analysis. Using ambient noise and teleseismic waveforms, we measure Rayleigh‐wave phase velocities in a period range of 5–200 s that are inverted for array‐average one‐dimensional isotropic and azimuthally anisotropic shear‐wave velocity depth profiles from the crust to a depth of 300 km. The high‐velocity Lid and the low‐velocity zone are well‐resolved with velocity difference of ∼4%, whose transition occurs at depths between 80 and 100 km. The profile is compared with that obtained at the 130‐ and 140‐Ma seafloor. Accounting for the cooling effect due to the plate age difference, the low‐velocity zone of the oldest Pacific seafloor is ∼1.3% slower (∼110°C warmer) than that beneath the 140‐Ma seafloor, suggesting the occurrence of some reheating process beneath the oldest lithosphere. The azimuthal anisotropy at shallow depths (<50 km) is significantly different between the western and eastern areas of the array where the peak‐to‐peak amplitudes are estimated to be ∼2.8% and ∼1.6%, respectively. The fast direction is nearly parallel to the past seafloor spreading direction (perpendicular to the magnetic lineation) in the west, while it largely deviates in the east. The observed difference in azimuthal anisotropy may represent complicated evolution dynamics of the infant Pacific plate that involved a ridge‐ridge‐ridge triple junction. Plain Language Summary: One of the classical enigmas of plate tectonics is the cause of seafloor flattening where the seafloor depth becomes nearly constant for old ages (>∼70 Ma) while a simple cooling model of plate evolution predicts the age dependence. To solve this enigma, it is essential to resolve the subsurface structure of the oceanic plate and the asthenosphere below. As a part of an international effort, Pacific Array, that aims to cover the Pacific seafloor by arrays of ocean bottom seismometers, a team of Japanese and Korean scientists deployed an array in the oldest (170–180 Ma) Pacific seafloor. We determine isotropic and anisotropic shear‐wave velocity structures as a first step toward resolving the enigma. The results indicate that the asthenosphere beneath the oldest Pacific lithosphere is significantly slower than the prediction of the simple cooling and that the occurrence of some reheating process may be needed. Furthermore, azimuthal anisotropy (the dependence of the wave velocity on the horizontal propagation direction) in the shallow lithosphere shows that the anisotropy patterns differ between the eastern and western areas of the array, and simulation results indicate that the evolution process of the infant Pacific plate is not merely a simple triangular plate spreading. Key Points: Broadband Rayleigh‐wave dispersion array analysis has been conducted in the oldest (∼170 Ma) Pacific seafloorThe low‐velocity zone is significantly slower to indicate the occurrence of some reheating process beneath the oldest Pacific lithosphereThe spatial variation of the shallow azimuthal anisotropy indicates a complicated evolution of the infant Pacific plate [ABSTRACT FROM AUTHOR]

The size distribution of dust emitted from soils determines particle attributes such as the enrichment in elements that are important for biogeochemical cycles, global climate and human health. There is an ongoing discussion about the size distribution of dust and its relationship with saltation and wind speed. In this work, we present our own results and discuss them in the context of other studies, emphasizing on dust emission from agricultural soils, which is relatively complex and less studied. The objective of this work was to evaluate the particle size distribution of the emitted dust or particulate matter (PM) up to 32 μm in diameter (PM32) from an agricultural sandy soil under two saltation‐supply conditions, using a wind tunnel coupled to a dust‐suspension chamber. We found strong correlations between friction velocity, saltation flux and dust emission. Additional saltation supply increased the total dust PM32 emission at high wind speeds up to three‐fold. Correlation between wind speed and dust concentration was best explained by a power law, with exponents up to 12.04 for the 20 to 32 μm particle‐size range under high‐saltation conditions, but much lower (up to 4.34) for the 0.25 to 1 μm size range under low saltation. An increase of the wind speed affected significantly the concentration of the coarser dust fraction (PM > 10 μm), but affected less the concentration of fine dust (PM from 10 to 1 μm) and did not affect the concentration of the ultrafine (PM < 1 μm) fraction in the suspension chamber. Results found suggest that dust is mostly produced from particles less than 60 μm in diameter, both by fragmentation and direct wind lift. Results found herein reinforce one of the existent theories, but raise questions about the influence of the soil type, and the place and timing of the sampling arrangements. [ABSTRACT FROM AUTHOR]

We investigate numerically the effect of hydrodynamic dispersion on convective dissolution of carbon dioxide in saline aquifers. Solutions of the transport equations were used to describe the dissolution process in the aquifer and provide a systematic parametric analysis of the influence of dispersion on two important measures of convective dissolution, the wavenumber, and dissolution flux. The results suggest that dispersion decreases the dissolution rate and reduces the finger wavenumber. Based on the simulated results, new empirical scaling laws that predict the dissolution rate and wavenumber were developed. The application of the new laws to two storage sites shows that the currently available predictions overestimate the dissolution rates by ∼30%. We have identified some discrepancies between published scaling laws that were obtained for the dissolution rate. While most numerical studies identify a linear scaling, experimental investigations often suggest a sublinear behavior. Our findings resolve the controversy by suggesting that dispersion, which was not considered in these past numerical studies, is the reason for the apparent sublinear scaling. Key Points: We investigate the effect of hydrodynamic dispersion on convective CO2 dissolution by numerical simulations and develop new scaling lawsWe show that hydrodynamic dispersion decreases the finger wavenumber and the CO2 dissolution fluxApplying the scaling laws suggests a significantly smaller dissolution flux in actual storage sites than estimated before [ABSTRACT FROM AUTHOR]

The Southern Ocean (SO) is a unique region with rich ecosystems and minimal anthropogenic and terrestrial natural impacts especially during austral summer. We conducted measurements and sampling of aerosol particles to investigate the characteristics and role of aerosol particles in cloud formation on Japanese research vessel Mirai over the SO in the late austral summer of 2017. Observations of air masses with minimal terrestrial impacts indicated that bimodal aerosol particle size distributions were mostly observed over the SO and relative abundances of two modes varied with the changes in the structure of the marine boundary layer (MBL) such as surface mixing layer. As the local minimum diameter between two modes (DH) is considered a critical size for cloud‐droplet activation in the MBL, we analyzed the aerosol particles with diameter larger than DH (CNAcc) as a proxy for cloud condensation nuclei. Variations in the concentrations of aerosol particles with diameter larger than 300 nm were accounted for by the sea‐spray source function, whereas it substantially underestimated those of CNAcc. This implies the significance of the nonsea‐spray sources of CNAcc in the MBL over the SO. The concentrations of ice nucleating particles (NINPs) active at −25°C were 20–100 m−3, consistent with recent observations over the summertime SO. The observational evidence of very low NINPs relative to the CNAcc concentrations (40–110 cm−3) over a wide area of the SO is important for predicting the effects of cloud radiative properties on the radiative balances over the SO using climate models. Plain Language Summary: Aerosol particles in the marine boundary layer (MBL) can substantially affect cloud formation over the ocean, indicating their significance for the Earth's radiative budget. The Southern Ocean (SO) is a unique region with rich ecosystems and minimal anthropogenic and terrestrial natural impacts especially during austral summer. On Japanese research vessel Mirai, we conducted shipborne measurements of the aerosol particle size distributions and sampling of aerosol particles to investigate the characteristics and role of aerosol particles as nuclei in cloud formation over the SO in the late austral summer of 2017. Our observations indicate that the major contributor to the number of aerosol particles active as cloud condensation nuclei (CCN) was likely nonsea‐spray processes, and ice nucleating particles (INPs) concentrations were 20–100 m−3 at −25°C during the research cruise. These findings are consistent with those of recent studies over the summertime SO. The observational evidence of very low concentration levels of INPs relative to the CCN concentrations over a wide area of the SO is important for accurately predicting the cloud phases (liquid, ice, or mixed) and their effects of cloud radiative properties on the radiative balances over the SO by climate models. Key Points: Summertime aerosol particles as nuclei for cloud formation over the Southern Ocean were investigatedAerosol concentrations were strongly controlled by sea‐spray emission, secondary formation, and the marine boundary layer structureConsistent with recent observations, ice nucleating particle concentrations were extremely low compared to accumulation mode particles [ABSTRACT FROM AUTHOR]

Using the fraction velocity dispersion analysis method, it has been shown recently that in two impulsive solar energetic electron (SEE) events, the release times of near‐relativistic electrons at the Sun for outward‐propagating electrons are energy dependent and are delayed compared to those of the downward‐propagating electrons. In this work, we perform a statistical study of the release time and its energy dependence of near‐relativistic electrons in impulsive SEE events. We use in situ observations from the WIND spacecraft and remote hard X‐ray observations from the RHESSI and/or Fermi spacecraft. The difference in the release times between outward electrons and downward electrons for 29 events is obtained. In all events, the release of the outward‐propagating electrons is delayed from those precipitating downward. In 26 of the 29 events, the release times of outward‐propagating electrons also show clear energy dependence. In 15 of these 26 events, in situ electron data from more than five energy channels were available. The delay time as a function of energy for nine of these can be fitted by a form proposed by G. Li et al. (2021, https://doi.org/10.1029/2021GL095138). The implication of this energy‐dependent release on the Magnetohydrodynamics turbulence property at the electron acceleration site is discussed. Key Points: Delay of the release of in situ electrons from hard X‐ray generating electrons in impulsive solar energetic particle events is examined for 29 eventsClear delays are seen in all events and in most events the delay is energy dependentThe delay shows no energy dependence in fewer than 20% events and the traditional velocity dispersion analysis method only applies in these events [ABSTRACT FROM AUTHOR]

The effects of microtopography on erosion remain uncertain, and contradictory findings have been reported in past decades, hindering full understanding and accurate prediction of the quantity and quality of soil erosion caused by rainfall‐runoff. In this study, we applied a dynamic wave and Hairsine‐Rose model simulator on hillslopes composed of various sizes of mounds and puddles. For the tested soil particles whose settling velocity is 0.0035−300mm/s $0.0035-300\,\mathrm{m}\mathrm{m}/\mathrm{s}$ and rainfall intensity of 100mm/hr $100\,\mathrm{m}\mathrm{m}/\mathrm{h}\mathrm{r}$, we found that soil erosion quantity is significantly affected by microtopographic roughness, even under the same rainfall‐runoff conditions. In addition, we found that soil particle size can potentially determine whether there is a direct or inverse proportionality relationship between microtopographic roughness and soil erosion rate on hillslopes. That is, when the land surface layer is composed of relatively small soil particles, rough microtopographies accelerate soil erosion rates compared to smooth microtopographies. In contrast, when it is composed of large soil particles, soil erosion increases more on smooth microtopographies than on rough microtopographies, at least under the tested conditions. Finally, it was revealed that the progress of the microtopographic scale armoring process is closely related to the microtopographic roughness as well as the grain size. Thus, to appropriately consider the role of microtopography in soil erosion problems, the processes of pickup, advection, and deposition related to armoring must be physically considered. Without sufficient information on these features, low prediction accuracy is expected, not only of the quantity but also in the quality of soil erosion. Key Points: Microtopography can change the quantity and quality of watershed erosion even under the same hydrological conditionsWhether soil erosion rate is directly or inversely proportional to microtopographic roughness is determined by soil particle sizeMicrotopographic scale armoring processes play an important role in size‐selective soil erosion on a hillslope [ABSTRACT FROM AUTHOR]

Improvement of transmission efficiency of spin waves in magnonic devices is crucial for high‐efficiency magnon‐based operations. However, existing techniques for enhancing spin‐wave detection signals, which either improve waveguide material quality or convert other forms of external energy into magnon energy, are still not efficient and convenient enough. Here, it is experimentally demonstrated that low‐k spin waves (where k is the wavenumber) transmission efficiency can be enhanced through yttrium iron garnet (YIG) surface metallization owing to the significantly increased group velocity and low spin‐pumping efficiency at low k. Given that the shielding effect of the conductive metal on YIG increases the spin‐wave group velocity from 55 to 132 km s−1, the weak magnon‐dissipation mechanism of low‐k spin waves provides the foundation for signal enhancement. Through a detailed theoretical analysis on dispersion relations and spin‐wave amplitude, the detected signal strength is increased to 2 times for copper and 2.24 times for gold is verified. In detail the competition between the spin‐pumping effect is discussed and the enhanced group velocity is introduced by the metal decoration. This competition describes the essence of partial signal enhancement in the spin‐wave transmission spectrum. The work provides a practical way to achieve spin‐wave manipulation and low‐loss transmission. [ABSTRACT FROM AUTHOR]

This study investigates (ZnO)s with different surface features as vulcanization activators in unfilled SBR vulcanizates. ZnO is termed the best activator due to its fast reaction kinetics. A high release of ZnO into the environment harms marine ecosystems, and most ZnO production goes to the rubber sector; therefore, reducing ZnO amount is essential. Active, nano and functionalized ZnO compared to conventional ZnO in SBR matrix; concentration optimized based on curing, mechanical, physical, and dispersion analyses. The Arrhenius equation approximated the cure curve's kinetic constant and activation energy. Crosslink density measured by swelling experiment and solvent freezing point depression. Nano ZnO was used from 0.5 to 2phr, active ZnO from 1 to 4phr, and functionalized ZnO from 1 to 3phr compared to 5phr of conventional ZnO. The tensile strength of N1.5, F1.5, and A2 SBR increased by 5%, 26%, and 18% compared to C5SBR, whose elongation at break improved by 30%, 7%, and 23%. The data were analyzed using tukey HSD post hoc test. Regarding mechanical properties and curing characteristics, 2phr active, functionalized, and 1.5phr nano ZnO is analogous to 5phr conventional ZnO in an unfilled SBR matrix. The quantity of ZnO in rubber vulcanizates decreased successively by 60%, 60%, and 70%. [ABSTRACT FROM AUTHOR]

This research examined the occipitoparietal deformations of the Early Bronze Age skulls from the southern European part of Russia and the similarities between those deformations and head modifications among the population of the Okunev culture in Southern Siberia. The study objects used were 3D models of neurocrania from 41 individuals retrieved from Early Bronze Age graves in the northwestern Caspian Sea region and 64 individuals from the Okunev graves. Analyses, of the skull shape variations, included geometric morphometrics, generalized Procrustes analysis, and principal component analysis with visualization of morphological changes as heat maps. Statistically significant differences between the subgroups were tested by performing dispersion analysis (ANOVA) using the Geomorph package. The samples of Early Bronze Age skulls from the southern European part of Russia showed differences between deformed and non‐deformed skulls, as well as differences in the location of the deformed regions in both males and females. The differences between chronological groups turned out to be stronger than the difference between undeformed and deformed skulls in the Okunev samples. The next analysis focused only on the Okunev deformed skulls involving a study and assessment of the differences in the types of deformation between the early and late subgroups. The final analysis demonstrated similarities between the Bronze Age male deformed neurocrania from the northwestern Caspian Sea region and those from the early Okunev culture. The study confirmed the occipitoparietal flattening on the Bronze Age skulls from the southern European part of Russia using geometric morphometrics. This skull deformation finds analogies among deformed male neurocrania from the early chronological horizons of the Okunev culture. The similarity of head modifications in populations from different geographical regions indicates contact between these populations. This is confirmed by archaeological data and nonmetric cranial traits. [ABSTRACT FROM AUTHOR]

Dispersion of liquid in bubble column is an important process in chemical and allied industries. In the present work, the dispersion characteristics of liquid phase in a bubble column is studied in three different surfactant solutions. A comparative analysis on the dispersion characteristics of liquid phase in different surfactants has been carried out. The gas holdup and mixing time are also analysed. The effect of different physiochemical properties and operating variables on the dispersion coefficient and gas holdup is examined. A novel model for the estimation of dispersion due to bubble motion has been developed which incorporates the effect of gas holdup, liquid viscosity and circulation velocity. The contribution of dispersion coefficient due to the bubble motion in overall dispersion is also examined. The value of velocity distribution parameter in three different surfactant solutions is also compared. Generalised correlations for gas holdup, dispersion coefficient and mixing time are also developed based on the physicochemical properties of liquid. This research may be useful for the selection and application of these three surfactants in industries. This article will also help researchers for designing multiphase flow system where role of dispersion due to the motion of bubbles is significant. [ABSTRACT FROM AUTHOR]

The present study emphasizes a multi‐scale analysis of an environmental dispersionin a fully developed shallow wetland flow under the wind effect, based on the momentum and mass transfer equations. From the classical momentum equation, the depth‐dominated velocity profile is derived for the wetland flow. The environmental dispersion is examined using Mei's multi‐scale analysis on moment equations of concentration in wetlands with wind‐induced effect. Further, the maximum velocity, thickness of separation layer with recirculation and its position are obtained. The increase of depth‐averaged velocity was observed for the larger contribution of conveyance capacity in wetland flows for the enhancement of wind direction. Also, the analytical result showed that the higher magnitude of environmental dispersion led to intensive dispersion process for the depth‐dominated wetland flow. Moreover, for the hierarchical composition of contaminant constituents, the duration and length of influenced region are associated with a certain standard water quality level in wetland. [ABSTRACT FROM AUTHOR]

Carbon nanotubes functionalized with long‐chain compounds were obtained. Using different characterization techniques, such as thermogravimetric analysis (TGA), infrared spectroscopy (FTIR), x‐ray photoelectron spectroscopy (XPS), Raman spectroscopy, surface area analysis and electron microscopy (EM), it was possible to characterize the carbon nanotubes, verifying the presence of the added aliphatic chains, as well as the formation of the amide bonds, the morphological and structural changes of the material. Those functionalized with oleylamine showed dispersion stability in Colombian commercial diesel for at least 70 days, by visual inspection; using UV‐Vis absorbance and particle size measurement it was determined that in the first hours after the generation of the dispersion there was sedimentation of a portion of the material to reach an equilibrium point in which 75 % of the particles continued in suspension. [ABSTRACT FROM AUTHOR]

Surface wave dispersion data is used to infer the shear wave velocity structure variation in the north‐east Himalaya and Indo‐Burmese arc regions. We have used 25 earthquakes data from four groups with a magnitude range of 5.0–6.7, epicentral distance range 368–800 km, and focal depth less than 50 km. Ray paths from the earthquake location to the seismic station are transversely passing different geotectonic units of the Himalayas, Indo‐Gangetic plains, and Indo‐Burma collision zones. The weighted average dispersion curve and the path averaged shear wave velocity models are computed for the four groups located at different azimuths around Shillong seismic station. Non‐linear least‐square inversion is performed to obtain the shear wave velocity structure of the crust and uppermost mantle from joint inversion of Rayleigh and Love waves group velocities. Subsequently, Rayleigh and Love waves group velocities are inverted separately to obtain vertical and horizontal components of S‐wave velocity. Next, using these components anisotropy coefficient values at different depths for each path are also estimated. A high variation of dispersion curves and the shear wave velocity models from one group to another indicates that the region is geotectonically very complex. An approximately 80 km‐thick zone beneath the study region has shear wave velocity as low as 1.7 km/s in the uppermost crust in the southern part and ~4.7 km in the uppermost mantle beneath the Eastern Himalayan Syntaxis (EHS). Inferred velocity is also lower than that of PREM and AK135 global models with a much thicker crust beneath the study region. Radial anisotropy varies even within the northern part from the Indo‐Eurasian collision zone to EHS and northern to southern Indo‐Burma ranges. Anisotropy is comparatively stronger in the deeper part below ~40 km for the three paths, except for the EHS, where the result is contrary. [ABSTRACT FROM AUTHOR]

We present Rb and Sr mass fraction and 87Sr/86Sr isotope ratio measurement results for four reference materials (RMs) obtained from the Service d'Analyse des Roches et des Minéraux (SARM), Nancy, France: Mica‐Mg, Mica‐Fe, GL‐O and FK‐N. These four RMs have different chemical compositions spanning the range of those of most K‐bearing feldspars and micas, making them potential calibration materials for in situ Rb‐Sr dating of natural minerals by LA‐ICP‐MS/MS. Selected grains and flakes from the four RMs present variable degrees of heterogeneity observable by SEM‐EDS and EPMA imaging, and chemical mapping. This heterogeneity is mainly related to inclusions of minerals within flakes and grains and to chemical substitutions linked to crystallographic control and alteration processes. The Mica‐Mg RM is the least affected. The powders available at the SARM were analysed by ID‐TIMS (87Sr/86Sr and Sr) and ID‐MC‐ICP‐MS (Rb) after digestion and separation. The mean 87Rb/86Sr ratios are 155.6 ± 4.7% (2s, as for other RMs) for Mica‐Mg, 1815 ± 14% for Mica‐Fe, 36.2 ± 11% for GL‐O and 69.9 ± 5.9% for FK‐N. The mean 87Sr/86Sr ratios are 1.8622 ± 0.36% (2s, as for other RMs) for Mica‐Mg, 7.99 ± 13% for Mica‐Fe, 0.75305 ± 0.12% for GL‐O, and 1.2114 ± 0.17% for FK‐N. The four RMs each show dispersion in 87Sr/86Sr and Rb and Sr mass fractions, to degrees that differ between RMs and that reflect the heterogeneity of their original crystals. The most heterogeneous RMs are GL‐O and Mica‐Fe. The calculated mean Rb‐Sr isotopic ages are 521 ± 24 Ma for Mica‐Mg, 287 ± 55 Ma for Mica‐Fe, 89.2 ± 9.9 Ma for GL‐O and 512 ± 30 Ma for FK‐N. The proposed age for Mica‐Fe may be unreliable due to the elevated dispersion of individual analysis linked to the highly radiogenic composition of the biotite and to the presence of numerous mineral inclusions. We recommend use of these proposed working values of 87Sr/86Sr and 87Rb/86Sr ratios and associated uncertainties when using the four RMs for in situ Rb‐Sr dating by LA‐ICP‐MS/MS. The availability of these four well‐characterised RMs will allow progress in the development and application of the Rb‐Sr dating approach by LA‐ICP‐MS/MS. [ABSTRACT FROM AUTHOR]

Aim: Incompatibility of intravenous drugs is dangerous and therefore undesirable. The aim of this study was to identify the most commonly acquired intravenous drugs in five neonatal intensive care units and test these for compatibility. Methods: The most frequently acquired drugs in five key hospitals in the South‐Eastern district of Norway for 2019 and 2020 served as a proxy for the prevalence of use. Representatives were selected from the three most prevalent groups based on the Anatomical Therapeutic Chemical classification system. Co‐administration of drug pairs was simulated using clinically relevant concentrations and infusion rates representing mixing ratios in the catheter. Particle formation was assessed by particle counting and size measurement, by visual examination using Tyndall beam, by turbidity and by measuring pH of mixed samples. Results: The most frequently acquired drug groups were anti‐infectives, neurological agents and cardiovascular drugs. Compatibility testing revealed that both ampicillin and benzylpenicillin were incompatible with morphine. Flecainide and fluconazole showed no signs of incompatibility with morphine. No information on these combinations in a neonatal‐relevant setting is available. Conclusion: We recommend to abstain from co‐administering ampicillin and benzylpenicillin with morphine in neonatal intensive settings. Morphine co‐administered with flecainide and fluconazole in neonatal patients were evaluated as safe. [ABSTRACT FROM AUTHOR]

The production of coalbed methane gas depends upon various factors such as permeability, gas content, gas saturation and seam thickness. The low permeability in coal is a constraint in the gas extraction process. However, the presence of natural fractures and cleats in coal increases the permeability; therefore, its identification is necessary to establish the prospectivity. Hence, a methodology is used to process the Stoneley waveform in the Bokaro coalfield located in India to obtain slowness magnitude from the semblance analysis. The separation of directly transmitted and reflected Stoneley waves determines the reflection coefficient and attenuation, and its analysis emphasizes the presence of fractures. In coal seams, the average reflection coefficient ranges from 0.42 to 2.44 and attenuation ranges from 0.2 dB to 12.68 dB. The Stoneley slowness versus frequency plot shows a constant slowness with increasing frequency in the non‐fractured seams, whereas a dispersive trend is observed in the fractured seams. Fractures are also distinguished from the cross‐plot of compressional/shear versus Stoneley velocity. The observation of higher reflection coefficient, attenuation and slowness‐frequency dispersion in coal seams indicates extensive fractures/cleats that corroborate with the resistivity image log correlation. Thus, the study helps to distinguish between fractured and non‐fractured coal seams from the integrated approach of reflection coefficient, attenuation and dispersion analysis of Stoneley waves supported by the identification of fractures from resistivity image log for optimization in coalbed methane production in the development phase. [ABSTRACT FROM AUTHOR]

A new type of flexible explosive(HFE) with high energy and low vulnerability based on H‐RDX(High‐quality RDX) was proposed. Fundamental characterizations of H‐RDX, including infrared testing and particle size measurement, were carried out. The technological parameters of the process were researched. Mechanical sensitivities were characterized by impact sensitivity tester and friction sensitivity tester on the base of the explosion probability method. Energetic properties containing densities, initiation properties, and detonation velocities were investigated. For comparison, normal RDX was introduced. It is concluded that HFE with great flexibility was obtained under the sulfuration condition of 80 °C, 10d. The surface of H‐RDX is smoother with fewer defects and a smaller specific surface, leading to the better safety performance of HFE. The impact and friction sensitivities of HFE were 50 % and 22 % less than those of RDX‐based flexible explosive, respectively. Moreover, higher densities and a 6∼19 % rise in detonation velocities indicate that HFE(6700∼7500 m ⋅ s−1) has better energy performance. The precise incision was realized as the dosage of HFE rose(thickness, from 3 mm to 5 mm). The waterproofness of HFE was also tested by the detonation of the sample(submerged in 1 m water for 24 h) with the optimum proportion of the formula(explosive/rubber/functional agents=92/6/2). An excellent application prospect of the flexible explosive was observed in this work. [ABSTRACT FROM AUTHOR]

Implicit staggered‐grid finite‐difference methods are attractive for elastic wave modelling due to significantly enhanced spatial accuracy compared to explicit ones. However, the central‐grid finite‐difference operators used to approximate the temporal derivatives result in a limited accuracy in time. Temporal high‐order finite‐difference methods have the ability to weaken the temporal dispersion and improve the modelling stability. It is noted that the previous temporal high‐order and spatial implicit finite‐difference methods are all designed in the space domain for performing acoustic wave propagation. To implement 2‐D elastic wave simulation with high‐order accuracy both in space and time, we propose two time–space domain implicit staggered‐grid finite‐difference schemes, in which the spatial derivatives are approximated by the weighted average of a few extra off‐axial nodes and axial nodes of the conventional cross‐stencil. We derive the P‐ and S‐wave dispersion relations of the whole elastic wave equation and estimate the finite‐difference coefficients via a variable substitution‐based Taylor‐series expansion. Our Taylor‐series expansion‐based new scheme yields high‐order temporal and spatial accuracy. Besides, the spatial accuracy can be further enhanced by our newly proposed linear optimization strategy, which benefits from easy implementation since we only optimize the axial spatial coefficients via a least‐squares strategy and set the off‐axial temporal coefficients the same as the solution of the Taylor‐series expansion method. Besides, the P‐ and S‐wave separation approach is adopted to propagate the P‐ and S‐wavefields with the P‐ and S‐wave dispersion relation‐based finite‐difference operators, respectively. Our two new schemes are more capable of suppressing the numerical dispersion and exhibit better stability performance compared to conventional one, as we will illustrate via a detailed analysis of dispersion, stability and numerical experiments. In addition, a comparison of computation times demonstrates the efficiency advantage of two new schemes since small operator lengths and large time steps are allowed. [ABSTRACT FROM AUTHOR]

We show that an ion‐ion cross‐field streaming instability between cold newborn cometary ions and heated heavy ions that were picked up upstream is likely a contributing source of observed lower hybrid (LH) waves in the inner coma of comet 67P/Churyumov‐Gerasimenko. Electric field oscillations in the LH frequency range are common here, and have previously been attributed mainly to the lower‐hybrid drift instability, driven by gradients associated with observed local density fluctuations. However, the observed wave activity is not confined to such gradients, nor is it always strongest there. Thus, other instabilities are likely needed as well to explain the observed wave activity. Several previous works have shown the existence of multiple populations of cometary ions in the inner coma of 67P, distinguished by differences in mass, energy and/or flow direction. We here examine two selected time intervals in October and November 2015, with substantial wave activity in the LH frequency range, where we identify two distinct cometary ion populations: a bulk population of locally produced, predominantly radially outflowing ions, and a more tenuous population picked up further upstream and accelerated back toward the comet by the solar wind electric field. These two populations exhibit strong relative drifts (∼20 km/s, or about five times the pickup ion thermal velocity), and we perform an electrostatic dispersion analysis showing that conditions should be favorable for LH wave generation through the ion‐ion cross‐field instability. Key Points: Pick‐up ions and locally produced cometary ions co‐occur in the inner coma, with strong relative streaming motionAn ion‐ion cross‐field instability can develop as a result of the relative streaming motionThis instability can be responsible for generating at least some of the lower hybrid waves observed at the comet [ABSTRACT FROM AUTHOR]