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Methodologies across the dispersion preparation, characterization, and cellular dosimetry of hydrophilic nanoparticles (NPs) have been developed and used extensively in the field of nanotoxicology. However, hydrophobic NPs pose a challenge for dispersion in aqueous culture media using conventional methods that include sonication followed by mixing in the culture medium of interest and cellular dosimetry. In this study, a robust methodology for the preparation of stable dispersions of hydrophobic NPs for cellular studies is developed by introducing continuous energy over time via stirring in the culture medium followed by dispersion characterization and cellular dosimetry. The stirring energy and the presence of proteins in the culture medium result in the formation of a protein corona around the NPs, stabilizing their dispersion, which can be used for in vitro cellular studies. The identification of the optimal stirring time is crucial for achieving dispersion and stability. This is assessed through a comprehensive stability testing protocol employing dynamic light scattering to evaluate the particle size distribution stability and polydispersity. Additionally, the effective density of the NPs is obtained for the stable NP dispersions using the volumetric centrifugation method, while cellular dosimetry calculations are done using available cellular computational modeling, mirroring approaches used for hydrophilic NPs. The robustness of the proposed dispersion approach is showcased using a highly hydrophobic NP model (black carbon NPs) and two culture media, RPMI medium and SABM, that are widely used in cellular studies. The proposed approach for the dispersion of hydrophobic NPs results in stable dispersions in both culture media used here. The NP effective density of 1.03–1.07 g/cm3 measured here for black carbon NPs is close to the culture media density, resulting in slow deposition on the cells over time. So, the present methodology for dispersion and dosimetry of hydrophobic NPs is essential for the design of dose–response studies and overcoming the challenges imposed by slow particle deposition. [ABSTRACT FROM AUTHOR]

Ceratium furcoides is a dinoflagellate that exhibits invasive behavior in the aquatic ecosystems of South America and has been expanding its range in recent years. In this study, we monitored 151 municipalities in southern Brazil between 2012 and 2019 with the objective of detecting and recording the species' occurrence and abundance in the state of Rio Grande do Sul, as well as to examine its expansion and persistence pattern. Ceratium furcoides was recorded in 84.1% of the monitored municipalities, in all three of the state's hydrographic regions (HR). Spatially, the Guaiba HR showed the highest density for the species (10,912 cells mL−1); in temporal scales, 2014 and 2015 displayed density peaks, usually in the summer. The cumulative area invaded by C. furcoides gradually increased, reaching 266,625 km2 in 2018, corresponding to about 94% of the state; however, the highest expansion rate (3142 km year−1) and longest distance covered (40.4 km) occurred in 2012, during its introduction. The expansion varied over the studied years, initially heading toward HR Littoral and Guaiba (between 2012 and 2014), followed by a steady period (2015–2017), and subsequently a progression toward HR Uruguay (2018). The frequency analysis showed that persistence was short in most of the municipalities. The results indicate that local environmental characteristics, especially temperature and precipitation, could be key for the invasion and development of the species. Given its rapid expansion, statewide dispersibility, and extremely large bloom formation, Rio Grande do Sul looks to be C. furcoides' second home. [ABSTRACT FROM AUTHOR]

Aim: Distribution of species is one of the most elementary but fundamental biodiversity patterns, yet too many puzzles remain unsolved. In most cases, distribution of species is not random, but presents some degree of aggregation. Accordingly, the term 'distributional aggregation' is prevailingly used in ecology and evolutionary biology to reflect the non‐random distribution characteristic of species in space and time. However, its meanings are multiform and can be decomposed into a variety of components. Location: Global. Methods: In this paper, through synthesizing historical literature and comparing relevant meanings of distributional aggregation under different contexts, we summarize the current statistical metrics in detecting and evaluating distributional aggregation that are suitable for different field‐survey methods, study models and sampling scales. In particular, we explore the concept under the multi‐species setting for which few conceptual advances and statistical methods have been developed. Results: We propose pure data dispersion and spatiotemporal proximity, as two basic components of distributional aggregation. We further explore three advanced components of distributional aggregation: orthogonal, hierarchical and parallel components that can simultaneously link sampling taxa, sampling sites and sampling methods. Main Conclusions: We hope the systematic review can serve as a potentially useful primer to ecologists for better understanding and investigating complex and new distributional patterns of biological diversity. We further provide informative guides on developing new statistical methods and metrics. We also discuss useful simulation algorithms for generating diverse distributional aggregation patterns of species, aiming to help ecologists to test and compare the performance of different metrics related to diversity and distribution patterns of species. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed masses. The developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a matrix. The inclusions are idealized by lumped masses, and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed masses. Additionally, the model is capable of depicting the wave propagation in bi-material bars, wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed masses. The discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered, and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method (LPM). Next, a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization technique. The subsequent use of the second-order method of multiple scales (MMS) facilitates the derivation of the corresponding nonlinear dispersion relation in a closed form. The novelties of the present study consist of (i) considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains; (ii) developing the second-order LPM for the wave propagation in the discrete chains; and (iii) deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed masses. Finally, a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum models. These parameters include the ratio of the spring mass to the lumped mass, the nonlinear stiffness coefficient of the spring, and the wave amplitude. [ABSTRACT FROM AUTHOR]

This paper examines the short-term or transient dynamics of SIR infectious disease models in patch environments. We employ reactivity of an equilibrium and amplification rates, concepts from ecology, to analyze how dispersals/travels between patches, spatial heterogeneity, and other disease-related parameters impact short-term dynamics. Our findings reveal that in certain scenarios, due to the impact of spatial heterogeneity and the dispersals, the short-term disease dynamics over a patch environment may disagree with the long-term disease dynamics that is typically reflected by the basic reproduction number. Such an inconsistence can mislead the public, public healthy agencies and governments when making public health policy and decisions, and hence, these findings are of practical importance. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates factors influencing the stability of reserve currencies. Analysis of Ukraine's economic indicators reveals a strong relationship between GDP, CPI, exports, imports, and exchange rates. Despite 2022 being a turbulent year for the euro, the US dollar remains the primary global reserve currency. Factors contributing to the dollar's dominance include its stable value, the size of the US economy, and geopolitical power. Effective management of the interaction between the dollar and euro is crucial for global economic stability and growth. Both currencies can coexist and thrive, with the euro potentially contributing to a more balanced global monetary system. Correlation-regression analysis of their competition reveals significant relationships, underscoring their impact on global economic processes. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are of interest in various industries owing to their high aspect ratio, electrical conductivity, and other properties. By maximizing the number of CNTs in their solvents or matrices, the electrical and mechanical performance in applications such as batteries, sensors, and transistors can be enhanced. However, the hydrophobicity of CNTs' surface induces aggregation that adversely impacts their performance. To overcome this obstacle, many researchers have been designing novel dispersants with performances exceeding that of existing commercial dispersants. This article reviews contemporary studies on CNT dispersants from 2015 to 2022, along with the comprehensive features of CNTs depending on their chirality, number of walls, synthesis methods, and functionalization. Studies of CNT dispersants are primarily organized according to whether aqueous or organic solvents are used. This review article provides a clear perspective of CNT dispersants development today and how to design new CNT dispersants depending on the solvents. A conclusion is given to identify major challenges to the implementation of CNT dispersion and an outlook on future avenues of research. [ABSTRACT FROM AUTHOR]

This study investigated the effect of copper (Cu) doping content on zinc oxide with varied weight percentages and the dispersion of Cu-doped ZnO (CZO) by adding polyvinylpyrrolidone (PVP), coated on a glass substrate, through a physical assessment and optical property and thermal insulation testing. CZO NPs were synthesized by using the sol–gel method with a zinc acetate precursor. The powder X-ray diffraction (XRD) patterns of the CZO showed that the solid solubility limit was below 5 mol% without a secondary phase. A field-emission scanning electron microscopy (FE-SEM) micrograph demonstrated that the particle size of CZO was in nanoscale with the packing of a quasi-spherical shape. The UV-Vis-NIR reflectance spectra of the powder showed that 1 mol% CZO has the highest near-infrared (NIR) reflectivity in the wavelength 780–2500 nm, with great visible light transmission. The CZO NPs were loaded in acrylic copolymer in different weight percentages ranging from 25 wt% to 75 wt%, the film thickness of the coating was varied from 5 µm to 100 µm, and PVP was added into this nanocomposite polymer to disperse through an ultrasonication method. The results showed that the highest loading of CZO powder in a polymer at 75 wt% in 100 µm of thickness with polyvinylpyrrolidone (PVP) as a dispersant showed better sample dispersion and retained good transparency to the naked eye. [ABSTRACT FROM AUTHOR]

The dynamics of swarm robotic systems are complex and often nonlinear. One key issue is to design the controllers of a large number of simple, low-cost robots so that emergence can be observed. This paper presents a sensor and computation-friendly controller for swarm robotic systems inspired by the mechanisms observed in algae. The aim is to achieve uniform dispersion of robots by mimicking the circular movement observed in marine algae systems. The proposed controller utilizes binary sensory information (i.e., see or not see) to guide the robots' motion. By moving circularly and switching the radii based on the perception of other robots in their line of sight, the robots imitate the repulsion behavior observed in algae. The controller relies solely on binary-state sensory input, eliminating the need for additional memory or communication. Up to 1024 simulated robots are used to validate the effectiveness of the dispersion controller, while experiments with 30 physical robots demonstrate the feasibility of the proposed approach. [ABSTRACT FROM AUTHOR]

The potential of geometrically induced terahertz surface wave technology for communications can only be realized if communication links based on them are studied and benchmarked. The frequency‐dependent transmission characteristics of interconnects based on three different archetypal textured surfaces (namely, gratings, dominos, nails) are analyzed numerically and the impact of the geometry and realistic surface roughness on the maximum capacity and energy efficiency is quantified. Unlike conventional hollow waveguides, the analysis shows that the capacity of uncoated corrugated surfaces is limited by loss and not dispersion. This work provides the guidelines for the design of terahertz surface wave interconnects. [ABSTRACT FROM AUTHOR]

Ascertainment of photonic stopband absolute topological character requires information regarding the Bloch eigenfunction spatial distribution. Consequently, the experimental investigations predominantly restrict themselves to the bulk‐boundary correspondence principle and the ensuing emergence of topological surface state. Although capable of establishing the equivalence/inequivalence of bandgaps, the determination of their absolute topological identity remains out of its purview. The alternate method of reflection phase‐based identification also provides only contentious improvements owing to the measurement complexities pertaining to the interferometric setups. To circumvent these limitations, the Kramers–Kronig amplitude‐phase causality considerations are resorted to and an experimentally conducive method is proposed for bandgap topological character determination directly from the parametric reflectance measurements. Particularly, it is demonstrated that in case of 1D photonic crystals, polarization‐resolved dispersion measurements suffice in qualitatively determining bandgaps' absolute topological identities. By invoking the translational invariance of the investigated samples, a parameter "differential effective mass" is also defined, that encapsulates bandgaps' topological identities and engenders an experimentally discernible bandgap classifier. [ABSTRACT FROM AUTHOR]

Copyright of Revista Gestão & Tecnologia is the property of Revista Gestao & Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The invasion of false carmine cochineal Dactylopius opuntiae (Cockerell) (Hemiptera; Dactylopiidae) in the Mediterranean region presents a serious threat to cactus pear cultivation. The cochineal was first identified in Israel in 2013, and it soon became clear that biological control is the only long-term solution to protect the cactus pear Opuntia ficus-indica. Releases of the introduced predatory beetle Hyperaspis trifurcata Schaeffer (Coleoptera; Coccinellidae) began in 2016, demonstrating high efficacy and leading to a decline in cochineal populations and plant survival. While H. trifurcata can autonomously reach new cochineal hotspots, it often arrives too late to prevent substantial damage to cactus pear. Human intervention is therefore necessary to expedite the predator’s establishment in new infested sites. To facilitate the spread of the beetle, we consider two approaches: transferring beetle seeding stocks from northern locations through a volunteer network organized by the research team, and applying the ’predator – prey dual introduction’ concept to preemptively mitigate new hotspots expected to emerge as the cochineal spreads southward via winds or birds. These activities have led to a major decrease in the rate of spread of the cochineal population in the East Mediterranean, and in the damage that it inflicts to cactus pear hedgerows. Implementing a similar approach in North Africa can prevent or slow the spread of the cochineal to the northern coast of the central Mediterranean and avoid the heavy damage experienced in Morocco.

ABSTRACT Marine pest introductions continue to occur and increase at accelerated rates, threatening the marine environment and blue economy. Environmental DNA (eDNA) is a tool for determining the presence of both indigenous and nonindigenous species, via the detection of genetic material that is shed into the local environment. Although eDNA approaches have gained widespread adoption in the last decade, fundamental knowledge gaps remain around factors that can influence the probability of detection, and how to optimize eDNA sampling in aquatic environments. Here, we partition eDNA research into four major research themes: eDNA concentration (shedding and decay), transport (advection and mixing), sampling design strategies, and the modeling of these dynamics. We review current developments and challenges in each theme with a focus on field sampling strategies and the use of biophysical models for understanding the movement of modeling eDNA in complex aquatic environments. We then introduce three modeling case studies from a large embayment where we (1) quantify the spatial and temporal variability of eDNA dispersion, (2) use biophysical models to inform a field sampling strategy, and (3) demonstrate a backtracking modeling technique to identify upstream DNA sources to an existing sample (monitoring) site. We conclude by identifying specific recommendations to help improve future eDNA studies. This work highlights how biophysical models can be applied to improve early detection and informing response and management decisions.

Abstract Widely used methods to assess population genetic structure and differentiation rely on independence of marker loci. Following the assumption, the common metrics, for example FST, evaluate genetic structure by averaging across loci. Common metrics do not use information in the associations among loci at the individual level and are often criticized for failing to measure true differentiation even when loci segregate independently. We introduce a new concept to measure β‐variation (Effective Number of Different Populations, ENDP). It requires the following steps: (a) calculation of a proper dissimilarity between genetic profiles of all individuals; (b) calculation of suitable pairwise distances between the samples based on the dissimilarities between individuals; (c) calculation of diversity (in terms of Hill numbers) and dispersion of samples based on the pairwise distances between samples; (d) ENDP is then estimated by combining the diversity and dispersion. ENDP estimates β‐variation independently of estimates of within‐sample α‐variation, although β‐ and α‐estimates could statistically correlate to some extent. This new concept differs from the existing standard where β‐diversity is estimated based on the “partition of variation” scheme (beta=gamma−alpha or beta=gamma/alpha), so that estimates of β‐diversity directly depend on the corresponding values of α‐diversity. ENDP estimates are obtained by evaluating information in the available genetic profiles of individuals including association of loci. Therefore, ENDP can be used even in an absence of panmixia. We illustrate the use of this concept by analyzing the population genetic structure of a sexual species (a trematode parasite) occupying connected populations across a broad geographic area. The analysis is complicated by geographically coexisting cryptic species and the potential mixed‐mating system of this hermaphroditic parasite. Analyses with subsampled data demonstrated that ENDP estimates are robust. Number of loci used for genotyping has much stronger effect on variation of point ENDP estimates than sample size.

This work reports the observation of sunlight diffraction through empty spaces in between twigs and leaves in tree crowns. The diffraction patterns are dominated by red wavelength on front followed by the trail of rest of spectral bands of white light rainbow bursts. Tree crowns act as obstacles and apertures causing diffraction/ interference of solar rays. Separation between leaves and twigs (d) is a few inches and distance between crown and camera (D) is in range of a few meters. Empty spaces in tree crown are much longer than red to violet wavelengths in sunlight therefore scattering, dispersion, reflection, diffraction and interference effects cannot be ruled out. Tree crown deflects solar rays into narrow angles all around to enable interference inside camera lens to create grating structure diffracting light into regular patterns. Diffraction pattern look like red petunia flower having 3 × 3 rose petals. Motorola mobile phone camera was used to record the sunlight diffraction patterns. Mobile camera consists of small focal length (≈5 mm) lens, a fixed opening aperture and an image sensor. Lens consists of few plastic or glass elements and sensor consists of charge coupled device (CCD) or CMOS technology. These diffraction/ interference patterns have potential to increase efficiency of Next Gen solar cells. This paper describes possible theoretical background of light diffraction and multiple ray interference through tree twigs and leaves.

Air-conditioning systems are on track to demand most of the electricity consumed by buildings around the world. The authors propose that dispersing quantum dots into the chilled water loops of air-conditioners represents a path towards improving the efficiency of air-conditioners. As such, the thermophysical properties of carbon-based quantum dot ‘nanofluids’ (e.g., nanoparticles dispersed in liquids) are presented in this study for sub-ambient temperatures (5–15°C)—an under-explored temperature range which requires understanding for air-conditioning applications. This study also explores dispersion stability and materials compatibility—another under-explored area in the literature which is required for commercial uptake. In this study, carbon quantum dots were synthesized via the hydrothermal route and characterized with UV–Vis, FT-IR, Raman spectroscopy, and TEM. Next, the thermophysical properties of specific heat capacity, thermal conductivity, and viscosity of the nanofluids were experimentally measured between 5 and 15°C (not previously reported for aqueous quantum dots). The highest thermal conductivity enhancement was ∼11% (compared to DI water) for 0.3 wt.% at ∼11 °C. Finally, the stability of the fluid was monitored over time and after exposing the fluids to common materials used in air-conditioning systems (e.g., copper, brass, and stainless steel). Unchanged UV–Vis spectra and the lack of sedimentation indicate that the developed dispersions are indeed suitable for chilled water air-conditioning applications.

El presente artículo tiene como propósito explorar las formas de interpretación de la enfermedad entre los rarámuri. Mediante entrevistas y observación en distintos periodos de trabajo de campo intentamos dar cuenta de que, a padecimientos como la tuberculosis, la diabetes o la hipertensión, se suman sintomatologías corpóreas y anímicas –entre otras, las producidas por el susto– que, para los rarámuri, son una enfermedad del alma, que afecta gravemente al cuerpo, perturbando su estabilidad y equilibrio físico. Intentamos mostrar que para los rarámuri los efectos de la covid-19 tuvieron menor impacto, debido a la dispersión de los asentamientos y, al mismo tiempo, encontramos que para los rarámuri las diversas interpretaciones de la enfermedad y sus efectos estuvieron ligados a su propia imagen del mundo, debido a que aún emplean métodos tradicionales de prevención y de curación de las enfermedades.

The sea cucumber Isostichopus badionotus has been overfished along its Mexican distribution, but no abundance recovery has been observed despite management efforts. Restocking and sea ranching strategies can use releasing individuals, and magnitude of protected areas be related on species dispersion knowledge. We measured the short-term movement paths on I. badionotus and their relation with environmental variables. In addition, the influence of biofilm presence/absence on artificial shelters surfaces and the use for animals were compared. Data was obtained through time-lapse cameras in experiments performed in outer aquaria under the natural fluctuation of temperature and sunlight. We observed that larger (Le) individuals exhibited greater daily movement distances (D) (D=0.89*Le −2.533 cm); furthermore, the sea cucumbers move faster in bare aquaria than aquaria with sand. The mean daily movement without sand was 518 cm for small sizes, 615 cm for medium, and 688 cm for large sizes. In the presence of sand, was 127, 196, and 315 cm, respectively. Movement was minimal in the morning/early afternoon (07:00–15:00), a maximum in the afternoon/evening (15:00–23:00), and an intermediate at night/early morning (23:00–07:00). The movement of the small sea cucumbers (>5.96−10.75 cm), was linked to light. Medium-sized and large sea cucumbers (>10.6−19.69 cm) respond to changes in temperature. We observed a higher rate of shelter use by small sea cucumbers (53 % of the day) and a greater affinity for pre-conditioned shelters (80 % of shelter use). Medium-sized and large animals did not show any shelter preferences. Results indicate low dispersion of I. badionotus on daily timescale. The affinity found in small animals towards shelters with biofilm, and their use only in this size class, makes them essential for survival in restoration strategies.

ABSTRACT: Heat stress in broilers is a pressing issue in the changing climate. Data on broiler behavior might be useful for early detection of heat stress and subsequent intervention, and may provide potential indicators for heat tolerance that can be used in broiler breeding programs. Here, we used bird location data collected in a previous study during which broilers were inadvertently exposed to high ambient temperatures due to a local heat wave. We examined whether broiler behavior changed with increasing ambient temperatures, focusing on group-level dispersion behavior and individual-level locomotor activity. We observed that birds moved closer together with increasing temperatures up to 9 °C above the desired level, and remained in similar proximity or moved further apart at temperatures above that threshold. The activity level decreased or remained stable with increasing temperature during most parts of the day, but increased at the end of the day. Possibly, the birds exhibited compensatory behavior (such as drinking and eating) during the periods when the barn cooled down after a hot day, but that could not be confirmed as no behavioral observations were available. The difference in activity levels between individuals accounted for 8.4% of the total variation, suggesting that activity might be an interesting indicator trait for heat tolerance in broiler chickens. Overall, the results of this study can inform the development of behavior-based 1) early-warning systems for heat stress and 2) heat tolerance indicators, although data on behaviors that are more specific to heat stress are probably required.

The signal distribution of any fiber-optic network system is an important factor in optical communication, which determines the quality of the optical signal transmission. One of the important effects is the temperature degrees; that effect is on the main parameters of optical communication (of which the fiber optic is the main part). The main material in fiber optics is glass. And as is well known, temperature has a strong effect on the glass, especially the core of fiber optics, because the structure of fiber optics contains several glass layers with different refractive indexes. Hence, in the present article, the effect of temperature on the optical signal and other components of the optical network system has been analyzed and studied. The analysis includes aberration, dispersion, and distortion of the optical network communication signal. The result has been discussed and analyzed for variables in the BW of the spectral when the temperature changed.

All optical soliton communication is a new generation of ultra-long distance and ultra-high speed optical fiber communication technology. Optical cavity solitons (CSs), whose pulse property is unique, have shown great potentials in optical soliton communication systems. Here, a theoretical model of nonlinear fiber resonator for CS generation is proposed. The effect of pump laser and resonant cavity parameters on the CS pulse performance is detailedly investigated and deeply analysed. Furthermore, the synergistic effect of continuous wave (CW) pump laser power and pump pulse peak power, and the synergistic effect of dispersion condition, fiber nonlinear coefficient and fiber length on the generation and property of CS pulse are respectively discussed and summarized. Finally, the launch conditions and parameter variation tolerances of cavity soliton in nonlinear fiber resonant cavity have been successfully generalized. These results can provide important instruction to the experimental generation and optimization of CS pulse.

The extensive utilization of marine concrete results in a significant consumption of cement, thereby leading to an increase in CO2 emanations. Enhancing the potency and longevity of marine concrete serves as an efficacious approach to mitigate CO2 emanations. The objective of this investigation was to introduce colloidal silica nanoparticles with distinct three-dimensional structures (MCM-41, SBA-15, and DFNS) for the purpose of enhancing the mechanical functionality and longevity of remarkable sulfate persistence Portland cement. Meantime, the incorporation of silica nanoparticles with distinct three-dimensional architectures (DFNS, MCM-41, and SBA-15) into marine cement mortar was carried out, and an investigation was conducted on the aggregation of silica nanoparticles, as well as the humidifying process and micro-process of the mortar. According to the findings, the addition of silica NPs improved the resilience, mechanical traits, and longevity of the marine cement cases. When the inclusion of silica nanoparticles with varying three-dimensional structures (DFNS, MCM-41, and SBA-15) was implemented, a decrease in both the chloride diffusion coefficient and porosity was observed. The compressive intensity of cement mortar was enhanced in the presence of DFNS, MCM-41, and SBA-15 when compared to control samples, following a rehabilitating period of 5, 15, and 30 days. These advancements in intensity and longevity suggest that DFNS exhibits considerable potential in mitigating CO2 emanations within the marine concrete industry.

OBJECTIVE: Persons with schizophrenia exhibit greater neurocognitive test score dispersion. Here, we seek to characterize dispersion on the Neurocognitive Composite subtests of the Measurement of Treatment Research to Improve Cognition in Schizophrena Consensus Cognitive Battery (MCCB) and determine the relative effects of different antipsychotic formulations on dispersion and mean performance. METHOD: In this post hoc analysis of the DREaM study (NCT02431702), which compared treatment with paliperidone palmitate (PP) long-acting injectable with oral antipsychotic (OAP) treatment over 18 months, dispersion in MCCB neurocognitive subtest performance was calculated for each participant by visit (test occasion). RESULTS: Over 18 months, mean neurocognitive performance improved in a manner consistent with the expected effects of practice in both groups (p

The article analyzes different approaches to estimating risk of declining efficiency of investment projects that are recommended to practical use by academic literature. The author pointed to their subjectivity and high uncertainty of results. As an alternative we can consider approaches and methods of estimating risk of declining efficiency of the investment project as a difference between the expected by the project and risky values of its NPV defined by the law of this figure distribution. In this case the risky NPV assessment depending on the ratio to risk is either its average value in the field of existence limited from above by expected in the project value or any quantile located in the field of possible NPV values. The article presents substantiation of the standard law of NPV distribution as a complicated random value formed by a sum of random variables, i.e. features of finances flows by the project and discount. The author also analyses the approach to estimating dispersion of the NPV distribution law and risky values depending on its amount based on this figure expansion into the Tailor series with initial data showing average values and dispersion of its finance flows and discount.

The aim of the work is to analyze the physical and mechanical properties of grain of spring barley varieties cultivated in the conditions of the Predkamsk zone of the Republic of Tatarstan. The research was conducted in Tatarsky Research Institute of Agriculture FRC of Kazan Research Center RAS in 2015–2022. In the conditions of the Predkamsk zone, on average over the years of research, the late maturing variety Endan was characterized by reliably high values of 1000 grain weight (48.5 g), the early maturing variety Kamashevsky – reliably high values of natural grain weight (686, 3 g/l), convergence from 2.8 x 20 mm sieve (33.9 %) and coarseness (70.02 %), medium maturing variety Raushan – higher variability in 1000 grain weight (18.6 %), convergence from 2.8 and 2.5 x 20 mm sieves (55.6 and 29.7 %, respectively) and coarseness (39.5 %). The direct dependence of the mass of 1000 grains, runoff from the sieve 2.8 x 20 mm and coarseness on the sum of precipitation (r = 0.41/0.58/0.56, respectively), GTC (r = 0.40/0.58/0.55, respectively) and inverse dependence of these physical and mechanical properties on the average daily air temperature (r = -0.51/-0.62/-0.63, respectively) of the interphase period "earing-full ripeness" were established at 1% significance level. Judging by the value of the coefficient of determination (r2), the most closely related to the average daily air temperature are the signs "mass of 1000 grains", "drift from the sieve 2.8 x 20 mm" and "coarseness". The analysis of path coefficients revealed a high direct positive contribution (0.87) of 2.8 x 20 mm sieve runoff and an average direct positive contribution (0.43) of 2.5 x 20 mm sieve runoff to grain yield. Under the conditions of the Predkamsk zone, the prevailing contribution to the total variance of the traits "drift from the sieve 2.8 x 20 mm", "coarseness", "weight of 1000 grains", "bulk grain weight", "drift from the sieve 2.5 x 20 mm" was made by the factor "year", which accounted for (in descending order) 81.7...80.3...76.6...76.2. 68.7 %, respectively.

The dispersion of the refractive index of (La0.06Ga0.94)2O3:Eu thin films obtained by radio-frequency ion-plasma sputtering has been studied. It was found that the films have a polycrystalline structure corresponding to the monoclinic structure of β- Ga2O3. It is shown that the freshly deposited films are characterised by an abnormal dispersion, and after annealing in argon, a normal dispersion of the refractive index is observed. It was found that at normal dispersion, the spectral dependence of the refractive index in the visible region of the spectrum is mainly determined by electronic transitions from the 2p-state oxygen band, which form the upper filled level of the valence band to the bottom of the conduction band formed by hybridised 2p-states of oxygen and 4s-states of gallium. Two single-oscillator approximation models were analysed and compared for the films annealed in argon, and the approximation parameters, dispersion energy, degree of chemical bond ionicity, coordination number, and static refractive index were determined.

Abstract In recent years, the power conversion efficiency (PCE (%)) of perovskite solar cells (PSCs) has improved to over 26%. To enhance the photovoltaic properties of PSCs, several materials for the electron transport layer (ETL) have been investigated. Zinc oxide (ZnO) is a significant ETL due to its high electron mobility and optical transparency in PSCs. As a result of various deposition methods, ZnO ETL can be processed at low temperatures. On the other hand, based on several studies, metal-doped ZnO can facilitate electron transfer, thereby improving the performance of un-doped ZnO ETL-based PSCs. Here, to improve the PCE (%) and long-term stability of un-doped ZnO ETL-PSCs, silver (Ag)-doped ZnO 1wt% as a buffer layer is examined. In this paper, with the addition of an organic solvent (ethanol) to the dispersion of Ag-doped ZnO 1 wt% nanoparticles (NPs) in deionized (DI) water, the morphology of the buffer layer (Ag-doped ZnO 1 wt%) can be controlled. This approach focuses on reducing the wettability of the ZnO/Ag-doped ZnO 1 wt% bilayer ETLs and enhancing the stability of un-doped ZnO ETL-PSCs. According to the results, the ZnO/H2O-ethanol mixtures-Ag-doped ZnO 1 wt% bilayer ETL leads to the formation of high-quality perovskite with low defects, reducing the recombination rate, and long-term stability of un-doped ZnO ETL-PSCs in ambient conditions.

The beneficial effect of carbon nanotubes (CNTs) to enhance the electrical conductivity and piezoresistivity of cement-based materials was highly contingent upon its dispersion. To achieve an appropriate dispersion of CNTs, ultrasonication, high-speed stirring, and chemical dispersion were commonly used, which raises the risk of structural damage of CNTs caused by the excessive energy. In this study, electrostatic self-assembly of Fe3O4 nanoparticles on CNTs was employed to efficiently disperse CNTs. To optimize the dispersion effect of conductive fillers in cement paste, the mix proportions including sodium dodecyl sulfate (SDS) concentration, CNTs concentration, and Fe3O4/CNTs ratios were adjusted. The dispersion degree and electrical property were evaluated by UV–vis absorption and zeta potential. In addition, the effect of self-assembled conductive filler dosage on the electrically conductive property of cement pastes was examined. The results show that the occurrence of electrostatic self-assembly was proved by the change of zeta potential, and the grape-bunch structure was observed by transmission electron microscopy. Further, the optimal proportions of self-assembled conductive fillers were 0.20 wt% SDS concentration, 0.05 wt% CNTs concentration, and 1:1 Fe3O4/CNTs ratio. The self-assembled conductive filler dosage between 0.02 and 0.10 wt% can effectively improve the electrical conductivity of cement paste with up to 68% reduction of resistivity.

Reservoir computing (RC) is a bio-inspired framework suited for temporal data processing. Here we propose an all optical coherent RC for the equalization of the impairments of fiber optic (FO) system based on coherent detection. We compare the performances of the RC systems based on semiconductor saturable absorber mirror (SESAM) and highly nonlinear waveguide (HNLW). For a dispersion managed long haul FO system in which the nonlinear penalty is dominant, we find that the SESAM outperforms the HNLW due to its larger nonlinear memory. In contrast, for the equalization of dispersive impairments in a short haul FO system such as data center networks, we find that the HNLW has a much superior performance due to its larger linear memory.

In this paper we present a dual band low cross-polarized periodic microstrip leaky wave antenna (LWA) based on the multi mode resonator concept (MMR). The structure is capable of frequency dependent backward dual-beam steering and fast forward beam scanning in the upper and lower operating band, respectively. A gap loaded microstrip line is used as a host transmission line to feed the combination of the periodic patch radiators on the top and the bottom etched slots leading to the generation of the forward and the backward space harmonics. The etched ring slots at the bottom surface of the structure are not only responsible for steering the beam in the backward direction in the bottom hemisphere in its upper band but also adds radiation diversity in the overall radiation mechanism in its two operating bands. The potential use of this antenna resides in its ability to produce in-plane fast forward beam steering suitable for autonomous vehicle navigation systems in its lower band and out-of-plane backward-symmetric dual beam steering in the upper operating bands, suitable for tracking in relay systems.

We study the implementation of a numerical method to solve the time fractional (2+1)-dimensional Wu–Zhang system focusing on properties of trigonometric basis functions (TBFs). The approximation of the system describing dispersive long waves by appropriate discretization of the system and Grünwald difference operators is discussed and a linear system of the resulting discrete systems is given. This process includes a presentation of a general framework to approximate the solution by a mesh-free scheme which is stable and converges. Finally, various numerical experiments are present to illustrate the exceptional effect of fractional-order on the WZ system.

The article identifies invasive fish species in freshwater ecosystems in India and investigates their detrimental effects on the sustainability of endemic fish species. The study discusses the role on invasive fish species in the predation of native species, change of food web and species abundance and diversity, disruption of ecosystem functions and services, biodiversity loss, economic loss, health hazards and range extension. It calls for measures to protect freshwater fish biodiversity.

The dispersion of structural waves, where wave speed varies with frequency, introduces significant challenges in accurately localizing occupants in a building based on vibrations caused by their movements. This study presents a novel multi-sensor vibro-localization technique that accounts for dispersion effects, enhancing the accuracy and robustness of occupant localization. The proposed method utilizes a model-based approach to parameterize key propagation phenomena, including wave dispersion and attenuation, which are fitted to observed waveforms. The localization is achieved by maximizing the joint likelihood of the occupant’s location based on sensor measurements. The effectiveness of the proposed technique is validated using two experimental datasets: one from a controlled environment involving an aluminum plate and the other from a building-scale experiment conducted at Goodwin Hall, Virginia Tech. Results for the proposed algorithm demonstrates a significant improvement in localization accuracy compared to benchmark algorithms. Specifically, in the aluminum plate experiments, the proposed technique reduced the average localization precision from 7.77 cm to 1.97 cm, representing a ∼74% improvement. Similarly, in the Goodwin Hall experiments, the average localization error decreased from 0.67 m to 0.3 m, with a ∼55% enhancement in accuracy. These findings indicate that the proposed approach outperforms existing methods in accurately determining occupant locations, even in the presence of dispersive wave propagation.

The dispersion of titanium dioxide (TiO2) determines the performance of TiO2-based formulations in cosmetic and coating applications. In particular, the chemical and structural characteristics of the surfactants used to prepare TiO2 dispersions are significant. However, the influence of surfactants on TiO2 dispersion quality has not been systematically investigated. In this study, we observed the effects of the ionic character of commercial surfactants on the dispersion stability and UV-blocking efficacy of TiO2. Among the experimental surfactant groups, anionic sodium dodecyl sulfate was efficient in stabilizing TiO2 as a water-in-oil formulation and enhancing its UV-blocking efficacy. Furthermore, an anionic fatty acid as a surfactant with a longer alkyl chain length was sufficient to stabilize the TiO2 formulation, which also displayed the highest UV-blocking efficacy, comparable to the values of commercial TiO2-based cosmetic products.

Multistatic imaging systems are commonly used in radar systems and microwave imaging. In these systems, many antennas are arranged three-dimensionally and connected to RF switches. The length of each transmitter (Tx) and receiver (Rx) channel differs slightly, causing artifacts in high-resolution image reconstruction. This study presents a novel method for the phase calibration of multistatic systems. This method does not require system reconstruction and can automatically perform phase calibration in a short time. This method is expected to facilitate an accurate phase measurement in multistatic systems. The approach involves phase calibration by analyzing the reflection coefficients of antenna elements in the time domain. Imaging experiments were performed on a multistatic imaging system using this calibration method, and the position and shape of a metal rod with a diameter one-fourth of a wavelength were reconstructed by simple back-projection with an accuracy beyond the diffraction limit.

Understanding the dispersion of floating objects and ocean properties at the ocean surface is crucial for various applications, including oil spill management, debris tracking and search and rescue operations. While mesoscale turbulence has been recognized as a primary driver of dispersion, the role of submesoscale processes is poorly understood. This study investigates the largely unexplored mechanism of dispersion by refracted wave fields. In situ observations demonstrate significantly faster and distinct dispersion patterns for objects influenced by wind, waves and currents compared to those solely driven by ocean currents. Numerical simulations of wave fields refracted by ocean eddies corroborate these findings, revealing diffusivities that exceed those of turbulent diffusion at scales up to 10 km during energetic sea states. Our results highlight the importance of ocean waves in dispersing surface material, suggesting that refracted wave fields may play a significant role in submesoscale spreading. As atmospheric forcing at the ocean surface will only strengthen due to anthropogenic contributions, additional research into wave refraction is necessary. This requires concurrent high-resolution measurements of wind, waves and currents to inform the revisions of large-scale coupled models to better include the submesoscale physics.

A Rotary-Pulsation Apparatus (RPA), also known in the literature as a Rotational Hydrodynamic Cavitation Reactor (RHCR), is a device which typically consists of a rotating mechanism that generates pulsations or vibrations within a fluid. This can be achieved through various means such as mechanical agitation, pneumatic pulses, or hydraulic forces. It is widely used in food, chemical, pharmaceutical, and microbiological industries to improve the mixing of different fluids, dispersion, pasteurization, and sterilization. In the present paper, a CFD study was conducted to develop and optimize the geometry of the RPA’s rotor and stator to induce cavitation in the fluid flow. The effect of cavitation has the potential to improve dispersion and emulsion properties and to significantly reduce operation pressure, in comparison to conventional mixing systems.

Several models exist for predicting dilution from large rooftop exhausts, but their validity has not been assessed for horizontally directed through-wall exhausts such as those that often exist in new multi-family residential construction. Separation distances derived from rules of thumb or simplified versions of these models are prescribed in ventilation standards, but their appropriateness has not been assessed and they are sometimes difficult to achieve in practice. In order to provide more justifiable separation distances, we conducted a series of wind tunnel experiments and computational fluid dynamics (CFD) simulations measuring dilution of a horizontally-directed exhaust from a test building. We then compared these measurements to existing models and assessed the models’ validity for this situation. Lastly, we gathered dilution criteria for several contaminants of interest and used wind tunnel and CFD results along with published emission rates to specify a separation distance that is likely to result in acceptable air quality at neighboring intakes. Results show that mitigation of chronic health concerns from cooking, and smoking in dwelling units, as well as odor concerns from bathrooms, can likely be achieved with separation distances of 5 feet or less. To prevent irritation from smoking in neighboring units, a separation distance of 10 feet is recommended. We did not find that furnace exhaust can be diluted sufficiently with separation distances that are feasible on multi-family buildings.