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In order to investigate the reproductive dynamics of the ichthyofauna in the Brazilian Pantanal, this study examines the spatial and temporal distribution of ichthyoplankton, taxonomic composition, and its correlation with environmental factors within one of the most important sub‐basins, the Taquari River. Egg and larvae collections were conducted at 11 sampling points between October and March of 2017/2018 and 2018/2019. Significant differences were observed between collection points, months, and years, with higher ichthyoplankton densities in the Coxim and Taquari rivers, particularly between November and January. Twenty‐eight genera and/or species of fish were identified, including 10 long‐distance migratory species. Egg density showed a negative correlation with water temperature and rainfall. For larvae, water transparency and rainfall were both significant, negatively influencing larval abundance. However, different species tend to occur in environments with distinct abiotic qualities. Yolk‐sac, preflexion, and flexion larval development stages were distributed throughout the sub‐basin, especially near the Pantanal. Considering the data and analyses presented in this study, the importance of connectivity between these environments, specifically between the plateau and Pantanal, is evident, highlighting the significance of the entire sub‐basin for fish reproductive processes. Therefore, research focusing on the ecological processes influencing the distribution of ichthyoplankton offers valuable insights for ecosystem conservation and aids in effective environmental management. [ABSTRACT FROM AUTHOR]

Hydrogen is an ideal energy source and plays an important role in increasingly global energy issues and environmental problems. Liquid hydrogen (LH2) has many advantages over other storage methods, especially in terms of energy density. However, it may cause enormous harm once it leaks accidently. LH2 leakage is a complex multiphase process involving evaporation, condensation, transfer of mass and heat, and dispersion. In order to study LH2 transportation and storage systems safety, a research project has been carried out to develop a 3D numerical model using an open-source CFD code, OpenFoam, for investigating LH2 accidental release scenarios. Since the release of LH2 is a very complex process, our strategy is to study it step by step. Therefore, in this paper we present our research work at the first stage, a dispersion process of room-temperature gaseous hydrogen without multiphase flow. A small-scale hydrogen release conducted by Sandia National Laboratories is simulated. In this experiment, room-temperature gaseous hydrogen is injected upwards into the air from a small hole with a 1.91 mm diameter. The situations of Froude (Fr) number = 99, 152, and 268 are studied, respectively. The behavior of hydrogen at different Fr numbers is discussed. When high-speed hydrogen enters the air, the speed and concentration of hydrogen decrease rapidly. In addition, the greater the speed, the faster it decays. The result shows a close range of hydrogen reach. Details about the numerical model are introduced. The simulation results are used to verify the validity of the developing numerical model for dispersion and mixing of multi-species. The simulated concentrations and velocity distribution are analyzed and compared with experimental data. The simulation shows a good agreement with the data of Sandia National Laboratories. The agreement between experiments and simulations is measured using the Pearson correlation coefficient (>0.98), which indicates excellent consistency. In the next step, we will integrate the multiphase flow and phase change into the current model. The phase change of liquid hydrogen and air will be simulated to study the release of liquid hydrogen. • Using the open-source CFD code OpenFOAM for simulation of hydrogen jet. • A good agreement between the simulations results and experimental data has been found in this paper. • When high-speed hydrogen is injected into the air, both velocity and concentration drop rapidly. • Final concentration is not sensitive to different injection velocity. [ABSTRACT FROM AUTHOR]

Accurate calculation of non-covalent interaction energies in nucleotides is crucial for understanding the driving forces governing nucleic acid structure and function, as well as developing advanced molecular mechanics forcefields or machine learning potentials tailored to nucleic acids. Here, we dissect the nucleotides' structure into three main constituents: nucleobases (A, G, C, T, and U), sugar moieties (ribose and deoxyribose), and phosphate group. The interactions among these fragments and between fragments and water were analyzed. Different quantum mechanical methods were compared for their accuracy in capturing the interaction energy. The non-covalent interaction energy was decomposed into electrostatics, exchange-repulsion, dispersion, and induction using two ab initio methods: Symmetry-Adapted Perturbation Theory (SAPT) and Absolutely Localized Molecular Orbitals (ALMO). These calculations provide a benchmark for different QM methods, in addition to providing a valuable understanding of the roles of various intermolecular forces in hydrogen bonding and aromatic stacking. With SAPT, a higher theory level and/or larger basis set did not necessarily give more accuracy. It is hard to know which combination would be best for a given system. In contrast, ALMO EDA2 did not show dependence on theory level or basis set; additionally, it is faster. [ABSTRACT FROM AUTHOR]

The Lamb waves in nematic elastomer plates are investigated by adopting the viscoelasticity theory in the hydro-dynamic (low frequency) limit. The Legendre polynomial series approach is employed to obtain the complex wave number solutions to characterize the wave propagation and attenuation. Some unique Lamb wave characteristics are revealed. Results show that the cutoff frequencies of all Lamb modes vanish due to the high viscoelasticity. Except for A0 mode, each mode has a minimal attenuation frequency. Besides, the attenuation of nematic phase is thousands of times greater than the isotropic phase, which would be significant in designing damping applications. [ABSTRACT FROM AUTHOR]

Motivated by important applications to the analysis of complex noise-induced phenomena, we consider a problem of the constructive description of randomly forced equilibria for nonlinear systems with multiplicative noise. Using the apparatus of the first approximation systems, we construct an approximation of mean square deviations that explicitly takes into account the presence of multiplicative noises, depending on the current system state. A spectral criterion of existence and exponential stability of the stationary second moments for the solution of the first approximation system is presented. For mean square deviation, we derive an expansion in powers of the small parameter of noise intensity. Based on this theory, we derive a new, more accurate approximation of mean square deviations in a general nonlinear system with multiplicative noises. This approximation is compared with the widely used approximation based on the stochastic sensitivity technique. The general mathematical results are illustrated with examples of the model of climate dynamics and the van der Pol oscillator with hard excitement. [ABSTRACT FROM AUTHOR]

This study investigates the efficiency of already developed surface‐modified carbon black (CB), both independently and in conjunction with nano‐silica, as a hybrid filler, to the properties of natural rubber (NR) compounds. The modification process, followed by coupling agent treatment, enhanced cross‐link density and curing characteristics, though the inclusion of nano‐silica alone negatively affected curing due to its inherent polarity and tendency to agglomerate. The filled compounds with modified CB exhibited significant improvements in mechanical properties, notably tear resistance. Moreover, the combination of nano‐silica with modified CB yielded compounds with superior tear resistance, attributed to synergistic effects. CB surface modification exhibited varying effects on the glass transition temperature, with enhancements observed in tan δ at lower temperatures, indicating improved ice and wet grip potential. Also, it reduced rolling resistance after treatment with a coupling agent. While thermal stability remained consistent across the studied compounds, swelling resistance varies with filler type and ratio. Thermodynamic analysis confirmed the positive impact of CB surface modification on the elasticity and chain mobility of the investigated rubber compounds. It was concluded that the strategic selection of fillers and modification approaches were essential for achieving optimal results in the rubber compound's performance and application. [ABSTRACT FROM AUTHOR]

Control charts are widely used in the manufacturing and service sectors to track, regulate, and enhance process output. A manufacturing industry desires to utilize a control chart that has an effective structure and is sensitive to detect infrequent variations in the process. Generally, control charts are developed with the presumption that the understudy quality variable is normally distributed. In actual application, many processes have skewed distributions. The purpose of this study is to use the moving average (MA) charts to track the dispersion of a log‐normal distribution. The design of the proposals is developed and the performance is assessed by run‐length properties. The cumulative distributions of run‐length under in‐control and out‐of‐control are provided to have a broad view of the performance. The simulation findings show that when the value of the log‐normal dispersion parameter is large, the proposed chart is more sensitive to the changes in the dispersion. Additionally, an industrial application is given to illustrate the suggested charts in this research. [ABSTRACT FROM AUTHOR]

To enhance our understanding of electroporation and optimize the pulses used within the frequency range of 1 kHz to 100 MHz, with the aim of minimizing side effects such as muscle contraction, we introduce a novel electrical model, structured as a 2D representation employing exclusively lumped elements. This model adeptly encapsulates the intricate dynamics of living cells' impedance variation. A distinguishing attribute of the proposed model lies in its capacity to decipher the distribution of transmembrane potential across various orientations within living cells. This aspect bears critical importance, particularly in contexts such as electroporation and cellular stimulation, where precise knowledge of potential gradients is pivotal. Furthermore, the augmentation of the proposed electrical model with the Hodgkin-Huxley (HH) model introduces an additional dimension. This integration augments the model's capabilities, specifically enabling the exploration of muscle cell stimulation and the generation of action potentials. This broader scope enhances the model's utility, facilitating comprehensive investigations into intricate cellular behaviors under the influence of external electric fields. In our research, we've introduced an enhanced electrical model for living cells. This model simplifies cell behavior using only basic electrical components like resistors and capacitors. It's designed to mimic the real electrical properties of cells, particularly the cell membrane, which can change in response to electricity at different frequencies, ranging from 1 kHz to 100 MHz. This frequency range is essential for studying processes like electroporation, a technique used in various medical applications. Our model is represented in a two-dimensional structure, making it a handy tool for identifying transmembrane potential distributions, a critical factor in electroporation procedures. This means we can better understand how cells react to electrical impulses, which is crucial for improving electroporation techniques. Additionally, we've extended our model to include muscle cells by incorporating the Hodgkin-Huxley model, a well-established model for understanding electrical behavior in muscle cells. This allows us to study how muscles contract when exposed to different electrical pulses, a common side effect of electroporation procedures. By examining various pulse characteristics, we can determine which ones are best for minimizing muscle contractions during electroporation. In summary, our research has led to the development of a versatile electrical model for living cells. It not only helps us understand how cells respond to electricity in the context of electroporation but also provides insights into muscle contractions and how to optimize electrical pulses for medical treatments. [ABSTRACT FROM AUTHOR]

The transdermal drug delivery system (TDDS) was created with the main goals of achieving extended pharmaceutical release, increasing bioavailability, and enhancing patient adherence. The matrix dispersion transdermal patch works by dispersing the drug and polymers in a solvent, which is then evaporated to leave a homogenous drug-polymer matrix. The goals of the present study were on designing and formulating TDDS for tirzepatide and afterwards assessing their in vitro performance characteristics. In diabetes mellitus, the pancreas either produces inadequate amounts of insulin or the body is unable to properly use the insulin that is generated. More than 415 million people worldwide have diabetes, and it is anticipated that by 2040, that number would reach 642 million. By 2030, diabetes will surpass heart disease as the seventh largest cause of death, according to the WHO. [ABSTRACT FROM AUTHOR]

The article is devoted to the study of the process of removing moisture from capillary-porous materials by its dispersion during the collapse of cylindrically-shaped cavitation bubbles formed in the capillaries of the material under ultrasonic exposure. A model has been proposed and developed that made it possible to explain the mechanism of dispersion during realization of the life cycle of a bubble in a capillary — slow growth, rapid expansion with deformation, and subsequent collapse. The range of sound pressure levels at which dispersion begins (from 150 dB) to the level at which bubbles reach the size of the capillary and the increase in the drying efficiency stops (170 dB) has been determined theoretically. It was also shown that for maximum efficiency in moisture removal, the size of the dehydrated sample must correspond to the ultrasonic wavelength in air. The mechanism of ultrasonic dispersion of liquid during drying has been confirmed experimentally and it has been established that to reduce the drying time by more than 40%, exposure with a level in the range of 165–170 dB is necessary, and the dried materials must be placed in the form of particles or layers having dimensions or thicknesses corresponding to the ultrasonic wave length. The practical implementation of ultrasonic drying using the example of food products (red beets) confirmed the effectiveness of the proposed mechanism and ensured a reduction in drying time by 1.9 times on reducing energy demand by 1.6 times. [ABSTRACT FROM AUTHOR]

External transient impact loads widely exist in the service environment of various engineering structures, and urgent engineering and military application requirements call for research on the theory and method of impact identification. This manuscript proposes a method to identify the impact event. By employing the dispersive property of wave propagation through the waveguides, a dispersion-based average power spectral density (PSD) curve for quantitative representation of the dispersion is established, and its evolution law is investigated to apply the identification of impact events. The critical parameters of the average PSD curve are obtained by analyzing the response of the structure from the perspective of mechanics. The effectiveness of this method is verified through the development of the triple-successive-impact split Hopkinson bar and the triple-successive-impact experiment. Through the method proposed in this manuscript, a kind of impact identification under multiple impact loads, which is not convenient to measure directly by the sensor, is realized, especially in the case of highly transient external impact. [ABSTRACT FROM AUTHOR]

The high specific stiffness materials are used to design the space payload components. These components should sustain the extreme environmental condition throughout their life cycle without failure. The prerequisites of future space missions need lightweight materials which must be mechanically strong and high thermal and electrically conductive. The Carbon Nanotubes (CNTs) are efficient filler material in composite or metal matrix to enhance greater electrical and thermal conductivity. The quality of the CNT nano composite relies upon several parameters like the types of CNTs, its purity, aspect ratio, amount of loading, alignment, and interfacial adhesion between the nanotube and polymer. The performance of the CNT-CFRP composite depends on the successful execution of the processing technique. This review paper intends to highlight the enhancement of the mechanical, thermal, electrical properties of the composite, and the challenges to achieving it. This review paper helps to optimise the process parameters to fabricate Space Payload Components, required to replace existing high-density Space Qualified Materials. This review paper should help optimize the process parameters to fabricate Space Payload Components, which can be excellent alternatives to the existing high-density Space Qualified Materials without making any compromise on the performance index. [ABSTRACT FROM AUTHOR]

The present study examines the impacts of saponin, extracted from the fruits of Acacia Concinna, in its effectiveness as a dispersant and stabilizer during the pipeline conveyance of iron ore particles. The basic fundamental characteristics of iron ore, which comprises a majority of hematite and has a size of (≤75 µm), have been examined and characterized. Iron ore water slurry (IWS) rheological behavior has been investigated as a function of saponin doses, pH, particle concentration, and the shear rate-shear stress correlation. The change in zeta potential with pH is used to compute the isoelectric point of IWS. An appropriate mechanism has been presented to explicate the interaction between saponin and particles of Iron ore. The surface-modified particles exhibit improved dispersion characteristics in the aqueous solution due to the modification of electrostatic force that the surface charge on each particle causes. Investigation indicates that the optimal proportion of saponin had a significant favorable effect on the fluidity and stability of the suspension. The analysis of the economic impact of the dispersant has been conducted through the evaluation of slurry head loss and specific energy consumption (SEC) pertaining to the implementation of the IWS pipeline in its intended commercial application. [ABSTRACT FROM AUTHOR]

The efficient dispersion of single-walled carbon nanotubes (SWCNTs) has been the subject of extensive research over the past decade. Despite these efforts, achieving individually dispersed SWCNTs at high concentrations remains challenging. In this study, we address the limitations associated with conventional methods, such as defect formation, excessive surfactant use, and the use of corrosive solvents. Our novel dispersion method utilizes the spontaneous charging of SWCNTs in a solvated electron system created by dissolving potassium in hexamethyl phosphoramide (HMPA). The resulting charged SWCNTs (c-SWCNTs) can be directly dispersed in the charging medium using only magnetic stirring, leading to defect-free c-SWCNT dispersions with high concentrations of up to 20 mg/mL. The successful dispersion of individual c-SWCNT strands is confirmed by their liquid-crystalline behavior. Importantly, the dispersion medium for c-SWCNTs exhibits no reactivity with metals, polymers, or other organic solvents. This versatility enables a wide range of applications, including electrically conductive free-standing films produced via conventional blade coating, wet-spun fibers, membrane electrodes, thermal composites, and core-shell hybrid microparticles. [ABSTRACT FROM AUTHOR]

The dispersion behaviour of the finite element method, applied to the treatment of stress wave propagation tasks in an elastic solid continuum, is reviewed and complemented with the authors' contributions in the field, along with substantial details of finite element technology. It is shown how finite element dispersion disqualifies to a certain extent the stress wave propagation modelling and, as such, cannot be completely eradicated. The paper, however, reveals the ways how the dispersion effect (actually, modelling errors) could be minimized. The effects of spatial and temporal dispersions of the finite element method are treated. 1D and 2D linear and quadratic finite elements and their suitability are analysed for use with implicit and explicit integration methods. Historical as well as new, up-to-date approaches are also reviewed. The paper closes with recommendations for values of mesh size and timestep size, mass matrices and direct time integrations with respect to dispersion errors in finite element modelling of elastic wave propagation problems in solids. [ABSTRACT FROM AUTHOR]

This study aims to investigate the utilization of wheat straw (WS) as a filler in a rubber compound consisting of a blend of natural rubber (NR). The NR blend was prepared using a mixing mill operating at 80°C and 50 rpm, with varying weight fractions (parts per hundred rubber) of WS (0-5-15-25pphr) and particle sizes ranging from 250-500 µm. The incorporation of WS into the matrix resulted in a decrease in tensile strength and viscosity, while the tensile modulus and hardness exhibited an opposite trend. This can be attributed to the weak interaction between the filler and matrix, leading to inadequate filler dispersion and the formation of large agglomerated particles. However, certain mechanical properties of the rubber compound showed slight improvements upon the addition of WS, while others experienced a decrease. Overall, the rheological properties of all samples remained relatively changed. [ABSTRACT FROM AUTHOR]

This research studies rogue wave solutions with center parameters of a generalized (3+1)-dimensional KdV-type equation in plasma physics. Using a direct generalized formula and symbolic technique, it creates rogue waves with adjustable dynamical characteristics controlled by the center parameters. Our investigation produces rogue wave solutions up to the third order with Painlevé transformation through direct computation, considering a range of center-controlled and other parameters within the investigated equation. To facilitate our analysis, we derive an equation for the function f in bilinear form, utilize the Cole-Hopf transformation for the wave function u, and introduce the transformed variable ζ . It obtains the rogue wave solutions using a generalized form for N-rogue waves generated from Hirota's N-soliton approach. Through the powerful symbolic computation tool Mathematica, we provide visualizations of the dynamic behavior of rogue waves across diverse center parameters. This research highlights the prevalence of massive rogue waves within nonlinear phenomena, showcasing their dominance over their smaller counterparts. The investigated equation offers insights into the evolution of longer waves characterized by smaller amplitudes, which is particularly relevant in plasma physics, fluid dynamics, and dispersive media. Rogue waves have applications in diverse scientific fields, including oceanography, nonlinear dynamics, fluid dynamics, fiber optics, dusty plasma, and complex nonlinear systems [ABSTRACT FROM AUTHOR]

This article discusses financial stability related notions of risk, the issue of convergence and cross financial sector prudential intervention. It elucidates the Basel framework shortcomings and enunciates the requirement of setting a reinvigorated prudential framework before proceeding to its essentials in terms of engineering. It highlights an early warning approach dealing with the issue of time reaction mismatch of the prudential authority and the priority of setting a long run forwarded guided approach. The objective of this research is to provide a clue into enhancing prudential setting of instruments, the forwarded guided purview of surveillance as well as hedging and the Balanced Score Card. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office 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.)

Low Stokes number particles at dilute concentrations in turbulent flows can reasonably be approximated as passive scalars. The added presence of a drift velocity due to buoyancy or gravity when considering the transport of such passive scalars can reduce the turbulent dispersion of the scalar via a diminution of the eddy diffusivity. In this work, we propose a model to describe this decay and use a recently developed technique to accurately and efficiently measure the eddy diffusivity using Eulerian fields and quantities. We then show a correspondence between this method and standard Lagrangian definitions of diffusivity and collect data across a range of drift velocities and Reynolds numbers. The proposed model agrees with data from these direct numerical simulations, offers some improvement to previous models in describing other computational and experimental data and satisfies theoretical constraints that are independent of Reynolds number. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced thermoplastic composites have such advantages as low density, high strength, high temperature resistance, impact resistance, and good ductility, but due to the density difference between carbon fibers and resin fibers, it is difficult to mix them uniformly. Hence, it is difficult to prepare the composites with the uniform properties. In order to solve this problem, a preparation process based on solid phase mixing of carbon and resin fibers by suspension method is proposed in this paper. The carbon fiber reinforced thermoplastic composites (CFRTPs) can be prepared by dispersing carbon fibers of a certain length (~50 mm) and resin fibers in suspension through ultrasound‐assisted and churn‐combing methods. The effects of carbon fiber length, content and molding process on the mechanical properties of the CFRTPs were studied. The results show that the carbon fiber content and length are the main factors affecting the mechanical properties as well as void ratio of CFRTP. The performance of composites is significantly improved with the increase of carbon fiber length. While the length of carbon fiber is 50 mm and the content is 30 wt%, the prepared CFRTP has the best performance, with the tensile strength of 182.1 MPa, the bending strength of 354.3 MPa, the impact strength of 67.2 KJ·m−2, and the material void ratio of 0.65%. The study shows that the suspension method is feasible for the preparation of the CFRTPs. It is beneficial to improve production efficiency and decrease cost of production for the CFRTPs. Highlights: Carbon fiber reinforced thermoplastic composites can be prepared by dispersing carbon fibers of a certain length (~50 mm) and resin fibers in suspension through ultrasound‐assisted and churn‐combing methods.Through the cooling‐high pressure molding process, the porosity of CFRTP is reduced and the mechanical properties of CFRTP are improved.The tensile strength, bending strength, and notch‐free impact strength properties of CFRTP are best when the carbon fiber content is 30% and the CF length is 50 mm.The method is characterized by simple process, low cost and high mechanical properties. [ABSTRACT FROM AUTHOR]

Laponite® (LAP) is an intensively studied synthetic clay due to the versatility given by its layered structure, which makes it usable in various applications. This review describes the multifaceted properties and applications of LAP in aqueous dispersions and gel systems. The first sections of the review discuss the LAP structure and the interactions between clay discs in an aqueous medium under different conditions (such as ionic strength, pH, temperature, and the addition of polymers) in order to understand the function of clay in tailoring the properties of the designed material. Additionally, the review explores the aging phenomenon characteristic of LAP aqueous dispersions as well as the development of shake-gels by incorporating LAP. The second part shows the most recent studies on materials containing LAP with possible applicability in the drilling industry, cosmetics or care products industry, and biomedical fields. By elucidating the remarkable versatility and ease of integration of LAP into various matrices, this review underscores its significance as a key ingredient for the creation of next-generation materials with tailored functionalities. [ABSTRACT FROM AUTHOR]

Left-handed materials are known to exhibit exotic properties in controlling electromagnetic fields, with direct applications in negative reflection and refraction, conformal optical mapping, and electromagnetic cloaking. While typical left-handed materials are constructed periodic metal-dielectric structures, the same effect can be obtained in composite guest–host systems with no periodicity or structural order. Such systems are typically described by the effective-medium approach, in which the components of the electric permittivity tensor are determined as a function of individual material properties and doping concentration. In this paper, we extend the discussion on the mixing rules to include left-handed composite systems and highlight the exotic properties arising from the effective-medium approach in this framework in terms of effective values and dispersion properties. [ABSTRACT FROM AUTHOR]

Most species-rich communities consist of a limited number of common species and many rare species. This widespread ecological pattern can arise due to the predominance of either niche-based or neutral-based processes in community structuring. We tested two hypotheses related to this pattern for an anuran metacommunity composed of 35 species distributed in 187 ponds in the South Brazilian grasslands: (1) for common species, niche processes should prevail over neutral ones because common species evolved under a wider range of ecological filters than rare species; (2) for rare species, neutral processes should prevail because rare species are more prone to ecological drift and dispersion limitation. We found that the densities of both common (i.e., the 25% higher density ones) and rare (i.e., the 75% lower density ones) species depended mostly on pond structure and land use, indicating a similar response to niche-based processes in both groups of species. The importance of pond descriptors and type of land use, however, differed between the two groups, confirming that common and rare species represent ecologically distinct groups within the metacommunity. In addition, neutral processes—related to dispersion limitation or not—influenced both species groups, but the spatial filters selected explained a smaller portion of the variation in species densities compared to environmental descriptors. Our findings showcase the prevalence of niche processes in structuring communities of common and rare species of anurans in subtropical grasslands and indicate the variables of pond structure and land use that are relevant to guide conservation practices for the metacommunity of anurans in the South Brazilian grasslands. [ABSTRACT FROM AUTHOR]

Broadly speaking, prediction of the negative impacts of prescribed fire on air quality is limited by gaps in our understanding of the underlying fire, fuels, and atmospheric processes. These knowledge gaps hinder our ability to accurately predict smoke concentration distributions, leading to unintended smoke intrusions into nearby communities and subsequent threats to public health and safety. In this study, numerical simulations are performed using the Flexible Particle Weather Research and Forecasting (FLEXPART-WRF) Model, a Lagrangian particle dispersion model, with particle motion driven by output from a full-physics atmospheric model with a forest canopy submodel and 10-m horizontal grid spacing [Advanced Regional Prediction System (ARPS)-CANOPY], to address two research questions. First, what is the relationship between near-fire (within ∼50–150 m of fire) smoke concentration distribution and (i) vertical canopy structure and (ii) fire heat source strength? Second, what roles do mean transport (i.e., transport by the mean wind) and turbulent diffusion play in shaping the near-fire smoke concentration distribution? To address these questions, simulations are run with 25 combinations of plant area density profile and fire sensible heat flux magnitude, and smoke is represented by particles with diameters ≤ 2.5 μm (PM2.5). Results show that near-fire PM2.5 concentration distribution is primarily controlled by vertical canopy structure, with fire heat source strength primarily controlling the PM2.5 concentration magnitude. Analysis of the underlying ARPS-CANOPY variables driving the FLEXPART-WRF particle dispersion helps elucidate the roles of mean transport and turbulent diffusion. In total, the study findings suggest that the vertical distribution of canopy vegetation and fire heat source strength are important factors influencing PM2.5 dispersion and concentration distribution near low-intensity fires. [ABSTRACT FROM AUTHOR]

The current paper recovers optical solitons for the dispersive concatenation model with polarization-mode dispersion. The complete discriminant approach has made this retrieval possible. The intermediary Jacobi's elliptic functions gave way to the soliton solutions, with the limiting approach applied to such functions. These solitons are classified, and their surface and contour plots are sketched. [ABSTRACT FROM AUTHOR]

Count data are common in practice. Statistical process control for count data thus has attracted much attention in recent years. Most existing methods on this topic focus on the detection of mean shifts of count data based on parametric modeling. However, their assumed parametric models (e.g., the Poisson probability model) are often invalid in practice due mainly to the potential impact of some latent confounding risk factors, which would lead to unreliable performance of the related control charts. In addition, it is highly desirable and important to monitor the dispersion of count data when the Poisson probability model is invalid. To this end, new nonparametric cumulative sum control charts and their corresponding self‐starting versions are suggested in this paper for monitoring the dispersion of count data based on data categorization and categorical data analysis. Numerical results show that the proposed method can provide more effective and robust monitoring of count data in comparison with some representative existing methods. A real‐data example is used to demonstrate its implementation and application. [ABSTRACT FROM AUTHOR]

Pedigrees used in genetic evaluations contain errors. Because of such errors, assumptions regarding the relatedness among individuals in genetic evaluation models are wrong. Consequences of that have been investigated in earlier studies focusing on models that did not account for genomic information yet. The objective of this work was to investigate the effects of pedigree errors on the results from genetic evaluations using the single-step model, and the effect of such effects on results from validation studies with forward prediction. We used a real pedigree (n = 361,980) and real genotypes (n = 25,950) of Fleckvieh cattle, sampled in a way to provide a good consistency between pedigree and genomic relationships. Given the real pedigree and genotypes, true breeding values (TBV) were simulated to have a covariance structure equal to the matrix H assumed in a single-step model. Based on TBV, phenotypes were simulated with a heritability of 0.25. Genetic evaluations were conducted with a conventional animal model (i.e., without genomic information) and a single-step animal model under scenarios using either the correct pedigree or a pedigree containing 5%, 10%, or 20% of wrong records. Wrong records were simulated by randomly assigning wrong sires to nongenotyped females. The increasing rates of pedigree errors led to decreasing correlations between TBV and EBV and lower standard deviations of predictions. Less variation was observed because pedigree errors operate actually as a random exchange of daughters among bulls, making them look more similar to each other than they actually are. This occurs of course only when animals have progeny. Therefore, this decreased variation was more pronounced for progeny tested bulls than for young selection candidates. In a forward prediction validation scenario, the stronger decrease in variation when animals get progeny caused an apparent inflation of early predictions. This phenomenon may contribute to the usually observed problem of inflation of early predictions observed in validation studies. [ABSTRACT FROM AUTHOR]

In this paper, the dispersion of Carbon nanomaterials (CNMs) in an electrolytic solution containing cations such as Ca2+, Al3+, Na+, and Mg2+ with different types of superplasticizers (Sika, Master Ease 3502, Prime DC, and Prime Flow) have been investigated. Further, the stabilized CNMs along with different superplasticizers (Sps) incorporated into the cementitious mortar and studied their mechanical strength. The influence of Sps on the stability of CNMs in an aqueous medium has been monitored by UV-Visible spectroscopy. The study concludes that Sika Sp was the best dispersant for the CNMs dispersion in an aqueous medium. The de-stability of the CNMs has followed this trend of the agglomerations in the electrolytic solution as Al3+>Ca2+>Mg2+>Na+. The Sika Sp has great dispersant properties as well as provides a homogeneous distribution of CNMs in a cementitious matrix which was supported by FE-SEM analysis. The addition of SIKA@PPC-GO (GO about 0.0015% by weight of cement) and SIKA@PPC-FCNTs (FCNTs about 0.0015% by weight of cement) results in enhancement of cement 11.67%, 8.73% for compressive and 26.35, 20.61% for tensile strength respectively, at the curing ages of 90 days. This investigation may provide advanced knowledge to predict the stability of CNMs in superplasticizer-based solutions. [ABSTRACT FROM AUTHOR]

A systematic study has been performed for the effect of nonionic surfactants (NSs), i.e., ethoxylated higher fatty alcohols with different ethoxylation degrees, on the ultrasonic dispersion of carbon nanotubes in aqueous solutions and on the colloid-chemical properties of the resulting dispersions, namely, their optical density and the sizes and electrokinetic potentials of the particles in the colloidal systems. A non-linear dependence of the characteristics of dispersions on the ethoxylation degree has been revealed. This dependence is associated with structural transformations in NS molecules. The most efficient ethoxylation degree and concentration of nonionic surfactants in a solution, which have the highest disaggregating and stabilizing effects upon the preparation of carbon nanotube (CNT) dispersions, have been determined. The influence of the ethoxylation degree of the ethoxylated higher fatty alcohols on the electrokinetic properties of CNT dispersions has been revealed. It has been shown that carbon nanotube dispersions can be used to modify the rheological and electrical properties of gel systems based on rarely crosslinked poly(acrylic acid). The effects of NSs and CNTs on the viscosity, shear yield stress, consistency index, mechanical stability, relaxation time, and viscous flow activation energy of the polymer gels have been studied. It has been shown that the incorporation of nanotubes increases the electrical conductivity of the gels. The ultrastructure of the gel samples has been studied by transmission electron microscopy. [ABSTRACT FROM AUTHOR]

Dispersion analysis of acoustic guided waves, propagating in a stratified medium, containing an internal sandy layer in contact with the isotropic elastic substrate and the upper elastic isotropic layer, is developed by applying the modified Cauchy formalism coupled with the exponential fundamental matrices and the Thomson–Haskell transfer matrix method. The developed approach is suitable for analyzing dispersion properties of guided waves at the broad variation of the sandy parameter. Several phenomena, concerning anomalous dispersion of guided waves at varying sandy parameter, are observed, revealing the possibility of nondestructive evaluation of sandy layers within the upper crust. [ABSTRACT FROM AUTHOR]

It is known that Lamb waves in homogeneous traction-free plates can propagate with arbitrary phase velocity, spanning the admissible speed interval (0; + ∞) . However, as the current research shows, Lamb waves propagating in two-layered traction-free plates may have 'forbidden' phase velocities, at which no Lamb waves can propagate. The analysis is based on the approach comprising Cauchy complex formalism and the exponential fundamental matrix method. [ABSTRACT FROM AUTHOR]

Hydroxy azo‐benzenes are very well known for their rapid trans⇆cis photoisomerization under polar solvents. In contrast, we synthesized two hydroxymethylated‐ hydroxyazobenzene derivatives and investigated their light‐triggered photoisomerization and stability under polar solvents. The result showed just opposite behavior and very slow trans⇆cis isomerization was observed (minutes‐days). Thus, the UV‐vis spectrum revealed a very low decrease in the absorbance of π–π* transition. Surprisingly, the isomerization process became faster with the addition of ionic species. Here, we attempted to understand the underlying cause of the unusual photo‐switching behavior. The presence of hydroxymethyl and fluorine substituents was found to have a significant effect on the stability of the trans and photo‐isomerized cis products. Here, it was confirmed with NMR and DLS studies that the unusual photostability of trans compounds was caused by polar solvent‐assisted aggregation (hydrodynamic radius, RH 5660–1720 nm) which underwent dispersion (RH, 220–68 nm) and formed a significant stable solvated photoproduct under photoirradiation. Furthermore, this aggregation‐dispersion was found to be very slowly reversible. Further, the fluorescence emission demonstrated a characteristic dispersion‐induced quenching. Regular photoswitching was observed under non‐polar conditions in benzene where an expected blue shift of π–π* transition and an increase in the intensity of n–π* transitions. [ABSTRACT FROM AUTHOR]

The proper Dirac-like cones are observed in dispersion portraits of guided waves propagating in isotropic three-layered traction-free plates. It is revealed that if both layers have equal Poisson's ratios and satisfy Wiechert condition, the Dirac-like cones appear regardless of the Poisson's ratio value. This phenomenon opens a new approach for the creation of the layered plates possessing Dirac-like cones. The analysis is based on the Cauchy sextic formalism combined with the exponential fundamental matrix method. [ABSTRACT FROM AUTHOR]

The native savanna ecosystem of the Orinoquia region is the habitat of 50% of the wild ungulate species reported for Colombia. Over the last 20 years, this high species diversity has been strongly threatened by the human transformation of the natural land cover causing connectivity loss of the habitats. The Orinoquia region lacks a biological connectivity analysis with a multi-species approach involving species groups that are representative of the savanna ecosystem such as the ungulates. Understanding the spatial distributions of suitable areas and the main habitats that act as primary habitats for ungulate species in these landscapes is fundamental for the design of conservation strategies. We use an occurrence dataset for lowland tapir (Tapirus terrestris), white-tailed deer (Odocoileus virginianus), and white-lipped peccary (Tayassu pecari) in the development of species' potential distribution models, binarization process, and morphological spatial pattern analysis. This information was used for the modeling of dispersal corridors connecting the core habitats of the ungulate focal species using the randomized shortest path algorithm and quantifying the weighted global connectivity metrics. Our results suggest an integral corridor with potential least-cost dispersal routes between the native savanna landscape on the middle basins of the savanna rivers and the Meta River. These areas associated with the fluvial dendritic systems are connected, while the core habitats in the eastern part of the savanna landscape are disconnected. We discuss how the application of such knowledge on the spatial ecology of ungulate focal species might improve the management of the metapopulations in the Orinoquia region. [ABSTRACT FROM AUTHOR]

Rapid urbanisation has led to a remarkable increase in travel demand as well as the number of vehicles globally. Inadequate road networks, especially in developing countries fail to serve this increasing vehicle population resulting in frequent traffic congestion. Proportional vehicular emissions are found to be responsible for serious consequences on human health and the environment. The nature and impact of these emissions depend on the traffic, environmental and meteorological factors. The present study focuses on vehicular emissions in a typical identified urban road stretch. The dispersion of vehicular pollutants in the selected urban stretch was studied using Fluidyn PANACHE version 5.2.6 software. The analysis of dispersion revealed that the highest concentration of pollutants is observed along the road sections, with a gradual decrease in concentration as you move away from the streets in both directions. From the vertical profile plotted, the maximum concentration is found to be on the ground and decreases as the height increases, which reveals the influence of meteorological parameters on urban air quality. These results indicate the significant influence of vehicular emissions and meteorological characteristics on ambient air quality. [ABSTRACT FROM AUTHOR]

Frugivory and seed dispersal are fundamental processes for biodiversity, especially in forest environments, which are increasingly fragmented and scarce. Bats are crucial seed dispersers due to the large number of species that feed on fruits, coupled with their wide dispersal ability through flight. We evaluated the bat-plant interaction network structure in forest areas of the Amazon, Cerrado, and the ecotonal region between these biomes. Using ecological network theory, we examined the contribution of species in structuring these networks and the main predictors of the roles bat species play. We captured bats in the field and collected seeds from fecal samples to identify plant species consumed in three landscape-scale environments. We built interaction networks for each environment, and evaluated the number of links, specialization, and modularity of each network. We also calculated species-level metrics to assess the contribution of bat and plant species to structuring the interaction networks. Finally, we tested the influence of bat mass, degree of frugivory, and abundance on their role in the networks. We identified 348 interactions and 177 links in the three networks, recording 21 bat species and 77 plant species. We found a higher number of links in the ecotone network, which is also the most modular network. Carollia brevicauda and C. perspicillata had highest species strength and centrality values among bat species in the three interaction networks. Cecropia obstusa and Piper sp07 exhibited the highest species strength metric among plant species. Bat abundance was the best predictor of the role played by bats in the frugivory networks. The low specialization of the Amazon network may be due to the plant dominance of some species. However, the ecotone areas had the highest plant species richness, emphasizing the importance of this landscape in the context of environmental functionality and conservation in the ecotone. La frugivoría y la dispersión de semillas son procesos fundamentales para la biodiversidad, especialmente en ambientes forestales, cada vez más fragmentados y escasos. Los murciélagos son dispersores de semillas cruciales debido a la gran cantidad de especies que se alimentan de frutas, junto con su amplia capacidad de dispersión a través del vuelo. Evaluamos la estructura de la red de interacción murciélago-planta en áreas forestales del Amazonas, Cerrado y la región ecotonal entre estos biomas. Utilizando la teoría de redes ecológicas, examinamos la contribución de las especies en la estructuración de estas redes y los principales predictores del papel que desempeñan las especies de murciélagos. Capturamos murciélagos en el campo y recolectamos semillas de muestras fecales para identificar especies de plantas consumidas en tres ambientes a escala de paisaje. Construimos redes de interacción para cada entorno y evaluamos la cantidad de enlaces, especialización y modularidad de cada red. También calculamos métricas a nivel de especie para evaluar la contribución de las especies de murciélagos y plantas a la estructuración de las redes de interacción. Finalmente, probamos la influencia de la masa de los murciélagos, el grado de frugivoría y la abundancia en su papel en las redes. Identificamos 348 interacciones y 177 vínculos en las tres redes, registrando 21 especies de murciélagos y 77 especies de plantas. Encontramos un mayor número de enlaces en la red ecotone, que también es la red más modular. Carollia brevicauda y C. perspicillata tuvieron los valores más altos de fuerza y centralidad entre las especies de murciélagos en las tres redes de interacción. Cecropia obstusa y Piper sp07 exhibieron la métrica de fuerza de especie más alta entre las especies de plantas. La abundancia de murciélagos fue el mejor predictor del papel desempeñado por los murciélagos en las redes frugívoras. La baja especialización de la red amazónica puede deberse a la dominancia vegetal de algunas especies. Sin embargo, las áreas del ecotono tuvieron la mayor riqueza de especies vegetales, resaltando la importancia de este paisaje en el contexto de la funcionalidad y conservación ambiental en el ecotono. [ABSTRACT FROM AUTHOR]

One option for solving the scientific and applied problem of increasing the efficiency of finishing quartz crystal elements (QCEs) through controlling the structural, mechanical, and rheological characteristics of abrasive suspensions is presented. The finishing technology for manufacturing QCEs is flat finishing on machines using an abrasive suspension of fine Al2O3 particles. The dispersion medium in the abrasive suspension during finishing of QCEs ensures uniform distribution of abrasive grains over the lap, minimizes the sticking of separating quartz particles, and facilitates its dispersion. Control of the structural and mechanical characteristics of the abrasive suspension is achieved by introducing into the dispersion medium (water) stabilizers such as protective colloids, which prevent the approach of abrasive particles and the destruction of quartz. The problem of QCE finishing has been solved by the authors for the first time ever. [ABSTRACT FROM AUTHOR]

This study aimed to identify ascidians in the coastal area of Chabahar Bay and assess their biodiversity in three stations (University, Tiss, Lipar) and four seasons for the first time. Sampling was carried out in the intertidal zone from July 2019 to May 2020, and samples were counted using the quadrate method. After narcotizing (in menthol crystal solution) and fixing (in formaldehyde solution), ascidians were identified using identification keys. The assessment of ascidians in Chabahar Bay led to the identification of Phallusia nigra, Cnemidocarpa sp., and Styela plicata. Results showed that P. nigra had the highest density in Lipar station (6.01 ± 0.72 individuals m−2) and during winter (6.65 ± 0.87). On the other hand, Cnemidocarpa sp. had the highest density in the University station (6.93 ± 0.84) and during fall (6.03 ± 0.96). The dispersion index showed that all ascidians identified in Chabahar Bay had an aggregated dispersion pattern. Moreover, the sustainability index showed that P. nigra and Cnemidocarpa sp. are more sustainable than Styela plicata. Assessment of each species in various seasons and stations showed that their abundance fluctuates based on their biology and effective physical factors. On the other hand, the assessment of their biodiversity using usual biodiversity indices (Shannon-Weiner index, the Simpson index, and Margalef index) showed a significant effect (P < 0.05) of seasons and stations on these indices. The discernible impact of seasonal variations becomes more pronounced, underscoring the dynamic fluctuations in ascidian biodiversity within Chabahar Bay over the course of a year. [ABSTRACT FROM AUTHOR]

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation 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.)

Many foods are emulsions or dispersions containing lipids. The friction properties of foods are evaluated because they affect food texture and processability. Here, we evaluated the friction characteristics of 55 liquid or semisolid foods using a sinusoidal motion friction evaluation system to classify them based on friction dynamics. The contact surface was made to resemble a biological surface using agar gel, which exhibited a fractal structure, and the movement of the contact probe mimicked living movement by sinusoidal motion. The change in average friction coefficient (Δμ), static friction coefficient (Δμs) in a round trip, delay time (Δδ), and friction profile depended on the condition and rheological properties. Principal component analysis showed that all the friction parameters of Δμ, Δμs, Δδ, and the appearance ratio of the profile were involved in the principal components, Z1 and Z2 which are composite variables obtained by the contraction of many friction parameters in a principal component analysis. In addition, the foods were classified into three groups by cluster analysis using Z1 and Z2. The condition of the foods, rheological properties, and the presence or absence of lipids was the factors that defined each group. [ABSTRACT FROM AUTHOR]

Owing to the high fluid content, most incompressible soft structures typically exhibit viscosity, which has a significant influence on wave characteristics, especially attenuation. Meanwhile, they are inevitably prestressed owing to the volume-preserving deformations. Therefore, it is essential to investigate acoustoelastic and viscoelastic effects to better understand guided wave characteristics in a pre-stressed soft plate. To this end, a hyperviscoelastic model concerning viscoelasticity, acoustoelasticity, and nonlinearity is established to deduce the governed equations. An analytical integration orthogonal polynomial method is employed to solve complex solutions of wave equations. The dispersion, attenuation, and wave shapes are illustrated. The acoustoelastic and viscoelastic effects are analyzed. Some new wave phenomena are revealed: The pre-stretching inhibits wave attenuation, and the pre-compression promotes attenuation; As the pre-stress increases, high-frequency phase velocity and incremental displacement amplitudes increase. The results lay a theoretical foundation for guided wave elastography, quantitative characterization, and disease diagnosis of biological soft tissue. [ABSTRACT FROM AUTHOR]

Copyright of Critical Hermeneutics: Biannual Journal of Philosophy is the property of Universita degli Studi di Cagliari 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.)

Reliable reactive transport models require careful separation of mixing and dispersion processes. Here we treat displacing and displaced fluids as two separate fluid phases and invoke Whitman's classical two-film theory to model mass transfer between the two phases. We use experimental data from Gramling's bimolecular reaction experiment to assess model performance. Gramling's original model involved just three coupled PDEs. In this context, our new formulation leads to a set of seven coupled PDEs but only requires the specification of two extra parameters, associated with the mass transfer coefficient and its dependence on time. The two film mass transfer model provides a simple and theoretically based method for separating mixing from dispersion in Eulerian continuum-scale methods. The advantage of this approach over existing methods is that it enables the simulation of equilibrium chemical reactions without having to invoke unrealistically small reaction rate coefficients. The comparison with Gramling's experimental data confirms that our proposed method is suitable for simulating realistic and complicated bimolecular reaction behaviour. However, further work is needed to explore alternative methods for avoiding the need of a time-dependent mass transfer rate coefficient. [ABSTRACT FROM AUTHOR]

A mathematical model is developed to describe the conservative solute migration under sorption in a groundwater reservoir. For the complexity of the aquifer, it is assumed as heterogeneous and semi-infinite. Dispersion is considered as a varying power of seepage velocity. For the sake of real scenario of the aquifer, the seepage velocity, first-order decay (FOD), zero-order production (ZOP), and retardation factor are taken as spatio-temporal dependent parameters. Initially, the aquifer is assumed as polluted by a background source throughout the domain. Also, a temporally dependent pulse type sinusoidal input source is taken at origin of the aquifer. The other end of the aquifer is assumed as flux free. The retardation factor considered with a special form due to regional and complication of the porous medium. The transient velocity is considered as sinusoidal, exponential, algebraic sigmoid and asymptotic forms to study the solute transport behavior under different velocity patterns. The analytical solution of the proposed model is obtained by Laplace and inverse Laplace transform techniques. All the graphical plots are obtained by MATLAB software. The present study may be helpful for scientists, geologists to determine the time and position of harmless concentration level and can be treated as preliminary tool for solute migration for the future researchers. [ABSTRACT FROM AUTHOR]

A functional hybrid nano-hydroxyapatite (carboxymethyl cellulose-phytic acid-n-HA, CMC-PA-n-HA) was prepared by adding CMC and PA. The results of Fourier transformation infrared spectra, X-ray diffraction, thermal gravimetric analysis and dispersion experiments indicated that the addition of CMC and PA affected the morphology, crystallinity and crystal size of hybrid n-HA, and CMC endowed hybrid n-HA with excellent dispersion. Scanning electron microscope results showed that CMC-PA-n-HA nanoparticle could be uniformly dispersed in chitosan (CS) matrix to obtain composite membrane by casting technology, so that the highest tensile strength of CMC-PA-n-HA/CS composite membrane was 69.64% and 144.45% higher than that of CS membrane and n-HA/CS composite membrane, respectively. Contact angle test showed that CMC-PA-n-HA effectively improved hydrophilicity of the CS membrane. The simulated body fluid immersion results indicated that the CMC-PA-n-HA/CS composite membrane not only exhibited good degradability but also promoted bone-like apatite deposition. The cell proliferation experiments proved that the introduction of PA made the composite membrane have better cell adhesion and proliferation ability. Antibacterial tests demonstrated that PA could effectively improve the antibacterial properties of the composite membrane, which is expected to be applied as guide bone tissue regeneration membrane. [ABSTRACT FROM AUTHOR]

A novel type of polarization negative curvature terahertz fiber has been designed, which has a cladding region composed of two long semi-circular cladding tubes in the horizontal direction and four long semi-elliptical cladding tubes in the oblique direction. The optimal fiber dimensions are determined to investigate the internal relationship between polarization characteristics and fiber cladding structure. The transmission performances of the negative curvature fiber are investigated by varying the thickness of fiber cladding tubes and adjusting the structural characteristics of cladding tubes in different directions. Relatively good transmission performances can be obtained with a cladding tube thickness of 80 μ m. The birefringence can be stably maintained at the order of 10−4, and the confinement loss of the x -polarized mode at 2.55 THz is 0.036 dB cm−1. Moreover, the dispersion coefficient of the two polarized modes is stable between ±0.6 ps (THz·cm)−1 in the 2.3–2.6 THz band. The bent performance of the designed fiber at 2.52 THz is also discussed. The results show that the fiber has low bending sensitivity, and can still maintain excellent birefringence and low confinement loss in the bending state. For the y polarization, the birefringence can be basically stabilized at the order of 10−4 within a bending radius of 10–60 cm. [ABSTRACT FROM AUTHOR]

Abstract This study provides the first report of metazoan parasites in Crenicichla strigata. From 31 hosts caught in the Jari River basin, in the eastern Amazon region of Brazil, a total of 1454 parasites were collected: Sciadicleithrum araguariensis, Sciadicleithrum joanae, Sciadicleithrum satanopercae, Posthodiplostomum sp., Genarchella genarchella, Contracaecum sp., Spirocamallanus peraccuratus, Acarina gen. sp. and Dolops geayi. However, the community was dominated by the three species of Sciadicleithrum (Monogenea) and there was similar presence of parasites in the larval and adult stages. The total prevalence was 100% and each of the hosts was parasitized by two or three species, which presented random dispersion. Brillouin diversity, parasite species richness, Berger-Parker dominance index and evenness were low. There was positive correlation between the abundance of Posthodiplostomum sp. the hosts’ length, while the abundance of S. peraccuratus showed negative correlation with the body weight of fish. The abundance of S. araguariensis, S. joanae and S. satanopercae showed negative correlation with the hosts’ length. The parasite community of C. strigata was characterized by low diversity, low richness, low intensity and low abundance of species.