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In this paper, the values of the absolute constants in the Kolmogorov–Rogozin and Kesten inequalities are refined for the concentration function of the sum of independent random vectors in a Hilbert space. [ABSTRACT FROM AUTHOR]

Experiments are routinely conducted to evaluate the toxicity of water effluents or chemicals. In a Ceriodaphnia dubia reproduction test, organisms are exposed to varying concentration levels of the toxicant or other adverse treatment and the number of young produced after a given experiment period are recorded. To analyze the test outcomes, mean reproduction is modeled as a function of the concentration, and the estimated concentrations associated with specified levels of adverse effect often are used in risk management. While aquatic toxicity analyses often focus on outcomes from the current test, laboratories commonly have a history of conducting such tests using the same species, following a similar experimental protocol. So it seems reasonable to assume that the same underlying biological process generates the historical and current tests. In the present study, we propose using a calibrated power prior approach to incorporate historical control outcomes as prior input, and compare the behavior of the method when different congruence measures are used to determine the amount of historical input that will be incorporated. Simulation results show that three of the congruence measures can improve precision and reduce bias of the potency estimates.Supplementary material to this paper is provided online. [ABSTRACT FROM AUTHOR]

In part I of this paper series, the application of an incomplete adjoint operator to calculate the optimal reduction of the total emissions S′ was suggested. This paper, part II of the series, focuses on calculating the reduction of the anthropogenic emission source S′a As Sc (the source term due to the chemical reaction in the atmosphere) is a complex function of the pollutant concentration ρ, we propose an iterative optimization method using a positive-negative discriminant to obtain S′a from S′. The convergence of the iterations is also proven in this paper. [ABSTRACT FROM AUTHOR]

This paper aims to establish distribution-free concentration inequalities for the log-likelihood function of Bernoulli variables, which means that the tail bounds are independent of the parameters. Moreover, Bernstein's and Bennett's inequalities with optimal constants are obtained. The simulation study shows significant improvements over the previous results. [ABSTRACT FROM AUTHOR]

In this paper we study uniformly random lozenge tilings of strip domains. Under the assumption that the limiting arctic boundary has at most one cusp, we prove a nearly optimal concentration estimate for the tiling height functions and arctic boundaries on such domains: with overwhelming probability the tiling height function is within n δ of its limit shape, and the tiling arctic boundary is within n 1 / 3 + δ to its limit shape, for arbitrarily small δ > 0 . This concentration result will be used in Aggarwal and Huang (Edge statistics for lozenge tilings of polygons, II: Airy line ensemble, 2021. arXiv:2108.12874) to prove that the edge statistics of simply-connected polygonal domains, subject to a technical assumption on their limit shape, converge to the Airy line ensemble. [ABSTRACT FROM AUTHOR]

In aquatic toxicity tests, responses of interest from organisms exposed to varying concentration levels of the toxicant or other adverse treatment are recorded. These responses are modeled as functions of the concentration and the concentration associated with specified levels of estimated adverse effect are used in risk management. While aquatic toxicity analyses often focus on outcomes from a single experiment, laboratories commonly have a history of conducting such experiments using the same species, following a similar experimental protocol. So it is often reasonable to believe that the same underlying biological process generates the historical and current experiments. This connection may facilitate the design of more efficient experiments. In the present study, we propose a simulation-based Bayesian sample size determination approach using historical control outcomes as prior input and illustrate it using a C. dubia reproduction experiment with count outcomes. Simulation results show that precision of the potency estimates is improved via incorporation of historical data. For a standard EPA required test of 60 total organisms, when a single historical control study is incorporated assuming moderate relevance, the mean length (AL) of the 95 % interval of RI 25 (the concentration associated with 25 % inhibition relative to control) is reduced by 17 % . So more precision is possible from the historical control data or a reduction of 40 % of the 60 organism would result in the same precision for a pre-specified AL criterion. The incorporation of multiple historical controls assuming moderate relevance would reduce AL by 37 % , translating into a reduction of 70 % of the current default sample size. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Objectives: Research consistently shows that crime concentrates on a few repeatedly victimized places and targets. In this paper we examine whether the same is true for extortion against businesses. We then test whether the factors that explain the likelihood of becoming a victim of extortion also explain the number of incidents suffered by victimized businesses. The alternative is that extortion concentration is a function of event dependence. Methods: Drawing on Mexico's commercial victimization survey, we determine whether repeat victimization occurs by chance by comparing the observed distribution to that expected under a Poisson process. Next, we utilize a multilevel negative binomial-logit hurdle model to examine whether area- and business-level predictors of victimization are also associated with the number of repeat extortions suffered by businesses. Results: Findings suggest that extortion is highly concentrated, and that the predictors of repeated extortion differ from those that predict the likelihood of becoming a victim of extortion. While area-level variables showed a modest association with the likelihood of extortion victimization, they were not significant predictors of repeat incidents. Similarly, most business-level variables significantly associated with victimization risk showed insignificant (and sometimes contrary) associations with victimization concentration. Overall, unexplained differences in extortion concentration at the business-level were unaffected by predictors of extortion prevalence. Conclusions: The inconsistent associations of predictors across the hurdle components suggest that extortion prevalence and concentration are fueled by two distinct processes, an interpretation congruent with theoretical expectations regarding extortion that considers that repeats are likely fueled by a process of event dependence. [ABSTRACT FROM AUTHOR]

Zinc (Zn) and its alloys have received increasing attention as new alternative biodegradable metals. However, consensus has not been reached on the corrosion behaviour of Zn. As cardiovascular artery stent material, Zn is supposed to contact with plasma that contains inorganic salts and organic components. Protein is one of the most important constitute in the plasma and could adsorb on the material surface. In this paper, bovine serum albumin (BSA) was used as a typical protein. Influences of BSA on pure Zn corrosion in phosphate buffered saline is investigated as a function of BSA concentrations and immersion durations by electrochemical techniques and surface analysis. Results showed that pure Zn corrosion was progressively accelerated with BSA concentrations (ranging from 0.05 to 5 g L−1) at 0.5 h. With time evolves, formation of phosphates as corrosion product was delayed by BSA adsorption, especially at concentration of 2 g L−1. Within 48 h, the corrosion of pure Zn was alleviated by BSA at concentration of 0.1 g L−1, whereas the corrosion was enhanced after 168 h. Addition of 2 g L−1 BSA has opposite influence on the pure Zn corrosion. Furthermore, schematic corrosion behaviour at protein/Zn interfaces was proposed. This work encourages us to think more about the influence of protein on the material corrosion and helps us to better understand the corrosion behaviour of pure Zn. [ABSTRACT FROM AUTHOR]

Let X,X, . . . , X be independent, identically distributed random variables. In this paper, we study the behavior of concentration functions of the weighted sums $$ {\displaystyle \sum_{k=1}^n{a}_k{X}_k} $$ with respect to the arithmetic structure of coefficients a. Such concentration results recently became important in connection with the study of singular values of random matrices. In this paper, we formulate and prove some refinements of a result of Vershynin (2014). [ABSTRACT FROM AUTHOR]

In this paper, we introduce a new concept of approximate optimal stepsize for gradient method, use it to interpret the Barzilai-Borwein (BB) method, and present an efficient gradient method with approximate optimal stepsize for large unconstrained optimization. If the objective function f is not close to a quadratic on a line segment between the current iterate xk and the latest iterate xk−1, we construct a conic model to generate the approximate optimal stepsize for gradient method if the conic model is suitable to be used. Otherwise, we construct a new quadratic model or two other new approximation models to generate the approximate optimal stepsize for gradient method. We analyze the convergence of the proposed method under some suitable conditions. Numerical results show the proposed method is very promising. [ABSTRACT FROM AUTHOR]

Wet anisotropic etching is extensively employed in silicon bulk micromachining to fabricate microstructures for various applications in the field of microelectromechanical systems (MEMS). In addition, it is most widely used for surface texturing to minimize the reflectance of light to improve the efficiency of crystalline silicon solar cells. In wet bulk micromachining, the etch rate is a major factor that affects the throughput. Slower etch rate increases the fabrication time and therefore is of great concern in MEMS industry where wet anisotropic etching is employed to perform the silicon bulk micromachining, especially to fabricate deep cavities and freestanding microstructures by removal of underneath material through undercutting process. Several methods have been proposed to increase the etch rate of silicon in wet anisotropic etchants either by physical means (e.g. agitation, microwave irradiation) or chemically by incorporation of additives. The ultrasonic agitation during etching and microwave irradiation on the etchants increase the etch rate. However, ultrasonic method may rupture the fragile structures and microwave irradiation causes irradiation damage to the structures. Another method is to increase the etching temperature towards the boiling point of the etchant. The etching characteristics of pure potassium hydroxide solution (KOH) is studied near the boiling point of KOH, while surfactant added tetramethylammonium hydroxide (TMAH) is investigated at higher temperature to increase the etch rate. Both these studies have shown a potential way of increasing the etch rate by elevating the temperature of the etchants to its boiling point, which is a function of concentration of etch solution. The effect of various kinds of additives on the etch rate of silicon is investigated in TMAH and KOH. In this paper, the additives which improve the etch rate have been discussed. Recently the effect of hydroxylamine (NH2OH) on the etching characteristics of TMAH and KOH is investigated in detail. The concentration of NH2OH in TMAH/KOH is varied to optimize the etchant composition to obtain improved etching characteristics especially the etch rate and undercutting which are important parameters for increasing throughput. In this article, different methods explored to improve the etch rate of silicon have been discussed so that the researchers/scientists/engineers can get the details of these methods in a single reference. [ABSTRACT FROM AUTHOR]

Cold sintering of ZnO using crystalline zinc acetate dihydrate in the absence of added water is examined. Prior studies use an aqueous solvent, usually containing a weak acid, base, or organic salt, as the mass transport phase during cold sintering. This paper shows equivalent densification of ZnO using solid, powdered acetate as compared to previously mentioned aqueous-based transport phases. It also presents the potential to add zinc acetate in higher quantities without increasing the amount of total added transport phase, as solubility limits in aqueous solvents define the maximum amount of zinc acetate that can be added for a given volume of liquid. Experiments were conducted using the previously reported sinterometer, allowing for in situ experimental monitoring to show densification trends of this new transport phase as a function of concentration, time, and temperature. The potentially dramatic impacts of varying humidity during powder preparation on final sample density will also be discussed. [ABSTRACT FROM AUTHOR]

The paper deals with studying a connection between the Littlewood-Offord problem and estimating the concentration functions of some symmetric infinitely divisible distributions. Some multivariate generalizations of Arak's results (1980) are given. They establish a relationship of the concentration function of the sum and arithmetic structure of supports of the distributions of independent random vectors for arbitrary distributions of summands. Bibliography: 21 titles. [ABSTRACT FROM AUTHOR]

In this paper, we propose a hybrid CQ projection algorithm with two projection steps and one Armijo-type line-search step for the split feasibility problem. The line-search technique is intended to construct a hyperplane that strictly separates the current point from the solution set. The next iteration is obtained by the projection of the initial point on a regress region (the intersection of three sets). Hence, algorithm converges faster than some other algorithms. Under some mild conditions, we show the convergence. Preliminary numerical experiments show that our algorithm is efficient. [ABSTRACT FROM AUTHOR]

In this paper we study the behavior of concentration functions of weighted sums of independent random variables with respect to the arithmetic structure of coefficients. Recently, Tao and Vu formulated a so-called Inverse Principle in the Littlewood-Offord problem. We discuss the relations between this Inverse Principle and a similar principle formulated for sums of arbitrarily distributed independent random variables formulated by T. Arak in the 1980's. [ABSTRACT FROM AUTHOR]

In this paper, we formulate and prove multidimensional generalizations of results obtained previously by the author and A. Yu. Zaitsev. Let X, X , . . . , X be independent, identically distributed random variables. We study the behavior of the concentration function of the random variable $$ {\displaystyle \sum_{k=1}^n{X}_k{a}_k} $$ according to the arithmetic structure of the vectors a. Recently, interest to this problem increased significantly due to study of distributions of eigenvalues of random matrices. In this paper, we formulate and prove some refinements of results of Rudelson-Vershinin and Friedland-Sodin. Bibliography: 29 titles. [ABSTRACT FROM AUTHOR]

In this paper, the effects of a polarization-modulated quaternary AlInGaN quantum barrier on carrier capture capability and the overlap rate of wave functions in deep-ultraviolet light-emitting diodes (DUV-LEDs) are numerically investigated. By controlling the band bending degree by adjusting polarization intensity (ΔP) in the active region, the band bending is alleviated, and electrons and holes move from both sides of the quantum well to the center, which increases the overlap rate of wave functions and enhances the light output power of DUV-LEDs. Also, there is a limitation on improving the performance of DUV-LEDs by reducing the polarization intensity. This is because the reduced polarization intensity (ΔP) flattens the energy band, reduces the two-dimensional electron gas (2DEG) concentration at the quantum well/quantum barrier (QW/QB) interface, and decreases the effective barrier height. The lower effective barrier height reduces the capability of carrier confinement and carrier concentration in the active region, resulting in the imbalance between the wave function and the carrier concentration, which limits further enhancement of the performance of DUV-LEDs. [ABSTRACT FROM AUTHOR]

The seeds and leaves of Cupressus sempervirens essential oils were evaluated against the khapra beetle, Trogoderma granarium at different concentrations. Mortality, repellence activity, adult emergence rate, larvae chemical profile (protein contents and energy reserves), seed germination effect, and grain damage were assessed. The results of phytochemical screening of C. sempervirens leaf and seed demonstrated the presence of saponins, flavonoids, leucoanthocyanins, catechetical tannins, and gallic tannins. We identified eighty-two (82) compounds for leaves and seventy-four (74) for seeds by GC/MS. The major compounds for leaf and seed EOs were α-pinene (33.65% and 26.53%), δ-3-Carene (14.78% and 19.48%) and terpinolene (4.25% and 4.13%), respectively. C. sempervirens exhibited fumigant toxicity and repellent activity as a function the concentrations. C. sempervirens leaves was most potent both in adult emergence (66.94%) and germination rate (99%) compared to seeds oil. Furthermore, the seed and leaf oils significantly reduced seed damage. Finally, the treatments induced an alteration of the biochemical profile via a decrease in energy reserves and protein content. The data obtained suggest that the toxicity of EO by fumigation could be explained by an alteration of insect metabolism via food uptake and digestion. [ABSTRACT FROM AUTHOR]

The aim of the present work is evaluation of absolute constants in the Arak inequalities for the concentration functions of convolutions of probability distributions. This result allows us to calculate the constant in the inequality for the uniform distance between n and (n + 1)-fold convolutions of one-dimensional symmetric probability distributions with a characteristic function separated from −1, as well as a number of other estimates, in particular, the accuracy of approximation of samples of rare events by the Poisson point process. [ABSTRACT FROM AUTHOR]

In recentwork, the local convergence behavior of path-following interior-point methods and sequential quadratic programming methods for nonlinear programming has been investigated for the case in which the assumption of linear independence of the active constraint gradients at the solution is replaced by the weaker Mangasarian-Fromovitz constraint qualification. In this paper, we describe a stabilization of the primal-dual interior-point approach that ensures rapid local convergence under these conditions without enforcing the usual centrality condition associated with path-following methods. The stabilization takes the form of perturbations to the coefficient matrix in the step equations that vanish as the iterates converge to the solution. [ABSTRACT FROM AUTHOR]

Agents for uranium stripping from a 30% solution of TBP in decane, loaded with 110–116 g/L uranium, were studied. The uranyl nitrate solubility in ammonium acetate and formate solutions was studied. The uranium distribution ratio as a function of the concentrations of ammonium acetate and formate was determined. Comparative trials of the suggested stripping agents were performed. Ammonium acetate and formate were shown to be suitable for uranium stripping. [ABSTRACT FROM AUTHOR]

In order to study the strength reliability of interconnections, a generalized model for quantifying the effect of nonequilibrium point crystal defects on the value of the work of the reversible separation of joined materials along the boundary (interface) of their union, generalizing an approach proposed previously by the authors to the description of the mechanism of defect adsorption in the interface area. The developed model makes it possible not to be limited to the situation when the defects of each of the contacting materials are distributed independently in the boundary, over their sublattices, and the transitions of defects between these sublattices are also taken into account, that significantly expands the possibilities of applying the obtained theoretical results. The corresponding system of equations is formulated, that makes it possible to find and study the value of the work of reversible separation as a function of defect concentrations in the bulks of materials. In the case when the interstitial impurity atoms are the defects, the problem of the critical impurity concentrations at which the work of reversible separation vanishes and the bonding of the materials becomes thermodynamically unstable is studied in detail by analytical methods; the role of defect transitions between the sublattices, in which defects are localized at the interface, is explained. Impurity concentrations are estimated at which the effect of the interface instability can be realized, significantly affecting the reliability characteristics of the interconnections. [ABSTRACT FROM AUTHOR]

In the present study, the investigation of the levels of the local and regional oxidants concentration at Athens, Greece, is attempted by analyzing the observations obtained at an urban and a rural station, during 2001-2011 and 2007-2011, respectively. A progressive increase of the daytime and nighttime average of [NO]/[O] versus [NO] is observed showing a larger proportion of O in the form of NO when the level of NO increases. Similar results are observed when studying the variation of mean values of [NO]/[NO] versus [NO]. The results obtained when compared with those that have earlier detected elsewhere, revealed similarities and discrepancies that are discussed in detail. The parameterized curves that are presented for the first time in this paper may be used by the air quality planners to track the trends in other cities also, and to understand what is or was driving them. [ABSTRACT FROM AUTHOR]

This paper is concerned with density estimation based on the stagewise minimization of the U-divergence. The U-divergence is a general divergence measure involving a convex function U which includes the Kullback-Leibler divergence and the L norm as special cases. The algorithm to yield the density estimator is closely related to the boosting algorithm and it is shown that the usual kernel density estimator can also be seen as a special case of the proposed estimator. Non-asymptotic error bounds of the proposed estimators are developed and numerical experiments show that the proposed estimators often perform better than several existing methods for density estimation. [ABSTRACT FROM AUTHOR]

In this paper we investigate the problem of extracting information about chemical reactions involving multiple species from the time history of the concentration of each species. The mathematical model of the kinetic system leads to a system of ordinary differential equations. Our focus is to examine whether the species' concentrations as functions of time are sufficient to determine what chemical reactions, and at what reaction rates, have occurred. We show that within the limitation of our model, there may be many candidate reaction systems that could explain the data. Using the notion of sparsity, we provide a quantitative assessment of the question of distinguishability. We further demonstrate that sparsity enforcing approaches, such as minimizing the ℓ or the ℓ norms are not reliable. Our conclusion is that additional knowledge about the kinetic system will be necessary to reliably solve this inverse problem. [ABSTRACT FROM AUTHOR]

The analytical expression of the concentration of the species, in the electrochemical cell, with tubular electrode and optical fibres inserted into it, from its two ends is derived using the finite Hankel transformation. A series form of an analytical expression for current and absorbance responses of the spectroelec-trochemical cell has been derived. The analytical expressions of current and absorbance in terms of parameters K, K, ε and ε for chronoamperometry are given. Available numerical results are compared with our analytical results and are found to be in good agreement. [ABSTRACT FROM AUTHOR]

This paper presents a new approach based on extrapolation to accelerate the linear convergence process of Vectorized Moore-Skelboe (VMS) algorithm. The VMS is a modified version of basic Moore-Skelboe (MS) algorithm, where the vectorization is used as a means to speed up the basic MS algorithm. We propose to further accelerate the converging process of VMS from linear to quadratic by combining the Richardson extrapolation technique with VMS. The effectiveness of the proposed algorithm is tested on various multivariate examples and compared with the unaccelerated conventional method, i.e., MS and well-known optimization software GlobSol. The test results show that the proposed extrapolation-based VMS offer considerable speed improvements over both the existing algorithms. [ABSTRACT FROM AUTHOR]

This paper analyzes the equilibria between immunoglobulins ( R), homo-bifunctional ligands ( L), monovalent ligands ( I), and their complexes. We present a mathematical model that can be used to estimate the concentration of each species present in a mixture of R, L, and I, given the initial conditions defining the total concentration of R, L, I, and four dissociation constants ( $$ K_{\rm{d}}^{\rm{inter}} $$, $$ K_{\rm{d}}^{\rm{intra}} $$, $$ K_{\rm{d}}^{\rm{mono}} $$, and α). This model is based on fewer assumptions than previous models and can be used to describe exactly a broad range of experimental conditions. A series of curves illustrates the dependence of the equilibria upon the total concentrations of receptors and ligands, and the dissociation constants. We provide a set of guidelines for the design and analysis of experiments with a focus on estimating the binding constants from experimental binding isotherms. Two analytical equations relate the conditions for maximum aggregation in this system to the binding constants. This model is a tool to quantify the binding of immunoglobulins to antigens and a guide to understanding and predicting the experimental data of assays and techniques that employ immunoglobulins. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Purpose: Todorokite is one common manganese oxide in soils and sediments and is commonly formed from layered Na-buserite. Aging processes can alter the physicochemical properties of freshly formed Na-buserite in natural environments. However, it is not clear whether and how aging affects the formation of todorokites. In the present paper, Na-buserite with aging treatment was employed to prepare todorokite at atmospheric pressure to investigate the effects of aging treatment of Na-buserite on the formation of todorokite. Materials and methods: Four aged Na-buserite samples, which are produced through oxidation of Mn in concentrated NaOH medium by O with aging for 3, 6, 9, and 12 months, were employed to investigate the effects of aging processes on the transformation from Na-buserite to todorokite by Mg-templating reaction at atmospheric pressure. The manganese oxides were examined using X-ray diffraction (XRD), elemental analysis, determinations of the average manganese oxidation number, infrared spectroscopy (IR), and transmission electron microscopy (TEM). Results and discussion: The XRD, IR, and elemental analyses indicate that aging treatment can alter the substructure of the freshly synthesized Na-buserite. During the aging process, some of the Mn(III) may migrate into the interlayer region or disproportionate to form Mn and Mn from the layer of Na-buserite and the concomitant formation of layer vacancies. The interlayer Mn or Mn occupied above or below the layer vacancy sites and become corner-sharing octahedral. XRD analyses and TEM clearly show that the transformation from Na-buserite to todorokite was promoted by aging treatments. The alterations of substructure of aged Na-buserites can promote the rearrangement of manganese to construct a tunnel structure during the transformation from layered manganese oxides to tunnel-structure todorokite at atmospheric pressure. Conclusions: The transformation from Na-buserite to todorokite was promoted by aging treatments at atmospheric pressure, and it is more suitable to explore the origination of natural todorokite in Earth surface environments using aged layered manganese oxides. [ABSTRACT FROM AUTHOR]

In this paper, we propose a level set method for shape-driven object extraction. We introduce a voxel-wise probabilistic level set formulation to account for prior knowledge. To this end, objects are represented in an implicit form. Constraints on the segmentation process are imposed by seeking a projection to the image plane of the prior model modulo a similarity transformation. The optimization of a statistical metric between the evolving contour and the model leads to motion equations that evolve the contour toward the desired image properties while recovering the pose of the object in the new image. Upon convergence, a solution that is similarity invariant with respect to the model and the corresponding transformation are recovered. Promising experimental results demonstrate the potential of such an approach. [ABSTRACT FROM AUTHOR]

The original 3-D brick Cosserat point element (CPE) satisfies a nonlinear form of the patch test for general element shapes but the coefficients in the strain energy function for inhomogeneous deformations were motivated by considering solutions for a rectangular parallelepiped. In this paper, a generalized functional form for the strain energy of inhomogeneous deformations is proposed for irregular shaped elements. The coefficients in this strain energy function are determined by matching exact pure bending solutions for three right cylindrical parallelepipeds with their cylindrical axes oriented along three orthogonal base vectors. A generalization is proposed which ensures that this strain energy function remains positive definite for general irregular shaped elements. A number of example problems are considered which show that the performance of this improved CPE is good for irregular shaped elements. Moreover, the improved CPE continues to predict physical results for nonlinear and buckling problems that typically cause lack of convergence with other element formulations due to unphysical hourglassing. [ABSTRACT FROM AUTHOR]

In this paper, we consider a three dimensional Ginzburg–Landau type equation with a periodic initial value condition. A fully discrete Galerkin–Fourier spectral approximation scheme is constructed, and then the dynamical properties of the discrete system are analyzed. First, the existence and convergence of global attractors of the discrete system are proved by a priori estimates and error estimates of the discrete solution, and the numerical stability and convergence of the discrete scheme are proved. Furthermore, the long-time convergence and stability of the discrete scheme are proved. [ABSTRACT FROM AUTHOR]

Fluctuating plume models provide a useful conceptual paradigm in the understanding of plume dispersion in a turbulent flow. In particular, these models have enabled analytical predictions of higher-order concentration moments, and the form of the one-point concentration probability density function (PDF). In this paper, we extend the traditional formalism of these models, grounded in the theory of homogeneous and isotropic turbulent flow, to two cases: namely, a simple sheared boundary layer and a large array of regular obstacles. Some very high-resolution measurements of plume dispersion in a water channel, obtained using laser-induced fluorescence (LIF) line-scan techniques are utilised. These data enable us to extract time series of plume centroid position (plume meander) and dispersion in the relative frame of reference in unprecedented detail. Consequently, experimentally extracted PDFs are able to be directly compared with various theoretical forms proposed in the literature. This includes the PDF of plume centroid motion, the PDF of concentration in the relative frame, and a variety of concentration moments in the absolute and relative frames of reference. The analysis confirms the accuracy of some previously proposed functional forms of model components used in fluctuating plume models, as well as suggesting some new forms necessary to deal with the complex boundary conditions in the spatial domain. [ABSTRACT FROM AUTHOR]

The expected mass fraction (EMF) is used to quantify concentration values in a contaminant cloud. Low-ordered moments of the probability density function (PDF) of concentration are integrated and inverted to approximate the EMF. A simple prescription for the distributed moments of the PDF is shown to be related to a set of relationships between normalized moments. These relationships appear to be very robust and approximately universal across measured values from laboratory clouds and plumes in the atmospheric boundary layer over different stability classes. Also, these relationships have the important advantage that they can be validated from isolated fixed-point measurements. In this paper, we verify our results with data from a plume in grid turbulence. The EMF for these experiments is shown to be well approximated by a simple Beta function. [ABSTRACT FROM AUTHOR]

We consider a convexification method for a class of nonsmooth monotone functions. Specifically, we prove that a semismooth monotone function can be converted into a convex function via certain convexification transformations. The results derived in this paper lay a theoretical base to extend the reach of convexification methods in monotone optimization to nonsmooth situations. [ABSTRACT FROM AUTHOR]

By integrating the cooperative approach with the fast annealing coevolutionary algorithm (FAEA), a so-called cooperative fast annealing coevolutionary algorithm (CFACA) is presented in this paper for the purpose of solving high-dimensional problems. After the partition of the search space in CFACA, each smaller one is then searched by a separate FAEA. The fitness function is evaluated by combining sub-solutions found by each of the FAEAs. It demonstrates that the CFACA outperforms the FAEA in the domain of function optimization, especially in terms of convergence rate. The current algorithm is also applied to a real optimization problem of protein motif extraction. And a satisfactory result has been obtained with the accuracy of prediction achieving 67.0%, which is in agreement with the result in the PROSITE database. [ABSTRACT FROM AUTHOR]

In this paper, we present a new trust region method for nonlinear equations with the trust region converging to zero. The new method preserves the global convergence of the traditional trust region methods in which the trust region radius will be larger than a positive constant. We study the convergence rate of the new method under the local error bound condition which is weaker than the nonsingularity. An example given by Y.X. Yuan shows that the convergence rate can not be quadratic. Finally, some numerical results are given. [ABSTRACT FROM AUTHOR]

Suppose that g(n) is an additive real-valued function, W(N) = 4+min λ(λ² + ∑p 1/p min(1, (g(p) - λ log p)²)), E(N) = 4 + ∑p 1/p. In this paper, we prove the existence of constants C1, C2 such that the following inequalities hold: supa¦[n,m,k:m,k ∈ Z, n ∈ N, n + m²+ k² = N, g(n) ∈ [a,a+1)]¦ ≤ C1N / √W(N), supa¦[n,m,k:m,k ∈ Z, n ∈ N, n + m²+ k² = N, g(n) = a]¦ ≤ C2N / √E(N). The obtained estimates are order-sharp. [ABSTRACT FROM AUTHOR]

Suppose that $g(n)$ is a real-valued additive function and $\backslash tau(n)$ is the number of divisors of $n$. In this paper, we prove that there exists a constant $C$ such that

In this paper we study the problem of the approximation in law of the fractional Brownian sheet in the topology of the anisotropic Besov spaces. We prove the convergence in law of two families of processes to the fractional Brownian sheet: the first family is constructed from a Poisson procces in the plane and the second family is defined by the partial sums of two sequences of real independent fractional brownian motions. [ABSTRACT FROM AUTHOR]

The reciprocal theorem was applied to solve the bending of the rectangular plates with each edges arbitrary a point supported under a concentrated load, the exact solutions and computation example are given. [ABSTRACT FROM AUTHOR]

Natural wine fermentation depends on a complex consortium of native microorganisms rather than inoculation of industrial yeast strains. While this diversity of yeasts can result in an increased repertoire of wine flavors and aromas, it can also result in the inhibition of Saccharomyces cerevisiae, which is uniquely able to complete fermentation. Understanding how yeast species interact with each other within the wine-fermenting community and disentangling ecological interactions from environmental impacts on growth rates, is key to developing synthetic communities that can provide the sensory benefits of natural fermentation while lowering the risk of stuck ferments. Here, we co-culture all pairwise combinations of five commonly isolated wine-fermenting yeasts and show that competitive outcomes are a strong function of ethanol concentration, with frequency-dependent bistable interactions common at low alcohol and an increasingly transitive competitive hierarchy developing as alcohol increases. We also show that pairwise outcomes are predictive of five-species community outcomes, and that frequency dependence in pairwise interactions propagates to alternative states in the full community, highlighting the importance of species abundance as well as composition. We also observe that monoculture growth rates are only weakly predictive of competitive success, highlighting the need to incorporate ecological interactions when designing synthetic fermenting communities. Co-culture of different combinations of five common wine-fermenting yeasts shows that competitive outcomes are a strong function of ethanol concentration, and highlights the need to incorporate ecological interactions when designing synthetic fermenting communities. [ABSTRACT FROM AUTHOR]

We have shown the possibility of mathematical analysis of complex biochemical reactions without simplifying assumptions regarding their parameters by investigating the mechanism of adenosine triphosphate (ATP) hydrolysis by the "basal" Mg2+-ATPase in which ATP (substrate), Mg2+ (essential activator) and MgATP (true substrate) compete for binding with the enzyme catalytic site. For this mechanism, we proved, using the quasi-steady state principle by Bodenstein, the existence and uniqueness of a quasi-steady state at any fixed parameters (initial reactant concentrations, positive reaction rate constants). On this basis, the definition of the initial reaction rate v as a function of the initial concentrations of ATP (x1), Mg2+ (x2), ATPase (x3) is given and the dependencies v vs. xi are investigated. We proved that at fixed initial concentrations of any two reactants, the kinetic curve v vs. xi has a unique maximum point. In different regions of the kinetic curve located before and after the maximum point, the initial rate may vary in different ways: in one region it can change more slowly than the reactant concentration, as in the case of hyperbolic dependencies, and in the other it can change much faster than the reactant concentration, as in the case of sigmoid dependencies, which is typical for regulatory enzymes. This initial rate behaviour causes the existence of four different types of bell-shaped kinetic curves. To quantify the degree of sigmoidity of kinetics, we used derivatives ∂ ln v ∂ ln x i which allowed us to estimate the maximal velocity of the initial rate change. [ABSTRACT FROM AUTHOR]

This work investigated the dissolution rate of flax fibers in the ionic liquid 1-ethyl-3-methylimidazolium acetate [C2mim] [OAc] with the addition of a cellulose anti-solvent, water. The dissolution process was studied as a function of time, temperature and water concentration. Optical microscopy is used to analyse the resultant partially dissolved fibers. Distilled water was added to the solvent bath at the concentrations of 1%, 2% and 4% by weight in order to understand its influence on the dissolution process. The effect of the addition of even small amounts of water was found to significantly decrease the speed of dissolution, decreasing exponentially as a function of water concentration. The resulting data of both pure (as received from the manufacturers) ionic liquid and ionic liquid/anti-solvent mixtures showed the growth of the coagulated fraction as a function of both dissolution time and temperature followed time temperature superposition. An Arrhenius behavior was found, enabling the measurement of the activation energy for the dissolution of flax fiber. The activation energy of the IL as received (0.2% water) was found to be 64 ± 5 kJ/mol. For 1%, 2% and 4% water systems, the activation energies were found to be 74 ± 7 kJ/mol, 97 ± 3 kJ/mol and 116 ± 0.6 kJ/mol respectively. Extrapolating these results to zero water concentration gave a value for the hypothetical dry IL (0% water) of 58 ± 4 kJ/mol. The hypothetical dry ionic liquid is predicted to dissolve cellulose 23% faster than the IL as received (0.2% water). [ABSTRACT FROM AUTHOR]

The current study offers a blend of volumetric and acoustic approaches to examine the interlinkage between homologous series of glycol molecules (ethylene glycol (EG), diethylene glycol (DEG) and triethylene glycol (TEG)) in aqueous gluconolactone mixtures. As a function of gluconolactone concentration (0.00, 0.01, 0.02 and 0.03) mol Kg− 1, the densities and sound velocity of taken ternary mixes of (water + gluconolactone + EG/DEG/TEG) were calculated at 288.15, 298.15, 308.15 and 318.15 K by means of Anton Paar DSA 5000 M. Utilizing the experimental values of density various volumetric properties such as apparent molar volume (V ϕ) , partial molar volume (V ϕ 0) , partial molar volume of transfer (Δ V ϕ 0) were calculated, and various acoustic parameters such as apparent molar isentropic compression (K ϕ , S) , partial molar isentropic compression (K ϕ , S 0) , partial molar isentropic compression of transfer (Δ K ϕ , S 0) was estimated. In addition to this the partial molar expansibility (E ϕ 0) , its first-order derivative ∂ E ϕ 0 / ∂ T P and pair-triplet interaction coefficients (VAB, KAB, VABB, KABB) were also found. The outcome is depicted in terms of mixture interactions and dominant interactions (solute–solvent) along with the estimation of structure-making/structure-breaking tendency of glycols in aqueous gluconolactone solutions. [ABSTRACT FROM AUTHOR]

Outer membrane proteins (OMPs) must exist as an unfolded ensemble while interacting with a chaperone network in the periplasm of Gram-negative bacteria. Here, we developed a method to model unfolded OMP (uOMP) conformational ensembles using the experimental properties of two well-studied OMPs. The overall sizes and shapes of the unfolded ensembles in the absence of a denaturant were experimentally defined by measuring the sedimentation coefficient as a function of urea concentration. We used these data to model a full range of unfolded conformations by parameterizing a targeted coarse-grained simulation protocol. The ensemble members were further refined by short molecular dynamics simulations to reflect proper torsion angles. The final conformational ensembles have polymer properties different from unfolded soluble and intrinsically disordered proteins and reveal inherent differences in the unfolded states that necessitate further investigation. Building these uOMP ensembles advances the understanding of OMP biogenesis and provides essential information for interpreting structures of uOMP-chaperone complexes. [ABSTRACT FROM AUTHOR]

There is a long tradition in the Biophysics community of using simulations as a means to understand macromolecular behavior in various physicochemical methods. This allows a rigorous means to interpret observations in terms of fundamental principles, including chemical equilibrium, reaction kinetics, transport processes and thermodynamics. Here we simulate data for the Gilbert Theory for self-association, a fundamental analytical ultracentrifuge (AUC) technique to understand the shape of sedimentation velocity reaction boundaries that involve reversible monomer–Nmer interactions. Simulating monomer–dimer through monomer–hexamer systems as a function of concentration about the equilibrium constant allows a visual means to differentiate reaction stoichiometry by determining end points and inflection positions. Including intermediates (eg A1-A2-A3-A4-A5-A6) in the simulations reveals the smoothing of the reaction boundary and the removal of sharp inflections between monomers and polymers. The addition of cooperativity restores sharp boundaries or peaks to the observation and allows more discrimination in the selection of possible fitting models. Thermodynamic nonideality adds additional features when applied across wide ranges of concentration that might be appropriate for high-concentration therapeutic monoclonal antibody (mAb) solutions. This presentation serves as a tutorial for using modern AUC analysis software like SEDANAL for selecting potential fitting models. [ABSTRACT FROM AUTHOR]

Relativistic hydrodynamics of classic plasmas is derived from the microscopic model in the limit of ideal plasmas, while the microscopic description assumes the level of dynamics of individual particles and the kinetic models look as the macroscopic models in this approach. The chain of equations is constructed step by step starting from the concentration evolution. It happens that the energy density and the momentum density do not appear at such approach, but new relativistic hydrodynamic variables appear in the model. These variables has no nonrelativistic analogs, but they are reduced to the concentration, the particle current, the pressure (the flux of the particle current) if relativistic effects are dropped. These variables are reduced to functions of the concentration, the particle current, the pressure if the thermal velocities are dropped in compare with the relativistic velocity field. Final equations are presented in the monopole limit of the mean-field (the self-consistent field) approximation. Hence, the contributions of the electric dipole moment, magnetic dipole moment, electric quadrupole moment, etc., of the macroscopically infinitesimal element of volume appearing in derived equations are dropped. [ABSTRACT FROM AUTHOR]

Boric acid is a significant radioactive waste generated during the operation of nuclear power plants. Cementitious materials have been widely studied for the immobilization of boric acid. The generally used natural boric acid has been replaced by enriched boric acid for geochemical reasons and are expected to have varied behaviors in cementitious matrices. Results showed that simulated enriched/natural boric acid liquid wastes mostly contain boron in B (OH) 4 - and B 5 O 6 (OH) 4 - ionic forms, but the mass ratio of these species is higher in enriched boric acid solutions. In function with the concentration of enriched/natural boric acid, the solidified cementitious materials show different mineralogy. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) experiments utilizing parahydrogen-induced polarization (PHIP) were performed to elucidate the PHIP activity of the synthetic 236 kDa biopolymer poly-γ-(4-propargyloxy)-benzyl-L-glutamate) (PPOBLG). The homopolypeptide was successfully hyperpolarized and the enhanced signals were detected in 11.7 T solution NMR as a function of the PPOBLG concentration. The hydrogenation with parahydrogen caused signal enhancements of 800 and more for the vinyl protons of the side chain at low substrate concentration. As a result of this high enhancement factor, even at 13 nM of PPOBLG, a single scan 1H-NMR detection of the hyperpolarized protons was possible, owing to the combination of hyperpolarization and density of PHIP active sites. [ABSTRACT FROM AUTHOR]