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Batch verification for digital signature scheme is a method to verify multiple signatures simultaneously. The complex exponent test (CE test for short) proposed by Cheon and Lee is one of the most efficient batch verification tests for several digital signature schemes on certain types of elliptic curves (including Koblitz curves). The security of the CE test relies essentially on the cardinality of a subset of a residue ring of the endomorphism ring of an elliptic curve over an ideal. They have evaluated the cardinality of the above subset, and have illustrated the effectiveness of the CE test by using the evaluation. The aim of this paper is to point out that their evaluation contains a flaw. The flaw is generally related to two roots of a quadratic equation which is used in their argument. We mend the flaw of their evaluation. Our correct evaluation shows that the CE test can achieve the same security as the underlying signature scheme on Koblitz curves. As a result, the CE test is a secure batch verification when the underlying signature scheme uses Koblitz curves.

We consider the convergence rate of the alternating projection method for the nontransversal intersection of a semialgebraic set and a linear subspace. For such an intersection, the convergence rate is known as sublinear in the worst case. We study the exact convergence rate for a given semialgebraic set and an initial point, and investigate when the convergence rate is linear or sublinear. As a consequence, we show that the exact rates are expressed by multiplicities of the defining polynomials of the semialgebraic set, or related power series in the case that the linear subspace is a line, and we also decide the convergence rate for given data by using elimination theory. Our methods are also applied to give upper bounds for the case that the linear subspace has the dimension more than one. The upper bounds are shown to be tight by obtaining exact convergence rates for a specific semialgebraic set, which depend on the initial points., 22 pages, 1 figure

We study a class of nonlinear evolution systems of time fractional partial differential equations using Lie symmetry analysis. We obtain not only infinitesimal symmetries but also a complete group classification and a classification of group invariant solutions of this class of systems. We find that the class of systems of differential equations studied is naturally divided into two cases on the basis of the type of a function that they contain. In each case, the dimension of the Lie algebra generated by the infinitesimal symmetries is greater than 2, and for this reason we present the structures and one-dimensional optimal systems of these Lie algebras. The reduced systems corresponding to the optimal systems are also obtained. Explicit group invariant solutions are found for particular cases., Comment: 14 pages. To appear in Applied Mathematics and Computation

The claudin family comprises four-pass transmembrane proteins involved in the formation of tight junctions (TJs). Relatively recently, claudin domain containing (CLDND) 1, also known as claudin-25, was identified as a novel member of the claudin family. In the present study, we revealed that in the adult murine brain, CLDND1 is abundant in the cerebellum among common sites of intracerebral hemorrhage. Thus, the dynamics of CLDND1 after cerebellar hemorrhage were examined. Both CLDND1 mRNA and protein levels transiently decreased at 24 hr after hemorrhagic insult. For immunostaining, an anti-CLDND1 antibody that recognizes the specific epitope in the extracellular first loop was prepared. Dual immunohistochemical staining with CD31 using coronal cryosections of intact murine cerebellum tissue revealed that CLDND1 is expressed on endothelial cells. We therefore performed an in vitro permeability test using a human brain endothelial cell (HBEC) line to reveal whether CLDND1 contributes to cell adhesion like other claudins. CLDND1 was expressed on HBECs as well as in murine cerebellum tissue, and a strong signal was observed at TJs. RNA interference against CLDND1 decreased both the mRNA and protein levels without cytotoxicity. The permeability to small molecules, but not to large ones, across confluent HBECs increased on CLDND1 knockdown compared with mock-treated cells. These results suggest that the transient decrease of CLDND1 after cerebellar hemorrhage is responsible for low-molecular-weight selective vascular hyperpermeability. © 2017 Wiley Periodicals, Inc.

Zeta functions of periodic cubical lattices are explicitly derived by computing all the eigenvalues of the adjacency operators and their characteristic polynomials. We introduce cyclotomic-like polynomials to give factorization of the zeta function in terms of them and count the number of orbits of the Galois action associated with each cyclotomic-like polynomial to obtain its further factorization. We also give a necessary and sufficient condition for such a polynomial to be irreducible and discuss its irreducibility from this point of view., Comment: Advanced Studies in Pure Mathematics 84, 2020, Various Aspects of Multiple Zeta Functions, in honor of Professor Kohji Matsumoto's 60th birthday, pp. 93-121

Motivated by describing the symmetry of a theoretical model of dressed photons, we introduce several spaces with Lie group actions and the morphisms between them depending on three integer parameters n≥r≥s on dimensions. We discuss the symmetry on these spaces using classical invariant theory, orbit decomposition of prehomogeneous vector spaces, and compact reductive homogeneous space such as Grassmann manifold and flag variety. Finally, we go back to the original dressed photon with n=4,r=2,s=1.

We consider a certain tiling problem of a planar region in which there are no long horizontal or vertical strips consisting of copies of the same tile. Intuitively speaking, we would like to create a dappled pattern with two or more kinds of tiles. We give an efficient algorithm to turn any tiling into one satisfying the condition, and discuss its applications in texturing.

Good parametrizations of affine transformations are essential to interpolation, deformation, and analysis of shape, motion, and animation. It has been one of the central research topics in computer graphics. However, there is no single perfect method and each one has both advantages and disadvantages. In this paper, we propose a novel parametrization of affine transformations, which is a generalization to or an improvement of existing methods. Our method adds yet another choice to the existing toolbox and shows better performance in some applications. A C++ implementation is available to make our framework ready to use in various applications.

The wnt protein family has important members involved in cell differentiation, proliferation and plasticity expression; however, little is known about its biosynthesis processes. On the other hand, an increase in the intracerebral cyclic adenosine 3', 5'-monophosphate (cAMP) level leads to synaptic plasticity via the de novo synthesis of any protein. Here, the effect of dibutyryl cAMP (dbcAMP), a membrane permeability cAMP analog, on the wnt family was investigated in rat primary-cultured glial cells containing astrocytes and microglia. Among wnt3a, 4, 5a, 7a and 11 mRNA, only wnt4 expression was increased by longer treatment (24 h), compared with short treatment (2 h), with dbcAMP in a concentration-dependent manner, and its effect reached statistical significance at 1 mM. In cultures of isolated astrocytes or microglia, wnt4 expression was not affected by 1 mM dbcAMP for 24 h, and microglial wnt4 protein was undetectable even when cells were treated with the drug. Mixed glial cells treated for 24 h with 1 mM dbcAMP showed significantly increased wnt4 protein, as well as mRNA. Immunofluorescence manifested that cells that expressed wnt4 protein were astrocytes, but not microglia. Intraperitoneal injection of 1.25 mg/kg rolipram, a phosphodiesterase (PDE) IV inhibitor that can pass through the blood brain barrier and inhibits cAMP degradation specifically, showed a tendency to increase wnt4 expression in the adult rat brain after 24 h, and the increases in wnt4 mRNA and protein levels reached statistical significance in the hippocampus and striatum, respectively. This is the first finding to help elucidate the selective biosynthesis of central wnt4 through cAMP-stimulated microglia and astrocytes interaction.

We implemented a Mathematica module of CGA which includes functions to denote CGA elements and compute several operations in CGA. We can draw the figure in 3D space which is corresponding to a CGA element. Our draw function is using Gr\"{o}bner Basis for simplifying equations of figures. It can be used for any dimensional figures. One of our motivations is to realize 3D origami system using our own CGA Library. We follow the 2D computational origami system E-Origami-System developed by Ida et.al. and formulated simple fold operations in 3D by using CGA points and motions. Then, we proved some geometric theorems about origami properties by computing CGA equation formulas.

It is well-known that one-dimensional time fractional diffusion-wave equations with variable coefficients can be reduced to ordinary fractional differential equations and systems of linear fractional differential equations via scaling transformations. We then derive exact solutions to classes of linear fractional differential equations and systems thereof expressed in terms of Mittag-Leffler functions, generalized Wright functions and Fox H-functions. These solutions are invariant solutions of diffusion-wave equations obtained through certain transformations, which are briefly discussed. We show that the solutions given in this work contain previously known results as particular cases., Comment: 25 pages

We prove, for graphical models for nearest neighbour interactions, a conjecture stated by Letac and Massam in 2007. Our result is important in the analysis of Wishart distributions on cones related to graphical models and in its statistical applications.

Let K be a complex quadratic extension of and let denote the adeles of K. We find special values at all of the critical points of twisted tensor L-functions attached to cohomological cuspforms on GL2() and establish Galois equivariance of the values. To investigate the values, we determine the archimedean factors of a class of integral representations of these L–functions, thus proving a conjecture due to Ghate. We also investigate analytic properties of these L–functions, such as their functional equations.

Let $ G $ be a connected reductive algebraic group over $ \C $. We denote by $ K = (G^{\theta})_{0} $ the identity component of the fixed points of an involutive automorphism $ \theta $ of $ G $. The pair $ (G, K) $ is called a symmetric pair. Let $Q$ be a parabolic subgroup of $K$. We want to find a pair of parabolic subgroups $P_{1}$, $P_{2}$ of $G$ such that (i) $P_{1} \cap P_{2} = Q$ and (ii) $P_{1} P_{2}$ is dense in $G$. The main result of this article states that, for a simple group $G$, we can find such a pair if and only if $(G, K)$ is a Hermitian symmetric pair. The conditions (i) and (ii) yield to conclude that the $K$-orbit through the origin $(e P_{1}, e P_{2})$ of $G/P_{1} \times G/P_{2}$ is closed and it generates an open dense $G$-orbit on the product of partial flag variety. From this point of view, we also give a complete classification of closed $K$-orbits on $G/P_{1} \times G/P_{2}$., Comment: 7 pages

Let $ G $ be a connected, simply connected semisimple algebraic group over the complex number field, and let $ K $ be the fixed point subgroup of an involutive automorphism of $ G $ so that $ (G, K) $ is a symmetric pair. We take parabolic subgroups $ P $ of $ G $ and $ Q $ of $ K $ respectively and consider the product of partial flag varieties $ G/P $ and $ K/Q $ with diagonal $ K $-action, which we call a \emph{double flag variety for symmetric pair}. It is said to be \emph{of finite type} if there are only finitely many $ K $-orbits on it. In this paper, we give a parametrization of $ K $-orbits on $ G/P \times K/Q $ in terms of quotient spaces of unipotent groups without assuming the finiteness of orbits. If one of $ P \subset G $ or $ Q \subset K $ is a Borel subgroup, the finiteness of orbits is closely related to spherical actions. In such cases, we give a complete classification of double flag varieties of finite type, namely, we obtain classifications of $ K $-spherical flag varieties $ G/P $ and $ G $-spherical homogeneous spaces $ G/Q $., 47 pages, 3 tables; add all the details of the classification

This synthesis lecture presents an intuitive introduction to the mathematics of motion and deformation in computer graphics. Starting with familiar concepts in graphics, such as Euler angles, quaternions, and affine transformations, we illustrate that a mathematical theory behind these concepts enables us to develop the techniques for efficient/effective creation of computer animation. This book, therefore, serves as a good guidepost to mathematics (differential geometry and Lie theory) for students of geometric modeling and animation in computer graphics. Experienced developers and researchers will also benefit from this book, since it gives a comprehensive overview of mathematical approaches that are particularly useful in character modeling, deformation, and animation. Table of Contents: Preface / Symbols and Notations / Introduction / Rigid Transformation / Affine Transformation / Exponential and Logarithm of Matrices / 2D Affine Transformation between Two Triangles / Global 2D Shape Interpolation / Parametrizing 3D Positive Affine Transformations / Further Readings / Bibliography / Authors' Biographies

The claudin family comprises four-pass transmembrane proteins involved in the formation of tight junctions (TJs). Relatively recently, claudin domain containing (CLDND) 1, also known as claudin-25, was identified as a novel member of the claudin family. In the present study, we revealed that in the adult murine brain, CLDND1 is abundant in the cerebellum among common sites of intracerebral hemorrhage. Thus, the dynamics of CLDND1 after cerebellar hemorrhage were examined. Both CLDND1 mRNA and protein levels transiently decreased at 24 hr after hemorrhagic insult. For immunostaining, an anti-CLDND1 antibody that recognizes the specific epitope in the extracellular first loop was prepared. Dual immunohistochemical staining with CD31 using coronal cryosections of intact murine cerebellum tissue revealed that CLDND1 is expressed on endothelial cells. We therefore performed an in vitro permeability test using a human brain endothelial cell (HBEC) line to reveal whether CLDND1 contributes to cell adhesion like other claudins. CLDND1 was expressed on HBECs as well as in murine cerebellum tissue, and a strong signal was observed at TJs. RNA interference against CLDND1 decreased both the mRNA and protein levels without cytotoxicity. The permeability to small molecules, but not to large ones, across confluent HBECs increased on CLDND1 knockdown compared with mock-treated cells. These results suggest that the transient decrease of CLDND1 after cerebellar hemorrhage is responsible for low-molecular-weight selective vascular hyperpermeability. © 2017 Wiley Periodicals, Inc.

This course presents an elementary, intuitive, and visual introduction to several mathematical basics for beginners in computer graphics. The mathematical concepts covered in this course include 2D/3D translation, rotation, affine transformation, quaternion, dual quaternion, exponential and logarithm. These are quite useful for various aspects of computer graphics, including curve/surface editing, deformation and animation of geometric objects. On one hand we don't assume that the audience has familiarity with such mathematical concepts. Elements of linear algebra and calculus at undergraduate level are sufficient for the attendees of this course. To clarify the relation between these concepts and computer graphics practice, several graphics techniques will also be demonstrated, such as morphing (ARAP), cage-based deformation and Poisson mesh editing.

Micro Spark Coating (MSC) has been developed as a new functional coating process for Ni-based superalloys used in advanced gas turbines. In this study, some metallurgical and mechanical properties of a MSC layer made of a Co-based wear resisting alloy (X40), and its influence on the high temperature fatigue properties of Ni-based superalloy, Alloy718, were investigated. Prior evaluation of the metallurgical and mechanical properties of the MSC layer that the cavity fraction of MSC layer significantly decreased during the thermal exposure period at 650°C associating with the generation of an oxide phase, progressive sintering and the subsequent increase in hardness and elastic modulus of MSC layer. However, at 480°C these changes were not significant even after 1000hrs exposure. It was found from the high temperature fatigue tests at 480°C and 650°C that the fatigue life of the specimen with MSC layer was almost comparable to that of bare Alloy718 specimen at 480°C, while at 650°C the life of the former was slightly longer than that of the latter. These results suggested that the MSC would have a potential to add a new function to Ni-based superalloy without a reduction in fatigue properties at elevated temperature.

We explicitly give new group invariant solutions to a class of Riemann-Liouville time fractional evolution systems with variable coefficients. These solutions are derived from every element in an optimal system of Lie algebras generated by infinitesimal symmetries of evolution systems in the class. We express the solutions in terms of Mittag-Leffler functions, generalized Wright functions, and Fox H-functions and show that these solutions solve diffusion-wave equations with variable coefficients. These solutions contain previously known solutions as particular cases. Some plots of solutions subject to the order of the fractional derivative are illustrated.

The non-commutative harmonic oscillator is a 2×2-system of harmonic oscillators with a non-trivial correlation. We write down explicitly the special value at s=2 of the spectral zeta function of the non-commutative harmonic oscillator in terms of the complete elliptic integral of the first kind, which is a special case of a hypergeometric function.

Let V be a neighborhood of a singular locus of a hyperbolic 3-cone-manifold, which is a quotient space of the 3-dimensional hyperbolic space. In this paper we give an explicit expression of a harmonic vector field v on the hyperbolic manifold V in terms of hypergeometric functions. The expression is obtained by solving a system of ordinary differential equations which is induced by separation of the variables in the vector-valued partial differential equation (∆ + 4)τ = 0, where ∆ is the Laplacian of V and τ is the dual 1-form of v. We transform this system of ordinary differential equations to single-component differential equations by elimination of unknown functions and solve these equations. The most important step in solving them consists of two parts, decomposing their differential operators into differential operators of the type appearing in Riemann’s P -equation in the ring of differential operators and then describing the projections to the components of this decomposition in terms of differential operators that are also of the type appearing in Riemann’s P -equation.

We prove existence of scaling limits of sequences of functions defined by the recursion relation w′n+1(x) = –wn(x)2. which is a successive approximation to w′(x) = –w(x)2, a simplest non-linear ordinary differential equation whose solutions have moving singularities. Namely, the sequence approaches the exact solution as n → ∞ in an asymptotically conformal way, wn(x) $\\asymp$ qn $\\bar w$(qnx), for a sequence of numbers {qn} and a function $\\bar w$. We also discuss implication of the results in terms of random sequential bisections of a rod.

We consider the connection problem for the Heun differential equation, which is a Fuchsian differential equation that has four regular singular points. We consider the case in which the parameters in this equation satisfy a certain set of conditions coming from the eigenvalue problem of the non-commutative harmonic oscillators. As an application, we describe eigenvalues with multiplicities greater than 1 and the corresponding odd eigenfunctions of the non-commutative harmonic oscillators. The existence of a rational or a certain algebraic solution of the Heun equation implies that the corresponding eigenvalues has multiplicities greater than 1.

The hypergeometric equations with polyhedral monodromy groups derive 3-integral-parameter families of polynomials.

We propose a method for representing the solutions of a certain type of ordinary differential operator L in terms of those of more fundamental differential operators. This method consists of two steps, decomposing L in the ring of differential operators and then describing the projections to the components of this decomposition also in terms of some differential operators. We provide a concrete algorithm for the application of this method and show that this algorithm is successful for a specific example of a 6-th order homogeneous linear ordinary differential operator of Fuchsian type with three singular points.

The visual simulation of fluids has become an important element in many applications, such as movies and computer games. In these applications, large-scale fluid scenes, such as fire in a village, are often simulated by repeatedly rendering multiple fluid flows. In these cases, animators are requested to generate many variations of a fluid flow. Previously, we developed a method to help animators meet such requirements [Sato et al. 2013]. However, the method was limited to 2D fluid simulation. In the previous method [Sato et al. 2013], we use Laplacian eigenfunctions as the basis functions. However, Laplacian eigenfunctions are too expensive in computation and storage costs for 3D fluid simulation. Furthermore, Laplacian eignfunctions force us to use slip boundary conditions and this makes the method less practical. In order to address these problems, we introduce Principal Component Analysis (PCA) for the basis functions. In generating the principal components of the input velocity fields, we use a subspace approach [Treuille et al. 2006; Kim and Delaney 2013]. The variations are generated by modulating the coefficient of each principal component.

A sensitive and specific analytical method for a potent antitumor agent, TZT-1027, in plasma has been developed using liquid chromatography–mass spectrometry (LC–MS) with [2H4]TZT-1027 as an internal standard (I.S.). A plasma sample was purified by solid-phase extraction on a C18 cartridge, followed by solvent extraction with diethyl ether. The extract was then injected into the LC–MS system. Chromatography was carried out on a C18 reversed-phase column using acetonitrile–0.05% trifluoroacetic acid (TFA) (55:45) as a mobile phase. Mass spectrometric analysis was performed in atmospheric pressure chemical ionization (APCI) mode with positive ion detection, and the protonated molecular ions ([M+H]+) of TZT-1027 and I.S. were monitored to allow quantitation. The method was applied to the determination of TZT-1027 in human, monkey, dog, rat and mouse plasma. As far as the sample preparation was concerned, good recoveries (73.5–99.1%) were obtained. The calibration curves were linear over the range of 0.25–100 ng per 1 ml of human, dog and rat plasma, per 0.5 ml of monkey plasma, and per 0.1 ml of mouse plasma. From the intra- and inter-day accuracy and precision, the present method satisfies the accepted criteria for bioanalytical method validation. TZT-1027 was stable when stored below −15°C for 6 months in human plasma and for 3 weeks in plasma from other species. TZT-1027 was also stable in plasma through at least three freeze–thaw cycles.

For a prime p and for the number a(n) of solutions of xp = 1 in the symmetric group on n letters, ordp\( (a(n)) \geq [n/p] - [n/p^2] \), and especially, ordp\( (a(n)) = [n/p] - [n/p^2] \) provided \( n \equiv 0 \) mod p2. Let r be an integer with \( 1 \leq r \leq p^2 - 1 \). If ordp\( (a(r)) \leq [r/p] + 1 \), then, for each positive integer m, ordp\( (a(mp^2 + r)) = m(p-1)+ ord_p (a(r)) \). Assume that ordp\( (a(r)) = [r/p] + 2 \). If \( a(p^2 + r) \equiv -p^{p-1} a(r) mod \quad p^{p+[r/p]+2} \), then ordp\( (a(mp^2 + r)) = m(p-1) + [r/p] + 2 \); otherwise, there exists a p-adic integer b such tha ordp\( (a(mp^2 + r)) = m(p-1) + [r/p] + 2 + ord_p(m-b) \).

The spectral problem for non-commutative harmonic oscillators is shown to be equivalent to solve Fuchsian ordinary differential equations with four regular singular points in a complex domain.

This chapter is intended to give a summary of Lie groups and Lie algebras for computer graphics, including an example from interpolations and blending of motions and deformation. In animation and filmmaking procedure, we want to get a smooth transition of the drawing of given starting and ending point (the drawings at these points are called key frame). This problem can be understood as an interpolation, so that various approach have been proposed and used in Computer Graphics. After the seminal work so-called ARAP (as-rigid-as-possible), serious properties of matrix groups have been taken into account both in theoretical and in computational point of view. To understand and develop these properties, we here employ a Lie theoretic approach.