bluuebunny/crossref_metadata_2025 huggingface dataset:
On Correspondences Between Unary Algebras, Automata, Semigroups and Congruences
Authors: Petković T. , Ćirić M. , Bogdanović S.
Published: February 2014

In this paper, we give correspondences between unary algebras, semigroups and congruences on free semigroups. We establish isomorphisms between the complete lattice of varieties of semigroups and the complete lattices of families of varieties of unary algebras, and families of filters of congruences on free semigroups. Similar correspondences between generalized varieties and pseudovarieties of semigroups and corresponding families of algebras and congruences are also established.
On 2-Symmetric Words and Verbal Subgroup of Metabelian Product of Abelian Groups
Authors: Pan Jiangmin
Published: February 2014

Let F be the free group of rank 2 with basis {x, y}, and G a metabelian product of some non-trivial abelian groups. If not all the factors of G are torsion groups, it is proved that the verbal subgroup of G in F equals F″. Moreover, all the 2-symmetric words of G are determined by using left Fox derivatives. In addition, we provide an example to illustrate that if all the factors of G are torsion groups, the above results need not be true.
Finite Solvable Groups Whose Character Degree Graphs Are Not Complete
Authors: Zhang Jiping
Published: February 2014

In this paper, we characterize the finite solvable groups with non-complete character degree graphs by proving the following theorem, which generalizes a conjecture by Huppert.

Suppose that G is a finite solvable group and p is a prime number dividing the degree of some irreducible character of G. If there is another such prime number q such that pq does not divide the degree of any irreducible character of G, then both p-length ℓp(G) and q-length ℓq(G) of G are at most two, and ℓp(G)+ ℓq(G)=4 if and only if pq=6 with QG/Zφ(QG)≅ 32:GL(2,3), where QG is generated by all Sylow 2-subgroups of G and Zφ(G) is a normal nilpotent subgroup of G. Moreover, the bounds are best possible.
The Cancellation Property of Projective Modules
Authors: Zhang Hongbo , Tong Wenting
Published: February 2014

An R-module M is said to have the cancellation property provided that M⊕ B ≅ M⊕ C implies B ≅ C for any pair of R-modules B and C. We obtain a characterization of the cancellation property for projective R-modules. With this result, it is proved that Dedekind domains have the cancellation property; and if R is a Prüfer domain, then R⊕ B ≅ R⊕ C implies B ≅ C for any pair of finitely generated R-modules B and C.
On ${\mathcal U}_c$-Normal Subgroups of Finite Groups
Authors: Alsheik Ahmad A. Y. , Jaraden J. J. , Skiba Alexander N.
Published: February 2014

Let G be a finite group. We say that a subgroup H of G is [Formula: see text]-normal in G if G has a subnormal subgroup T such that TH = G and (H ∩ T)HG/HG is contained in the [Formula: see text]-hypercenter [Formula: see text] of G/HG, where [Formula: see text] is the class of the finite supersoluble groups. We study the structure of G under the assumption that some subgroups of G are [Formula: see text]-normal in G.
Some Remarks on the Tensor Product of Algebras and Applications II
Authors: Harris Morton E.
Published: February 2014

We apply the G-algebra theory to the tensor product of algebras. These considerations are applied to extend the results of Alghamdi and Khammash [1], Khammash [4] and Külshammer [5, Proposition 1.2] on the tensor product of group algebras and modules over an algebraically closed field to lattices over a complete discrete valuation ring. This places these results in the standard integral finite group modular representation theory of G-algebras as pioneered by Puig (cf. [8]). We also study some aspects of covering homomorphisms and the Green correspondence in this context (cf. [8, Sections 20 and 25]).
On Superabundant Semigroups Whose Set of Idempotents Forms a Subsemigroup
Authors: Ren X. M. , Shum K. P.
Published: February 2014

In this paper, we study the structure of a superabundant semigroup S whose set of idempotents E(S) forms a subsemigroup. We call such a semigroup a cyber-group because it is a generalization of orthogroups in the class of completely regular semigroups studied by Petrich and Reilly. We show that a cyber-group can be expressed as a semilattice of rectangular monoids. Thus, our result generalizes the well-known result obtained by Petrich in 1987 for orthogroups. Some properties of cyber-groups are given and some special superabundant semigroups are discussed.
Generalized Co-Cohen–Macaulay and Co-Buchsbaum Modules
Authors: Cuong Nguyen Tu , Dung Nguyen Thi , Nhan Le Thanh
Published: February 2014

We study two classes of Artinian modules called co-Buchsbaum modules and generalized co-Cohen–Macaulay modules. Some basic properties and characterizations of these modules in terms of 𝔮-weak co-sequences, co-standard sequences, multiplicity, local homology modules are presented.
A Class of Nonassociative Algebras
Authors: Goze Michel , Remm Elisabeth
Published: February 2014

In this paper, we classify the nonassociative algebras whose associator satisfies relations defined by a natural action of the symmetric group of degree 3.
Automorphism Groups of Connected Cubic Cayley Graphs of Order 4p
Authors: Zhou Chuixiang , Feng Yan-Quan
Published: February 2014

For a prime p, let D4p be the dihedral group 〈a,b | a2p = b2 = 1, b-1ab = a-1〉 of order 4p, and Cay (G,S) a connected cubic Cayley graph of order 4p. In this paper, it is shown that the automorphism group Aut ( Cay (G,S)) of Cay (G,S) is the semiproduct R(G) ⋊ Aut (G,S), where R(G) is the right regular representation of G and Aut (G,S) = {α ∈ Aut (G) | Sα = S}, except either G = D4p (p ≥ 3), Sβ = {b,ab,apb} for some β ∈ Aut (D4p) and [Formula: see text], or Cay (G,S) is isomorphic to the three-dimensional hypercube Q3[Formula: see text] and G = ℤ4 × ℤ2 or D8.
On Finite Presentability of Bruck–Reilly Extensions of a Monoid with Respect to an Endomorphism and Its Powers
Authors: Carvalho C. A. , Ruškuc N.
Published: February 2014

Let M be a monoid and let θ be an endomorphism of M. We prove that if the Bruck–Reilly extension BR(M, θ) is finitely presented, then the Bruck–Reilly extension BR(M, θm) is also finitely presented for all m ⩾ 1.
Induced Modules of Semisimple Hopf Algebras
Authors: Hu Jun , Zhang Yinhuo
Published: February 2014

Let K be a field. Let H be a finite-dimensional K-Hopf algebra and D(H) be the Drinfel'd double of H. In this paper, we study Radford's induced module Hβ, where β is a group-like element in H∗. Using the commuting pair established in [7], we obtain an analogue of the class equation for [Formula: see text] when H is semisimple and cosemisimple. In case H is a finite group algebra or a factorizable semisimple cosemisimple Hopf algebra, we give an explicit decomposition of each Hβ into a direct sum of simple D(H)-modules.
Another Existence and Uniqueness Proof of the Tits Group
Authors: Michler Gerhard O. , Wang Lizhong
Published: February 2014

In this article we give a self-contained existence and uniqueness proof for the Tits simple group T. Parrott gave the first uniqueness proof. Whereas Tits' and Parrott's results employ the theory of finite groups of Lie type, our existence and uniqueness proof follows from the general algorithms and uniqueness criteria for abstract finite simple groups described in the first author's book [11]. All we need from the previous papers is the fact that the centralizer H of the Tits group T is an extension of a 2-group J with order 29 and nilpotency class 3 by a Frobenius group F of order 20 such that the center Z(H) has order 2 and any Sylow 5-subgroup Q of H has a centralizer CJ(Q) ≤ Z(H).
Classification and Isomorphisms of Non-degenerate Solvable Lie Algebras of Maximal Rank
Authors: Zhang Haishan , Lu Caihui
Published: February 2014

The classification of nilpotent Lie algebras of maximal rank was solved by Santharoubane. In the present paper, we prove that the classification of non-degenerate solvable Lie algebras of maximal rank can be obtained from the work of Santharoubane.
The Influence of Certain Abelian Subgroups on the Structure of Finite Groups
Authors: Ramadan M.
Published: February 2014

Let G be a finite group. A subgroup K of a group G is called an [Formula: see text]-subgroup of G if NG(K) ∩ Kx ≤ K for all x ∈ G. The set of all [Formula: see text]-subgroups of G is denoted by [Formula: see text]. In this paper, we investigate the structure of a group G under the assumption that certain abelian subgroups of prime power order belong to [Formula: see text].
Endomorphisms of Progenerators over Exchange QB-Rings
Authors: Chen Huanyin
Published: February 2014

In this paper, we characterize exchange QB-rings by endomorphisms of progenerators. Let A be a progenerator over an exchange ring R. It is shown that R is a QB-ring if and only if whenever f, g, h ∈ End RA satisfy fA + gA = hA, there exist [Formula: see text] and l ∈ End RA such that fk + gl = h. Some applications are also obtained.
On the Associated Primes and the Support of Local Cohomology Modules
Authors: Chinh Nong Quoc , Nhan Le Thanh
Published: February 2014

In this paper, we introduce the notion of k-depth to study the associated primes and the support of local cohomology modules. A result on non-vanishing of local cohomology modules is given.
Non-associative Algebras with n-Exponential Functions
Authors: Lee Jongwoo , Choi Seul Hee , Nam Ki-Bong
Published: February 2014

Dernon(𝔽[x1, x2, …, xn]Mn) of the evaluation algebra 𝔽[x1, x2, …, xn]Mnand Dernon(𝔽[e± x1, e± x2, …, e± xn]Mn) of the evaluation algebra 𝔽[e± x1, e± x2, …, e± xn]Mnare found in [2] and [4], respectively, where Mn= {∂1, …, ∂n}. In this work we find [Formula: see text] of the algebra [Formula: see text]. We define a finite dimensional semi-Lie algebra which is simple. We define a simple semi-Lie ring whose dimension is finite.
Congruences on Nilpotent-generated Partial Transformation Semigroups
Authors: Marques-Smith M. Paula O. , Sullivan R. P.
Published: February 2014

In 1987, Sullivan characterised the elements of the semigroup NP(X) generated by the nilpotents in P(X), the semigroup (under composition) consisting of all partial transformations of a set X; and in 1999, Marques-Smith and Sullivan determined all the ideals of NP(X) for arbitrary X. In this paper, we use that work to describe all the congruences on NP(X).
On General Injective Rings with Chain Conditions
Authors: Thuyet Le Van , Quynh Truong Cong
Published: February 2014

Kupisch proved that if R is a left and right artinian QF-2 ring and Sr = Sl, then R is QF. A weaker condition for a ring to be a QF ring was obtained by Dan and Thuyet. They proved that if R is a right artinian QF-2 ring and Sr ≤ Sl, then R is QF. In this paper, we prove that if R is a QF-2 ring satisfying ACC on right annihilators in which Sl ≤ eRR (e.g., Sr ≤ Sl with Sr ≤e RR), then R is QF. It is also proved that R is QF if and only if R is a left ef-extending, right continuous ring with ACC on right annihilators.
In,d-Preenvelope Dimension and Pn,d-Precover Dimension
Authors: Li Weiqing , Ouyang Baiyu
Published: February 2014

We introduce the concept of the right In,d-preenvelope dimension as a generalization of the injective dimension for modules and rings. It measures how far away a right module from being (n,d)-injective, and how far away a ring from being a right (n,d)-ring. Dually, the concept of the Pn,d-precover dimension is also introduced, which measures how far away a right module from being (n,d)-projective, and how far away a ring R from satisfying that every right R-module is (n,d)-projective. We apply right derived functors to characterize these dimensions.
Lie Tori and Their Fixed Point Subalgebras
Authors: Azam Saeid , Khalili Valiollah
Published: February 2014

We study the fixed point subalgebra of a centerless irreducible Lie torus under a certain finite order automorphism. We investigate which axioms of a Lie torus hold for the fixed points and which do not. We relate our study to some recent results about the fixed points of extended affine Lie algebras under a class of finite order automorphisms.
On the Vanishing of the First André–Quillen Homology
Authors: Ionescu Cristodor
Published: February 2014

We study algebras A → B with the property that H1(A,B,B)=0. They are quite near to smooth algebras, that is why they are called almost smooth algebras. Some applications to the evolution problem of Eisenbud and Mazur are given.
Influence of the Strong Theta Completions on Finite Groups
Authors: Du Ni , Li Shirong
Published: February 2014

Let G be a finite group. By using the concept of strong θ-completions for maximal subgroups of G, we obtain in this paper some new conditions under which G is solvable or supersolvable.
Morphic Properties of Extensions of Rings
Authors: Huang Qinghe , Chen Jianlong
Published: February 2014

An element a in a ring R is called left morphic if R/Ra ≅ ℓR(a), where ℓR(a) denotes the left annihilator of a in R. A ring R is said to be left morphic if every element is left morphic. In this paper, it is shown that if I is an ideal of a unit regular ring R, then for each positive integer n, [Formula: see text] is a left morphic ring. This extends two recent results of Lee and Zhou. It is also proved that if R is a strongly regular ring and Cn= 〈g〉 is a cyclic group of order n ≥ 2, then for any r ∈ R, 1 + rg is morphic in the group ring RCn.
Generalized Heisenberg Algebras and Toroidal Lie Algebras
Authors: Fang Yingjue , Peng Liangang
Published: February 2014

In this article we provide two kinds of infinite presentations of toroidal Lie algebras. At first we define generalized Heisenberg algebras and prove that each toroidal Lie algebra is an amalgamation of a simple Lie algebra and a generalized Heisenberg algebra in the sense of Saito and Yoshii. This is one kind of presentations of toroidal Lie algebras given by the generators of generalized Heisenberg algebras and the Chevalley generators of simple Lie algebras with certain amalgamation relations. Secondly by using the generalized Chevalley generators, we give another kind of presentations. These two kinds of presentations are different from those given by Moody, Eswara Rao and Yokonuma.
On Quasisupersoluble and p-Quasisupersoluble Finite Groups
Authors: Guo Wenbin , Skiba Alexander N.
Published: February 2014

Let G be a finite group and p a prime. We say that G is quasisupersoluble (resp., p-quasisupersoluble) if for every non-cyclic chief factor H/K of G (resp., for every non-cyclic chief factor H/K of G of order divisible by p), every automorphism of H/K induced by an element of G is inner. In this paper, we study the structure of quasisupersoluble and p-quasisupersoluble finite groups.
A Class of Imprimitive Groups
Authors: Bartolone Claudio , Ciraulo Francesco
Published: February 2014

We classify imprimitive groups inducing the alternating group A4 on the set of blocks, with the inertia subgroup satisfying some very natural geometrical conditions which force the group to operate linearly.
Complexes of FP-injective Modules
Authors: Geng Yuxian
Published: February 2014

In this paper, we study the class [Formula: see text] of complexes of FP-injective left R-modules. It is shown that the pair [Formula: see text] is a complete cotorsion pair. If R is a left coherent ring, it is proved that every complex has an [Formula: see text]-cover. We also introduce the FP-injective dimension of complexes. A special attention is paid to the dimension of homologically bounded above R-complexes over a left coherent ring which has a nice functorial description.
Relatively Lifting Modules
Authors: Crivei Septimiu
Published: February 2014

We consider a generalization of lifting modules relative to a class [Formula: see text] of modules and a proper class 𝔼 of short exact sequences of modules. These modules will be called 𝔼-[Formula: see text]-lifting. We establish characterizations of modules with the property that every direct sum of copies of them is 𝔼-[Formula: see text]-lifting.
Automorphism Group of a Special Type Lie Algebra I
Authors: Choi Seul Hee , Nam Ki-Bong
Published: February 2014

In an earlier paper, we defined a degree stable Lie algebra, and determined the Lie algebra automorphism group AutLie(S+(2)) of the Lie algebra S+(2). In this paper, we determine the Lie algebra automorphism group AutLie(S(1,0,2)) of the Lie algebra S(1,0,2).
Abundant Semigroups of Transformations Preserving an Equivalence Relation
Authors: Pei Huisheng , Zhou Huijuan
Published: February 2014

Let X be a set with |X| ≥ 3, [Formula: see text] the full transformation semigroup on X, and E an equivalence relation on X. Let TE(X) be the set of transformations f in [Formula: see text] which preserve E, i.e., (x,y) ∈ E implies (f(x),f(y)) ∈ E. It is known that TE(X) is a subsemigroup of [Formula: see text]. In this paper, we describe the equivalence relations E so that the semigroup TE(X) is abundant.
Analysis of the Number of Terms in the Generation Polynomial of the Decimation Sequence
Authors: Zheng Jianhua
Published: February 2014

In this paper, we discuss the relationship between the generation polynomial of a linear sequence and its decimation sequence over the finite field 𝔽2. Then we propose an upper bound of the number of terms in the generation polynomial of a decimation sequence of a linear sequence whose generation polynomial is trinomial. Finally, we suggest a method to calculate the terms of a decimation polynomial and their number directly, which can be used in the construction of irreducible polynomials with a controlled number of terms, when the source trinomial and the decimation distance satisfy a certain condition.
Non-singular Equations over Groups I
Authors: Edjvet M. , Juhász A.
Published: February 2014

Let G be a group, t an element distinct from G and r(t)= g1tl1 ⋯ gktlk∈ G ∗ 〈t 〉, where each gi is an element of G of order greater than 2 and the li are non-zero integers such that l1+l2+ ⋯ +lk≠ 0 and |li| ≠ |lj| for i ≠ j. It is known that if k≤ 2, then the natural map from G to the one-relator product 〈G,t | r(t)〉 is injective. In this paper, we prove that the same holds for all k ∉ {4, 5}.
Archimedean Orders on Certain Rings of Invariants
Authors: Tesemma Mohammed , Wang Haohao
Published: February 2014

Let [Formula: see text] act multiplicatively on the Laurent polynomial algebra k[x± 1] in n indeterminates x={x1, …,xn}. Consider the initial algebra of the ring of invariants [Formula: see text] with respect to some monomial order. We set a sufficient condition on [Formula: see text] such that each initial algebra is represented by some weight vectors in ℝn. We also show that the condition is necessary in the case where the rank n = 2.
A Class of Finite-dimensional Lie Superalgebras of Hamiltonian Type
Authors: Ren Li , Mu Qiang , Zhang Yongzheng
Published: February 2014

A class of finite-dimensional Cartan-type Lie superalgebras H(n,m) over a field of prime characteristic is studied in this paper. We first determine the derivation superalgebra of H(n,m). Then we obtain that H(n,m) is restrictable and it is an extension of the Lie superalgebra [Formula: see text]. Finally, we prove that H(n,m) is isomorphic to a subalgebra of the restricted Hamiltonian Lie superalgebra [Formula: see text].
θ-Closure and θ-Parts of Hypermodules
Authors: Anvariyeh S. M. , Davvaz B.
Published: February 2014

We introduce the classes of θ-parts, θ-closure and [Formula: see text]-complete hypermodules, and study the relation between them. Also, several properties are found.
On the Unions of Ascending Chains of Direct Sums of Ideals of h-Local Prüfer Domains
Authors: Macías-Díaz J. E.
Published: February 2014

In this work, we investigate conditions under which unions of ascending chains of modules which are isomorphic to direct sums of ideals of an integral domain are again isomorphic to direct sums of ideals. We obtain generalizations of the Pontryagin-Hill theorems for modules which are direct sums of ideals of h-local Prüfer domains. Particularly, we prove that a torsion-free module over a Dedekind domain with a countable number of maximal ideals is isomorphic to a direct sum of ideals if it is the union of a countable ascending chain of pure submodules which are isomorphic to direct sums of ideals.
Annihilator-small Right Ideals
Authors: Nicholson W. K. , Zhou Yiqiang
Published: February 2014

A right ideal A of a ring R is called annihilator-small if A+T=R, T a right ideal, implies that [Formula: see text], where [Formula: see text] indicates the left annihilator. The sum Ar of all such right ideals turns out to be a two-sided ideal that contains the Jacobson radical and the left singular ideal, and is contained in the ideal generated by the total of the ring. The ideal Ar is studied, conditions when it is annihilator-small are given, its relationship to the total of the ring is examined, and its connection with related rings is investigated.
Decompositions of Weak BCC-Algebras
Authors: Karamdin Bushra , Bhatti Shaban A.
Published: February 2014

It is proved that a decomposition of a weak BCC-algebra X into branches induces on X a congruence θ such that the algebra X/θ is isomorphic to the subalgebra of X containing all initial elements of X. A decomposition of a medial weak BCC-algebra into a direct product of subalgebras generated by one element is also presented.
Branches and Ideals of Weak BCC-Algebras
Authors: Dudek Wiesław A. , Karamdin Bushra , Bhatti Shaban Ali
Published: February 2014

Basic properties of branches of weak BCC-algebras and connections between various types of ideals are described. Next, a new type of ideals with the property that the quotient algebras induced by these ideals are uniquely determined by some groups is introduced and characterized.
Twisted Modules and Pseudo-endomorphisms
Authors: Li Haisheng
Published: February 2014

We exhibit a connection between two constructions of twisted modules for a general vertex operator algebra with respect to inner automorphisms. We also study pseudo-derivations, pseudo-endomorphisms, and twist deformations of ordinary modules by pseudo-endomorphisms.
Skew Range-inclusive Maps in Rings with Idempotents
Authors: Wang Yu
Published: February 2014

Let A be a ring, let M be an A-bimodule, and let C be the center of M. A map F: A → M is said to be range-inclusive (respectively, skew range-inclusive) if [A,F(x)] ⊆ [x,M] for every x ∈ A (respectively, A ◦ F(x) ⊆ x ◦ M for every x ∈ A). Recently, Brešar investigated range-inclusive maps from a unital ring with wide idempotents into a unital A-bimodule. In this paper, our main purpose is to investigate skew range-inclusive maps from a unital ring with wide idempotents into a unital 2-torsion free A-bimodule.
Lifting to Cluster-tilting Objects in Higher Cluster Categories
Authors: Liu Pin
Published: February 2014

Let d > 1 be a positive integer. In this note, we consider the d-cluster-tilted algebras, i.e., algebras which appear as endomorphism rings of d-cluster-tilting objects in higher cluster categories (d-cluster categories). We show that tilting modules over such algebras lift to d-cluster-tilting objects in the corresponding higher cluster category.
Differential Representations of the Lie Superalgebra C(n+1)
Authors: Wu Yuezhu , Yue Xiaoqing , Zhu Linsheng
Published: February 2014

In this paper, we realize Verma modules and the vector-coherent-state (VCS) representations of the orthosymplectic Lie superalgebra osp(2|2n) as differential operators with vector coefficients. We also characterize simple sub-representations of VCS representations as kernels of some finite number of differential operators. The singular vectors of the atypical representation of osp(2|2n) are explicitly given.
A Finiteness Result for Attached Primes of Certain Tor-Modules
Authors: Nhan Le Thanh , Dung Nguyen Thi
Published: February 2014

In this paper we introduce the notion of width in dimension > s for Artinian modules and give a finiteness result for attached primes of certain Tor-modules.
On the Dual Notion of Prime Submodules
Authors: Ansari-Toroghy H. , Farshadifar F.
Published: February 2014

Let R be a commutative ring and M an R-module. In this paper, we study the dual notion of prime submodules (that is, second submodules of M) and investigate the conditions under which the number of maximal second submodules of M is finite. Furthermore, we introduce the concept of coisolated submodules of M and obtain some related characterizations.
Geometry of Alternate Matrices over Bezout Domains
Authors: Huang Liping , Li Yingchun , Zhao Kang
Published: February 2014

Let R be a commutative Bezout domain. Denote by [Formula: see text] the set of all n × n alternate matrices over R. This paper discusses the adjacency preserving bijective maps in both directions on [Formula: see text], and extends Liu's theorem on the geometry of alternate matrices over a field to the case of a Bezout domain.
The Permutable Congruences of bpO-Algebras
Authors: Fang Jie , Sun Zhongju
Published: February 2014

An algebra A is said to be congruence permutable if any two congruences on it are permutable. This property has been investigated in several classes of algebras, for example, de Morgan algebras, p-algebras and MS-algebras, etc. In this paper, we characterize the permutable congruences on a finite Ockham algebra with balanced pseudocomplementation via the Priestley duality.
Finite Groups with Some Subgroups of Given Order
Authors: Shi Jiangtao , Zhang Cui , Liang Dengfeng
Published: February 2014

Let [Formula: see text] be the class of groups of non-prime-power order or the class of groups of prime-power order. In this paper we give a complete classification of finite non-solvable groups with a quite small number of conjugacy classes of [Formula: see text]-subgroups or classes of [Formula: see text]-subgroups of the same order.
Milnor-Witt K-Theory and Tensor Powers of the Augmentation Ideal of ℤ[F×]
Authors: Hutchinson Kevin , Tao Liqun
Published: February 2014

Let F be a field of characteristic not equal to 2. We describe the relation between the non-negative dimensional Milnor-Witt K-theory of F and the tensor algebra over the group ring ℤ[F×] of the augmentation ideal [Formula: see text]. In the process, we clarify the structure of the additive group [Formula: see text], giving a simple presentation in particular.
A Class of Quasitriangular Hopf Group Coalgebras and Drinfel'd Double
Authors: Dong Lihong , Guo Shuangjian , Wang Shuanhong
Published: February 2014

Let G be a group. In this paper we investigate the notion of a quasitriangular Hopf G-coalgebra. We construct a class of smash product Hopf G-coalgebras and present a framework for constructing a quasitriangular Hopf G-coalgebra. As an application, we study an analog of the Drinfel'd double for a crossed Hopf G-coalgebra of finite type.
The 2-Local Ranks of Some Sporadic Groups
Authors: Wang Baoshan
Published: February 2014

In this paper we mainly study sporadic groups in terms of p-local rank, especially, the 2-local ranks of some sporadic groups are given.
Construction of Multi-receiver Multi-fold Authentication Codes from Singular Symplectic Geometry over Finite Fields
Authors: Chen Shangdi , Zhao Dawei
Published: February 2014

As an extension of the basic model of MRA-codes, multi-receiver multi-fold authentication codes can use a single key distribution phase for multiple message transmission. A multi-receiver multi-fold authentication code is constructed from the singular symplectic geometry over finite fields in this paper. The parameters and probabilities of success in impersonation and substitution attacks by malicious groups of receivers of this code are computed.
An assessment of field-portable X-ray fluorescence analysis for nickel and iron in laterite ore (New Caledonia)
Authors: Quiniou Thomas , Laperche Valérie
Published: February 2014

The aim of this work was to determine how
in-situ
portable XRF (pXRF) analysis of ores (in this study, nickel and iron) may be consistent with data obtained from well-prepared samples analysed by conventional XRF methods, and to investigate potential sources of error in field measurements due to different chemical composition, moisture content and particle size. For this study, 201 samples of saprolite and laterite, sieved at 125 μm, were selected for their Ni and Fe contents (from 0.119 to 5.225 % Ni and from 4.7 to 37.2 % Fe for saprolite samples and from 0.38 to 2.94 % Ni and from 21.5 to 55.55 % Fe for laterite samples), compressed to make powder pellets and used to calibrate the pXRF. It is shown that for these two elements, pXRF can correlate extremely well (r
2
> 0.98, relative standard error <7 %) with conventional laboratory results when samples are suitably prepared (dried, pulverized and pelletized). Laboratory analysis of a few artificially wetted samples shows that both Ni and Fe estimated concentrations are directly proportional to moisture content. In the field, two experiments were conducted, one on an air-dried drill-core and the second directly on the pit face. The results indicate that because of sample heterogeneity, Ni and Fe contents are better estimated in the laterite layer than in the saprolite layer. Despite the many challenges associated with field conditions, pXRF can provide useful benefits for a number of applications in the mining sector.
Improving lithological discrimination in exploration drill-cores using portable X-ray fluorescence measurements: (2) applications to the Zn-Cu Matagami mining camp, Canada
Authors: Ross P. -S. , Bourke A. , Fresia B.
Published: February 2014

A new geoscientific application of portable XRF (pXRF) analysers is the acquisition of high-spatial resolution down-hole geochemical profiles obtained
in-situ
on exploration drill-cores. One advantage of such profiles over traditional laboratory geochemistry, apart from the non-destructive aspect of pXRF, is that they are obtained quickly, in the field. So they can help exploration companies take important decisions such as “has a target stratigraphic horizon been reached, or should we drill deeper?” For example, in the Matagami mining camp, pXRF data permits the rapid distinction of two visually similar and variably altered rhyolites in the Persévérance area, based on a plot of Ti/Zr vs Al/Zr. The corrected pXRF data plot within the same fields as the traditional geochemical analyses for these rhyolites. Another advantage of pXRF profiles for exploration companies, geological surveys or academic researchers is the ability to locate lithological contacts better, and in general improve down-hole lithological discrimination, especially for fine-grained and/or hydrothermally altered lithologies. For example, in the Caber volcanogenic massive sulphide deposit area, there are abundant intrusions which makes it difficult to follow the volcanic stratigraphy between drill-holes and sections. In the drill-hole studied, the pXRF data, plotted as down-hole profiles of elements/oxides and ratios, allow several previously unidentified altered dykes to be distinguished from altered rhyolites.
Performance comparison of portable XRF instruments
Authors: Brand N. W. , Brand C. J.
Published: February 2014

Portable XRF instruments are effective tools to provide ‘fit for purpose’ qualitative chemical data that are precise but typically very inaccurate. Under standardized test conditions, the analytical performance of portable XRF instruments varies significantly between individual instruments from the same manufacturer, and between manufacturers using similar instruments. The precision of the instruments to repeat a constant element concentration from a single sample is typically very good (<5 % RSD); however, the accuracy is generally poor to very poor with huge concentration differences in some elements. For example, Al measured from the same NIST standard reference material (NIST 2709a, an agricultural soil) by six Olympus-Innov-X Delta Premium instruments ranged from 2.56 to 7.93 % Al whilst two Thermo-Niton XL3t GOLD+ instruments gave values of 2.14 and 2.33 % Al against the certified value of 7.37 % Al.

After two to five months, repeat analysis by the same instruments under the same conditions shows a measurable deterioration in element concentration, with elements of lower atomic number, Al and Si, the worst affected; for example, the Si response from the Olympus-Innov-X Delta Premium and Thermo-Niton XL3t GOLDD+ instruments deteriorated up to 43 % and 40 %, respectively. This deterioration in the instruments’ performance was observed in all instruments evaluated.

Lithium-ion battery packs, a key to the instruments’ portability, can have a measurable effect on the precision and accuracy of the data with an instant 0.05 % concentration change in Fe (from 3.39 to 3.44 % Fe) during a routine battery pack change. Batteries’ serial numbers should be recorded to monitor these effects and corrections applied.

Each instrument provides uniquely individual data that should not be combined with data from any other units without appropriate post-processing or recalibration. To significantly improve the quality and value of the pXRF data, a calibration procedure appropriate to the material(s) being evaluated should be implemented with regular baseline data collected to ensure instrument and data stability. Over time, matrix calibrations need to be verified with the instrument undergoing a manufacturer’s recalibration when control limits deteriorate significantly.
Calibration of a portable X-ray fluorescence spectrometer in the analysis of archaeological samples using influence coefficients
Authors: Conrey R. M. , Goodman-Elgar M. , Bettencourt N. , Seyfarth A. , Van Hoose A. , Wolff J. A.
Published: February 2014

This paper responds to the expanding interest in archaeology in the use of portable X-Ray fluorescence (pXRF) technologies. Accurate analysis using pXRF requires correction for absorbance and secondary enhancement of the excited element X-rays by the other elements present. Several correction methods are widely used, including fundamental parameters, influence coefficients, Compton ratioing, multi-variate statistical analysis, and dilution. Most pXRF calibrations use either fundamental parameters or multi-variate statistics. However, influence coefficients are known to be the most certain calibration method for XRF analysis of geological materials. Portable XRF calibrations using influence coefficients in the analysis of obsidian, flint, mudbrick, and sediment have far less bias and include a wider range of elements (Mg through Ce) than multi-variate statistical or fundamental parameter calibrations using beam filtered spectra. Bias v. wavelength dispersive XRF data using influence coefficients is mostly less than 1 % for obsidian and flint, and less than 2 % for mudbrick and sediment, in contrast with the large biases (up to 36 %) found using fundamental parameters or multi-variate statistical methods.
Differential regulation of DNA methylation versus histone acetylation in cardiomyocytes during HHcy in vitro and in vivo: an epigenetic mechanism
Authors: Chaturvedi Pankaj , Kalani Anuradha , Givvimani Srikanth , Kamat Pradip Kumar , Familtseva Anastasia , Tyagi Suresh C.
Published: February 2014

The mechanisms of homocysteine-mediated cardiac threats are poorly understood. Homocysteine, being the precursor to S-adenosyl methionine (a methyl donor) through methionine, is indirectly involved in methylation phenomena for DNA, RNA, and protein. We reported previously that cardiac-specific deletion of N-methyl-d-aspartate receptor-1 (NMDAR1) ameliorates homocysteine-posed cardiac threats, and in this study, we aim to explore the role of NMDAR1 in epigenetic mechanisms of heart failure, using cardiomyocytes during hyperhomocysteinemia (HHcy). High homocysteine levels activate NMDAR1, which consequently leads to abnormal DNA methylation vs. histone acetylation through modulation of DNA methyltransferase 1 (DNMT1), HDAC1, miRNAs, and MMP9 in cardiomyocytes. HL-1 cardiomyocytes cultured in Claycomb media were treated with 100 μM homocysteine in a dose-dependent manner. NMDAR1 antagonist (MK801) was added in the absence and presence of homocysteine at 10 μM in a dose-dependent manner. The expression of DNMT1, histone deacetylase 1 (HDAC1), NMDAR1, microRNA (miR)-133a, and miR-499 was assessed by real-time PCR as well as Western blotting. Methylation and acetylation levels were determined by checking 5′-methylcytosine DNA methylation and chromatin immunoprecipitation. Hyperhomocysteinemic mouse models (CBS+/−) were used to confirm the results in vivo. In HHcy, the expression of NMDAR1, DNMT1, and matrix metalloproteinase 9 increased with increase in H3K9 acetylation, while HDAC1, miR-133a, and miR-499 decreased in cardiomyocytes. Similar results were obtained in heart tissue of CBS+/− mouse. High homocysteine levels instigate cardiovascular remodeling through NMDAR1, miR-133a, miR-499, and DNMT1. A decrease in HDAC1 and an increase in H3K9 acetylation and DNA methylation are suggestive of chromatin remodeling in HHcy.
Applying Information Hiding in VANETs to Covertly Report Misbehaving Vehicles
Authors: de Fuentes Jose Maria , Blasco Jorge , González-Tablas Ana Isabel , González-Manzano Lorena
Published: February 2014

Vehicular ad hoc networks (VANETs) are a new communication scenario in which vehicles take an active part. Real-time reporting of misbehaving vehicles by surrounding ones is enabled by in-vehicle sensors and VANETs. Thus, sensors allow detecting the misbehavior whereas VANETs allow sending the report to the authority. Nevertheless, these reports should pass unnoticed by the reported driver to avoid his/her potential reprisals. Information hiding techniques could be used to allow vehicles to transmit information covertly. In this work, two mechanisms for vehicle reporting are proposed based on two information hiding techniques— subliminal channels and steganography. The approach is to embed information into beacon messages either in the signature process (subliminal channel) or altering the least significant bits of selected sensorial fields (steganography). Results show that the proposal is computationally feasible for current vehicular devices and that it is possible to configure the system to operate in highways, secondary roads, and urban maps.
Mesenchymal Stem Cells Expressing Brain-Derived Neurotrophic Factor Enhance Endogenous Neurogenesis in an Ischemic Stroke Model
Authors: Jeong Chang Hyun , Kim Seong Muk , Lim Jung Yeon , Ryu Chung Heon , Jun Jin Ae , Jeun Sin-Soo
Published: February 2014

Numerous studies have reported that mesenchymal stem cells (MSCs) can ameliorate neurological deficits in ischemic stroke models. Among the various hypotheses that have been suggested to explain the therapeutic mechanism underlying these observations, neurogenesis is thought to be critical. To enhance the therapeutic benefits of human bone marrow-derived MSCs (hBM-MSCs), we efficiently modified hBM-MSCs by introduction of the brain-derived neurotrophic factor (BDNF) gene via adenoviral transduction mediated by cell-permeable peptides and investigated whetherBDNF-modified hBM-MSCs (MSCs-BDNF) contributed to functional recovery and endogenous neurogenesis in a rat model of middle cerebral artery occlusion (MCAO). Transplantation of MSCs induced the proliferation of 5-bromo-2′-deoxyuridine (BrdU-) positive cells in the subventricular zone. Transplantation of MSCs-BDNF enhanced the proliferation of endogenous neural stem cells more significantly, while suppressing cell death. Newborn cells differentiated into doublecortin (DCX-) positive neuroblasts and Neuronal Nuclei (NeuN-) positive mature neurons in the subventricular zone and ischemic boundary at higher rates in animals with MSCs-BDNF compared with treatment using solely phosphate buffered saline (PBS) or MSCs. Triphenyltetrazolium chloride staining and behavioral analysis revealed greater functional recovery in animals with MSCs-BDNF compared with the other groups. MSCs-BDNF exhibited effective therapeutic potential by protecting cell from apoptotic death and enhancing endogenous neurogenesis.
Development of Activated Carbon from Cotton Fibre Waste as Potential Mercury Adsorbent: Kinetic and Equilibrium Studies
Authors: Bhakta Jatindra N. , Bhakta Majumdar Piyali , Munekage Yukihiro
Published: February 2014

The study attempted to develop the activated carbon of cotton fibre (ACCF) from cotton waste as a high Hg2+adsorbent media and characterize physicochemical properties using scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) and Hg2+adsorption kinetic by batch adsorption study with the function of contact time, solution pH, dosages of ACCF, and Hg concentration. The SEM-EDS study revealed that ACCF is composed of carbon (95.1%) and phosphorus pentoxide (4.9%). Obtained results of adsorption kinetics showed that 15 min of contact time is required to achieve the equilibrium state and wide range of pH (4.08–7) is favourable for maximum Hg adsorption. The Hg2+adsorption capacity showed a decreasing trend with increasing dose of ACCF, whereas a reverse response of adsorption capacity was pronounced with increasing Hg concentration. The data was well described by Freundlich isotherm model and determined the high Hg2+adsorption capacity of ACCF (169.2 mg/g). To our knowledge, the application of ACCF in removing Hg2+is the first study. High Hg2+adsorption capacity, economic feasibility, availability of cotton fibre waste, and simple preparation method concluded that it could be used as a novel low-cost and environmentally sound adsorbent media for removing high rate of Hg2+from aqueous phase.
Fungal Malignant Otitis Externa with Facial Nerve Palsy: Tissue Biopsy Aids Diagnosis
Authors: Walton Jenny , Coulson Chris
Published: February 2014

Fungal malignant otitis externa (FMOE) is a serious and potentially life-threatening condition that is challenging to manage. Diagnosis is often delayed due to the low sensitivity of aural swabs and many antifungal drugs have significant side effects. We present a case of FMOE, where formal tissue sampling revealed the diagnosis and the patient was successfully treated with voriconazole, in addition to an up to date review of the current literature. We would recommend tissue biopsy of the external auditory canal in all patients with suspected FMOE in addition to routine microbiology swabs.
Observing and Reducing IFUs: INTEGRAL and PMAS—Properties of the Ionized Gas in HH 202
Authors: López-Martín Luis
Published: February 2014

The reduction of integral field spectroscopy (IFS) data requires several stages and many repetitive operations to convert raw data into, typically, a large number of spectra. Instead there are several semiautomatic data reduction tools and here we present this data reduction process using some of the Image Reduction and Analysis Facility (IRAF) tasks devoted to reduce spectroscopic data. After explaining the whole process, we illustrate the power of this instrumental technique with some results obtained for the object HH202 in the Orion Nebula (Mesa-Delgado et al., 2009).
A Validated Method for the Quantitation of Ciprofloxacin Hydrochloride Using Diffuse Reflectance Infrared Fourier Transform Spectroscopy
Authors: Bhongade Bhoomendra , Talath Sirajunisa , Dhaneshwar Sunil
Published: February 2014

A quantitative method using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was developed and validated for the estimation of ciprofloxacin in its tablet dosage forms. The solid-state samples were prepared by dilution in dry potassium bromide and were analyzed by FTIR spectrophotometer with DRIFT sampling technique. A linear relationship for the carbonyl peak area centered around 1709 cm−1 was observed in the range of 0.3–1.5% w/w with good correlation coefficient of 0.998. The percent recovery of ciprofloxacin in three marketed tablet dosage forms was in the range of 98.76 ± 0.27. The present reported method is precise, reproducible, and eco-friendly. DRIFTS may have a potential as an alternative method for qualitative and quantitative analysis of ciprofloxacin in bulk drugs and tablet dosage forms.
Large Eddy Simulation of Supersonic Boundary Layer Transition over a Flat-Plate Based on the Spatial Mode
Authors: Wang Suozhu , Gao Zhenxun , Lee Chunhian , Lei Juanmian
Published: February 2014

The large eddy simulation (LES) of spatially evolving supersonic boundary layer transition over a flat-plate with freestream Mach number 4.5 is performed in the present work. The Favre-filtered Navier-Stokes equations are used to simulate large scales, while a dynamic mixed subgrid-scale (SGS) model is used to simulate subgrid stress. The convective terms are discretized with a fifth-order upwind compact difference scheme, while a sixth-order symmetric compact difference scheme is employed for the diffusive terms. The basic mean flow is obtained from the similarity solution of the compressible laminar boundary layer. In order to ensure the transition from the initial laminar flow to fully developed turbulence, a pair of oblique first-mode perturbation is imposed on the inflow boundary. The whole process of the spatial transition is obtained from the simulation. Through the space-time average, the variations of typical statistical quantities are analyzed. It is found that the distributions of turbulent Mach number, root-mean-square (rms) fluctuation quantities, and Reynolds stresses along the wall-normal direction at different streamwise locations exhibit self-similarity in fully developed turbulent region. Finally, the onset and development of large-scale coherent structures through the transition process are depicted.
Assessment of Haar Wavelet-Quasilinearization Technique in Heat Convection-Radiation Equations
Authors: Saeed Umer , Rehman Mujeeb ur
Published: February 2014

We showed that solutions by the Haar wavelet-quasilinearization technique for the two problems, namely, (i) temperature distribution equation in lumped system of combined convection-radiation in a slab made of materials with variable thermal conductivity and (ii) cooling of a lumped system by combined convection and radiation are strongly reliable and also more accurate than the other numerical methods and are in good agreement with exact solution. According to the Haar wavelet-quasilinearization technique, we convert the nonlinear heat transfer equation to linear discretized equation with the help of quasilinearization technique and apply the Haar wavelet method at each iteration of quasilinearization technique to get the solution. The main aim of present work is to show the reliability of the Haar wavelet-quasilinearization technique for heat transfer equations.
Late Presentation of Unsafe Abortion after 5 Years of Procedure
Authors: Nayak Prasanta Kumar , Mitra Subarna , Padma Alaganandam , Agrawal Sarita
Published: February 2014

A majority of the unsafe abortions are performed by untrained birth attendants or quacks leading to complications in a large proportion of these cases. Complications like bowel injury, bladder injury, uterine perforation, and septic abortion are mostly caused by unskilled hands and are detected immediately or within few days of the procedure, owing to the need for tertiary level care. Here we present a very interesting case of unsafe abortion induced by a Ryle’s tube in a 32-year-old lady, which was diagnosed five years after the procedure. Considering its atypical presentation, it is the first case of its kind in the literature. The details of the case and its management are described along with appropriate pictures.