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On the Symmetric Homology of AlgebrasAult, Shaun V. 11 September 2008 (has links)
No description available.
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Gradient idealsLiu, Yu-Han 28 September 2010 (has links)
No description available.
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Determiner removal in Balinese nonpivot agentsDriemel, Imke, Tebay, Sören E. 05 January 2024 (has links)
Patient-voice clauses within the symmetric voice system
of Balinese disallow any extraction from the
external-argument position, while definite external
arguments are blocked from occurring altogether. The
former fact is traditionally taken as evidence for syntactic
ergativity in Austronesian. The latter fact has
recently been argued to provide evidence for postsyntactic
case licensing via adjacency with the verb. In
this article, we offer a simple alternative explanation
for the in-situ properties of patient-voice agents in
Balinese—one that does not make reference to case.We
argue that patient-voice heads come with a feature that
triggers removal of the external argument’s DP shell,
resulting in the loss of a determiner and a category-D
feature that would otherwise enable extraction.
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Yangian symmetric correlators, R operators and amplitudesKirschner, Roland 09 August 2022 (has links)
Yangian symmetric correlators can be constructed by the action of Yang-Baxter
R operators on trivial basic correlators. The example of a four-point correlator is given in two
representations and the construction of the completely connected N point correlator is described.
The helicity representation is dicussed and the relation of the four-point correlator to tree-level
scattering amplitudes is shown.
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Well-posedness results for a class of complex flow problems in the high Weissenberg number limitWang, Xiaojun 22 May 2012 (has links)
For simple fluids, or Newtonian fluids, the study of the Navier-Stokes equations in the high Reynolds number limit brings about two fundamental research subjects, the Euler equations and the Prandtl's system. The consideration of infinite Reynolds number reduces the Navier-Stokes equations to the Euler equations, both of which are dealing with the entire flow region. Prandtl's system consists of the governing equations of the boundary layer, a thin layer formed at the wall boundary where viscosity cannot be neglected.
In this dissertation, we investigate the upper convected Maxwell(UCM) model for complex fluids, or non-Newtonian fluids, in the high Weissenberg number limit. This is analogous to the Newtonian fluids in the high Reynolds number limit. We present two well-posedness results.
The first result is on an initial-boundary value problem for incompressible hypoelastic materials which arise as a high Weissenberg number limit of viscoelastic fluids. We first assume the stress tensor is rank-one and develop energy estimates to show the problem is locally well-posed. Then we show the more general case can be handled in the same spirit. This problem is closely related to the incompressible ideal magneto-hydrodynamics (MHD) system.
The second result addresses the formulation of a time-dependent elastic boundary layer through scaling analysis. We show the well-posedness of this boundary layer by transforming to Lagrangian coordinates. In contrast to the possible ill-posedness of Prandtl's system in Newtonian fluids, we prove that in non-Newtonian fluids the stress boundary layer problem is well-posed. / Ph. D.
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Properties degradation induced by transverse cracks in general symmetric laminatesZhang, D., Ye, J., Lam, Dennis January 2007 (has links)
No / This paper presents the details of a methodology for predicting the thermoelastic properties degradation in general symmetric laminates with uniform ply cracks in some or all of the 90° layers. First, a stress transfer method is derived by using the concept of state space equation. The laminate can be subjected to any combination of in-plane biaxial and shear loading, and the uniform thermal loading is also taken into account. The method takes into account all independent material constants and guarantees continuous fields of all interlaminar stresses across interfaces between material layers. By this method, a laminate may be composed of an arbitrary number of monoclinic layers and each layer may have different material property and thickness. Second, the concept of the effective thermoelastic properties of a cracked laminate is introduced. Based on the numerical solutions of specially designed loading cases, the effective thermoelastic constants of a cracked laminate can be obtained. Finally, the applications of the methodology are shown by numerical examples and compared with numerical results from other models and experiment data in the literature. It is found that the theory provides good predictions of the thermoelastic properties degradation in general symmetric laminates.
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Fullerene: biomedical engineers get to revisit an old friendGoodarzi, S., Da Ros, T., Conde, J., Sefat, Farshid, Mozafari, M. 24 April 2017 (has links)
Yes / In 1985, the serendipitous discovery of fullerene triggered the research of carbon structures into the
world of symmetric nanomaterials. Consequently, Robert F. Curl, Harold W. Kroto and Richard E.
Smalley were awarded the Noble prize in chemistry for their discovery of the buckminsterfullerene
(C60 with a cage-like fused-ring structure). Fullerene, as the first symmetric nanostructure in carbon
nanomaterials family, opened up new perspectives in nanomaterials field leading to discovery and
research on other symmetric carbon nanomaterials like carbon nanotubes and two-dimensional
graphene which put fullerenes in the shade, while fullerene as the most symmetrical molecule in the
world with incredible properties deserves more attention in nanomaterials studies. Buckyball with its
unique structure consisting of sp2 carbons which form a high symmetric cage with different sizes
(C60, C70 and so on); however, the most abundant among them is C60 which possesses 60 carbon atoms.
The combination of unique properties of this molecule extends its applications in divergent areas of
science, especially those related to biomedical engineering. This review aims to be a comprehensive
review with a broad interest to the biomedical engineering community, being a substantial overview of
the most recent advances on fullerenes in biomedical applications that have not been exhaustively and
critically reviewed in the past few years.
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Towards The Total Synthesis Of Withanolide E And Physachenolide CAnees, Muhammad January 2020 (has links)
Withanolides are a class of ergostane natural products found in plants of family Solanaceae.
Plants of this family are used in traditional medicine in Asia and South America. Recently, a
series of 17β-hydroxy withanolides were identified from high-throughput screens as
inhibitors of androgen-induced changes in gene expression of prostate cancer cells.
Therefore, these compounds may have important applications as new therapies against
prostate cancer. We have devised a synthetic route to members of this family and their
analogues which allows stereoselective introduction of C14, C17 and C20 hydroxyl groups in
separate steps. This will allow preparation of differentially hydroxylated analogues so as to
identify which contributes to the potency and thus gain a better understanding of the SAR of
this class of bioactive molecules. As part of this we have shown that the stereochemical
outcome of the epoxidation of Δ 14-15 cholestanes with m-CPBA is controlled by the steric bulk
of a C17 substituent. When the C17 is in the β configuration, the epoxide is formed on the α
face, whereas if the C17 is trigonal (flat) or the substituent is in the α configuration, the epoxide is formed on the β face. The presence of a hydroxyl substituent at C20 does not
influence the stereochemical outcome of the epoxidation. We have successfully introduced
aldehyde functionality to the lateral side chain 14 hydroxyl compound. This aldehyde
compound is a key intermediate from which many of the withanolides can be made. We
have also investigated the introduction of a hydroxyl at the C18 as an entry into the
physachenolides. Finally, we have carried out an assessment of the potency of the
synthesised compounds against hormone-insensitive prostate cancer cell line, PC-3.
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Propriedades de Lie de elementos simétricos sob involuções orientadas em álgebras de grupo / Lie properties of symmetric elements under oriented involutions in group algebrasCastillo Gomez, John Hermes 29 November 2012 (has links)
Sejam $F$ um corpo de característica diferente de $2$ e $G$ um grupo. A partir da involução clássica, que envia cada elemento em seu inverso, e uma orientação do grupo $G$ é possível definir uma involução clássica orientada na álgebra de grupo $FG$. O objetivo desta tese é estudar propriedades de Lie do conjunto dos elementos simétricos $(FG)^+$ e, em alguns casos, do conjunto dos elementos anti-simétricos $(FG)^-$. Primeiro, abordamos o caso quando $G$ não tem elementos de ordem $2$. Aqui, mostramos que se $(FG)^+$ (ou $(FG)^-$) é Lie nilpotente ou Lie $n$-Engel, então $FG$ também é Lie nilpotente ou Lie $m$-Engel, respectivamente. Depois, consideramos o caso quando $G$ contém uma cópia do grupo quatérnio de ordem $8$. Neste caso, caracterizamos completamente as álgebras de grupo tais que $(FG)^+$ é fortemente Lie nilpotente, Lie nilpotente e Lie $n$-Engel. Como consequência, provamos que o conjunto das unidades simétricas deste tipo de grupos é nilpotente. Estudamos também o caso em que quando $G$ não contém uma cópia do grupo quatérnio de ordem $8$. Em particular, apresentamos um exemplo que mostra que os resultados obtidos em pesquisas anteriores, com a involução clássica, não devem ser esperados ao trabalhar com involuções clássicas orientadas. Não entanto, damos alguns casos especiais de grupos nos quais esses resultados são obtidos. Finalmente, estudamos o índice de Lie nilpotência de $(FG)^+$. Estabelecemos uma condição necessária e suficiente, para que o índice de Lie nilpotência de $(FG)^+$ e a classe de nilpotência das unidades simétricas de uma álgebra de grupo Lie nilpotente sejam o maior possível. Além disso, consideramos a situação em que o grupo $G$ contém uma cópia de $Q_8$. / Let $F$ be a field of characteristic different from $2$ and $G$ a group. From the classical involution, which sends each element in its inverse and an orientation of $G$, it is possible to define an oriented classical involution on the group algebra $FG$. The goal of this thesis is to study Lie properties of the set of symmetric elements $(FG)^+$ and, in some cases, of the set of skew-symmetric elements $(FG)^-$. We first deal with the case when $G$ does not have elements of order $2$. In this situation, we show that if $(FG)^+$ (or $(FG)^-$) is Lie nilpotent or Lie $n$-Engel, then the whole group algebra $FG$ satisfies the same property. Later we consider the case when $G$ contains a copy of the quaternion group of order $8$. In this instance, we give a complete description of the group algebras such that $(FG)^+$ is strongly Lie nilpotent, Lie nilpotent and Lie $n$-Engel. As a consequence, we get that the set of symmetric units of this kind of groups is nilpotent. Furthermore, we study the case when $G$ does not contain a copy of the quaternion group of order $8$. Here, we present an example that shows that the previews results obtained in former works, with the classical involution, may not hold with an oriented classical involution. However, we give some kinds of groups for which those results are achieved. Finally, we study the Lie nilpotency index of $(FG)^+$. It is given a necessary and sufficient condition to the Lie nilpotency index of $(FG)^+$ and the nilpotency class of the symmetric units to be maximal, in a Lie nilpotent group algebra. In addition, we consider the situation when $G$ contains a copy of the quaternion group of order $8$.
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Propriedades de Lie de elementos simétricos sob involuções orientadas em álgebras de grupo / Lie properties of symmetric elements under oriented involutions in group algebrasJohn Hermes Castillo Gomez 29 November 2012 (has links)
Sejam $F$ um corpo de característica diferente de $2$ e $G$ um grupo. A partir da involução clássica, que envia cada elemento em seu inverso, e uma orientação do grupo $G$ é possível definir uma involução clássica orientada na álgebra de grupo $FG$. O objetivo desta tese é estudar propriedades de Lie do conjunto dos elementos simétricos $(FG)^+$ e, em alguns casos, do conjunto dos elementos anti-simétricos $(FG)^-$. Primeiro, abordamos o caso quando $G$ não tem elementos de ordem $2$. Aqui, mostramos que se $(FG)^+$ (ou $(FG)^-$) é Lie nilpotente ou Lie $n$-Engel, então $FG$ também é Lie nilpotente ou Lie $m$-Engel, respectivamente. Depois, consideramos o caso quando $G$ contém uma cópia do grupo quatérnio de ordem $8$. Neste caso, caracterizamos completamente as álgebras de grupo tais que $(FG)^+$ é fortemente Lie nilpotente, Lie nilpotente e Lie $n$-Engel. Como consequência, provamos que o conjunto das unidades simétricas deste tipo de grupos é nilpotente. Estudamos também o caso em que quando $G$ não contém uma cópia do grupo quatérnio de ordem $8$. Em particular, apresentamos um exemplo que mostra que os resultados obtidos em pesquisas anteriores, com a involução clássica, não devem ser esperados ao trabalhar com involuções clássicas orientadas. Não entanto, damos alguns casos especiais de grupos nos quais esses resultados são obtidos. Finalmente, estudamos o índice de Lie nilpotência de $(FG)^+$. Estabelecemos uma condição necessária e suficiente, para que o índice de Lie nilpotência de $(FG)^+$ e a classe de nilpotência das unidades simétricas de uma álgebra de grupo Lie nilpotente sejam o maior possível. Além disso, consideramos a situação em que o grupo $G$ contém uma cópia de $Q_8$. / Let $F$ be a field of characteristic different from $2$ and $G$ a group. From the classical involution, which sends each element in its inverse and an orientation of $G$, it is possible to define an oriented classical involution on the group algebra $FG$. The goal of this thesis is to study Lie properties of the set of symmetric elements $(FG)^+$ and, in some cases, of the set of skew-symmetric elements $(FG)^-$. We first deal with the case when $G$ does not have elements of order $2$. In this situation, we show that if $(FG)^+$ (or $(FG)^-$) is Lie nilpotent or Lie $n$-Engel, then the whole group algebra $FG$ satisfies the same property. Later we consider the case when $G$ contains a copy of the quaternion group of order $8$. In this instance, we give a complete description of the group algebras such that $(FG)^+$ is strongly Lie nilpotent, Lie nilpotent and Lie $n$-Engel. As a consequence, we get that the set of symmetric units of this kind of groups is nilpotent. Furthermore, we study the case when $G$ does not contain a copy of the quaternion group of order $8$. Here, we present an example that shows that the previews results obtained in former works, with the classical involution, may not hold with an oriented classical involution. However, we give some kinds of groups for which those results are achieved. Finally, we study the Lie nilpotency index of $(FG)^+$. It is given a necessary and sufficient condition to the Lie nilpotency index of $(FG)^+$ and the nilpotency class of the symmetric units to be maximal, in a Lie nilpotent group algebra. In addition, we consider the situation when $G$ contains a copy of the quaternion group of order $8$.
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