We present a group theoretic construction of the Virasoro algebra in the framework of wreath products. This can be regarded as a counterpart of a geometric construction of Lehn in the theory of Hilbert schemes of points on a surface. Introduction It is by now well known that a direct sum ⊕ n≥0R(Sn) of the Grothendieck rings of symmetric groups Sn can be identified with the Fock space of the Hei...

After introducing double derivations of $n$-Lie algebra $L$ we‎ ‎describe the relationship between the algebra $mathcal D(L)$ of double derivations and the usual‎ ‎derivation Lie algebra $mathcal Der(L)$‎. ‎In particular‎, ‎we prove that the inner derivation algebra $ad(L)$‎ ‎is an ideal of the double derivation algebra $mathcal D(L)$; we also show that if $L$ is a perfect $n$-Lie algebra‎ ‎wit...

To provide detachable, secure and long-term stable joints in fused-layer modelling (FLM) components or assemblies, metal threaded inserts are widely used as extrinsic interfaces. However, the load-bearing capacity of such is influenced by inhomogeneous, anisotropic material structure FLM components. This work evaluates influence joining zone design printing process parameters on achievable join...

Additively manufactured parts play an increasingly important role in structural applications. Fused Layer Modeling (FLM) has gained popularity due to its cost-efficiency and broad choice of materials, among them, short fibre reinforced filaments with high specific stiffness strength. To design functional FLM parts, adequate material models for simulations are crucial, as these allow reliable si...

let a be a banach algebra and e be a banach a-bimodule then s = a  e, the l1-direct sum of a and e becomes a module extension banach algebra when equipped with the algebras product (a; x):(a′; x′) = (aa′; a:x′ + x:a′). in this paper, we investigate △-amenability for these banach algebras and we show that for discrete inverse semigroup s with the set of idempotents es, the module extension bana...

Here Welita Caetano, an organizer with the Front for Struggle Housing (FLM) in São Paulo, Brazil, writes about her own experiences as a homeless person, leader of housing movement, popular educator, and municipal counselor. As she explains, occupations justice are small revolutions means building relationships community.

Leukocyte [white blood cell (WBC)] adhesion and shedding of glycans from the endothelium [endothelial cells (ECs)] in response to the chemoattractant f-Met-Leu-Phe (fMLP) has been shown to be attenuated by topical inhibition of matrix metalloproteases (MMPs) with doxycycline (Doxy). Since Doxy also chelates divalent cations, these responses were studied to elucidate the relative roles of cation...

It is shown that a massless scalar probe reveals a universal near-horizon conformal structure for a wide class of black holes, including the BTZ. The central charge of the corresponding Virasoro algebra contains information about the black hole. With a suitable quantization condition on the central charge, the CFT associated with the black hole in our approach is consistent with the recent obse...

⎯ To enable formation flying of micro satellites, small sized propulsion systems are required. Our research focuses on the miniaturization of a feeding and thruster system by means of micro system technology (MST). Three fabrication methods have been investigated to make a conical converging-diverging nozzle. These methods are reactive ion etching, femtosecond laser machining (FLM) and a combin...