988 resultados para dilute Temperley-Lieb algebra
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This paper introduces the metaphorism pattern of relational specification and addresses how specification following this pattern can be refined into recursive programs. Metaphorisms express input-output relationships which preserve relevant information while at the same time some intended optimization takes place. Text processing, sorting, representation changers, etc., are examples of metaphorisms. The kind of metaphorism refinement proposed in this paper is a strategy known as change of virtual data structure. It gives sufficient conditions for such implementations to be calculated using relation algebra and illustrates the strategy with the derivation of quicksort as example.
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We consider implicit signatures over finite semigroups determined by sets of pseudonatural numbers. We prove that, under relatively simple hypotheses on a pseudovariety V of semigroups, the finitely generated free algebra for the largest such signature is closed under taking factors within the free pro-V semigroup on the same set of generators. Furthermore, we show that the natural analogue of the Pin-Reutenauer descriptive procedure for the closure of a rational language in the free group with respect to the profinite topology holds for the pseudovariety of all finite semigroups. As an application, we establish that a pseudovariety enjoys this property if and only if it is full.
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OBJECTIVE: Lupus anticoagulant and anticardiolipin antibodies (aCL) have been associated with thrombosis, recurrent abortion, and thrombocytopenia in patients with systemic lupus erythematosus (SLE), but their relationship with cardiac disease is less clear. The purpose of this study was to evaluate the association between antiphospholipid antibodies (aPL) and echocardiographic abnormalities in patients with SLE. METHODS: A total of 70 consecutive patients and 42 control subjects underwent M-mode, 2-dimensional and Doppler echocardiography and tests for lupus anticoagulant, aCL IgG, IgM, and IgA. Lupus anticoagulant was assayed with the dilute Russell viper venom time, and aCL IgG, IgM, and IgA were measured by an enzyme-linked immunosorbent assay (ELISA). RESULTS: Lupus anticoagulant showed a prevalence of 10%. As a whole, aCL had a prevalence of 44.3% and aPL had a prevalence of 50%. Patients with echocardiographic abnormalities had a prevalence of 54.3% and showed a trend towards an association with aCL IgG (P=0.06). The presence of pulmonary hypertension (PH) was significantly associated with aCL IgG (p=0.02). CONCLUSION: aCL IgG was significantly associated with PH and showed a strong trend towards an association with echocardiographic abnormalities taken together. These findings suggest a role for aCL IgG in the development of lupus cardiovascular disease.
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Em uma zona cristalográfica podem ocorrer símbolos de faces, cujos índices de Miller, colocados em determinada ordem, formam aquilo que, em algebra, se conhece sob a designação de "série harmônica". Este trabalho mostra como tal possibilidade pode ser pesquisada.
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Aus: CrystEngComm, Vol. 17.2015, H. 2, S. 331-337
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Two sweet sorghum varieties, Brandes and Rio, were grown in full strenght and diluted nutrient solutions till completing the life cycle wherein mineral analyses were carried out. As a rule both varieties showed the same capacity to absorb nutrients in the two rates supplied. Dry matter yield, however was different in the dilute nutrient solution. The variety Brandes produced more fresh stalks in the full strength solution than Rio; under nutricional stress the yield was lower. Dry matter of stalks in the case of the variety Rio was consistently higher.
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I) the A. presents a method developed for the preparation of thick blood films, specially old desiccated smears. The observations are based on the experience of more than 53000 blood samples collected in the laboratory of the Serviço de Malaria do Nordeste as well as in the research department of the Serviço de Malaria da Baixada Fluminenese. II) As in introductory matter, he emphasizes the value of the obstacles presented by overdrying of the thick blood films occurring systematically in great malaria control organizations in which the laboratory receives materials from more or less remote localities, particularly in the Brazilian northeast, in regions invaded by Anopheles gambiae. III) An analysis of the causes of failure of the methods of Chorine and Knowles recorded in the literature for such purposes is given, as well as its adaptability for the simultaneous preparation of large numbers of samples. IV) The method is based the protective action of a previous fixation by a dilute solution of formalin, which, without preventing further dehemoglobinization, prevents morphological alterations in the parasites by the action of Knowles solution which is retained in this metod without modification. V) For washing out the acids of the dehemoglobinizating solution as well as for diluting the Giemsa stain, the A. proposes a very simple technique, extremely convenient for such purpose, which consists in adding acetic acid to the distilled water in the proportion of 1 drop for each 10cc of water, and then increasing the hydrogeni-on concentration to pH 7.2 with a 2% sol. of sodium carbonate. As indicator a 0.02% solution purple-bromcresol prepared in accordante to Medalia, is used. In this reaction there is the formation of the acetic acid ↔ sodium acetate, buffer system very suitable for giving a convenient pH and for preventing the precipitation of the dye, which can be used for two or three batches of 700 or 800 slides each, without changing the staining solution. VI) The method can be summarized as follow: For a small number of samples, Coplins or any other staining jar can be used. Large number of slides must be placed in groups of 10 or 15 units each, the slides being separated by a piece of cardboard, according to Barber & Komp. A) Fix in dilute formalin (2%), during 5 minutes. b) Without washing, put in Knowles solution (see the formula in the text), no more than 20 minutes. c)Two successive washings in distilled water, buffered as explained above (which can be used several times). d) Dry and stain with Giemsa solution, prepared by using 1 drop of the stain for each c. c. of buffered distilled water. Time: 1 hour. E) Was in distilled water and dry.
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Let A be a simple, unital, finite, and exact C*-algebra which absorbs the Jiang-Su algebra Z tensorially. We prove that the Cuntz semigroup of A admits a complete order embedding into an ordered semigroup which is obtained from the Elliott invariant in a functorial manner. We conjecture that this embedding is an isomor phism, and prove the conjecture in several cases. In these same cases - Z-stable algebras all - we prove that the Elliott conjecture in its strongest form is equivalent to a conjecture which appears much weaker. Outside the class of Z-stable C*-algebras, this weaker conjecture has no known counterexamples, and it is plausible that none exist. Thus, we reconcile the still intact principle of Elliott's classification conjecture -that K-theoretic invariants will classify separable and nuclear C*-algebras- with the recent appearance of counterexamples to its strongest concrete form.
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The purpose of this short note is to prove that a stable separable C*-algebra with real rank zero has the so-called corona factorization property, that is, all the full multiplier projections are properly in finite. Enroute to our result, we consider conditions under which a real rank zero C*-algebra admits an injection of the compact operators (a question already considered in [21]).
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In this paper, results known about the artinian and noetherian conditions for the Leavitt path algebras of graphs with finitely many vertices are extended to all row-finite graphs. In our first main result, necessary and sufficient conditions on a row-finite graph E are given so that the corresponding (not necessarily unital) Leavitt path K-algebra L(E) is semisimple. These are precisely the algebras L(E)for which every corner is left (equivalently, right)artinian. They are also precisely the algebras L(E) for which every finitely generated left (equivalently, right) L(E)-module is artinian. In our second main result, we give necessary and sufficient conditions for every corner of L(E) to be left (equivalently, right) noetherian. They also turn out to be precisely those algebras L(E) for which every finitely generated left(equivalently, right) L(E)-module is noetherian. In both situations, isomorphisms between these algebras and appropriate direct sums of matrix rings over K or K[x, x−1] are provided. Likewise, in both situations, equivalent graph theoretic conditions on E are presented.
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We prove a double commutant theorem for hereditary subalgebras of a large class of C*-algebras, partially resolving a problem posed by Pedersen[8]. Double commutant theorems originated with von Neumann, whose seminal result evolved into an entire field now called von Neumann algebra theory. Voiculescu proved a C*-algebraic double commutant theorem for separable subalgebras of the Calkin algebra. We prove a similar result for hereditary subalgebras which holds for arbitrary corona C*-algebras. (It is not clear how generally Voiculescu's double commutant theorem holds.)
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Let A be a semiprime 2 and 3-torsion free non-commutative associative algebra. We show that the Lie algebra Der(A) of(associative) derivations of A is strongly non-degenerate, which is a strong form of semiprimeness for Lie algebras, under some additional restrictions on the center of A. This result follows from a description of the quadratic annihilator of a general Lie algebra inside appropriate Lie overalgebras. Similar results are obtained for an associative algebra A with involution and the Lie algebra SDer(A) of involution preserving derivations of A
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We extend the theory of Quillen adjunctions by combining ideas of homotopical algebra and of enriched category theory. Our results describe how the formulas for homotopy colimits of Bousfield and Kan arise from general formulas describing the derived functor of the weighted colimit functor.
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In a recent paper Iyama and Yoshino consider two interesting examples of isolated singularities over which it is possible to classify the indecomposable maximal Cohen-Macaulay modules in terms of linear algebra data. In this paper we present two new approaches to these examples. In the first approach we give a relation with cluster categories. In the second approach we use Orlov's result on the graded singularity category. We obtain some new results on the singularity category of isolated singularities which may be interesting in their own right.
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We show that H-spaces with finitely generated cohomology, as an algebra or as an algebra over the Steenrod algebra, have homotopy exponents at all primes. This provides a positive answer to a question of Stanley.