Absence of sign problem in two-dimensional N=(2,2) super Yang-Mills on lattice

We show that N=(2,2) SU(N) super Yang-Mills theory on lattice does not have sign problem in the continuum limit, that is, under the phase-quenched simulation phase of the determinant localizes to 1 and hence the phase-quench approximation becomes exact. Among several formulations, we study models by Cohen-Kaplan-Katz-Unsal (CKKU) and by Sugino. We confirm that the sign problem is absent in both models and that they converge to the identical continuum limit without fine tuning. We provide a simple explanation why previous works by other authors, which claim an existence of the sign problem, do not capture the continuum physics.Comment: 27 pages, 24 figures; v2: comments and references added; v3: figures on U(1) mass independence and references added, to appear in JHE

An anisotropic hybrid non-perturbative formulation for 4D N = 2 supersymmetric Yang-Mills theories

We provide a simple non-perturbative formulation for non-commutative four-dimensional N = 2 supersymmetric Yang-Mills theories. The formulation is constructed by a combination of deconstruction (orbifold projection), momentum cut-off and matrix model techniques. We also propose a moduli fixing term that preserves lattice supersymmetry on the deconstruction formulation. Although the analogous formulation for four-dimensional N = 2 supersymmetric Yang-Mills theories is proposed also in Nucl.Phys.B857(2012), our action is simpler and better suited for computer simulations. Moreover, not only for the non-commutative theories, our formulation has a potential to be a non-perturbative tool also for the commutative four-dimensional N = 2 supersymmetric Yang-Mills theories.Comment: 32 pages, final version accepted in JHE

Numerical studies of the ABJM theory for arbitrary N at arbitrary coupling constant

We show that the ABJM theory, which is an N=6 superconformal U(N)*U(N) Chern-Simons gauge theory, can be studied for arbitrary N at arbitrary coupling constant by applying a simple Monte Carlo method to the matrix model that can be derived from the theory by using the localization technique. This opens up the possibility of probing the quantum aspects of M-theory and testing the AdS_4/CFT_3 duality at the quantum level. Here we calculate the free energy, and confirm the N^{3/2} scaling in the M-theory limit predicted from the gravity side. We also find that our results nicely interpolate the analytical formulae proposed previously in the M-theory and type IIA regimes. Furthermore, we show that some results obtained by the Fermi gas approach can be clearly understood from the constant map contribution obtained by the genus expansion. The method can be easily generalized to the calculations of BPS operators and to other theories that reduce to matrix models.Comment: 35 pages, 20 figures; reference added. The simulation code is available upon request to [email protected]

ITS (Intergenic Transcribed Spacer) e Íntron-RFLP para caracterização de Colletotrichum spp. isolado de guaranazeiro.

O objetivo do trabalho foi utilizar as regiões ITS e o íntron do gene GS (Glutamine Synthetase) na caracterização de Colletotrichum spp., obtidos a partir de isolamento direto das lesões foliares típicas de antracnose em guaranazeiro

Direct test of the gauge-gravity correspondence for Matrix theory correlation functions

We study correlation functions in (0+1)-dimensional maximally supersymmetric U(N) Yang-Mills theory, which was proposed by Banks et al. as a non-perturbative definition of 11-dimensional M-theory in the infinite-momentum frame. We perform first-principle calculations using Monte Carlo simulations, and compare the results against the predictions obtained previously based on the gauge-gravity correspondence from 10 dimensions. After providing a self-contained review on these predictions, we present clear evidence that the predictions in the large-N limit actually hold even at small N such as N=2 and 3. The predicted behavior seems to continue to the far infrared regime, which goes beyond the naive range of validity of the 10D supergravity analysis. This suggests that the correlation functions also contain important information on the M-theory limit.Comment: v1: 43 pages, 16 figures. v2, v3: minor correction

Construction of gateway binary vector for selection with bialaphos or carboxin and GFP expression in fungi.

Genomic data has created a growing demand for tools and methodologies for studying the genes function, which can be realized through loss of function experiments (gene knockout) or by RNA silencing (knockdown). The develop-ment of binary vectors for Agrobacterium tumefaciens mediated transformation (ATMT) has the advantage of being independent of protoplast formation and can be used directly on a wide variety of fungal species and tissue types. The selection of transformants using bialaphos and carboxin has the advantages of low cost in the transformation and availability of different selectable markers, also allowing the analysis of several genes and combination of study by knockout or knockdown, using selectable markers in the same transformant. Thus, this study aimed to build two binary vectors containing reporter gene and selectable markers that confer resistance to carboxin and bialaphos. The cassettes were constructed using the Gateway system to two fragments. The gene encoding the GFP protein and PtoxA and PtrpCpromoters were cloned into pDONR P1-P5R plasmid. Genes that confer bialaphos and carboxin resistance, bar and cbxr respectively, were cloned into pDONR P5-P2 plasmid. The pPGW plasmid was used as des-tination vector. The gfp gene transcription is controlled by PtoxA promoter and the bar and cbxr genes transcriptions are controlled by PtrpC promoter. These binary vectors were named pGWGFP-BAR and pGWGFP-CBXR. The assembly of cassettes was confi rmed by sequencing, and the validation of vectors is being accomplished through transformation (ATMT) with the plant pathogens Mycosphaerella fi jiensis and Fusarium oxysporum f. sp. cubense

11 beta-hydroxysteroid dehydrogenase type 1 regulates glucocorticoid-induced insulin resistance in skeletal muscle

OBJECTIVE: Glucocorticoid excess is characterized by increased adiposity, skeletal myopathy, and insulin resistance, but the precise molecular mechanisms are unknown. Within skeletal muscle, 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) converts cortisone (11-dehydrocorticosterone in rodents) to active cortisol (corticosterone in rodents). We aimed to determine the mechanisms underpinning glucocorticoid-induced insulin resistance in skeletal muscle and indentify how 11beta-HSD1 inhibitors improve insulin sensitivity. \ud RESEARCH DESIGN AND METHODS: Rodent and human cell cultures, whole-tissue explants, and animal models were used to determine the impact of glucocorticoids and selective 11beta-HSD1 inhibition upon insulin signaling and action. \ud RESULTS: Dexamethasone decreased insulin-stimulated glucose uptake, decreased IRS1 mRNA and protein expression, and increased inactivating pSer$^{307}$ insulin receptor substrate (IRS)-1. 11beta-HSD1 activity and expression were observed in human and rodent myotubes and muscle explants. Activity was predominantly oxo-reductase, generating active glucocorticoid. A1 (selective 11beta-HSD1 inhibitor) abolished enzyme activity and blocked the increase in pSer$^{307}$ IRS1 and reduction in total IRS1 protein after treatment with 11DHC but not corticosterone. In C57Bl6/J mice, the selective 11beta-HSD1 inhibitor, A2, decreased fasting blood glucose levels and improved insulin sensitivity. In KK mice treated with A2, skeletal muscle pSer$^{307}$ IRS1 decreased and pThr$^{308}$ Akt/PKB increased. In addition, A2 decreased both lipogenic and lipolytic gene expression.\ud CONCLUSIONS: Prereceptor facilitation of glucocorticoid action via 11beta-HSD1 increases pSer$^{307}$ IRS1 and may be crucial in mediating insulin resistance in skeletal muscle. Selective 11beta-HSD1 inhibition decreases pSer$^{307}$ IRS1, increases pThr$^{308}$ Akt/PKB, and decreases lipogenic and lipolytic gene expression that may represent an important mechanism underpinning their insulin-sensitizing action

Using BOX and ERIC-PCR to differentiate Fusarium decemcellulare isolated from guarana plant.

Resumo:649-2

Variabilidade genética de Fusarium decemcellulare isolado de três diferentes sintomas em guaranazeiro (Paullinia cupana var. sorbilis).

O objetivo deste trabalho foi analisar a variabilidade entre isolados obtidos de diferentes genótipos de guaranazeiro e de diferentes sintomas.Resumo:57-2

Correction due to finite speed of light in absolute gravimeters

Correction due to finite speed of light is among the most inconsistent ones in absolute gravimetry. Formulas reported by different authors yield corrections scattered up to 8 $\mu$Gal with no obvious reasons. The problem, though noted before, has never been studied, and nowadays the correction is rather postulated than rigorously proven. In this paper we make an attempt to revise the subject. Like other authors, we use physical models based on signal delays and the Doppler effect, however, in implementing the models we additionally introduce two scales of time associated with moving and resting reflectors, derive a set of rules to switch between the scales, and establish the equivalence of trajectory distortions as obtained from either time delay or distance progression. The obtained results enabled us to produce accurate correction formulas for different types of instruments, and to explain the differences in the results obtained by other authors. We found that the correction derived from the Doppler effect is accountable only for $\frac23$ of the total correction due to finite speed of light, if no signal delays are considered. Another major source of inconsistency was found in the tacit use of simplified trajectory models