Conductance peaks in open quantum dots

We present a simple measure of the conductance fluctuations in open ballistic chaotic quantum dots, extending the number of maxima method originally proposed for the statistical analysis of compound nuclear reactions. The average number of extreme points (maxima and minima) in the dimensionless conductance, $T$, as a function of an arbitrary external parameter $Z$, is directly related to the autocorrelation function of $T(Z)$. The parameter $Z$ can be associated to an applied gate voltage causing shape deformation in quantum dot, an external magnetic field, the Fermi energy, etc.. The average density of maxima is found to be $= \alpha_{Z}/Z_c$, where $\alpha_{Z}$ is a universal constant and $Z_c$ is the conductance autocorrelation length, which is system specific. The analysis of $$ does not require large statistic samples, providing a quite amenable way to access information about parametric correlations, such as $Z_c$.Comment: 5 pages, 5 figures, accepted to be published - Physical Review Letter

A estética como ato político : entrevista com Josep Maria Català Domenech

Josep Maria Català Domenech é diretor da Faculdade de Comunicação da Universidade Autônoma de Barcelona (UAB), diretor do Mestrado em Documentário Criativo e professor de Narativa audiovisual e Estética da imagem na mesma instituição. Doutor em Ciências da Comunicação pela UAB e mestre em Teoria do cinema pela Universidade de São Francisco, Califórnia, Català vem se dedicando nas duas últimas décadas à pesquisa nas áreas da cultura visual e dos estudos da imagem.Nesta entrevista, Josep Maria Català fala sobre mudanças de mentalidade na relação dos artistas com o real como matériaprima para a fotografia e o documentário; os deslocamentos e processos de ressignificação promovidos pela arte contemporânea e pelo cinema nos processos de criação a partir do arquivo e a complexificação tanto dos dispositivos quanto da relação do espectador com as imagens. A entrevista foi realizada em julho de 2012 na Faculdade de Comunicação da UAB

The MIDAS telescope for microwave detection of ultra-high energy cosmic rays

We present the design, implementation and data taking performance of the MIcrowave Detection of Air Showers (MIDAS) experiment, a large field of view imaging telescope designed to detect microwave radiation from extensive air showers induced by ultra-high energy cosmic rays. This novel technique may bring a tenfold increase in detector duty cycle when compared to the standard fluorescence technique based on detection of ultraviolet photons. The MIDAS telescope consists of a 4.5 m diameter dish with a 53-pixel receiver camera, instrumented with feed horns operating in the commercial extended C-Band (3.4 -- 4.2 GHz). A self-trigger capability is implemented in the digital electronics. The main objectives of this first prototype of the MIDAS telescope - to validate the telescope design, and to demonstrate a large detector duty cycle - were successfully accomplished in a dedicated data taking run at the University of Chicago campus prior to installation at the Pierre Auger Observatory.Comment: 13 pages, 18 figure

Spin Accumulation Encoded in Electronic Noise for Mesoscopic Billiards with Finite Tunneling Rates

We study the effects of spin accumulation (inside reservoirs) on electronic transport with tunneling and reflections at the gates of a quantum dot. Within the stub model, the calculation focus on the current-current correlation function for the flux of electrons injected into the quantum dot. The linear response theory used allows to obtain the noise power in the regime of thermal crossover as a function of parameters that reveal the spin polarization at the reservoirs. The calculation is performed employing diagrammatic integration within the universal groups (ensembles of Dyson) for a non-ideal, non-equilibrium chaotic quantum dot. We show that changes in the spin distribution determines significant alteration in noise behavior at values of the tunneling rates close to zero, in the regime of strong reflection at the gates.Comment: New version, 8 pages, 5 figure

Antifungal Potential of Copper(II), Manganese(II) and Silver(I) 1,10-Phenanthroline Chelates Against Multidrug-Resistant Fungal Species Forming the Candida haemulonii Complex: Impact on the Planktonic and Biofilm Lifestyles

Candida haemulonii, Candida haemulonii var. vulnera and Candida duobushaemulonii, which form the C. haemulonii complex, are emerging etiologic agents of fungal infections known to be resistant to the most commonly used antifungals. The well-established anti-Candida potential ofmetal complexes containing 1,10-phenanthroline (phen) ligands encouraged us to evaluate different copper(II), manganese(II), and silver(I) phen chelates for their ability to inhibit planktonic growth and biofilm of C. haemulonii species complex. Two novel coordination complexes, {[Cu(3,6,9-tdda)(phen)2].3H2O.EtOH}n and [Ag2(3,6,9-tdda)(phen)4].EtOH (3,6,9-tddaH2 = 3,6,9-trioxaundecanedioic acid), were synthesized in a similar fashion to the other, previously documented, sixteen copper(II), manganese(II), and silver(I) chelates employed herein. Three isolates of each C. haemulonii species complex were used and the effect of the metal chelates on viability was determined utilizing the CLSI standard protocol and on biofilm-growing cells using the XTT assay. Cytotoxicity of the chelates was evaluated by the MTT assay, employing lung epithelial cells. The majority of the metal chelates were capable of interfering with the viability of planktonic-growing cells of all the fungal isolates

What are the advantages of living in a community? A microbial biofilm perspective!

Biofilm formation is the preferred mode of growth lifestyle for many microorganisms, including bacterial and fungal human pathogens. Biofilm is a strong and dynamic structure that confers a broad range of advantages to its members, such as adhesion/cohesion capabilities, mechanical properties, nutritional sources, metabolite exchange platform, cellular communication, protection and resistance to drugs (e.g., antimicrobials, antiseptics, and disinfectants), environmental stresses (e.g., dehydration and ultraviolet light), host immune attacks (e.g., antibodies, complement system, antimicrobial peptides, and phagocytes), and shear forces. Microbial biofilms cause problems in the hospital environment, generating high healthcare costs and prolonged patient stay, which can result in further secondary microbial infections and various health complications. Consequently, both public and private investments must be made to ensure better patient management, as well as to find novel therapeutic strategies to circumvent the resistance and resilience profiles arising from biofilm-associated microbial infections. In this work, we present a general overview of microbial biofilm formation and its relevance within the biomedical context

GOVERNANÇA DA POLÍTICA DE DESENVOLVIMENTO TERRITORIAL NO RIO GRANDE DO SUL: DINÂMICAS NO CONTEXTO SOCIOAMBIENTAL DOS TERRITÓRIOS RURAIS LITORAL E CAMPOS DE CIMA DA SERRA

Em 2017, vivenciou-se uma drástica mudança no cenário político brasileiro. Foi nesse período que o Programa de Desenvolvimento Sustentável de Territórios Rurais (PRONAT), implementado desde 2004, foi encerrado, findando um ciclo da política pública de desenvolvimento territorial brasileiro. Nesse contexto, objetivou-se analisar a governança da política territorial no Rio Grande do Sul, destacando sua dinâmica, analisada a partir do cenário socioambiental dos territórios Litoral e Campos de Cima da Serra. O estado é o segundo com o maior número de territórios, abrangendo cerca de 85% de sua área. Dentre as estruturas de governança, destacam-se o Comitê Articulador Estadual e a Rede Estadual de NEDETs. Do total de 18 territórios rurais, 11 foram reconhecidos em 2013. Essa condição fez com que o estado acumulasse uma experiência de gestão na política territorial bastante diversificada, com ênfase na organização cooperativa do sistema de abastecimento de mercados institucionais e na inclusão da sociobiodiversidade.Palavras-chave: Políticas públicas. Desenvolvimento territorial. Sociobiodiversidade. GOVERNANCE OF THE TERRITORIAL DEVELOPMENT POLICY IN RIO GRANDE DO SUL: DYNAMICS IN THE SOCIAL AND ENVIRONMENTAL CONTEXT OF RURAL COASTAL TERRITORIES AND CIMA DA SERRA FIELDSIn 2017, there was a drastic change in the Brazilian political scene, during which time the Program for the Sustainable Development of Rural Territories (PRONAT), implemented since 2004, ended with the end of a cycle of public policy for Brazilian territorial development. In this context, the objective was to analyze the territorial politics governance in Rio Grande do Sul, highlighting its dynamics analyzed from the socio-environmental context of the Litoral and Campos de Cima da Serra territories. The state is the second with the largest number of territories, covering about 85% of its area. Among the governance structures, the State Articulating Committee and the NEDETs State Network stand out. Of the eighteen rural territories, eleven were recognized in 2013. This condition led the state to accumulate a very diversified territorial management experience, with emphasis on the cooperative organization of the institutional market supply system and the inclusion of socio-biodiversity. Keywords: Public policies. Territorial development. Sociobiodiversity.

Integrable twists in AdS/CFT

A class of marginal deformations of four-dimensional N=4 super Yang-Mills theory has been found to correspond to a set of smooth, multiparameter deformations of the S^5 target subspace in the holographic dual on AdS_5 x S^5. We present here an analogous set of deformations that act on global toroidal isometries in the AdS_5 subspace. Remarkably, certain sectors of the string theory remain classically integrable in this larger class of so-called gamma-deformed AdS_5 x S^5 backgrounds. Relying on studies of deformed su(2)_gamma models, we formulate a local sl(2)_gamma Lax representation that admits a classical, thermodynamic Bethe equation (based on the Riemann-Hilbert interpretation of Bethe's ansatz) encoding the spectrum in the deformed AdS_5 geometry. This result is extended to a set of discretized, asymptotic Bethe equations for the twisted string theory. Near-pp-wave energy spectra within sl(2)_gamma and su(2)_gamma sectors provide a useful and stringent test of such equations, demonstrating the reliability of this technology in a wider class of string backgrounds. In addition, we study a twisted Hubbard model that yields certain predictions of the dual beta-deformed gauge theory.Comment: v2: references and clarifications added, 46 page

Noradrenergic Control of Gene Expression and Long-Term Neuronal Adaptation Evoked by Learned Vocalizations in Songbirds

Norepinephrine (NE) is thought to play important roles in the consolidation and retrieval of long-term memories, but its role in the processing and memorization of complex acoustic signals used for vocal communication has yet to be determined. We have used a combination of gene expression analysis, electrophysiological recordings and pharmacological manipulations in zebra finches to examine the role of noradrenergic transmission in the brain’s response to birdsong, a learned vocal behavior that shares important features with human speech. We show that noradrenergic transmission is required for both the expression of activity-dependent genes and the long-term maintenance of stimulus-specific electrophysiological adaptation that are induced in central auditory neurons by stimulation with birdsong. Specifically, we show that the caudomedial nidopallium (NCM), an area directly involved in the auditory processing and memorization of birdsong, receives strong noradrenergic innervation. Song-responsive neurons in this area express α-adrenergic receptors and are in close proximity to noradrenergic terminals. We further show that local α-adrenergic antagonism interferes with song-induced gene expression, without affecting spontaneous or evoked electrophysiological activity, thus dissociating the molecular and electrophysiological responses to song. Moreover, α-adrenergic antagonism disrupts the maintenance but not the acquisition of the adapted physiological state. We suggest that the noradrenergic system regulates long-term changes in song-responsive neurons by modulating the gene expression response that is associated with the electrophysiological activation triggered by song. We also suggest that this mechanism may be an important contributor to long-term auditory memories of learned vocalizations