351 research outputs found
Symplectic evolution of Wigner functions in markovian open systems
The Wigner function is known to evolve classically under the exclusive action
of a quadratic hamiltonian. If the system does interact with the environment
through Lindblad operators that are linear functions of position and momentum,
we show that the general evolution is the convolution of the classically
evolving Wigner function with a phase space gaussian that broadens in time. We
analyze the three generic cases of elliptic, hyperbolic and parabolic
Hamiltonians. The Wigner function always becomes positive in a definite time,
which is shortest in the hyperbolic case. We also derive an exact formula for
the evolving linear entropy as the average of a narrowing gaussian taken over a
probability distribution that depends only on the initial state. This leads to
a long time asymptotic formula for the growth of linear entropy.Comment: this new version treats the dissipative cas
REFLEXÕES ACERCA DOS DIREITOS DOS INDÍGENAS E DAS POPULAÇÕES TRADICIONAIS DA AMAZÔNIA
A História e a Geografia da humanidade, nas quais se refletem a trajetória do tempo e da espacialidade/territorialidade, foram e são construídas de uma forma não linear com muitos embates e lutas, cujos resultados na maioria das vezes apontam para uma narrativa ou uma metanarrativa que refletem o ponto de vista dos vencedores. O Brasil, país de herança colonizadora e expansionista, apresenta como resultado as contradições políticas, sociais, econômicas e espaciais/territoriais cristalizadas e que permanecem nos dias atuais, ainda que muito recentemente tenha procurado dar visibilidade aos excluídos, tanto da cidade quanto aqueles que habitam o campo – zona rural. A Amazônia, integrante desse processo da modernidade, não fica alheia a tais acontecimentos, ainda que apresente internamente suas próprias contradições e conflitos, sendo que por ser uma das últimas fronteiras econômicas apresenta uma dinamicidade que diretamente propicia uma série de ressignificações nos modos de vida e nas identidades dos categorizados pelo conhecimento científico como povos tradicionais – e que neste trabalho nos referiremos a eles como povos amazônicos, sejam ribeirinhos, indígenas, extrativistas ou pequenos agricultores, em decorrência da maneira de vivenciar suas territorialidades/espacialidades. O fato é que cada um desses povos, é tratado aqui como sendo formado por humanos e não como conceitos científicos ou objetos que se encontram numa grande encruzilhada entre a permanência e a mudança, entre o novo e o antigo, entre o “arcaico” e a modernidade. O artigo em si busca discutir o protagonismo dos povos amazônicos enquanto pessoas que buscam e reivindicam seus direitos na realidade enfrentada no seu cotidiano; assim esboçamos um recorte temporal a partir dos anos 1980 com o processo de abertura democrática do país, anos em que surgiram inúmeros movimentos de reinvindicação de direitos desses povos, até mesmo como compreensão da dívida social histórica a eles devida.Palavras Chave: Povos Amazônicos; Invisibilidade e Identidade; Modos de vida; Territorialidades.REFLECTIONS ON THE RIGHTS OF INDIGENOUS AND TRADITIONAL POPULATIONS OF THE AMAZONAbstractThe History and Geography of mankind, that reflect the trajectory of time and spatiality/territoriality, were and are constructed in a non-linear form with many clashes, fights and whose results most often point to a narrative or a metanarrative that reflects the point of view of the winners. Brazil, as a country of colonizing and expansionist heritage, presents as a result political, social, economic and territorial/spatial crystallized contradictions which remain in the present day, though very recently it has sought to give visibility to the excluded people, both those who live in city and rural area. The Amazon, as part of this process of modernity, is not unrelated to such events, although presents internally their own contradictions and conflicts, with and because is one of the last economic borders presents a dynamic that directly promotes a series of re meanings in the ways of life and identities of the categorized by scientific knowledge as traditional people - in this work we will refer to them as] Amazonian people, whether they be riparian, indigenous, extractives communities or small farmers , due to how they use to living their territorialities/spatiality‟s. The fact is that each of these people here is considered as formed by humans and not as categories and/or scientific concepts and/or objects that are in a great crossroads between permanence and change, between old and new, between the "archaic" and the modernity. The article itself seeks to discuss the leading role of the Amazonia people, while people who seek and claim their rights vis-à-vis the reality that is placed in their daily life; so we outlined a timeframe from the ‟80 years through the process of democratic openness in the country, years during which emerged numerous claims of rights movements of these people, even as understanding of the historical social debt owe it to them.Key Words: Amazonian Peoples; Invisibility and Identity; Ways of life; Territorialities
A Supersymmetric Stueckelberg U(1) Extension of the MSSM
A Stueckelberg extension of the MSSM with only one abelian vector and one
chiral superfield as an alternative to an abelian extension with Higgs scalars
is presented. The bosonic sector contains a new gauge boson Z' which is a sharp
resonance, and a new CP-even scalar, which combines with the MSSM Higgs bosons
to produce three neutral CP-even massive states. The neutral fermionic sector
has two additional fermions which mix with the four MSSM neutralinos to produce
an extended 6x6 neutralino mass matrix. For the case when the LSP is composed
mostly of the Stueckelberg fermions, the LSP of the MSSM will be unstable,
which leads to exotic decays of sparticles with many leptons in final states.
Prospects for supersymmetry searches and for dark matter are discussed.Comment: 10 page
Solar Intranetwork Magnetic Elements: bipolar flux appearance
The current study aims to quantify characteristic features of bipolar flux
appearance of solar intranetwork (IN) magnetic elements. To attack such a
problem, we use the Narrow-band Filter Imager (NFI) magnetograms from the Solar
Optical Telescope (SOT) on board \emph{Hinode}; these data are from quiet and
an enhanced network areas. Cluster emergence of mixed polarities and IN
ephemeral regions (ERs) are the most conspicuous forms of bipolar flux
appearance within the network. Each of the clusters is characterized by a few
well-developed ERs that are partially or fully co-aligned in magnetic axis
orientation. On average, the sampled IN ERs have total maximum unsigned flux of
several 10^{17} Mx, separation of 3-4 arcsec, and a lifetime of 10-15 minutes.
The smallest IN ERs have a maximum unsigned flux of several 10^{16} Mx,
separations less than 1 arcsec, and lifetimes as short as 5 minutes. Most IN
ERs exhibit a rotation of their magnetic axis of more than 10 degrees during
flux emergence. Peculiar flux appearance, e.g., bipole shrinkage followed by
growth or the reverse, is not unusual. A few examples show repeated
shrinkage-growth or growth-shrinkage, like magnetic floats in the dynamic
photosphere. The observed bipolar behavior seems to carry rich information on
magneto-convection in the sub-photospheric layer.Comment: 26 pages, 14 figure
Interferences minimization using solid phase extraction in a multiparametric sequential injection system
info:eu-repo/semantics/publishedVersio
Antimicrobial Activity of the Extract of Stem Bark of Diplotropis Ferruginea Benth
This is the first report about the antibacterial activity of Diplotropis ferruginea Benth. In this study, the ethanol extract of D. ferruginea was tested for its antimicrobial activity against strains gram-positive and gram-negative. In order to determine the minimal inhibitory concentration, assays were carried out by micro dilution method. The extract was screened for antimicrobial activity, and it showed antibacterial activity against Escherichia coli and Pseudomonas aeruginosa
MYCN expression induces replication stress and sensitivity to PARP inhibition in neuroblastoma
This study investigates the influence expression of the MYCN oncogene has on the DNA damage response, replication fork progression and sensitivity to PARP inhibition in neuroblastoma. In a panel of neuroblastoma cell lines, MYCN amplification or MYCN expression resulted in increased cell death in response to a range of PARP inhibitors (niraparib, veliparib, talazoparib and olaparib) compared to the response seen in non-expressing/amplified cells. MYCN expression slowed replication fork speed and increased replication fork stalling, an effect that was amplified by PARP inhibition or PARP1 depletion. Increased DNA damage seen was specifically induced in S-phase cells. Importantly, PARP inhibition caused a significant increase in the survival of mice bearing MYCN expressing tumours in a transgenic murine model of MYCN expressing neuroblastoma. Olaparib also sensitized MYCN expressing cells to camptothecin- and temozolomide-induced cell death to a greater degree than non-expressing cells. In summary, MYCN expression leads to increased replication stress in neuroblastoma cells. This effect is exaggerated by inhibition of PARP, resulting in S-phase specific DNA damage and ultimately increased tumour cell death. PARP inhibition alone or in combination with classical chemotherapeutics is therefore a potential therapeutic strategy for neuroblastoma and may be more effective in MYCN expressing tumours
Influência do sexo de indivíduos da mesma colônia no controle químico das populações do morcego hematófago Desmodus rotundus (Phyllostomidae) no estado de São Paulo
Biometric viscera and blood parameters of meat quails supplemented with inorganic selenium and vitamin E
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