473 research outputs found
LicitaCon Cidadão como Ferramenta de Transparência na Análise de Parcerias Público-Privadas em Educação
This article is an excerpt from a broader research that proposes to constitute a database on public-private partnerships in the cities of the state of Rio Grande do Sul (RS), through different methodological strategies for collecting information. Among the strategies, the use of the LicitaCon Cidadão (LC) tool is highlighted in this article as an important alternative to identify the formats of contracts between the government and private sectors, the resources involved, the contracted institutions and their areas of action. The transformations in the role of the State, in the context of neoliberal globalization, and the ongoing proposal to modernize the public machine are analyzed as indispensable elements for the analysis of the scenario that provided legal security and the political movement in favor of a particular form of privatization of education. It is understood that the deepening of studies of this nature allows for further research, helping to elucidate the implications of private insertion in public education and in the training of children and young people, as well as in the formulation of public policies for the sector.O presente artigo é um recorte da pesquisa mais ampla que se propõe a constituir um banco de dados sobre as parcerias público-privadas nos municípios do estado do Rio Grande do Sul (RS), por meio de diferentes estratégias metodológicas de coleta das informações. Dentre as estratégias destaca-se neste artigo a utilização da ferramenta LicitaCon Cidadão (LC) como uma alternativa importante para identificar os formatos de contratos entre o poder público e setores privados, os recursos envolvidos, as instituições contratadas e as suas áreas de atuação. Analisam-se as transformações no papel do Estado, no contexto da globalização neoliberal, e a proposta em curso de modernização da máquina pública como elementos indispensáveis para a análise do cenário que propiciou a segurança jurídica e o movimento político em favor de uma forma particular de privatização da educação. Entende-se que o aprofundamento de estudos desta natureza permite a realização de novas pesquisas, colaborando na elucidação das implicações da inserção privada na educação pública e na formação de crianças e jovens, bem como na formulação de políticas públicas para o setor
Highly Differentiated Human Fetal RPE Cultures Are Resistant to the Accumulation and Toxicity of Lipofuscin-Like Material
PURPOSE. The accumulation of undigestible autofluorescent material (UAM), termed lipofuscin
in vivo, is a hallmark of aged RPE. Lipofuscin derives, in part, from the incomplete degradation
of phagocytized photoreceptor outer segments (OS). Whether this accumulated waste is toxic
is unclear. We therefore investigated the effects of UAM in highly differentiated human fetal
RPE (hfRPE) cultures.
METHODS. Unmodified and photo-oxidized OS were fed daily to confluent cultures of ARPE-19
RPE or hfRPE. The emission spectrum, composition, and morphology of resulting UAM were
measured and compared to in vivo lipofuscin. Effects of UAM on multiple RPE phenotypes
were assessed.
RESULTS. Compared to ARPE-19, hfRPE were markedly less susceptible to UAM buildup.
Accumulated UAM in hfRPE initially resembled the morphology of lipofuscin from AMD eyes,
but compacted and shifted spectrum over time to resemble lipofuscin from healthy aged
human RPE. UAM accumulation mildly reduced transepithelial electrical resistance,
ketogenesis, certain RPE differentiation markers, and phagocytosis efficiency, while inducing
senescence and rare, focal pockets of epithelial-mesenchymal transition. However, it had no
effects on mitochondrial oxygen consumption rate, certain other RPE differentiation markers,
secretion of drusen components or polarity markers, nor cell death.
CONCLUSIONS. hfRPE demonstrates a remarkable resistance to UAM accumulation, suggesting
mechanisms for efficient OS processing that may be lost in other RPE culture models.
Furthermore, while UAM alters hfRPE phenotype, the effects are modest, consistent with
conflicting reports in the literature on the toxicity of lipofuscin. Our results suggest that
healthy RPE may adequately adapt to and tolerate lipofuscin accumulation
Collective Excitation of Spatio-Spectrally Distinct Quantum Dots Enabled by Chirped Pulses
For a scalable photonic device producing entangled photons, it is desirable
to have multiple quantum emitters in an ensemble that can be collectively
excited, despite their spectral variability. For quantum dots, Rabi rotation,
the most popular method for resonant excitation, cannot assure a universal,
highly efficient excited state preparation, because of its sensitivity to the
excitation parameters. In contrast, Adiabatic Rapid Passage (ARP), relying on
chirped optical pulses, is immune to quantum dot spectral inhomogeneity. Here,
we advocate the robustness of ARP for simultaneous excitation of the biexciton
states of multiple quantum dots. For positive chirps, we find that there is
also regime of phonon advantage that widens the tolerance range of spectral
detunings. Using the same laser pulse we demonstrate the simultaneous
excitation of energetically and spatially distinct quantum dots. Being able to
generate spatially multiplexed entangled photon pairs is a big step towards the
scalability of photonic devices
Interactions between Spider Silk and Cells – NIH/3T3 Fibroblasts Seeded on Miniature Weaving Frames
Native spider silk does not require any modification to its application as a biomaterial that can rival any artificial material in terms of cell growth promoting properties. We could show adhesion mechanics on intracellular level. Additionally, proliferation kinetics were higher than in enzymatically digested controls, indicating that spider silk does not require modification. Recent findings concerning reduction of cell proliferation after exposure could not be met. As biotechnological production of the hierarchical composition of native spider silk fibres is still a challenge, our study has a pioneer role in researching cellular mechanics on native spider silk fibres
Spinning Gland Transcriptomics from Two Main Clades of Spiders (Order: Araneae) - Insights on Their Molecular, Anatomical and Behavioral Evolution
Characterized by distinctive evolutionary adaptations, spiders provide a comprehensive system for evolutionary and developmental studies of anatomical organs, including silk and venom production. Here we performed cDNA sequencing using massively parallel sequencers (454 GS-FLX Titanium) to generate ∼80,000 reads from the spinning gland of Actinopus spp. (infraorder: Mygalomorphae) and Gasteracantha cancriformis (infraorder: Araneomorphae, Orbiculariae clade). Actinopus spp. retains primitive characteristics on web usage and presents a single undifferentiated spinning gland while the orbiculariae spiders have seven differentiated spinning glands and complex patterns of web usage. MIRA, Celera Assembler and CAP3 software were used to cluster NGS reads for each spider. CAP3 unigenes passed through a pipeline for automatic annotation, classification by biological function, and comparative transcriptomics. Genes related to spider silks were manually curated and analyzed. Although a single spidroin gene family was found in Actinopus spp., a vast repertoire of specialized spider silk proteins was encountered in orbiculariae. Astacin-like metalloproteases (meprin subfamily) were shown to be some of the most sampled unigenes and duplicated gene families in G. cancriformis since its evolutionary split from mygalomorphs. Our results confirm that the evolution of the molecular repertoire of silk proteins was accompanied by the (i) anatomical differentiation of spinning glands and (ii) behavioral complexification in the web usage. Finally, a phylogenetic tree was constructed to cluster most of the known spidroins in gene clades. This is the first large-scale, multi-organism transcriptome for spider spinning glands and a first step into a broad understanding of spider web systems biology and evolution
Measurement of the Dipion Mass Spectrum in X(3872) -> J/Psi Pi+ Pi- Decays
We measure the dipion mass spectrum in X(3872)--> J/Psi Pi+ Pi- decays using
360 pb-1 of pbar-p collisions at 1.96 TeV collected with the CDF II detector.
The spectrum is fit with predictions for odd C-parity (3S1, 1P1, and 3DJ)
charmonia decaying to J/Psi Pi+ Pi-, as well as even C-parity states in which
the pions are from Rho0 decay. The latter case also encompasses exotic
interpretations, such as a D0-D*0Bar molecule. Only the 3S1 and J/Psi Rho
hypotheses are compatible with our data. Since 3S1 is untenable on other
grounds, decay via J/Psi Rho is favored, which implies C=+1 for the X(3872).
Models for different J/Psi-Rho angular momenta L are considered. Flexibility in
the models, especially the introduction of Rho-Omega interference, enable good
descriptions of our data for both L=0 and 1.Comment: 7 pages, 4 figures -- Submitted to Phys. Rev. Let
Search for Higgs Boson Decaying to b-bbar and Produced in Association with W Bosons in p-pbar Collisions at sqrt{s}=1.96 TeV
We present a search for Higgs bosons decaying into b-bbar and produced in
association with W bosons in p-pbar collisions at sqrt{s}=1.96 TeV. This search
uses 320 pb-1 of the dataset accumulated by the upgraded Collider Detector at
Fermilab. Events are selected that have a high-transverse momentum electron or
muon, missing transverse energy, and two jets, one of which is consistent with
a hadronization of a b quark. Both the number of events and the dijet mass
distribution are consistent with standard model background expectations, and we
set 95% confidence level upper limits on the production cross section times
branching ratio for the Higgs boson or any new particle with similar decay
kinematics. These upper limits range from 10 pb for mH=110 GeV/c2 to 3 pb for
mH=150 GeV/c2.Comment: 7 pages, 3 figures; updated title to published versio
Search for Second-Generation Scalar Leptoquarks in Collisions at =1.96 TeV
Results on a search for pair production of second generation scalar
leptoquark in collisions at =1.96 TeV are reported. The
data analyzed were collected by the CDF detector during the 2002-2003 Tevatron
Run II and correspond to an integrated luminosity of 198 pb. Leptoquarks
(LQ) are sought through their decay into (charged) leptons and quarks, with
final state signatures represented by two muons and jets and one muon, large
transverse missing energy and jets. We observe no evidence for production
and derive 95% C.L. upper limits on the production cross sections as well
as lower limits on their mass as a function of , where is the
branching fraction for .Comment: 9 pages (3 author list) 5 figure
Observation of Bs-Bsbar Oscillations
We report the observation of Bs-Bsbar oscillations from a time-dependent
measurement of the Bs-Bsbar oscillation frequency Delta ms. Using a data sample
of 1 fb^-1 of p-pbar collisions at sqrt{s}=1.96 TeV collected with the CDF II
detector at the Fermilab Tevatron, we find signals of 5600 fully reconstructed
hadronic Bs decays, 3100 partially reconstructed hadronic Bs decays, and 61500
partially reconstructed semileptonic Bs decays. We measure the probability as a
function of proper decay time that the Bs decays with the same, or opposite,
flavor as the flavor at production, and we find a signal for Bs-Bsbar
oscillations. The probability that random fluctuations could produce a
comparable signal is 8 X 10^-8, which exceeds 5 sigma significance. We measure
Delta ms = 17.77 +- 0.10 (stat) +- 0.07 (syst) ps^-1
and extract
|Vtd/Vts| = 0.2060 +- 0.0007 (exp) + 0.0081 - 0.0060 (theor).Comment: 9 pages, 5 figures, submitted to Physical Review Letter
Search for anomalous semileptonic decay of heavy flavor hadrons produced in association with a W boson at CDF II
We present a search for anomalous semileptonic decays of heavy flavor hadrons
produced in association with a boson, in proton-antiproton collisions at
sqrt{s}=1.96 TeV. We use 162 pb-1 of data collected with the CDF II detector at
the Fermilab Tevatron Collider. We select events with one W boson and at least
one jet with an identified secondary vertex. In the jets with a secondary
vertex we look for a semileptonic decay to a muon. We compare the number of
jets with both a secondary vertex and a semileptonic decay, and the kinematic
properties of these jets, with the standard model expectation of W plus heavy
flavor production and decay. No discrepancy is seen between the observation and
the expectation, and we set limits on the production cross section of a B-like
hadron with an anomalously high semileptonic branching ratio.Comment: 8 pages, 2 figures, submitted to PRD-RC; replaced to adjust the page
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