10 research outputs found
Contribuição do hacker para o desenvolvimento tecnológico da informática
Get PDFDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação.Dada a enorme importância política, econômica e social da Internet, urge realizar-se um estudo sobre a evolução das formas de invasão dos chamados piratas eletrônicos. Para tal, buscou-se primeiramente classificá-los de acordo com a terminologia empregada no ambiente virtual, resgatando a origem do termo hacker, o qual tem sofrido mutações devido ao uso equivocado pela mídia. Na seqüência, as falhas que são exploradas pelos piratas eletrônicos são apresentadas, seus modus operandis e as tecnologias de defesa e de prevenção, as quais são divulgadas e passíveis de conhecimento, embora sejam ignoradas ou desconhecidas por muitos administradores e desenvolvedores de sistemas, já que a insegurança nos sistemas é decorrente de falhas amplamente conhecidas com soluções já determinadas. Por fim, buscou-se resgatar a contribuição que tais piratas exercem no desenvolvimento e no aprimoramento tecnológico, evidenciado em suas habilidades, agregadas à dedicação e ao trabalho cooperativo, exigindo assim qualidade nos produtos e serviços oferecidos. Uma maneira de minimizar a insegurança dos sistemas, é manter um conhecimento detalhado e atualizado das tecnologias existentes, característica inerente aos piratas eletrônicos. Assim, reconhecendo suas habilidades e incentivando-os a aprimorarem os sistemas de segurança, os esforços que hoje são despendidos nestes sistemas, poderão ser transferidos para outros desafios
POLÍTICAS SOCIAIS BRASILEIRAS: Previdência Social e Assistência Social no ultraneoliberalismo.
No full textAbordagens terapêuticas inovadoras na gestão da dor crônica: uma síntese de evidências
Get PDFInovações terapêuticas, como o uso de células-tronco mesenquimais e plasma rico em plaquetas, oferecem avanços promissores na gestão da dor crônica, proporcionando não apenas alívio imediato, mas também abordando as causas subjacentes para melhorar a qualidade de vida dos pacientes. Este estudo teve como objetivo desenvolver uma síntese de evidências sobre abordagens terapêuticas inovadoras na gestão da dor crônica. Nesse sentido, foi desenvolvida uma revisão sistemática da literatura, utilizando Scielo, Lilacs e Medline como bases de dados. A partir da análise qualitativa dos resultados, concluiu-se que abordagens terapêuticas inovadoras, como fisioterapia, terapias cognitivo-comportamentais e intervenções farmacológicas específicas, são eficazes na gestão da dor crônica. A ênfase na personalização do tratamento, considerando a diversidade da condição, destaca-se como crucial para otimizar resultados
Anxiolytic and antioxidant effects of Euterpe oleracea Mart. (açaí) seed extract in adult rat offspring submitted to periodic maternal separation
Get PDFMany studies suggest a protective role of phenolic compounds in mood disorders. We aimed to assess the effect of Euterpe oleracea (açaí) seed extract (ASE) on anxiety induced by periodic maternal separation (PMS) in adult male rats. Animals were divided into 6 groups: control, ASE, fluoxetine (FLU), PMS, PMS+ASE, and PMS+FLU. For PMS, pups were separated daily from the dam for 3 h between postnatal day (PN) 2 and PN21. ASE (200 mg·kg−1·day−1) and FLU (10 mg·kg−1·day−1) were administered by gavage for 34 days after stress induction, starting at PN76. At PN106 and PN108, the rats were submitted to open field (OF) and forced swim tests, respectively. At PN110, the rats were sacrificed by decapitation. ASE increased time spent in the center area in the OF test, glucocorticoid receptors in the hypothalamus, tropomyosin receptor kinase B (TRKB) levels in the hippocampus, and nitrite levels and antioxidant activity in the brain stem (PMS+ASE group compared with PMS group). ASE also reduced plasma corticotropin-releasing hormone levels, adrenal norepinephrine levels, and oxidative damage in the brain stem in adult male offspring submitted to PMS. In conclusion, ASE treatment has an anti-anxiety effect in rats submitted to PMS by reducing hypothalamic–pituitary–adrenal axis reactivity and increasing the nitric oxide (NO)–brain-derived neurotrophic factor (BDNF)–TRKB pathway and antioxidant defense in the central nervous system.
Novelty
•ASE has anti-anxiety and antioxidant effects in early-life stress.
•ASE reduces hypothalamic–pituitary–adrenal axis reactivity.
•The anxiolytic effect of ASE may involve activation of the NO–BDNF–TRKB pathway in the central nervous system.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Measurement of the top quark pair production charge asymmetry in proton-proton collisions at root s=7 TeV using the ATLAS detector
Get PDFContains fulltext :
127828.pdf (Publisher’s version ) (Open Access)
Contains fulltext :
127828.pdf (Author’s version preprint ) (Open Access
Measurement of the top quark pair production cross section in <i>pp</i> collisions at √s=7 TeV in dilepton final states with ATLAS
Get PDFA measurement of the production cross section of top quark pairs (t<span style="text-decoration: overline">t</span>) in proton–proton collisions at a center-of-mass energy of 7 TeV recorded with the ATLAS detector at the Large Hadron Collider is reported. Candidate events are selected in the dilepton topology with large missing transverse energy and at least two jets. Using a data sample corresponding to an integrated luminosity of 35 pb<sup>−1</sup>, a t<span style="text-decoration: overline">t</span> production cross section σ t<span style="text-decoration: overline">t</span> = 177 ± 20(stat.) ± 14 (syst.) ± 7(lum.) pb is measured for an assumed top quark mass of <i>mt</i>=172.5 GeV. A second measurement requiring at least one jet identified as coming from a <i>b</i> quark yields a comparable result, demonstrating that the dilepton final states are consistent with being accompanied by <i>b</i>-quark jets. These measurements are in good agreement with Standard Model predictions
Search for flavour-changing neutral-current interactions of a top quark and a gluon in collisions at TeV with the ATLAS detector
Get PDFA search is presented for the production of a single top quark via
left-handed flavour-changing neutral-current (FCNC) interactions of a top
quark, a gluon and an up or charm quark. Two production processes are
considered: and . The analysis is based on
proton-proton collision data taken at a centre-of-mass energy of 13TeV with
the ATLAS detector at the LHC. The data set corresponds to an integrated
luminosity of 139 fb. Events with exactly one electron or muon, exactly
one -tagged jet and missing transverse momentum are selected, resembling the
decay products of a singly produced top quark. Neural networks based on
kinematic variables differentiate between events from the two signal processes
and events from background processes. The measured data are consistent with the
background-only hypothesis, and limits are set on the production cross-sections
of the signal processes: pb and pb at the 95% confidence
level, with being the sum of
branching ratios of all three leptonic decay modes of the boson. Based on
the framework of an effective field theory, the cross-section limits are
translated into limits on the strengths of the and couplings
occurring in the theory: TeV and
TeV. These bounds correspond to
limits on the branching ratios of FCNC-induced top-quark decays:
and
.Comment: 51 pages in total, author list starting page 35, 7 figures, 4 tables,
published by Eur. Phys. J. C, All figures including auxiliary figures are
available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/TOPQ-2018-06
Search for pairs of highly collimated photon-jets in pp collisions at √s = 13 TeV with the ATLAS detector
Get PDFResults of a search for the pair production of photon-jets—collimated groupings of photons—in the ATLAS detector at the Large Hadron Collider are reported. Highly collimated photon-jets can arise from the decay of new, highly boosted particles that can decay to multiple photons collimated enough to be identified in the electromagnetic calorimeter as a single, photonlike energy cluster. Data from proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of
36.7
fb
−
1
, were collected in 2015 and 2016. Candidate photon-jet pair production events are selected from those containing two reconstructed photons using a set of identification criteria much less stringent than that typically used for the selection of photons, with additional criteria applied to provide improved sensitivity to photon-jets. Narrow excesses in the reconstructed diphoton mass spectra are searched for. The observed mass spectra are consistent with the Standard Model background expectation. The results are interpreted in the context of a model containing a new, high-mass scalar particle with narrow width,
X
, that decays into pairs of photon-jets via new, light particles,
a
. Upper limits are placed on the cross section times the product of branching ratios
σ
×
B
(
X
→
a
a
)
×
B
(
a
→
γ
γ
)
2
for
200
GeV
<
m
X
<
2
TeV
and for ranges of
m
a
from a lower mass of 100 MeV up to between 2 and 10 GeV, depending upon
m
X
. Upper limits are also placed on
σ
×
B
(
X
→
a
a
)
×
B
(
a
→
3
π
0
)
2
for the same range of
m
X
and for ranges of
m
a
from a lower mass of 500 MeV up to between 2 and 10 GeV
Search for Higgs boson decays into two new low-mass spin-0 particles in the 4 channel with the ATLAS detector using collisions at TeV
Get PDFThis paper describes a search for beyond the Standard Model decays of the Higgs boson into a pair of new spin-0 particles subsequently decaying into -quark pairs, , using proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider at center-of-mass energy TeV. This search focuses on the regime where the decay products are collimated and in the range GeV and is complementary to a previous search in the same final state targeting the regime where the decay products are well separated and in the range GeV. A novel strategy for the identification of the decays is deployed to enhance the efficiency for topologies with small separation angles. The search is performed with 36 fb of integrated luminosity collected in 2015 and 2016 and sets upper limits on the production cross-section of , where the Higgs boson is produced in association with a boson.This paper describes a search for beyond the Standard Model decays of the Higgs boson into a pair of new spin-0 particles subsequently decaying into -quark pairs, , using proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider at center-of-mass energy TeV. This search focuses on the regime where the decay products are collimated and in the range GeV and is complementary to a previous search in the same final state targeting the regime where the decay products are well separated and in the range GeV. A novel strategy for the identification of the decays is deployed to enhance the efficiency for topologies with small separation angles. The search is performed with 36 fb of integrated luminosity collected in 2015 and 2016 and sets upper limits on the production cross-section of , where the Higgs boson is produced in association with a boson.This paper describes a search for beyond the Standard Model decays of the Higgs boson into a pair of new spin-0 particles subsequently decaying into -quark pairs, , using proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider at center-of-mass energy TeV. This search focuses on the regime where the decay products are collimated and in the range GeV and is complementary to a previous search in the same final state targeting the regime where the decay products are well separated and in the range GeV. A novel strategy for the identification of the decays is deployed to enhance the efficiency for topologies with small separation angles. The search is performed with 36 fb of integrated luminosity collected in 2015 and 2016 and sets upper limits on the production cross-section of , where the Higgs boson is produced in association with a boson
