Recent experimental results in sub- and near-barrier heavy ion fusion reactions

Recent advances obtained in the field of near and sub-barrier heavy-ion fusion reactions are reviewed. Emphasis is given to the results obtained in the last decade, and focus will be mainly on the experimental work performed concerning the influence of transfer channels on fusion cross sections and the hindrance phenomenon far below the barrier. Indeed, early data of sub-barrier fusion taught us that cross sections may strongly depend on the low-energy collective modes of the colliding nuclei, and, possibly, on couplings to transfer channels. The coupled-channels (CC) model has been quite successful in the interpretation of the experimental evidences. Fusion barrier distributions often yield the fingerprint of the relevant coupled channels. Recent results obtained by using radioactive beams are reported. At deep sub-barrier energies, the slope of the excitation function in a semi-logarithmic plot keeps increasing in many cases and standard CC calculations over-predict the cross sections. This was named a hindrance phenomenon, and its physical origin is still a matter of debate. Recent theoretical developments suggest that this effect, at least partially, may be a consequence of the Pauli exclusion principle. The hindrance may have far-reaching consequences in astrophysics where fusion of light systems determines stellar evolution during the carbon and oxygen burning stages, and yields important information for exotic reactions that take place in the inner crust of accreting neutron stars.Comment: 40 pages, 63 figures, review paper accepted for EPJ

Contextualização no ensino de estatística: uma proposta para os anos finais do ensino fundamental

Acompanha: Sequência de ensino contemplando a estatística nos anos finais do ensino fundamental segundo pressupostos da contextualizaçãoThe present study aimed to examine the contributions that a sequence of teaching based on assumptions of contextualization can bring to the teaching of statistics in the final years of basic school. The literature review concerning the teaching of statistics relies on Cazorla (2002), Lopes (2003, 2008, 2010a, 2010b), Silva (2007), Andrade (2008), Cazorla, Kataoka and Silva (2010), Jacobini et al. (2010), Campos, Wodewotzki and Jacobini (2011), among others. As for context, the literature review supported by Brazil (1998b, 1999), Tufano (2001), Pais (2002, 2010), Ramos (2004), (2005), Sadovsky (2007), Luccas (2011), among others. With the intention of achieving the proposed goal, was developed in the year 2011 a applied research, interpretive analysis and qualitative, descriptive in a batch of students of 7° year of basic school to a State public College of the city of Ponta Grossa, Paraná. The review of literature pertaining to the search features based on Gil (1991, 2006), Chizzotti (2003, 2008), Silva and Menezes (2005), Moreira and Caleffe (2008), Alves-Mazzotti (2011), Sarmento (2011), Teixeira (2011), among others. First was conducted an analysis of previous performance of the students on the basic content of statistics, based on a diagnostic instrument called pre-test. Then it was applied a sequence of teaching directed to basic statistical content, through the use of data collected in their own class, i.e. through contextualization. It emerged during the implementation of education, a greater interest and motivation of students to classes, as well as greater involvement of learners with the contents. The results of the analysis of the performance of the students after teaching sequence showed that this contributed to a significant gain on the acquisition of basic statistical content by students of the final years basic school. It is considered that the activities undertaken with learners, contributed to the development of the skills of reasoning, thinking, and statistical literacy of those forming the necessary basis for that in the future these students can reach the level of statistical literacy that contemporary society requires. As the final product of this work was to elaborate a courseware to support teacher education sequence containing a contextualized on basic statistical content aimed at the basic school, which is attached to this dissertation.O presente trabalho teve como objetivo analisar as contribuições que uma sequência de ensino pautada nos pressupostos da contextualização poderá trazer para o ensino e aprendizagem de Estatística nos anos finais do Ensino Fundamental. A revisão de literatura referente ao ensino de Estatística apoia-se em Cazorla (2002), Lopes (2003, 2008, 2010a, 2010b), Silva (2007), Andrade (2008), Cazorla, Kataoka e Silva (2010), Jacobini et al. (2010), Campos, Wodewotzki e Jacobini (2011), dentre outros. Quanto a contextualização, a revisão de literatura apoia-se em Brasil (1998b, 1999), Tufano (2001), Pais (2002, 2010), Ramos (2004), Mello (2005), Sadovsky (2007), Luccas (2011), além de outros. Com a intenção de alcançar o objetivo proposto, foi desenvolvida no ano de 2011 uma pesquisa aplicada, qualitativa com análise interpretativa e, descritiva em uma turma de alunos do 7° ano do Ensino Fundamental de um colégio público estadual do município de Ponta Grossa, Paraná. A revisão de literatura referente às características da pesquisa fundamenta-se em Gil (1991, 2006), Chizzotti (2003, 2008), Silva e Menezes (2005), Moreira e Caleffe (2008), Alves-Mazzotti (2011), Sarmento (2011), Teixeira (2011), dentre outros. Primeiramente foi realizada uma análise do desempenho prévio dos alunos em relação a conteúdos básicos de Estatística, tendo como base um instrumento diagnóstico chamado pré – teste. Depois foi aplicada uma sequência de ensino direcionada a conteúdos básicos de Estatística, por meio da utilização de dados coletados na própria turma, ou seja, por meio da contextualização. Verificou-se durante a aplicação da sequência de ensino, um maior interesse e motivação dos alunos para as aulas, além de um maior envolvimento dos educandos com os conteúdos estudados. Os resultados da análise do desempenho dos alunos após a aplicação da sequência de ensino mostraram que essa contribuiu para que houvesse um ganho significativo quanto à aquisição de conteúdos básicos de Estatística por parte de educandos dos anos finais do Ensino Fundamental. Considera-se que as atividades realizadas com os educandos, contribuíram para o desenvolvimento das competências de raciocínio, pensamento e, letramento estatísticos desses, formando a base necessária para que futuramente esses alunos possam atingir o nível de letramento estatístico que a sociedade contemporânea exige. Como produto final deste trabalho foi elaborado um material didático de apoio ao professor contendo uma sequência de ensino contextualizada sobre conteúdos básicos de Estatística voltada ao Ensino Fundamental, o qual se encontra anexado a esta dissertação

International nosocomial infection control consortium (INICC) report, data summary of 36 countries, for 2004-2009

The results of a surveillance study conducted by the International Nosocomial Infection Control Consortium (INICC) from January 2004 through December 2009 in 422 intensive care units (ICUs) of 36 countries in Latin America, Asia, Africa, and Europe are reported. During the 6-year study period, using Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN; formerly the National Nosocomial Infection Surveillance system [NNIS]) definitions for device-associated health care-associated infections, we gathered prospective data from 313,008 patients hospitalized in the consortium's ICUs for an aggregate of 2,194,897 ICU bed-days. Despite the fact that the use of devices in the developing countries' ICUs was remarkably similar to that reported in US ICUs in the CDC's NHSN, rates of device-associated nosocomial infection were significantly higher in the ICUs of the INICC hospitals; the pooled rate of central line-associated bloodstream infection in the INICC ICUs of 6.8 per 1,000 central line-days was more than 3-fold higher than the 2.0 per 1,000 central line-days reported in comparable US ICUs. The overall rate of ventilator-associated pneumonia also was far higher (15.8 vs 3.3 per 1,000 ventilator-days), as was the rate of catheter-associated urinary tract infection (6.3 vs. 3.3 per 1,000 catheter-days). Notably, the frequencies of resistance of Pseudomonas aeruginosa isolates to imipenem (47.2% vs 23.0%), Klebsiella pneumoniae isolates to ceftazidime (76.3% vs 27.1%), Escherichia coli isolates to ceftazidime (66.7% vs 8.1%), Staphylococcus aureus isolates to methicillin (84.4% vs 56.8%), were also higher in the consortium's ICUs, and the crude unadjusted excess mortalities of device-related infections ranged from 7.3% (for catheter-associated urinary tract infection) to 15.2% (for ventilator-associated pneumonia). Copyright © 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved

Search for gravitational-wave transients associated with magnetar bursts in advanced LIGO and advanced Virgo data from the third observing run

Gravitational waves are expected to be produced from neutron star oscillations associated with magnetar giant f lares and short bursts. We present the results of a search for short-duration (milliseconds to seconds) and longduration (∼100 s) transient gravitational waves from 13 magnetar short bursts observed during Advanced LIGO, Advanced Virgo, and KAGRA’s third observation run. These 13 bursts come from two magnetars, SGR1935 +2154 and SwiftJ1818.0−1607. We also include three other electromagnetic burst events detected by FermiGBM which were identified as likely coming from one or more magnetars, but they have no association with a known magnetar. No magnetar giant flares were detected during the analysis period. We find no evidence of gravitational waves associated with any of these 16 bursts. We place upper limits on the rms of the integrated incident gravitational-wave strain that reach 3.6 × 10−²³ Hz at 100 Hz for the short-duration search and 1.1 ×10−²² Hz at 450 Hz for the long-duration search. For a ringdown signal at 1590 Hz targeted by the short-duration search the limit is set to 2.3 × 10−²² Hz. Using the estimated distance to each magnetar, we derive upper limits upper limits on the emitted gravitational-wave energy of 1.5 × 1044 erg (1.0 × 1044 erg) for SGR 1935+2154 and 9.4 × 10^43 erg (1.3 × 1044 erg) for Swift J1818.0−1607, for the short-duration (long-duration) search. Assuming isotropic emission of electromagnetic radiation of the burst fluences, we constrain the ratio of gravitational-wave energy to electromagnetic energy for bursts from SGR 1935+2154 with the available fluence information. The lowest of these ratios is 4.5 × 103

Open data from the third observing run of LIGO, Virgo, KAGRA, and GEO

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages

A joint Fermi-GBM and Swift-BAT analysis of gravitational-wave candidates from the third gravitational-wave observing run

We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search and the Swift-BAT search, we calculate flux upper limits and present joint upper limits on the gamma-ray luminosity of each GW. Given these limits, we constrain theoretical models for the emission of gamma rays from binary black hole mergers

Constraints on the cosmic expansion history from GWTC–3

We use 47 gravitational wave sources from the Third LIGO–Virgo–Kamioka Gravitational Wave Detector Gravitational Wave Transient Catalog (GWTC–3) to estimate the Hubble parameter H(z), including its current value, the Hubble constant H0. Each gravitational wave (GW) signal provides the luminosity distance to the source, and we estimate the corresponding redshift using two methods: the redshifted masses and a galaxy catalog. Using the binary black hole (BBH) redshifted masses, we simultaneously infer the source mass distribution and H(z). The source mass distribution displays a peak around 34 M⊙, followed by a drop-off. Assuming this mass scale does not evolve with the redshift results in a H(z) measurement, yielding ${H}_{0}={68}_{-8}^{+12}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ (68% credible interval) when combined with the H0 measurement from GW170817 and its electromagnetic counterpart. This represents an improvement of 17% with respect to the H0 estimate from GWTC–1. The second method associates each GW event with its probable host galaxy in the catalog GLADE+, statistically marginalizing over the redshifts of each event's potential hosts. Assuming a fixed BBH population, we estimate a value of ${H}_{0}={68}_{-6}^{+8}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ with the galaxy catalog method, an improvement of 42% with respect to our GWTC–1 result and 20% with respect to recent H0 studies using GWTC–2 events. However, we show that this result is strongly impacted by assumptions about the BBH source mass distribution; the only event which is not strongly impacted by such assumptions (and is thus informative about H0) is the well-localized event GW190814

CP 24 DETERMINATION OF POL YCYCUC AROMATIC HYDROCARBONS IN COMMERCIAL GRADE EDmLE OILS BY IDGH PERFORMANCE LIQUID CROMATOGRAPHY

'Polycyclicaromatic hydrocarbons (PAHs) are well known for their .mutagenic and carcinogenic activities.Their presence in edible fats and oils has been reported in literature and several developed countrieshave recommended a maximum limit of PAHs in these edibles. In India, data on PAHs in .ediblefats and oils is lacking. The PAHs analysis in four varieties of edible oils has been carried out lIsingHPLCand their qualitative and quantitative results have been reported