Benchmarking of Monte Carlo Flux simulations of electrons in CO2

Electron velocity distribution functions (EVDFs) in CO2 obtained by means of the Monte Carlo Flux (MCF) method are compared with results from two-term and multi-term Boltzmann solvers. The MCF method provides detailed calculations of the EVDF through a highly efficient variance reduction technique. Benchmark calculations of Legendre polynomial coefficients of the EVDF expansion are reported for a wide range of reduced electric fields (E/N), showing excellent agreement with multi-term solutions. Rate coefficients of inelastic processes calculated from two-term Boltzmann solvers differ significantly, up to 70%, from MCF and multi-term solutions, due to the anisotropy of the EVDF. An extension of the method to consider the thermal distribution of the background gas is also presented. This extension, together with an accurate description of the population of rotationally and vibrationally excited states, provides excellent agreement with measured transport coefficients at low E/N. A good agreement is obtained at moderate E/N between experimental values of dissociation rate coefficients and MCF calculations after careful consideration and analysis of several cross sections data sets.</p

Benchmarking of Monte Carlo flux simulations of electrons in CO2

Electron velocity distribution functions (EVDFs) in CO2 obtained by means of the Monte Carlo flux (MCF) method are compared with results from two-term and multi-term Boltzmann solvers. The MCF method provides detailed calculations of the EVDF through a highly efficient variance reduction technique. Benchmark calculations of Legendre polynomial coefficients of the EVDF expansion are reported for a wide range of reduced electric fields (E/N), showing excellent agreement with multi-term solutions. Rate coefficients of inelastic processes calculated from two-term Boltzmann solvers differ significantly, up to 70%, from MCF and multi-term solutions, due to the anisotropy of the EVDF. An extension of the method to consider the thermal distribution of the background gas is also presented. This extension, together with an accurate description of the population of rotationally and vibrationally excited states, provides excellent agreement with measured transport coefficients at low E/N. A good agreement is obtained at moderate E/N between experimental values of dissociation rate coefficients and MCF calculations after careful consideration and analysis of several cross sections data sets

On the Temperature Distribution Inside a Tree Under Fire Conditions

A simple and efficient numerical scheme is presented for the prediction of temperature field distribution inside a tree trunk subjected to ground fire conditions. The trunk is modeled by a cylinder of circular cross section and unit length, through which the time-dependent heat conduction equation is numerically integrated. The model is partly validated in laboratory and then applied to the case of a prescribed ground fire inside a Pinus pinmter stand

Managing the Reproductive Development of Grasses by Grazing Practices

Grazing natural grassland communities is necessary for both productive (feeding herbivores) and environmental (maintenance of open landscapes) objectives. Management guidelines should take into account the functional diversity of plant species between and within grassland communities. The management of the heading stage of grasses by grazing is an important tool to maintain acceptable forage quality and to avoid the seeding of low-valued species. The heading stage should be managed even in extensive systems and this needs a good knowledge of the phenological development of dominant species. In this work we illustrate the approach through the study of the development of four contrasting grasses and analysing the consequences for grazing management. This work concerned only diversity of the plant components of the grassland ecosystem

The UCSD HIRES/KeckI Damped Lya Abundance Database: II. The Implications

We present a comprehensive analysis of the damped Lya abundance database presented in the first paper of this series. This database provides a homogeneous set of abundance measurements for many elements including Si, Cr, Ni, Zn, Fe, Al, S, Co, O, and Ar from 38 damped Lya systems with z > 1.5. With little exception, these damped Llya systems exhibit very similar relative abundances. There is no significant correlation in X/Fe with [Fe/H] metallicity and the dispersion in X/Fe is small at all metallicity. We search the database for trends indicative of dust depletion and in a few cases find strong evidence. Specifically, we identify a correlation between [Si/Ti] and [Zn/Fe] which is unambiguous evidence for depletion. We present a discussion on the nucleosynthetic history of the damped Lya systems by focusing on abundance patterns which are minimally affected by dust depletion. We find [Si/Fe] -> +0.25 dex as [Zn/Fe] -> 0 and that the [Si/Fe] values exhibit a plateau of ~+0.3 dex at [Si/H] < -1.5 dex. Together these trends indicate significant alpha-enrichment in the damped Lya systems at low metallicity, an interpretation further supported by the observed O/Fe, S/Fe and Ar/Fe ratios. We also discuss Fe-peak nucleosynthesis and the odd-even effect. To assess the impact of dust obscuration, we present estimates of the dust-to-gas ratios for the damped Lya sightlines and crudely calculate dust extinction corrections. The distribution of extinction corrections suggests the effects of dust obscuration are minimal and that the population of 'missing' damped systems has physical characteristics similar to the observed sample. We update our investigation on the chemical evolution of the early universe in neutral gas. [significantly abridged]Comment: 29 pages, 26 figures. Uses emulateapj.sty. Accepted to ApJ: Oct 15, 200

Infrared FeII Emission in Narrow-Line Seyfert 1 Galaxies

We obtained 0.8-2.4 micron spectra at a resolution of 320 km/s of four narrow-line Seyfert 1 galaxies in order to study the near-infrared properties of these objects. We focus on the analysis of the FeII emission in that region and the kinematics of the low-ionization broad lines. We found that the 1 micron FeII lines (9997 A, 10501 A, 10863 A and 11126 A) are the strongest FeII lines in the observed interval. For the first time, primary cascade lines of FeII arising from the decay of upper levels pumped by Ly-alpha fluorescence are resolved and identified in active galactic nuclei. Excitation mechanisms leading to the emission of the 1 micron FeII features are discussed. A combination of Ly-alpha fluorescence and collisional excitation are found to be the main contributors. The flux ratio between near-IR FeII lines varies from object to object, in contrast to what is observed in the optical region. A good correlation between the 1 micron and optical FeII emission is found. This suggests that the upper z4Fo and z4Do levels from which the bulk of the optical lines descend are mainly populated by the transitions leading to the 1 micron lines. The width and profile shape of FeII 11127, CaII 8642 and OI 8446 are very similar but significantly narrower than Pa-beta, giving strong observational support to the hypothesis that the region where FeII, CaII and OI are produced are co-spatial, interrelated kinematically and most probably located in the outermost portion of the BLR.Comment: Accepted for publication in ApJ - 35 page

Informal Caregivers’ Health Literacy in Lisbon, Portugal: A Profile for Health Promotion Prioritization

Health literacy (HL) allows people to access, understand and evaluate health information. Informal caregivers' levels of HL may impact long-term care outcomes. 'Informal caregivers' profile in Lisbon county: a health community approach' is a nurse-led research project aiming to assess informal caregivers' health literacy and associated factors in Lisbon county, as well as to foster the development of a local-specific health literacy strategy. A survey to identify a health/social caregiver profile, including questions about HL (HLS-EU-PT), was submitted to a representative sample of carers. Descriptive and bivariate inferential analysis was developed. Informal caregivers' level of HL was mostly sufficient (n = 99, 38%). More than 60% of caregivers have limited HL regarding health promotion. 'Access', 'Appraisal' and 'Use' are the information processing stages with lower mean scores of HL. Carers with low HL levels appear to be older and to have less education, low knowledge of community resources and decreased wellbeing (p < 0.05). A strategy focused on health promotion-related HL through primary care resources can potentially improve caregivers' knowledge, competencies and motivation, as well as health system sustainability. Reported HLS-EU-PT scores deserve special attention. Future work should emphasize the role of HL-associated factors and health outcomes for caregivers and cared-for persons.info:eu-repo/semantics/publishedVersio

Does Reality Overcome the Expected? Survey on Informal Caregivers' Profile: A Nurse-Led Study in Times of COVID-19

The increasing overload of chronic conditions raises challenges for the health system. Informal caregivers have a major role in ensuring the quality of life of the cared-for person, despite the reported lack of working resources which can lead to unmet needs. This article reports on the first part of a nurse-led research project entitled “Informal caregiver’ profiles in Lisbon county: a health community approach.’ We aimed to support decision-making by developing an informal caregiver profile to promote tailored interventions. A survey addressing the dyad was developed and submitted to a convenient, network-based, stratified sample of carers aged 18 years or above. More than thirty community partners supported the identification of caregivers. Data were submitted to univariate descriptive analysis. A profile of the cared-for person and the informal caregiver was uncovered by identifying 639 caregivers, of whom the majority lived with the cared-for person. Only four percent planned the transition to a caregiver role, and no more than 10% had access to support programs. Approximately half of the respondents found that COVID-19 negatively impacted their performance in the caregiver role. Developing a local and tailored strategy with collaboration between healthcare professionals, academics, and community partners is key to ensuring that meaningful support is provided to caregivers.info:eu-repo/semantics/publishedVersio