2,805 research outputs found
Fano resonances in plasmonic core-shell particles and the Purcell effect
Despite a long history, light scattering by particles with size comparable
with the light wavelength still unveils surprising optical phenomena, and many
of them are related to the Fano effect. Originally described in the context of
atomic physics, the Fano resonance in light scattering arises from the
interference between a narrow subradiant mode and a spectrally broad radiation
line. Here, we present an overview of Fano resonances in coated spherical
scatterers within the framework of the Lorenz-Mie theory. We briefly introduce
the concept of conventional and unconventional Fano resonances in light
scattering. These resonances are associated with the interference between
electromagnetic modes excited in the particle with different or the same
multipole moment, respectively. In addition, we investigate the modification of
the spontaneous-emission rate of an optical emitter at the presence of a
plasmonic nanoshell. This modification of decay rate due to electromagnetic
environment is referred to as the Purcell effect. We analytically show that the
Purcell factor related to a dipole emitter oriented orthogonal or tangential to
the spherical surface can exhibit Fano or Lorentzian line shapes in the near
field, respectively.Comment: 28 pages, 10 figures; invited book chapter to appear in "Fano
Resonances in Optics and Microwaves: Physics and Application", Springer
Series in Optical Sciences (2018), edited by E. O. Kamenetskii, A. Sadreev,
and A. Miroshnichenk
Solitary practices or social connections? : a comparative study of fathering and health experiences among white and African-Caribbean working class men
This study addresses the following research question: what are the implications of African-
Caribbean and White working class men's experiences within social connections (within
families, friendships, communities and workplaces), for fathering and health experiences?
The purposes of this study were to undertake a primary piece of intensive qualitative
research, and also to analyse, critically, the study's findings, in order to identify implications
for theory, policy, practice and research.
This investigation was critical, interpretative and exploratory, informed by the principles of
phenomenology and ethnography. Six African-Caribbean and seven White working class
men were recruited, using purposive sampling, for two semi-structured individual
interviews. This enabled the exploration of the interactive effects and processes of structure
and agency, in relation to social class, gender, and ethnicity.
The study did not find major differences between the experiences of these two groups of
men, although the assets and constraints related to African-Caribbean men's experiences of
ethnicity and racism within social connections were evident. Study findings, for both groups
of men, indicated that social connectedness within families, communities and workplaces
was highly valued, but social connections, material and structural factors also influenced the
health of the men interviewed. Furthermore, findings indicated that men's experiences of
social connectedness have limitations. Specifically, men's limited insights into the links
between social connectedness and health, men's perceived limitations with their
communication skills, their solitary methods of dealing with perceived vulnerability, but
also the uncertainty associated with their identities as men were significant findings. Indeed,
men's experiences of both solitary discourses and practices and social connectedness,
regarding fathering and health, were associated with discourses about masculinities.
Implications for existing theory, for example Connell's (1995) work regarding masculinities,
and Putnam's (1995) work regarding `social capital', are identified. In addition,
implications for research, policy and practice are examined, with specific reference to the
opportunities for mental health promotion with working class men who are fathers
Avaliação econômica de pastagens: método da taxa interna de retorno com uso de microcomputador.
As baixas qualidade e disponibilidade das pastagens, especialmente na estação seca, têm sido apontadas como as principais causas do baixo desfrute do rebanho brasileiro. Na tentativa de encontrar soluções para este problema, pesquisadores, extensionistas e produtores têm intensificado esforços na busca de gramíneas exóticas, bem como estratégias alternativas para formação e conservação de pastagem cultivada, para oferecer melhor alimentação para os rebanhos a custos mais baixos. Entretanto, um aspecto que deve ser levado em conta na busca da pastagem mais adequada é a multiplicidade de condições em cada fazenda. Diferentes categorias animais e condições de clima, solo, vegetação nativa e infraestrutura regional, determinam as espécies forrageiras e os sistemas de formação e conservação de pastagem mais adequados economicamente. Dentre os métodos de formação e conservação de pastagens, há um grande número de alternativas. O método de abertura da mata, mecânico ou manual, o aproveitamento Inicial da área, com lavoura ou capim. a intensidade de uso e conservação da pastagem. a freqüência de rocadas e adubação constituem decisões determinantes de custos e benefício das pastagens.bitstream/item/131376/1/avaliacao-economica-de-pastagens.pd
The monte Molião cistern Lagos, Portugal
Conhecida desde o século XIX, a cisterna de Monte
Molião constitui o elemento arquitectónico mais destacado
do sítio e o único equipamento putativamente público ali documentado até ao momento. A sua escavação em 2011 e 2014
permitiu obter importantes dados sobre a sua tipologia e as
técnicas empregues na sua construção, bem como documentar a estratigrafia correspondente à sua colmatação. Foi assim
possível determinar que esta estrutura corresponde ao modelo
dito a bagnarola, de origem púnica, podendo datar-se do final
da Idade do Ferro ou de Época Romana Republicana, tendo
sido sujeita a reparações durante este último período. Por outro lado, o último período de utilização desta cisterna parece
ter-se verificado entre o Principado de Augusto e o reinado de
Tibério, seguindo-se um período de abandono e o seu eventual entulhamento, datado pelos materiais aqui estudados da
segunda metade do século I.Known since the 19th century, the cistern of Monte
Molião is the most notable architectural element in the site
and the only likely public infrastructure identified so far in
this settlement. Its excavation, undertaken in 2011 and 2014,
has brought to light important data about its typology and
construction techniques; a complete stratigraphic sequence
corresponding to its filling has also been documented. This
structure can be attributed to the so-called a bagnarola model
which originated in the Punic world and could have been constructed either in the Late Iron Age or in the Roman Republican period, having also been repaired in the latter period. Its
last period of use, on the other hand, seems to fall within the
reign of Augustus or Tiberius, being followed by a period of
abandonment and eventually by its intentional filling which,
based on the material studied here, can be dated to the second
half of the 1st centuryCâmara Municipal de Lago
Calibração de um lisímetro simplificado de pesagem.
O crescente uso da água e a redução de sua disponibilidade têm se tornado preocupação cada vez maior em todo o mundo. Em termos mundiais, a agricultura é responsável pela utilização de 70% da água doce consumida no planeta, por isso tem sido alvo de crítica pela sociedade demandando que sua utilização seja da forma mais racional possível. O presente trabalho tem como objetivo a construção e calibração de um lisímetro de pesagem em solo não vegetado de custo reduzido
Properties of a New Group of Cosmic Nuclei: Results from the Alpha Magnetic Spectrometer on Sodium, Aluminum, and Nitrogen
We report the properties of sodium (Na) and aluminum (Al) cosmic rays in the rigidity range 2.15 GV to 3.0 TV based on 0.46 million sodium and 0.51 million aluminum nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. We found that Na and Al, together with nitrogen (N), belong to a distinct cosmic ray group. In this group, we observe that, similar to the N flux, both the Na flux and Al flux are well described by the sums of a primary cosmic ray component (proportional to the silicon flux) and a secondary cosmic ray component (proportional to the fluorine flux). The fraction of the primary component increases with rigidity for the N, Na, and Al fluxes and becomes dominant at the highest rigidities. The Na /Si and Al /Si abundance ratios at the source, 0.036 ±0.003 for Na /Si and 0.103 ±0.004 for Al /Si , are determined independent of cosmic ray propagation
The gastronomy essence in cultural valorization : the case of Slow Food in the Azores
O Slow Food é um movimento internacional que valoriza os produtos alimentares tradicionais, artesanais e locais. Privilegia a culinária na sua origem, relacionando-a com os hábitos e cultura de um povo. Preserva a biodiversidade e a sustentabilidade do mundo rural, defendendo o prazer de uma experiência gastronómica.
É um movimento que surge como expressão alternativa do fast food, mas ainda sem registo nos Açores. Este projeto promove a sua implementação nesta Região, com o aproveitamento dos recursos naturais, culturais, gastronómicos e tradicionais que tanto a valorizam. Tem por base a incrementação do valor da identidade gastronómica e cultural do arquipélago, potenciando o seu sector turístico.
Foram efetuados inquéritos a Chefs, empresários, outros agentes e pessoas singulares ligadas à restauração e à gastronomia local, para complementar o estudo de implementação deste conceito nos Açores. Os resultados demonstram que a maioria dos inquiridos já tem algum conhecimento da filosofia Slow Food, abordam o tema com entusiasmo e reconhecem ser uma experiência diferenciadora que valorizará a oferta turística.
O Slow Foodvisa atingir um nicho de mercado sensibilizado pela procura de produtos turísticos naturais, representando simultaneamente uma fuga aos destinos massificados, na procura do sossego e tranquilidade que a natureza pode oferecer.ABSTRACT: Slow Food is an international movement that values the regional traditions, artisanal and local food. It privileges the cuisine at its source linking it to the habits and culture of a people. It preserves biodiversity and the sustainability of the rural world, defending the pleasure of a fine dining experience.
This movement emerges as an alternative expression of fast food in the world today though does not yet exists in the Azores. This project promotes the implementation in this region, with the use of natural, cultural, gastronomic and traditional resources that both value. It is based on incrementing the value of the gastronomic and cultural identity of the archipelago, enhancing its tourist sector.
Questionnaire surveys were made to Chefs, managers, agents and other individuals linked to the restoration and local cuisine to complement the study of implementation of this concept in the Azores. The results show that the majority of respondents already have some knowledge of the Slow Food philosophy; they approach the subject with enthusiasm and acknowledge to be a distinctive experience that will value the tourist offer.
Slow Food aims to reach a niche market moved by demand for natural tourism products, while representing an escape from the mass market destinations in search of peace and tranquillity that nature can offer.N/
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