19,267 research outputs found
Law, environmental policy and Kantian philosophy
Are Kantian philosophy and its principle of respect for persons inadequate to the protection of environmental values? This paper answers this question by elucidating how Kantian ethics can take environmental values seriously. In the period that starts with the Critique of Judgment in 1790 and ends with the Metaphysics of Morals in 1797, the subject would have been approached by Kant in a different manner; although the respect that we may owe to non-human nature is still grounded in our duties to mankind, the basis for such respect stems from nature’s aesthetic properties, and the duty to preserve nature lies in our duties to ourselves. Compared to the “market paradigm”, as it is called by Gillroy (the reference is to a conception of a public policy based on a criterion of economic efficiency or utility), Kantian philosophy can offer a better explanation of the relationship between environmental policy and the theory of justice. Kantian justice defines the “just state” as the one that protects the moral capacities of its “active” citizens, as presented in the first Part of the Metaphysics of Morals. In the Kantian paradigm, the environmental risk becomes a “public” concern. That means it is not subsumed under an individual decision, based on a calculus
On the characterization of finite differences “optimal” meshes
AbstractRegridding methods has become an important tool in the integration of PDE systems whose solutions exhibit sharp transitions in spatial derivatives. This paper improves the results presented in an earlier contribution of the author and F. Oliveira (1988). Theoretical justifications of finite differences regridding criteria for the transport and heat equations are presented. The nonuniform meshes in the physical space are generated by the use of coordinate transforms which map them into uniform meshes in the computational space. After the two mesh systems have been generated two approaches are used for solving the PDE: to construct the approximations on the uniform mesh in the computational space or to construct the finite-difference approximations on the nonuniform mesh in the physical space. In this paper we are concerned with the question of the relationship between the two approaches, namely the characterization of the mesh density (coordinate transform) which improves the spatial accuracy of the approximation in the physical (computational) space
Charge confinement and Klein tunneling from doping graphene
In the present work, we investigate how structural defects in graphene can
change its transport properties. In particular, we show that breaking of the
sublattice symmetry in a graphene monolayer overcomes the Klein effect, leading
to confined states of massless Dirac fermions. Experimentally, this corresponds
to chemical bonding of foreign atoms to carbon atoms, which attach themselves
to preferential positions on one of the two sublattices. In addition, we
consider the scattering off a tensor barrier, which describes the rotation of
the honeycomb cells of a given region around an axis perpendicular to the
graphene layer. We demonstrate that in this case the intervalley mixing between
the Dirac points emerges, and that Klein tunneling occurs.Comment: 11 pages, 5 figure
Propriedades espectroscópicas, térmicas e eletroquímicas de complexos de cobre com poli(2-vinilpiridina)
TCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Físicas e Matemáticas. Curso de Química.O trabalho consiste no estudo dos espectros vibracionais na região do infravermelho, das curvas de termogravimetria e calorimetria exploratória diferencial para os complexos formados entre poli(2-vinilpiridina) (P2VP) e os sais de cobre: cloreto de cobre(II) e sulfato de cobre(II). Os resultados indicam que a complexação com o cloreto de cobre(II) ocorre pela formação de ligação entre o íon Cu(II) e os átomos de nitrogênio dos anéis piridínicos, e que a presença e concentração dos íons Cu(II) afetam decisivamente as propriedades térmicas do polímero para este caso. Para os complexos formados entre o polímero poli(2-vinilpiridina) e sulfato de cobre(II), a complexação também se dá através de formação de ligação entre o íon Cu(II) e os átomos de nitrogênio dos anéis piridínicos. Uma interpretação mais detalhada dos espectros vibracionais na região do infravermelho na região que caracteriza o tipo de coordenação do sulfato fica prejudicada devido a sobreposição de bandas com o polímero puro. Através das análises térmicas de calorimetria exploratória diferencial e termogravimetria pôde-se observar mudanças nas propriedades térmicas do polímero e que essas mudanças são dependentes da concentração dos íons Cu(II). Ambos os complexos apresentam uma antecipação na temperatura de degradação e um valor de Tg maior quando comparados ao do polímero puro, sendo observada uma maior variação do valor de Tg para os complexos formados com sulfato de cobre. A voltametria cíclica realizada no sistema eletrodo de cobre e soluções 0,1 mol.L-1 de P2VP e KSCN mostrou que o polímero poli(2-vinilpiridina) apresenta uma boa potencialidade como inibidor de corrosão para o cobre e, que o filme responsável por tal comportamento deva ser um complexo envolvendo Cu(I), P2VP e ânions tiocianato
Healthcare workers perception regarding hand hygiene
Objective: To verify aspects related to the perception of healthcare workers regarding hand hygiene. Methods:
Cross-sectional study in a emergency care unit at a university hospital in Belo Horizonte. A structured
questionnaire was applied to nursing and medical staff. The statistic program SPSS was used, descriptive and
univariate analysis were made. Results: Healthcare workers attributed as high the impact of infections on
clinical evolution of patients and the effectiveness of hand hygiene in controlling those infections. The rate for
self-reported compliance to hand hygiene was 76.0% for the nursing staff and 72.5% for medical staff, but lower
than 60.0% for coworkers. Conclusions: Healthcare workers perceive hand hygiene as an effective measure to
control infection and recognize that compliance rates of hand hygiene among health teams in general are low
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