11,907 research outputs found
Research and learning environment: the role of the teacher
In this paper, starting from a didactical proposal about the introduction of the concept of natural number, already experienced in some primary school classes, we report about the subsequent reorganization of it in a new experience, quite different from the previous one. This transformation arises from the necessity of taking into account both: the pupils as they are, namely as members of a community with certain characteristics and not others; and the teacher herself, if she wants to actively take part in the learning project that she is going to realise
The Role of Community Values in Wind Energy Development: Exploring the Benefits and Applications of Community Wind for Reducing Local Opposition to Wind Energy Systems
Worldwide, wind energy generation is growing rapidly as a cleaner and less invasive alternative to traditional fossil-fuel energy sources. Yet, in the United States, the advancement of wind energy has been stunted by three factors: (1) the uncertainty of the federal Production Tax Credit; (2) the lack of transmission lines connecting wind projects to electricity grids; and (3) enduring local cultural and aesthetic objections to wind turbines. Frustrated with the imbalanced allocation of costs and benefits imposed by most wind energy projects, some individuals and municipalities have deployed zoning laws, nuisance claims, or environmentalist arguments to discourage wind energy development in their area. “Community wind” is a model of wind energy generation that improves residents’ perception of turbines by using local ownership, services and utility grids to concentrate the economic benefits of wind power in the communities that produce it.
This paper sets forth a proposal for applying the community wind model in a suburban context, through the mechanism of the homeowner’s association (HOA). HOAs are uniquely situated to implement community wind to lower their energy costs, provide affordable housing, enhance local schools, and shift Americans’ perception of wind farms in a more positive direction
“‘Hel-heime!’: The Daring Love Between Men in Dome Karukoski’s Tolkien”
This article briefly summarizes the homo-amorous connections between members of the T.C.B.S. in the Karukoski\u27s film, Tolkien
Voltage dependence of Hodgkin-Huxley rate functions for a multi-stage K channel voltage sensor within a membrane
The activation of a channel sensor in two sequential stages during a
voltage clamp may be described as the translocation of a Brownian particle in
an energy landscape with two large barriers between states. A solution of the
Smoluchowski equation for a square-well approximation to the potential function
of the S4 voltage sensor satisfies a master equation, and has two frequencies
that may be determined from the forward and backward rate functions. When the
higher frequency terms have small amplitude, the solution reduces to the
relaxation of a rate equation, where the derived two-state rate functions are
dependent on the relative magnitude of the forward rates ( and
) and the backward rates ( and ) for each stage. In
particular, the voltage dependence of the Hodgkin-Huxley rate functions for a
channel may be derived by assuming that the rate functions of the first
stage are large relative to those of the second stage -
and . For a {\em Shaker} IR channel, the first forward
and backward transitions are rate limiting ( and ), and for an activation process with either two or three stages, the
derived two-state rate functions also have a voltage dependence that is of a
similar form to that determined for the squid axon. The potential variation
generated by the interaction between a two-stage ion channel and a
noninactivating ion channel is determined by the master equation for
ion channel activation and the ionic current equation when the ion
channel activation time is small, and if and , the system may exhibit a small amplitude oscillation between spikes,
or mixed-mode oscillation.Comment: 31 pages, 14 figure
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