880 research outputs found
Effects of Fluoride on Potassium and Sodium Permeability of the Erythrocyte Membrane
One of the most important features of cell membranes i their capacity to discrimi-nate between ions of different sign or different chemical nature. In the erythrocyte membrane, coulombic forces seem to govern the discrimination between anions and cations. There is reason to believe that, without impeding the movements of anions, positive fixed charges impose a severe restriction on the movements of diffusible ca-tions between cells and medium. But although a number of very conspicuous changes of cation permeability with pH and ionic strength can be related to variations of the fixed charge density of the membrane (Passow, 1965; LaCelle and Rothstein, 1966), observations have been made that passive cation permeability is not entirely gov-erned by coulombic forces. In particular, it has been observed that a number of agents such as fluoride, lead, triose reductone, IAA and adenosine (Passow, 1964), and others are capable of inducing a selective increase in passive K + movements without greatly affecting Na + permeability. It is far from being clear whether these agents act on a physiologically operating cation control mechanism or open up chan-nels which are normally without any control function. Nevertheless, the selectivit
Neighbouring Link Travel Time Inference Method Using Artificial Neural Network
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.This paper presents a method for modelling relationship between road segments using feed forward back-propagation neural networks. Unlike most previous papers that focus on travel time estimation of a road based on its traffic information, we proposed the Neighbouring Link Inference Method (NLIM) that can infer travel time of a road segment (link) from travel time its neighbouring segments. It is valuable for links which do not
have recent traffic information. The proposed method learns the relationship between travel time of a link and traffic parameters of its nearby links based on sparse historical travel time data. A travel time data outlier detection based on Gaussian mixture
model is also proposed in order to reduce the noise of data before they are applied to build NLIM. Results show that the proposed method is capable of estimating the travel time on all traffic link categories. 75% of models can produce travel time data with mean absolute percentage error less than 22%. The proposed method performs better on major than minor links. Performance of the proposed method always dominates performance of traditional methods such as statistic-based and linear least square estimate methods
Estimation of Travel Times for Minor Roads in Urban Areas Using Sparse Travel Time Data
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link
The Wow Factor? A Comparative Study of the Development of Student Music Teachers' Talents in Scotland and Australia
For some time there has been debate about differing perspectives on musical gift and musical intelligence. One view is that musical gift is innate: that it is present in certain individuals from birth and that the task of the teacher is to develop the potential which is there. A second view is that musical gift is a complex concept which includes responses from individuals to different environments and communities (Howe and Sloboda, 1997). This then raises the possibility that musical excellence can be taught. We have already explored this idea with practising musicians (Stollery and McPhee, 2002). Our research has now expanded to include music teachers in formation, and, in this paper, we look at the influences in their musical development which have either 'crystallised' or 'paralysed' the musical talent which they possess. Our research has a comparative dimension, being carried out in Scotland and in Australia. We conclude that there are several key influences in the musical development of the individual, including home and community support, school opportunities and teaching styles and that there may be education and culture-specific elements to these influences
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