EQUIVARIANT PATH FIELDS ON TOPOLOGICAL MANIFOLDS

A classical theorem of H. Hopf asserts that a closed connected smooth manifold admits a nowhere vanishing vector field if and only if its Euler characteristic is zero. R. Brown generalized Hopf`s result to topological manifolds, replacing vector fields with path fields. In this note, we give an equivariant analog of Brown`s theorem for locally smooth G-manifolds where G is a finite group.

UNIT VECTOR FIELDS ON ANTIPODALLY PUNCTURED SPHERES: BIG INDEX, BIG VOLUME

We establish in this paper a lower bound for the volume of a unit vector field (v) over right arrow defined ou S(n) \ {+/-x}, n = 2,3. This lower bound is related to the sum of the absolute values of the indices of (v) over right arrow at x and -x.

Some classes of semisimple group (and loop) algebras over finite fields

We determine the structure of the semisimple group algebra of certain groups over the rationals and over those finite fields where the Wedderburn decompositions have the least number of simple components We apply our work to obtain similar information about the loop algebras of mdecomposable RA loops and to produce negative answers to the isomorphism problem over various fields (C) 2010 Elsevier Inc All rights reserved

Generalized pseudo-likelihood estimates for markov random fields on lattice

In this paper we generalize Besag's pseudo-likelihood function for spatial statistical models on a region of a lattice. The correspondingly defined maximum generalized pseudo-likelihood estimates (MGPLEs) are natural extensions of Besag's maximum pseudo-likelihood estimate (MPLE). The MGPLEs connect the MPLE and the maximum likelihood estimate. We carry out experimental calculations of the MGPLEs for spatial processes on the lattice. These simulation results clearly show better performances of the MGPLEs than the MPLE, and the performances of differently defined MGPLEs are compared. These are also illustrated by the application to two real data sets.

Deconstructing diversity discourses in the fields of educationnal management and leadership

Discourses of diversity have supplanted those of equal opportunity or social justice in many Western democratic societies. While the notion of diversity is seemingly empowering through its recognition of cultural, religious, racial and gender difference within nation states, the emergence of this discourse during the 1990s has been in the context of neoliberal managerialist discourses that assume social action is fully explicable through theories of maximizing self interest. Thus notions of diversity, while originating in collective demands of social movements of feminism, anti racism and multiculturalism of the 1970s and 1980s, have in recent times privileged learning and leadership as an individual accomplishment and not a collective practice. Thus the dominant discourse of diversity is more in alignment with the deregulatory aspects of the increasingly managerial and market orientation of schooling, decentring earlier discourses of more transformatory notions premised upon reducing inequality and discrimination and developing ‘inclusivity’ in and through schooling. This paper provides a contextual and conceptual framework through which to explore the intersections and divergences of discourses of diversity in schools and their practical application.

The influence of magnetic fields exposure on neurite outgrowth in PC12 rat pheochromocytoma cells

The aim of present work was to investigate the influence of magnetic fields exposure on neurite outgrowth in PC12 cells. The neurite number per cell, length of neurites and directions of neurite growth with respect to the direction of the magnetic field were analyzed after exposure to 50 Hz electromagnetic field for 96 h. A promotion was observed under a weak field (0.23 mT), as the average number of neurites per cell increased to 2.38±0.06 compared to 1.91±0.07 neurites/cell of the control dishes, while inhibition and directional outgrowth was evident under a relatively stronger field (1.32 mT). Our work shows that biological systems can be very sensitive to the strength of electromagnetic field.

Controlling the relative orientation between the two magnetic fields of a synchronous motor

A simple and reliable method for controlling the relative orientation between the two magnetic fields of a permanent magnet synchronous motor is presented. Finding the initial (at motor powering-up time) value of this relative location is essential for the proper operation of the motor. The feedback control loop used finds this initial relative orientation quickly. Further, using the proposed method allows considerable cost saving, as a transducer that is usually used for this purpose can be eliminated. The cost saving is most obvious in the case of linear motors and angle motors with large diameters. The way the problem is posed is an essential part of this work and it is the reason behind the apparent simplicity of the solution. The method relied upon a single sensor, and it has been tested when a relative encoder was used

Developing effective learning programs : what extension can learn from the fields of adult education and learning communities

Learning is an investment in capacity building that has and will continue to reap rewards for primary producers and government in terms of increased sustainable production, profitability, exports, jobs and sustainable rural communities. Primary production operates in a context of continual change and requires up to date, complex and varied skills of primary producers and land managers.

A recent national research project funded by the Department of Agriculture, Forestry and Fisheries Australia confirmed that application of best practice from the theory of adult education in designing and developing learning programs in primary industry results in learning activities that provide information that is relevant to farmers’ needs, delivered in an entertaining way, and that draws on examples directly relevant to the participants. As a result, the training often exceeds the expectations of the participants.

The project produced a self-assessment checklist to identify ways of improving the development and delivery of training for extension practitioners and training providers. The key issues include continuous monitoring of client’s needs, and actively seeking opportunities to meet and work with industry organisations, other training providers and funding bodies.

There appear to be two drivers for the development of learning programs. One is problems or opportunities identified by people and organisations that could be termed ‘scanners’ and who tend not to be potential participants, the other is learning needs expressed by individuals or enterprises who want to participate in learning activities (participants). Scanners are typically industry organisations, government agencies and researchers, but may include providers and participants. Extension practitioners are well-placed to act as scanners.

It is very important that farmers and farmer organisations contribute to the development of new learning programs. Without industry input and support, extension practitioners and training providers cannot be expected to ensure they meet client needs. In other words, to develop effective learning programs, there must an industry learning community of producers, industry organisations, extension practitioners and training providers and other stakeholders such as supply chain enterprises, government and researchers.