Psilocybin impairs high-level but not low-level motion perception

The hallucinogenic serotonin(IA&2A) agonist psilocybin is known for its ability to induce illusions of motion in otherwise stationary objects or textured surfaces. This study investigated the effect of psilocybin on local and global motion processing in nine human volunteers. Using a forced choice direction of motion discrimination task we show that psilocybin selectively impairs coherence sensitivity for random dot patterns, likely mediated by high-level global motion detectors, but not contrast sensitivity for drifting gratings, believed to be mediated by low-level detectors. These results are in line with those observed within schizophrenic populations and are discussed in respect to the proposition that psilocybin may provide a model to investigate clinical psychosis and the pharmacological underpinnings of visual perception in normal populations.

Numerical methods for strong solutions of stochastic differential equations: an overview

This paper gives a review of recent progress in the design of numerical methods for computing the trajectories (sample paths) of solutions to stochastic differential equations. We give a brief survey of the area focusing on a number of application areas where approximations to strong solutions are important, with a particular focus on computational biology applications, and give the necessary analytical tools for understanding some of the important concepts associated with stochastic processes. We present the stochastic Taylor series expansion as the fundamental mechanism for constructing effective numerical methods, give general results that relate local and global order of convergence and mention the Magnus expansion as a mechanism for designing methods that preserve the underlying structure of the problem. We also present various classes of explicit and implicit methods for strong solutions, based on the underlying structure of the problem. Finally, we discuss implementation issues relating to maintaining the Brownian path, efficient simulation of stochastic integrals and variable-step-size implementations based on various types of control.

'Worldmarks': Web guidelines for socially and culturally responsive assessment in university classrooms

In the early 21st century, we need to prepare university students to navigate local and global cultures effectively and sensitively. These future professionals must develop comprehensive intercultural communication skills and understanding. Yet university assessment in Australia is often based on a western template of knowledge, which automatically places International, Indigenous, as well as certain groups of local students at a study disadvantage. It also ensures that Australian students from dominant groups are not given the opportunity to develop these vital intercultural skills. This paper explores the issues embedded in themes 1 and 4 of this conference and provides details of an innovative website developed at Queensland University of Technology in Brisbane, Australia, which encourages academic staff to investigate the hidden assumptions that can underpin their assessment practices. The website also suggests strategies academics can use to ensure that their assessment becomes more socially and culturally responsive.

The impact of Foreign Direct Investment and trade openness on ICT expansion: A comparative analysis of Asia-Pacific and Middle Eastern countries

This study investigates the impact of foreign direct investment (FDI) inflow and trade openness on the expansion of information and communication technologies (ICTs) for the period of 1996 to 2005, in the Asia-Pacific and Middle East regions. The results of regression analyses conducted indicate that while dissimilarities exist among the countries included in this study in terms of their level of socio-economic and political development, factors such as trade openness, education and the growth of GDP had a positive impact on their ICT development. While FDI inflow had positive impact on the expansion of ICTs on Asia-Pacific countries its impact on Middle Eastern countries was not statistically significant. The study results also show that governmental intervention in economic activities has a negative impact on ICT expansion in both regions. In the Middle East, regional conflict imposes additional negative impact on FDI inflow and trade openness and consequently, ICT expansion. The regression results show that those countries that implemented liberalization of their ICT sector were able to not only reduce the digital divide with other developed countries, but also increase their operations in both local and global markets.

The effect of inversion on the encoding of normal and “thatcherized” faces

In the "Thatcher illusion" a face, in which the eyes and mouth are inverted relative to the rest of the face, looks grotesque when shown upright but not when inverted. In four experiments we investigated the contribution of local and global processing to this illusion in normal observers. We examined inversion effects (i.e., better performance for upright than for inverted faces) in a task requiring discrimination of whether faces were or were not "thatcherized". Observers made same/different judgements to isolated face parts (Experiments 1-2) and to whole faces (Experiments 3-4). Face pairs had the same or different identity, allowing for different processing strategies using feature-based or configural information, respectively. In Experiment 1, feature-based matching of same-person face parts yielded only a small inversion effect for normal face parts. However, when feature-based matching was prevented by using the face parts of different people on all trials (Experiment 2) an inversion effect occurred for normal but not for thatcherized parts. In Experiments 3 and 4, inversion effects occurred with normal but not with thatcherized whole faces, on both same- and different-person matching tasks. This suggests that a common configural strategy was used with whole (normal) faces. Face context facilitated attention to misoriented parts in same-person but not in different-person matching. The results indicate that (1) face inversion disrupts local configural processing, but not the processing of image features, and (2) thatcherization disrupts local configural processing in upright faces.

Synchronization processes in nonlinear systems and their relation to cortical oscillatory dynamics

This thesis was focused on theoretical models of synchronization to cortical dynamics as measured by magnetoencephalography (MEG). Dynamical systems theory was used in both identifying relevant variables for brain coordination and also in devising methods for their quantification. We presented a method for studying interactions of linear and chaotic neuronal sources using MEG beamforming techniques. We showed that such sources can be accurately reconstructed in terms of their location, temporal dynamics and possible interactions. Synchronization in low-dimensional nonlinear systems was studied to explore specific correlates of functional integration and segregation. In the case of interacting dissimilar systems, relevant coordination phenomena involved generalized and phase synchronization, which were often intermittent. Spatially-extended systems were then studied. For locally-coupled dissimilar systems, as in the case of cortical columns, clustering behaviour occurred. Synchronized clusters emerged at different frequencies and their boundaries were marked through oscillation death. The macroscopic mean field revealed sharp spectral peaks at the frequencies of the clusters and broader spectral drops at their boundaries. These results question existing models of Event Related Synchronization and Desynchronization. We re-examined the concept of the steady-state evoked response following an AM stimulus. We showed that very little variability in the AM following response could be accounted by system noise. We presented a methodology for detecting local and global nonlinear interactions from MEG data in order to account for residual variability. We found crosshemispheric nonlinear interactions of ongoing cortical rhythms concurrent with the stimulus and interactions of these rhythms with the following AM responses. Finally, we hypothesized that holistic spatial stimuli would be accompanied by the emergence of clusters in primary visual cortex resulting in frequency-specific MEG oscillations. Indeed, we found different frequency distributions in induced gamma oscillations for different spatial stimuli, which was suggestive of temporal coding of these spatial stimuli. Further, we addressed the bursting character of these oscillations, which was suggestive of intermittent nonlinear dynamics. However, we did not observe the characteristic-3/2 power-law scaling in the distribution of interburst intervals. Further, this distribution was only seldom significantly different to the one obtained in surrogate data, where nonlinear structure was destroyed. In conclusion, the work presented in this thesis suggests that advances in dynamical systems theory in conjunction with developments in magnetoencephalography may facilitate a mapping between levels of description int he brain. this may potentially represent a major advancement in neuroscience.

The acquisition of French past tenses by tutored anglophone advanced learners : is aspect enough?

Following Andersen's (1986, 1991) study of untutored anglophone learners of Spanish, aspectual features have been at the centre of hypotheses on the development of past verbal morphology in language acquisition. The Primacy of Aspect Hypothesis claims that the association of any verb category (Aktionsart) with any aspect (perfective or imperfective) constitutes the endpoint of acquisition. However, its predictions rely on the observation of a limited number of untutored learners at the early stages of their acquisition, and have yet to be confirmed in other settings. The aim of the present thesis is to evaluate the explanatory power of the PAH in respect of the acquisition of French past tenses, an aspect of the language which constitutes a serious stumbling block for foreign learners, even those at the highest levels of proficiency (Coppieters 1987). The present research applies the PAH to the production of 61 anglophone 'advanced learners' (as defined in Bartning 1997) in a tutored environment. In so doing, it tests concurrent explanations, including the influence of the input, the influence of chunking, and the hypothesis of cyclic development. Finally, it discusses the cotextual and contextual factors that still provoke what Anderson (1991) terms "non-native glitches" at the final stage, as predicted by the PAH. The first part of the thesis provides the theoretical background to the corpus analysis. It opens with a diachronic presentation of the French past tense system focusing on present areas of competition and developments that emphasize the complexity of the system to be acquired. The concepts of time, grammatical aspect and lexical aspect (Aktionsart) are introduced and discussed in the second chapter, and a distinctive formal representation of the French past tenses is offered in the third chapter. The second part of the thesis is devoted to a corpus analysis. The data gathering procedures and the choice of tasks (oral and written film narratives based on Modern Times, cloze tests and acceptability judgement tests) are described and justified in the research methodology chapter. The research design was shaped by previous studies and consequently allows comparison with these. The second chapter is devoted to the narratives analysis and the third to the grammatical tasks. This section closes with a summary of discoveries and a comparison with previous results. The conclusion addresses the initial research questions in the light of both theory and practice. It shows that the PAH fails to account for the complex phenomenon of past tense development in the acquisitional settings under study, as it adopts a local (the verb phrase) and linear (steady progression towards native usage) approach. It is thus suggested that past tense acquisition rather follows a pendular development as learners reformulate their learning hypotheses and become increasingly able to shift from local to global cues and so to integrate the influence of cotext and context in their tense choice.

I like the floors

The use of wood in architectural design and the sustainable built environment

Episodes in the Malaysian auditing sage

Purpose – The purpose of this paper is to examine the various episodes in the Malaysian auditing saga, covering the period of the first 40 years post-independence in 1957 to just before the onset of the Asian Financial Crisis in 1997. Design/methodology/approach – Based on documentary analysis, the paper offers a historical account of the development of the auditing profession with reference to the dynamic changes in its political and socio-economic environment. Findings – The paper concludes that the function of auditing in Malaysian society responded to political-economic pressures over time viz. changing from maintaining the economic policy to serve Western investors to accommodating ethnic relations, and to strengthening the bond between local and global corporate elites and the political leaders. Originality/value – Since, little is known of the professionalisation process in Malaysia, our analysis of the structural conditions during the 40 years from the achievement of independence from the British in 1957 to just before the onset of the Asian Financial Crisis in 1997 and our assessment of their implications for auditing contributes to knowledge in this area

Integrating skills profiling and purchasing portfolio management:an opportunity for building purchasing capability

Kralijc’s (1983) purchasing portfolio approach holds that different types of purchases need different sourcing strategies, underpinned by distinct sets of resources and practices. The approach is widely deployed in business and extensively researched, and yet little research has been conducted on how knowledge and skills vary across a portfolio of purchases. This study extends the body of knowledge on purchasing portfolio management, and its application in the strategic development of purchasing in an organization, and on human resource management in the purchasing function. A novel approach to profiling purchasing skills is proposed, which is well suited to dynamic environments which require flexibility. In a survey, experienced purchasing personnel described a specific purchase and profiled the skills required for effective performance in purchasing that item. Purchases were categorized according to their importance to the organization (internally-oriented evaluation of cost and production factors) and to the supply market (externally-oriented evaluation of commercial risk and uncertainty). Through cluster analysis three key types of purchase situations were identified. The skills required for effective purchasing vary significantly across the three clusters (for 22 skills, p<0.01). Prior research shows that global organizations use the purchasing portfolio approach to develop sourcing strategies, but also aggregate analyses to inform the design of purchasing arrangements (local vs global) and to develop their improvement plans. Such organizations would also benefit from profiling skills by purchase type. We demonstrate how the survey can be adapted to provide a management tool for global firms seeking to improve procurement capability, flexibility and performance.

Travelling waves in a complex Ginzburg-Landau equation with time-delay feedback

One of the simplest ways to create nonlinear oscillations is the Hopf bifurcation. The spatiotemporal dynamics observed in an extended medium with diffusion (e.g., a chemical reaction) undergoing this bifurcation is governed by the complex Ginzburg-Landau equation, one of the best-studied generic models for pattern formation, where besides uniform oscillations, spiral waves, coherent structures and turbulence are found. The presence of time delay terms in this equation changes the pattern formation scenario, and different kind of travelling waves have been reported. In particular, we study the complex Ginzburg-Landau equation that contains local and global time-delay feedback terms. We focus our attention on plane wave solutions in this model. The first novel result is the derivation of the plane wave solution in the presence of time-delay feedback with global and local contributions. The second and more important result of this study consists of a linear stability analysis of plane waves in that model. Evaluation of the eigenvalue equation does not show stabilisation of plane waves for the parameters studied. We discuss these results and compare to results of other models.

Stabilization of standing waves through time-delay feedback

Standing waves are studied as solutions of a complex Ginzburg-Landau equation subjected to local and global time-delay feedback terms. The onset is described as an instability of the uniform oscillations with respect to spatially periodic perturbations. The solution of the standing wave pattern is given analytically and studied through simulations. © 2013 American Physical Society.

Automatic Discovery of Word Semantic Relations

In this paper, we propose an unsupervised methodology to automatically discover pairs of semantically related words by highlighting their local environment and evaluating their semantic similarity in local and global semantic spaces. This proposal di®ers from previous research as it tries to take the best of two different methodologies i.e. semantic space models and information extraction models. It can be applied to extract close semantic relations, it limits the search space and it is unsupervised.

Tutorial on Computing: Technological Advances, Social Implications, Ethical and Legal Issues

Computing and information technology have made significant advances. The use of computing and technology is a major aspect of our lives, and this use will only continue to increase in our lifetime. Electronic digital computers and high performance communication networks are central to contemporary information technology. The computing applications in a wide range of areas including business, communications, medical research, transportation, entertainments, and education are transforming local and global societies around the globe. The rapid changes in the fields of computing and information technology also make the study of ethics exciting and challenging, as nearly every day, the media report on a new invention, controversy, or court ruling. This tutorial will explore a broad overview on the scientific foundations, technological advances, social implications, and ethical and legal issues related to computing. It will provide the milestones in computing and in networking, social context of computing, professional and ethical responsibilities, philosophical frameworks, and social, ethical, historical, and political implications of computer and information technology. It will outline the impact of the tremendous growth of computer and information technology on people, ethics and law. Political and legal implications will become clear when we analyze how technology has outpaced the legal and political arenas.

Comments on multiple oscillatory solutions in systems with time-delay feedback

A complex Ginzburg-Landau equation subjected to local and global time-delay feedback terms is considered. In particular, multiple oscillatory solutions and their properties are studied. We present novel results regarding the disappearance of limit cycle solutions, derive analytical criteria for frequency degeneration, amplitude degeneration, frequency extrema. Furthermore, we discuss the influence of the phase shift parameter and show analytically that the stabilization of the steady state and the decay of all oscillations (amplitude death) cannot happen for global feedback only. Finally, we explain the onset of traveling wave patterns close to the regime of amplitude death.