Using a virtual environment to assess cognition in the elderly

Early diagnosis of Alzheimer’s disease (AD) is essential if treatments are to be administered at an earlier point in time before neurons degenerate to a stage beyond repair. In order for early detection to occur tools used to detect the disorder must be sensitive to the earliest of cognitive impairments. Virtual reality technology offers opportunities to provide products which attempt to mimic daily life situations, as much as is possible, within the computational environment. This may be useful for the detection of cognitive difficulties. We develop a virtual simulation designed to assess visuospatial memory in order to investigate cognitive function in a group of healthy elderly participants and those with a mild cognitive impairment (MCI). Participants were required to guide themselves along a virtual path to reach a virtual destination which they were required to remember. The preliminary results indicate that this virtual simulation has the potential to be used for detection of early AD since significant correlations of scores on the virtual environment with existing neuropsychological tests were found. Furthermore, the test discriminated between healthy elderly participants and those with a MCI.     

Copyright and creativity

In his new book, Free Culture (Penguin Press, 2004), Larry Lessig of Stanford Law School presents an excellent explanation of copyright law's effect on creativity - and of large corporations' effect on copyright law. Free Culture covers the history of copyright and its expansion from books to music, pictures, and videos, as well as its extension from 28 to 95 years. The book is remarkable because, unlike the vast majority of flaming on both sides of the downloading controversy, it presents both a factual argument and proposed solutions.     

Bigger share of a smaller pie [digital rights]

Do you like your music in Apple format (AIFF), Microsoft format (WMA), Real Networks style (RA), or in a public standard (MP3 or Ogg Vorbis)? Anyone listening to Internet radio stations or other online sounds is familiar with the frequent need to choose between format and player (typically, for streaming, between Real Networks and Windows Media). This is not a technological issue: the various sound formats all provide acceptable quality. Under typical listening conditions Such as walking along a street with traffic next to You or in in office with small and inadequate speakers; any difficulty you have hearing the music won't be from the encoding method's limitations. Instead, we have a set of companies who think the best way to dominate the online music business is to tie the format and player together to lock in customers. We're in the middle of a contest to see whether one company can dominate the legal downloading business by controlling the format in which music is sold. The article looks at whether Apple, Microsoft, or someone else can establish a monopoly, so that people will buy only their software and audio format.     

Silicon ribbon growth via the ribbon-to-ribbon (RTR) technique: Process update and material characterization

The current state of development of the RTR process for silicon ribbon growth is reviewed. Present growth capabilities, material characterization, and device performance are summarized. Specific process problems, such as poor laser coupling efficiencies, are discussed and approaches to their solution are described. Problems related to thermal stresses are discussed in some detail. Stress induced birefringence measurements are used to evaluate residual stresses. A linear temperature profile postheater is effective for reduction of residual stresses. A correlation may be obtained between minority carrier diffusion lengths, dislocation densities, and thermal stress levels.     

The Computational Analysis of Protein Structures: Sources,Methods, Systems and Results

Computational molecular biology is a relatively new specialty that has arisen in response to the very large amount and quality of data currently being produced, including gene and protein sequences (“one-dimensional” information) and nucleic acid and protein structures (“three-dimensional” information). Many important biological investigations can be carried out only through effective computational access to the entire corpus of data. This has stimulated the development of data banks and information retrieval systems. For example, after determination of a new gene sequence, one would like to know whether it is possible to say anything about its structure and function. To try to answer this question one screens the sequence of the corresponding protein for a significant similarity to a protein of known structure. In this article we shall describe the kinds of inferences that are possible if such a relationship is found.     

Spectral-domain phase microscopy with improved sensitivity using two-dimensional detector arrays

In this work we demonstrate the use of two-dimensional detectors to improve the signal-to-noise ratio (SNR) and sensitivity in spectral-domain phase microscopy for subnanometer accuracy measurements. We show that an increase in SNR can be obtained, from 82 dB to 105 dB, using 150 pixel lines of a low-cost CCD camera as compared to a single line, to compute an averaged axial scan. In optimal mechanical conditions, phase stability as small as 92 μrad, corresponding to 6 pm displacement accuracy, could be obtained. We also experimentally demonstrate the benefit of spatial-averaging in terms of the reduction of signal fading due to an axially moving sample. The applications of the improved system are illustrated by imaging live cells in culture.     

Incentives to Innovate: Improve the Past or Break with It?

Does more expansive copyright law increase creativity by discouraging adaptations of existing work? The author discusses examples from cooking, boatbuilding, and the theater.     

Caffeine, Priming, and Tip of the Tongue: Evidence for Plasticity in the Phonological System.

A study was performed involving phonological priming and tip-of-the-tongue states (TOTs) in which participants took either 200 mg of caffeine or placebo. Results show a clear positive priming effect produced for the caffeine group when primed with phonologically related words. When primed with unrelated words, the caffeine subgroup produced a significant increase in the number of TOTs. This contrasting effect provides evidence that the positive priming of caffeine was not a result of caffeine's well-known alertness effects. For placebo, a significant negative effect occurred with the related-word priming condition. The results support the novel hypothesis that the blocking of A, adenosine receptors by caffeine induces an increased short-term plasticity effect within the phonological retrieval system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)