44,405 research outputs found
Recommended from our members
Evolving structure-function mappings in cognitive neuroscience using genetic programming
A challenging goal of psychology and neuroscience is to map cognitive functions onto neuroanatomical structures. This paper shows how computational methods based upon evolutionary algorithms can facilitate the search for satisfactory mappings by efficiently combining constraints from neuroanatomy and physiology (the structures) with constraints from behavioural experiments (the functions). This methodology involves creation of a database coding for known neuroanatomical and physiological constraints, for mental programs made of primitive cognitive functions, and for typical experiments with their behavioural results. The evolutionary algorithms evolve theories mapping structures to functions in order to optimize the fit with the actual data. These theories lead to new, empirically testable predictions. The role of the prefrontal cortex in humans is discussed as an example. This methodology can be applied to the study of structures or functions alone, and can also be used to study other complex systems.
(This article does not exactly replicate the final version published in the Journal of Swiss Psychology. It is not a copy of the original published article and is not suitable for citation.
UK Competition Policy and Shareholder Value: The Impact of Merger Inquiries
Some previous studies have suggested that competition re´gimes can destroy shareholder
value. This study examines data on 50 mergers in the UK between 1989 and 2002. The
study confirms the finding from earlier studies of greater gains to shareholders in target
than bidding companies, but does not find evidence supporting overall loss of
shareholder value to target company shareholders when a merger is prohibited. It
finds evidence that when the regulatory re´gime is stable and well understood the capital
market behaves efficiently in response to new information. However, for a subgroup of
the mergers involving companies with a new regulatory re´gime, where the industry and
the stock market had little or no experience with respect to mergers, the capital market
operated less efficiently
Recording single-channel activity of inositol trisphosphate receptors in intact cells with a microscope, not a patch clamp.
Optical single-channel recording is a novel tool for the study of individual Ca2+-permeable channels within intact cells under minimally perturbed physiological conditions. As applied to the functioning and spatial organization of IP3Rs, this approach complements our existing knowledge, which derives largely from reduced systems - such as reconstitution into lipid bilayers and patch clamping of IP3Rs on the membrane of excised nuclei - where the spatial arrangement and interactions among IP3Rs via CICR are disrupted. The ability to image the activity of single IP3R channels with millisecond resolution together with localization of their positions with a precision of a few tens of nanometers both raises several intriguing questions and holds promise of answers. In particular, what mechanism underlies the anchoring of puffs and blips to static locations; why do these Ca2+ release events appear to involve only a very small fraction of the IP3Rs within a cell; and how can we reconcile the relative immotility of functional IP3Rs with numerous studies reporting free diffusion of IP3R protein in the ER membrane
Retention of ductility in high-strength steels
To produce high strength alloy steel with retention of ductility, include tempering, cooling and subsequent tempering. Five parameters for optimum results are pretempering temperature, amount of strain, strain rate, temperature during strain, and retempering temperature
Structure and stimulus familiarity: A study of memory in chess-players with functional magnetic resonance imaging.
A grandmaster and an international chess master were compared with a group of novices
in a memory task with chess and non-chess stimuli, varying the structure and familiarity
of the stimuli, while functional magnetic resonance images were acquired. The pattern
of brain activity in the masters was different from that of the novices. Masters showed
no differences in brain activity when different degrees of structure and familiarity where
compared; however, novices did show differences in brain activity in such contrasts. The
most important differences were found in the contrast of stimulus familiarity with chess
positions. In this contrast, there was an extended brain activity in bilateral frontal areas
such as the anterior cingulate and the superior, middle, and inferior frontal gyri; furthermore,
posterior areas, such as posterior cingulate and cerebellum, showed great bilateral activation.
These results strengthen the hypothesis that when performing a domain-specific task,
experts activate different brain systems from that of novices. The use of the expertsversus-
novices paradigm in brain imaging contributes towards the search for brain systems
involved in cognitive processes
Multipurpose binocular scanning apparatus
Optical gimballing apparatus directs narrow fields of view throughout solid angle approaching 4 pi steradians. Image rotation produced by scanning can be eliminated or altered by gear trains directly linked to the scanning drive assembly. It provides the basis for a binocular scanning capability
Protection Against Hearing Loss in General Aviation Operations, Phase II
An inflight evaluation of four aural protectors is presented. The hearing protection devices studied were ear muffs, plastic ear plugs, rubber ear plugs, and wax ear plugs. It is concluded that ear plugs are satisfactory for providing adequate sound attenuation in general aviation aircraft. However, two problems were found in the use of ear plugs; comfort and interference with cabin communications
A primer on quantum fluids
This book introduces the theoretical description and properties of quantum
fluids. The focus is on gaseous atomic Bose-Einstein condensates and, to a
minor extent, superfluid helium, but the underlying concepts are relevant to
other forms of quantum fluids such as polariton and photonic condensates. The
book is pitched at the level of advanced undergraduates and early postgraduate
students, aiming to provide the reader with the knowledge and skills to develop
their own research project on quantum fluids. Indeed, the content for this book
grew from introductory notes provided to our own research students. It is
assumed that the reader has prior knowledge of undergraduate mathematics and/or
physics; otherwise, the concepts are introduced from scratch, often with
references for directed further reading.Comment: 132 pages. Published as SpringerBriefs in Physics book. Typos
corrected in this versio
Asian finance and the role of bankruptcy
The degree to which bankruptcy is permitted to play a role in the allocation of capital is a key distinction between the Asian state-directed financial regime and the Western market-directed version. The paper discusses the two approaches to finance and argues that a major problem with the bank finance model used in many Asian countries is its minimization of bankruptcy risks. A three-sector development model (agriculture, manufacturing, and financial sector) is developed and simulated to compare the outcomes of the two approaches separately and then to evaluate the transition costs of switching from a state- to a market-directed financial regime. The simulation results suggest that the market approach results in a higher long-run growth path because it eliminates inefficient firms through bankruptcy. The results also suggest that switching from a state- to a market-directed model can be very costly to the economy, though the transition costs can be lowered somewhat by a delayed and phased-in liberalization. At the same time, a delayed and phased-in approach may induce other difficulties not considered in the model. Several policy implications are drawn from the model and simulation results; for example, development of an infrastructure to provide for orderly bankruptcy and the development of money and capital markets should be given high priority in the liberalization process.Banks and banking - Asia ; Bankruptcy
- …