Lateral hyperstriatal lesions disrupt simultaneous but not successive conditional discrimination learning of pigeons (Columba livia).

Explored, in 2 experiments, the effects of lateral vs medial laminar lesions of the hyperstriatum in pigeons; medial lesions were largely confined to the hyperstriatum accessorium, and lateral lesions to the hyperstriatum dorsale and hyperstriatum ventrale. In Exp 1, lateral, but not medial, lesions disrupted acquisition of a simultaneous conditional discrimination; both medial and lateral lesions disrupted reversal of the discrimination. The reversal deficits of the medial and lateral groups were quantitatively similar, and both groups showed exaggerated positional responding. In Exp 2, neither medial nor lateral lesions disrupted acquisition of a successive conditional discrimination. Lateral hyperstriatal damage does not obtain a general disruption of conditional learning; it is speculated that the lateral hyperstriatum may play a critical role in configural learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Holistic nursing--definition and realization

Single-channel properties of a delayed rectifier voltage-gated K+ channel (I-type) were investigated in peripheral myelinated axons from Xenopus laevis. Channels activated between -60 and -40 mV with a potential of half-maximal activation, E50, at -47.5 mV. Averaged single-channel currents activated with a time delay at all membrane potentials tested. Time to half-maximal activation decreased from 80 to 1.6 msec between -60 and +40 mV. The channel inactivated monoexponentially with a time constant of 10.9 sec at -40 mV. The time constant of deactivation was 126 msec at -80 mV and 16.9 msec at -110 mV. In symmetrical 105 mM K+, the single-channel conductance (gamma) was 22 and 13 pS at negative and positive membrane potentials, respectively, at 13-15 degrees C. In Na+ -rich solution with 2.5 mM extracellular K+ gamma was 7 pS and the reversal potential was negative to -80 mV, indicating a high selectivity for K+ over Na+. gamma depended on extracellular K+ concentration (KD = 19.6 mM) and temperature (Q10 = 1.45). External tetraethylammonium (TEA) reduced the apparent single-channel amplitude at all potentials tested with a half-maximal inhibiting concentration (IC50) of 0.6 mM. Open probability of the channel, but not single-channel current amplitude was decreased by extracellular dendrotoxin (DTX, IC50 = 6.8 nM). mast cell degranulating peptide (MCDP, IC50 = 41.9 microM). In Ringer solution the membrane potential of macroscopic I-channel patches was about -65 mV and depolarized under TEA and DTX. It is concluded that besides their activation during action potentials, I-channels may also stabilize the resting membrane potential.     

News

Clean Technologies and Environmental Policy -     

Fourth International Conference on Durability of Building Materials and Components

RILEM Bulletin

Fourth International Conference on Durability of Building Materials and Components     

Verifying anonymity in voting systems using CSP

We present formal definitions of anonymity properties for voting protocols using the process algebra CSP. We analyse a number of anonymity definitions, and give formal definitions for strong and weak anonymity, highlighting the difference between these definitions. We show that the strong anonymity definition is too strong for practical purposes; the weak anonymity definition, however, turns out to be ideal for analysing voting systems. Two case studies are presented to demonstrate the usefulness of the formal definitions: a conventional voting system, and Prêt à Voter, a paper-based, voter-verifiable scheme. In each case, we give a CSP model of the system, and analyse it against our anonymity definitions by specification checks using the Failures-Divergences Refinement (FDR2) model checker. We give a detailed discussion on the results from the analysis, emphasizing the assumptions that we made in our model as well as the challenges in modelling electronic voting systems using CSP.     

CO2 Retention in High-Alkali Borate Glasses

A study of the high-alkali region of glass formation in the system Na₂O +B₂O₃ reveals that retention of CO₂ from carbonate starting materials can become a serious preparative problem at the high-alkali extreme. Results presented for glasses prepared using both Na₂O and Na₂CO₃ show that residual CO₂ can lead to major differences in physical properties which in this work are represented by the viscosity-related glass transition temperature .     

Designing for reportability: sustainable gamification,public engagement,and promoting environmental debate

There is a growing emphasis in many countries on matters such as participation in e-government, e-democracy, the provision of forums for online debate, and so on. A critical issue in all of these cases is one of encouraging engagement across a broad spectrum of potentially interested parties and stakeholders. In this paper, we use an ethnographic study of an online event, designed to encourage debate, to explore some critical issues in how the mechanisms productive of debate have shifted in company with the Web 2.0 phenomenon. By contrasting this with a prior study of how players managed their gameplay in a multiplayer pervasive game, we focus upon how different ways of constructing games and events can have serious implications for their ordinary everyday reportability in routine face-to-face interactions. We conclude that designing for reportability should be an active consideration when designing the resources for online debate and consider some ways in which that might be accomplished.     

Continuous solvent extraction of sunflower,seed, groundnuts,palmkernels, rapeseed,and copra

In principle, the oil milling process is straightforward. The wide variety of equipment in use reflects, however, a multiparametric process. The main limiting parameters are kind of seed, oil content, particle strength, particle structure, temperature, moisture, particle size, residence time, mechanical forces, etc. Additionally, the seed specific parameters vary not only between kinds of seed but also for the same seed, due to different conditions in climate, soil, and harvesting. Therefore, equipment design must be widely based on statistical averages of the limiting parameters. In other words, exact precalculation of the single technological steps is impossible. As a consequence, for more than 5,000 years, the oil milling process has been in the stage of being optimized. The acutal technical standard is very satisfying, but there is still a strong need for further research and development. Currently, as in the past, the oil milling process seems to be not so much a science as an art.