Competing for consciousness: Prolonged mask exposure reduces object substitution masking.

In object substitution masking (OSM) a sparse, temporally trailing 4-dot mask impairs target identification, even though it has different contours from, and does not spatially overlap with the target. Here, we demonstrate a previously unknown characteristic of OSM: Observers show reduced masking at prolonged (e.g., 640 ms) relative to intermediate mask durations (e.g., 240 ms). We propose that with prolonged exposure, the mask's visual representation is consolidated, which allows processing of the lingering target icon to be reinitiated, thereby improving performance. Our findings suggest that when the visual system is confronted with 2 temporally contiguous stimuli, although one may initially gain access to consciousness above the other, the “losing” stimulus is not irreversibly lost to awareness. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Development of a cost effective probe for the long term monitoring of straw bale buildings

This paper reviews current methodologies for measuring the moisture content of straw bale walls in buildings. It discusses the development of an affordable and accurate moisture probe that has been designed to be easily assembled by the builder or owner of a straw bale building from items readily available in the United Kingdom (UK). The probe uses a timber block inserted into the wall, relying upon the measurable moisture variances of the timber and relating this to the surrounding straw. The probes are designed to be used in pairs of varying length, taking measurements at different depths to give an estimate of the moisture gradient through the wall. In order to properly calibrate this device, a full set of sorption and desorption isotherms were established for both Oat and Wheat straw and three different timber species. The results from an environmental chamber have been compared to readings from specimens of the new probe installed in a straw bale house in the south west of the UK. The results were found to be consistent, to within 2%, with the laboratory findings.     

Thermal Probe Technology for Buildings: Transition from Laboratory to Field Measurements

This paper reports the results of an investigation into the transfer of thermal probe measurement technology from laboratory use to actual buildings in order to undertake the in situ determination of thermal material properties. The imperative reasons for using in situ measurements are (1) the impact of moisture content on thermal properties; (2) the possible wide range of variation of properties across most materials used in construction; and (3) the lack of data for new and innovative materials. Thermal probe technology offers the prospect of taking building specific data, addressing these issues. Based on commercially available thermal probes a portable measurement kit and accompanying measurement procedure have been developed. Three case study buildings, each having different materials, have been studied to ascertain whether or not the technique can be transferred to relatively uncontrolled environments and remain capable of achieving a precision that is similar to an ASTM standard that can be related to thermal conductivity measurements of building materials. The results show that this is indeed the case, and that the use of thermal probe technology may yield thermal properties that vary significantly from the laboratory values currently used in building thermal engineering calculations.     

Investigation into the Variations of Moisture Content of Two Buildings Constructed with Light Earth Walls

This paper briefly describes the background to light earth buildings and details a series of moisture measurements undertaken upon the clay and straw (light earth) constructed walls of two U.K.-based buildings. The methodology of measurement that was based upon previous studies undertaken on walls made from straw bales is described. A novel “in-wall” wet heating system used in one of the two buildings allows the investigation of the effects of direct wall heating upon the distribution of moisture in the walls. The influence of exterior and interior temperature and humidity are described as are the variations in moisture migration introduced by the in-wall heating system. It was concluded that both buildings have exterior wall moisture content readings that indicate little risk of degradation due to interior wall moisture levels (although the Studio walls do exhibit higher and if suffered over long time periods, dangerous moisture readings for part of the measurement period).     

Irregular Helium Bubbles In Niobium Alloys

Helium bubbles have been produced in niobium-1% Zr by ion implantation and their growth has been studied by transmission electron microscopy of annealed specimens. Bubbles are normally faceted and develop from tetrakaidodecahedra at short times to cuboids bounded by {100} faces after long annealing periods. This behaviour, together with the observation of steps on the faces of many bubbles, is accounted for in terms of competition between the conditions necessary for thermodynamic equilibrium and the kinetics of bubble motion. The larger bubbles must contain an excess gas pressure.     

The fate of helium implanted into vanadium AT V-20% Ti

It is not always possible to account for all the helium implanted into vanadium by assuming that the observed gas bubbles contain their equilibrium pressure of helium. We show that most bubbles are overpressurized and could easily contain the majority of implanted atoms. It is not necessary to postulate the existence of sub-microscopic gas bubbles or helium traps.     

The collapse of helium platelets in molybdenum

Platelets of helium in molybdenum have been observed to collapse into several small helium bubbles rather than into a single bubble [10]. We show that the driving force for collapse into n bubbles increases as n decreases. However, kinetic factors associated with the nucleation of ledges on the flat faces of the platelets ensure that the frequency of nucleation of several small bubbles far exceeds that for a single bubble. The temperature at which this collapse is expected correlates well with the observed platelet behaviour.