Innovation of a Reinforcer Preference Assessment with the Difficult to Test

In this study, we continued evaluation of a two-choice preference assessment aimed at identifying a hierarchy of reinforcers for individuals with only one voluntary motor sequence—closing and releasing an adaptive switch. We assessed preferences among types of sensory stimulation in 6 adults with multiple profound impairments using concurrent synchronous reinforcement contingencies. Pre-experimental assessments with various types of stimulation led to the selection of music (A), vibration (B), and either olfactory or visual stimulation (C) as the 3 modalities for continued testing. Each participant received opportunities for familiarization with each type of stimulation in blocks of six 20-min sessions in which the closure of an adaptive switch produced the stimulation for as long as the switch remained closed. Next, participants could choose between pairs of types of stimulation in blocks of 12 sessions. In the first 6 of the 12 sessions, switch closure activated one type (e.g., A) and switch release activated the contrasted type (e.g., B). In the second 6 sessions, the contingencies were reversed. Two additional 12-session blocks completed all possible contrasts (AB, BC and AC). Four of the 6 participants showed distinct preferences in these two-choice tests with indications of preference hierarchies. The results demonstrate a method for obtaining indications of relative preference for potentially reinforcing stimuli from individuals without communication and without the abilities to act on more than one switch

Teaching Individuals to Signal for Assistance in a Timely Manner

This is the peer reviewed version of the following article: Saunders, M. D., & Saunders, R. R. (2012). Teaching Individuals to Signal for Assistance in a Timely Manner. Behavioral Interventions : Theory & Practice in Residential & Community-Based Clinical Programs, 27(4), 10.1002/bin.1346. http://doi.org/10.1002/bin.1346, which has been published in final form at doi.org/10.1002/bin.1346. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingThe study describes the adaptive-switch performances of 8 adults with severe multiple impairments. Each was given a series of progressively more difficult discrimination tasks that, if solved, would require the participant to close the switch to activate a device that was not operating or to stay away from the switch if the device was operating. Then in a 2-choice format, a preference test was conducted by providing 2 devices simultaneously that could be activated or deactivated by closure or release of the switch. Finally, a preferred device was activated and then surreptitiously deactivated. Switch closures in this contingency activated a speech-generating device that played the message, “Help me.” All 8 participants learned to control devices using their adaptive switch, but only 4 participants learned to make a request for help. Reasons for the different performances across learners and nonlearners are discussed

Person-related and Treatment-related Barriers to Alcohol Treatment

Treatment underutilization by persons with alcohol use disorder is well-documented. This study examined barriers to treatment at the latter stages of the treatment-seeking process, which was conceptualized as recognizing the problem, deciding that change is necessary, deciding that professional help is required, and seeking care. All participants identified themselves as having a drinking problem that was severe enough to warrant treatment. Differences between those who had (Treatment Seekers) and those who had not (Comparison Controls) sought treatment were evaluated, including the experience of person-related (e.g., shame) and treatment-related (e.g., cost) barriers. Person-related barriers were more commonly endorsed by both groups than treatment-related barriers. Comparison Controls were more likely to endorse both types of barriers, especially the preference for handling the problem without treatment. Treatment-related barriers were less relevant than person-related barriers at the latter stage of help seeking. The significance of barriers endured after accounting for other differences, such as drinking-related negative consequences. Treatment implications are discussed

A new camera for high-resolution infrared imaging of works of art

A new camera – SIRIS (scanning infrared imaging system) – developed at the National Gallery in London allows high-resolution images to be made in the near infrared region (900–1700 nm). The camera is based on a commercially available 320 × 256 pixel indium gallium arsenide area array sensor. This relatively small sensor is moved across the focal plane of the camera using two orthogonal translation stages to give images of c. 5000 × 5000 pixels. The main advantages of the SIRIS camera over scanning infrared devices or sequential image capture and mosaic assembly are its comparative portability and rapid image acquisition – making a 5000 × 5000 pixel image takes less than 20 minutes. The SIRIS camera can operate at a range of resolutions; from around 2.5 pixels per millimetre over an area of up to 2 × 2 m to 10 pixels per millimetre when examining an area measuring 0.5 × 0.5 m. The development of the mechanical, optical and electronic components of the camera, including the design of a new lens, is described. The software used to control image capture and to assemble the individual frames into a seamless mosaic image is mentioned. The camera was designed primarily to examine underdrawings in paintings; preliminary results from test targets and paintings imaged in situ are presented and the quality of the images compared with those from other cameras currently used for this application

SIRIS: a high resolution scanning infrared camera for examining paintings

The new SIRIS (Scanning InfraRed Imaging System) camera developed at the National Gallery in London allows highresolution images of paintings to be made in the near infrared region (900–1700 nm). Images of 5000 × 5000 pixels are made by moving a 320 × 256 pixel InGaAs array across the focal plane of the camera using two orthogonal translation stages. The great advantages of this camera over scanning infrared devices are its relative portability and that image acquisition is comparatively rapid – a full 5000 × 5000 pixel image can be made in around 20 minutes. The paper describes the development of the mechanical, optical and electronic components of the camera, including the design of a new lens. The software routines used to control image capture and to assemble the individual 320 × 256 pixel frames into a seamless mosaic image are also mentioned. The optics of the SIRIS camera have been designed so that the camera can operate at a range of resolutions; from around 2.5 pixels per millimetre on large paintings of up to 2000 × 2000 mm to 10 pixels per millimetre on smaller paintings or details of paintings measuring 500 × 500 mm. The camera is primarily designed to examine underdrawings in paintings; preliminary results from test targets and paintings are presented and the quality of the images compared with those from other cameras currently used in this field

South African Corporations and post-Apartheid Expansion in Africa – creating a new regional space

The defeat of Apartheid in 1994 liberated not only South Africa’s internal political processes but also its economic relations with neighbouring countries in the Southern African Development Community (SADC). A key outcome was the surge of South African capital northward after years of dampened large scale investment because of legal sanction and more informal regulation. By the early 2000s, South African mining and industrial corporations, financial institutions and even some medium-sized enterprises have once again asserted their role as a dominant force in the SADC region. South Africa’s economic expansion is sometimes portrayed as a one-way process, where local environments and communities are passive recipients of SouthAfrican-led interventions. But evidence increasingly suggests that penetration of the region is highly contested by host countries, and sometimes actively and effectively resisted at local level. In other words, elements of both ‘sub-imperialism’ and local subversion are at play

Establishing a Conditional Signal for Assistance in Teenagers with Blindness

Five teenagers with severe intellectual impairments and no discernible communication skills were enrolled in training to teach a conditional request for assistance using a speech-generating device (SGD). All were either blind or severely visually impaired since birth. All learned to operate an adaptive switch to control sensory outcomes, next showed preferences among sensory outcomes, and then demonstrated the ability to use their switch to signal for assistance with an SGD when the sensory outcome was remotely disabled. During the signaling phase, or subsequent attempts to generalize its use outside the laboratory, 3 participants began vocalizing. Most notably, they began imitation of the word “song” or the word “help” emitted by the SGD. The potential role of cause-and-effect training with adaptive switches is discussed

The temperature dependence of photo-elastic properties of cross-linked amorphous polyethylenes

Cross-linked samples of polyethylene were prepared by electron irradiation of both high and low density polymers in the crystalline state. A further cross-linked sample was obtained by curing a high density polyethylene by reaction with dicumyl peroxide at 180°C. The stress-strain birefringence relations were obtained, on specimens cut from these samples, at temperatures between 130 and 250°C. All samples showed a substantial decrease in stress-optical coefficient with increasing degree of cross-linking and with increasing temperature. The stress-optical properties at each temperature were extrapolated to zero degree of cross-linking to give quantities characteristic of the Guassian network. Comparison of these properties with Gaussian theory of the network leads to a value of ca.1150 cals/mole for the difference in energy between trans and gauche conformations of successive links of the polyethylene chain and also indicates that the optical anisotropy of a - CH2 group in the elastomeric state is more nearly given by Denbigh’s than by Bunn and Daubeny's polaris-abilities