The syntheses, structures, and N2 adsorption properties of six new supramolecular metallacycles are reported. Flexible ditopic linkers, 1-4, with systematically varied lengths and conformational degrees of freedom were synthesized utilizing ester linkages. They were used in combination with (dppp)M(OTf)2, where M = Pt(II) and Pd(II), and cis-(Me3P)2Pt(OTf)2 to form flexible supramolecular metallacycles 5-10 in 88-98% isolated yields. Their structures were characterized via multinuclear NMR and X-ray crystallography. The metallacycles stack to form porous structures in the crystalline state. The pore dimensions depend on both the phosphorus ligands attached to the metals and the flexible linkers. Adsorption studies on the porous materials show that 5a, 6, 8, and 9 held 11.7, 16.5, 5.7, and 6.8 cm3/g STP of N2 at 77 K, respectively. A guest-exchange study with nitromethane and toluene reveals that the nanopore in 5 is flexible, a property which was transferred from the linker to the supramolecular structure in the solid state.

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We have tested the potential of three types of vibration motors for use in a tactile vision substitution device for the blind. The motors were of the coin type, which are available off-the-shelf, and are characterized by their affordability, energy efficiency, and ease of implementation. The primary limitation of coin motors is the lack of control they offer over stimulus parameters. Specifically, adjusting the input voltage of a coin motor not only changes the vibration intensity, but also the vibration frequency and duration. This characteristic may result in unpredictable perceptions in psychophysical tests. By using standard psychophysical procedures, we were able to show that the tested coin motors evoked predictable magnitude perceptions across their dynamic range, following Fechner's law as if vibration intensity alone were varied. The best-performing motor was able to generate a median number of 15 available just-noticeable differences, meaning that it was potentially capable of conveying 16 gray levels in its dynamic range. We conclude that coin motors are potential candidates for the construction of a tactile display to substitute for lost vision.

Background: Despite potential savings to the National Health Service, the collection of data on outcomes of NHS orthotic services is patchy. Indeed, several reports into orthotic services in the UK have reported a lack of data relating to outcomes of care and highlighted the need to routinely measure outcomes to demonstrate efficacy of services. Whilst a previous study provided an overview of the use of outcome measures in orthotic practice and identified some barriers to their use, further questions emerged. Hence, this qualitative study aimed to explore orthotists' opinions and personal experiences on the influences on outcomes, how appropriate and relevant outcomes can be measured and also how barriers to the use of outcome measures can be overcome. Methods: Following a review of the literature, an initial advisory group informed semi-structured questions. These were used to create dialogue in a focus group of 12 orthotists. Data from the focus group was transcribed verbatim and analysed using thematic analysis, creating themes and subthemes for discussion. Results: The setting of realistic and agreed goals through managing expectations, compromise and patient education/information were seen as factors that could inform and improve outcomes. Barriers to the collection of outcome measures were associated with inadequate technology to manage the data, lack of time to complete them, lack of training in them and difficulties selecting appropriate outcome measures for patients with complex problems managed by different health professionals. The participants discussed ways of addressing these barriers, such as the use of 'snapshots' and delegation of data collection. Conclusions: This study has revealed that measuring outcomes is considered to be an important activity. In order to achieve good outcomes, it is important to address patient expectations, discuss and establish joint goals for care at the outset and inform and include patients in the decision-making process. The identified barriers to measuring outcomes can be overcome with the solutions revealed by these participants. Hence, this study has contributed to current knowledge which has relevance for clinical practice and may provide the theoretical basis for future research.

Initial results obtained with a simple, fully automated algorithm for detection of left ventricular boundaries are presented. The strength of this approach is the use of dynamic programming search techniques, which allow determination of local border points to be influenced by the entire global border location. The relative contributions of mask mode subtraction and the dynamic search technique are evaluated with respect to accurate border definition. These computer-determined ventricular borders are compared with hand-traced borders on subtracted and unsubtracted images. The modular dynamic search algorithm is shown to perform better than previously described algorithms, which generally require operator interaction. It is also shown that for both manual and automated techniques, ventricular borders derived from subtracted images may be significantly different from borders derived from nonsubtracted images.

Tactile vision substitution devices are assistive devices for the blind that redirect visual information to the skin. The amount of visual information that can be presented on a tactile display is limited mainly by the spatial resolution of the skin and the ability to distinguish between various vibration intensities. In this study, we have determined the two-point discrimination (TPD) threshold and intensity-discrimination threshold (just-noticeable difference, or JND) on the lower back using coin motors. Given the importance of stimulus timing, we have determined TPD threshold and JND at different stimulus onset asynchronies (SOAs). The JND was determined between two coin motors with a distance equal to the TPD threshold. In this way, we could establish the contrast sensitivity at the maximal theoretical resolution. TPD thresholds tended to decrease at longer SOAs, from 52 mm edge-to-edge at an SOA of 0 ms, to 28 mm at 200 ms. The JND did not depend on SOA, and the average Weber fraction was 0.14. A median of 5 JNDs was available across the available dynamic range. Together, these data provide the predicted spatial resolution and contrast resolution achievable with a back-worn tactile display based on coin motors.

Tactile vision substitution devices are assistive technologies for the blind that redirect visual information to the tactile sense. They typically include a tactile display that conveys visual information to the skin. Two important parameters that determine the maximum information bandwidth of tactile displays are the spatial acuity of the skin, and the ability of the user to discriminate between stimulus intensities. These two parameters were investigated by determining the two-point discrimination (TPD) threshold and the just-noticeable intensity difference (JND) using coin motors on the lower back. Coin motors are eccentric rotating-mass motors that are affordable, energy-efficient, and easy to implement. The lower back was chosen because it is a discreet place to wear assistive technology. It is generally available for use, as it is usually not critically involved in activities of daily living. Rehabilitation with sensory substitution devices often requires training by professional occupational therapists, because the user needs to extract visual information from sparse information presented through an alternative channel such as the skin. In this study they determined whether short, automated training sessions of 5 min each could improve the TPD threshold and JND. It was found that 10 min of computer-assisted training improved the vibrotactile TPD threshold on the lower back by 36%, and that 18 min of training improved the just-noticeable intensity difference (JND) by 44%. It was concluded that short, automated training sessions could provide a fast and inexpensive means to improve people's basic spatial acuity and intensity discrimination skills with coin motors.