Unreliable numbers: error and harm induced by bad design can be reduced by better design

Number entry is a ubiquitous activity and is often performed in safety- and mission-critical procedures, such as healthcare, science, finance, aviation and in many other areas. We show that Monte Carlo methods can quickly and easily compare the reliability of different number entry systems. A surprising finding is that many common, widely used systems are defective, and induce unnecessary human error. We show that Monte Carlo methods enable designers to explore the implications of normal and unexpected operator behaviour, and to design systems to be more resilient to use error. We demonstrate novel designs with improved resilience, implying that the common problems identified and the errors they induce are avoidable.     

NMR spectroscopy of human post mortem cerebrospinal fluid: distinction of Alzheimer''s disease from control using pattern recognition and statistics

Mutations of ras oncogenes in 37 human stomach cancers and 13 adenomas were investigated with regard to the histological phenotypes using polymerase chain reaction (PCR), allele-specific oligonucleotide hybridization and/or direct sequencing of the PCR products. The ras mutation was found only in one case (2.7%), the histology of which was poorly differentiated adenocarcinoma. We found no mutation in stomach adenomas. The mutation consisted of a guanine-to-adenine transition in the first base of codon 13 of c-Ki-ras which replaced wild-type glycine with serine, indicating that a putative glycine-to-aspartic acid change is not necessarily the critical event for c-Ki-ras gene activation in codon 13. These results further confirm the infrequency of ras mutation in stomach tumors and also suggest that ras mutations are not specific to the differentiated type of stomach cancer.     

Inhibition of gene expression by steroid hormone receptors via a negative glucocorticoid response element: evidence for the involvement of DNA-binding and agonistic effects of the antiglucocorticoid/antiprogestin RU486

We have used a negative glucocorticoid response element (nGRE) from the bovine prolactin promoter linked to the gene for chloramphenicol acetyltransferase (PRL3CAT) to study the inhibition of gene expression by steroid hormone receptors. This nGRE increased basal expression from a heterologous promoter in COS-7 cells. In the presence of cotransfected glucocorticoid (GR), androgen, or progesterone receptor (PR) expression vectors and their cognate ligands, the expression of PRL3CAT could be repressed, indicating that these steroid receptor subfamily members could function through the same negative response element. No repression was observed with the estrogen receptor, showing that the repressive effect was specific for members of the GR-subfamily. Mutation of three amino acids within the GR-DNA binding domain that determine the specificity of GR-GRE interaction abolished the ability of the GR to inhibit the expression of PRL3CAT, demonstrating the requirement for DNA binding of the GR in the mechanism of repression. The antiglucocorticoid/antiprogestin RU486 when bound to PR or GR also repressed the expression of the PRL3CAT, but higher concentrations of RU486 were required to obtain an effect with the GR when compared to the PR. RU486 was unable to antagonize the effect of progestins on PRL3CAT and only partially antagonized the glucocorticoid repression. Thus, regarding the repression of PRL3CAT, RU486 acted as an agonist when bound to the PR and as a partial agonist when bound to the GR.     

Immersive electronic books for surgical training

Immersive electronic books (IEBooks) for surgical training will let surgeons explore previous surgical procedures in 3D. The authors describe the techniques and tools for creating a preliminary IEBook, embodying some of the basic concepts.     

Evaluation of four steering wheels to determine driver hand placement in a static environment

While much research exists on occupant packaging both proprietary and in the literature, more detailed research regarding user preferences for subjective ratings of steering wheel designs is sparse in published literature. This study aimed to explore the driver interactions with production steering wheels in four vehicles by using anthropometric data, driver hand placement, and driver grip design preferences for Generation-Y and Baby Boomers. In this study, participants selected their preferred grip diameter, responded to a series of questions about the steering wheel grip as they sat in four vehicles, and rank ordered their preferred grip design. Thirty-two male participants (16 Baby Boomers between ages 47 and 65 and 16 Generation-Y between ages 18 and 29) participated in the study. Drivers demonstrated different gripping behavior between vehicles and between groups. Recommendations for future work in steering wheel grip design and naturalistic driver hand positioning are discussed.     

Comments on the use of buckminsterfullerene encapsulated in zeolite Y as a potential catalyst

Buckminsterfullerene encapsulated within zeolite Y is found not to be a reactive radical initiator for the formation of dimethoxyethane from dimethyl ether below 200° C. Above this temperature the expected acid catalysed conversion of dimethyl ether to hydrocarbons is observed. Dimethoxyethane formation is observed when bibenzoyl peroxide is used as a radical initiator. These studies indicate that any radical formed by the encapsulated buckminsterfullerene is relatively unreactive.     

A new type of ozone generator using Taylor cones on water surfaces

Ozone has been found to be effective in many forms of water treatment. As concerns about the safety of alternate methods of water treatment increase (in particular, chlorination), ozone, which is already extensively used in Europe, offers an effective option. This paper describes a new method of ozone generation particularly suited for use in water purification. Most current industrial ozone production is based on “silent” electrical discharges in a gap between concentric electrodes separated by a glass or ceramic dielectric barrier. The authors present experimental results obtained using a parallel-plate discharge geometry. The lower electrode consists of a grounded “pool” of still water separated by a discharge gap from an upper insulated planar electrode. When the electrode is energized by an AC high voltage, a multitude of “Taylor cones” forms on the water surface. The Taylor cones form and collapse randomly and continuously, depending on the electric field. The tips of the cones provide points for electrical discharge pulses which initiate ozone generation. This method generates ozone in close proximity to the water surface. Laboratory experiments show efficiencies for gaseous ozone production as high as 110 g/kWh     

Adapting computer data storage to user group behaviour

We have designed several interactive computer systems for financial analysts. In early designs we treated the analysts-computer interactive dialogue at a computer terminal as being isolated from group considerations. In a later system we were forced to make extensive technical changes to take account of data storage sharing. This sharing of data storage had to operate in a way which was consistent with existing group attitudes. The relevant features of this system are described, and reviewed after more than two years of operation. We conclude that many user-computer interactive dialogues cannot be designed as if they were 'private' to a single user, but must be considered in a wider context of the way in which members of a user group interact.     

Minimum required angular resolution of smartphone displays for the human visual system

There has been a rapid increase in the resolution of small‐sized and medium‐sized displays. This study determines an upper discernible limit for display resolution. A range of resolutions varying from 254–1016 PPI were evaluated using simulated display by 49 subjects at 300 mm viewing distance. The results of the study conclusively show that users can discriminate between 339 and 508 PPI and in many cases between 508 and 1016 PPI.     

Investigating different factor structures of the Psychopathy Checklist: Youth version: Confirmatory factor analytic findings.

There has been a recent push to extend the construct of psychopathy into adolescence, primarily as a result of the impressive reliability, validity, and utility of this construct in samples of adults. The value of this work rests, however, on creating an equally reliable and valid assessment tool for adolescents. One promising measure is the Psychopathy Checklist: Youth Version (A. E. Forth, D. S. Kosson, & R. D. Hare, 2003). The current study uses a large, diverse sample of serious adolescent offenders to assess the overall fit of various underlying factor structures of this measure and to test the equivalence of these models across sex and race/ethnicity. The results suggest that either a 3- or 4-factor model provides the best overall fit and that these models are invariant across sex and race/ethnicity. The decision to use the 3- or 4-factor model will likely hinge on researchers' underlying conceptualization of psychopathy, specifically whether antisocial behavior is viewed as a core feature of this construct. (PsycINFO Database Record (c) 2010 APA, all rights reserved)