An interface to virtual environments for people who are blind using Wii technology - mental models and navigation

Accessible games, both for serious and for entertainment purposes, would allow inclusion and participation for those with disabilities. Research into the development of accessible games, and accessible virtual environments, is discussed. Research into accessible Virtual Environments has demonstrated great potential for allowing people who are blind to explore new spaces, reducing their reliance on guides, and aiding development of more efficient spatial maps and strategies. Importantly, Lahav and Mioduser (2005, 2008) have demonstrated that, when exploring virtual spaces, people who are blind use more and different strategies than when exploring real physical spaces, and develop relatively accurate spatial representations of them. The present paper describes the design, development and evaluation of a system in which a virtual environment may be explored by people who are blind using Nintendo Wii devices, with auditory and haptic feedback. The nature of the various types of feedback is considered, with the aim of creating an intuitive and usable system. Using Wii technology has many advantages, not least of which are that it is mainstream, readily available and cheap. The potential of the system for exploration and navigation is demonstrated. Results strongly support the possibilities of the system for facilitating and supporting the construction of cognitive maps and spatial strategies. Intelligent support is discussed. Systems such as the present one will facilitate the development of accessible games, and thus enable Universal Design and accessible interactive technology to become more accepted and widespread

Ignition of flammable hydrogen/air mixtures by high mass mechanical impact of Magnox contaminated surfaces

Magnox and its corrosion products are a major constituent of some legacy nuclear waste storage silos which generate hydrogen. An experimental study investigates the likelihood of ignition of hydrogen/air when large mass projectiles impact rusty surfaces with Magnox contamination. Ignition is observed with 50kg projectiles impacting a 45º Magnox-smeared rusty anvil plate with KE as low as 40J. Theoretical calculations relating to the angled impacts reveal that they involve substantial tangential energy losses associated with frictional heating of the impact surfaces. It is shown that these energy losses are particularly dependent on the shape of the projectile since projectile geometry determines the radius of gyration and the relationship of centre of gravity to the impact point. In conclusion, the projectile shape is likely to be of greater importance than the mass (i.e. for a given impact energy) because of its direct bearing on the magnitude of the tangential energy loss

Improving the Supply Distribution and Use of Antimalarial Drugs by the Private Sector in Tanzania. Report prepared for the National Malaria Control Programme, United Republic of Tanzania

Private pharmacies or shops are the source of 60% of the drugs bought to treat suspected cases of malaria. At the same time 59% of children fail to be treated within 24 hours of onset. The private sector is the primary source for antimalarials, but parents and carers are failing to administer those drugs sufficiently early to minimise morbidity and mortality. This review focused on the way in which antimalarial drugs reach the patient. It also examined ways in which the delivery system could be improved and how the private facilities can become more effective sources of both drugs and advice. It has found that there are many problems with the way that drugs are distributed. Many unregistered drugs are readily available, and poor storage conditions are likely to reduce the efficacy of drugs even if they were of good quality at the time of manufacture. For many people the cost of even the cheapest antimalarial is an issue and purchase of part doses is common. The knowledge of the staff in pharmacies is poor and in shops woefully inadequate. Nonetheless most people use shops and private pharmacies as their source for drugs. There are two overarching requirements: • First of all the needs and capabilities of the private sector must always be taken into account before any decision is made about how to make antimalarials more available. • Secondly, educating the staff and public will only be achieved through a subtle communications package regularly repeated and brought up to date. For example we found that many workers in Part II pharmacies remain in post for no more than one year. Unlike their counterparts in the public sector, staff in the private sector do not find incentives in attending training courses. Staff in the public sector spend so much time on courses that their time to actually implement what they have learned is limited. To reach the private sector staff will require subtler and more cost effective methods. The report is full of detailed recommendations for the improvement of the supply systems and for educating both staff and public

Specific antibodies against vaccine-preventable infections: a mother-infant cohort study

OBJECTIVES: To determine maternal and neonatal specific antibody levels to selected vaccine-preventable infections (pertussis, Haemophilus influenzae type b (Hib), tetanus and pneumococcus). DESIGN: Prospective cohort study. SETTING: A UK secondary care maternity unit (March 2011-January 2012). PARTICIPANTS: Mothers and infants within 72 h of delivery were eligible. Unwell individuals, mothers less than 18 years of age, and infants born at less than 36 weeks gestation, or weighing less than 2500 g, were excluded. HIV-infected mothers were included. 112 mother-infant pairs were recruited. Samples from 111 mothers and 109 infants (108 pairs) were available for analysis. OUTCOME MEASURES: Specific antibody levels were determined using standard commercial ELISAs. Specific antibody to pertussis antigens (PT and FHA) of >50 IU/ml, defined as 'positive' by the test manufacturer, were interpreted as protective. Antitetanus antibody titres >0.1 IU/ml and anti-Hib antibody titres >1 mg/l were regarded as protective. RESULTS: Only 17% (19/111) of women exhibited a protective antibody response against pertussis. 50% (56/111) of women had levels of antibody protective against Hib and 79% (88/111) against tetanus. There was a strong positive correlation between maternal-specific and infant-specific antibodies' responses against pertussis (rs=0.71, p<0.001), Hib (rs=0.80, p<0.001), tetanus (rs=0.90, p<0.001) and pneumococcal capsular polysaccharide (rs=0.85, p<0.001). Only 30% (33/109) and 42% (46/109) of infants showed a protective antibody response to pertussis and Hib, respectively. Placental transfer (infant:mother ratio) of specific IgG to pertussis, Hib, pneumococcus and tetanus was significantly reduced from HIV-infected mothers to their HIV-exposed, uninfected infants (n=12 pairs) compared with HIV-uninfected mothers with HIV-unexposed infants (n=96 pairs) by 58% (<0.001), 61% (<0.001), 28% (p=0.034) and 32% (p=0.035), respectively. CONCLUSIONS: Low baseline antibody levels against pertussis in this cohort suggest the recently implemented UK maternal pertussis immunisation programme has potential to be effective

Characterizing precursors to stellar clusters with Herschel

Context. Despite their profound effect on the universe, the formation of massive stars and stellar clusters remains elusive. Recent advances in observing facilities and computing power have brought us closer to understanding this formation process. In the past decade, compelling evidence has emerged that suggests infrared dark clouds (IRDCs) may be precursors to stellar clusters. However, the usual method for identifying IRDCs is biased by the requirement that they are seen in absorption against background mid-IR emission, whereas dust continuum observations allow cold, dense pre-stellar-clusters to be identified anywhere. Aims: We aim to understand what dust temperatures and column densities characterize and distinguish IRDCs, to explore the population of dust continuum sources that are not IRDCs, and to roughly characterize the level of star formation activity in these dust continuum sources. Methods: We use Hi-GAL 70 to 500 $m data to identify dust continuum sources in the ell = 30deg and ell = 59deg Hi-GAL science demonstration phase (SDP) fields, to characterize and subtract the Galactic cirrus emission, and perform pixel-by-pixel modified blackbody fits on cirrus-subtracted Hi-GAL sources. We utilize archival Spitzer data to indicate the level of star-forming activity in each pixel, from mid-IR-dark to mid-IR-bright. Results: We present temperature and column density maps in the Hi-GAL ell = 30deg and ell = 59deg SDP fields, as well as a robust algorithm for cirrus subtraction and source identification using Hi-GAL data. We report on the fraction of Hi-GAL source pixels which are mid-IR-dark, mid-IR-neutral, or mid-IR-bright in both fields. We find significant trends in column density and temperature between mid-IR-dark and mid-IR-bright pixels; mid-IR-dark pixels are about 10 K colder and have a factor of 2 higher column density on average than mid-IR-bright pixels. We find that Hi-GAL dust continuum sources span a range of evolutionary states from pre- to star-forming, and that warmer sources are associated with more star formation tracers. Additionally, there is a trend of increasing temperature with tracer type from mid-IR-dark at the coldest, to outflow/maser sources in the middle, and finally to 8 and 24$m bright sources at the warmest. Finally, we identify five candidate IRDC-like sources on the far-side of the Galaxy. These are cold (20 K), high column density (N(H$_2$) gt 10$^22$ cm$^-2$) clouds identified with Hi-GAL which, despite bright surrounding mid-IR emission, show little to no absorption at 8 $m. These are the first inner Galaxy far-side candidate IRDCs of which the authors are aware. Herschel in an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation by NASA.The FITS files discussed in the paper would be released publicly WITH the Hi-GAL data (on the Hi-GAL website) when the Hi-GAL data is released publicly.Peer reviewe

THE COMPARISON OF PHYSICAL PROPERTIES DERIVED FROM GAS AND DUST IN A MASSIVE STAR-FORMING REGION

We explore the relationship between gas and dust in a massive star-forming region by comparing the physical properties derived from each. We compare the temperatures and column densities in a massive star-forming Infrared Dark Cloud (G32.02+0.05), which shows a range of evolutionary states, from quiescent to active. The gas properties were derived using radiative transfer modeling of the (1,1), (2,2), and (4,4) transitions of NH3 on the Karl G. Jansky Very Large Array, while the dust temperatures and column densities were calculated using cirrus-subtracted, modified blackbody fits to Herschel data. We compare the derived column densities to calculate an NH3 abundance, χ$_{{\rm NH}_{3}}$ = 4.6 × 10–8. In the coldest star-forming region, we find that the measured dust temperatures are lower than the measured gas temperatures (mean and standard deviations T dust, avg ~ 11.6 ± 0.2 K versus T gas, avg ~ 15.2 ± 1.5 K), which may indicate that the gas and dust are not well-coupled in the youngest regions (~0.5 Myr) or that these observations probe a regime where the dust and/or gas temperature measurements are unreliable. Finally, we calculate millimeter fluxes based on the temperatures and column densities derived from NH3, which suggest that millimeter dust continuum observations of massive star-forming regions, such as the Bolocam Galactic Plane Survey or ATLASGAL, can probe hot cores, cold cores, and the dense gas lanes from which they form, and are generally not dominated by the hottest core

Potential hazard consequences to personnel exposed to the ignition of small volumes of weakly confined stoichiometric hydrogen/air mixture

Many studies have been devoted to understanding the consequence of ignition events that could occur as a result of using hydrogen as an alternative to fossil fuels or when hydrogen is present in large scale industrial or nuclear waste sites. Little attention has however, been given to the effect of explosion in small scale operations: this could involve service work with manual handling and manipulation of gas containing packages or vessels. The purpose of this study is to begin to address this knowledge gap and report the results of an experimental program carried out to simulate the effect of localised and weakly confined small volume hydrogen explosions on personal safety. Three aspects of personal injury consequences are considered; injury from shock loading to the head/brain, skin burns and acoustic/hearing damage. It is concluded from ignition and acoustic noise exposure experiments, carried with stoichiometric hydrogen /air mixtures, that injuries arising from shock loading or burns to the skin are less likely than hearing damage. It is suggested that further work should focus on the noise exposure and hearing damage effects of small scale explosions