Make it so! Jean-Luc Picard, Bart Simpson and the design of e-public services

In this paper, we report on a project applying participatory design methods to include people who have experience of social exclusion (in one form or another) in designing possible technologies for e-(local)-government services. The work was part of a project for the Office of the Deputy Prime Minister in the UK, and was concerned with ‘access tokens’ that can provide personal identification for individuals accessing public services, based on technologies such as multi-functional smartcards, flash memory sticks, mobile phone SIMs or similar devices. In particular we report on our experience using the ‘pastiche scenarios’ technique recently developed by Mark Blythe. Our findings indicate that the technique can be effective and engaging in helping people to create realistic scenarios of future technology use and highlight some possible pitfalls to consider when using this technique.</p

Resonant States in the Electronic Structure of the High Performance Thermoelectrics AgPbmSbTe_{m}SbTe_{2+m}$ ; The Role of Ag-Sb Microstructures

Ab initio electronic structure calculations based on gradient corrected density functional theory were performed on a class of novel quaternary compounds AgPb$_{m}SbTe$_{2+m}$, which were found to be excellent high temperature thermoelctrics with large figure of merit ZT ~2.2 at 800K. We find that resonant states appear near the top of the valence and bottom of the conduction bands of bulk PbTe when Ag and Sb replace Pb. These states can be understood in terms of modified Te-Ag(Sb) bonds. Electronic structure near the gap depends sensitively on the microstructural arrangements of Ag-Sb atoms, suggesting that large ZT values may originate from the nature of these ordering arrangements.Comment: Accepted in Physical Review Letter

Cage-size control of guest vibration and thermal conductivity in Sr8Ga16Si30-xGex

We present a systematic study of thermal conductivity, specific heat, electrical resistivity, thermopower and x-ray diffraction measurements performed on single-crystalline samples of the pseudoquaternary type-I clathrate system Sr8Ga16Si30-xGex, in the full range of 0 < x < 30. All the samples show metallic behavior with n-type majority carriers. However, the thermal conductivity and specific heat strongly depend on x. Upon increasing x from 0 to 30, the lattice parameter increases by 3%, from 10.446 to 10.726 A, and the localized vibrational energies of the Sr guest ions in the tetrakaidekahedron (dodecahedron) cages decrease from 59 (120) K to 35 (90) K. Furthermore, the lattice thermal conductivity at low temperatures is largely suppressed. In fact, a crystalline peak found at 15 K for x = 0 gradually decreases and disappears for x > 20, evolving into the anomalous glass-like behavior observed for x = 30. It is found that the increase of the free space for the Sr guest motion directly correlates with a continuous transition from on-center harmonic vibration to off-center anharmonic vibration, with consequent increase in the coupling strength between the guest's low-energy modes and the cage's acoustic phonon modes.Comment: 7 pages, 7 figures, submitted to PR

Glasslike vs. crystalline thermal conductivity in carrier-tuned Ba8Ga16X30 clathrates (X = Ge, Sn)

The present controversy over the origin of glasslike thermal conductivity observed in certain crystalline materials is addressed by studies on single-crystal x-ray diffraction, thermal conductivity k(T) and specific heat Cp(T) of carrier-tuned Ba8Ga16X30 (X = Ge, Sn) clathrates. These crystals show radically different low-temperature k(T) behaviors depending on whether their charge carriers are electrons or holes, displaying the usual crystalline peak in the former case and an anomalous glasslike plateau in the latter. In contrast, Cp(T) above 4 K and the general structural properties are essentially insensitive to carrier tuning. We analyze these combined results within the framework of a Tunneling/Resonant/Rayleigh scatterings model, and conclude that the evolution from crystalline to glasslike k(T) is accompanied by an increase both in the effective density of tunnelling states and in the resonant scattering level, while neither one of these contributions can solely account for the observed changes in the full temperature range. This suggests that the most relevant factor which determines crystalline or glasslike behavior is the coupling strength between the guest vibrational modes and the frameworks with different charge carriers.Comment: 8 pages, 4 figures, 4 tables, submitted to Phys. Rev.

Glass-Like Heat Conduction in High-Mobility Crystalline Semiconductors

The thermal conductivity of polycrystalline semiconductors with type-I clathrate hydrate crystal structure is reported. Ge clathrates (doped with Sr and/or Eu) exhibit lattice thermal conductivities typical of amorphous materials. Remarkably, this behavior occurs in spite of the well-defined crystalline structure and relatively high electron mobility ($\sim 100 cm^2/Vs$). The dynamics of dopant ions and their interaction with the polyhedral cages of the structure are a likely source of the strong phonon scattering.Comment: 4 pages, 3 postscript figures, to be published, Phys. Rev. Let

Haemophilus influenzae type b disease in the era of conjugate vaccines: critical factors for successful eradication

Introduction: Prior to implementation of Haemophilus influenzae type b (Hib)-conjugate vaccination programs in the 1990s, Hib was the commonest cause of bacterial meningitis in children aged &lt;5&nbsp;years. While the burden of all Hib disease has significantly decreased in the post-vaccination era, Hib still accounted for &gt;29,000 deaths worldwide in children aged &lt;5&nbsp;years in 2015. Areas covered: We reviewed literature data on the most widely used Hib vaccines and vaccination strategies which led to the global prevention and control of Hib disease and aim to highlight important factors for continued disease control and elimination in the future. Expert commentary: More than 90% of countries worldwide have implemented Hib-conjugate vaccination in their national immunization programs. Vaccines containing Hib polyribosylribitol phosphate (PRP) conjugated with tetanus toxoid (Hib-TT) are the most commonly used. Neisseria meningitidis outer membrane protein complex of PRP (Hib-OMP) is also used. Although the kinetics of the immune response varies with Hib vaccine and schedule used, high control of Hib disease was observed in all settings/scenarios. Further improving global Hib vaccination coverage may result in disease elimination. Plain language summary: What is the context? Haemophilus influenzae is causing a variety of diseases, from otitis media and sinusitis to invasive disease (e.g. meningitis and pneumonia). H. influenzae type b (Hib) was the most common cause of bacterial meningitis in children &lt;5 years of age, and especially among &lt;2-year-olds. Even with appropriate treatment, up to 40% of children with bacterial meningitis can suffer permanent disabilities and up to 5% will die. The development of vaccines to protect against Hib disease has started in the late 1970s and has culminated with the licensure of 4 Hib conjugate vaccines, of which 2 are currently widely used. What is new? In this review, we gathered evidence on the different Hib vaccines and vaccination strategies that have contributed to the global prevention and control of Hib disease. The review indicates: the incidence of Hib disease has decreased considerably due to the introduction of Hib vaccines in national immunization programs worldwide. However, Hib disease is not yet completely eradicated. the vaccines currently used offer protection against Hib over long periods of time. carriage of the pathogen by healthy individuals seem to be less frequent, but data are still needed to fully evaluate the impact of vaccination. other H. influenzae types are now more frequent. Why is this important? Despite the huge success of Hib vaccination, continuous surveillance is needed to anticipate potential re-emergences and devise the best strategies for prevention and control of disease. Hib vaccination should be considered in the few countries who have not yet implemented it, to decrease associated morbidity and mortality

Neonatal pain detection in videos using the iCOPEvid dataset and an ensemble of descriptors extracted from Gaussian of Local Descriptors

Diagnosing pain in neonates is difficult but critical. Although approximately thirty manual pain instruments have been developed for neonatal pain diagnosis, most are complex, multifactorial, and geared toward research. The goals of this work are twofold: 1) to develop a new video dataset for automatic neonatal pain detection called iCOPEvid (infant Classification Of Pain Expressions videos), and 2) to present a classification system that sets a challenging comparison performance on this dataset. The iCOPEvid dataset contains 234 videos of 49 neonates experiencing a set of noxious stimuli, a period of rest, and an acute pain stimulus. From these videos 20 s segments are extracted and grouped into two classes: pain (49) and nopain (185), with the nopain video segments handpicked to produce a highly challenging dataset. An ensemble of twelve global and local descriptors with a Bag-of-Features approach is utilized to improve the performance of some new descriptors based on Gaussian of Local Descriptors (GOLD). The basic classifier used in the ensembles is the Support Vector Machine, and decisions are combined by sum rule. These results are compared with standard methods, some deep learning approaches, and 185 human assessments. Our best machine learning methods are shown to outperform the human judges

Paedophiles in the community: inter-agency conflict, news leaks and the local press

This article explores the leaking of confidential information about secret Home Office plans to house convicted paedophiles within a local community (albeit inside a prison). It argues that a politics of paedophilia has emerged in which inter-agency consensus on the issue of ‘what to do’ with high-profile sex offenders has broken down. Accordingly, the article situates newspaper ‘outing’ of paedophiles in the community in relation to vigilante journalism and leaked information from official agencies. The article then presents research findings from a case study of news events set in train following a whistle-blowing reaction by Prison Officers’ Association officials to Home Office plans. Drawing from a corpus of 10 interviews with journalists and key protagonists in the story, the article discusses both the dynamics of whistle blowing about paedophiles and also what happens after the whistle has blown