Impact perforation testing of stab-resistant armour materials

This paper describes the development of a method for the investigation and comparison of materials for use in stab resistant body armour. A number of polymer composite panels of different thicknesses and construction have been tested. A dynamic test which simulated the real threat has been used and the results compared to a simpler quasi-static test that might be used in initial materials selection. The materials tested were glass-epoxy, and glass-nylon composite panels of several thicknesses between 1.8 and 5.8mm. Additional tests were also performed on similar composites containing tungsten wires. An accelerated instrumented drop-tower was used to drive a knife through composite panels and record the force resisting penetration by the knife. The final penetration of the knife through the armour into a soft backing was also measured. For comparison,a similar geometry quasi-static test was carried out on the same specimens. It was found that energy absorbtion took the form of an initial resistance to perforation and then by a resistance to further penetration. This is thought to stem from resistance to cutting ofthe panel material and gripping of the knife blade. The energy required to produce a given penetration in dynamic tests was found to be in good agreement with the penetration achieved at similar energies under quasi-static conditions. For the materials tested there was no significant difference between the penetration resistance of single or two layer systems. The penetration achieved through a panel of a given material was approximately proportional to the inverse square of the panel's thickness. The relative performance of different armour materials was assessed by plotting the energy required to penetrate a fixed distance against the areal density of the panel

Incommensurate Spin Density Waves in Iron Aluminides

Neutron diffraction in Fe(Al) reveals incommensurate spin density waves (SDWs) in alloys known to be spin glasses. The wave vectors for crystals of Fe(34Al), Fe(40Al), and Fe(43Al) show n varying from 11 to 6 for →q=2π(h±1/n,k±1/n,l±1/n)/a0, where (h,k,l) and a0 characterize the parent bcc lattice of the CsCl structure. The magnetic reflections are present far above the spin-glass freezing temperatures. These SDWs keep the spins on nearest-neighbor Fe atoms close to parallel, in contrast with SDWs in Cr, which keep nearest-neighbor spins close to antiparallel

The Serums Tool-Chain:Ensuring Security and Privacy of Medical Data in Smart Patient-Centric Healthcare Systems

Digital technology is permeating all aspects of human society and life. This leads to humans becoming highly dependent on digital devices, including upon digital: assistance, intelligence, and decisions. A major concern of this digital dependence is the lack of human oversight or intervention in many of the ways humans use this technology. This dependence and reliance on digital technology raises concerns in how humans trust such systems, and how to ensure digital technology behaves appropriately. This works considers recent developments and projects that combine digital technology and artificial intelligence with human society. The focus is on critical scenarios where failure of digital technology can lead to significant harm or even death. We explore how to build trust for users of digital technology in such scenarios and considering many different challenges for digital technology. The approaches applied and proposed here address user trust along many dimensions and aim to build collaborative and empowering use of digital technologies in critical aspects of human society

Depinning transition in type-II superconductors

The surface impedance Z(f) of conventional isotropic materials has been carefully measured for frequencies f ranging from 1 kHz to 3 MHz, allowing a detailed investigation of the depinning transition. Our results exhibit the irrelevance of classical ideas to the dynamics of vortex pinning. We propose a new picture, where the linear ac response is entirely governed by disordered boundary conditions of a rough surface, whereas in the bulk vortices respond freely. The universal law for Z(f) thus predicted is in remarkable agreement with experiment, and tentatively applies to microwave data in YBaCuO films.Comment: 4 pages, 4 figures, 14 reference

Whole-Genome Sequencing and Concordance Between Antimicrobial Susceptibility Genotypes and Phenotypes of Bacterial Isolates Associated with Bovine Respiratory Disease.

Extended laboratory culture and antimicrobial susceptibility testing timelines hinder rapid species identification and susceptibility profiling of bacterial pathogens associated with bovine respiratory disease, the most prevalent cause of cattle mortality in the United States. Whole-genome sequencing offers a culture-independent alternative to current bacterial identification methods, but requires a library of bacterial reference genomes for comparison. To contribute new bacterial genome assemblies and evaluate genetic diversity and variation in antimicrobial resistance genotypes, whole-genome sequencing was performed on bovine respiratory disease-associated bacterial isolates (Histophilus somni, Mycoplasma bovis, Mannheimia haemolytica, and Pasteurella multocida) from dairy and beef cattle. One hundred genomically distinct assemblies were added to the NCBI database, doubling the available genomic sequences for these four species. Computer-based methods identified 11 predicted antimicrobial resistance genes in three species, with none being detected in M. bovis While computer-based analysis can identify antibiotic resistance genes within whole-genome sequences (genotype), it may not predict the actual antimicrobial resistance observed in a living organism (phenotype). Antimicrobial susceptibility testing on 64 H. somni, M. haemolytica, and P. multocida isolates had an overall concordance rate between genotype and phenotypic resistance to the associated class of antimicrobials of 72.7% (P < 0.001), showing substantial discordance. Concordance rates varied greatly among different antimicrobial, antibiotic resistance gene, and bacterial species combinations. This suggests that antimicrobial susceptibility phenotypes are needed to complement genomically predicted antibiotic resistance gene genotypes to better understand how the presence of antibiotic resistance genes within a given bacterial species could potentially impact optimal bovine respiratory disease treatment and morbidity/mortality outcomes

Materializing digital collecting: an extended view of digital materiality

If digital objects are abundant and ubiquitous, why should consumers pay for, much less collect them? The qualities of digital code present numerous challenges for collecting, yet digital collecting can and does occur. We explore the role of companies in constructing digital consumption objects that encourage and support collecting behaviours, identifying material configuration techniques that materialise these objects as elusive and authentic. Such techniques, we argue, may facilitate those pleasures of collecting otherwise absent in the digital realm. We extend theories of collecting by highlighting the role of objects and the companies that construct them in materialising digital collecting. More broadly, we extend theories of digital materiality by highlighting processes of digital material configuration that occur in the pre-objectification phase of materialisation, acknowledging the role of marketing and design in shaping the qualities exhibited by digital consumption objects and consequently related consumption behaviours and experiences

Experiential aspects of tourism gift consumption

This article addresses how consumers make use of fantasy, feelings, and fun when deciding, giving, and consuming gifts of tourism and leisure. Despite little industry awareness, consumers are engaging with such behaviour because tourism gifts offer considerable scope for the creative expression of donor–recipient relationships. This UK-based interpretive qualitative study captured data from donors, recipients, and tourism and leisure providers. The feelings (emotions), fantasies (imagination and dreaming), and fun (playfulness) were interrogated through the behavioural phases of gift decision making, gift exchange, post-exchange, and gift consumption. A range of emotions were displayed by donors and recipients at different stages in the gift-giving process; donor decision making in groups for created gifts was particularly charged. Fantasies were evident both for donors planning gifts and for recipients. As an intangible gift, means of exchange allowed for creative mechanisms beyond the classic wrapping strategies associated with physical gifts. The ‘decoy’ strategy stimulated the recipient’s imagination to conjure fantastical scenarios. Fun or playfulness was built into many of the gifts and often related to an element of ‘surprise’, an attribute of the perfect gift (e.g. Belk, 1996) in Western societies

Electrodynamics of a Clean Vortex Lattice

We report on a microscopic evaluation of electrodynamic response for the vortex lattice state of a model s-wave superconductor. Our calculation accounts self-consistently for both quasiparticle and order parameter response and establishes the collective nature of linear response in the clean limit. We discuss the effects of homogeneous and inhomogeneous pinning on the optical conductivity and the penetration depth, and comment on the relationship between macroscopic and local penetration depths. We find unexpected relationships between pinning arrangements and conductivity due to the strongly non-local response.Comment: 4 pages, 2 figure

Prime beef cuts : culinary images for thinking 'men'

The paper contributes to scholarship theorising the sociality of the brand in terms of subject positions it makes possible through drawing upon the generative context of circulating discourses, in this case of masculinity, cuisine and celebrity. Specifically, it discusses masculinity as a socially constructed gender practice (Bristor and Fischer, 1993), examining materialisations of such practice in the form of visualisations of social relations as resources for 'thinking gender' or 'doing gender'. The transformative potential of the visualisations is illuminated by exploring the narrative content choreographed within a series of photographic images positioning the market appeal of a celebrity chef through the medium of a contemporary lifestyle cookery book. We consider how images of men 'doing masculinity'are not only channelled into reproducing existing gender hierarchy and compulsory heterosexuality in the service of commercial ends, but also into disrupting such enduring stereotyping through subtle reframing. We acknowledge that masculinity is already inscribed within conventionalised representations of culinary culture. In this case we consider how traces of masculinity are exploited and reinscribed through contemporary images that generate resources for rethinking masculine roles and identities, especially when viewed through the lens of stereotypically feminised pursuits such as shopping, food preparation, cooking, and the communal intimacy of food sharing. We identify unsettling tensions within the compositions, arguing that they relate to discursive spaces between the gendered positions written into the images and the popular imagination they feed off. Set against landscapes of culinary culture, we argue that the images invoke a brand of naively roughish "laddishness" or "blokishness", rendering it in domesticated form not only as benign and containable, but fashionable, pliable and, importantly, desirable. We conclude that although the images draw on stereotypical premeditated notions of a feral, boisterous and untamed heterosexual masculinity, they also set in motion gender-blending narratives