Acoustic characterization of crack damage evolution in sandstone deformed under conventional and true triaxial loading

We thank the Associate Editor, Michelle Cooke, and the reviewers, Ze'ev Reches and Yves Guéguen, for useful comments which helped to improve the manuscript. We thank J.G. Van Munster for providing access to the true triaxial apparatus at KSEPL and for technical support during the experimental program. We thank R. Pricci for assistance with technical drawings of the apparatus. This work was partly funded by NERC award NE/N002938/1 and by a NERC Doctoral Studentship, which we gratefully acknowledge. Supporting data are included in a supporting information file; any additional data may be obtained from J.B. (e-mail: [email protected]).Peer reviewedPublisher PD

Signal specific electric potential sensors for operation in noisy environments

Limitations on the performance of electric potential sensors are due to saturation caused by environmental electromagnetic noise. The work described involves tailoring the response of the sensors to reject the main components of the noise, thereby enhancing both the effective dynamic range and signal to noise. We show that by using real-time analogue signal processing it is possible to detect a human heartbeat at a distance of 40 cm from the front of a subject in an unshielded laboratory. This result has significant implications both for security sensing and biometric measurements in addition to the more obvious safety related applications

Feasibility of targeted early detection for melanoma: a population-based screening study

The feasibility of targeted screening for cutaneous malignant melanoma in the UK using a postal questionnaire and invitation to screening by a consultant dermatologist was investigated in a population based cross-sectional survey. A total of 1600 people aged 25–69 years, stratified by the social deprivation score of wards within one general practice, were randomly selected from a population of 8000.1227 (77%) returned the questionnaire and 896 (56%) attended the screening clinic. Uptake was lower for men (P< 0.001), those aged under 50 (P< 0.001), people from deprived areas (P< 0.001) and skin types III and IV (men only, P< 0.001). Twenty per cent of women and 10% of men felt nervous about attending the clinic, but only 4% were worried by the questionnaire. The level of agreement between the self- and dermatologist's assessments of risk factors was best for hair colour (Kappa = 0.67, sensitivity 73% and specificity 98%). People tended to under-report their level of risk. Over 95% knew about at least one major sign, but 54% reported incorrect signs of melanoma. Targeted screening for melanoma in the UK will be hampered by difficulties in accurately identifying the target population. Strategies to improve skin self-awareness rather than screening should be developed and evaluated. © 2000 Cancer Research Campaig

Homogeneous heterotic supergravity solutions with linear dilaton

I construct solutions to the heterotic supergravity BPS-equations on products of Minkowski space with a non-symmetric coset. All of the bosonic fields are homogeneous and non-vanishing, the dilaton being a linear function on the non-compact part of spacetime.Comment: 36 pages; v2 conclusion updated and references adde

Accelerated gene evolution and subfunctionalization in the pseudotetraploid frog Xenopus laevis

Ancient whole genome duplications have been implicated in the vertebrate and teleost radiations, and in the emergence of diverse angiosperm lineages, but the evolutionary response to such a perturbation is still poorly understood. The African clawed frog Xenopus laevis experienced a relatively recent tetraploidization {approx} 40 million years ago. Analysis of the considerable amount of EST sequence available for this species together with the genome sequence of the related diploid Xenopus tropicalis provides a unique opportunity to study the genomic response to whole genome duplication

An inside story: tracking experiences, challenges and successes in a joint specialist performing arts college

In England the government’s specialist schools initiative is transforming the nature of secondary education. A three-year longitudinal case study tracked the effects of specialist performing arts college status on two schools. The sites were a mainstream school drawing pupils from an area of high social deprivation and disadvantage, and a special school catering for pupils with profound and \ud multiple learning difficulties, which were awarded joint performing arts college status. The government’s \ud preferred criterion for judging the success of specialist schools is improvement in whole-school examination results. The authors argue that this is a crude and inappropriate measure for these case study schools and probably others. Using questionnaires, interviews and documentation they tell an ‘inside story’ of experiences, challenges and achievements, from the perspectives of the schools’ mangers, staff and pupils. Alternative ‘value-added’ features emerged that were positive indicators of enrichment and success in both schools

The wool proteome and fibre characteristics of three distinct genetic ovine breeds from Portugal

Wool properties and commodity value vary considerably between breeds. In Portugal, three major ovine groups exist: Churros, Bordaleiros and Merinos. This work studies the effect of the ovine genotype on the wool proteome of such groups. Wool was collected from 15 ewes/breed and genetic groups: Churra da Terra Quente (CTQ) or Churro, Serra da Estrela (SE) or Bordaleiro and Merino Branco (MB) or Merino. Proteins were extracted and subjected to label-free proteomics analysis. A total of 50 keratinous protein groups were identified in all the samples, divided into type I and II keratins and the keratin associated proteins: high-glycine-tyrosine proteins, ultra-high sulphur proteins and high-sulphur proteins. Major differences were found between MB and CTQ with respect to K75 and K38, both medullar proteins and to a lesser extent between SE and CTQ suggesting that these might be good markers for this trait in wool. Partial least squares discriminatory analysis proved MB to be readily distinguishable from the other two breeds. Further differences were noted in keratin associated protein levels between the three breeds, normally an indicator of higher levels of orthocortex and also their relationship to high curvature, high crimp fibres like Merinoinfo:eu-repo/semantics/acceptedVersio

Xenopus tropicalis egg extracts provide insight into scaling of the mitotic spindle

The African clawed frog Xenopus laevis has been instrumental to investigations of both development and cell biology, but the utility of this model organism for genetic and proteomic studies is limited by its long generation time and unsequenced pseudotetraploid genome. Xenopus tropicalis, which is a small, faster-breeding relative of X. laevis, has recently been adopted for research in developmental genetics and functional genomics, and has been chosen for genome sequencing. We show that X. tropicalis egg extracts reconstitute the fundamental cell cycle events of nuclear formation and bipolar spindle assembly around exogenously added sperm nuclei. Interestingly, X. tropicalis spindles were ∼30% shorter than X. laevis spindles, and mixing experiments revealed a dynamic, dose-dependent regulation of spindle size by cytoplasmic factors. Measurements of microtubule dynamics revealed that microtubules polymerized slower in X. tropicalis extracts compared to X. laevis, but that this difference is unlikely to account for differences in spindle size. Thus, in addition to expanding the range of developmental and cell biological experiments, the use of X. tropicalis provides novel insight into the complex mechanisms that govern spindle morphogenesis