1,451 research outputs found

    Observation of the Curie Transition in Palladium Bionanomaterial Using Muon Spin Rotation Spectroscopy

    Get PDF
    Palladium bionanomaterial was manufactured using the sulfate-reducing bacterium, Desulfovibrio desulfuricans, to reduce soluble Pd(II) ions to cell-bound Pd(0). The material was examined using a Superconducting Quantum Interference Device (SQUID) to observe bulk magnetisation over the temperature range 10 – 300 K and by Muon Spin Rotation (μSR), which is a probe of the local magnetic environment inside the sample, over the temperature range 200 – 700 K. Results from SQUID were used to model the temperature dependence of ferromagnetic and paramagnetic components of the bulk magnetisation and, by extrapolation, to predict the Curie transition temperature. Results from μSR confirmed the accuracy of the prediction to within 20 K. The Curie transition, which started at 528 K, was shown to be spread over a wide ( 100 K) range. This was attributed to dependence of the transition on particle size and the range of particle sizes in the population. A competing contribution to the overall magnetisation was observed due to partial thermal decomposition of the organic component of the material. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3533

    Kaon Electromagnetic Production on Nuclei

    Get PDF
    The formation and excitation of hypernuclei through kaon photoproduction is reviewed. Basic features of the production process are emphasized. The possibility of extracting new information on hypernuclear structure and on the wave function of the bound Λ\Lambda is discussed. New results are presented for the quasifree production process A(γ,KΛ)BA(\gamma, K \Lambda)B. Observables of this reaction are shown to be sensitive to the Λ\Lambda-nucleus final state interaction.Comment: 10 pages, 4 figures. Invited talk given at the International Conference on Hypernuclear and Strange Particle Physics (HYP97), Brookhaven National Laboratory, USA, October 13-18, 1997. To be published in Nucl. Phys.

    A within farm clinical trial to compare two treatments (parenteral antibacterials and hoof trimming) for sheep lame with footrot

    Get PDF
    From observational studies, farmers who use parenteral antibacterials to promptly treat all sheep with footrot (FR) or interdigital dermatitis (ID) have a prevalence of lameness of <2% compared with a prevalence of 9% lameness reported by farmers who treat lame sheep by trimming affected feet. We tested the hypothesis that prompt treatment of sheep lame with naturally developing FR or ID with parenteral and topical antibacterials reduces the prevalence and incidence of lameness with these conditions compared with less frequent treatment with trimming of hoof horn and applying topical antibacterials. A further hypothesis was that reduction of ID and FR would improve productivity. A lowland sheep flock with 700 ewes was used to test these hypotheses in an 18-month within farm clinical trial with four groups of ewes: two intervention and two control. The duration and severity of lameness was used to categorise sheep into three weighted scores of lameness (WLS): never lame (WLS0), mildly lame/lame for <6 days (WLS1) and severely or chronically lame (WLS2). The intervention reduced the prevalence of lameness due to FR and ID in ewes and lambs and the incidence of lameness in ewes. The WLS was also significantly lower in sheep in the intervention groups. Ewes with a higher WLS were subsequently significantly more likely to have a body condition score <2.5 and to have lame lambs. Significantly more ewes lambed and successfully reared more lambs that were ready for slaughter at a younger age in the intervention versus control groups. There was an increase in the gross margin of £630/100 ewes mated in the intervention group, including the cost of treatment of £150/100 ewes mated. We conclude that prompt parenteral and topical antibacterial treatment of sheep lame with ID and FR reduced the prevalence and incidence of these infectious conditions and led to improved health, welfare and productivity

    The Role of Friction in Compaction and Segregation of Granular Materials

    Full text link
    We investigate the role of friction in compaction and segregation of granular materials by combining Edwards' thermodynamic hypothesis with a simple mechanical model and mean-field based geometrical calculations. Systems of single species with large friction coefficients are found to compact less. Binary mixtures of grains differing in frictional properties are found to segregate at high compactivities, in contrary to granular mixtures differing in size, which segregate at low compactivities. A phase diagram for segregation vs. friction coefficients of the two species is generated. Finally, the characteristics of segregation are related directly to the volume fraction without the explicit use of the yet unclear notion of compactivity.Comment: 9 pages, 6 figures, submitted to Phys. Rev.

    Effectiveness and cost-effectiveness of daily all-over-body application of emollient during the first year of life for preventing atopic eczema in high-risk children (The BEEP trial): protocol for a randomised controlled trial.

    Get PDF
    BACKGROUND: Atopic eczema (AE) is a common skin problem that impairs quality of life and is associated with the development of other atopic diseases including asthma, food allergy and allergic rhinitis. AE treatment is a significant cost burden for health care providers. The purpose of the trial is to investigate whether daily application of emollients for the first year of life can prevent AE developing in high-risk infants (first-degree relative with asthma, AE or allergic rhinitis). METHODS: This is a protocol for a pragmatic, two-arm, randomised controlled, multicentre trial. Up to 1400 term infants at high risk of developing AE will be recruited through the community, primary and secondary care in England. Participating families will be randomised in a 1:1 ratio to receive general infant skin-care advice, or general skin-care advice plus emollients with advice to apply daily to the infant for the first year of life. Families will not be blinded to treatment allocation. The primary outcome will be a blinded assessment of AE at 24 months of age using the UK Working Party Diagnostic Criteria for Atopic Eczema. Secondary outcomes are other definitions of AE, time to AE onset, severity of AE (EASI and POEM), presence of other allergic diseases including food allergy, asthma and hay fever, allergic sensitisation, quality of life, cost-effectiveness and safety of the emollients. Subgroup analyses are planned for the primary outcome according to filaggrin genotype and the number of first-degree relatives with AE and other atopic diseases. Families will be followed up by online and postal questionnaire at 3, 6, 12 and 18 months with a face-to-face visit at 24 months. Long-term follow-up until 60 months will be via annual questionnaires. DISCUSSION: This trial will demonstrate whether skin-barrier enhancement through daily emollient for the first year of life can prevent AE from developing in high-risk infants. If effective, this simple and cheap intervention has the potential to result in significant cost savings for health care providers throughout the world by preventing AE and possibly other associated allergic diseases. TRIAL REGISTRATION: ISRCTN registry; ID: ISRCTN21528841 . Registered on 25 July 2014

    Agenda-Setting With Local and National Issues

    Full text link
    Three factors lead to the hypothesis that agenda-setting should be weaker at the local political level compared to the national level: (1) the more directly observable nature of local political problems, (2) the nature and strength of local interpersonal political communication networks, and (3) the relatively heavier media coverage of national political issues. This hypothesis was supported with data from respondents assigned at random to either local or national issue conditions and from a content analysis of television and newspaper coverage in Toledo, Ohio, of local and national issues. Contrary to the findings of certain previous studies, network television was found to exercise a stronger agenda-setting influence than newspapers at the national level. Newspapers, on the other hand, were the dominant agenda-setter at the local level. The relative agenda-setting influences of television versus newspapers are consistent with other data from this study concerning the relative strengths of the various media as sources of issue information.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67066/2/10.1177_009365027700400404.pd

    Resonances in the three-neutron system

    Full text link
    A study of 3-body resonances has been performed in the framework of configuration space Faddeev equations. The importance of keeping a sufficient number of terms in the asymptotic expansion of the resonance wave function is pointed out. We investigated three neutrons interacting in selected force components taken from realistic nn forces.Comment: 38 pages, 11 tables, 4 figure

    Dijet Rapidity Gaps in Photoproduction from Perturbative QCD

    Get PDF
    By defining dijet rapidity gap events according to interjet energy flow, we treat the photoproduction cross section of two high transverse momentum jets with a large intermediate rapidity region as a factorizable quantity in perturbative QCD. We show that logarithms of soft gluon energy in the interjet region can be resummed to all orders in perturbation theory. The resummed cross section depends on the eigenvalues of a set of soft anomalous dimension matrices, specific to each underlying partonic process, and on the decomposition of the scattering according to the possible patterns of hard color flow. We present a detailed discussion of both. Finally, we evaluate numerically the gap cross section and gap fraction and compare the results with ZEUS data. In the limit of low gap energy, good agreement with experiment is obtained.Comment: 37 pages, Latex, 17 figure
    corecore