11,432 research outputs found

    Improving water productivity: how do we get more crop from every drop

    Get PDF
    Water management / Productivity / Irrigation management / Supplemental irrigation / Crop production

    Variational Study of Weakly Coupled Triply Heavy Baryons

    Get PDF
    Baryons made of three heavy quarks become weakly coupled, when all the quarks are sufficiently heavy such that the typical momentum transfer is much larger than Lambda_QCD. We use variational method to estimate masses of the lowest-lying bcc, ccc, bbb and bbc states by assuming they are Coulomb bound states. Our predictions for these states are systematically lower than those made long ago by Bjorken.Comment: 31 pages, 5 figure

    No-scale D=5 supergravity from Scherk-Schwarz reduction of D=6 theories

    Get PDF
    We perform a generalized dimensional reduction of six dimensional supergravity theories to five dimensions. We consider the minimal (2,0)(2,0) and the maximal (4,4)(4,4) theories. In each case the reduction allows us to obtain gauged supergravities of no-scale type in dimension five with gauge groups that escape previous classifications. In the minimal case, the geometric data of the reduced theory correspond to particular cases of the D=5 real special geometry. In the maximal case we find a four parameter solution which allows partial breaking of supersymmetry.Comment: AMS-LaTeX 16 pages. A reference added, some minor changes performe

    Quantum Revivals in a Periodically Driven Gravitational Cavity

    Get PDF
    Quantum revivals are investigated for the dynamics of an atom in a driven gravitational cavity. It is demonstrated that the external driving field influences the revival time significantly. Analytical expressions are presented which are based on second order perturbation theory and semiclassical secular theory. These analytical results explain the dependence of the revival time on the characteristic parameters of the problem quantitatively in a simple way. They are in excellent agreement with numerical results

    Analog of Magnetoelectric Effect in High-Tc Granular Superconductors

    Full text link
    We propose the existence of an electric-field induced nonlinear magnetization in a weakly coupled granular superconductor due to time-parity violation. As the field increases the induced magnetization passes from para- to dia-magnetic behavior. We discuss conditions under which this effect could be experimentally measured in high-temperature superconductors.Comment: REVTEX (epsf style), 1 PS figure; to appear in Europhysics Letter

    Adaptation of international guidelines on assessment and management of cancer pain for the Australian context

    Get PDF
    Aim: To develop clinical practice guidelines for screening, assessing and managing cancer pain in Australian adults. Methods: This three phase project utilised the ADAPTE approach to adapt international cancer pain guidelines for the Australian setting. A Working Party was established to define scope, screen guidelines for adaptation, and develop recommendations to support better cancer pain control through screening, assessment, pharmacological and non-pharmacological management, and patient education. Recommendations with limited evidence were referred to Expert Panels for advice before the draft guidelines were opened for public consultation via the Cancer Council Australia Cancer Guidelines Wiki platform in late 2012. All comments were reviewed by the Working Party and the guidelines revised accordingly. Results: Screening resulted in six international guidelines being included for adaptation - those developed by the Scottish Intercollegiate Guidelines Network (2008), National Health Service Quality Improvement Scotland (2009), National Comprehensive Cancer Network (2012), European Society of Medical Oncology (2011), European Association for Palliative Care (2011, 2012) and National Institute of Clinical Excellence (2012). Guideline adaptation resulted in 55 final recommendations. The guidelines were officially launched in November 2013. Conclusion: International guidelines can be efficiently reconfigured for local contexts using the ADAPTE approach. Availability of the guidelines via the Cancer Council Australia Wiki is intended to promote uptake and enable recommendations to be kept up to date. Resources to support implementation will also be made available via the Wiki if found to be effective by a randomised controlled trial commencing in 2015

    Valuing improvements in the water rights system in South Africa : a contingent ranking approach

    Get PDF
    In the context of increasing water scarcity, understanding is growing that irrigation water rights are important and that a lack of effective water rights systems constitute a major reason for inefficient water management. This study carried out a contingent ranking experiment to study how smallholder irrigators in South Africa would value potential changes in water rights. Three specific dimensions of water rights, relevant for the South African case, are considered: duration, quality of title and transferability. Results indicate that smallholder irrigators are prepared to pay considerably higher water prices if improvements are made in the water rights system. This implies that the proposed interventions in the water rights system would improve the efficiency and productivity of the small-scale irrigation sector. The increased willingness to pay could furthermore also assist South African government to reach the objective of increased cost recovery

    Direct mode summation for the Casimir energy of a solid ball

    Full text link
    The Casimir energy of a solid ball placed in an infinite medium is calculated by a direct frequency summation using the contour integration. It is assumed that the permittivity and permeability of the ball and medium satisfy the condition ϵ1μ1=ϵ2μ2\epsilon_1 \mu_1=\epsilon_2\mu_2. Upon deriving the general expression for the Casimir energy, a dilute compact ball is considered (ϵ1ϵ2)2/(ϵ1+ϵ2)21(\epsilon_1 -\epsilon_2)^2/(\epsilon_1+\epsilon_2)^2\ll 1. In this case the calculations are carried out which are of the first order in ξ2\xi ^2 and take account of the five terms in the Debye expansion of the Bessel functions involved. The implication of the obtained results to the attempts of explaining the sonoluminescence via the Casimir effect is shortly discussed.Comment: REVTeX, 7 pages, no figures and tables, treatment of a dilute dielectric ball is revised, new references are adde

    Spatial aspects of oncogenic signalling determine the response to combination therapy in slice explants from Kras-driven lung tumours

    Get PDF
    A key question in precision medicine is how functional heterogeneity in solid tumours informs therapeutic sensitivity. We demonstrate that spatial characteristics of oncogenic signalling and therapy response can be modelled in precision-cut slices from Kras-driven non-small-cell lung cancer with varying histopathologies. Unexpectedly, profiling of in situ tumours demonstrated that signalling stratifies mostly according to histopathology, showing enhanced AKT and SRC activity in adenosquamous carcinoma, and mitogen-activated protein kinase (MAPK) activity in adenocarcinoma. In addition, high intertumour and intratumour variability was detected, particularly of MAPK and mammalian target of rapamycin (mTOR) complex 1 activity. Using short-term treatment of slice explants, we showed that cytotoxic responses to combination MAPK and phosphoinositide 3-kinase-mTOR inhibition correlate with the spatially defined activities of both pathways. Thus, whereas genetic drivers determine histopathology spectra, histopathology-associated and spatially variable signalling activities determine drug sensitivity. Our study is in support of spatial aspects of signalling heterogeneity being considered in clinical diagnostic settings, particularly to guide the selection of drug combinations
    corecore