2,080 research outputs found

    Self reported aggravating activities do not demonstrate a consistent directional pattern in chronic non specific low back pain patients: An observational study

    Get PDF
    Question: Do the self-reported aggravating activities of chronic non-specific low back pain patients demonstrate a consistent directional pattern? Design: Cross-sectional observational study. Participants: 240 chronic non specific low back pain patients. Outcome measure: We invited experienced clinicians to classify each of the three self-nominated aggravating activities from the Patient Specific Functional Scale by the direction of lumbar spine movement. Patients were described as demonstrating a directional pattern if all nominated activities moved the spine into the same direction. Analyses were undertaken to determine if the proportion of patients demonstrating a directional pattern was greater than would be expected by chance. Results: In some patients, all tasks did move the spine into the same direction, but this proportion did not differ from chance (p = 0.328). There were no clinical or demographic differences between those who displayed a directional pattern and those who did not (all p > 0.05). Conclusion: Using patient self-reported aggravating activities we were unable to demonstrate the existence of a consistent pattern of adverse movement in patients with chronic non-specific low back pain

    Optimising Agronomic Options At The Farm Scale

    Get PDF
    Strategic planning and policy development for environmentally sustainable and economically viable management options for the rice based farming systems require the assessment of management options using mathematical models which integrate our understanding of water and salt movement with economic considerations at both the farm and regional scales. This project also had strong links with LWRRDC/MIL/CSIRO project on optimising irrigation intensities in the Murray Valley. During this project a standalone farm scale hydrological economic model SWAGMAN Farm (Salt Water and Groundwater MANagement) was developed and customised for situations in the Coleambally and Murray Irrigation Areas. The model processes were developed and refined by using feed back from irrigation managers, regulators and community groups. The following major achievements have been made: · Collection of crop, soil, irrigation, climatic and economic data sets for fourteen farms in the Murray Irrigation Districts · Rigorous validation of model processes by applying the model to fourteen farms with a range of enterprise, soil and groundwater conditions. · Development of simulation and optimisation modes in SWAGMAN Farm to assess environmental and economic impacts of existing and optimal cropping patterns · Various improvements of water and salt balance processes to suit conditions in the Murray Districts and the Coleambally Irrigation Area · Incorporation of soil water content accounting which provides flexibility in the representation of various starting soil profile water content conditions, water availability to crops and rational computation of recharge and watertable rise during the cropping and fallow periods · Development of a Windows based GAMS independent version of SWAGMAN Farm. GAMS (General Algebraic Modelling System) was an expensive software platform for the previous version with inflexible licence requirements. The new version written in C++ language uses Microsoft Access databases and will be linked with a GIS interface in near future. These sensitivity runs and model developments gained the confidence of members of the steering committee who provided vital inputs throughout this project. While considerable progress was made, they see the need for the work to continue to the stage where it can be applied to assist strategic planning and policy development, taking into account local regional conditions. Parallel to the modelling project an intensive paddock water monitoring project titled “Rigorously determined water balance benchmarks for irrigated crops and pasture’ was also initiated by the steering committee with the assistance of CSIRO, MIL, NSW Agriculture and LWRRDC. The purpose of the monitoring project was to further customise SWAGMAN Farm to local conditions and to validate the model results with the field data. Since monitoring projects take significant time in setting up and calibrating equipment, data analysis has only recently started, however initial comparisons of model results with the field results suggest that the improved SWAGMAN Farm can reasonably simulate field situations. However this work needs to continue to maximise the benefits of the paddock water balance monitoring. However, due to the wide range of groundwater, enterprise and soil conditions in the irrigation areas, SWAGMAN Farm needs to be applied to every farm to develop soundly based policy options. The need for application to individual farms is further driven by the complex regional groundwater interactions causing reversal (downward to upward and local discharge zones) of leakage rates in parts of the irrigation areas e.g. Murray Valley. This project has demonstrated that it is possible to develop methodology which helps assess optimal irrigation intensity within a multitude of biophysical and socio-economic constraints. The methods developed have scientific validity in capturing and representing key processes, and have community acceptance as a way of examining options that are important to them

    Amplitudes and Spinor-Helicity in Six Dimensions

    Get PDF
    The spinor-helicity formalism has become an invaluable tool for understanding the S-matrix of massless particles in four dimensions. In this paper we construct a spinor-helicity formalism in six dimensions, and apply it to derive compact expressions for the three, four and five point tree amplitudes of Yang-Mills theory. Using the KLT relations, it is a straightforward process to obtain amplitudes in linearized gravity from these Yang-Mills amplitudes; we demonstrate this by writing down the gravitational three and four point amplitudes. Because there is no conserved helicity in six dimensions, these amplitudes describe the scattering of all possible polarization states (as well as Kaluza-Klein excitations) in four dimensions upon dimensional reduction. We also briefly discuss a convenient formulation of the BCFW recursion relations in higher dimensions.Comment: 26 pages, 2 figures. Minor improvements of the discussio

    Diversity of gut microflora is required for the generation of B cell with regulatory properties in a skin graft model

    Get PDF
    B cells have been reported to promote graft rejection through alloantibody production. However, there is growing evidence that B cells can contribute to the maintenance of tolerance. Here, we used a mouse model of MHC-class I mismatched skin transplantation to investigate the contribution of B cells to graft survival. We demonstrate that adoptive transfer of B cells prolongs skin graft survival but only when the B cells were isolated from mice housed in low sterility "conventional" (CV) facilities and not from mice housed in pathogen free facilities (SPF). However, prolongation of skin graft survival was lost when B cells were isolated from IL-10 deficient mice housed in CV facilities. The suppressive function of B cells isolated from mice housed in CV facilities correlated with an anti-inflammatory environment and with the presence of a different gut microflora compared to mice maintained in SPF facilities. Treatment of mice in the CV facility with antibiotics abrogated the regulatory capacity of B cells. Finally, we identified transitional B cells isolated from CV facilities as possessing the regulatory function. These findings demonstrate that B cells, and in particular transitional B cells, can promote prolongation of graft survival, a function dependent on licensing by gut microflora

    Targeted insertion of an anti-CD2 monoclonal antibody transgene into the GGTA1 locus in pigs using FokI-dCas9

    Get PDF
    Xenotransplantation from pigs has been advocated as a solution to the perennial shortage of donated human organs and tissues. CRISPR/Cas9 has facilitated the silencing of genes in donor pigs that contribute to xenograft rejection. However, the generation of modified pigs using second-generation nucleases with much lower off-target mutation rates than Cas9, such as FokI-dCas9, has not been reported. Furthermore, there have been no reports on the use of CRISPR to knock protective transgenes into detrimental porcine genes. In this study, we used FokI-dCas9 with two guide RNAs to integrate a 7.1 kilobase pair transgene into exon 9 of the GGTA1 gene in porcine fetal fibroblasts. The modified cells lacked expression of the αGal xenoantigen, and secreted an anti-CD2 monoclonal antibody encoded by the transgene. PCR and sequencing revealed precise integration of the transgene into one allele of GGTA1, and a small deletion in the second allele. The cells were used for somatic cell nuclear transfer to generate healthy male knock-in piglets, which did not express αGal and which contained anti-CD2 in their serum. We have therefore developed a versatile high-fidelity system for knocking transgenes into the pig genome for xenotransplantation purposes.Mark B. Nottle, Evelyn J. Salvaris, Nella Fisicaro, Stephen McIlfatrick, Ivan Vassiliev, Wayne J. Hawthorne, Philip J. O’Connell, Jamie L. Brady, Andrew M. Lew and Peter J. Cowa

    Quasi-elastic and inelastic inclusive electron scattering from an oxygen jet target

    Full text link
    The results of an experiment on inclusive electron scattering from an oxygen jet target, performed in a wide range of energy and momentum transfer covering both quasi-elastic and Δ\Delta(1232) resonance regions, are reported. In the former region the theoretical predictions, obtained including effects of nucleon-nucleon correlations in both initial and final states, give a good description of the experimental data. In the inelastic region a broadening as well as a damping of the resonant part of the cross section with respect to the free nucleon case is observed. The need of more detailed calculations including nuclear structure effects on the electroproduction cross section of nucleon resonances is highlighted.Comment: to appear in Nucl. Phys.

    Far-Ultraviolet Radiation from Elliptical Galaxies

    Get PDF
    Far-ultraviolet radiation is a ubiquitous, if unanticipated, phenomenon in elliptical galaxies and early-type spiral bulges. It is the most variable photometric feature associated with old stellar populations. Recent observational and theoretical evidence shows that it is produced mainly by low-mass, small-envelope, helium-burning stars in extreme horizontal branch and subsequent phases of evolution. These are probably descendents of the dominant, metal rich population of the galaxies. Their lifetime UV outputs are remarkably sensitive to their physical properties and hence to the age and the helium and metal abundances of their parents. UV spectra are therefore exceptionally promising diagnostics of old stellar populations, although their calibration requires a much improved understanding of giant branch mass loss, helium enrichment, and atmospheric diffusion.Comment: 46 pages; includes LaTeX text file, 9 PS figures, 1 JPG figure, 2 style files. Full resolution figures and PS version available at http://www.astro.virginia.edu/~rwo/araa99/. Article to appear in Annual Reviews of Astronomy & Astrophysics, 199
    corecore