228 research outputs found

    Phase Dynamics of Nearly Stationary Patterns in Activator-Inhibitor Systems

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    The slow dynamics of nearly stationary patterns in a FitzHugh-Nagumo model are studied using a phase dynamics approach. A Cross-Newell phase equation describing slow and weak modulations of periodic stationary solutions is derived. The derivation applies to the bistable, excitable, and the Turing unstable regimes. In the bistable case stability thresholds are obtained for the Eckhaus and the zigzag instabilities and for the transition to traveling waves. Neutral stability curves demonstrate the destabilization of stationary planar patterns at low wavenumbers to zigzag and traveling modes. Numerical solutions of the model system support the theoretical findings

    Identifying Residents Who May Benefit from an Analgesic Review: Applying Analgesic Indicators in Residential Aged Care Services.

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    Background Ensuring safe and effective analgesic use in residential aged care services is important because older adults are susceptible to analgesic-related adverse drug events (ADEs). Objective The aim of this study was to identify the proportion and characteristics of residents of aged care services who may benefit from analgesic review based on indicators in the 2021 Society for Post-Acute and Long-Term Care Medicine (AMDA) Pain Management Guideline. Methods Cross-sectional analyses of baseline data from the Frailty in Residential Sector over Time (FIRST) study (N = 550 residents) across 12 South Australian residential aged care services in 2019 were conducted. Indicators included the proportion of residents who received > 3000 mg/day of acetaminophen (paracetamol), regular opioids without a documented clinical rationale, opioid doses > 60 mg morphine equivalents (MME)/day, more than one long-acting opioid concurrently, and a pro re nata (PRN) opioid on more than two occasions in the previous 7 days. Logistic regression was performed to investigate factors associated with residents who may benefit from analgesic review. Results Of 381 (69.3%) residents charted regular acetaminophen, 176 (46.2%) were charted > 3000 mg/day. Of 165 (30%) residents charted regular opioids, only 2 (1.2%) had no prespecified potentially painful conditions in their medical record and 31 (18.8%) received > 60 MME/day. Of 153 (27.8%) residents charted long-acting opioids, 8 (5.2%) received more than one long-acting opioid concurrently. Of 212 (38.5%) residents charted PRN opioids, 10 (4.7%) received more than two administrations in the previous 7 days. Overall, 196 (35.6%) of 550 residents were identified as potentially benefiting from analgesic review. Females (odds ratio [OR] 1.87, 95% confidence interval [CI] 1.20–2.91) and residents with prior fracture (OR 1.62, 95% CI 1.12–2.33) were more likely to be identified. Observed pain (OR 0.50, 95% CI 0.29–0.88) was associated with a lower likelihood of being identified compared with residents with no observed pain. Overall, 43 (7.8%) residents were identified based on opioid-related indicators. Conclusions Up to one in three residents may benefit from a review of their analgesic regimen, including 1 in 13 who may benefit from a specific review of their opioid regimen. Analgesic indicators represent a new approach to target analgesic stewardship interventions.Laura A. Dowd, Amanda J. Cross, Shin J. Liau, Agathe D. Jadczak, Renuka Visvanathan, Felicity C. Veal, J. Simon Bel

    Disorder and relaxation mode in the lattice dynamics of PbMg1/3_{1/3}Nb2/3_{2/3}O3_3 relaxor ferroelectric

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    The low-energy part of vibration spectrum in PbMg1/3_{1/3}Nb2/3_{2/3}O3_3 relaxor ferroelectric was studied by inelastic neutron scattering. We observed the coexistence of a resolution-limited central peak with strong quasielastic scattering. The line-width of the quasielastic component follows a Γ0+Dq2\Gamma_0+Dq^2 dependence. We find that Γ0\Gamma_0 is temperature-dependent. The relaxation time follows the Arrhenius law well. The presence of a relaxation mode associated with quasi-elastic scattering in PMN indicates that order-disorder behaviour plays an important r\^ole in the dynamics of diffuse phase transitions

    Studies of Phase Turbulence in the One Dimensional Complex Ginzburg-Landau Equation

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    The phase-turbulent (PT) regime for the one dimensional complex Ginzburg-Landau equation (CGLE) is carefully studied, in the limit of large systems and long integration times, using an efficient new integration scheme. Particular attention is paid to solutions with a non-zero phase gradient. For fixed control parameters, solutions with conserved average phase gradient ν\nu exist only for ν|\nu| less than some upper limit. The transition from phase to defect-turbulence happens when this limit becomes zero. A Lyapunov analysis shows that the system becomes less and less chaotic for increasing values of the phase gradient. For high values of the phase gradient a family of non-chaotic solutions of the CGLE is found. These solutions consist of spatially periodic or aperiodic waves travelling with constant velocity. They typically have incommensurate velocities for phase and amplitude propagation, showing thereby a novel type of quasiperiodic behavior. The main features of these travelling wave solutions can be explained through a modified Kuramoto-Sivashinsky equation that rules the phase dynamics of the CGLE in the PT phase. The latter explains also the behavior of the maximal Lyapunov exponents of chaotic solutions.Comment: 16 pages, LaTeX (Version 2.09), 10 Postscript-figures included, submitted to Phys. Rev.

    The microscopic spin-phonon coupling constants in CuGeO_3

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    Using RPA results, mean field theory, and refined data for the polarization vectors we determine the coupling constants of the four Peierls-active phonon modes to the spin chains of CuGeO_3. We then derive the values of the coupling of the spin system to the linear ionic displacements, the bond lengths and the angles between bonds. Our values are consistent with microscopic theories and various experimental results. We discuss the applicability of static approaches to the spin-phonon coupling. The c-axis anomaly of the thermal expansion is explained. We give the values of the coupling constants in an effective one-dimensional Hamiltonian.Comment: 11 pages, two figures, 13 tables, PRB 59 (in press

    SAHA-induced TRAIL-sensitisation of Multiple Myeloma cells is enhanced in 3D cell culture

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    Multiple Myeloma (MM) is currently incurable despite many novel therapies. Tumour Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) is a potential anti-tumour agent although effects as a single agent are limited. In this study, we investigated whether the Histone Deacetylase (HDAC) inhibitor SAHA can enhance TRAIL-induced apoptosis and target TRAIL resistance in both suspension culture, and 3D cell culture as a model of disseminated MM lesions that form in bone. The effects of SAHA and/or TRAIL in 6 Multiple Myeloma cell lines were assessed in both suspension cultures and in an Alginate-based 3D cell culture model. The effect of SAHA and/or TRAIL was assessed on apoptosis by assessment of nuclear morphology using Hoechst 33342/Propidium Iodide staining. Viable cell number was assessed by CellTiter-Glo luminescence assay, Caspase-8 and -9 activities were measured by Caspase-Glo™ assay kit. TRAIL-resistant cells were generated by culture of RPMI 8226 and NCI-H929 by acute exposure to TRAIL followed by selection of TRAIL-resistant cells. TRAIL significantly induced apoptosis in a dose-dependent manner in OPM-2, RPMI 8226, NCI-H929, U266, JJN-3 MM cell lines and ADC-1 plasma cell leukaemia cells. SAHA amplified TRAIL responses in all lines except OPM-2, and enhanced TRAIL responses were both via Caspase-8 and -9. SAHA treatment induced growth inhibition that further increased in the combination treatment with TRAIL in MM cells. The co-treatment of TRAIL and SAHA reduced viable cell numbers all cell lines. TRAIL responses were further potentiated by SAHA in 3D cell culture in NCI-H929, RPMI 8226 and U266 at lower TRAIL + SAHA doses than in suspension culture. However TRAIL responses in cells that had been selected for TRAIL resistance were not further enhanced by SAHA treatment. SAHA is a potent sensitizer of TRAIL responses in both TRAIL sensitive and resistant cell lines, in both suspension and 3D culture, however SAHA did not sensitise TRAIL-sensitive cell populations that had been selected for TRAIL-resistance from initially TRAIL-sensitive populations. SAHA may increase TRAIL sensitivity in insensitive cells, but not in cells that have specifically been selected for acquired TRAIL-resistance. [Abstract copyright: Copyright © 2017 Elsevier Inc. All rights reserved.

    Antibacterial Resistance Leadership Group 2.0: Back to Business

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    In December 2019, the Antibacterial Resistance Leadership Group (ARLG) was awarded funding for another 7-year cycle to support a clinical research network on antibacterial resistance. ARLG 2.0 has 3 overarching research priorities: infections caused by antibiotic-resistant (AR) gram-negative bacteria, infections caused by AR gram-positive bacteria, and diagnostic tests to optimize use of antibiotics. To support the next generation of AR researchers, the ARLG offers 3 mentoring opportunities: the ARLG Fellowship, Early Stage Investigator seed grants, and the Trialists in Training Program. The purpose of this article is to update the scientific community on the progress made in the original funding period and to encourage submission of clinical research that addresses 1 or more of the research priority areas of ARLG 2.0

    Global, regional, and national burden of neck pain in the general population, 1990-2017: Systematic analysis of the Global Burden of Disease Study 2017

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    Objective: To use data from the Global Burden of Disease Study between 1990 and 2017 to report the rates and trends of point prevalence, annual incidence, and years lived with disability for neck pain in the general population of 195 countries. Design: Systematic analysis. Data source: Global Burden of Diseases, Injuries, and Risk Factors Study 2017. Main outcome measures: Numbers and age standardised rates per 100 000 population of neck pain point prevalence, annual incidence, and years lived with disability were compared across regions and countries by age, sex, and sociodemographic index. Estimates were reported with uncertainty intervals. Results: Globally in 2017 the age standardised rates for point prevalence of neck pain per 100 000 population was 3551.1 (95 uncertainty interval 3139.5 to 3977.9), for incidence of neck pain per 100 000 population was 806.6 (713.7 to 912.5), and for years lived with disability from neck pain per 100 000 population was 352.0 (245.6 to 493.3). These estimates did not change significantly between 1990 and 2017. The global point prevalence of neck pain in 2017 was higher in females compared with males, although this was not significant at the 0.05 level. Prevalence increased with age up to 70-74 years and then decreased. Norway (6151.2 (95 uncertainty interval 5382.3 to 6959.8)), Finland (5750.3 (5058.4 to 6518.3)), and Denmark (5316 (4674 to 6030.1)) had the three highest age standardised point prevalence estimates in 2017. The largest increases in age standardised point prevalence estimates from 1990 to 2017 were in the United Kingdom (14.6 (10.6 to 18.8)), Sweden (10.4 (6.0 to 15.4)), and Kuwait (2.6 (2.0 to 3.2)). In general, positive associations, but with fluctuations, were found between age standardised years lived with disability for neck pain and sociodemographic index at the global level and for all Global Burden of Disease regions, suggesting the burden is higher at higher sociodemographic indices. Conclusions: Neck pain is a serious public health problem in the general population, with the highest burden in Norway, Finland, and Denmark. Increasing population awareness about risk factors and preventive strategies for neck pain is warranted to reduce the future burden of this condition. © 2020 Author(s)

    The PanCam Instrument for the ExoMars Rover

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    The scientific objectives of the ExoMars rover are designed to answer several key questions in the search for life on Mars. In particular, the unique subsurface drill will address some of these, such as the possible existence and stability of subsurface organics. PanCam will establish the surface geological and morphological context for the mission, working in collaboration with other context instruments. Here, we describe the PanCam scientific objectives in geology, atmospheric science, and 3-D vision. We discuss the design of PanCam, which includes a stereo pair of Wide Angle Cameras (WACs), each of which has an 11-position filter wheel and a High Resolution Camera (HRC) for high-resolution investigations of rock texture at a distance. The cameras and electronics are housed in an optical bench that provides the mechanical interface to the rover mast and a planetary protection barrier. The electronic interface is via the PanCam Interface Unit (PIU), and power conditioning is via a DC-DC converter. PanCam also includes a calibration target mounted on the rover deck for radiometric calibration, fiducial markers for geometric calibration, and a rover inspection mirror.publishersversionPeer reviewe

    Volume I. Introduction to DUNE

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    The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE\u27s physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology
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