444 research outputs found

    Persistent memory in athermal systems in deformable energy landscapes

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    We show that memory can be encoded in a model amorphous solid subjected to athermal oscillatory shear deformations, and in an analogous spin model with disordered interactions, sharing the feature of a deformable energy landscape. When these systems are subjected to oscillatory shear deformation, they retain memory of the deformation amplitude imposed in the training phase, when the amplitude is below a "localization" threshold. Remarkably, multiple, persistent, memories can be stored using such an athermal, noise-free, protocol. The possibility of such memory is shown to be linked to the presence of plastic deformations and associated limit cycles traversed by the system, which exhibit avalanche statistics also seen in related contexts.Comment: 5 pages, 4 figure

    Geophysical Research

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    Contains reports on two research projects.Joint Services Electronics Programs (U. S. Army, U. S. Navy, and U. S. Air Force) under Contract DA 28-043-AMC-02536(E)National Aeronautics and Space Administration (Grant NGR-22-009-131)National Aeronautics and Space Administration (Grant NGR-22-009-114)National Aeronautics and Space Administration (Contract NAS 12-436

    Differences in pharmacology of tumor necrosis factor (TNF) antagonists

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    The commercially available inhibitors of TNF are constituted by two classes of molecules: the soluble receptors (Etanercept: Amgen Inc. Wyeth) and the monoclonal antibodies (Adalimumab: Abbott Laboratories and Infliximab: Centocor, Inc.). The differences in their molecular structure, mechanism of action, pharmacokinetics (PK) and pharmacodynamics (PD) are discussed, along with the differences concerning dose, administration regimens, drug concentrations and pharmacological interactions. In order to explain the clinical differences observed when these agents are used in the "real world", which can arise from the respective PK characteristics (kinetics, route and frequency of administration, type of TNF binding, effects on cytokines) and PD responses and peculiar mechanisms of action, with distinctive immune function (LFTa inactivation; apoptosis induction, TNF immunoprecipitation, C1q binding and CDC induction; Fcg cross-linking and ADCC induction), the dynamics of interaction of the two classes of neutralizing molecules with TNF, and the ability in restoring TNF homeostasis, are outlined

    Angiogenic gene expression and vascular density are reflected in ultrasonographic features of synovitis in early Rheumatoid Arthritis: an observational study.

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    INTRODUCTION: Neovascularization contributes to the development of sustained synovial inflammation in the early stages of Rheumatoid Arthritis. Ultrasound (US) provides an indirect method of assessing synovial blood flow and has been shown to correlate with clinical disease activity in patients with Rheumatoid Arthritis. This study examines the relationship of US determined synovitis with synovial vascularity, angiogenic/lymphangiogenic factors and cellular mediators of inflammation in a cohort of patients with early Rheumatoid Arthritis (RA) patients prior to therapeutic intervention with disease modifying therapy or corticosteroids. METHODS: An ultrasound guided synovial biopsy of the supra-patella pouch was performed in 12 patients with early RA prior to treatment. Clinical, US and biochemical assessments were undertaken prior to the procedure. Ultrasound images and histological samples were obtained from the supra-patella pouch. Histological samples were stained for Factor VIII and a-SMA (a-smooth muscle actin). Using digital imaging analysis a vascular area score was recorded. QT-PCR (quantitative-PCR) of samples provided quantification of angiogenic and lymphangiogenic gene expression and immunohistochemistry stained tissue was scored for macrophage, T cell and B cell infiltration using an existing semi-quantitative score. RESULTS: Power Doppler showed a good correlation with histological vascular area (Spearman r--0.73) and angiogenic factors such as vascular endothelial growth factor-A (VEGF-A), Angiopoietin 2 and Tie-2. In addition, lymphangiogenic factors such as VEGF-C and VEGF-R3 correlated well with US assessment of synovitis. A significant correlation was also found between power Doppler and synovial thickness, pro-inflammatory cytokines and sub-lining macrophage infiltrate. Within the supra-patella pouch there was no significant difference in US findings, gene expression or inflammatory cell infiltrate between any regions of synovium biopsied. CONCLUSION: Ultrasound assessment of synovial tissue faithfully reflects synovial vascularity. Both grey scale and power Doppler synovitis in early RA patients correlate with a pro-angiogenic and lymphangiogenic gene expression profile. In early RA both grey scale and power Doppler synovitis are associated with a pro-inflammatory cellular and cytokine profile providing considerable validity in its use as an objective assessment of synovial inflammation in clinical practice

    Radio Astronomy

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    Contains reports on four research projects.National Science Foundation (Grant G-13904)National Aeronautics and Space Administration (Contract NaSr-101)National Aeronautics and Space Administration (Grant NsG-250-62

    The impact of alkaline treatments on elasticity in spruce tonewood

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    It is commonly believed that violins sound differently when finished. However, if the role of varnishes on the vibrational properties of these musical instruments is well-established, how the first components of the complete wood finish impact on the final result is still unclear. According to tradition, the priming process consists of two distinct stages, called pre-treatment and sizing. The literature reports some recipes used by old Cremonese luthiers as primers, mainly based on alkaline aqueous solutions and protein-based glues. In this manuscript, we analyze the impact of these treatments on the mechanical properties of the material. The combination of two pre-treatments and three sizes is considered on nine different plates. We compare the vibrational properties before and after the application and assess the effects of the different primers, also supported by finite element modeling. The main outcome is that the combination of particular treatments on the violin surface before varnishing leads to changes not only to the wood appearance, but also to its vibrational properties. Indeed pre-treatments, often considered negligible in terms of vibrational changes, enhance the penetration of the size into the wood structure and strengthen the impact of the latter on the final rigidity of the material along the longitudinal and radial directions

    IL-1Ra (recombinant human IL-1 receptor antagonist) in the treatment of rheumatoid arthritis: the efficacy

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    Interleukin 1 receptor antagonist (IL-1Ra) is a naturally occurring IL-1 inhibitor, acting as a "receptor antagonist", which blocks IL-1 mediated signal transduction. In 1990 IL-1Ra was cloned and later on, a large numbers of studies led to disclosure of the crucial importance of the imbalance between IL-1 and IL-1Ra in the pathogenesis of rheumatoid arthritis (RA). In 1991, almost 8 years after the initial isolation of IL-1, recombinant IL-1Ra (IL-1ra, Kineret) was introduced in clinical trials involving patients with RA. Between 2001 and 2002 IL-1ra was approved by the US Food and Drug Administration and by the European Agency for the Evaluation of the Medicinal Products and in 2003 it was registered in Italy, too. In RA recombinant IL-1ra has been evaluated in 5 randomized, placebo-controlled clinical trials involving more than 2900 patients. Two of the trials involved the use of IL-1ra as monotherapy versus placebo and two trials in combination with methotrexate (MTX); the last trial explored the use of a fixed 100 mg/day IL-1ra dosage in a RA patient population including a wide array of co-morbid conditions as well as concomitant medications. The studies confirmed both the efficacy and the safety of IL-1ra in patients with active and severe RA. 43% of patients receiving 150 mg/day IL-1ra achieved a 20% response according to the American College of Rheumatology criteria (ACR20), compared to 27% in the placebo group. In the MTX combination therapy study, 42% of the patients receiving 1 mg/Kg/day of IL-1ra achieved an ACR20, 24% an ACR50 and 10% an ACR70. In each study, significant improvements in the Health Assessment Questionnaire scores (HAQ) were observed. There were rapid gains in the number of days at work or domestic activity in the treated patients, and the increases in productivity were dose related. At early 24 weeks, there was significant reduction of both the score for progression of joint space narrowing (JSN) and the Total modified Sharp-Genant score (a combination of erosion and JSN) in all treatment groups (30,75 and 150mg/day). The clinical benefits of treatment with daily subcutaneous injections of IL-1ra in active RA patients were maintained for up to 48 weeks. IL-1ra, a selective inhibitor of the IL-1 pathway, represents an important new biologic approach to treating patients with RA, that significantly reduces clinical signs and symptoms of the disease and joint destruction and has proved safe and well tolerated also in combination with other DMARDs and concomitant medications

    A multicenter, prospective cohort study

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    Organ transplant recipients (OTRs) have a 100ā€fold increased risk of cutaneous squamous cell carcinoma (cSCC). We prospectively evaluated the association between Ī² genus human papillomaviruses (Ī²PV) and keratinocyte carcinoma in OTRs. Two OTR cohorts without cSCC were assembled: cohort 1 was transplanted in 2003ā€2006 (n = 274) and cohort 2 was transplanted in 1986ā€2002 (n = 352). Participants were followed until death or cessation of followā€up in 2016. Ī²PV infection was assessed in eyebrow hair by using polymerase chain reactionā€“based methods. Ī²PV IgG seroresponses were determined with multiplex serology. A competing risk model with delayed entry was used to estimate cumulative incidence of histologically proven cSCC and the effect of Ī²PV by using a multivariable Cox regression model. Results are reported as adjusted hazard ratios (HRs). OTRs with 5 or more different Ī²PV types in eyebrow hair had 1.7 times the risk of cSCC vs OTRs with 0 to 4 different types (HR 1.7, 95% confidence interval 1.1ā€2.6). A similar risk was seen with high Ī²PV loads (HR 1.8, 95% confidence interval 1.2ā€2.8). No significant associations were seen between serum antibodies and cSCC or between Ī²PV and basal cell carcinoma. The diversity and load of Ī²PV types in eyebrow hair are associated with cSCC risk in OTRs, providing evidence that Ī²PV is associated with cSCC carcinogenesis and may present a target for future preventive strategies
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