371 research outputs found

    Steady state fluctuation relations for systems driven by an external random force

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    We experimentally study the fluctuations of the work done by an external Gaussian random force on two different stochastic systems coupled to a thermal bath: a colloidal particle in an optical trap and an atomic force microscopy cantilever. We determine the corresponding probability density functions for different random forcing amplitudes ranging from a small fraction to several times the amplitude of the thermal noise. In both systems for sufficiently weak forcing amplitudes the work fluctuations satisfy the usual steady state fluctuation theorem. As the forcing amplitude drives the system far from equilibrium, deviations of the fluctuation theorem increase monotonically. The deviations can be recasted to a single master curve which only depends on the kind of stochastic external force.Comment: 6 pages, submitted to EP

    Intersections of self-gravitating charged shells in a Reissner-Nordstrom field

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    We describe the equation of motion of two charged spherical shells with tangential pressure in the field of a central Reissner-Nordstrom (RN) source. We solve the problem of determining the motion of the two shells \textsl{after} the intersection by solving the related Einstein-Maxwell equations and by requiring a physical continuity condition on the shells velocities. We consider also four applications: post-Newtonian and ultra-relativistic approximations, a test-shell case, and the ejection mechanism of one shell. This work is a direct generalization of Barkov-Belinski-Bisnovati-Kogan paper.Comment: 21 pages, 1 figure;v3 added reference

    Subclinical dermal involvement is detectable by high frequency ultrasound even in patients with limited cutaneous systemic sclerosis.

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    Background: The aim of the study was to detect by skin high-frequency ultrasound (US) possible subclinical skin involvement in patients affected by limited cutaneous systemic sclerosis (lcSSc), in those skin areas apparently not affected by the disease on the basis of a normal modified Rodnan skin score (mRSS). Differences in dermal thickness (DT) in comparison with healthy subjects were investigated. Methods: Fifty patients with lcSSc (age 62 \ub1 13 years (mean \ub1 SD), disease duration 5 \ub1 5 years) and 50 sex-matched and age-matched healthy subjects (age 62 \ub1 11 years) were enrolled. DT was evaluated by both mRSS and US at the usual 17 skin areas (zygoma, fingers, dorsum of the hands, forearms, upper arms, chest, abdomen, thighs, lower legs and feet). Non-parametric tests were used for the statistical analysis. Results: Subclinical dermal involvement was detected by US even in the skin areas in patients with lcSSc, who had a normal local mRSS. In addition, statistically significantly higher mean DT was found in almost all skin areas, when compared to healthy subjects (p < 0.0001 for all areas). In particular, DT was significantly greater in patients with lcSSc than in healthy subjects in four out of six skin areas with a normal mRSS (score = 0) (upper arm, chest and abdomen), despite the clinical classification of lcSSc. Conclusions: This study strongly suggests that subclinical dermal involvement may be detectable by US even in skin areas with a normal mRSS in patients classified as having lcSSc. This should be taken into account during SSc subset classification in clinical studies/trial

    Understanding the process of recovery from heroin addiction : initiating and maintaining factors

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    There is increasing recognition that recovery from heroin addiction is possible but there is limited understanding of the recovery process and of how services can support people in that process. At present, most of the research concerning recovery from heroin addiction comes from the United States where the treatment system is very different to that in the UK. This study aimed to gain a better understanding of the recovery process from the perspective of people who are in recovery from heroin addiction, with the aim of informing service development and delivery in the South Wales area. This study employed a grounded theory qualitative methodology to analyse data collected from ten interviews with people in recovery from heroin addiction in the South Wales area. The results revealed four core categories: i) initiating recovery, including the triggers for recovery and what helps; ii) maintaining recovery, consisting of thought changes, lifestyle changes and the role of supportive networks; iii) the reality of recovery, encompassing the process of recovery and obstacles faced; and iv) service provision, encompassing current problems, how support needs can be met and how wider needs can be addressed. The findings highlighted some important considerations for the development of services specifically designed to meet the needs of this client group, thus facilitating long term stable recovery. The findings are reviewed in relation to the wider literature regarding recovery from heroin addiction. Implications for clinical practice and service delivery are also reviewed, and suggestions provided for how services can incorporate recovery-orientated principles. Suggestions for future research are also considered.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Primary cutaneous alk positive anaplastic large cell lymphoma in a melanoma patient

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    Primary cutaneous anaplastic large cell lymphoma (PCALCL) is a raresubset of CD30+ lymphoproliferative disorder, characterized by the presenceof large anaplastic cells, which express CD30, CD2, CD3, CD4, and CD5. A 62 year-old male patient presented to our Institute with a history of a fastgrowing and pinkish-brown asymptomatic cutaneous nodule. His medical past history was positive for a malignant melanoma (MM) of the abdomen (0.7 mm Breslow thickness; pT1a). Histologically the lesion showed a diffuse infiltrate consisting in cohesive sheets of large cells with anaplastic morphology with a kidney-shaped nucleus, also known as hallmark cells. Immunohistochemical studies revealed a CD30 expression, and a positivity to perforin and anaplastic lymphoma kinase (ALK). The laboratory and instrumental investigations were all normal and a final diagnosis of PCALCL was made. The patient showed a good response to radiotherapy. Usually PCALCL shares with systemic anaplastic large cell lymphoma (ALCL) the presence of neoplastic CD30+ large T cells, but lack ALK translocations and protein expression. However, the detection of ALK expression in PCALCL should be considered highly suspicious of a cutaneous manifestation of an underlying systemic disease (not detected in our patient). We recommend to exclude a systemic involvement in this kind of disease, with a strict follow-up, especially in patients with double malignancies

    SAT0484 TRABECULAR BONE SCORE IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS

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    Background:Systemic lupus erythematosus (SLE) patients shown an increased risk of low bone mass as a result of multifactorial events: physical inactivity, persistent inflammation, low vitamin D levels (photosensitivity) and glucocorticoid treatment. Trabecular Bone Score (TBS), is an index extracted from the dual-energy X-ray absorptiometry (DXA) that provides an indirect measurement of bone axial microarchitecture and allows to get information about bone quality in several rheumatic diseases (1-4).Objectives:The aims of this study were to examine the prevalence and risk factors for low bone mineral density (BMD) (osteoporosis or osteopenia) in female patients affected by SLE and to compare with matched healthy subjects (CNT).Methods:70 female patients (mean age 41±20 years) affected by SLE and 65 age- matched CNT (mean age 46±7 years) were enrolled. Bone Mineral Density (BMD, g/cm2) of the lumbar spine (L1-L4) was analyzed using a DXA scan (GE, Lunar Prodigy). Lumbar spine TBS was derived for each spine DXA examination using the TBS index (TBS iNsight Medimaps).Results:The mean BMD±SD was 0.47±0.57 g/cm2 at the lumbar spine and 0.78 ± 0.22 g/cm2 at the hip in SLE patients. The prevalence of osteopenia was 40.0% and was 19.4% of osteoporosis in SLE patients. Most of SLE patients (75%) presented a bone loss that was significantly higher when compared with control group (p<0.001). Lumbar spine TBS score was found significantly lower in SLE patients compared with CNT (0.687±0.675 vs, 1.294±0.809 p<0.001, respectively) and of 0,47±0,94 times lower than expected from the concomitant reference BMD value.Conclusion:The study shows that the further TBS analysis, independently from the concomitant BMD value, is significatively lower then expected in SLE patients. The detection of the TBS, together with the BMD, may offer a more reliable indication of the real whole bone condition in chronic and systemic inflammatory rheumatic diseases, such as SLE.References:[1]Cutolo M et al. Ann Rheum Dis. 2009;68 446-7; 2 Dey M et al. Lupus. 018;271547-1551; 3 Ruaro B, Casabella A, et al. Rheumatology (Oxford). 2018;57:1548-1554. 4 Ruaro B, Casabella A, et al. Clin Rheumatol. 2018 Nov;37(11):3057-3062.Disclosure of Interests:Andrea Casabella: None declared, Sabrina Paolino: None declared, Elisa Alessandri: None declared, Vanessa Smith Grant/research support from: The affiliated company received grants from Research Foundation - Flanders (FWO), Belgian Fund for Scientific Research in Rheumatic diseases (FWRO), Boehringer Ingelheim Pharma GmbH & Co and Janssen-Cilag NV, Consultant of: Boehringer-Ingelheim Pharma GmbH & Co, Speakers bureau: Actelion Pharmaceuticals Ltd, Boehringer-Ingelheim Pharma GmbH & Co and UCB Biopharma Sprl, Barbara Ruaro: None declared, Carmen Pizzorni: None declared, Alberto Sulli Grant/research support from: Laboratori Baldacci, Maurizio Cutolo Grant/research support from: Bristol-Myers Squibb, Actelion, Celgene, Consultant of: Bristol-Myers Squibb, Speakers bureau: Sigma-Alph

    Entropy production and fluctuation theorems under feedback control: the molecular refrigerator model revisited

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    We revisit the model of a Brownian particle in a heat bath submitted to an actively controlled force proportional to the velocity that leads to thermal noise reduction (cold damping). We investigate the influence of the continuous feedback on the fluctuations of the total entropy production and show that the explicit expression of the detailed fluctuation theorem involves different dynamics and observables in the forward and backward processes. As an illustration, we study the analytically solvable case of a harmonic oscillator and calculate the characteristic function of the entropy production in a nonequilibrium steady state. We then determine the corresponding large deviation function which results from an unusual interplay between 'boundary' and 'bulk' contributions.Comment: 16 pages, 5 figures. References 9,10,13,14,15 added. A few changes in the text. Accepted for publication in J. Stat. Mec

    Ictal epileptic headache: When terminology is not a moot question

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    open7noThe relationship between headache and epilepsy is complex and despite the nature of this association is not yet clear. In the last few years, it has been progressively introduced the concept of the “ictal epileptic headache” that was included in the recently revised International Classification of Headaches Disorders 3rd edition (ICHD-3-revised). The diagnostic criteria for ictal epileptic headache (IEH) suggested in 2012 were quite restrictive thus leading to the underestimation of this phenomenon. However, these criteria have not yet been included into the ICHD-3 revision published in 2018, thus creating confusion among both, physicians and experts in this field. Here, we highlight the importance to strictly apply the original IEH criteria explaining the reasons through the analysis of the clinical, historical, epidemiological and pathophysiological characteristics of the IEH itself. In addition, we discuss the issues related to the neurophysiopathological link between headache and epilepsy as well as to the classification of these epileptic events as “autonomic seizure”.openParisi P.; Paolino M.C.; Raucci U.; Vecchia N.D.; Belcastro V.; Villa M.P.; Striano P.Parisi, P.; Paolino, M. C.; Raucci, U.; Vecchia, N. D.; Belcastro, V.; Villa, M. P.; Striano, P

    INTERACTION BETWEEN NANOFILLED COMPOSITES AND POLYWAVE MULTILED CURING LAMPS: AN IN VITRO STUDY

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    8nonenoneBattaglia V; Bergantin E; Paolino D; Coero Borga FA; Cadenaro M; Breschi L; Berutti E; Scotti N.Battaglia, V; Bergantin, E; Paolino, D; Coero Borga, Fa; Cadenaro, Milena; Breschi, Lorenzo; Berutti, E; Scotti, Nicol
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