On the definition of temperature in FPU systems

It is usually assumed, in classical statistical mechanics, that the temperature should coincide, apart from a suitable constant factor, with the mean kinetic energy of the particles. We show that this is not the case for \FPU systems, in conditions in which energy equipartition between the modes is not attained. We find that the temperature should be rather identified with the mean value of the energy of the low frequency modes.Comment: 12 pages, 4 Figure

From anomalous energy diffusion to Levy walks and heat conductivity in one-dimensional systems

The evolution of infinitesimal, localized perturbations is investigated in a one-dimensional diatomic gas of hard-point particles (HPG) and thereby connected to energy diffusion. As a result, a Levy walk description, which was so far invoked to explain anomalous heat conductivity in the context of non-interacting particles is here shown to extend to the general case of truly many-body systems. Our approach does not only provide a firm evidence that energy diffusion is anomalous in the HPG, but proves definitely superior to direct methods for estimating the divergence rate of heat conductivity which turns out to be $0.333\pm 0.004$, in perfect agreement with the dynamical renormalization--group prediction (1/3).Comment: 4 pages, 3 figure

No more time to stay ‘single’ in the detection of Anisakis pegreffii, A. simplex (s. s.) and hybridization events between them: a multi-marker nuclear genotyping approach

A multi-marker nuclear genotyping approach was performed on larval and adult specimens of Anisakis spp. (N = 689) collected from fish and cetaceans in allopatric and sympatric areas of the two species Anisakis pegreffii and Anisakis simplex (s. s.), in order to: (1) identify specimens belonging to the parental taxa by using nuclear markers (allozymes loci) and sequence analysis of a new diagnostic nuclear DNA locus (i.e. partial sequence of the EF1 α−1 nDNA region) and (2) recognize hybrid categories. According to the Bayesian clustering algorithms, based on those markers, most of the individuals (N = 678) were identified as the parental species [i.e. A. pegreffii or A. simplex (s. s.)], whereas a smaller portion (N = 11) were recognized as F1 hybrids. Discordant results were obtained when using the polymerase chain reaction–restriction fragment length polymorphisms (PCR–RFLPs) of the internal transcribed spacer (ITS) ribosomal DNA (rDNA) on the same specimens, which indicated the occurrence of a large number of ‘hybrids’ both in sympatry and allopatry. These findings raise the question of possible misidentification of specimens belonging to the two parental Anisakis and their hybrid categories derived from the application of that single marker (i.e. PCR–RFLPs analysis of the ITS of rDNA). Finally, Bayesian clustering, using allozymes and EF1 α−1 nDNA markers, has demonstrated that hybridization between A. pegreffii and A. simplex (s. s.) is a contemporary phenomenon in sympatric areas, while no introgressive hybridization takes place between the two species

Blocking CD248 molecules in perivascular stromal cells of patients with systemic sclerosis strongly inhibits their differentiation toward myofibroblasts and proliferation: A new potential target for antifibrotic therapy

Background: Fibrosis may be considered the hallmark of systemic sclerosis (SSc), the end stage triggered by different pathological events. Transforming growth factor-β (TGF-β) and platelet-derived growth factor BB (PDGF-BB) are profibrotic molecules modulating myofibroblast differentiation and proliferation, respectively. There is evidence linking CD248 with these two molecules, both highly expressed in patients with SSc, and suggesting that CD248 may be a therapeutic target for several diseases. The aim of this work was to evaluate the expression of CD248 in SSc skin and its ability to modulate SSc fibrotic process. Methods: After ethical approval was obtained, skin biopsies were collected from 20 patients with SSc and 10 healthy control subjects (HC). CD248 expression was investigated in the skin, as well as in bone marrow mesenchymal stem cells (MSCs) treated with TGF-β or PDGF-BB, by immunofluorescence, qRT-PCR, and Western blotting. Finally, in SSc-MSCs, the CD248 gene was silenced by siRNA. Results: Increased expression of CD248 was found in endothelial cells and perivascular stromal cells of SSc skin. In SSc-MSCs, the levels of CD248 and α-smooth muscle actin expression were significantly higher than in HC-MSCs. In both SSc- and HC-MSCs, PDGF-BB induced increased expression of Ki-67 when compared with untreated cells but was unable to modulate CD248 levels. After CD248 silencing, both TGF-β and PDGF-BB signaling were inhibited in SSc-MSCs. Conclusions: CD248 overexpression may play an important role in the fibrotic process by modulating the molecular target, leading to perivascular cells differentiation toward myofibroblasts and interfering with its expression, and thus might open a new therapeutic strategy to inhibit myofibroblast generation during SSc

Phase space structures and ionization dynamics of hydrogen atom in elliptically polarized microwaves

The multiphoton ionization of hydrogen atoms in a strong elliptically polarized microwave field exhibits complex features that are not observed for ionization in circular and linear polarized fields. Experimental data reveal high sensitivity of ionization dynamics to the small changes of the field polarization. The multidimensional nature of the problem makes widely used diagnostics of dynamics, such as Poincar\'{e} surfaces of section, impractical. We analyze the phase space dynamics using finite time stability analysis rendered by the fast Lyapunov Indicators technique. The concept of zero--velocity surface is used to initialize the calculations and visualize the dynamics. Our analysis provides stability maps calculated for the initial energy at the maximum and below the saddle of the zero-velocity surface. We estimate qualitatively the dependence of ionization thresholds on the parameters of the applied field, such as polarization and scaled amplitude

Managing Adult-onset Still's disease: The effectiveness of high-dosage of corticosteroids as first-line treatment in inducing the clinical remission. Results from an observational study

To assess the effectiveness of the treatment with high dosage of corticosteroids (CCSs), as first-line therapy, in inducing remission in naïve Adult-onset Still's disease (AOSD) patients compared with low dosage of CCSs, after 6 months. To further evaluate the rate of patients maintaining the remission and the rate of CCSs discontinuation, after additional 12 months of follow-up.A retrospective evaluation of patients prospectively followed was designed to compare the rate of clinical remission in naïve AOSD patients treated with high dosages of CCSs (0.8-1 mg/kg/day of prednisone-equivalent) or low dosage of CCSs (0.2-0.3 mg/kg/day of prednisone-equivalent), after 6 months. An additional analysis was performed to compare the rate of monocyclic pattern between these groups, after further 12 months of follow-up.The clinical remission was achieved in a higher percentage of patients treated with the first-line treatment with high dosage of CCSs than treated the first-line treatment with low dosage of CCSs. At the end of 18 months of follow-up, a larger percentage of patients treated the first-line treatment with high dosage of CCSs was classified as monocyclic pattern and discontinued CCSs when compared with patients treated the first-line treatment with low dosage of CCSs. Patients defined as CCSs non-responder were treated with methotrexate (MTX)+CCSs or with combination therapy CCSs+MTX+biologic drug. The clinical remission was observed in a percentage of these patients.We showed the effectiveness of the first-line treatment with high dosage of CCSs in inducing clinical remission in naïve AOSD patients when compared with the first-line treatment with low dosage of CCSs. The first-line treatment with high dosage of CCSs was also associated with the achievement of monocyclic pattern and CCSs discontinuation, after 18 months of follow-up

Dermatological high-dose-rate brachytherapy for the treatment of basal and squamous cell carcinoma

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are among the most common cancers in humans. Various therapies are currently being used to treat these tumours including surgery, topical treatments and radiotherapy. We describe a new treatment for BCC and SCC. This consists of superficial radiotherapy, using synthetic resin containing a radioactive beta-emitting isotope. The resin is applied to the lesion to perform a selective beta-irradiation brachytherapy treatment

Biodisponibilidade de Arsênio em Dois Solos de Granulometrias Distintas sob Adição de Fosfato e Arsenato.

? Nos coloides do solo, o fosfato e o arsenato competem por sítios de adsorção, sendo que a adição de fosfato por meio de fertilizantes, por exemplo, pode elevar os teores de As em solução, tornando-o mais disponível para as plantas. Por outro lado, por competirem por sítios de absorção nas raízes, maiores teores de As em solução podem inibir a absorção de P e vice-versa. Dessa forma, este experimento teve como objetivo avaliar a biodisponibilidade de arsênio ao longo de 2 meses após a aplicação de doses de fosfato e arsenato em dois solos de granulometrias distintas. O experimento foi conduzido em casa de vegetação do Departamento de Solos da Universidade Federal de Viçosa utilizando-se um solo arenoso e um muito argiloso. O solos receberam cinco doses de P (0, 44, 150, 256, e 300 mg.kg -1 ) na forma de fosfato de sódio e cinco doses de As (0, 22, 75, 128 e 150 mg.kg -1 ) na forma de arsenato de sódio. A biodisponibilidade de arsênio foi analisada aos 15, 30 e 60 dias após a aplicação dos tratamentos, através do método de Neubauer e Schneider (1923). O delineamento utilizado foi o delineamento Central Composto Rotacional (DCCR), com cinco repetições no ponto central e valor alfa igual a 1,41. Os dados foram analisados por meio de superfície de respostas e demonstraram que a alta concentração de fósforo em solução compensa a maior disponibilidade de arsenato, causada por sua adição, podendo, assim, amenizar os efeitos fitotóxicos do arsênio

Mesenchymal stromal cells and rheumatic diseases: new tools from pathogenesis to regenerative therapies

In recent years, mesenchymal stromal cells (MSCs) have been largely investigated and tested as a new therapeutic tool for several clinical applications, including the treatment of different rheumatic diseases. MSCs are responsible for the normal turnover and maintenance of adult mesenchymal tissues as the result of their multipotent differentiation abilities and their secretion of a variety of cytokines and growth factors. Although initially derived from bone marrow, MSCs are present in many different tissues such as many peri-articular tissues. MSCs may exert immune-modulatory properties, modulating different immune cells in both in vitro and in vivo models, and they are considered immune-privileged cells. At present, these capacities are considered the most intriguing aspect of their biology, introducing the possibility that these cells may be used as effective therapy in autoimmune diseases. Therefore, stem cell therapies may represent an innovative approach for the treatment of rheumatic diseases, especially for the forms that are not responsive to standard treatments or alternatively still lacking a definite therapy. At present, although the data from scientific literature appear to suggest that such treatments might be more effective whether administered as soon as possible, the use of MSCs in clinical practice is likely to be restricted to patients with a long history of a severe refractory disease. Further results from larger clinical trials are needed to corroborate preclinical findings and human non-controlled studies, and advancement in the knowledge of MSCs might provide information about the therapeutic role of these cells in the treatment of many rheumatic diseases