On the integrability of Degasperis-Procesi equation: control of the Sobolev norms and Birkhoff resonances

We consider the dispersive Degasperis-Procesi equation $u_t-u_{x x t}-\mathtt{c} u_{xxx}+4 \mathtt{c} u_x-u u_{xxx}-3 u_x u_{xx}+4 u u_x=0$ with $\mathtt{c}\neq 0$. In \cite{Deg} the authors proved that this equation possesses infinitely many conserved quantities. We prove that, in a neighborhood of the origin, there are infinitely many of such constants of motion which control the Sobolev norms and which are analytic in a neighborhood of the origin of some $H^s$ Sobolev space, both on $\mathbb{R}$ and $\mathbb{T}$. By the analysis of these conserved quantities we deduce a result of global well-posedness for solutions with small initial data and we show that, on the circle, the formal Birkhoff normal form of the Degasperis-Procesi at any order is action-preserving

Merger of compact stars in the two-families scenario

We analyse the phenomenological implications of the two-families scenario on the merger of compact stars. That scenario is based on the coexistence of both hadronic stars and strange quark stars. After discussing the classification of the possible mergers, we turn to detailed numerical simulations of the merger of two hadronic stars, i.e., "first family" stars in which delta resonances and hyperons are present, and we show results for the threshold mass of such binaries, for the mass dynamically ejected and the mass of the disk surrounding the post-merger object. We compare these results with those obtained within the one-family scenario and we conclude that relevant signatures of the two-families scenario can be suggested, in particular: the possibility of a rapid collapse to a black hole for masses even smaller than the ones associated to GW170817; during the first milliseconds, oscillations of the postmerger remnant at frequencies higher than the ones obtained in the one-family scenario; a large value of the mass dynamically ejected and a small mass of the disk, for binaries of low total mass. Finally, based on a population synthesis analysis, we present estimates of the number of mergers for: two hadronic stars; hadronic star - strange quark star; two strange quark stars. We show that for unequal mass systems and intermediate values of the total mass, the merger of a hadronic star and a strange quark star is very likely (GW170817 has a possible interpretation into this category of mergers). On the other hand, mergers of two strange quark stars are strongly suppressed.Comment: 18 pages, 16 figure

Convective Excitation of Inertial Modes in Binary Neutron Star Mergers

We present the first very long-term simulations (extending up to ~140 ms after merger) of binary neutron star mergers with piecewise polytropic equations of state and in full general relativity. Our simulations reveal that at a time of 30-50 ms after merger, parts of the star become convectively unstable, which triggers the excitation of inertial modes. The excited inertial modes are sustained up to several tens of milliseconds and are potentially observable by the planned third-generation gravitational-wave detectors at frequencies of a few kilohertz. Since inertial modes depend on the rotation rate of the star and they are triggered by a convective instability in the postmerger remnant, their detection in gravitational waves will provide a unique opportunity to probe the rotational and thermal state of the merger remnant. In addition, our findings have implications for the long-term evolution and stability of binary neutron star remnantsComment: 6 pages, 4 figure

Influência da variação da vazão nas características geométricas, dinâmicas e deposicionais de correntes de densidade

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Novel recurrent chromosome anomalies in Shwachman Diamond syndrome

Clonal chromosome anomalies are frequently acquired in the bone marrow (BM) of patients with Shwachman-Diamond syndrome (SDS), and two are the most frequent: an isochromosome of the long arm of chromosome 7, i(7)(q10), and an interstitial deletion of the long arm of chromosome 20, del(20)(q). Patients with SDS have a risk of developing myelodysplasia (MDS) and/or acute myeloid leukaemia (AML), and the presence of chromosome changes was studied in relation with this risk. Starting in 1999 we have monitored the cytogenetic picture of a cohort of 92 Italian patients with SDS by all suitable cytogenetic and molecular methods. Clonal anomalies in BM were present in 41/92 patients. The i(7)(q10) was observed in 16 patients, and the del(20)(q) in 15, both these changes in four, but in independent clones. So, the most frequent clonal anomalies were found in 35 patients. Other, different, clonal anomalies were found in the BM of 13 patients, in eight cases in the absence of i(7)(q10) or del(20)(q), in five cases in association with one of these changes. In these less common clonal anomalies, the distribution of the chromosomes involved was markedly disparate, and some of them were novel and recurrent: - structural rearrangements of chromosome 7, mainly unbalanced (deletions, inversions or translocations), were present in five of our 13 patients, three of whom developed MDS/AML. - a further complex rearrangement of the more common del(20)(q), leading to duplicated and deleted portions, was identical in two patients, with almost identical a-CGH profiles, neither developed MDS/AML. - an unbalanced translocation t(3;6), with partial trisomy of the long arm of chromosome 3 and partial monosomy of the long arm of chromosome 6, was not identical but very similar in two patients, one of whom developed MDS/AML

Comparative genomic hybridization on microarray (a-CGH) in constitutional and acquired mosaicism may detect as low as 8% abnormal cells

<p>Abstract</p> <p>Background</p> <p>The results of cytogenetic investigations on unbalanced chromosome anomalies, both constitutional and acquired, were largely improved by comparative genomic hybridization on microarray (a-CGH), but in mosaicism the ability of a-CGH to reliably detect imbalances is not yet well established. This problem of sensitivity is even more relevant in acquired mosaicism in neoplastic diseases, where cells carrying acquired imbalances coexist with normal cells, in particular when the proportion of abnormal cells may be low.</p> <p>We constructed a synthetic mosaicism by mixing the DNA of three patients carrying altogether seven chromosome imbalances with normal sex-matched DNA. Dilutions were prepared mimicking 5%, 6%, 7%, 8%, 10% and 15% levels of mosaicism. Oligomer-based a-CGH (244 K whole-genome system) was applied on the patients' DNA and customized slides designed around the regions of imbalance were used for the synthetic mosaics.</p> <p>Results and conclusions</p> <p>The a-CGH on the synthetic mosaics proved to be able to detect as low as 8% abnormal cells in the tissue examined. Although in our experiment some regions of imbalances escaped to be revealed at this level, and were detected only at 10-15% level, it should be remarked that these ones were the smallest analyzed, and that the imbalances recurrent as clonal anomalies in cancer and leukaemia are similar in size to those revealed at 8% level.</p

Osteochondroma as a cause of scapular winging in an adolescent: a case report and review of the literature

INTRODUCTION: Winged scapula is defined as the prominence of the medial border of the scapula. The classic etiopathology of scapular winging are injuries to the spinal accessory or long thoracic nerves resulting respectively in trapezius and serratus anterior palsy. To the best of our knowledge, there are only few reports of scapular lesions being mistaken for winging of the scapula. We report a rare case of a large scapular osteochondroma arising from the medial border and causing a pseudowinging of the scapula. CASE PRESENTATION: A 17-year-old Caucasian boy came to us complaining about a winged left scapula. The patient had a complete painless range of motion, but a large hard bony swelling was palpable along the medial border of his left scapula. A grating sensation was felt when his arm was passively abducted and/or elevated causing discomfort. A lesion revealed on X-rays was diagnosed as an osteochondroma of the medial border of his scapula. After preoperative examinations, he underwent open surgery in order to remove the lesion. A histological examination confirmed the clinical diagnosis of osteochondroma. A clinical examination 3 months later showed a full and painless range of motion, the absence of the grating sensation during passive abduction and elevation and the complete disappearance of his left shoulder deformity. After 2 years of follow-up, there were no clinical or radiological signs of recurrence. CONCLUSIONS: Despite its rarity osteochondroma should be considered in the differential diagnosis for any adolescent presenting with a winging of the scapula

Formação de professores na modalidade a distância: perfil dos egressos, permanência e saberes em um curso de Educação Física

Esse estudo buscou identificar o perfil dos estudantes que permaneceram no curso de licenciatura em Educação Física, na modalidade a distância, e os saberes significativos desenvolvidos nessa formação, relacionando-os com os motivos de permanência até o final do curso. O perfil dos estudantes foi analisado pelos dados disponibilizados pela secretaria do curso e, para analisar a formação em Educação Física, foi elaborado um grupo focal. Os estudantes que permaneceram (42,9%) são na maioria mulheres (52,9%); solteiros (51,9%); a porcentagem de 85,7% cursou a educação básica integralmente em escola pública; 88,4% possuem idade média de 35 anos e moram a uma distância média de 34 km do polo. Ficou de significativo dessa formação o letramento digital, os saberes pedagógicos desenvolvidos ao longo do curso e os saberes das práticas corporais, ao compreenderem a importância da Educação Física no processo de escolarização. Os motivos da permanência elencados foram a qualidade proporcionada pela universidade pública e aqueles de mérito individual como a persistência, a disciplina e a autonomia

Early aphasia rehabilitation is associated with functional reactivation of the left inferior frontal gyrus a pilot study

Background and Purpose—Early poststroke aphasia rehabilitation effects and their functional MRI (fMRI) correlates were investigated in a pilot, controlled longitudinal study. Methods—Twelve patients with mild/moderate aphasia (8 Broca, 3 anomic, and 1 Wernicke) were randomly assigned to daily language rehabilitation for 2 weeks (starting 2.2 [mean] days poststroke) or no rehabilitation. The Aachen Aphasia Test and fMRI recorded during an auditory comprehension task were performed at 3 time intervals: mean 2.2 (T1), 16.2 (T2), and 190 (T3) days poststroke. Results—Groups did not differ in terms of age, education, aphasia severity, lesions volume, baseline fMRI activations, and in task performance during fMRI across examinations. Rehabilitated patients significantly improved in naming and written language tasks (P<0.05) compared with no rehabilitation group both at T2 and T3. Functional activity at T1 was reduced in language-related cortical areas (right and left inferior frontal gyrus and middle temporal gyrus, right inferior parietal lobule and superior temporal gyrus) in patients compared with controls. T2 and T3 follow-ups revealed a cortical activation increase, with significantly greater activation in the left hemisphere areas in rehabilitated patients at T2 and T3, and a time×treatment effect at T2 in the left inferior Broca area after rehabilitation. Left inferior frontal gyrus activation at T2 significantly correlated with naming improvement. Conclusions—Early poststroke aphasia treatment is useful, has durable effects, and may lead to early enhanced recruitment of brain areas, particularly the left inferior frontal gyrus, which persists in the chronic phase