Model Order Selection Rules For Covariance Structure Classification

The adaptive classification of the interference covariance matrix structure for radar signal processing applications is addressed in this paper. This represents a key issue because many detection architectures are synthesized assuming a specific covariance structure which may not necessarily coincide with the actual one due to the joint action of the system and environment uncertainties. The considered classification problem is cast in terms of a multiple hypotheses test with some nested alternatives and the theory of Model Order Selection (MOS) is exploited to devise suitable decision rules. Several MOS techniques, such as the Akaike, Takeuchi, and Bayesian information criteria are adopted and the corresponding merits and drawbacks are discussed. At the analysis stage, illustrating examples for the probability of correct model selection are presented showing the effectiveness of the proposed rules

Finite driving rate and anisotropy effects in landslide modeling

In order to characterize landslide frequency-size distributions and individuate hazard scenarios and their possible precursors, we investigate a cellular automaton where the effects of a finite driving rate and the anisotropy are taken into account. The model is able to reproduce observed features of landslide events, such as power-law distributions, as experimentally reported. We analyze the key role of the driving rate and show that, as it is increased, a crossover from power-law to non power-law behaviors occurs. Finally, a systematic investigation of the model on varying its anisotropy factors is performed and the full diagram of its dynamical behaviors is presented.Comment: 8 pages, 9 figure

Linfoma Não Hodgkin de Células T Citotóxico: uma Apresentação Clínica Atípica

Cytotoxic lymphomas comprise a spectrum of peripheral T-cell lymphomas that can have a initial or late cutaneous presentation. We describe a 46-year-old man from Cape Verde, with a dermatosis involving his face and trunk, consisting of monomorphic papules with a smooth surface and both motor and sensory polyneuropathy.The hypothesis of leprosy was supported by the clinical and initial hystopathological findings and the patient was referred to our hospital with suspected Hansen's disease. In the new skin and lymph node biopsies a lymphocyte population was identified whose immunohystochemistry study allowed the diagnosis of T-cell lymphoma with expression of cytotoxic markers. The patient was started on chemotherapy with initial remission of the skin lesions but, subsequently, progression of systemic disease.info:eu-repo/semantics/publishedVersio

Recurrent Nevus. A 5-Year Review

A persistência de uma lesão melanocítica, em local onde tenha sido previamente excisado um nevo melanocítico pode colocar, clínica e histologicamente, problemas no diagnóstico diferencial com melanoma, designado por alguns autores como ‘pseudomelanoma’. Neste estudo, os autores pretendem realizar uma análise comparativa entre os achados clínicos e histopatológicos das lesões melanocíticas primárias e dos nevos recorrentes. Procura-se também avaliar eventuais factores predisponentes para este fenómeno

Determination of a pre-heating sequence for the DONES Target Assembly

Within the activities promoted by the EUROfusion consortium in support of the design and construction of the DEMO Oriented NEutron Source (DONES), a mock-up of its Target Assembly (TA), based on the configuration with a “bayonet” Back-Plate (BP) and available at ENEA Brasimone labs, is being adopted for the execution of experimental activities aiming at the validation of specific aspects of the target design. Despite the “integral”-TA concept is the current reference, experimental tests concerning the TA pre-heating phase are not significantly affected by the TA concept and are still representative even though conducted on the bayonet-TA concept. Indeed, the main objective of the pre-heating phase is to raise the TA temperature up to a value close to that of the lithium flow in nominal condition (250 ◦C). In particular, one of the main concerns is to keep the BP at a temperature higher than 200 ◦C to avoid possible local lithium freezing. In order to support the afore-mentioned tests, a numerical research campaign has been launched by ENEA Brasimone in collaboration with the University of Palermo with the goal of determining an optimal design of the electrical heaters, both in terms of temperature set-points and geometrical layout. To this purpose, several configurations have been assessed following a theoretical-computational approach based on the Finite Element Method (FEM) and adopting the Abaqus FEM code. In a first phase, different electric heater layouts were assessed by means of steady state thermal analyses. Once the most promising scenario was selected, a detailed thermal transient analysis was carried out. An iterative procedure, based on the analysis of the maximum temperature achieved within the mock-up most critical components, was followed in order to determine the duty cycle of the electric heaters. The obtained numerical results are herewith reported and critically discussed

Optical coherence tomography angiography findings in Huntington’s disease

Objectives: To evaluate the retinal and choriocapillaris vascular networks in macular region and the central choroidal thickness (CCT) in patients affected by Huntington disease (HD), using optical coherence tomography angiography (OCTA) and enhanced depth imaging spectral-domain OCT (EDI SD-OCT). Methods: We assessed the vessel density (VD) in superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) using OCTA, while CCT was measured by EDI SD-OCT. Results: Sixteen HD patients (32 eyes) and thirteen healthy controls (26 eyes) were enrolled in this prospective study. No significant difference in retinal and choriocapillaris VD was found between HD patients and controls while CCT turned to be thinner in patients respect to controls. There were no significant relationships between OCTA findings and neurological parameters. Conclusion: The changes in choroidal structure provide useful information regarding the possible neurovascular involvement in the physiopathology of HD. Choroidal vascular network could be a useful parameter to evaluate the vascular impairment that occurs in this neurodegenerative disease

A 'erosão do solo' descrita em uma notícia: análise discursiva sobre a produção de sentidos envolvendo o ambiente rural.

A Análise de Discurso (AD) de linha francesa e a Análise Crítica de Discurso (ACD) fundamentam este estudo, que examina um enunciado jornalístico sobre os efeitos da erosão do solo na produção agrícola. A intenção é investigar como uma notícia sobre um problema típico do universo rural e/ou ambiental produz sentidos para interlocutores sem vínculos com o agronegócio. O enunciado apresenta sinais de polifonia, silenciamento e didaticidade que demarcam as condições de produção do texto, identificam endo/exogrupos, além de determinar uma linha de leitura, entre outras possíveis. A análise conclui que esse discurso não conecta o problema da degradação do solo ao consumidor final. O sentido é interrompido no elo da produção rural, como se os efeitos da degradação do solo sofressem uma descontinuidade, sem afetar itens que são consumidos por habitantes urbanos

Ambiguidades no discurso fotográfico: produção de sentido sobre a degradação do solo.

Com base em arcabouço teórico-metodológico que envolve os estudos do discurso e de imagem, analisa-se uma fotografia publicada em 2019, pelo Portal G1, que ilustra uma matéria sobre os efeitos da erosão do solo sobre a produção agrícola. Depreendem-se alguns sentidos pregnantes na enunciação imagética, considerando que as fotografias contribuem para informar, dão mais ênfase às reportagens e desempenham funções estéticas. Além disso, constituem sentidos que podem corroborar estereótipos e reificações acerca do universo rural, suas identidades e idiossincrasias. Infere-se, com este estudo, que o discurso fotográfico apresenta ambiguidade ao retratar um conteúdo que permite dupla leitura. A condução pela interpretação da ideia de desertificação se dá pelo elemento verbal da legenda. Como fotografias não transmitem conceitos abstratos, cabe ao interlocutor atribuir sentidos que se conectem ao seu repertório, num ato de reforço ou contradição à intencionalidade dos sujeitos enunciadores