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

Isolated Paralysis of the Adductor Pollicis: A Case Report

We report a case of isolated paralysis of the right adductor pollicis in a 30-year-old woman. Electromyographic study showed involvement of the deep motor branch of the ulnar nerve. A ganglion and an anomalous muscle were both ruled out clinically and by MRI as a possible cause of the paralysis. At surgical exploration, we found a fibrous band joining the pisiform and the hook of the hamate bone that compressed the deep motor branch of the ulnar nerve. The fibrous band was excised, and a neurolysis of the motor branch of the ulnar nerve was performed. At followup, eight months later, the patient had fully recovered strength of the adductor muscle

Fostering savings by commitment: Evidence from a quasi-natural experiment at The Small Enterprise Foundation in South Africa

We studied the effects of a pilot project that strengthened savings incentive mechanisms. The project was established by The Small Enterprise Foundation (SEF), a leading microfinance institution based in South Africa. The program introduced a savings stimulus in the form of a Goal Card: clients subscribing to this (non-coercive) tool were required to identify a savings goal and to commit to regular payments to reach it. The experiment had a quasi-natural approach as it was implemented by SEF in non-randomly selected locations. Difference-in-differences estimates show improved savings habits among those of the foundation's customers who were involved in the program, compared to the counterfactual that are identified using propensity score matching. The effect of the program manifested in its second semester, suggesting a persistent change of habits but a slow accumulation of savings. We conclude that asking microcredit customers to identify a savings goal and commit to a regular savings amount to achieve it is a promising savings incentive mechanism

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

In vivo manipulation of the extracellular matrix induces vascular regression in a basal chordate.

We investigated the physical role of the extracellular matrix (ECM) in vascular homeostasis in the basal chordate Botryllus schlosseri, which has a large, transparent, extracorporeal vascular network encompassing an area >100 cm2 We found that the collagen cross-linking enzyme lysyl oxidase is expressed in all vascular cells and that in vivo inhibition using β-aminopropionitrile (BAPN) caused a rapid, global regression of the entire network, with some vessels regressing >10 mm within 16 h. BAPN treatment changed the ultrastructure of collagen fibers in the vessel basement membrane, and the kinetics of regression were dose dependent. Pharmacological inhibition of both focal adhesion kinase (FAK) and Raf also induced regression, and levels of phosphorylated FAK in vascular cells decreased during BAPN treatment and FAK inhibition but not Raf inhibition, suggesting that physical changes in the vessel ECM are detected via canonical integrin signaling pathways. Regression is driven by apoptosis and extrusion of cells through the basal lamina, which are then engulfed by blood-borne phagocytes. Extrusion and regression occurred in a coordinated manner that maintained vessel integrity, with no loss of barrier function. This suggests the presence of regulatory mechanisms linking physical changes to a homeostatic, tissue-level response

Radiographic classification of coronal plane femoral deformities in polyostotic fibrous dysplasia

Fibrous dysplasia of bone is a skeletal dysplasia with a propensity to affect the femur in its polyostotic form, leading to deformity, fracture, and pain. The proximal femur is most commonly involved with a tendency to distal progression, thereby producing the typical shepherd's crook deformity. However, there are few data on the spectrum and progression of femoral deformities in polyostotic fibrous dysplasia

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