Quantifier-Free Interpolation of a Theory of Arrays

The use of interpolants in model checking is becoming an enabling technology to allow fast and robust verification of hardware and software. The application of encodings based on the theory of arrays, however, is limited by the impossibility of deriving quantifier- free interpolants in general. In this paper, we show that it is possible to obtain quantifier-free interpolants for a Skolemized version of the extensional theory of arrays. We prove this in two ways: (1) non-constructively, by using the model theoretic notion of amalgamation, which is known to be equivalent to admit quantifier-free interpolation for universal theories; and (2) constructively, by designing an interpolating procedure, based on solving equations between array updates. (Interestingly, rewriting techniques are used in the key steps of the solver and its proof of correctness.) To the best of our knowledge, this is the first successful attempt of computing quantifier- free interpolants for a variant of the theory of arrays with extensionality

Unexpected thymoma in a challenging case of hyperparathyroidism

We report the case of a woman with primary hyperparathyroidism suspected of mediastinal ectopic parathyroid adenoma revealed to be a thymoma. Our aim was to focus on some possible criticisms in distinguishing between ectopic parathyroid and thymus

Bioreactor With Electrically Deformable Curved Membranes for Mechanical Stimulation of Cell Cultures.

Physiologically relevant in vitro models of stretchable biological tissues, such as muscle, lung, cardiac and gastro-intestinal tissues, should mimic the mechanical cues which cells are exposed to in their dynamic microenvironment in vivo. In particular, in order to mimic the mechanical stimulation of tissues in a physiologically relevant manner, cell stretching is often desirable on surfaces with dynamically controllable curvature. Here, we present a device that can deform cell culture membranes without the current need for external pneumatic/fluidic or electrical motors, which typically make the systems bulky and difficult to operate. We describe a modular device that uses elastomeric membranes, which can intrinsically be deformed by electrical means, producing a dynamically tuneable curvature. This approach leads to compact, self-contained, lightweight and versatile bioreactors, not requiring any additional mechanical equipment. This was obtained via a special type of dielectric elastomer actuator. The structure, operation and performance of early prototypes are described, showing preliminary evidence on their ability to induce changes on the spatial arrangement of the cytoskeleton of fibroblasts dynamically stretched for 8 h

Bioreactor With Electrically Deformable Curved Membranes for Mechanical Stimulation of Cell Cultures

Physiologically relevant in vitro models of stretchable biological tissues, such as muscle, lung, cardiac and gastro-intestinal tissues, should mimic the mechanical cues which cells are exposed to in their dynamic microenvironment in vivo. In particular, in order to mimic the mechanical stimulation of tissues in a physiologically relevant manner, cell stretching is often desirable on surfaces with dynamically controllable curvature. Here, we present a device that can deform cell culture membranes without the current need for external pneumatic/fluidic or electrical motors, which typically make the systems bulky and difficult to operate. We describe a modular device that uses elastomeric membranes, which can intrinsically be deformed by electrical means, producing a dynamically tuneable curvature. This approach leads to compact, self-contained, lightweight and versatile bioreactors, not requiring any additional mechanical equipment. This was obtained via a special type of dielectric elastomer actuator. The structure, operation and performance of early prototypes are described, showing preliminary evidence on their ability to induce changes on the spatial arrangement of the cytoskeleton of fibroblasts dynamically stretched for 8 h

Registros de moluscos gastrópodes do Grupo Bauru (Bacia Bauru, Cretáceo Superior), nos estados de São Paulo e Minas Gerais, Brasil

Dentre os fósseis do Grupo Bauru (Cretáceo Superior, Bacia Bauru, Brasil), certamente os mais conhecidos são os répteis crocodilianos, quelônios e dinossaurídeos. Contudo, outros macrofósseis podem ser descritos para esses sedimentos como vegetais, ostrácodes, conchostráceos e restos de peixes. São os moluscos, entretanto, o táxon menos estudado do Grupo Bauru, sendo os poucos trabalhos existentes versando sobre a sistemática do grupo. Aqui se tenta fazer uma revisão de Gastropoda do Cretáceo da Bacia Bauru e descrição de novos locais de coleta dentro do estado de São Paulo. Para o estado de Minas Gerais são descritos táxons das ordens Mesogastropoda (Turritella sp.) e Caenogastropoda (Hydrobia sp.), ambos encontrados nas cercanias do município de Uberaba. Já para o estado de São Paulo encontram-se táxons das ordens Basommathophora (Physa aridi Mezzalira), no município de São José de Rio Preto, e Caenogastropoda (?Hydrobia prudentinensis Mezzalira), no município de Presidente Prudente. Recentes trabalhos de campo, entretanto, aumentaram a área de abrangência dos gastrópodes para o estado de São Paulo. Duas novas espécies de Physidae são descritas para os municípios de Marília (22°20'2''S e 49º56'41''O) e Presidente Prudente (22°07'0''S e 51°26'30''O) além de uma nova espécie de Hydrobiidae no município de Presidente Prudente (22°19'88''S e 50°09'30''O). Todos os fósseis pertencem litologicamente a Formação Adamantina. A descoberta de novos pontos de coletas e de novas espécies de gastrópodes demonstra a falta e a necessidade de estudos realizados para esse grupo que apresenta um papel de indicador paleoambiental importante para o melhor entendimento das condições de deposição do Grupo Bauru.Sesiones libresFacultad de Ciencias Naturales y Muse

Altered dynamics of visual contextual interactions in Parkinson\u27s disease.

Over the last decades, psychophysical and electrophysiological studies in patients and animal models of Parkinson\u27s disease (PD), have consistently revealed a number of visual abnormalities. In particular, specific alterations of contrast sensitivity curves, electroretinogram (ERG), and visual-evoked potentials (VEP), have been attributed to dopaminergic retinal depletion. However, fundamental mechanisms of cortical visual processing, such as normalization or gain control computations, have not yet been examined in PD patients. Here, we measured electrophysiological indices of gain control in both space (surround suppression) and time (sensory adaptation) in PD patients based on steady-state VEP (ssVEP). Compared with controls, patients exhibited a significantly higher initial ssVEP amplitude that quickly decayed over time, and greater relative suppression of ssVEP amplitude as a function of surrounding stimulus contrast. Meanwhile, EEG frequency spectra were broadly elevated in patients relative to controls. Thus, contrary to what might be expected given the reduced contrast sensitivity often reported in PD, visual neural responses are not weaker; rather, they are initially larger but undergo an exaggerated degree of spatial and temporal gain control and are embedded within a greater background noise level. These differences may reflect cortical mechanisms that compensate for dysfunctional center-surround interactions at the retinal level

Visuospatial exploration and art therapy intervention in patients with Parkinson's disease: an exploratory therapeutic protocol

Abstract Though abnormalities of visuospatial function occur in Parkinson's disease, the impact of such deficits on functional independence and psychological wellbeing has been historically under- recognized, and effective treatments for this impairment are unknown. These symptoms can be encountered at any stage of the disease, affecting many activities of daily living, and negatively influencing mood, self-efficacy, independence, and overall quality of life. Furthermore, visuospatial dysfunction has been recently linked to gait impairment and falls, symptoms that are known to be poor prognostic factors. Here, we aim to present an original modality of neurorehabilitation designed to address visuospatial dysfunction and related symptoms in Parkinson's disease, known as "Art Therapy". Art creation relies on sophisticated neurologic mechanisms including shape recognition, motion perception, sensory-motor integration, abstraction, and eye-hand coordination. Furthermore, art therapy may enable subjects with disability to understand their emotions and express them through artistic creation and creative thinking, thus promoting self-awareness, relaxation, confidence and self-efficacy. The potential impact of this intervention on visuospatial dysfunction will be assessed by means of combined clinical, behavioral, gait kinematic, neuroimaging and eye tracking analyses. Potential favorable outcomes may drive further trials validating this novel paradigm of neurorehabilitation