A waypoint-based mission planner for a farmland coverage with an aerial robot - a precision farming tool

Remote sensing (RS) with aerial robots is becoming more usual in every day time in Precision Agriculture (PA) practices, do to their advantages over conventional methods. Usually, available commercial platforms providing off-the-shelf waypoint navigation are adopted to perform visual surveys over crop fields, with the purpose to acquire specific image samples. The way in which a waypoint list is computed and dispatched to the aerial robot when mapping non empty agricultural workspaces has not been yet discussed. In this paper we propose an offline mission planner approach that computes an efficient coverage path subject to some constraints by decomposing the environment approximately into cells. Therefore, the aim of this work is contributing with a feasible waypoints-based tool to support PA practice

Disonancias pedagógicas en la resolución de problemas de física : una propuesta para su superación de raíz vygotskiana

Based on Vygotsky's thinking, this paper aims at analysing the number of difficulties students usually experience when trying to cope with problem solving in physics. Both cognitive and metacognitive considerations and affective ones are explored. Some empirical evidence (both quantitative and qualitative), taken from a broad metacognitively oriented field study, is taken into account. The empirical part of this study was carried out in the field of physics, at two Portuguese high schools (tenth grade students), being supported by an experimental versus control design. The analysis of data seems to indicate significantly higher progress for the experimental pupils as compared with their control peers. Our claim that a metacognitively oriented approach might be a suitable means to overcome some of the pedagogical dissonances that typically affect problem solving in physics seems to have acquired considerable support

Neural Substrates of Chronic Pain in the Thalamocortical Circuit

Chronic pain (CP), a pathological condition with a large repertory of signs and symptoms, has no recognizable neural functional common hallmark shared by its diverse expressions. The aim of the present research was to identify potential dynamic markers shared in CP models, by using simultaneous electrophysiological extracellular recordings from the rat ventrobasal thalamus and the primary somatosensory cortex. We have been able to extract a neural signature attributable solely to CP, independent from of the originating conditions. This study showed disrupted functional connectivity and increased redundancy in firing patterns in CP models versus controls, and interpreted these signs as a neural signature of CP. In a clinical perspective, we envisage CP as disconnection syndrome and hypothesize potential novel therapeutic appraisal

O repositório de conteúdo digital nas pesquisas de história da educação matemática

Disponível em: http://ojs.fe.unicamp.br/index.php/RIDPHE-R/article/view/7307/6232Este texto apresenta o Repositório de Conteúdo Digital utilizado pelo GHEMAT – Grupo de Pesquisa de História da Educação Matemática. Este espaço virtual, sediado fisicamente na Universidade Federal de Santa Catarina, abriga as digitalizações dos documentos mobilizados nos projetos em andamento deste grupo de pesquisa. O seu uso tem se demonstrado profícuo pois permite o compartilhamento destas fontes em diversas localidades, potencializando as pesquisas em caráter histórico comparativas realizadas por projetos temáticos envolvendo grande número de pesquisadores nos diversos estados brasileiros. Por fim, são apresentados alguns exemplos de produções acadêmicas do grupo de pesquisa apoiados no uso do Repositório, tanto do ponto de vista de sua elaboração/produção assim como posterior divulgação/publicação

Enhanced lipid extraction from unbroken microalgal cells using enzymes

The marine microalga Nannochloropsis sp. was chosen as a model organism to investigate the feasibility of using cell wall-degrading enzymes to enhance the recovery of intracellular lipids. An enzyme cocktail containing galactomannanase, 1,4-β-cellobiosidase and β-glucosidase as main components was prepared from commercial enzyme preparations. The effects of pretreatment time (P), enzyme dosage (D), pH and temperature (T) on the amount of extracted lipids were investigated using response surface methodology. Under the best conditions (P = 90 min, D = 1.3 mg g–1, pH = 5, T = 36°C) over 70% of the lipids present in the microalga were recovered. SEM and TEM characterization of enzyme-treated microalgae showed extensive cell damage with significant disruption of the cell wall and release of algal material. Overall, the results of this study strongly support the use of commercial enzyme preparations to improve lipid recovery from microalgae and provide useful information on the influence of process conditions on the treatment efficiency

Cerebrospinal fluid fistulas after iliosacral screw removal in post-traumatic pseudomeningocele

Sacral fractures are rare but severe injuries. They are often associated with neurological impairment and pelvic instability. We present a case of a 28-year-old woman who sustained an H-type fracture of the sacrum with complete cauda equina syndrome treated with cauda equina decompression and pelvic percutaneous stabilization with an iliosacral screw. Two years after she underwent screw removal, but complained of back and nape pain after the operation. A lumbosacral MRI showed the presence of a lytic lesion involving the S1 and S2 bodies that was judged to be a pseudomeningocele leaning against the sacral screw hole and cerebrospinal fluid fistulas through this. To our knowledge, this is the first case of such a complication after sacral screw removal to be reported

What is the optimal stitching orientation from an aerial survey perspective?

Mosaicing is a technique that allows obtaining a large high resolution image by stitching several images together. These base images are usually acquired from an elevated point of view. Until recently, low-altitude image acquisition has been performed typically by using using airplanes, as well as other manned platforms. However, mini unmanned aerial vehicles (MUAV) endowed with a camera have lately made this task more available for small for cicil applications, for example for small farmers in order to obtain accurate agronomic information about their crop fields. The stitching orientation, or the image acquisition orientation usually coincides with the aircraft heading assuming a downwards orientation of the camera. In this paper, the efect of the image orientation in the eficiency of the aerial coverage path planning is studied. Moreover, an algorithm to compute an optimal stitching orientation angle is proposed and results are numerically compared with classical approaches

Dose point kernel calculation and modelling with nuclear medicine dosimetry purposes

Trabajo presentado en el X Latin American Symposium on Nuclear Physics and Applications (X LASNPA), 1-6 diciembre 2013. Montevideo, Uruguay.Monoclonal labeled antibodies are commonly used for radioimmunotherapy purposes in nuclear medicine. The procedure is based on the deposition of specific radiactivity concentrations on tumoral regions with the aim of treating tumoral diseases. Patient metabolism produces nonuniform organ activity distributions, but there are some traditional approaches for internal dosimetry assuming uniform spatial distribution of activity within organ or tissues of interest. When patient-specific dosimetry needs to be performed, these methods may involve non negligible uncertainties. Treatment evaluation and preliminary planning require the estimation of absorbed dose distribution and this goal can be achieved by different approaches. For example, it is possible to perform Monte Carlo simulations for numerical dose assessments; whereas analytical calculations can be carried out by convolution of activity distribution using Dose Point Kernels. Besides, it is often found that some internal dosimetry approaches assume simplified conditions of infinite ad homogeneous media for radiation transport and corresponding dose deposition. This work presents a method for internal dosimetry in nuclear medicine by means of Dose Point Kernels. The proposed method is capable of performing calculations over heterogeneous systems. The starting point is a set of suitable kernels previously calculated by Monte Carlo simulations in different tissues. Thus, dose distribution is obtained by the proposed hybrid approach involving both numerical and analytical methods. Preliminary tests on simplified geometries demonstrated the capability of the developed technique; whereas computation of patient-specific internal dosimetry suggest promising performance. Hence, the developed method may constitute a valuable tool for nuclear medicine dosimetry purposes.publishedVersionFil: Scarinci, Ignacio Emanuel. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física. Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X; Argentina.Fil: Valente, Mauro Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Valente, Mauro Andrés. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física. Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X; Argentina.Fil: Pérez, Pedro Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Pérez, Pedro Antonio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física. Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X; Argentina.Fil: Pérez, Pedro Antonio. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Físico-Químicas y Naturales. Departamento de Física; Argentina.Física Atómica, Molecular y Química (física de átomos y moléculas incluyendo colisión, interacción con radiación, resonancia magnética, Moessbauer Efecto.

Internal dosimetry for alpha emitters radiopharmaceuticals in biological tissue studied with the FLUKA code

Trabajo presentado en el X Latin American Symposium on Nuclear Physics and Applications (X LASNPA), 1-6 diciembre 2013. Montevideo, Uruguay.Nuclear medicine clinical practices for neoplasic disease diagnose and treatment are based on the incorporation of α, β and γ radiotracers and radiopharmaceuticals, which might be associated with potential damage. Thus, being necessary accurate dosimetry strategies. In vivo absorbed dose appears as an ideal solution. However, its implementation in clinics does not attain enough reliability. In this sense, different approaches were proposed for internal dosimetry calculations. This work presents a novel analytical-numerical approach for internal dosimetry purposes. Dedicated Monte Carlo simulations were performed by subroutines adapted from the FLUKA code. In-water EDK were evaluated at different photon energies and some typical γ-emitters radiopharmaceuticals; whereas DPK were obtained for both α- and β- emitters. Additionally, EDK and DPK were calculated for several biological tissues.publishedVersionFil: Valente, Mauro Andrés. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Valente, Mauro Andrés. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Física Enrique Gaviola; Argentina.Fil: Valente, Mauro Andrés. Universidad Nacional de Córdoba. Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X; Argentina.Fil: Malano, Francisco Mauricio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Malano, Francisco Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Malano, Francisco Mauricio. Universidad Nacional de Córdoba. Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X; Argentina.Fil: Pérez, Pedro Antonio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Pérez, Pedro Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Pérez, Pedro Antonio. Universidad Nacional de Córdoba. Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X; Argentina.Física Atómica, Molecular y Química (física de átomos y moléculas incluyendo colisión, interacción con radiación, resonancia magnética, Moessbauer Efecto.

“You see yourself like in a mirror”: the effects of internet-mediated personal networks on body image and eating disorders

Body image issues associated with eating disorders consist of attitudinal and perceptual components: individuals’ dissatisfaction with body shape or weight, and inability to correctly assess body size. While prior research has mainly explored social pressure from media, fashion, and advertising, we aim to uncover how personal networks, also encompassing internet-mediated interactions, bear upon body image. We estimate these effects with data from a survey of users of websites on eating disorders, including indicators of their body size and body image, and maps of their networks of connections. A bivariate ordered probit accounts for the joint distribution of attitudinal and perceptual body image dimensions depending on network characteristics. Results, confirmed by in-depth interviews, provide evidence that personal networks affect body image concerns, and show that this influence varies significantly by body size. Personal networks, as may be formed also (but not only) online, can be conducive to positive body image development