Shack-Hartmann wave front measurements in cortical tissue for deconvolution of large three-dimensional mosaic transmitted light brightfield micrographs

We present a novel approach for deconvolution of 3D image stacks of cortical tissue taken by mosaic/optical-sectioning technology, using a transmitted light brightfield microscope. Mosaic/optical-sectioning offers the possibility of imaging large volumes (e.g. from cortical sections) on a millimetre scale at sub-micrometre resolution. However, a blurred contribution from out-of-focus light results in an image quality that usually prohibits 3D quantitative analysis. Such quantitative analysis is only possible after deblurring by deconvolution. The resulting image quality is strongly dependent on how accurate the point spread function used for deconvolution resembles the properties of the imaging system. Since direct measurement of the true point spread function is laborious and modelled point spread functions usually deviate from measured ones, we present a method of optimizing the microscope until it meets almost ideal imaging conditions. These conditions are validated by measuring the aberration function of the microscope and tissue using a Shack-Hartmann sensor. The analysis shows that cortical tissue from rat brains embedded in Mowiol and imaged by an oil-immersion objective can be regarded as having a homogeneous index of refraction. In addition, the amount of spherical aberration that is caused by the optics or the specimen is relatively low. Consequently the image formation is simplified to refraction between the embedding and immersion medium and to 3D diffraction at the finite entrance pupil of the objective. The resulting model point spread function is applied to the image stacks by linear or iterative deconvolution algorithms. For the presented dataset of large 3D images the linear approach proves to be superior. The linear deconvolution yields a significant improvement in signal-to-noise ratio and resolution. This novel approach allows a quantitative analysis of the cortical image stacks such as the reconstruction of biocytin-stained neuronal dendrites and axons

The Effects of Digital Technology on Opportunity Recognition

Recognizing opportunities enabled by digital technology (DT) has become a competitive necessity in today’s digital world. However, opportunity recognition is a major challenge given the influence of DT, which not only disperses agency across various actors, but also blurs boundaries between customers, companies, products, and industries. As a result, traditional entrepreneurship knowledge needs to be rethought and the effects of DT on opportunity recognition need to be better understood. Drawing from opportunity recognition theory – as one of the central theories in the entrepreneurship domain – this study builds on a structured literature review to identify and explain three direct as well as three transitive effects of DT on opportunity recognition. These effects have been validated with real-world cases as well as interviews with academics and practitioners. In sum, this study contributes to descriptive and explanatory knowledge on the evolution from traditional to digital entrepreneurship. As a theory for explaining, the findings extend opportunity recognition theory by illuminating how and why DT influences opportunity recognition. This supports research and practice in investigating and managing opportunities more effectively

A inter-relação entre a história da arte e a restauração: a Igreja da Ordem III de São Francisco da Penitência - um estudo de caso

Initially, the question proposes to focus the influence of the taste and values of the society at each age, about the artist and the restorer's tendencies. Sequentially, the Ordem III de São Francisco da Penitência Church of Rio de Janeiro will be presented as a case study, which deals with the necessity of doing some research, through the survey of prerequisites referring to the artistic- historical values and interventions. Afterwards, the importance of the Art's History will be restated, as the main reference to select the criteria, which will be applied to the restoration of the work of art.A questão propõe, inicialmente, enfocar a influência do gosto e dos valores da sociedade de cada época, nas trajetórias do artista e do restaurador. Em sequência, será apresentada a Igreja da Ordem III de são Francisco da Penitência do Rio de Janeiro, como um estudo de caso, abordando a necessidade da realização de pesquisa, através do levantamento de dados referentes aos valores histórico- artísticos e de intervenções. E, a seguir, será reafirmada a importância da História da Arte, como principal referencial, na seleção dos critérios a serem aplicados na recuperação da obra de arte

Understanding the Internet of Things: A Conceptualisation of Business-to-Thing (B2T) Interactions

The Internet of Things is widely regarded as one of the most disruptive technologies as it integrates Internet-enabled physical objects into the networked society and makes these objects increasingly autonomous partners in digitised value chains. After transforming internal processes and enhancing efficiency, the Internet of Things yields the potential to transform traditional business-to-customer interactions in a way previously not thought of. Remote patient monitoring, predictive maintenance, and automatic car repair are only some innovative examples. This paper contributes to the conceptualisation of the emerging business relationships based on such empowered smart things by proposing a series of core and advanced business-to-thing (B2T) interaction patterns. The core patterns named C2T-Only, B2T-Only, Customer-Centred, Business-Centred, Thing-Centred, and All-In B2T classify alternative interactions between businesses, customers, and smart things, using the connected car as an ongoing case and Uber as an example to demonstrate how patters can be composed. The proposed patterns demonstrate the affordances of integrating smart things into the networked society and sensitise for the emergence of B2T interactions

3D Reconstruction and Standardization of the Rat Vibrissal Cortex for Precise Registration of Single Neuron Morphology

Author Summary For studying the neural basis of perception and behavior, it would be ideal to directly monitor sensory-evoked excitation streams within neural circuits, at sub-cellular and millisecond resolution. To do so, reverse engineering approaches of reconstructing circuit anatomy and synaptic wiring have been suggested. The resulting anatomically realistic models may then allow for computer simulations (in silico experiments) of circuit function. A natural starting point for reconstructing neural circuits is a cortical column, which is thought to be an elementary functional unit of sensory cortices. In the vibrissal area of rodent somatosensory cortex, a cytoarchitectonic equivalent, designated as a ‘barrel column’, has been described. By reconstructing the 3D geometry of almost 1,000 barrel columns, we show that the somatotopic layout of the vibrissal cortex is highly preserved across animals. This allows generating a standard cortex and registering neuron morphologies, obtained from different experiments, to their ‘true’ location. Marking a crucial step towards reverse engineering of cortical circuits, the present study will allow estimating synaptic connectivity within an entire cortical area by structural overlap of registered axons and dendrites

Reposicionamento de produto: um estudo de caso da gasolina aditivada nova Shell V-power

Nos últimos anos, com o aumento nas vendas dos carros bi-combustíveis, o que gerou uma maior penetração do álcool na matriz energética, bem como a desregulamentação do setor de combustíveis, possibilitando um aumento do número de distribuidoras, a margem das companhias que atuam neste setor está ameaçada. Em se tratando do mercado de combustíveis brasileiro, onde praticamente não existem concorrentes para a Petrobrás no refino da gasolina, é fato que as demais distribuidoras deste mercado compram quase que toda a gasolina desta. As principais conseqüências disto são as margens de lucro reduzidas e principalmente, a dificuldade de diferenciação dos produtos. Uma das formas para diferenciar-se no setor e ainda, obter margens superiores é através das gasolinas aditivadas. Sendo assim, este trabalho tentou analisar como a empresa Shell Brasil Ltda. busca se diferenciar da concorrência no mercado de Varejo de combustíveis. Através de um estudo de caso da gasolina aditivada nova Shell V-Power, que passou recentemente por um reposicionamento do produto, analisou-se por que a Shell optou por reposicionar este produto, quais os desafios enfrentados, as mudanças adotadas e as principais oportunidades e ameaças futuras

The impact of neuron morphology on cortical network architecture

The neurons in the cerebral cortex are not randomly interconnected. This specificity in wiring can result from synapse formation mechanisms that connect neurons, depending on their electrical activity and genetically defined identity. Here, we report that the morphological properties of the neurons provide an additional prominent source by which wiring specificity emerges in cortical networks. This morphologically determined wiring specificity reflects similarities between the neurons’ axo-dendritic projections patterns, the packing density, and the cellular diversity of the neuropil. The higher these three factors are, the more recurrent is the topology of the network. Conversely, the lower these factors are, the more feedforward is the network’s topology. These principles predict the empirically observed occurrences of clusters of synapses, cell type-specific connectivity patterns, and nonrandom network motifs. Thus, we demonstrate that wiring specificity emerges in the cerebral cortex at subcellular, cellular, and network scales from the specific morphological properties of its neuronal constituents

former title: A theory for the emergence of neocortical network architecture

Developmental programs that guide neurons and their neurites into specific subvolumes of the mammalian neocortex give rise to lifelong constraints for the formation of synaptic connections. To what degree do these constraints affect cortical wiring diagrams? Here we introduce an inverse modeling approach to show how cortical networks would appear if they were solely due to the spatial distributions of neurons and neurites. We find that neurite packing density and morphological diversity will inevitably translate into non-random pairwise and higher-order connectivity statistics. More importantly, we show that these non-random wiring properties are not arbitrary, but instead reflect the specific structural organization of the underlying neuropil. Our predictions are consistent with the empirically observed wiring specificity from subcellular to network scales. Thus, independent from learning and genetically encoded wiring rules, many of the properties that define the neocortex’ characteristic network architecture may emerge as a result of neuron and neurite development

An Update for Taxonomy Designers

Taxonomies are classification systems that help researchers conceptualize phenomena based on their dimensions and characteristics. To address the problem of ‘ad-hoc’ taxonomy building, Nickerson et al. (2013) proposed a rigorous taxonomy development method for information systems researchers. Eight years on, however, the status quo of taxonomy research shows that the application of this method lacks consistency and transparency and that further guidance on taxonomy evaluation is needed. To fill these gaps, this study (1) advances existing methodological guidance and (2) extends this guidance with regards to taxonomy evaluation. Informed by insights gained from an analysis of 164 taxonomy articles published in information systems outlets, this study presents an extended taxonomy design process together with 26 operational taxonomy design recommendations. Representing an update for taxonomy designers, it contributes to the prescriptive knowledge on taxonomy design and seeks to augment both rigorous taxonomy building and evaluation