7,752 research outputs found
Nonlinear Hebbian learning as a unifying principle in receptive field formation
The development of sensory receptive fields has been modeled in the past by a
variety of models including normative models such as sparse coding or
independent component analysis and bottom-up models such as spike-timing
dependent plasticity or the Bienenstock-Cooper-Munro model of synaptic
plasticity. Here we show that the above variety of approaches can all be
unified into a single common principle, namely Nonlinear Hebbian Learning. When
Nonlinear Hebbian Learning is applied to natural images, receptive field shapes
were strongly constrained by the input statistics and preprocessing, but
exhibited only modest variation across different choices of nonlinearities in
neuron models or synaptic plasticity rules. Neither overcompleteness nor sparse
network activity are necessary for the development of localized receptive
fields. The analysis of alternative sensory modalities such as auditory models
or V2 development lead to the same conclusions. In all examples, receptive
fields can be predicted a priori by reformulating an abstract model as
nonlinear Hebbian learning. Thus nonlinear Hebbian learning and natural
statistics can account for many aspects of receptive field formation across
models and sensory modalities
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Agency, Liberation, and Intersectionality among Latina Scholars: Narratives from a Cross-institutional Writing Collective
Among United States residents, the number of doctoral degrees conferred to Latinx students represents a small percentage compared to other groups. For example, from 2009–2010, the percentage of degrees conferred to Latinx students was 5 percent compared to 74 percent for White students, 11 percent for Asian/Pacific Islanders, 7 percent for African Americans, and 0.7 percent for Indian/Alaska Natives. During the same period, the proportion of doctoral degrees conferred to females was 55 percent for Latinas compared to 65 percent for African American students, 56 percent for Asian/Pacific students, 54 percent for American Indian/Alaska Native students, and 51 percent for White female students (National Center for Education Statistics). Historically, underrepresented minority (URM) students encounter a plethora of issues that influence their educational experiences, yet there is a scarcity of scholarship that elucidates the quality of experience of women of color (WOC) pursuing doctorate degrees (Aryan and Guzman). As multi-marginalized, firstgeneration college students, we continuously struggle to find a place within higher education. Our educational pathways to becoming doctoral recipients have occurred primarily within the context of alienation, significantly influencing our need to connect with other WOC who have also felt isolated and disconnected. Consequently, we needed to find each other because knowing that there were other Latinas in doctoral programs, and actually getting to know them, validated our existence within academiaUniversity Writing Cente
Scrum solo application in a project with a strong integration component
In Portugal, 90% of software developing companies are micro companies. In 2002, in the Brazilian market, about 60% of the software developing companies would start their activities with just a single developer (Pagotto, Fabrti, Lerario, and Gonçalves, 2016). The Scrum Solo methodology was developed having in mind, that there is a big need for organizing and managing the software development of teams comprised by a single individual. The underlying complexity of big systems and the underlying integration complexity makes the usage of techniques and processes that guarantee the control of the project vital. The methodology described in this document is validated with two application cases in a context of development. The first one is an extensive project, with strong integration component, and the second one the development of an application for process dematerialization. The Scrum Solo methodology performed well in both cases despite their differences. Nevertheless, more cases should be analysed with the emphasis in using different contexts namely other organizations.FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/202
Academic performance of Brazilian middle school children as assessed by an adaptation of the wide range achievement test (WRAT 3)
OBJETIVOS: examinar o desempenho acadêmico de escolares brasileiros do 6º. ao 9º. ano através de uma adaptação das formas Azul e Marrom do Wide Range Achievement Test (WRAT3-TDA3). MÉTODO: o desempenho de 722 escolares (281 meninos e 441 meninas com idade média de 13,5 anos, DP= 1,4) foi avaliado. Os dados foram analisados através de uma análise multivariada de variância para determinar a relação entre o desempenho no Ditado, Aritmética e Leitura e caracterÃsticas demográficas das crianças, história de repetência, dominância manual, e disfunção auditiva e visual. RESULTADOS: a forma do teste (Azul e Marrom) teve um efeito significativo e, por isso, os dados foram examinados separadamente para cada forma do TDA3. Demonstrou-se que o sexo, idade, etnia, ocupação materna e paterna, história de repetência e disfunção auditiva e visual estavam significativamente associados ao desempenho nos subtestes Ditado, Aritmética e Leitura de ambas as formas. Além disso, a idade e dominância manual apresentaram efeitos significativos no desempenho dos subtestes da forma Azul e escolares com disfunção auditiva ou visual mostraram um desempenho pior nos subtestes da forma Marrom em comparação com os escolares sem qualquer disfunção. CONCLUSÃO: é possÃvel que o perfil do desempenho acadêmico dos escolares documentado no presente estudo esteja relacionado com aspectos fundamentais da linguagem e pesquisa nesta direção está atualmente em andamento.OBJECTIVE: to assess the academic performance of Brazilian children by an adaptation of the Blue and Tan forms of the WRAT3 (Brazil - WRAT 3). METHODS: the performance of 722 children (281 boys and 441 girls with mean age of 13.5 years, SD = 1.4) was evaluated. The data were subjected to multivariate statistical analysis to determine the relationships between performance on Spelling, Arithmetic and Reading and demographic characteristics of the children, history of grade failure, handedness, and auditory and visual dysfunction. RESULTS: the form (Blue vs Tan) of the test had a significant effect on performance and so the data were analyzed separately for each form of the Brazil-WRAT3. It was found that sex, ethnic group, paternal and maternal occupation and history of the grade failure were significantly related to performance on Spelling, Arithmetic and Reading of both forms. Furthermore, age and handedness had significant effects on the overall performance of the subtests of the Blue form and children with auditory or visual dysfunction performed the subtests of the Tan form worse than normal children. CONCLUSION: it is possible that the profile of the academic performance of Brazilian public school children shown in this study is associated with more fundamental aspects of language skills and research along this direction is currently underway
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