Combining collaborative and content-based filtering to recommend research papers

The number of research papers available today is growing at a staggering rate, generating a huge amount of information that people cannot keep up with. According to a tendency indicated by the United States’ National Science Foundation, more than 10 million new papers will be published in the next 20 years. Because most of these papers will be available on the Web, this research focus on exploring issues on recommending research papers to users, in order to directly lead users to papers of their interest. Recommender systems are used to recommend items to users among a huge stream of available items, according to users’ interests. This research focuses on the two most prevalent techniques to date, namely Content-Based Filtering and Collaborative Filtering. The first explores the text of the paper itself, recommending items similar in content to the ones the user has rated in the past. The second explores the citation web existing among papers. As these two techniques have complementary advantages, we explored hybrid approaches to recommending research papers. We created standalone and hybrid versions of algorithms and evaluated them through both offline experiments on a database of 102,295 papers, and an online experiment with 110 users. Our results show that the two techniques can be successfully combined to recommend papers. The coverage is also increased at the level of 100% in the hybrid algorithms. In addition, we found that different algorithms are more suitable for recommending different kinds of papers. Finally, we verified that users’ research experience influences the way users perceive recommendations. In parallel, we found that there are no significant differences in recommending papers for users from different countries. However, our results showed that users’ interacting with a research paper Recommender Systems are much happier when the interface is presented in the user’s native language, regardless the language that the papers are written. Therefore, an interface should be tailored to the user’s mother language.

Assessment of the Ability to Relate Anterior Tooth Form and Arrangement to Gender

Purpose: This study evaluated the assumption that there are morphological differences between the natural anterior dentition of men and women. The goal of the study was to determine the gender of patients based on the appearance of the anterior teeth in photographs. Materials and Methods: Laymen and observers from different specialties were asked to determine the gender of individuals based on the shape and arrangement of anterior teeth. Forty anterior dentition photographs of dental students of both genders (20 women, 20 men) between 18 and 26 years old were selected, coded, and randomly arranged in an album. The albums were delivered to five groups of observers: general practitioners (recently graduated dentists), prosthodontists, orthodontists, restorative dentists (specialists in cosmetic and restorative dentistry), and laymen (control group). The observers evaluated the photographs twice at 1-week intervals. Results: The average correctly identified values in women and men were 57.6% and 58.8%, respectively. There was no statistical difference between observers and between each group of professionals and the laymen group (p > 0.05). An intraobserver agreement was not observed between the evaluations (kappa =-0.01). Conclusion: The results of this limited study indicated that it was not possible to differentiate gender by viewing photographs of anterior teeth.

Nonlinear Gravitational Waves: Their Form and Effects

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Functional Analysis for Gauge Fields on the Front-Form and the Light-Cone Gauge

Constrained systems in quantum field theories call for a careful study of diverse classes of constraints and consistency checks over their temporal evolution. Here we study the functional structure of the free electromagnetic and pure Yang-Mills fields on the front-form coordinates with the null-plane gauge condition. It is seen that in this framework, we can deal with strictu sensu physical fields.

Correlation between maxillary central incisor form and face form in 4 racial groups

Objectives: the purpose of this study was to evaluate the correlation between central incisor form and face form in 4 racial groups and to investigate if there was agreement among experts in categorizing the central incisor forms. Method and Materials: A total of 160 subjects (40 whites, 40 mulattos, 40 blacks, and 40 Asians) ranging from 18 to 33 years of age were selected. Digital photographic records were made, 1 full-face and 1 intraoral view of the maxillary right central incisor. The outline tracings of the tooth and face images were obtained using Adobe Photoshop 5.0 software. The outline tracings were printed in distinct transparencies, and 3 prosthodontists determined if there was correspondence between the tooth and the face forms by superimposition of the transparencies. If there was disagreement among the prosthodontists' evaluations, the prevalent decision was considered. The experts also classified the central incisor forms into square, ovoid, tapering, or combination at 2 different sessions. At the first session, no instructions were given. At the second session, the prosthodontists were instructed to follow Williams' method of classification. Results: A correspondence between tooth and face forms was found in 23.75% of all cases. Agreement on the tooth form classifications among the prosthodontists occurred in 30.62% of all cases at the first session and 24.37% at the second session. Conclusion: There is not a highly defined correlation between central incisor form and face form in any racial group studied. In addition, the experts were not in fair agreement in categorizing tooth forms.

Yeast proteins originated from the production of brazilian bioethanol quantification and content

The purpose of this work was to determine the levels of protein and the amino acid distribution in the cell mass of yeast strains (Saccharomyces sensu stricto) originated from Brazilian bioethanol industries. The protein was analyzed with the Kjeldahl method and the amino acids, by using high-performance liquid chromatography (HPLC). The percentages of the protein found ranged from 39 to 49%. The results show that in spite of some variation in numbers between the different yeast strains, all of them presented an amino acid profile similar to the one in the literature for S. cerevisae. The amino acids that have occurred in the largest amounts were: aspartic, glutamic acids and lysine, and those in the lowest amounts were: cysteine and methionine. Although the characteristics of the feedstock used and the process conditions are determinant of the protein values obtained in dry mass, this work elucidates that the intrinsic properties of the yeast strain influence these values.

Antinomia e expressão: Adorno ante o sismógrafo de Erwartung Op. 17 de Schoenberg

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A prática pedagógica da formação profissional por competências da modalidade aprendizagem do SENAI-PA

O presente trabalho, resultante de pesquisa documental e de campo, subsidiada pela abordagem qualitativa, teve por objetivos identificar e analisar a proposta metodológica de formação profissional por competências realizada pelo SENAI- PA, considerando suas especificidades, ideologias, objetivos latentes, e sua dimensão política, uma vez que esta instituição apresenta a referida proposta como alternativa para elevar o nível de formação e qualificação profissional, formar cidadãos criativos e empreendedores para atender às demandas do setor industrial. A investigação iniciou a partir de uma pesquisa exploratória e revisão bibliográfica de fundamentação teórica sobre a temática, permitindo a compreensão do objeto de estudo, além de respaldar a definição do problema de pesquisa. A pesquisa foi realizada a partir de informações contidas no site institucional do SENAI, de pesquisas e obras que tratam da formação profissional ofertada por esta instituição. Para a realização desta investigação foi feito primeiramente um estudo dos referenciais teóricos, sobretudo, das teorias pedagógicas que têm pautado o desenvolvimento da prática pedagógica no contexto educacional brasileiro, como também, das teorias pedagógicas e econômicas que têm fundamentado a prática pedagógica de educação profissional. À luz destes referenciais, e com base nos procedimentos da análise dos conteúdos, examinamos os dados a partir dos seguintes eixos temáticos: objetivos, avaliação conteúdos, métodos e técnicas de ensino, relação teoria e prática, forma e conteúdo. Utilizamos ainda as categorias de análise obtidas a partir dos dados coletados: aprendizagem significativa, prática pedagógica eficaz, formar para o trabalho e para cidadania. A pesquisa possibilitou identificar o utilitarismo no processo de ensino, cuja manifestação ocorre no desenrolar das práticas pedagógicas, através da relação dicotômica entre teoria e prática, caracterizando, desta forma, a proposta metodológica de ensino desta instituição. Verificamos que a atual metodologia de ensino fundamentada na pedagogia das competências, se constitui no aperfeiçoamento da antiga metodologia utilizada por esta instituição, uma vez que ambas estão alicerçadas no Condutivismo, Pragmatismo, Funcionalismo, e no Construtivismo. Este aperfeiçoamento vincula-se à investigação prévia das competências a serem adquiridas pelo trabalhador, à caracterização do perfil dos cursos pelas competências exigidas pelo mercado, à estreita relação dos elementos constitutivos da prática pedagógica - conteúdos, métodos e técnicas de ensino e a avaliação da aprendizagem - aos ditames mercadológicos. Constatamos ainda que este aperfeiçoamento promove a continuidade de uma formação orientada pelos preceitos e exigências do mercado, caracterizando uma formação profissional para o trabalho e para cidadania.

A relação entre conteúdo e forma nas políticas de educação profissional referenciadas no projeto de ensino médio integrado

Como objeto de estudo da presente pesquisa definimos a relação entre a concepção de Ensino Integrado e a forma de oferta de Ensino Médio Integrado à Educação Profissional expressa a partir do Decreto nº 5.154/2004 e que têm sido referência para as políticas públicas educacionais recentes na área da Educação Profissional. Nosso objetivo foi compreender a contradição que se impõe entre conteúdo e forma no Ensino Médio Integrado e o tratamento dado pelas políticas e programas baseados nessa concepção no que se refere à possível unidade entre estas duas dimensões que se configuram como ato educacional. Trata-se de um estudo de cunho bibliográfico e documental, no qual a análise do conteúdo foi utilizada para tratamento dos dados da pesquisa à luz de nossas categorias analíticas: a práxis e a totalidade. Como principais referências destacamos: Frigotto (2003, 2005 e 2006), Kuenzer (1991, 2007 e 2009), Ramos (2005, 2006), Frigotto, Ciavatta e Ramos (2005), Nosella (2004 e 2009), Marx (1844 e 1875), Manacorda (1991 e 2008), Vázquez (1976), Kosik (1926) e Pinto (2010). Destacamos entre os resultados o tratamento dissociado entre forma e conteúdo nas políticas e programas baseados na integração e a dificuldade de se construir uma política pública educacional que trate estas duas dimensões como uma unidade contribuindo assim para o efetivo rompimento da dualidade na educação.

Interpolating scattering amplitudes between the instant form and the front form of relativistic dynamics

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Scattering Amplitudes Interpolating Between Instant Form and Front Form of Relativistic Dynamics

Among the three forms of relativistic Hamiltonian dynamics proposed by Dirac in 1949, the front form has the largest number of kinematic generators. This distinction provides useful consequences in the analysis of physical observables in hadron physics. Using the method of interpolation between the instant form and the front form, we introduce the interpolating scattering amplitude that links the corresponding time-ordered amplitudes between the two forms of dynamics and provide the physical meaning of the kinematic transformations as they allow the invariance of each individual time-ordered amplitude for an arbitrary interpolation angle. We discuss the rationale for using front form dynamics, nowadays known as light-front dynamics (LFD), and present a few explicit examples of hadron phenomenology that LFD uniquely can offer from first-principles quantum chromodynamics. In particular, model-independent constraints are provided for the analyses of deuteron form factors and the N Delta transition form factors at large momentum transfer squared Q(2). The swap of helicity amplitudes between the collinear and non-collinear kinematics is also discussed in deeply virtual Compton scattering.

Local classification of singular hexagonal 3-webs with holomorphic Chern connection form and infinitesimal symmetries

Implicit ODE, cubic in derivative, generically has no infinitesimal symmetries even at regular points with distinct roots. Cartan showed that at regular points, ODEs with hexagonal 3-web of solutions have symmetry algebras of the maximal possible dimension 3. At singular points such a web can lose all its symmetries. In this paper we study hexagonal 3-webs having at least one infinitesimal symmetry at singular points. In particular, we establish sufficient conditions for the existence of non-trivial symmetries and show that under natural assumptions such a symmetry is semi-simple, i.e. is a scaling in some coordinates. Using the obtained results, we provide a complete classification of hexagonal singular 3-web germs in the complex plane, satisfying the following two conditions: 1) the Chern connection form is holomorphic at the singular point, 2) the web admits at least one infinitesimal symmetry at this point. As a by-product, a classification of hexagonal weighted homogeneous 3-webs is obtained.