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Concept drift detection with quadtree-based spatial mapping of streaming data.
No full textOnline learning is a complex task, especially when the data stream changes its distribution over time. It’s challenging to monitor and detect these changes to maintain the performance of the learning algorithm. In this work, we present a novel detection method built from a different perspective of other preexisting detectors from literature. It analyzes the space occupied by the data, assuming that it would be immutable unless changes in this space occur among data of different classes. The data is mapped into a quadtree-based memory structure that provides knowledge about which class (label) is dominant in a given region of the feature space. Drifts are detected by checking whether data assigned to a given class occupy spaces considered relevant to the other class. The proposed method was evaluated on benchmark binary classification problems. The results show that our method can compete with well-known drift detectors from the literature on synthetic and real-world datasets
Collecting large volume data from wireless sensor network by drone.
No full textData collection is the most important task in wireless sensor networks (WSN). Each sensor node has to send
the sensed data to a special node called sink, which is the user interface. The sensor nodes far from the sink
send data to intermediate nodes that forward it by multi-hop data paths. This characteristic leads to higher
energy consumption in the sensor nodes close to the sink since they have to relay data from all other sensor
nodes. The literature presents several studies that use mobile sinks for data collection to reduce the number of
hops in the data paths and distributes the energy consumption, considering that the nodes close to the mobile
sink change. However, the majority of these studies consider only the network limitation, such as energy.
Furthermore, they also consider sensor nodes sending only one data packet to the mobile sink. This work
assumes a quad-copter drone as a mobile sink and sensor nodes having several data packets to send to the
sink. We propose two GRASP-based heuristics to define drone tours for data collection. Since this vehicle has
limited flight time, the primary metric analyzed here is the overall data collection time. Furthermore, they
guarantee that the mobile sink will stay a minimal time inside the radio range of each sensor node to ensure
that all of them will have enough time to send all data. The heuristics achieve this guarantee by looking for
a subset of locations, among the infinite points inside the monitored area, where the drone will hover for
data gathering. Hence, the proposed heuristics have to search for good locations to reduce the data gathering
time and define the shortest path to reduce the trip time. Simulated experiments showed that the proposed
GRASP-based heuristics outperformed the greed algorithm found as state of the art for this type of scenario,
mainly when the volume of data stored in each sensor node is high
Using police databases as a prospect to reduce under-recording of violence against women.
No full textObjetivo: buscou-se avaliar a concordância entre o Sistema de Informação de
Agravo de Notificação (SINAN) e dados policiais para casos de violência física e
sexual contra mulheres, bem como o perfil das mulheres agredidas, das agressões
e dos agressores. Método: foi realizado estudo transversal com casos ocorridos
em uma cidade de Minas Gerais, notificados no SINAN e/ou identificados na base
policial, entre os anos de 2015 e 2016. Criou-se uma base consolidada, composta
pelos casos elegíveis das duas fontes, tendo sido realizadas análises descritivas. Em
uma base pareada contendo casos comuns aos dois bancos, foi realizada análise de
concordância pelo teste Fleiss’Kappa. Resultados: 1.185 casos compuseram a base
consolidada e 56 constituíram a base pareada. Houve sub-registro de 83,54% nos
dados do SINAN, além de incompletude importante de informações. A base policial
apresentou cerca de oito vezes maior captação. A concordância de informações foi
elevada/moderada para sete de 11 características avaliadas para os casos comuns. Na
base consolidada, as vítimas foram predominantemente negras, solteiras ou viúvas,
com idade entre 18 e 39 anos. Os homens, especialmente (ex)parceiros e familiares,
foram os principais agressores. Conclusão: o sub-registro e a incompletude de
informações sobre violência contra mulher no SINAN é uma realidade que precisa
ser tratada. O cruzamento com fontes de dados policiais é uma alternativa para
melhorar a qualidade das informações, reduzindo o sub-registro. Apesar dos dados
subestimados, percebeu-se que a violência física e doméstica, cometida por (ex)
parceiro contra mulheres jovens e negras continua sendo prevalente, atentando para
o fato que se deve manter foco de políticas públicas.Objective: this study sought to evaluate the agreement between the Information
System for Notifiable Health Problems (Sistema de Informação de Agravo de
Notificação, SINAN) and Police data for cases of physical and sexual violence against
women, as well as the profile of the assaulted women, the aggressions and the
aggressors. Method: a cross-sectional study was conducted with cases in a city from
Minas Gerais, notified to the SINAN and/or identified in the Police database between
2015 and 2016. A consolidated database was created, comprised by the eligible cases
from both sources, with performance of descriptive analyses. An agreement analysis
by means of the Fleiss Kappa test was performed in a paired database containing
cases common to both databases. Results: a total of 1,185 cases comprised the
consolidated database, whereas 56 were included in the paired one. There was
83.54% under-recording in the SINAN data, in addition to important information
incompleteness. The Police database presented nearly eight times more recording
of cases. Agreement of all the information was high/moderate for seven out of 11
characteristics evaluated for the common cases. In the consolidated databases, the
victims were predominantly black-skinned, single or widowed, and aged between
18 and 39 years old. The main aggressors were men, mainly (former) partners
and family members. Conclusion: under-recording and incompleteness of diverse
information about violence against women in the SINAN is a reality that needs to
be dealt with. Cross-referencing with Police data sources represent an alternative
to improve quality of the information, reducing under-recording. Despite the
underestimated data, it was noticed that physical and domestic violence, perpetrated
by (former) partners against young and black-skinned women, continues to be
prevalent, pointing to the fact that it should remain as the focus of public policies
Longitudinal study of plasma visfatin/nicotinamide phosphoribosyltransferase (nampt) levels in healthy pregnant women.
No full textVisfatin/nicotinamide phosphorybosil transferase (NAMPT) is a novel adipocytokine with potential roles in the patho-
physiology of metabolic disorders, including gestational disorders. However, there is no clear interpretation regarding the
circulating visfatin levels in a healthy pregnancy. Therefore, we conducted the frst longitudinal study of plasma visfatin
levels that followed up healthy pregnant women until the third trimester, including the postpartum period (PPP). The study
recruited healthy women with singleton pregnancy who were not using any drug (including tobacco and alcohol). We have
excluded pregnant women who did not attend all scheduled exams and developed gestational diabetes or hypertension,
obesity, preeclampsia, or any infections during pregnancy. Nine women were considered eligible and examined during all
three trimesters of pregnancy and between 8 and 12 weeks postpartum (PPP). Visfatin/NAMPT concentrations were meas-
ured in EDTA-plasma by ELISA. The mean age of pregnant women included was 22±5 years (54% primiparous), and the
mean of gestational age at delivery was 40±1.2 weeks. Mean systolic and diastolic blood pressures were 90 and 70 mmHg,
respectively. Mean values (± standard error mean) of visfatin concentrations (μg/L) during trimesters were 11.38±1.45
(frst, 11–14 weeks), 9.18±1.82 (second, 20–24 weeks), 18.67±2.65 (third, 34–36 weeks), and 10.12±1.49 in the PPP. The
value of the third trimester was signifcantly higher than the second trimester, and signifcantly reduced in the PPP (p<0.05,
ANOVA with Bonferroni’s multiple comparison tests). Visfatin/NAMPT levels are signifcantly lower in the PPP, suggesting
that factors stimulating its production would be limited to pregnancy, thereby contributing to its potential application as a
biomarker in pregnancy complications
Coalitions of defense and tourism policies : the case of the Integrated Development Program of the Alcântara Space Center - MA.
No full textO estudo analisa as coalizões de defesa locais na agenda governamental do Programa de Desenvolvimento Integrado do Centro Espacial de Alcântara (PDI-CEA), no estado do Maranhão, com foco nas políticas públicas de turismo. Na metodologia empregada, utilizou a abordagem qualitativa, com levantamento bibliográfico e documental e entrevistas. Foram realizadas 14 entrevistas com os atores-chaves envolvidos na política pública de turismo em nível local. Os resultados apontaram que há credibilidade no Programa a ser executado pelo CEA, embora existam conflitos pertinentes, inclusive fundiários, que perpetuam até hoje e que diretamente interferem no desenvolvimento da atividade turística. Além disso, novas coalizões estão sendo formadas conforme previsto nas ações do PDI-CEA, a exemplo da Instância de Governança do Polo São Luís e Secretaria Municipal de Turismo de Alcântara.The objective is to analyze the local defense coalitions in the governmental agenda of the Integrated Development Program of the Alcântara Space Center (PDI-CEA), in the state of Maranhão, with a focus on public tourism policies. In the methodology used, a qualitative approach was used, with a bibliographic and documental survey and interviews. Fourteen interviews were conducted with key actors involved in public policy on tourism at the local level. The results pointed out that there is credibility in the Program to be executed by CEA, although there are pertinent conflicts, including land tenure, that perpetuate until today and that directly interfere in the development of tourist activity. In addition, new coalitions are being formed as foreseen in the actions of the PDI-CEA, such as the Governing Body of Polo São Luís and the Municipal Tourism Secretariat of Alcântara
Marcuse, Davis e as dimensões estéticas do feminismo.
No full textA perspectiva feminista de Angela Davis e Herbert Marcuse será aqui apresentada explorando três pontos que se encontram interligados: (1) as características consideradas especificamente femininas, (2) a desigualigualdade sexual na exploração do trabalho e (3) o potencial político radical do feminismo em movimentos de libertação. Para apresentar os dois primeiros pontos, utilizaremos textos de Herbert Marcuse; para o último, recorremos também a Angela Davis. Veremos, na sequência, como os dois teóricos críticos e ativistas mostram com clareza as transformações socioculturais ocorridas quando mulheres recorreram à dimensão estética – música, no nosso estudo de caso – como uma espécie de aliada capaz de fornecer uma trincheira mesmo nos tempos sombrios, como os de agora. Juntas, Davis e Marcuse podem despertar novas esperanças.Here, we would like to consider Angela Davis’ and Herbert Marcuse’s feminist perspectives exploring three points, which are interlaced: the so-called (1) specifically feminine characteristics, (2) the unequal sexual equality of exploitation, and (3) the radical political potential of feminism for liberation movements. For the first two points, we deal with Herbert Marcuse’s writings; for the last we turn to Angela Davis, as well. Both critical theorists and activists make it clear how social and cultural transformations have happened when women have appealed to the aesthetic dimension, music in our case study, as a sort of ally capable of providing a trench even in dark times – as they are now. Together, Marcuse and Davis can wake up new hopes
Saberes subjacentes ao percurso formativo e à praxis do professor de língua portuguesa : um estudo de caso.
No full textPrograma de Pós-Graduação em Letras. Departamento de Letras, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto.Este trabalho alinha-se às discussões acerca dos processos de formação docente, das atividades humanas e de suas relações com a linguagem. O objetivo é compreender os saberes que subjazem ao percurso formativo e à práxis do professor de Língua Portuguesa no período de Estágio Supervisionado. Para isso, constitui âncora teórica, principalmente, nos estudos de Bakhtin (1997), que concebe a linguagem como atividade interativa e sociocultural; de Tardif (2002) e Nóvoa (2017), que discutem os processos de formação docente; de Kleiman et al (2019, 2021) e Brasileiro e Pimenta (2021), que problematizam questões do letramento profissional do professor de Língua Portuguesa. Além disso, esta pesquisa considera os fundamentos da Linguística Aplicada (MOITA LOPES, 2006; RAJAGOPALAN, 2021), cujas pesquisas buscam, entre outros aspectos, situar o ser humano em seu contexto sociocultural. A metodologia da pesquisa constrói alicerce na abordagem qualitativa e, com finalidade explicativa, propõe a imersão no processo formativo de uma graduanda em Licenciatura em Língua Portuguesa, no período em que ela cumpre disciplinas de Estágio Supervisionado, com o objetivo de identificar os saberes subjacentes ao discurso e à prática dessa futura professora. Com inspiração nas metodologias da Clínica da Atividade (CLOT, 2007) e com o apoio de recursos múltiplos para geração de dados, tais como entrevista, observação sistemática do percurso, autoconfrontação e análise documental, foi construído material para um estudo de caso, o qual foi apresentado por via da narrativa. Todo esse processo se justifica pelo potencial de contribuir para a luta por políticas de valorização dos processos de formação de novos docentes e de experimentar uma práxis reflexiva e transformadora. Os resultados observados nesse percurso formativo evidenciaram que pensar a e na formação docente, dando relevo ao trabalhador em formação, no momento em que vivencia o Estágio Supervisionado, é algo complexo e revelador de saberes em constituição, que, ao mesmo tempo que parecem estar apropriados, mostram-se frágeis e instáveis. É, no momento em que o professor se depara com seu lócus de trabalho, a escola, e experimenta-se como profissional, que surgem dúvidas e oportunidades de ressignificá-las, em um espaço de interação, descobertas e aprendizagem que se constrói entre prática e teoria.This work is in line with discussions about teacher training processes, human activities and their relationship with language. The objective is to understand the knowledge that underlies the training path and the practice of the Portuguese Language teacher during the Supervised Internship period. For this, it constitutes a theoretical anchor, mainly, in the studies of Bakhtin (1997), who conceives language as an interactive and sociocultural activity; by Tardif (2002) and Nóvoa (2017), who discuss teacher training processes; by Kleiman et al (2019, 2021) and Brasileiro e Pimenta (2021), who problematize issues of professional literacy of Portuguese Language teachers. In addition, this research considers the foundations of Applied Linguistics (MOITA LOPES, 2006; RAJAGOPALAN, 2021), whose research seeks, among other aspects, to place human beings in their sociocultural context. The research methodology builds a foundation on the qualitative approach and, with an explanatory purpose, proposes the immersion in the formative process of a graduation student in Portuguese Language, in the period in which she fulfills disciplines of Supervised Internship, with the objective of identifying the knowledge underlying the discourse and practice of this future teacher. Inspired by the methodologies of Activity Clinic (CLOT, 2007) and with the support of multiple resources for data generation, such as interviews, systematic observation of the route, self-confrontation and document analysis, material was constructed for a case study, which was presented through the narrative. This whole process is justified by the potential to contribute to the fight for policies that value the training processes of new teachers and to experience a reflective and transformative praxis. The results observed in this training course showed that thinking about and in teacher training, highlighting the worker in training, when experiencing the Supervised Internship, is something complex and revealing of knowledge in the making, which, while appearing to be appropriate, appear fragile and unstable. It is, when the teacher is faced with his work locus, the school, and experiences himself as a professional, that doubts and opportunities arise to re-signify them, in a space of interaction, discoveries and learning that is built between practice and theory
A method for estimating paleotemperatures from pollen assemblages applied to the quantification of the Early Holocene warming in Central Brazil.
No full textThis study presents a method for the quantification of paleotemperatures from pollen records based on the predominant leaf margin trait of the genera represented in the pollen assemblages. The method presented here uses the well-known and widely used relationship between leaf margin and mean annual temperature, which is commonly applied to macrofloras to reconstruct paleotemperatures. Here, genera occurring in the arboreal vegetation of Central Brazil were analyzed respective to the presence or absence of species bearing toothed leaves. Using floristic surveys, a correlation between the proportion of genera without toothed species and the mean annual temperature was investigated. A positive linear correlation between these two variables was found for forest sites, but not for the arboreal savannas. The equation derived from the linear regression between the two variables - proportion of genera without toothed species and mean annual temperature (MAT) - was applied to pollen assemblages collected on forest sites. The equation was used to calculate estimated MATs for surface samples in order to test the validity of its application to pollen assemblages. The equation was then applied to fossil records to estimate paleoMATs for two Brazilian sites located respectively at 15.5◦ and 28◦ of latitude, during the Pleistocene-Holocene transition (between 13.6 and 10 kyr cal BP). While MAT increases of around 3 ◦C were found for the higher latitude site, no significant differences between final Pleistocene and early Holocene MATs were found for the near-equatorial site
Unsaturated polyester and its nanocomposites incorporated with graphene oxide - a brief review.
No full textIn the present review, the current status of the intrinsic mechanical, thermal and physical properties of bulk graphene oxide (GO) and chemically modified graphene oxide (mGO) unsaturated polyester nanocomposites
(UPNs) is thoroughly examined. The importance of Raman spectroscopy, X-Ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) in this review is clearly exhibited. Besides, the review to cover relevant knowledge about the UPNs and GO that are present in literature so far. Furthermore, the manufacture strategies of bulk graphene-based nanocomposites are discussed based on what has been reported in the literature. In addition, GO based UPNs have disclosed good performance related to mechanical properties and thermal stability and researchers have found optimal loadings that provide a novel material without agglomeration of the nanofillers. In particular, for the UPNs the presence of mGO at very low loadings can provide significant
reinforcement to the final material, in terms of mechanical and thermal stability. An outstanding attainment have been observed for a group of researchers in terms of electrical conductivity of UPN/mGO nanocomposites.
Finally, the potential applications and future perspectives are discussed with regard to scale up capabilities and possible developments for the novel material
Aglomerados espaciais de diabetes : características individuais e de vizinhança no estudo longitudinal ELSA-Brasil.
No full textThis study identified spatial clusters of type 2 diabetes mellitus among participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) residing in two cities and verified individual and neighborhood socioeconomic environmental characteristics associated with the spatial clusters. A cross-sectional study was conducted with 4,335 participants. Type 2 diabetes mellitus was defined as fasting blood glucose ≥ 126mg/dL (7.0mmol/L), oral glucose tolerance test ≥ 200mg/dL (11.1mmol/L), or glycated hemoglobin ≥6.5% (48mmol/L); by antidiabetic drug use; or by the self-reported medical diagnosis of type 2 diabetes mellitus. Neighborhood socioeconomic character istics were obtained from the 2011 Brazilian census. A spatial data analysis was conducted with the SaTScan method to detect spatial clusters. Logistic regression models were fitted to estimate the magnitude of associations. In total, 336 and 343 participants had type 2 diabetes mellitus in Belo Horizonte, Minas Gerais State (13.5%) and Salvador, Bahia State (18.5%), respectively. Two cluster areas showing a high chance of type 2 diabetes mellitus were identified in Belo Horizonte and Salvador. In both cities, participants living in the high type 2 diabetes mellitus cluster area were more likely to be mixed-race or black and have a low schooling level and manual work; these were also considered low-income areas. On the other hand, participants in the low type 2 diabetes mellitus cluster area of Salvador were less likely to be black and have low schooling level (university degree) and live in a low-income area. More vulnerable individual and neighborhood socioeconomic characteristics were associated with living in clusters of higher type 2 diabetes mellitus occurrence , whereas better contextual profiles were associated with clusters of lower prevalence