Nitrogen (N) has commonly been applied in Eucalyptus stands in Brazil and it has a direct relation with biomass production and chlorophyll content. Foliar N concentrations are used to diagnose soil and plant fertility levels and to develop N fertilizer application rates. Normally, foliar N is obtained using destructive methods, but indirect analyses using Vegetation Indexes (VIs) may be possible. The aim of this work was to evaluate VIs to estimate foliar N concentration in three Eucalyptus clones. Lower crown leaves of three clonal Eucalyptus plantations (25 months old) were classified into five color patterns using the Munsell Plant Tissue Color Chart. ).

Estimation of the presence of people in real time is extremely useful for businesses in providing better services while saving money. In this paper, we propose a technique for estimating the number of mobile devices present at a certain place and time, through analysis of WiFi probe requests from smart devices. Our goal is to address the problem through a solution that is immune to Media Access Control (MAC) address randomization strategies. The idea is to make use of information propagated in the environment, without the need to know the real MAC addresses of the devices. A state machine was modeled to detect the arrival, presence, and departure of devices in proximity to the sensors. A hardware prototype was developed for device detection, and its efficiency was evaluated in experiments that involved comparing the results of the proposed method with the manual measurements made by researchers. The proposed method provided very accurate correlations between the number of mobile devices detected and the real number of people in the environment.

RESUMOO gênero Hymenaea pertence à família Leguminosae, subfamília Caesalpinoideae, com nome popular de jatobá. No gênero Hymenaea, foram descritas aproximadamente 25 espécies. Já no Brasil, verifica-se a presença de 13 espécies, com destaque para a Hymenaea martiana Hayne e a Hymenaea courbaril Linneaus. Na literatura, há vários trabalhos que tratam principalmente da quebra de dormência das sementes e da produção de mudas, sobretudo da espécie Hymenaea courbaril Linneaus, porém essas avaliações por matriz ainda são incipientes. Este trabalho teve por objetivo avaliar e comparar a germinação e o crescimento inicial de mudas entre as espécies e as matrizes de Hymenaea martiana Hayne e Hymenaea courbaril Linneaus. Foram desenvolvidos dois experimentos: o primeiro avaliou a germinação, e o segundo, o crescimento inicial de mudas. As duas espécies avaliadas apresentaram comportamentos distintos entre a germinação e o crescimento inicial das mudas, sendo a Hymenaea courbaril Linneaus a espécie com maior média para ambas variáveis, porém não apresentou variabilidade fenotípica entre matrizes.Palavras-chave: jatobá, variabilidade fenotípica, produção de mudas. Germination and Seedling Growth Among Matrices of Two Species of the Genus Hymenaea ABSTRACTThe Hymenaea genus belongs to the family Leguminosae, subfamily Caesalpinoideae with the common name jatobá. Approximately 25 species have been described in the genus Hymenaea and 13 of them are present in Brazil. Among them we can highlight the species Hymenaea martiana Hayne and Hymenaea courbaril Linneaus. In literature, there are several studies dealing mainly the dormancy breakage and the seedling production, mainly with Hymenaea coubaril Linneaus, but these reviews per matrices are incipient. This study aimed to evaluate and compare the germination and seedling growth between species and between matrices of the Hymenaea martiana Hayne and Hymenaea courbaril Linneaus. Two experiments were conducted: the first evaluated the germination and the second the seedlings growth. The two species studied showed different behavior between germination and the seedling growth, with Hymenaea courbaril Linneaus showing the greatest average for both variables. However, this did not show phenotypic variability between matrices.

The paradigm of the Internet of everything (IoE) is advancing toward enriching people’s lives by adding value to the Internet of things (IoT), with connections among people, processes, data, and things. This paper provides a survey of the literature on IoE research, highlighting concerns in terms of intelligence services and knowledge creation. The significant contributions of this study are as follows: (1) a systematic literature review of IoE taxonomies (including IoT); (2) development of a taxonomy to guide the identification of critical knowledge in IoE applications, an in-depth classification of IoE enablers (sensors and actuators); (3) validation of the defined taxonomy with 50 IoE applications; and (4) identification of issues and challenges in existing IoE applications (using the defined taxonomy) with regard to insights about knowledge processes. To the best of our knowledge, and taking into consideration the 76 other taxonomies compared, this present work represents the most comprehensive taxonomy that provides the orchestration of intelligence in network connections concerning knowledge processes, type of IoE enablers, observation characteristics, and technological capabilities in IoE applications.

Leaf hyperspectral reflectance has been used to estimate nutrient concentrations in plants in narrow bands of the electromagnetic spectrum. The aim of this study was to estimate leaf nutrient concentrations using leaf hyperspectral reflectance and verify the variable selection methods using the partial least squares regression (PLSR). Two studies were carried out using stands with Eucalyptus clones. Study I was established in Eucalyptus stands with three clones, classifying leaves into five colour patterns using the Munsell chart for plant tissues. Immediately after leaf collection, leaf reflectance was read and the chemical analysis was performed. Study II was carried out in commercial clonal stands of Eucalyptus performing the same leaf sampling and chemical analysis as used in Study I. All leaf reflectance spectra were smoothed and three more pre-processing procedures were applied. In addition, three methods of PLSR were tested. The first derivative was more accurate for predicting nitrogen (R cv 2 = 0.95), phosphorous (R cv 2 = 0.93), and sulphur concentration (R cv 2 = 0.85). The estimates for concentrations of calcium (R cv 2 = 0.81), magnesium (R cv 2 = 0.22), and potassium (R cv 2 = 0.76) were more accurate using the logarithm transformation. Only the estimates for iron concentrations were performed with higher accuracy (R cv 2 = 0.35) using the smoothed reflectance. The copper concentrations were more accurate (R cv 2 = 0.78) using the logarithm transformation. Concentrations of boron (R cv 2 = 0.68) and manganese (R cv 2 = 0.79) were more accurate using the first derivative, while zinc (R cv 2 = 0.31) concentration was most accurate using the second derivative.

A contaminação de solos por mercúrio é um problema ambiental grave, com potencial de biomagnificação em cadeias alimentares e danos à saúde humana. O objetivo do presente trabalho foi avaliar o efeito de diferentes concentrações de HgO na germinação e desenvolvimento de plântulas de Sapindus saponária submetidas a escarificação mecânica. O experimento foi instalado em DIC com quatro repetições de 25 sementes, no esquema fatorial 4 x 2, sendo estudado o efeito de quatro concentrações de HgO em vermiculita (C1 – 0,000 g/cm3;.C2 – 0,025 g/cm3; C3 – 0,050 g/cm3 e C4 – 0,075 g/cm3) e de dois pré-tratamentos (P1 – Testemunha: sementes com tegumento intacto e P2 – escarificação mecânica do tegumento em esmeril elétrico). Avaliaram-se atributos relacionados à germinação e desenvolvimento de plântulas. Realizaram-se teste F, análise de regressão e teste t pareado, todos a 5,0 % de significância estatística. A escarificação mecânica do tegumento com esmeril elétrico favoreceu a embebição das sementes (100,0 %), germinação (85,25 %) e emissões de raízes laterais (70,0 %) e de parte aérea (76,25 %). A presença de mercúrio na vermiculita prejudicou o desenvolvimento das plântulas. Conclui-se que a escarificação mecânica do tegumento com esmeril elétrico pode ser indicado para superar a dormência das sementes de S. saponaria. Esta espécie tolera pequenas concentrações de HgO (0,0045 g/cm3) sem causar maiores danos ao seu crescimento e acúmulo de massa verde.

The learning experience in virtual environments can be significantly improved through the effective introduction of collaborative learning. The group formation of students is a crucial aspect in a such learning. Due to the lack of interaction between students, this task becomes complex, requiring automatic and intelligent tools to help students, tutors and environments to determine groupings for collaborative work. This article is a joint effort of two research groups, aimed at fostering the advancement of collaborative learning, presenting the use of personality traits of the Big Five model, identified through natural language texts produced by students. The experiments performed independently were compared, demonstrating the feasibility of the proposals.Resumo. A experiência de aprendizagem em ambientes virtuais pode ser significativamente melhorada através da introdução efetiva de aprendizagem colaborativa. A formação de gruposé um aspecto crucial para este tipo de aprendizagem. Devidoà ausência de interação entre estudantes, esta tarefa torna-se complexa, sendo necessárias ferramentas para auxiliar a determinar agrupamentos para trabalho colaborativo. Este artigoé um esforço conjunto de dois grupos de pesquisa, visando promover o avanço da aprendizagem colaborativa, utilizando o modelo Big Five de personalidade, identificados nos textos produzidos pelos alunos. Os experimentos realizados independentemente foram comparados, demonstrando a viabilidade das propostas.

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