A Conceptual Image-Based Data Glove for Computer-Human Interaction

Data gloves are devices equipped with sensors that capture the movements of the hand of the user in order to select or manipulate objects in a virtual world. Data gloves were introduced three decades ago and since then have been used in many 3D interaction techniques. However, good data gloves are too expensive and only a few of them can perceive the full set of hand movements. In this paper we describe the design of an image-based data glove (IBDG) prototype suitable for finger sensible applications, like virtual objects manipulation and interaction approaches. The proposed device uses a camera to track visual markers at finger tips, and a software module tocompute the position of each finger tip and its joints in real-time. To evaluate our concept, we have built a prototype and tested it with 15 volunteers. We also discuss how to improve the engineering of the prototype, how to turn it into a low cost interaction device, as well as other relevant issues about this original concept

Automatic subject-based contextualisation of programming assignment lists.

As programming must be learned by doing, introductory programming course learners need to solve many problems, e.g., on systems such as ’Online Judges’. However, as such courses are often compulsory for non-Computer Science (nonCS) undergraduates, this may cause difficulties to learners that do not have the typical intrinsic motivation for programming as CS students do. In this sense, contextualised assignment lists, with programming problems related to the students’ major, could enhance engagement in the learning process. Thus, students would solve programming problems related to their academic context, improving their comprehension of the applicability and importance of programming. Nonetheless, preparing these contextually personalised programming assignments for classes for different courses is really laborious and would increase considerably the instructors’/monitors’ workload. Thus, this work aims, for the first time, to the best of our knowledge, to automatically classify the programming assignments in Online Judges based on students’ academic contexts by proposing a new context taxonomy, as well as a comprehensive pipeline evaluation methodology of cutting edge competitive Natural Language Processing (NLP). Our comprehensive methodology pipeline allows for comparing state of the art data augmentation, classifiers, beside NLP approaches. The context taxonomy created contains 23 subject matters related to the non-CS majors, representing thus a challenging multi-classification problem. We show how even on this problem, our comprehensive pipeline evaluation methodology allows us to achieve an accuracy of 95.2%, which makes it possible to automatically create contextually personalised program assignments for non-CS with a minimal error rate (4.8%)

Influência de rotações de culturas nas propriedades físico-hídricas de um Latossolo Vermelho em plantio direto.

A adoção do plantio direto, com a inclusão de espécies gramíneas de relação C/N alta, poderá minimizar a degradação estrutural do solo. O objetivo deste trabalho foi avaliar a influência da inclusão da braquiária na rotação de culturas nas propriedades físico-hídricas e no conteúdo de matéria orgânica de um Latossolo Vermelho distrófico em plantio direto. O delineamento experimental foi o de blocos ao acaso, em parcelas subdivididas, com quatro repetições. As parcelas foram compostas por quatro sistemas de rotação, e as subparcelas, por quatro profundidades de amostragem (0-10; 10-20; 20-40, e 40-60 cm). As culturas utilizadas foram: arroz (A); feijão irrigado (F); milho (M); soja (S), e arroz (A+B), milho (M+B) e soja (S+B) consorciados com braquiária. Os sistemas de rotação foram: S1 - A/F/M/F/S/F; S2 - A+B/F/M+B/F/S+B/F; S3 - M/F/S/F/S/F, e S4 - M+B/F/S+B/F/S+B/F. Uma área de mata nativa, situada a 500 m do experimento, foi considerada como controle. A inclusão da braquiária na rotação de culturas não afetou a densidade, a macroporosidade e a capacidade de água disponível do solo. A porosidade total e o teor de matéria orgânica do solo foram favorecidos pelas rotações que incluíam maior número de cultivos de soja. A associação de soja com a braquiária contribuiu para a estabilidade dos agregados, e a de gramíneas de verão com a braquiária, para a diminuição da resistência do solo à penetração

Gone With the Water: The Loss of Genetic Variability in Black and Gold Howler Monkeys (Alouatta caraya) Due to Dam Construction

Black and gold howler monkeys (Alouatta caraya) inhabit several eco-regions in South America with the highest population densities in riverine forests. Dam construction for electricity production represents a severe human alteration of ecosystems with consequences for primate conservation. To evaluate the possible loss of genetic diversity in A. caraya, we analysed and compared the genetic structure of the species across 22 study sites in Argentina (14), Paraguay (1), and Brazil (7). Four of these study sites (referred to as flooded) were sampled before dam-linked flooding which most likely caused a drastic decline or functional extinction of these populations. The genetic variability of 256 individuals was evaluated using 10 autosomal microsatellites (STRs) and 112 individuals by sequencing a fragment of 507 bp of mtDNA. DNA was extracted from tissue, blood, and faecal samples. Significantly higher values of genetic variability were observed for the flooded populations both in mtDNA and STRs. Population genetic structure showed a K = 1, 2, or 5 depending on the method, separating Argentinian and Paraguayan sites from Brazilian sites and, in the case of K = 5, two clusters were mostly represented by flooded populations. Isolation-by-distance analyses showed that geographic distances influence gene flow. Analytical methods, such as Pairwise Fst’s and Nei’s and regression model of Harpending and Ward, were concordant in detecting significant genetic structuring between flooded and remaining sites examined. Although some sites have very low sample sizes, these samples are of great importance since these sampling sites are currently flooded. Our results show that the study sites where dams were built had the greatest genetic diversity. As A. caraya is currently severely threatened by yellow fever outbreaks, the remaining populations may be more vulnerable to disease outbreaks due to impoverished genetic variability. Accordingly, it is essential to implement management actions to conserve the remaining populations. Our results underline the importance for Environmental Impact Assessments (EIA) to include data on the genetic structure of species in the affected sites prior to their alteration or destruction. These genetic data are also remarkably important for determining where to relocate specific individuals to help avoid biodiversity loss.Fil: Oklander, Luciana Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Caputo, Mariela. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Fernández, Gabriela Paula. Universidad Nacional del Noroeste de la Provincia de Buenos Aires. Centro de Bioinvestigaciones (Sede Pergamino); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires. Universidad Nacional del Noroeste de la Provincia de Buenos Aires. Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires; ArgentinaFil: Jerusalinsky, Leandro. Centro Nacional de Pesquisa e Conservação de Primatas Brazileiros; BrasilFil: de Oliveira, Silviene F.. Universidade do Brasília; BrasilFil: Bonatto, Sandro Luis. Pontificia Universidade Católica do Rio Grande do Sul; BrasilFil: Corach, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentin

Environmental evaluation and nano-mineralogical study of fresh and unsaturated weathered coal fly ashes

Coal combustion and the disposal of combustion wastes emit enormous quantities of nano-sized particles that pose significant health concerns on exposure, particularly in unindustrialized countries. Samples of fresh and weathered class F fly ash were analysed through various techniques including X-ray fluorescence (XRF), X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), field-emission gun scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM) coupled with energy dispersive x-ray spectroscopy (EDS), and Raman Spectroscopy. The imaging techniques showed that the fresh and weathered coal fly ash nanoparticles (CFA-NPs) are mostly spherical shaped. The crystalline phases detected were quartz, mullite, ettringite, calcite, maghemite, hematite, gypsum, magnetite, clay residues, and sulphides. The most abundant crystalline phases were quartz mixed with Al-Fe-Si-K-Ti-O-amorphous phases whereas mullite was detected in several amorphous phases of Al, Fe, Ca, Si, O, K, Mg, Mn, and P. The analyses revealed that CFANPs are 5–500 nm in diameter and encapsulate several potentially hazardous elements (PHEs). The carbon species were detected as 5–50 nm carbon nanoballs of graphitic layers and massive fullerenes. Lastly, the aspects of health risks related to exposure to some detected ambient nanoparticles are also discussed

Simultaneous production of mesoporous biochar and palmitic acid by pyrolysis of brewing industry wastes

Pyrolysis of malt bagasse was carried out to obtain simultaneously a mesoporous biochar and an oil fraction rich in palmitic acid. The best result for biochar production was at 500 °C with holding time of 10 min. The yields of biochar and pyrolytic oil in this condition were, 29.7 and 33.9 wt%, respectively. The pyrolysis temperature and holding time influenced the yields of the products. An increase in pyrolysis temperature (from 500 to 700 °C) and holding time (from 10 to 50 min) caused a decrease in biochar yield, a reduction in the volatile matter content and an increase in the amount of ash. Additionally, in the range studied in this work, the increase of the pyrolysis temperature caused a decrease in the specific surface area and total pore volume of the biochar. Meanwhile, the biochar presented interesting functional groups and a mesoporous character, which can be a precursor to obtain adsorbents, or even, be used as adsorbent. The pyrolytic oil was composed of oxygenated aromatic compounds, the main fraction being palmitic acid (27.3%), which can be used in a number of applications, including biodiesel production. This work demonstrated that an available and problematic waste, malt bagasse, can be converted simultaneously into a mesoporous biochar and, into a pyrolytic oil rich in palmitic acid. Biochar and pyrolytic oil, in turn, are products of great value and can be applied in several fields

Abnormal sensory integration affects balance control in hemiparetic patients within the first year after stroke

OBJECTIVE: Impairments in balance can be a consequence of changes in the motor, sensory, and integrative aspects of motor control. Abnormal sensory reweighting, i.e., the ability to select the most appropriate sensory information to achieve postural stability, may contribute to balance impairment. The Sensory Organization Test is a component of Computerized Dynamic Posturography that evaluates the impact of visual, vestibular, and somatosensory inputs, as well as sensory reweighting, under conditions of sensory conflict. The aim of this study is to compare balance control in hemiparetic patients during the first year post-stroke and in age-matched neurologically normal subjects using the Berg Balance Scale and Computerized Dynamic Posturography. METHODS: We compared the Berg Balance Scale and Sensory Organization Test scores in 21 patients with hemiparesis after first-ever ischemic stroke and in 21 age-matched, neurologically normal subjects. An equilibrium score was defined for each Sensory Organization Test condition. RESULTS: Berg Balance Scale scores were significantly lower in the patients than in the neurologically normal subjects. Equilibrium scores were significantly lower in the patients than in the neurologically normal subjects for those Sensory Organization Test conditions that did not provide appropriate somatosensory information and under conditions of sensory conflict. A history of falls was more frequent in patients with lower equilibrium scores. CONCLUSION: During the first year after a stroke, defective sensory reweighting significantly impacts balance control in hemiparetic patients. These results are important for the planning of effective rehabilitation interventions