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Improving trend analysis using social network features
No full textAbstract\ud
In recent years, large volumes of data have been massively studied by researchers and organizations. In this context, trend analysis is one of the most important areas. Typically, good prediction results are hard to obtain because of unknown variables that could explain the behaviors of the subject of the problem. This paper goes beyond standard trend identification methods that consider only historical behavior of the objects by including the structure of the information sources, i.e., social network metrics, as an additional dimension to model and predict trends over time. Results from a set of experiments indicate that including such metrics has improved the prediction accuracy. Our experiments considered the publication titles, as recorded in the Brazilian Lattes database, from all the Ph.Ds. in Computer Science registered in the Brazilian Lattes platform for the periods analyzed in order to evaluate the proposed trend prediction approach.This work was partially funded by FAPESP, CAPES, and CNPq
Combined effect of pulse density and grid cell size on predicting and mapping aboveground carbon in fast-growing Eucalyptus forest plantation using airborne LiDAR data
No full textAbstract
Background
LiDAR remote sensing is a rapidly evolving technology for quantifying a variety of forest attributes, including aboveground carbon (AGC). Pulse density influences the acquisition cost of LiDAR, and grid cell size influences AGC prediction using plot-based methods; however, little work has evaluated the effects of LiDAR pulse density and cell size for predicting and mapping AGC in fast-growing Eucalyptus forest plantations. The aim of this study was to evaluate the effect of LiDAR pulse density and grid cell size on AGC prediction accuracy at plot and stand-levels using airborne LiDAR and field data. We used the Random Forest (RF) machine learning algorithm to model AGC using LiDAR-derived metrics from LiDAR collections of 5 and 10 pulses m−2 (RF5 and RF10) and grid cell sizes of 5, 10, 15 and 20 m.
Results
The results show that LiDAR pulse density of 5 pulses m−2 provides metrics with similar prediction accuracy for AGC as when using a dataset with 10 pulses m−2 in these fast-growing plantations. Relative root mean square errors (RMSEs) for the RF5 and RF10 were 6.14 and 6.01%, respectively. Equivalence tests showed that the predicted AGC from the training and validation models were equivalent to the observed AGC measurements. The grid cell sizes for mapping ranging from 5 to 20 also did not significantly affect the prediction accuracy of AGC at stand level in this system.
Conclusion
LiDAR measurements can be used to predict and map AGC across variable-age Eucalyptus plantations with adequate levels of precision and accuracy using 5 pulses m−2 and a grid cell size of 5 m. The promising results for AGC modeling in this study will allow for greater confidence in comparing AGC estimates with varying LiDAR sampling densities for Eucalyptus plantations and assist in decision making towards more cost effective and efficient forest inventory
A validation study of the Multidimensional Life Satisfaction Scale for Children
No full textAbstract\ud
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Introduction\ud
Recent studies on the life satisfaction in children and young people have investigated its association with vulnerability, discrimination, the individual’s school environment and network of relationships, and mental health. The growing interest in the area demands instruments with good psychometric properties.\ud
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Aim\ud
The aim of this study is to study the psychometric properties of the Multidimensional Life Satisfaction Scale for Children (MLSS-C).\ud
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Method\ud
The participants were 379 elementary schoolchildren aged 9 to 14 (M = 10.5 years), enrolled in public schools in a city in the state of São Paulo, Brazil. The instruments used were the MLSS-C, the Self-Description Assessment Questionnaire 1 (SDQ1), the Social Skills Rating System (SSRS), and the Childhood Stress Scale (CSS). Two data collections were made, one in the fifth year of elementary school and one in the sixth. Confirmatory factor analysis (CFA) was carried out to assess the structural model’s goodness of fit. The internal consistency (Cronbach’s alpha and composite reliability), test-retest reliability and the discriminant, convergent, and divergent validity were also assessed.\ud
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Results\ud
Regarding CFA, after removing items with saturation values below .50, six dimensions proposed by the authors remained, five of them with alpha values above .70. The construct validity was confirmed by finding moderate and positive correlations between life satisfaction and self-concept and social skills (convergent validity) and lower and negative correlation with childhood stress (divergent validity).\ud
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Conclusion\ud
Together, the reported results provide preliminary evidence of the reliability and validity of this scale. It is suggested, therefore, that this scale is suitable for both research and practice with Brazilian schoolchildren.This study was funded by Coordination for the Improvement of Higher\ud
Education Personnel (CAPES) attributed to Cynthia Cassoni
New insights from Gorongosa National Park and Niassa National Reserve of Mozambique increasing the genetic diversity of Trypanosoma vivax and Trypanosoma vivax-like in tsetse flies, wild ungulates and livestock from East Africa
No full textAbstract\ud
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Background\ud
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Trypanosoma (Duttonella) vivax is a major pathogen of livestock in Africa and South America (SA), and genetic studies limited to small sampling suggest greater diversity in East Africa (EA) compared to both West Africa (WA) and SA.\ud
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Methods\ud
Multidimensional scaling and phylogenetic analyses of 112 sequences of the glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) gene and 263 sequences of the internal transcribed spacer of rDNA (ITS rDNA) were performed to compare trypanosomes from tsetse flies from Gorongosa National Park and Niassa National Reserve of Mozambique (MZ), wild ungulates and livestock from EA, and livestock isolates from WA and SA.\ud
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Results\ud
Multidimensional scaling (MDS) supported Tvv (T. vivax) and TvL (T. vivax-like) evolutionary lineages: 1) Tvv comprises two main groups, TvvA/B (all SA and WA isolates plus some isolates from EA) and TvvC/D (exclusively from EA). The network revealed five ITS-genotypes within Tvv: Tvv1 (WA/EA isolates), Tvv2 (SA) and Tvv3–5 (EA). EA genotypes of Tvv ranged from highly related to largely different from WA/SA genotypes. 2) TvL comprises two gGAPDH-groups formed exclusively by EA sequences, TvLA (Tanzania/Kenya) and TvLB-D (MZ). This lineage contains more than 11 ITS-genotypes, seven forming the lineage TvL-Gorongosa that diverged from T. vivax Y486 enough to be identified as another species of the subgenus Duttonella. While gGAPDH sequences were fundamental for classification at the subgenus, major evolutionary lineages and species levels, ITS rDNA sequences permitted identification of known and novel genotypes.\ud
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Conclusions\ud
Our results corroborate a remarkable diversity of Duttonella trypanosomes in EA, especially in wildlife conservation areas, compared to the moderate diversity in WA. Surveys in wilderness areas in WA may reveal greater diversity. Biogeographical and phylogenetic data point to EA as the place of origin, diversification and spread of Duttonella trypanosomes across Africa, providing relevant insights towards the understanding of T. vivax evolutionary history.Grants were awarded to MMGT and EPC from CNPq (PROAFRICA), CAPES\ud
(PNIPB) and FAPESP (Process 2016/07487–0) Brazilian agencies to support\ud
this research. CMFR was a postdoctoral fellowship from CAPES (PNIPB) and\ud
is currently supported by CNPq, ACR received postdoctoral fellowships from\ud
CAPES (PNPD and PNIPB), and HAG has been supported by fellowships from\ud
CNPq and FAPESP (Process 2016/03028–1)
Airway and parenchyma immune cells in influenza A(H1N1)pdm09 viral and non-viral diffuse alveolar damage
No full textAbstract\ud
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Background\ud
Diffuse alveolar damage (DAD), which is the histological surrogate for acute respiratory distress syndrome (ARDS), has a multifactorial aetiology. Therefore it is possible that the immunopathology differs among the various presentations of DAD. The aim of this study is to compare lung immunopathology of viral (influenza A(H1N1)pdm09) to non-viral, extrapulmonary aetiologies in autopsy cases with DAD.\ud
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Methods\ud
The lung tissue of 44 patients, was divided in the H1N1 group (n = 15) characterized by severe pulmonary injury due to influenza A(H1N1)pdm09 infection; the ARDS group (n = 13), characterized by patients with DAD due to non-pulmonary causes; and the Control group (n = 16), consisting of patients with non-pulmonary causes of death. Immunohistochemistry and image analysis were used to quantify, in the parenchyma and small airways, several immune cell markers.\ud
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Results\ud
Both DAD groups had higher expression of neutrophils and macrophages in parenchyma and small airways. However, there was a higher expression of CD4+ and CD8+ T lymphocytes, CD83+ dendritic cells, granzyme A+ and natural killer + cell density in the lung parenchyma of the H1N1 group (p < 0.05). In the small airways, there was a lower cell density of tryptase + mast cells and dendritic + cells and an increase of IL-17 in both DAD groups (p < 0.05).\ud
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Conclusion\ud
DAD due to viral A(H1N1)pdm09 is associated with a cytotoxic inflammatory phenotype, with partially divergent responses in the parenchyma relative to the small airways. In non-viral DAD, main immune cell alterations were found at the small airway level, reinforcing the role of the small airways in the pathogenesis of the exudative phase of DAD.This work was funded by the Brazilian Research Council (CNPq)
Force level of small diameter nickel-titanium orthodontic wires ligated with different methods
No full textAbstract\ud
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Background\ud
The aim of this study was to compare the deflection force in conventional and thermally activated nickel-titanium (NiTi) wires in passive (Damon Q) and active (Bioquick) self-ligating brackets (SLB) and in conventional brackets (CB) tied by two different methods: elastomeric ligature (EL) and metal ligature (ML).\ud
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Methods\ud
Two wire diameters (0.014 and 0.016 in.) and 10 specimens per group were used. The specimens were assembled in a clinical simulation device and tested in an Instron Universal Testing Machine, with a load cell of 10 N. For the testing procedures, the acrylic block representative of the right maxillary central incisor was palatally moved, with readings of the force at 0.5, 1, 2, and 3 mm, at a constant speed of 2 mm/min and temperature of 36.5 °C.\ud
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Results\ud
The conventional NiTi released higher forces than the thermally activated NiTi archwires in large deflections. In general, the SLB showed lower forces, while the ML had higher forces, with both showing a similar force release behavior, constantly decreasing as the deflection decreased. The EL showed an irregular behavior. The active SLB showed smaller forces than passive, in large deflections.\ud
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Conclusions\ud
The SLB and the ML exhibit standard force patterns during unloading, while the elastomeric ligatures exhibit a randomly distributed force release behavior
Zika virus congenital syndrome: experimental models and clinical aspects
No full textAbstract\ud
Viral infections have long been the cause of severe diseases to humans, increasing morbidity and mortality rates worldwide, either in rich or poor countries. Yellow fever virus, H1N1 virus, HIV, dengue virus, hepatitis B and C are well known threats to human health, being responsible for many million deaths annually, associated to a huge economic and social cost. In this context, a recently introduced flavivirus in South America, called Zika virus (ZIKV), led the WHO to declare in February 1st 2016 a warning on Public Health Emergency of International Concern (PHEIC). ZIKV is an arbovirus of the Flaviviridae family firstly isolated from sentinels Rhesus sp. monkeys at the Ziika forest in Uganda, Africa, in 1947. Lately, the virus has well adapted to the worldwide spread Aedes aegypti mosquito, the vector for DENV, CHIKV, YFV and many others. At first, it was not considered a threat to human health, but everything changed when a skyrocketing number of babies born with microcephaly and adults with Guillain-Barré syndrome were reported, mainly in northeastern Brazil. It is now well established that the virus is responsible for the so called congenital Zika syndrome (CZS), whose most dramatic features are microcephaly, arthrogryposis and ocular damage. Thus, in this review, we provide a brief discussion of these main clinical aspects of the CZS, correlating them with the experimental animal models described so far.This work was supported by FAPESP process no. 2011/18703–2
Targeted metatranscriptomics of compost-derived consortia reveals a GH11 exerting an unusual exo-1,4-β-xylanase activity
No full textAbstract\ud
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Background\ud
Using globally abundant crop residues as a carbon source for energy generation and renewable chemicals production stand out as a promising solution to reduce current dependency on fossil fuels. In nature, such as in compost habitats, microbial communities efficiently degrade the available plant biomass using a diverse set of synergistic enzymes. However, deconstruction of lignocellulose remains a challenge for industry due to recalcitrant nature of the substrate and the inefficiency of the enzyme systems available, making the economic production of lignocellulosic biofuels difficult. Metatranscriptomic studies of microbial communities can unveil the metabolic functions employed by lignocellulolytic consortia and identify novel biocatalysts that could improve industrial lignocellulose conversion.\ud
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Results\ud
In this study, a microbial community from compost was grown in minimal medium with sugarcane bagasse sugarcane bagasse as the sole carbon source. Solid-state nuclear magnetic resonance was used to monitor lignocellulose degradation; analysis of metatranscriptomic data led to the selection and functional characterization of several target genes, revealing the first glycoside hydrolase from Carbohydrate Active Enzyme family 11 with exo-1,4-β-xylanase activity. The xylanase crystal structure was resolved at 1.76 Å revealing the structural basis of exo-xylanase activity. Supplementation of a commercial cellulolytic enzyme cocktail with the xylanase showed improvement in Avicel hydrolysis in the presence of inhibitory xylooligomers.\ud
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Conclusions\ud
This study demonstrated that composting microbiomes continue to be an excellent source of biotechnologically important enzymes by unveiling the diversity of enzymes involved in in situ lignocellulose degradation.This work was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (Grants 10/52362-5 and 15/13684-0 to Igor Polikarpov and 11/21608-1 to Bruno L. Mello) and the Biotechnology and Biological Sciences Research Council (BB/I018492/1 to Neil C. Bruce and Simon McQueen-Mason). The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication
Enhanced rates of enzymatic saccharification and catalytic synthesis of biofuel substrates in gelatinized cellulose generated by trifluoroacetic acid
No full textAbstract\ud
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Background\ud
The crystallinity of cellulose is a principal factor limiting the efficient hydrolysis of biomass to fermentable sugars or direct catalytic conversion to biofuel components. We evaluated the impact of TFA-induced gelatinization of crystalline cellulose on enhancement of enzymatic digestion and catalytic conversion to biofuel substrates.\ud
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Results\ud
Low-temperature swelling of cotton linter cellulose in TFA at subzero temperatures followed by gentle heating to 55 °C dissolves the microfibril structure and forms composites of crystalline and amorphous gels upon addition of ethanol. The extent of gelatinization of crystalline cellulose was determined by reduction of birefringence in darkfield microscopy, loss of X-ray diffractability, and loss of resistance to acid hydrolysis. Upon freeze-drying, an additional degree of crystallinity returned as mostly cellulose II. Both enzymatic digestion with a commercial cellulase cocktail and maleic acid/AlCl3-catalyzed conversion to 5-hydroxymethylfurfural and levulinic acid were markedly enhanced with the low-temperature swollen cellulose. Only small improvements in rates and extent of hydrolysis and catalytic conversion were achieved upon heating to fully dissolve cellulose.\ud
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Conclusions\ud
Low-temperature swelling of cellulose in TFA substantially reduces recalcitrance of crystalline cellulose to both enzymatic digestion and catalytic conversion. In a closed system to prevent loss of fluorohydrocarbons, the relative ease of recovery and regeneration of TFA by distillation makes it a potentially useful agent in large-scale deconstruction of biomass, not only for enzymatic depolymerization but also for enhancing rates of catalytic conversion to biofuel components and useful bio-products.This material is based upon work supported as part of the Center for Direct\ud
Catalytic Conversion of Biomass to Biofuels (C3Bio), an Energy Frontier\ud
Research Center funded by the U.S. Department of Energy, Ofce of Science,\ud
Ofce of Basic Energy Sciences, and Award Number DE-SC0000997.\ud
TMS work at Purdue University was supported in part by Coordenação\ud
para a Pesquisa de Nível Superior—CAPES, for the fnancial support (Process\ud
BEX-10734/13-9)