A new CPG model for the generation of modular trajectories for hexapod robots

Legged robots are often used in a large variety of tasks, in different environments. Nevertheless, due to the large number of degrees-of-freedom to be controlled, online generation of trajectories in these robots is very complex. In this paper, we consider a modular approach to online generation of trajectories, based on biological concepts, namely Central Pattern Generators (CPGs). We introduce a new CPG model for hexapod robots’ rhythms, based in the work of Golubitsky et al (1998). Each neuron/oscillator in the CPG consists of two modules/primitives: rhythmic and discrete. We study the effect on the robots’ gaits of superimposing the two motor primitives, considering two distinct types of coupling.We conclude, from the simulation results, that the amplitude and frequency of periodic solutions, identified with hexapods’ tripod and metachronal gaits, remain constant for the two couplings, after insertion of the discrete part.CP was supported by Research funded by the European Regional Development Fund through the programme COMPETE and by the Portuguese Government through the FCT Fundacao para a Ciencia e a Tecnologia under the project PEst-C/MAT/UI0144/2011. This work was also funded by FEDER Funding supported by the Operational Program Competitive Factors COMPETE and National Funding supported by the FCT - Portuguese Science Foundation through project PTDC/EEACRO/100655/2008

Impact of discrete corrections in a modular approach for trajectory generation in quadruped robots

Online generation of trajectories in robots is a very complex task that involves the combination of different types of movements, i.e., distinct motor primitives. The later are used to model complex behaviors in robots, such as locomotion in irregular terrain and obstacle avoidance. In this paper, we consider two motor primitives: rhythmic and discrete. We study the effect on the robots’ gaits of superimposing the two motor primitives, considering two distinct types of coupling. Additionally, we simulate two scenarios, where the discrete primitive is inserted in all of the four limbs, or is inserted in ipsilateral pairs of limbs. Numerical results show that amplitude and frequency of the periodic solutions, corresponding to the gaits trot and pace, are almost constant for diffusive and synaptic couplings.CP was supported by Research funded by the European Regional Development Fund through the programme COMPETE and by the Portuguese Government through the FCT Fundacao para a Ciencia e a Tecnologia under the project PEst-C/MAT/UI0144/2011. This work was also funded by FEDER Funding supported by the Operational Program Competitive Factors COMPETE and National Funding supported by the FCT - Portuguese Science Foundation through project PTDC/EEACRO/100655/2008

A modular approach for trajectory generation in biped robots

Robot locomotion has been a major research issue in the last decades. In particular, humanoid robotics has had a major breakthrough. The motivation for this study is that bipedal locomotion is superior to wheeled approaches on real terrain and situations where robots accompany or replace humans. Some examples are, on the development of human assisting device, such as prosthetics, orthotics, and devices for rehabilitation, rescue of wounded troops, help at the office, help as maidens, accompany and assist elderly people, amongst others. Generating trajectories online for these robots is a hard process, that includes different types of movements, i.e., distinct motor primitives. In this paper, we consider two motor primitives: rhythmic and discrete.We study the effect on a bipeds robots’ gaits of inserting the discrete part as an offset of the rhythmic primitive, in synaptic and diffusive couplings. Numerical results show that amplitude and frequency of the periodic solution, corresponding to the gait run are almost constant in all cases studied here.(undefined

Heat treatment and wounding as abiotic stresses to enhance the bioactive composition of pineapple by-products

Abiotic stress, like heat treatment and wounding, applied to pineapple by-products induce the accumulation of new compounds and add value. In this work the effect of the individual or combined application of wounding and heat treatment stresses on total phenolic content, antioxidant activity through complementary methods (DPPH, FRAP, and ABTS) and enzymatic activity (bromelain, phenylalanine ammonia lyase (PAL) and polyphenol oxidase) were evaluated. Whole and wounded pineapple shell and core were dipped in a hot water bath at 30 ± 1 °C or 40 ± 1 °C for 10 min and stored under refrigeration conditions (4 ± 1 °C) for 24 h or 48 h. Results allowed that pineapple by-products reacted differently to the tested stresses. For the core, the application of wounding and heat treatment (40 °C) before storage (24 h) induced a synergistic effect on the accumulation of phenols (increased 17%) and antioxidant activity (422%). For the shell samples, the treatment that most increased the content of phenols (14%) and antioxidant activity (3845%) was heat treatment at 30 °C and storage for 48 h. Treatments that positively influenced the content of phenols and antioxidant activity of the samples did not affect the activity of bromelain or PAL. This study showed that proper abiotic stresses could increase the functional value of by-products.The first author acknowledges the financial support from Fundação para a Ciência e a Tecnologia (FCT), Portugal, through Doctoral fellowship (SFRH/BD/109124/2015). This work was supported by the national funding of FCT, under the scope of the strategic funding to the research units LEAF, Linking Landscape, Environment, Agriculture, and Food, School of Agriculture, University of Lisbon, 1349-017 Lisbon (UIDP/04129/2020), Associate Laboratory LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro (UIDB/50006/2020) and CEB, Centre of Biological Engineering, Department of Biological Engineering, University of Minho, 4710–057 Braga (UIDP/04469/2020) through national funds and where applicable co-financed by the FEDER, within the PT2020 Partnership Agreement.info:eu-repo/semantics/publishedVersio

a systematic review in children and adolescents aged 6-18 years

© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.OBJECTIVE: This report aimed to systematically review the evidence for a differential association between objective and self-reported physical activity and cardiorespiratory fitness on academic achievement. DESIGN: Systematic review. DATA SOURCES: Studies were identified from searches in Embase, Education Resources Information Center, PubMed, PsycINFO, SPORTdiscus and Web of Science databases from January 2000 to December 2016. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Eligibility criteria included cross-sectional, longitudinal and interventional study designs. Outcomes included students' school grade or a standardised test or measure of academic achievement. Explanatory variables were cardiorespiratory fitness and objective and self-reported physical activity. Inclusion criteria included school-aged children and adolescents aged-18 years (or students from primary to secondary school when student's participants age was not described) and articles published in English, Portuguese or Spanish. RESULTS: A total of 51 articles met inclusion criteria: 41 cross-sectional, 2 intervention and 8 longitudinal studies. Results from 11 studies were inconsistent regarding the relationship between objectively measured physical activity and academic achievement. Ten of the 16 articles reported positive associations between self-reported physical activity and academic achievement. From the 22 studies that analysed the relationship between cardiorespiratory fitness and academic achievement, it was verified that they all generally support the beneficial effect of cardiorespiratory fitness on students' academic achievement. CONCLUSION: Higher cardiorespiratory fitness may be important to enhance children and adolescents' health and, additionally, academic achievement. Due to a lack of consensus across studies, methodological issues associated with the assessment of physical activity should be considered when investigating physical activity and academic achievement.publishe

CCAAT/Enhancer binding protein β induces motility and invasion of glioblastoma cells through transcriptional regulation of the calcium binding protein S100A4

This work is licensed under a Creative Commons Attribution 3.0 License.We have previously shown that decreased expression of CCAAT/Enhancer binding protein β (C/EBPβ) inhibits the growth of glioblastoma cells and diminishes their transformation capacity and migration. In agreement with this, we showed that C/ EBPβ depletion decreases the mRNA levels of different genes involved in metastasis and invasion. Among these, we found S100 calcium binding protein A4 (S100A4) to be almost undetectable in glioblastoma cells deficient in C/EBPβ. Here, we have evaluated the possible role of S100A4 in the observed effects of C/EBPβ in glioblastoma cells and the mechanism through which S100A4 levels are controlled by C/EBPβ. Our results show that C/EBPβ suppression significantly reduced the levels of S100A4 in murine GL261 and human T98G glioblastoma cells. By employing an S100A4-promoter reporter, we observed a significant induction in the transcriptional activation of the S100A4 gene by C/EBPβ. Furthermore, overexpression of S100A4 in C/EBPβ- depleted glioblastoma cells reverses the enhanced migration and motility induced by this transcription factor. Our data also point to a role of S100A4 in glioblastoma cell invasion and suggest that the C/EBPβ gene controls the invasive potential of GL261 and T98G cells through direct regulation of S100A4. Finally, this study indicates a role of C/EBPβ on the maintenance of the stem cell population present in GL261 glioblastoma cells.This work was supported by MINECO (SAF2010–16365) and by Fundación Mutua Madrileña (to A.P.-C.). CIBERNED is funded by the Instituto de Salud Carlos III. D.A.-M. is a fellow of the MINECO.Peer Reviewe

Insights into the accessory genome of two pseudomonas aeruginosa clinical isolates using comparative genomics

Recently, we have set a collaboration with Hospital de Braga, located in the North of Portugal, that handles over 600 P. aeruginosa isolates per year, aiming to rouse a holistic research approach to provide relevant information and tools to the clinicians to circumvent the multi-resistance phenomena in P. aeruginosa. Since then, we have set procedures aiming a systematic phenotypic characterization of the clinical isolates and developed strategies for the identification of pathogenicity islands and SNPs among the clinical isolates via comparative genomics. In this context, we have determined the full genome sequence of two clinical isolates using the high-throughput system Illumina Genome Analyzer IIx. These two clinical isolates, named 138244 and 152504, are representatives of allelic sequence types ST175 (widely disseminated and associated with multidrug-resistance) and ST560 (rare allele), respectively. Importantly, under standardized experimental procedures, isolate 138244 did not produce pigments and evidenced an antibiotic pan-resistant phenotype whereas 152504 produced a high amount of pyocyanin pigment and was susceptible to all antibiotics tested. A comparative genomic analysis using the genome sequences of both isolates and of all P. aeruginosa strains deposited in Genbank so far, allowed the identification of the accessory genome content of both isolates. Apparently, isolate 152504 harbors in its genome 254 unique genes, often clustered together in the same locus. Based on the genome annotation information, the pool of unique genes mainly encode several virulence factors, chemical stress resistance systems as well as 183 hypothetical proteins, 45 of which predicted members of the secretome of P. aeruginosa 152504. The accessory genome of 138244 mainly includes genes associated with mobile elements (phages, transposases, integrons) and genes encoding for 160 hypothetical proteins. Currently, research approaches are focused on the functional elucidation of sets of genes encoding hypothetical proteins of both isolates and in the description and characterization of their secretomes.Fundação para a Ciência e a Tecnologia (FCT

Comparative genomics of two pseudomonas aeruginosa clinical isolates to elucidate the composition of their mobilomes

Recently, we have set a collaboration with Hospital de Braga, located in the North of Portugal, that handles over 600 P. aeruginosa isolates per year, aiming to rouse a holistic research approach to provide relevant information and tools to the clinicians to circumvent the multi-resistance phenomena in P. aeruginosa. Since then, we have set procedures aiming a systematic phenotypic characterization of the clinical isolates and developed strategies for the identification of pathogenicity islands and SNPs among the clinical isolates via comparative genomics. In this context, we have determined the full genome sequence of two clinical isolates using the high-throughput system Illumina Genome Analyzer IIx. These two clinical isolates, named 138244 and 152504, are representatives of allelic sequence types ST175 (widely disseminated and associated with multidrug-resistance) and ST560 (rare allele), respectively. Importantly, under standardized experimental procedures, isolate 138244 did not produce pigments and evidenced an antibiotic pan-resistant phenotype whereas 152504 produced a high amount of pyocyanin pigment and was susceptible to all antibiotics tested. A comparative genomic analysis using the genome sequences of both isolates and of all P. aeruginosa strains deposited in Genbank so far, allowed the identification of the accessory genome content of both isolates. Apparently, isolate 152504 harbors in its genome 243 unique genes, often clustered together in the same locus. Based on the genome annotation information, the pool of unique genes mainly encode several virulence factors, chemical stress resistance systems as well as 106 hypothetical proteins, some of which predicted members of the secretome of P. aeruginosa 152504. The accessory genome of 138244 mainly includes genes associated with mobile elements (phages, transposases, integrons) and genes encoding for 190 hypothetical proteins. Currently, research approaches are focused on the functional elucidation of sets of genes encoding hypothetical proteins of both isolates and in the description and characterization of their secretomes.Fundação para a Ciência e a Tecnologia (FCT

Optimization of the effect of pineapple by-products enhanced in bromelain by hydrostatic pressure on the texture and overall quality of silverside beef cut

Dehydrated pineapple by-products enriched in bromelain using a hydrostatic pressure treatment (225 MPa, 8.5 min) were added in marinades to improve beef properties. The steaks from the silverside cut (2 ± 0.5 cm thickness and weight 270 ± 50 g), characterized as harder and cheaper, were immersed in marinades that were added to dehydrated and pressurized pineapple by-products that corresponded to a bromelain concentration of 0–20 mg tyrosine, 100 g−1 meat, and 0–24 h time, according to the central composite factorial design matrix. Samples were characterized in terms of marination yield, pH, color, and histology. Subsequently, samples were cooked in a water-bath (80 °C, 15 min), stabilized (4 °C, 24 h), and measured for cooking loss, pH, color, hardness, and histology. Marinades (12–24 h) and bromelain concentration (10–20 mg tyrosine.100 g−1 meat) reduced pH and hardness, increased marination yield, and resulted in a lighter color. Although refrigeration was not an optimal temperature for bromelain activity, meat hardness decreased (41%). Thus, the use of pineapple by-products in brine allowed for the valorization of lower commercial value steak cuts.The first author acknowledges the financial support from Fundação para a Ciência e a Tecnologia (FCT),Portugal, through a doctoral fellowship (SFRH/BD/109124/2015). This work was supported by the national fundingof FCT, under the scope of the strategic funding to the research units LEAF, Linking Landscape, Environment,Agriculture and Food, School of Agriculture, University of Lisbon, 1349-017 Lisbon (UIDP/04129/2020), CIISA,Interdisciplinary Centre of Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon,1300-477, Lisbon (UIDB/00276/2020) FMV and PDR2020-1.0.1-FEADER-031359, funded by the European RegionalDevelopment Fund (ERDF)), QOPNA (UID/QUI/00062/2019), LAQV-REQUIMTE, Department of Chemistry,University of Aveiro, 3810-193 Aveiro (UIDB/50006/2020) and CEB, Centre of Biological Engineering, Departmentof Biological Engineering, University of Minho, 4710–057 Braga (UIDP/04469/2019) through national funds andwhere applicable co-financed by the FEDER, within the PT2020 Partnership Agreement.info:eu-repo/semantics/publishedVersio

Promoting health-related cardiorespiratory fitness in physical education : the role of class intensity and habitual physical activity

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Physical education (PE) has the potential to promote health-related fitness, however, its contribution is still not clear. The aim of this study was to assess whether students' health-related cardiorespiratory fitness (CRF) improved from the beginning to the end of the school year, and to examine the role of PE class intensity and habitual physical activity (PA) in promoting students' CRF. This observational study employed a longitudinal design. Participants were 212 7th and 8th grade students (105 boys), mean age 12.9 years old, followed during one school year, from September 2017 to June 2018. The Progressive Aerobic Cardiovascular Endurance Run (PACER) was used to assess CRF at baseline and follow-up. PA was measured using accelerometers. PE class intensity was assessed using the System for Observing Fitness Instruction Time. Findings indicated that from the beginning to the end of the school year, a greater percentage of participants were in the CRF healthy fitness zone (73.1% to 79.7%, p = 0.022). Among boys, participating in organized sports (B = 4.61, 95% confidence interval [CI]: 0.33, 8.88) and the percentage of PE time being very active (B = 0.90, 95% CI: 0.44, 1.35) were positively associated with the change in PACER laps. Among girls, daily vigorous PA (B = 0.38, 95% CI: 0.15, 0.60) and participating in organized sports (B = 4.10, 95% CI: 0.93, 7.27) were also positively associated with PACER change, while being overweight or obese (B = -5.11, 95% CI: -8.28, -1.93) was negatively associated. In conclusion, PE was demonstrated to have a positive role in the promotion of CRF, especially among boys, while for girls, habitual PA seems to have a greater contribution. Nevertheless, results and conclusions should be considered carefully, taking into account study limitations, such as the non-direct measures of PE class intensity, CRF, and school setting.M.P. is supported by Fundação para a Ciência e a Tecnologia (FCT), grant number SFRH/BD/122219/2016. CIPER is financed by Fundação para a Ciência e a Tecnologia (FCT) within the unit I&D 472, grant number UID/DTP/00447/2019.info:eu-repo/semantics/publishedVersio