Study of age-related changes in postural control during quiet standing through Linear Discriminant Analysis

<p>Abstract</p> <p>Background</p> <p>The human body adopts a number of strategies to maintain an upright position. The analysis of the human balance allows for the understanding and identification of such strategies. The displacement of the centre of pressure (COP) is a measure that has been successfully employed in studies regarding the postural control. Most of these investigations are related to the analysis of individuals suffering from neuromuscular disorders. Recent studies have shown that the elderly population is growing very fast in many countries all over the world, and therefore, researches that try to understand changes in this group are required. In this context, this study proposes the analysis of the postural control, measured by the displacement of the COP, in groups of young and elderly adults.</p> <p>Methods</p> <p>In total 59 subjects participated of this study. They were divided into seven groups according to their age. The displacement of the COP was collected for each subject standing on a force plate. Two experimental conditions, of 30 seconds each, were investigated: opened eyes and closed eyes. Traditional and recent digital signal processing tools were employed for feature computation from the displacement of the COP. Statistical analyses were carried out in order to identify significant differences between the features computed from the distinct groups that could allow for their discrimination.</p> <p>Results</p> <p>Our results showed that Linear Discrimination Analysis (LDA), which is one of the most popular feature extraction and classifier design techniques, could be successfully employed as a linear transformation, based on the linear combination of standard features for COP analysis, capable of estimating a unique feature, so-called <it>LDA-value</it>, from which it was possible to discriminate the investigated groups and show a high correlation between this feature and age.</p> <p>Conclusion</p> <p>These results show that the analysis of features computed from the displacement of the COP are of great importance in studies trying to understand the ageing process. In particular, the <it>LDA-value </it>showed to be an adequate feature for assessment of changes in the postural control which can be related to functional changes that occur over the ageing.</p

Evapotranspiration from a Mediterranean evergreen oak savannah: The role of trees and pasture

Mediterranean evergreen oak woodlands of southern Portugal (montados) are savannah-type ecosystems with a widely sparse tree cover, over extensive grassland. Therefore, ecosystem water fluxes derive from two quite differentiated sources: the trees and the pasture. Partitioning of fluxes according to these different sources is necessary to quantify overall ecosystem water losses as well as to improve knowledge on its functional behaviour. In southern Iberia, these woodlands are subjected to recurrent droughts. Therefore, reaction/resilience to water stress becomes an essential feature of vegetation on these ecosystems. Long-term tree transpiration was recorded for 6 years from a sample of holm oak (Quercus ilex ssp. rotundifolia) trees, using the Granier sap flow method. Ecosystem transpiration was measured by the eddy covariance technique for an 11-month period (February to December 2005), partly coincident with a drought year. Pasture transpiration was estimated as the difference between ecosystem (eddy covariance) and tree (sap flow) transpiration. Pasture transpiration stopped during the summer, when the surface soil dried up. In the other seasons, pasture transpiration showed a strong dependence on rainfall occurrence and on top soil water. Conversely, trees were able to maintain transpiration throughout the summer due to the deep root access to groundwater. Q. ilex trees showed a high resilience to both seasonal and annual drought. Tree transpiration represented more than half of ecosystem transpiration, in spite of the low tree density (30 trees ha 1) and crown cover fraction (21%). Tree evapotranspiration was dominated by transpiration (76%), and interception loss represented only 24% of overall tree evaporatio

Modelling of smart irrigation with replan and redistribution algorithms

It is a priority develop intelligent irrigation systems to save water. Using optimal control formulations and techniques, the water consumption can be made to follow more closely the hydrological needs of the crop, taking into account current weather conditions. Here, the mathematical model presented by the authors in previous publications is improved. This new model incorporates new features like the slope of the soil, the possibility to include a percentage of water losses due to runoff, and a percentage of water losses if the soil is on the field capacity. A new and efficient replan strategy is applied tacking into account the data measured from moisture sensors, to ensure that hydric needs of the crop is fulfilled. A new approach to deal with multiple irrigation points is also proposed. It allows to redistribute the available water in the case an irrigation point is not able to provide the water needed.FEDER/COMPETE/NORTE2020/POCI/FCT funds through grants [UID/EEA/-00147/20 13/UID/IEEA/00147/ 006933-SYSTEC], project, To CHAIR – [POCI-01-0145-FEDER028247] and [UPWIND - POCI-FEDER-FCT -31447]. This work was also supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding [UID/FIS/04650/2019], [UIDB/00013/2020] and [UIDP/00013/2020 of CMAT-UM]

O Ensino do empreendedorismo como factor distintivo das instituições de ensino superior

Atas das I Jornadas Ensino do Empreendedorismo em Portugal, Coimbra, Portugal, 8 de abril 2015.As práticas de empreendedorismo são hoje entendidas como parte da missão das Instituições de Ensino Superior, face às suas características intrínsecas e ao papel preponderante que têm no incentivo e apoio aos empreendedores. Neste contexto, o presente estudo pretendeu conhecer a forma e importância que as diversas Instituições de Ensino Superior Politécnico (IESP) em Portugal, atribuem ao ensino e práticas de Empreendedorismo. Para atingir tal objectivo, elaborou-se um “Indicador de Performance Empreendedora das IESP (IPEIESP), visando hierarquizar as práticas das organizações, em três dimensões diferentes: Participação em Projectos de Empreendedorismo; Leccionação de disciplinas de Empreendedorismo integradas nos seus cursos; Fomento de práticas de empreendedorismo. Do estudo empírico realizado, que consistiu na análise da informação disponibilizada nas páginas da Internet de cada Instituição nacional de Ensino Superior Politécnico (IESP), no que se refere às suas práticas de Empreendedorismo. A análise da Performance Empreendedora revelou uma maior relação entre o número de projectos em que a Instituição participa, bem como a actividade proactiva de fomento de Empreendedorismo, do que com a leccionação de Unidades Curriculares neste âmbito. Na sequência desta primeira abordagem, irão ser dirigidos questionários às IESP, no sentido de se confirmar, ou não, a leitura que o Ranking agora obtido nos permite obter

In Vitro Hepatotoxic and Neurotoxic Effects of Titanium and Cerium Dioxide Nanoparticles, Arsenic and Mercury Co-Exposure

This article belongs to the Special Issue Toxicity of Nanomaterials and Legacy Contaminants: Risks to the Environment and Human Health.Considering the increasing emergence of new contaminants, such as nanomaterials, mixing with legacy contaminants, including metal(loid)s, it becomes imperative to understand the toxic profile resulting from these interactions. This work aimed at assessing and comparing the individual and combined hepatotoxic and neurotoxic potential of titanium dioxide nanoparticles (TiO2NPs 0.75-75 mg/L), cerium oxide nanoparticles (CeO2NPs 0.075-10 μg/L), arsenic (As 0.01-2.5 mg/L), and mercury (Hg 0.5-100 mg/L) on human hepatoma (HepG2) and neuroblastoma (SH-SY5Y) cells. Viability was assessed through WST-1 (24 h) and clonogenic (7 days) assays and it was affected in a dose-, time- and cell-dependent manner. Higher concentrations caused greater toxicity, while prolonged exposure caused inhibition of cell proliferation, even at low concentrations, for both cell lines. Cell cycle progression, explored by flow cytometry 24 h post-exposure, revealed that TiO2NPs, As and Hg but not CeO2NPs, changed the profiles of SH-SY5Y and HepG2 cells in a dose-dependent manner, and that the cell cycle was, overall, more affected by exposure to mixtures. Exposure to binary mixtures revealed either potentiation or antagonistic effects depending on the composition, cell type and time of exposure. These findings prove that joint toxicity of contaminants cannot be disregarded and must be further explored.This research was funded by FEDER—Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), and by Portuguese funds through FCT—Fundação para a Ciência e a Tecnologia in the framework of the project POCI-01-0145-FEDER-029651. This work was also financed by national funds through FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of projects UIDB/04750/2020 and LA/P/0064/2020. This work was also developed within the scope of the project CICECO- Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC). A.T. Reis thanks the financial support of FCT through individual Grant SFRH/BPD/122112/2016. C.B. Lopes and A.C. Estrada acknowledge their research position funded by national funds (OE), through FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19.info:eu-repo/semantics/publishedVersio

Novel and classic myoepithelial/stem cell markers in metaplastic carcinomas of the breast

Metaplastic carcinomas of the breast (MCBs) are unusual neoplasms characterized by an admixture of glandular epithelial components, which frequently exhibit features of squamous differentiation, and mesenchymal malignant components. Regardless of the presence of myoepithelial features in MCB, no consensus concerning their putative histogenesis has yet been achieved. Recently, novel putative myoepithelial markers have been developed, including p63, maspin, and P-cadherin. We assessed the expression of these myoepithelial markers in MCBs and compared their expression with classic myoepithelial markers. Immunohistochemistry using the streptavidin– biotin–peroxidase complex technique with antibodies raised against p63, maspin, P-cadherin, actin (clones CGA7, 1A4 and HHF35), cytokeratin 14 (Ck14), and vimentin was performed on 16 MCBs (7 matrix-producing MCBs, 6 adenosquamous MCBs, and 3 MCBs with heterologous elements). In healthy breast lobules and ducts adjacent to the tumors, myoepithelial cells showed distinctive and consistent immunoreactivity for p63, maspin, P-cadherin, actin, S-100 protein, and Ck14. Matrix- producing MCBs were positive for maspin in all cases, for p63 in 4 of 7 cases, and for P-cadherin in 4 of 7 cases. Adenosquamous MCB showed immunoreactivity for p63, maspin, and P-cadherin in 5 of 6 cases. All novel myoepithelial markers and Ck14 decorated squamous cell islands. MCBs with heterologous elements were positive for p63 in 1 case, for maspin in all 3 cases, and for P-cadherin in 2 cases. All cases showed at least one of the novel myoepithelial markers. Eleven of 16 cases were positive for actin. Eleven of 14 cases reacted with Ck14, and all cases that stained for S-100 protein (9 of 9) and vimentin (13 of 13) were also positive. Based on our findings, the balance of probabilities favors that MCBs may have a basal or myoepithelial cell histogenesis and differentiation.Fundacão para a Ciência e a Tecnologia (FCT), Ministério da Ciência e Tecnologia (MCT) - SFRH/BD/5386/2001

Lexical, morphological and syntactic development in toddlers between 16 and 30 months old: a comparison across European Portuguese and Galician

The main aims of this study were to investigate the relationship between the lexical size and the emergence of morphological and syntactic markers in toddlers between the ages of 16 and 30 months and to compare these results between Galician and European Portuguese. Parents of 3012 Portuguese toddlers and those of 1081 Galician toddlers completed the MacArthur–Bates Communicative Development Inventory: Words and Sentences. The results indicated that the number of words, the ability to combine words and the number of different morphemes produced increased with age. The ability to combine words was used as an indicator of syntactic development; this ability was also associated with the toddlers’ lexical size. In both samples, gender morphemes seemed to be the first to have their production generalized, followed by the plural and the past participle. The production of gender morphemes was accompanied by a small lexical size, whereas the imperfect tense and the person mark onset were associated with large lexical sizes. The implications of these results for charting the continuity between lexical, morphological and syntactical development are discussed.CiPsi - Psychology Research Centre, Uminho (UID/PSI/ 01662/2013), Portugal. National Funds through the FCT (Foundation for Science and Technology) and co-financed by European Regional Development Funds (FEDER) through the the National Strategic Reference Framework (QREN) - FCOMP- 01-0124-FEDER-029556 and through the Competitiveness and Internationalization Operational Program (POCI) with the references and POCI-01-0145-FEDER-007562CIEC – Research Centre on Child Studies, IE, UMinho (FCT R&D unit 317), Portugal. BPD/102549/2014info:eu-repo/semantics/publishedVersio

Degradation of paracetamol by wet peroxide oxidation using carbon nanotubes synthesized from plastic solid waste

Within increased production and economic/social dependence of plastic utilization, an environmental problem has also emerged. In this scenario, plastic solid waste (PSW) recycling/management/recovery has become a problem of public concern, with a global generation estimated at 150 million tonnes per year. Materials produced from PSW can be classified as primary (performance/characteristics equivalent to virgin plastic), secondary (performance’s requirement lower than the original application), tertiary (PSW used as feedstock for the generation of chemicals and fuels), and quaternary (energy recovery via incineration) recycled materials [1]. For instance, pyrolysis of PSW has been extensively used for the thermochemical conversion of useless PSW into oil, gas, and carbon materials, thus classified as terciary recycled material.Adriano S. Silva thanks his doctoral Grant with reference SFRH/BD/151346/2021 financed by the Portuguese Foundation for Science and Technology (FCT), with funds from NORTE2020, under MIT Portugal Program. This work was financially supported by UIDB/05757/2020 (CeDRI), UIDB/00690/2020 (CIMO), LA/P/0045/2020 (ALiCE), UIDB/50020/2020, UI-DP/50020/2020 (LSRE-LCM) and funded by national funds through FCT/MCTES (PIDDAC). Fernanda F. Roman acknowledges the national funding by FCT through the individual research grant SFRH/BD/143224/2019info:eu-repo/semantics/publishedVersio