1,261 research outputs found
Atlas versus range maps: robustness of chorological relationships to distribution data types in European mammals
Aim Chorological relationships describe the patterns of distributional overlap
among species. In addition to revealing biogeographical structure, the resulting
clusters of species with similar geographical distributions can serve as natural
units in conservation planning. Here, we assess the extent to which temporal,
methodological and taxonomical differences in the source of species’ distribution
data can affect the relationships that are found
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
Nanomaterials of Carbon and Metal Sulfides in Photocatalysis
Heterogeneous semiconductor photocatalysis has received much interest because of its applications in important global energy and environmental challenges in a cost-effective sustainable way. The photocatalytic efficiency of semiconductor photocatalysts under solar irradiation has been pointed out by difficulties associated with low visible-light absorption range, fast recombination of photogenerated carriers, and low chemical stability in operational conditions. Graphitic materials have attracted great interest due to properties, such as high surface area, mechanical strength, and photochemical stability. Thus, their combination with metal sulfides, has been explored as promising strategies to produce new photocatalysts. These nanocomposites show great potential in photodegradation of contaminants of emerging concern (CEC), which might be detected in water sources, such as traces of Pharmaceutics and pesticides. Here, we briefly review fundamental principles photocatalysis in general, with the focus on the use of carbon-nanomaterials of distinct structural dimensionalities associated with nanocrystalline metal sulfides, envisaging their application as heterogeneous photocatalysts for water remediation. Key aspects concerning the photocatalyst properties, such as light absorption, charge separation and transfer, and stability, are also approached. Graphene and graphene derivatives have demonstrated great potential for increasing photogenerated charge-carrier separation and migration efficiency, as well as in extending the light absorption range and adsorption capacity
Octodon degus: A Model for the Cognitive Impairment Associated with Alzheimer's Disease
Octodon degus (O. degus) is a diurnal rodent that spontaneously develops several physiopathological conditions, analogous in many cases to those experienced by humans. In light of this, O. degus has recently been identified as a very valuable animal model for research in several medical fields, especially those concerned with neurodegenerative diseases in which risk is associated with ageing. O. degus spontaneously develops β-amyloid deposits analogous to those observed in some cases of Alzheimer’s disease (AD). Moreover, these deposits are thought to be the key feature for AD diagnosis, and one of the suggested causes of cell loss and cognitive deficit. This review aims to bring together information to support O. degus as a valuable model for the study of cerebral aging
Colloidal nanomaterials for water quality improvement and monitoring
Water is the most important resource for all kind forms of live. It is a vital resource distributed unequally across different regions of the globe, with populations already living with water scarcity, a situation that is spreading due to the impact of climate change. The reversal of this tendency and the mitigation of its disastrous consequences is a global challenge posed to Humanity, with the scientific community assuming a major obligation for providing solutions based on scientific knowledge. This article reviews literature concerning the development of nanomaterials for water purification technologies, including collaborative scientific research carried out in our laboratory (nanoLAB@UA) framed by the general activities carried out at the CICECO-Aveiro Institute of Materials. Our research carried out in this specific context has been mainly focused on the synthesis and surface chemical modification of nanomaterials, typically of a colloidal nature, as well as on the evaluation of the relevant properties that arise from the envisaged applications of the materials. As such, the research reviewed here has been guided along three thematic lines: 1) magnetic nanosorbents for water treatment technologies, namely by using biocomposites and graphite-like nanoplatelets; 2) nanocomposites for photocatalysis (e.g., TiO2/Fe3O4 and POM supported graphene oxide photocatalysts; photoactive membranes) and 3) nanostructured substrates for contaminant detection using surface enhanced Raman scattering (SERS), namely polymers loaded with Ag/Au colloids and magneto-plasmonic nanostructures. This research is motivated by the firm believe that these nanomaterials have potential for contributing to the solution of environmental problems and, conversely, will not be part of the problem. Therefore, assessment of the impact of nanoengineered materials on eco-systems is important and research in this area has also been developed by collaborative projects involving experts in nanotoxicity. The above topics are reviewed here by presenting a brief conceptual framework together with illustrative case studies, in some cases with original research results, mainly focusing on the chemistry of the nanomaterials investigated for target applications. Finally, near-future developments in this research area are put in perspective, forecasting realistic solutions for the application of colloidal nanoparticles in water cleaning technologies.publishe
Variable outcomes of human heart attack recapitulated in genetically diverse mice.
Clinical variation in patient responses to myocardial infarction (MI) has been difficult to model in laboratory animals. To assess the genetic basis of variation in outcomes after heart attack, we characterized responses to acute MI in the Collaborative Cross (CC), a multi-parental panel of genetically diverse mouse strains. Striking differences in post-MI functional, morphological, and myocardial scar features were detected across 32 CC founder and recombinant inbred strains. Transcriptomic analyses revealed a plausible link between increased intrinsic cardiac oxidative phosphorylation levels and MI-induced heart failure. The emergence of significant quantitative trait loci for several post-MI traits indicates that utilizing CC strains is a valid approach for gene network discovery in cardiovascular disease, enabling more accurate clinical risk assessment and prediction
Multifunctional silver-coated transparent TiO2 thin films for photocatalytic and antimicrobial applications
Transparent TiO2 thin films coated with Ag NPs were synthesized using two industrially applicable techniques,
pulsed laser ablation (PLAL) and spray pyrolysis without using high vacuum. These transparent thin films were
deposited on glass in order to generate glass materials with photocatalytic and antimicrobial properties and a
minimum loss of transparency. The structural, morphological and optical properties of the thin films were
examined using Grazing incidence X-ray diffraction (GIXRD), Raman spectroscopy, Scanning electron microscopy (SEM) and ultraviolet–visible spectroscopy. Transmission electron microscopy (TEM) was used to identify
the NPs on the TiO2 surface. The transmittance value for the thin films was greater than 80%.The thin films thus
synthesized were then assessed to determine their photocatalytic capacity by monitoring the degradation of
Rhodamine B (RhB) under UV light irradiation. Ag NPs on the TiO2 surface ensures an improvement in the
photocatalytic properties, with a 99% degradation of RhB in 210 min under UV light. In addition, these transparent thin films showed high antimicrobial activity on Gram-negative bacteria when irradiated by UV light for
4 h, killing 93% of these bacteria.Funding for open access charge: CRUE-Universitat Jaume
Variable outcomes of human heart attack recapitulated in genetically diverse mice
Clinical variation in patient responses to myocardial infarction (MI) has been difficult to model in laboratory animals. To assess the genetic basis of variation in outcomes after heart attack, we characterized responses to acute MI in the Collaborative Cross (CC), a multi-parental panel of genetically diverse mouse strains. Striking differences in post-MI functional, morphological, and myocardial scar features were detected across 32 CC founder and recombinant inbred strains. Transcriptomic analyses revealed a plausible link between increased intrinsic cardiac oxidative phosphorylation levels and MI-induced heart failure. The emergence of significant quantitative trait loci for several post-MI traits indicates that utilizing CC strains is a valid approach for gene network discovery in cardiovascular disease, enabling more accurate clinical risk assessment and prediction
Los planes de estudio en la formación del maestro en Educación Primaria en el espacio europeo de educación superior. Un estudio empírico para conocer de dónde venimos y adónde vamos
Ante los cambios estructurales y metodológicos que suponen las nuevas titulaciones
del Grado de Magisterio surgidas en el marco del Espacio Europeo de Educación
Superior (EEES), en este artículo establecemos la comparación de los contenidos formativos
de los distintos planes de estudio desde que se constituyó la Escuela Universitaria
de Formación del profesorado de EGB de Melilla hasta la propuesta del Libro Blanco
de Magisterio (ANECA, 2005); y recogemos la valoración del futuro plan de estudio
del Grado de Maestro de Educación Primaria por parte de los colectivos vinculados:
profesores de la Facultad de Educación y Humanidades de Melilla, maestros en ejercicio
y alumnos en el último año de sus estudios de Magisterio, al mismo tiempo que nos informan
sobre sus necesidades formativas en las didácticas específi cas.Given the structural and methodological changes that suppose the new Degrees of
Teacher’s Formation emerged in the European Higher Education Area (EHEA), in this article we compare the formative contents of the curricula since it was constituted the
University School of Formation of Melilla until the proposal of White Book of Teaching
in 2005. Also, we have investigated the valuation of the future curricula of formation
of primary school teachers on the part of the following groups: teachers of the Faculty
of Education and Humanities of Melilla, teachers of primary schools and pupils in the
latter year of his studies, at the same time as they inform us about his specifi c formative
needs.Facultad de Educación y Humanidades - Campus de Melilla (Universidad de Granada
Coccolithophore calcification is independent of carbonate chemistry in the tropical ocean
Marañón, Emilio ... et al.-- 13 pages, 7 figures, 1 table, supporting information https://dx.doi.org/10.1002/lno.10295Short-term experiments indicate that seawater acidification can cause a decrease in the rate of calcification by coccolithophores, but the relationship between carbonate chemistry and coccolithophore calcification rate in natural assemblages is still unclear. During the Malaspina 2010 circumnavigation, we measured primary production, calcification, coccolithophore abundance, particulate inorganic carbon (PIC) concentration, and the parameters of the carbonate system, along basin-scale transects in the tropical Atlantic, Indian and Pacific oceans. Euphotic layer-integrated calcification and mean cell-specific calcification in the euphotic layer ranged between 2–10 mgC m−2 d−1 and 5–20 pgC cell−1 d−1, respectively. We found a significant relationship between primary production and calcification, such that the calcification to primary production (CP/PP) ratio was relatively invariant among ocean basins, with an overall mean value of 0.05 ± 0.04. Extrapolating this value to the entire ocean would result in a global pelagic calcification rate of 2.4 PtC yr−1. The mean PIC concentration in surface waters was 1.8 ± 1.6 mgC m−3 and its turnover time averaged 20 d. We combined our data of calcification, primary production, and carbonate chemistry from Malaspina 2010 with those obtained during two previous cruises in the northern Arabian Sea. Both the CP/PP ratio and cell-specific calcification were largely constant across a wide range of calcite saturation state (1.5–6.5), [ inline image]/[H+] (0.08–0.24; mol: μmol), and pH (7.6–8.1), which indicates that calcification by natural coccolithophore assemblages was independent of carbonate chemistry. Our results suggest that coccolithophore calcification, at least in tropical regions, may not be decreasing in the currently acidifying oceanFunding for this study was provided by the Spanish Ministry of Science and Innovation through research projects Malaspina 2010 (grant no. CSD2008-00077), PERSEO (CTM2007-28925-E/MAR), MANIFEST (CTM2012-32017) and TERRIFIC (CTM2014-53582-R). Funding for W.M.B. came from the NSF (OCE-0961660; OCE1220068), NASA (NNX11AO72G; NNX11AL93G; NNX14AQ41G; NNX14AQ43A; NNX14AL92G; NNX14AM77G) and NOAA (NA11OAR4310055).Peer Reviewe
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