University of Valencia
Repositori d'Objectes Digitals per a l'Ensenyament la Recerca i la CulturaNot a member yet
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Conservación de Especies No Carismáticas en el aula: propuestas de abordaje a través de medios audiovisuales
Get PDFEste estudio diseña una intervención didáctica para la conservación de las Especies No Carismáticas (ENC) mediante medios audiovisuales, basada en las concepciones de estudiantes de noveno grado de un colegio privado en Neiva, Huila (Colombia). Se empleó un enfoque cualitativo, analizando cuestionarios de ideas previas con Atlas.ti. Los resultados evidenciaron actitudes de aversión hacia las ENC y un uso limitado de medios audiovisuales en educación. Como respuesta, se diseñó una intervención basada en el Aprendizaje Basado en Proyectos (ABP) y el Aprendizaje en Contexto, con actividades de fotografía y producción de reels en Instagram. Se concluye que los medios audiovisuales pueden transformar actitudes y fortalecer la educación ambiental, promoviendo la conservación de las ENC. Esta propuesta es replicable en distintos contextos educativos, fomentando el uso de herramientas digitales en la enseñanza de la biología
Concepciones sobre la Conquista de América en escuelas públicas españolas: dos estudios de caso en Madrid y La Rioja
Get PDFEl presente artículo aborda el problema de la enseñanza de la Historia de América en el contexto escolar español. Específicamente, se estudian las percepciones de alumnos sobre el mencionado asunto en dos centros educativos públicos españoles (uno en Madrid, otro en La Rioja) con el fin de conocer y comprender las concepciones de jóvenes estudiantes de 3º de la ESO acerca de un hecho histórico no exento de polémica en la actualidad: la Conquista de América. Para ello, se utilizó una encuesta escrita en escala Likert (de 0 a 5) en 96 estudiantes y de forma individualizada. Los resultados nos revelaron concepciones limitadas del fenómeno histórico con posicionamientos cercanos a los relatos legendarios sobre la Conquista de América, lo cual nos indica una formación en Historia de América de escaso rigor académico
Patterns of change and continuity in ochre use during the late Middle Stone Age of the Horn of Africa: the Porc-Epic Cave record
Get PDFOchre is found at numerous Middle Stone Age (MSA) sites and plays a key role in early modern human archaeology. Here we analyse the largest known East African MSA ochre assemblage, comprising 40 kg of ochre, found at Porc-Epic Cave, Ethiopia, spanning a period of at least 4,500 years. Visual characterisation of ochre types, microscopic identification of traces of modification, morphological and morphometric analysis of ochre pieces and modified areas, experimental reproduction of grinding processes, surface texture analysis of archaeological and experimentally ground ochre facets, laser granulometry of ochre powder produced experimentally on different grindstones and by Hamar and Ovahimba women from Ethiopia and Namibia respectively, were, for the first time, combined to explore diachronic shifts in ochre processing technology. Our results identify patterns of continuity in ochre acquisition, treatment and use reflecting both persistent use of the same geological resources and similar uses of iron-rich rocks by late MSA Porc-Epic inhabitants. Considering the large amount of ochre processed at the site, this continuity can be interpreted as the expression of a cohesive cultural adaptation, largely shared by all community members and consistently transmitted through time. A gradual shift in preferred processing techniques and motions is interpreted as reflecting cultural drift within this practice. Evidence for the grinding of ochre to produce small quantities of powder throughout the sequence is consistent with a use in symbolic activities for at least part of the ochre assemblage from Porc-Epic Cave
An emended and amplified description of Pecopteris apicalis Knight, a fern morphospecies of mid-Stephanian age from NW Spain
No full textExtensive adpression material of the fern morphospecies Pectopteris apicalis Knight has been collected from overburden from opencast mining in the Paragido-Vallejo area oh the Barruelo Coalfield, close to the collection site of the holotype of the species. This has permitted a more detailed description of the key characteristics than was previously possible and an emended diagnosis. The large frond fragments demonstrate large pinnae of antepenultimate order, length in excess of 0.4 m, with apparent attachment to a very robust petiole in a tripinnate frond structure. Other diagnostic features of the species confirmed in this wide range of material cover the dimensions, acuminate shape, and terminal of last order pinnae, the range of dimensions and shape of pinnules and the characteristic consistently bifurcate venation. Fertile organs have been identified only on one specimen collected from another opencast working in the Barruelo Coalfield, at a lower level in the same stratigraphic unit. Although indistinct, the fertile organs comprise two rows of small circular sori on either side of the mid-vein, reminiscent of the genus Asterotheca, although the material does not permit reliable identification. Discussion of the possible systematic relationship of this species suggests the closet affiliation is with the cyatheoid group of pecopterid marattialean species. The Peragido-Vallejo material occurs within a low diversity flora which has undergone minimal transport from its site of growth, interpreted as in an interdistributary back-swamp area on a near-coastal alluvial plai
La pesca en la ciudad romana de Tróia (Carvalhal, Portugal): reconstrucción de los aparejos de caña y sedal a partir de los anzuelos
Get PDFTróia (Carvalhal, Portugal) constituye uno de los grandes centros pesquero-conserveros del mundo romano, tal y como ponen de manifiesto los restos arquitectónicos actualmente conservados en el yacimiento, pertenecientes mayoritariamente a cetariae. Otras evidencias que verifican la importancia de las actividades haliéuticas en Tróia son las artes de pesca, documentándose un gran número de instrumental pesquero que ha sido objeto de estudio recientemente en el Museo Nacional de Arqueología de Lisboa. Los materiales, procedentes de antiguas excavaciones y casi en su mayoría inéditos, se corresponden con anzuelos, pesas, agujas y lanzaderas. En este trabajo se dan a conocer los anzuelos de pesca (setenta y siete ejemplares), presentándose un análisis morfo-tipológico y métrico de los mismos, comparándose la muestra inventariada con otros conjuntos de anzuelos romanos estudiados en la Península Ibérica como es el caso de la ciudad hispanorromano de Baelo Claudia.
Down-Regulation of the Longevity-Associated Protein SIRT1 in Peripheral Blood Mononuclear Cells of Treated HIV Patients
Get PDFThe activity of sirtuin 1 (SIRT1), a class III histone deacetylase with a critical role in several biological functions, decreases with age and its deficiency is associated with many inflammatory and age-related diseases. It also regulates the chronic immune activation and viral latency during an HIV infection. The life-span and particularly the health span of HIV patients are substantially shortened; however, the participation of SIRT1 in these effects is not clear. We performed a prospective cross-sectional monocentric study that included 70 HIV-infected patients and 43 BMI-, age- and sex-matched uninfected individuals. We found that in the PBMCs of the HIV patients, SIRT1 mRNA levels were significantly lower (p < 0.0001). This decrease, which was corroborated at the protein level, occurred irrespectively of the antiretroviral regimen these patients received and was not significantly related to the general, HIV-related or comorbidity-related parameters. The levels of the major mitochondrial sirtuin SIRT3 were not altered. Moreover, the strong correlations of SIRT1 with the leukocyte markers CD8A and CD19 present in the uninfected individuals were absent in the HIV patients. In conclusion, this study showed that the PBMCs of the HIV patients displayed diminished SIRT1 levels and altered correlations of SIRT1 with markers of CD8+ T cells and B cells, findings which may be relevant for understanding the complex pathogenic milieu in HIV patients
Dual regulation of the levels and function of Start transcriptional repressors drives G1 arrest in response to cell wall stress
Get PDFBackground Many different stress signaling pathways converge in a common response: slowdown or arrest cell cycle in the G1 phase. The G1/S transition (called Start in budding yeast) is a key checkpoint controlled by positive and negative regulators. Among them, Whi7 and Whi5 are transcriptional repressors of the G1/S transcriptional program, yeast functional homologs of the Retinoblastoma family proteins in mammalian cells. Under standard conditions, Whi7 plays a lesser role than Whi5 in Start inhibition. However, under cell wall stress, Whi7 is induced and plays a more important role in G1/S control. In this work, we investigated the functional hallmarks of Whi7 and Whi5, which determine their strength as Start inhibitors under cell wall stress. Methods The response of Saccharomyces cerevisiae to Calcofluor White was investigated to characterize the regulation and function of Whi7 and Whi5 under cell wall stress. To control their protein levels, we used dose-dependent β-estradiol-induced expression and auxin-induced degron protein fusions. We also performed Chromatin Immunoprecipitation assays to investigate Whi7 and Whi5 association with Start promoters and scored cell cycle arrest and re-entry using cell microscopy assays. Results We found that cell wall stress promoted the specific upregulation of the Whi7 Start repressor. First, although cell wall stress increases Whi7 protein levels, this is not the only determinant behind the Whi7 function in promoting G1 arrest. Indeed, artificial induction of Whi5 at the same protein level resulted in a lower G1 block. Second, under cell wall stress, Whi7 was specifically recruited to SBF-target promoters, independent of the increase in its protein levels or cell cycle stage. Finally, we found that Whi7 protein instability further increased during cell wall stress and that Whi7 degradation triggered advanced cell cycle re-entry. Conclusions Here, we show that cell wall stress signaling specifically enhances Whi7 function as a Start transcriptional repressor. Importantly, we identified new Whi7-specific regulatory mechanisms that do not operate in the Whi5 repressor. Our results indicate that cells may benefit from stress-specific repressors to ensure the stress-induced G1 arrest and that Whi7 rapid degradation may be particularly important to resume cell cycle upon adaptation
Two novel mutations in TBC1D32 add complexity to the oro-facial-digital syndrome
Get PDFBackground: Ciliopathies are characterized by the dysfunction of cilia, being inherited retinal dystrophies (IRDs) included in sensory ciliopathies. Besides, oro-facial-digital syndrome (OFD) is caused by mutations in ciliary genes, leading to dysmorphic features. Mutations in TBC1D32 were associated to retinal dystrophy and OFD, defining this form as OFD-IX. Results: A clinical exome analysis performed on a patient presenting with OFD-IX and sensorineural hearing loss (SNHL) identified two variants in TBC1D32, one of which affects splicing, with its impact validated using a minigene assay. Conclusions: These results suggest that SNHL may represent a new clinical feature associated with this gene
Parole del mare. Il contributo catalano al lessico sardo della pesca
Get PDFRiassunto: La Sardegna, per motivi storici, non possiede tradizioni nell’ambito marinaresco, ma i suoi abitanti hanno lasciato che fossero i popoli stranieri (dapprima catalani e spagnoli, poi campani, siciliani e liguri) ad occuparsi delle professioni relative al mare: da qui discende il fatto che anche il lessico pertinente a questa sfera lessicale è composito ed è stato interamente preso a prestito da altre lingue. Il contributo si concentra in particolare sugli apporti del catalano al lessico nautico e marittimo, che appaiono cospicui e pervasivi, e coprono vari ambiti che vanno dai vocaboli del porto e della pesca, con le relative attrezzature, fino alle più umili denominazioni dei pesci di mare, dei crostacei e dei molluschi. Parole chiave: lessico marinaresco, ittionimia, lingua sardaAbstract: Sardinia, for historical reasons, does not have traditions in the maritime field, but its inhabitants allowed foreign peoples (first Catalans and Spaniards, then fishermen from Campania, Sicily, and Liguria) to take care of professions related to the sea. As a result, the relevant lexicon in this linguistic sphere is composite and entirely borrowed from other languages. The essay specifically focuses on the contributions of Catalan to the nautical and fishing lexicon, which appear substantial and pervasive, covering various areas ranging from port and fishermen terms, along with their respective equipment, to the humblest names of sea fish, crustaceans, and mollusks.Keywords: Maritime lexicon, ichthyonymia, Sardinian languag