University of Valencia
Repositori d'Objectes Digitals per a l'Ensenyament la Recerca i la CulturaNot a member yet
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A unique gene cluster for the utilization of the mucosal and human milk-associated glycans galacto-N-biose and lacto-N-biose in Lactobacillus casei
No full textThe probiotic Lactobacillus casei catabolizes galacto-N-biose (GNB) and lacto-N-biose (LNB) by using a transport system and metabolic routes different from those of Bifidobacterium. L. casei contains a gene cluster, gnbREFGBCDA, involved in the metabolism of GNB, LNB and also N-acetylgalactosamine. Inactivation of gnbC (EIIC) or ptsI (Enzyme I) of the phosphoenolpyruvate : sugar phosphotransferase system (PTS) prevented the growth on those three carbohydrates, indicating that they are transported and phosphorylated by the same PTS(Gnb) . Enzyme activities and growth analysis with knockout mutants showed that GnbG (phospho-β-galactosidase) hydrolyses both disaccharides. However, GnbF (N-acetylgalactosamine-6P deacetylase) and GnbE (galactosamine-6P isomerase/deaminase) are involved in GNB but not in LNB fermentation. The utilization of LNB depends on nagA (N-acetylglucosamine-6P deacetylase), showing that the N-acetylhexosamine moieties of GNB and LNB follow different catabolic routes. A lacAB mutant (galactose-6P isomerase) was impaired in GNB and LNB utilization, indicating that their galactose moiety is channelled through the tagatose-6P pathway. Transcriptional analysis showed that the gnb operon is regulated by substrate-specific induction mediated by the transcriptional repressor GnbR, which binds to a 26 bp DNA region containing inverted repeats exhibiting a 2T/2A conserved core. The data represent the first characterization of novel metabolic pathways for human milk oligosaccharides and glycoconjugate structures in Firmicute
3D-printed chemiluminescence flow cells with customized cross-section geometry for enhanced analytical performance
No full textLow force stereolithography is exploited for the first time for one-step facile fabrication of chemiluminescence (CL) flow-through cells that bear unrivalled features as compared to those available through milling or blowing procedures or alternative 3D printing technologies. A variety of bespoke cross-section geometries with polyhedral features (namely, trigonal, cubic, and five-side prism) as well as semicircular crosssection are herein critically evaluated in terms of analytical performance against the standard cylindrical cross-section in a flat spirally-shape format. The idea behind is to maximize capture of elicited light by the new designs while leveraging 3D printing further for fabrication of (i) customized gaskets that enable reliable attaching of the active mixing zone of the CL cell to the detection window, (ii) in-line 3D printed serpentine reactors, and (iii) flow confluences with tailorable shapes for enhancing mixing of samples with CL reagents. Up to twenty transparent functional cells were simultaneously fabricated without inner supports following post-curing and surface treatment protocols lasting less than 5 h. In fact, previous attempts to print spirallyshaped cells in one-step by resorting to less cost effective photopolymer inkjet printing technologies were unsuccessful because of the requirement of lengthy procedures (> 15 days) for quantitative removal of the support material. By exploiting the phthalazinedione-hydrogen peroxide chemistry as a model reaction, the five-side irregular pentagon cell exhibited superior analytical figures of merit in terms of LOD, dynamic range and intermediate precision as compared to alternative designs. Computational fluid dynamic simulations for mapping velocities at the entry region of the spiral cell corroborated the fact that the 5-side prism flow-cell with Y-type confluence permitted the most efficient mixing of reagents and sample while enabling larger flow velocities near the inlet that contribute to a more efficient capture of the photons from the flash-type reaction. The applicability of the 3D printed 5-side prism CL cell for automatic determination of hydrogen peroxide using a computerized hybrid flow system was demonstrated for the analysis of high matrix samples, viz., seawater and saliva, with relative recoveries ranging from 83 to 103%
Las preferencias musicales de los estudiantes de 5º y 6º de Educación Primaria. Una oportunidad para implementar un enfoque de tipo sociocrítico
No full textLa música juega un papel fundamental en la vida de los adolescentes, ya que influye en la construcción de sus identidades culturales. La implementación de un enfoque de tipo sociocrítico en la didáctica de la música implica la utilización de un repertorio vinculado a dichas identidades que permita reflexionar sobre las relaciones existentes entre música y sociedad y que ofrezca a los estudiantes herramientas para comprender su entorno social. Los objetivos de este estudio son c onocer cuáles son las preferencias musicales de los estudiantes de 5º y 6º de Educación Primaria, qué características tienen y el lugar que ocupan en el currículum. De esta forma, se ofrece a los docentes un conocimiento más profundo sobre la realidad musical extraescolar de sus alumnos, así como un marco de reflexión a partir del cual incorporar dicho repertorio en el aula desde una perspectiva crítica. Para ello, se ha aplicado un cuestionario a una muestra de 199 estudiantes de centros educativos de la ciudad de Valencia. Los resultados indican que la música popular urbana es el repertorio preferido por dichos estudiantes, especialmente los estilos de pop, hip-hop y música electrónica. Sin embargo, este repertorio tiene una representación prácticamente nula tanto en las prácticas educativas de los docentes como en los manuales escolares que estos utilizan
Relevance of Nrf2 and heme oxygenase-1 in articular diseases
No full textJoint conditions pose an important public health problem as they are a leading cause of pain, functional limitation and physical disability. Oxidative stress is related to the pathogenesis of many chronic diseases affecting the joints such as rheumatoid arthritis and osteoarthritis. Cells have developed adaptive protection mechanisms to maintain homeostasis such as nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2) which regulates the transcription of many genes involved in redox balance, detoxification, metabolism and inflammation. Activation of Nrf2 results in the synthesis of heme oxygenase-1 (HO-1) leading to the formation of a number of bioactive metabolites, mainly CO, biliverdin and bilirubin. Ample evidence supports the notion that Nrf2 and HO-1 can confer protection against oxidative stress and inflammatory and immune responses in joint tissues. As a consequence, this pathway may control the activation and metabolism of articular cells to play a regulatory role in joint destruction thus offering new opportunities for better treatments. Further studies are necessary to identify improved strategies to regulate Nrf2 and HO-1 activation in order to enable the development of drugs with therapeutic applications in joint diseases
Multilevel model in economics: A way to test the natural parter hypothesis
No full textThis study applies multilevel modelling to the analysis of trade flows. This methodology can complement the use of the standard gravity equation in addressing the influence of geographical distance on the impact of trade agreements on bilateral trade (the natural-partner hypothesis). The analysis suggests that the simplest, most obvious, and best way to nest country pairs with international trade data is by distance. To this end, a sample of 69 countries with data on domestic flows over the period 1986-2016 was used. This sample accounts for around 85% of world trade data. The estimations suggest that the pro-trade effects of preferential trade agreements decrease with distance to trade partners, while this does not occur with the multilateral trading system. What is more interesting is that the former result only holds for the preferential trade agreements involving goods, which supports the natural-trading partner hypothesis, but not for those that include services. In the latter case, the impact increases with distance. This suggests that deeper preferential trade agreements reduce the cost of distance as a barrier to trade, which probably reflects cultural (regulation) distance
Do COVID-19 Worries, Resilience and Emotional Distress Influence Life Satisfaction? Outcomes in Adolescents in Ecuador during the Pandemic: SEM vs. QCA
No full textCOVID-19 and the measures adopted have been a problem for society at all levels. The aim of the study was to analyze the main predictors of life satisfaction among adolescents in Ecuador during the COVID-19 pandemic. Participants were 902 adolescents from Ecuador aged between 12 and 18 years (M = 15.30; SD = 1.28). Variables such as life satisfaction, resilience, emotional symptomatology, and worries about COVID-19 were assessed. Two statistical methodologies were compared (structural equation models (SEM) and qualitative comparative analysis (QCA)) to analyze the possible influence of worries about COVID-19, resilience and emotional symptomatology towards life satisfaction. The results indicated that in both models, worries about COVID-19 were negatively related to life satisfaction. However, having a greater worry, specifically for physical health issues, was associated with better life satisfaction. SEM models indicate that depression is negatively related to life satisfaction. In QCA models, high levels of life satisfaction are explained by low levels of anxiety and depression. Thus, resilience seems to play a mediating role in life satisfaction, although this is only true for the depression variable. It is necessary to detect signs of risk in this population and strengthen resilience in them as elements that can facilitate their adequate coping with their adverse situation
A twenty-year bibliometric analysis on the relationship between complicated grief and attachment
No full textAttachment theory is a key paradigm for understanding individual differences for the elaboration of the grieving processes, however limited attempts to systematically synthesize are found on the literature. Our aim is to conduct a bibliometric analysis about the relationship between complicated grief and attachment over the past twenty years. A bibliographic search was made in the Core Collection of Web of Science, the bibliometric analysis was performed using the software Hiscite version 2010.12.6, and VosViewer were used for the construction of bibliometric maps. Results show 276 publications from 2003 until 2023 from 789 authors, published in 143 scientific journals. The field presents a regular increase and sustained number of publications. The topics most researched were bereavement, complicated grief and attachment, and since 2018 has been increased interest in prolonged grief disorder. In conclusion, this bibliometric analysis contributes to the understanding of the current state of this topic and its evolution, being relevant to consider attachment style in bereavement intervention
Mapping of sexist violence in Valencia (Spain)
No full textThis article examines the ways in which issues of women's safety in public spaces might be integrated into artistic practices in art education from an intersectional and queer review of gender in the city. It considers the contributions from human geography, feminism and affect theory, trying to incorporate all of those perspectives into a pedagogical proposal. The first part of the article introduces the main issues to be explored, acknowledging them in the context of recent public debates in Spain that were related to gender and urban safety. The second part presents the results of a participatory, ephemeral, vindictive and artistic action developed with students of a master's degree in Secondary Education Teaching in the specialty of visual arts at the University of Valencia: An action of mapping the sexist violence in Valencia. Lastly, the article concludes with the presentation of emotional and educational profits gained by used practices
The climatic challenge: Which plants will people use in the next century?
No full textMore than 31,000 useful plant species have been documented to fulfil needs and services for humans or the animals and environment we depend on. Despite this diversity, humans currently satisfy most requirements with surprisingly few plant species; for example, just three crops - rice, wheat and maize - comprise more than 50% of plant derived calories. Here, we synthesize the projected impact of global climatic change on useful plants across the spectrum of plant domestication. We illustrate the demographic, spatial, ecophysiological, chemical, functional, evolutionary and cultural traits that are likely to characterise useful plants and their resilience in the next century. Using this framework, we consider a range of possible pathways for future human use of plants. These are centred on two trade-offs: i) diversification versus specialization in the range of species we utilize, and ii) substitution of the species towards those better suited to future climate versus facilitating adaptation in our existing suite of dominant useful plants. In the coming century, major challenges to agriculture and biodiversity will be dominated by increased climatic variation, shifting species ranges, disruption to biotic interactions, nutrient limitation and emerging pests and pathogens. These challenges must be mitigated, whilst enhancing sustainable production to meet the needs of a growing population and a more resource intensive standard of living. With the continued erosion of biodiversity, our future ability to choose among these pathways and trade-offs is likely to be diminished
Selective attention (SA) and perceptual inhibition (PI) throughout the lifespan
No full textThe aim of this study was to analyze the development of Perceptual Inhibition (PI) and Selective Visual Attention (SVA) across lifespan, identifying key moments of change in the direction of development. A total of 810 Argentinian participants, ranging from 6-80 years, were included. The results revealed that PI and SVA followed similar patterns, characterized by a linear function with three phases and two significant transition zones. The first phase spanned from childhood to early adolescence, showing a rapid and constant improvement in PI and SVA efficiency until 11 and 13 years. Subsequently, the next developmental phase is more extensive and lasts about 40 years. This phase is characterized by stability with a slight decline. In older adults another transition was identified, with a progressive decline until 80 years. It is important to note that the decline in older adults was much slower than the rapid improvement observed in childhood and adolescence, suggesting that the decline in older adults was not an inverse mirror image of their early development. PI showed a continuous improvement between the ages of 6 and 11, reaching a similar level of performance as young adults. On the other hand, SVA indexes showed a linear and progressive improvement from 6 years of age, but the first transition in the other direction was registered at 13 years of age. In summary, this study highlighted that both PI and SVA followed nonsymmetrical developmental patterns, with rapid early improvements in childhood and adolescence, and a slower decline in older adult