Pla de gestió de recursos hídrics del canal de Corral Quemado (Argentina)

El problema real pel que s’ha proposat una solució es centra en el mal estat del canal de Corral Quemado (Argentina) i la repartició desigual dels seus recursos hídrics. A partir de l’estada a la regió afectada per la problemàtica, de l’estudi de l’estat actual dels recursos hídrics i de la demanda a la zona, s’han plantejat diferents alternatives per remodelar i gestionar el canal, adaptades a la realitat del problema. Després d’analitzar les alternatives de remodelació i gestió, es considerà que el revestiment de canal amb formigó amb una secció òptima per transportar el cabal de disseny és l’opció adequada per solucionar els problemes estructurals que presenta el canal. La distribució de cabal continu proporcional a les demandes de cada paraje és l’alternativa escollida per gestionar els recursos hídrics del canal. Opció que proporciona a cada paraje el cabal necessari per satisfer les seves necessitats hídriques bàsiques

Experimental and computational evidence of the biradical structure and reactivity of titanium(IV) enolates

Quantum chemical calculations have unveiled the unexpected biradical character of titanium(IV) enolates from N-acyl oxazolidinones and thiazolidinethiones. The electronic structure of these species therefore involves a valence tautomerism consisting of an equilibrium between a closed shell (formally Ti(IV) enolates) and an open shell, biradical, singlet (formally Ti(III) enolates) electronic states, whose origin is to be basically found in changes of the Ti−O distance. Spectroscopic studies of the intermediate species lend support to such a model, which also turns out to be crucial for a better understanding of the overall reactivity of titanium(IV) enolates. In this context, a thorough computational analysis of the radical addition of titanium(IV) enolates from N-acyl oxazolidinones to TEMPO has permitted us to suggest an entire mechanism, which accounts for the experimental details and the diastereoselectivity of the process. All together, this evidence highlights the relevance of biradical intermediates from titanium(IV) enolates and may be a useful contribution to the foundations of a more insightful comprehension of the structure and reactivity of titanium(IV) enolates

General and stereoselective aminoxylation of biradical titanium(IV) enolates with TEMPO: a detailed study on the effect of the chiral auxiliary

A comprehensive analysis of the influence of the chiral auxiliary on the α-aminoxylation of titanium(IV) enolates with TEMPO indicated that (S) 4-tert-butyl-1-oxazolidine-2-thione is the most appropriate scaffold to provide a single diastereomer in high yields for a variety of substrates, which converts such a radical reaction into a highly chemo- and stereoselective oxidatio

Una mirada al treball amb perspectiva de gènere a Vontovorona, Madagascar

El principal interès d'aquest treball és fixar l'atenció en les relacions entre el treball i el gènere d'una societat on hi predomina el modus de producció de subsistència; centrat en la divisió sexual del treball i, més específicament, en la situació de les dones

L'estudi de casos en Fisiologia: primer esglaó cap a la Dietoteràpia

Es presenta el disseny d'activitats basades en casos perser treballades al llarg del grau de Nutrició Humana i Dietètica, seguint una progressió en el nivell competencial dels estudiants. Els casos s'iniciaran a la Fisiologia Humana de primer curs, seguint per l'Ampliació de Fisiologia Humana, fins arribar a les Patologies i Dietoteràpies de tercer. D'aquesta manera es pretén la integració de continguts, l'aprenentatge reflexiu dels estudiants i la consolidació de coneixements i capacitats

Apolipoprotein E and sex modulate fatty acid metabolism in a prospective observational study of cognitive decline

Background: Fatty acids play prominent roles in brain function as they participate in structural, metabolic and signaling processes. The homeostasis of fatty acids and related pathways is known to be impaired in cognitive decline and dementia, but the relationship between these metabolic disturbances and common risk factors, namely the ɛ4 allele of the apolipoprotein E (ApoE-ɛ4) gene and sex, remains elusive. Methods: In order to investigate early alterations associated with cognitive decline in the fatty acid-related serum metabolome, we here applied targeted metabolomics analysis on a nested case-control study (N=368), part of a prospective population cohort on dementia. Results: When considering the entire study population, circulating levels of free fatty acids, acyl-carnitines and pantothenic acid were found to be increased among those participants who had greater odds of cognitive decline over a 12-year follow-up. Interestingly, stratified analyses indicated that these metabolomic alterations were specific for ApoE-ɛ4 non-carriers and women. Conclusions: Altogether, our results highlight that the regulation of fatty acids and related metabolic pathways during ageing and cognitive decline depends on complex inter-relationships between the ApoE-ε4 genotype and sex. A better understanding of the ApoE-ɛ4 and sex dependent modulation of metabolism is essential to elucidate the individual variability in the onset of cognitive decline, which would help develop personalized therapeutic approaches

INTERSTICE. Encounters between artists, children and educators. Thoughts in-between the arts and education

INTERSTICE is an Erasmus+ project developed by universities, artists and cultural settings from Catalonia, United Kingdom, Italy, and Norway to promote spaces of encounter between educators, artists, and children, to improve our learning processes and to build a pedagogy of co-creation through the arts. This is the main product of INTERSTICE project, a collaborative book where project partners share the key ingredients that we think are necessary to build creative approaches to learning

High-performance liquid chromatography–tandem mass spectrometry in the identification and determination of phase I and phase II drug metabolites

Applications of tandem mass spectrometry (MS/MS) techniques coupled with high-performance liquid chromatography (HPLC) in the identification and determination of phase I and phase II drug metabolites are reviewed with an emphasis on recent papers published predominantly within the last 6 years (2002–2007) reporting the employment of atmospheric pressure ionization techniques as the most promising approach for a sensitive detection, positive identification and quantitation of metabolites in complex biological matrices. This review is devoted to in vitro and in vivo drug biotransformation in humans and animals. The first step preceding an HPLC-MS bioanalysis consists in the choice of suitable sample preparation procedures (biomatrix sampling, homogenization, internal standard addition, deproteination, centrifugation, extraction). The subsequent step is the right optimization of chromatographic conditions providing the required separation selectivity, analysis time and also good compatibility with the MS detection. This is usually not accessible without the employment of the parent drug and synthesized or isolated chemical standards of expected phase I and sometimes also phase II metabolites. The incorporation of additional detectors (photodiode-array UV, fluorescence, polarimetric and others) between the HPLC and MS instruments can result in valuable analytical information supplementing MS results. The relation among the structural changes caused by metabolic reactions and corresponding shifts in the retention behavior in reversed-phase systems is discussed as supporting information for identification of the metabolite. The first and basic step in the interpretation of mass spectra is always the molecular weight (MW) determination based on the presence of protonated molecules [M+H]+ and sometimes adducts with ammonium or alkali-metal ions, observed in the positive-ion full-scan mass spectra. The MW determination can be confirmed by the [M-H]- ion for metabolites providing a signal in negative-ion mass spectra. MS/MS is a worthy tool for further structural characterization because of the occurrence of characteristic fragment ions, either MSn analysis for studying the fragmentation patterns using trap-based analyzers or high mass accuracy measurements for elemental composition determination using time of flight based or Fourier transform mass analyzers. The correlation between typical functional groups found in phase I and phase II drug metabolites and corresponding neutral losses is generalized and illustrated for selected examples. The choice of a suitable ionization technique and polarity mode in relation to the metabolite structure is discussed as well