Contrasting effects of ocean warming on different components of plant-herbivore interactions

Este artículo contiene 11 páginas, 6 figuras, 1 tabla.There is increasing uncertainty of how marine ecosystems will respond to rising temperatures. While studies have focused on the impacts of warming on individual species, knowledge of how species interactions are likely to respond is scant. The strength of even simple two-species interactions is influenced by several interacting mechanisms, each potentially changing with temperature. We used controlled experiments to assess how plantherbivore interactions respond to temperature for three structural dominant macrophytes in the Mediterranean and their principal sea urchin herbivore. Increasing temperature differentially influenced plant-specific growth, sea urchin growth and metabolism, consumption rates and herbivore preferences, but not movement behaviour. Evaluating these empirical observations against conceptual models of plant-herbivore performance, it appears likely that while the strength of herbivory may increase for the tested macroalga, for the two dominant seagrasses, the interaction strength may remain relatively unchanged or even weaken as temperatures rise. These results show a clear set of winners and losers in the warming Mediterranean as the complex factors driving species interactions change.The Spanish Ministry of Science and Innovation funded this research (projects CMT2010-22273- C02-01-02 and CMT2013-48027-C03-R) and supported JB (scholarship BES-2011-043630). The Spanish National Research Council supported RA's visitorship (CSIC-201330E062). TS was supported by an Australian Government Endeavour Fellowship. JFP acknowledges financial support from the Welsh Government and Higher Education Funding Council for Wales through the Sȇr Cymru National Research Network for Low Carbon, Energy and Environment. Support to FT was provided by the Ramón y Cajal Programme (RYC-2011-08572).Peer reviewe

Indirect grazing-induced mechanisms contribute to the resilience of Mediterranean seagrass meadows to sea urchin herbivory

Plant–herbivore interactions are often regulated by a series of direct and indirect buffer mechanisms (compensatory or defensive plant responses, population control, alternative resources) that can determine the relative stability of the system. In plant-dominated marine environments, these mechanisms are particularly important given how vulnerable these systems are to strong consumer pressure. Here, we evaluate the presence and, where possible, the strength, of five mechanisms that get activated under high herbivory pressure and are capable of dampening their effects in a seagrass meadow ecosystem: 1) seagrass compensatory growth, 2) increase in plant resistance, 3) availability of alternative resources, 4) predatory control and 5) density-dependent control. We assessed these mechanisms for the interaction between the Mediterranean seagrass Posidonia oceanica and the sea urchin Paracentrotus lividus through a short-term series of controlled field and laboratory experiments after simulated or natural herbivory events. Of the five mechanisms tested, we found that three mechanisms – availability of alternative resources, increased predation rate and reduction in sea urchin numbers – effectively dampened herbivory and worked as potential buffering mechanisms. In contrast, plant compensatory growth and resistance did not show clear responses. While compensatory growth and plant resistance are direct plant mechanism to tolerate the effects of herbivory, the rest are indirect mechanisms that begin with a modification of a plant trait (i.e. canopy height) that influences other species preference and/or behaviour, which in turn influences plant consumption. These adaptive behaviours may be a crucial and often overlooked factor in the remarkable resilience that Mediterranean seagrass ecosystems show to herbivory

New Insights on Structures Forming the Lignin-Like Fractions of Ancestral Plants

In the present work, lignin-like fractions were isolated from several ancestral plants –including moss (Hypnum cupressiforme and Polytrichum commune), lycophyte (Selaginella kraussiana), horsetail (Equisetum palustre), fern (Nephrolepis cordifolia and Pteridium aquilinum), cycad (Cycas revoluta), and gnetophyte (Ephedra fragilis) species– and structurally characterized by pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) and two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy. Py-GC/MS yielded marker compounds characteristic of lignin units, except in the H. cupressiforme, P. commune and E. palustre “lignins, ” where they were practically absent. Additional structural information on the other five samples was obtained from 2D-NMR experiments displaying intense correlations signals of guaiacyl (G) units in the fern and cycad lignins, along with smaller amounts of p-hydroxyphenyl (H) units. Interestingly, the lignins from the lycophyte S. kraussiana and the gnetophyte E. fragilis were not only composed of G- and H-lignin units but they also incorporated significant amounts of the syringyl (S) units characteristic of angiosperms, which appeared much later in plant evolution, most probably due to convergent evolution. The latter finding is also supported by the abundance of syringol derivatives after the Py-GC/MS analyses of these two samples. Regarding lignin structure, β−O−4′ alkyl-aryl ethers were the most abundant substructures, followed by condensed β−5′ phenylcoumarans and β−β′ resinols (and dibenzodioxocins in the fern and cycad lignins). The highest percentages of alkyl-aryl ether structures correlated with the higher S/G ratio in the S. Kraussiana and E. fragilis lignin-like fractions. More interestingly, apart from the typical monolignol-derived lignin units (H, G and S), other structures, assigned to flavonoid compounds never reported before in natural lignins (such as amentoflavone, apigenin, hypnogenol B, kaempferol, and naringenin), could also be identified in the HSQC spectra of all the lignin-like fractions analyzed. With this purpose, in vitro synthesized coniferyl-naringenin and coniferyl-apigenin dehydrogenation polymers were used as standards. These flavonoids were abundant in H. cupressiforme appearing as the only constituents of the moss lignin-like fraction (including 84% of dimeric hypnogenol B) and their abundance decreased in those of S. Kraussiana (with amentoflavone and naringenin representing 14% of the total aromatic units), and the two ancient gymnosperms (0.4–1.2%) and ferns (0–0.7%)

Ocular related emergencies in Spain during the COVID-19 pandemic, a multicenter study

Purpose: To evaluate ophthalmological emergencies (OE) during the COVID-19 pandemic comparing them with the same period of the previous year. Methods: Retrospective observational study of all OE visits in four tertiary hospitals in Spain comparing data from March 16th to April 30th, 2020 (COVID-19 period) and the same period of 2019 (pre-COVID-19 period). Severity of the conditions was assessed following Channa et al. publication. Data on demographics, diagnosis and treatments were collected from Electronic Medical Records. Results: During lockdown, OE significantly declined by 75.18%, from 7, 730 registered in the pre-COVID-19 period to 1, 928 attended during the COVID-19 period (p < 0.001). In 2019, 23.86% of visits were classified as emergent, 59.50% as non-emergent, and 16.65% could not be determined. In 2020, the percentage of emergent visits increased up to 29.77%, non-emergent visits significantly decreased to 52.92% (p < 0.001), and 17.31% of the visits were classified as “could not determine”. During the pandemic, people aged between 45 and 65 years old represented the largest attending group (37.89%), compared to 2019, where patients over 65 years were the majority (39.80%). In 2019, most frequent diagnosis was unspecified acute conjunctivitis (11.59%), followed by vitreous degeneration (6.47%), and punctate keratitis (5.86%). During the COVID-19 period, vitreous degeneration was the first cause for consultation (9.28%), followed by unspecified acute conjunctivitis (5.63%) and punctate keratitis (5.85%). Conclusions: OE visits dropped significantly during the pandemic in Spain (75.18%), although more than half were classified as non-urgent conditions, indicating a lack of understanding of the really emergent ocular pathologies among population. © 2021, The Author(s)

Gestió de projectes experimentals al laboratori

Els plans d’estudi d'Enginyeria Química tenen assignatures troncals exclusivament de laboratori. Tot i així, la visió tradicional de la docència al laboratori continua essent la d’unes pràctiques complementàries a les assignatures teòriques. Tanmateix, es pot dotar aquestes assignatures d'un discurs propi basat en l’experimentació com a mètode i aprofitar el fet que el laboratori, a diferència de l'aula, és un escenari idoni per a l’aprenentatge i desenvolupament de competències, actituds i aptituds més enllà de la repetició del procés de mesura i del coneixement dels fonaments fisicoquímics dels fenòmens i processos que s’estudien. Des de fa més de deu anys l’Experimentació en Enginyeria Química de l’EUETIB s’ha plantejat com un procés de millora continua vers aquest objectiu. La formulació d’un pla estratègic que en gestionava la transformació va ser premiada el 2007 i actualment incorpora de manera explícita una sèrie de jocs de rol al laboratori orientats a l’aprenentatge de competències en l’àmbit de l’aplicació del mètode científic, la resolució de problemes, la gestió de projectes, la gestió de la qualitat i la millora contínua, la gestió de la seguretat i el medi ambient, la coavaluació i l’avaluació per a l’aprenentatge i la comunicació i el llenguatge.Peer Reviewe

Plasma Aβ42/40 ratio alone or combined with FDG-PET can accurately predict amyloid-PET positivity: a cross-sectional analysis from the AB255 Study

Background: To facilitate population screening and clinical trials of disease-modifying therapies for Alzheimer’s disease, supportive biomarker information is necessary. This study was aimed to investigate the association of plasma amyloid-beta (Aβ) levels with the presence of pathological accumulation of Aβ in the brain measured by amyloid-PET. Both plasma Aβ42/40 ratio alone or combined with an FDG-PET-based biomarker of neurodegeneration were assessed as potential AD biomarkers. Methods: We included 39 cognitively normal subjects and 20 patients with mild cognitive impairment from the AB255 Study who had undergone PiB-PET scans. Total Aβ40 and Aβ42 levels in plasma (TP42/40) were quantified using ABtest kits. Subjects were dichotomized as Aβ-PET positive or negative, and the ability of TP42/40 to detect Aβ-PET positivity was assessed by logistic regression and receiver operating characteristic analyses. Combination of plasma Aβ biomarkers and FDG-PET was further assessed as an improvement for brain amyloidosis detection and diagnosis classification. Results: Eighteen (30.5%) subjects were Aβ-PET positive. TP42/40 ratio alone identified Aβ-PET status with an area under the curve (AUC) of 0.881 (95% confidence interval [CI] = 0.779–0.982). Discriminating performance of TP42/40 to detect Aβ-PET-positive subjects yielded sensitivity and specificity values at Youden’s cutoff of 77.8% and 87.5%, respectively, with a positive predictive value of 0.732 and negative predictive value of 0.900. All these parameters improved after adjusting the model for significant covariates. Applying TP42/40 as the first screening tool in a sequential diagnostic work-up would reduce the number of Aβ-PET scans by 64%. Combination of both FDG-PET scores and plasma Aβ biomarkers was found to be the most accurate Aβ-PET predictor, with an AUC of 0.965 (95% CI = 0.913–0.100). Conclusions: Plasma TP42/40 ratio showed a relevant and significant potential as a screening tool to identify brain Aβ positivity in preclinical and prodromal stages of Alzheimer’s disease

Environmental and self-sufficiency assessment of the energy metabolism of tourist hubs on Mediterranean Islands : the case of Menorca (Spain)

SostenipraEnergy performance of island tourism has been analyzed in the literature. However, tourist services tend to concentrate in tourist hubs, especially where mass tourism predominates (e.g., Mediterranean), and the energy metabolism of these systems has not yet been assessed. The present paper models and estimates the energy metabolism of tourist hubs in the Menorca Island (Spain) by integrating social, geographical and environmental methods. Mobility (both external and internal) and consumption of lodging services were characterized through surveys to users (tourists) and business managers. An environmental assessment evaluated CO₂ emissions, and energy self-sufficiency potential was estimated via GIS data. The results indicate that, on average, a tourist consumes 4756 MJ with associated emissions of 277 kg of CO₂ per stay (20 days on average). Of all the energy flows, external mobility contributes the most to total emissions (77%). For every day spent in a tourist hub, a tourist consumes between 29 MJ and 93 MJ in lodging services, consumption that could be 100% satisfied by photovoltaic systems, and these systems would result in positive effects for the island. Sustainable tourism management might focus on promoting environmentally friendly transportation, energy efficient practices, and environmental communication through ecolabeling

The membrane-spanning 4-domains, subfamily A (MS4A) gene cluster contains a common variant associated with Alzheimer's disease

Background\ud In order to identify novel loci associated with Alzheimer's disease (AD), we conducted a genome-wide association study (GWAS) in the Spanish population.\ud \ud Methods\ud We genotyped 1,128 individuals using the Affymetrix Nsp I 250K chip. A sample of 327 sporadic AD patients and 801 controls with unknown cognitive status from the Spanish general population were included in our initial study. To increase the power of the study, we combined our results with those of four other public GWAS datasets by applying identical quality control filters and the same imputation methods, which were then analyzed with a global meta-GWAS. A replication sample with 2,200 sporadic AD patients and 2,301 controls was genotyped to confirm our GWAS findings.\ud \ud Results\ud Meta-analysis of our data and independent replication datasets allowed us to confirm a novel genome-wide significant association of AD with the membrane-spanning 4-domains subfamily A (MS4A) gene cluster (rs1562990, P = 4.40E-11, odds ratio = 0.88, 95% confidence interval 0.85 to 0.91, n = 10,181 cases and 14,341 controls).\ud \ud Conclusions\ud Our results underscore the importance of international efforts combining GWAS datasets to isolate genetic loci for complex diseases

Assessing the role of the TREM2 p.R47H variant as a risk factor for Alzheimer's disease and frontotemporal dementia

4 páginas, 1 figura, a tabla. Los autores pertenecen a The dementia genetic Spanish consortium (DEGESCO).A non-synonymous genetic rare variant, rs75932628-T (p.R47H), in the TREM2 gene has recently been reported to be a strong genetic risk factor for Alzheimer's disease (AD). Also, rare recessive mutations have been associated with frontotemporal dementia (FTD). We aimed to investigate the role of p.R47H variant in AD and FTD through a multi-center study comprising 3,172 AD and 682 FTD patients and 2,169 healthy controls from Spain. We found that 0.6% of AD cases carried this variant compared to 0.1% of controls (odds ratio [OR]=4.12, 95% confidence interval [CI]: 1.21-14.00, P=0.014). A meta-analysis comprising 32,598 subjects from four previous studies demonstrated the large effect of the p.R47H variant in AD risk (OR=4.11, 95% CI: 2.99-5.68, P=5.27x10-18). We did not find an association between p.R47H and age of onset of AD or family history of dementia. Finally, none of the FTD patients harbored this genetic variant. These data strongly support the important role of p.R47H in AD risk and suggest that this rare genetic variant is not related to FTD.This study was supported by grants from Instituto de Salud Carlos III (PI12/01311 and 12/00013), grants from the Ministry of Science (SAF2010-15558, SAF2009-10434), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED, Spain), Consolider (CSD2010-00045), and the Department of Health of the Government of Navarra (refs. 13085 and 3/2008). CR held during the period 2009-2013 a “Torres Quevedo” fellowship from the Spanish Ministry of Science and Technology, co-financed by the European Social Fund. Fundació ACE researchers are indebted to Trinitat Port-Carbó and her family who are supporting Fundació ACE scientific programs.Peer reviewe