Light signals generated by vegetation shade facilitate acclimation to low light in shade-avoider plants

[EN] When growing in search for light, plants can experience continuous or occasional shading by other plants. Plant proximity causes a decrease in the ratio of R to far-red light (low R:FR) due to the preferential absorbance of R light and reflection of FR light by photosynthetic tissues of neighboring plants. This signal is often perceived before actual shading causes a reduction in photo-synthetically active radiation (low PAR). Here, we investigated how several Brassicaceae species from different habitats respond to low R:FR and low PAR in terms of elongation, photosynthesis, and photoacclimation. Shade-tolerant plants such as hairy bittercress (Cardamine hirsuta) displayed a good adaptation to low PAR but a poor or null response to low R:FR exposure. In contrast, shade-avoider species, such as Arabidopsis (Arabidopsis thaliana), showed a weak photosynthetic performance under low PAR but they strongly elongated when exposed to low R:FR. These responses could be genetically uncoupled. Most interestingly, exposure to low R:FR of shade-avoider (but not shade-tolerant) plants improved their photoacclimation to low PAR by triggering changes in photosynthesis-related gene expression, pigment accumulation, and chloroplast ultrastructure. These results indicate that low R:FR signaling unleashes molecular, metabolic, and developmental responses that allow shade-avoider plants (including most crops) to adjust their photosynthetic capacity in anticipation of eventual shading by nearby plants.L.M. received a predoctoral fellowships from La Caixa Foundation (INPhINIT fellowship LCF/BQ/IN18/11660004). W.Q. is a recipient of a predoctoral Chinese Scholarship Council (CSC) fellowship. A.I.-S. is supported by a predoctoral fellowship from MICINN (PRE2018-083610). I.F.-S. has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 753301. Our research is supported by grants from MICINN-FEDER (BIO2017-85316-R, and BIO2017-84041-P) and AGAUR (2017-SGR1211, 2017-SGR710 and Xarba) to J.F.M.-G. and M.R.-C. We also acknowledge the support of the MINECO for the "Centro de Excelencia Severo Ochoa 2016-2019" award SEV-2015-0533 and by the CERCA Programme/Generalitat de Catalunya.Morelli, L.; Paulisic, S.; Qin, W.; Iglesias-Sanchez; Roig-Villanova, I.; Florez-Sarasa, I.; Rodriguez Concepción, M.... (2021). Light signals generated by vegetation shade facilitate acclimation to low light in shade-avoider plants. Plant Physiology (Online). 186(4):2137-2151. https://doi.org/10.1093/plphys/kiab206S21372151186

Influence of domestic and environmental weathering in the self-cleaning performance and durability of TiO2 photocatalytic coatings

Weathering of photocatalytic TiO2 coatings represents an important issue for the successful application of TiO2- based self-cleaning materials. Photocatalytic efficiency of the as-prepared materials is crucial for commercialization; however, changes in the coating performance due to weathering become a critical factor for practical applications. Moreover, chemical durability should be considered as weathering can promote the release of photocatalyst nanoparticles, which can pollute the environment and be hazardous for human health. In this study, two photocatalytic TiO2 coatings with different microstructures (namely compact and mesoporous) were exposed to chemical treatments to simulate domestic and environmental weathering. Results show that dense TiO2 coatings with a slow photocatalytic activity are suitable for domestic applications as minimum leaching of photoactive material was observed. Conversely, once exposed to chemical solutions commonly present in domestic environments, the initially highly active mesoporous TiO2 coatings showed a dramatic drop of the selfcleaning performance and a significant release of nanoparticles in the surrounding environment. It is expected that the results reported here will be of particular relevance for the construction sector, as the manuscript discloses important knowledge for the development of TiO2-based self-cleaning materials once exposed to indoor or outdoor environments

Revisiting Delta Y/Delta Z from multiple main sequences in Globular Clusters: insight from nearby stars

For nearby K dwarfs, the broadening of the observed Main Sequence at low metallicities is much narrower than expected from isochrones with the standard helium-to-metal enrichment ratio DY/DZ=2. Though the latter value fits well the Main Sequence around solar metallicity, and agrees with independent measurements from HII regions as well as with theoretical stellar yields and chemical evolution models, a much higher DY/DZ~10 is necessary to reproduce the broadening observed for nearby subdwarfs. This result resembles, on a milder scale, the very high DY/DZ estimated from the multiple Main Sequences in Omega Cen and NGC 2808. Although not "inverted" as in omega Cen, where the metal-rich Main Sequence is bluer than the metal-poor one, the broadening observed for nearby subdwarfs is much narrower than stellar models predict for a standard helium content. We use this empirical evidence to argue that a revision of lower Main Sequence stellar models, suggested from nearby stars, could significantly reduce the helium content inferred for the subpopulations of those globular clusters. A simple formula based on empirically calibrated homology relations is constructed, for an alternative estimate of DY/DZ in multiple main sequences. We find that, under the most favourable assumptions, the estimated helium content for the enriched populations could decrease from Y~0.4 to as low as Y~0.3.Comment: 15 pages, 12 figures, in press on MNRA

Photoreceptor Activity Contributes to Contrasting Responses to Shade in Cardamine and Arabidopsis Seedlings

Plants have evolved two major ways to deal with nearby vegetation or shade: avoidance and tolerance. Moreover, some plants respond to shade in different ways; for example, Arabidopsis thaliana undergoes an avoidance response to shade produced by vegetation, but its close relative Cardamine hirsuta tolerates shade. How plants adopt opposite strategies to respond to the same environmental challenge is unknown. Here, using a genetic strategy, we identified the C. hirsuta slender in shade1 (sis1) mutants, which produce strongly elongated hypocotyls in response to shade. These mutants lack the phytochrome A (phyA) photoreceptor. Our findings suggest that C. hirsuta has evolved a highly efficient phyA-dependent pathway that suppresses hypocotyl elongation when challenged by shade from nearby vegetation. This suppression relies, at least in part, on stronger phyA activity in C. hirsuta; this is achieved by increased ChPHYA expression and protein accumulation combined with a stronger specific intrinsic repressor activity. We suggest that modulation of photoreceptor activity is a powerful mechanism in nature to achieve physiological variation (shade tolerance vs. avoidance) for species to colonize different habitats

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Predicting survival or successful bridge to heart replacement therapy in patients with acute decompensated heart failure complicated by cardiogenic shock

Background: Data from US and European registries have recently shown a changing paradigm in the epidemiology of cardiogenic shock (CS), which is shifting from a mainly post-acute myocardial infarction (AMI) syndrome to a deterioration of acute decompensated heart failure (ADHF). Since the pathophysiology of these two conditions is different, patient management becomes a real challenge for the intensivists. Notably, no dedicated score for the prediction of short-term mortality risk score has been tested in the CS-ADHF population. Purpose: 1) To evaluate the effectiveness of existing scores (SOFA: Sequential Organ Failure Assessment; SAPS II: Simplified Acute Physiology Score; inotropic and CardShock score); and 2) to derive a new score for the prediction 28-day survival in CS-ADHF patients. Methods: We retrospectively collected data on 88 consecutive patients who presented with CS-ADHF between 2009 and 2019. Multivariate logistic analysis was used to assess the association between selected independent variables and 28-day all-cause survival. c-statistic was used to evaluate the discrimination ability of the model. Results: 28-day survival was 66%. Among survived patients, 46 were treated with heart replacement therapy: 30 orthotopic heart transplantation (52%) and 16 durable left ventricle assist device (LVAD) implantation (27%). A new score (ALC – Shock) was derived based on age, serum lactates and serum creatinine (at ICU admission). ALC–Shock showed the best discrimination ability (AUC 0.8; 95% CI 0-7-0.9) compared to SOFA, SAPSII, Cardshock score and inotropic score (p = 0.009) for 28-day survival. Notably, other variables deemed clinically relevant, including cardiac power output and pulmonary artery pulsatility index, did not show a significant association with 28-day survival. Conclusions: The ALC – Shock score, which includes age, serum creatinine and lactates at ICU admission, offers a new powerful stratification tool for prediction of short-term survival in CS-ADHF patients

Studio di fattibilità per l’adesione del Consiglio Nazionale delle Ricerche al Distretto Aerospaziale Sardegna

Il Settore Spazio rappresenta, al di là degli aspetti dimensionali con circa 5.500 addetti diretti e un fatturato annuo di circa 1,4 miliardi di euro, una area di tradizionale forza ed eccellenza del sistema paese. La dimensione economica va infatti considerata alla luce del cosiddetto "effetto moltiplicatore" indotto per cui l’industria spaziale mondiale crea un indotto con un valore pari a circa 6 volte quello dell’industria stessa. Inoltre il "peso" del comparto spaziale italiano in termini di capacità di leadership su grandi programmi applicativi ovvero in aree di eccellenza espresse dalla comunità nazionale (scientifica, accademica, industriale) è certamente più rilevante rispetto alla percentuale economica del comparto nazionale rispetto al valore del mercato. Tutte considerazioni che hanno portato l'Italia ad impegnarsi nei decenni per conquistare e mantenere una posizione di leadership e di forte visibilità a livello europeo e mondiale. Obiettivo complessivo dell'Alleanza SPIN-IT (Space Innovation In Italy) è quello, alla luce del documento di visione strategica 2010-2020 della Agenzia Spaziale Italiana e dei documenti di indirizzo in ambito europeo, di contribuire ad aumentare la competitività del sistema paese attraverso una mappatura puntuale delle competenze, delle attività della filiera industriale, di ricerca e scientifiche favorendo il confronto costante tra i soggetti istituzionali interessati e catalizzando una accresciuta competitività nell’indirizzare opportunità di finanziamento della ricerca in ambito europeo