Produção orgânica de diferentes cultivares de morangueiro cultivados em solo coberto com acículas de pínus e plástico preto na região de Chapecó, SC.

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Evaluation of the role of carbon nanotubes on the electrical properties of poly(butylene-terephthalate) nanocomposites for industrial applications

In this article, innovative electrically conductive polymer nanocomposites based on poly(butylene terephthalate) (PBT) filled with carbon nanotubes (CNTs) at different concentrations, to be used in the automotive field, have been investigated. Field emission scanning electron microscopy (FESEM) analysis revealed how a good nanofiller dispersion was obtained, especially by using surface treated nanotubes and by processing these materials using a more restrictive screw configuration. Melt flow index measurements highlighted that the processability of these nanocomposites was reduced at elevated filler amounts, even if CNT surface treatment promoted a partial retention of the fluidity of the neat PBT. Thermal degradation stability was improved upon the addition of CNT, even at limited filler amounts. Differential scanning calorimetry measurements evidenced how the presence of CNT slightly increased both the crystallization temperature and the crystalline fraction of the materials. The additivation of CNTs promoted a stiffening effect at elevated CNT contents, associated to an evident embrittlement of the samples. Electrical resistivity measurements showed that the most interesting results (i.e. 2.6 101 Ocm) were obtained for nanocomposites with a total filler content of 3 wt%, processed using the more restrictive screw configuration. For these materials, it was possible to obtain a rapid surface heating through Joule effect at applied voltages of 12 V.The authors gratefully acknowledge Minlargilih Melak Amare for his collaboration in the experimental activities. The authors also acknowledge the Portuguese Foundation for Science and Technology (FCT) for project PEst-C/CTM/LA0025/2013 (LA 25—2015–2017). This research activity has been supported by Fondazione Cassa di Risparmio di Trento e Rovereto (CARITRO) within the project “Bando Caritro 2014 per progetti di ricerca scientifica finalizzati allo sviluppo di iniziative imprenditoriali.” The work was also supported by the National Interuniversitary Consortium of Materials Science and Technology (INSTM)

Influence of warming and atmospheric circulation changes on multidecadal European flood variability

International audienceEuropean flood frequency and intensity change on a multidecadal scale. Floods were more frequent in the 19th (central Europe) and early 20th century (western Europe) than during the mid-20th century and again more frequent since the 1970s. The causes of this variability are not well understood and the relation to climate change is unclear. Palaeoclimate studies from the northern Alps suggest that past flood-rich periods coincided with cold periods. In contrast, some studies suggest that more floods might occur in a future, warming world. Here we address the contribution of atmospheric circulation and of warming to multidecadal flood variability. For this, we use long series of annual peak streamflow, daily weather data, reanalyses, and reconstructions. We show that both changes in atmospheric circulation and moisture content affected multidecadal changes of annual peak streamflow in central and western Europe over the past two centuries. We find that during the 19th and early 20th century, atmospheric circulation changes led to high peak values of moisture flux convergence. The circulation was more conducive to strong and long-lasting precipitation events than in the mid-20th century. These changes are also partly reflected in the seasonal mean circulation and reproduced in atmospheric model simulations, pointing to a possible role of oceanic variability. For the period after 1980, increasing moisture content in a warming atmosphere led to extremely high moisture flux convergence. Thus, the main atmospheric driver of flood variability changed from atmospheric circulation variability to water vapour increase.La fréquence et l'intensité des inondations en Europe changent à une échelle multidécennale. Les inondations étaient plus fréquentes au 19ème (Europe centrale) et au début du 20ème siècle (Europe occidentale) qu'au milieu du 20ème siècle et à nouveau plus fréquentes depuis les années 1970. Les causes de cette variabilité ne sont pas bien comprises et la relation avec le changement climatique n'est pas claire. Les études paléoclimatiques menées dans les Alpes du Nord suggèrent que les périodes passées riches en inondations coïncidaient avec des périodes froides. En revanche, certaines études suggèrent que davantage d'inondations pourraient se produire dans un monde futur en réchauffement. Nous abordons ici la contribution de la circulation atmosphérique et du réchauffement à la variabilité multidécennale des inondations. Pour cela, nous utilisons de longues séries de débit maximal annuel, des données météorologiques quotidiennes, des réanalyses et des reconstructions climatiques. Nous montrons que les changements de la circulation atmosphérique et du contenu en humidité ont affecté les changements multidécennaux du débit maximal annuel en Europe centrale et occidentale au cours des deux derniers siècles. Nous constatons qu'au cours du 19ème et du début du 20ème siècle, les changements de la circulation atmosphérique ont conduit à des valeurs de pointe élevées de convergence du flux d'humidité. La circulation était plus propice à des événements de précipitations forts et durables qu'au milieu du 20e siècle. Ces changements se reflètent également en partie dans la circulation moyenne saisonnière et sont reproduits dans les simulations des modèles atmosphériques, ce qui indique un rôle possible de la variabilité océanique. Pour la période après 1980, l'augmentation de la teneur en humidité dans une atmosphère qui se réchauffe a conduit à une convergence extrêmement élevée des flux d'humidité. Ainsi, le principal moteur atmosphérique de la variabilité des crues est passé de la variabilité de la circulation atmosphérique à l'augmentation de la vapeur d'eau

Oxidative damage and erythrocyte membrane transport abnormalities in thalassemias

Oxidative damage induced by free globin chains has been implicated in the pathogenesis of the membrane abnormalities observed in alpha and beta thalassemia. We have evaluated transport of Na+ and K+ in erythrocytes of patients with thalassemias as well as in two experimental models that use normal human red blood cells, one for alpha thalassemia (methylhydrazine treatment, alpha thalassemia like) and one for beta thalassemia (phenylhydrazine treatment, beta thalassemia like). With the exception of the Na-K pump, similar alterations in membrane transport were observed in thalassemia and thalassemia-like erythrocytes. These were: increased K-Cl cotransport, Na-Li countertransport and reduced Na-K-Cl cotransport. The Na-K pump was reduced in thalassemia-like cells, whereas it was increased in severe alpha thalassemia and in beta thalassemia cells. The increased K-Cl cotransport activity could be observed in light and dense fractions of beta-thalassemic cells. K-Cl cotransport in thalassemic and thalassemia-like erythrocytes was partially inhibited by [(dihydro-indenyl) oxy] alkanoic acid and completely abolished by dithiothreitol. Thus, oxidative damage represents an important factor in the increased activity of the K-Cl cotransport observed in thalassemias, and of the K+ loss observed in beta-thalassemia erythrocytes

Morango.

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How Covid-19 changed the epidemiology of febrile urinary tract infections in children in the emergency department during the first outbreak

Background: The first Covid-19 pandemic affected the epidemiology of several diseases. A general reduction in the emergency department (ED) accesses was observed during this period, both in adult and pediatric contexts. Methods: This retrospective study was conducted on the behalf of the Italian Society of Pediatric Nephrology (SINePe) in 17 Italian pediatric EDs in March and April 2020, comparing them with data from the same periods in 2018 and 2019. The total number of pediatric (age 0–18 years) ED visits, the number of febrile urinary tract infection (UTI) diagnoses, and clinical and laboratory parameters were retrospectively collected. Results: The total number of febrile UTI diagnoses was 339 (73 in 2020, 140 in 2019, and 126 in 2018). During the first Covid-19 pandemic, the total number of ED visits decreased by 75.1%, the total number of febrile UTI diagnoses by 45.1%, with an increase in the UTI diagnosis rate (+ 121.7%). The data collected revealed an increased rate of patients with two or more days of fever before admission (p = 0.02), a significant increase in hospitalization rate (+ 17.5%, p = 0.008) and also in values of C reactive protein (CRP) (p = 0.006). In 2020, intravenous antibiotics use was significantly higher than in 2018 and 2019 (+ 15%, p = 0.025). Urine cultures showed higher Pseudomonas aeruginosa and Enterococcus faecalis percentages and lower rates of Escherichia coli (p = 0.02). Conclusions: The first wave of the Covid-19 pandemic had an essential impact on managing febrile UTIs in the ED, causing an absolute reduction of cases referring to the ED but with higher clinical severity. Children with febrile UTI were more severely ill than the previous two years, probably due to delayed access caused by the fear of potential hospital-acquired Sars-Cov-2 infection. The possible increase in consequent kidney scarring in this population should be considered

The pyruvate kinase activator mitapivat reduces hemolysis and improves anemia in a \u3b2-thalassemia mouse model

Anemia in \u3b2-thalassemia is related to ineffective erythropoiesis and reduced red cell survival. Excess free heme and accumulation of unpaired \u3b1-globin chains impose substantial oxidative stress on \u3b2-thalassemic erythroblasts and erythrocytes, impacting cell metabolism. We hypothesized that increased pyruvate kinase activity induced by mitapivat (AG-348) in the Hbbth3/+ mouse model for \u3b2-thalassemia would reduce chronic hemolysis and ineffective erythropoiesis through stimulation of red cell glycolytic metabolism. Oral mitapivat administration ameliorated ineffective erythropoiesis and anemia in Hbbth3/+ mice. Increased ATP, reduced reactive oxygen species production, and reduced markers of mitochondrial dysfunction associated with improved mitochondrial clearance suggested enhanced metabolism following mitapivat administration in \u3b2-thalassemia. The amelioration of responsiveness to erythropoietin resulted in reduced soluble erythroferrone, increased liver Hamp expression, and diminished liver iron overload. Mitapivat reduced duodenal Dmt1 expression potentially by activating the pyruvate kinase M2-HIF2\u3b1 axis, representing a mechanism additional to Hamp in controlling iron absorption and preventing \u3b2-thalassemia\u2013related liver iron overload. In ex vivo studies on erythroid precursors from patients with \u3b2-thalassemia, mitapivat enhanced erythropoiesis, promoted erythroid maturation, and decreased apoptosis. Overall, pyruvate kinase activation as a treatment modality for \u3b2-thalassemia in preclinical model systems had multiple beneficial effects in the erythropoietic compartment and beyond, providing a strong scientific basis for further clinical trials

Missense mutations in the ABVB6 transporter cause dominat familial pseudohyperkaliemia

Familial Pseudohyperkalemia (FP) is a dominant red cell trait characterized by increased serum [K1] inwhole blood stored at or below room temperature, without additional hematological abnormalities. Functionalgene mapping and sequencing analysis of the candidate genes within the 2q35–q36 critical intervalidentified—in 20 affected individuals among three multigenerational FP families—two novel heterozygousmissense mutations in the ABCB6 gene that cosegregated with disease phenotype. The two genomic substitutionsaltered two adjacent nucleotides within codon 375 of ABCB6, a porphyrin transporter that, inerythrocyte membranes, bears the Langereis blood group antigen system. The ABCB6 R375Q mutation didnot alter the levels of mRNA or protein, or protein localization in mature erythrocytes or erythroid precursorcells, but it is predicted to modestly alter protein structure. ABCB6 mRNA and protein levels increase duringin vitro erythroid differentiation of CD341 erythroid precursors and the erythroleukemia cell lines HELand K562. These data suggest that the two missense mutations in residue 375 of the ABCB6 polypeptidefound in affected individuals of families with chromosome 2-linked FP could contribute to the red cell K1leak characteristic of this condition

Calpain-1 knockout reveals broad effects on erythrocyte deformability and physiology

Pharmacological inhibitors of cysteine proteases have provideduseful insights into the regulation of calpain activity inerythrocytes. However, the precise biological function of calpainactivity in erythrocytes remains poorly understood. Erythrocytesexpress calpain-1, an isoform regulated by calpastatin, theendogenous inhibitor of calpains. In the present study, weinvestigated the function of calpain-1 in mature erythrocytes usingour calpain-1-null [KO (knockout)] mouse model. The calpain-1gene deletion results in improved erythrocyte deformabilitywithout any measurable effect on erythrocyte lifespan in vivo.The calcium-induced sphero-echinocyte shape transition iscompromised in the KO erythrocytes. Erythrocyte membraneproteins ankyrin, band 3, protein 4.1R, adducin and dematin aredegraded in the calcium-loaded normal erythrocytes but not inthe KO erythrocytes. In contrast, the integrity of spectrin andits state of phosphorylation are not affected in the calciumloadederythrocytes of either genotype. To assess the functionalconsequences of attenuated cytoskeletal remodelling in the KOerythrocytes, the activity of major membrane transporters wasmeasured. The activity of the K+\u2013Cl 12 co-transporter and theGardos channel was significantly reduced in the KO erythrocytes.Similarly, the basal activity of the calcium pump was reducedin the absence of calmodulin in the KO erythrocyte membrane.Interestingly, the calmodulin-stimulated calcium pump activitywas significantly elevated in the KO erythrocytes, implying awider range of pump regulation by calcium and calmodulin. Takentogether, and with the atomic force microscopy of the skeletalnetwork, the results of the present study provide the first evidencefor the physiological function of calpain-1 in erythrocytes withtherapeutic implications for calcium imbalance pathologies suchas sickle cell disease