1,062 research outputs found

    A new spin-anisotropic harmonic honeycomb iridate

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    The physics of Mott insulators underlies diverse phenomena ranging from high temperature superconductivity to exotic magnetism. Although both the electron spin and the structure of the local orbitals play a key role in this physics, in most systems these are connected only indirectly --- via the Pauli exclusion principle and the Coulomb interaction. Iridium-based oxides (iridates) open a further dimension to this problem by introducing strong spin-orbit interactions, such that the Mott physics has a strong orbital character. In the layered honeycomb iridates this is thought to generate highly spin-anisotropic interactions, coupling the spin orientation to a given spatial direction of exchange and leading to strongly frustrated magnetism. The potential for new physics emerging from such interactions has driven much scientific excitement, most recently in the search for a new quantum spin liquid, first discussed by Kitaev \cite{kitaev_anyons_2006}. Here we report a new iridate structure that has the same local connectivity as the layered honeycomb, but in a three-dimensional framework. The temperature dependence of the magnetic susceptibility exhibits a striking reordering of the magnetic anisotropy, giving evidence for highly spin-anisotropic exchange interactions. Furthermore, the basic structural units of this material suggest the possibility of a new family of structures, the `harmonic honeycomb' iridates. This compound thus provides a unique and exciting glimpse into the physics of a new class of strongly spin-orbit coupled Mott insulators.Comment: 12 pages including bibliography, 5 figure

    Filogenia do gĂȘnero Spondias com base em marcadores RAPD resultados preliminares.

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    O trabalho teve como objetivo, estudar as relaçÔes de ancestralidade (filogenia) entre as diferentes Spondias visando agrupar as espécies/híbridos com base em marcadores de DNA do tipo RAPD

    A HPLC‐DAD method for identifying and estimating the content of fucoxanthin, ÎČ‐carotene and chlorophyll a in brown algal extracts

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    Seaweeds are photosynthetic organisms that have high contents of pigments. The coloration of each alga is defined by the content and combination of pigments synthesized, which varies among species and environmental conditions. The most abundant pigments in algae are chlorophylls and carotenoids, lipophilic molecules that can be used as natural colorants and have high acceptance by consumers. In this work, a simple and short hands-on time HPLC-DAD method for identifying and estimating the pigment content of algal extracts, specifically fucoxanthin, ÎČ-carotene and chlorophyll a was carried out. Using this optimized method, a pigment screening was performed on the ethanolic extracts obtained by ultrasound-assisted extraction from nine brown algal from the Atlantic coastline: Ascophyllum nodosum, Bifurcaria bifurcata, Fucus spiralis, Himanthalia elongata, Laminaria saccharina, Laminaria ochroleuca, Pelvetia canaliculata, Sargassum muticum and Undaria pinnatifida. HPLC results permitted to highlight L. saccharina and U. pinnatifida as promising sources of these three target pigments containing a total amount of 10.5 – 11.5 mg per gram of dry weight. Among them, the most abundant one was fucoxanthin, an added-value compound with a high potential to be commercially exploited by different industries, such as the food, cosmetic, and pharmaceutical sectors.The research leading to these results was supported by MICINN sup- porting the RamĂłn y Cajal grant for M.A. Prieto (RYC-2017-22891), the FPU grant for A. Carreira-Casais (FPU2016/06135); and by Xunta de Galicia for supporting the post-doctoral grant of M. Fraga-Corral (ED481B-2019/096). The research leading to these results was sup- ported by the European Union through the “NextGenerationEU ”pro- gram supporting the “Margarita Salas ”grant awarded to P. Garcia- Perez. Authors are grateful to AlgaMar company ( www.algamar.com ) for the collaboration and algal material provision. This research was funded by the Ibero-American Program on Science and Technology (CYTED —AQUA-CIBUS, P317RT0003), the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of C. Lourenço- Lopes. The JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consor- tium. The project SYSTEMIC Knowledge hub on Nutrition and Food Se- curity, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint ac- tion of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 un- der the ERA-NET ERA-HDHL (n°696295). The authors would like to thank the EU and FCT for funding through the project PTDC/OCE- ETA/30240/2017- SilverBrain - From sea to brain: Green neuropro- tective extracts for nanoencapsulation and functional food production (POCI-01-0145-FEDER-030240).info:eu-repo/semantics/publishedVersio

    Aquaculture as a circular bio-economy model with Galicia as a study case: How to transform waste into revalorized by-products

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    Background: World-wide aquaculture represents a very important sector capable of supplying huge amounts of animal protein. However its relevance has proportionally augmented its waste generation. In Europe, the geographical constitution of Galicia has prompted the instauration of many aquaculture-based systems along its coasts. Indeed aquaculture means a very relevant industry in Galicia, together with animal farming, agriculture and biotechnology. Scope and approach: Over the last decade Europe legislation encourages the proper management of wastes (mostly reutilization and reducing strategies) and the sustainable use of natural resources. The application of circular bio-economy (reuse of wastes) represents a feasible model to protect human and animal health and the environment. To achieve a more efficient production system that complies with European regulations, aquaculture wastes and sub-products need to be re-utilised to increase their throughput. This approach will positively impact on their economical yield while reducing their generation and thus protecting health and environment. Key findings and conclusions: Different applications have been considered for re-using aquaculture wastes and sub-products. One of the most efficient approaches is the establishment of models that allow the metabolic waste reduction, as the integrated multi-trophic aquaculture. For derived aquaculture sub-products, the most efficient process is recovering important biomolecules such as proteins (collagen, gelatine), polysaccharides (chitosan), lipids (omega 3) or pigments (astaxanthin or beta-carotene). Biomolecules can further be applied for human and animal consumption, food industry, cosmetics or pharmaceuticals. Due to the importance of this productive system in Galicia it is critical its update to include aquaculture into circular bio-economy.The research leading to these results received institutional and financial support from: Programa de CooperaciÂŽon Interreg V-A España—Portugal (POCTEP) 2014–2020 (projects Ref.: 0181_NANOEATERS_01_E and Ref: 0377_IBERPHENOL_6_E); Spanish Ministry of Economy, Industry and Competitiveness through the project AGL2015–67039–C3–1–R; MICINN supporting the RamÂŽon&Cajal grant for M.A. Prieto (RYC-2017-22891); Xunta de Galicia and University of Vigo for supporting the post-doctoral grant of MarĂ­a Fraga Corral (ED481B-2019/096) and the pre-doctoral grants of AntĂ­a GonzÂŽalez Pereira (ED481A-2019/0228) and P. GarcĂ­a-Oliveira (ED481A-2019/ 295); Xunta de Galicia through the program EXCELENCIA-ED431F 2020/12 and the project ED431B 2019/24; Ibero-American Program on Science and Technology (CYTED - AQUA-CIBUS, P317RT0003); Axudas Conecta Peme (Xunta de Galicia) supporting the IN852A 2018/ 58 NeuroFood Project; AlgaMar (www.algamar.com); EcoChestnut Project (Erasmus+ KA202); Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBIJTI- 2019), the JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. Funding for open access charge: Universidade de Vigo/ CISUG.info:eu-repo/semantics/publishedVersio

    Biodiesel Production From Lignocellulosic Biomass Using Oleaginous Microbes: Prospects for Integrated Biofuel Production

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    Biodiesel is an eco-friendly, renewable, and potential liquid biofuel mitigating greenhouse gas emissions. Biodiesel has been produced initially from vegetable oils, non-edible oils, and waste oils. However, these feedstocks have several disadvantages such as requirement of land and labor and remain expensive. Similarly, in reference to waste oils, the feedstock content is succinct in supply and unable to meet the demand. Recent studies demonstrated utilization of lignocellulosic substrates for biodiesel production using oleaginous microorganisms. These microbes accumulate higher lipid content under stress conditions, whose lipid composition is similar to vegetable oils. In this paper, feedstocks used for biodiesel production such as vegetable oils, non-edible oils, oleaginous microalgae, fungi, yeast, and bacteria have been illustrated. Thereafter, steps enumerated in biodiesel production from lignocellulosic substrates through pretreatment, saccharification and oleaginous microbe-mediated fermentation, lipid extraction, transesterification, and purification of biodiesel are discussed. Besides, the importance of metabolic engineering in ensuring biofuels and biorefinery and a brief note on integration of liquid biofuels have been included that have significant importance in terms of circular economy aspects.Fil: Chintagunta, Anjani Devi. Vignan’s Foundation for Science, Technology and Research. Department of Biotechnology; IndiaFil: Zuccaro, Gaetano. Institut National de la Recherche Agronomique; Francia. UniversitĂ  degli Studi di Napoli Federico II; ItaliaFil: Kumar, Mahesh. Central Agricultural University; IndiaFil: Kumar, S. P. Jeevan. Indian Institute of Seed Science; India. Directorate of Floricultural Research; IndiaFil: Garlapati, Vijay Kumar. Jaypee University of Information Technology; IndiaFil: Postemsky, Pablo Daniel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Centro de Recursos Naturales Renovables de la Zona SemiĂĄrida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona SemiĂĄrida; ArgentinaFil: Kumar, N. S. Sampath. Vignan’s Foundation for Science, Technology and Research. Department of Biotechnology; IndiaFil: Chandel, Anuj K.. Universidade de Sao Paulo; BrasilFil: Simal Gandara, Jesus. Universidad de Vigo; Españ

    NADPH Oxidase 5 Is a Pro‐Contractile Nox Isoform and a Point of Cross‐Talk for Calcium and Redox Signaling‐Implications in Vascular Function

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    Background NADPH Oxidase 5 (Nox5) is a calcium‐sensitive superoxide‐generating Nox. It is present in lower forms and higher mammals, but not in rodents. Nox5 is expressed in vascular cells, but the functional significance remains elusive. Given that contraction is controlled by calcium and reactive oxygen species, both associated with Nox5, we questioned the role of Nox5 in pro‐contractile signaling and vascular function. Methods and Results Transgenic mice expressing human Nox5 in a vascular smooth muscle cell–specific manner (Nox5 mice) and Rhodnius prolixus, an arthropod model that expresses Nox5 endogenoulsy, were studied. Reactive oxygen species generation was increased systemically and in the vasculature and heart in Nox5 mice. In Nox5‐expressing mice, agonist‐induced vasoconstriction was exaggerated and endothelium‐dependent vasorelaxation was impaired. Vascular structural and mechanical properties were not influenced by Nox5. Vascular contractile responses in Nox5 mice were normalized by N‐acetylcysteine and inhibitors of calcium channels, calmodulin, and endoplasmic reticulum ryanodine receptors, but not by GKT137831 (Nox1/4 inhibitor). At the cellular level, vascular changes in Nox5 mice were associated with increased vascular smooth muscle cell [Ca2+]i, increased reactive oxygen species and nitrotyrosine levels, and hyperphosphorylation of pro‐contractile signaling molecules MLC20 (myosin light chain 20) and MYPT1 (myosin phosphatase target subunit 1). Blood pressure was similar in wild‐type and Nox5 mice. Nox5 did not amplify angiotensin II effects. In R. prolixus, gastrointestinal smooth muscle contraction was blunted by Nox5 silencing, but not by VAS2870 (Nox1/2/4 inhibitor). Conclusions Nox5 is a pro‐contractile Nox isoform important in redox‐sensitive contraction. This involves calcium‐calmodulin and endoplasmic reticulum–regulated mechanisms. Our findings define a novel function for vascular Nox5, linking calcium and reactive oxygen species to the pro‐contractile molecular machinery in vascular smooth muscle cells

    1281O Atezolizumab (atezo) vs platinum-based chemo in blood-based tumour mutational burden-positive (bTMB+) patients (pts) with first-line (1L) advanced/metastatic (m)NSCLC: Results of the Blood First Assay Screening Trial (BFAST) phase III cohort C

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    Background: TMB is a promising biomarker for immunotherapy in NSCLC, but current data are mostly retrospective. As not all pts may have sufficient tissue for comprehensive biomarker testing, bTMB was prospectively tested as a novel biomarker using targeted next-generation sequencing. BFAST (NCT03178552), a global, open-label, multi-cohort trial, evaluated safety and efficacy of targeted therapies or immunotherapy in biomarker-selected pts with unresectable mNSCLC. Here we present results from Cohort C of 1L atezo vs platinum-based chemo in pts with bTMB+ mNSCLC. Methods: We planned to randomise ≈440 pts with 1L mNSCLC with measurable disease per RECIST 1.1 and bTMB ≄10 (9.1 mut/Mb; FMI bTMB assay) 1:1 to atezo 1200 mg IV every 3 weeks or chemo and stratified by tissue availability, ECOG PS, bTMB and histology. The primary endpoint was INV-PFS per RECIST 1.1 in bTMB ≄16 (14.5 mut/Mb) pts. Key secondary endpoints included OS in bTMB ≄10 (intent to treat, ITT) and bTMB ≄16 pts, and INV-PFS in ITT pts. Results: 471 pts were assigned to atezo (n=234) or chemo (n=237). At baseline, 72% had non-squamous histology, 2% never smoked and median SLD was 103 mm. 145 pts with bTMB ≄16 were assigned to atezo and 146 to chemo. At data cutoff (21 May 2020) minimum follow up was 6 mo. INV-PFS difference in bTMB ≄16 pts for atezo vs chemo was not significant (P=0.053; Table). Grade 3-4 TRAEs occurred in 18% (atezo) vs 46% (chemo) of pts. Serious TRAEs occurred in 12% (atezo) vs 14% (chemo). Results at other bTMB thresholds and by F1L CDx will also be presented as an exploratory analysis. Conclusions: The primary PFS endpoint in bTMB ≄16 pts was not met. OS was numerically better with atezo vs chemo but the difference was not statistically significant. The safety profile of atezo vs chemo was favourable and consistent with atezo monotherapy across indications
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