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Neurovascular unit on a chip:the relevance and maturity as an advanced in vitro model

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Neural Regeneration Research 2024年第6期19卷 1165-1166页

作者： Sujey Palma-Florez Anna Lagunas Mònica Mir Nanobioengineering Group Institute for Bioengineering of Catalonia(IBEC)Barcelona Institute of Science and Technology(BIST)BarcelonaSpain CIBER-BBN ISCIIIMadridSpain Department of Electronics and Biomedical Engineering University of BarcelonaBarcelonaSpain

The brain is a high-energy demanding organ,consuming around 20%of the metabolic energy *** fulfill this demand,cerebral blood flow(CBF)supplies oxygen and glucose continuously through the intricate network of cerebral blood *** for many years brain activity and blood flow were conceived as independent processes,MRI-based functional brain imaging demonstrated that there is a coupling between them.

关键词： cerebral maturity consuming

Unsupervised feature selection via multiple graph fusion and feature weight learning

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Science China(Information Sciences) 2023年第5期66卷 56-72页

作者： Chang TANG Xiao ZHENG Wei ZHANG Xinwang LIU Xinzhong ZHU En ZHU School of Computer Science China University of Geosciences State Key Laboratory for Novel Software Technology Nanjing University School of Computer National University of Defense Technology National supercomputing center in Jinan Qilu University of Technology (Shandong Academy of Sciences) College of Mathematics Physics and Information Engineering Zhejiang Normal University

Unsupervised feature selection attempts to select a small number of discriminative features from original high-dimensional data and preserve the intrinsic data structure without using data labels. As an unsupervised learning task, most previous methods often use a coefficient matrix for feature reconstruction or feature projection, and a certain similarity graph is widely utilized to regularize the intrinsic structure preservation of original data in a new feature space. However, a similarity graph with poor quality could inevitably afect the final results. In addition, designing a rational and efective feature reconstruction/projection model is not easy. In this paper, we introduce a novel and efective unsupervised feature selection method via multiple graph fusion and feature weight learning(MGF2WL) to address these issues. Instead of learning the feature coefficient matrix, we directly learn the weights of diferent feature dimensions by introducing a feature weight matrix, and the weighted features are projected into the label space. Aiming to exploit sufficient relation of data samples, we develop a graph fusion term to fuse multiple predefined similarity graphs for learning a unified similarity graph, which is then deployed to regularize the local data structure of original data in a projected label space. Finally, we design a block coordinate descent algorithm with a convergence guarantee to solve the resulting optimization problem. Extensive experiments with sufficient analyses on various datasets are conducted to validate the efficacy of our proposed MGF2WL.

关键词： unsupervised feature selection graph fusion feature weight learning local structure preservation

Phenotyping for Abiotic Stress Tolerance in Maize

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Journal of Integrative Plant Biology 2012年第4期54卷 238-249页

作者： Benhilda Masuka Jose Luis Araus Biswanath Das Kai Sonder Jill E.Cairns International Maize and Wheat Improvement center(CIMMYT) Unit of Plant Physiology Faculty of BiologyUniversity of Barcelona CIMMYT Km 45 Carretera Mexico-Veracruz

The ability to quickly develop germplasm having tolerance to several complex polygenic inherited abiotic and biotic stresses combined is critical to the resilience of cropping systems in the face of climate change. Molecular breeding offers the tools to accelerate cereal breeding; however, suitable phenotyping proto- cols are essential to ensure that the much-anticipated benefits of molecular breeding can be realized. To facilitate the full potential of molecular tools, greater emphasis needs to be given to reducing the within-experimental site variability, application of stress and characterization of the environment and appropriate phenotyping tools. Yield is a function of many processes throughout the plantcycle, and thus integrative traits that encompass crop performance over time or organization level （i.e. canopy level） will provide a better alternative to instantaneous measurements which provide only a snapshot of a given plant process. Many new phenotyping tools based on remote sensing are now available including non-destructive measurements of growth-related parameters based on spectral reflectance and infrared thermometry to estimate plant water status. Here we describe key field phenotyping protocols for maize with emphasis on tolerance to drought and low nitrogen.

关键词： Drought low nitrogen tolerance maize phenotyping spatial variability.

Human induced pluripotent stem cells derived hepatocytes:rising promise for disease modeling,drug development and cell therapy

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Protein & Cell 2012年第4期3卷 246-250页

作者： Fei Yi Guang-Hui Liu Juan Carlos Izpisua Belmonte Gene Expression Laboratory Salk Institute for Biological StudiesLa JollaCA 92037USA center for Regenerative Medicine in barcelona 08003 BarcelonaSpain National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

Recent advances in the study of human hepatocytes derived from induced pluripotent stem cells(iPSC)represent new promises for liver disease study and drug *** hepatocytes or hepatocyte-like cells differentiated from iPSC recapitulate many func-tional properties of primary human hepatocytes and have been demonstrated as a powerful and efficient tool to model human liver metabolic diseases and fa-cilitate drug development *** this review,we summarize the recent progress in this field and discuss the future perspective of the application of human iPSC derived hepatocytes.

关键词： induced pluripotent stem cells hepatocytes disease modeling drug development cell therapy

Deployment of Electric Induction Technologies into Cooktops Plates as a Part of Energy Sustainability

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Smart Grid and Renewable Energy 2022年第3期13卷 55-74页

作者： Alberto Tama International University center of barcelona (UNIBA) University of Barcelona Barcelona Spain

For a long time now, humanity has been facing the phenomenon known as “climate change”, a major challenge of which we must be aware of what we are doing so as not to affect ourselves or future generations. It is evident that, if what is sought is a sustainable energy future, the current energy model implemented in certain countries and regions of the world is not the most adequate and makes the achievement of this goal unfeasible. This situation threatens to greatly alter our ecosystems and our social structures, and one of the key actions to mitigate it is, undeniably, the generalization of the use of renewable energy sources;and specifically, the non-conventional sources, referring to solar and wind, technologies that comply with the principle of energy complementarity;however, there are other possible solutions such as the deployment of programs that consider efficient cooking technologies;involving with it is everything related to energy security and equity, as well as environmental protection. In this article, as a technology to be considered to reduce and mitigate the Greenhouse Gases (GHG) emissions, an analysis of the efficiency assessment of electric induction cooktops and the determination of their potential energy savings are carried out. The impact of these results is taken into consideration and a series of conclusions and recommendations for improvement are issued.

关键词： Energy Sustainability Sustainable Development Clean Cooking Efficient Cooking Sustainable Development Goals Energy Savings Electric Induction Cooktop

Role of aldehyde dehydrogenase 2 in ischemia reperfusion injury:An update

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World Journal of Gastroenterology 2018年第27期24卷 2984-2994页

作者： Arnau Panisello-Roselló Alexandre Lopez Emma Folch-Puy Teresa Carbonell Anabela Rolo Carlos Palmeira René Adam Marc Net Joan Roselló-Catafau Department of Experimental Pathology Institute of Biomedical Research of Barcelona(IIBB)-CSICBarcelona 08036Spain Centre Hepatobiliare AP-HP Hopital Paul BrousseVillejuif 75008France Department of Physiology Faculty of BiologyUniversitat de BarcelonaBarcelona 08036Spain center for Neuroscience and Cell Biology University of CoimbraCoimbra 3004-517Portugal Institute Georges Lopez Lissieu 69380France

Aldehyde dehydrogenase 2(ALDH2) is best known for its critical detoxifying role in liver alcohol metabolism. However, ALDH2 dysfunction is also involved in a wide range of human pathophysiological situations and is associated with complications such as cardiovascular diseases, diabetes mellitus, neurodegenerative diseases and aging. A growing body of research has shown that ALDH2 provides important protection against oxidative stress and the subsequent loading of toxic aldehydes such as 4-hydroxy-2-nonenal and adducts that occur in human diseases, including ischemia reperfusion injury(IRI). There is increasing evidence of its role in IRI pathophysiology in organs such as heart, brain, small intestine and kidney; however, surprisingly few studies have been carried out in the liver, where ALDH2 is found in abundance. This study reviews the role of ALDH2 in modulating the pathways involved in the pathophysiology of IRI associated with oxidative stress, autophagy and apoptosis. Special emphasis is placed on the role of ALDH2 in different organs, on therapeutic "preconditioning" strategies, and on the use of ALDH2 agonists such as Alda-1, which may become a useful therapeutic tool for preventing the deleterious effects of IRI in organ transplantation.

关键词： Aldehyde dehydrogenase 2 4-hydroxy-2-nonenal autophagy Apoptosis Ischemia reperfusion injury Preconditioning

Influences of Lower-Mantle Properties on the Formation of Asthenosphere in Oceanic Upper Mantle

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Journal of Earth Science 2011年第2期22卷 143-154页

作者： David A Yuen Nicola Tosi Ondrej adek Department of Geology and Geophysics and Minnesota supercomputing Institute University of MinnesotaMinneapolisMN 55415USA Department of Planetary Physics Institute of Planetary ResearchGerman Aerospace Center(DLR)BerlinGermany Department of Geophysics Faculty of Mathematics and PhysicsCharles UniversityPragueCzech Republic

Asthenosphere is a venerable concept based on geological intuition of Reginald Daly nearly 100 years ago. There have been various explanations for the existence of the asthenosphere. The concept of a plume-fed asthenosphere has been around for a few years due to the ideas put forth by Yamamoto et al.. Using a two-dimensional Cartesian code based on finite-volume method, we have investigated the influences of lower-mantle physical properties on the formation of a low-viscosity zone in the oceanic upper mantle in regions close to a large mantle upwelUng. The rheological law is Newtonian and depends on both temperature and depth. An extended-Boussinesq model is assumed for the energetics and the olivine to spinel, the spinel to perovskite and perovskite to post-perovskite （ppv） phase transitions are considered. We have compared the differences in the behavior of hot upweilings passing through the transition zone in the mid-mantle for a variety of models, starting with constant physical properties in the lower-mantle and culminating with complex models which have the post-perovskite phase transition and depth-dependent coefficient of thermal expansion and thermal conductivity. We found that the formation of the asthenosphere in the upper mantle in the vicinity of large upwellings is facilitated in models where both depth-dependent thermal expansivity and conductivity are included. Models with constant thermal expansivity and thermal conductivity do not produce a hot low-viscosity zone, resembling the asthenosphere. We have also studied the influences of a cylindrical model and found similar results as the Cartesian model with the important difference that upper-mantle temperatures were much cooler than the Cartesian model by about 600 to 700 K. Our findings argue for the potentially important role played by lower-mantle material properties on the development of a plume-fed asthenosphere in the oceanic upper mantle.

关键词： oceanic asthenosphere lower mantle thermal expansivity thermal conductivity phase transition.

Long-term in vivo single-cell lineage tracing of deep structures using three-photon activation

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Light(Science & Applications) 2016年第1期5卷 730-736页

作者： Isil Tekeli Isabelle Aujard Xavier Trepat Ludovic Jullien Angel Raya Dobryna Zalvidea center of Regenerative Medicine in barcelona(CMRB) Barcelona Biomedical Research ParkDr Aiguader 8808003 BarcelonaSpain Control of Stem Cell Potency Group Institute for Bioengineering of Catalonia(IBEC)Barcelona Science ParkBaldiri Reixac 15-2108028 BarcelonaSpain École Normale Supérieure-PSL Research University Department of Chemistry24 rue LhomondF-75005 ParisFrance Sorbonne Universités UPMC Univ Paris 06PASTEURF-75005 ParisFrance CNRS UMR 8640 PASTEURF-75005 ParisFrance Integrative Cell and Tissue Dynamics Group Institute of Bioengineering of Catalonia(IBEC)08028 BarcelonaSpain InstitucióCatalana de Recerca i Estudis Avançats(ICREA) 08010 BarcelonaSpain center for Networked Biomedical Research on Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)28029 MadridSpain

Genetic labeling techniques allow for noninvasive lineage tracing of cells in ***-photon inducible activators provide spatial resolution for superficial cells,but labeling cells located deep within tissues is precluded by scattering of the far-red illumination required for two-photon ***-photon illumination has been shown to overcome the limitations of two-photon microscopy for in vivo imaging of deep structures,but whether it can be used for photoactivation remains to be *** we show,both theoretically and experimentally,that three-photon illumination overcomes scattering problems by combining longer wavelength excitation with high uncaging three-photon cross-section *** prospectively labeled heart muscle cells in zebrafish embryos and found permanent labeling in their progeny in adult animals with negligible tissue *** technique allows for a noninvasive genetic manipulation in vivo with spatial,temporal and cell-type specificity,and may have wide applicability in experimental biology.

关键词： multi-photon microscopy photoactivation three-photon microscopy zebrafish

Unimolecular Reactions of E-Glycolaldehyde Oxide and Its Reactions with One and Two Water Molecules

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Research 2024年第1期2023卷 809-824页

作者： Yan Sun Bo Long Donald G.Truhlar Department of Physics Guizhou UniversityGuiyang 550025China College of Materials Science and Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Chemistry Chemical Theory Centerand Supercomputing InstituteUniversity of MinnesotaMinneapolisMN 55455-0431USA

The kinetics of Criegee intermediates are important for atmospheric ***,the quantitative kinetics of Criegee intermediates are still very limited,especially for those with hydroxy ***,we calculate rate constants for the unimolecular reaction of E-glycolaldehyde oxide[E-hydroxyethanal oxide,E-(CH_(2)OH)CHOO],for its reactions with H_(2)O and(H_(2)O)_(2),and for the reaction of the E-(CH_(2)OH)CHOO…H_(2)O complex with H_(2)*** the highest level of electronic structure,we use W3X-L//CCSD(T)-F12a/cc-pVDZ-F12 for the unimolecular reaction and the reaction with water and W3X-L//DF-CCSD(T)-F12b/jun-cc-pVDZ for the reaction with 2 water *** the dynamics,we use a dual-level strategy that combines conventional transition state theory with the highest level of electronic structure and multistructural canonical variational transition state theory with small-curvature tunneling with a validated density functional for the electronic structure.

关键词： structure kinetics molecular