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排序方式: 共有813条查询结果,搜索用时 359 毫秒
801.
Ekta Manocha Alessandra Consonni Fulvio Baggi Emilio Ciusani Valentina Cocce Francesca Paino Carlo Tremolada Arnaldo Caruso Giulio Alessandri 《International journal of molecular sciences》2022,23(10)
Pericytes (PCs) are mesenchymal stromal cells (MSCs) that function as support cells and play a role in tissue regeneration and, in particular, vascular homeostasis. PCs promote endothelial cells (ECs) survival which is critical for vessel stabilization, maturation, and remodeling. In this study, PCs were isolated from human micro-fragmented adipose tissue (MFAT) obtained from fat lipoaspirate and were characterized as NG2+/PDGFRβ+/CD105+ cells. Here, we tested the fat-derived PCs for the dispensability of the CD146 marker with the aim of better understanding the role of these PC subpopulations on angiogenesis. Cells from both CD146-positive (CD146+) and negative (CD146−) populations were observed to interact with human umbilical vein ECs (HUVECs). In addition, fat-derived PCs were able to induce angiogenesis of ECs in spheroids assay; and conditioned medium (CM) from both PCs and fat tissue itself led to the proliferation of ECs, thereby marking their role in angiogenesis stimulation. However, we found that CD146+ cells were more responsive to PDGF-BB-stimulated migration, adhesion, and angiogenic interaction with ECs, possibly owing to their higher expression of NCAM/CD56 than the corresponding CD146− subpopulation. We conclude that in fat tissue, CD146-expressing cells may represent a more mature pericyte subpopulation that may have higher efficacy in controlling and stimulating vascular regeneration and stabilization than their CD146-negative counterpart. 相似文献
802.
803.
Emilio Scalise Michel Houssa Geoffrey Pourtois Valery Afanas’ev André Stesmans 《Nano Research》2012,5(1):43-48
The electronic properties of two-dimensional honeycomb structures of molybdenum disulfide (MoS2) subjected to biaxial strain have been investigated using first-principles calculations based on density functional theory.
On applying compressive or tensile bi-axial strain on bi-layer and mono-layer MoS2, the electronic properties are predicted to change from semiconducting to metallic. These changes present very interesting
possibilities for engineering the electronic properties of two-dimensional structures of MoS2.
相似文献
804.
Estimating biomass carbon stocks for a Mediterranean forest in central Spain using LiDAR height and intensity data 总被引:7,自引:0,他引:7
Biomass fractions (total aboveground, branches and foliage) were estimated from a small footprint discrete-return LiDAR system in an unmanaged Mediterranean forest in central Spain. Several biomass estimation models based on LiDAR height, intensity or height combined with intensity data were explored. Raw intensity data were normalized to a standard range in order to remove the range dependence of the intensity signal. In general terms, intensity-based models provided more accurate predictions of the biomass fractions. Height models selected were mainly based on a percentile of the height distribution. Intensity models selected included variables that consider the percentage of the intensity accumulated at different height percentiles, which implicitly take into account the height distribution. The general models derived considering all species together were based on height combined with intensity data. These models yielded R2 values greater than 0.58 for the different biomass fractions considered and RMSE values of 28.89, 18.28 and 1.51 Mg ha−1 for aboveground, branch and foliage biomass, respectively. Results greatly improved for species-specific models using the main species present in each plot, with R2 values greater than 0.85, 0.70 and 0.90 for black pine, Spanish juniper and Holm oak, respectively, and with lower RMSE for the biomass fractions. Reductions in LiDAR point density had only a small effect on the results obtained, except for those models based on a variation of the Canopy Reflection Sum, which was weighted by the mean point density. Based on the species-specific equations derived, Holm oak dominated plots showed the highest average carbon contained by aboveground biomass and branch biomass 44.66 and 31.42 Mg ha− 1 respectively, while for foliage biomass carbon, Spanish juniper showed the highest average value (3.04 Mg ha− 1). 相似文献
805.
Francisco Corbera Rafael Asenjo Emilio Zapata 《International journal of parallel programming》2002,30(1):37-63
Automatic parallelization of codes with complex data structures is becoming very important. These complex, and often recursive, data structures are widely used in scientific computing. Shape analysis is one of the key steps in the automatic parallelization of such codes. In this paper we extend the Static Shape Graph (SSG) method to enable the successful and accurate detection of complex doubly-linked structures. We have also included an interprocedural analysis in our framework. These techniques have been implemented in a compiler, which has been validated for several C codes. In particular, we present the results the compiler achieves for the C sparse LU factorization algorithm and for a recursive code generating a tree data structure. The output SSG perfectly describes the complex data structure used in these codes. 相似文献
806.
807.
Rubn Lpez-Corts Laura Muinelo-Romay Almudena Fernndez-Briera Emilio Gil-Martín 《International journal of molecular sciences》2022,23(15)
The present study explored the impact of inhibiting α(1,6)fucosylation (core fucosylation) on the functional phenotype of a cellular model of colorectal cancer (CRC) malignization formed by the syngeneic SW480 and SW620 CRC lines. Expression of the FUT8 gene encoding α(1,6)fucosyltransferase was inhibited in tumor line SW480 by a combination of shRNA-based antisense knockdown and Lens culinaris agglutinin (LCA) selection. LCA-resistant clones were subsequently assayed in vitro for proliferation, migration, and adhesion. The α(1,6)FT-inhibited SW480 cells showed enhanced proliferation in adherent conditions, unlike their α(1,6)FT-depleted SW620 counterparts, which displayed reduced proliferation. Under non-adherent conditions, α(1,6)FT-inhibited SW480 cells also showed greater growth capacity than their respective non-targeted control (NTC) cells. However, cell migration decreased in SW480 after FUT8 knockdown, while adhesion to EA.hy926 cells was significantly enhanced. The reported results indicate that the FUT8 knockdown strategy with subsequent selection for LCA-resistant clones was effective in greatly reducing α(1,6)FT expression in SW480 and SW620 CRC lines. In addition, α(1,6)FT impairment affected the proliferation, migration, and adhesion of α(1,6)FT-deficient clones SW480 and SW620 in a tumor stage-dependent manner, suggesting that core fucosylation has a dynamic role in the evolution of CRC. 相似文献
808.
Sara Castro-Barquero Rosa Casas Eric B. Rimm Anna Tresserra-Rimbau Dora Romaguera J. Alfredo Martínez Jordi Salas-Salvadó Miguel A. Martínez-González Josep Vidal Miguel Ruiz-Canela Jadwiga Konieczna Emilio Sacanella Jesús Francisco García-Gavilán Montse Fitó Ana García-Arellano Ramon Estruch 《Molecular nutrition & food research》2023,67(4):2200264
809.
810.
Isabel Ciria-Ramos Emilio J. Juarez-Perez Marta Haro 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(28):2301244
A Cu2O-TiO2 photoelectrode is pr+oposed for simultaneous solar light energy harvesting and storing of electrochemical energy in an adapted lithium coin cell. The p-type Cu2O semiconductor layer is the light harvester component of the photoelectrode and the TiO2 film performs as the capacitive layer. The rationale of the energy scheme shows that the photocharges generated in the Cu2O semiconductor induce lithiation/delithiation processes in the TiO2 film as a function of the applied bias voltage and light power. A photorechargeable lithium button cell drilled on one side recharges with visible white light in ≈9 h in open circuit. It provides an energy density of ≈150 mAh g−1 at 0.1 C discharge current in dark, and the overall efficiency is 0.29%. This work draws a new approach for the photoelectrode role to advance in monolithic rechargeable batteries. 相似文献