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101.
Jansa P Becvar R Ambroz D Palecek T Tomcik M Skacelova S Aschermann M Linhart A 《Clinical rheumatology》2012,31(3):557-561
Background
Systemic sclerosis (SSc) is an important cause of pulmonary arterial hypertension (PAH), with an estimated prevalence of 7.85–26.7%. 相似文献102.
Nikpay M ?eda O Tremblay J Petrovich M Gaudet D Kotchen TA Cowley AW Hamet P 《Hypertension research》2012,35(6):585-591
Links between substance use habits, obesity, stress and the related cardiovascular outcomes can be, in part, because of loci with pleiotropic effects. To investigate this hypothesis, we performed genome-wide mapping in 119 multigenerational families from a population in the Saguenay-Lac-St-Jean region with a known founder effect using 58,000 single-nucleotide polymorphisms and 437 microsatellite markers to identify genetic components of the following factors: habitual alcohol, tobacco and coffee use; response to mental and physical stress; obesity-related traits; and heart rate (HR) and blood pressure (BP) measures. Habitual alcohol and/or tobacco users had attenuated HR responses to mental stress compared with non-users, whereas hypertensive individuals had stronger HR and systolic BP responses to mental stress and a higher obesity index than normotensives. Genetic mappings uncovered numerous shared genes among substance use, stress response, obesity and hemodynamic traits, including CAMK4, CNTN4, DLG2, FHIT, GRID2, ITPR2, NOVA1 and PRKCE, forming network of interacting proteins, sharing synaptic function and display higher and patterned expression profiles in brain-related tissues; moreover, pathway analysis of shared genes pointed to long-term potentiation. Subgroup genetic mappings uncovered additional shared synaptic genes, including CAMK4, CNTN5 and DNM3 (hypertension-specific); CNTN4, DNM3, FHIT and ITPR1 (sex-specific), having protein interactions with genes driven from general analysis. In summary, consistent with the observed phenotypic correlations, we found substantial overlap among genomic determinants of these traits in synapse, which supports the notion that the neural synapse may be a shared interface behind substance use, stress, obesity, HR, BP as well as the observed sex- and hypertension-specific genetic differences. 相似文献
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A solvent-free, low-cost, high-yield and scalable single-step ball milling process is developed to construct 2D MoS2/graphene hybrid electrodes for lithium-ion batteries. Electron microscopy investigation reveals that the obtained hybrid electrodes consist of numerous nanosheets of MoS2 and graphene which are randomly distributed. The MoS2/graphene hybrid anodes exhibit excellent cycling stability with high reversible capacities (442 mA h g−1 for MoS2/graphene (40 h); 553 mA h g−1 for MoS2/graphene (20 h); 342 mA h g−1 for MoS2/graphene (10 h)) at a high current rate of 250 mA g−1 after 100 cycles, whereas the pristine MoS2 electrode shows huge capacity fading with a retention of 37 mA h g−1 at 250 mA g−1 current after 100 cycles. The incorporation of graphene into MoS2 has an extraordinary effect on its electrochemical performance. This work emphasises the importance of the construction of the 2D MoS2/graphene hybrid structure to prevent capacity fading issues with the MoS2 anode in lithium-ion batteries.A solvent-free, low-cost, high-yield and scalable single-step ball milling process is developed to construct 2D MoS2/graphene hybrid electrodes for lithium-ion batteries. 相似文献
108.
Miron Bugakov Sharifa Abdullaeva Pavel Samokhvalov Sergey Abramchuk Valery Shibaev Natalia Boiko 《RSC advances》2020,10(26):15264
Hybrid fluorescent liquid crystalline (LC) composites containing inorganic quantum dots (QDs) are promising materials for many applications in optics, nanophotonics and display technology, combining the superior emission capability of QDs with the externally controllable optical properties of LCs. In this work, we propose the hybrid LC composites that were obtained by embedding CdSe/ZnS QDs into a series of host LC block copolymers of different architectures by means of a two-stage ligand exchange procedure. The ABA/BAB triblock copolymers and AB diblock copolymers with different polymerization degrees are composed of nematogenic phenyl benzoate acrylic monomer units and poly(4-vinylpyridine) blocks, which are capable of binding to the QD surface. Our results clearly show that the spatial distribution of QDs within composite films as well as the formation of QD aggregates can be programed by varying the structure of the host block copolymer. The obtained composites form a nematic LC phase, with isotropization temperatures being close to those of the initial host block copolymers. In addition, the influence of the molecular architecture of the host block copolymers on fluorescence properties of the obtained composites is considered. The described strategy for the QD assembly should provide a robust and conventional route for the design of highly ordered hierarchical hybrid materials for many practical applications.Spatial distribution of QDs within hybrid composite films was programed by varying the molecular architecture of the host LC block copolymers. 相似文献
109.
Julia R. Shakirova Amir Sadeghi Alla A. Koblova Pavel S. Chelushkin Elisa Toropainen Shirin Tavakoli Leena-Stiina Kontturi Tatu Lajunen Sergey P. Tunik Arto Urtti 《RSC advances》2020,10(24):14431
Two iridium [Ir(N^C)2(N^N)]+ complexes with the diimine N^N ligand containing a long polymethylene hydrophobic chain were synthesized and characterized by using NMR and ESI mass-spectrometry: N^N – 2-(1-hexadecyl-1H-imidazol-2-yl)pyridine, N^C – methyl-2-phenylquinoline-4-carboxylate (Ir1) and 2-phenylquinoline-4-carboxylic acid (Ir2). These complexes were used to prepare the luminescent PEGylated DPPC liposomes (DPPC/DSPE-PEG2000/Ir-complex = 95/4.5/1 mol%) using a thin film hydration method. The narrowly dispersed liposomes had diameters of about 110 nm. The photophysics of the complexes and labeled liposomes were carefully studied. Ir1 and Ir2 give red emission (λem = 667 and 605 nm) with a lifetime in the microsecond domain and quantum yields of 4.8% and 10.0% in degassed solution. Incorporation of the complexes into the liposome lipid bilayer results in shielding of the emitters from interaction with molecular oxygen and partial suppression of excited state nonradiative relaxation due to the effect of the relatively rigid bilayer matrix. Delivery of labeled liposomes to the cultured ARPE-19 cells demonstrated the usefulness of Ir1 and Ir2 in cellular imaging. Labeled liposomes were then injected intravitreally into rat eyes and imaged successfully with optical coherence tomography and funduscopy. In conclusion, iridium complexes enabled the successful labeling and imaging of liposomes in cells and animals.Novel lipoidal Ir(iii) phosphorescent labels were embedded into liposomes and used for imaging in cells and animals. 相似文献
110.
Applicability of Raman spectroscopy for time-resolved gas composition monitoring during direct methanol synthesis via carbon dioxide hydrogenation was investigated. A series of methanol synthesis experiments with varied reactor conditions was conducted and the reactor outlet stream was analyzed with in-line gas Raman spectroscopy. Concentrations of H2, CO2 and CO were determined directly from the acquired spectral data. For evaluation of methanol and water content a data reconciliation algorithm was developed. The algorithm involves estimation of the occurring chemical reactions'' extents by iterative minimization of the difference between concentration values acquired from the experimental data and concentration values computed based on the mass conservation principle. The obtained experimental concentrations were compared and validated against the results of the reactor mathematical modeling, which is based upon a well-established kinetic interpretation of the process. The findings indicate good repeatability and accuracy of the developed gas analysis system, which together with the advantageous temporal resolution of the method, make Raman spectroscopy a promising technique for fast response monitoring of the process.Applicability of Raman spectroscopy for time-resolved gas composition monitoring during direct methanol synthesis via carbon dioxide hydrogenation is investigated. 相似文献