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101.
102.
Cintia Ocampo Ramon Oliver Elaine Armelin Carlos Alemán Francesc Estrany 《Journal of Polymer Research》2006,13(3):193-200
Electrodeposition of poly(3,4-ethylenedioxythiophene) by electrochemical polymerization of 3,4-ethylenedioxythiophene has
been performed on steel electrodes rather than on the typically used inert electrodes (Pt, Au, graphite carbon). The polymer
was generated by cyclic voltammetry, chronopotentiometry and chronoamperometry from a 10 mM monomer solution in acetonitrile
with 0.1 M LiClO4. Elemental analysis of the generated polymer indicated that the monomeric units support 0.54 positive charges balanced with
CIO4
14− counterions. Electrochemical, electrical and structural properties of the prepared material have been characterized. The
good adherence of films combined with its excellent properties indicate that poly(3,4-ethylenedioxythiophene) can be a suitable
material for anticorrosion applications. 相似文献
103.
Dr. Ignacio Delso Dr. Jessika Valero‐Gonzalez Dr. Fernando Gomollón‐Bel Jorge Castro‐López Dr. Wenxia Fang Dr. Iva Navratilova Prof. Daan M. F. van Aalten Prof. Tomás Tejero Prof. Pedro Merino Dr. Ramon Hurtado‐Guerrero 《ChemMedChem》2018,13(2):128-132
Fungal β‐1,3‐glucan glucanosyltransferases are glucan‐remodeling enzymes that play important roles in cell wall integrity, and are essential for the viability of pathogenic fungi and yeasts. As such, they are considered possible drug targets, although inhibitors of this class of enzymes have not yet been reported. Herein we report a multidisciplinary approach based on a structure‐guided design using a highly conserved transglycosylase from Sacharomyces cerevisiae, that leads to carbohydrate derivatives with high affinity for Aspergillus fumigatus Gel4. We demonstrate by X‐ray crystallography that the compounds bind in the active site of Gas2/Gel4 and interact with the catalytic machinery. The topological analysis of noncovalent interactions demonstrates that the combination of a triazole with positively charged aromatic moieties are important for optimal interactions with Gas2/Gel4 through unusual pyridinium cation–π and face‐to‐face π–π interactions. The lead compound is capable of inhibiting AfGel4 with an IC50 value of 42 μm . 相似文献
104.
A tree‐based algorithm for virtual infrastructure allocation with joint virtual machine and network requirements 下载免费PDF全文
Ramon de Oliveira Guilherme Piegas Koslovski 《International Journal of Network Management》2017,27(1)
Cloud providers have introduced the on‐demand provisioning of virtual infrastructures (VIs) to deliver virtual networks of computing resources as a service. By combining network and computing virtualization, providers allow traffic isolation between hosted VIs. Taking advantage of this opportunity, tenants have deployed private VIs with application‐optimized network topologies to increase quality of experience of final users. One of the main open challenges in this scenario is the allocation of physical resources to host VIs in accordance with quality of service computing (eg, virtual CPUs and memory) and network requirements (guaranteed bandwidth and specific network topology). Moreover, a VI can be allocated anywhere atop a network datacenter, and because of its NP‐hard complexity, the search for optimal solutions has a limited applicability in cloud providers as requesting users seek an immediate response. The present work proposes an algorithm to accomplish the VI allocation by applying tree‐based heuristics to reduce the search space, performing a joint allocation of computing and network resources. So as to accomplish this goal, the mechanism includes a strategy to convert physical and virtual graphs to trees, which later are pruned by a grouped accounting algorithm. These innovations reduce the number of comparisons required to allocate a VI. Experimental results indicate that the proposed algorithm finds an allocation on feasible time for different cloud scenarios and VI topologies, while maintaining a high acceptance rate and a moderate physical infrastructure fragmentation. 相似文献
105.
Cover Picture: Stabilization of Telomeric I‐Motif Structures by (2′S)‐2′‐Deoxy‐2′‐C‐Methylcytidine Residues (ChemBioChem 12/2017) 下载免费PDF全文
106.
Stabilization of Telomeric I‐Motif Structures by (2′S)‐2′‐Deoxy‐2′‐C‐Methylcytidine Residues 下载免费PDF全文
Dr. Anna Aviñó María Dellafiore Dr. Raimundo Gargallo Prof. Dr. Carlos González Dr. Adolfo M. Iribarren Dr. Javier Montserrat Prof. Dr. Ramon Eritja 《Chembiochem : a European journal of chemical biology》2017,18(12):1123-1128
G‐quadruplexes and i‐motifs are tetraplex structures present in telomeres and the promoter regions of oncogenes. The possibility of producing nanodevices with pH‐sensitive functions has triggered interest in modified oligonucleotides with improved structural properties. We synthesized C‐rich oligonucleotides carrying conformationally restricted (2′S)‐2′‐deoxy‐2′‐C‐methyl‐cytidine units. The effect of this modified nucleoside on the stability of intramolecular i‐motifs from the vertebrate telomere was investigated by UV, CD, and NMR spectroscopy. The replacement of selected positions of the C‐core with C‐modified residues induced the formation of stable intercalated tetraplexes at near‐neutral pH. This study demonstrates the possibility of enhancing the stability of the i‐motif by chemical modification. 相似文献
107.
Early colonization by Zyginidia scutellaris leafhoppers might be a key factor in the attraction and settling of generalist predators, such as Orius spp., in maize fields. In this paper, we aimed to determine whether our observations of early season increases in field populations of Orius spp. reflect a specific attraction to Z. scutellaris-induced maize volatiles, and how the responses of Orius predators to herbivore-induced volatiles (HIPVs) might be affected by previous experiences on plants infested by herbivorous prey. Therefore, we examined the innate and learned preferences of Orius majusculus toward volatiles from maize plants attacked by three potential herbivores with different feeding strategies: the leafhopper Z. scutellaris (mesophyll feeder), the lepidopteran Spodoptera littoralis (chewer), and another leafhopper Dalbulus maidis (phloem feeder). In addition, we examined the volatile profiles emitted by maize plants infested by the three herbivores. Our results show that predators exhibit a strong innate attraction to volatiles from maize plants infested with Z. scutellaris or S. littoralis. Previous predation experience in the presence of HIPVs influences the predator’s odor preferences. The innate preference for plants with cell or tissue damage may be explained by these plants releasing far more volatiles than plants infested by the phloem-sucking D. maidis. However, a predation experience on D. maidis-infested plants increased the preference for D. maidis-induced maize volatiles. After O. majusculus experienced L3-L4 larvae (too large to serve as prey) on S. littoralis-infested plants, they showed reduced attraction toward these plants and an increased attraction toward D. maidis-infested plants. When offered young larvae of S. littoralis, which are more suitable prey, preference toward HIPVs was similar to that of naive individuals. The HIPVs from plants infested by herbivores with distinctly different feeding strategies showed distinguishable quantitative differences in (Z)-3-hexenal, (E)-2-hexenal, and methyl salicylate. These compounds might serve as reliable indicators of prey presence and identity for the predator. Our results support the idea that feeding by Z. scutellaris results in the emission of maize’s HIPVs that initially recruit Orius spp. into maize fields. 相似文献
108.
Pablo Hernndez‐Alonso Nerea Becerra‐Toms Christopher Papandreou Mnica Bull Marta Guasch‐Ferr Estefanía Toledo Miguel Ruiz‐Canela Clary B. Clish Dolores Corella Courtney Dennis Amy Deik Dong D. Wang Cristina Razquin Jean‐Philippe Drouin‐Chartier Ramon Estruch Emilio Ros Montserrat Fit Fernando Ars Miquel Fiol Lluís Serra‐Majem Liming Liang Miguel A Martínez‐Gonzlez Frank B Hu Jordi Salas‐Salvad 《Molecular nutrition & food research》2020,64(12)
109.
110.
Fàbrega C Andreu T Güell F Prades JD Estradé S Rebled JM Peiró F Morante JR 《Nanotechnology》2011,22(23):235403
Highly ordered TiO(2) nanohole layers were synthesized by anodic oxidation of titanium foils using ethylene glycol and ammonium fluoride as the electrolyte. The effectiveness of different methods, namely annealing at 500?°C in NH(3) and in H(2) diluted in N(2), to incorporate nitrogen into TiO(2) and thus extend its photoelectrochemical (PEC) activity to the visible range was studied. The intra-gap levels introduced by both processes were identified by means of XPS and PL measurements. Water splitting experiments demonstrated that annealing in H(2) improved the photocatalytic activity of pure TiO(2), while annealing in ammonia led to a decrease in the PEC performance. 相似文献