361 research outputs found
Effet du port du corset de Boston sur l'équilibre des jeunes filles ayant une scoliose idiopathique de l'adolescence
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal
Duelo de titanes: tensiones entre India y China
La novena cumbre de los BRICS, llevada a cabo enXiamen, China, al inicio de septiembre de 2017, fue el escenario del primer encuentro bilateral sustantivo entre representantes de China e India (ambos potencias nucleares), tras el incidente de Doklam. En ese marco, el Secretario de Asuntos Exteriores indio, S. Jaishankar, señaló que el encuentro entre el Primer Ministro Modi y el Premier chino, Xi Jinping, reafirmó la idea de que tener buenas relaciones forma parte del mutuo interés, siendo necesario contar con una mayor comunicación entre el personal de defensa y seguridad de ambos países. Tal comunicación durante la misma cumbre, fue parte de un conjunto de señales y expresiones por parte de ambos gobiernos, en dirección a bajar el tono de la tensión entre ambos, precedida por el acuerdo acerca de una "pronta desconexión" de las fuerzas militares de ambos países en la zona en disputa en el Himalaya, hacia fines de agosto (Miglani y Blanchard, 2017)
Polyphenolic C-glucosidic ellagitannins present in oak-aged wine inhibit HIV-1 nucleocapsid protein
HIV-1 nucleocapsid protein (NC) is a nucleic acid chaperone implicated in several steps of the virus replication cycle and an attractive new target for drug development. In reverse transcription, NC destabilizes nucleic acid secondary structures and catalyzes the annealing of HIV-1 TAR RNA to its DNA copy (cTAR) to form the heteroduplex TAR/cTAR. A screening program led to the identification of the plant polyphenols acutissimins A and B as potent inhibitors of NC in different assays. These two flavano-ellagitannins, which are found in wine aged in oak barrels, exhibited different mechanisms of protein inhibition and higher potency relatively to their epimers, epiacutissimins A and B, and to simpler structures notably representing hydrolytic fragments and metabolites therefrom
A complex relationship between immunity and metabolism in Drosophila diet-induced insulin resistance
Hydrides as high capacity anodes in lithium cells: an Italian “Futuro in Ricerca di Base FIRB-2010” project
Automotive and stationary energy storage are among the most recently-proposed and still
unfulfilled applications for lithium ion devices. Higher energy, power and superior safety standards,
well beyond the present state of the art, are actually required to extend the Li-ion battery market to
these challenging fields, but such a goal can only be achieved by the development of new materials
with improved performances. Focusing on the negative electrode materials, alloying and conversion
chemistries have been widely explored in the last decade to circumvent the main weakness of the
intercalation processes: the limitation in capacity to one or at most two lithium atoms per host
formula unit. Among all of the many proposed conversion chemistries, hydrides have been proposed
and investigated since 2008. In lithium cells, these materials undergo a conversion reaction that
gives metallic nanoparticles surrounded by an amorphous matrix of LiH. Among all of the reported
conversion materials, hydrides have outstanding theoretical properties and have been only marginally
explored, thus making this class of materials an interesting playground for both fundamental and
applied research. In this review, we illustrate the most relevant results achieved in the frame of the
Italian National Research Project FIRB 2010 Futuro in Ricerca “Hydrides as high capacity anodes in
lithium cells” and possible future perspectives of research for this class of materials in electrochemical
energy storage devices
Integrated 3D information for custom-made bone grafts: focus on biphasic calcium phosphate bone substitute biomaterials
none5Purpose: Several studies showed that the sintering temperature of 1250 °C could affect the formation of α-Ca3(PO4)2, which is responsible for the reduction of the hardness value of biphasic calcium phosphate biocomposites, but they did not evaluate the inference of the sintering time at peak temperature on transition of β-Ca3(PO4)2 to α-Ca3(PO4)2. This analysis explored, in an innovative way, inferences and correlations between volumetric microstructure, mechanical properties, sintering temperature, and time at peak temperature in order to find the best sintering conditions for biphasic calcium phosphate composites grafted in severe alveolar bone defects. Methods: Sintered biphasic calcium phosphates (30%-hydroxyapatite/70%-tricalcium phosphate) were tested by microCT imaging for the 3D morphometric analysis, by compressive loading to find their mechanical parameters, and by X-ray diffraction to quantify the phases via Rietveld refinement for different sintering temperatures and times at the peak temperature. Data were analysed in terms of statistical inference using Pearson’s correlation coefficients. Results: All the studied scaffolds closely mimicked the alveolar organization of the jawbone, independently on the sintering temperatures and times; however, mechanical testing revealed that the group with peak temperature, which lasted for 2 hours at 1250 °C, showed the highest strength both at the ultimate point and at fracture point. Conclusion: The good mechanical performances of the group with peak temperature, which lasted for 2 hours at 1250 °C, is most likely due to the absence of the α-Ca3(PO4)2 phase, as revealed by X-ray diffraction. However, we detected its presence after sintering at the same peak temperature for longer times, showing the time-dependence, combined with the temperature-dependence, of the β-Ca3(PO4)2 to α-Ca3(PO4)2 transition.openAlessandra Giuliani; Maria Laura Gatto; Luigi Gobbi; Francesco Guido Mangano; Carlo ManganoGiuliani, Alessandra; Gatto, MARIA LAURA; Gobbi, Luigi; Guido Mangano, Francesco; Mangano, Carl
Mechanisms of HIV-1 Nucleocapsid Protein Inhibition by Lysyl-Peptidyl-Anthraquinone Conjugates
The Nucleocapsid protein NCp7 (NC) is a nucleic acid chaperone responsible for essential steps of the HIV-1 life cycle and an attractive candidate for drug development. NC destabilizes nucleic acid structures and promotes the formation of annealed substrates for HIV-1 reverse transcription elongation. Short helical nucleic acid segments bordered by bulges and loops, such as the Trans-Activation Response element (TAR) of HIV-1 and its complementary sequence (cTAR), are nucleation elements for helix destabilization by NC and also preferred recognition sites for threading intercalators. Inspired by these observations, we have recently demonstrated that 2,6-disubstituted peptidylanthraquinone-conjugates inhibit the chaperone activities of recombinant NC in vitro, and that inhibition correlates with the stabilization of TAR and cTAR stem-loop structures. We describe here enhanced NC inhibitory activity by novel conjugates that exhibit longer peptidyl chains ending with a conserved Nterminal lysine. Their efficient inhibition of TAR/cTAR annealing mediated by NC originates from the combination of at least three different mechanisms, namely, their stabilizing effects on nucleic acids dynamics by threading intercalation, their ability to target TAR RNA substrate leading to a direct competition with the protein for the same binding sites on TAR, and, finally, their effective binding to the NC protein. Our results suggest that these molecules may represent the stepping-stone for the future development of NC-inhibitors capable of targeting the protein itself and its recognition site in RNA
Socio-economic and institutional effects of windstorms damaging forests: preliminary observations from European cases and Vaia windstorm
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