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Dr. Mojtaba Alidoost Anna Mangini Dr. Fabrizio Caldera Dr. Anastasia Anceschi Dr. Julia Amici Dr. Daniele Versaci Dr. Lucia Fagiolari Prof. Francesco Trotta Prof. Carlotta Francia Prof. Federico Bella Prof. Silvia Bodoardo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(6):e202104201
Manufactured globally on industrial scale, cyclodextrins (CD) are cyclic oligosaccharides produced by enzymatic conversion of starch. Their typical structure of truncated cone can host a wide variety of guest molecules to create inclusion complexes; indeed, we daily use CD as unseen components of food, cosmetics, textiles and pharmaceutical excipients. The synthesis of active material composites from CD resources can enable or enlarge the effective utilization of these products in the battery industry with some economical as well as environmental benefits. New and simple strategies are here presented for the synthesis of nanostructured silicon and sulfur composite materials with carbonized hyper cross-linked CD (nanosponges) that show satisfactory performance as high-capacity electrodes. For the sulfur cathode, the mesoporous carbon host limits polysulfide dissolution and shuttle effects and guarantees stable cycling performance. The embedding of silicon nanoparticles into the carbonized nanosponge allows to achieve high capacity and excellent cycling performance. Moreover, due to the high surface area of the silicon composite, the characteristics at the electrode/electrolyte interface dominate the overall electrochemical reversibility, opening a detailed analysis on the behavior of the material in different electrolytes. We show that the use of commercial LP30 electrolyte causes a larger capacity fade, and this is associated with different solid electrolyte interface layer formation and it is also demonstrated that fluoroethylene carbonate addition can significantly increase the capacity retention and the overall performance of our nanostructured Si/C composite in both ether-based and LP30 electrolytes. As a result, an integration of the Si/C and S/C composites is proposed to achieve a complete lithiated Si−S cell. 相似文献
2.
Carlotta?Mummolo Luigi?Mangialardi Joo?H.?KimEmail authorView authors OrcID profile 《Journal of Nonlinear Science》2017,27(4):1291-1323
Instability and risk of fall during standing and walking are common challenges for biped robots. While existing criteria from state-space dynamical systems approach or ground reference points are useful in some applications, complete system models and constraints have not been taken into account for prediction and indication of fall for general legged robots. In this study, a general numerical framework that estimates the balanced and falling states of legged systems is introduced. The overall approach is based on the integration of joint-space and Cartesian-space dynamics of a legged system model. The full-body constrained joint-space dynamics includes the contact forces and moments term due to current foot (or feet) support and another term due to altered contact configuration. According to the refined notions of balanced, falling, and fallen, the system parameters, physical constraints, and initial/final/boundary conditions for balancing are incorporated into constrained nonlinear optimization problems to solve for the velocity extrema (representing the maximum perturbation allowed to maintain balance without changing contacts) in the Cartesian space at each center-of-mass (COM) position within its workspace. The iterative algorithm constructs the stability boundary as a COM state-space partition between balanced and falling states. Inclusion in the resulting six-dimensional manifold is a necessary condition for a state of the given system to be balanced under the given contact configuration, while exclusion is a sufficient condition for falling. The framework is used to analyze the balance stability of example systems with various degrees of complexities. The manifold for a 1-degree-of-freedom (DOF) legged system is consistent with the experimental and simulation results in the existing studies for specific controller designs. The results for a 2-DOF system demonstrate the dependency of the COM state-space partition upon joint-space configuration (elbow-up vs. elbow-down). For both 1- and 2-DOF systems, the results are validated in simulation environments. Finally, the manifold for a biped walking robot is constructed and illustrated against its single-support walking trajectories. The manifold identified by the proposed framework for any given legged system can be evaluated beforehand as a system property and serves as a map for either a specified state or a specific controller’s performance. 相似文献
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Carlotta Borgarelli Yvonne E. Klingl Dr. Abril Escamilla-Ayala Prof. Dr. Sebastian Munck Prof. Dr. Ludo Van Den Bosch Prof. Dr. Wim M. De Borggraeve Dr. Ermal Ismalaj 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(34):8605-8641
Despite the fact that transmembrane proteins represent the main therapeutic targets for decades, complete and in-depth knowledge about their biochemical and pharmacological profiling is not fully available. In this regard, target-tailored small-molecule fluorescent ligands are a viable approach to fill in the missing pieces of the puzzle. Such tools, coupled with the ability of high-precision optical techniques to image with an unprecedented resolution at a single-molecule level, helped unraveling many of the conundrums related to plasma proteins’ life-cycle and druggability. Herein, we review the recent progress made during the last two decades in fluorescent ligand design and potential applications in fluorescence microscopy of voltage-gated ion channels, ligand-gated ion channels and G-coupled protein receptors. 相似文献
5.
Discrete support vector machines (DSVM), originally proposed for binary classification problems, have been shown to outperform
other competing approaches on well-known benchmark datasets. Here we address their extension to multicategory classification,
by developing three different methods. Two of them are based respectively on one-against-all and round-robin classification schemes, in which a number of binary discrimination problems are solved by means of a variant of DSVM. The
third method directly addresses the multicategory classification task, by building a decision tree in which an optimal split
to separate classes is derived at each node by a new extended formulation of DSVM. Computational tests on publicly available
datasets are then conducted to compare the three multicategory classifiers based on DSVM with other methods, indicating that
the proposed techniques achieve significantly higher accuracies.
This research was partially supported by PRIN grant 2004132117. 相似文献
6.
Dr. Dominique Laniel Dr. Florian Trybel Dr. Adrien Néri Yuqing Yin Andrey Aslandukov Dr. Timofey Fedotenko Saiana Khandarkhaeva Dr. Ferenc Tasnádi Dr. Stella Chariton Dr. Carlotta Giacobbe Dr. Eleanor Lawrence Bright Dr. Michael Hanfland Dr. Vitali Prakapenka Prof. Dr. Wolfgang Schnick Prof. Dr. Igor A. Abrikosov Prof. Dr. Leonid Dubrovinsky Prof. Dr. Natalia Dubrovinskaia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(62):e202201998
Non-metal nitrides are an exciting field of chemistry, featuring a significant number of compounds that can possess outstanding material properties. These properties mainly rely on maximizing the number of strong covalent bonds, with crosslinked XN6 octahedra frameworks being particularly attractive. In this study, the phosphorus–nitrogen system was studied up to 137 GPa in laser-heated diamond anvil cells, and three previously unobserved phases were synthesized and characterized by single-crystal X-ray diffraction, Raman spectroscopy measurements and density functional theory calculations. δ-P3N5 and PN2 were found to form at 72 and 134 GPa, respectively, and both feature dense 3D networks of the so far elusive PN6 units. The two compounds are ultra-incompressible, having a bulk modulus of K0=322 GPa for δ-P3N5 and 339 GPa for PN2. Upon decompression below 7 GPa, δ-P3N5 undergoes a transformation into a novel α′-P3N5 solid, stable at ambient conditions, that has a unique structure type based on PN4 tetrahedra. The formation of α′-P3N5 underlines that a phase space otherwise inaccessible can be explored through materials formed under high pressure. 相似文献
7.
Bombelli C Bernardini C Elemento G Mancini G Sorrenti A Villani C 《Journal of the American Chemical Society》2008,130(9):2732-2733
Chiral recognition was observed in a biomembrane model. Micellar aggregates formed by enantiopure N-alkyl-N,N-dimethyl-N-(1-phenyl)ethylammonium bromide were in fact able to convert the racemic mixture of bilirubin-IXalpha into an enantiomerically enriched mixture. The stereochemical preference and the extent of enantiomeric enrichment depend on the length of the hydrophobic portion of the surfactant and on the concentration conditions, and changes in the stereochemical bias are reversible. 相似文献
8.
Fisicaro E Compari C Duce E Contestabili C Viscardi G Quagliotto P 《The journal of physical chemistry. B》2005,109(5):1744-1749
The apparent and partial molar enthalpies, apparent molar volumes, and adiabatic compressibilities at 298 K of the aqueous solutions of the cationic gemini surfactants propanediyl-alpha,omega-bis(octyldimethylammonium bromide) (8-3-8) and propanediyl-alpha,omega-bis(dodecyldimethylammonium bromide) (12-3-12) have been measured as a function of concentration. The trends of the partial molar enthalpies versus concentration are the first well documented thermodynamic evidence of sphere to rod transition in the micellar phase, involving a detectable quantity of heat, and allow the determination of the change in enthalpy associated with this transition. The changes in enthalpies upon micellization and for the sphere to elongated micelles transition, DeltaH(s)(-->)(r), have been obtained from the experimental data by using a pseudo-phase transition approach: -1.5 kJ mol(-1) for 8-3-8 and -3.9 kJ mol(-1) for 12-3-12. No evidence of the above transition is found in the trends of volumetric properties versus m. The apparent adiabatic molar compressibilities for the compounds under investigation are also reported here for the first time: a negative group contribution for the methylene group is evaluated, when the surfactants are present in solution as a single molecule, reflecting its solvation structure. In the micellar phase, the -CH(2)- group contribution becomes positive. A value of 1.17 x 10(-3) cm(3) bar(-1) mol(-1) for the change in adiabatic molar compressibility upon micellization is obtained. The lower values of the methylene group contributions to the volumetric properties for the monomers support the hypothesis of partial association of the chains before the cmc. 相似文献
9.
Study on the variations of the apparent diffusion coefficient in areas of solid tumor in high grade gliomas 总被引:4,自引:0,他引:4
Muti M Aprile I Principi M Italiani M Guiducci A Giulianelli G Ottaviano P 《Magnetic resonance imaging》2002,20(9):635-641
Present knowledge suggests that in glioblastoma multiforme the value of the apparent diffusion coefficient (ADC) is elevated in the solid part and hyperintense in T1, in spite of the elevated cellularity, and also in areas where peritumoral vasogenic edema is present. The purpose of our study has been to verify in vivo if the ADC increases in areas of solid tumor because of an increased presence of edema, like it happens in areas surrounding the tumor. Sixteen patients with histologically verified glioblastoma multiforme underwent a magnetic resonance (MR) examination with sequences: T1-weighted pre and post contrast, diffusion-weighted at b = 0 and b = 1000 s/mm(2), perfusion-weighted. One hundred sixty-five regions of interest (ROI) have been obtained for all set of patients. In each ROI we have estimated 4 parameters: ADC, intensity of T2-signal normalised to the white matter (SI(T2W)(n)), regional cerebral blood volume (rCBV), T1-signal enhancement (E%). With the SI(T2W)(n) the presence of edema was estimated. For each pair of measured parameters a statistical test of linear regression on the set of all ROI was made. A directed linear correlation between: ADC and SI(T2W)(n) (p 相似文献
10.
Fabio RD Alvaro G Bertani B Donati D Giacobbe S Marchioro C Palma C Lynn SM 《The Journal of organic chemistry》2002,67(21):7319-7328
To prepare in multigram scale new antagonists of the glycine binding site associated to the NMDA receptor, an efficient distereoselective route was set up. The addition of suitable allyltin reagents to chiral N-aryl alpha-imino esters (R-(+)-tert-butyl lactate used as chiral auxiliary), gave the corresponding alpha amino acid-type derivative in high chemical yield and optical purity. This allylation reaction represents a novel example of efficient long-range stereodifferentiation process. In the last part of the synthesis, a regioselective Heck-type cyclization reaction enabled preparation of the target tetrasubstituted exocycle and trisubtituted endocycle double bond derivatives. 相似文献