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91.
Dr. Michele Panciera Dr. Manuel Amorín Prof. Dr. Juan R. Granja 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10260-10265
The hierarchical self‐assembly properties of a dimer‐forming cyclic peptide that bears a nicotinic acid moiety to form molecular pom‐pom‐like structures are described. This dimeric assembly self organizes into spherical structures that can encapsulate small organic molecules owing to its porosity and it can also facilitate metal deposition on its surface directed by the pyridine moiety. 相似文献
92.
Michele Cacioppo Tobias Scharl Dr. Luka Đorđević Dr. Alejandro Cadranel Dr. Francesca Arcudi Prof. Dirk M. Guldi Prof. Maurizio Prato 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12879-12884
Carbon dots (CDs) and their derivatives are useful platforms for studying electron-donor/acceptor interactions and dynamics therein. Herein, we couple amorphous CDs with phthalocyanines (Pcs) that act as electron donors with a large extended π-surface and intense absorption across the visible range of the solar spectrum. Investigations of the intercomponent interactions by means of steady-state and pump-probe transient absorption spectroscopy reveal symmetry-breaking charge transfer/separation and recombination dynamics within pairs of phthalocyanines. The CDs facilitate the electronic interactions between the phthalocyanines. Thus, our findings suggest that CDs could be used to support electronic couplings in multichromophoric systems and further increase their applicability in organic electronics, photonics, and artificial photosynthesis. 相似文献
93.
94.
Michele Lo Giudice Giuseppe Varone Cosimo Ieracitano Nadia Mammone Giovanbattista Gaspare Tripodi Edoardo Ferlazzo Sara Gasparini Umberto Aguglia Francesco Carlo Morabito 《Entropy (Basel, Switzerland)》2022,24(1)
The differential diagnosis of epileptic seizures (ES) and psychogenic non-epileptic seizures (PNES) may be difficult, due to the lack of distinctive clinical features. The interictal electroencephalographic (EEG) signal may also be normal in patients with ES. Innovative diagnostic tools that exploit non-linear EEG analysis and deep learning (DL) could provide important support to physicians for clinical diagnosis. In this work, 18 patients with new-onset ES (12 males, 6 females) and 18 patients with video-recorded PNES (2 males, 16 females) with normal interictal EEG at visual inspection were enrolled. None of them was taking psychotropic drugs. A convolutional neural network (CNN) scheme using DL classification was designed to classify the two categories of subjects (ES vs. PNES). The proposed architecture performs an EEG time-frequency transformation and a classification step with a CNN. The CNN was able to classify the EEG recordings of subjects with ES vs. subjects with PNES with 94.4% accuracy. CNN provided high performance in the assigned binary classification when compared to standard learning algorithms (multi-layer perceptron, support vector machine, linear discriminant analysis and quadratic discriminant analysis). In order to interpret how the CNN achieved this performance, information theoretical analysis was carried out. Specifically, the permutation entropy (PE) of the feature maps was evaluated and compared in the two classes. The achieved results, although preliminary, encourage the use of these innovative techniques to support neurologists in early diagnoses. 相似文献
95.
Gian Tommaso Viola Michele Bortolotti Alessandro Zazzetta 《Journal of polymer science. Part A, Polymer chemistry》1996,34(1):13-24
UV absorption spectra of thermolyzed polybutadienyl- and polyisoprenyl-lithium reveal a chromophore group previously not recognized for such systems; its absorption band at 271 nm has been assigned to a structure with three conjugated double bonds. A two-step mechanism for the formation of this trienic structure is proposed: an intermolecular metallation of associated living ends is followed by lithium hydride (LiH) elimination. Along thermolysis the presence of a dienic structure was also recognized, the latter arising from intramolecular elimination of LiH. The trienyllithium structure is also considered to be an effective species for the observed molecular weight distribution (MWD) variations. The observed different extent of high molecular weight (HMW) for polyisoprenyl- and polybutadienyl-lithium is explained on the basis of a different stability of the intermediates present along the proposed reaction mechanism. The thermolytic behavior of polystyryllithium does not provide any significant change in MWD: the disappearance of the living chain ends, UV detected, is due to an intramolecular LiH elimination which obeys first-order kinetics. The influence of temperature and of the tetrahydrofuran (THF) level on kinetic rate constants was investigated. © 1996 John Wiley & Sons, Inc. 相似文献
96.
Iacus Stefano Maria Santamaria Carlos Sermi Francesco Spyratos Spyros Tarchi Dario Vespe Michele 《Nonlinear dynamics》2020,101(3):1901-1919
Nonlinear Dynamics - Countries in Europe took different mobility containment measures to curb the spread of COVID-19. The European Commission asked mobile network operators to share on a... 相似文献
97.
Jiacheng Lin Chiara Figazzolo Michael A. Metrick II Pietro Sormanni Michele Vendruscolo 《Chemical science》2021,12(41):13940
The expansion of structural databases and the increase in computing power are enabling approaches for antibody discovery based on computational design. It has already been shown that it is possible to use this approach to generate antibodies for specific epitopes on challenging targets. Here we describe an application of this procedure for antibody maturation through the computational design of mutational variants of increased potency. We illustrate this procedure in the case of a single-domain antibody targeting an epitope in the N-terminal region of Aβ42, a peptide whose aggregation is closely associated with Alzheimer''s disease. We show that this approach enables the generation of an antibody variant with over 200-fold increased potency against the primary nucleation process in Aβ42 aggregation. Our results thus demonstrate that potentiated antibody variants can be obtained by computational maturation.A computational maturation method enables the generation of an antibody variant with over 200-fold increased potency against the primary nucleation process in Aβ42 aggregation. 相似文献
98.
Michele Arcangelo Quinto Juan Manuel Monti Mario Enrique Alcocer Avila Philippe F. Weck Omar Ariel Fojón Roberto Daniel Rivarola Christophe Champion 《X射线光谱测定》2020,49(1):95-98
The present work focuses on studying the contribution of the Auger electron emission in proton-induced interactions in biological matter. The Monte Carlo track-structure code, TILDA-V, was then used for modeling the protons beams of 10 keV to 100 MeV in biological matter, namely, water vapor and hydrated DNA. The main ionizing processes are described by means of an extensive set of ab initio differential and total cross sections computed within a quantum-mechanical CDW-EIS approximation. 相似文献
99.
Emission of volatile sesquiterpenes and monoterpenes in grapevine genotypes following Plasmopara viticola inoculation in vitro
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Alberto Algarra Alarcon Valentina Lazazzara Luca Cappellin Pier Luigi Bianchedi Rainer Schuhmacher Georg Wohlfahrt Ilaria Pertot Franco Biasioli Michele Perazzolli 《Journal of mass spectrometry : JMS》2015,50(8):1013-1022
The grapevine (Vitis vinifera) is one of the most widely cultivated fruit crops globally, and one of its most important diseases in terms of economic losses is downy mildew, caused by Plasmopara viticola. Several wild Vitis species have been found to be resistant to this pathogen and have been used in breeding programs to introduce resistance traits to susceptible cultivars. Plant defense is based on different mechanisms, and volatile organic compounds (VOCs) play a major role in the response to insects and pathogens. Although grapevine resistance mechanisms and the production of secondary metabolites have been widely characterized in resistant genotypes, the emission of VOCs has not yet been investigated following P. viticola inoculation. A Proton Transfer Reaction‐Time of Flight‐Mass Spectrometer (PTR‐ToF‐MS) was used to analyze the VOCs emitted by in vitro‐grown plants of grapevine genotypes with different levels of resistance. Downy mildew inoculation significantly increased the emission of monoterpenes and sesquiterpenes by the resistant SO4 and Kober 5BB genotypes, but not by the susceptible V. vinifera Pinot noir. Volatile terpenes were implicated in plant defense responses against pathogens, suggesting that they could play a major role in the resistance against downy mildew by direct toxicity or by inducing grapevine resistance. The grapevine genotypes differed in terms of the VOC emission pattern of both inoculated and uninoculated plants, indicating that PTR‐ToF‐MS could be used to screen hybrids with different levels of downy mildew resistance. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
100.
Analysis of polycyclic aromatic hydrocarbons (PAHs) in environmental samples: a critical review of gas chromatographic (GC) methods 总被引:1,自引:0,他引:1
Polycyclic aromatic hydrocarbons (PAHs) are frequently measured in the atmosphere for air quality assessment, in biological
tissues for health-effects monitoring, in sediments and mollusks for environmental monitoring, and in foodstuffs for safety
reasons. In contemporary analysis of these complex matrices, gas chromatography (GC), rather than liquid chromatography (LC),
is often the preferred approach for separation, identification, and quantification of PAHs, largely because GC generally affords
greater selectivity, resolution, and sensitivity than LC. This article reviews modern-day GC and state-of-the-art GC techniques
used for the determination of PAHs in environmental samples. Standard test methods are discussed. GC separations of PAHs on
a variety of capillary columns are examined, and the properties and uses of selected mass spectrometric (MS) techniques are
presented. PAH literature on GC with MS techniques, including chemical ionization, ion-trap MS, time-of-flight MS (TOF-MS),
and isotope-ratio mass spectrometry (IRMS), is reviewed. Enhancements to GC, for example large-volume injection, thermal desorption,
fast GC, and coupling of GC to LC, are also discussed with regard to the determination of PAHs in an effort to demonstrate
the vigor and robustness GC continues to achieve in the analytical sciences. 相似文献