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51.
The Rovereto Emotion and Cooperation Corpus (RECC) is a new resource collected to investigate the relationship between cooperation
and emotions in an interactive setting. Previous attempts at collecting corpora to study emotions have shown that this data
are often quite difficult to classify and analyse, and coding schemes to analyse emotions are often found not to be reliable.
We collected a corpus of task-oriented (MapTask-style) dialogues in Italian, in which the segments of emotional interest are
identified using psycho-physiological indexes (Heart Rate and Galvanic Skin Conductance) which are highly reliable. We then
annotated these segments in accordance with novel multimodal annotation schemes for cooperation (in terms of effort) and facial
expressions (an indicator of emotional state). High agreement was obtained among coders on all the features. The RECC corpus
is to our knowledge the first resource with psycho-physiological data aligned with verbal and nonverbal behaviour data. 相似文献
52.
Gelatin reactivity with isocyanate was studied by using the easy detectable 1-naphthyl-isocyanate (NphI). Four different NphI/gelatin
feed ratios were investigated with NphI molar amount ranging between 1/10 and 1/1 with respect to the possible reactive groups
of gelatin. The reactions were carried out at 45 °C in DMSO as solvent, under nitrogen atmosphere. Modified gelatin samples
were characterized by IR, UV–VIS, fluorescence spectroscopies as well as by proton and DOSY NMR. Spectroscopy results allow
to evidence the presence of both bonded and unbonded naphthyl derivatives in the gelatin samples. Unbonded species were present
particularly at the highest NphI/gelatin feed ratio and their formation was correlated to the increasing competition of the
reaction with water since the amount of available reactive groups on gelatin was comparable or smaller than the amount of
residuum water in dry gelatin. 相似文献
53.
54.
Changes in urokinase-plasminogen activator (u-PA) and u-PA receptor (u-PAR) expression at the protein and mRNA level in resting neutrophils and in neutrophils activated by phorbol myristate acetate (PMA) were examined. Low amounts of u-PA were found intracellularly or membrane-bound in resting neutrophils. However, incubation of resting neutrophils with purified exogenous u-PA (10 IU/ml) revealed extensive binding of u-PA to cell membranes. Excess amino-terminal fragment of the u-PA molecule, a proteolytically inactive fragment of u-PA (amino acids 1-135) blocked binding of exogenous u-PA to the cell membrane. These results, collectively, indicate that the binding of u-PA is specific and that resting neutrophils have unoccupied u-PA receptors on their cell membrane. Addition of PMA led to an increase (P < 0.01) in total cell-associated, membrane-bound u-PA activity and u-PA mRNA expression by bovine neutrophils. In contrast. PMA increased u-PAR mRNA levels but this was accompanied by a decrease (2.5-fold; P < 0.01) in free, unoccupied u-PA binding sites. No significant effects on total cell-associated or membrane-bound u-PA were found when neutrophils were treated with 4-phorbol 12,13 didecanoate, a phorbol ester that does not activate protein kinase C (PKC). Furthermore, addition of 1-(5-isoquinolinesylphonyl)-2-methlylpiperazine dihydrochloride (H-7), a potent PKC inhibitor, blocked the effect of PMA on total cell-associated u-PA activity. Thus, PKC plays a role in the modulation of u-PA and u-PAR by PMA in bovine neutrophils. 相似文献
55.
Characterization of microstructured optical fibers for wideband dispersion compensation 总被引:4,自引:0,他引:4
Poli F Cucinotta A Fuochi M Selleri S Vincetti L 《Journal of the Optical Society of America. A, Optics, image science, and vision》2003,20(10):1958-1962
Microstructured optical fibers (MOFs) with small hole-to-hole spacing and large airholes are designed to compensate the anomalous dispersion and the dispersion slope of single-mode fibers. The geometrical parameters that characterize triangular MOFs are chosen to optimize the fiber length and the compensation over a wide wavelength range. A proper design of the photonic crystal fiber geometry allows us to achieve dispersion values of approximately -1700 ps nm(-1) km(-1) at 1550 nm and to compensate the dispersion of standard fibers within +/- 0.5 ps nm(-1) km(-1) over a 100-nm range. The MOF dispersion properties have been studied by means of a numerical simulator for modal analysis based on the finite-element method. 相似文献
56.
James D. Gilardi Sean S. Duffey Charles A. Munn Lisa A. Tell 《Journal of chemical ecology》1999,25(4):897-922
This study tests hypotheses on the biochemical functions of geophagy in parrots: mechanical enhancement of digestion, acid buffering capacity, mineral supplementation, adsorption of dietary toxins, and gastrointestinal cytoprotection. Parrots showed clear preferences for specific soil horizons. Comparisons of preferred and nonpreferred soils from several sites suggest that soils have little ability to enhance grinding and no measurable ability to buffer gastric pH. Soils offered insignificant mineral supplementation since most minerals occurred at similar levels in samples regardless of preference, and the minerals were generally more plentiful in the birds' diets. Sodium was available in moderate levels at some sites (>1000 ppm), but was well below sodium detection thresholds of parrots. X-ray diffraction, cation exchange capacity, and in vitro adsorptive trials showed that the preferred soils are capable of exchanging substantial quantities of cations and are capable of adsorbing low-molecular-weight secondary compounds. In captive Amazona parrots, orally administered clay reduced the bioavailability of the alkaloid quinidine by roughly 60%, demonstrating that in vivo adsorption of potentially toxic compounds may be a biologically important function of geophagy. Labeled clay remained in the lower gastrointestinal tract of captive parrots for >12 hr, which along with high adsorptive capacities, further suggests a potential role in protecting the gastrointestinal lining from various biological and chemical insults. Detoxification and cytoprotection are the most likely functions of geophagy for parrots and herbivores with similar ecologies. Given the variety of chemically defended seeds consumed by these herbivores, geophagy likely protects consumers from dietary toxins, allowing increased diet breadth and/or enhancing digestibility. 相似文献
57.
Federica Zaccheria Rinaldo Psaro Nicoletta Ravasio Laura Sordelli Federica Santoro 《Catalysis Letters》2011,141(4):587-591
Abstract
Styrene oxide can be effectively isomerized to phenyl-acetaldehyde (98%) over amorphous silica alumina catalysts under very mild liquid phase conditions. On the other hand, a copper catalyst prepared using a silica zirconia support gave up to 80% yield in the hydrogenation of styrene oxide to 2-phenyl-ethanol. 相似文献58.
María C. Caracoche Jorge A. Martinez Patricia C. Rivas Fernanda Andreola Federica Bondioli Anna Maria Ferrari Tiziano Manfredini 《Journal of the American Ceramic Society》2008,91(7):2357-2359
This paper deals with the phase stability of an aqueous suspension of tetragonal Zr0.9 Pr0.1 O2 (20 wt%/vol%) at room temperature as a function of the aging time. The suspension is investigated in situ using the highly localized Perturbed Angular Correlations technique. The results indicate that an almost fully reversible degradation process toward monoclinic zirconia takes place through a first-order reaction of rate constant k =0.7 day−1 . Two successive diffusion mechanisms are observed that are interpreted as OH− ions' migration in the grain surface and then, as proton defects' diffusion into the bulk. 相似文献
59.
Ilaria Massarelli Laura Murgia Anna Maria Bianucci Federica Chiellini Emo Chiellini 《International journal of molecular sciences》2007,8(1):13-28
A practical approach for addressing the computer simulation of protein-carbohydrate interactions is described here. An articulated computational protocol was set up and validated by checking its ability to predict experimental data, available in the literature, and concerning the selectivity shown by the Carbohydrate Recognition Domain (CRD) of the human asialoglycoprotein receptor (ASGP-R) toward Gal-type ligands. Some required features responsible for the interactions were identified. Subsequently the same protocol was applied to monomer sugar molecules that constitute the building blocks for alginates and ulvans. Such sugar polymers may supply a low-cost source of rare sugars with a potential impact on several industrial applications, from pharmaceutical to fine chemical industry. An example of their applicative exploitation could be given by their use in developing biomaterial with adhesion properties toward hepatocytes, through interaction with the ASGP-R. Such a receptor has been already proposed as a target for exogenous molecules, specifically in the case of hepatocytes, for diagnostic and therapeutic purposes. The DOCK5.2 program was used to search optimal locations of the above ligands of interest into CRD binding site and to roughly estimate interaction energies. Finally, the binding ΔG of theoretical protein-ligand complexes was estimated by using the DelPhi program in which the solvation free energy is accounted for with a continuum solvent model, by solving the Poisson-Boltzmann equation. The structure analysis of the obtained complexes and their ΔG values suggest that one of the sugar monomers of interest shows the desired characteristics. 相似文献
60.
Synthesis and Antiplasmodial Activity of Novel Chloroquine Analogues with Bulky Basic Side Chains
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Dr. Bruno Tasso Dr. Federica Novelli Dr. Michele Tonelli Dr. Anna Barteselli Dr. Nicoletta Basilico Dr. Silvia Parapini Prof. Donatella Taramelli Prof. Anna Sparatore Prof. Fabio Sparatore 《ChemMedChem》2015,10(9):1570-1583
Chloroquine is commonly used in the treatment and prevention of malaria, but Plasmodium falciparum, the main species responsible for malaria‐related deaths, has developed resistance against this drug. Twenty‐seven novel chloroquine (CQ) analogues characterized by a side chain terminated with a bulky basic head group, i.e., octahydro‐2H‐quinolizine and 1,2,3,4,5,6‐hexahydro‐1,5‐methano‐8H‐pyrido[1,2‐a][1,5]diazocin‐8‐one, were synthesized and tested for activity against D‐10 (CQ‐susceptible) and W‐2 (CQ‐resistant) strains of P. falciparum. Most compounds were found to be active against both strains with nanomolar or sub‐micromolar IC50 values. Eleven compounds were found to be 2.7‐ to 13.4‐fold more potent than CQ against the W‐2 strain; among them, four cytisine derivatives appear to be of particular interest, as they combine high potency with low cytotoxicity against two human cell lines (HMEC‐1 and HepG2) along with easier synthetic accessibility. Replacement of the 4‐NH group with a sulfur bridge maintained antiplasmodial activity at a lower level, but produced an improvement in the resistance factor. These compounds warrant further investigation as potential drugs for use in the fight against malaria. 相似文献