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91.
The goal of the study was to examine whether speakers naming pairs of objects would retrieve the names of the objects in parallel or in sequence. To this end, we recorded the speakers’ eye movements and determined whether the difficulty of retrieving the name of the 2nd object affected the duration of the gazes to the 1st object. Two experiments, which differed in the spatial arrangement of the objects, showed that the speakers looked longer at the 1st object when the name of the 2nd object was easy than when it was more difficult to retrieve. Thus, the easy 2nd-object names interfered more with the processing of the 1st object than the more difficult 2nd-object names. In the 3rd experiment, the processing of the 1st object was rendered more difficult by presenting it upside down. No effect of 2nd-object difficulty on the gaze duration for the 1st object was found. These results suggest that speakers can retrieve the names of a foveated and an extrafoveal object in parallel, provided that the processing of the foveated object is not too demanding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
Previous studies reported on the broad-spectrum antiviral function of heparin. Here we investigated the antiviral function of magnesium-modified heparin and found that modified heparin displayed a significantly enhanced antiviral function against human adenovirus (HAdV) in immortalized and primary cells. Nuclear magnetic resonance analyses revealed a conformational change of heparin when complexed with magnesium. To broadly explore this discovery, we tested the antiviral function of modified heparin against herpes simplex virus type 1 (HSV-1) and found that the replication of HSV-1 was even further decreased compared to aciclovir. Moreover, we investigated the antiviral effect against the new severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and measured a 55-fold decreased viral load in the supernatant of infected cells associated with a 38-fold decrease in virus growth. The advantage of our modified heparin is an increased antiviral effect compared to regular heparin.  相似文献   
93.
Multiple stable isotope ratios (δ2H, δ13C, δ18O and δ34S) were measured in muscle, muscle lipids and lipid fractions collected from 28 lambs, subjected to a diet-switch and raised on two energy allowances (EAs), to determine tissue turnover and diet-tissue fractionation. The diet-muscle fractionations prior to the diet-switch were estimated to be −44.0‰, +1.9‰ and 0‰ for H, C and S, respectively, while the drinking water was demonstrated to be the main source of muscle O and thus δ18O variation. The diet-intra-muscular lipid fractionations prior to the diet-switch were estimated to be −172.7‰, −1.3‰ and −11.5‰ for H, C and O, respectively. The C half-lives of muscle were determined to be 75.7 and 91.6 days for animals receiving the high and low EA, respectively. Extracting temporally resolved pre-slaughter dietary information from meat by analysing bulk muscle, muscle lipids and muscle lipid fractions appeared to be not practicable due to possible incomplete turnover of lipids.  相似文献   
94.
P. A. Starreveld and W. La Heij (see record 1995-42762-001) tested the seriality view of lexical access in speech production, according to which lexical selection and the encoding of a word's form proceed in serial order without feedback. In 2 experiments, they looked at the combined effect of semantic and orthographic relatedness of written distractor words in tasks that required conceptually driven naming. They found an interaction between semantic relatedness and orthographic relatedness and argued that the observed interaction refutes the seriality view of lexical access. In this comment, the authors argue that Starreveld and La Heij's rejection of serial access was based on an oversimplified conception of the seriality view and that interaction, rather than additivity, is predicted by existing conceptions of serial access. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
Electron microscopic investigations of magnetron sputtered amorphous SiNx-coatings showed, that morphology changes with variation of working gas pressure and substrate position corresponding to the Structure Zone Model by Thornton. Increasing working gas pressure and displacement of substrate to larger radial distances influence columnar structures. Energy of particles and adatom mobility decrease with increasing pressure. In positions far from the centre of deposition there are more particles with oblique incidence. This leads to a shadowing mechanism. Columnar diameter increases and packing density decreases. The influence of working gas pressure and angle of incidence bears also an effect on the behaviour of mechanical stress. Coatings with coarse columnar structures have lower mechanical stress than coatings with fine columnar structures.  相似文献   
96.
The emergence of antibiotic‐resistant bacteria and the failure of the existing antibacterial therapeutics call for development of novel treatment strategies. Furthermore, the formation of bacterial biofilms restricts drug penetration and efficiency, causing life‐threatening infections. Bacterial attachment and biofilm formation are regulated by the cell‐to‐cell communication phenomenon called quorum sensing (QS). In this work, antimicrobial silver nanoparticles (AgNPs) are decorated in a layer‐by‐layer fashion with the oppositely charged aminocellulose (AM) and acylase to generate hybrid nanoentities with enhanced antibacterial and antibiofilm activities as well as reduced cytotoxicity. Acylase, a quorum‐quenching enzyme that degrades the QS signals in the extracellular environment of bacteria, disrupts the bacterial QS process and together with the bactericidal AM synergistically lowers fourfold the minimum inhibitory concentration of the AgNPs templates toward Gram‐negative Pseudomonas aeruginosa (P. aeruginosa). The hybrid nanoparticles in eightfold‐lower concentration than the AgNPs inhibit 45% of the QS‐regulated virulence factors produced by the reporter Chromobacterium violaceum bacterial strain and reduce by 100% the P. aeruginosa biofilm formation. Moreover, the sequential deposition of antibacterial/antibiofilm active and biocompatible biopolymers onto the AgNPs allows the engineering of safe nanomaterials that do not affect the viability of human cells.  相似文献   
97.
Three dual-task experiments investigated the capacity demands of phoneme selection in picture naming. On each trial, participants named a target picture (Task 1) and carried out a tone discrimination task (Task 2). To vary the time required for phoneme selection, the authors combined the targets with phonologically related or unrelated distractor pictures (Experiment 1) or words, which were clearly visible (Experiment 2) or masked (Experiment 3). When pictures or masked words were presented, the tone discrimination and picture naming latencies were shorter in the related condition than in the unrelated condition, which indicates that phoneme selection requires central processing capacity. However, when the distractor words were clearly visible, the facilitatory effect was confined to the picture naming latencies. This pattern arose because the visible related distractor words facilitated phoneme selection but slowed down speech monitoring processes that had to be completed before the response to the tone could be selected. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
Although an isolated individual molecule clearly has only one ionization potential, multiple values are found for molecules in ordered assemblies. Photoelectron spectroscopy of archetypical pi-conjugated organic compounds on metal substrates combined with first-principles calculations and electrostatic modelling reveal the existence of a surface dipole built into molecular layers. Conceptually different from the surface dipole at metal surfaces, its origin lies in details of the molecular electronic structure and its magnitude depends on the orientation of molecules relative to the surface of an ordered assembly. Suitable pre-patterning of substrates to induce specific molecular orientations in subsequently grown films thus permits adjusting the ionization potential of one molecular species over up to 0.6 eV via control over monolayer morphology. In addition to providing in-depth understanding of this phenomenon, our study offers design guidelines for improved organic-organic heterojunctions, hole- or electron-blocking layers and reduced barriers for charge-carrier injection in organic electronic devices.  相似文献   
99.
We present a workflow for kinetic modeling of biocatalytic reactions which combines methods from Bayesian learning and uncertainty quantification for model calibration, model selection, evaluation, and model reduction in a consistent statistical framework. Our workflow is particularly tailored to sparse data settings in which a considerable variability of the parameters remains after the models have been adapted to available data, a ubiquitous problem in many real-world applications. Our workflow is exemplified on an enzyme-catalyzed two-substrate reaction mechanism describing the symmetric carboligation of 3,5-dimethoxy-benzaldehyde to (R)-3,3′,5,5′-tetramethoxybenzoin catalyzed by benzaldehyde lyase from Pseudomonas fluorescens. Results indicate a substrate-dependent inactivation of enzyme, which is in accordance with other recent studies.  相似文献   
100.
Wearable electrochemical biosensors for sweat analysis present a promising means for noninvasive biomarker monitoring. However, sweat‐based sensing still poses several challenges, including easy degradation of enzymes and biomaterials with repeated testing, limited detection range and sensitivity of enzyme‐based biosensors caused by oxygen deficiency in sweat, and poor shelf life of sensors using all‐in‐one working electrodes patterned by traditional techniques (e.g., electrodeposition and screen printing). Herein, a stretchable, wearable, and modular multifunctional biosensor is developed, incorporating a novel MXene/Prussian blue (Ti3C2Tx/PB) composite designed for durable and sensitive detection of biomarkers (e.g., glucose and lactate) in sweat. A unique modular design enables a simple exchange of the specific sensing electrode to target the desired analytes. Furthermore, an implemented solid–liquid–air three‐phase interface design leads to superior sensor performance and stability. Typical electrochemical sensitivities of 35.3 µA mm ?1 cm?2 for glucose and 11.4 µA mm ?1 cm?2 for lactate are achieved using artificial sweat. During in vitro perspiration monitoring of human subjects, the physiochemistry signals (glucose and lactate level) can be measured simultaneously with high sensitivity and good repeatability. This approach represents an important step toward the realization of ultrasensitive enzymatic wearable biosensors for personalized health monitoring.  相似文献   
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