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1.
Young and old adults were asked, in 3 experiments, to make decisions about the identity of line segment patterns after either adding or subtracting line segments from the original pattern. On some of the trials, the line segments from the initial display were presented again in the second display to minimize the necessity of remembering early information during the processing of later information. Although this manipulation presumably reduced the importance of memory in the tasks, it had little effect on the magnitude of the age differences in any of the experiments. Because the 2 groups were equivalent in accuracy of simple recognition judgments, but older adults were less accurate when the same types of decisions were required in the context of an ongoing task, the results suggested that older adults may be impaired in the ability to retain information while simultaneously processing the same or other information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Mobile devices offer a common platform for both leisure and work-related tasks, but this has resulted in a blurred boundary between home and work. In this paper, we explore the security implications of this blurred boundary, both for the worker and the employer. Mobile workers may not always make optimal security-related choices when “on the go” and more impulsive individuals may be particularly affected as they are considered more vulnerable to distraction. In this study, we used a task scenario, in which 104 users were asked to choose a wireless network when responding to work demands while out of the office. Eye-tracking data was obtained from a subsample of 40 of these participants in order to explore the effects of impulsivity on attention. Our results suggest that impulsive people are more frequent users of public devices and networks in their day-to-day interactions and are more likely to access their social networks on a regular basis. However, they are also likely to make risky decisions when working on-the-go, processing fewer features before making those decisions. These results suggest that those with high impulsivity may make more use of the mobile Internet options for both work and private purposes, but they also show attentional behavior patterns that suggest they make less considered security-sensitive decisions. The findings are discussed in terms of designs that might support enhanced deliberation, both in the moment and also in relation to longer term behaviors that would contribute to a better work–life balance.  相似文献   
3.

We design an information retrieval algorithm that mimics the stochastic behavior of decision-makers (DMs) when evaluating the alternatives displayed by an online search engine. The algorithm consists of a decision tree that incorporates all the 1024 decision nodes that may arise from the information retrieval process of DMs. We calibrate the behavior of the algorithm to the one observed from online users and run several sets of 1,000,000 queries. Each query lets DMs decide which subset of the ten alternatives composing the initial page of results to click, allowing us to evaluate their behavior as ranking reliability is assumed to decrease when DMs decide not to click on an alternative. We compare the click-through rates (CTRs) obtained when modifying the degree of ranking reliability derived from the alternatives displayed on the first page of search results. We illustrate how the stability of the CTR prevails among the top-ranked alternatives within relatively reliable scenarios while it drops when imposing large initial decrements in reliability. The resulting consequences regarding the importance of relative ranking positions are analyzed, the top three alternatives exhibiting a generally contained decrease in their CTRs that contrasts with the cumulative pattern arising from the fourth position onwards.

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4.
This paper describes a new application framework (OpenMAF) for rapid development of multimodal applications in computer-aided medicine. MAF applications are multimodal in data, in representation, and in interaction. The framework supports almost any type of biomedical data, including DICOM datasets, motion-capture recordings, or data from computer simulations (e.g. finite element modeling). The interactive visualization approach (multimodal display) helps the user interpret complex datasets, providing multiple representations of the same data. In addition, the framework allows multimodal interaction by supporting the simultaneous use of different input-output devices like 3D trackers, stereoscopic displays, haptics hardware and speech recognition/synthesis systems. The Framework has been designed to run smoothly even on limited power computers, but it can take advantage of all hardware capabilities. The Framework is based on a collection of portable libraries and it can be compiled on any platform that supports OpenGL, including Windows, MacOS X and any flavor of Unix/linux.  相似文献   
5.
Maize germ is a by‐product of the maize milling process that is characterised by a high nutritional value. Currently, heat treatments are employed to prevent full‐fat maize germ from spoilage. The aim of this research was to study the effect of five dry‐heat treatments on the nutritional value of full‐fat maize germ. The results confirmed that after each dry‐heat treatment, the lipase activity decreases but the use of high temperatures could be detrimental for phytosterol and thiamine concentrations. The main negative effects have been observed after treatments at 140 °C for 30 min and 160 °C for 10 min. No significant difference has been observed for protein, ash or fatty acid contents. The treatment at 140 °C for 20 min resulted an optimal combination between temperature and heating time to inactivate lipase without altering deeply the nutritional value and the colour of maize germ.  相似文献   
6.
Synthesis of a polyfluorene/poly(p‐phenylene vinylene) derivative, the Poly [(9,9′‐di‐hexylfluorenediylvinylene‐alt‐1,4‐phenylenevinylene)‐co‐((9,9′‐(3‐t‐butylpropanoate) fluorene‐1,4‐phenylene)] (LaPPS 42) was performed following Wittig and Suzuki routes. Polyfluorenes and derivatives have been used in electroluminescent devices, and the synthesis described here has the advantage in pave the way to get distinct structures having different emission spectra. An extensive study of its electrochemical, thermomechanical, optical, and structural properties was carried out, as well as its application in electroluminescent devices. Polymer light‐emitting diodes (PLEDs) and polymer light‐emitting electrochemical cells (PLECs) were built using LaPPS 42 as active layer, and their electric and optical characterizations confirm they have a potential as active element in electroluminescent devices. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42579.  相似文献   
7.
Polyampholyte latexes can exist within a certain pH range as low‐viscosity aqueous dispersions, while upon a pH shift to the vicinity of the isoelectric point they undergo ionic coacervation. Three classes of coacervation latexes were synthesized and evaluated for their suitability for use in tablet coating applications. Pharmaceutical tablet coatings are commonly based on hydroxypropyl methyl cellulose, poly(vinyl alcohol), and acrylic polymers. Because of the high viscosity of their aqueous solutions, and to the consequent required low concentrations of the tablet coating polymers in the coating solutions to enable sufficiently low viscosity for effective spray application, the current commercial pharmaceutical tablet coating technology requires the removal of large amounts of water during the manufacturing process. In this work, films prepared from high‐solids, low‐viscosity coacervated acrylic latexes showed good hardness, very low tackiness, an excellent combination of optical properties, and very low water vapor permeability. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40049.  相似文献   
8.
Time-resolved grazing-incidence small-angle X-ray scattering (GISAXS) and cryo-microscopy were used for the first time to understand the pore evolution by copolymer assembly, leading to the formation of isoporous membranes with exceptional porosity and regularity. The formation of copolymer micelle strings in solution (in DMF/DOX/THF and DMF/DOX) was confirmed by cryo field emission scanning electron microscopy (cryo-FESEM) with a distance of 72 nm between centers of micelles placed in different strings. SAXS measurement of block copolymer solutions in DMF/DOX indicated hexagonal assembly with micelle-to-micelle distance of 84–87 nm for 14–20 wt% copolymer solutions. GISAXS in-plane peaks were detected, revealing order close to hexagonal. The d-spacing corresponding to the first peak in this case was 100–130 nm (lattice constant 115–150 nm) for 17 wt% copolymer solutions evaporating up to 100 s. Time-resolved cryo-FESEM showed the formation of incipient pores on the film surface after 4 s copolymer solution casting with distances between void centers of 125 nm.  相似文献   
9.
To predict the response of polyethylene thin films subjected to stress for a long time, it is necessary to understand the influence of stress on either the relaxation modulus or creep compliance. Extensive testing has been conducted on 20-micron-thick samples of a particular linear low-density polyethylene film at temperatures from 23°C to −50°C. When reduced to creep compliance and compared with results from dynamic mechanical analysis (DMA), the influence of nonlinearities in the response function is apparent. However, the use of a two-step loading procedure has produced sufficient data to discriminate between the effect of stress on amplitude and time on the creep compliance. It has been found that a master curve of compliance generated by DMA equipment may be used in conjunction with certain nonlinear functions to accurately predict the response of the polyethylene. Perhaps of more importance is the observation that the principles of simple time-temperature superposition, commonly used with linear viscoelastic characterization, are insufficient for use with polyethylene films at most stress levels of interest.  相似文献   
10.
Rice husk, an agricultural waste, is abundantly available in many countries such as China, India, Brazil, US, and South East Asia. Despite the massive production of rice husk, it is mainly disposed to landfill. In this work, utilization of rice husk for a potential waste-water treatment is evaluated, along with subsequent encapsulation of the adsorbed heavy metals (Pb and Cd) inside a porous glass-ceramic. Vitrified bottom ash (another source of waste) was mixed with foaming agents in dif- ferent weight ratios (40:60, 50:50, and 60:40) to prepare a glass matrix for encapsulation of Pb-/Cd-loaded rice husk. It was shown that using 40 wt% vitrified bottom ash with 60 wt% foaming agents leads to a foam glass with the best pore size distribution. Therefore, this batch was further mixed with 70 volume% (5 wt%) heavy metal-loaded rice husk and was heat-treated at 750°C for 3 hours. The final glass-ceramic porous structure was char acterized using SEM, XRD, compression test, and it was shown that it is safe to be used as it passes the EN12457-2 leaching test.  相似文献   
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