912 resultados para Technology and state
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A wide-ranging multiprofessional research project explored issues relating to the introduction of assistive technology into the existing homes of older people in order to provide them with the opportunity to remain at home. The financial relationship between assistive technology and packages of formal care was also explored. The costs of residential care and those of a number of packages containing differing quantities of assistive technology, formal care and informal care were compared. The analyses provide a strong financial case for substituting and/or supplementing formal care with assistive technology, even for individuals with quite disabling conditions. Although needs and hence the cost of provision rise with an increasing level of disability, the savings in care costs accrue quickly. The consideration of a variety of users with different needs and informal care provision, and occupying a very wide range of housing, leads to the conclusion that in comparison with traditional care packages, at worst, incorporating significant amounts of assistive technology into care packages is cost neutral, but that with careful specification of assistive technology major savings are feasible.
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A novel optimising controller is designed that leads a slow process from a sub-optimal operational condition to the steady-state optimum in a continuous way based on dynamic information. Using standard results from optimisation theory and discrete optimal control, the solution of a steady-state optimisation problem is achieved by solving a receding-horizon optimal control problem which uses derivative and state information from the plant via a shadow model and a state-space identifier. The paper analyzes the steady-state optimality of the procedure, develops algorithms with and without control rate constraints and applies the procedure to a high fidelity simulation study of a distillation column optimisation.
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As healthcare costs rise and an aging population makes an increased demand on services, so new techniques must be introduced to promote an individuals independence and provide these services. Robots can now be designed so they can alter their dynamic properties changing from stiff to flaccid, or from giving no resistance to movement, to damping any large and sudden movements. This has some strong implications in health care in particular for rehabilitation where a robot must work in conjunction with an individual, and might guiding or assist a persons arm movements, or might be commanded to perform some set of autonomous actions. This paper presents the state-of-the-art of rehabilitation robots with examples from prosthetics, aids for daily living and physiotherapy. In all these situations there is the potential for the interaction to be non-passive with a resulting potential for the human/machine/environment combination to become unstable. To understand this instability we must develop better models of the human motor system and fit these models with realistic parameters. This paper concludes with a discussion of this problem and overviews some human models that can be used to facilitate the design of the human/machine interfaces.
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Firm size is found to affect strategic decisions significantly, whereas technology and market stability stimulate product development and innovation.
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Recent research into sea ice friction has focussed on ways to provide a model which maintains much of the clarity and simplicity of Amonton's law, yet also accounts for memory effects. One promising avenue of research has been to adapt the rate- and state- dependent models which are prevalent in rock friction. In such models it is assumed that there is some fixed critical slip displacement, which is effectively a measure of the displacement over which memory effects might be considered important. Here we show experimentally that a fixed critical slip displacement is not a valid assumption in ice friction, whereas a constant critical slip time appears to hold across a range of parameters and scales. As a simple rule of thumb, memory effects persist to a significant level for 10 s. We then discuss the implications of this finding for modelling sea ice friction and for our understanding of friction in general.
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We report on use of iPads (and other IOS devices) for student fieldwork use and as electronic field notebooks and to promote active. We have used questionnaires and interviews of tutors and students to elicit their views and technology and iPad use for fieldwork. There is some reluctance for academic staff to relinquish paper notebooks for iPad use, whether in the classroom or on fieldwork, as well as use them for observational and measurement purposes. Students too are largely unaware of the potential of iPads for enhancing fieldwork. Apps can be configured for a wide variety of specific uses that make iPads useful for educational as well as social uses. Such abilities should be used to enhance existing practice as well as make new functionality. For example, for disabled students who find it difficult to use conventional note taking. iPads can be used to develop student self-directed learning and for group contributions. The technology becomes part of the students’ personal learning environments as well as at the heart of their knowledge spaces – academic and social. This blurring of boundaries is due to iPads’ usability to cultivate field use, instruction, assessment and feedback processes. iPads can become field microscopes and entries to citizen science and we see the iPad as the main ‘computing’ device for students in the near future. As part of the Bring Your Own Technology/Device (BYOD) the iPad has much to offer although, both staff and students need to be guided in the most effective use for self-directed education via development of Personal Learning Environments. A more student-oriented pedagogy is suggested to correspond to the increasing use of tablet technologies by students
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Considerable efforts have been expended in elucidating the inter-cellular and intra-cellular signaling pathways which elicit cardiac myocyte hypertrophy or apoptosis, and in identifying the changes which are associated with the end-stage of the response. The challenge now is to link the two. Although some of the signaling effects will be the acute modulation of existing protein function, long-term effects which bring about and maintain the hypertrophic state or which culminate in cell death are mediated at the level of gene and protein expression. With the advances in micro-array technology and genome sequencing, it is now possible to obtain a picture of the global gene expression profile in myocytes or in whole heart which dictates the proteins which could be made. This is not the final picture since additional regulation at the level of translation modulates the relative proportions of each protein that can be made from the transcriptome. Even here, further regulation of protein stability and turnover means that ultimately it is still necessary to examine the proteome to determine what may cause the functional changes in a cell. Thus, in order to gain a full picture of events which regulate the response and gain some insight into possible points of intervention for therapy, it is necessary to examine gene expression, mRNA translation and protein expression in concert.
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Zinc protoporphyrin IX (ZnPP), the major red pigment in hams dry-cured without nitrates/nitrites, is an efficient photosensitizer, which upon absorption of visible light forms short-lived excited singlet state ((1)ZnPP*) and by intersystem crossing yields the very reactive triplet-excited state ((3)ZnPP*). Using nano-second laser flash photolysis and transient absorption spectroscopy NADH, ascorbic acid, hemin and dehydroascorbic acid were each found to be efficient quenchers of (3)ZnPP*. The deactivation followed, in homogeneous dimethyl sulfoxide (DMSO) or DMSO:water (1:1) solutions, second-order kinetics. The rate constant for ascorbic acid and NADH for reductive quenching of (3)ZnPP* was at 25 A degrees C found to be 7.5 +/- A 0.1 x 10(4) L mol(-1) s(-1) and 6.3 +/- A 0.1 x 10(5) L mol(-1) s(-1), respectively. The polyphenols catechin and quercetin had no effect on (3)ZnPP*. The quenching rate constant for oxidative deactivation of (3)ZnPP* by dehydroascorbic acid and hemin was at 25 A degrees C: 1.6 +/- A 0.1 x 10(5) L mol(-1) s(-1) and 1.47 +/- A 0.1 x 10(9) L mol(-1) s(-1), respectively. Oxidized glutathione did not act as an oxidative quencher for (3)ZnPP*. After photoexcitation of ZnPP to (1)ZnPP*, fluorescence was only found to be quenched by the presence of hemin in a diffusion-controlled reaction. The efficient deactivation of (3)ZnPP* and (1)ZnPP* by the metalloporphyrin (hemin) naturally present in meat may accordingly inherently protect meat proteins and lipids against ZnPP photosensitized oxidation.
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This article investigates the causes in the reduction of labor force participation of the old. We argue that the changes in social security policy, in technology and in demography may account for most of the changes in retirement over the second part of the last century in the U.S. economy. We develop a dynamic general equilibrium model with endogenous retirement that embeds social security legislation. The model is able to match very closely the increase in the retirement rate of males aged 65 and older. It also quanti es the isolated impact on retirement and on the solvency of the social security system of the di¤erent factors. The model suggests that technological and demographic changes had a strong in uence on retirement, so that it would have increased signi cantly even if the social security rules had not changed. However, as the latter became much more generous in the past, changes in social security policy can account not only for a sizeable part of the expansion of retirement, but also for the most of the observed increase in the social security expenses as a share of GDP.
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This article investigates the causes in the reduction of labor force participation of the old. We argue that the changes in social security policy, in technology and in demography may account for most of the changes in retirement over the second part of the last century in the U.S. economy. We develop a dynamic general equilibrium model with endogenous retirement that embeds social security legislation. The model is able to match very closely the increase in the retirement rate of males aged 65 and older. It also quanti es the isolated impact on retirement and on the solvency of the social security system of the di¤erent factors. The model suggests that technological and demographic changes had a strong in uence on retirement, so that it would have increased signi cantly even if the social security rules had not changed. However, as the latter became much more generous in the past, changes in social security policy can account not only for a sizeable part of the expansion of retirement, but also for the most of the observed increase in the social security expenses as a share of GDP.
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This paper argues that monetary models can and usually present the phenomenon of over-banking; that is, the market solution of the model presents a size of the banking sector which is higher than the social optima. Applying a two sector monetary model of capital accumulation in presence of a banking sector, which supplies liquidity services, it is shown that the rise of a tax that disincentives the acquisition of the banking service presents the following impacts on welfare. If the technology is the same among the sectors, the tax increases welfare; otherwise, steady-state utility increase if the banking sector is labor-intensive compared to the real sector. Additionally, it is proved that the elevation of inflation has the following impact on the economy's equilibrium: the share on the product of the banking sector increases; the product and the stock of capital increases or reduces whether the banking sector is capital-intensive or laborintensive; and, the steady-state utility reduces. The results were derived under a quite general set up - standard hypothesis regarding concavity of preference, convexity of technology, and normality of goods - were required.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The aim of this study was to investigate the students' preferred teaching techniques, such as traditional blackboard, power-point, or slide-projection, for biochemistry discipline in biomedicine and medicine courses from São Paulo State University, UNESP, Botucatu, São Paulo, Brazil. Preferences for specific topic and teaching techniques were determined from questionnaires on a Liquert scale from 1 to 5 (strongly disagree; disagree; neither agree, nor disagree; agree; strongly agree) distributed at the end of biochemistry discipline to 180 biomedical students (30 students/year) and 540 medical students (90 students/year), during the years 2000-2005. Despite of the different number of hours applied to the course topics for the two groups of students, the majority of undergraduates from biomedicine and medicine preferred metabolic topics. Although the perception of a medical student is expected to be different than that of a biomedical student, as the aims of the two programs are different, 92.4% of students from each course agreed or strongly agreed with the biochemistry topics, and 92.1% thought highly on this subject. The majority of students, a number of 139 undergraduates from biomedicine and 419 from medicine course, preferred traditional blackboard teaching than slide-projection, or power-point class. In conclusion, it is imperative that the health courses reflect on sophisticated technology and data presentation with high density of information in biochemistry discipline. The traditional classes with blackboard presentation were most favored by students from biomedicine and medicine courses. The use of students' preferred teaching techniques might turn biochemistry more easily understood for biomedical and medical students. © 2007 by The International Union of Biochemistry and Molecular Biology.
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Includes bibliography
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The relentless pursuit for materials containing rare earth ions with photoluminescent properties has led to several studies with applications in the development of new technologies. The main focus of this work is the preparation of Er3+-doped polycrystalline Y2O3 with photoluminescent properties using PEG as an organic precursor and heat-treated at different temperatures. The methodology used in this synthesis is highly attractive due to its high feasibility for improved technology and low cost for preparing materials. The behavior of the viscous resin has been evaluated and the final compounds exhibited the formation of a cubic polycrystalline phase, which is able to support variations in Er3+ doping concentrations up to 10 mol%, without significant changes in the polycrystalline parameters. The values of the nanocrystallite size calculated by Scherrer's equation showed direct dependence on the heat-treatment temperature as well as the Er3+ concentration. Intense emission in the visible region under excitation at 980 nm was attributed to an upconversion phenomenon assigned to the intraconfigurational f-f transitions of Er3+ ions. The upconversion mechanism was investigated and it was demonstrated that the higher intense emission in the red region in comparison to the emission in the green region is related to the crystallite size. The studies about the intensity showed the dependence of upconversion emission of power source, indicating that two-photon are responsible for the green and red photoluminescence. These polycrystalline materials exhibit properties that make them promising for use in solar energy systems, C-telecom band or solid-state laser devices. (C) 2014 Elsevier B.V. All rights reserved.