1,044 research outputs found

    Psychological principles of successful aging technologies: A mini-review

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    Based on resource-oriented conceptions of successful life-span development, we propose three principles for evaluating assistive technology: (a) net resource release; (b) person specificity, and (c) proximal versus distal frames of evaluation. We discuss how these general principles can aid the design and evaluation of assistive technology in adulthood and old age, and propose two technological strategies, one targeting sensorimotor and the other cognitive functioning. The sensorimotor strategy aims at releasing cognitive resources such as attention and working memory by reducing the cognitive demands of sensory or sensorimotor aspects of performance. The cognitive strategy attempts to provide adaptive and individualized cuing structures orienting the individual in time and space by providing prompts that connect properties of the environment to the individual's action goals. We argue that intelligent assistive technology continuously adjusts the balance between `environmental support' and `self-initiated processing' in person-specific and aging-sensitive ways, leading to enhanced allocation of cognitive resources. Furthermore, intelligent assistive technology may foster the generation of formerly latent cognitive resources by activating developmental reserves (plasticity). We conclude that `lifespan technology', if co-constructed by behavioral scientists, engineers, and aging individuals, offers great promise for improving both the transition from middle adulthood to old age and the degree of autonomy in old age in present and future generations. Copyright (C) 2008 S. Karger AG, Basel

    Conductance statistics from a large array of sub-10 nm molecular junctions

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    Devices made of few molecules constitute the miniaturization limit that both inorganic and organic-based electronics aspire to reach. However, integration of millions of molecular junctions with less than 100 molecules each has been a long technological challenge requiring well controlled nanometric electrodes. Here we report molecular junctions fabricated on a large array of sub-10 nm single crystal Au nanodots electrodes, a new approach that allows us to measure the conductance of up to a million of junctions in a single conducting Atomic Force Microscope (C-AFM) image. We observe two peaks of conductance for alkylthiol molecules. Tunneling decay constant (beta) for alkanethiols, is in the same range as previous studies. Energy position of molecular orbitals, obtained by transient voltage spectroscopy, varies from peak to peak, in correlation with conductance values.Comment: ACS Nano (in press

    Reaction-kinetics of organo-clay hybrid films: in-situ IRRAS and AFM studies

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    In this paper we have reported the reaction kinetics of nano dimensional clay saponite and hectorite with an amphiphilic cation octadecyl rhodamine B (RhB) in hybrid Langmuir monolayer at the air-water interface. The surface pressure-molecular area (pi-A) isotherms were strongly influenced by the presence of clay with the lift-off area of the cationic amphiphile shifted to progressively larger area. In-situ infrared reflection absorption spectroscopy (IRRAS) was used to demonstrate the reaction kinetics. Time taken to complete the reaction kinetics for RhB-hectorite hybrid films is larger than RhB-saponite hybrid films. Atomic force microscopic images of hybrid Langmuir-Blodgett films give compelling visual evidence of the incorporation of clay platelets into the hybrid films and density of which increases with the progress of reaction kinetics.Comment: 11 pages, 5 figure

    Theory of electrical rectification in a molecular monolayer

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    The current-voltage characteristics in Langmuir-Blodgett monolayers of \gamma-hexadecylquinolinium tricyanoquinodimethanide (C16H33Q-3CNQ) sandwiched between Al or Au electrodes is calculated, combining ab initio and self-consistent tight binding techniques. The rectification current depends on the position of the LUMO and HOMO relative to the Fermi levels of the electrodes as in the Aviram-Ratner mechanism, but also on the profile of the electrostatic potential which is extremely sensitive to where the electroactive part of the molecule lies in the monolayer. This second effect can produce rectification in the direction opposite to the Aviram-Ratner prediction

    High on-off conductance switching ratio in optically-driven self-assembled conjugated molecular systems

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    A new azobenzene-thiophene molecular switch is designed, synthesized and used to form self-assembled monolayers (SAM) on gold. An "on/off" conductance ratio up to 7x1E3 (with an average value of 1.5x1E3) is reported. The "on" conductance state is clearly identified to the cis isomer of the azobenzene moiety. The high "on/off" ratio is explained in terms of photo-induced, configuration-related, changes in the electrode-molecule interface energetics (changes in the energy position of the molecular orbitals with respect to the Fermi energy of electrodes) in addition to changes in the tunnel barrier length (length of the molecules). First principles DFT calculations demonstrate a better delocalization of the frontier orbitals, as well as a stronger electronic coupling between the azobenzene moiety and the electrode for the cis configuration over the trans one. Measured photoionization cross-sections for the molecules in the SAM are close to the known values for azobenzene derivatives in solution.Comment: 1 file with main text, figure and suppementary informatio

    Cardiac and Respiratory Patterns Synchronize between Persons during Choir Singing

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    Dyadic and collective activities requiring temporally coordinated action are likely to be associated with cardiac and respiratory patterns that synchronize within and between people. However, the extent and functional significance of cardiac and respiratory between-person couplings have not been investigated thus far. Here, we report interpersonal oscillatory couplings among eleven singers and one conductor engaged in choir singing. We find that: (a) phase synchronization both in respiration and heart rate variability increase significantly during singing relative to a rest condition; (b) phase synchronization is higher when singing in unison than when singing pieces with multiple voice parts; (c) directed coupling measures are consistent with the presence of causal effects of the conductor on the singers at high modulation frequencies; (d) the different voices of the choir are reflected in network analyses of cardiac and respiratory activity based on graph theory. Our results suggest that oscillatory coupling of cardiac and respiratory patterns provide a physiological basis for interpersonal action coordination

    Electrostatic-Assembly-Driven Formation of Supramolecular Rhombus Microparticles and Their Application for Fluorescent Nucleic Acid Detection

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    In this paper, we report on the large-scale formation of supramolecular rhombus microparticles (SRMs) driven by electrostatic assembly, carried out by direct mixing of an aqueous HAuCl4 solution and an ethanol solution of 4,4′-bipyridine at room temperature. We further demonstrate their use as an effective fluorescent sensing platform for nucleic acid detection with a high selectivity down to single-base mismatch. The general concept used in this approach is based on adsorption of the fluorescently labeled single-stranded DNA (ssDNA) probe by SRM, which is accompanied by substantial fluorescence quenching. In the following assay, specific hybridization with its target to form double-stranded DNA (dsDNA) results in desorption of ssDNA from SRM surface and subsequent fluorescence recovery

    "Give me some space" : exploring youth to parent aggression and violence

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    A small scale qualitative project, undertaken by an interdisciplinary domestic violence research group involving academic researchers and research assistants, with colleagues from Independent Domestic Abuse Services (IDAS), investigated youth aggression and violence against parents. Following the literature review, data was generated through several research conversations with young people (n = 2), through semi-structured interviews with mothers (n = 3) and practitioners (n = 5), and through a practitioner focus group (n = 8). Thematic analysis and triangulation of the data from parents, practitioners and young people, elicited interconnected and complex overarching themes. Young people could be both victim and perpetrator. The witnessing or experiencing of domestic aggression and violence raised the concept of ‘bystander children’. The impact of young people experiencing familial violence was underestimated by parents. For practitioners, the effects of working with domestic violence was shown to be significant - both positively and negatively

    Trajectories of Big Five Personality Traits: A Coordinated Analysis of 16 Longitudinal Samples

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    This study assessed change in self‐reported Big Five personality traits. We conducted a coordinated integrative data analysis using data from 16 longitudinal samples, comprising a total sample of over 60 000 participants. We coordinated models across multiple datasets and fit identical multi‐level growth models to assess and compare the extent of trait change over time. Quadratic change was assessed in a subset of samples with four or more measurement occasions. Across studies, the linear trajectory models revealed declines in conscientiousness, extraversion, and openness. Non‐linear models suggested late‐life increases in neuroticism. Meta‐analytic summaries indicated that the fixed effects of personality change are somewhat heterogeneous and that the variability in trait change is partially explained by sample age, country of origin, and personality measurement method. We also found mixed evidence for predictors of change, specifically for sex and baseline age. This study demonstrates the importance of coordinated conceptual replications for accelerating the accumulation of robust and reliable findings in the lifespan developmental psychological sciences. © 2020 European Association of Personality PsychologyPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/156004/1/per2259.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156004/2/per2259-sup-0001-Data_S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156004/3/per2259-sup-0002-Open_Practices_Disclosure_Form.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/156004/4/per2259_am.pd
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