66 research outputs found

    The Ames Vertical Gun Range

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    The Ames Vertical Gun Range (AVGR) is a national facility for conducting laboratory- scale investigations of high-speed impact processes. It provides a set of light-gas, powder, and compressed gas guns capable of accelerating projectiles to speeds up to 7 km s(exp -1). The AVGR has a unique capability to vary the angle between the projectile-launch and gravity vectors between 0 and 90 deg. The target resides in a large chamber (diameter approximately 2.5 m) that can be held at vacuum or filled with an experiment-specific atmosphere. The chamber provides a number of viewing ports and feed-throughs for data, power, and fluids. Impacts are observed via high-speed digital cameras along with investigation-specific instrumentation, such as spectrometers. Use of the range is available via grant proposals through any Planetary Science Research Program element of the NASA Research Opportunities in Space and Earth Sciences (ROSES) calls. Exploratory experiments (one to two days) are additionally possible in order to develop a new proposal

    Environmental volunteer well-being: managers’ perception and actual well-being of volunteers

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    Environmental volunteering is known to be able to increase well-being but environmental volunteer well-being has rarely been compared to participant well-being associated with other types of volunteering or nature-based activities. This paper aims to use a multidimensional approach to well-being to explore the immediately experienced and later remembered well-being of environmental volunteers and to compare this to the increased well-being of participants in other types of nature-based activities and volunteering. Furthermore, it aims to compare volunteer managers’ perception of their volunteers’ well-being with the self-reported well-being of the volunteers. Onsite surveys were conducted of practical conservation and biodiversity monitoring volunteers as well as their control groups, walkers and fieldwork students, respectively, to measure general well-being before their nature-based activity and activity-related well-being immediately after their activity. Online surveys of current, former and potential volunteers and volunteer managers in environmental volunteering and other types of volunteering measured remembered volunteering-related well-being and volunteer managers’ perceptions of their volunteers’ well-being. Data were analysed based on Seligman’s multidimensional PERMA (‘Positive emotion’, ‘Engagement’, ‘positive Relationship’, ‘Meaning’, ‘Achievement’) model of well-being. Factor analysis recovered three of the five PERMA elements, ‘engagement’, ‘relationship’ and ‘meaning’, as well as ‘negative emotion’ and ‘health’ as factors. Environmental volunteering significantly improved positive elements and significantly decreased negative elements of participants’ immediate well-being and it did so more than walking or student fieldwork did. Even remembering their volunteering up to six months later, volunteers rated their volunteering-related well-being higher than volunteers rated their well-being generally in life. However, volunteering was not found to have an effect on overall mean well-being generally in life. Volunteer managers did not perceive the significant increase in well-being that volunteers reported during volunteering. Multidimensional well-being assessments offer the potential for volunteer organisations and managers to more systematically understand, support and enhance volunteer well-being

    The Latent Structure of Autistic Traits:A Taxometric, Latent Class and Latent Profile Analysis of the Adult Autism Spectrum Quotient

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    Autistic traits are widely thought to operate along a continuum. A taxometric analysis of Adult Autism Spectrum Quotient data was conducted to test this assumption, finding little support but identifying a high severity taxon. To understand this further, latent class and latent profile models were estimated that indicated the presence of six distinct subtypes: one with little probability of endorsing any autistic traits, one engaging in ‘systemising’ behaviours, three groups endorsing multiple components of Wing and Gould’s autistic triad, and a group similar in size and profile to the taxon previously identified. These analyses suggest the AQ (and potentially by extension autistic traits) have a categorical structure. These findings have important implications for the analysis and interpretation of AQ data

    Comprehensive geriatric assessment, multifactorial interventions and nurse-led care coordination to prevent functional decline in community-dwelling older persons: protocol of a cluster randomized trial

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    <p>Abstract</p> <p>Background</p> <p>Functional decline in community-dwelling older persons is associated with the loss of independence, the need for hospital and nursing-home care and premature death. The effectiveness of multifactorial interventions in preventing functional decline remains controversial. The aim of this study is to investigate whether functional decline in community-dwelling older persons can be delayed or prevented by a comprehensive geriatric assessment, multifactorial interventions and nurse-led care coordination.</p> <p>Methods/Design</p> <p>In a cluster randomized controlled trial, with the general practice as the unit of randomization, 1281 participants from 25 general practices will be enrolled in each condition to compare the intervention with usual care. The intervention will focus on older persons who are at increased risk for functional decline, identified by an Identification of Seniors at Risk Primary Care (ISAR-PC) score (≥ 2). These older persons will receive a comprehensive geriatric assessment, an individually tailored care and treatment plan, consisting of multifactorial, evidence-based interventions and subsequent nurse-led care coordination. The control group will receive 'care as usual' by the general practitioner (GP). The main outcome after 12 months is the level of physical functioning on the modified Katz-15 index score. The secondary outcomes are health-related quality of life, psychological and social functioning, healthcare utilization and institutionalization. Furthermore, a process evaluation and cost-effectiveness analysis will be performed.</p> <p>Discussion</p> <p>This study will provide new knowledge regarding the effectiveness and feasibility of a comprehensive geriatric assessment, multifactorial interventions and nurse-led elderly care in general practice.</p> <p>Trial registration</p> <p><a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2653">NTR2653</a></p> <p>Grant</p> <p>Unrestricted grant 'The Netherlands Organisation for Health Research and development' no 313020201</p

    Implementing the chronic care model for frail older adults in the Netherlands: study protocol of ACT (frail older adults: care in transition)

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    <p>Abstract</p> <p>Background</p> <p>Care for older adults is facing a number of challenges: health problems are not consistently identified at a timely stage, older adults report a lack of autonomy in their care process, and care systems are often confronted with the need for better coordination between health care professionals. We aim to address these challenges by introducing the geriatric care model, based on the chronic care model, and to evaluate its effects on the quality of life of community-dwelling frail older adults.</p> <p>Methods/design</p> <p>In a 2-year stepped-wedge cluster randomised clinical trial with 6-monthly measurements, the chronic care model will be compared with usual care. The trial will be carried out among 35 primary care practices in two regions in the Netherlands. Per region, practices will be randomly allocated to four allocation arms designating the starting point of the intervention. <it>Participants</it>: 1200 community-dwelling older adults aged 65 or over and their primary informal caregivers. Primary care physicians will identify frail individuals based on a composite definition of frailty and a polypharmacy criterion. Final inclusion criterion: scoring 3 or more on a disability case-finding tool. <it>Intervention</it>: Every 6 months patients will receive a geriatric in-home assessment by a practice nurse, followed by a tailored care plan. Expert teams will manage and train practice nurses. Patients with complex care needs will be reviewed in interdisciplinary consultations. <it>Evaluation</it>: We will perform an effect evaluation, an economic evaluation, and a process evaluation. Primary outcome is quality of life as measured with the Short Form-12 questionnaire. Effect analyses will be based on the “intention-to-treat” principle, using multilevel regression analysis. Cost measurements will be administered continually during the study period. A cost-effectiveness analysis and cost-utility analysis will be conducted comparing mean total costs to functional status, care needs and QALYs. We will investigate the level of implementation, barriers and facilitators to successful implementation and the extent to which the intervention manages to achieve the transition necessary to overcome challenges in elderly care.</p> <p>Discussion</p> <p>This is one of the first studies assessing the effectiveness, cost-effectiveness and implementation process of the chronic care model for frail community-dwelling older adults.</p> <p>Trial registration</p> <p>The Netherlands National Trial Register NTR2160.</p

    Psychometric Evaluation of the Altered States of Consciousness Rating Scale (OAV)

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    BACKGROUND: The OAV questionnaire has been developed to integrate research on altered states of consciousness (ASC). It measures three primary and one secondary dimensions of ASC that are hypothesized to be invariant across ASC induction methods. The OAV rating scale has been in use for more than 20 years and applied internationally in a broad range of research fields, yet its factorial structure has never been tested by structural equation modeling techniques and its psychometric properties have never been examined in large samples of experimentally induced ASC. METHODOLOGY/PRINCIPAL FINDINGS: The present study conducted a psychometric evaluation of the OAV in a sample of psilocybin (n = 327), ketamine (n = 162), and MDMA (n = 102) induced ASC that was obtained by pooling data from 43 experimental studies. The factorial structure was examined by confirmatory factor analysis, exploratory structural equation modeling, hierarchical item clustering (ICLUST), and multiple indicators multiple causes (MIMIC) modeling. The originally proposed model did not fit the data well even if zero-constraints on non-target factor loadings and residual correlations were relaxed. Furthermore, ICLUST suggested that the "oceanic boundlessness" and "visionary restructuralization" factors could be combined on a high level of the construct hierarchy. However, because these factors were multidimensional, we extracted and examined 11 new lower order factors. MIMIC modeling indicated that these factors were highly measurement invariant across drugs, settings, questionnaire versions, and sexes. The new factors were also demonstrated to have improved homogeneities, satisfactory reliabilities, discriminant and convergent validities, and to differentiate well among the three drug groups. CONCLUSIONS/SIGNIFICANCE: The original scales of the OAV were shown to be multidimensional constructs. Eleven new lower order scales were constructed and demonstrated to have desirable psychometric properties. The new lower order scales are most likely better suited to assess drug induced ASC

    Decisional and emotional forgiveness scales: Psychometric validity and correlates with personality and vengeance.

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    Forgiveness is an internal process to overcome negative aspects (e.g., anger, bitterness, resentment) towards an offender, being associated to a range of variables (e.g., well-being, quality of loving relationships, resilience). Forgiveness can happen through two different types: (1) decisional, which is a behavioural modification to reduce direct hostility; and (2) emotional, which is a transformation of negative emotions into positive. The current research aimed to gather psychometric evidences for the Decisional Forgiveness Scale (DFS) and the Emotional Forgiveness Scale (EFS), using a Brazilian sample. Two studies were conducted. In Study 1 (n = 181), the bifactorial structures were replicated, also providing satisfactory reliability levels. Through Item Response Theory, results indicated good discrimination, difficulty levels, and considerable information to all the items from both measures. In Study 2 (n = 220), confirmatory factor analyses confirmed their structure, presenting good model fit. The measures were also invariant regarding participants’ gender. Finally, the measures presented significant results when correlated to personality and vengeance. In sum, the instruments demonstrated satisfactory psychometric properties, evidencing the possibility of their use in the respective context.The authors acknowledge financial support from the CAPES Foundation (Brazil, http://www.capes.gov.br/) for the Ph.D. scholarship to the second author. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Bone substitutes in orthopaedic surgery: from basic science to clinical practice

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