2,492 research outputs found

    Perceptions of competence: Age moderates views of healthy aging and Alzheimerā€™s disease

    Get PDF
    Background/Study Context: Older adults have more complex and differentiated views of aging than do younger adults, but less is known about age-related perceptions of Alzheimerā€™s disease. This study investigated age-related perceptions of competence of an older adult labeled as ā€œin good healthā€ (healthy) or ā€œhas Alzheimerā€™s diseaseā€ (AD), using a person-perception paradigm. It was predicted that older adults would provide more differentiated assessments of the two targets than would younger adults.Methods: Younger (n = 86; 18ā€“36 years) and older (n = 66; 61ā€“95 years) adults rated activities of daily living (ADL), instrumental activities of daily living (IADL), and memory abilities of a female target aged 75 years, described as healthy or with AD. Data on anxiety about aging, knowledge of and experience with aging and AD, knowledge of memory aging, and positive and negative biases toward aging and AD were also collected.Results: Older adults perceived the healthy target as more capable of cognitively effortful activities (e.g., managing finances) and as possessing better memory abilities than the AD target. As predicted, these differences were greater than differences between targets perceived by younger adults. The interaction effect remained significant after statistically controlling for relevant variables, including education and gender. Additionally, exploratory analyses revealed that older adults held less positively biased views of AD than younger adults, but negatively biased views were equivalent between age groups.Conclusion: The results demonstrate that mere labels of ā€œhealthyā€ and ā€œAlzheimerā€™s diseaseā€ produce significant and subtle age differences in perceived competencies of older adults, and that biases towards AD vary by age group and valence. Our findings extend the person-perception paradigm to an integrative analysis of aging and AD, are consistent with models of adult development, and complement current research and theory on stereotypes of aging. Future directions for research on perceptions of aging are suggested

    Improved control of Trialeurodes vaporariorum using mixture combinations of entomopathogenic fungi and the chemical insecticide spiromesifen

    Get PDF
    Greenhouse whitefly (Trialeurodes vaporariorum) is a major global pest, causing direct damage to plants and transmitting viral plant diseases. Management of T. vaporariorum is problematic because of widespread pesticide resistance, and many greenhouse growers rely on biological control agents to regulate T. vaporariorum populations. However, these are often slow and vary in efficacy, leading to subsequent application of chemical insecticides when pest populations exceed threshold levels. Combining chemical and biological pesticides has great potential but can result in different outcomes, from positive to negative interactions. In this study, we evaluated co-applications of the entomopathogenic fungi (EPF) Beauveria bassiana and Cordyceps farinosa and the chemical insecticide spiromesifen in laboratory bioassays. Complex interactions between the EPFs and insecticide were described using an ecotoxicological mixtures model, the MixTox analysis. Depending on the EPF and chemical concentrations applied, mixtures resulted in additivity, synergism, or antagonism in terms of total whitefly mortality. Combinations of B. bassiana and spiromesifen, compared to single treatments, increased the rate of kill by 5 days. Results indicate the potential for combined applications of EPF and spiromesifen as an effective integrated pest management strategy and demonstrate the applicability of the MixTox model to describe complex mixture interactions

    Coupling high-frequency stream metabolism and nutrient monitoring to explore biogeochemical controls on downstream nitrate delivery

    Get PDF
    Instream biogeochemical process measurements are often short-term and localized. Here we use in situ sensors to quantify the net effects of biogeochemical processes on seasonal patterns in baseflow nitrate retention at the river-reach scale. Dual-station high-frequency in situ nitrate measurements, were coupled with high-frequency measurements of stream metabolism and dissolved inorganic carbon, in a tributary of the Buffalo National River, Arkansas. Nitrate assimilation was calculated from net primary production, and combined with mass-balance measurements, to estimate net nitrification and denitrification. The combined net effects of these instream processes (assimilation, denitrification, and nitrification) removed >30ā€“90% of the baseflow nitrate load along a 6.5 km reach. Assimilation of nitrate by photoautotrophs during spring and early summer was buffered by net nitrification. Net nitrification peaked during the spring. After midsummer, there was a pronounced switch from assimilatory nitrate uptake to denitrification. There was clear synchronicity between the switch from nitrate assimilation to denitrification, a reduction in river baseflows, and a shift in stream metabolism from autotrophy to heterotrophy. The results show how instream nitrate retention and downstream delivery is driven by seasonal shifts in metabolic pathways; and how continuous in situ stream sensor networks offer new opportunities for quantifying the role of stream biota in the dynamics, fate, and transport of nitrogen in fluvial systems

    Interactive effects of temperature and nitrogen on the physiology of kelps (Nereocystis luetkeana and Saccharina latissima)

    Get PDF
    Kelp forest declines have been linked to warming ocean temperatures worldwide. Ocean warming rarely occurs in isolation, so multiple stressor studies are necessary to understand the physiological responses of kelp to climate change. The canopy-forming bull kelp, Nereocystis luetkeana, is going locally extinct in areas of the Salish Sea that are seasonally warm and nutrient poor, while the understory kelp, Saccharina latissima, persists at those sites. Further, nitrogen availability can alter physiological responses of kelps to temperature stress, including alleviating warming stress. We compared the physiological responses of kelp sporophytes to high temperature stress and nitrogen limitation between two populations of N. luetkeana with different environmental histories (warm and nutrient poor vs. cold and nutrient rich) and between two species, N. luetkeana and S. latissima. Using laboratory mesocosms, we tested the interactive effects of short term (8-9 day) exposure of kelp blades to different temperatures: low (9, 13Ā°C), moderate (15, 16Ā°C), and warm (21Ā°C) at two different nitrogen concentrations: low (1-3 Ī¼M) vs. high (>10 Ī¼M). We examined a wide array of physiological responses: blade growth, photosynthesis, respiration, photosynthetic yield, nutrient uptake, and tissue C:N. Both kelp species responded negatively to elevated temperatures, but not to low nitrogen levels. Blades of both species showed signs of metabolic stress and reduced growth in the warmest temperature treatment (21Ā°C), at both high and low nitrogen levels, suggesting that N. luetkeana and S. latissima are susceptible to thermal stress over short time periods. Populations of N. luetkeana from warm, nutrient poor and cool, nutrient rich areas were equally susceptible to the effects of ocean warming. Our results suggest that nutrient additions may actually reduce kelp performance at supra-optimal temperatures, and a thorough understanding of kelp responses to coastal temperature and nutrient dynamics is needed to guide conservation and restoration actions

    Nearshore subtidal community response during and after sediment disturbance associated with dam removal

    Get PDF
    Dam removal is used increasingly to restore aquatic ecosystems and remove unnecessary or high-risk infrastructure. As the number of removals increases, there is a growing understanding about the hydrologic, geomorphic, and ecological responses to these removals. Most dam removal studies, however, focus on river and watershed responses to dam removal. The removal of two dams on the Elwha River provided a unique opportunity to characterize the response of nearshore (coastal) ecosystems. We conducted SCUBA surveys between 2011 and 2022 to quantify trajectories of change in a nearshore ecosystem during and after dam removal. We focused on the degree to which the abundances of kelp, benthic invertebrates, and fish changed in response to patterns of sediment fluxes during and after dam removal. Our findings point to two pathways of response depending on the disturbance mechanism and species type. Sites with persistent sediment deposition were characterized by wholesale community changes that did not recover to a before dam removal condition. Instead, the sites were colonized by new species that were largely absent prior to dam removal. Sites that experienced high turbidity but lacked persistent seafloor deposition were primarily characterized by a reduction in the abundance of kelp and other algae during dam removal and a rapid recovery after sediment flux to the nearshore declined. Dam removal influences on invertebrates and fish at these sites were more variable, benefiting some species and disadvantaging others. In addition to dam removal, sea star wasting syndrome and a marine heatwave exerted distinct controls on subtidal communities during the same period. The loss of the predatory sea star Pycnopodia helianthoides was associated with gains in some of its prey species, and kelp community changes reflected regional trends in ocean temperature and kelp abundance. The results presented here have important implications for understanding the response of marine ecosystems to future dam removals and similar sediment perturbation events

    Development and preliminary validation of the 'Caring for Country' questionnaire: measurement of an Indigenous Australian health determinant

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>'Caring for Country' is defined as Indigenous participation in interrelated activities with the objective of promoting ecological and human health. Ecological services on Indigenous-owned lands are belatedly attracting some institutional investment. However, the health outcomes associated with Indigenous participation in 'caring for country' activities have never been investigated. The aims of this study were to pilot and validate a questionnaire measuring caring for country as an Indigenous health determinant and to relate it to an external reference, obesity.</p> <p>Methods</p> <p>Purposively sampled participants were 301 Indigenous adults aged 15 to 54 years, recruited during a cross-sectional program of preventive health checks in a remote Australian community. Questionnaire validation was undertaken with psychometric tests of internal consistency, reliability, exploratory factor analysis and confirmatory one-factor congeneric modelling. Accurate item weightings were derived from the model and used to create a single weighted composite score for caring for country. Multiple linear regression modelling was used to test associations between the caring for country score and body mass index adjusting for socio-demographic factors and health behaviours.</p> <p>Results</p> <p>The questionnaire demonstrated adequate internal consistency, test-retest validity and proxy-respondent validity. Exploratory factor analysis of the 'caring for country' items produced a single factor solution that was confirmed via one-factor congeneric modelling. A significant and substantial association between greater participation in caring for country activities and lower body mass index was demonstrated. Adjusting for socio-demographic factors and health behaviours, an inter-quartile range rise in caring for country scores was associated with 6.1 Kg and 5.3 Kg less body weight for non-pregnant women and men respectively.</p> <p>Conclusion</p> <p>This study indicates preliminary support for the validity of the caring for country concept and a questionnaire designed to measure it. This study also highlights the importance of investigating Indigenous-asserted health promotion activities. Further studies in similar populations are merited to test the generalisability of this questionnaire and to explore associations with other important Indigenous health outcomes.</p

    The digital mundane, social media and the military

    Get PDF
    This article draws on empirical data with British military personnel in order to investigate what we call the digital mundane in military life. We argue that social media and smartphone technologies within the military offer a unique environment in which to investigate the ways individualā€™s position themselves within certain axes of institutional and cultural identities. At the same time, the convolutions, mediatory practices, and mundane social media rituals that service personnel employ through their smartphones resonates widely with, for example, youth culture, digital mobile cultures. Together they suggest complex mediations with social and mobile media, that draws on, and extends non-military practice into new (and increasingly normative) terrains

    Cancer Variant Interpretation Group UK (CanVIG-UK): an exemplar national subspecialty multidisciplinary network.

    Get PDF
    Advances in technology have led to a massive expansion in the capacity for genomic analysis, with a commensurate fall in costs. The clinical indications for genomic testing have evolved markedly; the volume of clinical sequencing has increased dramatically; and the range of clinical professionals involved in the process has broadened. There is general acceptance that our early dichotomous paradigms of variants being pathogenic-high risk and benign-no risk are overly simplistic. There is increasing recognition that the clinical interpretation of genomic data requires significant expertise in disease-gene-variant associations specific to each disease area. Inaccurate interpretation can lead to clinical mismanagement, inconsistent information within families and misdirection of resources. It is for this reason that 'national subspecialist multidisciplinary meetings' (MDMs) for genomic interpretation have been articulated as key for the new NHS Genomic Medicine Service, of which Cancer Variant Interpretation Group UK (CanVIG-UK) is an early exemplar. CanVIG-UK was established in 2017 and now has >100 UK members, including at least one clinical diagnostic scientist and one clinical cancer geneticist from each of the 25 regional molecular genetics laboratories of the UK and Ireland. Through CanVIG-UK, we have established national consensus around variant interpretation for cancer susceptibility genes via monthly national teleconferenced MDMs and collaborative data sharing using a secure online portal. We describe here the activities of CanVIG-UK, including exemplar outputs and feedback from the membership
    • ā€¦
    corecore