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1.
ACS Catal ; 14(9): 6749-6798, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38721380

RESUMEN

Thermal approaches have played a dominant role in driving chemical reactions within the chemicals and fuels industries, benefiting from ongoing enhancements in efficiency via heat integration, catalyst development, and process intensification. Nevertheless, these traditional thermal approaches remain heavily reliant on fossil fuels, and there exists an urgent demand for the implementation of renewable energy technologies to synthesize fuels, commodity chemicals, and specialty chemicals. Nonthermal plasmas have gained considerable attention in recent years as a promising solution, and the prospects of combining plasmas with suitable catalysts have become even more appealing. Moreover, the evolution of nonthermal plasma catalysis approaches for the generation of clean hydrogen could be transformative in reducing greenhouse gas emissions. This comprehensive review highlights the influential contributions in plasma catalysis for hydrogen production, discusses recent advancements, and provides future prospects for researchers aiming to advance the production of clean hydrogen.

2.
Int J Circumpolar Health ; 83(1): 2309756, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38290014

RESUMEN

In very cold environments, it may be burdensome or impossible for the polar medic to prevent medicines from freezing. We sought to investigate whether orientation affected the risk that glass ampoules of 1 in 1000 adrenaline, an important emergency drug, would break during freezing and subsequent thawing. Ampoules of adrenaline were orientated either upright, horizontally or inverted. They were exposed to freezing temperatures (-25°C or -80°C) and then allowed to thaw. A crossover design was used whereby the orientation of unbroken ampoules was changed for the next trial. No ampoules broke when frozen at -25°C and then thawed. When this was repeated at -80°C, ampoules reliably broke unless they were upright with no liquid in the top part of the ampoule. Upright orientation prevents the breakage of glass ampoules of 1 in 1000 adrenaline rapidly frozen at -80°C. The polar medic may consider storing ampoules upright if they are to be exposed to very low temperatures.


Asunto(s)
Epinefrina , Vidrio , Humanos , Temperatura , Congelación
3.
Memory ; 31(5): 665-677, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36945870

RESUMEN

Prospective memory (PM) - memory for future intentions - has a core term called focality which describes how closely a PM task relates to an ongoing task. When a close relationship exists between an ongoing and PM task, the task is classified as focal (loose relationships are classified as nonfocal). Competing PM theories differ primarily in explanations for how focality changes participants' approaches. Researchers classify PM intentions as focal or nonfocal in two ways: (1) task appropriateness, congruency (TAP) or incongruency (TIP) of processing to complete both tasks, and (2) cue specificity, specific or general task cues. Independently manipulating this ambiguity in defining "focality" was our current focus. Participants were randomly assigned to a control group, a focal PM condition, or one of three nonfocal conditions. Their ongoing task involved a semantic judgment (Experiment 1) or an orthographic judgment (Experiment 2). Cue specificity impacted PM accuracy consistently, favouring specific cues. Task-appropriateness impacted PM accuracy in Experiment 1, but not in Experiment 2 which showed protective effects for specific, whole-word PM cues - emphasizing the role that deeper processing has on PM success. These studies highlight the ambiguity in the operational definition of focality and provide the groundwork for continued refinement of the definition.


Asunto(s)
Señales (Psicología) , Memoria Episódica , Humanos , Tiempo de Reacción , Trastornos de la Memoria , Semántica
4.
ACS Eng Au ; 2(6): 535-546, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36573176

RESUMEN

Plasma-surface coupling has emerged as a promising approach to perform chemical transformations under mild conditions that are otherwise difficult or impossible thermally. However, a few examples of inexpensive and accessible in situ/operando techniques exist for observing plasma-solid interactions, which has prevented a thorough understanding of underlying surface mechanisms. Here, we provide a simple and adaptable design for a dielectric barrier discharge (DBD) plasma cell capable of interfacing with Fourier transform infrared spectroscopy (FTIR), optical emission spectroscopy (OES), and mass spectrometry (MS) to simultaneously characterize the surface, the plasma phase, and the gas phase, respectively. The system was demonstrated using two example applications: (1) plasma oxidation of primary amine functionalized SBA-15 and (2) catalytic low temperature nitrogen oxidation. The results from application (1) provided direct evidence of a 1% O2/He plasma interacting with the aminosilica surface by selective oxidation of the amino groups to nitro groups without altering the alkyl tether. Application (2) was used to detect the evolution of NOX species bound to both platinum and silica surfaces under plasma stimulation. Together, the experimental results showcase the breadth of possible applications for this device and confirm its potential as an essential tool for conducting research on plasma-surface coupling.

5.
J Cardiovasc Magn Reson ; 24(1): 2, 2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34980185

RESUMEN

BACKGROUND: Despite the growing utility of cardiovascular magnetic resonance (CMR) for cardiac morphology and function, sex and age-specific normal reference values derived from large, multi-ethnic data sets are lacking. Furthermore, most available studies use a simplified tracing methodology. Using a large cohort of participants without history of cardiovascular disease (CVD) or risk factors from the Canadian Alliance for Healthy Heart and Minds, we sought to establish a robust set of reference values for ventricular and atrial parameters using an anatomically correct contouring method, and to determine the influence of age and sex on ventricular parameters. METHODS AND RESULTS: Participants (n = 3206, 65% females; age 55.2 ± 8.4 years for females and 55.1 ± 8.8 years for men) underwent CMR using standard methods for quantitative measurements of cardiac parameters. Normal ventricular and atrial reference values are provided: (1) for males and females, (2) stratified by four age categories, and (3) for different races/ethnicities. Values are reported as absolute, indexed to body surface area, or height. Ventricular volumes and mass were significantly larger for males than females (p < 0.001). Ventricular ejection fraction was significantly diminished in males as compared to females (p < 0.001). Indexed left ventricular (LV) end-systolic, end-diastolic volumes, mass and right ventricular (RV) parameters significantly decreased as age increased for both sexes (p < 0.001). For females, but not men, mean LV and RVEF significantly increased with age (p < 0.001). CONCLUSION: Using anatomically correct contouring methodology, we provide accurate sex and age-specific normal reference values for CMR parameters derived from the largest, multi-ethnic population free of CVD to date. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02220582. Registered 20 August 2014-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02220582 .


Asunto(s)
Ventrículos Cardíacos , Función Ventricular Izquierda , Factores de Edad , Canadá , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Imagen por Resonancia Cinemagnética , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Valores de Referencia , Factores Sexuales , Volumen Sistólico
6.
Mem Cognit ; 50(1): 112-128, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34184211

RESUMEN

Remembering to fulfill an intention at a later time often requires people to monitor the environment for cues that it is time to act. This monitoring involves the strategic allocation of attentional resources, ramping attention up more in some contexts than others. In addition to interfering with ongoing task performance, flexibly shifting attention may affect whether task-irrelevant information is later remembered. In the present investigation, we manipulated contextual expectations in event-related prospective memory (PM) to examine the consequences of flexible attention allocation on incidental memory. Across two experiments, participants completed a color-matching task while monitoring for ill-defined (Experiment 1) or specific (Experiment 2) PM targets. To manipulate contextual expectations, some participants were explicitly told about the trial types in which PM targets could (or not) appear, while others were given less precise or no expectations. Across experiments, participants' color-matching decisions were slower in high-expectation trials, relative to trials when targets were not expected. Additionally, participants had better incidental memory for PM-irrelevant items from high-expectation trials, but only when they received explicit contextual expectations. These results confirm that participants flexibly allocate attention based on explicit trial-by-trial expectations. Furthermore, the present study indicates that greater attention to item identity yields better incidental memory even for PM-irrelevant items, irrespective of processing time.


Asunto(s)
Memoria Episódica , Señales (Psicología) , Humanos , Intención , Recuerdo Mental , Análisis y Desempeño de Tareas
7.
Chem Commun (Camb) ; 57(100): 13772-13775, 2021 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-34860217

RESUMEN

Oligomerization of light olefins has become an essential step to convert gaseous olefins to liquid fuels and value-added chemicals. Here, we report the synthesis and application of nickel single sites isolated on Wells Dawson polyoxometalate defects as stable and regenerable catalysts for ethylene oligomerization.

8.
Neurology ; 97(17): e1707-e1716, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34504021

RESUMEN

BACKGROUND AND OBJECTIVES: To determine whether cognitive reserve attenuates the association of vascular brain injury with cognition. METHODS: Cross-sectional data were analyzed from 2 harmonized studies: the Canadian Alliance for Healthy Hearts and Healthy Minds (CAHHM) and the Prospective Urban and Rural Epidemiology (PURE) study. Markers of cognitive reserve were education, involvement in social activities, marital status, height, and leisure physical activity, which were combined into a composite score. Vascular brain injury was defined as nonlacunar brain infarcts or high white matter hyperintensity (WMH) burden on MRI. Cognition was assessed using the Montreal Cognitive Assessment Tool (MoCA) and the Digit Symbol Substitution Test (DSST). RESULTS: There were 10,916 participants age 35-81. Mean age was 58.8 years (range 35-81) and 55.8% were female. Education, moderate leisure physical activity, being in a marital partnership, being taller, and participating in social groups were each independently associated with higher cognition, as was the composite cognitive reserve score. Vascular brain injury was associated with lower cognition (ß -0.35 [95% confidence interval [CI] -0.53 to -0.17] for MoCA and ß -2.19 [95% CI -3.22 to -1.15] for DSST) but the association was not modified by the composite cognitive reserve variable (interaction p = 0.59 for MoCA and p = 0.72 for DSST). CONCLUSIONS: Both vascular brain injury and markers of cognitive reserve are associated with cognition. However, the effects were independent such that the adverse effects of covert vascular brain injury were not attenuated by higher cognitive reserve. To improve cognitive brain health, interventions to both prevent cerebrovascular disease and promote positive lifestyles are needed.


Asunto(s)
Infarto Encefálico/complicaciones , Cognición/fisiología , Reserva Cognitiva/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/fisiopatología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Mem Cognit ; 49(8): 1555-1567, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33959893

RESUMEN

Although false memories have largely been examined with the Deese-Roediger-McDermott (DRM) paradigm, little research has focused on the semantic context in which associates are encoded. Across three experiments, we varied semantic context during a sentence-processing task with DRM associates embedded within sentences. More meaningful sentences resulted in greater memory errors (Experiment 1). Furthermore, providing contextual information to discriminate old from new items did not reduce false alarms relative to encoding words in isolation when sentences converged on the meaning of the critical lure (Experiment 2), and actually increased memory errors (Experiment 3). These results suggest that semantic context that allows for meaningful relational processing of items within-lists and that converge on the semantic meaning of the critical lure increases the likelihood that the list theme is identified, resulting in more errors at test.


Asunto(s)
Recuerdo Mental , Semántica , Humanos , Memoria , Probabilidad , Represión Psicológica
10.
Appl Radiat Isot ; 167: 109491, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33121893

RESUMEN

Arsenic is a toxic metalloid which has been associated with a wide range of health effects in humans including skin abnormalities and an elevated risk of skin, bladder, kidney, and lung cancer, diabetes, and cardiovascular disease. The measurement of arsenic concentration in nail clippings is often used in population studies as an indicator of arsenic exposure. Portable X-ray fluorescence (XRF) is an emerging technique for measuring arsenic in nail clippings. In the current study, single toenail clippings from 60 Atlantic Canadian participants were assessed for arsenic using a new portable XRF approach. A mono-energetic portable XRF system using doubly curved crystal optics was used to measure each clipping for a total of 900 s. Energy spectra from each clipping were analyzed for arsenic characteristic X-rays to provide a normalized arsenic signal. The same clippings were then analyzed for arsenic concentration using a "gold standard" method of inductively coupled plasma mass spectrometry (ICP-MS). Nail clipping arsenic concentrations measured by ICP-MS ranged from 0.030 µg/g to 2.57 µg/g, with a median result of 0.14 µg/g. Portable XRF results for arsenic were compared against ICP-MS arsenic concentrations, with a linear equation of best fit determined between the two variables. A correlation coefficient of r = 0.77 was found from the 59 nail clippings returning an ICP-MS arsenic concentration above the limit of quantitation. When the comparison was limited to the 20 clippings having an XRF normalized signal at least twice as large as the associated uncertainty of measurement, the correlation coefficient was r = 0.89. With the selection of an arsenic concentration of 0.1 µg/g as a cut-off value between "exposed" and "non-exposed" individuals, the XRF method provided a test sensitivity of 76% and a specificity of 81%. The corresponding positive predictive value was 88% and the negative predictive value was 65%. The portable XRF technique used in this study shows promise as a means of assessing arsenic concentration in toenail clippings.


Asunto(s)
Arsénico/análisis , Uñas/química , Espectrometría por Rayos X/métodos , Calibración , Humanos
11.
J Clin Endocrinol Metab ; 106(2): e891-e898, 2021 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-33165530

RESUMEN

BACKGROUND: Diabetes is a risk factor for cerebrovascular disease and cognitive impairment. The anatomical basis for this is uncertain. METHODS: The Canadian Alliance for Healthy Hearts and Minds collected brain and carotid magnetic resonance imaging (MRI) and 2 cognitive tests (the Digit Symbol Substitution Test and the Montreal Cognitive Assessment test) in a cross-sectional sample of men and women. Brain MRIs identified brain infarcts (BI), lacunar BI, high white matter hyperintensity (WMH), vascular brain injury (VBI; BI or high WMH), and small vessel VBI (lacunar BI or high WMH). Carotid MRIs estimated carotid wall volume, a measure of subclinical atherosclerosis. Cognitive scores were standardized to each site's mean score, and cognitive impairment was identified by 1 or both test scores ≤1 standard deviation below the site's mean score on that test. RESULTS: The 7733 participants included 495 participants (6.4%) with diabetes, of whom 388 were taking diabetes drugs. After age and sex adjustment, diabetes was independently associated with BI (odds ratio [OR] 1.53, 95% confidence interval [CI] 1.05, 2.24), VBI (OR 1.64, 95% CI 1.26, 2.13), small vessel VBI (OR 1.67, 95% CI 1.28, 2.19), and cognitive impairment (OR 1.47, 95% CI 1.20, 1.80). The association between diabetes and small vessel VBI persisted after adjustment for cerebrovascular disease risk factors and nonlacunar infarcts (OR 1.52, 95% CI 1.15, 2.01), and the association with cognitive impairment persisted after adjustment for small vessel VBI (OR 1.27, 95% CI 1.03, 1.56). CONCLUSION: Small vessel disease characterizes much of the relationship between diabetes and VBI. However, additional factors are required to disentangle the relationship between diabetes and cognitive impairment.


Asunto(s)
Infarto Encefálico/epidemiología , Trastornos Cerebrovasculares/epidemiología , Disfunción Cognitiva/epidemiología , Diabetes Mellitus/epidemiología , Adulto , Anciano , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Infarto Encefálico/diagnóstico , Infarto Encefálico/etiología , Canadá/epidemiología , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/etiología , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Estudios Transversales , Diabetes Mellitus/diagnóstico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Microcirculación/fisiología , Persona de Mediana Edad , Neuroimagen , Pruebas Neuropsicológicas , Prevalencia , Factores de Riesgo
12.
CJC Open ; 2(6): 599-609, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33305220

RESUMEN

BACKGROUND: The intent of the Canadian Alliance for Healthy Hearts and Minds (CAHHM) cohort is to understand the early determinants of subclinical cardiac and vascular disease and progression in adults selected from existing cohorts-the Canadian Partnership for Tomorrow's Health, the Prospective Urban and Rural Evaluation (PURE) cohort, and the Montreal Heart Institute Biobank. We evaluated how well the CAHHM-Health Services Research (CAHHM-HSR) subcohort reflects the Canadian population. METHODS: A cross-sectional design was used among a prospective cohort of community-dwelling adults aged 35-69 years who met the CAHHM inclusion criteria, and a cohort of adults aged 35-69 years who responded to the 2015 Canadian Community Health Survey-Rapid Response module. The INTERHEART risk score was calculated at the individual level with means and proportions reported at the overall and provincial level. RESULTS: There are modest differences between CAHHM-HSR study participants and the 2015 Canadian Community Health Survey-Rapid Response respondents in age (56.3 vs 51.7 mean years), proportion of men (44.9% vs 49.3%), and mean INTERHEART risk score (9.7 vs 10.1). Larger differences were observed in postsecondary education (86.8% vs 70.2%), Chinese ethnicity (11.0% vs 3.3%), obesity (23.2% vs 29.3%), current smoker status (6.1% vs 18.4%), and having no cardiac testing (30.4% vs 55.9%). CONCLUSIONS: CAHHM-HSR participants are older, of higher socioeconomic status, and have a similar mean INTERHEART risk score, compared with participants in the Canadian Community Health Survey. Differing sampling strategies and missing data may explain some differences between the CAHHM-HSR cohort and Canadian community-dwelling adults and should be considered when using the CAHHM-HSR for scientific research.


CONTEXTE: L'étude Alliance canadienne cœurs et cerveaux sains (CAHHM) vise à mieux comprendre les facteurs déterminants précoces et la progression de l'atteinte cardiovasculaire subclinique chez des adultes sélectionnés au sein de cohortes existantes ­ soit celles de l'étude menée par le Partenariat canadien pour la santé de demain, de l'étude PURE (Prospective Urban and Rural Evaluation) et de la biobanque de l'Institut de cardiologie de Montréal. Nous avons évalué la mesure dans laquelle la sous-cohorte du volet de recherche sur l'utilisation des services de santé de la CAHHM (CAHHM-HSR) représente la population canadienne. MÉTHODOLOGIE: Nous avons adopté une approche transversale pour étudier une cohorte prospective d'adultes vivant dans la communauté âgés de 35 à 69 ans et répondant aux critères d'inclusion de l'étude CAHHM, ainsi qu'une cohorte d'adultes âgés de 35 à 69 ans ayant participé au volet de réponse rapide de l'Enquête sur la santé dans les collectivités canadiennes (ESCC) de 2015. Le score de risque INTERHEART individuel des participants a été calculé à partir des moyennes et des proportions rapportées à l'échelle globale et à l'échelle provinciale. RÉSULTATS: Les différences entre les participants du volet CAHHM-HSR et ceux du volet de réponse rapide de l'ESCC de 2015 étaient minimes quant à l'âge (56,3 ans vs 51,7 ans en moyenne), à la proportion d'hommes (44,9 % vs 49,3 %) et au score de risque INTERHEART moyen (9,7 vs 10,1). On a toutefois noté des différences plus importantes en ce qui concerne les caractéristiques suivantes : éducation postsecondaire (86,8 % vs 70,2 %), origine ethnique chinoise (11,0 % vs 3,3 %), obésité (23,2 % vs 29,3 %), tabagisme actuel (6,1 % vs 18,4 %) et absence d'antécédents d'examen cardiaque (30,4 % vs 55,9 %). CONCLUSIONS: Les participants du volet CAHHM-HSR sont plus âgés et ont un statut socioéconomique plus élevé que ceux du volet de réponse rapide de l'ESCC, mais ont un score de risque INTERHEART moyen comparable. Les différences quant aux stratégies d'échantillonnage et des données manquantes pourraient expliquer certains des écarts observés entre la cohorte CAHHM-HSR et celle des adultes canadiens vivant dans la communauté; il conviendrait d'en tenir compte lorsqu'on utilise les données du volet CAHHM-HSR à des fins de recherche scientifique.

13.
J Trace Elem Med Biol ; 62: 126603, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32623095

RESUMEN

Zinc is an essential trace element in humans. Zinc deficiency can result in a range of serious medical conditions which include effects on growth and development, the immune system, the central nervous system, and the gastrointestinal system. Diagnosis of zinc deficiency is often precluded by the lack of a noninvasive and reliable biomarker. Zinc concentration in nail is considered an emerging biomarker of zinc status in humans. Whether zinc in nail accurately reflects zinc status is beyond the scope of the current study, but is an important research question. The development of a portable method to quickly assess zinc concentration from a single nail clipping could be a useful advance. In this study, single toenail clippings from 60 individuals living in Atlantic Canada were measured for zinc using a portable X-ray fluorescence (XRF) technique. These samples were obtained from the Atlantic PATH cohort, part of the largest chronic disease study ever performed in Canada. Each toenail clipping was measured using three 300 s trials with a mono-energetic portable XRF system. Results were then assessed using two different approaches to the XRF analysis: (1) factory-calibrated zinc concentrations were output from each trial, and (2) energy spectra were analyzed for the characteristic X-rays resulting from zinc. Following the measurement of zinc using the non-destructive portable XRF method, the same clippings were measured for zinc concentration using the "gold standard" technique of inductively coupled plasma-mass spectrometry (ICP-MS). A linear equation of best fit was determined for the relationship between average XRF output zinc concentration and ICP-MS zinc concentration, with a correlation coefficient r = 0.60. Similarly, a linear equation of best fit was found for the relationship between a normalized XRF energy spectrum zinc signal and ICP-MS zinc concentration, with a correlation coefficient r = 0.68. Individual ICP-MS zinc concentrations ranged from 32 µg/g to 140 µg/g, with a population average of 85 µg/g. The results of this study indicate that portable XRF is a sensitive method for the measurement of zinc in a single nail clipping, and provides a reasonable estimation of zinc concentration. Further method development is required before portable XRF be considered a routine alternative to ICP-MS for the assessment of zinc in nail clippings.


Asunto(s)
Fluorescencia , Uñas/química , Zinc/química , Humanos , Espectrometría de Masas
14.
Annu Rev Chem Biomol Eng ; 11: 503-521, 2020 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-32155349

RESUMEN

Ammonia is a critically important industrial chemical and is largely responsible for sustaining the growing global population. To provide ammonia to underdeveloped regions and/or regions far from industrial production hubs, modular systems have been targeted and often involve unconventional production methodologies. These novel approaches for ammonia production can tap renewable resources at smaller scales located at the point of use, while decreasing the CO2 footprint. Plasma-assisted catalysis and electrochemical ammonia synthesis have promise owing to their atmospheric pressure and low-temperature operation conditions and the ability to construct units at scales desired for modularization. Fundamental and applied studies are underway to assess these processes, although many unknowns remain. In this review, we discuss recent developments and opportunities for unconventional ammonia synthesis with a focus on plasma-stimulated systems.


Asunto(s)
Amoníaco/síntesis química , Catálisis , Estructuras Metalorgánicas/química , Nitrógeno/química , Gases em Plasma/química , Energía Renovable
15.
Exp Aging Res ; 45(1): 28-40, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30707652

RESUMEN

Background/Study Context. Adaptation to normative age-related declines in memory is an important but understudied aspect of successful aging. The purpose of the present study was to shed new light on memory self-efficacy and beliefs about memory and aging as two integral aspects of adult cognition with relevance to successful aging. METHODS: Young (19 to 27 years) and community-dwelling older adults (60 to 94 years) from the Louisiana Healthy Aging Study (LHAS) completed an adapted Memory Functioning Questionnaire (MFQ) which includes a memory self-efficacy subscale, the Memory Controllability Inventory (MCI), and the Aging Concerns Scale (ACS). RESULTS: Nonagenarians' self-reported memory and beliefs about memory and aging were of central interest. We compared their responses to three younger reference groups to examine hypothesized differences in self-reported memory and beliefs about memory and aging in very late life. Results yielded age effects for most of the MFQ and MCI subscales demonstrating more positive subjective views about memory functioning and control over memory for the young adults. Correlation and regression analyses were conducted to isolate factors that may be associated with memory self-efficacy. Age, symptoms of depression, and memory control beliefs accounted for approximately half of the variance in memory self-efficacy ratings. CONCLUSION: These data indicate that although memory self-efficacy may be age sensitive, we detected no differences in subjective views across the three older groups. Implications for cognitive adaptability and successful aging are considered.


Asunto(s)
Envejecimiento/psicología , Envejecimiento Saludable , Memoria/fisiología , Autoeficacia , Adulto , Anciano , Anciano de 80 o más Años , Cognición , Femenino , Estado de Salud , Humanos , Individualidad , Louisiana , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores Socioeconómicos , Adulto Joven
16.
Mem Cognit ; 47(5): 923-935, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30783910

RESUMEN

Prospective memory (PM) is typically measured using keypresses in laboratory paradigms, which therefore assess only discrete, stage-like processes. In the present study we manipulated focal and nonfocal PM cue conditions, as well as participants' focus on different aspects of the PM/ongoing task set, using the methodology to capture dynamic computer mouse movements. The software captured mouse trajectories during lexical decisions and PM responses. We replicated many findings typical in the PM literature, including the accuracy advantage for focal over nonfocal conditions and longer ongoing-task response times for nonfocal conditions. Participants' movement trajectories during PM responses revealed evidence for both spontaneous-retrieval and strategic-monitoring processes in focal and nonfocal PM retrieval conditions. During trials suggestive of spontaneous retrieval, mouse trajectories initially went toward the typical ongoing-task response but turned mid-trajectory toward the PM response field on the opposite side of the computer screen. In nonfocal conditions, these trajectory reversals had a wider arc and took longer to complete, reflecting the likely greater retrospective retrieval requirements of nonfocal conditions. Regarding what are more likely to be strategic-monitoring processes, a significant portion of responses traveled directly to the PM response field, as though people were prepared to make such a response.


Asunto(s)
Memoria Episódica , Recuerdo Mental/fisiología , Desempeño Psicomotor/fisiología , Adulto , Humanos , Adulto Joven
17.
Q J Exp Psychol (Hove) ; 72(9): 2328-2341, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30808272

RESUMEN

Recognition memory is often viewed as the end-product of discrete cognitive events, involving the combination of latent operations such as the assessment of memory strength, the decision time, and the memory judgement. Recently, researchers have begun using the physical dynamics of memory retrieval to provide insight into the dynamic, possibly non-discrete, processes that underlie memory decisions. In this study, the underlying distributional properties of targets and lures were manipulated by populating lists with items drawn from either homogeneous or heterogeneous word frequency and context variability ranges. In all conditions, participants' x-, y-mouse coordinates were recorded as they processed test items, allowing estimates of response dynamics (e.g., initial deviation and area under the curve [AUC]), and eventual old/new responses. The stimulus manipulations affected the distribution shapes and, to a greater degree, the placements of subjective confidence thresholds. We observed tight correspondences between confidence and AUC for both hits and correct rejections. We interpret these results within dynamic models of recognition memory.


Asunto(s)
Recuerdo Mental/fisiología , Metacognición/fisiología , Desempeño Psicomotor/fisiología , Reconocimiento en Psicología/fisiología , Adulto , Femenino , Humanos , Masculino , Reconocimiento Visual de Modelos/fisiología , Lectura , Adulto Joven
18.
CMAJ ; 190(23): E710-E717, 2018 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-29891475

RESUMEN

BACKGROUND: Understanding the complex interaction of risk factors that increase the likelihood of developing common diseases is challenging. The Canadian Partnership for Tomorrow Project (CPTP) is a prospective cohort study created as a population-health research platform for assessing the effect of genetics, behaviour, family health history and environment (among other factors) on chronic diseases. METHODS: Volunteer participants were recruited from the general Canadian population for a confederation of 5 regional cohorts. Participants were enrolled in the study and core information obtained using 2 approaches: attendance at a study assessment centre for all study measures (questionnaire, venous blood sample and physical measurements) or completion of the core questionnaire (online or paper), with later collection of other study measures where possible. Physical measurements included height, weight, percentage body fat and blood pressure. Participants consented to passive follow-up through linkage with administrative health databases and active follow-up through recontact. All participant data across the 5 regional cohorts were harmonized. RESULTS: A total of 307 017 participants aged 30-74 from 8 provinces were recruited. More than half provided a venous blood sample and/or other biological sample, and 33% completed physical measurements. A total of 709 harmonized variables were created; almost 25% are available for all participants and 60% for at least 220 000 participants. INTERPRETATION: Primary recruitment for the CPTP is complete, and data and biosamples are available to Canadian and international researchers through a data-access process. The CPTP will support research into how modifiable risk factors, genetics and the environment interact to affect the development of cancer and other chronic diseases, ultimately contributing evidence to reduce the global burden of chronic disease.


Asunto(s)
Investigación Biomédica/organización & administración , Enfermedad Crónica/prevención & control , Medicina Preventiva/organización & administración , Adulto , Anciano , Canadá/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desarrollo de Programa , Estudios Prospectivos , Factores de Riesgo , Voluntarios
19.
Front Psychol ; 9: 17, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29434559

RESUMEN

Food image fMRI paradigms are used widely for investigating the neural basis of ingestive behavior. However, these paradigms have not been validated in terms of ingestive behavior constructs, engagement of food-relevant neural systems, or test-retest reliability, making the generalizability of study findings unclear. Therefore, we validated the Macronutrient Picture System (MaPS) (McClernon et al., 2013), which includes food images from the six categories represented in the Geiselman Food Preference Questionnaire (FPQ) (Geiselman et al., 1998). Twenty-five healthy young adults (n = 21 female, mean age = 20.6 ± 1.1 years, mean BMI = 22.1 ± 1.9 kg/m2) rated the MaPS images in terms of visual interest, appetitive quality, nutrition, emotional valence, liking, and frequency of consumption, and completed the FPQ. In a second study, 12 individuals (n=8 female, mean age = 25.0 ± 6.5 years, mean BMI = 28.2 ± 8.7 kg/m2) viewed MaPS and control images (vegetables and non-food) during two separate 3T BOLD fMRI scans after fasting overnight. Intuitively, high fat/high sugar (HF/HS) and high fat/high complex carbohydrate (HF/HCCHO) images achieved higher liking and appetitive ratings, and lower nutrition ratings, than low fat/low complex carbohydrate/high protein (LF/LCHO/HP) images on average. Within each food category, FPQ scores correlated strongly with MaPS image liking ratings (p < 0.001). Brain activation differences between viewing images of HF/HS and vegetables, and between HF/HCCHO and vegetables, were seen in several reward-related brain regions (e.g., putamen, insula, and medial frontal gyrus). Intra-individual, inter-scan agreement in a summary measure of brain activation differences in seven reward network regions of interest was high (ICC = 0.61), and was even higher when two distinct sets of food images with matching visual ratings were shown in the two scans (ICC = 0.74). These results suggest that the MaPS provides valid representation of food categories and reliably activates food-reward-relevant neural systems.

20.
Prev Med ; 105: 326-331, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28987335

RESUMEN

Owing to an aging population and medical advances, the anticipated growth and prevalence of multimorbidity has been recognized as a significant challenge and priority in health care settings. Although physical activity has been shown to play a vital role in the primary and secondary prevention of chronic disease, much less is known about the relationship between physical activity and multimorbidity. The objective of the present study was to examine the relationship between physical activity levels and multimorbidity in male and female adults after adjusting for key demographic, geographical, and lifestyle factors. The study drew data from a prospective cohort in Atlantic Canada (2009-2015). The sample included 18,709 participants between the ages of 35-69. Eighteen chronic diseases were identified. Physical activity levels were estimated based on the long form of the International Physical Activity Questionnaire. Using logistic regression analysis, we found that multimorbid individuals were significantly more likely to be physically inactive (OR=1.26; 95% CI 1.10, 1.44) after adjusting for key sociodemographic and lifestyle characteristics. Additional stratified analyses suggest that the magnitude of the effect between multimorbidity and physical activity was stronger for men (OR=1.41; 95% CI 1.12, 1.79) than women (OR=1.18; CI 1.00, 1.39) and those living in rural (OR=1.43; CI 1.10, 1.85) versus urban (OR=1.20; CI 1.02, 141) areas. Given the generally low levels of physical activity across populations and a growing prevalence of multimorbidity, there is a need for a prospective study to explore causal associations between physical activity, multimorbidity, and health outcomes.


Asunto(s)
Enfermedad Crónica/prevención & control , Ejercicio Físico/fisiología , Estilo de Vida , Multimorbilidad/tendencias , Adulto , Anciano , Canadá , Femenino , Geografía , Conductas Relacionadas con la Salud , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad
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