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We investigate the turbulence statistics in a multiphase plume made of heavy particles (particle Reynolds number at terminal velocity is 450). Using refractive-index-matched stereoscopic particle image velocimetry, we measure the locations of particles whose buoyancy drives the formation of a multiphase plume, together with the local velocity of the induced flow in the ambient salt–water. Measurements of the mean axial flow in the plume centreplane follow Gaussian profiles and that of the mean radial flow is consistent with integral plume theory. The turbulence characteristics resemble those measured in a bubble plume, including strong anisotropy in the normal Reynolds stresses. However, we observe structural differences between the two multiphase plumes. First, the skewness of the probability density function of the axial velocity fluctuations is not that which would be predicted by simply reversing the direction of a bubble plume. Second, in contrast to a bubble plume, the particle plume has a non-negligible fluid-shear production term in the turbulent kinetic energy (TKE) budget. Third, the radial decay of all measured terms in the TKE budget is slower than those in a bubble plume. Despite these dissimilarities, a bigger picture emerges that applies to both flows. The TKE production by particles (or bubbles) roughly balances the viscous dissipation, except near the plume centreline. The one-dimensional power spectra of the velocity fluctuations show a
power law that puts both the particle and bubble plume in a category different from single-phase shear-flow turbulence.
Cognitive impairment associated with lifetime major depressive disorder (MDD) is well-supported by meta-analytic studies, but population-based estimates remain scarce. Previous UK Biobank studies have only shown limited evidence of cognitive differences related to probable MDD. Using updated cognitive and clinical assessments in UK Biobank, this study investigated population-level differences in cognitive functioning associated with lifetime MDD.
Associations between lifetime MDD and cognition (performance on six tasks and general cognitive functioning [g-factor]) were investigated in UK Biobank (N-range 7,457–14,836, age 45–81 years, 52% female), adjusting for demographics, education, and lifestyle. Lifetime MDD classifications were based on the Composite International Diagnostic Interview. Within the lifetime MDD group, we additionally investigated relationships between cognition and (a) recurrence, (b) current symptoms, (c) severity of psychosocial impairment (while symptomatic), and (d) concurrent psychotropic medication use.
Lifetime MDD was robustly associated with a lower g-factor (β = −0.10, PFDR = 4.7 × 10−5), with impairments in attention, processing speed, and executive functioning (β ≥ 0.06). Clinical characteristics revealed differential profiles of cognitive impairment among case individuals; those who reported severe psychosocial impairment and use of psychotropic medication performed worse on cognitive tests. Severe psychosocial impairment and reasoning showed the strongest association (β = −0.18, PFDR = 7.5 × 10−5).
Findings describe small but robust associations between lifetime MDD and lower cognitive performance within a population-based sample. Overall effects were of modest effect size, suggesting limited clinical relevance. However, deficits within specific cognitive domains were more pronounced in relation to clinical characteristics, particularly severe psychosocial impairment.
Studies suggest that alcohol consumption and alcohol use disorders have distinct genetic backgrounds.
We examined whether polygenic risk scores (PRS) for consumption and problem subscales of the Alcohol Use Disorders Identification Test (AUDIT-C, AUDIT-P) in the UK Biobank (UKB; N = 121 630) correlate with alcohol outcomes in four independent samples: an ascertained cohort, the Collaborative Study on the Genetics of Alcoholism (COGA; N = 6850), and population-based cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC; N = 5911), Generation Scotland (GS; N = 17 461), and an independent subset of UKB (N = 245 947). Regression models and survival analyses tested whether the PRS were associated with the alcohol-related outcomes.
In COGA, AUDIT-P PRS was associated with alcohol dependence, AUD symptom count, maximum drinks (R2 = 0.47–0.68%, p = 2.0 × 10−8–1.0 × 10−10), and increased likelihood of onset of alcohol dependence (hazard ratio = 1.15, p = 4.7 × 10−8); AUDIT-C PRS was not an independent predictor of any phenotype. In ALSPAC, the AUDIT-C PRS was associated with alcohol dependence (R2 = 0.96%, p = 4.8 × 10−6). In GS, AUDIT-C PRS was a better predictor of weekly alcohol use (R2 = 0.27%, p = 5.5 × 10−11), while AUDIT-P PRS was more associated with problem drinking (R2 = 0.40%, p = 9.0 × 10−7). Lastly, AUDIT-P PRS was associated with ICD-based alcohol-related disorders in the UKB subset (R2 = 0.18%, p < 2.0 × 10−16).
AUDIT-P PRS was associated with a range of alcohol-related phenotypes across population-based and ascertained cohorts, while AUDIT-C PRS showed less utility in the ascertained cohort. We show that AUDIT-P is genetically correlated with both use and misuse and demonstrate the influence of ascertainment schemes on PRS analyses.
Research on producer willingness to adopt individual best pasture management practices (BMPs) is extensive, but less attention has been paid to producers simultaneously adopting multiple, complementary BMPs. Applications linking primary survey data on BMP adoption to water quality biophysical models are also limited. A choice-experiment survey of livestock producers is analyzed to determine willingness to adopt pasture BMPs. Sediment abatement curves are derived by linking estimates of producer responsiveness to incentives to adopt rotational grazing with a biophysical simulation model. Current cost share rates of $24/acre should yield a 12% decrease in sediment loading from pastures.
OBJECTIVES/SPECIFIC AIMS: Selective loss of long-projecting neural circuitry is a common feature of many neurodegenerative diseases, such as the vulnerable nigrostriatal pathway in Parkinson’s disease (PD). Current in vitro approaches for studying disease development generally do not mimic complex anatomical features of the afflicted substrates such as long axonal pathways between stereotypical neural populations. Such exquisite features are not only crucial for neural systems function but may also contribute to the preferential vulnerability and pathophysiological progression of these structures in neurodegenerative disease. We have previously developed micro-tissue engineered neural networks to recapitulate the anatomy of long-projecting cortical axonal tracts encased in a tubular hydrogel.1 Recently, we have extended this work to include the first tissue-engineered nigrostriatal pathway that was anatomically-inspired to replicate the structure and function of the native pathway.2 Notably, this tissue-engineered brain pathway possesses three-dimensional (3D) structure, multicellular composition, and architecture of long axonal tracts between distinct neuronal populations. Therefore, in the current study we apply this system as a biofidelic test-bed for evaluating axonal pathway development, maturation, and pathophysiology. METHODS/STUDY POPULATION: Dopaminergic neurons from the ventral mesencephalon and medium spiny neurons (MSNs) from the striatum were separately isolated from rat embryos. Tissue-engineered nigrostriatal pathways were formed by initially seeding dopaminergic neuron aggregates at one end of hollow hydrogel micro-columns with a central extracellular matrix, collectively spanning up to several centimeters in length. Several days later, tissue-engineered MSN aggregate was seeded on the other end and was allowed to integrate. Immunocytochemistry (ICC) and confocal microscopy were used to assess health, cytoarchitecture, synaptic integration, and mitochondrial dynamics with stains that label cell nuclei (Hoechst) and mitochondria (MitoTracker Red) and antibodies that recognize axons (anti-β-tubulinIII), neurons/dendrites (anti-MAP2), dopaminergic neurons/axons (anti-tyrosine hydroxylase; TH), and MSNs (anti-DARPP-32). RESULTS/ANTICIPATED RESULTS: Seeding tubular micro-columns with dopaminergic neuronal aggregates resulted in unidirectional axonal extension, ultimately spanning >5mm by 14 days in vitro. For constructs also seeded with Tissue-engineered, ICC confirmed the presence of the appropriate neuronal sub-types in the two aggregate populations, specifically TH+ dopaminergic neurons and DARPP-32+ MSNs. Moreover, confocal microscopy revealed extensive axonal-dendritic integration and synapse formation involving the dopaminergic axons and MSN somata/dendrites. Collectively, these constructs mimicked the general cytoarchitecture of the in vivo nigrostriatal pathway: a discrete population of dopaminergic neurons with long-projecting 3D axonal tracts that were synaptically integrated with a population of MSNs. Mitochondria structure along axonal tracts was also observed using MitoTracker staining, revealing dynamic intra-axonal mitochondrial motility in this system. Ongoing studies are evaluating real-time mitochondrial dynamics and axonal physiology in this tissue-engineered nigrostriatal pathway in vitro, under both baseline conditions as well as following the addition of exogenous α-Synuclein fibrils to model synucleinopathy in PD. DISCUSSION/SIGNIFICANCE OF IMPACT: This tissue-engineered nigrostriatal pathway provides an anatomically-inspired platform with neuronal-axonal architecture that structurally and functionally emulates the nigrostriatal pathway in vivo. We are applying this paradigm as a powerful in vitro test-bed for understanding mitochondrial activity and inter-axonal energetics pathways under homeostatic as well as PD pathological conditions. Successful demonstration will serve as proof-of-concept that this technique can be used to study mitochondria pathology in personalized constructs built using cells derived from PD patients in order to evaluate pharmacological therapies targeted at improving mitochondrial resiliency and fitness so as to delay and/or prevent dopaminergic axonal/neuronal degeneration in tailored to specific PD patients.
The Erasmus Plus programme ‘Innovative Education and Training in high power laser plasmas’, otherwise known as PowerLaPs, is described. The PowerLaPs programme employs an innovative paradigm in that it is a multi-centre programme where teaching takes place in five separate institutes with a range of different aims and styles of delivery. The ‘in class’ time is limited to four weeks a year, and the programme spans two years. PowerLaPs aims to train students from across Europe in theoretical, applied and laboratory skills relevant to the pursuit of research in laser–plasma interaction physics and inertial confinement fusion (ICF). Lectures are intermingled with laboratory sessions and continuous assessment activities. The programme, which is led by workers from the Technological Educational Institute (TEI) of Crete, and supported by co-workers from the Queen’s University Belfast, the University of Bordeaux, the Czech Technical University in Prague, Ecole Polytechnique, the University of Ioannina, the University of Salamanca and the University of York, has just completed its first year. Thus far three Learning Teaching Training (LTT) activities have been held, at the Queen’s University Belfast, the University of Bordeaux and the Centre for Plasma Physics and Lasers (CPPL) of TEI Crete. The last of these was a two-week long Intensive Programme (IP), while the activities at the other two universities were each five days in length. Thus far work has concentrated upon training in both theoretical and experimental work in plasma physics, high power laser–matter interactions and high energy density physics. The nature of the programme will be described in detail and some metrics relating to the activities carried out to date will be presented.
Relatively few older adults are physically active despite extensive research exploring barriers and facilitators and concomitant interventions designed to enhance participation rates. Building on the growing literature that considers the subjective experience of being physically active, we explored the meanings that older Canadian men attributed to physical activity broadly defined. Thus, we examined their experiences and perceptions of exercise, sport and/or leisure-time physical activities. Data are presented from qualitative interviews with 22 community-dwelling Canadian men aged 67–90. Our analysis resulted in three overarching categories that subsumed the men's understanding of physical activity. ‘I do it for my health’ described how the men stated that their primary reason for engaging in exercise was to maintain their health and body functionality so that they could age well and continue to participate in sport and leisure. ‘It feels good’ referred to the various ways that the men derived pleasure from being active, including the physical sensations, psychological benefits and social connections they derived from their participation. ‘It gets tougher’ detailed the ways that the men were finding physical activity to be increasingly difficult as a result of the onset of health problems, declining body functionality and the social realities of ageing. We discuss our findings in light of the extant literature concerning age relations, ageism, and the third and fourth ages.
Each year our Clinical and Translational Science Award pilot projects program awards approximately $500,000 in translational pilot funding to advance health in South Texas. We identified needs to improve the timeliness, transparency, and efficiency of the review process by surveying applicants. Lean six sigma methodologies, following a “Define, Measure, Analyze, Improve, Control” approach, were used to streamline the pilot project application and review by identifying and removing bottlenecks from process flows. We evaluated the impact of our reorganized review process by surveying applicants and reviewers. Process mapping identified pilot project review as the main source of delay, leading to the implementation of a study section-style review mechanism. After one cycle, 90.3% of pilot applicants and 100% of reviewers were highly satisfied with the new processes and time to award notice was reduced by 2 months. All reviewers familiar with both review processes preferred the study section. We demonstrated how lean six sigma, a methodology not commonly applied in research administration, can be used to evaluate processes in translational science in academic health centers. Through our efforts, we were able to improve timeliness, transparency, and efficiency of the review process.
Similar to their younger counterparts, older adults (age 60+) are increasingly turning to online dating sites to find potential romantic and sexual partners. In this paper, we draw upon qualitative data from a thematic analysis of 320 randomly selected online dating profiles posted by Canadian heterosexual older adults who self-identified as Asian, Black, Caucasian or Native American. In particular, we examined how the older adults’ self-presentations varied according to race/ethnicity, age and gender, and how the language they used to describe themselves and their preferred potential partners reflected and reinforced idealised images of ageing. Our analysis identified five primary ways in which the older adults portrayed themselves. They depicted themselves as active and busy with cultural/artistic, social and adventurous activities; and also as physically healthy and intellectually engaged. Third, they emphasised the ways in which they were productive through work and volunteer activities. Fourth, they accentuated their positive approach to life, identifying themselves as happy, fun-loving and humorous individuals. Finally, they highlighted their personable characteristics, portraying themselves as trustworthy and caring. We discuss our findings with a particular focus on gender differences, drawing on literature on masculinity and femininity, and also look at capital and power relations by considering the online dating setting as a field in the Bourdieusian sense.
This study examined how relevant Rowe and Kahn’s three criteria of successful aging were to older adults’ self-portrayals in online dating profiles: low probability of disease and disability, high functioning, and active life engagement. In this cross-sectional study, 320 online dating profiles of older adults were randomly selected and coded based on the criteria. Logistic regression analyses determined whether age, gender, and race/ethnicity predicted self-presentation. Few profiles were indicative of successful aging due to the low prevalence of the first two criteria; the third criterion, however, was identified in many profiles. Native Americans were significantly less likely than other ethnic groups to highlight the first two criteria. Younger age predicted presenting the first criterion. Women’s presentation of the third criterion remained significantly high with age. The findings suggest that the criteria may be unimportant to older adults when seeking partners, or they may reflect the exclusivity of this construct.
A systematic review was conducted in order to explore the effectiveness of communication-skills training interventions in end-of-life care with noncancer acute-based healthcare staff.
Articles were included if they (1) focused on communication-skills training in end-of-life/palliative care for noncancer acute-based staff and (2) reported an outcome related to behavior change with regard to communication. Sixteen online databases were searched, which resulted in 4,038 potential articles. Screening of titles left 393 articles that met the inclusion criteria. Abstracts (n = 346) and full-text articles (n = 47) were reviewed, leaving 10 papers that met the criteria for our review. All articles explored the effect of communication-skills training on aspects of staff behavior; one study measured the effect on self-efficacy, another explored the impact on knowledge and competence, and another measured comfort levels in discussing the end of life with patients/families. Seven studies measured a number of outcomes, including confidence, attitude, preparedness, stress, and communication skills.
Few studies have focused on end-of-life communication-skills training in noncancer acute-based services. Those that do have report positive effects on staff behavior with regard to communication about the end of life with patients and families. The studies varied in terms of the population studied and the health services involved, and they scored only moderately or weakly on quality. It is a challenge to draw a definite conclusion about the effectiveness of training interventions in end-of-life communication because of this. However, the findings from our review demonstrate the potential effectiveness of a range of training interventions with healthcare professionals on confidence, attitude, self-efficacy, and communication skills.
Significance of results:
Further research is needed to fully explore the effectiveness of existing training interventions in this population, and evidence using objective measures is particularly needed. Ideally, randomized controlled trials or studies using control groups and longer follow-ups are needed to test the effectiveness of interventions.
Despite burgeoning evidence linking early exposure to child maltreatment (CM) to deficits in self-regulation, the pathways to strong regulatory development in these children are not well understood, and significant heterogeneity is observed in their outcomes. Experiences of autonomy may play a key role in transmitting self-regulatory capacity across generations and help explain individual differences in maltreatment outcomes. In this study, we investigated multigenerational associations between Generation 1 (G1)–Generation 2 (G2) mothers' early experience of warmth and autonomy in relation to their own mothers and their Generation 3 (G3) children's autonomic physiological regulation in CM (n = 85) and non-CM (n = 128) families. We found that G2 mothers who recalled greater autonomy in their childhood relationship with their G1 mothers had preschool-age G3 children with higher respiratory sinus arrhythmia at baseline when alone while engaged in individual challenge tasks, during social exchanges with their mother in joint challenge tasks, and during the portions of the strange situation procedure when the mother was present. Although no clear mediators of this association emerged, multigenerational links among G1–G2 relations, maternal representations of her child, child behavior, and child respiratory sinus arrhythmia differed by maltreatment status, thus possibly representing important targets for future research and intervention.
This paper examines how older men perceive, experience and internalise ageist prejudice in the context of their everyday lives. We draw on in-depth interviews with 29 community-dwelling Canadian men aged 65–89. Although one-third of our participants were unfamiliar with the term ageism, the majority felt that age-based discrimination was prevalent in Canadian society. Indicating that they themselves had not been personally subjected to ageism, the men considered age-based discrimination to be a socially distant problem. The men explained their perceived immunity to ageism in terms of their youthful attitudes and active lifestyles. The men identified three groups who they considered to be particularly vulnerable to age-based discrimination, namely women, older workers and frail elders residing in institutions. At the same time, the majority of our participants had internalised a variety of ageist and sexist stereotypes. Indeed, the men assumed that later life was inevitably a time of physical decline and dependence, and accepted as fact that older adults were grumpy, poor drivers, unable to learn new technologies and, in the case of older women, sexually unattractive. In this way, a tension existed between the men's assertion that ageism did not affect their lives and their own internalisation of ageist stereotypes. We consider our findings in relation to the theorising about ageism and hegemonic masculinity.
In this article, we draw upon interviews with 14 men and 15 women aged 51–92 to examine the embodied experiences of Canadian power mobility device users. In particular, we investigate how individuals ageing with mobility impairments perceived and experienced the practical impacts and symbolic cultural connotations of utilising a power mobility device. Our findings reveal that those participants who had begun to use their power mobility devices later in life were dismayed by and apprehensive about the significance of their diminishing physical abilities in the context of the societal privileging of youthful and able bodies. At the same time, the participants who had used a power mobility device from a young age were fearful of prospective bodily declines, and discussed the significance and consequences of being unable to continue to operate their power mobility devices autonomously in the future. We consider the ways in which the participants attempted to manage, mitigate and reframe their experiences of utilising power mobility devices in discriminatory environments. We discuss our findings in relation to on-going theoretical debates pertaining to the concepts of ‘biographical disruption’ and the third and fourth ages.
People who have read War and Peace more than once, and enjoyed it immensely, can often scarcely remember a thing about it.
The concept of redundancy employed in this essay is the one used in mathematics and linguistics to designate symbols that do not add information to a sequence. One of the hazards of teaching twentieth-century war literature is the tacit inference of redundancy by readers, namely that the representational conventions as well as the facts and values represented are ‘predictable from … context’. The claim that twentieth-century war writing is made superfluous by War and Peace (1869) is polemical, but it is also intended to do serious work: to draw attention to representations of war which are not predictable from context, and to renew questions such as why representing war as irrational, murderous activity is unefficacious, and why we would imagine otherwise.
The designs of War and Peace as war writing can be recognised as early as 1853, when Tolstoy published a story drawing on his own military experience in the Caucasus:
War always interested me: not war in the sense of manoeuvres devised by great generals – my imagination refused to follow such immense movements, I did not understand them – but the reality of war, the actual killing. I was more interested to know in what way and under the influence of what feeling one soldier kills another than to know how the armies were arranged at Austerlitz and Borodino.