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Would increasing access to recreational places promote healthier weights and a healthier nation?
No full textAddressing gaps in evidence on causal associations, this study tested the hypothesis that better access to recreational places close to home helps people to maintain lower body mass index (BMI) using a retrospective longitudinal study design and up to 6 years of data for the same individuals (1,522,803 men and 183,618 women). Participants were military veterans aged 20–64 who received healthcare through the U.S. Department of Veterans Affairs in 2009–2014 and lived in a metropolitan area. Although there were cross-sectional associations, we found no longitudinal evidence that access to parks and fitness facilities was associated with BMI for either men or women in the full sample or in subgroups of residential movers and stayers. Our findings suggest that simply increasing the number of parks and fitness facilities may not be enough to achieve needed population-level reductions in weight
Automated Study Challenges the Existence of a Foundational Statistical-Learning Ability in Newborn Chicks
No full textWhat mechanisms underlie learning in newborn brains? Recently, researchers reported that newborn chicks use unsupervised statistical learning to encode the transitional probabilities (TPs) of shapes in a sequence, suggesting that TP-based statistical learning can be present in newborn brains. Using a preregistered design, we attempted to reproduce this finding with an automated method that eliminated experimenter bias and allowed more than 250 times more data to be collected per chick. With precise measurements of each chick’s behavior, we were able to perform individual-level analyses and substantially reduce measurement error for the group-level analyses. We found no evidence that newborn chicks encode the TPs between sequentially presented shapes. None of the chicks showed evidence for this ability. Conversely, we obtained strong evidence that newborn chicks encode the shapes of individual objects, showing that this automated method can produce robust results. These findings challenge the claim that TP-based statistical learning is present in newborn brains
Intake of Vegetables and Fruits Through Young Adulthood Is Associated with Better Cognitive Function in Midlife in the US General Population
No full textBackground: Vegetables and fruits (VF) may differentially affect cognitive functions, presumably due to their various nutrient contents, but evidence from epidemiologic studies is limited. Objectives The aim of this study was to examine the long-term association between VF intakes, including VF subgroups, in young adulthood and cognitive function in midlife. Methods: A biracial cohort of 3231 men and women aged 18–30 y at baseline in 1985–1986 were followed up for 25 y in the Coronary Artery Risk Development in Young Adults Study. Diet was measured at baseline, and in examination years 7 and 20. Cognitive function was assessed at examination year 25 through the use of 3 tests: the Rey Auditory Verbal Learning Test (RAVLT), the Digit Symbol Substitution Test (DSST), and the Stroop test. The mean differences (MDs) with 95% CIs in cognitive scores across intake categories were estimated through the use of the multivariable-adjusted general linear regression model. Results: Excluding potatoes, intake of whole vegetables was significantly associated with a better cognitive performance after adjustment for potential confounders in all 3 cognitive tests (quintile 5 compared with quintile 1—RAVLT, MD: 0.33; 95% CI: 0.01, 0.64; -trend = 0.08; DSST, MD: 2.84; 95% CI: 0.93, 4.75; -trend < 0.01; Stroop test, MD: −2.87; 95% CI: −4.24, −1.50; -trend < 0.01]. Similarly, intake of fruits, except fruit juices, was significantly related to a better cognitive performance (quintile 5 compared with quintile 1—DSST, MD: 2.41; 95% CI: 0.70, 4.12; trend = 0.03). Conclusions: This study supports the long-term benefits of VF consumption on cognitive performance, except those VF with relatively low fiber content such as potatoes and fruit juices, among the middle-aged US general population
Long reads reveal the diversification and dynamics of CRISPR reservoir in microbiomes
No full textBackground: Sequencing of microbiomes has accelerated the characterization of the diversity of CRISPR-Cas immune systems. However, the utilization of next generation short read sequences for the characterization of CRISPR-Cas dynamics remains limited due to the repetitive nature of CRISPR arrays. CRISPR arrays are comprised of short spacer segments (derived from invaders’ genomes) interspaced between flanking repeat sequences. The repetitive structure of CRISPR arrays poses a computational challenge for the accurate assembly of CRISPR arrays from short reads. In this paper we evaluate the use of long read sequences for the analysis of CRISPR-Cas system dynamics in microbiomes. Results: We analyzed a dataset of Illumina’s TruSeq Synthetic Long-Reads (SLR) derived from a gut microbiome. We showed that long reads captured CRISPR spacers at a high degree of redundancy, which highlights the spacer conservation of spacer sharing CRISPR variants, enabling the study of CRISPR array dynamics in ways difficult to achieve though short read sequences. We introduce compressed spacer graphs, a visual abstraction of spacer sharing CRISPR arrays, to provide a simplified view of complex organizational structures present within CRISPR array dynamics. Utilizing compressed spacer graphs, several key defining characteristics of CRISPR-Cas system dynamics were observed including spacer acquisition and loss events, conservation of the trailer end spacers, and CRISPR arrays’ directionality (transcription orientation). Other result highlights include the observation of intense array contraction and expansion events, and reconstruction of a full-length genome for a potential invader (Faecalibacterium phage) based on identified spacers. Conclusion: We demonstrate in an in silico system that long reads provide the necessary context for characterizing the organization of CRISPR arrays in a microbiome, and reveal dynamic and evolutionary features of CRISPR-Cas systems in a microbial population
PQS Signaling for More than a Quorum: the Collective Stress Response Protects Healthy Pseudomonas aeruginosa Populations
No full textIn this issue, Bru et al. connect Pseudomonas aeruginosa PQS signaling secretion during stress response to swarming behavior (J.-L. Bru, B. Rawson, C. Trinh, K. Whiteson, et al., J Bacteriol 201:e00383-19, 2019, https://doi.org/10.1128/JB.00383-19). Phage-infected or antibiotic-treated bacterial cells secrete PQS to repel healthy, unexposed cells away from the source of the stress. Thus, the collective stress response mechanism driven by PQS signaling influences spatial organization and population dynamics in P. aeruginosa that may provide competitive advantages in certain niches
The master quorum-sensing regulators LuxR/HapR directly interact with the alpha subunit of RNA polymerase to drive transcription activation in Vibrio harveyi and Vibrio cholerae
No full textIn Vibrio species, quorum sensing controls gene expression for numerous group behaviors, including bioluminescence production, biofilm formation, virulence factor secretion systems, and competence. The LuxR/HapR master quorum sensing regulators activate expression of hundreds of genes in response to changes in population densities. The mechanism of transcription activation by these TetR-type transcription factors is unknown, though LuxR DNA binding sites that lie in close proximity to the −35 region of the promoter are required for activation at some promoters. Here, we show that Vibrio harveyi LuxR directly interacts with RNA polymerase to activate transcription of the luxCDABE bioluminescence genes. LuxR interacts with RNA polymerase in vitro and in vivo and specifically interacts with both the N- and C-terminal domains of the RNA polymerase α-subunit. Amino acid substitutions in the RNAP interaction domain on LuxR decrease interactions between LuxR and the -subunit and result in defects in transcription activation of quorum sensing genes in vivo. The RNAP-LuxR interaction domain is conserved in Vibrio cholerae HapR and is required for activation of the HapR-regulated gene hapA. Our findings support a model in which LuxR/HapR bind proximally to RNA polymerase to drive transcription initiation at a subset of quorum sensing genes in Vibrio species
Deep Underground Neutrino Experiment (DUNE), Far Detector Technical Design Report, Volume IV: Far Detector Single-phase Technology
No full textThe preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay -- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. DUNE is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. Central to achieving DUNE's physics program is a far detector that combines the many tens-of-kiloton fiducial mass necessary for rare event searches with sub-centimeter spatial resolution in its ability to image those events, allowing identification of the physics signatures among the numerous backgrounds. In the single-phase liquid argon time-projection chamber (LArTPC) technology, ionization charges drift horizontally in the liquid argon under the influence of an electric field towards a vertical anode, where they are read out with fine granularity. A photon detection system supplements the TPC, directly enhancing physics capabilities for all three DUNE physics drivers and opening up prospects for further physics explorations. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. Volume IV presents an overview of the basic operating principles of a single-phase LArTPC, followed by a description of the DUNE implementation. Each of the subsystems is described in detail, connecting the high-level design requirements and decisions to the overriding physics goals of DUNE
Gadamer's Distance and Ricoeur's Belonging
Get PDFIt is a commonplace that Gadamer’s hermeneutics and Ricoeur’s hermeneutics emphasize, by way of contrast, a hermeneutics of belonging and a hermeneutics of difference.1 A corollary to this contrasting emphasis is the attribution of a conservative profile to Gadamer’s philosophy and its critical correction in Ricoeur.2 In this paper I want to explore how, in a fundamental way, the situation is in fact the reverse. I will defend my claim by looking at Gadamer’s and Ricoeur’s explications of the hermeneutic structure of human time, which Gadamer construes as an eventful interruption that calls for transformation, and Ricoeur as a three-fold present that binds the finite to the infinite. The juxtaposition of the present as change (against what has been), and the threefold as the extracting of “a figure from a succession” (narrative identity), illustrates—in the logics of the two theories—a distinctive commitment to transformation (Gadamer) and a distinctive commitment to belonging (Ricoeur)
Civic Wealth Creation: A New View of Stakeholder Engagement and Societal Impact
Get PDFPositive societal change happens when community members, supporters, and entrepreneurially minded agents come together to aggregate resources and build new capacities. To explain and inform how societal impact happens across categories of stakeholders, we set forth an integrative framework of civic wealth creation to account for the social, economic, and communal endowments generated by local communities. Our framework shifts the conversation to a “civic” level of analysis that captures the variety of local settings where many societal change initiatives take place—in neighborhoods, villages, and communities where the people who are being helped are intimately involved in creating and implementing the solutions. Civic wealth extends beyond the material resources and physical assets of a community to include intangibles such as health, happiness, and social justice. We draw attention to the importance of citizen engagement and entrepreneurial commerce in the discourse surrounding contemporary societal change efforts. The civic wealth creation framework offers scholars and practitioners across disciplines a new lens through which to view societal impact
Reconceptualizing Necessity Entrepreneurship: A Contextualized Framework of Entrepreneurial Processes Under The Condition of Basic Needs
Get PDFScholarly interest in necessity entrepreneurship has risen steadily over the last four decades, with much of the research in this area focused on distinguishing individuals who are pushed into entrepreneurship by negative factors such as unemployment, from those who are pulled into it by its attractiveness. Yet, although past research has extended knowledge considerably, the dichotomous framing commonly employed in studies in this realm has limited theoretical development, as it ignores important variation among necessity entrepreneurs and, hence, the processes by which they engage in entrepreneurship. In this paper, we seek to reconceptualize the necessity entrepreneurship construct by drawing on a motivational theory of necessity to predict how variation in founders’ basic needs influences the entrepreneurial process, conditional on the level of their human capital endowments, the environmental context in which they are embedded, and the presence of supportive institutional levers. We conclude by discussing the implications of our study and the potential ways in which our theory can be tested and extended