1,669 research outputs found

    Probing Cosmology with Weak Lensing Minkowski Functionals

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    In this paper, we show that Minkowski Functionals (MFs) of weak gravitational lensing (WL) convergence maps contain significant non-Gaussian, cosmology-dependent information. To do this, we use a large suite of cosmological ray-tracing N-body simulations to create mock WL convergence maps, and study the cosmological information content of MFs derived from these maps. Our suite consists of 80 independent 512^3 N-body runs, covering seven different cosmologies, varying three cosmological parameters Omega_m, w, and sigma_8 one at a time, around a fiducial LambdaCDM model. In each cosmology, we use ray-tracing to create a thousand pseudo-independent 12 deg^2 convergence maps, and use these in a Monte Carlo procedure to estimate the joint confidence contours on the above three parameters. We include redshift tomography at three different source redshifts z_s=1, 1.5, 2, explore five different smoothing scales theta_G=1, 2, 3, 5, 10 arcmin, and explicitly compare and combine the MFs with the WL power spectrum. We find that the MFs capture a substantial amount of information from non-Gaussian features of convergence maps, i.e. beyond the power spectrum. The MFs are particularly well suited to break degeneracies and to constrain the dark energy equation of state parameter w (by a factor of ~ three better than from the power spectrum alone). The non-Gaussian information derives partly from the one-point function of the convergence (through V_0, the "area" MF), and partly through non-linear spatial information (through combining different smoothing scales for V_0, and through V_1 and V_2, the boundary length and genus MFs, respectively). In contrast to the power spectrum, the best constraints from the MFs are obtained only when multiple smoothing scales are combined.Comment: 19 pages, 9 figures, 5 table

    The Effects of Sports Simulation on Motor Competency: Bandura’s Social Cognitive Theory

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    The constant growth of video games allows concept innovations such as sports simulation, incorporating realism into video games. In line with this, a study suggests that digital sports can be a tool to improve motor skills, to which Bandura\u27s Social Cognitive of Observational Learning (BCST) became the key concept in both. Therefore, the researchers focused on studying the effects of sports simulation in enhancing motor competencies through BCST. In attaining this, the researchers aim to discover the effects of NBA2k22 on the fundamental basketball skills of novice players and identify how Bandura\u27s Theory contributes to the motor learning and competency of an individual through sports simulation games. For the study, the researchers utilized a sequential explanatory design—a quasi-experimental and simple case study design for the quantitative and qualitative portion of the study, respectively. Three individuals were gathered to perform three tests. Namely, the accuracy pass test, speed dribble test, and bounce pass test for both the pre-test and post-test to assess their skill levels for each movement. The subjects underwent a 2-week intervention wherein each individual played two hours of NBA2k22 MyCareer. Afterward, the subjects were put in a semi-structured interview, further assessing their improvement. The findings of the study support the hypothesis that sports simulation video games have an effect on the dribbling and passing skills of novice basketball players

    Abdominal aortic calcification, bone mineral density and fractures: a systematic review and meta-analysis protocol

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    INTRODUCTION: Abdominal aortic calcification (AAC) is associated with low bone mass and increased fracture risk. Two previous meta-analyses have investigated the association between AAC and fracture. However, these meta-analyses only identified articles until December 2016, undertook limited searches and did not explore potential sources of between-study heterogeneity. We aim to undertake a sensitive and comprehensive assessment of the relationship between AAC, bone mineral density (BMD) as well as prevalent and incident fractures. METHODS: We will search MEDLINE, EMBASE, Web of Science core collection and Google Scholar (top 200 articles sorted by relevance) from their inception to 1 June 2018. Reference lists of included studies and previous systematic reviews will be hand searched for additional eligible studies. Retrospective and prospective cohort studies (cross-sectional, case-control and longitudinal) reporting the association between AAC, BMD and fracture at any site will be included. At least two investigators will independently: (A) evaluate study eligibility and extract data, with a third investigator to adjudicate when discrepancies occur, (B) assess study quality by the Newcastle-Ottawa Scale for each cohort/study. The meta-analysis will be reported in adherence to the Meta-analysis of Observational Studies in Epidemiology criteria. AAC will be grouped as either: (1) AAC present or absent, (2) AAC categorised as \u27low\u27 (referent-lowest reported group) versus \u27high\u27 (all other groups) or (3) dose-response when AAC was assessed in ≥3 groups. Where primary event data were reported in individual studies, pooled risk differences and risk ratios with 95% CI will be calculated, from which, a summary estimate will be determined using DerSimonian-Laird random effects models. For the AAC and BMD pooled analyses, estimates will be expressed as standardised mean difference with 95% CI. We will examine the likelihood of publication bias and where possible, investigate potential reasons for between-study heterogeneity using subgroup analyses and meta-regression. ETHICS AND DISSEMINATION: The study will be submitted to a peer- reviewed journal and disseminated via research presentations. PROSPERO REGISTRATION NUMBER: CRD42018088019

    Distinct hippocampal engrams control extinction and relapse of fear memory

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    Learned fear often relapses after extinction, suggesting that extinction training generates a new memory that coexists with the original fear memory; however, the mechanisms governing the expression of competing fear and extinction memories remain unclear. We used activity-dependent neural tagging to investigate representations of fear and extinction memories in the dentate gyrus. We demonstrate that extinction training suppresses reactivation of contextual fear engram cells while activating a second ensemble, a putative extinction engram. Optogenetic inhibition of neurons that were active during extinction training increased fear after extinction training, whereas silencing neurons that were active during fear training reduced spontaneous recovery of fear. Optogenetic stimulation of fear acquisition neurons increased fear, while stimulation of extinction neurons suppressed fear and prevented spontaneous recovery. Our results indicate that the hippocampus generates a fear extinction representation and that interactions between hippocampal fear and extinction representations govern the suppression and relapse of fear after extinction.We thank J. Dunsmoor for comments on the manuscript. A.F.L. was supported by NIH F31 MH111243 and NIH T32 MH106454. S.L.S. was supported by PD/BD/128076/2016 from the Portuguese Foundation for Science and Technology. Research supported by NIH DP5 OD017908 and New York Stem Cell Science (NYSTEM) C-029157 to C.A.D., NIH R01 MH102595 and NIH R21 EY026446 to M.R.

    Paraoxonase 2 protein is spatially expressed in the human placenta and selectively reduced in labour

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    Humans parturition involves interaction of hormonal, neurological, mechanical stretch and inflammatory pathways and the placenta plays a crucial role. The paraoxonases (PONs 1–3) protect against oxidative damage and lipid peroxidation, modulation of endoplasmic reticulum stress and regulation of apoptosis. Nothing is known about the role of PON2 in the placenta and labour. Since PON2 plays a role in oxidative stress and inflammation, both features of labour, we hypothesised that placental PON2 expression would alter during labour. PON2 was examined in placentas obtained from women who delivered by cesarean section and were not in labour and compared to the equivalent zone of placentas obtained from women who delivered vaginally following an uncomplicated labour. Samples were obtained from 12 sites within each placenta: 4 equally spaced apart pieces were sampled from the inner, middle and outer placental regions. PON2 expression was investigated by Western blotting and real time PCR. Two PON2 forms, one at 62 kDa and one at 43 kDa were found in all samples. No difference in protein expression of either isoform was found between the three sites in either the labour or non-labour group. At the middle site there was a highly significant decrease in PON2 expression in the labour group when compared to the non-labour group for both the 62 kDa form (p = 0.02) and the 43 kDa form (p = 0.006). No spatial differences were found within placentas at the mRNA level in either labour or non-labour. There was, paradoxically, an increase in PON2 mRNA in the labour group at the middle site only. This is the first report to describe changes in PON2 in the placenta in labour. The physiological and pathological significance of these remains to be elucidated but since PON2 is anti-inflammatory further studies are warranted to understand its role

    Multi-transcriptome analysis following an acute skeletal muscle growth stimulus yields tools for discerning global and MYC regulatory networks

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    Myc is a powerful transcription factor implicated in epigenetic reprogramming, cellular plasticity, and rapid growth as well as tumorigenesis. Cancer in skeletal muscle is extremely rare despite marked and sustained Myc induction during loading-induced hypertrophy. Here, we investigated global, actively transcribed, stable, and myonucleus-specific transcriptomes following an acute hypertrophic stimulus in mouse plantaris. With these datasets, we define global and Myc-specific dynamics at the onset of mechanical overload-induced muscle fiber growth. Data collation across analyses reveals an under-appreciated role for the muscle fiber in extracellular matrix remodeling during adaptation, along with the contribution of mRNA stability to epigenetic-related transcript levels in muscle. We also identify Runx1 and Ankrd1 (Marp1) as abundant myonucleus-enriched loading-induced genes. We observed that a strong induction of cell cycle regulators including Myc occurs with mechanical overload in myonuclei. Additionally, in vivo Myc-controlled gene expression in the plantaris was defined using a genetic muscle fiber-specific doxycycline-inducible Myc-overexpression model. We determined Myc is implicated in numerous aspects of gene expression during early-phase muscle fiber growth. Specifically, brief induction of Myc protein in muscle represses Reverbα, Reverbβ, and Myh2 while increasing Rpl3, recapitulating gene expression in myonuclei during acute overload. Experimental, comparative, and in silico analyses place Myc at the center of a stable and actively transcribed, loading-responsive, muscle fiber–localized regulatory hub. Collectively, our experiments are a roadmap for understanding global and Myc-mediated transcriptional networks that regulate rapid remodeling in postmitotic cells. We provide open webtools for exploring the five RNA-seq datasets as a resource to the field

    For People and Planet: Teachers’ Evaluation of an Educational Mobile Game and Resource Pack

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    For People and Planet: An SDG Adventure refers to a freely available Android-based narrative adventure game and teacher resource pack that helps learners see the United Nations Sustainable Development Goals (SDGs) in their day-to-day lives. In this paper, we describe the results of an evaluation of both the game and the resource pack by eight (8) middle school teachers. After playing the game and reading the resource pack, teachers gave their feedback about what they liked best and least about the materials, how they could use these resources for their classes, and how these resources could be improved further. Overall, teachers’ feedback was positive. They complemented the game’s visuals and sound design and appreciated the game’s contextualization. They affirmed the relevance of the game’s contents to their lessons and the usefulness of the teacher resource pack as it provided them with notes, additional activities, and sample assessments. They gave some useful suggestions such as the need for more visual cues within the game and tutorials for the mini-games, and glossary of terms for the teacher resource pack. The game and resource pack underwent some revision following the feedback of the teachers. Performing the user test was essential to ensuring the quality of the game and the resource pack, and to increase the probability that the game will actually be used in schools

    Association between abdominal aortic calcification, bone mineral density and fracture in older women

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    Although a relationship between vascular disease and osteoporosis has been recognized, its clinical importance for fracture risk evaluation remains uncertain. Abdominal aortic calcification (AAC), a recognized measure of vascular disease detected on single‐energy images performed for vertebral fracture assessment, may also identify increased osteoporosis risk. In a prospective 10‐year study of 1,024 older predominantly Caucasian women (mean age 75.0±2.6 years) from the Perth Longitudinal Study of Aging cohort we evaluated the association between AAC, skeletal structure and fractures. AAC and spine fracture were assessed at the time of hip densitometry and heel quantitative ultrasound. AAC was scored 0 to 24 (AAC24) and categorized into; low AAC (score 0 and 1, n=459), moderate AAC (score 2‐5, n=373) and severe AAC (score \u3e 6, n=192). Prevalent vertebral fractures were calculated using the Genant semi‐quantitative method. AAC24 scores were inversely related to hip bone mineral density (BMD) (rs=‐0.077, p=0.013) and heel broadband ultrasound attenuation (rs=‐0.074, p=0.020) and stiffness index (rs=‐0.073, p=0.022). In cross‐sectional analyses women with moderate to severe AAC were more likely to have prevalent fracture and LSI detected lumbar spine but not thoracic spine fractures (Mantel‐Haentzel test of trend p \u3c 0.05). For 10‐year incident clinical fractures and fracture‐related hospitalizations women with moderate to severe AAC (AAC24 score \u3e1) had increased fracture risk (HR 1.48 [1.15‐1.91], p=0.002; HR 1.46 [1.07‐1.99], p=0.019, respectively) compared to women with low AAC. This relationship remained significant after adjusting for age and hip BMD for clinical fractures (HR 1.40 [1.08‐1.81], p=0.010) but was attenuated for fracture‐related hospitalizations (HR 1.33 [0.98‐1.83], p=0.073). In conclusion, older women with more marked AAC are at higher risk of fracture, not completely captured by bone structural predictors. These findings further support the concept that vascular calcification and bone pathology may share similar mechanisms of causation that remain to be fully elucidated
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