80 research outputs found
Using genealogical trees to examine admixture between modern humans and Neandertals
No full textThis thesis uses genealogical trees to identify, date, and quantify patterns of admixture between Neandertals and individual modern human populations, using a combination of high quality data and parametric methodology. Previous methods on this subject have either approximated features of trees, or inferred them indirectly. Here, genealogical trees are used directly to understand the admixture process between humans and Neandertals by extending a recently developed method named CEPHi: Coalescent Estimation of Population History. CEPHi uses recombinationally cold regions of the human genome to build genealogical trees specifying the relationships between individuals in two input populations (one Neandertal, one human), including estimated population size histories, split times, and coalescence and mutation times.
Using CEPHi, a Neandertal-human population split time of ∼712,000 years in the past is estimated, as well as uncovering loci introduced by Neandertal-human admixture, revealing distinct bimodal distributions of estimated coalescence times between non-African and Neandertal haplotypes. A Neandertal population history is inferred, from the time of their split with humans up to ∼50,000 years ago (the fossil age), showing this archaic species to have suffered a bottleneck at this time, consistent with leaving Africa, followed by a further reduction to extinction.
Contrasting African-Neandertal and Eurasian-Neandertal analyses are used to define admixture using genealogical trees, and test our procedures in CEPHi via coalescent-based simulations. This region-level definition of admixture is used to specify sets of introgressed coldspots across 13 modern human populations. These sets are compared between pairs of populations, revealing information about the possible timing of interactions between Neandertals and modern humans, and sharing of admixture events between human groups, especially with respect to the split time between European and Asian populations. Online sets of introgressed regions for each of the four continents in our dataset are provided: African, American, Asian, and European.
Finally, in order to investigate the variation in time of contact between Neandertals and individual human populations, a novel method is described and implemented which dates admixture between individual human populations and Neandertals, using information from genealogical trees. Dates of admixture are estimated as ~50-60,000 years in the past in European populations, and ∼80-90,000 years in the past in Asian populations, suggestive of potentially somewhat distinct histories between European and Asian populations. This method can be applied to date any set of introgressed regions, including those shared between particular populations, enabling a clearer picture of the joint evolutionary history of modern humans, Neandertals, and other archaic species.</p
Schreibst du noch oder tippst du schon? Die Auswirkungen der Schreibmodalität auf die Gedächtnisleistung
No full textReplikation von Frangou S.-M., Ruokamo H., Parviainen T. & Wikgren J. (2018). Can you put your finger on it? The effects of writing modality on Finnish students’ recollection. Writing Systems Research, 10 (2), 82-94
The Current Status of Women in Psychiatry in Europe
No full textFor more than two decades, psychiatry has retained its position amongst the medical specialties with the highest proportion of women entering residency programs. The percentage of women in junior academic positions in psychiatry is also high and consistently higher than that of men. However, the number of women in positions of leadership remains disproportionally low at around 5% with no evidence of improvement over time. The phenomenon of female under-representation is not unique to psychiatry or academia. Women are under-represented in all fields of leadership and this is a matter of wider societal concern. In this presentation, I will discuss external and internal barriers that women face and detail positive actions that can help women succeed in their careers.Disclosure of interestThe author has edited and co-authored a book on “Women in Academic Psychiatry: A mind to Succeed”</jats:sec
Diffusivity of α-, β-, γ-cyclodextrin and the inclusion complex of β-cyclodextrin: Ibuprofen in aqueous solutions; A molecular dynamics simulation study
No full textCyclodextrins (CDs) are widely used in drug delivery, catalysis, food and separation processes. In this work, a comprehensive simulation study on the diffusion of the native α-, β- and γ-CDs in aqueous solutions is carried out using Molecular Dynamics simulations. The effect of the system size on the computed self-diffusivity is investigated and it is found that the required correction can be as much as 75% of the final value. The effect of the water force field is examined and it is shown that the q4md-CD/TIP4P/2005 force field combination predicts the experimentally measured self-diffusion coefficients of CDs very accurately. The self-diffusion coefficients of the three native CDs were also computed in aqueous-NaCl solutions using the Joung and Cheatham (JC) and the Madrid-2019 force fields. It is found that Na+ ions have higher affinity towards the CDs when the JC force field is used and for this reason the predicted diffusivity of CDs is lower compared to simulations using the Madrid-2019 force field. As a model system for drug delivery and waste-water treatment applications, the diffusion of the β-CD:Ibuprofen inclusion complex in water is studied. In agreement with experiments for similar components, it is shown that the inclusion complex and the free β-CD have almost equal self-diffusion coefficients. Our analysis revealed that this is most likely caused by the almost full inclusion of the ibuprofen in the cavity of the β-CD. Our findings show that Molecular Dynamics simulation can be used to provide reasonable diffusivity predictions, and to obtain molecular-level understanding useful for industrial applications of CDs.Engineering Thermodynamic
Family counts: deciding when to murder among the Icelandic Vikings
No full textAbstractIn small scale societies, lethal attacks on another individual usually invite revenge by the victim's family. We might expect those who perpetrate such attacks to do so only when their own support network (mainly family) is larger than that of the potential victim so as to minimise the risk of retaliation. Using data from Icelandic family sagas, we show that this prediction holds whether we consider biological kin or affinal kin (in-laws): on average, killers had twice as many relatives as their victims. These findings reinforce the importance of kin as a source of implicit protection even when they are not physically present. The results also support Hughes' (1988) claim that affines are biological kin because of the shared genetic interests they have in the offspring generation
Laughter influences social bonding but not prosocial generosity to friends and strangers
No full textHumans deploy a number of specific behaviours for forming social bonds, one of which is laughter. However, two questions have not yet been investigated with respect to laughter: (1) Does laughter increase the sense of bonding to those with whom we laugh? and (2) Does laughter facilitate prosocial generosity? Using changes in pain threshold as a proxy for endorphin upregulation in the brain and a standard economic game (the Dictator Game) as an assay of prosociality, we show that laughter does trigger the endorphin system and, through that, seems to enhance social bonding, but it does not reliably influence donations to others. This suggests that social bonding and prosociality may operate via different mechanisms, or on different time scales, and relate to different functional objectives
Data from 617 healthy participants performing the Iowa gambling task: a "many labs" collaboration
No full textThis data pool (N = 617) comes from 10 independent studies assessing performance of healthy participants (i.e., no known neurological impairments) on the Iowa gambling task (IGT) - a task measuring decision making under uncertainty in an experimental context. Participants completed a computerized version of the IGT consisting of 95 - 150 trials. The data consist of the choices of each participant on each trial, and the resulting rewards and losses. The data are stored as .rdata, .csv, and .txt files, and can be reused to (1) analyze IGT performance of healthy participants; (2) create a "super control group"; or (3) facilitate model-comparison efforts
The influence of diabetes on degree of abdominal aortic aneurysm tissue inflammation
No full textAbdominal aortic aneurysm (AAA) progression and disease resistance are related to transmural degenerative processes and an inflammatory infiltration (INF). Diabetes is associated with low prevalence and growth rate of AAA. We sought to characterize INF in established AAA (INFAAA), in diabetic patients. From 89 male patients aged 52 to 83 years, aneurysm specimens obtained at open asymptomatic nonruptured AAA repair were graded for INF and immunostained using antibodies against T-lymphocytes (CD3) and macrophages (CD68). Diabetic patients had an odds ratio (OR) 3.8, 95% confidence interval ([CI] 1.14-12.96), P =.03, of experiencing above-median INFAAA. These associations were affected by serum glucose (SG) levels (OR 3.6, 95% CI [0.72-18.77]; P =.1). Macrophage subpopulations higher in diabetic patients (1.44 ± 0.78 versus 0.98 ± 0.76; P =.02) were correlated with SG (r =.21, P =.044). Abdominal aortic aneurysms in diabetic patients are associated with higher INF. Macrophage densities are correlated with SG. © The Author(s) 2010
Fig 2 -
No full textMean±se (a) Change in pain threshold and (b) total donations, for men (unfilled symbols) and women (filled symbols) in Experiment 1.</p
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