Search results for "ddc:"
showing 10 items of 3080 documents
Correlation of the highest-energy cosmic rays with nearby extragalactic objects.
2007
Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above ~ 6x10^{19} electron volts and the positions of active galactic nuclei (AGN) lying within ~ 75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these cosmic rays with at least a 99% confidence level from a prescribed a priori test. The correlation we observed is compatible with the hypothesis that the highest energy particles originate from nearby extragalactic sources whose flux has not been substantially reduced by interaction with the cosmic background radiation. AGN or objects having a similar…
The Children of Risk Communication
2022
For the management of the COVID-19 pandemic, risk communication has been a much-needed preventive and educative action to support citizens – including children – to adopt preventive and health protective measures. However, the COVID-19 pandemic is not the only health concern at hand that has raised concerns about the health status of children and required disease-preventive strategies. Bearing in mind the mental health problems and learning losses reported during the pandemic, in this commentary, we will argue that by now, it is time to consider critically if there could be more space for positive communication and education, both alongside and as an integral part of risk communication, to…
Evolution of lactase persistence: an example of human niche construction
2011
Niche construction is the process by which organisms construct important components of their local environment in ways that introduce novel selection pressures. Lactase persistence is one of the clearest examples of niche construction in humans. Lactase is the enzyme responsible for the digestion of the milk sugar lactose and its production decreases after the weaning phase in most mammals, including most humans. Some humans, however, continue to produce lactase throughout adulthood, a trait known as lactase persistence. In European populations, a single mutation (−13910*T) explains the distribution of the phenotype, whereas several mutations are associated with it in Africa and the Middle …
Epigenetic dysregulation in the developing Down syndrome cortex
2016
Using Illumina 450K arrays, 1.85% of all analyzed CpG sites were significantly hypermethylated and 0.31% hypomethylated in fetal Down syndrome (DS) cortex throughout the genome. The methylation changes on chromosome 21 appeared to be balanced between hypo- and hyper-methylation, whereas, consistent with prior reports, all other chromosomes showed 3–11 times more hyper- than hypo-methylated sites. Reduced NRSF/REST expression due to upregulation of DYRK1A (on chromosome 21q22.13) and methylation of REST binding sites during early developmental stages may contribute to this genome-wide excess of hypermethylated sites. Upregulation of DNMT3L (on chromosome 21q22.4) could lead to de novo methyl…
Induction of strong and persistent MelanA/MART-1-specific immune responses by adjuvant dendritic cell-based vaccination of stage II melanoma patients
2006
A significant percentage of stage II melanoma patients (tumor thickness >1 mm) remain at risk of tumor recurrence after primary tumor excision. In this study, we used tumor antigen-pulsed dendritic cells as an adjuvant for immunization of these “high-risk” melanoma patients after resection of the primary tumor. A total of 13 patients were included and vaccinated 6 times every 14 days with autologous dendritic cells pulsed with a MelanA/MART-1 peptide in combination with a recall antigen. Antigen-specific immune responses were monitored before, during and up to 1 year after the last vaccination. The majority of patients exhibited increased recall antigen-specific CD4+ T cell responses upon v…
Lack of association of a functional catechol-O-methyltransferase gene polymorphism with risk of tobacco smoking: results from a multicenter case-cont…
2013
Background The catechol-O-methyltransferase (COMT) modulates dopaminergic neurotransmission in the prefrontal cortex as well as in the mesolimbic reward system. Since the reward system mediates addictive behavior, the COMT gene is a strong candidate gene regarding the pathophysiology of tobacco dependence and smoking behavior. Because of rather conflicting results in previous studies, the purpose of the present study was to test for association between a functional genetic variant in the COMT gene (single nucleotide polymorphism [SNP] rs4680) and tobacco smoking behavior. Methods In a population-based case-control multicenter study designed for tobacco addiction research, a total of 551 cur…
Seeking the “Beauty Center” in the Brain: A Meta-Analysis of fMRI Studies of Beautiful Human Faces and Visual Art
2020
AbstractThe existence of a common beauty is a long-standing debate in philosophy and related disciplines. In the last two decades, cognitive neuroscientists have sought to elucidate this issue by exploring the common neural basis of the experience of beauty. Still, empirical evidence for such common neural basis of different forms of beauty is not conclusive. To address this question, we performed an activation likelihood estimation (ALE) meta-analysis on the existing neuroimaging studies of beauty appreciation of faces and visual art by non-expert adults (49 studies, 982 participants, meta-data are available at https://osf.io/s9xds/). We observed that perceiving these two forms of beauty a…
Integration of immigrants into a new culture is related to poor sleep quality.
2008
Abstract Background This article reports on the relationship between cultural influences on life style, coping style, and sleep in a sample of female Portuguese immigrants living in Germany. Sleep quality is known to be poorer in women than in men, yet little is known about mediating psychological and sociological variables such as stress and coping with stressful life circumstances. Migration constitutes a particularly difficult life circumstance for women if it involves differing role conceptions in the country of origin and the emigrant country. Methods The study investigated sleep quality, coping styles and level of integration in a sample of Portuguese (N = 48) and Moroccan (N = 64) im…
Dynamic image denoising for voxel-wise quantification with Statistical Parametric Mapping in molecular neuroimaging.
2018
Purpose PET and SPECT voxel kinetics are highly noised. To our knowledge, no study has determined the effect of denoising on the ability to detect differences in binding at the voxel level using Statistical Parametric Mapping (SPM). Methods In the present study, groups of subject-images with a 10%- and 20%- difference in binding of [123I]iomazenil (IMZ) were simulated. They were denoised with Factor Analysis (FA). Parametric images of binding potential (BPND) were produced with the simplified reference tissue model (SRTM) and the Logan non-invasive graphical analysis (LNIGA) and analyzed using SPM to detect group differences. FA was also applied to [123I]IMZ and [11C]flumazenil (FMZ) clinic…
Spontaneous Monokine Release by Alveolar Macrophages in Chronic Sarcoidosis
1991
In pulmonary sarcoidosis an activation of alveolar T lymphocytes and alveolar macrophages (AM) has been demonstrated. There is evidence that in contrast to acute disease a heightened T-cell response cannot be observed in the chronic phase of sarcoidosis. The role of AM in the inflammatory process of chronic sarcoidosis is not yet intensively evaluated. To address this question we measured the release of tumor necrosis factor alpha (TNFα) and interleukin-1 (IL-1) by AM of 39 patients with chronic sarcoidosis (duration > 4 years; 30 active, 9 inactive diseases) without therapy and correlated the monokine release with parameters of T-cell alveolitis and the course of the disease. The T4/T8 …