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Back to the Future. Metabolic Effects of a 4-Day Outdoor Trip Under Simulated Paleolithic Conditions â New Insights from The Eifel Study
Background: The observation that the emergence of common Western diseases takes place with much greater prevalence as societies migrate from natural-living cultures to modernized societies, has been well documented. For approximately 84,000 generations humans lived under hunter-gatherer conditions but recently endured dramatic change from our native lifestyle with the occurrence of the agricultural, industrial, and digital revolutions. The massive technological advancement that occurred within a relatively recent timeframe enabled humans to live in manner that is remarkably different than our pre-agricultural past. Consequently, the shift from a natural to a modern lifestyle likely promotes a gene-environment mismatch which causes metabolic dysregulation which causes disease.Methods: Using a within-participant design, we examined whether, compared to baseline, changes in lifestyle towards a more Paleolithic-style pattern, for a four-day and four-night period related to changes in a variety of metabolic parameters. Two groups of 14 volunteers were isolated for a period of four days and four nights in the natural park SĂŒdeifel on the borders between Germany and Luxembourg. Participants lived outdoors without tents. The daily hiking performance was 16.4 km (â 24963 steps/day) and the daily activity time 5.49 h/day by a mean caloric intake of 1747 kcal/day.Results: After four days of simulated Paleolithic conditions, body weight (-2.9%), body mass index (-2.7%), body fat (-10.4%), visceral fat (-13.6%) and waist-hip-ratio (-2.2%) significantly decreased, while muscle mass significantly increased (+2,3%). Additionally, fasting glucose (-6.5%), basal insulin (-44.4%), homeostasis model assessment-index (-49.3%) and fatty liver index (-41%) significantly dropped. In contrast, C-reactive protein, significantly increased (+67.1%).Conclusion: Our study indicates that a short nature trip, where modern humans adjust their behavioral patterns to simulate a more Paleolithic-like condition, could serve as an effective strategy to help prevent or improve modern metabolic disease. Particularly, the major findings of an expeditious reduction of homeostasis model assessment-index and fatty liver index scores in only four days reveal the potential for meaningful benefits with such an intervention, even when compared to the effects of longer-term, single-intervention studies such as dietary or fitness programs on similar metabolic parameters
To Restore Health, âDo we Have to Go Back to the Future?â The Impact of a 4-Day Paleolithic Lifestyle Change on Human Metabolism â a Pilot Study.
On their way from the Stone Age via the Agricultural Revolution to current high-tech conditions, humans lost their primal foraging behavior. Today, energy expenditure is not necessary anymore for gathering nor hunting, and metabolic diseases are epidemically arising wherever our original Paleolithic lifestyle is turning into a modern sedentary lifestyle. In this pilot study, we followed through the concept that a radical change towards a Paleolithic hunter-gatherer lifestyle could serve as therapy against any metaflammatory disease, even in the short term. Thirteen healthy adult volunteers were transferred to the DELUX National Park (Germany and Luxembourg) for four days and three nights, where Stone Age conditions where mimicked. Thirty-eight biochemical and bioelectrical parameters were measured from participants before and after this relocation. Body weight (-3,9%), body fat (-7,5%), body mass index (-3,8%), visceral fat area (-14,4%) and metaflammation-related parameters (fasting glucose = -18,2%; fasting insulin = -50,1%; HOMA = -57,8%) decreased significantly. C-reactive protein, as the main indicator for low-grade inflammation, increased up to an average of 169,6 %. Our data show that returning to our Paleolithic roots may have positive effects on risk factors commonly associated with metabolic disorders, such as obesity and type 2 diabetes. These findings may lead the way to further research to answer the question whether the already existing metabolic conditions and/or autoimmune and neuroinflammatory diseases could be influenced by a Paleolithic lifestyle
Radio wave propagation and single-cell coverage prediction of broadband radio access systems including passive reflectors, Journal of Telecommunications and Information Technology, 2001, nr 2
This paper presents the scheme of a software planing tool for single microcells of broadband radio access systems operating at millimeter waves, providing local multi- point distribution services (LMDS), particularly in urban or suburban areas. The aim of this planing tool is to provide operators with information, which supports the assessment of the profitability by calculating link budgets and the area coverage and by roughly estimating the maximum number of potential customers, i.e. the total number of households in a certain area, as well as the number of customers (house-holds) which will actually be covered from a site. A house-hold is here considered as a single apartment or flat, thus a building usually consists of several households. This novel household-estimation model is able to estimate the number of households based only on the 3D-data of buildings, without using residential data. Besides the optimization of line-of-sight (LOS) coverage, also the possibility is considered to enhance the coverage into shadowed areas by using optimized reflectors as passive repeaters up to distances of 1 km from the base station, depending on the system margin and the rain climate zone. All calculations are based on 3D-databases of both, buildings and vegetation
Tunneling and propagation of vacuum bubbles on dynamical backgrounds
In the context of bubble universes produced by a first-order phase transition
with large nucleation rates compared to the inverse dynamical time scale of the
parent bubble, we extend the usual analysis to non-vacuum backgrounds. In
particular, we provide semi-analytic and numerical results for the modified
nucleation rate in FLRW backgrounds, as well as a parameter study of bubble
walls propagating into inhomogeneous (LTB) or FLRW spacetimes, both in the
thin-wall approximation. We show that in our model, matter in the background
often prevents bubbles from successful expansion and forces them to collapse.
For cases where they do expand, we give arguments why the effects on the
interior spacetime are small for a wide range of reasonable parameters and
discuss the limitations of the employed approximations.Comment: 29 pages, 8 figures, typos corrected, matches published versio
The sedentary (r)evolution:Have we lost our metabolic flexibility?
During the course of evolution, up until the agricultural revolution, environmental fluctuations forced the human species to develop a flexible metabolism in order to adapt its energy needs to various climate, seasonal and vegetation conditions. Metabolic flexibility safeguarded human survival independent of food availability. In modern times, humans switched their primal lifestyle towards a constant availability of energy-dense, yet often nutrient-deficient, foods, persistent psycho-emotional stressors and a lack of exercise. As a result, humans progressively gain metabolic disorders, such as the metabolic syndrome, type 2 diabetes, non-alcoholic fatty liver disease, certain types of cancer, cardiovascular disease and AlzheimerÂŽs disease, wherever the sedentary lifestyle spreads in the world. For more than 2.5 million years, our capability to store fat for times of food shortage was an outstanding survival advantage. Nowadays, the same survival strategy in a completely altered surrounding is responsible for a constant accumulation of body fat. In this article, we argue that the metabolic epidemic is largely based on a deficit in metabolic flexibility. We hypothesize that the modern energetic inflexibility, typically displayed by symptoms of neuroglycopenia, can be reversed by re-cultivating suppressed metabolic programs, which became obsolete in an affluent environment, particularly the ability to easily switch to ketone body and fat oxidation. In a simplified model, the basic metabolic programs of humansâ primal hunter-gatherer lifestyle are opposed to the current sedentary lifestyle. Those metabolic programs, which are chronically neglected in modern surroundings, are identified and conclusions for the prevention of chronic metabolic diseases are drawn
Working Group on Governance of the Regional Database & Estimation System (WGRDBES-GOV; Outputs from 2020 meeting)
The Working Group on Governance of the Regional Database & Estimation System (WGRDBESGOV) provides the governance function for both the existing Regional Database (RDB) and the new Regional Database & Estimation System (RDBES) that is currently in development. It is composed of representatives from ICES member countries and EU Regional Coordination Groups (RCGs). In this report, the WGRDBESGOV reviews the RDBES developments performed during 2020 and plans for the work required in 2021 and beyond. It also considers how RDB data has been used and proposes changes required to the current Data Policy. The RDBES is currently planned to replace both the existing ICES InterCatch and RDB database systems and has an important part to play in increasing transparency and improving the quality of stock assessment within ICES. To this end, two workshops have been planned for 2021 which will help data submitters with the transition to the new system. A new working group is also proposed to enable the ICES community to move forward with estimation using the RDBES data model. Following on from the data call issued in 2020, another test data call is also planned for 2021 which will give further motivation for people to become involved and provide a robust test of the process. The RDB and RDBES must ensure that data can be used by the RCGs and authorised groups in ICES whilst ensuring that only permitted users have access to the confidential data â the rules relating to this have previously been defined in the RDB Data Policy. In line with discussions at the ICES Data and Information Group (DIG), it is proposed to split the current Data Policy into two new documents: a Data License, and a Data Governance document. It is important to remember that the ultimate success of the RDBES will rely on the effort and contributions from a large number of people in the wider ICES/EU data collection community and not just the relatively small groups who attend the WGRDBESGOV or Core Group meetings. The WGRDBESGOV continues to encourage these contributions
Are risk estimates biased in follow-up studies of psychosocial factors with low base-line participation?
Violent aggression predicted by multiple pre-adult environmental hits
Early exposure to negative environmental impact shapes individual behavior and potentially contributes to any mental disease. We reported previously that accumulated environmental risk markedly decreases age at schizophrenia onset. Follow-up of matched extreme group individuals (â€1 vs. â„3 risks) unexpectedly revealed that high-risk subjects had >5 times greater probability of forensic hospitalization. In line with longstanding sociological theories, we hypothesized that risk accumulation before adulthood induces violent aggression and criminal conduct, independent of mental illness. We determined in 6 independent cohorts (4 schizophrenia and 2 general population samples) pre-adult risk exposure, comprising urbanicity, migration, physical and sexual abuse as primary, and cannabis or alcohol as secondary hits. All single hits by themselves were marginally associated with higher violent aggression. Most strikingly, however, their accumulation strongly predicted violent aggression (odds ratio 10.5). An epigenome-wide association scan to detect differential methylation of blood-derived DNA of selected extreme group individuals yielded overall negative results. Conversely, determination in peripheral blood mononuclear cells of histone-deacetylase1 mRNA as âumbrella mediatorâ of epigenetic processes revealed an increase in the high-risk group, suggesting lasting epigenetic alterations. Together, we provide sound evidence of a disease-independent unfortunate relationship between well-defined pre-adult environmental hits and violent aggression, calling for more efficient prevention
Violent aggression predicted by multiple pre-adult environmental hits
Early exposure to negative environmental impact shapes individual behavior and potentially contributes to any mental disease. We reported previously that accumulated environmental risk markedly decreases age at schizophrenia onset. Follow-up of matched extreme group individuals (â€1 vs. â„3 risks) unexpectedly revealed that high-risk subjects had >5 times greater probability of forensic hospitalization. In line with longstanding sociological theories, we hypothesized that risk accumulation before adulthood induces violent aggression and criminal conduct, independent of mental illness. We determined in 6 independent cohorts (4 schizophrenia and 2 general population samples) pre-adult risk exposure, comprising urbanicity, migration, physical and sexual abuse as primary, and cannabis or alcohol as secondary hits. All single hits by themselves were marginally associated with higher violent aggression. Most strikingly, however, their accumulation strongly predicted violent aggression (odds ratio 10.5). An epigenome-wide association scan to detect differential methylation of blood-derived DNA of selected extreme group individuals yielded overall negative results. Conversely, determination in peripheral blood mononuclear cells of histone-deacetylase1 mRNA as 'umbrella mediator' of epigenetic processes revealed an increase in the high-risk group, suggesting lasting epigenetic alterations. Together, we provide sound evidence of a disease-independent unfortunate relationship between well-defined pre-adult environmental hits and violent aggression, calling for more efficient prevention
The cross-sectional GRAS sample: A comprehensive phenotypical data collection of schizophrenic patients
<p>Abstract</p> <p>Background</p> <p>Schizophrenia is the collective term for an exclusively clinically diagnosed, heterogeneous group of mental disorders with still obscure biological roots. Based on the assumption that valuable information about relevant genetic and environmental disease mechanisms can be obtained by association studies on patient cohorts of ℠1000 patients, if performed on detailed clinical datasets and quantifiable biological readouts, we generated a new schizophrenia data base, the GRAS (Göttingen Research Association for Schizophrenia) data collection. GRAS is the necessary ground to study genetic causes of the schizophrenic phenotype in a 'phenotype-based genetic association study' (PGAS). This approach is different from and complementary to the genome-wide association studies (GWAS) on schizophrenia.</p> <p>Methods</p> <p>For this purpose, 1085 patients were recruited between 2005 and 2010 by an invariable team of traveling investigators in a cross-sectional field study that comprised 23 German psychiatric hospitals. Additionally, chart records and discharge letters of all patients were collected.</p> <p>Results</p> <p>The corresponding dataset extracted and presented in form of an overview here, comprises biographic information, disease history, medication including side effects, and results of comprehensive cross-sectional psychopathological, neuropsychological, and neurological examinations. With >3000 data points per schizophrenic subject, this data base of living patients, who are also accessible for follow-up studies, provides a wide-ranging and standardized phenotype characterization of as yet unprecedented detail.</p> <p>Conclusions</p> <p>The GRAS data base will serve as prerequisite for PGAS, a novel approach to better understanding 'the schizophrenias' through exploring the contribution of genetic variation to the schizophrenic phenotypes.</p
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