2,661 research outputs found
Reorganization of Brain Networks as a Substrate of Resilience: An Analysis of Cytochrome c Oxidase Activity in Rats.
The unpredictable chronic mild stress (UCMS) model has been used to induce depressive-like symptoms in animal models, showing adequate predictive validity. Our work aims to evaluate the effects of environmental enrichment (EE) on resilience in this experimental model of depression. We also aim to assess changes in brain connectivity using cytochrome c oxidase histochemistry in cerebral regions related to cognitive-affective processes associated with depressive disorder: dorsal hippocampus, prefrontal cortex, amygdala, accumbens, and habenula nuclei. Five groups of rats were used: UCMS, EE, EE + UCMS (enrichment + stress), BG (basal level of brain activity), and CONT (behavioral tests only). We assessed the hedonic responses elicited by sucrose solution using a consumption test; the anxiety level was evaluated using the elevated zero maze test, and the unconditioned fear responses were assessed by the cat odor test. The behavioral results showed that the UCMS protocol induces elevated anhedonia and anxiety. But these responses are attenuated previous exposure to EE. Regarding brain activity, the UCMS group showed greater activity in the habenula compared to the EE + UCMS group. EE induced a functional reorganization of brain activity. The EE + UCMS and UCMS groups showed different patterns of connections between brain regions. Our results showed that EE favors greater resilience and could reduce vulnerability to disorders such as depression and anxiety, modifying metabolic brain activity.post-print2,38 M
The impact of financial insecurity on self-reported health: Europe in cross-national perspective
Using the EU-SILC 2008 module on over-indebtedness and financial exclusion, this paper analyses how perceived future-orientated economic insecurity alters individual self-assessed health (SAH), once controlling for past and current financial situation in a range of European countries. Those effects differ by gender and by country. Our results also suggest that country characteristics explain a larger part of the unknown variability of individual levels of SAH than individual-household characteristics. Thus, our findings might be of help in designing the most effective policies intended to alleviate the individual welfare costs of perceived financial insecurity provoked by upcoming business-cycle downturnsPID2019111765GB-I0
Photon to axion conversion during Big Bang Nucleosynthesis
We investigate how the resonant conversion at a temperature -
keV of a fraction of the CMB photons into an axion-like majoron affects BBN.
The scenario, that assumes the presence of a primordial magnetic field and the
subsequent decay of the majorons into neutrinos at eV, has been
proposed to solve the tension. We find two main effects. First, since we
lose photons to majorons at , the baryon to photon ratio is smaller at
the beginning of BBN than during decoupling and structure
formation (). This relaxes the mismatch between the
observed deuterium abundance and the one predicted by the standard CDM
model. Second, since the conversion implies a sudden drop in the temperature of
the CMB during the final phase of BBN, it interrupts the synthesis of lithium
and beryllium and reduces their final abundance, possibly alleviating the
lithium problem.Comment: 12 pages, 3 figures; new section added, matches version accepted by
JCA
Modelling and in vivo evaluation of tendon forces and strain in dynamic rehabilitation exercises: a scoping review
Objectives Although exercise is considered the preferred approach for tendinopathies, the actual load that acts on the tendon in loading programmes is usually unknown. The objective of this study was to review the techniques that have been applied in vivo to estimate the forces and strain that act on the human tendon in dynamic exercises used during rehabilitation.
Design Scoping review.
Data sources Embase, PubMed, Web of Science and Google Scholar were searched from database inception to February 2021.
Eligibility criteria Cross-sectional studies available in English or Spanish language were included if they focused on evaluating the forces or strain of human tendons in vivo during dynamic exercises. Studies were excluded if they did not evaluate tendon forces or strain; if they evaluated running, walking, jumping, landing or no dynamic exercise at all; and if they were conference proceedings or book chapters.
Data extraction and synthesis Data extracted included year of publication, study setting, study population characteristics, technique used and exercises evaluated. The studies were grouped by the types of techniques and the tendon location.
Results Twenty-one studies were included. Fourteen studies used an indirect methodology based on inverse dynamics, nine of them in the Achilles and five in the patellar tendon. Six studies implemented force transducers for measuring tendon forces in open carpal tunnel release surgery patients. One study applied an optic fibre technique to detect forces in the patellar tendon. Four studies measured strain using ultrasound-based techniques.
Conclusions There is a predominant use of inverse dynamics, but force transducers, optic fibre and estimations from strain data are also used. Although these tools may be used to make general estimates of tendon forces and strains, the invasiveness of some methods and the loss of immediacy of others make it difficult to provide immediate feedback to the individuals.This work is part of a government-funded project supported by the University Teaching Training Programme (FPU) of the Ministry of Science, Innovation and Universities of Spain. Grant number: FPU17/00161. The University of Malaga has supported this study with the contribution of funds to support its publication in open access
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