50 research outputs found
Synaptic Homeostasis and Restructuring across the Sleep-Wake Cycle
Sleep is critical for hippocampus-dependent memory consolidation. However, the underlying
mechanisms of synaptic plasticity are poorly understood. The central controversy is on
whether long-term potentiation (LTP) takes a role during sleep and which would be its specific
effect on memory. To address this question, we used immunohistochemistry to measure
phosphorylation of Ca2+/calmodulin-dependent protein kinase II (pCaMKIIα) in the rat
hippocampus immediately after specific sleep-wake states were interrupted. Control animals
not exposed to novel objects during waking (WK) showed stable pCaMKIIα levels
across the sleep-wake cycle, but animals exposed to novel objects showed a decrease during
subsequent slow-wave sleep (SWS) followed by a rebound during rapid-eye-movement
sleep (REM). The levels of pCaMKIIα during REM were proportional to cortical spindles
near SWS/REM transitions. Based on these results, we modeled sleep-dependent LTP on
a network of fully connected excitatory neurons fed with spikes recorded from the rat hippocampus
across WK, SWS and REM. Sleep without LTP orderly rescaled synaptic weights
to a narrow range of intermediate values. In contrast, LTP triggered near the SWS/REM
transition led to marked swaps in synaptic weight ranking. To better understand the interaction
between rescaling and restructuring during sleep, we implemented synaptic homeostasis
and embossing in a detailed hippocampal-cortical model with both excitatory and
inhibitory neurons. Synaptic homeostasis was implemented by weakening potentiation
and strengthening depression, while synaptic embossing was simulated by evoking LTP
on selected synapses. We observed that synaptic homeostasis facilitates controlled
synaptic restructuring. The results imply a mechanism for a cognitive synergy between
SWS and REM, and suggest that LTP at the SWS/REM transition critically influences the effect
of sleep: Its lack determines synaptic homeostasis, its presence causes synaptic
restructuring.: Support obtained from Financiadora de
Estudos e Projetos (http://www.finep.gov.br/) Grant #
01.06.1092.00 to SR; Conselho Nacional de
Desenvolvimento CientĂfico e TecnolĂłgico (http://
www.cnpq.br/): Grants 481506/2007-1, 481351/2011-
6 and 306604/2012-4 to SR, Coordenação de
Aperfeiçoamento de Pessoal de NĂvel Superior
(http://www.capes.gov.br/) and Ciencias sem
Fronteiras (http://www.cienciasemfronteiras.gov.br/
web/csf/home) to AT and CRC; Fundação de Amparo
Ă Pesquisa do Rio Grande do Norte (http://wwwfapern.rn.gov.br/): Grant Pronem 003/2011 to SR;
Fundação de Amparo à Pesquisa do Estado de São
Paulo (http://www.fapesp.br/): Grant #2013/ 07699-0 -
Center for Neuromathematics to SR; CMP and VRC
supported by post-doctoral fellowships from
Fundação de Amparo à Pesquisa do Rio Grande do
Norte /CNPq. Additional support obtained from the
Federal University of Rio Grande do Norte (www.ufrn.
br); Ministry of Science, Technology and Innovation
(http://www.mcti.gov.br/); Associação Alberto Santos
Dumont de Apoio Ă Pesquisa (http://natalneuro.com/
associacao/index.asp); Pew Latin American Fellows
Program (http://www.pewtrusts.org/en/projects/pewlatin-american-fellows/)
to SR; Informatics
Department of the Instituto Federal de Educação,
CiĂȘncia e Tecnologia do Rio Grande do Norte (http://
portal.ifrn.edu.br/) to WB. The funders had no role in
study design, data collection and analysis, decision to
publish, or preparation of the manuscrip
Continuing education on Paleontology: the experience with the project âWorkshop on Paleontology: fossils inside the classroomâ
The Natural Sciences are essential in the education of citizens aware of the reality in which they live. In this context, Paleontology has an important in basic education, given its multidisciplinary nature, what enables the integrated understanding of the events and phenomena that changed natural environments during the geological history of our planet. In addition, its teaching promotes the awareness of the importance of the fossils as public patrimony, essential for their preservation. Even though current technology allows quick and easy access to information, the selection of subjects and practical activities is often inadequate, as most teachers do not have expertise in paleontology. With this scenario in mind, we created the âWorkshop on Paleontology: fossils inside the classroomâ, culminating in a continuing education workshop, aiming to promote better education of Palentology in schools (basic education). The project already held two workshops, in which several theoretical-practical activities were carried out with teachers and future educators of the public-school network of RibeirĂŁo Preto and Jaboticabal cities, possible multipliers of scientific and patrimonial knowledge within the classroom. After the second workshop, a questionnaire was conducted with students and aimed to assess the course and improve upcoming workshops.O ensino das CiĂȘncias Naturais Ă© essencial na formação de cidadĂŁos como seres cientes da realidade em que vivem. No contexto da formação bĂĄsica, a Paleontologia tem papel importante, dada sua natureza multidisciplinar, e seu estudo auxilia na compreensĂŁo integrada dos eventos e fenĂŽmenos que transformaram ambientes durante a histĂłria geolĂłgica do nosso planeta. Ademais, seu ensino promove a conscientização da importĂąncia dos fĂłsseis como patrimĂŽnio pĂșblico, essencial para sua preservação. Mesmo com a atual facilidade de acesso Ă informação, a seleção de conteĂșdos e prĂĄticas adequadas nem sempre Ă© apropriada, uma vez que poucos professores tĂȘm experiĂȘncia com a Paleontologia. Tendo tais desafios em mente, formulamos o projeto "Oficina de Paleontologia: os fĂłsseis dentro da sala de aula", no formato de um curso de extensĂŁo de educação continuada, com o objetivo de fomentar o ensino elementar de qualidade em Paleontologia nas escolas. Em duas ediçÔes, diversas atividades teĂłrico-prĂĄticas foram realizadas com professores e futuros educadores da rede escolar pĂșblica de RibeirĂŁo Preto e Jaboticabal, possĂveis multiplicadores do conhecimento cientĂfico e patrimonial dentro da sala de aula. ApĂłs o tĂ©rmino da segunda oficina, um questionĂĄrio realizado com os participantes visou avaliar o curso, criando um espaço para crĂticas e sugestĂ”es
Deep learning denoising by dimension reduction: Application to the ORION-B line cubes
Context. The availability of large bandwidth receivers for millimeter radio
telescopes allows the acquisition of position-position-frequency data cubes
over a wide field of view and a broad frequency coverage. These cubes contain
much information on the physical, chemical, and kinematical properties of the
emitting gas. However, their large size coupled with inhomogenous
signal-to-noise ratio (SNR) are major challenges for consistent analysis and
interpretation.Aims. We search for a denoising method of the low SNR regions of
the studied data cubes that would allow to recover the low SNR emission without
distorting the signals with high SNR.Methods. We perform an in-depth data
analysis of the 13 CO and C 17 O (1 -- 0) data cubes obtained as part of the
ORION-B large program performed at the IRAM 30m telescope. We analyse the
statistical properties of the noise and the evolution of the correlation of the
signal in a given frequency channel with that of the adjacent channels. This
allows us to propose significant improvements of typical autoassociative neural
networks, often used to denoise hyperspectral Earth remote sensing data.
Applying this method to the 13 CO (1 -- 0) cube, we compare the denoised data
with those derived with the multiple Gaussian fitting algorithm ROHSA,
considered as the state of the art procedure for data line cubes.Results. The
nature of astronomical spectral data cubes is distinct from that of the
hyperspectral data usually studied in the Earth remote sensing literature
because the observed intensities become statistically independent beyond a
short channel separation. This lack of redundancy in data has led us to adapt
the method, notably by taking into account the sparsity of the signal along the
spectral axis. The application of the proposed algorithm leads to an increase
of the SNR in voxels with weak signal, while preserving the spectral shape of
the data in high SNR voxels.Conclusions. The proposed algorithm that combines a
detailed analysis of the noise statistics with an innovative autoencoder
architecture is a promising path to denoise radio-astronomy line data cubes. In
the future, exploring whether a better use of the spatial correlations of the
noise may further improve the denoising performances seems a promising avenue.
In addition
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Effects of immunomodulatory drugs on depressive symptoms: A mega-analysis of randomized, placebo-controlled clinical trials in inflammatory disorders
Funder: GlaxoSmithKlineFunder: Janssen Research & Development, LLCAbstract: Activation of the innate immune system is commonly associated with depression. Immunomodulatory drugs may have efficacy for depressive symptoms that are co-morbidly associated with inflammatory disorders. We report a large-scale re-analysis by standardized procedures (mega-analysis) of patient-level data combined from 18 randomized clinical trials conducted by Janssen or GlaxoSmithKline for one of nine disorders (N = 10,743 participants). Core depressive symptoms (low mood, anhedonia) were measured by the Short Form Survey (SF-36) or the Hospital Anxiety and Depression Scale (HADS), and participants were stratified into high (N = 1921) versus low-depressive strata based on baseline ratings. Placebo-controlled change from baseline after 4â16 weeks of treatment was estimated by the standardized mean difference (SMD) over all trials and for each subgroup of trials targeting one of 7 mechanisms (IL-6, TNF-α, IL-12/23, CD20, COX2, BLÎłS, p38/MAPK14). Patients in the high depressive stratum showed modest but significant effects on core depressive symptoms (SMD = 0.29, 95% CI [0.12â0.45]) and related SF-36 measures of mental health and vitality. Anti-IL-6 antibodies (SMD = 0.8, 95% CI [0.20â1.41]) and an anti-IL-12/23 antibody (SMD = 0.48, 95% CI [0.26â0.70]) had larger effects on depressive symptoms than other drug classes. Adjustments for physical health outcome marginally attenuated the average treatment effect on depressive symptoms (SMD = 0.20, 95% CI: 0.06â0.35), but more strongly attenuated effects on mental health and vitality. Effects of anti-IL-12/23 remained significant and anti-IL-6 antibodies became a trend after controlling for physical response to treatment. Novel immune-therapeutics can produce antidepressant effects in depressed patients with primary inflammatory disorders that are not entirely explained by treatment-related changes in physical health
Replicable and Coupled Changes in Innate and Adaptive Immune Gene Expression in Two Case-Control Studies of Blood Microarrays in Major Depressive Disorder
BACKGROUND: Peripheral inflammation is often associated with major depressive disorder (MDD), and immunological biomarkers of depression remain a focus of investigation. METHODS: We used microarray data on whole blood from two independent case-control studies of MDD: the GlaxoSmithKline-High-Throughput Disease-specific target Identification Program [GSK-HiTDiP] study (113 patients and 57 healthy control subjects) and the Janssen-Brain Resource Company study (94 patients and 100 control subjects). Genome-wide differential gene expression analysis (18,863 probes) resulted in a p value for each gene in each study. A Bayesian method identified the largest p-value threshold (q = .025) associated with twice the number of genes differentially expressed in both studies compared with the number of coincidental case-control differences expected by chance. RESULTS: A total of 165 genes were differentially expressed in both studies with concordant direction of fold change. The 90 genes overexpressed (or UP genes) in MDD were significantly enriched for immune response to infection, were concentrated in a module of the gene coexpression network associated with innate immunity, and included clusters of genes with correlated expression in monocytes, monocyte-derived dendritic cells, and neutrophils. In contrast, the 75 genes underexpressed (or DOWN genes) in MDD were associated with the adaptive immune response and included clusters of genes with correlated expression in T cells, natural killer cells, and erythroblasts. Consistently, the MDD patients with overexpression of UP genes also had underexpression of DOWN genes (correlation > .70 in both studies). CONCLUSIONS: MDD was replicably associated with proinflammatory activation of the peripheral innate immune system, coupled with relative inactivation of the adaptive immune system, indicating the potential of transcriptional biomarkers for immunological stratification of patients with depression
The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar and APOGEE-2 Data
This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library (MaStar) accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) survey which publicly releases infra-red spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the sub-survey Time Domain Spectroscopic Survey (TDSS) data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey (SPIDERS) sub-survey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated Value Added Catalogs (VACs). This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper (MWM), Local Volume Mapper (LVM) and Black Hole Mapper (BHM) surveys
Childrenâs and adolescentsâ rising animal-source food intakes in 1990â2018 were impacted by age, region, parental education and urbanicity
Animal-source foods (ASF) provide nutrition for children and adolescentsâ physical and cognitive development. Here, we use data from the Global Dietary Database and Bayesian hierarchical models to quantify global, regional and national ASF intakes between 1990 and 2018 by age group across 185 countries, representing 93% of the worldâs child population. Mean ASF intake was 1.9 servings per day, representing 16% of children consuming at least three daily servings. Intake was similar between boys and girls, but higher among urban children with educated parents. Consumption varied by age from 0.6 at <1 year to 2.5 servings per day at 15â19 years. Between 1990 and 2018, mean ASF intake increased by 0.5 servings per week, with increases in all regions except sub-Saharan Africa. In 2018, total ASF consumption was highest in Russia, Brazil, Mexico and Turkey, and lowest in Uganda, India, Kenya and Bangladesh. These findings can inform policy to address malnutrition through targeted ASF consumption programmes.publishedVersio
Incident type 2 diabetes attributable to suboptimal diet in 184 countries
The global burden of diet-attributable type 2 diabetes (T2D) is not well established. This risk assessment model estimated T2D incidence among adults attributable to direct and body weight-mediated effects of 11 dietary factors in 184 countries in 1990 and 2018. In 2018, suboptimal intake of these dietary factors was estimated to be attributable to 14.1 million (95% uncertainty interval (UI), 13.8â14.4 million) incident T2D cases, representing 70.3% (68.8â71.8%) of new cases globally. Largest T2D burdens were attributable to insufficient whole-grain intake (26.1% (25.0â27.1%)), excess refined rice and wheat intake (24.6% (22.3â27.2%)) and excess processed meat intake (20.3% (18.3â23.5%)). Across regions, highest proportional burdens were in central and eastern Europe and central Asia (85.6% (83.4â87.7%)) and Latin America and the Caribbean (81.8% (80.1â83.4%)); and lowest proportional burdens were in South Asia (55.4% (52.1â60.7%)). Proportions of diet-attributable T2D were generally larger in men than in women and were inversely correlated with age. Diet-attributable T2D was generally larger among urban versus rural residents and higher versus lower educated individuals, except in high-income countries, central and eastern Europe and central Asia, where burdens were larger in rural residents and in lower educated individuals. Compared with 1990, global diet-attributable T2D increased by 2.6 absolute percentage points (8.6 million more cases) in 2018, with variation in these trends by world region and dietary factor. These findings inform nutritional priorities and clinical and public health planning to improve dietary quality and reduce T2D globally.publishedVersio
Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo
Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201