48 research outputs found
First in the Nation in Education : Final Report,1984.
No full textThis report is one step in an ongoing process of change and is a plea for commitment for high standards in education in Iowa. Contains the final reports of the six subcommittees as adopted by the Excellence in Education Task Force, and the five recommendations made by the Task Force
Adenine DNA methylation, 3D genome organization, and gene expression in the parasite Trichomonas vaginalis
No full textTrichomonas vaginalis is a common sexually transmitted parasite that colonizes the human urogenital tract causing infections that range from asymptomatic to highly inflammatory. Recent works have highlighted the importance of histone modifications in the regulation of transcription and parasite pathogenesis. However, the nature of DNA methylation in the parasite remains unexplored. Using a combination of immunological techniques and ultrahigh-performance liquid chromatography (UHPLC), we analyzed the abundance of DNA methylation in strains with differential pathogenicity demonstrating that N6-methyladenine (6mA), and not 5‐methylcytosine (5mC), is the main DNA methylation mark in T. vaginalis. Genome-wide distribution of 6mA reveals that this mark is enriched at intergenic regions, with a preference for certain superfamilies of DNA transposable elements. We show that 6mA in T. vaginalis is associated with silencing when present on genes. Interestingly, bioinformatics analysis revealed the presence of transcriptionally active or repressive intervals flanked by 6mA-enriched regions, and results from chromatin conformation capture (3C) experiments suggest these 6mA flanked regions are in close spatial proximity. These associations were disrupted when parasites were treated with the demethylation activator ascorbic acid. This finding revealed a role for 6mA in modulating three-dimensional (3D) chromatin structure and gene expression in this divergent member of the Excavata.Fil: Lizarraga, Ayelen. Universidad Nacional de San Martin. Instituto Tecnologico de Chascomus. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - la Plata. Instituto Tecnologico de Chascomus.; ArgentinaFil: O'Brown, Zach Klapholz. Harvard Medical School; Estados UnidosFil: Boulias, Konstantinos. Harvard Medical School; Estados UnidosFil: Roach, Lara. Harvard Medical School; Estados UnidosFil: Greer, Eric Lieberman. Harvard Medical School; Estados UnidosFil: Johnson, Patricia J.. University of California at Los Angeles; Estados UnidosFil: Strobl Mazzulla, Pablo H.. Universidad Nacional de San Martin. Instituto Tecnologico de Chascomus. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - la Plata. Instituto Tecnologico de Chascomus.; ArgentinaFil: de Miguel, Natalia. Universidad Nacional de San Martin. Instituto Tecnologico de Chascomus. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - la Plata. Instituto Tecnologico de Chascomus.; Argentin
18S rRNA methyltransferases DIMT1 and BUD23 drive intergenerational hormesis
No full textHeritable non-genetic information can regulate a variety of complex phenotypes. However, what specific non-genetic cues are transmitted from parents to their descendants are poorly understood. Here, we perform metabolic methyl-labeling experiments to track the heritable transmission of methylation from ancestors to their descendants in the nematode Caenorhabditis elegans (C. elegans). We find heritable methylation in DNA, RNA, proteins, and lipids. We find that parental starvation elicits reduced fertility, increased heat stress resistance, and extended longevity in fed, naïve progeny. This intergenerational hormesis is accompanied by a heritable increase in N6\u27-dimethyl adenosine (
Parameter and state model reduction for Bayesian statistical inverse problems
No full textThesis (S.M.)--Massachusetts Institute of Technology, Computation for Design and Optimization Program, 2009.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student submitted PDF version of thesis.Includes bibliographical references (p. 113-118).Decisions based on single-point estimates of uncertain parameters neglect regions of significant probability. We consider a paradigm based on decision-making under uncertainty including three steps: identification of parametric probability by solution of the statistical inverse problem, propagation of that uncertainty through complex models, and solution of the resulting stochastic or robust mathematical programs. In this thesis we consider the first of these steps, solution of the statistical inverse problem, for partial differential equations (PDEs) parameterized by field quantities. When these field variables and forward models are discretized, the resulting system is high-dimensional in both parameter and state space. The system is therefore expensive to solve. The statistical inverse problem is one of Bayesian inference. With assumption on prior belief about the form of the parameter and an assignment of normal error in sensor measurements, we derive the solution to the statistical inverse problem analytically, up to a constant of proportionality. The parametric probability density, or posterior, depends implicitly on the parameter through the forward model. In order to understand the distribution in parameter space, we must sample. Markov chain Monte Carlo (MCMC) sampling provides a method by which a random walk is constructed through parameter space. By following a few simple rules, the random walk converges to the posterior distribution and the resulting samples represent draws from that distribution. This set of samples from the posterior can be used to approximate its moments.(cont.) In the multi-query setting, it is computationally intractable to utilize the full-order forward model to perform the posterior evaluations required in the MCMC sampling process. Instead, we implement a novel reduced-order model which reduces in parameter and state. The reduced bases are generated by greedy sampling. We iteratively sample the field in parameter space which maximizes the error in full-order and current reduced-order model outputs. The parameter is added to its basis and then a high-fidelity forward model is solved for the state, which is then added to the state basis. The reduction in state accelerates posterior evaluation while the reduction in parameter allows the MCMC sampling to be conducted with a simpler, non-adaptive 3 Metropolis-Hastings algorithm. In contrast, the full-order parameter space is high-dimensional and requires more expensive adaptive methods. We demonstrate for the groundwater inverse problem in 1-D and 2-D that the reduced-order implementation produces accurate results with a factor of three speed up even for the model problems of dimension N ~~500. Our complexity analysis demonstrates that the same approach applied to the large-scale models of interest (e.g. N > 10⁴) results in a speed up of three orders of magnitude.by Chad Eric Lieberman.S.M
Scientific production on inclusive education and physical education: a bibliometric analysis
No full textThe aim of this study was to develop a bibliometric analysis of the scientific production on inclusive education and physical education, focusing on productivity, topics and collaboration. Articles and reviews related to inclusive education and physical education published until 2018 in ERIC, PsycINFO, Scopus, SPORTDiscus and Web of Science databases were included. Regarding results, 664 documents published from 1969 to 2018 were discovered. Documents approaching from sociology (183) and focused on inclusive cultures (63.1%) were the most represented. The average percentage of collaboration was 76.96%. Block was the most productive author while Lieberman achieved the highest number of collaborators. Almost half of the scientific output was published in 13 journals, three of them specifically dedicated to adapted physical activity. In summary, the scientific production on inclusive education and physical education has been mainly published
during the last decade, in collaboration, focused on inclusive cultures and playing social sciences a key role for studying it, reflecting the interests and approaches of scholars and their patterns of collaboration. The emergence of inclusive education from the social and political spheres, the misunderstanding of this concept and its low educational consolidation have contributed to an increasing production of studies about inclusive culture
Transgenerational adaptation to hypoxia
No full textEpigenetic inheritance alerts naïve descendants to prepare for stresses that could still be present, whereas distant descendants return to a basal state after several generations without stress. However, organisms are frequently exposed to stresses successively across generations. We found that parental hypoxia exposure increased P0 longevity, caused intergenerational lipid reduction, and elicited transgenerational fertility reduction that was dependent on generationally transmitted small RNAs. Here, we find tha
