126 research outputs found
Illegal Immigration Backlash Worries, Divides Latinos
Compares survey responses of Latinos/Hispanics with those of the general population and by nativity on topics such as immigration policy, illegal immigrants' impact on other Latinos/Hispanics, and political solidarity between the native- and foreign-born
Prediction of clinical height gain from surgical posterior correction of idiopathic scoliosis
OBJECTIVE: The best predictors of height gain due to surgical correction are the number of fused vertebrae and the degrees of the corrected Cobb angle. Existing studies of predictive models measured the radiographic spinal height and did not report the clinical height gain. The aims of this study were to determine the best predictive factors of clinical height gain before surgical correction, construct a predictive model using patient population data for machine learning, and test the performance of this model on a validation population.METHODS: The authors reviewed 145 medical records of consecutive patients who underwent surgery that included placement of posterior spinal instrumentation and fusion for idiopathic scoliosis between 2012 and 2016. Standing and sitting clinical heights were measured before and after surgery in patients who had been surgically treated under similar conditions. Multivariate analysis was then performed and the results were used to develop a predictive model for height gain after surgery. The data from the included patients were randomly assigned to a learning set or a test set. RESULTS : In total, 116 patients were included in the analysis, for whom the average postoperative clinical height gain in a standing position was 4.2 ± 1.8 cm (range 0–11 cm). The best prediction model was calculated as follows: standing clinical height gain (cm) = 1 − 0.023 × sitting clinical height (cm) − 0.19 × Risser stage + 0.058 × Cobb preoperative angle (°) + 0.021 × T5–12 kyphosis (°) + 0.14 × number of levels fused. In the validation cohort, 91% of the predicted values had an error of less than one-half of the actual height gain.CONCLUSIONS: This predictive model formula for calculating the potential postoperative height gain after surgical treatment can be used preoperatively to inform idiopathic scoliosis patients of what outcomes they may expect from posterior spinal instrumentation and fusion (taking into account the model’s uncertainty)
The Complete Genome Sequence of Cupriavidus metallidurans Strain CH34, a Master Survivalist in Harsh and Anthropogenic Environments
Many bacteria in the environment have adapted to the presence of toxic heavy metals. Over the last 30 years, this heavy metal tolerance was the subject of extensive research. The bacterium Cupriavidus metallidurans strain CH34, originally isolated by us in 1976 from a metal processing factory, is considered a major model organism in this field because it withstands milli-molar range concentrations of over 20 different heavy metal ions. This tolerance is mostly achieved by rapid ion efflux but also by metal-complexation and -reduction. We present here the full genome sequence of strain CH34 and the manual annotation of all its genes. The genome of C. metallidurans CH34 is composed of two large circular chromosomes CHR1 and CHR2 of, respectively, 3,928,089 bp and 2,580,084 bp, and two megaplasmids pMOL28 and pMOL30 of, respectively, 171,459 bp and 233,720 bp in size. At least 25 loci for heavy-metal resistance (HMR) are distributed over the four replicons. Approximately 67% of the 6,717 coding sequences (CDSs) present in the CH34 genome could be assigned a putative function, and 9.1% (611 genes) appear to be unique to this strain. One out of five proteins is associated with either transport or transcription while the relay of environmental stimuli is governed by more than 600 signal transduction systems. The CH34 genome is most similar to the genomes of other Cupriavidus strains by correspondence between the respective CHR1 replicons but also displays similarity to the genomes of more distantly related species as a result of gene transfer and through the presence of large genomic islands. The presence of at least 57 IS elements and 19 transposons and the ability to take in and express foreign genes indicates a very dynamic and complex genome shaped by evolutionary forces. The genome data show that C. metallidurans CH34 is particularly well equipped to live in extreme conditions and anthropogenic environments that are rich in metals
Conserved and highly expressed tRNA derived fragments in zebrafish
Background: Small non-coding RNAs (sncRNAs) are a class of transcripts implicated in several eukaryotic regulatory
mechanisms, namely gene silencing and chromatin regulation. Despite significant progress in their identification by
next generation sequencing (NGS) we are still far from understanding their full diversity and functional repertoire.
Results: Here we report the identification of tRNA derived fragments (tRFs) by NGS of the sncRNA fraction of
zebrafish. The tRFs identified are 18–30 nt long, are derived from specific 5′ and 3′ processing of mature tRNAs and
are differentially expressed during development and in differentiated tissues, suggesting that they are likely produced by specific processing rather than random degradation of tRNAs. We further show that a highly expressed tRF
(5′tRF-ProCGG) is cleaved in vitro by Dicer and has silencing ability, indicating that it can enter the RNAi pathway. A
computational analysis of zebrafish tRFs shows that they are conserved among vertebrates and mining of publicly
available datasets reveals that some 5′tRFs are differentially expressed in disease conditions, namely during infection
and colorectal cancer.
Conclusions: tRFs constitute a class of conserved regulatory RNAs in vertebrates and may be involved in mechanisms of genome regulation and in some diseases.
Keywords: tRNA derived fragments, Zebrafish, Small non coding RNAs, tRNAspublishe
Occlusion of LTP-Like Plasticity in Human Primary Motor Cortex by Action Observation
Passive observation of motor actions induces cortical activity in the primary motor cortex (M1) of the onlooker, which could potentially contribute to motor learning. While recent studies report modulation of motor performance following action observation, the neurophysiological mechanism supporting these behavioral changes remains to be specifically defined. Here, we assessed whether the observation of a repetitive thumb movement – similarly to active motor practice – would inhibit subsequent long-term potentiation-like (LTP) plasticity induced by paired-associative stimulation (PAS). Before undergoing PAS, participants were asked to either 1) perform abductions of the right thumb as fast as possible; 2) passively observe someone else perform thumb abductions; or 3) passively observe a moving dot mimicking thumb movements. Motor evoked potentials (MEP) were used to assess cortical excitability before and after motor practice (or observation) and at two time points following PAS. Results show that, similarly to participants in the motor practice group, individuals observing repeated motor actions showed marked inhibition of PAS-induced LTP, while the “moving dot” group displayed the expected increase in MEP amplitude, despite differences in baseline excitability. Interestingly, LTP occlusion in the action-observation group was present even if no increase in cortical excitability or movement speed was observed following observation. These results suggest that mere observation of repeated hand actions is sufficient to induce LTP, despite the absence of motor learning
O Design Universal Para Apprendizagem e a Pedagogia das Estacoes: As Multiplas Temporalidades / Espacialidades do Aprender nas Escolas.
This article explores school inclusion processes, with a view to problematizing the learning hegemonies of time and space in educational institutions. It presents partial results of the research project; 'A Escola Para Todos' (The School for All) and responds to the question: How can Universal Design for Learning (UDL), which is somewhat similar to the 'pedagogy of the seasons,' qualify inclusive experiences in schools? By providing an integrative review of the salient features of UDL and pedagogy of the seasons, the paper questions the hegemony of time-space teaching and learning in schools by drawing on narrative theory. Methodologically, this part of the research provides an integrated reflection on critical conceptual attributes incorporating; UDL, the temporalities and spatialities of learning, and concepts of inclusive education. The results of this stage of the research show that it is necessary to overcome the hegemony of time and linear space in learning and teaching processes in order to arrive at school inclusion. Despite similarities between UDL and 'pedagogy of the seasons' tensions remain between these approaches. Not least as reflected in the overcoming of paradoxes such as the necessity to address universal requirements while also tending to particular learner requirements, or equally, while recognizing the variability of strategies without losing sight of more global pedagogical approaches. This challenge is accentuated when the UDL concept of 'expert learners' is further interrogated
Cultural transmission and biological markets
Active cultural transmission of fitness-enhancing behavior (sometimes called “teaching”) can be seen as a costly strategy: one for which its evolutionary stability poses a Darwinian puzzle. In this article, we offer a biological market model of cultural transmission that substitutes or complements existing kin selection-based proposals for the evolution of cultural capacities. We explicitly demonstrate how a biological market can account for the evolution of teaching when individual learners are the exclusive focus of social learning (such as in a fast-changing environment). We also show how this biological market can affect the dynamics of cumulative culture. The model works best when it is difficult to have access to the observation of the behavior without the help of the actor. However, in contrast to previous non-mathematical hypotheses for the evolution of teaching, we show how teaching evolves even when innovations are insufficiently opaque and therefore vulnerable to acquisition by emulators via inadvertent transmission. Furthermore, teaching in a biological market is an important precondition for enhancing individual learning abilitie
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