RESUMO
Huntington's disease (HD) is an autosomal dominant, incurable neurodegenerative disease caused by mutation in the huntingtin gene (HTT). HTT mutation leads to protein misfolding and aggregation, which affect cells' functions and structural features. Because these changes might modify the scattering strength of affected cells, we propose that random lasing (RL) is an appropriate technique for detecting cells that express mutated HTT. To explore this hypothesis, we used a cell model of HD based on the expression of two different forms-pathogenic and non-pathogenic-of HTT. The RL signals from both cell profiles were compared. A multivariate statistical analysis of the RL signals based on the principal component analysis (PCA) and linear discriminant analysis (LDA) techniques revealed substantial differences between cells that expressed the pathogenic and the non-pathogenic forms of HTT.
Assuntos
Doença de Huntington , Doenças Neurodegenerativas , Humanos , Proteína Huntingtina/genética , Doença de Huntington/genética , MutaçãoRESUMO
Academic performance during the first year of university is correlated with future academic success, and is considered to be a determining factor in the reduction of dropouts. In the present study, we describe a new academic performance indicator for the first term of first-year science degrees students at La Laguna University in Spain. We are interested in identifying the most important previous academic factors for predicting the success of first-year students at university. Specifically, multiple linear regression models were used to identify such predictors of academic success. We report that, for all of the analyzed science degrees, the best predictor of academic success is high school grade point average. In addition, we obtained predictive models for estimating the value of the new academic performance indicator. Using these models, we can predict future academic success, which may help identify students at risk of failure at the beginning of the course. This in turn would ensure early implementation of educational interventions or strategies to increase academic achievement of such students.
Assuntos
Desempenho Acadêmico , Sucesso Acadêmico , Avaliação Educacional , Ciência/educação , Universidades , Adolescente , Feminino , Humanos , Masculino , EstudantesRESUMO
BACKGROUND: The authors previously observed that some high-performance athletes, irrespective of type of sport, can show echocardiographically determined low left ventricular ejection fractions (LVEF; <52%) together with normal heart rates and nondilated left ventricular (LV) cavities under resting conditions. The aim of this study was to determine if this phenomenon is associated with dyssynchronous motion of the interventricular septum relative to the lateral LV wall. METHODS: Results of M-mode and two-dimensional echocardiography and pulsed-wave, pulsed-wave tissue, and color tissue Doppler were compared in 70 athletes (mean age, 20 ± 7 years; 77% men) with low LVEFs (<52%) participating in a wide variety of sports and a control group of 564 athletes (mean age, 22 ± 7 years; 61% men) with normal LVEFs (≥52%). RESULTS: No between-group differences were found in cardiac dimensions or QRS duration (indicating no electrical dyssynchrony in the low-LVEF group compared with the normal-LVEF group), but analysis of mechanical interventricular and intraventricular dyssynchrony showed that time intervals between QRS onset and the different systolic waves were all lengthened in the low-LVEF group (P < .05 for all). Values of interventricular mechanical delay were higher in the low-LVEF group (P = .012), though they did not reach pathologic limits. Peak aerobic performance was independent of LVEF. The results did not change materially when analyzing data separately by sex or sport. CONCLUSIONS: Some young highly trained athletes might show depressed LVEF (<52%) with a nondilated LV cavities in the early phase of cardiac adaptations, which seems to be linked to longer LV contraction times, with the right ventricle unaffected. These echocardiographic findings, although not highly prevalent, could be considered another characteristic of the cardiac adaptations to the demands of elite sports with no detriment in performance.