99 research outputs found
Detailed and GlobalAnalysis of a Remedial Course's Impact on Incoming Students' Marks
Engineering incoming students are facing great difficulties to overcome first course subjects. To tackle that situation and increase the studentsâ success a Remedial course in Mathematics was offered to Informatics Engineering freshmen. This study presents a statistical analysis of their results comparing the marks obtained by those joining the course (studio group) versus those who did not participate (control group). ANOVA tests are performed over the studentsâ marks averages as well as over each subject students marks. These tests show statistically significant differences between both groups, with the studio group consistently outperforming the control group at 99% confidence level in most cases and at more than 92% confidence level in every case
Melatonin MT1 and MT2 receptors in the ram reproductive tract
Some melatonin functions in mammals are exerted through MT1 and MT2 receptors. However, there are no reports of their presence in the reproductive tract of the ram, a seasonal species. Thus, we have investigated their existence in the ram testis, epididymis, accessory glands and ductus deferens. Real-time polymerase chain reaction (qPCR) revealed higher levels of m-RNA for both receptors in the testis, ampulla, seminal vesicles, and vas deferens, than in the other organs of the reproductive tract (p < 0.05). Western blot analyses showed protein bands compatible with the MT1 in the testis and cauda epididymis, and for the MT2 in the cauda epididymis and deferent duct. Immunohistochemistry analyses revealed the presence of MT1 receptors in spermatogonias, spermatocytes, and spermatids, and MT2 receptors in the newly-formed spermatozoa in the testis, whereas both receptors were located in the epithelial cells of the ampulla, seminal vesicles, and ductus deferens. Indirect immunofluorescence showed significant differences in the immunolocation of both receptors in spermatozoa during their transit in the epididymis. In conclusion, it was demonstrated that melatonin receptors are present in the ram reproductive tract. These results open the way for new studies on the molecular mechanism of melatonin and the biological significance of its receptors
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The evolution of the Behavioural Approach System (BAS): Cooperative and competitive resource acquisition strategies
The nature of approach motivation has not yet been adequately defined. Some authors view it as a unidimensional construct, while others consider it to be multidimensional. Its psychometric nature is explored in this study, which tests empirically the motivational account of the Behavioural Approach System (BAS) within an evolutionary context. In a sample of 394 participants, we administered the Assessment of Individual Motives questionnaire (AIM-Q), the Reinforcement Sensitivity Theory Personality Questionnaire (RST-PQ) and a short version of the Sensitivity to Punishment and Sensitivity to Reward (SPSRQ-20). The results of set correlation analysis indicated that different BAS scales relate to different motives, thus supporting the multidimensional perspective on approach motivation. Specifically, Reward Interest relates to various types of motives that generally reflect sensitivity to social rewards; Goal-Drive Persistence relates to social exchange, Reward Reactivity to safety and commitment; while Impulsivity and Sensitivity to Reward (SR) relate to competitive motives. These results are discussed within an evolutionary framework for the multidimensionality of the BAS
A community-powered search of machine learning strategy space to find NMR property prediction models
The rise of machine learning (ML) has created an explosion in the potential
strategies for using data to make scientific predictions. For physical
scientists wishing to apply ML strategies to a particular domain, it can be
difficult to assess in advance what strategy to adopt within a vast space of
possibilities. Here we outline the results of an online community-powered
effort to swarm search the space of ML strategies and develop algorithms for
predicting atomic-pairwise nuclear magnetic resonance (NMR) properties in
molecules. Using an open-source dataset, we worked with Kaggle to design and
host a 3-month competition which received 47,800 ML model predictions from
2,700 teams in 84 countries. Within 3 weeks, the Kaggle community produced
models with comparable accuracy to our best previously published "in-house"
efforts. A meta-ensemble model constructed as a linear combination of the top
predictions has a prediction accuracy which exceeds that of any individual
model, 7-19x better than our previous state-of-the-art. The results highlight
the potential of transformer architectures for predicting quantum mechanical
(QM) molecular properties
Reward and Punishment Sensitivity in Children with ADHD: Validating the Sensitivity to Punishment and Sensitivity to Reward Questionnaire for Children (SPSRQ-C)
This study validates the Sensitivity to Punishment and Sensitivity to Reward Questionnaire for children (SPSRQ-C), using a Dutch sample of 1234 children between 6â13Â years old. Factor analysis determined that a 4-factor and a 5-factor solution were best fitting, explaining 41% and 50% of the variance respectively. The 4-factor model was highly similar to the original SPSRQ factors found in adults (Punishment Sensitivity, Reward Responsivity, Impulsivity/Fun-Seeking, and Drive). The 5-factor model was similar to the 4-factor model, with the exception of a subdivision of the Punishment Sensitivity factor into a factor with âsocial-fearâ items and a factor with âanxietyâ items. To determine external validity, scores of three groups of children with attention deficit hyperactivity disorder (ADHD) were compared on the EFA models: ADHD-only (nâ=â34), ADHD and autism spectrum disorder (ADHD+ASD; nâ=â22), ADHD and oppositional defiant disorder (ADHD+ODD; nâ=â22). All ADHD groups scored higher than typical controls on Reward Responsivity and on the âanxietyâ factor (nâ=â75). The ADHD-only and ADHD+ODD group scored higher than other groups on Impulsivity/Fun-Seeking and Drive, while the ADHD+ASD group scored higher on Punishment Sensitivity. The findings emphasize the value of the SPSRQ-C to quickly and reliably assess a childâs sensitivity to reinforcement, with the aim to provide individually-tailored behavioral interventions that utilize reward and reprimands
Reward-Related Dorsal Striatal Activity Differences between Former and Current Cocaine Dependent Individuals during an Interactive Competitive Game
Cocaine addiction is characterized by impulsivity, impaired social relationships, and abnormal mesocorticolimbic reward processing, but their interrelationships relative to stages of cocaine addiction are unclear. We assessed blood-oxygenation-level dependent (BOLD) signal in ventral and dorsal striatum during functional magnetic resonance imaging (fMRI) in current (CCD; nâ=â30) and former (FCD; nâ=â28) cocaine dependent subjects as well as healthy control (HC; nâ=â31) subjects while playing an interactive competitive Domino game involving risk-taking and reward/punishment processing. Out-of-scanner impulsivity-related measures were also collected. Although both FCD and CCD subjects scored significantly higher on impulsivity-related measures than did HC subjects, only FCD subjects had differences in striatal activation, specifically showing hypoactivation during their response to gains versus losses in right dorsal caudate, a brain region linked to habituation, cocaine craving and addiction maintenance. Right caudate activity in FCD subjects also correlated negatively with impulsivity-related measures of self-reported compulsivity and sensitivity to reward. These findings suggest that remitted cocaine dependence is associated with striatal dysfunction during social reward processing in a manner linked to compulsivity and reward sensitivity measures. Future research should investigate the extent to which such differences might reflect underlying vulnerabilities linked to cocaine-using propensities (e.g., relapses)
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